TY - CONF A1 - Maul, Ronald A1 - Schwake-Anduschus, C. T1 - Minimisation of Fusarium Toxins Deoxynivalenol and Zearalenone after Harvest T2 - 4th MoniQA International Conference CY - Budapest, Hungary DA - 2013-02-26 PY - 2013 AN - OPUS4-27837 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Maskierte Mykotoxine - Relevanz in Lebens- und Futtermitteln T2 - BfR-Seminar CY - Berlin, Germany DA - 2013-06-05 PY - 2013 AN - OPUS4-28709 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Brodehl, Antje A1 - Koch, Matthias T1 - Mykotoxinkonjugate demaskieren N2 - Wenn in einem Lebensmittel keine Schimmelpilzgifte nachweisbar sind, muss das nicht bedeuten, dass keine enthalten sind. Prozesse der Lebensmittelverarbeitung, etwa das Mälzen in der Brauerei, führen dazu, dass Glucoside oder Sulfate der Toxine entstehen. Sie sind wenig charakterisiert und analytisch bisher kaum fassbar. KW - Mykotoxine KW - Lebensmittel KW - Referenzmaterial KW - ERM PY - 2013 DO - https://doi.org/10.1002/nadc.201390282 SN - 1439-9598 SN - 1521-3854 VL - 61 IS - 9 SP - 916 EP - 919 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-29614 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Development of an improved in vitro digestion model - influence on apparent zearalenone content in flour T2 - 34. Mycotoxin-Workshop CY - Braunschweig, Germany DA - 2012-05-14 PY - 2012 AN - OPUS4-26043 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Enhanced LC-MS/MS-Analysis of Cylindrospermopsin in Plant and Freshwater Matrices Using the Stable Isotope Dilution Assay T2 - 21st Meeting on Toxikologie CY - Paris, France DA - 2013-12-09 PY - 2013 AN - OPUS4-29746 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kittler, Katrin A1 - Schreiner, M. A1 - Krumbein, A. A1 - Manzei, S. A1 - Koch, Matthias A1 - Rohn, S. A1 - Maul, Ronald T1 - Uptake of the cyanobacterial toxin cylindrospermopsin in brassica vegetables N2 - Toxin-producing cyanobacterial species are increasingly being found in freshwater systems. However, literature on the impact of many cyanobacterial toxins on plants is scarce. Cylindrospermosin (CYN), a secondary metabolite of cyanobacteria such as Cylindrospermopsis and Aphanizomenon species, is a potent hepatotoxin and protein synthesis inhibitor. Worryingly, CYN is increasingly found in surface and drinking water worldwide causing human and animal intoxications. Further, exposure of crop plants to CYN by irrigation with contaminated water has already been shown. Therefore, in this study, horticulturally important and highly consumed Brassica species were investigated to determine the level of CYN in the leaves after exposure of the roots to the toxin. Treatment of Brassica oleracea var. sabellica, Brassica juncea, and Sinapis alba under varying experimental conditions showed significant CYN uptake, with CYN levels ranging from 10% to 21% in the leaves compared to the CYN concentration applied to the roots (18–35 µg/l). In seedlings, CYN concentrations of up to 49 µg/g fresh weight were observed. Thus, crop plants irrigated with CYN-containing water may represent a significant source of this toxin within the food chain. KW - Cylindrospermopsin KW - Plant systemic availability KW - Cyanobacterial toxin KW - Brassicaceae KW - Exposure source PY - 2012 DO - https://doi.org/10.1016/j.foodchem.2012.01.107 SN - 0308-8146 VL - 133 IS - 3 SP - 875 EP - 879 PB - Elsevier CY - Amsterdam [u.a.] ; Jena AN - OPUS4-25730 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Intense formation of "masked mycotoxins" during food processing T2 - 5th International Symposium on Recent Advances in Food Analysis (RAFA 2011) CY - Prague, Czech Republic DA - 2011-11-01 PY - 2011 AN - OPUS4-24527 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Warth, B. A1 - Schebb, N.H. A1 - Krska, R. A1 - Koch, Matthias A1 - Sulyok, M. T1 - In vitro glucuronidation kinetics of deoxynivalenol by human and animal microsomes and recombinant human UGT enzymes N2 - The mycotoxin deoxynivalenol (DON), formed by Fusarium species, is one of the most abundant mycotoxins contaminating food and feed worldwide. Upon ingestion, the majority of the toxin is excreted by humans and animal species as