壳聚糖固定化胰蛋白酶的研究

以壳聚糖为载体，戊二醛为交联剂，采用两种方法制备了固定化胰蛋白酶。考察了固定化反应中pH值，戊二醛的浓度，以及给酶量对固定化胰蛋白酶活力的影响，并研究了这两种固定化胰蛋白酶的性质。实验结果表明，以戊二醛预交联的网状壳聚糖为载体制备的固定化胰蛋白酶具有更加优良的性能，在最佳固定化反应条件下，酶的活性加收率可达56％。此固定化胰蛋白酶的最适pH为7．0－8．5，最适温度为60℃，Km值为2．52mol/L，固定化胰蛋白酶表现出较好的热稳定性，pH贮存稳定性，以及在乙醇水溶液中的稳定性。

STUDY ON CHITOSAN-IMMOBILIZED TRYPSIN

Two methods were employed to preparing immobilized trypsin using chitosan as the support and glutaraldehyde as the crosslinking agent. The activity of immobilized trypsin affected by pH value, glutaraldhyde concentration and amount of enzyme in the immobilized reaction was studied. The properties of immobilized trypsin were also studied. The results indicated that the immobilized trypsin from chitosan pre-crosslinking with a little glutaraldhyde had a prior character. Under the optimum immobilized reaction conditions, the activity retention value of this immobilized trypsin reached 56%. The optimum pH value of this immobilized trypsin was 7.0~8.5. The optimum temperature of this immobilized trypsin was 60C. The Km value of this immobilized trypsin was 2.52 mol/L. To compare with native trypsin, stability of immobilized trypsin to temperature, pH storage and ethyl alcohol was obviously improved.