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.

Characterization of keratinocyte differentiation induced by ascorbic acid: protein kinase C involvement and vitamin C homeostasis.

PubMed

Savini, Isabella; Catani, Maria Valeria; Rossi, Antonello; Duranti, Guglielmo; Melino, Gerry; Avigliano, Luciana

2002-02-01

Epidermal keratinocytes undergo differentiation in response to several stimuli to form the cornified envelope, a structure that contributes to the barrier function of skin. Although differentiation has been extensively analyzed, the precise role of vitamin C during this process is still not defined. Ascorbic acid, besides acting as a radical scavenger, has been shown to promote mesenchymal differentiation. In this study, we found that keratinocytes grown in ascorbate-supplemented medium developed a differentiated phenotype, as demonstrated by enhanced expression of marker genes and increase in cornified envelope content. The pro-differentiating effects of ascorbate were mediated by the protein-kinase-C-dependent induction of activating protein 1 DNA binding activity; indeed, down-modulation of protein kinase C activity abolished differentiation triggered by ascorbic acid. Although vitamin C appeared to regulate the same signaling pathway modulated by calcium, a classical in vitro inducer of epidermal differentiation, nonetheless terminally differentiated keratinocytes exhibited different ascorbate homeostasis and cellular antioxidant status. Indeed, we found that, unlike calcium, differentiation promoted by ascorbate was accompanied by (i) an enhanced ascorbate transport, due to overexpression of specific transporters, (ii) a great efficiency of dehydroascorbate uptake, and (iii) an increase in glutathione content with respect to proliferating cells. Ascorbic acid may be useful to promote epidermal differentiation, avoiding depletion of hydrophilic antioxidant stores.

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.

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...

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

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

PubMed

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

2016-04-01

Vitamin C deficiency globally affects several hundred million people and has been associated with increased morbidity and mortality in numerous studies. In this study, bioavailability of the oxidized form of vitamin C (l-dehydroascorbic acid or DHA)-commonly found in vitamin C containing food products prone to oxidation-was studied. Our aim was to compare tissue accumulation of vitamin C in guinea pigs receiving different oral doses of either ascorbate or DHA. In all tissues tested (plasma, liver, spleen, lung, adrenal glands, kidney, muscle, heart, and brain), only sporadic differences in vitamin C accumulation from ascorbate or DHA were observed except for the lowest dose of DHA (0.25mg/ml in the drinking water), where approximately half of the tissues had slightly yet significantly less vitamin C accumulation than from the ascorbate source. As these results contradicted data from rats, we continued to explore the ability to recycle DHA in blood, liver and intestine in guinea pigs, rats and mice. These investigations revealed that guinea pigs have similar recycling capacity in red blood cells as observed in humans, while rats and mice do not have near the same ability to reduce DHA in erythrocytes. In liver and intestinal homogenates, guinea pigs also showed a significantly higher ability to recycle DHA compared to rats and mice. These data demonstrate that DHA in guinea pigs-as in humans-is almost as effective as ascorbate as vitamin C source when it comes to taking up and storing vitamin C and further suggest that the guinea pig is superior to other rodents in modeling human vitamin C homeostasis. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

l-dehydroascorbic acid can substitute l-ascorbic acid as dietary vitamin C source in guinea pigs

PubMed Central

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

2015-01-01

Vitamin C deficiency globally affects several hundred million people and has been associated with increased morbidity and mortality in numerous studies. In this study, bioavailability of the oxidized form of vitamin C (l-dehydroascorbic acid or DHA)—commonly found in vitamin C containing food products prone to oxidation—was studied. Our aim was to compare tissue accumulation of vitamin C in guinea pigs receiving different oral doses of either ascorbate or DHA. In all tissues tested (plasma, liver, spleen, lung, adrenal glands, kidney, muscle, heart, and brain), only sporadic differences in vitamin C accumulation from ascorbate or DHA were observed except for the lowest dose of DHA (0.25 mg/ml in the drinking water), where approximately half of the tissues had slightly yet significantly less vitamin C accumulation than from the ascorbate source. As these results contradicted data from rats, we continued to explore the ability to recycle DHA in blood, liver and intestine in guinea pigs, rats and mice. These investigations revealed that guinea pigs have similar recycling capacity in red blood cells as observed in humans, while rats and mice do not have near the same ability to reduce DHA in erythrocytes. In liver and intestinal homogenates, guinea pigs also showed a significantly higher ability to recycle DHA compared to rats and mice. These data demonstrate that DHA in guinea pigs—as in humans—is almost as effective as ascorbate as vitamin C source when it comes to taking up and storing vitamin C and further suggest that the guinea pig is superior to other rodents in modeling human vitamin C homeostasis. PMID:26609560

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

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.

Effects of ascorbic acid enrichment by immersion of rainbow trout (Oncorhynchus mykiss, Walbaum 1792) eggs and embryos

USGS Publications Warehouse

Falahatkar, B.; Dabrowski, K.; Arslan, M.; Rinchard, J.

2006-01-01

This study was conducted to examine the effects of different forms and concentrations of ascorbic acid (vitamin C), and different enrichment times (24 and 48 h post ovulation) on egg, embryo and alevin ascorbate concentrations and survival of rainbow trout (enrichment was at the ova stage). In experiments 1 and 2, fertilized eggs were immersed in water containing ascorbate at 0 (control), 100, 1000 mg L-1 l-ascorbic acid (AA) and 2000 mg L -1 l-ascorbyl monophosphate (AP). In experiment 3, 0 (control), 500 and 1000 mg L-1 AA neutralized (N) with NaOH, 1000 mg L-1 AA non-neutralized (NN), 1000 and 2000 mg L-1 AP immersions were used. The mean total ascorbic acid (TAA) and dehydroascorbic acid (DHA) concentrations were measured before fertilization, at 3 and 24 h after fertilization, at the eyed stage, and in hatched alevins. We observed significant differences in TAA concentration at different immersion levels at 3 and 24 h after fertilization. Survival decreased significantly depending on the level of vitamin C, pH of the solutions and immersion time. We suggest that when broodstock rainbow trout do not have enough vitamin C in their ovaries, immersion of eggs in 1000 mg L-1 of neutralized AA may be useful. ?? 2006 Blackwell Publishing Ltd.

Sodium-dependent Vitamin C transporter 2 deficiency impairs myelination and remyelination after injury: Roles of collagen and demethylation.

PubMed

Röhr, Dominik; Halfter, Hartmut; Schulz, Jörg B; Young, Peter; Gess, Burkhard

2017-07-01

Peripheral nerve myelination involves rapid production of tightly bound lipid layers requiring cholesterol biosynthesis and myelin protein expression, but also a collagen-containing extracellular matrix providing mechanical stability. In previous studies, we showed a function of ascorbic acid in peripheral nerve myelination and extracellular matrix formation in adult mice. Here, we sought the mechanism of action of ascorbic acid in peripheral nerve myelination using different paradigms of myelination in vivo and in vitro. We found impaired myelination and reduced collagen expression in Sodium-dependent Vitamin C Transporter 2 heterozygous mice (SVCT2 +/- ) during peripheral nerve development and after peripheral nerve injury. In dorsal root ganglion (DRG) explant cultures, hypo-myelination could be rescued by precoating with different collagen types. The activity of the ascorbic acid-dependent demethylating Ten-eleven-translocation (Tet) enzymes was reduced in ascorbic acid deprived and SVCT2 +/- DRG cultures. Further, in ascorbic acid-deprived DRG cultures, methylation of a CpG island in the collagen alpha1 (IV) and alpha2 (IV) bidirectional promoter region was increased compared to wild-type and ascorbic acid treated controls. Taken together, these results provide further evidence for the function of ascorbic acid in myelination and extracellular matrix formation in peripheral nerves and suggest a putative molecular mechanism of ascorbic acid function in Tet-dependent demethylation of collagen promoters. © 2017 Wiley Periodicals, Inc.

Thermal stability of L-ascorbic acid and ascorbic acid oxidase in broccoli (Brassica oleracea var. italica).

PubMed

Munyaka, Ann Wambui; Makule, Edna Edward; Oey, Indrawati; Van Loey, Ann; Hendrickx, Marc

2010-05-01

The thermal stability of vitamin C (including l-ascorbic acid [l-AA] and dehydroascorbic acid [DHAA]) in crushed broccoli was evaluated in the temperature range of 30 to 90 degrees C whereas that of ascorbic acid oxidase (AAO) was evaluated in the temperature range of 20 to 95 degrees C. Thermal treatments (for 15 min) of crushed broccoli at 30 to 60 degrees C resulted in conversion of l-AA to DHAA whereas treatments at 70 to 90 degrees C retained vitamin C as l-AA. These observations indicated that enzymes (for example, AAO) could play a major role in the initial phase (that is, oxidation of l-AA to DHAA) of vitamin C degradation in broccoli. Consequently, a study to evaluate the temperature-time conditions that could result in AAO inactivation in broccoli was carried out. In this study, higher AAO activity was observed in broccoli florets than stalks. During thermal treatments for 10 min, AAO in broccoli florets and stalks was stable until around 50 degrees C. A 10-min thermal treatment at 80 degrees C almost completely inactivated AAO in broccoli. AAO inactivation followed 1st order kinetics in the temperature range of 55 to 65 degrees C. Based on this study, a thermal treatment above 70 degrees C is recommended for crushed vegetable products to prevent oxidation of l-AA to DHAA, the onset of vitamin C degradation. The results reported in this study are applicable for both domestic and industrial processing of vegetables into products such as juices, soups, and purees. In this report, we have demonstrated that processing crushed broccoli in a temperature range of 30 to 60 degrees C could result in the conversion of l-ascorbic acid to dehydroascorbic (DHAA), a very important reaction in regard to vitamin C degradation because DHAA could be easily converted to other compounds that do not have the biological activity of vitamin C.

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.

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.

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.

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

PubMed

Pappenberger, Günter; Hohmann, Hans-Peter

2014-01-01

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

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

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

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

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.

Ascorbic Acid

MedlinePlus

C-500® Chewable Tablet ... C-Time® ... Centrum® Singles-Vitamin C ... Sunkist® Vitamin C ... Vicks® Vitamin C Drops ... a disease caused by a lack of vitamin C in the body.This medication is sometimes prescribed ...

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.

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.

Vitamin C Content of Commercial Orange Juices

ERIC Educational Resources Information Center

Haddad, Paul

1977-01-01

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

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.

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

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 total consumption.

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.

[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.

New evidence for antioxidant properties of vitamin C.

PubMed

Vojdani, A; Bazargan, M; Vojdani, E; Wright, J

2000-01-01

This study was designed to examine the effect of 500 to 5,000 mg of ascorbic acid on DNA adducts, natural killer (NK) cell activity, programmed cell death, and cell cycle analysis of human peripheral blood leukocytes. According to our hypothesis, if ascorbic acid is a pro-oxidant, doses between 500 and 5,000 mg should enhance DNA adduct formation, decrease immune function, change the cell cycle progression, and increase the rate of apoptosis. Twenty healthy volunteers were divided into four groups and given either placebo or daily doses of 500, 1,000 or 5,000 mg of ascorbic acid for a period of 2 weeks. On days 0, 1, 7, 15, and 21, blood was drawn from them, and the leukocytes were separated and examined for intracellular levels of ascorbic acid, the level of 8-hydroxyguanosine, NK cell activity, cell cycle progression, and apoptosis. Depending on the subjects, between a 0% and a 40% increase in cellular absorption of ascorbic acid was observed when daily doses of 500 mg were used. At doses greater than 500 mg, this cellular absorption was not increased further, and all doses produced equivalent increases in ascorbic acid on days 1 to 15. This increase in cellular concentration of ascorbic acid resulted in no statistically meaningful changes in the level of 8-hydroxyguanosine, increased NK cytotoxic activity, a reduced percentage of cells undergoing apoptosis, and switched cell cycle phases from S and G2/M to G0/G1. After a period of 1 week, with no placebo or vitamin washout, ascorbic acid levels along with functional assays returned to the baseline and became equivalent to placebos. In comparison with baseline values, no change (not more than daily assays variation) was seen in ascorbate concentrations or other assays during oral placebo treatment. We concluded that ascorbic acid is an antioxidant and that doses up to 5,000 mg neither induce mutagenic lesions nor have negative effects on NK cell activity, apoptosis, or cell cycle.

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.

The importance of vitamin C for hydroxylation of vitamin D3 to 1,25(OH)2D3 in man.

PubMed

Cantatore, F P; Loperfido, M C; Magli, D M; Mancini, L; Carrozzo, M

1991-06-01

The effects of vitamin C on 1,25(OH)2D3 synthesis in humans were evaluated; the study included 20 females. They were divided into 2 groups. The first of the 10 subjects (age range 55-71) received ascorbic acid at a dose of 150 mg/die i.v. for 10 days; the second 10 subjects (age range 55-69) received a placebo i.v. for 10 days. In a later study (after a 30-day washout) the same two groups were tested for the second time with ascorbic acid at a dose of 1,000 mg/die i.v. for 10 days and placebo i.v. for 10 days. Serum calcium and phosphorus, serum Ca++, serum proteins, blood and urinary pH, serum 25(OH)D3 and 1,25(OH)2D3, serum PTH, urinary hydroxyprolin were tested before and after the treatments. In the first study a significant increase in serum 1,25(OH)2D3 was observed after ascorbic acid while no significant variation was observed for the other parameters. In the second study, a significant increase in serum Ca++ and a significant decrease in serum 1,25(OH)2D3 were observed after ascorbic acid while no significant variation was observed for the other parameters. The authors conclude that ascorbic acid promotes 1,25(OH)2D3 synthesis at a paraphysiologic dose (150 mg/die) in humans but this synthesis is inhibited at higher doses (1,000 mg/die). The latter effect by Ca++ or by an effect of ascorbate on 1 alpha-hydroxylase enzyme could be mediated.

An evaluation of the antiaging properties of strawberry hydrolysate treatment enriched with L-ascorbic acid applied with microneedle mesotherapy.

PubMed

Markiewicz, Agata; Zasada, Malwina; Erkiert-Polguj, Anna; Wieckowska-Szakiel, Marzena; Budzisz, Elzbieta

2018-04-16

Mature skin is characterized by a loss of elasticity, hyperpigmentation, and dehydration. L-ascorbic acid stimulates the synthesis of collagen type I, inhibits melanogenesis, and helps to maintain correct skin hydration. Combining microneedle mesotherapy with the application of preparations rich in vitamin C results in better therapeutic effects due to the improved absorption of active substances. The study evaluates the effectiveness of the application of strawberry hydrolysate enriched with L-ascorbic acid using microneedle mesotherapy. Seventeen volunteers aged 45-70 years underwent a series of four microneedle mesotherapy treatments with vitamin C serum, performed every 10 days. The 20% L-ascorbic acid solution (pH = 3.5) was prepared immediately before application. After the treatment, the participants gave a subjective assessment of the effectiveness. Cutometer ® was used to measure skin elasticity and firmness, Corneometer ® to measure skin hydration, and Mexameter ® skin tone. The results of the survey showed improvements in skin hydration and elasticity. In vivo studies confirmed the effectiveness of serum and the impact of the active substance on skin firmness and elasticity, the degree of hydration and skin tone. Microneedling with vitamin C improves skin tone, hydratation and firmness, and decreases the visibility of hyperpigmentation. © 2018 Wiley Periodicals, Inc.

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.

[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.

Electrospray ionization mass spectrometric investigations of [alpha]-dicarbonyl compounds--Probing intermediates formed in the course of the nonenzymatic browning reaction of l-ascorbic acid

NASA Astrophysics Data System (ADS)

Schulz, Anke; Trage, Claudia; Schwarz, Helmut; Kroh, Lothar W.

2007-05-01

A new method is presented which allows the simultaneous detection of various [alpha]-dicarbonyl compounds generated in the course of the nonenzymatic browning reaction initiated by thermal treatment of l-ascorbic acid, namely: glyoxal, methylglyoxal, diacetyl, 3-deoxy-l-pentosone, and l-threosoneE 3-Deoxy-l-threosone was successfully identified as a new C4-[alpha]-dicarbonyl structure for the first time in the degradation of Vitamin C by application of this non-chromatographic mass spectrometric approach. Moreover, a more detailed elucidation of the mechanistic scenario with respect to the oxidative and nonoxidative pathways is presented by using dehydro-l-ascorbic acid and 2,3-diketo-l-gulonic acid instead of l-ascorbic acid as a starting material. Furthermore, the postulated pathways are corroborated with the aid of 13C-isotopic labeling studies. The investigations were extended to baby food, and the successful detection of [alpha]-dicarbonyl compounds characteristic for Vitamin C degradation proved the matrix tolerance of the introduced method.

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 experiment with Vibrio harveyi showed that lower cumulative survival was in fish fed the unsupplemented diet, the cumulative survival were significantly increased with increase of the dietary ascorbic acid levels from 13.6 to 96.6 mg kg(-1), while the cumulative survival reached plateau when dietary ascorbic acid levels increased from 96.6 to 386.5 mg kg(-1). These results indicated that dietary vitamin C did significantly influence on growth performance and immune response of juvenile cobia. 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.

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.

Pulmonary bioavailability of ascorbic acid in an ascorbate-synthesising species, the horse.

PubMed

Deaton, Christopher M; Marlin, David J; Smith, Nicola C; Roberts, Colin A; Harris, Pat A; Kelly, Frank J; Schroter, Robert C

2003-04-01

Vitamin C (ascorbic acid) is a non-enzymatic antioxidant important in protecting the lung against oxidative damage and is decreased in lung lining fluid of horses with airway inflammation. To examine possible therapeutic regimens in a species with ascorbate-synthesising capacity, we studied the effects of oral supplementation of two forms of ascorbic acid, (each equivalent to 20 mg ascorbic acid per kg body weight) on the pulmonary and systemic antioxidant status of six healthy ponies in a 3 x 3 Latin square design. Two weeks supplementation with ascorbyl palmitate significantly increased mean plasma ascorbic acid concentrations compared to control (29 +/- 5 and 18 +/- 7 micromol/l, respectively; p < 0.05). Calcium ascorbyl-2-monophosphate, a more stable form of ascorbic acid, also increased mean plasma ascorbic acid concentrations, but not significantly (23 +/- 1 micromol/l; p = 0.07). The concentration of ascorbic acid in bronchoalveolar lavage fluid increased in five out of six ponies following supplementation with either ascorbyl palmitate or calcium ascorbyl-2-monophosphate compared with control (30 +/- 10, 25 +/- 4 and 18 +/- 8 micromol/l, respectively; p < 0.01). Neither supplement altered the concentration of glutathione, uric acid or alpha-tocopherol in plasma or bronchoalveolar lavage fluid. In conclusion, the concentration of lung lining fluid ascorbic acid is increased following ascorbic acid supplementation (20 mg/kg body weight) in an ascorbate-synthesising species.

Vitamin C-lipid metabolites: uptake and retention and effect on plasma C-reactive protein and oxidized LDL levels in healthy volunteers.

PubMed

Pancorbo, Dario; Vazquez, Carlos; Fletcher, Mary Ann

2008-11-01

Previously, a novel formulation of vitamin C-lipid metabolites (PureWay-C) was shown to be more rapidly taken-up by human T-lymphocytes and more rapidly stimulate neurite outgrowth, fibroblast adhesion and inhibition of xenobiotic-induced T-cell hyperactivation. Here, PureWay-C serum levels were measured in healthy volunteers after oral supplementation. Plasma C-reactive protein and oxidized low density lipoprotein levels (LDL) were also measured. Healthy volunteers maintained a low vitamin C diet for 14 days and, following an overnight fast, received a single oral dose of (vitamin C) 1000 mg of either ascorbic acid (AA), calcium ascorbate (CaA), vitamin C-lipid metabolites (PureWay-C), or calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C). Blood samples were collected immediately prior to the oral dose administration and at various times post ingestion. Twenty-four-hour urine collections were saved for oxalate and uric acid assays. PureWay-C supplementation leads to the highest absolute serum vitamin C levels when compared to AA, CaA and Ester-C. PureWay-C provides a statistically significant greater serum level than calcium ascorbate at 1, 2, 4, and 6 hours post oral supplementation whereas Ester-C shows a less but slightly statistically significant increase at only 1 and 4 hours. Oral supplementation with PureWay-C also led to a greater reduction in plasma C-reactive protein and oxidized LDL levels compared to the other vitamin C formulations. PureWay-C is more rapidly absorbed and leads to higher serum vitamin C levels and greater reduction of plasma levels of inflammatory and oxidative stress markers than other forms of vitamin C, including Ester-C.

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.

Studies on the excretion of ascorbic acid 2-sulfate and total vitamin C into human urine after oral administration of ascorbic acid 2-sulfate.

PubMed

Tsujimura, M; Fukuda, T; Kasai, T

1982-10-01

The excretion of AsS and total vitamin C into urine after oral administration of AsS to humans was investigated. When 10 mmol of AsS was administered to the subjects, the excretion of AsS into urine continued for 60 hr in males and 48 hr in females. The average amount excreted per hour was less than 5 mg. These results differed from those for AsA and DAsA orally administered to humans. The determination of vitamin C after oral administration of AsS to the subjects consisting of ten males and six females showed no vitamin C effect in humans, similarly to the case with the guinea pig and the rhesus monkey.

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

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.

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.

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.

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.

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

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.

[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.

Morphological Diversity in Crystal Growth of l-Ascorbic Acid Dissolved in Methanol

NASA Astrophysics Data System (ADS)

Ito, Miho; Izui, Machiko; Yamazaki, Yoshihiro; Matsushita, Mitsugu

2003-06-01

Morphological diagram with respect to crystal growth of l-ascorbic acid (C6H8O6; so-called vitamin C) from methanol solution on a flat glass dish is presented. Varying humidity and initial concentration of l-ascorbic acid in methanol solution, the following three distinct kinds of growing patterns have been observed: homogeneous disk, concentric ring and dendrite. In addition, in higher concentration clearly faceted small single crystals grow in any humidity less than 90%. Crossovers from one pattern to another were observed, too.

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.

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...

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

ERIC Educational Resources Information Center

King, David; Friend, Jeffrey; Kariuki, James

2010-01-01

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

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...

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.

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.

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.

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.

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.

21 CFR 172.135 - Disodium EDTA.

Code of Federal Regulations, 2014 CFR

2014-04-01

... levels prescribed, calculated as anhydrous calcium disodium EDTA: Food Limitation (parts per million) Use Aqueous multivitamin preparations 150 With iron salts as a stabilizer for vitamin B 12 in liquid... accelerator with sodium ascorbate or ascorbic acid. Dressings, nonstandardized 75 Preservative. French...

Sequential injection redox or acid-base titration for determination of ascorbic acid or acetic acid.

PubMed

Lenghor, Narong; Jakmunee, Jaroon; Vilen, Michael; Sara, Rolf; Christian, Gary D; Grudpan, Kate

2002-12-06

Two sequential injection titration systems with spectrophotometric detection have been developed. The first system for determination of ascorbic acid was based on redox reaction between ascorbic acid and permanganate in an acidic medium and lead to a decrease in color intensity of permanganate, monitored at 525 nm. A linear dependence of peak area obtained with ascorbic acid concentration up to 1200 mg l(-1) was achieved. The relative standard deviation for 11 replicate determinations of 400 mg l(-1) ascorbic acid was 2.9%. The second system, for acetic acid determination, was based on acid-base titration of acetic acid with sodium hydroxide using phenolphthalein as an indicator. The decrease in color intensity of the indicator was proportional to the acid content. A linear calibration graph in the range of 2-8% w v(-1) of acetic acid with a relative standard deviation of 4.8% (5.0% w v(-1) acetic acid, n=11) was obtained. Sample throughputs of 60 h(-1) were achieved for both systems. The systems were successfully applied for the assays of ascorbic acid in vitamin C tablets and acetic acid content in vinegars, respectively.

Vitamin C modulates glutamate transport and NMDA receptor function in the retina.

PubMed

Domith, Ivan; Socodato, Renato; Portugal, Camila C; Munis, Andressa F; Duarte-Silva, Aline T; Paes-de-Carvalho, Roberto

2018-02-01

Vitamin C (in the reduced form ascorbate or in the oxidized form dehydroascorbate) is implicated in signaling events throughout the central nervous system (CNS). In the retina, a high-affinity transport system for ascorbate has been described and glutamatergic signaling has been reported to control ascorbate release. Here, we investigated the modulatory role played by vitamin C upon glutamate uptake and N-methyl-d-aspartate (NMDA) receptor activation in cultured retinal cells or in intact retinal tissue using biochemical and imaging techniques. We show that both forms of vitamin C, ascorbate or dehydroascorbate, promote an accumulation of extracellular glutamate by a mechanism involving the inhibition of glutamate uptake. This inhibition correlates with the finding that ascorbate promotes a decrease in cell surface levels of the neuronal glutamate transporter excitatory amino acid transporter 3 in retinal neuronal cultures. Interestingly, vitamin C is prone to increase the activity of NMDA receptors but also promotes a decrease in glutamate-stimulated [ 3 H] MK801 binding and decreases cell membrane content of NMDA receptor glutamate ionotropic receptor subunit 1 (GluN1) subunits. Both compounds were also able to increase cAMP response element-binding protein phosphorylation in neuronal nuclei in a glutamate receptor and calcium/calmodulin kinase-dependent manner. Moreover, the effect of ascorbate is not blocked by sulfinpyrazone and then does not depend on its uptake by retinal cells. Overall, these data indicate a novel molecular and functional target for vitamin C impacting on glutamate signaling in retinal neurons. © 2017 International Society for Neurochemistry.

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

Summary of Operational Rations

DTIC Science & Technology

1982-06-01

fortification of instant coffee with ascorbic acid; of cocoa beverag.e powder and enriched sweet chocolate with vitamin A, ascorbic acid, thiamin and...and ice cream mix Staples such as flour, sugar, rice, macaroni, and shortening Instant puddings Salt, pepper, and other spices 14 MEAL, COMBAT...Turkey Loaf Fruit, Enriched Sweet Chocolate, Crackers, and Cheese Spread *All menus include instant coffee, dry, nondairy cream substitute

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.

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.

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).

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 of mineralized tissue was significantly greater than in ascorbate-treated cultures, but was less than that observed in cultures treated with metabolite-supplemented ascorbate. In vitro treatment with ascorbate containing vitamin C metabolites enhanced the formation of mineralized nodules and collagenous proteins. Calcium threonate may be one of the metabolites influencing the mineralization process. Identifying factors which facilitate the formation of mineralized tissue has significant clinical ramifications in terms of wound healing and bone regeneration.

[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.

[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.

21 CFR 172.135 - Disodium EDTA.

Code of Federal Regulations, 2012 CFR

2012-04-01

... following foods at not to exceed the levels prescribed, calculated as anhydrous calcium disodium EDTA: Food... vitamin B 12 in liquid multivitamin preparations. Canned black-eyed peas 145 Promote color retention... sausage 36 As a cure accelerator with sodium ascorbate or ascorbic acid. Dressings, nonstandardized 75...

21 CFR 172.135 - Disodium EDTA.

Code of Federal Regulations, 2013 CFR

2013-04-01

... following foods at not to exceed the levels prescribed, calculated as anhydrous calcium disodium EDTA: Food... vitamin B 12 in liquid multivitamin preparations. Canned black-eyed peas 145 Promote color retention... sausage 36 As a cure accelerator with sodium ascorbate or ascorbic acid. Dressings, nonstandardized 75...

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.

Structural Requirements of Alkylglyceryl-l-Ascorbic Acid Derivatives for Melanogenesis Inhibitory Activity.

PubMed

Taira, Norihisa; Katsuyama, Yushi; Yoshioka, Masato; Muraoka, Osamu; Morikawa, Toshio

2018-04-10

l-Ascorbic acid has multifunctional benefits on skin aesthetics, including inhibition of melanin production, and is widely used in cosmetics. It, however, has low stability and poor skin penetration. We hypothesize that alkylglyceryl-l-ascorbic acid derivatives, highly stable vitamin C-alkylglycerol conjugates, would have similar anti-melanogenic activity with better stability and penetration. We test 28 alkylglyceryl-l-ascorbic acid derivatives ( 1 - 28 ) on theophylline-stimulated B16 melanoma 4A5 cells to determine if they inhibit melanogenesis and establish any structure-function relationships. Although not the most potent inhibitors, 3- O -(2,3-dihydroxypropyl)-2- O -hexyl-l-ascorbic acid ( 6 , IC 50 = 81.4 µM) and 2- O -(2,3-dihydroxypropyl)-3- O -hexyl-l-ascorbic acid ( 20 , IC 50 = 117 µM) are deemed the best candidate derivatives based on their inhibitory activities and low toxicities. These derivatives are also found to be more stable than l-ascorbic acid and to have favorable characteristics for skin penetration. The following structural requirements for inhibitory activity of alkylglyceryl-l-ascorbic acid derivatives are also determined: (i) alkylation of glyceryl-l-ascorbic acid is essential for inhibitory activity; (ii) the 3- O -alkyl-derivatives ( 2 - 14 ) exhibit stronger inhibitory activity than the corresponding 2- O -alkyl-derivatives ( 16 - 28 ); and (iii) derivatives with longer alkyl chains have stronger inhibitory activities. Mechanistically, our studies suggest that l-ascorbic acid derivatives exert their effects by suppressing the mRNA expression of tyrosinase and tyrosine-related protein-1.

Degradation of vitamin C by low-energy electrons

NASA Astrophysics Data System (ADS)

Abdoul-Carime, Hassan; Illenberger, Eugen

2004-06-01

We report on the degradation of gas phase vitamin C (ascorbic acid, AA) induced by low-energy electrons. In the energy range of (0-12) eV, different negatively charged fragments, attributed to the dehydro-ascorbic acid anion ((AA-H) -), OH -, O - and H -, are observed. The yield functions indicate that these ions are formed via dissociative electron attachment, DEA. While the formation of (AA-H) - is exclusively observed at sub-excitation energies (<1.5 eV), the other fragments arise from resonance features at higher energies. Possible implications of these observations for radiation damage and food treatment by high energy radiation are considered.

Beyond the antioxidant: the double life of vitamin C.

PubMed

De Tullio, Mario C

2012-01-01

When considering the history of vitamin C, and the names given to this molecule in early days, the Latin proverb nomen est omen suddenly comes to mind. Around 1920, when Casimir Funk introduced the term Vitamin C to indicate the nutritional factor necessary to prevent the pathological state known as scurvy, the nature of the active molecule was still unknown (Davies MB, Austin J, Partridge DA (1991) Vitamin C: Its chemistry and biochemistry. The Royal Society of Chemistry, Cambridge UK). Almost in the same years, Albert Szent-Giörgyi was striving to identify a new 6-carbon sugar he had obtained in crystal form from oranges, lemons, cabbage and adrenal glands. As humorously described by Szent-Giörgyi himself (Szent-Giörgyi A (1963) Lost in the twentieth century. Annu Rev Biochem 36:1-15), he intended to name this yet unknown carbohydrate "ignose". When this name was rejected by Sir Arthur Harden, editor of the Biochemical Journal, he suggested to name it "godnose", meaning that only God could know the real identity of the molecule. Obviously, also this choice was considered inappropriate by Harden, who suggested the plain name "hexuronic acid". Only later, when the structure of "hexuronic acid" had been completely elucidated, and biological tests performed by Swirbely identified this molecule as the anti-scurvy factor vitamin C, Szent-Giörgyi and Walter Norman Haworth decided to eventually name it ascorbic acid (Szent-Giörgyi A (1963) Lost in the twentieth century. Annu Rev Biochem 36:1-15). "Ascorbic" literally means "against scurvy", and scurvy is known to be mainly due to the inactivation of some important dioxygenases involved in the synthesis of a few key molecules, including different collagen forms (De Tullio MC (2004) How does ascorbic acid prevent scurvy? A survey of the nonantioxidant functions of vitamin C. In: Asard H, May J, Smirnoff N (eds) Vitamin C, its functions and biochemistry in animals and plants. Bios Scientific Publishers, Oxford, UK, pp. 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.

Are Recommended Daily Allowances for Vitamin C Adequate?

PubMed Central

Pauling, Linus

1974-01-01

The Recommended Dietary Allowance of vitamin C (ascorbic acid) for adults has now been set at 45 mg day-1 by the U.S. Food and Nutrition Board. This intake suffices to prevent scurvy in most people. It is, however, much less than the optimum intake, the intake that leads to the best of health. A larger intake decreases the incidence and severity of the common cold and other diseases. Ascorbic acid has antiviral and antibacterial activity and is required for phagocytic activity of leukocytes. Several arguments indicate that for different human beings the optimum intake lies between 250 mg day-1 and a much higher value, 5000 mg day-1 or more. It is proposed that the present Recommended Dietary Allowance of 45 mg day-1 of vitamin C for adults be renamed the Minimum Dietary Allowance, defined as the amount needed to prevent scurvy, and that, after consideration of the evidence about intake and the best of health, there be formulated another category of values, the Recommended Daily Intake, with the suggested range of 250 mg day-1 to 4000 mg day-1 of ascorbic acid for an adult. PMID:4612519

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.

Oxidative stability and sensory and functional properties of eggs from laying hens fed supranutritional doses of vitamins E and C.

PubMed

Franchini, A; Sirri, F; Tallarico, N; Minelli, G; Iaffaldano, N; Meluzzi, A

2002-11-01

This study evaluated the effects of two dietary doses of vitamins E and C supplemented separately and together, on the content of vitamin E in the yolk, on the lipid stability of fresh and stored eggs, and on their sensory and functional properties. Hy-Line Brown hens (n = 216) received a basal diet for 8 wk supplemented with 100 or 200 mg DL-alpha-tocopheryl acetate (E100 or E200, respectively)/kg, 500 or 1,000 mg ascorbic acid (C500 and C1000, respectively)/kg, or 100 mg DL-alpha-tocopheryl acetate plus 500 mg ascorbic acid (E100+C500)/kg, whereas the control group received no supplementation. Fresh eggs and eggs stored 30,60, and 90 d at 4 C or stored 28 d at room temperature were analyzed for vitamin E content and TBA-reactive substances (TBARS). We also evaluated functional properties of fresh and cooked eggs and sensory properties of boiled and scrambled eggs. The yolk content of vitamin E depended on the level of dietary addition and decreased after 90 d of storage at 4 C or after 28 d at 25 C. Vitamin supplementation had no effect on fresh or refrigerated eggs, whereas 4 wk of storage at room temperature increased TBARS in the control and the group supplemented with the highest doses of vitamins. Ascorbic acid improved Haugh units and elasticity of albumen gels, whereas cohesiveness and hardness of yolk, albumen and whole-egg gels were not affected by dietary treatment. Panelists were not able to distinguish treated eggs from control eggs.

Determination of the Effect of Various Modes of Cooking on the Vitamin C Content of a Common Food, Green Pepper: An Introductory Biochemistry Experiment.

ERIC Educational Resources Information Center

Johnson, Eric R.

1988-01-01

Describes a laboratory experiment that measures the amount of ascorbic acid destroyed by food preparation methods (boiling and steaming). Points out that aqueous extracts of cooked green pepper samples can be analyzed for ascorbic acid by a relatively simple redox titration. Lists experimental procedure for four methods of preparation. (MVL)

[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.

Requirement of vitamin C for cartilage calcification in a differentiating chick limb-bud mesenchymal cell culture.

PubMed

Boskey, A L; Stiner, D; Doty, S B; Binderman, I

1991-01-01

Mesenchymal cells isolated from stage 21-24 chick limb-buds plated in a micro-mass culture differentiate to form chondrocytes and synthesize a calcifiable matrix. In the presence of inorganic phosphate (4 mM), hydroxyapatite mineral deposits around cartilage nodules. Ascorbic acid is, in general, an essential co-factor for extracellular matrix synthesis in culture, since it is required for collagen synthesis. In this study we demonstrate that in the absence of ascorbic acid supplementation in the mesenchymal cell cultures, mineral deposition (indicated by X-ray diffraction, measurement of Ca:hydroxyproline ratio, and 45Ca uptake) does not occur. Concentrations of 10-50 micrograms/ml ascorbate were compared to find the "optimal" concentration for cell mediated mineralization; 25 micrograms/ml was selected as optimal based on matrix appearance at the EM level and the rate of 45Ca uptake. High concentrations of ascorbic acid (greater than 75 micrograms/ml), while increasing the amount of hydroxyproline in the matrix synthesized, caused some cell death and hence less cell-mediated mineralization. This study demonstrates both the need for viable cells and a proper matrix for in vitro cell-mediated mineralization, and shows that varying the concentration of L-ascorbate (vitamin C) in the medium can have a marked effect on mineralization in vitro.

