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 - TY - CONF A1 - Maul, Ronald T1 - Der Einfluss von Verdauenzymen auf die Bioverfügbarkeit von Mykotoxinen T2 - 48. Wissenschaftlicher Kongress der Deutschen Gesellschaft für Ernährung CY - Potsdam, Germany DA - 2011-03-16 PY - 2011 AN - OPUS4-23320 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Köppen, Robert A1 - Koch, Matthias A1 - Siegel, David A1 - Merkel, Stefan A1 - Maul, Ronald A1 - Nehls, Irene T1 - Determination of mycotoxins in foods: current state of analytical methods and limitations N2 - Mycotoxins are natural contaminants produced by a range of fungal species. Their common occurrence in food and feed poses a threat to the health of humans and animals. This threat is caused either by the direct contamination of agricultural commodities or by a "carry-over" of mycotoxins and their metabolites into animal tissues, milk, and eggs after feeding of contaminated hay or corn. As a consequence of their diverse chemical structures and varying physical properties, mycotoxins exhibit a wide range of biological effects. Individual mycotoxins can be genotoxic, mutagenic, carcinogenic, teratogenic, and oestrogenic. To protect consumer health and to reduce economic losses, surveillance and control of mycotoxins in food and feed has become a major objective for producers, regulatory authorities and researchers worldwide. However, the variety of chemical structures makes it impossible to use one single technique for mycotoxin analysis. Hence, a vast number of analytical methods has been developed and validated. The heterogeneity of food matrices combined with the demand for a fast, simultaneous and accurate determination of multiple mycotoxins creates enormous challenges for routine analysis. The most crucial issues will be discussed in this review. These are (1) the collection of representative samples, (2) the performance of classical and emerging analytical methods based on chromatographic or immunochemical techniques, (3) the validation of official methods for enforcement, and (4) the limitations and future prospects of the current methods. KW - Mycotoxins and fungal metabolites KW - Food KW - Rapid and validated methods KW - Regulations KW - Sampling KW - Multi-mycotoxin determination PY - 2010 DO - https://doi.org/10.1007/s00253-010-2535-1 SN - 0175-7598 VL - 86 IS - 6 SP - 1595 EP - 1612 PB - Springer CY - Berlin AN - OPUS4-21184 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Verteilung von Fusarium-Mykotoxinen in Mahlpassagen T2 - 43. Deutscher Lebensmitelchemikertag CY - Gießen DA - 2014-09-22 PY - 2014 AN - OPUS4-31850 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Performance and Efficiency of Cleanup Columns for Selected Fusarium Mycotoxins and Conjugates T2 - ANAKON 2013 CY - Essen, Germany DA - 2013-03-04 PY - 2013 AN - OPUS4-27836 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - "Maskierte" Fusarium-Mykotoxine - Bildung und Auftreten im Lebensmittel T2 - Regionalverbandstagung Nordost der Lebensmitteltechnischen Gesellschaft CY - Berlin, Germany DA - 2013-03-14 PY - 2013 AN - OPUS4-27834 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kittler, Katrin A1 - Hoffmann, Holger A1 - Lindemann, Franziska A1 - Koch, Matthias A1 - Rohn, S. A1 - Maul, Ronald T1 - Biosynthesis of 15N-labeled cylindrospermopsin and its application as internal standard in stable isotope dilution analysis N2 - Cylindrospermopsin (CYN) is a cyanobacterial toxin associated with human and animal poisonings. Due to its toxicity in combination with its widespread occurrence, the development of reliable methods for selective, sensitive detection and accurate quantification is mandatory. Liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis using stable isotope dilution analysis (SIDA) represents