检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
出 处:《中国农业大学学报》2017年第9期101-107,共7页Journal of China Agricultural University
基 金:中央高校基本科研业务费专项资金项目(2015ZCQ-LY-03);北京林业大学大学生创新创业训练项目(S201510022098)
摘 要:以湖南安化天尖、茯砖及广西六堡3种黑茶为考察对象,研究黑茶中茶多酚的提取工艺以及抗氧化性能。针对超声波不同提取条件,采用正交试验,确定黑茶中茶多酚的最佳提取工艺条件;采用清除二苯代苦味酰自由基(DPPH)的能力和邻苯三酚自氧化体系来评价其抗氧化活性。结果表明:采用超声波热水复合浸提法提取黑茶中茶多酚的最佳提取条件为超声波提取功率250 W,提取固液比1∶25,提取温度55℃,提取时间45min,茯砖黑茶中茶多酚的提取率5.21%;同时测得茯砖黑茶具有较好的抗氧化能力,对DPPH自由基有较强的清除能力,但与维生素C(VC)相比,其抗氧化能力比VC的能力弱;其清除超氧阴离子自由基能力的IC50为0.507μg/mL。To optimize the tea polyphenols extraction process,the method of ultrasonic-assisted water extracting was selected to discover the best conditions by an orthogonal experiment.In terms of the antioxidant performance appraisal,the scavenging rate of hydroxyl radical and superoxide anion radical were employed two indexes.The best ultrasonic-assisted water extracting conditions of tea polyphenols were as follows:Ultrasonic power 250 W;Tea-leaves mass to water volume ratio 1:25;Extracting temperature 55℃;Extracting time 45 minutes;and the best tea category,Fuzhuan tea.The extracting rate of Fuzhuan tea polyphenols reached 5.21%.Meanwhile,through the antioxidant performance test,Fuzhuan tea was estimated to be good in resisting oxidation,but its anti-oxidant activity was lower than that of VC.Itshowed excellent free radicals scavenging capacity to DPPH and its IC50 was 0.507 μ g/mL.
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.31