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.

Organic molecules and nanoparticles in inorganic crystals: Vitamin C in CaCO3 as an ultraviolet absorber

NASA Astrophysics Data System (ADS)

Sato, H.; Ikeya, M.

2004-03-01

Organic molecules and nanoparticles embedded in inorganic crystalline lattices have been studied to add different properties and functions to composite materials. Calcium carbonate was precipitated by dropping an aqueous solution of CaCl2 into that of Na2CO3 containing dissolved vitamin C (ascorbic acid). The optical absorption ascribed to divalent ascorbate anions in the lattice was observed in the ultraviolet B (wavelength: 280-315 nm) region, while solid vitamin C exhibited absorption in the ultraviolet C (100-280 nm) region. The divalent ascorbate anion is only stable in CaCO3 due to the absence of oxygen molecules. Doping CaCO3 with nanoparticles of ZnO also enhanced the absorption in the ultraviolet A (315-380 nm) region. These composite materials are suggested for use as UV absorbers.

Vitamin C for stabilising biological lasers (Conference Presentation)

NASA Astrophysics Data System (ADS)

Kar, Ajoy K.; Mackenzie, Mark D.; Cialowicz, Katarzyna I.; Saleeb, Rebecca S.; Duncan, Rory R.

2016-04-01

We report on efforts to improve the lifetime of biological lasers through the use of ascorbic acid (also commonly known as vitamin C). Fluorescent proteins and dyes, used in biological lasers, suffer from photobleaching due to the build-up of reactive oxygen species (ROS) which causes damage leading to a decrease in emission over time. This is an issue both for laser lifetime and cell health. It has previously been shown that ascorbic acid can be effective in reducing ROS levels in a variety of applications. For our experiments human embryonic kidney cells (HEK293), containing the fluorescent dye Calcein AM, were placed between two dielectric plane mirrors to form a laser cavity. The cells were pumped using the output of a Ti:Sapphire femtosecond OPO system, frequency doubled twice in BBO crystals, giving an output of 474 nm. Initial results have shown an increase in laser lifetime when ascorbic acid is added to cells indicating a reduction in the build-up of ROS.

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, 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 adjuvant cancer therapy remains under investigated. While AA and A2P were capable of modulating HIF-1α protein accumulation/activity, DHA supplementation resulted in minimal intracellular vitamin C activity with decreased ability to inhibit HIF-1α activity and malignant potential in advanced melanoma. Restoring AA dependent regulation of HIF-1α in malignant cells may prove beneficial in reducing chemotherapy resistance and improving treatment outcomes. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

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.

Absorption rates and free radical scavenging values of vitamin C-lipid metabolites in human lymphoblastic cells.

PubMed

Weeks, Benjamin S; Perez, Pedro P

2007-10-01

In this study we investigated the cellular absorption rates, antioxidant and free radical scavenging activity of vitamin C-lipid metabolites. The absorption was measured in a human lymphoblastic cell line using a spectrophotometric technique. Cellular vitamin C levels in the human lymphoblastic H9 cell line were measured using the 2,4-dinitrophenylhydrazine spectrophotometric technique. Free radical scavenging activity of vitamin C-lipid metabolites was measured by the reduction of 1,1-diphenyl-2-picryl hydrazyl (DPPH) to 1,1-diphenyl-2-picryl hydrazine. Vitamin C-lipid metabolite scavenging of peroxyl radical oxygen reactive species (ORAC) was determined by fluorescence spectrophotometry. Compared to ascorbic acid (AA), calcium ascorbate (CaA), and calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C), vitamin C-lipid metabolites (PureWay-C) were more rapidly absorbed by the H9 human T-lymphocytes. The vitamin C-lipid metabolites (PureWay-C) also reduced pesticide-induced T-lymphocyte aggregation by 84%, while calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C) reduced aggregation by only 34%. The vitamin C-lipid metabolites (PureWay-C) demonstrated free radical scavenging activity of nearly 100% reduction of DPPH at 20 microg/ml and oxygen radical scavenging of over 1200 micro Trolox equivalents per gram. These data demonstrate that the vitamin C-lipid metabolites (PureWay-C) are more rapidly taken-up and absorbed by cells than other forms of vitamin C, including Ester-C. This increased rate of absorption correlates with an increased protection of the T-lymphocytes from pesticide toxicities. Further, vitamin C-lipid metabolites (PureWay-C) are a potent antioxidant and have significant free radical scavenging capabilities.

Antioxidant properties of selected fruit cultivars grown in Sri Lanka.

PubMed

Silva, K D R R; Sirasa, M S F

2018-01-01

Extracts of twenty locally available Sri Lankan fruits were analysed for 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, ferrous reducing antioxidant power (FRAP), total phenolic content (TPC), total flavonoid content (TFC) and vitamin C content. The results showed that gooseberry (Phyllanthus emblica 'local') exhibited the highest DPPH scavenging activity (111.25mg ascorbic acid equivalent antioxidant capacity (AEAC)/g), FRAP (1022.05μmol FeSO 4 /g), TPC (915.7mg gallic acid equivalents (GAE)/100g), TFC (873.2mg catechin equivalents (CE)/100g) and vitamin C (136.8mg ascorbic acid equivalents (AAE)/100g), respectively. Sugar apple (Annona squamosa 'local') and star fruit (Averrhoa carambola 'Honey Sweet') obtained the second and third highest antioxidant activities in terms of rankings of FRAP, DPPH activities, TPC, TFC and vitamin C content. Strong correlation between vitamin C, TPC and TFC with FRAP and DPPH showed their contribution to antioxidant capacity. Among the selected fruits, underutilized fruit cultivar gooseberry showed the highest overall antioxidant potential. Copyright © 2016 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.

Transfering vitamin C from fish to embryos

USDA-ARS?s Scientific Manuscript database

Beneficial effects of ascorbic acid supplementation to broodstock of a select aquaculture species is well documented. At the present levels of feeding, dietary means of vitamin C does not meet the requirements for maturation, reproduction and needs of early life stages of larvae. In addition, thi...

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.

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.

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

The Vitamin C Clock Reaction.

ERIC Educational Resources Information Center

Wright, Stephen W.

2002-01-01

Describes an iodine clock reaction that produces an effect similar to the Landolt clock reaction. This reaction uses supermarket chemicals and avoids iodate, bisulfite, and mercury compounds. Ascorbic acid and tincture of iodine are the main reactants with alternate procedures provided for vitamin C tablets and orange juice. (DDR)

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.

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

[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.

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...

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.

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.

Comparative study on the inhibitory effects of antioxidant vitamins and radon on carbon tetrachloride-induced hepatopathy.

PubMed

Kataoka, Takahiro; Nishiyama, Yuichi; Yamato, Keiko; Teraoka, Junichi; Morii, Yuji; Sakoda, Akihiro; Ishimori, Yuu; Taguchi, Takehito; Yamaoka, Kiyonori

2012-11-01

We have previously reported that radon inhalation activates anti-oxidative functions and inhibits carbon tetrachloride (CCl(4))-induced hepatopathy. It has also been reported that antioxidant vitamins can inhibit CCl(4)-induced hepatopathy. In the current study, we examined the comparative efficacy of treatment with radon, ascorbic acid and α-tocopherol on CCl(4)-induced hepatopathy. Mice were subjected to intraperitoneal injection of CCl(4) after inhaling approximately 1000 or 2000 Bq/m(3) radon for 24 h, or immediately after intraperitoneal injection of ascorbic acid (100, 300, or 500 mg/kg bodyweight) or α-tocopherol (100, 300, or 500 mg/kg bodyweight). We estimated the inhibitory effects on CCl(4)-induced hepatopathy based on hepatic function-associated parameters, oxidative damage-associated parameters and histological changes. The results revealed that the therapeutic effects of radon inhalation were almost equivalent to treatment with ascorbic acid at a dose of 500 mg/kg or α-tocopherol at a dose of 300 mg/kg. The activities of superoxide dismutase, catalase, and glutathione peroxidase in the liver were significantly higher in mice exposed to radon than in mice treated with CCl(4) alone. These findings suggest that radon inhalation has an anti-oxidative effect against CCl(4)-induced hepatopathy similar to the anti-oxidative effects of ascorbic acid or α-tocopherol due to the induction of anti-oxidative functions.

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...

Chemiluminescence behaviour of CdTe-potassium permanganate enhanced by sodium hexametaphosphate and sensitized sensing of L-ascorbic acid.

PubMed

Chen, Hongqi; Ling, Bo; Yuan, Fei; Zhou, Cailing; Chen, Jingguo; Wang, Lun

2012-01-01

A highly sensitive flow-injection chemiluminescence (FIA-CL) method based on the CdTe nanocrystals and potassium permanganate chemiluminescence system was developed for the determination of L-ascorbic acid. It was found that sodium hexametaphosphate (SP), as an enhancer, could increase the chemiluminescence (CL) emission from the redox reaction of CdTe quantum dots with potassium permanganate in near-neutral pH conditions. L-ascorbic acid is suggested as a sensitive enhancer for use in the above energy-transfer excitation process. Under optimal conditions, the calibration graph of emission intensity against logarithmic l-ascorbic acid concentration was linear in the range 1.0 × 10(-9)-5.0 × 10(-6)  mol/L, with a correlation coefficient of 0.9969 and relative standard deviation (RSD) of 2.3% (n = 7) at 5.0 × 10(-7)  mol/L. The method was successfully used to determine L-ascorbic acid in vitamin C tablets. The possible mechanism of the chemiluminescence in the system is also discussed. Copyright © 2012 John Wiley & Sons, Ltd.

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.

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.

[Actual vitamin and main foodstuffs consumption by recovered patients suffered from hemorrhagic fever with renal syndrome].

PubMed

Kasanova, G M; Tutel'ian, A V

2011-01-01

Actual consumption of vitamins A, E, beta-carotene, ascorbic acid, thiamin, pyridoxine and main foodstuffs by recovered patients suffered from hemorrhagic fever with renal syndrome has been given. Frequency analysis of foodstuffs consumption was used to study actual nourishment of recovered patients. Surplus consumption of fat mainly due to the use of saturated fatty acids, deficiency of poly unsaturated fatty acids, surplus sugar consumption and predominance of proteins of animal origin over proteins of vegetable origin in ration has been revealed. Deficiency of water soluble vitamins equals to 41,6-78,7% of all examined patients, deficiency of fat water soluble vitamins is lower (21,4-38,3%).

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.

Vitamin C Status of Submariners

DTIC Science & Technology

1980-06-19

one week of collection using a modification of the 2,4- dinitrophenylhydrazine method of Roe and Kuether (14). Before each sampling period, the...KUETHER. The determination of ascorbic acid in whole blood through the 2,4- dinitrophenylhydrazine derivative of dehydroascorbic acid. J. Biol

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.

Quality index, consumer acceptability, bioactive compounds, and antioxidant activity of fresh-cut "ataulfo" mangoes (mangifera indica L.) as affected by low-temperature storage.

PubMed

Robles-Sánchez, R M; Islas-Osuna, M A; Astiazarán-García, H; Vázquez-Ortiz, F A; Martín-Belloso, O; Gorinstein, S; González-Aguilar, G A

2009-04-01

To measure bioactive compound losses due to minimal processing, mature green fresh-cut mangoes (Mangifera indica L.) cv. "Ataulfo" were subjected to an antioxidant treatment and stored at 5 degrees C during 15 d. Quality index, total phenols, flavonoids, beta-carotene, ascorbic acid, vitamin E, and antioxidant activity were measured during the storage period of fruits. Antioxidant capacity was estimated using ORAC(FL), TEAC, and DPPH assays. The dipping treatments with ascorbic acid (AA) + citric acid (CA) + CaCl2 affected positively quality delaying deterioration of fresh-cut mango as compared with whole fruit. However, dipping treatment affected the consumer preferences of fresh-cut mangoes. The highest vitamin C, beta-carotene, and vitamin E losses were observed after 10 d, being similar in whole and fresh-cut mangoes. The antioxidant activity was not significantly affected by storage time. We conclude that fresh-cut mangoes retained their bioactive compound content during storage and their antioxidant and nutritional properties make them a good source of these compounds.

Vitamin A and C compounds permitted in supplements differ in their abilities to affect cell viability, DNA and the DNA nucleoside deoxyguanosine.

PubMed

Bergström, Therese; Bergman, Jan; Möller, Lennart

2011-11-01

In accordance with the European Parliament and Council's directive, vitamin A and C supplements can include any of four (vitamin A) or five (vitamin C) specified compounds. This study focuses on these compounds and compares their abilities to affect the DNA and viability of cells in culture, but also their potencies to chemically oxidise the DNA nucleoside deoxyguanosine (dG). To study the vitamins' strict chemical oxidation potencies, dG was exposed to vitamin solution and the amount of the oxidation product 8'-hydroxydeoxyguanosine (8-oxodG) formed was estimated using a high-performance liquid chromatography system with electrochemical and ultraviolet detection. The vitamin's ability to cause DNA damage to promyelocytic leukaemia cells (HL-60), as detected by strand breaks, alkaline labile sites and formamido pyrimidine DNA glycosylase (FPG)-sensitive sites was, after vitamin exposure, measured using the comet assay and cytotoxicity was estimated using trypan blue staining. The results highlight that vitamin A and C compounds found in supplements do have different properties, chemically as well as in a cellular system. Among the vitamin C compounds, ascorbic acid, sodium ascorbate and calcium ascorbate stood out causing both oxidation to dG and cytotoxicity to cells. The vitamin A compounds retinol, retinyl acetate and retinal (a breakdown product found in vivo) caused oxidation of dG, while retinal was the only compound causing cytotoxicity, giving rise to an almost complete cell death. β-carotene caused, as the only vitamin compound, a small increase in FPG-sensitive sites. It is concluded that even though the compounds are found under the same name (vitamin A or C), they do have different properties linked to oxidation, cytotoxicity and DNA damage.

RP-HPLC determination of water-soluble vitamins in honey.

PubMed

Ciulu, Marco; Solinas, Silvia; Floris, Ignazio; Panzanelli, Angelo; Pilo, Maria I; Piu, Paola C; Spano, Nadia; Sanna, Gavino

2011-01-15

The assessment and validation of reliable analytical methods for the determination of vitamins in sugar-based matrices (e.g. honey) are still scarcely explored fields of research. This study proposes and fully validates a simple and fast RP-HPLC method for the simultaneous determination of five water-soluble vitamins (vitamin B(2), riboflavin; vitamin B(3), nicotinic acid; vitamin B(5), pantothenic acid; vitamin B(9), folic acid; and vitamin C, ascorbic acid) in honey. The method provides low detection and quantification limits, very good linearity in a large concentration interval, very good precision, and the absence of any bias. It has been successfully applied to 28 honey samples (mainly from Sardinia, Italy) of 12 different botanical origins. While the overall amount of the analytes in the samples is quite low (always below 40 mg kg(-1)), we have observed a marked dependence of some of their concentrations (i.e. vitamin B(3) and vitamin B(5)) and the botanical origin of the honey. This insight might lead to important characterization features for this food item. Copyright © 2010 Elsevier B.V. All rights reserved.

Comparative study on the inhibitory effects of antioxidant vitamins and radon on carbon tetrachloride-induced hepatopathy

PubMed Central

Kataoka, Takahiro; Nishiyama, Yuichi; Yamato, Keiko; Teraoka, Junichi; Morii, Yuji; Sakoda, Akihiro; Ishimori, Yuu; Taguchi, Takehito; Yamaoka, Kiyonori

2012-01-01

We have previously reported that radon inhalation activates anti-oxidative functions and inhibits carbon tetrachloride (CCl4)-induced hepatopathy. It has also been reported that antioxidant vitamins can inhibit CCl4-induced hepatopathy. In the current study, we examined the comparative efficacy of treatment with radon, ascorbic acid and α-tocopherol on CCl4-induced hepatopathy. Mice were subjected to intraperitoneal injection of CCl4 after inhaling approximately 1000 or 2000 Bq/m3 radon for 24 h, or immediately after intraperitoneal injection of ascorbic acid (100, 300, or 500 mg/kg bodyweight) or α-tocopherol (100, 300, or 500 mg/kg bodyweight). We estimated the inhibitory effects on CCl4-induced hepatopathy based on hepatic function-associated parameters, oxidative damage-associated parameters and histological changes. The results revealed that the therapeutic effects of radon inhalation were almost equivalent to treatment with ascorbic acid at a dose of 500 mg/kg or α-tocopherol at a dose of 300 mg/kg. The activities of superoxide dismutase, catalase, and glutathione peroxidase in the liver were significantly higher in mice exposed to radon than in mice treated with CCl4 alone. These findings suggest that radon inhalation has an anti-oxidative effect against CCl4-induced hepatopathy similar to the anti-oxidative effects of ascorbic acid or α-tocopherol due to the induction of anti-oxidative functions. PMID:23111757

Alteration of chemical behavior of L-ascorbic acid in combination with nickel sulfate at different pH solutions in vitro

PubMed Central

Maniyar, Shaheen A; Jargar, Jameel G; Das, Swastika N; Dhundasi, Salim A; Das, Kusal K

2012-01-01

Objective To evaluate the alteration of chemical behavior of L-ascorbic acid (vitamin C) with metal ion (nickel) at different pH solutions in vitro. Methods Spectra of pure aqueous solution of L-ascorbic acid (E mark) compound and NiSO4 (H2O) (sigma USA) were evaluated by UV visible spectrophotometer. Spectral analysis of L-ascorbic acid and nickel at various pH (2.0, 7.0, 7.4 and 8.6) at room temperature of 29 °C was recorded. In this special analysis, combined solution of L-ascorbic acid and nickel sulfate at different pH was also recorded. Results The result revealed that λmax (peak wavelength of spectra) of L-ascorbic acid at pH 2.0 was 289.0 nm whereas at neutral pH 7.0, λmax was 295.4 nm. In alkaline pH 8.6, λmax was 295.4 nm and at pH 7.4 the λmax of L-ascorbic acid remained the same as 295.4 nm. Nickel solution at acidic pH 2.0 was 394.5 nm, whereas at neutral pH 7.0 and pH 7.4 were the same as 394.5 nm. But at alkaline pH 8.6, λmax value of nickel sulfate became 392.0 nm. The combined solution of L-ascorbic acid and nickel sulfate (6 mg/mL each) at pH 2.0 showed 292.5 nm and 392.5 nm, respectively whereas at pH 7.0, L-ascorbic acid showed 296.5 nm and nickel sulfate showed 391.5 nm. At pH 7.4, L-ascorbic acid showed 297.0 nm and nickel sulfate showed 394.0 nm in the combined solution whereas at pH 8.6 (alkaline) L-ascorbic acid and nickel sulfate were showing 297.0 and 393.5 nm, respectively. Conclusions Results clearly indicate an altered chemical behavior of L-ascorbic acid either alone or in combination with nickel sulfate in vitro at different pH. Perhaps oxidation of L-ascorbic acid to L-dehydro ascorbic acid via the free radical (HSc*) generation from the reaction of H2ASc + Ni (II) is the cause of such alteration of λmax value of L-ascorbic acid in the presence of metal nickel. PMID:23569901

"As Simple as Possible, but Not Simpler"--The Case of Dehydroascorbic Acid

ERIC Educational Resources Information Center

Kerber, Robert C.

2008-01-01

Ascorbic acid (vitamin C) is an essential nutrient, whose metabolic roles depend on its function as a reducing agent. Textbooks routinely assign its oxidized form, dehydroascorbic acid, a tricarbonyl structure that is highly improbable in aqueous solution and inconsistent with its colorless appearance. The actual structures of the various forms of…

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.

Drug-nutrient interaction.

PubMed

Matsui, M S; Rozovski, S J

1982-01-01

The effect of certain drugs on nutrient metabolism is discussed. Antituberculotic drugs such as INH and cycloserine interfere with vitamin B6 metabolism and may produce a secondary niacin deficiency. Oral contraceptives interfere with the metabolism of folic acid and ascorbic acid, and in cases of deficient nutrition, they also seem to interfere with riboflavin. Anticonvulsants can act as folate antagonists and precipitate folic acid deficiency. Therefore, in some cases, supplementation with folate has been recommended simultaneously with anticonvulsant therapy. Cholestyramine therapy has been associated with malabsorption of vitamins; several reports suggest that cholestyramine affects absorption of the fat-soluble vitamins K and D and, in addition, may alter water-soluble vitamins, including folic acid. The study of the interaction of drugs and nutrients is an area that deserves a greater attention in the future, especially in groups where nutrient deficiencies may be prevalent.

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.

Selected micronutrient intake and the risk of colorectal cancer.

PubMed Central

Ferraroni, M.; La Vecchia, C.; D'Avanzo, B.; Negri, E.; Franceschi, S.; Decarli, A.

1994-01-01

The relationship between estimated intake of selected micronutrients and the risk of colorectal cancer was analysed using data from a case-control study conducted in northern Italy. The study was based on 828 patients with colon cancer, 498 with rectal cancer and 2,024 controls in hospital for acute, non-neoplastic, non-digestive tract diseases. Relative risks (RRs) of intake quintiles were computed after allowance for age, sex and other major potential confounding factors, including an estimate of total energy intake. No apparent trend in risk across intake quintiles was evident for retinol, vitamin D, methionine and calcium. For beta-carotene, ascorbic acid, vitamin E and folate there was a trend of a protective effect with increasing consumption: the RR for the highest versus the lowest quintile was 0.32 for beta-carotene, 0.40 for ascorbic acid, 0.60 for vitamin E and 0.52 for folate. These inverse associations were similar for colon and rectal cancer, and consistent across strata of sex and age. When simultaneous allowance was made for all these micronutrients, besides other covariates, the only persistent protective effects were for beta-carotene (RR = 0.38 for the highest quintile) and ascorbic acid (RR = 0.52). Whether this reflects a specific, or stronger, effect of these micronutrients, rather than problems of collinearity between micronutrients or other limitations of the data, remains open to discussion. Still, this study suggests that specific micronutrients may exert an independent protective effect against colorectal carcinogenesis. PMID:7981067

Comparative study of the antimutagenic properties of vitamins C and E against mutation induced by norfloxacin

PubMed Central

Alba, Myriam Arriaga; Sánchez, Roberto Rivera; Pérez, Nancy Jannet Ruíz; Navarrete, Jaime Sánchez; Paz, Rocío Flores; Montoya-Estrada, Araceli; Gómez, Juan José Hicks

2008-01-01

Background Norfloxacin like other fluoroquinolones, is known to be mutagenic for Salmonella typhimurium TA102 strain. This mutagenic effect is due to free oxygen radicals (ROS), because it is inhibited by antioxidants such as β-carotene and naturally occurring antioxidants of Roheo discolor and other plants. The aim of this work was to evaluate combination therapy with norfloxacin and vitamins C and E, to reduce the possible genotoxic risk associated with fluoroquinolones. Method The antimutagenicity of α-tocoferol (Vitamin E) and ascorbic acid (Vitamin C) against norfloxacin-induced mutation was evaluated on S. typhimurium TA102, using the aroclor-1254-induced S9 rat liver homogenate. The minimum inhibitory concentration (MIC) a measure of the bactericidal effect of norfloxacin, was obtained in vitro by the plate dilution method. Results Vitamin E (0.5 mg per Petri dish) induced a statistically significant reduction (P < 0.001) in the mutagenicity of norfloxacin, whereas Vitamin C (1 mg per Petri dish) had no such effect. Neither of these vitamins altered the MIC for norfloxacin against 25 uropathogenic strains of Escherichia coli. Conclusion These results suggest that Vitamin E is a potent antimutagen that would be worthwhile being used in conjunction with fluoroquinolone treatment. The minimal antimutagenic effect of Vitamin C observed under these experimental conditions may have been because Vitamin C in the Ames test induces a Fenton reaction, and if divalent cations are present, it can act as a pro-oxidant rather than an antioxidant. Ascorbic acid should be further evaluated in the presence of different divalent cations concentrations. PMID:18267022

Analysis of in vitro release through reconstructed human epidermis and synthetic membranes of multi-vitamins from cosmetic formulations.

PubMed

Gabbanini, Simone; Matera, Riccardo; Beltramini, Claudia; Minghetti, Andrea; Valgimigli, Luca

2010-08-01

A convenient method for in vitro investigation of the release of lipid- and water-soluble vitamins from cosmetic formulations was developed. The permeation of (d)-alpha-tocopherol (vitamin E), retinyl acetate (pro-vitamin A), ascorbic acid (vitamin C) and pyridoxine (vitamin B6) through SkinEthic reconstructed human epidermis (RHE), and synthetic polyethersulfone and polycarbonate membranes was studied in vitro using a Franz-type diffusion apparatus, coupled either to a spectrophotometer for continuous reading (dynamic setting) or to HPLC-DAD analysis of the receptor medium (static setting). O/W and W/O emulsions were compared with simple aqueous solutions for their kinetic of vitamins release, to evaluate the influence of the cosmetic formulation on the bioavailability of active ingredients. Results indicate that synthetic membranes offer a limited barrier to the diffusion of vitamins, but may provide information on the release ability of the formulation. Penetration was more effective when water was the external phase of the formulation, i.e. W/O emulsions were less effective in the release of vitamins than O/W emulsion or aqueous solutions. RHE (17 days old) offered a significantly higher barrier to penetration of vitamins, as expected for native human epidermis. The relative ranking in coefficient of permeability (Ps (cm/h)) was: ascorbic acid>pyridoxine>retinyl acetate>alpha-tocopherol approximately 0, the absolute values depending on the formulation. The method herein described showed to be a practical and convenient tool for the quality-control and efficacy evaluation of cosmetic formulations. Copyright (c) 2010 Elsevier B.V. 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 initiated by the hydrolysis of dehydroascorbate to 2,3-diketo-l-gulonate, which is spontaneously degraded to oxalate, CO(2) and l-erythrulose. This is at variance with bacteria such as Escherichia coli, which have enzymatic degradation pathways for ascorbate and probably also dehydroascorbate.

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.

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.

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.

The effect of vitamin C deficiency and chronic ultraviolet-B exposure on corneal ultrastructure: a preliminary investigation

PubMed Central

Hayes, Sally; Cafaro, Thamara A.; Boguslawska, Patrycja J.; Kamma-Lorger, Christina S.; Boote, Craig; Harris, Jonathan; Young, Robert; Hiller, Jennifer; Terrill, Nicholas; Meek, Keith M.

2011-01-01

Purpose In the visually debilitating condition of climatic droplet keratopathy, corneal transparency is progressively lost. Although the precise cause of the disease and the mechanism by which it progresses are not known, a lifetime exposure to high solar radiation and a vitamin C–deficient diet may be involved in its development. This study examines the effect of dietary ascorbate levels and ultraviolet (UV)-B exposure on corneal stromal structure. Methods Eight guinea pigs were divided into four treatment groups (A, B, C, and D). For 15 weeks, Groups A and C were fed an ascorbate-rich diet (2 mg/100 g bodyweight/day), while Groups B and D received an ascorbate-deficient diet (0.07 mg/100 g bodyweight/day). For the last 12 weeks of the study, Groups C and D also experienced chronic UVB exposure (0.12 J/cm2 for 40 min/day). Following euthanasia, the corneas were enucleated and their stromal ultrastructure examined using X-ray scattering and electron microscopy. Results UVB exposure resulted in an increased corneal thickness (p<0.001), but this was not accompanied by a widespread expansion of the collagen fibrillar array, and in the case of ascorbate-deficient animals, stromal thickening was associated with the compaction of collagen fibrils (p<0.01). Neither UVB exposure nor ascorbic acid deficiency caused any change in the average diameter or D-periodicity of the stromal collagen fibrils. Conclusions UVB-induced changes in the corneal ultrastructure were most pronounced in animals fed an ascorbic acid–deficient diet. This suggests that ascorbic acid may play a vital role in protecting the corneal stroma from the harmful effects of UVB. PMID:22171156

Characterization and quantitation of antioxidant constituents of sweet pepper (Capsicum annuum L.).

PubMed

Marín, Alicia; Ferreres, Federico; Tomás-Barberán, Francisco A; Gil, María I

2004-06-16

Sweet peppers (Capsicum annuum L.) cv. Vergasa have been studied at four maturity stages (immature green, green, immature red, and red). The individual phenolics (hydroxycinnamic acids and flavonoids), vitamin C (ascorbic acid and dehydroascorbic acid), and individual carotenoids were characterized and quantified. Five hydroxycinnamic derivatives and 23 flavonoids were characterized and quantified from the pericarp of sweet pepper by high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Identification was carried out by their UV spectra, chromatographic comparisons with authentic markers, identification of hydrolysis products, and tandem mass spectrometry analysis. Hydroxycinnamic derivatives, O-glycosides of quercetin, luteolin, and chrysoeriol, and a large number of C-glycosyl flavones have been characterized. Some of these compounds were found for the first time in nature. Clear differences in the individual and total phenolic content were detected between the different maturity stages. Immature green pepper had a very high phenolic content while green, immature red, and red ripe peppers showed a 4-5-fold reduction. Ascorbic acid was the main form of vitamin C, and its content increased as the pepper reached maturity. The red ripe stage had a relevant impact on the carotenoids content. Thus, immature green peppers showed the highest content of polyphenols, while red ripe fruits had the highest content of vitamin C and provitamin A.

Study to explore the mechanism to form inclusion complexes of β-cyclodextrin with vitamin molecules

PubMed Central

Saha, Subhadeep; Roy, Aditi; Roy, Kanak; Roy, Mahendra Nath

2016-01-01

Host–guest inclusion complexes of β-cyclodextrin with two vitamins viz., nicotinic acid and ascorbic acid in aqueous medium have been explored by reliable spectroscopic, physicochemical and calorimetric methods as stabilizer, carrier and regulatory releaser of the guest molecules. Job’s plots have been drawn by UV-visible spectroscopy to confirm the 1:1 stoichiometry of the host-guest assembly. Stereo-chemical nature of the inclusion complexes has been explained by 2D NMR spectroscopy. Surface tension and conductivity studies further support the inclusion process. Association constants for the vitamin-β-CD inclusion complexes have been calculated by UV-visible spectroscopy using both Benesi–Hildebrand method and non-linear programme, while the thermodynamic parameters have been estimated with the help of van’t Hoff equation. Isothermal titration calorimetric studies have been performed to determine the stoichiometry, association constant and thermodynamic parameters with high accuracy. The outcomes reveal that there is a drop in ΔSo, which is overcome by higher negative value of ΔHo, making the overall inclusion process thermodynamically favorable. The association constant is found to be higher for ascorbic acid than that for nicotinic acid, which has been explained on the basis of their molecular structures. PMID:27762346

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

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.

AM fungi and PGP pseudomonads increase flowering, fruit production, and vitamin content in strawberry grown at low nitrogen and phosphorus levels.

PubMed

Bona, Elisa; Lingua, Guido; Manassero, Paola; Cantamessa, Simone; Marsano, Francesco; Todeschini, Valeria; Copetta, Andrea; D'Agostino, Giovanni; Massa, Nadia; Avidano, Lorena; Gamalero, Elisa; Berta, Graziella

2015-04-01

There is increasing interest in the quality of crops because of the implications concerning health, economic revenue, and food quality. Here we tested if inoculation with a mixture of arbuscular mycorrhizal fungi (AMF) and/or two strains of plant growth-promoting bacteria (PGPB), in conditions of reduced chemical inputs, affects the quality and yield of strawberry fruits. Fruit quality was measured by concentrations of soluble sugars, various organic acids, and two vitamins (ascorbic and folic acid). Co-inoculation with the AMF and each of the two PGPB resulted in increased flower and fruit production, larger fruit size, and higher concentrations of sugars and ascorbic and folic acid in comparison with fruits of uninoculated plants. These results provide further evidence that rhizospheric microorganisms affect fruit crop quality and show that they do so even under conditions of reduced chemical fertilization and can thus be exploited for sustainable agriculture.

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.

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.

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.

Nitrate, ascorbic acid, mineral and antioxidant activities of Cosmos caudatus in response to organic and mineral-based fertilizer rates.

PubMed

Hassan, Siti Aishah; Mijin, Salumiah; Yusoff, Umi Kalsom; Ding, Phebe; Wahab, Puteri Edaroyati Megat

2012-06-28

The source and quantity of nutrients available to plants can affect the quality of leafy herbs. A study was conducted to compare quality of Cosmos caudatus in response to rates of organic and mineral-based fertilizers. Organic based fertilizer GOBI (8% N:8% P₂O₅:8% K₂O) and inorganic fertilizer (15% N, 15% P₂O₅, 15% K₂O) were evaluated based on N element rates at 0, 30, 60, 90, 120 kg h⁻¹. Application of organic based fertilizer reduced nitrate, improved vitamin C, antioxidant activity as well as nitrogen and calcium nutrients content. Antioxidant activity and chlorophyll content were significantly higher with increased fertilizer application. Fertilization appeared to enhance vitamin C content, however for the maximum ascorbic acid content, regardless of fertilizer sources, plants did not require high amounts of fertilizer.

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.

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.

Water-soluble vitamins.

PubMed

Konings, Erik J M

2006-01-01

Simultaneous Determination of Vitamins.--Klejdus et al. described a simultaneous determination of 10 water- and 10 fat-soluble vitamins in pharmaceutical preparations by liquid chromatography-diode-array detection (LC-DAD). A combined isocratic and linear gradient allowed separation of vitamins in 3 distinct groups: polar, low-polar, and nonpolar. The method was applied to pharmaceutical preparations, fortified powdered drinks, and food samples, for which results were in good agreement with values claimed. Heudi et al. described a separation of 9 water-soluble vitamins by LC-UV. The method was applied for the quantification of vitamins in polyvitaminated premixes used for the fortification of infant nutrition products. The repeatability of the method was evaluated at different concentration levels and coefficients of variation were <6.5%. The concentrations of vitamins found in premixes with the method were comparable to the values declared. A disadvantage of the methods mentioned above is that sample composition has to be known in advance. According to European legislation, for example, foods might be fortified with riboflavin phosphate or thiamin phosphate, vitamers which are not included in the simultaneous separations described. Vitamin B2.--Viñas et al. elaborated an LC analysis of riboflavin vitamers in foods. Vitamin B2 can be found in nature as the free riboflavin, but in most biological materials it occurs predominantly in the form of 2 coenzymes, flavin mononucleotide (FMN) and flavin-adenine dinucleotide (FAD). Several methods usually involve the conversion of these coenzymes into free riboflavin before quantification of total riboflavin. According to the authors, there is growing interest to know flavin composition of foods. The described method separates the individual vitamers isocratically. Accuracy of the method is tested with 2 certified reference materials (CRMs). Vitamin B5.-Methods for the determination of vitamin B5 in foods are limited 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 foods using L-methionine for the pre-analysis sample stabilization. Electrochemical detection was used for the quantification. Traditionally, metaphosphoric acid was proven to be a useful dissolving agent for the determination of ascorbic acid. However, it dissolves in water very slowly, it is hygroscopic, and accurate weighing is not easy. Adjustment at pH 2-3 takes a long time. It appeared to be possible to replace metaphosphoric acid by 0.2% phosphoric acid. Methionine played an important role on the stability of ascorbic acid. The method seemed to be applicable to the routine analysis of ascorbic acid in foods. Folic Acid.-Microbiological analysis of total folate in foods is often considered as the golden standard compared to other methods based on, for example, LC. Koontz et al. showed results of total folate concentrations measured by microbiological assay in a variety of foods. Samples were submitted in a routine manner to experienced laboratories that regularly perform folate analysis fee-for-service basis in the United States. Each laboratory reported the use of a microbiological method similar to the AOAC Official Method for the determination of folic acid. Striking was, the use of 3 different pH extraction conditions by 4 laboratories. Only one laboratory reported using a tri-enzyme extraction. Results were evaluated. Results for folic acid fortified foods had considerably lower between-laboratory variation, 9-11%, versus >45% for other foods. Mean total folate ranged from 14 to 279 microg/100 g for a mixed vegetable reference material, from 5 to 70 microg/100 g for strawberries, and from 28 to 81 microg/100 g for wholemeal flour. One should realize a large variation in results, which might be caused by slight modifications in the microbiological analysis of total folate in foods or the analysis in various (unfortified) food matrixes. Furthermore, optimal combination of enzymes and reaction conditions may vary depending on the composition of the food. Padrangi and Laborde showed recently that treatment with alpha-amylase had no significant effect on measured folate in spinach, although addition of protease significantly increased the release of folate. LC/MS applications gain increasing attention because of their specificity. Rychlik used stable isotope dilution assays for the determination of the folate content of broccoli and bread. Compared to data in the literature and food data bases, amounts were significantly lower. Pawlosky et al., however, found comparable values for 5-methyltetrahydrofolic acid and folic acid by HPLC analysis with fluorescent detection and HPLC/MS. Among samples analyzed were CRMs and broccoli. Besides folic acid, other water-soluble vitamins were also determined by LC/MS/MS by Leporati et al. The method was applied to the quantitative analysis of the natural content of vitamins in typical Italian pasta samples, as well as in fortified pasta samples produced for the U.S. market. Biotin.-A paper from Staggs et al. included the assertion that existing biotin data in food composition tables are inaccurate because the majority are based on bioassays with all relevant disadvantages. Data in most cases are overestimated with consequences for recommendations for dietary biotin intake. An HPLC/avidin-binding assay was used to analyze 87 foods to support the hypothesis mentioned.

