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通过DEAE-Sepharose离子交换层析和SephadexG-100凝胶过滤层析的联用从中华白玉蜗牛消化酶中分离出1种具有人参皂苷Rb1水解活性的β-葡萄糖苷酶。纯化后该酶在SDS-PAGE上呈单一蛋白质条带。反应最适pH为5.6,最适温度是80℃。pH稳定范围很广,在pH为4.0～11.0的溶液中和温度60℃以下保持长时间稳定状态,是一个耐碱和中等耐热的糖苷酶。Na+、K+、Li+、Ca2+、Mg2+、EDTA、DTT和SDS不影响该酶活性,而Cu2+、Ag+和Fe3+对该酶则具有明显的抑制作用。pNPG为底物的动力学参数Km和Vmax分别为0.182mmol/L和0.189μmol/(min.mg)。
A β-glucosidase with ginsenoside Rb1 hydrolytic activity was isolated from Chinese white jade snail digestive enzyme by DEAE-Sepharose ion-exchange chromatography and Sephadex G-100 gel filtration chromatography. The purified enzyme showed a single protein band on SDS-PAGE. The optimum reaction pH was 5.6, the optimum temperature was 80 ℃. It has a wide range of pH stability and is stable for a long period of time at a pH of 4.0 to 11.0 and at a temperature below 60 ° C. It is an alkali- and moderate-heat-resistant glycosidase. Na +, K +, Li +, Ca2 +, Mg2 +, EDTA, DTT and SDS did not affect the activity of the enzyme, but Cu2 +, Ag + and Fe3 + had obvious inhibitory effect on the enzyme. The kinetic parameters Km and Vmax of pNPG as substrates were 0.182mmol / L and 0.189μmol / (min.mg), respectively.