摘要:

WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock. Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent. Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it.In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.

ISSN:0003-2654    

DOI:10.1039/AN9356000131

出版商:RSC    

年代:1935

数据来源: RSC

摘要:

WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock. Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent. Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it.In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.

ISSN:0003-2654    

DOI:10.1039/AN9356000132

出版商:RSC    

年代:1935

数据来源: RSC

摘要:

135 The Question of Tannin in Mate BY W. A. WOODARD AND A. N. COWLAND (WORK DONE UNDER THE SOCIETY’S ANALYTICAL INVESTIGATION SCHEME) (Read at the Meeting December 5 1934) 1 NTRODUCTI0N.-In South America and associated countries a beverage is made from mat6 the dried leaves of various species of Ilex (Fam. Apijoliaceae)-shrubs indigenous to Brazil and Argentina. It is usual to take the drink as an aqueous infusion prepared in a silver cup or gourd from which the name “ mat6 ” is derived. Owing to the discovery of the shrub in Paraguay by early Jesuit missionaries in the seventeenth century all varieties of mat& irrespective of species have come to be known as Ilex paraguayensis. The genus Ilex however contains two-htmdred-and-eighty species and Wehmerl gives the names of nine different varieties of Ilex leaves sold under the name of mat6.To-day the finest variety obtainable is derived from Ilex paraguariensis (St. Hilaire) and in Parana it is forbidden by law to export any other. The process for curing mat6 is distinct from that used for common “tea”; moreover it is unlikely to produce any appreciable change in the phenoli 136 WOODARD AND COWLAND THE QUESTION OF TANNIN IN MATE constituents of the plant. In several publications it is stated that mat6 is dried by means of smokeless heat.* According to the descriptions given in abstracts from this literature and elsewhere the modern curing process may be summarised roughly as follows:-The twigs and leaves are collected between May and September this period being fixed by law to avoid damage to the shrubs.First there is a preliminary toastifig and drying by means of hot air; direct heat is carefully avoided because smoke would give the finished product an undesirable taste and odour. Secondly after a definite period of storage the leaves and twigs are separated by means of a special threshing process. Lastly the leaves are subjected to a final drying by means of hot air conveyed through pipes or tunnels. The final product should be green, hard and resistant to fermentation and deterioration. The presence in mat6 of so-called tannin either identical with or analogous to that in tea has been definitely reported by several chemists but it should be pointed out that little or no work has been done on the phenolic constituents of the drug since 1922.This was before the advent of such specific tests as that requiring the use of goldbeaters’ skin and we have therefore made a critical examination of the results of earlier work. The more important references are as follows:-Rochleder and Hlasiwetz2 concluded that the main phenolic constituent of mat6 was identical with the caffetannin of coffee. Arata3 found the plant phenol to be analogous to but not identical with that of coffee. Peckolt4 published a con-firmation of Arata’s work. Kunz-Krauze5 described the main constituent as a glucoside of either caffeic or chlorogenic acid containing an unknown optically inactive hexose. Peacock and Peacock6 concluded on very slender evidence that mate contained an astringent principle which thev isolated and identified as a phlo baphene.At the suggestion of the Society’s Analytical Investigation Scheme Committee we have made a further investigation dealing primarily with the question of the presence of genuine tannin ; secondary considerations were the establishment of a difference between the plant phenols of mat6 and common “tea” and an attempt to separate colouring matter from the main plant phenol in mat@ with the object of obtaining data relating to their constitution and structure. PRELIMINARY EXAMINATION.-Thirty individual samples of cured m a t e ‘ wci-e examined including imports dating as far back as 1920 and 1927 as well as current imports from wholesale houses and purchases from London stores. A cursory botanical examination showed that all the samples were typical of the genus Ilex, although there was undoubtedly some variation in species.A small and limited supply of each kind of mat6 for comparison purposes was obtained by courtesy of the authorities at Kew. Coffee beans (Cofea arabica) and Asiatic tea leaves (Thea chinensis) were also compared with mat6 with a view to bringing out essential similarities and differences. Except in certain instances, aqueous extracts (1 in 20) were used for the tests. The extracts were prepared by decocting the comminuted material with water for fifteen minutes; when necessary, * “Mati: An Important Brazilian Product,” by C. R. Cameron (Bulletin ofthe Pan-American Union Oct. 1929 pp. 988-1005); “I1 M a t o Ti del Paraguay,” by Dr. C . Micastro (L’AgricoEtura Coloniale Nov.1928 t o Aug. 1929); A Exploracao do Mate” (Boletin do Ministerio da Agricultura Industria e Commercio Brazil for April and May 1929). Tea is rolled and fired mat6 is not WOODARD AND COWLAND THE QUESTION OF TANNIN IN MAT& 137 chlorophyll caffeine fats waxes resins etc. were removed by treatment with organic solvents. It will be realised by those familiar with the analysis of tannins that the available tests capable of giving specific results are very few. In this work, particular emphasis has been laid on the results obtained with goldbeaters’ skin,? gelatin solution and certain tests devised by Ware all of which with certain exceptions are described in Allen’s Commercial Organic Analysis Volume V under the section dealing with tanninsg It was found necessary to employ a limited number of colour reactions but only those were used with which it was considered possible t o carry out control tests.Aqueous extracts of mat6 had the following general characteristics:-Yellowish-brown in colour giving an acid reaction to litmus (pH 5 to 6 ) ; they gave precipitates with solutions of cinchonine and quinine sulphates and a copious yellow precipitate with basic lead acetate; ferric iron (with increasing PH) gave a grass-green colour whereas ferrous iron (with carefully controlled decreasing $H} gave green violet purple and deep brown colours ; aqueous ammonia (10 per cent .) gave a beautiful emerald-green which deepened rapidly on shaking or allowing the mixture to stand in contact with air. The reactions with iron salts were particularly interesting especially when considered in conjunction with the results of tests for genuine tannin detailed in the next section of this paper.The results given with ferrous iron (Mitchell’s ferrous tartrate reagent)s have special significance when interpreted according to Ware.10 Ware11 classified plant phenols by the colours and precipitates obtained with the ferrous tartrate reagent in the presence of an appropriate quantity of N/50 sodium bicarbonate solution or a weak solution of ammonia; if no colour is obtained the phenol is provisionally assigned to class A; a violet colour indicates probably a phenol of class B and a deep brown colour probably a phenol of class C. Mat6 extracts gave results typical of classes B and C ; the more important phenols belonging to class B are pyrocatechol protocatechuic acid the cate-chinols (catechins) chlorogenic acid caff et annin ipecacuanhic acid adrenalin and catechol tannins; class C (containing most of the pyrone and quinonoid phenols and some benzophenone phenols) is represented chiefly by the anthoxanins such as the flavone luteolin and the flavonols morin quercetin quercetrin rutin myricetin, etc.It is not practicable to set out here in full all the tests used to show the absence of various phenols from mat6; it is sufficient to state that the following substances were thoroughly tested for particular attention being paid to the possible presence, in the free state of the first two in the list :-Gallic acid catechol protocatechuic acid resorcinol and phloroglucinol.There was no evidence indicating the presence, in the free state of any of these substances. Another qualitative reaction of extracts of mat6 is the beautiful emerald-green colour obtained with ammonia. We believe this reaction to be characteristic of mat6 and probably of caffetannin; the colour is very intense persisting for several hours and slowly changing on long contact with air to a deep brown. This is undoubtedly an oxidation reaction because the colour can also be obtained with acid permanganate and conversely