ascorbic-acid and gluconic-acid

ascorbic-acid has been researched along with gluconic-acid* in 19 studies

Reviews

1 review(s) available for ascorbic-acid and gluconic-acid

ArticleYear
Biochemistry and biotechnological applications of Gluconobacter strains.
    Applied microbiology and biotechnology, 2002, Volume: 60, Issue:3

    The genus Gluconobacter belongs to the group of acetic acid bacteria, which are characterized by their ability to incompletely oxidize a wide range of carbohydrates and alcohols. The corresponding products (aldehydes, ketones and organic acids) are excreted almost completely into the medium. In most cases, the reactions are catalyzed by dehydrogenases connected to the respiratory chain. Since the reactive centers of the enzymes are oriented towards the periplasmic space, transport of substrates and products into, and out of, the cell is not necessary. Thus, rapid accumulation of incompletely oxidized products in the medium is facilitated. These organisms are able to grow in highly concentrated sugar solutions and at low pH-values. High oxidation rates correlate with low biomass production, which makes Gluconobacter strains interesting organisms for industrial applications. Modern fermentation processes, such as the production of L-sorbose (vitamin C synthesis) and 6-amino- L-sorbose (synthesis of the antidiabetic drug miglitol) are carried out with members of this genus. Other important products are dihydroxyacetone, gluconate and ketogluconates. The bacteria belonging to the genus Gluconobacter exhibit extraordinary uniqueness not only in their biochemistry but also in their growth behavior and response to extreme culture conditions. This uniqueness makes them ideal organisms for microbial process development.

    Topics: 1-Deoxynojirimycin; Acetic Acid; Ascorbic Acid; Biotechnology; Carbohydrate Metabolism; Genome, Bacterial; Gluconates; Gluconobacter; Glucosamine; Hydrogen-Ion Concentration; Imino Pyranoses

2002

Trials

6 trial(s) available for ascorbic-acid and gluconic-acid

ArticleYear
Comparison of Ferric Sodium EDTA in Combination with Vitamin C, Folic Acid, Copper Gluconate, Zinc Gluconate, and Selenomethionine as Therapeutic Option for Chronic Kidney Disease Patients with Improvement in Inflammatory Status.
    Nutrients, 2022, May-19, Volume: 14, Issue:10

    Anemia is one of the most frequent and earliest complications of chronic kidney disease (CKD), which impacts a patient’s quality of life and increases the risk of adverse clinical outcomes. Patients’ inflammatory status is strictly related to the occurrence of functional iron deficiency anemia (IDA) because this causes an increase in hepcidin levels with the consequent inhibition of iron absorption and release from cellular stores into blood circulation. The aim of this study was to evaluate the use of the new oral formulation based on ferric sodium EDTA in combination with vitamin C, folic acid, copper gluconate, zinc gluconate, and selenomethionine (Ferachel Forte®) in patients with moderate CKD and functional IDA, analyzing the inflammatory status in addition to iron blood parameters, in comparison with oral ferrous sulfate and liposomal iron therapies. Sixty-two elderly patients were randomly allocated to one of the following oral treatments for 6 months: ferrous sulfate (Group 1; N = 20), ferric sodium EDTA in combination (Group 2; N = 22), and ferric liposomal formulation (Group 3; N = 20). The evaluated parameters included iron profile parameters of hemoglobin (Hb), sideremia, ferritin, transferrin saturation, C-reactive protein (CRP), and hepcidin. The results showed that in Group 1, there were no improvements. In Group 2, there were statistically significant (p < 0.001) improvements in all evaluated parameters. Finally, in Group 3, there were significant improvements in all evaluated parameters except for hepcidin, which was less than that of Group 2 patients. In conclusion, the findings showed the superior efficacy of the formulation based on ferric sodium EDTA over the other oral iron sources, and that this formulation can contribute to reducing the systemic inflammatory status in patients with CKD.

