GREEN SYNTHESIS OF SILVER NANOPARTICLES BY EXTRACT OF JUGLANS REGIA LEAF AND EVALUATION OF ITS ANTIBACTERIAL EFFECTS

Background and Aim:The biological approaches to synthesis of nanoparticles are better than chemical and physical procedures because of low energy and time expenditure. Green synthesis of nanoparticles is an eco-friendly method and uses natural solvent. The aim of this study is to biosynthesis of silver nanoparticles and to evaluate its antibacterial activityMethods:In this experimental study AgNPs were prepared by the reaction of 1mM silver nitrate and extracts of juglans regia lesf . Antibacterial activity of AgNPs was assessed by using disc diffusion method against Staphylococcus aureus PTCC 1431, Bacillus cereus 1015 PTCC and Escherichia coli PTCC 1399, Pseudomonas aeruginosa PTCC 1571 and Acinetobacter baumannii PTCC 1855 . The AgNPs were characterized by UV-visible (vis) spectrophotometer, particle size analyzer by dynamic light scattering (DLS) method, and SEM techniques.Results:In this study, . Antibacterial activity was observed against all tested bacteria , so that most antibacterial effect observed on P.aeroginosa and A.baumannii and the lowest effect was observed on E. coli . The formation of silver nanoparticles was confirmed by the presence of an absorption peak at 450 nm using spectrophotometer, The SEM showed AgNPs was spherical shape of size ranging from 33 to 45 nm . and a zeta potential of -19.6 mV was recorded,indicating a very good stability of nanoparticles.Conclusion:results showed biological nanoparticles of Ag and extract of juglans regia leaf as well as AgNO3 have antimicrobial properties against pathogenic bacteria ,but the most antimicrobial effects were observed by Ag NPs.

Keywords:

Anti-Bacterial Activity , Green synthesis , Nanoparticle , Silver