摘要
目的与方法:通过醇提得到各种茶多酚提取液,酒石酸亚铁法测定了多酚的含量;水提得到各种茶多糖提取液,用硫酸-苯酚法测定其中多糖的含量。通过DPPH·法、水杨酸法及邻苯三酚法测定不同茶叶中多酚、多糖含量对自由基的清除作用的影响,对比研究八种茶叶的抗氧化能力。结果:不同茶叶中多糖的含量从2.19%增大到2.89%(半发酵乌龙茶>红茶>绿茶),抗氧化能力:红茶>绿茶>乌龙茶(DPPH·法);红茶>绿茶>乌龙茶(水杨酸法);红茶>乌龙茶>绿茶(邻苯三酚法);不同茶叶中多酚的含量从1.71%增大到9.75%(绿茶>半发酵乌龙茶>红茶);结论:茶多糖和多酚是茶叶的主要抗氧化成分。绿茶的抗氧化作用主要来自茶多酚,红茶的抗氧化作用主要来自茶多糖。除乌龙茶多糖提取液外,两种抗氧化成分的抗氧化能力与其含量成量效关系。
Polysaccharides were extracted from different teas with hot water and their contents were determined by sulfuric acid-phenol method,while polyphenols were extracted with alcohol and their contents were determined by ferrous tartrate method.Then the scavenging effects of tea polysaccharide and polyphenol on free radicals were examined by DPPH.,salicylic acid and pyrogallol methods respectively,and the antioxidant capabilities of 8 kinds of tea were comparatively studied.Results showed that the polysaccharide...
出处
《食品科学》
EI
CAS
CSCD
北大核心
2009年第3期62-66,共5页
Food Science
基金
山西省自然科学基金项目(20051028)
教育部归国留学人员科研启动基金项目(2005383)
关键词
茶叶
多糖
多酚
自由基清除率
DPPH·法
水杨酸法
邻苯三酚法
tea
polysaccharide
polyphenol
free radical scavenging rate
DPPH.method
salicylic acid method
pyrogallol method
