Potential application of grape (Vitis vinifera L.) stem extracts in the cosmetic and pharmaceutical industries: Valorization of a by-product

Abstract

Wastes from the wine industry can cause sustainably problems, thus requiring their reuse. Thus, new products can be generated through these wastes, giving environmental, social, and economic advantages. In this sense, the objective of this work was to determine the phenolic composition of six varieties of grape stem extracts by High Performance Liquid Chromatography and to evaluate their biological activities (antioxidant, antimicrobial, anti-inflammatory, and anti-aging). The results showed that grape stem extracts confirm to be a potential source of phenolic compounds, with catechin being the most abundant compound in all varieties (0.44 ± 0.02–2.03 ± 0.08 mg/g dry weight). The grape stem extracts also presented antioxidant activity, reaching values up to 0.84 ± 0.06, 0.64 ± 0.05, and 1.03 ± 0.06 mmol Trolox/g dry weight for ABTS, DPPH, and FRAP assays, respectively. Concerning antimicrobial activity, the extracts presented high efficacy against foot wound ulcers Gram-positive bacteria. In addition, the extracts presented anti-inflammatory capacity exhibiting inhibitions of Nitric Oxid production, by lipopolysaccharide-stimulated macrophages, up to 35.25 %, and revealed, for the first time, anti-aging effect by inhibiting anti-tyrosinase (∼54 %) and anti-elastase (∼98 %) activities. Therefore, grape stem has demonstrated its biological potential, being of interest for cosmetic, pharmaceutical, and food industries.