Green biosynthesis, characterisation and antimicrobial activities of silver nanoparticles using fruit extract of <i>Solanum viarum</i>

Abstract

Green synthesis of nanoparticles is considered an efficient method when compared with chemical and physical methods because of its bulk production, eco-friendliness and low cost norms. The present study reports, for the first time, green synthesis of silver nanoparticles (AgNPs) at room temperature using <i>Solanum viarum</i> fruit extract. The visual appearance of brownish colour with an absorption band at 450 nm, as detected by ultraviolet-visible spectrophotometer analysis, confirmed the formation of AgNPs. X-ray diffraction confirmed the AgNPs to be crystalline with a face-centred lattice. The transmission electron microscopy-energy dispersive X-ray spectroscopy image showed the AgNPs are poly-dispersed and are mostly spherical and oval in shape with particle size ranging from 2 to 40 nm. Furthermore, Fourier transform-infrared spectra of the synthesised AgNPs confirmed the presence of phytoconstituents as a capping agent. The antimicrobial activity study showed that the AgNPs exhibited high microbial activity against <i>Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus</i> susp. <i>aureus</i>, <i>Aspergillus niger,</i> and <i>Candida albicans</i>. The highest antimicrobial activity of AgNPs synthesised by <i>S. viarum</i> fruit extract was observed in <i>P. aeruginosa</i>, <i>S. aureus</i> susp. <i>aureus</i> and <i>C. albicans</i> with zone of inhibition, 26.67 mm.