66 ABSTRACTS OF CHEMICAL PAPERS. P h y s i o l o g i c a l Chemistry. Sugar in the Blood with Reference to Nutrition. By J. SEEGEN (PJliiger’s Archiu, 39, 121--131).-Experiments on dogs hare shown (Abstr., 1886, 382 and 411) that the percentage of sngar is always approximately twice as great in the blood of the hepatic as in the blood of the portal vein during various carbohydrate diets and during long periods of inanition, also that peptone is probably the chief constituent from which the liver forms sugar under normal conditions. The sugar formed in one day during starvation is far in excess of the total glycogen present in the body. Further experiments have been made on dogs fed with a diet of meat only, of fat with a minimal quantity of meat, and in some instances with fat only.The general result is the same as in previous experiments, namely, that the percentage of sugar in the blood leaving the liver is double that of the blood ou entering. The total amount of sugar in the blood as well as the difference between the percentages in the bloodPBTStOLOGI&iL CHEMISTRY. 67 oh cntering and leaving the liver is greater with a meat diet than arty other. The most striking result is the continued formation of sagar during an almost exclusively fat diet. It might be supposed that this is due to prote’id decomposition, but a determination of the nitrogen excreted during the feeding was quite insufficient to account for the increase. The amount of blood passing through the liver of dogs of 10 to 12 kilos is not less than 200 litres in the 24 hours.The mean difference in thk percentage of sugar of the blood on entering and leaving the liver is 0.1 per cent., consequently about 200 grams of sugar would he foi-med in 24 hours. During the f a t diet, the amount of nitrogen excreted daily was on an average 15 grams, corresponding to 100 grams of prote’id, a quantity quite insufficient to furnish 200 grams of sugar, even supposing that none of the carbon of the proteid be utilised for the formation of urea. The conclusion drawn from these experiments is that the liver has the power of forming sugar from fat. This would satisfactorily explain the constant formation of sugar during starvation, for Voit has shown that an animal during starvation loses 97 per cent. of its fat, and only 30 per cent.of its muscular substance. The chief results of the author’s experiments may be thus summed up :- 1st. The blood of the hepatic vein is without exception richer in sugar tlinn the blood of the portal vein. 2nd. The new formed sugar does not depend on the sugar and carbohydrates ingested with the food. 3rd. The glycogen of the liver is not concerned in the formation of sugar. 4th. Albumin and fat are the materials from which the liver forms sugar. J. P. L. Power of the Liver to Form Sugar from Fat. By J. SEEGEN (P’iiger’s Arcltiv, 39, 132--142).-1t has been previously shown that small pieces of freshly excised liver in the presence of defibriaated blood have the power of converting peptone info sugar (Abstr., 1886, 382). By a similar series of experiments, the author has proved that the liver cells can under the same conditions convert fat into sugar, thus confirming the conclusion he arrived at from his experi- ments on feeding dogs on a diet consisting exclusively of fat (pre- ceding Abstract).For each experiment, 50 grams of finely cut liver excised from a recently killed dog was mixed with 60 to 80 C.C. of freshly defibri- nated blood and placed in a, large flask; to this mixture various emulsions of vegetable oils were added. The flask and contents were maintained for 5 or 6 hours a t 35’ to 40°, and a constant stream of air was drawn through tJhe mixture of blood by means of an aspirator. The average increase in the percentage of sugar was found to be 50 per cent. A further series of experiments proved that both constitpnts of a fat, that is both glycerol and the fatty acid, are alike capable of beiug converted into sugar by the liver.Control experiments we1.e made in every instance. J. P. L. f 268 ABSTRACTS OF CHEMICAL PAPERS. hportance of Ammonia for the Format:on of Glycogen in tle Liver of the Rabbit. By F. ROHMANN (Pjiiger’s Archiv, 39, 21--53).-Aspmagine and glycocine given with a carbohydrate diet inorease the amount of glycogen formed in the liver to a marked extent ; this increase i8 more pronounced with asparagine than with glymcinc. On account of its slight solubility, asparagine is probably not absorbed unchanged, but undergoes decomposition with formation of ammonia. Ammonium carbonate given with the game diet increases the glycogenin a still more maked manner, but ammonia in the form of lactate seems t o be inert.As sodium carbonate and hydrogen carbonate have no effect, ammonium carbonate does not exert its influence by reason of its alkalinity. As a possible explanation, the author suggests that the ammonia arid a carbohydrate entming +he liver cells together may form a new compound which will split into glycogen on the one hand and a nitro- genised product on the other, for instance, urea. Feeding and Development of Silkworms. By 0. KFLLNER (Landw. Versuchs-Stat., 1886, 38€-392).