粘毛蓼的抗氧化活性

用清除二苯代苦味酰基(DPPH)自由基、清除2,2′-连氨-(3-乙基苯并噻唑啉-6-磺酸)二氨盐](ABTS)自由基和铁离子还原/抗氧化能力(FRAP)测定法,对粘毛蓼体外总抗氧化活性进行了评价,结果与6-羟基-2,5,7,8-四甲基苯并二氢吡喃-2-羧酸(Trolox)及阳性对照丁基羟基茴香醚(BHA)、二丁基羟基甲苯(BHT)比较发现,粘毛蓼提取物有很好的体外抗氧化活性。乙酸乙酯提取物清除DPPH自由基(IC50=7.89 mg/L)的能力比BHT清除能力(IC50=18.71 mg/L)强,比BHA(IC50=3.20 mg/L)清除能力略弱;清除ABTS自由基能力(IC50=6.67 mg/L)比BHT(IC50=7.72 mg/L)清除能力强,比BHA(IC50=1.88 mg/L)清除能力弱;还原Fe3+的能力〔FRAP=(1362.55±47.22)μmol TE/g〕比BHT〔FRAP=(1581.68±97.41)μmol TE/g〕略低。在3种提取物中,乙酸乙酯提取物具有最高的抗氧化能力,甲醇提取物次之。3种方法中,DPPH方法和ABTS方法相关性最高(R=0.993)。

Antioxidant Activity of Extracts from Polygonum viscosum Buch.-Han. ex D. Don

The total antioxidant activity of the extracts from Polygonum viscosum Buch.-Han.ex D.Don was assayed by three methods,namely,1,1-diphenyl-2-picryl-2-picrylhydrazyl(DPPH) radical scavenging,(2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt(ABTS) radical scavenging,and ferric reducing antioxidant power(FRAP) assay.The results were compared with 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid(Trolox) and positive control butylated hydroxyanisole(BHA),2,6-di-tert-butyl-4-methylphenol(BHT).The results showed that P.viscosum Buch.-Han.ex D.Don had a good total antioxidant activity in vitro.The ethyl acetate extract from P.viscosum Buch.-Han.ex D.Don showed DPPH radical scavenging activity with IC50value of 7.89 mg/L higher than that of positive control BHT with IC50value of 18.71 mg/L,and slightly lower than that of BHA with IC50value of 3.20 mg/L.It showed ABTS radical scavenging activity with IC50value of 6.67 mg/L,higher than that of BHT with IC50value of 7.72 mg/L,and lower than that of BHA with IC50 value of 1.88 mg/L.It exhibited the ferric reducing antioxidant power with FRAP value of(1362.55±47.22) μmol TE/g,slightly lower than that of BHT with FRAP value of(1581.68±97.41) μmol TE/g.Among the three extracts of P.viscosum Buch.-Han.ex D.Don,the ethyl acetate extract showed the highest antioxidant activity,which was higher than the methanol extract.The results among the three methods were consistent,and the values obtained by ABTS assay were correlated the best with those obtained by DPPH assay(R=0.993).