glucuronide conjugate. First in vitro data indicated that DON phase II metabolism is strongly species dependent. However, kinetic data on the in vitro metabolism as well as investigations on the specific enzymes responsible for DON glucuronidation in human are lacking. In the present study, the DON metabolism was investigated using human microsomal fractions and uridine-diphosphoglucuronyltransferases (UGTs) as well as liver microsomes from five animal species. Only two of the twelve tested human recombinant UGTs led to the formation of DON glucuronides with a different regiospecificity. UGT2B4 predominantly catalyzed the formation of DON-15-O-glucuronide (DON-15GlcA), while for UGT2B7 the DON-3-O-glucuronide (DON-3GlcA) metabolite prevailed. For human UGTs, liver, and intestinal microsomes, the glucuronidation activities were low. The estimated apparent intrinsic clearance (Clapp,int) for all human UGT as well as tissue homogenates was <1 mL/min mg protein. For the animal liver microsomes, moderate Clapp,int between 1.5 and 10 mL/min mg protein were calculated for carp, trout, and porcine liver. An elevated glucuronidation activity was detected for rat and bovine liver microsomes leading to Clapp,int between 20 and 80 mL/min mg protein. The obtained in vitro data points out that none of the animal models is suitable for estimating the human DON metabolism with respect to the metabolite pattern and formation rate. KW - Deoxynivalenol KW - Glucuronidation KW - Uridine-diphosphoglucuronyltransferases (UGT) KW - Human recombinant UGT KW - Trichothecene KW - Phase II metabolism PY - 2015 DO - https://doi.org/10.1007/s00204-014-1286-7 SN - 0340-5761 SN - 1432-0738 VL - 89 IS - 6 SP - 949 EP - 960 PB - Springer CY - Berlin ; Heidelberg [u.a.] AN - OPUS4-33204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Drzymala, Sarah A1 - Herrmann, Antje A1 - Maul, Ronald A1 - Pfeifer, Dietmar A1 - Garbe, L.-A. A1 - Koch, Matthias T1 - In vitro phase I metabolism of cis-zearalenone N2 - The present study investigates the in vitro phase I metabolism of cis-zearalenone (cis-ZEN) in rat liver microsomes and human liver microsomes. cis-ZEN is an often ignored isomer of the trans-configured Fusarium mycotoxin zearalenone (trans-ZEN). Upon the influence of (UV-) light, trans-ZEN isomerizes to cis-ZEN. Therefore, cis-ZEN is also present in food and feed. The aim of our study was to evaluate the in vitro phase I metabolism of cis-ZEN in comparison to that of trans-ZEN. As a result, an extensive metabolization of cis-ZEN is observed for rat and human liver microsomes as analyzed by HPLC-MS/MS and high-resolution MS. Kinetic investigations based on the substrate depletion approach showed no significant difference in rate constants and half-lives for cis- and trans-ZEN in rat microsomes. In contrast, cis-ZEN was depleted about 1.4-fold faster than trans-ZEN in human microsomes. The metabolite pattern of cis-ZEN revealed a total of 10 phase I metabolites. Its reduction products, α- and β-cis-zearalenol (α- and β-cis-ZEL), were found as metabolites in both species, with α-cis-ZEL being a major metabolite in rat liver microsomes. Both compounds were identified by co-chromatography with synthesized authentic standards. A further major metabolite in rat microsomes was monohydroxylated cis-ZEN. In human microsomes, monohydroxylated cis-ZEN is the single dominant peak of the metabolite profile. Our study discloses three metabolic pathways for cis-ZEN: reduction of the keto-group, monohydroxylation, and a combination of both. Because these routes have been reported for trans-ZEN, we conclude that the phase I metabolism of cis-ZEN is essentially similar to that of its trans isomer. As trans-ZEN is prone to metabolic activation, leading to the formation of more estrogenic metabolites, the novel metabolites of cis-ZEN reported in this study, in particular α-cis-ZEL, might also show higher estrogenicity. KW - Cis-ZEN KW - Phase I metabolism KW - LC-MS/MS KW - HRMS KW - Depletion kinetics PY - 2014 DO - https://doi.org/10.1021/tx500312g SN - 0893-228X SN - 1520-5010 VL - 27 IS - 11 SP - 1972 EP - 1978 PB - Soc. CY - Washington, DC, USA AN - OPUS4-32071 