Identification of Anthocyanin-Flavanol Pigments in Red Wines by NMR and Mass Spectrometry

TLDR

Three new Port wine pigments were isolated by gel chromatography and semipreparative HPLC and identified using LC/MS and 1D/2D NMR. These pigments exhibit distinct UV‑visible spectra and are identified as malvidin 3‑glucoside linked via a vinyl bond to catechin, epicatechin, or procyanidin dimer B3, with their NMR spectra reported for the first time.

Abstract

Three newly formed Port wine pigments were isolated by Toyopearl HW-40(s) gel chromatography and semipreparative HPLC. Furthermore, the pigments were identified by mass spectrometry (LC/MS) and NMR techniques (1D and 2D). These anthocyanin-derived pigments showed UV-visible spectra different from those of the original grape anthocyanins. These pigments correspond to malvidin 3-glucoside linked through a vinyl bond to either (+)-catechin, (-)-epicatechin, or procyanidin dimer B3 [(+)-catechin-(+)-catechin]. NMR data of these pigments are reported for the first time.