Exploiting bioderived humic acids: A molecular combination with ZnO nanoparticles leads to nanostructured hybrid interfaces with enhanced pro-oxidant and antibacterial activity

Waste to Wealth Approach: Improved Antimicrobial Properties in Bioactive Hydrogels through Humic Substance–Gelatin Chemical Conjugation

“…Indeed, the combination of HS with gelatin preserves their intrinsic antibacterial activity. This is bound to be exerted through the synergy between bacterial membrane destabilization and ROS production. , Notably, carboxylic and phenolic groups in HS could increase the number of hydrogen bonds with cell bacterial membranes . This higher affinity should induce irreversible modifications in its lipid structure, enhancing the permeability of ROS, which are produced by quinone redox equilibria in HS, with a consequent reduction in pathogenic strain growth and their death .…”

“…12−14 Reversible redox chemistry of quinone moieties accounts for both antioxidant and prooxidant activities of these bioavailable mixtures because of their ability to generate, stabilize, or scavenge reactive oxygen species ( • OH, • O 2 − , and • OOH), also known as ROS. 15 Furthermore, the amphiphilic nature of HSs determines selfassembly in an aqueous environment, 16−18 building up supramolecular structures which can act as metal chelating agents 19,20 and can interact with organic contaminants. 21−23 Despite the substantial potential offered by bioavailable HS mixtures, their full technological exploitation is strongly limited by their segregation leakage and/or degradation phenomena in an aqueous environment.…”

“…They are viewed as a promising and cost-effective source for high-value products and novel biocompatible materials for a wide range of applications spreading from environmental to biomedical field because of their intriguing properties. Phenolic and carboxylic groups in HSs are primarily responsible for improved plant growth and nutrition, − flame retardancy features due to char formation in combustion processes, , metal ion chelation, and even redox behavior, providing for remarkable antioxidant, antiviral, and anti-inflammatory activities. − Reversible redox chemistry of quinone moieties accounts for both antioxidant and pro-oxidant activities of these bioavailable mixtures because of their ability to generate, stabilize, or scavenge reactive oxygen species ( • OH, • O 2 – , and • OOH), also known as ROS …”

Nanoparticle Coatings on Glass Surfaces to Prevent Pseudomonas fluorescens AR 11 Biofilm Formation

“…Hybrid melanin-ZnO: a solvothermal synthesis route previously defined [ 39 ] was used to produce bare and hybrid Mel/ZnO nanoparticles as well. Briefly, zinc acetate dihydrate (ZAD, 1.815 g) was dissolved into 101.3 mL of a mixture of TEA and ethanol (2.3% v / v in TEA).…”

“…Thermogravimetric analysis (TGA) was carried out by using a simultaneous thermo-analyser SDT Q600 (TA Instrument, New Castle, DE, USA) in order to assess the presence and amount of the organic component within both Mel/TiO 2 and Mel/ZnO samples. Quantitative analysis was performed according to the standard test methods for proximate analysis [ 40 ] and by following a previously described protocol [ 39 ].…”