Types of Bioreactors
Introduction
A bioreactor is a system or vessel designed to provide a controlled environment for the growth and metabolic activities of microorganisms, plant cells, or animal cells to produce desired biological products. Bioreactors are widely used in biotechnology, pharmaceuticals, and industrial processes.
Types of Bioreactors
Bioreactors can be classified based on design, mode of operation, and the type of organisms used.
A. Based on Mode of Operation
Batch Bioreactor
Operates in a closed system.
Nutrients are added at the start, and products are harvested at the end.
Used for small-scale production or specific processes like fermentation.
Continuous Bioreactor
Operates in an open system where nutrients are added continuously, and products are removed simultaneously.
Provides steady-state conditions, suitable for large-scale production.
Fed-Batch Bioreactor
A combination of batch and continuous systems.
Nutrients are added periodically without removing the culture.
Reduces nutrient limitation and substrate inhibition.
B. Based on Design and Functionality
Stirred Tank Bioreactor (STR)
Most common design.
Contains an agitator for mixing and aeration.
Suitable for both aerobic and anaerobic processes.
Air-Lift Bioreactor
Uses air or gas to mix the culture instead of mechanical stirring.
Energy-efficient and suitable for shear-sensitive cells.
Packed Bed Bioreactor
Contains immobilized cells or enzymes in a packed bed.
Suitable for continuous processes like wastewater treatment.
Fluidized Bed Bioreactor
Similar to a packed bed but with fluid flow to suspend particles.
Increases mass transfer and surface area.
Photo-Bioreactor
Uses light as an energy source.
Designed for growing photosynthetic organisms like algae.
Membrane Bioreactor
Combines biological processes with membrane filtration.
Used for wastewater treatment and high-value product recovery.
Bubble Column Bioreactor
Relies on gas bubbles for aeration and mixing.
Simple design with minimal mechanical parts.
C. Based on Application
Industrial Bioreactors
Large-scale systems for producing enzymes, biofuels, and other chemicals.
Medical Bioreactors
Used in tissue engineering or for producing pharmaceutical products like vaccines.
Research Bioreactors
Small-scale systems for experimental purposes and process optimization.
Conclusion
Bioreactors are versatile tools essential for industrial biotechnology, offering specific designs and modes of operation to suit diverse applications. Understanding their types helps in selecting the appropriate system for maximum efficiency and productivity.