黄大茶茶汤成分分析及抗氧化活性研究

实验检测黄大茶茶汤、茶多糖类组分、茶多酚类组分儿茶素的含量，并通过自由基清除实验，以及对高脂日粮诱导肥胖小鼠肝脏和肠道氧化还原状态的调节，研究黄大茶各组分的抗氧化活性。结果表明，茶汤和茶多酚类组分儿茶素含量均高于茶多糖类组分。相同浓度下，茶多酚类组分清除DPPH自由基、羟自由基和超氧阴离子自由基能力最强，茶多糖类组分最弱。动物实验研究表明，茶汤、茶多糖类组分和茶多酚类组分均可显著（P<0.05）提高高脂诱导肥胖小鼠回肠总抗氧化能力（T-AOC）；茶汤和茶多酚类组分显著（P<0.05）降低回肠丙二醛（MDA）含量。茶多糖类组分显著（P<0.05）降低高脂日粮小鼠肝脏 MDA的含量。3种物质均可提高高脂日粮小鼠回肠和肝脏 GSH-Px活力，但差异不显著。结论表明，黄大茶茶汤、茶多糖类组分和茶多酚类组分均具有抗氧化活性。

Study on the composition and antioxidant activity of Large Yellow Tea water extract

In this study, we obtained water extract from Large Yellow Tea, then using high performance liquid chromatography (HPLC) to test the catechins content in water extract (WE), crude tea polyphenol (RTPP) and crude tea polysaccharides (RTPS), and in vitro free radical scavenging activity and in vivo liver and gut redox status of high fat diet (HFD) induced obese mice were further examined. The results showed that the catechins contents in WE and RTPP were higher than TRPS. In vitro free radical scavenging of WE, RTPP and RTPS showed that RTPP had the highest DPPH( scavenging, hydroxyl free radical and superoxide anion free radical activity, while RTPS had the lowest free radical scavenging activity. Animal study showed that WE, RTPP and RTPS significantly (P<0.05) improved T-AOC capacity of ileum; WE and RTPP significantly (P<0.05) decreased the ileum MDA level; RTPP significantly (P<0.05) decreased liver MDA level. The GSH-Px activity was improved in ileum and liver by WE, RTPP and RTPS, but not significant. In conclusion, WE, RTPP and RTPS have antioxidant activity in vitro and in vivo.