不同品种茶叶指纹图谱的建立及其相似度评价

Establishment and Similarity Evaluation of Fingerprint of Different Varieties of Tea

目的:运用高效液相色谱(high performance liquid chromatography,HPLC)法建立不同品种茶叶的指纹图谱,为其质量控制和科学应用提供参考依据。方法:以10个茶叶品种33批样品为实验材料,采用75%甲醇水回流提取2次,并进行梯度洗脱(A相为0.2%磷酸水溶液,B相为乙腈),柱温30℃,流速1.0 mL/min,检测波长280 nm,采用指纹图谱相似度软件进行数据分析,并建立不同品种茶叶的指纹图谱共有模式。结果:10个品种茶叶的相似度在0.681~0.999,有5个共有峰,其中确认了没食子酸、表儿茶素没食子酸酯、表没食子儿茶素没食子酸酯3个共有峰。聚类分析结果将33批茶叶样品分为3类,即湄潭翠芽、凤岗锌硒茶、都匀毛尖、碧螺春、西湖龙井、天柱茶叶及绿宝石聚为一类,大红袍与铁观音茶聚为一类,遵义红茶聚为一类。结论:不同品种茶叶的品质差异显著,同品种不同等级、不同厂家的茶叶品质差异较小,此方法简便、准确、重复性好,可区分不同发酵工艺的茶叶,为茶叶的质量控制和科学应用提供参考依据。

Objective:The fingerprints of different varieties of tea were established by HPLC to provide a reference for the quality control and scientific application of tea.Methods:A total of 33 batches of 10 varieties of tea samples were used as experimental materials.75%methanol water was used for twice reflux extraction.The chromatographic conditions were as follows:Gradient elution was 0.2%phosphoric acid aqueous solution as mobile phase A and acetonitrile was as mobile phase B,column temperature was 30℃,flow rate was 1.0 mL/min,and detection wavelength was 280 nm.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 10 varieties of tea ranged from 0.681 to 0.999 with five common peaks,among which three common peaks of gallic acid,epicatechin gallate,epigallocatechin gallate were identified.33 batches of tea samples could be clustered into 3 groups by cluster analysis(Meitan Cuiya Tea,Fenggang Zinc Selenium Tea,Duyun Maojian Tea,Biluochun Tea,West Lake Longjing Tea,Tianzhu Tea and Emerald Tea were clustered in one category,Dahongpao Tea and Tieguanyin Tea were clustered in one category,Zunyi Black Tea was clustered in one category).Conclusion:There were significant differences in the quality of different varieties of tea,but the quality of the same variety,different grades and different manufacturers had little difference.The method is simple,accurate and reproducible,and it can distinguish tea with different manufacturing techniques to provide reference for tea quality control and scientific application.