can be completely and rapidly destroye 138 WOODARD AND COWLAND THE QUESTION OF TANNIN IN MATI? by reduction with zinc and hydrochloric acid. Aqueous extracts of coffee beans gave a similar reaction but the colour was very much less intense.It is well known that under suitable conditions many phenols (notably gallic acid gallotannin catechol protocatechuic acid and resorcinol) will give a green colour with ammonia or other alkali but the colour is usually very transient and much less intense than that given by mat6 extractives; moreover it must be recalled that four of the above-mentioned substances have been shown by many tests to be absent from mate. There has been a general tendency in the past to associate chlorogenic acid with this peculiar green colour given by various extracts with ammonia solution; furthermore it has been customary to identify caffetannin with chlorogenic acid in spite of the fact that the evidence for their identity is very slender. Nierenstein,12 dealing with hydrolysable tannins gives good reasons for the conclusion that caffetannin and chlorogenic acid are not identical.Gorter,13 describing the reactions of chlorogenic acid isolated from coffee makes it clear that it gives with ammonia not a green colour but a definite yellow which on standing acquires a reddish tint. The preliminary examination of mat6 extracts indicated the presence of two plant phenols viz. an iron-greening anthoxanin (probably a flavone or flavonol derivative) which was responsible for the deep brown colour given with Mitchell’s reagent in the presence of sufficient alkali; and secondly what is here described as a pseudo-tannin (probably a caffetannin) which gave the violet colour with Mitchell’s reagent also in the presence of sufficient alkali ; appreciable quantities of these two phenols undoubtedly exist in mat& As will be seen the results recorded at a later stage of this work tend t o substantiate this suggestion.EXAMINATION OF FRESH AND CURED MATB FOR TANNIN.-The more important results are given below in tabular form the tests used being all fairly well known, with perhaps the exception of the antipyrine test devised by Ware24 This routine test for tannins used in conjunction with a suitable phosphate buffer gave excellent results with controls containing very small amounts of gallotannin. TABLE I Test Goldbeaters’ skin (a) Treatment for tanning (b) Staining with ferrous sul-(c) Decolorisation with acid Gelatin solution phate Ware’s antipyrine test Ware’s iron and ammonium Ware’s modification of citrate test Stiasny ’s reaction Ware’s modification of Mitchell’s ferrous tartrate test Observation No opacity Greyish-green stain No final stain Complete absence of turbidity No turbidity or precipitate No precipitate or precipitate No characteristic Precipitate Iron-greening and iron-No blue colour produced No blue or violet colour pro-browning filtrate duced Inference Tannin absent Indication of iron-greenicg snthoxanin Phlobaphen absent Tannin absent Tannin absent Tannin absent Phlobatannin absent Gallotannins absent Gallotannin absen WOODARD AND COWLAND THE QUESTION OF TANNIN IK MATE 139 In addition to the tests described above a hide-powder test kindly made by Dr.E. W. Merry of The British Leather Manufacturers' Research Association, gave noteworthy results.The comminuted material (25 g.) was extracted with 11. of water in a Procter extractor at a temperature not exceeding 60" C. The sample contained 33.2 per cent. of water-soluble substances of which 12 per cent. was absorbed by the hide powder as used in the official method of tanning analysis; the remaining 21.2 per cent. was not absorbed. Lack of sufficient fresh material made it impossible to make a control test; but since hide powder will absorb substances other than tannins including natural colouring matters and non-volatile organic acids we suggest that the absorption in the case of mat6 was due to the presence of one or both of these constituents in the leaves of the plant. The results of sensitive spot-tests on filter-paper devised by Ware,15 confirmed the foregoing conclusions ; the same author's tests with iodine and ammonia were also confirmatory.It is noteworthy that the goldbeaters' skin test the most specific test known for detecting genuine tannin gave a negative result with each of the thirty samples of mat6 examined. We conclude that there is not and never has been any genuine tannin in mate for the following reasons: (a) First and foremost there is no phlobaphen present. ( b ) There is no gallic acid present. (c) The modern process by which the leaf is cured is unlikely to produce tannin or to destroy it. A COMPARISON OF FRESH MAT^ WITH FRESH TEA.-These tests bring out certain pronounced differences between mat6 and tea. Little can be said about the plant phenols in tea because the chemistry of tea-tannin is a mass of con-tradictions and requires further elucidation.Comparisons were also made with fermented tea but the results were so similar to those given in Table I1 that there was no point in recording them. The only noticeable difference between fresh and ferrnented tea was that the cured material gave strong positive results for phlobaphen whereas the fresh tea did not. I t is clear from these results that so far as qualitative tests go there is little similarity between mat6 and tea. Tea undoubtedly contains genuine tannin but mat6 does not and this constitutes the chief and most far-reaching difference between the two. A COMPARISON OF FRESH MATB WITH FRESH COFFEE.-These tests bring out differences and similarities between mat6 and coffee.A comparison of the cured materials also gave very similar results except that with coffee the reactions were much less intense; this was probably due to destruction of plant phenols during roasting. Coffee beans are known to contain caffetannin and chlorogenic caffeic and gallic acids. From the comparison given on p. 140 it seems probable that a little genuine tannin is also present; this would be quite feasible since it is rare t o find gallic acid unassociated with tannin in a plant. It is noteworthy that the re-markable reaction with ammonia (p. 137) is also shared by extracts of coffee 140 WOODARD AND COWLAND THE QUESTION OF TANNIN IN MAT& Test Goldbeatcrs’ skin Gelatin solution Ware’s modification of Stiasny’s reaction Osmium tetroxide soh-tion (1 per cent.) + ap-propriate buffer Bromine water Nierenstein’s test (0.5 per cent.diazobenzene chloride) TABLE I1 Observation Mat6 Already described. Tea Definite opacity with bluish-green stain Mat6 Already described Tea Characteristic precipitate Mati Already described Tea Characteristic precipitate, iron-blueing and iron-greening filtrate Mat6 Reddish-brown no violet Tea Purplish-violet or blue Mati: No precipitate on stand-Tea Precipitate on standing Mat& No precipitate on stand-Tea Precipitate on standing ing ing Inference Tannin present ; gallotannin, gallic acid or catechol tan-nin present -Confirmation of presence of tannin -Phlobatannin present gallo-tannin gallic acid or cate-chol tannin present acid gallol tannin Confirmed absence of gallic Probable presence of a pyro-Absence of catechol tannin Probable presence of catechol Absence of catechins or cate-Presence of onc or both of tannin chol tannin these substances SEPARATION OF THE PLANT PHENOLS IN MATfi.-The preliminary examination of mat6 extracts indicated the presence of two plant phenols one classified as a pseudotannin and the other as a member of the large family of natural yellow colouring matters.Perkin16 has called attention to the fact that many natural colouring matters and tannins associated in plants often show a marked resemblance t o each other in constitution and chemical reactions. Test Goldbeaters’ skin Solution of gelatin Ware’s modification of Stiasny ’s reaction Ammonia solution 10 per cent.Osmium tetroxide soh-tion (1 per cent.) + ap-propriate buffer Nierenstein’s test (0.5 per cent. diazobenzene chloride) TABLE I11 Observation Mat6 Already described Coffee Slight opacity bluish-green stain Mat6 Already described Coffee Slight turbidity Mat6 Already described Coffee Very slight precipitate, iron-greening and iron-blueing filtrate Matk Beautiful emerald-green intensified on shaking Coffee Very similar to mat6 only less intense Mat6 Already described Coffee Same as matk but tinged with violet Mat6 Already described Coffee No precipitate on stand-ing This seemed probable with Inference Indication of‘ a little tannin; gallotannin gallic acid or a catechol tannin present --Confirmation of above result -Confirmation of above results Caffetannin present Caffetannin present -Probably a little gallic acid or tannin present -Absence of catechins and catechol tanni WOODARD AND COWLAND THE QUESTION OF TANNIN IN MATE 141 rnatk since the reactions of one phenol nearly always