The first antibiotic discovered was

Options

A. Streptococcus
B. Staphylococcus
C. Lactobacillus
D. Saccharomyces

Answer

**Step-by-Step Solution:**

1. **Understanding Antibiotics**: Antibiotics are drugs that are specifically used to combat bacterial infections. They work by killing bacteria or inhibiting their growth.

2. **Identifying the First Antibiotic**: The first antibiotic discovered was penicillin. This significant discovery marked the beginning of modern antibiotics.

3. **Discovery Context**: Penicillin was discovered by Alexander Fleming in 1928. While working with Staphylococcus bacteria, he observed an interesting phenomenon.

4. **Observation of Mold**: Fleming noticed that on a culture plate where he was growing Staphylococcus, there was a mold growing. This mold was identified as Penicillium notatum.

5. **Effect of the Mold**: Fleming observed that the presence of Penicillium notatum inhibited the growth of Staphylococcus bacteria, leading to their death. This indicated that the mold produced a substance that was effective against bacteria.

6. **Significance of the Discovery**: The discovery of penicillin was crucial as it was highly effective against gram-positive bacteria, including Staphylococcus, and paved the way for the development of other antibiotics.

7. **Conclusion**: Therefore, the first antibiotic discovered was penicillin, which was identified by Alexander Fleming.

**Final Answer**: The first antibiotic discovered was penicillin.

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