摘要
目的：从蟹壳中提取壳聚糖，将胰蛋白酶固定在从蟹壳中提取的壳聚糖上。方法：以自制壳聚糖为载体，戊二醛为双官能团交联剂，将胰蛋白酶固定化。结果：０．２ｇ壳聚糖（干）与４％戊二醛交联后再与５．０ｍｇ胰蛋白酶固定结合，效果较好。固定化酶的表现米氏常数Ｋ′ｍ＝１．５ｍｍｏｌ／Ｌ，而天然酶Ｋｍ＝７．６ｍｍｏｌ／Ｌ；固定化酶最适温度为８０℃，比天然酶提高了２０℃；固定化酶最适ｐＨ为７．０．而天然酶为８．０。该载体来源广，易提取，固定化酶的贮存稳定性很好，２个多月重复使用。
Objective:surney of trypsin was immobilized by chitosan.Objective:Using chitosan as a carrier,and glutaraldehyde as bifunctional cross linking reagent,the trypsin was immobilized.The method and conditions of trypsin immobilization as well as the characteristics of both immobilized and natural trypsins were studied.Results:(1)The optimum conditions for immobilization were 0.2g chitosan interconnected with 4%gltitaraldehyde,on which 5.0mg trypsin was then immobilized.(2)Apparent Michealis constant of immobilized trypsin K'm=1.5 mmol/L and that of natural trypsin K'm=7.6 mmol/L,(3)The optimum temperature of immobilized trypsin was 80℃,i.e,20℃ higher than natural trypsin(60℃).(4)The most suitable pH of immobilized trypsin was 7.0,and that of nattiral trypsin was 8.0.(5)The stability of immobilized trypsin was high after storage.
