【摘要】 用壳聚糖作吸附剂、戊二醛作交联剂,对酵母蔗糖酶进行固定化研究,同时用琼脂糖固定化的蔗糖酶和游离酶与其进行比较。结果表明,壳聚糖固定化蔗糖酶贮藏稳定性、对变性剂以及对温度的耐受性均明显优越,而Km值与琼脂糖固定化酶相当,但比游离酶明显增高,酶的最适pH三者相近。研究表明,壳聚糖固定化酶所需的戊二醛浓度为0.6%,交联时间不低于6 h。固定化蔗糖酶对变性剂(乙醇、脲)的耐受力明显高于游离酶。更多还原

【Abstract】 Yeast sucrase immobilized to chitosan with glutaric dialdehyde as cross-linking agent was studied,while agrose-immobilized and free enzymes were as control.The results showed the stability of chitosan-immobilized enzyme increased much more than that of agarose-immobilized enzyme or free enzyme.The Michaelis-Menten Kinetics of chitosan-immobilized enzyme was equal to that of agarose-immobilized enzyme,but much higher than that of free enzyme.The optimum pH of these enzymes was almost the same.In preparation chitosan-immobilized enzyme,0.6% glutaric dialdehyde and more than 6 hr crosslinking were required.To free enzyme,chitosan-immobilized enzyme was more stable in ancohol or urea.更多还原