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Alfonso Lampen - One of the best experts on this subject based on the ideXlab platform.
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2 chloro 1 3 propanediol 2 mcpd and its Fatty Acid Esters cytotoxicity metabolism and transport by human intestinal caco 2 cells
Archives of Toxicology, 2015Co-Authors: Thorsten Buhrke, Falko Frenzel, Jan Kuhlmann, Alfonso LampenAbstract:The food contaminants 3-chloro-1,2-propanediol (3-MCPD) and 3-MCPD Fatty Acid Esters have attracted considerable attention in the past few years due to their toxic properties and their occurrence in numerous foods. Recently, significant amounts of the isomeric compounds 2-chloro-1,3-propanediol (2-MCPD) Fatty Acid Esters have been detected in refined oils. Beside the interrogation which toxic effects might be related to the core compound 2-MCPD, the key question from the risk assessment perspective is again—as it was discussed for 3-MCPD Fatty Acid Esters before—to which degree these Esters are hydrolyzed in the gut, thereby releasing free 2-MCPD. Here, we show that free 2-MCPD but not 2-MCPD Fatty Acid Esters were able to cross a monolayer of differentiated Caco-2 cells as an in vitro model for the human intestinal barrier. Instead, the Esters were hydrolyzed by the cells, thereby releasing free 2-MCPD which was neither absorbed nor metabolized by the cells. Cytotoxicity assays revealed that free 2-MCPD as well as free 3-MCPD was not toxic to Caco-2 cells up to a level of 1 mM, whereas cellular viability was slightly decreased in the presence of a few 2-MCPD and 3-MCPD Fatty Acid Esters at concentrations above 10 µM. The observed cytotoxic effects correlated well with the induction of caspase activity and might be attributed to the induction of apoptosis by free Fatty Acids which were released from the Esters in the presence of Caco-2 cells.
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relative oral bioavailability of 3 mcpd from 3 mcpd Fatty Acid Esters in rats
Archives of Toxicology, 2013Co-Authors: Klaus Abraham, Klaus E Appel, Edith Bergerpreiss, Elisabeth Apel, Susanne Gerling, Hans Mielke, Otto Creutzenberg, Alfonso LampenAbstract:In order to quantify the relative oral bioavailability of 3-chloropropane-1,2-diol (3-MCPD) from 3-MCPD Fatty Acid diEsters in vivo, 1,2-dipalmitoyl-3-chloropropane-1,2-diol (3-MCPD diester) and 3-MCPD were orally applied to rats in equimolar doses. In both cases, the time courses of 3-MCPD concentrations were measured in blood, various organs, tissues and intestinal luminal contents. The results show that 3-MCPD is released by enzymatic hydrolysis from the 3-MCPD diester in the gastrointestinal tract and distributed to blood, organs and tissues. Based on the measurements in blood, the areas under the curve (AUC) for 3-MCPD were calculated. By comparing both AUC, the relative amount of 3-MCPD bioavailable from the 3-MCPD diester was calculated to be 86 % on average of the amount bioavailable following administration of 3-MCPD. In view of limited experimental data, it is justified for the purpose of risk assessment to assume complete hydrolysis of the diEsters in the gastro-intestinal tract. Therefore, assessment of the extent of exposure to 3-MCPD released from its Fatty Acid Esters should be performed in the same way as exposure to the same molar quantity of 3-MCPD.
