GREEN SYNTHESIS AND CHARACTERIZATIONS OF SILVER NANOPARTICLES USING FRESH LEAF EXTRACT OF MORINDA CITRIFOLIA AND ITS ANTI-MICROBIAL ACTIVITY STUDIES

摘要

Objective: To develop a rapid method of synthesis of silver nanoparticles (Ag NPs) using the fresh aqueous leaf extract of Morinda Citrifolia from 0.1 M AgNO 3 solution, to characterize the resulting Ag NPs and also compare their antimicrobial activity with those of standard drugs against human pathogenic bacteria. Methods: 25 ml of the aqueous extract was added to 25 ml of 0.1 M aqueous AgNO 3 at room temperature. The mixture was stirred continuously for 5-10 minutes. The reduction was completed with the appearance of brownish-black colored dispersion. The resulting nanoparticles were characterized using UV-Vis absorption spectra and Particle size analysis (DLS method). Further the Antimicrobial activity was compared with the drugs against S. aureus and P. aureginosa strains using the disk diffusion method. Results: The formation of Silver nanoparticles was confirmed with the help of UV-Vis absorption spectra at ≈ 425 nm and particle size as approximately 100 nm using Particle size analysis (DLS method). The anti-microbial activity of the Ag NPs so synthesized was studied against human pathogens in wound infections such as S. aureus and P. aureginosa strains. The inhibitory activity for Ag NPs was compared with those of known drugs such as tetracycline, Ceftazidime and Amikacin at 30 mcg. The inhibitory activity of the Synthesized Ag NPs was found pronounced against P. aureginosa strains. Conclusion: A rapid method of synthesizing Ag NPs has been developed by using the fresh leaf extract of Morinda Citrifolia and it was found that the extract is a potential reducing agent to produce stable Ag NPs. The research provides a new input to the development of anti-microbial agent. Keywords: Nanomaterial, Green synthesis, Silver nanoparticles, Morinda Citrifolia , Anti microbial activity.