-This article contailis an account of experiments which are a continuation of those previously detitilecl (Abstr., 1884, 1202). The research was commenced with the view of determining whnf quantity of food was necessary for the f u l l and healthy development of the worm, with the largest subsequent supply of silk.Without entering into the details of feeding, &c., all of which are fully given in tables, i t will be sufficient to give the find results. Every increase of growth requires an increase in the food, but this increase in food is not commensurate with the growth, being very much higher ; the weaker the illsect is before envelop- ment, the greater will be the loss during metamorphosis, by respira- tion, &c. A poorly fed and dereloped cakerpillar produces a lower yield of valuable silk than those which are well and largely fed, and will con- tain iiiore nitrogenous and mineral matter, whilst the well-fed in+ect will be richer in fat and other non-nitiaogenous matter.J. P. L. E. W. P. Isethionic Acid in the Body, and Thiosulphuric Acid in the Urine. By E SALKOWSKI (PJliig~r’s Archia, 39, 209--222).-1n a former paper (Virchow’s Archiv, 66, 31.5)’ the author stated that in the dog the admillistration of sodium isethionate produced an in- crease of sulphuric acid in the urine, but tbat thiosulphuric a d was under all circumstances absent. Heffter (P’iiger’s Archiu, 38, 476) states however, that sulphuric acid is not formed from isethionic acid, but that the greater part (78 per cent.) of the latter acid leaves the body as thiosalphuric acid, and a ~meller portion (22 per cent.) in Rome undiscovered manner. Heffter himself explains the discrepancy by supposing it to be due to the differerice in diet during the inyestiga- tion, Heffter using meat, not bread and milk as in Salkowski’s earlier e .periments.The present research is a, rehvestigation of the subject : a dog wauPIIY‘EIOLOGICAL CHEMISTRY. 69 fed on a fixed meat diet, and for three days 3 grams of sodium isethonate was given per diem. The results are shown inithe fullowing table :- Nitrogen Sulphurio wid ray. Diet. in urine. in urine. 1 Meat 12-22 3-20 2 Do. 12.49 3.15 3 Do. 12.49 2.9 7 4 3 gr. of drug added 12-49 3 83 5 Do. 12.23 4.65 6 Do. 12.25 4.99 7 Meat 12.04 3.40 8 Do. 11.63 2.89 9 Do. 11-49 3.16 This table shows that whereas the nitrogen output remains cou- stant, the amount of sulphates is increased ; the increase could there- fore not have been due to increased metabolism of protkds; it is therefore all due to the isethionic acid, and it is found from the foregoing numbers, that 30 per cent.of the isethionic acid must have become oxidised into sulphuric mid. By comparing the intensity of the sulphuretted hydrogen reaction, it was found also that the amount of thiosnlphnric acid in the urine was slightly increased. The amount of this acid in the urine was estimated also by its reducing action on potassium permanganate; the increase during the days when the drug was given, show theoretically that 13.4 per cent, of the sulphur of the isethionic acid pass out of the body in tohe form of thiosulphuric acid, a figure which is shown by control experiments to be too high, as the urine contains other easily oxidisable substances. The question as to what becomes of the re- mainder of thesulphur is not entered into.There seemsalso to be no way of reconciling the present results with those obtained by Heffter. The aromatic sulphonic acids pafis out unchanged in the urine, no thiosulphates being formed; this also is contradictory to the state- ments of Heffter. W. D. H. Trypsin in Urine. By H. LEO (Pjiigw’s Archiv, 39, 246- 264) .-Since the publication of the author’s paper (Abstr., 1886, 381) in which he showed that trypsin did not exist in the urine, Gehrig (P’iiger’s Archiv, 38, 35) states he has found trypsin in the urine ; pieces of fibrin stained with magdala-red, soaked in urine, and trailsferred to 1 per cent. soda solution undergo digestion in a few hours ; this cannot be due to putrefaction as it is so rapid ; it is how- ever prevented by the admixture of t h p o l mlth the digesting mixture; this is explained by saying that thymol hinders pancreatic digestion.The present research is a reinvestigation of the subject, the urine of healthy men and dogs being employed. I t is found that thymol does not hinder pancreatic digestion. A very weak solution of the trpptic ferment was prepared by adding a drop of glycerol extract of pancreas to a litre of water. This excited no digestive action on fibrin. After pieces of fibrin had been soaked in it for70 ABSTRACTS OF CHEMICAL PAPERS. 24 hours, however, and then transferred to a 1 per cent. soda solution they underwent digestion, as they had absorbed the ferment. With the urine, however, no such result ever occurred ; that is, urine, if it contains trypsin at all, contains a less amount than the weak solution of it obtained hy adding.a drop of extract of pancreas to a litre of water.W. I). H66 ABSTRACTS OF CHEMICAL PAPERS.P h y s i o l o g i c a l Chemistry.Sugar in the Blood with Reference to Nutrition. By J.SEEGEN (PJliiger’s Archiu, 39, 121--131).-Experiments on dogs hareshown (Abstr., 1886, 382 and 411) that the percentage of sngar isalways approximately twice as great in the blood of the hepatic as inthe blood of the portal vein during various carbohydrate diets andduring long periods of inanition, also that peptone is probably thechief constituent from which the liver forms sugar under normalconditions. The sugar formed in one day during starvation is far inexcess of the total glycogen present in the body.Further experiments have been made on dogs fed with a diet ofmeat only, of fat with a minimal quantity of meat, and in someinstances with fat only.The general result is the same as in previous experiments, namely,that the percentage of sugar in the blood leaving the liver is doublethat of the blood ou entering.The total amount of sugar in theblood as well as the difference between the percentages in the blooPBTStOLOGI&iL CHEMISTRY. 67oh cntering and leaving the liver is greater with a meat diet than artyother.The most striking result is the continued formation of sagar duringan almost exclusively fat diet. It might be supposed that this is dueto prote’id decomposition, but a determination of the nitrogen excretedduring the feeding was quite insufficient to account for the increase.The amount of blood passing through the liver of dogs of 10 to12 kilos is not less than 200 litres in the 24 hours.The mean differencein thk percentage of sugar of the blood on entering and leaving theliver is 0.1 per cent., consequently about 200 grams of sugar wouldhe foi-med in 24 hours. During the f a t diet, the amount of nitrogenexcreted daily was on an average 15 grams, corresponding to 100grams of prote’id, a quantity quite insufficient to furnish 200 gramsof sugar, even supposing that none of the carbon of the proteid beutilised for the formation of urea.The conclusion drawn from these experiments is that the liver hasthe power of forming sugar from fat.This would satisfactorilyexplain the constant formation of sugar during starvation, for Voithas shown that an animal during starvation loses 97 per cent. of itsfat, and only 30 per cent. of its muscular substance.The chief results of the author’s experiments may be thus summedup :-1st. The blood of the hepatic vein is without exception richer insugar tlinn the blood of the portal vein.2nd. The new formed sugar does not depend on the sugar andcarbohydrates ingested with the food.3rd. The glycogen of the liver is not concerned in the formation ofsugar.4th. Albumin and fat are the materials from which the liverforms sugar. J. P. L.Power of the Liver to Form Sugar from Fat. By J. SEEGEN(P’iiger’s Arcltiv, 39, 132--142).-1t has been previously shown thatsmall pieces of freshly excised liver in the presence of defibriaatedblood have the power of converting peptone info sugar (Abstr.,1886, 382).By a similar series of experiments, the author has provedthat the liver cells can under the same conditions convert fat intosugar, thus confirming the conclusion he arrived at from his experi-ments on feeding dogs on a diet consisting exclusively of fat (pre-ceding Abstract).For each experiment, 50 grams of finely cut liver excised from arecently killed dog was mixed with 60 to 80 C.C. of freshly defibri-nated blood and placed in a, large flask; to this mixture variousemulsions of vegetable oils were added. The flask and contents weremaintained for 5 or 6 hours a t 35’ to 40°, and a constant stream ofair was drawn through tJhe mixture of blood by means of an aspirator.The average increase in the percentage of sugar was found to be50 per cent.A further series of experiments proved that both constitpnts of afat, that is both glycerol and the fatty acid, are alike capable of beiugconverted into sugar by the liver.Control experiments we1.e made in every instance.J.P. L.f 68 ABSTRACTS OF CHEMICAL PAPERS.hportance of Ammonia for the Format:on of Glycogen intle Liver of the Rabbit. By F. ROHMANN (Pjiiger’s Archiv, 39,21--53).-Aspmagine and glycocine given with a carbohydrate dietinorease the amount of glycogen formed in the liver to a markedextent ; this increase i8 more pronounced with asparagine than withglymcinc.On account of its slight solubility, asparagine is probablynot absorbed unchanged, but undergoes decomposition with formationof ammonia.Ammonium carbonate given with the game diet increases theglycogenin a still more maked manner, but ammonia in the formof lactate seems t o be inert.As sodium carbonate and hydrogen carbonate have no effect,ammonium carbonate does not exert its influence by reason of itsalkalinity.As a possible explanation, the author suggests that the ammoniaarid a carbohydrate entming +he liver cells together may form a newcompound which will split into glycogen on the one hand and a nitro-genised product on the other, for instance, urea.Feeding and Development of Silkworms. By 0. KFLLNER(Landw. Versuchs-Stat., 1886, 38€-392).