不同茶类的高效液相色谱特征指纹图谱研究

目的高效液相色谱法(high performance liquid chromatography,HPLC)建立普洱茶等不同品种茶叶样品的指纹图谱。方法 28批茶叶样品经80%甲醇水溶液超声辅助提取,采用Waters C_(18)柱(4.6 mm×250 mm,5.0μm),以乙腈-0.5%乙酸为流动相进行梯度洗脱,流速0.7 mL/min,紫外检测器于270 nm波长进行目标化合物的检测。采用中药色谱指纹图谱相似度评价系统软件进行数据分析,并建立不同品种、不同厂家茶叶的指纹图谱集。结果不同品种茶叶的相似度在0.772-0.981之间,有18个共有峰,指认了其中儿茶素、表儿茶素、没食子儿茶素、表没食子儿茶素、没食子儿茶素没食子酸酯、表儿茶素没食子酸酯、表没食子儿茶素没食子酸酯7个共有峰。相似度结果结合聚类分析结果表明不同品种的茶叶能被准确识别分开,此方法实现了不同茶叶样品的准确分类和识别。结论不同品种、不同厂家茶叶的品质差异明显,高效液相指纹图谱结合化学计量学工具能够很好地提取茶叶的化学信息,并且能够准确地分类和识别不同品种茶叶,为茶叶的品种分类识别和质量控制提供参考依据。

Study on the characteristic fingerprints of different varieties tea by high performance liquid chromatography

Objective To establish the fingerprint of Pu''er tea and other tea samples by high performance liquid chromatography (HPLC). Methods A total of 28 batches of tea samples were used as experimental materials, after ultrasonic assisted extraction with 80% methanol solution, the tea samples were separated by Waters C18 column (4.6 mm ×250 mm, 5.0 m) for gradient elution using acetonitrile -0.5% acetic acid as the mobile phase with a flow rate of 0.7 mL/min. The target compound was detected by ultraviolet detector at 270 nm wavelength. The fingerprint similarity software was used for data analysis to establish a common fingerprint pattern of fingerprint of different varieties of tea. Results The similarities of different varieties of tea ranged from 0.772 to 0.981, with 18 common peaks, among which seven common peaks of catechin, epieatechin, gallocatechin, eepigallocatechin, gallocatechingallate, epicatechingallate, epigallocatechingallate were identified. Similarity results combining with cluster analysis results were different varieties of tea samples could be clustered into 2 groups, this method could realize the accurate classification and identification of different tea samples. Conclusion The quality of tea leaves from different varieties and different manufacturers is obviously different. High performance liquid chromatography fingerprint combined with chemometrics tools can extract chemical information of tea leaves well, and can accurately classify and identify different varieties of tea leaves, providing reference basis for variety classification, identification and quality control of tea leaves.