Antibacterial activity of green gold and silver nanoparticles using ginger root extract

Abstract

BackgroundRecent studies demonstrated that the speed of synthesis, biocompatibility, and antimicrobial activity of gold (Au) and silver (Ag) metals is enhanced when biosynthesized in nano-sized particles. In the present study, Au NPs and Ag NPs were synthesized via a biological process using aqueous Ginger root extract and characterized by various spectroscopic methods. Methods & ResultsThe NPs were found to be in hexagonal and spherical shapes. The average particle size for Au and Ag NPs was found to be 20 nm and 15 nm, respectively. The dynamic light scattering (DLS) method has shown that the zeta potential values of synthesized NPs were found to be 5.7 mv and 7.11mv, respectively. Gas chromatography-mass spectrometry (GC-MS) analysis of Ginger root extract revealed 25 compounds. The synthesized NPs showed significant activity against Staphylococcus aureus and Escherichia coli in vitro with IC50 and IC90 values for Au and Ag NPs, respectively, noted to be 7.5 and 7.3 µg/ml and 15 and 15.2 µg/ml for both bacterial strains. The protein leakage level was high and morphological changes occurred in bacteria treated with biosynthesized NPs. ConclusionThese results suggest that the biosynthesized metallic NPs show potential for application as antibacterial agents with enhanced activities.