The ginsenoside-glyosidase produced by Absidia sp. G8r was purified and characterized. The result indicated that its molecular weight is about 72 ku and the optimal temperature and pH for enzyme reaction were 30 and 5.0 respectively Enzyme is stable at 20-60 ℃, pH 3.0-7.0. Ions K+, Na+ , Ca2+ , Mg2+ , Zn2+ had no effect on the enzyme activity, while Cu2+ inhibited the enzyme activity. The enzyme hydrolyze Rb1 to C-K, in which Rb1 was hydrolyzed to Rd first in about 8 h, then Rd was hydrolyzed to F2 in about 18 h, and after that F2 was hydrolyzed to C-K. The Km of the enzyme are 5. 488, 5. 176, 5. 495 mmol/L, the Vmax of the enzyme are 1.524, 0. 904, 0. 447 mmol/(L · h).%对由Absidia sp.G8r菌产的人参皂苷糖苷酶(Glc8)进行了分离纯化,并对其酶性质和酶水解作用进行了研究.结果表明,该酶的分子质量约为72 ku,酶反应的最适温度和pH分别为30 ℃和5.0,在20～60 ℃、pH 3.0～7.0条件下稳定性较好.该酶水解人参皂苷Rb1生成人参皂苷C-K,水解过程是分步进行的,酶先水解Rb1生成Rd;大约8 h,酶水解Rd生成F2;大约18 h,酶水解F2生成C-K.并对此过程的酶反应动力学进行研究,米氏常数分别为5.488、5.176、5.495 mmol/L,最大反应速率分别1.524、0.904、0.447 mmol/(L·h).
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