【摘要】 利用Absidiasp.R菌株,通过液体发酵的方法,得到了一种高活性的大豆异黄酮糖基水解酶。该酶经硫酸铵分级沉淀、DEAE-Cellocuse(DE-52)离子交换层析纯化,被纯化了11倍,收率为10.9%;经SDS-聚丙烯酰胺凝胶电泳测得该酶的分子量为53kD;该酶的最适反应温度为50℃;最适pH为5.0;温度低于60℃,pH在5.0~7.0范围内该酶较稳定,Co2+、Ca2+对该酶有激活作用;Ag+、Cu2+对该酶有抑制作用。当以染料木甙为底物时该酶的米氏常数(Km)为1.3×10-2mol/L。等电聚焦电泳测得其等电点为3.2。更多还原

【Abstract】 A high activity isoflavone-glucosidase, which hydrolysis glycosides, was obtainde using liquid fermentation from Absidia sp.R strain. The isoflavone-glucosidase was purified 11 folds with yielding rate of 10.9% after ammonium sulfate precipitation and DEAE-Cellocuse(DE-52)ion exchange chromatography. SDS-PAGE results showed that the molecular weight is 53kD. And the optimum temperature, the optimum pH, K-m and pI of the enzyme are 50℃, 5.0, 1.3×10 -2 mol/L and 3.2, respectively. The isoflavone-glucosidase is also rather stable under 60℃ and in pH range from 5.0 to 7.0. The enzyme can be activated by Co 2+ and Ca 2+ , and be inhibited by Ag+ and Cu 2+ .更多还原