- Strategy for in Situ Imaging of Cellular Alkaline Phosphatase Activity Using Gold Nanoflower Probe and Localized Surface Plasmon Resonance Technique
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In this work, a simple and ultrasensitive localized surface plasmon resonance (LSPR) method that use Au nanoflowers (AuNFs) as a probe was designed for in situ monitoring of alkaline phosphatase (ALP) activity. The AuNFs were fabricated by hydrogen tetrechloroaurate-induced oxidative disruption of polydopamine-coated Au nanoparticles (AuNPs), and subsequently, growth of Au nanopetals on AuNPs occurred. The as-prepared AuNFs showed a much higher LSPR capability and stronger scattering color change than AuNPs. The strategy for in situ cellular ALP activity detection relied on the deposition of Ag on the AuNFs surface, which changed the morphology of AuNFs and led to a tremendous LSPR response and scattering color change. The deposition of Ag shell on AuNFs was related to ALP activity, where ALP catalyzed the hydrolysis of l-ascorbic acid 2-phosphate sesquimagnesium salt hydrate to form l-ascorbic acid (AA), and then AA reduced Ag+ to Ag and deposited onto AuNFs. With this concept, the ALP activity could be monitored with a detection limit of 0.03 μU L-1. Meanwhile, the ALP activity of single HepG2 cells and HEK 293 cells was tracked with a proposed approach, which indicated the trace expression level of ALP in HEK 293T cell and overexpressed level of ALP in HepG2 cells. After treatment with drugs, the cellular ALP activity of HepG2 cells was decreased with the treating time and dose increasing. Therefore, the proposed strategy could be used for tracking the cellular ALP activity, which paved a new avenue for cell studies and held great potential for discovering novel ALP-based drugs applications.
- Wang, Kan,Jiang, Ling,Zhang, Fen,Wei, Yuanqing,Wang, Kang,Wang, Huaisheng,Qi, Zhengjian,Liu, Songqin
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- In Situ Fluorogenic Reaction Generated via Ascorbic Acid for the Construction of Universal Sensing Platform
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A highly fluorescent emission reaction between terephthalic acid (PTA) and ascorbic acid (AA) via simple control of the reaction temperature was first revealed with the detailed formation mechanism and various characterizations including electron paramagnetic resonance and mass spectrometry. Based on the AA-responsive emission, the alkaline phosphatase (ALP) triggered the transformation of l-ascorbic acid 2-phosphate trisodium salt to AA was integrated with the present system for developing a sensitive, selective, and universal platform. The monitoring of the activity of ALP and the fabrication of ALP-based enzyme-linked immunoassay (ELISA) with carcinoembryonic antigen (CEA) as the model target was performed. The fluorescence intensity correlated well to the CEA concentration in the ranges of 0.25-30 ng/mL, with a detection limit of 0.08 ng/mL. Such a facile protocol based on the fluorescent reaction between PTA and AA without the assistance of catalysis of nanomaterials avoided the laborious synthesis procedure and provided a direct strategy for the early clinical diagnosis coupled with ALP-related catalysis.
- Fan, Yongchao,Lv, Mengmeng,Xue, Yuan,Li, Jing,Wang, Erkang
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- An efficient three step synthesis of vitamin C from L-galactono-1,4-lactone, a by-product of the sugar industry
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An efficient and short synthesis of vitamin C has been accomplished from L-galactono-1,4-lactone via methyl 3,5:4,6-di-O-ethylidine-L-galactonate.
- Csiba,Cleophax,Petit,Gero
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Read Online
- Redox turnover of organometallic B12 cofactors recycles vitamin C: Sulfur assisted reduction of dehydroascorbic acid by cob(II)alamin
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This work reports the reactivity of cob(II)alamin (Cbl(II)) toward reduction of dehydroascorbic (DHA) to ascorbic acid (AA) mediated by sulfur-containing compounds such as glutathione (GSH) and thiocyanate. The reaction supported by GSH proceeded more efficiently than with SCN?. Our findings demonstrate new aspects of interactions between vitamins B12 and C. It has been accepted that simultaneous presence of these vitamins results in their decomposition (viz., irreversible modification of the corrin ring of Cbl and oxidation of AA). We have shown, however, that Cbl(II), the biologically active one-electron reduction product of methyl-Cbl (MeCbl) and adenosyl-Cbl (AdoCbl), is capable of recovering AA in the presence of natural sulfur-containing ligands, within a process that can occur in?vivo without glutathione spending, both in a stoichiometric and catalytic manner. Our studies highlight the redox versatility of Cbl(II) and expands the repertoire of reactions whereby redox turnover of the unique B12 organometallic cofactors MeCbl and AdoCbl generates Cbl(II), which in turn recycles oxidized vitamin C.
- Dereven'kov, Ilia A.,Hannibal, Luciana,Dürr, Maximilian,Salnikov, Denis S.,Bui Thi, Thu Thuy,Makarov, Sergei V.,Koifman, Oscar I.,Ivanovi?-Burmazovi?, Ivana
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- Interconversion between dehydro-L-ascorbic acid and L-ascorbic acid.
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L-Ascorbic acid (AA) plays an important role in biological systems as an electron donor. Erythorbic acid (EA) is the epimer of AA and has chemical characteristics very similar to those of AA. It is demonstrated in the present study by 1H-NMR that dehydro-L-ascorbic acid (DAA) was reduced by EA under neutral conditions but not acidic, and that dehydroerythorbic acid (DEA) was also reduced by AA under the same conditions. These reactions also occurred at a low concentration close to the concentration of AA in such biological tissue as the liver. Furthermore, the interconversion of DAA and AA at neutral pH and low concentration was also confirmed by radioluminography. These results suggest the interconversion between DAA and AA in vivo.
