Utilization of Immobilized Trypsin on Commercial Silica Gel as Catalyst

作者：Hodaifa G^*; Romero M D

来源：Chemical and Biochemical Engineering Quarterly, 2012, 26(1): 7-14.

• Transesterification
• trypsin
• enzyme immobilization
• silica-gel

In this study, trypsin was immobilized onto commercial silica gel and the transesterification of N-acetyl-L-tyrosine ethyl ester (ATEE) and 1-propanol in an organic solvent was used as a model reaction. The amount of trypsin adsorbed onto the support affected the time required to achieve full conversion. The concentration of immobilized trypsin that provided a maximum yield of product in a minimal amount of time was 43 mu mol of trypsin/g silica gel. At the end of transesterification reactions, the turnover frequency (9.3 . 10(-5) to 6.8 . 10(-3) s(-1)) and turnover number (8 to 520) of transesterification markedly increased when the initial concentration of the substrate had increased from 0.8 to 100 mmol L-1. The kinetic parameters K-m (64.8 mmol L-1 ATEE(initial)) and V-max (0.364 mmol L-1 ethanol min(-1)) were determined. The immobilized trypsin maintained enzymatic activity and reusability after one month of storage at 4 degrees C.

• 出版日期2012-3