Mycotoxins Myrothecium

Several species of Fusarium infect com, wheat, barley, and rice. Under favorable conditions they elaborate a number of different types of tetracyclic sesquiterpenoid mycotoxins that are composed of the epoxytrichothecene skeleton and an olefinic bond with different side chain substitutions (fig. 9). Based on the presence of a macrocyclic ester or ester-ether bridge between C-4 and C-15, trichothecenes are generally classified as macrocyclic (type C) or nonmacrocyclic (types A and B) (table 5). Other fungal genera producing trichothecenes are Myrothecium, Trichoderma, Trichothecium, Acremonium, Verticimonosporium and Stachybotrys. The term trichothecenes is derived from trichothecin, the first compound isolated in this group [115, 147-153]. 

Some trichothecenes, a group of mycotoxins, have macrodiolide or macrotri-olide skeletons. Trichothecenes inhibited protein synthesis by binding to the ribosomal peptidyltransferase site [141]. Roritoxins (roritoxin A, 113) are 16-membered ring macrodiolides isolated from Myrothecium roridum [142]. Verru-carin A (114) is an 18-membered ring macrotriolide produced by Myrothecium spp. [143]. 

Bean GA, Fernando T, Jarvis BB, Bruton B (1984) The Isolation and Identification of Trichothecene Mycotoxins from a Plant Pathogenic Strain of Myrothecium roridum. J Nat Prod 47 727... 

White EP, Mortimer PH, di Menna ME (1977) Chemistry of the Myrothecium Toxins. In Wyllie TD, Morehouse LG (eds.) Mycotoxic Fungi, Mycotoxins, Mycotoxicoses, Vol. 1, p. 465. Dekker, New York... 

Trichothecenes constitute a mycotoxin family produced by fungal spiecies from several genera, notably Fusarium, Stachybotrys, Myrothecium, Trichothecium, Trichoderma, Cylindrocarpon, Verticimonosporium, Acremonium, and Phomopsis. Most of the trichothecenes that have been isolated and characterized chemically are from Fusarium species that grow in the field and are distributed worldwide, representing the important pathogens of grains and other food and feed plants. Trichothecenes ap>p)ear as natural contaminants in cereal grains such as wheat, barley, oat, maize, rice, and derived products, such as bread, malt and beer (Scott, 1989). 

Trichothecenes are a group of mycotoxins produced as secondary metabolic products by various fungi of several genuses such as Fusarium, Trichoderma, Myrothecium, Trichothecium, Cephalosporium and Stachybotrys. 

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