食品科学 ›› 2007, Vol. 28 ›› Issue (12): 29-32.

• 基础研究 •    下一篇

白豆淀粉酶抑制剂的生物学性质及抑制动力学特征研究

 张晓琦, 杨明琰, 马瑜, 宋纪蓉   

  1. 陕西省微生物研究所; 西北大学化工学院 陕西西安710043; 陕西西安710043西北大学化工学院; 陕西西安710069; 陕西西安710043;
  • 出版日期:2007-12-15 发布日期:2011-11-22

Study on Biological Characteristics and Inhibition Kinetics of α-Amylase Inhibitor from White Kidney Beans

 ZHANG  Xiao-Qi, YANG  Ming-Yan, MA  Yu, SONG  Ji-Rong   

  1. 1.Shaanxi Microbiology Institute, Xi’an 710043, China; 2.College of Chemical Engineering, Northwest University, Xi’an 710069, China
  • Online:2007-12-15 Published:2011-11-22

摘要: 从白豆中提取纯化得到α-淀粉酶抑制剂糖蛋白(WBAI)。WBAI受温度及pH的影响较一般蛋白质稳定,在pH6.8孵育时间10min时,WBAI对猪胰α-淀粉酶的抑制作用最强(ID50=1.7×10-5mol/L),其抑制作用与抑制剂浓度关系密切,在抑制剂浓度较小的情况下抑制剂与酶的结合呈直线关系,随着抑制剂浓度的增大,抑制曲线出现漂移。Lineweaver-Burk图表明,WBAI淀粉酶抑制剂对淀粉酶的抑制类型呈非竞争性抑制,抑制常数Ki=9.4125×10-6mol/L。

关键词: 白豆淀粉酶抑制剂, 热稳定性, 抑制剂动力学, 抑制类型, 抑制常数

Abstract: Anα-amylase inhibitor (WBAI) glycoprotein was extracted and purified from white kidney beans. It had stronger stability to pH and temperature in comparison with other proteins. When incubated at pH6.8 for 10 min, it presented strongest inhibitory activity toα-amylase(ID50=1.7×10-5 mol/L).Its inhibitory activity is closely related to the concentration of the inhibitor. In the case of small inhibitor concentration, there would be a linear relationship for the combination of the inhibitor and amylase. The activity curve was drifted with increasing concentration of the inhibitor. Based on the studies of lineweaver-Burk plot, the WBAI presents an uncompetitive inhibition toα-amylase. The inhibitory constant(Ki) is 9.4125×10-6 mol/L.

Key words: white kidney bean &alpha, -amylase inhibitor(WBAI); stability; inhibition kinetics; inhibitory type; inhibitoryc onstant;