As everyone knows, it was Alexander Fleming who discovered penicillin, but he never actually tried to make an antibiotic out of it. It wasn't until over a decade later that Howard Florey and Ernst Chain, after reading Fleming's paper on the antibacterial properties of the mold, started work on developing the antibiotic and used it on their first patient who had a severe facial infection involving Streptococci and Staphylococci. Within just a day of being given the penicillin, the patient started to make a recovery.
He shared the Nobel Prize in Physiology or Medicine in 1945 with Ernst Chain and Alexander Fleming for his role in the development of penicillin. Their work is estimated to have saved over 200,000,000 lives over the years.
Source:
Howard Florey on Wikipedia (https://en.wikipedia.org/wiki/Howard_Florey)