Fungal growth Mycotoxins

Miller, J.O., Young, I.C. and Trenholm, H.L., Fusarium toxins in field corn. I. Parameters associated with fungal growth and production of deoxynivaneol and other mycotoxins. Can. J. Bot., 61, 3080, 1983. 

Bt corn can improve human and animal health by reducing contamination of food by mycotoxins, which are toxic chemicals produced by fungi (Wu 200 >). This is possible because Bt corn reduces insect damage that promotes fungal growth. 

Postharvest mycotoxin contamination is prevalent in most tropical countries due to a hot wet climate coupled with sub-adequate methods of harvesting, handling and storage practices, which often lead to severe fungal growth and... 

Chemical-induced liver injury is encountered in a variety of circumstances. Some natural toxins such as the peptides of Amanita phalloides, the pyrrolizidine alkaloids, the toxin of the cycad nut, and other plant toxins are hazards posed by the environment. Some mycotoxins are ingested unknowingly because of feed contamination due to climatic conditions favorable to fungal growth. Other circumstances of exposure to hepatotoxins include contamination of water supply with cyanobacterial toxins, which led to the tragic death of 60 patients in a hemodialysis clinic in Brazil in 1996 (Jochimsen et al, 1998). 

Mycotoxins are toxic substances produced by molds and fiingi, such as mushrooms. These toxic substances, known as secondary metabolites, are by-products of metabolism that are inessential to fungal growth. Although some mycotoxins can be used for medicinal purposes, most are poisonous if eaten in sufficient quantity. 

Ochratoxin A formation in apricot jam has been investigated by Ruhland et al. (1998). Apricot jam prepared conventionally was inoculated with ochratoxin A-producing A. ochraceus and P. verrucosum. Fungal growth was detected after two weeks and mycotoxin production after five weeks. Ochratoxin A contents reached up to 86.3 pg/kg for A. ochraceus and 94.6 pg/kg for P. verrMcosum-inoculated jams. Seven of twelve naturally contaminated jam samples contained 0.09-14.33 pg/kg ochratoxin A. In a market survey, Engel (2000) could not detect ochratoxin A at a concentration higher than 0.1 pg/kg in 42 commercial jam samples. 

Those which are produced by fungal microbes are linked directly to animal and human health as being the products of fungal growth. These mycotoxins are causative agents of gastrointestinal disturbances, cancer, reproductive failure, renal and nervous diseases, and abnormal tissue perfusion. 

Emerging seedlings can be killed. Undefined brown discoloration at base of tillers and lower leaf sheaths, dark brown nodes. Interior of stem and or grain shows pink fungal growth with some species. Premature ripening and whiteheads or blind ears. Some species can cause the production of mycotoxins in the grain. 

Fungal growth is influenced by a variety of plant and environmenfal tools. These factors may also influence whether a mycotoxin is produced. 

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