ABSTRACT
A novel synthesis of MgO/ZnO nanocomposite using a template, namely an eggshell membrane (ESM) was attempted. The nanocomposite was characterized by XRD, UV-visible, FTIR, Raman, DLS (zeta potential and particle size distribution), FESEM with EDX, and HRTEM analysis. The presence of periclase cubic MgO (space group Fm3m) and hexagonal wurtzite ZnO (space group P63mc) structures was verified by the XRD results. The average crystallite size of the MgO/ZnO nanocomposite was equal to 9.43 nm. The nanocomposite exhibited an on-set of absorbance close to 300 nm. From the taucs plot, the bandgap of the composite was calculated, and it was equal to 3.63 eV. The FTIR spectrum of the composite showed Mg-O stretching vibration at 455 cm-1 and that of Zn-O at 564 cm-1. The zeta potential and the particle size distribution of the nanocomposite were equal to - 35.5 mV and 176.1 nm. The FESEM images of the nanocomposite appeared as an aggregated honeycomb with a cubic and hexagonal structure. The EDX analysis showed the presence of Mg (23.65 atom%), Zn (27.95 atom%), and O (48.40 atom%). The antibacterial and antifungal activities of the nanocomposite were investigated using the agar-well diffusion method. The antibacterial activity exhibited the highest zone of inhibition for Bacillus subtilis (25 ± 0.41 mm) and Shigella dysenteria (25 ± 0.19 mm), whereas the antifungal activity showed the highest zone of inhibition for Aspergillus terrus (27 ± 0.25 mm). The MIC value of the nanocomposite was equal to 9.37 (µg/mL) for all the bacteria. Hence, it is verified that the present MgO/ZnO nanocomposite could very well be used to treat bacterial and fungal infections.
Subject(s)
Zinc Oxide , Animals , Zinc Oxide/pharmacology , Zinc Oxide/chemistry , Antifungal Agents/pharmacology , Magnesium Oxide , Egg Shell , Bacteria , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistryABSTRACT
Groundnut (Arachis hypogaea L.) plants showing distinct symptoms of necrosis of leaves and severe rotting of roots were observed in an agricultural field at Arakkonam, Tamil Nadu, India. The rhizomorphs of the phytopathogenic fungus were obtained from the rotted roots of the diseased plants and were cultured in the laboratory, and based on the morphological characteristics and nucleotide sequencing analysis of ITS and nLSU region, the phytopathogen was identified as Marasmius palmivorus. The isolated fungus produced distinct fruiting bodies (basidiocarps) when grown under the laboratory conditions. The fungus grew as cottony white colonies on the potato dextrose agar medium and were found to contain septate and clamp connections when examined under light microscope. The pathogenicity of the isolated fungus was assessed by inoculating it on healthy groundnut plant under glasshouse conditions; this resulted in the establishment of typical disease symptoms, which confirmed the pathogenicity of the fungus. The fungal pathogen re-isolated from the artificially inoculated plants was used for molecular characterization and confirmed that the organism was M. palmivorus. To the best of our knowledge, this is the first report on the occurrence of M. palmivorus, causing white root rot disease in A. hypogaea L.
Subject(s)
Arachis , Marasmius , IndiaABSTRACT
Silver nanoparticles (Ag NPs) were synthesized by a simple microwave irradiation method using polyvinyl pyrrolidone (PVP) as a capping agent and serine as a reducing agent. UV-Visible spectra were used to confirm the formation of Ag NPs by observing the surface plasmon resonance (SPR) band at 443nm. The emission spectrum of Ag NPs showed an emission band at 484nm. In the presence of microwave radiation, serine acts as a reducing agent, which was confirmed by Fourier transformed infrared (FT-IR) spectrum. High-resolution transmission electron microscopy (HR-TEM) and high-resolution scanning electron microscopy (HR-SEM) were used to investigate the morphology of the synthesized sample. These images showed the sphere-like morphology. The elemental composition of the sample was determined by the energy dispersive X-ray analysis (EDX). Selected area electron diffraction (SAED) was used to find the crystalline nature of the Ag NPs. The electrochemical behavior of the synthesized Ag NPs was analyzed by the cyclic voltammetry (CV). Antibacterial experiments showed that the prepared Ag NPs showed relatively similar antibacterial activities, when compared with AgNO3 against Gram-positive and Gram-negative bacteria.
Subject(s)
Anti-Bacterial Agents/chemistry , Metal Nanoparticles/chemistry , Serine/chemistry , Silver Compounds/chemistry , Silver/chemistry , Anti-Bacterial Agents/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Microscopy, Electron, Scanning/methods , Microscopy, Electron, Transmission/methods , Particle Size , Silver/pharmacology , Silver Compounds/pharmacology , Spectrometry, X-Ray Emission/methods , Spectrophotometry, Ultraviolet/methods , Spectroscopy, Fourier Transform Infrared/methods , X-Ray Diffraction/methodsABSTRACT
Environment pollution is simply a consequence of the anthropogenic activities of mankind. Emissions from the motor vehicles have been shown to be the major contribution to air pollution in the urban environment. The major pollutants are SO2, No(x) and CO. Of these pollutants carbon monoxide is of utmost importance as the pollutant has serious toxicological effects and proves fatal on mankind. In this study, the concentration of Carbon-Monoxide (CO) along and near the major roads at Coimbatore west zone due to vehicular emission is predicted using the Air Quality Modelling Software Called CALINE4 model. Using MAPINFO GIS environment, thematic maps of the CO pollution at different receptor heights were prepared. Also, the concentration of CO for the year 2004 at 1.8 m height and 5 m height were predicted. In addition, to create awareness about the air quality, suggestions had been given to take suitable measures from engineering and environmental point of view.
