Antioxidant and vasorelaxant activities induced by northeastern Brazilian fermented grape skins

Abstract

BackgroundIn northeastern Brazil, grape pomace has become a potential alternative byproduct because of the recover phenolic compounds from the vinification process. Comparative analyses were performed between lyophilized extract of grape skins from pomace, described as fermented (FGS), and fresh, unfermented (UGS) grape skins to show the relevant brand’s composition upon the first maceration in winemaking.MethodsThe use of in vitro testing such as Folin-Ciocalteu’s, DPPH free radical scavenger and HPLC methods were performed to evidence antioxidant effect and phenolic compounds. Additionally, vascular reactivity studies were performed in third-order branches of rat superior mesenteric arteries, which were obtained and placed in organ baths containing Krebs-Henseleit solution, maintained at 37 °C, gassed with a mixture of 95% O2 and 5% CO2, and maintained at pH 7.4. The in situ formation of reactive oxygen species (ROS) was evaluated in small mesenteric rings using oxidative fluorescent dihydroethidium dye.ResultsWe found higher phenolic content and antioxidant activity in FGS when compared to UGS. HPLC analyses identified a significant number of phenolic compounds with antioxidant potential in both samples. The vasorelaxant effect induced by FGS was more potent than that induced by UGS, and the activity was attenuated after removal of vascular endothelium or by blockade of endothelium-derived relaxing factors, such as NO and EDHF.ConclusionsThe FGS extract may be a great source of natural polyphenol products with potent antioxidant effects and endothelium-dependent vasodilatory actions involving NO and EDHF pathways.

Polyphenolic Compounds, Antioxidant, and Cardioprotective Effects of Pomace Extracts from Fetească Neagră Cultivar

“…FNFr had a better DPPH IC 50 than FNFs. This observation is consistent with other studies indicating that the fermentation process increases polyphenol releases from the pomace cells [ 56 ]. As phenolic compounds are the most important grape secondary metabolites with antioxidant properties, a high and significant correlation between FNFs and FNFr in vitro antioxidant activities and TPI was found.…”

Phytochemical Profiling, Antioxidant and Cardioprotective Properties of Pinot Noir Cultivar Pomace Extracts

“…As phenolics compounds are the most important grape secondary metabolites with antioxidant properties [39], the polyphenol content of PNFs and PNFr samples correlated with the good antioxidant activity evaluated by DPPH test. In other reports, the fermented pomace had a better DPPH RSA than the unfermented pomace [40]. In our study PNFs and PNFr had similar DPPH RSA.…”

Unveiling the Role of Inflammation and Oxidative Stress on Age-Related Cardiovascular Diseases

“…The literature studies have proven the molecular mechanisms of action of grape and red wine polyphenols against oxidative and inflammatory processes [229,243,244]. Polyphenols inhibit the phosphorylation of MAP kinases, causing a blocking effect on the transcription factors NF-κB and AP-1 and, consequently, blocking the synthesis of TNF-α, interleukins, chemokines, and molecule adhesion.…”