title: The biohydrogenation of alpha-linolenic acid and oleic acid by rumen micro-organisms.
abstract: 1. alpha-[U-(14)C]Linolenic acid was incubated with the rumen contents of sheep and the metabolic products were characterized by thin-layer chromatography, gas-liquid chromatography and absorption spectroscopy in the ultraviolet and infrared. 2. A tentative scheme for the biohydrogenation route to stearic acid is presented. The main pathway is through diconjugated cis-cis-cis-octadecatrienoic acid, non-conjugated trans-cis (cis-trans)-octadecadienoic acid and trans-octadecenoic acid, but other pathways are apparent. 3. Washed rumen micro-organisms possessed only a limited capacity to hydrogenate alpha-linolenic acid and oleic acid but the rate was greatly stimulated by a factor(s) present in the supernatant rumen liquor. 4. Pure cultures of Clostridium perfringens, Streptococcus faecalis, Escherichia coli and a coliform organism isolated from sheep faeces possessed negligible ability to hydrogenate unsaturated fatty acids compared with a mixed population of rumen micro-organisms. Butyrivibrio fibrisolvens slowly converted linoleic acid into octadecenoic acid.
mesh_terms: D000818:Animals; D002849:Chromatography, Gas; D002855:Chromatography, Thin Layer; D003016:Clostridium perfringens / Q000378:metabolism*; D013293:Enterococcus faecalis / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D005228:Fatty Acids, Essential / Q000378:metabolism*; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000378:metabolism*; D009829:Oleic Acids / Q000378:metabolism*; D012417:Rumen / Q000378:metabolism*; D012756:Sheep; D013057:Spectrum Analysis
chemical_list: D005228:Fatty Acids, Essential; D009829:Oleic Acids