Sterigmatocystin is a mycotoxin that has been found in Aspergillus. It is lethal to rats (LD50 = 60 mg/kg) and chick embryos (LD50s = 5-7 μg/embryo). Sterigmatocystin (100 and 1,000 ppb in drinking water) induces gastritis, as well as intestinal polyp formation and metaplasia in aged Mongolian gerbils. It induces formation of lung and liver adenomas and malignant lymphomas in newborn mice.
Sterigmatocystin is a carcinogenic mycotoxin that is struturally related to Aflatoxin. Sterigmatocystin has been shown to inhibit RNA synthesis in rat liver nuclei.
Sterigmatocystin is a xanthone produced by several species of Aspergillus, isolated by a number of research groups in the 1950s as a mycotoxin associated with food and grain contamination. Sterigmatocystin is structurally related to the aflatoxins and, while it is considered to be mutagenic, teratogenic and carcinogenic, it is less widespread and potent than the aflatoxins. Sterigmatocystin, in the presence of microsomes, covalently binds to DNA. It uncouples oxidative phosphorylation but, unlike the aflatoxins, does not induce mitochondrial swelling or hinder Ca2+-induced swelling of mitochondria. Sterigmatocystin also inhibits acyl-CoA:cholesterol acyltransferase (ACAT) with selectivity for the ACAT2 isoenzyme.
ChEBI: An organic heteropentacyclic compound whose skeleton comprises a xanthene ring system ortho-fused to a dihydrofuranofuran moiety. The parent of the class of sterigmatocystins.
Possible carcinogen; tumorigen; poison;
mutagen; causes necrosis of the liver and kidney,
and an inhibitory effect on orotic acid incorporation
into nuclear RNA.
Initiates lung and liver tumors under experimental conditions.
Confirmed carcinogen with experimental carcinogenic and tumorigenic data. Poison by ingestion and intraperitoneal routes. Human mutation data reported. When heated to decomposition it emits acrid smoke and irritating fumes.
It crystallises from amyl acetate, Me2CO or EtOH and sublimes in vacuo. It has UV max at 208, 235, 249 and 329nm (log 4.28, 4.39, 4.44 and 4.12). [UV: Bullock et al. J Chem Soc 4179, 1962, UV, IR: Holker & Mulheirn J Chem Soc, Chem Commun 1576, 1576 1968, Birkinshaw & Hammady Biochem J 65 162 1957.] This mycotoxin induces bone marrow changes in mice [Curry et al. Mutation Res 137 111 1984]. [Beilstein 19/10 V 575.]