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toxicological assessment of 3 chloropropane 1 2 diol and glycidol Fatty Acid Esters in food
Molecular Nutrition & Food Research, 2011Co-Authors: Nadiya Bakhiya, Klaus E Appel, Klaus Abraham, Rainer Gurtler, Alfonso LampenAbstract:Fatty Acid Esters of 3-chloropropane-1,2-diol (3-MCPD) and glycidol are a newly identified class of food process contaminants. They are widespread in refined vegetable oils and fats and have been detected in vegetable fat-containing products, including infant formulas. There are no toxicological data available yet on the 3-MCPD and glycidol Esters, and the primary toxicological concern is based on the potential release of 3-MCPD or glycidol from the parent Esters by lipase-catalyzed hydrolysis in the gastrointestinal tract. Although 3-MCPD is assessed as a nongenotoxic carcinogen with a tolerable daily intake (TDI) of 2 μg/kg body weight (bw), glycidol is a known genotoxic carcinogen, which induces tumors in numerous organs of rodents. The initial exposure estimates, conducted by Federal Institute for Risk Assessment (BfR) under the assumption that 100% of the 3-MPCD and glycidol are released from their Esters, revealed especially that infants being fed commercial infant formula could ingest harmful amounts of 3-MCPD and glycidol. However, the real oral bioavailability may be lower. As this gives rise for toxicological concern, the currently available toxicological data of 3-MCPD and glycidol and their Esters are summarized in this review and discussed with regard to data gaps and further research needs.
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absorption and metabolism of the food contaminant 3 chloro 1 2 propanediol 3 mcpd and its Fatty Acid Esters by human intestinal caco 2 cells
Archives of Toxicology, 2011Co-Authors: Thorsten Buhrke, Rudiger Weisshaar, Alfonso LampenAbstract:3-Chloro-1,2-propanediol (3-MCPD) Fatty Acid Esters are formed upon thermal processing of fat-containing foods in the presence of chloride ions. Upon hydrolytic cleavage, these substances could release free 3-MCPD. This compound is toxicologically well characterised and displayed cancerogenic potential in rodent models. Recently, serious contaminations of different food products with 3-MCPD Fatty Acid Esters have been reported. In regard to a risk assessment, the key question is to which degree these 3-MCPD Fatty Acid Esters are hydrolysed in the human gut. Therefore, the aim of the present project was to examine the hydrolysis of 3-MCPD Fatty Acid Esters and the resulting release of free 3-MCPD by using differentiated Caco-2 cells, a cellular in vitro model for the human intestinal barrier. Here, we show that 3-MCPD Fatty Acid Esters at a concentration of 100 μM were neither absorbed by the cells nor the Esters were transported via a Caco-2 monolayer. 3-MCPD-1-monoEsters were hydrolysed in the presence of Caco-2 cells. In contrast, a 3-MCPD-1,2-diester used in this study was obviously absorbed and metabolised by the cells. Free 3-MCPD was not absorbed by the cells, but the substance migrated through a Caco-2 monolayer by paracellular diffusion. From these in vitro studies, we conclude that 3-MCPD-1-monoEsters are likely to be hydrolysed in the human intestine, thereby increasing the burden with free 3-MCPD. In contrast, intestinal cells seem to have the capacity to metabolise 3-MCPD diEsters, thereby detoxifying the 3-MCPD moiety.
Michio Takido - One of the best experts on this subject based on the ideXlab platform.
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constituents of compositae plants 2 triterpene diols triols and their 3 o Fatty Acid Esters from edible chrysanthemum flower extract and their anti inflammatory effects
Journal of Agricultural and Food Chemistry, 2001Co-Authors: Motohiko Ukiya, Yoshimasa Kasahara, Yumiko Kimura, Tamotsu Nikaido, Kazuo Koike, Toshihiro Akihisa, Ken Yasukawa, Michio TakidoAbstract:The n-hexane soluble and the nonsaponifiable lipid fractions of the edible flower extract of chrysanthemum (Chrysanthemum morifolium) were investigated for triterpene diol and triol constituents. These triterpenes occur as the 3-O-Fatty Acid Esters in the n-hexane soluble fraction from which 26 new and 6 known Fatty Acid Esters were isolated and characterized. From the nonsaponifiable lipid fraction, 24 triterpene diols and triols were isolated, of which 3 were new compounds: (24S)-25-methoxycycloartane-3β,24-diol (11), (24S)-25-methoxycycloartane-3β,24,28-triol (22), and 22α-methoxyfaradiol (23). Faradiol (9) and heliantriol C (19), present in the nonsaponifiable lipid fraction and as the 3-O-palmitoyl Esters in the n-hexane soluble fraction, were the most predominant triterpene diol and triol constituents. Fourteen triterpene diols and triols and 9 Fatty Acid Esters were evaluated with respect to their anti-inflammatory activity against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation in...
