O-methyloxime Derivatives Research Articles

Androst-4-ene-3,17-dione-4-14C Metabolism by the Homogenates of the Chicken Uropygial Gland I: Antibiotic Concentrations Necessary for Inhibition of Bacterial Growth

Supernatant fluid obtained from homogenates of chicken uropygial gland was incubated with androst-4-ene-3,17-dione-4-14C in the presence of penicillin and streptomycin. Two metabolic products were isolated and identified by using preliminary thin-layer chromatography followed by gas chromatography of the free metabolites, trimethylsilyl ethers, o-methyloxime derivatives, and double derivatives on 1 percent SE-30 and 1 percent neopentyl glycol succinate (NGS) columns. Crystallization to constant specific activity was also used for the identification of the metabolites. The metabolites identified were 3α-hydroxy-5α-androstane-17-one and 5α-androstane-3α,17β-diol. The isolated organisms from the supernatant fluid were highly susceptible to the activity of the antibiotics added to the incubation mixture for metabolic activity. The minimal concentrations of the antibiotics required to inhibit bacterial growth under the experimental conditions of this investigation were determined.

Testosterone metabolism by the chicken uropygial gland

Homogenates of chicken uropygial glands were incubated with testosterone-4-C 14 in a phosphate-buffer at 37°C for 24 hours. Three metabolic products of testosterone were identified by using preliminary thin layer chromatography, followed by gas chromatography of the free metabolites, their trimethylsilyl ethers, O-methyloxime derivatives and their double derivatives on one percent SE-30 and one percent NGS columns. The steroid metabolites were also identified by crystallization to constant specific activity. The metabolites identified were: 3α-hydroxy-5α-androstane-17-one; 5α-androstane-3, 17-dione, and 5α-androstane-3α,17β-diol.

A double isotope derivative assay for progesterone and 20α-hydroxypregn-4-en-3-one

A double isotope derivative method for the estimation of progesterone and 20α-hydroxypregn-4-en-3-one in tissues and biological fluids is described. Progesterone is enzymatically reduced and measured as 20β-hydroxypregn-4-en-3-one. 14C-steroids are used as indicators, and acetic- 3H anhydride is used as the derivatizing reagent to estimate mass. Extraneous tritium, not associated chemically with purified steroid acetates is removed by combinations of absorption and partition-type paper Chromatographie techniques. Specificity is enhanced through formation of the o-methyloxime derivatives of the 20-acetoxy-pregn-4-en-3-ones. critical evaluation of the method is included giving attention to its specificity, sensitivity, precision and accuracy. The method is suitable for the estimation of from 0. 05 to 1. 0 μg progesterone with an error of 10% or less, and 0. 005 μg is estimated with an error of about 30%. A method for calculating endogenous steroid is presented which relies on a comparison between the 3H/ 14C ratios of the isolated steroid acetate and the acetylated indicator steroids. By this operation a more meaningful evaluation of the sample blank is possible and specificity can be more rigorously assessed. Analyses of progesterone and 20α-hydroxypregn-4-en-3-one are reported for peripheral plasma and endocrine tissues taken from pregnant and pseudopregnant rats and pregnant rabbits.

Testosterone metabolism by human male mammary skin

Tissue slices of human male mammary skin were incubated with testosterone in a Krebs-Ringer phosphate buffer at 37°C for six hours. Four metabolic products of testosterone were identified by preliminary chromatography of the incubation extracts on silica gel columns, followed by gas chromatography of the free metabolites, their trimethylsilyl ethers, O-methyloxime derivatives and double derivatives on one percent SE-30 and one percent NGS columns. The metabolites identified were: 5α-androstane-3α-o1,17-one; 5α-androstane-3, 17-dione, androst-4-ene-3, 17-dione and 5β-androstane-3α-o1, 17-one.