Pure culture of bacteria was first obtained by

Options

A. R. Koch
B. L.Pasture
C. A. Leeuwenhock
D. J.Lister

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question is asking who first obtained a pure culture of bacteria.

2. **Consider the Options**: The options provided include notable figures in microbiology: Robert Koch, Louis Pasteur, Antonie van Leeuwenhoek, and Joseph Lister.

3. **Analyze Robert Koch's Contributions**: Robert Koch is known for his work on anthrax and tuberculosis. He developed methods to isolate bacteria and was instrumental in establishing the germ theory of disease. He is credited with obtaining a pure culture of the anthrax bacillus from infected animals.

4. **Evaluate Louis Pasteur's Role**: Louis Pasteur made significant contributions to microbiology, including the development of the germ theory and the process of pasteurization. However, he did not specifically isolate bacteria in pure culture as Koch did.

5. **Review Antonie van Leeuwenhoek's Work**: Leeuwenhoek is known as the father of microbiology and was the first to observe and describe microorganisms, but he did not develop methods for obtaining pure cultures.

6. **Consider Joseph Lister's Contributions**: Joseph Lister is known for his work in antiseptics and surgical procedures but did not focus on pure cultures of bacteria.

7. **Conclusion**: Based on the analysis, Robert Koch is the correct answer as he was the first to successfully obtain a pure culture of bacteria, specifically the anthrax bacillus.

**Final Answer**: Robert Koch.

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