[Objectives]To explore the change rule of polyphenol content and antioxidant activity of coarse old leaves of Yingshan Yunwu Tea in the process of human digestion.[Methods]The coarse and old leaves of Yunwu tea in Yin...[Objectives]To explore the change rule of polyphenol content and antioxidant activity of coarse old leaves of Yingshan Yunwu Tea in the process of human digestion.[Methods]The coarse and old leaves of Yunwu tea in Yingshan,Huanggang,Hubei Province were selected as the research object,and their digestion in vitro was simulated.The total polyphenol content was determined by Folin-phenol reagent colorimetric method,and the DPPH radical scavenging activity and total antioxidant activity were determined.[Results]After simulated gastrointestinal digestion in vitro,the polyphenol content and antioxidant activity of coarse old leaf tea soup showed a downward trend.After gastrointestinal digestion,the polyphenol content in tea infusion separately decreased by 31.8%and 8.5%;the scavenging rate of DPPH free radical was 97%before digestion,decreased to 92%after gastric digestion and 65%after intestinal digestion,which decreased by 5%and 27%,respectively;after gastrointestinal digestion,the total antioxidant capacity of tea soup decreased by 4.7%and 3.1%,respectively.[Conclusions]This study provided a reference for the development and application of coarse old leaves of Yingshan Yunwu tea,and provided a reference for the nutritional value evaluation and comprehensive utilization of coarse old leaves,so as to make the best use of coarse tea leaves and reduce the waste of resources.展开更多
通过对当年新茶及其在室温条件下陈化处理1年后的陈茶进行HPLC分析,分别获得了其色谱峰,利用其峰面积数据(变量X)结合通过对新茶和陈茶分别人为定义的一个新数值(变量Y),用偏最小二乘法(partial least squares,PLS)建立了预测模型,通过...通过对当年新茶及其在室温条件下陈化处理1年后的陈茶进行HPLC分析,分别获得了其色谱峰,利用其峰面积数据(变量X)结合通过对新茶和陈茶分别人为定义的一个新数值(变量Y),用偏最小二乘法(partial least squares,PLS)建立了预测模型,通过量化的模型计算得到的预测值与新茶和陈茶的临界值的比较实现了新茶和陈茶的精确鉴别,对2006年生产的120个定标样和38个外部未知茶叶样品的鉴别准确率分别达到了100%和97.37%,同时对2007年生产的14个新茶样本的判别准确率也达到了92.8%。展开更多
基金Supported by High-level Training Project of Huanggang Normal University in 2021(202108504).
文摘[Objectives]To explore the change rule of polyphenol content and antioxidant activity of coarse old leaves of Yingshan Yunwu Tea in the process of human digestion.[Methods]The coarse and old leaves of Yunwu tea in Yingshan,Huanggang,Hubei Province were selected as the research object,and their digestion in vitro was simulated.The total polyphenol content was determined by Folin-phenol reagent colorimetric method,and the DPPH radical scavenging activity and total antioxidant activity were determined.[Results]After simulated gastrointestinal digestion in vitro,the polyphenol content and antioxidant activity of coarse old leaf tea soup showed a downward trend.After gastrointestinal digestion,the polyphenol content in tea infusion separately decreased by 31.8%and 8.5%;the scavenging rate of DPPH free radical was 97%before digestion,decreased to 92%after gastric digestion and 65%after intestinal digestion,which decreased by 5%and 27%,respectively;after gastrointestinal digestion,the total antioxidant capacity of tea soup decreased by 4.7%and 3.1%,respectively.[Conclusions]This study provided a reference for the development and application of coarse old leaves of Yingshan Yunwu tea,and provided a reference for the nutritional value evaluation and comprehensive utilization of coarse old leaves,so as to make the best use of coarse tea leaves and reduce the waste of resources.
文摘通过对当年新茶及其在室温条件下陈化处理1年后的陈茶进行HPLC分析,分别获得了其色谱峰,利用其峰面积数据(变量X)结合通过对新茶和陈茶分别人为定义的一个新数值(变量Y),用偏最小二乘法(partial least squares,PLS)建立了预测模型,通过量化的模型计算得到的预测值与新茶和陈茶的临界值的比较实现了新茶和陈茶的精确鉴别,对2006年生产的120个定标样和38个外部未知茶叶样品的鉴别准确率分别达到了100%和97.37%,同时对2007年生产的14个新茶样本的判别准确率也达到了92.8%。
