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 - Esslinger, Susanne A1 - Becker, Roland A1 - Maul, Ronald A1 - Nehls, Irene T1 - Hexabromcyclododecan - Untersuchungen zum Phase I Metabolismus PY - 2010 SN - 0934-3504 SN - 1865-5084 VL - 22 IS - 4 SP - 364 PB - Springer CY - Heidelberg AN - OPUS4-22907 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maul, Ronald A1 - Dahmen-Levison, U. A1 - Koch, Matthias A1 - Panne, Ulrich 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 - 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 -