Penicillin was discovered by Alexander Fleming, a microbiologist, in the year 1927. He was conducting experiments in search of novel antibacterial agents that would be effective in healing wounds. While carrying out these experiments, he observed that a culture of Staphylococcus aureus on a Petri dish had been contaminated by mold. He observed clear areas (zones) around the mold-no bacterial colonies. Apparently, the Staphylococcus cells near the mold were inhibited or killed by the mold. Further studies revealed that this mold was of the genus Penicillium that produced a potent substance against Staphylococci and hence a very attractive chemotherapeutic agent. Fleming named it Penicillin.