Humic extracts from raw or composted coffee husks as novel chitosan crosslinkers for the synthesis of sustainable nanoparticles with antioxidant properties.

Coffee husks have been valorised by isolating humic materials before (HLS-Raw) or after (HS-Comp) composting them. Such substrates were reacted with chitosan at different ratios to synthesize novel nanoparticles (NP) with radical scavenging properties. Size and antioxidant activity of nanomaterials increased at higher HS/chitosan ratio, while zeta potential decreased.

Use of Natural Agents and Agrifood Wastes for the Treatment of Skin Photoaging.

Photoaging is the premature aging of the skin caused by repeated exposure to ultraviolet (UV) rays. The harmful effects of UV rays-from the sun or from artificial sources-alter normal skin structures and cause visible damage, especially in the most exposed areas. Fighting premature aging is one of the most important challenges of the medical landscape.

Prokaryotic Diversity of the Composting Thermophilic Phase: The Case of Ground Coffee Compost.

Waste biomass coming from a local coffee company, which supplied burnt ground coffee after an incorrect roasting process, was employed as a starting material in the composting plant of the Experimental Station of the University of Naples Federico II at Castel Volturno (CE). The direct molecular characterization of compost using C-NMR spectra, which was acquired through cross-polarization magic-angle spinning, showed a hydrophobicity index of 2.7% and an alkyl/hydroxyalkyl index of 0.

Bio-Based Hydrogels Composed of Humic Matter and Pectins of Different Degree of Methyl-Esterification.

We prepared humo-pectic hydrogels through ionotropic gelation by crosslinking natural pectins of different degree of methyl-esterification with either humic substances (HS) extracted from cow manure compost or humic-like substances (HULIS) from depolymerized lignocellulose biorefinery waste. The hydrogels were characterized by solid-state C-NMR spectroscopy, scanning electron microscopy, spectroscopic magnetic resonance imaging and rheological analyses. Their ability to work as controlled release systems was tested by following the release kinetics of a previously incorporated model phenolic compound, like phloroglucinol.

Soil washing with solutions of humic substances from manure compost removes heavy metal contaminants as a function of humic molecular composition.

Humic Substances (HS) from Leonardite and two different composts were used as biosurfactants to wash heavy metals (Cu, Pb, Zn, Cd, Cr) from a soil added with two metals concentrations and aged for 4 and 12 months. Composts were obtained by mixing manure with either 40 (CM-I) and 20 (CM-II) % of straw as structuring material. For both aging periods and both metal concentrations, HS from CM-I removed more metals than from Leonardite, whereas the washing capacity of HS from CM-II was negligible.