tended to be masked by those of the other.For this reason attempts were made to separate the two constituents. Fractional precipitation with lead gave poor results ; various attempts to remove the colouring matter by adsorption or oxidation were equally unsuccessful. Extraction with different organic solvents yielded towards the end of the work, some measure of success.It was noticed that neutral acetone extracted some colouring matter from mat6 but very little or no pseudotannin; alkaline acetone extracted a fair amount of colouring matter but again little or no pseudotannin; acidified acetone extracted both plant phenols in sufficient amount to afford hope of a good separation when the extract was treated with dry ammonia gas for a definite period. One kg. of dried and powdered mat6 was allowed to stand in contact with dry chloroform for six hours with occasional shaking. The chloroform was then decanted and the leaves were pressed; washing with several portions of ether and a final pressing of the leaves completed the removal of caffeine chlorophyll, fats resins waxes etc. I t goes without saying that the plant phenols in mat6 had previously been found to be almost insoluble in chloroform and ether.Next the pressed material was spread out on a tray and dried at a temperature not exceeding 60" C. Treatment with acidified acetone followed (@H 3 to 4, adjusted by means of concentrated sulphuric acid) sufficient solvent being added to cover the leaves completely and twenty-four hours being allowed for the extraction. The solution was filtered through a Buchner funnel and a fairly rapid current of dry ammonia gas was passed through the filtrate for about two minutes. The pinkish-red precipitate obtained was quickly washed with neutral acetone (several times) and then transferred to a desiccator to dry. The filtrate, containing colouring matter was again treated with ammonia gas any precipitate obtained being neglected; after re-filtering if necessary the new filtrate was evaporated to dryness under reduced pressure and the residue was transferred to a desiccator.This represents a rough attempt to separate the colouring matter from the plant phenol or pseudotannin but the method will probably need some re-adjustment before being applicable on a large scale. EXAMINATION OF THE PRECIPITATE.-The precipitate obtained by the method described had the following general characteristics :-It was readily soluble in water forming a clear reddish-brown solution; the reaction to litmus was markedly acid and the colour given with ammonia was the deep emerald-green already described ; ferric iron (with increasing @H) gave a grass-green colour whereas ferrous iron (with decreasing @H) gave green violet-purple and finally a deep wine-red colour but no brown colour was noticed.According to Ware,ll this reaction is typical of pseudotannins in general. Precipitates were obtained with cinchonine and quinine sulphates heating by itself yielded catechol and fusion with alkali gave catechol together with a volatile acid not yet identified. It is worth noting that the preliminary reactions for colouring matter and also others described later in detail gave negative results when applied to an aqueous solution of the above precipitate. The process actually used was briefly as follows 142 WOODARD AND COWLAND THE QUESTION OF TANNIN IN MATB Caffetannins give on hydrolysis (i) caffeic and (ii) quinic acid and a residue not yet fully investigated.Ho\/cooH v CH=CH.COOH (i) Caffeic acid Ho/\H (ii) Quinic acid Nierenstein (Zoc. cit.) is in favour of regarding caffetannin as a condensation product of (iii) chlorogenic acid the established formula of which is given below. HovCooH C OH CH=CH-CO-0-C V Hw'\H (E) Chlorogenic acid If this view be accepted the residue obtained on hydrolysis would be either (iv) tetrahydroxy-truxillic acid or (v) tetrahydroxy-truxinic acid. HOOC-CH-CH i l < 5 H €iO&r-(jH.COOH H4H-COOH €30- H-CH.COOH HO (v) Tetrahydroxy-truxinic acid HoQ-(iv) Tetrahydroxy-truxillic acid At present little is known of either of these acids ; moreover Nierenstein12 points out that in accepting the suggested formula for caffetannin it must be realised that the production of caffeic acid would be entirely due to the presence of some unchanged chlorogenic acid in the caffetannin.Finally he agrees with Gorter,ls who is of the opinion that caffetannin is a mixture of several substances including chlorogenic acid. An attempt was made to produce caffeic acid from the precipitate obtained from acidified acetone. The precipitate was treated with a slight excess of 10 per cent. aqueous potassium hydroxide solution and hydrolysed under reduced pressure for thirty minutes; after cooling the brown solution was acidified with dilute sulphuric acid and then shaken out with several portions of ether. The ethereal layers were mixed the solvent evaporated and the residue was taken up in a little water. This aqueous solution gave positive results in the following tests devised by Gorterf3 for caffeic acid obtained by him from coffee beans a grass-green colour with weak ferric iron solution; a lemon-yellow colour wit WOODARD AND COWLAND THE QUESTION OF TANNIN I N MATB 143 lead acetate solution and baryta water; ready reduction of silver nitrate and a yellow colour with ammonia solution changing to a reddish tint on standing.This last reaction is also shown by chlorogenic acid. The same tests were applied to a residue obtained by a method proposed by GriebeP' for determining chlorogenic acid in coffee. The method depends on the conversion of chlorogenic acid into caffeic acid by alkaline hydrolysis; the results were positive for caffeic acid. An attempt to produce quinic acid from the precipitate under discussion was based on the knowledge that this substance when distilled with sulphuric acid and manganese dioxide yields quinone.The precipitate was hydrolysed with excess of 30 per cent. aqueous potassium hydroxide solution for one hour; subsequent distillation with concentrated sulphuric acid and manganese dioxide, gave on standing a yellow deposit which was collected and identified as quinone. We fully realise that the results just described need further confirmation; nevertheless we maintain that there is at this stage of the work evidence for concluding that caffetannin or some closely allied substance is present in mate. As previously mentioned the search for a practical method of separating the two phenols in mat6 has only recently been successful and work is still in progress with the object of obtaining the pseudotannin and colouring matter in the crystalline state.Attempts were made to crystallise the pinkish-red precipitate described above but the final product was invariably a hard brittle mass. This may have been due to impurity or on the other hand possibly the precipitate is a mixture of substances; if so this would be another point in favour of caffetannin being present. Another possibility is that chlorogenic acid exists in the free state in mat& The tests described by Charauxls and by Gorter,lg depending on colour reactions with iron salts after acid hydrolysis of fresh extracts gave results indicating the presence of chlorogenic acid. Hoepfner20 describes a colorimetric method for determining chlorogenic acid in coffee; this was tested with mat6 coffee being used as a control and the result was positive.In spite of this we think that it is difficult to state definitely whether the reactions just described would be given by chlorogenic acid existing in the free state in mat6 or by the same acid existing as a component of a mixture such as caffetannin may be. This must be left for further investigation. EXAMINATION OF THE FILTRATE.-The presence of an iron-greening anthoxanin, probably a (vi) flavone or (vii) flavonol derivative was indicated by the results obtained in certain tests in the preliminary examination. 