Biological synthesis of silver nanoparticles using Dracocephalum kotschyi extract and evaluation of its antibacterial activity

Nosocomial infections are one of the most common infections in health centers. The high and inadequate use of broad-spectrum antibiotics has increased the number of nosocomial infections. The aim of this study was to synthesized silver nanoparticles using Dracocephalum kotschyi extract and analysis of its antibacterial activities. In this experimental study, biological synthesis of silver nanoparticles was performed using D. kotschyi extract. Physical and chemical structure of synthesized silver nanoparticle were determined using UV-Vis spectroscopy, XED, FTIR, SEM (scanning electron microscopy) and transmission electron microscopy (TEM). Finally, the antibacterial activity of silver nanoparticles was assessed using two methods including disk diffusion and minimum growth inhibitory concentration (MIC). The results showed that the size of the synthesized nanoparticle was 14.57 nm. The physical and chemical structure of silver nanoparticles was confirmed by XRD, TEM, and SEM. The antibacterial results also showed that Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Listeria monocytogenes were sensitive to 500 μg/ml of silver nanoparticles. The results of this study showed that the silver nanoparticles synthesized by D. kotschyi have an appropriate antibacterial potential against nosocomial pathogens and can act as one of the nano-achievements in helping to management of infectious diseases.