an ideal tool for this purpose. U-[15N5]-CYN was synthesized by culturing Aphanizomenon flos-aquae in Na15NO3-containing cyanobacteria growth medium followed by a cleanup using graphitized carbon black columns and mass spectrometric characterization. Subsequently, a SIDA-LC-MS/MS method for the quantification of CYN in freshwater and Brassica matrices was developed showing satisfactory performance data. The recovery ranged between 98 and 103 %; the limit of quantification was 15 ng/L in freshwater and 50 µg/kg dry weight in Brassica samples. The novel SIDA was applied for CYN determination in real freshwater samples as well as in kale and in vegetable mustard exposed to toxin-containing irrigation water. Two of the freshwater samples taken from German lakes were found to be CYN-contaminated above limit of quantification (17.9 and 60.8 ng/L). CYN is systemically available to the examined vegetable species after exposure of the rootstock leading to CYN mass fractions in kale and vegetable mustard leaves of 15.0 µg/kg fresh weight and 23.9 µg/kg fresh weight, respectively. CYN measurements in both matrices are exemplary for the versatile applicability of the developed method in environmental analysis. KW - Cyanotoxin KW - Quantification KW - Surface water KW - Vegetable plants KW - SIDA KW - HPLC-MS/MS PY - 2014 DO - https://doi.org/10.1007/s00216-014-8026-y SN - 1618-2642 SN - 1618-2650 VL - 406 IS - 24 SP - 5765 EP - 5774 PB - Springer CY - Berlin AN - OPUS4-31566 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald T1 - Evaluierung und Validierung eines fluoreszenzpolarimetrischen Probenvorbereitungs- und Messverfahrens zur Mykotoxinanalyse T2 - ANAKON 2011 CY - Zurich, Switzerland DA - 2011-03-22 PY - 2011 AN - OPUS4-23319 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Dahmen-Levison, U. A1 - Koch, Matthias T1 - Mykotoxin-Cleanup mit Spin-Säulen - Evaluierung der Leistungsfähigkeit neuer Zentrifugationssäulen für die Analyse der Trichothecen-Mykotoxine DON, D3G, T2- und HT2-Toxin N2 - Mykotoxine sind toxische, von Schimmelpilzen gebildete Sekundärstoffe und gehören zu den am weitesten verbreiteten Lebensmittelkontaminanten. Trichtothecen-Mykotoxine, produziert von verschiedenen Fusarien-Spezies, sind dabei aufgrund ihrer hohen akuten Toxizität teils im Lebensmittel mit Grenzwerten geregelt oder befinden sich aktuell in einer entsprechenden Diskussion. PY - 2013 SN - 0012-0413 SN - 1869-2214 VL - 109 IS - März SP - 131 EP - 138 PB - Wiss. Verl.-Ges. CY - Stuttgart AN - OPUS4-28697 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Greer, B. A1 - Campbell, K. A1 - Elliott, C.T. T1 - Detection of freshwater cyanotoxins and measurement of masked microcystins in tilapia from Southeast Asian aquaculture farms N2 - Recently, there has been a rise in freshwater harmful algal blooms (HABs) globally, as well as increasing aquaculture practices. HABs can produce cyanotoxins, many of which are hepatotoxins. An ultra-performance liquid chromatography tandem mass spectrometry method was developed and validated for nine cyanotoxins across three classes including six microcystins, nodularin, cylindrospermopsin and anatoxin-a. The method was used to analyse free cyanotoxin(s) in muscle (n = 34), liver (n = 17) and egg (n = 9) tissue samples of 34 fish sourced from aquaculture farms in Southeast Asia. Conjugated microcystin was analysed by Lemieux oxidation to ascertain the total amount of microcystin present in muscle. Some tilapia accumulated free microcystin-LR in the muscle tissue at a mean of 15.45 μg/kg dry weight (dw), with total microcystin levels detected at a mean level of 110.1 μg/kg dw, indicating that the amount of conjugated or masked microcystin present in the fish muscle accounted for 85% of the total. Higher levels of cyanotoxin were detected in