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - "Maskierte Schimmelpilzgifte" - Relevanz für Bäcker, Brauer und Analytiker T2 - Institutskolloquium des Zentralen Instituts des Sanitätsdienstes der Bundeswehr Kiel CY - Kiel, Germany DA - 2013-04-18 PY - 2013 AN - OPUS4-28781 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schloß, Svenja A1 - Wedell, Ines A1 - Koch, Matthias A1 - Rohn, S. A1 - Maul, Ronald T1 - Biosynthesis and characterization of 15N6-labeled phomopsin A, a lupin associated mycotoxin produced by Diaporthe toxica N2 - The hepatotoxin phomopsin A (PHO-A), a secondary metabolite mainly produced by the fungus Diaporthe toxica, occurs predominantly on sweet lupins. Along with the growing interest in sweet lupins for food and feed commodities, concerns have been raised about fungal infestations, and consequently, about the determination of PHO-A. High performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) represents the most suitable analytical technique for sensitive and selective detection of mycotoxins including PHO-A. However, isotopic labeled substances are needed as internal standards for a reliable and convenient quantification. As no isotope standard for PHO-A is currently available, a biosynthesis of fully 15N6-labeled PHO-A was established by cultivation of D. toxica on defined media containing Na15NO3 and 15N-labeled yeast extract as the only nitrogen sources. The identity of 15N6-PHO-A was confirmed by high resolution mass spectrometry. The new 15N6-labeled standard will facilitate the method development for PHO-A including a more accurate quantification by LC-MS/MS. KW - Phomopsin A KW - Lupins KW - Diaporthe toxica KW - Stable isotope dilution assay KW - Isotopic labeled internal standard KW - Biosynthesis PY - 2015 DO - https://doi.org/10.1016/j.foodchem.2014.12.056 SN - 0308-8146 VL - 177 SP - 61 EP - 65 PB - Elsevier CY - Amsterdam [u.a.] ; Jena AN - OPUS4-32464 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwake-Anduschus, C. A1 - Proske, Matthias A1 - Sciurba, E. A1 - Muenzing, K. A1 - Koch, Matthias A1 - Maul, Ronald T1 - Distribution of deoxynivalenol, zearalenone, and their respective modified analogues in milling fractions of naturally contaminated wheat grains N2 - Mycotoxins are among the most abundant contaminants in food and feed worldwide. Therefore, in the EU maximum levels are established, e.g. for the frequently occurring Fusarium toxins deoxynivalenol (DON) and zearalenone (ZEA). Additional to DON and ZEA, modified mycotoxins are present in naturally contaminated grain products contributing significantly to the exposure of humans and animals with mycotoxins. Up to now data on the spatial distribution of many (masked) mycotoxins in the kernels of wheat are missing. The aim of the present study was to investigate the amounts of DON and ZEA as well as their most abundant derivatives DON-3-glucoside (DON-3G), 3- and 15-acetyl-DON, ZEA-14- and 16-glucoside and ZEA-14-sulphate (ZEA-14S) in mill fractions of naturally contaminated wheat batches using HPLC-MS/MS. The investigated distribution pattern in ten milling fractions is comparable among the three investigated different wheat batches. Interestingly, DON and DON-3G were found to be present to similar amounts in all fractions. In bran, the levels were only slightly higher than in the endosperm. By contrast, for ZEA and ZEA-14S a significantly higher amount of toxin is located in the fibre-rich fractions. The relative mass proportion of DON-3G comprises for only between 2.9 and 11.2% of the free DON, while the relative mass proportion of ZEA-14S is estimated to even exceed the amount of free ZEA in certain fractions. Acetylated DON derivatives and ZEA-glucosides were only detected in low amounts. The experimental results show that a significant reduction of the ZEA and ZEA-14S level in wheat flour is feasible by applying milling technology strategies. However, the almost evenly distribution of DON and DON-3G in all fractions does not allow for the technological removal of relevant toxin amounts. Furthermore, the relative share of masked forms was higher for ZEA derivatives than for the DON conjugates in the investigated wheat lots. KW - Mass spectrometry