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Christian Zwiener - One of the best experts on this subject based on the ideXlab platform.
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Identification of transformation products of Denatonium - Occurrence in wastewater treatment plants and surface waters.
Science of The Total Environment, 2019Co-Authors: Sascha Lege, Anna Eisenhofer, Jorge Eduardo Yanez Heras, Christian ZwienerAbstract:Denatonium, one of the bitterest substances known to man, was recently identified as wastewater borne micropollutant in surface waters. Therefore, photodegradation experiments and electrochemical degradation were performed to identify abiotic and putative biotic transformation products (TPs). Indirect rather than direct photodegradation proved to be important for Denatonium removal by solar irradiation and produced seven TPs. Amide hydrolysis, hydroxylation, N-dealkylation, and N-dearylation were revealed as the main mechanisms. Anodic oxidation of Denatonium was related to the formation of overall ten products and despite considerable different yields, all TPs from indirect photodegradation were mimicked electrochemically. Among them, lidocaine was the only TP detected after conventional wastewater treatment and in surface waters. The occurrence of lidocaine was however associated with its application as local anesthetic rather than to a degradation of Denatonium. The absence of additional products suggests that Denatonium degradation is negligible under environmental conditions, supporting the previously described persistent nature of this compound. Advanced water treatment techniques however have the potential to degrade Denatonium. About 74% of the initial Denatonium load was removed from wastewater during pilot-scale ozonation. The degradation of Denatonium was accompanied here with the formation of at least two polar products, which are passing unchanged through a sand filter after ozonation. Both substances have completely unknown (toxicological) properties and this study seems to be the first report about their structures in general, as none of them was found in any of the large compound libraries (e.g. PubChem).
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Denatonium a so far unrecognized but ubiquitous water contaminant
Water Research, 2017Co-Authors: Sascha Lege, Sylvain Merel, Jorge Eduardo Yanez Heras, Gaelle Guillet, Christian ZwienerAbstract:Denatonium is one of the bitterest substances known to man and therefore applied in numerous consumer products to prevent an accidental or intentional consumption. So far no information was available on the occurrence of this compound in the environment. A sensitive targeted method was developed and applied to water samples taken in the federal state of Baden-Wurttemberg, Germany. Denatonium was detected in 100% of the investigated 22 wastewater treatment plant (WWTP) effluents with a maximum concentration of 341 ng L-1. Additionally, water samples were taken from the Ammer river over a period of one week and all wastewater impacted samples showed Denatonium at concentrations up to 195 ng L-1. Retrospective analysis of high-resolution mass spectrometric measurements of WWTP effluents from Italy and Switzerland confirmed and therefore point to an international occurrence of Denatonium as anthropogenic contaminant.
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Denatonium – A so far unrecognized but ubiquitous water contaminant?
Water Research, 2017Co-Authors: Sascha Lege, Jorge Eduardo Yanez Heras, Sylvain Merel, Gérard Guillet, Christian ZwienerAbstract:Denatonium is one of the bitterest substances known to man and therefore applied in numerous consumer products to prevent an accidental or intentional consumption. So far no information was available on the occurrence of this compound in the environment. A sensitive targeted method was developed and applied to water samples taken in the federal state of Baden-W�rttemberg, Germany. Denatonium was detected in 100% of the investigated 22 wastewater treatment plant (WWTP) effluents with a maximum concentration of 341�ng�L−1. Additionally, water samples were taken from the Ammer river over a period of one week and all wastewater impacted samples showed Denatonium at concentrations up to 195�ng�L−1. Retrospective analysis of high-resolution mass spectrometric measurements of WWTP effluents from Italy and Switzerland confirmed and therefore point to an international occurrence of Denatonium as anthropogenic contaminant.
Sascha Lege - One of the best experts on this subject based on the ideXlab platform.
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Identification of transformation products of Denatonium - Occurrence in wastewater treatment plants and surface waters.
