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Abstract Nanoparticles have gained worldwide attention as a new alternative to chemical control agents due to their special physiochemical properties. The current study focused on the environmentally friendly synthesis of silver nanoparticles (AgNPs) using Lycopersicon esculentum peel. In addition to studying the intrinsic cytotoxic effectiveness of Le-AgNPs contribute to their antibacterial, and antifungal activities and the effect of nanoparticles on the integrity of their morphological behavior. The initiative biosynthesis of L. esculentum silver nanoparticles (Le-AgNPs) was indicated by the color change of L. esculentum (Le) extract mixed with silver nitrate (AgNO3) solution from faint pink to faint brown. UV–visible spectroscopy, Dynamic light scattering (DLS), Fourier-transform infrared spectroscopy, high-resolution transmission electron microscopy (HR-TEM), and X-ray diffraction techniques were used to characterize biosynthesized Le-AgNPs. Results of UV–visible spectroscopy recorded surface plasmon resonance at 310 nm for SPR of 2.5. The DLS results showed particles of 186 nm with a polydispersity index of 0.573. The FTIR spectrum indicated the existence of carboxyl, hydroxyl, phenolic, and amide functional groups. The HR-TEM analysis revealed quasi-spherical crystal particles of Le-AgNPs. Le-AgNPs had a negative zeta potential of − 68.44 mV, indicating high stability. Bacillus subtilis ATCC 6633 and Escherichia coli ATCC 8739 were the most susceptible pathogens to Le-AgNPs inhibition, with inhibition zone diameters (IZDs) of 4.0 and 0.92 cm, respectively. However, Listeria monocytogenes NC 013768 and Shigella sonnei DSM 5570 were the most resistant pathogens, with IZDs of 0.92 and 0.90 cm, respectively. Le-AgNPs demonstrated good inhibitory potential against pathogenic fungi, with IZDs of 3.0 and 0.92 cm against Alternaria solani ATCC 62102 and Candida albicans DSM 1386, respectively. The cytotoxicity effect was observed at a half-maximal inhibitory concentration (IC50) of 200.53 μg/ml on human colon NCM460D normal cells.

Abstract Mosquitoes prefer stagnant areas near hospitals to live and easily spread pathogenic bacteria. Our current study aims to isolate multidrug-resistant (MDR) Staphylococcus aureus isolates from midguts of Mosquito Culex pipiens and study the potential of mint as a biocontrol strategy against C. pipiens larvae and their midgut-borne S. aureus. Samples of the third and fourth larval instars of C. pipiens were collected from water ponds around three Cairo hospitals. Ciprofloxacin, gentamycin and tetracycline, as well as various concentrations of mint leaf extract (MLE) were tested for antibiotic susceptibility. Sixty-five isolates were obtained and showed antibiotic resistance to tetracycline, gentamycin, ciprofloxacin, and undiluted MLE with resistant percentages (%) of 27.69, 30.76, 17.46, and 23.08%, respectively. Undiluted MLE inhibited 61.53% of the multidrug S. aureus isolates, whereas it couldn't inhibit any of these isolates at dilutions less than 50 μg/mL. The MIC of MLE was ≤ 700 µg/mL, while the MIC of the antibiotics ranged from 0.25 to 5.0 µg/mL for the three antibiotics. The most inhibited S. aureus isolate was identified by 16SrRNA sequencing approach and registered in GenBank as S. aureus MICBURN with gene accession number OQ766965. MLE killed all larval stages after 72 h of exposure, with mortality (%) reaching 93.33 and 100% causing external hair loss, breakage of the outer cuticle epithelial layer of the abdomen, and larvae shrinkage. Histopathology of treated larvae showed destruction of all midgut cells and organelles. Gas chromatography (GC) of MLE revealed that menthol extract (35.92%) was the largest active ingredient, followed by menthone (19.85%), D-Carvone (15.46%), Pulegone (5.0579%). Docking analysis confirmed that alpha guanine and cadinol had the highest binding affinity to both predicted active sites of Culex pipiens acetylcholinesterase. As a result, alpha-guanine and cadinol might have a role as acetylcholinesterase inhibitors.

Abstract 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 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.