摘要:

AbstractThe cell fragility method was used to investigate the muscle of cod that had been frozen and cold‐stored under various conditions. The results are compared with those obtained by the ‘soluble protein’ method, and the relationship between them is disc

ISSN:0022-5142    

DOI:10.1002/jsfa.2740130501

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractThe irradiation of liver slices with 2 MeV electrons at 0° had no effect upon the phospholipase or lipase activity of the tissue at doses less than 6 Mrad. Proteolytic activity was reduced at doses as low as 0.1 Mrad and was 50% inhibited at 3.0 Mard. Considerable proteolytic and lipolytic activity remained after irradiation with 40 Mrad

ISSN:0022-5142    

DOI:10.1002/jsfa.2740130502

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractThe influence of concentration and of time after treatment on knock‐down and recovery from the action of pyrethrum extract alone and with piperonyl butoxide at 2 : 1 and 1 : 5 w/w, was studied on house flies(Musca domesticaL.) by a measured drop method. The unanaesthetised flies, held by suction during dosing, were inspected after treatment at frequent intervals for 5 h. and once on the following day. The tests were done at 20† with the materials tested dissolved in n‐dodecane.Most of the flies treated with a fixed dose of pyrethrum extract alone or with piperonyl butoxide remained normal for a very short time (the latent period). The number of flies knocked down increased very rapidly during the knock‐down period and reached a maximum at the knock‐down end‐point. Past this point a proportion of the flies knocked down recovered, the rest died. The relative and absolute durations of each of these periods were influenced by the concentration of pyrethrins and the presence of piperonyl butoxide. The interval of time between treatment and knock‐down end‐point was the same (10 min.) over a wide range of concentrations when the flies were treated with pyrethrum extract alone, and the flies treated with the extract alone recovered rapidly after knock‐down end‐point. The synergist inhibited recovery, so that more flies died, increased the toxicity of the extract during knock‐down and prolonged the duration of knockdown. The influence of piperonyl butoxide, small initially, increased with the passage of time after treatment.Attention is drawn to some of the shortcomings of methods commonly used to compare the knock‐down

ISSN:0022-5142    

DOI:10.1002/jsfa.2740130503

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractThe knock‐down activities of pyrethrins I and II and cinerins I and II were studied on house flies (Musca domesticaL.) by a measured drop technique. Unanaesthetised flies held by suction during dosage were inspected at frequent intervals for 5 h. The tests were done at 20† with the materials tested dissolved in n‐dodecane.The relative toxicities of the materials, measured at ED50differed at different times after treatment; 4 min. and 2 h. after treatment they were, respectively : pyrethrum extract, 1.0, 1.0; pyrethrin II, 1.98, 1.58; cinerin II, 0.69, 0.51; pyrethrin I, 0.60, 1.07; cinerin I, 0.50, 0.64. The KD50end‐points were : pyrethrin II, 10 min.; cinerin II, 11 min.; pyrethrum extract, 13 min.; pyrethrin I, 17 min.; cinerin I, 20 min. At KD50end‐point the relative toxicities and the relative speeds of knock‐down (given in brackets) were: pyrethrum extract, 1.0 (1.0); pyrethrin II, 2.16 (1.30); pyrethrin I, 0.72 (0.76); cinerin II, 0.66 (1.18); cinerin I, 0.55 (0.65). The relative toxicities of pyrethrin II and cinerin II decreased with the passage of time after treatment because flies recovered sooner from them than from pyrethrin I and cinerin I.Possible reasons are discussed for the differences in the order of the relative toxicities of the constituents when determined by differ

ISSN:0022-5142    

DOI:10.1002/jsfa.2740130504

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractBy the application of reversed‐phase partition chromatography, the oil from the seeds ofHoloptelea integrifolia(Urticaceae) is found to contain the following acids : lauric 0.2%, myristic 3.5%, palmitic 35.1%, stearic 4.5%, arachidic 1.1%, behenic 0.4%, hexadecenoic 1.9% and oleic 53.3

ISSN:0022-5142    

DOI:10.1002/jsfa.2740130505

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractThe fatty acid composition of egg yolk lipids resulting from controlled dieting with sunflower seed oil and maize oil has been investigated by gas‐liquid chromatographic analysis with a β argon chromatograph. The results are compared with earlier work involving separation by fractional crystallisation and ester fractionation methods, and differences in composition are noted. The effect of dieting on fatty acid content has been re‐exam

ISSN:0022-5142    

DOI:10.1002/jsfa.2740130506

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractA two‐dimensional paper chromatographic method has been used for the separation and detection of all the known oestrogenic isoflavones and coumestrol in red clover. The presence of other isoflavone components in red clover is suggested. The concentrations of the individual oestrogenic constituents were determined by spectrophotometric measurement after separation by paper chromatography. Biochanin A has been found to be the predominant oestrogen in red clover, while formononetin (the other major isoflavone) is inactiv

ISSN:0022-5142    

DOI:10.1002/jsfa.2740130507

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY

ISSN:0022-5142    

DOI:10.1002/jsfa.2740130508

出版商:John Wiley&Sons, Ltd    

年代:1962

数据来源: WILEY