Science of The Total Environment, 2019Co-Authors: Sascha Lege, Anna Eisenhofer, Jorge Eduardo Yanez Heras, Christian ZwienerAbstract:Denatonium, one of the bitterest substances known to man, was recently identified as wastewater borne micropollutant in surface waters. Therefore, photodegradation experiments and electrochemical degradation were performed to identify abiotic and putative biotic transformation products (TPs). Indirect rather than direct photodegradation proved to be important for Denatonium removal by solar irradiation and produced seven TPs. Amide hydrolysis, hydroxylation, N-dealkylation, and N-dearylation were revealed as the main mechanisms. Anodic oxidation of Denatonium was related to the formation of overall ten products and despite considerable different yields, all TPs from indirect photodegradation were mimicked electrochemically. Among them, lidocaine was the only TP detected after conventional wastewater treatment and in surface waters. The occurrence of lidocaine was however associated with its application as local anesthetic rather than to a degradation of Denatonium. The absence of additional products suggests that Denatonium degradation is negligible under environmental conditions, supporting the previously described persistent nature of this compound. Advanced water treatment techniques however have the potential to degrade Denatonium. About 74% of the initial Denatonium load was removed from wastewater during pilot-scale ozonation. The degradation of Denatonium was accompanied here with the formation of at least two polar products, which are passing unchanged through a sand filter after ozonation. Both substances have completely unknown (toxicological) properties and this study seems to be the first report about their structures in general, as none of them was found in any of the large compound libraries (e.g. PubChem).
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Denatonium a so far unrecognized but ubiquitous water contaminant
Water Research, 2017Co-Authors: Sascha Lege, Sylvain Merel, Jorge Eduardo Yanez Heras, Gaelle Guillet, Christian ZwienerAbstract:Denatonium is one of the bitterest substances known to man and therefore applied in numerous consumer products to prevent an accidental or intentional consumption. So far no information was available on the occurrence of this compound in the environment. A sensitive targeted method was developed and applied to water samples taken in the federal state of Baden-Wurttemberg, Germany. Denatonium was detected in 100% of the investigated 22 wastewater treatment plant (WWTP) effluents with a maximum concentration of 341 ng L-1. Additionally, water samples were taken from the Ammer river over a period of one week and all wastewater impacted samples showed Denatonium at concentrations up to 195 ng L-1. Retrospective analysis of high-resolution mass spectrometric measurements of WWTP effluents from Italy and Switzerland confirmed and therefore point to an international occurrence of Denatonium as anthropogenic contaminant.
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Denatonium – A so far unrecognized but ubiquitous water contaminant?
Water Research, 2017Co-Authors: Sascha Lege, Jorge Eduardo Yanez Heras, Sylvain Merel, Gérard Guillet, Christian ZwienerAbstract:Denatonium is one of the bitterest substances known to man and therefore applied in numerous consumer products to prevent an accidental or intentional consumption. So far no information was available on the occurrence of this compound in the environment. A sensitive targeted method was developed and applied to water samples taken in the federal state of Baden-W�rttemberg, Germany. Denatonium was detected in 100% of the investigated 22 wastewater treatment plant (WWTP) effluents with a maximum concentration of 341�ng�L−1. Additionally, water samples were taken from the Ammer river over a period of one week and all wastewater impacted samples showed Denatonium at concentrations up to 195�ng�L−1. Retrospective analysis of high-resolution mass spectrometric measurements of WWTP effluents from Italy and Switzerland confirmed and therefore point to an international occurrence of Denatonium as anthropogenic contaminant.
Sylvain Merel - One of the best experts on this subject based on the ideXlab platform.
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Denatonium a so far unrecognized but ubiquitous water contaminant
Water Research, 2017Co-Authors: Sascha Lege, Sylvain Merel, Jorge Eduardo Yanez Heras, Gaelle Guillet, Christian ZwienerAbstract:Denatonium is one of the bitterest substances known to man and therefore applied in numerous consumer products to prevent an accidental or intentional consumption. So far no information was available on the occurrence of this compound in the environment. A sensitive targeted method was developed and applied to water samples taken in the federal state of Baden-Wurttemberg, Germany. Denatonium was detected in 100% of the investigated 22 wastewater treatment plant (WWTP) effluents with a maximum concentration of 341 ng L-1. Additionally, water samples were taken from the Ammer river over a period of one week and all wastewater impacted samples showed Denatonium at concentrations up to 195 ng L-1. Retrospective analysis of high-resolution mass spectrometric measurements of WWTP effluents from Italy and Switzerland confirmed and therefore point to an international occurrence of Denatonium as anthropogenic contaminant.
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Denatonium – A so far unrecognized but ubiquitous water contaminant?
