Structural characterization of a A-type linked trimeric anthocyanin derived pigment occurring in a young Port wine

• Type: Article in International Scientific Journal
• Date: 2013

Authors

Joana Oliveira (Author) FCUP; Mara Alhinho da Silva (Author) Other; Jorge Parola, AJ (Author) Other; Nuno Mateus (Author) FCUP; Natercia F Bras (Author) Other; Maria Joao Ramos (Author) FCUP; Victor de Freitas (Author) FCUP

Journal

Title: Food Chemistry

Vol. 141 No. 14

Pages: 1987-1996

ISSN: 0308-8146

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 32 Citations

Scopus - 40 Citations

Scientific classification

FOS: Agrarian Sciences > Other Agrarian Sciences

Other information

Authenticus ID: P-008-BFN

DOI: 10.1016/j.foodchem.2013.04.091

Abstract (EN): A new trimeric flavylium derivative pigment was detected for the first time in a young Port wine and structurally characterised using both API-LC ES! MS/MS and NMR techniques. Its structure comprises a malvidin-3-glucoside molecule (terminal unit) linked to two units of flavans (extension units) involving two A-type linkages (C4 -> C8 and C7-0-C2 ether linkages). The energies of the minimized geometries for all four conformations of this compound were calculated and comparing the structures of all isomers, it was verified that the binding mode (a or 13) between the first and second anthocyanin unit does not have a key role in the compound stability. However, for isomers I and 2 where the interaction between the second and third anthocyanin units occurs by a "beta" mode in opposition to the "alpha" mode verified in isomers 3 and 4, revealed a higher stability. The presence of these compounds in red wines is thought to result from their extraction from grape skin during fermentation, as the presence of these trimeric pigments was detected in a grape skin extract by API-LC ES! MS/MS spectrometry.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10