ENRICHMENT OF EICOSAPENTAENOIC ACID AND DOCOSAHEXAENOIC ACID-ESTERS FROM ESTERIFIED FISH OIL BY PROGRAMMED EXTRACTION ELUTION WITH SUPERCRITICAL CARBON-DIOXIDE

Methyl esters of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in esterified fish oil were extracted by supercritical fluid extraction with carbon dioxide and directly introduced into a silica gel column coated with silver nitrate. Supercritical fluid chromatography with carbon dioxide was then performed by changing stepwise the pressure of the column outlet. The EPA and DHA methyl esters thus separated were fractionated by reducing the pressure of column effluent to atmospheric. In this way, EPA and DHA methyl esters were enriched from 12% to 93% and from 13% to 82%, respectively. © 1990.