Simultaneous determination of polyphenolic compounds in red and white grapes grown in Sardinia by high performance liquid chromatography-electron spray ionisation-mass spectrometry

A new method for the identification and the quantification of nonanthocyanin phenolic compounds from six Vitis Vinifera grape varieties native to Sardinia (three native: Vermentino, Malvasia and Cannonau and three non-native types: Chardonnay, Sauvignon and Cabernet Sauvignon; Argiolas vineyard) was developed. This rapid and selective method employs LC/ESI-MS in negative mode. Different solvents extraction and different sorbents for purification were compared to the direct analysis of the initial extracts without further sample preparation. A total of 54 phenolic compounds were identified either in the freeze-dried skins or seeds, including nonflavonoids (hydroxybenzoic and hydroxycinnamic acids and their derivatives, stilbenes) and flavonoids (flavanols, flavonols, dihydroxyflavonols). (C) 2009 Elsevier B.V. All rights reserved

Antioxidant properties of the phenolic fraction of Sardinian wines

The aim of this study was to compare the antioxidant capacities of the phenolic fraction of wines from Vitis vinifera grapes cultivated in Sardinia (three native: Cannonau, Malvasia, Vermentino and three non-native types: Cabernet-sauvignon, Chardonnay and Sauvignon), in simple in vitro systems. All the extracts showed a significant antioxidant activity, beeing the native wine extracts the most active in inhibiting the lipid peroxidation process

A selection of grapes from Sardinia: antioxidant properties

Several studies have suggested that grape extracts possess different biological actions and may be beneficial in the prevention of many human diseases, associated with oxidative stress; however rather scarce data on the biological properties of the countless varieties of grapes growing in Sardinia are available. Grape and wine extracts are known to contain high levels of polyphenolic compounds. Polyphenols have been proposed to exert beneficial effects in a multitude of disease states, including cancer, cardiovascular diseases and neurodegenerative disorders. Many of the biological actions of polyphenols have been attributed to their antioxidant properties. In the present study we investigated the antioxidant effect of extracts from 6 varieties of grape growing in Sardinia (Cannonau, Cabernet-sauvignon, Malvasia, Vermentino, Chardonnay, Sauvignon), in simple in vitro systems, during autoxidation of linoleic acid at 37 degrees C and during cholesterol oxidation at 140 degrees C, in the absence of solvent. The cytotoxicity and the capacity of grape extracts to inhibit MDA production were evaluated in the human colon adenocarcinoma cell line, Caco-2. This cell line spontaneously undergoes full differentiation in vitro with enterocyte-like features and has been recognized as a suitable model for evaluating the effect of nutrient components. All tested grape extracts showed no cytotoxicity in the range 25-100 mu g/ml and showed a significant antioxidant activity, beeing the native grape extracts from Sardinia the most active

Wine extracts from Sardinian grape varieties attenuate membrane oxidative damage in Caco-2 cell monolayers

One of the most important sites of polyphenol action seems to be in the gastrointestinal system before absorption. We investigated the ability of three wine phenolic extracts, obtained from grape varieties grown in Sardinia, Cannonau (red), Vermentino and Malvasia (white), to exert an antioxidant action against tert-butyl hydroperoxide (TBH)-induced oxidative damage to Caco-2 cell monolayers as a model system of the human intestine. TBH treatment caused the disruption of epithelial integrity, measured as transepithelial electrical resistance, and markers of the peroxidation process of membrane lipids, MDA, fatty acid hydroperoxides and 7-ketocholesterol. All wine extracts were able to counteract the oxidising action of TBH and, in spite of the differences in phenolic composition, exerted a comparable activity. Our findings point out a direct antioxidant action of the wine extracts on enterocytes exposed to oxidising species and further support the opinion that total phenolic content is not essential for antioxidant activit

Inhibition of hepatitis C replicon RNA synthesis by beta-d-2\u27-deoxy-2\u27-fluoro-2\u27-C-methylcytidine: a specific inhibitor of hepatitis C virus replication

β-D-2′-Deoxy-2′-fluoro-2′-C-methylcytidine (PSI-6130) is a cytidine analogue with potent and selective anti-hepatitis C virus (HCV) activity in the subgenomic HCV replicon assay, 90% effective concentration (EC90)=4.6 +2.0 µM. The spectrum of activity and cytotoxicity profile of PSI-6130 was evaluated against a diverse panel of viruses and cell types, and against two additional HCV-1b replicons. The S282T mutation, which confers resistance to 2′-C-methyl adenosine and other 2′-methylated nucleosides, showed only a 6.5-fold increase in EC90. When assayed for activity against bovine diarrhoea virus (BVDV), which is typically used as a surrogate assay to identify compounds active against HCV, PSI-6130 showed no anti-BVDV activity. Weak antiviral activity was noted against other flaviviruses, including West Nile virus, Dengue type 2, and yellow fever virus. These results indicate that PSI-6130 is a specific inhibitor of HCV. PSI-6130 showed little or no cytotoxicity against various cell types, including human peripheral blood mononuclear and human bone marrow progenitor cells. No mitochondrial toxicity was observed with PSI-6130. The reduced activity against the RdRp S282T mutant suggests that PSI-6130 is an inhibitor of replicon RNA synthesis. Finally, the no-effect dose for mice treated intraperitoneally with PSI-6130 for six consecutive days was ≥100 mg/kg per day