the livers, with approximately 60% of those tested being positive for microcystin-LR and microcystin-LF, along with cylindrospermopsin. Two fish from one of the aquaculture farms contained cylindrospermopsin in the eggs; the first time this has been reported. The estimated daily intake for free and total microcystins in fish muscle tissue was 2 and 14 times higher, respectively, than the tolerable daily intake value. This survey presents the requirement for further monitoring of cyanotoxins, including masked microcystins, in aquaculture farming in these regions and beyond, along with the implementation of guidelines to safeguard human health. KW - Harmful algal bloom KW - UPLC-MS/MS KW - Bioaccumulation KW - Human health PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-404669 DO - https://doi.org/10.1007/s00216-017-0352-4 SN - 1618-2642 SN - 1618-2650 VL - 409 IS - 16 SP - 4057 EP - 4069 PB - Springer CY - Heidelberg AN - OPUS4-40466 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schebb, N.H. A1 - Franze, B. A1 - Maul, Ronald A1 - Ranganathan, A. A1 - Hammock, B.D. T1 - In vitro glucuronidation of the antibacterial triclocarban and its oxidative metabolites N2 - Triclocarban (3,4,4'-trichlorocarbanilide; TCC) is widely used as an antibacterial in bar soaps. During use of these soaps, a significant portion of TCC is absorbed by humans. For the elimination from the body, glucuronidation plays a key role in both biliary and renal clearance. To investigate this metabolic pathway, we performed microsomal incubations of TCC and its hydroxylated metabolites 2'-OH-TCC, 3'-OH-TCC, and 6-OH-TCC. Using a new liquid chromatography-UV-mass spectrometry method, we could show a rapid glucuronidation for all OH-TCCs by the uridine-5'-diphosphate-glucuronosyltransferases (UGT) present in liver microsomes of humans (HLM), cynomolgus monkeys (CLM), rats (RLM), and mice (MLM). Among the tested human UGT isoforms, UGT1A7, UGT1A8, and UGT1A9 showed the highest activity for the conjugation of hydroxylated TCC metabolites followed by UGT1A1, UGT1A3, and UGT1A10. Due to this broad pattern of active UGTs, OH-TCCs can be efficiently glucuronidated in various tissues, as shown for microsomes from human kidney (HKM) and intestine (HIM). The major renal metabolites in humans, TCC-N-glucuronide and TCC-N'-glucuronide, were formed at very low conversion rates (<1%) by microsomal incubations. Low amounts of N-glucuronides were generated by HLM, HIM, and HKM, as well as by MLM and CLM, but not by RLM, according to the observed species specificity of this metabolic pathway. Among the human UGT isoforms, only UGT1A9 had activity for the N-glucuronidation of TCC. These results present an anomaly where in vivo the predominant urinary metabolites of TCC are N and N'-glucuronides, but these compounds are slowly produced in vitro. KW - 3,4,4'-trichlorocarbanilide KW - Metabolism KW - Glucuronidation PY - 2012 DO - https://doi.org/10.1124/dmd.111.042283 SN - 0090-9556 SN - 1521-009X VL - 40 IS - 1 SP - 25 EP - 31 PB - ASPET CY - Bethesda, Md., USA AN - OPUS4-25731 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dahmen-Levison, U. A1 - Maul, Ronald T1 - Kein kalter Kaffee - Eine schnelle, verlässliche Analysemethode für Ochratoxin: Validierung der Probenvorbereitung und Vorstellung der Analytik N2 - Ob Kaffee am Morgen, der Latte unterwegs oder der schnelle Espresso, Kaffee wird überall getrunken und ist das am häufigsten konsumierte Getränk in Deutschland. Schon seit Jahrhunderten lieben Menschen in der ganzen Welt dieses belebende Getränk. Es setzt sich aus ungefähr 1000 verschiedenen Inhaltsstoffen zusammen. Dazu gehören Vitamine und Mineralstoffe, Proteine und Fette, Säuren und Antioxidantien. Viele dieser Inhaltsstoffe können durchaus positive Effekte auf den menschlichen Organismus haben. PY - 2012 SN - 0012-0413 SN - 1869-2214 VL - 108 IS - April SP - 214 EP - 220 PB - Wiss. Verl.