[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.

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

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.

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.

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 increase the vitamin C levels in pepper fruits. Copyright © 2017. Published by Elsevier B.V.

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 statistical application, but despite this, when all cardiometabolic traits were assessed, there was no evidence of any trend supporting a protective role of L-ascorbic acid. In the context of existing work, these results add to the suggestion that observational relations between L-ascorbic acid and cardiometabolic health may be attributable to confounding and reverse causation.

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 association exploited in this study led to limited statistical application, but despite this, when all cardiometabolic traits were assessed, there was no evidence of any trend supporting a protective role of l-ascorbic acid. In the context of existing work, these results add to the suggestion that observational relations between l-ascorbic acid and cardiometabolic health may be attributable to confounding and reverse causation. PMID:25527764

Modificatory effect of vitamin C and vitamin B-complex on meiotic inhibition induced by organophosphorus pesticide in mice Mus musculus.

PubMed

Hoda, Q; Azfer, M A; Sinha, S P

1993-01-01

Administration of organophosphorous pesticide Malathion and Rogor (both @ 0.2 micrograms/kg body wt/day) upto ten days was found to decrease the division rate in the primary spermatocytes of mice. The concurrent administration of vitamin B-complex (0.3 ml of 1% polybion) or ascorbic acid (0.25 ml of 1% Redoxon) with the pesticide could nullify the meiotic inhibition caused by the pesticides. The vitamins were not found to produce any significant effect on the division rate. Possible mechanism(s) behind this vitamin mediated nullification of meiotic inhibition are discussed.

A Study of Intravenous Administration of Vitamin C in the Treatment of Acute Herpetic Pain and Postherpetic Neuralgia

PubMed Central

Kim, Min Sung; Kim, Dong Jin; Na, Chan Ho

2016-01-01

Background Although there are several available management strategies for treatment of both acute pain of herpes zoster (HZ) and postherpetic neuralgia (PHN), it is difficult to treat them adequately. Objective The aim of this study was to evaluate the efficacy of intravenously administrated vitamin C on acute pain and its preventive effects on PHN in patients with HZ. Methods Between September 2011 and May 2013 eighty-seven patients who were admitted for HZ were assessed according to age, sex, underlying diseases, duration of pain and skin lesion, dermatomal distribution, and PHN. It was a randomized controlled study, in which 87 patients were randomly allocated into the ascorbic acid group and control group. Each patient received normal saline infusion with or without 5 g of ascorbic acid on days 1, 3, and 5 then answered questionnaires that included side effects and pain severity using visual analogue scale on days 1, 2, 3, 4, and 5. After discharge, the severity of pain was obtained at out-patient clinic or by telephone on weeks 2, 4, 8, and 16. Results There was no differences in severity of pain on patients' age, sex, underlying diseases, duration of pain and skin lesion and dermatomal distribution between two groups (p>0.05). Since 8th week, pain score in ascorbic acid treatment group was significantly lower than control group (p <0.05). The incidence of PHN was significantly lower in the treatment group compared to control group (p=0.014). The changes of overall pain score was significantly different between the two groups (p<0.05). Conclusion Intravenously administered ascorbic acid did not relieve acute HZ pain; but is effective for reducing the incidence of PHN. PMID:27904265

Combined effects of retinol, ascorbic acid and α-tocopherol on diurnal variations in rectal temperature of Black Harco pullets subjected to heat stress

NASA Astrophysics Data System (ADS)

Sinkalu, Victor Olusegun; Ayo, Joseph Olusegun

2018-01-01

The experiment was performed with the aim of determining the effect of co-administration of antioxidant vitamins, retinol, ascorbic acid and α-tocopherol on rectal temperature (RT) fluctuations in pullets during the hot-dry season in Nigeria. Forty-eight Black Harco pullets, aged 16 weeks and weighing 1.5 ± 0.03 kg were divided by simple random sampling into two groups, consisting of 28 treated and 20 control Black Harco pullets. The RTs of 28 treated and 20 control Black Harco pullets were measured hourly for 3 days, 3 days apart, from 06:00 to 19:00 h (GMT + 1) with a standard clinical thermometer. The treated pullets were administered individually with the vitamins orally in water, while the control pullets were given only water. The lowest hourly RT of 40.9 ± 0.04 °C was obtained in treated pullets at 06:00 h, while the highest value of 41.1 ± 0.01 °C was recorded from 17:00 to 19:00 h ( P < 0.001). In control pullets, the RT rose significantly from 41.0 ± 0.03 °C at 06:00 h to the maximum value of 41.6 ± 0.04 °C at 15:00 h ( P < 0.001). The pullets co-administered with retinol, ascorbic acid and α-tocopherol had consistently lower RT values than those of control pullets, especially during the hot hours of the day, from 13:00 to 17:00 h. It is concluded that co-administration of retinol, ascorbic acid and α-tocopherol, by preventing a rise in body temperature, ameliorated heat stress, and may enhance productivity of pullets reared under unfavourable, thermal environment conditions.

Vitamin C with metabolites: additional analysis suggests favorable changes in oxalate.

PubMed

Moyad, Mark A; Combs, Maile A; Baisley, Joshua E; Evans, Malkanthi

2009-01-01

A previously published randomized trial found a significant difference in the proportion of individuals experiencing oxalate reduction with a vitamin C with metabolites product compared with ascorbic acid (vitamin C). This represented a notable finding, which argued against the possibility of a chance finding due to the design and consistency of results. However, these researchers believed it was necessary to further analyze this study to continue to garner more insight on the strength or weakness of original findings. All favorable, neutral, and non-favorable changes of 24-hour oxalate from the previous clinical trial were grouped. Oxalate was considered to "decrease" or "increase" with each intervention only if a 10% or larger change occurred in the 24-hour oxalate baseline value when taking one product compared to another. A greater proportion of subjects taking both products at different time periods experienced favorable oxalate changes with vitamin C with metabolites product compared to ascorbic acid. If this reflects the true clinical scenario, this would represent an important clinical finding on a population level because at least 20% more individuals would experience a more favorable change. Regardless, this further analysis continues to suggest that the original observations were valid and could have positive clinical implications for some patients.

[Estimation of vitamin status of moscow student according to data on vitamins intake and their levels in blood].

PubMed

Beketova, N A; Kodentsova, V M; Vrzhesinskaya, O A; Kosheleva, O V; Pereverzeva, O G; Solntseva, T N; Pogozheva, A V; Khanferyan, R A; Berketova, L V; Lipatova, L P

Supply with vitamins C, A, E and B2 of 61 high school students (38 girls and 23 boys, aged 18–22 years, body mass index – 23.0±0.6 kg/m2) by means of determination of blood plasma concentration of ascorbic acid, retinol and carotenoids, tocopherols and riboflavin has been investigated in the period from May to September. All students were well supplied with vitamin C (only 2 boys had a reduced level of ascorbic acid) and vitamin A. Decreased level of carotenoids was more common in boys (48 versus 24% in girls). 20% of the students were insufficiently supplied with vitamin E, 38% – with vitamin B2. 39% of students (50% girls and 22% boys) were adequately provided with all studied vitamins. 5% of the students had a combined deficiency of 3 vitamins, 20% – 2 vitamins. Student’s sufficiency with vitamins B2, C, A, E, carotenoids did not depend on the season. Diet intake of vitamins C, A, carotenoids and vitamin B2 has been calculated basing on the data on the frequency of food consumption during the previous month. Reduced consumption relatively to the Russia RDA of vitamins В2, C and А took place in 63, 54 and 46% of the students respectively. The lack of vitamin B2 in the diet was most pronounced, the value of probabilistic risk corresponded to the average level in 34% of students. Average probabilistic risk of inadequate intake of vitamin A was present in 17% of students, vitamin C – 6%. Coincidence of the results of vitamin C and A status assessment obtained by calculation of vitamin diet intake and by biochemical methods (concentration of vitamins in the blood plasma) was 94 and 83%. These methods are interchangeable if you select the value of the average probability of risk failure intake of these vitamins as a criterion. Proportion of coinciding results of the estimation of vitamin B2 status was 56%. Special well-designed studies on larger sample surveyed are needed for the final output of the interchangeability of methods to assess riboflavin status.

Biochemical profile of African American women during three trimesters of pregnancy and at delivery.

PubMed

Knight, E M; Spurlock, B G; Edwards, C H; Johnson, A A; Oyemade, U J; Cole, O J; West, W L; Manning, M; James, H; Laryea, H

1994-06-01

The data presented are the results from a prospective observational study which was conducted to investigate the effects of nutrition and other related factors on the outcome of pregnancy in nulliparous African American women 16-35 years old. Fasting blood samples were collected from the women during the first, second and third trimesters of pregnancy. At delivery, both maternal and cord samples were collected. Biochemical variables such as, serum folate, vitamin B12, ascorbic acid, vitamin E, ferritin, selected minerals as well as complete blood count (CBC) and red cell folate were analyzed in the blood samples. The concentrations of hematocrit, hemoglobin, white blood cells, red blood cells and vitamin B12 were below the reference non-pregnant ranges throughout gestation. Maternal concentrations of folate and vitamin E increased sequentially with increased gestational age. Serum ferritin, during the third trimester, declined to 58% of the first trimester concentration. Maternal levels of ferritin at delivery were one third of the values found in the infant (cord) sample. Cord levels of folate, ascorbic acid and vitamin B12 were higher than the concentrations in the maternal delivery samples. The data suggest that among this group of pregnant women, major physiological changes, such as plasma volume expansion which alters blood chemistry and maternal to fetal transfer of nutrients, were similar to the findings of other investigators. In this population however, the findings for serum and whole blood folate are contrary to those reported by other researchers, and the sequential increase in the maternal concentration of the vitamin during pregnancy could be attributed to the use of vitamin supplements.

Ordered mesoporous ternary mixed oxide materials as potential adsorbent of biomolecules

NASA Astrophysics Data System (ADS)

Pal, Nabanita; Bhaumik, Asim

2012-05-01

Designing a suitable mesoporous framework material for the selective adsorption or immobilization of biomolecules is a very challenging area of research. Mesoporous ternary Co-Si-Al oxide materials with large mesopore and their nanoscale ordering have been reported. The synthesis of these ternary oxides are accomplished through evaporation induced self-assembly (EISA) method using Pluronic non-ionic surfactant F127 under non-aqueous sol-gel route. N2 sorption study revealed high BET surface areas for these materials. These materials exhibited very efficient and selective adsorption for the essential biomolecules like vitamin C (ascorbic acid), vitamin B6 (pyridoxine) and vitamin B3 (nicotinic acid) from their respective aqueous solutions.

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.

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

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.

Winter illness and vitamin C: the effect of relatively low doses.

PubMed

Anderson, T W; Beaton, G H; Corey, P; Spero, L

1975-04-05

After their random -llocation to one of three treatment aroups, 622 volunteers received either vitamin C or placebo in a maintenance dose of 500 mg once weekly and a therapeutic dose of 1500 mg daily on the 1st day and 1000 mg on the next 4 days of any illness. Two forms of vitamin C were employed: a sustained-release capsule containing ascorbic acid and a regular tabet containing a mixture of sodium and calcium ascorbate. In the 448 subjects who completed an average of 15 weeks in the study of total of 635 episodes of illness were recroded. Respiratory symptoms were recorded on at least 1 day in 92 per cent of these episodes. There were no consistent or significant differences in the sickness experience of the subjects receiving the sustained-release vitamin capsules compared to those receiving the vitamin tablets, but subjects in both vitamin groups experienced less severe illness than subjects in the placebo group, with approximately 25 per cent fewer days spent indoors because of the illness (P smaller than 0.05). These results are compatible with the belief that supplementary vitamin C can reduce the burden of winter illness, but the intake need not be as high as has sometimes been claimed.

Winter illness and vitamin C: the effect of relatively low doses.

PubMed Central

Anderson, T. W.; Beaton, G. H.; Corey, P.; Spero, L.

1975-01-01

After their random -llocation to one of three treatment aroups, 622 volunteers received either vitamin C or placebo in a maintenance dose of 500 mg once weekly and a therapeutic dose of 1500 mg daily on the 1st day and 1000 mg on the next 4 days of any illness. Two forms of vitamin C were employed: a sustained-release capsule containing ascorbic acid and a regular tabet containing a mixture of sodium and calcium ascorbate. In the 448 subjects who completed an average of 15 weeks in the study of total of 635 episodes of illness were recroded. Respiratory symptoms were recorded on at least 1 day in 92 per cent of these episodes. There were no consistent or significant differences in the sickness experience of the subjects receiving the sustained-release vitamin capsules compared to those receiving the vitamin tablets, but subjects in both vitamin groups experienced less severe illness than subjects in the placebo group, with approximately 25 per cent fewer days spent indoors because of the illness (P smaller than 0.05). These results are compatible with the belief that supplementary vitamin C can reduce the burden of winter illness, but the intake need not be as high as has sometimes been claimed. PMID:1091343

Simultaneous determination of eight water-soluble vitamins in supplemented foods by liquid chromatography.

PubMed

Zafra-Gómez, Alberto; Garballo, Antonio; Morales, Juan C; García-Ayuso, Luis E

2006-06-28

A fast, simple, and reliable method for the isolation and determination of the vitamins thiamin, riboflavin, niacin, pantothenic acid, pyridoxine, folic acid, cyanocobalamin, and ascorbic acid in food samples is proposed. The most relevant advantages of the proposed method are the simultaneous determination of the eight more common vitamins in enriched food products and a reduction of the time required for quantitative extraction, because the method consists merely of the addition of a precipitation solution and centrifugation of the sample. Furthermore, this method saves a substantial amount of reagents as compared with official methods, and minimal sample manipulation is achieved due to the few steps required. The chromatographic separation is carried out on a reverse phase C18 column, and the vitamins are detected at different wavelengths by either fluorescence or UV-visible detection. The proposed method was applied to the determination of water-soluble vitamins in supplemented milk, infant nutrition products, and milk powder certified reference material (CRM 421, BCR) with recoveries ranging from 90 to 100%.

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.

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.

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

Vitamin C Transporters in Cancer: Current Understanding and Gaps in Knowledge

PubMed Central

Wohlrab, Christina; Phillips, Elisabeth; Dachs, Gabi U.

2017-01-01

Sufficient uptake and whole body distribution of vitamin C (ascorbate) is essential for many biochemical processes, including some that are vital for tumor growth and spread. Uptake of ascorbate into cancer cells is modulated by availability, tumor blood flow, tissue diffusion parameters, and ascorbate transport proteins. Uptake into cells is mediated by two families of transport proteins, namely, the solute carrier gene family 23, consisting of sodium-dependent vitamin C transporters (SVCTs) 1 and 2, and the SLC2 family of glucose transporters (GLUTs). GLUTs transport the oxidized form of the vitamin, dehydroascorbate (DHA), which is present at negligible to low physiological levels. SVCT1 and 2 are capable of accumulating ascorbate against a concentration gradient from micromolar concentrations outside to millimolar levels inside of cells. Investigating the expression and regulation of SVCTs in cancer has only recently started to be included in studies focused on the role of ascorbate in tumor formation, progression, and response to therapy. This review gives an overview of the current, limited knowledge of ascorbate transport across membranes, as well as tissue distribution, gene expression, and the relevance of SVCTs in cancer. As tumor ascorbate accumulation may play a role in the anticancer activity of high dose ascorbate treatment, further research into ascorbate transport in cancer tissue is vital. PMID:28484682

Assessing manganese nanostructures based carbon nanotubes composite for the highly sensitive determination of vitamin C in pharmaceutical formulation.

PubMed

Hameed, Sadaf; Munawar, Anam; Khan, Waheed S; Mujahid, Adnan; Ihsan, Ayesha; Rehman, Asma; Ahmed, Ishaq; Bajwa, Sadia Z

2017-03-15

This work is the first report describing the development of a novel three dimensional manganese nanostructures based carbon nanotubes (CNTs-Mn NPs) composite, for the determination of ascorbic acid (vitamin C) in pharmaceutical formulation. Carbon nanotubes (CNTs) were used as a conductive skeleton to anchor highly electrolytic manganese nanoparticles (Mn NPs), which were prepared by a hydrothermal method. Scanning electron microscopy and atomic force microscopy revealed the presence of Mn Nps of 20-25nm, anchored along the whole length of CNTs, in the form of patches having a diameter of 50-500nm. Fourier transform infrared spectroscopy confirmed the surface modification of CNTs by amine groups, whereas dynamic light scattering established the presence of positive charge on the prepared nanocomposite. The binding events were studied by monitoring cyclic voltammetry signals and the developed nanosensor exhibited highly sensitive response, demonstrating improved electrochemical activity towards ascorbic acid. Linear dependence of the peak current on the square root of scan rates (R 2 =0.9785), demonstrated that the oxidation of ascorbic acid by the designed nanostructures is a diffusion control mechanism. Furthermore, linear range was found to be 0.06-4.0×10 -3 M, and nanosensor displayed an excellent detection limit of 0.1µM (S/N=3). This developed nanosensor was successfully applied for the determination of vitamin C in pharmaceutical formulation. Besides, the results of the present study indicate that such a sensing platform may offer a different pathway to utilize manganese nanoparticles based CNTs composite for the determination of other bio-molecules as well. Copyright © 2016 Elsevier B.V. All rights reserved.

The relationship between acute changes in the systemic inflammatory response and plasma ascorbic acid, alpha-tocopherol and lipid peroxidation after elective hip arthroplasty.

PubMed

Conway, F J S; Talwar, D; McMillan, D C

2015-08-01

Vitamin C (ascorbic acid, AA) is a water soluble vitamin with many functions including antioxidative properties, haemostasis, hormone synthesis, collagen synthesis, carnitine synthesis, bile salt production and enhancing iron absorption. There is some evidence that there is a negative inverse relationship between plasma vitamin C concentration and the systemic inflammatory response as measured by C-reactive protein (CRP). The aim of the present study was to examine, in the context of a longitudinal study, the change in plasma concentrations of ascorbic acid (AA) and Vitamin E (α-tocopherol, AT) and their relationship to free radical damage during the evolution of the systemic inflammatory response. Venous blood samples were obtained pre-operatively and at 1, 2, 3 and 90 days post-operatively from 11 patients undergoing elective hip arthroplasty at Glasgow Royal Infirmary. AA, AT, cholesterol, MDA (marker of free radical damage), CRP and albumin were measured in plasma. Plasma AA fell significantly by 74% (P < 0.01), AT fell by 36% (P < 0.01), cholesterol by 40% (P < 0.01), MDA by 38% (P < 0.01), albumin by 29% (P < 0.01) and CRP increased significantly by 160 fold (P < 0.01) during the systemic inflammatory response. The fall in plasma AA remained significant when adjusted for albumin (P < 0.01). Plasma AT adjusted for cholesterol did not change significantly during the study period. The fall in plasma MDA remained significant when adjusted for albumin (P 0.01). At 3 months post-operatively, all measurements (including AA) except albumin had returned to baseline values. Plasma AA levels are unlikely to be a reliable measurement of Vitamin C where there is evidence of a systemic inflammatory response. The decrease in plasma AA concentration is likely to be secondary to increased consumption, increased usage neutralising free radicals, increased utilisation in supporting AT regeneration and increased urinary excretion. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

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

A randomised cross-over pharmacokinetic bioavailability study of synthetic versus kiwifruit-derived vitamin C.

PubMed

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

2013-11-11

Kiwifruit are a rich source of vitamin C and also contain numerous phytochemicals, such as flavonoids, which may influence the bioavailability of kiwifruit-derived vitamin C. The aim of this study was to compare the relative bioavailability of synthetic versus kiwifruit-derived vitamin C using a randomised cross-over pharmacokinetic study design. Nine non-smoking males (aged 18-35 years) received either a chewable tablet (200 mg vitamin C) or the equivalent dose from gold kiwifruit (Actinidia chinensis var. Sungold). Fasting blood and urine were collected half hourly to hourly over the eight hours following intervention. The ascorbate content of the plasma and urine was determined using HPLC with electrochemical detection. Plasma ascorbate levels increased from 0.5 h after the intervention (P = 0.008). No significant differences in the plasma time-concentration curves were observed between the two interventions (P = 0.645). An estimate of the total increase in plasma ascorbate indicated complete uptake of the ingested vitamin C tablet and kiwifruit-derived vitamin C. There was an increase in urinary ascorbate excretion, relative to urinary creatinine, from two hours post intervention (P < 0.001). There was also a significant difference between the two interventions, with enhanced ascorbate excretion observed in the kiwifruit group (P = 0.016). Urinary excretion was calculated as ~40% and ~50% of the ingested dose from the vitamin C tablet and kiwifruit arms, respectively. Overall, our pharmacokinetic study has shown comparable relative bioavailability of kiwifruit-derived vitamin C and synthetic vitamin C.

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.

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.

Changes in postharvest quality of Swiss chard grown using 3 organic preharvest treatments.

PubMed

Daiss, N; Lobo, M G; Gonzalez, M

2008-08-01

Using storage conditions recommended for conventional chard (4 degrees C, 90% RH and 7 d), the chard treated with some organic preharvest treatments [effective microorganisms, a fermented mixture of effective microorganisms with organic matter (EM-Bokashi + EM), and an auxiliary soil product] lost considerable water (> 2%) and weight (> 25%). These results indicate that organic methods tested produce a vegetable that can not sustain its quality when commercialized through the conventional supply chain. Nevertheless, respiration, color, pH, and titratable acidity practically remained constant during conservation. Ascorbic acid content was constant in chard treated with the different preharvest treatments and collected at 8 wk after sowing (normal harvest). However, the ascorbic acid content of the control chard decreased 60% after 7 d of storage. This vitamin diminished (35%) in chard collected after 19 wk after sowing (late harvest) during the postharvest conservation. The greatest difference in chard quality was registered between sampling dates since chard collected during the late harvest had higher levels of dry matter, sugars, acids, proteins, and ascorbic acid than chard collected during the normal harvest.

Appropriate Handling, Processing and Analysis of Blood Samples Is Essential to Avoid Oxidation of Vitamin C to Dehydroascorbic Acid

PubMed Central

Pullar, Juliet M.; Carr, Anitra C.

2018-01-01

Vitamin C (ascorbate) is the major water-soluble antioxidant in plasma and its oxidation to dehydroascorbic acid (DHA) has been proposed as a marker of oxidative stress in vivo. However, controversy exists in the literature around the amount of DHA detected in blood samples collected from various patient cohorts. In this study, we report on DHA concentrations in a selection of different clinical cohorts (diabetes, pneumonia, cancer, and critically ill). All clinical samples were collected into EDTA anticoagulant tubes and processed at 4 °C prior to storage at −80 °C for subsequent analysis by HPLC with electrochemical detection. We also investigated the effects of different handling and processing conditions on short-term and long-term ascorbate and DHA stability in vitro and in whole blood and plasma samples. These conditions included metal chelation, anticoagulants (EDTA and heparin), and processing temperatures (ice, 4 °C and room temperature). Analysis of our clinical cohorts indicated very low to negligible DHA concentrations. Samples exhibiting haemolysis contained significantly higher concentrations of DHA. Metal chelation inhibited oxidation of vitamin C in vitro, confirming the involvement of contaminating metal ions. Although EDTA is an effective metal chelator, complexes with transition metal ions are still redox active, thus its use as an anticoagulant can facilitate metal ion-dependent oxidation of vitamin C in whole blood and plasma. Handling and processing blood samples on ice (or at 4 °C) delayed oxidation of vitamin C by a number of hours. A review of the literature regarding DHA concentrations in clinical cohorts highlighted the fact that studies using colourimetric or fluorometric assays reported significantly higher concentrations of DHA compared to those using HPLC with electrochemical detection. In conclusion, careful handling and processing of samples, combined with appropriate analysis, is crucial for accurate determination of ascorbate and DHA in clinical samples. PMID:29439480

Free Radical Reactions in Food.

ERIC Educational Resources Information Center

Taub, Irwin A.

1984-01-01

Discusses reactions of free radicals that determine the chemistry of many fresh, processed, and stored foods. Focuses on reactions involving ascorbic acid, myoglobin, and palmitate radicals as representative radicals derived from a vitamin, metallo-protein, and saturated lipid. Basic concepts related to free radical structure, formation, and…

Kinetic modelling of ascorbic and dehydroascorbic acids concentrations in a model solution at different temperatures and oxygen contents.

PubMed

Gómez Ruiz, Braulio; Roux, Stéphanie; Courtois, Francis; Bonazzi, Catherine

2018-04-01

The degradation kinetics of vitamin C (ascorbic and dehydroascorbic acids, AA and DHA) were determined under controlled conditions of temperature (50-90 °C) and oxygen concentrations in the gas phase (10-30% mol/mol) using a specific reactor. The degradation of vitamin C in malate buffer (20 mM, pH 3.8), mimetic of an apple puree, was assessed by sampling at regular intervals and spectrophotometric quantification of AA and DHA levels at 243 nm. The results showed that AA degradation increased with temperature and oxygen concentration, while DHA exhibited the behaviour of an intermediate species, appearing then disappearing. A kinetic model was successfully developed to simulate the experimental data by two first order consecutive reactions. The first one represented AA degradation as a function of temperature and concentration in dissolved oxygen, and the second reflected DHA degradation as a function of temperature only, both adequately following Arrhenius' law. Copyright © 2018 Elsevier Ltd. All rights reserved.

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 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.

Caveolin-1-mediated internalization of the vitamin C transporter SVCT2 in microglia triggers an inflammatory phenotype.

PubMed

Portugal, Camila C; Socodato, Renato; Canedo, Teresa; Silva, Cátia M; Martins, Tânia; Coreixas, Vivian S M; Loiola, Erick C; Gess, Burkhard; Röhr, Dominik; Santiago, Ana R; Young, Peter; Minshall, Richard D; Paes-de-Carvalho, Roberto; Ambrósio, António F; Relvas, João B

2017-03-28

Vitamin C is essential for the development and function of the central nervous system (CNS). The plasma membrane sodium-vitamin C cotransporter 2 (SVCT2) is the primary mediator of vitamin C uptake in neurons. SVCT2 specifically transports ascorbate, the reduced form of vitamin C, which acts as a reducing agent. We demonstrated that ascorbate uptake through SVCT2 was critical for the homeostasis of microglia, the resident myeloid cells of the CNS that are essential for proper functioning of the nervous tissue. We found that depletion of SVCT2 from the plasma membrane triggered a proinflammatory phenotype in microglia and resulted in microglia activation. Src-mediated phosphorylation of caveolin-1 on Tyr 14 in microglia induced the internalization of SVCT2. Ascorbate treatment, SVCT2 overexpression, or blocking SVCT2 internalization prevented the activation of microglia. Overall, our work demonstrates the importance of the ascorbate transport system for microglial homeostasis and hints that dysregulation of ascorbate transport might play a role in neurological disorders. Copyright © 2017, American Association for the Advancement of Science.

A Randomised Cross-Over Pharmacokinetic Bioavailability Study of Synthetic versus Kiwifruit-Derived Vitamin C

PubMed Central

Carr, Anitra C.; Bozonet, Stephanie M.; Vissers, Margreet C. M.

2013-01-01

Kiwifruit are a rich source of vitamin C and also contain numerous phytochemicals, such as flavonoids, which may influence the bioavailability of kiwifruit-derived vitamin C. The aim of this study was to compare the relative bioavailability of synthetic versus kiwifruit-derived vitamin C using a randomised cross-over pharmacokinetic study design. Nine non-smoking males (aged 18–35 years) received either a chewable tablet (200 mg vitamin C) or the equivalent dose from gold kiwifruit (Actinidia chinensis var. Sungold). Fasting blood and urine were collected half hourly to hourly over the eight hours following intervention. The ascorbate content of the plasma and urine was determined using HPLC with electrochemical detection. Plasma ascorbate levels increased from 0.5 h after the intervention (P = 0.008). No significant differences in the plasma time-concentration curves were observed between the two interventions (P = 0.645). An estimate of the total increase in plasma ascorbate indicated complete uptake of the ingested vitamin C tablet and kiwifruit-derived vitamin C. There was an increase in urinary ascorbate excretion, relative to urinary creatinine, from two hours post intervention (P < 0.001). There was also a significant difference between the two interventions, with enhanced ascorbate excretion observed in the kiwifruit group (P = 0.016). Urinary excretion was calculated as ~40% and ~50% of the ingested dose from the vitamin C tablet and kiwifruit arms, respectively. Overall, our pharmacokinetic study has shown comparable relative bioavailability of kiwifruit-derived vitamin C and synthetic vitamin C. PMID:24284610

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)

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.

Role of Vitamin C in the Function of the Vascular Endothelium

PubMed Central

Harrison, Fiona E.

2013-01-01

Abstract Significance: Vitamin C, or ascorbic acid, has long been known to participate in several important functions in the vascular bed in support of endothelial cells. These functions include increasing the synthesis and deposition of type IV collagen in the basement membrane, stimulating endothelial proliferation, inhibiting apoptosis, scavenging radical species, and sparing endothelial cell-derived nitric oxide to help modulate blood flow. Although ascorbate may not be able to reverse inflammatory vascular diseases such as atherosclerosis, it may well play a role in preventing the endothelial dysfunction that is the earliest sign of many such diseases. Recent Advances: Beyond simply preventing scurvy, evidence is mounting that ascorbate is required for optimal function of many dioxygenase enzymes in addition to those involved in collagen synthesis. Several of these enzymes regulate the transcription of proteins involved in endothelial function, proliferation, and survival, including hypoxia-inducible factor-1α and histone and DNA demethylases. More recently, ascorbate has been found to acutely tighten the endothelial permeability barrier and, thus, may modulate access of ascorbate and other molecules into tissues and organs. Critical Issues: The issue of the optimal cellular content of ascorbate remains unresolved, but it appears that low millimolar ascorbate concentrations are normal in most animal tissues, in human leukocytes, and probably in the endothelium. Although there may be little benefit of increasing near maximal cellular ascorbate concentrations in normal people, many diseases and conditions have either systemic or localized cellular ascorbate deficiency as a cause for endothelial dysfunction, including early atherosclerosis, sepsis, smoking, and diabetes. Future Directions: A key focus for future studies of ascorbate and the vascular endothelium will likely be to determine the mechanisms and clinical relevance of ascorbate effects on endothelial function, permeability, and survival in diseases that cause endothelial dysfunction. Antioxid. Redox Signal. 19, 2068–2083. PMID:23581713

Vitamins for enhancing plant resistance.

PubMed

Boubakri, Hatem; Gargouri, Mahmoud; Mliki, Ahmed; Brini, Faiçal; Chong, Julie; Jbara, Moez

2016-09-01

This paper provides an overview on vitamins with inducing activities in plants, the molecular and cellular mechanisms implicated, and the hormonal signalling-network regulating this process. Moreover, it reports how vitamins might be part of the molecular events linked to induced resistance by the conventional elicitors. Induced resistance (IR), exploiting the plant innate-defense system is a sustainable strategy for plant disease control. In the last decade, vitamins have been proven to act as inducers of disease resistance, and these findings have received an important attention owing to their safety and cost effectiveness. Vitamins, including thiamine (TH, vitamin B1), riboflavin (RF, vitamin B2), menadione sodium bisulfite (MSB, vitamin K3), Para-aminobenzoic acid (PABA, vitamin Bx), and folic acid (FA, vitamin B9) provided an efficient protection against a wide range of pathogens through the modulation of specific host-defense facets. However, other vitamins, such as ascorbic acid (AA, vitamin C) and tocopherols (vitamin E), have been shown to be a part of the molecular mechanisms associated to IR. The present review is the first to summarize what vitamins are acting as inducers of disease resistance in plants and how could they be modulated by the conventional elicitors. Thus, this report provides an overview on the protective abilities of vitamins and the molecular and cellular mechanisms underlying their activities. Moreover, it describes the hormonal-signalling network regulating vitamin-signal transduction during IR. Finally, a biochemical model describing how vitamins are involved in the establishment of IR process is discussed.

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.

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.

Integrating Introductory Biology and General Chemistry Laboratories.

ERIC Educational Resources Information Center

Godrick, Elizabeth; Hartman, Standish

2000-01-01

Introduces a science laboratory integrating biology and chemistry courses that includes four modules: (1) the fundamental process of reactions; (2) a semester-long project on the chemical assay of ascorbic acid; (3) human metabolism of Vitamin C; and (4) an open-ended project on the manipulation of macromolecules. (YDS)

Effect of chronic hypo and hypervitaminosis C on the brush border enzymes and the intestinal uptake of glucose and alanine.

PubMed

Mahmood, A; Chauhan, V P; Lyall, V; Sarkar, A K

1979-08-15

Brush border sucrase and alkaline phosphatase activities are considerably enhanced in the intestine of ascorbic acid deficient guinea-pigs. Similar increase in the uptake of D-glucose and L-alanine also occurs in chronic vitamin C deficiency. However the permeability of D-glucose and L-alanine in the intestine of animals fed with large doses of vitamin C is severely depressed, with a reduction in the levels of sucrase and alkaline phosphatase activities.

Separation of three water-soluble vitamins by poly(dimethylsiloxane) microchannel electrophoresis with electrochemical detection.

PubMed

Li, Xiang-Yun; Zhang, Qian-Li; Lian, Hong-Zhen; Xu, Jing-Juan; Chen, Hong-Yuan

2007-09-01

A method for rapid separation and sensitive determination of three water-soluble vitamins, pyridoxine, ascorbic acid (VC), and p-aminobenzoic acid (PABA) has been developed by PDMS microchannel electrophoresis integrated with amperometric detection. After treatment of the microchip with oxygen plasma, the peak shapes of the three analytes were essentially improved. Pyridoxine, VC, and PABA were well separated within only 80 s in a running buffer of 20 mM borate solution (pH 8.5). Good linearity was obtained within the concentration range of 2-200 microM for the three water-soluble vitamins. The detection limits were 1.0 microM for pyridoxine and VC, and 1.5 microM for PABA. The proposed method has been successfully applied to real human urine sample, without solid phase extraction, with recoveries of 80-122% for the three water-soluble vitamins.

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.

Vitamin C transporter Slc23a1 links renal reabsorption, vitamin C tissue accumulation, and perinatal survival in mice

PubMed Central

Corpe, Christopher P.; Tu, Hongbin; Eck, Peter; Wang, Jin; Faulhaber-Walter, Robert; Schnermann, Jurgen; Margolis, Sam; Padayatty, Sebastian; Sun, He; Wang, Yaohui; Nussbaum, Robert L.; Espey, Michael Graham; Levine, Mark

2010-01-01

Levels of the necessary nutrient vitamin C (ascorbate) are tightly regulated by intestinal absorption, tissue accumulation, and renal reabsorption and excretion. Ascorbate levels are controlled in part by regulation of transport through at least 2 sodium-dependent transporters: Slc23a1 and Slc23a2 (also known as Svct1 and Svct2, respectively). Previous work indicates that Slc23a2 is essential for viability in mice, but the roles of Slc23a1 for viability and in adult physiology have not been determined. To investigate the contributions of Slc23a1 to plasma and tissue ascorbate concentrations in vivo, we generated Slc23a1–/– mice. Compared with wild-type mice, Slc23a1–/– mice increased ascorbate fractional excretion up to 18-fold. Hepatic portal ascorbate accumulation was nearly abolished, whereas intestinal absorption was marginally affected. Both heterozygous and knockout pups born to Slc23a1–/– dams exhibited approximately 45% perinatal mortality, and this was associated with lower plasma ascorbate concentrations in dams and pups. Perinatal mortality of Slc23a1–/– pups born to Slc23a1–/– dams was prevented by ascorbate supplementation during pregnancy. Taken together, these data indicate that ascorbate provided by the dam influenced perinatal survival. Although Slc23a1–/– mice lost as much as 70% of their ascorbate body stores in urine daily, we observed an unanticipated compensatory increase in ascorbate synthesis. These findings indicate a key role for Slc23a1 in renal ascorbate absorption and perinatal survival and reveal regulation of vitamin C biosynthesis in mice. PMID:20200446

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.

