黄花倒水莲不同极性部位抗氧化和降血糖活性研究

探究黄花倒水莲醇提物的不同萃取物的抗氧化和降血糖作用。采用95%乙醇制备黄花倒水莲提取物,通过有机溶剂萃取法对其进行纯化,分别得到石油醚部分、乙酸乙酯部分、正丁醇部分、氯仿部位和水相部分;采用Folin-Ciocalteu法分别测定其多酚含量,采用NaNO₂-Al(NO₃)₃法分别测定其黄酮含量;通过ABTS法、DPPH法、羟自由基法、α-葡萄糖苷酶抑制活性来评价黄花倒水莲的体外抗氧化、降血糖活性。结果显示,黄花倒水莲醇提物中多酚、黄酮含量丰富,经萃取分段后乙酸乙酯萃取物中多酚含量最高,可达(483.9±0.8)mg/g,石油醚部位黄酮含量最多高达(53.1±0.57)mg/g。黄花倒水莲醇提物及各萃取物均表现出很好的抗氧化能力。ABTS总抗氧能力显示乙酸乙酯部位抗氧化活性最强,其对羟自由基,DPPH自由基清除率远高于阳性对照V_C,此外其对α-葡萄糖苷酶具有较强的抑制活性(IC₅₀=(0.064±0.013)mg/mL),其作用强度远高于阳性对照阿卡波糖(IC₅₀=(0.867±0.032)mg/mL)。因此,黄花倒水莲各部位均有抗氧化,降血糖作用,乙酸乙酯部位最佳,可能活性成分为多酚类化合物。

Antioxidant and Hypoglycemic Activities of Different Parts Partitioned from the Ethanol Extract of Polygala fallax Hemsl

The antioxidant and hypoglycemic effects of different parts partitioned from Polygala fallax Hemsl ethanol extracts were investigated. Using 95% ethanol to extract P.fallax,organic solvent extraction method was exployed for purification,and petroleum ether part,acetate part,positive butanol part chloroform site and water phase were obtained respectively. By using Folin-Ciocalteu method,the total polyphenol content of extracts were determined.The content of flavonoids was determined by NaNO₂-Al(NO₃)₃ method. In addition,radicals scavenging(DPPH·,ABTS+ and ·OH),α-glucosidase inhibitory were carry out to evaluate their antioxidant and hypoglycemic activities. The results showed that polyphenols and flavonoids were abundant in the alcohol extract of P.fallax. After extraction,the content of polyphenols in ethyl acetate extract was the highest,reaching(483.9±0.8) mg/g,and the content of flavonoids in petroleum ether extract was the highest(53.1±0.57) mg/g and all the extracts from P.fallax possessed scavenging capacities for ABTS,DPPH and ·OH free radicals,the ethyl acetate fraction was in the highest degree,this fraction also showed an equally α-glucosidase inhibitory activity(IC₅₀=(0.064±0.013) mg/mL),and its effect strength was much higher than that of positive control acarbose(IC₅₀=(0.867±0.032) mg/mL). Therefore,all parts of the P.fallax have antioxidant and hypoglycemic effects,and the ethyl acetate part is the best. The active ingredient may be polyphenols.