脂环酸芽孢杆菌α-葡萄糖苷酶固定化及酶学性质研究

Enzymatic Properties of Immobilized α-Glucosidase from A. Contaminans

以戊二醛为交联剂,壳聚糖为载体,优化脂环酸芽孢杆菌α-葡萄糖苷酶的固定化条件,探讨固定化对酶性质的影响。结果表明:当戊二醛浓度0.2mol/L、戊二醛交联时间12h、交联pH7.5和交联温度15℃时,酶的固定化效果最佳。此时,固定化酶的最适pH4.5,最适反应温度55℃,在pH4.5～8.0范围酶的活性不受损失。当温度为65℃时,固定化酶的活力接近100%。酶储存3周以上,可以保持80%以上的活力。重复使用6次后,酶活保持在80%左右,说明固定化酶优化了游离酶的部分酶学性质,具有一定的应用价值。

α-glucosidase from Alicyclobacillus contaminans is immobilized with glutaraldehyde cross-linked chitosan. By the optimization of the immobilized conditions, the optimum conditions for the enzyme immobilization obtained are as follows： 0 the glutaraldehyde concentration was 0.2 tool/L, glutaraldehyde cross-linking time was 12h, cross-linking pH was 7.5 and cross-linking temperature was 15 ℃. Optimum pH and temperature for the immobilized α-glucosidase were 4.5 and 55 %, respectively. Enzyme activity would not be lost in the pH value between 8.0 and 4.5, when the temperature is 65 ℃, the immobilized enzyme can be kept close to 100% of enzyme activity and the enzyme activity could remain more than 80% when it was stored for three weeks, the enzyme residual activity remained at 80% when α-glucosi- dase was reused 6 times. So the immobilized enzyme has a certa in industrial applications.