Toxins mycotoxins

Trichothecene mycotoxin Toxin produced by fungal molds it inhibits protein synthesis, impairs DNA synthesis, and interferes with cell membrane structure and function. 

McCormick SP, Stanley AM, Stover AN, Alexander NJ (2011) Trichothecenes From Simple to Complex Mycotoxins. Toxins 3 802... 

See FOOD AND NUTRITIONAL ANALYSIS Mycotoxins. TOXINS Mycotoxins... 

Aflatoxins are the most feared of the mycotoxins-toxin-pro-ducing molds. There are four main aflatoxins B B2, G and Gj, of which B, is the most common and the most toxic. A high incidence of cancer, especially liver cancer, is associated with aflatoxin. 

This same experimental approach can be used to determine the appHcabiUty of the aDAS—AP to a competitive assay for DAS. As shown in Eigure 6, increasing amounts of free DAS were used to define the 50% inhibition level (ID q) of DAS for binding of two aDAS—AP conjugates to immobilized DAS. This approach was also used to determine the sensitivity of an EIA, as well as the specificity of the assay, as shown in Table 2. Increasing amounts of trichothecene mycotoxins closely related to DAS were added to microtiter plate wells containing a constant amount of prereacted DAS—aDAS—AP. After 30 min, excess toxin and any free toxin—aDAS—AP were washed out, and substrate was added. Quantification of the color produced was directly related to the abihty of the added toxin to displace aDAS—AP from the immobilized DAS, which is an indication that the aDAS also has an avidity for that toxin. 

Assessment of whether a chemical has the potential to cause adverse effects in humans arises usually from direct observation of an effect in animals or humans, such as the acute poisoning episodes that have occurred when potatoes contain high levels of glycoalkaloids. Epidemiological studies have also been used to infer a possible relationship between intake of a particular type of food, or constituent of that food, and the potential to cause an adverse effect. Such observations led to the characterisation of the aflatoxins as human carcinogens. However, natural toxic substances that occur in plant foods have often been identified through observations in animals, particularly farm animals. It was observations of adverse effects in farm animals that led to the further characterisation of the phytoestrogens and the mycotoxins. In other instances, the concern arises from the chemical similarity to other known toxins. 

In order to identify chemically the so-caUed monascidin A discussed by some Chinese scientists in their papers as a component suitable for the preservation of food, it was isolated and chemical investigations using mass spectrometry and NMR were undertaken. Monascidin A was characterized as citrinin which is known to be a mycotoxin responsible for nephropathies. Thus, in order to avoid the production of this toxin, various strains were screened in order to see whether all were toxino-genic and it was shown that among the species of Monascus available in pubhc collections, non-toxinogenic strains were obtainable. 

Of four basic trichothecene groups (A, B, C and D), types A and B represent the most important mycotoxins. Type A includes the T-2 toxin that can suppress the immune system and can cause damage to bone marrow. The T-2 toxin is about 14 times more toxic than the most widespread Fusarium-based type B mycotoxin, deoxynivalenol (DON), previously called vomitoxin. DON is a... 

D Mello J P F (2003), Mycotoxins in cereal grains, nuts and other plant products , Food Safety Contaminants and Toxins, CAB International, Wallingford, 65-90. 

Toxins are primarily hazardous through inhalation, ingestion, and broken, abraded, or lacerated skin (e.g., penetration of skin by debris). A small number of toxins, such as the mycotoxins, produce skin lesions and systemic illness through skin and eye exposure. Toxins may also be dissolved in select solvents and delivered as dilute solutions that pose a percutaneous hazard. 

A case in which the toxin or appropriate metabolite is detected in urine, serum, or plasma, or detection of the specific toxin in environmental samples unless there could be a local source of the toxin (e.g., the molds that produce mycotoxins have been found in some residential and industrial settings, and the toxins have been implicated in some cases of "sick building" syndrome). 

Jemmali M, Ueno Y, Ishii K, Frayssinet C, Etienne M (1978) Natural occurrence of trichothecenes, nivalenol, deoxynivalenol, T-2 toxin and zearalenone in corn. Experientia 34 1333-1334 Josephs RD, Schuhmacher R, Krska R (2001) International interlaboratory study for the determination of the Fusarium mycotoxins zearalenone and deoxynivalenol in agricultural commodities. Food Addit Contam 18 417-430... 

Lawrence JF, Scott PM (2000) HPLC methods for the determination of mycotoxins and phyco-toxins. Tech Instrum Anal Chem 21 413—456... 

Malekinejad H, Schoevers EJ, Daemen IJ, Zijlstra C, Colenbrander B, Fink-Gremmels F, Roelen BAJ (2007) Exposure of oocytes to the Fusarium toxins zearalenone and deoxynivalenol causes aneuploidy and abnormal embryo development in pigs. Biol Reprod 77 840-847 Maragos CM, Appell MD (2007) Capillary electrophoresis of the mycotoxin zearalenone using cyclodextrin-enhanced fluorescence. J Chromatogr A 1143 252-257... 

Defensive Measures Good personal hygiene, physical conditioning, wearing protective mask, and practicing good sanitation. Mycotoxin-induced disease is not contagious, but the stability of this toxin in the environment is quite persistent. 

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