Green synthesis of silver nanoparticles using Combretum erythrophyllum leaves and its antibacterial activities

A simple, green, cost effective and environmentally benign method for the synthesis of silver nanoparticles (Ag-NPs) using aqueous extract of Combretum erythrophyllum plant leaves as both the reducing and capping agents is herein reported for the first time. The as-prepared Ag-NPs were characterised using Ultraviolet-Visible (UV-Vis) absorption spectroscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and dynamic light scattering (DLS) techniques. TEM image showed that the particles are spherical in shape, and well dispersed with the average particle diameter of 13.62 nm. The as-synthesised Ag-NPs showed efficient antibacterial activities against pathogenic Gram- positive Staphylococcus aureus (ATCC 25923) & Staphylococcus epidermidis (ATCC 12228), and Gram-negative Escherichia coli (ATCC 10536) & Proteus vulgaris (33420). Compared to the streptomycin drug, which was ineffective against S. epidermidis, the as-synthesised Ag-NPs were effective against S. epidermidis and other Staphylococcus species that are implicated in different dermatological infections.