Palm oil hydrolysis by lipase from Candida cylindracea immobilized on zeolite type Y

Lipase from Candida cylindracea immobilized on hydrophobic zeolite type Y was used to hydrolyze palm oil in a microaqueous two-phase reaction system containing isooctane as organic medium and lecithin as surfactant. The lipase was immobilized to zeolite by adsorption. The maximum amount of bound protein at 8.2 mg g(-1) and an immobilization efficiency of 33% were achieved under optimum conditions. The kinetics of lipase binding to zeolite were assessed by using the general model of topochemical reaction. Based on the values of the specific kinetic model parameters, we propose that the adsorption process is controlled by surface kinetics that was later experimentally confirmed The activation energy for lipase adsorption on zeolite was 43 kJ mol(-1). The lipase immobilized an zeolite had 35% of the activity of the free enzyme. After the seventh cycle, immobilized lipase retained 10% of the initial activity in palm oil hydrolysis. (C) 1998 Elsevier Science Inc.