ABSTRACT
Polyunsaturated fatty acids (PUFA) of the n-6 and n-3 families are considered essential nutrients for humans and other animals. These essential fatty acids (EFA) are found in the body as unesterified free fatty acids or as components of cholesterol esters, triacyclglycerols, or esterified to the complex lipids of biological membranes. Following provision of the 18-C precursors, i.e., linoleic acid (LA, 18:2n-6) and αlinolenic acid (ALA, 18:3n-3) in the diet, animals have the biosynthetic capacity to convert these to longer-chain compounds through a series of desaturation and elongation reactions (reviewed in 1).