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.

Liposomal-encapsulated Ascorbic Acid: Influence on Vitamin C Bioavailability and Capacity to Protect Against Ischemia–Reperfusion Injury

PubMed Central

Davis, Janelle L.; Paris, Hunter L.; Beals, Joseph W.; Binns, Scott E.; Giordano, Gregory R.; Scalzo, Rebecca L.; Schweder, Melani M.; Blair, Emek; Bell, Christopher

2016-01-01

Intravenous administration of vitamin C has been shown to decrease oxidative stress and, in some instances, improve physiological function in adult humans. Oral vitamin C administration is typically less effective than intravenous, due in part to inferior vitamin C bioavailability. The purpose of this study was to determine the efficacy of oral delivery of vitamin C encapsulated in liposomes. On 4 separate randomly ordered occasions, 11 men and women were administered an oral placebo, or 4 g of vitamin C via oral, oral liposomal, or intravenous delivery. The data indicate that oral delivery of 4 g of vitamin C encapsulated in liposomes (1) produces circulating concentrations of vitamin C that are greater than unencapsulated oral but less than intravenous administration and (2) provides protection from ischemia–reperfusion-mediated oxidative stress that is similar to the protection provided by unencapsulated oral and intravenous administrations. PMID:27375360

Determination of Proximate, Minerals, Vitamin and Anti-Nutrients Composition of Solanum verbascifolium Linn.

NASA Astrophysics Data System (ADS)

Sam, S. M.; Udosen, I. R.; Mensah, S. I.

2012-07-01

The proximate, minerals, vitamins and anti-nutrients composition of Solanum verbascifolium Linn were determined. The proximate composition showed that moisture content was (85.5%), protein was (32.55%), lipid was (2.90%), ash was (7.20%), fibre was (4.80%), carbohydrate was (52.55%) and caloric value was (366.50%) respectively. This was found to be rich in protein and considerably high amount of carbohydrate. The anti-nutrient composition analysis revealed the presence of hydrocyanide (1.39mg/100g), Oxalate (114.40mg/100g), all of which are below toxic level except for oxalic acid. For mineral and vitamin compositions, potassium was significantly (P>0.05) higher than iron, sodium, calcium and phosphorus while vitamin A retinol was (371.72mg/100g) and vitamin C ascorbic acid (39.99mg/100g). Based on these findings the plant is recommended for consumption and for further investigation as a potential raw material for pharmaceutical industry.

Single and combined effects of vitamin C and oregano essential oil in diet, on growth performance, and blood parameters of broiler chicks reared under heat stress condition

NASA Astrophysics Data System (ADS)

Ghazi, Shahab; Amjadian, Tahere; Norouzi, Shokufeh

2015-08-01

This study was conducted to evaluate the effects of adding vitamin C (VC), oregano essential oil (OR), or their combination in diet, on growth performance, and blood parameters of broiler chicks reared under heat stress (HS) condition (38 °C). One-day-old 240 male broilers were randomly assigned to four treatment groups, six replicates of ten birds each. The birds were fed with either a basal diet or a basal diet supplemented with either 200 mg L-ascorbic acid/kg of diet, 250 mg of oregano essential oil/kg of diet, or 200 mg L-ascorbic acid plus 250 mg of oregano essential oil/kg of diet. Average daily feed intake (ADFI), average daily gain (ADG), and feed conversion ratio (FCR) were obtained for 42 days of age and at the end of the experiment (day 42); birds were bled to determine some blood parameters and weighted for final body weight (BW). Feeding birds with diets supplemented with oregano essential oil and vitamin C in a single or combined form increased ADG ( P > 0.05). Also BW increased and feed efficiency decreased ( P < 0.05) in the birds fed with diets including VC and OR (in a single or combined form), compared to those fed the basal diet. ADFI was not significantly influenced by dietary oregano essential oil and vitamin C ( P > 0.05). Supplemental oregano essential oil and vitamin C in a combined form decreased the serum concentration of corticosterone, triglycerides, glucose, and MDA ( P < 0.05) compared with other groups. An increase in the serum concentrations of vitamin C were seen in broiler chicks supplemented with vitamin C. From the results of the present experiment, it can be concluded that diet supplementation by combined oregano essential oil and vitamin C could have beneficial effects on some blood parameters of broiler chicks reared under heat stress condition.

Single and combined effects of vitamin C and oregano essential oil in diet, on growth performance, and blood parameters of broiler chicks reared under heat stress condition.

PubMed

Ghazi, Shahab; Amjadian, Tahere; Norouzi, Shokufeh

2015-08-01

This study was conducted to evaluate the effects of adding vitamin C (VC), oregano essential oil (OR), or their combination in diet, on growth performance, and blood parameters of broiler chicks reared under heat stress (HS) condition (38 °C). One-day-old 240 male broilers were randomly assigned to four treatment groups, six replicates of ten birds each. The birds were fed with either a basal diet or a basal diet supplemented with either 200 mg L-ascorbic acid/kg of diet, 250 mg of oregano essential oil/kg of diet, or 200 mg L-ascorbic acid plus 250 mg of oregano essential oil/kg of diet. Average daily feed intake (ADFI), average daily gain (ADG), and feed conversion ratio (FCR) were obtained for 42 days of age and at the end of the experiment (day 42); birds were bled to determine some blood parameters and weighted for final body weight (BW). Feeding birds with diets supplemented with oregano essential oil and vitamin C in a single or combined form increased ADG (P > 0.05). Also BW increased and feed efficiency decreased (P < 0.05) in the birds fed with diets including VC and OR (in a single or combined form), compared to those fed the basal diet. ADFI was not significantly influenced by dietary oregano essential oil and vitamin C (P > 0.05). Supplemental oregano essential oil and vitamin C in a combined form decreased the serum concentration of corticosterone, triglycerides, glucose, and MDA (P < 0.05) compared with other groups. An increase in the serum concentrations of vitamin C were seen in broiler chicks supplemented with vitamin C. From the results of the present experiment, it can be concluded that diet supplementation by combined oregano essential oil and vitamin C could have beneficial effects on some blood parameters of broiler chicks reared under heat stress condition.

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. Ascorbic Acid and Sodium Ascorbate acted as a nitrosation inhibitor in several food and cosmetic product studies. No compound-related clinical signs or gross or microscopic pathological effects were observed in either mice, rats, or guinea pigs in short-term studies. Male guinea pigs fed a control basal diet and given up to 250 mg Ascorbic Acid orally for 20 weeks had similar hemoglobin, blood glucose, serum iron, liver iron, and liver glycogen levels compared to control values. Male and female F344/N rats and B6C3F(1) mice were fed diets containing up to 100,000 ppm Ascorbic Acid for 13 weeks with little toxicity. Chronic Ascorbic Acid feeding studies showed toxic effects at dosages above 25 mg/kg body weight (bw) in rats and guinea pigs. Groups of male and female rats given daily doses up to 2000 mg/kg bw Ascorbic Acid for 2 years had no macro- or microscopically detectable toxic lesions. Mice given Ascorbic Acid subcutaneous and intravenous daily doses (500 to 1000 mg/kg bw) for 7 days had no changes in appetite, weight gain, and general behavior; and histological examination of various organs showed no changes. Ascorbic Acid was a photoprotectant when applied to mice and pig skin before exposure to ultraviolet (UV) radiation. The inhibition of UV-induced suppression of contact hypersensitivity was also noted. Magnesium Ascorbyl Phosphate administration immediately after exposure in hairless mice significantly delayed skin tumor formation and hyperplasia induced by chronic exposure to UV radiation. Pregnant mice and rats were given daily oral doses of Ascorbic Acid up to 1000 mg/kg bw with no indications of adult-toxic, teratogenic, or fetotoxic effects. Ascorbic Acid and Sodium Ascorbate were not genotoxic in several bacterial and mammalian test systems, consistent with the antioxidant properties of these chemicals. In the presence of certain enzyme systems or metal ions, evidence of genotoxicity was seen. The National Toxicology Program (NTP) conducted a 2-year oral carcinogenesis bioassay of Ascorbic Acid (25,000 and 50,000 ppm) in F344/N rats and B6C3F(1) mice. Ascorbic Acid was not carcinogenic in either sex of both rats and mice. Inhibition of carcinogenesis and tumor growth related to Ascorbic Acid's antioxidant properties has been reported. Sodium Ascorbate has been shown to promote the development of urinary carcinomas in two-stage carcinogenesis studies. Dermal application of Ascorbic Acid to patients with radiation dermatitis and burn victims had no adverse effects. Ascorbic Acid was a photoprotectant in clinical human UV studies at doses well above the minimal erythema dose (MED). An opaque cream containing 5% Ascorbic Acid did not induce dermal sensitization in 103 human subjects. A product containing 10% Ascorbic Acid was nonirritant in a 4-day minicumulative patch assay on human skin and a facial treatment containing 10% Ascorbic Acid was not a contact sensitizer in a maximization assay on 26 humans. Because of the structural and functional similarities of these ingredients, the Panel believes that the data on one ingredient can be extrapolated to all of them. The Expert Panel attributed the finding that Ascorbic Acid was genotoxic in these few assay systems due to the presence of other chemicals, e.g., metals, or certain enzyme systems, which effectively convert Ascorbic Acid's antioxidant action to that of a pro-oxidant. When Ascorbic Acid acts as an antioxidant, the Panel concluded that Ascorbic Acid is not genotoxic. Supporting this view were the carcinogenicity studies conducted by the NTP, which demonstrated no evidence of carcinogenicity. Ascorbic Acid was found to effectively inhibit nitrosamine yield in several test systems. The Panel did review studies in which Sodium Ascorbate acted as a tumor promoter in animals. These results were considered to be related to the concentration of sodium ions and the pH of urine in the test animals. Similar effects were seen with sodium bicarbonate. Because of the concern that certain metal ions may combine with these ingredients to produce pro-oxidant activity, the Panel cautioned formulators to be certain that these ingredients are acting as antioxidants in cosmetic formulations. The Panel believed that the clinical experience in which Ascorbic Acid was used on damaged skin with no adverse effects and the repeat-insult patch test (RIPT) using 5% Ascorbic Acid with negative results supports the finding that this group of ingredients does not present a risk of skin sensitization. These data coupled with an absence of reports in the clinical literature of Ascorbic Acid sensitization strongly support the safety of these ingredients.

Computational Study of the Bulk Properties of a Novel Molecule: alpha-Tocopherol-Ascorbic Acid Surfactant

NASA Astrophysics Data System (ADS)

Stirling, Shannon; Kim, Hye-Young

Alpha-tocopherol-ascorbic acid surfactant (EC) is a novel amphiphilic molecule of antioxidant properties, which has a hydrophobic vitamin E and a hydrophilic vitamin C chemically linked. We have developed atomistic force fields (g54a7) for a protonated (neutral) EC molecule. Our goal is to carry out molecular dynamics (MD) simulations of protonated EC molecules using the newly developed force fields and study the molecular properties. First we ran energy minimization (EM) with one molecule in a vacuum to obtain the low energy molecular configuration with emtol =10. We then used Packmol to insert 125 EC molecules in a 3nm cube. We then performed MD simulations of the bulk system composed of 125 EC molecules, from which we measured the bulk density and the evaporation energy of the molecular system. Gromacs2016 is used for the EM and MD simulation studies. We will present the results of the ongoing research. National Institute Of General Medical Sciences of the National Institutes of Health under Award Number P20GM103424 (Kim). Computational resources were provided by the Louisiana Optical Network Initiative.

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.

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

Vitamin C-sulfate inhibits mineralization in chondrocyte cultures: a caveat

NASA Technical Reports Server (NTRS)

Boskey, A. L.; Blank, R. D.; Doty, S. B.

2001-01-01

Differentiating chick limb-bud mesenchymal cell micro-mass cultures routinely mineralize in the presence of 10% fetal calf serum, antibiotics, 4 mM inorganic phosphate (or 2.5 mM beta-glycerophosphate), 0.3 mg/ml glutamine and either 25 microg/ml vitamin C or 5-12 microg/ml vitamin C-sulfate. The failure of these cultures to produce a mineralized matrix (assessed by electron microscopy, 45Ca uptake and Fourier transform infrared microscopy) led to the evaluation of each of these additives. We report here that the "stable" vitamin C-sulfate (ascorbic acid-2-sulfate) causes increased sulfate incorporation into the cartilage matrix. Furthermore, the release of sulfate from the vitamin C derivative appears to be responsible for the inhibition of mineral deposition, as demonstrated in cultures with equimolar amounts of vitamin C and sodium sulfate.

Effects of dietary addition of vitamins C and D3 on growth and calcium and phosphorus content of pond-cultured channel catfish

USGS Publications Warehouse

Launer, C.A.; Tiemeier, O.W.; Deyoe, C.W.

1978-01-01

Fingerling channel catfish, Ictalurus punctatus, were fed one of three diets: one deficient in vitamin C (ascorbic acid), one deficient in vitamin D3 (cholecalciferol), or one containing both vitamins. Semimonthly from May to September and monthly from September to February, calcium and phosphorus were determined in eviscerated bodies and fat-free skeletons by neutron activation analysis. Body weight gains, survival rate, and feed conversion rates were determined for the May to September period. Fish on the three diet regimens showed no significant difference in weight gain, feed conversion, or survival. Interactions between sampling date and diet indicated no correlation between vitamin C or D3 and the calcium and phosphorus in eviscerated bodies and fat-free skeletons of the fish.

Dehydroascorbic Acid Promotes Cell Death in Neurons Under Oxidative Stress: a Protective Role for Astrocytes.

PubMed

García-Krauss, Andrea; Ferrada, Luciano; Astuya, Allisson; Salazar, Katterine; Cisternas, Pedro; Martínez, Fernando; Ramírez, Eder; Nualart, Francisco

2016-11-01

Ascorbic acid (AA), the reduced form of vitamin C, is incorporated into neurons via the sodium ascorbate co-transporter SVCT2. However, this transporter is not expressed in astrocytes, which take up the oxidized form of vitamin C, dehydroascorbic acid (DHA), via the facilitative hexose transporter GLUT1. Therefore, neuron and astrocyte interactions are thought to mediate vitamin C recycling in the nervous system. Although astrocytes are essential for the antioxidant defense of neurons under oxidative stress, a condition in which a large amount of ROS is generated that may favor the extracellular oxidation of AA and the subsequent neuronal uptake of DHA via GLUT3, potentially increasing oxidative stress in neurons. This study analyzed the effects of oxidative stress and DHA uptake on neuronal cell death in vitro. Different analyses revealed the presence of the DHA transporters GLUT1 and GLUT3 in Neuro2a and HN33.11 cells and in cortical neurons. Kinetic analyses confirmed that all cells analyzed in this study possess functional GLUTs that take up 2-deoxyglucose and DHA. Thus, DHA promotes the death of stressed neuronal cells, which is reversed by incubating the cells with cytochalasin B, an inhibitor of DHA uptake by GLUT1 and GLUT3. Additionally, the presence of glial cells (U87 and astrocytes), which promote DHA recycling, reverses the observed cell death of stressed neurons. Taken together, these results indicate that DHA promotes the death of stressed neurons and that astrocytes are essential for the antioxidative defense of neurons. Thus, the astrocyte-neuron interaction may function as an essential mechanism for vitamin C recycling, participating in the antioxidative defense of the brain.

Histological and histochemical studies on the female reproductive system of rose-ringed parakeet (Psittacula krameri) after testosterone propionate treatment.

PubMed

Sarker, A K; Seth, T N

1975-01-01

Intramuscular injections of testosterone propionate (Perandren, CIBA) at a dose level of 2.5 mg per day for 10 days into adult female parakeet caused an increment of differentiated follicles in the ovary. The histological study of the testosterone treated oviduct of the bird showed well developed villi with a significant number of tubular glands particularly in the middle and distal parts of the oviduct. The high level of alkaline phosphatase activity and ascorbic acid concentration in the distal part of the oviduct in treated birds probably increase the power of hatchable eggs which has a close relationship with the enzyme and vitamin C concentration in the uterus. The testosterone treatment causes a marked depletion of granulosal vitamins from ovary but augments the ascorbate mobilization in the thecal region to a very great extent probably due to more LH secretion from the pituitary.

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.

Effect of ascorbic acid (vitamin C) on the ESR spectra of the red and black hair: pheomelanin free radicals are not always present in red hair.

PubMed

Chikvaidze, Eduard; Topeshashvili, Maia

2015-12-01

Increased incidence of melanoma in the population with red hair is conditioned by synthesis of pheomelanin pigments in the skin and their phototoxic properties. The recent research has shown that free radicals of pheomelanin are produced not only by the influence of UV irradiation, but also in UV-independent pathways of oxidative stress. It has been ascertained, that the color of the hair is not always determinant of the amount of pheolemanin radicals in red hair. Therefore, in order to evaluate the risk of melanoma in different individuals, it is necessary to define the amount of free radicals of pheomelanin in red hair using ESR spectroscopy method. Besides, it is very important to find effective antioxidant, capable of neutralizing free radicals of pheomelanin. It was proved that ascorbic acid neutralizes free radicals of pheomelanin very effectively. The main goal of our research was to define the presumably optimal concentration of ascorbic acid as an antioxidant and study the kinetics of the influence of this concentration on red and black hair. It has been found out, that ascorbic acid influences the free radicals of red and black hair, and its appropriate optimal concentration is 10 mM. The obtained results can be considered in dermatology and cosmetology. Copyright © 2015 John Wiley & Sons, Ltd.

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.

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 human blood. Microbiological tests were carried out to indicate the microbiological sensitivity of obtained PURs. Results of performed studies showed that obtained AA-modified PUR materials may find an application in soft tissue regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessment of vitamin and carotenoid concentrations of emerging food products: edible microgreens.

PubMed

Xiao, Zhenlei; Lester, Gene E; Luo, Yaguang; Wang, Qin

2012-08-08

Microgreens (seedlings of edible vegetables and herbs) have gained popularity as a new culinary trend over the past few years. Although small in size, microgreens can provide surprisingly intense flavors, vivid colors, and crisp textures and can be served as an edible garnish or a new salad ingredient. However, no scientific data are currently available on the nutritional content of microgreens. The present study was conducted to determine the concentrations of ascorbic acid, carotenoids, phylloquinone, and tocopherols in 25 commercially available microgreens. Results showed that different microgreens provided extremely varying amounts of vitamins and carotenoids. Total ascorbic acid contents ranged from 20.4 to 147.0 mg per 100 g fresh weight (FW), while β-carotene, lutein/zeaxanthin, and violaxanthin concentrations ranged from 0.6 to 12.1, 1.3 to 10.1, and 0.9 to 7.7 mg/100 g FW, respectively. Phylloquinone level varied from 0.6 to 4.1 μg/g FW; meanwhile, α-tocopherol and γ-tocopherol ranged from 4.9 to 87.4 and 3.0 to 39.4 mg/100 g FW, respectively. Among the 25 microgreens assayed, red cabbage, cilantro, garnet amaranth, and green daikon radish had the highest concentrations of ascorbic acids, carotenoids, phylloquinone, and tocopherols, respectively. In comparison with nutritional concentrations in mature leaves (USDA National Nutrient Database), the microgreen cotyledon leaves possessed higher nutritional densities. The phytonutrient data may provide a scientific basis for evaluating nutritional values of microgreens and contribute to food composition database. These data also may be used as a reference for health agencies' recommendations and consumers' choices of fresh vegetables.

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.

GDP-D-mannose epimerase regulates male gametophyte development, plant growth and leaf senescence in Arabidopsis.

PubMed

Qi, Tiancong; Liu, Zhipeng; Fan, Meng; Chen, Yan; Tian, Haixia; Wu, Dewei; Gao, Hua; Ren, Chunmei; Song, Susheng; Xie, Daoxin

2017-09-04

Plant GDP-D-mannose epimerase (GME) converts GDP-D-mannose to GDP-L-galactose, a precursor of both L-ascorbate (vitamin C) and cell wall polysaccharides. However, the genetic functions of GME in Arabidopsis are unclear. In this study, we found that mutations in Arabidopsis GME affect pollen germination, pollen tube elongation, and transmission and development of the male gametophyte through analysis of the heterozygous GME/gme plants and the homozygous gme plants. Arabidopsis gme mutants also exhibit severe growth defects and early leaf senescence. Surprisingly, the defects in male gametophyte in the gme plants are not restored by L-ascorbate, boric acid or GDP-L-galactose, though boric acid rescues the growth defects of the mutants, indicating that GME may regulate male gametophyte development independent of L-ascorbate and GDP-L-galactose. These results reveal key roles for Arabidopsis GME in reproductive development, vegetative growth and leaf senescence, and suggest that GME regulates plant growth and controls male gametophyte development in different manners.

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

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.

Influence of cold stress on contents of soluble sugars, vitamin C and free amino acids including gamma-aminobutyric acid (GABA) in spinach (Spinacia oleracea).

PubMed

Yoon, Young-Eun; Kuppusamy, Saranya; Cho, Kye Man; Kim, Pil Joo; Kwack, Yong-Bum; Lee, Yong Bok

2017-01-15

The contents of soluble sugars (sucrose, fructose, glucose, maltose and raffinose), vitamin C and free amino acids (34 compounds, essential and non-essential) were quantified in open-field and greenhouse-grown spinaches in response to cold stress using liquid chromatography. In general, greenhouse cultivation produced nutritionally high value spinach in a shorter growing period, where the soluble sugars, vitamin C and total amino acids concentrations, including essential were in larger amounts compared to those grown in open-field scenarios. Further, low temperature exposure of spinach during a shorter growth period resulted in the production of spinach with high sucrose, ascorbate, proline, gamma-aminobutyric acid, valine and leucine content, and these constitute the most important energy/nutrient sources. In conclusion, cultivation of spinach in greenhouse at a low temperature (4-7°C) and exposure for a shorter period (7-21days) before harvest is recommended. This strategy will produce a high quality product that people can eat. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of gamma radiation on sugars and vitamin C: Radiolytic pathways.

PubMed

Ramírez-Cahero, Hiram F; Valdivia-López, Ma Angeles

2018-04-15

The radiolytic decomposition of glucose, fructose, sucrose, ascorbic acid (H 2 A) and dehydroascorbic acid (DHAA), induced by ionizing radiation, was investigated. Aqueous solutions of these compounds were gamma-irradiated at doses of 0.5, 0.7 and 1 kGy, with a dose rate of 0.04 kGy/min, in the presence of air, followed by HPLC, HPLC-MS, EPR, and UV-VIS spectroscopy analysis of the resulting mixtures. Carboxylic acids, 2-furaldehyde, 5-hydroxymethyl-2-furaldehyde, furfuryl alcohol, 2-furoic acid and 2(5H)-furanone were identified in solutions of sugars and vitamin C, by comparing with standards. EPR studies exhibited a higher amount of free radicals for fructose than the other sugars, and more for DHAA than H 2 A. Additionally, spectroscopic determinations showed a typical UV-VIS absorption for furans during the storage of irradiated solutions. Formation and decomposition routes for furanoids and aliphatic carboxylic acids, and mechanistic pathways for the radiolytic induced rupture of glucose, fructose, sucrose and vitamin C have been proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Studying Current-Potential Curves Using a Bipotentiometric Lodometric Back-Titration for the Determination of Ascorbic Acid in Fruits and Vegetables

ERIC Educational Resources Information Center

Verdini, Roxana A.; Lagier, Claudia M.

2004-01-01

Voltammetry principles are introduced to students by means of a bipotentiometric method to determine vitamin C in fruits and vegetables. The aim is to draw attention to voltammetric methods, particular to the study of current-potential curves, stressing the potential applicability in areas of food quality control.

Evaluation of vitamins A, C and E content in diets of adolescents living in Warsaw, Poland.

PubMed

Dybkowska, Ewa; Waszkiewicz-Robak, Bozena; Piekot, Edyta

2014-01-01

Antioxidant vitamins such as alpha-tocopherol (vitamin E), ascorbic acid (vitamin C), and beta-carotene (provitamin A), play a significant role in protecting the body from an excess of free radicals. The vitamin content of the diet is thus very important. To assess whether the dietary intake of vitamins A, C and E is adequate in a selected group of adolescents living in Warsaw. The mean vitamin consumption was estimated using three-day dietary records whilst vitamin contents of selected foodstuffs were obtained from Food Composition Tables. Both were related to Polish nutrition standards applied to adolescents; i.e. EAR (Estimated Average Requirement) for vitamins A and C and AI (Adequate Intake) for vitamin E. Dietary vitamin C in adolescents and vitamin E in girls were around 18-25% lower than that recommended. Diets that were deficient in vitamins C and E were recorded in 47% to 67% adolescents. It is therefore necessary to increase the consumption of vegetables and fruit which provide a valuable dietary source for these vitamins.

Evaluation of three pumpkin species: correlation with physicochemical, antioxidant properties and classification using SPME-GC-MS and E-nose methods.

PubMed

Zhou, Chun-Li; Mi, Li; Hu, Xue-Yan; Zhu, Bi-Hua

2017-09-01

To ascertain the most discriminant variables for three pumpkin species principal component analysis (PCA) was performed. Twenty-four parameters (pH, conductivity, sucrose, glucose, total soluble solids, L* , a* , b* , individual weight, edible rate, firmness, citric acid, fumaric acid, l-ascorbic acid, malic acid, PPO activity, POD activity, total flavonoids, vitamin E, total phenolics, DPPH, FRAP, β-carotene, and aroma) were considered. The studied pumpkin species were Cucurbita maxima , Cucurbita moschata , and Cucurbita pepo . Three pumpkin species were classified by PCA based on aroma, physicochemical and antioxidant properties because the sum of PC1 and PC2 were both greater than 85% (85.06 and 93.64% respectively). Results were validated by the PCA and showed that PPO activity, total flavonoid, sucrose, glucose, TSS, a* , pH, malic acid, vitamin E, DPPH, FRAP and β-carotene, and aroma are highly useful parameters to classify pumpkin species.

Concentration-Dependence of Vitamin C in Combinations with Vitamin E and Zeaxanthin on Light-Induced Toxicity to Retinal Pigment Epithelial Cells†

PubMed Central

Różanowska, Małgorzata; Bakker, Linda; Boulton, Michael E.; Różanowski, Bartosz

2012-01-01

The purpose of this study was to determine the effects of increasing concentration of ascorbate alone and in combinations with α-tocopherol and zeaxanthin on phototoxicity to the retinal pigment epithelium. ARPE-19 cells were exposed to rose bengal and visible light in the presence and absence of antioxidants. Toxicity was quantified by an assay of cell reductive activity. 20 min exposure to visible light and photosensitizer decreased cell viability to ~42%. Lipophilic antioxidants increased viabilities to ~70%, ~61% and ~75% for α-tocopherol, zeaxanthin and their combination, respectively. Cell viabilities were ~70%, 56% and 5% after exposures in the presence of 0.35, 0.7 and 1.4 mM ascorbate, respectively. 45 min exposure increased cell death to ~74% and to >95% in the absence and presence of ascorbate, respectively. In the presence of ascorbate, zeaxanthin did not significantly affect phototoxicity. α-Tocopherol and its combination with zeaxanthin enhanced protective effects of ascorbate but did not prevent from ascorbate-mediated deleterious effects. In conclusion, there is a narrow range of concentrations and exposure times where ascorbate exerts photoprotective effects, exceeding which leads to ascorbate-mediated increase in photocytotoxicity. Vitamin E and its combination with zeaxanthin can enhance protective effects of ascorbate but do not ameliorate its deleterious effects. PMID:22924673

Microchannel emulsification: A promising technique towards encapsulation of functional compounds.

PubMed

Khalid, Nauman; Kobayashi, Isao; Neves, Marcos A; Uemura, Kunihiko; Nakajima, Mitsutoshi

2017-06-13

This review provides an overview of microchannel emulsification (MCE) for production of functional monodispersed emulsion droplets. The main emphasis has been put on functional bioactives encapsulation using grooved-type and straight-through microchannel array plates. MCE successfully encapsulates the bioactives like β-carotene, oleuropein, γ-oryzanol, β-sitosterol, L-ascorbic acid and ascorbic acid derivatives, vitamin D and quercetin. These bioactives were encapsulated in a variety of delivery systems like simple and multiple emulsions, polymeric particles, microgels, solid lipid particles and functional vesicles. The droplet generation process in MCE is based upon spontaneous transformation of interfaces rather than high energy shear stress systems. The scale-up of MCE can increase the productivity of monodispersed droplets >100 L h -1 and makes it a promising tool at industrial level.

Association of vitamin C with the risk of age-related cataract: a meta-analysis.

PubMed

Wei, Lin; Liang, Ge; Cai, Chunmei; Lv, Jin

2016-05-01

Whether vitamin C is a protective factor for age-related cataract remains unclear. Thus, we conducted a meta-analysis to summarize the evidence from epidemiological studies of vitamin C and the risk of age-related cataract. Pertinent studies were identified by searching in PubMed and in Webscience. The random effect model was used to combine the results. Meta-regression and subgroups analyses were used to explore potential sources of between-study heterogeneity. Publication bias was estimated using Egger's regression asymmetry test. Finally, 15 articles with 20 studies for vitamin C intake and eight articles with 10 studies for serum ascorbate were included in this meta-analysis. The relative risk (RR) and 95% confidence interval of cataract for the highest versus the lowest category of vitamin C intake was 0.814 (0.707-0.938), and the associations were significant in America and Asia. Significant association of cataract risk with highest versus the lowest category of serum ascorbate was found in general [0.704 (0.564-0.879)]. Inverse associations were also found between serum ascorbate and nuclear cataract and posterior subcapsular cataract. Higher vitamin C intake and serum ascorbate might be inversely associated with risk of cataract. Vitamin C intake should be advocated for the primary prevention of cataract. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Antioxidant nutrients in plasma of Japanese patients with chronic obstructive pulmonary disease, asthma-COPD overlap syndrome and bronchial asthma.

PubMed

Kodama, Yuzo; Kishimoto, Yuki; Muramatsu, Yoko; Tatebe, Junko; Yamamoto, Yu; Hirota, Nao; Itoigawa, Yukinari; Atsuta, Ryo; Koike, Kengo; Sato, Tadashi; Aizawa, Koich; Takahashi, Kazuhisa; Morita, Toshisuke; Homma, Sakae; Seyama, Kuniaki; Ishigami, Akihito

2017-11-01

Few studies to date have investigated the antioxidant nutrients such as vitamin C (ascorbic acid), vitamin E (α-tocopherol), retinol and carotenoids in plasma from patients with pulmonary disease in Japan. To clarify the role of antioxidant nutrients such as vitamin C, vitamin E, retinol and various carotenoids in plasma of Japanese patients with chronic obstructive lung diseases (COPD), asthma-COPD overlap syndrome (ACOS) and/or bronchial asthma (BA), we compared to healthy elderly controls. Ascorbic acid (AA), carotenoids (lutein, zeaxanthin, β-cryptoxanthin, α-carotene, β-carotene and lycopene), retinol and α-tocopherol levels in plasma were determined by using a high performance liquid chromatography. Reduced glutathione (GSH), oxidised glutathione (GSSG) in whole blood and urinary 8-OHdG were also determined. Plasma AA level of COPD subjects was significantly lower than that of healthy elderly people. Conversely, ACOS and BA subjects showed no significant difference from healthy elderly people. Moreover, plasma lycopene and total carotenoid levels and GSH content in blood were significantly lower in COPD subjects than these in healthy elderly people. However, other redox markers such as GSSG, GSH/GSSG ratio and urinary 8-OHdG found no significant differences between COPD, ACOS and BA compared to healthy elderly people. These results suggested that COPD of Japanese patients may develop partly because of oxidative stress derived from a shortage of antioxidant nutrients, especially of AA and lycopene, as well as GSH while this may not be the case in both ACOS and BA. © 2016 John Wiley & Sons Ltd.

The effect of bleaching agents on the degradation of vitamins and carotenoids in spray-dried whey protein concentrate.

PubMed

Stout, M A; Park, C W; Drake, M A

2017-10-01

Previous research has shown that bleaching affects flavor and functionality of whey proteins. The role of different bleaching agents on vitamin and carotenoid degradation is unknown. The objective of this study was to determine the effects of bleaching whey with traditional annatto (norbixin) by hydrogen peroxide (HP), benzoyl peroxide (BP), or native lactoperoxidase (LP) on vitamin and carotenoid degradation in spray-dried whey protein concentrate 80% protein (WPC80). An alternative colorant was also evaluated. Cheddar whey colored with annatto (15 mL/454 L of milk) was manufactured, pasteurized, and fat separated and then assigned to bleaching treatments of 250 mg/kg HP, 50 mg/kg BP, or 20 mg/kg HP (LP system) at 50°C for 1 h. In addition to a control (whey with norbixin, whey from cheese milk with an alternative colorant (AltC) was evaluated. The control and AltC wheys were also heated to 50°C for 1 h. Wheys were concentrated to 80% protein by ultrafiltration and spray dried. The experiment was replicated in triplicate. Samples were taken after initial milk pasteurization, initial whey formation, after fat separation, after whey pasteurization, after bleaching, and after spray drying for vitamin and carotenoid analyses. Concentrations of retinol, a-tocopherol, water-soluble vitamins, norbixin, and other carotenoids were determined by HPLC, and volatile compounds were measured by gas chromatography-mass spectrometry. Sensory attributes of the rehydrated WPC80 were documented by a trained panel. After chemical or enzymatic bleaching, WPC80 displayed 7.0 to 33.3% reductions in retinol, β-carotene, ascorbic acid, thiamin, α-carotene, and α-tocopherol. The WPC80 bleached with BP contained significantly less of these compounds than the HP- or LP-bleached WPC80. Riboflavin, pantothenic acid, pyridoxine, nicotinic acid, and cobalamin concentrations in fluid whey were not affected by bleaching. Fat-soluble vitamins were reduced in all wheys by more than 90% following curd formation and fat separation. With the exception of cobalamin and ascorbic acid, water-soluble vitamins were reduced by less than 20% throughout processing. Norbixin destruction, volatile compound, and sensory results were consistent with previous studies on bleached WPC80. The WPC80 colored with AltC had a similar sensory profile, volatile compound profile, and vitamin concentration as the control WPC80. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Chemical composition of rosehips from different Rosa species: an alternative source of antioxidants for the food industry.

PubMed

Jiménez, Sandra; Jiménez-Moreno, Nerea; Luquin, Asunción; Laguna, Mariano; Rodríguez-Yoldi, María Jesús; Ancín-Azpilicueta, Carmen

2017-07-01

It is important to explore new sources of natural additives because the demand for these compounds by consumers is increasing. These products also provide health benefits and help in food preservation. An unexplored source of nutrients and antioxidant compounds is rosehip, the fleshy fruit of roses. This work compares the antioxidant compound (vitamin C, neutral phenols and acidic phenols) content of four Rosa species rosehips: R. pouzinii, R. corymbifera, R. glauca and R. canina from different geographical zones. Results show quantitative variability in ascorbic acids and neutral phenols content, and quantitative and qualitative differences in acidic phenol content, depending on species. Vitamin C concentration was highly variable depending on species, R. canina being the one with the highest concentration and R. pouzinii the one with the lowest content. Variability was found in total neutral polyphenols concentration and a correlation between freshness of the rosehips and concentration of neutral polyphenols was also found. Significant differences were found in the acidic phenols content among the studied species. Generally antioxidant activity was higher in the vitamin C fraction.

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

Proximate composition and mineral content of two edible species of Cnidoscolus (tree spinach).

PubMed

Kuti, J O; Kuti, H O

1999-01-01

Proximate composition and mineral content of raw and cooked leaves of two edible tree spinach species (Cnidoscolus chayamansa and C. aconitifolius), known locally as 'chaya', were determined and compared with that of a traditional green vegetable, spinach (Spinicia oleraceae). Results of the study indicated that the edible leafy parts of the two chaya species contained significantly (p<0.05) greater amounts of crude protein, crude fiber, Ca, K, Fe, ascorbic acid and beta-carotene than the spinach leaf. However, no significant (p>0.05) differences were found in nutritional composition and mineral content between the chaya species, except minor differences in the relative composition of fatty acids, protein and amino acids. Cooking of chaya leaves slightly reduced nutritional composition of both chaya species. Cooking is essential prior to consumption to inactivate the toxic hydrocyanic glycosides present in chaya leaves. Based on the results of this study, the edible chaya leaves may be good dietary sources of minerals (Ca, K and Fe) and vitamins (ascorbic acid and beta-carotene).

