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Michael Rychlik - One of the best experts on this subject based on the ideXlab platform.
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Challenges to Quantify Total Vitamin Activity: How to Combine the Contribution of Diverse Vitamers?
Current developments in nutrition, 2019Co-Authors: Jette Jakobsen, Alida Melse-boonstra, Michael RychlikAbstract:This state-of-the-art review aims to highlight the challenges in quantifying vitamin activity in foods that contain several Vitamers of a group, using as examples the fat-soluble vitamins A and D as well as the water-soluble folate. The absorption, metabolism, and physiology of these examples are described along with the current analytical methodology, with an emphasis on approaches to standardization. Moreover, the major food sources for the vitamins are numerated. The article focuses particularly on outlining the so-called SLAMENGHI factors influencing a vitamer's' ability to act as a vitamin, that is, molecular species, linkage, amount, matrix, effectors of absorption, nutrition status, genetics, host-related factors, and the interaction of these. After summarizing the current approaches to estimating the total content of each vitamin group, the review concludes by outlining the research gaps and future perspectives in vitamin analysis. There are no standardized methods for the quantification of the Vitamers of vitamin A, vitamin D, and folate in foods. For folate and β-carotene, a difference in vitamer activity between foods and supplements has been confirmed, whereas no difference has been observed for vitamin D. For differences in vitamer activity between provitamin A carotenoids and retinol, and between 25-hydroxyvitamin D and vitamin D, international consensus is lacking. The challenges facing each of the specific vitamin communities are the gaps in knowledge about bioaccessibility and bioavailability for each of the various Vitamers. The differences between the vitamins make it difficult to formulate a common strategy for assessing the quantitative differences between the Vitamers. In the future, optimized stationary digestive models and the more advanced dynamic digestive models combined with in vitro models for bioavailability could more closely resemble in vivo results. New knowledge will enable us to transfer nutrient recommendations into improved dietary advice to increase public health throughout the human life cycle.
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improved stable isotope dilution assay for dietary folates using lc ms ms and its application to strawberries
Frontiers in chemistry, 2018Co-Authors: Lisa Striegel, Soraya Chebib, Michael Netzel, Michael RychlikAbstract:Folates play an important role in the human body and a deficiency of this vitamin can cause several diseases. Therefore, a reliable analytical method is crucial for the determination of folate Vitamers in strawberries and other dietary folate sources. A stable isotope dilution LC-MS/MS method for analyzing folates in food was developed and validated. The folate Vitamers Pteroylmonoglutamic acid, tetrahydrofolate, 5-methyltetrahydrofolate, and 5-formyltetrahydrofolate were quantified using C-13-labeled internal standards. Validation of the assay was accomplished by determining linearity, precision, recovery, limit of detection, and limit of quantification and revealed to be a precise, sensitive, and accurate method to determine folate Vitamers. Strawberries are worldwide consumed and known to be a good dietary source of nutritive compounds. Using this method, folate concentrations in selected commercial strawberry cultivars and experimental breeding lines grown in Germany and Australia were investigated. Total folates varied from 59 to 153 mu g/100 g on fresh weight basis. Furthermore, folate content after lyophilizing or freezing did not show any significant differences compared to fresh strawberries. However, significant losses of total folates in pureed strawberries could be observed after 5 days of storage with only 16% of the original concentration retained. In summary, some of the investigated strawberry cultivars/breeding lines can be considered as rich dietary sources of natural folates.
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a rapid method for sensitive profiling of folates from plant leaf by ultra performance liquid chromatography coupled to tandem quadrupole mass spectrometer
Journal of Chromatography B, 2017Co-Authors: Michael Rychlik, M J I Shohag, Qianying Yang, Jie Zhang, Farhana Zerin Khan, Zhenli He, Xiaoe YangAbstract:Abstract Previous published methods for the analysis of folates are time consuming because of lengthy sample extraction, clean-up and total running time. This study details the development and validation of a rapid, sensitive and robust method that combines a simple extraction step with ultra-performance liquid chromatography coupled to tandem quadrupole mass spectrometry. Here, we reported application of a tandem quadrupole mass spectrometer to analyze maximum seven Vitamers of folate from plant origin. The analytical performance was evaluated by linearity, sensitivity, precision, recovery test and analysis of certified reference materials. The limit of detection and limit of quantification ranged between 0.003 and 0.021 μg/100 g FW and between 0.011 and 0.041 μg/100 g FW, respectively; the recovery and precession ranged from 71.27 to 99. 01% and from 1.7 to 7.8% RSD, respectively, depending upon folate Vitamers. This newly developed and validated method is rapid (a chromatographic run time of 5 min), easy to be performed (no laborious and time consuming clean-up) and can be used to simultaneously analyze seven Vitamers of folate from plant sources.
