Submitted to: Poisonous Plants Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 10/1/2003
Publication Date: 2/1/2004
Citation: Bryden, W.L., Lowe, M., Amba, T.M., Abbas, H.K. 2004. Fusarachromanone and wortmannin: novel fusarium toxins. In: Acamovic, T., Stewart, C.S., Pennycott, T.W. editors. Poisonous Plants Symposium Proceedings. Wallingford, Oxon. p. 63-69.
Technical Abstract: Fusarachromanone and wortmannin are novel Fusarium mycotoxins which perturb distinct physiological functions. Despite many years of study and the delineation of the factors which influence the incidence of tibial dyschondroplasia (TD), an abnormal cartilage formation in broiler chickens, the direct cause of TD remains unknown. A reproducible model of TD has been ndeveloped with fusarchromanone. Using this experimental model it was unequivocally demonstrated that genetic predisposition is the major factor in determining the incidence of the disease. Reducing growth rate was shown to reduce the incidence of TD but of the nutrients examined only dietary vitamin D varied the incidence of the disease. The mechanism of the interaction remains to be elucidated. Wortmannin produces haemorrhages in various organs of the body and was initially called haemorraghic factor or H-1 when it was isolated from F. oxysporum and F. sambucinum. Based on the clinical signs of haemorrhage it has been postulated that wortmannin was responsible for a mycotoxicosis of humans in the USSR in the 1940's that is alimentary toxin aleukia. It has also been suggested that the toxin is involved in the aetiology of unexplained haemorrhagic syndromes in farm animals. Our understanding of insulin action and glucose homeostasis has been assisted by the use of wortmannin as a metabolic inhibitor. In addition to the clinical signs noted above, both fusarachromanone and wortmannin have been shown to be immunosuppressive. There is a need for more information on the factors determining the production of these toxins and detailed surveys of their natural occurrence.