Trichothecene mycotoxins toxicology

Kalantary makes a general outline on mycotoxins and fusarium toxins as environmental toxicants, their mycotoxicosis, the historical background of trichothecene mycotoxins and toxicological aspects. 

Many mycotoxins have been reported on the basis of various toxicological experiments. Some have been indicated as etiological agents of certain human and animal mycotoxicoses, such.as trichothecene mycotoxins. Fig. 1 shows the general structure and numbering system of trichothecene mycotoxins. 

There are many reports on toxicological effects of trichothecene mycotox-ins to animal and livestock. In general,acute toxicity of trichothecene mycotoxins is highest in Type D compounds such as Verrucarin A and Roridin A, followed by Type A, such as T-2 toxin and Type B trichothecene mycotoxins. Table 3 shows the LD50 of trichothecene mycotoxins. 

In this article the general outline on mycotoxins and fusarium toxins as environmental toxicants their mycotoxicosis, the historical backgrounds of trichothecene mycotoxins chemistry and toxicological aspects were described. In order to protect the environment as well as human from these toxins and also to find a potential antidote for these toxins it is worthy to work in this area of research. 

Data sources (1) Ueno Y. Trichothecene mycotoxins Mycology, chemistry, and toxicology. Adv Nut Res. 1989 3 301-353. (2) Wannemacher RW Jr, Bunner DL, Neufeld HA. Toxicity of trichothecenes and other related mycotoxins in laboratory animals. In Smith JE, Henderson RS, eds. Mycotoxins and Animal Foods. Boca Raton, Fla CRC Press 1991 499-552. (3) Sharma RP, Kim Y-W. Trichothecenes. In Sharma RP, Salunkhe DK, eds. Mycotoxins and Phytoalexins. Boca Raton, Fla CRC Press 1991 339-359. (4) Jarvis BB. Macrocyclic trichothecenes. In Sharma RP, Salunkhe DK, eds. Mycotoxins and Phytoalexins. Boca Raton, Fla CRC Press 1991 361-421. 

Four hours after swine received intravenous tritium-labeled T-2 toxin, glucuronide conjugates represented 63% of the metabolic residues in urine, and 77% in bile.63 The formation of glucuronide conjugates generally results in the elimination of toxicological activity of xenobiotics, which in certain species could represent a major route of detoxification of trichothecene mycotoxins. 

Ueno Y. Trichothecene mycotoxins Mycology, chemistry, and toxicology. Adv Nutr Res. 1989 3 301-353. 

Committee on Protection Against Mycotoxins, Board on Toxicology and Environmental Health Hazards, Commission on Life Sciences, National Research Council. Protection Against Trichothecene Mycotoxins. Washington, DC National Academy Press 1983. 

Trichothecene mycotoxins are secondary metabolites of various fungal species. Structures of some trichothecene mycotoxins of interest to the US ARMY are given in Figure 1. Several methods have been reported for the analysis of these toxins (1-11, 15). Of these, mass spectrometry techniques are both sensitive and definitive when applied to toxicologic and environmental samples. With current technology, the most sensitive and qualitatively definitive analytical technique for the determination of these toxins is derivatization with an electron deficient moiety followed by analysis with negative ion chemical ionization gas chromatography-mass spectrometry (NICI-GC/HS). 

Ueno, Y. (1980). Trichothecene mycotoxins mycology, chemistry, and toxicology. In "Advances in Nutritional Research", H.H. Draper, Ed., Vol. 3, pp. 301-353, Plenum Press, New York. 

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. 

Because NIV is a minor mycotoxin in the world, information for risk assessment is very poor. Of course, European countries and Japan have recognized the threat posed by NIV to human health and have started to evaluate this risk. In the risk assessment of NIV, it is recommended to take into account the effect of co-contamination with other trichothecene mycotoxins, namely, DON. As further studies, combination toxicology studies of NIV and DON are needed. 

Ueno, Y., Nakajima, N., Sakai, K., Ishii, K., Sato, N. and Shimada, N. 1973. Comparative toxicology of trichothecene mycotoxins inhibition of protein synthesis in animal cells. J. Biochem. 74 285-296. 

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. 

Ueno Y Trichothecenes Chemical, Biological, and Toxicological aspects. Amsterdam, Elsevier, 1983. Vesonder RF, Golinski P in Chelkowski J (ed) Fusarium Mycotoxins, Taxonomy, and Pathogenicity. New York, Elsevier, 1989, pp 1-39. 

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