Metabolic Conversion of l-Ascorbic Acid to Oxalic Acid in Oxalate-accumulating Plants 1

PubMed Central

Yang, Joan C.; Loewus, Frank A.

1975-01-01

l-Ascorbic acid-1-14C and its oxidation product, dehydro-l-ascorbic acid, produced labeled oxalic acid in oxalate-accumulating plants such as spinach seedlings (Spinacia oleracea) and the detached leaves of woodsorrel (Oxalis stricta and O. oregana), shamrock (Oxalis adenopylla), and begonia (Begonia evansiana). In O. oregana, conversion occurred equally well in the presence or absence of light. This relationship between l-ascorbic acid metabolism and oxalic acid formation must be given careful consideration in attempts to explain oxalic accumulation in plants. PMID:16659288

Marginal Ascorbate Status (Hypovitaminosis C) Results in an Attenuated Response to Vitamin C Supplementation.

PubMed

Carr, Anitra C; Pullar, Juliet M; Bozonet, Stephanie M; Vissers, Margreet C M

2016-06-03

Inadequate dietary intake of vitamin C results in hypovitaminosis C, defined as a plasma ascorbate concentration ≤23 μmol/L. Our objective was to carry out a retrospective analysis of two vitamin C supplementation studies to determine whether supplementation with 50 mg/day vitamin C is sufficient to restore adequate ascorbate status (≥50 μmol/L) in individuals with hypovitaminosis C. Plasma ascorbate data from 70 young adult males, supplemented with 50 or 200 mg/day vitamin C for up to six weeks, was analyzed. Hypovitaminosis C status was identified based on plasma ascorbate being ≤23 μmol/L and the response of these individuals to vitamin C supplementation was examined. Of the participants consuming 50 mg/day vitamin C for up to six weeks, those with hypovitaminosis C at baseline achieved plasma concentrations of only ~30 μmol/L, whereas the remainder reached ~50 μmol/L. Participants who consumed 200 mg/day vitamin C typically reached saturating concentrations (>65 μmol/L) within one week, while those with hypovitaminosis C required two weeks to reach saturation. Regression modelling indicated that the participants' initial ascorbate status and body weight explained ~30% of the variability in the final ascorbate concentration. Overall, our analysis revealed that supplementation with 50 mg/day vitamin C, which resulted in a total dietary vitamin C intake of 75 mg/day, was insufficient to achieve adequate plasma ascorbate concentrations in individuals with hypovitaminosis C. Furthermore, increased body weight had a negative impact on ascorbate status.

Effect of vitamin C supplementation on lipid profile, serum uric acid, and ascorbic acid in children on hemodialysis.

PubMed

El Mashad, Ghada Mohamed; ElSayed, Hanan M; Nosair, Nahla A

2016-01-01

Children with end-stage renal disease (ESRD) suffer from dyslipidemia and hyperuricemia that might play a causal role in the progression of cardiovascular disease (CVD). The aim of the study is to assess the effects of Vitamin C supplementation on uric acid, ascorbic acid, and serum lipid levels among children on hemodialysis (HD). This prospective study was conducted in the pediatric nephrology unit at Menoufia University Hospital. The study included a total of 60 children with ESRD on maintenance HD therapy. They were divided into two groups: Group I (supplemented group, n = 30) received intravenous Vitamin C supplementation and Group II (control, n = 30) received placebo (intravenous saline) for three months. The results are shown as a mean ± standard deviation. Statistical evaluation was performed by SPSS software (version 11.5) using paired t-test. After supplementation with Vitamin C, the serum Vitamin C and high-density lipoprotein levels increased significantly with a significant reduction in the levels of serum uric acid, cholesterol, low-density lipoproteins, and triglyceride at the end of the study period. No significant changes were observed in the control group. Vitamin C can serve as a useful urate lowering medicine in HD patients to avoid complications of hyperuricemia. Furthermore, it had favorable effects on the lipid profile. This improvement can be considered as a preventive strategy in the progression of CVD in HD patients. Vitamin C supplementation improves ascorbic acid deficiency in these patients.

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.

PubMed

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 (<0.01%) or in the 5% to 10% range. Calcium Ascorbate and Magnesium Ascorbate are described as antioxidants and skin conditioning agents--miscellaneous for use in cosmetics, but are not currently used. 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

Kolaviron and L-Ascorbic Acid Attenuate Chlorambucil-Induced Testicular Oxidative Stress in Rats

PubMed Central

2014-01-01

Chlorambucil (4-[4-[bis(2-chloroethyl)amino]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. PMID:25309592

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.

PubMed

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. Copyright © 2015 Elsevier B.V. All rights reserved.

Peroxydisulfate Oxidation of L-Ascorbic Acid for Its Direct Spectrophotometric Determination in Dietary Supplements

NASA Astrophysics Data System (ADS)

Salkić, M.; Selimović, A.; Pašalić, H.; Keran, H.

2014-03-01

A selective and accurate direct spectrophotometric method was developed for the determination of L-as cor bic acid in dietary supplements. Background correction was based on the oxidation of L-ascorbic acid by potassi um peroxydisulfate in an acidic medium. The molar absorptivity of the proposed method was 1.41 · 104 l/(mol · cm) at 265 nm. The method response was linear up to an L-ascorbic acid concentration of 12.00 μg/ml. The detection limit was 0.11 μg/ml, and the relative standard deviation was 0.9 % (n = 7) for 8.00 μg/ml L-ascorbic acid. Other compounds commonly found in the dietary supplements did not interfere with the detection of L-ascorbic acid. The proposed procedure was successfully applied to the determination of L-ascorbic acid in these supplements, and the results obtained agreed with those obtained by iodine titration.

The role of topically applied L-ascorbic acid in ex-vivo examination of burn-injured human skin

NASA Astrophysics Data System (ADS)

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.

Hydrolytic and oxidate stability of L-(+) -ascorbic acid supported in pectin films: Influence of the macromolecular structure and calcium presence

USDA-ARS?s Scientific Manuscript database

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...

Dietary vitamin A, ascorbic acid and α-tocopherol affect the gonad development and reproductive performance of starry flounder Platichthys stellatus broodstock

NASA Astrophysics Data System (ADS)

Wang, Jiying; Li, Baoshan; Liu, Xudong; Ma, Jingjing; Wang, Shixin; Zhang, Limin

2014-03-01

The present trial was conducted with starry flounder Platichthys stellatus broodstock to evaluate the effects of dietary vitamin A, ascorbic acid, and α-tocopherol on the gonadal development and reproductive performance. 8 000 IU/kg diet vitamin A (VA group), 500 mg/kg diet ascorbic acid (Vcpp group), or 250 mg/kg diet α-tocopherol (α-TA group) was added into basal diet to create 3 vitamin experimental diets, respectively. Each diet was fed to 450 starry flounder broodstock for 104 days. Samples were collected weekly. The gonadosomatic index (GSI) of 3 vitamin experimental groups first decreased and then increased. Maximum GSI of Vcpp group was higher than that of α-TA group but lower than that of VA group. The spawning periods of 3 vitamin experimental groups lasted 49, 56, and 45 days, respectively. No mature eggs were observed in the control group during the trial. The absolute fecundity (AF) and relative fecundity (RF) of α-TA group was higher than that of Vcpp group but lower than that of VA group. The results suggest that different vitamins play different roles in the fish reproductive process. Vitamin A stimulated the maturation of the ovary, ascorbic acid prolonged the spawning period, and α-tocopherol affected the development of the eggs.

The preparation and the sustained release of titanium dioxide hollow particles encapsulating L-ascorbic acid

NASA Astrophysics Data System (ADS)

Tominaga, Yoko; Kadota, Kazunori; Shimosaka, Atsuko; Yoshida, Mikio; Oshima, Kotaro; Shirakawa, Yoshiyuki

2018-05-01

The preparation of the titanium dioxide hollow particles encapsulating L-ascorbic acid via sol-gel process using inkjet nozzle has been performed, and the sustained release and the effect protecting against degradation of L-ascorbic acid in the particles were investigated. The morphology of titanium dioxide particles was evaluated by scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS). The sustained release and the effect protecting against degradation of L-ascorbic acid were estimated by dialysis bag method in phosphate buffer saline (PBS) (pH = 7.4) as release media. The prepared titanium dioxide particles exhibited spherical porous structures. The particle size distribution of the titanium dioxide particles was uniform. The hollow titanium dioxide particles encapsulating L-ascorbic acid showed the sustained release. It was also found that the degradation of L-ascorbic acid could be inhibited by encapsulating L-ascorbic acid in the titanium dioxide hollow particles.

Variation in the SLC23A1 gene does not influence cardiometabolic outcomes to the extent expected given its association with L-ascorbic acid.

PubMed

Wade, Kaitlin H; Forouhi, Nita G; Cook, Derek G; Johnson, Paul; McConnachie, Alex; Morris, Richard W; Rodriguez, Santiago; Ye, Zheng; Ebrahim, Shah; Padmanabhan, Sandosh; Watt, Graham; Bruckdorfer, K Richard; Wareham, Nick J; Whincup, Peter H; Chanock, Stephen; Sattar, Naveed; Lawlor, Debbie A; Davey Smith, George; Timpson, Nicholas J

2015-01-01

Observational studies showed that circulating L-ascorbic acid (vitamin C) is inversely associated with cardiometabolic traits. However, these studies were susceptible to confounding and reverse causation. We assessed the relation between L-ascorbic acid and 10 cardiometabolic traits by using a single nucleotide polymorphism in the solute carrier family 23 member 1 (SLC23A1) gene (rs33972313) associated with circulating L-ascorbic acid concentrations. The observed association between rs33972313 and cardiometabolic outcomes was compared with that expected given the rs33972313-L-ascorbic acid and L-ascorbic acid-outcome associations. A meta-analysis was performed in the following 5 independent studies: the British Women's Heart and Health Study (n = 1833), the MIDSPAN study (n = 1138), the Ten Towns study (n = 1324), the British Regional Heart Study (n = 2521), and the European Prospective Investigation into Cancer (n = 3737). With the use of a meta-analysis of observational estimates, inverse associations were shown between L-ascorbic acid and systolic blood pressure, triglycerides, and the waist-hip ratio [the strongest of which was the waist-hip ratio (-0.13-SD change; 95% CI: -0.20-, -0.07-SD change; P = 0.0001) per SD increase in L-ascorbic acid], and a positive association was shown with high-density lipoprotein (HDL) cholesterol. The variation at rs33972313 was associated with a 0.18-SD (95% CI: 0.10-, 0.25-SD; P = 3.34 × 10⁻⁶) increase in L-ascorbic acid per effect allele. There was no evidence of a relation between the variation at rs33972313 and any cardiometabolic outcome. Although observed estimates were not statistically different from expected associations between rs33972313 and cardiometabolic outcomes, estimates for low-density lipoprotein cholesterol, HDL cholesterol, triglycerides, glucose, and body mass index were in the opposite direction to those expected. The nature of the genetic association exploited in this study led to limited

Synthesis of L-ascorbic acid in the phloem

PubMed Central

Hancock, Robert D; McRae, Diane; Haupt, Sophie; Viola, Roberto

2003-01-01

Background Although plants are the main source of vitamin C in the human diet, we still have a limited understanding of how plants synthesise L-ascorbic acid (AsA) and what regulates its concentration in different plant tissues. In particular, the enormous variability in the vitamin C content of storage organs from different plants remains unexplained. Possible sources of AsA in plant storage organs include in situ synthesis and long-distance transport of AsA synthesised in other tissues via the phloem. In this paper we examine a third possibility, that of synthesis within the phloem. Results We provide evidence for the presence of AsA in the phloem sap of a wide range of crop species using aphid stylectomy and histochemical approaches. The activity of almost all the enzymes of the primary AsA biosynthetic pathway were detected in phloem-rich vascular exudates from Cucurbita pepo fruits and AsA biosynthesis was demonstrated in isolated phloem strands from Apium graveolens petioles incubated with a range of precursors (D-glucose, D-mannose, L-galactose and L-galactono-1,4-lactone). Phloem uptake of D-[U-14C]mannose and L-[1-14C]galactose (intermediates of the AsA biosynthetic pathway) as well as L-[1-14C]AsA and L-[1-14C]DHA, was observed in Nicotiana benthamiana leaf discs. Conclusions We present the novel finding that active AsA biosynthesis occurs in the phloem. This process must now be considered in the context of mechanisms implicated in whole plant AsA distribution. This work should provoke studies aimed at elucidation of the in vivo substrates for phloem AsA biosynthesis and its contribution to AsA accumulation in plant storage organs. PMID:14633288

Effects of L-ascorbic acid on physicochemical characteristics of wheat starch.

PubMed

Majzoobi, Mahsa; Radi, Mohsen; Farahnaky, Asgar; Tongdang, Tawee

2012-03-01

The main objective of this study was to determine the effects of l-ascorbic acid, as a permitted additive in bakery products, on characteristics of wheat starch. Suspensions of wheat starch (30%, w/w) in water containing 140 mg/kg ascorbic acid before and after gelatinization were prepared and studied using different techniques. The results of scanning electron microscopy showed that some spots appeared on the surface of the starch granules as a result of the addition of ascorbic acid. However, no changes in the starch crystalline pattern and its degree of crystallinity were observed by X-ray diffraction technique. For ungelatinized samples, no difference in the pasting properties of the samples was determined by the rapid visco analyzer, whereas for the gelatinized samples, peak and final viscosities decreased for the samples contained ascorbic acid. Determination of the intrinsic viscosities of the samples showed that addition of ascorbic acid to the gelatinized samples reduced the intrinsic viscosity. In general, it was found that ascorbic acid had some degradation effects on wheat starch molecules particularly after gelatinization. © 2012 Institute of Food Technologists®

Comparing the moisturizing effects of ascorbic acid and calcium ascorbate against that of tocopherol in emulsions.

PubMed

Gönüllü, U; Sensoy, D; Uner, M; Yener, G; Altinkurt, T

2006-01-01

Calcium ascorbate (CAAS), which is a hydrophilic and stable derivative of ascorbic acid (vitamin C) (AA), is commonly used in foods as an antioxidative agent. There are very limited reports on its dermatological use in the literature. In this paper, it is reported that CAAS could be used in place of ascorbic acid, which has chemical stability problems in topicals due to degradation by oxidation. The aim of this study was to investigate the skin-hydrating effect of CAAS compared to those of ascorbic acid and tocopherol (vitamin E) (T), which is a potential skin moisturizer and commonly used in dermocosmetics. Vitamins are incorporated into two kinds of base creams (o/w and w/o emulsion creams), alone and in combinations. Formulations were applied to the inner forearms of volunteers, and skin conductance was measured by using a corneometer. Data obtained were statistically evaluated. It was found that the skin-hydrating effect of CAAS was higher than that of AA and lower than that of T. However, its effect was very close to that of T.

Expression of Ascorbic Acid Oxidase in Zucchini Squash (Cucurbita pepo L.).

PubMed

Lin, L S; Varner, J E

1991-05-01

The expression of ascorbic acid oxidase was studied in zucchini squash (Cucurbita pepo L.), one of the most abundant natural sources of the enzyme. In the developing fruit, specific activity of ascorbic acid oxidase was highest between 4 and 6 days after anthesis. Protein and mRNA levels followed the same trend as enzyme activity. Highest growth rate of the fruit occurred before 6 days after anthesis. Within a given fruit, ascorbic acid oxidase activity and mRNA level were highest in the epidermis, and lowest in the central placental region. In leaf tissue, ascorbic acid oxidase activity was higher in young leaves, and very low in old leaves. Within a given leaf, enzyme activity was highest in the fast-growing region (approximately the lower third of the blade), and lowest in the slow-growing region (near leaf apex). High expression of ascorbic acid oxidase at a stage when rapid growth is occurring (in both fruits and leaves), and localization of the enzyme in the fruit epidermis, where cells are under greatest tension during rapid growth in girth, suggest that ascorbic acid oxidase might be involved in reorganization of the cell wall to allow for expansion. Based on the known chemistry of dehydroascorbic acid, the end product of the ascorbic acid oxidase-catalyzed reaction, we have proposed several hypotheses to explain how dehydroascorbic acid might cause cell wall "loosening."

Supplementation of Ascorbic Acid in Weanling Horses Following Prolonged Transportation

PubMed Central

Ralston, Sarah; Stives, Michelle

2012-01-01

Simple Summary Horses normally synthesize adequate amounts of ascorbic acid (vitamin C) in their liver to meet their needs for the vitamin. However, prolonged stress results in low plasma concentrations and reduced immune function. Weanling horses were supplemented with ascorbic acid for 5 or 10 days or no ascorbic acid (4 per group) following 50+ hours of transportation. Supplementation caused increases in plasma concentrations but both supplemented groups had decreased plasma ascorbic acid for 1 to 3 weeks following cessation of supplementation, possibly due to suppressed synthesis. Supplementation of ascorbic acid following prolonged stress will increase plasma concentrations, but prolonged supplementation should be avoided. Abstract 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. PMID:26486916

Coordination chemistry of vitamin C. Part I. Interaction of L-ascorbic acid with alkaline earth metal ions in the crystalline solid and aqueous solution.

PubMed

Tajmir-Riahi, H A

1990-10-01

The interaction of L-ascorbic acid with alkaline earth metal ions has been investigated in aqueous solution at pH 6-7. The solid salts of the type Mg(L-ascorbate)2.4H2O, Ca(L-ascorbate)2.2H2O, Sr(L-ascorbate)2.2H2O and Ba(L-ascorbate)2.2H2O were isolated and characterized by means of 13C NMR and FT-IR spectroscopy. Spectroscopic and other evidence suggested that in aqueous solution, the binding of the alkaline earth metal ions is through the O-3 atom of the ascorbate anion, while in the solid state the binding of the Mg(II) is different from those of the other alkaline earth metal ion salts. The Mg(II) ion binds to the O-3, O-1 atom of the two ascorbate anions and to two H2O molecules, while the eight-coordination around the Ca(II), Sr(II), and Ba(II) ions would be completed by the coordination of three acid anions, through O-5, O-6 of the first, O-3, O-5, O-6 of the second and O-1 of the third anion as well as to two H2O molecules. The structural properties of the alkaline earth metal-ascorbate salts are different in the solid and aqueous solution.

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

PubMed

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. Copyright © 2014 Elsevier B.V. All rights reserved.

Ascorbate as a Biosynthetic Precursor in Plants

PubMed Central

Debolt, Seth; Melino, Vanessa; Ford, Christopher M.

2007-01-01

Background and Aims l-Ascorbate (vitamin C) has well-documented roles in many aspects of redox control and anti-oxidant activity in plant cells. This Botanical Briefing highlights recent developments in another aspect of l-ascorbate metabolism: its function as a precursor for specific processes in the biosynthesis of organic acids. Scope The Briefing provides a summary of recent advances in our understanding of l-ascorbate metabolism, covering biosynthesis, translocation and functional aspects. The role of l-ascorbate as a biosynthetic precursor in the formation of oxalic acid, l-threonic acid and l-tartaric acid is described, and progress in elaborating the mechanisms of the formation of these acids is reviewed. The potential conflict between the two roles of l-ascorbate in plant cells, functional and biosynthetic, is highlighted. Conclusions Recent advances in the understanding of l-ascorbate catabolism and the formation of oxalic and l-tartaric acids provide compelling evidence for a major role of l-ascorbate in plant metabolism. Combined experimental approaches, using classic biochemical and emerging ‘omics’ technologies, have provided recent insight to previously under-investigated areas. PMID:17098753

An acute study on the relative gastro-intestinal absorption of a novel form of calcium ascorbate.

PubMed

Bush, M J; Verlangieri, A J

1987-07-01

Several functions of L-ascorbic acid (vitamin C) have been suggested in addition to its role in the prevention of scurvy. Consequently, a controversy has arisen over the daily intake of the vitamin which will afford maximum benefits. Rapid cellular uptake and delayed renal excretion of ascorbic acid would be conducive to providing optimum cellular concentration for biochemical activity. ESTER-C (patent pending), a complex consisting of L-ascorbic acid and Ca++, has been recently developed by Inter-Cal Corporation (421 Miller Road, Prescott, AZ 86301). It has been proposed that the structure of ESTER-C may render it more readily absorbed and less rapidly excreted than the acid or salt form of the vitamin. To test this hypothesis, ESTER-C and L-ascorbic acid were administered to two groups of rats. Blood was sampled at 20, 40, 80, 160 and 240 minutes and plasma analyzed for ascorbic acid. As urine appeared in collection cups, it was tested qualitatively for the presence of ascorbic acid. The plasma concentration of ascorbic acid was higher in ESTER-C treated rats at 20, 40 and 80 minutes than in rats given L-ascorbic acid. Ascorbic acid was detected in the urine of animals administered ESTER-C later than in those treated with L-ascorbic acid. These results support the hypothesis that ESTER-C is absorbed more readily and excreted less rapidly than L-ascorbic acid.

The amphiphilic alkyl ester derivatives of l-ascorbic acid induce reorganization of phospholipid vesicles.

PubMed

Giudice, Francesca; Ambroggio, Ernesto E; Mottola, Milagro; Fanani, Maria Laura

2016-09-01

l-ascorbic acid alkyl esters (ASCn) are lipophilic forms of vitamin C, which maintain some of its antioxidant power. Those properties make this drug family attractive to be used in pharmacological preparations protecting other redox-sensible drugs or designed to reduce possible toxic oxidative processes. In this work, we tested the ability of l-ascorbic acid alkyl esters (ASCn) to modulate the structure, permeability, and rheological properties of phospholipid bilayers. The ASCn studied here (ASC16, ASC14, and ASC12) alter the structural integrity as well as the rheological properties of phospholipid membranes without showing any evident detergent activity. ASC14 appeared as the most efficient drug in destabilize the membrane structure of nano- and micro-size phospholipid liposomes inducing vesicle content leakage and shape elongation on giant unilamellar vesicles. It also was the most potent enhancer of membrane microviscosity and surface water structuring. Only ASC16 induced the formation of drug-enriched condensed domains after its incorporation into the lipid bilayer, while ASC12 appeared as the less membrane-disturbing compound, likely because of its poor, and more superficial, partition into the membrane. We also found that incorporation of ASCn into the lipid bilayers enhanced the reduction of membrane components, compared with soluble vitamin C. Our study shows that ASCn compounds, which vary in the length of the acyl chain, show different effects on phospholipid vesicles used as biomembrane models. Those variances may account for subtly differences in the effectiveness on their pharmacological applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Variation in the SLC23A1 gene does not influence cardiometabolic outcomes to the extent expected given its association with l-ascorbic acid1234

PubMed Central

Wade, Kaitlin H; Forouhi, Nita G; Cook, Derek G; Johnson, Paul; McConnachie, Alex; Morris, Richard W; Rodriguez, Santiago; Ye, Zheng; Ebrahim, Shah; Padmanabhan, Sandosh; Watt, Graham; Bruckdorfer, K Richard; Wareham, Nick J; Whincup, Peter H; Chanock, Stephen; Sattar, Naveed; Lawlor, Debbie A; Davey Smith, George; Timpson, Nicholas J

2015-01-01

Background: Observational studies showed that circulating l-ascorbic acid (vitamin C) is inversely associated with cardiometabolic traits. However, these studies were susceptible to confounding and reverse causation. Objectives: We assessed the relation between l-ascorbic acid and 10 cardiometabolic traits by using a single nucleotide polymorphism in the solute carrier family 23 member 1 (SLC23A1) gene (rs33972313) associated with circulating l-ascorbic acid concentrations. The observed association between rs33972313 and cardiometabolic outcomes was compared with that expected given the rs33972313-l-ascorbic acid and l-ascorbic acid–outcome associations. Design: A meta-analysis was performed in the following 5 independent studies: the British Women's Heart and Health Study (n = 1833), the MIDSPAN study (n = 1138), the Ten Towns study (n = 1324), the British Regional Heart Study (n = 2521), and the European Prospective Investigation into Cancer (n = 3737). Results: With the use of a meta-analysis of observational estimates, inverse associations were shown between l-ascorbic acid and systolic blood pressure, triglycerides, and the waist-hip ratio [the strongest of which was the waist-hip ratio (−0.13-SD change; 95% CI: −0.20-, −0.07-SD change; P = 0.0001) per SD increase in l-ascorbic acid], and a positive association was shown with high-density lipoprotein (HDL) cholesterol. The variation at rs33972313 was associated with a 0.18-SD (95% CI: 0.10-, 0.25-SD; P = 3.34 × 10−6) increase in l-ascorbic acid per effect allele. There was no evidence of a relation between the variation at rs33972313 and any cardiometabolic outcome. Although observed estimates were not statistically different from expected associations between rs33972313 and cardiometabolic outcomes, estimates for low-density lipoprotein cholesterol, HDL cholesterol, triglycerides, glucose, and body mass index were in the opposite direction to those expected. Conclusions: The nature of the genetic

Nutritional aspects of ascorbic acid: uses and abuses.

PubMed

Vilter, R W

1980-12-01

Ascorbic acid in physiological doses is essential for the normal functioning of the human body. Larger doses are required to treat a severe deficiency of vitamin C intake, as in the case of scurvy. Occasionally, massive doses may be required to treat a metabolic defect involving ascorbic acid. There has been some mention of megadose therapy with ascorbic acid for the prevention of colds, the improved healing of wounds and even the treatment of cancer, but no acceptable scientific data have been presented. In fact, in a few instances, such therapy has proved injurious.

Biosynthesis of l-Ascorbic Acid and Conversion of Carbons 1 and 2 of l-Ascorbic Acid to Oxalic Acid Occurs within Individual Calcium Oxalate Crystal Idioblasts1

PubMed Central

Kostman, Todd A.; Tarlyn, Nathan M.; Loewus, Frank A.; Franceschi, Vincent R.

2001-01-01

l-Ascorbic acid (AsA) and its metabolic precursors give rise to oxalic acid (OxA) found in calcium oxalate crystals in specialized crystal idioblast cells in plants; however, it is not known if AsA and OxA are synthesized within the crystal idioblast cell or transported in from surrounding mesophyll cells. Isolated developing crystal idioblasts from Pistia stratiotes were used to study the pathway of OxA biosynthesis and to determine if idioblasts contain the entire path and are essentially independent in OxA synthesis. Idioblasts were supplied with various 14C-labeled compounds and examined by micro-autoradiography for incorporation of 14C into calcium oxalate crystals. [14C]OxA gave heavy labeling of crystals, indicating the isolated idioblasts are functional in crystal formation. Incubation with [1-14C]AsA also gave heavy labeling of crystals, whereas [6-14C]AsA gave no labeling. Labeled precursors of AsA (l-[1-14C]galactose; d-[1-14C]mannose) also resulted in crystal labeling, as did the ascorbic acid analog, d-[1-14C]erythorbic acid. Intensity of labeling of isolated idioblasts followed the pattern OxA > AsA (erythorbic acid) > l-galactose > d-mannose. Our results demonstrate that P. stratiotes crystal idioblasts synthesize the OxA used for crystal formation, the OxA is derived from the number 1 and 2 carbons of AsA, and the proposed pathway of ascorbic acid synthesis via d-mannose and l-galactose is operational in individual P. stratiotes crystal idioblasts. These results are discussed with respect to fine control of calcium oxalate precipitation and the concept of crystal idioblasts as independent physiological compartments. PMID:11161021

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

PubMed

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.

Influence of trace elements on stabilization of aqueous solutions of ascorbic acid.

PubMed

Dolińska, Barbara; Ostróżka-Cieślik, Aneta; Caban, Artur; Rimantas, Klimas; Leszczyńska, Lucyna; Ryszka, Florian

2012-12-01

Together with vitamin C, zinc, selenium, manganese, and magnesium play a vital role in the preservation of organs scheduled for transplantation. In the present study, it is shown that addition of 1 mg/l of these elements influences the stability of 0.3 mM ascorbic acid solutions. The solution's stability was estimated using an accelerated stability test. The concentration of vitamin C was measured using a validated spectrophotometric method, which uses the reduction of 2,6-dichlorophenoloindophenol by ascorbic acid. Elevated temperatures, the factor accelerating substances' decomposition reaction rate, were used in the tests. The research was conducted at two temperatures at intervals of 10 °C: 80 ± 0.1 and 90 ± 0.1 °C. It was stated that the studied substances' decomposition occurred in accordance with the equation for first-order reactions. The function of the logarithmic concentration (log%C) over time was revealed to be rectilinear. This dependence was used to determine the kinetics of decomposition reaction rate parameters. The stabilization of vitamin C solutions was measured as the time in which 10 % of the substance decomposed at 20 and 0 °C. Addition of Se(IV) or Mg(II) ions significantly increase the stability of ascorbic acid solution (∼34 and ∼16 %, respectively), but Zn(II) causes a significant decrease in stability by ∼23 %. Addition of Mn(II) has no significant influence on vitamin C stability.

Impact of Oxidative Stress on Ascorbate Biosynthesis in Chlamydomonas via Regulation of the VTC2 Gene Encoding a GDP-l-galactose Phosphorylase*

PubMed Central

Urzica, Eugen I.; Adler, Lital N.; Page, M. Dudley; Linster, Carole L.; Arbing, Mark A.; Casero, David; Pellegrini, Matteo; Merchant, Sabeeha S.; Clarke, Steven G.

2012-01-01

The l-galactose (Smirnoff-Wheeler) pathway represents the major route to l-ascorbic acid (vitamin C) biosynthesis in higher plants. Arabidopsis thaliana VTC2 and its paralogue VTC5 function as GDP-l-galactose phosphorylases converting GDP-l-galactose to l-galactose-1-P, thus catalyzing the first committed step in the biosynthesis of l-ascorbate. Here we report that the l-galactose pathway of ascorbate biosynthesis described in higher plants is conserved in green algae. The Chlamydomonas reinhardtii genome encodes all the enzymes required for vitamin C biosynthesis via the l-galactose pathway. We have characterized recombinant C. reinhardtii VTC2 as an active GDP-l-galactose phosphorylase. C. reinhardtii cells exposed to oxidative stress show increased VTC2 mRNA and l-ascorbate levels. Genes encoding enzymatic components of the ascorbate-glutathione system (e.g. ascorbate peroxidase, manganese superoxide dismutase, and dehydroascorbate reductase) are also up-regulated in response to increased oxidative stress. These results indicate that C. reinhardtii VTC2, like its plant homologs, is a highly regulated enzyme in ascorbate biosynthesis in green algae and that, together with the ascorbate recycling system, the l-galactose pathway represents the major route for providing protective levels of ascorbate in oxidatively stressed algal cells. PMID:22393048

Diffusive properties of Vitamin C aqueous solutions by quasielastic neutron scattering

NASA Astrophysics Data System (ADS)

Migliardo, F.; Magazù, S.; Migliardo, P.

2001-07-01

Quasi elastic neutron scattering (QENS) results on aqueous solutions of L-ascorbic acid (Vitamin C) are reported. Data, collected by the IRIS spectrometer at the ISIS facility on partially deuterated L-ascorbic acid in D 2O and on hydrogenated L-ascorbic acid in H 2O, allow to characterize the diffusive dynamics of both hydrated Vitamin C and water, revealing that this latter is strongly affected by the presence of L-ascorbic acid and furnishing a hydration number value of ∼5 at T=33°C.

[Cellular and intracellular transport of vitamin C. The physiologic aspects].

PubMed

Szarka, András; Lőrincz, Tamás

2013-10-20

Vitamin C requirement is satisfied by natural sources and vitamin C supplements in the ordinary human diet. The two major forms of vitamin C in the diet are L-ascorbic acid and L-dehydroascorbic acid. Both ascorbate and dehydroascorbate are absorbed along the entire length of the human intestine. The reduced form, L-ascorbic acid is imported by an active mechanism, requiring two sodium-dependent vitamin C transporters (SVCT1 and SVCT2). The transport of the oxidized form, dehydroascorbate is mediated by glucose transporters GLUT1, GLUT3 and possibly GLUT4. Initial rate of uptake of both ascorbate and dehydroascorbate is saturable with increasing external substrate concentration. Vitamin C plasma concentrations are tightly controlled when the vitamin is taken orally. It has two simple reasons, on the one hand, the capacity of the transporters is limited, on the other hand the two Na+-dependent transporters can be down-regulated by an elevated level of ascorbate.

Chemical Transport Knockout for Oxidized Vitamin C, Dehydroascorbic Acid, Reveals Its Functions in vivo.

PubMed

Tu, Hongbin; Wang, Yu; Li, Hongyan; Brinster, Lauren R; Levine, Mark

2017-09-01

Despite its transport by glucose transporters (GLUTs) in vitro, it is unknown whether dehydroascorbic acid (oxidized vitamin C, DHA) has any in vivo function. To investigate, we created a chemical transport knockout model using the vitamin C analog 6-bromo-ascorbate. This analog is transported on sodium-dependent vitamin C transporters but its oxidized form, 6-bromo-dehydroascorbic acid, is not transported by GLUTs. Mice (gulo -/- ) unable to synthesize ascorbate (vitamin C) were raised on 6-bromo-ascorbate. Despite normal survival, centrifugation of blood produced hemolysis secondary to near absence of red blood cell (RBC) ascorbate/6-bromo-ascorbate. Key findings with clinical implications were that RBCs in vitro transported dehydroascorbic acid but not bromo-dehydroascorbic acid; RBC ascorbate in vivo was obtained only via DHA transport; ascorbate via DHA transport in vivo was necessary for RBC structural integrity; and internal RBC ascorbate was essential to maintain ascorbate plasma concentrations in vitro/in vivo. Published by Elsevier B.V.

Interference of ascorbic acid with chemical analytes.

PubMed

Meng, Qing H; Irwin, William C; Fesser, Jennifer; Massey, K Lorne

2005-11-01

Ascorbic acid can interfere with methodologies involving redox reactions, while comprehensive studies on main chemistry analysers have not been reported. We therefore attempted to determine the interference of ascorbic acid with analytes on the Beckman Synchron LX20. Various concentrations of ascorbic acid were added to serum, and the serum analytes were measured on the LX20. With a serum ascorbic acid concentration of 12.0 mmol/L, the values for sodium, potassium, calcium and creatinine increased by 43%, 58%, 103% and 26%, respectively (P<0.01). With a serum ascorbic acid concentration of 12.0 mmol/L, the values for chloride, total bilirubin and uric acid decreased by 33%, 62% and 83%, respectively (P<0.01), and were undetectable for total cholesterol, triglyceride, ammonia and lactate. There was no definite influence of ascorbic acid on analytical values for total CO(2), urea, glucose, phosphate, total protein, albumin, amylase, creatine kinase, creatine kinase-MB, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total iron, unbound iron-binding capacity or magnesium. Ascorbic acid causes a false increase in sodium, potassium, calcium and creatinine results and a false decrease in chloride, total bilirubin, uric acid, total cholesterol, triglyceride, ammonia and lactate results.

Modelling and analysis of a direct ascorbic acid fuel cell

NASA Astrophysics Data System (ADS)

Zeng, Yingzhi; Fujiwara, Naoko; Yamazaki, Shin-ichi; Tanimoto, Kazumi; Wu, Ping

L-Ascorbic acid (AA), also known as vitamin C, is an environmentally-benign and biologically-friendly compound that can be used as an alternative fuel for direct oxidation fuel cells. While direct ascorbic acid fuel cells (DAAFCs) have been studied experimentally, modelling and simulation of these devices have been overlooked. In this work, we develop a mathematical model to describe a DAAFC and validate it with experimental data. The model is formulated by integrating the mass and charge balances, and model parameters are estimated by best-fitting to experimental data of current-voltage curves. By comparing the transient voltage curves predicted by dynamic simulation and experiments, the model is further validated. Various parameters that affect the power generation are studied by simulation. The cathodic reaction is found to be the most significant determinant of power generation, followed by fuel feed concentration and the mass-transfer coefficient of ascorbic acid. These studies also reveal that the power density steadily increases with respect to the fuel feed concentration. The results may guide future development and operation of a more efficient DAAFC.

Electronic structures and spectra of two antioxidants: uric acid and ascorbic acid

NASA Astrophysics Data System (ADS)

Shukla, M. K.; Mishra, P. C.

1996-04-01

Electronic absorption and fluorescence spectra of aqueous solutions of two well known antioxidants, uric acid and ascorbic acid (vitamin C), have been studied at different pH. The observed spectra have been interpreted in terms of neutral and anionic forms of the molecules with the help of molecular orbital calculations. The N 3 site of uric acid has been shown to be the most acidic. Fluorescence of uric acid seems to originate from an anion of the molecule in a wide pH range. Around pH 3, both the neutral and anionic forms of ascorbic acid appear to be present in aqueous solutions. In aqueous media, ascorbic acid appears to get converted easily to its dehydro form and this conversion does not seem to be reversible. An anion of dehydroascorbic acid seems to be formed on heating dehydroascorbic acid in aqueous solutions.

Heavy metals influence on ascorbic acid level

NASA Astrophysics Data System (ADS)

Kamaldinov, E. V.; Patrashkov, S. A.; Batenyeva, E. V.; Korotkevich, O. S.

2003-05-01

It is well known that heavy metals (HM) are extremely dangerous pollutants influencing to metabolism in animals' organisms. The vitamin C is one of the most important metabolites taking part in many biochemical processes. We studied the influence of main essential HM-Zn and Cu as well as the based supertoxical elements - Cd and Pd on ascorbic acid level in serum. The studies were carried out in Tulinskoe farm of Novosibirsk region. The objects of investigations were piglets (2 month after weaning) and 6-month pigs of Early Ripe Meat breed. The levels of HM in bristle were found by stripping voltammetric analysis using the TA-2 analyzer. Vitamin C content was determined by I.P. Kondrakhin (1985) method using 2,2-dipyridyl. The significant negative correlations between Pb, Cd content and vitamin C (-0.46 ± 0.18, -0.47 ± 0.19) in 6-month pigs were determined. The tendencies of negative correlation between all HM levels in hair and ascorbic acid level in plasma of piglets were revealed. Thus, the obtained correlations let us to suppose that all studied HM influence on 1-gulono-gamma-lactone oxidase and other vitamin C metabolism enzymes activity.

[Concentration of glutathione (GSH), ascorbic acid (vitamin C) and substances reacting with thiobarbituric acid (TBA-rs) in single human brain metastases].

PubMed

Dudek, Henryk; Farbiszewski, Ryszard; Rydzewska, Maria; Michno, Tadeusz; Kozłowski, Andrzej

2005-01-01

The aim of the study was to estimate the concentration of glutathione (GSH), ascorbic acid (vitamin C) and thiobarbituric acid (TBA-rs) in single human brain metastases and histologically unchanged nerve tissue. The research was conducted on fragments of neoplasmatic tissue collected from 45 patients undergoing surgery in the Department of Neurosurgery, Medical University of Białystok in years 1996-2002. Concentration of GSH was evaluated using the GSH-400 method, vitamin C using the method of Kyaw and TBA-rs using the method of Salaris and Babs. It has been found that there is a decrease of concentration of GSH and vitamin C and a considerable increase (p < 0.05) of concentration of TBA-rs in investigated single brain human metastasis in correlation to the concentration of the mentioned above substances in unchanged nerve tissue.

Ascorbic acid deficiency in patients with lichen planus.

PubMed

Nicolae, Ilinca; Mitran, Cristina Iulia; Mitran, Madalina Irina; Ene, Corina Daniela; Tampa, Mircea; Georgescu, Simona Roxana

2017-01-01

Recent studies have highlighted the role of oxidative stress in the pathogenesis of lichen planus (LP). In the present study, the interest of the authors is focused on the investigation of ascorbic acid status in patients with LP and identification of parameters that might influence the level of this vitamin. We analyzed the level of urinary ascorbic acid (reflectometric method) in 77 patients with LP (cutaneous LP (CLP)-49 cases; oral LP (OLP)-28 cases) and 50 control subjects. The evaluation of all participants included clinical examination and laboratory and imaging tests. Compared to the control group (19.82 mg/dl) the level of ascorbic acid was significantly lower both in patients with CLP (8.47 mg/dl, p = 0.001) and in those with OLP (8.04 mg/dl, p = 0.001). In patients with LP it was found that the deficiency of ascorbic acid increases with age (r = -0.318, p = 0.032). The urinary concentrations of ascorbic acid were significantly lower in patients with LP associated with infections compared to patients with LP without infections. The urinary ascorbic acid level may be a useful parameter in identifying patients with LP who are at risk of developing viral or bacterial infections.

An efficient synthesis of tetramic acid derivatives with extended conjugation from L-Ascorbic Acid

PubMed Central

Singh, Biswajit K; Bisht, Surendra S; Tripathi, Rama P

2006-01-01

Background Tetramic acids with polyenyl substituents are an important class of compounds in medicinal chemistry. Both solid and solution phase syntheses of such molecules have been reported recently. Thiolactomycin, a clinical candidate for treatment of tuberculosis has led to further explorations in this class. We have recently developed an efficient synthesis of tetramic acids derivatives from L- ascorbic acid. In continuation of this work, we have synthesised dienyl tetramic acid derivatives. Results 5,6-O-Isopropylidene-ascorbic acid on reaction with DBU led to the formation of tetronolactonyl allyl alcohol, which on oxidation with pyridinium chlorochromate gave the respective tetranolactonyl allylic aldehydes. Wittig olefination followed by reaction of the resulting tetranolactonyl dienyl esters with different amines resulted in the respective 5-hydroxy lactams. Subsequent dehydration of the hydroxy lactams with p-toluene sulphonic acid afforded the dienyl tetramic acid derivatives. All reactions were performed at ambient temperature and the yields are good. Conclusion An efficient and practical method for the synthesis of dienyl tetramic acid derivatives from inexpensive and easily accessible ascorbic acid has been developed. The compounds bear structural similarities to the tetramic acid based polyenic antibiotics and thus this method offers a new and short route for the synthesis of tetramic acid derivatives of biological significance. PMID:17147830

An efficient synthesis of tetramic acid derivatives with extended conjugation from L-ascorbic acid.

PubMed

Singh, Biswajit K; Bisht, Surendra S; Tripathi, Rama P

2006-12-06

Tetramic acids with polyenyl substituents are an important class of compounds in medicinal chemistry. Both solid and solution phase syntheses of such molecules have been reported recently. Thiolactomycin, a clinical candidate for treatment of tuberculosis has led to further explorations in this class. We have recently developed an efficient synthesis of tetramic acids derivatives from L-ascorbic acid. In continuation of this work, we have synthesised dienyl tetramic acid derivatives. 5,6-O-isopropylidene-ascorbic acid on reaction with DBU led to the formation of tetronolactonyl allyl alcohol, which on oxidation with pyridinium chlorochromate gave the respective tetranolactonyl allylic aldehydes. Wittig olefination followed by reaction of the resulting tetranolactonyl dienyl esters with different amines resulted in the respective 5-hydroxy lactams. Subsequent dehydration of the hydroxy lactams with p-toluene sulphonic acid afforded the dienyl tetramic acid derivatives. All reactions were performed at ambient temperature and the yields are good. An efficient and practical method for the synthesis of dienyl tetramic acid derivatives from inexpensive and easily accessible ascorbic acid has been developed. The compounds bear structural similarities to the tetramic acid based polyenic antibiotics and thus this method offers a new and short route for the synthesis of tetramic acid derivatives of biological significance.

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

PubMed

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.

Plasma Levels of Folates, Riboflavin, Vitamin B6, and Ascorbate in Severely Disturbed Children.

ERIC Educational Resources Information Center

Sankar, D. V. Siva

1979-01-01

The plasma levels of folic acid, ascorbic acid, pyridoxine, and riboflavin were studied in 125 severely emotionally disturbed children (ages 5-16 years) to determine whether they had overt vitamin deficiencies. (Author/DLS)

Vitamin C Function in the Brain: Vital Role of the Ascorbate Transporter (SVCT2)

PubMed Central

Harrison, Fiona E.; May, James M.

2009-01-01

Ascorbate (vitamin C) is a vital antioxidant molecule in the brain. However, it also has a number of other important functions, participating as a co-factor in several enzyme reactions including catecholamine synthesis, collagen production and regulation of HIF-1α. Ascorbate is transported into the brain and neurons via the Sodium-dependent Vitamin C Transporter-2 (SVCT2), which causes accumulation of ascorbate within cells against a concentration gradient. Dehydroascorbic acid, the oxidized form of ascorbate, is transported via glucose transporters of the GLUT family. Once in cells, it is rapidly reduced to ascorbate. The highest concentrations of ascorbate in the body are found in the brain and neuroendocrine tissues such as adrenal, although the brain is the most difficult organ to deplete of ascorbate. Combined with regional asymmetry in ascorbate distribution within different brain areas, these facts suggest an important role for ascorbate in the brain. Ascorbate is proposed as a neuromodulator of glutamatergic, dopaminergic, cholinergic and GABAergic transmission and related behaviors. Neurodegenerative diseases typically involve high levels of oxidative stress and thus ascorbate has been posited to have potential therapeutic roles against ischemic stroke, Alzheimer's disease, Parkinson's disease and Huntingdon's disease. PMID:19162177

Featured Molecules: Ascorbic Acid and Methylene Blue

NASA Astrophysics Data System (ADS)

Coleman, William F.; Wildman, Randall J.

2003-05-01

The WebWare molecules of the month for May are featured in several articles in this issue. "Arsenic: Not So Evil After All?" discusses the pharmaceutical uses of methylene blue and its development as the first synthetic drug used against a specific disease. The JCE Classroom Activity "Out of the Blue" and the article "Greening the Blue Bottle" feature methylene blue and ascorbic acid as two key ingredients in the formulation of the blue bottle. You can also see a colorful example of these two molecules in action on the cover. "Sailing on the 'C': A Vitamin Titration with a Twist" describes an experiment to determine the vitamin C (ascorbic acid) content of citrus fruits and challenges students, as eighteenth-century sea captains, to decide the best fruit to take on a long voyage. Fully manipulable (Chime) versions of these and other molecules are available at Only@JCE Online.

l-Tartaric acid synthesis from vitamin C in higher plants

PubMed Central

DeBolt, Seth; Cook, Douglas R.; Ford, Christopher M.

2006-01-01

The biosynthetic pathway of l-tartaric acid, the form most commonly encountered in nature, and its catabolic ties to vitamin C, remain a challenge to plant scientists. Vitamin C and l-tartaric acid are plant-derived metabolites with intrinsic human value. In contrast to most fruits during development, grapes accumulate l-tartaric acid, which remains within the berry throughout ripening. Berry taste and the organoleptic properties and aging potential of wines are intimately linked to levels of l-tartaric acid present in the fruit, and those added during vinification. Elucidation of the reactions relating l-tartaric acid to vitamin C catabolism in the Vitaceae showed that they proceed via the oxidation of l-idonic acid, the proposed rate-limiting step in the pathway. Here we report the use of transcript and metabolite profiling to identify candidate cDNAs from genes expressed at developmental times and in tissues appropriate for l-tartaric acid biosynthesis in grape berries. Enzymological analyses of one candidate confirmed its activity in the proposed rate-limiting step of the direct pathway from vitamin C to tartaric acid in higher plants. Surveying organic acid content in Vitis and related genera, we have identified a non-tartrate-forming species in which this gene is deleted. This species accumulates in excess of three times the levels of vitamin C than comparably ripe berries of tartrate-accumulating species, suggesting that modulation of tartaric acid biosynthesis may provide a rational basis for the production of grapes rich in vitamin C. PMID:16567629

Prospective role of ascorbic acid (vitamin C) in attenuating hexavalent chromium-induced functional and cellular damage in rat thyroid.

PubMed

Qureshi, Irfan Zia; Mahmood, Tariq

2010-07-01

Occupational exposure to toxic heavy metals may render industrial workers with thyroid-related problems. Here, we examined the role of ascorbic acid (vitamin C) against hexavalent chromium Cr (VI)-induced damage in rat thyroid gland. Potassium dichromate (K2Cr2O7) and ascorbic acid doses were 60 microg and 120 mg kg(-1) body wt (intraperitoneally [i.p.]) respectively. Treatment regimens were group I rats, saline treated control; group II, only K2Cr2O7; group III, ascorbic acid 1 hour prior K2Cr2O7; group IV, simultaneous doses of ascorbic acid and K2Cr2O7, and group V, a combined premix dose of ascorbic acid and K2 Cr2O7 (2:1 ratio). Blood samples were taken before dosing the animals and 48 hours post exposure to determine the serum thyroid-stimulating hormone (TSH), free triiodothyronine (FT3) and free thyroxine (FT4) concentrations. Toward end of experiment, rats were sacrificed and thyroid glands were processed to evaluate the extent of cellular insult. Results showed significantly increased TSH and decreased FT3 and FT4 concentrations in groups II, III and IV rats as compared to control levels (p < 0.05). In contrast, in group V rats, serum TSH, FT3 and FT4 concentrations neared control concentrations. Histopathologically, protective effect of ascorbic acid was found in group V rats only, where thyroid gland structure neared control thyroid except the follicular size that was decreased (p < 0.05). Follicular density was no different from control. Basal laminae were intact, interfollicular spaces were normal. Colloid retraction and/or reabsorption were reduced maximally. Epithelial cell height was no different from control; epithelial follicular index increased only 1.3 fold, whereas nuclear-cytoplasmic (N/C) ratio was decreased by 14% only. The study indicates that the ascorbic acid may have the potential to protect thyroid gland from chromium toxicity; however, the study warrants further in-depth experimentation to precisely elucidate this role.

A simple 2D composite image analysis technique for the crystal growth study of L-ascorbic acid.

PubMed

Kumar, Krishan; Kumar, Virender; Lal, Jatin; Kaur, Harmeet; Singh, Jasbir

2017-06-01

This work was destined for 2D crystal growth studies of L-ascorbic acid using the composite image analysis technique. Growth experiments on the L-ascorbic acid crystals were carried out by standard (optical) microscopy, laser diffraction analysis, and composite image analysis. For image analysis, the growth of L-ascorbic acid crystals was captured as digital 2D RGB images, which were then processed to composite images. After processing, the crystal boundaries emerged as white lines against the black (cancelled) background. The crystal boundaries were well differentiated by peaks in the intensity graphs generated for the composite images. The lengths of crystal boundaries measured from the intensity graphs of composite images were in good agreement (correlation coefficient "r" = 0.99) with the lengths measured by standard microscopy. On the contrary, the lengths measured by laser diffraction were poorly correlated with both techniques. Therefore, the composite image analysis can replace the standard microscopy technique for the crystal growth studies of L-ascorbic acid. © 2017 Wiley Periodicals, Inc.

Effect of L-ascorbic acid on nickel-induced alterations in serum lipid profiles and liver histopathology in rats.

PubMed

Das, Kusal K; Gupta, Amrita Das; Dhundasi, Salim A; Patil, Ashok M; Das, Swastika N; Ambekar, Jeevan G

2006-01-01

Nickel exposure greatly depletes intracellular ascorbate and alters ascorbate-cholesterol metabolism. We studied the effect of the simultaneous oral treatment with L-ascorbic acid (50 mg/100 g body weight (BW) and nickel sulfate (2.0 mg/100 g BW, i.p) on nickelinduced changes in serum lipid profiles and liver histopathology. Nickel-treated rats showed a significant increase in serum low-density lipoprotein-cholesterol, total cholesterol, triglycerides, and a significant decrease in serum high-density lipoprotein-cholesterol. In the liver, nickel sulfate caused a loss of normal architecture, fatty changes, extensive vacuolization in hepatocytes, eccentric nuclei, and Kupffer cell hypertrophy. Simultaneous administration of L-ascorbic acid with nickel sulfate improved both the lipid profile and liver impairments when compared with rats receiving nickel sulfate only. The results indicate that L-ascorbic acid is beneficial in preventing nickel-induced lipid alterations and hepatocellular damage.

Determination of the ascorbic acid content of two medicinal plants in Nigeria.

PubMed

H A, Okeri; P O, Alonge

2006-01-01

The fresh and dried leaves of two edible plants, Oldenlandia corymbosa and Dissotis rotundifolia have been assayed for their ascorbic acid content. They were found to be rich sources of ascorbic acid (vitamin C) when compared with some common garden fruits and vegetables. Students' t-test statistical analysis using INSTAT.EXE program for the results (mean+/-SEM) shows that there was no significant difference for the fresh leaves of the individual plants and also there is no significant difference for the dried leaves (P=0.05). However, there was significant difference between ascorbic acid content of the fresh and dried leaves of the same plant, obviously indicating that the fresh leaves contain more ascorbic acid than the dried leaves.

Ascorbic acid efflux and re-uptake in endothelial cells: maintenance of intracellular ascorbate.

PubMed

May, James M; Qu, Zhi-chao

2009-05-01

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 degrees C via a non-saturable process that was insensitive to anion transport inhibitors and thiol reagents. Oxidation of this extracellular ascorbate by ascorbate oxidase or ferricyanide enhanced apparent ascorbate efflux, suggesting that efflux of the vitamin was countered in part by its re-uptake on ascorbate transporters. Although basal ascorbate efflux was not calcium-dependent, increased entry of calcium into the cells enhanced ascorbate release. These results support the hypothesis that ascorbate efflux reflects trans-endothelial cell ascorbate movement out of the blood vessel.

Synthesis and characterization of cycloaliphatic hydrophilic polyurethanes, modified with l-ascorbic acid, as materials for soft tissue regeneration.

PubMed

Kucinska-Lipka, J; Gubanska, I; Strankowski, M; Cieśliński, H; Filipowicz, N; Janik, H

2017-06-01

In this paper we described synthesis and characteristic of obtained hydrophilic polyurethanes (PURs) modified with ascorbic acid (commonly known as vitamin C). Such materials may find an application in the biomedical field, for example in the regenerative medicine of soft tissues, according to ascorbic acid wide influence on tissue regeneration Flora (2009), Szymańska-Pasternak et al. (2011), Taikarimi and Ibrahim (2011), Myrvik and Volk (1954), Li et al. (2001), Cursino et al. (2005) . Hydrophilic PURs were obtained with the use of amorphous α,ω-dihydroxy(ethylene-butylene adipate) (dHEBA) polyol, 1,4-butanediol (BDO) chain extender and aliphatic 4,4'-methylenebis(cyclohexyl isocyanate) (HMDI). HMDI was chosen as a nontoxic diisocyanate, suitable for biomedical PUR synthesis. Modification with l-ascorbic acid (AA) was performed to improve obtained PUR materials biocompatibility. Chemical structure of obtained PURs was provided and confirmed by Fourier transform infrared spectroscopy (FTIR) and Proton nuclear magnetic resonance spectroscopy ( 1 HNMR). Differential scanning calorimetry (DSC) was used to indicate the influence of ascorbic acid modification on such parameters as glass transition temperature, melting temperature and melting enthalpies of obtained materials. To determine how these materials may potentially behave, after implementation in tissue, degradation behavior of obtained PURs in various chemical environments, which were represented by canola oil, saline solution, distilled water and phosphate buffered saline (PBS) was estimated. The influence of AA on hydrophilic-hydrophobic character of obtained PURs was established by contact angle study. This experiment revealed that ascorbic acid significantly improves hydrophilicity of obtained PUR materials and the same cause that they are more suitable candidates for biomedical applications. Good hemocompatibility characteristic of studied PUR materials was confirmed by the hemocompatibility test with

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

PubMed Central

May, James M.; Qu, Zhi-chao

2013-01-01

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. Oxidation of this extracellular ascorbate by ascorbate oxidase or ferricyanide enhanced apparent ascorbate efflux, suggesting that efflux of the vitamin was countered in part by its re-uptake on ascorbate transporters. Although basal ascorbate efflux was not calcium-dependent, increased entry of calcium into the cells enhanced ascorbate release. These results support the hypothesis that ascorbate efflux reflects trans-endothelial cell ascorbate movement out of the blood vessel. PMID:19148707

Regulation of embryonic neurotransmitter and tyrosine hydroxylase protein levels by ascorbic acid

PubMed Central

Meredith, M. Elizabeth; May, James M.

2013-01-01

Scope: Ascorbic acid (ascorbate) is required to recycle tetrahydrobiopterin, which is necessary for neurotransmitter synthesis by the rate-limiting enzymes tyrosine and tryptophan hydroxylases. We sought to determine whether ascorbate might regulate embryonic brain cortex monoamine synthesis utilizing transgenic mouse models with varying intracellular ascorbate levels. Methods and Results: In embryos lacking the sodium-dependent vitamin C transporter 2 (SVCT2), very low levels of brain ascorbate decreased cortex levels of norepinephrine and dopamine by approximately 33%, but had no effect on cortex serotonin or its metabolite, 5-hydroxyindole acetic acid. This decrease in ascorbate also led to a decrease in protein levels of tyrosine hydroxylase, but not of tryptophan hydroxylase. Increased cortex ascorbate in embryos carrying extra copies of the SVCT2 resulted in increased levels of dopamine and its metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC), as well as serotonin and 5-hydroxyindole acetic acid. Conclusion: The dependence of embryonic brain cortex neurotransmitter synthesis and tyrosine hydroxylase expression on intracellular ascorbate emphasizes the importance of receiving adequate ascorbate during development. PMID:24095796

[Enteral absoprtion of ascorbic acid in man after application of a micro-encapsulated retard preparation (author's transl)].

PubMed

Brenner, G

1975-07-11

Blood level determinations of ascorbic acid were carried out in 11 male probands after oral application of a new vitamin C retard preparation. In comparative tests the same probands received identical doses of a non retarded vitamine C preparations after a period without application of 2 weeks. The results obtained show that after application of the new vitamin C retard preparation the absorption of ascorbic acid is increased and thus a marked improvement of the bioavailability of vitamin C is attained as compared to the non retarded form.

Conversion of L-sorbosone to L-ascorbic acid by a NADP-dependent dehydrogenase in bean and spinach leaf. [Phaseolus vulgaris L. ; Spinacia oleracea L

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loewus, M.W.; Bedgar, D.L.; Saito, Kazumi

An NADP-dependent dehydrogenase catalyzing the conversion of L-sorbosone to L-ascorbic acid has been isolated from Phaseolus vulgaris L. and Spinacia oleracea L. and partially purified. It is stable at {minus}20{degree}C for up to 8 months. Molecular masses, as determined by gel filtration, were 21 and 29 kilodaltons for bean and spinach enzymes, respectively. K{sub m} for sorbosone were 12 {plus minus} 2 and 18 {plus minus} 2 millimolar and for NADP{sup +}, 0.14 {plus minus} 0.05 and 1.2 {plus minus} 0.5 millimolar, for bean and spinach, respectively. Lycorine, a purported inhibitor of L-ascorbic acid biosynthesis, had no effect on themore » reaction.« less

Collard, mustard and turnip greens: Effects of varieties and leaf position on concentrations of ascorbic acid, folate, B-carotene, lutein and phylloquinone

USDA-ARS?s Scientific Manuscript database

Leafy Brassica crops: collard (Brassica oleracea L.), mustard (B. juncea L.) and turnip (B. rapa) greens are important commercial and culinary vegetables; especially in the southern United States. However, almost no information on essential human-health vitamins [ascorbic acid (vit C), folate (vit...

Ascorbic acid interference in the measurement of serum biochemical parameters: in vivo and in vitro studies.

PubMed

Martinello, Flávia; da Silva, Edson Luiz

2006-04-01

To investigate the negative interference of ascorbic acid in serum biochemical tests in relation to the dose of vitamin C intake and to the time of blood collection. Healthy volunteers (n = 18) consumed daily doses of vitamin C (0.25-4.0 g) for 1 week and serum parameters were assayed prior to the experiment and on the eighth day of consumption. Blood samples were collected 4, 12 and 24 h after vitamin C intake. Serum levels of ascorbic acid increased significantly after vitamin C ingestion inhibiting urate and total bilirubin tests 4 and 12 h after intake (P < 0.01). A significant negative interference occurred up to 24 h after consumption of 4 g vitamin C for the urate test. In contrast, ingestion of vitamin C did not show interference in glucose, triglyceride and cholesterol tests. Addition of ascorbic acid to serum inhibited the urate test to a similar extent to that observed after vitamin C intake. However, after ingesting vitamin C, the interference for the bilirubin test was greater than that of the in vitro interference. Commonly taken doses of supplementary vitamin C interfered negatively with the serum urate test based on the Trinder method, and with bilirubin metabolism.

Genetic evidence for the role of GDP-mannose in plant ascorbic acid (vitamin C) biosynthesis

PubMed Central

Conklin, Patricia L.; Norris, Susan R.; Wheeler, Glen L.; Williams, Elizabeth H.; Smirnoff, Nicholas; Last, Robert L.

1999-01-01

Vitamin C (l-ascorbic acid; AsA) acts as a potent antioxidant and cellular reductant in plants and animals. AsA has long been known to have many critical physiological roles in plants, yet its biosynthesis is only currently being defined. A pathway for AsA biosynthesis that features GDP-mannose and l-galactose has recently been proposed for plants. We have isolated a collection of AsA-deficient mutants of Arabidopsis thaliana that are valuable tools for testing of an AsA biosynthetic pathway. The best-characterized of these mutants (vtc1) contains ≈25% of wild-type AsA and is defective in AsA biosynthesis. By using a combination of biochemical, molecular, and genetic techniques, we have demonstrated that the VTC1 locus encodes a GDP-mannose pyrophosphorylase (mannose-1-P guanyltransferase). This enzyme provides GDP-mannose, which is used for cell wall carbohydrate biosynthesis and protein glycosylation as well as for AsA biosynthesis. In addition to genetically defining the first locus involved in AsA biosynthesis, this work highlights the power of using traditional mutagenesis techniques coupled with the Arabidopsis Genome Initiative to rapidly clone physiologically important genes. PMID:10097187

Quasi elastic and inelastic neutron scattering study of vitamin C aqueous solutions

NASA Astrophysics Data System (ADS)

Migliardo, F.; Branca, C.; Magazù, S.; Migliardo, P.; Coppolino, S.; Villari, A.; Micali, N.

2002-02-01

In this paper, new results obtained by quasi elastic and inelastic neutron scattering experiments performed on vitamin C ( L-ascorbic acid)/H 2O mixtures are reported. The data analysis of the QENS measurements, by a separation of the diffusive dynamics of hydrated L-ascorbic acid from that of water, furnishes quantitative evidences of a random jump diffusion motion of vitamin C and shows that the water dynamics is strongly affected by the presence of L-ascorbic acid. Concerning the INS experiment, we are able, through the behaviour of neutron spectra across the glass transition temperature ( T g≈233 K for the vitamin C/water system), to collocate the investigated system in the Angell “strong-fragile” scheme.

Ascorbic acid, but not dehydroascorbic acid increases intracellular vitamin C content to decrease Hypoxia Inducible Factor -1 alpha activity and reduce malignant potential in human melanoma.

PubMed

Fischer, Adam P; Miles, Sarah L

2017-02-01

Accumulation of hypoxia inducible factor-1 alpha (HIF-1α) in malignant tissue is known to contribute to oncogenic progression and is inversely associated with patient survival. Ascorbic acid (AA) depletion in malignant tissue may contribute to aberrant normoxic activity of HIF-1α. While AA supplementation has been shown to attenuate HIF-1α function in malignant melanoma, the use of dehydroascorbic acid (DHA) as a therapeutic means to increase intracellular AA and modulate HIF-1α function is yet to be evaluated. Here we compared the ability of AA and DHA to increase intracellular vitamin C content and decrease the malignant potential of human melanoma by reducing the activity of HIF-1α. HIF-1α protein accumulation was evaluated by western blot and transcriptional activity was evaluated by reporter gene assay using a HIF-1 HRE-luciferase plasmid. Protein expressions and subcellular localizations of vitamin C transporters were evaluated by western blot and confocal imaging. Intracellular vitamin C content following AA, ascorbate 2-phosphate (A2P), or DHA supplementation was determined using a vitamin C assay. Malignant potential was accessed using a 3D spheroid Matrigel invasion assay. Data was analyzed by One or Two-way ANOVA with Tukey's multiple comparisons test as appropriate with p<0.05 considered significant. Melanoma cells expressed both sodium dependent vitamin C (SVCT) and glucose (GLUT) transporters for AA and DHA transport respectively, however advanced melanomas responded favorably to AA, but not DHA. Physiological glucose conditions significantly impaired intracellular vitamin C accumulation following DHA treatment. Consequently, A2P and AA, but not DHA treated cells demonstrated lower HIF-1α protein expression and activity, and reduced malignant potential. The ability of AA to regulate HIF-1α was dependent on SVCT2 function and SVCT2 was not significantly inhibited at pH representative of the tumor microenvironment. The use of ascorbic acid as an

Influence of temperature and brewing time of nettle (Urtica dioica L.) infusions on vitamin C content

PubMed

Wolska, Jolanta; Czop, Michał; Jakubczyk, Karolina; Janda, Katarzyna

Stinging nettle (Urtica dioica L.) can be found in temperate climate zones of Europe, Africa and America Nettle may be a source of nutritional ingredients, mineral salts, vitamins and antioxidants. The aim of the study was to determine the effect of temperature and brewing time Urtica dioica L. infusions from different parts of this plant on vitamin C (ascorbic acid) content. Infusions of nettle leaf, stem and root were prepared at room temperature, 50°C, 60°C, 70°C and 80°C for 10 minutes. Leaf infusions were also brewed for 5, 10, 15 and 20 minutes at initial water temperature of 60°C. The amount of vitamin C was determined by the spectrophotometric method. The best temperature of brewing nettle infusions, in terms of vitamin C concentration, is between 50 °C and 60 °C as it is sufficient to extract the substance, yet not high enough to destroy it. The optimal time of brewing appeared to be 10 minutes as the prolonged exposure to high temperature appeared to be detrimental for ascorbic acid as well.

Alleviation of ascorbic acid-induced gastric high acidity by calcium ascorbate in vitro and in vivo.

PubMed

Lee, Joon-Kyung; Jung, Sang-Hyuk; Lee, Sang-Eun; Han, Joo-Hui; Jo, Eunji; Park, Hyun-Soo; Heo, Kyung-Sun; Kim, Deasun; Park, Jeong-Sook; Myung, Chang-Seon

2018-01-01

Ascorbic acid is one of the most well-known nutritional supplement and antioxidant found in fruits and vegetables. Calcium ascorbate has been developed to mitigate the gastric irritation caused by the acidity of ascorbic acid. The aim of this study was to compare calcium ascorbate and ascorbic acid, focusing on their antioxidant activity and effects on gastric juice pH, total acid output, and pepsin secretion in an in vivo rat model, as well as pharmacokinetic parameters. Calcium ascorbate and ascorbic acid had similar antioxidant activity. However, the gastric fluid pH was increased by calcium ascorbate, whereas total acid output was increased by ascorbic acid. In the rat pylorus ligation-induced ulcer model, calcium ascorbate increased the gastric fluid pH without changing the total acid output. Administration of calcium ascorbate to rats given a single oral dose of 100 mg/kg as ascorbic acid resulted in higher plasma concentrations than that from ascorbic acid alone. The area under the curve (AUC) values of calcium ascorbate were 1.5-fold higher than those of ascorbic acid, and the C max value of calcium ascorbate (91.0 ng/ml) was higher than that of ascorbic acid (74.8 ng/ml). However, their T max values were similar. Thus, although calcium ascorbate showed equivalent antioxidant activity to ascorbic acid, it could attenuate the gastric high acidity caused by ascorbic acid, making it suitable for consideration of use to improve the side effects of ascorbic acid. Furthermore, calcium ascorbate could be an appropriate antioxidant substrate, with increased oral bioavailability, for patients with gastrointestinal disorders.

Alleviation of ascorbic acid-induced gastric high acidity by calcium ascorbate in vitro and in vivo

PubMed Central

Lee, Joon-Kyung; Jung, Sang-Hyuk; Lee, Sang-Eun; Han, Joo-Hui; Jo, Eunji; Park, Hyun-Soo; Heo, Kyung-Sun; Kim, Deasun

2018-01-01

Ascorbic acid is one of the most well-known nutritional supplement and antioxidant found in fruits and vegetables. Calcium ascorbate has been developed to mitigate the gastric irritation caused by the acidity of ascorbic acid. The aim of this study was to compare calcium ascorbate and ascorbic acid, focusing on their antioxidant activity and effects on gastric juice pH, total acid output, and pepsin secretion in an in vivo rat model, as well as pharmacokinetic parameters. Calcium ascorbate and ascorbic acid had similar antioxidant activity. However, the gastric fluid pH was increased by calcium ascorbate, whereas total acid output was increased by ascorbic acid. In the rat pylorus ligation-induced ulcer model, calcium ascorbate increased the gastric fluid pH without changing the total acid output. Administration of calcium ascorbate to rats given a single oral dose of 100 mg/kg as ascorbic acid resulted in higher plasma concentrations than that from ascorbic acid alone. The area under the curve (AUC) values of calcium ascorbate were 1.5-fold higher than those of ascorbic acid, and the Cmax value of calcium ascorbate (91.0 ng/ml) was higher than that of ascorbic acid (74.8 ng/ml). However, their Tmax values were similar. Thus, although calcium ascorbate showed equivalent antioxidant activity to ascorbic acid, it could attenuate the gastric high acidity caused by ascorbic acid, making it suitable for consideration of use to improve the side effects of ascorbic acid. Furthermore, calcium ascorbate could be an appropriate antioxidant substrate, with increased oral bioavailability, for patients with gastrointestinal disorders. PMID:29302210

Polymorphisms in sodium-dependent vitamin C transporter genes and plasma, aqueous humor and lens nucleus ascorbate concentrations in an ascorbate depleted setting.

PubMed

Senthilkumari, Srinivasan; Talwar, Badri; Dharmalingam, Kuppamuthu; Ravindran, Ravilla D; Jayanthi, Ramamurthy; Sundaresan, Periasamy; Saravanan, Charu; Young, Ian S; Dangour, Alan D; Fletcher, Astrid E

2014-07-01

We have previously reported low concentrations of plasma ascorbate and low dietary vitamin C intake in the older Indian population and a strong inverse association of these with cataract. Little is known about ascorbate levels in aqueous humor and lens in populations habitually depleted of ascorbate and no studies in any setting have investigated whether genetic polymorphisms influence ascorbate levels in ocular tissues. Our objectives were to investigate relationships between ascorbate concentrations in plasma, aqueous humor and lens and whether these relationships are influenced by Single Nucleotide Polymorphisms (SNPs) in sodium-dependent vitamin C transporter genes (SLC23A1 and SLC23A2). We enrolled sixty patients (equal numbers of men and women, mean age 63 years) undergoing small incision cataract surgery in southern India. We measured ascorbate concentrations in plasma, aqueous humor and lens nucleus using high performance liquid chromatography. SLC23A1 SNPs (rs4257763, rs6596473) and SLC23A2 SNPs (rs1279683 and rs12479919) were genotyped using a TaqMan assay. Patients were interviewed for lifestyle factors which might influence ascorbate. Plasma vitamin C was normalized by a log10 transformation. Statistical analysis used linear regression with the slope of the within-subject associations estimated using beta (β) coefficients. The ascorbate concentrations (μmol/L) were: plasma ascorbate, median and inter-quartile range (IQR), 15.2 (7.8, 34.5), mean (SD) of aqueous humor ascorbate, 1074 (545) and lens nucleus ascorbate, 0.42 (0.16) (μmol/g lens nucleus wet weight). Minimum allele frequencies were: rs1279683 (0.28), rs12479919 (0.30), rs659647 (0.48). Decreasing concentrations of ocular ascorbate from the common to the rare genotype were observed for rs6596473 and rs12479919. The per allele difference in aqueous humor ascorbate for rs6596473 was -217 μmol/L, p < 0.04 and a per allele difference in lens nucleus ascorbate of -0.085 μmol/g, p < 0

Human skeletal muscle ascorbate is highly responsive to changes in vitamin C intake and plasma concentrations.

PubMed

Carr, Anitra C; Bozonet, Stephanie M; Pullar, Juliet M; Simcock, Jeremy W; Vissers, Margreet Cm

2013-04-01

Vitamin C (ascorbate) is likely to be essential for skeletal muscle structure and function via its role as an enzyme cofactor for collagen and carnitine biosynthesis. Vitamin C may also protect these metabolically active cells from oxidative stress. We investigated the bioavailability of vitamin C to human skeletal muscle in relation to dietary intake and plasma concentrations and compared this relation with ascorbate uptake by leukocytes. Thirty-six nonsmoking men were randomly assigned to receive 6 wk of 0.5 or 2 kiwifruit/d, an outstanding dietary source of vitamin C. Fasting blood samples were drawn weekly, and 24-h urine and leukocyte samples were collected before intervention, after intervention, and after washout. Needle biopsies of skeletal muscle (vastus lateralis) were carried out before and after intervention. Baseline vastus lateralis ascorbate concentrations were ~16 nmol/g tissue. After intervention with 0.5 or 2 kiwifruit/d, these concentrations increased ~3.5-fold to 53 and 61 nmol/g, respectively. There was no significant difference between the responses of the 2 groups. Mononuclear cell and neutrophil ascorbate concentrations increased only ~1.5- and ~2-fold, respectively. Muscle ascorbate concentrations were highly correlated (P < 0.001) with dietary intake (R = 0.61) and plasma concentrations (R = 0.75) in the range from 5 to 80 μmol/L. Human skeletal muscle is highly responsive to vitamin C intake and plasma concentrations and exhibits a greater relative uptake of ascorbate than leukocytes. Thus, muscle appears to comprise a relatively labile pool of ascorbate and is likely to be prone to ascorbate depletion with inadequate dietary intake. This trial was registered at the Australian New Zealand Clinical Trials Registry (www.anzctr.org.au) as ACTRN12611000162910.

Ascorbic acid: Chemistry, biology and the treatment of cancer☆

PubMed Central

Du, Juan; Cullen, Joseph J.; Buettner, Garry R.

2013-01-01

Since the discovery of vitamin C, the number of its known biological functions is continually expanding. Both the names ascorbic acid and vitamin C reflect its antiscorbutic properties due to its role in the synthesis of collagen in connective tissues. Ascorbate acts as an electron-donor keeping iron in the ferrous state thereby maintaining the full activity of collagen hydroxylases; parallel reactions with a variety of dioxygenases affect the expression of a wide array of genes, for example via the HIF system, as well as via the epigenetic landscape of cells and tissues. In fact, all known physiological and biochemical functions of ascorbate are due to its action as an electron donor. The ability to donate one or two electrons makes AscH− an excellent reducing agent and antioxidant. Ascorbate readily undergoes pH-dependent autoxidation producing hydrogen peroxide (H2O2). In the presence of catalytic metals this oxidation is accelerated. In this review, we show that the chemical and biochemical nature of ascorbate contribute to its antioxidant as well as its prooxidant properties. Recent pharmacokinetic data indicate that intravenous (i.v.) administration of ascorbate bypasses the tight control of the gut producing highly elevated plasma levels; ascorbate at very high levels can act as prodrug to deliver a significant flux of H2O2 to tumors. This new knowledge has rekindled interest and spurred new research into the clinical potential of pharmacological ascorbate. Knowledge and understanding of the mechanisms of action of pharmacological ascorbate bring a rationale to its use to treat disease especially the use of i.v. delivery of pharmacological ascorbate as an adjuvant in the treatment of cancer. PMID:22728050

Theoretical study of the changes in the vibrational characteristics arising from the hydrogen bonding between Vitamin C ( L-ascorbic acid) and H 2O

NASA Astrophysics Data System (ADS)

Dimitrova, Yordanka

2006-02-01

The vibrational characteristics (vibrational frequencies, infrared intensities and Raman activities) for the hydrogen-bonded system of Vitamin C ( L-ascorbic acid) with five water molecules have been predicted using ab initio SCF/6-31G(d, p) calculations and DFT (BLYP) calculations with 6-31G(d, p) and 6-31++G(d, p) basis sets. The changes in the vibrational characteristics from free monomers to a complex have been calculated. The ab initio and BLYP calculations show that the complexation between Vitamin C and five water molecules leads to large red shifts of the stretching vibrations for the monomer bonds involved in the hydrogen bonding and very strong increase in their IR intensity. The predicted frequency shifts for the stretching vibrations from Vitamin C taking part in the hydrogen bonding are up to -508 cm -1. The magnitude of the wavenumber shifts is indicative of relatively strong OH···H hydrogen-bonded interactions. In the same time the IR intensity and Raman activity of these vibrations increase upon complexation. The IR intensity increases dramatically (up to 12 times) and Raman activity increases up to three times. The ab initio and BLYP calculations show, that the symmetric OH vibrations of water molecules are more sensitive to the complexation. The hydrogen bonding leads to very large red shifts of these vibrations and very strong increase in their IR intensity. The asymmetric OH stretching vibrations of water, free from hydrogen bonding are less sensitive to the complexation than the hydrogen-bonded symmetric O sbnd H stretching vibrations. The increases of the IR intensities for these vibrations are lower and red shifts are negligible.

Theoretical study on the adsorption and relative stability of conformers of L-ascorbic acid on γ - alumina (100) surface

NASA Astrophysics Data System (ADS)

Mozaffari Majd, M.; Dabbagh, H. A.; Farrokhpour, H.; Najafi Chermahini, A.

2017-11-01

The adsorption energies (Eads) and relative stabilities of selected conformers of the most stable tautomer of L-ascorbic acid (vitamin C) on the dehydroxylated γ-alumina (100) surface were calculated in both gas phase and solvent (water) using the density functional theory (DFT) method. The selected conformers were related to the different rotational angles of OH groups of L-ascorbic acid. The conformational analysis of bare tautomer in both gas and water showed that the conformer No.20 (conf. 20) and 13 (conf. 13) with the dihedral angles of H15sbnd O10sbnd C11sbnd C9 (-73°) and H20sbnd O19sbnd C9sbnd C11 (-135°) were the most stable and unstable conformers, respectively. The performed calculations in the presence of surface showed that the interaction of the conformers with the surface changes their relative stabilities and structures in both gas phase and water. The Ead of each conformer was calculated and it was determined that conf. 8 and conf. 16 have the highest value of Ead in the gas phase (-62.56 kcal/mol) and water (-54.44 kcal/mol), respectively. The optimized structure of each conformer on the surface and the number of hydrogen bonds between it and surface along with their bond lengths were determined.

A metabolic switch in brain: glucose and lactate metabolism modulation by ascorbic acid.

PubMed

Castro, Maite A; Beltrán, Felipe A; Brauchi, Sebastián; Concha, Ilona I

2009-07-01

In this review, we discuss a novel function of ascorbic acid in brain energetics. It has been proposed that during glutamatergic synaptic activity neurons preferably consume lactate released from glia. The key to this energetic coupling is the metabolic activation that occurs in astrocytes by glutamate and an increase in extracellular [K(+)]. Neurons are cells well equipped to consume glucose because they express glucose transporters and glycolytic and tricarboxylic acid cycle enzymes. Moreover, neuronal cells express monocarboxylate transporters and lactate dehydrogenase isoenzyme 1, which is inhibited by pyruvate. As glycolysis produces an increase in pyruvate concentration and a decrease in NAD(+)/NADH, lactate and glucose consumption are not viable at the same time. In this context, we discuss ascorbic acid participation as a metabolic switch modulating neuronal metabolism between rest and activation periods. Ascorbic acid is highly concentrated in CNS. Glutamate stimulates ascorbic acid release from astrocytes. Ascorbic acid entry into neurons and within the cell can inhibit glucose consumption and stimulate lactate transport. For this switch to occur, an ascorbic acid flow is necessary between astrocytes and neurons, which is driven by neural activity and is part of vitamin C recycling. Here, we review the role of glucose and lactate as metabolic substrates and the modulation of neuronal metabolism by ascorbic acid.

Role of ascorbic acid in stratum corneum lipid models exposed to UV irradiation.

PubMed

Trommer, Hagen; Böttcher, Roif; Pöppl, Andreas; Hoentsch, Joachim; Wartewig, Siegfried; Neubert, Reinhard H H

2002-07-01

The effects of ascorbic acid on Stratum corneum lipid models following ultraviolet irradiation were studied adding iron ions as transition metal catalysts. Lipid peroxidation was quantified by the thiobarbituric acid assay. The qualitative changes were studied on a molecular level by mass spectrometry. To elucidate the nature of free radical involvement we carried out electron paramagnetic resonance studies. The influence of ascorbic acid on the concentration of hydroxyl radicals was examined using the spin trapping technique. Moreover, we checked the vitamin's ability to react with stable radicals. Ascorbic acid was found to have prooxidative effects in all lipid systems in a concentration dependent manner. The degradation products of ascorbic acid after its prooxidative action were detected. The concentration of the hydroxyl radicals in the Fenton assay was decreased by ascorbic acid. The quantification assay of 2,2-diphenyl-1-picrylhydrazyl hydrate showed reduced concentration levels of the stable radical caused by ascorbic acid. Considering human skin and its constant exposure to UV light and oxygen, an increased pool of iron ions in irradiated skin and the depletion of co-antioxidants, the administration of ascorbic acid in cosmetic formulations or in sunscreens could unfold adverse effects among the Stratum corneum lipids.

A direct ascorbate fuel cell with an anion exchange membrane

NASA Astrophysics Data System (ADS)

Muneeb, Omar; Do, Emily; Tran, Timothy; Boyd, Desiree; Huynh, Michelle; Ghosn, Gregory; Haan, John L.

2017-05-01

Ascorbic Acid (Vitamin C) is investigated as a renewable alternative fuel for alkaline direct liquid fuel cells (DLFCs). The environmentally- and biologically-friendly compound, L-ascorbic acid (AA) has been modeled and studied experimentally under acidic fuel cell conditions. In this work, we demonstrate that ascorbic acid is a more efficient fuel in alkaline media than in acidic media. An operating direct ascorbate fuel cell is constructed with the combination of L-ascorbic acid and KOH as the anode fuel, air or oxygen as the oxidant, a polymer anion exchange membrane, metal or carbon black anode materials and metal cathode catalyst. Operation of the fuel cell at 60 °C using 1 M AA and 1 M KOH as the anode fuel and electrolyte, respectively, and oxygen gas at the cathode, produces a maximum power density of 73 mW cm-2, maximum current density of 497 mA cm-2 and an open circuit voltage of 0.90 V. This performance is significantly greater than that of an ascorbic acid fuel cell with a cation exchange membrane, and it is competitive with alkaline DLFCs fueled by alcohols.

Ascorbic Acid as a Standard for Iodometric Titrations. An Analytical Experiment for General Chemistry

NASA Astrophysics Data System (ADS)

Silva, Cesar R.; Simoni, Jose A.; Collins, Carol H.; Volpe, Pedro L. O.

1999-10-01

Ascorbic acid is suggested as the weighable compound for the standardization of iodine solutions in an analytical experiment in general chemistry. The experiment involves an iodometric titration in which iodine reacts with ascorbic acid, oxidizing it to dehydroascorbic acid. The redox titration endpoint is determined by the first iodine excess that is complexed with starch, giving a deep blue-violet color. The results of the titration of iodine solution using ascorbic acid as a calibration standard were compared with the results acquired by the classic method using a standardized solution of sodium thiosulfate. The standardization of the iodine solution using ascorbic acid was accurate and precise, with the advantages of saving time and avoiding mistakes due to solution preparation. The colorless ascorbic acid solution gives a very clear and sharp titration end point with starch. It was shown by thermogravimetric analysis that ascorbic acid can be dried at 393 K for 2 h without decomposition. This experiment allows general chemistry students to perform an iodometric titration during a single laboratory period, determining with precision the content of vitamin C in pharmaceutical formulations.

Human skeletal muscle ascorbate is highly responsive to changes in vitamin C intake and plasma concentrations123

PubMed Central

Bozonet, Stephanie M; Pullar, Juliet M; Simcock, Jeremy W; Vissers, Margreet CM

2013-01-01

Background: Vitamin C (ascorbate) is likely to be essential for skeletal muscle structure and function via its role as an enzyme cofactor for collagen and carnitine biosynthesis. Vitamin C may also protect these metabolically active cells from oxidative stress. Objective: We investigated the bioavailability of vitamin C to human skeletal muscle in relation to dietary intake and plasma concentrations and compared this relation with ascorbate uptake by leukocytes. Design: Thirty-six nonsmoking men were randomly assigned to receive 6 wk of 0.5 or 2 kiwifruit/d, an outstanding dietary source of vitamin C. Fasting blood samples were drawn weekly, and 24-h urine and leukocyte samples were collected before intervention, after intervention, and after washout. Needle biopsies of skeletal muscle (vastus lateralis) were carried out before and after intervention. Results: Baseline vastus lateralis ascorbate concentrations were ∼16 nmol/g tissue. After intervention with 0.5 or 2 kiwifruit/d, these concentrations increased ∼3.5-fold to 53 and 61 nmol/g, respectively. There was no significant difference between the responses of the 2 groups. Mononuclear cell and neutrophil ascorbate concentrations increased only ∼1.5- and ∼2-fold, respectively. Muscle ascorbate concentrations were highly correlated (P < 0.001) with dietary intake (R = 0.61) and plasma concentrations (R = 0.75) in the range from 5 to 80 μmol/L. Conclusions: Human skeletal muscle is highly responsive to vitamin C intake and plasma concentrations and exhibits a greater relative uptake of ascorbate than leukocytes. Thus, muscle appears to comprise a relatively labile pool of ascorbate and is likely to be prone to ascorbate depletion with inadequate dietary intake. This trial was registered at the Australian New Zealand Clinical Trials Registry (www.anzctr.org.au) as ACTRN12611000162910. PMID:23446899

Expression profiling of ascorbic acid-related genes during tomato fruit development and ripening and in response to stress conditions.

PubMed

Ioannidi, Eugenia; Kalamaki, Mary S; Engineer, Cawas; Pateraki, Irene; Alexandrou, Dimitris; Mellidou, Ifigeneia; Giovannonni, James; Kanellis, Angelos K

2009-01-01

L-ascorbate (the reduced form of vitamin C) participates in diverse biological processes including pathogen defence mechanisms, and the modulation of plant growth and morphology, and also acts as an enzyme cofactor and redox status indicator. One of its chief biological functions is as an antioxidant. L-ascorbate intake has been implicated in the prevention/alleviation of varied human ailments and diseases including cancer. To study the regulation of accumulation of this important nutraceutical in fruit, the expression of 24 tomato (Solanum lycopersicon) genes involved in the biosynthesis, oxidation, and recycling of L-ascorbate during the development and ripening of fruit have been characterized. Taken together with L-ascorbate abundance data, the results show distinct changes in the expression profiles for these genes, implicating them in nodal regulatory roles during the process of L-ascorbate accumulation in tomato fruit. The expression of these genes was further studied in the context of abiotic and post-harvest stress, including the effects of heat, cold, wounding, oxygen supply, and ethylene. Important aspects of the hypoxic and post-anoxic response in tomato fruit are discussed. The data suggest that L-galactose-1-phosphate phosphatase could play an important role in regulating ascorbic acid accumulation during tomato fruit development and ripening.

[The impact of ascorbic acid on the concentrations of antioxidative vitamins in the plasma of patients with non-small cell lung cancer undergoing first-line chemotherapy].

PubMed

Tokarski, Sławomir; Rutkowski, Maciej; Godala, Małgorzata; Mejer, Anna; Kowalski, Jan

2013-09-01

One of the main after-effects of chemotherapy used in cancer treatment is an augmented production of reactive oxygen species (ROS). In turn ROS become a source of unwanted side effects of chemotherapy, often forcing the discontinuation of the therapy. Ascorbic acid (vitamin C), being an antioxidant, can strengthen the antioxidative barrier of an organism. The aim of the study was an assessment of the concentrations of A, C and E vitamins in the plasma of NSCLC patients undergoing chemotherapy supplemented with vitamin C. 25 first-line chemotherapy patients with inoperable NSCLC, including 19 men and 6 women aged between 37-73 years (average age 60.1 +/- 8.8 years) have undergone the examination. Their chemotherapy has been supplemented with ascorbic acid (vitamin C dose of 600 mg per 24 hours). Control group consisted of 24 healthy individuals, including 18 men and 6 women aged between 49-71 years (average age 59.5 +/- 6.6 years). In cancer patients the concentration of A, C and E vitamins was assessed by spectrophotometry using T60V spectrophotometer (PG Instruments) before and after first-line chemotherapy which was supplemented with vitamin C. In control group the concentrations of antioxidative vitamins was assessed only once. In comparison to the control group the concentrations of the A, C and E vitamins in the plasma of NSCLC patients was significantly lower (p < 0.05). After 6 weeks of chemotherapy supplemented with vitamin C a significant rise of concentrations (p < 0.05) of all the vitamins tested for was observed. The biggest rise was noted for vitamin C (99.8%). The supplementation of the chemotherapy of NSCLC patients with C vitamin leads to rise of the low concentrations of A, C and E vitamins in the plasma. This suggests strengthening of the antioxidative barrier in patients.

Gender difference following high cholesterol diet induced renal injury and the protective role of rutin and ascorbic acid combination in Wistar albino rats

PubMed Central

2012-01-01

Background An increased interest is given to the impact of high fat diet on health worldwide. Abnormalities in lipid metabolism induced by high cholesterol diet (HCD) were reported to exacerbate renal diseases via oxidative stress pathways. Rutin and ascorbic acid showed a protective role against oxidative stress-mediated diseases. Furthermore, both lipid metabolism and tissue response to oxidative stress damage was found to vary according to animal gender. Thus, the objective of this work was to examine possible gender-related differences and the possible protective effects of rutin and ascorbic acid supplementation on high cholesterol diet induced nephrotoxicity. Methods 96 young male and female Wistar albino rats were used. HCD supplemented animals were treated with rutin alone or in combination with ascorbic acid for 6 weeks. Creatinine plasma level was estimated. Furthermore, kidney levels of nucleic acids, total protein, malondialdehyde (MDA), reduced glutathione (GSH), total cholesterol, and triglycerides were determined. Finally, kidney tissues were used for histopathological examination. Results HCD supplementation decreased kidney level of nucleic acids, which was more prominent in female animals. Both vitamin combination significantly attenuated HCD induced decrease in nucleic acids. Moreover, kidney level of MDA was significantly altered by HCD in both genders, which was inhibited by rutin and ascorbic acid alone or in combination in male groups and by both vitamins in female groups. There was a reduction in kidney level of GSH by HCD, especially in male groups, which was attenuated by rutin and ascorbic acid combination. Kidney levels of total cholesterol and triglycerides were significantly increased by HCD supplementation in both genders. Coadministration with rutin and/or ascorbic acid protected from such increase, which was more obvious in both vitamins combination. Histopathological investigation supported vitamins protective effect, which was

Gender difference following high cholesterol diet induced renal injury and the protective role of rutin and ascorbic acid combination in Wistar albino rats.

PubMed

Al-Rejaie, Salim Salih; Abuohashish, Hatem Mustafa; Alkhamees, Osama Abdelrahman; Aleisa, Abdulaziz Mohammed; Alroujayee, Abdulaziz S

2012-03-16

An increased interest is given to the impact of high fat diet on health worldwide. Abnormalities in lipid metabolism induced by high cholesterol diet (HCD) were reported to exacerbate renal diseases via oxidative stress pathways. Rutin and ascorbic acid showed a protective role against oxidative stress-mediated diseases. Furthermore, both lipid metabolism and tissue response to oxidative stress damage was found to vary according to animal gender. Thus, the objective of this work was to examine possible gender-related differences and the possible protective effects of rutin and ascorbic acid supplementation on high cholesterol diet induced nephrotoxicity. 96 young male and female Wistar albino rats were used. HCD supplemented animals were treated with rutin alone or in combination with ascorbic acid for 6 weeks. Creatinine plasma level was estimated. Furthermore, kidney levels of nucleic acids, total protein, malondialdehyde (MDA), reduced glutathione (GSH), total cholesterol, and triglycerides were determined. Finally, kidney tissues were used for histopathological examination. HCD supplementation decreased kidney level of nucleic acids, which was more prominent in female animals. Both vitamin combination significantly attenuated HCD induced decrease in nucleic acids. Moreover, kidney level of MDA was significantly altered by HCD in both genders, which was inhibited by rutin and ascorbic acid alone or in combination in male groups and by both vitamins in female groups. There was a reduction in kidney level of GSH by HCD, especially in male groups, which was attenuated by rutin and ascorbic acid combination. Kidney levels of total cholesterol and triglycerides were significantly increased by HCD supplementation in both genders. Coadministration with rutin and/or ascorbic acid protected from such increase, which was more obvious in both vitamins combination. Histopathological investigation supported vitamins protective effect, which was more prominent in male

Enzymatic synthesis of 3-O-α-maltosyl-l-ascorbate using an engineered cyclodextrin glucanotransferase.

PubMed

Ahn, Hee-Jeong; Li, Chao; Cho, Hye-Bin; Park, Sunghoon; Chang, Pahn-Shick; Kim, Young-Wan

2015-02-15

A mutant derived from a cyclodextrin glucantransferase with an alanine residue as its acid/base catalyst residue (CGT-E284A) catalyzed regioselective glycosylation at 3-OH of l-ascorbic acid using α-maltosyl fluoride (αG2F) and l-ascorbic acid as the donor and acceptor, respectively, yielding 3-O-α-maltosyl-l-ascorbate (AA3αG2). The optimum conditions were determined by high-performance liquid chromatography analysis with 20mM αG2F and 40mM l-ascorbic acid as the substrates at pH 7.5 and 25°C with 1mg/ml of the enzyme for 24h. Calcium ions bound in CGT-E284A played an important role in the transglycosylation. CGT-E284A exhibited typical saturation kinetic behaviour for αG2F at a fixed acceptor concentration (40mM), and substrate inhibition by l-ascorbic acid was observed at high l-ascorbic acid concentrations (>60mM). AA3αG2 was isolated from a preparative scale reaction with a yield of 29%, and it showed extremely high stability under oxidative conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Urinary and plasma oxalate during ingestion of pure ascorbic acid: a re-evaluation.

