MORE ARTICLE
PREVIEWS | 05/04/2007
So how do you prefer your red wine?
With cis-resveratrol or trans-resveratrol? 
STORY: October 18, 2005:
Ah, yes, savor that next glass of red wine, which many believe will add more years of healthy living for each glass that is consumed. Resveratrol has been identified as the primary molecule responsible for the healthy properties in wine, and is about 10 times more abundant in red than white wine. Studies conducted with alcohol-free red wine, or red wine solids, confirm it's the resveratrol that is the magical molecule in wine. But which form of resveratrol do you prefer, cis or trans? Most of the research involving resveratrol points to trans resveratrol as the molecule that activates the Sirtuin 1 gene, involved in DNA repair and prolongation of life. When exposed to UV light, heat, oxygen, trans resveratrol can photo-isomerize (change molecular structure) and become cis resveratrol, which does not activate the Sirtuin 1 gene. Of interest, when researchers in France recently tested Brazilian wines, they found they contained five times more cis resveratrol than trans. Maybe someday sophisticated wine connoisseurs will ask for red wine with high trans resveratrol content. -Bill Sardi, reporting for Resveratrol News Copyright 2005 J Agric Food Chem. 2005 July13;53(14):56649.
Determination of stilbenes (delta-viniferin, trans-astringin, trans-piceid, cis- and trans-resveratrol, epsilon-viniferin) in Brazilian wines.
Vitrac X, Bornet A, Vanderlinde R, Valls J, Richard T, Delaunay JC, Merillon JM, Teissedre PL.
Universite de Bordeaux 2, Faculte des Sciences Pharmaceutiques, Groupe d'Etude des Substances Vegetales a Activite Biologique, EA 3675, 146, rue Leo Saignat, 33076 Bordeaux Cedex, France.
Phenolics from grapes and wines can play a role against oxidation and development of atherosclerosis. Stilbenes have been shown to protect lipoproteins from oxidative damage and to have cancer chemopreventive activity. We describe a method for the direct determination of stilbenes in several red wines using high-performance liquid chromatography with UV detection. In a survey of 12 commercial wines from the south of Brazil (Rio Grande del Sul), levels of delta-viniferin are reported for the first time in different varieties of red wines. Brazilian red wine contains trans-astringin, trans-piceid, trans-resveratrol, cis-resveratrol (in high quantity: 5 times more than the trans form), epsilon-viniferin, and a compound isolated for the first time in wine, trans-delta-viniferin. Isolation and identification of delta-viniferin was achieved by NMR after extraction and fractionation of red wine phenolics. delta-Viniferin contributes, as well as cis-resveratrol and trans-piceid, to a significant proportion of stilbenes in wine dietary intake, particularly with Merlot varieties containing an average level of 10 mg/L for delta-viniferin, 15 mg/L for cis-resveratrol, and 13 mg/L for trans-piceid. The total stilbene intake from wine origin was estimated for the Brazilian population as 5.3 mg/day per person (on the basis of a regular wine consumption of 160 mL/day). delta-Viniferin can contribute to around 20% of total stilbenes in wine (average of 6.4 mg/L in red Brazilian wines). It would be important in the future to investigate the origins of the differences in wine stilbene levels in relation to the vine varieties, and the bioavailability of the newly extracted stilbene delta-viniferin in plasma after consumption of different types of wines.
=end=
Articles, papers, arguments & opinions, thoughts, all welcome.
Email to: admin@resveratrolnews.com
| MORE ARTICLE
PREVIEWS |
