T-2 and HT-2 toxins in oat flakes: development of a certified reference material.

Trichothecene mycotoxins, with T-2 and HT-2 toxins being the main representatives of the type A subgroup, are naturally and worldwide occurring contaminants frequently found in grain-based food and feed. Due to the high consumption of these products and the potential health risk associated herewith, concerns about the safety and quality of food and feed have increased over the last decades at both governmental and consumer levels. Since it is not possible to avoid their occurrence, tremendous efforts have been performed to identify and monitor mycotoxins in food and feed to make their consumption safe.

Novel solid-phase extraction for epimer-specific quantitation of ergot alkaloids in rye flour and wheat germ oil.

Ergot alkaloids and their epimer-specific determination have gained increasing importance for food safety. A solid-phase extraction and cleanup method based on sodium-neutralized strong cation exchange (Na(+)-SCX) was developed to quantitate 12 priority ergot alkaloids in rye flour and wheat germ oil by HPLC fluorescence analysis. Sample preparation is achieved by omitting acidic and alkaline conditions enabling minimized epimerization, which is necessary to determine ergot alkaloids according to their natural distribution in foods.

Development and certification of a reference material for Fusarium mycotoxins in wheat flour.

Deoxynivalenol (DON), nivalenol (NIV) and zearalenone (ZEN) are toxic secondary metabolites produced by several species of Fusarium fungi. These mycotoxins are often found together in a large variety of cereal-based foods, which are regulated by maximum content levels of DON and ZEN. To date, suitable certified reference materials (CRM) intended for quality control purposes are lacking for these Fusarium mycotoxins.

Photochemical trans-/cis-isomerization and quantitation of zearalenone in edible oils.

The emphasis of the present work was to investigate the photochemical conversion of trans- to cis-zearalenone in edible oils under real-life conditions. For quantitation purposes a cis-zearalenone standard was synthesized and characterized for its identity and purity (≥95%) by (1)H NMR, X-ray crystallography, HPLC fluorescence and mass spectrometric detection. In a sample survey of 12 edible oils (9 corn oils, 3 hempseed oils) from local supermarkets all corn oils contained trans-zearalenone (median 194 μg/kg), but no cis-zearalenone was detected.

Determination of the Alternaria mycotoxin tenuazonic acid in cereals by high-performance liquid chromatography-electrospray ionization ion-trap multistage mass spectrometry after derivatization with 2,4-dinitrophenylhydrazine.

Tenuazonic acid (TA) is a major Alternaria mycotoxin. In the present work a novel approach for the detection of TA in cereals by liquid chromatography-ion-trap multistage mass spectrometry after derivatization with 2,4-dinitrophenylhydrazine is described. The product of the derivatization reaction and its major MS(2) fragments were characterised by Fourier transform-ion cyclotron resonance tandem mass spectrometry.

Distribution of trichothecenes, zearalenone, and ergosterol in a fractionated wheat harvest lot.

To investigate possible co-occurrences of type B trichothecenes and zearalenone within a Fusarium culmorum-infected wheat harvest lot, kernels were fractionated into six groups by visual criteria. The Fusarium-damaged kernels were subdivided into white, shrunken, and red kernel groups, and the remaining kernels were sorted into healthy, black spotted, and nonspecific groups. The distribution patterns of nivalenol, deoxynivalenol, zearalenone, and ergosterol were determined for possible correlations.