ENZYMATIC ESTERIFICATION OF LONG POLYUNSATURATED FATTY-ACIDS AND LYSOPHOSPHATIDYLCHOLINE IN ISOOCTANE AND ETHANOL

Phosphatidylcholine (PC) was synthesized from lyso-PC and long polyuns aturated (n-3) fatty acids (PUFA) using immobilized phospholipase A2. The esterification was performed using the fatty acids as the main sol vent and isooctane or ethanol (99.5%) at low concentrations (7-45%) as additional solvents. The temperature was kept constant at 45-degrees- C and the water concentrations were carefully controlled. The best yie ld of PC (22%) was found in the isooctane system at a low water conten t (22% of the dry immobilized enzyme). In the ethanol system, the yiel d of PC was only half. The best yields were attained when the concentr ations of both isooctane and ethanol were below 7% and the reaction ti me was very long (9 days). Improved contact between the enzyme and the substrates would probably increase the reaction rate.