title: Tolerance to silver of an Aspergillus fumigatus strain able to grow on cyanide containing wastes.
abstract: We studied the strategy of an Aspergillus fumigatus strain able to grow on metal cyanide wastes to cope with silver. The tolerance test revealed that the Minimum Inhibitory Concentration of Ag(I) was 6mM. In 1mM AgNO3 aqueous solution the fungus was able to reduce and sequestrate silver into the cell in the form of nanoparticles as evidenced by the change in color of the biomass and Electron Microscopy observations. Extracellular silver nanoparticle production also occurred in the filtrate solution after previous incubation of the fungus in sterile, double-distilled water for 72h, therefore evidencing that culture conditions may influence nanoparticle formation. The nanoparticles were characterized by UV-vis spectrometry, X-ray diffraction and Energy Dispersion X-ray analysis. Atomic absorption spectrometry revealed that the optimum culture conditions for silver absorption were at pH 8.5.The research is part of a polyphasic study concerning the behavior of the fungal strain in presence of metal cyanides; the results provide better understanding for further research targeted at a rationale use of the microorganism in bioremediation plans, also in view of possible metal recovery. Studies will be performed to verify if the fungus maintains its ability to produce nanoparticles using KAg(CN)2.
authors.affiliation: Department of Biomolecular Sciences, University of Urbino Carlo Bo, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Sabatini
authors.affiliation: Department of Earth, Life Sciences & Environment, University of Urbino Carlo Bo, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Battistelli
authors.affiliation: Department of Base Sciences and Foundations, Chemistry Section, University of Urbino Carlo Bo, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Giorgi
authors.affiliation: Department of Earth, Life Sciences & Environment, University of Urbino Carlo Bo, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Iacobucci
authors.affiliation: Department of Science and Engineering of Matter, of Environment and Urban Planning, Polytechnic University of Marche, Ancona, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Gobbi
authors.affiliation: Department of Biomolecular Sciences, University of Urbino Carlo Bo, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Andreozzi
authors.affiliation: Department of Biomolecular Sciences, University of Urbino Carlo Bo, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Pianetti
authors.affiliation: Department of Base Sciences and Foundations, Chemistry Section, University of Urbino Carlo Bo, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Franchi
authors.affiliation: Department of Biomolecular Sciences, University of Urbino Carlo Bo, Italy. Electronic address: francesca.bruscolini@uniurb.it.
authors.forename: F
authors.initials: F
authors.lastname: Bruscolini
mesh_terms: D001232:Aspergillus fumigatus / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D003486:Cyanides / Q000378:metabolism*; D053768:Metal Nanoparticles / Q000633:toxicity* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D012835:Silver Nitrate / Q000633:toxicity*
chemical_list: D003486:Cyanides; D012835:Silver Nitrate
keywords: Metal cyanide waste; Nanoparticle production; Silver tolerance