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Published on: September 28, 2018
Computer control of the penicillin fermentation using the filtration probe in conjunction with a structured process
1Department of Nutrition and Food Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139.
Biotechnology and Bioengineering
|March 1, 1983
Summary
A new penicillin fermentation model identifies key cell types and prevents cell degeneration by maintaining specific growth rates. This model enables effective computer control for optimized penicillin production.
Area of Science:
- Biotechnology
- Microbial Fermentation
- Biochemical Engineering
Background:
- Penicillin fermentation involves complex cellular processes.
- Cell degeneration, a loss of cytoplasmic material, impacts production efficiency.
- Understanding cell dynamics is crucial for process optimization.
Purpose of the Study:
- To present a structured model for penicillin fermentation.
- To incorporate three distinct cell types: hyphae tips, penicillin-producing cells, and degenerated cells.
- To analyze and control cell degeneration during fermentation.
Main Methods:
- Developed a structured model with three cell types.
- Quantified cell degeneration rate as a linear function of specific growth rate.
- Implemented open-loop and closed-loop computer control strategies.
- Utilized biomass concentration feedback via a filtration probe for closed-loop control.
Main Results:
- Identified a minimum specific growth rate (0.0115 h(-1)) to prevent cell degeneration.
- Demonstrated the model's utility as a control basis for fermentation.
- Showcased the necessity of closed-loop control when complex nutrients significantly impact biomass.
Conclusions:
- The structured model effectively represents penicillin-producing microbial populations.
- Controlling specific growth rate is key to preventing cell degeneration and maximizing yield.
- Advanced control strategies, like closed-loop systems, are vital for complex fermentation environments.
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