Initial discovery of antibiotic penicillin was done by

The initial discovery of penicillin was made by Alexander Fleming in 1928 [1]. While working as a bacteriologist at St. Mary's Hospital in London, Fleming returned from a vacation to find a mold, later identified as Penicillium notatum, contaminating a petri dish of Staphylococcus bacteria [1]. He observed that the mold released a substance that inhibited bacterial growth, which he named penicillin [2]. Although Fleming published his findings in 1929, the substance was difficult to isolate in large quantities [3]. It was not until the late 1930s and early 1940s that scientists Howard Florey and Ernst Chain developed methods for mass production and clinical use [3]. In contrast, Francis Crick and Maurice Wilkins are renowned for their work on the structure of DNA, and Charles Darwin is famous for the theory of natural selection.

Sources

1. [1] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 3: Health: The Ultimate Treasure > Discovery of the first antibiotic, Penicillin > p. 40
2. [2] https://en.wikipedia.org/wiki/Discovery_of_penicillin
3. [3] https://pmc.ncbi.nlm.nih.gov/articles/PMC4520913/