长裂苦苣菜甲醇提取物各极性成分的抗氧化活性研究

目的:为探明长裂苦苣菜不同溶剂提取物活性功能成分及体外抗氧化性。方法:利用石油醚、乙酸乙酯、正丁醇、水为溶剂依次萃取长裂苦苣菜全草甲醇提取物,测定不同溶剂萃取物的总酚、总黄酮及单体酚含量,采用DPPH法、ABTS法及总还原力法评价其抗氧化活性,分析其酚类物质含量与抗氧化活性间的相关性。结果:HPLC分析检测到长裂苦苣菜中至少含有9种单体酚成分,其含量在不同溶剂萃取物中存在显著差异。乙酸乙酯萃取物的总酚、总黄酮含量最高,分别达到170.74 mg GA Eq./g和6.01 mg RU Eq./g,且其抗氧化活性最强。不同溶剂萃取物的抗氧化能力与萃取物的黄酮含量之间极显著相关(p<0.01)。结论:长裂苦苣菜中含丰富的酚类、黄酮类抗氧化活性成分,乙酸乙酯可作为长裂苦苣菜抗氧化活性物质富集溶剂,富集长裂苦苣菜中的咖啡酸、芦丁、荭草素、木犀草素等抗氧化活性功能成分。 

Antioxidant activity of each polar composition from methanol extracts of Sonchus brachyotus DC.

Objective: In order to research the active components and antioxidant activities of different solvent extracts of Sonchus brachyotus. Result: different solvents such as petroleum ethyl,ethyl acetate,n- butanol and distilled water were used to extract S.brachyotus extracts obtained by methanol.The contents of total phenolics and flavonoids in different solvent extracts were analyzed and nine kinds of phenolics were detected by HPLC.Meanwhile,DPPH·,ABTS+· scavenging capacity and total reducing power were determined to compare antioxidant activity of different solvent extracts. The correlation between phenolics content of different solvent extracts and its antioxidant activities was analyzed.Result: There were nine kinds of phenolic components at least in Sonchus brachyotus detected by HPLC and the contents of them were different in different solvent extracts. Ethyl acetate extracts had the highest content of total phenolics( 170.74 mg GA Eq. / g) and flavonoids( 6.01 mg RU Eq. / g) and the strongest antioxidant activity. There was significant correlation between antioxidant activities of different solvent extracts and flavonoids content. Conculsion: The datum suggested that Sonchus brachyotus was rich in phenolics and flavonoids which had potent antioxidant activity. Ethyl acetate could be used as solvent-extraction to obtain the antioxidant in Sonchus brachyotus such as caffeic acid,rutin,orientin,luteolin et al.