PubMed

Fituri, N; Allawi, N; Bentley, M; Costello, J

1983-01-01

Daily ingestion of 8 g of pure ascorbic acid by 8 normal subjects for 7 days did not, in contrast to previous reports in the literature, significantly alter urinary or plasma oxalate during or after ingestion. When urine with raised ascorbate values was heated at 100 degrees C for 30 min, a significant increase in urinary oxalate concentration was observed. Plasma ascorbate reached a mean value during ingestion of 3.3 mg/100 ml. Urinary citrate excretion significantly decreased during the first 4 days of ascorbic acid ingestion; however, the urinary inhibitory activity of calcium oxalate crystal growth was not significantly altered. Urinary and serum urate as well as urinary calcium and magnesium were unaltered by ingestion of the vitamin supplement.

Impact of liposomal encapsulation on degradation of anthocyanins of black carrot extract by adding ascorbic acid.

PubMed

Guldiken, Burcu; Gibis, Monika; Boyacioglu, Dilek; Capanoglu, Esra; Weiss, Jochen

2017-03-22

Black carrot anthocyanins are known to be relatively stable because they contain acylated anthocyanins. The degradation of vitamin C (l-ascorbic acid) on anthocyanins is a known fact in beverage systems. In this study, the effects of various liposomal systems, including black carrot extract (0.1%, 0.2%, 0.4% w/w) and lecithin (1%, 2%, 4% w/w), on the color and degradation of anthocyanin in different ascorbic acid (0.01%, 0.025%, 0.05%, 0.1% w/w) concentrations were examined via UV/VIS spectroscopy and visual control of the color. The physical characteristics of the liposomal systems resulted in particle diameters of 41-46 nm and zeta-potentials of (-23)-(-20) mV. The encapsulation efficiencies of the liposomal systems increased up to 50% with increasing lecithin concentrations. The encapsulation of black carrot extract in liposomes enhanced the color and stability of the anthocyanins during storage. This study showed that the degradation of anthocyanins due to ascorbic acid can be reduced by liposomes in aqueous solutions.

Combined effect of selenium and ascorbic acid on alcohol induced hyperlipidemia in male guinea pigs.

PubMed

Asha, G S; Indira, M

2004-02-01

Alcoholics usually suffer from malnutrition and are especially deficient in micronutrients like vitamin C, selenium and Zn. In the present study, combined effects of selenium and ascorbic acid on alcohol-induced hyperlipidemia were studied in guinea pigs. Four groups of male guinea pigs were maintained for 45 days as follows: control (1 mg ascorbate (AA)/100 g body mass/day), ethanol (900 mg ethanol/100 g body mass + 1 mg AA/100 g body mass/day), selenium+ascorbic acid [(25 mg AA + 0.05 mg Se)/100 g body mass/day], ethanol+selenium+ascorbic acid [(25 mg AA + 0.05 mg Se + 900 mg ethanol)/100 g body mass/day]. Co-administration of selenium and ascorbic acid along with alcohol reduced the concentration of all lipids, as also evidenced from the decreased activities of hydroxymethylglutaryl-CoA reductase and enhanced activities of plasma lecithin cholesterol acyl transferase and lipoprotein lipase. Concentrations of bile acids were increased. We conclude that the supplementation of Se and ascorbic acid reduced alcohol induced hyperlipidemia, by decreased synthesis and increased catabolism.

Kinetic thermal degradation of vitamin C during microwave drying of okra and spinach.

PubMed

Dadali, Gökçe; Ozbek, Belma

2009-01-01

In this present study, the effect of microwave output power and sample amount on vitamin C loss in okra (Hibiscus esculenta L.) and spinach (Spinacia oleracea L.) were investigated using the microwave drying technique. The procedure is based on the reaction between l-ascorbic acid (vitamin C) and 2,6-dichloroindophenol. The proposed method was applied successfully to both okra and spinach for the determination of ascorbic acid (vitamin C) content. It was observed that as the microwave output power increased or as the sample amount decreased, the vitamin C in okra and spinach decreased as well. The activation energy for degradation of vitamin C for both okra and spinach was calculated using an exponential expression based on the Arrhenius equation.

Kinetics of browning and correlations between browning degree and pyrazine compounds in l-ascorbic acid/acidic amino acid model systems.

PubMed

Yu, Ai-Nong; Zhou, Yong-Yan; Yang, Yi-Ni

2017-04-15

The kinetics of browning and the correlation between browning products (BPs) and pyrazine compounds were investigated by heating equimolar l-ascorbic acid (ASA)/acidic amino acids under weak alkaline conditions at 120-150°C for 10-120min. The formations of BPs and pyrazine compounds from the reaction were monitored by UV-vis and SPME-GC-FID, respectively. The formation of BPs in both ASA/l-glutamic acid and ASA/l-aspartic acid model reaction systems followed zero order reaction kinetics with activation energies (E a ) of 90.13 and 93.38kJ/mol, respectively. ASA/l-aspartic acid browned at a slightly higher rate than ASA/l-glutamic acid. The total concentration of pyrazine compounds was highly and positively correlated with that of BPs. Based on the observed kinetic data, the formation mechanisms of BPs and pyrazine compounds were proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Localization of ascorbic acid, ascorbic acid oxidase, and glutathione in roots of Cucurbita maxima L.

PubMed

Liso, Rosalia; De Tullio, Mario C; Ciraci, Samantha; Balestrini, Raffaella; La Rocca, Nicoletta; Bruno, Leonardo; Chiappetta, Adriana; Bitonti, Maria Beatrice; Bonfante, Paola; Arrigoni, Oreste

2004-12-01

To understand the function of ascorbic acid (ASC) in root development, the distribution of ASC, ASC oxidase, and glutathione (GSH) were investigated in cells and tissues of the root apex of Cucubita maxima. ASC was regularly distributed in the cytosol of almost all root cells, with the exception of quiescent centre (QC) cells. ASC also occurred at the surface of the nuclear membrane and correspondingly in the nucleoli. No ASC could be observed in vacuoles. ASC oxidase was detected by immunolocalization mainly in cell walls and vacuoles. This enzyme was particularly abundant in the QC and in differentiating vascular tissues and was absent in lateral root primordia. Administration of the ASC precursor L-galactono-gamma-lactone markedly increased ASC content in all root cells, including the QC. Root treatment with the ASC oxidized product, dehydroascorbic acid (DHA), also increased ASC content, but caused ASC accumulation only in peripheral tissues, where DHA was apparently reduced at the expense of GSH. The different pattern of distribution of ASC in different tissues and cell compartments reflects its possible role in cell metabolism and root morphogenesis.

Effects of vitamin C on percent neurulation, hatch, growth, and survival of hybrid catfish challenged with virulent Edwardsiella ictaluri

USDA-ARS?s Scientific Manuscript database

Vitamin C (ascorbic acid) is an essential micronutrient involved in several physiological processes such as growth, reproduction, and immune response. Requirements of vitamin C during gamete formation and early life stages of catfish are not known. Ascorbic acid (1 mg/mL/kg BW) was administered in...

Ascorbic Acid Prevents VEGF-induced Increases in Endothelial Barrier Permeability

PubMed Central

Ulker, Esad; Parker, William H.; Raj, Amita; Qu, Zhi-chao; May, James M.

2015-01-01

Vascular endothelial growth factor (VEGF) increases endothelial barrier permeability, an effect that may contribute to macular edema in diabetic retinopathy. Since vitamin C, or ascorbic acid, can tighten the endothelial permeability barrier, we examined whether it could prevent the increase in permeability due to VEGF in human umbilical vein endothelial cells (HUVECs). As previously observed, VEGF increased HUVEC permeability to radiolabeled inulin within 60 min in a concentration-dependent manner. Loading the cells with increasing concentrations of ascorbate progressively prevented the leakage caused by 100 ng/ml VEGF, with a significant inhibition at 13 μM and complete inhibition at 50 μM. Loading cells with 100 μM ascorbate also decreased basal generation of reactive oxygen species and prevented the increase caused by both 100 ng/ml VEGF. VEGF treatment decreased intracellular ascorbate by 25%, thus linking ascorbate oxidation to its prevention of VEGF-induced barrier leakage. The latter was blocked by treating the cells with 60 μM L-NAME (but not D-NAME) as well as by 30 μM sepiapterin, a precursor of tetrahydrobiopterin that is required for proper function of endothelial nitric oxide synthase (eNOS). These findings suggest that VEGF-induced barrier leakage uncouples eNOS. Ascorbate inhibition of the VEGF effect could thus be due either to scavenging superoxide or to peroxynitrite generated by the uncoupled eNOS, or more likely to its ability to recycle tetrahydrobiopterin, thus avoiding enzyme uncoupling in the first place. Ascorbate prevention of VEGF-induced increases in endothelial permeability opens the possibility that its repletion could benefit diabetic macular edema. PMID:26590088

An Inquiry into the Effect of Heating on Ascorbic Acid

ERIC Educational Resources Information Center

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…

Indirect potentiometric titration of ascorbic acid in pharmaceutical preparations using copper based mercury film electrode.

PubMed

Abdul Kamal Nazer, Meeran Mohideen; Hameed, Abdul Rahman Shahul; Riyazuddin, Patel

2004-01-01

A simple and rapid potentiometric method for the estimation of ascorbic acid in pharmaceutical dosage forms has been developed. The method is based on treating ascorbic acid with iodine and titration of the iodide produced equivalent to ascorbic acid with silver nitrate using Copper Based Mercury Film Electrode (CBMFE) as an indicator electrode. Interference study was carried to check possible interference of usual excipients and other vitamins. The precision and accuracy of the method was assessed by the application of lack-of-fit test and other statistical methods. The results of the proposed method and British Pharmacopoeia method were compared using F and t-statistical tests of significance.

The effect of L-ascorbic acid and/or tocopherol supplementation on electrophysiological parameters of the colon of rats chronically exposed to lead

PubMed Central

Kosik-Bogacka, Danuta I.; Baranowska-Bosiacka, Irena; Marchlewicz, Mariola; Kolasa, Agnieszka; Jakubowska, Katarzyna; Olszewska, Maria; Łanocha, Natalia; Wiernicki, Ireneusz; Millo, Barbara; Wiszniewska, Barbara; Chlubek, Dariusz

2011-01-01

Summary Background The aim of this study was to assess the effect of diet supplementation with L-ascorbic acid (500 mg/L), tocopherol (3 mg/kg b.w.), and/or a water soluble analog of tocopherol (Trolox) (48 mg/L) on ion transport in the colon of rats subjected to a chronic exposure (9 months) to 0.1% lead acetate in drinking water. Material/Methods The electrophysiological parameters of the colon wall were measured with Ussing methods. Lead content in the whole blood was analyzed by graphite furnace atomic absorption spectrometry (GFAAS) using Zeeman correction. L-ascorbic acid and tocopherol in plasma was measured by high performance liquid chromatography. Immunohistochemical reaction was carried out for visualization of occludin, the intracellular tight junction protein. Results We showed a strong inhibitory effect of lead on the electrophysiological parameters, changes in intestinal permeability, disappearance of junctional occludin, decreased amount of mucus covering the colon surface, and the accumulation of PAS-positive substance in the apical region of the cytoplasm in the absorptive cells. Conclusions Supplementation with tocopherol or Trolox did not exert a beneficial influence on the studied parameters. L-ascorbic acid positively influenced the examined electrophysiological parameters, as it cancelled the inhibitory influence of lead on ion transport in the rat colon. L-ascorbic acid also protected against tight junction disruption of epithelial cells in the colon of the lead-treated rats. A similar effect was observed in the group of rats receiving lead and supplemented with L-ascorbic acid plus Trolox. PMID:21169903

Protective role of L-ascorbic acid, N-acetylcysteine and apocynin on neomycin-induced hair cell loss in zebrafish.

PubMed

Wu, Chia-Yen; Lee, Han-Jung; Liu, Chi-Fang; Korivi, Mallikarjuna; Chen, Hwei-Hsien; Chan, Ming-Huan

2015-03-01

Hair cells are highly sensitive to environmental insults and other therapeutic drugs. The adverse effects of drugs such as aminoglycosides can cause hair cell death and lead to hearing loss and imbalance. The objective of the present study was to evaluate the protective activity of L-ascorbic acid, N-acetylcysteine (NAC) and apocynin on neomycin-induced hair cell damage in zebrafish (Danio rerio) larvae at 5 days post fertilization (dpf). Results showed that the loss of hair cells within the neuromasts of the lateral lines after neomycin exposure was evidenced by a significantly lower number of neuromasts labeled with fluorescent dye FM1-43FX observed under a microscope. Co-administration with L-ascorbic acid, NAC and apocynin protected neomycin-induced hair cell loss within the neuromasts. Moreover, these three compounds reduced the production of reactive oxygen species (ROS) in neuromasts exposed to neomycin, indicating that their antioxidant action is involved. In contrast, the neuromasts were labeled with specific fluorescent dye Texas-red conjugated with neomycin to detect neomycin uptake. Interestingly, the uptake of neomycin into hair cells was not influenced by these three antioxidant compounds. These data imply that prevention of hair cell damage against neomycin by L-ascorbic acid, NAC and apocynin might be associated with inhibition of excessive ROS production, but not related to modulating neomycin uptake. Our findings conclude that L-ascorbic acid, NAC and apocynin could be used as therapeutic drugs to protect aminoglycoside-induced listening impairment after further confirmatory studies. Copyright © 2014 John Wiley & Sons, Ltd.

Electrocatalytic simultaneous determination of ascorbic acid, uric acid and L-Cysteine in real samples using quercetin silver nanoparticles-graphene nanosheets modified glassy carbon electrode

NASA Astrophysics Data System (ADS)

Zare, Hamid R.; Jahangiri-Dehaghani, Fahime; Shekari, Zahra; Benvidi, Ali

2016-07-01

By immobilizing of quercetin at the surface of a glassy carbon electrode modified with silver nanoparticles and graphene nanosheets (Q-AgNPs-GNs-GCE) a new sensor has been fabricated. The cyclic voltammogram of Q-AgNPs-GNs-GCE shows a stable redox couple with surface confined characteristics. Q-AgNPs-GNs-GCE demonstrated a high catalytic activity for L-Cysteine (L-Cys) oxidation. Results indicated that L-Cys peak potential at Q-AgNPs-GNs-GCE shifted to less positive values compared to GNs-GCE or AgNPs-GCE. Also, the kinetic parameters such as the electron transfer coefficient,, and the heterogeneous electron transfer rate constant, k‧, for the oxidation of L-Cys at the Q-AgNPs-GNs-GCE surface were estimated. In differential pulse voltammetric determination, the detection limit of L-Cys was obtained 0.28 μM, and the calibration plots were linear within two ranges of 0.9-12.4 μM and 12.4-538.5 μM of L-Cys. Also, the proposed modified electrode is used for the simultaneous determinations of ascorbic acid (AA), uric acid (UA), and L-Cys. Finally, this study has demonstrated the practical analytical utility of the sensor for determination of AA in vitamin C tablet, L-Cys in a milk sample and UA in a human urine sample.

Enhanced production of mineralized nodules and collagenous proteins in vitro by calcium ascorbate supplemented with vitamin C metabolites.

PubMed

Rowe, D J; Ko, S; Tom, X M; Silverstein, S J; Richards, D W

1999-09-01

Vitamin C or ascorbate is important in wound healing due to its essential role in collagen synthesis. To study wound healing in the periodontium, cells adherent to expanded polytetrafluoroethylene (ePTFE) augmentation membranes, recovered from edentulous ridge augmentation procedures, have been established in culture in our laboratories. The objective of this study was to determine whether treatment of these cells with a calcium ascorbate, which contains vitamin C metabolites (metabolite-supplemented ascorbate), would increase the production of collagenous protein and mineralized tissue in vitro, as compared to unsupplemented calcium ascorbate (ascorbate). Cells derived from ePTFE membranes were cultured with beta-glycerophosphate and the test agents for 2 to 5 weeks, and the surface areas of the cell cultures occupied by mineralized nodules were measured using computerized image analysis. One experiment tested the effects of calcium threonate, one of the vitamin C metabolites in metabolite-supplemented ascorbate. Incorporation of radioactive proline and glycine was used as a measure of total protein (radioactivity precipitated by trichloracetic acid) and collagenase-digestible protein (radioactivity released by collagenase digestion.) Co-localization of collagen and fibronectin was examined by immunofluorescence. In vitro treatment of these cells with metabolite-supplemented ascorbate increased the area of the cell cultures occupied by mineralized nodules after 5 weeks. Cell cultures treated with metabolite-supplemented ascorbate also exhibited significant increases in total protein. The increase in collagenous proteins in these cultures accounted for 85% of the increase in total protein. The greatest difference between treatment groups was observed in the cell-associated fraction containing the extracellular matrix. The additional collagen exhibited normal co-distribution with fibronectin. In cultures treated with ascorbate spiked with calcium threonate, the area

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

PubMed Central

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. PMID:28245268

Targeted antitumoral dehydrocrotonin nanoparticles with L-ascorbic acid 6-stearate.

PubMed

Frungillo, Lucas; Martins, Dorival; Teixeira, Sérgio; Anazetti, Maristela Conti; Melo, Patrícia da Silva; Durán, Nelson

2009-12-01

Tumoral cells are known to have a higher ascorbic acid uptake than normal cells. Therefore, the aim of this study was to obtain polymeric nanoparticles containing the antitumoral compound trans-dehydrocrotonin (DHC) functionalized with L-ascorbic acid 6-stearate (AAS) to specifically target this system tumoral cells. Nanoparticle suspensions (NP-AAS-DHC) were prepared by the nanoprecipitation method. The systems were characterized for AAS presence by thin-layer chromatography and for drug loading (81-88%) by UV-Vis spectroscopy. To further characterize these systems, in vitro release kinetics, size distribution (100-140 nm) and Zeta potential by photon-correlation spectroscopic method were used. In vitro toxicity against HL60 cells was evaluated by tetrazolium reduction and Trypan blue exclusion assays. Cell death by apoptosis was quantified and characterized by flow cytometry and caspase activity. Zeta potential analyses showed that the system has a negatively charged outer surface and also indicate that AAS is incorporated on the external surface of the nanoparticles. In vitro release kinetics assay showed that DHC loaded in nanoparticles had sustained release behavior. In vitro toxicity assays showed that NP-AAS-DHC suspension was more effective as an antitumoral than free DHC or NP-DHC and increased apoptosis induction by receptor-mediated pathway. 2009 Wiley-Liss, Inc. and the American Pharmacists Association

Gold Electrodes Modified with Self-Assembled Monolayers for Measuring L-Ascorbic Acid: An Undergraduate Analytical Chemistry Laboratory Experiment

ERIC Educational Resources Information Center

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…

A highly sensitive kinetic spectrophotometric method for the determination of ascorbic Acid in pharmaceutical samples.

PubMed

Shishehbore, Masoud Reza; Aghamiri, Zahra

2014-01-01

In this study, a new reaction system for quantitative determination of ascorbic acid was introduced. The developed method is based on inhibitory effect of ascorbic acid on the Orange G-bromate system. The change in absorbance was followed spectrophotometrically at 478 nm. The dependence of sensitivity on the reaction variables including reagents concentration, temperature and time was investigated. Under optimum experimental conditions, calibration curve was linear over the range 0.7 - 33.5 μg mL(-1) of ascorbic acid including two linear segments and the relative standard deviations (n = 6) for 5.0 and 20.0 μg mL(-1) of ascorbic acid were 1.08 and 1.02%, respectively. The limit of detection was 0.21 μg mL(-) (1) of ascorbic acid. The effect of diverse species was also investigated. The developed method was successfully applied for the determination of ascorbic acid in pharmaceutical samples. The results were in a good agreement with those of reference method.

Properties of L-ascorbic acid in water and binary aqueous mixtures of D-glucose and D-fructose at different temperatures

NASA Astrophysics Data System (ADS)

Sharma, Ravi; Thakur, R. C.; Sani, Balwinder; Kumar, Harsh

2017-12-01

Using density and sound velocity partial molar volumes, partial molar adiabatic compressibilities, partial molar expansibilities and structure of L-ascorbic acid have been determined in water and aqueous mixtures of D-glucose and D-fructose at different concentrations and temperatures. Masson's equation was used to analyze the measured data. The obtained parameters have been interpreted in terms of solute-solute and solute-solvent interactions. It is found that the L-ascorbic acid acts as structure breaker in water as well in binary studied mixtures.

Abscisic acid and pyrabactin improve vitamin C contents in raspberries.

PubMed

Miret, Javier A; Munné-Bosch, Sergi

2016-07-15

Abscisic acid (ABA) is a plant growth regulator with roles in senescence, fruit ripening and environmental stress responses. ABA and pyrabactin (a non-photosensitive ABA agonist) effects on red raspberry (Rubus idaeus L.) fruit development (including ripening) were studied, with a focus on vitamin and antioxidant composition. Application of ABA and/or pyrabactin just after fruit set did not affect the temporal pattern of fruit development and ripening; neither provitamin A (carotenoids) nor vitamin E contents were modified. In contrast, ABA and pyrabactin altered the vitamin C redox state at early stages of fruit development and more than doubled vitamin C contents at the end of fruit ripening. These were partially explained by changes in ascorbate oxidation and recycling. Therefore, ABA and pyrabactin applications may be used to increase vitamin C content of ripe fruits, increasing fruit quality and value. However, treatments containing pyrabactin-combined with ABA or alone-diminished protein content, thus partially limiting its potential applicability. Copyright © 2016 Elsevier Ltd. All rights reserved.

Skin penetration and retention of L-ascorbic acid 2-phosphate using multilamellar vesicles.

PubMed

Yoo, Juno; Shanmugam, Srinivasan; Song, Chung-Kil; Kim, Dae-Duk; Choi, Han-Gon; Yong, Chul-Soon; Woo, Jong-Soo; Yoo, Bong Kyu

2008-12-01

Transdermal formulation of L-ascorbic acid 2-phosphate magnesium salt (A2P) was prepared using multilamellar vesicles (MLV). A2P was either physically mixed with or entrapped into three different MLVs of neutral, cationic, and anionic liposome vesicles. For the preparation of neutral MLVs, phosphatidylcholine (PC) and cholesterol (CH) were used. For cationic and anionic MLVs, dioleoyl-trimethylammonium-propane and dimyristoyl glycerophosphate were added as surface charge inducers, respectively, in addition to PC and CH. Particle size of the three A2P-loaded MLVs was submicron, and polydispersity index revealed homogenous distribution of the prepared MLVs except neutral ones. Skin penetration study with hairless mouse skin showed that both physical mixtures of A2P with empty MLVs and A2P-loaded MLVs increased penetration of the drug compared to aqueous A2P solution. During the penetration, however, significant amount of the drug was metabolized into L-ascorbic acid, which has no beneficial effect on stimulation of hair growth. Out of the physical mixtures and A2P-loaded MLVs tested, physical mixture of A2P with empty cationic MLV resulted in the greatest skin penetration and retention in hairless mouse skin.

Mechanism of action of vitamin C in sepsis: Ascorbate modulates redox signaling in endothelium

PubMed Central

Wilson, John X.

2009-01-01

Circulating levels of vitamin C (ascorbate) are low in patients with sepsis. Parenteral administration of ascorbate raises plasma and tissue concentrations of the vitamin and may decrease morbidity. In animal models of sepsis, intravenous ascorbate injection increases survival and protects several microvascular functions, namely, capillary blood flow, microvascular permeability barrier, and arteriolar responsiveness to vasoconstrictors and vasodilators. The effects of parenteral ascorbate on microvascular function are both rapid and persistent. Ascorbate quickly accumulates in microvascular endothelial cells, scavenges reactive oxygen species, and acts through tetrahydrobiopterin to stimulate nitric oxide production by endothelial nitric oxide synthase. A major reason for the long duration of the improvement in microvascular function is that cells retain high levels of ascorbate, which alter redox-sensitive signaling pathways to diminish septic induction of NADPH oxidase and inducible nitric oxide synthase. These observations are consistent with the hypothesis that microvascular function in sepsis may be improved by parenteral administration of ascorbate as an adjuvant therapy. PMID:19319840

The effect of ascorbic acid ingestion on the biochemical and physicochemical risk factors associated with calcium oxalate kidney stone formation.

PubMed

Auer, B L; Auer, D; Rodgers, A L

1998-03-01

The present study was undertaken to determine the effect of ingestion of large doses of vitamin C on urinary oxalate excretion and on a number of other biochemical and physicochemical risk factors associated with calcium oxalate urolithiasis. A further objective was to determine urinary ascorbate excretion and to relate it qualitatively to ingested levels of the vitamin and oxalate excretion. Ten healthy males participated in a protocol in which 4 g ascorbic acid was ingested for 5 days. Urines (24 h) were collected prior to, during and after the protocol. The urine collection procedure was designed to allow for the analysis of oxalate in the presence and absence of an EDTA preservative and for the analysis of ascorbic acid by manual titration using 2,6 dichlorophenolindophenol. Physicochemical risk factors such as the calcium oxalate relative supersaturation and Tiselius risk index were calculated from urine composition. The results showed that erroneously high analytical oxalate levels occur in the asence of preservative. In the preserved samples there was no significant increase in oxalate excretion at any stage of the protocol. Ascorbate excretion increased when vitamin C ingestion commenced but levelled out after 24 hours suggesting that saturation of the metabolic pool is reached within 24 hours after which ingested ascorbic acid is excreted unmetabolized in the urine. While transient statistically significant changes occurred in some of the biochemical risk factors, they were not regarded as being clinically significant. There were no changes in either the calcium oxalate relative supersaturation or Tiselius risk index. It is concluded that ingestion of large doses of ascorbic acid does not affect the principal risk factors associated with calcium oxalate kidney stone formation.

21 CFR 182.8013 - Ascorbic acid.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ascorbic acid. 182.8013 Section 182.8013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8013 Ascorbic acid. (a) Product. Ascorbic acid. (b) Conditions...

21 CFR 582.3013 - Ascorbic acid.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 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 as...

Kinetics of ascorbic acid degradation in un-pasteurized Iranian lemon juice during regular storage conditions.

PubMed

Abbasi, A; Niakousari, M

2008-05-15

The aim of this research was to determine shelf life stability of un-pasteurized lemon juice filled in clear or dark green glass bottles. Presence of light, time and temperature affect the ascorbic acid retention in citrus juices. Bottles were stored at room temperature (27 +/- 3 degrees C) and in the refrigerator (3 +/- 1 degrees C). Total soluble solids, total titrable acidity and pH value were measured every three weeks and analysis was carried out on ascorbic acid content by means of titration method in the presence of 2,6-dichlorophenol indophenol. The study was carried out for 12 weeks after which slight changes in color, taste and apparent texture in some samples were observed and ascorbic acid content reduced by 50%. Soluble solids content, pH value and total acidity were 5.5 degrees Brix, 2.73 and 5 g/100 mL, respectively which appeared not to be significantly influenced by storage time or conditions. Ascorbic acid content initially at 38.50 mg/100 mL was sharply reduced to about 22 mg/100 mL within the first three weeks of storage. The final ascorbic acid content of all samples was about 15 mg/100 mL. The deteriorative reaction of ascorbic acid in the juice at all conditions followed a first-order kinetic model with activation energy of 137 cal mol(-1).

The Effect of Ascorbic Acid and Garlic Administration on Lead-Induced Neural Damage in Rat Offspring's Hippocampus.

PubMed

Sadeghi, Akram; Ebrahimzadeh Bideskan, Alireza; Alipour, Fatemeh; Fazel, Alireza; Haghir, Hossein

2013-02-01

The aim of this study was to investigate ascorbic acid and garlic protective effects on lead-induced neurotoxicity during rat hippocampus development. 90 pregnant wistar rats were divided randomly into nine groups: 1- Animals received leaded water (L). 2- Rats received leaded water and ascorbic acid (L+AA). 3- Animals received leaded water and garlic juice (L+G). 4-Animals received leaded water, ascorbic acid and garlic juice (L+G+AA). 5- Rats treated with ascorbic acid (AA). 6- Rats treated with garlic juice (G). 7- Rats treated with ascorbic acid and garlic juice (AA+G). 8- Rats treated with tap water plus 0.4 ml/l normal hydrogen chloride (HCl) and 0.5 mg/l Glucose (Sham). 9- Normal group (N). Leaded water (1500 ppm), garlic juice (1 ml/100g/day, gavage) and ascorbic acid (500 mg/kg/day, IP) were used. Finally, blood lead levels (BLL) were measured in both rats and their offspring. The rat offspring brain sections were stained using Toluidine Blue and photographed. Dark neurons (DNs) were counted to compare all groups. BLL significantly increased in L group compared to control and sham groups and decreased in L+G and L+AA groups in comparison to the L group (P<0.05). the number of DNs in the CA1, CA3, and DG of rat offspring hippocampus significantly increased in L group in comparison to control and sham groups (P<0.05) and decreased in L+G and L+AA groups compared to L group (P<0.05). Garlic juice and ascorbic acid administration during pregnancy and lactation may protect lead-induced neural damage in rat offspring hippocampus.

Enzymatic Production of Ascorbic Acid-2-phosphate by Recombinant Acid Phosphatase.

PubMed

Zheng, Kai; Song, Wei; Sun, Anran; Chen, Xiulai; Liu, Jia; Luo, Qiuling; Wu, Jing

2017-05-24

In this study, an environmentally friendly and efficient enzymatic method for the synthesis of l-ascorbic acid-2-phosphate (AsA-2P) from l-ascorbic acid (AsA) was developed. The Pseudomonas aeruginosa acid phosphatase (PaAPase) was expressed in Escherichia coli BL21. The optimal temperature, optimal pH, K m , k cat , and catalytic efficiency of recombinant PaAPase were 50 °C, 5.0, 93 mM, 4.2 s -1 , and 2.7 mM -1 min -1 , respectively. The maximal dry cell weight and PaAPase phosphorylating activity reached 8.5 g/L and 1127.7 U/L, respectively. The highest AsA-2P concentration (50.0 g/L) and the maximal conversion (39.2%) were obtained by incubating 75 g/L intact cells with 88 g/L AsA and 160 g/L sodium pyrophosphate under optimal conditions (0.1 mM Ca 2+ , pH 4.0, 30 °C) for 10 h; the average AsA-2P production rate was 5.0 g/L/h, and the AsA-2P production system was successfully scaled up to a 7.5 L fermenter. Therefore, the enzymatic process showed great potential for production of AsA-2P in industry.

Liquid chromatographic determination of L-ascorbic acid in candies and soft drinks.

PubMed

Maeda, Y; Ochi, S; Masui, T; Matubara, S

1988-01-01

The L-ascorbic acid (AsA) contents of candies and soft drinks available in the market were determined by liquid chromatography (LC). Samples are cleaned up on a disposable Sep-Pak C18 cartridge followed by reverse phase separation on an ODS column using a mobile phase of 0.1% phosphoric acid (pH 2.2). The AsA peak is detected on the basis of the UV absorption at 254 nm. The detection limit was 1 microgram/mL final concentration. Recoveries of AsA added at levels of 1-10 mg/g candy and 1-10 mg/10 mL soft drink were 99.2-101.7% with a coefficient of variation of 0.52-1.20% (n = 5). The present method allows rapid and accurate assays because it is a simple procedure compared with the official dye-titration method, and it is suitable for the routine analysis of AsA in selected candies and soft drinks.

Vitamin C physiology: the known and the unknown and Goldilocks

PubMed Central

Padayatty, Sebastian J; Levine, Mark

2016-01-01

Vitamin C (Ascorbic Acid), the antiscorbutic vitamin, cannot be synthesized by humans and other primates, and has to be obtained from diet. Ascorbic acid is an electron donor and acts as a cofactor for fifteen mammalian enzymes. Two sodium-dependent transporters are specific for ascorbic acid, and its oxidation product dehydroascorbic acid is transported by glucose transporters. Ascorbic acid is differentially accumulated by most tissues and body fluids. Plasma and tissue vitamin C concentrations are dependent on amount consumed, bioavailability, renal excretion, and utilization. To be biologically meaningful or to be clinically relevant, in vitro and in vivo studies of vitamin C actions have to take into account physiologic concentrations of the vitamin. In this paper, we review vitamin C physiology; the many phenomena involving vitamin C where new knowledge has accrued or where understanding remains limited; raise questions about the vitamin that remain to be answered; and explore lines of investigations that are likely to be fruitful. PMID:26808119

The use of cyclic voltammetry to study the oxidation of l-5-methyltetrahydrofolate and its preservation by ascorbic acid.

PubMed

Rozoy, Elodie; Simard, Stephan; Liu, Yazheng; Kitts, David; Lessard, Jean; Bazinet, Laurent

2012-06-01

A cyclic voltammetry study of 1mM l-5-methyltetrahydrofolate (l-5-MTHF) was performed in pH 5.5 Britton-Robinson buffer at room temperature to study the stability of l-5-MTHF alone and in combination with ascorbic acid (AA). The degradation of l-5-MTHF and AA over a period of 12h both followed first order reaction kinetics. Using this technique, oxidation peaks of l-5-MTHF were identified at +0.17 and +1.18V, and another oxidation peak appeared after 4h under air at +0.89V. Cyclic voltammetry and HPLC quantification enable us to confirm that l-5-MTHF can be highly preserved by the addition of an equimolar concentration of AA. This treatment was equivalent to a purge of nitrogen used to remove oxygen and thus minimise oxidation of l-5-MTHF when present in aqueous solutions. HPLC confirmed the fact that a full regeneration of oxidised l-5-MTHF occurred with the addition of sodium ascorbate, thus denoting that the redox character of l-5-MTHF can be controlled by the presence of reducing agents. Cyclic voltammetry proved to be a sensitive and accurate method for characterising l-5-MTHF oxidation and potential preservation with ascorbic acid. To our knowledge, this is the first study that has demonstrated the number of oxidation sites on l-5-MTHF. Copyright © 2011 Elsevier Ltd. All rights reserved.

Ascorbic acid induces alkaline phosphatase, type X collagen, and calcium deposition in cultured chick chondrocytes.

PubMed

Leboy, P S; Vaias, L; Uschmann, B; Golub, E; Adams, S L; Pacifici, M

1989-10-15

During the process of endochondral bone formation, proliferating chondrocytes give rise to hypertrophic chondrocytes, which then deposit a mineralized matrix to form calcified cartilage. Chondrocyte hypertrophy and matrix mineralization are associated with expression of type X collagen and the induction of high levels of the bone/liver/kidney isozyme of alkaline phosphatase. To determine what role vitamin C plays in these processes, chondrocytes derived from the cephalic portion of 14-day chick embryo sternae were grown in the absence or presence of exogenous ascorbic acid. Control untreated cells displayed low levels of type X collagen and alkaline phosphatase activity throughout the culture period. However, cells grown in the presence of ascorbic acid produced increasing levels of alkaline phosphatase activity and type X collagen mRNA and protein. Both alkaline phosphatase activity and type X collagen mRNA levels began to increase within 24 h of ascorbate treatment; by 9 days, the levels of both alkaline phosphatase activity and type X collagen mRNA were 15-20-fold higher than in non-ascorbate-treated cells. Ascorbate treatment also increased calcium deposition in the cell layer and decreased the levels of types II and IX collagen mRNAs; these effects lagged significantly behind the elevation of alkaline phosphatase and type X collagen. Addition of beta-glycerophosphate to the medium increased calcium deposition in the presence of ascorbate but had no effect on levels of collagen mRNAs or alkaline phosphatase. The results suggest that vitamin C may play an important role in endochondral bone formation by modulating gene expression in hypertrophic chondrocytes.

[Cholesterol metabolism and lipid peroxidation processes in hypodynamia. Effect of using ascorbic acid and alpha-tocopherol].

PubMed

Elikov, A V; Tsapok, P I

2010-01-01

Study status of cholesterol metabolism, processes of lipid peroxidation and antioxidant protection in blood plasma, erythrocytes and homogenates of the, heart, liver, muscle femors of rats attached to movement active. Establishment effects application of ascorbic acid and alpha-tocopherol. Ascorbic acid and alpha-tocopherol were infused daily. The daily dosage was 2 and 1 mg respectively. Characteristic shift changes of cholesterol metabolism in conditions of limited muscular activity were revealed. It was shown that vitamin antioxidants play a role in correction of metabolic disorders in case of immobile distress syndrome.

Further investigations on the role of ascorbic acid in stratum corneum lipid models after UV exposure.

PubMed

Trommer, Hagen; Böttcher, Rolf; Huschka, Christoph; Wohlrab, Wolfgang; Neubert, Reinhard H H

2005-08-01

This study is the continuation of our research into vitamin C and its possible effects on human skin after topical administration. The effects of ascorbic acid, iron ions and UV irradiation on stratum corneum lipid models were investigated. The lipid models used were: a simple system (linolenic acid dispersion), a complex system (liposomes consisting of dipalmitoylphosphatidylcholine, cholesterol and linolenic acid) and complex systems with additionally incorporated ceramides (types III and IV). The lipid peroxidation was quantified by the thiobarbituric acid assay. A human adult low-calcium high-temperature (HaCaT) keratinocytes cell culture was used as a second in-vitro model. The amount of intracellular peroxides was determined by measuring the fluorescence intensity using the dihydrorhodamine 123 assay. Electron paramagnetic resonance spectroscopy was used to study the influence of ascorbic acid and iron ions on the signal intensity of 5-doxylstearic acid during UV exposure. Ascorbic acid showed prooxidative properties in the thiobarbituric acid assay whereas cell protection was measured in the HaCaT keratinocytes experiments. Electron paramagnetic resonance investigations revealed different extents of free radical production generated by iron ions, ascorbic acid and UV irradiation. In evaluating the results from this study new aspects of the mechanism of lipid damage caused by these three factors were suggested, transcending the simple redox behaviour of ascorbic acid.

Effect of ascorbate and dehydroascorbate on tissue uptake of glucose.

PubMed

Mooradian, A D

1987-09-01

In vitro studies have suggested that ascorbate or dehydroascorbate share with glucose the same tissue-transport carrier. To determine if ascorbic acid or its oxidized form can inhibit tissue uptake of glucose, the brain uptake index (BUI) and muscle uptake index of glucose were determined by single arterial injection tissue-sampling technique. The injectate was either buffered Ringer's solution with varying concentrations of ascorbate, dehydroascorbate (pH 7.4), or 70% serum from individuals on vitamin C supplements. Ascorbic acid over a wide range of concentrations (0-10,000 mg/L) did not reduce the BUI. Ascorbic acid reduced BUI from the control value of 33 +/- 3.2 to 20.1 +/- 2.2% (P less than .01) only at 100,000 mg/L; this effect was probably secondary to osmotic disruption of blood-brain barrier. In contrast, dehydroascorbate inhibited the BUI of glucose from baseline value of 32.8 +/- 1.1 to 10.7 +/- 0.67%, with an estimated Ki of 13.0 mM. Masseter muscle glucose uptake was not significantly altered over a wide range of ascorbate or dehydroascorbate concentrations in the injectate. Dehydroascorbate (7500 mg/L) did not significantly reduce the BUI of [14C]phenylalanine (55.2 +/- 4.4 vs. 62.1 +/- 4.2% in controls). When serum from six individuals on calcium ascorbate (3-5 g/day) was compared with that of nine controls, the BUI was not different (19.3 +/- 1.7 vs. 19.3 +/- 1.1%). Similarly, supplementing the diet of eight healthy volunteers with 1 g calcium ascorbate for 8 days did not alter the BUI of glucose.(ABSTRACT TRUNCATED AT 250 WORDS)

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

PubMed

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. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development and characterization of a FIA system for selective assay of L-ascorbic acid in food samples.

PubMed

Vig, Attila; Igloi, Attila; Adanyi, Nora; Gyemant, Gyongyi; Csutoras, Csaba; Kiss, Attila

2010-10-01

An amperometric detector and an enzymatic reaction were combined for the measurement of L-ascorbic acid. The enzyme cell (containing immobilized ascorbate oxidase) was connected to a flow injection analyzer (FIA) system with a glassy carbon electrode as an amperometric detector. During optimization and measurements two sample injectors were used, one before and one after the enzyme cell, thus eliminating the background interferences. Subtraction of the signal area given in the presence of enzyme from the one given in the absence of enzyme was applied for measuring analyte concentrations and calibration at 400 mV. Analysis capacity of system is 25 samples/hour. The relative standard deviation (RSD) was below 5% (5 times repeated, 400 μmol/L conc.), linearity up to 400 μmol/L, limit of detection (LOD) 5 μmol/L, fitting of calibration curve in 25-400 μmol/L range was R (2) = 0.99.

Effect of platelets on apparent leucocyte ascorbic acid content.

PubMed

Evans, R M; Currie, L; Campbell, A

1980-09-01

The leucocyte ascorbic acid content is widely used as a measure of tissue ascorbic acid status. Standard methods of analysis, however, isolate both leucocytes and platelets (buffy layer), with consequent overestimation, since platelet ascorbic acid is attributed to the leucocytes. Fourteen healthy individuals on ascorbic acid supplements and 11 patients on mega dose ascorbic acid therapy were studied. A significant correlation was demonstrated between the 'leucocyte' ascorbic acid content and the platelet: leucocyte ratio (r = 0.70, P < 0.001). It is suggested that changes in the relative distribution of platelets and leucocytes in the blood will result in an apparent change in the 'leucocyte' ascorbic acid content regardless of any actual change in the ascorbic acid content of the cells.

Ascorbic acid metabolism during bilberry (Vaccinium myrtillus L.) fruit development.

PubMed

Cocetta, Giacomo; Karppinen, Katja; Suokas, Marko; Hohtola, Anja; Häggman, Hely; Spinardi, Anna; Mignani, Ilaria; Jaakola, Laura

2012-07-15

Bilberry (Vaccinium myrtillus L.) possesses a high antioxidant capacity in berries due to the presence of anthocyanins and ascorbic acid (AsA). Accumulation of AsA and the expression of the genes encoding the enzymes of the main AsA biosynthetic route and of the ascorbate-glutathione cycle, as well as the activities of the enzymes involved in AsA oxidation and recycling were investigated for the first time during the development and ripening of bilberry fruit. The results showed that the AsA level remained relatively stable during fruit maturation. The expression of the genes encoding the key enzymes in the AsA main biosynthetic route showed consistent trends with each other as well as with AsA levels, especially during the first stages of fruit ripening. The expression of genes and activities of the enzyme involved in the AsA oxidation and recycling route showed more prominent developmental stage-dependent changes during the ripening process. Different patterns of activity were found among the studied enzymes and the results were, for some enzymes, in accordance with AsA levels. In fully ripe berries, both AsA content and gene expression were significantly higher in skin than in pulp. Copyright © 2012 Elsevier GmbH. All rights reserved.

Vitamin C. Biosynthesis, recycling and degradation in mammals.

PubMed

Linster, Carole L; Van Schaftingen, Emile

2007-01-01

Vitamin C, a reducing agent and antioxidant, is a cofactor in reactions catalyzed by Cu(+)-dependent monooxygenases and Fe(2+)-dependent dioxygenases. It is synthesized, in vertebrates having this capacity, from d-glucuronate. The latter is formed through direct hydrolysis of uridine diphosphate (UDP)-glucuronate by enzyme(s) bound to the endoplasmic reticulum membrane, sharing many properties with, and most likely identical to, UDP-glucuronosyltransferases. Non-glucuronidable xenobiotics (aminopyrine, metyrapone, chloretone and others) stimulate the enzymatic hydrolysis of UDP-glucuronate, accounting for their effect to increase vitamin C formation in vivo. Glucuronate is converted to l-gulonate by aldehyde reductase, an enzyme of the aldo-keto reductase superfamily. l-Gulonate is converted to l-gulonolactone by a lactonase identified as SMP30 or regucalcin, whose absence in mice leads to vitamin C deficiency. The last step in the pathway of vitamin C synthesis is the oxidation of l-gulonolactone to l-ascorbic acid by l-gulonolactone oxidase, an enzyme associated with the endoplasmic reticulum membrane and deficient in man, guinea pig and other species due to mutations in its gene. Another fate of glucuronate is its conversion to d-xylulose in a five-step pathway, the pentose pathway, involving identified oxidoreductases and an unknown decarboxylase. Semidehydroascorbate, a major oxidation product of vitamin C, is reconverted to ascorbate in the cytosol by cytochrome b(5) reductase and thioredoxin reductase in reactions involving NADH and NADPH, respectively. Transmembrane electron transfer systems using ascorbate or NADH as electron donors serve to reduce semidehydroascorbate present in neuroendocrine secretory vesicles and in the extracellular medium. Dehydroascorbate, the fully oxidized form of vitamin C, is reduced spontaneously by glutathione, as well as enzymatically in reactions using glutathione or NADPH. The degradation of vitamin C in mammals is

Synthesis, characterization, thermal and antimicrobial studies of diabetic drug models: Complexes of vanadyl(II) sulfate with ascorbic acid (vitamin C), riboflavin (vitamin B2) and nicotinamide (vitamin B3)

NASA Astrophysics Data System (ADS)

Refat, Moamen S.

2010-04-01

The oxovanadium(II) complexes of the different vitamins like ascorbic acid (vitamin C; Vit. C), riboflavin (vitamin B2; Vit. B2) and nicotinamide (vitamin B3; Vit. B3) were synthesized and characterized by elemental analysis, molar conductance, IR, electronic, magnetic measurements, thermal studies, XRD and SEM. Conductance measurements indicated that the vanadyl(II) complexes of Vit. B2 and Vit. B3 are 1:2 electrolytes except for [VO(Vit. C) 2(H 2O) 2] complex is non-electrolyte. IR data show that Vit. B2 is bidentate ligand against azomethine nitrogen of pyrazine ring and C dbnd O of pyrimidine-2,4-dione but Vit. B3 and Vit. C acts as a monodentate ligand through pyridine nitrogen and hydroxo oxygen of furan ring, respectively. Electronic spectral measurements indicated that all VO(II) complexes have a square-pyramidal geometry. Magnetic measurements for the new vanadyl(II) complexes are in a good agreement with the proposed formula. Thermal analyses (TG/DSC) of the studied complexes show that the decomposition process takes place in more than two steps. XRD refer that VO(II) complexes have an amorphous behavior. The surface morphology of the complexes was studied by SEM. The antimicrobial activities of the ligands and its complexes indicate that the vanadyl(II) complexes possess high antibacterial and antifungal activities towards the bacterial species and the fungal species than start ligands.

[The effects of the combined use of mineral water with ascorbic acid and rutin experimentally and clinically].

PubMed

Polushina, N D; Kartazaeva, V A; Botvineva, L A; Kozhevnikov, S A

2000-01-01

Effects of a single and course intake of glucose, ascorbic acid and rutin in combination with mineral water Essentuki N17 on blood levels of glucose, hydrocortisone, ACTH, insulin were studied in 336 Wistar male rats. 80 patients with diabetes mellitus type I and II received a course of ascorutin and mineral water. Mineral water proved able to reduce a hyperglycemic effect of vitamins. A course of mineral water and ascorutin promotes improvement of carbohydrate, lipid metabolism, elevates plasma content of ascorbic acid, diminishes the need in sugar-reducing drugs.

Synthesis of colloidal silver nanoparticle clusters and their application in ascorbic acid detection by SERS.

PubMed

Cholula-Díaz, Jorge L; Lomelí-Marroquín, Diana; Pramanick, Bidhan; Nieto-Argüello, Alfonso; Cantú-Castillo, Luis A; Hwang, Hyundoo

2018-03-01

Ascorbic acid (vitamin C) has an essential role in the human body mainly due to its antioxidant function. In this work, metallic silver nanoparticle (AgNP) colloids were used in SERS experiments to detect ascorbic acid in aqueous solution. The AgNPs were synthesized by a green method using potato starch as reducing and stabilizing agent, and water as the solvent. The optical properties of the yellowish as-synthesized silver colloids were characterized by UV-vis spectroscopy, in which besides a typical band at 410 nm related to the localized surface plasmon resonance of the silver nanoparticles, a shoulder band around 500 nm, due to silver nanoparticle cluster formation, is presented when relatively higher concentrations of starch are used in the synthesis. These starch-capped silver nanoparticles show an intrinsic Raman peak at 1386 cm -1 assigned to deformation modes of the starch structure. The increase of the intensity of the SERS peak at 1386 cm -1 with an increase in the concentration of the ascorbic acid is related to a decrease of the gap between dimers and trimers of the silver nanoparticle clusters produced by the presence of ascorbic acid in the colloid. The limit of detection of this technique for ascorbic acid is 0.02 mM with a measurement concentration range of 0.02-10 mM, which is relevant for the application of this method for detecting ascorbic acid in biological specimen. Copyright © 2017 Elsevier B.V. All rights reserved.

Ascorbic acid and melatonin reduce heat-induced performance inhibition and oxidative stress in Japanese quails.

PubMed

Sahin, N; Onderci, M; Sahin, K; Gursu, M F; Smith, M O

2004-02-01

1. The effects of ascorbic acid (L-ascorbic acid) and melatonin supplementation on performance, carcase characteristics, malondialdehyde (MDA) as lipid peroxidation indicator, ascorbic acid, retinol, tocopherol and mineral status in the Japanese quail (Coturnix coturnix japonica) exposed to high ambient temperature were evaluated. 2. Two hundred and forty Japanese quails (10 d old) were randomly assigned to 8 treatment groups consisting of 10 replicates of three birds each. The birds were kept in a temperature-controlled room at 22 degrees C (Thermoneutral, TN groups) or 34 degrees C (for 8 h/d; 09:00 to 17:00 h; Heat stress, HS groups). Birds in both TN and HS were fed either a basal (control) diet or the basal diet supplemented with 250 mg of L-ascorbic acid/kg of diet (Ascorbic acid group), 40 mg of melatonin/kg of diet (Melatonin group) or both (Ascorbic acid + Melatonin group). 3. Supplementing heat-stressed quails with ascorbic acid and melatonin improved performance compared with the control group. Effects generally were greatest in quails supplemented with both ascorbic acid and melatonin. 4. Although supplementation did not consistently restore the concentrations of serum ascorbic acid, retinol and tocopherol to those of TN groups, these concentrations increased significantly with supplementation. Furthermore, serum and liver MDA and serum cholesterol and glucose concentrations were lower in the supplemented groups than in the heat-stressed controls. 5. Within each environment, excretion of Ca, P, Mg, Zn, Fe and Cr were lowest in the combination group and, in all cases, highest in the HS group. Interactions between diet and temperature were detected for live weight gain, cold carcase weight, MDA, ascorbic acid, tocopherol concentrations and excretion of zinc. 6. The results of the study indicate that ascorbic acid and melatonin supplementation attenuate the decline in performance and antioxidant and mineral status caused by heat stress and such

[Ion chromatography of L-ascorbic acid, sulfite and thiosulfate using their postcolumn reactions with cerium (IV) and fluorescence detection of cerium (III)].

PubMed

Chen, Q; Hu, K; Miura, Y

1999-09-01

An ion chromatographic method was used to separate the species of L-ascorbic acid, sulfite and thiosulfate in their mixtures. This method is based on the separation of each anion in their mixtures by using a separation column, and then on the fluorimetric measurement of cerium (III) formed by a postcolumn reaction of cerium (IV) with the species of L-ascorbic acid, sulfite and thiosulfate in the effluent. The optimal conditions for separating and determining the above three species have been established. By using a 3 mmol/L carbonate eluent, the species of L-ascorbic acid, sulfite and thiosulfate could be eluted at the proper retention times of 1.7, 2.6 and 5.0 min, respectively, and these three anions could be separated completely. The effects of the concentrations of cerium (IV) and sulfuric acid in the postcolumn reaction solution on the chromatographic peak-height were tested in order to obtain the optimal peak-height. It was found that the peak-height at first increases rapidly with an increase in the concentration of cerium (IV) and sulfuric acid respectively up to a certain concertation, then increases slowly. These critical concentrations of cerium (IV) and sulfuric acid also depend on the amount of the analyte injected. Meanwhile the baseline signals of the sepectra increase with an increase in the concentration of cerium (IV). Some concentrations above the critical concentration of sulfuric acid could be selected as the optimal concentration of sulfuric acid, but the concentration of cerium (IV) should be optimized by establishing a compromise between the higher peak-height and the lower baseline signal. The detection limit of this method was found to be 1 mumol/L for thiosulfate when an amount of 100 microL analyte was injected.

Degradation of histamine in the presence of ascorbic acid and Cu2+ ion; involvement of hydrogen peroxide.

PubMed

Yamamoto, I; Ohmori, H

1981-01-01

In the presence, but not in the absence of Cu2+, ascorbate decomposes histamine in citrate phosphate buffer (pH 6.5) at 37 degrees, but not at 0 degrees. The breakdown is completely inhibited by catalase, but only slightly by superoxide dismutase, and scavengers of OH. like benzoic acid, ethanol or potassium iodide. A1 O2 scavenger, alpha-tocopherol also did not show significant effects on the reaction. On the other hand, addition of H2O2 to the reaction mixture markedly enhances the rate of histamine breakdown induced by ascorbate or ascorbate-Cu2+ systems. However, H2O2 alone cannot breakdown histamine even in the presence of Cu2+. Histamine breakdown induced by ascorbate appears to be dependent upon the autooxidation of this vitamin. From these results and the findings reported by Chatterjee et al. that the products of its aerobic oxidation, dehydroascorbic acid and H2O2 were ineffective in reacting with histamine in the presence of Cu2+, it is concluded that the combination of H2O2 and the intermediate of ascorbate oxidation (monodehydroascorbic acid or other unstable species), both of which are produced during the autooxidation of ascorbate, plays a major role in the histamine transformation by ascorbate-Cu2+ system.

Ab initio study of the structural properties of ascorbic acid (vitamin C)

NASA Astrophysics Data System (ADS)

Allen, Reeshemah N.; Shukla, M. K.; Reed, Demarcio; Leszczynski, Jerzy

Geometries of the neutral and ionic tautomeric species of ascorbic acid were optimized at the density functional theory (DFT) level using the B3LYP functional. The radical species were evaluated using the unrestricted B3LYP method. Single-point energy calculations were also performed using the Møller-Plesset (MP2) and unrestricted MP2 (UMP2) methods for the closed-shell and open-shell systems, respectively. The effects of aqueous solution were evaluated using the conducting polarized continuum model (CPCM) and polarized continuum model (PCM). The geometries of most stable radicals in the respective groups were also optimized in the water solution using the CPCM model at the UB3LYP level. All calculation were performed using the 6-311++G(d,p) basis set. The nature of stationary points on the gas phase potential energy surfaces (PESs) was evaluated using vibrational frequency calculations; all geometries characterize local minima. The species obtained by the deprotonation of the O3 site is the most stable monoanion of ascorbic acid. For the radical species, the structure obtained by the dehydrogenation of the O3 site is the most stable monoradical. Among the radical anions, the species obtained by the deprotonation of the O3 site and subsequent dehydrogenation of the O2 site is the most stable in the gas phase and in an aqueous medium. The computed isotropic hyperfine coupling constants of this species were found to be in good agreement with the experimental data. Our investigation also supports the earlier findings that the oxidized species of ascorbic acid in water solution by the OH? radical is radical anion of the AAO?3O-2 form. The spin densities and molecular electrostatic potentials are also discussed.

Vitamin C metabolites, independent of smoking status, significantly enhance leukocyte, but not plasma ascorbate concentrations.

PubMed

Moyad, Mark A; Combs, Maile A; Vrablic, Angelica S; Velasquez, Janet; Turner, Benilda; Bernal, Samuel

2008-10-01

The objective of this study was to test the effects of acute doses of vitamin C alone, calcium ascorbate with vitamin C metabolites, and placebo, on total plasma and leukocyte vitamin C concentrations over 24 hours. A double-blind, placebo-controlled, four-way crossover study was performed consisting of four separate phases lasting 24 hours each and utilizing one of four oral 1000-mg preparations within each phase (one of vitamin C alone, two separate vitamin C formulations of calcium ascorbate with vitamin C metabolites, and placebo). There was a 7-day washout between phases, and blood draws at seven time points within each phase of the study for a total of 28 serologic measurements per subject and 420 total measurements for the entire clinical trial. Vitamin C concentration in plasma and leukocytes were measured by high-performance liquid chromatography at baseline and at six sequential time periods over 24 hours. Fifteen healthy males were enrolled, aged 18-39 years; nine were had never smoked and six were chronic smokers. No significant difference in plasma vitamin C levels was observed when comparing the different preparations. However, at 24 hours, calcium ascorbate with metabolites resulted in significantly higher concentrations of vitamin C in leukocytes (P<0.0001) compared with vitamin C alone. These results were similar for both metabolite formulations, and independent of smoking status. Regardless of smoking status, vitamin C metabolites may enhance leukocyte utilization of vitamin C itself, despite no consistent difference in plasma levels among the different preparations. A larger clinical investigation is warranted to confirm these preliminary findings, and to determine the clinical relevance of this impact on overall immune function.

21 CFR 182.3013 - Ascorbic acid.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ascorbic acid. 182.3013 Section 182.3013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... acid. (a) Product. Ascorbic acid. (b) Conditions of use. This substance is generally recognized as safe...

Ascorbic acid insufficiency induces the severe defect on bone formation via the down-regulation of osteocalcin production

PubMed Central

Kim, Won; Bae, Seyeon; Kim, Hyemin; Kim, Yejin; Choi, Jiwon; Lim, Sun Young; Lee, Hei Jin; Lee, Jihyuk; Choi, Jiyea; Jang, Mirim; Lee, Kyoung Eun; Chung, Sun G.; Hwang, Young-il

2013-01-01

The L-gulono-γ-lactone oxidase gene (Gulo) encodes an essential enzyme in the synthesis of ascorbic acid from glucose. On the basis of previous findings of bone abnormalities in Gulo-/- mice under conditions of ascorbic acid insufficiency, we investigated the effect of ascorbic acid insufficiency on factors related to bone metabolism in Gulo-/- mice. Four groups of mice were raised for 4 weeks under differing conditions of ascorbic acid insufficiency, namely, wild type; ascorbic acid-sufficient Gulo-/- mice, 3-week ascorbic acid-insufficient Gulo-/- mice, and 4-week ascorbic acid-insufficient Gulo-/- mice. Four weeks of ascorbic acid insufficiency resulted in significant weight loss in Gulo-/- mice. Interestingly, average plasma osteocalcin levels were significantly decreased in Gulo-/- mice after 3 weeks of ascorbic acid insufficiency. In addition, the tibia weight in ascorbic acid-sufficient Gulo-/- mice was significantly higher than that in the other three groups. Moreover, significant decreases in trabecular bone volume near to the growth plate, as well as in trabecular bone attachment to the growth plate, were evident in 3- or 4-week ascorbic acid-insufficient Gulo-/-. In summary, ascorbic acid insufficiency in Gulo-/- mice results in severe defects in normal bone formation, which are closely related to a decrease in plasma osteocalcin levels. PMID:24386598

Supplemental vitamin C appears to slow racing greyhounds.

PubMed

Marshall, Rebecca J; Scott, Karen C; Hill, Richard C; Lewis, Daniel D; Sundstrom, Deborah; Jones, Galin L; Harper, Jean

2002-06-01

During strenuous exercise, markers of oxidation increase and antioxidant capacity decreases. Antioxidants such as vitamin C may combat this oxidation stress. The benefits of vitamin C to greyhounds undertaking intense sprint exercise has not been investigated. The objective of this experiment was to determine whether a large dose (1 g or 57 mmol) of ascorbic acid influences performance and oxidative stress in greyhounds. Five adult female, trained racing greyhounds were assigned to receive each of three treatments for 4 wk per treatment: 1) no supplemental ascorbate; 2) 1 g oral ascorbate daily, administered after racing; 3) 1 g oral ascorbate daily, administered 1 h before racing. Dogs raced 500 m twice weekly. At the end of each treatment period, blood was collected before and 5 min, 60 min and 24 h after racing. Plasma ascorbate, alpha-tocopherol, thiobarbituric acid-reducing substances (TBARS) and Trolox equivalent antioxidant capacity (TEAC) concentrations were measured and adjusted to compensate for hemoconcentration after racing. TBARS, TEAC and alpha-tocopherol concentrations were unaffected by supplemental vitamin C. Plasma ascorbic acid concentrations 60 min after racing were higher in dogs that received vitamin C before racing than in dogs that either received no vitamin C or received vitamin C after racing. The dogs ran, on average, 0.2 s slower when supplemented with 1 g of vitamin C, equivalent to a lead of 3 m at the finish of a 500-m race. Supplementation with vitamin C, therefore, appeared to slow racing greyhounds.

Interchange reaction of disulfides and denaturation of oxytocin by copper(II)/ascorbic acid/O2 system.

PubMed

Inoue, H; Hirobe, M

1987-05-29

The interchange reaction of disulfides was caused by the copper(II)/ascorbic acid/O2 system. The incubation of two symmetric disulfides, L-cystinyl-bis-L-phenylalanine (PP) and L-cystinyl-bis-L-tyrosine (TT), with L-ascorbic acid and CuSO4 in potassium phosphate buffer (pH 7.2, 50 mM) resulted in the formation of an asymmetric disulfide, L-cystinyl-L-phenylalanine-L-tyrosine (PT), and the final ratio of PP:PT:TT was 1:2:1. As the reaction was inhibited by catalase and DMSO only at the initial time, hydroxyl radical generated by the copper(II)/ascorbic acid/O2 system seemed to be responsible for the initiation of the reaction. Oxytocin and insulin were denatured by this system, and catalase and DMSO similarly inhibited these denaturations. As the composition of amino acids was unchanged after the reaction, hydroxyl radical was thought to cause the cleavage and/or interchange reaction of disulfides to denature the peptides.

Safety and tolerance of ester-C compared with regular ascorbic acid.

PubMed

Gruenwald, Joerg; Graubaum, Hans-Joachim; Busch, Regina; Bentley, Christine

2006-01-01

The goal of this randomized, double-blind crossover clinical trial in 50 healthy volunteers sensitive to acidic foods was to evaluate whether Ester-C calcium ascorbate causes fewer epigastric adverse effects than are produced by regular ascorbic acid (AA). Volunteers were randomly separated into 2 groups of 25. The study comprised an observation period of 9 days (phase 1 medication for 3 consecutive days, washout phase for 3 consecutive days, phase 2 medication for 3 consecutive days). Participants took 1000 mg vitamin C as Ester-C during phase 1 of the study followed by 1000 mg of vitamin C as AA during phase 2, or vice versa. During the course of the study, 3 examinations for the evaluation of epigastric adverse effects were performed (on days 0, 3, and 9). Participants used a diary to record epigastric adverse effects on a daily basis. In total, 28 (56%) of 50 participants reported 88 epigastric adverse effects of mild to moderate intensity. Of these 88 adverse effects, 33 (37.5%) occurred after intake of Ester-C and 55 (62.5%) were noted after intake of AA. The tolerability of Ester-C was rated "very good" by 72% of participants, whereas AA was rated "very good" by only 54%. This difference is statistically significant (P<.05). Investigators concluded that Ester-C compared with AA caused significantly fewer epigastric adverse effects in participants sensitive to acidic foods and that Ester-C is much better tolerated.

21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Nicotinamide-ascorbic acid complex. 172.315... 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 conditions...

Lutein, Trolox, ascorbic acid and combination of Trolox with ascorbic acid can improve boar semen quality during cryopreservation.

PubMed

Varo-Ghiuru, Florin; Miclea, Ileana; Hettig, Andrea; Ladoşi, Ioan; Miclea, Vasile; Egerszegi, István; Zăhan, Marius

2015-01-01

Due to pour quality of cryopreserved boar semen, artificial innsemination with frozen-thawed semen is quite limited. Developing protocols of boar semen cryopreservation represents a priority but also a challange. The goal of the present study was to evaluate the antioxidant potential of lutein, Trolox, ascorbic acid, and certain combinations of Trolox with ascorbic acid on boar semen cryopreservation procedure. Antioxidants were added to lactose-egg yolk extender, containing a final concentration of 3% glycerol and 0.5% Equex-STM. Semen of six boars was cryopreserved using straw-freezing procedure. After cryopreservation semen was thawed and evaluated for motility, normal apical ridge (NAR), hypo-osmotic swelling test (HOST) and DNA fragmentation index (DFI). Data were analyzed by one-way ANOVA. The results showed better motility after thawing at the concentration of 10 μM lutein, 200 μM Trolox, 200 μM ascorbic acid and 400-200 μM Trolox and ascorbic acid. The supplementation on boar freezing extender with 10 μM lutein increased post-thawed motility, NAR and HOST values (P < 0.01), and decrease DFI (P < 0.05) in comparison with control group. Similar results were obtained using 400-200 μM Trolox and ascorbic acid, with better results in the case of DFI (P < 0.01). In comparison with the control group, a concentration of 200 μM Trolox and 200 μM ascorbic acid provided significant differences (P < 0.01) of motility and NAR. The analysis of sperm characteristics showed that lutein and the mix between Trolox and ascorbic acid used in boar semen cryopreservation can improve the quality of spermatozoa.

Total phenolics, carotenoids, ascorbic acid, and antioxidant properties of fresh-cut mango (Mangifera indica L., cv. Tommy Atkin) as affected by infrared heat treatment.

PubMed

Sogi, D S; Siddiq, M; Roidoung, S; Dolan, K D

2012-11-01

Mango (Mangifera indica L.) is a major tropical fruit that has not been exploited for fresh-cut or minimally processed products on a scale similar to apples, pineapples, or melons. The objective of this study was to investigate the effect of infrared (IR) treatment on total phenolics, carotenoids, ascorbic acid, and antioxidant properties of fresh-cut cubes from 'Tommy Atkin' mangoes. Mango cubes were IR treated (5, 10, 15 min) and evaluated at 4-d intervals during 16-d storage at 4 ± 1 °C. Total phenolics, carotenoids, and ascorbic acid content in fresh-cut control mango cubes were 43.33, 1.37, and 15.97 mg/100 g FW, respectively. IR treatments increased total phenolics (59.23 to 71.16 mg/100 g FW) and decreased ascorbic acid (12.14 to 15.38 mg/100 g, FW). Total carotenoids showed a mixed trend (1.13 to 1.66 mg/100 g, FW). The IR treatment showed a significant positive impact on antioxidant properties (μM TE/100 g, FW) of mango cubes, as assayed by ABTS (261.5 compared with 338.0 to 416.4), DPPH (270.5 compared with 289.4 to 360.5), and ORAC (6686 compared with 8450 to 12230). Total phenolics, carotenoids, ascorbic acid, and antioxidant capacity decreased over 16-d storage. However, IR treated samples had consistently higher ABTS, DPPH, and total phenolics during storage. It was demonstrated that IR treatment can be effectively used in improving antioxidant properties of fresh-cut mangoes with minimal effect on the visual appearance. Various methods/treatments are in use for extending the quality of fresh-cut fruits, including mild heat treatment. This study explored the application of infrared (IR) heat for processing fresh-cut mango cubes and evaluated its effect on vitamin C and antioxidant capacity during 16-d storage. This is the first study reporting on the use of IR heat in fresh-cut fruits. IR treatment was shown to be effective in retaining antioxidant properties of fresh-cut mango cubes with minimal effect on the visual appearance. © 2012 Institute

Simultaneous and sensitive determination of ascorbic acid, dopamine, uric acid, and tryptophan with silver nanoparticles-decorated reduced graphene oxide modified electrode.

PubMed

Kaur, Balwinder; Pandiyan, Thangarasu; Satpati, Biswarup; Srivastava, Rajendra

2013-11-01

In this paper, we report the synthesis of silver nanoparticle-decorated reduced graphene oxide composite (AgNPs/rGO) by heating the mixture of graphene oxide and silver nitrate aqueous solution in the presence of sodium hydroxide. This material was characterized by means of X-ray diffraction, UV-vis spectroscopy, and transmission electron microscopy. AgNPs/rGO based electrochemical sensor was fabricated for the simultaneous determination of ascorbic acid, dopamine, uric acid, and tryptophan. Electrochemical studies were carried out by using cyclic voltammetry, linear sweep voltammetry, and chronoamperometry. AgNPs/rGO modified electrode exhibited excellent electrocatalytic activity, stability, sensitivity, and selectivity with well-separated oxidation peaks toward ascorbic acid, dopamine, uric acid, and tryptophan in the simultaneous determination of their quaternary mixture. The analytical performance of this material as a chemical sensor was demonstrated for the determination of ascorbic acid and dopamine in commercial pharmaceutical samples such as vitamin C tablets and dopamine injections, respectively. The applicability of this sensor was also extended in the determination of uric acid in human urine samples. Copyright © 2013 Elsevier B.V. All rights reserved.

A preliminary study of the electro-oxidation of L-ascorbic acid on polycrystalline silver in alkaline solution

NASA Astrophysics Data System (ADS)

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).

2 L PEG plus ascorbic acid versus 4 L PEG plus simethicon for colonoscopy preparation: a randomized single-blind clinical trial.

PubMed

Gentile, Maurizio; De Rosa, Michele; Cestaro, Giovanni; Forestieri, Pietro

2013-06-01

The 2 L polyethylene glycol (PEG) lavage solution has been proved to be similarly safe and effective as 4 L PEG formulations, in spite of the reduced volume. To compare low-volume PEG-based solution combined with ascorbic acid with high-volume PEG-based solution combined with simethicon in terms of efficacy and patient tolerability. This was a single-blind prospective randomized trial. Patients were randomized to receive either 2 L PEG plus ascorbic acid (PEG+Asc) or 4 L PEG plus simethicon (PEG+Sim). The primary endpoint was overall colon cleansing evaluation, assessed by blinded investigators using Aronchick score. Secondary end points included patient compliance and tolerability and adverse events. Sixty patients received PEG+Asc and 60 received PEG+Sim. Overall bowel cleansing score was considered adequate in 81.67% of the PEG+Asc and 80% of the PEG+Sim groups, respectively. Excellent and good ratings were recorded in 11.6% and 38.3% receiving PEG+Asc as compared with 26.6% and 23.3% of patients receiving PEG+Sim. Patient tolerability and safety were similar with both the preparations. According to our data, low-volume PEG+Asc has comparable efficacy, safety, and tolerability as high-volume PEG+Sim; therefore, it can be considered as a good alternative solution for bowel preparation. More improvements are necessary to achieve the target of a perfect preparation.

Adding of ascorbic acid to the culture medium influences the antioxidant status and some biochemical parameters in the hen granulosa cells.

PubMed

Capcarova, M; Kolesarova, A; Kalafova, A; Bulla, J; Sirotkin, A V

2015-07-01

The aim of the present study was to determine the activity of superoxide dismutase (SOD), total antioxidant status (TAS) of the hen granulosa cells, and selected biochemical parameters, including calcium, phosphorus, sodium, potassium, glucose, cholesterol, proteins, in the culture medium of granulosa cells after exposing them to ascorbic acid in vitro conditions. Ovarian granulosa cells of hens were incubated with various doses of ascorbic acid (E1 0.09 mg/ml, E2 0.13 mg/ml, E3 0.17 mg/ml, E4 0.33 mg/ml, E5 0.5 mg/ml). Ascorbic acid did not manifest antioxidant potential and higher doses of ascorbic acid (0.17; 0.33 and 0.5 mg/ml) decreased the activity of SOD in granulosa cells. Vitamin application resulted in a significantly (p<0.05) higher accumulation of Na+ and K+ in culture media of granulosa cells and decreased the concentration of glucose and proteins. These results indicate that ascorbic acid might be involved in the regulation of selected biochemical and physiological processes in ovarian granulosa cells.

New Methods for the Analysis of Water-Soluble Vitamins in Infant Formula and Adult/Pediatric Nutritionals.

PubMed

Martin, Frederic; Giménez, Ester Campos; Konings, Erik

2016-01-01

Water-soluble vitamins (WSVs) are a group of organic compounds which are essential micronutrients. WSVs could be divided between the B complex group and vitamin C (l-ascorbic acid). Within the B complex group, eight vitamins are recognized: vitamins B1 (thiamin), B2 (riboflavin), B3 (niacin or niacinamide), B5 (pantothenic acid), B6 (pyridoxine, pyridoxal, or pyridoxamine), B7 (biotin), B9 (folic acid), and B12 (various cobalamins). This paper reviews the new methods for the analysis of these vitamins, with a focus on infant formula and adult nutritionals.

Formulation with ascorbic acid and sucrose modulates catechin bioavailability from green tea

PubMed Central

Peters, Catrina M.; Green, Rodney J.; Janle, Elsa M.; Ferruzzi, Mario G.

2009-01-01

In order to investigate the impact of common food ingredients on catechin absorption, green tea (GT) extract (50 mg) was formulated plain, with sucrose (GT+S), with ascorbic acid (GT+AA) and with sucrose and ascorbic acid (GT+S+AA). Bioavailability and bioaccessibility were assessed in Sprague Dawley rats and an in vitro digestion/Caco-2 cell model respectively. Absorption of epigallocatechin (EGC) and epigallocatechin gallate (EGCG) was significantly (P<0.05) enhanced in GT+S+AA formulations (AUC0-6h= 3237.0 and 181.8 pmol*h/L plasma respectively) relative to GT control (AUC0-6h = 1304.1 and 61.0 pmol*h/L plasma respectively). In vitro digestive recovery was higher for EGC and epicatechin (EC) (∼51-53%) relative to EGCG and epicatechin gallate (ECG) (< 20%) and was modestly enhanced in GT+S and GT+S+AA formulations. Accumulation of EGC, EGCG and ECG by Caco-2 cells was significantly (P<0.05) higher from GT+S+AA compared to other formulations while retention of catechins was enhanced in presence of ascorbic acid. These data suggest that formulation with sucrose and ascorbic acid may improve catechin bioavailability by enhancing bioaccessibility and intestinal uptake from tea. PMID:20161530

A rapid method for the simultaneous determination of L-ascorbic acid and acetylsalicylic acid in aspirin C effervescent tablet by ultra performance liquid chromatography-tandem mass spectrometry

NASA Astrophysics Data System (ADS)

Wabaidur, Saikh Mohammad; Alothman, Zeid Abdullah; Khan, Mohammad Rizwan

2013-05-01

In present study, a rapid and sensitive method using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the simultaneous determination of L-ascorbic acid and acetylsalicylic acid in aspirin C effervescent tablet. The optimum chromatographic separation was carried out on a reversed phase Waters® Acquity UPLC BEH C18 column (1.7 μm particle size, 100 mm × 2.1 mm ID) with an isocratic elution profile and mobile phase consisting of 0.1% formic acid in water and acetonitrile (75:25, v/v, pH 3.5) at flow rate of 0.5 mL min-1. The influences of mobile phase composition, flow rate and pH on chromatographic resolution were investigated. The total chromatographic analysis time was as short as 2 min with excellent resolution. Detection and quantification of the target compounds were carried out with a triple quadrupole mass spectrometer using negative electrospray ionization (ESI) and multiple reaction monitoring (MRM) modes. The performance of the method was evaluated and very low limits of detection less than 0.09 μg g-1, excellent coefficient correlation (r2 > 0.999) with liner range over a concentration range of 0.1-1.0 μg g-1 for both L-ascorbic acid and acetylsalicylic acid, and good intraday and interday precisions (relative standard deviations (R.S.D.) <3%), were obtained. Comparison of system performance with traditional liquid chromatography-photo diode array detector (HPLC-PDA) was made with respect to analysis time, sensitivity, linearity and precisions. The proposed UPLC-MS/MS method was found to be reproducible and appropriate for quantitative analysis of L-ascorbic acid and acetylsalicylic acid in aspirin C effervescent tablet.

Enhancing ascorbate in fruits and tubers through over-expression of the L-galactose pathway gene GDP-L-galactose phosphorylase.

PubMed

Bulley, Sean; Wright, Michele; Rommens, Caius; Yan, Hua; Rassam, Maysoon; Lin-Wang, Kui; Andre, Christelle; Brewster, Di; Karunairetnam, Sakuntala; Allan, Andrew C; Laing, William A

2012-05-01

Ascorbate, or vitamin C, is obtained by humans mostly from plant sources. Various approaches have been made to increase ascorbate in plants by transgenic means. Most of these attempts have involved leaf material from model plants, with little success reported using genes from the generally accepted l-galactose pathway of ascorbate biosynthesis. We focused on increasing ascorbate in commercially significant edible plant organs using a gene, GDP-l-galactose phosphorylase (GGP or VTC2), that we had previously shown to increase ascorbate concentration in tobacco and Arabidopsis thaliana. The coding sequence of Actinidia chinensis GGP, under the control of the 35S promoter, was expressed in tomato and strawberry. Potato was transformed with potato or Arabidopsis GGP genes under the control of the 35S promoter or a polyubiquitin promoter (potato only). Five lines of tomato, up to nine lines of potato, and eight lines of strawberry were regenerated for each construct. Three lines of tomato had a threefold to sixfold increase in fruit ascorbate, and all lines of strawberry showed a twofold increase. All but one line of each potato construct also showed an increase in tuber ascorbate of up to threefold. Interestingly, in tomato fruit, increased ascorbate was associated with loss of seed and the jelly of locular tissue surrounding the seed which was not seen in strawberry. In both strawberry and tomato, an increase in polyphenolic content was associated with increased ascorbate. These results show that GGP can be used to raise significantly ascorbate concentration in commercially significant edible crops. © 2011 The Authors. Plant Biotechnology Journal © 2011 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

21 CFR 182.8013 - Ascorbic acid.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ascorbic acid. 182.8013 Section 182.8013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8013 Ascorbic acid. (a...

21 CFR 182.8013 - Ascorbic acid.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ascorbic acid. 182.8013 Section 182.8013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8013 Ascorbic acid. (a...

21 CFR 182.8013 - Ascorbic acid.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ascorbic acid. 182.8013 Section 182.8013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8013 Ascorbic acid. (a...

21 CFR 182.8013 - Ascorbic acid.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ascorbic acid. 182.8013 Section 182.8013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8013 Ascorbic acid. (a...

Vitamin C acts as radiation-protecting agent

NASA Astrophysics Data System (ADS)

Platzer, Isabel; Getoff, Nikola

1998-01-01

It is well known that vitamin C (L-ascorbic acid) is a very efficient, water soluble antioxidant. Its multifunctional biological and biochemical activities are rather well established in the last few decades (e.g. Sies and Stahl, 1995; Meydani et al., 1995; NRC, 1989. In the present letter we are reporting briefly the pronounced radiation-protecting properties of ascorbate (AH -) observed on bacteria ( E. coli AB1157) as well as on cultured cells (SCC VII, eukaryotic cells).

Ascorbic Acid Metabolism in Pea Seedlings. A Comparison of d-Glucosone, l-Sorbosone, and l-Galactono-1,4-Lactone as Ascorbate Precursors1

PubMed Central

Pallanca, Jane E.; Smirnoff, Nicholas

1999-01-01

l-Ascorbic acid (AsA) accumulates in pea (Pisum sativum L.) seedlings during germination, with the most rapid phase of accumulation coinciding with radicle emergence. Monodehydroascorbate reductase and dehydroascorbic acid reductase were active in the embryonic axes before AsA accumulation started, whereas AsA oxidase and AsA peroxidase activities increased in parallel with AsA. Excised embryonic axes were used to investigate the osone pathway of AsA biosynthesis, in which d-glucosone and l-sorbosone are the proposed intermediates. [U-14C]Glucosone was incorporated into AsA and inhibited the incorporation of [U-14C]glucose (Glc) into AsA. A higher d-glucosone concentration (5 mm) inhibited AsA accumulation. l-Sorbosone did not affect AsA pool size but caused a small inhibition in the incorporation of [U-14C]Glc into AsA. Oxidase and dehydrogenase activities capable of converting Glc or Glc-6-phosphate to glucosone were not detected in embryonic axis extracts. The osones are therefore unlikely to be physiological intermediates of AsA biosynthesis. l-Galactono-1,4-lactone, recently proposed as the AsA precursor (G.L. Wheeler, M.A. Jones, N. Smirnoff [1998] Nature 393: 365–369), was readily converted to AsA by pea embryonic axes. Although l-galactono-1,4-lactone did not inhibit [14C]Glc incorporation into AsA, this does not mean that it is not a precursor, because competition between endogenous and exogenous pools was minimized by its very small pool size and rapid metabolism. PMID:10364396

Expression profiling of ascorbic acid-related genes during tomato fruit development and ripening and in response to stress conditions

USDA-ARS?s Scientific Manuscript database

L-Ascorbate (the reduced form of Vitamin C) participates in diverse biological processes including pathogen defense mechanisms, the modulation of plant growth and morphology and also acts as an enzyme cofactor, and redox status indicator. One of its chief biological functions is as an antioxidant. L...

The missing step of the L-galactose pathway of ascorbate biosynthesis in plants, an L-galactose guanyltransferase, increases leaf ascorbate content.

PubMed

Laing, William A; Wright, Michele A; Cooney, Janine; Bulley, Sean M

2007-05-29

The gene for one postulated enzyme that converts GDP-L-galactose to L-galactose-1-phosphate is unknown in the L-galactose pathway of ascorbic acid biosynthesis and a possible candidate identified through map-based cloning is the uncharacterized gene At4g26850. We identified a putative function for At4g26850 using PSI-Blast and motif searching to show it was a member of the histidine triad superfamily, which includes D-galactose uridyltransferase. We cloned and expressed this Arabidopsis gene and the homologous gene from Actinidia chinensis in Escherichia coli and assayed the expressed protein for activities related to converting GDP-L-galactose to L-galactose-1-P. The expressed protein is best described as a GDP-L-galactose-hexose-1-phosphate guanyltransferase (EC 2.7.7.), catalyzing the transfer of GMP from GDP-l-galactose to a hexose-1-P, most likely D-mannose-1-phosphate in vivo. Transient expression of this A. chinensis gene in tobacco leaves resulted in a >3-fold increase in leaf ascorbate as well as a 50-fold increase in GDP-L-galactose-D-mannose-1-phosphate guanyltransferase activity.

The missing step of the l-galactose pathway of ascorbate biosynthesis in plants, an l-galactose guanyltransferase, increases leaf ascorbate content

PubMed Central

Laing, William A.; Wright, Michele A.; Cooney, Janine; Bulley, Sean M.

2007-01-01

The gene for one postulated enzyme that converts GDP-l-galactose to l-galactose-1-phosphate is unknown in the l-galactose pathway of ascorbic acid biosynthesis and a possible candidate identified through map-based cloning is the uncharacterized gene At4g26850. We identified a putative function for At4g26850 using PSI-Blast and motif searching to show it was a member of the histidine triad superfamily, which includes d-galactose uridyltransferase. We cloned and expressed this Arabidopsis gene and the homologous gene from Actinidia chinensis in Escherichia coli and assayed the expressed protein for activities related to converting GDP-l-galactose to l-galactose-1-P. The expressed protein is best described as a GDP-l-galactose-hexose-1-phosphate guanyltransferase (EC 2.7.7.), catalyzing the transfer of GMP from GDP-l-galactose to a hexose-1-P, most likely d-mannose-1-phosphate in vivo. Transient expression of this A. chinensis gene in tobacco leaves resulted in a >3-fold increase in leaf ascorbate as well as a 50-fold increase in GDP-l-galactose-d-mannose-1-phosphate guanyltransferase activity. PMID:17485667

Treatment of Irradiated Mice with High-Dose Ascorbic Acid Reduced Lethality

PubMed Central

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. PMID:25651298

Rapid determination of thiamine, riboflavin, niacinamide, pantothenic acid, pyridoxine, folic acid and ascorbic acid in Vitamins with Minerals Tablets by high-performance liquid chromatography with diode array detector.

PubMed

Jin, Pengfei; Xia, Lufeng; Li, Zheng; Che, Ning; Zou, Ding; Hu, Xin

2012-11-01

A simple, isocratic, and stability-indicating high-performance liquid chromatography (HPLC) method has been developed for the rapid determination of thiamine (VB(1)), niacinamide (VB(3)), pyridoxine (VB(6)), ascorbic acid (VC), pantothenic acid (VB(5)), riboflavin (VB(2)) and folic acid (VB(9)) in Vitamins with Minerals Tablets (VMT). An Alltima C(18) column (250 mm × 4.6 mm i.d., 5 μm) was used for the separation at ambient temperature, with 50mM ammonium dihydrogen phosphate (adjusting with phosphoric acid to pH 3.0) and acetonitrile as the mobile phase at the flow rate of 0.5 ml min(-1). VB(1), VB(3), VB(6), VC and VB(5) were extracted with a solution containing 0.05% phosphoric acid (v/v) and 0.3% sodium thiosulfate (w/v), and were then simultaneously analyzed by using the mobile phase of phosphate buffer-acetonitrile (95:5, v/v), while VB(2) and VB(9) were extracted with a solution containing 0.5% ammonium hydroxide solution (v/v), and were then simultaneously analyzed by using the mobile phase of phosphate buffer-acetonitrile (85:15, v/v). The detection wavelengths were 275 nm for VB(1), VB(3), VB(6), VC, 210 nm for VB(5), and 282 nm for VB(2) and VB(9). The method showed good system suitability, sensitivity, linearity, specificity, precision, stability and accuracy. All the seven water-soluble vitamins were well separated from other ingredients and degradation products. Method comparison indicated good concordance between the developed method and the USP method. The developed method was reliable and convenient for the rapid determination of VB(1), VB(3), VB(6), VC, VB(5), VB(2) and VB(9) in VMT. Copyright © 2012 Elsevier B.V. All rights reserved.

Evaluation of the genotype, environment and their interaction on carotenoid and ascorbic acid accumulation in tomato germplasm.

PubMed

Roselló, Salvador; Adalid, Ana Maria; Cebolla-Cornejo, Jaime; Nuez, Fernando

2011-04-01

Tomatoes are an important source of antioxidants (carotenoids, vitamin C, etc.) owing to their high level of consumption. There is great interest in developing cultivars with increased levels of lycopene, β-carotene or L-ascorbic acid. There is necessary to survey new sources of variation. In this study, the potential of improvement for each character in tomato breeding programmes, in a single or joint approach, and the nature of genotype (G), environment (E) and G × E interaction effects in the expression of these characters were investigated. The content of lycopene, β-carotene and ascorbic acid determined was very high in some phenotypes (up to 281, 35 and 346 mg kg(-1) respectively). The important differences in the three environments studied (with some stressing conditions in several situations) had a remarkable influence in the phenotypic expression of the functional characters evaluated. Nevertheless, the major contribution came from the genotypic effect along with a considerable G × E interaction. The joint accumulation of lycopene and β-carotene has a high genetic component. It is possible to select elite genotypes with high content of both carotenoids in tomato breeding programmes but multi-environment trials are recommended. The improvement of ascorbic acid content is more difficult because the interference of uncontrolled factors mask the real genetic potential. Among the accessions evaluated, there are four accessions with an amazing genetic potential for functional properties that can be used as donor parents in tomato breeding programmes or for direct consumption in quality markets. Copyright © 2011 Society of Chemical Industry.

Ontogenetic changes in vitamin C in selected rice varieties

USDA-ARS?s Scientific Manuscript database

Vitamin C (L-ascorbic acid, AsA) is a key antioxidant for both plants and animals. In plants, AsA is involved in several key physiological processes including photosynthesis, cell expansion, cell division, growth, flowering, and senescence. In addition, AsA is an enzyme cofactor and a regulator of...

Toxicity of nickel and silver to Nostoc muscorum: interaction with ascorbic acid, glutathione, and sulfur-containing amino acids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rai, L.C.; Raizada, M.

1987-08-01

Exposure of Nostoc muscorum to different concentrations of Ni and Ag brought about reduction in growth, carbon fixation, heterocyst production, and nitrogenase activity and increase in the loss of ions (K+, Na+). In an attempt to ameliorate the toxicity of test metals by ascorbic acid, glutathione, and sulfur-containing amino acids (L-cysteine and L-methionine), it was found that the level of protection by ascorbic acid and glutathione was more for Ag than Ni. However, metal-induced inhibition of growth and carbon fixation was equally ameliorated by methionine. But the level of protection by cysteine was quite different, i.e., 27% for Ni andmore » 22% for Ag. Protection of metal toxicity in N. muscorum by amino acids lends further support to self-detoxifying ability of cyanobacteria because they are known to synthesize all essential amino acids.« less

Sodium Bicarbonate-Ascorbic Acid Combination for Prevention of Contrast-Induced Nephropathy in Chronic Kidney Disease Patients Undergoing Catheterization.

PubMed

Komiyama, Kota; Ashikaga, Takashi; Inagaki, Dai; Miyabe, Tomonori; Arai, Marina; Yoshida, Kiyotaka; Miyazawa, Satoshi; Nakada, Akihiro; Kawamura, Iwanari; Masuda, Shinichiro; Nagamine, Sho; Hojo, Rintaro; Aoyama, Yuya; Tsuchiyama, Takaaki; Fukamizu, Seiji; Shibui, Takashi; Sakurada, Harumizu

2017-01-25

Sodium bicarbonate and ascorbic acid have been proposed to prevent contrast-induced nephropathy (CIN). The present study evaluated the effect of their combined use on CIN incidence.Methods and Results:We prospectively enrolled 429 patients with chronic kidney disease (CKD: baseline estimated glomerular filtration rate <60 mL/min/1.73 m 2 ) prior to elective coronary catheterization. CIN was defined as absolute (≥0.5 mg/dL) or relative (≥25%) increase in serum creatinine within 72 h. In the saline hydration (n=218) and combined sodium bicarbonate+ascorbic acid (n=211) groups, a total of 1,500-2,500 mL 0.9% saline was given before and after the procedure. In addition, the combination group received 20 mEq sodium bicarbonate and 3 g ascorbic acid i.v. before the procedure, followed by 2 g ascorbic acid after the procedure and a further 2 g after 12 h. There were no significant differences between the basic characteristics and contrast volume in the 2 groups. CIN occurred in 19 patients (8.7%) in the saline group, and in 6 patients (2.8%) in the combined treatment group (P=0.008). Combined sodium bicarbonate and ascorbic acid could prevent CIN following catheterization in CKD patients.

Understanding the degradation of ascorbic acid and glutathione in relation to the levels of oxidative stress biomarkers in broccoli (Brassica oleracea L. italica cv. Bellstar) during storage and mechanical processing.

PubMed

Raseetha, Siva; Leong, Sze Ying; Burritt, David John; Oey, Indrawati

2013-06-01

The purpose of this research was to understand the degradation of ascorbic acid and glutathione content in broccoli florets (Brassica oleracea L. italica cv. Bellstar) during prolonged storage and subsequent mechanical processing. The initial content of total ascorbic acid and glutathione in broccoli florets averaged at 5.18 ± 0.23 and 0.70 ± 0.03 μmol/g fresh weight, respectively. Results showed that the content of ascorbic acid and glutathione in broccoli degraded during storage at 23°C, for at least 4.5-fold after 6 days of storage. On each day of storage, broccoli florets were mechanically processed, but the content of total ascorbic acid and glutathione was not significantly affected. When the mechanically processed broccoli florets were further incubated for up to 6h, the amount of ascorbic acid was greatly reduced as compared to glutathione. To obtain an in-depth understanding on the degradation of ascorbic acid and glutathione, the activity of enzymes involved in plant antioxidative system via ascorbate-glutathione cycle, as a response towards oxidative stress that took place during storage was determined in this study. The content of total ascorbic acid and glutathione in broccoli florets before and after mechanical processing were found to decrease concurrently with the activity of ascorbic acid peroxidase and glutathione reductase over the experimental storage duration. Meanwhile, the effect of oxidative stress on the content of ascorbic acid and glutathione was apparent during the 6h of incubation after mechanical processing. This phenomenon was demonstrated by the level of oxidative stress biomarkers examined, in which the formation of lipid peroxides, protein carbonyls and DNA oxidised products was positively associated with the degradation of total ascorbic acid and glutathione. Copyright © 2012 Elsevier Ltd. All rights reserved.

Dose of 3-methylcholanthrene enhances vitamin C accumulation and mRNA expression of its transporter in the liver of ODS rats and in HepG2 cells.

PubMed

Sone, Yasuko; Ueta, Etsuko; Sannomaru, Yasuko; Miyake, Noriko; Sone, Hirohito; Otsuka, Yuzuru; Kondo, Kazuo; Kurata, Tadao; Suzuki, Emiko

2011-01-01

Polycyclic aromatic hydrocarbon (PAH) compounds including 3-methylcholanthrene induce harmful reactive intermediates and reactive oxygen species. This study reports the effect of 3-methylcholanthrene on the accumulation of vitamin C and the expression of vitamin C transporters. ODS rats were given l-ascorbic acid daily and intraperitoneal injections of 10 mg 3-methylcholanthrene in total. On day 10, vitamin C concentrations and the expression of vitamin C transporter in the tissues were measured. As a result, the levels of sodium-dependent vitamin C transporter (SVCTs) 1 and the l-ascorbic acid concentration in 3-methylcholanthrene-treated livers and hepatocytes have increased significantly. However, the content of vitamin C in the urine and TBARS in the liver have not changed. These results suggest that the administration of 3-methylcholanthrene elevates the requirement for vitamin C via (SVCTs) 1 due to xenobitics-metabolizing, such as the induction of cytochrome P450 family. Copyright © 2011 Wiley Periodicals, Inc.

