中文摘要：

目的：研究马齿苋全草提取物体外的抗氧化活性。方法：选取1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picryl-hydrazine,DPPH）自由基、羟基自由基、超氧阴离子自由基,以及还原能力体系对马齿苋提取物进行抗氧化活性测定。与阳性对照药没食子酸和维生素C作比较。结果：马齿苋提取物清除DPPH自由基、羟基自由基和超氧阴离子自由基的能力在低浓度时弱于阳性对照药没食子酸和维生素C,但随着浓度的增加,其清除活性均明显优于阳性对照药。在0~200μg/ml浓度范围内,马齿苋提取物的还原能力弱于2,6-二叔丁基对甲酚。结论：马齿苋提取物具有较好的清除自由基能力,但还原能力相对较弱。马齿苋可能是有效的外源性天然有机抗氧化剂。

英文摘要：

Objective：To investigate antioxidation activities in vitro of extract from Portulaca oleracea L..Methods：Antioxidation activity of the extract was determined by cleaning free radicals of 1,1-diphenyl-2-picrylhydrazine（DPPH）,hydroxyl,superoxide negative ion and reducing power assay.Results： The power of the extract at low concentrations for scavenging free radicals of DPPH,hydroxyl and superoxide negative ion were weaker than that of the positive control drugs gallic acid and vitamin C,but with the concentration increasing,the scavenging activities were better than those of gallic acid and vitamin C.The reducing power of the extract ranging from 0-200 μg/ml was weaker than that of butylated hydroxyltoluene（BHT）.Conclusion：The extract from Portulaca oleracea shows obvious scavenging free radical ability,while the reduction power is weaker than BHT.These results suggest that Portulaca oleracea would be an effective natural free radical scavenger.