0 (vi) Flavone (vii) Flavonol Attention has been called to the fact that the reactions of one phenol inter-fered with those of the other; owing to this confusion it was thought at one tim 144 WOODARD AND COWLAND THE QUESTION OF TANNIN IN MATk that the colouring matter in mat6 was almost certainly a flavonol derivative but the separation process has made it possible to correct this error.The filtrate from the acid acetone precipitate should contain the colouring matter; a residue obtained from such a filtrate in the manner already described, gave the following general reactions It dissolved in water to give a pale yellow solution being slightly acid to litmus and giving a copious yellow precipitate with lead acetate; with ferric iron (increasing pH) a green colour was obtained; with ferrous iron (decreasing pH) there was a green colour which on adding suffi-cient N / 5 0 sodium bicarbonate solution became deep brown; no violet or purple colour was seen thus indicating according to Ware,ll that phenols belonging to class B had been eliminated; in other words plant colouring matter had been separated from pseudotannin.When heated alone the dry residue gave catechol; when fused with alkali it gave protocatechuic acid and phloroglucinol. The following results presented in tabular form sum up the more important reactions of the colouring matter in mat& TABLE IV Test Calico or wool mordanted with aluminium Ware’s iron and ammonium citrate test Willstatter’s reduction re-action Perkin’s test (air-oxidation of an alkaline solution fol-lowed by acid precipitation) Observation Bright yellow-no reddish tint -fairly fast to light; fluor-esced in ultra-violet light Production of a heavy brown precipitate Complete absence of any colour Definite precipitation after acidification Inference Flavone or flavonol present ; probably a flavone Presence of a catechol phloro-glucinol flavone or Aa-vonol Flavonols absent; flavone de-rivative probably present Flavone derivative present All natural.hydroxyflavones dye fabrics mordanted with aluminium a yellow shade the intensity of which is dependent upon the position of their hydroxyl groups. The yellow given by flavonols to mordanted calico is usually slightly tinged with red which serves as a useful distinction from flavones. Willstatter’s reduction test with zinc and hydrochloric acid is another useful reaction for distinguishing flavones from flavonols.A third reaction based on Perkin’s ob-servation that hydroxyflavones are not as a rule readily oxidised in alkaline solution serves as a useful confirmatory test. The tests for colouring matter in mat6 were controlled with oak-bark containing quercetin and onion-skin containing apigenin. We thus consider that there is good evidence pointing to the existence in mat6 of a flavone derivative. In further work it is hoped to obtain confirmation of this by preparing the colouring matter in the crystalline state and investigating its chemical constitution. CoNcLusroNs.-It has been shown that mat6 is completely free from genuine tannin. This is a matter of considerable importance in view of the effects of ordinary tea upon the digestion.It has also been shown that mat6 contains an appreciable amount of a natura WOODARD AND COWLAND THE QUESTION OF TANNIN IN MATB 145 yellow plant colouring matter; it is reasonably certain that this colouring matter is a derivative of flavone. Certain evidence has been obtained pointing to the presence in mat6 of caffetannin or some closely allied compound. Comparisons have been made with coffee and tea and attention has been drawn t o important differences and similarities. We wish to express our thanks to Dr. C. A. Mitchell and Dr. H. E. Cox for their help and for many useful suggestions received during the course of the work. Thanks are also due to Dr. M. Nierenstein and Mr. Alan Ware for confirming certain results and to Prof. 0.L. V. de Wesselow Director of the Medical Unit Laboratory, St. Thomas’s Hospital for kindly providing facilities for the work to be done. REFERENCES 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 16. 16. 17. 18. 19. 20. C. Wehmer Die Pflanzenstoffe,” 1911 p. 457. Jena. F. Rochleder and H. Hlasivetz Ann. Chem. Pharm. 1848 66 39; 1850 76 339; 1867, P. N. Arata Gazz. Chim. Ital. 1877 7 520. T. Peckolt Pharm. J. 1884 14 121. H. Kunz-Krauze Arch. Pharm. 1893 231 613. J. C. and B. L. de G. Peacock J. Amer. Pharm. Assoc. 1922 11 609. P. Price ANALYST 1924 49 25. Allen’s Commercial OrgaMic Analysis 6th Ed. Vol. V pp. 1-204. C. A. Mitchell ANALYST 1923 48 2. A. Ware Quart. J. Pharm. 1928 3 365. Ibid. 1926 1 377; ANALYST 1929 54 58.M. Nierenstein “The Natural Organic Tannins,” 1934 Chapter Vl p. 207. K. Gorter Annabn 1908 358 327; 1908 359 217. A. Ware Quart. J. Pharm. 1933 3 460; Pharm. J . 1933 131 148; ANALYST 1933, A. Ware Quart. J. Pharm. 1930 3 460. A. G. Perkin and A. E . Everest I ‘ Organic Colouring Matters,” 1918 p. 17. C. Griebel Chem.-Ztg. 1933 57 353; ANALYST 1933 58 621. C. Charaux J. Pharm. Chim. 1910 102 292. K. Gorter Rec. Trau. Chim. Pays-Bas 1912 31 281. W. Hoepfner Chem.-Ztg. 1932 56 991; -~NALYST 1933,58 100. 142 219. 58 703. THE MEDICAL UNIT LABORATORY ST. THOMAS’S HOSPITAL LONDON S.E.l DISCUSSIOK Dr. H. E. Cox congratulated the authors on adding so valuable a chapter to the study of mat& He drew attention to Capt. T. A. Joyce’s lecture on mat4 (Nature 1934 134 724) from which it appeared among much interesting matter, that the first chapter had been written in 1617 by Cornejo and now Mr.Woodard and his colleague had added one more. I t was particularly important to note that the authors had established the absence of true tannin as in commercial circles it was still asserted that about 7 per cent. of tannin was present. He thought it was a matter for congratulation that the authors had established the nature of the chlorogenic acid and the absence of tannins by definite chemical study and had not depended solely on colour reactions which were known to be somewhat erratic. It was significant that the hydrolysis yielded caffeic acid which was known to be a product of caffetannin and he hoped that they would succeed in establishing the identity of the hydrolysis products of the chlorogenic acid and also that they would continue their good work so that we might get to know something of the real constitution of the substances present 146 WOODARD AND COWLAND THE QUESTION OF TANNIN IN MATB Mr.WOODARD replied that they had been able to produce quinic acid on distillation with sulphuric acid. They had also been able to show that caffeic acid was present. Dr. C. A. MITCHELL said that the authors had made a valuable addition to the long series of papers that had been brought before the Society by way of the Analytical Investigation Scheme. When considering the conflicting statements upon the presence or absence of tannin in products such as mat6 it was necessary to have a clear conception of what was meant by “tannin.” Definitions for tannin were notoriously vague but it seemed reasonable to regard a tannin as a substance that would “tan,” and for this reason great importance attached to the results of the goldbeaters’ skin test which was essentially a “ tanning ’’ reaction.If this test gave negative results as it did with math there could be no true tannin present but it would be interesting to learn whether the authors had ascertained the nature of the substances that were adsorbed from the extract of mat6 by hide-powder. In view of the results obtained with goldbeaters’ skin they were evidently not tannins. Mr. R. L. COLLETT asked whether the green colour obtained with ammonia was also obtained with other alkalis. Mr.WOODARD replying said that he very much appreciated the remarks made by Dr. Cox. In the first place he would like to emphasise the fact that the work dealt primarily with the question of genuine tannin in mate and that most of the time at their disposal had been devoted to this purpose. Also he was of opinion that before any useful knowledge bearing on the chemistry of the plant phenols in mat6 could be gained it would be necessary first to separate colouring matter from essential plant phenols and then to purify the products so obtained. This was not an easy matter although he was pleased to say that reasonable success had been attained in making a separation of the two phenols and some evidence was given in support of their chemical identity. The green colour given by mat6 extracts with ammonia was also obtained with solutions of sodium and potassium hydroxide although the colour was much less intense. He had observed that the green colour was destroyed by acids alone as well as by reduction with zinc and hydrochloric acid. With regard to the points raised by Dr. Mitchell, he had not considered it necessary to make a full investigation of the substances adsorbed by hide-powder. Since all tests for genuine tannin gave negative results with mat6 and also since hide-powder was known to adsorb both colouring matter and non-volatile organic acids he considered the adsorption in this case to be due to the presence of one or both of these constituents in the leaves. The green colour given by alkalis with aqueous mat& extracts was similar in many respects to the bluish-green colour given by coffee extracts under identical conditions. This reaction was commonly attributed to viridic acid but he thought that this conclusion was a little too hasty. Viridic acid was a substance of unknown constitution since according to Vlaaderen and Nhulder ( J . prakt. Chem. 1858, 67 261) there were at least six different kinds of viridic acid in coffee beans. His own observations led him to regard this interesting colour reaction as an indication of the presence of caffetannin or some closely allied compound

