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Quantification, Viability Assessment, and Visualization Strategies for Acinetobacter Biofilms
Published on: August 4, 2023
Involvement of Acinetobacter sp. in the floc-formation in activated sludge process
Kimchhayarasy Phuong1, Shohei Hanazaki, Kazuo Kakii
1Department of Material Science and Engineering, Graduate School of Engineering, Utsunomiya University, 7-1-2 Yoto, Utsunomiya 321-8585, Japan. ahsrors@gmail.com
Journal of Biotechnology
|October 18, 2011
Summary
Acinetobacter johnsonii S35 aids in wastewater treatment by promoting floc formation. This isolate effectively coaggregates with sewage bacteria, enhancing bioflocculation in activated sludge processes.
Area of Science:
- Environmental Microbiology
- Wastewater Treatment Technologies
- Bacterial Coaggregation
Background:
- Acinetobacter species are found in wastewater treatment plants, but their role in bioflocculation is not fully understood.
- Understanding bacterial interactions is crucial for optimizing wastewater treatment processes.
Purpose of the Study:
- To investigate the coaggregation behavior of Acinetobacter johnsonii S35 with sewage bacteria.
- To determine the potential of A. johnsonii S35 in contributing to floc formation in activated sludge.
Main Methods:
- Spectrophotometric assays were used to assess coaggregation between A. johnsonii S35 and various wastewater samples.
- Adsorption assays and microbial adhesion to hydrocarbon (MATH) tests were employed to evaluate cell surface properties.
Main Results:
- A. johnsonii S35 demonstrated significant coaggregation with free bacteria and microflocs (0.2:1-0.6:1 ratio), forming larger aggregates (≥100 μm).
- High adsorption rates (93-99%) of A. johnsonii S35 cells onto sludge samples were observed.
- Both A. johnsonii S35 and sludge samples exhibited hydrophobic characteristics.
Conclusions:
- Acinetobacter johnsonii S35 acts as a bridging organism, facilitating floc formation in activated sludge.
- The hydrophobic nature of A. johnsonii S35 contributes to its effective adsorption and coaggregation in wastewater environments.
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