Preparation of n-3 PUFAs ethyl esters by an efficient biocatalyzed solvent-free process

alpha-Linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been subjected to esterification with ethanol in presence of lipase B from Candida antarctica (Novozym 435®), in solvent free condition. The use of alcohol donors triethyl orthoformate (TEOF) or diethyl carbonate (DEC) instead of free ethanol, allowed working in irreversible esterification conditions and ALA-, EPA- and DHA-ethyl esters were obtained in quantitative yields.