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constituents of compositae plants 2 triterpene diols triols and their 3 o Fatty Acid Esters from edible chrysanthemum flower extract and their anti inflammatory effects
Journal of Agricultural and Food Chemistry, 2001Co-Authors: Motohiko Ukiya, Yoshimasa Kasahara, Yumiko Kimura, Tamotsu Nikaido, Kazuo Koike, Toshihiro Akihisa, Ken Yasukawa, Michio TakidoAbstract:The n-hexane soluble and the nonsaponifiable lipid fractions of the edible flower extract of chrysanthemum (Chrysanthemum morifolium) were investigated for triterpene diol and triol constituents. These triterpenes occur as the 3-O-Fatty Acid Esters in the n-hexane soluble fraction from which 26 new and 6 known Fatty Acid Esters were isolated and characterized. From the nonsaponifiable lipid fraction, 24 triterpene diols and triols were isolated, of which 3 were new compounds: (24S)-25-methoxycycloartane-3beta,24-diol (11), (24S)-25-methoxycycloartane-3beta,24,28-triol (22), and 22alpha-methoxyfaradiol (23). Faradiol (9) and heliantriol C (19), present in the nonsaponifiable lipid fraction and as the 3-O-palmitoyl Esters in the n-hexane soluble fraction, were the most predominant triterpene diol and triol constituents. Fourteen triterpene diols and triols and 9 Fatty Acid Esters were evaluated with respect to their anti-inflammatory activity against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation in mice. All of the triterpenes examined showed marked inhibitory activity, with a 50% inhibitory dose (ID50) of 0.03-1.0 mg/ear, which was more inhibitive than quercetin (ID50 = 1.6 mg/ear), a known inhibitor of TPA-induced inflammation in mice.
Ahmet Alper Aydın - One of the best experts on this subject based on the ideXlab platform.
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high chain Fatty Acid Esters of 1 octadecanol as novel organic phase change materials and mathematical correlations for estimating the thermal properties of higher Fatty Acid Esters homologous series
Solar Energy Materials and Solar Cells, 2013Co-Authors: Ahmet Alper AydınAbstract:Abstract A series of high-chain Fatty Acid Esters of 1-octadecanol (stearyl alcohol) was synthesized with even carbon number Fatty Acids between C12 and C20 under vacuum and in the absence of catalyst. Ester syntheses were controlled via Fourier transform infrared (FT-IR) and thermo-physical analyses of the products. These Esters were particularly investigated in terms of their thermo-physical properties to be further used as Phase Change Materials (PCMs) in thermal energy storage. Purity, phase change temperature, enthalpy, specific heat (Cp), thermal decomposition and reliability after 1000 thermal cycles were presented with necessary statistical data. The DSC analyses indicated that the melting temperatures of the high-chain Fatty Acid Esters of stearyl alcohol were between 42 °C and 65 °C with phase change enthalpies above 200 kJ/kg. The results showed that these materials were favorable for low temperature heat transfer applications with their advantageous thermal properties and reliabilities. In addition to the presented novel PCMs, the influence of different higher alcohol and Fatty Acid combinations on thermal properties of the higher Esters' homologous series was also discussed in detail together with the outcomes of the other published researches. The developed empirical correlations provided accurate estimation of phase change temperature and enthalpy values of high-chain Fatty Acid Esters of higher alcohols without any instrumental analyses.
