Green synthesis of silver nanoparticles using the plant extracts of vitex agnus castus L: An ecofriendly approach to overcome antibiotic resistance

Background: These days, silver nanoparticles (Ag NPs) have been given considerable attention and applied in medical technology due to their great antimicrobial and antioxidant features. In the present study, we aimed to synthesize Ag NPs through the reduction of silver nitrate in the presence of Vitex agnus castus L fruit extract. Methods: After collecting fruits, their extract was prepared and added to Ag NO3 to produce Ag NPs. The effect of different parameters like AgNO3 concentration (0.5, 1, 3, and 5 mM), sunlight exposure, and sunlight irradiation time (10, 20, 30, and 40 min) was investigated in the synthesis of Ag NPs. The features of Ag NPs were characterized using UV-visible spectroscopy, scanning electron microscope (SEM), X-ray diffraction (XRD) analysis, and dynamic light scattering analysis. Moreover, antimicrobial function of Ag NPs was evaluated using Escherichia coli and Bacillus cereus bacteria species and minimal inhibitory concentration (MIC) of Ag NPs against these two pathogens was measured. Results: The results showed that the synthesized nanoparticles had a spherical shape and the range size of 30-60 nm. For the first time, the antimicrobial activity of synthesized Ag NPs of Vitex agnus castus L fruit extract was shown. Conclusions: It can be stated that the biosynthesis of Ag NPs using fruit extract of this plant is an environmentally friendly, economic and harmless method without any use of poisonous substances and no side effects. These Ag NPs can be considered as suitable antibacterial agents and replacements for antibiotics.