紫皮大蒜多酚分离纯化及体外降血糖活性研究

Isolation and Purification of Polyphenols from Purple-Skin Garlic and Their in Vitro Hypoglycemic Activity

研究以新鲜紫皮大蒜为原料,通过单因素试验和正交试验对紫皮大蒜多酚提取工艺进行研究。结果表明,紫皮大蒜多酚最佳提取工艺条件为乙醇体积分数60%、料液比1∶5、提取时间40 min、提取温度30℃,此时紫皮大蒜多酚提取量为2.92 mg/g。利用XDA-7大孔树脂纯化紫皮大蒜多酚,并研究其体外降血糖活性。纯化条件为紫皮大蒜多酚浓度2.5 mg/mL,吸附时间2 h;解吸时间1 h,乙醇溶液作为解吸液,解吸液浓度为60%,pH为5.0,纯化后的紫皮大蒜多酚含量为5.32 mg/g,提高了1.82倍。以阿卡波糖为阳性对照组,研究了紫皮大蒜对α-葡萄糖苷酶和α-淀粉酶的抑制作用。结果表明,紫皮大蒜多酚对α-淀粉酶和α-葡萄糖苷酶的半抑制浓度IC50值分别为5.076 mg/mL和5.501 mg/mL,紫皮大蒜多酚可以通过抑制α-葡萄糖苷酶和α-淀粉酶的活性从而达到降血糖的作用。

In this study,with fresh purple-skin garlic as the raw material,the extraction process of polyphenols from fresh purple-skin garlic is studied by single factor test and orthogonal test.The results show that the optimal extraction conditions of polyohenols from purple-skin garlic are ethanol volume fraction of 60%,solid-liquid ratio of 1∶5,extraction time of 40 min and extraction temperature of 30℃.At this time,the extraction amount of polyphenols from purple-skin garlic is 2.92 mg/g.XDA-7 macroporous resin is used to purify polyphenols from purple-skin garlic,and their in vitro hypoglycemic activity is studied.The purification conditions are purple-skin garlic polyphenol concentration of 2.5 mg/mL and adsorption time of 2 h;desorption time of 1 h,with ethanol solution as the desorption solution,the concentration of desorption solution of 60%,and the pH of 5.0,after purification,the purple-skin garlic polyphenol content is 5.32 mg/g,and the polyphenol content increases by 1.82 times.With acarbose as the positive control group,the inhibitory effects of purple-skin garlic onα-glucosidase andα-amylase are studied.The results show that the half inhibitory concentration IC 50 values of purple-skin garlic polyphenols onα-amylase andα-glucosidase are 5.076 mg/mL and 5.501 mg/mL respectively.Purple-skin garlic polyphenols could achieve the effect of lowering blood sugar by inhibiting the activities ofα-glucosidase andα-amylase.