Trichothecene mycotoxins deoxynivalenol

Shima, J. et al., Novel detoxification of the trichothecene mycotoxin deoxynivalenol by a soil bacterium isolated by enrichment culture, Appl. Env. Microbiol., 63, 3825, 1997. 

A further method of determining the trichothecene mycotoxin deoxynivalenol in corn is based on DPP [33] and also on GC. 

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. 

Maresca M. From the gut to the brain journey and pathophysiological effects of the food-associated trichothecene mycotoxin deoxynivalenoL Toxins. 2013 5 784-820. 

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... 

Of four basic trichothecene groups (A, B, C and D), types A and B represent the most important mycotoxins. Type A includes the T-2 toxin that can suppress the immune system and can cause damage to bone marrow. The T-2 toxin is about 14 times more toxic than the most widespread Fusarium-based type B mycotoxin, deoxynivalenol (DON), previously called vomitoxin. DON is a... 

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... 

FIGURE 26.1. Chemical structure of trichothecene mycotoxins from group A, T-2 toxin group B, deoxynivalenol (DON) and group D (satratoxin H). From Haschek et al. (2002). 

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

A GC/MS technique has been developed for the detection of trichothecene mycotoxins. The technique has been used to quantitate the trichothecene deoxynivalenol in corn, wheat and mixed feeds. The trichothecenes are derivatized with heptafluorobutyrylimidazole and the derivatives are separated by gas chromatography. 

Casale, W. L. Inhibition of protein synthesis in maize and wheat by trichothecene mycotoxins and hybridoma-based enzyme immunoassay for deoxynivalenol. 168 pp. Avail. Univ. Microfilms Int., Order No. DA8722822. From Diss. Abstr. Int B 1988,48(8), 2167. 1987. 

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). 

Post-column photolysis to give electroactive products has been used in the measurement of trichothecene mycotoxins, such as deoxynivalenol (vomitoxin) in... 

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. 

Sulyok et al. [113] reported the first validated method for the determination of 39 mycotoxins in wheat and maize by liquid chromatography with electrospray ionization-triple quadmpole mass spectrometry (LC/ESI-MS/MS) without the need for any cleanup. The 39 analytes included A and B trichothecenes (including deoxynivalenol-3-glucoside), ZEN and related derivatives, fumonisins, enniatins, ergot alkaloids, ochratoxins, aflatoxins, and moniliformin, and six trichothecene mycotoxins (NIV, DON, fusarenon-X, 15-acetyldeoxynivalenol, 3-acetyldeoxynivalenol, and T-2 toxin). 

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... 

Deoxynivalenol, also known as DON or vomitoxin, is a trichothecene mycotoxin that affects brain neurochemistry (e.g., dopamine and 5-hydroxyindolacetic acid), leading to nausea and appetite suppression. Feed refusal or decreased feed intake occurs through a learned response known as "taste aversion."... 

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). 

Some microorganisms are also able to transform trichothecenes into less toxic compounds. For example, rumenal bacteria, bacteria from the large intestine of chickens, and bacterial populations from soil samples, were capable of transforming deoxynivalenol into 3-acetyldeoxynivalenol or 3-keto-4-deoxynivalenol (Binder et ah, 2000 Swanson et ah, 1987 He et ah, 1993 Shima et ah, 1997). Therefore, it seems likely that the development of wheat crops with the capability of eliminating this mycotoxin or bio-treatments could possibly be developed as a feasible strategy. 

Knoll, A., Niessen, L., and Vogel, R. F. (2000). Application of a PCR protocol for the diagnosis of trichothecene producing Fusarium species in deoxynivalenol contaminated wheat. Mycotoxin Res. 16A, 240-243. 

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. 

In our research, we proposed a post amplification analytical method to detect F. culmorum, a pathogen causing foot rot and head blight diseases in cereals, and can produce mycotoxins such as zearalenone, deoxynivalenol, and other trichothecenes that can enter the food chain. The early identification of this fungal pathogen is therefore recommended in order to avoid crop losses and protect consumer health... 

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. 

In recent years the need for more information about the type A trichothecenes has been emphasised, not only with regard to their toxicity (this is greater than that of deoxynivalenol), but also due to the increasing trend of incidence in European cereals. Mycotoxins T-2 and HT-2 (a product of T-2 deacetylation) are found mainly in oats, where their amounts may be up to 1000 p.g/kg, but the annual variabUity of contamination is considerable. The only way to reduce the level of type A trichothecenes in foods and feeds containing oats is the removal of bran from grains, as bran may contain 75 90% of the total amount of these mycotoxins. 

FIGURE 6.4 Chemical structure of most common grain mycotoxins. (a) Zeralenone. (b) Ochratoxin A or OTA. (c) Fumonisin. (d) Trichothecenes or T-2. (e) Deoxynivalenol or DON. (f) Ergotamine. 

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