Which of the following yeast is used for the production of riboflavin?
1. Saccharomyces rouxii
2. Saccharomyces cerevisiae
3. Eremotheciumashbyi
4. Candida utilis

Detailed Explanation:
Correct Answer:
3. Eremothecium ashbyi

Yeast and Riboflavin Production

Riboflavin, also known as Vitamin B2, is essential for various cellular functions, including energy production and the metabolism of fats, drugs, and steroids. Industrial production of riboflavin is commonly achieved through fermentation processes using specific types of yeast and fungi.

Eremothecium ashbyi: The Riboflavin Producer

Eremothecium ashbyi is a filamentous yeast species that is extensively used in the commercial production of riboflavin. This yeast is known for its high riboflavin-producing capability, making it an ideal candidate for large-scale industrial fermentation processes.

Why Other Options Are Incorrect:

• Saccharomyces rouxii (Option 1):
  While Saccharomyces rouxii is an important yeast in industrial applications, particularly in the production of certain fermented foods, it is not widely used for riboflavin production.

• Saccharomyces cerevisiae (Option 2):
  Saccharomyces cerevisiae is the most well-known yeast and is commonly used in baking, brewing, and genetic research. However, it is not the primary yeast used for the industrial production of riboflavin.

• Candida utilis (Option 4):
  Candida utilis is used in various industrial applications, including fermentation processes, but it is not typically used for riboflavin production.

Conclusion:

The correct yeast used for riboflavin production is Eremothecium ashbyi. This yeast plays a crucial role in the biotechnology industry for producing riboflavin on a large scale, and understanding its role highlights the importance of specific microorganisms in the biosynthesis of essential vitamins.