Green synthesis of nano-silver and its antibacterial activity against methicillin-resistant Staphylococcus aureus

Abstract

Superbugs resistant to antimicrobials are swiftly expanding worldwide. One of these superbugs for which effective antibiotics are urgently needed is methicillin-resistant Staphylococcus aureus (MRSA). Thus, the creation of novel antimicrobial substances is necessary, one of the appealing antibacterial inorganic materials is silver nanoparticles (AgNPs) for application of treating bacterial infectious illnesses. In order to investigate novel, potent, and economically feasible therapeutic approaches, the current study presents a cost-effective and environmentally friendly technique for synthesizing AgNPs using Citrus maxima peel (CMP) extract as a reducing agent. UV–Vis Spectroscopy confirmed the formation of AgNPs in the 400–––500 nm wavelength range. The Powder X-ray diffr action (PXRD) and high-resolution transmission electron microscopy (HRTEM) results at the optimized synthesis conditions revealed highly crystalline AgNPs (face-centered cubic structure) with particles the size of 10–––20 nm. The Fourier transform infrared spectroscopy (FT-IR) revealed the presence of flavonoids, terpenoids, phenolics, and glycosides in the phytochemical compositions of the CMP extract, which can serve as reducing agents for the formation of the spherical AgNPs. Minimum inhibitory concentration (MIC) values of 8.27 µg/mL, minimum bactericidal concentration (MBC) values of 16.54 µg/mL, and an inhibition zone of 11.7 mm were indicative of the potent antibacterial activity of as-prepared AgNPs against MRSA. The findings suggest biogenic silver nanoparticles could be an effective antimicrobial agent against nosocomial infections.

Keywords

• Silver nanoparticles
• Sunlight irradiation
• Antibacterial
• Citrus maxima peel