Green synthesis, characterization and antibacterial activity of silver nanoparticles from root extract of Lepidium draba weed

In the present study, Lepidium draba root was used to fabricate silver nanoparticles (Ag NPs). The NPs produced with different amounts of this weed root extract were analyzed by Fourier transform-IR spectroscopy. X-ray diffraction analysis and FE-SEM and TEM techniques were also used to morphologically investigate the particles' crystal structure. Staphyloccocus aureus, Bacillus cereus, Salmonella typhimurium, and Escherichia coli were then utilized to evaluate the antibacterial activity of the Ag NPs. SEM showed the formation of Ag NPs dispersed within the size range of 20-80 nm. X-ray diffraction analysis showed that the average crystalline size of synthesized Ag NPs was 24 nm. The results indicated that by increasing the concentrations of the root extract of L. draba, one can obtain smaller sized Ag NPs. The antimicrobial activity of those Ag NPs that had undergone green synthesis was more effective than that of corresponding silver ions.