The hydrogenation of γ-linolenic acid by pure cultures of two rumen bacteria

Abstract

Two species of rumen bacteria that have been previously shown to partially hydrogenate alpha-linolenic acid have been examined for their ability to hydrogenate gamma-linolenic acid. Free gamma-linolenic acid is hydrogenated in vitro to stearic acid by a rumen Fusocillus sp. (N.C.I.B. 11026), but only to cis, trans-octadec-6,11-enoic acid by a Butyrivibrio sp. The sequential hydrogenations are preceded by a delta 12-cis-delta 11-trans isomerization identical with that observed in the hydrogenation of alpha-linolenic acid and linoleic acid.