Biologically synthesized silver nanoparticles enhances antibiotic activity against Gram-negative bacteria

•We described a simple, reliable, cost effective and environmentally friendly method for synthesis of silver nanoparticles using biological systems.•Safe, non-toxic and from waste to green.•Biologically synthesized silver nanaoparticles show potential antibacterial activity.•Silver nanoparticles enhance antibacterial activity of antibiotics against Gram negative bacteria.

Here we report a simple, fast, cost-effective, and nonpolluting approach for synthesis of silver nanoparticles (AgNPs) using leaf extract of Typha angustifolia. We demonstrate the dose-dependent antibacterial activity of AgNPs and different antibiotics against Escherichia coli and Klebsiella pneumoniae. Furthermore, we demonstrate the efficacy of AgNPs in combination with various broad-spectrum antibiotics against E. coli and K. pneumoniae. The results show that combinations of antibiotics and AgNPs show significant antimicrobial effects at sub-lethal concentrations of the antibiotics. These data suggest that combinations of antibiotics and AgNPs can be used therapeutically for the treatment of infectious diseases.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide