C-10(19) oxidation of vitamin D by anaerobic gastrointestinal bacteria

Abstract

Importance and implications Bile Cholesterol Other biologically important steroids 28 Vitamin D Vitamin D Importance and implications Metabolism Biological activity Enterohepatic cycling of vitamin D Requirements and toxicity SECTION I. FACTORS AFFECTING THE PRODUCTION OF 5(E) 19-NOR-lO-KETO-VITAMIN D3 BY RUMEN BACTERIA 46 MATERIALS AND METHODS 49 General 49 Steroids 49 Enzymes 50 Extraction and Chromatography 50 Preparation of Media 51 Assay Conditions 52 iii Rumen Fluid Studies 52 Oxygen studies 53 Preincubation treatments Mixed Culture Studies Filtration Time study Glucose inhibition Isolation of Clostridium sp. Strain A264 Pure Culture Studies Glucose inhibition studies Cysteine Studies RESULTS Rumen Fluid Studies BHI Broth Culture Studies DISCUSSION 62 LITERATURE CITED SECTION II. THE BIOLOGICAL ASSESSMENT OF VITAMIN Dg METABOLITES PRODUCED BY RUMEN BACTERIA 80 Biological Evaluation Preparation "of Bacterial Culture Medium Isolation of Clostridium sp. Strain A264 Rumen Fluid Assay Conditions Extraction and Chromatography RESULTS 91