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Molecular Entanglement and Electrospinnability of Biopolymers
Published on: September 3, 2014
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Flocculation and antimicrobial properties of a cationized starch
Zhouzhou Liu1, Mu Huang1, Aimin Li1
1State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China.
Water Research
|April 25, 2017
Summary
Cationized starch-based flocculants (St-CTA) effectively remove contaminants like kaolin and bacteria. These St-CTA materials show enhanced antibacterial activity against E. coli compared to S. aureus due to cell wall differences.
Area of Science:
- Polymer Chemistry
- Environmental Science
- Biotechnology
Background:
- Starch-based flocculants offer a sustainable alternative for water treatment.
- Quaternary ammonium salt (QAS) compounds are known for their antimicrobial properties.
- Developing efficient and eco-friendly flocculants is crucial for environmental remediation.
Purpose of the Study:
- To synthesize and characterize novel cationized starch-based flocculants (St-CTA).
- To evaluate the flocculation efficiency of St-CTA for kaolin and bacterial suspensions.
- To assess the antibacterial activity of St-CTA against Gram-negative and Gram-positive bacteria.
Main Methods:
- Etherification reaction to prepare St-CTA with varying QAS substitution degrees.
- Flocculation tests using kaolin, Escherichia coli, and Staphylococcus aureus suspensions.
- Antibacterial assays including 3D excitation-emission matrix spectra and scanning electron microscopy (SEM).
Main Results:
- All prepared St-CTA flocculants demonstrated effective flocculation across various conditions.
- Higher QAS substitution in St-CTA led to improved contaminant removal via charge neutralization.
- St-CTA exhibited stronger antibacterial effects against E. coli than S. aureus.
- SEM analysis revealed differences in cell wall damage, explaining varying antibacterial efficacy.
Conclusions:
- Cationized starch-based flocculants (St-CTA) are effective for water purification and contaminant removal.
- The degree of QAS substitution significantly influences flocculation and antibacterial performance.
- St-CTA shows differential antibacterial activity against bacteria based on cell wall structure, with greater efficacy against E. coli.
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