Chemical produced by mould Penicillium notatum did not allow the growth of Staphylococci bacteria, thus penicillin was established as antibiotic. Who established its effective potential ?

Options

A. Alexander Fleming
B. Ernest Chain
C. Ernest Chain and Howard Florey
D. Fleming and Waksman

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who established the effective potential of penicillin, which is an antibiotic produced by the mold Penicillium notatum. It is important to differentiate between the discovery of penicillin and the establishment of its effectiveness against diseases.

2. **Discovery of Penicillin**: Penicillin was discovered by Alexander Fleming in 1928. He observed that the mold Penicillium notatum inhibited the growth of Staphylococcus bacteria in his laboratory. This was an accidental discovery when he returned from vacation and found mold growing on his bacterial cultures.

3. **Establishing Effective Potential**: While Fleming discovered penicillin, the effective potential of penicillin as an antibiotic was established through clinical trials. This was done by Sir Ernst Boris Chain and Howard Walter Florey. They worked together to purify penicillin and conducted experiments to demonstrate its effectiveness in treating bacterial infections.

4. **Conclusion**: Therefore, the correct answer to the question is that Sir Ernst Boris Chain and Howard Walter Florey established the effective potential of penicillin through their clinical trials.

**Final Answer**: Sir Ernst Boris Chain and Howard Walter Florey established the effective potential of penicillin.

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