Separation of natural polyunsaturated fatty acids by means of lodolactonization

Abstract

Conditions of the iodolactonization reaction (ILreaction) were optimized as a method for separation of natural polyunsaturated fatty acids. The effects of the solvent, temperature and the ratio of components of the iodizing complex KI/I 2 upon the rate of the synthesis of several iodolactones (ILs) in the IL‐reaction are described. It was shown that the rate of formation of γ‐ILs was significantly higher than that for δ‐ILs. This offers opportunity for obtaining pure docosahexaenoic acid (DHA) from fatty acid (FA) concentrates. The possibility for selective reduction of δ‐ILs in the presence of γ‐ILs to yield pure arachidonic acid (AA) or eicosapentaenoic acid (EPA) or fatty acid concentrates has been demonstrated. Preparation of pure AA from a mixture of AA, DHA and other FAs by the IL‐reaction without Chromatographie procedures is described.