Penicillin Mold Culture

A contaminated petri dish that saved millions of lives/Inventions & Discoveries

In 1928, Alexander Fleming noticed that a mold colony of Penicillium notatum had contaminated one of his staphylococcus cultures, creating a bacteria-free zone around it. The original petri dish was about 9 cm in diameter, and the mold colony measured roughly 2 cm across. This accidental discovery led to the development of penicillin, the first widely used antibiotic, which has since saved an estimated 200 million lives.