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

PubMed Central

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

2013-01-01

The aim of this study was to examine the contribution of sugar, organic acid, neutral phenol, and anthocyanin fractions and added ascorbic acid to grape and pomegranate-nectarine juice total phenol, ORAC, FRAP, and DPPH values. Neutral phenol and anthocyanin fractions contributed ≥75% of the total antioxidant capacity (TAC) for both juices. Intrinsic synergy and antagonism among the fractionated constituents occurred inconsistently in each assay. Sugars and organic acids antagonized pomegranate juice neutral phenols and anthocyanins in the DPPH assay by 50% and the grape juice ORAC value by 21%, but were synergistic to the grape juice FRAP value. The added ascorbic acid was dose-dependently synergistic with pomegranate and grape juice total phenol, DPPH, and FRAP assays, but less so in the ORAC assay. Thus, the interactions between grape and pomegranate juice constituents determine TAC and total phenol values, and synergy in these assays could not be attributed solely to polyphenols. PMID:24187439

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 < 0.02 for rs12479919. The β coefficients for the regression of log10 plasma ascorbate on aqueous humor ascorbate were higher for the GG genotype of rs6596473: GG, β = 1460 compared to carriage of the C allele, CG, β = 1059, CC, β = 1132, p interaction = 0.1. In conclusion we found that compared to studies in well-nourished populations, ascorbate concentrations in the plasma, aqueous humor and lens nucleus were low. We present novel findings that polymorphisms in SLC23A1/2 genes influenced ascorbate concentration in aqueous humor and lens nucleus. Copyright © 2014 Elsevier Ltd. All rights reserved.

A combination of ascorbic acid and α-tocopherol to test the effectiveness and safety in the fragile X syndrome: study protocol for a phase II, randomized, placebo-controlled trial.

PubMed

de Diego-Otero, Yolanda; Calvo-Medina, Rocio; Quintero-Navarro, Carolina; Sánchez-Salido, Lourdes; García-Guirado, Francisco; del Arco-Herrera, Ignacio; Fernández-Carvajal, Isabel; Ferrando-Lucas, Teresa; Caballero-Andaluz, Rafaela; Pérez-Costillas, Lucia

2014-09-03

Fragile X syndrome (FXS) is an inherited neurodevelopmental condition characterised by behavioural, learning disabilities, physical and neurological symptoms. In addition, an important degree of comorbidity with autism is also present. Considered a rare disorder affecting both genders, it first becomes apparent during childhood with displays of language delay and behavioural symptoms.Main aim: To show whether the combination of 10 mg/kg/day of ascorbic acid (vitamin C) and 10 mg/kg/day of α-tocopherol (vitamin E) reduces FXS symptoms among male patients ages 6 to 18 years compared to placebo treatment, as measured on the standardized rating scales at baseline, and after 12 and 24 weeks of treatment.Secondary aims: To assess the safety of the treatment. To describe behavioural and cognitive changes revealed by the Developmental Behaviour Checklist Short Form (DBC-P24) and the Wechsler Intelligence Scale for Children-Revised. To describe metabolic changes revealed by blood analysis. To measure treatment impact at home and in an academic environment. A phase II randomized, double-blind pilot clinical trial. male children and adolescents diagnosed with FXS, in accordance with a standardized molecular biology test, who met all the inclusion criteria and none of the exclusion criteria. clinical data, blood analysis, Wechsler Intelligence Scale for Children-Revised, Conners parent and teacher rating scale scores and the DBC-P24 results will be obtained at the baseline (t0). Follow up examinations will take place at 12 weeks (t1) and 24 weeks (t2) of treatment. A limited number of clinical trials have been carried out on children with FXS, but more are necessary as current treatment possibilities are insufficient and often provoke side effects. In the present study, we sought to overcome possible methodological problems by conducting a phase II pilot study in order to calculate the relevant statistical parameters and determine the safety of the proposed treatment. The results will provide evidence to improve hyperactivity control and reduce behavioural and learning problems using ascorbic acid (vitamin C) and α-tocopherol (vitamin E). The study protocol was approved by the Regional Government Committee for Clinical Trials in Andalusia and the Spanish agency for drugs and health products. ClinicalTrials.gov Identifier: NCT01329770 (29 March 2011).

Inhibition of proteases and phospholipases A2 from Bothrops atrox and Crotalus durissus terrificus snake venoms by ascorbic acid, vitamin E, and B-complex vitamins.

PubMed

Oliveira, Carlos H M; Simão, Anderson A; Trento, Marcus V C; César, Pedro H S; Marcussi, Silvana

2016-01-01

The enzyme inhibition by natural and/ or low-cost compounds may represent a valuable adjunct to traditional serotherapy performed in cases of snakebite, mainly with a view to mitigate the local effects of envenoming. The objective of this study was to evaluate possible interactions between vitamins and enzymes that comprise Bothrops atrox and Crotalus durissus terrificus venoms, in vitro. Proteolysis inhibition assays (substrates: azocasein, collagen, gelatin and fibrinogen), hemolysis, coagulation, hemagglutination were carried out using different proportions of vitamins in face of to inhibit minimum effective dose of each venom. The vitamins were responsible for reducing 100% of breaking azocasein by C.d.t. venom, thrombolysis induced by B. atrox and fibrinogenolysis induced by both venoms. It is suggested the presence of interactions between vitamin and the active site of enzymes, for example the interactions between hydrophobic regions present in the enzymes and vitamin E, as well as the inhibitions exercised by antioxidant mechanism.

Antioxidant capacity and vitamin E in barley: Effect of genotype and storage.

PubMed

Do, Thu Dung T; Cozzolino, Daniel; Muhlhausler, Beverly; Box, Amanda; Able, Amanda J

2015-11-15

Antioxidants, including vitamin E, may have a positive effect on human health and prolong storage of food items. Vitamin E content and antioxidant capacity were measured in 25 barley genotypes before and after 4 months storage at 10 °C using high performance liquid chromatography (HPLC) and ability to scavenge DPPH radicals, respectively. As expected, α-tocotrienol (α-T3) and α-tocopherol (α-T) were the predominant tocol isomers. Vitamin E content and antioxidant capacity varied significantly among genotypes. Vitamin E ranged from 8.5 to 31.5 μg/g dry weight (DW) while ascorbic acid equivalent antioxidant capacity (AEAC) varied from 57.2 to 158.1 mg AEAC/100 g fresh weight (FW). Generally, lower vitamin E content or antioxidant capacity was observed in hulless or coloured genotypes. These results suggest that some genotypes are potential candidates for breeding of barley cultivars with high vitamin E content or antioxidant capacity at harvest, even after storage. Copyright © 2015 Elsevier Ltd. All rights reserved.

Topical Vitamin C and the Skin: Mechanisms of Action and Clinical Applications.

PubMed

Al-Niaimi, Firas; Chiang, Nicole Yi Zhen

2017-07-01

OBJECTIVE: This review article details the main mechanisms of action and clinical applications of topical vitamin C on the skin, including its antioxidative, photoprotective, antiaging, and antipigmentary effects. DESIGN: A PubMed search for the relevant articles on vitamin C and the skin was conducted using the following key words: "vitamin C," "ascorbic acid," "ascorbyl-6-palmitate,"and "magnesium ascorbyl phosphate." RESULTS: As one of the most powerful antioxidants in the skin, vitamin C has been shown to protect against photoaging, ultraviolet-induced immunosuppression, and photocarcinogenesis. It also has an antiaging effect by increasing collagen synthesis, stabilizing collagen fibers, and decreasing collagen degradation. It decreases melanin formation, thereby reducing pigmentation. Vitamin C is the primary replenisher of vitamin E and works synergistically with vitamin E in the protection against oxidative damage. CONCLUSION: Topical vitamin C has a wide range of clinical applications, from antiaging and antipigmentary to photoprotective. Currently, clinical studies on the efficacy of topical formulations of vitamin C remain limited, and the challenge lies in finding the most stable and permeable formulation in achieving the optimal results.

Intracellular ascorbate tightens the endothelial permeability barrier through Epac1 and the tubulin cytoskeleton

PubMed Central

Parker, William H.; Rhea, Elizabeth Meredith; Qu, Zhi-Chao; Hecker, Morgan R.

2016-01-01

Vitamin C, or ascorbic acid, both tightens the endothelial permeability barrier in basal cells and also prevents barrier leak induced by inflammatory agents. Barrier tightening by ascorbate in basal endothelial cells requires nitric oxide derived from activation of nitric oxide synthase. Although ascorbate did not affect cyclic AMP levels in our previous study, there remains a question of whether it might activate downstream cyclic AMP-dependent pathways. In this work, we found in both primary and immortalized cultured endothelial cells that ascorbate tightened the endothelial permeability barrier by ∼30%. In human umbilical vein endothelial cells, this occurred at what are likely physiologic intracellular ascorbate concentrations. In so doing, ascorbate decreased measures of oxidative stress and also flattened the cells to increase cell-to-cell contact. Inhibition of downstream cyclic AMP-dependent proteins via protein kinase A did not prevent ascorbate from tightening the endothelial permeability barrier, whereas inhibition of Epac1 did block the ascorbate effect. Although Epac1 was required, its mediator Rap1 was not activated. Furthermore, ascorbate acutely stabilized microtubules during depolymerization induced by colchicine and nocodazole. Over several days in culture, ascorbate also increased the amount of stable acetylated α-tubulin. Microtubule stabilization was further suggested by the finding that ascorbate increased the amount of Epac1 bound to α-tubulin. These results suggest that physiologic ascorbate concentrations tighten the endothelial permeability barrier in unstimulated cells by stabilizing microtubules in a manner downstream of cyclic AMP that might be due both to increasing nitric oxide availability and to scavenging of reactive oxygen or nitrogen species. PMID:27605450

Interactions and encapsulation of vitamins C, B3, and B6 with dendrimers in water.

PubMed

Boisselier, Elodie; Liang, Liyuan; Dalko-Csiba, Maria; Ruiz, Jaime; Astruc, Didier

2010-05-25

Titrations of commercial diaminobutane (DAB) and polyamidoamine (PAMAM) dendrimers by vitamins C (ascorbic acid, AA), B(3) (nicotinic acid), and B(6) (pyridoxine) were monitored by (1)H NMR spectroscopy using the chemical shifts of both dendrimer and vitamin protons and analyzed by comparison with the titration of propylamine. Quaternarizations of the terminal primary amino groups and intradendritic tertiary amino groups, which are nearly quantitative with vitamin C, were characterized by more or less sharp variations (Deltadelta) of the (1)H chemical shift (delta) at the equivalence points. The peripheral primary amino groups of the DAB dendrimers were quaternarized first, but not selectively, whereas a sharp chemical-shift variation was recorded for the inner methylene protons near the tertiary amines, thereby indicating encapsulation, when all the dendritic amines were quaternarized. With DAB-G5-64-NH(2), some excess acid is required to protonate the inner amino groups, presumably because of basicity decrease due to excess charge repulsion. On the other hand, this selectivity was not observed with PAMAM dendrimers. The special case of the titration of the dendrimers by vitamin B(6) indicates only dominant supramolecular hydrogen-bonding interactions and no quaternarization, with core amino groups being privileged, which indicates the strong tendency to encapsulate vitamins. With vitamin B(3), a carboxylic acid, titration of DAB-G3-16-NH(2) shows that only six peripheral amino groups are protonated on average, even with excess vitamin B(3), because protonation is all the more difficult due to increased charge repulsion, as positive charges accumulate around the dendrimer. Inner amino groups interact with this vitamin, however, thus indicating encapsulation presumably with supramolecular hydrogen bonding without much charge transfer.

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.

Ultrastructural aspects of autoschizis: a new cancer cell death induced by the synergistic action of ascorbate/menadione on human bladder carcinoma cells.

PubMed

Gilloteaux, J; Jamison, J M; Arnold, D; Taper, H S; Summers, J L

2001-01-01

Scanning and transmission electron microscopy were employed to further characterize the cytotoxic effects of a ascorbic acid/menadione (or vitamin C/vitamin K3) combination on a human bladder carcinoma T24 cell line. Following 1-h treatment T24 cells display membrane and mitochondrial defects as well as excision of cytoplasmic fragments that contain no organelles. These continuous self-excisions reduce the cell size. Concomitant, nuclear changes, chromatin disassembly, nucleolar condensation and fragmentation, and decreased nuclear volume lead to cell death via a process similar to karyorrhexis and karyolysis. Because this cell death is achieved through a progressive loss of cytoplasm due to self-morsellation, the authors named this mode of cell death autoschizis (from the Greek autos, self, and schizein, to split, as defined in Scanning. 1998; 20: 564-575). This morphological characterization of autoschizic cell death confirms and extends the authors previous reports and demonstrates that this cell death is distinct from apoptosis.

Vitamins in Heart Failure: Friend or Enemy?

PubMed

Georgiopoulos, George; Chrysohoou, Christina; Vogiatzi, Georgia; Magkas, Nikolaos; Bournelis, Ippokratis; Bampali, Sofia; Gruson, Damien; Tousoulis, Dimitris

2017-01-01

The failing heart is characterized by a depleted metabolic energy reserve and the upregulation of several molecular mechanisms leading to cardiac hypertrophy, inflammation, fibrosis, angiogenesis, and apoptosis. Dietary or non-dietary supplementation of vitamins could potentially benefit energy balance. The objective of the present study was to evaluate all available information on vitamins supplementation in patients with chronic HF for possible beneficial effect on metabolic, inotropic, chronotropic and hemodynamic indices. We searched MEDLINE via Pubmed by using the following terms: "chronic heart failure" OR "cardiomyopathy" AND "vitamins", "vitamin A", "B complex vitamins", "vitamin C", "ascorbic acid", "vitamin D", "retinol", "vitamin E", "thiamine", "riboflavin", "niacin", "pyridoxine", "cobalamin", "folate", "pantothenic acid", "biotin", "tocopherol" and combinations of them. Data regarding supplementation of micronutrients in HF for most vitamins were sparse, and the inference about cardiovascular outcomes was obscured by the heterogeneity of studies, high inherent morbidity, and mortality of this group of high-risk patients, limited sample sizes in certain studies, unclear design and lack of head to head comparisons. Most vitamins in human trials failed to offer survival, or robust beneficial effect. Mostly indirect favorable evidence is derived from patients with deficiencies of certain micronutrients rather than their ad hoc supplementation. While vitamins and micronutrients are promising compounds for optimizing myocardial metabolism and homeostasis in HF, additional randomized clinical trials of larger scale are warranted to demonstrate the benefits of their supplementation in this high risk group of patients. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Ascorbate modulates antibacterial mechanisms in experimental pneumococcal pneumonia.

PubMed

Esposito, A L

1986-04-01

To evaluate the influence of vitamin C on pulmonary antibacterial mechanisms, normal CD-1 mice were administered sodium ascorbate (200 mg/kg/24 h) and challenged intratracheally with type 3 Streptococcus pneumoniae. Survival rates were similar in ascorbate-treated and control animals. When infected with a high inoculum (1 X 10(6) cfu), animals given vitamin C demonstrated a significant enhancement in their capacity to clear viable pneumococci from the lungs at 24 h after challenge; the augmented pulmonary clearance was associated with an increased influx of granulocytes at 6 and 24 h. After infection with a lower inoculum (1 X 10(5) cfu), animals treated with the vitamin exhibited a significant advantage in pulmonary clearance and granulocyte recruitment but at 6 h only. After a very low inoculum challenge (1 X 10(4) cfu), the clearance of viable pneumococci was retarded in ascorbate-treated mice. In vitro, the pneumococcidal capacity of resident alveolar macrophages from animals given vitamin C was significantly reduced, but the ability of these cells to generate leukocyte chemoattractant activity after stimulation with the calcium ionophore A23187 remained unaltered. We conclude that in the mouse, large doses of vitamin C alter pulmonary defense mechanisms against S. pneumoniae; however, these changes do not appear to convey a substantial advantage to the host.

Vitamins and cancer prevention: issues and dilemmas.

PubMed

Young, V R; Newberne, P M

1981-03-01

Vitamins are a class of organic compounds that are components of an adequate diet. They or their derivatives function as coenzymes, cellular antioxidants, and/or regulators of gene expression. Fourteen vitamins are recognized in human nutrition (Vitamins A, D, E, K, B1, B2, B6, B12, C, niacin, folacin, pantothenic acid, biotin, choline), with deficiencies or excesses in intake leading to changes in protein, nucleic acid, carbohydrates, fat and/or mineral metabolism. Thus, the integrity of physiological systems, including those associated with detoxification, cellular repair, immune processes, and neural and endocrine function, depends upon the nutritional and vitamin status of the host. For these reasons, it may be anticipated that the adequacy of the vitamin supply to cells and tissues would affect the development, progress, and outcome of cancers. In this review, the definition and functions of and requirements and recommended allowance for vitamins are discussed briefly before exploring the evidence, largely from studies in experimental animals, that indicates the nature of the link between vitamins and cancer. Although evidence based on studies in animal systems reveals that vitamin intake and status can modulate the outcome of experimental carcinogenesis, the findings are often conflicting and difficult to interpret. Furthermore, it is not yet possible to develop a suitable prediction of the role of the individual vitamins in tumor development. The significance of these observations for human nutrition and cancer prevention, particularly in reference to ascorbic acid (vitamin C), vitamin E, and B-complex vitamins is considered. Vitamin A and retinoid compounds are discussed elsewhere in the symposium. The many popular misconceptions and unsound advice concerning vitamins and health, including "fake" vitamins-pangamic acid ("vitamin B15") and laetrile ("vitamin B17")-are also discussed. On the basis of current evidence, it would be inappropriate to recommend either substantial changes in habitual vitamin intakes, as provided by an adequate, well-balanced diet, or promotion of megavitamin intakes, as a means of reducing risk from cancers in the human population. However, a prudent approach toward diet and food habits, as a means of better optimizing the health consequences of our complex lifestyle is to be recommended.

Toxic effects of lambda-cyhalothrin, a synthetic pyrethroid pesticide, on the rat kidney: Involvement of oxidative stress and protective role of ascorbic acid.

PubMed

Fetoui, Hamadi; Makni, Mohamed; Garoui, El Mouldi; Zeghal, Najiba

2010-11-01

Lambda-cyhalothrin is a synthetic pyrethroid insecticide used worldwide in agriculture, home pest control, protection of foodstuff and disease vector control. The objective of this study was to investigate the propensity of lambda-cyhalothrin (LTC) to induce oxidative stress, changes in biochemical parameters and enzyme activities in the kidney of male rats and its possible attenuation by Vitamin C (vit C). Renal function, histopathology, tissue malondialdehyde (MDA), protein carbonyl (PCO) levels, antioxidant enzyme activities and reduced glutathione (GSH) levels were evaluated. Exposure of rats to lambda-cyhalothrin, during 3 weeks, caused a significant increase in kidney MDA and protein carbonyl levels (p<0.01) as compared to controls. Co-administration of vitamin C was effective in reducing MDA and PCO levels. The kidney of LTC-treated rats exhibited severe vacuolations, cells infiltration and widened tubular lumen. The activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione-S-transferase (GST) were significantly decreased due to lambda-cyhalothrin exposure. Co-administration of vitamin C ameliorated the increase in enzymatic activities of aminotransferases (AST and ALT), lactate dehydrogenase (LDH), creatinine and urea levels and improved the antioxidant status. These data indicated the protective role of ascorbic acid against lambda-cyhalothrin-induced nephrotoxicity and suggested a significant contribution of its antioxidant property to these beneficial effects. Copyright © 2009 Elsevier GmbH. All rights reserved.

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.

Evaluation of the antioxidant activity of root extract of pepper fruit (Dennetia tripetala), and it's potential for the inhibition of lipid peroxidation.

PubMed

Okolie, Ngozi Paulinus; Falodun, Abiodun; Davids, Oluseyi

2014-01-01

The antioxidant properties of ethanolic root extract of pepper fruit (Donnetia tripetala), and its effect on lipid peroxidation of some fresh beef tissues during frozen storage were investigated. The antioxidant parameters were assessed using standard methods, while malondialdehyde levels of different fresh beef tissue sections treated with the extract prior to freezing, were estimated in a colorimetric reaction with thiobarbituric acid. The H2O2-scavenging ability of the extract was similar to that of ascorbic acid, with a maximum scavenging power of 55.61 ±4.98%, and an IC50 value of 86µg/ml. The extract exhibited a concentration-dependent ferric ion-reducing power, although this was significantly lower relative to that of the ascorbic acid (p < 0.05). The total phenolic content was 212.5 ± 0.002 mg/g, while the nitric oxide-scavenging ability was 64.33 ± 0.2% after 150 min. The capacity of the extract to inhibit lipid peroxidation in frozen heart muscle slices was significantly higher than that of vitamin C (p < 0 .05), but comparable to vitamins C and E in frozen testes and kidney slices. These results suggest that the root extract of D. tripetala is rich in antioxidants which can be applied to meat preservation during refrigerated storage.

Vitamine--vitamin. The early years of discovery.

PubMed

Rosenfeld, L

1997-04-01

In 1905, Cornelius Adrianus Pekelharing found that animals fed purified proteins, carbohydrates, fats, inorganic salts, and water would thrive only if small amounts of milk were added to the diet. He concluded that the milk contained some unrecognized substance that in very small quantities was necessary for normal growth and maintenance. In 1911, Casimir Funk isolated a concentrate from rice polishings that cured polyneuritis in pigeons. He named the concentrate "vitamine" because it appeared to be vital to life and because it was probably an amine. Although the concentrate and other "accessory food substances" were not amines, the name stuck, but the final "e" was dropped. In 1913 two groups discovered a "fat-soluble" accessory food substance. Initially believed to be a single vitamin, two separate factors were involved. One, effective against xerophthalmia, was named vitamin A; the other, effective against rickets, was named vitamin D. The factor that prevented scurvy was isolated in 1928. Known as "water-soluble C," it was renamed ascorbic acid.

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.

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

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

Alternative pathways of dehydroascorbic acid degradation in vitro and in plant cell cultures: novel insights into vitamin C catabolism.

PubMed

Parsons, Harriet T; Yasmin, Tayyaba; Fry, Stephen C

2011-12-15

L-Ascorbate catabolism involves reversible oxidation to DHA (dehydroascorbic acid), then irreversible oxidation or hydrolysis. The precursor-product relationships and the identity of several major DHA breakdown products remained unclear. In the presence of added H2O2, DHA underwent little hydrolysis to DKG (2,3-dioxo-L-gulonate). Instead, it yielded OxT (oxalyl L-threonate), cOxT (cyclic oxalyl L-threonate) and free oxalate (~6:1:1), essentially simultaneously, suggesting that all three product classes independently arose from one reactive intermediate, proposed to be cyclic-2,3-O-oxalyl-L-threonolactone. Only with plant apoplastic esterases present were the esters significant precursors of free oxalate. Without added H2O2, DHA was slowly hydrolysed to DKG. Downstream of DKG was a singly ionized dicarboxy compound (suggested to be 2-carboxy-L-xylonolactone plus 2-carboxy-L-lyxonolactone), which reversibly de-lactonized to a dianionic carboxypentonate. Formation of these lactones and acid was minimized by the presence of residual unreacted ascorbate. In vivo, the putative 2-carboxy-L-pentonolactones were relatively stable. We propose that DHA is a branch-point in ascorbate catabolism, being either oxidized to oxalate and its esters or hydrolysed to DKG and downstream carboxypentonates. The oxidation/hydrolysis ratio is governed by reactive oxygen species status. In vivo, oxalyl esters are enzymatically hydrolysed, but the carboxypentonates are stable. The biological roles of these ascorbate metabolites invite future exploration.

Effects of excess pantothenic acid administration on the other water-soluble vitamin metabolisms in rats.

PubMed

Shibata, Katsumi; Takahashi, Chisato; Fukuwatari, Tsutomu; Sasaki, Ryuzo

2005-12-01

To acquire the data concerning the tolerable upper intake level which prevents health problems from an excessive intake of pantothenic acid, an animal experiment was done. Rats of the Wistar strain (male, 3 wk old) were fed on a diet which contains 0%, 0.0016% (control group), 1%, or 3% calcium pantothenate for 29 d. The amount of weight increase, the food intake, and the organ weights were measured, as well as the pantothenic acid contents in urine, the liver and blood. Moreover, to learn the influence of excessive pantothenic acid on other water-soluble vitamin metabolism, thiamin, riboflavin, a vitamin B6 catabolite, the niacin catabolites, and ascorbic acid in urine were measured. As for the 3% addition group, enlargement of the testis, diarrhea, and hair damage were observed, and the amount of weight increase and the food intake were less than those of the control group. However, abnormality was not seen in the 1% addition group. The amount of pantothenic acid in urine, the liver, and blood showed a high correlation with intake level of pantothenic acid. It was only for 4-pyridoxic acid, a vitamin B6 catabolite, in urine that a remarkable difference was observed against the control group. Moreover, the (2-Py+4-Py)/MNA excretion ratio for these metabolites of the nicotinamide also indicated a low value in the 3% pantothenic acid group. As for the calcium pantothenate, it was found that the 3% level in the diet was the lowest-observed-adverse-effect-level (LOAEL) and the 1% level was the no-observed-adverse-effect-level (NOAEL).

[Anatomical Vitamin C-Research during National Socialism and the Post-war Period: Max Clara's Human Experiments at the Munich Anatomical Institute].

PubMed

Schûtz, Mathias; Schochow, Maximilian; Waschke, Jens; Marckmann, Georg; Steger, Florian

2014-01-01

In autumn of 1942, Max Clara (1899-1966) became chairman of the anatomical institute Munich. There, he intensified his research concerning the proof of vitamin C with the bodies of executed prisoners which were delivered by the Munich-Stadelheim prison. This research on human organs was pursued by applying ascorbic acid (Cebion) to prisoners before their execution. The paper investigates this intensified and radicalized anatomical research through human experiments, which Max Clara conducted in Munich and published from Istanbul during the postwar years, as well as its scientific references from the Nazi period.

Potentiometric assessment of iron release during ferritin reduction by exogenous agents.

PubMed

Vladimirova, Lilia S; Kochev, Valery K

2010-09-01

This work studied the possibilities for quantitative determination of iron mobilization in connection with ferritin reduction by ascorbic acid (vitamin C) and sodium dithionite in vitro. The iron storage protein was incubated with an excess of reductant in aerobic conditions in the absence of complexing agents in the medium. The release of Fe(2+) was let to go to completion, and the overall content of Fe(2+) in the solution was evaluated with the aid of potentiometric titration using Ce(4+) as an oxidizing titrant. Results suggest a moderate iron efflux under the influence of the chosen reducing agents. Although such a reduction of the protein mineral core by dihydroxyfumarate contributes greatly to the iron mobilization, ferritin behavior with vitamin C and dithionite seems to be different. Although redox properties of dihydroxyfumarate are determined by hydroxyl groups similar to those of ascorbic acid, the two compounds differ significantly in structure, and this could be the basis for an explanation of the specificities in their interaction with ferritin. As revealed by the study, potentiometric titration promises to be a reliable tool for evaluation of the amount of Fe(2+) present in the solution as a result of the reduction of the ferritin's mineral core. 2010 Elsevier Inc. All rights reserved.

Topical Vitamin C and the Skin: Mechanisms of Action and Clinical Applications

PubMed Central

Al-Niaimi, Firas

2017-01-01

OBJECTIVE: This review article details the main mechanisms of action and clinical applications of topical vitamin C on the skin, including its antioxidative, photoprotective, antiaging, and antipigmentary effects. DESIGN: A PubMed search for the relevant articles on vitamin C and the skin was conducted using the following key words: “vitamin C,” “ascorbic acid,” “ascorbyl-6-palmitate,”and “magnesium ascorbyl phosphate.” RESULTS: As one of the most powerful antioxidants in the skin, vitamin C has been shown to protect against photoaging, ultraviolet-induced immunosuppression, and photocarcinogenesis. It also has an antiaging effect by increasing collagen synthesis, stabilizing collagen fibers, and decreasing collagen degradation. It decreases melanin formation, thereby reducing pigmentation. Vitamin C is the primary replenisher of vitamin E and works synergistically with vitamin E in the protection against oxidative damage. CONCLUSION: Topical vitamin C has a wide range of clinical applications, from antiaging and antipigmentary to photoprotective. Currently, clinical studies on the efficacy of topical formulations of vitamin C remain limited, and the challenge lies in finding the most stable and permeable formulation in achieving the optimal results. PMID:29104718

A complex of antioxidant vitamins effectively inhibits free-radical oxidation of LDL phospholipids in blood plasma and membrane structures of the liver and myocardium.

PubMed

Konovalova, G G; Lisina, M O; Tikhaze, A K; Lankin, V Z

2003-02-01

Antioxidant effect of a complex preparation including antioxidant vitamins C, E, provitamin A and selenium was studied on the model of Cu(2+)-initiated free-radical oxidation of LDL isolated from human blood plasma. The antioxidant effect of combined administration of alpha-tocopherol+ascorbic acid and alpha-tocopherol+beta-carotene is far more pronounced that the antioxidant effect of individual components of these cocktails. Moreover, in the model system the combined action of all antioxidant components completely inhibited free-radical oxidation of LDL. A 30-day course of peroral administration of antioxidant vitamin cocktail and selenium to rats pronouncedly enhanced the antioxidant potential of liver and completely suppressed free-radical processes in the myocardium. It is suggested that preparations containing antioxidant vitamins and selenium can be perspective for prevention and complex therapy of atherosclerosis.

Infantile scurvy: an old diagnosis revisited with a modern dietary twist.

PubMed

Burk, Cynthia J; Molodow, Rona

2007-01-01

Ascorbic acid (vitamin C) is necessary for the formation of collagen, reducing free radicals, and aiding in iron absorption. Scurvy, a disease of dietary ascorbic acid deficiency, is uncommon today. Indeed, implementation of dietary recommendations largely eradicated infantile scurvy in the US in the early 1900s. We present a case of an otherwise healthy 2-year-old Caucasian girl who presented with refusal to walk secondary to pain in her lower extremities, generalized irritability, sleep disturbance, and malaise. The girl's parents described feeding the patient an organic diet recommended by the Church of Scientology that included a boiled mixture of organic whole milk, barley, and corn syrup devoid of fruits and vegetables. Physical examination revealed pale, bloated skin with edematous, violaceous gums and loosening of a few of her teeth. Dermatologic findings included xerosis, multiple scattered ecchymoses of the extremities, and perifollicular hemorrhage. Laboratory and radiographic evaluation confirmed the diagnosis of scurvy. The patient showed dramatic improvement after only 3 days of treatment with oral ascorbic acid and significant dietary modification. In this case report, we revisit the old diagnosis of scurvy with a modern dietary twist secondary to religious practices. This case highlights the importance of taking a detailed dietary history when evaluating diseases involving the skin.

The Transcription Factor ABI4 Is Required for the Ascorbic Acid–Dependent Regulation of Growth and Regulation of Jasmonate-Dependent Defense Signaling Pathways in Arabidopsis[C][W

PubMed Central

Kerchev, Pavel I.; Pellny, Till K.; Vivancos, Pedro Diaz; Kiddle, Guy; Hedden, Peter; Driscoll, Simon; Vanacker, Hélène; Verrier, Paul; Hancock, Robert D.; Foyer, Christine H.

2011-01-01

Cellular redox homeostasis is a hub for signal integration. Interactions between redox metabolism and the ABSCISIC ACID-INSENSITIVE-4 (ABI4) transcription factor were characterized in the Arabidopsis thaliana vitamin c defective1 (vtc1) and vtc2 mutants, which are defective in ascorbic acid synthesis and show a slow growth phenotype together with enhanced abscisic acid (ABA) levels relative to the wild type (Columbia-0). The 75% decrease in the leaf ascorbate pool in the vtc2 mutants was not sufficient to adversely affect GA metabolism. The transcriptome signatures of the abi4, vtc1, and vtc2 mutants showed significant overlap, with a large number of transcription factors or signaling components similarly repressed or induced. Moreover, lincomycin-dependent changes in LIGHT HARVESTING CHLOROPHYLL A/B BINDING PROTEIN 1.1 expression were comparable in these mutants, suggesting overlapping participation in chloroplast to nucleus signaling. The slow growth phenotype of vtc2 was absent in the abi4 vtc2 double mutant, as was the sugar-insensitive phenotype of the abi4 mutant. Octadecanoid derivative-responsive AP2/ERF-domain transcription factor 47 (ORA47) and AP3 (an ABI5 binding factor) transcripts were enhanced in vtc2 but repressed in abi4 vtc2, suggesting that ABI4 and ascorbate modulate growth and defense gene expression through jasmonate signaling. We conclude that low ascorbate triggers ABA- and jasmonate-dependent signaling pathways that together regulate growth through ABI4. Moreover, cellular redox homeostasis exerts a strong influence on sugar-dependent growth regulation. PMID:21926335

Transfer of Vitamins E and A from yolk to embryo during development of the king penguin (Aptenodytes patagonicus).

PubMed

Surai, P F; Speake, B K; Decrock, F; Groscolas, R

2001-01-01

Since the yolk lipids of the king penguin (Aptenodytes patagonicus) are rich in n-3 fatty acids, which are potentially susceptible to peroxidative damage, the yolk contents and yolk-to-embryo transfer of antioxidants and lipid-soluble vitamins were investigated under conditions of natural incubation in the wild. The concentration of vitamin E in the unincubated egg was 155 microg/g wet yolk, of which 88% was alpha-tocopherol and the rest was gamma-tocopherol. Vitamin A (2.9 microg/g) was present in the yolk entirely as retinol; no retinyl esters were detected. Throughout the latter half of the incubation period, vitamins E and A were taken up from the yolk into the yolk sac membrane (YSM) and later accumulated in the liver, with vitamin A being transferred in advance of vitamin E. In the YSM, vitamin A was present almost entirely as retinyl ester, indicating that the free retinol of the yolk is rapidly esterified following uptake. Retinyl esters were also the predominant form in the liver. The retinyl esters of the liver and YSM displayed different fatty acid profiles. At hatching, the brain contained relatively little vitamin E (4.7 microg/g) compared to the much higher concentration in the liver (482.9 microg/g) at this stage. Ascorbic acid was not detected in the yolk but was present at a high concentration in the brain at day 27 (404.6 microg/g), decreasing to less than half this value by the time of hatching. This report is the first to delineate the yolk-to-embryo transfer of lipid-soluble vitamins for a free-living avian species. The yolk fatty acids of the king penguin provide an extreme example of potential oxidative susceptibility, forming a basis for comparative studies on embryonic antioxidant requirements among species of birds whose yolk lipids differ in their degree of unsaturation.

Integrated analysis of multiomic data reveals the role of the antioxidant network in the quality of sea buckthorn berry.

PubMed

He, Caiyun; Zhang, Guoyun; Zhang, Jianguo; Zeng, Yanfei; Liu, Juanjuan

2017-05-01

Berries of sea buckthorn, known as the "king of vitamin C," are abundant in antioxidants, have attractive colors, and are an excellent material with which to study the relationships between berry color, antioxidants, and berry quality. No study has yet determined the molecular basis of the relationship between sea buckhorn berries and their color and antioxidant levels. By using RNA-seq, LC-MS/MS, and LC/GC-MS technology and selecting red (darkest colored) and yellow (lightest colored) sea buckthorn berries at different development stages, this study showed that the red and yellow berry resulted from a higher ratio of lycopene to β-carotene and of β-carotene to lycopene content, respectively. The uronic acid pathway-a known animal pathway-in ascorbic acid synthesis was found in sea buckthorn berries, and the higher expression of UDP-glucuronosyltransferase in red berries was consistent with the higher content of ascorbic acid. In summary, multiomic data showed that the color of sea buckthorn berries is mainly determined by β-carotene and lycopene; red sea buckthorn berries were richer than yellow berries in antioxidants, such as carotenoids, flavonoids, and ascorbic acid; and the animal pathway might be operating in sea buckthorn.-He, C., Zhang, G., Zhang, J., Zeng, Y., Liu, J. Integrated analysis of multiomic data reveals the role of the antioxidant network in the quality of sea buckthorn berry. © FASEB.

Erythrocyte concentrations of B1, B2, B6 but not plasma C and E are reliable indicators of nutrition status in the presence of systemic inflammation.

