以离子交换树脂固定化D-甘露糖异构酶及其性质研究

In this paper, D-mannose isomerase was immobilized on 10 types of macroporous adsorption resins and ion-exchange resins, in which FPA90 Cl performed the best immobilization effect. Using glutaraldehyde as a cross-linkage agent, the optimum conditions for the immobilization were as follows: enzyme load of 26 U/g resin, 4-hour absorption at 28℃, pH 8.5, adding the glutaraldehyde of which concentration was 0.04% and 2-hour cross-linking at 4℃. With these conditions, the recovery yield of the immobilized enzyme reached over 74%. The optimum temperature was 45℃, the optimum pH was 8.0, the temperature stability and pH stability were both better than the free enzyme. And it presented higher Michaelis constand than thefree enzyme and retained 80.8% of its initial enzyme activity after reuse for eight times, indicating that the immobilized enzyme has good operational stability.