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The emergence of antimicrobial resistance in foodborne bacterial pathogens has raised significant concerns in the food industry. This study explores the antimicrobial potential of biosynthesized silver nanoparticles (AgNPs) derived from Agaricus bisporus (Mushroom) against foodborne bacterial pathogens. The biosynthesized AgNPs were characterized using various techniques, including UV–visible spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, high-resolution scanning electron microscopy with energy dispersive X-ray spectroscopy, dynamic light scattering, and zeta potential analysis. The antibacterial activity of the AgNPs was tested against a panel of foodborne bacterial strains, and their cytotoxicity was evaluated on normal human skin fibroblasts. Among the tested strains, Pseudomonas aeruginosa ATCC 27853 showed the highest sensitivity with an inhibition zone diameter (IZD) of 48 mm, while Klebsiella quasipneumoniae ATTC 700603 and Bacillus cereus ATCC 11778 displayed the highest resistance with IZDs of 20 mm. The silver cations released by AgNPs demonstrated strong bactericidal effects against both Gram-positive (G + ve) and Gram-negative (G − ve) bacteria, as evidenced by the minimum inhibitory concentration/minimum bactericidal concentration (MBC/MIC) ratio. Moreover, cytotoxicity testing on normal human skin fibroblasts (HSF) indicated that AgNPs derived from the mushroom extract were safe, with a cell viability of 98.2%. Therefore, AgNPs hold promise as an alternative means to inhibit biofilm formation in the food industry sector. [ABSTRACT FROM AUTHOR]

Polyphenolics have been predicted to effectively develop antimicrobial agents for the food industry as food additives and promote human health. This study aims to synthesize pomegranate peel extract (PPE) with silver nanoparticles (AgNPs) against eight foodborne pathogens. Multispectroscopic analysis of UV–vis spectroscopy, Zeta potential, Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) analysis were used to characterize the interaction between PPE and AgNPs. Eight foodborne pathogenic strains (six bacterial and two fungal strains) Bacillus subtilis ATCC 6633, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 8379, Klebsiella pneumoniae ATCC 00607, Salmonella typhi DSM 17058, Shigella sonnei DSM 5570, Aspergillus flavus ATCC 9643, and Rhizopus oryzae ATCC 96382 were used to test the inhibitory potential of PPW-AgNPs. The reaction colour of PPE-AgNPs from yellow to brown indicated that the nanoparticles were successfully formed. The UV absorption of PPE-AgNPs was detected at 440 nm of 0.9 SPR. SEM image of PPE-AgNPs exhibited spherical shapes with a zeta potential of − 20.1 mV. PPE-AgNPs showed high antimicrobial activity against all tested strains. The highest inhibition activity of PPE-AgNPs was recorded for the B. subtilis strain followed by K. pneumonia, while the highest resistance was noticed for R. oryzae. The components of pomegranate peel were analyzed using gas chromatography–mass spectrometry (GC–MS). The major constituents of pomegranate peel is phenol (51.1%), followed by Isocitronellol (19.41%) and 1-Propanol, 2-(2-hydroxypropyl)- (16.05%). PPE is key in the simple, eco-friendly green synthesis of extracellular stable AgNPs as an alternative source for harmful chemical disinfectants. [ABSTRACT FROM AUTHOR]

