Identification and Geographical Traceability of 21 Flavono! Glycosides in Green Tea.

To distinguish the diflerences in the types and contents of flavonol glycoside in green tea from 6 production areas, and explore the feasibility of flavonol glycoside for geographical traceability of green tea. In this study, the qualitative identification of flavonol glycosides by ultrahigh performance liquid chromatography-quadrupole-electrostatic field or- bitrap high resolution mass spectrometry (UPLC-Q-Orbitrap HRMS), and a quantitative method of flavonol glycosides in green tea was established based on ultra high performance liquid chromatography -tandem triple quadrupole mass spec- trometry (UPLC-MS/MS). The results showed that a total of 21 kinds of flavonol glycosides were positively identified in green tea, including 5 myricetin glycosides, 8 quercetin glycosides and 8 kaempferol glycosides. The quantitative analysis showed that the content of flavonol glycosides varied from different producing area in green tea, in which the content of K-glu-rha-glu was the highest, accounting for 33.1% -57.8% of 21 kinds of flavonol glycosides, followed with the kaempferol glycoside, while content of myricetin glycoside was the lowest. By analyzing the differences and correlations of flavonol glycosides in green tea from 6 production areas indicate that they can be used for geographical traceability of tea. The green teas from different producing areas could be effectively distinguished by PCA. The precision rate was 100.0% for BP-ANN recognition, and 2 kinds of compound markers for flavonol glycoside were acquired with 100% importance (G<0.05). The predictive ability of PLS-DA model was 78.2%, and 8 biomarkers (VIP>1) were screened out. The entirety precision rate was 100% by LSD model, and the precision rate of cross validation result was 100%. The results of this study may provide scientific basis for the study of geographical traceability and chemical classification of tea. [ABSTRACT FROM AUTHOR]