Production of phytosteryl ester from echium oil in a recirculating packed bed reactor using an immobilized lipase

The synthesis of phytosteryl ester via the lipase-catalyzed esterification of phytosterol with fatty acid from echium oil was performed in a recirculating packed bed reactor. A commercial lipase from Candida rugosa was immobilized and then used to optimize the reaction conditions for the synthesis of the phytosteryl ester. The parameters investigated were temperature, molar ratio of phytosterol to fatty acid, retention time, and amount of solvent. The optimum conditions were determined as the temperature of 40°C, the molar ratio of 1:3 (phytosterol to fatty acid), the retention time of 3 min, and the solvent amount of 40 mL. The maximum conversion of phytosteryl ester was ca. 90 mol% under the optimum conditions. The major fatty acid in phytosteryl ester synthesized was α-linolenic acid (ca. 38 mol%).