Synthesis and Characterization of Metal Nanoparticles using Catharanthus roseus Grown Under Various Physiological Conditions with Special Reference to their Antimicrobial Activities

Abstract

Nanotechnology is the fusion of material science, chemistry, physics, and engineering sciences to develop useful structures and tools which at least possess a nano-metrical dimension in the size of 1 to 100 nm (10-9 m). The present study is an attempt to develop a laboratory procedure for the biosynthesis of nanoparticles from C. roseus under controlled conditions. In the initial stage, plant samples were collected and extracts prepared for the reduction of Ag and ZnO to synthesize nanoparticles. Leaves explants were surface sterilized by HgCl2 and 70% alcohol with sterile distilled water and grown on MS media which is containing 1mg NAA+ 3mg BAP (pH 5.7) under in-vitro condition. The cultures were maintained at 25±10C under different photoperiods (16/8 hours light and dark, control; 16/8h dark/light, short days; and 20/4h light/dark, long days). The best callus formation and pigmentations were reported at pH 5.7 under control conditions. The callus extract of both nanoparticles (at pH 5.7) revealed the high potential antimicrobial activity of synthesized metal nanoparticles against microbes as compared to the leaves extract. The synthesized (Ag and ZnO) nanoparticles using leaves and callus extract were characterized using various techniques viz. UV-Visible analysis, XRD, FTIR, DLS, AFM, SEM, EDX, and TEM. These techniques determine the size (lt100nm), shape, purity, phase composition, presence of different functional groups and metal composition of the synthesized nanoparticles. newlineIn conclusion, the study offered the potential methods to synthesize nanoparticles which can act as highly potential antimicrobial agents that are cost-effective, less time consuming and eco-friendly. The antibacterial activity of nanoparticles individually and in combination with existing antibiotics and natural products will encourage developing newer compounds and also providing a new route against multidrug resistant bacteria. newline newline