中文摘要：

目的建立茶叶中3种儿茶素检测方法,比较目前市场不同品种茶叶中儿茶素含量差异性。方法采用改进的高效液相色谱（HPLC）法测定了不同茶叶中3种儿茶素的含量,对5个不同品种茶叶进行了儿茶素含量差异性检查。色谱柱为Hypersil BDS C18（250 mm×4.6 mm5,μm）柱;流动相为乙腈∶0.1%柠檬酸溶液=10∶90;柱温30℃,波长280 nm。结果改进的HPLC方法测定3种儿茶素在2～400 mg.L-1范围内线性关系良好（r〉0.999）,平均回收率〉99.0%,精密度〈2.0%。结论不同品种茶叶中儿茶素含量变化差异性较显著。建议进一步研究和完善茶叶的采摘、加工及贮存等流程,并制定出科学、合理的质量标准。

英文摘要：

Objective To establish a method for determination of three kinds catechin in tea and compare content of which from different species of tea in current market. Methods The content of three kinds of catechin was measured by modified HPLC method and difference of which was tested.The determination was performed on Hypersil BDS C18（250 mm×4.6 mm,5 μm）column with acetonitrile-0.1% citric acid（10：90）as mobile phase at detection wavelength of 280 nm.And the column temperature was set at 30 ℃ and the wave length was 280 nm. Results The good linear relationship of three kinds of catechin occurred in the range of 2-400 mg·L-1（r0.999）.And the average recoveries were more than 99.0% and RSD were less than 2.0%. Conclusion There was great difference in the content of catechin from five species of tea.It is suggested to further study and complete picking,processing and preserving of tea and formulate scientific and resonable quality standard.