Abstract:
The ultimate aim of this research project were divided into three parts. The first part concentrated on appropriate condition for fixing immobilized lipase from Candida cylindracea on ion-exchange resins. Immobilized enzyme catalysted reaction for the transesterification of racemic menthol with hexyl acetate was; therefore, used as a model reaction. The second part investigated the kinetic reaction parameters for immobilized enzyme. The effects of substrate flow rate to packed bed reactor and operation stability of immobilized enzyme were studied in the final part. The experiments were as a result, divided into three parts. The first part was to find appropriate conditions for enzyme immobilization. It was found that appropriate conditions time for immobilization were 5 hrs, concentration of lipase in buffer solution were 15 g/l and pH 7.0. The second part, the reaction mechanism was found to follow Ping Pong bi-bi type. The kinetic reaction parameters were Vmax = 83.33 mumol.hr-1 g-enz-1, kA = 85.58 mM, kB = 480 mM. when the reaction could be demonstrated as V = 83.33[A][B]/480[A]+85.58[B]+[A][B] In the final part it was found that the effective flow rate of substrate to packed bed was 70 ml/min. The operation stability of immobilized enzyme appeared to be very good., ie. loss of specific rate was only 24% after 10 days of operation, and the immobilized enzyme half life found was 25 days.