A large number of antibiotics have been isolated from

Options

A. Bacteria actinomycetes
B. Bacteria staphylococcus
C. Bacteria rhizobium
D. Acids

Answer

**Step-by-Step Solution:**

1. **Understanding Antibiotics**:
- Antibiotics are substances that help combat infections caused by bacteria. They work by either killing the bacteria or inhibiting their ability to reproduce.

2. **Definition of Antibiotic**:
- The term "antibiotic" literally means "against life," which refers to their function of targeting living bacteria that cause infections.

3. **Sources of Antibiotics**:
- A significant number of antibiotics are derived from natural sources, particularly from certain types of bacteria and fungi.

4. **Identifying the Source**:
- Among the various sources, one of the most important groups of bacteria known for producing antibiotics is the Actinomycetes.

5. **Characteristics of Actinomycetes**:
- Actinomycetes are a group of bacteria that are characterized by their filamentous structure, resembling fungi. They form a branching network of filaments, which is crucial for their ability to produce various bioactive compounds, including antibiotics.

6. **Conclusion**:
- Therefore, the answer to the question "A large number of antibiotics have been isolated from" is **bacteria Actinomycetes**.

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