Masked mycotoxins: A review

Abstract

The aim of this review is to give a comprehensive overview of the current knowledge on plant metabolites of mycotoxins, also called masked mycotoxins. Mycotoxins are secondary fungal metabolites, toxic to human and animals. Toxigenic fungi often grow on edible plants, thus contaminating food and feed. Plants, as living organisms, can alter the chemical structure of mycotoxins as part of their defence against xenobiotics. The extractable conjugated or non-extractable bound mycotoxins formed remain present in the plant tissue but are currently neither routinely screened for in food nor regulated by legislation, thus they may be considered masked. Fusarium mycotoxins (deoxynivalenol, zearalenone, fumonisins, nivalenol, fusarenon-X, T-2 toxin, HT-2 toxin, fusaric acid) are prone to metabolisation or binding by plants, but transformation of other mycotoxins by plants (ochratoxin A, patulin, destruxins) has also been described. Toxicological data are scarce, but several studies highlight the potential threat to consumer safety from these substances. In particular, the possible hydrolysis of masked mycotoxins back to their toxic parents during mammalian digestion raises concerns. Dedicated chapters of this article address plant metabolism as well as the occurrence of masked mycotoxins in food, analytical aspects for their determination, toxicology and their impact on stakeholders.

Survey of mycotoxins in Southern Brazilian wheat and evaluation of immunoassay methods

“…The antibodies designed for DON may also cross-react against DON-3β-glucoside (DON-3G) and monoacetylated derivatives (3-ADON) (Tangni et al, 2010). The presence of acetylated DON derivatives (15-ADON and 3-ADON) has been generally reported together with DON, especially in cereals, although at relatively lower level than DON levels (Berthiller et al, 2013).…”

“…Commercial kits based on enzyme-linked immunosorbent assays (ELISAs) are widely used for screening commodities and foods, given their low cost and easy operation (Lattanzio et al, 2009). Although, these assays allow high throughput, disadvantages related to antibody cross-reactivity can lead to overestimation of the targeted mycotoxin compared to a reference (chromatographic) method (Berthiller et al, 2013;Liu et al 2012). The main objective of this study was to quantify and assess the spatial variability of DON, ZEA and OTA in commercial grain harvested in southern Brazil, in the 2015 season, using UHPLC-MS/MS.…”

Comparative studies about fungal colonization and deoxynivalenol translocation in barley plants inoculated at the base with Fusarium graminearum, Fusarium culmorum and Fusarium pseudograminearum

“…Therefore DON interferes with the protein synthesis mechanism of the plant, blocking its defense mechanisms, thus facilitating the advancement of the fungus from the base of the culm to the head. DON, being water-soluble, is transported remotely through the transpiration flux in xylem vessels, accumulating also in elevated quantities at the head level (Berthiller et al 2013). The systemic translocation of DON from the stem base to the head was also reported in soft wheat by Covarelli et al (2012) and Winter et al (2013).…”

The Occurrence of Mycotoxins in Beers from Retail Shops

“…is the most well known and so far most studied conjugate of trichothecenes (Velíšek et al, 2009;Berthiller et al, 2007). Currently it remains unclear whether D3G as a detoxifi cation plant product exhibits acute toxicity or whether it can cleave back to DON in the body (Berthiller et al, 2007;Berthiller et al, 2013).…”