FIELD: chemistry.
SUBSTANCE: chromatographic separation method for producing a polyunsaturated fatty acid (PUFA) product from a feed mixture is provided. The method comprises: (a) purifying the feed mixture in the first chromatographic separation stage using a mixture of water and the first organic solvent as an eluent to produce an intermediate; and (b) purifying the intermediate in the second chromatographic separation stage using a mixture of water and the second organic solvent as an eluent to produce a PUFA product, wherein the second organic solvent is different from the first organic solvent and has a polarity index that is different from the polarity index of the first organic solvent in the range of 0.3 to 1.5, where the PUFA product is, at least, one ω-3-PUFA or, at least, one derivative of ω-3-PUFA, and wherein the PUFA product is not alpha-linolenic acid (ALA), mono-, di- or triglyceride of ALA or a complex C1-C4-alkyl ester of ALA or a mixture thereof.
EFFECT: increased purification efficiency of a PUFA product with a low level of C18 fatty acids.
26 cl, 16 dwg
