Two Pairs of Isomerically New Phenylpropanoidated Epicatechin Gallates with Neuroprotective Effects on H2O2-Injured SH-SY5Y Cells from Zijuan Green Tea and Their Changes in Fresh Tea Leaves Collected from Different Months and Final Product

• DOI: 10.1021/acs.jafc.9b01365
• Publication Date: 2019-04-10T20:45:07Z
• Authors: Jia-Ping Ke; Wen-Ting Dai; Wen-Jun Zheng; Hao-Yue Wu; Fang Hua; Feng-Lin Hu; Gang-Xiu Chu; Guan-Hu Bao
• Keywords: SH-SY5Y

Zijuan tea ( Camellia sinensis var. assamica), an anthocyanin-rich cultivar with purple leaves, is a valuable material for manufacturing unique color and flavor. In this paper, four new phenylpropanoid substituted epicatechin gallates (pECGs), Zijuanins A-D (1-4), were isolated from green by different column chromatography. Their structures identified extensive high resolution mass spectroscopy (HR-MS), nuclear magnetic resonance (NMR), experimental calculated circular dichroism (CD) spectroscopic analyses. Detection of the changes in fresh leaves collected April to September final processed product performance liquid chromatography (HPLC)-HRMS suggested that production compounds 1 2 may be enhanced processing procedure tea. Additionally, 1-4 proposed synthesized through interaction between abundant secondary metabolite ECG phenolic acids two key steps phenol-dienone tautomerism. showed impressive activity protecting SH-SY5Y cells against H2O2-induced damage at concentration 1.0 μM.