摘要：

The immobilization of papain on the mesoporous molecular sieve MCM-48 (with a pore size of 6.2 nm in diameter) with the aid of glutaraldehyde, and the characteristics of this immobilized papain are described. The optimum conditions for immobilization were as follows: 20 mg native free enzyme/g of the MCM-48 and 0.75 % glutaraldehyde, 2 h at 10–20 °C and pH 7.0. Under these optimum conditions for immobilization, the activity yield [%] of the immobilized enzyme was around 70 %. The influence of the pH on the activity of the immobilized enzyme was much lower compared to the free enzyme. The thermostability of the immobilized enzyme, whose half-life was more than 2500 min, was greatly improved and was found to be significantly higher than that of the free enzyme (about 80 min). The immobilized enzyme also showed good operational stability, and the activity of the immobilized enzyme continued to maintain 76.5 % of the initial activity even after

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