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folates in fruits and vegetables contents processing and stability
Comprehensive Reviews in Food Science and Food Safety, 2016Co-Authors: Nicolas Delchier, Anna-lena Herbig, Michael Rychlik, Catherine M.g.c. RenardAbstract:Folates play a key role in human one-carbon metabolism and are provided by food. It is well established that folates are beneficial in the prevention of neural tube defects and cardiovascular and neurodegenerative diseases. Fruits and vegetables, and especially green vegetables, are the main sources of folates. In parallel, fruits and vegetables, with high contents of folates, are mostly consumed after processing, such as, canning, freezing, or home-cooking, which involve folate losses during their preparation. Hence, it is important to know the percentage of folate losses during processing and, moreover, the mechanisms underlying those losses. The current knowledge on folate losses from fruit and vegetables are presented in this review. They depend on the nature of the respective fruit or vegetable and the respective treatment. For example, steaming involves almost no folate losses in contrast to boiling. Two main mechanisms are involved in folate losses: (i) leaching into the surrounding liquid and (ii) oxidation during heat treatment, the latter of which depending on the nature of the vitamer considered. In this respect, a vitamer stability decreases in the order starting from folic acid followed by 5-HCO-H4folate, 5-CH3-H4folate, and, finally, H4folate. Further studies are required, especially on the diffusion of the Vitamers in real foods and on the determination of folate degradation products.
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Determination of kinetic constants and degradation products of formyl folates derivatives, during heat treatments and oxygen exposure.
2016Co-Authors: Nicolas Delchier, Anna-lena Herbig, Catherine Renard, Michael RychlikAbstract:Folate is a vitamin group consisting of water-soluble Vitamers, which differ by the nature of the substitution (N5 or N10), the oxidation degree and the length of the glutamate tail. A sufficient supply is effective in reducing neural tube defects, cardiovascular and neurodegenerative diseases. Green vegetables are a major source of folates in European diets. They are most often consumed after processing (industrial or cooking), which can lead to folate losses due to heat degradation and oxidation. The main folate vitamer studied in model solution or during industrial processing still is 5-methyltetrahyrofolate. Therefore, we aimed to determine the kinetics parameter and the degradation products for two other Vitamers abundant in green vegetables, namely 5-formyltetrahydrofolate (5-HCO-H4folate) and 10-formylfolic acid (10-HCO-PteGlu), during heat treatment and in the presence of an oxidation catalyst. Kinetics were carried out in ammonium buffer pH 5 and 7 and in water at room temperature, 85°C and 100°C. Kinetics were also carried out in the presence of hydrogen peroxide. Samples were collected for 4 hours and analysed by LC-MS and FT-ICR. Kinetics were modelled, degradation rate constant (k) and activation Energy (Ea) were determined according to the first order equation. As compared with 5-HCO-H4folate, 10-HCO-PteGlu remained quite stable over 4 hours with a maximum of loss of circa 50% in maximum. 5-HCO-H4folate was highly degraded during the kinetics. The main factors involved in losses during the kinetics were the temperature and the concentration of hydrogen peroxide. Degradation and transition products of 5-HCO-H4folate were identified by LC-MS as 10-HCO-PteGlu, methenyltetrahydrofolate, and para-aminobenzoyl glutamic acid. Further compounds were detected by LC-MS and tentatively identified by FT-ICR. Our study enabled to identify the degradation kinetics constant and degradation compounds of formyl folates, which is relevant for understanding folate degradation mechanisms during vegetables processing.
M J I Shohag - One of the best experts on this subject based on the ideXlab platform.
