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Hans-ulrich Humpf - One of the best experts on this subject based on the ideXlab platform.
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Thermal stability of T-2 and HT-2 Toxins during biscuit- and crunchy muesli-making and roasting
Food additives & contaminants. Part A Chemistry analysis control exposure & risk assessment, 2018Co-Authors: Henning Sören Kuchenbuch, Stefanie Becker, Mareike Schulz, Benedikt Cramer, Hans-ulrich HumpfAbstract:The mycoToxins T-2 and HT-2 Toxin are frequently occurring food contaminants which are produced by Fusarium species. Humans and animals are mainly exposed to these substances by the consumption of contaminated oats, maize and wheat. For the production of crunchy muesli, bread and bakery products, these cereals undergo multiple processing steps, including baking, roasting and extrusion cooking. However, the influence of food processing on T-2 and HT-2 Toxin levels is to date poorly understood. Thus, the effects of baking and roasting on both mycoToxins were evaluated during biscuit-, crunchy muesli- and toasted oat flakes-production under precise variation of various parameters: heating time and temperature as well as recipe formulation were varied in the range they are applied in the food processing industry. Therefore, oatmeal or flaked oats were artificially contaminated individually with both Toxins and processed at the laboratory scale. T-2 Toxin generally showed a higher degradation rate than HT-2 Toxin. During biscuit-making up to 45% of T-2 Toxin and 20% of HT-2 Toxin were thermally degraded, showing a dependency on water content, baking time and temperature. The preparation of crunchy muesli yielded no significant Toxin degradation which is probably due to the low temperatures applied. Roasting led to a degradation of 32% of T-2 Toxin and 24% of HT-2 Toxin. Taken together, both mycoToxins are partially degraded during thermal food processing; the degradation rates are influenced by the food composition and processing parameters.
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A comparative study of the human urinary mycoToxin excretion patterns in Bangladesh, Germany, and Haiti using a rapid and sensitive LC-MS/MS approach
Mycotoxin Research, 2015Co-Authors: Johannes Gerding, Benedikt Cramer, Nurshad Ali, Jeremy Schwartzbord, Dan L. Brown, Gisela H. Degen, Hans-ulrich HumpfAbstract:An improved “dilute and shoot” LC-MS/MS multibiomarker approach was used to monitor urinary excretion of 23 mycoToxins and their metabolites in human populations from Asia (Bangladesh), Europe (Germany), and the Caribbean region (Haiti). Deoxynivalenol (DON), deoxynivalenol-3-glucuronide (DON-3-GlcA), T-2-Toxin (T-2), HT-2-Toxin (HT-2), HT-2-Toxin-4-glucuronide (HT-2-4-GlcA), fumonisin B_1 (FB_1), aflaToxins (AFB_1, AFB_2, AFG_1, AFG_2, AFM_1), zearalenone (ZEA), zearalanone (ZAN), their urinary metabolites α-zearalanol (α-ZEL) and β-zearalanol (β-ZEL), and corresponding 14-O-glucuronic acid conjugates (ZEA-14-GlcA, ZAN-14-GlcA, β-ZEL, α/β–ZEL-14-GlcA), ochraToxin A (OTA), and ochraToxin alpha (OT_α) as well as enniatin B (EnB) and dihydrocitrinone (DH-CIT) were among these compounds. EigHT urinary mycoToxin biomarkers were detected (AFM_1, DH-CIT, DON, DON-GLcA, EnB, FB_1, OTA, and α-ZEL). DON and DON-GlcA were exclusively detected in urines from Germany and Haiti whereas urinary OTA and DH-CIT concentrations were significantly higher in Bangladeshi samples. AFM_1 was present in samples from Bangladesh and Haiti only. Exposure was estimated by the calculation of probable daily intakes (PDI), and estimates suggested occasional instances of Toxin intakes that exceed established tolerable daily intakes (TDI). The detection of individual mycoToxin exposure by biomarker-based approaches is a meaningful addition to the classical monitoring of the mycoToxin content of the food supply.
