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Updated: Aug 9, 2026
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Creating Rapid Oxygen Oscillations in Microbial Single-cell Growth Analysis using a Microfluidic Double-layer Device
Published on: July 18, 2025
Oxygen limitation is a pitfall during screening for industrial strains
Hartmut F Zimmermann1, Tibor Anderlei, Jochen Büchs
1Degussa AG, Rodenbacher Chaussee 4, 63457 Hanau (Wolfgang), Germany. hartmut.zimmermann@degussa.com
Applied Microbiology and Biotechnology
|April 1, 2006
Summary
Understanding oxygen transfer limitations is crucial for aerobic fermentation screening. Optimizing shake flask conditions prevents selecting suboptimal strains, ensuring efficient industrial amino acid production.
Area of Science:
- Biotechnology
- Microbial Physiology
- Biochemical Engineering
Background:
- Oxygen supply is critical for aerobic fermentation, particularly in industrial amino acid production.
- Oxygen transfer rate (OTR) is often overlooked in shake flask screening experiments by biologists.
- This oversight can lead to the selection of suboptimal microbial strains during early development.
Purpose of the Study:
- To highlight the importance of considering oxygen transfer limitations in primary screening experiments.
- To establish design criteria for improved shake flask bioreactor screening.
- To evaluate the suitability of a specific lysine-producing strain for industrial applications.
Main Methods:
- Cultivation of Corynebacterium glutamicum strains (wild-type and lysine-producing) in shake flasks with varied culture volumes and shaking conditions.
- Quasi-continuous determination of oxygen transfer rate (OTR) using a Respiration Activity Monitoring System.
- Off-line measurement of optical density, lysine, and byproduct concentrations (lactate, acetate, succinate) correlated with OTR.
Main Results:
- Oxygen transfer limitations were demonstrated to impact strain performance in shake flask cultures.
- Correlation established between OTR, cell growth, lysine production, and byproduct formation.
- Design criteria for optimizing shake flask conditions to avoid oxygen limitation were derived.
Conclusions:
- Proper management of oxygen transfer in shake flask screenings is essential for reliable strain selection.
- Optimized screening protocols can prevent the early-stage selection of suboptimal strains in bioprocess development.
- The lysine-producing strain DSM 12866 shows potential for high space-time yield in industrial fermentation.
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