Biokonversi minyak sawit kasar menggunakan desaturase
Abstract
Increasing unsaturation level of crude oil palm (CPO) could be carried out by using desaturase enzyme of Absidia corymbifera. This biocatalyst could also produce polyunsaturated fatty acids (PUFA) such as gamma linolenic acid that beneficial for healthy oil. The objective of this research was to determine the optimum contact time and ratio of immobilized desaturase enzyme-substrate in batch system at semi pilot scale (5,000-15,000 mL). Desaturase was extracted from A. corymbifera biomass and immobilized on activated zeolite (3-6 mm). Immobilized enzymes were then used for bioconversion process in batch system by mixing the enzyme with CPO in a bottle placed horizontally then rotated using a rotator machine at room temperature (25-30oC). The result showed that optimum contact time with ratio immobilized enzyme-substrate 1:1; 1:2; and 1:3 were 30, 40, and 50 min resulted in increasing iodine number 2.84; 3.94; and 4.46 g I2/100 g CPO, respectively. An optimum enzyme-subtrate ratio was achieved at 1:2, resulted in increasing of iodine number 9-11 g I2/100 g CPO, product recovery of 17,000 mL (21 batches) up to 18 hours. It was detected that active desaturases during CPO bioconversion were Δ6, Δ9, and Δ12 desaturases as shown by the increase of oleic (4.5%), linoleic (0,85%) and linolenic acids (60.7%).