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influence of t 2 and HT 2 Toxin on the blood brain barrier in vitro new experimental hints for neurotoxic effects
PLOS ONE, 2013Co-Authors: Maria Weidner, Sabine Huwel, Franziska Ebert, Tanja Schwerdtle, Hansjoachim Galla, Hans-ulrich HumpfAbstract:The trichothecene mycoToxin T-2 Toxin is a common contaminant of food and feed and is also present in processed cereal derived products. Cytotoxic effects of T-2 Toxin and its main metabolite HT-2 Toxin are already well described with apoptosis being a major mechanism of action. However, effects on the central nervous system were until now only reported rarely. In this study we investigated the effects of T-2 and HT-2 Toxin on the blood-brain barrier (BBB) in vitro. Besides strong cytotoxic effects on the BBB as determined by the CCK-8 assay, impairment of the barrier function starting at low nanomolar concentrations were observed for T-2 Toxin. HT-2 Toxin, however, caused barrier disruption at higher concentrations compared to T-2 Toxin. Further, the influence on the tigHT junction protein occludin was studied and permeability of both Toxins across the BBB was detected when applied from the apical (blood) or the basolateral (brain) side respectively. These results clearly indicate the ability of both Toxins to enter the brain via the BBB.
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HT-2 Toxin 4-Glucuronide as New T-2 Toxin Metabolite: Enzymatic Synthesis, Analysis, and Species Specific Formation of T-2 and HT-2 Toxin Glucuronides by Rat, Mouse, Pig, and Human Liver Microsomes
Journal of Agricultural and Food Chemistry, 2012Co-Authors: Tanja Welsch, Hans-ulrich HumpfAbstract:Glucuronides of the mycoToxin T-2 Toxin and its phase I metabolite HT-2 Toxin are important phase II metabolites under in vivo and in vitro conditions. Since standard substances are essential for the direct quantitation of these glucuronides, a method for the enzymatic synthesis of T-2 and HT-2 Toxin glucuronides employing liver microsomes was optimized. Structure elucidation by nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry revealed that besides T-2 Toxin glucuronide and HT-2 Toxin 3-glucuronide also the newly identified isomer HT-2 Toxin 4-glucuronide was formed. Glucuronidation of T-2 and HT-2 Toxin in liver microsomes of rat, mouse, pig, and human was compared and metabolites were analyzed directly by liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS). A distinct, species specific pattern of glucuronidation of T-2 and HT-2 Toxin was observed with interesting interindividual differences. Until recently, glucuronides have frequently been analyzed indirectly by qu...
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Identification and apoptotic potential of T-2 Toxin metabolites in human cells.
Journal of Agricultural and Food Chemistry, 2012Co-Authors: Maria Weidner, Michael Gekle, Gerald Schwerdt, Tanja Welsch, Florian Hübner, Hans-ulrich HumpfAbstract:The mycoToxin T-2 Toxin, produced by various Fusarium species, is a widespread contaminant of grain and grain products. Knowledge about its toxicity and metabolism in the human body is crucial for any risk assessment as T-2 Toxin can be detected in processed and unprocessed food samples. Cell culture studies using cells of human origin represent a potent model system to study the metabolic fate of T-2 Toxin as well as the cytotoxicity in vitro. In this study the metabolism of T-2 Toxin was analyzed in a cell line derived from human colon carcinoma cells (HT-29) and primary human renal proximal tubule epithelial cells (RPTEC) using high-performance liquid chromatography coupled with Fourier transformation mass spectrometry (HPLC-FTMS). Both cell types metabolized T-2 Toxin to a variety of compounds. Furthermore, cell cycle analysis in RPTEC proved the apoptotic effect of T-2 Toxin and its metabolites HT-2 Toxin and neosolaniol in micromolar concentrations. © 2012 American Chemical Society.
Gerhard Adam - One of the best experts on this subject based on the ideXlab platform.
