Download A new era of heavy metal bioremediation with carbonized

A new era of heavy metal bioremediation with carbonized Aspergillus
sp cell adhered silver nanoparticle
Triparna Mukherjee1, Shatarupa Chakraborty1and Tapan Kumar Das1*
Department of Biochemistry and Biophysics, University of Kalyani, Kalyani – 741235, India
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1*
Correspondent author email: [email protected]
Telephone: +91-3473-238373 (Res); +919475944385 (Mob)
Fax: +91-33-25828282
Now a day, heavy metal pollution has become a major environmental concern
throughout the world. Bioremediation with microorganism is a greener way to solve this
problem. On the other hand nanoscience and nanotechnology and their application
have altered the direction of science in a smarter way. So we conjugated these two
views to achieve best results in bioremediation with a carbonized novel strain of
Aspergillus sp cell adhered silver nanoparticle. Biological reduction of silver was done in
presence of the fungus Aspergillus foetidus MTCC8876 which was isolated from Kalyani
waste water treatment Centre. The cell suspended in silver solution was found to
Change into brownish color when the fungal strain of A.foetidus was challenged with
AgNO3 solution. The UV–visible spectrum of the fungal cell showed a peak at 430 nm
corresponding to the surface plasmon absorbance of silver nanoparticles.The
Aspergillus cells after bioreduction of silver were harvested and made into carbon at
400 °C for 1 h and its characterization carried out by the biophysical methods like
Fourier Transform Infra-Red spectroscopy, X-ray diffraction, scanning electron
microscope, transmission electron microscope attached with energy dispersive
spectroscopy. The average size of the silver nanoparticles present on the surface of the
carbonized silver containing Aspergillus sp cells was 30-40nm. The carbonized control
fungal cell did not contain any particles on its surface This carbonization made the cell
porous in such a way, so that the carbonized Aspergillus cell adhered silver
nanoparticle became suitable for high level of water purification with respect to both
heavy metal removal and microbial decontamination of drinking water in water
purification plant.