Comparison of the anti-scorbutic activity of L-ascorbic acid and Ester C in the non-ascorbate synthesizing Osteogenic Disorder Shionogi (ODS) rat.

PubMed

Verlangieri, A J; Fay, M J; Bannon, A W

1991-01-01

The Osteogenic Disorder Shionogi (ODS) rat, Clea Inc., Tokyo, Japan lacks the ability to synthesize L-ascorbic acid (AA). As with man, monkey and the guinea pig, this rat lacks L-gulonolactone oxidase necessary for the synthesis of AA from glucose. This study shows this animal to be an alternative to the guinea pig in AA studies. The anti-scorbutic potency of Ester C (EC), a calcium ascorbate and calcium threonate mixture, was compared with an AA dose of equal ascorbate activity equivalents (AAE) for anti-scorbutic activity in the ODS rat. The minimal anti-scorbutic dose of EC was determined to be 0.44 mg/kg/day (AAE), while an AA dose of 0.51 mg/kg/day (AAE) was not anti-scorbutic in a 24 day study. At 24 days EC rats gained 125% of initial body weight (BW) and the AA rats only 45% BW. Scorbutic signs at 24 days were scored on a 0 (min) to 3 (max) scale. The EC/AA ratio scores were: hemorrhage 0/1.4, behavior change 0/2.0, piloerection 0/2.2, mobility 0.4/2.2, dysbasia 0.6/2.8 and ataxia 0.4/1.0. Pearson's correlation coefficient for BW versus AAE was r = .34 for the AA group and r = .90 for the EC group. The morbidity index for EC was 0/5 and for the AA group 2/5. The AAE dose of AA which was 16% higher/day than the EC AAE dose was not anti-scorbutic, while the EC dose was anti-scorbutic. EC rats had 3.5X greater weight gain, a sensitive indicator of scurvy, than the AA rats. EC rats had 3-4 times less, if any, scorbutic signs than AA rats. The results clearly show that, based on ascorbate activity equivalents, EC has more available ascorbate activity/potency than AA. The mechanism of this increased potency is believed to be due to the facilitated transport of AAE into the cell by the threonate (a normal in vivo metabolite of AA) present in the EC product. In addition, previous studies have shown EC (AAE) to be higher in plasma and excreted less rapidly than the AAE derived from AA administered orally.

Vitamin B12 deficiency results in severe oxidative stress, leading to memory retention impairment in Caenorhabditis elegans.

PubMed

Bito, Tomohiro; Misaki, Taihei; Yabuta, Yukinori; Ishikawa, Takahiro; Kawano, Tsuyoshi; Watanabe, Fumio

2017-04-01

Oxidative stress is implicated in various human diseases and conditions, such as a neurodegeneration, which is the major symptom of vitamin B 12 deficiency, although the underlying disease mechanisms associated with vitamin B 12 deficiency are poorly understood. Vitamin B 12 deficiency was found to significantly increase cellular H 2 O 2 and NO content in Caenorhabditis elegans and significantly decrease low molecular antioxidant [reduced glutathione (GSH) and L-ascorbic acid] levels and antioxidant enzyme (superoxide dismutase and catalase) activities, indicating that vitamin B 12 deficiency induces severe oxidative stress leading to oxidative damage of various cellular components in worms. An NaCl chemotaxis associative learning assay indicated that vitamin B 12 deficiency did not affect learning ability but impaired memory retention ability, which decreased to approximately 58% of the control value. When worms were treated with 1mmol/L GSH, L-ascorbic acid, or vitamin E for three generations during vitamin B 12 deficiency, cellular malondialdehyde content as an index of oxidative stress decreased to the control level, but the impairment of memory retention ability was not completely reversed (up to approximately 50%). These results suggest that memory retention impairment formed during vitamin B 12 deficiency is partially attributable to oxidative stress. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Re-evaluating the role of phenolic glycosides and ascorbic acid in ozone scavenging in the leaf apoplast of Arabidopsis thaliana L

USDA-ARS?s Scientific Manuscript database

To determine if membrane-bound G-proteins are involved in the regulation of defense responses against ozone in the leaf apoplast, the apoplastic concentrations of ascorbic acid and phenolic glycosides in Arabidopsis thaliana L. lines with null mutations in the alpha- and beta-subunits were compared ...

21 CFR 182.3013 - Ascorbic acid.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ascorbic acid. 182.3013 Section 182.3013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 182.3013 Ascorbic...

Amino Acid and Vitamin Requirements of Several Bacteroides Strains

PubMed Central

Quinto, Grace

1966-01-01

Nutritional studies were performed on nine Bacteroides strains, by use of the methodology and media of anaerobic rumen microbiology. Ristella perfoetens CCI required l-arginine hydrochloride, l-tryptophan, l-leucine, l-histidine hydrochloride, l-cysteine hydrochloride, dl-valine, dl-tyrosine, and the vitamin calcium-d-pantothenate, since scant turbidity developed in media without these nutrients. R. perfoetens was stimulated by glycine, dl-lysine hydrochloride, dl-isoleucine, l-proline, l-glutamic acid, dl-alanine, dl-phenylalanine, dl-methionine, and the vitamins nicotinamide and p-aminobenzoic acid, since maximal turbidity developed more slowly in media without these nutrients than in complete medium. Medium A-23, which was devised for R. perfoetens, contained salts, 0.0002% nicotinamide and calcium d-pantothenate, 0.00001% p-aminobenzoic acid, 0.044% l-tryptophan, 0.09% l-glutamic acid, and 0.1% of the other 13 amino acids listed above. Zuberella clostridiformis and seven strains of R. pseudoinsolita did not require vitamins, and showed no absolute requirement for any one amino acid. Various strains produced maximal turbidity more slowly in media deficient in l-proline, glycine, l-glutamic acid, dl-serine, l-histidine hydrochloride, dl-alanine, or l-cysteine hydrochloride, than in complete medium. These eight strains grew optimally in medium A-23 plus 0.1% dl-serine but without vitamins. PMID:16349673

Ascorbic acid transported by sodium-dependent vitamin C transporter 2 stimulates steroidogenesis in human choriocarcinoma cells.

PubMed

Wu, Ximei; Iguchi, Takuma; Itoh, Norio; Okamoto, Kousuke; Takagi, Tatsuya; Tanaka, Keiichi; Nakanishi, Tsuyoshi

2008-01-01

Reduced vitamin C [ascorbic acid (AA)], which is taken up into cells by sodium-dependent vitamin C transporter (SVCT) 1 and 2, is believed to be important for hormone synthesis, but its role in generating placental steroids needed to maintain pregnancy and fetal development is not clear. To determine the steroidogenic effect of AA and the role of SVCT2 in AA-induced steroidogenesis, we tested the effects of AA treatment and SVCT2 knockdown on steroidogenesis in human choriocarcinoma cell lines. AA treatment of JEG-3, BeWo, and JAR cells for 48-h dose dependently increased progesterone and estradiol levels. In JEG-3 cells, AA increased the mRNA expression of P450 cholesterol side-chain cleavage enzyme, 3beta-hydroxysteroid dehydrogenase type 1, and aromatase, key enzymes for steroidogenesis. Stable knockdown of SVCT2 in JEG-3 cells by retrovirally mediated RNA interference decreased the maximal velocity of AA uptake by approximately 50%, but apparent affinity values were not affected. SVCT2 knockdown in JEG-3 cells significantly suppressed the AA-induced mRNA expression of placental P450 cholesterol side-chain cleavage enzyme, 3beta-hydroxysteroid dehydrogenase type 1, and aromatase. This suppression of the AA-induced mRNA expression of steroidogenic enzymes subsequently decreased progesterone and estradiol production. In addition, inhibition of MAPK kinase-ERK signaling, which is a major pathway for AA-regulated gene expression, failed to affect AA-induced steroidogenesis. Our observations indicate that SVCT2-mediated AA uptake into cells is necessary for AA-induced steroidogenesis in human choriocarcinoma cell, but MAPK kinase-ERK signaling is not involved in AA-induced steroidogenesis.

Osteo-maturation of adipose-derived stem cells required the combined action of vitamin D3, beta-glycerophosphate, and ascorbic acid.

PubMed

Gupta, Anurag; Leong, David Tai; Bai, Hui Fen; Singh, Shiv Brat; Lim, Thiam-Chye; Hutmacher, Dietmar Werner

2007-10-12

This study investigated the effects of various components [vitamin D3 (VD3), beta-glycerophosphate (BGP), and ascorbic acid (AA)] on the potential of human adipose-derived progenitor cells (ADPCs) to transdifferentiate into osteoblast-like cells. ADPCs were induced under four different supplement groups: (1) VD3+BGP+AA, (2) VD3 alone, (3) BGP+AA, and (4) no VD3, BGP or AA. Mineralization studies and presence of bone matrix-related proteins by immunostaining showed that the Group 1 ADPCs showed their ability to undergo osteoblastic differentiation. Further evaluation was made by estimation of levels of RUNX-2 and TAZ genes. Group 1 ADPCs showed the consistent expression of RUNX-2 and TAZ levels over the study period of 28days. The study showed good correlation among various parameters evaluated to conclude that ADPCs could be an alternative source for generating osteoblast-like cells.

[Effect of temperature on the aerobic degradation of vitamin C in citric fruit juices].

PubMed

Alvarado, J D; Palacios Viteri, N

1989-12-01

By means of the method of the 2,4-dinitrophenylhydrazine the total ascorbic acid content in lima, lemon, tangerine and grapefruit juices, fresh and kept at four temperatures and different times, was determined. It was confirmed that in all the cases, the aerobic degradation of ascorbic acid follows a kinetic first order and that the values of the reaction rate are different between species and even between varieties of lemon and tangerine. The values of the equation terms are reported, and examples of application given. Within a range from 20 degrees to 92 degrees C, the effect of temperature on the velocity of the ascorbic acid degradation is described satisfactorily following the Arrhenius equation, in accordance with which, the corresponding values of activation energy are calculated to compare them with other published values. With the simple application of the method, in two steps, and considering that the L-ascorbic acid and the L-dehydroascorbic acid are predominant, the results can be used to calculate the vitamin C losses in citric fruit juices, indicated when they are processed by traditional thermal treatments.

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

ERIC Educational Resources Information Center

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…

Comparative study of the anti-HIV activities of ascorbate and thiol-containing reducing agents in chronically HIV-infected cells.

PubMed

Harakeh, S; Jariwalla, R J

1991-12-01

To elucidate the action of vitamin C on pathogenic human retroviruses, we investigated and compared the effects of noncytoxic concentrations of ascorbic acid (AA), its calcium salt (Ca-ascorbate), and two thiol-based reducing agents [glutathione (GSH) and N-acetyl-L-cysteine (NAC)] against human immunodeficiency virus (HIV)-1 replication in chronically infected T lymphocytes. Ca-ascorbate reduced extracellular HIV reverse transcriptase (RT) activity by about the same magnitude as the equivalent dose of AA. Long-term experiments showed that continuous presence of ascorbate was necessary for HIV suppression. NAC (10 mmol/L) caused less than twofold inhibition of HIV RT and conferred a synergistic effect (approximately eightfold inhibition) when tested simultaneously with AA (0.426 mmol/L). In contrast, nonesterified GSH (less than or equal to 1.838 mmol/L) had no effect on RT concentrations and did not potentiate the anti-HIV effect of AA. These results further support the potent antiviral activity of ascorbate and suggest its therapeutic value in controlling HIV infection in combination with thiols.

SVCT-2 determines the sensitivity to ascorbate-induced cell death in cholangiocarcinoma cell lines and patient derived xenografts.

PubMed

Wang, Changzheng; Lv, Hongwei; Yang, Wen; Li, Ting; Fang, Tian; Lv, Guishuai; Han, Qin; Dong, Liwei; Jiang, Tianyi; Jiang, Beige; Yang, Guangshun; Wang, Hongyang

2017-07-10

Cholangiocarcinoma (CC) is a devastating malignancy with late diagnosis and poor response to conventional chemotherapy. Recent studies have revealed anti-cancer effect of vitamin C (l-ascorbic acid, ascorbate) in several types of cancer. However, the effect of l-ascorbic acid (AA) in CC remains elusive. Herein, we demonstrated that AA induced cytotoxicity in CC cells by generating intracellular reactive oxygen species (ROS), and subsequently DNA damage, ATP depletion, mTOR pathway inhibition. Moreover, AA worked synergistically with chemotherapeutic agent cisplatin to impair CC cells growth both in vitro and in vivo. Intriguingly, sodium-dependent vitamin C transporter 2 (SVCT-2) expression was inversely correlated with IC50 values of AA. Knockdown of SVCT-2 dramatically alleviated DNA damage, ATP depletion, and inhibition of mTOR pathway induced by AA. Furthermore, SVCT-2 knockdown endowed CC cells with the resistance to AA treatment. Finally, the inhibitory effects of AA were further confirmed in patient-derived CC xenograft models. Thus, our results unravel therapeutic potential of AA alone or in combination with cisplatin for CC. SVCT2 expression level may serve as a positive outcome predictor for AA treatment in CC. Copyright © 2017 Elsevier B.V. All rights reserved.

21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

Code of Federal Regulations, 2013 CFR

2013-04-01

... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex...: (a) The additive is the product of the controlled reaction between ascorbic acid and nicotinamide...

21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

Code of Federal Regulations, 2012 CFR

2012-04-01

... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex...: (a) The additive is the product of the controlled reaction between ascorbic acid and nicotinamide...

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, E.H.

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 correspondingmore » 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.« less

21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

Code of Federal Regulations, 2014 CFR

2014-04-01

... (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR 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 conditions: (a) The additive is the product of...

Rapid Quantitation of Ascorbic and Folic Acids in SRM 3280 Multivitamin/Multielement Tablets using Flow-Injection Tandem Mass Spectrometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhandari, Deepak; Kertesz, Vilmos; Van Berkel, Gary J

RATIONALE: Ascorbic acid (AA) and folic acid (FA) are water-soluble vitamins and are usually fortified in food and dietary supplements. For the safety of human health, proper intake of these vitamins is recommended. Improvement in the analysis time required for the quantitative determination of these vitamins in food and nutritional formulations is desired. METHODS: A simple and fast (~5 min) in-tube sample preparation was performed, independently for FA and AA, by mixing extraction solvent with a powdered sample aliquot followed by agitation, centrifugation, and filtration to recover an extract for analysis. Quantitative detection was achieved by flow-injection (1 L injectionmore » volume) electrospray ionization tandem mass spectrometry (ESI-MS/MS) in negative ion mode using the method of standard addition. RESULTS: Method of standard addition was employed for the quantitative estimation of each vitamin in a sample extract. At least 2 spiked and 1 non-spiked sample extract were injected in triplicate for each quantitative analysis. Given an injection-to-injection interval of approximately 2 min, about 18 min was required to complete the quantitative estimation of each vitamin. The concentration values obtained for the respective vitamins in the standard reference material (SRM) 3280 using this approach were within the statistical range of the certified values provided in the NIST Certificate of Analysis. The estimated limit of detections of FA and AA were 13 and 5.9 ng/g, respectively. CONCLUSIONS: Flow-injection ESI-MS/MS was successfully applied for the rapid quantitation of FA and AA in SRM 3280 multivitamin/multielement tablets.« less

Antioxidant poly(lactic-co-glycolic) acid nanoparticles made with α-tocopherol-ascorbic acid surfactant.

PubMed

Astete, Carlos E; Dolliver, Debra; Whaley, Meocha; Khachatryan, Lavrent; Sabliov, Cristina M

2011-12-27

The goal of the study was to synthesize a surfactant made of α-tocopherol (vitamin E) and ascorbic acid (vitamin C) of antioxidant properties dubbed as EC, and to use this surfactant to make poly(lactic-co-glycolic) acid (PLGA) nanoparticles. Self-assembled EC nanostructures and PLGA-EC nanoparticles were made by nanoprecipitation, and their physical properties (size, size distribution, morphology) were studied at different salt concentrations, surfactant concentrations, and polymer/surfactant ratios. EC surfactant was shown to form self-assembled nanostructures in water with a size of 22 to 138 nm in the presence of sodium chloride, or 12 to 31 nm when synthesis was carried out in sodium bicarbonate. Polymeric PLGA-EC nanoparticles presented a size of 90 to 126 nm for 40% to 120% mass ratio PLGA to surfactant. For the same mass ratios, the PLGA-Span80 formed particles measured 155 to 216 nm. Span80 formed bilayers, whereas EC formed monolayers at the interfaces. PLGA-EC nanoparticles and EC showed antioxidant activity based on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay measurements using UV and EPR techniques, antioxidant activity which is not characteristic to commercially available Span80. The thiobarbituric acid reactive substances (TBARS) assay for lipid peroxidation showed that PLGA nanoparticles with EC performed better as antioxidants than the EC nanoassembly or the free vitamin C. Nanoparticles were readily internalized by HepG2 cells and were localized in the cytoplasm. The newly synthesized EC surfactant was therefore found successful in forming uniform, small size polymeric nanoparticles of intrinsic antioxidant properties.

Elevating vitamin C content via overexpression of myo-inositol oxygenase and l-gulono-1,4-lactone oxidase in Arabidopsis leads to enhanced biomass and tolerance to abiotic stresses.

PubMed

Lisko, Katherine A; Torres, Raquel; Harris, Rodney S; Belisle, Melinda; Vaughan, Martha M; Jullian, Berangère; Chevone, Boris I; Mendes, Pedro; Nessler, Craig L; Lorence, Argelia

2013-12-01

l-Ascorbic acid (vitamin C) is an abundant metabolite in plant cells and tissues. Ascorbate functions as an antioxidant, as an enzyme cofactor, and plays essential roles in multiple physiological processes including photosynthesis, photoprotection, control of cell cycle and cell elongation, and modulation of flowering time, gene regulation, and senescence. The importance of this key molecule in regulating whole plant morphology, cell structure, and plant development has been clearly established via characterization of low vitamin C mutants of Arabidopsis , potato, tobacco, tomato, and rice. However, the consequences of elevating ascorbate content in plant growth and development are poorly understood. Here we demonstrate that Arabidopsis lines over-expressing a myo -inositol oxygenase or an l-gulono-1,4-lactone oxidase, containing elevated ascorbate, display enhanced growth and biomass accumulation of both aerial and root tissues. To our knowledge this is the first study demonstrating such a marked positive effect in plant growth in lines engineered to contain elevated vitamin C content. In addition, we present evidence showing that these lines are tolerant to a wide range of abiotic stresses including salt, cold, and heat. Total ascorbate content of the transgenic lines remained higher than those of controls under the abiotic stresses tested. Interestingly, exposure to pyrene, a polycyclic aromatic hydrocarbon and known inducer of oxidative stress in plants, leads to stunted growth of the aerial tissue, reduction in the number of root hairs, and inhibition of leaf expansion in wild type plants, while these symptoms are less severe in the over-expressers. Our results indicate the potential of this metabolic engineering strategy to develop crops with enhanced biomass, abiotic stress tolerance, and phytoremediation capabilities.

Study of L-ascorbic acid (vitamin C)/H 2O mixture across glass transition

NASA Astrophysics Data System (ADS)

Migliardo, F.; Branca, C.; Faraone, A.; Magazù, S.; Migliardo, P.

2001-07-01

In this paper, we report quasi elastic neutron scattering (QENS) spectra of vitamin C aqueous solutions, obtained using MIBEMOL spectrometer (LLB). The main purpose of this work is to characterize the relaxational and vibrational properties of the Vitamin C/H 2O system below and above the glass transition temperature by analysing the low-frequency neutron scattering spectra. The determination of the relative weight of vibrational over relaxational contributions allows to get information on the fragility degree of this peculiar hydrogen-bond system.

Regulation of L-ascorbic acid content in strawberry fruits

PubMed Central

Cruz-Rus, Eduardo; Amaya, Iraida; Sánchez-Sevilla, José F.; Botella, Miguel A.; Valpuesta, Victoriano

2011-01-01

Plants have several L-ascorbic acid (AsA) biosynthetic pathways, but the contribution of each one to the synthesis of AsA varyies between different species, organs, and developmental stages. Strawberry (Fragaria×ananassa) fruits are rich in AsA. The pathway that uses D-galacturonate as the initial substrate is functional in ripe fruits, but the contribution of other pathways to AsA biosynthesis has not been studied. The transcription of genes encoding biosynthetic enzymes such as D-galacturonate reductase (FaGalUR) and myo-inositol oxygenase (FaMIOX), and the AsA recycling enzyme monodehydroascorbate reductase (FaMDHAR) were positively correlated with the increase in AsA during fruit ripening. Fruit storage for 72 h in a cold room reduced the AsA content by 30%. Under an ozone atmosphere, this reduction was 15%. Ozone treatment increased the expression of the FaGalUR, FaMIOX, and L-galactose-1-phosphate phosphatase (FaGIPP) genes, and transcription of the L-galactono-1,4-lactone dehydrogenase (FaGLDH) and FAMDHAR genes was higher in the ozone-stored than in the air-stored fruits. Analysis of AsA content in a segregating population from two strawberry cultivars showed high variability, which did not correlate with the transcription of any of the genes studied. Study of GalUR protein in diverse cultivars of strawberry and different Fragaria species showed that a correlation between GalUR and AsA content was apparent in most cases, but it was not general. Three alleles were identified in strawberry, but any sequence effect on the AsA variability was eliminated by analysis of the allele-specific expression. Taken together, these results indicate that FaGalUR shares the control of AsA levels with other enzymes and regulatory elements in strawberry fruit. PMID:21561953

Experimental IR and Raman spectra and quantum chemical studies of molecular structures, conformers and vibrational characteristics of L-ascorbic acid and its anion and cation

NASA Astrophysics Data System (ADS)

Yadav, R. A.; Rani, P.; Kumar, M.; Singh, R.; Singh, Priyanka; Singh, N. P.

2011-12-01

IR and spectra of the L-ascorbic acid ( L-AA) also known as vitamin C have been recorded in the region 4000-50 cm -1. In order to make vibrational assignments of the observed IR and Raman bands computations were carried out by employing the RHF and DFT methods to calculate the molecular geometries and harmonic vibrational frequencies along with other related parameters for the neutral L-AA and its singly charged anionic ( L-AA -) and cationic ( L-AA +) species. Significant changes have been found for different characteristics of a number of vibrational modes. The four ν(O-H) modes of the L-AA molecule are found in the order ν(O 9-H 10) > ν(O 19-H 20) > ν(O 7-H 8) > ν(O 14-H 15) which could be due to complexity of hydrogen bonding in the lactone ring and the side chain. The C dbnd O stretching wavenumber ( ν46) decreases by 151 cm -1 in going from the neutral to the anionic species whereas it increases by 151 cm -1 in going from the anionic to the cationic species. The anionic radicals have less kinetic stabilities and high chemical reactivity as compared to the neutral molecule. It is found that the cationic radical of L-AA is kinetically least stable and chemically most reactive as compared to its neutral and anionic species.

Supplementation of ascorbic acid and alpha-tocopherol is useful to preventing bone loss linked to oxidative stress in elderly.

PubMed

Ruiz-Ramos, M; Vargas, L Alberto; Fortoul Van der Goes, T I; Cervantes-Sandoval, A; Mendoza-Nunez, V M

2010-06-01

To determine the effect of ascorbic acid and alpha-tocopherol on oxidative stress and bone mineral density (BMD) in elderly people. A double-blind, controlled clinical assay was carried out in a sample of 90 elderly subjects divided into three age-paired random groups with 30 subjects in each group. Group Tx0 received placebo, group Tx1 received 500 mg of ascorbic acid and 400 IU of alpha-tocopherol, whereas group Tx2 received 1,000 mg of ascorbic acid and 400 IU of alpha-tocopherol, for a 12-month period. We measured thiobarbituric acid reactive substances (TBARS), total antioxidant status (TAS), superoxide dismutase (SOD), and glutation peroxidase (GPx); BMD was obtained on DXA of hip and spine before and after the 12-month treatment period with supplementation of vitamins C and E. We found a positive correlation between hip-BMD and SOD (r = 0.298, p < 0.05) and GPx (r = 0.214, p < 0.05). Also, a significantly lower decrease of LPO (p < 0.05) was observed as linked with hip bone loss in the Tx2 group than in the Tx0 group. Our findings suggest that that administration of 1,000 mg of ascorbic acid together with 400 IU of alpha-tocopherol could be useful in preventing or aiding in the treatment of age-related osteoporosis.

Water-soluble vitamins.

PubMed

Konings, Erik J M

2006-01-01

because of their low sensitivity and poor selectivity. Pakin et al. proposed a post-column derivatization of pantothenic acid as a fluorescent compound and used this principle in a specific and sensitive method for the determination of free and bound pantothenic acid in a large variety of foods. A French laboratory invited European laboratories to participate in a series of collaborative studies for this method, which will be carried out in 2005/2006. A more sophisticated method was described by Mittermayer et al. They developed an LC-mass spectrometry (LC/MS) method for the determination of vitamin B5 in a wide range of fortified food products. Application of the method to various samples showed consistent results with those obtained by microbiology. Vitamin B6.-Method 2004.07, an LC method for the analysis of vitamin B6 in reconstituted infant formula, was published by Mann et al. In contrast with this method, which quantifies vitamin B6 after converting the phosphorylated and free vitamers into pyridoxine, Viñas et al. published an LC method which determines 6 vitamin B6 related compounds, the 3 B6 vitamers, their corresponding phosphorylated esters, and a metabolite. Accuracy was determined using 2 CRMs. Results were within the certified ranges. Vitamin C.-Franke et al. described an extensive study to vitamin C and flavonoid levels of fruits and vegetables consumed in Hawaii. Vitamin C was determined by measuring ascorbic acid in its reduced state by LC and coulometric detection along with UV absorbance detection at 245 nm. No attempts were made to assess levels of dehydroascorbic acid. Most recent research revealed that cell uptake of dehydroascorbic acid is unlikely to play a major role, which may explain the very low vitamin C activity of orally administered L-dehydroascorbic acid in rats. The food levels found by Franke et al. are variably lower, higher, or equal in comparison to other studies. Iwase described a method for the determination of ascorbic acid in

Inhibition of collagen synthesis by select calcium and sodium channel blockers can be mitigated by ascorbic acid and ascorbyl palmitate

PubMed Central

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

Inhibition of collagen synthesis by select calcium and sodium channel blockers can be mitigated by ascorbic acid and ascorbyl palmitate.

PubMed

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

Ascorbic Acid and the Brain: Rationale for the Use against Cognitive Decline

PubMed Central

Harrison, Fiona E.; Bowman, Gene L.; Polidori, Maria Cristina

2014-01-01

This review is focused upon the role of ascorbic acid (AA, vitamin C) in the promotion of healthy brain aging. Particular attention is attributed to the biochemistry and neuronal metabolism interface, transport across tissues, animal models that are useful for this area of research, and the human studies that implicate AA in the continuum between normal cognitive aging and age-related cognitive decline up to Alzheimer’s disease. Vascular risk factors and comorbidity relationships with cognitive decline and AA are discussed to facilitate strategies for advancing AA research in the area of brain health and neurodegeneration. PMID:24763117

The kinetics of oxidation of bilirubin and ascorbic acid in solution

NASA Astrophysics Data System (ADS)

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.

The invertebrate Caenorhabditis elegans biosynthesizes ascorbate

PubMed Central

Patananan, Alexander N.; Budenholzer, Lauren M.; Pedraza, Maria E.; Torres, Eric R.; Adler, Lital N.; Clarke, Steven G.

2015-01-01

L-ascorbate, commonly known as vitamin C, serves as an antioxidant and cofactor essential for many biological processes. Distinct ascorbate biosynthetic pathways have been established for animals and plants, but little is known about the presence or synthesis of this molecule in invertebrate species. We have investigated ascorbate metabolism in the nematode Caenorhabditis elegans, where this molecule would be expected to play roles in oxidative stress resistance and as cofactor in collagen and neurotransmitter synthesis. Using high-performance liquid chromatography and gas-chromatography mass spectrometry, we determined that ascorbate is present at low amounts in the egg stage, L1 larvae, and mixed animal populations, with the egg stage containing the highest concentrations. Incubating C. elegans with precursor molecules necessary for ascorbate synthesis in plants and animals did not significantly alter ascorbate levels. Furthermore, bioinformatic analyses did not support the presence in C. elegans of either the plant or the animal biosynthetic pathway. However, we observed the complete 13C-labeling of ascorbate when C. elegans was grown with 13C-labeled Escherichia coli as a food source. These results support the hypothesis that ascorbate biosynthesis in invertebrates may proceed by a novel pathway and lay the foundation for a broader understanding of its biological role. PMID:25668719

Effects of dietary chromium exposure to rockfish, Sebastes schlegelii are ameliorated by ascorbic acid.

PubMed

Kim, Jun-Hwan; Kang, Ju-Chan

2017-05-01

Juvenile rockfish Sebastes schlegelii (mean length 10.8±1.4cm, and mean weight 31.7±3.6g) were exposed for 4 weeks with the different levels of dietary chromium (Cr 6+ ) at 0, 120 and 240mg/L and ascorbic acids (AsA) at 100, 200 and 400mg/L. Significant accumulation occurred in specific tissues and hematological parameters were altered: red blood cell count, hematocrit, and hemoglobin increased; plasma components were altered including calcium, glucose, cholesterol, total protein, glutamic oxalate transaminase, and glutamic pyruvate transaminase. However, magnesium and alkaline phosphatase concentrations were unchanged. Ascorbic acids reduced both chromium uptake into tissues and altered hematological parameters. Copyright © 2017. Published by Elsevier Inc.

Effect of resveratrol or ascorbic acid on the stability of α-tocopherol in O/W emulsions stabilized by whey protein isolate: Simultaneous encapsulation of the vitamin and the protective antioxidant.

PubMed

Wang, Lei; Gao, Yahui; Li, Juan; Subirade, Muriel; Song, Yuanda; Liang, Li

2016-04-01

Food proteins have been widely used as carrier materials due to their multiple functional properties. Hydrophobic bioactives are generally dissolved in the oil phase of O/W emulsions. Ligand-binding properties provide the possibility of binding bioactives to the protein membrane of oil droplets. In this study, the influence of whey protein isolate (WPI) concentration and amphiphilic resveratrol or hydrophilic ascorbic acid on the decomposition of α-tocopherol in the oil phase of WPI emulsions is considered. Impact of ascorbic acid, in the continuous phase, on the decomposition depended on the vitamin concentration. Resveratrol partitioned into the oil-water interface and the cis-isomer contributed most of the protective effect of this polyphenol. About 94% of α-tocopherol and 50% of resveratrol were found in the oil droplets stabilized by 0.01% WPI. These results suggest the feasibility of using the emulsifying and ligand-binding properties of WPI to produce carriers for simultaneous encapsulation of bioactives with different physicochemical properties. Copyright © 2015 Elsevier Ltd. All rights reserved.

Green reduction of graphene oxide by ascorbic acid

NASA Astrophysics Data System (ADS)

Khosroshahi, Zahra; Kharaziha, Mahshid; Karimzadeh, Fathallah; Allafchian, Alireza

2018-01-01

Graphene, a single layer of sp2-hybridized carbon atoms in a hexagonal (two-dimensional honey-comb) lattice, has attracted strong scientific and technological interest due to its novel and excellent optical, chemical, electrical, mechanical and thermal properties. The solution-processable chemical reduction of Graphene oxide (GO is considered as the most favorable method regarding mass production of graphene. Generally, the reduction of GO is carried out by chemical approaches using different reductants such as hydrazine and sodium borohydride. These components are corrosive, combustible and highly toxic which may be dangerous for personnel health and the environment. Hence, these reducing agents are not promising choice for reducing of graphene oxide (GO). As a consequence, it is necessary for further development and optimization of eco-friendly, natural reducing agent for clean and effective reduction of GO. Ascorbic acid, an eco-friendly and natural reducing agents, having a mild reductive ability and nontoxic property. So, the aim of this research was to green synthesis of GO with ascorbic acid. For this purpose, the required amount of NaOH and ascorbic acid were added to GO solution (0.5 mg/ml) and were heated at 95 °C for 1 hour. According to the X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and electrochemical results, GO were reduced with ascorbic acid like hydrazine with better electrochemical properties and ascorbic acid is an ideal substitute for hydrazine in the reduction of graphene oxide process.

A rationale on the role of intermediate Au(III)-vitamin C complexation in the production of gold nanoparticles

NASA Astrophysics Data System (ADS)

Zümreoglu-Karan, B.

2009-07-01

Preparation of gold nanoparticles, particularly gold nanorods, by wet chemistry processes involves gold seeds, an Au(III) salt, structure directing surfactants, and metal ion additives in the growth solution into which a weak reducing agent is added. The most commonly employed weak reducing agent is l-ascorbic acid (vitamin C) which is known to reduce many metal ions in the solution phase and form complexes with relatively low stability constants. A purple-gray gold-ascorbate compound, obtained from the reaction of sodium tetrachloroaurate(III) with sodium ascorbate, is now reported. The compound possesses the expected structural features of vitamin C-metal complexes as verified by its 13C CP-MAS NMR spectrum. A discussion is also presented on the possibility of gold-ascorbate complexation operating in gold nanoparticle formation.

Fractional CO₂ Laser Pretreatment Facilitates Transdermal Delivery of Two Vitamin C Derivatives.

PubMed

Hsiao, Chien-Yu; Sung, Hsin-Ching; Hu, Sindy; Huang, Yau-Li; Huang, Chun-Hsun

2016-11-16

Topical vitamin C derivatives have been used to treat melasma and used as a skin whitener. The aim of this study was to compare skin histology and permeation of l-ascorbic acid 2-phosphate sesquimagnesium salt (MAP-1) and magnesium l-ascorbic acid-2-phosphate (MAP-2) after fractional CO₂ laser pretreatment. The effect of fractional laser treatment on porcine skin was examined by scanning electron microscopy and confocal laser scanning electron microscopy. The effect of fractional CO₂ laser treatment of different fluencies and pass numbers on transdermal flux of the two vitamin C derivatives through porcine skin was examined in vitro using a Franz diffusion chamber. Fluxes of MAP-1 and MAP-2 across fractional CO₂ laser-treated (5 W) skin were eight- to 13-fold, and 20- to 22-fold higher, respectively, than the fluxes of these compounds across intact skin. Fluxes of MAP-1 and MAP-2 across fractional CO₂ laser-treated (9 W) skin were 14- to 19-fold, and 30- to 42-fold higher, respectively, than their fluxes across intact skin. Fractional CO₂ laser treatment is an effective way of delivering vitamin C derivatives into the skin.

Role of ascorbic acid in the inhibition of polyphenol oxidase and the prevention of browning in different browning-sensitive Lactuca sativa var. capitata (L.) and Eruca sativa (Mill.) stored as fresh-cut produce.

PubMed

Landi, Marco; Degl'Innocenti, Elena; Guglielminetti, Lorenzo; Guidi, Lucia

2013-06-01

Polyphenol oxidase (PPO) and, to a minor extent, peroxidase (POD) represent the key enzymes involved in enzymatic browning, a negative process induced by cutting fresh-cut produce such as lettuce (Lactuca sativa) and rocket salad (Eruca sativa). Although ascorbic acid is frequently utilised as an anti-browning agent, its mechanism in the prevention of the browning phenomenon is not clearly understood. The activity of PPO and POD and their isoforms in lettuce (a high-browning and low-ascorbic acid species) and rocket salad (a low-browning and high-ascorbic species) was characterised. The kinetic parameters of PPO and in vitro ascorbic acid-PPO inhibition were also investigated. In rocket salad, PPO activity was much lower than that in lettuce and cutting induced an increase in PPO activity only in lettuce. Exogenous ascorbic acid (5 mmol L(-1)) reduced PPO activity by about 90% in lettuce. POD did not appear to be closely related to browning in lettuce. PPO is the main enzyme involved in the browning phenomenon; POD appears to play a minor role. The concentration of endogenous ascorbic acid in rocket salad was related to its low-browning sensitivity after cutting. In lettuce, the addition of ascorbic acid directly inhibited PPO activity. The results suggest that the high ascorbic acid content found in rocket salad plays an effective role in reducing PPO activity. © 2012 Society of Chemical Industry.

Salivary ascorbic acid levels in betel quid chewers: A biochemical study.

PubMed

Shetty, Shishir R; Babu, Subhas; Kumari, Suchetha; Prasad, Rajendra; Bhat, Supriya; Fazil, K A

2013-07-01

Quid chewing practice has been a part of our tradition since centuries with little known evidence of oral cancer. However, recent trends show a rise in occurrence of oral cancer often associated with tobacco and arecanut usage. Ascorbic acid is an important salivary antioxidant. Betel leaf which is used in quid is known to contain ascorbic acid. The aim of our study was to assess the salivary levels of ascorbic acid in traditional quid chewers so as to determine whether the betel leaf has protective antioxidant action. Salivary ascorbic acid levels of 60 subjects were estimated using the Dinitrophenyl hydrazine method. The results revealed that quid chewers who used betel leaf had higher salivary ascorbic acid content compared to nonbetel leaf quid chewers. This could possibly be due to the protective antioxidants in the betel leaf.

Effects of ascorbate on leucocytes: Part II. Effects of ascorbic acid and calcium and sodium ascorbate on neutrophil phagocytosis and post-phagocytic metabolic activity.

PubMed

Anderson, R

1979-09-01

The effects of ascorbic acid and calcium and sodium ascorbate at a concentration range of 10(-6)M - 10(-1)M on polymorphonuclear leucocyte (PMN) phagocytosis of Candida albicans and post-phagocytic nitroblue tetrazolium (NBT) reduction, hexose monophosphate shunt (HMS) activity and myeloperoxidase-mediated iodination of ingested protein were investigated. Phagocytosis of C. albicans was unaffected by ascorbate concentrations of 10(-6)M - 10(-2)M; however, progressive inhibition was observed at concentrations of 10(-2)M upwards. Enhancement of resting and stimulated HMS activity and NBT reduction was evident at ascorbate concentrations of 10(-5) M - 10(-2)M. The stimulations of HMS activity and NBT reduction was independent of myeloperoxidase iodination of ingested protein and this latter function was strongly inhibited by ascorbate. Concentrations of ascorbic acid and calcium and sodium ascorbate which caused inhibition of phagocytosis and HMS activity were the same as those which mediated stimulation of cell motility, indicating that independent cellular mechanisms may govern motility and phagocytosis.

Changes in the Ascorbate System during Seed Development of Vicia faba L. 1

PubMed Central

Arrigoni, Oreste; De Gara, Laura; Tommasi, Franca; Liso, Rosalia

1992-01-01

Large changes occur in the ascorbate system during the development of Vicia faba seed and these appear closely related to what are generally considered to be the three stages of embryogenesis. During the first stage, characterized by embryonic cells with high mitotic activity, the ascorbic acid/dehydroascorbic acid ratio is about 7, whereas in the following stage, characterized by rapid cell elongation (stage 2), it is lower than 1. The different ascorbic/dehydroascorbic ratio may be correlated with the level of ascorbate free radical reductase activity, which is high in stage 1 and lower in stage 2. Ascorbate peroxidase activity is high and remains constant throughout stages 1 and 2, but it decreases when the water content of the seed begins to decline (stage 3). In the dry seed, the enzyme disappears together with ascorbic acid. Ascorbate peroxidase activity is observed to be 10 times higher than that of catalase, suggesting that ascorbate peroxidase, rather than catalase, is utilized in scavenging the H2O2 produced in the cell metabolism. There is no ascorbate oxidase in the seed of V. faba. V. faba seeds acquire the capability to synthesize ascorbic acid only after 30 days from anthesis, i.e. shortly before the onset of seed desiccation. This suggests that (a) the young seed is furnished with ascorbic acid by the parent plant throughout the period of intense growth, and (b) it is necessary for the seed to be endowed with the ascorbic acid biosynthetic system before entering the resting state so that the seed can promptly synthesize the ascorbic acid needed to reestablish metabolic activity when germination starts. PMID:16668855

Overexpression of an alfalfa GDP-mannose 3, 5-epimerase gene enhances acid, drought and salt tolerance in transgenic Arabidopsis by increasing ascorbate accumulation.

PubMed

Ma, Lichao; Wang, Yanrong; Liu, Wenxian; Liu, Zhipeng

2014-11-01

GDP-mannose 3', 5'-epimerase (GME) catalyses the conversion of GDP-D-mannose to GDP-L-galactose, an important step in the ascorbic acid (ascorbic acid) biosynthetic pathway in higher plants. In this study, a novel cDNA fragment (MsGME) encoding a GME protein was isolated and characterised from alfalfa (Medicago sativa). An expression analysis confirmed that MsGME expression was induced by salinity, PEG and acidity stresses. MsGME overexpression in Arabidopsis enhanced tolerance of the transgenic plants to salt, drought and acid. Real-time PCR analysis revealed that the transcript levels of GDP-D-mannose pyrophosphorylase (GMP), L-galactose-phosphate 1-P phosphatase (GP) and GDP-L-galactose phosphorylase (GGP) were increased in transgenic Arabidopsis (T3 generation). Moreover, the ascorbate content was increased in transgenic Arabidopsis. Our results suggest that MsGME can effectively enhance tolerance of transgenic Arabidopsis to acid, drought and salt by increasing ascorbate accumulation.

Effect of dietary vitamin C on the growth performance and innate immunity of juvenile cobia (Rachycentron canadum).

PubMed

Zhou, Qicun; Wang, Ligai; Wang, Hualang; Xie, Fengjun; Wang, Tuo

2012-06-01

This study was conducted to evaluate the effects of dietary vitamin C on growth performance, hematologic parameters and innate immune responses in juvenile cobia, Rachycentron canadum. Seven practical diets were formulated to contain 0.0 (as the basal diet), 13.6, 27.2, 54.4, 96.6, 193.4 and 386.5 mg ascorbic acid equivalent kg(-1) diet. Each diet was fed to triplicate groups of juvenile cobia with initial body weight of 5.5 g in 500-L cylindrical fiberglass tank. The results of 8 weeks feeding trial showed that typical vitamin C-deficient signs such as spinal deformation and body nigrescence were observed in the fish fed the basal diet. Fish fed the basal diet had significantly lower weight gain, specific growth rate (SGR), protein efficiency ratio (PER) and feed efficiency (FE) than those fed the diets supplemented with vitamin C, but no significant differences were observed among diets supplemented with vitamin C. However, survival rate was significantly affected by the dietary vitamin C levels, fish fed the basal diet had lower survival rate than those fed the diets supplemented with vitamin C. The ascorbic acid concentration in liver was correlated positively with the dietary vitamin C levels, however, the thiobarbituric acid reactive substances (TBARS) concentrations in liver was not significantly affected by the dietary vitamin C levels, although, fish fed the basal diet had the highest TBARS values among all treatments. The activities of serum lysozyme, superoxide dismutase (SOD), alkaline phophatase (AKP) and total immunoglobulin (Ig) were significantly influenced by the dietary vitamin C levels, fish fed the basal diet had lower lysozyme, SOD, AKP and total Ig than those fed diets supplemented with vitamin C. The serum glucose and triglyceride concentrations were significantly affected by the dietary vitamin C levels. Fish fed the basal diet had lower red blood cell and hemoglobin values than those fed the vitamin C supplemented diets. The challenge

Effects of ascorbic acid and α-tocopherol on the therapeutic index of amphotericin B.

PubMed

Belhachemi, M H; Boucherit, K; Boucherit-Otmani, Z; Belmir, S; Benbekhti, Z

2014-12-01

Amphotericin B (AmB) remains the antifungal polyene of choice in deep fungal infections, but its high toxicity to mammalian cells limits its use. This toxicity is partly due to lipid peroxidation exerted by amphotericin B in cell membranes. The work we have undertaken focused on the one part the evaluation of the efficacy of amphotericin B in the presence of some antioxidants vitamins (vitamin C "ascorbic acid" and vitamin E "α-tocopherol") against the yeast Candida albicans ATCC 10231. Secondly, we have tested the cytotoxicity of these formulations on human red blood cells. The results showed a significant improvement in the efficiency of our formulations tested from 7% to 12% compared with amphotericin B alone at therapeutic concentrations. Furthermore, the addition of vitamin C and vitamin E protects human red blood cells against the cytotoxicity induced by amphotericin B with 17%. This is due may be to the antioxidant power of vitamins which confer protection against the autoxidation of the molecule of amphotericin B. On the other hand, it is noticed that the yeast regrows after 24h whatever in complex with vitamin C or vitamin E of the stock solution. On completion of this study, the incorporation of antioxidant vitamins that we propose to the reaction medium of antifungal improved the therapeutic index of amphotericin B. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Therapeutic review: is ascorbic acid of value in chromium poisoning and chromium dermatitis?