ISSN:0003-2654    

DOI:10.1039/AN9356000135

出版商:RSC    

年代:1935

数据来源: RSC

摘要:

STUBBS THE HORTVET FREEZING-POINT PROCESS 147 The Hortvet Freezing-point Process for the Examination of Milk Correction Factors and the Influence of Stirring I BY J. R. STVBBS M.Sc. F.I.C. (Read at the Meeting of the North of England Section December 8 1934) INTRODUCTION HORTVET with his collaborators under the scheme adopted by the American Association of Agricultural Chemists began work in the year 1917 on the problem of evolving an apparatus and a technique for the determination of the freezing-point of milk. He aimed at producing a cryoscope which would be convenient to use and by which results could be rapidly obtained with sufficient accuracy for the purpose of examining milk. Other workers notably Raoult and Monier-Williams, had described forms of apparatus by which accurate results could be obtained, but their cryoscopes were elaborate and difficult to manipulate and a considerable expenditure of time was necessary to carry out an observation thus rendering them quite unsuitable for routine work.The position cannot be better described than in the words of Monier-Williams1 :-“ The use of such comparatively complicated apparatus as that shown on page 8 is quite out of the question except for purposes of research ” ; and again “ The apparatus that I used was too elaborate for routine work. ’2 Hortvet on the other hand remarks “There does not appear to be any fairly defined uniformity in respect to design and construction of apparatus. . . . In order to satisfy practical requirements an attempt has been made to unify the conditions which have been outlined by giving attention chiefly first to the construction of a suitable cryoscope and thermometer; and second to the method of manipulation.The cryoscope . . . has been designed to serve the purposes under discussion; . . . the application of correction factors may for all practical purposes be avoided by means of a carefully standardised method of pr~cedure.”~ This standardised form of instrument and technique was completed in the year 1921 accepted by the A.O.A.C. and became an official m e t h ~ d . ~ It has since been fairly extensively used in this country and in the year 1933 the Council of the Society of Public Analysts recommended that it should be adopted for the examination of milk? It is interesting to observe in passing that both Raoult and Monier-Williams felt the need for a less elaborate form of apparatus which would serve for ordinary purposes and each produced a simplified design of cryoscope.Experience seems to show that by the use of the Hortvet apparatus reliable and concordant results can be obtained with a minimum expenditure of time and trouble and provided that the technique laid down by the regulations is followed, the results of one observer are comparable with those obtained by others. After a somewhat extensive use of the cryoscope for several years I have no hesitation in saying that the process is as rapid as any other suggested process; indeed, it is probably the speediest of all; it is economical requiring very little ether; it is much more convenient and agreeable to work than processes in which mixtures o 148 STUBBS THE HORTVET FREEZING-POINT PROCESS FOR THE EXAMINATION ice and salt are employed as the cooling agent; it is under strict control and it is possible and usual to obtain concordant results in duplicate experiments both by the same observer and also by different observers; and finally the degree of accuracy is more than sufficient for the practical purposes for which the examina-tion of milk is undertaken.But the process has been criticised in some quarters particularly by Monier-Williams who has raised objections both to the type of stirrer and to the method of stirring. Thus there are raised the questions whether the results obtained by the use of the Hortvet process will be affected materially by varying rates of manipula-tion of the Hortvet stirrer and whether the use of a more efficient stirrer will cause differences in the results; if so what will be the extent of the variations? The work described in the first part of this paper was undertaken with the object of answering these questions.I t has also been stated both in the literature and during discussions I have had with other workers that the Hortvet apparatus and technique do not give a figure from which there can be readily ascertained the “true” freezing-point of milk i.e. the temperature at which milk and ice are in equilibrium with each other, so that the quantity of ice remains constant in amount; that it is difficult if not impossible with the standard Hortvet apparatus to arrive a t the corrections which should be applied to the observed or apparent freezing-point on account of super-cooling and of heat transference while the temperature is rising after crystallisation begins.The apparatus used in all this york was the modified Hortvet cryoscope, referred to in a previous paper,s and explained in the second part of the present paper. For the experiments recorded in the first part of the paper to ascertain the influence of stirring the alcohol was retained as is the case in the usual method of working with the standard Hortvet cryoscope. Unless otherwise stated, stirring was in all cases effected by means of an electric motor causing the stirrer to work at the rate of 40 complete strokes (each stroke consisting of an up-and-down movement) in a minute.The thermometer used throughout the first series of experiments recorded in the first and second parts of the paper was an American one which still continues to be very satisfactory after being in use for about three years. I t is the one whose good performance is referred to in the paper mentioned above and as there stated its indications of the freezing-point of water appear to be nearly independent of any influence excepting variations in the barometric pressure. The readings were taken with a small hand-lens by which the graduations are in focus when the distance between the lens and the thermometer is about 44mm. from the thermometer. The bulk of the work was repeated after a lapse of about three months when the readings of the thermometer were observed by means of the telescope of a cathetometer.The instrument was clamped to a heavy table which in turn was screwed to the floor. Two spirit levels were attached to the frame and one to the telescope for the purpose of adjustment. The distance between the end of the telescope and the thermometer was twenty-two inches. The thermometer was adjusted to the vertical position by two plumb lines attached to a movable arm These points are dealt with in the second part of this paper O F MILK CORRECTION FACTORS AND T H E INFLUENCE OF STIRRING I 149 by means of which they could be removed when not required. After a reading had been taken the position of the thermometer was checked to ascertain if tapping had displaced it from the vertical position. The time required to make a reading with this levelled telescope is very little, if any longer than that needed when a hand-lens is used.While the cooling of the milk is taking place the instrument and telescope are levelled and the cross-wires of the telescope brought to bear on the thermometer at about the expected position of the mercury at the freezing-point. Three readings were usually taken with both the telescope and the hand-lens, and it was found that there was no appreciable difference between readings of the same position of the mercury by the two methods. Experience showed that, after adequate practice the hand lens gave readings sufficiently accurate for all practical purposes. Another thermometer also of American manufacture which has proved very satisfactory for some months was used for the purpose of repeating the work.The zero-point of the thermometer was checked frequently at least once each working day. The samples of milk used in all the following work were of good quality as