Fungi aflatoxins

The number of clear human epidemiologic studies is small. A total of approximately 50 compounds (c.g., benzene, vinyl chloride) and complex e.xposures (e.g., aluminum production, tobacco smoke) have sufficient data available to permit their classification as human carcinogens. The most potent human carcinogens known, the aflatoxins. are of natural origin. Their presence in food products through infestation by toxin-producing fungi constitute a serious problem in several tropical and subtropical countries. 

Geisen, R. (1996). Multiplex polymerase chain reaction for the detection of potential aflatoxin and sterigmatocystin producing fungi. Syst. Appl. Microbiol. 19, 388-392. 

Many coumarins are found in plants and a comprehensive review is available (78FOR(35)i99). Coumarin has a pleasant taste and odour and was used for flavouring until its toxic action on the liver was discovered. Among other coumarins which have toxic effects on mammals are a group called aflatoxins, e.g. aflatoxin Gi, (221), which are secondary metabolites of fungi of the Aspergillus genus. Some of these compounds have been present in animal feeds and caused deaths of the animals. In contrast, other coumarin derivatives,... 

Khoury AE1, Rizk T, Lteif R, Azouri H, Delia M-L, Lebrihi A (2006) Occurrence of Ochratoxin A- and Aflatoxin B1-Producing Fungi in Lebanese Grapes and Ochratoxin A Content in Musts and Finished Wines during 2004. J Agric Food Chem 54 8977... 

Mycotoxins of most interest are those found in human food or in the feed of domestic animals. They include the ergot alkaloids produced by Claviceps sp aflatoxins and related compounds produced by Aspergillus sp and the tricothecenes produced by several genera of fungi imperfecti, primarily Fusarium sp. 

Direct economic losses due to the presence of mycotoxin- (especially aflatoxin-)producing fungi in agricultural crops can be detected in reduced crop yields and lower quality, reduced animal performance and reproductivity... 

Liver tumors have been directly attributed to exposure to some toxicants. Androgens (associated with male sex hormones), aflatoxins (from fungi, see Chapter 19), arsenic, and thorium dioxide (administered as a suspension to many patients between 1920 and 1950 as a radioactive contrast agent for diagnostic purposes) are known to cause liver cancer. 

Dowd, P. F. (1991). Nitidulids as vectors of mycotoxin-producing fungi. In Aflatoxin in Corn New Perspectives, ed. O. Shotwell and C. R. Hurburgh, Jr. Research Bulletin 599, Iowa Agriculture and Home Economics Experiment Station. Ames, Iowa Iowa State University, pp. 335-342. 

In the first part of this chapter, we deal with insecticides including miticides and nematocides, which include very useful compounds such as avermectins and milbemycins, produced by bacteria and fungi. We list out microbial insecticides of importance and review the works mainly on the mode of action and biosynthesis of each metabolite. In the next part, major mycotoxins are listed and recent topics on them, especially on their biosynthesis, are described. Since contamination of two major mycotoxin groups, aflatoxins (AFs) and trichothecenes, in food and feed is a worldwide problem, they are treated in detail in the last part of this chapter. Recent studies on their biosynthesis, regulatory mechanism for their production, and inhibitors of their production are described. 

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