A multistep extraction process was proposed to recover polyphenols, reducing sugars, and soluble lignin from vine shoots. A physical pretreatment by high voltage electrical discharges (HVED) was followed by an enzymatic hydrolysis and a final delignification step by alkaline hydrolysis. HVED before enzymatic hydrolysis enhanced the extraction of polyphenols (+72%), reducing sugars (+43%), and soluble lignin (+104%) as compared to control experiments (enzymatic hydrolysis). HVED also reinforced the subsequent delignification process by reducing 10% lignin content in exhausted residues. Identification and quantification of ferulic acid, resveratrol, p-coumaric acid, and hydroxybenzoic acid were carried out using high-performance liquid chromatography.
Rajha, H. N., El Kantar, S., Afif, C., Boussetta, N., Louka, N., Maroun, R. G., & Vorobiev, E. (2018). Selective multistage extraction process of biomolecules from vine shoots by a combination of biological, chemical, and physical treatments. Comptes Rendus Chimie, 21(6), 581–589. https://doi.org/10.1016/j.crci.2018.02.013