Which antibiotic was discovered by Alexander Fleming in 1928

Antibiotics are the medicines used to kill or weaken the bacteria and also protozoa to some extent. Antibiotics can be natural, semi-synthetic, or synthetic. Penicillin in 1928 by Alexander Fleming was obtained from Penicillium Notatum . These are a group of antibacterial drugs obtained from Penicillium fungi. Penicillin fights the bacteria by attacking the cell wall forming substances (peptidoglycans). Anne Miller was the first patient who got treated using penicillin in 1942 .