Title : Efficacy of copper-loaded carbon nanoparticles against Listeria monocytogenes isolated from canned food
Abstract:
L. monocytogenes, a major foodborne pathogen, poses significant health risks in canned foods and processed products. The emergence of multidrug-resistant strains and their persistence in food processing environments have necessitated the search for alternative antimicrobial agents. CNPs and CuNPs are known for their strong antibacterial properties due to their high surface area, reactivity, and ability to disrupt microbial membranes. When combined, these nanoparticles may offer enhanced antibacterial activity, leveraging the synergistic effects of both particles.
Objective: The study aimed to evaluate the antimicrobial efficacy of Cu-CNPs against L. monocytogenes which is a foodborne pathogen gram positive bacterium able to cause listeriosis. This study also examined the protein-ligand interaction of LLO, a critical virulence protein of L. monocytogenes, through in silico docking to elucidate the mechanism behind their antimicrobial action.
Methodology: L. monocytogenes isolates were obtained from canned food and domestic shop samples. CuNPs and CNPs were synthesized by chemical methods and their characterization was done using techniques such as FTIR, DLS, UV spectrometry and XRD to determine their morphology.
Result: The antagonistic activity of CuNPs, CNPs and Cu-CNPs were evaluated against Listeria monocytogenes using well diffusion method. CNPs and Cu-CNPs demonstrated significant antibacterial activity and showed efficacy against L. moncytogenes showed antagonistic effect in all isolates, while CuNPs showed antagonistic effect in 8 out of 20 isolates and had less efficacy in inhibiting bacterial growth. In silico analysis also showed good binding energies when LLO interacted with the ligands.
Conclusion:Hence, this study indicates that copper loaded carbon nanoparticles showed synergistic effect in combination and proved to be good alternative in the treatment of L. monocytogenes.
Keywords: Carbon nanoparticles(CNPs), Copper nanoparticles (CuNPs), Copper loaded carbon nanoparticles (Cu-CNPs), Listeriolysin O (LLO).
