Citric acid is industrially best produced by :

Options

A. Streptococcus lactis
B. Aspergillus niger
C. Penicillium purpurgenum
D. Lactobacillus

Answer

To solve the question about which organism is best for the industrial production of citric acid, we can follow these steps:

### Step 1: Identify the Organisms
We need to analyze the organisms mentioned in the question and their relevance to citric acid production. The options include:
- Streptococcus lactis
- Aspergillus niger
- Penicillium Perfungium
- Lactobacillus

### Step 2: Understand the Role of Each Organism
- **Streptococcus lactis**: Primarily involved in cheese production, not significant for citric acid.
- **Aspergillus niger**: A fungus known for its ability to produce citric acid on a large scale in industrial settings.
- **Penicillium Perfungium**: Related to antibiotic production, not known for citric acid production.
- **Lactobacillus**: Generally involved in fermentation processes, particularly in dairy, but not primarily for citric acid.

### Step 3: Determine the Best Option
From the analysis, **Aspergillus niger** is recognized as the most efficient organism for the industrial production of citric acid. It is widely used in fermentation processes to synthesize citric acid, making it the best choice among the options provided.

### Conclusion
The correct answer is **Aspergillus niger**.

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