HPMC-PVA Film Immobilized Rhizopus oryzae Lipase as a Biocatalyst for Transesterification Reaction

The film prepared using a blend of hydroxypropyl methyl cellulose (HPMC) and polyvinyl alcohol (PVA) was investigated for immobilization of Rhizopus oryzae lipase. These immobilized lipase films were characterized using a combination of techniques like SEM, TGA, FT-IR, and Karl Fischer titration analysis. The biocatalyst was subjected to transesterification reaction of benzyl alcohol with vinyl acetate and was optimized for various reaction parameters such as effect of support, molar ratio, solvent, concentration of biocatalyst, time and temperature. Furthermore, the developed methodology was then effectively applied to various alcohols for synthesis of industrially important acetates providing good to excellent yields of desired products. Interestingly, the experimental results demonstrated catalytic activity of immobilized lipase to be 4-fold greater than that of free lipase for transesterification reaction. The immobilized biocatalyst was effectively recycled for four consecutive cycles and exhibited remarkable stability for a period 90 days.