Mycotoxins from Alternaria

Alternaria toxins are mycotoxins produced by Alternaria species. These fungi cause serious diseases in many crops such as cereals, oil seeds, and fruits. More than 70 Alternaria toxins have been reported and only some of them have been physicochemically characterized. Among the most common in food commodities, alternariol (AOH), alternariol methyl ether (AME), altenuene (ALT), and tenuazonic acid were mainly studied. Available in vitro data indicate that AOH, AME, and ALT are hydroxylated, mostly to catechol metabolites, and form glucuronide and sulfate conjugates. AOH and AME are genotoxic in bacteria and mammalian cells in vitro. Although there are no in vivo genotoxicity or carcinogenicity data available for Alternaria toxins, some indications of precancerous changes have been reported in esophageal mucosa of mice. In this review, the state of the art about the toxic effects of the major Alternaria toxins will be reported, and new data about their stability under in vitro human simulated gastrointestinal conditions will be described.