共固定化乳糖酶和葡萄糖异构酶的研究

Study on the co-immobilization of β-galactosidase and glucose isomerase

研究了明胶-戊二醛法在共固定化乳糖酶和葡萄糖异构酶中的应用,并与开孔明胶法、卡拉胶包埋法进行了比较。进一步研究pH、明胶质量浓度、前交联中戊二醛的体积分数和二次交联的时间对明胶-戊二醛法共固定乳糖酶和葡萄糖异构酶的影响。结果表明,共固定化的最佳条件为:pH8.6,明胶浓度27%(w/w),前交联戊二醛体积分数0.15%和二次交联时间10min。在此条件下共固定化,乳糖酶的活力回收率为30.85%,葡萄糖异构酶的活力回收率为83.48%。共固定化乳糖酶和葡萄糖异构酶用于制备乳果糖,间歇操作6批次后酶活力仍然保持在初始活力的75%以上。

Adopting gelatin as carrier and using the method of embedding-crosslinking, β-galactosidase and glucose isomerase were co-immobilized in this study. Immobilization efficiency of this carrier was compared with that of open pore gelatin cube and K-carrageenan. The optimal co-immobilization condition was studied：pH was 8.6, gelatin concentration was 27% （ w/w）, glutaraldehyde concentration in the first cross-linking was 0.15% （v/v） and the time of second cross-linking was 10min. Under these conditions,the activity recoveries of β-galactosidase and glucose isomerase were respectively 30.85% and 83.48%. Furthermore, operating stability of the co- mmobilization enzyme system is also well.