Analysis of Phytochemicals in WEAG

Reference standard phytochemicals, including quinic acid, 5-O-caffeoylquinic acid, caffeic acid, schaftoside, feruloylquinic acid, and quercetin-3-O-rutinoside, were purchased from Targetmol (Wellesley Hills, MA, USA), and quercetin-O-glucuronide, kaempferol-3-O-glucuronide, and isorhamnetin-3-O-glucuronide were obtained from ChemFace (Wuhan, China). WEAG were analyzed using a Dionex UltiMate 3000 system equipped with a Thermo Q-Exactive mass spectrometer, following previously published protocols with some modifications [17 (link),18 (link)]. Chromatographic separation was performed using a Dionex UltiMate 3000 system coupled with a C18 column (Acquity BEH, 100 × 2.1 mm, 1.7 μm) and a gradient system comprising 0.1% formic acid in water and acetonitrile. The Q-Exactive mass spectrometer operated in negative ion mode with a heated electrospray ionization source. The acquired data were subsequently analyzed using Xcalibur software (version 4.1, Thermo Fisher Scientific).