3721 Deoxynivalenol Deoxynivalenol is found in cereals and cereal products. Deoxynivalenol is produced by Fusarium graminearum and Fusarium roseum, responsible for headblight in cereals Vomitoxin, also known as deoxynivalenol (DON), is a type B trichothecene, an epoxy-sesquiterpeneoid. This mycotoxin occurs predominantly in grains such as wheat, barley, oats, rye, and maize, and less often in rice, sorghum, and triticale. The occurrence of deoxynivalenol is associated primarily with Fusarium graminearum (Gibberella zeae) and F. culmorum, both of which are important plant pathogens which cause Fusarium head blight in wheat and Gibberella ear rot in maize. Deoxynivalenol is a direct relationship between the incidence of Fusarium head blight and contamination of wheat with deoxynivalenol has been established. The incidence of Fusarium head blight is strongly associated with moisture at the time of flowering (anthesis), and the timing of rainfall, rather than the amount, is the most critical factor. Furthermore, deoxynivalenol contents are significantly affected by the susceptibility of cultivars towards Fusarium species, previous crop, tillage practices, and fungicide use Deoxynivalenol belongs to the family of Trichothecenes. These are sesquiterpene mycotoxins structurally characterized by the presence of an epoxide ring and a benzoyran derivative with a variant number of hydroxyl, acetly, or other substituents [1]. (Reference: [1] http://www.inchem.org/documents/ehc/ehc/ehc105.htm). 51481-10-8 430147 C15H20O6 White crystalline solid. 151 - 153°C Oral, dermal, inhalation, and parenteral (contaminated drugs). (A3101) Unlike many other mycotoxins, trichothecenes do not require metabolic activation to exert their biological activity, instead directly reacting with cellular components. Trichothecenes are cytotoxic to most eukaryotic cells due to their powerful ability to inhibit protein synthesis. They do this by freely moving across the plasma membrane and binding specifically to ribosomes with high-affinity. Specifically, they interfere with the active site of peptidyl transferase at the 3'-end of large 28S ribosomal RNA and inhibit the initiation, elongation or termination step of protein synthesis, as well as cause polyribosomal disaggregation. Protein synthesis is an essential function in all tissues, but tissues where cells are actively and rapidly growing and dividing are very susceptible to the toxins. Additionally, binding to ribosomes is thought to activate proteins in downstream signalling events related to immune response and apoptosis, such as mitogen-activated protein kinases. This is known as ribotoxic stress response. Trichothecenes may also induce some alterations in membrane structure, leading to increased lipid peroxidation and inhibition of electron transport activity in the mitochondria. They can further induce apoptosis through generation of reactive oxygen species. Further secondary effects of trichothecenes include inhibition of RNA and DNA synthesis, and also inhibition of mitosis. (L1948, L1949, A2962, A2963, A2964, A2980) Trichothecenes are lipophilic and thus easily absorbed through the skin, gut, and pulmonary mucosa. They are metabolized mainly by cytochrome P-450 and trichothecene-specific carboxylesterase activity in the liver, although other tissues such as the kidney, spleen, and intestine also show some metabolic activity. Trichothecenes are metabolically transformed to less toxic metabolites by such reactions as hydrolysis, hydroxylation, de-epoxidation, and glucuronidation. Deoxynivalenol is metabolized mainly to the de-epoxy metabolite. Metabolites are excreted in the urine and feces. (L1910, L1949, A738) LD50: 70 mg/kg (Intraperitoneal, Mouse) (T312) LD50: 46 mg/kg (Oral, Mouse) (T313) LD50: 43 mg/kg (Subcutaneous, Mouse) (L1949) 3, not classifiable as to its carcinogenicity to humans. (L135) Vomitoxin, also known as deoxynivalenol (DON), is a type B trichothecene, an epoxy-sesquiterpeneoid. Trichothecenes are a very large family of chemically related mycotoxins produced by various species of Fusarium, Myrothecium, Trichoderma, Trichothecium, Cephalosporium, Verticimonosporium, and Stachybotrys. Vomitoxin occurs predominantly in grains such as wheat, barley, oats, rye, and maize, and less often in rice, sorghum, and triticale. The occurrence of deoxynivalenol is associated primarily with Fusarium graminearum (Gibberella zeae) and F. culmorum, both of which are important plant pathogens which cause Fusarium head blight in wheat and Gibberella ear rot in maize. (L1948, L1951) Trichothecenes have multiorgan effects including anoerxia and weight loss, growth retardation, nervous disorders, cardiovascular alterations, immunodepression, hemostatic derangements, skin toxicity, decreased reproductive capacity, bone marrow damage, and alimentary toxic aleukia. (L1948, L1949, A2964) After direct dermal application or oral ingestion, the trichothecene mycotoxins can cause rapid irritation to the skin or intestinal mucosa, including skin irritation, burning and itching, rash or blisters, and bleeding. Eye contact can cause tearing, eye pain, conjunctivitis, burning sensations about the eyes, and blurred vision for up to 1 week. Symptoms also include nausea, vomiting, fatigue, dyspnea, and acute vascular effects leading to hypotension and shock. (L1948, L1949) There are no known antidotes to trichothecene mycotoxins. Treatments are directed at supporting hemopoietic abnormalities, gastrointestinal damage, and skin damage. Administer charcoal as a slurry in case of acute oral exposure. In case of inhalation: Move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with inhaled beta2 agonist and oral or parenteral corticosteroids. In case of eye exposure, Irrigate exposed eyes with copious amounts of room temperature water for at least 15 minutes. In case of dermal exposure, Remove contaminated clothing and wash exposed area thoroughly with soap and water. (A704) 2010-04-14T00:54:38Z 2014-12-24T20:26:19Z http://en.wikipedia.org/wiki/Deoxynivalenol C09747 true CC1=CC2OC3C(O)CC(C)(C33CO3)C2(CO)C(O)C1=O C15H20O6 InChI=1/C15H20O6/c1-7-3-9-14(5-16,11(19)10(7)18)13(2)4-8(17)12(21-9)15(13)6-20-15/h3,8-9,11-12,16-17,19H,4-6H2,1-2H3 InChIKey=LINOMUASTDIRTM-UHFFFAOYNA-N 296.3157 296.125988372 Exogenous Solid HMDB36156 380420