利用(NH_4)_2SO_4分步盐析法从麦芽中初步分离极限糊精酶  

Research on preliminary purification of limit dextrinase from barley malt by ammonium sulfate precipitation

作　　者：付燕秋[1,2] 王欣宏[1] 管斌[1,2] 孔青[1] 余俊红 董建军 候松珍 

机构地区：[1]中国海洋大学食品科学与工程学院,山东青岛266003 [2]青岛啤酒股份有限公司,山东青岛266061

出　　处：《食品与发酵工业》2013年第1期199-202,共4页Food and Fermentation Industries

基　　金：山东省自然科学基金项目(ZR2010CM050)

摘　　要：文中对极限糊精酶的(NH4)2SO4盐析法进了研究。从大麦芽中萃取得到的粗酶液,采用(NH4)2SO4盐析法进行粗分级提取,绘制盐析曲线,确定盐析法纯化极限糊精酶的方案,并研究了各方案对极限糊精酶纯化纯度和得率的影响。研究结果表明:盐析曲线中饱和度分别为35%和80%时出现两个酶活峰,但80%饱和度时可以将绝大部分酶蛋白沉淀;分别采用一步法盐析(80%),二步法盐析(25%,80%),三步法盐析(25%,35%,80%)沉淀酶蛋白,其中三步法盐析可使极限糊精酶的纯度(A510/A280)达到1.635,纯化倍数和得率分别为8.8倍和49.5%,均优于其他两种方法。极限糊精酶盐析方案的优化可为其进一步分离纯化奠定基础。This paper mainly studied the method of ammonium sulfate precipitation,which could preliminary purify the limit dextrinase.Crude enzyme extracts from barley malt were purified by gradient ammonium sulfate salting,and the salting out curve was settled soon after.Accordingly,the preliminary purification method of ammonium sulfate salting was determined by salting out curve.In this paper,the influence of purity and yield of the limit dextrinase was studied for three methods of salting which were employed to purify limit dexrtinase.The results showed that it had two enzyme activity peaks in salting out curve at 35% and 80% saturation,but saturation of 80% could salt out most of the enzyme protein.We precipitated enzyme protein by one-step（80% saturation）,two-step（25% and 80% saturation） and three-step（25%,35% and 80% saturation） method,respectively.Wherein the three-step method could make the purity（A510/A280） of limit dextrinase up to 1.635,and the purification fold and yield was 8.8 and 49.5%,respectively.The results showed that the three-step（25%,35% and 80% saturation） salting was a better method to obtain high purity of limit dextrinase.This study is groundwork for further purification of limit dextrinase.

关 键 词：大麦芽 极限糊精酶 (NH4)2SO4盐析法 盐析曲线 

分 类 号：TS210.1[轻工技术与工程—粮食、油脂及植物蛋白工程]