Related Experiment Video
Updated: Jul 4, 2026

07:38
Saccharomyces cerevisiae Exponential Growth Kinetics in Batch Culture to Analyze Respiratory and Fermentative Metabolism
Published on: September 30, 2018
Profile control scheme in a Bakers' yeast fed-batch culture
T Takamatsu1, S Shioya, Y Okada
1Department of Chemical Engineering, Kyoto University, Kyoto, 606 Japan.
Biotechnology and Bioengineering
|December 1, 1985
Summary
This study introduces a computer control system for precise biomass and growth rate tracking. The programmed-controller/feedback-compensator (PF) system, enhanced with model reference adaptive control (MRAC), effectively manages microbial growth profiles.
Area of Science:
- Biotechnology
- Control Systems Engineering
- Bioprocess Engineering
Background:
- Accurate control of biomass concentration and specific growth rate is crucial for optimizing bioprocesses.
- Existing control strategies may struggle with noise and model parameter uncertainties.
Purpose of the Study:
- To develop and validate a practical computer control scheme for precise profile following of biomass concentration and specific growth rate.
- To introduce a novel control system integrating programmed control with adaptive feedback compensation.
Main Methods:
- Development of the programmed-controller/feedback-compensator (PF) system.
- Integration of the model reference adaptive control (MRAC) algorithm as a feedback compensator.
- Addition of a predictive control algorithm for cell concentration control, forming the PFP system.
Main Results:
- Computer simulations confirmed the validity and effectiveness of the proposed PF system.
- The PF system combined with MRAC (PF-MRAC) demonstrated sufficient performance for specific growth rate profile control.
- The PFP system, incorporating predictive control and MRAC (PFP-MRAC), showed excellent performance for cell concentration profile control.
Conclusions:
- The proposed PF and PFP systems, particularly with MRAC, offer robust and accurate solutions for bioprocess profile control.
- These advanced control schemes effectively handle disturbances and model uncertainties, enhancing bioprocess predictability and optimization.
Related Concept Videos
Bioreactor Controls-III
Strain improvement is a foundational strategy in industrial microbiology aimed at maximizing microbial productivity, particularly because natural isolates typically yield commercially valuable products in very low concentrations. Although optimizing the culture medium and environmental conditions can improve yields, these adjustments are inherently limited by the organism’s genetic potential. As a result, the focus shifts toward genetic modifications to enhance biosynthetic capacity. The...
Fed-Batch Culture
Fed-batch culture is a widely used bioprocessing strategy combining aspects of batch culture with controlled substrate feeding to optimize cell growth and product formation. In this semi-closed system, nutrients are strategically added during fermentation, while the accumulated products and biomass remain within the bioreactor until the end of the operation. This controlled addition of substrates allows for better management of growth kinetics, nutrient limitation, and metabolite...
Bioreactor Controls-I
Maintaining optimal conditions within fermenters is essential for maximizing microbial productivity and ensuring process efficiency. This lesson focuses on key parameters—temperature, foam, pH, carbon dioxide, oxygen, and pressure—and their precise measurement and control strategies in fermentation systems.Temperature ControlTemperature regulation is critical due to the exothermic nature of many fermentation processes. In small laboratory fermenters, temperature is commonly monitored using...
Production of Alcohol
Continuous fermentation is a key strategy in industrial ethanol production, particularly when efficiency, scalability, and high yields are essential. This approach allows for uninterrupted operation and optimized resource utilization. The primary feedstock, corn starch, undergoes enzymatic hydrolysis facilitated by α-amylase and glucoamylase. These enzymes break down the starch into fermentable sugars such as glucose, which are readily assimilated by fermentative microorganisms.Fermentation...
Bioreactor Controls-II
In aerobic fermentations, oxygen is vital for microbial growth and metabolite production. Since air comprises only about 20% oxygen and the gas is poorly soluble in water—just 9 ppm at 20°C—supplying sufficient oxygen becomes a critical challenge, especially in high-demand processes like yeast growth or citric acid production. Even a fully saturated broth may offer only a few seconds of oxygen availability.To address this, sterile or scrubbed air is introduced into the fermentor via a sparger...
Batch vs Continuous Culture
Fermentation is a foundational biotechnological process used to produce pharmaceuticals, biofuels, enzymes, and food additives. Among industrial strategies, batch and continuous fermentation are the two most widely applied. Although both rely on microbial conversion of substrates into desired products, they differ markedly in operation, productivity, and suitability for specific applications.Batch fermentation occurs in a closed system in which nutrient media and inoculum are added at the...

