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Solubilization and Bio-conjugation of Quantum Dots and Bacterial Toxicity Assays by Growth Curve and Plate Count
Published on: July 11, 2012
Silver nanoparticles tolerant bacteria from sewage environment.
Sudheer Khan1, Amitava Mukherjee, Natarajan Chandrasekaran
1Nanobio-Medicine Laboratory, School of Bio-Sciences and Technology, VIT University, Vellore 632014, India. sudheerkhan@vit.ac.in
Journal of Environmental Sciences (China)
|April 27, 2011
Summary
Environmental bacteria like Bacillus pumilus can protect ecosystems from harmful silver nanoparticles (SNPs). Bacterial exopolysaccharides cap SNPs, reducing their toxicity to other microbes and potentially mitigating environmental risks.
Area of Science:
- Environmental Science
- Microbiology
- Nanotechnology
Background:
- Silver nanoparticles (SNPs) pose significant risks to soil, water, and human health, necessitating environmental protection strategies.
- Microbial tolerance and interaction mechanisms with nanomaterials are crucial for understanding environmental impacts.
Purpose of the Study:
- To investigate the interaction between Bacillus pumilus and silver nanoparticles.
- To determine if bacterial exopolysaccharides can mitigate SNP toxicity.
Main Methods:
- Bacterial growth kinetics analysis of Bacillus pumilus with and without SNPs.
- Characterization of exopolysaccharides using UV-Visible, Fourier Transform Infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD).
- Assessment of toxicity of SNP-exopolysaccharide complexes against E. coli, S. aureus, and M. luteus.
Main Results:
- Bacillus pumilus exhibited similar growth kinetics in the presence or absence of SNPs.
- Exopolysaccharides from Bacillus pumilus were found to cap silver nanoparticles.
- Exopolysaccharide-capped SNPs demonstrated reduced toxicity to tested bacterial strains compared to uncoated SNPs.
Conclusions:
- Bacterial exopolysaccharides play a role in mitigating the toxicity of silver nanoparticles.
- Exopolysaccharide capping of SNPs is a probable mechanism for bacterial tolerance to silver nanoparticles.
- This finding suggests a potential bioremediation strategy for silver nanoparticle pollution.
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