-Ges. CY - Stuttgart AN - OPUS4-26449 LA - deu 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 - TY - JOUR A1 - Maul, Ronald A1 - Warth, B. A1 - Kant, Jill-Sandra A1 - Schebb, N.H. A1 - Krska, R. A1 - Koch, Matthias A1 - Sulyok, M. T1 - Investigation of the hepatic glucuronidation pattern of the fusarium mycotoxin deoxynivalenol in various species N2 - Deoxynivalenol (DON) is one of the most abundant mycotoxins contaminating food and feed worldwide. Upon absorption, the major portion of the toxin is excreted by humans and animal species as glucuronide. However, consistent in vitro data on DON glucuronidation are lacking. In the present study, the metabolism of DON was investigated using liver microsomes from humans and six different animal species. It was shown that all animal and human liver microsomes led to the formation of up to three different mono-O-glucuronides with significant interspecies differences. While the activity of human liver microsomes was low (0.8 to 2.2 pmol·min–1·mg–1), bovine liver and rat liver microsomes conjugated DON with activities of 525 pmol·min–1·mg–1 and 80 pmol·min–1·mg–1, respectively. KW - Deoxynivalenol KW - Hepatic metabolism KW - Microsomes KW - Glucuronidation KW - Inter-species comparison PY - 2012 DO - https://doi.org/10.1021/tx300348x SN - 0893-228X SN - 1520-5010 VL - 25 IS - 12 SP - 2715 EP - 2717 PB - Soc. CY - Washington, DC, USA AN - OPUS4-27604 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 - Borzekowski, Antje A1 - Anggriawan, R. A1 - Auliyati, M. A1 - Kunte, Hans-Jörg A1 - Koch, Matthias A1 - Rohn, S. A1 - Karlovsky, P. A1 - Maul, Ronald T1 - Formation of Zearalenone Metabolites in Tempeh Fermentation N2 - Tempeh is a common food in Indonesia, produced by fungal fermentation of soybeans using Rhizopus sp., as well as Aspergillus oryzae, for inoculation. Analogously, for economic reasons, mixtures of maize and soybeans are used for the production of so-called tempeh-like products. For maize, a contamination with the mycoestrogen zearalenone (ZEN) has been frequently reported. ZEN is a mycotoxin which is known to be metabolized by Rhizopus and Aspergillus species. Consequently, this study focused on the ZEN transformation during tempeh fermentation. Five fungal strains of the genera Rhizopus and Aspergillus, isolated from fresh Indonesian tempeh and authentic Indonesian inocula, were utilized for tempeh manufacturing from a maize/soybean mixture (30:70) at laboratory-scale. Furthermore, comparable tempeh-like products obtained from Indonesian markets were analyzed. Results from the HPLC-MS/MS analyses show that ZEN is intensely transformed into its metabolites alpha-zearalenol (alpha-ZEL), ZEN-14-sulfate, alpha-ZEL-sulfate, ZEN-14-glucoside, and ZEN-16-glucoside in tempeh production. alpha-ZEL, being significantly more toxic than ZEN, was the main metabolite in most of the Rhizopus incubations, while in Aspergillus oryzae fermentations ZEN-14-sulfate was predominantly formed. Additionally, two of the 14 authentic samples were contaminated with ZEN, alpha-ZEL and ZEN-14-sulfate, and in two further samples, ZEN and alpha-ZEL, were determined. Consequently, tempeh fermentation of ZEN-contaminated maize/soybean mixture may lead to toxification of the food item by formation of the reductive ZEN metabolite, alpha-ZEL, under model as well as authentic conditions. KW - Modified mycotoxins KW - Zearalenone sulfate KW - a-zearalenol KW - Food fermentation KW - Rhizopus and Aspergillus oryzae PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-491126 DO - https://doi.org/10.3390/molecules24152697 VL - 24 IS - 15 SP - 2697 PB - MDPI AN - OPUS4-49112 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -