OICC Press Journal of Nanostructure in Chemistry 2193-8865 11 2 (June 2021) 2020 11 12 Biogenic zinc oxide, copper oxide and selenium nanoparticles: preparation, characterization and their anti-bacterial activity against Vibrio parahaemolyticus 10.1007/s40097-020-00365-7 EN D Vinu Centre for Ocean Research (DST-FIST Sponsored Centre), MoES-Earth Science and Technology Cell, Sathyabama Institute of Science and Technology, Chennai, 600 119, IN K. Govindaraju Centre for Ocean Research (DST-FIST Sponsored Centre), MoES-Earth Science and Technology Cell, Sathyabama Institute of Science and Technology, Chennai, 600 119, IN R. Vasantharaja Centre for Ocean Research (DST-FIST Sponsored Centre), MoES-Earth Science and Technology Cell, Sathyabama Institute of Science and Technology, Chennai, 600 119, IN S. Amreen Nisa Centre for Ocean Research (DST-FIST Sponsored Centre), MoES-Earth Science and Technology Cell, Sathyabama Institute of Science and Technology, Chennai, 600 119, IN M. Kannan Department of Nano Science and Technology, Tamil Nadu Agricultural University, Coimbatore, 641 003, IN K. Vijai Anand Department of Physics, Sathyabama Institute of Science and Technology, Chennai, 600 119, IN Journal Article 2020 11 12 Abstract The present study investigates biogenic preparation of zinc oxide (ZnO), copper oxide (CuO) and selenium (Se) nanoparticles using the marine brown alga Sargassum swartzii. The prepared nanomaterials were characterized using X-ray diffraction pattern (XRD), scanning electron microscopy (SEM) equipped with energy dispersive X-ray analysis (EDAX), transmission electron microscopy (TEM) and UV–Vis diffuse reflectance spectroscopy (DRS-UV) analysis. The particle size of biogenic ZnO, CuO and Se nanoparticles was ca. 32, 32 and 21 nm, respectively. The isolation of bacterial pathogenic strain Vibrio parahaemolyticus ( V. parahaemolyticus ) from the diseased shrimp and virulent genes ( toxR and tlh ) confirmed by PCR technique. Further, the molecular characterized using 16S ribosomal RNA gene sequences and identified new strain V. parahaemolyticus strain (GRCORNICRA001). Anti-bacterial activity of biogenic nanomaterials (ZnO, CuO and Se) was investigated against isolated V. parahaemolyticus using well diffusion method and growth inhibitory assay. The minimum inhibitory concentration (MIC) was 25, 25 and 10 µg mL −1 of ZnO, CuO and Se nanoparticles, respectively. The results show that there is a strong bacterial inhibition in a dose-dependent manner. Further, SEM analysis revealed that the interaction of nanomaterials with V. parahaemolyticus, resulted in a surface tension change that leads to membrane depolarization, formation of abnormal textures such as membrane rupture, membrane blebs, membrane clumping, and also caused cell death. Results of this effort highlighted the way for the future that these nanomaterials incorporated with shrimp feed for the management of aquatic diseases. Graphic abstract