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Biotechnology: Principles and Processes — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYBiotechnology: Principles and Processes4 Marks
Question
Explain bioreactor with diagram.
✓

Answer

→ Small volume cultures cannot yield appreciable quantities of products.
→ To produce in large quantities, the development of bioreactors, where large volumes (100-1000 litres) of culture can be processed.
→ Thus, bioreactors can be thought of as vessels in which raw materials are biologically converted into specific products, individual enzymes, etc., using microbial plant, animal or human cells.
→ A bioreactor provides the optimal conditions for achieving the desired product by providing optimum growth conditions temperature, pH, substrate, salts, vitamins, oxygen etc.
→ The most commonly used bioreactors are of stirring type.
→ A stirred-tank reactor is usually cylindrical or with a curved base to facilitate the mixing of the reactor contents.
→ The stirrer facilitates even mixing and oxygen availability throughout the bioreactor.
→ Alternatively air can be bubbled through the reactor.
→ The bioreactor has an agitator system, an oxygen delivery system and a foam control system, a temperature control system, pH control system and sampling ports so that small volumes of the culture can be withdrawn periodically.
→ The cells can also be multiplied in a continuous culture system wherein the used medium is drained out from one side while fresh medium is added from the other to maintain the cells in their physiologically most active log/exponential phase.
→ This type of culturing method produces a larger biomass leading to higher yields of desired protein.
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