Alexander Fleming — "My only merit is that I did not discard the cultures at an early stage."

"The mould was very interesting. I cultured it and found it produced a powerful antibacterial substance. It was very effective against staphylococci and other Gram-positive pathogenic bacteria."

"We must be careful not to create a race of penicillin-resistant superbugs."

"It is not difficult to make microbes resistant to penicillin in the laboratory by exposing them to concentrations not sufficient to kill them, and the same thing has occasionally happened in the body."

"It is the common lot of discoverers to be misunderstood."

"The story of penicillin has a certain romantic appeal, and I think that may be one of the reasons it has attracted so much attention. But the real story is much more prosaic."