Trichothecene mycotoxins nivalenol

Two trichothecene mycotoxins (nivalenol and deoxynivalenol) and two related esters (3-acetyl- and 15-0-acetyl-4-deoxynivalenol) were extracted from wheat flour and separated on a Cjg coluitm (2 = 220nm). A complex 36-min 92/8 - 0/100 (9/10 water/acetonitrile)/acetonitrile gradient gave good resolution and peak shape [1100]. Standards containing 3 ppm of each compound were easily detected. 

Hedman R, Pettersson H (1997) The fates of trichothecene mycotoxins, nivalenol and fusarenon-X, in mice. Archives of animal nutrition Archiv fur Tieremahrung 50 321... 

Trichothecene mycotoxins are a group of sesquiterpenoid mycotoxins produced by fungi from the Fusarium family. There are four types Type-B such as nivalenol differs from Type-A such as diacetoxyscirpenol by the presence of the keto-group in the C8 position. Type-C has an additional epoxide group, and Type-D are macrocyclic trichothecenes. Human and animal toxicoses by these toxins have been dne to the consnmption of contaminated grain. The structure of some of the Type-A and Type-B componnds is shown in Table 14.2. 

Type B trichothecene mycotoxins consists of Nivalenol (NIV) and Deoxynivalenol (DON) which are produced by Fusarium grami-nearum. 

The trichothecene mycotoxins deoxynivalenol (vomitoxin), nivalenol and fusar-enon-X (Figure 7.2) have been measured in wheat extracts using HPLC with postcolumn photolysis (Hg vapour lamp, 2.3-3 min residence time) and ED (parallel GCEs, -I-1.10 V and -1-0.85 V vs Ag/AgCl). An ODS-modified silica analytical colunm was used with methanol-aq. sodium chloride (50 nrniol L ) (15 -I- 85) as eluent. LoDs were 1-2 ng on-column. 

Nivalenol (NIV) belongs to the B-type trichothecene mycotoxins produced by Fusarium species. The occurrence of NIV contamination is limited to certain areas around the world, such as Japan, Korea, New Zealand, and a part of Europe, where it has had adverse effects on human and animal health. This chapter focuses on the mycology, occurrence, biosynthesis, toxicology, methods of analysis, and risk assessment of NIV. 

Tanaka T, Hasegawa A, Matsuki Y, Ishii K, Ueno Y (1985) Improved methodology for the simultaneous detection of the trichothecene mycotoxins deoxynivalenol and nivalenol in cereals. Food add Contam 2 125... 

The results of studies focused on changes in the content of trichothecenes in the production of bread and other bakery products are sometimes very different, nevertheless some decrease in contamination of flour was observed, especially in fermented products, where the losses of deoxynivalenol ranged from 15 to 56%. A decrease in concentrations of deoxynivalenol (up to 40%) and some other mycotoxins (nivalenol and acetyloxynivalenols) also occurs after the addition of sulfites to the dough, as sulfites react with trichothecene mycotoxins with the addition to the C-9/C-10 double bond yielding the corresponding hydroxysulfonates. A significant reduction in the content of trichothecenes, especially... 

Tamm, Ch., and W. Breitenstein The biosynthesis of trichothecene mycotoxins. In Biosynthesis of Mycotoxins (Steyn, P. S., ed.), p. 69. New York Academic Press. 1980. Tatsuno, T. Chemical synthesis of trichothecenes. Dev. Food Sci. 4, 47 (1983). Tatsuno, T., Y. Fujimoto, and Y. Morita Toxicological research on substances from Fusarium nivale. III. Structure of nivalenol and its monoacetate. Tetrahedron Letters 1969, 2823. 

TRICHOTHECENE MYCOTOXINS. A family of structurally related poisonous substances produced by various species of fungi, especially Acremorium (Cephalosporium), Fusarium, Myrothe-cium, Stachybotrys, Trichderme, and Verticumonosporium. Tri-chothecene mycotoxins are toxic to humans because they inhibit cellular protein synthesis. Prominent examples are deoxynivalenol (sometimes referred to as vomitoxin because it induces vomiting), diacetoxyscirpenol, HT-2, nivalenol, and T-2. These five toxins gained some notoriety in the so-caUed yellow rain events in Southeast Asia because of allegations that they were associated with Soviet-inspired use of chemical weapons (CW). 

Jemmali M, Ueno Y, Ishii K, Frayssinet C, Etienne M (1978) Natural occurrence of trichothecenes, nivalenol, deoxynivalenol, T-2 toxin and zearalenone in corn. Experientia 34 1333-1334 Josephs RD, Schuhmacher R, Krska R (2001) International interlaboratory study for the determination of the Fusarium mycotoxins zearalenone and deoxynivalenol in agricultural commodities. Food Addit Contam 18 417-430... 

Contamination occurs primarily in wheat, barley, rye, and maize. Type A trichothecenes include mainly T-2 toxin, HT-2, and diacetoxyscirpenol (DAS) mycotoxins of the group B include mainly 4-deoxynivalenol (DON), commonly known as vomitoxin, and nivalenol (NIV). Toxic effects include nausea, vomiting, visual disorder, vertigo, throat irritation, and feed refusal in farm animals. The most toxic is T-2, followed by DAS and NIV, with DON being the least toxic in acute toxicity studies but the most widespread in grains worldwide and therefore the most studied. Issues related to chemical and physical data, occurrence, toxicity, absorption, distribution, and metabolism of trichothecenes are reviewed in WHO (89) and IARC (34). Physicochemical data for some selected Fusarium toxins is given by Sydenham et al. (90). The molecular structures of the main trichothecenes are shown in Fig. 9. 

Several surveys suggest that the most prevalent trichothecenes are deoxynivalenol (DON), nivalenol, 3-acetyl-DON (3-AcDON) and 15-acetyl-DON (15-AcDON), as type-B trichothecenes, and HT-2 toxin and T-2 toxin, as type-A trichothecenes. They are mainly found on maize, oats, barley, and wheat. The latter, espedally durum wheat, which is used nearly exclusively for the production of pasta, is susceptible to Fusaria infection and is often highly contaminated with DON. In European agricultural commodities type-A trichothecenes usually occur less frequently and at lower concentrations than DON. The simultaneous occurrence of DON with other Fusarium mycotoxins mainly type-B trichothecenes and zearalenone, has been reported for a variety of agricultural commodities (Gareis et al., 1989 Petterson, 1992, as cited in Krska et al., 2001). 

Methods exist for many matrix/mycotoxin combinations including patulin in apple juice using atmospheric pressure photoionization, zearalenone and its metabolites in fish tissue and porcine urine, muscle, and liver tissues using electrospray ionization, trichothecenes (T-2 toxin, HT-2 toxin, acetyl T-2 toxin, diacetoxyscirpenol, neosolaniol, and mono-acetoxyscirpenol) in grain using atmospheric pressure chemical ionization, and trichothecenes (T-2 toxin, HT-2 toxin, deoxynivalenol, nivalenol), zearalenone and its metabolites (a- and jS-zearalenol and a- and jS-zearalanol) in eggs. 

The specificity of monoclonal antibodies make it possible to develop an analytical method for a single mycotoxin, such as aflatoxin Bi in maize and groundnut meal, or aflatoxin Mj in milk and milk products. Even within chemically closely related structures such as the Fusarium trichothecenes there is very little cross-reactivity between a monoclonal raised to a single toxin such as T-2 toxin and other members of the family. Thus, a monoclonal raised against 3-acetyl-deoxynivalenol showed negligible cross-reactivity with deoxynivalenol, nivalenol, or T-2 toxin. 

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