PubMed

Bradberry, S M; Vale, J A

1999-01-01

Repeated topical exposure to chromium(VI) may cause an allergic contact dermatitis or the formation of chrome ulcers. Systemic toxicity may occur following the ingestion of a chromium(VI) salt, from chromium(VI)-induced skin burns, or from inhalation of chromium(VI) occurring occupationally. Soluble chromium(VI) salts are usually absorbed more easily and cross cell membranes more readily than trivalent chromium salts, and, therefore chromium(VI) is more toxic than chromium(III). In experimental studies, endogenous ascorbic acid in rat lung, liver, and kidney and human plasma, effectively reduces chromium(VI) to chromium(III). The administration of exogenous ascorbic acid has been advocated therefore in the treatment of systemic chromium poisoning and chromium dermatitis to enhance the extracellular reduction of chromium(VI) to the less bioavailable chromium(III). In vitro experiments confirm that the addition of ascorbic acid to plasma containing chromium(VI) leads to a dose-dependent reduction of chromium(VI) to chromium(III). In animal studies, parenteral ascorbic acid 0.5-5 g/kg significantly reduced chromium-induced nephrotoxicity when administered 30 minutes before parenteral sodium dichromate and up to 1 hour after parenteral sodium chromate dosing. Parenteral ascorbic acid 0.5-5 g/kg also reduced mortality when given orally up to 2 hours after oral potassium dichromate dosing. However, the administration of parenteral ascorbic acid more than 2 hours after parenteral chromate in these experimental studies did not protect against renal damage, and parenteral ascorbic acid given 3 hours postparenteral chromate increased toxicity. In addition, there is no confirmed clinical evidence that the administration of ascorbic acid lessens morbidity or mortality in systemic chromium poisoning. A possible reason for the lack of benefit of ascorbic acid when administration is delayed, is that chromium(VI) cellular uptake has occurred prior to ascorbic acid administration

The Effect of Copper And Zinc Nanoparticles on the Growth Parameters, Contents of Ascorbic Acid, and Qualitative Composition of Amino Acids and Acylcarnitines in Pistia stratiotes L. (Araceae)

NASA Astrophysics Data System (ADS)

Olkhovych, Olga; Volkogon, Mykola; Taran, Nataliya; Batsmanova, Lyudmyla; Kravchenko, Inna

2016-04-01

The paper covers the research of copper and zinc nanoparticle effect on the content of ascorbic acid, and quantitative and qualitative composition of amino acids and acylcarnitines in Pistia stratiotes L. plants. Plant exposition to copper nanoparticles led to the decrease in (1) the amount of ascorbic acid, (2) the total content of amino acids (by 25 %), and (3) the amount of all studied amino acids except for the glycine amino acid. At this, the amount of 5-oxoproline, arginine, leucine, ornithine, phenylalanine, proline, serine, and tyrosine was two times lower than in control plants. The reduction of the contents of 8 out of 12 investigated acylcarnitines (namely C0, C2, C3, C5, C6, C8, C16, C18:1) was observed in plants under the influence of copper nanoparticles. The result of plants incubation with zinc nanoparticles was the decrease in (1) the amount of ascorbic acid, (2) the total content of amino acids (by 15 %), (3) the content of leucine, methionine, phenylalanine, proline, and tyrosine (more than twice), and (4) the content of 10 acylcarnitines (C0, C2, C3, C4, C5, C10, C16, C18, C18:1, C18:2). The observed reduction in amino acid contents may negatively affect plants adaptive reactions associated with de novo synthesis of stress proteins. At the same time, the decrease in the content of acylcarnitines, responsible for fatty acid transportation, may lead to the changes in the activity and direction of lipid metabolism in plants and reduce plant's ability to use free fatty acids as the oxidation substrate for cell reparation.

Vitamin C in human health and disease is still a mystery ? An overview

PubMed Central

Naidu, K Akhilender

2003-01-01

Ascorbic acid is one of the important water soluble vitamins. It is essential for collagen, carnitine and neurotransmitters biosynthesis. Most plants and animals synthesize ascorbic acid for their own requirement. However, apes and humans can not synthesize ascorbic acid due to lack of an enzyme gulonolactone oxidase. Hence, ascorbic acid has to be supplemented mainly through fruits, vegetables and tablets. The current US recommended daily allowance (RDA) for ascorbic acid ranges between 100–120 mg/per day for adults. Many health benefits have been attributed to ascorbic acid such as antioxidant, anti-atherogenic, anti-carcinogenic, immunomodulator and prevents cold etc. However, lately the health benefits of ascorbic acid has been the subject of debate and controversies viz., Danger of mega doses of ascorbic acid? Does ascorbic acid act as a antioxidant or pro-oxidant ? Does ascorbic acid cause cancer or may interfere with cancer therapy? However, the Panel on dietary antioxidants and related compounds stated that the in vivo data do not clearly show a relationship between excess ascorbic acid intake and kidney stone formation, pro-oxidant effects, excess iron absorption. A number of clinical and epidemiological studies on anti-carcinogenic effects of ascorbic acid in humans did not show any conclusive beneficial effects on various types of cancer except gastric cancer. Recently, a few derivatives of ascorbic acid were tested on cancer cells, among them ascorbic acid esters showed promising anticancer activity compared to ascorbic acid. Ascorbyl stearate was found to inhibit proliferation of human cancer cells by interfering with cell cycle progression, induced apoptosis by modulation of signal transduction pathways. However, more mechanistic and human in vivo studies are needed to understand and elucidate the molecular mechanism underlying the anti-carcinogenic property of ascorbic acid. Thus, though ascorbic acid was discovered in 17th century, the exact role

Salivary ascorbic acid levels in betel quid chewers: A biochemical study

PubMed Central

Shetty, Shishir R.; Babu, Subhas; Kumari, Suchetha; Prasad, Rajendra; Bhat, Supriya; Fazil, K. A.

2013-01-01

Background: Quid chewing practice has been a part of our tradition since centuries with little known evidence of oral cancer. However, recent trends show a rise in occurrence of oral cancer often associated with tobacco and arecanut usage. Ascorbic acid is an important salivary antioxidant. Betel leaf which is used in quid is known to contain ascorbic acid. Aim: The aim of our study was to assess the salivary levels of ascorbic acid in traditional quid chewers so as to determine whether the betel leaf has protective antioxidant action. Materials and Methods: Salivary ascorbic acid levels of 60 subjects were estimated using the Dinitrophenyl hydrazine method. Results: The results revealed that quid chewers who used betel leaf had higher salivary ascorbic acid content compared to nonbetel leaf quid chewers. This could possibly be due to the protective antioxidants in the betel leaf. PMID:24455594

Ascorbic acid deficiency aggravates stress-induced gastric mucosal lesions in genetically scorbutic ODS rats.

PubMed

Ohta, Y; Chiba, S; Imai, Y; Kamiya, Y; Arisawa, T; Kitagawa, A

2006-12-01

We examined whether ascorbic acid (AA) deficiency aggravates water immersion restraint stress (WIRS)-induced gastric mucosal lesions in genetically scorbutic ODS rats. ODS rats received scorbutic diet with either distilled water containing AA (1 g/l) or distilled water for 2 weeks. AA-deficient rats had 12% of gastric mucosal AA content in AA-sufficient rats. AA-deficient rats showed more severe gastric mucosal lesions than AA-sufficient rats at 1, 3 or 6 h after the onset of WIRS, although AA-deficient rats had a slight decrease in gastric mucosal AA content, while AA-sufficient rats had a large decrease in that content. AA-deficient rats had more decreased gastric mucosal nonprotein SH and vitamin E contents and increased gastric mucosal lipid peroxide content than AA-sufficient rats at 1, 3 or 6 h of WIRS. These results indicate that AA deficiency aggravates WIRS-induced gastric mucosal lesions in ODS rats by enhancing oxidative damage in the gastric mucosa.

[Natural or synthetic vitamin C? A new substance's precarious status behind the scenes of World War II].

PubMed

Bächi, Beat

2008-01-01

Today, thousands of tons of vitamin C (l-ascorbic acid) is synthesized every year by the pharmaceutical industry. Synthetically produced vitamin C is widely accepted as having the same physiological effects as vitamin C isolated from natural sources. This is an important difference compared to the 1930s when vitamin C was synthesized for the first time. The identity of synthetic vitamin C with natural vitamin C had to be established. First of all, the scientific community had to accept that artificial I-ascorbic acid and natural vitamin C were chemically identical and had the same physiological effects. Second, other communities like food manufacturers, military health officials, and the broader public also had to be persuaded that these substances were equal. This article demonstrates how Hoffmann-La Roche, a Swiss pharmaceutical company and world-leading producer of synthetic vitamins in the 20th century, tried to coax its adversaries into supporting artificial vitamin C. In doing so, synthetic vitamin C was naturalized in different ways. In the case of Switzerland during the Second World War era, the mentality of national defense and the quest for products supporting autarchy helped to convince perspective consumers. Thus in order to sell a new chemical substance, cultural meaning had to be attached to it.

Ascorbic acid and tannins from Emblica officinalis Gaertn. Fruits--a revisit.

PubMed

Majeed, Muhammed; Bhat, Beena; Jadhav, Atul N; Srivastava, Jyotish S; Nagabhushanam, Kalyanam

2009-01-14

The fruits of Emblica officinalis Gaertn. (Euphorbiaceae), also known as amla in Ayurveda, are considered to be a rich source of ascorbic acid. However, the antioxidant activities exhibited by E. officinalis extract are superior to those of ascorbic acid itself. Low molecular hydrolyzable tannins emblicanins A and B have been suggested in the earlier literature to be the contributory antioxidant molecules in the extract. This work finds no evidence for the presence of emblicanins A and B in the extract. In addition, the high content of ascorbic acid is also questionable due to previous nonidentification of coeluting mucic acid gallates. This paper reports a new HPLC method to detect even trace amounts of ascorbic acid in E. officinalis fruit juice or extract.

Effect of docosahexaenoic acid and ascorbate on peroxidation of retinal membranes of ODS rats.

PubMed

Wang, Jin-Ye; Sekine, Seiji; Saito, Morio

2003-04-01

Mutant male osteogenic disorder Shionogi (ODS) rats, unable to synthesize ascorbic acid, were fed diets containing a high content of docosahexaenoic acid (DHA) and different amounts of ascorbic acid, to study the effect of DHA on peroxidative susceptibility of the retina and possible antioxidant action of ascorbic acid. ODS rats were fed from 7 weeks of age with diets containing high DHA (6.4% of total energy). A control group received a diet high in linoleic acid. The diets also contained varying amounts of ascorbic acid. Fatty acid compositions and phospholipid hydroperoxides in rod outer segment (ROS) membranes, and retinal ascorbic acid were analyzed. DHA in ROS membranes was significantly increased in rats fed high DHA, compared with the linoleic acid diet. Levels of phospholipid hydroperoxides in the DHA-fed rats were significantly higher than the linoleic acid-fed rats. Ascorbic acid supplementation did not suppress the phospholipid hydroperoxide levels after a high DHA diet, even when the supplement increased the content of retinal ascorbic acid. In conclusion, high DHA feeding induced a marked increase of phospholipid hydroperoxides in ROS membranes of ODS rats. Supplementation of ascorbic acid did not reverse this increase.

Ascorbic Acid Determination in Commercial Fruit Juice Samples by Cyclic Voltammetry

PubMed Central

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

Preparation of a solid-in-oil nanosuspension containing L-ascorbic acid as a novel long-term stable topical formulation.

PubMed

Piao, Hongyu; Kamiya, Noriho; Cui, Fude; Goto, Masahiro

2011-11-25

L-Ascorbic acid (AA, vitamin C) easily decomposes into inactive compounds in aqueous solutions and this has limited its topical use. This work reports the preparation of a solid-in-oil nanosuspension (SONS) containing AA and validation of its basic storage stability. Although AA itself is water-soluble, it can readily be nanosuspended in squalane via complex formation involving a combination of sucrose erucate (i.e. lipophilic surfactant) and sucrose monolaureate (i.e. hydrophilic surfactant) to yield SONS with a very low moisture content (<500 ppm). To extract encapsulated AA, a lipase-based enzymatic degradation technique was used to degrade a formulation phase making it easier for AA to distribute into an extraction solution. Our results demonstrate that almost all the encapsulated AA (95.3%) was readily extracted from the SONS upon addition of medium-chain triglyceride, which offers the possibility of degrading the formulation phase using lipase. Finally, its storage stability study was investigated at 25°C over 90 days under protection from light. An aqueous solution containing AA was used as a control. Compared with the control, the SONS markedly increased the stability of AA due to its low moisture content and, thus, the potential usefulness SONSs as a novel long-term stable topical formulation of AA has been proved. Copyright © 2011 Elsevier B.V. All rights reserved.

Effect of ascorbic acid on prevention of hypercholesterolemia induced atherosclerosis.

PubMed

Das, S; Ray, R; Snehlata; Das, N; Srivastava, L M

2006-04-01

The notion that oxidation of lipids and propagation of free radicals may contribute to the pathogenesis of atherosclerosis is supported by a large body of evidence. To circumvent the damage caused by oxygen free radicals, antioxidants are needed which provide the much needed neutralization of free radical by allowing the pairing of electrons. In this study we have investigated the effect of ascorbic acid, a water soluble antioxidant on the development of hypercholesterolemia induced atherosclerosis in rabbits. Rabbits were made hypercholesterolemic and atherosclerotic by feeding 100 mg cholesterol/day. Different doses of ascorbic acid were administered to these rabbits. Low dose of ascorbic acid (0.5 mg/100 g body weight/day) did not have any significant effect on the percent of total area covered by atherosclerotic plaque. However, ascorbic acid when fed at a higher dose (15 mg/100 g body weight/day) was highly effective in reducing the atherogenecity. With this dose the percent of total surface area covered by atherosclerotic plaque was significantly less (p < 0.001). This suggests that use of ascorbic acid may have great promise in the prevention of hypercholesterolemia induced atherosclerosis.

Salivary pH while dissolving vitamin C-containing tablets.

PubMed

Hays, G L; Bullock, Q; Lazzari, E P; Puente, E S

1992-10-01

Vitamin C is packaged in numerous forms which allow protracted exposure of the teeth to ascorbic acid. The repeated use of chewable mega dose tablets of vitamin C as a mint can damage the teeth by dissolving the enamel. In the time it takes to dissolve a chewable vitamin C tablet, a salivary pH drop takes place; salivary calcium and phosphorus ion concentration drops, and enamel dissolution may begin. Although sodium ascorbate, a buffering agent, is present in many vitamin C products, it may be added in insufficient quantity to be effective. With no apparent therapeutic value from topical vitamin C, vitamin C-containing products should be swallowed.

Transcriptomic analysis of genes involved in the biosynthesis, recycling and degradation of L-ascorbic acid in pepper fruits (Capsicum annuum L.).

PubMed

Alós, Enriqueta; Rodrigo, María J; Zacarías, Lorenzo

2013-06-01

Sweet pepper (Capsicum annuum L.) is widely recognized among the vegetables with high content of ascorbic acid (AsA). However, the metabolic pathways involved in the biosynthesis, recycling and degradation of AsA and their relative contribution to the concentration of AsA have not been established yet. In the present work, the expression levels of selected genes involved in the AsA biosynthesis, degradation and recycling pathways were analyzed during development and ripening of pepper fruit cv. Palermo and in mature fruit of four cultivars (Lipari, C-116, Surrentino and Italverde) with different AsA concentrations. An inverse correlation was found between the expression of the biosynthetic genes and AsA concentrations, which could indicate that a feedback mechanism regulates AsA homeostasis in pepper fruits. Interestingly, analysis of mRNA levels of ascorbate oxidase, involved in the degradation of AsA, suggests that this enzyme plays a critical role in the regulation of the AsA pool during fruit development and ripening. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Effect of ascorbic acid on storage of Greyhound erythrocytes.

PubMed

Fontes, Jorge A; Banerjee, Uddyalok; Iazbik, M Cristina; Marín, Liliana M; Couto, C Guillermo; Palmer, Andre F

2015-09-01

To assess changes in biochemical and biophysical properties of canine RBCs during cold (1° to 6°C) storage in a licensed RBC additive solution (the RBC preservation solution designated AS-1) supplemented with ascorbic acid. Blood samples from 7 neutered male Greyhounds; all dogs had negative results when tested for dog erythrocyte antigen 1.1. Blood was collected into citrate-phosphate-dextrose and stored in AS-1. Stored RBCs were supplemented with 7.1mM ascorbic acid or with saline (0.9% NaCl) solution (control samples). Several biochemical and biophysical properties of RBCs were measured, including percentage hemolysis, oxygen-hemoglobin equilibrium, and the kinetic rate constants for O2 dissociation, carbon monoxide association, and nitric oxide dioxygenation. Greyhound RBCs stored in AS-1 supplemented with ascorbic acid did not have significantly decreased hemolysis, compared with results for the control samples, during the storage period. In this study, ascorbic acid did not reduce hemolysis during storage. Several changes in stored canine RBCs were identified as part of the hypothermic storage lesion.

Inhibition of Human Amylin Aggregation and Cellular Toxicity by Lipoic Acid and Ascorbic Acid.

PubMed

Azzam, Sarah Kassem; Jang, Hyunwoo; Choi, Myung Chul; Alsafar, Habiba; Lukman, Suryani; Lee, Sungmun

2018-04-30

More than 30 human degenerative diseases result from protein aggregation such as Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM). Islet amyloid deposits, a hallmark in T2DM, are found in pancreatic islets of more than 90 % of T2DM patients. An association between amylin aggregation and reduction in β-cell mass was also established by post-mortem studies. A strategy in preventing protein aggregation-related disorders is to inhibit the protein aggregation and associated toxicity. In this study we demonstrated that two inhibitors, lipoic acid and ascorbic acid, significantly inhibited amylin aggregation. Compared to amylin (15 μM) as 100 %, lipoic acid and ascorbic acid reduced amylin fibril formation to 42.1 ± 17.2 % and 42.9 ± 12.8 % respectively, which is confirmed by fluorescence and TEM images. In cell viability tests, both inhibitors protected RIN-m5f β-cells from the toxicity of amylin aggregates. At 10:1 molar ratio of lipoic acid to amylin, lipoic acid with amylin increased the cell viability to 70.3 %, whereas only 42.8 % RIN-m5f β-cells survived in amylin aggregates. For ascorbic acid, an equimolar ratio achieved the highest cell viability of 63.3 % as compared to 42.8 % with amylin aggregates only. Docking results showed that lipoic acid and ascorbic acid physically interact with amylin amyloidogenic region (residues Ser20-Ser29) via hydrophobic interactions; hence reducing aggregation levels. Therefore, lipoic acid and ascorbic acid prevented amylin aggregation via hydrophobic interactions, which resulted in the prevention of cell toxicity in vitro.

Two genes in Arabidopsis thaliana encoding GDP-L-galactose phosphorylase are required for ascorbate biosynthesis and seedling viability.

PubMed

Dowdle, John; Ishikawa, Takahiro; Gatzek, Stephan; Rolinski, Susanne; Smirnoff, Nicholas

2007-11-01

Plants synthesize ascorbate from guanosine diphosphate (GDP)-mannose via L-galactose/L-gulose, although uronic acids have also been proposed as precursors. Genes encoding all the enzymes of the GDP-mannose pathway have previously been identified, with the exception of the step that converts GDP-L-galactose to L-galactose 1-P. We show that a GDP-L-galactose phosphorylase, encoded by the Arabidopsis thaliana VTC2 gene, catalyses this step in the ascorbate biosynthetic pathway. Furthermore, a homologue of VTC2, At5g55120, encodes a second GDP-L-galactose phosphorylase with similar properties to VTC2. Two At5g55120 T-DNA insertion mutants (vtc5-1 and vtc5-2) have 80% of the wild-type ascorbate level. Double mutants were produced by crossing the loss-of-function vtc2-1 mutant with each of the two vtc5 alleles. These show growth arrest immediately upon germination and the cotyledons subsequently bleach. Normal growth was restored by supplementation with ascorbate or L-galactose, indicating that both enzymes are necessary for ascorbate generation. vtc2-1 leaves contain more mannose 6-P than wild-type. We conclude that the GDP-mannose pathway is the only significant source of ascorbate in A. thaliana seedlings, and that ascorbate is essential for seedling growth. A. thaliana leaves accumulate more ascorbate after acclimatization to high light intensity. VTC2 expression and GDP-L-galactose phosphorylase activity rapidly increase on transfer to high light, but the activity of other enzymes in the GDP-mannose pathway is little affected. VTC2 and At5g55120 (VTC5) expression also peak in at the beginning of the light cycle and are controlled by the circadian clock. The GDP-L-galactose phosphorylase step may therefore play an important role in controlling ascorbate biosynthesis.

Beyond the antioxidant: the double life of vitamin C.

PubMed

De Tullio, Mario C

2012-01-01

. 159-172). All this has very little to do with the celebrated role of ascorbic acid (ASC) as an antioxidant. So, if the fate of ASC had to be found in its name, its role in the prevention of scurvy (i.e. beyond the antioxidant function) should be considered its main feature. But, in spite of more than 80 years of extensive research (34,424 hits in a PubMed query on January 6 2007), an unprecedented popularity among the general public, an estimated market of several billion dollars (Hancock RD, Viola R (2005) Improving the nutritional value of crops through enhancement of l-ascorbic acid (vitamin C) content: Rationale and biotechnological opportunities. J Agr Food Chem 53:5248-5257), we should honestly conclude that the fate of vitamin C is still in the first name it received, many years ago: we still ignore much of its actual relevance in cell metabolism, although we are progressively getting aware of the many facets of this fascinating molecule, and its direct involvement in the regulation of apparently unrelated pathways (Arrigoni O, De Tullio MC (2002) Ascorbic acid, much more than just an antioxidant. Biochim Biophys Acta 1569:1-9; De Tullio MC, Arrigoni O (2004) Hopes, disillusions and more hopes from vitamin C. Cell Mol Life Sci 61:209-219; Duarte TL, Lunec J (2005) When is an antioxidant not an antioxidant? A review of novel actions and reactions of vitamin C. Free Rad Res 39:671-686). Recent data on ASC involvement in cell signalling and gene expression open new perspectives, that will be presented and discussed in this chapter.

Myths, Artifacts, and Fatal Flaws: Identifying Limitations and Opportunities in Vitamin C Research

PubMed Central

Michels, Alexander J.; Frei, Balz

2013-01-01

Research progress to understand the role of vitamin C (ascorbic acid) in human health has been slow in coming. This is predominantly the result of several flawed approaches to study design, often lacking a full appreciation of the redox chemistry and biology of ascorbic acid. In this review, we summarize our knowledge surrounding the limitations of common approaches used in vitamin C research. In human cell culture, the primary issues are the high oxygen environment, presence of redox-active transition metal ions in culture media, and the use of immortalized cell lines grown in the absence of supplemental ascorbic acid. Studies in animal models are also limited due to the presence of endogenous ascorbic acid synthesis. Despite the use of genetically altered rodent strains lacking synthesis capacity, there are additional concerns that these models do not adequately recapitulate the effects of vitamin C deprivation and supplementation observed in humans. Lastly, several flaws in study design endemic to randomized controlled trials and other human studies greatly limit their conclusions and impact. There also is anecdotal evidence of positive and negative health effects of vitamin C that are widely accepted but have not been substantiated. Only with careful attention to study design and experimental detail can we further our understanding of the possible roles of vitamin C in promoting human health and preventing or treating disease. PMID:24352093

A highly specific l-galactose-1-phosphate phosphatase on the path to ascorbate biosynthesis

PubMed Central

Laing, William A.; Bulley, Sean; Wright, Michele; Cooney, Janine; Jensen, Dwayne; Barraclough, Di; MacRae, Elspeth

2004-01-01

Ascorbate is a critical compound in plants and animals. Humans are unable to synthesize ascorbate, and their main source of this essential vitamin are plants. However, the pathway of synthesis in plants is yet to be established, and several unknown enzymes are only postulated to exist. We describe a specific l-galactose-1-phosphate (l-gal-1-P) phosphatase that we partially purified from young kiwifruit (Actinidia deliciosa) berries. The enzyme had a native molecular mass of ≈65 kDa, was completely dependent on Mg2+ for activity and was very specific in its ability to hydrolyze l-gal-1-P. The activity had a pH optimum of 7.0, a KM(l-gal-1-P) of 20–40 μM and a Ka(Mg2+) of 0.2 mM. The activity was inhibited by Mg2+ at concentrations >2 mM. The enzyme from Arabidopsis thaliana shoots showed similar properties to the kiwifruit enzyme. The Arabidopsis thaliana enzyme preparation was digested with trypsin, and proteins present were identified by using liquid chromatography–MS. One of 24 proteins present in our preparation was an Arabidopsis thaliana protein, At3g02870, annotated myo-inositol-1-phosphate phosphatase in GenBank, that matched the characteristics of the purified l-gal-1-phosphate phosphatase. We then expressed a kiwifruit homologue of this gene in Escherichia coli and found that it showed 14-fold higher maximum velocity for l-gal-1-P than myo-inositol-1-P. The expressed enzyme showed very similar properties to the enzyme purified from kiwifruit and Arabidopsis, except that its KM(l-gal-1-P) and Ka(Mg2+) were higher in the expressed enzyme. The data are discussed in terms of the pathway to ascorbate biosynthesis in plants PMID:15550539

Chemical stability study of vitamins thiamine, riboflavin, pyridoxine and ascorbic acid in parenteral nutrition for neonatal use

PubMed Central

2011-01-01

Background The objective of this work was to study the vitamins B1, B2, B6 and C stability in a pediatric formulation containing high amounts of calcium in the presence of organic phosphate, amino acids, glucose, sodium chloride, magnesium sulfate, pediatric vitamins and trace elements under different conditions using developed and validated analytical methods. Methods The study was carried out during 72 h with formulations packaged in recommended storage temperature (4°C) and 25°C, with and without photoprotection. Results The results showed that the methodologies used for assessing the chemical stability of vitamins B1, B2, B6 and C in the formulation were selective, linear, precise and accurate. The vitamins could be considered stable in the formulation during the three days of study if stored at 4°C. When stored at 25°C vitamin C presented instability after 48 h. Conclusion The pediatric formulation containing high amount of calcium in the presence of organic phosphate, amino acids, glucose, sodium chloride, magnesium sulphate, pediatric vitamins and trace elements packaged in bag-type trilaminate presented a shelf life of the 72 h, when maintained under refrigeration, between 2°C and 8°C. This shelf life was measured considering the vitamins studied. Further studies are needed including all the vitamins present in this formulation. PMID:21569609

Role of ascorbic acid supplement in amelioration of anaemia in lead intoxication.

PubMed

Farooq, Yasir; Farooq, Muhammad Asif; Hussain, Aamir

2016-09-01

To assess anaemia and oxidative stress in rats that were injected lead and to evaluate the possible effects of ascorbic acid supplementation on these parameters. This randomised control trial study was conducted at the Army Medical College, Rawalpindi, Pakistan, from October 2007 to September 2008, and comprised Sprague Dawley rats. The rats were randomly divided into three groups. The rats in Group 1 were given weekly injections of sodium acetate, and rats of Group 2 and 3 were given weekly injections of lead acetate. Ascorbic acid was supplemented in the drinking water of rats of Group 3. At the end of six weeks, terminal sampling was done and blood obtained was used to assess the serum malondialdehyde levels and red cell parameters. Of the 105 rats, each group had 35(33.33%). The overall mean age was 105±15 days and the mean weight was 225±25gm. The mean malondialdehyde level was 3.2±0.39 µmol /L in Group 1, 7.8±0.48 in Group 2 and 3.8±0.34 in Group 3 (p<0.001). The mean haemoglobin level was 13.16±0.57 g/dL, 10.64±0.86 and 12.22±0.81, respectively (p<0.001). The red blood cells count was 7.63±0.33 106/µL in Group 1, 6.29±0.54 in Group 2 and 6.83±0.45 in Group 3 (p<0.001). Administration of ascorbic acid in drinking water significantly reduced the oxidative stress and anaemia caused by lead intoxication.

Immunomodulatory Role of Ocimum gratissimum and Ascorbic Acid against Nicotine-Induced Murine Peritoneal Macrophages In Vitro

PubMed Central

Mahapatra, Santanu Kar; Chakraborty, Subhankari Prasad; Roy, Somenath

2011-01-01

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. PMID:22220218

The Rheological Properties of Lipid Monolayers Modulate the Incorporation of l-Ascorbic Acid Alkyl Esters.

PubMed

Díaz, Yenisleidy de Las Mercedes Zulueta; Mottola, Milagro; Vico, Raquel V; Wilke, Natalia; Fanani, María Laura

2016-01-19

In this work, we tested the hypothesis that the incorporation of amphiphilic drugs into lipid membranes may be regulated by their rheological properties. For this purpose, two members of the l-ascorbic acid alkyl esters family (ASCn) were selected, ASC16 and ASC14, which have different rheological properties when organized at the air/water interface. They are lipophilic forms of vitamin C used in topical pharmacological preparations. The effect of the phase state of the host lipid membranes on ASCn incorporation was explored using Langmuir monolayers. Films of pure lipids with known phase states have been selected, showing liquid-expanded, liquid-condensed, and solid phases as well as pure cholesterol films in liquid-ordered state. We also tested ternary and quaternary mixed films that mimic the properties of cholesterol containing membranes and of the stratum corneum. The compressibility and shear properties of those monolayers were assessed in order to define its phase character. We found that the length of the acyl chain of the ASCn compounds induces differential changes in the rheological properties of the host membrane and subtly regulates the kinetics and extent of the penetration process. The capacity for ASCn uptake was found to depend on the phase state of the host film. The increase in surface pressure resultant after amphiphile incorporation appears to be a function of the capacity of the host membrane to incorporate such amphiphile as well as the rheological response of the film. Hence, monolayers that show a solid phase state responded with a larger surface pressure increase to the incorporation of a comparable amount of amphiphile than liquid-expanded ones. The cholesterol-containing films, including the mixture that mimics stratum corneum, allowed a very scarce ASCn uptake independently of the membrane diffusional properties. This suggests an important contribution of Cho on the maintenance of the barrier function of stratum corneum.

Treatment of Pancreatic Cancer with Pharmacological Ascorbate

PubMed Central

Cieslak, John A.; Cullen, Joseph J.

2016-01-01

The prognosis for patients diagnosed with pancreatic cancer remains dismal, with less than 3% survival at 5 years. Recent studies have demonstrated that high-dose, intravenous pharmacological ascorbate (ascorbic acid, vitamin C) induces cytotoxicity and oxidative stress selectively in pancreatic cancer cells vs. normal cells, suggesting a promising new role of ascorbate as a therapeutic agent. At physiologic concentrations, ascorbate functions as a reducing agent and antioxidant. However, when pharmacological ascorbate is given intravenously, it is possible to achieve millimolar plasma concentration. At these pharmacological levels, and in the presence of catalytic metal ions, ascorbate can induce oxidative stress through the generation of hydrogen peroxide (H2O2). Recent in vitro and in vivo studies have demonstrated ascorbate oxidation occurs extracellularly, generating H2O2 flux into cells resulting in oxidative stress. Pharmacologic ascorbate also inhibits the growth of pancreatic tumor xenografts and displays synergistic cytotoxic effects when combined with gemcitabine in pancreatic cancer. Phase I trials of pharmacological ascorbate in pancreatic cancer patients have demonstrated safety and potential efficacy. In this chapter, we will review the mechanism of ascorbate-induced cytotoxicity, examine the use of pharmacological ascorbate in treatment and assess the current data supporting its potential as an adjuvant in pancreatic cancer. PMID:26201606

Beta-glycerophosphate accelerates RANKL-induced osteoclast formation in the presence of ascorbic acid.

PubMed

Noh, A Long Sae Mi; Yim, Mijung

2011-03-01

Despite numerous reports of the synergistic effects of beta-glycerophosphate and ascorbic acid in inducing the differentiation of osteoblasts, little is known about their roles in osteoclastic differentiation. Therefore, we investigated the effect of beta-glycerophosphate on osteoclastogenesis in the presence of ascorbic acid using primary mouse bone marrow cultures treated with macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor (NF)-kappaB ligand (RANKL). Beta-Glycerophosphate dose-dependently increased RANKL-induced osteoclast formation in the presence of ascorbic acid. This stimulatory effect was apparent when beta-glycerophosphate and ascorbic acid were only added during the late stages of the culture period, indicating that they influence later events in osteoclastic differentiation. While the combination of beta-glycerophosphate and ascorbic acid inhibited RANKL-stimulated activation of ERK and p38, and degradation of IkappaB, it increased the induction of c-Fos and NFATc1. In addition, beta-glycerophosphate and ascorbic acid together enhanced the induction of COX-2 following RANKL stimulation. Taken together, our data suggest that beta-glycerophosphate and ascorbic acid have synergistic effects on osteoclast formation, increasing RANKL-mediated induction of c-Fos, NFATc1 and COX-2 in osteoclast precursors.

Identification and functional analysis of the L-ascorbate-specific enzyme II complex of the phosphotransferase system in Streptococcus mutans.

PubMed

Wu, Xinyu; Hou, Jin; Chen, Xiaodan; Chen, Xuan; Zhao, Wanghong

2016-03-22

Streptococcus mutans is the primary etiological agent of human dental caries. It can metabolize a wide variety of carbohydrates and produce large amounts of organic acids that cause enamel demineralization. Phosphoenolpyruvate-dependent sugar phosphotransferase system (PTS) plays an important role in carbohydrates uptake of S. mutans. The ptxA and ptxB genes in S. mutans encode putative enzyme IIA and enzyme IIB of the L-ascorbate-specific PTS. The aim of this study was to analyze the function of these proteins and understand the transcriptional regulatory mechanism. ptxA (-), ptxB (-), as well as ptxA (-) , ptxB (-) double-deletion mutants all had more extended lag phase and lower growth yield than wild-type strain UA159 when grown in the medium using L-ascorbate as the sole carbon source. Acid production and acid killing assays showed that the absence of the ptxA and ptxB genes resulted in a reduction in the capacity for acidogenesis, and all three mutant strains did not survive an acid shock. According to biofilm and extracellular polysaccharides (EPS) formation analysis, all the mutant strains formed much less prolific biofilms with small amounts of EPS than wild-type UA159 when using L-ascorbate as the sole carbon source. Moreover, PCR analysis and quantitative real-time PCR revealed that sgaT, ptxA, ptxB, SMU.273, SMU.274 and SMU.275 appear to be parts of the same operon. The transcription levels of these genes were all elevated in the presence of L-ascorbate, and the expression of ptxA gene decreased significantly once ptxB gene was knockout. The ptxA and ptxB genes are involved in the growth, aciduricity, acidogenesis, and formation of biofilms and EPS of S. mutans when L-ascorbate is the sole carbon source. In addition, the expression of ptxA is regulated by ptxB. ptxA, ptxB, and the upstream gene sgaT, the downstream genes SMU.273, SMU.274 and SMU.275 appear to be parts of the same operon, and L-ascorbate is a potential inducer of the operon.

Precision of dehydroascorbic acid quantitation with the use of the subtraction method--validation of HPLC-DAD method for determination of total vitamin C in food.

PubMed

Mazurek, Artur; Jamroz, Jerzy

2015-04-15

In food analysis, a method for determination of vitamin C should enable measuring of total content of ascorbic acid (AA) and dehydroascorbic acid (DHAA) because both chemical forms exhibit biological activity. The aim of the work was to confirm applicability of HPLC-DAD method for analysis of total content of vitamin C (TC) and ascorbic acid in various types of food by determination of validation parameters such as: selectivity, precision, accuracy, linearity and limits of detection and quantitation. The results showed that the method applied for determination of TC and AA was selective, linear and precise. Precision of DHAA determination by the subtraction method was also evaluated. It was revealed that the results of DHAA determination obtained by the subtraction method were not precise which resulted directly from the assumption of this method and the principles of uncertainty propagation. The proposed chromatographic method should be recommended for routine determinations of total vitamin C in various food. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

PubMed

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.

Effect of antioxidant vitamins A, C, E and their analogues on azo-dye binding protein in liver of rats treated with p-dimethylaminoazobenzene.

PubMed

Velanganni, A Antony Joseph; Balasundaram, C

2010-04-01

p-Dimethylaminoazobenzene (DAB) is an azo-dye and known to cause liver tumour in rats. Azo-dye binding protein is a specific cytosolic protein involved in the translocation of azo-dye carcinogen metabolites from liver cytoplasm into the nucleus. Administration of vitamin A (40,000 and 50,000 IU), L-ascorbic acid (500 and 1000 mg) and vitamin E succinate (200-500 mg) reduced the amount of azo-dye binding protein in liver of rats treated with DAB. Supplementation of high doses of vitamin A acetate, vitamin A palmitate, sodium ascorbate, ascorbyl palmitate and vitamin E acetate had no effect on the quantity of azo-dye binding protein in liver. When the vitamin mixture was given, the level of azo-dye binding protein decreased in the liver at all the studied doses, which may be due to their synergistic effect.

Ascorbic acid, catalase and chlorpromazine reduce cryopreservation-induced damages to crossbred bull spermatozoa.

PubMed

Paudel, K P; Kumar, S; Meur, S K; Kumaresan, A

2010-04-01

The present study evaluated the effectiveness of ascorbic acid, catalase, chlorpromazine and their combinations in reducing the cryodamages to crossbred bull (Bos taurus x Bos indicus) spermatozoa. A total of 32 ejaculates (eight each from four bulls) were diluted in Tris-citric acid-fructose-egg yolk-glycerol extender. Each ejaculate was split into six parts (five treatment and one control). Treatment groups included 10 mm ascorbic acid, 0.1 mm chlorpromazine, 200 IU/ml catalase, 10 mm ascorbic acid + 0.1 mm chlorpromazine or 200 IU/ml catalase + 0.1 mm chlorpromazine in the extender. Fluorescent probes (Fluorescein isothiocyanate--Pisum sativum agglutinin + Propidium iodide) were used for the assessment of spermatozoa viability and acrosomal status. The proportion of acrosome intact live (AIL), acrosome intact dead, acrosome reacted live and acrosome reacted dead sperm was assessed in fresh, equilibrated and frozen-thawed semen. The functional status of the sperm was assessed using hypo-osmotic sperm swelling test (HOSST). Activities of acrosin and hyaluronidase enzyme were also determined. Lipid peroxidation level was assayed based on the melonaldehyde (MDA) production. In cryopreserved semen, the values of AIL spermatozoa, HOSST response, hyaluronidase and acrosin activity were reduced by 53%, 47%, 34% and 54%, respectively from their initial values in fresh semen. However, MDA level was threefold higher in the frozen-thawed sperm compared with fresh sperm. Significant (p < 0.05) improvement in motility, viability, HOSST response, retention of hyaluonidase and acrosin and reduction in MDA was recorded in ascorbic acid, catalase, ascorbic acid + chlorpromazine and catalase + chlorpromazine incorporated groups. The percentage of AIL sperm was significantly (p < 0.05) higher in ascorbic acid, catalase and ascorbic acid + chlorpromazine incorporated groups compared with the control. Chlorpromazine alone did not improve the post-thaw semen quality but when combined

Ascorbic Acid Repletion: A Possible Therapy for Diabetic Macular Edema?

PubMed Central

May, James M.

2016-01-01

Macular edema poses a significant risk for visual loss in persons with diabetic retinopathy. It occurs when plasma constituents and fluid leak out of damaged retinal microvasculature in the area of the macula, causing loss of central vision. Apoptotic loss of pericytes surrounding capillaries is perhaps the earliest feature of diabetic vascular damage in the macula, which is also associated with dysfunction of the endothelium and loss of the otherwise very tight endothelial permeability barrier. Increased oxidative stress is a key feature of damage to both cell types, mediated by excess superoxide from glucose-induced increases in mitochondrial metabolism, as well as by activation of the receptor for advanced glycation end products (RAGE). The latter in turn activates multiple pathways, some of which lead to increased oxidative stress, such as those involving NF-κB, NADPH oxidase, and endothelial nitric oxide synthase. Such cellular oxidative stress is associated with low cellular and plasma ascorbic acid levels in many subjects with diabetes in poor glycemic control. Whether repletion of low ascorbate in retinal endothelium and pericytes might help to prevent diabetic macular edema is unknown. However, cell culture studies show that the vitamin prevents high-glucose and RAGE-induced apoptosis in both cell types, that it preserves nitric oxide generated by endothelial cells, and that it tightens the leaky endothelial permeability barrier. Although these findings need to be confirmed in pre-clinical animal studies, it is worth considering clinical trials to determine whether adequate ascorbate repletion is possible and whether it might help to delay or even reverse early diabetic macular edema. PMID:26898503

D-Glucosone and L-sorbosone, putative intermediates of L-ascorbic acid biosynthesis in detached bean and spinach leaves. [Phaseolus vulgaris L. ; Spinacia oleracea L

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saito, Kazumi; Nick, J.A.; Loewus, F.A.

D-(6-{sup 14}C)Glucosone that had been prepared enzymically from D-(6-{sup 14}C)glucose was used to compare relative efficiencies of these two sugars for L-ascorbic acid (AA) biosynthesis in detached bean (Phaseolus vulgaris L., cv California small white) apices and 4-week-old spinach (Spinacia oleracea L., cv Giant Noble) leaves. At tracer concentration, {sup 14}C from glucosone was utilized by spinach leaves for AA biosynthesis much more effectively than glucose. Carbon-14 from (6-{sup 14}C)glucose underwent considerable redistribution during AA formation, whereas {sup 14}C from (6-{sup 14}C)glucosone remained almost totally in carbon 6 of AA. In other experiments with spinach leaves, L-(U-{sup 14}C)sorbosone was foundmore » to be equivalent to (6-{sup 14}C)glucose as a source of {sup 14}C for AA. In the presence of 0.1% D-glucosone, conversion of (6-{sup 14}C) glucose into labeled AA was greatly repressed. In a comparable experiment with L-sorbosone replacing D-glucosone, the effect was much less. The experiments described here give substance to the proposal that D-glucosone and L-sorbosone are putative intermediates in the conversion of D-glucose to AA in higher plants.« less

Relative hyperoxaluria, crystalluria and haematuria after megadose ingestion of vitamin C.

PubMed

Auer, B L; Auer, D; Rodgers, A L

1998-09-01

Long-term or high-dosage consumption of vitamin C may play a role in calcium oxalate kidney stone formation. The present study was undertaken to determine the biochemical and physicochemical risk factors in a male subject who developed haematuria and calcium oxalate crystalluria after ingestion of large doses of ascorbic acid for 8 consecutive days. Twenty-four-hour urine samples were collected before and during the ascorbic acid ingestion period as well as after the detection of haematuria. A special procedure was implemented for urine collections to allow for oxalate, ascorbate and other urinalysis. Oxalate was determined in the presence of EDTA to prevent in vitro conversion to ascorbic acid, whereas ascorbate itself was determined by manual titration in a redox method using the dye dichlorophenolindophenol. Urinalysis data were used to compute calcium oxalate relative supersaturations and Tiselius risk indices, whereas scanning electron microscopy was used to examine urinary deposits. Oxalate excretion increased by about 350% during ascorbate ingestion before haematuria. Ascorbate concentrations also increased dramatically but appeared to reach a plateau maximum. Increasing calcium excretion was accompanied by decreasing potassium and phosphate values. The calcium oxalate relative supersaturation and Tiselius risk index increased during vitamin C ingestion and large aggregates of calcium oxalate dihydrate crystals were observed by scanning electron microscopy immediately after the detection of haematuria. High percentage metabolic conversion of ascorbate to oxalate in this subject caused relative hyperoxaluria and crystalluria, the latter manifesting itself as haematuria. Clinicians need to be alerted to the potential dangers of large dose ingestion of vitamin C in some individuals.

Monitoring of oxidation steps of ascorbic acid redox reaction by kinetics-sensitive voltcoulometry in unsupported and supported aqueous solutions and real samples.

PubMed

Orlický, Jozef; Gmucová, Katarína; Thurzo, Ilja; Pavlásek, Juraj

2003-04-01

Aqueous solutions of ascorbic acid in unsupported and supported aqueous solutions and real samples were studied by the kinetics-sensitive double-step voltcoulommetric method with the aim to contribute to a better understanding of its behavior in biological systems. The data obtained from measurements made on analytes prepared in the laboratory, as well as those made on real samples (some commercial orange drinks, flash of the fresh fruits) point to the redox reaction of L-ascorbic acid (L-AH2) being very sensitive to both the presence of dissolved gaseous species (O2, CO2) and the ionic strenght in the analyte. Either the dissolved gaseous species, or the higher ionic strength caused by both the presence of supporting electrolyte and increased total concentration of ascorbic acid, respectively, give birth to the degradation of L-AH2. Naturally, the highest percentage of L-AH2 was spotted in fresh fruit.

Reduction of the DNA damages, Hepatoprotective Effect and Antioxidant Potential of the Coconut Water, ascorbic and Caffeic Acids in Oxidative Stress Mediated by Ethanol.

PubMed

Bispo, Vanderson S; Dantas, Lucas S; Chaves, Adriano B; Pinto, Isabella F D; Silva, Railmara P DA; Otsuka, Felipe A M; Santos, Rodrigo B; Santos, Aline C; Trindade, Danielle J; Matos, Humberto R

2017-01-01

Hepatic disorders such as steatosis and alcoholic steatohepatitis are common diseases that affect thousands of people around the globe. This study aims to identify the main phenol compounds using a new HPLC-ESI+-MS/MS method, to evaluate some oxidative stress parameters and the hepatoprotective action of green dwarf coconut water, caffeic and ascorbic acids on the liver and serum of rats treated with ethanol. The results showed five polyphenols in the lyophilized coconut water spiked with standards: chlorogenic acid (0.18 µM), caffeic acid (1.1 µM), methyl caffeate (0.03 µM), quercetin (0.08 µM) and ferulic acid (0.02 µM) isomers. In the animals, the activity of the serum γ-glutamyltranspeptidase (γ-GT) was reduced to 1.8 I.U/L in the coconut water group, 3.6 I.U/L in the ascorbic acid group and 2.9 I.U/L in the caffeic acid groups, when compared with the ethanol group (5.1 I.U/L, p<0.05). Still in liver, the DNA analysis demonstrated a decrease of oxidized bases compared to ethanol group of 36.2% and 48.0% for pretreated and post treated coconut water group respectively, 42.5% for the caffeic acid group, and 34.5% for the ascorbic acid group. The ascorbic acid was efficient in inhibiting the thiobarbituric acid reactive substances (TBARS) in the liver by 16.5% in comparison with the ethanol group. These data indicate that the green dwarf coconut water, caffeic and ascorbic acids have antioxidant, hepatoprotective and reduced DNA damage properties, thus decreasing the oxidative stress induced by ethanol metabolism.

Influence of dietary magnesium on mineral, ascorbic acid and glutathione concentrations in tissues of a freshwater fish, the common carp.

PubMed

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.

Characterization of the galactono-1,4-lactone dehydrogenase from pepper fruits and its modulation in the ascorbate biosynthesis. Role of nitric oxide.

PubMed

Rodríguez-Ruiz, Marta; Mateos, Rosa M; Codesido, Verónica; Corpas, Francisco J; Palma, José M

2017-08-01

Pepper fruit is one of the highest vitamin C sources of plant origin for our diet. In plants, ascorbic acid is mainly synthesized through the L-galactose pathway, being the L-galactono-1,4-lactone dehydrogenase (GalLDH) the last step. Using pepper fruits, the full GalLDH gene was cloned and the protein molecular characterization accomplished. GalLDH protein sequence (586 residues) showed a 37 amino acids signal peptide at the N-terminus, characteristic of mitochondria. The hydrophobic analysis of the mature protein displayed one transmembrane helix comprising 20 amino acids at the N-terminus. By using a polyclonal antibody raised against a GalLDH internal sequence and immunoblotting analysis, a 56kDa polypeptide cross-reacted with pepper fruit samples. Using leaves, flowers, stems and fruits, the expression of GalLDH by qRT-PCR and the enzyme activity were analyzed, and results indicate that GalLDH is a key player in the physiology of pepper plants, being possibly involved in the processes which undertake the transport of ascorbate among different organs. We also report that an NO (nitric oxide)-enriched atmosphere enhanced ascorbate content in pepper fruits about 40% parallel to increased GalLDH gene expression and enzyme activity. This is the first report on the stimulating effect of NO treatment on the vitamin C concentration in plants. Accordingly, the modulation by NO of GalLDH was addressed. In vitro enzymatic assays of GalLDH were performed in the presence of SIN-1 (peroxynitrite donor) and S-nitrosoglutahione (NO donor). Combined results of in vivo NO treatment and in vitro assays showed that NO provoked the regulation of GalLDH at transcriptional and post-transcriptional levels, but not post-translational modifications through nitration or S-nitrosylation events promoted by reactive nitrogen species (RNS) took place. These results suggest that this modulation point of the ascorbate biosynthesis could be potentially used for biotechnological purposes to

Determination of furan precursors and some thermal damage markers in baby foods: ascorbic acid, dehydroascorbic acid, hydroxymethylfurfural and furfural.

