ÌìÃÀ´«Ã½

Abstract

Nanomaterials have been studied as enzyme support systems since they exhibit large surface area resulted in improved enzyme loading, which in turn showed increased apparent enzyme activity per unit mass or volume as compared to that of enzyme systems immobilized onto conventional materials. Thus, we explored the potential of nanomaterials for lipase immobilization. In present study, lipase from Candida rugosa was immobilized on CdS nanoparticles enriched with silane moieties. Characterization before and after modification were conducted using Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), Florescence Microscopy and Thermal Gravimetric Analysis (TGA). The effects of the reaction parameters such as pH, temperature, and molar ratio of the substrate to the solvent, acid to alcohol chain length on esterification are discussed. The results demonstrated that immobilized biocatalyst demonstrated 1.6 fold increased catalytic activity than crude lipase and recycled 15 times retaining 80% of its initial activity. Km and Vmax for immobilized lipase was found to be 0.38 mM and 205 �¼moles/mg/min; where as for free lipase Km was 1.4 mM and Vmax was 25 �¼moles/mg/min. Thus, the application of enzyme immobilized on functionalized CdS verifies to be promising system for ester synthesis in non-aqueous environment.

Biography

Email: vrutikaptl_19@yahoo.com