Synthesis of phytosteryl ester containing pinolenic acid in a solvent-free system using immobilized Candida rugosa lipase.

Phytosteryl ester synthesized with pinolenic acid (PLA) from pine nut oil is expected to have features of both phytosterol and PLA. In this study, lipase from Candida rugosa (CRL) was immobilized and then used to optimize conditions for synthesis of phytosteryl ester containing PLA. Lewatit VP OC 1600, a macroporous hydrophobic resin, was selected as the best carrier, and the optimum condition for the immobilization of CRL was established. With immobilized CRL prepared, synthesis of phytosteryl ester with fatty acid from pine nut oil was carried out. Parameters investigated were temperature, molar ratio (phytosterol to fatty acid), enzyme loading, and vacuum. Optimum conditions for synthesis of phytosteryl ester were a temperature of 60 °C, molar ratio of 1:4, enzyme loading of 10% (based on the total weight of the substrate), and pressure of 80 kPa. The maximum conversion of phytosteryl ester was ca. 93 mol % at the optimum condition.