    Topics: Aged; Anemia, Iron-Deficiency; Antioxidants; Ascorbic Acid; Edetic Acid; Folic Acid; Gluconates; Hepcidins; Humans; Iron; Quality of Life; Renal Insufficiency, Chronic; Selenomethionine; Sodium; Vitamins

2022
Effect of High-Dose Zinc and Ascorbic Acid Supplementation vs Usual Care on Symptom Length and Reduction Among Ambulatory Patients With SARS-CoV-2 Infection: The COVID A to Z Randomized Clinical Trial.
    JAMA network open, 2021, 02-01, Volume: 4, Issue:2

    There is limited evidence regarding early treatment of novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to mitigate symptom progression.. To examine whether high-dose zinc and/or high-dose ascorbic acid reduce the severity or duration of symptoms compared with usual care among ambulatory patients with SARS-CoV-2 infection.. This multicenter, single health system randomized clinical factorial open-label trial enrolled 214 adult patients with a diagnosis of SARS-CoV-2 infection confirmed with a polymerase chain reaction assay who received outpatient care in sites in Ohio and Florida. The trial was conducted from April 27, 2020, to October 14, 2020.. Patients were randomized in a 1:1:1:1 allocation ratio to receive either 10 days of zinc gluconate (50 mg), ascorbic acid (8000 mg), both agents, or standard of care.. The primary end point was the number of days required to reach a 50% reduction in symptoms, including severity of fever, cough, shortness of breath, and fatigue (rated on a 4-point scale for each symptom). Secondary end points included days required to reach a total symptom severity score of 0, cumulative severity score at day 5, hospitalizations, deaths, adjunctive prescribed medications, and adverse effects of the study supplements.. A total of 214 patients were randomized, with a mean (SD) age of 45.2 (14.6) years and 132 (61.7%) women. The study was stopped for a low conditional power for benefit with no significant difference among the 4 groups for the primary end point. Patients who received usual care without supplementation achieved a 50% reduction in symptoms at a mean (SD) of 6.7 (4.4) days compared with 5.5 (3.7) days for the ascorbic acid group, 5.9 (4.9) days for the zinc gluconate group, and 5.5 (3.4) days for the group receiving both (overall P = .45). There was no significant difference in secondary outcomes among the treatment groups.. In this randomized clinical trial of ambulatory patients diagnosed with SARS-CoV-2 infection, treatment with high-dose zinc gluconate, ascorbic acid, or a combination of the 2 supplements did not significantly decrease the duration of symptoms compared with standard of care.. ClinicalTrials.gov Identifier: NCT04342728.

    Topics: Adult; Ambulatory Care; Antioxidants; Ascorbic Acid; Cough; COVID-19; COVID-19 Drug Treatment; Dietary Supplements; Dyspnea; Fatigue; Female; Fever; Gluconates; Humans; Male; Middle Aged; SARS-CoV-2; Severity of Illness Index; Standard of Care; Trace Elements; Treatment Outcome; Zinc

2021
Effects of vitamin C, vitamin E, zinc gluconate, and selenomethionine supplementation on muscle function and oxidative stress biomarkers in patients with facioscapulohumeral dystrophy: a double-blind randomized controlled clinical trial.
    Free radical biology & medicine, 2015, Volume: 81

    Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant disease characterized by progressive weakness and atrophy of specific skeletal muscles. As growing evidence suggests that oxidative stress may contribute to FSHD pathology, antioxidants that might modulate or delay oxidative insults could help in maintaining FSHD muscle function. Our primary objective was to test whether oral administration of vitamin C, vitamin E, zinc gluconate, and selenomethionine could improve the physical performance of patients with FSHD. Adult patients with FSHD (n=53) were enrolled at Montpellier University Hospital (France) in a randomized, double-blind, placebo-controlled pilot clinical trial. Patients were randomly assigned to receive 500 mg vitamin C, 400mg vitamin E, 25mg zinc gluconate and 200 μg selenomethionine (n=26), or matching placebo (n=27) once a day for 17 weeks. Primary outcomes were changes in the two-minute walking test (2-MWT), maximal voluntary contraction, and endurance limit time of the dominant and nondominant quadriceps (MVCQD, MVCQND, TlimQD, and TlimQND, respectively) after 17 weeks of treatment. Secondary outcomes were changes in the antioxidant status and oxidative stress markers. Although 2-MWT, MVCQ, and TlimQ were all significantly improved in the supplemented group at the end of the treatment compared to baseline, only MVCQ and TlimQ variations were significantly different between groups (MVCQD: P=0.011; MVCQND: P=0.004; TlimQD: P=0.028; TlimQND: P=0.011). Similarly, the vitamin C (P<0.001), vitamin E as α-tocopherol (P<0.001), vitamin C/vitamin E ratio (P=0.017), vitamin E γ/α ratio (P=0.022) and lipid peroxides (P<0.001) variations were significantly different between groups. In conclusion, vitamin E, vitamin C, zinc, and selenium supplementation has no significant effect on the 2-MWT, but improves MVCQ and TlimQ of both quadriceps by enhancing the antioxidant defenses and reducing oxidative stress. This trial was registered at clinicaltrials.gov (number: NCT01596803).

