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Sample records for juice ascorbic acid

  1. Ascorbic Acid Determination in Natural Orange Juice: As a Teaching Tool of Coulometry and Polarography.

    Science.gov (United States)

    Bertotti, Mauro; And Others

    1995-01-01

    Describes an experiment designed to determine ascorbic acid concentrations in natural orange juice. The experiment is used with undergraduate pharmacy students to allow understanding of the principles of operation of the coulometer and polarograph. (DDR)

  2. Retention of ascorbic acid in fortified orange juice powers during storage

    Directory of Open Access Journals (Sweden)

    G. S. Siddappa

    1960-10-01

    Full Text Available Both Coorg and Sathgudi orange juice powders are good carriers for added ascorbic acid during prolonged storage at ordinary temperatures. There is not much difference between nitrogen and air packs as regards retention of ascorbic acid during storage. Nitrogen pack, however, helps to keep the power in a better free-flowing condition.

  3. Influence of refrigeration length and of sugar addition on ascorbic acid content in some natural juices

    OpenAIRE

    Marcel Avramiuc; Liviu Fartaies

    2009-01-01

    Following some studies concerning the main factors influencing the concentration of vitamins within food raw materials, especially ascorbic acid, this work tries to evidence the influence of the refrigeration temperature and of the sucrose addition on content of this vitamin in three types of natural juice. The biological material was represented by orange, strawberry and kivi natural juices, obtained from these fruits by means a crushing out process. For each type of juice there ...

  4. Ascorbic Acid Determination in Commercial Fruit Juice Samples by Cyclic Voltammetry

    Science.gov (United States)

    Pisoschi, Aurelia Magdalena; Danet, Andrei Florin; Kalinowski, Slawomir

    2008-01-01

    A method was developed for assessing ascorbic acid concentration in commercial fruit juice by cyclic voltammetry. The anodic oxidation peak for ascorbic acid occurs at about 490 mV on a Pt disc working electrode (versus SCE). The influence of the potential sweep speed on the peak height was studied. The obtained calibration graph shows a linear dependence between peak height and ascorbic acid concentration in the domain (0.1–10 mmol·L−1). The equation of the calibration graph was y = 6.391x + 0.1903 (where y represents the value of intensity measured for the anodic peak height, expressed as μA and x the analyte concentration, as mmol·L−1, r2 = 0.9995, r.s.d. = 1.14%, n = 10, Cascorbic acid = 2 mmol·L−1). The developed method was applied to ascorbic acid assessment in fruit juice. The ascorbic acid content determined ranged from 0.83 to 1.67 mmol·L−1 for orange juice, from 0.58 to 1.93 mmol·L−1 for lemon juice, and from 0.46 to 1.84 mmol·L−1 for grapefruit juice. Different ascorbic acid concentrations (from standard solutions) were added to the analysed samples, the degree of recovery being comprised between 94.35% and 104%. Ascorbic acid determination results obtained by cyclic voltammetry were compared with those obtained by the volumetric method with dichlorophenol indophenol. The results obtained by the two methods were in good agreement. PMID:19343183

  5. Retention of Ascorbic Acid and Solid Concentration via Centrifugal Freeze Concentration of Orange Juice

    Directory of Open Access Journals (Sweden)

    P. Orellana-Palma

    2017-01-01

    Full Text Available Freeze concentration of liquid foods produces high-quality concentrates while retaining the heat-labile compounds found in fresh samples. Centrifugal freeze concentration is a cryoconcentration method assisted by an external force, centrifugation, to enhance the separation of concentrate from the ice. When applying centrifugal freeze concentration to orange juice, after the third cryoconcentration cycle, the ascorbic acid content in the concentrate showed retention close to 70% of the initial value. After the third cycle, the solutes in the concentrate increased 4 times the initial value of the fresh sample with 70% efficiency. The color evaluation showed that the final concentrated fraction was darker than the fresh juice. The centrifugal freeze concentration in orange juice was effective for obtaining a high-quality concentrate with a higher concentration of solids and ascorbic acid retention.

  6. Degradation kinetic modelling of ascorbic acid and colour intensity in pasteurised blood orange juice during storage.

    Science.gov (United States)

    Remini, Hocine; Mertz, Christian; Belbahi, Amine; Achir, Nawel; Dornier, Manuel; Madani, Khodir

    2015-04-15

    The stability of ascorbic acid and colour intensity in pasteurised blood orange juice (Citrus sinensis [L.] Osbeck) during one month of storage was investigated at 4-37 °C. The effects of ascorbic acid fortification (at 100, 200 mg L(-1)) and deaeration, temperature/time storage on the kinetic behaviour were determined. Ascorbic acid was monitored by HPLC-DAD and colour intensity by spectrophotometric measurements. Degradation kinetics were best fitted by first-order reaction models for both ascorbic acid and colour intensity. Three models (Arrhenius, Eyring and Ball) were used to assess the temperature-dependent degradation. Following the Arrhenius model, activation energies were ranged from 51 to 135 kJ mol(-1) for ascorbic acid and from 49 to 99 kJ mol(-1) for colour intensity. The effect of storage temperature and deaeration are the most influent factors on kinetics degradation, while the fortification revealed no significant effect on ascorbic acid content and colour intensity.

  7. Influence of rutin and ascorbic acid in colour, plum anthocyanins and antioxidant capacity stability in model juices.

    Science.gov (United States)

    Hernández-Herrero, J A; Frutos, M J

    2015-04-15

    Model juices at pH 3.7 were prepared with different combinations of ascorbic acid, rutin (quercetin 3-rutinoside) and concentrated anthocyanin extract of plums (cv. Black Gold). The anthocyanins in the concentrated extract were cyanidin 3-glucoside and cyanidin 3-rutinoside, in a proportion of 76% and 24% respectively. The model juices were stored during 17 weeks in darkness at 20 °C. The colour stability was improved by the presence of rutin and strongly damaged by the ascorbic acid. The fortification of anthocyanin model juices with ascorbic acid originated the degradation of most of anthocyanins. However, anthocyanins improved ascorbic acid stability during storage. The copigmentation of anthocyanin and rutin showed a beneficial effect on colour stability from the 5 weeks of storage. In model juices prepared exclusively with purified plum extract a high correlation (R(2)=0.881) between anthocyanins and antioxidant capacity was found.

  8. Ascorbic Acid

    Science.gov (United States)

    Ascorbic acid is used to prevent and treat scurvy, a disease caused by a lack of vitamin C in ... Ascorbic acid comes in extended-release (long-acting) capsules and tablets, lozenges, syrup, chewable tablets, and liquid drops to ...

  9. HPLC Determination of Ascorbic Acid Using Luminol-Cu(Ⅱ) Chemiluminescence-Application to the Analysis of Juice Beverage

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The chemiluminescence (CL) of luminol-Cu(Ⅱ) was applied to HPLC determination of ascorbic acid, which was separated by a C18 reverse-phase column with a mobile phase of 0.25 mol/L HAc. The eluted ascorbic acid was mixed with 0.3 mmol/L luminol and 0.05 mol/L CuSO4. The light emission from the reaction of Cu(Ⅱ) oxidized ascorbic acid and luminol was detected by a modified luminometer. The detection limit was 3.6×10-6 mol/L for ascorbic acid at a S/N ratio of 3, and the linear calibration range was 2×10-4- 2×10-3 mol/L. The relative standard deviation for 5 replicate injections of 1×10-3 mol/L ascorbic acid was calculated as 4.3 %. The method was successfully applied to determination of ascorbic acid in juice beverage.

  10. Effect of high hydrostatic pressure on phenolic compounds, ascorbic acid and antioxidant activity in cashew apple juice

    Science.gov (United States)

    Queiroz, C.; Moreira, C. F. F.; Lavinas, F. C.; Lopes, M. L. M.; Fialho, E.; Valente-Mesquita, V. L.

    2010-12-01

    The cashew apple is native to Brazil, but there is insufficient information regarding the nutritional properties of this fruit. The objective of this study was to evaluate the impact of high pressure processing (HPP) at room temperature (25 °C) on phenolic compound and ascorbic acid contents and antioxidant capacity of cashew apple juice. This study showed that HPP at 250 or 400 MPa for 3, 5 and 7 min did not change pH, acidity, total soluble solids, ascorbic acid or hydrolysable polyphenol contents. However, juice pressurized for 3 and 5 min showed higher soluble polyphenol contents. Antioxidant capacity, measured by the ferric-reducing antioxidant power method, was not altered by HPP, but when treated at 250 MPa for 3 min, it resulted in an increased value when 2,2-diphenyl-1-picrylhydrazyl was used. These data demonstrate that HPP can be used in the food industry for the generation of products with higher nutritional quality.

  11. Phenolics and Ascorbic Acid Related to Antioxidant Activity of MaoFruit Juice and Their Thermal Stability Study (Review Article

    Directory of Open Access Journals (Sweden)

    Thitiya Sripakdee

    2017-02-01

    Full Text Available Antioxidantand/or anti-aging activities are always linedwith people’s minds as major potential benefits concerning human health in the recent commercial features for an economicworld of foodstuffs and medical uses. Total phenolics includingflavonoids and anthocyanins,and ascorbic acid in the Mao juices areclosely related to their antioxidant activity.Numerous research approaches on these functional foods, in particular the colored fruits and vegetableshave been investigated. Method validation and determination ofthe potential compounds have been increasingly developedwith highly sensitive and selective procedures and applications including thermal stability of the Mao juice.Their antioxidant activities obtained from different assays related to the contents of both phenolics and ascorbic acid in the anthocyanins-richMao juicesin Thailand are reported and discussed.

  12. Phenolics and Ascorbic Acid Related to Antioxidant Activity of MaoFruit Juice and Their Thermal Stability Study (Review Article)

    OpenAIRE

    Thitiya Sripakdee; Ratana Mahachai; Saksit Chanthai

    2017-01-01

    Antioxidantand/or anti-aging activities are always linedwith people’s minds as major potential benefits concerning human health in the recent commercial features for an economicworld of foodstuffs and medical uses. Total phenolics includingflavonoids and anthocyanins,and ascorbic acid in the Mao juices areclosely related to their antioxidant activity.Numerous research approaches on these functional foods, in particular the colored fruits and vegetableshave been investigated. Method validation...

  13. Amperometric microsensor for direct probing of ascorbic acid in human gastric juice.

    Science.gov (United States)

    Hutton, Emily A; Pauliukaitė, Rasa; Hocevar, Samo B; Ogorevc, Božidar; Smyth, Malcolm R

    2010-09-30

    This article reports on a novel microsensor for amperometric measurement of ascorbic acid (AA) under acidic conditions (pH 2) based on a carbon fiber microelectrode (CFME) modified with nickel oxide and ruthenium hexacyanoferrate (NiO-RuHCF). This sensing layer was deposited electrochemically in a two-step procedure involving an initial galvanostatic NiO deposition followed by a potentiodynamic RuHCF deposition from solutions containing the precursor salts. Several important parameters were examined to characterize and optimize the NiO-RuHCF sensing layer with respect to its current response to AA by using cyclic voltammetry, and scanning electron microscopy-energy dispersive X-ray spectroscopy methods. With the NiO-RuHCF coated CFME, the AA oxidation potential under acidic conditions was shifted to a less positive value for about 0.2 V (E(p) of ca. 0.23 V vs. Ag/AgCl) as compared to a bare CFME, which greatly improves the electrochemical selectivity. Using the hydrodynamic amperometry mode, the current vs. AA concentration in 0.01 M HCl, at a selected operating potential of 0.30 V, was found to be linear over a wide range of 10-1610 μM (n=22, r=0.999) with a calculated limit of detection of 1.0 μM. The measurement repeatability was satisfactory with a relative standard deviation (r.s.d.) ranging from 4% to 5% (n=6), depending on the AA concentration, and with a sensor-to-sensor reproducibility (r.s.d.) of 6.9% at 100 μM AA. The long-term reproducibility, using the same microsensor for 112 consecutive measurements of 20 μM AA over 11 h of periodic probing sets over 4 days, was 16.1% r.s.d., thus showing very good stability at low AA levels and suitability for use over a prolonged period of time. Moreover, using the proposed microsensor, additionally coated with a protective cellulose acetate membrane, the calibration plot obtained in the extremely complex matrix of real undiluted gastric juice was linear from 10 to 520 μM (n=14, r=0.998). These results

  14. Determination of creatinine, uric and ascorbic acid in bovine milk and orange juice by hydrophilic interaction HPLC.

    Science.gov (United States)

    Zuo, Ruiting; Zhou, Si; Zuo, Yuegang; Deng, Yiwei

    2015-09-01

    Creatinine (Cr), uric (UA) and ascorbic acid (AA) are common constituents in human fluids. Their abnormal concentrations in human fluids are associated with various diseases. Thus, apart from the endogenous formation in human body, it is also important to examine their sources from food products. In this study, a rapid and accurate HILIC method was developed for simultaneous determination of Cr, UA and AA in bovine milk and orange juice. Milk samples were pretreated by protein precipitation, centrifugation and filtration, followed by HPLC separation and quantification using a Waters Spherisorb S5NH2 column. The developed method has been successfully applied to determine the concentration of UA, AA and Cr in milk and fruit juice samples. The milk samples tested were found to contain UA and creatinine in the concentration range of 24.1-86.0 and 5.07-11.2 μg mL(-1), respectively. The orange juices contain AA over 212 μg mL(-1).

  15. The Study on the Change of Ascorbic Acid in the Fruit Juice of Phyllanthus emblica L. During Stored%余甘果汁贮藏中Vc含量变化的分析

    Institute of Scientific and Technical Information of China (English)

    甘瑾; 唐莉英; 赵苹

    2001-01-01

    实验测定了在不同条件下贮藏6个月的余甘果汁中Vc的含量,以掌握余甘果汁在贮藏期间的变化规律,实验结果表明,余甘果汁在贮藏期内,Vc含量随贮藏时间的延长而逐渐减少,其中大量接触空气是Vc减少的主要原因。另外,蔗糖加入余甘果汁,对Vc也有较好的保护作用。%The paper describs the chang law of ascorbic acid in fruit juice of Phyllanthus emblica L. The experiment method is that the fruit juice was stored in different conditions, and regularly determined the content of ascorbic acid. After six months, the result of the experiment indicated that the content of ascorbic acid in the fruit juice of Phyllanthus emblica L. was gradually decreased as time went on, and the reductive amount of ascorbic acid in fruit juice in sealed container was less than that in wide open container. In addition, the sugar which was added into the fruit juice could protect the ascorbic acid from damage.

  16. Simultaneous amperometric detection of ascorbic acid and antioxidant capacity in orange, blueberry and kiwi juice, by a telemetric system coupled with a fullerene- or nanotubes-modified ascorbate subtractive biosensor.

    Science.gov (United States)

    Barberis, Antonio; Spissu, Ylenia; Fadda, Angela; Azara, Emanuela; Bazzu, Gianfranco; Marceddu, Salvatore; Angioni, Alberto; Sanna, Daniele; Schirra, Mario; Serra, Pier Andrea

    2015-05-15

    Four fullerenes- or nanotubes-modified graphite sensor-biosensor systems (SBs), coupled with a dual-channel telemetric device, based on an ascorbate oxidase (AOx) biosensor, were developed for on line simultaneous amperometric detection of ascorbic acid (AA) and antioxidant capacity in blueberry, kiwi and orange juice. Fullerene C60 (FC60), fullerene C70 (FC70), single-walled carbon nanotubes (SWCN) and multi-walled carbon nanotubes (MWCN) increased the sensitivity of graphite toward AA and phenols 1.2, 1.5, 5.1 and 5.1 times respectively. Fullerenes combined with AOx improved the selectivity toward AA more than nanotubes, being able to hold a higher number of AOx molecules on the biosensor surface. The SBs work at an applied potential of +500 mV, in a concentration range between the LOD and 20 μM, with a response time of two minutes. The LOD is 0.10, 0.13, 0.20 and 0.22 μM for SBs modified with FC60, FC70, SWCN and MWCN respectively. Biosensors register lower AA currents than the sensors due to the enzyme capability to oxidize AA before it reaches the transductor surface. Phenols currents registered by sensors and biosensors did not differ. Based on the difference between sensor and biosensor recorded currents a AA selectivity index was developed as an indicator of specificity toward AA and of the capacity to distinguish between AA and phenols contribution to the antioxidant capacity. This value is almost zero for fullerene-modified SBs, 0.13 and 0.22 for SWCN- and MWCN-modified SBs respectively. The results of juices analysis performed with SBs were in accordance with reference methods.

  17. Ascorbic acid improves the antioxidant activity of European grape juices by improving the juices' ability to inhibit lipid peroxidation of human LDL in vitro

    DEFF Research Database (Denmark)

    Landbo, Anne-Katrine Regel; Meyer, Anne Boye Strunge

    2001-01-01

    Antioxidant activities of red and white European grape juices towards copper induced lipid oxidation of human low-density lipoproteins (LDL) were examined in vitro. LDL lipid peroxidation was assessed spectrophotometrically by monitoring the development of conjugated lipid hydroperoxides at 234 nm...

  18. Determinação simultânea dos ácidos orgânicos tartárico, málico, ascórbico e cítrico em polpas de acerola, açaí e caju e avaliação da estabilidade em sucos de caju Simulataneous determination of tartaric, malic, ascorbic and citric acids in acerola, açai and cashew pulps, and stability evaluation in cashew juices

    Directory of Open Access Journals (Sweden)

    Rodrigo Scherer

    2008-01-01

    Full Text Available The aim of the present study was determining the main organic acids in pulp and juices, as well as evaluating their stability, after opening the package, by liquid chromatography in a C18 column with isocratic elution and UV detection. In açaí pulp tartaric, malic and citric acids were found. Cashew samples presented all of the organic acids evaluated, besides high concentrations of ascorbic and malic acids. Acerola pulp had the highest ascorbic acid concentration. A small decrease in organic acid content during storage was observed. Malic and citric acids seem to be more stable than tartaric and ascorbic acids.

  19. 21 CFR 582.5013 - Ascorbic acid.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ascorbic acid. 582.5013 Section 582.5013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5013 Ascorbic acid. (a) Product. Ascorbic acid. 1 Amino acids listed in this subpart may...

  20. 21 CFR 182.8013 - Ascorbic acid.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ascorbic acid. 182.8013 Section 182.8013 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8013 Ascorbic acid. (a) Product. Ascorbic acid. (b) Conditions of use. This substance is generally recognized as safe when used...

  1. 21 CFR 182.3013 - Ascorbic acid.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ascorbic acid. 182.3013 Section 182.3013 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 182.3013 Ascorbic acid. (a) Product. Ascorbic acid. (b) Conditions of use. This substance is generally recognized as...

  2. 21 CFR 582.3013 - Ascorbic acid.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ascorbic acid. 582.3013 Section 582.3013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... Ascorbic acid. (a) Product. Ascorbic acid. (b) Conditions of use. This substance is generally recognized...

  3. Effects of ingestion of tomatoes, tomato juice and tomato purée on contents of lycopene isomers, tocopherols and ascorbic acid in human plasma as well as on lycopene isomer pattern.

    Science.gov (United States)

    Fröhlich, Kati; Kaufmann, Karin; Bitsch, Roland; Böhm, Volker

    2006-04-01

    Tomatoes are an important part of the diet. Lycopene, the predominant carotenoid in tomatoes, is hypothesised to mainly mediate the health benefits of tomato products. Anticancer activity of tomato products and lycopene has been suggested by numerous studies. The aim of the present study was to investigate the effect of ingestion of three different tomato-based foodstuffs on plasma contents of lycopene, tocopherols and ascorbic acid. Because isomers of lycopene may have different biological activities, a special interest was to look how the lycopene isomer pattern is changed depending on the matrix of tomato products. Following a 2-week depletion phase volunteers ingested 12.5 mg lycopene/d for 4 weeks comprising tomatoes, tomato juice or tomato purée. The basal levels of lycopene in plasma were comparable for all groups and decreased significantly during the 2 weeks of depletion to approximately half of the basal values. Following intervention, plasma lycopene concentration increased significantly. Conversely, supplementation did not significantly affect levels of tocopherols and ascorbic acid in plasma. Regarding isomers of lycopene, the (Z)-lycopene:(all-E)-lycopene plasma isomer ratio was significantly changed during the study for all groups. A remarkable enrichment of the relative contents of (5Z)-lycopene was observed during the depletion period, which supports the hypothesis that lycopene (Z)-isomers are formed within the human body after ingestion of (all-E)-lycopene. After dietary intervention with lycopene-rich products the isomer ratios returned to those observed at the start of the study. Further investigations will clarify the process of isomerisation in more detail.

  4. Effects of genotype, latitude, and weather conditions on the composition of sugars, sugar alcohols, fruit acids, and ascorbic acid in sea buckthorn (Hippophaë rhamnoides ssp. mongolica) berry juice.

    Science.gov (United States)

    Zheng, Jie; Yang, Baoru; Trépanier, Martin; Kallio, Heikki

    2012-03-28

    Sea buckthorn berries (Hippophaë rhamnoides ssp. mongolica) of nine varieties were collected from three growth locations in five inconsecutive years (n = 152) to study the compositional differences of sugars, sugar alcohols, fruit acids, and ascorbic acid in berries of different genotypes. Fructose and glucose (major sugars) were highest in Chuiskaya and Vitaminaya among the varieties studied, respectively. Malic acid and quinic acid (major acids) were highest in Pertsik and Vitaminaya, respectively. Ascorbic acid was highest in Oranzhevaya and lowest in Vitaminaya. Berry samples of nine varieties collected from two growth locations in five years (n = 124) were combined to study the effects of latitude and weather conditions on the composition of H. rhamnoides ssp. mongolica. Sea buckthorn berries grown at lower latitude had higher levels of total sugar and sugar/acid ratio and a lower level of total acid and were supposed to have better sensory properties than those grown at higher latitude. Glucose, quinic acid, and ascorbic acid were hardly influenced by weather conditions. The other components showed various correlations with temperature, radiation, precipitation, and humidity variables. In addition, fructose, sucrose, and myo-inositol correlated positively with each other and showed negative correlation with malic acid on the basis of all the samples studied (n = 152).

  5. Sensitive spectrophotometric determination of ascorbic acid in drugs and foods using surface plasmon resonance band of silver nanoparticles

    Directory of Open Access Journals (Sweden)

    Kobra Zarei

    2015-12-01

    Full Text Available A simple and sensitive procedure was proposed for spectrophotometric determination of ascorbic acid. It was found that the reduction of Ag+ to silver nanoparticles (Ag-NPs by ascorbic acid in the presence of polyvinylpyrrolidone (PVP as a stabilizing agent produce very intense surface plasmon resonance peak of Ag-NPs. The plasmon absorbance of the Ag-NPs at λ = 440 nm allows the quantitative spectrophotometric detection of the ascorbic acid. The calibration curve was linear with concentration of ascorbic acid in the range of 0.5–60 μM. The detection limit was obtained as 0.08 μM. The influence of potential interfering substances on the determination of ascorbic acid was studied. The proposed method was successfully applied for the determination of ascorbic acid in some powdered drink mixtures, commercial orange juice, natural orange juice, vitamin C injection, effervescent tablet, and multivitamin tablet.

  6. Industrialized cashew juices: variation of ascorbic acid and other physicochemical parameters Sucos de caju industrializados: variação no teor de ácido ascórbico e em outros parâmetros físico-químicos

    Directory of Open Access Journals (Sweden)

    Christiane de Queiroz Pereira

    2008-12-01

    Full Text Available Commercial cashew apple juice is widely accepted in the Brazilian market. Cashew apple has high content of ascorbic acid, an important nutrient to human beings. Ascorbic acid content in food can be affected by processing and storage conditions. Commercial cashew apple juice samples, ready-to-drink and concentrated, were analyzed. The ascorbic acid content, total titratable acidity, total soluble solids, and pH of the juices were determined during storage at 4 °C after the containers were opened. The ascorbic acid content presented a great variability among the samples analyzed ranging from 37.3 to 46.3 mg.100 mL-1 in ready-to-drink juices and from 75.7 to 152 mg.100 mL-1 in concentrated juices. The storage of commercial cashew apple juices for 48 hours at 4 °C resulted in ascorbic acid losses of up to 8.8% for concentrated and 6.4% for ready-to-drink juices. The other parameters remained stable during storage. The results of this study point to the importance of considering ascorbic acid losses in commercial cashew apple juices which occurs after opening but before the expiration date expires.Sucos de caju industrializados são amplamente aceitos no mercado brasileiro. O caju contém alto teor de ácido ascórbico, importante nutriente para o ser humano. O teor deste nutriente pode ser afetado pelo processamento e pelas condições de estocagem dos alimentos. Foram analisadas amostras de sucos industrializados de caju, prontos para o consumo e concentrados. O teor de ácido ascórbico, a acidez total titulável, o teor de sólidos solúveis totais e o pH dos sucos foram determinados durante estocagem a 4 °C, após abertura das embalagens. Houve grande variabilidade no teor de ácido ascórbico entre as amostras, 37,3 a 46,3 mg.100 mL-1 nos sucos prontos para o consumo e 75,7 a 152 mg.100 mL-1 nos sucos concentrados. A estocagem dos sucos por 48 horas a 4 °C resultou em redução do teor de ácido ascórbico em até 8,8% para os concentrados

  7. Mercury excretion and intravenous ascorbic acid.

    Science.gov (United States)

    Dirks, M J; Davis, D R; Cheraskin, E; Jackson, J A

    1994-01-01

    We tested the hypothesis that intravenous ascorbic acid increases urinary excretion of mercury in subjects with low mercury levels from dental amalgam, food, and other sources. From 89 adult volunteers we selected 28 subjects with the highest mercury excretions (2 to 14 micrograms/24 h). We administered intravenous infusions of 500 ml lactated Ringer's solution with and without addition of 750 mg of ascorbic acid/kg body weight, up to 60 g ascorbic acid. Average mercury excretion during the 24 h after infusion of ascorbic acid was 4.0 +/- 0.5 micrograms (mean +/- SEM), which was not significantly more than after infusion of Ringer's solution alone (3.7 +/- 0.5 micrograms). Lead excretion was similarly unaffected. If ascorbic acid administered intravenously benefits some persons with suspected adverse reactions to mercury, the benefit in subjects similar to ours appears unrelated to short-term enhanced excretion of mercury or lead.

  8. Fate of the synergistic antioxidant system ascorbic acid, lecithin, and tocopherol in mayonnaise: Partion of ascorbic acid

    DEFF Research Database (Denmark)

    Meyer, Anne Merete Boye; Jacobsen, Charlotte Munch

    1996-01-01

    Meyer, A. S. & C. Jacobsen, 1996. Fate of the synergistic antioxidant system ascorbic acid, lecithin, and tocopherol in mayonnaise: Partion of ascorbic acid, J. Food Lipids, 3, 139-147.......Meyer, A. S. & C. Jacobsen, 1996. Fate of the synergistic antioxidant system ascorbic acid, lecithin, and tocopherol in mayonnaise: Partion of ascorbic acid, J. Food Lipids, 3, 139-147....

  9. Fate of the synergistic antioxidant system ascorbic acid, lecithin, and tocopherol in mayonnaise: Partion of ascorbic acid

    DEFF Research Database (Denmark)

    Meyer, Anne Merete Boye; Jacobsen, Charlotte Munch

    1996-01-01

    Meyer, A. S. & C. Jacobsen, 1996. Fate of the synergistic antioxidant system ascorbic acid, lecithin, and tocopherol in mayonnaise: Partion of ascorbic acid, J. Food Lipids, 3, 139-147.......Meyer, A. S. & C. Jacobsen, 1996. Fate of the synergistic antioxidant system ascorbic acid, lecithin, and tocopherol in mayonnaise: Partion of ascorbic acid, J. Food Lipids, 3, 139-147....

  10. Drug Nanoparticle Formulation Using Ascorbic Acid Derivatives

    Directory of Open Access Journals (Sweden)

    Kunikazu Moribe

    2011-01-01

    Full Text Available Drug nanoparticle formulation using ascorbic acid derivatives and its therapeutic uses have recently been introduced. Hydrophilic ascorbic acid derivatives such as ascorbyl glycoside have been used not only as antioxidants but also as food and pharmaceutical excipients. In addition to drug solubilization, drug nanoparticle formation was observed using ascorbyl glycoside. Hydrophobic ascorbic acid derivatives such as ascorbyl mono- and di-n-alkyl fatty acid derivatives are used either as drugs or carrier components. Ascorbyl n-alkyl fatty acid derivatives have been formulated as antioxidants or anticancer drugs for nanoparticle formulations such as micelles, microemulsions, and liposomes. ASC-P vesicles called aspasomes are submicron-sized particles that can encapsulate hydrophilic drugs. Several transdermal and injectable formulations of ascorbyl n-alkyl fatty acid derivatives were used, including ascorbyl palmitate.

  11. Impulsive mathematical modeling of ascorbic acid metabolism in healthy subjects.

    Science.gov (United States)

    Bachar, Mostafa; Raimann, Jochen G; Kotanko, Peter

    2016-03-07

    In this work, we develop an impulsive mathematical model of Vitamin C (ascorbic acid) metabolism in healthy subjects for daily intake over a long period of time. The model includes the dynamics of ascorbic acid plasma concentration, the ascorbic acid absorption in the intestines and a novel approach to quantify the glomerular excretion of ascorbic acid. We investigate qualitative and quantitative dynamics. We show the existence and uniqueness of the global asymptotic stability of the periodic solution. We also perform a numerical simulation for the entire time period based on published data reporting parameters reflecting ascorbic acid metabolism at different oral doses of ascorbic acid.

  12. Ascorbic acid: a nonradioactive extracellular space marker in canine heart

    National Research Council Canada - National Science Library

    Reil, G H; Frombach, R; Kownatzki, R; Quante, W; Lichtlen, P R

    1987-01-01

    The distribution pattern of ascorbic acid and L-[14C]ascorbic acid in myocardial tissue was compared with those of the classical radioactive extracellular space markers [3H]-inulin, [3H]sucrose, and Na82Br...

  13. Oxygen dependency of one-electron reactions generating ascorbate radicals and hydrogen peroxide from ascorbic acid.

    Science.gov (United States)

    Boatright, William L

    2016-04-01

    The effect of oxygen on the two separate one-electron reactions involved in the oxidation of ascorbic acid was investigated. The rate of ascorbate radical (Asc(-)) formation (and stability) was strongly dependent on the presence of oxygen. A product of ascorbic acid oxidation was measurable levels of hydrogen peroxide, as high as 32.5 μM from 100 μM ascorbic acid. Evidence for a feedback mechanism where hydrogen peroxide generated during the oxidation of ascorbic acid accelerates further oxidation of ascorbic acid is also presented. The second one-electron oxidation reaction of ascorbic acid leading to the disappearance of Asc(-) was also strongly inhibited in samples flushed with argon. In the range of 0.05-1.2 mM ascorbic acid, maximum levels of measurable hydrogen peroxide were achieved with an initial concentration of 0.2 mM ascorbic acid. Hydrogen peroxide generation was greatly diminished at ascorbic acid levels of 0.8 mM or above.

  14. 21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Nicotinamide-ascorbic acid complex. 172.315 Section... HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex. Nicotinamide-ascorbic acid complex may be safely used in accordance with the following prescribed...

  15. Higher transcription levels in ascorbic acid biosynthetic and recycling genes were associated with higher ascorbic acid accumulation in blueberry.

    Science.gov (United States)

    Liu, Fenghong; Wang, Lei; Gu, Liang; Zhao, Wei; Su, Hongyan; Cheng, Xianhao

    2015-12-01

    In our preliminary study, the ripe fruits of two highbush blueberry (Vaccinium corymbosum L.) cultivars, cv 'Berkeley' and cv 'Bluecrop', were found to contain different levels of ascorbic acid. However, factors responsible for these differences are still unknown. In the present study, ascorbic acid content in fruits was compared with expression profiles of ascorbic acid biosynthetic and recycling genes between 'Bluecrop' and 'Berkeley' cultivars. The results indicated that the l-galactose pathway was the predominant route of ascorbic acid biosynthesis in blueberry fruits. Moreover, higher expression levels of the ascorbic acid biosynthetic genes GME, GGP, and GLDH, as well as the recycling genes MDHAR and DHAR, were associated with higher ascorbic acid content in 'Bluecrop' compared with 'Berkeley', which indicated that a higher efficiency ascorbic acid biosynthesis and regeneration was likely to be responsible for the higher ascorbic acid accumulation in 'Bluecrop'. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Occurrence of L-Ascorbic Acid in Euglena gracilis z

    OpenAIRE

    1980-01-01

    Euglena gracilis synthesizes L-ascorbic acid. The content of total L-ascorbic acid in the cells grown photoautotrophically for 9 days in the stationary phase was 4.01 μmole/10^9 cells, corresponding to 4.25 mg per g dry weight. The oxidized form, dehydro-L-ascorbic acid was about 20% of total L-ascorbic acid. Illumination influenced the acid content markedly. From the present data, formation and physiological roles of L-ascorbic acid seem to be strongly affected by illumination.

  17. Sodium ascorbate improves yield of urinary steroids during hydrolysis with Helix pomatia juice.

    Science.gov (United States)

    Christakoudi, Sofia; Cowan, David A; Taylor, Norman F

    2008-03-01

    Urinary steroid profile analysis requires enzymatic hydrolysis of glucuronide and sulfate conjugates and this is achieved simultaneously using Helix pomatia juice (HPJ), but steroids with 3beta-hydroxy-5-ene structure undergo transformation and yield of 5alpha-reduced corticosteroid glucuronides is poor. We describe the use of sodium ascorbate to solve these problems and provide a basis for its mode of action. Steroid conjugates were extracted from urine, hydrolyzed in acetate buffer with HPJ and sodium ascorbate and analyzed as methyloxime-trimethylsilylether derivatives by gas chromatography-mass spectrometry. Ranges of temperature, pH and ascorbate, substrate and HPJ concentrations were compared for urine and pure standards. Activity of other antioxidants and that of bacterial cholesterol oxidase were examined. Helix pomatia enzyme preparations from different commercial sources were compared. Loss of 3beta-hydroxy-5-ene steroids was enzyme-dependant, since it required HPJ, was saturable, subject to substrate competition and heat-inactivated. Products were 3-oxo-4-ene steroids and 4,6-diene and 6-oxy derivatives of these but the latter were not formed from 3-oxo-4-ene precursors. Ascorbate, other antioxidants or oxygen exclusion diminished activity. These characteristics were shared by cholesterol oxidase. Yield of 5alpha-reduced steroids was diminished by pre-incubation of HPJ before ascorbate addition and this was reversed if ascorbate was added to the pre-incubation mixture. We conclude that transformation of 3beta-hydroxy-5-ene steroids by HPJ is due to cholesterol oxidase and is diminished by antioxidants or oxygen denial. Yield of 5alpha-reduced steroids is low due to oxidative damage of beta-glucuronidase during hydrolysis, prevented by ascorbate. These features are shared by most commercial Helix pomatia enzyme preparations tested.

  18. Dietary phenolic acids and ascorbic acid: Influence on acid-catalyzed nitrosative chemistry in the presence and absence of lipids.

    Science.gov (United States)

    Combet, Emilie; El Mesmari, Aziza; Preston, Tom; Crozier, Alan; McColl, Kenneth E L

    2010-03-15

    Acid-catalyzed nitrosation and production of potentially carcinogenic nitrosative species is focused at the gastroesophageal junction, where salivary nitrite, derived from dietary nitrate, encounters the gastric juice. Ascorbic acid provides protection by converting nitrosative species to nitric oxide (NO). However, NO may diffuse into adjacent lipid, where it reacts with O(2) to re-form nitrosative species and N-nitrosocompounds (NOC). In this way, ascorbic acid promotes acid nitrosation. Using a novel benchtop model representing the gastroesophageal junction, this study aimed to clarify the action of a range of water-soluble antioxidants on the nitrosative mechanisms in the presence or absence of lipids. Caffeic, ferulic, gallic, or chlorogenic and ascorbic acids were added individually to simulated gastric juice containing secondary amines, with or without lipid. NO and O(2) levels were monitored by electrochemical detection. NOC were measured in both aqueous and lipid phases by gas chromatography-tandem mass spectrometry. In the absence of lipids, all antioxidants tested inhibited nitrosation, ranging from 35.9 + or - 7.4% with gallic acid to 93 + or - 0.6% with ferulic acid. In the presence of lipids, the impact of each antioxidant on nitrosation was inversely correlated with the levels of NO they generated (R(2) = 0.95, pascorbic acid promoted nitrosation, whereas ferulic and caffeic acids markedly inhibited nitrosation.

  19. Efeito de diferentes processamentos sobre o teor de ácido ascórbico em suco de laranja utilizado na elaboração de bolo, pudim e geléia Effect of different processing methods on ascorbic acid content in orange juice used to make cakes, puddings and jelly

    Directory of Open Access Journals (Sweden)

    Patricia Teixeira da Silva

    2006-09-01

    Full Text Available Este estudo teve por objetivo avaliar a estabilidade do ácido ascórbico em suco de laranja cv. "Pêra" utilizado como ingrediente na elaboração de bolos, pudins e geléia. Os bolos e os pudins foram assados em forno convencional e de microondas, e a geléia foi elaborada em tacho aberto. Estas preparações foram submetidas a análises para determinação dos teores de ácido ascórbico e de sólidos solúveis totais, da acidez total titulável e do pH. Os teores de ácido ascórbico em bolos e pudins, quando comparados ao do suco de laranja in natura apresentaram redução de, respectivamente, 76,09% e 41,76%, quando assados em forno de microondas, e de 84,21% e 46,71%, quando assados em forno convencional. A geléia de laranja apresentou redução de 24,86% no teor de ácido ascórbico em relação ao suco de laranja in natura. A cocção de bolos e pudins realizada em forno de microondas proporcionou maior retenção do ácido ascórbico, quando comparada àquela realizada em forno convencional. Estas preparações apresentaram perda superior à da geléia, elaborada em tacho aberto. Foi observado, também, que os bolos perderam mais ácido ascórbico do que os pudins, em ambos os métodos de cocção avaliados.The aim of this study is to analyze the stability of ascorbic acid in orange juice cv. "Pera" used as an ingredient to prepare cakes, puddings and jelly. Cakes and puddings were baked in conventional and microwave ovens and the jelly was prepared in a pan without a lid. Ascorbic acid content, total soluble solids, total tritatable acidity and the pH were determined in all prepared foods. The AA content in cakes and puddings, when compared to the content of orange juice in natura had a reduction of 76.09% and 41.76%, respectively when baked in a microwave oven and of 84.21% and 46.71%, when baked in a conventional oven. Orange jelly showed a reduction of 24.76% in the ascorbic acid content related to orange juice in natura

  20. Evaluation of ascorbic acid in protecting labile folic acid derivatives.

    Science.gov (United States)

    Wilson, S D; Horne, D W

    1983-11-01

    The use of ascorbic acid as a reducing agent to protect labile, reduced derivatives of folic acid has been evaluated by high-performance liquid chromatographic separations and Lactobacillus casei microbiological assay of eluate fractions. Upon heating for 10 min at 100 degrees C, solutions of tetrahydropteroylglutamic acid (H4PteGlu) in 2% sodium ascorbate gave rise to 5,10-methylene-H4PteGlu and 5-methyl-H4PteGlu. H2PteGlu acid gave rise to 5-methyl-H4PteGlu and PteGlu. 10-Formyl-H4PteGlu gave rise to 5-formyl-H4PteGlu and 10-formyl-PteGlu. 5-Formyl-H4-PteGlu gave rise to a small amount of 10-formyl-PteGlu. 5-Methyl-H4PteGlu and PteGlu appeared stable to these conditions. These interconversions were not seen when solutions of these folate derivatives were kept at 0 degrees C in 1% ascorbate. These observations indicate that elevated temperatures are necessary for the interconversions of folates in ascorbate solutions. Assays of ascorbic acid solutions indicated the presence of formaldehyde (approximately equal to 6 mM). This was confirmed by the identification of 3,5-diacetyl-1,4-dihydrolutidine by UV, visible, and fluorescence spectroscopy and by thin-layer chromatography of chloroform extracts of the reaction mixture of ascorbic acid solutions, acetylacetone, and ammonium acetate. These results indicate that solutions of sodium ascorbate used at elevated temperatures are not suitable for extracting tissue for the subsequent assay of the individual folic acid derivatives.

  1. Evaluation of ascorbic acid in protecting labile folic acid derivatives.

    OpenAIRE

    1983-01-01

    The use of ascorbic acid as a reducing agent to protect labile, reduced derivatives of folic acid has been evaluated by high-performance liquid chromatographic separations and Lactobacillus casei microbiological assay of eluate fractions. Upon heating for 10 min at 100 degrees C, solutions of tetrahydropteroylglutamic acid (H4PteGlu) in 2% sodium ascorbate gave rise to 5,10-methylene-H4PteGlu and 5-methyl-H4PteGlu. H2PteGlu acid gave rise to 5-methyl-H4PteGlu and PteGlu. 10-Formyl-H4PteGlu ga...

  2. Final report of the safety assessment of L-Ascorbic Acid, Calcium Ascorbate, Magnesium Ascorbate, Magnesium Ascorbyl Phosphate, Sodium Ascorbate, and Sodium Ascorbyl Phosphate as used in cosmetics.

    Science.gov (United States)

    Elmore, Amy R

    2005-01-01

    L-Ascorbic Acid, Calcium Ascorbate, Magnesium Ascorbate, Magnesium Ascorbyl Phosphate, Sodium Ascorbate, and Sodium Ascorbyl Phosphate function in cosmetic formulations primarily as antioxidants. Ascorbic Acid is commonly called Vitamin C. Ascorbic Acid is used as an antioxidant and pH adjuster in a large variety of cosmetic formulations, over 3/4 of which were hair dyes and colors at concentrations between 0.3% and 0.6%. For other uses, the reported concentrations were either very low (Sodium Ascorbyl Phosphate functions as an antioxidant in cosmetic products and is used at concentrations ranging from 0.01% to 3%. Magnesium Ascorbyl Phosphate functions as an antioxidant in cosmetics and was reported being used at concentrations from 0.001% to 3%. Sodium Ascorbate also functions as an antioxidant in cosmetics at concentrations from 0.0003% to 0.3%. Related ingredients (Ascorbyl Palmitate, Ascorbyl Dipalmitate, Ascorbyl Stearate, Erythorbic Acid, and Sodium Erythorbate) have been previously reviewed by the Cosmetic Ingredient Review (CIR) Expert Panel and found "to be safe for use as cosmetic ingredients in the present practices of good use." Ascorbic Acid is a generally recognized as safe (GRAS) substance for use as a chemical preservative in foods and as a nutrient and/or dietary supplement. Calcium Ascorbate and Sodium Ascorbate are listed as GRAS substances for use as chemical preservatives. L-Ascorbic Acid is readily and reversibly oxidized to L-dehydroascorbic acid and both forms exist in equilibrium in the body. Permeation rates of Ascorbic Acid through whole and stripped mouse skin were 3.43 +/- 0.74 microg/cm(2)/h and 33.2 +/- 5.2 microg/cm(2)/h. Acute oral and parenteral studies in mice, rats, rabbits, guinea pigs, dogs, and cats demonstrated little toxicity. Ascorbic Acid and Sodium Ascorbate acted as a nitrosation inhibitor in several food and cosmetic product studies. No compound-related clinical signs or gross or microscopic pathological effects were

  3. Supplementation of Ascorbic Acid in Weanling Horses Following Prolonged Transportation

    Directory of Open Access Journals (Sweden)

    Michelle Stives

    2012-04-01

    Full Text Available Though horses synthesize ascorbic acid in their liver in amounts that meet their needs under normal circumstances, prolonged stress results in low plasma concentrations due to enhanced utilization and renal excretion and can reduce immune function. It was hypothesized that plasma ascorbic acid could be maintained in weanling horses by oral supplementation following prolonged transportation. Weanlings were supplemented with no ascorbic acid (Tx 0: n = 4, 5 grams ascorbic acid twice daily for 5 days (Tx 1: n = 4 or for 10 days (Tx 2: n = 4 following >50 hours of transportation. Supplementation caused slight (P < 0.2 increases in plasma ascorbic acid concentrations. Both supplemented groups had decreased (P < 0.05 plasma concentrations for 1 to 3 weeks following cessation of supplementation, possibly due to increased renal excretion or suppressed hepatic synthesis. Supplementation of ascorbic acid following prolonged stress will increase plasma concentrations, but prolonged supplementation should be avoided.

  4. Fabrication of multiwalled carbon nanotubes/polyaniline modified Au electrode for ascorbic acid determination.

    Science.gov (United States)

    Chauhan, Nidhi; Narang, Jagriti; Pundir, C S

    2011-05-07

    An ascorbate oxidase (AsOx) (E.C.1.10.3.3) purified from Lagenaria siceraria fruit was immobilized covalently onto a carboxylated multiwalled carbon nanotubes and polyaniline (c-MWCNT/PANI) layer electrochemically deposited on the surface of an Au electrode. The diffusion coefficient of ascorbic acid was determined as 3.05 × 10(-4) cm(2) s(-1). The behavior of different electrolytes on electro-deposition was also studied. An ascorbate biosensor was fabricated using a AsOx/c-MWCNT/PANI/Au electrode as a working electrode, Ag/AgCl (3 M/saturated KCl) as standard and Pt wire as an auxiliary electrode connected through a potentiostat. Linear range, response time and detection limit were 2-206 μM, 2 s and 0.9 μM respectively. The biosensor showed optimum response at pH 5.8 and in a broader temperature range (30-45 °C), when polarized at +0.6 V. The biosensor was employed for determination of ascorbic acid level in sera, fruit juices and vitamin C tablets. The sensor was evaluated with 91% recovery of added ascorbic acid in sera and 6.5% and 11.4% within and between batch coefficients of variation respectively for five serum samples. There was a good correlation (r = 0.98) between fruit juice ascorbic acid values by the standard 2,6-dichlorophenolindophenol (DCPIP) method and the present method. The enzyme electrode was used 200 times over a period of two months, when stored at 4 °C. The biosensor has advantages over earlier enzyme sensors in that it has no leakage of enzyme, due to the covalent coupling of enzyme with the support, lower response time, wider working range, higher storage stability and no interference by serum substances.

  5. Self-powered biosensor for ascorbic acid with a Prussian blue electrochromic display.

    Science.gov (United States)

    Zloczewska, Adrianna; Celebanska, Anna; Szot, Katarzyna; Tomaszewska, Dorota; Opallo, Marcin; Jönsson-Niedziolka, Martin

    2014-04-15

    We report on the development of a nanocarbon based anode for sensing of ascorbic acid (AA). The oxidation of AA on this anode occurs at a quite low overpotential which enables the anode to be connected to a biocathode to form an ascorbic acid/O2 biofuel cell that functions as a self-powered biosensor. In conjunction with a Prussian blue electrochromic display the anode can also work as a truly self-powered sensor. The oxidation of ascorbic acid at the anode leads to a reduction of the Prussian blue in the display. The reduced form of Prussian blue, called Prussian white, is transparent. The rate of change from blue to colourless is dependent on the concentration of ascorbic acid. The display can easily be regenerated by connecting it to the biocathode which returns the Prussian blue to its oxidized form. In this way we have created the first self-powered electrochromic sensor that gives quantitative information about the analyte concentration. This is demonstrated by measuring the concentration of ascorbic acid in orange juice. The reported quantitative read-out electrochromic display can serve as a template for the creation of cheap, miniturizable sensors for other relevant analytes.

  6. Fate of the synergistic antioxidant system ascorbic acid, lecithin, and tocopherol in mayonnaise : Partition of ascorbic acid

    DEFF Research Database (Denmark)

    Meyer, Anne S.; Jacobsen, Charlotte

    1996-01-01

    The distribution of ascorbic acid between the lipid and aqueous phase was investigated in mayonnaises enriched with fish oil containing a synergistic antioxidant mixture of ascorbic acid, lecithin and gamma-tocopherol, i.e., the A/L/T system (Loliger and Saucy 1989). The ascorbic acid was found...... to be located in the aqueous phase indicating that the A/L/T system broke down in mayonnaises. Based on the hypothesis that synergistic antioxidant action between ascorbic acid, lecithin and tocopherol requires that the three components are in close assembly, the results offer an explanation as to why the A...

  7. Fate of the synergistic antioxidant system ascorbic acid, lecithin, and tocopherol in mayonnaise : Partition of ascorbic acid

    DEFF Research Database (Denmark)

    Meyer, A.S.; Jacobsen, Charlotte Munch

    1996-01-01

    The distribution of ascorbic acid between the lipid and aqueous phase was investigated in mayonnaises enriched with fish oil containing a synergistic antioxidant mixture of ascorbic acid, lecithin and gamma-tocopherol, i.e., the A/L/T system (Loliger and Saucy 1989). The ascorbic acid was found...... to be located in the aqueous phase indicating that the A/L/T system broke down in mayonnaises. Based on the hypothesis that synergistic antioxidant action between ascorbic acid, lecithin and tocopherol requires that the three components are in close assembly, the results offer an explanation as to why the A...

  8. Vitamin C Content of Commercial Orange Juices

    Science.gov (United States)

    Haddad, Paul

    1977-01-01

    Describes an experiment designed to confirm that newly purchased commercial orange juice contains sufficient ascorbic acid to meet government standards, and to establish the rate of aerial oxidation of this ascorbic acid when the juice is stored in a refrigerator. (MLH)

  9. Slight Fermentation with Lactobacillus fermentium Improves the Taste (Sugar:Acid Ratio) of Citrus (Citrus reticulata cv. chachiensis) Juice.

    Science.gov (United States)

    Yu, Yuanshan; Xiao, Gengsheng; Xu, Yujuan; Wu, Jijun; Fu, Manqin; Wen, Jing

    2015-11-01

    The aim of this study was to evaluate the hypothesis that fermentation with Lactobacillus fermentium, which can metabolize citric acid, could be applied in improving the taste (sugar:acid ratio) of citrus juice. During fermentation, the strain of L. fermentium can preferentially utilize citric acid of citrus (Citrus reticulata cv. Chachiensis) juice to support the growth without the consumption of sugar. After 6 h of fermentation with L. fermentium at 30 °C, the sugar:acid ratio of citrus juice increased to 22:1 from 12:1, which resulted in that the hedonic scores of sweetness, acidity and overall acceptability of fermented-pasteurized citrus juice were higher than the unfermented-pasteurized citrus juice. Compared with unfermented-pasteurized citrus juice, the ORAC value and total amino acid showed a reduction, and no significant change (P > 0.05) in the L*, a*, b*, total soluble phenolics and ascorbic acid (Vc) content in the fermented-pasteurized citrus juice was observed as compared with unfermented-pasteurized citrus juice. Hence, slight fermentation with L. fermentium can be used for improving the taste (sugar:acid ratio) of citrus juice with the well retaining of quality.

  10. Influência da embalagem e estocagem no conteúdo de betacaroteno e ácido ascórbico em suco de manga “Ubá” industrializado = Influence of package and storage on the content of beta-carotene and ascorbic acid in industrialized “Ubá” mango juice

    Directory of Open Access Journals (Sweden)

    Daniela da Silva Oliveira

    2010-07-01

    Full Text Available Este trabalho investigou o conteudo e avaliou a estabilidade de doisantioxidantes naturais - β-caroteno e acido ascorbico (AA - em suco de manga "Uba" industrializado e armazenado em diferentes tempos de estocagem e correlacionou as recomendacoes de vitaminas A e C com o teor encontrado nos sucos. O β-caroteno e o AA foram analisados nos sucos comercializados em embalagem tetra pak, em cinco tempos de estocagem (1 a 5 meses e em embalagem de vidro, em tres tempos de estocagem (apos 3, 4 e 5 meses de armazenamento. A analise foi realizada por Cromatografia Liquida de Alta Eficiencia (CLAE. Nao foram detectadas diferencas estatisticamente significativas (α = 5% entre os diferentes tempos de estocagem, para ambos os componentes analisados, tanto em embalagens tetra pak quanto em embalagens de vidro. Alem disso, nao foram observadas diferencas significativas entre o conteudo de β-caroteno dos sucos comercializados nas duas embalagens. No entanto, houve diferenca significativa no teor de AA entre as diferentes embalagens, e a embalagem de vidro apresentou maior teor em relacao a embalagem tetrapak. Assim, as perdas ocasionadas especialmente pela permeabilidade da embalagem ao oxigenio deveriam ser alvo de atencao das industrias de alimentos.This work investigated the content and stability of two natural antioxidants . β-carotene and ascorbic acid (AA - in mango juice industrialized and stored during different storage times, correlating the recommendations of vitamins A and C with the content found in the juice. β-carotene and AA were analyzed in juice sold in tetra pak packaging, during five storage times (1 to 5months and in glass containers, during three storage times (after 3, 4 and 5 months of storage. The analysis was carried out using High Performance Liquid Chromatography (HPLC. No statically differences (α = 5 % were found between the different times of storage for both compounds analyzed, both in tetra pak package and glass container

  11. Radioprotective effects of ascorbic acid in barley seeds

    Energy Technology Data Exchange (ETDEWEB)

    Conger, B.V.

    1975-01-01

    Experiments were conducted to test the radioprotective effects of a naturally occurring reducing agent, ascorbic acid, on seeds (caryopses) of barley, Hordeum vulgare L. emend Lam. Seeds were soaked either before or after ..gamma.. or fission neutron irradiation in distilled water or ascorbic acid solutions ranging in concentration from 0.01 to 1.00 M. Results are reported as percentage germination, seedling height, seedling growth reduction, and (in one experiment) percent of cells with chromosome aberrations. As evidenced by both reduced germination and seedling growth, ascorbic acid was toxic when seeds were soaked for 1 hr at ambient temperature prior to irradiation and then planted immediately. When seeds were soaked in ascorbic acid before irradiation and soaked after irradiation in air-bubbled water at 0/sup 0/C for 18 hr, the toxicity disappeared, and a protective effect (which increased with increasing ascorbic acid concentration) was observed for ..gamma.. and, to a lesser extent, for neutron irradiation. Additional studies suggested that the protective effect was related to reduced hydration of the embryos of seeds soaked in ascorbic acid. Also, no radioprotective effect was observed when seeds were presoaked for 2 or 16 hr in 0.01 M ascorbic acid solutions buffered at pH 3 or pH 7. A protective effect was observed for seeds of 1.5 percent water content soaked after irradiation in an oxygen-bubbled ascorbic acid solution of 0.5 M but was not observed for seeds soaked in nitrogen-bubbled ascorbic acid. The protective effect against oxygen-dependent damage may be a result of interaction of ascorbic acid with radiation-induced free radicals.

  12. Absorption of folic acid and ascorbic acid from nutrient comparable beverages.

    Science.gov (United States)

    Carter, Brett; Monsivais, Pablo; Drewnowski, Adam

    2010-01-01

    One hundred percent fruit juices can help consumers increase the nutrient content of the diet since these beverages can be naturally rich in micronutrients. Micronutrient-fortified low-calorie beverages are an important alternative to those wishing to minimize their calorie intakes. However, little is known about the bioavailability of nutrients from fortified beverages relative to 100% fruit juices. The present study examined the bioavailability of ascorbic acid (AA) and folic acid (FA) in 100% orange juice (OJ) and a low-calorie beverage fortified with these nutrients. In a within-subjects, cross-over design, 12 adult men consumed a 591 mL serving of OJ, a low-calorie beverage fortified with AA and FA, and 1% low fat milk. Participants were aged 20 to 35 y, with body mass indexes between 20 and 30 kg/m(2). Blood plasma concentrations of AA and serum concentrations of FA were assayed by serial blood draws, made at 30 min intervals for 4.5 h. Blood plasma concentration of AA was significantly greater after ingestion of the fortified beverage compared to after OJ ingestion. However, the bioavailability of AA did not significantly differ from that of OJ. Analyses of FA indicated no significant difference between fortified beverage and OJ. Consumption of both vitamin containing beverages led to higher concentrations of AA and FA than the milk control. This study showed that similar levels of AA and FA bioavailability can be attained through ingestion of 100% OJ and a fortified beverage.

  13. Efeito do tratamento térmico na concentração de carotenóides, compostos fenólicos, ácido ascórbico e capacidade antioxidante do suco de tangerina murcote Effect of thermal treatment on the carotenoid, phenolic compound and ascorbic acid concentrations, and the antioxidant capacity of murcott tangerine juice

    Directory of Open Access Journals (Sweden)

    André de Souza Dutra

    2012-09-01

    possibilitaram menores alterações e/ou maiores retenções nos compostos determinados.This study evaluated the effect of thermal treatment on the total carotenoid concentration, the carotenoid profile (lutein, zeaxanthin, β-cryptoxanthin and β-carotene, total phenolic compound content, ascorbic acid content and antioxidant capacity of Murcott Tangerine juice. Using a tubular heat exchanger eleven treatments were evaluated based on a full 2² factorial design with three replicates at the central point, four axial points and a region of observation from 88 to 100 ºC and from 16 to 44 s. The total carotenoid content decreased significantly in almost all treatments when compared with the results obtained for the fresh juice. The carotenoid levels (lutein, zeaxanthin and β-cryptoxanthin were not significantly reduced by most of the treatments studied, and the β-carotene content was not significantly changed by any treatment. For the carotenoid contents, the analysis of variance showed no significant interactions between the variables of temperature and time. The levels of ascorbic acid and total phenolic compounds decreased in six of the conditions evaluated, while in four treatments an increase in the total phenolic compounds was observed, probably due to evaporation of water from the juice. The greatest reduction and the greatest increase of, respectively, ascorbic acid and total phenolic compounds were observed for the binomial of 100 ºC/30 s. The ascorbic acid content was significantly influenced by the temperature, and its degradation process can be described using a quadratic model. All the treatments applied reduced the antioxidant capacity of the juice, but the reduction was higher for the binomial 100 ºC/30 s. The nutritional characteristics of the juice were little affected by the changes observed, and the heat treatments carried out at 94 ºC for 16 to 44 s allowed for the smallest changes and/or the highest retentions of the determined compounds.

  14. Synthesis of New L-Ascorbic Ferulic Acid Hybrids

    Directory of Open Access Journals (Sweden)

    Sylvain Rault

    2007-11-01

    Full Text Available A feasibility and chemical study of the coupling conditions of L-ascorbic acidwith ferulic acid derivatives are described on the basis of the known synergistic effects ofmixtures of various antioxidants. Novel L-ascorbic ferulic hybrids linked at the C-3hydroxyl group were prepared with the aim to protect the alcohol function and the enediolsystem.

  15. Ascorbic acid does not influence consciousness recovery after anesthesia.

    Science.gov (United States)

    Talley V, Henry C; Wicks, Mona N; Carter, Michael; Roper, Brad

    2009-01-01

    Several studies have examined the influence of general anesthesia on changes in consciousness and unconscious cognitive processes. However, much remains to be learned about potential moderators of general anesthetic agents, such as antioxidants including ascorbic acid, and their influence on the recovery of consciousness following general anesthesia. General anesthesia potentially affects plasma ascorbic acid levels and may impair consciousness during the postoperative period; however, published literature regarding these relationships is equivocal. Ascorbic acid is important for brain function and may be related to the return of postoperative consciousness through action on the synaptic receptors in the brain. This study was designed as a pretest-posttest repeated measures investigation. Ascorbic acid levels were measured at four time periods in patients (N = 50) undergoing surgery and general anesthesia. Following surgery, patients were administered a paper-and-pencil measure of concentration that served as an index of post-anesthesia consciousness. The results suggest that changes occur in plasma ascorbic acid levels at different time points during the anesthesia regimen in nonemergent surgical patients. No statistically significant relationships were found between plasma ascorbic acid levels and improved post-anesthesia consciousness, suggesting that ascorbic acid does not influence recovery of consciousness following general anesthesia.

  16. A theoretical study on ascorbic acid dissociation in water clusters.

    Science.gov (United States)

    Demianenko, Eugeniy; Ilchenko, Mykola; Grebenyuk, Anatoliy; Lobanov, Victor; Tsendra, Oksana

    2014-03-01

    Dissociation of ascorbic acid in water has been studied by using a cluster model. It was examined by density functional theory (DFT) with the В3LYP, M06, and wB97XD functionals and a 6-311++G(d,p) basis set. The thermodynamic and kinetic characteristics of proton transfer from ascorbic acid molecule to water clusters were calculated as well as the equilibrium constants (pK a ) for the related processes. The used functionals in the DFT method together with continuum solvent models provided results close to the experimental data for the dissociation constant of ascorbic acid in aqueous solution.

  17. Radiation protection by ascorbic acid in sodium alginate solutions

    Energy Technology Data Exchange (ETDEWEB)

    Aliste, A.J.; Mastro, N.L. Del [Center of Radiation Technology, IPEN/CNEN/SP, University City, 05508-000 Sao Paulo (Brazil)]. E-mail: ajaliste@ipen.br

    2004-07-01

    Alginates are gelling hydrocolloids extracted from brown seaweed used widely in the nourishing and pharmaceutical industries. As alginic acid gellification retard food entrance in the stomach alginate is an additive used in diets. The objective of this work was to study the protective action of the ascorbic acid in alginate solutions against the action of {sup 60} Co gamma radiation. One % (w/v) solutions of alginate had been used and concentrations of ascorbic acid varied from 0 to 2.5% (w/v). The solutions were irradiated with doses up to 10 kGy. Viscosity/dose relationship and the p H of the solutions at 25 Centigrade were determined. Ascorbic acid behaved as an antioxidant against radiation oxidative shock in this model system of an irradiated viscous solution. Besides its radiation protective role on alginate solutions ascorbic acid promoted a viscosity increase in the range of concentrations employed. (Author)

  18. Carbon Dot Based Sensing of Dopamine and Ascorbic Acid

    Directory of Open Access Journals (Sweden)

    Upama Baruah

    2014-01-01

    Full Text Available We demonstrate carbon dot based sensor of catecholamine, namely, dopamine and ascorbic acid. Carbon dots (CDs were prepared from a green source: commercially available Assam tea. The carbon dots prepared from tea had particle sizes of ∼0.8 nm and are fluorescent. Fluorescence of the carbon dots was found to be quenched in the presence of dopamine and ascorbic acid with greater sensitivity for dopamine. The minimum detectable limits were determined to be 33 μM and 98 μM for dopamine and ascorbic acid, respectively. The quenching constants determined from Stern-Volmer plot were determined to be 5 × 10−4 and 1 × 10−4 for dopamine and ascorbic acid, respectively. A probable mechanism of quenching has been discussed in the paper.

  19. Ascorbic Acid Efflux from Human Brain Microvascular Pericytes: Role of Re-uptake

    OpenAIRE

    May, James M.; Qu, Zhi-chao

    2015-01-01

    Microvascular pericytes take up ascorbic acid on the ascorbate transporter SVCT2. Intracellular ascorbate then protects the cells against apoptosis induced by culture at diabetic glucose concentrations. To investigate whether pericytes might also provide ascorbate to the underlying endothelial cells, we studied ascorbate efflux from human pericytes. When loaded with ascorbate to intracellular concentrations of 0.8–1.0 mM, almost two-thirds of intracellular ascorbate effluxed from the cells ov...

  20. Influence of orange cultivar and mandarin postharvest storage on polyphenols, ascorbic acid and antioxidant activity during gastrointestinal digestion.

    Science.gov (United States)

    De Ancos, Begoña; Cilla, Antonio; Barberá, Reyes; Sánchez-Moreno, Concepción; Cano, M Pilar

    2017-06-15

    Polyphenols, ascorbic acid content and antioxidant activity of two sweet oranges (Navel-N and Cara Cara-CC) and mandarin (Clementine-M) as well as their bioaccessibilities were evaluated in pulps and compared to those in fresh juice. Thus, pulps of oranges and mandarins displayed higher hesperidin (HES), narirutin (NAR), total flavonoids (TF), total phenols (TP) and antioxidant activity (AAC) than their corresponding juices. Also, CC products presented higher bioactive compounds content than N ones. Bioaccessibility of bioactive compounds and AAC were higher in pulps of both oranges and mandarin than in their corresponding juices. Oranges (N and CC) pulps and juices presented higher bioaccessibilities than mandarin ones. The postharvest storage of mandarin at 12°C during 5weeks not only produced a significant increase of the bioactive compounds but also an increase of their bioaccessibility. The bioaccessibility of Citrus bioactive compounds is necessary for calculating more accurately their daily intake amount.

  1. Macrokinetics of magnesium sulfite oxidation inhibited by ascorbic acid

    Energy Technology Data Exchange (ETDEWEB)

    Lidong, Wang, E-mail: wld@tsinghua.edu.cn [School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003 (China); Department of Environmental Science and Engineering, Tsinghua University, Beijing 100054 (China); Yongliang, Ma, E-mail: liang@tsinghua.edu.cn [Department of Environmental Science and Engineering, Tsinghua University, Beijing 100054 (China); Wendi, Zhang; Qiangwei, Li; Yi, Zhao [School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003 (China); Zhanchao, Zhang [Jinan Environmental Monitoring Center, Jinan 250014 (China)

    2013-08-15

    Graphical abstract: Ascorbic acid is used as an inhibitor to retard the oxidation rate of magnesium sulfite. It shows that the oxidation rate would decrease greatly with the rise of initial ascorbic acid concentration, which provides a useful reference for sulfite recovery in magnesia desulfurization. -- Highlights: • We studied the kinetics of magnesium sulfite oxidation inhibited by ascorbic acid. • The oxidation process was simulated by a three-phase model and proved by HPLC–MS. • We calculated the kinetic parameters of intrinsic oxidation of magnesium sulfite. -- Abstract: Magnesia flue gas desulfurization is a promising process for small to medium scale industrial coal-fired boilers in order to reduce sulfur dioxide emissions, in which oxidation control of magnesium sulfite is of great importance for the recycling of products. Effects of four inhibitors were compared by kinetic experiments indicating that ascorbic acid is the best additive, which retards the oxidation process of magnesium sulfite in trace presence. The macrokinetics of magnesium sulfite oxidation inhibited by ascorbic acid were studied. Effects of the factors, including ascorbic acid concentration, magnesium sulfite concentration, oxygen partial pressure, pH, and temperature, were investigated in a stirred reactor with bubbling. The results show that the reaction rate is −0.55 order in ascorbic acid, 0.77 in oxygen partial pressure, and zero in magnesium sulfite concentration, respectively. The apparent activation energy is 88.0 kJ mol{sup −1}. Integrated with the kinetic model, it is concluded that the oxidation rate of magnesium sulfite inhibited by ascorbic acid is controlled by the intrinsic chemical reaction. The result provides a useful reference for sulfite recovery in magnesia desulfurization.

  2. Ascorbic acid: Nonradioactive extracellular space marker in canine heart

    Energy Technology Data Exchange (ETDEWEB)

    Reil, G.H.; Frombach, R.; Kownatzki, R.; Quante, W.; Lichtlen, P.R. (Medizinische Hochschule Hannover (West Germany))

    1987-11-01

    The distribution pattern of ascorbic acid and L-({sup 14}C)ascorbic acid in myocardial tissue was compared with those of the classical radioactive extracellular space markers ({sup 3}H)-inulin, ({sup 3}H)sucrose, and Na{sup 82}Br. A new polarographic techniques was developed for analogue registration of ascorbic acid concentration in coronary venous blood. The kinetic data of the markers were studied in an open-chest canine heart preparation during a constant tracer infusion of up to 9 min. Distribution volumes were calculated based on the mean transit time method of Zierler. The distribution volume of ascorbic acid as well as of L-({sup 14}C)ascorbic acid in myocardial tissue agreed closely with those of ({sup 3}H)inulin and ({sup 3}H)sucrose as well as {sup 82}Br. The obtained kinetic data confirmed that ascorbic acid exhibits the physicochemical properties of an extracellular space marker, though this compound was shown to leak slowly into myocardial cells. Favorable attributes of this indicator are its low molecular weight, high diffusibility in interstitial fluid, low binding affinity to macromolecules, and high transcapillary as well as low transplasmalemmal penetration rate. Therefore, this nonradioactive marker can be applied in a safe and simple fashion, and without untoward side effects in experimental animals as well as in patients.

  3. L-Ascorbic Acid: A Multifunctional Molecule Supporting Plant Growth and Development

    OpenAIRE

    2013-01-01

    L-Ascorbic acid (vitamin C) is as essential to plants as it is to animals. Ascorbic acid functions as a major redox buffer and as a cofactor for enzymes involved in regulating photosynthesis, hormone biosynthesis, and regenerating other antioxidants. Ascorbic acid regulates cell division and growth and is involved in signal transduction. In contrast to the single pathway responsible for ascorbic acid biosynthesis in animals, plants use multiple pathways to synthesize ascorbic acid, perhaps re...

  4. PLASMID DNA DAMAGE CAUSED BY METHYLATED ARSENICALS, ASCORBIC ACID AND HUMAN LIVER FERRITIN

    Science.gov (United States)

    PLASMID DNA DAMAGE CAOUSED BY METHYLATED ARSENICALS, ASCORBIC ACID AND HUMAN LIVER FERRITINABSTRACT Both dimethylarsinic acid (DMA(V)) and dimethylarsinous acid (DMA(III)) release iron from human liver ferritin (HLF) with or without the presence of ascorbic acid. ...

  5. Ascorbate and dehydroascorbic acid as reliable biomarkers of oxidative stress

    DEFF Research Database (Denmark)

    Lykkesfeldt, Jens

    2007-01-01

    , the analytical reproducibility was tested by repeated analysis of plasma aliquots from one individual over four years. The plasma was subjected to acidic deproteinization with an equal volume of 10% meta-phosphoric acid containing 2 mM EDTA and analyzed for ascorbate and dehydroascorbic acid by high...

  6. Low brain ascorbic acid increases susceptibility to seizures in mouse models of decreased brain ascorbic acid transport and Alzheimer's disease.

    Science.gov (United States)

    Warner, Timothy A; Kang, Jing-Qiong; Kennard, John A; Harrison, Fiona E

    2015-02-01

    Seizures are a known co-occurring symptom of Alzheimer's disease, and they can accelerate cognitive and neuropathological dysfunction. Sub-optimal vitamin C (ascorbic acid) deficiency, that is low levels that do not lead the sufferer to present with clinical signs of scurvy (e.g. lethargy, hemorrhage, hyperkeratosis), are easily obtainable with insufficient dietary intake, and may contribute to the oxidative stress environment of both Alzheimer's disease and epilepsy. The purpose of this study was to test whether mice that have diminished brain ascorbic acid in addition to carrying human Alzheimer's disease mutations in the amyloid precursor protein (APP) and presenilin 1 (PSEN1) genes, had altered electrical activity in the brain (electroencephalography; EEG), and were more susceptible to pharmacologically induced seizures. Brain ascorbic acid was decreased in APP/PSEN1 mice by crossing them with sodium vitamin C transporter 2 (SVCT2) heterozygous knockout mice. These mice have an approximately 30% decrease in brain ascorbic acid due to lower levels of SVCT2 that supplies the brain with ASC. SVCT2+/-APP/PSEN1 mice had decreased ascorbic acid and increased oxidative stress in brain, increased mortality, faster seizure onset latency following treatment with kainic acid (10 mg/kg i.p.), and more ictal events following pentylenetetrazol (50 mg/kg i.p.) treatment. Furthermore, we report the entirely novel phenomenon that ascorbic acid deficiency alone increased the severity of kainic acid- and pentylenetetrazol-induced seizures. These data suggest that avoiding ascorbic acid deficiency may be particularly important in populations at increased risk for epilepsy and seizures, such as Alzheimer's disease.

  7. Ascorbic Acid Contents in Chili Peppers (Capsicum L.

    Directory of Open Access Journals (Sweden)

    Owk ANIEL KUMAR

    2009-12-01

    Full Text Available The genus Capsicum commonly known as chili pepper is a major spice crop and is almost cosmopolitan in distribution. The nutritive value of chili pepper is largely determined by ascorbic acid content. The fruits at five ripening stages viz., (M1, M2, M3, M4 and M5 from seventeen cultivars of Capsicum annuum L and one cultivar of Capsicum frutescens L were analyzed for ascorbic acid content. Among eighteen genotypes the C. annuum var. IC: 119262(CA2 showed higher ascorbic acid content (mg/100g FW i.e., 208.0�0.68 (M1, 231.0�0.66 (M2, 280.0�0.31 (M3, 253.0�0.34 (M4 and 173.7�0.27 (M5. The study revealed that the gradual increase in ascorbic acid content from green to red and subsequently declined in the lateral stages (red partially dried and red fully dried fruits. The variability of ascorbic acid content in the genotypes suggests that these selected genotypes may be use full as parents in hybridization programs to produce fruits with good nutritional values.

  8. Ascorbic Acid Contents in Chili Peppers (Capsicum L.

    Directory of Open Access Journals (Sweden)

    Owk ANIEL KUMAR

    2009-12-01

    Full Text Available The genus Capsicum commonly known as chili pepper is a major spice crop and is almost cosmopolitan in distribution. The nutritive value of chili pepper is largely determined by ascorbic acid content. The fruits at five ripening stages viz., (M1, M2, M3, M4 and M5 from seventeen cultivars of Capsicum annuum L and one cultivar of Capsicum frutescens L were analyzed for ascorbic acid content. Among eighteen genotypes the C. annuum var. IC: 119262(CA2 showed higher ascorbic acid content (mg/100g FW i.e., 208.00.68 (M1, 231.00.66 (M2, 280.00.31 (M3, 253.00.34 (M4 and 173.70.27 (M5. The study revealed that the gradual increase in ascorbic acid content from green to red and subsequently declined in the lateral stages (red partially dried and red fully dried fruits. The variability of ascorbic acid content in the genotypes suggests that these selected genotypes may be use full as parents in hybridization programs to produce fruits with good nutritional values.