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tracing the metabolism of HT 2 Toxin and t 2 Toxin in barley by isotope assisted untargeted screening and quantitative lc hrms analysis
Analytical and Bioanalytical Chemistry, 2015Co-Authors: Jacqueline Mengreiterer, Herbert Michlmayr, Elisabeth Varga, Alexandra Malachová, Philipp Fruhmann, Alexis V Nathanail, Christoph Bueschl, Justyna Rechthaler, Susan P Mccormick, Gerhard AdamAbstract:An extensive study of the metabolism of the type A trichothecene mycoToxins HT-2 Toxin and T-2 Toxin in barley using liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) is reported. A recently developed untargeted approach based on stable isotopic labelling, LC-Orbitrap-MS analysis with fast polarity switching and data processing by MetExtract software was combined with targeted LC-Q-TOF-MS(/MS) analysis for metabolite structure elucidation and quantification. In total, 9 HT-2 Toxin and 13 T-2 Toxin metabolites plus tentative isomers were detected, which were successfully annotated by calculation of elemental formulas and further LC-HRMS/MS measurements as well as partly identified with authentic standards. As a result, glucosylated forms of the Toxins, malonylglucosides, and acetyl and feruloyl conjugates were elucidated. Additionally, time courses of metabolite formation and mass balances were established. For absolute quantification of those compounds for which standards were available, the method was validated by determining apparent recovery, signal suppression, or enhancement and extraction recovery. Most importantly, T-2 Toxin was rapidly metabolised to HT-2 Toxin and for both parent Toxins HT-2 Toxin-3-O-β-glucoside was identified (confirmed by authentic standard) as the main metabolite, which reached its maximum already 1 day after Toxin treatment.
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metabolism of the fusarium mycoToxins t 2 Toxin and HT 2 Toxin in wheat
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Alexis V Nathanail, Herbert Michlmayr, Elisabeth Varga, Alexandra Malachová, Philipp Fruhmann, Jacqueline Mengreiterer, Christoph Bueschl, Marika Jestoi, Kimmo Peltonen, Gerhard AdamAbstract:To investigate the metabolic fate of HT-2 Toxin (HT2) and T-2 Toxin (T2) in wheat (Triticum aestivum L.), an untargeted metabolomics study utilizing stable isotopic labeling and liquid chromatography–high resolution mass spectrometry was performed. In total, 11 HT2 and 12 T2 derived in planta biotransformation products were annotated putatively. In addition to previously reported mono- and diglucosylated forms of HT2, evidence for the formation of HT2-malonyl-glucoside and feruloyl-T2, as well as acetylation and deacetylation products in wheat was obtained for the first time. To monitor the kinetics of metabolite formation, a time course experiment was conducted involving the Fusarium head bligHT susceptible variety Remus and the resistant cultivar CM-82036. Biotransformation reactions were observed already at the earliest tested time point (6 h after treatment), and formed metabolites showed different kinetic profiles. After ripening, less than 15% of the Toxins added to the plants were determined to be ...
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a versatile family 3 glycoside hydrolase from bifidobacterium adolescentis hydrolyzes β glucosides of the fusarium mycoToxins deoxynivalenol nivalenol and HT 2 Toxin in cereal matrices
Applied and Environmental Microbiology, 2015Co-Authors: Herbert Michlmayr, Franz Berthiller, Elisabeth Varga, Alexandra Malachová, Nhung Thi Nguyen, Cindy Lorenz, Dietmar Haltrich, Gerhard AdamAbstract:Glycosylation plays a central role in plant defense against xenobiotics, including mycoToxins. Glucoconjugates of Fusarium Toxins, such as deoxynivalenol-3-O-β-d-glucoside (DON-3G), often cooccur with their parental Toxins in cereal-based food and feed. To date, only limited information exists on the occurrence of glucosylated mycoToxins and their toxicological relevance. Due to a lack of analytical standards and the requirement of high-end analytical instrumentation for their direct determination, hydrolytic cleavage of β-glucosides followed by analysis of the released parental Toxins has been proposed as an indirect determination approach. This study compares the abilities of several fungal and recombinant bacterial β-glucosidases to hydrolyze the model analyte DON-3G. Furthermore, substrate specificities of two fungal and two bacterial (Lactobacillus brevis and Bifidobacterium adolescentis) glycoside hydrolase family 3 β-glucosidases were evaluated on a broader range of substrates. The purified recombinant enzyme from B. adolescentis (BaBgl) displayed high flexibility in substrate specificity and exerted the highest hydrolytic activity toward 3-O-β-d-glucosides of the trichothecenes deoxynivalenol (DON), nivalenol, and HT-2 Toxin. A Km of 5.4 mM and a Vmax of 16 μmol min−1 mg−1 were determined with DON-3G. Due to low product inhibition (DON and glucose) and sufficient activity in several extracts of cereal matrices, this enzyme has the potential to be used for indirect analyses of trichothecene-β-glucosides in cereal samples.
