Standards-Based UPLC-Q-Exactive Orbitrap MS Systematically Identifies 36 Bioactive Compounds in Ampelopsis grossedentata (Vine Tea)

Abstract

Ampelopsis grossedentata (vine tea) has been used as a detoxifying beverage in China for centuries. To systematically identify its bioactive compounds, the study adopted standards-based ultra-high-performance liquid chromatography coupled with quadrupole/electrostatic field orbitrap high-resolution mass spectrometry (UPLC-Q-Exactive Orbitrap MS) analysis. The analysis was conducted under a negative ion model and the data were collected using the Xcalibur 4.1 software package. Based on comparisons with authentic standards, 36 bioactive compounds were putatively identified by four parameters: retention time, molecular ion peak, MS/MS profile, and characteristic fragments. These bioactive compounds include two chromones (noreugenin and 3,5,7-trihydroxychromone), 15 flavonoids (S-eriodictyol, S-naringenin, luteolin, ampelopsin, taxifolin, myricetin, quercetin, viscidulin I, kaempferol, myricetin 3-O-galactoside, myricitrin, avicularin, quercitrin, isorhamnetin-3-O-β-D-glucoside, and afzelin), four phenolic acids (gallic acid, 3,4-dihydroxy-5-methoxybenzoic acid, syringic acid, and ellagic acid), five tea polyphenols (epigallocatechin, epigallocatechin gallate, gallocatechin gallate, epicatechin gallate, and catechin gallate), three chalcones (phloridzin, phloretin, and naringenin chalcone), one stilbene (polydatin), two lipids (myristic acid and ethyl stearate), one sugar (D-gluconic acid), one amino acid (L-tryptophan), one triterpenoid (oleanolic acid) and one alkaloid (jervine). Notably, the jervine identification is the first report regarding the occurrence of alkaloid in the plant. Two chromones may be the parent skeleton to biosynthesize the flavonoid in A. grossedentata.