茶中茶多酚的高效液相色谱法分离分析

Isolation and Analysis of GTPs by HPLC

用改进的Ａｇａｒｗａｌ方法萃取不同种类茶叶和茶饮料中的茶多酚（ｇｒｅｅｎｔｅａｐｏｌｙｐｈｅｎｏｌｓ，ＧＴＰｓ），建立了用高效液相色谱（ＨＰＬＣ）法对茶多酚进行分离分析的方法。ＨＰＬＣ可有效分离ＧＴＰｓ主要组成成分ＥＣ、ＥＧＣ、ＥＣＧ和ＥＧＣＧ并精确定量，相对标准偏差小于５％。茶叶加工过程对ＧＴＰｓ含量有很大影响，绿茶总ＧＴＰｓ含量在６～１５ｇ／１００ｇ干茶叶，乌龙茶总ＧＴＰｓ含量在５～７ｇ／１００ｇ干茶叶，红茶总ＧＴＰｓ含量低于２ｇ／１００ｇ干茶叶。

he method described by Agarwal et al.(1992) was modified and used to extract total green tea polyphenols (GTPs) from different tea and tea drinks. A method for the isolation and analysis of GTPs was developed using high performance liquid chromatography. The main components including epicatechin(EC),epigallocatechin(EGC),epicatechin gallate(ECG) and epigallocatechin gallate(EGCG) were well separated and quantified.The relative standard deviation (RSD) was less than 5%(n=3). It was found that the content of GTPs was significantly affected by the manufacturing process.The unfermented green tea contained about 615 g GTPs per 100 g dry tea leaves. In comparison,wulong tea contained about 5-7g GTPs while black tea had less than 2g GTPs per 100g dry tea leaves.