    Topics: Administration, Oral; Adult; Ascorbic Acid; Dietary Supplements; Double-Blind Method; Female; Gait; Gluconates; Humans; Male; Middle Aged; Muscle Contraction; Muscle, Skeletal; Muscular Dystrophy, Facioscapulohumeral; Oxidative Stress; Physical Endurance; Pilot Projects; Selenomethionine; Vitamin E; Walking

2015
Double-blind, placebo-controlled trial comparing effects of supplementation of two micronutrient sprinkles on fatty acid status in Cambodian infants.
    Journal of pediatric gastroenterology and nutrition, 2007, Volume: 44, Issue:1

    Infants in developing countries require early dietary interventions to prevent nutritional deficiencies, above all protein, energy, iron and zinc. To what extent these interventions may affect the fatty acid (FA) status is still unknown.. To examine and compare the effects of 2 micronutrient "sprinkles" supplementations (iron 12.5 mg + folic acid 150 microg, iron/folate and iron 12.5 mg + folic acid 150 microg + zinc 5 mg + vitamins A, C and D3, mineral/micronutrient [MMN]) versus placebo on the FA status of Cambodian infants.. A total of 204 infants age 6 mo and living in Kompong Chhnang Province, Cambodia, were randomly assigned to receive daily supplementation of MMN (n = 68) and iron/folate (n = 68) or placebo (n = 68) for a 12-mo period in powder form as sprinkles. At the end of the intervention period, FAs in the range of 16 to 24 C were determined in blood drops absorbed on a strip collected from 182 subjects, and values among the 3 intervention subgroups and those of 21 Italian 18-mo-old, normal-growing infants as the reference group were compared.. At the end of the supplementation trial, higher levels of the 2 essential FAs (EFAs) (linoleic acid, 18:2n-6, and alpha-linolenic acid, 18:3n-3) were found in the MMN group. No differences occurred for the major longer chain derivatives of both EFAs arachidonic acid (20:4n-6) and docosahexaenoic acid (22:6n-3). In MMN supplemented Cambodians, blood levels of linoleic acid approached those of Italian infants, and in addition their alpha-linolenic acid levels were improved. Cambodian infants, mostly still breast-fed through the second year of life, showed significantly higher levels of long-chain derivatives of both the n-6 and the n-3 series compared with Italians.. Supplementation with iron, folic acid, zinc and vitamins was associated with an increase of linoleic acid and alpha-linolenic acid levels in Cambodian infants versus placebo, without significant changes in the concentrations of their longer chain derivatives, resulting in a FA status closer to Italian counterparts for the essential polyunsaturated FA levels. The iron/folate-treated infants showed no differences compared with the other 2 groups. Studies are needed to differentiate the potential effects of the supplemented micronutrients on the FA status.

    Topics: alpha-Linolenic Acid; Anemia, Iron-Deficiency; Ascorbic Acid; Cambodia; Child Development; Cholecalciferol; Dietary Supplements; Double-Blind Method; Female; Folic Acid; Fumarates; Gluconates; Humans; Infant; Iron Compounds; Italy; Linoleic Acid; Longitudinal Studies; Male; Micronutrients; Polysaccharides; Vitamin A

2007
Demonstrating zinc and iron bioavailability from intrinsically labeled microencapsulated ferrous fumarate and zinc gluconate Sprinkles in young children.
    The Journal of nutrition, 2006, Volume: 136, Issue:4

