Aspergillus species are important in industries as they produce

Options

A. citric acids, gluconic acid and oxalic acid
B. Ergot
C. Litmus
D. all of the above.

Answer

### Step-by-Step Solution:

1. **Identify Aspergillus**: Aspergillus is a genus of fungi, commonly referred to as molds. It is recognized for its significant economic importance in various industries.

2. **Understand Economic Importance**: Aspergillus species are considered prominent molds due to their ability to produce various compounds that are valuable in industrial applications.

3. **List the Products**: Aspergillus species are known for producing several important substances, including:
- **Citric Acid**: Widely used in food and beverage industries as a preservative and flavoring agent.
- **Oxalic Acid**: Used in various applications, including cleaning agents and as a bleaching agent.
- **Gluconic Acid**: Utilized in food, pharmaceuticals, and as a chelating agent.
- **Enzymes**: Aspergillus produces various enzymes that are crucial in biochemical processes, including the production of antibiotics.

4. **Conclude the Answer**: Given the various products produced by Aspergillus, it is clear that these fungi play a vital role in industrial processes, particularly in the production of citric acid, oxalic acid, and gluconic acid.

### Final Answer:
Aspergillus species are important in industries as they produce citric acid, oxalic acid, and gluconic acid.

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