Gyromitrin
Gyromitrin is a toxin and carcinogen present in several members of the fungal genus Gyromitra, G. esculenta. It is unstable and is easily hydrolyzed to the toxic compound monomethylhydrazine, a component of some rocket fuels. Monomethylhydrazine acts on the central nervous system and interferes with the normal use and function of vitamin B6. Poisoning results in nausea, stomach cramps, and diarrhea, while severe poisoning can result in convulsions, jaundice, or even coma or death. Exposure to monomethylhydrazine has been shown to be carcinogenic in small mammals.