    Nutrient-nutrient interactions are an important consideration for any multiple-micronutrient formulation, including Sprinkles, a home-fortification strategy to control anemia. The objectives of this randomized controlled trial were as follows: 1) to compare the absorption of zinc at 2 doses given as Sprinkles; and 2) to examine the effect of zinc and ascorbic acid (AA) on iron absorption from Sprinkles. Seventy-five children aged 12-24 mo were randomly assigned to the following groups: 1) 5 mg of labeled zinc (67Zn) with 50 mg AA (LoZn group); b) 10 mg of labeled zinc (67Zn) with 50 mg AA (HiZn group); or 3) 5 mg zinc with no AA (control). All groups contained 30 mg of labeled iron (57Fe). Intravenous infusions labeled with 70Zn (LoZn and HiZn groups) and 58Fe (control) were administered. Blood was drawn at baseline, 48 h and 14 d later. The percentage of zinc absorbed did not differ between LoZn (geometric mean = 6.4%; min-max: 1.7-14.6) and HiZn (geometric mean = 7.5%; min-max: 3.3-18.0) groups. However, total zinc absorbed was significantly different between the LoZn (geometric mean = 0.31 mg; min-max: 0.08-0.73) and HiZn (geometric mean = 0.82 mg; min-max: 0.33-1.82) groups (P = 0.0004). Geometric mean percentage iron absorption values did not differ between the LoZn (5.9%; min-max: 0.8-21) and HiZn (4.4%; min-max: 0.6-12.3) groups and between the LoZn and control groups (5.0%; min-max: 1.4-24). We conclude that zinc in the form of Sprinkles has a low bioavailability, yet provides adequate amounts of absorbed zinc in young children, and that there is no effect of zinc or AA on iron absorption from the given formulations of Sprinkles.

    Topics: Absorption; Ascorbic Acid; Biological Availability; Diet; Drug Compounding; Ferrous Compounds; Ghana; Gluconates; Hemoglobins; Humans; Infant; Infant Nutritional Physiological Phenomena; Iron Isotopes; Iron, Dietary; Zinc; Zinc Isotopes

2006
The influence of orally-administered vitamin C or zinc on the absorption of and the biological response to lead.
    Journal of occupational medicine. : official publication of the Industrial Medical Association, 1983, Volume: 25, Issue:9

    A single-blind study was performed on male workers from a primary lead smelter to determine whether a daily oral supplement of vitamin C (1 g vitamin C orally once a day, five times a week for 20 weeks) or zinc (60 mg zinc as zinc gluconate once a day, five times a week for eight weeks) influences the absorption of and the biological (hematological and renal) response to lead. The vitamin C and the zinc study groups comprised 39 and 11 workers, respectively. Their blood levels of lead at the start of the experiment ranged from 28.9 to 76.4 micrograms/100 ml. A matched control group receiving a placebo was followed simultaneously. The results demonstrate that, in workers whose exposure to inorganic lead is moderate and who do not suffer from nutritional deficiencies, oral supplementation of vitamin C or zinc does not influence the metabolism and biological action of lead.

    Topics: Absorption; Administration, Oral; Adult; Ascorbic Acid; Gluconates; Humans; Lead; Male; Middle Aged; Occupational Diseases

1983

Other Studies

12 other study(ies) available for ascorbic-acid and gluconic-acid

ArticleYear
Quantitative 1HNMR Spectroscopy: Analysis of Zinc Gluconate in Utozinc® Tablets, a Mixture of Zinc Gluconate and Vitamin C.
    Journal of AOAC International, 2022, Dec-22, Volume: 106, Issue:1

