Utilization of bentonite as a support material for immobilization of Candida rugosa lipase

摘要

Bentonite is an inexpensive matrix for enzyme immobilization and has been frequently utilized for this purpose. In addition to its low cost, bentonite has several advantages for use as a support, including its lack of toxicity and chemical reactivity, allowing easy fixation of enzymes. In this article, Candida rugosa lipase was non-covalently immobilized on bentonite. The properties of immobilized enzyme were defined. Optimum pH and water content were determined as 7.5 and 100 μL, respectively. The patterns of heat stability indicated that the immobilization process tends to stabilize the enzyme. Half-lives of the immobilized enzyme at 50, 60, and 70℃ were 45, 15, and 4 min, respectively, whereas for the soluble free lipase it was 17 min at 50℃. Kinetics were tested at 37℃ following the hydrolysis of olive oil and obeys the Lineweaver-Burk type of rate equation. The K_m was 4 x 10~(-2) mM and the V_(max) was 15 mmol h~(-1) mg~(-1).