【作者】 张灵枝； 陈维信； 王登良； 谭新东； 郭剑英；

【Author】 ZHANG Lingzhi 1,CHEN Weixin2,WANG Dengliang 1,TAN Xindong 1,GUO Jianying 3(1.Tea Research Institute,South China Agricultural University,Guangzhou 510642,China;2.Guangdong Key Laboratory for Postharvest Science & Technology,College of Horticulture,South China Agricultural University,Guangzhou 510642,China;3.College of Veterinary Medicine,South China Agricultural University,Guangzhou 510642,China)

【机构】 华南农业大学茶业科学研究所； 广东省果蔬保鲜重点实验室华南农业大学园艺学院； 华南农业大学农业部兽药残留质量监督检验测试中心；

【摘要】 研究了不同渥堆程度普洱茶的体外抗氧化能力,研究结果表明:晒青毛茶和渥堆过程的普洱茶样对DPPH自由基、羟自由基均和超氧自由基均具有较强的清除能力和较强的总抗氧化能力,对DPPH自由基的清除能力各茶样均达到80%以上,对三种自由基的清除能力均以第一次翻堆样最强,其次是毛茶样品处理。对超氧自由基清除能力和总抗氧化能力而言,各处理之间差异显著,随着渥堆程度的加深,逐渐减弱,仍以第一次翻堆样最强,第四次翻堆样处理最低,低于毛茶处理。适当渥堆可以提高普洱茶水浸出物的体外抗氧化能力,过度渥堆则会引起其能力的下降,以至下降到毛茶的抗氧化能力之下。更多还原

【Abstract】 The antioxidant activities of water extracts of Pu-erh teas (WEOT)with different fermentation degrees were studied in vitro,compared to that of the sun-dried green tea water extract (control).Results showed as follows: All the extracts exhibited remarkable antioxidant abilities to scavenge DPPH,hydroxyl and superoxide anion free radicles,and DPPH being eliminated by as much as 80 %.The water extracts of the first-time pile-fermentation gave the strongest scavenging ability of the three free radicles followed by that of the sun-dried green tea .The superoxide anion free radicles scavenging activity and total antioxidation capacity of WEOTs had the most significant difference between the five tea samples(P<0.01).As the pile-fermentation duration lasted,the ability of water extracts of different samples gradually decreased and the first pile-fermentation WEOT exhibited the greatest activity,while the fourth pile-fermentation WEOT had the lowest activity which was lower than that of the sun-dried green tea water extract (control).The results indicate that proper pile-fermentation process could enhance the antioxidant activity of Pu-erh tea,but excessive pile-fermentation would provide the opposite effect.更多还原