Green Synthesis of Silver Nanoparticles Using Acacia cyanophylla and Its Antibacterial Activity

Abstract

Aims: The green synthesis of silver nanoparticles in an eco-friendly, economical and more effective approach using Acacia cyanophylla plant extract and study the effect of preparing conditions on the size of synthesis nanoparticles and its antibacterial activity. \n \nMethodology: In this study, we synthesis of silver nanoparticles by reduction method using aqueous silver nitrate solution and aqueous extract of Acacia cyanophylla. Then, studying their characterization by several methods, such as visual inspection, UV–Vis spectroscopy, and dynamic light scattering and scanning electron microscope and then study the effect of silver nitrate: extract ratio, type extract, temperature, reaction time on the size of prepared nanoparticles and also the antibacterial effect of these nanoparticles was studied on Escherichia coli using micro-dilution method and determination the Minimum Inhibitory Concentration (MIC). \n \nResults: The results showed that the silver nanoparticles prepared using Acacia cyanophylla extract have reported visible yellowish brown color formation and the absorption peak at 460 nm indicates the biosynthesis of silver nanoparticles and they have average diameter (88.11) nm and the polydispersity index (PdI) was suitable and the optimal conditions for synthesis silver nanoparticles were using aqueous extract in 9:1 ratio (silver nitrate: extract) at 35° C for 48 h and It is stable in the in the fridge at 5° C for a maximum period of 15 days. On the other hand, the antibacterial tests showed these nanoparticles have high antibacterial activity and the MIC value ranged between (3.125-12.5) μg/ml on E. coli isolates. \n \nConclusion: We conclude that Acacia cyanophylla extract has been considered effective reducing agent for preparation stable silver nanoparticles at certain conditions and this silver nanoparticle has a high antibacterial activity.