PubMed

Ghashut, Rawia A; McMillan, Donald C; Kinsella, John; Talwar, Dinesh

2017-02-01

There is increasing evidence that the plasma concentration of vitamin D, carotenoids, zinc and selenium are associated with the magnitude of the systemic inflammatory response. In order to examine whether other vitamins may be affected and whether red cell concentrations are less affected by systemic inflammation the aim of the present study was to examine the effect of the systemic inflammatory response on red cell measurements of vitamins B1, B2 and B6, and plasma concentration of vitamin C and E in a large cohort of patients referred for a nutritional screen. Patients referred for nutritional assessment of B1 (n = 551), B2 (n = 251), B6 (n = 313), ascorbic acid (n = 494) and α-tocopherol (n = 395) concentrations. These vitamins were measured using routine laboratory methods. The median concentrations of vitamin B1 grouped according to C-reactive protein concentrations ≤10, 11-80 and >80 mg/L were 543, 664 and 766 ng/g Hb respectively (p < 0.001, 41% higher). The median concentration of vitamin B1 grouped according to albumin concentrations ≥35, 25-34 and <25 g/l were 547, 664 and 701 ng/g Hb respectively (p < 0.001, 28% higher). The median concentrations of red cell vitamin B2 grouped according to CRP concentrations ≤10, 11-80 and >80 mg/L were 2.2, 2.3 and 2.4 nmol/g Hb respectively (p < 0.001, 9% higher). The median red cell concentrations of vitamin B2 grouped according to albumin concentrations ≥35, 25-34 and <25 g/l were 2.1, 2.4 and 2.3 nmol/g Hb respectively (p < 0.001, 14% higher). The median concentrations of red cell vitamin B6 grouped according to CRP concentrations ≤10, 11-80 and >80 mg/L were 534, 548 and 767 pmol/g Hb respectively (p < 0.001, 44% higher). The median red cell concentrations of vitamin B6 grouped according to albumin concentrations ≥35, 25-34 and <25 g/l were 462, 644 and 840 pmol/g Hb respectively (p < 0.001, 82% higher). In contrast, the median plasma concentrations of ascorbic acid grouped according to CRP concentrations ≤10, 11-80 and >80 mg/L were 25.0, 15.0 and 6.0 μmol/l respectively (78% lower, p < 0.001). The median plasma concentrations of ascorbic acid grouped according to albumin concentrations ≥35, 25-34 and <25 g/l were 32.0, 13.0 and 5.0 μmol/l respectively (84% lower, p < 0.001). The median α-tocopherol/cholesterol grouped according to CRP concentrations ≤10, 11-80 and >80 mg/L were 5.9, 4.6 and 2.1 μmol/l respectively (64% lower, p < 0.001). The median α-tocopherol/cholesterol grouped according to albumin concentrations ≥35, 25-34 and <25 g/l were 6.0, 5.5 and 2.1 μmol/l respectively (65% lower, p < 0.001). Red cell concentrations of vitamins B1, B2 and B6 were not lower with an increasing systemic inflammatory response. In contrast, plasma concentrations of vitamin C and E were lower. Therefore, compared with plasma concentration, red cell concentrations of B1, B2 and B6 are likely to be more reliable measures of status in the presence of a systemic inflammatory response. Copyright © 2016 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.

Deficiency of vitamin D and vitamin C in the pathogenesis of bronchial asthma.

PubMed

Ginter, E; Simko, V

2016-01-01

Epidemiology of bronchial asthma (BA) indicates a marked paradox: rapid rise in the prevalence.Simultaneous decline in mortality is mostly related to improvement in the diagnosis and therapy. In many economically developed countries the BA affects more than 10 per cent of the population, while mortality related to this respiratory disorder is below 1/100,000. Factors favorably influencing mortality of BA include new more effective medications, decline in smoking and also improved nutrition, based on awareness of protective role of vitamins. Vitamin D deficiency has a number of biological effects that are potentially instrumental in the pathogenesis and severity of BA. Increased number of randomized, controlled, interventional studies is showing positive effects of vitamin D supplementation in pediatric and in adult BA. Oxidative stress is potentially an important pathogenic factor in the progression of BA. Vitamin C (ascorbic acid) belongs to the most effective nutritional antioxidants. By counteracting oxidants, reducing generation of reactive oxygen species, vitamin C may inhibit external attacks in the respiratory tract, thus modulating the development of BA (Fig. 2, Ref. 15).

Cytotoxicity and mutagenicity of fluoxetine hydrochloride (Prozac), with or without vitamins A and C, in plant and animal model systems.

PubMed

Düsman, E; Almeida, I V; Mariucci, R G; Mantovani, M S; Vicentini, V E P

2014-01-28

Fluoxetine, commonly known as Prozac, is the first representative of the so-called new generation of antidepressants that promise efficacy, with few side effects, against deep depression, nervous bulimia, and anxiety. As there is a growing number of people suffering from anxiety and depression; consequently, the use of fluoxetine is also increasing. Verifying absence of drug effects such as cytotoxicity or mutagenicity is of great importance. Certain vitamins, such as vitamin A (retinol, retinoids) and vitamin C (ascorbic acid) protect and are extremely active against mutagens. We evaluated the cytotoxic and mutagenic activity of fluoxetine, with and without concomitant administration of vitamin A or C, in Allium cepa meristem cells and Wistar rat bone marrow cells. The A. cepa meristem cells showed fluoxetine cytotoxicity; concomitant treatment with vitamin A or C proved non-protective. Treatment of Wistar rats with fluoxetine intraperitoneally or via gavage did not affect cell division or cause clastogenic effects. Vitamin A and C did not affect the cytotoxicity or mutagenicity of fluoxetine in the rat cells.

Effect of omega-3 and ascorbic acid on inflammation markers in depressed shift workers in Shahid Tondgoyan Oil Refinery, Iran: a randomized double-blind placebo-controlled study

PubMed Central

Khajehnasiri, Farahnaz; Mortazavi, Seyed Bagher; Allameh, Abdolamir; Akhondzadeh, Shahin

2013-01-01

The present study aimed to assess the effect of supplementation of omega-3 and/or vitamin C on serum interleukin-6 and high sensitivity C-reactive protein concentration and depression scores among shift workers in Shahid Tondgoyan oil refinery. The study design was randomized, double-blind, placebo-controlled, parallel trial. Totally 136 shift workers with a depression score ≥10 in 21-item Beck Depression Rating Scale were randomly assigned to receive omega-3 (180 mg eicosapentaenoate acid and 120 mg docosahexaenoic acid) or/and vitamin C 250 mg or placebo twice daily (with the same taste and shape as omega-3 and vitamin C) for 60 days in four groups. Depression score, interleukin-6 and high sensitivity C-reactive protein were measured at baseline and after 60 days. This study showed that supplementation of omega-3 plus vitamin C is associated with a decrease in depression score (p<0.05). Supplementation of omega-3 without vitamin C, is associated with a reduction in depression score (p<0.0001) and high sensitivity C-reactive protein concentration (p<0.01). Therefore omega-3 supplementation showed a better effect on reducing depression score and high sensitivity C-reactive protein, but supplementation of vitamin C along with omega-3 did not have significant effect on change in C-reactive protein level compared to omega-3 alone. (Registration number: IRCT201202189056N1) PMID:23874068

Inhibiting the photosensitized oxidation of anthracene and tryptophan by means of natural antioxidants

NASA Astrophysics Data System (ADS)

Aksenova, N. A.; Vyzhlova, E. N.; Malinovskaya, V. V.; Parfenov, V. V.; Solov'eva, A. B.; Timashev, P. S.

2013-08-01

It is shown that model reactions of photosensitized oxidation of anthracene and tryptophan can be used for evaluation and comparison of antioxidant activity of various classes of compounds. Inhibition of the oxidation of substrates in the presence of the familiar antioxidants tocopherol (vitamin E), ascorbic acid (vitamin C), and mixtures of these vitamins with methionine, and in the presence of reputed antioxidants dihydroquercetin and taurine, are considered. It is concluded that all of the above compounds except for taurine have antioxidant properties; i.e., they reduce the rate constants of the photosensitized oxidation of anthracene and tryptophan. It is found that the inhibition of oxidation is associated with the interaction between antioxidants and singlet oxygen. Analysis of the kinetic dependences of the photosensitized oxidation of substrates in the presence of antioxidants reveals that a mixture of vitamins inhibits the process most efficiently, and inhibition occurs at the initial stages due to more active interaction between singlet oxygen and vitamin C

[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 deterioration of vitamin E status at enriched with PUFA vitamin-deficient diet requires the additional intake of this vitamin for maintaining of vitamin E sufficiency.

Influence of stage of lactation and year season on composition of mares' colostrum and milk and method and time of storage on vitamin C content in mares' milk.

PubMed

Markiewicz-Kęszycka, Maria; Czyżak-Runowska, Grażyna; Wójtowski, Jacek; Jóźwik, Artur; Pankiewicz, Radosław; Łęska, Bogusława; Krzyżewski, Józef; Strzałkowska, Nina; Marchewka, Joanna; Bagnicka, Emilia

2015-08-30

Mares' milk is becoming increasingly popular in Western Europe. This study was thus aimed at investigating the impact of stage of lactation and season on chemical composition, somatic cell count and some physicochemical parameters of mares' colostrum and milk, and at developing a method for the determination of vitamin C (ascorbic acid) in mares' milk and to determine its content in fresh and stored milk. The analysis conducted showed an effect of the stage of lactation on contents of selected chemical components and physicochemical parameters of mares' milk. In successive lactation periods levels of fat, cholesterol, energy value, citric acid and titratable acidity decreased, whereas levels of lactose and vitamin C, as well as the freezing point, increased. Analysis showed that milk produced in autumn (September, October, November) had a higher freezing point and lower concentrations of total solids, protein, fat, cholesterol, citric acid and energy value in comparison to milk produced in summer (June, July, August). Mares' milk was characterised by low somatic cell count throughout lactation. In terms of vitamin C stability the most advantageous method of milk storage was 6-month storage of lyophilised milk. In general, the results confirmed that mares' milk is a raw material with a unique chemical composition different from that produced by other farm animals. © 2014 Society of Chemical Industry.

Iron Bioavailability and Provitamin A from Sweet Potato- and Cereal-Based Complementary Foods

PubMed Central

Christides, Tatiana; Amagloh, Francis Kweku; Coad, Jane

2015-01-01

Iron and vitamin A deficiencies in childhood are public health problems in the developing world. Introduction of cereal-based complementary foods, that are often poor sources of both vitamin A and bioavailable iron, increases the risk of deficiency in young children. Alternative foods with higher levels of vitamin A and bioavailable iron could help alleviate these micronutrient deficiencies. The objective of this study was to compare iron bioavailability of β-carotene-rich sweet potato-based complementary foods (orange-flesh based sweet potato (OFSP) ComFa and cream-flesh sweet potato based (CFSP) ComFa with a household cereal-based complementary food (Weanimix) and a commercial cereal (Cerelac®), using the in vitro digestion/Caco-2 cell model. Iron bioavailability relative to total iron, concentrations of iron-uptake inhibitors (fibre, phytates, and polyphenols), and enhancers (ascorbic acid, ß-carotene and fructose) was also evaluated. All foods contained similar amounts of iron, but bioavailability varied: Cerelac® had the highest, followed by OFSP ComFa and Weanimix, which had equivalent bioavailable iron; CFSP ComFa had the lowest bioavailability. The high iron bioavailability from Cerelac® was associated with the highest levels of ascorbic acid, and the lowest levels of inhibitors; polyphenols appeared to limit sweet potato-based food iron bioavailability. Taken together, the results do not support that CFSP- and OFSP ComFa are better sources of bioavailable iron compared with non-commercial/household cereal-based weaning foods; however, they may be a good source of provitamin A in the form of β-carotene. PMID:28231217

Determination of water-soluble vitamins in infant milk and dietary supplement using a liquid chromatography on-line coupled to a corona-charged aerosol detector.

PubMed

Márquez-Sillero, Isabel; Cárdenas, Soledad; Valcárcel, Miguel

2013-10-25

A simple and rapid method for the simultaneous determination of seven water-soluble vitamins (thiamine, folic acid, nicotinic acid, ascorbic acid, pantothenic acid, pyridoxine and biotin) was developed by high performance liquid chromatographic separation and corona-charged aerosol detection. The water-soluble vitamins were separated on a Lichrosorb RP-C18 column under isocratic conditions with a mobile phase consisting of 0.05 M ammonium acetate:methanol 90:10 (v/v) at the flow rate 0.5 mL min(-1). The vitamins were extracted from the infant milk (liquid and powder format) using a precipitation step with 2.5 M acetic acid remaining the analyte in the supernatant. As far as dietary supplements are concerned, only a dilution with distilled water was required. The detection limits ranged from 0.17 to 0.62 mg L(-1) for dietary supplements and 1.7 to 6.5 mg L(-1) for milk samples. The precision of the method was evaluated in terms of relative standard deviation (%, RSD) under repeatability and reproducibility conditions, being the average values for each parameter 2.6 and 2.7 for dietary supplements and 4.3 and 4.6 for milk samples. The optimized method was applied to different infant milk samples and dietary supplements. The results of the analysis were in good agreement with the declared values. Copyright © 2013 Elsevier B.V. All rights reserved.

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.

The coexistence of other micronutrient deficiencies in anaemic adolescent schoolgirls in rural Bangladesh.

PubMed

Ahmed, F; Khan, M R; Banu, C P; Qazi, M R; Akhtaruzzaman, M

2008-03-01

To investigate the prevalence of selected micronutrient deficiencies amongst anaemic adolescent schoolgirls in rural Bangladesh and to examine their relationship with haemoglobin (Hb) levels. A cross-sectional study. Girls' high schools in rural areas of Dhaka District in Bangladesh. Three hundred and ten anaemic adolescent girls aged 14-18 years from eight schools participated in the study. Information on personal characteristics and food habits were collected by interview. Parents were asked about their socio-economic conditions. Anthropometric data and blood samples were collected following the interview. Twenty-eight per cent of the girls had depleted iron stores (serum ferritin <12.0 microg/l), 25% had folic acid deficiency (red blood cell folic acid <317 nmol/l), 89% had vitamin B(2) (erythrocyte glutathione reductase activity coefficient > or =1.4) and 7% had vitamin B(12) deficiencies (serum vitamin B(12) <150 pmol/l). Although the prevalence of vitamins A and C deficiency was very low, a significant proportion had low vitamin A (serum retinol between 0.70 and <1.05 micromol/l) and vitamin C status (plasma ascorbic acid between 11.4-23.0 micromol/l). Frequency of consumption of meat, serum ferritin and vitamin B(2) status were found to be strongly related to Hb by multiple regression analysis. For 1 microg/l change in serum ferritin, there was a 0.13 g/l change in Hb when adjusted for other factors. There is coexistence of micronutrient deficiencies among anaemic adolescent girls in rural Bangladesh, although they do not suffer from energy deficiency. Of all micronutrients, only iron and vitamin B(2) concentrations were found to be related to the Hb concentration.

Serum vitamin E, C and A status of the drug addicts undergoing detoxification: influence of drug habit, sexual practice and lifestyle factors.

PubMed

Nazrul Islam, S K; Jahangir Hossain, K; Ahsan, M

2001-11-01

The study was carried out on the hypothesis that drug addicts would have reduced vitamin E, C and A status which could be influenced by drug habit, sexual practice and lifestyle factors. Serum concentrations of Vitamin E, C and A of male drug addicts and cohort controls were analysed, and influence of drug habit, sexual practice and lifestyle factors of the addicts on the vitamin status was assessed. The study was conducted among 253 drug addicts who sought detoxification voluntarily during the period of June 1997 to July 1998 at the Central Drug Addiction Treatment Hospital, Dhaka, and 100 cohort control men. Research instruments were questionnaire and blood specimens. HPLC and spectrophotometric methods were used to determine the vitamin levels in sera of drug addicts. alpha-Tocopherol (12.60+/-3.73 compared with 16.3+/-3.37 micromol/l; t=8.6, P=0.05), ascorbic acid (21.59+/-10.5 compared with 38.3+/-13.62 micromol/l; t=10.93, P=0.003) and retinol (1.15+/-0.39 compared with 1.33+/-0.30 micromol/l; t=5.28, P=0.048) in the drug addicts were significantly low as compared to those in the cohort controls. Use of multiple illicit drugs for a longer period of time did result in reduced levels of these vitamins. A significant reduction in retinol concentration was noted among the multiple drug users (F(2,250)=3.23, P=0.041). Duration of addiction had a significant linear correlation with the level of reduction in retinol (F(2,250)=3.23, P=0.041) and alpha-tocopherol (F(2,250)=3.06, P=0.049). Apart from having a significant negative correlation between number of sexual partners and retinol level (F(3,247)=2.65, P=0.049), sexual practice did not have any influence on the vitamin status of the addicts. Occupation did have a significant effect on the ascorbic acid level (F(4,248)=2.46, P=0.046), but other socioeconomic factors like income, age etc did not influence the vitamin E, C and A levels. Body mass index had a positive linear correlation with the vitamins, but it was significant only with vitamin C (F(2,250)=7.06, P=0.001). These results could have important implications for providing an antioxidant therapy to drug addicts and thus rehabilitating them into normal life. Risk of HIV infection and transmission (if any) could be reduced or inhibited.

Increasing Vitamin C Content in Plant Foods to Improve Their Nutritional Value—Successes and Challenges

PubMed Central

Gallie, Daniel R.

2013-01-01

Vitamin C serves as a cofactor in the synthesis of collagen needed to support cardiovascular function, maintenance of cartilage, bones, and teeth, as well as being required in wound healing. Although vitamin C is essential, humans are one of the few mammalian species unable to synthesize the vitamin and must obtain it through dietary sources. Only low levels of the vitamin are required to prevent scurvy but subclinical vitamin C deficiency can cause less obvious symptoms such as cardiovascular impairment. Up to a third of the adult population in the U.S. obtains less than the recommended amount of vitamin C from dietary sources of which plant-based foods constitute the major source. Consequently, strategies to increase vitamin C content in plants have been developed over the last decade and include increasing its synthesis as well as its recycling, i.e., the reduction of the oxidized form of ascorbic acid that is produced in reactions back into its reduced form. Increasing vitamin C levels in plants, however, is not without consequences. This review provides an overview of the approaches used to increase vitamin C content in plants and the successes achieved. Also discussed are some of the potential limitations of increasing vitamin C and how these may be overcome. PMID:23999762

Increasing vitamin C content in plant foods to improve their nutritional value-successes and challenges.

PubMed

Gallie, Daniel R

2013-08-30

Vitamin C serves as a cofactor in the synthesis of collagen needed to support cardiovascular function, maintenance of cartilage, bones, and teeth, as well as being required in wound healing. Although vitamin C is essential, humans are one of the few mammalian species unable to synthesize the vitamin and must obtain it through dietary sources. Only low levels of the vitamin are required to prevent scurvy but subclinical vitamin C deficiency can cause less obvious symptoms such as cardiovascular impairment. Up to a third of the adult population in the U.S. obtains less than the recommended amount of vitamin C from dietary sources of which plant-based foods constitute the major source. Consequently, strategies to increase vitamin C content in plants have been developed over the last decade and include increasing its synthesis as well as its recycling, i.e., the reduction of the oxidized form of ascorbic acid that is produced in reactions back into its reduced form. Increasing vitamin C levels in plants, however, is not without consequences. This review provides an overview of the approaches used to increase vitamin C content in plants and the successes achieved. Also discussed are some of the potential limitations of increasing vitamin C and how these may be overcome.

Vitamin E and selenium interrelations in the diet of Atlantic salmon (Salmo salar): Gross, histological and biochemical deficiency signs

USGS Publications Warehouse

Poston, Hugh A.; Combs, G.F.; Leibovitz, Louis

1976-01-01

Either simultaneous or separate dietary deficiencies of vitamin E and selenium in Atlantic salmon during first 4 weeks of feeding caused twice the mortality shown in fish fed both supplemental vitamin E (0.5 IU/g dry diet) and selenium (0.1 µg/g). Subsequent dietary repletion with both vitamin E and selenium significantly reduced mortality during the following 2 weeks. Larger salmon (0.9 g initial mean weight), with vitamin E deficiency with or without selenium resulted in the following deficiency signs: extreme anemia, pale gills, anisocytosis, poikilocytosis, elevated plasma protein, exudative diathesis, dermal depigmentation, in vitro ascorbic acid-stimulated peroxidation in hepatic microsomes, yellow-orange liver color, yellow-brown intestinal contents, enlarged gall bladder distended with dark green bile, low vitamin E in carcass and hepatic tissue, muscular dystrophy, increased carcass fat and water, and a response to handling characterized by a transitory fainting with interruption in swimming. A deficiency of dietary selenium suppressed plasma glutathione peroxidase activity. Supplemental selenium with vitamin E significantly increased tocopherol activity in hepatic, but not carcass tissues. Supplements of both vitamin E and selenium were necessary to prevent muscular dystrophy.

Depressed antioxidant status in pregnant women on iron supplements: pathologic and clinical correlates.

PubMed

Anetor, J I; Ajose, O A; Adeleke, F N; Olaniyan-Taylor, G O; Fasola, F A

2010-08-01

Iron (Fe) remains a commonly prescribed supplement in pregnancy. Its possible pathologic potential is either uncommonly considered or ignored. We determined the antioxidant status in pregnant women with and without Fe supplements. Fifty-eight apparently healthy pregnant women on Fe supplements were selected for the study from the antenatal clinic of the University College Hospital, Ibadan, Nigeria. Fifty-five aged matched pregnant women who were not on Fe from various parishes of the Christ Apostolic Church, Ibadan (non-drug using Christian sect) were randomly selected as controls. Both groups were classified according to the trimesters of pregnancy. The gestational age in both pregnant women on Fe supplements and non-supplement pregnant women was similar. Fruit and vegetables consumption was higher in the supplement than in the non-supplement group (57.2% vs. 37.3%). Anthropometric indices, weight, height, and BMI, were also similar. But while the weight of the Fe supplement group decreased by nearly 3% in the third trimester, it increased by over 10% (p < 0.00) in the non-supplement group in the same period. Serum Fe level was significantly higher in the supplement than the non-supplement group (p < 0.001). In contrast, the levels of the antioxidants, ascorbic acid, copper (Cu), zinc (Zn), and bilirubin were all significantly decreased (p < 0.05, p < 0.001, p < 0.05, and p < 0.05, respectively). Uric acid level though also lower in the supplement group did not reach statistical significance (p > 0.05), while vitamin E was similar in both groups. There was relative stability of all antioxidants except uric acid, which declined from the first to the last trimester in the non-supplement group. The significantly higher Fe level in the second trimester was sustained in the third trimester though to a lesser degree (p < 0.05) and associated with significant decreases in the following antioxidant levels in the supplement group, ascorbic acid, bilirubin, Cu, and Zn (p < 0.02, p < 0.02, p < 0.02, and p < 0.001, respectively). Uric acid and vitamin E though lower in the supplement group were not significantly different. Remarkably, percentage changes between the first and third trimesters revealed that serum Fe increased by over 116% in the Fe supplement group, while it only increased by over 50% in the non-supplement group. This was associated with 23.50% decrease in ascorbate level (p < 0.003) in the supplement group, while it decreased by only 3.70% in the non-supplement group (p > 0.05). Again vitamin E decreased by 17.22% in the supplement group, while it decreased by only 7.30% in the non-supplement group during the period. Uric acid and bilirubin levels decreased by similar proportions during the period, while Zn decreased by 18.55% in the supplement group and by 14.86% in the non-supplement group. In contrast Cu increased by 7.20% in the supplement group, while it increased by only 2.96 in the non-supplement group. Additionally, all the antioxidants in the supplement group except vitamin E, viz, ascorbic acid, bilirubin, Cu, uric acid, and Zn, were significantly inversely correlated with serum Fe level (r - 0.299, p < 0.05, r - 0.278, p < 0.05, r - 0.383, p < 0.05, and r - 0.0369, p < 0.05). These data imply markedly depressed antioxidant status in the Fe supplement pregnant group with attendant oxidative stress (most probably pro-oxidant Fe-induced). This is associated with molecular and cellular damage as well as a number of pathologic and clinical correlates that underlie the exacerbation of morbidity and mortality in maternal and child populations, particularly in the developing countries. This appears to call for serious caution and prior evaluation of antioxidant and Fe status and during the use of Fe supplements in pregnancy for monitoring and prognostic purposes and to avert or ameliorate oxidative stress-induced pathologies in maternal and fetal systems.

Intracellular Ascorbate Prevents Endothelial Barrier Permeabilization by Thrombin*

PubMed Central

Parker, William H.; Qu, Zhi-chao; May, James M.

2015-01-01

Intracellular ascorbate (vitamin C) has previously been shown to tighten the endothelial barrier and maintain barrier integrity during acute inflammation in vitro. However, the downstream effectors of ascorbate in the regulation of endothelial permeability remain unclear. In this study, we evaluated ascorbate as a mediator of thrombin-induced barrier permeabilization in human umbilical vein endothelial cells and their immortalized hybridoma line, EA.hy926. We found that the vitamin fully prevented increased permeability to the polysaccharide inulin by thrombin in a dose-dependent manner, and it took effect both before and after subjection to thrombin. Thrombin exposure consumed intracellular ascorbate but not the endogenous antioxidant GSH. Likewise, the antioxidants dithiothreitol and tempol did not reverse permeabilization. We identified a novel role for ascorbate in preserving cAMP during thrombin stimulation, resulting in two downstream effects. First, ascorbate maintained the cortical actin cytoskeleton in a Rap1- and Rac1-dependent manner, thus preserving stable adherens junctions between adjacent cells. Second, ascorbate prevented actin polymerization and formation of stress fibers by reducing the activation of RhoA and phosphorylation of myosin light chain. Although ascorbate and thrombin both required calcium for their respective effects, ascorbate did not prevent thrombin permeabilization by obstructing calcium influx. However, preservation of cAMP by ascorbate was found to depend on both the production of nitric oxide by endothelial nitric-oxide synthase, which ascorbate is known to activate, and the subsequent generation cGMP by guanylate cyclase. Together, these data implicate ascorbate in the prevention of inflammatory endothelial barrier permeabilization and explain the underlying signaling mechanism. PMID:26152729

Ascorbate supplementation inhibits growth and metastasis of B16FO melanoma and 4T1 breast cancer cells in vitamin C-deficient mice.

PubMed

Cha, John; Roomi, M Waheed; Ivanov, Vadim; Kalinovsky, Tatiana; Niedzwiecki, Aleksandra; Rath, Matthias

2013-01-01

Degradation of the extracellular matrix (ECM) plays a critical role in the formation of tumors and metastasis and has been found to correlate with the aggressiveness of tumor growth and invasiveness of cancer. Ascorbic acid, which is known to be essential for the structural integrity of the intercellular matrix, is not produced by humans and must be obtained from the diet. Cancer patients have been shown to have very low reserves of ascorbic acid. Our main objective was to determine the effect of ascorbate supplementation on metastasis, tumor growth and tumor immunohistochemistry in mice unable to synthesize ascorbic acid [gulonolactone oxidase (gulo) knockout (KO)] when challenged with B16FO melanoma or 4T1 breast cancer cells. Gulo KO female mice 36-38 weeks of age were deprived of or maintained on ascorbate in food and water for 4 weeks prior to and 2 weeks post intraperitoneal (IP) injection of 5x105 B16FO murine melanoma cells or to injection of 5x105 4T1 breast cancer cells into the mammary pad of mice. Ascorbate-supplemented gulo KO mice injected with B16FO melanoma cells demonstrated significant reduction (by 71%, p=0.005) in tumor metastasis compared to gulo KO mice on the control diet. The mean tumor weight in ascorbate supplemented mice injected with 4T1 cells was reduced by 28% compared to tumor weight in scorbutic mice. Scorbutic tumors demonstrated large dark cores, associated with increased necrotic areas and breaches to the tumor surface, apoptosis and matrix metalloproteinase-9 (MMP-9), and weak, disorganized or missing collagen I tumor capsule. In contrast, the ascorbate-supplemented group tumors had smaller fainter colored cores and confined areas of necrosis/apoptosis with no breaches from the core to the outside of the tumor and a robust collagen I tumor capsule. In both studies, ascorbate supplementation of gulo KO mice resulted in profoundly decreased serum inflammatory cytokine interleukin (IL)-6 (99% decrease, p=0.01 in the B16F0 study and 85% decrease, p=0.08 in the 4T1 study) compared to the levels in gulo KO mice deprived of ascorbate. In the B16FO study, ascorbate supplementation of gulo KO mice resulted in profoundly decreased serum VEGF (98% decrease, p=0.019 than in the scorbutic gulo KO mice). As expected, mean serum ascorbate level in ascorbate-restricted mice was 2% (p<0.001) of the mean ascorbate levels in supplemented mice. In conclusion, ascorbate supplementation hinders metastasis, tumor growth and inflammatory cytokine secretion as well as enhanced encapsulation of tumors elicited by melanoma and breast cancer cell challenge in gulo KO mice.

Multicomponent analysis of fat- and water-soluble vitamins and auxiliary substances in multivitamin preparations by qNMR.

PubMed

Eiff, Julia; Monakhova, Yulia B; Diehl, Bernd W K

2015-04-01

A nuclear magnetic resonance (NMR) spectroscopic method was tested to control 12 vitamins and accompanying substances in multivitamin preparations. The limits of detection (LODs) and limits of quantification (LOQs) varied in the 9.0-77.0 mg/kg and in the 34.5-93.5 mg/kg range, respectively. The coefficients of variation (CVs) ranged between 0.9% and 12%. The (1)H NMR spectra showed linearity for the 140-260 mg sample weight (R(2) > 0.918). The NMR spectra of multivitamin preparations showed the presence of different degradation products of ascorbic acid. The NMR method was applied to 13 different multivitamin preparations including tablets, capsules, and effervescent tablets with average recovery rates between 85% and 132%. A number of accompanying substances (citric acid, mannitol, saccharin, cyclamate, sum of steviol glycosides, and butylhydroxytoluene) were additionally identified and quantified. NMR was found to be suitable for the simultaneous qualitative measurement of water- and fat-soluble vitamins and accompanying substances and shows some promise for quantitative determination of at least 5 vitamins (B1, B3, B5, B6, and E) in multivitamin preparations.

Effect of vitamin C supplements on urinary oxalate and pH in calcium stone-forming patients.

PubMed

Baxmann, Alessandra Calábria; De O G Mendonça, Claudia; Heilberg, Ita Pfeferman

2003-03-01

The contribution of ascorbate to urinary oxalate is controversial. The present study aimed to determine whether urinary oxalate and pH may be affected by vitamin C supplementation in calcium stone-forming patients. Forty-seven adult calcium stone-forming patients received either 1 g (N=23) or 2 g (N=24) of vitamin C supplement for 3 days and 20 healthy subjects received 1 g. A 24-hour urine sample was obtained both before and after vitamin C for calcium, oxalate, magnesium, citrate, sodium, potassium, and creatinine determination. The Tiselius index was used as a calcium oxalate crystallization index. A spot fasting morning urine sample was also obtained to determine the urinary pH before and after vitamin C. Fasting urinary pH did not change after 1 g (5.8 +/- 0.6 vs. 5.8 +/- 0.7) or 2 g vitamin C (5.8 +/- 0.8 vs. 5.8 +/- 0.7). A significant increase in mean urinary oxalate was observed in calcium stone-forming patients receiving either 1 g (50 +/- 16 vs. 31 +/- 12 mg/24 hours) or 2 g (48 +/- 21 vs. 34 +/- 12 mg/24 hours) of vitamin C and in healthy subjects (25 +/- 12 vs. 39 +/- 13 mg/24 hours). A significant increase in mean Tiselius index was observed in calcium stone-forming patients after 1 g (1.43 +/- 0.70 vs. 0.92 +/- 0.65) or 2 g vitamin C (1.61 +/- 1.05 vs. 0.99 +/- 0.55) and in healthy subjects (1.50 +/- 0.69 vs. 0.91 +/- 0.46). Ancillary analyses of spot urine obtained after vitamin C were performed in 15 control subjects in vessels with or without ethylenediaminetetraacetic acid (EDTA) with no difference in urinary oxalate between them (28 +/- 23 vs. 26 +/- 21 mg/L), suggesting that the in vitro conversion of ascorbate to oxalate did not occur. These data suggest that vitamin C supplementation may increase urinary oxalate excretion and the risk of calcium oxalate crystallization in calcium stone-forming patients.

Hydrosoluble vitamins.

PubMed

Chawla, Jasvinder; Kvarnberg, David

2014-01-01

The hydrosoluble vitamins are a group of organic substances that are required by humans in small amounts to prevent disorders of metabolism. Significant progress has been made in our understanding of the biochemical, physiologic and nutritional aspects of the water-soluble vitamins. Deficiency of these particular vitamins, most commonly due to inadequate nutrition, can result in disorders of the nervous system. Many of these disorders have been successfully prevented in developed countries; however, they are still common in developing countries. Of the hydrosoluble vitamins, the nervous system depends the most on vitamins B and C (ascorbic acid) for proper functioning. The B group vitamins include thiamin (vitamin B1), riboflavin (vitamin B2), niacin or niacinamide (vitamin B3), pantothenic acid (vitamin B5), pyridoxine or pyridoxal (vitamin B6) and cobalamin (vitamin B12). Clinical findings depend upon the deficiency of the underlying vitamin; generally, deficiency symptoms are seen from a combination rather than an isolated vitamin deficiency. True hereditary metabolic disorders and serious deficiency-associated diseases are rare and in general limited to particular geographic regions and high-risk groups. Their recognition is truly important as that determines the appropriate therapeutic management. The general availability of vitamins to practically everyone and several national health programs have saved many lives and prevented complications. However, there has been some apprehension for several decades about how harmless generous dosages of these vitamins are. Overt overdosages can cause vitamin toxicity affecting various body systems including the nervous system. Systemically, vitamin toxicity is associated with nonspecific symptoms, such as nausea, vomiting, diarrhea, and skin rash which are common with any acute or chronic vitamin overdose. At a national level, recommended daily allowances for vitamins become policy statements. Nutrition policy has far reaching implications in the food industry, in agriculture, and in food provision programs. Overall, water-soluble vitamins are complex molecular structures and even today, many areas of vitamin biochemistry still need to be explored. Many readers might be of the opinion that the classic forms of nutritional deficiency diseases have faded into the background of interesting history. This has caused their diverse symptoms to be neglected by most modern physicians since vitamin enrichment of many foods automatically erases them from their consideration in differential diagnosis. Vitamin B12 and folic acid deficiencies are discussed in other chapters. © 2014 Elsevier B.V. All rights reserved.

The oxidized form of vitamin C, dehydroascorbic acid, regulates neuronal energy metabolism.

PubMed

Cisternas, Pedro; Silva-Alvarez, Carmen; Martínez, Fernando; Fernandez, Emilio; Ferrada, Luciano; Oyarce, Karina; Salazar, Katterine; Bolaños, Juan P; Nualart, Francisco

2014-05-01

Vitamin C is an essential factor for neuronal function and survival, existing in two redox states, ascorbic acid (AA), and its oxidized form, dehydroascorbic acid (DHA). Here, we show uptake of both AA and DHA by primary cultures of rat brain cortical neurons. Moreover, we show that most intracellular AA was rapidly oxidized to DHA. Intracellular DHA induced a rapid and dramatic decrease in reduced glutathione that was immediately followed by a spontaneous recovery. This transient decrease in glutathione oxidation was preceded by an increase in the rate of glucose oxidation through the pentose phosphate pathway (PPP), and a concomitant decrease in glucose oxidation through glycolysis. DHA stimulated the activity of glucose-6-phosphate dehydrogenase, the rate-limiting enzyme of the PPP. Furthermore, we found that DHA stimulated the rate of lactate uptake by neurons in a time- and dose-dependent manner. Thus, DHA is a novel modulator of neuronal energy metabolism by facilitating the utilization of glucose through the PPP for antioxidant purposes. © 2014 International Society for Neurochemistry.

Quality changes of pasteurised orange juice during storage: A kinetic study of specific parameters and their relation to colour instability.

PubMed

Wibowo, Scheling; Grauwet, Tara; Santiago, Jihan Santanina; Tomic, Jovana; Vervoort, Liesbeth; Hendrickx, Marc; Van Loey, Ann

2015-11-15

In view of understanding colour instability of pasteurised orange juice during storage, to the best of our knowledge, this study reports for the first time in a systematic and quantitative way on a range of changes in specific quality parameters as a function of time and as well as temperature (20-42 °C). A zero-order (°Brix, fructose, glucose), a first-order (vitamin C), a second-order (sucrose) and a fractional conversion model (oxygen) were selected to model the evolution of the parameters between parentheses. Activation energies ranged from 22 to 136 kJ mol(-1), HMF formation being the most temperature sensitive. High correlations were found between sugars, ascorbic acid, their degradation products (furfural and HMF) and total colour difference (ΔE(∗)). Based on PLS regression, the importance of the quality parameters for colour degradation was ranked relatively among each other: the acid-catalysed degradation of sugars and ascorbic acid degradation reactions appeared to be important for browning development in pasteurised orange juice during ambient storage. Copyright © 2015 Elsevier Ltd. All rights reserved.

