Distribution of deoxynivalenol, zearalenone, and their respective modified analogues in milling fractions of naturally contaminated wheat grains

Abstract

Mycotoxins are among the most abundant contaminants in food and feed worldwide. Therefore, in the EU maximum levels are established, e.g. for the frequently occurring Fusarium toxins deoxynivalenol (DON) and zearalenone (ZEA). Additional to DON and ZEA, modified mycotoxins are present in naturally contaminated grain products contributing significantly to the exposure of humans and animals with mycotoxins. Up to now data on the spatial distribution of many (masked) mycotoxins in the kernels of wheat are missing. The aim of the present study was to investigate the amounts of DON and ZEA as well as their most abundant derivatives DON-3-glucoside (DON-3G), 3- and 15-acetyl-DON, ZEA-14- and 16-glucoside and ZEA-14-sulphate (ZEA-14S) in mill fractions of naturally contaminated wheat batches using HPLC-MS/MS. The investigated distribution pattern in ten milling fractions is comparable among the three investigated different wheat batches. Interestingly, DON and DON-3G were found to be present to similar amounts in all fractions. In bran, the levels were only slightly higher than in the endosperm. By contrast, for ZEA and ZEA-14S a significantly higher amount of toxin is located in the fibre-rich fractions. The relative mass proportion of DON-3G comprises for only between 2.9 and 11.2% of the free DON, while the relative mass proportion of ZEA-14S is estimated to even exceed the amount of free ZEA in certain fractions. Acetylated DON derivatives and ZEA-glucosides were only detected in low amounts. The experimental results show that a significant reduction of the ZEA and ZEA-14S level in wheat flour is feasible by applying milling technology strategies. However, the almost evenly distribution of DON and DON-3G in all fractions does not allow for the technological removal of relevant toxin amounts. Furthermore, the relative share of masked forms was higher for ZEA derivatives than for the DON conjugates in the investigated wheat lots.

Impact of pre-harvest rainfall on the distribution of fusarium mycotoxins in wheat mill fractions

“…Fewer previous studies have investigated the effects of milling on distribution of ZON. Where studied, the distribution of ZON was less variable than DON and was consistently higher in the bran and offal fractions and lower in white flour fractions (Schwake-Anduschus, et al, 2015;TrigoStockli, Deyoe, Satumbaga, & Pedersen, 1996;Zheng, et al, 2014) and no significant seasonal differences in the distribution of ZON were observed (Edwards, et al, 2011).…”

“…Studies in several countries, using a range of varieties and different mills have identified that after milling there is a lower proportion of DON within the white flour fractions and higher proportion in the bran and offal fractions. The impact of dry milling of wheat on deoxynivalenol was reviewed by (Cheli, Pinotti, Rossi, & Dell'Orto, 2013) and (Kushiro, 2008) and subsequently reported in more recent publications (Brera, et al, 2013;Fernandes, Barros, Santo, & Camara, 2015;Savi, et al, 2016;Schwake-Anduschus, et al, 2015;Tibola, Fernandes, Guarienti, & Nicolau, 2015;Zhang & Wang, 2014;Zheng, et al, 2014). Typical concentrations in white flour are 50-80% of the cleaned grain DON concentration.…”

Risk assessment for mycotoxin contamination in fish feeds in Europe

“…Since mycotoxin contamination often concerns the outer layers of kernels, debranning can reduce DON contamination by 15 to 78% (Aureli and D'Egidio 2007;Rios et al 2009;Cheli et al 2010;Sovrani et al 2012). This leads to the conclusion that wheat bran is more contaminated with DON, ZEN and ENN B and B 1 than wheat flour (Vaclavikova et al 2013;Schwake-Anduschus et al 2015;Tibola et al 2015). Wheat bran was used at average levels of 6.8 ± 0.7% (mean ± SEM) in all 97 investigated fish feeds ( Fig.…”

Current methods for mycotoxins analysis and innovative strategies for their reduction in cereals: an overview

“…ZEN was found to be more concentrated in the fibre‐rich parts of grains. The efficiency of milling in reducing the contamination level is due to the removal of the fractions from further processing, which are more enriched with mycotoxins …”