- Nishikawa,Kurata
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Read Online
- Fluorescence Immunoassay Based on the Alkaline Phosphatase Triggered in Situ Fluorogenic Reaction of o-Phenylenediamine and Ascorbic Acid
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Inspired by the special reducing capability of ascorbic acid (AA), ascorbic acid 2-phosphate (AA2P) has been extensively utilized as a substrate in current alkaline phosphatase (ALP) activity assays owing to the ALP-triggered transformation of AA2P into AA. However, such assays usually require AA-related complicated and laborious synthesis and/or signal generation procedures. Herein, we report an interesting in situ fluorogenic interaction between o-phenylenediamine (OPD) and AA, which inspires us to put forward a novel and simple AA2P/OPD-participated fluorescence turn-on ALP activity assay for the first time, and then the corresponding ALP-based fluorescence enzyme-linked immunosorbent assay (ELISA) has also been developed by means of the conventional ELISA platforms. According to the convenient and facile detection process with clear response mechanism, our fluorogenic reaction-based assay exhibits good sensitivity, selectivity, and excellent sensing performance, which ensures fluorescence ELISA to potentially be applied in clinical diagnosis by employing a well-studied biomarker of hepatocellular carcinoma, α-fetoprotein (AFP) as the model analyte. Such original ELISA via in situ formation of fluorophore from scratch gives a new sight to develop other potential immunoassay platforms in early clinical diagnosis by controlling the target antigens in the near future.
- Zhao, Dan,Li, Juan,Peng, Chuanyun,Zhu, Shuyun,Sun, Jian,Yang, Xiurong
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- A multicolor immunosensor for sensitive visual detection of breast cancer biomarker based on sensitive nadh-ascorbic-acid-mediated growth of gold nanobipyramids
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Many studies have demonstrated that the extracellular domain of human epidermal growth factor receptor 2 (HER2 ECD) level in serum can act as a breast cancer biomarker and serve as a monitoring neoadjuvant therapy of breast cancer. In this study, we developed a sensitive ascorbic acid (AA)-mediated AuNBPs (gold nanobipyramids) growth method with NADH (reduced nicotinamide adenine dinucleotide I) assistance, and we further fabricated a high-resolution multicolor immunosensor for sensitive visual detection of HER2 ECD in serum by using AuNBPs as signal and antibody as recognition probe. The NADH-assisted AA-mediated method effectively suppressed color formation in the blank and greatly improved the sensitivity of mediating AuNBPs growth, allowing us to use a low concentration of AA to mediate AuNBPs growth to generate more colorful and clearer color changes. The proposed multicolor immunosensor has higher resolution and more color changes corresponding to HER2 ECD concentrations. It can be used to detect as low as 0.5 ng/mL of HER2 ECD by bare eye observation and 0.05 ng/mL of HER2 ECD by UV-visible spectrophotometry. Using the immunosensor, we have successfully detected HER2 ECD in human serum with a recovery of 94%-96% and an RSD (n = 5) 5%. The results obtained with our immunosensor were consistent with those obtained with ELISA, verifying the immunosensor has good accuracy. The immunosensor exhibited a vivid multicolor change, has low visual detection limit, excellent specificity and reproducibility, and robust resistance to matrix. All the above features makes our immunosensor a promising assay for the early diagnosis of HER2-dependent breast cancers in clinical diagnosis.
- Wang, Zongwen,Chen, Qian,Zhong, Yingying,Yu, Xinhui,Wu, Yongning,Fu, FengFu
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- In Situ Exsolution of Noble-Metal Nanoparticles on Perovskites as Enhanced Peroxidase Mimics for Bioanalysis
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Various transition-metal oxide (TMO)-based nanomaterials have been explored as peroxidase mimics. However, the moderate peroxidase-like activity of TMOs limited their widespread use. Decorating highly active noble-metal nanozymes on the surface of TMOs can not only enhance the peroxidase-like activity of TMOs but also prevent the small-sized metal nanoparticles (NPs) from aggregation. Herein, in situ exsolution of noble-metal NPs (i.e., Ir and Ru) from A-site-deficient perovskite oxides (i.e., chemical formula La0.9B0.9B'0.1O3-d, B = Mn/Fe, B' = Ir/Ru) under a reducing atmosphere was achieved for preparing noble-metal NPs/perovskite composites. The exsolved NPs were socketed on the surface of parent perovskite oxides, which significantly enhanced the stability of metal NPs. In addition, the peroxidase-like activity of perovskite oxides increased remarkably after NPs egress. We then used the optimized Ir/LMIO with high stability and excellent peroxidase-like activity to develop a colorimetric assay for the determination of alkaline phosphatase (ALP). Benefiting from the remarkable peroxidase-like activity of Ir/LMIO, the sensing platform exhibited a wide linear range. The practical application of the colorimetric sensing method was demonstrated by detecting the ALP in serum samples. This work not only provides new insights into the synthesis of highly active peroxidase-like nanozymes but expands their applications for constructing a high-performance biosensing platform.
- Jiang, Xiaoqian,Wang, Xiaoyu,Lin, Anqi,Wei, Hui
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- Phosphate-triggered ratiometric fluoroimmunoassay based on nanobody-alkaline phosphatase fusion for sensitive detection of 1-naphthol for the exposure assessment of pesticide carbaryl
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The excessive use of carbaryl has resulted in the risk of its exposure. In this study, we isolated six nanobodies (Nbs) from a camelid phage display library against the biomarker of carbaryl, 1-naphthol (1-NAP). Owing to its characteristics of easy genetic modifications, we produced a nanobody-alkaline phosphatase (Nb-CC4-ALP) fusion protein with good stability. A dual-emission system based ratiometric fluoroimmunoassay (RFIA) for quick and highly sensitive determination of 1-NAP was developed. Silicon nanoparticles (SiNPs) was used as an internal reference and for aggregation-induced emission enhancement (AIEE) of gold nanoclusters (AuNCs), while AuNCs could be quenched by MnO2 via oxidation. In the presence of ALP, ascorbic acid phosphate (AAP) can be transformed into ascorbic acid (AA), the later can etch MnO2 to recover the fluorescence of the AuNCs. Based on optimal conditions, the proposed assay showed 220-fold sensitivity improvement in comparison with conventional monoclonal antibody-based ELISA. The recovery test of urine samples and the validation by standard HPLC-FLD demonstrated the proposed assay was an ideal tool for screening 1-NAP and provided technical support for the monitoring of carbaryl exposure.
