Survey of deoxynivalenol and deoxynivalenol-3-glucoside in cereal-based products by liquid chromatography electrospray ionization tandem mass spectrometry

It is well known that cereal crops exposed to deoxynivalenol (DON) infection are capable of detoxifying this mycotoxin through the plant metabolism. In this context, one major pathway is the conjugation of DON to a glucose moiety giving rise to 3-β-D-glucopyranosyl-4-deoxynivalenol (D3G). Though no longer toxic for plants, this metabolite may potentially be hydrolysed in the digestive tract of humans and animals, releasing thus the toxic precursor (DON). The co-occurrence of DON and D3G in cereal-based products has already been reported but data about their absolute and relative concentrations are still insufficient. In order to contribute to a better understanding of the significance of D3G, the quantitative determination of DON and D3G has been carried out in 22 cereal samples and 4 malt-based products collected from 9 countries by liquid chromatography-tandem mass spectrometry (LCMS/ MS). DON was detected in all cereal samples (min: 3 µg/kg; max: 2,864 µg/kg; median: 176 µg/kg) but only in 1 malt-based product (16 µg/kg) whereas D3G was detected in 21 cereal samples (min: <1 µg/kg; max: 367 µg/kg; median: 19 µg/kg) and only in 1 malt-based product (6 µg/kg). The proportion of D3G in relation to DON concentration was within a 6-29% range with an average value at 12±7% in the tested samples.