T-2-Tetraol

Chatterjee, K. Visconti, A. Mirocha, C. J. Deepoxy T-2 Tetraol A Metabolite of T-2 Toxin Found in Cow Urine. J. Agric. Food Chem., submitted for publication, 2004. 

The strucure-activity response is even more subtly expressed in the etiolated wheat coleoptile (Triticum aestivum L. Wakeland) that has been described in detail elsewhere (13) Subtle modifications in structure cause marked changes in the inhibitory responses induced (Table I). With the exception of 15-acetoxy-T- 2-tetraol, neosolaniol and isoneosolaniol which are inactive at lO M (Fig. 2l, all of the trichothecenes so far tested are active at 10" M. A further one-third are active at 10"°M and the most potent, which are active at 10" M, are verrucarins A and J, and trichoverrin B, Neosolaniol, which inhibits 100% at 10" and 61% at 10" M has an acetate at C15 while isonesolaniol, which has an hydroxyl group at C15 inhibits coleoptiles 80 and 51% at 10" and 10"3, respectively. 

NEOSOLANIOL MONOACETATE 3 -HYDROXY-HT-2 TOXIN 15-ACETOXY-T-2 TETRAOL 3 -HYDROXY-T-2 TRIOL HT-2 TOXIN T-2 TOXIN RORIDIN A ISORORIDIN E BACCHARINOL B4 VERRUCARIN A VERRUCARIN J TRICHOVERRIN B NEOSOLANIOL ISONEOSOLANIOL... 

There are a large number of different trichothecenes and ideally their analysis requires confirmation using GC-MS and analysis of the macrocyclic trichothecenes, which includes the verrucarins, ror-idins, and satratoxins, requires considerable experience and a specialized laboratory. However, well-established methods are available for individual trichothecenes of particular importance, such as T-2 toxin, diacetoxyscirpenol, deoxynivalenol, and neosolaniol. The large niunber of Fusarium trichothecenes are acylated derivatives of a much smaller niunber of parent alcohols, such as T-2 tetraol, scirpentriol, deoxynivalenol, and nivalenol, so another approach to their analysis is to hydrolyze the possibly complex mixture of trichothecenes to the parent alcohols and analyze these as their trimethylsilyl ethers. However, when this is done, there is often a poor correlation between total trichothecene content and observed toxicity, reflecting the large differences in the toxicity of different acyl derivatives even of the same parent alcohol. 

T-2 toxin is believed to undergo selective C-4 deacetylation by hepatic microsomal carboxyesterase to yield HT-2 toxin (Ohta et al., 1977 Otta et al., 1978). Further metabolism by the same enzyme leads to the stepwise conversion of HT-2 toxin to the more polar metabolites 4-deactylneosolaniol and T-2 tetraol (Yoshizawa et al., 1980a). The lack of effect of T-2 toxin on the activity of heaptic esterase may be due to the non-specific nature of this enzyme. The low dose of toxin may not have been enough to cause substrate induction of the enzyme. The lack of effect of additives on the activity of hepatic esterase adds support to the concept that they do not alleviate T-2 toxicosis by promoting catabolism of the toxin. 

Schappert, K.T., Koshinsky, H.A. and Khachatourians, G.G. 1986. Growth inhibition of yeast by T-2, HT-2, T-2 triol, T-2 tetraol, diacetoxyscirpenol, verrucarol, verrucarin A and roridin A mycotoxins. J. Amer. Coll. Toxicol. 5 181-187. 

T-2-Tetraol 3a,4)5,8a, 15-Tetrahydroxy-12,13-epoxytrichothec-9-ene C15H22O6 Mirocha and Pathre (1973)... 

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