Garcinia indica mediated biogenic synthesis of silver nanoparticles with antibacterial and antioxidant activities

This reports the optimization of various parameters for biogenic synthesis of Silver nanoparticles using fruit extract of Garcinia indica, popularly known as Kokum. For optimization, the effects of various parameters such as concentration of AgNO3, ratio of AgNO3 to extract, pH, incubation temperature and time were varied and studied for their effect on synthesis. 1.5 mM AgNO3, 1:1 ratio of AgNO3 to Kokum fruit extract, pH 10, incubation of reaction mixtures at 37 degrees C for 24 h were the optimum parameter for biogenic synthesis. The biogenic AgNPs were then characterized by UV-vis absorption spectroscopy, fourier transform infra-red (FT-IR) spectroscopy, field emission scanning electron microscope (FE-SEM) imaging, energy dispersive X-ray (EDS) spectrometer, X-ray powder diffractometer (XRD), transmission electron microscope (TEM) imaging and the selected area electron diffraction (SAED) pattern. The biogenic AgNPs alone and in combination with Tetracyclin showed antibacterial activity against the four of seven tested bacteria. In addition, biogenic AgNPs also demonstrated good antioxidant activities such as DPPH, hydrogen peroxide, nitric oxide (NO) radical scavenging and reducing power activities. This study demonstrates that Garcinia indica fruit extract can be used for biogenic production of AgNPs with potential antibacterial and antioxidant activities that can be exploited for commercial biomedical application. (C) 2018 Elsevier B.V. All rights reserved.