    Zinc is an essential metal for humans and plays key roles in several biological events such as immunity, allergy, growth, and inflammation. The deficiency in zinc causes an increased infection rate with pathogens. Organo-zincates such as zinc gluconate are known for better absorption compared with their inorganic zinc salts. Its role in enhancing the immune system has driven a huge demand for organo-zinc supplements and in the treatment protocol of coronavirus disease, the causative agent of the COVID-19 pandemic.. Herein, we report on a quantitative analysis of zinc gluconate in the authentic form in presence of vitamin C, and the method was applied to their dosage form (Utozinc® tablets). The method is simple, accurate, and validated according to ICH guidelines.. Quantification of zinc gluconate formulated with vitamin C (Utozinc tablets) using Q-1HNMR. Maleic acid and deuterium oxide were used as internal standards and solvents, respectively.. The linearity range, the limit of detection and quantification, stability, precision, and accuracy, were validated. The validation of the method within five concentration levels (from 10 to 50 mg/0.5 mL D2O) afforded a limit of detection of 4.58 mg/mL, a quantification limit of 15.27 mg/mL, and excellent linearity.. The method proposed in the present study is simple, fast, nondestructive, and accurate. Zinc gluconate quantification values obtained by the Q-1HNMR method were found to show an acceptable correlation with those obtained by the thin-layer chromatographic technique.. The method was successfully applied to Utozinc tablets, and the results were compared with the reported reference pharmacopeial method. The salt exchange between maleic acid (IS) and zinc gluconate was tested by noticing the change in the chemical shift of IS and zinc gluconate.

    Topics: Ascorbic Acid; COVID-19; Humans; Pandemics; Spectrum Analysis; Tablets; Vitamins; Zinc

2022
[Progress in vitamin C biosynthesis related dehydrogenases].
    Sheng wu gong cheng xue bao = Chinese journal of biotechnology, 2021, Jun-25, Volume: 37, Issue:6

    Vitamin C is an essential vitamin for human beings. It has a huge market in the fields of food and pharmaceuticals. 2-keto-L-gulonic acid is an important precursor to produce vitamin C by microbial fermentation in industrial. In microbial fermentations, the L-sorbose pathway and the D-gluconate pathway have been the focus of research because of high yield. This article aims at stating recent research progress in dehydrogenases related to biosynthesis of vitamin C in the L-sorbose pathway and the D-gluconate pathway. The properties of dehydrogenase in terms of localization, substrate specificity, cofactors, and electron transport carrier are elaborated. And then, the main problems and strategies are reviewed in the L-sorbose pathway and in the D-gluconate pathway. Finally, future research on the dehydrogenases in the biosynthesis of vitamin C through L-sorbose pathway and D-gluconate pathway is discussed.. 维生素C是一种人体必需的维生素,在食品制药等领域拥有巨大的市场。工业上维生素C主要以微生物发酵生产的2-酮基-L-古龙酸为前体,然后通过内酯化反应获得。微生物发酵中,山梨糖途径和葡萄糖酸途径因为转化率高一直是研究的热点。文中从维生素C生物合成相关脱氢酶的角度阐述了:山梨糖途径和葡萄糖酸途径中关键脱氢酶在定位、底物谱、辅因子和电子传递上的特点;山梨糖途径和葡萄糖酸途径中面临的主要问题和改造策略等。最后讨论了维生素C生物合成中山梨糖途径和葡萄糖酸途径可能的研究方向。.

    Topics: Ascorbic Acid; Fermentation; Gluconates; Oxidoreductases; Sorbose

2021
A pilot study on secondary anemia in "frailty" patients treated with Ferric Sodium EDTA in combination with vitamin C, folic acid, copper gluconate, zinc gluconate and selenomethionine: safety of treatment explored by HRV non-linear analysis as predictive
    European review for medical and pharmacological sciences, 2020, Volume: 24, Issue:14

