Linoleic acid

Linoleic acid (LA) is a polyunsaturated omega-6 fatty acid and is one of two essential fatty acids for humans, who must obtain it through their diet. It is a colorless or white oil that is virtually insoluble in water. Linoleic acid (LA) is a polyunsaturated omega-6 fatty acid and is one of two essential fatty acids for humans, who must obtain it through their diet. It is a colorless or white oil that is virtually insoluble in water. The word 'linoleic' derives from the Greek word linon (flax). Oleic means 'of, relating to, or derived from oil of olive' or 'of or relating to oleic acid' because saturating the omega-6 double bond produces oleic acid. Linoleic acid is a fatty acid. It is an 18-carbon chain with two double bonds in cis configuration. A shorthand notation like '18:2 (n-6)' or '18:2 cis-9,12' may be used in literature. It typically occurs in nature as a triglyceride ester; free fatty acids, the form not combined with glycerol to form triglyceride, are typically low in foods. It is very soluble in acetone, benzene, diethyl ether and ethanol. Linoleic acid is a polyunsaturated fatty acid used in the biosynthesis of arachidonic acid (AA) and thus some prostaglandins, leukotrienes (LTA, LTB, LTC), and thromboxane (TXA). It is found in the lipids of cell membranes. It is abundant in many nuts, fatty seeds (flax seeds, hemp seeds, poppy seeds, sesame seeds, etc.) and their derived vegetable oils; comprising over half (by weight) of poppy seed, safflower, sunflower, corn, and soybean oils. The consumption of linoleic acid is vital to proper health, as it is an essential fatty acid. In rats, a diet deficient in linoleate (the salt form of the acid) has been shown to cause mild skin scaling, hair loss,and poor wound healing. However, chronic consumption of high levels of LA may be associated with the development of ulcerative colitis. Cockroaches release oleic and linoleic acid upon death, which prevents other roaches from entering the area. This is similar to the mechanism found in ants and bees, which release oleic acid upon death. The first step in the metabolism of linoleic acid is performed by Δ6desaturase, which converts LA into gamma-Linolenic acid (GLA). There is evidence suggesting that infants lack Δ6desaturase of their own, and must acquire it through breast milk. Studies show that breast-milk fed babies have higher concentrations of GLA than formula-fed babies, while formula-fed babies have elevated concentrations of LA.