judged by the chemical analysis and their smell and acidity indicated that they were quite fresh. The temperature of the cooling-bath was maintained at -3.0" C. throughout all the experiments on milk except in one instance mentioned later; in the case of water a temperature of - 2.5" C. was used. PART I INVESTIGATION OF THE EFFECT OF DIFFERENT METHODS OF STIRRING Comparison of the use of the Hortvet stirrer with that of aJlat and more eficient The Hortvet stirrer is described in the Methods of Analysis of the A.O.A.C. (3rd Edition p.220) as composed of non-corrodible low-conductivity metal . . . the lower end provided with a horizontal loop. It is essentially a length of wire having a loop at right angles at one end whilst the other end is provided with a handle of insulating material. This stirrer is to be used with a steady up-and-down motion at the rate of approximately one stroke in one or two seconds. When the desired amount of super-cooling has been obtained freezing is induced and the thermometer indicates a rise of temperature. The instructions are that when the freezing-point of water is being ascertained the stirrer should be manipulated slowly and carefully three or four times as the mercury approaches its highest point. In the case of milk the stirrer is to be similarly used two or three times at the corresponding point.In effect then when the instructions are followed the stirrer is at rest from the moment when freezing begins until the column of mercury " approaches " its highest point. I t will be obvious that within reasonable limits it can be of little consequence what rate of stirring is adopted while cooling is taking place provided that it is effective in mixing the liquid in the freezing-tube so that the temperature indicated (1) one 150 STUBBS THE HORTVET FREEZING-POINT PROCESS FOR THE EXAMINATION by the thermometer is the same as that of the different parts of the liquid; it might be expected that an increase in the rate of stirring would have the effect of reducing the time needed for cooling in spite of the slight amount of extra heat generated by the more vigorous agitation and that a reduction in that rate would produce the opposite effect.It would appear that in the Hortvet process the question of stirring while the temperature is rising after freezing has begun might assume greater significance, for the final temperature attained is the resultant of at least two opposing effects, viz. the abstraction of heat from the freezing liquid by the cooling-bath and the addition of heat due to the latent heat of formation of ice. Vigorous stirring might be expected by exposing fresh layers of the liquid under examination to the walls of the freezing-vessel themselves cooled by the cooling-bath to promote extraction of heat while at the same time increasing the rate at which the liquid is heated up by bringing the particles of ice more quickly into contact with the different parts of the liquid.It must be admitted that the procedure as regards the use of the stirrer in the Hortvet technique during the period now under consideration stands alone and in distinct contrast with that adopted by most prominent observers. Raoult, when examining dilute solutions used a large platinum stirrer fitted with two helical vanes which was fixed over the bulb of the thermometer and both stirrer and thermometer were rotated together at the rate of 300 revolutions per minute. Monier-Williams in the experiments recorded in his work published in the year 1914 employed a glass spiral stirrer rotating at a speed of 1300 revolutions per minute while in his later experiments in 1933 he used an up-and-down flat or disc stirrer manipulated at the rate of one up-and-down stroke every two or three seconds.From a consideration of the above it will be quite clear that no claim can be put forward that in the Hortvet process the mixing together of the ice and the liquid will bear comparison as regards thoroughness and speed with that adopted in the technique of Raoult and of Monier-Williams. This point indeed would appear so obvious that it can hardly have escaped the notice of Hortvet and his collaborators; it seems reasonable on the other hand to presume that vigorous stirring was intentionally avoided. Monier-Williams definitely suggests that the stirring in the Hortvet method of procedure is “weak,” and in his later design of apparatus he himself uses as mentioned above a flat stirrer which may be described as a disc with a central hole for the thermometer and two smaller holes in place of the ring of wire used by Hortvet.Moreover Monier-Williams directs that this more efficient stirrer should be operated at the rate of one stroke (1 up-and-down motion) in two or three seconds all the time the temperature is rising until the tapping of the thermometer is carried out. So that Monier-Williams not only uses a more efficient stirrer but also uses it continuously. For the following experiments there was employed a stirrer made of thin sheet brass fastened to one end of the stem of a Hortvet stirrer in place of the ring of wire. The metal disc was 0-7 mm. in thickness and 29-5 mm. in diameter with a central hole 12.5 mm.in diameter and two small holes each 4 mm. in diameter OF MILK CORRECTION FACTORS AND THE INFLUENCE OF STIRRING I 151 opposite to each other. When this was substituted for the ordinary Hortvet stirrer it was quite obvious in manipulating it that a much more vigorous and thorough stirring was obtained; this was proved by the effort needed to work it, and also by the appearance of the milk which was agitated to such an extent that it was inclined to froth. In the experiments the results of which are given in Table I a comparison was made between the effect of the use of the Hortvet stirrer and the disc stirrer described above. The same portion of milk was used for an experiment with both types of stirrer; in the first experiment the Hortvet stirrer was used first followed by the flat one; in the second this order of use was reversed and so on alternately.Supercooling was carried out to approximately the same extent in every case, and never differed by more than 0.02" for the experiments on the same milk. In those cases where the Hortvet technique was used no stirring at all was done while the mercury was rising until it was approaching the highest point, when three up-and-down strokes were slowly made just previous to tapping. Where the flat or disc stirrer was employed stirring was carried out all the time the temperature was rising from the lowest to the highest point and at the rate of one complete (1 up- and 1 down-movement) in 2 seconds. This manipulation was done by hand and carefully timed.The cooling of the milk in the freezing-vessel was much more rapid when the disc stirrer was used than when the Hortvet stirrer was employed. It was found also that when the flat stirrer was used spontaneous freezing i.e. freezing without the introduction of a particle of ice took place rather frequently, rendering sometimes several attempts necessary before the desired amount of supercooling could be obtained. This never happened in those instances where the Hortvet stirrer was used. The freezing-point of water was taken with each of the two methods of stirring and identical readings were obtained. The results of the experiments are given in Table I. TABLE I E f e c t of diflerent methods of stirring No. of sample Hortvet stirrer A* Reading by hand-lens 20863 L.B.D.0.552 20867 L.B.D. 0.553 83583 Ws.D. 0.541 83589 Ws.D. 0.548 93438 Wgn.D. 0.533 53477 R.D. 0.541 53562 R.D. 0.546 83665 Ws.D. 0.550 83668 Ws.D. 0.550 76548 S.D. 0.538 76552 S.D. 0.548 76554 S.D. 0.539 Reading by levelled telescope Flat stirrer A 0.552 0.553 0.541 0-546 0.533 0-541 0.548 0.551 0.548 0.538 0.548 0.539 * A is the depression of the freezing-point of milk below that of water the reading of the It is of the same numerical thermometer being corrected for zero-point and irregularities of bore. value as the