Water Research, 2017Co-Authors: Sascha Lege, Jorge Eduardo Yanez Heras, Sylvain Merel, Gérard Guillet, Christian ZwienerAbstract:Denatonium is one of the bitterest substances known to man and therefore applied in numerous consumer products to prevent an accidental or intentional consumption. So far no information was available on the occurrence of this compound in the environment. A sensitive targeted method was developed and applied to water samples taken in the federal state of Baden-W�rttemberg, Germany. Denatonium was detected in 100% of the investigated 22 wastewater treatment plant (WWTP) effluents with a maximum concentration of 341�ng�L−1. Additionally, water samples were taken from the Ammer river over a period of one week and all wastewater impacted samples showed Denatonium at concentrations up to 195�ng�L−1. Retrospective analysis of high-resolution mass spectrometric measurements of WWTP effluents from Italy and Switzerland confirmed and therefore point to an international occurrence of Denatonium as anthropogenic contaminant.
Robert F. Margolskee - One of the best experts on this subject based on the ideXlab platform.
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Increased taste nerve responses to sweet and bitter stimuli in Gli3CKO mice.
2018Co-Authors: Yumei Qin, Sunil K. Sukumaran, Masafumi Jyotaki, Kevin Redding, Peihua Jiang, Robert F. MargolskeeAbstract:Average glossopharyngeal (GL) nerve responses to sweet (sucrose and sucralose, A and B), umami (monosodium glutamate [MSG], C), bitter (Denatonium, D), salty (NaCl, E), and sour (citric acid, F) tasting compounds are shown. The magnitude of the responses to taste compounds was normalized against the response to 100 mM NH4Cl. Compared to Gli3WT mice, Gli3CKO mice exhibit increased nerve responses to sucrose, sucralose, and Denatonium across a range of concentrations, while the responses to other stimuli were unaffected. Statistically significant differences were determined by repeated two-way ANOVA test [sucrose: F (1, 63) = 12.32, P0.05] and post hoc t-test (n≥7, *p
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Gli3-deficient mice exhibit increased behavioral responses to sweet, umami, and bitter tastants.
2018Co-Authors: Yumei Qin, Sunil K. Sukumaran, Masafumi Jyotaki, Kevin Redding, Peihua Jiang, Robert F. MargolskeeAbstract:Brief-access tests were used to measure behavioral responses to sweet (sucrose and sucralose, A and B), umami (monosodium glutamate [MSG], C), bitter (Denatonium, D), salty (NaCl, E), and sour (citric acid, F) taste stimuli. Compared to Gli3WT mice, Gli3CKO mice display increased lick responses over a range of concentrations to the appetitive stimuli (sucrose, sucralose, and MSG) and decreased lick responses to the aversive stimuli (Denatonium and citric acid). Lick ratios were calculated by dividing the number of licks to a taste solution by the number of licks to water in each test session. Data are means ± SEM Statistically significant differences were determined by repeated two-way ANOVA test [sucrose: F (1, 119) = 13.07, P
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Taste Receptor Cell Responses to the Bitter Stimulus Denatonium Involve Ca2+ Influx Via Store-Operated Channels
Journal of Neurophysiology, 2002Co-Authors: Tatsuya Ogura, Robert F. Margolskee, Sue C KinnamonAbstract:Previous studies in rat and mouse have shown that brief exposure to the bitter stimulus Denatonium induces an increase in [Ca2+]i due to Ca2+ release from intracellular Ca2+ stores, rather than Ca2...
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Gγ13 colocalizes with gustducin in taste receptor cells and mediates IP_3 responses to bitter Denatonium
Nature Neuroscience, 1999Co-Authors: Liquan Huang, Y. Gopi Shanker, Jolanta Dubauskaite, Jenny Z. Zheng, Wentao Yan, Sophia Rosenzweig, Andrew I. Spielman, Marianna Max, Robert F. MargolskeeAbstract:Gustducin is a transducin-like G protein selectively expressed in taste receptor cells. The α subunit of gustducin (α-gustducin) is critical for transduction of responses to bitter or sweet compounds. We identified a G-protein γ subunit (Gγ13) that colocalized with α-gustducin in taste receptor cells. Of 19 α-gustducin/Gγ13-positive taste receptor cells profiled, all expressed the G protein β3 subunit (Gβ3); ~80% also expressed Gβ1. Gustducin heterotrimers (α-gustducin/Gβ1/Gγ13) were activated by taste cell membranes plus bitter Denatonium. Antibodies against Gγ13 blocked the Denatonium-induced increase of inositol trisphosphate (IP_3) in taste tissue. We conclude that gustducin heterotrimers transduce responses to bitter and sweet compounds via α-gustducin's regulation of phosphodiesterase (PDE) and Gβγ's activation of phospholipase C (PLC).
