History Podcasts

Who Discovered Penicillin?

Who Discovered Penicillin?

The discovery of penicillin has pioneered the invention of antibiotics that we take for granted today, but is still saving the lives of thousands of people every day. The person rightly credited for its discovery is sir Alexander Fleming, but the story does not stop there. Without the efforts of some other people, we would never have had antibiotics today

Accidental Discoveries

For some reason, Fleming had a knack for making accidental discoveries. His laboratory was not exactly tidy and he didn't always follow the correct protocols to keep samples from getting contaminated. He was, however looking for something that can kill bacteria as he was very convinced that the antiseptics used in common medical practise for deep wounds did more harm than good as it also killed the beneficial agents the body used as a immune response. Flemming's first accidental discovery was when some mucus from his nose dripped on a dish of bacteria he was working with. It killed some of the bacteria, which is how he discovered that an enzyme that naturally occurs in mucus and tears helps to defend the body from bacteria. His second discovery, that of penicillin happened in 1928 in a similar fashion. He went on holiday while still working on research on staphylococci. He had stacked cultures of this bacteria on a bench and discovered that one of the dishes was contaminated with a fungus. Further investigation showed that all of the staphylococci colonies around it were killed. He had discovered penicillin, but did not have the equipment or knowledge to develop it into the antibiotic we know it as today.

The Discovery of the “Right” Penicillin

After publishing his discovery of penicillin and that it affects bacteria causing meningitis, diptheria, pneumonia and scarlet fever there wasn't much interest in this discovery. Fleming struggled to cultivate and isolate the bacteria and couldn't get a chemist skilled enough to achieve this. He finally gave up his research on penicillin, but in 1940, Ernst Boris Chain and Edward Abraham from Oxford found a way to isolate the penicillin and concentrate it. Norman Heatley figured out how to purify it.With funds from the British and U.S. government, Howard Florey, head of the department, led the research to try and mass produce it. The type of fungus they were using, did not yield enough penicillin - too great quantities of the fungus was needed to barely make enough to treat people, even after they had good results in treating lab rats, their first human patient recovered slightly, but died in the end because they couldn't give him enough penicillin on time. It was a laboratory assistant, Mary Hunt, who found the right type of penicillin that made mass production possible. She arrived in the lab from the market with a cantaloupe that had a gold-colored mold. This turned out to be a fungus that had a yield of penicillin 200 times more than the species Fleming discovered and it was finally possible to provide penicillin, just in time for D-Day to save the lives of the wounded soldiers.