freezing-point but opposite in sign 162 STUBBS THE HORTVET FREEZING-POINT PROCESS FOR THE EXAMINATION It will be seen from the above table that in eight cases identical results were obtained by the use of the two different stirrers and that in the remaining cases small variations of not more than 0.002" were obtained.The explanation may be that the flat efficient stirrer used as described distributes quickly through the liquid the heat liberated on the formation of ice but at the same time the thorough stirring of the liquid increases the rate at which heat is abstracted from the contents of the freezing-tube. On the other hand when the Hortvet stirrer and technique are used, the particles of ice and liquid are not so quickly and thoroughly brought into contact with each other causing the heating-up to take place more slowly but the comparatively quiescent state of the outer layers of liquid nearest the cooling-bath hinders the process of abstraction of heat causing the resultant to be about the same in both cases.Another factor the accession of heat from the atmosphere, is probably not very different whichever method of stirring is employed and contributes its quota to both in much the same amount. There is one distinct difference which was invariably observed in the experi-ments described above. In the cases where the Hortvet stirrer was employed the time occupied by the mercury of the thermometer in rising from the lowest to nearly the highest point was definitely greater than the corresponding period when the efficient stirrer was used. This time measured by means of a stop-watch from the onset of freezing until tapping was carried out was in the case of the Hortvet technique about 90 seconds and with the flat stirrer about 30 seconds; that is about three times as long in the one case as in the other.The obvious explanation of this would appear to be that vigorous stirring by exposing quickly fresh surfaces of ice and liquid to each other increases the rate of heating while the comparative slowness with which mixture must take place where there is practically no stirring has the opposite effect. Monier-Williams6 suggests that " in the Hortvet apparatus steadiness of temperature at the freezing-point is secured by a fortunate oversight in the matter of stirring." But may it not be that Hortvet has made an attempt more or less successful if the above experiments are taken as an indication to diminish the action of the cooling-bath during the time freezing is in operation without the removal of the alcohol from the jacket surrounding the freezing-tube and so to arrange matters that the mercury column remains constant at the observed freezing-point sufficiently long to enable several tappings and readings to be made? It is suggested that he may have intentionally avoided energetic stirring in order to secure a longer period of rest of the mercury than would otherwise have been the case.There can be no doubt that he aspired to produce an apparatus which would be capable of giving results with a minimum of manipulation and one which would therefore be suitable for routine use. If in the process the alcohol need not be removed and a satisfactory result can still be obtained for the freezing-point it is a very definite recommendation for the adoption of non-removal in a routine process.The reduction in the amount of manipulation and the saving of time consequent on the non-removal of alcohol, will be acknowledged it is confidently thought by all who have had experience of the two methods when undertaking the examination of a number of milks. This result was unexpected O F MILK CORRECTION FACTORS AND THE INFLUENCE O F STIRRING I 153 There was nothing in these experiments to warrant any suggestion that the use of a flat efficient stirrer would be preferable to that of the standard Hortvet pattern used according to the Hortvet technique with possibly the slight variation suggested below. (2) The Hortvet stirrer-comparison between its use as prescribed in the A.O.A.C.In this series of experiments I employed the Hortvet stirrer throughout, comparing the effects of using it as prescribed in the A.O.A.C. regulations and also continuously while warming-up by means of the latent heat of formation of ice was in progress. It has been shown that vigorous stirring and practically no stirring gave the same or nearly the same readings for the freezing-point but, since two different types of stirrers were used there still remained the question if, when using the Hortvet stirrer different rates of manipulation would affect the results. There appeared too to be another reason which would justify the carrying out of this comparison. It was noticed during the work described in the previous section that the rate at which the mercury "approached" the highest point as judged by the use of a hand-lens after freezing had been induced was at first rapid and then gradually became slower and slower especially when the Hortvet technique was being followed and that the last 0.035" in that case took about 45 seconds compared with the whole time of rising of about 90 seconds-that is, half the period was taken by the last 0.035".The watching for the highest point reached is therefore apt to become tedious and some considerable practice is desirable because the column rises so slowly. It might be an advantage if this time could be shortened which it was thought might possibly happen if stirring were resorted to during the time the temperature was rising. It was therefore decided to carry out the work described below comparing the effects of continuous stirring with those of the procedure laid down in the Hortvet technique.Both varieties of stirring were practised on the same quantity of milk the sequence of the two methods being alternated in consecutive experiments. The supercooling was practically the same in every case; the greatest difference in the experiments on any one milk did not exceed 0.02". Table I1 gives the results. The freezing-point of water was taken with the two methods of stirring and identical readings were obtained. It will be seen from this table (p. 154) that the results are in close agreement, and in no case differ by more than 0.002" an amount so small that it cannot be regarded as significant. There was observed however as in the case where two different types of stirrers were used a difference in the time required by the mercury column to rise, after freezing had begun to nearly the highest point when tapping was needed.With the Hortvet method this period is about 90 seconds and with continuous stirring roughly 60 seconds and for the last 0-035" or so about 45 and 21 seconds respectively. Although the difference between the two latter figures is only 24 seconds it is very noticeable in working and the shorter time is a distinct advantage in judging the attainment of the nearly stationary position. It might, regulations and its continuous use 154 MIDDLETON TESTS FOR ELEMENTS I N ORGANIC COMPOUNDS TABLE I1 Comparison of the e$ect of digerent methods of using the Hortvet stirrer No. of sample Hortvet’s method Continuous stirring A A Reading by hand-lens 53479 R.D. 0.535 0.536 25321 H.B.D. 0.535 0.537 960 Wes though ton 0.542 0.542 970 J J 0.547 0-547 973 I J 0.536 0.537 30669 C.D. 0.550 0.551 76547 S.D. 0.540 0.542 Reading by levelled telescope 76549 S.D. 0.539 0.539 76550 S.D. 0.539 0.537 25428 H.B.D. 0.543 0.542 25430 H.B.D. 0.532 0.532 25433 H.B.D. 0.541 0-539 worthy of consideration whether the Hortvet technique should be to permit of a certain amount of stirring during the ascent of the therefore be altered so as mercury column. REFERENCES 1. 2. G. W. Monier-Williams ANALYST 1933 58 254. 3. 4. 5. ANALYST 1933 58 318. 6. ANALYST 1934 59 592. 7. G. W. Monier-Williams Food Reports 1914 KO. 22 p. 22. J. Hortvet J . I n d . Eng. Chem. 1921 13 200. Journal of the Association of Oficial Agricultural Chemists 1922-3 6 264. G. W. Monier-Williams ANALYST 1933 58 260. PARTS I1 AND I11 TO FOLLOW

