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Oxygen transfer in solid-state cultivation under controlled moisture conditions.
R G Bastos1, F L Motta, M H A Santana
1Development of Biotechnological Processes Laboratory, School of Chemical Engineering, University of Campinas, Campinas, São Paulo, 13083-852, Brazil.
Applied Biochemistry and Biotechnology
|August 4, 2014
Summary
This study investigated oxygen transfer in solid-state cultivation of Drechslera monoceras. Optimal moisture content (35%) improved oxygen transfer, while higher moisture (45%) enhanced biomass growth, highlighting a critical balance for fermentation.
Area of Science:
- Biotechnology
- Microbial Physiology
- Biochemical Engineering
Background:
- Solid-state cultivation (SSC) is a fermentation method using minimal water.
- Oxygen transfer is crucial for aerobic microbial growth in SSC.
- Controlling initial moisture content impacts biofilm formation and oxygen availability.
Purpose of the Study:
- To investigate oxygen transfer dynamics in SSC as a function of initial moisture content.
- To determine the optimal moisture level for enhanced oxygen mass transfer coefficient (KLa).
- To understand the relationship between moisture, biofilm characteristics, and biomass production in Drechslera monoceras cultivation.
Main Methods:
- Solid-state cultivation of Drechslera (Helminthosporium) monoceras on wheat bran in a packed bed column bioreactor.
- Controlled moisture conditions were maintained throughout the cultivation process.
- Pseudo-steady-state model was employed to estimate the overall oxygen mass transfer coefficient (KLa).
Main Results:
- An optimal initial moisture content of 35% was identified, leading to reduced biofilm thickness and improved KLa.
- Higher moisture content (45%) resulted in increased biomass growth.
- Distinct biomass growth patterns were observed, indicating the importance of balancing aerial and film growth.
Conclusions:
- Initial moisture content significantly influences oxygen transfer and biomass yield in SSC.
- Optimizing moisture levels is key for efficient KLa and biomass production in D. monoceras fermentation.
- Findings aid in optimizing SSC processes for allergen production and understanding oxygen dynamics in microbial fermentations.
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