Biosynthesis of linoleic acid from 1-C14-cis-2-octenoic acid by the laying hen*

Abstract

A white leghorn hen was given 0.2 mc of 1-C14-cis-2-octenoic acid in one 1.05-g dose, and five eggs laid subsequently were collected. Linoleic acid isolated from the eggs, both as the tetrabromide and by preparative gas-liquid chromatography, was found to be radioactive. This was proven to be octadeca-9,12-dienoic acid by characterizing the products of oxidation—caproic and azelaic acids, and 3 CO2. The caproic acid, which was isolated by gas-liquid chromatography from periodate-permanganate oxidation of the labeled linoleic acid, was found to be inactive. The carbon 11 of the linoleic acid was isolated as BaCO3 after oxidation with KMnO4, in acetic acid and was found to be over 4.3 times as radioactive as the active azelaic acid carbons. It was concluded that the hen synthesized octadeca-9,12-dienoic acid from the 1-C14-cis-2-octenoic acid.