An In Vitro Skin Equivalent for Evaluation of Skin Absorption of Compounds

DTIC Science & Technology

2008-12-01

1023-1033. Uchida, Y., M. Behne, D. Quiec, P. M. Elias, and W. M. Holleran, 2001: Vitamin C Stimulates Sphingolipid Production and Markers of...dermal fibroblasts and human keratinocytes, and conditions such as addition of ascorbic acid are being used to look at effects on morphogenesis...and Epiderm FT ® (Full thickness SE) (MatTek Corporation, Ashland MA, USA) (Bernard, F.- X., Barrault, C . et al. 2000;Boelsma, E., Gibbs, S. et al

A study of effective atomic numbers and electron densities of some vitamins for electron, H, He and C ion interactions

NASA Astrophysics Data System (ADS)

Büyükyıldız, M.

2017-09-01

The radiological properties of some vitamins such as Retinol, Beta-carotene, Riboflavin, Niacin, Niacinamide, Pantothenic acid, Pyridoxine, Pyridoxamine, Pyridoxal, Biotin, Folic acid, Ascorbic acid, Cholecalciferol, Alpha-tocopherol, Gamma-tocopherol, Phylloquinone have been investigated with respect to total electron interaction and some heavy charged particle interaction as means of effective atomic numbers (Z_{eff}) and electron densities (N_{eff}) for the first time. Calculations were performed for total electron interaction and heavy ions such as H, He and C ion interactions in the energy region 10keV-10MeV by using a logarithmic interpolation method. Variations in Z_{eff}'s and N_{eff}'s of given vitamins have been studied according to the energy of electron or heavy charged particles, and significant variations have been observed for all types of interaction in the given energy region. The maximum values of Z_{eff} have been found in the different energy regions for different interactions remarkably and variations in N_{eff} seem approximately to be the same with variation in Z_{eff} for the given vitamins as expected. Z_{eff} values of some vitamins were plotted together and compared with each other for electron, H, He and C interactions and the ratios of Z_{eff}/ < A > have been changed in the range of 0.25-0.36, 0.20-0.36, 0.22-0.35 and 0.20-0.35 for electron, H, He and C interactions, respectively.

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.

Effect of water soluble vitamins on Zn transport of Caco-2 cells and their implications under oxidative stress conditions.

PubMed

Tupe, Rashmi Santosh; Agte, Vaishali Vilas

2010-02-01

The role of different water soluble vitamins in Zn metabolism beyond intestinal Zn absorption is poorly explored. Using Caco-2 cells, effects of different vitamins on intestinal Zn transport and their implications under oxidative stress (OS) were investigated. Cells were apically treated with Zn (25 muM) and vitamins (Folic acid (FA), Nicotinic acid (NA), Ascorbic acid (AA), riboflavin, thiamine, pyridoxine) for 60 min. The effect of most promising vitamins on zinc transport, antioxidant enzymes (Catalase, Glutathione peroxidase, and superoxide dismutase), and intracellular OS status (ROS generation and mitochondrial transmembrane potential) were investigated. OS was generated by tert-butyl hydro peroxide and results for each vitamin were compared with respective Zn containing controls with and without OS. Without OS, Zn transport was slightly enhanced in presence of NA, while it was significantly reduced by thiamine, riboflavin, and pyridoxine. Under OS, NA significantly (P < 0.01) enhanced Zn transport in dose-dependent manner, while, pyridoxine and AA moderately improved it. Under both conditions, Zn transport exhibited decreasing trend with increase of FA. The antioxidant enzyme and OS markers levels varied significantly in Zn + vitamins. With Zn + FA + OS, enzyme activities decreased maximally, with twofold increase in 2',7'-dichlorofluorescin diacetate (DCF-DA) (P < 0.01) and lowering of rhodamine fluorescence (P < 0.05). In Zn + AA + OS, DCF-DA fluorescence increased (P < 0.05) but with NA, cellular enzymes, and antioxidant profile were improved. Results for the first time demonstrate advantageous effects of NA and deleterious consequences of FA with no effect by AA on Zn transport, especially under OS. These observed changes in the transport of Zn seem to have an impact on OS markers.

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 of Food Technologists®

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.

Changes in phytochemical and antioxidant activity of selected pepper cultivars (Capsicum species) as influenced by maturity.

PubMed

Howard, L R; Talcott, S T; Brenes, C H; Villalon, B

2000-05-01

The effect of fruit maturation on changes in carotenoids, flavonoids, total soluble reducing equivalents, phenolic acids, ascorbic acid, and antioxidant activity (AOX) in different pepper types (Capsicum annuum, Capsicum frutescens, and Capsicum chinese) was determined. Generally, the concentration of these chemical constituents increased as the peppers reached maturity. Peppers contained high levels of L-ascorbic acid and carotenoids at maturity, contributing 124-338% of the RDA for vitamin C and 0.33-336 RE/100 g of provitamin A activity, respectively. Levels of phenolic acids, capxanthin, and zeaxanthin generally increased during maturation, whereas the level of lutein declined. Flavonoid concentrations varied greatly among the pepper types analyzed and were negatively correlated to AOX under the conditions of the beta-carotene-linoleic assay. Model systems were used to aid in understanding the relationship between flavonoids and AOX. Significant increases in AOX were observed in pepper juice models in response to increasing dilution factors and the presence of EDTA, indicating a pro-oxidant effect due to metal ions in the system. In vitro models demonstrated that increasing levels of flavonoids in combination with constant levels of caffeic and ascorbic acid gave a resultant AOX that was either additive of the two compounds or competitive in their ability to scavenge peroxyl radicals. The model systems were in good agreement with the chemical composition of the pepper cultivars and reflected the interactions affecting AOX. More research is needed to understand the complex interactions that occur among various antioxidants present in pepper extracts.

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

Protection against radiation-induced oxidative stress in cultured human epithelial cells by treatment with antioxidant agents

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

Wan, X. Steven; Ware, Jeffrey H.; Zhou, Zhaozong

2006-04-01

Purpose: To evaluate the protective effects of antioxidant agents against space radiation-induced oxidative stress in cultured human epithelial cells. Methods and Materials: The effects of selected concentrations of N-acetylcysteine, ascorbic acid, sodium ascorbate, co-enzyme Q10, {alpha}-lipoic acid, L-selenomethionine, and vitamin E succinate on radiation-induced oxidative stress were evaluated in MCF10 human breast epithelial cells exposed to radiation with X-rays, {gamma}-rays, protons, or high mass, high atomic number, and high energy particles using a dichlorofluorescein assay. Results: The results demonstrated that these antioxidants are effective in protecting against radiation-induced oxidative stress and complete or nearly complete protection was achieved by treatingmore » the cells with a combination of these agents before and during the radiation exposure. Conclusion: The combination of antioxidants evaluated in this study is likely be a promising countermeasure for protection against space radiation-induced adverse biologic effects.« less

Protection of ascorbic acid from copper(II)-catalyzed oxidative degradation in the presence of flavonoids: quercetin, catechin and morin.

PubMed

Beker, Bilge Yildoğan; Sönmezoğlu, Inci; Imer, Filiz; Apak, Reşat

2011-08-01

Protection of ascorbic acid (AA) (vitamin C) from Cu(II)-catalyzed autoxidation is an important aspect of antioxidant chemistry. The autoxidation of AA in the absence and presence of Cu(II) ions was investigated in aerated solution at room temperature and I = 0.1 ionic strength (KNO(3)); the effects of three different flavonoids of similar structure (quercetin, morin and catechin) and their mixtures on the AA system were studied. The concentration of unoxidized AA remaining in solution was measured with the modified cupric ion reducing antioxidant capacity spectrophotometric method. The Cu(II)-catalyzed oxidation at pH 4.5 followed first-order kinetics with respect to AA concentration. Catalytic autoxidation of AA was inhibited to a greater extent by stable quercetin and morin complexes of Cu(II) than by catechin complex. The inhibitive effectiveness order of mixtures gives information about possible synergistic or antagonistic combinations of flavonoid antioxidants, which should be further confirmed with other antioxidant tests.

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.

Lycium Barbarum: A Traditional Chinese Herb and A Promising Anti-Aging Agent

PubMed Central

Gao, Yanjie; Wei, Yifo; Wang, Yuqing; Gao, Fang; Chen, Zhigang

2017-01-01

Lycium barbarum has been used in China for more than 2,000 years as a traditional medicinal herb and food supplement. Lycium barbarum contains abundant Lycium barbarum polysaccharides (LBPs), betaine, phenolics, carotenoids (zeaxanthin and β-carotene), cerebroside, 2-O-β-d-glucopyranosyl-l-ascorbic acid (AA-2βG), β-sitosterol, flavonoids and vitamins (in particular, riboflavin, thiamine, and ascorbic acid). LBPs are the primary active components of Lycium barbarum. In this review, we discuss the pharmacological activities of LBPs and other major components. They have been reported to mediate significant anti-aging effects, through antioxidant, immunoregulative, anti-apoptotic activities and reducing DNA damage. Thus, the basic scientific evidence for anti-aging effects of LBPs is already available. However, additional studies are needed to understand mechanisms by which LBPs mediate anti-aging properties. Novel findings from such studies would likely pave the way for the clinical application of traditional chinese medicine Lycium barbarum in modern evidence-based medicine. PMID:29344416

Intracellular Ascorbate Prevents Endothelial Barrier Permeabilization by Thrombin.

PubMed

Parker, William H; Qu, Zhi-chao; May, James M

2015-08-28

Intracellular ascorbate (vitamin C) has previously been shown to tighten the endothelial barrier and maintain barrier integrity during acute inflammation in vitro. However, the downstream effectors of ascorbate in the regulation of endothelial permeability remain unclear. In this study, we evaluated ascorbate as a mediator of thrombin-induced barrier permeabilization in human umbilical vein endothelial cells and their immortalized hybridoma line, EA.hy926. We found that the vitamin fully prevented increased permeability to the polysaccharide inulin by thrombin in a dose-dependent manner, and it took effect both before and after subjection to thrombin. Thrombin exposure consumed intracellular ascorbate but not the endogenous antioxidant GSH. Likewise, the antioxidants dithiothreitol and tempol did not reverse permeabilization. We identified a novel role for ascorbate in preserving cAMP during thrombin stimulation, resulting in two downstream effects. First, ascorbate maintained the cortical actin cytoskeleton in a Rap1- and Rac1-dependent manner, thus preserving stable adherens junctions between adjacent cells. Second, ascorbate prevented actin polymerization and formation of stress fibers by reducing the activation of RhoA and phosphorylation of myosin light chain. Although ascorbate and thrombin both required calcium for their respective effects, ascorbate did not prevent thrombin permeabilization by obstructing calcium influx. However, preservation of cAMP by ascorbate was found to depend on both the production of nitric oxide by endothelial nitric-oxide synthase, which ascorbate is known to activate, and the subsequent generation cGMP by guanylate cyclase. Together, these data implicate ascorbate in the prevention of inflammatory endothelial barrier permeabilization and explain the underlying signaling mechanism. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

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.

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.

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.

Influence of vitamin C and vitamin E on redox signaling: Implications for exercise adaptations.

PubMed

Cobley, James N; McHardy, Helen; Morton, James P; Nikolaidis, Michalis G; Close, Graeme L

2015-07-01

The exogenous antioxidants vitamin C (ascorbate) and vitamin E (α-tocopherol) often blunt favorable cell signaling responses to exercise, suggesting that redox signaling contributes to exercise adaptations. Current theories posit that this antioxidant paradigm interferes with redox signaling by attenuating exercise-induced reactive oxygen species (ROS) and reactive nitrogen species (RNS) generation. The well-documented in vitro antioxidant actions of ascorbate and α-tocopherol and characterization of the type and source of the ROS/RNS produced during exercise theoretically enable identification of redox-dependent mechanisms responsible for the blunting of favorable cell signaling responses to exercise. This review aimed to apply this reasoning to determine how the aforementioned antioxidants might attenuate exercise-induced ROS/RNS production. The principal outcomes of this analysis are (1) neither antioxidant is likely to attenuate nitric oxide signaling either directly (reaction with nitric oxide) or indirectly (reaction with derivatives, e.g., peroxynitrite); (2) neither antioxidant reacts appreciably with hydrogen peroxide, a key effector of redox signaling; (3) ascorbate but not α-tocopherol has the capacity to attenuate exercise-induced superoxide generation; and (4) alternate mechanisms, namely pro-oxidant side reactions and/or reduction of bioactive oxidized macromolecule adducts, are unlikely to interfere with exercise-induced redox signaling. Out of all the possibilities considered, ascorbate-mediated suppression of superoxide generation with attendant implications for hydrogen peroxide signaling is arguably the most cogent explanation for blunting of favorable cell signaling responses to exercise. However, this mechanism is dependent on ascorbate accumulating at sites rich in NADPH oxidases, principal contributors to contraction-mediated superoxide generation, and outcompeting nitric oxide and superoxide dismutase isoforms. The major conclusions of this review are: (1) direct evidence for interference of ascorbate and α-tocopherol with exercise-induced ROS/RNS production is lacking; (2) theoretical analysis reveals that both antioxidants are unlikely to have a major impact on exercise-induced redox signaling; and (3) it is worth considering alternate redox-independent mechanisms. Copyright © 2015 Elsevier Inc. All rights reserved.

Moisturizing potentials of ascorbyl palmitate and calcium ascorbate in various topical formulations.

PubMed

Gönüllü, U; Yener, G; Uner, M; Incegül, T

2004-02-01

The aim of this study was to use two of Vitamin C derivatives, lipophilic ascorbyl palmitate and hydrophilic calcium ascorbate to determine their skin-hydrating effects for the first time. For this purpose, anhydrous cream, gel and w/o emulsion were prepared and applied to the volunteers' inner forearms. A commercial topical preparation containing a known moisturizer, Vitamin E, was also chosen and used for comparison. Moisture contents of the skin were measured by using corneometer.

[Vitamin status of citizens from Moscow Region].

PubMed

Beketova, N A; Pogozheva, A V; Kodentsova, V M; Vrzhesinskaya, O A; Kosheleva, O V; Pereverzeva, O G; Aristarhova, T V; Levin, L G; Danisova, N N; Baturin, A K

2016-01-01

Evaluation of vitamin status in healthy individuals (68 men and 70 women) aged from 18 to 60 years (median - 37 years), residents of Moscow and the Moscow region has been performed by means of determination of vitamin C, A, E, B2, B12 and folic acid level in blood serum. The nutrition was investigated by questionnaire method on frequency of food consumption. Both diet of men and women had excessive fat content (41.7 and 42.7% of total calories), saturated fatty acids (14.1 and 13.6%), added sugars (11.1 and 11.0%), sodium, and had lack of dietary fiber (2.5-fold reduced level comparing with RDA). Daily intake of vitamin B1 was 1.37±0.04 mg for men and 1.06±0.07 mg for women, vitamin B2 - respectively 1.72±0.06 and 1.62±0.07 mg, niacin - 18.5±0.72 and 14.8±0.88 mg and did not reach the optimal level. All persons were sufficiently supplied with vitamins A, C, E and B12: mean and median of blood serum level of retinol, tocopherols, ascorbic acid and cobalamins were in the range of optimum values. The lack of vitamins A and B12 has not been found in any person. The frequency of vitamin C and E insufficiency was insignificant and amounted to 2 and 8% respectively. The lack of vitamin B2, and β-carotene was most pronounced and took place in about a half of individuals. Only 34% of healthy people of working age were sufficiently supplied with all vitamins. A combined lack of two vitamins was detected in 26%, of three vitamins - in 8%. Women were better supplied with riboflavin and β-carotene. The blood serum level of β-carotene and vitamin E was significantly higher in individuals older than 30 years compared with persons of younger age. Individuals with overweight or obesity were worse supplied with β-carotene and folate. A negative correlation was detected between the levels of serum folate and homocysteine concentration (r=-0.262, p<0.05). A positive correlation has been revealed between the concentration of folic acid and the level of HDL-C (r=0.356, p<0.01), and iron (r=0.378, p<0.05).

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.

The Effects of Various Levels of Ascorbic Acid Intake Upon Oral Wound Healing in Guinea Pigs.

DTIC Science & Technology

1983-01-01

82174 7’ 4 8 Alfano observed increased permeability of oral tissue with decreased vitamin C supplementation. Periodontal tissues are susceptible to...make a uniform wound in the midline of the oral mucosa, anterior to the maxillary premolars. (Figure 2). The trephine bur penetrated the tissues until...grids across the wound site and dividing by two. This area encompassed the edges of the bone wound or residual mature soft connective tissue . The

One-step green route to narrowly dispersed copper nanocrystals

NASA Astrophysics Data System (ADS)

Wu, Chunwei; Mosher, Brian P.; Zeng, Taofang

2006-12-01

We report a total "green" chemical method in aqueous solution for synthesizing stable narrowly distributed copper nanoparticles with average diameter less than 5 nm in the presence of Polyvinylpyrrolidone (PVP) as a stabilizer and without any inert gas protection. In our synthesis route, ascorbic acid, natural vitamin C (VC), an excellent oxygen scavenger, acts as both reducing agent and antioxidant, to reduce the metallic ion precursor, and to effectively prevent the common oxidation process of the newborn pure copper nanoclusters.

Microscale Determination of Vitamin C by Weight Titrimetry

NASA Astrophysics Data System (ADS)

East, Gaston A.; Nascimento, Erica C.

2002-01-01

A laboratory experiment involving the quantitative microscale determination of ascorbic acid in pharmaceutical tablets of vitamin C by weight-titrimetry using (diacetoxyiodo)benzene as titrant and differential electrolytic potentiometry to locate the end-point is presented. The experiment affords an opportunity for students to explore nonconventional techniques such as the use of a novel organic oxidimetric titrant, titration in a semiaqueous medium, gravimetric titration, and an electrometric method of end-point detection using polarized electrodes. Synthesis, purification, and purity checking of the titrant may also be included in the project. Some advantages of the method are very low reagent consumption, low-cost equipment, improved sensitivity, and high precision and accuracy. Furthermore, the experiment will help the student to relate chemical analysis to everyday life.

Efficacy of vitamin C against liver and kidney damage induced by paraquat toxicity.

PubMed

Awadalla, Eatemad A

2012-07-01

Paraquat has been demonstrated to be a highly toxic compound for humans and animals and many cases of acute poisoning and death have been reported over the past few decades. The current experiment aimed to examine if vitamin C (ascorbic acid) alleviates the morphological changes induced by paraquat (PQ) administration in the liver and kidney of male albino rats. Male adult rats received paraquat (PQ) (1.5 mg/kg body weight) daily for three weeks. Vitamin C (VC) at a dose of 20 mg/kg body weight was given concomitantly with PQ to rats. Animals were divided into three groups in this experiment (control, PQ and PQ+VC). The morphopathological manifestations were investigated in tissues from liver and kidney. As expected, PQ administration induced marked changes in the morphological structure of the liver and kidney in PQ demonstrated animals. Importantly, vitamin C administration restored PQ-induced changes in the studied organs. Vitamin C administration attenuated the morphological damages induced by PQ in the liver and kidney of experimental animals. Our results suggest an antitoxic effect of vitamin C against paraquat. Copyright © 2010 Elsevier GmbH. All rights reserved.

In silico aided thoughts on mitochondrial vitamin C transport.

PubMed

Szarka, András; Balogh, Tibor

2015-01-21

The huge demand of mitochondria as the quantitatively most important sources of ROS in the majority of heterotrophic cells for vitamin C is indisputable. The reduced form of the vitamin, l-ascorbic acid, is imported by an active mechanism requiring two sodium-dependent vitamin C transporters (SVCT1 and SVCT2). The oxidized form, dehydroascorbate is taken up by different members of the GLUT family. Because of the controversial experimental results the picture on mitochondrial vitamin C transport became quite obscure by the spring of 2014. Thus in silico prediction tools were applied in aid of the support of in vitro and in vivo results. The role of GLUT1 as a mitochondrial dehydroascorbate transporter could be reinforced by in silico predictions however the mitochondrial presence of GLUT10 is not likely since this transport protein got far the lowest mitochondrial localization scores. Furthermore the possible roles of GLUT9 and 11 in mitochondrial vitamin C transport can be proposed leastwise on the base of their computational localization analysis. In good concordance with the newest experimental observations on SVCT2 the mitochondrial presence of this transporter could also be supported by the computational prediction tools. Copyright © 2014 Elsevier Ltd. All rights reserved.

Simultaneous determination of some water-soluble vitamins and preservatives in multivitamin syrup by validated stability-indicating high-performance liquid chromatography method.

PubMed

Vidović, Stojanka; Stojanović, Biljana; Veljković, Jelena; Prazić-Arsić, Ljiljana; Roglić, Goran; Manojlović, Dragan

2008-08-22

HPLC stability-indicating method has been developed for the simultaneous determination of some water-soluble vitamins (ascorbic acid, thiamine hydrochloride, riboflavin-5'-phosphate sodium, pyridoxine hydrochloride, nicotinamide, D(+)-panthenol) and two preservatives (methylparaben and sodium benzoate) in multivitamin syrup preparation. Water-soluble vitamins, preservatives and their degradants were separated on Zorbax SB-Aq (C(18)) (250 mm x 4.6 mm, 5 microm) column at an ambient temperature. Combined isocratic and gradient elution was performed with a mobile phase consisting of 0.0125 M hexane-1-sulfonic acid sodium salt in 0.1% (m/v) o-phosphoric acid, pH 2.4-2.5 (solvent A) and acetonitrile (solvent B) at the flow-rate 1 ml min(-1). Starting with solvent A an isocratic elution was performed for 15 min, then the composition was changed to 85% of A and 15% of B during the next 20 min and it was constant for 5 min, then the composition was changed to 70% of A and 30% of B during next 15 min and it was constant for 5 min and finally was changed to 100% of A as at the beginning of the elution. Detection was performed with diode array detector at 210, 230 and 254 nm. Multivitamin syrup preparation was subjected to stress testing (forced degradation) in order to demonstrate that degradants from the vitamins, preservatives and/or product excipients do not interfere with the quantification of vitamins and preservatives. Typical validation characteristics: selectivity, accuracy, precision, linearity, range, limit of quantification and limit of detection were evaluated for vitamins and preservatives.

Lipid stability in meat and meat products.

PubMed

Morrissey, P A; Sheehy, P J; Galvin, K; Kerry, J P; Buckley, D J

1998-01-01

Lipid oxidation is one of the main factors limiting the quality and acceptability of meats and meat products. Oxidative damage to lipids occurs in the living animal because of an imbalance between the production of reactive oxygen species and the animal's defence mechanisms. This may be brought about by a high intake of oxidized lipids or poly-unsaturated fatty acids, or a low intake of nutrients involved in the antioxidant defence system. Damage to lipids may be accentuated in the immediate post-slaughter period and, in particular, during handling, processing, storage and cooking. In recent years, pressure to reduce artificial additive use in foods has led to attempts to increase meat stability by dietary strategies. These include supplementation of animal diets with vitamin E, ascorbic acid, or carotenoids, or withdrawal of trace mineral supplements. Dietary vitamin E supplementation reduces lipid and myoglobin oxidation, and, in certain situations, drip losses in meats. However, vitamin C supplementation appears to have little, if any, beneficial effects on meat stability. The effect of feeding higher levels of carotenoids on meat stability requires further study. Some studies have demonstrated that reducing the iron and copper content of feeds improves meat stability. Post-slaughter carnosine addition may be an effective means of improving lipid stability in processed meats, perhaps in combination with dietary vitamin E supplementation.

Osmotic dehydration effects on major and minor components of chestnut (Castanea sativa Mill.) slices.

PubMed

Delgado, Teresa; Pereira, José Alberto; Ramalhosa, Elsa; Casal, Susana

2017-08-01

The effect of osmotic dehydration (OD) conditions (temperature, time and sucrose concentration) on some nutritional parameters, soluble sugars, organic acids, fatty acids and vitamin E composition of chestnut slices was studied. Temperature at 60 °C and contact time of 7.5 h decreased significantly both protein (in 20 and 15%) and fat (in 25 and 20%) contents when compared to 30 °C and contact time of 2.5 h, simultaneously with the incorporation of sugars from the osmotic medium. An increase in temperature from 30 to 60 °C and contact time from 2.5 to 7.5 h also changed amylose percentage from 12 to 17 g/100 g of starch, suggesting modifications on starch conformation. Concerning organic acids, an increase in temperature from 30 to 60 °C induced thermal degradation of citric (54% of loss), malic (36% of loss) and ascorbic (23% of loss) acids. Temperature and sugar concentration did not affect significantly fat composition, particularly PUFA, the main fatty acid class, while contact times of 7.5 h led to the partial oxidation of linolenic acid (17% of loss when compared to 2.5 h). A 50% decrease was also observed on vitamin E content when temperature increased from 30 to 60 °C. Thus, OD might cause changes on the chemical composition of chestnut slices, requiring low temperature and contact times to avoid loss of important bioactive components such as ω-3 fatty acids (ex. linolenic acid) and vitamin E.

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

Vitamin C deficiency exerts paradoxical cardiovascular effects in osteogenic disorder Shionogi (ODS) rats.

PubMed

Vergely, Catherine; Goirand, Françoise; Ecarnot-Laubriet, Aline; Renard, Céline; Moreau, Daniel; Guilland, Jean-Claude; Dumas, Monique; Rochette, Luc

2004-04-01

Vitamin C is considered to be a very efficient water-soluble antioxidant, for which several new cardiovascular properties were recently described. The aim of this study was to determine in vivo the effects of a severe depletion of vitamin C on cardiac and vascular variables and reperfusion arrhythmias. For this purpose, we used a mutant strain of Wistar rats, osteogenic disorder Shionogi (ODS). After 15 d of consuming a vitamin C-deficient diet, ODS rats had a 90% decrease in plasma and tissue levels of ascorbate compared with ODS vitamin C-supplemented rats and normal Wistar rats. However, plasma antioxidant capacity, proteins, alpha-tocopherol, urate, catecholamines, lipids, and nitrate were not influenced by the vitamin C deficiency in ODS rats. Moreover, there was no difference between ODS vitamin C-deficient and -supplemented rats in heart rate and arterial pressure. After 5 min of an in vivo regional myocardial ischemia, various severe arrhythmias were observed, but their intensities were not modified by vitamin C in vitamin C-deficient ODS rats. The vascular reactivity, measured in vitro on thoracic arteries, was not altered by ascorbate deficiency in ODS rats. These unexpected results suggest that unidentified compensatory mechanisms play a role in maintaining normal cardiac function and vascular reactivity in vitamin C-deficient rats.

Modulation of LXR-α and the effector genes by Ascorbic acid and Statins in psoriatic keratinocytes.

PubMed

Soodgupta, Deepti; Kaul, Deepak; Kanwar, A J; Parsad, Davinder

2014-12-01

Recent studies have revealed critical roles that nuclear receptors like LXR-α (Liver X Receptor- alpha) plays as a class of post-transcriptional gene regulator in skin development and diseases. Keeping in view the fact that LXR-α plays crucial role in keratinocyte proliferation and differentiation, it becomes imperative to dissect the pathways and role of LXR-α genomics in the pathogenesis of psoriasis with ultimate aim to explore novel preventive/therapeutic strategies as treatment options. To explore the effects of agonists and activators of LXR-α on its own gene expression and the putative targets in psoriatic keratinocytes. Identification of promoter sequences for (vitamin D receptor) VDR and Catalase were done using in silico analysis followed by β-galactosidase (β-gal) reporter plasmid assay in keratinocytes from clinically heathy subjects. Determination of relative levels of LXR-α,VDR and catalase in control versus treated cells upon activation of LXR-α with Atorvastatin + 22R hydroxycholestrol and Ascorbic acid + 22R hydroxycholestrol was done by PCR and Cell Proliferation Assay. The cells transfected with the reporter plasmid element for VDR and catalase showed more than 5 and 4 fold increase respectively in the β-gal activity compared to the control. An increase of 55% in LXR-α gene expression at RNA level was observed in Atorvastatin + 22-R hydroxycholestrol compared to 24% in Ascorbic acid + 22-ROH cholesterol. The expression of the VDR and Catalase was significantly increased in both treated keratinocytes compared to its normal counterpart.

Differential Regulation of the Ascorbic Acid Transporter SVCT2 during Development and in Response to Ascorbic Acid Depletion

PubMed Central

Meredith, M. Elizabeth; Harrison, Fiona E.; May, James M.

2011-01-01

The sodium-dependent vitamin C transporter-2 (SVCT2) is the only ascorbic acid (ASC) transporter significantly expressed in brain. It is required for life and critical during brain development to supply adequate levels of ASC. To assess SVCT2 function in the developing brain, we studied time-dependent SVCT2 mRNA and protein expression in mouse brain, using liver as a comparison tissue because it is the site of ASC synthesis. We found that SVCT2 expression followed an inverse relationship with ASC levels in the developing brain. In cortex and cerebellum, ASC levels were high throughout late embryonic stages and early post-natal stages and decreased with age, whereas SVCT2 mRNA and protein levels were low in embryos and increased with age. A different response was observed for liver, in which ASC levels and SVCT2 expression were both low throughout embryogenesis and increased post-natally. To determine whether low intracellular ASC might be capable of driving SVCT2 expression, we depleted ASC by diet in adult mice unable to synthesize ASC. We observed that SVCT2 mRNA and protein were not affected by ASC depletion in brain cortex, but SVCT2 protein expression was increased by ASC depletion in the cerebellum and liver. The results suggest that expression of the SVCT2 is differentially regulated during embryonic development and in adulthood. PMID:22001929

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.

Polymeric Systems for Amorphous Δ9-Tetrahydrocannabinol Produced by a Hot-Melt Method. Part II: Effect of Oxidation Mechanisms and Chemical Interactions on Stability

PubMed Central

MUNJAL, MANISH; ELSOHLY, MAHMOUD A.; REPKA, MICHAEL A.

2010-01-01

The objectives of the present research investigations were to (i) elucidate the mechanism for the oxidative degradation of Δ9-tetrahydrocannabinol (THC) in polymer matrix systems prepared by a hot-melt fabrication procedure, and (ii) study the potential for controlling these mechanisms to reduce the degradation of THC in solid dosage formulations. Various factors considered and applied included drug-excipient compatibility, use of antioxidants, cross-linking in polymeric matrices, microenvironment pH, and moisture effect. Instability of THC in polyethylene oxide (PEO)-vitamin E succinate (VES) patches was determined to be due to chemical interaction between the drug and the vitamin as well as with the atmospheric oxygen. Of the different classes and mechanisms of antioxidants studied, quenching of oxygen by reducing agents, namely, ascorbic acid was the most effective in stabilizing THC in PEO-VES matrices. Only 5.8% of the drug degraded in the ascorbic acid-containing patch as compared to the control (31.6%) after 2 months of storage at 40°C. This coupled with the cross-linking extent and adjustment of the pH microenvironment, which seemed to have an impact on the THC degradation, might be effectively utilized towards stabilization of the drug in these polymeric matrices and other pharmaceutical dosage forms. These studies are relevant to the development of a stable transmucosal matrix system for the therapeutic delivery of amorphous THC. PMID:16886199

alpha-Tocopheryl succinate promotes selective cell death induced by vitamin K3 in combination with ascorbate.

PubMed

Tomasetti, M; Strafella, E; Staffolani, S; Santarelli, L; Neuzil, J; Guerrieri, R

2010-04-13

A strategy to reduce the secondary effects of anti-cancer agents is to potentiate the therapeutic effect by their combination. A combination of vitamin K3 (VK3) and ascorbic acid (AA) exhibited an anti-cancer synergistic effect, associated with extracellular production of H(2)O(2) that promoted cell death. The redox-silent vitamin E analogue alpha-tocopheryl succinate (alpha-TOS) was used in combination with VK3 and AA to evaluate their effect on prostate cancer cells. Prostate cancer cells were sensitive to alpha-TOS and VK3 treatment, but resistant to AA upto 3.2 mM. When combined, a synergistic effect was found for VK3-AA, whereas alpha-TOS-VK3 and alpha-TOS-AA combination showed an antagonist and additive effect, respectively. However, sub-lethal doses of AA-VK3 combination combined with a sub-toxic dose of alpha-TOS showed to induce efficient cell death that resembles autoschizis. Associated with this cell demise, lipid peroxidation, DNA damage, cytoskeleton alteration, lysosomal-mitochondrial perturbation, and release of cytochrome c without caspase activation were observed. Inhibition of lysosomal proteases did not attenuate cell death induced by the combined agents. Furthermore, cell deaths by apoptosis and autoschizis were detected. These finding support the emerging idea that synergistic combinations of some agents can overcome toxicity and other side-effects associated with high doses of single drugs creating the opportunity for therapeutically relevant selectivity.

Sequestering ability of butylated hydroxytoluene, propyl gallate, resveratrol, and vitamins C and E against ABTS, DPPH, and hydroxyl free radicals in chemical and biological systems.

PubMed

Soares, Daniele G; Andreazza, Ana C; Salvador, Mirian

2003-02-12

The antioxidant capacity of butylated hydroxytoluene (BHT; 2,6-di-tert-butyl-p-cresol), propyl gallate (3,4,5-trihydroxybenzoic acid n-propyl ester), resveratrol (trans-3,4',5-trihydroxystilbene), and vitamins C (l-ascorbic acid) and E [(+)-alpha-tocopherol] was studied in chemical and biological systems. The chemical assays evaluated the capacity of these antioxidants to sequester 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS.) and 1,1 diphenyl-2-picrylhydrazyl (DPPH.). A new colorimetric method to determine hydroxyl radical scavenging is also described. The biological tests use the eucaryotic cells of Saccharomyces cerevisiae treated with the antioxidants in the presence of the stressing agents apomorphine, hydrogen peroxide, and paraquat dichloride (methylviologen; 1,1'-dimethyl-4,4'-bipyridinium dichloride). The results in chemical systems showed that all of the antioxidants were able to significantly inhibit the oxidation of beta-carotene by hydroxyl free radicals. The assays in yeast showed that the antioxidant activity of the tested compounds depended on the stressing agent used and the mechanism of action of the antioxidant.

Interaction between vitamins C and E affects their tissue concentrations, growth, lipid oxidation, and deficiency symptoms in yellow perch (Perca flavescens).

PubMed

Lee, Kyeong-Jun; Dabrowski, Konrad

2003-05-01

We have conducted studies with juvenile yellow perch (Perca flavescens) over a period of 20 weeks to address the question of the interaction between water- and lipid-soluble antioxidant vitamins. Fish (2.25+/-0.14 g) were divided into twelve groups, and triplicate groups were fed one of four casein-based, semi-purified diets formulated to contain low or high vitamin E levels of either 5 or 160 mg/kg without or with vitamin C supplementation (250 mg/kg). Diets were designated as -C-E, -C+E, +C-E, or +C+E, respectively. The fish fed the +C+E diet showed significantly higher weight gain, feed intake, and feed efficiency than the groups fed vitamin C-deficient diets. Total ascorbate concentrations of liver were significantly higher in fish fed vitamin C-supplemented diets than in fish fed the vitamin C-deficient diet after 16 and 20 weeks. The liver alpha-tocopherol concentrations were increased by supplemental vitamin C in vitamin E-deficient dietary groups which indicates a sparing or regenerating effect of vitamin C on vitamin E. Fish fed vitamin C-deficient diets (-C-E and -C+E) exhibited severe deficiency symptoms, such as scoliosis, lens cataracts, anorexia, and haemorrhages. The cumulative mortality was significantly higher in the -C-E groups. The thiobarbituric acid-reactive substances value was significantly higher in blood plasma of fish fed a diet unsupplemented with both vitamins. The findings in the present study with yellow perch support the hypothesis that vitamin C regenerates and/or spares vitamin E in vivo.

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

Double-blind, half-face study comparing topical vitamin C and vehicle for rejuvenation of photodamage.