- Chen, Zi-Jian,Wu, Hui-Ling,Shen, Yu-Dong,Wang, Hong,Zhang, Yi-Feng,Hammock, Bruce,Li, Zhen-Feng,Luo, Lin,Lei, Hong-Tao,Xu, Zhen-Lin
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- C a process for the preparation of vitamin
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The invention relates to a preparation method of vitamin C. The preparation method comprises the following steps: by using gulonic acid inorganic salt or gulonic acid as the raw material, adding a 0-38 wt% hydrochloric acid solution, stirring, cooling, introducing HCl gas, heating, and keeping the temperature until the reaction finishes, thereby obtaining the vitamin C. The preparation method has the advantages of simple technique, short reaction time and more environment-friendly production environment, obviously enhances the vitamin C quality and is suitable for vigorous popularization.
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Paragraph 0049-0052
(2018/02/04)
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- COMPOSITION FOR FORMING COMPLEX, COMPLEX FORMED THEREFROM, AND COMPOSITION FOR ORAL ADMINISTRATION INCLUDING SAID COMPLEX
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Provide are a composition for forming a composite, the composition including a cellulose-based compound, a polyphenol-based compound, and a solvent, wherein an amount of the polyphenol-based compound is 1 to 40 parts by weight based on 100 parts by weight of the cellulose-based compound, a composite formed from the composition, and an orally ingestible composition including the composite. The composite has characteristics of being dissolved in a solvent in a various pH ranges depending on a mixing ratio of the cellulose-based compound and the polyphenol-based compound. Therefore, when the composite is used, a composite film may be easily prepared, and the composite film may be useful in medical or foods fields where film characteristics dependent on pH is required.
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- An easy 'Filter-and-Separate' method for enantioselective separation and chiral sensing of substrates using a biomimetic homochiral polymer
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We present a polyfluorene appended with protected l-glutamic acid that exhibited a reversible α-helix/β-sheet-like conformation and helical porous fibrous morphology mimicking the super-structure of proteins. The new homochiral polymer probe enabled efficient heterogeneous enantioselective separation and chiral sensing of a wide variety of substrates from their aqueous racemic mixture using an easy 'Filter-and-Separate' method.
- Senthilkumar,Asha
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supporting information
p. 8931 - 8934
(2015/05/27)
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- Ultrasensitive electroanalysis of low-level free micrornas in blood by maximum signal amplification of catalytic silver deposition using alkaline phosphatase-incorporated gold nanoclusters
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An ultrasensitive sandwich-type analysis method has been initially developed for probing low-level free microRNAs (miRNAs) in blood by a maximal signal amplification protocol of catalytic silver deposition. Gold nanoclusters (AuNCs) were first synthesized and in-site incorporated into alkaline phosphatase (ALP) to form the ALP-AuNCs. Unexpectedly, the so incorporated AuNCs could dramatically enhance the catalysis activities of ALP-AuNCs versus native ALP. A sandwiched hybridization protocol was then proposed using ALP-AuNCs as the catalytic labels of the DNA detection probes for targeting miRNAs that were magnetically caught from blood samples by DNA capture probes, followed by the catalytic ligation of two DNA probes complementary to the targets. Herein, the ALP-AuNC labels could act as the bicatalysts separately in the ALP-catalyzed substrate dephosphorylation reaction and the AuNCs-accelerated silver deposition reaction. The signal amplification of ALP-AuNCs-catalyzed silver deposition was thereby maximized to be measured by the electrochemical outputs. The developed electroanalysis strategy could allow for the ultrasensitive detection of free miRNAs in blood with the detection limit as low as 21.5 aM, including the accurate identification of single-base mutant levels in miRNAs. Such a sandwich-type analysis method may circumvent the bottlenecks of the current detection techniques in probing short-chain miRNAs. It would be tailored as an ultrasensitive detection candidate for low-level free miRNAs in blood toward the diagnosis of cancer and the warning or monitoring of cancer metastasis in the clinical laboratory.
- Si, Yanmei,Sun, Zongzhao,Zhang, Ning,Qi, Wei,Li, Shuying,Chen, Lijun,Wang, Hua
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p. 10406 - 10414
(2015/02/19)
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- Oxidation reactions of thymol: A pulse radiolysis and theoretical study
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The reactions of ?OH and O?-, with thymol, a monoterpene phenol and an antioxidant, were studied by pulse radiolysis technique and DFT calculations at B3LYP/6-31+G(d,p) level of theory. Thymol was found to efficiently scavenge OH radicals (k = 8.1 × 109 dm3 mol-1 s-1) to produce reducing adduct radicals, with an absorption maximum at 330 nm and oxidizing phenoxyl radicals, with absorption maxima at 390 and 410 nm. A major part of these adduct radicals was found to undergo water elimination, leading to phenoxyl radicals, and the process was catalyzed by OH- (or Na2HPO4). The rate of reaction of O?- with thymol was found to be comparatively low (k = 1.1 × 109 dm3 mol -1 s-1), producing H abstracted species of thymol as well as phenoxyl radicals. Further, these phenoxyl radicals of thymol were found to be repaired by ascorbate (k = 2.1 × 108 dm3 mol -1 s-1). To support the interpretation of the experimental results, DFT calculations were carried out. The transients (both adducts and H abstracted species) have been optimized in gas phase at B3LYP/6-31+G(d,p) level of calculation. The relative energy values and thermodynamic stability suggests that the ortho adduct (C6-OH adduct) to be most stable in the reaction of thymol with OH radicals, which favors the water elimination. However, theoretical calculations showed that C4 atom in thymol (para position) can also be the reaction center as it is the main contributor of HOMO. The absorption maxima (λmax) calculated from time-dependent density functional theory (TDDFT) for these transient species were close to those obtained experimentally. Finally, the redox potential value of thymol?/ thymol couple (0.98 V vs NHE) obtained by cyclic voltammetry is less than those of physiologically important oxidants, which reveals the antioxidant capacity of thymol, by scavenging these oxidants. The repair of the phenoxyl radicals of thymol with ascorbate together with the redox potential value makes it a potent antioxidant with minimum pro-oxidant effects.