Aref Eldemerdash - One of the best experts on this subject based on the ideXlab platform.
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a collaborative study determination of mycoToxins in corn peanut butter and wheat flour using stable isotope dilution assay sida and liquid chromatography tandem mass spectrometry lc ms ms
Journal of Agricultural and Food Chemistry, 2017Co-Authors: Kai Zhang, Matthew R Schaab, Gavin Southwood, Linda S Aston, Wenlu Song, Brian D Eitzer, Sanghamitra Majumdar, Theodore Lapainis, Kevin Tran, Aref EldemerdashAbstract:A collaborative study was conducted to evaluate stable isotope dilution assay (SIDA) and LC-MS/MS for the simultaneous determination of aflaToxins B1, B2, G1, and G2; deoxynivalenol; fumonisins B1, B2, and B3; ochraToxin A; HT-2 Toxin; T-2 Toxin; and zearalenone in foods. Samples were fortified with 12 13C uniformly labeled mycoToxins (13C-IS) corresponding to the native mycoToxins and extracted with acetonitrile/water (50:50 v/v), followed by centrifugation, filtration, and LC-MS/MS analysis. In addition to certified reference materials, the six participating laboratories analyzed corn, peanut butter, and wheat flour fortified with the 12 mycoToxins at concentrations ranging from 1.0 to 1000 ng/g. Using their available LC-MS/MS platform, each laboratory developed in-house instrumental conditions for analysis. The majority of recoveries ranged from 80 to 120% with relative standard derivations (RSDs) <20%. Greater than 90% of the average recoveries of the participating laboratories were in the range of 90...
Jacqueline Mengreiterer - One of the best experts on this subject based on the ideXlab platform.
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metabolism of HT 2 Toxin and t 2 Toxin in oats
Toxins, 2016Co-Authors: Jacqueline Mengreiterer, Franz Berthiller, Marc Lemmens, Christoph Bueschl, Justyna Rechthaler, Rainer SchuhmacherAbstract:The Fusarium mycoToxins HT-2 Toxin (HT2) and T-2 Toxin (T2) are frequent contaminants in oats. These Toxins, but also their plant metabolites, may contribute to toxicological effects. This work describes the use of 13C-assisted liquid chromatography–high-resolution mass spectrometry for the first comprehensive study on the biotransformation of HT2 and T2 in oats. Using this approach, 16 HT2 and 17 T2 metabolites were annotated including novel glycosylated and hydroxylated forms of the Toxins, hydrolysis products, and conjugates with acetic acid, putative malic acid, malonic acid, and ferulic acid. Further targeted quantitative analysis was performed to study Toxin metabolism over time, as well as Toxin and conjugate mobility within non-treated plant tissues. As a result, HT2-3-O-β-d-glucoside was identified as the major detoxification product of both parent Toxins, which was rapidly formed (to an extent of 74% in HT2-treated and 48% in T2-treated oats within one day after treatment) and further metabolised. Mobility of the parent Toxins appeared to be negligible, while HT2-3-O-β-d-glucoside was partly transported (up to approximately 4%) through panicle side branches and stem. Our findings demonstrate that the presented combination of untargeted and targeted analysis is well suited for the comprehensive elucidation of mycoToxin metabolism in plants.
