Study on the Chemical Composition and the Biological Activities of Vitis vinifera Stem Extracts

Abstract
Vitis vinifera (V. vinifera) is a herbaceous plant, cultivated worldwide and known for its biological benefits. The aim of this study is the investigation of the chemical composition as well as the determination of the biological potential of different grape stem extracts obtained by maceration and accelerated solvent extraction (ASE). The HPLC analysis of the tested extracts led to the identification of 28 compounds of which 17 were identified for the first time in grape plants, in addition to seven revealed in the stem part for the first time. Twenty-nine volatile molecules have been detected by GC-MS in the grape stem part; among them seven were identified for the first time in the grape plant. For the biological analysis, the ethyl acetate extract (EtOAc) obtained by maceration showed a significant potential regarding antioxidant activity (IC50 = 42.5 µg/mL), anti-Alzheimer (IC50 = 14.1 µg/mL), antidiabetic (IC50 = 13.4 µg/mL), cytotoxic with HCT-116 (IC50 = 12.5 µg/mL), and anti-inflammatory (IC50 = 26.6 µg/mL) activities, as well as showing the highest polyphenol content (207.9 mg GAE/g DW).