紫花芸豆胰蛋白酶抑制剂的分离和纯化

Isolation and Purification of Trypsin Inhibitor from Phaseolus vulgaris

[目的]从紫花芸豆中分离纯化胰蛋白酶抑制剂。[方法]以紫花芸豆为材料,采用脱脂、酸抽提、热变性、硫酸铵分级沉淀及离子交换层析和凝胶过滤层析等方法,分离纯化胰蛋白酶抑制剂。[结果]胰蛋白酶抑制剂经PAGE和IEF电泳显示单一条带。凝胶过滤法测定其表观分子量约为59 kD。SDS电泳结果显示它有3个亚基,分子量分别为341、61、5 kD。等电聚焦法测定其等电点为5.25。动力学的方法检测PVTI与胰蛋白酶发生不可逆抑制作用。[结论]离子交换层析和凝胶过滤层析法能快速地分离纯化紫花芸豆中的胰蛋白酶抑制剂。

[Objective] A trypsin inhibitor（PVTl）was isolated and purified from Phaseolus vtdgaris. [Method] PVTI was obtained by defating, extracting with dilute acid, heating, precipitating, ion exchange chromatography and gel filtration. [Result] PAGE and IEF of PVTI showed a single zone. The molecular weight of PVTI was 59 kD by gel filtration chromatography. The results of SDS-PAGE indicated that there were three subunits in protein molecular of PVTI. The molecular weight of those subunits was respectively 34, 16 and 15 kD. And the isoelectric point of the inhibitor was 5.25. PVTI belonged to irreversible inhibitor according to method of kinetic. [ Conclusion] PVTI was quickly obtained by ion exchange chromatography and gel filtration.