Transesterification of phosphatidylcholine with eicosapentaenoic acid using phospholipase $A_2$ in organic solvent

Abstract

Phosphatidylcholine (PC) containing eicosapentaenoic acid (EPA C 20:5) in the sn - 2 position, was synthesized by phospholipase $A_2$ (porcine pancreatic phospholipase, $PLA_2$) mediated transesterification. The phospholipid modification was carried out in organic solvent media. The studied parameters were the effect of different solvents, time, water activity, acyl donor concentrations, the amount of $PLA_2$, and the pH of $PLA_2$. The modification was possible only when EPA ethyl ester (EPAEE) was used as an acyl donor in organic solvent system. The optimal conditions for the transesterification of the phosphatidylcholine were obtained by phosphatidylcholine and EPA ethyl ester (molar ratio of PC to EPAEE 1:10) in the presence of 10 mg (11 unit /mg) $PLA_2$ (pH 8.2) in 5 ml toluene at 50℃ for 48 h with the initial water activity ($a_w$) 0.25. The maximum incorporation of EPA into PC was 19.9% (w/w)