  9. Protective effects of ascorbic acid and garlic extract against lead-induced apoptosis in developing rat hippocampus.

    Science.gov (United States)

    Ebrahimzadeh-Bideskan, Ali-Reza; Hami, Javad; Alipour, Fatemeh; Haghir, Hossein; Fazel, Ali-Reza; Sadeghi, Akram

    2016-10-01

    Lead exposure has negative effects on developing nervous system and induces apoptosis in newly generated neurons. Natural antioxidants (i.e. Ascorbic acid and Garlic) might protect against lead-induced neuronal cell damage. The aim of the present study was to investigate the protective effects of Ascorbic acid and Garlic administration during pregnancy and lactation on lead-induced apoptosis in rat developing hippocampus. Timed pregnant Wistar rats were administrated with Lead (1500 ppm) via drinking water (Pb group) or lead plus Ascorbic acid (Pb + AA Group, 500 mg/kg, IP), or lead plus Garlic Extract (Pb + G Group, 1 ml garlic juice/100 g BW, via Gavage) from early gestation (GD 0) until postnatal day 50 (PN 50). At the end of experiments, the pups' brains were carefully dissected. To identify neuronal death, the brain sections were stained with TUNEL assay. Mean of blood and brain lead levels increased significantly in Pb group comparing to other studied groups (P Ascorbic acid or Garlic (P Ascorbic acid and Garlic during pregnancy and lactation protect against lead-induced neuronal cell apoptosis in the hippocampus of rat pups partially via the reduction of Pb concentration in the blood and in the brain.

  10. Comparison of bioactive components in fresh, pressurized, pasteurized and sterilized pennywort (Centella asiatica L.) juices

    Science.gov (United States)

    Apichartsrangkoon, Arunee; Chattong, Utaiwan; Chunthanom, Pornprapa

    2012-06-01

    The biologically active constituents of pennywort juice were analyzed by HPLC. The juice extract contained the bioactive glycosides, including asiaticoside and madecassoside. Antioxidant properties of juices were determined in terms of ferric-reducing antioxidant power assay, total polyphenol, β-carotene and ascorbic acid contents. After processing, asiaticoside, madecassoside and β-carotene in the extracted juice were relatively stable with no significant losses occurring. Pressurization could significantly retain ascorbic acid, polyphenols and antioxidant capacity than those pasteurization or sterilization. For storage assessment, asiaticoside in the processed juices was relatively stable during 4 months storage. Losses of ascorbic acid in the pressurized juice during storage were greater than in pasteurized and sterilized juice. However, the total amount of ascorbic acid retained in pressurized juice was still higher than those thermal-treated products.

  11. The cytochemical localization of ascorbic acid in root tip cells.

    Science.gov (United States)

    JENSEN, W A; KAVALJIAN, L G

    1956-01-25

    The intracellular distribution of ascorbic acid was studied in frozen-dried root tips of Allium cepa and Vicia faba by the silver nitrate procedure. The sites of the ascorbic acid as indicated by the deposited silver appear as spherical (0.2 to 0.6 micro in diameter) cytoplasmic particles. The site appears to have small amounts of lipides and to be rich in ribonucleic acid. These particles are concluded to be submicroscopic in size and associated, in the elongating cell, with the cell surface. In the meristematic cells they appear fewer in number and are distributed throughout the cytoplasm.

  12. Ascorbic acid metabolism during sweet cherry (Prunus avium) fruit development.

    Science.gov (United States)

    Liang, Dong; Zhu, Tingting; Ni, Zhiyou; Lin, Lijin; Tang, Yi; Wang, Zhihui; Wang, Xun; Wang, Jin; Lv, Xiulan; Xia, Hui

    2017-01-01

    To elucidate metabolism of ascorbic acid (AsA) in sweet cherry fruit (Prunus avium 'Hongdeng'), we quantified AsA concentration, cloned sequences involved in AsA metabolism and investigated their mRNA expression levels, and determined the activity levels of selected enzymes during fruit development and maturation. We found that AsA concentration was highest at the petal-fall period (0 days after anthesis) and decreased progressively during ripening, but with a slight increase at maturity. AsA did nevertheless continue to accumulate over time because of the increase in fruit fresh weight. Full-length cDNAs of 10 genes involved in the L-galactose pathway of AsA biosynthesis and 10 involved in recycling were obtained. Gene expression patterns of GDP-L-galactose phosphorylase (GGP2), L-galactono-1, 4-lactone dehydrogenase (GalLDH), ascorbate peroxidase (APX3), ascorbate oxidase (AO2), glutathione reductase (GR1), and dehydroascorbate reductase (DHAR1) were in accordance with the AsA concentration pattern during fruit development, indicating that genes involved in ascorbic acid biosynthesis, degradation, and recycling worked in concert to regulate ascorbic acid accumulation in sweet cherry fruit.

  13. Ascorbate and dehydroascorbic acid as reliable biomarkers of oxidative stress

    DEFF Research Database (Denmark)

    Lykkesfeldt, Jens

    2007-01-01

    Lack of post-sampling stability of ascorbate and dehydroascorbic acid and failure to block their in vivo equilibrium have lowered their value as biomarkers of oxidative stress and limited the ability to further investigate their possible role in disease prevention. In the present paper, the analy......Lack of post-sampling stability of ascorbate and dehydroascorbic acid and failure to block their in vivo equilibrium have lowered their value as biomarkers of oxidative stress and limited the ability to further investigate their possible role in disease prevention. In the present paper......, the analytical reproducibility was tested by repeated analysis of plasma aliquots from one individual over four years. The plasma was subjected to acidic deproteinization with an equal volume of 10% meta-phosphoric acid containing 2 mM EDTA and analyzed for ascorbate and dehydroascorbic acid by high......-performance liquid chromatography with coulometric detection. In a parallel experiment, stability of human plasma samples treated as above and stored at -80°C for five years was tested in a cohort of 131 individuals. No degradation or shift in the equilibrium between ascorbate and dehydroascorbic acid was observed...

  14. Glassy carbon electrodes modified with multiwalled carbon nanotubes for the determination of ascorbic acid by square-wave voltammetry

    Directory of Open Access Journals (Sweden)

    Sushil Kumar

    2012-05-01

    Full Text Available Multiwalled carbon nanotubes were used to modify the surface of a glassy carbon electrode to enhance its electroactivity. Nafion served to immobilise the carbon nanotubes on the electrode surface. The modified electrode was used to develop an analytical method for the analysis of ascorbic acid (AA by square-wave voltammetry (SWV. The oxidation of ascorbic acid at the modified glassy carbon electrode showed a peak potential at 315 mV, about 80 mV lower than that observed at the bare (unmodified electrode. The peak current was about threefold higher than the response at the bare electrode. Replicate measurements of peak currents showed good precision (3% rsd. Peak currents increased with increasing ascorbic acid concentration (dynamic range = 0.0047–5.0 mmol/L and displayed good linearity (R2 = 0.994. The limit of detection was 1.4 μmol/L AA, while the limit of quantitation was 4.7 μmol/L AA. The modified electrode was applied to the determination of the amount of ascorbic acid in four brands of commercial orange-juice products. The measured content agreed well (96–104% with the product label claim for all brands tested. Recovery tests on spiked samples of orange juice showed good recovery (99–104%. The reliability of the SWV method was validated by conducting parallel experiments based on high-performance liquid chromatography (HPLC with absorbance detection. The observed mean AA contents of the commercial orange juice samples obtained by the two methods were compared statistically and were found to have no significant difference (P = 0.05.

  15. High dose of ascorbic acid induces cell death in mesothelioma cells.

    Science.gov (United States)

    Takemura, Yukitoshi; Satoh, Motohiko; Satoh, Kiyotoshi; Hamada, Hironobu; Sekido, Yoshitaka; Kubota, Shunichiro

    2010-04-02

    Malignant mesothelioma is an asbestos-related fatal disease with no effective cure. Recently, high dose of ascorbate in cancer treatment has been reexamined. We studied whether high dose of ascorbic acid induced cell death of four human mesothelioma cell lines. High dose of ascorbic acid induced cell death of all mesothelioma cell lines in a dose-dependent manner. We further clarified the cell killing mechanism that ascorbic acid induced reactive oxygen species and impaired mitochondrial membrane potential. In vivo experiment, intravenous administration of ascorbic acid significantly decreased the growth rate of mesothelioma tumor inoculated in mice. These data suggest that ascorbic acid may have benefits for patients with mesothelioma.

  16. ANTIOXIDANT AND PRO-OXIDANT EFFECT OF ASCORBIC ACID

    Directory of Open Access Journals (Sweden)

    Goran Rankovic

    2005-01-01

    Full Text Available Free radicals attack proteins, lipids, enzymes and DNA causing pathological changes in organism. There are many mechanisms that organism uses to fight against free radicals. Ascorbic acid is one of the strongest reducers and eliminators of free radicals. It reduces stable oxygenic, azoth and thyol radicals and acts as a primary defense against water radicals in blood. When radicals are dissolved in water suspensions of erythrocytes and low density lipoproteins (LDL, ascorbic acid catches and eliminates free radicals before they arrive to the membrane and LDL molecules. Even though ascorbic acid is not capable of eliminating free radicals out of fluid medium, it acts as synergist to alpha-tocopherol in lipid section, contributes to the lessening of lipid tocoperoxil radicals, and above all, regenerates alpha-tocopherol. Ascorbic acid may act as pro-oxidant under in vitro conditions in the presence of metals; however, this effect is probably not important under in vivo conditions where metal ions, being sequestered, become second reducers.

  17. Methylene Blue-Ascorbic Acid: An Undergraduate Experiment in Kinetics.

    Science.gov (United States)

    Snehalatha, K. C.; And Others

    1997-01-01

    Describes a laboratory exercise involving methylene blue and L-ascorbic acid in a simple clock reaction technique to illustrate the basic concepts of chemical kinetics. If stock solutions are supplied and each type of experiment takes no more than half an hour, the entire investigation can be completed in three practical sessions of three hours…

  18. Methylene Blue-Ascorbic Acid: An Undergraduate Experiment in Kinetics.

    Science.gov (United States)

    Snehalatha, K. C.; And Others

    1997-01-01

    Describes a laboratory exercise involving methylene blue and L-ascorbic acid in a simple clock reaction technique to illustrate the basic concepts of chemical kinetics. If stock solutions are supplied and each type of experiment takes no more than half an hour, the entire investigation can be completed in three practical sessions of three hours…

  19. Chromium-induced membrane damage: protective role of ascorbic acid

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Importance of chromium as environmental toxicant is largely due to impact on the body to produce cellular toxicity. The impact of chromium and their supplementation with ascorbic acid was studied on plasma membrane of liver and kidney in male Wistar rats (80 - 100gbody weight). It has been observed that the intoxication with chromium ( i. p. ) at the dose of 0.8 mg/100g body weight per day for a period of 28 days causes significant increase in the level of cholesterol and decrease in the level of phospbolipid of both liver and kidney. The alkaline pbosphatase, total ATPase and Na + -K + -ATPase activities were significantly decreased in both liver and kidney after chromium treatment,except total ATPase activity of kidney. It is suggested that chromium exposure at the present dose and duration induce for the alterations of structure and function of both liver and kidney plasma membrane. Ascorbic acid ( i.p. at the dose of 0.5 mg,/100g body weight per day for period of 28 days) supplementation can reduce these structural changes in the plasma membrane of liver and kidney. But the functional changes can not be completely replenished by the ascorbic acid supplementation in response to chromium exposure. So it is also suggested that ascorbic acid (nutritional antioxidant) is useful free radical scavenger to restrain the chromium-induced membrane damage.

  20. Ascorbic acid for the healing of skin wounds in rats

    Directory of Open Access Journals (Sweden)

    CC. Lima

    Full Text Available BACKGROUND: Healing is a complex process that involves cellular and biochemical events. Several medicines have been used in order to shorten healing time and avoid aesthetic damage. OBJECTIVE: to verify the topical effect of ascorbic acid for the healing of rats' skin wounds through the number of macrophages, new vessels and fibroblast verifications in the experimental period; and analyse the thickness and the collagen fibre organization in the injured tissue. METHODS: Male Rattus norvegicus weighing 270 ± 30 g were used. After thionembutal anesthesia, 15 mm transversal incisions were made in the animals' cervical backs. They were divided into two groups: Control Group (CG, n = 12 - skin wound cleaned with water and soap daily; Treated Group (TG, n = 12 - skin wound cleaned daily and treated with ascorbic acid cream (10%. Samples of skin were collected on the 3rd, 7th and 14th days. The sections were stained with hematoxylin-eosin and picrosirius red for morphologic analysis. The images were obtained and analysed by a Digital Analyser System. RESULTS: The ascorbic acid acted on every stage of the healing process. It reduced the number of macrophages, increased the proliferation of fibroblasts and new vessels, and stimulated the synthesis of thicker and more organized collagen fibres in the wounds when compared to CG. CONCLUSION: Ascorbic acid was shown to have anti-inflammatory and healing effects, guaranteeing a suiTable environment and conditions for faster skin repair.

  1. ASCORBIC ACID IS DECREASED IN INDUCED SPUTUM OF MILD ASTHMATICS

    Science.gov (United States)

    Asthma is primarily an airways inflammatory disease, and the bronchial airways have been shown to be particularly susceptible to oxidant-induced tissue damage. The antioxidant ascorbic acid (AA) plays an essential role in defending against oxidant attack in the airways. Decreased...

  2. An Inquiry into the Effect of Heating on Ascorbic Acid

    Science.gov (United States)

    Yip, Din Yan

    2009-01-01

    Investigations that study the effect of heating on ascorbic acid are commonly performed in schools, but the conclusions obtained are quite variable and controversial. Some results indicate that heating may destroy vitamin C, but others suggest that heating may have no effect. This article reports an attempt to resolve this confusion through a…

  3. 21 CFR 862.1095 - Ascorbic acid test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ascorbic acid test system. 862.1095 Section 862.1095 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  4. Response of antioxidant system of tomato to water deficit stress and its interaction with ascorbic acid

    Directory of Open Access Journals (Sweden)

    Fatemeh Daneshmand

    2014-03-01

    Full Text Available Environmental stresses including water deficit stress may produce oxidants such as reactive oxygen species that damage the membrane structure in plants. Among the antioxidants, ascorbic acid has a critical role in the cell and scavenges reactive oxygen species. In this research, effects of ascorbic acid at two levels (0 and 10 mM and water deficit stress based on 3 levels of field capacity (100, 60 and 30% were studied in tomato plants. Both levels of stress increased lipid peroxidation, reduced the amount of ascorbic acid and glutathione and increased the activity of enzymes superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase, guaiacol peroxidase and reduced the growth parameters. Ascorbic acid treatment, reduced lipid peroxidation, increased ascorbic acid and glutathione levels and decreased the activity of superoxide dismutase, catalase, ascorbate peroxidase, glutathione peroxidase and guaiacol peroxidase and positive effects of ascorbic acid treatment appeared to improve the plant growth parameters.

  5. Control of enzymatic browning in apple slices by using ascorbic acid under different conditions.

    Science.gov (United States)

    el-Shimi, N M

    1993-01-01

    Control of phenol oxidase activity in apple slices by the use of ascorbic acid at different pH values, temperature and time of incubation was investigated. The enzyme was almost inactivated at 1% and 1.5% ascorbic acid. Ascorbic acid solution (1%) caused a remarkable inhibition with the increasing acidity up to pH = 1. Heating treatments for apple slices dipped in 1% ascorbic acid caused a reduction of enzymatic browning, optimum temperature for inactivation of the enzyme was between 60-70 degrees C for 15 minutes. Increasing the time of dipping apple slices in 1% ascorbic acid solutions and at different pH values reduce phenolase activity.

  6. The vitamin C content of orange juice packed in an oxygen scavenger material

    NARCIS (Netherlands)

    Zerdin, K.; Rooney, M.L.; Vermuë, J.

    2003-01-01

    A storage study of orange juice packed in oxygen scavenging (OS) film and oxygen barrier film was conducted to determine the extent of ascorbic acid loss due to oxygen as a function of time and temperature. The initial concentration of ascorbic acid in the orange juice was 374 mg/l and this was foun

  7. The vitamin C content of orange juice packed in an oxygen scavenger material

    NARCIS (Netherlands)

    Zerdin, K.; Rooney, M.L.; Vermuë, J.

    2003-01-01

    A storage study of orange juice packed in oxygen scavenging (OS) film and oxygen barrier film was conducted to determine the extent of ascorbic acid loss due to oxygen as a function of time and temperature. The initial concentration of ascorbic acid in the orange juice was 374 mg/l and this was

  8. Influência da embalagem e estocagem no conteúdo de beta-caroteno e ácido ascórbico em suco de manga “Ubá” industrializado - doi: 10.4025/actascihealthsci.v32i2.6178 Influence of package and storage on the content of beta-carotene and ascorbic acid in industrialized “Ubá” mango juice - doi: 10.4025/actascihealthsci.v32i2.6178

    Directory of Open Access Journals (Sweden)

    Sônia Machado Rocha Ribeiro

    2010-09-01

    Full Text Available Este trabalho investigou o conteúdo e avaliou a estabilidade de dois antioxidantes naturais - β-caroteno e ácido ascórbico (AA - em suco de manga “Ubá” industrializado e armazenado em diferentes tempos de estocagem e correlacionou as recomendações de vitaminas A e C com o teor encontrado nos sucos. O β-caroteno e o AA foram analisados nos sucos comercializados em embalagem tetra pak, em cinco tempos de estocagem (1 a 5 meses e em embalagem de vidro, em três tempos de estocagem (após 3, 4 e 5 meses de armazenamento. A análise foi realizada por Cromatografia Líquida de Alta Eficiência (CLAE. Não foram detectadas diferenças estatisticamente significativas (α = 5% entre os diferentes tempos de estocagem, para ambos os componentes analisados, tanto em embalagens tetra pak quanto em embalagens de vidro. Além disso, não foram observadas diferenças significativas entre o conteúdo de β-caroteno dos sucos comercializados nas duas embalagens. No entanto, houve diferença significativa no teor de AA entre as diferentes embalagens, e a embalagem de vidro apresentou maior teor em relação à embalagem tetra pak. Assim, as perdas ocasionadas especialmente pela permeabilidade da embalagem ao oxigênio deveriam ser alvo de atenção das indústrias de alimentos.This work investigated the content and stability of two natural antioxidants – β-carotene and ascorbic acid (AA – in mango juice industrialized and stored during different storage times, correlating the recommendations of vitamins A and C with the content found in the juice. β-carotene and AA were analyzed in juice sold in tetra pak packaging, during five storage times (1 to 5 months and in glass containers, during three storage times (after 3, 4 and 5 months of storage. The analysis was carried out using High Performance Liquid Chromatography (HPLC. No statically differences (α = 5 % were found between the different times of storage for both compounds analyzed, both in

  9. Performance of structured lipids incorporating selected phenolic and ascorbic acids.

    Science.gov (United States)

    Gruczynska, Eliza; Przybylski, Roman; Aladedunye, Felix

    2015-04-15

    Conditions applied during frying require antioxidant which is stable at these conditions and provides protection for frying oil and fried food. Novel structured lipids containing nutraceuticals and antioxidants were formed by enzymatic transesterification, exploring canola oil and naturally occurring antioxidants such as ascorbic and selected phenolic acids as substrates. Lipozyme RM IM lipase from Rhizomucor miehei was used as biocatalyst. Frying performance and oxidative stability of the final transesterification products were evaluated. The novel lipids showed significantly improved frying performance compared to canola oil. Oxidative stability assessment of the structured lipids showed significant improvement in resistance to oxidative deterioration compared to original canola oil. Interestingly, the presence of ascorbic acid in an acylglycerol structure protected α-tocopherol against thermal degradation, which was not observed for the phenolic acids. Developed structured lipids containing nutraceuticals and antioxidants may directly affect nutritional properties of lipids also offering nutraceutical ingredients for food formulation.

  10. Hemin-mediated Hemolysis in Erythrocytes: Effects of Ascorbic Acid and Glutathione

    Institute of Scientific and Technical Information of China (English)

    Shu-De LI; Yan-Dan SU; Ming LI; Cheng-Gang ZOU

    2006-01-01

    In the present work, we investigated the effect of ascorbic acid and glutathione on hemolysis induced by hemin in erythrocytes. Ascorbic acid not only enhanced hemolysis, but also induced formation of thiobarbituric acid-reactive substances in the presence of hemin. It has been shown that glutathione inhibits hemin-induced hemolysis by mediating hemin degradation. Erythrocytes depleted of glutathione became very sensitive to oxidative stress induced by hemin and ascorbic acid. H2O2 was involved in heminmediated hemolysis in the presence of ascorbic acid. However, a combination of glutathione and ascorbic acid was more effective in inhibiting hemolysis induced by hemin than glutathione alone. Extracellular and intracellular ascorbic acid exhibited a similar effect on hemin-induced hemolysis or inhibition of hemininduced hemolysis by glutathione. The current study indicates that ascorbic acid might function as an antioxidant or prooxidant in hemin-mediated hemolysis, depending on whether glutathione is available.

  11. Oxidation of cumene in an aprotic medium in the presence of ascorbic acid

    Science.gov (United States)

    Smirnova, O. V.; Efimova, I. V.; Opeida, I. A.

    2015-06-01

    The process of the initiated oxidation of cumene (IPB) with oxygen under homophase conditions in the presence of ascorbic acid (AA) used over a wide range of concentrations is studied. It is shown that in this system, ascorbic acid is consumed in two ways: the auto-oxidation and the inhibition of the oxidation of cumene. The amount of ascorbic acid that participates in inhibiting the oxidation of cumene falls from 28.5 to 16.6% with a rise in the concentration of ascorbic acid in the range of 0.003-0.3 mol/L. The contribution from the rate of the oxidation of ascorbic acid to the total rate of the oxidation of the IPB-AA-DMSO-AIBN system grows from 67.2 to 92.5% with a rise in the concentration of ascorbic acid in the range of 0.01-0.3 mol/L. It is established that the most effective inhibition of the oxidation of cumene with ascorbic acid in aprotic media occurs at concentrations of ascorbic acid of up to 0.01 mol/L. A scheme for the initiated radical-chain oxidation of cumene with ascorbic acid in the aprotic medium that considers the inhibition of the oxidation of cumene with ascorbic acid and the auto-oxidation of ascorbic acid is proposed.

  12. Effect of ascorbic acid and other adjuvants on manganese absorption

    Energy Technology Data Exchange (ETDEWEB)

    Papaioannou, R.; Sohler, A.; Pfeiffer, C.C.

    1986-03-01

    Animal experiments have demonstrated that manganese is poorly absorbed from the gut and that it is rapidly removed from the blood by liver uptake and bilary excretion. Zinc supplements which are readily absorbed can induce a Mn deficiency so that Mn supplementation is necessary. Supplementation with a diet rich in Mn (high in legumes, nuts, whole grains, tea) failed to influence blood Mn levels. The present study is concerned with the route of Mn administration and the effect of various adjuvants on the absorption and availability of Mn. Oral and sublingual administration of 20 mgs of Mn as the chloride failed to elicit a blood level rise. A rise was noted after the intramuscular injection of 2.5 mgs Mn as Mn Cl/sub 2/. Blood Mn levels rose to a maximum in thirty minutes and were back to basal levels within three hours. Adjuvants such as arginine, lecithin, taurine, biotin, bioflavinoids, were tested with essentially negative results. Mn orotate also failed to increase absorption. Oral absorption was obtained with ascorbic acid in five female subjects when 20 mgs of Mn as the chloride was given orally with 1 gm of ascorbic acid. This effect was not observed with five male subjects. A 30-40% increase in blood Mn after 2 hours was found when Mn was administered with ascorbic acid in the female subjects.

  13. Ascorbic Acid Efflux and Re-uptake in Endothelial Cells: Maintenance of Intracellular Ascorbate

    OpenAIRE

    May, James M.; Qu, Zhi-chao

    2009-01-01

    Entry of vitamin C or ascorbate into most tissues requires its movement across the endothelial cell barrier of vessels. If trans-cellular ascorbate movement occurs, then it should be evident as ascorbate efflux from endothelial cells. Cultured EA.926 endothelial cells that had been loaded to about 3.5 mM intracellular ascorbate lost 70–80% of ascorbate to the medium over several hours at 37 °C via a non-saturable process that was insensitive to anion transport inhibitors and thiol reagents. O...

  14. 21 CFR 146.148 - Reduced acid frozen concentrated orange juice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Reduced acid frozen concentrated orange juice. 146... SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CANNED FRUIT JUICES Requirements for Specific Standardized Canned Fruit Juices and Beverages § 146.148 Reduced acid frozen concentrated orange juice. (a) Reduced...

  15. Treatment of irradiated mice with high-dose ascorbic acid reduced lethality.

    Directory of Open Access Journals (Sweden)

    Tomohito Sato

    Full Text Available Ascorbic acid is an effective antioxidant and free radical scavenger. Therefore, it is expected that ascorbic acid should act as a radioprotectant. We investigated the effects of post-radiation treatment with ascorbic acid on mouse survival. Mice received whole body irradiation (WBI followed by intraperitoneal administration of ascorbic acid. Administration of 3 g/kg of ascorbic acid immediately after exposure significantly increased mouse survival after WBI at 7 to 8 Gy. However, administration of less than 3 g/kg of ascorbic acid was ineffective, and 4 or more g/kg was harmful to the mice. Post-exposure treatment with 3 g/kg of ascorbic acid reduced radiation-induced apoptosis in bone marrow cells and restored hematopoietic function. Treatment with ascorbic acid (3 g/kg up to 24 h (1, 6, 12, or 24 h after WBI at 7.5 Gy effectively improved mouse survival; however, treatments beyond 36 h were ineffective. Two treatments with ascorbic acid (1.5 g/kg × 2, immediately and 24 h after radiation, 3 g/kg in total also improved mouse survival after WBI at 7.5 Gy, accompanied with suppression of radiation-induced free radical metabolites. In conclusion, administration of high-dose ascorbic acid might reduce radiation lethality in mice even after exposure.

  16. Treatment of irradiated mice with high-dose ascorbic acid reduced lethality.

    Science.gov (United States)

    Sato, Tomohito; Kinoshita, Manabu; Yamamoto, Tetsuo; Ito, Masataka; Nishida, Takafumi; Takeuchi, Masaru; Saitoh, Daizoh; Seki, Shuhji; Mukai, Yasuo

    2015-01-01

    Ascorbic acid is an effective antioxidant and free radical scavenger. Therefore, it is expected that ascorbic acid should act as a radioprotectant. We investigated the effects of post-radiation treatment with ascorbic acid on mouse survival. Mice received whole body irradiation (WBI) followed by intraperitoneal administration of ascorbic acid. Administration of 3 g/kg of ascorbic acid immediately after exposure significantly increased mouse survival after WBI at 7 to 8 Gy. However, administration of less than 3 g/kg of ascorbic acid was ineffective, and 4 or more g/kg was harmful to the mice. Post-exposure treatment with 3 g/kg of ascorbic acid reduced radiation-induced apoptosis in bone marrow cells and restored hematopoietic function. Treatment with ascorbic acid (3 g/kg) up to 24 h (1, 6, 12, or 24 h) after WBI at 7.5 Gy effectively improved mouse survival; however, treatments beyond 36 h were ineffective. Two treatments with ascorbic acid (1.5 g/kg × 2, immediately and 24 h after radiation, 3 g/kg in total) also improved mouse survival after WBI at 7.5 Gy, accompanied with suppression of radiation-induced free radical metabolites. In conclusion, administration of high-dose ascorbic acid might reduce radiation lethality in mice even after exposure.

  17. Utilization of dried roselle calyces extract in fruit juice processing

    OpenAIRE

    Kilima, Beatrice Mgaya

    2014-01-01

    There has been an increased consumption of fruit juice as consumers have become aware of the nutritional and health benefits of fruit juices. This increased consumption goes together with the growth of varieties of fruit juices and beverages offered for sale. Among these products is roselle (Hibiscus sabdariffa L.) juice, or drink, which is a good source of anthocyanins, vitamins (thiamine, riboflavin, niacin, ascorbic acid) and minerals (Ca, P, Fe). In addition, roselle is also used as flavo...

  18. Industrial production of L-ascorbic Acid (vitamin C) and D-isoascorbic acid.

    Science.gov (United States)

    Pappenberger, Günter; Hohmann, Hans-Peter

    2014-01-01

    L-ascorbic acid (vitamin C) was first isolated in 1928 and subsequently identified as the long-sought antiscorbutic factor. Industrially produced L-ascorbic acid is widely used in the feed, food, and pharmaceutical sector as nutritional supplement and preservative, making use of its antioxidative properties. Until recently, the Reichstein-Grüssner process, designed in 1933, was the main industrial route. Here, D-sorbitol is converted to L-ascorbic acid via 2-keto-L-gulonic acid (2KGA) as key intermediate, using a bio-oxidation with Gluconobacter oxydans and several chemical steps. Today, industrial production processes use additional bio-oxidation steps with Ketogulonicigenium vulgare as biocatalyst to convert D-sorbitol to the intermediate 2KGA without chemical steps. The enzymes involved are characterized by a broad substrate range, but remarkable regiospecificity. This puzzling specificity pattern can be understood from the preferences of these enyzmes for certain of the many isomeric structures which the carbohydrate substrates adopt in aqueous solution. Recently, novel enzymes were identified that generate L-ascorbic acid directly via oxidation of L-sorbosone, an intermediate of the bio-oxidation of D-sorbitol to 2KGA. This opens the possibility for a direct route from D-sorbitol to L-ascorbic acid, obviating the need for chemical rearrangement of 2KGA. Similar concepts for industrial processes apply for the production of D-isoascorbic acid, the C5 epimer of L-ascorbic acid. D-isoascorbic acid has the same conformation at C5 as D-glucose and can be derived more directly than L-ascorbic acid from this common carbohydrate feed stock.

  19. Ascorbic acid in cultured tissue of briar rose, Rosa rugosa Thunb.

    Science.gov (United States)

    Wegg, S M; Townsley, P M

    1983-04-01

    Ascorbic acid synthesis was studied using suspension cultured cells from the fleshy portion of the fruit of the rose, Rosa rugosa Thunb. Cells cultured in the dark contained ascorbic acid at a level of 13 mg/100 g wet wt. This value increased several fold when the cells were grown under light. Ascorbic acid does not accumulate in the growth medium possibly due to its rapid oxidation. L-galactono-1,4-lactone was readily converted to ascorbic acid whereas L-gulono-1,4-lactone was used to a much lesser degree. D-glucose, D-fructose, D-galactose. D-glucurono-1,4-lactone and myoinositol did not stimulate increased ascorbic acid synthesis. Reducing the sucrose content of the medium reduced the ascorbic acid content of the cells without altering cell yield.

  20. Low Dose Gamma Irradiation Does Not Affect the Quality or Total Ascorbic Acid Concentration of “Sweetheart” Passionfruit (Passiflora edulis

    Directory of Open Access Journals (Sweden)

    John B. Golding

    2015-08-01

    Full Text Available Passionfruit (Passiflora edulis, Sims, cultivar “Sweetheart” were subject to gamma irradiation at levels suitable for phytosanitary purposes (0, 150, 400 and 1000 Gy then stored at 8 °C and assessed for fruit quality and total ascorbic acid concentration after one and fourteen days. Irradiation at any dose (≤1000 Gy did not affect passionfruit quality (overall fruit quality, colour, firmness, fruit shrivel, stem condition, weight loss, total soluble solids level (TSS, titratable acidity (TA level, TSS/TA ratio, juice pH and rot development, nor the total ascorbic acid concentration. The length of time in storage affected some fruit quality parameters and total ascorbic acid concentration, with longer storage periods resulting in lower quality fruit and lower total ascorbic acid concentration, irrespective of irradiation. There was no interaction between irradiation treatment and storage time, indicating that irradiation did not influence the effect of storage on passionfruit quality. The results showed that the application of 150, 400 and 1000 Gy gamma irradiation to “Sweetheart” purple passionfruit did not produce any deleterious effects on fruit quality or total ascorbic acid concentration during cold storage, thus supporting the use of low dose irradiation as a phytosanitary treatment against quarantine pests in purple passionfruit.

  1. Low Dose Gamma Irradiation Does Not Affect the Quality or Total Ascorbic Acid Concentration of “Sweetheart” Passionfruit (Passiflora edulis)

    Science.gov (United States)

    Golding, John B.; Blades, Barbara L.; Satyan, Shashirekha; Spohr, Lorraine J.; Harris, Anne; Jessup, Andrew J.; Archer, John R.; Davies, Justin B.; Banos, Connie

    2015-01-01

    Passionfruit (Passiflora edulis, Sims, cultivar “Sweetheart”) were subject to gamma irradiation at levels suitable for phytosanitary purposes (0, 150, 400 and 1000 Gy) then stored at 8 °C and assessed for fruit quality and total ascorbic acid concentration after one and fourteen days. Irradiation at any dose (≤1000 Gy) did not affect passionfruit quality (overall fruit quality, colour, firmness, fruit shrivel, stem condition, weight loss, total soluble solids level (TSS), titratable acidity (TA) level, TSS/TA ratio, juice pH and rot development), nor the total ascorbic acid concentration. The length of time in storage affected some fruit quality parameters and total ascorbic acid concentration, with longer storage periods resulting in lower quality fruit and lower total ascorbic acid concentration, irrespective of irradiation. There was no interaction between irradiation treatment and storage time, indicating that irradiation did not influence the effect of storage on passionfruit quality. The results showed that the application of 150, 400 and 1000 Gy gamma irradiation to “Sweetheart” purple passionfruit did not produce any deleterious effects on fruit quality or total ascorbic acid concentration during cold storage, thus supporting the use of low dose irradiation as a phytosanitary treatment against quarantine pests in purple passionfruit. PMID:28231212

  2. Electrodialytic removal of nitrate from pineapple juice: effect on selected physicochemical properties, amino acids, and aroma components of the juice.

    Science.gov (United States)

    Ackarabanpojoue, Yuwadee; Chindapan, Nathamol; Yoovidhya, Tipaporn; Devahastin, Sakamon

    2015-05-01

    This study aimed at investigating the effect of nitrate removal from pineapple juice by electrodialysis (ED) on selected properties of the ED-treated juice. Single-strength pineapple juice with reduced pulp content was treated by ED to reduce the nitrate concentration to 15, 10, or 5 ppm. After ED, the removed pulp was added to the ED-treated juice and its properties, including electrical conductivity, acidity, pH, total soluble solids (TSS), color, amino acids, and selected aroma compounds, were determined and compared with those of the untreated juice. ED could reduce the nitrate content of 1 L of pineapple juice from an initial value of 50 ppm to less than 5 ppm within 30 min. A significant decrease in the electrical conductivity, acidity, pH, TSS, and yellowness, but a significant increase in the lightness, of the juice was observed upon ED. Concentrations of almost all amino acids of the ED-treated juice significantly decreased. The concentrations of 8 major compound contributors to the pineapple aroma also significantly decreased. Adding the pulp back to the ED-treated juice increased the amino acids concentrations; however, it led to a significant decrease in the concentrations of the aroma compounds.

  3. Role Of Ascorbic Acid In Imparting Tolerance To Plants Against Oxidizing Pollutants

    Directory of Open Access Journals (Sweden)

    Priyanka Sharma

    2015-08-01

    Full Text Available Ascorbic acid is an antioxidant in plants which play important role in activation of many physiological and defense mechanisms. The level of ascorbic acid in plants is determinant of its tolerance against the adverse effect of oxidizing pollutants. The present study tries to relate the variation in ascorbic acid content with the tolerance and sensitivity of two selected plant species viz. Azadirachtaindica and Pongamiapinnata by calculating their Air Pollution Tolerance Index APTI during winter season from November to March in the urban city Delhi of North India. Moreover ascorbic acid is also an important part of chloroplast it protects different components of photosynthetic system from oxidative stress. Thus to understand the role of ascorbic acid in imparting tolerance to plants against oxidizing pollutants the changes in chlorophyll content of the selected plant species with variation in ambient ozone concentration was analysed. It was found that as per APTI values Azadirachta sp. came under tolerant range with highest ascorbic acid content whereas Pongamia sp. was under intermediate range with less ascorbic acid content. It was statistically established that ozone has no significant relation with chlorophyll content of Azadirachta sp. which has the highest ascorbic acid content. Whereas ambient ozone concentrations showed significant negative relation with the chlorophyll content of Pongamia sp. p 0.05. Thus it was observed that the plants with high ascorbic acid content are tolerant and have greater ability to remediate pollutants.

  4. Water-dispersible ascorbic-acid-coated magnetite nanoparticles for contrast enhancement in MRI

    Science.gov (United States)

    Sreeja, V.; Jayaprabha, K. N.; Joy, P. A.

    2015-04-01

    Superparamagnetic iron oxide nanoparticles of size ~5 nm surface functionalized with ascorbic acid (vitamin C) form a stable dispersion in water with a hydrodynamic size of ~30 nm. The anti-oxidant property of ascorbic acid is retained after capping, as evidenced from the capability of converting methylene blue to its reduced leuco form. NMR relaxivity studies show that the ascorbic-acid-coated superparamagnetic iron oxide aqueous nanofluid is suitable as a contrast enhancement agent for MRI applications, coupled with the excellent biocompatibility and medicinal values of ascorbic acid.

  5. The kinetics of oxidation of bilirubin and ascorbic acid in solution

    Science.gov (United States)

    Solomonov, A. V.; Rumyantsev, E. V.; Kochergin, B. A.; Antina, E. V.

    2012-07-01

    The results of a comparative study of the oxidation of bilirubin, ascorbic acid, and their mixture in aqueous solutions under the action of air oxygen and hydrogen peroxide are presented. The observed and true rate constants for the oxidation reactions were determined. It was shown that the oxidation of tetrapyrrole pigment occurred under these conditions bypassing the stage of biliverdin formation to monopyrrole products. Simultaneous oxidation of bilirubin and ascorbic acid was shown to be accompanied by the inhibition of ascorbic acid oxidation by bilirubin, whereas ascorbic acid itself activated the oxidation of bilirubin.

  6. Fluctuations in phenolic content, ascorbic acid and total carotenoids and antioxidant activity of fruit beverages during storage

    Directory of Open Access Journals (Sweden)

    C. Castro-López

    2016-09-01

    Full Text Available Stability of the total phenolic content, ascorbic acid, total carotenoids and antioxidant activity in eight fruit beverages was analyzed. The influence of storage temperature (4, 8 and 11 °C during the product shelf-life (20 days was evaluated. Pomegranate Juice presented the highest values for antioxidant activity by DPPH·− assay (552.93 ± 6.00 GAE μg mL−1, total carotenoids (3.18 ± 0.11 βCE μg mL−1, and total phenolic content (3967.07 ± 2.47 GAE μg mL−1; while Splash Blend recorded the highest levels of ascorbic acid (607.39 ± 2.13 AAE μg mL−1. The antioxidant capacity was stable at 4 and 8 °C for the first 8 days of storage; while carotenoids and ascorbic acid were slightly degraded through the storage time, possibly due to oxidation and/or reactions with other compounds. The results suggest that the observed variation during testing could be related to storage conditions of the final product.

  7. Synergistic inhibitory effect of ascorbic acid and acetylsalicylic acid on prostaglandin E2 release in primary rat microglia.

    Science.gov (United States)

    Fiebich, Bernd L; Lieb, Klaus; Kammerer, Norbert; Hüll, Michael

    2003-07-01

    Ascorbic acid (vitamin C) has been suggested to protect cerebral tissue in a variety of pathophysiological situations such as head trauma, ischemia or Alzheimer's disease. Most of these protective actions have been attributed to the antioxidative capacity of ascorbic acid. Besides the presence of elevated levels of oxygen radicals, prostaglandins produced by neurones and microglial cells seem to play an important role in prolonged tissue damage. We investigated whether ascorbic acid alone inhibits prostaglandin E2 (PGE2) synthesis and may augment the inhibitory effect of acetylsalicylic acid on prostaglandin synthesis. Ascorbic acid dose-dependently inhibited PGE2 synthesis in lipopolysaccharide-treated primary rat microglial cells (IC50 = 3.70 micro m). In combination with acetylsalicylic acid (IC50 = 1.85 micro m), ascorbic acid augmented the inhibitory effect of acetylsalicylic acid on PGE2 synthesis (IC50 = 0.25 micro m in combination with 100 micro m ascorbic acid). Ascorbic acid alone or in combination with acetylsalicylic acid did not inhibit cyclooxygenase-2 (COX-2) protein synthesis but inhibited COX-2 enzyme activity. Our results show that ascorbic acid and acetylsalicylic acid act synergistically in inhibiting PGE2 synthesis, which may help to explain a possible protective effect of ascorbic acid in various brain diseases.

  8. The effect of water, ascorbic acid, and cranberry derived supplementation on human urine and uropathogen adhesion to silicone rubber

    NARCIS (Netherlands)

    Habash, MB; Van der Mei, HC; Busscher, HJ; Reid, G

    1999-01-01

    In this study, urine was collected from groups of volunteers following the consumption of water, ascorbic acid, or cranberry supplements. Only ascorbic acid intake consistently produced acidic urine. Photospectroscopy data indicated that increased water consumption produced urine with lower protein

  9. Evaluation of accelerated UV and thermal testing for benzene formation in beverages containing benzoate and ascorbic acid.

    Science.gov (United States)

    Nyman, Patricia J; Wamer, Wayne G; Begley, Timothy H; Diachenko, Gregory W; Perfetti, Gracia A

    2010-04-01

    Under certain conditions, benzene can form in beverages containing benzoic and ascorbic acids. The American Beverage Assn. (ABA) has published guidelines to help manufacturers mitigate benzene formation in beverages. These guidelines recommend accelerated testing conditions to test product formulations, because exposure to ultraviolet (UV) light and elevated temperature over the shelf life of the beverage may result in benzene formation in products containing benzoic and ascorbic acids. In this study, the effects of UVA exposure on benzene formation were determined. Benzene formation was examined for samples contained in UV stabilized and non-UV stabilized packaging. Additionally, the usefulness of accelerated thermal testing to simulate end of shelf-life benzene formation was evaluated for samples containing either benzoic or ascorbic acid, or both. The 24 h studies showed that under intense UVA light benzene levels increased by as much as 53% in model solutions stored in non-UV stabilized bottles, whereas the use of UV stabilized polyethylene terephthalate bottles reduced benzene formation by about 13% relative to the non-UV stabilized bottles. Similar trends were observed for the 7 d study. Retail beverages and positive and negative controls were used to study the accelerated thermal testing conditions. The amount of benzene found in the positive controls and cranberry juice suggests that testing at 40 degrees C for 14 d may more reliably simulate end of shelf-life benzene formation in beverages. Except for cranberry juice, retail beverages were not found to contain detectable amounts of benzene (<0.05 ng/g) at the end of their shelf lives.

  10. Effect of Ascorbic Acid on Lipid Peroxidation Induced by Ceftazidime

    Directory of Open Access Journals (Sweden)

    Devbhuti P*,1

    2011-01-01

    Full Text Available Lipid peroxidation is the oxidative deterioration of polyunsaturated lipids which is a free radical related process and responsible for thedevelopment of many diseases and disorders like diabetes mellitus, hypertension, cancer etc. End products of lipid peroxidation aremalondialdehyde (MDA, 4-hydroxy-2-nonenal (4-HNE, etc. which are the ultimate mediator of toxicity. Antioxidants have the capability toinhibit lipid peroxidation. Keeping in mind this fact, the present in vitro study was carried out to evaluate lipid peroxidation induction potential of ceftazidime, a cephalosporin antibiotic and its suppression with ascorbic acid considering some laboratory markers of lipid peroxidation like MDA, 4-HNE and reduced glutathione (GSH. Goat liver was used as the lipid source. After treatment of the liver homogenate with drug and/or antioxidant the levels of 4-HNE, MDA and GSH were estimated in different samples at different hours of incubation. The results showed that the drug ceftazidime could significantly induce lipid peroxidation and the antioxidant ascorbic acid has the capability to inhibit ceftazidime-inducedlipid peroxidation.

  11. Development of pectin films with pomegranate juice and citric acid.

    Science.gov (United States)

    Azeredo, Henriette M C; Morrugares-Carmona, Rosario; Wellner, Nikolaus; Cross, Kathryn; Bajka, Balazs; Waldron, Keith W

    2016-05-01

    The influence of pomegranate juice (PJ, replacing water as solvent) and citric acid (CA) on properties of pectin films was studied. PJ provided the films with a bright red color, and acted as a plasticizer. Increasing PJ/water ratio from 0/100 to 100/0 resulted in enhanced elongation (from 2% to 20%), decreased strength (from 10 to anthocyanins.

  12. Comparison and combination effects on antioxidant power of curcumin with gallic acid, ascorbic acid, and xanthone.

    Science.gov (United States)

    Naksuriya, Ornchuma; Okonogi, Siriporn

    2015-04-01

    Curcumin has been extensively reported as a potential natural antioxidant. However, there was no data on activity comparison as well as the biological interactions of curcumin with other natural antioxidants. The aim of the present study was to investigate the antioxidant power of curcumin in comparison with three important natural antioxidants; gallic acid, ascorbic acid, and xanthone on free radical scavenging action and their combination effects on this activity. The results indicated that the activities of these compounds were dose-dependent. The 50% effective concentration (EC50) of curcumin was found to be 11 μg/mL. Curcumin showed significantly higher antioxidant activity than ascorbic acid and xanthone but less than gallic acid. Interestingly, curcumin revealed synergistic antioxidant effect when combined with gallic acid whereas the antagonistic effect occurred in curcumin combination with ascorbic acid or xanthone. These results suggest that curcumin-gallic acid combination is the potential antioxidant mixture to be used in place of the individual substance whereas using of curcumin in combination with ascorbic acid or xanthone should be avoid.

  13. The Oxidation of Ascorbic Acid by Hexacyanoferrate(III) Ion in Acidic Aqueous Media.

    Science.gov (United States)

    Martins, Luis J. A.; da Costa, J. Barbosa

    1988-01-01

    Describes a kinetic and mechanistic investigation of ascorbic acid by a substitution-inert complex in acidic medium suitable for the undergraduate level. Discusses obtaining the second order rate constant for the rate determining step at a given temperature and comparison with the value predicted on the basis of the Marcus cross-relation. (CW)

  14. Plant resistance mechanisms to air pollutants: rhythms in ascorbic acid production during growth under ozone stress

    Energy Technology Data Exchange (ETDEWEB)

    Lee, E.H. (Climate Stress Laboratory, USDA, ARS, Beltsville, MD (United States))

    1991-01-01

    Relationships between ozone (O3) tolerance and leaf ascorbic acid concentrations in O3-susceptible (O3-S) 'Hark' and O3-resistant (O3-R) 'Hood' soybean, Glycine max (L.) Merr., cultivars were examined with high-performance liquid chromatography (HPLC). Leaf samples were analyzed at 4 intervals during a 24 h period. Soybean cultivars grown in the greenhouse with charcoal filtered (CF) and nonfiltered (NF) air showed daily oscillations in ascorbic acid production. Highest ascorbic acid levels in leaves during light coincided with highest concentrations of photochemical oxidants in the atmosphere at 2:00 p.m. The resistant genotype produced more ascorbic acid in its trifoliate leaves than did the corresponding susceptible genotype. Under CF air (an O3-reduced environment) O3-S and O3-R cultivars showed rhythms in ascorbic acid production. In NF air (an O3 stress environment) the O3-R cultivar alone showed rhythms in ascorbic acid production. Results indicated that superior O3 tolerance in the Hood soybean cultivar (compared with Hark) was associated with a greater increase in endogenous levels of ascorbic acid. Ascorbic acid may scavenge free radicals and thereby protect cells from injury by O3 or other oxyradical products. Plants defend themselves against photochemical oxidant stress, such as O3, by several mechanisms. Experimental evidence indicates that antioxidant defense systems existing in plant tissues may function to protect cellular components from deleterious effects of photochemical oxidants through endogenous and exogenous controls.

  15. Ascorbic Acid may Exacerbate Aspirin-Induced Increase in Intestinal Permeability.

    Science.gov (United States)

    Sequeira, Ivana R; Kruger, Marlena C; Hurst, Roger D; Lentle, Roger G

    2015-09-01

    Ascorbic acid in combination with aspirin has been used to prevent aspirin-induced oxidative GI damage. We aimed to determine whether ascorbic acid reduces or prevents aspirin-induced changes in intestinal permeability over a 6-hr period using saccharidic probes mannitol and lactulose. The effects of administration of 600 mg aspirin alone, 500 mg ascorbic acid alone and simultaneous dosage of both agents were compared in a cross-over study in 28 healthy female volunteers. These effects were also compared with that of a placebo. The ability of ascorbic acid to mitigate the effects of aspirin when administered either half an hour before or after dosage with aspirin was also assessed in 19 healthy female volunteers. The excretion of lactulose over the 6-hr period was augmented after consumption of either aspirin or ascorbic acid compared with that after consumption of placebo. Dosage with ascorbic acid alone augmented the excretion of lactulose more than did aspirin alone. Simultaneous dosage with both agents augmented the excretion of lactulose in an additive manner. The timing of dosage with ascorbic acid in relation to that with aspirin had no significant effect on the excretion of the two sugars. These findings indicate that ascorbic acid does not prevent aspirin-induced increase in gut permeability rather that both agents augment it to a similar extent. The additive effect on simultaneous dosage with both agents in augmenting the absorption of lactulose suggests that each influences paracellular permeability by different pathways.

  16. Ascorbic Acid Influences the Development and Immunocompetence of Larval Heliothis virescens

    Science.gov (United States)

    We report that ascorbic acid, which is known to be a free radical scavenger, to be important not only in insect development but also in larval resistance to baculovirus infection. We sequentially elevated the ascorbic acid content in diet and evaluated the effect on larval H. virescens development ...

  17. Ascorbic acid effects on in vitro maturation of mouse oocyte with or ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... nutrient-derived antioxidants like ascorbic acid (vitamin ... this study was to determine whether supplementation with ascorbic acid could ... 5% FBS and 100 mIU/ml recombinant human FSH (Gonal-F; N. V. .... µM/ml) promote cell growth whereas the higher concen- ... biochemistry in animals and plants.

  18. Reduction of nitrobenzene with alkaline ascorbic acid: Kinetics and pathways

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Chenju, E-mail: cliang@nchu.edu.tw [Department of Environmental Engineering, National Chung Hsing University 250, Kuo-kuang Road, Taichung 402, Taiwan (China); Lin, Ya-Ting [Department of Environmental Engineering, Chung Yuan Christian University, 200 Chung Pei Road, Chung Li District, Taoyuan City 320, Taiwan (China); Shiu, Jia-Wei [Department of Environmental Engineering, National Chung Hsing University 250, Kuo-kuang Road, Taichung 402, Taiwan (China)

    2016-01-25

    Highlights: • Alkaline ascorbic acid (a.k.a. vitamin C) is capable of reductively degrading NB. • The pH above the pK{sub a2} of ascorbic acid increases reductive electron transfer to NB. • The rate equation for the reactions between NB and AA is determined. • NSB, AZOXY, and AZO are identified as intermediates and aniline as a final product. • Alkaline pH is essential for AA remediation of NB contaminated soils. - Abstract: Alkaline ascorbic acid (AA) exhibits the potential to reductively degrade nitrobenzene (NB), which is the simplest of the nitroaromatic compounds. The nitro group (NO{sub 2}{sup −}) of NB has a +III oxidation state of the N atom and tends to gain electrons. The effect of alkaline pH ranging from 9 to 13 was initially assessed and the results demonstrated that the solution pH, when approaching or above the pK{sub a2} of AA (11.79), would increase reductive electron transfer to NB. The rate equation for the reactions between NB and AA at pH 12 can be described as r = ((0.89 ± 0.11) × 10{sup −4} mM{sup 1−(a} {sup +} {sup b)} h{sup −1}) × [NB]{sup a} {sup =} {sup 1.35} {sup ±} {sup 0.10}[AA]{sup b} {sup =} {sup 0.89} {sup ±} {sup 0.01}. The GC/MS analytical method identified nitrosobenzene, azoxybenzene, and azobenzene as NB reduction intermediates, and aniline (AN) as a final product. These experimental results indicate that the alkaline AA reduction of NB to AN mainly proceeds via the direct route, consisting of a series of two-electron or four-electron transfers, and the condensation reaction plays a minor route. Preliminary evaluation of the remediation of spiked NB contaminated soils revealed that maintenance of alkaline pH and a higher water to soil ratio are essential for a successful alkaline AA application.

  19. Induction of cell death by ascorbic acid derivatives in human renal carcinoma and glioblastoma cell lines.

    Science.gov (United States)

    Makino, Y; Sakagami, H; Takeda, M

    1999-01-01

    Sodium-L-ascorbate, L-ascorbic acid, D-isoascorbic acid, sodium 5,6-benzylidene-L-ascorbate and sodium-6-beta-O-galactosyl-L-ascorbate, which produce ascorbyl radicals during the oxidative degradation, also induced cytotoxicity against cultured human renal carcinoma (TC-1) and glioblastoma multiform tumor (T98G) cell lines. On the other hand, L-ascorbic acid 2-phosphate magnesium and L-ascorbic acid 2-sulfate dipotassium salt, which do not produce the ascorbyl radical, were inactive. This suggests the possible role of the ascorbyl radical for cell death induction. T98G cells were more resistant to ascorbate analogs than TC-1 and HL-60 cells, possibly due to higher intracellular glutathione concentrations. Ascorbate treatment induced rapid elevation of both intracellular concentration of cAMP and Ca2+ in HL-60 cells, but not in TC-1 and T98G cells. However, the elevation of cAMP by theophyline and N,2-dibutyryl adenosine 3,5 cyclic monophosphate (dibutyryl cAMP) resulted in a decrease in the viable cell number. This suggests the possible role of cAMP for ascorbate-induced cell death.

  20. Developmental aspects and factors influencing the synthesis and status of ascorbic Acid in the pig.

    Science.gov (United States)

    Mahan, D C; Ching, S; Dabrowski, K

    2004-01-01

    Ascorbic acid synthesis in the pig occurs at mid-pregnancy, but activity of the enzyme l-gulono-gamma-lactone oxidase (GLO) declines thereafter during gestation and remains low when the pig nurses the sow. During late gestation the ascorbic acid concentration in the fetus increases, but serum and liver ascorbic acid concentration in the sow declines without affecting the dam's liver GLO activity. It is presumed that as gestation progresses an increased amount of maternal ascorbic acid is transferred to the fetus and to the mammary gland. Colostrum and milk are rich sources of the vitamin and supply the nursing pig with ascorbic acid. The available data suggest that high amounts of ascorbic acid appear to suppress liver GLO activity in the pig. Upon weaning, when exogenous vitamin C is generally not provided, liver GLO activity and serum ascorbic acid increases. During the initial periods postweaning, some reports have indicated growth benefits of supplemental vitamin C. Body tissues differ in their concentrations of ascorbic acid, but tissues of high metabolic need generally have greater concentrations. The corpus luteum in the female, the testis in the male, and the adrenal glands in all pigs contain greater concentrations of the vitamin. Knockout genes preventing ascorbic acid synthesis in pigs have demonstrated poor skeletal and collagen formation and poor antioxidant protection. Under periods of stress ascorbic acid declines in the adrenal, but the pig rapidly recovers to its resting state once the stressor agent is removed. Although there are periods when supplemental vitamin C has been shown to promote pig performance (e.g., during high environmental stress and early postweaning), supplemental vitamin C has not been shown to routinely enhance pig performance.

  1. Thermal stability of ascorbic acid and ascorbic acid oxidase in african cowpea leaves ( Vigna unguiculata ) of different maturities.

    Science.gov (United States)

    Wawire, Michael; Oey, Indrawati; Mathooko, Francis; Njoroge, Charles; Shitanda, Douglas; Hendrickx, Marc

    2011-03-09

    Cowpea, an African leafy vegetable ( Vigna unguiculata ), contains a high level of vitamin C. The leaves harvested at 4-9 weeks are highly prone to vitamin C losses during handling and processing. Therefore, the purpose of this research was to study the effect of thermal treatment on the stability of ascorbic acid oxidase (AAO), total vitamin C content (l-ascorbic acid, l-AA), and dehydroascorbic acid (DHAA) and l-AA/DHAA ratio in cowpea leaves harvested at different maturities (4, 6, and 8 weeks old). The results showed that AAO activity, total vitamin C content, and l-AA/DHAA ratio in cowpea leaves increased with increasing maturity (up to 8 weeks). Eight-week-old leaves were the best source of total vitamin C and showed a high ratio of l-AA/DHAA (4:1). Thermal inactivation of AAO followed first-order reaction kinetics. Heating at temperatures above 90 °C for short times resulted in a complete AAO inactivation, resulting in a protective effect of l-AA toward enzyme-catalyzed oxidation. Total vitamin C in young leaves (harvested at 4 and 6 weeks) was predominantly in the form of DHAA, and therefore temperature treatment at 30-90 °C for 10 min decreased the total vitamin C content, whereas total vitamin C in 8-week-old cowpea leaves was more than 80% in the form of l-AA, so that a high retention of the total vitamin C can be obtained even after heating and/or reheating (30-90 °C for 10 min) before consumption. The results indicated that the stability of total vitamin C in situ was strongly dependent on the plant maturity stage and the processing conditions applied.

  2. Comparative analysis of ascorbic acid in human milk and infant formula using varied milk delivery systems

    Directory of Open Access Journals (Sweden)

    Dickton Darby

    2008-08-01

    Full Text Available Abstract Background The expression of human milk for later use is on the rise. Bottle systems are used to deliver the expressed milk. Research has shown that storage of both human milk and artificial baby milk, or infant formula, leads to a loss of ascorbic acid (commonly called Vitamin C. As milk is removed from the bottle during feeding and replaced by ambient air, it is unknown if loss of ascorbic acid occurs during the course of a feeding. The purpose of this study is to investigate the effect of the milk delivery system on levels of ascorbic acid in human milk and infant formula. The objectives are to 1 determine changes in ascorbic acid concentration during a 20 minute "feed," 2 determine if there is a difference in ascorbic acid concentration between delivery systems, and 3 evaluate if any differences are of clinical importance. Methods Commonly available bottles were used for comparison of bottle delivery systems. Mature human milk was standardized to 42 mg/L of ascorbic acid. Infant formula with iron and infant formula with docosahexanoic acid were used for the formula samples. Each sample was analyzed for ascorbic acid concentration at baseline (0, 5, 10, 15, and 20 minutes. Each collection of samples was completed in triplicate. Samples were analyzed for ascorbic acid using normal-phase high performance liquid chromatography. Results Ascorbic acid concentration declined in all bottle systems during testing, Differences between the bottle systems were noted. Ascorbic acid concentrations declined to less than 40% of recommended daily intake for infants in 4 of the bottles systems at the 20 minute sampling. Conclusion The bottle systems used in this study had measurable decreases in the mean concentration of ascorbic acid. More research is needed to determine if the observed decreases are related to lower plasma ascorbic acid concentration in infants exclusively bottle fed. The decrease of ascorbic acid concentration observed in both

  3. CITOGENETICS EFFECTS INDUCED BY THE ASCORBIC ACID TREATMENT OF LARIX DECIDUA MILL. SSP. CARPATICA AND PICEA ABIES (L. KARST

    Directory of Open Access Journals (Sweden)

    Ioana Ieremia

    2006-08-01

    Full Text Available The paper present the influence of ascorbic acid upon the mitotic division of Larix decidua Mill ssp. carpatica and Picea abies (L. Karst. The treatment is applied of two variants, germinated seed in ascorbic acid (variantAand germinated seeds in disttilate water, than treated with ascorbic acid in 3 concentrations (variant B.

  4. The effects of ascorbic acid on cartilage metabolism in guinea pig articular cartilage explants.

    Science.gov (United States)

    Clark, Amy G; Rohrbaugh, Amy L; Otterness, Ivan; Kraus, Virginia B

    2002-03-01

    Ascorbic acid has been associated with the slowing of osteoarthritis progression in guinea pig and man. The goal of this study was to evaluate transcriptional and translational regulation of cartilage matrix components by ascorbic acid. Guinea pig articular cartilage explants were grown in the presence of L-ascorbic acid (L-Asc), D-isoascorbic acid (D-Asc), sodium L-ascorbate (Na L-Asc), sodium D-isoascorbate (Na D-Asc), or ascorbyl-2-phosphate (A2P) to isolate and analyze the acidic and nutrient effects of ascorbic acid. Transcription of type II collagen, prolyl 4-hydroxylase (alpha subunit), and aggrecan increased in response to the antiscorbutic forms of ascorbic acid (L-Asc, Na L-Asc, and A2P) and was stereospecific to the L-forms. Collagen and aggrecan synthesis also increased in response to the antiscorbutic forms but only in the absence of acidity. All ascorbic acid forms tended to increase oxidative damage over control. This was especially true for the non-nutrient D-forms and the high dose L-Asc. Finally, we investigated the ability of chondrocytes to express the newly described sodium-dependent vitamin C transporters (SVCTs). We identified transcripts for SVCT2 but not SVCT1 in guinea pig cartilage explants. This represents the first characterization of SVCTs in chondrocytes. This study confirms that ascorbic acid stimulates collagen synthesis and in addition modestly stimulates aggrecan synthesis. These effects are exerted at both transcriptional and post-transcriptional levels. The stereospecificity of these effects is consistent with chondrocyte expression of SVCT2, shown previously to transport L-Asc more efficiently than D-Asc. Therefore, this transporter may be the primary mechanism by which the L-forms of ascorbic acid enter the chondrocyte to control matrix gene activity.

  5. The browning kinetics of the non-enzymatic browning reaction in L-ascorbic acid/basic amino acid systems

    Directory of Open Access Journals (Sweden)

    Ai-Nong YU

    Full Text Available Abstract Under the conditions of weak basis and the reaction temperature range of 110-150 °C, lysine, arginine and histidine were reacted with L-ascorbic acid at equal amount for 30-150 min, respectively and the formation of browning products was monitored with UV–vis spectrometry. The kinetic characteristics of their non-enzymatic browning reaction were investigated. The study results indicated that the non-enzymatic browning reaction of these three amino acids with L-ascorbic acid to form browning products was zero-order reaction. The apparent activation energies for the formation of browning products from L-ascorbic acid/lysine, L-ascorbic acid/arginine and L-ascorbic acid/histidine systems were 54.94, 50.08 and 35.31kJ/mol. The activation energy data indicated the degree of effects of reaction temperature on non-enzymatic browning reaction. Within the temperature range of 110-150 °C, the reaction rate of L-ascorbic acid/lysine system was the fastest one, followed by that of the L-ascorbic acid/arginine system. The reaction rate of L-ascorbic acid/histidine system was the slowest one. Based on the observed kinetic data, the formation mechanisms of browning products were proposed.

  6. Role of Vitamin C (ascorbic acid) on human health- A review ...

    African Journals Online (AJOL)

    These variations are unusual and point to the need for further research to establish ... The RDA for vitamin C should be more than the amount needed to prevent the ... Increased consumption of ascorbic acid raises serum ascorbic levels and could ... Keywords: Vitamin C, cancer, blood pressure, drug metabolism, immunity.

  7. Effects of palmitoyl-KVK-L-ascorbic acid on skin wrinkles and pigmentation.

    Science.gov (United States)

    Kim, Hyeong Mi; An, Hyo Sun; Bae, Jung-Soo; Kim, Jung Yun; Choi, Chi Ho; Kim, Ju Yeon; Lim, Joo Hyuck; Choi, Joon-Hun; Song, Hyunnam; Moon, Sung Ho; Park, Young Jun; Chang, Shin-Jae; Choi, Sun Young

    2017-07-01

    Wrinkle formation and abnormal pigmentation are major clinical alterations associated with skin aging. As the aim of our study was to investigate the effects of palmitoyl-KVK-L-ascorbic acid on skin aging, the anti-wrinkle and depigmentation effects of palmitoyl-KVK-L-ascorbic acid were evaluated by measuring collagen expression in dermal fibroblast cells and inhibition of melanogenesis in B16F1 cells, respectively. The anti-aging effect of palmitoyl-KVK-L-ascorbic acid cream was also evaluated against a placebo cream in a clinical trial. Our results confirmed that the expression of type Ι collagen in dermal fibroblast cells treated with palmitoyl-KVK-L-ascorbic acid (0.1-4 μg/mL) increased in a dose-dependent manner. In B16F1 cells, treatment with 20 μg/mL palmitoyl-KVK-L-ascorbic acid reduced the melanin content by approximately 20% compared to alpha-melanocyte stimulating hormone treatment. In the clinical trial, application of palmitoyl-KVK-L-ascorbic acid cream led to an improvement in skin roughness and lightness in 12 and 8 weeks, respectively. Our data show that palmitoyl-KVK-L-ascorbic acid is an effective anti-aging agent that reduces wrinkles and abnormal skin pigmentation.

  8. Ascorbic acid increases demethylation in somatic cell nuclear transfer embryos of the pig (

    Directory of Open Access Journals (Sweden)

    Minghui Zhao

    2017-07-01

    Full Text Available Objective Investigated the effect and mechanism of ascorbic acid on the development of porcine embryos produced by somatic cell nuclear transfer (SCNT. Methods Porcine embryos were produced by SCNT and cultured in the presence or absence of ascorbic acid. Ten-eleven translocation 3 (TET3 in oocytes was knocked down by siRNA injection. After ascorbic acid treatment, reprogramming genes were analyzed by realtime reverse transcription-polymerase chain reaction (RT-PCR. Furthermore, relative 5-methylcytosine and 5-hydroxymethylcytosine content in pronucleus were detected by realtime PCR. Results Ascorbic acid significantly increased the development of porcine embryos produced by SCNT. After SCNT, transcript levels of reprogramming genes, Pou5f1, Sox2, and Klf were significantly increased in blastocysts. Furthermore, ascorbic acid reduced 5-methylcytosine content in pronuclear embryos compared with the control group. Knock down of TET3 in porcine oocytes significantly prevents the demethylation of somatic cell nucleus after SCNT, even if in the presence of ascorbic acid. Conclusion Ascorbic acid enhanced the development of porcine SCNT embryos via the increased TET3 mediated demethylation of somatic nucleus.

  9. Polyethylene glycol plus ascorbic acid for bowel preparation in chronic kidney disease.

    Science.gov (United States)

    Lee, Jae Min; Keum, Bora; Yoo, In Kyung; Kim, Seung Han; Choi, Hyuk Soon; Kim, Eun Sun; Seo, Yeon Seok; Jeen, Yoon Tae; Chun, Hoon Jai; Lee, Hong Sik; Um, Soon Ho; Kim, Chang Duck; Kim, Myung Gyu; Jo, Sang Kyung

    2016-09-01

    The safety of polyethylene glycol plus ascorbic acid has not been fully investigated in patients with renal insufficiency. High-dose ascorbic acid could induce hyperoxaluria, thereby causing tubule-interstitial nephritis and renal failure. This study aims to evaluate the safety and efficacy of polyethylene glycol plus ascorbic acid in patients with chronic kidney disease.We retrospectively reviewed prospectively collected data on colonoscopy in patients with impaired renal function. Patients were divided into 2 groups: 2 L polyethylene glycol plus ascorbic acid (n = 61) and 4 L polyethylene glycol (n = 80). The safety of the 2 groups was compared by assessing the differences in laboratory findings before and after bowel cleansing.The laboratory findings were not significantly different before and after the administration of 2 L polyethylene glycol plus ascorbic acid or 4 L polyethylene glycol. In both groups, the estimated glomerular filtration rate was not influenced by the administration of the bowel-cleansing agent. Patients' reports on tolerance and acceptability were better in the 2 L polyethylene glycol plus ascorbic acid group than in the 4 L polyethylene glycol group.The 2 L polyethylene glycol plus ascorbic acid solution is a safe choice for bowel preparation before colonoscopy in patients with impaired renal function.

  10. Effects of ascorbic acid and antioxidants on color, lipid oxidation and volatiles of irradiated ground beef

    Science.gov (United States)

    Ahn, D. U.; Nam, K. C.

    2004-09-01

    Beef loins with 3 different aging times after slaughter were ground, added with none, 0.1% ascorbic acid, 0.01% sesamol+0.01% α-tocopherol, or 0.1% ascorbic acid+0.01% sesamol+0.01% tocopherol. The meats were packaged in oxygen-permeable bags, irradiated at 2.5 kGy, and color, oxidation-reduction potential (ORP), lipid oxidation and volatile profiles were determined. Irradiation decreased the redness of ground beef, and visible color of beef changed from a bright red to a green/brown depending on the age of meat. Addition of ascorbic acid prevented color changes in irradiated beef, and the effect of ascorbic acid became greater as the age of meat or storage time after irradiation increased. The ground beef added with ascorbic acid had lower ORP than control, and the low ORP of meat helped maintaining the heme pigments in reduced form. During aerobic storage, S-volatiles disappeared while volatile aldehydes significantly increased in irradiated beef. Addition of ascorbic acid at 0.1% or sesamol+α-tocopherol at each 0.01% level to ground beef prior to irradiation were effective in reducing lipid oxidation and S-volatiles. As storage time increased, however, the antioxidant effect of sesamol+tocopherol in irradiated ground beef was superior to that of ascorbic acid.

  11. Effects of ascorbic acid and antioxidants on color, lipid oxidation and volatiles of irradiated ground beef

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, D.U. E-mail: duahn@iastate.edu; Nam, K.C

    2004-10-01

    Beef loins with 3 different aging times after slaughter were ground, added with none, 0.1% ascorbic acid, 0.01% sesamol+0.01% {alpha}-tocopherol, or 0.1% ascorbic acid+0.01% sesamol+0.01% tocopherol. The meats were packaged in oxygen-permeable bags, irradiated at 2.5 kGy, and color, oxidation-reduction potential (ORP), lipid oxidation and volatile profiles were determined. Irradiation decreased the redness of ground beef, and visible color of beef changed from a bright red to a green/brown depending on the age of meat. Addition of ascorbic acid prevented color changes in irradiated beef, and the effect of ascorbic acid became greater as the age of meat or storage time after irradiation increased. The ground beef added with ascorbic acid had lower ORP than control, and the low ORP of meat helped maintaining the heme pigments in reduced form. During aerobic storage, S-volatiles disappeared while volatile aldehydes significantly increased in irradiated beef. Addition of ascorbic acid at 0.1% or sesamol+{alpha}-tocopherol at each 0.01% level to ground beef prior to irradiation were effective in reducing lipid oxidation and S-volatiles. As storage time increased, however, the antioxidant effect of sesamol+tocopherol in irradiated ground beef was superior to that of ascorbic acid.

  12. Simple determination of L-ascorbic acid on TLC by visual detection using autocatalytic reaction.

    Science.gov (United States)

    Akasaka, Kazuaki

    2013-01-01

    The L-ascorbic acid concentration in beverages was measured after separation by silica gel thin layer chromatography (TLC) by visually determining the time in autocatalytic reaction for the L-ascorbic acid spot to turn the same yellow color of the background and disappear (the end time of the induction period) after spraying the slide with a 3,6-dihydroxyxanthane solution. There was a good linear relationship between the end time of the induction period and the concentration of L-ascorbic acid for concentrations in the range of 5.0 - 20 mM (r(2) = 0.9944). In addition, there was a good relationship expressed by a quadratic equation in the concentration range of 0.1 - 5.0 mM (r(2) = 0.9975). The relative standard deviations of the L-ascorbic acid values for 3 beverages (2.2 - 8.6 mM) were less than 5% (n = 5), and the recovery of 5.0 mM L-ascorbic acid from 4 beverages (0.7 - 7 mM) was 97 - 110%. A good correlation was also observed between the L-ascorbic acid values of 23 beverages (0 - 86 mM) determined by the proposed TLC method and the colorimetric method contained in a commercially available kit for L-ascorbic acid (r(2) = 0.9945).

  13. Depletion of Ascorbic Acid Restricts Angiogenesis and Retards Tumor Growth in a Mouse Model

    Directory of Open Access Journals (Sweden)

    Sucheta Telang

    2007-01-01

    Full Text Available Angiogenesis requires the deposition of type IV collagen by endothelial cells into the basement membrane of new blood vessels. Stabilization of type IV collagen triple helix depends on the hydroxylation of proline, which is catalyzed by the iron-containing enzyme prolyl hydroxylase. This enzyme, in turn, requires ascorbic acid to maintain the enzyme-bound iron in its reduced state. We hypothesized that dietary ascorbic acid might be required for tumor angiogenesis and, therefore, tumor growth. Here, we show that, not surprisingly, ascorbic acid is necessary for the synthesis of collagen type IV by human endothelial cells and for their effective migration and tube formation on a basement membrane matrix. Furthermore, ascorbic acid depletion in mice incapable of synthesizing ascorbic acid (Gulo-/- dramatically restricts the in vivo growth of implanted Lewis lung carcinoma tumors. Histopathological analyses of these tumors reveal poorly formed blood vessels, extensive hemorrhagic foci, and decreased collagen and von Willebrand factor expression. Our data indicate that ascorbic acid plays an essential role in tumor angiogenesis and growth, and that restriction of ascorbic acid or pharmacological inhibition of prolyl hydroxylase may prove to be novel therapeutic approaches to the treatment of cancer.

  14. Cranberry Juice and Combinations of Its Organic Acids Are Effective against Experimental Urinary Tract Infection.

    Science.gov (United States)

    Jensen, Heidi D; Struve, Carsten; Christensen, Søren B; Krogfelt, Karen A

    2017-01-01

    The antibacterial effect of cranberry juice and the organic acids therein on infection by uropathogenic Escherichia coli was studied in an experimental mouse model of urinary tract infection (UTI). Reduced bacterial counts were found in the bladder (P juice. Commercially available cranberry juice cocktail also significantly reduced (P juice (P juice, were tested in combination and individually. The four organic acids also decreased bacterial levels in the bladder when administered together (P juice on UTI can be obtained by administering a combination of malic acid and either citric or quinic acid. This study show for the first time that cranberry juice reduce E. coli colonization of the bladder in an experimental mouse model of urinary tract infection and that the organic acids are active agents.

