Alternaria Toxins in Wheat during the 2004 to 2005 Argentinean Harvest

Abstract

The natural occurrence of Alternaria mycotoxins in Argentinean wheat from the zone 5 South during the 2004 to 2005 harvest was investigated in 64 wheat samples. All samples were highly contaminated with a wide range of fungal species. Alternaria was found as the main component of the mycota, with an infection percentage of 100%. Three mycotoxins produced by species of Alternaria were determined in wheat: alternariol, alternariol monomethyl ether, and tenuazonic acid. Alternariol was detected in 4 (6%) of 64 samples, with a range of 645 to 1,388 microg/kg (mean of 1,054 microg/kg); alternariol monomethyl ether, with a range of 566 to 7,451 microg/kg (mean of 2,118 microg/kg) in 15 (23%) of 64 samples; and tenuazonic acid in 12 (19%) of 64 samples, with a range of 1,001 to 8,814 microg/kg (mean, 2,313 microg/kg). Alternariol monomethyl ether was the predominant toxin, but tenuazonic acid was detected in higher concentrations. Alternariol was present in fewer samples and in lower levels than were the other toxins. Tenuazonic acid and alternariol monomethyl ether occurred together in four samples, while tenuazonic acid and alternariol co-occurred in one sample. This the first report of the natural occurrence of Alternaria mycotoxins in Argentinean wheat. Toxin levels were high, probably due to the heavy infection with Alternaria species found in the samples.

Content of the Alternaria mycotoxin tenuazonic acid in food commodities determined by a stable isotope dilution assay

“…An overview of the distribution of TA contamination in cereals is shown in Fig. 4, confirming the results of the above-mentioned study (Siegel et al 2009) that TA is widespread in cereals marketed in Germany, but with values about 500 times lower than reported in Argentina (Azcarate et al 2008) or China (Li and Yoshizawa 2000) and more similar to values found in Australian wheat (Webley et al 1997).…”

“…Based on the synthesis of [ 13 C 6 , 15 N]-TA, the SIDA allowed the determination of TA in tomato products with low limits of quantitation and high precision. Until now, TA had been predominantly determined in cereals (Webley et al 1997;Li and Yoshizawa 2000;Patriarca et al 2007;Azcarate et al 2008) and in tomatoes and their respective processing products (Scott and Kanhere 1980;Stack et al 1985;Mislivec et al 1987;Terminiello et al 2006;Da Motta and Soares 2001). It was the aim of this study to extend the SIDA developed for TA to other food commodities, especially to fruit juices and spices that had not been previously evaluated.…”

Precise determination of the Alternaria mycotoxins alternariol and alternariol monomethyl ether in cereal, fruit and vegetable products using stable isotope dilution assays

“…To the best of our knowledge, there are no reports on the content of AOH and AME in -not detectable, ∼ between LOD and LOQ Juice and wines AOH (μg/kg) AME (μg/kg) Red grape juice --Red wine "Vollreiflese" 4.9 0.3 White dessert wine, France --White wine "Spätlese" 1.2 -"Beerenauslese" wine 1 4.9 0.2 "Beerenauslese" wine 2 -0.2 "Trockenbeerenauslese" wine 2.1 0.1 -not detectable consumable cereal products up to now. However, both toxins were reported to occur in weathered wheat kernels in China (Li and Yoshizawa 2000) and in Argentinean wheat of the 2004/2005 harvest (Azcarate et al 2008) in high concentration, but with differing incidence of 91% (AOH) and 95% (AME) (Li and Yoshizawa 2000) compared with 6% (AOH) and 23% (AME) (Azcarate et al 2008). A similar study in Germany focusing on the 2000/2001 harvest of winter wheat found no relevant contamination with both toxins (Müller et al 2002).…”

Multi-microbial metabolites in fonio millet (acha) and sesame seeds in Plateau State, Nigeria

“…The concentrations in fonio (range = 14-1,049 lg/kg, median = 123 lg/kg) were much higher than those in sesame (range = 2-40 lg/kg, median = 11 lg/kg). TEN-AC has been reported to contaminate a wide range of food commodities including cereals [37][38][39]. Asam et al [39] detected up to 57 lg/kg TEN-AC in rye flour from Germany.…”