91A-14 |
Trypsin immobilization on controlled pore glass beads |
D. LI, B. K. Simpson, and T. T. D. Nguyen. Food Science and Agricultural Chemistry, McGill University, 21,111 Lakeshore, Ste Anne de Bellevue, QC H9X 3V9, Canada Trypsin has many industrial applications, and it is a very important enzyme in the food industry. However, the cost of the enzyme is so high, in addition to its sensitivity to reaction conditions. Immobilizing the enzyme can make the trypsin stable and reusable. Among the various immobilization methods, covalent binding of enzymes to water-insoluble carriers seems to be the most attractive method for enzyme stabilization, recovery and reuse. Our objective was to optimize conditions for immobilization of trypsin from mammalian and fish sources. In this study, the covalent binding method was used to immobilize trypsin on controlled pore glass beads (CPG) with glutaraldehyde as activating reagent. The enzyme solution and CPG were incubated at 4C for 21 h. BAPNA was used as substrate to evaluate trypsin activity. The extent of immobilization and the conditions of immobilization were studied, and the catalytic properties as well as the stability of the immobilized trypsins were compared with those of the corresponding free enzymes. About 80% trypsin was immobilized on the CPG. The optimum pH stability of the immobilized enzymes (e.g., bovine trypsin) were shifted to relatively higher pH values (e.g., pH 11.0 for bovine trypsin) compared with the free form of the enzyme (pH 2.6). The immobilized enzymes retained more than 90% of their initial catalytic activity, even after being used 5 times. The results showed that trypsin can be immobilized on the CPG very well. Immobilization can make the enzyme reusable and stable, and it is expected that these features would facilitate commercial applications.
Session 91A, Food Chemistry: Enzymes, vitamins and plant pigments
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