  15. THE COMPARISON OF ACID ASCORBIC CONTENT DURING PROCESSING OF SOME VEGETABLES AND FRUITS

    Directory of Open Access Journals (Sweden)

    Marcel Avramiuc

    2015-07-01

    Full Text Available In this work there was searched the ascorbic acid content variation in four plant species during processing. The biological material was represented by: green onion, spinach leaves, pear fruits (from vegetable farms around Suceava town and kiwi fruits (from supermarket. The ascorbic acid content was determined through a method based on reduction (by the ascorbic acid of 2.6-Dichlorphenol-indophenol to the corresponding leucoderivate. Through grinding and one hour exposure to air at 20-22°C, the largest reduction in ascorbic acid content was in pear fruits (50%, and the lowest one in spinach leaves (11.7%. By means of thermal processing (boiling the ascorbic acid content of the analyzed species has changed in different proportions. Thus, as compared to fresh samples, in boiled ones the vitamin C content has decreasedmost in pear fruits (by 52.6% and least in spinach leaves (by 38.5%. Under the same conditions, in green onion samplethe ascorbic acid mean content has increased by 10.8%, compared to fresh sample. In the fruit species, under thermal processing conditions, the ascorbic acid mean content was different as against heat-unprocessed samples. Thus, at kiwi fruits both in samples poached with sugar and without sugar, the total content of ascorbic acid (from product and boiling liquid was superior to the heat-unprocessed samples. In contrast, at pear fruits, under the same experimental conditions, the total content of ascorbic acid was lower than in heat-unprocessed samples.

  16. Improvement Of Salt Tolerance In Some Varieties Of Rice By Ascorbic Acid Application

    Directory of Open Access Journals (Sweden)

    Wan Arfiani Barus

    2015-05-01

    Full Text Available ABSTRACT Salinity stress is one of the serious abiotic stress and lead to reduced productivity and plant growth. The effect of salinity stress and its interaction with ascorbic acid was investigated on some morphological traits. Ascorbate is a strong antioxidant which has remarkable biological effects on plants growth including an improvement in plants tolerance under salinity stress conditions. The purpose of this study was to determine the effect of ascorbic acid application to improve salt tolerance of rice on saline soil. This research was down as a factorial based on randomized block design with 3 replications. In this research were tested eight varieties of Rice Ciherang V1 IR 64 V2 Lambur V4 Batanghari V5 Banyuasin V6 IR 42 V8 Inpara 10 V9 and Margasari V10 and Ascorbic Acid is applied at concentrations of 0 A0 500 ppm A1 1000 ppm A2 and 1500 ppm A3. Ascorbic acid is applied in 4 times with at the age of 15 35 55 and 75 days after sowing. All concentrations of ascorbic acid generally has a positive effect on morphological characters. However the best response was found at 1500 ppm A3 concentration of ascorbic acid on Banyuasin variety.

  17. Optical properties of chitosan in aqueous solution of L- and D-ascorbic acids

    Science.gov (United States)

    Malinkina, Olga N.; Shipovskaya, Anna B.; Kazmicheva, Olga F.

    2016-04-01

    The optical properties of aqueous chitosan solutions in L- and D-ascorbic acids were studied by optical rotatory dispersion and spectrophotometry. The specific optical rotation [α] of all chitosan solutions tested was positive, in contrast to aqueous solutions of the ascorbic acid enantiomers, which exhibit an inverse relationship of [α] values. Significant differences in the absolute values of [α] of the chitosan solutions at polymer-acid ratios exceeding the equimolar one were found.

  18. Analysis of Gastric Juice in Acid Peptic Diseases

    OpenAIRE

    Prasad V. Khodke , , ,; Z. G. Badade; N. L. Vyas

    2015-01-01

    Background: Peptic ulcer disease is an imbalance between offensive and defensive gastric factors. A bacterium called Helicobacter pylori has been considered a major causative agent for gastric and duodenal ulcers. This is a major cause of mortality in developing countries. Aims and Objectives:The aim of this study was to assess the biochemical parameters in gastric juice of acid peptic disease patients (Study Group) and normal healthy individuals (Control Group) in ...

  19. Iron prevents ascorbic acid (vitamin C) induced hydrogen peroxide accumulation in copper contaminated drinking water.

    Science.gov (United States)

    Jansson, Patric J; Lindqvist, Christer; Nordström, Tommy

    2005-11-01

    Ascorbic acid (vitamin C) induced hydrogen peroxide (H(2)O(2)) formation was measured in household drinking water and metal supplemented Milli-Q water by using the FOX assay. Here we show that ascorbic acid readily induces H(2)O(2) formation in Cu(II) supplemented Milli-Q water and poorly buffered household drinking water. In contrast to Cu(II), iron was not capable to support ascorbic acid induced H(2)O(2) formation during acidic conditions (pH: 3.5-5). In 12 out of the 48 drinking water samples incubated with 2 mM ascorbic acid, the H(2)O(2) concentration exceeded 400 microM. However, when trace amounts of Fe(III) (0.2 mg/l) was present during incubation, the ascorbic acid/Cu(II)-induced H(2)O(2) accumulation was totally blocked. Of the other common divalent or trivalent metal ions tested, that are normally present in drinking water (calcium, magnesium, zinc, cobalt, manganese or aluminum), only calcium and magnesium displayed a modest inhibitory activity on the ascorbic acid/Cu(II)-induced H(2)O(2) formation. Oxalic acid, one of the degradation products from ascorbic acid, was confirmed to actively participate in the iron induced degradation of H(2)O(2). Ascorbic acid/Cu(II)-induced H(2)O(2) formation during acidic conditions, as demonstrated here in poorly buffered drinking water, could be of importance in host defense against bacterial infections. In addition, our findings might explain the mechanism for the protective effect of iron against vitamin C induced cell toxicity.

  20. Leguminose green juice as an efficient nutrient for l(+)-lactic acid production.

    Science.gov (United States)

    Dietz, Donna; Schneider, Roland; Papendiek, Franka; Venus, Joachim

    2016-10-20

    Lactic acid is one of the most important building blocks for the production of bioplastic. Many investigations have been conducted to reduce the lactic acid production costs. In this work, the focus was put on the application of legume pressed juice or green juice as nutrient source. The pressed juice was utilized directly without prior pre-treatment and sterilization. Using two different alfalfa green juices and a clover green juice from two different harvest years as sole nutrients, non-sterile fermentations were performed at 52°C and pH 6.0 with a thermotolerant strain Bacillus coagulans AT107. The results showed that alfalfa green juices generally were more suitable for high lactic acid production than clover green juices, presumably due to the higher nitrogen content. A final titer of 98.8g/L after 30h with l(+)-lactic acid purity of >99% was obtained.

  1. Low temperature storage affects the ascorbic acid metabolism of cherry tomato fruits.

    Science.gov (United States)

    Tsaniklidis, Georgios; Delis, Costas; Nikoloudakis, Nikolaos; Katinakis, Panagiotis; Aivalakis, Georgios

    2014-11-01

    Tomato fruits are an important source of l-Ascorbic acid, which is an essential compound of human diet. The effect of the widespread practice of cold storing (5-10 °C) tomato fruits was monitored to determine its impact on the concentration and redox status of l-Ascorbic acid. Total l-Ascorbic acid levels were well maintained in both attached fruits and cold treated fruits, while in other treatments its levels were considerably reduced. However, low temperature storage conditions enhanced the expression of most genes coding for enzymes involved in l-Ascorbic acid biosynthesis and redox reactions. The findings suggest that the transcriptional up-regulation under chilling stress conditions of most genes coding for l-Ascorbic acid biosynthetic genes galactono-1,4-lactone dehydrogenase, GDP-d-mannose 3,5-epimerase but also for the isoenzymes of ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase enzyme, glutathione reductase that are strongly correlated to the l-Ascorbic redox status. Moreover, fruits stored at 10 °C exhibited higher levels of transcript accumulation of MDHAR2, DHAR1, DHAR2, GR1 and GR2 genes, pointing to a better ability to manage chilling stress in comparison to fruits stored at 5 °C.

  2. Ascorbic acid against reperfusion injury in human renal transplantation.

    Science.gov (United States)

    Norio, Karri; Wikström, Mårten; Salmela, Kaija; Kyllönen, Lauri; Lindgren, Leena

    2003-08-01

    The cadaveric renal graft is exposed to ischaemic injury during preservation and to oxidative damage during reperfusion. Both these mechanisms are known to cause cell damage, which may impair graft function. Reperfusion injury (RPI) is mediated by reactive oxygen species (ROS). Ascorbic acid (AA) is a potent physiological extracellular scavenger of ROS. We perfused 31 renal grafts immediately before implantation with a solution of Euro-Collins containing 0.5 mg/ml of AA to diminish RPI. From every donor, the contralateral kidney served as a control. The control grafts were perfused with the same perfusion as those of the AA group, only without the AA substitution. We assessed the effect of AA by recording serum creatinine, creatinine clearance, initial graft function and early rejections. The incidence of delayed graft function (DGF) was 32% in the AA group, and 29% in the control group. Other parameters were also similar in both groups, except for the length of DGF, which showed a trend towards a shorter duration in the AA group. The pre-operative systemic AA concentration was significantly ( P=0.01) lower in the haemodialysis patients than in those on peritoneal dialysis. In conclusion, this clinical study could not demonstrate significant benefits of AA in renal transplantation.

  3. Role of ascorbic acid against pathogenesis in plants

    Directory of Open Access Journals (Sweden)

    Taqi Ahmed Khan

    2011-09-01

    Full Text Available Plants vary considerably in their physiological response to various kinds of environmental stress. To prevent damage caused by pathogenic attack and to acclimate to change in their environment, plants have evolved direct and indirect mechanism for sensing and responding to pathogenic stimuli. Ascorbic acid (AA is found in all eukaryotes including animals and plants and lack completely in prokaryotes except cyanobactaria, have been reported to have a small amount. AA has now gained significant place in plant science, mainly due to its properties (antioxidant and cellular reductant etc., and multifunctional roles in plant growth, development, and regulation of remarkable spectrum of plant cellular mechanisms against environmental stresses. As it is evident from the present review, recent progress on AA potentiality in tolerance of plants to pathogenic attack has been impressive to a greater extent. AA produced in plants as indirect response against pathogenic attack at different sites in plants and its intertwined network cause changes in nuclear gene expression via retrograde signaling pathways, or even into systemic responses, all of which are associated with pathogenic resistance. Indeed, AA plays an important role in resistance to pathogenesis.

  4. Antidepressant-like effects of ascorbic acid and ketamine involve modulation of GABAA and GABAB receptors.

    Science.gov (United States)

    Rosa, Priscila B; Neis, Vivian B; Ribeiro, Camille M; Moretti, Morgana; Rodrigues, Ana Lúcia S

    2016-10-01

    It has been suggested that dysregulation of γ-aminobutyric acid (GABA)-mediated neurotransmission is involved in the etiology of major depressive disorder and in the action of the fast-acting antidepressant ketamine. Considering that recent evidence has suggested that ascorbic acid may exert an antidepressant-like effect through mechanisms similar to ketamine, this study evaluated the involvement of GABAA and GABAB receptors in the antidepressant-like effect of ascorbic acid, comparing the results with those obtained with ketamine. To investigate the involvement of GABAA in the antidepressant-like effect of ascorbic acid and ketamine in the tail suspension test (TST), mice were treated with a sub-effective dose of ascorbic acid (0.1mg/kg, po), ketamine (0.1mg/kg, ip) or vehicle and 30minutes later, a sub-effective dose of muscimol (0.1mg/kg, ip, GABAA receptor agonist) or vehicle was administered. In another set of experiments, mice were treated with ascorbic acid (1mg/kg, po, active dose in the TST) or vehicle and 30minutes later, baclofen (1mg/kg, ip, GABAB receptor agonist) was administered. A similar experimental protocol was performed with ketamine (1mg/kg, ip). The administration of muscimol combined with ascorbic acid or ketamine produced a synergistic antidepressant-like effect in the TST. Moreover, the antidepressant-like effects of ascorbic acid and ketamine were abolished by baclofen. There was no alteration in spontaneous locomotion in any experimental group. Results indicate that the anti-immobility effect of ascorbic acid and ketamine in TST may involve an activation of GABAA receptors and a possible inhibition of GABAB receptors. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  5. L-Ascorbic Acid Microencapsulated with Polyacylglycerol Monostearate for Milk Fortification

    National Research Council Canada - National Science Library

    LEE, Jun-Beum; AHN, Joungjwa; LEE, Jonghwi; KWAK, Hae-Soo

    2004-01-01

    ...% up to 5 d of storage. The TBA value was the lowest in the milk sample with added encapsulated iron and unencapsulated L-ascorbic acid up to 5 d of storage in comparison with the other treated samples...

  6. Study of Ascorbic Acid as Iron(III Reducing Agent for Spectrophotometric Iron Speciation

    Directory of Open Access Journals (Sweden)

    Antesar Elmagirbi

    2012-10-01

    Full Text Available The study of ascorbic acid as a reducing agent for iron(III has been investigated in order to obtain an alternative carcinogenic reducing agent, hydroxylamine, used in spectrophotometric standard method based on the formation of a red-orange complex of Fe(II-o-phenanthroline. The study was optimised with regards to ascorbic acid concentration as well as pH solution. The results showed that ascorbic acid showed maximum capacity as reducing agent of iron(III under concentration of 4.46.10-4 M and pH solution of 1-4.Under these conditions, ascorbic acid reduced iron(III proportionally and performed similarly to that of hydroxylamine.  The method gave result to linear calibration over the range of 0.2-2 mg/L withhigh accuracy of 97 % and relative standard deviation of less than 2 %. This method was successfully applied to assay iron speciation in water samples.

  7. Oxidation in fish oil enriched mayonnaise : Ascorbic acid and low pH increase oxidative deterioration

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte; Timm Heinrich, Maike; Meyer, Anne S.

    2001-01-01

    The effect of ascorbic acid (0-4000 ppm) and pH (3.8-6.2) on oxidation and levels of iron and copper in various fractions of mayonnaise enriched with 16% fish oil was investigated. Ascorbic acid induced release of iron from the assumed oil- water interface into the aqueous phase at all pH levels......, but this effect of ascorbic acid was strongest at low pH (pH 3.8- 4.2). Ascorbic acid generally promoted formation of volatile oxidation compounds and reduced the peroxide value in mayonnaises. Peroxide values and total volatiles generally increased with decreasing pH values, suggesting that low pH promoted...... due to the reduction of Fe3+ to Fe2+ that rapidly catalyzes lipid oxidation via lipid hydroperoxide decomposition at the oil-water interface in mayonnaise...

  8. Old Things New View: Ascorbic Acid Protects the Brain in Neurodegenerative Disorders

    Directory of Open Access Journals (Sweden)

    Adriana Covarrubias-Pinto

    2015-11-01

    Full Text Available Ascorbic acid is a key antioxidant of the Central Nervous System (CNS. Under brain activity, ascorbic acid is released from glial reservoirs to the synaptic cleft, where it is taken up by neurons. In neurons, ascorbic acid scavenges reactive oxygen species (ROS generated during synaptic activity and neuronal metabolism where it is then oxidized to dehydroascorbic acid and released into the extracellular space, where it can be recycled by astrocytes. Other intrinsic properties of ascorbic acid, beyond acting as an antioxidant, are important in its role as a key molecule of the CNS. Ascorbic acid can switch neuronal metabolism from glucose consumption to uptake and use of lactate as a metabolic substrate to sustain synaptic activity. Multiple evidence links oxidative stress with neurodegeneration, positioning redox imbalance and ROS as a cause of neurodegeneration. In this review, we focus on ascorbic acid homeostasis, its functions, how it is used by neurons and recycled to ensure antioxidant supply during synaptic activity and how this antioxidant is dysregulated in neurodegenerative disorders.

  9. Effect of ascorbic acid on the properties of ammonia caramel colorant additives and acrylamide formation.

    Science.gov (United States)

    Chen, Hongxing; Gu, Zhengbiao

    2014-09-01

    Ammonia caramels are among the most widely used colorant additives in the food industry. They are commonly prepared through the Maillard reaction and caramelization of mixtures of reducing sugars with ammonia or ammonium salts. Antioxidants are known to inhibit acrylamide formation during the Maillard reaction, and they may affect the properties of the ammonia caramel products. Thus, the objective of this study was to investigate the effect of the antioxidant ascorbic acid on the properties of ammonia caramel. A mixture of glucose and ammonia was allowed to react at 120 °C for 60 min in the presence of ascorbic acid at final concentrations of 0 to 0.08 M. The ammonia caramels obtained from these reactions were all positively charged. As the concentration of ascorbic acid increased, the color intensity of the ammonia caramel showed a decreasing trend, while the intensity of the fluorescence and total amount of pyrazines in the volatiles showed a tendency to increase. The addition of ascorbic acid did not result in obvious changes in the UV-visible spectra of the ammonia caramels and the types of pyrazines in the volatiles were also unchanged. It is noteworthy that the addition of 0.02 to 0.08 M ascorbic acid did reduce the formation of the by-product acrylamide, a harmful substance in food. When the concentration of ascorbic acid added reached 0.04 M, the content of acrylamide in the ammonia caramel was 20.53 μg/L, which was approximately 44% lower than that without ascorbic acid. As a result, ascorbic acid can be considered to improve the quality and safety of ammonia caramels.

  10. Cu2+-Catalyzed Oscillatory Oxidation of Ascorbic Acid by O2 Flow

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A novel heterogeneous oscillator, the Cu2+-catalyzed oscillatory oxidation of ascorbic acid (Vitamin C) in aqueous solution by O2 flow was reported. Both the potential oscillations on Pt-electrode corresponding to [Cu2+] and the absorbance oscillations at l=260 nm corresponding to [ascorbic acid] were observed. Oscillations in the completely homogeneous system were also observed. Effects of several factors on the oscillations were investigated.

  11. Evaluation of mineral elements and ascorbic acid contents in fruits of some wild plants.

    Science.gov (United States)

    Eromosele, I C; Eromosele, C O; Kuzhkuzha, D M

    1991-04-01

    The fruits of some wild plants were examined for their contents of mineral elements and ascorbic acid. High levels of ascorbic acid were found in fruits of Sclerocarya birrea (403.3 mg/100 g) and Adansonia digitata (337 mg/100 g). In nine of the fruits examined, the mineral contents (Ca, P) were comparable with average values found in common fruits. The iron contents were however 2-5 times higher than the values for common fruits.

  12. Measuring Vitamin C Content of Commercial Orange Juice Using a Pencil Lead Electrode

    Science.gov (United States)

    King, David; Friend, Jeffrey; Kariuki, James

    2010-01-01

    A pencil lead successfully served as an electrode for the determination of ascorbic acid in commercial orange juice. Cyclic voltammetry was used as an electrochemical probe to measure the current produced from the oxidation of ascorbic acid with a variety of electrodes. The data demonstrate that the less expensive pencil lead electrode gives…

  13. Measuring Vitamin C Content of Commercial Orange Juice Using a Pencil Lead Electrode

    Science.gov (United States)

    King, David; Friend, Jeffrey; Kariuki, James

    2010-01-01

    A pencil lead successfully served as an electrode for the determination of ascorbic acid in commercial orange juice. Cyclic voltammetry was used as an electrochemical probe to measure the current produced from the oxidation of ascorbic acid with a variety of electrodes. The data demonstrate that the less expensive pencil lead electrode gives…

  14. The influence of ascorbic acid on in vitro maturation of canine oocytes

    Directory of Open Access Journals (Sweden)

    Anamaria Jeni Pernes

    2016-11-01

    It is known that L-ascorbic acid (vitamin C can modulate many biochemical processes intracellularly or extracellularly as antioxidant. The aim of the present study was to examine the effects of media supplementation with ascorbic acid on canine oocyte meiotic maturation, viability and the cumulus cell expansion. Various concentrations of ascorbic acid supplemented in in vitro maturation (IVM media were tested. Canine oocyte was exposed to different levels of ascorbic acid (0, 50, 150, 250, 500, 750µM. Cumulus expansion, meiotic maturation and degeneration of oocytes were assessed 72 h after in vitro culture. As results, on the group treated with 250µM ascorbic acid was a significant difference compared to the control group on nuclear maturation in stages metaphase I (MI and metaphase II (MII (26.98% vs. 6.00%. The groups treated with 50, 150, 250, 500µM had an increase in stage (GVBD, and a significant decrease of degenerate-undefined oocytes compared with the control (23.31%, 18.85%, 13.41% vs 40.80. Concentration 750µM had similar effect to that in the control group. The groups treated with 50, 150, 250, 500µM had an increase in meiosis resumption(GVBD, metaphase I (MI and metaphase II (MII with the best result in the group treated with 250 µM ascorbic acid.

  15. Flow injection-chemiluminescence determination of ascorbic acid based on luminol–ferricyanide–gold nanoparticles system

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Yong Ping, E-mail: dongyp@ahut.edu.cn [School of chemistry and chemical engineering, Anhui University of Technology, Maanshan, China, 243002 (China); Gao, Ting Ting; Chu, Xiang Feng; Chen, Jun [School of chemistry and chemical engineering, Anhui University of Technology, Maanshan, China, 243002 (China); Wang, Cheng Ming, E-mail: chmwang@ustc.edu.cn [Hefei National Laboratory for Physical Science at the Microscale, University of Science and Technology of China, Hefei, China, 230026 (China)

    2014-10-15

    A novel flow-injection chemiluminescence (CL) method for the determination of ascorbic acid (AA) is proposed, based upon its enhancing effect on the CL reaction of luminol with ferricyanide catalyzed by gold nanoparticles in alkaline solution. Different sizes gold nanoparticles exhibited different catalyzing effect towards luminol CL and 38 nm gold nanoparticles exhibited the best enhancing effect. Under the optimal experimental conditions, a linear relationship was obtained between the CL intensity and the concentration of ascorbic acid in the range of 1.0×10{sup −10}–1.0×10{sup −6} mol L{sup −1}. The detection limit was 2.0×10{sup –11} mol {sup −1} and the relative standard deviation for 1.0×10{sup −6} mol L{sup −1} ascorbic acid was 0.71% (n=10). This method has been successfully applied in the determination of ascorbic acid in several real samples. - Highlights: • Gold nanoparticles could enhance luminol–K{sub 3}Fe(CN){sub 6} CL signal. • 38 nm gold nanoparticles exhibited the best catalyzing effect. • Ascorbic acid could further enhance luminol–K{sub 3}Fe(CN){sub 6}–gold nanoparticles CL. • Ascorbic acid could be detected sensitively based on its enhancing effect.

  16. Effects of ascorbic acid on some physiological changes of pepino (Solanum muricatum Ait.) under chilling stress.

    Science.gov (United States)

    Sivaci, Aysel; Kaya, A; Duman, Sevcan

    2014-09-01

    In this study, the changes caused by chilling stress on some physiological parameters of pepino (Solanum muricatum Ait.) plant and the effects of ascorbic acid (100 mM) applied exogenously on these changes were examined. For this purpose, the photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophylls and carotenoids), ascorbic acid, total phenolic compounds, malondialdehyde and proline contents in leaves of pepino taken on 5th and 10th days were determined. As a result of chilling stress, it was found that while the photosynthetic pigments and proline contents decreased in pepino leaves, the ascorbic acid, total phenolic compounds and malondialdehyde contents increased. In plants which were subjected to pre-treatment of ascorbic acid on the 10th day of stress, ascorbic acid and proline contents increased while a decrease was observed in malondialdehyde content, compared to stress group without pre-treated. This study may be important for explaining resistance induced by treatment of exogenous ascorbic acid in pepino exposed to chilling stress.

  17. EFFECT OF ASCORBIC ACID ON ISCHEMIA-REPERFUSIONARRHYTHMIAS IN ISOLATED GUINEA PIG RIGHT VENTRICULARWALL

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To investigate the protective effect of ascorbic acid on myocardium from ischemia and reperfusion injury and its electrophysiological mechanism. Methods Using modified Ferrier's arrhythmia induced by ischemia and reperfusion injury in isolated guinea pig right ventricular wall. Results Ascorbic acid at 5, 10, 50 and 100μmol/L slightly decrease incidence of ischemia arrhythmia (P > 0. 05). In contrast, ascorbic acid at 10, 50 and 100μmol/L significantly reduced the incidence of arrhythmia during early reperfusion(2~12min) (P < 0. 01 or P < 0. 001). Ascorbic acid at 5~ 100μmol/L didn't reverse the abbrevating of APD of endocardium and epicardium and didn't affect the conduction time in endocardium (P > 0. 05). However, ascorbic acid abbreviated epicardial conduc tion time significantly (P < 0. 05 or P < 0. 01 or P < 0. 001 ). Conclusion The study suggests that ascorbic acid might exert antiarrhythmic effect via alleviating conduction abnormity to avoid transmural reentries during ischemia and early reperfusion.

  18. A study on degradation kinetics of ascorbic acid in amla (Phyllanthus emblica L.) during cooking.

    Science.gov (United States)

    Nisha, P; Singhal, Rekha S; Pandit, Aniruddha B

    2004-08-01

    The kinetics of ascorbic acid degradation in amla (Phyllanthus emblica L.) as well as in pure ascorbic acid solutions at initial concentrations present in amla over a temperature range of 50-120 degrees C (steady-state temperature) has been studied. The ascorbic acid degradation followed first-order reaction kinetics where the rate constant increased with an increase in temperature. The temperature dependence of degradation was adequately modeled by the Arrhenius equation. The activation energies were found to be 4.09 kcal/mole for amla and 4.49 kcal/mole for pure vitamin solution. The degradation kinetics of ascorbic acid was also evaluated in normal open pan cooking, pressure-cooking and a newly developed and patented fuel-efficient EcoCooker (unsteady state heating process). A mathematical model was developed using the steady-state kinetic parameters obtained to predict the losses of ascorbic acid from the time-temperature data of the unsteady state heating processing method. The results obtained indicate the ascorbic acid degradation is of a similar order of magnitude in all the methods of cooking.

  19. Oxidative stress and innate immunity status in chickens exposed to high dose of ascorbic acid.

    Science.gov (United States)

    Berzina, Nadezhda; Markovs, Jurijs; Dizhbite, Tatiana; Apsite, Mirdza; Vasilyeva, Svetlana; Basova, Nataliya; Smirnova, Galina; Isajevs, Sergejs

    2013-10-01

    The effects of high dose ascorbic acid (10 000 mg·kg(-1) in the diet) and the transition metal on the presence of oxidative stress in the internal organs of growing chicks, as well as on the innate immune system status, were investigated. Supplementation with a high dose of ascorbic acid had pro-inflammatory effects on the intestinal mucosa, and lysozyme levels were decreased significantly in all organs studied. High-dose ascorbic acid caused an imbalance between prooxidative and antioxidative activities and was associated with the generation of semiquinone radicals. We observed that ascorbic acid increased iron and cadmium absorption. When a high dose of ascorbic acid was applied, elevated kidney and intestinal mucosa iron concentrations were observed. The amount of free malondialdehyde in the above organs has increased as well. These data have important implications for the mechanism of the oxidative stress development under the influence of high dose of ascorbic acid, indicating the importance of the side reactions of the mitochondrial electron transport chain with the formation of semiquinone radicals and the role of transition metals in this process.

  20. Development of a miniature silicon wafer fuel cell using L-ascorbic acid as fuel

    Institute of Scientific and Technical Information of China (English)

    Jian WO; Zhi-yong XIAO; Yi-bin YING; Philip C.H. CHAN

    2008-01-01

    In the current studies a miniature silicon wafer fuel cell (FC) using L-ascorbic acid as fuel was developed, The cell employs L-ascorbic acid and air as reactants and a thin polymer electrolyte as a separator. Inductively coupled plasma (ICP) silicon etching was employed to fabricate high aspect-ratio columns on the silicon substrate to increase the surface area. A thin platinum layer deposited directly on the silicon surface by the sputtering was used as the catalyst layer for L-ascorbic acid electro-oxidation.Cyclic voltammetry shows that the oxidation of L-ascorbic acid on the sputtered platinum layer is irreversible and that the onset potentials for the oxidation of L-ascorbic acid are from 0.27 V to 0.35 V versus an Ag/AgCI reference electrode. It is found that at the room temperature, with 1 mol/L L-ascorbic acid/PBS (phosphate buffered solution) solution pumped to the anode at 1 ml/min flow rate and air spontaneously diffusing to the cathode as the oxidant, the maximum output power density of the cell was 1.95m W/cm2 at a current density of 10 mA/cm2.

  1. alpha-Lipoic acid and ascorbate prevent LDL oxidation and oxidant stress in endothelial cells.

    Science.gov (United States)

    Sabharwal, Anup K; May, James M

    2008-02-01

    Both alpha-lipoic acid (LA) and ascorbic acid (vitamin C) have been shown to improve endothelial dysfunction, a precursor of atherosclerosis. Since oxidant stress can cause endothelial dysfunction, we tested the interaction and efficacy of these antioxidants in preventing oxidant damage to lipids due to both intra- and extracellular oxidant stresses in EA.hy926 endothelial cells. LA spared intracellular ascorbate in culture and in response to an intracellular oxidant stress induced by the redox cycling agent menadione. Extracellular oxidant stress generated by incubating cells for 2 h in with 0.2 mg/ml LDL and 5 muM Cu2+ caused a time-dependent increase of the lipid peroxidation product malondialdehyde in both cells and LDL, preceded by rapid disappearance of; alpha-tocopherol in LDL. alpha-Lipoic acid at concentrations of 40-80 microM blunted these effects. Similarly, intracellular ascorbate concentrations of 1-2 mM also prevented Cu2+-induced lipid peroxidation in LDL and cells. Cu2+-dependent oxidation of LDL in the presence of ascorbate-loaded cells decreased intracellular ascorbate by 20%, but this decrease was not reversed by LA. Both LA and ascorbate protect endothelial cells and LDL from either intra- or extracellular oxidant stress, but that LA does not spare ascorbate in oxidatively stressed cells.

  2. Quantitative Determination of Citric and Ascorbic Acid in Powdered Drink Mixes

    Science.gov (United States)

    Sigmann, Samuella B.; Wheeler, Dale E.

    2004-01-01

    A procedure by which the reactions are used to quantitatively determine the amount of total acid, the amount of total ascorbic acid and the amount of citric acid in a given sample of powdered drink mix, are described. A safe, reliable and low-cost quantitative method to analyze consumer product for acid content is provided.

  3. Reaction of 5-aminosalicylic acid with peroxyl radicals: protection and recovery by ascorbic acid and amino acids.

    Science.gov (United States)

    López-Alarcón, Camilo; Rocco, Claudia; Lissi, Eduardo; Carrasco, Catalina; Squella, J Arturo; Nuñez-Vergara, Luis; Speisky, Hernan

    2005-10-01

    The aims of the study are to analyze the interaction between 5-aminosalicylic acid (5-ASA) and peroxyl radicals and to evaluate the effect of some endogenous compounds such as ascorbic acid and amino acids on the oxidation of 5-ASA induced by 2,2'-azo-bis(2-amidinopropane) dihydrochloride. The consumption and/or the recovery of 5-ASA (7.6 microM) exposed to a peroxyl radical source [2,2'-azo-bis(2-amidinopropane)] was followed by techniques such as spectrofluorescence, high-performance liquid chromatography, and differential pulse voltammetry. 5-Aminosalicylic acid was found to readily react with peroxyl radicals at micromolar concentrations and to protect c-Phycocyanin in a very similar fashion to that shown by Trolox. Exposure of 5-ASA to peroxyl radicals led to its oxidation into the corresponding quinone-imine. Disappearance of 5-ASA was prevented by tryptophan, cysteine, glutathione, and ascorbic acid. Furthermore, some of these compounds induced the partial (cysteine and glutathione) or total (ascorbic acid) recovery of 5-ASA when added after its almost total consumption. 5-Aminosalicylic acid is a very efficient peroxyl radical scavenger. The 5-ASA oxidation by peroxyl radicals was prevented by ascorbic acid, cysteine, and glutathione. In addition, 5-ASA can be regenerated by these endogenous compounds, which would be a valuable mechanism to preserve 5-ASA in tissues undergoing oxidative stress conditions.

  4. Transport of ascorbic acid and dehydroascorbic acid by pancreatic islet cells from neonatal rats

    DEFF Research Database (Denmark)

    Zhou, A; Farver, O; Thorn, N A

    1991-01-01

    Several amidated biologically active peptides such as pancreastatin, thyrotropin-releasing hormone, pancreatic polypeptide and amylin are produced in endocrine pancreatic tissue which contains the enzyme necessary for their final processing, i.e. peptidylglycine alpha-amidating mono-oxygenase (EC 1.......14.17.3). The enzyme needs ascorbic acid for activity as well as copper and molecular oxygen. The present work shows that pancreatic islet cells prepared from overnight cultures of isolated islets from 5-7-day-old rats accumulate 14C-labelled ascorbic acid by a Na(+)-dependent active transport mechanism which involves...... contained a fairly low concentration of iron but a high concentration of copper....

  5. Ascorbic acid in cancer chemoprevention: translational perspectives and efficacy.

    Science.gov (United States)

    Ullah, Mohammad F; Bhat, Showket H; Hussain, Eram; Abu-Duhier, Faisel; Ahmad, Aamir; Hadi, S M

    2012-12-01

    Chemoprevention, which is referred to as the use of nontoxic natural or synthetic chemicals to intervene in multistage carcinogenesis has since decades attracted a considerable interest in plant-derived chemical constituents often termed as "phytochemicals" or sometimes as "Nutraceuticals" in case they are derived from dietary sources. A comprehensive search of the literature show that such an interest in natural product pharmacology has surged in the last 25 years and particularly risen at exponential rates since the last one decade. Phytochemicals such as curcumin (from spice turmeric), resveratrol (from red wine) and genistein (from soy) share the major efforts as indicated by overwhelming publications, despite skepticism concerning their bioavailability. Ascorbic acid (AA), the popular anti-oxidant in fruits and vegetables, has even a longer historical perspective than these dietary agents as for more than 35 years; there had been lingering questions about the efficacy of AA in cancer therapy. The footprints of AA from "scurvy" to "cancer" though complex seems to carry potential provided the puzzle could be set right. The use of AA in cancer treatment has been debated extensively as evident from the literature but surprisingly the complementing early phase bench work on the mechanistic studies for anticancer action was rather retarded. Proposed mechanisms of action for AA in the prevention and treatment of cancer includes antioxidant as well as pro-oxidant properties, stimulation of the immune system, altering carcinogen metabolism, enhancement of collagen synthesis necessary for tumor encapsulation and interference with cancer cell signaling. The observation that the intravenous administration of AA enhances its bioavailability to the extent of deriving pharmacological benefits against cancer has in recent years partially supported the clinical plausibility (efficacy) of AA towards realizing its translational advantage. Here, we provide an overview of AA with

  6. Ascorbic acid administration produces an antidepressant-like effect: evidence for the involvement of monoaminergic neurotransmission.

    Science.gov (United States)

    Binfaré, Ricardo W; Rosa, Angelo O; Lobato, Kelly R; Santos, Adair R S; Rodrigues, Ana Lúcia S

    2009-04-30

    Ascorbic acid is highly concentrated in the brain, being considered as a neuromodulator. This study investigated the effect of ascorbic acid in the tail suspension test (TST) and in the forced swimming test (FST) in mice and the contribution of the monoaminergic system to its antidepressant-like effect. Moreover, the effects of fluoxetine, imipramine and bupropion in combination with ascorbic acid in the TST were investigated. Ascorbic acid (0.1-10 mg/kg, i.p., 1-10 mg/kg p.o. or 0.1 nmol/mice i.c.v.) produced an antidepressant-like effect in the TST, but not in the FST, without altering the locomotor activity. The effect of ascorbic acid (0.1 mg/kg, i.p.) in the TST was prevented by i.p. pre-treatment with NAN-190 (0.5 mg/kg), ketanserin (5 mg/kg), MDL72222 (0.1 mg/kg), prazosin (62.5 microg/kg), yohimbine (1 mg/kg), propranolol (2 mg/kg), haloperidol (0.2 mg/kg), sulpiride (50 mg/kg), but not with SCH23390 (0.05 mg/kg, s.c.). Additionally, ascorbic acid (1 mg/kg, p.o.) potentiated the effect of subeffective doses (p.o. route) of fluoxetine (1 mg/kg), imipramine (0.1 mg/kg), or bupropion (1 mg/kg) in the TST. The combined treatment of ascorbic acid with antidepressants produced no alteration in the locomotion in the open-field test. In conclusion, our results show that administration of ascorbic acid produces an antidepressant-like effect in TST, which is dependent on its interaction with the monoaminergic system. Moreover, ascorbic acid caused a synergistic antidepressant-like effect with conventional antidepressants. Therefore, the present findings warrant further studies to evaluate the therapeutical relevance of ascorbic acid for the treatment of depression and as a co-adjuvant treatment with antidepressants.

  7. Antimutagenic activity of cashew apple (Anacardium occidentale Sapindales, Anacardiaceae) fresh juice and processed juice (cajuína) against methyl methanesulfonate, 4-nitroquinoline N-oxide and benzo[a]pyrene

    OpenAIRE

    2008-01-01

    Cashew apple juice (CAJ), produced from the native Brazilian cashew tree (Anacardium occidentale), and has been reported to have antibacterial, antifungal, antitumor, antioxidant and antimutagenic properties. Both the fresh unprocessed juice and the processed juice (cajuína in Portuguese) has been shown to consist of a complex mixture containing high concentrations of anacardic and ascorbic acids plus several carotenoids, phenolic compounds and metals. We assessed both types of juice for thei...

  8. Ascorbic acid for the treatment of Charcot-Marie-Tooth disease.

    Science.gov (United States)

    Gess, Burkhard; Baets, Jonathan; De Jonghe, Peter; Reilly, Mary M; Pareyson, Davide; Young, Peter

    2015-12-11

    Charcot-Marie-Tooth disease (CMT) comprises a large group of different forms of hereditary motor and sensory neuropathy. The molecular basis of several CMT subtypes has been clarified during the last 20 years. Since slowly progressive muscle weakness and sensory disturbances are the main features of these syndromes, treatments aim to improve motor impairment and sensory disturbances to improve abilities. Pharmacological treatment trials in CMT are rare. This review was derived from a Cochrane review, Treatment for Charcot Marie Tooth disease, which will be updated via this review and a forthcoming title, Treatments other than ascorbic acid for Charcot-Marie-Tooth disease. To assess the effects of ascorbic acid (vitamin C) treatment for CMT. On 21 September 2015, we searched the Cochrane Neuromuscular Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and LILACS for randomised controlled trials (RCTs) of treatment for CMT. We also checked clinical trials registries for ongoing studies. We included RCTs and quasi-RCTs of any ascorbic acid treatment for people with CMT. Where a study aimed to evaluate the treatment of general neuromuscular symptoms of people with peripheral neuropathy including CMT, we included the study if we were able to identify the effect of treatment in the CMT group. We did not include observational studies or case reports of ascorbic acid treatment in people with CMT. Two review authors (BG and JB) independently extracted the data and assessed study quality. Six RCTs compared the effect of oral ascorbic acid (1 to 4 grams) and placebo treatment in CMT1A. In five trials involving adults with CMT1A, a total of 622 participants received ascorbic acid or placebo. Trials were largely at low risk of bias. There is high-quality evidence that ascorbic acid does not improve the course of CMT1A in adults as measured by the CMT neuropathy score (0 to 36 scale) at 12 months (mean difference (MD) -0.37; 95

  9. Analysis of Gastric Juice in Acid Peptic Diseases

    Directory of Open Access Journals (Sweden)

    Prasad V. Khodke , , ,

    2015-01-01

    Full Text Available Background: Peptic ulcer disease is an imbalance between offensive and defensive gastric factors. A bacterium called Helicobacter pylori has been considered a major causative agent for gastric and duodenal ulcers. This is a major cause of mortality in developing countries. Aims and Objectives:The aim of this study was to assess the biochemical parameters in gastric juice of acid peptic disease patients (Study Group and normal healthy individuals (Control Group in humans. Material and Methods: A total of 70 patients suffering peptic ulcer disease with H. pylori infection and 15 non-infected individuals were chosen as control group. Results: We observed an increased significant level (p<0.05 in pH, b-glucuronidase activity, malondialdehyde (MDA and superoxide dismutase (SOD as well as catalase(CAT levels in gastric juice and decrease significant level (p<0.05 in pepsin activity, urea, mucin and nitric oxide level. Conclusion: The present study showed variations in levels of MDA, b-glucuronidase, SOD, CAT activities, pepsin, mucin urea and nitric oxide. Therefore these parameters can be used as additional parameters for diagnosis and prognosis of acid peptic diseases. These can be used by clinicians to adopt treatment strategies in betterment of acid peptic disease patients.

  10. Plasma Ascorbic Acid, A Priori Diet Quality Score, and Incident Hypertension: A Prospective Cohort Study.

    Science.gov (United States)

    Buijsse, Brian; Jacobs, David R; Steffen, Lyn M; Kromhout, Daan; Gross, Myron D

    2015-01-01

    Vitamin C may reduce risk of hypertension, either in itself or by marking a healthy diet pattern. We assessed whether plasma ascorbic acid and the a priori diet quality score relate to incident hypertension and whether they explain each other's predictive abilities. Data were from 2884 black and white adults (43% black, mean age 35 years) initially hypertension-free in the Coronary Artery Risk Development in Young Adults Study (study year 10, 1995-1996). Plasma ascorbic acid was assessed at year 10 and the diet quality score at year 7. Eight-hundred-and-forty cases of hypertension were documented between years 10 and 25. After multiple adjustments, each 12-point (1 SD) higher diet quality score at year 7 related to mean 3.7 μmol/L (95% CI 2.9 to 4.6) higher plasma ascorbic acid at year 10. In separate multiple-adjusted Cox regression models, the hazard ratio of hypertension per 19.6-μmol/L (1 SD) higher ascorbic acid was 0.85 (95% CI 0.79-0.92) and per 12-points higher diet score 0.86 (95% CI 0.79-0.94). These hazard ratios changed little with mutual adjustment of ascorbic acid and diet quality score for each other, or when adjusted for anthropometric variables, diabetes, and systolic blood pressure at year 10. Intake of dietary vitamin C and several food groups high in vitamin C content were inversely related to hypertension, whereas supplemental vitamin C was not. In conclusion, plasma ascorbic acid and the a priori diet quality score independently predict hypertension. This suggests that hypertension risk is reduced by improving overall diet quality and/or vitamin C status. The inverse association seen for dietary but not for supplemental vitamin C suggests that vitamin C status is preferably improved by eating foods rich in vitamin C, in addition to not smoking and other dietary habits that prevent ascorbic acid from depletion.

  11. Effects of Ascorbic Acid, Phytic Acid and Tannic Acid on Iron Bioavailability from Reconstituted Ferritin Measured by an In Vitro Digestion/Caco-2 Cell Model

    Science.gov (United States)

    The effects of ascorbic acid, phytate and tannic acid on Fe bioavailability from Fe supplied as ferritin was compared to FeSO4 using an in vitro digestion/Caco-2 cell model. Horse spleen ferritin (HSF) was chemically reconstituted into a plant-type ferritin (P-HSF). In the presence of ascorbic acid...

  12. Ascorbic acid supplementation does not improve efficacy of meso-dimercaptosuccinic acid treatment in lead-exposed suckling rats.

    Science.gov (United States)

    Varnai, Veda Marija; Piasek, Martina; Blanusa, Maja; Juresa, Dijana; Sarić, Marija; Kostial, Krista

    2003-10-01

    It was suggested that ascorbic acid as a natural chelating agent can influence lead toxicokinetics and improve chelating properties of dimercaptosuccinic acid (DMSA) in adult rats. In this paper potential benefits of ascorbic acid supplementation, alone or combined with DMSA, in decreasing lead retention in suckling rats were evaluated. Such data in young mammals are not available. L-Ascorbic acid (daily dose 650 mg/kg b.wt.) and/or DMSA (daily dose 91 mg/kg b.wt.) were administered orally to suckling Wistar rats either during ongoing 8-day oral lead exposure (as acetate; daily dose 2 mg lead/kg b.wt.) or after 3-day lead exposure (total dose 12 mg lead/kg b.wt.). Lead concentrations were analysed in the carcass (skeleton), liver, kidneys and brain by atomic absorption spectrometry. By ascorbic acid supplementation lead retention was not reduced under either lead exposure condition. Lead concentration was even increased in the carcass. Treatment with DMSA under both exposure conditions significantly reduced lead in all analysed tissues. Combined treatment with ascorbic acid and DMSA during ongoing lead exposure was substantially less effective than DMSA treatment alone, and did not affect DMSA efficacy when administered after lead exposure. It was concluded that ascorbic acid administered either during or after lead exposure in suckling rats has no beneficial effect on either lead retention or DMSA chelation effectiveness.

  13. Simultaneous determination of rutin and ascorbic acid mixture in their pure forms and combined dosage form

    Science.gov (United States)

    Attia, Tamer Z.

    2016-12-01

    A simple, rapid, sensitive and selective high performance liquid chromatographic (HPLC) method with ultraviolet detection has been developed for simultaneous determination of ascorbic acid and rutin in pure forms and pharmaceutical dosage form. HPLC separation was performed on Phenomenex C18 analytical column with 0.1% v/v acetic acid in water and acetonitrile (75:25, v/v), as mobile phase. The separation was done at ambient temperature with flow rate of 1 mL·min- 1 in isocratic mode. HPLC measurements were carried out using ultraviolet detection wavelength at 257 nm. The average retention times were 2.72 and 7.00 min for ascorbic acid and rutin, respectively. The calibration plots were constructed over the concentration range of 5.0-30.0 for ascorbic acid and 10.0-60.0 μg·mL- 1 for rutin. The limits of detection were 1.06 and 1.89 μg·mL- 1 and limits of quantification were 3.54 and 6.31 μg·mL- 1 for ascorbic acid and rutin, respectively. The proposed HPLC-UV method was successfully applied for determination of ascorbic acid in its tablets and for simultaneous determination of the studied drugs in their laboratory prepared mixtures and in pharmaceutical formulation. Statistical comparisons of the results with the reference method show an excellent agreement and indicate no significant difference in respect to accuracy and precision.

  14. A Multiwall Carbon Nanotube-chitosan Modified Electrode for Selective Detection of Dopamine in the Presence of Ascorbic Acid

    Institute of Scientific and Technical Information of China (English)

    Ling Yan JIANG; Chuan Yin LIU; Li Ping JIANG; Guang Han LU

    2005-01-01

    A novel multiwall carbon nanotube-chitosan modified electrode has been prepared.The modified electrode resolves the overlapping voltammetric response of dopamine and ascorbic acid into two well-defined peak by 212 mY. The mechanism of discrimination of dopamine from ascorbic acid is discussed. Dopamine can be determined selectively with the carbon nanotube-chitosan modified electrode. The electrode shows good sensitivity, selectivity and stability.keywords: Nanotube-chitosan modified electrode, dopamine, ascorbic acid.

  15. Nanosized SnO2 Particles Dispersed on a Graphite Electrode for Selective Detection of Dopamine and Ascorbic Acid

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A novel nano-SnO2/graphite electrode has been prepared via polishing procedure to produce active and stable surface. The modified electrode resolves the overlapping voltammetric response of dopamine and ascorbic acid into two well-defined peaks by 230 mV. The mechanism of discrimination of dopamine from ascorbic acid is discussed. Dopamine and ascorbic acid can be determined simultaneously with the modified electrode. The electrode shows good sensitivity, selectivity and stability.

  16. The comparison of techniques and methods for L-ascorbic acid determination in the fruits

    Directory of Open Access Journals (Sweden)

    Cvetković Biljana R.

    2012-01-01

    Full Text Available Vitamin C is an essential vitamin for human nutrition; with the L-ascorbic acid (AA being the active form of vitamin C. Hence, determination of the L-ascorbic acid in the natural and processed foods is very important. In the past, plenty of methods based on the reversible redox reaction of AA oxidation/DHA reduction were developed. Because of L-ascorbic acid instability in aqueous solutions, it is useful to analyze various types of extraction. The aim of this study is to compare three different methods and three different extractants for the L-ascorbic acid determination. Fruits (kiwi, lemon, orange, and grapefruit were purchased from a local market. The L-ascorbic acid in these four samples was determined by the three different methods: the AOAC, the HPLC method with three different types of extractions, and the colorimetric method using ascorbate-oxidase. For the HPLC measurements, one part of the fruits was extracted with distilled water, the second with potassium hydrogen phosphate, and the third with 3% meta-phosphoric acid (MPA in 8% acetic acid. The HPLC measurements of each sample were repeated three times, the AOAC titration was repeated five times, and in the calorimetric method three measurements were performed. The results were statistically evaluated related to sample basis. Statistical analysis shows that there is a significant difference between the results for all three methods of extraction for all samples, except for the grapefruit sample where no significant difference was observed between the results obtained after the buffer extraction (E2 and the metaphosphoric acid in acetic acid extraction (E3. Discriminative analysis for the HPLC determinations proves that there is a clear difference and defined border between the samples in relation to the methods of extraction during the HPLC determination.

  17. Ascorbic acid protects lipids in human plasma and low-density lipoprotein against oxidative damage

    Energy Technology Data Exchange (ETDEWEB)

    Frei, B. (Department of Nutrition, Harvard School of Public Health, Boston, MA (Unites States))

    1991-12-01

    The authors exposed human blood plasma and low-density lipoprotein (LDL) to many different oxidative challenges and followed the temporal consumption of endogenous antioxidants in relation to the initiation of oxidative damage. Under all types of oxidizing conditions, ascorbic acid completely protects lipids in plasma and LDL against detectable peroxidative damage as assessed by a specific and highly sensitive assay for lipid peroxidation. Ascorbic acid proved to be superior to the other water-soluble plasma antioxidants bilirubin, uric acid, and protein thiols as well as to the lipoprotein-associated antioxidants alpha-tocopherol, ubiquinol-10, lycopene, and beta-carotene. Although these antioxidants can lower the rate of detectable lipid peroxidation, they are not able to prevent its initiation. Only ascorbic acid is reactive enough to effectively intercept oxidants in the aqueous phase before they can attack and cause detectable oxidative damage to lipids.

  18. Mitochondrial ascorbic acid transport is mediated by a low-affinity form of the sodium-coupled ascorbic acid transporter-2.

    Science.gov (United States)

    Muñoz-Montesino, Carola; Roa, Francisco J; Peña, Eduardo; González, Mauricio; Sotomayor, Kirsty; Inostroza, Eveling; Muñoz, Carolina A; González, Iván; Maldonado, Mafalda; Soliz, Carlos; Reyes, Alejandro M; Vera, Juan Carlos; Rivas, Coralia I

    2014-05-01

    Despite the fundamental importance of the redox metabolism of mitochondria under normal and pathological conditions, our knowledge regarding the transport of vitamin C across mitochondrial membranes remains far from complete. We report here that human HEK-293 cells express a mitochondrial low-affinity ascorbic acid transporter that molecularly corresponds to SVCT2, a member of the sodium-coupled ascorbic acid transporter family 2. The transporter SVCT1 is absent from HEK-293 cells. Confocal colocalization experiments with anti-SVCT2 and anti-organelle protein markers revealed that most of the SVCT2 immunoreactivity was associated with mitochondria, with minor colocalization at the endoplasmic reticulum and very low immunoreactivity at the plasma membrane. Immunoblotting of proteins extracted from highly purified mitochondrial fractions confirmed that SVCT2 protein was associated with mitochondria, and transport analysis revealed a sigmoidal ascorbic acid concentration curve with an apparent ascorbic acid transport Km of 0.6mM. Use of SVCT2 siRNA for silencing SVCT2 expression produced a major decrease in mitochondrial SVCT2 immunoreactivity, and immunoblotting revealed decreased SVCT2 protein expression by approximately 75%. Most importantly, the decreased protein expression was accompanied by a concomitant decrease in the mitochondrial ascorbic acid transport rate. Further studies using HEK-293 cells overexpressing SVCT2 at the plasma membrane revealed that the altered kinetic properties of mitochondrial SVCT2 are due to the ionic intracellular microenvironment (low in sodium and high in potassium), with potassium acting as a concentration-dependent inhibitor of SVCT2. We discarded the participation of two glucose transporters previously described as mitochondrial dehydroascorbic acid transporters; GLUT1 is absent from mitochondria and GLUT10 is not expressed in HEK-293 cells. Overall, our data indicate that intracellular SVCT2 is localized in mitochondria, is

  19. Cytotoxicity of copper(II) complexes of N-salicylidene-L-glutamate: modulation by ascorbic acid.

    Science.gov (United States)

    Paulikova, H; Kadlecikova, E; Suchanova, M; Valkova, Z; Rauko, P; Hudecova, D; Valent, A

    2008-01-01

    Cytotoxic/cytostatic activity of N-salicylidene-L-glutamato diaqua copper(II) complex (CuC) against mice leukemia cells L1210 has been estimated and their bioactivity was enhanced by addition of ascorbic acid. The Cu-complex with isoquinoline ligand (IQ-CuC) had stronger cytostatic effect (IC50 =15.6 microM) than parental complex (CuC) and its cytotoxicity several times increased in the presence of 0.1 mM ascorbic acid (IC50 =1.0 microM). The cytotoxicity has been caused by oxidative stress, enhanced creation of TBARS has been confirmed, and formation of 2',7'-dichlorofluorescein from 2',7'- dichlorodihydrofluorescein has been observed, also. Some hallmarks of apoptotic/necrotic death of L1210 cells have been observed by fluorescent microscopy after dyeing of cell with propidium iodide and Hoechst 33342. In addition, it was confirmed that both complexes in the presence of ascorbic acid cleavaged of pDNA. Although these copper complexes were initially prepared as substances with antioxidant properties we have showed that combined treatment of L1210 cells with IQCuC and ascorbic acid induced strong oxidative stress and death of cells. Our results confirmed that physiological concentration of ascorbic acid increases the cytostatic/cytotoxic efficiency of N-salicylidene-L-glutamato diaqua copper(II) complexes.

  20. Oxidation in fish oil enriched mayonnaise : Ascorbic acid and low pH increase oxidative deterioration

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte; Timm Heinrich, Maike; Meyer, Anne S.

    2001-01-01

    oxidation. It is proposed that iron bridges between the egg yolk proteins low-density lipoproteins, lipovitellin, and phosvitin at the oil-water interface are broken at low pH values, whereby iron ions become accessible as oxidation initiators. In the presence of ascorbic acid, oxidation is further enhanced......The effect of ascorbic acid (0-4000 ppm) and pH (3.8-6.2) on oxidation and levels of iron and copper in various fractions of mayonnaise enriched with 16% fish oil was investigated. Ascorbic acid induced release of iron from the assumed oil- water interface into the aqueous phase at all pH levels......, but this effect of ascorbic acid was strongest at low pH (pH 3.8- 4.2). Ascorbic acid generally promoted formation of volatile oxidation compounds and reduced the peroxide value in mayonnaises. Peroxide values and total volatiles generally increased with decreasing pH values, suggesting that low pH promoted...

  1. The Effect of Ascorbic Acid on Mancozeb-Induced Toxicity in Rat Thymocytes.

    Science.gov (United States)

    Pavlovic, V; Cekic, S; Kamenov, B; Ciric, M; Krtinic, D

    2015-01-01

    Mancozeb, as a dithiocarbamate fungicide, has been found to exhibit toxicological manifestations in different cells, mainly by generation of free radicals which may alter antioxidant defence systems in cells. The effect of mancozeb on the cells of a primary lymphoid organ has not been studied. In the present study, the effects of mancozeb (0.2, 2 and 5 μg/ml) or mancozeb+ascorbic acid (100 μg/ml), or ascorbic acid alone or control medium alone on the levels of cell viability, apoptosis, intracellular reactive oxygen species production (ROS), mitochondrial membrane potential (MMP) and ATP levels in rat thymocytes were examined in vitro. Cells treated with mancozeb displayed a concentration-dependent increase of hypodiploid cells and ROS production followed by markedly decreased viability of the cells, MMP and ATP levels. Application of ascorbic acid significantly reduced cytotoxicity in cell cultures treated with 0.2 and 2 μg/ml of mancozeb, together with significantly decreased ROS levels and increased MMP and ATP levels. In cells treated with 5 μg/ml of mancozeb, ascorbic acid failed to reduce toxicity while simultaneously increasing the apoptosis rate of thymocytes. These results suggest that ROS plays a significant role in mancozeb-induced toxicity, through alteration of mitochondrial function. Ascorbic acid administration reduced the toxicity rate in cells treated with lower mancozeb concentrations, while it may have the ability to shift cells from necrosis to apoptosis in the presence of highest mancozeb concentrations.

  2. Oxidation in fish oil enriched mayonnaise: ascorbic acid and low pH increase oxidative deterioration.

    Science.gov (United States)

    Jacobsen, C; Timm, M; Meyer, A S

    2001-08-01

    The effect of ascorbic acid (0-4000 ppm) and pH (3.8-6.2) on oxidation and levels of iron and copper in various fractions of mayonnaise enriched with 16% fish oil was investigated. Ascorbic acid induced release of iron from the assumed oil-water interface into the aqueous phase at all pH levels, but this effect of ascorbic acid was strongest at low pH (pH 3.8-4.2). Ascorbic acid generally promoted formation of volatile oxidation compounds and reduced the peroxide value in mayonnaises. Peroxide values and total volatiles generally increased with decreasing pH values, suggesting that low pH promoted oxidation. It is proposed that iron bridges between the egg yolk proteins low-density lipoproteins, lipovitellin, and phosvitin at the oil-water interface are broken at low pH values, whereby iron ions become accessible as oxidation initiators. In the presence of ascorbic acid, oxidation is further enhanced due to the reduction of Fe(3+) to Fe(2+) that rapidly catalyzes lipid oxidation via lipid hydroperoxide decomposition at the oil-water interface in mayonnaise.

  3. Luminescence quenching of porous silicon nanoparticles in presence of ascorbic acid

    Energy Technology Data Exchange (ETDEWEB)

    La Ferrara, Vera; Fiorentino, Giuseppe; Rametta, Gabriella; Di Francia, Girolamo [ENEA Research Centre, Portici (Italy)

    2012-04-15

    In this work, the effect of ascorbic acid on luminescence of porous silicon nanoparticles is studied. Porous nanoparticles with a multi-sized distribution are produced from a porous silicon free standing film and filtered through a 450 nm membrane. The highly luminescent and water-soluble nanoparticles are dispersed in deionized water. The stability of photoluminescence signal and the dimensions of porous silicon nanoparticles are characterized before adding ascorbic acid into the porous nanoparticles solution. The increasing of photoluminescence, before stabilization, has been correlated to oxidation of nanoparticles in water, evaluated by the technique of Attenuated Total Reflection. Once the nanoparticle photoluminescence signal is stabilized, ascorbic acid is loaded into the solution and its presence and real absorption onto the porous silicon nanoparticles are evaluated from their emission quenching. The quenching of photoluminescence is studied with different concentrations of ascorbic acid by Stern-Volmer plot for confirming the quenching law. This study shows that luminescence quenching of porous nanoparticles could be used for determining the presence of ascorbic acid in a solution. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Correction of anemia and iron deficiency in vegetarians by administration of ascorbic acid.

    Science.gov (United States)

    Sharma, D C; Mathur, R

    1995-10-01

    Twenty-eight strict vegetarians were given 500 mg ascorbic acid twice daily after lunch and dinner for two months. Hemoglobin and certain iron status parameters were measured before and after the treatment. Ascorbate treatment increased mean hemoglobin by 8%, serum iron by 17% and transferrin saturation by 23% and decreased total iron binding capacity by 7%. All these changes were statistically significant. The rise in serum ferritin was 12%. The serum protein or copper level did not indicate their dietary deficiency, while initial serum ascorbate level were low which rose by 60% on therapy. It is concluded that ascorbate supplementation is a better method of improving hematologic and iron status than iron salt administration.

  5. Haloacetic acids content of fruit juices and soft drinks.

    Science.gov (United States)

    Cardador, María José; Gallego, Mercedes

    2015-04-15

    Water used in a food factory is frequently disinfected with chlorine, which originates disinfection by-products: haloacetic acids (HAAs) make up the second most prevalent class of these products. In this paper we propose the first static HS-GC-MS method developed for direct HAA determination in beverages; the method has higher sensitivity, simplicity and reliability than the only alternative available in the literature. From 150 beverages analysed, it is possible to conclude that at least 2 HAAs (dichloro- and trichloroacetic acids, DCAA and TCAA) are always present in beverages prepared with treated water, which remains constant for 2 or 3 months in the beverages. Moreover, beverages of 100% fruit juices and soft drinks prepared with mineral water (free of HAAs) do not contain any HAA at significant values. Therefore, DCAA and TCAA may indicate of the presence of treated water in beverages.

  6. Ascorbic Acid Assisted Green Route for Synthesis of Water Dispersible Carbon Dots

    Institute of Scientific and Technical Information of China (English)

    NAWAZ Faisal; WANG Liang; ZHU Long-feng; MENG Xiang-ju; XIAO Feng-Shou

    2013-01-01

    Conventional quantum dots inherently carry the risk of cytotoxicity.Considering the biomedical limitations,an amino acid and vitamin were utilized to prepare highly luminescent carbon dots.Ascorbic acid and lysine were used to synthesize water soluble carbon dots which are highly biocompatible as both reactants and essential nutrients.

  7. Improved removal of ascorbate interference in the folin-ciocalteu assay of “total phenolic content”

    Science.gov (United States)

    The venerable Folin-Ciocalteu (F-C) assay for total phenolics can have severe limitations due to interference by ascorbic acid (AsA). For common fruit juices AsA interference can substantially exceed the magnitude of the total phenolic signal. Ascorbate oxidase (AO) has been a promising approach to ...

  8. Improved Folin-Ciocalteu assay of “total phenolic content” by removal of ascorbate and dehydroascorbate

    Science.gov (United States)

    The venerable and operationally simple Folin-Ciocalteu (F-C) assay for total phenolics can have severe limitations due to interference by ascorbic acid (AsA). For common fruit juices AsA interference can easily exceed the magnitude of the total phenolic signal itself. Ascorbate oxidase (AO) has been...

  9. Improved removal of ascorbate interference in the Folin-Ciocalteu assay of “total phenolic content"

    Science.gov (United States)

    The venerable Folin-Ciocalteu (F-C) assay for total phenolics can have severe limitations due to interference by ascorbic acid (AsA). For common fruit juices AsA interference can easily exceed the magnitude of the total phenolic signal itself. Ascorbate oxidase (AO) has been a promising approach to ...

  10. EFFECTS OF ASCORBIC ACID AND ACETYLSALICYLIC ACID SUPPLEMENTATION ON THE PERFORMANCE OF BROILER CHICKS EXPOSED TO HEAT STRESS

    Directory of Open Access Journals (Sweden)

    B. Anwar, S. A. Khan, A. Aslam, A. Maqbool1 and K. A. Khan

    2004-07-01

    Full Text Available A total of 100, day-old broiler chicks were randomly divided into 5 equal groups and kept under elevated temperature (93-97oF to see the effect of ascorbic acid and acetylsalicylic acid on the feed conversion ratio (FCR, immune status and ratio of weight of bursa, thymus and spleen to body weight. Heat stress increased the FCR but decreased the immune response and ratio of bursa, thymus and spleen to body weight of the birds. Ascorbic acid and acetylsalicylic acid supplementation during heat stress had beneficial effects on FCR, immune status and ratio of bursa, thymus and spleen to body weight. Grossly, bursa, thymus and spleen of heat stressed birds were atrophied but in ascorbic acid and acetylsalicylic acid supplemented birds these organs were not atrophied. No specific histopathological changes were observed in all groups.

  11. The Use of Ascorbate as an Oxidation Inhibitor in Prebiotic Amino Acid Synthesis: A Cautionary Note

    Science.gov (United States)

    Kuwahara, Hideharu; Eto, Midori; Kawamoto, Yukinori; Kurihara, Hironari; Kaneko, Takeo; Obayashi, Yumiko; Kobayashi, Kensei

    2012-12-01

    It is generally thought that the terrestrial atmosphere at the time of the origin of life was CO2-rich and that organic compounds such as amino acids would not have been efficiently formed abiotically under such conditions. It has been pointed out, however, that the previously reported low yields of amino acids may have been partially due to oxidation by nitrite/nitrate during acid hydrolysis. Specifically, the yield of amino acids was found to have increased significantly (by a factor of several hundred) after acid hydrolysis with ascorbic acid as an oxidation inhibitor. However, it has not been shown that CO2 was the carbon source for the formation of the amino acids detected after acid hydrolysis with ascorbic acid. We therefore reinvestigated the prebiotic synthesis of amino acids in a CO2-rich atmosphere using an isotope labeling experiment. Herein, we report that ascorbic acid does not behave as an appropriate oxidation inhibitor, because it contributes amino acid contaminants as a consequence of its reactions with the nitrogen containing species and formic acid produced during the spark discharge experiment. Thus, amino acids are not efficiently formed from a CO2-rich atmosphere under the conditions studied.

  12. The use of ascorbate as an oxidation inhibitor in prebiotic amino acid synthesis: a cautionary note.

    Science.gov (United States)

    Kuwahara, Hideharu; Eto, Midori; Kawamoto, Yukinori; Kurihara, Hironari; Kaneko, Takeo; Obayashi, Yumiko; Kobayashi, Kensei

    2012-12-01

    It is generally thought that the terrestrial atmosphere at the time of the origin of life was CO(2)-rich and that organic compounds such as amino acids would not have been efficiently formed abiotically under such conditions. It has been pointed out, however, that the previously reported low yields of amino acids may have been partially due to oxidation by nitrite/nitrate during acid hydrolysis. Specifically, the yield of amino acids was found to have increased significantly (by a factor of several hundred) after acid hydrolysis with ascorbic acid as an oxidation inhibitor. However, it has not been shown that CO(2) was the carbon source for the formation of the amino acids detected after acid hydrolysis with ascorbic acid. We therefore reinvestigated the prebiotic synthesis of amino acids in a CO(2)-rich atmosphere using an isotope labeling experiment. Herein, we report that ascorbic acid does not behave as an appropriate oxidation inhibitor, because it contributes amino acid contaminants as a consequence of its reactions with the nitrogen containing species and formic acid produced during the spark discharge experiment. Thus, amino acids are not efficiently formed from a CO(2)-rich atmosphere under the conditions studied.

  13. Enhancement of the Electrical Properties of CVD-Grown Graphene with Ascorbic Acid Treatment

    Science.gov (United States)

    Tang, Chunmiao; Chen, Zhiying; Zhang, Haoran; Zhang, Yaqian; Zhang, Yanhui; Sui, Yanping; Yu, Guanghui; Cao, Yijiang

    2016-02-01

    Ascorbic acid was used to modify to chemical vapor deposition (CVD)-grown graphene films transferred onto SiO2 substrate. Residual polymer (polymethyl methacrylate), Fe3+, Cl-, H2O, and O2 affected the electrical and thermal properties on graphene during the transfer or device fabrication processes. Exposure of transferred graphene to ascorbic acid resulted in significantly enhanced electrical properties with increased charge carrier mobility. All devices exhibited more than 30% improvement in room temperature carrier mobility in air. The carrier mobility of the treated graphene did not significantly decrease in 21 days. This result can be attributed to electron donation to graphene through the -OH functional group in ascorbic acid that is absorbed in graphene. This work provides a method to enhance the electrical properties of CVD-grown graphene.

  14. Equilibrium studies of cellulase aggregates in presence of ascorbic and boric acid.

    Science.gov (United States)

    Iram, Afshin; Amani, Samreen; Furkan, Mohammad; Naeem, Aabgeena

    2013-01-01

    The aggregate formation of cellulase was detected at 300 and 10 mM ascorbic and boric acid respectively. These aggregates showed reduced enzyme activity, loss in near-UV signal, decrease tryptophan and ANS fluorescence. They possess increase in non-native β-sheet structure as evident from far-UV CD and FTIR spectra, large hydrodynamic radii, increase thioflavin T fluorescence and shift in Congo red. Cellulase at 90 mM ascorbic acid exists as molten globule with retention of secondary structure, altered tryptophan environment, high ANS binding and loss in tertiary structure. Ascorbic acid acts as an antioxidant up to 90 mM and beyond this as a pro-oxidant.

  15. Dietary ascorbic acid and subsequent change in body weight and waist circumference

    DEFF Research Database (Denmark)

    Larsen, Sofus C; Angquist, Lars; Ahluwalia, Tarunveer Singh

    2014-01-01

    (∆BW) and waist circumference (∆WC). METHODS: A total of 7,569 participants' from MONICA, the Diet Cancer and Health study and the INTER99 study were included in the study. We combined 50 obesity associated single nucleotide polymorphisms (SNPs) in four genetic scores: a score of all SNPs and a score...... in anthropometry, and whether such associations may depend on genetic predisposition to obesity. Hence, we examined whether dietary ascorbic acid, possibly in interaction with the genetic predisposition to a high BMI, WC or waist-hip ratio adjusted for BMI (WHR), associates with subsequent annual changes in weight......BACKGROUND: Cross-sectional data suggests that a low level of plasma ascorbic acid positively associates with both Body Mass Index (BMI) and Waist Circumference (WC). This leads to questions about a possible relationship between dietary intake of ascorbic acid and subsequent changes...

  16. Crystal structures, circular dichroism spectra and absolute configurations of some ?-ascorbic acid derivatives

    Science.gov (United States)

    Wittine, Karlo; Gazivoda, Tatjana; Markuš, Marko; Mrvoš-Sermek, Draginja; Hergold-Brundić, Antonija; Cetina, Mario; Žiher, Dinko; Gabelica, Vesna; Mintas, Mladen; Raić-Malić, Silvana

    2004-01-01

    Chiral 2,3-O,O-dibenzyl ethers of L-ascorbic acid with 4-(5,6-epoxy)- (4) and 6-O-tosyl- (8) functional groups were studied by X-ray crystallography and circular dichroism (CD) spectroscopy. The stereostructure of 2,3-O,O-dibenzyl-5,6-isopropylidene-L-ascorbic acid (6) and 8 was determined by X-ray crystal structure analysis. Comparison of the CD-spectra of 4 and 8 with the CD-spectra of their synthetic precursors (2-3, 5-7) and L-ascorbic acid (1) itself, as well as crystal structures of 6 and 8 permitted to deduce the absolute configuration of 4. Thus, the chiral atoms C-4 and C-5 in 4 have R and S configurations, which is consistent with the configuration of 1.

  17. Synthesis of mesoporous silica materials with ascorbic acid as template via sol-gel process

    Institute of Scientific and Technical Information of China (English)

    PANG, Jie-Bina; QIU, Kun- Yuan; WEI, Yen

    2000-01-01

    Mesoporous silica materials with pore diameters of 2-5 nm have been prepared using ascorbic acid as a nonsurfactant tem plate or pore-forming agent in HCl-catalyzed sol-gel reactions of tetraethylorthosilicate, followed by removing the ascorbic acid compound by extrraction with ethanol. Characteriztion results from nitrogen sorption isotherm, powder X-ray diffraction and transmission electron microscopy indicate that the materials have large specific surface areas ( e. g. 1000 m2/g) and pore vohmes ( e. g. 0.8 cm3/g). The mesoporosity is arisen from interconnecting disordered wormlike channels and pores with relatively broad size distributions. As the ascorbic acid concen tration is increased, the pore diameters and pore volumes of the materials increase.

  18. Electrochemical impedance based chiral analysis of anti-ascorbutic drug: l-Ascorbic acid and d-ascorbic acid using C-dots decorated conductive polymer nano-composite electrode.

    Science.gov (United States)

    Pandey, Indu; Kant, Rama

    2016-03-15

    Clinical manifestations owing to l-ascorbic acid for scurvy as comparison to d-ascorbic acid and challenges of chiral purity are overcome by using chiral selective conductive polymer nanocomposite which mimics antibodies and enzymes. A novel chiral selective imprinted polyaniline-ferrocene-sulfonic acid film has been electrochemically fabricated on C-dots modified pencil graphite electrode. The performance of the obtained l-ascorbic acid or d-ascorbic acid chiral selective sensor was investigated by electrochemical impedance spectroscopy, cyclic and differential pulse voltammetry. The surface characteristics of the C-dots, chiral sensor before and after the de-doping of chiral d- and l-ascorbic acid were characterized by scanning electron microscopy, Raman spectroscopy and X-ray diffraction spectroscopy. Excellent recognition results were obtained by difference in electron transfer resistance. The proposed chiral sensor is capable of measuring d-ascorbic acid or l-ascorbic acid in aqueous as well as in real and commercial samples within the range of 0.020-0.187 nM and 0.003-0.232 nM with detection limit of 0.00073 nM and 0.00016 nM, respectively. The proposed method has also been examined for the chiral selective recognition of ascorbic acid isomers (d- and l-) quantitatively, in complicated matrices of real samples.

