水蓑衣醇提物不同萃取部位的体外抗氧化活性研究

Study on Antioxidant Activity of Different Extraction Parts of Ethanol Extract from Hygrophila Salicifolia Herba in Vitro

目的研究水蓑衣醇提物不同萃取部位的体外抗氧化活性。方法采用有机溶剂萃取法将水蓑衣70%的乙醇粗提物分为石油醚、氯仿、乙酸乙酯、正丁醇和水部位,采用1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl radical,DPPH)自由基清除实验、2,2'-联氮双(3-乙基苯并噻唑啉-6-磺酸)二铵盐[2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate),ABTS]自由基清除实验与对铁还原能力(ferric ion reducing antioxidant power,FRAP)测定实验对水蓑衣的抗氧化活性进行评价,采用紫外可见分光光度法对各部位的总黄酮、总多酚和总多糖的含量进行测定,同时运用SPSS 20.0分析各部位的抗氧化活性与其化学成分的关系。结果水蓑衣不同萃取部位均具有一定的抗氧化活性,且在一定浓度范围内呈现量效关系。在DPPH自由基清除实验与ABTS自由基清除实验中,乙酸乙酯部位表现出更强的抗氧化能力,其次为正丁醇部位。对铁还原能力测定的实验中,正丁醇部位表现出更强的抗氧化能力,其次为乙酸乙酯部位。而含量测定结果显示,乙酸乙酯部位中总黄酮和总多酚的含量均最高,分别为42.22%、39.61%,其次为正丁醇部位,总黄酮和总多酚的含量分别为34.12%、33.39%。水部位的总多糖含量最高,为57.07%,其次是正丁醇部位,含量为39.42%。经过相关性分析结果显示,水蓑衣不同萃取部位的抗氧化活性与总黄酮和总多酚的含量关系密切,呈正相关,而与总多糖含量的相关性不明显。结论水蓑衣的乙酸乙酯部位与正丁醇部位具有较强的自由基清除能力,可能是其抗氧化活性的主要部位。而总黄酮和总多酚可能是其主要活性成分,可将其用于天然抗氧化活性成分的开发。

Objective To study the antioxidant activity of different extraction parts of ethanol extract from Hygrophila salicifolia herba in vitro.Methods The 70%ethanol crude extract from Hygrophila salicifolia herba was divided into petroleum ether,chloroform,ethyl acetate,n-butanol and water fractions by organic solvent extraction method.The antioxidant activity of Hygrophila salicifolia herba was evaluated by 1,1-diphenyl-2-trinitrophenylhydrazine(DPPH)radical scavenging assay,2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate)(ABTS)radical scavenging assay and iron reducing capacity(FRAP)assay.The contents of total flavonoids,total polyphenols and total polysaccharides in each part of Hygrophila salicifolia herba were determined by UV-visible spectrophotometry.Meanwhile,SPSS 20.0 was used to analyze the relationship between antioxidant activity and chemical composition of each part.Results The antioxidant activities of different extraction parts of Hygrophila salicifolia herba showed a dose-effect relationship in a certain concentration range.In DPPH free radical scavenging assay and ABTS free radical scavenging assay,the ethyl acetate extract showed stronger antioxidant capacity.Next is the n-butanol site.In the experiment of iron reduction capacity determination,n-butanol fraction showed stronger antioxidant capacity.The second part was ethyl acetate.The contents of total flavonoids and total polyphenols in ethyl acetate fraction were 42.22%and 39.61%,respectively.The contents of total flavonoids and total polyphenols were 34.12%and 33.39%,respectively.The total polysaccharide content in water part was the highest(57.07%).The content of n-butanol was 39.42%.Correlation analysis showed that the antioxidant activities of different extraction parts of Hygrophila salicifolia herba were positively correlated with the contents of total flavonoids and total polyphenols,but not with the contents of total polysaccharides.Conclusion The ethyl acetate and n-butanol fractions of Hygrophila salicifolia herba have strong free radical scavenging ability,which may be the main part of its antioxidant activity.Total flavonoids and total polyphenols may be the main active components,which can be used for the development of natural antioxidant active components.