Enrichment of EPA and DHA in glycerides by selective enzymatic ethanolysis

It has been reported that eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in glycerides have various biological functions. This study presents an effective method for enriching glycerides rich in EPA and DHA through lipase-catalyzed alcoholysis. The results showed that Eversa® Transform 2.0 had the strongest discrimination against DHA and EPA in alcoholysis, which was verified by molecular docking. Additionally, selectivity of the lipase and ratio of DHA and EPA in glyceride products were significantly affected by alcohol type. Under the optimal conditions, the contents of EPA and DHA in glycerides after ethanolysis reached 12.91 % and 55.40 %, respectively, with a DHA yield of 79.22 %. In this study, an interesting finding was that Eversa® Transform 2.0 could effectively differentiate EPA and DHA during alcoholysis to allow us to prepare DHA-enriched glycerides and EPA-enriched ethyl esters after removing saturated and monounsaturated ethyl esters.