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Published on: November 8, 2019
Enzymatic oxidation of aqueous pentachlorophenol
1Department of Chemical Engineering, The University of Seoul, Seoul 130-743, Korea. eykim@uos.ac.kr
Journal of Environmental Sciences (China)
|October 31, 2007
Summary
Tween 80 enhances pentachlorophenol removal by horseradish peroxidase at low concentrations by protecting the enzyme. However, at higher concentrations, it hinders removal by partitioning the pollutant into micelles.
Area of Science:
- Environmental Chemistry
- Biocatalysis
- Surfactant Science
Background:
- Pentachlorophenol (PCP) is a persistent organic pollutant.
- Horseradish peroxidase (HRP) is an enzyme used for pollutant degradation.
- Nonionic surfactants can affect enzymatic reactions.
Purpose of the Study:
- To investigate the effect of Tween 80 on PCP oxidation by HRP.
- To understand how Tween 80 concentration influences PCP removal and enzyme stability.
Main Methods:
- Enzymatic oxidation of PCP using HRP.
- Testing Tween 80 at concentrations below and above its critical micelle concentration (CMC).
- Monitoring PCP removal and enzyme inactivation over time.
Main Results:
- PCP removal was enhanced at sub-CMC concentrations of Tween 80.
- Tween 80 reduced enzyme inactivation by free radicals and product sorption.
- At supra-CMC concentrations, Tween 80 reduced PCP removal due to micelle partitioning.
Conclusions:
- Tween 80 can be beneficial for HRP-catalyzed PCP degradation at low concentrations.
- High concentrations of Tween 80 inhibit PCP removal by sequestering the pollutant.
- Understanding surfactant-enzyme-pollutant interactions is crucial for bioremediation strategies.
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