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a rapid method for sensitive profiling of folates from plant leaf by ultra performance liquid chromatography coupled to tandem quadrupole mass spectrometer
Journal of Chromatography B, 2017Co-Authors: Michael Rychlik, M J I Shohag, Qianying Yang, Jie Zhang, Farhana Zerin Khan, Zhenli He, Xiaoe YangAbstract:Abstract Previous published methods for the analysis of folates are time consuming because of lengthy sample extraction, clean-up and total running time. This study details the development and validation of a rapid, sensitive and robust method that combines a simple extraction step with ultra-performance liquid chromatography coupled to tandem quadrupole mass spectrometry. Here, we reported application of a tandem quadrupole mass spectrometer to analyze maximum seven Vitamers of folate from plant origin. The analytical performance was evaluated by linearity, sensitivity, precision, recovery test and analysis of certified reference materials. The limit of detection and limit of quantification ranged between 0.003 and 0.021 μg/100 g FW and between 0.011 and 0.041 μg/100 g FW, respectively; the recovery and precession ranged from 71.27 to 99. 01% and from 1.7 to 7.8% RSD, respectively, depending upon folate Vitamers. This newly developed and validated method is rapid (a chromatographic run time of 5 min), easy to be performed (no laborious and time consuming clean-up) and can be used to simultaneously analyze seven Vitamers of folate from plant sources.
Xiaoe Yang - One of the best experts on this subject based on the ideXlab platform.
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a rapid method for sensitive profiling of folates from plant leaf by ultra performance liquid chromatography coupled to tandem quadrupole mass spectrometer
Journal of Chromatography B, 2017Co-Authors: Michael Rychlik, M J I Shohag, Qianying Yang, Jie Zhang, Farhana Zerin Khan, Zhenli He, Xiaoe YangAbstract:Abstract Previous published methods for the analysis of folates are time consuming because of lengthy sample extraction, clean-up and total running time. This study details the development and validation of a rapid, sensitive and robust method that combines a simple extraction step with ultra-performance liquid chromatography coupled to tandem quadrupole mass spectrometry. Here, we reported application of a tandem quadrupole mass spectrometer to analyze maximum seven Vitamers of folate from plant origin. The analytical performance was evaluated by linearity, sensitivity, precision, recovery test and analysis of certified reference materials. The limit of detection and limit of quantification ranged between 0.003 and 0.021 μg/100 g FW and between 0.011 and 0.041 μg/100 g FW, respectively; the recovery and precession ranged from 71.27 to 99. 01% and from 1.7 to 7.8% RSD, respectively, depending upon folate Vitamers. This newly developed and validated method is rapid (a chromatographic run time of 5 min), easy to be performed (no laborious and time consuming clean-up) and can be used to simultaneously analyze seven Vitamers of folate from plant sources.
Nicolas Delchier - One of the best experts on this subject based on the ideXlab platform.
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folates in fruits and vegetables contents processing and stability
Comprehensive Reviews in Food Science and Food Safety, 2016Co-Authors: Nicolas Delchier, Anna-lena Herbig, Michael Rychlik, Catherine M.g.c. RenardAbstract:Folates play a key role in human one-carbon metabolism and are provided by food. It is well established that folates are beneficial in the prevention of neural tube defects and cardiovascular and neurodegenerative diseases. Fruits and vegetables, and especially green vegetables, are the main sources of folates. In parallel, fruits and vegetables, with high contents of folates, are mostly consumed after processing, such as, canning, freezing, or home-cooking, which involve folate losses during their preparation. Hence, it is important to know the percentage of folate losses during processing and, moreover, the mechanisms underlying those losses. The current knowledge on folate losses from fruit and vegetables are presented in this review. They depend on the nature of the respective fruit or vegetable and the respective treatment. For example, steaming involves almost no folate losses in contrast to boiling. Two main mechanisms are involved in folate losses: (i) leaching into the surrounding liquid and (ii) oxidation during heat treatment, the latter of which depending on the nature of the vitamer considered. In this respect, a vitamer stability decreases in the order starting from folic acid followed by 5-HCO-H4folate, 5-CH3-H4folate, and, finally, H4folate. Further studies are required, especially on the diffusion of the Vitamers in real foods and on the determination of folate degradation products.
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Determination of kinetic constants and degradation products of formyl folates derivatives, during heat treatments and oxygen exposure.
2016Co-Authors: Nicolas Delchier, Anna-lena Herbig, Catherine Renard, Michael RychlikAbstract:Folate is a vitamin group consisting of water-soluble Vitamers, which differ by the nature of the substitution (N5 or N10), the oxidation degree and the length of the glutamate tail. A sufficient supply is effective in reducing neural tube defects, cardiovascular and neurodegenerative diseases. Green vegetables are a major source of folates in European diets. They are most often consumed after processing (industrial or cooking), which can lead to folate losses due to heat degradation and oxidation. The main folate vitamer studied in model solution or during industrial processing still is 5-methyltetrahyrofolate. Therefore, we aimed to determine the kinetics parameter and the degradation products for two other Vitamers abundant in green vegetables, namely 5-formyltetrahydrofolate (5-HCO-H4folate) and 10-formylfolic acid (10-HCO-PteGlu), during heat treatment and in the presence of an oxidation catalyst. Kinetics were carried out in ammonium buffer pH 5 and 7 and in water at room temperature, 85°C and 100°C. Kinetics were also carried out in the presence of hydrogen peroxide. Samples were collected for 4 hours and analysed by LC-MS and FT-ICR. Kinetics were modelled, degradation rate constant (k) and activation Energy (Ea) were determined according to the first order equation. As compared with 5-HCO-H4folate, 10-HCO-PteGlu remained quite stable over 4 hours with a maximum of loss of circa 50% in maximum. 5-HCO-H4folate was highly degraded during the kinetics. The main factors involved in losses during the kinetics were the temperature and the concentration of hydrogen peroxide. Degradation and transition products of 5-HCO-H4folate were identified by LC-MS as 10-HCO-PteGlu, methenyltetrahydrofolate, and para-aminobenzoyl glutamic acid. Further compounds were detected by LC-MS and tentatively identified by FT-ICR. Our study enabled to identify the degradation kinetics constant and degradation compounds of formyl folates, which is relevant for understanding folate degradation mechanisms during vegetables processing.
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Folates in fruit and vegetables: contents, processing and stability.
Comprehensive Reviews in Food Science and Food Safety, 2016Co-Authors: Catherine Renard, Nicolas Delchier, Anna-lena Herbig, Michael RychlikAbstract:Folates play a key role in human one-carbon metabolism and are provided by food. It is well established that folates are beneficial in the prevention of neural tube defects and cardiovascular and neurodegenerative diseases. Fruits and vegetables, and especially green vegetables, are the main sources of folates. In parallel, fruits and vegetables, with high contents of folates, are mostly consumed after processing, such as, canning, freezing, or home-cooking, which involve folate losses during their preparation. Hence, it is important to know the percentage of folate losses during processing and, moreover, the mechanisms underlying those losses. The current knowledge on folate losses from fruit and vegetables are presented in this review. They depend on the nature of the respective fruit or vegetable and the respective treatment. For example, steaming involves almost no folate losses in contrast to boiling. Two main mechanisms are involved in folate losses: (i) leaching into the surrounding liquid and (ii) oxidation during heat treatment, the latter of which depending on the nature of the vitamer considered. In this respect, a vitamer stability decreases in the order starting from folic acid followed by 5-HCO-H4folate, 5-CH3-H4folate, and, finally, H4folate. Further studies are required, especially on the diffusion of the Vitamers in real foods and on the determination of folate degradation products.
Anna-lena Herbig - One of the best experts on this subject based on the ideXlab platform.
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folates in fruits and vegetables contents processing and stability
Comprehensive Reviews in Food Science and Food Safety, 2016Co-Authors: Nicolas Delchier, Anna-lena Herbig, Michael Rychlik, Catherine M.g.c. RenardAbstract:Folates play a key role in human one-carbon metabolism and are provided by food. It is well established that folates are beneficial in the prevention of neural tube defects and cardiovascular and neurodegenerative diseases. Fruits and vegetables, and especially green vegetables, are the main sources of folates. In parallel, fruits and vegetables, with high contents of folates, are mostly consumed after processing, such as, canning, freezing, or home-cooking, which involve folate losses during their preparation. Hence, it is important to know the percentage of folate losses during processing and, moreover, the mechanisms underlying those losses. The current knowledge on folate losses from fruit and vegetables are presented in this review. They depend on the nature of the respective fruit or vegetable and the respective treatment. For example, steaming involves almost no folate losses in contrast to boiling. Two main mechanisms are involved in folate losses: (i) leaching into the surrounding liquid and (ii) oxidation during heat treatment, the latter of which depending on the nature of the vitamer considered. In this respect, a vitamer stability decreases in the order starting from folic acid followed by 5-HCO-H4folate, 5-CH3-H4folate, and, finally, H4folate. Further studies are required, especially on the diffusion of the Vitamers in real foods and on the determination of folate degradation products.
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Determination of kinetic constants and degradation products of formyl folates derivatives, during heat treatments and oxygen exposure.
2016Co-Authors: Nicolas Delchier, Anna-lena Herbig, Catherine Renard, Michael RychlikAbstract:Folate is a vitamin group consisting of water-soluble Vitamers, which differ by the nature of the substitution (N5 or N10), the oxidation degree and the length of the glutamate tail. A sufficient supply is effective in reducing neural tube defects, cardiovascular and neurodegenerative diseases. Green vegetables are a major source of folates in European diets. They are most often consumed after processing (industrial or cooking), which can lead to folate losses due to heat degradation and oxidation. The main folate vitamer studied in model solution or during industrial processing still is 5-methyltetrahyrofolate. Therefore, we aimed to determine the kinetics parameter and the degradation products for two other Vitamers abundant in green vegetables, namely 5-formyltetrahydrofolate (5-HCO-H4folate) and 10-formylfolic acid (10-HCO-PteGlu), during heat treatment and in the presence of an oxidation catalyst. Kinetics were carried out in ammonium buffer pH 5 and 7 and in water at room temperature, 85°C and 100°C. Kinetics were also carried out in the presence of hydrogen peroxide. Samples were collected for 4 hours and analysed by LC-MS and FT-ICR. Kinetics were modelled, degradation rate constant (k) and activation Energy (Ea) were determined according to the first order equation. As compared with 5-HCO-H4folate, 10-HCO-PteGlu remained quite stable over 4 hours with a maximum of loss of circa 50% in maximum. 5-HCO-H4folate was highly degraded during the kinetics. The main factors involved in losses during the kinetics were the temperature and the concentration of hydrogen peroxide. Degradation and transition products of 5-HCO-H4folate were identified by LC-MS as 10-HCO-PteGlu, methenyltetrahydrofolate, and para-aminobenzoyl glutamic acid. Further compounds were detected by LC-MS and tentatively identified by FT-ICR. Our study enabled to identify the degradation kinetics constant and degradation compounds of formyl folates, which is relevant for understanding folate degradation mechanisms during vegetables processing.
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Folates in fruit and vegetables: contents, processing and stability.
Comprehensive Reviews in Food Science and Food Safety, 2016Co-Authors: Catherine Renard, Nicolas Delchier, Anna-lena Herbig, Michael RychlikAbstract:Folates play a key role in human one-carbon metabolism and are provided by food. It is well established that folates are beneficial in the prevention of neural tube defects and cardiovascular and neurodegenerative diseases. Fruits and vegetables, and especially green vegetables, are the main sources of folates. In parallel, fruits and vegetables, with high contents of folates, are mostly consumed after processing, such as, canning, freezing, or home-cooking, which involve folate losses during their preparation. Hence, it is important to know the percentage of folate losses during processing and, moreover, the mechanisms underlying those losses. The current knowledge on folate losses from fruit and vegetables are presented in this review. They depend on the nature of the respective fruit or vegetable and the respective treatment. For example, steaming involves almost no folate losses in contrast to boiling. Two main mechanisms are involved in folate losses: (i) leaching into the surrounding liquid and (ii) oxidation during heat treatment, the latter of which depending on the nature of the vitamer considered. In this respect, a vitamer stability decreases in the order starting from folic acid followed by 5-HCO-H4folate, 5-CH3-H4folate, and, finally, H4folate. Further studies are required, especially on the diffusion of the Vitamers in real foods and on the determination of folate degradation products.
