For the commercial and industrial production of Citric acid,which of the following microbes is used?

Options

A. Aspergillus niger
B. Lactobacillus sp
C. Saccharomyces cerevisiae
D. Clostridium butylicum

Answer

To determine which microbe is used for the commercial and industrial production of citric acid, we will analyze the given options step by step.

### Step-by-Step Solution:

1. **Understanding Citric Acid Production**:
- Citric acid is an organic acid that is widely used in food, pharmaceuticals, and other industries. It is primarily produced through fermentation processes.

2. **Analyzing the Options**:
- **Option A: Aspergillus niger**
- This is a type of fungus that is well-known for its ability to produce citric acid. It is commonly used in industrial fermentation processes for the production of citric acid.

- **Option B: Lactobacillus**
- This is a genus of bacteria primarily involved in the fermentation of milk to produce yogurt and other dairy products. It is not used for citric acid production.

- **Option C: Saccharomyces cerevisiae**
- This is a species of yeast commonly known as Baker's yeast. It is primarily used in baking and brewing, not for citric acid production.

- **Option D: Clostridium butylicum**
- This bacterium is involved in the production of butyric acid and is not associated with citric acid production.

3. **Conclusion**:
- After analyzing all the options, it is clear that **Aspergillus niger** (Option A) is the correct answer as it is the microbe used for the commercial and industrial production of citric acid.

### Final Answer:
**Aspergillus niger** is the microbe used for the commercial and industrial production of citric acid.

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