Antimicrobial activity of green synthesized silver and copper oxide nanoparticles against the foodborne pathogen Campylobacter jejuni

Authors: RIVERA-MENDOZA, DANIEL - Centro De Investigacion Cientifica Y De Educacion Superior De Ensenada; Quinones, Beatriz; HUERTA-SAQUERO, ALEJANDRO - Centro De Investigacion Cientifica Y De Educacion Superior De Ensenada; CASTRO-LONGORIA, ERNESTINA - Centro De Investigacion Cientifica Y De Educacion Superior De Ensenada

Submitted to: Antibiotics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/10/2024
Publication Date: 7/14/2024
Citation: Rivera-Mendoza, D., Quinones, B., Huerta-Saquero, A., Castro-Longoria, E. 2024. Antimicrobial activity of green synthesized silver and copper oxide nanoparticles against the foodborne pathogen Campylobacter jejuni. Antibiotics. 13(7). Article 650. https://doi.org/10.3390/antibiotics13070650.
DOI: https://doi.org/10.3390/antibiotics13070650

Interpretive Summary: Nanotechnology provides many applications across diverse sectors like medicine, agriculture, and environmental remediation. For the synthesis of nanoparticles, green chemistry has emerged as a focal point, drawing interest for their eco-friendly and sustainable characteristics. In particular, the use of ‘bio-factories’ such as fungi represents novel approaches since these methods are more cost-effective and environmentally benign. To develop alternative antimicrobial strategies for food safety, the present study is the first report documenting the use of green chemistry for the novel synthesis of metallic nanoparticles, derived from the wood decay fungus Ganoderma sessile, for inhibiting Campylobacter jejuni, a major cause of global foodborne illnesses. The biosynthesized silver and copper oxide nanoparticles effectively and specifically interacted with C. jejuni and inhibited the growth of this human pathogen at low concentrations.

Technical Abstract: Campylobacter jejuni is a major cause of global foodborne illnesses. To develop alternative antimicrobial strategies against C. jejuni, this study designed and optimized the green synthesis of metallic nanoparticles (NPs) with intracellular components of the medicinal fungus Ganoderma sessile to provide the needed reducing and stabilizing agents. By employing transmission electron microscopy and dynamic light scattering, the quasi-spherical NPs had sizes of 2.9 ± 0.9 nm for the copper oxide NPs and 14.7 ± 0.6 nm for the silver NPs. Surface charge assessment revealed zeta potentials of -21.0 ± 6.5 mV and -24.4 ± 7.9 mV for the copper oxide and silver NPs, respectively, and the negative surface charge indicated that the synthetized particles were electrically stabilized without aggregation. The growth inhibition of C. jejuni by the NPs occurred through attachment to the outer cell membrane and subsequent intracellular internalization and resulted in minimal inhibitory concentrations of the silver NPs at 6 µg/ml and copper oxide NPs at 10 µg/ml. In summary, this research presented the first demonstration of using green synthesis with the medicinal fungus G. sessile to produce metallic NPs that effectively inhibited C. jejuni growth, providing a sustainable and effective approach to the traditional use of antimicrobials.