Application of Directly Coupled HPLC−NMR−MS to the Identification and Confirmation of Quercetin Glycosides and Phloretin Glycosides in Apple Peel

• Published in: Analytical chemistry (Washington) 2000-04, Vol.72 (8), p.1793-1797
• Main Authors: Lommen, A, Godejohann, M, Venema, D. P, Hollman, P. C. H, Spraul, M
• Format: Article
• Language: English
• Subjects: ANALYTICAL METHODS; APPLES; Biological and medical sciences; CHEMICAL COMPOSITION; CHEMICAL STRUCTURE; Chemistry; Chromatography, High Pressure Liquid; COMPOSE PHENOLIQUE; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; COMPUESTOS FENOLICOS; ESTRUCTURA QUIMICA; EXTRACCION; EXTRACTION; EXTRACTOS; EXTRACTOS VEGETALES; EXTRACTS; EXTRAIT; EXTRAIT D'ORIGINE VEGETALE; Food industries; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; GLICOSIDOS; GLYCOSIDE; GLYCOSIDES; Glycosides - analysis; HPLC; IDENTIFICACION; IDENTIFICATION; Magnetic Resonance Spectroscopy; MALUS PUMILA; MANZANA; Mass Spectrometry; PHENOLIC COMPOUNDS; Phloretin - analysis; PLANT COMPOSITION; PLANT EXTRACTS; POMME; QUERCETIN; Quercetin - analysis; QUERCETINA; QUERCETINE; RIKILT; Rosales - chemistry; RUTIN; RUTINA; RUTINE; Scientific imaging; Spectrophotometry, Ultraviolet; STRUCTURE CHIMIQUE; TECHNIQUE ANALYTIQUE; TECNICAS ANALITICAS; Wageningen Food Safety Research
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac9912303

Directly coupled HPLC−NMR−MS was used to identify and confirm the presence of quercetin O-glycosides and phloretin O-glycosides in an extract of apple peel. From the MS and MS/MS data, the molecular weights of the intact molecules as well as those of quercetin and phloretin and their sugar moieties were deduced. The NMR data provided information on the identity of the compounds as well as the α and β conformations and the position of the glycosides on quercetin and phloretin. The following O-glycosides of quercetin could be identified:  quercetin-3-α-l-rhamnosyl-(1 → 6)-β-d-glucoside (rutin), quercetin-3-β-d-galactoside (hyperin), quercetin-3-β-d-glucoside (isoquercitrin), quercetin-3-β-d-xyloside (reynoutrin), quercetin-3-α-l-arabinofuranoside (avicularin), and quercetin-3-α-l-rhamnoside (quercitrin). Phloretin was present as phloretin-2‘-β-d-glucoside (phloridzin) and the 2‘-β-d-xylosyl-(1 → 6)-β-d-glucoside. Concentrations were between 0.2 and 5 mg/g of apple peel.