广西小叶红叶藤不同极性溶剂提取物体外抗氧化活性

目的:研究小叶红叶藤Rourea microphylla不同溶剂提取物的抗氧化活性.方法:用冷浸法制备小叶红叶藤乙酸乙酯提取物(EAE)、丙酮提取物(AE)和乙醇提取物(EE),采用紫外分光光度法测定DPPH(1,1-二苯基-2-三硝基苯肼)自由基清除率2,2’-连氮基-双-(3-乙基苯并噻唑-6-磺酸)二铵盐(ABTS+)自由基清除率和铁离子还原能力,对小叶红叶藤3种提取物体外抗氧化活性进行考察.结果:小叶红叶藤乙醇提取物(EE)抗氧化能力最强,其ABTS+自由基及DPPH自由基半清除浓度(IC50)分别为0.66,0.60 g·L-1,还原能力强弱的顺序为EE＞ EAE＞ AE,与各提取物总黄酮含量一致.结论:小叶红叶藤提取物特别是乙醇提取物具有作为天然抗氧化剂和功能性食品进行研究和开发的潜力.

Antioxidant Activity of Different Extracts from Rourea microphylla in Guangxi

Objective: To study the antioxidant activity of different extracts from Rourea microphylla in Guangxi. Method: EE (95%ethanol), AE(acetone)and EAE (ethyl acetate) extracts were obtained by cold-extraction. The antioxidant activities were studied using DPPH(1,1-diphenyl-2-picrylhydrazyl radical 2,2-Dipheny l-1-(2,4,6-trinitrophenyl) hydrazyl)assay, 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS⁺) assay and reducing power assay by UV-VIS (Ultraviolet and visible spectrophotometry) spectrophotometry. Result: The EE of R. microphylla exhibited the most outstanding antioxidant activities. The IC₅₀ values of EE in DPPH assay and ABTS⁺ assay were 0.66,0.60 g·L^-1, respectively. The reducing power of all extracts was in the sequence of EE>EAE>AE, which was in accordance with the total flavonoid(TF)content. Conclusion: All the extracts especially EE extract of R. microphylla could be employed as natural antioxidants and health care products.