KW - Fusarium mycotoxins KW - Masked mycotoxin KW - Flour extraction KW - Bran PY - 2015 DO - https://doi.org/10.3920/WMJ2014.1818 SN - 1875-0710 SN - 1875-0796 VL - 8 IS - 4 SP - 433 EP - 443 PB - Wageningen Academic Publishers CY - Wageningen AN - OPUS4-33833 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Evaluierung der Biotransformation von Substanzen in verschiedenen Umweltkompartimenten T2 - Forum Junger Umweltwissenschaftlern 2013 CY - Blomberg (North Rhine-Westphalia), Germany DA - 2013-05-27 PY - 2013 AN - OPUS4-28708 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Pielhau, Ramona A1 - Koch, Matthias T1 - Evaluation of an extraction method and spin column cleanup procedure for Fusarium mycotoxins and their masked derivatives from grain matrix N2 - Fusarium mycotoxins in foodstuffs at levels in violation of allowed legal limits belong to the most frequently occurring type of food contamination. Out of the large variety of known mycotoxins, deoxynivalenol (DON), zearalenone (ZEN), and the T-toxins are the most prevalent and are responsible for extensive and recurring economic damage. For ensuring consumer safety, it is required to continually identify faster, simpler and more reliable analytical methodologies. In the present work, miniaturized centrifugation (spin) columns for the extraction of mycotoxins from grain samples were investigated, with a focus on matrix removal, applicability of different extraction solvents, and recovery of mycotoxin. The method was further extended to the extraction of naturally occurring DON and ZEN conjugates (masked mycotoxins). The spin column method was observed to routinely provide a total matrix reduction of >90% from typical wheat samples in a single centrifugation step. The use of H2O/ACN (20/80; v/v) as an extraction solvent provided non-masked DON, ZEN and T-toxin recoveries of greater than 80%. For the masked DON and ZEN conjugates (DON-3-glucoside and ZEN-14-sulfate), recoveries were lower. Overall, the evaluated miniaturized spin column procedure enabled rapid loss-free extraction of unconjugated mycotoxins from conventional grain matrix and a significantly reduced matrix load in the extracts. KW - Fusarium mycotoxins KW - Spin-columns KW - Cleanup effectiveness KW - Masked mycotoxins KW - Recovery rate PY - 2014 DO - https://doi.org/10.1016/j.foodcont.2013.12.003 SN - 0956-7135 VL - 40 SP - 151 EP - 156 PB - Elsevier CY - Amsterdam AN - OPUS4-31609 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Kittler, Katrin A1 - Koch, Matthias A1 - Nehls, Irene T1 - Bakterielle Migranten - Algentoxine als neue Herausforderung in der Umweltanalytik N2 - Bioaktive Sekundärstoffe aus Cyanobakterien stellen eine Quelle für pharmazeutisch interessante Wirkstoffkandidaten wie auch eine Herausforderung für die Umwelt- und Lebensmittelanalytik dar. Die Identifizierung ist allerdings nicht trivial. KW - Cyanotoxine KW - Analytik PY - 2011 SN - 0344-1733 SN - 1610-8256 IS - August SP - 56 EP - 58 PB - Vogel CY - Würzburg AN - OPUS4-25733 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Fusarium Mycotoxins in Naturally Contaminated Wheat Mill Fractions T2 - World Mycotoxin Forum CY - Vienna (Austria) DA - 2014-11-10 PY - 2014 AN - OPUS4-31851 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brodehl, Antje A1 - Möller, Anne A1 - Kunte, Hans-Jörg A1 - Koch, Matthias A1 - Maul, Ronald T1 - Biotransformation of the mycotoxin zearalenone by fungi of the genera Rhizopus and Aspergillus N2 - Zearalenone (ZEN) is a nonsteroidal estrogenic mycotoxin biosynthesized by various Fusarium fungi. These fungal species frequently infest grains; therefore, ZEN represents a common contaminant in cereal products. The biotransformation of ZEN differs significantly from species to species, and several metabolites are known to be formed by animals, plants, and microorganisms. The aim of the present study was to investigate the microbial conversion of ZEN by species of the genera Rhizopus and Aspergillus representing relevant fungi for food processing (e.g. fermentation). To monitor the ZEN metabolism, ZEN was added to liquid cultures of the different fungal species. After a period of 3 days, the media were