Video:Alexander Fleming's Discovery of Penicillin

Transcript:Alexander Fleming's Discovery of Penicillin

Hi, I am William Morgan with About.com, and today I'm going to talk about Alexander Fleming's discovery of penicillin.

Initial Discovery of Penicillin

The popular antibiotic penicillin originated from a penicillium mold that could kill bacteria. Alexander Fleming, a Scottish biologist and pharmacologist, first discovered penicillin in 1928 some time in September. The discovery was made upon examination of a petri dish he had set aside prior to vacation at his country house with his family. Fleming had picked up a dish to demonstrate to a friend the horrid amount of work he had to do to. He then noticed that a mold had grown on it in his absence which had killed the staphylococcus aureus that had been growing on the dish.

Circumstances for Fleming's Discovery of Penicillin

Ever since his discovery of lysozyme, a natural substance in nasal mucus and tears that cleans away bacteria, Fleming had been pursuing the idea that there could be a substance that killed bacteria without adversely affecting the human body. After several weeks growing mold, he and mycologist C. J . La Touche determined the mold to be of the penicillium variety, thus the name penicillin. It is likely the mold floated upstairs from La Touche's room where he had been collecting mold samples for John Freeman, who was researching asthma.

Dead End for Alexander Fleming

Running numerous tests, Alexander found that the mold killed a large number of bacteria and was non toxic. Despite the mold's antibacterial qualities, Fleming wasn't able to push the matter further. He wasn't a chemist and couldn't isolate the active antibacterial element or keep the element active long enough for human use. In 1929 he wrote a paper on his discovery that didn't gather any scientific interest.

Vindication for Alexander Fleming

It wasn't until twelve years later that Australian pharmacologist and pathologist, Howard Florey and German-born, British bio-chemist, Ernst Chain, who had been conducting experiments on promising projects in bacteriology, came across penicillin and, using modern chemical techniques, produced a brown powder that could keep its antibacterial properties longer than a few days. Mass production skyrocketed. It was the second year of World War II and the antibacterial was extremely valuable for cleaning wounds. Penicillin saved the lives of many veterans who otherwise would have died from infection. Penicillin also treated diphtheria, gangrene, pneumonia, syphilis and tuberculosis. Flemming, Florey, and Chain were all knighted in 1944 and given the 1945 Nobel Prize in physiology or medicine.

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