Microorganism used for commercial production of acetic acid is

Options

A. Saccharomyces cerevisiae
B. Acetobacter
C. Aspergillus niger
D. Clostridium butylicum

Answer

To answer the question regarding the microorganism used for the commercial production of acetic acid, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The options provided are:
- A) Saccharomyces cerevisiae
- B) Acetobacter
- C) Aspergillus niger
- D) Clostridium butylicum

2. **Analyze Each Option**:
- **Option A: Saccharomyces cerevisiae**: This is a yeast commonly used in the fermentation of beverages like wine and beer, but it is not primarily used for acetic acid production.
- **Option B: Acetobacter**: This is a genus of bacteria known specifically for its role in converting ethanol into acetic acid. It is the primary microorganism used in the commercial production of acetic acid.
- **Option C: Aspergillus niger**: This is a fungus used mainly for the production of citric acid, not acetic acid.
- **Option D: Clostridium butylicum**: This bacterium is involved in the production of butyric acid, which is unrelated to acetic acid.

3. **Conclusion**: Based on the analysis, the microorganism used for the commercial production of acetic acid is **Acetobacter**.

### Final Answer:
The microorganism used for commercial production of acetic acid is **Acetobacter** (Option B).

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