- Venu,Naik,Sarkar,Aravind, Usha K.,Nijamudheen,Aravindakumar
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p. 291 - 299
(2013/03/14)
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- METHODS OF INCREASING THE EXPRESSION YIELD OF VITAMIN K-DEPENDENT PROTEINS
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The invention encompasses the use of one or more compounds selected from a list comprising i) reduced forms of vitamin K and/or ii) reduced forms of a vitamin K analog and/or iii) reduced forms of a vitamin K precursor for the expression of one or more functional vitamin K-dependent proteins in cell culture as well as processes for the fermentation of eucaryotic cells expressing one or more vitamin K-dependent proteins wherein one or more compounds selected from a list comprising i) reduced forms of vitamin K and/or ii) reduced forms of a vitamin K analog and/or iii) reduced forms of a vitamin K precursor are added to the cell culture medium before and/or during the fermentation process.
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- Titanium(IV) and vitamin C: Aqueous complexes of a bioactive form of Ti(IV)
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Ascorbic acid is among the biorelevant ligands that render Ti(IV) stable in aqueous solution. A series of pH-dependent titanium(IV) coordination complexes of l-ascorbic acid is described. Directed by spectropotentiometric methods, important aspects of the aqueous interactions in this system are investigated, including ligand binding mode, pH-dependent metal-ligand stoichiometry, and the importance of metal ion-promoted hydrolysis and the binding of hydroxide. Stability constants are determined for all metal ion-ligand-proton complexes by a process of model optimization and nonlinear least-squares fitting of the combined spectropotentiometric titration data to the log βMLH values in the model. A speciation diagram is generated from the set of stability constants described in the model. In the range pH 3-10, the aqueous speciation is characterized by the sequential appearance of the following complexes as a function of added base: Ti(asc)20 → Ti(asc) 32- → Ti(asc)2(OH)2 2- → Ti(asc)(OH)42-. These species dominate the speciation at pH 10, respectively, with minimum log stability constants (β values) of 25.70, 36.91, 16.43, and -6.91. Results from electrospray mass spectrometry, metal-ligand binding experiments, and kinetics measurements support the speciation, which is characterized by bidentate chelation of the ascorbate dianion to the titanium(IV) ion via proton displacement, and a pH-dependent metal-ligand binding motif of ligand addition followed by metal ion-promoted hydrolysis, stepwise ligand dissociation, and the concomitant binding of hydroxide ion. Additionally, the kinetics of ligand exchange of titanium ascorbate with citrate are reported to understand better the possible fate of titanium ascorbate under biologically relevant conditions.
- Buettner, Katherine M.,Collins, Joseph M.,Valentine, Ann M.
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p. 11030 - 11039,10
(2012/12/12)
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- HPLC Determination of ascorbic acid and dehydroascorbic acid in Chinese jujube
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A high-performance liquid chromatographic method for determination of ascorbic acid and dehydroascorbic acid in Chinese jujube was developed. The dehydroascorbic acid content in sample can be calculated by the difference between the total ascorbic acid (after dehydroascorbic acid reduction) and the ascorbic acid concentrations (before reduction). The method resulted linear up to 42 mg/L with precision of 1.09 % and mean recovery of 103.4 %. The least limit of detection and quantitation were 0.02 and 0.11 mg/L, respectively. The 0.1 % H3PO4 solution was opted as extracting solvent after analyzing the effect of pH on the efficiency of ascorbic acid extraction. Using of HPLC method, the ascorbic acid and dehydroascorbic acid contents in fruits of six cultivars of Chinese jujube were analyzed. The contents of ascorbic acid and dehydroascorbic acid varied from 225.10 to 424.74 mg/100g and 27.03 to 103.62 mg/100g, respectively, which revealed that fruits of Chinese jujube were good sources of both ascorbic acid and dehydroascorbic acid.
- Yan-Ru,Zhi-Hui,Meng-Jun
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experimental part
p. 3989 - 3992
(2012/01/13)
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- Glutathione transferases of Phanerochaete chrysosporium: S-glutathionyl-p-hydroquinone reductase belongs to a new structural class
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The white rot fungus Phanerochaete chrysosporium, a saprophytic basidiomycete, possesses a large number of cytosolic glutathione transferases, eight of them showing similarity to the Omega class. PcGSTO1 (subclass I, the bacterial homologs of which were recently proposed, based on their enzymatic function, to constitute a new class of glutathione transferase named S-glutathionyl-(chloro)hydroquinone reductases) and PcGSTO3 (subclass II related to mammalian homologs) have been investigated in this study. Biochemical investigations demonstrate that both enzymes are able to catalyze deglutathionylation reactions thanks to the presence of a catalytic cysteinyl residue. This reaction leads to the formation of a disulfide bridge between the conserved cysteine and the removed glutathione from their substrate. The substrate specificity of each isoform differs. In particular PcGSTO1, in contrast to PcGSTO3, was found to catalyze deglutathionylation of S-glutathionyl-p-hydroquinone substrates. The three-dimensional structure of PcGSTO1 presented here confirms the hypothesis that it belongs not only to a new biological class but also to a new structural class that we propose to name GST xi. Indeed, it shows specific features, the most striking ones being a new dimerization mode and a catalytic site that is buried due to the presence of long loops and that contains the catalytic cysteine.