PubMed

Mesías-García, Marta; Guerra-Hernández, Eduardo; García-Villanova, Belén

2010-05-26

The presence of ascorbic acid (AA), vitamin C (AA + dehydroascorbic acid (DHAA)) and furfural as potential precursors of furan in commercial fruit and vegetable jarred baby food was studied. Hydroxymethylfurfural (HMF) was also determined and used, together with furfural levels, as markers of thermal damage. AA, calculated DHAA and vitamin C values ranged between 22.4 and 103, 2.9 and 13.8, and 32.1 and 113.2 mg/100 g, respectively, in fruit-based baby food. However, no trace of AA was found in the vegetable-based baby food samples tested, probably because these samples are not enriched in vitamin C and the content of this vitamin in fresh vegetables is destroyed during processing. Furfural values ranged from not detected to 236 microg/100 g, being higher in vegetable samples than in fruit samples possibly because of greater AA degradation favored by a higher pH in the vegetable samples. HMF values (range: not detected-959 microg/100 g), however, were higher in the fruit samples, probably due to greater carbohydrate content degradation and as a consequence of the Maillard reaction, favored by a lower pH in these samples. According to these results, HMF would be the optimum indicator of thermal treatment for fruits, and furfural for vegetables. The higher furfural content of vegetable baby food could be considered an index of greater AA degradation and, therefore, the furan content might be higher in this kind of sample than in fruit-based baby food.

[Phytochemical analysis of Hippophae rhamnoides L. fruits from Russian varieties cultivated in Finland and food products containing them].

PubMed

Kosman, V M; Faustova, N M; Pozharitskaia, O N; Shikov, A N; Galambozi, B; Makarov, V G

2009-01-01

Results of phytochemical analysis of the berries from six Russian Hippophae rhamnnoides L. varieties (Augustinka, Botanitseskaja, Ljubitelskaja, Vorobjvskaja, Pertsik, Trofimovskaja), cultivated in Finland, are presented. The contents of ascorbic acid (vitamin C), tocopherols (vitamin E), total flavonoid (vitamin P), total carotenoid (vitamin A) and total organic acids were analyzed in unfreezed berries. The same parameters were defined in food products (jelly, sweet sauce and compote) containing fruits of three Hippophae rhamnoides L. varieties (Botanitseskaja, Ljubitelskaja and Trofimovskaja). According to the results, Russian Hippophae rhamnoides L. varieties can be cultivated in South-Finland and different kinds of food products with high quality and concentration of biologically active compounds may be prepared from these berries.

A novel method for the determination of ascorbic acid and antioxidant capacity in Opuntia ficus indica using in vivo microdialysis.

PubMed

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. Copyright © 2013 Elsevier Ltd. All rights reserved.

Ascorbic acid glucoside reduces neurotoxicity and glutathione depletion in mouse brain induced by nitrotriazole radiosensitazer.

PubMed

Cherdyntseva, Nadezda V; Ivanova, Anna A; Ivanov, Vladimir V; Cherdyntsev, Evgeny; Nair, Cherupally Krishnan Krishnan; Kagiya, Tsutomu V

2013-01-01

To investigate the potential of the anti-oxidant ascorbic acid glucoside (AA-2G) to modulate neurotoxicity induced by high doses of nitrotriazole radiosensitizer. Male and female C56Bl/6xCBA hybrid mice aged 8-14 weeks (weight 18-24 g) were used. Nitrotriazole drug radiosensitizer sanazole at a high dose of 2, 1 g/kg was per os administered to induce neurotoxicity at mice. Ascorbic acid glucoside was given 30 min before the sanazole administration. Serum ascorbic acid, brain glutathione level, as well as behavioral performance using open field apparatus were measured. Administration of high (non-therapeutic) doses of the nitrotriazole drug sanazole results in neurotoxicity in mice as evidenced from behavioral performance, emotional activity and depletion of the cellular antioxidant, glutathione, in the brain. The serum levels of ascorbic acid was also found reduced in high dose sanazole treated animals. Per os administration of ascorbic acid glucoside significantly reduced the neurotoxicity. This effect was associated with the prevention of glutathione depletion in mouse brain and restoring the ascorbic acid level in serum. Administration of ascorbic acid glucoside, but not ascorbic acid, before sanazole administration protected from sanazole-induced neurotoxicity by preventing the decrease in the brain reduced glutathione level and providing high level of ascorbic acid in plasma.

Preparation of steppogenin and ascorbic acid, vitamin E, butylated hydroxytoluene oil-in-water microemulsions: Characterization, stability, and antibrowning effects for fresh apple juice.

PubMed

Tao, Jing; Zhu, Qin; Qin, Fang; Wang, Mingfu; Chen, Jie; Zheng, Zong-Ping

2017-06-01

Oil-in-water microemulsions (O/W MEs) allow the preparation of insoluble compounds into liquid. In this study, we prepared O/W MEs to improve the solubility and stability of steppogenin (S) in aqueous liquid, and studied their ability to inhibit fresh apple juice browning. The ME technique greatly increased steppogenin solubility up to 3000-fold higher than that in water. All SMEs demonstrated good stability after acceleration and long-term storage. In particular, 0.01% SME was associated with dramatic inhibition of fresh apple juice browning after 24h at room temperature and 7days at 4°C, and its antibrowning effects were further improved when combined with 0.05% ascorbic acid. On the other hand, simultaneous encapsulation of steppogenin with vitamin E or butylated hydroxytoluene into ME did not greatly improve SME antibrowning effects. Taken together, these results suggested that steppogenin might serve as a potential antibrowning agent to preserve fresh apple juice. Copyright © 2016 Elsevier Ltd. All rights reserved.

Changes in carotenoids, ascorbic acids, and quality characteristics by the pickling of paprika (Capsicum annuum l.) cultivated in Korea.

PubMed

Park, Jihyun; Kim, Suna; Moon, Bokyung

2011-09-01

Paprika (Capsicum annuum L.) is widely used as a healthy vegetable having antitumor-promoting activity and reducing or preventing chronic disease. Paprika has been mostly consumed as fresh fruit, and as food colorants such as oleoresin or pigment powder. In this study, pickled paprika was produced and its quality characteristics were monitored during storage (35 °C for 42 d). Carotenoid composition, ascorbic acid, total phenolic contents, and antioxidant activities were also analyzed. Five carotenoid compounds were identified in the pickled paprika and after 42 d of storage, total carotenoid content was 2.44 ± 0.69 mg/100g fresh weight(fw) and ascorbic acid content was 50.90 ± 3.26 mg/100g dry weight (dw). 2,2'-azino-di-(3-ethylbenzthiazoline sulphonate (ABTS) radical-scavenging activity of the pickled paprika was maintained above 70% until 28 d of storage, and then decreased to 47% of the initial activity. pH increased from 2.78 ± 0.06 to 3.10 ± 0.03 at 14 d and was then maintained until 42 d. Soluble solids increased gradually and color values including L*, a*, and b* decreased during storage. Hardness also decreased from 6.17 ± 0.18 kg force to 1.90 ± 0.60 kg force during storage. The overall taste of the pickled paprika was deemed to be good until 28 d of storage. Pickled paprika showed a possibility as a new pickled product. We demonstrated that paprika could be processed as a new pickled product with extended storage. Pickled paprika was produced and its quality characteristics along with phytochemical contents were monitored during storage. Phytochemicals, including ascorbic acid and polyphenols in pickled paprika were considerably retained and visual color was satisfactory during storage. Texture was deemed to be satisfactory for 4 wk. Considering that our experiment was performed at a relatively high temperature and without the addition of calcium for the improvement of texture, our results are quite promising in order to produce new pickled

Interrelationship of dietary lipids and ascorbic acid with hepatic enzymes of cholesterol metabolic pathway.

PubMed

Sen, S; Mukherjee, S

1997-01-01

Effect of unsaturated and saturated fats on cholesterol metabolism was studied in ascorbate sufficient and deficient guineapigs. Experimental animals were made chronic ascorbic acid deficient by allowing oral intake of 0.5 mg ascorbic acid/day/animal. Elevation in serum and liver cholesterol and triglyceride along with depression in cholesterol oxidation and 7 alpha-hydroxylation in liver was observed in unsaturated fat fed guineapigs with ascorbate deficiency. Liver microsomal cytochrome P-450 level was found to be low in ascorbate deficient animals. Polyunsaturated fat intake could not lower the serum cholesterol level in ascorbate deficiency. Today polyunsaturated fat in the diet is encouraged all over the world for its hypocholesterolemic effect. This study indicates that polyunsaturated fat intake with ascorbic acid deficiency may produce hypercholesterolemia.

Change in the ascorbic acid, total phenol and antioxidant activity of sun-dried commonly consumed green leafy vegetables in Nigeria.

PubMed

Oboh, G; Akindahunsi, A A

2004-01-01

Sun-drying of green leafy vegetables is popularly practised in many homes in Nigeria, as a way of preserving green leafy vegetables for future use. This project sought to investigate the effect of this method of preservation of vegetables on the antioxidant phytoconstituent (Vitamin C and Total phenol) and activity (reducing property and free radical scavenging ability) of some commonly consumed green leafy vegetables in Nigeria namely Structium sparejanophora (Ewuro-odo), Amarantus cruentus (Atetedaye), Telfairia occidentalis (Ugu), Baselia allia (Amunu tutu), Solanum macrocarpon (Igbagba), Corchorus olitorius (Ewedu), Vernonia anygdalina (Ewuro) and Occimum graticimum (Efinrin). The edible portions of the green leafy vegetables were sun-dried for seven days before determining the Vitamin C and total phenol content, as well as the reducing property and free radical scavenging ability. The result of the study revealed that sun-drying of green leafy vegetables cause a significant (P < 0.05) decrease in the Vitamin C content (16.67-64.68% loss). Conversely it leads to a significant increase in the total phenol content (6.45-223.08% gain), reducing property (16.00-362.50% gain) and free radical scavenging ability (126.00-5757.00% gain) of the green leafy vegetables. It could therefore be concluded that a significant decrease (P < 0.05) in Vitamin C content caused by sun- drying will not reduce the antioxidant activity of the green leafy vegetable, moreover, the phenol constituent of the green leafy vegetables contributes more to the antioxidant properties of vegetables than ascorbic acid, as its increase on sun-drying cause a significant (P < 0.05) increases in the antioxidant properties of the green leafy vegetables, irrespective of the decrease in the ascorbic acid content.

Ascorbic Acid Intake and Oxalate Synthesis

PubMed Central

Knight, John; Madduma-Liyanage, Kumudu; Mobley, James A.; Assimos, Dean G.; Holmes, Ross P.

2016-01-01

In humans approximately 60 mg of ascorbic acid (AA) breaks down in the body each day and has to be replaced by a dietary intake of 70 mg in females and 90 mg in males to maintain optimal health and AA homeostasis. The breakdown of AA is non-enzymatic and results in oxalate formation. The exact amount of oxalate formed has been difficult to ascertain primarily due to the limited availability of healthy human tissue for such research and the difficulty in measuring AA and its breakdown products. The breakdown of 60 mg of AA to oxalate could potentially result in the formation of up to 30 mg oxalate per day. This exceeds our estimates of the endogenous production of 10 – 25 mg oxalate per day, indicating that degradative pathways that do not form oxalate exist. In this review we examine what is known about the pathways of AA metabolism and how oxalate forms. We further identify how gaps in our knowledge may be filled to more precisely determine the contribution of AA breakdown to oxalate production in humans. The use of stable isotopes of AA to directly assess the conversion of vitamin to oxalate should help fill this void. PMID:27002809

Intravenous ascorbic acid to prevent and treat cancer-associated sepsis?

PubMed Central

2011-01-01

The history of ascorbic acid (AA) and cancer has been marked with controversy. Clinical studies evaluating AA in cancer outcome continue to the present day. However, the wealth of data suggesting that AA may be highly beneficial in addressing cancer-associated inflammation, particularly progression to systemic inflammatory response syndrome (SIRS) and multi organ failure (MOF), has been largely overlooked. Patients with advanced cancer are generally deficient in AA. Once these patients develop septic symptoms, a further decrease in ascorbic acid levels occurs. Given the known role of ascorbate in: a) maintaining endothelial and suppression of inflammatory markers; b) protection from sepsis in animal models; and c) direct antineoplastic effects, we propose the use of ascorbate as an adjuvant to existing modalities in the treatment and prevention of cancer-associated sepsis. PMID:21375761

Long-distance transport of L-ascorbic acid in potato

PubMed Central

Tedone, Luigi; Hancock, Robert D; Alberino, Salvatore; Haupt, Sophie; Viola, Roberto

2004-01-01

Background Following on from recent advances in plant AsA biosynthesis there is increasing interest in elucidating the factors contributing to the L-ascorbic acid (AsA) content of edible crops. One main objective is to establish whether in sink organs such as fruits and tubers, AsA is synthesised in situ from imported photoassimilates or synthesised in source tissues and translocated via the phloem. In the current work we test the hypothesis that long-distance transport is involved in AsA accumulation within the potato tuber, the most significant source of AsA in the European diet. Results Using the EDTA exudation technique we confirm the presence of AsA in the phloem of potato plants and demonstrate a correlation between changes in the AsA content of source leaves and that of phloem exudates. Comparison of carboxyflourescein and AgNO3 staining is suggestive of symplastic unloading of AsA in developing tubers. This hypothesis was further supported by the changes in AsA distribution during tuber development which closely resembled those of imported photoassimilates. Manipulation of leaf AsA content by supply of precursors to source leaves resulted in increased AsA content of developing tubers. Conclusion Our data provide strong support to the hypothesis that long-distance transport of AsA occurs in potato. We also show that phloem AsA content and AsA accumulation in sink organs can be directly increased via manipulation of AsA content in the foliage. We are now attempting to establish the quantitative contribution of imported AsA to overall AsA accumulation in developing potato tubers via transgenic approaches. PMID:15377389

L-Ascorbic acid metabolism during fruit development in an ascorbate-rich fruit crop chestnut rose (Rosa roxburghii Tratt).

PubMed

Huang, Ming; Xu, Qiang; Deng, Xiu-Xin

2014-09-01

Chestnut rose (Rosa roxburghii Tratt) is a fruit crop that contains unusually high levels of l-ascorbic acid (AsA; ∼1300 mg 100g(-1) FW). To explore the mechanisms underlying AsA metabolism, we investigated the distribution and abundance of AsA during fruit development. We also analyzed gene expression patterns, enzyme activities, and content of metabolites related to AsA biosynthesis and recycling. AsA first accumulated during late fruit development and continued to accumulate during ripening, with the highest accumulation rate near fruit maturity. The redox state of AsA in fruit was also enhanced during late fruit development, while leaf and other tissues had much lower levels of AsA and the redox state of AsA was lower. In mature fruit, AsA was mainly distributed in the cytoplasm of the mesocarp. Correlation analysis suggested that the gene expression patterns, enzyme activities, and related metabolite concentrations involved in the l-galactose pathway showed relatively high correlations with the accumulation rate of AsA. The gene expression pattern and activity of dehydroascorbate reductase (DHAR, EC 1.8.5.1) correlated strongly with AsA concentration, possibly indicating the crucial role of DHAR in the accumulation of high levels of AsA in chestnut rose fruit. Over expression of DHAR in Arabidopsis significantly increased the reduced AsA content and redox state. This was more effective than over expression of the l-galactose pathway gene GDP-d-mannose-3,5-epimerase (EC 5.1.3.18). These findings will enhance understanding of the molecular mechanisms regulating accumulation of AsA in chestnut rose. Copyright © 2014 Elsevier GmbH. All rights reserved.

[Enrichment effect of vitamin-deficient diet of rats by polyunsaturated fatty acids omega-3 on vitamin biomarkers and antioxidant status].

PubMed

Vrzhesinskaia, O A; Beketova, V M; Kodentsova, O G; Pereverzeva, O G; Kosheleva, O V; Sokol'nikov, A A; Kulakova, S N; Baturina, V A; Soto, S Kh

2013-01-01

Using the model of combined vitamin deficiency based on 5-fold reduction of the amount of vitamin mixture in semi-synthetic diet and on vitamin E exclusion from the mixture, the influence of omega-3 polyunsaturated fatty acids (PUFA) on vitamin and antioxidant status has been investigated. The enrichment of rat diet with PUFA was achieved by replacing of sunflower oil (4.5% of the diet) on linseed oil. This substitute led to omega-3 PUFA elevation from 0.03 to 2.4 g per 100 g of food and PUFA and saturated fatty acids diet ratio increased from 1.3 to 1.9. The diet treatment with PUFA did not affect blood plasma retinol concentration and total vitamin A (retinol palmitate and retinol) rat liver content, while liver retinol significantly 1,5-fold elevated. Despite of preliminary equation of tocopherols content in vegetable oils (up to 60 IU per 100 g by adding dl-alpha-tocopherol to linseed oil) the consuming of linen oil deteriorated animal vitamin E supply. The liver alpha-tocopherol content significantly decreased by 14%, its blood plasma concentration insignificantly decreased by 26%, while the amount of beta - and gamma-tocopherol significantly increased in 5,4-fold. At the same deprivation of vitamin D in the diet of rats treated with linseed oil 25(OH)D blood plasma concentration was 1,3-fold higher compared with the animals treated with sunflower oil, but the difference did not reach significance reliable. In this case, this index had significant differences from that of the receiving adequate diet rats in control group, having 2-fold higher concentration of vitamin D transport form in blood plasma. PUFA enrichment of the combined vitamin-deficit diet did not affect liver level of vitamin C, vitamin B1 and vitamin B2. Contrary to the assumptions, the enrichment with PUFA of vitamin-deficient diet did not lead to a further increase of liver MDA level and a decrease of liver ascorbic acid content, which is typical for animals in combined vitamin deficiency. The

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

EPA Science Inventory

PLASMID DNA DAMAGE CAOUSED BY METHYLATED ARSENICALS, ASCORBIC ACID AND HUMAN LIVER FERRITIN

ABSTRACT

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. ...

Plasma Homocysteine, Serum Folic Acid, Serum Vitamin B12, Serum Vitamin B6, MTHFR, and Risk of Normal-Tension Glaucoma.

PubMed

Li, Jinmiao; Xu, Fan; Zeng, Rui; Gong, Haijun; Lan, Yuqing

2016-02-01

This meta-analysis aims to comprehensively evaluate the association between total homocysteine (tHcy) levels, serum folic acid, vitamin B12, vitamin B6 levels, methylenetetrahydrofolate reductase (MTHFR) C677T genotype, and risk of normal-tension glaucoma (NTG). A systematic search of the EMBASE and PubMed databases was performed to evaluate plasma tHcy levels, serum folic acid, B vitamins' mean difference, and odds ratios of MTHFR C677T genotype between cases and controls. A total of 7 studies including 458 cases and 555 controls meeting the inclusion criteria were involved in this meta-analysis. There were 4 studies for tHcy (149 cases and 148 controls), 2 studies for vitamin B6, vitamin B12, and folate (90 cases and 82 controls), and 4 studies for MTHFR (343 cases and 449 controls). Overall, the mean plasma tHcy levels, serum folic acids, vitamin B12, and vitamin B6 levels were 1.16 μmol/L [95% confidence interval (CI), -0.13, 2.45], -0.62 μmol/L (95% CI, -1.98, 0.74), 5.81 μmol/L (95% CI, -3.53, 15.14), and -16.79 μmol/L (95% CI, -86.09, 52.51). MTHFR TT genotype was found to be unrelated to NTG risk (odds ratio=1.08; 95% CI, 0.69, 1.69). NTG is not associated with elevated plasma tHcy, serum folic acid, serum vitamin B12, serum vitamin B6, and MTHFR C677T genotype.

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

PubMed

Dey, S K; Nayak, P; Roy, S

2001-07-01

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 (80-100 g body weight). It has been observed that the intoxication with chromium (i.p.) at the dose of 0.8 mg/100 g body weight per day for a period of 28 days causes significant increase in the level of cholesterol and decrease in the level of phospholipid of both liver and kidney. The alkaline phosphatase, 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/100 g 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.

Modification of rat detrusor muscle contraction by ascorbic acid and citric acid involving enhanced neurotransmitter release and Ca2+ influx.

PubMed

Dasgupta, Jaydip; Elliott, Ruth A; Tincello, Douglas G

2009-01-01

Consumption of carbonated soft drinks is independently associated with the development of overactive bladder (OR 1.41, 95% Cl 1.02-1.95). We have shown previously that artificial sweeteners, present in carbonated soft drinks, enhanced detrusor muscle contraction. Other constituents of soft drinks are preservatives and antioxidants, we evaluated the effects of two of these, ascorbic acid and citric acid, on the contractile response of isolated rat bladder muscle strips. Detrusor muscle strips were suspended in a perfusion organ bath. We determined the effect of ascorbic acid and citric acid on the contractile responses to electrical field stimulation (EFS) in the absence and presence of atropine, carbachol, alpha, beta methylene ATP, potassium and calcium. Ascorbic acid and citric acid (10(-7) M to 10(-3) M) enhanced the contractile response to 10 Hz EFS compared to control (P < 0.01). The frequency and amplitude of spontaneous bladder contractions were enhanced in the presence of ascorbic acid and citric acid by 14%, 21%, 21%, and 11% respectively. Ascorbic acid 10(-4) M significantly increased the atropine resistant response to EFS 5 Hz by 37% (P < 0.01) and inhibited contraction in response to carbachol 10(-4) M by 24%, (P < 0.05). Both ascorbic acid 10(-4) M and citric acid 10(-5) M significantly enhanced maximum contractile responses to alpha, beta methylene ATP, KCI and calcium compared to control. Ascorbic acid and citric acid augmented bladder muscle contraction possibly by enhanced Ca(2+) influx. Presynaptic neurotransmitter release was enhanced by ascorbic acid. Carbonated beverages containing preservatives may aggravate symptoms of OAB. (c) 2009 Wiley-Liss, Inc.

Effect of oral contraceptive agents on nutrients: II. Vitamins.

PubMed

Prasad, A S; Oberleas, D; Moghissi, K S; Stryker, J C; Lei, K Y

1975-04-01

Clinical, biochemical and nutritional data were collected from a large population of women using oral contraceptive agents. Higher incidence of abnormal clinical signs related to malnutrition were observed in the lower (B) as compared to the higher (A) socioeconomic groups, and also in the nonsupplemented groups as compared to the supplemented groups in the B subjects. As a rule the intake of oral contraceptive agent subjects of vitamin A, C, B6 and folic acid did not differ from that of the controls As expected, subjects from the supplemented groups had higher intake of vitamin A, C, B6, thiamin, riboflavin and folic acid, and A groups had higher intake of vitamin C, B6, riboflavin and folic acid. Increased plasma vitamin A and decreased carotene levels were observed in oral contraceptive agent users. In general oral contraceptive agents had little or no effect on plasma ascorbic acid. Urinary excretion of both thiamin and riboflavin in subjects using oral contraceptive agents were lower in A groups. Erythrocyte folate and plasma pyridoxal phosphate was decreased in A groups due to oral contraceptive agents. Subjects who took supplements had higher levels of plasma vitamin A, ascorbic acid and folate. But urinary thiamin and riboflavin were higher only in group A subjects who took supplements.

Bread cofortified with folic acid and vitamin B-12 improves the folate and vitamin B-12 status of healthy older people: a randomized controlled trial.

PubMed

Winkels, Renate M; Brouwer, Ingeborg A; Clarke, Robert; Katan, Martijn B; Verhoef, Petra

2008-08-01

Mandatory fortification of flour with folic acid has reduced the number of neural tube defects in North America. Concerns that high intakes of folic acid might mask vitamin B-12 deficiency in older persons have delayed the introduction of fortification in many European countries. Cofortification of flour with folic acid and vitamin B-12 could simultaneously improve folate and vitamin B-12 status. The objective was to estimate the effect of the consumption of bread fortified with modest amounts of folic acid and vitamin B-12 on folate and vitamin B-12 status in healthy older persons living in the Netherlands, where folic acid fortification is not taking place. Men and women aged 50-75 y were randomly assigned in this 12-wk double-blind, placebo-controlled trial to consume bread fortified with 138 mug folic acid and 9.6 mug vitamin B-12 daily (n = 72) or unfortified bread (n = 70). The consumption of fortified bread increased serum folate concentrations by 45% (mean: 6.3 nmol/L; 95% CI: 4.5, 8.1 nmol/L) and serum vitamin B-12 concentrations by 49% (mean: 102 pmol/L; 95% CI: 82, 122 pmol/L) relative to the placebo group. Fortified bread increased erythrocyte folate concentrations by 22% and holotranscobalamin concentrations by 35%; it decreased homocysteine concentrations by 13% and methylmalonic acid concentrations by 10%. Consumption of fortified bread decreased the proportion of individuals with marginal serum vitamin B-12 concentrations (<133 pmol/L) from 8% at enrollment to 0% after 12 wk. Bread fortified with modest amounts of folic acid and vitamin B-12 will improve folate and vitamin B-12 status and a considerable proportion of vitamin B-12 deficiency in older people. This trial was registered at clinicaltrials.gov as NCT00353353.

Oxidation of ascorbic acid by a (salen)ruthenium(VI) nitrido complex in aqueous solution.

PubMed

Wang, Qian; Man, Wai-Lun; Lam, William W Y; Lau, Tai-Chu

2014-12-25

The oxidation of ascorbic acid (H2A) by [Ru(VI)(N)(L)(MeOH)](+) in aqueous acidic solutions has the following stoichiometry: 2[Ru(VI)(N)] + 3H2A → 2[Ru(III)(NH2-HA)](+) + A. Mechanisms involving HAT/N-rebound at low pH (≤2) and nucleophilic attack at the nitride at high pH (≥5) are proposed.

Vitamin C deficiency in growing willow ptarmigan (Lagopus lagopus lagopus).

PubMed

Hanssen, I; Grav, H J; Steen, J B; Lysnes, H

1979-12-01

Willow ptarmigan chicks raised on a diet containing 265 mg ascorbic acid/kg develop scury-like symptoms and die by 4 weeks of age. If blueberry plants are given as an ad libitum supplement to this diet, the malady is prevented. We have described the clinical, pathological and histological changes which accompany this malnutrition and conclude that they are in accord with the description of scurvy in guinea pig and man. Biochemical determination of ascorbic acid synthesis in the kidney of ptarmigan chicks indicated a rate of synthesis five times that found in livers of growing white rats. Blueberry plants and many other plants found in the natural diet of ptarmigan chicks contain 2,000 to 5,000 mg ascorbic acid/kg dry weight. Feeding experiments showed that the pathological signs were avoided and that already afflicted chicks recovered if the vitamin C content of the diet was raised to 750 mg/kg dry weight of food. Since the food intake of the chicks was 5 to 8 g/day the daily requirement of external vitamin C is about 150 mg/kg body weight. To our knowledge this is the first example of an animal which, while producing vitamin C itself, requires substantial amounts of external vitamin C to survive.

Formation of an ascorbate-apatite composite layer on titanium.

PubMed

Ito, Atsuo; Sogo, Yu; Ebihara, Yuko; Onoguchi, Masahiro; Oyane, Ayako; Ichinose, Noboru

2007-09-01

An ascorbate-apatite composite layer was successfully formed on NaOH- and heat-treated titanium by coprecipitating L-ascorbic acid phosphate and low-crystalline apatite in a supersaturated calcium phosphate solution at 37 degrees C for 48 h. The supersaturated calcium phosphate solutions used have chemical compositions attainable by mixing infusion fluids officially approved for clinical use. The amount of immobilized L-ascorbic acid phosphate ranged from 1.0 to 2.3 microg mm(-2), which is most likely to be sufficient for the in vitro osteogenic differentiation of mesenchymal stem cells on titanium. Since ascorbate is important for the collagen synthesis and subsequent osteogenesis of mesenchymal stem cells, titanium coated with the ascorbate-apatite composite layer would be useful as a scaffold in bone tissue engineering and as a bone substitute.

Amperometric ascorbic acid sensor based on doped ferrites nanoparticles modified glassy carbon paste electrode.

PubMed

Dimitrijević, Teodora; Vulić, Predrag; Manojlović, Dragan; Nikolić, Aleksandar S; Stanković, Dalibor M

2016-07-01

In this study, a novel electrochemical sensor for quantification of ascorbic acid with amperometric detection in physiological conditions was constructed. For this purpose, cobalt and nickel ferrites were synthesized using microwave and ultrasound assistance, characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray powder diffraction (XRPD), and used for modification of glassy carbon paste electrode (GCPE). It was shown that introducing these nanoparticles to the structure of GCPE led to increasing analytical performance. Co ferrite modified GCPE (CoFeGCPE) showed better characteristics toward ascorbic acid sensing. The limit of detection (LOD) obtained by sensor was calculated to be 0.0270 mg/L, with linear range from 0.1758 to 2.6010 mg/L. This sensor was successfully applied for practical analysis, and the obtained results demonstrated that the proposed procedure could be a promising replacement for the conventional electrode materials and time-consuming and expensive separation methods. Copyright © 2016 Elsevier Inc. All rights reserved.

Ascorbic acid and sodium benzoate synergistically aggravates testicular dysfunction in adult Wistar rats.

PubMed

Kehinde, Olaniyi S; Christianah, Oyewopo I; Oyetunji, Oyewopo A

2018-01-01

The effect of the concomitant use of sodium benzoate (NaB) and ascorbic acid on human health remains controversial. Therefore, the current study is designed to investigate the effect of NaB and ascorbic acid on the testicular function of adult Wistar rats. Adult Wistar rats were randomly allotted into Control (vehicle; received 1 ml of distilled water), NaB-treated (SB-treated; received 100 mg/kg body weight; b.w ), ascorbic acid-treated (AA-treated; received 150 mg/kg b.w ) and NaB+ ascorbic acid-treated (SB+AA-treated) groups. The treatment lasted for 28 days and the administration was given orally. The body weight change was monitored. Semen analysis, biochemical assay and histological examination were performed. Treatment with NaB significantly altered the cytoarchitecture of testicular tissue, sperm quality, testicular endocrine function and oxidative stress status without any alteration in body weight gain compared to control. In addition, treatment with NaB+ ascorbic acid exacerbated testicular tissue disruption, impaired sperm quality and testicular endocrine impairment with significant reduction in oxidative stress and unaltered body weight gain when compared with NaB-treated group. This study suggests that ascorbic acid and NaB synergistically aggravates testicular dysfunction. This is independent of oxidative stress status.

Ascorbic acid reduces noise-induced nitric oxide production in the guinea pig ear.

PubMed

Heinrich, Ulf-Rüdiger; Fischer, Ilka; Brieger, Jürgen; Rümelin, Andreas; Schmidtmann, Irene; Li, Huige; Mann, Wolf J; Helling, Kai

2008-05-01

Noise-induced hearing loss can be caused, among other causes, by increased nitric oxide (NO) production in the inner ear leading to nitroactive stress and cell destruction. Some studies in the literature suggest that the degree of hearing loss (HL) could be reduced in an animal model through ascorbic acid supplementation. To identify the effect of ascorbic acid on tissue-dependent NO content in the inner ear of the guinea pig, we determined the local NO production in the organ of Corti and the lateral wall separately 6 hours after noise exposure. Prospective animal study in guinea pigs. Over a period of 7 days, male guinea pigs were supplied with minimum (25 mg/kg body weight/day) and maximum (525 mg/kg body weight/day) ascorbic acid doses, and afterwards exposed to noise (90 dB sound pressure level for 1 hour). The acoustic-evoked potentials were recorded before and after noise exposure. The organ of Corti and the lateral wall were incubated differently for 6 hours in culture medium, and the degree of NO production was determined by chemiluminescence. Ascorbic acid treatment reduced the hearing threshold shift after noise exposure depending on concentration. When the maximum ascorbic acid dose was substituted, NO production was significantly reduced in the lateral wall after noise exposure and slightly reduced in the organ of Corti. Oral supplementation of the natural radical scavenger ascorbic acid reduces the NO-production rate in the inner ear in noisy conditions. This finding supports the concept of inner ear protection by ascorbic acid supplementation.

Synthesis and antioxidant properties of a new lipophilic ascorbic acid analogue.

PubMed

Cotelle, Philippe; Cotelle, Nicole; Teissier, Elisabeth; Vezin, Hervé

2003-03-20

4-(4-Hydroxyphenyl)-5-(4-hydroxyphenylmethyl)-2-hydroxyfurane-2-one 1 was prepared by an acidic dimerisation of 4-hydroxyphenylpyruvic acid and some of its antioxidant and spectroscopic properties have been measured and compared to that of ascorbic acid. 1 is as good an antioxidant as ascorbic acid in the DPPH (2,2-diphenyl-1-picryl hydrazyl radical) test and the inhibition of hydroxyl radical and a powerful inhibitor of the Cu(2+) or AAPH (2,2'-azobis-(2-amidinopropane) dihydrochloride) induced oxidation of human LDL. 1 gives a stable radical characterised by its ESR spectrum similarly to ascorbic acid but in lower concentration and with a different reactivity towards nitroxides. Theoretical calculations allow us to propose the structure for the radical formed from 1, to explain its lower stability than ascorbyl radical and to evaluate the lipophilicity of 1.

A liquid chromatography method for determination of selected amino acids, coenzymes, growth regulators, and vitamins from Cicer arietinum (L.) and Solanum lycopersicum (L.).

PubMed

Meher, Hari Charan; Gajbhiye, Vijay T; Singh, Ghanendra

2012-01-01

A bottleneck in crosstalk and QC research has been the quantification of diverse chemotypes in small amounts of tissue. An LC-UV method for estimating 28 selected metabolites of the regulatory network underlying growth, development, maintenance, vital functions, defense reactions, and food quality is reported. The method was based on binary gradient resolutions of the analytes in an RP C18 column. The mobile phase comprised solvent A [water+0.1% trifluoroacetic acid (TFA)] and B (acetonitrile + 0.085% TFA at a flow rate of 1 ml/min. Twenty-three metabolites (selected amino acids, coenzymes, growth regulators, phenolic antioxidant, and water-soluble vitamins) were detected at 254 nm, and four fat-soluble vitamins at 280 nm. Jasmonic acid was quantified at 210 nm. The RSDs of peak area and retention time for each metabolite were <5.8%. The calibration graphs were linear with R2 values ranging from 0.98 to 0.99. The LODs (microg/mL) were about 0.01-1.0 for 23 metabolites quantified at 254 nm, 0.1-0.2 for fat-soluble vitamins, and 0.1 for jasmonic acid. The recoveries ranged from 80 to 105%, with RSDs of 2.8 to 11.2%. The method has been satisfactorily applied for determination of 28 metabolites from Cicer arietinum (L.) and Solanum lycopersicum (L.). It could be an alternative and competitive method of choice that can cheaply and easily perform routine analysis for food quality and targeted metabolomics of chickpea and tomato in response to stressors.

Contrasting effects of low versus high ascorbate doses on blood pressure responses to oral nitrite in L-NAME-induced hypertension.

PubMed

Pinheiro, Lucas C; Ferreira, Graziele C; Vilalva, Kelvin H; Toledo, José C; Tanus-Santos, Jose E

2018-04-01

Nitrite reduces blood pressure (BP) in both clinical and experimental hypertension. This effect is attributable to the formation of nitric oxide (NO) and other NO-related species, which may be improved by ascorbate or other antioxidants. However, the BP responses to oral nitrite result, at least in part, of increased gastric S-nitrosothiol formation. This study tested the hypothesis that ascorbate may destroy S-nitrosothiols and therefore not all doses of ascorbate enhance the BP responses to oral nitrite. We assessed the BP responses to oral sodim nitrite (0.2 mmol/kg) in L-NAME hypertensive rats pretreated with ascorbate (0, 0.02, 0.2, or 2 mmol/kg). Plasma and gastric wall concentrations of nitrite and nitroso compounds concentrations were determined using an ozone-based reductive chemiluminescence assay. Nitrate concentrations were determined using the Griess reaction. Free thiol concentrations were determined by a colorimetric assay. The BP responses to nitrite exhibited a bell-shape profile as they were not modified by ascorbate 0.02 mmol/l, whereas the 0.2 mmol/kg dose enhanced and the 2 mmol/kg dose attenuated BP responses. In parallel with BP responses, nitrite-induced increases in plasma nitrite and RSNO species were not modified by ascorbate 0.02 mmol/l, whereas the 0.2 mmol/kg dose enhanced and the 2 mmol/kg dose attenuated them. Similar experiments were carried out with an equimolar dose of S-nitrosogluthathione. Ascorbate dose-dependently impaired the BP responses to S-nitrosogluthathione, and the corresponding increases in plasma RSNO, but not in plasma nitrite concentrations. This is the first study to show that while ascorbate dose-dependently impairs the BP responses to oral S-nitrosogluthathione, there are contrasting effects when low versus high ascorbate doses are compared with respect to its effects on the blood pressure responses to oral nitrite administration. Our findings may have special implications to patients taking

Effect of turmeric powder (Curcuma longa L.) and ascorbic acid on physical characteristics and oxidative status of fresh and stored rabbit burgers.

PubMed

Mancini, Simone; Preziuso, Giovanna; Dal Bosco, Alessandro; Roscini, Valentina; Szendrő, Zsolt; Fratini, Filippo; Paci, Gisella

2015-12-01

The objective of this study was to evaluate the effect of Curcuma longa powder and ascorbic acid on some quality traits of rabbit burgers. The burgers (burgers control with no additives; burgers with 3.5 g of turmeric powder/100g meat; burgers with 0.1g of ascorbic acid/100g meat) were analyzed at Days 0 and 7 for pH, color, drip loss, cooking loss, fatty acid profile, TBARS, antioxidant capacity (ABTS, DPPH and FRAP) and microbial growth. The addition of turmeric powder modified the meat color, produced an antioxidant capacity similar to ascorbic acid and determined a lower cooking loss than other formulations. Turmeric powder might be considered as a useful natural antioxidant, increasing the quality and extending the shelf life of rabbit burgers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Interaction between methyl glyoxal and ascorbic acid: experimental and theoretical aspects

NASA Astrophysics Data System (ADS)

Banerjee, D.; Koll, A.; Filarowski, A.; Bhattacharyya, S. P.; Mukherjee, S.

2004-06-01

The absorption spectral change of methyl glyoxal (MG) due to the interaction with ascorbic acid (AA or Vitamin C) has been investigated using steady-state spectroscopic technique. A plausible explanation for the spectral change has been discussed on the basis of hydrogen bonding interaction between the two interacting species. The equilibrium constant for the complex formation due to hydrogen bonding interaction between MG and AA has been obtained from absorption spectral changes. Ab inito calculations with DFT B3LYP/6/31G (d,p) basis sets have been used to find out the molecular structure of the hydrogen bonded complex. The O⋯H distance found in the OH⋯O hydrogen bond turns out to be quite short (1.974 Å) which is in conformity with the large value of the equilibrium constant determined experimentally.

Ebselen is a dehydroascorbate reductase mimic, facilitating the recycling of ascorbate via mammalian thioredoxin systems.

PubMed

Zhao, Rong; Holmgren, Arne

2004-02-01

Ebselen is a selanazal drug recently revealed as a highly efficient peroxiredoxin mimic catalyzing the hydroperoxide reduction by the mammalian thioredoxin system [thioredoxin (Trx), thioredoxin reductase (TrxR), and NADPH]. The mammalian Trx system is a dehydroascorbic acid reductase recycling ascorbic acid essential for cell functions. Here we report that ebselen strongly facilitated the recycling of ascorbic acid by the TrxR both with and without Trx present. Reduction of dehydroascorbic acid by TrxR has a pH optimum of 6.4, and only approximately 55% of this activity at a physiological pH of 7.4. Ebselen at 6 microM enhances this reaction three-fold and with the same pH optimum of 6.4. The mechanism of the ebselen effect is suggested to involve reduction of dehydroascorbic acid by the ebselen selenol, a highly efficient two-electron reductant. Thus, ebselen acts as an antioxidant to lower the peroxide tone inside cells and to facilitate the recycling of dehydroascorbic acid to ascorbic acid, so as to increase the radical scavenging capacity of ascorbic acid directly or indirectly via vitamin E. The high ascorbic acid recycling efficiency of ebselen at pH 6.4 may play a major role in oxidatively stressed cells, where cytosol acidosis may trigger various responses, including apoptosis.

Vitamin C transport and its role in the central nervous system

PubMed Central

May, James M.

2013-01-01

Vitamin C, or ascorbic acid, is important as an antioxidant and participates in numerous cellular functions. Although it circulates in plasma in micromolar concentrations, it reaches millimolar concentrations in most tissues. These high ascorbate cellular concentrations are thought to be generated and maintained by the SVCT2 (Slc23a2), a specific transporter for ascorbate. The vitamin is also readily recycled from its oxidized forms inside cells. Neurons in the central nervous system (CNS) contain some of the highest ascorbic acid concentrations of mammalian tissues. Intracellular ascorbate serves several functions in the CNS, including antioxidant protection, peptide amidation, myelin formation, synaptic potentiation, and protection against glutamate toxicity. The importance of the SVCT2 for CNS function is supported by the finding that its targeted deletion in mice causes widespread cerebral hemorrhage and death on post-natal day one. Neuronal ascorbate content as maintained by this protein also has relevance for human disease, since ascorbate supplements decrease infarct size in ischemia-reperfusion injury models of stroke, and since ascorbate may protect neurons from the oxidant damage associated with neurodegenerative diseases such as Alzheimer’s, Parkinson’s, and Huntington’s. The aim of this review is to assess the role of the SVCT2 in regulating neuronal ascorbate homeostasis and the extent to which ascorbate affects brain function and antioxidant defenses in the CNS. PMID:22116696

Effect of combination treatment of gamma irradiation and ascorbic acid on physicochemical and microbial quality of minimally processed eggplant (Solanum melongena L.)

NASA Astrophysics Data System (ADS)

Hussain, Peerzada R.; Omeera, A.; Suradkar, Prashant P.; Dar, Mohd A.

2014-10-01

Gamma irradiation alone and in combination with ascorbic acid was tested for preventing the surface browning and maintaining the quality attributes of minimally processed eggplant. Eggplant samples after preparation were subjected to treatment of gamma irradiation in the dose range of 0.25-1.0 kGy and to combination treatments of ascorbic acid dip at a concentration of 2.0% w/v and gamma irradiation (dose range 0.5-2.0 kGy) followed by storage at 3±1 °C, RH 80%. Studies revealed inverse correlation (r=-0.93) between the polyphenol oxidase (PPO) activity, browning index and the treatments of ascorbic acid and gamma irradiation. Combinatory treatment of 2.0% w/v ascorbic acid and 1.0 kGy gamma irradiation proved to be significantly (p≤0.05) effective in inhibiting the PPO activity, preventing the surface browning and maintaining the creamy white color and other quality attributes of minimally processed eggplant up to 6 days of refrigerated storage. Sensory evaluation revealed that control and 0.25 kGy irradiated samples were unacceptable only after 3 days of storage. Samples irradiated at 0.5 kGy and 0.75 kGy were unacceptable after 6 days of storage. Microbial analysis revealed that radiation processing of minimally processed eggplant at 1.0 kGy with and without ascorbic acid resulted in around 1 and 1.5 log reduction in yeast and mold count as well as bacterial count just after treatment and 6 days of storage therefore, enhances the microbial safety.

Glutamate receptors modulate sodium-dependent and calcium-independent vitamin C bidirectional transport in cultured avian retinal cells.

PubMed

Portugal, Camila Cabral; Miya, Vivian Sayuri; Calaza, Karin da Costa; Santos, Rochelle Alberto Martins; Paes-de-Carvalho, Roberto

2009-01-01

Vitamin C is transported in the brain by sodium vitamin C co-transporter 2 (SVCT-2) for ascorbate and glucose transporters for dehydroascorbate. Here we have studied the expression of SVCT-2 and the uptake and release of [(14)C] ascorbate in chick retinal cells. SVCT-2 immunoreactivity was detected in rat and chick retina, specially in amacrine cells and in cells in the ganglion cell layer. Accordingly, SVCT-2 was expressed in cultured retinal neurons, but not in glial cells. [(14)C] ascorbate uptake was saturable and inhibited by sulfinpyrazone or sodium-free medium, but not by treatments that inhibit dehydroascorbate transport. Glutamate-stimulated vitamin C release was not inhibited by the glutamate transport inhibitor l-beta-threo-benzylaspartate, indicating that vitamin C release was not mediated by glutamate uptake. Also, ascorbate had no effect on [(3)H] D-aspartate release, ruling out a glutamate/ascorbate exchange mechanism. 2-Carboxy-3-carboxymethyl-4-isopropenylpyrrolidine (Kainate) or NMDA stimulated the release, effects blocked by their respective antagonists 6,7-initroquinoxaline-2,3-dione (DNQX) or (5R,2S)-(1)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (MK-801). However, DNQX, but not MK-801 or 2-amino-5-phosphonopentanoic acid (APV), blocked the stimulation by glutamate. Interestingly, DNQX prevented the stimulation by NMDA, suggesting that the effect of NMDA was mediated by glutamate release and stimulation of non-NMDA receptors. The effect of glutamate was neither dependent on external calcium nor inhibited by 1,2-bis (2-aminophenoxy) ethane-N',N',N',N',-tetraacetic acid tetrakis (acetoxy-methyl ester) (BAPTA-AM), an internal calcium chelator, but was inhibited by sulfinpyrazone or by the absence of sodium. In conclusion, retinal cells take up and release vitamin C, probably through SVCT-2, and the release can be stimulated by NMDA or non-NMDA glutamate receptors.

21 CFR 582.5013 - Ascorbic acid.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ascorbic acid. 582.5013 Section 582.5013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements...

21 CFR 582.5013 - Ascorbic acid.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ascorbic acid. 582.5013 Section 582.5013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements...

21 CFR 582.5013 - Ascorbic acid.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ascorbic acid. 582.5013 Section 582.5013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements...

21 CFR 582.5013 - Ascorbic acid.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ascorbic acid. 582.5013 Section 582.5013 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements...