  19. Effect of Ascorbic Acid on Noise Induced Hearing Loss in Rats

    Directory of Open Access Journals (Sweden)

    Ziba Loukzadeh

    2015-07-01

    Full Text Available Introduction: After presbycusis, noise-induced hearing loss is the second most common cause of acquired hearing loss. Numerous studies have shown that high-intensity noise exposure increases free radical species; therefore, use of antioxidants to detoxify the free radicals can prevent cellular damage in the cochlea. We studied the potential hearing protective effect of different doses of ascorbic acid administered prior to noise exposure in rats.   Materials and Methods: Twenty-four male albino Wistar rats were randomly allocated into four groups: groups A, B, and C received 1250, 250, and 50 mg/kg/day of ascorbic acid, respectively, and group D acted as the control group. After 14 days of ascorbic acid administration, the rats were exposed to noise (105 dB sound pressure level for 2 h. Distortion product otoacoustic emissions (DPOAE were recorded prior to starting the ascorbic acid as baseline and 1 h after the noise exposure.   Results: The amplitude decrease was 14.99 dB for group A, 16.11 dB for group B, 28.82 dB for group C, and 29.91 dB for the control group. Moderate and high doses of ascorbic acid significantly reduced the transient threshold shift in the rats.   Conclusion:  The results of present study support the concept of cochlea protection by antioxidant agents. This dose-dependent protective effect was shown through the use of ascorbic acid treatment prior to noise exposure.

  20. Ascorbic acid enables reversible dopamine receptor /sup 3/H-agonist binding

    Energy Technology Data Exchange (ETDEWEB)

    Leff, S.; Sibley, D.R.; Hamblin, M.; Creese, I.

    1981-11-16

    The effects of ascorbic acid on dopaminergic /sup 3/H-agonist receptor binding were studied in membrane homogenates of bovine anterior pituitary and caudate, and rat striatum. In all tissues virtually no stereospecific binding (defined using 1uM (+)butaclamol) of the /sup 3/H-agonists N-propylnorapomorphine (NPA), apomorphine, or dopamine could be demonstrated in the absence of ascorbic acid. Although levels of total /sup 3/H-agonist binding were three to five times greater in the absence than in the presence of 0.1% ascorbic acid, the increased binding was entirely non-stereospecific. Greater amounts of dopamine-inhibitable /sup 3/H-NPA binding could be demonstrated in the absence of 0.1% ascorbic acid, but this measure of ''specific binding'' was demonstrated not to represent dopamine receptor binding since several other catecholamines and catechol were equipotent with dopamine and more potent than the dopamine agonist (+/-)amino-6,7-dihydroxy-1,2,3,4-tetrahydronapthalene (ADTN) in inhibiting this binding. High levels of dopamine-displaceable /sup 3/H-agonist binding were detected in fresh and boiled homogenates of cerebellum, an area of brain which receives no dopaminergic innervation, further demonstrating the non-specific nature of /sup 3/H-agonist binding in the absence of ascorbic acid. These studies emphasize that under typical assay conditions ascorbic acid is required in order to demonstrate reversible and specific /sup 3/H-agonist binding to dopamine receptors.

  1. Effects of Ascorbic Acid and FSH on the Maturation of Mice's Oocytes and Follicles

    Directory of Open Access Journals (Sweden)

    Barzegari Firouzabadi

    2011-11-01

    Full Text Available Introduction: Progress in laboratory culture conditions for in vitro oocyte maturation has led to development of the treatment of human and animal infertility. In this study we investigated the effects of FSH and ascorbic acid on the in vitro maturation of mouse's follicles and enclosed oocytes. Methods: For experiment, intact pre-antral follicles were isolated from the ovaries of 6 week-old female mice and cultured in TCM-199 medium. Special quantities of FSH and ascorbic acid were added to the culture medium (containing 25-30 follicles during separate experiments: 5, 20, 40, 60, 100, 140, 180 and 220 IU/L of FSH and 20, 40, 80, 240, 300 and 400 nmol/mL of ascorbic acid. Follicles were cultured for 6 days in an incubator at 37 °C, 92% humidity and 5% air CO2. Our study was semi-experimental. The entire statistical analysis was carried out by SPSS (version 14.0 for Windows using one way ANOVA. Post Hoc tests were used for the multiple comparisons at 95% confidence interval. P values < 0.05 were considered statistically significant. Results: At FSH concentration of 100 IU/L increase in follicle diameter (190µm, survival rate (91%, germinal vesicle breakdown (GVBD (81% and oocyte maturation rates (61% was observed (p ≥0.05. Ascorbic acid increased survival rate (42%, p<0.001 but didn’t affect diameter, GVBD and oocyte maturation rates. Conclusion: Ascorbic acid and FSH-containing medium showed a marked increase in all parameters except for follicle diameter. FSH and ascorbic acid increase the maturation rate of follicles and enclosed oocytes but if they are supplied in a combination, this growth rate can be significantly increased

  2. Quality assessment of fruit juices by NIR spectroscopy

    Directory of Open Access Journals (Sweden)

    Petr Šnurkovič

    2013-01-01

    Full Text Available In the article there is described the detection of substances used for adulteration of fruit juices. They were investigated in juice products distributed within the network of retail markets. This detection was performed using the method of near-infrared spectroscopy (NIR. There were analysed samples of orange juices, apple juices, and grapefruit juices. At the beginning, there were assessed quality parameters (soluble dry matter, total acids, formol number, malic acid, citric acid, ascorbic acid, lactic acid, specific density, and ethanol content and their compatibility with the limit values specified by the Association of the Industries of Juices and Nectars. The research covered 45 kinds of fruit juices and there was found 10 cases when at least one parameter was out of the approved limits. After that there was used the discrimination analysis and it enabled to separate pure juices from those containing at least 1 % of admixtures. This method also helped to distinguish between the group of fresh squeezed juices and the juices made of fruit concentrates. Using the diagnostics “Principal Component Scores 3D Display”, there were arranged various numbers of similar groups of juice samples with similar compound profiles.

  3. Organic Acids, Sugars, and Anthocyanins Contents in Juices of Tunisian Pomegranate Fruits

    OpenAIRE

    Hasnaoui, Nejib; Jbir, Rania; Mars, Messaoud; TRIFI, Mokhtar; Kamal-Eldin, Afaf; Melgarejo, Pablo; Hernandez, Francisca

    2011-01-01

    Juices made from fruits of 30 Tunisian accessions of pomegranate were studied for their organic acids, sugars, and anthocyanin contents, using high performance liquid chromatography. Among the detected organic acids, malic acid was the major one (>50%) followed by citric acid (>22%), while among sugars, fructose and glucose were most present in pomegranate juice contributing 53.9 and 43.4% of the total sugar content, respectively. The total anthocyanin content ranged from 9-115 mg per litre o...

  4. Changes in nutritional and sensory properties of orange juice packed in PET bottles: an experimental and modelling approach.

    Science.gov (United States)

    Bacigalupi, Celine; Lemaistre, Marie Hélène; Boutroy, Naima; Bunel, Christophe; Peyron, Stéphane; Guillard, Valérie; Chalier, Pascale

    2013-12-15

    Sensitivity to oxidation of an orange juice was investigated through packaging in standard PET or active PET with oxygen scavenger bottles. The evolution of dissolved oxygen was found to be similar in all bottles, whereas ascorbic acid degradation was related to the oxygen transfer with higher losses in standard PET (53%) against active PET (31%). Moreover, when juice was exposed to high intensity light, a fold faster degradation of ascorbic acid was observed compared to total darkness. Depending also on the light intensity and regardless of the package permeability, changes in the aromatic profile of the juice were observed due to the degradation of limonene and the formation of α-terpineol, an off-flavour. A mechanistic model was developed to predict the shelf life of orange juice. This model, coupling O2 transfer and ascorbic acid oxidation reaction in the bottled juice, confirmed that oxygen permeation through packaging material could not be neglected.

  5. Contributions of phenolics and added vitamin C to the antioxidant capacity of pomegranate and grape juices: synergism and antagonism among constituents.

    Science.gov (United States)

    Bolling, Bradley W; Chen, Ya-Yen; Chen, C-Y Oliver

    2013-12-01

    The aim of this study was to examine the contribution of sugar, organic acid, neutral phenol, and anthocyanin fractions and added ascorbic acid to grape and pomegranate-nectarine juice total phenol, ORAC, FRAP, and DPPH values. Neutral phenol and anthocyanin fractions contributed ≥75% of the total antioxidant capacity (TAC) for both juices. Intrinsic synergy and antagonism among the fractionated constituents occurred inconsistently in each assay. Sugars and organic acids antagonized pomegranate juice neutral phenols and anthocyanins in the DPPH assay by 50% and the grape juice ORAC value by 21%, but were synergistic to the grape juice FRAP value. The added ascorbic acid was dose-dependently synergistic with pomegranate and grape juice total phenol, DPPH, and FRAP assays, but less so in the ORAC assay. Thus, the interactions between grape and pomegranate juice constituents determine TAC and total phenol values, and synergy in these assays could not be attributed solely to polyphenols.

  6. Study on NO2 absorption by ascorbic acid and various chemicals

    Institute of Scientific and Technical Information of China (English)

    LI Wei; WU Cheng-zhi; FANG He-liang; SHI Yao; LEI Le-cheng

    2006-01-01

    Study on NO2 absorption aimed at seeking a better NO2 absorption chemical at pH 4.5~7.0 for application to existing wet flue gas desulfurization (FGD). The results from the double-stirred reactor indicated thru ascorbic acid has very high absorption rate at this pH range. The rate constant of ascorbic acid reaction with NO2 (0~1000× 10-6 mol/mol) is about 3.54× 106 mol/(L.s)at pH 5.4~6.5 at 55 ℃.

  7. Ascorbic acid inhibits replication and infectivity of avian RNA tumor virus

    Energy Technology Data Exchange (ETDEWEB)

    BISSELL, MINA J; HATIE, CARROLL; FARSON, DEBORAH A.; SCHWARZ, RICHARD I.; SOO, WHAI-JEN

    1980-04-01

    Ascorbic acid, at nontoxic concentrations, causes a substantial reduction in the ability of avian tumor viruses to replicate in both primary avian tendon cells and chicken embryo fibroblasts. The virus-infected cultures appear to be less transformed in the presence of ascorbic acid by the criteria of morphology, reduced glucose uptake, and increased collagen synthesis. The vitamin does not act by altering the susceptibility of the cells to initial infection and transformation, but instead appears to interfere with the spread of infection through a reduction in virus replication and virus infectivity. The effect is reversible and requires the continuous presence of the vitamin in the culture medium.

  8. Ascorbic acid inhibits TPA-induced HL-60 cell differentiation by decreasing cellular H₂O₂ and ERK phosphorylation.

    Science.gov (United States)

    Yiang, Giou-Teng; Chen, Jen-Ni; Wu, Tsai-Kun; Wang, Hsueh-Fang; Hung, Yu-Ting; Chang, Wei-Jung; Chen, Chinshuh; Wei, Chyou-Wei; Yu, Yung-Luen

    2015-10-01

    Retinoic acid (RA), vitamin D and 12-O‑tetradecanoyl phorbol-13-acetate (TPA) can induce HL-60 cells to differentiate into granulocytes, monocytes and macrophages, respectively. Similar to RA and vitamin D, ascorbic acid also belongs to the vitamin family. High‑dose ascorbic acid (>100 µM) induces HL‑60 cell apoptosis and induces a small fraction of HL‑60 cells to express the granulocyte marker, CD66b. In addition, ascorbic acid exerts an anti‑oxidative stress function. Oxidative stress is required for HL‑60 cell differentiation following treatment with TPA, however, the effect of ascorbic acid on HL‑60 cell differentiation in combination with TPA treatment remains to be fully elucidated. The aim of the present study was to investigate the cellular effects of ascorbic acid treatment on TPA-differentiated HL-60 cells. TPA-differentiated HL-60 cells were used for this investigation, this study and the levels of cellular hydrogen peroxide (H2O2), caspase activity and ERK phosphorylation were determined following combined treatment with TPA and ascorbic acid. The results demonstrated that low‑dose ascorbic acid (5 µM) reduced the cellular levels of H2O2 and inhibited the differentiation of HL‑60 cells into macrophages following treatment with TPA. In addition, the results of the present study further demonstrated that low‑dose ascorbic acid inactivates the ERK phosphorylation pathway, which inhibited HL‑60 cell differentiation following treatment with TPA.

  9. Determination of ascorbic acid and carotenoids in food commodities by liquid chromatography with mass spectrometry detection.

    Science.gov (United States)

    Frenich, A Garrido; Torres, M E Hernández; Vega, A Belmonte; Vidal, J L Martínez; Bolaños, P Plaza

    2005-09-21

    Two methods, one to determine ascorbic acid and one to determine lycopene and beta-carotene, in vegetables and fruits by liquid chromatography coupled with mass spectrometry (LC-MS) have been established. The chromatographic separation of the studied compounds and their MS parameters were optimized to improve selectivity and sensitivity. In both methods, separation was carried out with two coupled columns, first a C(18) and then a dC(18), using as mobile phase 70% methanol (0.005% acetic acid) and 30% acetic acid 0.05% for ascorbic acid determination and a mixture of methanol, tetrahydrofuran, and acetonitrile (60:30:10 v/v/v) for carotenoid analysis in isocratic mode. The molecular ion was selected for the quantification in selective ion monitoring (SIM) mode. Ascorbic acid was detected with electrospray ionization probe (ESI) in negative mode, while chemical ionization atmospheric pressure (APCI) in positive mode was used for the target carotenoids. The methodology for ascorbic acid analysis is based on an extraction with polytron using methanol and a mixture of methaphosphoric acid and acetic acid. Extraction of the carotenoids was carried out with tetrahydrofuran/methanol (1:1) (v/v). The proposed methods were applied, after their corresponding validations, to the analysis of four varieties of tomatoes, tomato in tin enriched and dried tomato, and to the analysis of mango and kiwi fruits, to compare the content in these compounds. Moreover, the influence of the process of freezing and the effect that the manipulation/preservation has in the content of ascorbic acid in tomato have also been studied.

  10. Amino Acid Profile as a Feasible Tool for Determination of the Authenticity of Fruit Juices

    Directory of Open Access Journals (Sweden)

    Mostafa Asadpoor

    2014-12-01

    Full Text Available Purpose: Fruit juice is a nutrient rich food product with a direct connection to public health. The purpose of this research was to determine the amino acid profile of juices and provide a quick and accurate indicator for determining their authenticity. Methods: The method of analysis was HPLC with fluorescence detector and pre-column derivatization by orthophtaldialdehyde (OPA. Sixty-six samples of fruit juices were analyzed, and fourteen amino acids were identified and determined in the sampled fruit juices. The fruit samples used for this analysis were apples, oranges, cherry, pineapple, mango, apricot, pomegranate, peach and grapes. Results: The results showed that 32% of samples tested in this study had a lower concentrate percentage as compared to that of their labels and/or other possible authenticity problems in the manufacturing process. The following samples showed probable adulteration: four cherry juice samples, two pomegranate juice samples, one mango, three grape, four peach, seven orange, two apple and one apricot juice samples. Conclusion: In general, determining the amount of amino acids and comparing sample amino acids profiles standard values seems to be an indicator for quality control. This method can the regulatory agencies with a tool, to help produce a healthier The aim of this study is the analytical control of the fruit juice composition is becoming an important issue, and HPLC can provide an important and essential tool for more accurate research as well as for routine analysis.

  11. UlaR activates expression of the ula operon in Streptococcus pneumoniae in the presence of ascorbic acid

    NARCIS (Netherlands)

    Afzal, Muhammad; Shafeeq, Sulman; Henriques-Normark, Birgitta; Kuipers, Oscar P

    2015-01-01

    In this study, the regulatory mechanism of the ula (utilization of l-ascorbic acid) operon, putatively responsible for transport and utilization of ascorbic acid in Streptococcus pneumoniae strain D39, is studied. β-Galactosidase assay data demonstrate that expression of the ula operon is increased

  12. Effect of salinity and ascorbic acid on growth, water and osmotic relations of Lepidium sativum

    Directory of Open Access Journals (Sweden)

    Azadeh Najjar-Khodabakhsh

    2015-06-01

    Full Text Available Soil salinity is a serious environmental problem in arid and semi-arid regions that have negative impacts on crop production. In this research, because of medicinal and nutritional importance of the garden cress (Lepidium sativum plant, the interactive effects of salinity (225 mM NaCl and ascorbic acid (1 mM were evaluated on growth and its water relations. A completely randomized design with four replications was conducted under controlled conditions. The results showed that salinity decreased growth, relative water content, osmotic potential and soluble proteins and increased soluble sugars, amino acids and proline contents. Many of salinity damaged characteristic were improved by adding exogenous ascorbic acid to salty environment. Exogenous ascorbic acid alone, in comparison with control, enhanced the growth of garden cress by increasing relative water content, soluble sugars and soluble proteins contents. The results indicated that usage of ascorbic acid, as an antioxidant, reduced harmful effects of salinity stress and led to growth improvement in garden cress plants.

  13. Synergistic protective effects of ceftriaxone and ascorbic acid against subacute deltamethrin-induced nephrotoxicity in rats.

    Science.gov (United States)

    Abdel-Daim, Mohamed M; El-Ghoneimy, Ashraf

    2015-03-01

    Deltamethrin (DLM) is a synthetic class II pyrethroid acaricide and insecticide widely used for veterinary and agricultural purposes. However, its animal and human exposure leads to nephrotoxicity. Our experimental objective was to evaluate protective effects of ceftriaxone and/or ascorbic acid against DLM-induced renal injury in male Wistar albino rats. DLM-treated animals revealed significant alterations in serum biochemical parameters related to renal injury; urea, uric acid and creatinine. There was a significant increase in renal lipid peroxidation and a significant inhibition in antioxidant biomarkers. Moreover, DLM significantly reduced serum acetylcholinesterase (AChE) activity. In addition, It induced serum and kidney tumor necrosis factor-α (TNF-α). Both ceftriaxone and ascorbic acid protect against DLM-induced biochemical alterations in serum and renal tissue when used alone or in combination along with DLM-intoxication. Furthermore, both ceftriaxone and ascorbic acid produced synergetic nephroprotective and antioxidant effects. Therefore, it could be concluded that ceftriaxone and/or ascorbic acid administration able to minimize the toxic effects of DLM through their free radical-scavenging and potent antioxidant activity.

  14. Carotene reactivity in pink grapefruit juice elucidated from model systems and multiresponse modeling.

    Science.gov (United States)

    Achir, Nawel; Hadjal, Thiziri; Madani, Khodir; Dornier, Manuel; Dhuique-Mayer, Claudie

    2015-04-22

    This study was carried out to assess the impact of pink grapefruit juice composition and structure on the degradation kinetics of lycopene and β-carotene using model systems and multiresponse modeling. Carotenes were heated at four temperatures in their native matrix (juice) or were extracted and incorporated in water/ethanol emulsion systems formulated with or without ascorbic acid or naringin. Kinetic analysis showed that the rate constants and activation energy were lower for lycopene than for β-carotene in the juice, while this trend was inversed in the model system. Multiresponse modeling was used to analyze the role of ascorbic acid and naringin in carotene degradation. Ascorbic acid had a very low impact, while naringin significantly increased the carotene degradation and isomerization rates. We concluded that lycopene was more sensitive to thermal degradation and phytochemical interactions than β-carotene, but this behavior was masked in the fruit juice matrix by better structural protection.

  15. Similarity of the yellow chromophores isolated from human cataracts with those from ascorbic acid-modified calf lens proteins: evidence for ascorbic acid glycation during cataract formation.

    Science.gov (United States)

    Cheng, R; Lin, B; Lee, K W; Ortwerth, B J

    2001-07-27

    Chromatographic evidence supporting the similarity of the yellow chromophores isolated from aged human and brunescent cataract lenses and calf lens proteins ascorbylated in vitro is presented. The water-insoluble fraction from early stage brunescent cataract lenses was solubilized by sonication (WISS) and digested with a battery of proteolytic enzymes under argon to prevent oxidation. Also, calf lens proteins were incubated with ascorbic acid for 4 weeks in air and submitted to the same digestion. The percent hydrolysis of the proteins to amino acids was approximately 90% in every case. The content of yellow chromophores was 90, 130 and 250 A(330) units/g protein for normal human WISS, cataract WISS and ascorbate-modified bovine lens proteins respectively. Aliquots equivalent to 2.0 g of digested protein were subjected to size-exclusion chromatography on a Bio-Gel P-2 column. Six peaks were obtained for both preparations and pooled. Side by side thin-layer chromatography (TLC) of each peak showed very similar R(f) values for the long wavelength-absorbing fluorophores. Glycation with [U-(14)C]ascorbic acid, followed by digestion and Bio-Gel P-2 chromatography, showed that the incorporated radioactivity co-eluted with the A(330)-absorbing peaks, and that most of the fluorescent bands were labeled after TLC. Peaks 2 and 3 from the P-2 were further fractionated by preparative Prodigy C-18 reversed-phase high-performance liquid chromatography. Two major A(330)-absorbing peaks were seen in peak 2 isolated from human cataract lenses and 5 peaks in fraction 3, all of which eluted at the same retention times as those from ascorbic acid glycated calf lens proteins. HPLC fractionation of P-2 peaks 4, 5 and 6 showed many A(330)-absorbing peaks from the cataract WISS, only some of which were identical to the asorbylated proteins. The major fluorophores, however, were present in both preparations. These data provide new evidence to support the hypothesis that the yellow

  16. Factors that affect leaf extracellular ascorbic acid content and redox status

    Energy Technology Data Exchange (ETDEWEB)

    Burkey, K.O.; Fiscus, E.L. [North Carolina State Univ., United States dept. og Agriculture-Agricultural Research Service and Dept. of Crop Science, Raleigh, NC (United States); Eason, G. [North Carolina, State Univ., United States Dept. of Plant Pathology, Raleigh, NC (United States)

    2003-01-01

    Leaf ascorbic acid content and redox status were compared in ozone-tolerant (Provider) and ozone-sensitive (S156) genotypes of snap bean (Phaseolus vulgaris L.). Plants were grown in pots for 24 days under charcoal-filtered air (CF) conditions in open-top field chambers and then maintained as CF controls (29 nmol mol{sup 1} ozone) or exposed to elevated ozone (71 nmol mol{sup 1} ozone). Following a 10-day treatment, mature leaves of the same age were harvested early in the morning (06:00-08:00 h) or in the afternoon (13:00-15:00 h) for analysis of ascorbic acid (AA) and dehydroascorbic acid (DHA). Vacuum infiltration methods were used to separate leaf AA into apoplast and symplast fractions. The total ascorbate content [AA + DHA] of leaf tissue averaged 28% higher in Provider relative to S156, and Provider exhibited a greater capacity to maintain [AA + DHA] content under ozone stress. Apoplast [AA + DHA] content was 2-fold higher in tolerant Provider (360 nmol g{sup 1} FW maximum) relative to sensitive S156 (160 nmol g1 FW maximum) regardless of sampling period or treatment, supporting the hypothesis that extracellular AA is a factor in ozone tolerance. Apoplast [AA + DHA] levels were significantly higher in the afternoon than early morning for both genotypes, evidence for short-term regulation of extracellular ascorbate content. Total leaf ascorbate was primarily reduced with AA/[AA + DHA] ratios of 0.81-0.90. In contrast, apoplast AA/[AA + DHA] ratios were 0.01-0.60 and depended on genotype and ozone treatment. Provider exhibited a greater capacity to maintain extracellular AA/[AA + DHA] ratios under ozone stress, suggesting that ozone tolerance is associated with apoplast ascorbate redox status. (au)

  17. Profiling the Changes in Signaling Pathways in Ascorbic Acid/beta-Glycerophosphate-Induced Osteoblastic Differentiation

    NARCIS (Netherlands)

    Chaves Neto, Antonio Hernandes; Queiroz, Karla Cristiana; Milani, Renato; Paredes-Gamero, Edgar Julian; Justo, Giselle Zenker; Peppelenbosch, Maikel P.; Ferreira, Carmen Verissima

    2011-01-01

    Despite numerous reports on the ability of ascorbic acid and beta-glycerophosphate (AA/beta-GP) to induce osteoblast differentiation, little is known about the molecular mechanisms involved in this phenomenon. In this work, we used a peptide array containing specific consensus sequences (potential s

  18. Stability in fish feed and bioavailability to rainbow trout of two ascorbic acid forms

    DEFF Research Database (Denmark)

    Skelbaek, T.; Andersen, Niels Gerner; Winning, M.

    1990-01-01

    The stability in warm pelleted fish feed and the bioavailability to rainbow trout of crystalline ascorbic acid (AA) and a synthetic polymer-coated AA product (PCAA) were compared. The AA loss during pelleting was 29% for crystalline AA and 19% for PCAA. After 6 weeks at room temperature 73% of PCAA...

  19. Analysis of Ascorbic Acid in Single Human Neutrophils by Electrochemical Detection

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Ascorbic acid in individual human neutrophils was determined by capillary zone electrophoresis with electrochemical detection. In order to overcome the influence of the adsorption of the substances in cells on the inner surface wall of the capillary on the migration time and the number of theoretical plates, a procedure for treating capillaries has been described.

  20. Elimination of ascorbic acid after high-dose infusion in prostate cancer patients

    DEFF Research Database (Denmark)

    Nielsen, Torben Kjær; Højgaard, Martin; Andersen, Jon Thor Trærup

    2015-01-01

    Treatment with high-dose intravenous (IV) ascorbic acid (AA) is used in complementary and alternative medicine for various conditions including cancer. Cytotoxicity to cancer cell lines has been observed with millimolar concentrations of AA. Little is known about the pharmacokinetics of high dose...

  1. Ascorbic acid prevents cimetidine-induced decrease of serum hydrocortisone concentrations

    NARCIS (Netherlands)

    M.P. Boidin (Marinus Pieter); A. Stuurman (Arie); W. Erdmann (Wilhelm)

    1990-01-01

    markdownabstractAbstract A blind, parallel, prospective, clinical study was conducted to investigate the effect of ascorbic acid on human serum hydrocortisone concentrations which were decreased by the administration of cimetidine. The study population included 16 male adults scheduled for major a

  2. Impact of Ascorbic Acid Fortification on the Effectiveness of Biological Control Agents

    Science.gov (United States)

    Recent developments in genetic engineering have paved the way for researchers to produce crops of high nutritional and yield value, in addition to being resistant to diseases and pests. Ascorbic acid content is one of the nutritive parameters researchers are trying to enhance in plants. This study ...

  3. Ascorbic Acid Profiles in 'Delicious' and 'Honeycrisp' Apples During on-Tree Development and Cold Storage

    Science.gov (United States)

    Reactive oxygen species (ROS) produced in plants are involved in a number of processes both beneficial (signal transduction) and detrimental (induction of physiological disorders). ROS toxicity can be ameliorated by a number of metabolic systems or compounds in plant tissue including L-Ascorbic acid...

  4. Developmental response of the beneficial predator Podisus maculiventris to change in dietary ascorbic acid concentration

    Science.gov (United States)

    We report here the effects of ascorbic acid concentrations (0.07, 0.3, 3.0 and 30.0 g/L) in artificial diets on growth rates, adult weights, fecundity and survival of the predatory stink bug, Podisus maculiventris. Overall, a dietary level of 3.0 g/L gave the shortest developmental times over both ...

  5. Plasma ascorbic acid, a priori diet quality score, and incident hypertension

    NARCIS (Netherlands)

    Buijsse, Brian; Jacobs, D.R.; Steffen, L.M.; Kromhout, Daan; Gross, M.D.

    2015-01-01

    Vitamin C may reduce risk of hypertension, either in itself or by marking a healthy diet pattern. We assessed whether plasma ascorbic acid and the a priori diet quality score relate to incident hypertension and whether they explain each other's predictive abilities. Data were from 2884 black and

  6. Ascorbic acid, cognitive function, and Alzheimer’s disease: a current review and future direction

    OpenAIRE

    Bowman, Gene L.

    2012-01-01

    This narrative review appraises the human and animal studies implicating ascorbic acid (AA) in normal cognitive function and Alzheimer’s disease. A research framework for how nutrition affects brain aging is proposed with emphasis on AA intake, status, metabolism, and transport into brain tissue. A final synopsis highlights areas for future research regarding AA nourishment and healthy brain aging.

  7. CAPSAICIN AND ASCORBIC ACID VARIABILITY IN CHILLI AND PAPRIKA CULTIVARS AS REVEALED BY HPLC ANALYSIS

    Directory of Open Access Journals (Sweden)

    Samuel Tilahun

    2013-10-01

    Full Text Available Capsaicin and ascorbic acid contents of seven Indian peppers varieties/accessions from Capsicum annuum (CA 97, CCH, K1, KTPL19, Arka Abhir and Bayadagi Kaddi and C. frutescens (CF1 species were determined using High Performance Liquid Chromatography (HPLC. Based on their pungency value, all the chilli accession/varieties (CA 97, CCH, K1, and CF 1 were classified as highly pungent peppers. The accession CF1 showed the highest concentration of capsaicin (445mg 100g -1 DW with corresponding pungency value of 71,200 SHUs and Arka Abhir variety showed the lowest capsaicin concentration (29mg 100g -1 DW with 4,672 SHUs of pungency value. Similarly, Bayadaggi kaddi variety showed the highest ascorbic acid content (189 mg/100 FW and the accession CA 97 showed the lowest ascorbic acid contents (55.3 mg/100 FW. The variability in capsaicin and ascorbic acid content presented in the pepper germplasm can be exploited for breeding cultivars with improved nutritional qualities. Moreover, CF1and Bayadagi kaddi can be used as a potential source for capsaicin and vitamin C, respectively.

  8. CAPSAICIN AND ASCORBIC ACID VARIABILITY IN CHILLI AND PAPRIKA CULTIVARS AS REVEALED BY HPLC ANALYSIS

    Directory of Open Access Journals (Sweden)

    Samuel Tilahun

    2013-08-01

    Full Text Available Capsaicin and ascorbic acid contents of seven Indian peppers varieties/accessions from Capsicum annuum (CA 97, CCH, K1, KTPL19, Arka Abhir and Bayadagi Kaddi and C. frutescens (CF1 species were determined using High Performance Liquid Chromatography (HPLC. Based on their pungency value, all the chilli accession/varieties (CA 97, CCH, K1, and CF 1 were classified as highly pungent peppers. The accession CF1 showed the highest concentration of capsaicin (445mg 100g -1 DW with corresponding pungency value of 71,200 SHUs and Arka Abhir variety showed the lowest capsaicin concentration (29mg 100g -1 DW with 4,672 SHUs of pungency value. Similarly, Bayadaggi kaddi variety showed the highest ascorbic acid content (189 mg/100 FW and the accession CA 97 showed the lowest ascorbic acid contents (55.3 mg/100 FW. The variability in capsaicin and ascorbic acid content presented in the pepper germplasm can be exploited for breeding cultivars with improved nutritional qualities. Moreover, CF1and Bayadagi kaddi can be used as a potential source for capsaicin and vitamin C, respectively.

  9. Design, synthesis and preliminary biological evaluation of brain targeting L-ascorbic acid prodrugs of ibuprofen

    Institute of Scientific and Technical Information of China (English)

    Xue-Ying Wu; Xiao-Cen Li; Jie Mi; Jing You; Li Hai

    2013-01-01

    L-Ascorbic acid (AA,vitamin C) exhibits a high concentration in the brain.The transportation of AA in brain is mainly mediated by the glucose transporter 1 (GLUT1) and the Na+-dependent vitamin C transporter SVCT2.While L-ascorbic acid C6-O conjugation has been investigated as a tool to enhance brain drug delivery,C5-O conjugation and C5-O & C6-O conjugation as brain targeting tools have not been reported.In this letter,ibuprofen was linked directly to C5-O,C6-O and C5-O & C6-O positions of L-ascorbic acid with eater bonds,providing prodrug 1,2 and 3,respectively,to improve their targeting abilities in the brain.Prodrug 1,2 and 3 were synthesized in facile ways with good yields.And the preliminary evaluation in vivo illustrated that prodrug 2 had a better targeting ability than prodrug 1.Moreover,prodrug 3,whose C5-O & C6-O positions were both modified,had good targeting ability for brain which will provide an important evidence for our further study on C5-O-& C6-O-di-derivatives of L-ascorbic acid.

  10. Exogenous application of ascorbic acid stimulates growth and photosynthesis of wheat (Triticum aestivum L. under drought

    Directory of Open Access Journals (Sweden)

    Samina Malik and Muhammad Ashraf

    2012-05-01

    Full Text Available Drought causes considerable reduction in plant growth. A hydroponic experiment was conducted to appraise the potential role of exogenously applied ascorbic acid in alleviating the effect of drought on wheat. Two contrasting wheat genotypes, a drought tolerant cultivar Chakwal-86 and a drought sensitive strain 6544-6 were used in the study. Drought was induced by dissolving 20% Polyethylene glycol (PEG8000 in the nutrient solution producing -0.6MPa osmotic stress. Drought caused a significant decrease in chlorophyll pigments and net photosynthesis resulting in growth reduction of both wheat genotypes. However, this decrease was more severe in the genotype 6544-6 compared to Chakwal-86. Ascorbic acid (AsA was applied through rooting medium, as a foliar spray and seed soaking treatment. Ascorbic acid treated seedlings of both genotypes maintained higher chlorophyll contents, net photosynthesis and growth compared to the non-treated plants. Of the three different modes of ascorbic acid application, rooting medium was more effective in alleviating the adversities of drought in wheat. `

  11. Effects of Ascorbic Acid and Reduced Glutathione on the Alleviation of Salinity Stress in Olive Plants

    NARCIS (Netherlands)

    Aliniaeifard, S.; Hajilou, J.; Tabatabaei, S.J.; Seifi Kalhor, Maryam

    2016-01-01

    The aim of this study was to evaluate the effects of low molecular mass antioxidants and NaCl salinity on growth, ionic balance, proline, and water contents of ‘Zard’ olive trees under controlled greenhouse conditions. The experiment was carried out by spraying 2 mM of ascorbic acid (Asc) and 3 m

  12. Evaluation of total carotenoids and ascorbic acid in osmotic pretreated guavas during convective drying

    NARCIS (Netherlands)

    Sanjinez-Argandona, EJ; Cunha, RL; Menegalli, FC; Hubinger, MD

    2005-01-01

    Degradation of ascorbic acid and carotenoid content in osmotic pretreated and convective dried guavas was investigated. The osmotic dehydration was performed in a semi-continuous flow osmotic contactor at 40 degrees C for two hours with sucrose solution at 60% (w/ w). Pretreated guava sticks were dr

  13. Effect of preservation method and storage condition on ascorbic acid loss in beverages

    Directory of Open Access Journals (Sweden)

    Jokanović Marija R.

    2009-01-01

    Full Text Available Global market is flooded with vitamin-enriched foods, mainly beverages. Major vitamins for enriching beverages are the antioxidant vitamins A, C and E. Ascorbic acid is readily oxidized and lost during storage of the beverages, at rates depending on the conditions of storage. This fact is of great importance for the consumer who must know how to store beverages and when to consume them in order to get the maximum benefit of added vitamin C. The objective of this paper was to determine the amount of ascorbic acid lost in beverages applying different preservation methods and storage condition. Beverage was made in laboratory conditions with synthetic L-ascorbic acid added according to the national legislations. After 30 days of storage at 4-8oC ascorbic acid overall loss was from 81.01% to 90.27% in thermally pasteurized samples and from 97.83 % to almost complete loss in samples preserved with sodium benzoate.

  14. A method for the determination of ascorbic acid using the iron(II)-pyridine-dimethylglyoxime complex

    Energy Technology Data Exchange (ETDEWEB)

    Arya, S. P.; Mahajan, M. [Haryana, Kurukshetra Univ. (India). Dept. of Chemistry

    1998-05-01

    A simple and rapid spectrophotometric method for the determination of ascorbic acid is proposed. Ascorbic acid reduces iron (III) to iron (II) which forms a red colored complex with dimethylglyoxime in the presence of pyridine. The absorbance of the resulting solution is measured at 514 nm and a linear relationship between absorbance and concentration of ascorbic acid is observed up to 14 {mu}g ml{sup -1}. Studies on the interference of substances usually associated with ascorbic acid have been carried out and the applicability of the method has been tested by analysing pharmaceutical preparations of vitamin C. [Italiano] Si propone un rapido e semplice metodo spettrofotometrico per la determinazione dell`acido ascorbico. L`acido ascorbico riduce il ferro(III) a ferro(II) che forma con la dimetilgliossima, in presenza di piridina, un complesso colorato in rosso. L`assorbanza della soluzione risultante e` misurata a 514 nm e si ottiene una relazione lineare tra assorbanza e concentrazione dell`acido ascorbico fino a 14 {mu}g ml{sup -1}. Si sono condotti studi sugli interferenti usualmente associati all`acido ascorbico ed e` stata valutata l`applicabilita` del metodo all`analisi di preparati farmaceutici di vitamina C.

  15. Stability in fish feed and bioavailability to rainbow trout of two ascorbic acid forms

    DEFF Research Database (Denmark)

    Skelbaek, T.; Andersen, Niels Gerner; Winning, M.

    1990-01-01

    The stability in warm pelleted fish feed and the bioavailability to rainbow trout of crystalline ascorbic acid (AA) and a synthetic polymer-coated AA product (PCAA) were compared. The AA loss during pelleting was 29% for crystalline AA and 19% for PCAA. After 6 weeks at room temperature 73% of PCAA...

  16. Plasma ascorbic acid, a priori diet quality score, and incident hypertension

    NARCIS (Netherlands)

    Buijsse, Brian; Jacobs, D.R.; Steffen, L.M.; Kromhout, Daan; Gross, M.D.

    2015-01-01

    Vitamin C may reduce risk of hypertension, either in itself or by marking a healthy diet pattern. We assessed whether plasma ascorbic acid and the a priori diet quality score relate to incident hypertension and whether they explain each other's predictive abilities. Data were from 2884 black and

  17. Interference-Blind Microfluidic Sensor for Ascorbic Acid Determination by UV/vis Spectroscopy

    DEFF Research Database (Denmark)

    Bi, Hongyan; Oliveira Fernandes, Ana Carolina; Cardoso, Susana

    2016-01-01

    the microfluidic channel, enzyme-catalyzed reaction occurs and only converts the target molecules to its products. The whole process is monitored by an end-channel UV/vis spectroscopic detection. Ascorbate oxidase and L-ascorbic acid (AA) are taken as enzyme-substrate model in this study to investigate...... microfluidic biosensor exhibits good reproducibility, stability, and anti-interference property. Technically, it is easy to realize, depends on low investment in chip fabrication, and simple instrumental procedure, where only UV/vis spectrophotometer is required. To sum up, the developed strategy is economical...

  18. Ascorbic acid improves impaired venous and arterial endothelium dependent dilation in smokers

    Institute of Scientific and Technical Information of China (English)

    Márcio Gon(c)alves de SOUSA; Juan Carlos YUGAR-TOLEDO; Marcelo RUBIRA; Sílvia Elaine FERREIRA-MELO; Rodrigo PLENTZ; Deise BARBIERI; Fernanda CONSOLIM-COLOMBO; Maria Cláudia IRIGOYEN; Heitor MORENO Jr

    2005-01-01

    Aim: To compare the acute effects of ascorbic acid on vasodilation of veins and arteries in vivo. Methods: Twenty-six healthy non-smokers and 23 healthy moderate smokers were recruited in this study. The dorsal hand vein compliance technique and flow-mediated dilation were used. Dose-response curves to bradykinin and sodium nitroprusside were constructed to test the endothelium-dependent and -independent relaxation before and after acute infusion of ascorbic acid. Results: Smokers had an impaired venodilation with bradykinin compared with non-smokers (68.3%±13.2% vs 93.7%±20.1%, respectively; P<0.05). Ascorbic acid administration in the dorsal hand vein significantly increased the venodilation with bradykinin in smokers (68.3%± 13.2% vs 89.5%±6.3% before and after infusion, respectively; P<0.05) but not in non-smokers (93.7%±20.1% vs 86.4%±12.4% before and after infusion, respectively). Similarly, the arterial response in smokers had an impaired endothelium-dependent dilation compared with that in non-smokers (8.8%±2.7% vs 15.2%±2.3%, respectively; P<0.05) and ascorbic acid restored this response in smokers (8.8%±2.7% vs 18.7%±6.5% before and after infusion, respectively; P<0.05), but no difference was seen in non-smokers (15.2%±2.3% vs 14.0%±4.4% before and after infusion, respectively). The endothelium-independent dilation did not differ in both the groups studied. No important hemodynamic change was detected using the Portapress device. Conclusion: Smokers had impaired endothelium-dependent vasodilation responsiveness in both arterial and venous systems. Ascorbic acid restores this responsiveness in smokers.

  19. SKIN PERMEATION ENHANCEMENT EFFECTS OF ASCORBIC ACID AND TRIETHYL CITRATE ON ROFECOXIB

    Directory of Open Access Journals (Sweden)

    MALAY K. DAS

    2008-01-01

    Full Text Available The enhancing effect of ascorbic acid and triethyl citrate (TEC on the in vitro skin permeation of rofecoxib across rat epidermis was investigated. Skin pre-treatment with ascorbic acid and TEC at different concentrations, followed by application of rofecoxib gel, showed higher permeation flux than the control condition. The mechanism underlying this permeation enhancement was probed with fourier transform infrared spectroscopy (FTIR. The FTIR spectra of rat epidermis treated with ascorbic acid revealed that ascorbic acid at low concentration appears to interact with dermal keratin, whereas at higher concentration it appears to interact with both dermal proteins and lipids. The FTIR spectra of rat epidermis treated with TEC showed a decrease in peak heights for both asymmetric and symmetric C-H stretching absorbance, indicating a change in the fluidity of alkyl chains in the intercellular lipids in the stratum corneum (SC. The protein disruption effect of TEC was probably due to the solvation of keratin by the formation of hydrogen bonds between TEC hydroxyl groups and keratin chain C=O groups. Skin pre-treatment with different concentrations of permeation enhancers did not show any significant change in lag time in comparison to control. The amount of rofecoxib retained in the skin after skin pre-treatment with enhancers was found to be higher than in the experiment without skin pre-treatment. Scanning electron microscopy (SEM confirmed the maintenance of skin integrity throughout the permeation experiment. The observed permeation enhancing effects of ascorbic acid and TEC in the present study indicate that a rapid percutaneous absorption of rofecoxib at effective therapeutic levels may facilitate faster anti-inflammatory activity.

  20. Osteoblast protects osteoclast devoid of sodium-dependent vitamin C transporters from oxidative cytotoxicity of ascorbic acid.

    Science.gov (United States)

    Takarada, Takeshi; Hinoi, Eiichi; Kambe, Yuki; Sahara, Koichi; Kurokawa, Shintaro; Takahata, Yoshifumi; Yoneda, Yukio

    2007-12-01

    The view that ascorbic acid indirectly benefits osteoclastogenesis through expression of receptor activator of nuclear factor-kappaB (NF-kappaB) ligand (RANKL) by osteoblasts is prevailing. In this study, we have examined the direct effect of ascorbic acid on osteoclastogenesis in cultured mouse osteoclasts differentiated from bone marrow precursors. The absence of alkaline phosphatase and osteoblastic marker genes validated the usefulness of isolation procedures. Sustained exposure to ascorbic acid, but not to dehydroascorbic acid, significantly reduced the number of multinucleated cells positive to tartrate-resistant acid phosphatase (TRAP) staining. In cultured osteoclasts, mRNA expression was seen for glucose transporter-1 involved in membrane transport of dehydroascorbic acid, but not for sodium-dependent vitamin C transporters-1 and -2 that are both responsible for the transport of ascorbic acid. The inhibition by ascorbic acid was completely prevented by catalase, while ascorbic acid or hydrogen peroxide drastically increased the number of cells stained with propidium iodide and the generation of reactive oxygen species, in addition to inducing mitochondrial membrane depolarization in cultured osteoclasts. In pre-osteoclastic cell line RAW264.7 cells, ascorbic acid similarly inhibited the formation of TRAP-positive multinucleated cells, with a significant decrease in RANKL-induced NF-kappaB transactivation. Moreover, co-culture with osteoblastic MC3T3-E1 cells significantly prevented the ascorbic acid-induced decrease in the number of TRAP-positive multinucleated cells in RAW264.7 cells. These results suggest that ascorbic acid may play a dual repulsive role in osteoclastogenesis toward bone remodeling through the direct cytotoxicity mediated by oxidative stress to osteoclasts, in addition to the indirect trophism mediated by RANKL from osteoblasts.

  1. Fruit antioxidant activity, ascorbic acid, total phenol, quercetin, and carotene of Irwin mango fruits stored at low temperature after high electric field pretreatment.

    Science.gov (United States)

    Shivashankara, K S; Isobe, Seiichiro; Al-Haq, Muhammad Imran; Takenaka, Makiko; Shiina, Takeo

    2004-03-10

    Greenhouse-grown tree ripe (TR) and mature green (MG) mangoes (cv. Irwin) were exposed to high electric field treatment before 20 and 30 days of storage at 5 degrees C. MG fruits were allowed to ripen at room temperature after low-temperature storage. Fruit physical quality attributes, ascorbic acid, carotene, quercetin, total phenols, and antioxidant capacity were estimated before and after the storage period. Antioxidant capacity of fruit juice was estimated using the ferric reducing antioxidant power (FRAP) assay. Fruit firmness decreased significantly during storage. Titratable acidity decreased 20 days after storage. Total soluble solids did not change during storage. Antioxidant capacity of fruits remained unchanged up to 20 days of storage period and decreased thereafter. Total phenol and carotenes increased during storage. Antioxidant capacity of fruits was significantly correlated only to ascorbic acids. Peel color and carotenes were higher in TR fruits, whereas titratable acidity and firmness were higher in MG fruits. There was no significant difference in other parameters between the stages of picking. Electric field pretreatment affected the respiration and antioxidant capacity of TR fruits and did not have any significant affect on other parameters. TR mangoes of cv. Irwin are more suitable for low-temperature storage and can be successfully stored for up to 20 days at 5 degrees C without any significant losses in functional properties and quality attributes.

  2. Investigation of L(+)-Ascorbic Acid with Raman Spectroscopy in Visible and UV Light

    DEFF Research Database (Denmark)

    Berg, Rolf W.

    2015-01-01

    Abstract: Raman spectroscopy investigations of l(+)-ascorbic acid and its mono- and di-deprotonated anions (AH(-) and A(2-)) are reviewed and new measurements reported with several wavelengths, 229, 244, 266, 488, and 532nm. Results are interpreted, assisted by new DFT/B3LYP quantum chemical calc......). Relatively weak preresonance enhancement was seen for A(2-) when excitation was done with 229nm UV light, allowing water bands to become observable as for normal visible light Raman spectra....... calculations with 6-311++G(d,p) basis sets for several conformations of ascorbic acid and the anions. Raman spectra were measured during titration with NaOH base in an oxygen-poor environment to avoid fluorescence when solutions were alkaline. The ultraviolet (UV) absorption band for ascorbic acid in aqueous......cm(-1). Finally, for the ascorbate di-anion, absorption was found at similar to 298.4nm with molar absorptivity of similar to 7,000 L mol(-1) cm(-1) and below similar to 220nm. With UV light (244 and 266nm), strongly basic solutions gave pronounced Raman resonance enhancement at similar to 1556cm(-1...

  3. Effect of fermentation and subsequent pasteurization processes on amino acids composition of orange juice.

    Science.gov (United States)

    Cerrillo, I; Fernández-Pachón, M S; Collado-González, J; Escudero-López, B; Berná, G; Herrero-Martín, G; Martín, F; Ferreres, F; Gil-Izquierdo, A

    2015-06-01

    The fermentation of fruit produces significant changes in their nutritional composition. An orange beverage has been obtained from the controlled alcoholic fermentation and thermal pasteurization of orange juice. A study was performed to determine the influence of both processes on its amino acid profile. UHPLC-QqQ-MS/MS was used for the first time for analysis of orange juice samples. Out of 29 amino acids and derivatives identified, eight (ethanolamine, ornithine, phosphoethanolamine, α-amino-n-butyric acid, hydroxyproline, methylhistidine, citrulline, and cystathionine) have not previously been detected in orange juice. The amino acid profile of the orange juice was not modified by its processing, but total amino acid content of the juice (8194 mg/L) was significantly increased at 9 days of fermentation (13,324 mg/L). Although the pasteurization process produced partial amino acid degradation, the total amino acid content was higher in the final product (9265 mg/L) than in the original juice, enhancing its nutritional value.

  4. Stabilization of anthocyanins in blackberry juice by glutathione fortification.

    Science.gov (United States)

    Stebbins, Nathan B; Howard, Luke R; Prior, Ronald L; Brownmiller, Cindi; Mauromoustakos, Andy

    2017-09-06

    Blackberry anthocyanins provide attractive color and antioxidant activity. However, anthocyanins degrade during juice processing and storage, so maintaining high anthocyanin concentrations in berry juices may lead to greater antioxidant and health benefits for the consumer. This study evaluated potential additives to stabilize anthocyanins during blackberry juice storage. The anthocyanin stabilizing agents used were: glutathione, galacturonic acid, diethylenetriaminepentaacetic acid and tannic acid, which were added at a level of 500 mg L(-1). Juice anthocyanin, flavonol, and ellagitannin content and percent polymeric color were measured over five weeks of accelerated storage at 30 °C. Glutathione had the greatest protective effect on total anthocyanins and polymeric color. Therefore a second study was performed with glutathione in combination with lipoic and ascorbic acids in an effort to use antioxidant recycling to achieve a synergistic effect. However, the antioxidant recycling system had no protective effect relative to glutathione alone. Glutathione appears to be a promising blackberry juice additive to protect against anthocyanin degradation during storage.

  5. The effects of fruit juices and fruits on the absorption of iron from a rice meal.

    Science.gov (United States)

    Ballot, D; Baynes, R D; Bothwell, T H; Gillooly, M; MacFarlane, B J; MacPhail, A P; Lyons, G; Derman, D P; Bezwoda, W R; Torrance, J D

    1987-05-01

    The effects of the chemical composition of fruit juices and fruit on the absorption of iron from a rice (Oryza sativa) meal were measured in 234 parous Indian women, using the erythrocyte utilization of radioactive Fe method. The corrected geometric mean Fe absorptions with different juices varied between 0.040 and 0.129, with the variation correlating closely with the ascorbic acid contents of the juices (rs 0.838, P less than 0.01). Ascorbic acid was not the only organic acid responsible for the promoting effects of citrus fruit juices on Fe absorption. Fe absorption from laboratory 'orange juice' (100 ml water, 33 mg ascorbic acid and 750 mg citric acid) was significantly better than that from 100 ml water and 33 mg ascorbic acid alone (0.097 and 0.059 respectively), while Fe absorption from 100 ml orange juice (28 mg ascorbic acid) was better than that from 100 ml water containing the same amount of ascorbic acid (0.139 and 0.098 respectively). Finally, Fe absorption from laboratory 'lemon juice' (100 ml orange juice and 4 g citric acid) was significantly better than that from 100 ml orange juice (0.226 and 0.166 respectively). The corrected geometric mean Fe absorption from the rice meal was 0.025. Several fruits had little or no effect on Fe absorption from the meal (0.013-0.024). These included grape (Vitis vinifera), peach (Prunus persica), apple (Malus sylvestris) and avocado pear (Persea americana). Fruit with a mild to moderate enhancing effect on Fe absorption (0.031-0.088) included strawberry (Fragaria sp.) (uncorrected values), plum (Prunus domestica), rhubarb (Rheum rhaponticum), banana (Musa cavendishii), mango (Mangifera indica), pear (Pyrus communis), cantaloup (Cucumis melo) and pineapple (Ananas comosus) (uncorrected values). Guava (Psidium guajava) and pawpaw (Carica papaya) markedly increased Fe absorption (0.126-0.293). There was a close correlation between Fe absorption and the ascorbic acid content of the fruits tested (rs 0.738, P less

  6. Comparison of bioactive components in pressurized and pasteurized longan juices fortified with encapsulated Lactobacillus casei 01

    Science.gov (United States)

    Chaikham, Pittaya; Apichartsrangkoon, Arunee

    2012-06-01

    In this study, longan juice was subjected to a high pressure of 500 MPa for 30 min and compared with a juice pasteurized at 90°C/2 min. Probiotic Lactobacillus casei 01 was fortified into both juices and the shelf life of these products was studied. Their bioactive components such as ascorbic acid, gallic acid and ellagic acid were analyzed by High Performance Liquid Chromatography (HPLC). Total phenolic compounds and 2,2-Diphenyl-1-picrythydrazyl radical-scavenging activity were determined by colorimetric and spectrophotometric methods. It was found that the pressurized longan juice retained higher amounts of bioactive compounds than the pasteurized juice. In terms of storage stability, bioactive compounds in both processed juices decreased according to the increase in storage time. The survivability of probiotic L. casei 01 in both processed juices declined from 9 to 6 log CFU/mL after 4 weeks of storage.

  7. Catalytic protection of stannous ion by ascorbic acid in diphosphonic acids solutions

    Institute of Scientific and Technical Information of China (English)

    LiuGuo-Zheng; LiuFei; 等

    1998-01-01

    The protective ability of ascorbic acid(Vc) on stannous ion and the influence of light irradiation on the stability of stannous ion in diphosphonate medium at pH=5 have been examined in order to attain minimal loss of stannous ion during the production of lyophilized radiopharmaceutical kits.The sum of stanous ion and Vc was determined with iodometric method.It was shown that the protective ability of Vc was still strong at Vc concentration much lower than that of stannous ion and the illumination by fluorescent lamp was unfavorable to the stability of stannous ion.The change of pH in the range 3-9 did not affect the action of Vc significantly.

  8. [Ascorbic acid consumption and serum levels in smokers and non-smokers adult men in Hermosillo, Sonora, México].

    Science.gov (United States)

    Méndez, Rosa Olivia; Wyatt, C Jane; Saavedra, Javier; Ornelas, Alicia

    2002-12-01

    Ascorbic acid is one of the important antioxidant nutrients that can aid in the prevention of oxidative cellular damage. Adequate dietary intake is essential as humans can not synthesize this vitamin. It has been reported that smokers require higher dietary intakes to maintain their serum levels. The objective of this study was to determine serum levels of ascorbic acid in young male smokers and non smokers in the city of Hermosillo, Sonora, Mexico. In addition, their dietary intake of ascorbic acid was determined by a 24 h dietary recall. The dietary intake of ascorbic acid in 12 smokers was 64 +/- 11 mg/d and in 13 non smokers it was 70 +/- 12 mg/d. The smokers in this study did not meet the dietary recommendation of 100 mg/d. Serum ascorbic acid values in smokers and non smokers were 24.2 +/- 6.9 mumol/L and 30.9 +/- 3.7 mumol/L respectively. No significant difference was found among the 2 groups. Although the average serum ascorbic acid values fell within the range considered normal, 50% of the smokers had individual values that were below 23 mumol/L, indicating that these subjects have hipovitaminosis. A positive correlation between intake and serum levels was obtained for smokers (r = 0.71; p = 0.03). The results of this study suggest smokers may be at increased risk for chronic diseases due to their low intake and low serum levels of ascorbic acid.

  9. Electrochemicla Behavior of Ascorbic Acid on Hexaaza Macrocyclic Copper(II) Complex Modified Au Electrode and Its Analytical Application

    Institute of Scientific and Technical Information of China (English)

    WU,Hai-Xia; DONG,Shu-Qing; KANG,Jing-Wan; LU,Xiao-Quan

    2008-01-01

    A novel hexaaza macrocyclic copper(II) complex modified Au electrode was developed and used for the measurement of ascorbic acid. Its electrochemical behavior was investigated by cyclic voltammetry and scanning electrochemical microscopy. This modified electrode exhibited electrocatalytic response to the oxidation of ascorbic acid. Compared with a bare gold electrode, the modified electrode exhibited a 250 mV shift of the oxidation potential of ascorbic acid in the cathodic direction and a marked enhancement of the current response. The response current revealed a good linear relationship with the concentration of ascorbic acid in the range of 5.0×10-7 to 4.0× 10-5 mol/L and the detection limit of 4.8× 10-8 mol/L (S/N=3) in the pH 4.0 Tris-HCl buffer of ascorbic acid in fruits without any other pretreatment. The concentrations of ascorbic acid measured by this method were in good agreement with the literature values. It is very promising for the modified electrode to be used as an electrochemical sensor for the detection of ascorbic acid.

  10. An ascorbic acid-enriched tomato genotype to fight UVA-induced oxidative stress in normal human keratinocytes.

    Science.gov (United States)

    Petruk, Ganna; Raiola, Assunta; Del Giudice, Rita; Barone, Amalia; Frusciante, Luigi; Rigano, Maria Manuela; Monti, Daria Maria

    2016-10-01

    UVA radiations contribute up to 95% of the total UV exposure and are known to induce cell damage, leading to apoptosis. Since the benefic effects of ascorbic acid on human health are well known, a new tomato genotype (named DHO4), highly rich in ascorbic acid, has been recently obtained. Here, we compared the effects of ascorbic acid and hydrophilic DHO4 extracts in protecting human keratinocytes exposed to UVA stress. Keratinocytes were pre-incubated with ascorbic acid or with extracts from the ascorbic acid enriched tomato genotype and irradiated with UVA light. Then, ROS production, intracellular GSH and lipid peroxidation levels were quantified. Western blots were carried out to evaluate mitogen-activated protein kinases cascade, activation of caspase-3 and inflammation levels. We demonstrated that ROS, GSH and lipid peroxidation levels were not altered in cell exposed to UVA stress when cells were pre-treated with ascorbic acid or with tomato extracts. In addition, no evidence of apoptosis and inflammation were observed in irradiated pre-treated cells. Altogether, we demonstrated the ability of an ascorbic acid enriched tomato genotype to counteract UVA-oxidative stress on human keratinocytes. This protective effect is due to the high concentration of vitamin C that acts as free radical scavenger. This novel tomato genotype may be used as genetic material in breeding schemes to produce improved varieties with higher antioxidant levels.

  11. Application of 10% Ascorbic Acid Improves Resin Shear Bond Stregth in Bleached Dentin

    Directory of Open Access Journals (Sweden)

    Kamizar Kamizar

    2014-10-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Restoration of the teeth immediately after bleaching with H2O2 35% is contraindicated due to the remnants of free radical that will stay inside dentin for 2-3 weeks which will compromise the adhesiveness of composite resin. Objective: The aim of this study was to evaluate the influence of 10% ascorbic acid on shear bond strength of composite placed on bleached dentin. Methods:Twenty seven samples were divided equally into three groups. Group 1: dentin was etched with 35% phosphoric acid; Group 2: dentin was bleached with 35% H2O2 followed by etching with 35% phosphoric acid; Group 3: dentin was bleached with 35% H2O2, followed by application of 10% ascorbic acid and etched with 35% phosphoric acid. All samples were then stored at 370C for 24 hours. The Universal Testing Machine was used to measure shear bond strength and the results were analyzed with Kruskal Wallis and Mann Whitney test. Results: After nine independent experiments, 10% ascorbic acid application on bleached dentin resulted in highest increased in bond stregth (56.04±11.06MPa compared to Group 2 (29.09±7.63MPa and Group 1 (25.55±2.22MPa and the difference was statistically significant (p<0.05. Conclusion: Application of 10% ascorbic acid to the bleached dentin improved the shear bond strength of resin composite.

  12. New vegetable and fruit-vegetable juices treated by high pressure

    Science.gov (United States)

    Gabrovská, Dana; Ouhrabková, Jarmila; Rysová, Jana; Laknerová, Ivana; Fiedlerová, Vlasta; Holasová, Marie; Winterová, Renata; Průchová, Jiřina; Strohalm, Jan; Houška, Milan; Landfeld, Aleš; Erban, Vladimír; Eichlerová, Eva; Němečková, Irena; Kejmarová, Marie; Bočková, Pavlína

    2012-03-01

    The aim of this work was to find sensory suitable combinations of not commonly used vegetables, that is, cabbage, celeriac and parsnip, into mixed fruit-vegetable juices, two-species vegetable juices and vegetable juices with whey. These juices might have the potential to offer consumers new, interesting, tasty and nutritional products. Another interesting variation could be preparation of vegetable juices in combination with sweet whey. Nutritional and sensory evaluations were carried out using juices prepared in the laboratory. The total phenolic content, in addition to ascorbic acid and antioxidant activity, was determined. The developed juices with high nutritional value should increase very low fruit and vegetable consumption in the Czech population. The prepared juices were high pressure pasteurized (410 MPa). This technique retains the desired levels of important nutritional substances, while being destructive to live microbial cell structure. The germination of spores is suppressed by low pH value.

  13. Ascorbic Acid Promotes the Stemness of Corneal Epithelial Stem/Progenitor Cells and Accelerates Epithelial Wound Healing in the Cornea.

    Science.gov (United States)

    Chen, Jialin; Lan, Jie; Liu, Dongle; Backman, Ludvig J; Zhang, Wei; Zhou, Qingjun; Danielson, Patrik

    2017-03-09

    High concentration of ascorbic acid (vitamin C) has been found in corneal epithelium of various species. However, the specific functions and mechanisms of ascorbic acid in the repair of corneal epithelium are not clear. In this study, it was found that ascorbic acid accelerates corneal epithelial wound healing in vivo in mouse. In addition, ascorbic acid enhanced the stemness of cultured mouse corneal epithelial stem/progenitor cells (TKE2) in vitro, as shown by elevated clone formation ability and increased expression of stemness markers (especially p63 and SOX2). The contribution of ascorbic acid on the stemness enhancement was not dependent on the promotion of Akt phosphorylation, as concluded by using Akt inhibitor, nor was the stemness found to be dependent on the regulation of oxidative stress, as seen by the use of two other antioxidants (GMEE and NAC). However, ascorbic acid was found to promote extracellular matrix (ECM) production, and by using two collagen synthesis inhibitors (AzC and CIS), the increased expression of p63 and SOX2 by ascorbic acid was decreased by around 50%, showing that the increased stemness by ascorbic acid can be attributed to its regulation of ECM components. Moreover, the expression of p63 and SOX2 was elevated when TKE2 cells were cultured on collagen I coated plates, a situation that mimics the in vivo situation as collagen I is the main component in the corneal stroma. This study shows direct therapeutic benefits of ascorbic acid on corneal epithelial wound healing and provides new insights into the mechanisms involved. © Stem Cells Translational Medicine 2017.

  14. Effect of ascorbic acid supplementation on nitric oxide metabolites and systolic blood pressure in rats exposed to lead.

    Science.gov (United States)

    Mohammad, Amani; Ali, Noroozzadeh; Reza, Badalzadeh; Ali, Khoshbaten

    2010-04-01

    Extended exposure to low levels of lead causes high blood pressure in human and laboratory animals. The mechanism is not completely recognized, but it is relatively implicated with generation of free radicals, oxidant agents such as ROS, and decrease of available nitric oxide (NO). In this study, we have demonstrated the effect of ascorbic acid as an antioxidant on nitric oxide metabolites and systolic blood pressure in rats exposed to low levels of lead. The adult male Wistar rats weighing 200-250 g were divided into four groups: control, lead acetate (receiving 100 ppm lead acetate in drinking water), lead acetate plus ascorbic acid (receiving 100 ppm lead acetate and 1 g/l ascorbic acid in drinking water), and ascorbic acid (receiving 1 g/l ascorbic acid in drinking water) groups. The animals were anesthetized with ketamin/xylazine (50 and 7 mg/kg, respectively, ip) and systolic blood pressure was then measured from the tail of the animals by a sphygmomanometer. Nitric oxide levels in serum were measured indirectly by evaluation of its stable metabolites (total nitrite and nitrate (NOchi)). After 8 and 12 weeks, systolic blood pressure in the lead acetate group was significantly elevated compared to the control group. Ascorbic acid supplementation could prevent the systolic blood pressure rise in the lead acetate plus ascorbic acid group and there was no significant difference relative to the control group. The serum NOchi levels in lead acetate group significantly decreased in relation to the control group, but this reduction was not significantly different between the lead acetate plus ascorbic acid group and the control group. Results of this study suggest that ascorbic acid as an antioxidant prevents the lead induced hypertension. This effect may be mediated by inhibition of NOchi oxidation and thereby increasing availability of NO.

  15. Effect of ascorbic acid supplementation on nitric oxide metabolites and systolic blood pressure in rats exposed to lead

    Directory of Open Access Journals (Sweden)

    Mohammad Amani

    2010-01-01

    Full Text Available Background: Extended exposure to low levels of lead causes high blood pressure in human and laboratory animals. The mechanism is not completely recognized, but it is relatively implicated with generation of free radicals, oxidant agents such as ROS, and decrease of available nitric oxide (NO. In this study, we have demonstrated the effect of ascorbic acid as an antioxidant on nitric oxide metabolites and systolic blood pressure in rats exposed to low levels of lead. Materials and Methods: The adult male Wistar rats weighing 200-250 g were divided into four groups: control, lead acetate (receiving 100 ppm lead acetate in drinking water, lead acetate plus ascorbic acid (receiving 100 ppm lead acetate and 1 g/l ascorbic acid in drinking water, and ascorbic acid (receiving 1 g/l ascorbic acid in drinking water groups. The animals were anesthetized with ketamin/xylazine (50 and 7 mg/kg, respectively, ip and systolic blood pressure was then measured from the tail of the animals by a sphygmomanometer. Nitric oxide levels in serum were measured indirectly by evaluation of its stable metabolites (total nitrite and nitrate (NOc. Results: After 8 and 12 weeks, systolic blood pressure in the lead acetate group was significantly elevated compared to the control group. Ascorbic acid supplementation could prevent the systolic blood pressure rise in the lead acetate plus ascorbic acid group and there was no significant difference relative to the control group. The serum NOc levels in lead acetate group significantly decreased in relation to the control group, but this reduction was not significantly different between the lead acetate plus ascorbic acid group and the control group. Conclusion: Results of this study suggest that ascorbic acid as an antioxidant prevents the lead induced hypertension. This effect may be mediated by inhibition of NOc oxidation and thereby increasing availability of NO.

  16. Methane formation by oxidation of ascorbic acid using iron minerals and hydrogen peroxide.

    Science.gov (United States)

    Althoff, Frederik; Jugold, Alke; Keppler, Frank

    2010-06-01

    The possibility of methane formation in an oxidative environment has been intensely debated, especially since the discovery of methane generation by living plants. However, recent studies with animal tissue suggested that under specific conditions aerobic methane formation is also possible. Here, we investigated the generation of methane in an abiotic model system using bioavailable substances. We show formation of methane in a highly oxidative media, using ascorbic acid, ferrihydrite and hydrogen peroxide as reagents. Methane production was shown to be related to reagent ratio, reaction volume and pH. A 2:1 ratio of hydrogen peroxide to ascorbic acid, catalytic amounts of ferrihydrite and acidic conditions (pH 3) enhanced formation of methane. We further show that gaseous oxygen has a strong influence with higher levels found to inhibit methane formation. This study is a first step towards providing an insight for the reaction mechanism of methane formation that would be applicable to aerobic environments.

  17. Ascorbic-acid-assisted recovery of cobalt and lithium from spent Li-ion batteries

    Science.gov (United States)

    Li, Li; Lu, Jun; Ren, Yang; Zhang, Xiao Xiao; Chen, Ren Jie; Wu, Feng; Amine, Khalil

    2012-11-01

    Recycling of the major components from spent Li-ion batteries (LIBs) is considered desirable to prevent environmental pollution and recycle valuable metals. The present work investigates a novel process for recovering Co and Li from the cathode materials (containing LiCoO2 and Al) by a combination of ultrasonic washing, calcination, and organic acid leaching. Copper can also be recovered from the anode materials after they are manually separated from the cathode. Ascorbic acid is chosen as both leaching reagent and reducing agent to improve the Co recovery efficiency. Leaching efficiencies as high as 94.8% for Co and 98.5% for Li are achieved with a 1.25 mol L-1 ascorbic acid solution, leaching temperature of 70 °C, leaching time of 20 min, and solid-to-liquid ratio of 25 gL-1. The acid leaching reaction mechanism has been preliminarily studied based on the structure of ascorbic acid. This method is shown to offer an efficient way to recycle valuable materials from spent LIBs, and it can be scaled up for commercial application.

  18. Ascorbic acid as a bifunctional hydrogen bond donor for the synthesis of cyclic carbonates from CO2 under ambient conditions

    KAUST Repository

    Arayachukiat, Sunatda

    2017-07-14

    Readily available ascorbic acid was discovered as an environmentally benign hydrogen bond donor (HBD) for the synthe-sis of cyclic organic carbonates from CO2 and epoxides in the presence of nucleophilic co-catalysts. The ascorbic acid/TBAI (TBAI: tetrabutylammonium iodide) binary system could be applied for the cycloaddition of CO2 to various epoxides under ambient or mild conditions. DFT calculations and catalysis experiments revealed an intriguing bifunctional mechanism in the step of CO2 insertion involving different hydroxyl moieties (enediol, ethyldiol) of the ascorbic acid scaffold.

  19. Effects of ascorbic acid on cell mediated, humoral immune response and pathophysiology of

    Directory of Open Access Journals (Sweden)

    Suchint Simaraks

    2003-05-01

    Full Text Available The purpose of this study was to conduct an experiment related to the effects of chronic heat stress on total white blood cell changes, pathophysiology of leukocyte and effects of ascorbic acid on lymphocytes, lympholytic cells and humoral immunity of New-castle disease of broilers under chronic heat stress. Randomized complete block was the design. One hundred-forty-four chickens were maintained at 33+1 oC environmental temperature and on four levels of added ascorbic acid i.e. 0 (control group, 200, 400 and 800 mg/kg in dietsfor 21 days. On days 1, 3, 7, 14 and 21 of the experimental period, total white blood cells count, lympholytic cell and HI titer for Newcastle disease were determined. On day 21, histopathology of lung, liver, kidney, heart and bursa of fabricius of randomly selected broilers (n=36; 3 birds per experimental unit were studied. Total white blood cells (TWBC of the birds were significantly increased on day 3 (P<0.05 and were higheston days 7 and 14 then significantly decreased on days 21 (P<0.05. Monocytes were significantly increased on day 3 (P<0.05. Lymphocytes were significantly increased on day 7, and were highest on day 14 (P<0.05. On day 21, the value of lymphocyte was significantly lower than on days 7 and 14 (P<0.05, respectively. Lympholytic cells were significantly increased on day 3 and 7 (P<0.05, respectively, but on day 21, lympholyticcells were significantly decreased to lower value than on day 7 (P<0.05. Heterophils were significantly increased on day 3 and 7 and then decreased on day 14 (P<0.05. Tissue injury and hemorrhage in broilers under chronic heat stress caused leukocytosis, heterophilia, lympholysis and monocytosis. The size of lobules within the bursa of fabricius in broilers receiving ascorbic acid at 800 mg/kg in the diet were larger than inbirds that received added ascorbic acid at 400, 200 and 0 mg/kg in their diets, respectively. Lymphocytes and lympholytic cells were not significantly different

  20. Topical activity of ascorbic acid: from in vitro optimization to in vivo efficacy.

    Science.gov (United States)

    Raschke, T; Koop, U; Düsing, H-J; Filbry, A; Sauermann, K; Jaspers, S; Wenck, H; Wittern, K-P

    2004-01-01

    We present here a new cosmetic formula system containing 3% ascorbic acid based on an optimized oil-in-water (O/W) emulsion. This formulation demonstrated a good long-term stability of the active ingredient and also of the emulsion itself. It could be deduced from in vitro release studies that this O/W emulsion enabled a better release of the hydrophilic active agent than an alternative W/O emulsion. By measuring the ultraweak photon emission, which is a well-established parameter for the oxidative stress in the skin, the high in vivo antioxidant capacity of 3% ascorbic acid was demonstrated after 1 week of product application. This placebo-controlled study also proved that ascorbic acid in an O/W cream reduced oxidative stress in human skin significantly better than the derivative sodium ascorbyl-2-phosphate, a more stable vitamin C replacement commonly used in cosmetic formulations. With increasing age, the number of papillae in the epidermal-dermal junction zone in human skin are reduced. This implies a possible consequence of reduced mechanical resistance of the skin and impaired supply of the epidermis with nutrients. In a 1-month placebo-controlled study on 25 human volunteers, a significant increase in the number of dermal papillae after application of the 3% ascorbic acid cream was demonstrated, using a confocal laser scanning microscope. Fine lines and wrinkles are a characteristic sign of aged and especially photo-aged skin. Application of 3% ascorbic acid in a 12-week placebo-controlled usage study indicated a significant reduction of facial wrinkles. Altogether, 3% ascorbic acid in a cosmetic O/W emulsion has been shown to be appropriately stable and to enable a good release of the active agent in vitro as a precondition for a high efficacy in vivo. Application in vivo resulted in a significant reduction of oxidative stress in the skin, an improvement of the epidermal-dermal microstructure and a reduction of fine lines and wrinkles in aged skin. These

  1. Nonenzymatic amperometric sensor for ascorbic acid based on hollow gold/ruthenium nanoshells

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Ara; Kang, Minkyung; Cha, Areum; Jang, Hye Su [Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Shim, Jun Ho [Department of Chemistry, Daegu University, Gyeongsan 712-714 (Korea, Republic of); Lee, Nam-Suk [National Center for Nanomaterials Technology (NCNT), Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Korea, Republic of); Kim, Myung Hwa [Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Lee, Youngmi, E-mail: youngmilee@ewha.ac.kr [Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Lee, Chongmok, E-mail: cmlee@ewha.ac.kr [Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750 (Korea, Republic of)

    2014-03-01

    Highlights: • We synthesized hollow gold/ruthenium (hAu–Ru) nanoshells for ascorbic acid sensing. • The hAu–Ru nanoshells showed sensitivity of 426 μA mM⁻¹ cm⁻² for ascorbic acid. • Good selectivity against glucose, uric acid, dopamine, 4-acetamidophenol, and NADH. • The linear dynamic range appeared from zero to 2.0 mM (R = 0.9995). • Response time (1.6 s) and low detection limit (2.2 μM) were obtained at pH 7.40. Abstract: We report a new nonenzymatic amperometric detection of ascorbic acid (AA) using a glassy carbon (GC) disk electrode modified with hollow gold/ruthenium (hAu–Ru) nanoshells, which exhibited decent sensing characteristics. The hAu–Ru nanoshells were prepared by the incorporation of Ru on hollow gold (hAu) nanoshells from Co nanoparticle templates, which enabled AA selectivity against glucose without aid of enzyme or membrane. The structure and electrocatalytic activities of the hAu–Ru catalysts were characterized by spectroscopic and electrochemical techniques. The hAu–Ru loaded on GC electrode (hAu–Ru/GC) showed sensitivity of 426 μA mM⁻¹ cm⁻² (normalized to the GC disk area) for the linear dynamic range of <5 μM to 2 mM AA at physiological pH. The response time and detection limit were 1.6 s and 2.2 μM, respectively. Furthermore, the hAu–Ru/GC electrode displayed remarkable selectivity for ascorbic acid over all potential biological interferents, including glucose, uric acid (UA), dopamine (DA), 4-acetamidophenol (AP), and nicotinamide adenine dinucleotide (NADH), which could be especially good for biological sensing.