ISSN:0003-2654    

DOI:10.1039/AN9356000147

出版商:RSC    

年代:1935

数据来源: RSC

摘要:

WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock. Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent. Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it.In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.

ISSN:0003-2654    

DOI:10.1039/AN9356000154

出版商:RSC    

年代:1935

数据来源: RSC

摘要:

WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock. Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent. Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it.In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.

ISSN:0003-2654    

DOI:10.1039/AN9356000158

出版商:RSC    

年代:1935

数据来源: RSC

摘要:

WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock. Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent. Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it.In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.

ISSN:0003-2654    

DOI:10.1039/AN9356000160

出版商:RSC    

年代:1935

数据来源: RSC

摘要:

WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock. Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent. Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it.In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr.E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent. Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it.In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper. Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness.He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper. Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness.He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr. E.M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country.Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper. Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.

ISSN:0003-2654    

DOI:10.1039/AN9356000163

出版商:RSC    

年代:1935

数据来源: RSC

摘要:

WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock. Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent. Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it.In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given. However, potatoes had been given to horses in limited quantities without bad results.Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.

ISSN:0003-2654    

DOI:10.1039/AN9356000170

出版商:RSC    

年代:1935

数据来源: RSC

摘要:

WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock. Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent. Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it.In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes.Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.WILLIMOTT AN INVESTIGATION OF SOLANINE POISONING 439 DISCUSSION The PRESIDENT remarked that it seemed somewhat strange that potatoes in certain states (old potatoes, green potatoes, etc.) were often described as highly toxic to stock.Many hundreds of tons had been used as stock feed, and he had never actually known of any stock poisoning. Of course, it could be argued that the potatoes used for feeding were often cooked, and much of the solanine dissolved out, but, on the other hand, a large number of these potatoes were used uncooked, and, therefore, stock did consume this vegetable with its full content of solanine, and, so far as he knew, without detriment. During the war a circular was issued, stating that potatoes were an injudicious feed for horses, and setting out the maximum amount that should be given.However, potatoes had been given to horses in limited quantities without bad results. Mr. C. E. SAGE said that cases of solanine poisoning were not infrequent, but he knew of no fatal one, caused by eating the bright red berries of Solanum dulcamara, which grew plentifully in this country. Solanum nzgrum, which had white flowers and black fruits, were sometimes eaten by country children, but he had never met with any casualties. Until recently the fruits of Solanum carolinense were used in America for the preparation of a tincture for medicinal use. I t grew plentifully as a weed in the Southern States, and the orange-coloured fruits were known as Sodom apples. The alkaloids, solanine and solanidine, existed in the fruits, and, as the negroes had used it for a long time as a remedy for falling sickness, the alkaloid could not be particularly toxic, although it was undoubtedly potent.Solanum chenopodium was a native of Queensland, and some thirty years ago he had isolated the alkaloid solanine from it. In Brazil, S. aculeatissimum was the plant yielding Sodom apples. It also contained solanine. With all these sources of solanine, and with potatoes and tomatoes containing it, there seemed to be no great danger from its toxicity. The leaves of S. nigrum were boiled and eaten in the Hawaii Islands, and the fruits known as “fox’s grapes’’ could be eaten in small quantities without any harmful effects. With sprouting potatoes it did not seem beyond the bounds of possibility that some product of decomposition might have caused the illness of people recorded in the paper.Mr. W. PARTRIDGE said that his only experience in the determination of solanine was in connection with a case in which it was alleged that potatoes had been tampered with and had caused illness. He had used the Meyer process, as outlined by Harris and Cockburn (ANALYST, 1918,43, 133) , but with the improve- ments (including the correction for solubility in ammonia wash-water) of Borner and Mattis (ANALYST, 1924, 49, 284). The potatoes in question, substantial areas of which were green, contained 19 mgrms. of solanine per 100 grms. Taking the attitude that normal potatoes contained about 2 mgrms., and never niore than 8 mgrms. per 100 grms., and that 25 mgrms. per 100 grms. were known to be dangerous, he had felt justified in associating the symptoms, minor though they were, with green potatoes. Mr. E. M. HAWXINS remarked that there seemed to be something in the wisdom of old-fashioned country folk. Thirty years ago when, fresh from the town, he went to live in a rural district, the old country folk instructed him that a potato which was allowed to get green through exposure above the earth was likely to be dangerous to human beings and to animals, and he, therefore, never used them. He thought it significant, in the Glasgow case, that more solanine was contained in potatoes which were green from exposure to sunlight than in the white tubers, and the paper certainly bore out this same contention.

ISSN:0003-2654    

DOI:10.1039/AN9356000173

出版商:RSC    

年代:1935

数据来源: RSC