Chloramphenicol and erythormycin (broad spectrum antibiotics) are produced by

Options

A. Rhizobium
B. Streptomyces
C. Penicillium
D. Nitrobacter.

Answer

**Step-by-Step Solution:**

1. **Identify the Antibiotics**: The question mentions two antibiotics: chloramphenicol and erythromycin. Both are known for their broad-spectrum antibacterial properties.

2. **Understand the Source of Antibiotics**: Antibiotics are often produced by microorganisms. In this case, we need to find out which organism produces both chloramphenicol and erythromycin.

3. **Review the Options**: The options provided are:
- A) Rhizobium
- B) Tryptomyces
- C) Penicillium
- D) Nitro bacteria

4. **Analyze Each Option**:
- **Rhizobium**: This is a genus of bacteria known for nitrogen fixation, not for antibiotic production.
- **Tryptomyces**: This option seems similar to Streptomyces, but it is not a recognized genus for antibiotic production.
- **Penicillium**: This is a genus known for producing penicillin, not chloramphenicol or erythromycin.
- **Nitro bacteria**: These bacteria are involved in nitrogen fixation and are not known for antibiotic production.

5. **Identify the Correct Answer**: The correct genus that produces both chloramphenicol and erythromycin is **Streptomyces**. Specifically, erythromycin is isolated from *Streptomyces erythreus*.

6. **Conclusion**: Therefore, the correct option is **B) Tryptomyces**.