- Meux, Edgar,Prosper, Pascalita,Ngadin, Andrew,Didierjean, Claude,Morel, Melanie,Dumarcay, Stephane,Lamant, Tiphaine,Jacquot, Jean-Pierre,Favier, Frederique,Gelhaye, Eric
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scheme or table
p. 9162 - 9173
(2012/02/16)
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- Novel enrichment methods for gallic acid esters including 1-O-galloy1-bata-D-glucose and mucic acid gallates medicaments, therapeutic applications and methods of treatment thereof
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Improved methods to prepare aqueous extracts of gallic acid esters including 1-O-galloyl-β-D-glucose (β-glucogallin) and other mucic acid gallates from the fruits of Emblica officinalis, wherein enrichment of gallic acid esters is achieved by Supercritical Fluid Extraction (SCFE) procedure, are disclosed. The use of such standardized extracts of gallic acid esters (greater than 40% w/w of gallic acid esters) in the manufacture of medicaments with diverse health benefits, is also disclosed.
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- SCAFFOLDS FOR FOLLICLE TRANSPLANTATION
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The present invention provides for a device comprising a scaffold composition, a bioactive composition and a bio-in-hibiting composition, wherein said bioactive and bio-inhibiting compositions are incorporated into or coated onto said scaffold composition, wherein said scaffold composition temporally supports survival and growth of resident follicles, migration and multiplication of stroma cells and spreading and organization of endothelial cells and new vessels wherein said bioactive composition regulates development of a resident follicle, formation of new blood vessels and chemoattraction and proliferation of stroma cells and wherein the bio-inhibiting composition regulates inhibition of the development of a second resident follicle. The presence of the bio-inhibiting composition within the scaffold is involved in the quiescence of the follicles in the primordial stage, which is important to restore fertility.
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- Determination of dehydroascorbic acid in mouse tissues and plasma by using tris(2-carboxyethyl)phosphine hydrochloride as reductant in metaphosphoric acid/ethylenediaminetetraacetic acid solution
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Ascorbic acid (AA) has a strong anti-oxidant function evident as its ability to scavenge superoxide radicals in vitro. Moreover, AA is an essential ingredient for post-translational proline hydroxylation of collagen molecules. Dehydroascorbic acid (DHA), the oxidized form of AA, is generated from these reactions. In this study, we describe an improved method for assessing DHA in biological samples. The use of 35mM tris(2-carboxyethyl)-phosphine hydrochloride (TCEP) as a reductant completely reduced DHA to AA after 2 h on ice in a 5% solution of metaphosphoric acid containing 1mM ethylenediaminetetraacetic acid (EDTA) at pH 1.5. This method enabled us to measure the DHA content in multiple tissues and plasma of 6-weeks-old mice. The percentages of DHA per total AA differed markedly among these tissues, i.e., from 0.8 to 19.5%. The lung, heart, spleen and plasma had the highest levels at more than 10% of DHA per total AA content, whereas the cerebrum, cerebellum, liver, kidney and small intestine had less than 5% of DHA per total AA content. This difference in DHA content may indicate an important disparity of oxidative stress levels among physiologic sites. Therefore, this improved method provides a useful standard for all DHA determinations.
- Sato, Yasunori,Uchiki, Takayuki,Iwama, Mizuki,Kishimoto, Yuki,Takahashi, Ryoya,Ishigami, Akihito
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experimental part
p. 364 - 369
(2011/05/05)
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- Signal-enhanced liquid-crystal DNA biosensors based on enzymatic metal deposition
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No cloudiness with a silver lining: Deposition of metallic silver on a liquid-crystal substrate with attached DNA strands greatly alters the surface topology and induces a homeotropic-to-tiled transition of the LC molecules surrounding them, resulting in an obvious change in appearance from dark to birefringent (see picture; Ag: spheres). This enzymatic silver deposition is an excellent signal-enhancement strategy for LC optical amplification.
- Tan, Hui,Yang, Shengyuan,Shen, Guoli,Yu, Ruqin,Wu, Zhaoyang
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supporting information; experimental part
p. 8608 - 8611
(2011/01/10)
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- Method For the Production of a Keratin-Binding Effector Molecule
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The invention relates to a method of producing keratin-binding effector molecules, and to intermediates and end-products of the method according to the invention and to the use of the keratin-binding effector molecules produced according to the invention in dermocosmetics. In addition, the invention relates to a method of applying dermocosmetically active ingredients to skin and/or hair and to a method of increasing the residence time of an active ingredient on skin and hair.
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- NUTRITIONAL FORMULATION
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The present invention relates to nutritional supplements that provide an adult with essential vitamins and minerals that may be lacking in the adult's diet and prevent chronic diseases, such as osteoporosis. A number of combinations of nutrients in set ratios are provided to increase the body's ability to absorb and use the nutrients. These combinations are important in helping the body reach the proper balance required for maximized function. Because adults over the age of 50 years have different nutritional needs, nutritional supplements specifically designed for them are also provided.
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- BIOOCOMPATIBLE POLYMER COMPOSITIONS
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The present invention provides a biocompatible prepolymer comprising hydrophilic and hydrophobic segments, wherein the hydrophobic segments have at least one ethylenically unsaturated functional group and at least 5% of the segments have two or more ethylenically unsaturated functional groups and water. The invention further provides a biocompatible prepolymer composition comprising hydrophilic and hydrophobic prepolymers, wherein at least one of the hydrophobic prepolymers has at least one ethylenically unsaturated functional group and at least 5% of the prepolymers have two or more ethylenically unsaturated functional groups and water. The invention further provides use of the prepolymer or prepolymer compositions of the invention in biomedical applications such as tissue engineering, as bone substitutes or scaffolds, and in wound treatment.
