不同极性溶剂的草果提取物抗氧化活性研究

Studies on antioxidant activity of Amomum tsao-ko extracts with different polar solvents

目的研究不同极性溶剂草果提取物的抗氧化活性。方法用95%乙醇提取草果,过滤并将滤液浓缩成浸膏,用少量蒸馏水溶解浸膏后依次用石油醚、乙酸乙酯、正丁醇萃取,得到石油醚部位、乙酸乙酯部位、正丁醇部位以及水部位。采用紫外分光光度法来测定草果提取物对ABTS+自由基、羟自由基和Fe^(2+)螯合的清除能力,比较其抗氧化活性,并用BHT作为阳性对照品。结果不同极性溶剂的草果提取物对ABTS+自由基、羟自由基和Fe^(2+)螯合都具有清除能力,清除ABTS^(+)自由基的能力以阳性对照品最强,高达90.56%,清除羟自由基能力大小为:正丁醇部位>BHT>石油醚部位>乙酸乙酯部位>水部位,清除螯合Fe^(2+)能力中,当提取物浓度为4.0μg/ml时,正丁醇部位螯合清除能力最强,石油醚部位螯合清除能力最弱。其中又以BHT的Fe^(2+)螯合能力、ABTS^(+)自由基清除能力、羟自由基清除能力最好。结论不同极性溶剂的草果提取物都具有良好的抗氧化活性,其中以BHT作为阳性对照品对草果的抗氧化活性最好,其次是正丁醇部位、石油醚部位、乙酸乙酯部位,最后是水部位。

Objective To study the antioxidant activity of Amomum tsao-ko extracts with different polar solvents.Methods The Amomum tsao-ko was extracted with 95% ethanol,and then filtrated and concentrated into the extractum.The extractum was dissolved in a small amount of distilled water,and then extracted with the petroleum ether,ethyl acetate,n-butanol and ethyl acetate to get respective extract liquor and water part,respectively.Uv spectrophotometry was used to determine the scavenging ability of Amomum tsao-ko extracts against ABTS^(+) free radical,hydroxyl free radical and Fe^(2+) chelation,and antioxidant activity was compared.BHT was used as the positive control.Results The extracts of Amomum tsao-ko with different polar solvents had scavenging ability on ABTS+free radical,hydroxyl free radical and Fe 2+chelation.The positive control had the strongest scavenging ability on ABTS+free radical,being as high as 90%.The scavenging ability on hydroxyl radical was as follows:the n-butanol part>BHT>petroleum ether part>ethyl acetate part>water part.When the concentration of extract was 4.0μg/mL,the n-butanol part had the strongest scavenging capacity on Fe^(2+) chelation,while the petroleum ether part was the weakest.Among them,BHT had the best scavenging ability on Fe^(2+) chelation,ABTS^(+) free radical and hydroxyl free radical.Conclusion Amomum tsao-ko extracts with different polar solvents have good antioxidant activity.Among them,BHT as the positive control had the best antioxidant activity,followed by n-butanol part,petroleum ether part,ethyl acetate part,and finally water part.