CHARACTERIZATION AND BIOLOGICAL EVALUATION OF SILVER NANOPARTICLES SYNTHESIZED BY AQUEOUS ROOT EXTRACT OF DESMODIUM GANGETICUM FOR ITS ANTIOXIDANT, ANTIMICROBIAL AND CYTOTOXICITY

Obective: To evaluate the biological significance of silver nanoparticles synthesized by aqueous root of Desmodium gangeticum and to understand its antioxidant, antimicrobial and cytotoxic activity. Methods: In the present study silver nanoparticles (AgNPs) were synthesized with precursor silver nitrate using aqueous root extract of Desmodium gangeticum (DG). Chemical synthesis of AgNPs was done by following the procedure by Guzman et. al (2009) with little modification. The AgNPs were further characterized by different techniques like UV-visible Spectrometer, X-ray Diffraction (XRD), Fourier Transform Infra-Red spectroscopy (FTIR), Scanning electron microscopy (SEM) and Thermo Gravimetric Analysis (TGA). Results: The presence of silver nanoparticles with an average size between 30-40 nm and exhibiting face centred cubic structure was confirmed. SEM reveals the morphology of the nanoparticles as spherical and the IR spectra confirms the presence of phyto-constituents in AgNPs that not only acts as reducing agent, but also stabilize the particles. Biological evaluation of the nanoparticles showed significant antimicrobial and antioxidant activity. AgNPs possess relatively low cytotoxicity to LLC-PK1 cells compared to DG extract and the precursor silver nitrate. Conclusion : Biological evaluation of the nanoparticles showed significant antimicrobial and antioxidant activity. AgNPs possess relatively low cytotoxicity to LLC-PK1 cells compared to DG extract and the precursor silver nitrate. Compared to physical and chemical method of nanoparticle synthesis, biological procedure is ecofriendly and cost effective.