Alternariol was first reported by Raistrick and colleagues in 1953. Alternariol and its monomethyl ether analogue occur in mycelium of Alternaria tenuis responsible for alternaria cone disorder in hops and fruit spot on papaya (Carica papaya) and Passiflora spp. Alternariol forms reactive oxygen species and interacts with DNA topoisomerase, generating single- and double-strand DNA beaks. Alternariol represses immune responses in an inflamed environment, possibly leading to increased disease susceptibility, and may increase autophagic activity and induce senescence in macrophages.