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 - Böhmert, L. A1 - Girod, Matthias A1 - Hansen, Ulf A1 - Maul, Ronald A1 - Knappe, Patrick A1 - Niemann, B. A1 - Weidner, Steffen A1 - Thünemann, Andreas A1 - Lampen, A. T1 - Analytically monitored digestion of silver nanoparticles and their toxicity on human intestinal cells N2 - Orally ingested nanoparticles may overcome the gastrointestinal barrier, reach the circulatory system, be distributed in the organism and cause adverse health effects. However, ingested nanoparticles have to pass through different physicochemical environments, which may alter their properties before they reach the intestinal cells. In this study, silver nanoparticles are characterised physicochemically during the course of artificial digestion to simulate the biochemical processes occurring during digestion. Their cytotoxicity on intestinal cells was investigated using the Caco-2 cell model. Using field-flow fractionation combined with dynamic light scattering and small-angle X-ray scattering, the authors found that particles only partially aggregate as a result of the digestive process. Cell viabilities were determined by means of CellTiter-Blue® assay, 4',6-diamidino-2-phenylindole-staining and real-time impedance. These measurements reveal small differences between digested and undigested particles (1–100 µg/ml or 1–69 particles/cell). The findings suggest that silver nanoparticles may indeed overcome the gastrointestinal juices in their particulate form without forming large quantities of aggregates. Consequently, the authors presume that the particles can reach the intestinal epithelial cells after ingestion with only a slight reduction in their cytotoxic potential. The study indicates that it is important to determine the impact of body fluids on the nanoparticles of interest to provide a reliable interpretation of their nano-specific cytotoxicity testing in vivo and in vitro. KW - Silver nanoparticles KW - In vitro digestion KW - Field-flow fractionation KW - Small-angle X-ray scattering KW - Dynamic light scattering KW - Caco-2 cells PY - 2014 DO - https://doi.org/10.3109/17435390.2013.815284 SN - 1743-5390 SN - 1743-5404 VL - 8 IS - 6 SP - 631 EP - 642 PB - Informa Healthcare CY - London AN - OPUS4-29926 LA - eng 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 -