analyzed by HPLC-MS/MS for metabolite formation. Two Aspergillus oryzae strains and all seven Rhizopus species were able to convert ZEN into various metabolites, including ZEN-14-sulfate as well as ZEN-O-14- and ZEN-O-16-glucoside. Microbial transformation of ZEN into the significantly more estrogenic α-zearalenol (α-ZEL) was also observed. Additionally, a novel fungal metabolite, α-ZEL-sulfate, was detected. Semi-quantification of the main metabolites indicates that more than 50% of initial ZEN may be modified. The results show that fungal strains have the potential to convert ZEN into various metabolites leading to a masking of the toxin, for example in fermented food. KW - Microbial conversion KW - Metabolites KW - Fermentation KW - Alpha-zearalenol KW - Conjugation KW - Mycotoxin biotransformation KW - Zearalenone-sulfate PY - 2014 DO - https://doi.org/10.1111/1574-6968.12586 SN - 0378-1097 SN - 1574-6968 VL - 359 IS - 1 SP - 124 EP - 130 PB - Wiley-Blackwell CY - Malden, Mass., USA AN - OPUS4-31636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Vergleich von in-vitro-Metabolismusmodellen mit in vivo-Daten am Beispiel der Rotkleeisoflavone T2 - 39. Deutscher Lebensmittelchemikertag CY - Stuttgart, Germany DA - 2010-09-20 PY - 2010 AN - OPUS4-22323 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Der Keimprozess von Getreide als Auslöser für die Maskierung des Mykotoxins Deoxynivalenol im Lebensmittel T2 - 40. Deutscher Lebensmittelchemikertag 2011 CY - Halle (Saale), Germany DA - 2011-09-12 PY - 2011 AN - OPUS4-24234 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Biosynthesis of zearalenone conjugates by fungi N2 - Zearalenone (ZEN) and its sulfate and glucoside conjugates have been detected in (a broad variety of) food and feed commodities1. Both conjugated derivatives are formed as part of fungal or plant secondary metabolism and thus, belong to the group of modified mycotoxins2. After consumption of contaminated foodstuff, the conjugates can be hydrolyzed by human intestinal microbiota leading to liberation of ZEN that implies an underestimation of the true ZEN exposure. In order to include ZEN conjugates in routine analysis, as well as for toxicological investigation reliable standards are needed. The objective of the present study was to develop a simple and economic method for biosynthesis of ZEN conjugates. Preceding experiments on the biotransformation of ZEN by Rhizopus and Aspergillus species showed a mixed metabolite formation3. Therefore, these known ZEN conjugating fungal strains were screened for their potential to selectively synthesize the ZEN derivatives ZEN-14-sulfate (Z14S), ZEN-14-glucoside (Z14G) and ZEN-16-glucoside (Z16G). The screening was conducted by adding ZEN to liquid fungal cultures. Cultivation conditions and ZEN incubation time were varied. All media samples were analyzed for metabolite formation by HPLC-MS/MS. Z14S was exclusively formed by A. oryzae. Under optimized conditions a specific biosynthesis of Z14G by R. oryzae and Z16G by R. oligosporus was achieved. After liquid-liquid-extraction and preparative chromatographic cleanup 1H-NMR purities of ≥ 73% for Z14S, ≥ 82% for Z14G and ≥ 50% for Z16G were obtained. In addition, a consecutive biosynthesis was developed by first using Fusarium graminearum for ZEN biosynthesis on rice based liquid medium. After inactivation of Fusarium the subsequent conjugation reaction was conducted utilizing Aspergillus and Rhizopus species under the various optimized conditions. In this study an easy and cost-efficient biosynthesis for Z14S, Z14G and Z16G was developed. The developed biosynthesis could be also used for other metabolites like ZEL conjugates. Our results of the in vitro screening indicate also the formation of a ZEL-glucoside and α ZEL-sulfate as major metabolites by R. oryzae. In sum, under optimized cultivation conditions fungi can be easily utilized for a targeted and stereospecific synthesis of ZEN conjugates. T2 - 10th World Mycotoxin Forum Conference CY - Amsterdam, The Netherlands DA - 12.03.2018 KW - Mycotoxins KW - Food safety KW - Analytical standards PY - 2018 AN - OPUS4-44547 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -