Silver nanoparticles synthesised by using Iranian Mentha pulegium leaf extract as a non-cytotoxic antibacterial agent

ABSTRACT

Silver nanoparticles (AgNPs) were biosynthesized using the aqueous extract ofMentha  pulegium leaves and were characterized by Ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, Scanning electron microscopy, X-ray diffraction, Energy-dispersive X-ray spectroscopy, and X-ray fluorescence analysis. The bactericidal activity was assayed by disc diffusion and broth microdilution methods. The cytotoxicity was examined on normal human peripheral blood mononuclear cells (PBMCs) by MTT assay. SEM and XRD analysis showed the spherical and face-centered cubic nano silver particles with an average size of 29 nm. EDX and XRF spectra exhibited obvious signals in the silver region. The AgNPs displayed antibacterial activity against Staphylococcus aureus followed by Bacillus cereus, Klebsiella pneumoniae and Escherichia coli with minimum inhibitory concentrations (MICs) ranged from 61.5 to 125 µg/mL. No significant cytotoxicity was observed against the PBMCs up to 250 μg/mL of the AgNPs and hence the synthesized AgNPs may be used to treat drug-resistant bacteria in biomedicine.

KEYWORDS:

• Mentha pulegium aqueous extract
• green synthesis
• biosafety
• antibacterial
• ag nanoparticles
• drug-resistant

Acknowledgments

The authors wish to thank Prof. Mahendra Rai for his critical editing of the manuscript. This study was financially supported by the Research Deputy of Lorestan University, Iran.

Disclosure statement

No potential conflict of interest was reported by the authors.