(a) Why is the used medium drained out from one side while fresh medium is added from the other? Explain.

Question

When the gene product is required in large amounts, the transformed bacteria with the plasmid inside the bacteria are cultured on a large scale in an industrial fermenter which then synthesizes the desired protein. This product is extracted from the fermenter for commercial use.

(a)  Why is the used medium drained out from one side while fresh medium is added from the other? Explain. 

(b)  List any four optimum conditions for achieving the desired product in a bioreactor.

Answer 1

(a)  To maintain the cells in their physiologically most active log/exponential phase.

(b)  Temperature, pH, substrate, salts, vitamins, oxygen