Antioxidant wine-derived

Which subpopulations of blood plasma lipoproteins bind the wine-derived antioxidants ... 

Figure 21 shows the distribution of wine-derived antioxidants between apo B-containing lipoproteins and other high-molecular-weight components of... 

Phenolic substances in red wine were shown to inhibit LDL oxidation in vitro [95]. In previous studies, red wine-derived phenolic acids [115,116], resveratrol [117], flavonols (quercetin, myricetin) [68,118,119], catechins [66,120], and the grape extract itself [121,122] have been shown to possess antioxidant properties. The finding that ethanol and wine stripped of phenols did not affect LDL oxidation further confirmed that the active antioxidant components in red wine are phenolic compounds [123]. Red wine fractionation revealed major antioxidative potency to monomeric catechins, procyanidins, monomeric anthocyanidins, and phenolic acids [123]. The flavonol quercetin and the flavonol catechin were both tested for antioxidative and antiatherogenic effects in the atherosclerotic E° mice [111]. E° mice at the age of 4 weeks were supplemented for up to 6 weeks in their drinking water with placebo (1.1% alcohol) or with catechin or quercetin (50 pg/day/mouse). The atherosclerotic lesion area was smaller by 39% or by 46%, respectively, in the treated mice than in E° mice that were treated with placebo (Fig. 4A-E). 

These assays measure the level of protection provided to the naturally occurring carotenoid derivative crocin from bleaching by the radical generator AAPH. The assay was originally suggested by Bors and others (1984) and modified by Tubaro and others (1998), who used it to show that plasma antioxidant capacity is deeply influenced by the consumption of wine. The addition of a sample containing chain-breaking antioxidants results in the decrease in the rate of crocin decay. The sample is monitored for 10 min at 443 nm. 

Resveratrol is another type of polyphenol, a stilbene derivative, that has assumed greater relevance in recent years as a constituent of grapes and wine, as well as other food products, with antioxidant, anti-inflammatory, anti-platelet, and cancer preventative properties. Coupled with the cardiovascular benefits of moderate amounts of alcohol, and the beneficial antioxidant effects of flavonoids, red wine has now emerged as an unlikely but most acceptable medicinal agent. 

Cartron E, Fouret G, Carbonneau M-A, Lauret Cel, Michel Fco, Monnier L, Descomps B, Leger CL. 2003. Red-wine beneficial long-term effect on lipids but not on antioxidant characteristics in plasma in a study comparing three types of wine— description of two O-methylated derivatives of gallic acid in humans. Free Radic Res 37 1021-1035. 

Another important field of application concerns food and beverages, especially wine, juices, and tea (A2, A11, A17, B4, K12, V7, Yl). The antioxidant components of food include vitamin E (a-tocopherol), vitamin A (retinoids), vitamin C (ascorbic acid), and also fi-carotene (provitamin A), other carotenoids (of which more than 600 compounds have been identified), flavonoids, simple phenols, and glucobrasicins (H3). Unfortunately, the TAC value of a food is not informative on the bioavailability of its antioxidants. It has been estimated that polyphenols are normally present in blood plasma at concentrations of 0.2-2 //M (PI). However, it has been demonstrated that feeding rats a quercetin-augmented diet can increase their plasma levels of quercetin and its metabolites up to 10-100 //M (M27), and transient increases in the concentration of plant-derived phenolic compounds can take place after ingestion of food and beverages, which may affect blood plasma TAC (see later). 

Due to the concentrating effect of noble rot as well as the maceration widely used before pressing, these wines are rich in polyphenols. They provide more antioxidants than other white wines. This particularly applies to Tokaji Aszu, where maceration occurs in an alcohol medium (fermenting must or young wine). However, the concentration of resver-atrol and its derivatives is not significantly higher than in normal white wines, due to their decomposition by Botrytis oxidases. 

The beneficial effects of wine may not be attributable to a single polyphenol but rather to the complex mixture of polyphenols it contains. There is evidence that antioxidant properties underlie most of the effects of wine, but at the same time, certain effects cannot be mimicked by common dietary antioxidants. Although polyphenols are not a panacea, those present in red grape and its derivatives appear to exert beneficial effects on health. 

Trans-resveratrol (trans-3,5,4 -trihydroxystilbene) is a non-flavonoid polyphenol found in grapes, mulberries, and other food prod-ucts. It is responsible for the antioxidant activity of red wine. Intake of moderate amount of red wine has been found to reduce the risk of cardiovascular diseases. In addition to antioxidant activity, resveratrol could inhibit platelet aggregation, and showed anticancer activity. The phenoxyl radicals of resveratrol produced during oxidation by hydroxyl radicals, one-electron oxidants, and peroxyl radicals showed absorption maximum at 410 nm (Fig. I). Reports indicate that trans-resveratrol is a better radical scavenger than vitamins E and C and its activity is similar to that of the flavonoids epicatechin and quercetin. From the comparison of the spectral and kinetic properties of the transients derived from trans-resveratrol and its analogues, it could be concluded that in the neutral and acidic solutions, the para-hydroxy... 

Evaluation of olive- and grape-based natural extracts as potential preservatives for food was carried out by Serra et al. (2008). The antimicrobial activities of two waste-derived extracts, from olive oil and wine production, both rich in polyphenols, and three standard well recognized antioxidants (quercetin, hydroxytyrosol, and oleuropein) were investigated against five microbial species (Escherichia coli, Salmonella poona, Bacillus... 

In grapes, and derived food products (grape juice, wine), the presence of the antioxidant stilbenoid resveratrol (Fig. 5) has also been reported [23-26]. 

Some chemists are saying that the phenolics, natural antioxidants, in nonalcoholic wine prevent cholesterol molecules from forming and clogging the arteries. Phenolics are also found in fresh fruits and vegetables such as raisins, grapes, and onions. At the same time, other scientists say benefits are derived by beer drinkers therefore, it must be alcohol that provides the benefits. 

Fuhrman, B., N. Volkova, A. Suraski, M. Aviram. (2001). White wine with red winelike properties increased extraction of grape skin polyphenols improves the antioxidant capacity of the derived white wine. Journal of Agricultural and Food Chemistry 49 (7), 3164-3168. 

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