    Iron deficiency anemia (IDA) in patients with heart disease is correlated with decreased exercise capacity and poor health-related quality of life, and predicts worse cardiovascular outcomes, especially for elderly patients. IDA can worsen cardiac function that can be monitored with Heart Rate Variability (HRV) analysis, providing important information about cardiac health. In a recent study we explored the effect and the tolerability of the administration of Ferric Sodium EDTA in combination with vitamin C, folic acid, copper gluconate, zinc gluconate and selenomethionine (Ferachel Forte®) in "frailty" patients with secondary anemia and low kidney failure, by analysing the HRV frequency domain. The aim of the present study is the further confirmation of the safety of the already evaluated intervention, by analysing non-linear domain of HRV.. In this pilot study we enrolled 52 "frailty" elderly patients, with a recent diagnosis of secondary anemia due to iron deficiency, with Class II New York Heart Association (NYHA) hypertensive heart disease, low kidney failure, and atherosclerosis. The patients were divided in 2 groups: Group A (N=23 patients) received oral administration of Ferric Sodium EDTA in combination with vitamin C, folic acid, copper gluconate, zinc gluconate and selenomethionine (Ferachel Forte®) 2 tabs/day, containing 60 mg of Fe3+, for 24 days; Group B (N=29 patients) received intravenous administration of ferrous gluconate 63 mg/day added to saline solution, while they were hospitalized (15±5 days). We evaluated laboratory values of hemoglobin (Hb) and sideremia levels. Furthermore, we measured ECG signals before and after treatment, using non-linear analysis techniques.. Both intravenous and oral treatments evaluated in this study, were effective and safe about the cardiovascular risk in "frailty" elderly patients, as resulted from non-linear HRV analysis. Efficacy results showed that hemoglobin and sideremia levels after treatments are significantly increased. The HRV non-linear analysis showed that all parameters evaluated, except for the SD1 values in the Group A, were not affected by treatments, confirming the absence of cardiovascular risk of the therapy.. Non-linear HRV evaluation confirmed that oral administration of Ferric Sodium EDTA, in combination with vitamin C, folic acid, copper gluconate, zinc gluconate and selenomethionine (Ferachel forte®) did not impact the cardiovascular risk, without causing adverse events typically reported with other iron supplementation therapies, both oral and intravenous.

    Topics: Aged; Aged, 80 and over; Anemia, Iron-Deficiency; Ascorbic Acid; Drug Combinations; Edetic Acid; Female; Ferric Compounds; Folic Acid; Frail Elderly; Frailty; Gluconates; Heart Disease Risk Factors; Heart Diseases; Heart Rate; Humans; Iron Chelating Agents; Male; Pilot Projects; Renal Insufficiency; Risk Assessment; Selenomethionine; Time Factors; Treatment Outcome

2020
Vitamin C enhances bacterial cellulose production in Gluconacetobacter xylinus.
    Carbohydrate polymers, 2014, Volume: 99

    Influence of vitamin C (ascorbic acid) on bacterial cellulose (BC) production and crystal structure was studied using four strains of Gluconacetobacter xylinus (ATCC 10245, IFO 13693, 13772 and 13773). BC productivity of all strains was increased in presence of vitamin C (0.5% w/w), the average BC production reached 0.47 g/30 ml compared with 0.25 g/30 ml without vitamin C. Enhanced productivity is associated with a decrease in gluconic acid concentration that is produced from Gluconacetobacter xylinus during BC production. X-ray results showed that the crystallinity index of BC produced in presence of ascorbic acid was the lowest with remarkable change in d-spacing. These results were confirmed by using solid state (13)CNMR. The increase in BC yield in presence of vitamin C is due to its antioxidant behavior and confirms our past work on lignosulfonate influence on BC.

    Topics: Ascorbic Acid; Cellulose; Crystallization; Culture Media; Fermentation; Gluconacetobacter xylinus; Gluconates; Magnetic Resonance Spectroscopy; Polysaccharides, Bacterial; Spectroscopy, Fourier Transform Infrared

2014
A gold@silica core-shell nanoparticle-based surface-enhanced Raman scattering biosensor for label-free glucose detection.
    Analytica chimica acta, 2014, Feb-06, Volume: 811

    The gold nanostar@silica core-shell nanoparticles conjugated with glucose oxidase (GOx) enzyme molecules have been developed as the surface-enhanced Raman scattering (SERS) biosensor for label-free detection of glucose. The surface-immobilized GOx enzyme catalyzes the oxidation of glucose, producing hydrogen peroxide. Under laser excitation, the produced H2O2 molecules near the Au nanostar@silica nanoparticles generate a strong SERS signal, which is used to measure the glucose concentration. The SERS signal of nanostar@silica∼GOx nanoparticle-based sensing assay shows the dynamic response to the glucose concentration range from 25 μM to 25 mM in the aqueous solution with the limit of detection of 16 μM. The sensing assay does not show any interference when glucose co-exists with both ascorbic acid and uric acid. The sensor can be applied to a saliva sample.

