TY - JOUR A1 - Merkel, Stefan A1 - Köppen, Robert A1 - Koch, Matthias A1 - Emmerling, Franziska A1 - Nehls, Irene T1 - Lumi-ergometrine - structural identification and occurrence in sclerotia N2 - The fungus Claviceps purpurea grows on grasses and cereal grains and produces six predominant ergot alkaloids. These toxic substances undergo different Transformation reactions during storage and cereal processing. One of these reactions is the addition of water to a double bond in the ergoline skeleton. Since light is required for this process, the substances formed were named lumi-ergot alkaloids. From these, a new asymmetric carbon and consequently two epimers with different polarities are formed. For investigations of lumi-ergot alkaloids, ergometrine was used exemplarily as it represents one of the six ergot Alkaloids predominantly formed by Claviceps purpurea. The main reaction product, the less polar compound of the two lumiergometrine epimers, was separated by HPLC and unambiguously identified as 10-(S)-lumi-ergometrine using X-ray structural analysis. A HPLC-MS/MS method was developed for the detection of this substance in sclerotia extracts. Using this method, the existence of both epimeric forms of lumiergometrinecould be proved in the sclerotia. This is the first time that the existence of a lumi-transformation product of ergot alkaloids was proved in naturally grown samples. KW - Lumi-ergot alkaloids KW - Sclerotia KW - Claviceps purpurea KW - HPLC-MS/MS PY - 2012 DO - https://doi.org/10.1007/s12550-011-0116-5 SN - 0178-7888 VL - 28 IS - 1 SP - 59 EP - 66 PB - Springer CY - Berlin; Heidelberg AN - OPUS4-25442 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Müller, C. A1 - Rieß, Stephanie A1 - Koch, Matthias A1 - Methner, F.-J. A1 - Nehls, Irene T1 - Germination induces the glucosylation of the Fusarium mycotoxin deoxynivalenol in various grains N2 - In food, the mycotoxin deoxynivalenol (DON) often occurs in conjunction with its 3-β-D-glucopyranoside (D3G). The transformation of DON to D3G through glucosylation is catalysed by plant enzymes, however, the exact circumstances are not well understood. In order to investigate the role of enzymatic glucosylation in germinating grains, DON treated kernels were steeped and germinated under laboratory conditions. Furthermore, the effect of malting on the DON content of the contaminated barley was investigated. In all cases, DON and its derivatives were quantified by HPLC-MS/MS before, during and after the experiments. Amongst the six tested cereals; wheat, rye, barley, spelt, and millet transformed DON to D3G during germination whilst the oats were inactive. For wheat, barley, and spelt the initial DON content was reduced by 50%, with the loss being almost entirely accounted for by D3G formation. As D3G might be cleaved during digestion, the elevated D3G concentration may obscure the toxicologically relevant DON content in processed food and beer. The germination process has a major influence on the 'masking' of DON, leading to high quantities of D3G that may be missed in common mycotoxin analyses. KW - Mycotoxins KW - Masked mycotoxins KW - Deoxynivalenol (DON) KW - DON-3-glucoside KW - Acetyl-DON KW - Germination KW - Malting PY - 2012 DO - https://doi.org/10.1016/j.foodchem.2011.08.077 SN - 0308-8146 VL - 131 IS - 1 SP - 274 EP - 279 PB - Elsevier CY - Amsterdam [u.a.] ; Jena AN - OPUS4-25732 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -