Lipase immobilization on biodegradable film with sericin.

An ecofriendly and low-cost film composed by cassava starch, polyvinyl alcohol, and sericin blend (CS-PVA-SS) was synthesized, characterized, and applied as a novel support for Botryosphaeria ribis EC-01 lipase immobilization by enzyme-film-enzyme adsorption. Film revealed thickness between 230 and 309 μm and higher flexibility and malleability in comparison with film without SS. Based on p-nitrophenyl palmitate hydrolysis reaction, the activity retention of immobilized lipase was 987%. For optimal conditions, the yield in ethyl oleate was 95% for immobilized enzyme. Maximum yield was obtained at 49°C, molar ratio oleic acid:ethanol of 1:3, 1.25 g lipase film or 50 U (1.03 ± 0.03 mg protein) and 30 h. Even after seven cycles of use, immobilized lipase showed 52% reduction in ester yield. Biodegradable and biorenewable film is a promising material as a support to immobilize lipases and application in biocatalysis.