Question

Which of the following is used as precursor for the fermentation production of Penicillin?

• A. \( \text{Sulfite waste liquor} \)
• B. \( \text{Corn steep liquor} \)
• C. \( \text{Propionate} \)
• D. \( \text{Cyanide} \)

Hint:

Adding Phenylacetic acid specifically yields Penicillin G, while adding Phenoxyacetic acid yields Penicillin V.

Answer 1

The Correct Option is B

Concept: The large-scale production of penicillin involves complex fermentation media that provide nitrogen, minerals, and precursors.
• A precursor is a specific molecule added to the media to be incorporated into the final product.
• In early penicillin production, yield was significantly limited until the right additives were found.

Step 1: Historical Context of Penicillin Production.
In the 1940s, researchers discovered that adding certain agricultural by-products improved penicillin yield. Corn steep liquor (CSL), a concentrated byproduct of corn wet-milling, was found to be the most effective.

Step 2: The role of CSL as a source.
CSL is rich in organic nitrogen and provides natural precursors like phenylacetic acid. These precursors are directly incorporated into the side chain of the penicillin molecule (specifically Penicillin G). Therefore, CSL acts both as a primary nutrient and as a source of side-chain precursors. Final Answer: Corn steep liquor is the standard precursor/additive used in the fermentation production of Penicillin.