Alternaria toxins in wheat during the 2004 to 2005 Argentinean harvest

AZCARATE, P.; PATRIARCA, A.; TERMINIELLO, L.; FERNÁNDEZ PINTO, V.

JOURNAL OF FOOD PROTECTION

International Association for Food Protection

Lugar: Iowa, USA; Año: 2008 vol. 71 p. 1262 - 1265

0362-028X

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 ìg/kg (mean of 1,054 ìg/kg); alternariol monomethyl ether, with a range of 566 to 7,451 ìg/kg (mean of 2,118 ìg/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 ìg/kg (mean, 2,313 ìg/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.