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Updated: Jul 6, 2026
12:54
Operation of a Benchtop Bioreactor
Published on: September 12, 2013
Oxygen-controlled biosurfactant production in a bench scale bioreactor
Frederico de Araujo Kronemberger1, Lidia Maria Melo Santa Anna, Ana Carolina Loureiro Brito Fernandes
1Programa de Engenharia Química, Instituto Alberto Luiz Coimbra de Pós Graduação e Pesquisa de Engenharia, Universidade Federal do Rio de Janeiro, Centro de Tecnologia, Rio de Janeiro, Brazil. frederico@peq.coppe.ufrj.br
Applied Biochemistry and Biotechnology
|April 11, 2008
Summary
This study optimized biosurfactant production using Pseudomonas aeruginosa in a bioreactor by controlling oxygen levels. Researchers monitored oxygen uptake to understand its impact on bacterial growth and rhamnolipid yield.
Area of Science:
- Microbiology
- Biotechnology
- Biochemical Engineering
Background:
- Rhamnolipids are effective biosurfactants with significant industrial potential.
- Pseudomonas aeruginosa is a key microorganism for aerobic rhamnolipid production.
- Optimizing production conditions, particularly oxygen availability, is crucial for efficient biosurfactant yield.
Purpose of the Study:
- To produce rhamnolipid biosurfactants using a Pseudomonas aeruginosa strain isolated from oil environments.
- To develop and utilize a nondispersive oxygenation device for precise dissolved oxygen (DO) control in a bench-scale bioreactor.
- To investigate the relationship between oxygen uptake rate (OUR), specific OUR (SOUR), bacterial growth, carbon source consumption, and rhamnolipid production.
Main Methods:
- Isolation and cultivation of Pseudomonas aeruginosa from oil-contaminated environments.
- Development of a bench-scale bioreactor system with a nondispersive oxygenation device and a programmable logic controller (PLC) for DO control.
- Measurement of oxygen uptake rate (OUR) and specific OUR (SOUR) at various DO concentrations.
- Analysis of bacterial growth, carbon source consumption, and rhamnolipid production.
Main Results:
- The specific OUR (SOUR) varied significantly with bacterial growth phases, starting at approximately 60.0 mgO(2)/g(DW) h, increasing during exponential growth, and decreasing to around 20.0 mgO(2)/g(DW) h.
- Carbon source consumption remained linear throughout the entire fermentation process.
- A correlation was observed between DO concentrations, SOUR, bacterial growth, and rhamnolipid production, indicating oxygen's critical role.
Conclusions:
- Precise control of dissolved oxygen in bioreactors is essential for optimizing Pseudomonas aeruginosa growth and rhamnolipid biosurfactant production.
- Understanding the oxygen metabolism of Pseudomonas aeruginosa, as indicated by SOUR, provides insights into maximizing biosurfactant yield.
- This study demonstrates a method for enhancing biosurfactant production through controlled aeration in bioreactor systems.
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