石榴状凝胶微球固定化漆酶的制备、表征及降解双酚A

Preparation,Characterization and Degradation to BPA of Pomegranate-like Gel Microsphere Entrapmented Laccase

采用铜/锌复合金属磷酸盐晶体和海藻酸钙凝胶双重包覆技术对漆酶进行固定化,制得石榴状Alg@Cu_(3)/Zn_(3)(PO_(4))_(2)@Lac的凝胶微球.SEM,EDX和FTIR表征结果表明,在凝胶微球内部,漆酶被成功固定于由海藻酸钙凝胶包覆的铜/锌复合金属磷酸盐晶体内,铜/锌复合金属磷酸盐晶体镶嵌于海藻酸钙凝胶网格的孔隙中而呈石榴状.以2,2′-联氮双(3-乙基苯并噻唑啉-6-磺酸)(ABTS)为底物,经酶学性质研究表明,在无机盐晶体和海藻酸钙凝胶的双重保护下,Alg@Cu_(3)/Zn_(3)(PO_(4))_(2)@Lac的耐热性、耐酸性以及储存稳定性比游离漆酶均有不同程度增强.将Alg@Cu_(3)/Zn_(3)(PO_(4))_(2)@Lac应用于双酚A(BPA)的降解,采用孔径约1 mm滤网实现快速回收,经6次循环利用,对BPA的降解率下降约14%,显示出比较稳定的重复利用性和便捷的可操作性,这主要得益于海藻酸钙和铜/锌无机盐晶体对漆酶蛋白分子的双重保护.

The pomegranate-like gel microsphere Alg@Cu_(3)/Zn_(3)(PO_(4))_(2)@Lac was prepared by double embedding laccase in copper/zinc composite metal phosphate crystals and calcium alginate gel.Characterized by SEM,EDX and FTIR,the laccase was successfully embedded in copper/zinc composite metal phosphate crystals coated by calcium alginate.And the copper/zinc composite metal phosphate crystals were entrapped in the mesh pores of the calcium alginate gel like pomegranate-shaped.Enzymatic properties with ABTS as a substrate show that the heat resistance,acid resistance and storage stability of Alg@Cu_(3)/Zn_(3)(PO_(4))_(2)@Lac are enhanced under the double protection of inorganic salt crystals and calcium alginate gel compared to free laccase.Alg@Cu_(3)/Zn_(3)(PO_(4))_(2)@Lac was applied to the degradation of bisphenol A(BPA),and an aperture diameter of approximately 1 mm filter was used to achieve rapid recovery.The degradation rate of BPA decreased by only about 14%after six cycles,showing relatively stable reavailability,mainly due to the dual protection of calcium alginate and copper/zinc inorganic salt crystals.This paper provides the method and basis for establishing a new immobilization technology to enzyme.