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- NO LAXATION, LOW FLATULENCE BULKING SYSTEM
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A no-laxation, low flatulence bulking system and a method for preparation of same is disclosed. Gelatin, pectins and gellan gum are combined to form a dry-blended mixture. A second set of ingredients comprising at least erithritol is combined. A first liquid mixture comprising modified polydextrose and water is formed. The first dry-blended mixture is added to the first liquid mixture, forming a first mix. The second dry-blended mixture is added to the first mix, dimethicone is added, and the combination is heated to a first predetermined temperature. The heat is then reduced to a second predetermined temperature, and a second liquid mixture comprised of at least one acid and water is added. The second liquid mixture also may preferably include fruit concentrate, flavor, color and/or sucralose. The resultant solution is then preferably stirred constantly and held in a kettle or mixing tank for panning or molding as desired.
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- MW-assisted Er(OTf)3-catalyzed mild cleavage of isopropylidene acetals in Tricky substrates
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Erbium(III) trifluoromethane sulfonate is proposed as a very gentle Lewis acid catalyst in a MW-assisted chemoselective method for the cleavage of isopropylidene acetals in awkward substrates by using pure water as the solvent.
- Procopio, Antonio,Gaspari, Marco,Nardi, Monica,Oliverio, Manuela,Romeo, Roberto
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p. 1961 - 1964
(2008/09/19)
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- PROCESS FOR RECOVERING ORGANIC COMPOUNDS FROM AQUEOUS STREAMS CONTAINING SAME
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A method for a liquid-liquid extraction of hydrophilic organic compounds from aqueous solutions thereof is described. The method generally includes intermixing a sufficient quantity of a specified glycol ether with the aqueous liquor at a first temperature to form a suspension comprising an aqueous raffinate phase and a glycol ether extract phase; separating the glycol ether extract phase from the aqueous raffinate phase; heating the glycol ether extract phase to a second, higher temperature to form a suspension comprising an aqueous extract phase containing a portion of the hydrophilic organic compound and a glycol ether raffinate phase; and separating this glycol ether raffinate phase from the aqueous extract phase. The selected glycol ether has an inverse solubility in water and the partition ratio, value K, for the hydrophilic organic compound is greater than 0.1. This method is useful for recovering valuable hydrophilic organic acids produced via fermentation or produced or used in various manufacturing processes.
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Page/Page column 14; 17
(2008/06/13)
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- Colloidal particles of different element composition for specific labeling purposes
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The invention relates to colloidal particles of differing elemental compositions with differing morphologies, and to methods of preparing same. The invention also provides applications of such colloidal particles as labels in microscopy, as staining agents, and as biomolecule or drug carriers.
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- Nutritional supplement
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A nutritional supplement is provided that is designed to provide nutritional benefits as well as to assist the body with detoxification. By providing a supplement that serves both of these functions, the present invention may enable persons to improve their overall wellness.
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- METHOD FOR THE SEPARATION OF ASCORBIC ACID FROM A POLAR SOLVENT CONTAINING ASCORBIC ACID AND 2-KETO-L-GULONIC ACID
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The invention relates to a method for the separation of ascorbic acid from a mixture containing ascorbic acid and 2-keto-L-gulonic acid in a polar, preferably aqueous solvent, by means of liquid/liquid extraction using an amide. The method preferably also comprises steps for the back-extraction of the ascorbic acid, recycling of the extraction solvent and/or the back extraction solvent and for isolation of the ascorbic acid from the back extraction solvent. The invention further relates to a method for the production of ascorbic acid from KGA and isolation of the ascorbic acid so produced.
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Page/Page column 19-20
(2008/06/13)
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- METHOD FOR EXTRACTING 2-KETONE-L-GULONIC ACID FROM A POLAR, PREFERABLY AQUEOUS SOLVENT
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The invention relates to a method for extracting 2-ketone-L-gulonic acids from a polar, preferably aqueous solvent, preferably from a solvent which contains a mixture of ascorbic acid and 2-ketone-L-gulonic acid, by means of liquid-liquid extraction with the aid of an extraction agent which contains a tertiary amine and a polar organic diluent. Preferably, the inventive method also comprises steps for retro-extracting the 2-ketone-L-gulonic acid and for returning the extraction agent. The invention also relates to a method for producing ascorbic acid from 2-ketone-L-gulonic acid and for isolating the thus produced ascorbic acid.
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Page/Page column 17
(2008/06/13)
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- POLYETHOXYLATED ASCORBIC ACID DERIVATIVES AS A NOVEL ANTIOXIDANT AND PROCESS FOR PREPARING THEREOF
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Provided with a novel ascorbic acid derivative represented by the formula (I) and a method for preparing the same:wherein R1 and R2 are different from each other and, independently H or -CH2CH2-(O-CH2-CH2)n-OR3, wherein n is an integer from 2 to 400; and R3 is a lower alkyl group having 1 to 10 carbon atoms. The novel ascorbic acid derivatives of this invention have excellent characteristics such as long-lasting anti-oxidation effect, high solubility in both water and organic solvents, and high stability in an aqueous solution. Furthermore, the novel ascorbic acid derivatives are useful for feed, food, cosmetic and pharmaceutical products due to their low toxicity and high thermal stability.
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- 4-(2-Pyridyl) piperizines having 5HT7 receptor agonist activity
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The present invention relates to compounds of the formula I wherein R1, R2, R3, X and Y are defined as in the specification. Those compounds are 5HT7 partial agonists and are useful in the treatment of several disorders of the central nervous system.
