TY - JOUR A1 - Merkel, Stefan A1 - Köppen, Robert A1 - Koch, Matthias A1 - Emmerling, Franziska A1 - Nehls, Irene T1 - Ergotaminine N2 - The title compound {systematic name: (6aR,9S)-N-[(2R,5S,10aS,10bS)-5-benzyl-10b-hydroxy-2-methyl-3,6-dioxooctahydro-8H-oxazolo[3,2-a]pyrrolo[2,1-c]pyrazin-2-yl]-7-methyl-4,6,6a,7,8,9-hexahydroindolo[4,3-fg]quinoline-9-carboxamide}, C33H35N5O5, was formed by an epimerization reaction of ergotamine. The non-aromatic ring (ring C of the ergoline skeleton) directly fused to the aromatic rings is nearly planar [maximum deviation = 0.317 (4) Å] and shows an envelope conformation, whereas ring D, involved in an intramolecular N–H···N hydrogen bond exhibits a slightly distorted chair conformation. The structure displays chains running approximately parallel to the diagonal of bc plane that are formed through N–H···O hydrogen bonds. PY - 2012 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-254528 DO - https://doi.org/10.1107/S1600536812003674 SN - 1600-5368 VL - 68 IS - 3 SP - o610-o611, sup1-sup11 PB - Munksgaard CY - Copenhagen AN - OPUS4-25452 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Merkel, Stefan A1 - Dib, Baha A1 - Maul, Ronald A1 - Köppen, Robert A1 - Koch, Matthias A1 - Nehls, Irene T1 - Degradation and epimerization of ergot alkaloids after baking and in vitro digestion N2 - The degradation and epimerization of ergot alkaloids (EAs) in rye flour were investigated after baking cookies and subsequently subjecting them to an in vitro digestion model. Different steps of digestion were analyzed using salivary, gastric, and duodenal juices. The degradation and bidirectional conversion of the toxicologically relevant (R)-epimers and the biologically inactive (S)-epimers for seven pairs of EAs were determined by a HPLC method coupled with fluorescence detection. Baking cookies resulted in degradation of EAs (2–30 %) and a shift in the epimeric ratio toward the (S)-epimer for all EAs. The applied digestion model led to a selective toxification of ergotamine and ergosine, two ergotamine-type EAs. The initial percentage of the toxic (R)-epimer in relation to the total toxin content was considerably increased after digestion of cookies. Ergotamine and ergosine increased from 32 to 51 % and 35 to 55 %, respectively. In contrast, EAs of the ergotoxine type (ergocornine, α- and β-ergocryptine, and ergocristine) showed an epimeric shift toward their biologically inactive (S)-epimers. Further experiments indicated that the selective epimerization of ergotamine EAs occurs in the duodenal juice only. These results demonstrate that toxification of EAs in the intestinal tract should be taken into consideration. KW - HPLC-FLD KW - Claviceps purpurea KW - Rye KW - Ergotoxine KW - Ergotamine KW - Deoxynivalenol KW - Nivalenol KW - Zearalenone KW - Food KW - ERM KW - Quality assurance PY - 2012 DO - https://doi.org/10.1007/s00216-012-6386-8 SN - 1618-2642 SN - 1618-2650 VL - 404 IS - 8 SP - 2489 EP - 2497 PB - Springer CY - Berlin AN - OPUS4-27119 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Merkel, Stefan A1 - Köppen, Robert A1 - Koch, Matthias A1 - Emmerling, Franziska A1 - Nehls, Irene T1 - Lysergol monohydrate N2 - In the title compound [systematic name: (7-methyl-4,6,6a,7,8,9-hexahydroindolo[4,3,2-fg]quinoline-9-yl)methanol monohydrate], C16H18N2O·H2O, the non-aromatic ring (ring C of the ergoline skeleton) directly fused to the aromatic rings is nearly planar, with a maximum deviation of 0.659 (3) Å, and shows an envelope conformation. In the crystal, hydrogen bonds between the lysergol and water molecules contribute to the formation of layers parallel to (10-2). PY - 2012 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-254015 DO - https://doi.org/10.1107/S1600536812002632 SN - 1600-5368 VL - 68 IS - 2 SP - o523, sup1 EP - sup8 PB - Munksgaard CY - Copenhagen AN - OPUS4-25401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - 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 -