半岛未凉°
食品技术
酶法脱除黄芪多糖中的蛋白质
闫巧娟 韩鲁佳 江正强 (中国农业大学 北京 100083)
摘要：探讨了5种蛋白酶对黄芪多糖中蛋白质的脱除效果，并与传统的Sevag法对比。结果表明：中性蛋白酶1的效果最好，用酶量为2U/mg处理多糖粗品，精制多糖得率为75.6%，脱去了89.1%的蛋白，多糖中蛋白质含量降低至0.72%。用Sevag法脱除黄芪多糖中的蛋白，反复进行15次萃取，最后多糖得率为62.8%，蛋白质含量为1.98%，脱去了69.9%的蛋白。而且，酶法具有经济、快速、高效安全、样品损失小等优点。因此应用酶法脱除黄芪多糖中的蛋白质明显优于Sevag法。
关键词：黄芪多糖；蛋白酶；蛋白质脱除；Sevag法
中图分类号：TS201.2 文献标识码：A 文章编号：1005-9989(2004)06-0023-04
Removal of protein from the crude astragalus
polysaccharides by proteases
YAN Qiao-juan HAN Lu-jia JIANG Zheng-qiang
(China Agricultural University, Beijing, 100083)
Abstract: The enzymatic removal of protein from the astragalus polysaccharides (APS) was studied. The effects of five industrial proteases to remove protein from APS were studied and compared to the traditional Sevag’s Method. Results showed that the best performance was observed with the neutral protease 1. By using 2U/mg of the protease for APS treatment, The refined APS sugar recovery was 75.6%, amount of protein removed was 89.1% and protein residual contents was 0.72%. In Sevag’s method, after extractions of 15 times, the final APS recovery was 62.8%, protein residual contents was 1.98% and amount of protein removed was 69.9%. Besides, the enzymatic method possesses other advantages such as economic, rapid, efficient, safe and minimum sample loss. Therefore, the application of enzymatic removal of protein from APS is obviously more superior to the Sevag’s method.
Key words: astragalus polysaccharides; protease; removal of protein; sevag’s method
0 前言
黄芪(Radix Astragali)是豆科植物蒙古黄芪Astragalus membranaceus (Fisch) Bge.Var.mongholicus (Bge) Hsiao.或膜荚黄芪A. membranaceus (Fisch) Bge.的干燥根。黄芪味甘，性微温，具有补气升阳、
收稿日期：2003-12-29
基金项目：国家“十五”攻关子课题“植物来源免疫增强剂研究与开发”(2002BA514A－12-3)。
作者简介：闫巧娟(1971-)，女，河北衡水人，博士研究生，副教授，主要从事生物质资源及天然生物活性物质的研究工作。
益卫固表、托疮生肌等功效，药用历史悠久，应用广泛，在我国产量很大，且畅销国内外。黄芪的活性成分主要为皂甙、黄酮、多糖等类化合物，其中黄芪多糖(APS)是黄芪中含量最高、也是特征的功效成分之一，具有促进免疫功能、双向调节血糖等作用[1]。
脱除其中的蛋白是多糖精制过程中比较重要的一步，传统方法有：Sevag法、三氯三氟乙烷法和三氯醋酸法。这几种方法脱除蛋白的效果虽然还可以，但都存在着许多缺点：有机溶剂用量大，耗时长，水
