Grape Pomace: Antioxidant Activity, Potential Effect Against Hypertension and Metabolites Characterization after Intake

Observational studies indicate that the intake of polyphenol-rich foods improves vascular health, thereby significantly reducing the risk of hypertension and cardiovascular disease (CVD). Therefore, the aim of this study was to analyse the remained potential of grape by-products from important Rhône Valley red wine cultivars: Grenache, Syrah, Carignan, Mourvèdre and Alicante. For that, six different extracts from grape pomaces, selected by their antioxidant activity, were studied in vivo during six weeks with spontaneously hypertensive rats (SHR). Extracts used in SHR1, SHR2 and SHR6 groups presented a « rebound effect » on systolic blood pressure, whereas the other extracts do not change it significantly. The bioavailability of Grenache (GRE1) (EA70) seed pomace extract (SHR1 group), Mouvendre (MOU) (EA70) skin pomace extract (SHR5 group) and Alicante (ALI) (EA70) skin pomace extract (SHR6 group) was studied by High Performance Liquid Chromatography with Photodiode Array detector and Electrospray Ionization Mass Spectrometer (HPLC-PDA-ESI-MS(n)) in urine, plasma and tissues to search differences on the metabolism of the different extracts intake.