Author(s): Azharuddin Daphedar and Tarikere C Taranath*
Green synthesis of nanoparticles and their diverse applications are grown in various fields of nanoscience. In the present investigation, genotoxic effect of biogenic zinc nanoparticles on the root tip chromosomes of Drimia polyantha was evaluated. Biogenic zinc nanoparticles were characterized by UV-visible, XRD, FT-IR, AFM and HR-TEM analysis. The UV spectrum shows characteristic absorption peak at 374 nm. FTIR data suggested involvement of different functional groups in leaf extract were responsible for the reduction, capping and stabilization of ZnNPs. XRD results confirmed the crystalline nature of zinc nanoparticles with face centered cubic structure. AFM and HR-TEM images reveal the size and shape of nanoparticles. The size of ZnNPs ranges between 5 to 80 nm and are spherical in nature. The effect of zinc nanoparticles on mitotic index (MI) and the chromosomal aberrations (CAs) was determined by the exposing root meristimetic cells of D. polyantha to different concentrations viz. 4, 8, 12 and 16 μg/ml of zinc nanoparticles suspension at the interval of 6, 12, 18 and 24 hrs. The investigation, revealed that the significant decrease (19.43±1.58) in mitotic index and increase in chromosomal aberrations (36.09±3.29), dose and duration dependent, when compared to control. The treated meristimetic cells showed various types of chromosomal abnormalities including bridges, sticky, laggard, diagonal, Cmetaphase, multipolar anaphase, disturbed metaphase and micronucleus.