大豆β-淀粉酶、产气杆菌异淀粉酶在虾壳几丁质上的固定化及在麦芽糖生产中的应用

本文研究了大豆β—淀粉酶和产气杆菌异淀粉酶在同一载体上的固定化作用。以虾壳几丁质和壳聚糖为载体,证明几丁质更适于固定化异淀粉酶。用5％甲酸和50％乙酸预处理载体可增加固定化异淀粉酶的活性和稳定性,这可能是由于载体中壳聚糖的溶解造成的。经甲酸处理的几丁质先与4～6％pH7～9的戊二醛反应1小时,再同酶液(10mg/ml,pH6)反应2小时,并添加0.2mol/1Ca~#,将有利于固定化作用。用本方法得到的固定化酶具有高度活性和稳定性。固定化异淀粉酶最适pH由6.5变为5.0,而固定化β—淀粉酶最适pH变化不大。固定化酶在60℃稳定,在70℃5分钟失活。固定化酶在水中贮藏稳定,并具有良好的操作稳定性,使其在麦芽糖生产中具有潜在的应用价值。

Immobilization of Soybean β-amylase and A. aerogenes 10016 Isoamylase on the Shrimp Chitin and the Possible Applications in Maltose Industry

The immobilization of soybean β-amylase and A. aerogenes 10016 isoamylase on the same support was studied. Shrimp chitin and chitosan were used as the enzyme supports. It was proved that the chitin was more favorable since immobilized iosamylase obtained was active and stable. Pretreatment chitin with 5% formic acid or 50% acetic acid increased the specific activity and stability of the immobilized isoamylase, which might be responsible from the solubilization of chitosan from the supprots. After treatment with formic acid the shrimp chitin was first reacted with form-aldehyde(4-6%) at pH 7-9 for one hour, then reacted with enzymes (10mg/ml) at pH 6 for 2 hours, and the addition of Ca (0.2mol/L) would be favorable for the immobilization. The immbilized enzymes obtained with this method had high activity and stability. The optimum pH of the immobilized isoamylase was moved acidicly from 6. 5 to 5. 0, where as the immobilized β-amylase was not changed much. The immobilized enzymes were stable at 60℃ but deactivated at 70℃ for about 5 minutes. The immobilized enzymes was storage stable in water and operational stable for batch reaction, revealled its potential capcity of application in maltose industry.