Occurrence of Fatty Acids with Uneven-numbered Carbon Atoms in Natural Fats

Abstract

ALTHOUGH the occurrence in natural fats of fatty acids containing odd-numbered carbon atoms, including n-heptadecanoic acid and n-pentadecanoic acid, has been claimed by various investigators, subsequent work has invariably revealed that such acids are actually equimolecular mixtures of adjacent members of even-numbered fatty acids. The generally accepted view at the present time is expressed by Hilditch1 as follows: “With the solitary exception of isovaleric acid (found only in the depot fats of the dolphin and porpoise) the molecules of all natural straight-chain fatty acids, saturated or unsaturated, contain an even number of carbon atoms”. Work in this laboratory, however, suggests that this view is not correct, and that fatty acids containing odd-numbered carbon atoms do, in fact, occur in some natural fats.