Masked mycotoxins and mycotoxin derivatives in food: The hidden menace

Abstract

Conjugated or masked mycotoxins first came to attention in the mid-1980s, mainly from clinical observations on animals affected by mycotoxicoses fed with apparently low-level mycotoxin-contaminated feed. The unexpected toxicity was attributed to the presence of conjugated forms of mycotoxins, possibly generated by the plant metabolism, which were undetected by the analytical methods commonly used for unmodified mycotoxins. These derivatives could be hydrolysed to the precursor toxins in the digestive tracts of animals, or could exert toxic effects comparable to those imputable to free mycotoxins. It soon became evident that mycotoxins can be structurally modified not only by interactions with plants, but also by food processing technologies, and also that the derivatives formed in the latter case may preserve the original toxicity of their precursors. The occurrence of masked mycotoxins formed by plant metabolism or mycotoxin derivatives due to food processing will be reported in this chapter, whereas data on derivatives formed by animal metabolism will not be included, since they have been extensively reported in the literature (Galtier 1998). Indeed, although metabolic plant-derived transformations and process-induced modifications of mycotoxins have been studied for many years, they are surprisingly scarcely mentioned in the literature, at least not for all important mycotoxins. In this chapter, the term masked mycotoxins will be specifically intended for mycotoxins conjugated to other molecules (i.e. proteins, carbohydrates, etc.) and which can be released after ingestion. © 2010 Springer-Verlag Berlin Heidelberg.