Choose the following statements which are correct with respect to continuous culture systems:

(A) In simple stirred tank bioreactor, the stirring happens through sparging of air bubbles
(B) Bioreactor has an agitator system, oxygen delivery system and foam control system
(C) Sampling ports provides vents to withdraw small volumes of culture periodically
(D) Culturing in bio reactors is classified as downstream processing

Choose the correct answer from the options given below:

(B) and (C) only

The correct answer is Option (3) → (B) and (C) only

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).

A) In simple stirred tank bioreactor, the stirring happens through sparging of air bubbles:

• Incorrect:
• In a simple stirred tank bioreactor, stirring is achieved by mechanical agitation using an impeller, not just through sparging of air bubbles. Sparging is used for oxygen delivery but is separate from the stirring mechanism.

(B) Bioreactor has an agitator system, oxygen delivery system, and foam control system:

• Correct:
• A bioreactor includes an agitator system for mixing, an oxygen delivery system for aeration, and a foam control system to manage excess foam generated during the fermentation process.

(C) Sampling ports provide vents to withdraw small volumes of culture periodically:

• Correct:
• Sampling ports in bioreactors are used to withdraw small amounts of the culture for monitoring and analysis without disrupting the culture process.

(D) Culturing in bioreactors is classified as downstream processing:

• Incorrect:
• Culturing in bioreactors is part of upstream processing, which involves the preparation and growth of biological systems (e.g., microbes, cells).
• After completion of the biosynthetic stage, the product has to be subjected through a series of processes before it is ready for marketing as a finished product. The processes include separation and purification, which are collectively referred to as downstream processing.