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Air-stripping effects on cell growth with volatile substrates
1Department of Chemical Engineering, University of Saskatchewan, Saskatoon, Canada S7N OWO.
Biotechnology and Bioengineering
|September 1, 1987
Summary
Air stripping significantly impacts substrate removal in microbial cultures, affecting phenol concentration. This process is crucial for accurately modeling microbial growth, especially for Pseudomonas putida.
Area of Science:
- Microbiology
- Biochemical Engineering
- Environmental Science
Background:
- Substrate removal in aerobic microbial cultures involves microbial consumption and air stripping.
- Air stripping is a significant factor, particularly for volatile substrates at low concentrations.
- Accurate modeling of microbial growth necessitates accounting for air stripping effects.
Purpose of the Study:
- To quantify the air stripping parameter for phenol in microbial fermentation.
- To assess the role of air stripping in the decline of phenol concentration during Pseudomonas putida growth.
- To investigate the sensitivity of kinetic inhibition constants to air stripping and initial bacterial concentration.
Main Methods:
- Determined a constant air stripping parameter for phenol (0.0033 h⁻¹).
- Analyzed phenol removal in Pseudomonas putida cultures.
- Applied non-linear, least squares fitting to experimental data to determine inhibition constants.
Main Results:
- Air stripping accounted for the entire initial decline in phenol concentration for Pseudomonas putida.
- The kinetic inhibition constant is sensitive to the air stripping parameter and initial bacterial concentration.
- Isolated inhibition constants for phenol concentrations ranging from 100 to 600 ppm.
Conclusions:
- Air stripping is a critical, often dominant, removal mechanism for volatile substrates like phenol in microbial systems.
- Accurate microbial growth models must incorporate the air stripping parameter.
- Understanding the interplay between air stripping and bacterial kinetics is vital for optimizing fermentation processes.
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