  2. Analytical characterization of some pasteurized apple juices during storage

    Directory of Open Access Journals (Sweden)

    Damian Cristina

    2015-06-01

    Full Text Available The aim of the study was to assess the effect of three weeks of storage on the chemical and rheological properties of apple juices obtained from Idared and Jonatan apples variety. Total antioxidant activity, levels of bio-active compound groups and the viscosity were measured to characterize the investigated juices. The method applied for the determination of ascorbic acid concentration was with 2, 6-diclorophenolindophenol. Total phenols (TP in apple juices were determined using the Folin-Ciocalteau method and antioxidant activity by the use of DPPH free radical method. The viscosity of apple juices was investigated by a rotational viscometer, Brookfield viscometer (Brookfield Engineering Inc., Model RV-DV I Prime with RV spindles. During three weeks of storage, different rates of all measured properties have been observed decreasing for both studied apples varieties juices. The juices from Jonatan apples have higher antioxidant activities that are correlated with the higher content in polyphenols and lower values of viscosity.

  3. Routine sample preparation and HPLC analysis for ascorbic acid (vitamin C) determination in wheat plants and Arabidopsis leaf tissues.

    Science.gov (United States)

    Szalai, Gabriella; Janda, T; Pál, Magda

    2014-06-01

    Plants have developed various mechanisms to protect themselves against oxidative stress. One of the most important non-enzymatic antioxidants is ascorbic acid. There is thus a need for a rapid, sensitive method for the analysis of the reduced and oxidised forms of ascorbic acid in crop plants. In this paper a simple, economic, selective, precise and stable HPLC method is presented for the detection of ascorbate in plant tissue. The sensitivity, the short retention time and the simple isocratic elution mean that the method is suitable for the routine quantification of ascorbate in a high daily sample number. The method has been found to be better than previously reported methods, because of the use of an economical, readily available mobile phase, UV detection and the lack of complicated extraction procedures. The method has been tested on Arabidopsis plants with different ascorbate levels and on wheat plants during Cd stress.

  4. Uptake of dehydroascorbic acid and ascorbic acid to isolated nerve terminals and secretory granules from ox neurohypophyses

    DEFF Research Database (Denmark)

    Thorn, N A; Nielsen, F S; Jeppesen, C K

    1986-01-01

    When uptake of L-[14C]ascorbic acid ([14C]AA) to various organs in guinea-pigs was studied after intracardiac injection, the adenohypophysis, pars intermedia, and the neurohypophysis had an uptake per milligramme protein which was about half of the uptake to the adrenals. Adrenal uptake was 20...

  5. Structure, spectra and antioxidant action of ascorbic acid studied by density functional theory, Raman spectroscopic and nuclear magnetic resonance techniques.

    Science.gov (United States)

    Singh, Gurpreet; Mohanty, B P; Saini, G S S

    2016-02-15

    Structure, vibrational and nuclear magnetic resonance spectra, and antioxidant action of ascorbic acid towards hydroxyl radicals have been studied computationally and in vitro by ultraviolet-visible, nuclear magnetic resonance and vibrational spectroscopic techniques. Time dependant density functional theory calculations have been employed to specify various electronic transitions in ultraviolet-visible spectra. Observed chemical shifts and vibrational bands in nuclear magnetic resonance and vibrational spectra, respectively have been assigned with the help of calculations. Changes in the structure of ascorbic acid in aqueous phase have been examined computationally and experimentally by recording Raman spectra in aqueous medium. Theoretical calculations of the interaction between ascorbic acid molecule and hydroxyl radical predicted the formation of dehydroascorbic acid as first product, which has been confirmed by comparing its simulated spectra with the corresponding spectra of ascorbic acid in presence of hydrogen peroxide. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Structure, spectra and antioxidant action of ascorbic acid studied by density functional theory, Raman spectroscopic and nuclear magnetic resonance techniques

    Science.gov (United States)

    Singh, Gurpreet; Mohanty, B. P.; Saini, G. S. S.

    2016-02-01

    Structure, vibrational and nuclear magnetic resonance spectra, and antioxidant action of ascorbic acid towards hydroxyl radicals have been studied computationally and in vitro by ultraviolet-visible, nuclear magnetic resonance and vibrational spectroscopic techniques. Time dependant density functional theory calculations have been employed to specify various electronic transitions in ultraviolet-visible spectra. Observed chemical shifts and vibrational bands in nuclear magnetic resonance and vibrational spectra, respectively have been assigned with the help of calculations. Changes in the structure of ascorbic acid in aqueous phase have been examined computationally and experimentally by recording Raman spectra in aqueous medium. Theoretical calculations of the interaction between ascorbic acid molecule and hydroxyl radical predicted the formation of dehydroascorbic acid as first product, which has been confirmed by comparing its simulated spectra with the corresponding spectra of ascorbic acid in presence of hydrogen peroxide.

  7. Uptake of ascorbic acid by freshly isolated cells and secretory granules from the intermediate lobe of ox hypophyses

    DEFF Research Database (Denmark)

    Zhou, A; Matsumoto, T; Farver, O

    1990-01-01

    of uptake occurred when mechanically isolated cells were incubated with increasing ascorbic acid concentrations up to 0.6 mM. But if such cells were purified on a Percoll gradient, a clear saturation of uptake could be observed. Acetylsalicylic acid reduced the uptake markedly. When cells loaded with L-[14C......Mechanically isolated cells from the intermediate lobe of ox hypophyses contained 40.6 +/- 3.7 nmol mg-1 protein (mean +/- SE, n = 5) of ascorbic acid. They accumulated radioactivity time dependently, on incubation with L-[14C]ascorbic acid in ionic medium dominated by NaCl. No definite saturation......]ascorbic acid were homogenized and placed on a Percoll gradient, the radioactivity was recovered in several subcellular fractions. Decrease of the Na+ concentration or presence of ouabain in the medium did not cause noticeable changes in uptake by non-purified cells, whereas uptake by purified cells was clearly...

  8. Mechanism of Ascorbic Acid-induced Reversion Against Malignant Phenotype in Human Gastric Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    YA-XUAN SUN; QIU-SHENG ZHENG; GANG LI; DE-AN GUO; ZI-REN WANG

    2006-01-01

    Objective To find out the mechanisms of redifferentiation and reversion of malignant human gastric cancer cells induced by ascorbic acid. Methods Human gastric cancer cells grown in the laboratory were used. The Trypan blue dye exclusion method was used to determine the cell doubling time. The electrophoresis rate and colonogenic potential were the indices used to measure the rate of redifferentiation. The content of malondialdehyde (MDA) was measured using the thiobarbituric acid(TBA) method. The activities of superoxide dismutase (SOD), catalase (CAT) and the content of H2O2 were evaluated by spectrophotography. Results Six mmol/L ascorbic acid was used as a positive control. Human gastric cancer cells were treated with 75 μm hydrogen peroxide, which alleviated many of the malignant characteristics. For example, the cell surface charge obviously decreased and the electrophoresis rate dropped from 2.21 to 1.10 μm·s-1·V-1·cm-1. The colonogenic potential, a measure of cell differentiation, decreased 90.2%. After treatment with ascorbic acid, there was a concentration- and time-dependent increase in hydrogen peroxide (H2O2) and the activity of superoxide dismutase (SOD). However, the activity of catalase (CAT) resulted in a concentration- and time-dependent decrease. SOD and 3-amino-1,2,4-triazole (AT) exhibited some effects, but there were statistically significant differences between the SOD and AT group and the H2O2 group. Conclusions Ascorbic acid induces growth inhibition and redifferentiation of human gastric cancer cells through the production of hydrogen peroxide.

  9. L-dehydroascorbic acid can substitute L-ascorbic acid as dietary vitamin C source in guinea pigs

    DEFF Research Database (Denmark)

    Frikke-Schmidt, Henriette Rønne; Tveden-Nyborg, Pernille; Lykkesfeldt, Jens

    2016-01-01

    Vitamin C deficiency globally affects several hundred million people and has been associated with increased morbidity and mortality in numerous studies. In this study, bioavailability of the oxidized form of vitamin C (l-dehydroascorbic acid or DHA)-commonly found in vitamin C containing food...... products prone to oxidation-was studied. Our aim was to compare tissue accumulation of vitamin C in guinea pigs receiving different oral doses of either ascorbate or DHA. In all tissues tested (plasma, liver, spleen, lung, adrenal glands, kidney, muscle, heart, and brain), only sporadic differences...... in vitamin C accumulation from ascorbate or DHA were observed except for the lowest dose of DHA (0.25mg/ml in the drinking water), where approximately half of the tissues had slightly yet significantly less vitamin C accumulation than from the ascorbate source. As these results contradicted data from rats...

  10. Solubilities of magnesium-L-ascorbate, calcium-L-ascorbate, magnesium-L-glutamate, magnesium-D-gluconate, calcium-D-gluconate, calcium-D-heptagluconate, L-aspartic acid, and 3-nitrobenzoic acid in water

    Energy Technology Data Exchange (ETDEWEB)

    Mishelevich, Alexander [Department of Chemical Engineering, Ben Gurion University of the Negev, Beer Sheva 84105 (Israel); Apelblat, Alexander [Department of Chemical Engineering, Ben Gurion University of the Negev, Beer Sheva 84105 (Israel)], E-mail: apelblat@bgu.ac.il

    2008-05-15

    The solubility in water of magnesium-L-ascorbate, calcium-L-ascorbate, magnesium-L-glutamate, magnesium-D-gluconate, calcium-D-gluconate, calcium-D-heptagluconate, L-aspartic acid, and 3-nitrobenzoic acid was determined in the 278.15 K to 343.15 K temperature range. The solubility of these compounds served to permit the evaluation of the apparent molar enthalpies of solution.

  11. Influence of osmotic dehydration on ascorbic acid loss in pickled dry peppers (Capsicum chinense

    Directory of Open Access Journals (Sweden)

    Tissiane Mayara da Silva

    2012-10-01

    Full Text Available The objective of this work was (1 to develop a dehydrated pepper with 45% humidity, determining the drying curves for pepper, with and without osmotic pre-treatment and (2 to evaluate the influence of both drying and osmotic treatment on the content ascorbic acid (vitamin C in fresh pepper and pepper with 45% humidity. The experiments were carried out using the peppers cut in half, with and without osmotic pre-treatment, followed by drying in an oven at 70 ºC. The results showed that the osmotic pretreatment did not influence the retention of ascorbic acid during the drying of pepper. The sensory analysis regarding the color, flavor, and texture attributes revealed that there was no difference in the acceptability.

  12. Modulating effect of ascorbic Acid on transport-induced immunosuppression in goats.

    Science.gov (United States)

    Minka, Ndazo Salka; Ayo, Joseph Olusegun

    2011-01-01

    The effect of 12 h road transportation on some basic blood cells and the modulating role of ascorbic acid were investigated in 40 adult Red Sokoto goats during the hot dry season. The animals were divided into two groups, GI (experimental; n = 20) and GII (control; n = 20). Group 1 was administered with ascorbic acid (AA) per os at a dosage rate of 100 mg/kg body weight, while GII was given 10 mL of sterile water per goat. Forty minutes after the administration and loading, the goats were transported for 12 h. The result obtained in GII goats showed that loading, transportation, high ambient temperature (AT), and relative humidity (RH) encountered during transportation induced lymphopenia, neutrophilia, and eosinopenia, which can cause immunosuppression. In GI goats, the administration of AA prior to loading and transportation ameliorated the adverse effects of loading and transportation stress on neutrophil/lymphocyte ratio and eosinopenia of the goats.

  13. Kinetics of ascorbic acid loss during hot water blanching of fluted pumpkin (Telfairia occidentalis) leaves.

    Science.gov (United States)

    Ariahu, Charles C; Abashi, Diana K; Chinma, Chiemela Enyinnaya

    2011-08-01

    The kinetics of thermal degradation of ascorbic acid in fluted pumpkin leaves were investigated from 60 to 90°C (pH 5.0 to 6.5). Ascorbic acid degradation was modeled as a first order rate reaction with the rate constants increasing with increase in pH of the medium. The pH and temperature dependence of the rates of destruction gave highly significant correlations when analyzed by the thermal resistance and activated complex reaction rate methods. Activation energy (Ea) ranged from 41.2 to 18.2 kJ/mol while D-values ranged from 103.3 to 22.4 min. The changes in activation energy affected Ko values which ranged from 5.98 × 10(4) to 41.7 min(-1).

  14. Miniaturized ascorbic acid fuel cells with flexible electrodes made of graphene-coated carbon fiber cloth

    Science.gov (United States)

    Hoshi, Kazuki; Muramatsu, Kazuo; Sumi, Hisato; Nishioka, Yasushiro

    2016-04-01

    Ascorbic acid (AA) is a biologically friendly compound and exists in many products such as sports drinks, fruit, and even in human blood. Thus, a miniaturized and flexible ascorbic acid fuel cell (AAFC) is expected be a power source for portable or implantable electric devices. In this study, we fabricated an AAFC with anode and cathode dimensions of 3 × 10 mm2 made of a graphene-coated carbon fiber cloth (GCFC) and found that GCFC electrodes significantly improve the power generated by the AAFC. This is because the GCFC has more than two times the effective surface area of a conventional carbon fiber cloth and it can contain more enzymes. The power density of the AAFC in a phosphate buffer solution containing 100 mM AA at room temperature was 34.1 µW/cm2 at 0.46 V. Technical issues in applying the AAFC to portable devices are also discussed.

  15. Inducing dopaminergic differentiation of expanded rat mesencephalic neural stem cells by ascorbic acid in vitro

    Institute of Scientific and Technical Information of China (English)

    ZHENG Min; WANG Dongmei; HOU Lingling; LI Haimin; XIE Chao; JIAO Wencang; BAI Cixian; WANG Yaping; PEI Xuetao

    2004-01-01

    Ascorbic acid (AA) induced differentiation of neural stem cells (NSCs) into dopaminergic (DAergic) neurons is reported.NSCs derived from rat mesencephalon were maintained and expanded in a defined medium containing mitogens of basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF).Compared with the control, ascorbic acid treatment led to more DAergic neuronal differentiation as indicated by the expression of tyrosine hydroxylase (TH) and dopamine transporter (DAT), which are specific markers of dopamine neurons.AA induction also enhanced expression of Nurr1 and Shh.PD98059, an inhibitor of mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway, could block AA-induced Nurr1, TH and DAT mRNA expression.The results might suggest a new strategy to provide enough dopaminergic cells for the therapy of Parkinson's disease (PD), and Nurr1 and ERK signaling pathway might participate in the AA-induced DAergic differentiation.

  16. Efficacy of Ascorbic Acid on Reducing the Development of Contrast-Induced Nephropathy

    Directory of Open Access Journals (Sweden)

    Hojat Naghavi

    2016-11-01

    Full Text Available Introduction To assess the benefits of prophylactic ascorbic acid to reduce development of contrast-induced nephropathy (CIN in patients undergoing percutaneous coronary interventions (PCIs. Methods PubMed was searched with the search strategy of (vitamin C OR ascorbic acid AND (kidney OR renal AND (PCI OR percutaneous coronary Intervention OR cardiac OR heart. There was no date and language restriction for the selection of the articles. All the randomized controlled trials (RCTs which investigated the efficacy of AA on reducing the incidence of CIN were included. Totally 267 articles were found at the initial search; however, only 10 RCTs were eligible to be included. Odds ratio is presented for each of the articles as the effect size. Conclusions Controversial findings were reported on the efficacy of AA on reducing the CIN development; due to various limitations of these articles, there is still great debate among the cardiology and radiology communities, which increases the need for further researches.

  17. Effects of ascorbic acid supplementation in ileum myenteric neurons of streptozotocin-induced diabetic rats

    OpenAIRE

    SILVERIO, Sonia M.; Mari,Renata B.; Clebis,Naianne K.; SCOZ, Juliana R.; Germano,Ricardo de M.; Major,José A.A.; Pedro P. Bombonato; Sandra R. Stabille

    2009-01-01

    The exacerbation of the oxidative stress and of the polyol pathway which impair damage myenteric plexus are metabolic characteristics of diabetes. The ascorbic acid (AA) is an antioxidant and an aldose reductase inhibitor, which may act as neuroprotector. The effects of AA supplementation on the density and cellular body profile area (CP) of myenteric neurons in STZ-induced diabetes in rats were assessed. Four groups with five animals each were formed: normoglycemic (C); diabetic (D); AA-trea...

  18. Iron-rich drinking water and ascorbic acid supplementation improved hemolytic anemia in experimental Wistar rats.

    Science.gov (United States)

    Chaturvedi, Richa; Chattopadhyay, Pronobesh; Banerjee, Saumen; Bhattacharjee, Chira R; Raul, Prasanta; Borah, Kusum; Singh, Lokendra; Veer, Vijay

    2014-11-01

    Anemia is a frequent problem in both the primary and secondary health care programs. In contrast, most areas of northeast India are vulnerable to iron toxicity. In the present study, we documented the effect of administration of iron rich water on hemolytic anemia in a Wistar rats' animal model. Hemolytic anemia was induced by phenyl hydrazine through intraperitoneal route and diagnosed by the lowering of blood hemoglobin. After inducing the hemolytic anemia, 24 Wistar rats (n = 6 in four groups) were randomly assigned to 1 mg/l, 5 mg/l, and 10 mg/l ferric oxide iron along with 1 mg/ml ascorbic acid administered through drinking water; a control group was treated with iron-free water. The hematological and biochemical parameters, iron levels in liver, spleen, and kidney were estimated after 30 d of treatment. In the group treated with 5 mg/l iron and ascorbic acid, a significant increase of serum iron and ferritin, and a decrease of TIBC (total iron binding capacity) were observed without changes in other biochemical parameters and histopathological findings. However, in the group treated with 10 mg/l iron and ascorbic acid, hematological changes with significantly higher values for white blood cell count, serum glutamic phospho transaminase, serum glutamic oxaloacetic transaminase, alkaline phosphatase, glucose, splenic, and liver iron content, indicate potential toxicity at this supplementation level. Data suggest that the optimum concentration of iron (5 mg/l) and ascorbic acid solution may improve anemic conditions and may be therapeutically beneficial in the treatment of iron deficiency anemia without any negative impact, while 10 mg/l in drinking water seems to be the threshold for the initiation of toxicity.

  19. Application of super absorbent polymer and ascorbic acid to mitigate deleterious effects of cadmium in wheat

    OpenAIRE

    Moghadam,Hamid Reza Tohidi

    2016-01-01

    ABSTRACT The growing use of chemical fertilizers, insecticides and pesticides can cause potential contamination with heavy metals to soil and groundwater, posing environmental and health threats. Heavy metals can also affect crop yield. A greenhouse experiment was conducted to explore the role of ascorbic acid foliar application and soil-applied super absorbent to mitigate adverse effects of cadmium (Cd), in terms of biochemical parameters in wheat. The experiment was installed in a completel...

  20. Changes in Ascorbic Acid Content, Antioxidant Capacity and Sensory Quality of Fresh-cut Mangosteens During Storage

    Directory of Open Access Journals (Sweden)

    Supranee MANURAKCHINAKORN

    2004-06-01

    Full Text Available Fresh-cut mangosteens, stored in modified atmosphere packaging (MAP; 5% O2 + 9% CO2, in vacuum packaging (VAC and in air (AIR were examined for ascorbic acid content, antioxidant capacity and sensory quality during 14 days of storage at 4oC. After 4 days-storage, fresh-cut fruits with MAP resulted in better retention of ascorbic acid and antioxidant capacity than those stored in AIR throughout the storage. Furthermore, there were no significant differences in ascorbic acid contents between fruits stored in MAP and VAC, as well as antioxidant capacities, during the remaining period of storage. Fresh-cut fruits with MAP treatment obtained the highest sensory scores, compared with other treatments, throughout the entire period of storage. Fresh-cut mangosteens stored in MAP resulted in the best overall retention of ascorbic acid, antioxidant capacity and sensory quality.

  1. Attenuation of Renal Ischemia-Reperfusion (I/R) Injury by Ascorbic Acid in the Canine Nephrotomy

    National Research Council Canada - National Science Library

    Jong-Man Kim; Jae-Yeon Lee; Seong-Mok Jeong; Chang-Sik Park; Myung-Cheol Kim

    2010-01-01

    ...) injury and recovery of renal function in canine nephrotomy model. In the canine model, nine mixed dogs were subjected to renal nephrotomy with premedicated ascorbic acid and hepa-saline irrigation-aspiration (treatment group 2...

  2. Evaluation of non-thermal effects of electricity on ascorbic acid and carotenoid degradation in acerola pulp during ohmic heating.

    Science.gov (United States)

    Jaeschke, Débora Pez; Marczak, Ligia Damasceno Ferreira; Mercali, Giovana Domeneghini

    2016-05-15

    The effect of electric field on ascorbic acid and carotenoid degradation in acerola pulp during ohmic heating was evaluated. Ascorbic acid kinetic degradation was evaluated at 80, 85, 90 and 95°C during 60 min of thermal treatment by ohmic and conventional heating. Carotenoid degradation was evaluated at 90 and 95°C after 50 min of treatment. The different temperatures evaluated showed the same effect on degradation rates. To investigate the influence of oxygen concentration on the degradation process, ohmic heating was also carried out under rich and poor oxygen modified atmospheres at 90°C. Ascorbic acid and carotenoid degradation was higher under a rich oxygen atmosphere, indicating that oxygen is the limiting reagent of the degradation reaction. Ascorbic acid and carotenoid degradation was similar for both heating technologies, demonstrating that the presence of the oscillating electric field did not influence the mechanisms and rates of reactions associated with the degradation process.

  3. Enzyme-catalyzed Transesterification of Unusual Substrate: Synthesis of Acyclovir and L-ascorbic Acid (Vitamin C) Vinyl Esters

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The synthesis of acyclovir and L-ascorbic acid with divinyladipate was performed with alkaline protease from Bacillus subtilis and lipase from Lipozyme (immobilized from Mucor miehei) in different anhydrous organic solvents. Two corresponding derivatives were obtained.

  4. Cytoprotective effects of amifostine, ascorbic acid and N-acetylcysteine against methotrexate-induced hepatotoxicity in rats

    OpenAIRE

    Akbulut, Sami; Elbe, Hulya; Eris, Cengiz; Dogan, Zumrut; Toprak, Gulten; Otan, Emrah; Erdemli, Erman; Turkoz, Yusuf

    2014-01-01

    AIM: To investigate the potential role of oxidative stress and the possible therapeutic effects of N-acetyl cysteine (NAC), amifostine (AMF) and ascorbic acid (ASC) in methotrexate (MTX)-induced hepatotoxicity.

  5. Ascorbic acid decomposition into oxalate ions: a simple synthetic route towards oxalato-bridged heterometallic 3d-4f clusters.

    Science.gov (United States)

    Dinca, Alina S; Shova, Sergiu; Ion, Adrian E; Maxim, Catalin; Lloret, Francesc; Julve, Miguel; Andruh, Marius

    2015-04-28

    Two types of oxalato-bridged heterometallic 3d-4f dodeca- and hexanuclear compounds have been obtained by connecting six bi- and, respectively, trinuclear moieties through oxalato bridges arising from the slow decomposition of the L-ascorbic acid.

  6. Novel graphene flowers modified carbon fibers for simultaneous determination of ascorbic acid, dopamine and uric acid.

    Science.gov (United States)

    Du, Jiao; Yue, Ruirui; Ren, Fangfang; Yao, Zhangquan; Jiang, Fengxing; Yang, Ping; Du, Yukou

    2014-03-15

    A novel and sensitive carbon fiber electrode (CFE) modified by graphene flowers was prepared and used to simultaneously determine ascorbic acid (AA), dopamine (DA) and uric acid (UA). SEM images showed that beautiful and layer-petal graphene flowers homogeneously bloomed on the surface of CFE. Moreover, sharp and obvious oxidation peaks were found at the obtained electrode when compared with CFE and glassy carbon electrode (GCE) for the oxidation of AA, DA and UA. Also, the linear calibration plots for AA, DA and UA were observed, respectively, in the ranges of 45.4-1489.23 μM, 0.7-45.21 μM and 3.78-183.87 μM in the individual detection of each component. By simultaneously changing the concentrations of AA, DA and UA, their oxidation peaks appeared at -0.05 V, 0.16 V and 2.6 V, and the good linear responses ranges were 73.52-2305.53 μM, 1.36-125.69 μM and 3.98-371.49 μM, respectively. In addition, the obtained electrode showed satisfactory results when applied to the determination of AA, DA and UA in urine and serum samples.

  7. application of ascorbic acid 2-phosphate as a new voltammetric ...

    African Journals Online (AJOL)

    a

    acid 2-phosphate (AAP) as a new voltammetric substrate has been ... further applied to determine the ALP content in healthy human serum and the results were in ... substrates to produce phenol or p-aminophenol, which is electroactive and can be ... bovine serum, human serum and untreated human blood with the linear ...

  8. Delphinidin immobilized on silver nanoparticles for the simultaneous determination of ascorbic acid, noradrenalin, uric acid, and tryptophan

    Directory of Open Access Journals (Sweden)

    Navid Nasirizadeh

    2016-04-01

    Full Text Available In the present study, the fabrication of a new modified electrode for electrocatalytic oxidation of noradrenalin, based on the delphinidin immobilized on silver nanoparticles modified glassy carbon electrode. Cyclic voltammetry was used to investigate the redox properties of this modified electrode. The surface charge transfer rate constant (ks and the charge transfer coefficient (α for the electron transfer between the glassy carbon electrode and the immobilized delphinidin were calculated. The differential pulse voltammetry exhibited two linear dynamic ranges and a detection limit of 0.40μM for noradrenalin determination. Moreover, the present electrode could separate the oxidation peak potentials of ascorbic acid, noradrenalin, uric acid, and tryptophan in a mixture. The usefulness of this nanosensor was also investigated for the determination of ascorbic acid, noradrenalin, and uric acid in pharmaceutical and biological fluid samples with satisfactory results.

  9. Facile synthesis of graphene from graphite using ascorbic acid as reducing agent

    Science.gov (United States)

    Andrijanto, Eko; Shoelarta, Shoerya; Subiyanto, Gatot; Rifki, Sadur

    2016-04-01

    Graphene has attracted a tremendous attention in recent years due to its unique properties such as mechanical, thermal, optical and electrical properties. However, a large scale production of this material is still an issue and subjected to intense research efforts. Here, we show a simple and green approach of the graphene synthesis from graphene oxide using ascorbic acid as reduction agent. A facile synthesis of graphene (rGO) through chemical oxidation of graphite into graphene oxide (GO) was described using modified Hummers method (Improved Tour Method/ITM). The ITM method does not produce toxic gas and the temperature of the oxidation is easily controlled using ice bath. The synthesized of graphene oxide was highly soluble and stable in water. The reduction of graphene oxide into graphene was performed using ascorbic acid (AA) in mild condition. The combined ITM method and green reduction using ascorbic acid open the avenue of replacing hydrazine in the reduction of graphite oxide into graphene and may be very important step for bulk production of graphene.

  10. Effect of the Electric Field Frequency on Ascorbic Acid Degradation during Thermal Treatment by Ohmic Heating

    Science.gov (United States)

    Mercali, Giovana Domeneghini; Schwartz, Steven; Marczak, Ligia Damasceno Ferreira; Tessaro, Isabel Cristina; Sastry, Sudhir

    2014-01-01

    In this work, the influence of the electric field frequency and solids content on the degradation kinetics of ascorbic acid during ohmic heating of acerola pulp and acerola serum was investigated. The degradation percentage of ascorbic acid in the pulp after 120 min of heating varied between 12 and 17%. For the serum, the degradation percentage was in the range of 13 and 18%. The results were fitted to the first-order model, and the kinetic rate constants ranged from 1.1 to 1.6 × 10−3 min−1 and from 1.1 to 1.5 × 10−3 min−1 for pulp and serum, respectively. D values ranged between 1480 and 2145 min for the pulp and between 1524 and 1951 min for the serum. A distinct behavior between the kinetic parameters of the pulp and serum in electric field frequencies ranging from 10 to 1000 Hz indicates that the presence of distinct amounts and types of solids might affect the rate of the electron transfer in electrochemical reactions. These variables may also affect the polarization process stimulated by the oscillating electric field. The non-achievement of the equilibrium of the polarization process may have an influence on oxidation reactions, affecting the predisposition to hydrogen donation from the ascorbic acid molecule. PMID:24892902

  11. Attenuation of ischemic preconditioning in pigs by scavenging of free oxyradicals with ascorbic acid.

    Science.gov (United States)

    Skyschally, Andreas; Schulz, Rainer; Gres, Petra; Korth, Hans-Gert; Heusch, Gerd

    2003-02-01

    Free oxyradicals are involved in the signal transduction of ischemic preconditioning in rats and rabbits. Data from larger mammals in which the infarct development is closer to that in humans are lacking. We have therefore investigated the impact of the radical scavenger ascorbic acid on ischemic preconditioning in pigs. In 33 anesthetized pigs, the left anterior descending coronary artery was perfused from an extracorporeal circuit. Infarct size (measured as percent area at risk) was determined by triphenyltetrazolium chloride staining. In placebo-treated animals undergoing 90 min of severe ischemia and 120 min of reperfusion, infarct size averaged 26.9 +/- 3.9% (mean +/- SE; n = 9). Ischemic preconditioning by 10 min of ischemia and 15 min of reperfusion reduced infarct size to 6.4 +/- 2.4% (P < 0.05 vs. placebo; n = 9). Intravenous infusion of ascorbic acid (30 min before ischemic preconditioning or ischemia; 2-g bolus followed by 25 mg/min until the end of ischemia) had no effect on infarct size per se (22.6 +/- 6.5%; n = 6), but largely abolished the infarct size reduction by ischemic preconditioning (19.1 +/- 5.4%; n = 9). Scavenging of free oxyradicals with ascorbic acid largely attenuates the beneficial effect of ischemic preconditioning in pigs.

  12. Low ascorbic acid and increased oxidative stress in gulo(-/-) mice during development.

    Science.gov (United States)

    Harrison, Fiona E; Meredith, M Elizabeth; Dawes, Sean M; Saskowski, Jeanette L; May, James M

    2010-08-19

    Vitamin C (ascorbic acid, AA) depletion during prenatal and postnatal development can lead to oxidative stress in the developing brain and other organs. Such damage may lead to irreversible effects on later brain function. We studied the relationship between AA deficiency and oxidative stress during development in gulonolactone oxidase (gulo) knockout mice that are unable to synthesize their own ascorbic acid. Heterozygous gulo(+/-) mice can synthesize AA and typically have similar tissue levels to wild-type mice. Gulo(+/-) dams were mated with gulo(+/-) males to provide offspring of each possible genotype. Overall, embryonic day 20 (E20) and postnatal day 1 (P1) pups were protected against oxidative stress by sufficient AA transfer during pregnancy. On postnatal day 10 (P10) AA levels were dramatically lower in liver and cerebellum in gulo(-/-) mice and malondialdehyde (MDA) levels were significantly increased. In postnatal day 18 pups (P18) AA levels decreased further in gulo(-/-) mice and oxidative stress was observed in the accompanying elevations in MDA in liver, and F(2)-isoprostanes in cortex. Further, total glutathione levels were higher in gulo(-/-) mice in cortex, cerebellum and liver, indicating that a compensatory antioxidant system was activated. These data show a direct relationship between AA level and oxidative stress in the gulo(-/-) mice. They reinforce the critical role of ascorbic acid in preventing oxidative stress in the developing brain in animals that, like humans, cannot synthesize their own AA.

  13. Decylglucoside-based microemulsions for cutaneous localization of lycopene and ascorbic acid.

    Science.gov (United States)

    Pepe, Dominique; Phelps, Jessica; Lewis, Kevin; Dujack, Jared; Scarlett, Katrina; Jahan, Sumaya; Bonnier, Emilee; Milic-Pasetto, Tatjana; Hass, Martha A; Lopes, Luciana B

    2012-09-15

    Cutaneous delivery of combinations of antioxidants offers the possibility of enhanced protection against UV-radiation. In this study, we investigated the potential of sugar-based microemulsions containing monoglycerides to promote simultaneous cutaneous delivery of lycopene and ascorbic acid, and increase tissue antioxidant activity. Lycopene and ascorbic acid were incorporated (0.04% and 0.2% (w/w), respectively) in decylglucoside-based microemulsions containing isopropyl myristate mixed with monocaprylin (ME-MC), monolaurin (ME-ML) or monoolein (ME-MO) as oil phase. The microemulsions increased lycopene delivery into porcine ear skin by 3.3- to 8-fold compared to a drug solution. The effect of microemulsions on ascorbic acid cutaneous delivery was more modest (1.5-3-fold), and associated with an approximately 2-fold increase in transdermal delivery. According to their penetration-enhancing ability, the microemulsions were ranked ME-MC>ME-MO>ME-ML. This superiority of ME-MC coincided with a stronger effect in decreasing skin electrical resistance. After 18 h of treatment, the viability of bioengineered skin treated with ME-MC was 2.2-times higher compared to Triton-X100 (moderate irritant), demonstrating that ME-MC is less cytotoxic. Skin treatment with ME-MC containing both antioxidants increased the tissue antioxidant activity by 10.2-fold, but no synergism between the antioxidants was observed.

  14. Effect of the electric field frequency on ascorbic acid degradation during thermal treatment by ohmic heating.

    Science.gov (United States)

    Mercali, Giovana Domeneghini; Schwartz, Steven; Marczak, Ligia Damasceno Ferreira; Tessaro, Isabel Cristina; Sastry, Sudhir

    2014-06-25

    In this work, the influence of the electric field frequency and solids content on the degradation kinetics of ascorbic acid during ohmic heating of acerola pulp and acerola serum was investigated. The degradation percentage of ascorbic acid in the pulp after 120 min of heating varied between 12 and 17%. For the serum, the degradation percentage was in the range of 13 and 18%. The results were fitted to the first-order model, and the kinetic rate constants ranged from 1.1 to 1.6×10(-3) min(-1) and from 1.1 to 1.5×10(-3) min(-1) for pulp and serum, respectively. D values ranged between 1480 and 2145 min for the pulp and between 1524 and 1951 min for the serum. A distinct behavior between the kinetic parameters of the pulp and serum in electric field frequencies ranging from 10 to 1000 Hz indicates that the presence of distinct amounts and types of solids might affect the rate of the electron transfer in electrochemical reactions. These variables may also affect the polarization process stimulated by the oscillating electric field. The non-achievement of the equilibrium of the polarization process may have an influence on oxidation reactions, affecting the predisposition to hydrogen donation from the ascorbic acid molecule.

  15. Seasonal profiles of leaf ascorbic acid content and redox state in ozone-sensitive wildflowers

    Energy Technology Data Exchange (ETDEWEB)

    Burkey, Kent O. [Plant Science Research Unit, USDA-ARS and North Carolina State University, 3127 Ligon Street, Raleigh, NC 27607 (United States)]. E-mail: koburkey@unity.ncsu.edu; Neufeld, Howard S. [Appalachian State University, Boone, NC (United States); Souza, Lara [Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN (United States); Chappelka, Arthur H. [Auburn University, Auburn, AL (United States); Davison, Alan W. [University of Newcastle, Newcastle, England (United Kingdom)

    2006-10-15

    Cutleaf coneflower (Rudbeckia laciniata L.), crown-beard (Verbesina occidentalis Walt.), and tall milkweed (Asclepias exaltata L.) are wildflower species native to Great Smoky Mountains National Park (U.S.A.). Natural populations of each species were analyzed for leaf ascorbic acid (AA) and dehydroascorbic acid (DHA) to assess the role of ascorbate in protecting the plants from ozone stress. Tall milkweed contained greater quantities of AA (7-10 {mu}mol g{sup -1} fresh weight) than crown-beard (2-4 {mu}mol g{sup -1} fresh weight) or cutleaf coneflower (0.5-2 {mu}mol g{sup -1} fresh weight). DHA was elevated in crown-beard and cutleaf coneflower relative to tall milkweed suggesting a diminished capacity for converting DHA into AA. Tall milkweed accumulated AA in the leaf apoplast (30-100 nmol g{sup -1} fresh weight) with individuals expressing ozone foliar injury symptoms late in the season having less apoplast AA. In contrast, AA was not present in the leaf apoplast of either crown-beard or cutleaf coneflower. Unidentified antioxidant compounds were present in the leaf apoplast of all three species. Overall, distinct differences in antioxidant metabolism were found in the wildflower species that corresponded with differences in ozone sensitivity. - Wildflower species exhibit differences in ascorbic acid content and redox status that affect ozone sensitivity.

  16. Extracellular ascorbic acid fluctuation during the protective process of ischemic preconditioning in rabbit renal ischemia-reperfusion model measured

    Institute of Scientific and Technical Information of China (English)

    LIU Lei; LIN Yu-qing; YAN Long-tao; HONG Kai; HOU Xiao-fei; MAO Lan-qun; MA Lu-lin

    2010-01-01

    Background Ascorbic acid has important antioxidant properties, and may play a role in the protective effects of ischemic preconditioning on later ischemia-reperfusion. Herein, we examined the role of endogenous extracellular ascorbic acid in ischemic preconditioning in the kidney.Methods We developed a solitary rabbit kidney model where animals received ischemia-reperfusion only (ischemia-reperfusion group, n=15) or ischemic preconditioning followed by ischemia-reperfusion (ischemic preconditioning group, n=15). Ischemia-reperfusion was induced by occluding and loosening of the renal pedicle. The process of ischemic preconditioning included 15-minute brief ischemia and 10-minute reperfusion. In vivo microdialysis coupled with online electrochemical detection was used to determine levels of endogenous extracellular ascorbic acid in both groups. The extent of tissue damage was determined in kidney sections stained with hematoxylin and eosin. Serum creatinine and urea nitrogen were also detected to assess renal function.Results During ischemia-reperfusion, the extracellular ascorbic acid concentration during ischemia increased rapidly to the peak level ((130.01 ±9.98)%), and then decreased slowly to near basal levels. Similar changes were observed during reperfusion (peak level, (126.78±18.24)%). In the ischemic preconditioning group there was a similar pattern of extracellular ascorbic acid concentration during ischemic preconditioning. However, the ascorbic acid level was significantly lower during the ischemia and early reperfusion stage compared to the ischemia-reperfusion group. Additionally, the extent of glomerular ischemic collapse, tubular dilation, tubular denudation, and loss of brush border were markedly attenuated in the ischemic preconditioning group. Levels of serum creatinine and urea nitrogen were also decreased significantly in the ischemic preconditioning group.Conclusions Ischemic preconditioning may protect renal tissue against ischemia

  17. L-Ascorbic acid can abrogate SVCT-2-dependent cetuximab resistance mediated by mutant KRAS in human colon cancer cells.

    Science.gov (United States)

    Jung, Soo-A; Lee, Dae-Hee; Moon, Jai-Hee; Hong, Seung-Woo; Shin, Jae-Sik; Hwang, Ih Yeon; Shin, Yu Jin; Kim, Jeong Hee; Gong, Eun-Yeung; Kim, Seung-Mi; Lee, Eun Young; Lee, Seul; Kim, Jeong Eun; Kim, Kyu-Pyo; Hong, Yong Sang; Lee, Jung Shin; Jin, Dong-Hoon; Kim, TaeWon; Lee, Wang Jae

    2016-06-01

    Colon cancer patients with mutant KRAS are resistant to cetuximab, an antibody directed against the epidermal growth factor receptor, which is an effective clinical therapy for patients with wild-type KRAS. Numerous combinatorial therapies have been tested to overcome the resistance to cetuximab. However, no combinations have been found that can be used as effective therapeutic strategies. In this study, we demonstrate that L-ascorbic acid partners with cetuximab to induce killing effects, which are influenced by sodium-dependent vitamin C transporter 2 (SVCT-2) in human colon cancer cells with a mutant KRAS. L-Ascorbic acid treatment of human colon cancer cells that express a mutant KRAS differentially and synergistically induced cell death with cetuximab in a SVCT-2-dependent manner. The ectopic expression of SVCT-2 induced sensitivity to L-ascorbic acid treatment in human colon cancer cells that do not express SVCT-2, whereas the knockdown of endogenous SVCT-2 induced resistance to L-ascorbic acid treatment in SVCT-2-positive cells. Moreover, tumor regression via the administration of L-ascorbic acid and cetuximab in mice bearing tumor cell xenografts corresponded to SVCT-2 protein levels. Interestingly, cell death induced by the combination of L-ascorbic acid and cetuximab resulted in both apoptotic and necrotic cell death. These cell death mechanisms were related to a disruption of the ERK pathway and were represented by the impaired activation of RAFs and the activation of the ASK-1-p38 pathway. Taken together, these results suggest that resistance to cetuximab in human colon cancer patients with a mutant KRAS can be bypassed by L-ascorbic acid in an SVCT-2-dependent manner. Furthermore, SVCT-2 in mutant KRAS colon cancer may act as a potent marker for potentiating L-ascorbic acid co-treatment with cetuximab.

  18. Potential Application of Ascorbic Acid, Citric Acid and Oxalic Acid for Browning Inhibition in Fresh-Cut Fruits and Vegetables

    Directory of Open Access Journals (Sweden)

    Weerayuth SUTTIRAK

    2010-01-01

    Full Text Available The market for fresh-cut fruits and vegetables has grown rapidly in recent decades as a result of their freshness, convenience, and human health benefits. However, fresh fruits and vegetables deteriorate very rapidly after processing, especially cut-surface browning resulting from wound-induced physiological and biochemical changes. The application of antibrowning agents is one of the most effective methods for controlling the enzymatic browning reaction in fresh-cut fruits and vegetables. This article reviews the use of nature identical antibrowning agents, which are generally recognized as safe (GRAS including ascorbic acid, citric acid and oxalic acid for preventing browning in fresh-cut fruits and vegetables. Factors affecting inhibitory efficiency of the antibrowning agents and synergistic effects of the mixtures in various fresh-cut fruits and vegetables are presented.

  19. Chlorambucil and ascorbic acid-mediated anticancer activity and hematological toxicity in Dalton's ascites lymphoma-bearing mice.

    Science.gov (United States)

    Kalita, Suravi; Verma, Akalesh Kumar; Prasad, Surya Bali

    2014-02-01

    Chlorambucil is an anticancer drug with alkylating and immunosuppressive activities. Considering various reports on the possible antioxidant/protective functions of ascorbic acid (vitamin C), it was aimed at to explore the modulatory effect of ascorbic acid on therapeutic efficacy and toxicity induced by chlorambucil. Dalton's ascites lymphoma tumor serially maintained in Swiss albino mice were used for the present experiments. The result of antitumor activity showed that combination treatment with ascorbic acid and chlorambucil exhibited enhanced antitumor activity with 170% increase in life span (ILS), which is significantly higher as compared to chlorambucil alone (ILS 140%). Analysis of apoptosis in Dalton's lymphoma tumor cells revealed a significantly higher apoptotic index after combination treatment as compared to chlorambucil alone. Blood hemoglobin content, erythrocytes and leukocytes counts were decreased after chlorambucil treatment, however, overall recovery in these hematological values was noted after combination treatment. Chlorambucil treatment also caused morphological abnormalities in red blood cells, majority of which include acanthocytes, burr and microcystis. Combination treatment of mice with ascorbic acid plus chlorambucil showed less histopathological changes in kidney as compared to chlorambucil treatment alone, thus, ascorbic acid is effective in reducing chlorambucil-induced renal toxicity in the hosts. Based on the results, for further development, hopefully into the clinical usage, the administration of ascorbic acid in combination with chlorambucil may be recommended.

  20. Influence of antioxidant (L- ascorbic acid on tolbutamide induced hypoglycaemia/antihyperglycaemia in normal and diabetic rats

    Directory of Open Access Journals (Sweden)

    Vardhan Vishnu A

    2005-03-01

    Full Text Available Abstract Background Diabetes mellitus is a chronic metabolic disorder characterized by hyperglycaemia. Increased oxidative stress and decreased antioxidant levels are the leading cause of diabetes and diabetic complications. So it is felt that supplementation of antioxidants may be useful in controlling the glucose levels and to postpone the occurrence of diabetic complications. The objective of our study is to find the influence of antioxidant supplementation (L-ascorbic acid on tolbutamide activity in normal and diabetic rats. Methods L- ascorbic acid/tolbutamide/L-ascorbic acid + tolbutamide were administered orally to 3 different groups of albino rats of either sex in normal and diabetic condition. Blood samples were collected from retro-orbital puncture at different time intervals and were analyzed for blood glucose by GOD-POD method. Diabetes was induced by alloxan 100 mg/kg body weight administered by I.P route. Results L-ascorbic acid/ tolbutamide produced hypoglycaemic activity in a dose dependant manner in normal and diabetic condition. In the presence of L-ascorbic acid, tolbuatmide produced early onset of action and maintained for longer period compared to tolbutamide matching control. Conclusion Supplementation of antioxidants like L-ascorbic acid was found to improve tolbutamide response in normal and diabetic rats.

  1. Effects of ascorbic acid and sugars on solubility, thermal, and mechanical properties of egg white protein gels.

    Science.gov (United States)

    Mohammadi Nafchi, Abdorreza; Tabatabaei, Ramin H; Pashania, Bita; Rajabi, Hadiseh Z; Karim, A A

    2013-11-01

    The effects of reducing sugars (fructose, glucose, ribose, and arabinose), sucrose, and ascorbic acid were studied on thermo-mechanical properties and crosslinking of egg white proteins (EWP) through Maillard reaction. Sugars (0%, 1%, 5%, and 10%) and ascorbic acid (0%, 0.25%, 0.5%, and 2.5%) were added to EWP solutions. Thermal denaturation and crosslinking of EWP were characterized by differential scanning calorimetry (DSC). Mechanical properties (failure strength, failure strain and Young's modulus) of modified and unmodified EWP gels were evaluated by texture analyzer. Ascorbic acid decreased thermal denaturation temperature of EWP, but the reducing sugars increased the denaturation temperature. DSC thermograms of EWP showed that ascorbic acid exhibited an exothermic transition (≈110 °C) which was attributed to Maillard crosslinking of the protein. The reduction in pH (from 7.21 to ≈6) and protein solubility of egg white protein gel (from ≈70% to ≈10%) provides further evidence of the formation of Maillard cross-linking. Reactive sugars (ribose and arabinose) increased the mechanical properties of EWP gels, whereas ascorbic acid decreased the mechanical properties. Generally, the effect of ascorbic acid was more pronounced than that of various reducing sugars on the thermal and mechanical properties of egg white proteins.

  2. Gallic acid as a protective antioxidant against anthocyanin degradation and color loss in vitamin-C fortified cranberry juice.

    Science.gov (United States)

    Roidoung, Sunisa; Dolan, Kirk D; Siddiq, Muhammad

    2016-11-01

    The objective of this study was to evaluate different antioxidants for anthocyanin (ACY) retention in vitamin C fortified cranberry juice and assess its quality. Cranberry juice was fortified with 40-80mg/100mL vitamin C and added hesperidin, catechin, and gallic acid at different concentrations. Juice was pasteurized at 85°C for 1min and stored at 23°C for 16days. ACYs, vitamin C, color intensity, and browning index (BI) were evaluated at 2-day intervals. Gallic acid was found to be the most effective antioxidant against ACYs degradation and significantly (pgallic acid-added juice was significantly lower (0.80 vs 1.00) than the control juice. The outcome of this research provided a potential solution of using gallic acid to preserve a health-beneficial component (ACYs), and endogenous red color in cranberry juice.

  3. Efficacy of phytic acid as an inhibitor of enzymatic and non-enzymatic browning in apple juice.

    Science.gov (United States)

    Du, Yunjian; Dou, Siqi; Wu, Shengjun

    2012-11-15

    Browning decreases the commercial value of apple juice, and therefore colour preservation during processing and storage is the main objective of manufacturers. In this study, the efficacy of phytic acid as a browning inhibitor for use on apple juice was investigated. Browning of apple juice treated with phytic acid was monitored during processing and storage. 0.1 mM Phytic acid inhibited the polyphenol oxidase (PPO) from the apple juice by 99.2%. Consequently, the apple juice treated with phytic acid had significantly lower browning formation during processing and after 6 months of storage at room temperature compared with the control (p<0.05). Results indicate that this is a promising way to inhibit browning in apple juice.

  4. Ascorbic acid levels of aqueous humor of dogs after experimental phacoemulsification.

    Science.gov (United States)

    De Biaggi, Christianni P; Barros, Paulo S M; Silva, Vanessa V; Brooks, Dennis E; Barros, Silvia B M

    2006-01-01

    Phacoemulsification has been successfully employed in humans and animals for lens extraction. This ultrasonic extracapsular surgical technique induces hydroxyl radical formation in the anterior chamber, which accumulates despite irrigation and aspiration. In this paper we determined the total antioxidant status of aqueous humor after phacoemulsification by measuring aqueous humor ascorbic acid levels. Mixed-breed dogs (n = 11; weighing about 10 kg) with normal eyes as determined by slit-lamp biomicroscopy, applanation tonometry, and indirect ophthalmoscopy had phacoemulsification performed in one eye with the other eye used as a control. Samples of aqueous humor were obtained by anterior chamber paracentesis before surgery and at days 1, 2, 3, 7, and 15 after surgery. Total aqueous humor antioxidant status was inferred from the capacity of aqueous humor to inhibit free radical generation by 2,2-azobis (2-amidopropane) chlorine. Ascorbic acid concentrations were measured by high-pressure liquid chromatography with UV detection. Protein content was determined with the biuret reagent. Statistical analysis was performed by anova followed by the paired t-test. Total antioxidant capacity was reduced from 48 to 27 min during the first 24 h with a gradual increase thereafter, remaining statistically lower than the control eye until 7 days postoperatively. Reduced levels of ascorbic acid followed this reduction in antioxidant capacity (from 211 to 99 microm after 24 h), remaining lower than the control eye until 15 days postoperatively. Protein concentration in aqueous humor increased from 0.62 mg/mL to 30.8 mg/mL 24 h after surgery, remaining statistically lower than the control eye until 15 days postoperatively. Paracentesis alone did not significantly alter the parameters measured. These results indicate that after phacoemulsification, the aqueous humor ascorbic acid levels and antioxidant defenses in aqueous humor are reduced, indirectly corroborating free radical

  5. Lactic acid fermentation in vegetable juices supplemented with different content of brewer’s yeast autolysate

    Directory of Open Access Journals (Sweden)

    Rakin Marica B.

    2005-01-01

    Full Text Available The work is concerned with the conditions for lactic acid fermentation in a mixture of beetroot (Beta vulgaris L juice and carrot (Daucus carota L juice and different content of brewer’s yeast autolysate with Lactobacillus plantarum A112 and with Lactobacillus acidophilus NCDO 1748.Both cultures showed good biochemical activity in these mixtures. The production of lactic acid has been stimulated using the higher content of brewer’s yeast autolysate. In these mixtures, L. plantarum A112 has shown better growth and lactic acid production than L. acidophilus NCDO 1748.

  6. Effect of activated charcoal on patulin, fumaric acid and some other properties of apple juice.

    Science.gov (United States)

    Kadakal, C; Nas, S

    2002-02-01

    In this study, 0, 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 g/l amounts of activated charcoal (AC) were added into apple juice with a patulin content of 62.3 ppb obtained from a well-established manufacturing company. Apple juice samples were then mixed for 0, 5, 10, 20, and 30 min, respectively. Considerable reduction in the patulin and HMF values was found while there is a dramatic improvement in the colour and clearness of apple juice. However, AC did not cause a significant decrease in the fumaric acid level of apple juice. The best result was obtained at 3.0 g/l AC mixed for 5 min. In addition, a negligible reduction in brix and pH values of samples was observed.

  7. Phenolic compounds in juice of “Isabel” grape treated with abscisic acid for color improvement

    Directory of Open Access Journals (Sweden)

    Yamamoto Lilian Yukari

    2015-01-01

    Full Text Available Isabel grape is the main cultivar used to produce juice in Brazil, which has rusticity and high productivity, but it is deficient in anthocyanins, a pigment responsible for the color. Thus, an alternative is the application of abscisic acid (S-ABA, which is responsible to promote the synthesis of anthocyanins. The aim of this work was to evaluate the phenolic compounds composition in “Isabel” grape juice treated with S-ABA, by HPLC-DAD–ESI-MS/MS technique. The results showed the increasing in total anthocyanin concentration in juices, with S-ABA treatments, as well as the proportion of B-ring tri-substituted anthocyanidins. Regarding total flavonols, differences were only significant in juices obtained in 2012 season. S-ABA treatments did not significantly affect the hydroxycinnamic acid derivatives, flavan-3-ols, resveratrol and antioxidant capacity of juices. Juice from “Isabel” grapes treated with S-ABA provides an enhancement of total anthocyanin concentration, mainly when grapes are treated before or at the onset of véraison.

  8. Lactic acid production from date juice using lactobacillus casei ATCC 393 in batch fermentation

    Directory of Open Access Journals (Sweden)

    Kaavessina Mujtahid

    2017-01-01

    Full Text Available Lactobacillus casei ATCC 393 was employed as a fermentative organism to convert sugars from date juice into lactic acid. Both glucose and fructose in date juice were fermented directly without any pretreatment. The influences of supplementation of yeast extract and date juice concentration on some fermentation parameters, such as: cell growth rate, sugar conversion, productivity and yield, were investigated using this bacterium in batch fermentation. The results showed that by adding yeast extract about 20g/l in a date juice medium, the maximum specific growth rate of bacteria (μm enhanced from 0.1229 to 0.1819 g/l. Meanwhile, increasing date juice concentration from 86.6942 to 158.9181 and 229.5367 g/l enhanced the μm from 0.1819 to 0.2107 and 0.1916 g/l, respectively. It indicated that the optimum value for μm is 0.2107 g/l in this concentration range. In the date juice concentration of 158.9181 g/l, the optimum lactic acid can be produced is 117.8301 g/l with yield of 92.685% for 48 h.

  9. Analysis of organic acids in fruit juices by liquid chromatography-mass spectrometry: an enhanced tool for authenticity testing.

    Science.gov (United States)

    Ehling, Stefan; Cole, Shannon

    2011-03-23

    Organic acid analysis plays a fundamental role in the testing of authenticity of fruit juices. Analytical methods used routinely for organic acids suffer from poor reproducibility, often give false positives/negatives for tartaric acid, and do not offer the possibility of analyte confirmation. There are conflicting reports in the literature on the presence/absence of tartaric acid in pomegranate juice, a potential indicator of adulteration with grape juice. In this work, a method based on stable isotope dilution liquid chromatography-tandem mass spectrometry is described for citric, malic, quinic, and tartaric acid in fruit juices. Validation data including precision and recovery in six types of juice are presented. Tartaric and quinic acids were confirmed in pomegranate juice at concentrations of 1-5 and ∼1 mg/L, respectively. These concentrations are much lower than those resulting from adulteration with grape juice and apple juice, respectively, at the 5% level. A separate method for isocitric acid in orange juice based on the single standard addition method is also described.

  10. Effect of L (+) ascorbic acid and monosodium glutamate concentration on the morphology of calcium carbonate

    Science.gov (United States)

    Saraya, Mohamed El-shahte Ismaiel

    2015-11-01

    In this study, monosodium glutamate and ascorbic acid were used as crystal and growth modifiers to control the crystallization of CaCO3. Calcium carbonate prepared by reacting a mixed solution of Na2CO3 with CaCl2 at ambient temperature, (25 °C), constant Ca++/ CO3- - molar ratio and pH with stirring. The polymorph and morphology of the crystals were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The results indicate that rhombohedral calcite was only formed in water without organic additives, and both calcite and spherical vaterite with various morphologies were produced in the presence of monosodium glutamate. The content of vaterite increased as the monosodium glutamate increased. In addition, spherical vaterite was obtained in the presence of different concentrations of ascorbic acid. The spherical vaterite posses an aggregate shape composed of nano-particles, ranging from 30 to 50 nm as demonstrated by the SEM and TEM analyses. Therefore, the ascorbic stabilizes vaterite and result in nano-particles compared to monosodium glutamate.

  11. Ascorbic acid: new role of an age-old micronutrient in the management of periodontal disease in older adults.

    Science.gov (United States)

    Alagl, Adel S; Bhat, Subraya Giliyar

    2015-03-01

    To review the new role of an age-old micronutrient - ascorbic acid - in the management of periodontal disease. Articles pertaining to the topic were searched in PubMed and other search engines from year 1974 to April 2014 with the following key words: "ascorbic acid," "ascorbate," "vitamin C," "periodontal disease," "gingivitis," "periodontitis," "anti-oxidants" and "elderly." Balanced nutrition is an essential factor in the elderly. Modification of nutritional requirement is important to overcome the effect of an unbalanced diet in older individuals as a result of several external and internal host-associated factors. Micronutrient requirements as aging advances could change, and require due attention. Ascorbic acid and its relationship with periodontal disease are very well known. However, recent changes in the concept of understanding the pathogenicity has led to a new path of therapeutic intervention with ascorbic acid in many chronic diseases. Oxidative stress with its associated burden might alter the disease process. In the era of "periodontal medicine," the impact of remote tissue changes on systemic disease has to be taken into serious consideration. Deficiency of nutritional impact on the host, with micronutrient vitamin C detailed in this review with sources, absorption, interaction and its relationship with systemic disease, and thereby the impact on periodontal disease. Ascorbic acid plays an important role in the aging process, and in the maintenance of periodontal health in the elderly. © 2014 Japan Geriatrics Society.

  12. Cranberry juice and combinations of its organic acids are effective against experimental urinary tract infection

    DEFF Research Database (Denmark)

    Jensen, Heidi Dorthe; Struve, Carsten; Christensen, Søren Brøgger

    2017-01-01

    The antibacterial effect of cranberry juice and the organic acids therein on infection by uro28 pathogenic Escherichia coli was studied in an experimental mouse model of urinary tract infection (UTI). Reduced bacterial counts were found in the bladder (P .... coli colonization of the bladder in an experimental mouse model of urinary tract infection and that the organic acids are active agents....

  13. Heavy Metal Removal from Commercially-available Fruit Juice Packaged Products by Citric Acid

    Directory of Open Access Journals (Sweden)

    Shabnam Mohammadi

    2015-03-01

    Full Text Available There has been an increasing trend in the production and consumption of local and imported fruit juices in Iran. The presence of impurities and foreign matter in finished products for human consumption is of great concern because they present health hazards when they exceed beneficial limits. The manufacture of juices requires special attention in terms of purity and the sources of water and its purification are crucial for maintaining quality and safety. Biosorption can be defined as the removal of metal or metalloid species, compounds and particulates from solution by biological material. citric acid content of beverages may be useful in nutrition therapy for calcium urolithiasis, achieving therapeutic urinary citrate concentration is one clinical target in the medical management of calcium urolithiasis. Information on the citric acid content of fruit juices and commercially-available formulations is not widely known. Levels of heavy metals: Lead, Cadmium and Nickel in 180 selected fruit juice commercially available packaged samples (Pineapple, Orange, Mango, Tropical, Cherry& Grape purchased from Tehran local Market in 2014. Heavy metals were determined using atomic absorption spectrophotometer (AAS by wet digestion method in Pharmaceutical Sciences Branch, Islamic Azad University Tehran-Iran. From the obtained result Ni, Cd and Pb were detectable in 85% of samples especially in Mango and Tropical juices. The efficiency removal of Nickel, lead and Cadmium and neutralization of calculus contain of juice by Citric acid as a chelating were carried out by using of Atomic Absorption Spectrophotometry technique. The result demonstrated the complexation formulating between the citric acid and heavy metals. The high efficiency of Citric acid played an important role in removal of lead and cadmium in addition to this removal were increased by increasing the citric acid. The enhancing of citric acid in removal of lead and cadmium caused to create a

  14. Role of Ascorbic Acid on Germination Indexes and Enzyme Activity of Vicia faba Seeds Grown under Salinity Stress

    Directory of Open Access Journals (Sweden)

    Awatif A. Mohsen

    2014-08-01

    Full Text Available The present work aimed to investigate changes in growth and some metabolic activities in NaCl-stressed bean seedlings, and assessing the role of ascorbic acid to alleviate these changes. The germination was carried out to study the response of presoaked faba bean seeds (Vicia faba cv. Misr 2 in freshly prepared ascorbic acid (50 ppm ≈ 0.3 mM; as recommended dose as described by El-Tayeb, 1995 or distilled water (control for 4 hrs at natural environmental conditions, to salinity stress during germination period. The radicle and plumule lengths were inhibited at high dose of NaCl but, ascorbic acid application to salt-treated seeds seemed to increase radicle and plumule elongation. The radicle and plumule fresh and dry weights were gradually decreased with increasing NaCl concentrations but, a noticeable increase of radicle and plumule fresh and dry weights were reached in seedlings treated with ascorbic acid. The pigment biosynthesis was substantially affected by salt treatment. Addition of ascorbic acid to stressed seedlings more or less furthered the inhibitory effects of salinity. Salinity enhanced the accumulation of reducing sugars in both radicle and plumule of Vicia faba seedlings as compared with control. Ascorbic acid treatment furthered the stimulatory effects of NaCl. Salinity gradually lowered the protein content of plumules. Ascorbic acid treatments raised the accumulation of protein contents in radicle to a great extent compared to those subjected only to NaCl. Plumule alkaloid content was lowered by low and moderate levels of NaCl. Coupling ascorbic acid to salt treated seeds induced a highly significant increase in alkaloid content of plumules compared to its corresponding controls. Sodium chloride treatments to Vicia faba seeds for two days caused a drastic suppression of α- and β-amylase activities. Ascorbic acid application to non-salinized seeds seemed without effects whereas, the salt-treated seeds showed more or less

  15. A novel nanocomposites sensor for epinephrine detection in the presence of uric acids and ascorbic acids

    Energy Technology Data Exchange (ETDEWEB)

    Lu Xiaoquan, E-mail: luxq@nwnu.edu.cn [Key Laboratory of Bioelectrochemistry and Environmental Analysis of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, LanZhou, 730070 (China); Li Yaya; Du Jie; Zhou Xibin; Xue Zhonghua; Liu Xiuhui; Wang Zhihua [Key Laboratory of Bioelectrochemistry and Environmental Analysis of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, LanZhou, 730070 (China)

    2011-08-30

    Highlights: {center_dot} A novel PPy/AuNPs/SWCNTs nanomaterials biosensor was prepared to the selective determination of EP. {center_dot} The methods we employed to prepare PPy/AuNPs/SWCNTs nanomaterials are extremely simple. {center_dot} The PPy/AuNPs/SWCNTs nanocomposites biosensor we got from the results of experiments can totally eliminate the interference from AA and distinguish EP from UA. - Abstract: A novel nanocomposites film of conducting polymers including single-walled carbon nanotubes (SWCNTs), polypyrrole (PPy) and gold nanoparticles (AuNPs) modified electrode has been applied in voltammetric sensors to detect epinephrine (EP) sensitively when ascorbic acids (AA) and uric acids (UA) exist. The nanocomposites film of conducting polymers which show an excellent electrocatalystic activity for the oxidation of EP and UA was characterized by scanning electron microscopy (SEM) and electrochemical methods. The catalytic peak currents obtained from differential pulse voltammetry (DPV) increased linearly with increasing EP concentrations in the range of 4.0 x 10{sup -9}-1.0 x 10{sup -7} M with a detection limit of 2.0 x 10{sup -9} M (S/N = 3), respectively. The results showed that the nanocomposites of conducting polymers can selectively determine EP in the coexistence of a large amount of UA and AA. In addition, the sensor exhibited excellent sensitivity, selectivity and stability. The PPy/AuNPs/SWCNTs nanocomposites film can also be satisfactorily used for detecting EP in epinephrine hydrochloride injection when contain AA and UA, which also shows good recovery for determination of EP in some biological fluids.

  16. Simultaneous determination of ascorbic acid, dopamine and uric acid based on tryptophan functionalized graphene

    Energy Technology Data Exchange (ETDEWEB)

    Lian, Qianwen; He, Zhifang; He, Qian; Luo, Ai; Yan, Kaiwang; Zhang, Dongxia [Key Laboratory of Bioelectrochemistry and Environmental Analysis of Gansu Province, College of Geography and Environment Science, Northwest Normal University, Lanzhou, 730070 (China); Lu, Xiaoquan, E-mail: Luxq@nwnu.edu.cn [Key Laboratory of Bioelectrochemistry and Environmental Analysis of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, 730070 (China); Zhou, Xibin, E-mail: zhouxb@nwnu.edu.cn [Key Laboratory of Bioelectrochemistry and Environmental Analysis of Gansu Province, College of Geography and Environment Science, Northwest Normal University, Lanzhou, 730070 (China)

    2014-05-01

    Highlights: • Trp-GR was synthesized by utilizing a facile ultrasonic method. • The material as prepared had well dispersivity in water and better conductivity than pure GR. • Trp-GR/GCE showed excellent potential for the determination of AA, DA and UA. • The proposed method was applied for the analysis of AA, DA and UA in real samples. - Abstract: A new type of tryptophan-functionalized graphene nanocomposite (Trp-GR) was synthesized by utilizing a facile ultrasonic method via π–π conjugate action between graphene (GR) and tryptophan (Trp) molecule. The material as prepared had well dispersivity in water and better conductivity than pure GR. The surface morphology of Trp-GR was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. The electrochemical behaviors of ascorbic acid (AA), dopamine (DA), and uric acid (UA) were investigated by cyclic voltammetry (CV) on the surface of Trp-GR. The separation of the oxidation peak potentials for AA–DA, DA–UA and UA–AA was about 182 mV, 125 mV and 307 mV, which allowed simultaneously determining AA, DA, and UA. Differential pulse voltammetery (DPV) was used for the determination of AA, DA, and UA in their mixture. Under optimum conditions, the linear response ranges for the determination of AA, DA, and UA were 0.2–12.9 mM, 0.5–110 μM, and 10–1000 μM, with the detection limits (S/N = 3) of 10.09 μM, 0.29 μM and 1.24 μM, respectively. Furthermore, the modified electrode was investigated for real sample analysis.

  17. Use of ascorbic and citric acids to increase dialyzable iron from vinal (Prosopis ruscifolia) pulp.

    Science.gov (United States)

    Bernardi, C; Freyre, M; Sambucetti, M E; Pirovani, M E

    2004-01-01

    Vinal (Prosopis ruscifolia) is an ecologically important wild leguminous tree that grows spontaneously in Argentine deforested lands, the fruit of which is consumed by humans and animals. Because considerable iron content with low to intermediate availability has been previously reported in vinal pulps, its enhancement would be of interest. Iron availability was determined as iron dialyzability using an in vitro technique. Response surface methodology was used to evaluate iron availability increase after adding ascorbic and/or citric acids to vinal pulp at different mM acid/mM Fe ratios. Those ratios ranged from 0.05:1 to 9.95:1 and from 0.5:1 to 99.5:1 for ascorbic acid/Fe (AA:Fe) and citric acid/Fe (CA:Fe), respectively. The obtained second- and first-order polynomial equations showed that AA:Fe and CA:Fe molar ratios linear terms had a significant effect on iron dialyzability increase (P iron availability to a maximum of 4.6 times. Additional confirmatory experiments were made adding the same organic acids to different vinal pulps and to a traditional cake prepared with vinal pulp called "patay." There were no significant differences (p > 0.05) between predicted values obtained by the model and experimental results.

  18. Color of berry and juice of 'Isabel' grape treated with abscisic acid in different ripening stages

    Directory of Open Access Journals (Sweden)

    Lilian Yukari Yamamoto

    2015-12-01

    Full Text Available Abstract : The objective of this work was to evaluate the effect of (S-cis-abscisic acid (S-ABA application at different ripening stages, in increasing phenolic compounds and color of berry and juice of 'Isabel' grape (Vitis labrusca. The evaluated treatments were: control, without S-ABA application; 400 mg L-1S-ABA applied 7 days before veraison (DBV + 400 mg L-1S-ABA at 35 days after first application (DAFA; 400 mg L-1S-ABA applied at veraison (V + 400 mg L-1S-ABA at 35 DAFA; and 400 mg L-1S-ABA applied 7 days after veraison (DAV + 400 mg L-1S-ABA at 35 DAFA. There was no difference among treatments regarding the physical characteristics of berries and clusters, as well as total polyphenols in berry and juice. However, there was an increase in total anthocyanins in berry and juice with S-ABA application. Colorimetric variables indicated the increase in color of berry treated with S-ABA. Juices produced from grapes treated with S-ABA were more appreciated by tasters. The treatments with 400 mg L-1S-ABA applied 7 days before, during, or 7 days after veraison, combined with an additional application 35 days after the first one, increment total anthocyanin concentration and color of berry and juice of 'Isabel' grape, with better juice acceptance, without affecting total polyphenol concentration.

  19. Microcalorimetric Investigation on the Kinetics of the Oxidation of Ascorbic Acid with Hydrogen Peroxide

    Institute of Scientific and Technical Information of China (English)

    MENG,Xiang-Guang(孟祥光); KOU,Xing-Ming(寇兴明); XIE,Jia-Qing(谢家庆); DU,Juan(杜娟); ZENG,Xian-Cheng(曾宪诚)

    2004-01-01

    Based on the thermokinetic theory, a novel thermokinetic research method-self-function regression method,which could be used to determine the kinetic parameters k1, k2 and k 1 of the complex reaction:B+C(k1 k-1)Ik2→ P, was proposed in this paper. The kinetics of the reaction of ascorbic acid (H2A) with hydrogen peroxide was investigated at pH=5-7 and T=298.15 K, and the kinetic parameters k1, k 2 and k-1 were obtained with this method. The kinetics of the reaction was investigated in detail. The kinetic parameters of the oxidation of ascorbic monoanion (HA) and ascorbic dianion (A2-) with hydrogen peroxide were 3.33 × 10-3 s-1 and 25.48 s-1 at 298.15 K, respectively. The molar enthalpy change for the reaction was -554.64 kJ · mol-1 in phosphate buffer solution at pH 7 and at 298.15 K.

  20. Commercial scale pulsed electric field processing of tomato juice.

    Science.gov (United States)

    Min, Seacheol; Jin, Z Tony; Zhang, Q Howard

    2003-05-21

    Effects of commercial scale pulsed electric field (PEF) processing on the quality of tomato juice were studied and compared with those of thermal processing. Tomato juice was prepared by hot break at 88 degrees C for 2 min or by cold break at 68 degrees C for 2 min and then thermally processed at 92 degrees C for 90 s or PEF processed at 40 kV/cm for 57 micros. Thermally processed, PEF processed, and unprocessed control juices were packed into 50 mL sterilized polypropylene tubes in a sanitary glovebox and stored at 4 degrees C for 112 days. Both thermally and PEF processed juices showed microbial shelf life at 4 degrees C for 112 days. The lipoxygenase activities of thermally and PEF processed juices were 0 and 47%, respectively. PEF processed juice retained more ascorbic acid than thermally processed juice at 4 degrees C for 42 days (p Brix, pH, or viscosity between thermally and PEF processed juices during the storage (p > 0.05). Sensory evaluations indicated that flavor and overall acceptability of PEF processed juice were preferred to those of thermally processed juice (p < 0.05).

  1. Ascorbic Acid Biosynthesis and Brackish Water Acclimation in the Euryhaline Freshwater White-Rimmed Stingray, Himantura signifer.

    Directory of Open Access Journals (Sweden)

    Samuel Z H Wong

    Full Text Available L-gulono-γ-lactone oxidase (Gulo catalyzes the last step of ascorbic acid biosynthesis, which occurs in the kidney of elasmobranchs. This study aimed to clone and sequence gulonolactone oxidase (gulo from the kidney of the euryhaline freshwater stingray, Himantura signifer, and to determine the effects of acclimation from freshwater to brackish water (salinity 20 on its renal gulo mRNA expression and Gulo activity. We also examined the effects of brackish water acclimation on concentrations of ascorbate, dehydroascorbate and ascorbate + dehydroascorbate in the kidney, brain and gill. The complete cDNA coding sequence of gulo from the kidney of H. signifer contained 1323 bp coding for 440 amino acids. The expression of gulo was kidney-specific, and renal gulo expression decreased significantly by 67% and 50% in fish acclimated to brackish water for 1 day and 6 days, respectively. There was also a significant decrease in renal Gulo activity after 6 days of acclimation to brackish water. Hence, brackish water acclimation led to a decrease in the ascorbic acid synthetic capacity in the kidney of H. signifer. However, there were significant increases in concentrations of ascorbate and ascorbate + dehydroascorbate in the gills (after 1 or 6 days, and a significant increase in the concentration of ascorbate and a significant decrease in the concentration of dehydroascorbate in the brain (after 1 day of fish acclimated to brackish water. Taken together, our results indicate that H. signifer might experience greater salinity-induced oxidative stress in freshwater than in brackish water, possibly related to its short history of freshwater invasion. These results also suggest for the first time a possible relationship between the successful invasion of the freshwater environment by some euryhaline marine elasmobranchs and the ability of these elasmobranchs to increase the capacity of ascorbic acid synthesis in response to hyposalinity stress.

  2. Ascorbic Acid Biosynthesis and Brackish Water Acclimation in the Euryhaline Freshwater White-Rimmed Stingray, Himantura signifer.

    Science.gov (United States)

    Wong, Samuel Z H; Ching, Biyun; Chng, You R; Wong, Wai P; Chew, Shit F; Ip, Yuen K

    2013-01-01

    L-gulono-γ-lactone oxidase (Gulo) catalyzes the last step of ascorbic acid biosynthesis, which occurs in the kidney of elasmobranchs. This study aimed to clone and sequence gulonolactone oxidase (gulo) from the kidney of the euryhaline freshwater stingray, Himantura signifer, and to determine the effects of acclimation from freshwater to brackish water (salinity 20) on its renal gulo mRNA expression and Gulo activity. We also examined the effects of brackish water acclimation on concentrations of ascorbate, dehydroascorbate and ascorbate + dehydroascorbate in the kidney, brain and gill. The complete cDNA coding sequence of gulo from the kidney of H. signifer contained 1323 bp coding for 440 amino acids. The expression of gulo was kidney-specific, and renal gulo expression decreased significantly by 67% and 50% in fish acclimated to brackish water for 1 day and 6 days, respectively. There was also a significant decrease in renal Gulo activity after 6 days of acclimation to brackish water. Hence, brackish water acclimation led to a decrease in the ascorbic acid synthetic capacity in the kidney of H. signifer. However, there were significant increases in concentrations of ascorbate and ascorbate + dehydroascorbate in the gills (after 1 or 6 days), and a significant increase in the concentration of ascorbate and a significant decrease in the concentration of dehydroascorbate in the brain (after 1 day) of fish acclimated to brackish water. Taken together, our results indicate that H. signifer might experience greater salinity-induced oxidative stress in freshwater than in brackish water, possibly related to its short history of freshwater invasion. These results also suggest for the first time a possible relationship between the successful invasion of the freshwater environment by some euryhaline marine elasmobranchs and the ability of these elasmobranchs to increase the capacity of ascorbic acid synthesis in response to hyposalinity stress.

  3. Computational study on transfer of L-ascorbic acid by UlaA through Escherichia coli membrane.

    Science.gov (United States)

    Faghih-Mirzaee, Ehsan; Dehestani, Maryam; Zeidabadinejad, Leila

    2017-06-01

    In this study, the transfer of L-ascorbic acid by UlaA through Escherichia coli (E. coli) membrane was evaluated using density functional theory (DFT), molecular docking, and molecular dynamics (MD) simulation methods. DFT calculations at the B3lyp/6[Formula: see text]311[Formula: see text]G(p,d) level were performed to investigate the interaction properties and molecular descriptors. The physical properties, such as chemical potential, chemical hardness, and chemical electrophilicity of all studied molecules, were investigated. Natural population analysis was employed to describe the state of charge transfer between interactions using the natural bond orbital (NBO). The atoms in molecules (AIM) theory was used to examine the properties of the bond critical points such as their electron densities and Laplacians. Molecular docking studies showed that L-ascorbic acid was bounded to the internal cavity of UlaA. It was found that there were some hydrogen bond interactions between L-ascorbic acid and active sites of UlaA. The results of the MD simulation showed that the root mean square deviation (RMSD) of UlaA and L-ascorbic acid bound-UlaA reached equilibrium after 3.7[Formula: see text]ns. An evaluation of the radius of gyration ([Formula: see text]) revealed that UlaA and L-ascorbic acid bound-UlaA were stabilized around 10,000[Formula: see text]ns. Finally, analysis of the RMS fluctuations suggested that the structure of the L-ascorbic acid binding site remained approximately rigid during simulation. All obtained results shed light on the special manner of L-ascorbic acid transfer through E. coli membrane, and confirmed the results of previous studies on this issue.

  4. Varietal blends as a way of optimizing and preserving the anthocyanin content of pomegranate (Punica granatum L.) juices.

    Science.gov (United States)

    Mena, Pedro; Martí, Nuria; García-Viguera, Cristina

    2014-07-23

    Anthocyanins are unstable compounds prone to degradation during storage of pomegranates juices, leading to disadvantageous color changes. Blending varietal pomegranate juices could be useful not only to preserve the genuine characteristics of fresh juices but also to study different factors affecting anthocyanin stability while maintaining to the utmost the matrix studied. The effects of critical factors such as anthocyanin concentration, pH, and endogenous ascorbic acid on pigment integrity were assessed through the study of the degradation kinetics of pomegranate phytochemicals in blended juices made from two distinct cultivars ('Wonderful' and 'Mollar de Elche'). Pigment concentration and pH were the factors affecting anthocyanin stability, whereas ascorbic acid did not alter the degradation of anthocyanins. These results contributed to the definition of the so-called "cultivar effect" and to preserving to a great extent the anthocyanin load and color characteristics of fresh varietal juices, avoiding phytochemical degradation and browning development during storage.

  5. Partial characterization of chayotextle starch-based films added with ascorbic acid encapsulated in resistant starch.

    Science.gov (United States)

    Martínez-Ortiz, Miguel A; Vargas-Torres, Apolonio; Román-Gutiérrez, Alma D; Chavarría-Hernández, Norberto; Zamudio-Flores, Paul B; Meza-Nieto, Martín; Palma-Rodríguez, Heidi M

    2017-05-01

    Chayotextle starch was modified by subjecting it to a dual treatment with acid and heating-cooling cycles. This caused a decrease in the content of amylose, which showed values of 30.22%, 4.80%, 3.27% and 3.57% for native chayotextle starch (NCS), starch modified by acid hydrolysis (CMS), and CMS with one (CMS1AC) and three autoclave cycles (CMS3AC), respectively. The percentage of crystallinity showed an increase of 36.9%-62% for NCS and CMS3AC. The highest content of resistant starch (RS) was observed in CMS3AC (37.05%). The microcapsules were made with CMS3AC due to its higher RS content; the total content of ascorbic acid of the microcapsules was 82.3%. The addition of different concentrations of CMS3AC microcapsules (0%, 2.5%, 6.255% and 12.5%) to chayotextle starch-based films (CSF) increased their tensile strength and elastic modulus. The content of ascorbic acid and RS in CSF was ranged from 0% to 59.4% and from 4.84% to 37.05% in the control film and in the film mixed with CMS3AC microcapsules, respectively. Water vapor permeability (WVP) values decreased with increasing concentrations of microcapsules in the films. Microscopy observations showed that higher concentrations of microcapsules caused agglomerations due their poor distribution in the matrix of the films. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. MEMPELAJARI KARAKTERISTIK SARI BUAH DARI MENGKUDU (Morinda citrifolia Linn. YANG DIHASILKAN MELALUI FERMENTASI [Characteristic of Noni (Morinda citrifolia Linn Fruit Juice Produced by Fermentation

    Directory of Open Access Journals (Sweden)

    Ivonne P Kusuma3

    2003-08-01

    Full Text Available Fermentation is one of the methods to get noni juice. In this research, noni is fermented in hanged system and submerged system for 1, 2, 3, and 4 weeks. The result showed the longer fermentation increased pH, alcohol content, turbidity, viscosity, microbial content, and decrease ascorbic acid and acid content, soluble solid content, color and flavor acceptance. Differennt system fermentation affected percent yield, soluble solid content, turbidity of juice, panels opinion to color significantly. Noni juice of submerged system has higher percent yield, higher soluble solid content, turbidity, but provided lighter color than noni juice of hanged system. Juice of submerged system is better than hanged system. Juice from three weeks fermentation indicated changes of metabolism activity which is shown by some characteristic changes. Fruit juice made by submerged fermentation system had more diverse compounds than fruit juice without fermentation.

  7. The Effect of Ascorbic Acid Treatment on Viability and Vigor Maize (Zea mays L. Seedling under Drought Stress

    Directory of Open Access Journals (Sweden)

    HAMIDAH HAMAMA

    2010-09-01

    Full Text Available This study was conducted in the laboratory and the field to examine the effects of ascorbic acid treatment on germination and seedling growth under drought stress. The laboratory works consisted of two experiments and were designed to determine the critical osmotic potential of maize and to determine the optimum ascorbic acid concentration. The field study was designed to examine the effects of soaking seed in ascorbic acid on seedling growth under drought stress. Drought condition was simulated by PEG-6000 and regulation of water treatment. During the first experiment, interactions of both osmotic potential and varieties were significant at all variables. Germination percentage and speed of germination were significantly decreased by increasing of osmotic potential. The second experiment showed that interactions of both factors were significant at all variables except vigor index, the length of shoot, primary, and seminal root. The results showed that the ascorbic acid treatment improved the germination percentage, the speed of germination and the vigor index compared with the control, besides the increase in length of shoot, primary and seminal root and number of seminal root. However, the best result was showed by 55 mM ascobic acid. The result of field experiment showed that interactions were not always significant and 55 mM ascorbic acid treatment increased the seedling height, the number of leaves and leaf area but it had no effect on the water deficit and the root length.

  8. Regulation of Water Deficit-Induced Abscisic Acid Accumulation by Apoplastic Ascorbic Acid in Maize Seedlings

    Institute of Scientific and Technical Information of China (English)

    Jian-Fang HU; Gui-Fen LI; Zhi-Hui GAO; Lin CHEN; Hui-Bo REN; Wen-Suo JIA

    2005-01-01

    Water deficit-induced abscisic acid (ABA) accumulation is one of the most important stress signaling pathways in plant cells. Redox regulation of cellular signaling has currently attracted particular attention, but much less is known about its roles and mechanisms in plant signaling. Herein, we report that water deficit-induced ABA accumulation could be regulated by ascorbic acid (AA)-controlled redox status in leave apoplast. The AA content in non-stressed leaves was approximately 3 μmol/g FW, corresponding to a mean concentration of 3 mmol/L in a whole cell. Because AA is mainly localized in the cytosol and chloroplasts, the volume of which is much smaller than that of the whole cell, AA content in cytosolic and chloroplast compartments should be much higher than 3 mmol/L. Water deficit-induced ABA accumulation in both leaf and root tissues of maize seedlings was significantly inhibited by AA and reduced glutathione (GSH) at concentrations of 500 μmol/L and was completely blocked by 50 mmol/L AA and GSH. These results suggest that the AA-induced inhibition of ABA accumulation should not occur at sites where AA exists in high concentrations. Although water deficit led to a small increase in the dehydroascorbic acid (DHA) content, no significant changes in AA content were observed in either leaf or root tissues. When compared with the whole leaf cell, the AA content in the apoplastic compartment was much lower (i.e.approximately 70 nmol/g FW, corresponding to 0.7 mmol/L). Water deficit induced a significant decrease (approximately 2.5-fold) in the AA content and an increase (approximately 3.4-fold) in the DHA content in the apoplastic compartment, thus leading to a considerably decreased redox status there, which may have contributed to the relief of AA-induced inhibition of ABA accumulation, alternatively, promoting water deficit-induced ABA accumulation. Reactive oxygen species (ROS) could not mimic water deficit in inducing ABA accumulation, suggesting that

  9. Redifferentiation of Human Gastric Cancer Cells Induced by Ascorbic Acid and Sodium Selenite

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye exclusion method was used to determine the cell growth curve and mitotic index, cell electrophoresis and colonogenic potential were used as the indexes of redifferentiation. In order to find out the mechanisms of redifferentiation, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) were assayed, the content of malondialdehyde (MDA), reduced glutathione (GSH) and H2O2 were evaluated. Results After treatment with AA 3 mol/L + SS 2μmol/L, the growth rate and mitotic index of human gastric cancer cells (MGc-803) decreased remarkably. The indexes related with cell malignancy were alleviated. For example, cell surface charge was obviously decreased, the electrophoresis rate was dropped from 2.21 to 1.15μm@s-1@V-1@cm-1. The indexes related with cell redifferentiation were promoted. For example, the colonogenic potential was decreased to 93.5%. These results indicated that redifferentiation of human gastric cancer cells was successfully induced by AA + SS. The activities of SOD and GPX were significantly higher, while the activity of CAT was slower in treated group than that in the control. The content of MDA was slightly decreased, GSH was sharply decreased, and H2O2 content was dramatically increased. Conclusion These results indicated that combination of ascorbic acid and sodium selenite may induce the redifferentiation of human gastric cancer cells and inhibit cell growth by virtue of enhancing the activities of antioxidative enzymes and inducing the formation of H2O2, and altering the cell redox status. Combination of ascorbic acid and sodium selenite may be a potent anticancer agent for human gastric cancer.

  10. Acute Copper and Ascorbic Acid Supplementation Inhibits Non-heme Iron Absorption in Humans.

    Science.gov (United States)

    Olivares, Manuel; Figueroa, Constanza; Pizarro, Fernando

    2016-08-01

    The objective of the study is to determine the effect of copper (Cu) plus the reducing agent ascorbic acid (AA) on the absorption of non-heme iron (Fe). Experimental study with block design in which each subject was his own control. After signing an informed consent, 14 adult women using an effective method of contraception and negative pregnancy test received 0.5 mg Fe, as ferrous sulfate, alone or with Cu, as copper sulfate, plus ascorbic acid (AA/Cu 2/1 molar ratio) at 4/1; 6/1 and 8/1 Cu/Fe molar ratios as an aqueous solution on days 1, 2, 14, and 15 of the study. Fe absorption was assessed by erythrocyte incorporation of iron radioisotopes (55)Fe and (59)Fe. Geometric mean (range ± SD) absorption of Fe at 4/1 and 6/1 Cu/Fe molar ratios (and AA/Cu 2/1 molar ratio) and Fe alone was 57.4 % (35.7-92.1 %), 64.2 % (45.8-89.9 %), and 38.8 % (20.4-73.8 %), respectively (ANOVA for repeated measures p absorption; however, Fe absorption at Cu/Fe 8/1 molar ratio was 47.3 % (27.7-80.8) (p = NS compared with Fe alone). It was expected that Fe absorption would have been equal or greater than at 4/1 and 6/1 molar ratios. Copper in the presence of ascorbic acid inhibits non-heme Fe absorption at Cu/Fe 8/1 molar ratio.

  11. Nonlocal nonlinear refractive index of gold nanoparticles synthesized by ascorbic acid reduction: comparison of fitting models.

    Science.gov (United States)

    Balbuena Ortega, A; Arroyo Carrasco, M L; Méndez Otero, M M; Gayou, V L; Delgado Macuil, R; Martínez Gutiérrez, H; Iturbe Castillo, M D

    2014-12-12

    In this paper, the nonlinear refractive index of colloidal gold nanoparticles under continuous wave illumination is investigated with the z-scan technique. Gold nanoparticles were synthesized using ascorbic acid as reductant, phosphates as stabilizer and cetyltrimethylammonium chloride (CTAC) as surfactant agent. The nanoparticle size was controlled with the CTAC concentration. Experiments changing incident power and sample concentration were done. The experimental z-scan results were fitted with three models: thermal lens, aberrant thermal lens and the nonlocal model. It is shown that the nonlocal model reproduces with exceptionally good agreement; the obtained experimental behaviour.

  12. Nonenzymatic amperometric sensor for ascorbic acid based on hollow gold/ruthenium nanoshells.

    Science.gov (United States)

    Jo, Ara; Kang, Minkyung; Cha, Areum; Jang, Hye Su; Shim, Jun Ho; Lee, Nam-Suk; Kim, Myung Hwa; Lee, Youngmi; Lee, Chongmok

    2014-03-28

    We report a new nonenzymatic amperometric detection of ascorbic acid (AA) using a glassy carbon (GC) disk electrode modified with hollow gold/ruthenium (hAu-Ru) nanoshells, which exhibited decent sensing characteristics. The hAu-Ru nanoshells were prepared by the incorporation of Ru on hollow gold (hAu) nanoshells from Co nanoparticle templates, which enabled AA selectivity against glucose without aid of enzyme or membrane. The structure and electrocatalytic activities of the hAu-Ru catalysts were characterized by spectroscopic and electrochemical techniques. The hAu-Ru loaded on GC electrode (hAu-Ru/GC) showed sensitivity of 426 μA mM(-1) cm(-2) (normalized to the GC disk area) for the linear dynamic range of <5 μM to 2 mM AA at physiological pH. The response time and detection limit were 1.6 s and 2.2 μM, respectively. Furthermore, the hAu-Ru/GC electrode displayed remarkable selectivity for ascorbic acid over all potential biological interferents, including glucose, uric acid (UA), dopamine (DA), 4-acetamidophenol (AP), and nicotinamide adenine dinucleotide (NADH), which could be especially good for biological sensing.

  13. Kolaviron and L-Ascorbic Acid Attenuate Chlorambucil-Induced Testicular Oxidative Stress in Rats

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    Ebenezer Tunde Olayinka

    2014-01-01

    Full Text Available Chlorambucil (4-[4-[bis(2-chloroethylamino]phenyl]butanoic acid is an alkylating agent, indicated in chronic lymphocytic leukaemia. Kolaviron (KV, a biflavonoid complex from Garcinia kola, and L-ascorbic acid (AA are known to protect against oxidative damage in vivo. This study evaluates the protective capacity of KV and AA on chlorambucil-induced oxidative stress in the testes of rat. Twenty male Wistar rats (180–200 g were randomized into four groups: I: control, II: chlorambucil (0.2 mg/kg b.w., III: 0.2 mg/kg chlorambucil and 100 mg/kg KV, and IV: 0.2 mg/kg chlorambucil and 100 mg/kg AA. After 14 days of treatments, results indicated that chlorambucil caused significant reduction (P<0.05 in testicular vitamin C and glutathione by 32% and 39%, respectively, relative to control. Similarly, activities of testicular GST, SOD, and CAT reduced significantly by 48%, 47%, and 49%, respectively, in chlorambucil-treated rats relative to control. Testicular MDA and activities of ALP, LDH, and ACP were increased significantly by 53%, 51%, 64%, and 70%, respectively, in the chlorambucil-treated rat. However, cotreatment with KV and AA offered protection and restored the levels of vitamin C, GSH, and MDA as well as SOD, CAT, GST, ACP, ALP, and LDH activities. Overall, kolaviron and L-ascorbic acid protected against chlorambucil-induced damage in the testes of the rat.

  14. Betalain, Acid Ascorbic, Phenolic Contents and Antioxidant Properties of Purple, Red, Yellow and White Cactus Pears

    Science.gov (United States)

    Sumaya-Martínez, María Teresa; Cruz-Jaime, Sandra; Madrigal-Santillán, Eduardo; García-Paredes, Juan Diego; Cariño-Cortés, Raquel; Cruz-Cansino, Nelly; Valadez-Vega, Carmen; Martinez-Cardenas, Leonardo; Alanís-García, Ernesto

    2011-01-01

    Commercialization of cactus pears based on their antioxidant properties can generate competitive advantages, and these can turn into business opportunities and the development of new products and a high-value ingredient for the food industry. This work evaluated the antioxidant activities (1,1-diphenyl-2-picrylhydrazyl radical-scavenging, protection against oxidation of a β-carotene-linoleic acid emulsion, and iron (II) chelation), the content of total phenolic compounds, ascorbic acid, betacyanin, betaxanthin and the stability of betacyanin pigments in presence of Cu (II)-dependent hydroxyl radicals (OH•), in 18 cultivars of purple, red, yellow and white cactus pear from six Mexican states. Our results indicated that the antiradical activities from yellow and white cactus pear cultivars were not significantly different (p < 0.05) and were lower than the average antiradical activities in red and purple cultivars. The red cactus pear from the state of Zacatecas showed the highest antioxidant activity. The free radical scavenging activity for red cactus pears was significantly correlated (p < 0.05) to the concentration of total phenolic compounds (R2 = 0.90) and ascorbic acid (R2 = 0.86). All 18 cultivars of cactus pears studied showed significant chelating activity of ferrous ions. The red and purple cactus pears showed a great stability when exposed to OH•. PMID:22072899

  15. Betalain, Acid Ascorbic, Phenolic Contents and Antioxidant Properties of Purple, Red, Yellow and White Cactus Pears

    Directory of Open Access Journals (Sweden)

    Leonardo Martinez-Cardenas

    2011-09-01

    Full Text Available Commercialization of cactus pears based on their antioxidant properties can generate competitive advantages, and these can turn into business opportunities and the development of new products and a high-value ingredient for the food industry. This work evaluated the antioxidant activities (1,1-diphenyl-2-picrylhydrazyl radical-scavenging, protection against oxidation of a β-carotene-linoleic acid emulsion, and iron (II chelation, the content of total phenolic compounds, ascorbic acid, betacyanin, betaxanthin and the stability of betacyanin pigments in presence of Cu (II-dependent hydroxyl radicals (OH•, in 18 cultivars of purple, red, yellow and white cactus pear from six Mexican states. Our results indicated that the antiradical activities from yellow and white cactus pear cultivars were not significantly different (p < 0.05 and were lower than the average antiradical activities in red and purple cultivars. The red cactus pear from the state of Zacatecas showed the highest antioxidant activity. The free radical scavenging activity for red cactus pears was significantly correlated (p < 0.05 to the concentration of total phenolic compounds (R2 = 0.90 and ascorbic acid (R2 = 0.86. All 18 cultivars of cactus pears studied showed significant chelating activity of ferrous ions. The red and purple cactus pears showed a great stability when exposed to OH•.

  16. Long-term ascorbic acid administration causes anticonvulsant activity during moderate and long-duration swimming exercise in experimental epilepsy.

    Science.gov (United States)

    Tutkun, Erkut; Arslan, Gokhan; Soslu, Recep; Ayyildiz, Mustafa; Agar, Erdal

    2015-01-01

    The benefits of regular exercise on brain health are undeniable. Long-term exercise increases the production of reactive oxygen species in brain. Therefore, athletes often consume antioxidant supplements to remedy exercise-related damage and fatigue during exercise. The aim of this study is to evaluate the role of ascorbic acid in the effects of different intensities of swimming exercise on the brain susceptibility to experimental epilepsy in rats. Ascorbic acid was administered intraperitoneally (ip) during three different swimming exercise programme for 90 days (15 min, 30 min, 90 min/day). The anticonvulsant activity regarding the frequency of epileptiform activity appeared in the 80 min after 500 units intracortical penicillin injection in 30 min and 90 min/day exercise groups. The administration of ascorbic acid (100 mg/kg, ip) did not alter the anticonvulsant properties seen in the in short-duration (15 min/day) swimming exercise group. The amplitude of epileptiform activity also became significant in the 110 and 120 min after penicillin injection in the moderate (30 min/day) and long duration (60 min/day) groups, respectively. The results of the present study provide electrophysiologic evidence that long-term administration of ascorbic acid causes anticonvulsant activities in the moderate and long-duration swimming exercise. Antioxidant supplementation such as ascorbic acid might be suggested for moderate and long-duration swimming exercise in epilepsy.

  17. Modelling the effects of transglutaminase and L-ascorbic acid on substandard quality wheat flour by response surface methodology

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    Šimurina Olivera D.

    2014-01-01

    Full Text Available In recent decade, there have been observed extreme variations in climatic conditions which in combination with inadequate agro techniques lead to decreased quality of mercantile wheat, actally flour. The application of improvers can optimise the quality of substandard wheat flour. This paper focuses to systematic analysis of individual and interaction effects of ascorbic acid and transglutaminase as dough strengthening improvers. The effects were investigated using the Response Surface Methodology. Transglutaminase had much higher linear effect on the rheological and fermentative properties of dough from substandard flour than L-ascorbic acid. Both transglutaminase and L-ascorbic acid additions had a significant linear effect on the increase of bread specific volume. Effects of transglutaminase and ascorbic acid are dependent on the applied concentrations and it is necessary to determine the optimal concentration in order to achieve the maximum quality of the dough and bread. Optimal levels of tested improvers were determined using appropriate statistical techniques which applied the desirability function. It was found that the combination of 30 mg/kg of transglutaminase and 75.8 mg/kg of L-ascorbic acid achieved positive synergistic effect on rheological and fermentative wheat dough properties, as well on textural properties and specific volume of bread made from substandard quality flour.

  18. Immunomodulatory Role of Ocimum gratissimum and Ascorbic Acid against Nicotine-Induced Murine Peritoneal Macrophages In Vitro

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    Santanu Kar Mahapatra

    2011-01-01

    Full Text Available The aim of this present study was to evaluate the immune functions and immune responses in nicotine-induced (10 mM macrophages and concurrently establish the immunomodulatory role of aqueous extract of Ocimum gratissimum (Ae-Og and ascorbic acid. In this study, nitrite generations and some phenotype functions by macrophages were studied. Beside that, release of Th1 cytokines (TNF-α, IL-12 and Th2 cytokines (IL-10, TGF-β was measured by ELISA, and the expression of these cytokines at mRNA level was analyzed by real-time PCR. Ae-Og, at a dose of 10 μg/mL, significantly reduced the nicotine-induced NO generation and iNOSII expression. Similar kinds of response were observed with supplementation of ascorbic acid (0.01 mM. The administration of Ae-Og and ascorbic acid increased the decreased adherence, chemotaxis, phagocytosis, and intracellular killing of bacteria in nicotine-treated macrophages. Ae-Og and ascorbic acid were found to protect the murine peritoneal macrophages through downregulation of Th1 cytokines in nicotine-treated macrophages with concurrent activation of Th2 responses. These findings strongly enhanced our understanding of the molecular mechanism leading to nicotine-induced suppression of immune functions and provide additional rationale for application of anti-inflammatory therapeutic approaches by O. gratissimum and ascorbic acid for different inflammatory disease prevention and treatment during nicotine toxicity.

  19. Electrochemical Preparation of a Molecularly Imprinted Polypyrrole-modified Pencil Graphite Electrode for Determination of Ascorbic Acid

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    Yücel Sahin

    2008-09-01

    Full Text Available A molecularly imprinted polymer (MIP polypyrrole (PPy-based film was fabricated for the determination of ascorbic acid. The film was prepared by incorporation of a template molecule (ascorbic acid during the electropolymerization of pyrrole onto a pencil graphite electrode (PGE in aqueous solution using a cyclic voltammetry method. The performance of the imprinted and non-imprinted (NIP films was evaluated by differential pulse voltammetry (DPV. The effect of pH, monomer and template concentrations, electropolymerization cycles and interferents on the performance of the MIP electrode was investigated and optimized. The molecularly imprinted film exhibited a high selectivity and sensitivity toward ascorbic acid. The DPV peak current showed a linear dependence on the ascorbic acid concentration and a linear calibration curve was obtained in the range of 0.25 to 7.0 mM of ascorbic acid with a correlation coefficient of 0.9946. The detection limit (3σ was determined as 7.4x10-5 M (S/N=3. The molecularly-imprinted polypyrrole-modified pencil graphite electrode showed a stable and reproducible response, without any influence of interferents commonly existing in pharmaceutical samples. The proposed method is simple and quick. The PPy electrodes have a low response time, good mechanical stability and are disposable simple to construct.

  20. Ascorbic acid enhanced activation of oxygen by ferrous iron: A case of aerobic degradation of rhodamine B.

    Science.gov (United States)

    Hou, Xiaojing; Shen, Wenjuan; Huang, Xiaopeng; Ai, Zhihui; Zhang, Lizhi

    2016-05-05

    Molecular oxygen activation by ferrous ions (Fe(II)) in aqueous solution could generate reactive oxygen species (ROS) with high oxidation potential via reaction between Fe(II) and oxygen molecules (Fe(II)/air), however, ROS yielded in the Fe(II)/air process is insufficient for removal of organic pollutants due to the irreversible ferric ions (Fe(III)) accumulation. In this study, we demonstrate that ascorbic acid (AA) could enhance ROS generation via oxygen activation by ferrous irons (AA/Fe(II)/air) and thus improve the degradation of rhodamine (RhB) significantly. It was found that the first-order aerobic degradation rate of RhB in the AA/Fe(II)/air process in the presence of ascorbic acid is more than 4 times that of the Fe(II)/Air system without adding ascorbic acid. The presence of ascorbic acid could relieve the accumulation of Fe(III) by reductive accelerating the Fe(III)/Fe(II) cycles, as well as lower the redox potential of Fe(III)/Fe(II) through chelating effect, leading to enhanced ROS generation for promoting RhB degradation. This study not only sheds light on the effect of ascorbic acid on aerobic Fe(II) oxidation, but also provides a green method for effective remediation of organic pollutants.

  1. Effect of cultivation line and peeling on food composition, taste characteristic, aroma profile, and antioxidant activity of Shiikuwasha (Citrus depressa Hayata) juice.

    Science.gov (United States)

    Asikin, Yonathan; Fukunaga, Hibiki; Yamano, Yoshimasa; Hou, De-Xing; Maeda, Goki; Wada, Koji

    2014-09-01

    Shiikuwasha (Citrus depressa Hayata) juice from four main cultivation lines subjected to two peeling practices (with or without peeling) were discriminated in terms of quality attributes, represented by sugar and organic acid composition, taste characteristic, aroma profile, and antioxidant activity. Shiikuwasha juice from these lines had diverse food compositions; 'Izumi kugani' juice had lower acidity but contained more ascorbic acid than that of other cultivation lines. The composition of volatile aroma components was influenced by fruit cultivation line, whereas its content was affected by peeling process (20.26-53.73 mg L(-1) in whole juice versus 0.82-1.58 mg L(-1) in flesh juice). Peeling also caused Shiikuwasha juice to be less astringent and acidic bitter and to lose its antioxidant activity. Moreover, the total phenolic and ascorbic acid content of Shiikuwasha juice positively influenced its antioxidant activity. Each fruit cultivation line had a distinct food composition, taste characteristic, and aroma profile. Peeling in Shiikuwasha juice production might reduce aftertaste, and thus might improve its palatability. Comprehensive information on the effect of cultivation line and peeling on quality attributes will be useful for Shiikuwasha juice production, and can be applied to juice production of similar small citrus fruits. © 2014 Society of Chemical Industry.

  2. Ascorbic acid Beta-Carotene and Amino acids in Capsicum (Capsicum annuum during fruit development in Himalayan Hills

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    P. C. Pant

    1984-04-01

    Full Text Available Capsicum varieties viz HC-201 & HC-202 developed at ARU, Almora took 35 days from fruit set to ripening. Results showed significant positive correlation for ascorbic acid and Beta-carotene with days to maturity. Out of eight ninhydrin positive products, only seven could be identified viz, hydroxyproline, proline, lysine, 5-alanine, arginine, threonine and methionine, at the later stages of the fruit development. All amino acids except methionine were found either absent or in traces at the earlier stages of fruit development.

  3. Efficient voltammetric discrimination of free bilirubin from uric acid and ascorbic acid by a CVD nanographite-based microelectrode.

    Science.gov (United States)

    Taurino, Irene; Van Hoof, Viviane; Magrez, Arnaud; Forró, László; De Micheli, Giovanni; Carrara, Sandro

    2014-12-01

    We report a novel electrochemical sensor based on nanographite grown on platinum microelectrodes for the determination of bilirubin in the presence of normal concentrations of albumin. The albumin is a protein with an intrinsic ability to bind the bilirubin therefore reducing the concentration of the free electroactive metabolite in human fluids. In addition, the proposed device permits the discrimination of free bilirubin from two interferents, uric acid and ascorbic acid, by the separation of their oxidation peaks in voltammetry. Preliminary measurements in human serum prove that the proposed nanostructured platform can be used to detect bilirubin.

  4. Gold Electrodes Modified with Self-Assembled Monolayers for Measuring L-Ascorbic Acid: An Undergraduate Analytical Chemistry Laboratory Experiment

    Science.gov (United States)

    Ito, Takashi; Perera, D. M. Neluni T.; Nagasaka, Shinobu

    2008-01-01

    This article describes an undergraduate electrochemistry laboratory experiment in which the students measure the L-ascorbic acid content of a real sample. Gold electrodes modified with self-assembled monolayers (SAMs) of thioctic acid and cysteamine are prepared to study the effects of surface modification on the electrode reaction of L-ascorbic…

  5. Antioxidant capacity and contents of phenols, ascorbic acid, β-carotene and lycopene in lettuce

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    Zdravković Jasmina M.

    2014-01-01

    Full Text Available The antioxidant activity of three lettuce varieties (Lactuca sativa L. Emerald, Vera and Neva, cultivated in two kinds of protected spaces, a glasshouse and a plastic greenhouse, under controlled conditions, was determined. The content of antioxidant compounds: total phenols, flavonoids, L-ascorbic acid, ß-carotene and lycopene, were determined in ethanolic extracts of the lettuce with spectrophotometric methods. The largest content of total phenols (78.98 ± 0.67 mg GAE/g of dry extract was found in ethanolic extract of the lettuce variety Neva cultivated in a plastic greenhouse, whereas the largest content of flavonoids (35.45 ± 0.95 mg RU/g of dry extract was displayed in the lettuce Emerald cultivated in a glasshouse. It was observed that the lettuce cultivated in the glasshouse contained a somewhat higher content of L-ascorbic acid than the lettuce same variety from plastic greenhouse. The content of lycopene in the examined lettuce is negligible, and the content of ß-carotene is low. On the other hand, the high content of phenolic components causes favourable antioxidant properties found in all varieties of examined lettuce. [Projekat Ministarstva nauke Republike Srbije, br. TR 31059: A new concept in breeding vegetable cultivars and hybrids designed for sustainable growing systems using biotechnological methods

  6. EXTRACTION AND QUANTITATIVE DETERMINATION OF ASCORBIC ACID FROM BANANA PEEL MUSA ACUMINATA ‘KEPOK’

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    Khairul Anwar Mohamad Said

    2016-04-01

    Full Text Available This paper discusses the extraction of an antioxidant compound, which is ascorbic acid or vitamin C, from a banana peel using an ultrasound-assisted extraction (UAE method. The type of banana used was Musa acuminata also known as “PisangKepok” in Malaysia. The investigation includes the effect of solvent/solid ratio (4.5, 5 g and 10  ml/g, sonication time (15, 30 and 45 mins and temperature variation (30 , 45  and 60oC on the extraction of ascorbic acid compounds from the banana peel to determine the best or optimum condition of the operation. Out of all extract samples analyzed by redox titration method using iodine solution, it was found that the highest yield was 0.04939 ± 0.00080 mg that resulted from an extraction at 30oC for 15 mins with 5 ml/g solvent-to-solute ratio.KEYWORDS:  Musa acuminata; ultrasound-assisted extraction; vitamin C; redox titration

  7. [Effects of ascorbic acid on the free radical formations of isoniazid and its metabolites].

    Science.gov (United States)

    Matsuki, Y; Akazawa, M; Tsuchiya, K; Sakurai, H; Kiwada, H; Goromaru, T

    1991-10-01

    By the use of electron spin resonance (ESR) spectroscopy and of spin-trapping technique, the effects of ascorbic acid on the formation of the free radical intermediates due to isoniazid (INAH) and its metabolites were investigated with a microsomal system. When alpha-(4-pyridyl 1-oxide)-N-tert butylnitrone (4-POBN) was used as a spin trapping agent, the ESR signal due to hydrazine (Hy) was formed to be most intensive among others. Therefore, it was presumed that Hy is a potent intermediate to cause an INAH-induced hepatic injury. In the presence of ascorbic acid (AA), the free radical formation of Hy, INAH and acetyl hydrazine was significantly inhibited, suggesting that AA may affect the INAH-hepatitis. By the addition of inhibitors of cytochrome P-450 like metyrapone and CO, the generation of the radical from Hy decreased, confirming that the radical is formed by the cytochrome P-450 dependent microsome systems. The 4-POBN-trapped radical species generated from Hy was presumed to be the hydrazyl radical by the results of mass spectrometry.

  8. Combined therapy of Ulmo honey (Eucryphia cordifolia and ascorbic acid to treat venous ulcers

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    Mariano del Sol Calderon

    2015-04-01

    Full Text Available OBJECTIVE: to assess the clinical effect of topical treatment using Ulmo honey associated with oral ascorbic acid in patients with venous ulcers. METHOD: longitudinal and descriptive quantitative study. During one year, 18 patients were assessed who were clinically diagnosed with venous ulcer in different stages, male and female, adult, with a mean injury time of 13 months. Ulmo honey was topically applied daily. The dressing was applied in accordance with the technical standard for advanced dressings, combined with the daily oral consumptions of 500 mg of ascorbic acid. The monitoring instrument is the assessment table of venous ulcers. RESULTS: full healing was achieved in 100% of the venous ulcers. No signs of complications were observed, such as allergies or infection. CONCLUSION: the proposed treatment showed excellent clinical results for the healing of venous ulcers. The honey demonstrated debriding and non-adherent properties, was easy to apply and remove and was well accepted by the users. The described results generated a research line on chronic wound treatment.

  9. Association of Lactobacillus crispatus with fructo-oligosaccharides and ascorbic acid in hydroxypropyl methylcellulose vaginal insert.

    Science.gov (United States)

    Vitali, Beatrice; Abruzzo, Angela; Parolin, Carola; Palomino, Rogers Alberto Ñahui; Dalena, Francesco; Bigucci, Federica; Cerchiara, Teresa; Luppi, Barbara

    2016-01-20

    The aim of this work was to develop a synbiotic vaginal insert containing the probiotic strain Lactobacillus crispatus BC5, the prebiotic substrate fructo-oligosaccharide and the antioxidant agent ascorbic acid, for the prophylaxis and therapy of vaginal infections. Mucoadhesive in situ gelling vaginal inserts based on hydroxypropyl methylcellulose were prepared by freeze-drying, stored at +2-8 °C for 90 days and characterized in terms of technological and functional properties. Complete survival of L. crispatus BC5 was found immediately after insert preparation (96.08%) as well as after 90 days of storage (95.82%) in the vaginal inserts containing fructo-oligosaccharide, ascorbic acid and skimmed milk. Synbiotic inserts showed improved mucoadhesion ability (from three- to five-fold) with respect to a standard formulation based on hydroxypropyl methylcellulose alone. Moreover, inserts allowed to modulate lactobacilli release in virtue of the different amounts of fructo-oligosaccharide. Finally, antimicrobial activity was exerted by L. crispatus BC5 released from the vaginal formulation.

  10. Hemato-biochemical responses to packing in donkeys administered ascorbic acid during the harmattan season.

    Science.gov (United States)

    Olaifa, Folashade; Ayo, Joseph Olusegun; Ambali, Suleiman Folorunsho; Rekwot, Peter Ibrahim

    2015-02-01

    Experiments were performed to investigate the effect of ascorbic acid (AA) in reducing hemato-biochemical changes in pack donkeys during the cold-dry (harmattan) season. Six experimental donkeys administered orally AA (200 mg/kg) and six control donkeys not administered ascorbic acid were subjected to packing. Blood samples were collected from all donkeys for hematological and biochemical analyses. In the control donkeys, packed cell volume (PCV), erythrocyte count and hemoglobin concentration (Hb) decreased significantly (Ppacking. In the experimental donkeys, there was no significant difference between the pre- and post-packing values of PCV, erythrocyte count and Hb. In the control donkeys, the neutrophil and neutrophil:lymphocyte ratio increased significantly (Ppacking, but in the experimental donkeys, the pre- and post-packing values were not significantly different. The eosinophil count increased significantly (Ppacking. In conclusion, packing exerted significant adverse effects on the hematological parameters ameliorated by AA administration. AA may modulate neutrophilia and induce a considerable alteration of erythroid markers in donkeys subjected to packing during the harmattan season.

  11. Comparative evaluation of polymeric and waxy microspheres for combined colon delivery of ascorbic acid and ketoprofen.

    Science.gov (United States)

    Maestrelli, F; Zerrouk, N; Cirri, M; Mura, P

    2015-05-15

    The goal of this work was to combine the ketoprofen anti-inflammatory effect with the ascorbic acid antioxidant properties for a more efficient treatment of colonic pathologies. With this aim, microspheres (MS) based on both waxy materials (ceresine, Precirol(®) and Compritol(®)) or hydrophilic biopolymers (pectine, alginate and chitosan) loaded with the two drugs were developed, physicochemically characterized and compared in terms of entrapment efficiency, in vitro release profiles, potential toxicity and drug permeation properties across the Caco-2 cell line. Waxy MS revealed an high encapsulation efficiency of ketoprofen but a not detectable entrapment of ascorbic acid, while polymeric MS showed a good entrapment efficiency of both drugs. All MS need a gastro-resistant coating, to avoid any premature release of the drugs. Ketoprofen release rate from polymeric matrices was clearly higher than from the waxy ones. In contrast, the ASC release rate was higher, due to its high hydro-solubility. Cytotoxicity studies revealed the safety of all the formulations. Transport studies showed that the ketoprofen apparent permeability increased, when formulated with the different MS. In conclusion, only polymeric MS enabled an efficient double encapsulation of both the hydrophilic and lipophilic drugs, and, in addition, presented higher drug release rate and stronger enhancer properties.

  12. Valorizing dairy waste: thermophilic biosynthesis of a novel ascorbic acid derivative.

    Science.gov (United States)

    Yang, Jingwen; Perez, Bianca; Anankanbil, Sampson; Li, Jingbo; Zhou, Ye; Gao, Renjun; Guo, Zheng

    2017-09-26

    L-ascorbic acid (L-AA) is an essential nutrient that is extremely instable and cannot be synthesized by the human body. Therefore, attempts have been done to develop biological active L-AA derivatives with improved stability. This work presents a facile, scalable and efficient enzymatic transgalactosylation of lactose to L-AA using β-glucosidase (TN0602) from Thermotoga naphthophila RKU-10. β-Glucosidase TN0602 displayshigh transgalactosylation activity at pH 5.0, 75°C and L-AA/lactose ratio 2/1, to form a novel L-AA derivative (2-O-β-D-Galactopyranosyl L-Ascorbic Acid, L-AA-Gal) with a maximal productivity of 138.88mmol L-1 in 12h, which is higher than most reports of enzymatic synthesis of L-AA-α-glucoside. Synthetic L-AA-Gal retains most of L-AA antioxidant capability and presents dramatically higher stability than L-AA in oxidative environment (Cu2+). In conclusion, this work report a new way to valorize dairy waste lactose into a novel molecule L-AA-Gal, which could be a promising L-AA derivative to be used in a wide range of applications.

  13. Investigating Ascorbic Acid Effect in Prevention of CIN in Diabetic Patients

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    Nough

    2013-06-01

    Full Text Available Introduction: Contrast induced nephropathy (CIN is one the complications resulting from coronary catheterization and is regarded as one of the reasons of acute kidney failure. Therefore, this study aimed to investigate the effect of ascorbic acid in the prevention of CIN in Yazd in 2012. Methods: This study involves a double blind clinical trial in which 90 Diabetic patients with coronary catheterization have attended. The patients were divided randomly into two groups: control group and treatment group. Demographic and clinical data were collected by a questionnaire. Treatment group received vitamin C (2 grams 2 hours before the intervention and the control groups were given 2 grams of the Placebo. The GFR (Glomerular filtration rate, BUN (Blood Urea Nitrogen, and Cr (Creatinin were measured and compared after 2-3 days. Results: The CIN in treatment group was about 3 patients (7.7% and was 7 (16.7% in the control group. Thus, no significant difference was observed; though, there was a significant difference between Cr and GFR before and after the treatment in vitamin C group (PV= 0.006, PV=0.001, but these differences were not significant in the placebo group.(PV=0.661, PV=0.747. Moreover, considering the participants’ age, sex and their primary function of kidney, a significant difference had not appeared due to the incidence of CIN between the two groups. Conclusion: Our study did not show Ascorbic Acid effects in prevention of CIN in Diabetic patients.

  14. Effects of supplemental ascorbic acid on humeral immune response in broilers reared under heat-stress condition

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    Vahel J. A. Amedy,

    2011-07-01

    Full Text Available An experiment was conducted to evaluate the efficacy of supplemental ascorbic acid (Vitamin C on the haemagglutination inhibition (HI and enzyme linked immune sorbent assay (ELISA antibody titer of the commercial broiler chicks vaccinated against Newcastle disease (ND virus, reared under heat stress condition. A total of 420, one day-old broiler chicks were randomly divided into 4 groups and kept under elevated summer temperature and treated with four levels of added ascorbic acid i.e., 0 (control group, 200, 400, 600 mg/kg in diets for 28 days, from 21 to 49 days of experimental period. HI antibody titer and ELISA antibody titer against ND virus were significantly (P<0.05 higher at 600 mg/kg Vitamin C in the diet than the others treatments. Apparently, adding ascorbic acid at 600 mg/kg in the diet could improve humoral immunity in broilers reared under heat stress.

  15. A novel method for the determination of ascorbic acid and antioxidant capacity in Opuntia ficus indica using in vivo microdialysis.

    Science.gov (United States)

    Pretti, L; Bazzu, G; Serra, P A; Nieddu, G

    2014-03-15

    A simple and rapid method was developed for in vivo simultaneous determination of ascorbic-acid and antioxidant capacity in microdialysates from cladodes of Opuntia ficus-indica (L.) Miller. The method is verified in water-stressed plants, as compared with a well-watered test controls. The microdialysis probe construction and insertion procedure was specifically developed to minimise the tissue trauma of the plant and to obtain optimal dialysis performance. Microdialysis was performed using a flow rate of 3 μL/min and the samples were analysed by HPLC coupled to electrochemical detection of ascorbic-acid and DPPH-determined antioxidant capacity. Our data indicate exponential decay of the concentrations of the analysed compounds as a function of microdialysis sampling time. Water-stressed Opuntia show decreased ascorbic acid levels and increased the others antioxidants.

  16. Calcium and ascorbic acid affect cellular structure and water mobility in apple tissue during osmotic dehydration in sucrose solutions.

    Science.gov (United States)

    Mauro, Maria A; Dellarosa, Nicolò; Tylewicz, Urszula; Tappi, Silvia; Laghi, Luca; Rocculi, Pietro; Rosa, Marco Dalla

    2016-03-15

    The effects of the addition of calcium lactate and ascorbic acid to sucrose osmotic solutions on cell viability and microstructure of apple tissue were studied. In addition, water distribution and mobility modification of the different cellular compartments were observed. Fluorescence microscopy, light microscopy and time domain nuclear magnetic resonance (TD-NMR) were respectively used to evaluate cell viability and microstructural changes during osmotic dehydration. Tissues treated in a sucrose-calcium lactate-ascorbic acid solution did not show viability. Calcium lactate had some effects on cell walls and membranes. Sucrose solution visibly preserved the protoplast viability and slightly influenced the water distribution within the apple tissue, as highlighted by TD-NMR, which showed higher proton intensity in the vacuoles and lower intensity in cytoplasm-free spaces compared to other treatments. The presence of ascorbic acid enhanced calcium impregnation, which was associated with permeability changes of the cellular wall and membranes.

  17. Effect of Ocimum sanctum, ascorbic acid, and verapamil on macrophage function and oxidative stress in mice exposed to cocaine

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    Bhattacharya S

    2009-01-01

    Full Text Available Objective: To investigate the effect of Ocimum sanctum, ascorbic acid, and verapamil on macrophage function and oxidative stress in experimental animals exposed to cocaine. Materials and Methods: Mice were used in this study and were divided randomly into different groups of six animals each. They were either treated with intraperitoneal injection of saline or cocaine hydrochloride or an oral feeding of oil of Ocimum sanctum, ascorbic acid or verapamil, or both (ascorbic acid and verapamil, and were evaluated for a respiratory burst of macrophages, superoxide and nitric oxide (NO production, estimation of TNF-a in the serum and supernatant of cultured macrophages, estimation of lipid peroxidation (malondialdehyde- MDA in the serum, and superoxide dismutase activity in the erythrocytes. Results: Unstimulated respiratory burst as well as superoxide production was enhanced on treatment with cocaine and all the three drugs were found to attenuate this enhancement. The bactericidal capacity of macrophages decreased significantly on chronic cocaine exposure, as it was associated with decreased respiratory burst and superoxide production. There was a significant decrease in NO production by macrophages on chronic cocaine exposure and all the test drugs were found to restore nitrite formation to a normal level. There was an increase in the malonylodialdehyde (MDA level and decrease in the superoxide dismutase level on chronic cocaine exposure, and all the three drugs effectively decreased the MDA level and increased superoxide dismutase level. There was an increase in serum TNF-α on chronic cocaine exposure, which was decreased significantly by ascorbic acid and verapamil. Conclusion: O. sanctum, ascorbic acid, and verapamil were equally effective in improving the macrophage function and reducing oxidative stress. These findings suggested that O. sanctum, ascorbic acid, and verapamil attenuated acute and chronic cocaine-mediated effects.

  18. Nitrogen dioxide reducing ascorbic acid technologies in the ventilator circuit leads to uniform NO concentration during inspiration.

    Science.gov (United States)

    Pezone, Matthew J; Wakim, Matthew G; Denton, Ryan J; Gamero, Lucas G; Roscigno, Robert F; Gilbert, Richard J; Lovich, Mark A

    2016-08-31

    Conventional inhaled NO systems deliver NO by synchronized injection or continuous NO flow in the ventilator circuitry. Such methods can lead to variable concentrations during inspiration that may differ from desired dosing. NO concentrations in these systems are generally monitored through electrochemical methods that are too slow to capture this nuance and potential dosing error. A novel technology that reduces NO2 into NO via low-resistance ascorbic-acid cartridges just prior to inhalation has recently been described. The gas volume of these cartridges may enhance gas mixing and reduce dosing inconsistency throughout inhalation. The impact of the ascorbic-acid cartridge technology on NO concentration during inspiration was characterized through rapid chemiluminescence detection during volume control ventilation, pressure control ventilation, synchronized intermittent mandatory ventilation and continuous positive airway pressure using an in vitro lung model configured to simulate the complete uptake of NO. Two ascorbic acid cartridges in series provided uniform and consistent dosing during inspiration during all modes of ventilation. The use of one cartridge showed variable inspiratory concentration of NO at the largest tidal volumes, whereas the use of no ascorbic acid cartridge led to highly inconsistent NO inspiratory waveforms. The use of ascorbic acid cartridges also decreased breath-to-breath variation in SIMV and CPAP ventilation. The ascorbic-acid cartridges, which are designed to convert NO2 (either as substrate or resulting from NO oxidation during injection) into NO, also provide the benefit of minimizing the variation of inhaled NO concentration during inspiration. It is expected that the implementation of this method will lead to more consistent and predictable dosing.

  19. Effect of different ascorbic acid levels (Vitamin C on eco-physiological properties of barley in soils contaminated with lead

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    Kamdin Akhavan Samimi

    2016-03-01

    Full Text Available This study was carried out to examine the effects of foliar application of ascorbic acid on barley in contaminated soil in a completely randomized factorial design with 2 factors, 9 treatments and 3 replications in Varamin in 1393.150 mg of lead nitrate per kg of soil were applied to infect the soil for all treatments. Superabsorbent was the first factor used in three levels (0, 3, 6 g per kg soil and ascorbic acid as the second factor was also used in three levels (0, 50 and 100 ppm. The results of this experiment showed that increase in superabsorbent and ascorbic acid concentrations in barley improved the morphological traits such as plant height and spike and grain number, grain weight, total weight of shoot, root dry weight and thousand grain weight and also improved physiological traits such as protein content and chlorophyll a, b and total chlorophyll in barley, moreover, increase in ascorbic acid in the plant resulted in reduction in antioxidant enzymes content such as superoxide dismutase andcatalase, and physiological traits such as proline, increased relative water content and reduced lead content in leaves and roots.So it can be concluded that, given that the country is located in arid and semiarid regions and considering Iran’s soils pollution with heavy metals,using effective treatments such as ascorbic acid can enhance crop water holding capacity and also reduce the effects of these elements toxicity. Therefore,the use of ascorbic acid seems essential.Due to the non-degradable and long life of heavy metals in soil, insoluble hydrophilic polymers with different amounts carboxylic groups are used. The surface carboxylic groups of the polymer (SAP due to exposure to pH are ionized and make strong bonds with soil pollutant metals, and eventually form a gel and are separated from soil.

  20. "Oral ascorbic acid in combination with beta blockers in prevention of atrial fibrillation after Coronary Artery Bypass Graft "

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    Mousavi M

    2007-04-01

    Full Text Available Background: Adrenergic beta antagonists are not sufficient to prevent atrial fibrillation after coronary artery bypass graft (CABG. This study was designed to evaluate the effect of ascorbic acid as an adjunct to beta-blockers in prevention of post-CABG atrial fibrillation Methods: Patients who were more than 50 years old and scheduled to undergo CABG were included if they were treated with beta-blockers at least 1 week before surgery. Patients with previous history of atrial fibrillation, AV block, heart rate <50 /min, end-stage renal disease, severe pulmonary or liver disease and those who were taking digoxin or class I and III anti-arrhythmics or had pacemakers were not included. Ascorbic acid group were prescribed 2 gm of ascorbic acid, the night before the surgery, and 1 gm twice daily for 5 days after surgery. Beta blockers continued in both group after surgery. Telemetry monitoring was performed in ICU and Holter monitoring was performed for 4 days. Results: Fifty patients completed the study as ascorbic acid and 50 as control group. The population was 60.19 ± 7.14 years old and 67% were male. The incidence of postoperative atrial fibrillation was 4% in the ascorbic acid group and 26% in control group (odds ratio=0.119, 95% confidence interval: 0.025 to 0.558, P=0.002 Conclusion: Ascorbic acid is well-tolerated, relatively safe and seems effective. Therefore it can be prescribed as an adjunct to beta-blockers for prophylaxis of post-CABG atrial fibrillation.

  1. Determining Total Phenolics, Anthocyanin Content and Ascorbic Acid Content in Some Plum Genotypes Grown in Ardahan Ecological Conditions

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    Z. T. ABACI

    2014-06-01

    Full Text Available In this study, total phenol content, total anthocyanin content, brix, pH, titrable acidity and total ascorbic acid content in the five plum genotypes cultivated in Ardahan City are determined and sustenance of the plums are revealed. Total phenol content was determined with folin-ciocalteu’s method, total anthocyanin content was determined with pH differential method and total ascorbic acid was determined with 2,6-dichlorophenolindophenol method.It is detected that the genotype with the highest brix content (%13.9 and lowest acidity (%0.98 is cancur, the genotype with the lowest brix content (%11 and highest acidity (%2.06 is wild plum, the genotype with the highest content of total anthocyanin, total phenolic substance and ascorbic acid is the wild plum and the genotype with the least content of these is the water plum. As a result of the study, it is revealed that the plum fruit has high levels of phenolic substance, anthocyanin and ascorbic acid content, so it has a high sustenance.

  2. Effects of humic acids, para-aminobenzoic acid and ascorbic acid on the N-nitrosation of the carbamate insecticide propoxur and on the mutagenicity of nitrosopropoxur.

    Science.gov (United States)

    Gichner, T; Badaev, S A; Pospísil, F; Velemínský, J

    1990-03-01

    Nitrosation of the carbamate insecticide propoxur at pH 3 and 37 degrees C was determined colorimetrically and found to be time- and sodium nitrite concentration-dependent. Nitrosated propoxur was mutagenic when exposed to the seeds of the higher plant Arabidopsis thaliana but the formation of nitrosopropoxur, the presumed mutagen, was inhibited by humic acids, para-aminobenzoic acid and ascorbic acid. These agents also reduced the mutagenicity of preformed nitrosopropoxur.

  3. l-dehydroascorbic acid can substitute l-ascorbic acid as dietary vitamin C source in guinea pigs

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    Henriette Frikke-Schmidt

    2016-04-01

    Full Text Available Vitamin C deficiency globally affects several hundred million people and has been associated with increased morbidity and mortality in numerous studies. In this study, bioavailability of the oxidized form of vitamin C (l-dehydroascorbic acid or DHA—commonly found in vitamin C containing food products prone to oxidation—was studied. Our aim was to compare tissue accumulation of vitamin C in guinea pigs receiving different oral doses of either ascorbate or DHA. In all tissues tested (plasma, liver, spleen, lung, adrenal glands, kidney, muscle, heart, and brain, only sporadic differences in vitamin C accumulation from ascorbate or DHA were observed except for the lowest dose of DHA (0.25 mg/ml in the drinking water, where approximately half of the tissues had slightly yet significantly less vitamin C accumulation than from the ascorbate source. As these results contradicted data from rats, we continued to explore the ability to recycle DHA in blood, liver and intestine in guinea pigs, rats and mice. These investigations revealed that guinea pigs have similar recycling capacity in red blood cells as observed in humans, while rats and mice do not have near the same ability to reduce DHA in erythrocytes. In liver and intestinal homogenates, guinea pigs also showed a significantly higher ability to recycle DHA compared to rats and mice. These data demonstrate that DHA in guinea pigs—as in humans—is almost as effective as ascorbate as vitamin C source when it comes to taking up and storing vitamin C and further suggest that the guinea pig is superior to other rodents in modeling human vitamin C homeostasis.

  4. L-dehydroascorbic acid can substitute l-ascorbic acid as dietary vitamin C source in guinea pigs.

    Science.gov (United States)

    Frikke-Schmidt, Henriette; Tveden-Nyborg, Pernille; Lykkesfeldt, Jens

    2016-04-01

    Vitamin C deficiency globally affects several hundred million people and has been associated with increased morbidity and mortality in numerous studies. In this study, bioavailability of the oxidized form of vitamin C (l-dehydroascorbic acid or DHA)-commonly found in vitamin C containing food products prone to oxidation-was studied. Our aim was to compare tissue accumulation of vitamin C in guinea pigs receiving different oral doses of either ascorbate or DHA. In all tissues tested (plasma, liver, spleen, lung, adrenal glands, kidney, muscle, heart, and brain), only sporadic differences in vitamin C accumulation from ascorbate or DHA were observed except for the lowest dose of DHA (0.25mg/ml in the drinking water), where approximately half of the tissues had slightly yet significantly less vitamin C accumulation than from the ascorbate source. As these results contradicted data from rats, we continued to explore the ability to recycle DHA in blood, liver and intestine in guinea pigs, rats and mice. These investigations revealed that guinea pigs have similar recycling capacity in red blood cells as observed in humans, while rats and mice do not have near the same ability to reduce DHA in erythrocytes. In liver and intestinal homogenates, guinea pigs also showed a significantly higher ability to recycle DHA compared to rats and mice. These data demonstrate that DHA in guinea pigs-as in humans-is almost as effective as ascorbate as vitamin C source when it comes to taking up and storing vitamin C and further suggest that the guinea pig is superior to other rodents in modeling human vitamin C homeostasis.

  5. Functionalization of conducting polymer with novel Co(II) complex: Electroanalysis of ascorbic acid

    Energy Technology Data Exchange (ETDEWEB)

    Mohan, Swati [School of Materials Science and Technology, Institute of Technology, Banaras Hindu University, Varanasi 221005 (India); Prakash, Rajiv, E-mail: rajivprakash12@yahoo.com [School of Materials Science and Technology, Institute of Technology, Banaras Hindu University, Varanasi 221005 (India)

    2010-06-15

    We report for the first time the functionalization of a conducting polymer with a metal complex in order to develop a new type of catalytic material exhibiting better electronic communication through their delocalized {pi} electrons. The Co(II) complex having hydroxyl group as functional moiety is chemically coupled with carboxyl group of polyanthranilic acid which itself is a self doped conducting polymer. The covalent linkage between Co(II) and -OH group is confirmed using UV-vis, FT-IR and NMR spectroscopic techniques. The Co(II) complex functionalized polymer does exhibit excellent redox behavior and stability with mixed properties of Co(II) complex and {pi}-conjugated polymer. The material possesses potential benefits in sensors/biosensor applications and it is demonstrated for the electroanalysis of ascorbic acid at a level of nano molar concentration.

  6. The use of L-ascorbic acid in speciation of arsenic compounds in drinking water

    Directory of Open Access Journals (Sweden)

    Marjanović Nikola J.

    2009-01-01

    Full Text Available Arsenic speciation, besides total arsenic content determination, is very important in analysis of water, foodstuffs, and environmental samples, because of varying degrees of toxicity of different species. For such purpose hydride generation atomic absorption spectrometry can be used based on the generation of certain types of hydride, depending on the pH value and pretreatment in different reaction media. In this study, we have investigated the effect of L-ascorbic acid as the reaction medium as well as the pre-reducing agent in speciation of arsenic by hydride generation-atomic absorption spectrometry in order to determine monomethyl arsonic acid (MMA in the presence of inorganic forms of arsenic.

  7. [Content of biologically active substances--selenium, flavonoids, ascorbic acid and chlorophyllin of Allium ursinum L and Allium victorialis L].

    Science.gov (United States)

    Golubkina, N A; Malankina, E L; Kosheleva, O V; Solov'eva, A I

    2010-01-01

    Accumulation of selenium, flavonoids, chlorophyll and vitamin C by Allium ursinum L. and Allium victorialis L. are studied. Allium victorialis L. is shown to accumulate twice more selenium and flavonoids compared to Allium ursinum L. Increase of insolation elevates the concentration of the element, flavonoids and ascorbic acid in plants. Selenium concentration in Allium victorialis L. after selenium fertilization is higher compared to Allium ursinum L. The results indicate the significance of Allium victorialis L. as a source of natural antioxidants: selenium, flavonoids and ascorbic acid.

  8. Combined treatment with vitamin B12b and ascorbic acid causes in vitro DNA degradation in tumor cells.

    Science.gov (United States)

    Medvedev, A I; Akatov, V S; Kreshchenko, N D; Solov'eva, M E; Leshchenko, V V; Lezhnev, E I; Yakubovskaya, R I

    2001-04-01

    Incubation of Ehrlich ascites carcinoma and HEp-2 human epidermoid laryngeal carcinoma cells with hydroxycobalamin (vitamin B12b) and ascorbic acid induced generation and accumulation of double-stranded DNA fragments (23,000 b.p. and longer) in cells. The same vitamins alone in the same concentrations produced no such effects. DNA degradation in HEp-2 cells caused by long-term (4 h) incubation with 5-25 microM hydroxycobalamin and ascorbic acid (1:10-1:40 molar ratio) at 37 degrees C was comparable with that induced by gamma-irradiation in a dose of 150 Gy at 4 degrees C.

  9. Dye-sensitized photopolymerization of N,N -methylenebisacrylamide by initiation with eosin-ascorbic acid system

    Indian Academy of Sciences (India)

    Parthasarathy Tigulla; Uma Vuruputuri

    2004-03-01

    The dye-sensitized photopolymerization of N,N'-methylenebisacrylamide (MBA) in aqueous medium initiated by eosin-ascorbic acid (AH2) was studied at 25°C. The polymerization takes place only at higher concentration of AH2 (> 10-3 mol/L) and its rate increases rapidly as [AH2] is increased. The rate of polymerization is proportional to [MBA] and [AH2]. Kinetic results indicate that semi-quinone (DH) dye radical and semi-oxidized form () of ascorbic acid are unable to initiate polymerization. Formation of H2O2 is proposed and confirmed. A suitable mechanism is proposed in accordance with experimental results obtained.

  10. ROLE OF ASCORBIC ACID ON GERMINATION INDEXES AND ENZYME ACTIVITY OF VICIA FABA SEEDS GROWN UNDER SALINITY STRESS

    OpenAIRE

    Awatif A. Mohsen; Mohsen K. H. Ebrahim; Wael F. S. Ghoraba

    2014-01-01

    The present work aimed to investigate changes in growth and some metabolic activities in NaCl-stressed bean seedlings, and assessing the role of ascorbic acid to alleviate these changes. The germination was carried out to study the response of presoaked faba bean seeds (Vicia faba cv. Misr 2) in freshly prepared ascorbic acid (50 ppm ≈ 0.3 mM; as recommended dose as described by El-Tayeb, 1995) or distilled water (control) for 4 hrs at natural environmental conditions, to salinity stress duri...

  11. Furan Occurrence in Starchy Food Model Systems Processed at High Temperatures: Effect of Ascorbic Acid and Heating Conditions

    DEFF Research Database (Denmark)

    Mariotti, María; Granby, Kit; Fromberg, Arvid

    2012-01-01

    Furan, a potential carcinogen, has been detected in highly consumed starchy foods, such as bread and snacks; however, research on furan generation in these food matrixes has not been undertaken, thus far. The present study explored the effect of ascorbic acid addition and cooking methods (frying...... and baking) over furan occurrence and its relation with the non-enzymatic browning in a wheat flour starchy food model system. Results showed that furan generation significantly increased in the presence of ascorbic acid after 7 min of heating (p

  12. Regulation of ascorbic acid and of xylulose synthesis in liver extracts. The effect of starvation in various animals

    Science.gov (United States)

    Stirpe, F.; Comporti, M.; Della Corte, E.

    1965-01-01

    1. The effect of starvation on the synthesis of ascorbic acid and of xylulose from glucuronolactone and from gulonate has been studied with liver extracts from cats, rabbits, hamsters, mice and guinea pigs. 2. The synthesis of ascorbic acid from glucuronolactone is decreased in all species except cats, and that from gulonate is decreased in hamsters and mice only. 3. The synthesis of xylulose from glucuronolactone was decreased in all species except cats and mice, whereas from gulonate it was enhanced in all the species examined. PMID:14340085

  13. Effect of Thermoultrasound on the Antioxidant Compounds and Fatty Acid Profile of Blackberry (Rubus fruticosus spp.) Juice.

    Science.gov (United States)

    Manríquez-Torres, José de Jesús; Sánchez-Franco, José Antonio; Ramírez-Moreno, Esther; Cruz-Cansino, Nelly Del Socorro; Ariza-Ortega, José Alberto; Torres-Valencia, Jesús Martín

    2016-11-29

    Blackberry (Rubus fruticosus spp.) fruit has high antioxidant activity due to its significant content of anthocyanins and antioxidant compounds. Among emerging technologies for food preservation, thermoultrasound is a technique that reduces microbial loads and releases compounds with antioxidant properties. The objective of this study was to determine the antioxidant content and fatty acid profile of blackberry juice subjected to thermoultrasound treatment in comparison to pasteurized juice. Blackberry juice and n-hexane extracts from a control (untreated juice), pasteurized, and thermoultrasonicated samples were evaluated for antioxidant activity, fatty acid profile, and antioxidant content. The juice treated with thermoultrasound exhibited significantly (p juice also had the highest antioxidant activity (177.5 mg VCEAC/L and 1802.6 µmol TE/L). The fatty acid profile of the n-hexane extracts showed the presence of myristic, linolenic, stearic, oleic, and linoleic acids and was not affected by the treatments except for stearic acid, whose amount was particularly higher in the control. Our results demonstrated that thermoultrasound can be an alternative technology to pasteurization that maintains and releases antioxidant compounds and preserves the fatty acids of fruit juice.

  14. Effect of Thermoultrasound on the Antioxidant Compounds and Fatty Acid Profile of Blackberry (Rubus fruticosus spp. Juice

    Directory of Open Access Journals (Sweden)

    José de Jesús Manríquez-Torres

    2016-11-01

    Full Text Available Blackberry (Rubus fruticosus spp. fruit has high antioxidant activity due to its significant content of anthocyanins and antioxidant compounds. Among emerging technologies for food preservation, thermoultrasound is a technique that reduces microbial loads and releases compounds with antioxidant properties. The objective of this study was to determine the antioxidant content and fatty acid profile of blackberry juice subjected to thermoultrasound treatment in comparison to pasteurized juice. Blackberry juice and n-hexane extracts from a control (untreated juice, pasteurized, and thermoultrasonicated samples were evaluated for antioxidant activity, fatty acid profile, and antioxidant content. The juice treated with thermoultrasound exhibited significantly (p < 0.05 higher levels of total phenols (1011 mg GAE/L, anthocyanins (118 mg Cy-3-GlE/L; antioxidant activity by ABTS (44 mg VCEAC/L and DPPH (2665 µmol TE/L in comparison to the control and pasteurized samples. Oil extract from thermoultrasound juice also had the highest antioxidant activity (177.5 mg VCEAC/L and 1802.6 µmol TE/L. The fatty acid profile of the n-hexane extracts showed the presence of myristic, linolenic, stearic, oleic, and linoleic acids and was not affected by the treatments except for stearic acid, whose amount was particularly higher in the control. Our results demonstrated that thermoultrasound can be an alternative technology to pasteurization that maintains and releases antioxidant compounds and preserves the fatty acids of fruit juice.

  15. The protective role of ascorbic acid on hippocampal CA1 pyramidal neurons in a rat model of maternal lead exposure.

    Science.gov (United States)

    Sepehri, Hamid; Ganji, Farzaneh

    2016-07-01

    Oxidative stress is a major pathogenic mechanism of lead neurotoxicity. The antioxidant ascorbic acid protects hippocampal pyramidal neurons against cell death during congenital lead exposure; however, critical functions like synaptic transmission, integration, and plasticity depend on preservation of dendritic and somal morphology. This study was designed to examine if ascorbic acid also protects neuronal morphology during developmental lead exposure. Timed pregnant rats were divided into four treatment groups: (1) control, (2) 100mg/kg ascorbic acid once a day via gavage, (3) 0.05% lead acetate in drinking water, and (4) 0.05% lead+100mg/kg oral ascorbic acid. Brains of eight male pups (P25) per treatment group were processed for Golgi staining. Changes in hippocampal CA1 pyramidal neurons' somal size were estimated by cross-sectional area and changes in dendritic arborization by Sholl's analysis. One-way ANOVA was used to compare results among treatment groups. Lead-exposed pups exhibited a significant decrease in somal size compared to controls (Pascorbic acid. Sholl's analysis revealed a significant increase in apical dendritic branch points near cell body (PAscorbic acid significantly but only partially reversed the somal and dendritic damage caused by developmental lead exposure. Oxidative stress thus contributes to lead neurotoxicity but other pathogenic mechanisms are also involved.

  16. Measurement of cardiac output in adult and newborn animals by ascorbic acid dilution.

    Science.gov (United States)

    Smallwood, J K; Haselby, K A; Paradise, R R

    1984-05-01

    We have developed an ascorbic acid-dilution method for measuring cardiac output which requires minimal blood withdrawal. Ascorbate is injected into a central venous catheter. The indicator-dilution curve is obtained by drawing blood from an arterial catheter through an amperometric cell at 0.96 ml/min for 35 s. The current is measured by a picoammeter . A calibration curve is obtained in 15 s prior to each indicator-dilution curve. An on-line digital computer measures the curve areas and calculates the cardiac output. Cardiac outputs of heparinized dogs anesthetized with pentobarbital and halothane measured by this method (AA) compared closely to cardiac outputs measured by the dye-dilution method (CG) (AA = 0.96 CG + 20 ml/min, r = 0.98). Both the cardiac output and the arterial blood pressure remained stable during replicate measurements of the cardiac output of 1-day-old piglets. This system allows cardiac output determinations of neonatal subjects without excessive blood removal and, with further development, should be practical in human neonates.

  17. Effects of ozone on apoplast/cytoplasm partitioning of ascorbic acid in snap bean

    Energy Technology Data Exchange (ETDEWEB)

    Burkey, K.O. [North Carolina State Univ., Dept. of Crop Science and Botany, Raleigh, NC (United States)

    1999-07-01

    Apoplast/cytoplasm partitioning of ascorbic acid (AA) was examined in four genotypes of snap bean (Phaseolus vulgaris L.) known to differ in ozone sensitivity. Plants were grown in pots under field conditions using open-top chambers to establish charcoal-filtered (CF) air (36 nmol mol{sup -1} ozone) or elevated ozone (77 nmol mol{sup -1} ozone) treatments, AA in fully expanded leaves of 36-day-old plants was separated into apoplast and cytoplasm fractions by vacuum infiltration methods using glucose 6-phosphate as a marker for cytoplasm contamination, Apoplast ascorbate levels ranged from 30 to 150 nmol g{sup -1} fresh weight. Ozone-sensitive genotypes partitioned 1-2% of total AA into the apoplast under CF conditions and up to 7% following a 7-day ozone exposure. In contrast, an ozone-tolerant genotype partitioned 3-4% of total leaf AA into the leaf apoplast in both CF and ozone-treated plants. The results suggest that genetic background and ozone stress are factors that affect AA levels in the extracellular space. For all genotypes, the fraction of AA in the oxidized form was higher in the apoplast compared to the cytoplasm, indicative of a more oxidizing environment within the cell wall. (au)

  18. Extinction of Vibrio cholerae in acidic substrata: contaminated cabbage and lettuce treated with lime juice.

    Science.gov (United States)

    Mata, L; Vargas, C; Saborío, D; Vives, M

    1994-12-01

    Lime juice killed millions of Vibrio cholerae O1, El Tor, Inaba, present on cabbage and lettuce contaminated in the laboratory. The lethal effect was evident within 5 min of exposure to lime juice. No vibrios could be recovered at dilution 1:10 using alkaline peptone water (APW) and thiosulfate-citrate-bile salts-saccharose agar (TCBS). More than 99.9% of the initial inoculum was effectively destroyed. The number of vibrios killed by lime juice was 2 to 6 logarithms greater than the maximum infecting dose, and 4 to 8 logs greater than the minimum infecting dose for cholera El Tor. The time interval needed for killing was smaller than the usual waiting time for serving food in homes and restaurants. The addition of lime juice to non-acidic foods, beverages and water, is strongly recommended to prevent infection with cholera vibrios and other acid-sensitive microorganisms. This measure is particularly important for rural and slum populations in the tropics and subtropics.

  19. Ascorbate recycling in human neutrophils: Induction by bacteria

    OpenAIRE

    Wang, Yaohui; Russo, Thomas A.; Kwon, Oran; Chanock, Stephen; Rumsey, Steven C.; Levine, Mark

    1997-01-01

    Ascorbate (vitamin C) recycling occurs when extracellular ascorbate is oxidized, transported as dehydroascorbic acid, and reduced intracellularly to ascorbate. We investigated microorganism induction of ascorbate recycling in human neutrophils and in microorganisms themselves. Ascorbate recycling was determined by measuring intracellular ascorbate accumulation. Ascorbate recycling in neutrophils was induced by both Gram-positive and Gram-negative pathogenic bacteria, and the fungal pathogen C...

