Hopeaphenol: the first resveratrol tetramer in wines from North Africa.
Grapes and wines are now known to constitute a rich source of phenolics such as stilbenes and flavonoids. These compounds have been shown to have cancer chemopreventive activity and potential beneficial effects on cardiovascular diseases thanks to their antioxidant and antiplatelet properties. However, because little is known about African wines and their phenolic compositions, we investigated wine samples from North Africa. A three-step method was used for the fractionation of the Merlot variety wine: column chromatography followed by centrifugal partition chromatography and reversed-phase semipreparative high-performance liquid chromatography (HPLC). Six polyphenolic compounds of the Merlot variety (from Algeria) were isolated and identified by NMR spectroscopy, five of which are known (trans-resveratrol, trans-piceid, trans-epsilon-viniferin, pallidol, and astilbin) and one that is reported for the first time in wine, (+)-hopeaphenol, a stilbene tetramer. Furthermore, these molecules were quantified in 10 commercial wines from North Africa by means of an analytical HPLC system coupled with diode array detection. Differences in concentrations were found ranging in mg/L from 4.6 to 45 (trans-piceid), 0.66 to 3.45 (trans-resveratrol), 0.2 to 1.2 (trans-epsilon-viniferin), 0.2 to 9.2 (pallidol), 0.3 to 3.8 (hopeaphenol), and 10.8 to 24.22 (astilbin). Such a high level of pallidol and astilbin has never been recorded in wine. North African wines may contribute to a significant proportion of dietary intake of stilbene and astilbin, which may have health benefits.
Guebailia
Habiba Amira
HA
Laboratoire de Chimie Appliquée, Université du 08 mai 1945, Guelma 24000, Algérie, France.
Chira
Kleopatra
K
Richard
Tristan
T
Mabrouk
Teguiche
T
Furiga
Aurélie
A
Vitrac
Xavier
X
Monti
Jean-Pierre
JP
Delaunay
Jean-Claude
JC
Mérillon
Jean-Michel
JM
D000352:Africa, Northern; D000462:Algeria; D002851:Chromatography, High Pressure Liquid; D005419:Flavonoids / Q000032:analysis / Q000302:isolation & purification; D044948:Flavonols / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy; D010636:Phenols / Q000032:analysis / Q000302:isolation & purification; D059808:Polyphenols; D000077185:Resveratrol; D013267:Stilbenes / Q000032:analysis*; D014920:Wine / Q000032:analysis*
D005419:Flavonoids; D044948:Flavonols; D010636:Phenols; D059808:Polyphenols; D013267:Stilbenes; C518233:hopeaphenol; C099069:astilbin; D000077185:Resveratrol