Question

Which of the following are the processes included in downstream processing?

• A. Expression and separation
• B. Selection and separation
• C. Separation and purification
• D. Selection and purification

Answer 1

The correct option is C Separation and purification

Biological reactions involving microbes which result in the formation of economically beneficial products such as enzymes, antibodies etc. are carried out in large vessels called the bioreactors.

This process can be divided into two steps.

• Upstream processing
• Downstream processing

Upstream processing involves all the steps till the desired product is ready to be harvested from the reactor. This involves selection of micro-organisms and the medium in which it needs to grow, providing suitable temperature, aeration and pH to the bioreactor and any other inputs required.

Downstream processing involves steps involved in extracting and purifying out the desired product from the bioreactor. This includes separating it out from the microbes, the nutrient medium and the other substances which are present inside the bioreactor first and then purifying it.

Therefore, separation and purification are the two main processes which are included in downstream processing.