Harnessing the wine dregs: An approach towards a more sustainable synthesis of gold and silver nanoparticles

• Published in: Journal of photochemistry and photobiology. B, Biology Biology, 2018-01, Vol.178, p.302-309
• Main Authors: González-Ballesteros, N., Rodríguez-González, J.B., Rodríguez-Argüelles, M.C.
• Format: Article
• Language: English
• Subjects: AgNP; AuNP; Bioactive compounds; Biomolecules; Electron microscopy; Food processing; Fourier transforms; Functional groups; Gold; Grape pomace; Infrared spectroscopy; Nanomaterials; Nanoparticles; Nanotechnology; Phenolic compounds; Phenols; Silver; Spectroscopy; Synthesis; TEM; Transmission electron microscopy; UV–Vis; Vitis vinifera; Vitis vinífera; Waste disposal; Wine; Wines
• ISSN: 1011-1344; 1873-2682
• DOI: 10.1016/j.jphotobiol.2017.11.025

In recent years, the management of food waste processing has emerged as a major concern. One such type of food waste, grape pomace, has been shown to be a great source of bioactive compounds which might be used for more environmentally - friendly processes for the synthesis of nanomaterials. In this study, grape pomace of Vitis vinifera has been used for the obtainment of an aqueous extract. Firstly, the reducing activity, total phenolic content and DPPH scavenging activity of the aqueous extract were determined. Then, the aqueous extract was used for the synthesis of gold and silver nanoparticles. The formation of spherical and stable nanoparticles with mean diameters of 35.3±5.2nm for Au@GP and 42.9±6.4nm for Ag@GP was confirmed by UV–vis spectroscopy and transmission electron microscopy. Furthermore, the functional group of biomolecules present in grape pomace extract, Au@GP and Ag@GP, were characterized by Fourier transform infrared spectroscopy prior to and after the synthesis, in order to obtain information about the biomolecules involved in the reducing and stabilization process. This study is the first to deal with the use of Vitis vinifera grape pomace in obtaining gold and silver nanoparticles through an eco-friendly, quick, one-pot synthetic route. [Display omitted] •Aqueous extract of grape pomace served to synthesize gold and silver nanoparticles.•Reducing power, TPC and DPPH activity of the GP aqueous extract were determined.•The formation of spherical and stable nanoparticles was confirmed by UV–Vis and TEM.•TEM images provided diameters of 35.3±5.2nm for Au@GP and 42.9±6.4nm for Ag@GP.•The biomolecules present in GP, Au@GP and Ag@GP were characterized by FTIR.