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Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
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Competition for electrons between pyridine and quinoline during their simultaneous biodegradation
Hua Xu1, Weihua Sun2, Ning Yan1
1Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai, 200234, People's Republic of China.
Environmental Science and Pollution Research International
|September 19, 2017
Summary
Simultaneous biodegradation of pyridine and quinoline slowed removal rates due to competition for electron donors. Pyridine biodegradation was more inhibited than quinoline biodegradation.
Area of Science:
- Environmental microbiology
- Biotechnology
- Bioremediation
Background:
- Biodegradation of pyridine and quinoline initiates with mono-oxygenation, requiring intracellular electron donors.
- Simultaneous biodegradation of these compounds can lead to competition for electron donors, potentially inhibiting mono-oxygenation steps.
Purpose of the Study:
- To evaluate the impact of competition for intracellular electron donors during simultaneous pyridine and quinoline biodegradation.
- To assess the effectiveness of an internal circulation baffled biofilm reactor (ICBBR) in managing this competition.
Main Methods:
- Utilized an internal circulation baffled biofilm reactor (ICBBR) to study pyridine and quinoline biodegradation.
- Compared simultaneous biodegradation rates with independent biodegradation rates.
- Investigated the effect of adding exogenous electron donors.
- Evaluated biodegradation in actual coking wastewater.
Main Results:
- Simultaneous biodegradation slowed pyridine and quinoline removal rates compared to independent biodegradation, with pyridine removal being more affected.
- The initial mono-oxygenation of quinoline was consistently faster than pyridine, a difference amplified during simultaneous biodegradation due to electron donor competition.
- Competition also affected second mono-oxygenations, with 2-hydroxypyridine removal faster than 2-hydroxyquinoline.
- Exogenous electron donor addition accelerated mono-oxygenations, with greater increases for quinoline due to its higher affinity for donors.
- Competitive trends were observed in actual coking wastewater.
Conclusions:
- Competition for intracellular electron donors significantly impacts pyridine and quinoline biodegradation rates.
- Pyridine biodegradation is more susceptible to inhibition than quinoline biodegradation under competitive conditions.
- The ICBBR is a viable system for studying microbial competition in biodegradation processes.
- Supplementation with exogenous electron donors can mitigate competitive inhibition, with differential effects based on substrate affinity.
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