-This article contailis anaccount of experiments which are a continuation of those previouslydetitilecl (Abstr., 1884, 1202).The research was commenced with theview of determining whnf quantity of food was necessary for the f u l land healthy development of the worm, with the largest subsequentsupply of silk. Without entering into the details of feeding, &c., allof which are fully given in tables, i t will be sufficient to give the findresults. Every increase of growth requires an increase in the food,but this increase in food is not commensurate with the growth,being very much higher ; the weaker the illsect is before envelop-ment, the greater will be the loss during metamorphosis, by respira-tion, &c.A poorly fed and dereloped cakerpillar produces a lower yield ofvaluable silk than those which are well and largely fed, and will con-tain iiiore nitrogenous and mineral matter, whilst the well-fed in+ectwill be richer in fat and other non-nitiaogenous matter.J.P. L.E. W. P.Isethionic Acid in the Body, and Thiosulphuric Acid in theUrine. By E SALKOWSKI (PJliig~r’s Archia, 39, 209--222).-1n aformer paper (Virchow’s Archiv, 66, 31.5)’ the author stated thatin the dog the admillistration of sodium isethionate produced an in-crease of sulphuric acid in the urine, but tbat thiosulphuric a d wasunder all circumstances absent. Heffter (P’iiger’s Archiu, 38, 476)states however, that sulphuric acid is not formed from isethionic acid,but that the greater part (78 per cent.) of the latter acid leaves thebody as thiosalphuric acid, and a ~meller portion (22 per cent.) inRome undiscovered manner. Heffter himself explains the discrepancyby supposing it to be due to the differerice in diet during the inyestiga-tion, Heffter using meat, not bread and milk as in Salkowski’s earliere .periments.The present research is a, rehvestigation of the subject : a dog waPIIY‘EIOLOGICAL CHEMISTRY.69fed on a fixed meat diet, and for three days 3 grams of sodiumisethonate was given per diem. The results are shown inithe fullowingtable :-Nitrogen Sulphurio widray. Diet. in urine. in urine.1 Meat 12-22 3-202 Do. 12.49 3.153 Do. 12.49 2.9 74 3 gr. of drug added 12-49 3 835 Do. 12.23 4.656 Do. 12.25 4.997 Meat 12.04 3.408 Do.11.63 2.899 Do. 11-49 3.16This table shows that whereas the nitrogen output remains cou-stant, the amount of sulphates is increased ; the increase could there-fore not have been due to increased metabolism of protkds; itis therefore all due to the isethionic acid, and it is found fromthe foregoing numbers, that 30 per cent. of the isethionic acidmust have become oxidised into sulphuric mid. By comparingthe intensity of the sulphuretted hydrogen reaction, it was foundalso that the amount of thiosnlphnric acid in the urine was slightlyincreased. The amount of this acid in the urine was estimated alsoby its reducing action on potassium permanganate; the increaseduring the days when the drug was given, show theoretically that13.4 per cent, of the sulphur of the isethionic acid pass out of thebody in tohe form of thiosulphuric acid, a figure which is shown bycontrol experiments to be too high, as the urine contains other easilyoxidisable substances.The question as to what becomes of the re-mainder of thesulphur is not entered into. There seemsalso to be noway of reconciling the present results with those obtained by Heffter.The aromatic sulphonic acids pafis out unchanged in the urine, nothiosulphates being formed; this also is contradictory to the state-ments of Heffter. W. D. H.Trypsin in Urine. By H. LEO (Pjiigw’s Archiv, 39, 246-264) .-Since the publication of the author’s paper (Abstr., 1886,381) in which he showed that trypsin did not exist in the urine,Gehrig (P’iiger’s Archiv, 38, 35) states he has found trypsin in theurine ; pieces of fibrin stained with magdala-red, soaked in urine, andtrailsferred to 1 per cent. soda solution undergo digestion in a fewhours ; this cannot be due to putrefaction as it is so rapid ; it is how-ever prevented by the admixture of t h p o l mlth the digestingmixture; this is explained by saying that thymol hinders pancreaticdigestion. The present research is a reinvestigation of the subject,the urine of healthy men and dogs being employed. I t is found thatthymol does not hinder pancreatic digestion. A very weak solutionof the trpptic ferment was prepared by adding a drop of glycerolextract of pancreas to a litre of water. This excited no digestiveaction on fibrin. After pieces of fibrin had been soaked in it fo70 ABSTRACTS OF CHEMICAL PAPERS.24 hours, however, and then transferred to a 1 per cent. soda solutionthey underwent digestion, as they had absorbed the ferment. Withthe urine, however, no such result ever occurred ; that is, urine, if itcontains trypsin at all, contains a less amount than the weak solutionof it obtained hy adding.a drop of extract of pancreas to a litre ofwater. W. I).