Estrogenic mycotoxin

Because estrogenic mycotoxins usually occur at microgram per kilogram (pg/kg) levels there is special interest in analytical procedures for reliable detection of zearalenone and its metabolites between 10 and 100 pg/kg. In response to the risk of a great economic loss to the industry and the threat to human health as a result of exposure to zearalenone, several methods have been developed for the quantification of zearalenone and its metabolites in different foods, feeds, animal tissues, blood and urine. Detailed reviews have been given by Steyn et al. 1991 Betina 1993 Frisvad and Thrane 1993 Scott 1993 Steyn 1995 and Lawrence and Scott 2000. The determination of zearalenone in cereals can be divided into five steps grinding of the sample, extraction of the sample, clean-up, separation and detection. 

Krska R (1998) Performance of modern sample preparation technique in the analysis of Fusarium mycotoxins in cereals. J Chromatogr A 815 49-57 Krska R, Josephs R (2001) The state-of-the-art in the analysis of estrogenic mycotoxins in cereals. J Anal Chem 369 469-476... 

Zearalenone is an estrogenic mycotoxin that usually causes toxicity in swine that consume contaminated corn. Prepubertal swine are mostly affected. Affected females show swelling of the vulva and excessive straining, which may cause vaginal prolapses. In male animals, zearalenone will cause decreased libido. There is no effective treatment apart from withdrawing the feed containing the mycotoxin. 

Recently, much concern has been expressed about the effect of synthetic chemicals that have estrogen-like effects. We have touched on this lightly in previous chapters and will revisit it in Chapter 7. Zearalenone is an estrogenic mycotoxin produced by a number of species of Fusarium mold. It has caused a number of abnormalities in the reproductive system in animals and possi-... 

The answer is 5 [III B 4 e Table 12-11. Zearalenone is the only estrogenic mycotoxin among the choices given. As an estrogen, zearalenone can provide negative feedback to prevent the release of gonadotropin. 

ZEA is an estrogenic mycotoxin produced by numerous species of Fusarium, mainly F. reticulatum which frequently colonise eereal crops worldwide (Domer, 1998). It has been reported that ingestion of mycotoxins of the Fusarium genus via contaminated cereals may lead to fertility disturbances and other reproductive pathologies (Minervini, Dell Aquila, Maritato, Minoia Visconti, 2001). 

Shier WT, Shier AC, Xie W and Mirocha CJ. 2001. Structure-activity relationships for human estrogenic activity in zearalenone mycotoxins. Toxicon 39 (9) 1435—1438. 

Variations in the use pattern of industrial and agricultural chemicals throughout the world preclude standardization by international organizations such as OECD. Despite this fact, common dietary constituents, which are known to influence toxicity are antioxidants, unsaturated fatty acids, and selenium. These must be present in interfering concentrations. The potential impact of several common dietary contaminants on chronic toxicity assessment therefore, necessitates that special attention be given to their presence. In this respect, substances of concern include pesticide residues, chlorinated and polycyclic aromatic hydrocarbons, estrogens, heavy metals, nitrosamines, and mycotoxins. 

Mycotoxins may include butanol, estrogenic compounds (e.g., zearalenone), heptanone, lactones, lactams (patulin), stachybotrylactones, stachybotry-lactams, 2-pentylfuran, 2-hexanone, 2-methyl-1-propanol, 3-methylfuran, 2-methylisoborneol, 3-methyl-2-butanol, and macrocyclic trichothecenes (Satratoxins F, G. and H, Roridine, Verrucarinj, and Trichoverrols). 

Natural products Selected vitamins, antibiotics, vinca alkaloids, estrogen, plant alkaloids, mycotoxins ... 

Zearalenone (9.13) is a mycotoxin with estrogenic activity and suspected... 

According to their structural diversity, the RALs exhibit a variety of biological activities. Although it is classed as a mycotoxin, zearalenone (479) is barely toxic (9). Its anabolic and uterotrophic traits 338) are the result of its interaction with estrogenic receptors. Zearalenone (479) is able to bind to these receptors and thus mimic the ability of 17 S-estradiol to stimulate transcriptional activity. Therefore, it... 

Shier WT, Shier AC, Xie W, Mirocha Cl (2001) Stracture-Activity Relationship for Human Estrogenic Activity in Zearalenone Mycotoxins. Toxicon 39 1435... 

Animals that consume moldy feeds excrete the estrogenic polyketide mycotoxins zearalenone (51) and zearalenol (52) in milk and milk products (Fig. 5,24). The same compound sometimes is found in beer. Zearalenol and zearalenone are synthesized by Fusarium species these compounds produce sterility and other reproductive problems in livestock (Beier and Nigg, 1992). 

The fermentation process can also decrease the amount of mycotoxins. Part of the toxins can be bound to yeast cells and thus removed from the wort. In addition, brewers yeast also has the ability to detoxify mycotoxins by bioconversion of mycotoxins to less toxic derivatives (Halady Shetty Jespersen, 2006 Inoue, Nagatomi, Uyama, Mochizuki, 2013). Mizutani, Nagatomi, and Mochizuki (2011) showed that the major part of ZEA (89.5%) was converted to 3-zearalenol, which has lower estrogenic activity than ZEA. 

Biomolecules labeled with (aUcyne)[Co2(CO)g] entities are among the most widely studied molecules in bioorganometallic chemistry, thanks to their ease of preparation and reasonable stabiUty [96], It is thus no surprise that the Uterature provides examples of peptides [97, 98], proteins [99], therapeutic drugs [100], abortifacient medications such as RU486, 35 [101], corticoids and androgens [102], methotrexate 37 [103], the mycotoxin zearalenone 36 [104, 105], estrogens [106-110] and pesticides [111] modified by this entity (Scheme 3.15). 

The presence of mycotoxins in food and feed may affect human and animal health on account of many different adverse health effects such as induction of cancer and mutagenicity, as well as estrogenic, gastrointestinal and kidney disorders. National and international organizations are constantly evaluating the risk that such mycotoxins pose to humans, resulting in statutory or guideline maximum permissible limits for the most widespread and toxic ones. ... 

Zearalenone (28), a naturally occurring mycotoxin and a secondary metabolite of Fusarium species, is notable because of its estrogenic and anabolic activity in animals (Pathre and Mirocha, 1976 Mirocha and Christensen, 1974). The structure of zearalenone indicates a biosynthetic pathway involving nine acetate units. 

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