The “End Life” of the Grape Pomace Waste Become the New Beginning: The Development of a Virtuous Cycle for the Green Synthesis of Gold Nanoparticles and Removal of Emerging Contaminants from Water

Abstract

During the last decades, the demand for processes developed according to the Circular Economy Principles has increased, searching for an alternative life for wastes. For this purpose, a one-pot green approach is exploited during this work to synthesize gold nanoparticles (AuNPs) by using grape pomace waste from Vitis vinifera. A raw aqueous extract of grape seeds, skin, and stems is used for AuNPs synthesis. UV-Vis, XPS, SEM, and ATR-FTIR spectroscopies demonstrate the main role of the extract’s polyphenolic components in stabilizing nanoparticles. XRD, DLS, and Zeta Potential analyses were used to characterize AuNPs. Moreover, the ionic strength, pH, and temperature role was investigated through the Surface Plasmon Resonance (SPR) band observation to assess AuNPs’ stability and photostability. For foreseeing the as-synthesized AuNPs’ potential use in cosmetic and biomedical fields as multifunctional platforms, their antioxidant, and skin-lightening properties were tested, together with their sunscreen ability. A preliminary in-vitro evaluation is reported about the AuNPs’ cytoprotective effects against H2O2 oxidative stress-induced in normal human dermal fibroblasts. Briefly, the possibility of reusing the grape pomace waste after the AuNPs synthesis as an adsorbent for the efficient removal of emergent contaminants is preliminarily discussed in the paper, further valorizing the use of waste according to a bio circular approach.

Exploring the Potential of Grape Pomace Extract to Inhibit Thermo-Oxidative Degradation of Sunflower Oil: From Routine Tests to ATR-FTIR Spectroscopy

“…These differences could be assigned to the presence of polyphenolic compounds and BHT in SFO samples. In accordance with the literature, the infrared profile of grape pomace extract revealed the absorption bands with peaks around 2850 cm −1 and 2920 cm −1 assigned to both symmetric and asymmetric stretching vibrations of C–H bonds from (CH 2 ) groups, as usually observed for phenolic compounds [ 68 ]. Absorption bands around 2956 cm −1 and 2872 cm −1 due to asymmetric and symmetric stretching vibrations of methyl group are also characteristic of the BHT spectrum [ 69 ].…”

Investigation regarding the potential application of grape pomace extracts on in vitro plant growth and development

“…Data registered from IR profile of hydroalcoholic grape pomace extracts (Figure 3) are in accordance with the literature [39,40]. It can be observed the peaks around 2900-3000 cm -1 , which relates to the C-H groups vibrations, usually observed for phenols.…”

“…It can be observed the peaks around 2900-3000 cm -1 , which relates to the C-H groups vibrations, usually observed for phenols. The band at 3320 cm −1 indicates the involvement of the OH groups [40]. The peaks around 1514 cm -1 represent aromatic squeal vibration and around 1100 cm -1 aromatic CH in plane bending vibration.…”

Pulsed electric fields-assisted extraction of valuable compounds from red grape pomace: Process optimization using response surface methodology

“…where: 5 ; MW (molecular weights of cyanidin-3-glucoside) = 449.2 g/mol; DF = dilution factor; ε = (molar extinction coefficient) = 26900 L/mol/cm; 10 3 = conversion factor from g to mg; L/S = liquid-to-solid ratio; m TOT /m DW = ratio between the total mass of fresh grape pomace and the mass of dry grape pomace.…”

“…World wine production in 2021, excluding juices and musts, is estimated at 260 MhL, with 19.3% produced by Italy, which represents the major wine producer. During the winemaking process, however, besides wine production, about 20-30% of the processed grapes is disposed of as wastes and by-products (5). Among these, grape pomace, a mixture of skins, pulp, seeds, and stalks, represents the most abundant by-product derived from the winemaking process (6).…”