    Topics: Ascorbic Acid; Biosensing Techniques; Chemistry Techniques, Analytical; Enzymes, Immobilized; Gluconates; Glucose; Glucose Oxidase; Gold; Hydrogen Peroxide; Metal Nanoparticles; Oxidation-Reduction; Silicon Dioxide; Spectrum Analysis, Raman; Uric Acid

2014
Functional characterisation of the active ascorbic acid transport into cerebrospinal fluid using primary cultured choroid plexus cells.
    Brain research, 2003, Oct-24, Volume: 988, Issue:1-2

    Crossing the blood-CSF barrier is an important pathway for certain nutrients to enter the CNS. Cultured choroid plexus epithelial cells are a potent model system to study active transport properties of this tissue in vitro. In the present study this in vitro model was used to analyse ascorbic acid transport across the blood-CSF barrier that is supposedly mediated by the Na(+)-dependent transporter SVCT2. The expression of SVCT2 in the cultured cells was proven by RT-PCR. Active transport across the cell monolayer resulted in ascorbic acid enrichment at the CSF mimicking side. Ascorbic acid transport and uptake were decreased to 13 and 27%, respectively, in the presence of 200 microM phloretin. Inhibition of both transepithelial substrate transport (to 7.5%) and cytoplasmatic uptake (to 20%) was observed in Na(+)-free medium indicating that a basolaterally located and Na(+)-dependent transporter mediates ascorbic acid uptake. Substituting Cl(-) by either iodide or D-gluconate increased ascorbic acid uptake by factors of 3.7 or 2.5, respectively. Similar observations were made when Na(+)-dependent myo-inositol transport was analysed. Additionally, in presence of 100 microM bumetanide, an inhibitor of Na(+)-Cl(-)-cotransport, indirectly increased ascorbic acid and myo-inositol transport rates were observed showing that ascorbic acid-Na(+)-cotransport might balance low intracellular Na(+) concentration.

    Topics: Animals; Ascorbic Acid; Blood-Brain Barrier; Bumetanide; Cells, Cultured; Cerebrospinal Fluid; Choroid Plexus; Enzyme Inhibitors; Gluconates; Organic Anion Transporters, Sodium-Dependent; Phloretin; Reverse Transcriptase Polymerase Chain Reaction; Sodium-Coupled Vitamin C Transporters; Swine; Symporters

2003
Identification and quantification of antioxidant components of honeys from various floral sources.
    Journal of agricultural and food chemistry, 2002, Oct-09, Volume: 50, Issue:21

    Little is known about the individual components of honey that are responsible for its antioxidant activity. The present study was carried out to characterize the phenolics and other antioxidants present in honeys from seven floral sources. Chromatograms of the phenolic nonpolar fraction of the honeys indicated that most honeys have similar but quantitatively different phenolic profiles. Many of the flavonoids and phenolic acids identified have been previously described as potent antioxidants. A linear correlation between phenolic content and ORAC activity was demonstrated (R(2) = 0.963, p < 0.0001). Honeys were separated by solid-phase extraction into four fractions for sugar removal and separation based on solubility to identify the relative contribution of each fraction to the antioxidant activity of honey. Antioxidant analysis of the different honey fractions suggested that the water-soluble fraction contained most of the antioxidant components. Specific water-soluble antioxidant components were quantified, including protein; gluconic acid; ascorbic acid; hydroxymethylfuraldehyde; and the combined activities of the enzymes glucose oxidase, catalase and peroxidase. Of these components, a significant correlation could be established only between protein content and ORAC activity (R(2) = 0.674, p = 0.024). In general, the antioxidant capacity of honey appeared to be a result of the combined activity of a wide range of compounds including phenolics, peptides, organic acids, enzymes, Maillard reaction products, and possibly other minor components. The phenolic compounds contributed significantly to the antioxidant capacity of honey but were not solely responsible for it.

