Cyclochlorotine (CC), also known as islanditoxin is a mycotoxin produced by the fungus Penicillium islandicum that causes liver damage and has carcinogenic properties. Japanese researchers confirmed that it was one of three strains of Penicillin fungi responsible for yellowed rice. It is listed as an IARC Group 3 carcinogen. Chemically, it is a dichlorinated cyclic peptide. Structurally, the only thing that differentiates cyclochlorotine from the plant-derived astins of Aster tataricus, is replacement of a serine with a second 2-aminobutyrate.