Rugulosin is an intense yellow pigment produced by some fungal species of Penicillium, Aspergillus and the fungal symbiotants of some lichens. Rugulosin shows antibacterial and insecticidal activity and has found application as a bioinsecticide, notably as the active secondary metabolite in endophytic fungi of seedlings.
Rugulosin (+ form) is an inhibitor of RNA Polymerase and RNase.