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High-chain Fatty Acid Esters of 1-hexadecanol for low temperature thermal energy storage with phase change materials
Solar Energy Materials and Solar Cells, 2012Co-Authors: Ahmet Alper Aydın, Adnan AydinAbstract:Abstract High-chain Fatty Acid Esters of higher alcohols have recently been investigated as novel organic phase change materials (PCM) for thermal energy storage. A series of high-chain Fatty Acid Esters of 1-hexadecanol (cetyl alcohol) were prepared through esterification reaction between 1-hexadecanol and C10–C20 Fatty Acids with even carbon number in the absence of catalyst and under vacuum. FT-IR spectrometer, differential scanning calorimeter (DSC) and thermo-gravimetric analyzer (TGA) were intensively used for chemical and thermal analyses. Phase change temperature, enthalpy, specific heat ( C p ), thermal decomposition and reliability after 1000 thermal cycles were obtained with necessary statistical data to clarify the thermal properties of the materials. The DSC analyses indicated that the melting temperatures of the high-chain Fatty Acid Esters of cetyl alcohol were between 29 o C and 60 o C with phase change enthalpy above 185 kJ/kg. The results showed that these materials were favorable for low temperature heat transfer applications with superior thermal properties and reliability.
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high chain Fatty Acid Esters of myristyl alcohol with even carbon number novel organic phase change materials for thermal energy storage 1
Solar Energy Materials and Solar Cells, 2011Co-Authors: Ahmet Alper Aydın, Hasancan OkutanAbstract:Abstract High-chain Fatty Acid Esters have not been investigated for their thermal properties as phase change materials (PCMs) in thermal energy storage. A series of high-chain Fatty Acid Esters of myristyl alcohol (1-tetradecanol) were synthesized via esterification of lauric, myristic, palmitic, stearic and arachidic Acids under vacuum and in the absence of any catalyst. The esterification reactions were studied by FT-IR spectroscopy. A differential scanning calorimeter (DSC) and a thermo-gravimetric analyzer (TGA) were intensively used to determine the thermal properties of the introduced thermal storage materials. The thermal properties were given in terms of phase change temperature, enthalpy, specific heat (Cp) and thermal decomposition temperature with related statistical data. The thermal reliability of the novel organic PCMs was investigated by thermal cycling with 1000 thermal cycles with respect to the thermal properties of the original synthesized PCMs. In addition to the synthesized Esters, one commercial product was also investigated. The DSC analyses indicated that the melting points of the novel organic PCMs were between 38 and 53 °C with phase change enthalpy above 200 kJ/kg. The effect of chemical structure of the materials on thermal properties was also discussed. The results showed that these materials were favorable for low temperature heat transfer applications with superior thermal properties and reliability.
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high chain Fatty Acid Esters of myristyl alcohol with odd carbon number novel organic phase change materials for thermal energy storage 2
Solar Energy Materials and Solar Cells, 2011Co-Authors: Ahmet Alper Aydın, Hasancan OkutanAbstract:Abstract High-chain Fatty Acid Esters have not been investigated for their thermal properties as phase change materials (PCMs) in thermal energy storage. A series of high-chain Fatty Acid Esters of myristyl alcohol (1-tetradecanol) were synthesized via esterification of lauric, myristic, palmitic, stearic and arachidic Acids under vacuum and in the absence of any catalyst. The esterification reactions were studied by FT-IR spectroscopy. A differential scanning calorimeter (DSC) and a thermo-gravimetric analyzer (TGA) were intensively used to determine the thermal properties of the introduced thermal storage materials. The thermal properties were given in terms of phase change temperature, enthalpy, specific heat (Cp) and thermal decomposition temperature with related statistical data. The thermal reliability of the novel organic PCMs was investigated by thermal cycling with 1000 thermal cycles with respect to the thermal properties of the original synthesized PCMs. In addition to the synthesized Esters, one commercial product was also investigated. The DSC analyses indicated that the melting points of the novel organic PCMs were between 38 and 53 °C with phase change enthalpy above 200 kJ/kg. The effect of chemical structure of the materials on thermal properties was also discussed. The results showed that these materials were favorable for low temperature heat transfer applications with superior thermal properties and reliability.
Barbara B Kahn - One of the best experts on this subject based on the ideXlab platform.
