Biosynthesis of silver nanoparticles using fresh extracts of <i>Tridax procumbens</i> Linn

359-368<span style="mso-bidi-font-size: 9.0pt;letter-spacing:-.1pt" lang="EN-GB">A simple and eco-friendly method for the synthesis of biogenic nanoparticles (NP’s) using an aqueous solution of <span style="mso-bidi-font-size:9.0pt;letter-spacing: -.1pt" lang="EN-GB">T. procumbens <span style="mso-bidi-font-size: 9.0pt;letter-spacing:-.1pt;font-style:normal" lang="EN-GB">fresh <span style="mso-bidi-font-size:9.0pt;letter-spacing: -.1pt" lang="EN-GB">plant extract (leaf and stem) as a bioreductant is reported. The prepared biogenic nanoparticles were well characterized using U.V. visible spectroscopy, scanning electron microscopy, X-ray diffraction and Fourier-transform infrared spectroscopy. The particles were confirmed to be elemental crystal by X-ray diffraction. <span style="mso-bidi-font-size:9.0pt;letter-spacing: -.1pt" lang="EN-GB">The <span style="mso-bidi-font-size:9.0pt; letter-spacing:-.1pt" lang="EN-GB">potential applications of biosynthesized nanoparticles as antimicrobial (antibacterial and antifungal) against pathogens Escherichia coli, Vibrio cholerae, Aspergillus niger and Aspergillus flavus were demonstrated. </span

<span style="font-size:11.0pt;font-family: "Times New Roman";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;mso-ansi-language:EN-GB;mso-fareast-language:EN-US;mso-bidi-language: HI" lang="EN-GB">Assessment of antibacterial and antifungal activities of silver nanoparticles obtained from the callus extracts (stem and leaf) of <i>Tridax procumbens</i> L.</span>

114-120Now-a-days metal nanoparticles are potentially used as tools in the field of engineering and biological sciences as well as in industries and communication technologies. The important aspect of nanotechnology is to develop dependable, environmentally benign processes for the synthesis of nanoscale materials. Presently, we describe a cost-effective and eco-friendly technique for green synthesis of biogenic nanoparticles from the extract of callus obtained through stem and leaves of Tridax procumbens L., which acted as a reducing as well as capping agent. This plant has been opted for the present study for its known medicinal properties. This method of synthesizing nanoparticles led to rapid reduction of silver ions, resulting in the formation of stable crystalline nanoparticles in the solution. The synthesis of biogenic nanoparticles was carried out by adding silver nitrate solution to the callus extract. Nanoparticles were screened using UV-Visible absorption spectroscopy and were well characterized by SEM, XRD and FTIR analysis. The process responsible for the formation of nanoparticles from the biomass of plant callus is called bio-mineralization. The synthesized biogenic nanoparticles were further tested for antimicrobial activity using Escherichia coli, Vibrio cholerae, Aspergillus niger and A. flavus. Later, the activities of synthesized biogenic nanoparticles were also compared with various plant extracts (aqueous, ethanolic and methanolic) of T. procumbens