Which scientist discovered penicillin in 1928?

Alexander Fleming discovered penicillin in 1928. The Scottish bacteriologist noticed that a mould contaminating a Staphylococcus culture had created a clear zone where bacteria did not grow. He identified the mould as belonging to the Penicillium genus and called the antibacterial substance penicillin.

Fleming published his findings in 1929, but the discovery did not immediately become a widely available medicine. Researchers at the University of Oxford, including Howard Florey and Ernst Chain, later developed methods to purify and produce penicillin in useful quantities.

Mass production during the Second World War transformed penicillin into a practical treatment for serious bacterial infections. Fleming, Florey and Chain shared the 1945 Nobel Prize in Physiology or Medicine. Fleming’s discovery is often simplified as an accidental event, but recognizing the significance of the mould’s effect required careful observation and microbiological expertise.