Green synthesis of silver nanoparticles using aqueous extract of Froripia subpinnata and evaluation of their antibacterial activity

Biosynthesis of silver nanoparticles (Ag-NPs) has been achieved by a simple green chemical procedure using flavonoid-rich extract of Froripia subpinnata as a reducing agent and a capping agent. The successful formation of Ag-NPs was confirmed by ultraviolet-visible (UV-vis) spectrometer, field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy, and X-ray diffraction (XRD). FE-SEM and XRD studies showed that the formed silver nanoparticles were spherical in shape with an average particle size of similar to 30 nm, crystalline in nature. The effects of Froripia subpinnata extract (FSE) amount, concentration of AgNO3 and temperature were investigated on the synthesis of Ag-NPs. Furthermore, the Ag-NPs exhibited good antibacterial activity against Bacillus subtilis and Staphylococcus aureus (Gram-positive bacteria), Escherichia coli, and Pseudomonas aeruginosa (Gram-negative bacteria). Among the bacteria tested, Bacillus subtilis was found to be most susceptible to the silver nanoparticles.