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- Vitamin and zinc monomethionine compositions
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A dietary supplement composition that contains zinc monomethionine in combination with vitamin A, vitamin C, vitamin D, and a bioflavonoid that is formulated to be optimally absorbed and to help maintain normal human system functions.
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- Phenoxybenzylamine derivatives as SSRls
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A compound of general formula (I) wherein R1 and R2 are H, C1-C6alkyl or (CH2)d(C3-C6cycloalkyl) wherein d=0, 1, 2 or 3; or R1 and R2 together with the nitrogen to which they are attached form an azetidine ring; Z or Y is —SR3 and the other Z or Y is halogen or —R3; wherein R3 is C1-C4 alkyl optionally substituted with fluorine; except that R3 is not CF3; or Z and Y are linked so that, together with the interconnecting atoms, Z and Y form a fused 5 to 7-membered carbocyclic or heterocyclic ring, and wherein when Z and Y form a heterocyclic ring, in addition to carbon atoms, the linkage contains one or two heteroatoms independently selected from oxygen, sulfur and nitrogen; R4 and R5, which may be the same or different, are: A—X, wherein A═—CH═CH— or —(CH2)p— where p is 0, 1 or 2; X is hydrogen, F, Cl, Br, I, CONR6R7, SO2NR6R7, SO2NHC(═O)R6, OH, C1-4alkoxy, NR8SO2R9, NO2, NR6R11, CN, CO2R10, CHO, SR10, S(O)R9 or SO2R10; or a 5- or 6-membered heterocyclic ring containing 1, 2 or 3 heteroatoms selected from N, S and O, optionally substituted independently by one or more R13; wherein R13 is hydroxy, C1-C4alkoxy, F, C1-C6alkyl, haloalkyl, haloalkoxy, —NH2, —NH(C1-C6alkyl) or —N(C1-C6alkyl)2.
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- METHOD FOR THE PRODUCTION OF L-ASCORBIC ACID BY LACTONISATION OF 2-KETO-L-GULONIC ACID OR S2-KETO-L-GULONATE ESTERS
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The invention relates to a process for the preparation of L-ascorbic acid, in which free 2-keto-L-gulonic acid or C3-C10-alkyl 2-keto-L-gulonate is lactonized under acidic conditions in the presence of a water-miscible solvent and where this solvent in situ forms a solvent in which the ascorbic acid formed is poorly soluble.
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- L-Galactono-γ-lactone dehydrogenase activity and vitamin C content in fresh-cut potatoes stored under controlled atmospheres
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L-Galactono-γ-lactone dehydrogenase (GLDH) activity and vitamin C content as ascorbic acid (AA) plus dehydroascorbic acid (DHA) were evaluated in five potato tuber cultivars (Agata, Altesse, Franceline, Manon, and Monalisa). The effect of fresh-cutting and subsequent refrigerated storage of Manon potato under different atmospheres (air, 20% CO2 + air, 100% N2, and vacuum packaging) on GLDH activity and vitamin C content was also determined. GLDH from the five potato tuber cultivars showed typical inhibition kinetics by high substrate concentration in the synthesis of AA from its physiological precursor L-galactonic acid-γ-lactone (GL). GLDH activity was not correlated with the corresponding vitamin C content in any potato tuber cultivar. GLDH from all the cultivars presented a major isoform with isoelectric point (IEP) 5, which changed to IEP = 4.3 after minimal processing. In addition, the GLDH-catalyzed synthesis of AA by the new isoform showed typical Michaelis kinetics, in which the enzyme became more efficient to catalyze the reaction. Whether the change in the isoform pattern was due to either post-translational modifications or de novo synthesis of a new isoenzyme remains unanswered. Fresh-cutting increased GLDH activity from 4.7-fold (vacuum packaging) to 11-fold (air) after 6 days. In addition, 100% of vitamin C content was retained in air and decreased in the rest of atmospheres after this storage period, following the sequence vacuum packaging (89%) > 100% N2 (78%) > 20% CO2 + air (63%). This tendency was correlated with the corresponding GLDH activity detected in each storage atmosphere, except in the case of 20% CO2 + air. Vacuum packaging proved to be the best storage condition, because fresh-cut potatoes did not turn brown and retained 89% of initial vitamin C content.
- Tudela, Juan Antonio,Hernandez, Jose Antonio,Gil, Maria Isabel,Espin, Juan Carlos
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p. 4296 - 4302
(2007/10/03)
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- Preparation of sodium-hydrogen exchanger type-1 inhibitors
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This invention relates to methods of preparing sodium-hydrogen exchanger type 1 (NHE-1) inhibitors of formula I′ 1intermediates of the NHE-1 inhibitors and a new almost colorless form of the NHE-1 inhibitor N-(5-cyclopropyl-1-quinolin-5-yl-1H-pyrazole-4-carbonyl)-guanidine.
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- Use of radical-scavenging compounds for treatment and prevention of NO-dependent microcirculation disorders
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A method of treatment of the human or non-human animal body for treating NO-dependent microcirculation disorders is disclosed, for example microcirculation disorders caused by metabolic diseases, such as elevated levels of homocystin-homocystein inflammatory reactions or autoimmune diseases, furthermore peripheral microcirculation disorders or microcirculation disorders associated with increased cell fragmentation, which method comprises administering to a human or non-human animal body in need of such treatment an effective amount of a pharmaceutical composition containing a substance which scavenges free radicals, e.g. a pyrimido-pyrimidine selected from Dipyridamole, Mopidamol and the pharmaceutically acceptable salts thereof, and the use such substance for the manufacture of a corresponding pharmaceutical composition, optionally in combination with an agent capable of increasing NO procution.
