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采用甲苯自溶法从鲜酵母中提取了蔗糖酶，并用乙醇分级及ＤＥＡＥ－纤维素柱层析进行了纯化，用ＰＡＧ凝胶电泳作了纯度鉴定，在ｐＨ５．０，３０℃条件下进行了酶反应，用双倒数作图法测出其Ｋｍ＝２．１×１０－２ｍｏｌ／Ｌ，Ｖｍａｘ＝０．２６（每分钟的光密度值）．在此系统中，加入不同浓度的抗坏血酸（Ｖｉｔ．Ｃ），发现其具有激活作用并存在量效关系．双倒数作图显示：酶的表观Ｖｍａｘ（Ｖｐ）随抗坏血酸浓度的增加而增大，但其表观Ｋｍ（Ｋｐ）不变（Ｋｐ＝Ｋｍ）．经实验结果分析，推论出抗坏血酸激活作用的酶促反应方程式，并推导出反应速度公式
Sucrase was extracted from fresh yeast by toluene autolysis method and purified by ethanol fractionation and DEAE-cellulose column chromatography. The purity was determined by PAG gel electrophoresis. The purity was determined at pH 5.0 and 30 ℃ Enzyme reaction, measured by double reciprocal mapping Km = 2.1 × 10-2mol / L, Vmax = 0.26 (optical density value per minute). In this system, adding different concentrations of ascorbic acid (Vit.C), found that it has an activation and there is a dose-effect relationship. The double reciprocal plot shows that the apparent Vmax (Vp) of the enzyme increases with increasing ascorbic acid concentration, but its apparent Km (Kp) does not change (Kp = Km). Through the analysis of experimental results, deduced the enzymatic reaction equation of ascorbic acid activation and deduced the formula of reaction rate