酵母蔗糖酶的提取方法  

Study on Purification of Invertase from Yeast

作　　者：李楠[1] 庄苏星[1] 丁益[1] 

机构地区：[1]南京大学生命科学学院,医药生物技术国家重点实验室,江苏南京210093

出　　处：《食品与生物技术学报》2007年第4期83-87,共5页Journal of Food Science and Biotechnology

摘　　要：采用甲苯自溶法、冻融法、SDS抽提法3种方法从酵母中提取蔗糖酶,经质量分数50%的乙醇分级沉淀、Mono Q阴离子交换柱层析纯化后,制得高纯度的酵母蔗糖酶。比较了上述3种提取方法并对该酶的部分性质进行了研究。纯化的酶经等电聚焦测定,等电点为5.6,SDS-PAGE鉴定其相对分子质量为60kD。以蔗糖为底物测得酵母蔗糖酶的表观米氏常数Km为0.013mol/L。结果显示3种提取方法各有优劣,冻融法和SDS抽提法的提取效率远高于传统的甲苯自溶法。其中SDS抽提法的效率最高,加之其操作简便,更适合于酵母蔗糖酶大规模的制备提取。This paper used three methods to extract invertase from yeast, which included in this manuscript, three different extraction method breaking cells by adding methylbenzene, frost grinding, and adding SDS for extracting invertase from yeast were investigated. Then the purified invertase was obtained by precipitatation with 50% ethyl alcohol and Mono Q chromatography. The molecular weight of the enzyme was 60kD by SDS-PAGE, and the pI was 5. 6 by isoelectric focusing. The invertase followed typical Michaelis-Menten Kinetics with apparent Krn of 0. 013 mol/L. The results showed all three methods had both advantages and disadvantages. The invertase extracted by adding SDS and frost grinding had much more total activity than that of extracted by adding methylbenzene. A highest total invertase activity was found in the SDS extraction process, and it was a convenient and economical method for commerical production of invertase from yeast.

关 键 词：酵母 蔗糖酶 提取 纯化 

分 类 号：Q814.1[生物学—生物工程]