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faster protocol for endogenous Fatty Acid Esters of hydroxy Fatty Acid fahfa measurements
Analytical Chemistry, 2018Co-Authors: Matthew J Kolar, Barbara B Kahn, Meric Erikci Ertunc, Andrew T Nelson, Tina Chang, Mitchell P Christy, Lena Ohlsson, Magnus Harrod, Dionicio Siegel, Alan SaghatelianAbstract:Fatty Acid Esters of hydroxy Fatty Acids (FAHFAs) are a recently discovered class of endogenous lipids with antidiabetic and anti-inflammatory activities. Interest in these lipids is due to their unique biological activites and the observation that insulin-resistant people have lower palmitic Acid Esters of hydroxystearic Acid (PAHSA) levels, suggesting that a FAHFA deficiency may contribute to metabolic disease. Rigorous testing of this hypothesis will require the measurement of many clinical samples; however, current analytical workflows are too slow to enable samples to be analyzed quickly. Here we describe the development of a significantly faster workflow to measure FAHFAs that optimizes the fractionation and chromatography of these lipids. We can measure FAHFAs in 30 min with this new protocol versus 90 min using the older protocol with comparable performance in regioisomer detection and quantitation. We also discovered through this optimization that oleic Acid Esters of hydroxystearic Acids (OAHSAs), another family of FAHFAs, have a much lower background signal than PAHSAs, which makes them easier to measure. Our faster workflow was able to quantify changes in PAHSAs and OAHSAs in mouse tissues and human plasma, highlighting the potential of this protocol for basic and clinical applications.
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branched Fatty Acid Esters of hydroxy Fatty Acids are preferred substrates of the mody8 protein carboxyl ester lipase
Biochemistry, 2016Co-Authors: Matthew J Kolar, Ismail Syed, Edwin A Homan, William H Parsons, Tim Maher, Odile D Peroni, Karianne Fjeld, Anders Molven, Siddhesh S Kamat, Barbara B KahnAbstract:A recently discovered class of endogenous mammalian lipids, branched Fatty Acid Esters of hydroxy Fatty Acids (FAHFAs), possesses anti-diabetic and anti-inflammatory activities. Here, we identified and validated carboxyl ester lipase (CEL), a pancreatic enzyme hydrolyzing cholesteryl Esters and other dietary lipids, as a FAHFA hydrolase. Variants of CEL have been linked to maturity-onset diabetes of the young, type 8 (MODY8), and to chronic pancreatitis. We tested the FAHFA hydrolysis activity of the CEL MODY8 variant and found a modest increase in activity as compared with that of the normal enzyme. Together, the data suggest that CEL might break down dietary FAHFAs.
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a lc ms based workflow for measurement of branched Fatty Acid Esters of hydroxy Fatty Acids
Nature Protocols, 2016Co-Authors: Tejia Zhang, Ismail Syed, Matthew J Kolar, Edwin A Homan, Ulf Smith, Marcus Stahlman, Shili Chen, Barbara B Kahn, Jan Boren, Alan SaghatelianAbstract:Branched Fatty Acid Esters of hydroxy Fatty Acids (FAHFAs) are a recently discovered class of biological lipids. This protocol describes their extraction from serum and tissue samples, followed by enrichment and analysis by LC-MS.
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a lc ms based workflow for measurement of branched Fatty Acid Esters of hydroxy Fatty Acids
Nature Protocols, 2016Co-Authors: Tejia Zhang, Ismail Syed, Matthew J Kolar, Edwin A Homan, Ulf Smith, Marcus Stahlman, Shili Chen, Jan Boren, Qian Chu, Barbara B KahnAbstract:Branched Fatty Acid Esters of hydroxy Fatty Acids (FAHFAs) are a recently discovered class of endogenous mammalian lipids with antidiabetic and anti-inflammatory effects. We previously identified 16 different FAHFA families, such as branched palmitic Acid Esters of hydroxy stearic Acids (PAHSAs); each family consists of multiple isomers in which the branched ester is at different positions (e.g., 5- and 9-PAHSA). We anticipate increased need for PAHSA measurements as markers of metabolic and inflammatory health. In this protocol, we provide a detailed description of the extraction of FAHFAs from human or mouse tissues, their enrichment by solid-phase extraction and subsequent analysis by LC-MS. For a sample size of 6-12, the time frame is 2-3 d.
