两种不同方法固定化β-葡萄糖苷酶的研究

Immobilization of β-Glucosidase by chitosan

以自制的壳聚糖微球为载体,戊二醛为交联剂,考察了壳聚糖浓度对微球制备的影响,并采用吸附-交联法和交联-吸附法两种方法对β-葡萄糖苷酶固定化进行了研究.结果表明:(1)当壳聚糖:2%乙酸溶液=1:20(w/w)时,最适合制球,成球粒径平均约为1.5mm.(2)采用交联-吸附法时固定率为43%,储存5天后剩余酶活力为67%,10天后剩余酶活力为52%,采用吸附-交联法时固定率为32%,储存5天后剩余酶活力为60%,10天后剩余酶活力为43%.因此,优化的固定化β-葡萄糖苷酶的方法为交联-吸附法.

β-Glucosidase is immobilized by using chitosan microspheres as carrier, cross-linked with glutaraldehyde. The influence of chitosan concentration on the chitosan microsphere preparation -is investigated, the methods of enzyme immobilization, i.e., adsorption - crosslinking and crosslinking- adsorption for β- glycosidase is studied. The results indicate that the ratio of chitosan： 2% acetic acid solution =1：20（w/w） is most suitable ratio for the preparation of chitosan microsphere, the average diameter of the chitosan microsphere is 1.5mm, and that the fixed rate of crosslinking-absorption is 43%, the residual enzyme activity is 67% after 5 days, while the residual enzyme activity is 52 % after l0 days. For absorption-cross-linking method, the fixed rate is 32%, the residual enzyme activity is 60% after 5 days, while the residual enzyme activity is 43 % after 10 days. So, crosslinking-adsorption is chosen as the best method to immobilize β-glycosidase enzymes.