7种广西产甜茶抗氧化活性的比较

通过清除二苯代苦味酰基(1,1-diphenyl-2-picrylhydrazyl,DPPH)法、铁离子还原测定(ferric reducing antioxidant power,FRAP)法、亚铁离子螯合(ferrous ion-chelating,FIC)法、β-胡萝卜素-亚油酸法等4种体外抗氧化活性测定方法,首次比较了3种茶科属茶叶和7种广西产甜茶水提物的抗氧化活性,同时用Folin-Ciocalteus法测定了其总多酚的含量。研究结果表明,多穗柯甜茶和藤茶的总多酚含量高于其他供试品。藤茶具有很好的清除DPPH·的能力,高于绿茶及阳性对照水溶性维生素E(Trolox)和人工合成抗氧化剂二丁基羟基甲苯(butylated hydroxytoluene,BHT)。甜叶菊茶和悬钩甜茶的金属离子螯合能力均高于绿茶。其中,黄杞和牛白藤两种植物的抗氧化活性为首次报道。由此可见,广西产甜茶均具有较高的开发利用价值,是治疗和防治慢性代谢性疾病的重要研究对象。对广西产甜茶的研究对于了解和抢救某些少数民族的历史文化具有重要意义,为别样茶的抗氧化研究奠定了基础,值得进一步探索和开发。

Antioxidants of seven types of sweet teas in Guangxi

To compare the primary antioxidant activities of seven sweet teas from Guangxi, we studied primary antioxidant activities of those tea based on four different reaction mechanisms,i.e.,1,1.diphenyl.2.picrylhydrazyl （ DPPH ） radical.scavenging activity, ferric.reducing antioxidant power （ FRAP ） , ferrous ion.chelating （ FIC） and β.carotene.linoleate bleaching assays. In addition, the total polyphenol content of each sample was estimated by Folin.Ciocalteus assay. Results show that the total polyphenol contents of Shilitiancha and Tengcha were higher than the other samples. The DPPH radical scavenging activity of Tengcha was superior to that of Green teas and positive controls Trolox and butylated hydroxytoluene （ BHT ） . The metal chelating capacity of Tianyejucha and Xungou tiancha was exceptionally stronger than that of green teas. Especially, the antioxidant activities of HuangQi and NiuBaiTeng were reported for the first time. The potential application of antioxidant sweet teas needs further to explored.