Thorsten Buhrke - One of the best experts on this subject based on the ideXlab platform.
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2 chloro 1 3 propanediol 2 mcpd and its Fatty Acid Esters cytotoxicity metabolism and transport by human intestinal caco 2 cells
Archives of Toxicology, 2015Co-Authors: Thorsten Buhrke, Falko Frenzel, Jan Kuhlmann, Alfonso LampenAbstract:The food contaminants 3-chloro-1,2-propanediol (3-MCPD) and 3-MCPD Fatty Acid Esters have attracted considerable attention in the past few years due to their toxic properties and their occurrence in numerous foods. Recently, significant amounts of the isomeric compounds 2-chloro-1,3-propanediol (2-MCPD) Fatty Acid Esters have been detected in refined oils. Beside the interrogation which toxic effects might be related to the core compound 2-MCPD, the key question from the risk assessment perspective is again—as it was discussed for 3-MCPD Fatty Acid Esters before—to which degree these Esters are hydrolyzed in the gut, thereby releasing free 2-MCPD. Here, we show that free 2-MCPD but not 2-MCPD Fatty Acid Esters were able to cross a monolayer of differentiated Caco-2 cells as an in vitro model for the human intestinal barrier. Instead, the Esters were hydrolyzed by the cells, thereby releasing free 2-MCPD which was neither absorbed nor metabolized by the cells. Cytotoxicity assays revealed that free 2-MCPD as well as free 3-MCPD was not toxic to Caco-2 cells up to a level of 1 mM, whereas cellular viability was slightly decreased in the presence of a few 2-MCPD and 3-MCPD Fatty Acid Esters at concentrations above 10 µM. The observed cytotoxic effects correlated well with the induction of caspase activity and might be attributed to the induction of apoptosis by free Fatty Acids which were released from the Esters in the presence of Caco-2 cells.
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absorption and metabolism of the food contaminant 3 chloro 1 2 propanediol 3 mcpd and its Fatty Acid Esters by human intestinal caco 2 cells
Archives of Toxicology, 2011Co-Authors: Thorsten Buhrke, Rudiger Weisshaar, Alfonso LampenAbstract:3-Chloro-1,2-propanediol (3-MCPD) Fatty Acid Esters are formed upon thermal processing of fat-containing foods in the presence of chloride ions. Upon hydrolytic cleavage, these substances could release free 3-MCPD. This compound is toxicologically well characterised and displayed cancerogenic potential in rodent models. Recently, serious contaminations of different food products with 3-MCPD Fatty Acid Esters have been reported. In regard to a risk assessment, the key question is to which degree these 3-MCPD Fatty Acid Esters are hydrolysed in the human gut. Therefore, the aim of the present project was to examine the hydrolysis of 3-MCPD Fatty Acid Esters and the resulting release of free 3-MCPD by using differentiated Caco-2 cells, a cellular in vitro model for the human intestinal barrier. Here, we show that 3-MCPD Fatty Acid Esters at a concentration of 100 μM were neither absorbed by the cells nor the Esters were transported via a Caco-2 monolayer. 3-MCPD-1-monoEsters were hydrolysed in the presence of Caco-2 cells. In contrast, a 3-MCPD-1,2-diester used in this study was obviously absorbed and metabolised by the cells. Free 3-MCPD was not absorbed by the cells, but the substance migrated through a Caco-2 monolayer by paracellular diffusion. From these in vitro studies, we conclude that 3-MCPD-1-monoEsters are likely to be hydrolysed in the human intestine, thereby increasing the burden with free 3-MCPD. In contrast, intestinal cells seem to have the capacity to metabolise 3-MCPD diEsters, thereby detoxifying the 3-MCPD moiety.
