Vitis vinifera L. Leaves as a Source of Phenolic Compounds with Anti-Inflammatory and Antioxidant Potential

Abstract

Vitis vinifera is a plant known since ancient times mainly for the interest of its fruits. However, its leaves have traditionally been consumed as food in some regions of the Mediterranean basin and as a medicinal remedy. In this work, the phytochemical profile of this part of the plant, which is considered a bio-residue of viticultural processes, was analyzed (UHPLC-ESI(±)-QTOF-MS). Hydroxybenzoic acids, flavonols, and stilbenes are the main phenolic compounds identified. Its antioxidant and anti-inflammatory capacity were studied both in vitro and in cell culture. Grapevine leaves have a high capacity to scavenge free radicals, as well as to reduce oxidative stress induced by H2O2 in the HepG2 cell line. On the other hand, the methanolic extract of these leaves is capable of inhibiting lipoxygenase, an enzyme involved in inflammatory responses, with an IC50 of 1.63 μg/mL. In addition, the extract showed potent inhibition of NO production in LPS-stimulated RAW 264.7 cells. These results pointed out V. vinifera leaves as a powerful functional food with a high content of biologically active compounds. The enhancement of these by-products can be highly beneficial to food systems and contribute to the development of sustainable agriculture.