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Ggamma13 colocalizes with gustducin in taste receptor cells and mediates IP3 responses to bitter Denatonium.
Nature Neuroscience, 1999Co-Authors: Liquan Huang, Wentao Yan, Marianna Max, Dubauskaite J, Rosenzweig S, Robert F. MargolskeeAbstract:Gustducin is a transducin-like G protein selectively expressed in taste receptor cells. The alpha subunit of gustducin (alpha-gustducin) is critical for transduction of responses to bitter or sweet compounds. We identified a G-protein gamma subunit (Ggamma13) that colocalized with alpha-gustducin in taste receptor cells. Of 19 alpha-gustducin/Ggamma13-positive taste receptor cells profiled, all expressed the G protein beta3 subunit (Gbeta3); approximately 80% also expressed Gbeta1. Gustducin heterotrimers (alpha-gustducin/Gbeta1/Ggamma13) were activated by taste cell membranes plus bitter Denatonium. Antibodies against Ggamma13 blocked the Denatonium-induced increase of inositol trisphosphate (IP3) in taste tissue. We conclude that gustducin heterotrimers transduce responses to bitter and sweet compounds via alpha-gustducin's regulation of phosphodiesterase (PDE) and Gbetagamma's activation of phospholipase C (PLC).
Carolina Sorto Castañon - One of the best experts on this subject based on the ideXlab platform.
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new Denatonium benzoate tin heterogeneous catalyst to obtain biodiesel via low temperature transesterification process lttp
Advanced Materials Research, 2010Co-Authors: Pio Sifuentes Gallardo, Angélica Silvestre López Rodríguez, Laura Lorena Díaz Flores, Miguel Ángel Hernández Rivera, L Ramos F De Valle, Carolina Sorto CastañonAbstract:Biodiesel was synthesized using waste chicken oil and ethyl alcohol as reactives as well as Denatonium benzoate and tin particles as catalysts in 500 mL three neck flask. The reaction mixtures were mechanically stirred at 200 rpm during 15 minutes at 30, 40, 50, y 60 o C, after that the products were filtered trough a 400 m mesh an then casted in a separating funnel in order to obtain two layers corresponding to glycerol and Biodiesel. The tin catalyst particles were observed by optical microscopy. The biodiesel and glycerol were characterized using refractive index, pH, Fourier transformer infrared spectrometry (FTIR), while the viscosity was determined in a Brookfield viscosimeter and density using a picnometer. The results suggest that at a low concentration of denatonuim benzoate (7 ppm) the reaction will occur only if tin is present at all test temperatures. The pH of biodiesel obtained was 6, similar to petrodiesel used commonly in diesel motors.
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New Denatonium Benzoate/tin Heterogeneous Catalyst to Obtain Biodiesel via Low Temperature Transesterification Process(LTTP)
Advanced Materials Research, 2010Co-Authors: Pio Sifuentes Gallardo, Angélica Silvestre López Rodríguez, Laura Lorena Díaz Flores, Miguel Ángel Hernández Rivera, L.f. Ramos De Valle, Carolina Sorto CastañonAbstract:Biodiesel was synthesized using waste chicken oil and ethyl alcohol as reactives as well as Denatonium benzoate and tin particles as catalysts in 500 mL three neck flask. The reaction mixtures were mechanically stirred at 200 rpm during 15 minutes at 30, 40, 50, y 60 o C, after that the products were filtered trough a 400 m mesh an then casted in a separating funnel in order to obtain two layers corresponding to glycerol and Biodiesel. The tin catalyst particles were observed by optical microscopy. The biodiesel and glycerol were characterized using refractive index, pH, Fourier transformer infrared spectrometry (FTIR), while the viscosity was determined in a Brookfield viscosimeter and density using a picnometer. The results suggest that at a low concentration of denatonuim benzoate (7 ppm) the reaction will occur only if tin is present at all test temperatures. The pH of biodiesel obtained was 6, similar to petrodiesel used commonly in diesel motors.