Penicillin
Group of antibiotics derived from fungi
Penicillins (P, PCN or PEN) are a group of β-lactam antibiotics originally obtained from Penicillium moulds, principally P. chrysogenum and P. rubens. Eight species of Penicillium, in the section Chrysogena, produce penicillins. Most penicillins in clinical use are synthesised by P. chrysogenum using deep tank fermentation and then purified.
From Wikipedia, under CC BY-SA. More on occurri.