Tellurite biotransformation and detoxification by Shewanella baltica with simultaneous synthesis of tellurium nanorods exhibiting photo-catalytic and anti-biofilm activity.
Ecotoxicol Environ Saf
; 165: 516-526, 2018 Dec 15.
Article
em En
| MEDLINE
| ID: mdl-30223164
ABSTRACT
Tellurite reducing bacterial strain was isolated from Zuari estuary, Goa India which could tolerate 5.5â¯mM potassium tellurite with a minimum inhibitory concentration of 6â¯mM. This strain was designated as GUSDZ9 and was identified as Shewanella baltica (accession number MF350629) based on 16S rRNA gene sequencing and BLAST analysis. The Diethyl-dithiocarbamate based colorimetric analysis clearly demonstrated a complete reduction of 2â¯mM tellurite to elemental tellurium during the late stationary phase. Te Nanoparticles (TeNPs) biosynthesis which initiated at early log phase (i.e. 4â¯h) was evidently monitored through colour change and a peak due to surface plasmon resonance at 210â¯nm using UV-Vis spectroscopic analysis. X-ray crystallographic studies and transmission electron microscopy revealed unique nano-rods with a diameter ranging from 8 to 75â¯nm. Energy dispersive X-ray analysis further confirmed the presence of pure tellurium. The biogenic TeNPs at 10 and 5⯵g/mL evidently demonstrated 90% degradation of methylene blue dye and anti-biofilm activity against potential Gram-positive and Gram-negative human pathogens respectively. The alkaline comet assay revealed time and dose-dependent genotoxicity at concentrations higher than 15⯵g/mL of TeNPs. This study clearly demonstrated the potential of Shewanella baltica strain GUSDZ9 in bioremediation of toxic tellurite through bio-reduction into elemental tellurium and involvement of biogenic TeNPs in the photo-catalytic reduction of methylene blue and anti-biofilm activity. This is the first report of its kind on the synthesis of biogenic TeNPs from Shewanella baltica demonstrating photo-catalytic, anti-biofilm activity as well as genotoxicity.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Telúrio
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Biodegradação Ambiental
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Inativação Metabólica
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Shewanella
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Nanotubos
País/Região como assunto:
Asia
Idioma:
En
Revista:
Ecotoxicol Environ Saf
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Índia