Four chitosan‐poly(vinyl chloride), Cs‐PVC, conjugates were synthesized by primarily reacting amino‐PVC with chloroacetyl chloride to give 2‐chloro‐N‐(2‐aminoethyl) acetamide‐functionalized PVC (PVC‐AcCl) followed by conjugation with chitosan to yield a derivative of acetamide‐functionalized PVC chitosan (Cs‐AcPVC). On the other hand, a one‐pot reaction between PVC‐chloroacetyl chloride, benzimodazole, and chitosan produced benzimodazole‐functionalized PVC conjugates (PVC1). The above one‐pot reaction was repeated with incorporating silver nanoparticles, AgNPs, via in situ reduction of Ag salt to give PVC2 whereas silver treated titanium dioxide (Ag/TiO2)NPs was simply mixed with PVC1 to afford PVC3. Fourier‐transform infrared spectroscopy FTIR spectroscopic analyses of all the synthesized materials were studied. Morphological investigation such as scanning and transmission electron microscopy, and thermal gravimetric analysis were also carried out. The antibacterial activities of the synthesized conjugates were investigated against two Gram‐negative (Escherichia coli, and Salmonella typhimurium) and two Gram‐positive (Staphylococcus aureus, and Listeria monocytogenes) bacterial strains. The antibacterial assay showed that all PVC‐Cs conjugates exhibited excellent bacterial inhibition (five‐log10 reduction) at a concentration of 500 mg/L after 30 min and almost complete inhibition after 120 min. Minimum inhibition concentration investigation showed that conjugates PVC‐chloroacetyl chitosan and PVC3 were more potent than PVC1 and PVC2 against both Gram‐negative and Gram‐positive strains at 250 mg/L. These results suggested that all four polymeric conjugates might afford a revolutionary antibacterial polymeric material that can be useful in many applications such as water sanitization, food packaging, and biomedical devices. [ABSTRACT FROM AUTHOR]

Introduction Thermo-responsive hydrogels are promising biomedical systems as their gelation is triggered by temperature changes. Greenly synthesized noble metallic nanoparticles are a growing research area assessing their potential applications in nanomedicine. Materials and methods Chitosan/phosphate thermosensitive gels were successfully achieved. The developed composite scaffolds were functionalized with the greenly synthesized Ag or Ag@Pd targeting improved bactericidal activity and biocompatibility performance. The physicochemical characterization was assessed through TGA, DSC, FESEM, HRTEM, XRD and FTIR. Bactericidal activities were tested against gram- positive Staphylococcus aureus and gram-negative Pseudomonas aeruginosa . Their biodegradability upon DMEM immersion was followed up to seven days through measuring ionic concentrations of Ca, P, Ag and Pd successively. Key findings The newly developed phosphatic layers over the scaffold surfaces post-immersion assessed their osteogenic ability. Further, their promising and differentiated bactericidal activities due to the noble metals incorporation were proved. Cytotoxicity assessment demonstrated their high biocompatibility since no toxic effect was recorded. Significance Consequently, they can be successfully and directly applied in biomedical and dental surgeries. [ABSTRACT FROM AUTHOR]

Abstract We herein describe the synthesis of four Cs-PVC conjugates three of them were functionalized with benzothiazole (BTh) derivative as an antibacterial agent. Two of these BTh-functionalized conjugates, namely Cs2 and Cs3, comprise silver nanoparticles (AgNPs) and Ag/TiO 2 NPs, respectively. The structures were characterized via FTIR spectroscopic analysis, morphological investigation such as scanning (SEM) and transmission (TEM) electron microscopy, and thermal gravimetric analysis (TGA). Spectral data confirmed the introduction of the BTh to the Cs backbone as well as the coupling between the two polymers. SEM data showed homogenous polymer surfaces with well-distributed Ag nanoparticles. The Ag contents in the prepared samples Cs2 and Cs3 were, respectively, 0.61 and 0.21%, however, TEM analysis showed that the sizes of AgNPs and Ag/TiO 2 NPs were in the range of 3–7 nm and 15–22 nm for the prepared conjugates, respectively. The antibacterial activity of the synthesized conjugates was investigated against two Gram-negative (E. coli , and S. typhimurium) and two Gram-positive (S. aureus , and L. monocytogenes) bacteria. The antibacterial assay showed that all three Cs-PVC (Cs1, Cs2, and Cs3) conjugates modified with BTh exhibited excellent bacterial inhibition after 30, 60, and 120 min. [ABSTRACT FROM AUTHOR]