  20. Contributions of phenolics and added vitamin C to the antioxidant capacity of pomegranate and grape juices: synergism and antagonism among constituents†

    OpenAIRE

    Bolling, Bradley W.; Chen, Ya-Yen; Chen, C-Y. Oliver

    2013-01-01

    The aim of this study was to examine the contribution of sugar, organic acid, neutral phenol, and anthocyanin fractions and added ascorbic acid to grape and pomegranate-nectarine juice total phenol, ORAC, FRAP, and DPPH values. Neutral phenol and anthocyanin fractions contributed ≥75% of the total antioxidant capacity (TAC) for both juices. Intrinsic synergy and antagonism among the fractionated constituents occurred inconsistently in each assay. Sugars and organic acids antagonized pomegrana...

  1. Separative determination of ascorbic acid analogs contained in mushrooms by high-performance liquid chromatography.

    Science.gov (United States)

    Okamura, M

    1998-02-01

    Analogs (6-deoxyascorbic acid, erythroascorbic acid, and associated glycosides) of L-ascorbic acid (AA) contained in mushrooms were allowed to react with hydrazine to form osazones, and the conditions for separative determination by HPLC using a Zorbax SIL column were examined. Separation was started using solvent system 1 (ethylacetate/n-hexane/acetone/acetic acid, 50:50:1:1, v/v) as the mobile phase, and switching after 15 min to solvent system 2 (ethylacetate/acetone/acetic acid, 100:1:1, v/v). Detection was performed by absorbance at 500 nm. Because these analogs showed different formation rates for osazone, calibration curves were prepared for each substance. The recovery rate in the load test was 93-105%. By this method, AA and the analogs contained in eight species of edible mushrooms have been determined. The results revealed that: (1) the main constituents of all mushrooms are AA analogs rather than AA itself; (2) only one species contained AA in a very small amount (2 mumol/kg); (3) the types of AA analogs present differed according to the species of mushrooms, and (4) the total amount of AA analogs was between ca. 100-500 mumol/kg (2-9 mg per 100 g, converted to AA). In addition, a new AA analog was found in Pleurotus ostreatus and identified as 5-O-(alpha-D-xylopyranosyl)-D-erythroascorbic acid in structural analyses by NMR and other methods.

  2. Use of autochthonous lactic acid bacteria starters to ferment mango juice for promoting its probiotic roles.

    Science.gov (United States)

    Liao, Xue-Yi; Guo, Li-Qiong; Ye, Zhi-Wei; Qiu, Ling-Yan; Gu, Feng-Wei; Lin, Jun-Fang

    2016-05-18

    Strains of Leuconostoc mesenteroides, Pediococcus pentosaceus, and Lactobacillus brevis were identified from mango fruits by partial 16S rDNA gene sequence. Based on the ability of producing mannitol and diacetyl, Leuconostoc mesenteroides MPL18 and MPL39 were selected within the lactic acid bacteria isolates, and used as mixed starters to ferment mango juice (MJ). Both the autochthonous strains grew well in fermented mango juice (FMJ) and remained viable at 9.81 log cfu mL(-1) during 30 days of storage at 4°C. The content of total sugar of FMJ was lower than that of MJ, while the concentration of mannitol was higher than that of MJ, and the concentration of diacetyl was 3.29 ± 0.12 mg L(-1). Among detected organic acids including citric acid, gallic acid, lactic acid, and acetic acid, only citric acid and gallic acid were found in MJ, while all detected organic acids were found in FMJ. The concentration of lactic acid of FMJ was the highest (78.62 ± 13.66 mM) among all detected organic acids. The DPPH radical scavenging capacity of FMJ was higher than that of MJ. Total phenolic compounds were better preserved in FMJ. The acidity and sweetness had a noticeable impact on the overall acceptance of the treated sample.

  3. Bioactive and functional properties of sour cherry juice (Prunus cerasus).

    Science.gov (United States)

    Cásedas, Guillermo; Les, Francisco; Gómez-Serranillos, Maria Pilar; Smith, Carine; López, Víctor

    2016-11-09

    Sour cherry juice (Prunus cerasus) is consumed as a nutritional supplement claiming health effects. The aim of the study was to evaluate the different properties of sour cherry juice in terms of antioxidant activity and inhibition of target enzymes in the central nervous system and diabetes. The content of polyphenols and anthocyanins was quantified. Different experiments were carried out to determine the radical scavenging properties of the juice. The activity of sour cherry juice was also tested in physiological relevant enzymes of the central nervous system (acetylcholinesterase, monoamine oxidase A, tyrosinase) and others involved in type 2 diabetes (α-glucosidase, dipeptidyl peptidase-4). Sour cherry juice showed significant antioxidant effects but the activity of the lyophilized juice was not superior to compounds such as ascorbic, gallic or chlorogenic acid. Furthermore, sour cherry juice and one of its main polyphenols known as chlorogenic acid were also able to inhibit monoamine oxidase A and tyrosinase as well as enzymes involved in diabetes. This is the first time that sour cherry juice is reported to inhibit monoamine oxidase A, α-glucosidase and dipeptidyl peptidase-4 in a dose dependent manner, which may be of interest for human health and the prevention of certain diseases.

  4. Oral high dose ascorbic acid treatment for one year in young CMT1A patients: a randomised, double-blind, placebo-controlled phase II trial

    NARCIS (Netherlands)

    Verhamme, C.; de Haan, R.J.; Vermeulen, M.; Baas, F.; de Visser, M.; van Schaik, I.N.

    2009-01-01

    ABSTRACT: BACKGROUND: High dose oral ascorbic acid substantially improved myelination and locomotor function in a Charcot-Marie-Tooth type 1A mouse model. A phase II study was warranted to investigate whether high dose ascorbic acid also has such a substantial effect on myelination in Charcot-Marie-

  5. Ascorbic acid-dependent gene expression in Streptococcus pneumoniae and the activator function of the transcriptional regulator UlaR2

    NARCIS (Netherlands)

    Afzal, Muhammad; Shafeeq, Sulman; Kuipers, Oscar P

    2015-01-01

    In this study, we have explored the impact of ascorbic acid on the transcriptome of Streptococcus pneumoniae D39. The expression of several genes and operons, including the ula operon (which has been previously shown to be involved in ascorbic acid utilization), the AdcR regulon (which has been prev

  6. Alteration of chemical behavior of L-ascorbic acid in combination with nickel sulfate at different pH solutions in vitro

    Institute of Scientific and Technical Information of China (English)

    Shaheen A Maniyar; Jameel G Jargar; Swastika N Das; Salim A Dhundasi; Kusal K Das

    2012-01-01

    Objective: To evaluate the alteration of chemical behavior of L-ascorbic acid (vitamin C) with metal ion (nickel) at different pH solutions in vitro. Methods: Spectra of pure aqueous solution of L-ascorbic acid (E mark) compound and NiSO4 (H2O) (sigma USA) were evaluated by UV visible spectrophotometer. Spectral analysis of L-ascorbic acid and nickel at various pH (2.0, 7.0, 7.4 and 8.6) at room temperature of 29℃ was recorded. In this special analysis, combined solution of L-ascorbic acid and nickel sulfate at different pH was also recorded. Results: The result revealed that λmax (peak wavelength of spectra) of L-ascorbic acid at pH 2.0 was 289.0 nm whereas at neutral pH 7.0, λmax was 295.4 nm. In alkaline pH 8.6, λmax was 295.4 nm and at pH 7.4 the λmax of L-ascorbic acid remained the same as 295.4 nm. Nickel solution at acidic pH 2.0 was 394.5 nm, whereas at neutral pH 7.0 and pH 7.4 were the same as 394.5 nm. But at alkaline pH 8.6, λmax value of nickel sulfate became 392.0 nm. The combined solution of L-ascorbic acid and nickel sulfate (6 mg/mL each) at pH 2.0 showed 292.5 nm and 392.5 nm, respectively whereas at pH 7.0, L-ascorbic acid showed 296.5 nm and nickel sulfate showed 391.5 nm. At pH 7.4, L-ascorbic acid showed 297.0 nm and nickel sulfate showed 394.0 nm in the combined solution whereas at pH 8.6 (alkaline) L-ascorbic acid and nickel sulfate were showing 297.0 and 393.5 nm, respectively.Conclusions:alone or in combination with nickel sulfate in vitro at different pH. Perhaps oxidation of L-ascorbic acid to L-dehydro ascorbic acid via the free radical (HSc*) generation from the reaction of H2ASc+ Ni (II) is the cause of such alteration of λmax value of L-ascorbic acid in the presence of metal Results clearly indicate an altered chemical behavior of L-ascorbic acid either nickel.

  7. Selective extraction and determination of chlorogenic acid in fruit juices using hydrophilic magnetic imprinted nanoparticles.

    Science.gov (United States)

    Hao, Yi; Gao, Ruixia; Liu, Dechun; He, Gaiyan; Tang, Yuhai; Guo, Zengjun

    2016-06-01

    In this paper, the novel hydrophilic magnetic molecularly imprinted nanoparticles were developed for selective separation and determination of chlorogenic acid in aqueous fruit juices. The polymers were prepared by using amino-functionalized magnetic nanoparticles as carriers, branched polyethyleneimine as functional monomer, and chlorogenic acid as template molecule. Branched polyethyleneimine with abundant active amino groups could react with template sufficiently, and its unique dendritic structure may amplify the number of the imprinted cavities. Meanwhile, it would improve the hydrophilicity of imprinted materials for attaining high extraction efficiency. The resulted polymers exhibit fast kinetics, high adsorption capacity, and favorable selectivity. In addition, the obtained nanoparticles were used as solid-phase extraction sorbents for selective isolation and determination of chlorogenic acid in peach, apple, and grape juices (0.92, 4.21, and 0.75 μg mL(-1), respectively).

  8. Pineapple juice and its fractions in enzymatic browning inhibition of banana [Musa (AAA group) Gros Michel].

    Science.gov (United States)

    Chaisakdanugull, Chitsuda; Theerakulkait, Chockchai; Wrolstad, Ronald E

    2007-05-16

    The effectiveness of pineapple juice in enzymatic browning inhibition was evaluated on the cut surface of banana slices. After storage of banana slices at 15 degrees C for 3 days, pineapple juice showed browning inhibition to a similar extent as 8 mM ascorbic acid but less than 4 mM sodium metabisulfite. Fractionation of pineapple juice by a solid-phase C18 cartridge revealed that the directly eluted fraction (DE fraction) inhibited banana polyphenol oxidase (PPO) about 100% when compared to the control. The DE fraction also showed more inhibitory effect than 8 mM ascorbic acid in enzymatic browning inhibition of banana puree during storage at 5 degrees C for 24 h. Further identification of the DE fraction by fractionation with ion exchange chromatography and confirmation using model systems indicated that malic acid and citric acid play an important role in the enzymatic browning inhibition of banana PPO.

  9. Fabrication and characterisation of high performance polypyrrole modified microarray sensor for ascorbic acid determination

    Energy Technology Data Exchange (ETDEWEB)

    Samseya, J. [Alagappa University, Karaikudi, Tamil Nadu (India); Srinivasan, R., E-mail: sivarunjan@gmail.com [Central Electro Chemical Research Insititute, Karaikudi, Tamil Nadu (India); Chang, Yu-Tsern; Tsao, Cheng-Wen [Department of Cosmetic Applications, Taoyuan Innovation Institute of Technology, Taiwan (China); Vasantha, V.S. [Madurai Kamaraj University, Madurai, Tamil Nadu (India)

    2013-09-02

    Graphical abstract: -- Highlights: •Gold microelectrode array (Au/MEA) with electrode of 12 μm diameter was fabricated by photolithography technique. •Subsequently, polypyrrole (Ppy) modified gold microarrays sensor (Ppy/Au/MEA) was prepared. •Ppy/Au/MEA used for ascorbic acid determination in the presence of different neurotransmitters. •The micro array exhibited wide linear range, very high sensitivity and very low LOD than the earlier reports. •It was used successfully to test ascorbic acid in different types real samples. -- Abstract: In this study, gold microelectrode array (Au/MEA) with electrode of 12 μm diameter was fabricated by photolithography technique. Subsequently, polypyrrole (Ppy) modified gold microarrays sensor (Ppy/Au/MEA) was prepared by cyclic voltammetry technique. The deposition potential range and number of cycles were optimised in order to get optimum thickness of Ppy film. Scanning Electron Microscope and Atomic Force Microscope investigations reveal that Ppy coating formed at 3 cycles is porous with thickness of 1.5 μm which exhibiting high catalytic current for ascorbic acid (AA) in square wave technique (SWV). In contrast to earlier sensors designs, these Ppy/Au/MEA sensors exhibits lower detection limit (LOD) of 10 nm towards AA at physiological conditions. It also exhibits enhanced sensitivity (2.5 mA cm{sup −2} mM{sup −1}) and long range of linear detection limit from 10 nm to 2.8 mM. In the same way, polypyrrole modified macro Au (Ppy/Au/MA) biosensor was also fabricated and its electro catalytic property towards AA was compared with that of Ppy/Au/MEA. The Ppy/Au/MA exhibits sensitivity of only 0.27 mA cm{sup −2} mM{sup −1}, LOD of 5 μM and linear range of 10 μM to 2.2 mM. Hence, our investigations indicate that the Ppy/Au/MEA could serve as highly sensitive sensor for AA than any of the earlier designs. So, the Ppy/Au/MEA electrode was utilised for determination AA in a wide variety of real samples.

  10. Shelf life of minimally processed pineapples treated with ascorbic and citric acids

    Directory of Open Access Journals (Sweden)

    Lucimara Rogéria Antoniolli

    2012-01-01

    Full Text Available The purpose of this research was to determine the shelf life of minimally processed (MP 'Pérola' pineapples treated with ascorbic acid (AA and citric acid (CA based on physical, chemical, sensorial and microbiological attributes. Slices were dipped into drinking water (control or combined solutions of AA:CA (% (1.0:0.5 and 1.0:1.0 with sodium hypochlorite (NaClO 20 mg L-1 for 30 seconds. The samples were conditioned in polyethylene terephtalate packages and stored at 4±1 °C per 13 days. The low peroxidase activity in the slices treated with antioxidant combinations was related to low pH values observed in these samples. The treatments 1.0:0.5 and 1.0:1.0 (AA:CA, % favored maintenance of the initial a* values and avoided the pulp browning. The ascorbic acid increased more than double on the 2nd day in the treated slices. By the 4th day the CO2 values suggested a higher respiratory activity in the slices treated with anti-browning compounds. The antioxidant treatments did not produce detectable residual flavors in the MP pineapple. Regardless of microbiological safety during the 13 days of cold storage, the control slices can be kept by 6 days, afterwards the color and dehydration become strong enough to affect the appearance. On the other hand, MP 'Pérola' pineapples treated with 1.0:0.5 (AA:CA, % and NaClO (20 mg L-1 can be stored for 8 days at 4±1 ºC, which represents the extension of the shelf life in 2 days. After this period the overripe odor starts to develop.

  11. Influence of dietary magnesium on mineral, ascorbic acid and glutathione concentrations in tissues of a freshwater fish, the common carp.

    Science.gov (United States)

    Dabrowska, H; Dabrowski, K

    1990-01-01

    Supplementation with dietary Mg at a minimum level of 0.06% seems to be essential to prevent the hypercalcinosis of the kidney and hepatopancreas in a fish, the common carp. Mg deficiency appears to have no effect on the Mg level in kidneys and hepatic tissue, whereas the Fe level in those tissues was significantly diminished by increasing dietary Mg supplementation up to 3.2 g.kg-1. Both hypercalcinosis and accumulation of Fe in soft tissues were more pronounced in fish offered diets high in protein (44%) compared to fish on low dietary protein (25%). The ascorbic acid in the hepatopancreas and kidney was greatly depleted in fish fed the high-protein diets, and this depletion did not correlate with the dietary Mg level nor with a high level of tissue Ca. However, the increased Ca concentration in the kidney coincided with the greatest depletion of ascorbate in fish fed a high-protein diet. The concentration of ascorbate in the brain was much less affected by a low level of vitamin C in the diets than in other tissues. Depletion of ascorbate in soft tissues did not correspond to fish growth but might be rather related to the metabolic rate imposed by the dietary nutrients. It is suggested that the Mg and ascorbic acid requirements in the carp are considerably elevated by the increased dietary protein level.

  12. Acetylsalicylic acid and ascorbic acid combination improves cognition; via antioxidant effect or increased expression of NMDARs and nAChRs?

    Science.gov (United States)

    Kara, Yusuf; Doguc, Duygu Kumbul; Kulac, Esin; Gultekin, Fatih

    2014-05-01

    Chronic inflammation occurs systematically in the central nervous system during ageing, it has been shown that neuroinflammation plays an important role in the pathogenesis of many neurodegenerative disorders. Aspirin, a nonselective COX inhibitor, as well as ascorbic acid, has been purported to protect cerebral tissue. We investigated the effects of subchronic aspirin and ascorbic acid usage on spatial learning, oxidative stress and expressions of NR2A, NR2B, nAChRα7, α4 and β2. Forty male rats (16-18 months) were divided into 4 groups, namely, control, aspirin-treated, ascorbic acid-treated, aspirin+ascorbic acid-treated groups. Following 10-weeks administration period, rats were trained and tested in the Morris water maze. 8-Hydroxy-2-deoxyguanosine and malondialdehyde were evaluated by ELISA and HPLC, respectively. Receptor expressions were assessed by western blotting of hippocampi. Spatial learning performance improved partially in the aspirin group, but significant improvement was seen in the aspirin+ascorbic acid group (p acid group as compared to the control group (p acid in aged rats was shown to enhance cognitive performance and increase the expressions of several receptors related to learning and memory process.

  13. Influence of ascorbic acid on iron absorption from an iron-fortified, chocolate-flavored milk drink in Jamaican children.

    Science.gov (United States)

    Davidsson, L; Walczyk, T; Morris, A; Hurrell, R F

    1998-05-01

    The influence of ascorbic acid on iron absorption from an iron-fortified, chocolate-flavored milk drink (6.3 mg total Fe per serving) was evaluated with a stable-isotope technique in 20 6-7-y-old Jamaican children. Each child received two test meals labeled with 5.6 mg 57Fe and 3.0 mg 58Fe as ferrous sulfate on 2 consecutive days. Three different doses of ascorbic acid (0, 25, and 50 mg per 25-g serving) were evaluated in two separate studies by using a crossover design. Iron isotope ratios were measured by negative thermal ionization mass spectrometry. In the first study, iron absorption was significantly greater (P chocolate drink contained relatively high amounts of polyphenolic compounds, phytic acid, and calcium, all well-known inhibitors of iron absorption. The low iron absorption without added ascorbic acid shows that chocolate milk is a poor vehicle for iron fortification unless sufficient amounts of an iron-absorption enhancer are added. Regular consumption of iron-fortified chocolate milk drinks containing added ascorbic acid could have a positive effect on iron nutrition in population groups vulnerable to iron deficiency.

  14. Inhibition of collagen synthesis by select calcium and sodium channel blockers can be mitigated by ascorbic acid and ascorbyl palmitate.

    Science.gov (United States)

    Ivanov, Vadim; Ivanova, Svetlana; Kalinovsky, Tatiana; Niedzwiecki, Aleksandra; Rath, Matthias

    2016-01-01

    Calcium, sodium and potassium channel blockers are widely prescribed medications for a variety of health problems, most frequently for cardiac arrhythmias, hypertension, angina pectoris and other disorders. However, chronic application of channel blockers is associated with numerous side effects, including worsening cardiac pathology. For example, nifedipine, a calcium-channel blocker was found to be associated with increased mortality and increased risk for myocardial infarction. In addition to the side effects mentioned above by different channel blockers, these drugs can cause arterial wall damage, thereby contributing to vascular wall structure destabilization and promoting events facilitating rupture of plaques. Collagen synthesis is regulated by ascorbic acid, which is also essential for its optimum structure as a cofactor in lysine and proline hydroxylation, a precondition for optimum crosslinking of collagen and elastin. Therefore, the main objective in this study was to evaluate effects of various types of channel blockers on intracellular accumulation and cellular functions of ascorbate, specifically in relation to formation and extracellular deposition of major collagen types relevant for vascular function. Effects of select Na- and Ca- channel blockers on collagen synthesis and deposition were evaluated in cultured human dermal fibroblasts and aortic smooth muscle cells by immunoassay. All channel blockers tested demonstrated inhibitory effects on collagen type I deposition to the ECM by fibroblasts, each to a different degree. Ascorbic acid significantly increased collagen I ECM deposition. Nifedipine (50 µM), a representative of channel blockers tested, significantly reduced ascorbic acid and ascorbyl palmitate-dependent ECM deposition of collagen type l and collagen type lV by cultured aortic smooth muscle cells. In addition, nifedipine (50 µM) significantly reduced ascorbate-dependent collagen type l and type lV synthesis by cultured aortic smooth

  15. A direct comparison of nanosilver particles and nanosilver plates for the oxidation of ascorbic acid

    Science.gov (United States)

    Sadeghi, Babak; Meskinfam, Masoumeh

    2012-11-01

    We study of spherical silver nanoparticles of different size and Ag nanoplates were grown at zinc tin oxide (ZTO) surface and characterized using SEM. The application of different electrodes in voltammetry for determination ascorbic acid indicated that oxidation of this biomolecule occurs at these electrodes in diffusion controlled process. Ag nanoplates modified zinc tin oxide electrodes exhibit at least two to three times higher current than spherical nanosilver particles. The observed behavior suggests that Ag nanoplates exhibit higher electrocatalytic activity than spherical silver nanoparticles. The reason for such behavior may be due to lattice plane as well as due to more available surface edges. As dimensions of nanoplates are increased surface area in the case of nanoplates also appears to play a significant role.

  16. Silver nanoparticles prepared in presence of ascorbic acid and gelatin, and their electrocatalytic application

    Indian Academy of Sciences (India)

    Fereshteh Chekin; Somayeh Ghasemi

    2014-10-01

    In this paper, we reported a simple and low-cost procedure to synthesize silver nanoparticles (AgNPs) by using ascorbic acid as reducing agent and gelatin as stabilizer. The synthesized AgNPs were characterized by various means such as transmission electron microscope (TEM), powder X-ray diffraction (XRD) and energy-dispersive X-ray (EDX). TEM observations and XRD analysis demonstrated that the size of AgNPs is about 20 nm. Silver nanoparticles modified with carbon-paste electrode (AgNPs–CPE) displayed excellent electrochemical catalytic activities towards hydrogen peroxide (H2O2). The reduction overpotential of H2O2 was decreased significantly compared with those obtained at the bare CPE. The sensor responded linearly to hydrogen peroxide (H2O2) in the concentration of 10–350 M, with detection limit of 5.6 M at 3 using amperometry. The studied sensor exhibited good reproducibility and long-term stability.

  17. Simple synthesis of luminescent CdSe quantum dots from ascorbic acid and selenium dioxide.

    Science.gov (United States)

    Wang, Yilin; Yu, Meihua; Yang, Kun; Lu, Jianping; Chen, Linqing

    2015-12-01

    A simple, low-cost and convenient method was developed for the synthesis of highly luminescent CdSe quantum dots (QDs) in an aqueous medium. Compared with previous methods, this synthesis was carried out in one pot using ascorbic acid (C6H8O6) to replace NaBH4 or N2H4·H2O as a reductant, and selenium dioxide to replace selenium or its other hazardous, expensive and unstable compounds as a precursor. The mechanism of CdSe QDs formation was elucidated. The influence of various experimental variables, including refluxing time, Cd/MSA and Cd/Se molar ratios, on the luminescent properties of the QDs were systematically investigated. X-Ray powder diffraction and transmission electron microscopy characterization indicated that the QDs had a pure cubic zinc-blended structure with a spherical shape.

  18. A micro E-DNA sensor for selective detection of dopamine in presence of ascorbic acid

    Institute of Scientific and Technical Information of China (English)

    朱丹; 李敏; 王丽华; 左小磊

    2015-01-01

    In this paper, a novel method for selectively detection of dopamine (DA) in the interference of ascorbic acid (AA) is described. A nanometer-sized gold flower microelectrode (NGFME) is prepared by flame-etching and electrochemical deposition. The electrode tip was characterized by scanning electron microscope (SEM). The NGFME is sized at about 100 µm and dimensions of thorns of the electrode were in nanometers. By modifying with DA aptamer on the surface, the prepared aptasensor can selectively detect DA even in the presence of high concentration AA. Experimental results show that this NGFME has no response to AA. As a comparison, the carbon fiber electrode without DA aptamer modification is unable to effectively detect DA in the presence of AA. The NGFME is easy-to-prepare, selective and sensitive for DA detection down to 25 µM. The electrode can be expected to detect DA in vivo and in real biological samples.

  19. Rapid screening of ascorbic acid, glycoalkaloids, and phenolics in potato using high-performance liquid chromatography.

    Science.gov (United States)

    Shakya, Roshani; Navarre, Duroy A

    2006-07-26

    Evaluation of phenolic metabolism in potato tubers (Solanum tuberosum) would be facilitated by faster analytical methods. A high-throughput HPLC method was developed for the qualitative and quantitative determination in potato of numerous phenolic compounds, the sum of the glycoalkaloids chaconine and solanine, plus ascorbic acid. Following a fast extraction, HPLC run times of 12 min were achieved with the use of a monolithic RP C18 column. UV and MS analyses were used to characterize the phenolic complement in extracts from two white-fleshed varieties. Over 30 compounds were identified, some of which are thought to possess either nutritional value or are involved in plant disease resistance. This method is expected to be useful for germplasm mining and for varietal development programs in which large numbers of lines are generated.

  20. Weekly ascorbic acid infusion in castration-resistant prostate cancer patients

    DEFF Research Database (Denmark)

    Nielsen, Torben K.; Højgaard, Martin; Andersen, Jon T.

    2017-01-01

    Background: Ascorbic acid (AA) has in vivo cytotoxic properties at concentrations that can only be achieved through intravenous (IV) administration in humans. Treatment with intravenous AA is widely and increasingly used in complementary medicine despite a lack of clinical evidence for the efficacy...... of this treatment. Methods: This non-comparative, single-center, phase II trial included patients with chemotherapy-naïve, metastatic castration-resistant prostate cancer (mCRPC) from an outpatient clinic to evaluate the efficacy and safety of IV AA therapy. Patients received weekly infusions of AA (week 1, 5 g......; week 2, 30 g; and weeks 3-12, 60 g) followed by efficacy evaluation at 12 weeks. The primary endpoint for efficacy was a 50% reduction in the prostate-specific antigen (PSA) level. The secondary endpoints included changes in health-related quality of life (HRQoL), biomarkers of bone metabolism...

  1. Active biopolymer film based on carboxymethyl cellulose and ascorbic acid for food preservation

    Science.gov (United States)

    Halim, Al Luqman Abdul; Kamari, Azlan

    2017-05-01

    In the present study, an active biopolymer film based on carboxymethyl cellulose (CMC) and ascorbic acid (AA) was synthesised at an incorporation rate of 15% (w/w). Several analytical instruments such as Fourier Transform Infrared Spectrometer (FTIR), Thermogravimetry Analyser (TGA), UV-Visible Spectrophotometer (UV-Vis), Scanning Electron Microscope (SEM) and Universal Testing Machine were used to characterise the physical and chemical properties of CMC-AA film. The addition of AA significantly reduced elongation at break (322%) and tensile strength (10 MPa) of CMC-AA film. However, CMC-AA film shows a better antimicrobial property against two bacteria, namely Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) as compared to CMC film. The CMC-AA film was able to preserve cherry tomato with low weight loss and browning index. Overall, results from this study highlight the feasibility of CSAA film for food preservation.

  2. Au(III)-CTAB reduction by ascorbic acid: preparation and characterization of gold nanoparticles.

    Science.gov (United States)

    Khan, Zaheer; Singh, Taruna; Hussain, Javed Ijaz; Hashmi, Athar Adil

    2013-04-01

    Upon addition of tetrachloroauric(III) (HAuCl(4)) to a solution of cetyltrimethylammonium bromide (CTAB), a perfect transparent yellow colored and yellowish-precipitate appears within the time of mixing, indicating the formation of a complex between HAuCl(4) and CTAB. Morphology of gold nanoparticles in situ via chemical reduction of title reaction has been determined by using conventional techniques. The position and shape of the surface plasmon resonance (SRP) band strongly depends on the [ascorbic acid], [HAuCl(4)], [CTAB] and mixing ratio of the reactants. Sub-, post- and dilution-micellar effects are accountable to the aggregation and/or adsorption of gold nanoparticles onto the surface of CTAB. The morphology of particles was altered by changing the [reactants] as well as [CTAB]. A mechanism of nanoparticle formation has been proposed comprising different steps of particle growth.

  3. Manganese dioxide graphite composite electrodes: application to the electroanalysis of hydrogen peroxide, ascorbic acid and nitrite.

    Science.gov (United States)

    Langley, Cathryn E; Sljukić, Biljana; Banks, Craig E; Compton, Richard G

    2007-02-01

    The modification of carbon powder with manganese dioxide using a wet impregnation procedure with electrochemical characterisation of the modified powder is described. The process involves saturation of the carbon powder with manganese(II) nitrate followed by thermal treatment at ca. 773 K leading to formation of manganese(IV) oxide on the surface of the carbon powder. The construction of composite electrodes based on manganese dioxide modified carbon powder and epoxy resin is also described, including optimisation of the percentage of the modified carbon powder. Composite electrodes showed attractive performances for electroanalytical applications, proving to be suitable for the electrochemical detection of hydrogen peroxide, ascorbic acid and nitrite ions with limits of detection comparable to the detection limits achieved by other analytical techniques. The results obtained for detection of these analytes, together with composite electrodes flexible design and low cost offers potential application of composite electrodes in biosensors.

  4. Effect of applying modes of the polymer microneedle-roller on the permeation of L-ascorbic acid in rats.

    Science.gov (United States)

    You, Sung-Kyun; Noh, Young-Wook; Park, Hyoun-Hyang; Han, Manhee; Lee, Seung S; Shin, Sang-Chul; Cho, Cheong-Weon

    2010-01-01

    Despite the advantages of drug delivery through skin, transdermal drug delivery is only used with a small subset of drugs because most compounds cannot cross the skin at therapeutically useful rates. Recently, a new concept known as microneedle was introduced and could be used to pierce effectively to deliver drugs using micron-sized needles in a minimally invasive and painless manner. In this study, the polymer microneedle-roller was fabricated so that it can be applied into the permeation of L-ascorbic acid. Moreover, a recent publication suggested the possibility of ascorbic acid 2-phosphate as a hair restorer; hence, this study was carried out to check the effect of L-ascorbic acid itself on the hair growing rate in rats according to the presence of various application frequencies of the polymer microneedle-roller. When the polymer microneedle-roller was applied nine times with four directions into rat's shaved skin, the permeation of L-ascorbic acid increased by 10.54-fold compared to that of the absence of the polymer microneedle-roller. The histological examination revealed that the skin pretreated with various application frequencies of the polymer microneedle-roller had more transport pathways. The faster hair growing phenomenon was observed in the presence of polymer microneedle-roller compared to the absence of the polymer microneedle-roller.

  5. Amelioration of age-dependent increase in protein carbonyls of cerebral hemispheres of mice by melatonin and ascorbic acid.

    Science.gov (United States)

    Dkhar, Preeticia; Sharma, Ramesh

    2011-12-01

    Melatonin secreted by the pineal gland acts as a free radical scavenger besides its role as a hormonal signaling agent. It detoxifies a variety of free radicals and reactive oxygen intermediates including hydroxyl radical, peroxynitrite anion and singlet oxygen. Ascorbic acid (Vitamin C), a water soluble vitamin, is a naturally occurring antioxidant and cofactor in various enzymes. Protein carbonyls are formed as a consequence of the oxidative modification of proteins by reactive oxygen species. Oxidative modification alters the function of protein and is thought to play an important role in the decline of cellular functions during aging. In the present study, the effect of melatonin and ascorbic acid on age-related carbonyl content of cerebral hemispheres in mice was investigated. Protein carbonyls of cerebral hemispheres have been found to be significantly higher in 18-month-old mice as compared to 1-month old mice. Administration of a single dose of melatonin (10 mg/kg body weight) and ascorbic acid (10 mg/kg body weight) intraperitoneally for three consecutive days decreases the carbonyl content in 1- and 18-month-old mice significantly. The present study thus suggests that the formation of protein carbonyls in the cerebral hemispheres of the aging mice can be prevented by the antioxidative effects of melatonin and ascorbic acid that could in turn be beneficial in having health benefits from age-related neurodegenerative diseases.

  6. Ascorbic acid and tissue browning in pears (Pyrus communis L. cvs Rocha and Conference) under controlled atmosphere conditions

    NARCIS (Netherlands)

    Veltman, R.H.; Kho, R.M.; Schaik, van A.C.R.; Sanders, M.G.; Oosterhaven, J.

    2000-01-01

    The relationships between storage gas composition and ascorbic acid (AA) levels, and between AA levels and the development of internal browning, were studied in 'Conference' and 'Rocha' pears (Pyrus communis L.). In both cultivars, AA levels declined under (browning-inducing) controlled atmosphere (

  7. Ascorbic acid concentrations in aqueous humor after systemic vitamin C supplementation in patients with cataract: pilot study.

    Science.gov (United States)

    Hah, Young-Sool; Chung, Hye Jin; Sontakke, Sneha B; Chung, In-Young; Ju, Sunmi; Seo, Seong-Wook; Yoo, Ji-Myong; Kim, Seong-Jae

    2017-07-11

    To measure ascorbic acid concentration in aqueous humor of patients with cataract after oral or intravenous vitamin C supplementation. Forty-two eyes of 42 patients with senile cataract who underwent uncomplicated cataract surgery were enrolled. Patients (n = 14 each) were administered oral vitamin C (2 g), intravenous vitamin C (20 g) or no treatment (control group) on the day before surgery. Samples of aqueous humor (0.1 cm(3)) were obtained by anterior chamber aspiration at the beginning of surgery and stored at -80 °C. Ascorbic acid concentration in aqueous humor was measured by high-pressure liquid chromatography. The mean age at surgery was 62.5 years, with no difference among the three groups. The mean ± standard deviation concentrations of ascorbic acid in aqueous humor in the control and oral and intravenous vitamin C groups were 1347 ± 331 μmol/L, 1859 ± 408 μmol/L and 2387 ± 445 μmol/L, respectively. Ascorbic acid concentration was significantly lower in the control than in the oral (P humor is increased by systemic vitamin C supplementation, with intravenous administration being more effective than oral administration.

  8. Effect of ascorbate and 5-aminosalicylic acid on light-induced 8-hydroxydeoxyguanosine formation in V79 Chinese hamster cells

    DEFF Research Database (Denmark)

    Fischer-Nielsen, A; Loft, S; Jensen, K G

    1993-01-01

    Recently we showed that ascorbate and 5-aminosalicylic acid (5-ASA) prevented 8-hydroxydeoxyguanosine (8-OHdG) formation in calf thymus DNA exposed to UV-visible light. However, the ultimate defense against oxidative DNA damage depends on an intracellular/intranuclear effect of the compounds...

  9. Effect of high doses of L-ascorbic acid on the antioxidative/oxidative state in the rats

    DEFF Research Database (Denmark)

    Niemiec, T.; Sawosz, E.; Chwalibog, André

    2005-01-01

    The objective of this study was to determine the effects of mega-doses of vitamin C (0.3, 0.6 and 0.9% of diet) as a dietary supplement for rats on selected indices of the antioxidative/oxidative state in 40 growing Wistar rats (4x10). It was found that L-ascorbic acid and Total Antioxidative State...

  10. STABILITY OF BETACYANIN PIGMENTS FROM RED PURPLE PITAYA FRUIT (Hylocereus polyrhizus : INFLUENCE OF PH, TEMPERATURE, METAL IONS AND ASCORBIC ACID

    Directory of Open Access Journals (Sweden)

    Tang, C.S Tang, C.S

    2010-06-01

    Full Text Available Betacyanin pigments from red-purple pitaya fruit (Hylocereus polyrhizus could be an attractive source of red colourant for food application. This paper presents results on the extraction of betacyanin pigments from pitaya fruits grown locally in Malaysia. Both the flesh of the fruit and its mesocarp were investigated and it was found that the flesh had higher pigment contents compared to its peel component. The concentration of betacyanins expressed as betanin equivalents per 100 g of flesh and peel were 10.1 ± 0.6 mg and 6.7 ± 0.2 mg, respectively when 80% methanol was used.  The stability of betacyanin pigments were investigated at different pH, temperature and in presence of different concentrations of metal ions (Cu2+ and Fe2+ and ascorbic acid. The results showed that the pigment was most stable at pH range between 5 and 6. However, it forfeited its stability to the heat induced at elevated temperatures. Metal ions (Cu2+ and Fe2+ proved to be capable of accelerating betacyanin degradation, with Cu2+ exhibiting the greatest effect. By contrast, supplementation with ascorbic acid could enhance the pigment stability against the detrimental effects caused by pH, temperature and metal ions. Nevertheless, if the concentration of ascorbic acid exceeds 0.7 %, it may change its role from pigment stabilizer to become a pro-oxidant.    Keywords: Betacyanin, pigments, pitaya fruit, Hylocereus polyrhizus, ascorbic acid

  11. Hydrolytic and oxidate stability of L-(+) -ascorbic acid supported in pectin films: Influence of the macromolecular structure and calcium presence

    Science.gov (United States)

    The hydrolytic and oxidative stability of L-(+)-ascorbic acid (AA) into plasticized pectin films were separately studied in view of preserving vitamin C activity and/or to achieve localized antioxidant activity at pharmaceutical and food interfaces. Films were made with each one of the enzymatically...

  12. Ascorbic Acid-Initiated Tandem Radical Cyclization of N-Arylacrylamides to Give 3,3-Disubstituted Oxindoles

    Directory of Open Access Journals (Sweden)

    Sheng Liu

    2015-08-01

    Full Text Available An ascorbic acid-promoted and metal-free tandem room temperature cyclization of N-arylacrylamides with 4-nitrobenzenediazonium generated in situ was developed. This reaction proceeds smoothly through a radical mechanism and provides an environmentally friendly alternative approach to biologically active 3-alkyl-3-benzyloxindoles, avoiding the use of excess oxidants and light irradiation.

  13. A GREEN CHEMISTRY APPROACH TO PREPARATION OF CORE (FE OR CU)-SHELL (NOBLE METALS) NANOCOMPOSITES USING AQUEOUS ASCORBIC ACID

    Science.gov (United States)

    A greener method to fabricate novel core (Fe or Cu)-shell (noble metals) nanocomposites of transition metals such as Fe and Cu and noble metals such as Au, Pt, Pd, and Ag using aqueous ascorbic acid is described. Transition metal salts such as Cu and Fe were reduced using ascor...

  14. Phase I evaluation of intravenous ascorbic acid in combination with gemcitabine and erlotinib in patients with metastatic pancreatic cancer.

    Directory of Open Access Journals (Sweden)

    Daniel A Monti

    Full Text Available BACKGROUND: Preclinical data support further investigation of ascorbic acid in pancreatic cancer. There are currently insufficient safety data in human subjects, particularly when ascorbic acid is combined with chemotherapy. METHODS AND FINDINGS: 14 subjects with metastatic stage IV pancreatic cancer were recruited to receive an eight week cycle of intravenous ascorbic acid (three infusions per week, using a dose escalation design, along with standard treatment of gemcitabine and erlotinib. Of 14 recruited subjects enrolled, nine completed the study (three in each dosage tier. There were fifteen non-serious adverse events and eight serious adverse events, all likely related to progression of disease or treatment with gemcitabine or erlotinib. Applying RECIST 1.0 criteria, seven of the nine subjects had stable disease while the other two had progressive disease. CONCLUSIONS: These initial safety data do not reveal increased toxicity with the addition of ascorbic acid to gemcitabine and erlotinib in pancreatic cancer patients. This, combined with the observed response to treatment, suggests the need for a phase II study of longer duration. TRIAL REGISTRATION: Clinicaltrials.gov NCT00954525.

  15. Pharmacologic doses of ascorbic acid repress specificity protein (Sp) transcription factors and Sp-regulated genes in colon cancer cells.

    Science.gov (United States)

    Pathi, Satya S; Lei, Ping; Sreevalsan, Sandeep; Chadalapaka, Gayathri; Jutooru, Indira; Safe, Stephen

    2011-01-01

    Ascorbic acid (vitamin C) inhibits cancer cell growth, and there is a controversy regarding the cancer chemoprotective effects of pharmacologic doses of this compound that exhibits prooxidant activity. We hypothesized that the anticancer activity of pharmacologic doses of ascorbic acid (colon cancer cell proliferation and induced apoptosis and necrosis, and this was accompanied by downregulation of Sp1, Sp3, and Sp4 proteins. In addition, ascorbic acid decreased expression of several Sp-regulated genes that are involved in cancer cell proliferation [hepatocyte growth factor receptor (c-Met), epidermal growth factor receptor and cyclin D1], survival (survivin and bcl-2), and angiogenesis [vascular endothelial growth factor (VEGF) and its receptors (VEGFR1 and VEGFR2)]. Other prooxidants such as hydrogen peroxide exhibited similar activities in colon cancer cells, and cotreatment with glutathione inhibited these responses. This study demonstrates for the first time that the anticancer activities of ascorbic acid are due, in part, to ROS-dependent repression of Sp transcription factors.

  16. Shape Evolution Synthesis of Monodisperse Spherical, Ellipsoidal, and Elongated Hematite (alpha-Fe2O3) Nanoparticles Using Ascorbic Acid

    NARCIS (Netherlands)

    Tan, W.F.; Yu, Y.T.; Wang, M.X.; Liu, F.; Koopal, L.K.

    2014-01-01

    Spherical, ellipsoidal, and elongated hematite particles have been obtained via a simple chemical precipitation reaction of FeCl3 and NaOH in the presence of ascorbic acid,(AA). The effects of pH, molar ratio of AA/Fe(III), and time on the formation and shape of the hematite particles were investiga

  17. UlaR activates expression of the ula operon in Streptococcus pneumoniae in the presence of ascorbic acid.

    Science.gov (United States)

    Afzal, Muhammad; Shafeeq, Sulman; Henriques-Normark, Birgitta; Kuipers, Oscar P

    2015-01-01

    In this study, the regulatory mechanism of the ula (utilization of l-ascorbic acid) operon, putatively responsible for transport and utilization of ascorbic acid in Streptococcus pneumoniae strain D39, is studied. β-Galactosidase assay data demonstrate that expression of the ula operon is increased in the presence of ascorbic acid as compared with the effects of other sugar sources including glucose. The ula operon consists of nine genes, including a transcriptional regulator UlaR, and is transcribed as a single transcriptional unit. We demonstrate the role of the transcriptional regulator UlaR as a transcriptional activator of the ula operon in the presence of ascorbic acid and show that activation of the ula operon genes by UlaR is CcpA-independent. Furthermore, we predict a 16 bp regulatory site (5'-AACAGTCCGCTGTGTA-3') for UlaR in the promoter region of ulaA. Deletion of the half or full UlaR regulatory site in PulaA confirmed that the UlaR regulatory site present in PulaA is functional.

  18. Physiological responses of erythrocytes of goats to transportation and the mondulatory role of ascorbic acid.

    Science.gov (United States)

    Minka, Ndazo Salka; Ayo, Joseph Olusegun

    2010-07-01

    Experiments were performed with the aim of investigating the effect of road transportation for 12 hr on erythrocytes of goats during the hot-dry season and the modulatory role of ascorbic acid. Forty 2.5-3-year-old Red Sokoto goats weighing 23-25 kg and belonging to both sexes served as the subjects of the study. Twenty of the goats served as the experimental group and were administered ascorbic acid (AA) per os at a dosage rate of 100 mg/kg body weight; the other 20 served as controls and were given 10 ml each of sterile water. Forty minutes after the administration and loading, the goats were transported for 12 hr. EDTA blood samples collected before loading, after loading, immediately after transportation and subsequently on the 3rd and 7th days of post-transportation were used to determine the red blood cell (RBC) count, packed cell volume (PCV), hemoglobin (Hb), erythrocyte osmotic fragility (EOF), hematimetric (intrinsic) indices and hemoglobin index levels. The obtained results showed that handling, loading and transportation of the control goats induced significant (P<0.05) increases in RBC, Hb, EOF and hypochromic erythrocytes and a decrease (P<0.05) in the volume and average Hb content in RBCs. AA administration ameliorated all these changes. The present results suggest that road transportation for 12 hr during the hot-dry season could induce serious stress, resulting in hemolysis of erythrocytes, which was ameliorated by AA administration. In addition, the results demonstrated that EOF could be used as a diagnostic tool in road transportation stress.

  19. Novel composite material polyoxovanadate@MIL-101(Cr): a highly efficient electrocatalyst for ascorbic acid oxidation.

    Science.gov (United States)

    Fernandes, Diana M; Barbosa, André D S; Pires, João; Balula, Salete S; Cunha-Silva, Luís; Freire, Cristina

    2013-12-26

    A novel hybrid composite material, PMo10V2@MIL-101 was prepared by the encapsulation of the tetra-butylammonium (TBA) salt of the vanadium-substituted phosphomolybdate [PMo10V2O40](5-) (PMo10V2) into the porous metal-organic framework (MOF) MIL-101(Cr). The materials characterization by powder X-ray diffraction, Fourier transform infrared spectra and scanning electron microscopy confirmed the preparation of the composite material without disruption of the MOF porous structure. Pyrolytic graphite electrodes modified with the original components (MIL-101(Cr), PMo10V2), and the composite material PMo10V2@MIL-101 were prepared and their electrochemical responses were studied by cyclic voltammetry. Surface confined redox processes were observed for all the immobilized materials. MIL-101(Cr) showed one-electron reduction process due to chromium centers (Cr(III) → Cr(II)), while PMo10V2 presented five reduction processes: the peak at more positive potentials is attributed to two superimposed 1-electron vanadium reduction processes (V(V) → V(IV)) and the other four peaks to Mo-centred two-electron reduction processes (Mo(VI) → Mo(V)). The electrochemical behavior of the composite material PMo10V2@MIL-101 showed both MIL-101(Cr) and PMo10V2 redox features, although with the splitting of the two vanadium processes and the shift of the Mo- and Cr- centered processes to more negative potentials. Finally, PMo10V2@MIL-101 modified electrode showed outstanding enhanced vanadium-based electrocatalytic properties towards ascorbic acid oxidation, in comparison with the free PMo10V2, as a result of its immobilization into the porous structure of the MOF. Furthermore, PMo10V2@MIL-101 modified electrode showed successful simultaneous detection of ascorbic acid and dopamine.

  20. Protective effect of ascorbic acid in experimental gastric cancer:reduction of oxidative stress

    Institute of Scientific and Technical Information of China (English)

    Claudia P.M.S.Oliveira; Paulo Kassab; Fabio P.Lopasso; Heraldo P. Souza; Mariano Janiszewski; Francisco R. M. Laurindo; Kioshi Iriya; Antonio A.Laudanna

    2003-01-01

    AIM: Oxidative stress participates in the cell carcinogenesis by inducing DNA mutations. Our aim was to assess whether ascorbic acid, an antioxidant, could have a role in preventing ROS (Reactive Oxygen Species) generation in experimental gastric carcinoma in a rat model.METHODS: Experimental gastric cancer was induced in twelve Wistar male rats (weighting 250-350 g) by profound duodeno-gastric reflux throught split gastrojenunostomy. The rats were allocated to the following groups: Group Ⅰ (n=6)was the control; Group Ⅱ (n=6) which was mantained with daily intake of tape water with Vitamin C (30 mg/Kg). After 6 or 12 months, samples of gastric tumor or non tumor mucosa were taken from the anastomosis of both groups.Oxidative stress was measured by superoxide quantification through lucigenin-amplified chemiluminescence base and by staining with Nitrobluetetrazolium. The histopathologic confirmation of adenocarcinoma was made by eosinhemathoxilin method.RESULTS: The intestinal type of gastric adenocarcinoma was microscopically identified in all animals of group Ⅰwhereas only 3 rats of group Ⅱ showed an adenocarcinoma without macroscopic evidence of them. The cancers were located in the anastomosis in all cases. Basal luminescence from tumor gastric tissue generated 38.4±6.8 count per minute/mg/x106 (mean±SD) and 14.9±4.0 count per minute/mg/×106, respectively, in group Ⅰ and Ⅱ animals (P<0.05). The Nitrobluetetrazolium method showed intense staining in tumor tissues but not in non neoplasic mucosa.CONCLUSION: Experimental gastric tumors seem to produce more reactive oxygen species than non neoplasic gastric tissue. The reduction of oxidative stress and gastric tumor incidence in rats were induced by the intake of ascorbic acid. Therefore, it may have a role in the prevention of gastric carcinoma.

  1. Ascorbic acid effect on CIN incidence in diabetic patient after coronary angiography.

    Science.gov (United States)

    Nough, Hossein; Daryachahei, Roya; Hadiani, Leila; Najarzadegan, Mohammad Reza; Mirzaee, Masoud; Hemayati, Roya; Meidani, Mahdy; Mousazadeh, Roya; Namayandeh, Seyedhmahdyeh

    2016-01-01

    This study aims to investigate the antioxidant effect of vitamin C in preventing contrast-induced nephropathy (CIN) in diabetic patients after catheterization. In a double blinded, randomized controlled trial, 90 diabetic patients who were referred for cardiac catheterization were randomly allocated into two arms of vitamin C (A) and placebo (B). The treatment arm (A) received 2 g of vitamin C orally 2 h before catheterization and the control group (B) received 2 g of oral placebo. Six hours before catheterization, patients received fluid resuscitation with normal saline (CIN was considered as a 25% rise in creatinine (Cr) level or an increase of 0.5 mg/dL in earlier creatinine). CIN was compared between groups. Before andthree days after catheterization. Serum Bun - Cr was measured and GFR were calculated. The results were compared between the two groups. Six hours before catheterization, patients received fluid resuscitation with normal saline CIN was compare between arms. Mean GFR in group (A) before procedure was respectively 69.82±19.26 and after the treatment was 81.51±27.40 (P=0.001). But in group (B) it was 74.18±24.41 and 75.20±29.65 (P=0.747). Contrast-induced nephropathy was observed in 10 patients (12.3%) including 3 patients (7.7%) in group (A) and (16.7%, 7 patients) in group (B) (P=0.315). Ascorbic acid intake in diabetic patients prior to use of contrast agents can be effective in maintaining GFR, but the incidence of contrast-induced nephropathy is not associated with the consumption of ascorbic acid.

  2. Phenols and ascorbic acid in black currants (Ribes nigrum L.): variation due to genotype, location, and year.

    Science.gov (United States)

    Vagiri, Michael; Ekholm, Anders; Öberg, Elisabeth; Johansson, Eva; Andersson, Staffan C; Rumpunen, Kimmo

    2013-10-02

    Black currant berries contain many biochemical compounds with proven or potential human health benefits. We studied the content of total and single polyphenols, ascorbic acid, soluble sugars, and titratable acidity for two advanced selections and three cultivars of black currant at two distant locations in Sweden (south: 56°06'N; north: 65°21'N) over a 3 year period. Regression analyses revealed the effect of genotype to be considerably larger than that of location and year. However, significant effects of location, year, and interactions were also revealed. A principal component analysis nevertheless separated the genotypes. The content of ascorbic acid, total phenols, total anthocyanins, and soluble sugars was highest in berries from the south, whereas the content of phenolic acids and titratable acidity was highest in berries from the north. The results show that selection of cultivars and production sites are important for cultivation of high-quality black currant raw material for health-promoting products.

  3. A preliminary study of the electro-oxidation of L-ascorbic acid on polycrystalline silver in alkaline solution

    Science.gov (United States)

    Majari Kasmaee, L.; Gobal, F.

    Electrochemical oxidation of L-ascorbic acid on polycrystalline silver in alkaline aqueous solutions is studied by cyclic voltammetry (CV), chronoamperometry (CA) and impedance spectroscopy (IS). The anodic electro-oxidation starts at -500 mV versus SCE and shows continued anodic oxidation in the cathodic half cycle in the CV regime signifying slowly oxidizing adsorbates. Diffusion coefficient of ascorbate ion measured under both voltammetric regimes is around 1.4 × 10 -5 cm 2 s -1. Impedance spectroscopy measures the capacitances associated with double layer and adsorption around 50 μF cm -2 and 4 mF cm -2 as well as the adsorption and decomposition resistances (rates).

  4. Toward a facile method to remove ascorbate interference in the Folin-Ciocalteu assay of "total phenolic content"

    Science.gov (United States)

    The long-established Folin-Ciocalteu (F-C) assay for total phenolics can have limitations due to interference by ascorbic acid (AsA). For common fruit juices this interference can easily exceed the magnitude of the total phenolic signal itself. Approaches to eliminating the AsA interference are brie...

  5. Effects of GA3, BA, Thiamine and Ascorbic Acid on Some Morphological and Biochemical Characteristics of Periwinkle (Catharanthus roseus L.

    Directory of Open Access Journals (Sweden)

    F. Baniasadi

    2016-07-01

    Full Text Available Introduction: Catharanthus roseus (L. belongs to Apocynaceae family is an important medicinal plant and also cultivated as an ornamental plant almost throughout the tropical and subtropical areas all over the world. Recently, the uses of natural substances are considered very helpful to improve plant growth and development. Application of plant growth regulators (PGRs and vitamins are reported in many horticultural crops. Ascorbic acid is the most abundant antioxidant in plant which protects plant cells. This substance affects cell differentiation and growth. Now a day it is considered as a plant growth regulator. Thiamine or vitamin B1 is water soluble and one of the B complex vitamins. This study was conducted to investigate the effect of the ascorbic acid, thiamine, BA and GA on growth and biochemical parameters of periwinkle. Materials and Methods: The experiment was perform as a completely randomized design with 5 replications at research greenhouse of Shahid Bahonar University of Kerman in 2014.The treatments used include spraying water (control, ascorbic acid 100 mg.l-1, gibberellic acid 100 mg.l-1, thiamine 100 mg.l-1, BA 200 mg. l-1 and combinations of two, three and four of them to determine the response of plants to these substances alone or in combination of them. When the seedlings become on 6-leavs stage, the first foliar spray was carried out. In other two steps was repeated with interval of 10 days. In this study, longevity of the flower, flower diameter, the number of lateral branches, branches length, fresh and dry weight, chlorophyll content and reduced sugars were measured. Chlorophyll content and reduced sugars were measured according to method of Somogy (1952 and Lichtenthder (1987, respectively. Results and Discussion: The results showed that the effect of thiamine on the number of flowers was more pronounced than other substances. The lowest number of flowers per plant was found in plants treated with gibberellic acid

  6. Antitumoral activity of L-ascorbic acid-poly-D,L-(lactide-co-glycolide nanoparticles containing violacein

    Directory of Open Access Journals (Sweden)

    Dorival Martins

    2010-01-01

    Full Text Available Dorival Martins1, Lucas Frungillo2, Maristela C Anazzetti2, Patrícia S Melo3, Nelson Durán11Institute of Chemistry, Biological Chemistry Laboratory, Universidade Estadual de Campinas-UNICAMP, C.P. 6154, CE P 13083-970, Campinas, SP, Brazil; 2Institute of Biology, Cell Cultures and Biopharmaceutical Laboratory, Universidade Estadual de Campinas, UNICAMP, Campinas, SP, Brazil; 3Campinas Integrated Metropolitan Faculties-METROCAMP, Campinas, SP, BrazilAbstract: It has been demonstrated that tumoral cells have a higher uptake of ascorbic acid compared to normal cells. This differential characteristic can be used as a way to improve the specificity of antitumoral compounds if combined with polymeric drug delivery systems. The aim of this study was to prepare, characterize and evaluate the antitumoral activity of poly-D,L-(lactide-co-glycolide 50:50 loading the antitumoral compound violacein and capped with L-ascorbic acid. Nanoparticles were prepared using the nanoprecipitation method and morphologically characterized by scanning electron microscopy (SEM. The average diameter and Zeta potential were determined by photon correlation spectroscopy method (PCS, and assays were carried out to determine the content of ascorbic acid and in vitro drug release kinetics. The antitumoral activity of this system was also evaluated against HL-60 cells by tetrazolium reduction assay. Nanoparticles with size distribution between 300–400 nm and strong negative outer surface (-40 mV were obtained by this method. Analysis of ascorbic acid content showed that this compound was mainly localized on the external surface of nanoparticles. Violacein loading efficiency was determined as 32% ± 1% and this drug was gradually released from nanoparticles at different rates depending on the composition of the release media. In addition, this system was observed to be 2 × more efficient as an antitumoral compared with free violacein.Keywords: violacein, ascorbic acid

  7. The role of topically applied L-ascorbic acid in ex-vivo examination of burn-injured human skin

    Science.gov (United States)

    Pielesz, Anna; Biniaś, Dorota; Bobiński, Rafał; Sarna, Ewa; Paluch, Jadwiga; Waksmańska, Wioletta

    2017-10-01

    Wound treatment and healing is complex and is comprised of an elaborate set of processes including cellular, spectroscopic and biochemical ones as well as the ;reaction; of local tissue to thermal injury. Vitamin C as L-ascorbic acid (LA) prevents injurious effects of oxidants because it reduces reactive oxygen species to stable molecules, it becomes oxidized to the short-lived ascorbyl radical. As a result, antioxidant treatment may contribute to minimizing injury in burn patients. The aim of this study is to assess changes in molecular structure of collagen extracted from human epidermis burn wound scab during incubation of the epidermis in L-ascorbic acid solution. The study will be performed using FTIR and FT Raman spectroscopies. During this research it was observed that the intensity of Raman peaks increased where healing was being modified by LA. The intensity of the amide III band at 1247 cm- 1 relative to the intensity at 1326 cm- 1 was used to test tissue repair degree at the incision site. FTIR spectra were recorded from frozen specimens of serum modified by LA; an analysis of shifts in the amide I band position was conducted. The appearance of a new band for frozen samples modified by LA was observed around 1149-1220 cm- 1. The above conclusions confirmed the creation of hydrogen bonds between Nsbnd H stretch and Cdbnd O. Samples being incubated in solutions of L-ascorbic acid demonstrated the absence of electrophoretic bands of albumin. Alterations in the surface of the skin incubated in L-ascorbic acid were investigated with the use of Scanning Electron Microscopy (SEM). A decrease in external symptoms of burn injury was noted in the damaged epidermis incubated in L-ascorbic acid.

  8. Use of ionic chromatography in determining the contamination of apple juice by lactic acid.

    Science.gov (United States)

    Wojtczak, M; Antczak, A; Przybyt, M

    2010-06-01

    High-performance anion exchange chromatography (HPAEC) with conductometric detection was used for the determination of the lactic acid content of apple juice subjected to fermentation with the strains of Lactobacillus brevis and Lactobacillus plantarum, obtained from a collection, at 20 and 30 degrees C. At the same time, lactate content was determined by means of enzymatic tests and biosensors. Lactic acid concentrations determined by the chromatographic method are similar to those obtained during analysis by enzymatic tests. However, acid concentrations determined by means of biosensors substantially diverge from these results.

  9. Clinical evaluation of Moro (Citrus sinensis (L.) Osbeck) orange juice supplementation for the weight management.

    Science.gov (United States)

    Cardile, Venera; Graziano, Adriana Carol Eleonora; Venditti, Alessandro

    2015-01-01

    In the last years, several studies have recently evaluated the beneficial effects of red orange juice (Citrus sinensis (L.) Osbeck) and its active components in weight management and obesity. Moro orange is a cultivar of red orange, particularly rich in active compounds such as anthocyanins, hydroxycinnamic acids, flavone glycosides and ascorbic acid, which displays anti-obesity effects in in vitro and in vivo studies. In this clinical study, the effect of a Moro juice extract (Morosil(®), 400 mg/die) supplementation was evaluated in overweight healthy human volunteers for 12 weeks. Results showed that Moro juice extract intake was able to induce a significant reduction in body mass index (BMI) after 4 weeks of treatment (p juice have a synergistic effect on fat accumulation in humans and Moro juice extract can be used in weight management and in the prevention of human obesity.

  10. Fermentation of Agave tequilana juice by Kloeckera africana: influence of amino-acid supplementations.

    Science.gov (United States)

    Valle-Rodríguez, Juan Octavio; Hernández-Cortés, Guillermo; Córdova, Jesús; Estarrón-Espinosa, Mirna; Díaz-Montaño, Dulce María

    2012-02-01

    This study aimed to improve the fermentation efficiency of Kloeckera africana K1, in tequila fermentations. We investigated organic and inorganic nitrogen source requirements in continuous K. africana fermentations fed with Agave tequilana juice. The addition of a mixture of 20 amino-acids greatly improved the fermentation efficiency of this yeast, increasing the consumption of reducing sugars and production of ethanol, compared with fermentations supplemented with ammonium sulfate. The preference of K. africana for each of the 20 amino-acids was further determined in batch fermentations and we found that asparagine supplementation increased K. africana biomass production, reducing sugar consumption and ethanol production (by 30, 36.7 and 45%, respectively) over fermentations supplemented with ammonium sulfate. Therefore, asparagine appears to overcome K. africana nutritional limitation in Agave juice. Surprisingly, K. africana produced a high concentration of ethanol. This contrasts to poor ethanol productivities reported for other non-Saccharomyces yeasts indicating a relatively high ethanol tolerance for the K. africana K1 strain. Kloeckera spp. strains are known to synthesize a wide variety of volatile compounds and we have shown that amino-acid supplements influenced the synthesis by K. africana of important metabolites involved in the bouquet of tequila. The findings of this study have revealed important nutritional limitations of non-Saccharomyces yeasts fermenting Agave tequilana juice, and have highlighted the potential of K. africana in tequila production processes.

  11. Promoting extracellular matrix remodeling via ascorbic acid enhances the survival of primary ovarian follicles encapsulated in alginate hydrogels.

    Science.gov (United States)

    Tagler, David; Makanji, Yogeshwar; Tu, Tao; Bernabé, Beatriz Peñalver; Lee, Raymond; Zhu, Jie; Kniazeva, Ekaterina; Hornick, Jessica E; Woodruff, Teresa K; Shea, Lonnie D

    2014-07-01

    The in vitro growth of ovarian follicles is an emerging technology for fertility preservation. Various strategies support the culture of secondary and multilayer follicles from various species including mice, non-human primate, and human; however, the culture of early stage (primary and primordial) follicles, which are more abundant in the ovary and survive cryopreservation, has been limited. Hydrogel-encapsulating follicle culture systems that employed feeder cells, such as mouse embryonic fibroblasts (MEFs), stimulated the growth of primary follicles (70-80 µm); yet, survival was low and smaller follicles (structure and degenerated. These morphologic changes were associated with a breakdown of the follicular basement membrane; hence, this study investigated ascorbic acid based on its role in extracellular matrix (ECM) deposition/remodeling for other applications. The selection of ascorbic acid was further supported by a microarray analysis that suggested a decrease in mRNA levels of enzymes within the ascorbate pathway between primordial, primary, and secondary follicles. The supplementation of ascorbic acid (50 µg/mL) significantly enhanced the survival of primary follicles (alginate hydrogels, which coincided with improved structural integrity. Follicles developed antral cavities and increased to diameters exceeding 250 µm. Consistent with improved structural integrity, the gene/protein expression of ECM and cell adhesion molecules was significantly changed. This research supports the notion that modifying the culture environment (medium components) can substantially enhance the survival and growth of early stage follicles. © 2013 Wiley Periodicals, Inc.

  12. Influence of ascorbic acid on in vivo amidation of alpha-melanocyte stimulating hormone in guinea pig pituitary

    DEFF Research Database (Denmark)

    Fenger, M; Hilsted, L

    1988-01-01

    The effect of ascorbic acid depletion on the amidation of alphamelanocyte stimulating hormone (alpha MSH) was studied in vivo in guinea pig pituitary. After four weeks, the concentration of ascorbic acid was 1.20 +/- 0.11 mumol/g tissue (mean +/- SD) in the pituitary and 0.34 +/- 0.07 mumol....../g tissue in the cerebral cortex from the depleted animals versus 7.58 +/- 0.08 and 1.51 +/- 0.32 mumol/g tissue, respectively, in the control animals. In the pituitaries from the animals depleted of ascorbate (N = 4), the relative amount of alpha MSH was reduced to approximately half the values obtained......-39) immunoreactivity was observed in the depleted guinea pigs. Gel chromatography and reversed-phase high-performance luquid chromatography showed that the alpha MSH and ACTH (1-14) immunoreactivity was of low molecular weight and partly mono- or diacetylated. Depletion of ascorbic acid had no influence on the degree...

  13. A biosensor based on zucchini (Cucurbita pepo L.) homogenate as a biorecognition layer for ascorbic acid determination.

    Science.gov (United States)

    Sezgintürk, Mustafa Kemal; Koca, Halit Buğra; Ozben, Yavuz Selim; Dinçkaya, Erhan

    2010-08-01

    An amperometric biosensor based on zucchini (Cucurbita pepo) tissue homogenate is presented. The zucchini tissue homogenate was crosslinked with gelatine using glutaraldehyde and fixed on a pretreated teflon membrane. The zucchini tissue contained the enzyme ascorbate oxidase and this enzyme catalyzed the oxidation of ascorbic acid in the presence of dissolved oxygen. The principle of the measurements was based on the determination of the decrease in the dissolved oxygen level. Determinations were carried out by standard curves, which were obtained by the measurement of the decrease in the oxygen level related to ascorbic acid concentration. Optimization and characterization studies of the biosensor were carried out in detail. First of all, the amounts of zucchini tissue homogenate, gelatin, and glutaraldehyde percentage were optimized. Experimental parameters such as buffer system, pH, buffer concentration, and temperature were also optimized carefully. Thermal stability, storage stability, and repeatability of the biosensor were investigated. A linear response was observed from 5x10(-6) M to 1.2x10(-3) M ascorbic acid. Finally, the results of some plant and drug samples analyzed with the presented biosensor compared with the spectrophotometric method (Tillman reagent) used as a reference.

  14. A pulse radiolysis study of the dynamics of ascorbic acid free radicals within a liposomal environment.

    Science.gov (United States)

    Kobayashi, Kazuo; Seike, Yumiko; Saeki, Akinori; Kozawa, Takahiro; Takeuchi, Fusako; Tsubaki, Motonari

    2014-10-06

    The dynamics of free-radical species in a model cellular system are examined by measuring the formation and decay of ascorbate radicals within a liposome with pulse radiolysis techniques. Upon pulse radiolysis of an N2O-saturated aqueous solution containing ascorbate-loaded liposome vesicles, ascorbate radicals are formed by the reaction of OH(·) radicals with ascorbate in unilamellar vesicles exclusively, irrespective of the presence of vesicle lipids. The radicals are found to decay rapidly compared with the decay kinetics in an aqueous solution. The distinct radical reaction kinetics in the vesicles and in bulk solution are characterized, and the kinetic data are analyzed.

  15. Selective Voltammetric Determination of Uric Acid in the Presence of Ascorbic Acid at Ordered Mesoporous Carbon Modified Electrodes

    Institute of Scientific and Technical Information of China (English)

    WEN,Yan-Li; JIA,Neng-Qin; WANG,Zhi-Yong; SHEN,He-Bai

    2008-01-01

    A novel chemically modified electrode was fabricated by immobilizing ordered mesoporous carbon (OMC)onto a glassy carbon (GC) electrode.The electrocatalytic behavior of the OMC modified electrode towards the oxidation of uric acid (UA) and ascorbic acid (AA) was studied.Compared to a glassy carbon electrode,the OMC modified electrode showed a faster electron transfer rate and reduced the overpotentials greatly.Furthermore,the OMC modified electrode resolved the overlapping voltammetric responses of UA and AA into two well-defined voltammetric peaks with peak separation of ca.0.38 V.All results show that the OMC modified electrode has a good electrocatalytic ability to UA and AA,and has an excellent response towards UA even in the presence of high concentration AA.

  16. Antagonism between abscisic acid and gibberellins is partially mediated by ascorbic acid during seed germination in rice.

    Science.gov (United States)

    Ye, Nenghui; Zhang, Jianhua

    2012-05-01

    The antagonism between abscisic acid (ABA) and gibberellin (GA) plays a key role in controlling seed germination, but the mechanism of antagonism during this process is not known. In the associated study, we investigated the relationship among ABA, reactive oxygen species (ROS), ascorbic acid (ASC) and GA during rice seed germination. ROS production is reduced by ABA, which hence results in decreasing ASC accumulation during imbibition. GA accumulation was also suppressed by a reduced ROS and ASC level, whereas application of exogenous ASC can partially rescue seed germination from ABA treatment. Further results show that production of ASC, which acts as a substrate in GA biosynthesis, was significantly inhibited by lycorine which thus suppressed the accumulation of GA. Consequently, expression of GA biosynthesis genes was suppressed by the low levels of ROS and ASC in ABA-treated seeds. These studies reveal a new role for ASC in mediating the antagonism between ABA and GA during seed germination in rice.

  17. Study on the Ascorbic Acid Content of rose Hip fruit Depending on Stationary Conditions

    Directory of Open Access Journals (Sweden)

    Sorina Ropciuc

    2011-10-01

    Full Text Available The dog rose area includes southern and central Europe, reaching southern Scandinavia; it is also found in Asia Minor, Central Asia and North Africa. In our country, Rosa canina is the most widespread of the many species of Rosa, common in all areas. The components of the station, known also as the „stationary factors” affect differently the plant life and their chemical composition. Cynosbati fructus is the false fruit of Rosa canina L. (Rosaceae, known in Romanian as rose hip. The rose hip contain as active ingredients 500-1000 % vitamin C, 600-10000 mg% carotenoids, pectin, dextrin, vitamins B2, E, PP, flavone, sugars, organic acids, tannins, volatile oil, vanillin, triterpenoid saponosides, beta-sitosterol, fat (lecithin, glycerides of fatty acids in seeds, minerals (potassium, calcium, magnesium, iron. Vitamin C (ascorbic acid plays an important role in human body. The greatest amount is found in plants which reached maturity. It is concentrated in the rose hip flesh. Solutions easily destroyit in the presence of UV, of copper, silver, iron and oxidative enzymes traces. Vitamin C participates actively in all processes of oxidoreductions of the living cell. Its lack in food causes the disease called scurvy which manifests itself by inflammated and bleeding gums, tooth loss. Rose hip fruits are known as medicines since prehistoric times.

  18. Role of ascorbic acid and α tocopherol in alleviating salinity stress on flax plant (Linum usitatissimum L.

    Directory of Open Access Journals (Sweden)

    Mervat Sh. Sadak

    2014-03-01

    Full Text Available Salinity is one of the environmental challenges in the world affecting on several physiological processes and the most limiting factor of plant productivity and quality. Two pot experiments were conducted at the wire house of National Research Centre, Cairo, Egypt during two successive seasons of 2010/2011 and 2011/2012 to assess the efficiency of two antioxidant vitamins (ascorbic acid at 1.13 and 2.27 mM or α tocopherol at 0.46 and 0.93 mM and/or salinity stress at (0.0, 3.08, 6.16, 9.23 ds/m on photosynthetic pigments, protein, carbohydrate, minerals, oil contents and yield as well as fatty acids composition of the yielded oils of three flax cultivars (Sakha 3, Giza 8 and Ariane. The data revealed that salinity stress caused significant and gradual decreases in total photosynthetic pigments, polysaccharides, total carbohydrates, total proteins and the uptake of Mg, K, Ca and P in the leaves of three flax cultivars with increasing salinity levels (3.08, 6.16, 9.23 ds/m. Otherwise, significant and gradual increase appeared in both Na and Cl. Ascorbic acid and α tocopherol at different concentrations caused significant increases in photosynthetic pigments, total carbohydrates and protein contents in the leaves of flax plants irrigated either with tap water or saline solution as compared with their corresponding controls. Exogenous application of ascorbic and α tocopherol at different concentrations exhibited decreases in Na and Cl whereas increases appeared in Mg, K, Ca and P relative to their corresponding control. Ascorbic acid (1.13 and 2.27 mM and α tocopherol (0.46 and 0.93 mM caused marked increases in yield and yield attributes of three flax cultivars either in plants irrigated with tap water or saline solution as compared to corresponding control. Ascorbic acid effects were more pronounced than α tocopherol effects. In addition, the higher level of two vitamins was more pronounced than the lower level. Regarding plants irrigated

  19. The graphene nanopowder for electro-catalytic oxidation of dopamine and uric acid in the presence of ascorbic acid

    Institute of Scientific and Technical Information of China (English)

    Yuan; Bu; Wenle; Dai; Nan; Li; Xinran; Zhao; Xia; Zuo

    2013-01-01

    The graphene nanopowder for electro-catalytic oxidation of dopamine and uric acid in the presence of ascorbic acid has been investigated by cyclic voltammetry,linear polarization and chronoamperometry.The graphene nanopowder modified electrode was prepared using the drop coating method,which displayed excellent electrocatalytic activity towards the oxidation of dopamine and uric acid compared with the bare glassy carbon electrode in phosphate buffer solution at pH=7.0.Linear responses for dopamine and uric acid were obtained in the ranges of3.3μmol/L to 249.1μmol/L and 6.7μmol/L to 386.3μmol/L with detection limits of 1.5μmol/L and 2.7μmol/L(S/N=3),respectively.The response time was less than 2 s in case of dopamine and 3 s in case of uric acid,respectively.The results demonstrated that the graphene nanopowder had potential for detecting dopamine and uric acid.

