Plant pathogenic fungus F. solanimediated biosynthesis of nanoceria: antibacterial and antibiofilm activity

• Published in: RSC advances Vol. 6; no. 48; pp. 42720 - 42729
• Main Authors: Venkatesh, K S, Gopinath, K, Palani, N S, Arumugam, A, Jose, Sujin P, Bahadur, SAsath, Ilangovan, R
• Format: Journal Article
• Language: English
• Published: 01.04.2016
• Subjects: Antibacterial properties; Bacteria; Escherichia; Formations; Infrared spectroscopy; Klebsiella pneumoniae; Nanoparticles; Nanostructure; Plants (organisms); Staphylococcus aureus; Transmission electron microscopy
• ISSN: 2046-2069
• DOI: 10.1039/c6ra05003d

The aim of the present study was to synthesize CeO sub(2) nanoparticles using plant pathogenic fungus F. solaniand also to study the antibacterial activity as well as the influence on the inhibition of biofilm formation against biomedically important bacterial strains namely Staphylococcus aureus, Psedomonas aeriginosa, Escherichia coliand Klebsiella pneumoniae. Thermogravimetric/differential thermal analysis (TG/DTA) suggested a crystallization temperature of the as-synthesized CeO sub(2) nanopowder at 400 degree C. Powder X-ray diffraction analysis and Raman spectroscopy substantiated the presence of CeO sub(2) nanoparticles with a cubic fluorite structure. The contribution of functional groups corresponding to the F. solanifungal supernatant for the synthesis of CeO sub(2) nanoparticles was studied by Fourier transform infrared (FTIR) spectroscopy. The room temperature photoluminescence spectrum of calcined CeO sub(2) nanopowder was recorded. Field emission scanning electron microscopy (FESEM) equipped with energy dispersive X-ray spectroscopy (EDAX) ascertained the formation of homogeneously distributed spherically shaped CeO sub(2) nanoparticles. Furthermore, transmission electron microscopy (TEM) demonstrated the spherical morphology of the CeO sub(2) nanoparticles having sizes ranging from 20 to 30 nm and also the selected area electron diffraction (SAED) pattern revealed the polycrystalline nature of the CeO sub(2) nanoparticles, which is consistent with the XRD results. The presence of surface oxidation states Ce (3d) and O (1s) of the CeO sub(2) nanoparticles was confirmed by X-ray Phoelectron Spectroscopy (XPS) analysis. The antibacterial activity of CeO sub(2) nanoparticles was evaluated by the disc diffusion method and it showed the highest activity against P. aeruginosaas well as K. pneumoniae. In addition, the inhibition on biofilm formation by CeO sub(2) nanoparticles has also been examined by confocal laser scanning microscopy (CLSM). Furthermore, the electrochemical property of the biosynthesized CeO sub(2) nanoparticles was studied by the cyclic voltammetry technique.