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tracing the metabolism of HT 2 Toxin and t 2 Toxin in barley by isotope assisted untargeted screening and quantitative lc hrms analysis
Analytical and Bioanalytical Chemistry, 2015Co-Authors: Jacqueline Mengreiterer, Herbert Michlmayr, Elisabeth Varga, Alexandra Malachová, Philipp Fruhmann, Alexis V Nathanail, Christoph Bueschl, Justyna Rechthaler, Susan P Mccormick, Gerhard AdamAbstract:An extensive study of the metabolism of the type A trichothecene mycoToxins HT-2 Toxin and T-2 Toxin in barley using liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) is reported. A recently developed untargeted approach based on stable isotopic labelling, LC-Orbitrap-MS analysis with fast polarity switching and data processing by MetExtract software was combined with targeted LC-Q-TOF-MS(/MS) analysis for metabolite structure elucidation and quantification. In total, 9 HT-2 Toxin and 13 T-2 Toxin metabolites plus tentative isomers were detected, which were successfully annotated by calculation of elemental formulas and further LC-HRMS/MS measurements as well as partly identified with authentic standards. As a result, glucosylated forms of the Toxins, malonylglucosides, and acetyl and feruloyl conjugates were elucidated. Additionally, time courses of metabolite formation and mass balances were established. For absolute quantification of those compounds for which standards were available, the method was validated by determining apparent recovery, signal suppression, or enhancement and extraction recovery. Most importantly, T-2 Toxin was rapidly metabolised to HT-2 Toxin and for both parent Toxins HT-2 Toxin-3-O-β-glucoside was identified (confirmed by authentic standard) as the main metabolite, which reached its maximum already 1 day after Toxin treatment.
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metabolism of the fusarium mycoToxins t 2 Toxin and HT 2 Toxin in wheat
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Alexis V Nathanail, Herbert Michlmayr, Elisabeth Varga, Alexandra Malachová, Philipp Fruhmann, Jacqueline Mengreiterer, Christoph Bueschl, Marika Jestoi, Kimmo Peltonen, Gerhard AdamAbstract:To investigate the metabolic fate of HT-2 Toxin (HT2) and T-2 Toxin (T2) in wheat (Triticum aestivum L.), an untargeted metabolomics study utilizing stable isotopic labeling and liquid chromatography–high resolution mass spectrometry was performed. In total, 11 HT2 and 12 T2 derived in planta biotransformation products were annotated putatively. In addition to previously reported mono- and diglucosylated forms of HT2, evidence for the formation of HT2-malonyl-glucoside and feruloyl-T2, as well as acetylation and deacetylation products in wheat was obtained for the first time. To monitor the kinetics of metabolite formation, a time course experiment was conducted involving the Fusarium head bligHT susceptible variety Remus and the resistant cultivar CM-82036. Biotransformation reactions were observed already at the earliest tested time point (6 h after treatment), and formed metabolites showed different kinetic profiles. After ripening, less than 15% of the Toxins added to the plants were determined to be ...
Lorenzo Covarelli - One of the best experts on this subject based on the ideXlab platform.
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presence of fusarium species and other toxigenic fungi in malting barley and multi mycoToxin analysis by liquid chromatography high resolution mass spectrometry
Journal of Agricultural and Food Chemistry, 2016Co-Authors: Giovanni Beccari, Leonardo Caproni, Francesco Tini, Silvio Uhlig, Lorenzo CovarelliAbstract:A study was carried out on 43 malting barley samples collected in 2013 across the Umbria region (central Italy) to determine the incidence of the principal mycotoxigenic fungal genera, to identify the Fusarium species isolated from the grains, and to detect the presence of 34 fungal secondary metabolites by liquid chromatography–high-resolution mass spectrometry. The multimycoToxin-method development involved the evaluation of both a two-step solvent and QuEChERS protocol for metabolite extraction. The former protocol was selected because of better accuracy, which was evaluated on the basis of spike-recovery experiments. The most frequently isolated fungal species belonged to the genera Alternaria and Fusarium. The predominant Fusarium species was F. avenaceum, followed by F. graminearum. HT-2 Toxin was the most frequently detected mycoToxin, followed by enniatin B, enniatin B1, T-2 Toxin, and nivalenol. As a consequence of the observed mixed fungal infections, mycoToxin co-occurrence was also detected. A...