Immobilization of Lipase on microporous and mesoporous materials: studies of the support surfaces

In this paper the performance of different supports respect to the lipase immobilization was investigated. The used enzyme was the lipase from Rhizomucor miehei (RML - commercial name: Palatase). The immobilization tests on mesoporous materials (MCM-41), de laminated zeolites (ITQ-2 and ITQ-6), Na-Silicalite-1, H-Silicalite-1 and F AU zeolites, were carried out by adsorption. The pore size, morphology, crystal dimension, acidity, hydrophobicity and chemical composition of the supports, strongly influence the amount of the enzyme adsorbed. The Na-silicalite-1 support shows the best lipase immobilization capacity, with an efficiency of c.a. 74% respect to the 41% of MCM-41 and the 27% of ITQ-2 type materials, while no enzyme is retained on the zeolite FAU (zeolite X). The preliminary activity tests using the lipase-support as a catalyst, were carried out for the reaction of hydrolysis of triglycerides. The activity observed for the lipase-Na-Silicalite-1 and the lipase-MCM-41 catalysts is 86% and 78%, respectively, respect to the activity of the free lipase enzyme in solution.