Valorization of Kiwi Peels: Fractionation, Bioactives Analyses and Hypotheses on Complete Peels Recycle

Abstract

Kiwi fruit samples (Actinidia deliciosa Planch, cv. Hayward) represent a suitable and good source for fibers obtainment as well as for polyphenolic and carotenoid extraction. With this aim, in this study they were submitted to a double phase extraction to separate insoluble fibers by an organic phase containing lipophilic substances and an hydroalcoholic phase containing polyphenols and soluble fibers. Insoluble fibers could be separated by filtration and sent to be micronized and reused. Hydroalcoholic fractions were then furtherly fractionated by solid-phase extraction. Data coming from the color CIEL*a*b* and the HPLC-DAD analyses of the extracts were compared and correlate with those coming from the SPME-GC/MS analysis of either the finely shredded peels or of the extracts. The obtained extracts were also submitted to anti-radical activity evaluation and anti-Candida activity. Results show that all of the obtained residues are value added products. Hypotheses were also made about the nature and the possible recycle of the obtained purified solid residue.

In-Depth Chemical Characterization of Punica granatum L. Seed Oil

“…Only very weak signals of DAGs were observed in the 590–620 m/z range, whereas ionic species corresponding to TAGs can be highlighted in the 830–915 m/z region. The near absence of DAG species in this pomegranate oil extract is an exception to the results reported in the literature [ 26 ] according to which, DAG ionic signals are more represented than TAG peaks. Evidently, neither the Soxhlet nor the supercritical extraction conditions we applied, caused hydrolysis of the triglyceride component.…”

“…The polyphenol’s extracts (SPE Soxhlet oil, 1b and SPE scCO 2 oil, 2b ) were weighed, solubilized in methanol (0.5 mg/mL) and filtered with a Millex ® —LG filter (Low Protein Binding Hydrophilic PTFE 0.20 µM Membrane) (Merck Science Life, S.r.l, Milan, Italy). The solutions were injected and analyzed with an HPLC-DAD (Perkin Elmer, Milan, Italy), equipped as reported in Cairone et al (2022) [ 26 ]. The analyses were performed at 280 and 360 nm on a Luna RP-18 3µ column, in gradient from 100% solvent A (water at 5% formic acid) to 85% in 15 min, from 85 to 55% in 30 min and from 55 to 40% in 20 min, at a flow rate of 0.8 mL/min.…”

WITHDRAWN: Biosynthesis of silver nanoparticles using Actinidia deliciosa peels extract: Optimization, characterization, and catalytic activity for methylene blue dye degradation

“…One of the agro-waste that has been utilized in the biosynthesis of nanoparticles is the kiwifruit (Actinidia deliciosa) peels that are rich in polyphenols and other antioxidants. In fact, the peels of the kiwifruit have been employed for the biofabrication of several nanoparticles such as zinc oxide, titanium oxide and tin oxide nanoparticles [23]. Therefore, the aim of the current investigation is to assess the utility of the aqueous extract of kiwifruit peels as a bioreducing and capping agent for the biogenic synthesis of AgNPs.…”

Catalytic Degradation Efficacy of Silver Nanoparticles Fabricated Using Actinidia deliciosa Peel Extract

“…One of the agro-waste that has been utilized in the biosynthesis of nanoparticles is the kiwifruit (Actinidia deliciosa) peels that are rich in polyphenols and other antioxidants. In fact, the peels of kiwifruit have been employed in the biofabrication of several nanoparticles, such as zinc oxide, titanium oxide, and tin oxide nanoparticles [23]. Therefore, the aim of the current investigation is to assess the utility of the aqueous extract of kiwifruit peels as a bioreducing and capping agent for the biogenic synthesis of AgNPs.…”