摘要:

Some characteristics of the system present in pancreatin responsible for the enzymatic esterification of ethanol with fatty acids were examined. Definite pH optima were found for different fatty acids in the pH range 5.5–6.1. At a relatively high ethanol level and with a low fixed fatty acid concentration at pH 6.1, the degree of esterification was oleic = linolenic > linoleic > arachidonic > myristic > palmitic > stearic. At various acid concentrations the same general order of specificity was observed but to differing extents. The physical state of dispersion of the fatty acid in the incubation medium appeared to be a major factor governing the fatty acid specificity for esterification of ethanol. Evidence for the possible occurrence of more than one enzyme activity functioning on fatty acid substrate in different dispersion states was obtained and discussed.

ISSN:0008-4018    

DOI:10.1139/o65-134

出版商:NRC Research Press    

年代:1965

数据来源: NRC

摘要:

The effect of norethandrolone (17α-ethyl-19-nortestosterone) on the epiphyseal cartilage of rachitic chicks was investigated in conjunction with the studies of vitamin D3effect on this tissue. Norethandrolone effected a significant decrease in the activity of hexosamine synthetase, but did not alter appreciably the levels of hexosamine or hydroxyproline, nor the activity of alkaline phosphatase.It was noted that norethandrolone exerted a powerful stimulation on the growth of combs of immature chicks. The increased weight of the combs was accompanied by a higher water content. The de-fatted and dried fraction of these combs had an elevated content of hexosamines, while the decrease in hydroxyproline content was noted only after a prolonged treatment with the steroid. Studies with radioactive tracers (Na2S35O4, NaOAc-1-C14) showed an increased rate of incorporation of these potential components of glycosaminoglycans in the de-fatted and dried fraction of the combs. In addition, norethandrolone enhanced the alkaline phosphatase activity in combs.

ISSN:0008-4018    

DOI:10.1139/o65-135

出版商:NRC Research Press    

年代:1965

数据来源: NRC

摘要:

Rabbits, mice, and dogs were injected with 1-aminocyclopentane-C14-carboxylic acid and the distribution of the drug was studied by tissue analysis. Concentration of the isotope was observed in mouse pancreas but not in that of dogs and rabbits.

ISSN:0008-4018    

DOI:10.1139/o65-136

出版商:NRC Research Press    

年代:1965

数据来源: NRC

摘要:

Preparations consisting mostly of γ- or β-globulin were obtained from a horse antiserum to diphtheria toxin by ammonium sulfate precipitation. These preparations were treated with papain and the digests separated on Sephadex G-100 columns. The γ-globulin digests were resolved into a major 3.4 S component and smaller minor components. The β-globulin digest contained similar fragments and, in addition, a major 5.0 S component. All fragments neutralized toxin, the most active being the β-globulin 5.0 S and 3.4 S fragments. The 3.4 S γ- and β-globulin fragments were univalent. The 5.0 S β-globulin fragment was divalent, and it could be reduced to 3.4 S subunits by treatment with 0.3 M2-mercaptoethanol.

ISSN:0008-4018    

DOI:10.1139/o65-137

出版商:NRC Research Press    

年代:1965

数据来源: NRC

摘要:

The distribution of P32-labelled Dipterex among different organs of the adult larva of the cotton leaf worm showed that the major radioactivity was translocated in hemolymph and gut. Dipterex was readily metabolized in vitro to give monodemethylated Dipterex which contributed to 91% of the acidic metabolites. Monomethylphosphate (about 9%) could also be identified as a metabolic product. The low toxicity of Dipterex toProdenialarvae is probably due to preferential methyl ester cleavage.

ISSN:0008-4018    

DOI:10.1139/o65-138

出版商:NRC Research Press    

年代:1965

数据来源: NRC

摘要:

The metabolism of P32-labelled Dipterex in rat brain homogenates has been investigated. The presence of four metabolites, three acidic and one nonacidic, has been demonstrated. Monodemethylated Dipterex and monomethylphosphate contributed to 37% and 7% of the total metabolite output respectively. The third acidic metabolite (16%) is believed to be 2,2,2-trichloro-1-hydroxyethyl phosphonic acid. The nonacidic compound has not yet been identified. The reaction of Dipterex with acetylcholine esterase has been found to be of bimolecular nature.

ISSN:0008-4018    

DOI:10.1139/o65-139

出版商:NRC Research Press    

年代:1965

数据来源: NRC

摘要:

Direct evidence for the hydrolysis of O-methyl ester linkage(s) of Dipterex in the rat has been obtained using Dipterex in which the two methyl groups are C14-labelled. Following a single injection (i.p.) of radio-Dipterex, about 60% of the C14activity was recovered, after 24 hours, in the expired air and in the urine. C14O2and C14-formate constituted about 50% of the recovered radioactivity. The contribution of P—OCH3cleavage to the detoxification of the insecticide has been discussed. A scheme for the fate of the methyl groups has been suggested.

ISSN:0008-4018    

DOI:10.1139/o65-140

出版商:NRC Research Press    

年代:1965

数据来源: NRC

摘要:

Hot alkaline hydrolysis of an organic soil followed by multiple unidimensional paper chromatographic analyses have affordedp-coumaric, ferulic, sinapic, and 3,5-dihydroxybenzoic acids. It is suggested that part of the phenolic acids may be derived from non-lignin plant materials incorporated into the humus.

ISSN:0008-4018    

DOI:10.1139/o65-141

出版商:NRC Research Press    

年代:1965

数据来源: NRC

摘要:

Reoplex 400 coated Chromosorb W (10% w/w on Chromosorb W, 60–80 mesh) columns (15 inches ×inch) were used with an Aerograph A-90-P2 gas chromatograph. Complete separations and symmetrical peaks of the methyl esters of lactic, glycollic, oxalic, malonk, succinic, malic, aconitic, tartaric, citric, isocitric, and fumaric acids and isocitric acid lactone were obtained by programming the temperature at 4 °C/minute from 55 °C to 175 °C. Single acids could easily be assayed at an isothermal temperature. A linear relationship was obtained between the areas recorded and the quantities of acid injected. There was no consistent relationship between molecular species and response, so that the instrument was calibrated for each individual acid. The analyses of some plant materials for organic acids are presented.

ISSN:0008-4018    

DOI:10.1139/o65-142

出版商:NRC Research Press    

年代:1965

数据来源: NRC

摘要:

DDT is metabolized by rat liver microsomes to a phenolic compound and to a reduced derivative similar to DDD. When rats were injected intraperitoneally with DDT, the microsomal DDT-metabolizing activity was greatly increased. This effect was blocked by the administration of puromycin. DDT administration also increases the content of liver microsomal protein. The results show that the insecticide probably increases the DDT-metabolizing activity of mammalian liver by inducing enzyme synthesis.

ISSN:0008-4018    

DOI:10.1139/o65-143

出版商:NRC Research Press    

年代:1965

数据来源: NRC