  20. Effect of autochthonous lactic acid bacteria starters on health-promoting and sensory properties of tomato juices.

    Science.gov (United States)

    Di Cagno, Raffaella; Surico, Rosalinda F; Paradiso, Annalisa; De Angelis, Maria; Salmon, Jean-Christophe; Buchin, Solange; De Gara, Laura; Gobbetti, Marco

    2009-01-15

    Strains of Lactobacillus plantarum, Weissella cibaria/confusa, Lactobacillus brevis, Pediococcus pentosaceous, Lactobacillus sp. and Enterococcus faecium/faecalis were identified from raw tomatoes by Biolog System, partial 16S rRNA gene sequence and subjected to typing by Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) analysis. Ten autochthonous strains were singly used to ferment tomato juice (TJ) via a protocol which included fermentation at 25 degrees C for 17 h and further storage at 4 degrees C for 40 days. Unstarted TJ and TJ fermented with an allochthonous strain of L. plantarum were used as the controls. All autochthonous strains grew well in TJ reaching cell densities ca. 10,000 and 10 times higher than unstarted TJ and TJ fermented with the allochthonous strain. Viscosity of TJs fermented with autochthonous strains was generally the highest, especially when started with W. cibaria/confusa which synthesized exo-polysaccharides. Overall, unstarted TJ and TJ fermented with the allochthonous strain showed marked decreases of ascorbic acid (ASC), glutathione (GSH) and total antioxidant activity (TTA) during storage. On the contrary, several TJs fermented with autochthonous strains, especially with L. plantarum POM1 and POM 35, maintained elevated values of ASC, GSH and TAA. The variation of color indexes mirrored the above behavior. TJs fermented with the above two autochthonous strains were compared to controls based on volatile components through Purge and Trap or Solid Phase Microextraction Gas Chromatography-Mass Spectrometry (PT or SPME-GC/MS) analysis. As shown by Principal Component Analysis a large number of volatiles belonging to various chemical classes markedly differentiated TJs fermented with autochthonous strains with respect to controls.

  1. Color and chemical stability of a variety of anthocyanins and ascorbic acid in solution and powder forms.

    Science.gov (United States)

    West, Megan E; Mauer, Lisa J

    2013-05-01

    The color and chemical stabilities of six anthocyanins, including cyanidin 3-glucoside, highly purified and present in semipurified extracts (also containing other anthocyanins) from grape pomace, purple corn, and black rice, were determined in combination with ascorbic acid in solutions at differing pH values (3.0 and 4.0) and temperatures (6-40 °C) and lyophilized powders at different relative humidities (43-98% RH). Color and chemical changes were analyzed using CIELAB measurements and HPLC, respectively. In liquids, stability was inversely related to increasing pH and temperature; for powders, stability was inversely related to RH. The mutual destruction of anthocyanins and ascorbic acid in solution was confirmed, with unexpected new findings showing no significant stabilizing/destabilizing effect based upon anthocyanin structure, including differing flavylium core (three types) and type of acylation (two aliphatic, one cinnamic acid), or final extract purity.

  2. Radiolabelling of ascorbic acid: a new clue to clarify its action as an anticancer agent?

    Science.gov (United States)

    Mamede, A C; Abrantes, A M; Pires, A S; Tavares, S D; Serra, M E; Maia, J M; Botelho, M F

    2012-04-01

    Vitamin C exists in two forms: the reduced (ascorbic acid--AA) and oxidized form (dehydroascorbic acid--DHA). This is a nutrient whose benefits are long known and widely publicized, being most of them related to its antioxidant action. As an antioxidant, the main role of vitamin C is to neutralize free radicals, reducing oxidative stress. However, some controversial studies suggest that this nutrient may have a preventive and therapeutic role in cancer disease due to their possible pro-oxidant activity, promoting the formation of reactive oxygen species that can induce cell death in cancer cells. This factor, coupled with the decrease of antioxidant enzymes and increase of decompartmentalized transition metals in tumor cells may result in the selective cytotoxicity of vitamin C and the subsequent revelation of its therapeutic potential. In this way the first purpose of this work was radioactively label the reduced form of vitamin C with Tc-99m, its quality control by HPLC and the time stability. The second purpose was to use the radioactive complex 99mTc-AA in in vitro and in vivo studies in order to evaluate its uptake by colorectal cancer cells and biodistribution in mices, respectively. The results suggest that the pharmaceutical formulation developed, which was reproducible and stable over time, was residually taken up by colorectal cancer cells. Future studies are needed to deepen our understanding about the radioactive complex 99mTc-AA and clarify the mechanisms of action of vitamin C in oncologic disease.

  3. Synergistic protective role of ceftriaxone and ascorbic acid against subacute diazinon-induced nephrotoxicity in rats.

    Science.gov (United States)

    Abdel-Daim, Mohamed M

    2016-03-01

    Diazinon (DZN) is a synthetic organophosphrus acaricide and insecticide widely used for veterinary and agricultural purposes. However, its animal and human exposure leads to nephrotoxicity. Our experimental objective was to evaluate protective effects of ceftriaxone and/or ascorbic acid-vitamin C against DZN-induced renal injury in male Wistar albino rats. DZN-treated animals revealed significant elevation in serum biochemical parameters related to renal injury: urea, uric acid and creatinine. DZN intoxication significantly increased renal lipid peroxidation, and significant inhibition in antioxidant biomarkers including, reduced glutathione, glutathione peroxidase, superoxide dismutase, catalase and total antioxidant capacity. In addition, DZN significantly reduced serum acetylcholinestrase level. Moreover, It induced serum and kidney tumor necrosis factor-α level. Both ceftriaxone and vitamin C protect against DZN-induced serum as well as renal tissue biochemical parameters when used alone or in combination along with DZN-intoxication. Furthermore, both ceftriaxone and vitamin C produced synergetic nephroprotective and antioxidant effects. Therefore, it could be concluded that ceftriaxone and/or vitamin C administration are able to minimize the toxic effects of DZN by its free radical-scavenging and potent antioxidant activity.

  4. Sub-millitesla magnetic field effects on the recombination reaction of flavin and ascorbic acid radicals

    Science.gov (United States)

    Evans, Emrys W.; Kattnig, Daniel R.; Henbest, Kevin B.; Hore, P. J.; Mackenzie, Stuart R.; Timmel, Christiane R.

    2016-08-01

    Even though the interaction of a acid. Direct control of the reaction pathway is achieved by varying the rate of electron transfer from ascorbic acid to the photo-excited flavin. At pH 7.0, we verify the theoretical prediction that, apart from a sign change, the form of the magnetic field effect is independent of the initial spin configuration of the radical pair. The data agree well with model calculations based on a Green's function approach that allows multinuclear spin systems to be treated including the diffusive motion of the radicals, their spin-selective recombination reactions, and the effects of the inter-radical exchange interaction. The protonation states of the radicals are uniquely determined from the form of the magnetic field-dependence. At pH 3.0, the effects of two chemically distinct radical pair complexes combine to produce a pronounced response to ˜500 μT magnetic fields. These findings are relevant to the magnetic responses of cryptochromes (flavin-containing proteins proposed as magnetoreceptors in birds) and may aid the evaluation of effects of weak magnetic fields on other biologically relevant electron transfer processes.

  5. Lipophilization of ascorbic acid: a monolayer study and biological and antileishmanial activities.

    Science.gov (United States)

    Kharrat, Nadia; Aissa, Imen; Sghaier, Manel; Bouaziz, Mohamed; Sellami, Mohamed; Laouini, Dhafer; Gargouri, Youssef

    2014-09-17

    Ascorbyl lipophilic derivatives (Asc-C2 to Asc-C(18:1)) were synthesized in a good yield using lipase from Staphylococcus xylosus produced in our laboratory and immobilized onto silica aerogel. Results showed that esterification had little effect on radical-scavenging capacity of purified ascorbyl esters using DPPH assay in ethanol. However, long chain fatty acid esters displayed higher protection of target lipids from oxidation. Moreover, compared to ascorbic acid, synthesized derivatives exhibited an antibacterial effect. Furthermore, ascorbyl derivatives were evaluated, for the first time, for their antileishmanial effects against visceral (Leishmania infantum) and cutaneous parasites (Leishmania major). Among all the tested compounds, only Asc-C10, Asc-C12, and Asc-C(18:1) exhibited antileishmanial activities. The interaction of ascorbyl esters with a phospholipid monolayer showed that only medium and unsaturated long chain (Asc-C10 to Asc-C(18:1)) derivative esters were found to interact efficiently with mimetic membrane of leishmania. These properties would make ascorbyl derivatives good candidates to be used in cosmetic and pharmaceutical lipophilic formulations.

  6. Mechanisms of the influence of UV irradiation on collagen and collagen-ascorbic acid solutions

    Directory of Open Access Journals (Sweden)

    N. Metreveli

    2006-01-01

    Full Text Available The study of the influence of UV irradiation on collagen solutions has shown the destabilization of the collagen molecule by calorimetric method. It is reflected both in changes of thermodynamic parameters of transition (Tm, ΔH, Cp=f(t and in the appearance of a low temperature peak, that is practically irreversible against rescanning. All these indicate that the important defects in the molecule occur. The ESR measurements have shown that the above-mentioned thermal changes are connected with the occurrence of free radicals in solution under UV irradiation. They interact with proline (Pro residues of the protein with the appearance of secondary free radicals, with following migration to glycine (Gly residues. The emergence of the free radicals at the Pro and then at the Gly residues may cause the dramatic structural defect resulting from the UV irradiation, which significantly alters the network of hydrogen bonds in the triple helix of the collagen molecule. All this is connected with destabilization of the collagen molecule, because the defects in amino acid residues probably lead to cleavage of covalent bonds near the damaged sites maintaining the triple helical structure. The presence of ascorbic acid in collagen solution protects the collagen molecule from occurring of secondary free radicals.

  7. Betalain, Acid ascorbic, phenolic contents and antioxidant properties of purple, red, yellow and white cactus pears.

    Science.gov (United States)

    Sumaya-Martínez, María Teresa; Cruz-Jaime, Sandra; Madrigal-Santillán, Eduardo; García-Paredes, Juan Diego; Cariño-Cortés, Raquel; Cruz-Cansino, Nelly; Valadez-Vega, Carmen; Martinez-Cardenas, Leonardo; Alanís-García, Ernesto

    2011-01-01

    Commercialization of cactus pears based on their antioxidant properties can generate competitive advantages, and these can turn into business opportunities and the development of new products and a high-value ingredient for the food industry. This work evaluated the antioxidant activities (1,1-diphenyl-2-picrylhydrazyl radical-scavenging, protection against oxidation of a β-carotene-linoleic acid emulsion, and iron (II) chelation), the content of total phenolic compounds, ascorbic acid, betacyanin, betaxanthin and the stability of betacyanin pigments in presence of Cu (II)-dependent hydroxyl radicals (OH•), in 18 cultivars of purple, red, yellow and white cactus pear from six Mexican states. Our results indicated that the antiradical activities from yellow and white cactus pear cultivars were not significantly different (p cactus pear from the state of Zacatecas showed the highest antioxidant activity. The free radical scavenging activity for red cactus pears was significantly correlated (p cactus pears studied showed significant chelating activity of ferrous ions. The red and purple cactus pears showed a great stability when exposed to OH•.

  8. Ascorbic acid, garlic extract and taurine alleviate cadmium-induced oxidative stress in freshwater catfish (Clarias batrachus)

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Puneet, E-mail: puneetbiochem@gmail.com [Aquatic Biotechnology and Fish Pathology Laboratory, Department of Animal Science, M.J.P. Rohilkhand University, Bareilly-243 006 (India); Prasad, Y. [Aquatic Biotechnology and Fish Pathology Laboratory, Department of Animal Science, M.J.P. Rohilkhand University, Bareilly-243 006 (India); Patra, A.K. [West Bengal University of Animal and Fishery Sciences, Kolkata-700037 (India); Ranjan, R.; Swarup, D.; Patra, R.C. [Division of Medicine, Indian Veterinary Research Institute, Izatnagar-243122 (India); Pal, Satya [Env. Eng. Lab., Deptt. of Civil Engineering, I.I.T., Roorkee-247667 (India)

    2009-09-01

    An experiment was conducted to investigate bioaccumulation potential of cadmium (Cd) and changes in oxidative stress indices in liver and kidney tissues from Cd-exposed catfish (Clarias batrachus) with or without simultaneous treatment of water with ascorbic acid, garlic extract or taurine. C. batrachus (n = 324) with average length of 20 {+-} 4 cm and weight of 86 {+-} 5 g were used for the present investigation. Fishes were divided into nine groups (I to IX) each comprising 36 fishes. The fishes of groups II, III, IV and V were challenged with 5 ppm of cadmium chloride monohydrate (CdCl{sub 2}.H{sub 2}O), whereas groups VI, VII, VIII and IX were exposed to 10 ppm CdCl{sub 2}.H{sub 2}O solution for a period of 45 days. Group I was kept as negative control and the fishes of this group were maintained in water containing no added Cadmium. Group II and VI were maintained as Cd exposed non treated control to serve as positive controls. Fishes of III and VII, IV and VIII, V and IX received ascorbic acid (5 ppm), extract of dried garlic (5 ppm) or taurine (5 ppm), respectively during the entire experiment period. The concentrations of Cd in liver and kidney increased significantly following exposure to Cd and the level continued to rise with the increase in exposure duration. Treatment of tank water with ascorbic acid, garlic or taurine significantly reduced the Cd concentrations in tissues compared to the positive control group, but the level in Cd exposed groups was greater than the negative control group. Fishes exposed to Cd and treated with ascorbic acid, garlic or taurine had reduced oxidative stress as evidenced from lower concentration of lipid peroxides and higher activities of superoxide dismutase and catalase in liver, kidney and erythrocytes compared to fishes exposed to Cd. The reduction in Cd induced oxidative stress was highest in ascorbic acid treated group followed by garlic and taurine treatment. The results suggest that ascorbic acid, garlic and

  9. Effects of heat, pH, antioxidant, agitation and light on betacyanin stability using red-fleshed dragon fruit (Hylocereus polyrhizus) juice and concentrate as models.

    Science.gov (United States)

    Wong, Yen-Ming; Siow, Lee-Fong

    2015-05-01

    Red-fleshed dragon fruit (Hylocereus polyrhizus) is rich in antioxidants. The aim of this study was to determine the effects of heat pasteurization, pH adjustment, ascorbic acid addition as well as storage under agitation and light or dark condition on betacyanin content in red-fleshed dragon fruit (Hylocereus polyrhizus) juice and concentrate. The concentrate was produced by concentrating clarified red-fleshed dragon fruit juice in a rotary evaporator at 40 °C. UV-Visible spectrophotometer was used for analyzing betacyanin content. Addition of 0.25 % ascorbic acid, pH 4.0, and pasteurization at 65 °C for 30 min were selected as the best processing conditions to retain betacyanin content in red-fleshed dragon fruit juice. Storage at the agitation speed of 220 rpm showed that the concentrated samples had higher betacyanin stability compared to juice, while both juice and concentrate had almost similar betacyanin stability when tested for storage in the presence of light. In summary, ascorbic acid stabilized betacyanin in both juice and concentrate at agitated or non-agitated conditions. In contrast, light degraded betacyanin in both juice and concentrate models.

  10. Stability of cashew apple juice in powder dehydrated in spouted bed

    Directory of Open Access Journals (Sweden)

    Sanyelle L. Sousa

    Full Text Available ABSTRACT This study evaluated the stability of cashew apple juice in powder, dehydrated in spouted bed and stored in two vacuum-sealed packages (laminated and plastic for a period of 60 days. The parameters evaluated in this study were ascorbic acid, carotenoids, moisture, water activity, hygroscopicity, degree of caking, solubility and rehydration. Decreases in the contents of ascorbic acid and carotenoids were observed after 60 days. Moisture content remained practically unchanged during storage, and water activity showed a rising trend in the plastic package. In both packages, the powder showed low hygroscopicity and high caking formation. The solubility in both packages was higher than 90% and the time of rehydration of cashew apple juice in powder in the plastic package increased during storage. Cashew apple juice in powder stored in laminated package preserved better its physical and physico-chemical properties.

  11. Effects of Enzymatic Treatment on Physicochemical Properties of Sugar Palm Fruit Juice

    Directory of Open Access Journals (Sweden)

    Arsad P

    2015-01-01

    Full Text Available The interest in fruit and vegetable juices production has increased significantly all over the world due to their benefit value, quality of production and increasing of consumer awareness and preference for healthy food. The production of sugar palm (Arenga pinnata fruit juice with exotic characteristics has the potential to be explored based on the new technologies and methods in juices industry. In beverage industry, enzyme is an essential tool for quality improvement and cost saving by increasing the yield of the fruit juice. The purpose of this study is to determine the effects of different enzymatic treatment on sugar palm fruit juice processing. Sugar palm fruit purees were treated individually and in combination using two types of commercial enzymes: Novozymes Cellulase and Pectinex Ultra SP-L at a concentration of 0.05% (w/w and incubated at 45°C for 60 min. The results showed that there are significant (p<0.05 reduction on proximate content such as crude fibre, crude protein and carbohydrate for the enzymes treated juices as compared to the untreated juice. The enzyme treatment also significantly (p<0.05 reduced the juice viscosity and ascorbic acid content, promoted juice clarification and increased L value, yield, TSS and sugar content. In conclusion, the quality of sugar palm fruit juice can be improved by using the combination treatment of pectinase and cellulase enzymes.

  12. Low-volume plus ascorbic acid vs high-volume plus simethicone bowel preparation before colonoscopy

    Institute of Scientific and Technical Information of China (English)

    Stefano Pontone; Rita Angelini; Monica Standoli; Gregorio Patrizi; Franco Culasso; Paolo Pontone; Adriano Redler

    2011-01-01

    AIM: To investigate the effectiveness of low-volume plus ascorbic acid [polyethylene glycol plus ascorbic acid (PEG + Asc)] and high-volume plus simethicone [polyethylene glycol plus simethicone (PEG + Sim)] bowel preparations.METHODS: A total of one hundred and forty-four outpatients (76 males), aged from 20 to 84 years (me dian age 59.5 years), who attended our Department, were divided into two groups, age and sex matched, and underwent colonoscopy. Two questionnaires, one for patients reporting acceptability and the other for endoscopists evaluating bowel cleansing effectiveness according to validated scales, were completed. Indica tions, timing of examination and endoscopical findings were recorded. Biopsy forceps were used as a measur ing tool in order to determine polyp endoscopic sizeestimation. Difficulty in completing the preparation was rated in a 5-point Likert scale (1 = easy to 5 = un able). Adverse experiences (fullness, cramps, nausea, vomiting, abdominal pain, headache and insomnia), number of evacuations and types of activities per formed during preparation (walking or resting in bed) were also investigated.RESULTS: Seventy-two patients were selected for each group. The two groups were age and sex matched as well as being comparable in terms of medical history and drug therapies taken. Fourteen patients dropped out from the trial because they did not complete the preparation procedure. Ratings of global bowel cleans ing examinations were considered to be adequate in 91% of PEG + Asc and 88% of PEG + Sim patients. Residual Stool Score indicated similar levels of amount and consistency of residual stool; there was a signifi cant difference in the percentage of bowel wall visuali zation in favour of PEG + Sim patients. In the PEG + Sim group, 12 adenomas < 10 mm diameter (5/left co lon + 7/right colon) vs 9 (8/left colon + 1/right colon) in the PEG + Asc group were diagnosed. Visualization of small lesions seems to be one of the primary advan tages of

  13. Therapeutic efficiency of succimer used with calcium and ascorbic acid in the treatment of mild lead-poisoning.

    Science.gov (United States)

    Jin, Yaping; Yu, Fei; Liao, Yingjun; Liu, Shaoxia; Liu, Meimei; Xu, Jianhong; Yang, Jun

    2011-01-01

    The aim of this study was to explore therapeutic efficiency of succimer used with calcium and ascorbic acid in the treatment of mildly lead-poisoned mice and preschool children. Mice were exposed to lead by drinking water, and then treated with saline solution, 50mg/kg body weight (b.w.) succimer, 100mg/kg b.w. succimer, or 50mg/kg b.w. succimer plus calcium and ascorbic acid by gavage. Seventy-two children aged 48-72 months were randomly assigned into combined treatment or nutritional intervention group. Lead levels in blood and bone were analyzed by atomic absorption spectrophotometry. Activities of aminolevulinic acid dehydratase (ALAD) in blood were determined by colorimetric method. Results of animal experiment showed that succimer used alone could reduce lead levels in blood and bone and reverse activities of ALAD in blood, however, a better therapeutic efficiency in mobilizing bone lead could be achieved by succimer used with calcium and ascorbic acid. Findings from the clinical study showed that reduction of blood lead levels (BLLs) between the end and initiation of therapy in the combined treatment group was significantly greater than that in the nutritional intervention group. Percentage of children with BLLs less than 10μg/dL at the end of therapy and the eighth week after therapy in the combined treatment group was significantly higher than that in the nutritional intervention group. In conclusion, combined use of succimer with calcium and ascorbic acid seemed to be a choice in the treatment of mildly lead poisoned children.

  14. Isolation and Identification of Alicyclobacillus with High Dipicolinic Acid and Heat Resistant Proteins from Mango Juice

    Directory of Open Access Journals (Sweden)

    Hamid Reza Akhbariyoon

    2016-10-01

    Full Text Available Background and Objectives: Microbial spoilage of juices and industries related with Alicyclobacillus are considerable international issues. This spore-forming bacterium causes changes in juices odor and taste. The isolation and identification of Alicyclobacillus contamination in juice producing and packaging industries has an essential role in the prevention and control of this type of spoilage bacterium in HACCP (Hazard analysis and critical control points manner.Materials and Methods: A thermo-acidophilic, non-pathogenic and sporeforming bacterium was isolated from mango juice. Preliminary identification of the isolates was based on morphological, biochemical and physiological properties. Identification at species level was made by PCR amplification. The influence of temperature in the range of 25-65°C in the growth of bacterium and in the range of 80-120°C in spore-resistant and heat resistant proteins was investigated and compared with other spore producing bacteria.Results and Conclusion: Phylogenetic analysis of the 16S rRNA gene sequencing indicated that the isolated strain constituted a distinct lineage in the Alicyclobacillus cluster and submitted to NCBI with access number Alicyclobacillus HRM-5 KM983424.1. The spores resisted 110°C for 3 h, and produced 28% dipicolinic acid more comparable to Bacillus licheniformis. Also they could produce 0.69 mg heat resistance protein after 1.5 h treatment in 100°C. The results showed that this strain could have biotechnological applications.Conflict of interests: The authors declare no conflict of interest.

  15. The oxidative degradation of barley β-glucan in the presence of ascorbic acid or hydrogen peroxide.

    Science.gov (United States)

    Mäkelä, Noora; Sontag-Strohm, Tuula; Maina, Ndegwa Henry

    2015-06-05

    Cereal β-glucans are polysaccharides with health benefits that have been linked to their ability to increase luminal viscosity. However, the functional properties of cereal β-glucans may be diminished by the susceptibility of this polysaccharide to oxidative degradation. In this study, barley β-glucan was oxidised with hydrogen peroxide or ascorbic acid and the oxidative degradation of β-glucan was investigated using both asymmetrical flow field-flow fractionation (AsFlFFF) with aqueous solvent and high performance size exclusion chromatography (HPSEC) with LiBr in DMSO as the solvent. Oxidation was shown to cause degradation of β-glucan, the reaction being faster when oxidised with hydrogen peroxide compared with ascorbic acid. Both HPSEC and AsFlFFF showed comparable results as long as aggregates (only observed in AsFlFFF) were not included in the integration. The compact aggregates observed in oxidised samples suggest oxidation driven interactions between β-glucan molecules.

  16. Conclusion on the peer review of the pesticide risk assessment of the active substance L-ascorbic acid

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2013-04-01

    Full Text Available The conclusions of the European Food Safety Authority (EFSA following the peer review of the initial risk assessments carried out by the competent authority of the rapporteur Member State the Netherlands, for the pesticide active substance L-ascorbic acid are reported. The context of the peer review was that required by Commission Regulation (EU No 188/2011. The conclusions were reached on the basis of the evaluation of the representative uses of L-ascorbic acid as a fungicide on potato, glasshouse tomato and field and glasshouse flower bulbs. The reliable endpoints concluded as being appropriate for use in regulatory risk assessment, derived from the available studies and literature in the dossier peer reviewed, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified.

  17. Investigation of Thermal Decomposition of Ascorbic Acid by TG-FTIR and Thermal Kinetics Analysis Shi Jingyan

    Institute of Scientific and Technical Information of China (English)

    史竞艳; LIU; Yuwen; WANG; Zhiyong; WANG; Cunxin

    2014-01-01

    The thermal behavior of dry solid ascorbic acid in nitrogen atmosphere in the temperature range of 25800℃was investigated by TG-FTIR.During the thermal decomposition process,five evolved gaseous species,including H2O,CO2,CO,CH4 and HCOOH,were identified and monitored,in which HCOOH was detected for the first time.The results indicated that ascorbic acid began to decompose at 191℃.Its decomposition process consisted of three stages,and dehydration and decarboxylation to form furfural were the possible principal mechanism.The kinetic analysis for the first decomposition stage was also carried out by the isoconversional method and the master plots method.The results indicated that this process can be described by the model of 1st order reaction.

  18. EFFECT OF ASCORBIC ACID ON DNA SYNTHESIS, INTRACELLULAR ACCUMULATION OF ADM AND ADM RESISTANCE OF TUMOR CELL LINES

    Institute of Scientific and Technical Information of China (English)

    Xie Zuofu; Lin Xiandong; Zhou Dongmei; Lin Sheng

    1998-01-01

    Objective: To determine the effect of ascorbic acid (AA) on DNA synthesis, intracellular accumulation of ADM and ADM resistance of tumor cell lines.Methods: K562, K562/ADM and KB cell lines were used to study the effect of ascorbic acid on DNA synthesis,intracellular accumulation of ADM and ADM resistance by fluid scintillometry, MTT method, spectrofluorophotometry and immunocytochemistry. Results: Results showed that AA was capable of inhibiting DNA synthesis of K562 and K562/ADM in a dose-dependence fashion,but not KB cell line, and significantly reducing ADM sensitivity in K562 and KB cell lines, as well as potentiating obviously ADM resistance in K562/ADM cell line. Conclusion: These effects of AA may be closely correlated with significant elevation of intracellular accumulation of ADM in KB cell line, and significant reduction of that in K562 and K562/ADM cell lines but possibly not correlated with the expression of Pglycoprotein.

  19. The content determination of calcium, magnesium and ascorbic acid in sea buckthorn fruits at vulcan coal dump

    Directory of Open Access Journals (Sweden)

    Andreea BRASOVAN

    2009-11-01

    Full Text Available The study presents data on content determination of calcium, magnesium and ascorbic acid in sea buckthorn fruits collected from Vulcan coal dump. The dump was never covered with soil or fertilizers containing azoth, potassium and phosphorus. The sea buckthorn was planted directly on the sterile and it has an important function in stabilizing the acclivity and fixing the atmospheric azoth with the nodosities on the roots. So, the sea buckthorn becomes widespread plant in coal dumps because it helps to the soil formation. The results obtained after the determination of calcium, magnesium and ascorbic acid from the fruits of this plant were compared with the values already reported in various references, concluding that these differences are insignificant (3.7% for magnesium and 9.4% for calcium. Therefore, the sea buckthorn from the dump can be used in food industry, as well as in pharmaceutics and medicine.

  20. Organic-inorganic hybrid materials based on polyaniline/TiO(2) nanocomposites for ascorbic acid fuel cell systems.

    Science.gov (United States)

    Ganesan, Raman; Gedanken, Aharon

    2008-10-29

    Polyaniline was grafted onto a mixture of rutile and anatase TiO(2) nanoparticles by in situ chemical oxidative polymerization. These nanocomposites were characterized by carbon, hydrogen and nitrogen (CHN) analysis, x-ray diffraction (XRD), Fourier transform infrared (FTIR), ultraviolet-visible (UV-vis), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis. FTIR and UV-vis confirm the formation of polyaniline on TiO(2) nanoparticles. The TEM shows that the composites consist of PANI and TiO(2) nanoparticles. Compared to the neat polyaniline, PANI/TiO(2) composites show a higher capacitance and also a higher activity per mass of polyaniline. Since the PANI/TiO(2) composites are stable during the electrooxidation of ascorbic acid, they can be used as an alternative catalyst for direct ascorbic acid fuel cells.

  1. Amperometric Determination of Ascorbic Acid in Pharmaceutical Formulations by a Reduced Graphene Oxide-cobalt Hexacyanoferrate Nanocomposite

    Science.gov (United States)

    Heli, Hossein

    2015-01-01

    Investigation of the redox properties of drugs and their determination are performed by electrochemical techniques. Data obtained from electrochemical techniques are often correlated with molecular structure and pharmacological activity of drugs. In this regard, different modified electrodes were applied as sensors for quantification of different drugs. A nanocomposite of reduced graphene oxide-cobalt hexacyanoferrate was synthesized by a simple precipitation route. Scanning electron microscopy revealed that the nanocomposite comprised nanoparticles of cobalt hexacyanoferrate attached to the reduced graphene oxide nanosheets. A nanocomposite-modified carbon paste electrode was then fabricated. It represented prominent activity toward the electrocatalytic oxidation of ascorbic acid, and the kinetics of the electrooxidation process was evaluated. Finally, an amperometric method was developed for the quantification of ascorbic acid in different pharmaceutical formulations. PMID:25901152

  2. Facile synthesis of graphene hybrid tube-like structure for simultaneous detection of ascorbic acid, dopamine, uric acid and tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Wen [Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Chai Yaqin, E-mail: yqchai@swu.edu.cn [Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Yuan Ruo, E-mail: yuanruo@swu.edu.cn [Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Chen Shihong; Han Jing; Yuan Dehua [Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China)

    2012-12-05

    Graphical abstract: A tube-like structure of graphene hybrid (GS-PTCA) was synthesized via {pi}-{pi} stacking interaction, and was used as modifier to fabricate electrode for simultaneous detection of ascorbic acid (AA), dopamine (DA), uric acid (UA) and tryptophan (Trp). SEM images of GS, PTCA and GS-PTCA were presented. Under the synergistic effects between GS and PTCA, the modified electrode displayed high catalytic activity and selectivity toward the oxidation of AA, DA, UA, and Trp. Highlights: Black-Right-Pointing-Pointer A simple strategy for simultaneous detection of AA, DA, UA and Trp has been constructed. Black-Right-Pointing-Pointer The tube-like structure of graphene hybrid (GS-PTCA) was synthesized. Black-Right-Pointing-Pointer The GS-PTCA provided a selective interface for discrimination of AA, DA, UA and Trp. - Abstract: In the present work, a tube-like structure of graphene hybrid as modifier to fabricate electrode for simultaneous detection of ascorbic acid (AA), dopamine (DA), uric acid (UA) and tryptophan (Trp) was reported. The hybrid was synthesized by a simple method based on graphene sheets (GS) and 3,4,9,10-perylenetetracarboxylic acid (PTCA) via {pi}-{pi} stacking interaction under ultrasonic condition. The combination of GS and PTCA could effectively improve the dispersion of GS, owing to PTCA with the carboxylic-functionalized interface. Comparing with pure GS or PTCA modified electrode, GS-PTCA displayed high catalytic activity and selectivity toward the oxidation of AA, DA, UA, and Trp. Moreover, cyclic voltammetry, different pulse voltammetry and scanning electron microscopy were employed to characterize the sensors. The experiment results showed that the linear response range for simultaneous detection of AA, DA, UA, and Trp were 20-420 {mu}M, 0.40-374 {mu}M, 4-544 {mu}M and 0.40-138 {mu}M, respectively, and the detection limits were 5.60 {mu}M, 0.13 {mu}M, 0.92 {mu}M and 0.06 {mu}M (S/N = 3). Importantly, the proposed method offers

  3. Synthesis of Au/Graphene Oxide Composites for Selective and Sensitive Electrochemical Detection of Ascorbic Acid

    Science.gov (United States)

    Song, Jian; Xu, Lin; Xing, Ruiqing; Li, Qingling; Zhou, Chunyang; Liu, Dali; Song, Hongwei

    2014-12-01

    In this work, we present a novel ascorbic acid (AA) sensor applied to the detection of AA in human sera and pharmaceuticals. A series of Au nanoparticles (NPs) and graphene oxide sheets (Au NP/GO) composites were successfully synthesized by reduction of gold (III) using sodium citrate. Then the Au NP/GO composites were used to construct nonenzymatic electrodes in practical AA measurement. The electrode that has the best performance presents attractive analytical features, such as a low working potential of +0.15 V, a high sensitivity of 101.86 μA mM-1 cm-2 to AA, a low detection limit of 100 nM, good reproducibility and excellent selectivity. And more,it was also employed to accurately and practically detect AA in human serum and clinical vitamin C tablet with the existence of some food additive. The enhanced AA electrochemical properties of the Au NP/GO modified electrode in our work can be attributed to the improvement of electroactive surface area of Au NPs and the synergistic effect from the combination of Au NPs and GO sheets. This work shows that the Au NP/GO/GCEs hold the prospect for sensitive and selective determination of AA in practical clinical application.

  4. Evidence for the safety of ascorbic acid administration to the premature infant.

    Science.gov (United States)

    Bass, W T; Malati, N; Castle, M C; White, L E

    1998-02-01

    Ascorbic acid (AA), a plasma antioxidant, is maintained at high levels in premature fetal blood and declines rapidly postpartum. The sudden reduction in blood AA levels secondary to premature delivery may increase the risk of oxidant injury, that is, bronchopulmonary dysplasia and intraventricular hemorrhage. There is concern that administration of AA to premature infants, in an effort to increase antioxidant capacity, may cause hemolysis. We felt that the benefits of early AA administration and prevention of the immediate postnatal drop in blood AA levels, might outweigh the risks of erthrocyte damage. Fifty one high-risk premature infants were randomized to receive either normal saline or 100 mg/kg of AA, daily for the first week of life. Double-blind comparisons were made of hemoglobin, hematocrit, erythrocyte morphology, bilirubin, number of blood transfusions and days of phototherapy, renal function tests, the incidence of infection, bronchopulmonary dysplasia, and intraventricular hemorrhage during the first month of life. The administration of AA prevented the immediate postnatal drop in AA and was not associated with evidence of increased hemolysis. No significant differences in renal function, rate of infection, bronchopulmonary dysplasia, or intraventricular hemorrhage were seen between the two groups. This study suggests that AA administration to the premature infant is safe and supports the designing and performance of larger clinical studies of the antioxidant properties of AA.

  5. D-penicillamine-templated copper nanoparticles via ascorbic acid reduction as a mercury ion sensor.

    Science.gov (United States)

    Lin, Shu Min; Geng, Shuo; Li, Na; Li, Nian Bing; Luo, Hong Qun

    2016-05-01

    Mercury ion is one of the most hazardous metal pollutants that can cause deleterious effects on human health and the environment even at low concentrations. It is necessary to develop new mercury detection methods with high sensitivity, specificity and rapidity. In this study, a novel and green strategy for synthesizing D-penicillamine-capped copper nanoparticles (DPA-CuNPs) was successfully established by a chemical reduction method, in which D-penicillamine and ascorbic acid were used as stabilizing agent and reducing agent, respectively. The as-prepared DPA-CuNPs showed strong red fluorescence and had a large Stoke's shift (270nm). Scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, fluorescence spectroscopy, and ultraviolet-visible spectrophotometry were utilized to elucidate the possible fluorescence mechanism, which could be aggregation-induced emission effect. Based on the phenomenon that trace mercury ion can disperse the aggregated DPA-CuNPs, resulting in great fluorescence quench of the system, a sensitive and selective assay for mercury ion in aqueous solution with the DPA-CuNPs was developed. Under optimum conditions, this assay can be applied to the quantification of Hg(2+) in the 1.0-30μM concentration range and the detection limit (3σ/slope) is 32nM. The method was successfully applied to determine Hg(2+) in real water samples.

  6. Ascorbic acid and BSA protein in solution and films: interaction and surface morphological structure.

    Science.gov (United States)

    Maciel, Rafael R G; de Almeida, Adriele A; Godinho, Odin G C; Gorza, Filipe D S; Pedro, Graciela C; Trescher, Tarquin F; Silva, Josmary R; de Souza, Nara C

    2013-01-01

    This paper reports on the study of the interactions between ascorbic acid (AA) and bovine serum albumin (BSA) in aqueous solution as well as in films (BSA/AA films) prepared by the layer-by-layer technique. Regarding to solution studies, a hyperchromism (in the range of ultraviolet) was found as a function of AA concentration, which suggested the formation of aggregates from AA and BSA. Binding constant, K, determined for aggregates from BSA and AA was found to be about 10(2) M(-1), which indicated low affinity of AA with BSA. For the BSA/AA films, it was also noted that the AA adsorption process and surface morphological structures depended on AA concentration. By changing the contact time between the AA and BSA, a hypochromism was revealed, which was associated to decrease of accessibility of solvent to tryptophan due to formation of aggregates. Furthermore, different morphological structures of aggregates were observed, which were attributed to the diffusion-limited aggregation. Since most of studies of interactions of drugs and proteins are performed in solution, the analysis of these processes by using films can be very valuable because this kind of system is able to employ several techniques of investigation in solid state.

  7. Transcriptomic analysis reveals the metabolic mechanism of L-ascorbic acid in Ziziphus jujuba Mill.

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    Chunmei eZhang

    2016-02-01

    Full Text Available Chinese jujube (Ziziphus jujuba Mill. is the most economically important member of the Rhamnaceae family and contains a high concentration of ascorbic acid (AsA. To explore the metabolic mechanism of AsA accumulation, we investigated the abundance of AsA in the fruit development stages, the leaf and flower of Z. jujuba cv Junzao, and the mature fruit of one type of wild jujube (Z. jujuba var. spinosa Hu, Yanchuan sour jujube. And the expression patterns of genes involved in AsA biosynthesis, degradation and recycling were analyzed. The result showed that AsA biosynthesis during early fruit development (the enlargement stage is the main reason for jujube high accumulation. The L-galactose pathway plays a predominant role in the biosynthesis of AsA during jujube fruit development, and the genes GMP1, GME1, GGP, and GaLDH involved in the determination of AsA concentration during fruit development and in different genotypes; the myo-inositol pathway along with the genes GME2 and GMP2 in the L-galactose pathway play a compensatory role in maintaining AsA accumulation during the ripening stage. These findings enhance our understanding of the molecular mechanism in regulating AsA accumulation for jujube.

  8. Effects of glucose and ascorbic acid on absorption and first pass metabolism of isoniazid in rats.

    Science.gov (United States)

    Matsuki, Y; Katakuse, Y; Matsuura, H; Kiwada, H; Goromaru, T

    1991-02-01

    We examined the effect of glucose (Glu) and ascorbic acid (AA) on absorption and metabolism of isoniazid (INAH). After p.o. administration of INAH with or without Glu or AA, plasma concentration and urinary excretion of INAH and its metabolites, acetyl INAH (AcINAH), acetyl hydrazine (AcHy) and hydrazine (Hy), were determined by means of gas chromatography-mass spectrometry using stable isotope labeled compounds as internal standard. The combined administration of INAH with Glu or AA led to a significant decrease in the excretion of INAH and Hy, and a significant increase in the excretion of AcINAH and AcHy. The absorption amount of INAH was reduced to about one-half by the addition of Glu and the absorption rate of INAH markedly decreased in the case of co-administration of AA. Comparing the oral case with the results of i.v. administration, Glu and AA only affect the absorption process containing the first pass metabolism of INAH.

  9. Excitability scores of goats administered ascorbic acid and transported during hot-dry conditions.

    Science.gov (United States)

    Ayo, J O; Minka, N S; Mamman, M

    2006-06-01

    In this study, we investigated the effect of ascorbic acid (AA) administration on goat excitability due to transportation. Ten goats administered AA (p.o.) at 100 mg/kg of body weight before transportation served as the experimental group, and seven goats administered only 10 ml/kg of sterile water (p.o.) served as controls. Excitability scores were recorded for each goat; when weighed, before, immediately after, and 3 h after 8 h of transportation. A score of one to four was allocated to each goat; higher scores represent greater excitability. Immediately after transportation, excitability scores decreased significantly, especially those of control goats (p 0.05) different from their pre-transportation normal values, whereas those of control goats were significantly lower (p < 0.01). The correlation i.e. the relationship between excitability score values and percent excitability (percentage of goat with particular excitability score) for different excitability score group 3 h post-transportation was positive and highly significant (p < 0.001), in both experimental and control goats. Our results indicate that road transportation induces considerable stress (depression) in goats as evidenced by a lower excitability score posttransportation. Moreover, the administration of AA pretransportation facilitated the transition from a state of depression to excitation. In conclusion, AA administration to animals prior to transportation may ameliorate the depression often encountered after road transportation.

  10. Application of tetra-isopalmitoyl ascorbic acid in cosmetic formulations: stability studies and in vivo efficacy.

    Science.gov (United States)

    Maia Campos, Patrícia M B G; Gianeti, Mirela D; Camargo, Flávio B; Gaspar, Lorena R

    2012-11-01

    Liposoluble vitamin C derivatives, such as tetra-isopalmitoyl ascorbic acid (IPAA), are often used in dermocosmetic products due to their higher stability than vitamin C free form as well as its proposed effects in skin; however, there are no studies analyzing IPAA stability or its in vivo effects when present in dermocosmetic formulations. Thus, this study aimed to evaluate chemical stability and pre-clinical and clinical efficacy of dermocosmetic formulations containing IPAA in skin hydration and microrelief. Chemical stability of the formulations added with 1% IPAA was evaluated by heat stress during 35 days by HPLC. For pre-clinical evaluation, experimental formulations were topically applied on hairless skin mice during 5 days and animal skins were analyzed by non-invasive biophysic techniques (water content of stratum corneum, TEWL, viscoelasticity, and microrelief) and by histopathological studies. For clinical efficacy tests, the formulations were topically applied to the forearm and face of human volunteers, and 3h and 15 days after applications, the skins were evaluated by the same non-invasive techniques mentioned before. Results showed that formulations containing IPAA had medium stability and had pronounced moisturizing effects on stratum corneum and on viable epidermis. These formulations also improved skin microrelief especially in relation to skin smoothness and roughness.

  11. Ascorbic acid: its role in immune system and chronic inflammation diseases.

    Science.gov (United States)

    Sorice, Angela; Guerriero, Eliana; Capone, Francesca; Colonna, Giovanni; Castello, Giuseppe; Costantini, Susan

    2014-05-01

    Ascorbic acid (AA), also known as vitamin C, was initially identified as the factor preventing the scurvy disease, and became very popular for its antioxidant properties. It is an important co-substrate of a large class of enzymes, and regulates gene expression by interacting with important transcription factors. AA is important in all stressful conditions that are linked to inflammatory processes and involve immunity. It has been known for decades that the persistence of an inflammatory stimulus is responsible for the onset of many diseases. AA is essential to stimulate the immune system by increasing the strength and protection of the organism. Therefore, its immunostimulant, antinflammatory, antiviral and antibacterial roles are well known, we have summarized its main functions in different types of diseases related to the immune system and chronic inflammation. We can conclude that AA, due to its effects and diversity of regulated pathways, is suitable for use in various fields of medicine including immunology, toxicology, radiobiology and others. AA is not preferable to be used as an isolated mode of treatment, but it can be co-applied as an adjuvant to regulate immunity, gene expression and other important physiological processes. However, we propose that future studies will take into consideration the research of new combinations of antioxidant natural substances and drugs.

  12. Action of ascorbic acid on the healing of malnourished rats'skin wounds

    Directory of Open Access Journals (Sweden)

    Gisele Alborghetti Nai

    2014-08-01

    Full Text Available Objective: To evaluate the action of ascorbic acid on the healing of malnourished rats' cutaneous wounds compared with normal weight rats. Methods: We used 92 adult, male Wistar rats divided into four groups: 24 normal weight rats given only water and chow; 24 normal weight rats given vitamin C by gavage (340 mg/kg 12/12 hours; 22 malnourished rats given only water and chow; and 22 malnourished rats given vitamin C by gavage (340 mg/kg 12/12 hours. Malnutrition was induced by feeding the animals half of their daily energy requirement for 30 days. Two incisions were made, one sutured (healing by primary intention and one left unsutured (healing by secondary intention. The rats were euthanized on the third, seventh, and fourteenth days of the experiment. Results: The following parameters differed significantly between the groups (p>0.05: granulation of the wound edge in the primary and secondary intention; extent of injuries on day 7 for primary intention and on day 3 for secondary intention; reepithelialization on day 7 for primary intention; fibrin-leukocyte scab on day 14 for primary intention; amount of neovascularization and concentration of macrophages, fibroblasts, and collagen fibers for primary and secondary intention. Conclusion: The use of vitamin C in malnourished and normal weight rats increases fibroblast proliferation and collagen deposition in the tissue, which helps to improve healing both by primary and secondary intention.

  13. Direct Determination of Ascorbic Acid in a Grapefruit: Paving the Way for In Vivo Spectroelectrochemistry.

    Science.gov (United States)

    Garoz-Ruiz, Jesus; Heras, Aranzazu; Colina, Alvaro

    2017-02-07

    The study of real samples is more complicated than the study of other systems. However, the inherent advantages of UV-vis absorption spectroelectrochemistry should overcome some difficulties related to direct measurements in complex matrices. For this reason, a singular spectroelectrochemistry device has been fabricated and validated. The novel cell is based on single-walled carbon nanotubes, which are filtered and subsequently press-transferred on a polyethylene terephthalate support using a stencil with a custom design. With this new methodology, working, counter, and reference electrodes are completely flat on the surface, where two optical fibers are fixed in a long optical path length configuration. To demonstrate the usefulness of this device and the power of spectroelectrochemistry techniques to solve problems of the current world, this device is used to quantitatively detect the concentration of ascorbic acid in a complex matrix such as a fruit, directly, without any previous sample pretreatment. The ease to fabricate the device, the advantages related to its use, and the excellent results obtained not only with univariate but also with multivariate analysis, shed more light on the analysis of samples as they occur in nature. According to the particular features of this cell, to the best of our knowledge this is the first spectroelectrochemical sensor that can be inserted directly in a biological matrix, laying the groundwork to perform in vivo measurements in a near future.

  14. Polyethyleneimine-templated copper nanoclusters via ascorbic acid reduction approach as ferric ion sensor

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Jie; Ju, Yuyun; Liu, Juanjuan; Zhang, Huige [State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000 (China); Department of Chemistry, Lanzhou University, Lanzhou 730000 (China); Chen, Xingguo, E-mail: chenxg@lzu.edu.cn [State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000 (China); Department of Chemistry, Lanzhou University, Lanzhou 730000 (China); Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, Lanzhou 730000 (China)

    2015-01-07

    Highlights: • A new method for synthesis of the BPEI-CuNCs is established. • A facile approach for Fe{sup 3+} ion sensing by fluorescence quenching is developed. • The method for Fe{sup 3+} sensing has high sensitivity and excellent selectivity. - Abstract: In this report we reported a facile one-pot method for synthesis of water-soluble and stable fluorescent CuNCs at room temperature, in which branched polyethyleneimine (BPEI) served as capping scaffold and ascorbic acid as reducing agent. The prepared BPEI-CuNCs exhibited excellent properties such as good water-solubility, photostability and high stability toward high ionic strength. Based on the electron transfer induced fluorescence quenching mechanism, this fluorescence probe was used for the sensitive and selective determination of ferric ions (Fe{sup 3+}) in aqueous solution. The limit of detection was 340 nM in the linear range of 0.5–1000 μM, which was lower than the maximum level of Fe{sup 3+} permitted in drinking water by the U.S. Environmental Protection Agency. The method was successfully applied to the detection of Fe{sup 3+} in tap water, Yellow River water and human urine samples with the quantitative spike recoveries ranging from 95.3% to 112.0%.

  15. Ascorbic acid decreases morphine self-administration and withdrawal symptoms in rats.

    Science.gov (United States)

    Alaei, H; Esmaeili, M; Nasimi, A; Pourshanazari, A

    2005-09-01

    Recent studies have indicated that the glutamatergic system is involved in the motivational aspects during the initiation of drug self-administration. Ascorbic acid (AA), an antioxidant vitamin, is released from glutamatergic neurons, and it modulates the synaptic action of dopamine and glutamate. In this study the AA effects on the self-administration of morphine and on the morphine withdrawal syndrome have been investigated. Wistar rats were allowed to self-administer morphine (1 mg/infusion) during 10 consecutive days for 2 h/session. The number of lever pressings was recorded. An intrapritoneal AA injection (500 mg/kg, i.p.), 30 min before morphine self-administration produced a significant decrease in the initiation of morphine self administration during all sessions. After the last test session morphine withdrawal symptom signs (MWS) were recorded after naloxone precipitation. Most of MWS (but not all) were decreased by AA application. In conclusion, AA may change the motivational processes underlying the morphine self-administration.

  16. Histological evaluation of the periodontal ligament from aged wistar rats supplemented with ascorbic acid

    Directory of Open Access Journals (Sweden)

    Jacqueline N. Zanoni

    2013-03-01

    Full Text Available Ascorbic acid (AA is able to neutralize reactive oxygen species and is essential for collagen synthesis. In aging process oxidative stress is elevated. This study aims to investigate the effects of AA supplementation on the periodontal ligament (PL of rats during aging. Twenty five rats were used and divided into groups: J90 (90-day-old control, E345 (345-day-old control, E428 (428-day-old control, EA345 (345-day-old supplemented with AA from 90-day-old on and EA428 (428-day-old supplemented with AA from 90-day-old on. We analyzed the thickness, density of fibroblasts and blood vessels and collagen fibers types in the PL. In group J90 there was predominantly type III collagen fibers (87.64%. In animals supplemented with AA, the area filled by type I fibers (group EA345: 65.67%, group EA428: 52.23% was higher than type III fibers. PL in group EA428 was thicker than the one observed in group E428 (P < 0.05. During natural aging process, AA promoted the maturation of collagen fibers and enhanced angiogenesis in periodontal ligament. One can conclude that the supplementation with AA represented a beneficial factor for the development of PL in aged rats.

  17. Impact of exogenous ascorbic acid on biochemical activities of rice callus treated with salt stress

    Science.gov (United States)

    Alhasnawi, Arshad Naji; Zain, Che Radziah Che Mohd; Kadhimi, Ahsan A.; Isahak, Anizan; Mohamad, Azhar; Ashraf, Mehdi Farshad; Doni, Febri; Yusoff, Wan Mohtar Wan

    2016-11-01

    The application of in vitro systems can lead to new methods of crop amelioration. This method has been widely utilized for breeding tenacities, particularly for stress tolerance selection. Salinity causes oxidative stress in callus by enhancing the production of Reactive Oxygen Species (ROS), resulting in an efficient antioxidant system. The exogenous application of ascorbic acid (AsA) is an important requirement for tolerance. The present study aimed to examine in vitro selection strategy for callus induction in rice mature embryo culture on MS culture medium and to produce salt-tolerant callus under sodium chloride (NaCl) and AsA conditions in callus rice variety, MR269. This study also highlights changes in the activities of proline and antioxidants peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) of callus under NaCl stress to understand their possible role in salt tolerance. However, various levels of exogenously applied AsA under saline conditions improved callus, and the antioxidant enzyme activities of AsA are related to resistance to oxidative stress. Our results provide strong support for the hypothesis that AsA-dependent antioxidant enzymes play a significant role in the salinity tolerance of callus rice.

  18. Nitrogen doped graphene quantum dots based long-persistent chemiluminescence system for ascorbic acid imaging.

    Science.gov (United States)

    Chen, Hongjun; Wang, Qin; Shen, Qinpeng; Liu, Xin; Li, Wang; Nie, Zhou; Yao, Shouzhuo

    2017-05-15

    High photo-intensity and sluggish flight attenuation are important to highly sensitive chemluminescence imaging. Herein, we present a copper ion catalyzed long-persistent chemiluminescent imaging system of nitrogen-doped graphene quantum dots (NGQDs) for ascorbic acid detection in fruit. NGQDs as luminescent probe are fabricated, emitting out chemluminescence with the direct oxidation by H2O2. In addition, Cu(2+) ion enlarges over two order magnitudes of NGQDs CL intensity (214 times) due to its catalyzed Fenton-like reaction for H2O2 decomposition, and displaying unique specificity against other metal ions. As a result, the twinkling luminescence of NGQDs is boosted and changes to hold persistent with small decay in the presence of copper ion exhibiting potential for CL imaging. As an imaging model, a visual sensor based on Cu(2+)/NGQDs/H2O2 is developed for AA quantitative monitoring with a limit of detection (LOD) of 0.5μM (S/N=3) and applied in real AA detection in fruit. The CL imaging method demonstrated with high stability and proper sensitivity would provide a convenient and visual tool for AA determination, displaying promising candidates for imaging sensing. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Preparation of monodisperse aqueous microspheres containing high concentration of l-ascorbic acid by microchannel emulsification.

    Science.gov (United States)

    Khalid, Nauman; Kobayashi, Isao; Neves, Marcos A; Uemura, Kunihiko; Nakajima, Mitsutoshi; Nabetani, Hiroshi

    2015-01-01

    Monodisperse aqueous microspheres containing high concentrations of l-ascorbic acid with different concentrations of sodium alginate (Na-ALG) and magnesium sulfate (MgSO4) were prepared by using microchannel emulsification (MCE). The continuous phase was water-saturated decane containing a 5% (w/w) hydrophobic emulsifier. The flow rate of the continuous phase was maintained at 10 mL h(-1), whereas the pressure applied to the disperse phase was varied between 3 and 25 kPa. The disperse phase optimized for successfully generating aqueous microspheres included 2% (w/w) Na-ALG and 1% (w/w) MgSO4. At a higher MgSO4 concentration, the generated microspheres resulted in coalescence and subsequent bursting. At a lower MgSO4 concentration, unstable and polydisperse microspheres were obtained. The aqueous microspheres generated from the MCs under optimized conditions had a mean particle diameter (dav) of 14-16 µm and a coefficient of variation (CV) of less than 8% at the disperse phase pressures of 5-15 kPa.

  20. Sparing effects of selenium and ascorbic acid on vitamin C and E in guinea pig tissues

    Directory of Open Access Journals (Sweden)

    Hayward Stephen

    2007-03-01

    Full Text Available Abstract Background Selenium (Se, vitamin C and vitamin E function as antioxidants within the body. In this study, we investigated the effects of reduced dietary Se and L-ascorbic acid (AA on vitamin C and α-tocopherol (AT status in guinea pig tissues. Methods Male Hartley guinea pigs were orally dosed with a marginal amount of AA and fed a diet deficient (Se-D/MC, marginal (Se-M/MC or normal (Se-N/MC in Se. An additional diet group (Se-N/NC was fed normal Se and dosed with a normal amount of AA. Guinea pigs were killed after 5 or 12 weeks on the experimental diets at 24 and 48 hours post AA dosing. Results Liver Se-dependent glutathione peroxidase activity was decreased (P P > 0.05 by reduction in dietary Se or AA. All tissues examined showed a decrease (P P P Conclusion Together, these data demonstrate sparing effects of Se and AA on vitamin C and AT in guinea pig tissues.

  1. Triethylenetetramine Synergizes with Pharmacologic Ascorbic Acid in Hydrogen Peroxide Mediated Selective Toxicity to Breast Cancer Cell

    Science.gov (United States)

    Wang, Lianlian; Luo, Xiaofang; Li, Cong; Huang, Yubing; Xu, Ping; Lloyd-Davies, Laetitia H.; Delplancke, Thibaut; Peng, Chuan; Qi, Hongbo; Baker, Philip

    2017-01-01

    Breast cancer is characterized by overexpression of superoxide dismutase (SOD) and downregulation of catalase and more resistance to hydrogen peroxide (H2O2) than normal cells. Thus, relatively high H2O2 promotes breast cancer cell growth and proliferation. However, excessive intracellular H2O2 leads to death of breast cancer cells. In cancer cells, high level ascorbic acid (Asc) is able to be autoxidized and thus provides an electron to oxygen to generate H2O2. In the present study, we demonstrated that triethylenetetramine (TETA) enhances Asc autoxidation and thus elevates H2O2 production in MCF-7 cells. Furthermore, Asc/TETA combination significantly impaired cancer cell viability, while having much milder effects on normal cells, indicating Asc/TETA could be a promising therapy for breast cancer. Moreover, SOD1 and N-acetyl-L-cysteine failed to improve MCF-7 cells viability in the presence of Asc/TETA, while catalase significantly inhibited the cytotoxicity of Asc/TETA to breast cancer cells, strongly suggesting that the selective cytotoxicity of Asc/TETA to cancer cells is H2O2-dependent. In addition, Asc/TETA induces RAS/ERK downregulation in breast cancer cells. Animal studies confirmed that Asc/TETA effectively suppressed tumor growth in vivo. In conclusion, TETA synergizes pharmacologic Asc autoxidation and H2O2 overproduction in breast cancer cells, which suppresses RAS/ERK pathway and results in apoptosis.

  2. Electrochemical Molecular Imprinted Sensors Based on Electrospun Nanofiber and Determination of Ascorbic Acid.

    Science.gov (United States)

    Zhai, Yunyun; Wang, Dandan; Liu, Haiqing; Zeng, Yanbo; Yin, Zhengzhi; Li, Lei

    2015-01-01

    In this study, electrochemical molecularly imprinted sensors were fabricated and used for the determination of ascorbic acid (AA). Nanofiber membranes of cellulose acetate (CA)/multi-walled carbon nanotubes (MWCNTs)/polyvinylpyrrolidone (PVP) (CA/MWCNTs/PVP) were prepared by electrospinning technique. After being transferred to a glass carbon electrode (GC), the nanofiber interface was further polymerized with pyrrole through electrochemical cyclic voltammetry (CV) technique. Meanwhile, target molecules (such as AA) were embedded into the polypyrrole through the hydrogen bond. The effects of monomer concentration (pyrrole), the number of scan cycles and scan rates of polymerization were optimized. Differential pulse voltammetry (DPV) tests indicated that the oxidation current of AA (the selected target) were higher than that of the structural analogues, which illustrated the selective recognition of AA by molecularly imprinted sensors. Simultaneously, the molecularly imprinted sensors had larger oxidation current of AA than non-imprinted sensors in the processes of rebinding. The electrochemical measurements showed that the molecularly imprinted sensors demonstrated good identification behavior for the detection of AA with a linear range of 10.0 - 1000 μM, a low detection limit down to 3 μM (S/N = 3), and a recovery rate range from 94.0 to 108.8%. Therefore, the electrochemical molecularly imprinted sensors can be used for the recognition and detection of AA without any time-consuming elution. The method presented here demonstrates the great potential for electrospun nanofibers and MWCNTs to construct electrochemical sensors.

  3. Determination of L-ascorbic acid in Lycopersicon fruits by capillary zone electrophoresis.

    Science.gov (United States)

    Galiana-Balaguer, L; Roselló, S; Herrero-Martínez, J M; Maquieira, A; Nuez, F

    2001-09-15

    This study shows an improved method for the determination of L-ascorbic acid (l-AA) in fruits of Lycopersicon by capillary zone electrophoresis (CZE). Two backgrounds electrolytes (BGEs) have been tested: (i) 400 mM borate at pH 8.0 and 1 x 10(-2)% hexadimethrine bromide, for the separation of Eulycopersicon subgenus species; and (ii) as in BGE(i) but supplemented with 20% (v/v) acetonitrile, for the separation of species of the Eriopersicon subgenus. The present procedures were compared with two routine methods-enzymatic assay and potentiometric titration with 2,6-dichlorophenol-indophenol. While these routine methods presented some difficulties in quantifying l-AA in several Lycopersicon fruits, CZE was successfully applied in all the analyzed samples. The proposed CZE protocols give lower detection limits (<0.4 microg ml(-1)); are cheaper, quicker, and highly reproducible; and can be applied to analyze large series of samples (ca. 50 samples per day) which is utmost importance, not only in screening trials for internal quality and tomato breeding programs, but also in systematic and routine characterization of Lycopersicon fruits.

  4. 3D graphene foams decorated by CuO nanoflowers for ultrasensitive ascorbic acid detection.

    Science.gov (United States)

    Ma, Ye; Zhao, Minggang; Cai, Bin; Wang, Wei; Ye, Zhizhen; Huang, Jingyun

    2014-09-15

    When the in vitro research works of biosensing begin to mimic in vivo conditions, some certain three-dimensional (3D) structures of biosensors are needed to accommodate biomolecules, bacteria or even cells to resemble the in vivo 3D environment. To meet this end, a novel method of synthesizing CuO nanoflowers on the 3D graphene foam (GF) was first demonstrated. The 3DGF/CuO nanoflowers composite was used as a monolithic free-standing 3D biosensor for electrochemical detection of ascorbic acid (AA). The 3D conductive structure of the GF is favorable for current collection, mass transport and loading bioactive chemicals. And CuO nanoflowers further increase the active surface area and catalyze the redox of AA. Thus, all these features endows 3DGF/CuO composite with outstanding biosensing properties such as an ultrahigh sensitivity of 2.06 mA mM(-1) cm(-2) to AA at 3 s response time.

  5. Electrochemical determination of ascorbic acid at p-phenylenediamine film-holes modified glassy carbon electrode

    Directory of Open Access Journals (Sweden)

    Olana Bikila Nagasa

    2015-01-01

    Full Text Available In this work the determination of ascorbic acid (AA at glassy carbon electrode (GCE modified with a perforated film produced by reduction of diazonium generated in situ from p-phenylenediamine (PD is reported. Holes were intentionally created in the modifier film by stripping a pre-deposited gold nanoparticles. The modified electrodes were electrochemically characterized by common redox probes: hydroquinone, ferrocyanide and hexamineruthenium(III. The cyclic voltammetric and amperometric response of AA using the modified electrodes was compared with that of bare GCE. The bare GCE showed a linear response to AA in the concentration range of 5 mM to 45 mM with detection limit of 1.656 mM and the modified GCE showed a linear response to AA in the concentration range of 5 μM to 45 μM with detection limit of 0.123 μM. The effect of potential intereferents on amperometric signal of AA at the modified GCE was examined and found to be minimal. The inter-electrode reproducibility, stability, and accuracy were determined. The modified electrode showed excellent inter-electrode reproducibility, accuracy and stability. The modified electrode reported is a promising candidate for use in electroanalysis of AA.

  6. Polyoxometalate-Graphene Nanocomposite Modified Electrode for Electrocatalytic Detection of Ascorbic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Weiying; Du, Dan; Gunaratne, Don; Colby, Robert; Lin, Yuehe; Laskin, Julia

    2013-11-15

    Phosphomolybdate functionalized graphene nanocomposite (PMo12-GS) has been successfully formed on a glassy carbon electrode (GCE) for the detection of ascorbic acid (AA). The obtained PMo12-GS modified GCE, was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy and compared with GCE, GS modified GCE, and PMo12 modified GCE. It shows an increased current and a decrease in over-potential of ~210 mV. The amperometric signals are linearly proportional to the AA concentration in a wide concentration range from 1×10-6 M to 8×10-3 M, with a detection limit of 0.5×10-6 M. Finally, the PMo12-GS modified electrode was employed for the determination of the AA level in vitamin C tablets, with recoveries between 96.3 and 100.8 %.

  7. Simultaneous Chronoamperometric Sensing of Ascorbic Acid and Acetaminophen at a Boron-Doped Diamond Electrode

    Directory of Open Access Journals (Sweden)

    Ciprian Radovan

    2008-06-01

    Full Text Available Cyclic voltammetry (CV and chronoamperometry (CA have been used to sense and determine simultaneously L-ascorbic acid (AA and acetaminophen (AC at a boron-doped diamond electrode (BDDE in a Britton-Robinson buffer solution. The calibration plots of anodic current peak versus concentration obtained from CV and CA data for both investigated compounds in single and di-component solutions over the concentration range 0.01 mM – 0.1 mM proved to be linear, with very good correlation parameters. Sensitivity values and RSD of 2-3% were obtained for various situations, involving both individual and simultaneous presence of AA and AC. The chronoamperometric technique associated with standard addition in sequential one step and/or two successive and continuous chronoamperograms at two characteristic potential levels represented a feasible option for the simultaneous determination of AA and AC in real sample systems such as pharmaceutical formulations. The average values indicated by the supplier were confirmed to a very close approximation from chronoamperomgrams by using several additions with the application of suitable current correction factors.

  8. Daytime of Sampling, Tooth-Brushing and Ascorbic Acid Influence Salivary Thiobarbituric Acid Reacting Substances – A Potential Clinical Marker of Gingival Status

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    Július Hodosy

    2005-01-01

    Sialic acid content of saliva is not influenced significantly by any of the investigated factors. Conclusion. TBARS levels in saliva are affected by daytime of sampling, tooth-brushing and ascorbic acid pre-treatment. These results must be considered in clinical research using salivary TBARS levels. Sialic acid seems not to be a major component of TBARS in saliva. Further studies should clarify the molecular compounds of salivary TBARS and uncover the role of oral microbial factors.

  9. A miniature glucose/O{sub 2} biofuel cell with a high tolerance against ascorbic acid

    Energy Technology Data Exchange (ETDEWEB)

    Li, X.; Zhang, L. [Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing (China); Graduate School of CAS, Beijing (China); Su, L. [Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing (China); Ohsaka, T. [Department of Electronic Chemistry, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Midori-ku, Yokohama (Japan); Mao, L.

    2009-02-15

    This study demonstrates a miniature glucose/O{sub 2} biofuel cell (BFC) with a high tolerance against physiological level of ascorbic acid (AA) by immobilising ascorbate oxidase (AAox) on both the bioanode and the biocathode. Single-walled carbon nanotube (SWNT)-modified carbon fiber microelectrodes (CFMEs) are employed as the substrate electrode for the bioanode and biocathode. Glucose dehydrogenase (GDH) and bilirubin oxidase (BOD) are used as the biocatalysts for the electro-oxidation of glucose and for the electro-reduction of oxygen, respectively. SWNTs are used as the support for the both, stably confining the electrocatalyst (i.e. polymerised methylene blue, polyMB) for the oxidation of NADH co-factor for GDH and efficiently facilitating direct electrochemistry of the cathodic biocatalyst (i.e. BOD) for O{sub 2} reduction. The prepared micro-sized GDH-based bioanode and BOD-based biocathode employed for the bioelectrocatalytic oxidation of glucose and reduction of oxygen, respectively, are further over-coated with AAox to give a miniature glucose/O{sub 2} BFC with a high tolerance against AA. The maximum power density and the open circuit voltage (OCV) of the assembled glucose/O{sub 2} BFC are 52 {mu}W cm{sup -2} and 0.60 V, respectively. These values remain unchanged with the presence of AA in solution. In the human serum containing 10 mM NAD{sup +} and under ambient air, the maximum power density and the OCV of the assembled glucose/O{sub 2} BFC with AAox immobilisation on both the bioanode and the biocathode are 35 {mu}W cm{sup -2} and 0.39 V, respectively. These values are remarkably larger than those of the glucose/O{sub 2} BFC without AAox immobilisation on both the bioanode and the biocathode. This study could offer a new route to the development of enzymatic BFCs with promising application in real biological systems. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  10. Transcriptome Profiling of Tomato Fruit Development Reveals Transcription Factors Associated with Ascorbic Acid, Carotenoid and Flavonoid Biosynthesis.

    Science.gov (United States)

    Ye, Jie; Hu, Tixu; Yang, Congmei; Li, Hanxia; Yang, Mingze; Ijaz, Raina; Ye, Zhibiao; Zhang, Yuyang

    2015-01-01

    Tomato (Solanum lycopersicum) serves as a research model for fruit development; however, while it is an important dietary source of antioxidant nutrients, the transcriptional regulation of genes that determine nutrient levels remains poorly understood. Here, the transcriptomes of fruit at seven developmental stages (7, 14, 21, 28, 35, 42 and 49 days after flowering) from two tomato cultivars (Ailsa Craig and HG6-61) were evaluated using the Illumina sequencing platform. A total of 26,397 genes, which were expressed in at least one developmental stage, were detected in the two cultivars, and the expression patterns of those genes could be divided into 20 groups using a K-mean cluster analysis. Gene Ontology term enrichment analysis indicated that genes involved in RNA regulation, secondary metabolism, hormone metabolism and cell wall metabolism were the most highly differentially expressed genes during fruit development and ripening. A co-expression analysis revealed several transcription factors whose expression patterns correlated with those of genes associated with ascorbic acid, carotenoid and flavonoid biosynthesis. This transcriptional correlation was confirmed by agroinfiltration mediated transient expression, which showed that most of the enzymatic genes in the ascorbic acid biosynthesis were regulated by the overexpression of each of the three transcription factors that were tested. The metabolic dynamics of ascorbic acid, carotenoid and flavonoid were investigated during fruit development and ripening, and some selected transcription factors showed transcriptional correlation with the accumulation of ascorbic acid, carotenoid and flavonoid. This transcriptome study provides insight into the regulatory mechanism of fruit development and presents candidate transcription factors involved in secondary metabolism.

  11. Transcriptome Profiling of Tomato Fruit Development Reveals Transcription Factors Associated with Ascorbic Acid, Carotenoid and Flavonoid Biosynthesis.

    Directory of Open Access Journals (Sweden)

    Jie Ye

    Full Text Available Tomato (Solanum lycopersicum serves as a research model for fruit development; however, while it is an important dietary source of antioxidant nutrients, the transcriptional regulation of genes that determine nutrient levels remains poorly understood. Here, the transcriptomes of fruit at seven developmental stages (7, 14, 21, 28, 35, 42 and 49 days after flowering from two tomato cultivars (Ailsa Craig and HG6-61 were evaluated using the Illumina sequencing platform. A total of 26,397 genes, which were expressed in at least one developmental stage, were detected in the two cultivars, and the expression patterns of those genes could be divided into 20 groups using a K-mean cluster analysis. Gene Ontology term enrichment analysis indicated that genes involved in RNA regulation, secondary metabolism, hormone metabolism and cell wall metabolism were the most highly differentially expressed genes during fruit development and ripening. A co-expression analysis revealed several transcription factors whose expression patterns correlated with those of genes associated with ascorbic acid, carotenoid and flavonoid biosynthesis. This transcriptional correlation was confirmed by agroinfiltration mediated transient expression, which showed that most of the enzymatic genes in the ascorbic acid biosynthesis were regulated by the overexpression of each of the three transcription factors that were tested. The metabolic dynamics of ascorbic acid, carotenoid and flavonoid were investigated during fruit development and ripening, and some selected transcription factors showed transcriptional correlation with the accumulation of ascorbic acid, carotenoid and flavonoid. This transcriptome study provides insight into the regulatory mechanism of fruit development and presents candidate transcription factors involved in secondary metabolism.

  12. Haematological and immune upshots in Clarias batrachus exposed to dimethoate and defying response of dietary ascorbic acid.

    Science.gov (United States)

    Narra, Madhusudan Reddy

    2017-02-01

    Dimethoate (DM) is an organophosphate insecticide used worldwide in agriculture, household practices. It has resulted in a series of environmental and toxicological impacts on non-target aquatic organisms. The present study investigated the potential ameliorative effects of dietary ascorbic acid (AA) against dimethoate toxicity in the haematological and immune parameters in Clarias batrachus. The experiment included group A (basal diet), group B (basal diet with 1.245 mg L(-1) DM) and group C (200 mg kg(-1) AA with 1.245 mg L(-1) DM) were fed for 8 weeks. Samples were collected at the end of every week in each group and estimated haematological profile (red blood cell count, haemoglobin concentration, haematocrit %, albumin and globulin levels), erythrocyte indices (mean corpuscular volume, mean corpuscular haemoglobin, and mean corpuscular haemoglobin concentration), biochemical parameters (AA levels in blood and liver, total proteins, glucose, serum triglycerides, creatinine levels and glutamic oxaloacetate, glutamic pyruvate transaminase (GOT, GPT)) and immune responses (white blood cell count, serum IgM levels and activities of nitroblue tetrazolium, lysozyme and peroxidase) of the fish. Fish fed with ascorbic acid, showed red blood cell, haemoglobin, haematocrit, erythrocyte indices, albumin, globulin and serum triglycerides, creatinine, plasma total proteins, glucose levels are not differed (≤10%) from control. Likewise, ascorbic acid maintains optimal levels in activities of GOT, GPT, nitroblue tetrazolium, lysozyme and peroxidase, white blood cells and serum IgM levels. Further studies are needed to ascertain how ascorbic acid improves the innate and humoral immune system of the fish and the mechanisms involved.

  13. Phenolic compounds, organic acids and antioxidant activity of grape juices produced in industrial scale by different processes of maceration.

    Science.gov (United States)

    Lima, Marcos dos Santos; da Conceição Prudêncio Dutra, Maria; Toaldo, Isabela Maia; Corrêa, Luiz Claudio; Pereira, Giuliano Elias; de Oliveira, Débora; Bordignon-Luiz, Marilde Terezinha; Ninow, Jorge Luiz

    2015-12-01

    The effect of maceration process on the profile of phenolic compounds, organic acids composition and antioxidant activity of grape juices from new varieties of Vitis labrusca L. obtained in industrial scale was investigated. The extraction process presented a high yield without pressing the grapes. The use of a commercial pectinase resulted in an increase on extraction yield and procyanidins B1 and B2 concentrations and a decrease on turbidity and concentration of catechins. The combination of 60 °C and 3.0 mL 100 kg(-1) of enzyme resulted in the highest extraction of phenolic compounds, reducing the content of acetic acid. The juices presented high antioxidant activity, related to the great concentration of malvidin, cyanidin, catechin and