ENZYMATIC MODIFICATION OF MELON SEED OIL - INCORPORATION OF EICOSAPENTAENOIC ACID

Two immobilized lipases, IM60 from Mucor miehei and SP435 from Candida antarctica, were used as biocatalysts for the modification of the fatty acid composition of crude melon seed (Citrullus colocynthis L) oil by incorporating n-3 polyunsaturated fatty acid (PUFA). Higher eicosapentaenoic acid (EPA) incorporation was obtained by using EPA ethyl ester (97% pure) than by using EPA free acid (45% pure) for both enzyme-catalyzed reactions. IM60 required additional water to optimize the reaction condition, but any added water inhibited the catalytic activity of SP435. Increasing the molar ratio of acid or ester to triacylglycerol (TAG) significantly increased EPA incorporation, especially when EPA ethyl ester was used. The n-6 fatty acid content of melon seed oil was significantly lowered by using a high molar ratio of EPA ethyl ester to TAG. Incorporation of EPA into melon seed oil by immobilized lipase can increase the n-3 PUFA content, can help control the level of n-6 fatty acid, and may improve the nutritional quality of melon seed oil.