CALLUS MEDIATED BIOSYNTHESIS OF ZINC OXIDE NANOPARTICLES USING?CATHARANTHUS ROSEUS?GROWN UNDER VARIOUS PHYSIOLOGICAL CONDITIONS & THEIR CHARACTERIZATION: A NOVEL APPROACH TO DEVELOP POTENT ANTIMICROBIAL DRUG

摘要

The current research work is an attempt to develop a common laboratory procedure for synthesis of nanoparticles from C.roseus under controlled conditions.C.roseus, an important medicinal plant, has numerous secondary metabolites which act as reducing and capping agents through which size of nanoparticles can be regulated.Regulating size and morphology of nanoparticles under in-vitro conditions has been less focused and challenging.The present work also focuses to develop greener, highly feasible, rapid and cost-efficient methods to produce nanoparticles.The callus culture was exposed to altering photoperiods (16/8 hours light and dark: controlled, 16/8 hours dark/light: short days, 20/4 hours light/dark: long days).In another experiment, pH was also changed and callus was maintained at pH 5.0, 6.5, 7.0 under control light conditions.The callus was collected to reduce ZnO and form ZnO NPs.It was found that the best callus with optimum pigmentations was formed at pH 5.7 and under control light conditions.ZnO NPs synthesized from this callus demonstrated highest antibacterial activity against six different microbes.Moreover, these ZnO NPs were thoroughly characterized using various techniques viz.UV-Visible analysis, FTIR, XRD, SEM, TEM, EDX, AFM and DLS to determine morphology, size, presence of functional groups and dispersity.This research work provides the most recent and innovative technique for the development of nanoparticles through callus under controlled conditions thereby producing accurate-sized nanoparticles which increases their antimicrobial potency significantly.