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- New combination of active ingredients containing alfuzosine and apomorphine
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The subject of the present invention is a new combination of active ingredients consisting of alfuzosine and apomorphine, and pharmaceutical compositions containing them, for ameliorating and/or treating erectile dysfunction in male patients.
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- Self-sensitized photooxygenation of 3,4-dialkoxyfurans to vitamin C or its derivatives
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Self-sensitized photooxygenation of 3,4-dialkoxyfurans 3a-d with molecular oxygen and UV- or sunlight at room temperature gave vitamin C derivatives 2a-d in good to excellent yields. Furan 3c, having photodegradable protecting groups, was also photooxygenated to give L-ascorbic acid (1) in a "one-pot" reaction. Furthermore, a novel photolytic transformation was developed for deuteration of furan 3b at the C-2 position with D2O to give furan 3d in 95% yield. Toxicity of furans 3a-c and butenolides 2a-c against human embryonic cell, murine embryo fibroblasts, normal fibroblasts, HeLa, and Vero cell lines in the presence of oxygen and indirect solar light was found to be much less than those of the antipsoriasis drugs anthralin and 8-methoxypsoralen.
- Hakimelahi,Jain,Tai Wei Ly,Chen,Ethiraj,Ru Hwu,Moshfegh
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p. 7067 - 7071
(2007/10/03)
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- Process for the preparation of L-ascorbic acid
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The invention relates to a process for the preparation of L-ascorbic acid, which comprises lactonizing a melt of alkyl 2-keto-L-gulonate under acidic conditions.
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- Compounds for cardiovascular treatment comprising multi-vitamin and anti-platelet aggregating agents and methods for making and using the same
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Compounds comprising multi-vitamins, zinc and an anti-platelet aggregating agent for the treatment of atherosclerotic cardiovascular disease (ASCVD) are disclosed. The compounds are provided in dosage form, and preferably include selected amounts of ascorbic acid, folic acid, vitamin E, vitamin B6 and vitamin B12. The anti-platelet aggregating agent preferably comprises aspirin. A protective coating is preferably provided between the aspirin and the other vitamin and mineral constituents. The dosages are effective in the treatment of ASCVD, and possess extended shelf lives.
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- Novel antioxidant agents deriving from molecular combinations of vitamins C and E analogues: 3,4-Dihydroxy-5(R)-[2(R,S)-(6-hydroxy-2,5,7,8-tetramethyl-chroman-2(R,S)-yl-methyl)-[1,3]dioxolan-4(S)-yl]-5H-furan-2-one and 3-O-octadecyl derivatives
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Molecular combinations of two antioxidants (i.e., ascorbic acid and the pharmacophore of α-tocopherol), namely the 2,3-dihydroxy-2,3-enono-1,4-lactone and the chromane residues, have been designed and tested for their radical scavenging activities. When evaluated for their capability to inhibit malondialdehyde (MDA) production in rat liver microsomal membranes, the 3,4-dihydroxy-5R-2(R,S)-(6-hydroxy-2,5,7,8-tetramethylchroman-2(R,S)yl-methyl)-1,3]dioxolan-4S-yl]-5H-furan-2-one (11a-d), exhibited an interesting activity. In particular the 5R,2R,2R,4S and 5R,2R,2S,4S isomers (11c,d) displayed a potent antioxidant effect compared to the respective synthetic α-tocopherol analogue (5) and natural α-tocopherol or ascorbic acid, used alone or in combination. Moreover, the mixture of stereoisomers 11a-d also proved to be effective in preventing damage induced by reperfusion on isolated rabbit heart, in particular at the higher concentration of 300 μM. In view of these results our study represents a new approach to potential therapeutic agents for applications in pathological events in which a free radical damage is involved. Design, synthesis and preliminary biological activity are discussed. Copyright (C) 2000 Elsevier Science Ltd.
- Manfredini, Stefano,Vertuani, Silvia,Manfredi, Barbara,Rossoni, Giuseppe,Calviello, Gabriella,Palozza, Paola
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p. 2791 - 2801
(2007/10/03)
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- Production of L-ascorbic acid
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L-ascorbic acid is produced by allowing an acid to act on 2-keto-L-gulonic acid in a mixture solvent of an inert organic solvent and an aliphatic ketone in the presence of water and a surfactant. The method produces L-ascorbic acid in a high yield 90% or more and is an industrially advantageous method.
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- Cis-1,2-Dihydrocatechols in chemical synthesis: First synthesis of L-ascorbic acid (vitamin C) from a non-carbohydrate source
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The cis-1,2-dihydrocatechol (2), which is obtained in enantiopure form by microbial oxidation of chlorobenzene, has been converted, via 3,5-O-benzylidene-L-gulono-1,4-lactone (8), into L-ascorbic acid (1).
- Banwell, Martin G.,Blakey, Simon,Harfoot, Gwion,Longmore, Robert W.
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p. 137 - 142
(2007/10/03)
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- Process for the preparation of ascorbic acid
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A process for the preparation of L-ascorbic acid by reacting 2-keto-L-gulonic acid with aqueous mineral acid in a solvent mixture containing an inert organic solvent, an aliphatic ketone and also an acid chloride.
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- First synthesis of L-ascorbic acid (vitamin C) from a non-carbohydrate source
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The enantiopure cis-1,2-dihydrocatechol 2, which is obtained by microbial oxidation of chlorobenzene, has been converted, via 3,5-O-benzylidene-L-gulonolactone (8), into L-ascorbic acid (1).
- Banwell, Martin,Blakey, Simon,Harfoot, Gwion,Longmore, Robert
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p. 3141 - 3142
(2007/10/03)
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- Process for producing L-ascorbic acid
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A process for producing L-ascorbic acid, which comprises reacting 2-keto-L-gulonic acid with an acid in an ether or an inert organic solvent containing an ether in the presence of water and a surfactant.
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