    Topics: Antioxidants; Ascorbic Acid; Catalase; Chemical Fractionation; Chromatography, High Pressure Liquid; Chromatography, Liquid; Furaldehyde; Gluconates; Glucose Oxidase; Honey; Mass Spectrometry; Peroxidase; Phenols; Solubility; Water

2002
188Re DD-3B6/22 Fab' for use in therapy of ovarian cancer: labelling and animal studies.
    Nuclear medicine and biology, 1998, Volume: 25, Issue:7

    A fast and high yielding method of 188Re radiolabelling DD-3B6/22 Fab' is described. An inert atmosphere [N2(g)] and ascorbic acid was essential for preparation and storage of therapeutic levels (< or =2 GBq/mg) for up to 24 h. Immunoreactivity was greater than 75%. Pharmacokinetic studies in nu/nu mice demonstrated localisation of 188Re DD-3B6/22 Fab' was equivalent and correlated well with the behaviour observed for 99mTc DD-3B6/22 Fab' used to image ovarian cancer. Excellent stability at the target site in vivo supports the potential use of 188Re DD-3B6/22 Fab' in the therapy of ovarian cancer.

    Topics: Animals; Ascorbic Acid; Female; Gluconates; Immunoglobulin Fab Fragments; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Ovarian Neoplasms; Oxidation-Reduction; Radioimmunodetection; Radioisotopes; Radiopharmaceuticals; Radiotherapy; Rhenium; Technetium

1998
D-glucose and D-gluconate transport in vesicles from Pseudomonas putida.
    Canadian journal of biochemistry, 1980, Volume: 58, Issue:12

    Vesicles prepared from glucose-grown cells of Pseudomonas putida (ATCC, 12633) retain glucose oxidase (GOX) and gluconate dehydrogenase (GADH) activity and actively transport D-glucose, 2-deoxy-D-glucose (2DOG), 3-deoxy-3-fluoro-D-glucose (3FG), and D-gluconate by saturable processes. The transport of these substrates is stimulated by the addition of L-malate or reduced phenazine methosulphate (PMS). Vesicles prepared from succinate-grown cells of P. putida lose their capacity to transport D-glucose, 2DOG, and 3FG by a saturable process. The transport and accumulation of D-gluconate, however, is retained with a KX value of 65 microM and a Vmax of 1.0 nmol . mg protein-1 . min-1. The rate of D-gluconate transport is stimulated by the addition of reduced PMS of L-malate with a reduction in the KX value to 42.0 microM. Respirometric studies with these vesicles indicate the presence of an active GOX and L-malate dehydrogenase but a defective GADH. Thus a reductase activity is detected in the presence of D-gluconate and either 2,6-dichloroindophenol (DCIP) or ferricyanide, as measured by a decrease in absorbance at 500 and 420 nm, respectively. Measurements on these vesicles with the oxygen electrode, however, indicate that no electron transfer from GADH to oxygen occurs. This is in contrast to the results with glucose-grown vesicles or with L-malate or D-glucose as substrates in the succinate-grown vesicles. A comparison between glucose and gluconate oxidase activity in native and detergent-treated vesicles is made. The significance of these results in relation to the presence of a glucose carrier in P. putida and other pseudomonads is presented.

    Topics: Ascorbic Acid; Biological Transport, Active; Deoxyglucose; Gluconates; Glucose; Kinetics; Malates; Methylphenazonium Methosulfate; Oxygen Consumption; Pseudomonas; Spectrophotometry

1980
Studies on 5-keto-D-gluconate obtained by fermentation relating to L-ascorbic acid. I. Catalytic reduction of 5-keto-D-gluconate to L-idonate.
    The Journal of vitaminology, 1960, Sep-10, Volume: 6

    Topics: Ascorbic Acid; Carbohydrate Metabolism; Catalysis; Fermentation; Gluconates; Sugar Acids

1960
About ascorbic acid and its association with calcium gluconate.
    Farmalecta, 1949, Volume: 3, Issue:49

    Topics: Ascorbic Acid; Calcium; Calcium Compounds; Calcium, Dietary; Gluconates

1949
Treatment Of Asthma With Levorotatory Ascorbic Acid Combined With Intravenous Calcium Gluconate.
    Bulletin mensuel - Societe de medecine militaire francaise, 1948, Volume: 42, Issue:2

    Topics: Ascorbic Acid; Asthma; Calcium; Calcium Compounds; Calcium, Dietary; Gluconates

1948