21 CFR 582.3013 - Ascorbic acid.

Code of Federal Regulations, 2010 CFR

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, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 582.3013...

21 CFR 582.5013 - Ascorbic acid.

Code of Federal Regulations, 2010 CFR

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, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements...

Mechanism of ascorbic acid interference in biochemical tests that use peroxide and peroxidase to generate chromophore.

PubMed

Martinello, Flávia; Luiz da Silva, Edson

2006-11-01

Ascorbic acid interferes negatively in peroxidase-based tests (Trinder method). However, the precise mechanism remains unclear for tests that use peroxide, a phenolic compound and 4-aminophenazone (4-AP). We determined the chemical mechanism of this interference, by examining the effects of ascorbic acid in the reaction kinetics of the production and reduction of the oxidized chromophore in urate, cholesterol, triglyceride and glucose tests. Reaction of ascorbic acid with the Trinder method constituents was also verified. Ascorbic acid interfered stoichiometrically with all tests studied. However, it had two distinct effects on the reaction rate. In the urate test, ascorbic acid decreased the chromophore formation with no change in its production kinetics. In contrast, in cholesterol, triglyceride and glucose tests, an increase in the lag phase of color development occurred. Of all the Trinder constituents, only peroxide reverted the interference. In addition, ascorbic acid did not interfere with oxidase activity nor reduce significantly the chromophore formed. Peroxide depletion was the predominant chemical mechanism of ascorbic acid interference in the Trinder method with phenolics and 4-AP. Distinctive effects of ascorbic acid on the reaction kinetics of urate, cholesterol, glucose and triglyceride might be due to the rate of peroxide production by oxidases.

Beta-catenin regulates vitamin C biosynthesis and cell survival in murine liver.

PubMed

Nejak-Bowen, Kari N; Zeng, Gang; Tan, Xinping; Cieply, Benjamin; Monga, Satdarshan P

2009-10-09

Because the Wnt/beta-catenin pathway plays multiple roles in liver pathobiology, it is critical to identify gene targets that mediate such diverse effects. Here we report a novel role of beta-catenin in controlling ascorbic acid biosynthesis in murine liver through regulation of expression of regucalcin or senescence marker protein 30 and L-gulonolactone oxidase. Reverse transcription-PCR, Western blotting, and immunohistochemistry demonstrate decreased regucalcin expression in beta-catenin-null livers and greater expression in beta-catenin overexpressing transgenic livers, HepG2 hepatoma cells (contain constitutively active beta-catenin), regenerating livers, and in hepatocellular cancer tissues that exhibit beta-catenin activation. Interestingly, coprecipitation and immunofluorescence studies also demonstrate an association of beta-catenin and regucalcin. Luciferase reporter and chromatin immunoprecipitation assays verified a functional TCF-4-binding site located between -163 and -157 (CTTTGCA) on the regucalcin promoter to be critical for regulation by beta-catenin. Significantly lower serum ascorbate levels were observed in beta-catenin knock-out mice secondary to decreased expression of regucalcin and also of L-gulonolactone oxidase, the penultimate and last (also rate-limiting) steps in the synthesis of ascorbic acid, respectively. These mice also show enhanced basal hepatocyte apoptosis. To test if ascorbate deficiency secondary to beta-catenin loss and regucalcin decrease was contributing to apoptosis, beta-catenin-null hepatocytes or regucalcin small interfering RNA-transfected HepG2 cells were cultured, which exhibited significant apoptosis that was alleviated by the addition of ascorbic acid. Thus, through regucalcin and L-gulonolactone oxidase expression, beta-catenin regulates vitamin C biosynthesis in murine liver, which in turn may be one of the mechanisms contributing to the role of beta-catenin in cell survival.

Effect of intravenous ascorbic acid infusion on blood loss during laparoscopic myomectomy: a randomized, double-blind, placebo-controlled trial.

PubMed

Lee, Banghyun; Kim, Kidong; Cho, Hye Yon; Yang, Eun Joo; Suh, Dong Hoon; No, Jae Hong; Lee, Jung Ryeol; Hwang, Jung Won; Do, Sang Hwan; Kim, Yong Beom

2016-04-01

Most interventions aimed at reducing bleeding during myomectomy lack sufficient evidence regarding their effectiveness. Recently, it was reported that intraoperative ascorbic acid administration effectively reduced blood loss during abdominal myomectomy. Therefore, this study aimed to investigate whether intravenous ascorbic acid infusion would affect intraoperative blood loss in women undergoing laparoscopic myomectomy. A randomized, double-blind, parallel-group, placebo-controlled trial including 50 women undergoing laparoscopic myomectomy was conducted. Women with ≤4 myomas, ≤9cm in maximum diameter were eligible. The study:control group ratio was 1:1. Starting 30minutes before anesthesia, 2g of ascorbic acid or a placebo were administered for 2hours intraoperatively. Intraoperative blood loss, the primary endpoint, was calculated as the difference between the volume of fluids acquired from suction and that used for irrigation of the abdominal cavity during surgery using constant values. Among the 50 randomized women, 1 and 3 in the study and control groups, respectively, were excluded due to withdrawal of consent, cancelation of surgery, or non-measurement of the primary endpoint. The baseline and operative characteristics were similar between the study and control groups, as was the intraoperative blood loss (193±204mL vs. 159±193mL, P=0.52). In addition, the operating time (95±29min vs. 110±52min; P=0.50) and decrease in hemoglobin level after surgery (1.9±1.31g/dL vs. 1.4±1.4g/dL; P=0.24) were similar between the study and control groups. Intravenous ascorbic acid infusion did not reduce intraoperative blood loss in women undergoing laparoscopic myomectomy. ClinicalTrials.gov, www.clinicaltrials.gov, NCT01715597. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Decalcification by ascorbic acid for immuno- and affinohistochemical techniques on the inner ear.

PubMed

Merchán-Pérez, A; Gil-Loyzaga, P; Bartolomé, M V; Remezal, M; Fernández, P; Rodríguez, T

1999-08-01

An ascorbic acid decalcifying solution was applied to immuno- and affinohistochemical studies on the inner ear. Rat inner ears fixed in 4% paraformaldehyde in PBS or in 2% acetic acid in ethanol solutions were adequately decalcified in an ascorbic acid solution, at a temperature of 4 degrees C. The decalcifying solution was prepared with 1% ascorbic acid and 0.84% sodium chloride in distilled water (pH 2.5-2.6). The decalcification time was in a direct relationship to the specimen calcification. In this study, two neuroactive substances (gamma-aminobutyric acid and calcitonin gene-related peptide), neurofilaments, and the galectine endogenous lectin were successfully detected immunohistochemically.

Folic acid fortification: why not vitamin B12 also?

PubMed

Selhub, Jacob; Paul, Ligi

2011-01-01

Folic acid fortification of cereal grains was introduced in many countries to prevent neural tube defect occurrence. The metabolism of folic acid and vitamin B12 intersect during the transfer of the methyl group from 5-methyltetrahydrofolate to homocysteine catalyzed by B12-dependent methioine synthase. Regeneration of tetrahydrofolate via this reaction makes it available for synthesis of nucleotide precursors. Thus either folate or vitamin B12 deficiency can result in impaired cell division and anemia. Exposure to extra folic acid through fortification may be detrimental to those with vitamin B12 deficiency. Among participants of National Health And Nutrition Examination Survey with low vitamin B12 status, high serum folate (>59 nmol/L) was associated with higher prevalence of anemia and cognitive impairment when compared with normal serum folate. We also observed an increase in the plasma concentrations of total homocysteine and methylmalonic acid (MMA), two functional indicators of vitamin B12 status, with increase in plasma folate under low vitamin B12 status. These data strongly imply that high plasma folate is associated with the exacerbation of both the biochemical and clinical status of vitamin B12 deficiency. Hence any food fortification policy that includes folic acid should also include vitamin B12. Copyright © 2011 International Union of Biochemistry and Molecular Biology, Inc.

Ascorbic acid deficiency stimulates hepatic expression of inflammatory chemokine, cytokine-induced neutrophil chemoattractant-1, in scurvy-prone ODS rats.

PubMed

Horio, Fumihiko; Kiyama, Keiichiro; Kobayashi, Misato; Kawai, Kaori; Tsuda, Takanori

2006-02-01

ODS rat has a hereditary defect in ascorbic acid biosynthesis and is a useful animal model for elucidating the physiological role of ascorbic acid. We previously demonstrated by using ODS rats that ascorbic acid deficiency changes the hepatic gene expression of acute phase proteins, as seen in acute inflammation. In this study, we investigated the effects of ascorbic acid deficiency on the production of inflammatory chemokine, cytokine-induced neutrophil chemoattractant-1 (CINC-1), in ODS rats. Male ODS rats (6 wk of age) were fed a basal diet containing ascorbic acid (300 mg/kg diet) or a diet without ascorbic acid for 14 d. Obvious symptoms of scurvy were not observed in the ascorbic acid-deficient rats. Ascorbic acid deficiency significantly elevated the serum concentration of CINC-1 on d 14. The liver and spleen CINC-1 concentrations in the ascorbic acid-deficient rats were significantly elevated to 600% and 180% of the respective values in the control rats. However, the lung concentration of CINC-1 was not affected by ascorbic acid deficiency. Ascorbic acid deficiency significantly elevated the hepatic mRNA level of CINC-1 (to 480% of the value in the control rats), but not the lung mRNA level. These results demonstrate that ascorbic acid deficiency elevates the serum, liver and spleen concentrations of CINC-1 as seen in acute inflammation, and suggest that ascorbic acid deficiency stimulate the hepatic CINC-1 gene expression.

Light exposure during storage preserving soluble sugar and l-ascorbic acid content of minimally processed romaine lettuce (Lactuca sativa L.var. longifolia).

PubMed

Zhan, Lijuan; Hu, Jinqiang; Ai, Zhilu; Pang, Lingyun; Li, Yu; Zhu, Meiyun

2013-01-01

Minimally processed romaine lettuce (MPRL) leaves were stored in light condition (2500lux) or darkness at 4°C for 7d. Light exposure significantly delayed the degradation of chlorophyll and decrease of glucose, reducing sugar, and sucrose content, and thus preserved more total soluble solid (TSS) content at the end of storage in comparison with darkness. While, it did not influenced starch content that progressively decreased over time. The l-ascorbic acid (AA) accumulated in light-stored leaves, but deteriorated in dark-stored leaves during storage. The dehydroascorbic acid (DHA) increased in all leaves stored in both light and dark condition, of which light condition resulted in less DHA than darkness. In addition, the fresh weight loss and dry matter significantly increased and these increases were accelerated by light exposure. Conclusively, light exposure in applied intensity effectively alleviated MPRL quality deterioration by delaying the decreases of pigments, soluble sugar, TSS content and accumulating AA. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Use of Ascorbic Acid as a Food Additive: Technical-Legal Issues

PubMed Central

Varvara, Michele; Bozzo, Giancarlo; Celano, Giuseppe; Disanto, Chiara; Pagliarone, Cosimo Nicola

2016-01-01

Ascorbic acid (C6H8O6) is an organic compound belonging to the family of monosaccharide. It is highly soluble in water, and is often called one of the secrets of the Mediterranean diet. Its use is widespread in the food industry is also important, having always been exploited for its antioxidant and stabilising ability. Many indeed are the additive formulations that take advantage of these properties. The purpose of this paper is to explain the characteristics that make ascorbic acid an important food additive and to emphasise the technical and legal issues related to its use in food productions. In particular, in the course of this employment, laws and scientific studies have been applied to the resolution of a lawsuit, having as its object the use of ascorbic acid in preparations of ground beef sold at a butcher shop. The views expressed in court by the technical consultant have led to the acquittal of the accused, in the light of the demonstrated and proven non-toxicity of the molecule and the use of a mixture of additives for the production of sausage. The European and national legislations, supported by numerous scientific studies, define the possible use of ascorbic acid according to the principle of quantum satis, and it can be used in foods for children. Our work aims to represent further evidence of the safety of use of ascorbic acid as a food additive, and – as confirmed by the legal decision reported – it wants to bring out the prospects for use of ascorbic acid for technological purposes even by registered establishments. PMID:27800425

Vitamin C: update on physiology and pharmacology

PubMed Central

Mandl, J; Szarka, A; Bánhegyi, G

2009-01-01

Although ascorbic acid is an important water-soluble antioxidant and enzyme cofactor in plants and animals, humans and some other species do not synthesize ascorbate due to the lack of the enzyme catalyzing the final step of the biosynthetic pathway, and for them it has become a vitamin. This review focuses on the role of ascorbate in various hydroxylation reactions and in the redox homeostasis of subcellular compartments including mitochondria and endoplasmic reticulum. Recently discovered functions of ascorbate in nucleic acid and histone dealkylation and proteoglycan deglycanation are also summarized. These new findings might delineate a role for ascorbate in the modulation of both pro- and anti-carcinogenic mechanisms. Recent advances and perspectives in therapeutic applications are also reviewed. On the basis of new and earlier observations, the advantages of the lost ability to synthesize ascorbate are pondered. The increasing knowledge of the functions of ascorbate and of its molecular sites of action can mechanistically substantiate a place for ascorbate in the treatment of various diseases. PMID:19508394

Evaluation of Vitamin C for Adjuvant Sepsis Therapy

PubMed Central

2013-01-01

Abstract Significance: Evidence is emerging that parenteral administration of high-dose vitamin C may warrant development as an adjuvant therapy for patients with sepsis. Recent Advances: Sepsis increases risk of death and disability, but its treatment consists only of supportive therapies because no specific therapy is available. The characteristics of severe sepsis include ascorbate (reduced vitamin C) depletion, excessive protein nitration in microvascular endothelial cells, and microvascular dysfunction composed of refractive vasodilation, endothelial barrier dysfunction, and disseminated intravascular coagulation. Parenteral administration of ascorbate prevents or even reverses these pathological changes and thereby decreases hypotension, edema, multiorgan failure, and death in animal models of sepsis. Critical Issues: Dehydroascorbic acid appears to be as effective as ascorbate for protection against microvascular dysfunction, organ failure, and death when injected in sepsis models, but information about pharmacodynamics and safety in human subjects is only available for ascorbate. Although the plasma ascorbate concentration in critically ill and septic patients is normalized by repletion protocols that use high doses of parenteral ascorbate, and such doses are tolerated well by most healthy subjects, whether such large amounts of the vitamin trigger adverse effects in patients is uncertain. Future Directions: Further study of sepsis models may determine if high concentrations of ascorbate in interstitial fluid have pro-oxidant and bacteriostatic actions that also modify disease progression. However, the ascorbate depletion observed in septic patients receiving standard care and the therapeutic mechanisms established in models are sufficient evidence to support clinical trials of parenteral ascorbate as an adjuvant therapy for sepsis. Antioxid. Redox Signal. 19, 2129–2140. PMID:23682970

KONJAC1 and 2 Are Key Factors for GDP-Mannose Generation and Affect l-Ascorbic Acid and Glucomannan Biosynthesis in Arabidopsis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sawake, Shota; Tajima, Noriaki; Mortimer, Jenny C.

Humans are unable to synthesize L-ascorbic acid (AsA), yet it is required as a cofactor in many critical biochemical reactions. The majority of human dietary AsA is obtained from plants. In Arabidopsis thaliana, a GDP-mannose pyrophosphorylase (GMPP), VITAMIN C DEFECTIVE1 (VTC1), catalyzes a rate-limiting step in AsA synthesis: the formation of GDP-Man. In this study, we identified two nucleotide sugar pyrophosphorylase-like proteins, KONJAC1 (KJC1) and KJC2, which stimulate the activity of VTC1. The kjc1kjc2 double mutant exhibited severe dwarfism, indicating that KJC proteins are important for growth and development. The kjc1 mutation reduced GMPP activity to 10% of wild-type levels,more » leading to a 60% reduction in AsA levels. On the contrary, overexpression of KJC1 significantly increased GMPP activity. The kjc1 and kjc1kjc2 mutants also exhibited significantly reduced levels of glucomannan, which is also synthesized from GDP-Man. Recombinant KJC1 and KJC2 enhanced the GMPP activity of recombinant VTC1 in vitro, while KJCs did not show GMPP activity. Yeast two-hybrid assays suggested that the stimulation of GMPP activity occurs via interaction of KJCs with VTC1. These results suggest that KJCs are key factors for the generation of GDP-Man and affect AsA level and glucomannan accumulation through the stimulation of VTC1 GMPP activity.« less

KONJAC1 and 2 Are Key Factors for GDP-Mannose Generation and Affect l-Ascorbic Acid and Glucomannan Biosynthesis in Arabidopsis.

PubMed

Sawake, Shota; Tajima, Noriaki; Mortimer, Jenny C; Lao, Jeemeng; Ishikawa, Toshiki; Yu, Xiaolan; Yamanashi, Yukiko; Yoshimi, Yoshihisa; Kawai-Yamada, Maki; Dupree, Paul; Tsumuraya, Yoichi; Kotake, Toshihisa

2015-12-01

Humans are unable to synthesize l-ascorbic acid (AsA), yet it is required as a cofactor in many critical biochemical reactions. The majority of human dietary AsA is obtained from plants. In Arabidopsis thaliana, a GDP-mannose pyrophosphorylase (GMPP), VITAMIN C DEFECTIVE1 (VTC1), catalyzes a rate-limiting step in AsA synthesis: the formation of GDP-Man. In this study, we identified two nucleotide sugar pyrophosphorylase-like proteins, KONJAC1 (KJC1) and KJC2, which stimulate the activity of VTC1. The kjc1kjc2 double mutant exhibited severe dwarfism, indicating that KJC proteins are important for growth and development. The kjc1 mutation reduced GMPP activity to 10% of wild-type levels, leading to a 60% reduction in AsA levels. On the contrary, overexpression of KJC1 significantly increased GMPP activity. The kjc1 and kjc1kjc2 mutants also exhibited significantly reduced levels of glucomannan, which is also synthesized from GDP-Man. Recombinant KJC1 and KJC2 enhanced the GMPP activity of recombinant VTC1 in vitro, while KJCs did not show GMPP activity. Yeast two-hybrid assays suggested that the stimulation of GMPP activity occurs via interaction of KJCs with VTC1. These results suggest that KJCs are key factors for the generation of GDP-Man and affect AsA level and glucomannan accumulation through the stimulation of VTC1 GMPP activity. © 2015 American Society of Plant Biologists. All rights reserved.

KONJAC1 and 2 Are Key Factors for GDP-Mannose Generation and Affect l-Ascorbic Acid and Glucomannan Biosynthesis in Arabidopsis

PubMed Central

Sawake, Shota; Tajima, Noriaki; Lao, Jeemeng; Ishikawa, Toshiki; Yu, Xiaolan; Yamanashi, Yukiko; Yoshimi, Yoshihisa; Kawai-Yamada, Maki

2015-01-01

Humans are unable to synthesize l-ascorbic acid (AsA), yet it is required as a cofactor in many critical biochemical reactions. The majority of human dietary AsA is obtained from plants. In Arabidopsis thaliana, a GDP-mannose pyrophosphorylase (GMPP), VITAMIN C DEFECTIVE1 (VTC1), catalyzes a rate-limiting step in AsA synthesis: the formation of GDP-Man. In this study, we identified two nucleotide sugar pyrophosphorylase-like proteins, KONJAC1 (KJC1) and KJC2, which stimulate the activity of VTC1. The kjc1kjc2 double mutant exhibited severe dwarfism, indicating that KJC proteins are important for growth and development. The kjc1 mutation reduced GMPP activity to 10% of wild-type levels, leading to a 60% reduction in AsA levels. On the contrary, overexpression of KJC1 significantly increased GMPP activity. The kjc1 and kjc1kjc2 mutants also exhibited significantly reduced levels of glucomannan, which is also synthesized from GDP-Man. Recombinant KJC1 and KJC2 enhanced the GMPP activity of recombinant VTC1 in vitro, while KJCs did not show GMPP activity. Yeast two-hybrid assays suggested that the stimulation of GMPP activity occurs via interaction of KJCs with VTC1. These results suggest that KJCs are key factors for the generation of GDP-Man and affect AsA level and glucomannan accumulation through the stimulation of VTC1 GMPP activity. PMID:26672069

Comparison of sarcoplasmic reticulum Ca2+-adenosine triphosphatase from vitamin E-deficient dystrophic rabbit skeletal muscle with iron-ascorbate-treated and untreated enzyme.

PubMed

Nirdnoy, W; Komaratat, P; Wilairat, P

1988-02-01

Sarcoplasmic reticulum Ca2+-ATPase from rabbit skeletal muscle has an Arrhenius curve of enzyme activity with a discontinuity at about 20 degrees C. Preparations treated with FeSO4 and ascorbic acid and from a vitamin E-deficient dystrophic rabbit have 22% of the normal activity and a linear Arrhenius curve (Promkhatkaew, D., Komaratat, P., & Wilairat, P. (1985) Biochem. Int. 10, 937-943). All three preparations were cross-linked to the same extent by dimethyl suberimidate and copper-phenanthroline reagent at temperatures above and below the temperature of the Arrhenius discontinuity. Both iron-ascorbate-treated Ca2+-ATPase and that from a vitamin E-deficient animal had 50% of the normal sulfhydryl content, but the disulfide and free amino contents were unaltered. These observations suggest that loss of sulfhydryl groups through lipid peroxidation, both in vivo and in vitro, resulted in reduction of Ca2+-ATPase activity and loss of the break in the Arrhenius plot. Changes in Ca2+-ATPase polypeptide aggregational state could not account for the discontinuity in the Arrhenius curve as revealed by the similar extent of cross-linking of the three enzyme preparations at temperatures above and below the temperature of the Arrhenius discontinuity.

Scurvy in the present times: vitamin C allergy leading to strict fast food diet.

PubMed

Shaath, Tarek; Fischer, Ryan; Goeser, Megan; Rajpara, Anand; Aires, Daniel

2016-01-15

Scurvy results from a deficiency of vitamin C, a nutrient otherwise known as ascorbic acid. Today, scurvy is rare yet emerges in select patients. The patient reported herein developed scurvy secondary to deliberate avoidance of vitamin C-rich foods. Classic cutaneous manifestations of scurvy include follicular hyperkeratosis and perifollicular hemorrhage encompassing coiled "corkscrew" hairs and hairs bent into "swan-neck" deformities. Ecchymoses, purpura, and petechiae are also characteristically prominent. Classic oral abnormalities include erythematous, swollen gingivae that hemorrhage from subtle microtrauma.Subungual linear splinter hemorrhages may also manifest as a sign of the disease. To establish the diagnosis requirements include characteristic physical exam findings, evidence of inadequate dietary intake, and rapid reversal of symptoms upon supplementation. Although unnecessary for diagnosis, histological findings demonstrate perifollicular inflammation and hemorrhage, fibrosis, and hyperkeratosis, amongst dilated hair follicles and keratin plugging. Although citrus fruit allergies have been historically documented, ascorbic acid has not been previously reported as an allergen. Although lacking absolute certainty, this report suggests a presumed case of ascorbic acid allergy based on patient history and favorable response to ascorbic acid desensitization therapy.

Stress-induced ascorbic acid depletion and cortisol production in two salmonid fishes

USGS Publications Warehouse

Wedemeyer, Gary

1969-01-01

Interrenal ascorbic acid and serum cortisol were measured in non-specificity stressed yearling coho salmon and rainbow trout.Interrenal ascorbate was markedly decreased during stress but increased to normal if adaptation occurred.Serum cortisol was elevated by non-specific stress and remained high after interrenal ascorbate had returned to initial levels.

Polyoxometalate-Graphene Nanocomposite Modified Electrode for Electrocatalytic Detection of Ascorbic Acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Weiying; Du, Dan; Gunaratne, Don

Phosphomolybdate functionalized graphene nanocomposite (PMo 12-GS) has been successfully formed on a glassy carbon electrode (GCE) for the detection of ascorbic acid (AA). The obtained PMo 12-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 PMo 12 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 ofmore » 0.5×10 -6 M. Finally, the PMo 12-GS modified electrode was employed for the determination of the AA level in vitamin C tablets, with recoveries between 96.3 and 100.8 %.« less

A GREENER SYNTHESIS OF CORE (FE, CU)-SHELL (AU, PT, PD AND AG) NANOCRYSTALS USING AQUEOUS VITAMIN C

EPA Science Inventory

A greener method to fabricate the novel core (Fe and Cu)-shell (noble metals) metal nanocrystals using aqueous ascorbic acid (vitamin C) is described. Transition metal salts such as Cu and Fe were reduced using ascorbic acid, a benign naturally available antioxidant, and then add...

Effect of antacid and ascorbic acid on serum salicylate concentration.

PubMed

Hansten, P D; Hayton, W L

1980-01-01

To determine the effect of antacid or ascorbic acid administration on plateau serum salicylate concentrations, nine healthy subjects were given each of the following treatments by balanced block design: choline salicylate (equivalent to 3.76 or 5.62 Gm/day of aspirin); choline salicylate plus magnesium-aluminum hydroxide (120 ml/day); or choline salicylate plus ascorbic acid (3 Gm/day). In subjects developing a control serum salicylate level above 10 mg/dl, antacid administration produced a decrease in serum salicylate level (mean 19.8 mg/dl vs. 15.8 mg/dl) (P less than 0.01). Ascorbic acid administration was not associated with a significant change in serum salicylate. The reduction in serum salicylate following antacid appears to be due to antacid-induced alkalinization of the urine with resultant increase in renal salicylate clearance. Antacid administration should be considered a potential cause of altered serum salicylate concentration in patients receiving large doses of salicylate.

HILIC separation and quantitation of water-soluble vitamins using diol column.

PubMed

Karatapanis, Andreas E; Fiamegos, Yiannis C; Stalikas, Constantine D

2009-04-01

Hydrophilic interaction liquid-chromatography (HILIC) in conjunction with diode array detection has been applied for the separation of selected-water-soluble vitamins using an end-capped HILIC-diol column. Vitamins with significant biological importance, such as thiamine (B(1)), riboflavin (B(2)), nicotinic acid (B(3)), nicotinamide (B(3)), pyridoxine (B(6)), folic acid (B(9)), cyanocobalamin (B(12)) and ascorbic acid (vitamin C) were simultaneously separated. Chromatographic conditions including type and percentage of organic modifier in the mobile phase, pH, type and concentration of buffer salt and flow rate were investigated. ACN was shown to offer superior separation for the compounds tested as compared to methanol, isopropanol and THF. Isocratic separation and analysis were achieved for six vitamins (B(1), B(2), nicotinic acid/nicotinamide, B(6) and C) at ACN-H(2)O 90:10, containing ammonium acetate 10 mM, triethylamine 20 mM, pH 5.0, using a flow rate of 0.8 mL/min, while a gradient was necessary to resolve a mixture of all eight water-soluble vitamins. The HILIC method was validated and successfully applied to the analysis of a pharmaceutical formulation and an energy drink negating the need for time consuming clean-up steps.

Ascorbic Acid Alleviates Water Stress in Young Peach Trees and Improves Their Performance after Rewatering.

PubMed

Penella, Consuelo; Calatayud, Ángeles; Melgar, Juan C

2017-01-01

Exogenous application of biochemicals has been found to improve water stress tolerance in herbaceous crops but there are limited studies on deciduous fruit trees. The goal of this research was to study if ascorbic acid applications could improve physiological mechanisms associated with water stress tolerance in young fruit trees. Ascorbic acid was foliarly applied at a concentration of 250 ppm to water-stressed and well-watered peach trees (control) of two cultivars ('Scarletprince' and 'CaroTiger'). Trees received either one or two applications, and 1 week after the second application all trees were rewatered to field capacity. Upon rewatering, CO 2 assimilation and stomatal conductance of water-stressed 'Scarletprince' trees sprayed with ascorbic acid (one or two applications) were similar to those of well-irrigated trees, but water-stressed trees that had not received ascorbic acid did not recover photosynthetical functions. Also, water status in sprayed water-stressed 'Scarletprince' trees was improved to values similar to control trees. On the other hand, water-stressed 'CaroTiger' trees needed two applications of ascorbic acid to reach values of CO 2 assimilation similar to control trees but these applications did not improve their water status. In general terms, different response mechanisms to cope with water stress in presence of ascorbic acid were found in each cultivar, with 'Scarletprince' trees preferentially using proline as compatible solute and 'CaroTiger' trees relying on stomatal regulation. The application of ascorbic acid reduced cell membrane damage and increased catalase activity in water-stressed trees of both cultivars. These results suggest that foliar applications of ascorbic acid could be used as a management practice for improving water stress tolerance of young trees under suboptimal water regimes.

Ascorbic acid prevents vascular dysfunction induced by oral glucose load in healthy subjects.

PubMed

De Marchi, Sergio; Prior, Manlio; Rigoni, Anna; Zecchetto, Sara; Rulfo, Fanny; Arosio, Enrico

2012-01-01

To examine the effects of oral glucose load on forearm circulatory regulation before and after ascorbic acid administration in healthy subjects. Microcirculation study with laser Doppler was performed at the hand in basal conditions, after ischemia and after acetylcholine and nitroprusside; strain gauge plethysmography was performed at basal and after ischemia. The tests were repeated in the same sequence 2 hour after oral administration of glucose (75 g). The subjects were randomised for administration of ascorbic acid (1 g bid) or placebo (sodium bicarbonate 1 g bid) for 10 days. After that, the tests were repeated before and after a new oral glucose load. Blood pressure and heart rate were monitored. Macrocirculatory flux, pressure values and heart rate were unvaried throughout the study. The glucose load caused a reduction in the hyperemic peak flow with laser Doppler and plethysmography; it reduced flux recovery time and hyperemic curve area after ischemia; acetylcholine elicited a minor increase in flux with laser Doppler. The response to nitroprusside was unvaried after glucose load as compared to basal conditions. Treatment with ascorbic acid prevented the decrease in hyperemia after glucose, detected with laser Doppler and plethysmography. Ascorbic acid prevented the decreased response to acetylcholine after glucose, the response to nitroprusside was unaffected by ascorbic acid. Results after placebo were unvaried. Oral glucose load impairs endothelium dependent dilation and hyperaemia at microcirculation, probably via oxidative stress; ascorbic acid can prevent it. Copyright © 2011 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Effect of ascorbic acid on the stability of beta-carotene and capsanthin in paprika (Capsicum annuum) powder.

PubMed

Morais, H; Rodrigues, P; Ramos, C; Forgács, E; Cserháti, T; Oliveira, J

2002-10-01

The effect of ascorbic acid, light, and storage on the stability of the pigments beta-carotene and capsanthin in red pepper (Capsicum annuum) powder has been elucidated by determining the amount of pigment in samples treated by various concentrations of ascorbic acid. Determination of pigment concentration has been performed after different storage times using high-performance liquid chromatography. The dependence of the concentration of pigments on the concentration of ascorbic acid, presence of light and the storage time has been assessed by stepwise regression analysis. The concentration of pigments decreased at longer storage time and increased at higher concentration of ascorbic acid, beta-carotene being more sensitive towards storage time and concentration of ascorbic acid than capsanthin. Interaction between the effects of light and storage time, and light and concentration of ascorbic acid has been established.

Tree age, fruit size and storage conditions affect levels of ascorbic acid, total phenolic concentrations and total antioxidant activity of 'Kinnow' mandarin juice.

PubMed

Khalid, Samina; Malik, Aman U; Khan, Ahmad S; Shahid, Muhammad; Shafique, Muhammad

2016-03-15

Bioactive compounds (ascorbic acid, total phenolics and total antioxidants) are important constituents of citrus fruit juice; however, information with regard to their concentrations and changes in relation to tree age and storage conditions is limited. 'Kinnow' (Citrus nobilis Lour × Citrus deliciosa Tenora) mandarin juice from fruit of three tree ages (6, 18 and 35 years old) and fruit sizes (large, medium and small) were examined for their bioactive compounds during 7 days under ambient storage conditions (20 ± 2 °C and 60-65% relative humidity (RH)) and during 60 days under cold storage (4 ± 1 °C and 75-80% RH) conditions. Under ambient conditions, a reduction in total phenolic concentrations (TPC) and in total antioxidant activity (TAA) was found for the juice from all tree ages and fruit sizes. Overall, fruit from 18-year-old trees had higher mean TPC (95.86 µg mL(-1) ) and TAA (93.68 mg L(-1) ), as compared to 6 and 35-year-old trees. Likewise, in cold storage, TAA decreased in all fruit size groups from 18 and 35-year-old trees. In all tree age and fruit size groups, TPC decreased initially during 15 days of cold storage and then increased gradually with increase in storage duration. Ascorbic acid concentrations showed an increasing trend in all fruit size groups from 35-year-old trees. Overall, during cold storage, fruit from 18-year-old trees maintained higher mean ascorbic acid (33.05 mg 100 mL(-1) ) concentrations, whereas fruit from 6-year-old trees had higher TAA (153.1 mg L(-1) ) and TPC (115.1 µg mL(-1) ). Large-sized fruit had higher ascorbic acid (32.08 mg 100 mL(-1) ) concentrations and TAA (157.5 mg L(-1) ). Fruit from 18-year-old trees maintained higher TPC and TAA under ambient storage conditions, whereas fruit from 6-year-old trees maintained higher TPC and TAA during cold storage. Small-sized fruit had higher TPC after ambient temperature storage, whereas large fruit size showed higher ascorbic acid concentrations and TAA after cold

Dietary taurine alters ascorbic acid metabolism in rats fed diets containing polychlorinated biphenyls.

PubMed

Mochizuki, H; Oda, H; Yokogoshi, H

2000-04-01

The effect of dietary taurine on ascorbic acid metabolism and hepatic drug-metabolizing enzymes was investigated in rats fed diets containing polychlorinated biphenyls (PCB) to determine whether taurine has an adaptive and protective function in xenobiotic-treated animals. Young male Wistar rats (60 g) were fed diets containing 0 or 0.2 g/kg diet PCB with or without 30 g/kg diet of taurine for 14 d. The rats fed the PCB-containing diets had greater liver weight, higher ascorbic acid concentrations in the liver and spleen and greater hepatic cytochrome P-450 contents than control rats that were not treated with PCB (P < 0.01). In PCB-fed rats, urinary ascorbic acid excretion was enhanced, and serum cholesterol concentration (especially HDL-cholesterol) was significantly elevated compared with those in control rats. Dietary taurine significantly potentiated the increases in the urinary excretion of ascorbic acid and the rise in the levels of cytochrome P-450 which were caused by PCB treatment. On the other hand, the supplementation of taurine to control diet did not alter these variables. Taurine may enhance the hepatic drug-metabolizing systems, leading to the stimulation of the ascorbic acid metabolism in rats fed diets containing PCB.

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

NASA Astrophysics Data System (ADS)

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.

Supplement of a chitosan and ascorbic acid mixture for Crohn's disease: a pilot study.

PubMed

Tsujikawa, Tomoyuki; Kanauchi, Osamu; Andoh, Akira; Saotome, Takao; Sasaki, Masaya; Fujiyama, Yoshihide; Bamba, Tadao

2003-02-01

Although the pathogenesis of Crohn's disease remains unclear, dietary fat is thought to exacerbate intestinal inflammation. Chitosan is a water-insoluble dietary fiber, and a chitosan and ascorbic acid mixture has been shown in rats to increase fecal fat excretion without affecting protein digestibility. However, it remains unclear whether a chitosan and ascorbic acid mixture is safe and effective for patients with Crohn's disease. We designed a pilot trial to investigate the tolerability and amount of fat excretion after the oral administration of a chitosan and ascorbic mixture for inactive Crohn's disease. Eleven outpatients were given seven tablets daily of a chitosan and ascorbic mixture (chitosan was given at 1.05 g/d) for 8 wk. Patients did not interrupt their respective therapies for Crohn's disease. The bowel movements of most patients increased slightly during the study. Nutritional and inflammatory markers in patients did not differ before and after treatment. The chitosan and ascorbic acid mixture significantly increased the fat concentration in the feces during treatment. These results indicated that oral administration of a chitosan and ascorbic acid mixture in patients with Crohn's disease is tolerable and increases fecal fat excretion without affecting disease activity.

Biophysical and computational comparison on the binding affinity of three important nutrients to β-lactoglobulin: folic acid, ascorbic acid and vitamin K3.

PubMed

Shahraki, Somaye; Heydari, Ali; Saeidifar, Maryam; Gomroki, Masoumeh

2017-11-06

Small globular protein, β-lactoglobulin (βLG), which has significant affinity toward many drugs, is the most abundant whey protein in milk. In this study, the interaction of βLG with three important nutrients, ascorbic acid (ASC), folic acid (FOL), and vitamin K3 (VK3) was investigated by spectroscopic methods (UV-visible and fluorescence) along with molecular docking technique. The results of fluorescence measurements showed that studied nutrients strongly quenched βLG fluorescence in static (FOL and ACS) or static-dynamic combined quenching (VK3) mode. The values of binding constants (K βLG-ASC  ~ 4.34 × 10 4  M -1 , K βLG-FOL ~ 1.67 × 10 4  M -1 and K βLG-VK3 ~ 13.49 × 10 4  M -1 at 310 K) suggested that VK3 and FOL had stronger binding affinity toward βLG than ASC. Thermodynamic analysis indicated that hydrophobic interactions are the major forces in the stability of FOL-βLG complex with enthalpy- and entropy-driving mode while, hydrogen bonds and van der Waals interactions play a major role for βLG-ASC and βLG-VK3 associations. The results of 3D fluorescence FT-IR and UV-Visible measurements indicated that the binding of above nutrients to βLG may induce conformational and micro-environmental changes of protein. Also, there is a reciprocal complement between spectroscopic techniques and molecular docking modeling. The docking results indicate that the ASC, FOL, and VK3 bind to residues located in the subdomain B of βLG. Finally, this report suggests that βLG could be used as an effective carrier of above nutrients in functional foods.

Review of high-dose intravenous vitamin C as an anticancer agent.

PubMed

Wilson, Michelle K; Baguley, Bruce C; Wall, Clare; Jameson, Michael B; Findlay, Michael P

2014-03-01

In the 1970s, Pauling and Cameron reported increased survival of patients with advanced cancer treated with high-dose intravenous (IV) vitamin C (L-ascorbate, ascorbic acid). These studies were criticized for their retrospective nature and lack of standardization of key prognostic factors including performance status. Subsequently, several well-designed randomized controlled trials failed to demonstrate a significant survival benefit, although these trials used high-dose oral vitamin C. Marked differences are now recognized in the pharmacokinetics of vitamin C with oral and IV administration, opening the issue of therapeutic efficacy to question. In vitro evidence suggests that vitamin C functions at low concentrations as an antioxidant but may have pro-oxidant activity at high concentrations. The mechanism of its pro-oxidant action is not fully understood, and both intra- and extracellular mechanisms that generate hydrogen peroxide have been proposed. It remains to be proven whether vitamin C-induced reactive oxygen species occur in vivo and, if so, whether this will translate to a clinical benefit. Current clinical evidence for a therapeutic effect of high-dose IV vitamin C is ambiguous, being based on case series. The interpretation and validation of these studies is hindered by limited correlation of plasma vitamin C concentrations with response. The methodology exists to determine if there is a role for high-dose IV vitamin C in the treatment of cancer, but the limited understanding of its pharmacodynamic properties makes this challenging. Currently, the use of high-dose IV vitamin C cannot be recommended outside of a clinical trial. © 2014 Wiley Publishing Asia Pty Ltd.

Guinea pig ascorbate status predicts tetrahydrobiopterin plasma concentration and oxidation ratio in vivo.

PubMed

Mortensen, Alan; Hasselholt, Stine; Tveden-Nyborg, Pernille; Lykkesfeldt, Jens

2013-10-01

Tetrahydrobiopterin (BH₄) is an essential co-factor of nitric oxide synthases and is easily oxidized to dihydrobiopterin (BH₂) which promotes endothelial nitric oxide synthase uncoupling and deleterious superoxide production. Vitamin C has been shown to improve endothelial function by different mechanisms, some involving BH₄. The hypothesis of the present study was that vitamin C status, in particular low levels, influences biopterin redox status in vivo. Like humans, the guinea pig lacks the ability to synthesize vitamin C and was therefore used as model. Seven day old animals (n = 10/group) were given a diet containing 100, 250, 500, 750, 1000, or 1500 ppm vitamin C until euthanasia at age 60-64 days. Blood samples were drawn from the heart and analyzed for ascorbate, dehydroascorbic acid (DHA), BH₄ and BH₂ by high-performance liquid chromatography. Plasma BH₄ levels were found to be significantly lower in animals fed 100 ppm vitamin C compared to all other groups (P < .05 or less). BH₂ levels were not significantly different between groups but the BH₂-to-BH₄ ratio was higher in the group fed 100 ppm vitamin C (P < .001 all cases). Significant positive correlations between BH4 and ascorbate and between BH₂-to-BH₄ ratio and DHA were observed (P < .0001 both cases). Likewise, BH₂-to-BH₄ ratio was negatively correlated with ascorbate (P < .0001) as was BH₄ and DHA (P < .005). In conclusion, the redox status of plasma biopterins, essentially involved in vasodilation, depends on the vitamin C status in vivo. Thus, ingestion of insufficient quantities of vitamin C not only leads to vitamin C deficiency but also to increased BH₄ oxidation which may promote endothelial dysfunction. © 2013 Elsevier Inc. All rights reserved.

Vitamin profile of cooked foods: how healthy is the practice of ready-to-eat foods?

PubMed

Agte, Vaishali; Tarwadi, Kirtan; Mengale, Sangeeta; Hinge, Ashwini; Chiplonkar, Shashi

2002-05-01

During recent years importance of B complex vitamins, beta-carotene and vitamin C has been realised in terms of their antioxidative and anticarcinogenic properties. Fruits and vegetables are the rich sources of these vitamins. However, there are considerable cooking losses of vitamins, and information on vitamin contents of cooked foods is essential for assessing the adequacy of vitamin intakes. Secondly, there is a growing trend to consume ready-to-eat foods such as stuffed pancakes (samosa, patties), pastries, French fries; replacing traditional foods for lunch or dinner like roti, vegetable curry, bread, non-vegetarian items. Ready-to-eat foods are considered to give empty calories rather than a balanced diet. A study was undertaken to estimate ascorbic acid, folic acid, riboflavin, thiamine and beta-carotene of 263 cooked food samples and 260 meals representing dietary patterns of Asia, Africa, Europe, USA and Latin America by spectrophotometry and photoflurometry. A broad range of beta-carotene (84-2038 mcg%), riboflavin (0.01-0.48 mg%), thiamine (0.04-0.36 mg%), vitamin C (1-28 mg%) and folate (26-111 mcg%) was observed in individual foods. Bakery products and sweets were found to be poor sources and green leafy vegetables and fruits were good sources of these five vitamins. The differences between ready-to-eat foods and meals consumed during lunch or dinner were prominent for beta-carotene, ascorbic acid, riboflavin and folic acid (P < 0.05). The cooking losses were 34.6, 30, 52.2, 45.9 and 32.2% in case of ascorbic acid, thiamine, riboflavin, beta-carotene and folic acid respectively. Irrespective of whether it is ready-to-eat or a lunch/dinner food item, the contribution of vegetables in the preparations was found to make a marked impact on the vitamin profile. While results justify the concept of a food pyramid, emphasis needs to be given to types of fruits and vegetables rich in vitamins; preferably in their uncooked form, rather than considering their

Characterization of the radical-scavenging reaction of 2-O-substituted ascorbic acid derivatives, AA-2G, AA-2P, and AA-2S: a kinetic and stoichiometric study.

PubMed

Takebayashi, Jun; Tai, Akihiro; Gohda, Eiichi; Yamamoto, Itaru

2006-04-01

The aim of this study was to characterize the antioxidant activity of three ascorbic acid (AA) derivatives O-substituted at the C-2 position of AA: ascorbic acid 2-glucoside (AA-2G), ascorbic acid 2-phosphate (AA-2P), and ascorbic acid 2-sulfate (AA-2S). The radical-scavenging activities of these AA derivatives and some common low molecular-weight antioxidants such as uric acid or glutathione against 1,1-diphenyl-picrylhydrazyl (DPPH) radical, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS+), or galvinoxyl radical were kinetically and stoichiometrically evaluated under pH-controlled conditions. Those AA derivatives slowly and continuously reacted with DPPH radical and ABTS+, but not with galvinoxyl radical. They effectively reacted with DPPH radical under acidic conditions and with ABTS+ under neutral conditions. In contrast, AA immediately quenched all species of radicals tested at all pH values investigated. The reactivity of Trolox, a water-soluble vitamin E analogue, was comparable to that of AA in terms of kinetics and stoichiometrics. Uric acid and glutathione exhibited long-lasting radical-scavenging activity against these radicals under certain pH conditions. The radical-scavenging profiles of AA derivatives were closer to those of uric acid and glutathione rather than to that of AA. The number of radicals scavenged by one molecule of AA derivatives, uric acid, or glutathione was equal to or greater than that by AA or Trolox under the appropriate conditions. These data suggest the potential usage of AA derivatives as radical scavengers.

Ascorbic Acid Alleviates Water Stress in Young Peach Trees and Improves Their Performance after Rewatering

PubMed Central

Penella, Consuelo; Calatayud, Ángeles; Melgar, Juan C.

2017-01-01

Exogenous application of biochemicals has been found to improve water stress tolerance in herbaceous crops but there are limited studies on deciduous fruit trees. The goal of this research was to study if ascorbic acid applications could improve physiological mechanisms associated with water stress tolerance in young fruit trees. Ascorbic acid was foliarly applied at a concentration of 250 ppm to water-stressed and well-watered peach trees (control) of two cultivars (‘Scarletprince’ and ‘CaroTiger’). Trees received either one or two applications, and 1 week after the second application all trees were rewatered to field capacity. Upon rewatering, CO2 assimilation and stomatal conductance of water-stressed ‘Scarletprince’ trees sprayed with ascorbic acid (one or two applications) were similar to those of well-irrigated trees, but water-stressed trees that had not received ascorbic acid did not recover photosynthetical functions. Also, water status in sprayed water-stressed ‘Scarletprince’ trees was improved to values similar to control trees. On the other hand, water-stressed ‘CaroTiger’ trees needed two applications of ascorbic acid to reach values of CO2 assimilation similar to control trees but these applications did not improve their water status. In general terms, different response mechanisms to cope with water stress in presence of ascorbic acid were found in each cultivar, with ‘Scarletprince’ trees preferentially using proline as compatible solute and ‘CaroTiger’ trees relying on stomatal regulation. The application of ascorbic acid reduced cell membrane damage and increased catalase activity in water-stressed trees of both cultivars. These results suggest that foliar applications of ascorbic acid could be used as a management practice for improving water stress tolerance of young trees under suboptimal water regimes. PMID:28979284