论文部分内容阅读
采用乙醇分级沉淀、CMII纤维素离子交换柱色谱及凝胶柱色谱,从白豆中纯化得到一种α-淀粉酶抑制剂(α-AI),经SDS-PAGE及Sepharose CL-6B柱色谱鉴定其为结构均一的糖蛋白。该糖蛋白中蛋白质含量为88.2%,氨基酸组成主要为天冬氨酸、谷氨酸、苏氨酸及丝氨酸。糖链部分单糖组成为甘露糖、葡萄糖、半乳糖和木糖,其摩尔比为2.42∶1.50∶1.52∶1.00。糖和蛋白质结合的糖肽键类型为O-糖肽键。白豆α-AI使用剂量为150 mg.kg-1体重,连续使用7 d时,α-AI可明显降低高血糖大鼠的空腹血糖;使用剂量为300 mg.kg-1时,对高血糖大鼠的糖耐量具有明显的改善作用。研究结果表明,从白豆中分离得到的淀粉酶抑制剂对高血糖大鼠具有明显的降血糖功能,其作为一种安全、天然的降糖药物具有良好的开发前景。
An α-amylase inhibitor (α-AI) was purified from white beans by ethanol fractionation, CMII cellulose ion-exchange column chromatography and gel column chromatography and identified by SDS-PAGE and Sepharose CL-6B column chromatography. It is a structurally uniform glycoprotein. The protein content of this glycoprotein is 88.2%, and the amino acid composition is mainly aspartic acid, glutamic acid, threonine and serine. The monosaccharide composition in the sugar chain was mannose, glucose, galactose and xylose in a molar ratio of 2.42:1.50:1.52:1.00. The sugar and protein bound glycopeptide bond type is an O-glycopeptide bond. The dose of α-AI in white beans was 150 mg.kg-1 body weight. After continuous use for 7 d, α-AI significantly reduced the fasting blood glucose in hyperglycemic rats; when the dose was 300 mg.kg-1, it was hyperglycemia. The rat’s glucose tolerance has a significant improvement. The results showed that the amylase inhibitor isolated from white beans has a significant hypoglycemic effect on hyperglycemic rats, and it has good prospect as a safe and natural hypoglycemic drug.