TY - JOUR A1 - Siegel, David A1 - Andrae, K. A1 - Proske, Matthias A1 - Kochan, Cindy A1 - Koch, Matthias A1 - Weber, M. A1 - Nehls, Irene T1 - Dynamic covalent hydrazine chemistry as a selective extraction and cleanup technique for the quantification of the Fusarium mycotoxin zearalenone in edible oils N2 - A novel, cost-efficient method for the analytical extraction of the Fusarium mycotoxin zearalenone (ZON) from edible oils by dynamic covalent hydrazine chemistry (DCHC) was developed and validated for its application with high performance liquid chromatography-fluorescence detection (HPLC-FLD). ZON is extracted from the edible oil by hydrazone formation on a polymer resin functionalised with hydrazine groups and subsequently released by hydrolysis. Specifity and precision of this approach are superior to liquid partitioning or gel permeation chromatography (GPC). DCHC also extracts zearalanone (ZAN) but not α-/β-zearalenol or -zearalanol. The hydrodynamic properties of ZON, which were estimated using molecular simulation data, indicate that the compound is unaffected by nanofiltration through the resin pores and thus selectively extracted. The method's levels of detection and quantification are 10 and 30 µg/kg, using 0.2 g of sample. Linearity is given in the range of 10-20,000 µg/kg, the average recovery being 89%. Bias and relative standard deviations do not exceed 7%. In a sample survey of 44 commercial edible oils based on various agricultural commodities (maize, olives, nuts, seeds, etc.) ZON was detected in four maize oil samples, the average content in the positive samples being 99 µg/kg. The HPLC-FLD results were confirmed by HPLC-tandem mass spectrometry and compared to those obtained by a liquid partitioning based sample preparation procedure. KW - Zearalenone KW - Extraction KW - Edible oil KW - Maize KW - Dynamic covalent hydrazine chemistry KW - Hydrazone KW - SPE KW - Hydrodynamic radius KW - HPLC-FLD PY - 2010 U6 - https://doi.org/10.1016/j.chroma.2010.02.019 SN - 0021-9673 VL - 1217 IS - 15 SP - 2206 EP - 2215 PB - Elsevier CY - Amsterdam AN - OPUS4-21048 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, M.E.H. A1 - Steier, I. A1 - Köppen, Robert A1 - Proske, Matthias A1 - Korn, U. A1 - Koch, Matthias A1 - Siegel, David T1 - Cocultivation of phytopathogenic Fusarium and Alternaria strains affects fungal growth and mycotoxin production N2 - Aims: A laboratory study was conducted to evaluate the influence of cocultivation of toxigenic Fusarium (F.) and Alternaria (A.) fungi with respect to growth and mycotoxin production. Methods and Results: Fusarium culmorum Fc13, Fusarium graminearum Fg23 and two Alternaria tenuissima isolates (At18 and At220) were simultaneously or consecutively co-incubated on wheat kernels in an in vitro test system. Fungal biomass was quantified by determining ergosterol content. Three Fusarium toxins (DON, NIV and ZON) and three Alternaria toxins (AOH, AME and ALT) were analysed by a newly developed HPLC/MS/MS method. In simultaneous cocultures, the fungal biomass was enhanced up to 460% compared with individual cultures; Alternaria toxins were considerably depressed down to <5%. Combining At18 and At220 with Fg23 inhibited the toxin production of both fungal partners. In contrast, Fc13 increased its DON and ZON production in competitive interaction with both A. strains. Conclusions: The interfungal competitive effects aid the understanding of the processes of competition of both fungi in natural environments and the involvement of mycotoxins as antifungal factors. Significance and Impact of Study: Cocultivation significantly affects fungal growth and mycotoxin production of phytopathogenic Alternaria and Fusarium strains. The impact of mycotoxins on the interfungal competition is highlighted. KW - Alternaria KW - Cocultivation KW - Ergosterol KW - Fusarium KW - Interfungal competition KW - Multimycotoxin analysis PY - 2012 U6 - https://doi.org/10.1111/j.1365-2672.2012.05388.x SN - 1364-5072 VL - 113 IS - 4 SP - 874 EP - 887 PB - Wiley-Blackwell CY - Malden, Mass., USA AN - OPUS4-26932 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Siegel, David A1 - Feist, M. A1 - Proske, Matthias A1 - Koch, Matthias A1 - Nehls, Irene T1 - Degradation of the alternaria mycotoxins alternariol, alternariol monomethyl ether, and altenuene upon bread baking N2 - The stability of the Alternaria mycotoxins alternariol, alternariol monomethyl ether, and altenuene upon bread baking was investigated by model experiments using a spiked wholemeal wheat flour matrix. For alternariol and alternariol monomethyl ether, but not for altenuene, degradation products, formed through a sequence of hydrolysis and decarboxylation, could be identified in pilot studies. The simultaneous quantification of alternariol, alternariol monomethyl ether, altenuene, and the degradation products was achieved by a newly developed high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) multimethod. The obtained quantitative data indicate that the Alternaria mycotoxins are barely degraded during wet baking, while significant degradation occurs upon dry baking, with the stability decreasing in the order alternariol monomethyl ether > alternariol > altenuene. The novel degradation products could be detected after the wet baking of flour spiked with alternariol and in a sample survey of 24 commercial cereal based baking products. KW - Alternariol monomethyl ether KW - Alternariol KW - Altenuene KW - Degradation KW - Baking KW - Bread KW - HPLC-MS/MS PY - 2010 U6 - https://doi.org/10.1021/jf102156w SN - 0021-8561 SN - 1520-5118 VL - 58 IS - 17 SP - 9622 EP - 9630 PB - American Chemical Society CY - Columbus, Ohio AN - OPUS4-21909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -