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Ying Dong - One of the best experts on this subject based on the ideXlab platform.
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D-isoascorbyl palmitate: lipase-catalyzed synthesis, structural characterization and process optimization using response surface methodology.
Chemistry Central journal, 2013Co-Authors: Wenjing Sun, Hong-xia Zhao, Fengjie Cui, Qiang Zhou, Jingya Qian, Ying DongAbstract:Isoascorbic Acid is a stereoisomer of L-ascorbic Acid, and widely used as a food antioxidant. However, its highly hydrophilic behavior prevents its application in cosmetics or fats and oils-based foods. To overcome this problem, D-isoascorbyl palmitate was synthesized in the present study for improving the Isoascorbic Acid’s oil solubility with an immobilized lipase in organic media. The structural information of synthesized product was clarified using LC-ESI-MS, FT-IR, 1H and 13C NMR analysis, and process parameters for high yield of D-isoascorbyl palmitate were optimized by using One–factor-at-a-time experiments and response surface methodology (RSM). The synthesized product had the purity of 95% and its structural characteristics were confirmed as isoascorbyl palmitate by LC-ESI-MS, FT-IR, 1H, and 13C NMR analysis. Results from “one–factor-at-a-time” experiments indicated that the enzyme load, reaction temperature and D-Isoascorbic-to-palmitic Acid molar ratio had a significant effect on the D-isoascorbyl palmitate conversion rate. 95.32% of conversion rate was obtained by using response surface methodology (RSM) under the the optimized condition: enzyme load of 20% (w/w), reaction temperature of 53°C and D- Isoascorbic-to-palmitic Acid molar ratio of 1:4 when the reaction parameters were set as: acetone 20 mL, 40 g/L of molecular sieves content, 200 rpm speed for 24-h reaction time. The findings of this study can become a reference for developing industrial processes for the preparation of Isoascorbic Acid ester, which might be used in food additives, cosmetic formulations and for the synthesis of other Isoascorbic Acid derivatives.
Wenjing Sun - One of the best experts on this subject based on the ideXlab platform.
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D-isoascorbyl palmitate: lipase-catalyzed synthesis, structural characterization and process optimization using response surface methodology.
Chemistry Central journal, 2013Co-Authors: Wenjing Sun, Hong-xia Zhao, Fengjie Cui, Qiang Zhou, Jingya Qian, Ying DongAbstract:Isoascorbic Acid is a stereoisomer of L-ascorbic Acid, and widely used as a food antioxidant. However, its highly hydrophilic behavior prevents its application in cosmetics or fats and oils-based foods. To overcome this problem, D-isoascorbyl palmitate was synthesized in the present study for improving the Isoascorbic Acid’s oil solubility with an immobilized lipase in organic media. The structural information of synthesized product was clarified using LC-ESI-MS, FT-IR, 1H and 13C NMR analysis, and process parameters for high yield of D-isoascorbyl palmitate were optimized by using One–factor-at-a-time experiments and response surface methodology (RSM). The synthesized product had the purity of 95% and its structural characteristics were confirmed as isoascorbyl palmitate by LC-ESI-MS, FT-IR, 1H, and 13C NMR analysis. Results from “one–factor-at-a-time” experiments indicated that the enzyme load, reaction temperature and D-Isoascorbic-to-palmitic Acid molar ratio had a significant effect on the D-isoascorbyl palmitate conversion rate. 95.32% of conversion rate was obtained by using response surface methodology (RSM) under the the optimized condition: enzyme load of 20% (w/w), reaction temperature of 53°C and D- Isoascorbic-to-palmitic Acid molar ratio of 1:4 when the reaction parameters were set as: acetone 20 mL, 40 g/L of molecular sieves content, 200 rpm speed for 24-h reaction time. The findings of this study can become a reference for developing industrial processes for the preparation of Isoascorbic Acid ester, which might be used in food additives, cosmetic formulations and for the synthesis of other Isoascorbic Acid derivatives.
Rene Madere - One of the best experts on this subject based on the ideXlab platform.
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Electrochemical Determination of Ascorbic Acid and Isoascorbic Acid in Ground Meat and in Processed Foods by High Pressure Liquid Chromatography
Journal of Food Composition and Analysis, 1998Co-Authors: Nick Hidiroglou, Rene Madere, Willy BehrensAbstract:Abstract Some researchers have reported that ascorbic Acid (AA) and/or Isoascorbic Acid (IAA) was detected in ground meat, prompting our laboratory to undertake a small survey to determine if the addition of AA and IAA to ground meats was common practice. The study was expanded to include dairy products, luncheon meats, meal replacements, diet products, vegetable and fruit drinks, and beverages. Detection of AA, dehydroascorbic Acid (DHAA), IAA, and dehydroIsoascorbic Acid (DHIAA) was done by HPLC with electrochemical detection. Two PLRP-S columns cooled to 5°C were used with a 20 mM sodium phosphate monobasic, monohydrate (NaH 2 PO 4 -H 2 O) and 0.17% (v/v) metaphosphoric Acid (HPO 3 ) mobile phase, pH 2.2. The limit of detection was 0.2 mg/100 g sample. Generally, variable amounts of AA and DHAA were detected, although in some foods, traces or no vitamin C was detected while only processed meats and ice tea contained IAA.
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Influence of oral dosing with D-Isoascorbic Acid on L-ascorbic Acid content in guinea pig tissues
The Journal of Nutritional Biochemistry, 1997Co-Authors: Nick Hidiroglou, Rene Madere, Mary R. L'abbéAbstract:Abstract The effect of graded doses of D-Isoascorbic Acid (IAA) on the tissue content of ascorbic Acid (AA) in guinea pigs administered a marginal intake of ascorbic Acid was studied. Thirty guinea pigs (inbred Hartley-strain) were randomly assigned to three equally sized treatment groups: 1) 1 mg AA (only); 2) 1 mg AA + 20 mg IAA, or 3) 1 mg AA + 100 mg IAA. Ascorbic Acid alone or in combination with IAA was orally administered daily to all animals over 42 consecutive days, after which time the animals were sacrificed. Over the study period, animals dosed with 1 mg AA plus 100 mg IAA had a higher rate of weight gain than those dosed with 1 mg AA or 1 mg AA + 20 mg IAA. Tissue concentrations of AA, IAA, and their oxidized forms, dehydroascorbic Acid (DHAA) and dehydroIsoascorbic Acid (DHIAA) were determined by high-pressure liquid chromatography equipped with an electrochemical detector. In guinea pigs dosed with either 20 or 100 mg IAA, AA levels in the plasma, brain, liver, adrenals, lungs, kidneys, spleen, and heart were significantly decreased (P
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Ascorbic Acid, Isoascorbic Acid, Dehydroascorbic Acid, and DehydroIsoascorbic Acid in Selected Food Products
Journal of Food Composition and Analysis, 1994Co-Authors: Willy Behrens, Rene MadereAbstract:Abstract A sensitive high-performance liquid chromatography method with electrochemical detection was used to estimate ascorbic, dehydroascorbic, Isoascorbic, and dehydroIsoascorbic Acid in applesauce, fruit juices, canned fruits, peach marmalade, and beginner and junior baby foods. The selected processed foods showed variable amounts of total vitamin C, which in almost all the cases was in the form of ascorbic Acid; dehydroascorbic Acid was found in small proportion. Isoascorbic Acid and its oxidized form, dehydroIsoascorbic Acid, was present in small amounts in some samples of applesauce and in peaches and pears of beginner and junior baby food.
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A Procedure for the Separation and Quantitative Analysis of Ascorbic Acid, Dehydroascorbic Acid, Isoascorbic Acid, and DehydroIsoascorbic Acid in Food and Animal Tissue
Journal of Liquid Chromatography, 1994Co-Authors: Willy A. Behrens, Rene MadereAbstract:Abstract A procedure is presented for the direct and simultaneous determination of ascorbic Acid (AA) and Isoascorbic Acid (IAA) in food products and animal tissues by reverse phase high-performance liquid chromatography. Two PLRP-S columns in series were used with a pH 2.2 mobile phase containing 20 mM phosphate buffer and 0.17% metaphosphoric Acid. An amperometric detector set at 0.7 volt and 20 mA was used. As little as 0.5 ng of each compound could be detected. When the same samples were incubated with homocysteine to reduce dehydroascorbic Acid (DHAA) and dehydroIsoascorbic Acid (DHIAA) to AA and IAA respectively and reinjected into the system, the values for total AA and IAA were obtained. The concentration of the oxidized forms, DHAA and DHIAA, could then be calculated by substraction.
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Quantitative Analysis of Ascorbic Acid and Isoascorbic Acid in Foods by High-Performance Liquid Chromatography with Electrochemical Detection
Journal of Liquid Chromatography, 1992Co-Authors: Willy A. Behrens, Rene MadereAbstract:Abstract A procedure is presented for the direct and simultaneous determination of ascorbic Acid (AA) and Isoascorbic Acid (IAA) in food products by paired-ion reverse-phase high-performance liquid chromatography. Three Supelcosil C18 columns were used with a pH 5.4 mobile phase containing 0.04 M sodium acetate, 5 mM tetrabutylammonium hydrogen sulfate and 0.015% metaphosphoric Acid. Food samples, preserved with metaphosphoric Acid and diluted with mobil phase, were injected (20μI) using an autosampler. Detection of AA and IAA was by amperometry using a glassy carbon electrode and Ag/AgCl reference electrode. The applied potential was +0.6 volt and the sensitivity was 20 nA. As little as 0.5 ng of each component could be detected under these conditions. When the same samples were incubated with homocysteine to reduce dehydroascorbic Acid (DHAA) and dehydroIsoascorbic Acid (DHIAA) to AA and IAA respectively and reinjected into the system the values for total AA and IAA were obtained. The concentration of t...
Xia Lin - One of the best experts on this subject based on the ideXlab platform.
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a novel solid state electrochemiluminescent enantioselective sensor for ascorbic Acid and Isoascorbic Acid
Electroanalysis, 2017Co-Authors: Shu Zhu, Xia Lin, Qinghong Wang, Qiao Xia, Peiyao RanAbstract:A novel, stable, solid-state and stereoselective electrochemiluminescence (ECL) sensor has been designed to enantioselectively discriminate ascorbic Acid (AA) and Isoascorbic Acid (IAA) by immobilizing Ru(bpy)32+ (Ru), thiolated β-cyclodextrin (β-CD-SH) and gold/platinum hybrid nanoparticles supported on multiwalled carbon nanotube/silica coaxial nanocables (GP-CSCN) on glassy carbon electrode. All chemical compounds could be immobilized on the surface of electrode stably through nafion film, and high stereoselectivity could be introduced to the sensor via the synergistic effects of the β-CD-SH and GP-CSCN nanomaterials. When the developed sensor interacted with AA and IAA, obvious difference of ECL intensities was observed, and a larger intensity was obtained from AA, which indicated that this strategy could be employed to enantioselectively recognize AA and IAA. As a result, ECL technique might act as a promising method for recognition of chiral compounds.
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A Novel Solid‐state Electrochemiluminescent Enantioselective Sensor for Ascorbic Acid and Isoascorbic Acid
Electroanalysis, 2016Co-Authors: Shu Zhu, Xia Lin, Qinghong Wang, Qiao Xia, Peiyao RanAbstract:A novel, stable, solid-state and stereoselective electrochemiluminescence (ECL) sensor has been designed to enantioselectively discriminate ascorbic Acid (AA) and Isoascorbic Acid (IAA) by immobilizing Ru(bpy)32+ (Ru), thiolated β-cyclodextrin (β-CD-SH) and gold/platinum hybrid nanoparticles supported on multiwalled carbon nanotube/silica coaxial nanocables (GP-CSCN) on glassy carbon electrode. All chemical compounds could be immobilized on the surface of electrode stably through nafion film, and high stereoselectivity could be introduced to the sensor via the synergistic effects of the β-CD-SH and GP-CSCN nanomaterials. When the developed sensor interacted with AA and IAA, obvious difference of ECL intensities was observed, and a larger intensity was obtained from AA, which indicated that this strategy could be employed to enantioselectively recognize AA and IAA. As a result, ECL technique might act as a promising method for recognition of chiral compounds.
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enantioselective recognition of ascorbic Acid and Isoascorbic Acid on hs β cyclodextrin gold nanoparticles hollow carbon microspheres hybrid modified electrodes
New Journal of Chemistry, 2016Co-Authors: Quanhong Ying, Qiao Xia, Ni Wang, Xia LinAbstract:The HS-β-cyclodextrin/gold nanoparticles/hollow carbon microspheres (HS-β-CD/AuNPs/HCMS) hybrids were successfully synthesized and characterized via scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). A simple and reliable chiral sensing platform constructed from the prepared hybrids was used for enantioselective recognition of ascorbic Acid (AA) and Isoascorbic Acid (IAA). Moreover, the stereoselectivity of HS-β-CD/AuNPs/HCMS to AA or IAA was investigated via differential pulse voltammetry (DPV). The results showed obvious differences in the peak currents of AA and IAA, demonstrating that this strategy could be employed to enantioselectively recognize AA and IAA. Under the optimum conditions, the chiral sensor exhibited an acceptable linear response to AA or IAA in the linear range of 1.0 × 10−4 to 5.0 × 10−3 M with a limit of detection of 1.7 × 10−5 M (S/N = 3). This approach provided a new available sensing interface to recognize and determine AA or IAA by electrochemical technology.
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Enantioselective recognition of ascorbic Acid and Isoascorbic Acid on HS-β-cyclodextrin/gold nanoparticles/hollow carbon microspheres hybrid modified electrodes
New Journal of Chemistry, 2016Co-Authors: Quanhong Ying, Qiao Xia, Ni Wang, Xia LinAbstract:The HS-β-cyclodextrin/gold nanoparticles/hollow carbon microspheres (HS-β-CD/AuNPs/HCMS) hybrids were successfully synthesized and characterized via scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). A simple and reliable chiral sensing platform constructed from the prepared hybrids was used for enantioselective recognition of ascorbic Acid (AA) and Isoascorbic Acid (IAA). Moreover, the stereoselectivity of HS-β-CD/AuNPs/HCMS to AA or IAA was investigated via differential pulse voltammetry (DPV). The results showed obvious differences in the peak currents of AA and IAA, demonstrating that this strategy could be employed to enantioselectively recognize AA and IAA. Under the optimum conditions, the chiral sensor exhibited an acceptable linear response to AA or IAA in the linear range of 1.0 × 10−4 to 5.0 × 10−3 M with a limit of detection of 1.7 × 10−5 M (S/N = 3). This approach provided a new available sensing interface to recognize and determine AA or IAA by electrochemical technology.
Jean-claude Depezay - One of the best experts on this subject based on the ideXlab platform.
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Enantiopure aminotriol from d-Isoascorbic Acid synthesis of d-threo-C-18-sphingosine
Tetrahedron: Asymmetry, 1996Co-Authors: Arounarith Tuch, Michèle Sanière, Yves Le Merrer, Jean-claude DepezayAbstract:Abstract Enantiopure suitably N , O -protected aminotriol has been prepared from d -Isoascorbic Acid. The utility of this homochiral building block in the synthesis of (2R,3R)- d -threo- C 18 -sphingosine is described via a Wittig reaction on a N , O -protected β-amino-α-hydroxyaldehyde.
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Synthesis of (2S,3R)-3-amino-2-hydroxydecanoic Acid and (3R,4R)-3-amino-4-hydroxyazepane from D-Isoascorbic Acid
Tetrahedron: Asymmetry, 1996Co-Authors: Arounarith Tuch, Michèle Sanière, Yves Le Merrer, Jean-claude DepezayAbstract:Abstract Taking advantage of the high functionality of an enantiopure protected syn -2 R -amino-1,3,4-triol derivative, easily available on a multigram scale from D-Isoascorbic Acid, several biologically active compounds have been synthesized such as the (2 S ,3 R )-3-amino-2-hydroxydecanoic Acid (AHDA), the N -terminal moiety of microginin, and the (3 R ,4 R )-3-amino-4-hydroxyazepane, the ophiocordin and balanol core structure.
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enantiopure hydroxylactones from l ascorbic and d Isoascorbic Acids part i synthesis of muricatacin
Tetrahedron, 1995Co-Authors: Michèle Sanière, Isabelle Charvet, Yves Le Merrer, Jean-claude DepezayAbstract:Abstract From D-Isoascorbic Acid, via a formal bis-epoxide equivalent with a C-2 axis of symmetry, two possible syntheses of the (−)-Muricatacin are described.
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Enantiopure hydroxylactones from L-ascorbic and D-Isoascorbic Acids. Part I. Synthesis of (−)-muricatacin
Tetrahedron, 1995Co-Authors: Michèle Sanière, Yves Le Merrer, Isabelle Charvet, Jean-claude DepezayAbstract:Abstract From D-Isoascorbic Acid, via a formal bis-epoxide equivalent with a C-2 axis of symmetry, two possible syntheses of the (−)-Muricatacin are described.
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Synthesis of (-)-Muricatacin and (-)-(5R,6S)-6-acetoxy-5-hexadecanolide, the Mosquito oviposition attractant pheromone, from D-Isoascorbic Acid
Tetrahedron Letters, 1994Co-Authors: Christine Gravier-pelletier, Michèle Sanière, Yves Le Merrer, Isabelle Charvet, Jean-claude DepezayAbstract:Abstract From D -Isoascorbic Acid, a general approach to enantiomerically pure hydroxy γ-butyro and δ-valero lactones, (-)-Muricatacin and (-)-(5 R ,6 S )-6-acetoxy-5-hexadecanolide, via a four carbon atoms bis-epoxide equivalent, is reported.
