安化黑茶水溶性成分高效液相色谱指纹图谱及定量分析

目的:运用高效液相色谱(high performance liquid chromatography,HPLC)法研究湖南安化黑茶指纹图谱,并对安化黑茶的主要成分进行定量分析,为湖南安化黑茶的成分分析与鉴别提供理论依据。方法:以22个安化黑茶样品与4种外省黑茶(云南普洱茶、湖北青砖茶、广西六堡茶、四川土司黑茶)为实验材料,采用梯度洗脱(A相为0.17%乙酸溶液,B相为乙腈),柱温30℃,检测波长280 nm,流速1.0 m L/min,建立安化黑茶HPLC指纹图谱,并进行了相似度评价与主成分分析,确定共有色谱峰。结果:22个安化黑茶样品具有19个共有色谱峰,这些黑茶样品在共有模式下的相似度为0.783~0.958,而广西六堡茶、四川土司黑茶、湖北青砖茶以及云南普洱茶与安化黑茶相似度很低(0.3);定量分析表明,安化黑茶中没食子酸、表没食子儿茶素没食子酸酯的含量明显高于4种外省黑茶,而广西六堡茶中的咖啡因和云南普洱茶中的没食子儿茶素含量明显高于安化黑茶;此外,茯砖素A仅在安化黑茶中检出,可作为安化黑茶的标志性成分。结论:根据所构建的安化黑茶HPLC指纹图谱及找到的标志性成分茯砖素A,可用于安化黑茶的鉴定与评价。

HPLC Fingerprint and Quantitative Analysis of Water-Soluble Components in Anhua Dark Tea

Objective: To fingerprint dark tea from Anhua, Hunan using high performance liquid chromatography (HPLC) and to quantitatively determine its major water-soluble constituents for the purpose of providing theoretical evidence for the identification of Anhua black tea. Methods: A total of 22 dark tea samples from Anhua, Hunan and 4 dark tea samples from other provinces (Liupu tea from Guangxi, Tusi tea from Sichuan, brick tea from Hubei and Pu’er tea from Yunnan) were fingerprinted by HPLC. The chromatographic conditions were as follows: gradient elution using 0.17% acetic acid aqueous solution as mobile phase A and acetonitrile as mobile phase B; column temperature, 30 ℃; flow rate, 1.0 mL/min; and detection wavelength, 280 nm. Similarity evaluation and principal component analysis were performed to ascertain the peaks common to these tea samples. Results: A total of 19 peaks were common to all Anhua dark tea samples with similarities ranging from 0.783 to 0.958 while the similarities between Anhua dark tea and other dark tea samples were quite low (lower than 0.3). Furthermore, the contents of gallic acid and epigallocatechin gallate in Anhua dark tea were remarkably higher than in any other dark tea, but caffeine in Liupu tea and gallocatechin in Pu’er Tea were significantly more abundant in Anhua dark tea. In addition, fuzhuanin A could be detected only in Anhua dark tea and hence regarded as an effective indicator for the identification of Anhua dark tea. Conclusion: The established HPLC fingerprinting method can be used to identify and evaluate Anhua dark tea based on fuzhuanin A content.