Citric acid is got from

Options

A. Aspergillus niger
B. Rhizobium nigrificans
C. Penicillium citrinum
D. Lactobacillus bulgaricus

Answer

**Step-by-Step Solution:**

1. **Understanding Citric Acid**: Citric acid is an organic compound that is commonly used as a natural preservative and to add an acidic or sour taste to foods and beverages.

2. **Identifying Microbial Sources**: Citric acid can be produced by various microorganisms through the fermentation process. This involves the conversion of carbohydrates into organic compounds.

3. **Analyzing the Options**:
- **Option 1: Aspergillus niger**: This is a type of fungus known for its ability to ferment sugars and produce citric acid.
- **Option 2: Rhizobium nigrificants**: This is a genus of bacteria primarily known for nitrogen fixation in legumes, not citric acid production.
- **Option 3: Penicillium citrinum**: While this fungus is known for producing citrinin, it is not the primary source of citric acid.
- **Option 4: Lactobacillus vulgaricus**: This bacterium is primarily involved in lactic acid fermentation, not citric acid production.

4. **Conclusion**: Based on the analysis, the correct answer is **Aspergillus niger**, as it is the microorganism that is widely used for the industrial production of citric acid.

**Final Answer**: Citric acid is obtained from **Aspergillus niger**.

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