PVA小珠表面固定化α-淀粉酶及其性质研究

Immobilization of α-Amylase on PVA Bead and Its Properties

聚乙烯醇(PVA)具备优良的生物相容性和大量可以用于修饰的羟基。文中通过戊二醛交联得到水不溶性PVA小珠,对PVA小珠的表面进行环氧改性,并采用共价交联法固定化α-淀粉酶。对固定化与自由α-淀粉酶性质进行对比:固定化酶的最适催化温度(70℃)比自由酶(65℃)高,最适催化pH(6)与自由酶相同,热稳定性优于自由酶,对酸碱的敏感性也降低;重复使用8次仍保持60%酶活力。

The polyvinyl alcohol （PVA） is biocompatible and has lots of hydroxyls which can be modified. In this work, the PVA bead crosslinked with glutaraldehyde agent was modified with epichlorohydrin to immobilize the α-amylase by covalent binding. The properties of free and immobilized α-Amylase were also investigated and compared： the optimum catalyzed reaction pH （6） of immobilized α-Amylase was same as the free and the optimum catalyzed reaction temperature was 70℃, 5℃higher than the free; the results show that the stability of the immobilized α-amylase was improved; after eight times repeat operation, the relative activity of immobilized enzyme was about 60%.