Abstract
Lipase-catalyzed esterification is an efficient technique in the production of polyunsaturated fatty acid (PUFA) concentrates which are applied for nutrition and health purposes. In this project, a solvent-tolerant lipase from Streptomyces pratensis MV1 was immobilized and purified by a hydrophobic support. The purified lipase revealed enhanced activity and stability towards chemicals, organic solvents, and a broad range of pH values. The production of lipase was enhanced to 7.0 U/mL after optimization by a central composite design. Acylglycerols (AGs) rich in α-linolenic acid (45%, w/w) were produced and a favorable n-6/n-3 free fatty acid (FFA) ratio of 1.1 was achieved in fenugreek seed oil using the immobilized lipase. The ability of S. pratensis lipase in ester synthesis and the improvement of n6/n3 FFA ratio make it a suitable candidate in food production industries.