Antibacterial activities of silver nanoparticles synthesized using aqueous extract of ginger (Zingiber officinale) rhizome

Abstract

This study aimed to synthesize silver nanoparticles (AgNPs) from aqueous extract of ginger rhizome using AgNO3 as precursor and to evaluate antibacterial activities of the synthesized AgNPs against some clinical bacterial isolates and bloom forming cyanobacterial strain. The synthesis was carried out by mixing 1mM silver nitrate solution with aqueous extract of ginger rhizomes (10:1). The synthesized AgNPs were characterized by UV-visible spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The AgNPs were dark brown in color and have maximum absorbance at 429 nm. FTIR spectrum showed strong and distinct peak at 3356, 2855, 2129, and 1636 cm-1, indicating the role of biomolecules in the capping and stabilization of the particles. They have spherical shape with size ranging from 30-90 nm. The particles demonstrated potent antibacterial activities against clinical isolates of Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli and bloom forming cyanobacterial strain. This study therefore, suggests the application of the synthesized AgNPs in the manufacture of antibacterial drug and as anticyanobacterial agent in freshwater treatment.