Institute of Applied Technology, Thu Dau Mot University, Thu Dau Mot City 820000, Binh Duong, Vietnam.
Proteomics and Metabolomics Core Facility, Center for Biotechnology, University of Nebraska, Lincoln, NE 68503, USA.
Molecules. 2021 Oct 27;26(21):6496. doi: 10.3390/molecules26216496.
Tea () and herbal tea have been recognized as rich sources of bioactive constituents with the ability to exert antioxidant actions. The aims of this study were to analyze phenolic, carotenoid and saccharide contents in a set of Vietnamese tea and herbal tea and compare the results with those of green and black teas marketed in the U.S. In total, 27 phenolics, six carotenoids and chlorophylls, and three saccharides were quantitatively identified. Catechins, quercetin glycosides and chlorogenic acid were the predominating phenolics in the teas, with the concentrations following the order: jasmine/green teas > oolong tea > black tea. Lutein was the dominant carotenoid in the teas and its concentrations were generally found to be higher in the jasmine and green teas than in the oolong and black teas. The study showed that the green teas originating in Vietnam had much higher levels of phenolics and carotenoids than their counterparts stemming from another country. The application of partial least squares discriminant analysis (PLS-DA) as a chemometric tool was able to differentiate phenolic profiles between methanolic extracts and tea infusions. Through principal component analysis (PCA), the similarities and dissimilarities among the jasmine, green, oolong, black teas and herbal teas were depicted.
茶和花草茶已被公认为富含生物活性成分的来源，具有抗氧化作用。本研究的目的是分析一组越南茶和花草茶中的酚类、类胡萝卜素和糖类含量，并将结果与美国市场上销售的绿茶和红茶进行比较。总共定量鉴定了 27 种酚类化合物、6 种类胡萝卜素和叶绿素以及 3 种糖类。儿茶素、槲皮苷和绿原酸是茶中的主要酚类化合物，其浓度顺序为：茉莉花/绿茶>乌龙茶>红茶。叶黄素是茶中的主要类胡萝卜素，其浓度通常在茉莉花茶和绿茶中高于乌龙茶和红茶。研究表明，越南产的绿茶中酚类和类胡萝卜素的含量比来自其他国家的绿茶要高得多。偏最小二乘判别分析（PLS-DA）作为一种化学计量学工具，能够区分甲醇提取物和茶浸出物之间的酚类图谱。通过主成分分析（PCA），描绘了茉莉花茶、绿茶、乌龙茶、红茶和花草茶之间的相似性和差异性。
