Polyunsaturated Fatty Acids in Incubating Chicken Egg Lipids ,

In essential fatty acid metabolism the isomers of polyunsaturated fatty acids (PUFA) play a vital role. Since certain structural features at the methyl end (ω) of the fatty acid chain are keys to the biological activity of unsaturated fatty acids, an abbreviated nomenclature has come into use which identifies the methyl carbon as number one. In this system (Mohrhauer and Holman, 1963) linoleic acid is designated as 18:2ω6, linolenic acid as 18:3ω3, and arachidonic acid as 20:4ω6. The first number respresents the number of carbons in the chain, the second the number of double bonds and the number following the ω as the position of the first double bond from the methyl end of the fatty acid. Holman (1964) has reviewed the work of his group which has clearly established the conversion of linoleate to 20:4ω6 and 22:5ω6; linolenate to 20:Sω3, 22:5ω3, and 22:6ω3, as well as the nonconvertibility of…