PubMed

Fitzpatrick, Richard E; Rostan, Elizabeth F

2002-03-01

Aging of the population, in particular the "baby boomers," has resulted in increased interest in methods of reversal of photodamage. Non-invasive treatments are in high demand, and our knowledge of mechanisms of photodamage to skin, protection of the skin, and repair of photodamage are becoming more sophisticated and complex. The objective of this study is to determine if the topical use of a vitamin C preparation can stimulate the skin to repair photodamage and result in clinically visible differences, as well as microscopically visible improvement. Ten patients applied in a double-blind manner a newly formulated vitamin C complex having 10% ascorbic acid (water soluble) and 7% tetrahexyldecyl ascorbate (lipid soluble) in an anhydrous polysilicone gel base to one-half of the face and the inactive polysilicone gel base to the opposite side. Clincial evaluation of wrinkling, pigmentation, inflammation, and hydration was performed prior to the study and at weeks 4, 8, and 12. Two mm punch biopsies of the lateral cheeks were performed at 12 weeks in four patients and stained with hematoxylin and eosin, as well as in situ hybridization studies using an anti-sense probe for mRNA for type I collagen. A questionnaire was also completed by each patient. A statistically significant improvement of the vitamin C-treated side was seen in the decreased photoaging scores of the cheeks (P = 0.006) and the peri-oral area (P = 0.01). The peri-orbital area improved bilaterally, probably indicating improved hydration. The overall facial improvement of the vitamin C side was statistically significant (P = 0.01). Biopsies showed increased Grenz zone collagen, as well as increased staining for mRNA for type I collagen. No patients were found to have any evidence of inflammation. Hydration was improved bilaterally. Four patients felt that the vitamin C-treated side improved unilaterally. No patient felt the placebo side showed unilateral improvement. This formulation of vitamin C results in clinically visible and statistically significant improvement in wrinkling when used topically for 12 weeks. This clinical improvement correlates with biopsy evidence of new collagen formation.

Mitochondrion-Permeable Antioxidants to Treat ROS-Burst-Mediated Acute Diseases

PubMed Central

Zhang, Zhong-Wei; Xu, Xiao-Chao; Liu, Ting

2016-01-01

Reactive oxygen species (ROS) play a crucial role in the inflammatory response and cytokine outbreak, such as during virus infections, diabetes, cancer, cardiovascular diseases, and neurodegenerative diseases. Therefore, antioxidant is an important medicine to ROS-related diseases. For example, ascorbic acid (vitamin C, VC) was suggested as the candidate antioxidant to treat multiple diseases. However, long-term use of high-dose VC causes many side effects. In this review, we compare and analyze all kinds of mitochondrion-permeable antioxidants, including edaravone, idebenone, α-Lipoic acid, carotenoids, vitamin E, and coenzyme Q10, and mitochondria-targeted antioxidants MitoQ and SkQ and propose astaxanthin (a special carotenoid) to be the best antioxidant for ROS-burst-mediated acute diseases, like avian influenza infection and ischemia-reperfusion. Nevertheless, astaxanthins are so unstable that most of them are inactivated after oral administration. Therefore, astaxanthin injection is suggested hypothetically. The drawbacks of the antioxidants are also reviewed, which limit the use of antioxidants as coadjuvants in the treatment of ROS-associated disorders. PMID:26649144

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.

Vitamin C in Health and Disease: Its Role in the Metabolism of Cells and Redox State in the Brain.

PubMed

Figueroa-Méndez, Rodrigo; Rivas-Arancibia, Selva

2015-01-01

Ever since Linus Pauling published his studies, the effects of vitamin C have been surrounded by contradictory results. This may be because its effects depend on a number of factors such as the redox state of the body, the dose used, and also on the tissue metabolism. This review deals with vitamin C pharmacokinetics and its participation in neurophysiological processes, as well as its role in the maintenance of redox balance. The distribution and the concentration of vitamin C in the organs depend on the ascorbate requirements of each and on the tissue distribution of sodium-dependent vitamin C transporter 1 and 2 (SVCT1 and SVCT2). This determines the specific distribution pattern of vitamin C in the body. Vitamin C is involved in the physiology of the nervous system, including the support and the structure of the neurons, the processes of differentiation, maturation, and neuronal survival; the synthesis of catecholamine, and the modulation of neurotransmission. This antioxidant interacts with self-recycling mechanisms, including its participation in the endogenous antioxidant system. We conclude that the pharmacokinetic properties of ascorbate are related to the redox state and its functions and effects in tissues.

Vitamin C in Health and Disease: Its Role in the Metabolism of Cells and Redox State in the Brain

PubMed Central

Figueroa-Méndez, Rodrigo; Rivas-Arancibia, Selva

2015-01-01

Ever since Linus Pauling published his studies, the effects of vitamin C have been surrounded by contradictory results. This may be because its effects depend on a number of factors such as the redox state of the body, the dose used, and also on the tissue metabolism. This review deals with vitamin C pharmacokinetics and its participation in neurophysiological processes, as well as its role in the maintenance of redox balance. The distribution and the concentration of vitamin C in the organs depend on the ascorbate requirements of each and on the tissue distribution of sodium-dependent vitamin C transporter 1 and 2 (SVCT1 and SVCT2). This determines the specific distribution pattern of vitamin C in the body. Vitamin C is involved in the physiology of the nervous system, including the support and the structure of the neurons, the processes of differentiation, maturation, and neuronal survival; the synthesis of catecholamine, and the modulation of neurotransmission. This antioxidant interacts with self-recycling mechanisms, including its participation in the endogenous antioxidant system. We conclude that the pharmacokinetic properties of ascorbate are related to the redox state and its functions and effects in tissues. PMID:26779027

Synergistic protective role of mirazid (Commiphora molmol) and ascorbic acid against tilmicosin-induced cardiotoxicity in mice.

PubMed

Abdel-Daim, Mohamed M; Ghazy, Emad W; Fayez, Mostafa

2015-01-01

Tilmicosin (TIL) is a long-acting macrolide antibiotic approved for the treatment of cattle with Bovine Respiratory Disease. However, overdose of TIL has been reported to induce cardiotoxicity. The purpose of our experiment was to evaluate the protective effects of Commiphora molmol (mirazid (MRZ); myrrh) and (or) ascorbic acid (AA) against TIL-induced cardiotoxicity in mice. MRZ and AA were orally administered using stomach gavage, either alone or in combination for 5 consecutive days, followed with a single TIL overdose. TIL overdose induced a significant increase in serum levels of cardiac damage biomarkers (AST, LDH, CK, CK-MB, and cTnT), as well as cardiac lipid peroxidation, but cardiac levels of antioxidant biomarkers (GSH, SOD, CAT, and TAC) were decreased. Both MRZ and AA tended to normalize the elevated serum levels of cardiac injury biomarkers. Furthermore, MRZ and AA reduced TIL-induced lipid peroxidation and oxidative stress parameters. MRZ and AA combined produced a synergistic cardioprotective effect. We conclude that myrrh and (or) vitamin C administration minimizes the toxic effects of TIL through their free-radical-scavenging and potent antioxidant activities.

A novel voltammetric sensor for ascorbic acid based on molecularly imprinted poly(o-phenylenediamine-co-o-aminophenol).

PubMed

Kong, Yong; Shan, Xueling; Ma, Jianfeng; Chen, Meilan; Chen, Zhidong

2014-01-27

A molecularly imprinted copolymer, poly(o-phenylenediamine-co-o-aminophenol) (PoPDoAP), was prepared as a new ascorbic acid (AA) sensor. The copolymer was synthesized by incorporation of AA as template molecules during the electrochemical copolymerization of o-phenylenediamine and o-aminophenol, and complementary sites were formed after the copolymer was electrochemically reduced in ammonium aqueous solution. The molecularly imprinted copolymer sensor exhibited a high sensitivity and selectivity toward AA. Differential pulse voltammograms (DPVs) showed a linear concentration range of AA from 0.1 to 10 mM, and the detection limit was calculated to be 36.4 μM. Compared to conventional polyaniline-based AA sensors, the analytical performance of the imprinted copolymer sensor was improved due to the broadened usable pH range of PoPDoAP (from pH 1.0 to pH 8.0). The sensor also exhibited a good reproducibility and stability. And it has been successfully applied in the determination of AA in real samples, including vitamin C tablet and orange juices, with satisfactory results. Copyright © 2013 Elsevier B.V. All rights reserved.

[Effect of ascorbic acid (vitamin C) on the EPR spectra from the black and red hair].

PubMed

Chikvaidze, E; Miminoshvili, A; Gogoladze, T; Kiparoidze, S

2012-02-01

The EPR spectra of melanin's free radicals in natural black and red hair have been investigated. It is show that the EPR spectrum of black hair is slightly asymmetric singlet with g=2,0035 and ΔH=0,5 mTl. The EPR spectrum of red hair with g=2,0053 differs from the spectrum of black hair. Under the influence of visible (blue with λ(max)=450 nm) in both types of hair (black and red), the protoinduced free radicals appear, which indicates an increase in the intensity of already existing EPR spectrum of hair. It should be noted that the EPR spectra of red hair from various donors are different. The antioxidant ascorbic acid has the different effect on the photoinduced free radicals. In particular, in the case of black hair, the concentration of photoinduced free radicals is slightly reduced, whereas in red hair, the disappearance of the triplet in the spectrum is observed, and at the same time, the spectrum becomes a singlet, the intensity of which increases sharply.

Fast and simultaneous detection of prominent natural antioxidants using analytical microsystems for capillary electrophoresis with a glassy carbon electrode: a new gateway to food environments.

PubMed

Blasco, Antonio Javier; Barrigas, Inés; González, María Cristina; Escarpa, Alberto

2005-12-01

This paper examines for the first time the analytical possibilities of fast and simultaneous detection of prominent natural antioxidants including examples of flavonoids and vitamins using a CE microchip with electrochemical detection (ED). Unpinched injection conditions, zone electrophoretic separation and amperometric detection were carefully assayed and optimised. Analysis involved the zone electrophoretic separation of arbutin, (+)-catechin and ascorbic acid in less than 4 min using a borate buffer (pH 9.0, 50 mM), employing 2 kV as the separation voltage and +1.0 V as the detection potential. In addition, the separation of different 'couples' of natural antioxidants of food significance including (+)-catechin and ascorbic acid, (+)-catechin and rutin, as well as arbutin and phlorizdin is proposed. To demonstrate the potential and future role of CE microsystems, analytical possibilities and a new route in the raw sample analysis are presented. The preliminary results obtained allow the proposal of CE-ED microchips as a real gateway to microanalysis in foods.

Advances in diabetes for the millennium: vitamins and oxidant stress in diabetes and its complications.

PubMed

Chertow, Bruce

2004-11-01

Hyperinduced oxidant stress may have a role in the pathogenesis of diabetes and its micro- and macrovascular complications. Attaining euglycemia and the use of antioxidant vitamins could reduce oxidant stress and complications. In general, evidence does not support the use of supplements, and supplements are not recommended unless patients are deficient. Use of vitamins in excess may have adverse effects. Vitamin supplements are indicated in patients deficient in vitamins due to inadequate dietary intake or intestinal disease. Treatment with proper amounts of vitamins and antioxidants is best accomplished with a balanced diet including 3 servings of vegetables and 2 servings of fruits. Regarding supplementation of specific vitamins: carotene cannot be recommended in view of the possible harm and lack of benefit in clinical studies. Vitamin A (retinol) and Vitamin D should be repleted if deficient by laboratory assay. Excesses should be avoided. Vitamin A supplements, particularly in pregnancy, should not exceed 10,000 IU daily or a supplement should not exceed 25,000 units weekly. Vitamin E (alpha-tocopherol) alone in doses of 400 units is of questionable value, and larger doses may cause intracranial hemorrhage or interact negatively with lipid-lowering drugs. Vitamin E should not be used in patients who have bleeding disorders or patients on anticoagulants or acetylsalicylic acid (ASA). Vitamin C (ascorbic acid) losses in urine may be excessive in diabetic patients and may require repletion to 200 mg in nonsmokers and 250 mg in smokers. Further studies are needed testing: (1) vitamin supplementation in subgroups of patients at high risk for specific complications using tissue-specific indicators of oxidative stress; (2) the role of oxidative stress in nephropathy, diabetic myocardiopathy, dermopathy, joint limitation syndromes, peripheral edema, metabolic bone disease, and pregnancy; (3) the impact of renal failure on oxidative stress; and (4) the effects of diabetes and dietary vitamins on the relative amounts of retinoids, carotenoids, and vitamin E in the chylomicron and lipoproteins, and how this affects assimilation, oxidation of lipids, and atherosclerotic plaque formation.

Advances in Diabetes for the Millennium: Vitamins and Oxidant Stress in Diabetes and Its Complications

PubMed Central

Chertow, Bruce

2004-01-01

Hyperinduced oxidant stress may have a role in the pathogenesis of diabetes and its micro- and macrovascular complications. Attaining euglycemia and the use of antioxidant vitamins could reduce oxidant stress and complications. In general, evidence does not support the use of supplements, and supplements are not recommended unless patients are deficient. Use of vitamins in excess may have adverse effects. Vitamin supplements are indicated in patients deficient in vitamins due to inadequate dietary intake or intestinal disease. Treatment with proper amounts of vitamins and antioxidants is best accomplished with a balanced diet including 3 servings of vegetables and 2 servings of fruits. Regarding supplementation of specific vitamins: carotene cannot be recommended in view of the possible harm and lack of benefit in clinical studies. Vitamin A (retinol) and Vitamin D should be repleted if deficient by laboratory assay. Excesses should be avoided. Vitamin A supplements, particularly in pregnancy, should not exceed 10,000 IU daily or a supplement should not exceed 25,000 units weekly. Vitamin E (alpha-tocopherol) alone in doses of 400 units is of questionable value, and larger doses may cause intracranial hemorrhage or interact negatively with lipid-lowering drugs. Vitamin E should not be used in patients who have bleeding disorders or patients on anticoagulants or acetylsalicylic acid (ASA). Vitamin C (ascorbic acid) losses in urine may be excessive in diabetic patients and may require repletion to 200 mg in nonsmokers and 250 mg in smokers. Further studies are needed testing: (1) vitamin supplementation in subgroups of patients at high risk for specific complications using tissue-specific indicators of oxidative stress; (2) the role of oxidative stress in nephropathy, diabetic myocardiopathy, dermopathy, joint limitation syndromes, peripheral edema, metabolic bone disease, and pregnancy; (3) the impact of renal failure on oxidative stress; and (4) the effects of diabetes and dietary vitamins on the relative amounts of retinoids, carotenoids, and vitamin E in the chylomicron and lipoproteins, and how this affects assimilation, oxidation of lipids, and atherosclerotic plaque formation. PMID:15647709

Effect of vitamin C on innate immune responses of rainbow trout (Oncorhynchus mykiss) leukocytes.

PubMed

Leal, Esther; Zarza, Carlos; Tafalla, Carolina

2017-08-01

Vitamin C, also known as ascorbic acid, is an essential micronutrient that influences a wide variety of physiological processes, including immunological functions. Although the positive effects of vitamin C supplementation on the immunological status of fish has been established in different species, the bases for these positive effects are still unknown. Hence, the aim of our study was to evaluate the in vitro effect of vitamin C on several innate immune functions of rainbow trout (Oncorhynchus mykiss) leukocyte populations. For this, we assessed the effects exerted on the established rainbow trout monocyte-macrophage cell line RTS11, and compared them to those observed in trout head kidney leukocytes. Our results demonstrate that vitamin C increases the production of reactive oxygen species and the percentage of phagocytic cells in both cell populations. On the other hand, vitamin C had no effect on the surface MHC II levels and only in the case of RTS11 cells increased the capacity of these cells to migrate towards the CK9 chemokine. Finally, vitamin C also increased the transcription of several pro-inflammatory and antimicrobial genes elicited by Escherichia coli, with some differences depending on the cell population studied. Our results contribute to further understand how vitamin C supplementation regulates the fish immune system. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

A critical review of vitamin C for the prevention of age-related cognitive decline and Alzheimer's disease.

PubMed

Harrison, Fiona E

2012-01-01

Antioxidants in the diet have long been thought to confer some level of protection against the oxidative damage that is involved in the pathology of Alzheimer's disease as well as general cognitive decline in normal aging. Nevertheless, support for this hypothesis in the literature is equivocal. In the case of vitamin C (ascorbic acid) in particular, lack of consideration of some of the specific features of vitamin C metabolism has led to studies in which classification of participants according to vitamin C status is inaccurate, and the absence of critical information precludes the drawing of appropriate conclusions. Vitamin C levels in plasma are not always reported, and estimated daily intake from food diaries may not be accurate or reflect actual plasma values. The ability to transport ingested vitamin C from the intestines into blood is limited by the saturable sodium-dependent vitamin C transporter (SVCT1) and thus very high intakes and the use of supplements are often erroneously considered to be of greater benefit that they really are. The current review documents differences among the studies in terms of vitamin C status of participants. Overall, there is a large body of evidence that maintaining healthy vitamin C levels can have a protective function against age-related cognitive decline and Alzheimer's disease, but avoiding vitamin C deficiency is likely to be more beneficial than taking supplements on top of a normal, healthy diet.

A novel multi-tiered experimental approach unfolding the mechanisms behind cyclodextrin-vitamin inclusion complexes for enhanced vitamin solubility and stability.

PubMed

Braithwaite, Miles C; Kumar, Pradeep; Choonara, Yahya E; du Toit, Lisa C; Tomar, Lomas K; Tyagi, Charu; Pillay, Viness

2017-10-30

This study was conducted to provide a mechanistic account for understanding the synthesis, characterization and solubility phenomena of vitamin complexes with cyclodextrins (CD) for enhanced solubility and stability employing experimental and in silico molecular modeling strategies. New geometric, molecular and energetic analyses were pursued to explicate experimentally derived cholecalciferol complexes. Various CD molecules (α-, β-, γ-, and hydroxypropyl β-) were complexed with three vitamins: cholecalciferol, ascorbic acid and α-tocopherol. The Inclusion Efficiency (IE%) was computed for each CD-vitamin complex. The highest IE% achieved for a cholecalciferol complex was for 'βCDD 3 -8', after utilizing a unique CD:cholecalciferol molar synthesis ratio of 2.5:1, never before reported as successful. 2HPβCD-cholecalciferol, γCD-cholecalciferol and α-tocopherol inclusion complexes (IC's) reached maximal IE% with a CD:vitamin molar ratio of 5:1. The results demonstrate that IE%, thermal stability, concentration, carrier solubility, molecular mechanics and intended release profile are key factors to consider when synthesizing vitamin-CD complexes. Phase-solubility data provided insights into the design of formulations with IC's that may provide analogous oral vitamin release profiles even when hydrophobic and hydrophilic vitamins are co-incorporated. Static lattice atomistic simulations were able to validate experimentally derived cholecalciferol IE phenomena and are invaluable parameters when approaching formulation strategies using CD's for improved solubility and efficacy of vitamins. Copyright © 2017 Elsevier B.V. All rights reserved.

Blood vitamin concentrations in privately owned dogs fed non-standardized commercial diets and after intake of diets with specified vitamin concentrations.

PubMed

Tran, J L; Horvath, C; Krammer, S; Höller, U; Zentek, J

2007-02-01

The objective was to investigate in a survey study the blood vitamin concentrations in healthy dogs fed non-specified commercial complete diets and in an intervention study to determine the effects of defined dietary vitamin intakes on blood vitamin levels and hair and skin condition. Sixty-four privately owned dogs, aged from 1 to 8 years, without history of skin or coat problems were included. All animals were fed commercial complete diets with uncertain vitamin concentrations before enrolment. The animals were assigned, according to weight and gender, to four groups with graded vitamin intakes. The blood vitamin levels and skin and coat quality of the dogs were investigated at days 0 and day 122. Coat and hair condition was not influenced by the experimental diets. The retinol concentrations were reduced at the end of the experiment compared with the baseline levels, retinyl esters were not influenced. 25-Hydroxycholecalciferol decreased in all groups, alpha-tocopherol was constant or tended to decrease. Ascorbic acid, thiamine pyrophosphate and riboflavin concentrations were not affected by treatment, flavin adenine dinucleotide and pyridoxal-5'-phosphate were partially reduced on day 122. Cobalamin, pantothenate and biotin concentrations increased with higher dietary intakes, folate levels in tendency. In conclusion, this study gives a survey of blood vitamin concentrations in healthy dogs and provides a data base for the evaluation of the vitamin status in health and disease.

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.

The prophylactic effect of vitamin C on oxidative stress indexes in rat eyes following exposure to radiofrequency wave generated by a BTS antenna model.

PubMed

Jelodar, Gholamali; Akbari, Abolfazl; Nazifi, Saeed

2013-02-01

This study was conducted to evaluate the effect of radiofrequency wave (RFW)-induced oxidative stress in the eye and the prophylactic effect of vitamin C on this organ by measuring the antioxidant enzymes activity including: glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT), and malondialdehyde (MDA). Thirty-two adult male Sprague-Dawley rats were randomly divided into four experimental groups and treated daily for 45 days as follows: Control, vitamin C (L-ascorbic acid 200 mg/kg of body weight/day by gavage), test (exposed to 900 MHz RFW) and the treated group (received vitamin C in addition to exposure to RFW). At the end of the experiment all animals were sacrificed, their eyes were removed and were used for measurement of antioxidant enzymes and MDA activity. The results indicate that exposure to RFW in the test group decreased antioxidant enzymes activity and increased MDA compared with the control groups (P < 0.05). In the treated group vitamin C improved antioxidant enzymes activity and reduced MDA compared to the test group (P < 0.05). It can be concluded that RFW causes oxidative stress in the eyes and vitamin C improves the antioxidant enzymes activity and decreases MDA.

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...

Response of nutrients, minerals, antioxidant leaf pigments, vitamins, polyphenol, flavonoid and antioxidant activity in selected vegetable amaranth under four soil water content.

PubMed

Sarker, Umakanta; Oba, Shinya

2018-06-30

Four selected vegetable amaranths were grown under four soil water content to evaluate their response in nutrients, minerals, antioxidant leaf pigments, vitamins, polyphenol, flavonoid and total antioxidant activity (TAC). Vegetable amaranth was significantly affected by variety, soil water content and variety × soil water content interactions for all the traits studied. Increase in water stress, resulted in significant changes in proximate compositions, minerals (macro and micro), leaf pigments, vitamin, total polyphenol content (TPC), and total flavonoid content (TFC) of vegetable amaranth. Accessions VA14 and VA16 performed better for all the traits studied. Correlation study revealed a strong antioxidant scavenging activity of leaf pigments, ascorbic acid, TPC and TFC. Vegetable amaranth can tolerate soil water stress without compromising the high quality of the final product in terms of nutrients and antioxidant profiles. Therefore, it could be a promising alternative crop in semi-arid and dry areas and also during dry seasons. Copyright © 2018. Published by Elsevier Ltd.

Effects of ultraviolet light (UV-C) and heat treatment on the quality of fresh-cut Chokanan mango and Josephine pineapple.

PubMed

George, Dominic Soloman; Razali, Zuliana; Santhirasegaram, Vicknesha; Somasundram, Chandran

2015-02-01

The effects of ultraviolet (UV-C) and medium heat (70 °C) treatments on the quality of fresh-cut Chokanan mango and Josephine pineapple were investigated. Quality attributes included physicochemical properties (pH, titratable acidity, and total soluble solids), ascorbic acid content (vitamin C), antioxidant activity, as well as microbial inactivation. Consumers' acceptance was also investigated through sensory evaluation of the attributes (appearance, texture, aroma and taste). Furthermore, shelf-life study of samples stored at 4 ± 1 °C was conducted for 15 d. The fresh-cut fruits were exposed to UV-C for 0, 15, 30, and 60 min while heat treatments were carried out at 70 °C for 0, 5, 10 and 20 min. Both UV-C and medium heat treatments resulted in no significant changes to the physicochemical attributes of both fruits. The ascorbic acid content of UV-C treated fruits was unaffected; however, medium heat treatment resulted in deterioration of ascorbic acids in both fruits. The antioxidants were enhanced with UV-C treatment which could prove invaluable to consumers. Heat treatments on the other hand resulted in decreased antioxidant activities. Microbial count in both fruits was significantly reduced by both treatments. The shelf life of the fresh-cut fruits were also successfully extended to a maximum of 15 d following treatments. As for consumers' acceptance, UV-C treated fruits were the most accepted as compared to their heat-treated counterparts. The results obtained through this study support the use of UV-C treatment for better retention of quality, effective microbial inactivation and enhancement of health promoting compounds for the benefit of consumers. © 2015 Institute of Food Technologists®

Effects of blanching, acidification, or addition of EDTA on vitamin C and β-carotene stability during mango purée preparation.

PubMed

Guiamba, Isabel R F; Svanberg, Ulf

2016-09-01

The impact of acidification with citric acid, addition of EDTA or water blanching at high temperature, and short time (HTST) conducted at 90°C for 4 min, on the retention of vitamin C (L-AA and DHAA) and β-carotene was studied in mango purée 30 min after crushing. HTST blanching prior to matrix disruption into purée resulted in complete inactivation of polyphenol oxidase (PPO) and minor residual activity (8%) of ascorbic acid oxidase (AAO). The retention of total vitamin C was 100% in blanched purées and in purée with EDTA and about 90% in purées at pH 3.9 and 5.0. Acidification, blanching, and addition of EDTA preserved vitamin C mainly as L-AA, while complete conversion into DHAA was observed in purée at pH 5.0. The retention of all-trans-β-carotene was between 65 and 72%, with the highest value in purée with EDTA and the lowest value in purée of blanched mango. The ratio of 13-cis-β-carotene in fresh mango was 8.2 ± 0.5% that increased significantly after blanching and in purée at pH 5.0.

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. Topical 10% ascorbic acid has been claimed to reduce significantly the healing time of experimentally induced chrome ulcers in guinea pigs. The proposed mechanism is reduction on the skin surface of chromium(VI) to chromium(III). Several case reports suggest that topical ascorbic acid is effective in the management of chromium dermatitis but this has not been confirmed in controlled clinical trials and, moreover, the practical difficulties of frequent application are likely to limit its usefulness. Based on experimental studies, substantial amounts of ascorbic acid would need to be administered, preferably parenterally, soon after exposure to prevent systemic toxicity from chromium(VI) in humans. However, as ascorbic acid is a metabolic precursor of oxalate, the administration of ascorbic acid in high dose could lead to acute oxalate nephropathy, particularly in the presence of renal failure. While smaller doses of ascorbic acid (e.g., 10 g intravenously) are not toxic, such doses probably will not reduce the mortality from systemic chromium poisoning. There is currently insufficient evidence to advocate the use of ascorbic acid in the management of systemic chromium toxicity. Topical ascorbic acid may reduce dermal hexavalent chromium exposure, but this observation must be confirmed in controlled studies.

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...

Effects of Oral Vitamin C Supplementation on Anxiety in Students: A Double-Blind, Randomized, Placebo-Controlled Trial.

PubMed

de Oliveira, Ivaldo Jesus Lima; de Souza, Victor Vasconcelos; Motta, Vitor; Da-Silva, Sérgio Leme

2015-01-01

Vitamin C ascorbic acid) is a well-known antioxidant that is involved in anxiety, stress, depression, fatigue and mood state in humans. Studies have suggested that oxidative stress may trigger neuropsychological disorders. Antioxidants may play an important therapeutic role in combating the damage caused by oxidative stress in individuals that suffer from anxiety. In this context, it was hypothesized that oral vitamin C supplementation would reduce anxiety. However, few up to date studies have evaluated the consequences of oral vitamin C supplementation on anxiety in humans. The present study examined the effects of oral vitamin C supplements in 42 high school students, in a randomized, double-blind, placebo-controlled trial. The students were given either vitamin C (500 mg day(-1)) or placebo. Plasma concentrations of vitamin C and blood pressure were measured before the intervention and then one day after the intervention. Anxiety levels were evaluated for each student before and after 14 days following supplementation with the Beck Anxiety Inventory. Results showed that vitamin C reduced anxiety levels and led to higher plasma vitamin C concentration compared to the placebo. The mean heart rates were also significantly different between vitamin C group and placebo control group. Present study results not only provide evidence that vitamin C plays an important therapeutic role for anxiety but also point a possible use for antioxidants in the prevention or reduction of anxiety. This suggests that a diet rich in vitamin C may be an effective adjunct to medical and psychological treatment of anxiety and improve academic performance.

A Rapid and Specific Microplate Assay for the Determination of Intra- and Extracellular Ascorbate in Cultured Cells

PubMed Central

Lane, Darius J. R.; Lawen, Alfons

2014-01-01

Vitamin C (ascorbate) plays numerous important roles in cellular metabolism, many of which have only come to light in recent years. For instance, within the brain, ascorbate acts in a neuroprotective and neuromodulatory manner that involves ascorbate cycling between neurons and vicinal astrocytes - a relationship that appears to be crucial for brain ascorbate homeostasis. Additionally, emerging evidence strongly suggests that ascorbate has a greatly expanded role in regulating cellular and systemic iron metabolism than is classically recognized. The increasing recognition of the integral role of ascorbate in normal and deregulated cellular and organismal physiology demands a range of medium-throughput and high-sensitivity analytic techniques that can be executed without the need for highly expensive specialist equipment. Here we provide explicit instructions for a medium-throughput, specific and relatively inexpensive microplate assay for the determination of both intra- and extracellular ascorbate in cell culture. PMID:24747535

Vitamin C: electron emission, free radicals and biological versatility.

PubMed

Getoff, Nikola

2013-01-01

The many-sided biological role of vitamin C (ascorbate) is briefly illustrated by specific examples. It is demonstrated that in aqueous solutions, vitamin C emits solvated electrons (e(aq)(-)), when excited in single state. Vitamin C can also react with e(aq)(-) as well as transfer them to other biological systems and thereby acts as efficient electron mediator. Based on its chemical and biological properties, it is clear that vitamin C plays a very important role in various functions in the organism alongside biochemical processes.

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.

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.

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.

Nutritional composition and vitamin C stability in stored camu-camu (Myrciaria dubia) pulp.

PubMed

Justi, K C; Visentainer, J V; Evelázio de Souza, N; Matsushita, M

2000-12-01

Camu-camu (Myrciaria dubia), a native fruit of the Amazon region, is one of the richest sources of vitamin C (2.4 to 3.0 g/100 g in the pulp) found in Brazil. The purpose of this work was the physical-chemical characterization of some nutrients and the valuation of vitamin C stability in stored camu-camu pulp, produced by the Agronomic Institute of Paraná (IAPAR), Paraná State, Brazil. The vitamin C determination was made by titration with potassium iodate. The fruit produced in Paraná State, presented a lower content of vitamin C than the one native of the amazon region, possibly due to the different development conditions of the plant, and consequently of the fruit, as well as the climatic variation, the humidity and the characteristics of the soil. Regarding the vitamin C stability in stored (-18 degrees C) camu-camu pulp, a considerable decrease in its concentration until the 28th day was observed lost 23% (from 1.57 to 1.21 g/100 g), staying approximately the same until the end of the experiment. After 335 days of storage, the content found was of approximately 1.16 g/100 g of pulp, the ascorbic acid losses amounted to 26%. This content was still higher than the one found for most fruits that are good sources of this vitamin.

SVCT2 vitamin C transporter expression in progenitor cells of the postnatal neurogenic niche

PubMed Central

Pastor, Patricia; Cisternas, Pedro; Salazar, Katterine; Silva-Alvarez, Carmen; Oyarce, Karina; Jara, Nery; Espinoza, Francisca; Martínez, Agustín D.; Nualart, Francisco

2013-01-01

Known as a critical antioxidant, recent studies suggest that vitamin C plays an important role in stem cell generation, proliferation and differentiation. Vitamin C also enhances neural differentiation during cerebral development, a function that has not been studied in brain precursor cells. We observed that the rat neurogenic niche is structurally organized at day 15 of postnatal development, and proliferation and neural differentiation increase at day 21. In the human brain, a similar subventricular niche was observed at 1-month of postnatal development. Using immunohistochemistry, sodium-vitamin C cotransporter 2 (SVCT2) expression was detected in the subventricular zone (SVZ) and rostral migratory stream (RMS). Low co-distribution of SVCT2 and βIII-tubulin in neuroblasts or type-A cells was detected, and minimal co-localization of SVCT2 and GFAP in type-B or precursor cells was observed. Similar results were obtained in the human neurogenic niche. However, BrdU-positive cells also expressed SVCT2, suggesting a role of vitamin C in neural progenitor proliferation. Primary neurospheres prepared from rat brain and the P19 teratocarcinoma cell line, which forms neurospheres in vitro, were used to analyze the effect of vitamin C in neural stem cells. Both cell types expressed functional SVCT2 in vitro, and ascorbic acid (AA) induced their neural differentiation, increased βIII-tubulin and SVCT2 expression, and amplified vitamin C uptake. PMID:23964197

Assessing foliar ascorbate content in the rice diversity panel 1

USDA-ARS?s Scientific Manuscript database

Early spring plantings of rice can have poor stands due to cold temperatures. Our previous studies have shown that high vitamin C (ascorbate AsA) Arabidopsis lines are tolerant to cold stress. The rice diversity panel 1 (RDP1) represents the genetic diversity of Oryza sativa and has been extensively...

Vitamin C, total phenolics and antioxidative activity in tip-cut green beans (Phaseolus vulgaris) and swede rods (Brassica napus var. napobrassica) processed by methods used in catering.

PubMed

Baardseth, Pernille; Bjerke, Frøydis; Martinsen, Berit K; Skrede, Grete

2010-05-01

Retention of nutrients in vegetables during blanching/freezing, cooking and warm-holding is crucial in the preparation of both standard and therapeutic diets. In the present study, conventional cooking in water, and cooking by pouch technology (boil-in-bag, sous vide) were compared in their ability to retain vitamin C, total phenolics and antioxidative activity (DPPH and FRAP) in industrially blanched/frozen tip-cut green beans and swede rods. After conventional cooking, 50.4% total ascorbic acid, 76.7% total phenolics, 55.7% DPPH and 59.0% FRAP were recovered in the drained beans. After boil-in-bag cooking, significantly (P < 0.05) higher recoveries were obtained, i.e. 80.5% total ascorbic acid, 89.2% total phenolics, 94.8% DPPH and 92.9% FRAP. Recoveries after sous vide cooking were comparable to those of boil-in-bag cooking. By conventional cooking, 13.5-42.8% of the nutrients leaked into the cooking water; by sous vide about 10% leaked to the exuded liquid, while no leakage occurred by boil-in-bag cooking. Warm-holding beans after cooking reduced recoveries in all components. Recoveries in swede rods were comparable but overall slightly lower. Industrially blanched/frozen vegetables should preferably be cooked by pouch technology, rather than conventional cooking in water. Including cooking water or exuded liquid into the final dish will increase the level of nutrients in a meal. Warm-holding of vegetables after cooking should be avoided.

Cardioactive and vasoactive effects of natural wild honey against cardiac malperformance induced by hyperadrenergic activity.

PubMed

Rakha, Miran K; Nabil, Zohour I; Hussein, Aida A

2008-03-01

Induction of hyperadrenergic activity was experimentally achieved in urethane-anesthetized rats using epinephrine (adrenaline). Acute administration of epinephrine (100 microg/kg) for 2 hours induced several cardiac disorders and vasomotor dysfunction. Pretreatment with natural wild honey (5 g/kg) for 1 hour prior to the injection with epinephrine (100 mug/kg) protected the anesthetized normal rats from the incidence of epinephrine-induced cardiac disorders and vasomotor dysfunction. Moreover, posttreatment with natural wild honey (5 g/kg) following the injection with epinephrine (100 microg/kg) for 1 hour showed several ameliorative outcomes to the electrocardiographic parameters and vasomotor dysfunction of anesthetized stressed rats. Furthermore, natural wild honey preserved the positive inotropic effect of epinephrine in both cases. Also, the total antioxidant capacity (AOC) of natural wild honey was found to be very pronounced. Levels of both reduced glutathione and ascorbic acid (vitamin C) were considered relatively high in natural wild honey. Activity of superoxide dismutase (SOD) was also high, whereas catalase activity was relatively low, especially when compared to the value of SOD activity. It would appear from the results of the present study that natural wild honey may exert its cardioprotective and therapeutic effects against epinephrine-induced cardiac disorders and vasomotor dysfunction directly, via its very pronounced total AOC and its great wealth of both enzymatic and nonenzymatic antioxidants involved in cardiovascular defense mechanisms, besides its substantial quantities of mineral elements such as magnesium, sodium, and chlorine, and/or indirectly, via the enhancement of the endothelium-derived relaxing factor nitric oxide release through the influence of ascorbic acid (vitamin C).

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.

ESR study of a biological assay on whole blood: antioxidant efficiency of various vitamins.

PubMed

Stocker, Pierre; Lesgards, Jean-François; Vidal, Nicolas; Chalier, Florence; Prost, Michel

2003-04-07

This study deals with the activity of various vitamins against the radical-mediated oxidative damage in human whole blood. We have used a biological method that allows both the evaluation of plasma and that of red blood cell resistance against the free radicals induced by 2,2'-azobis (2-amidinopropane) hydrochloride (AAPH). Spin trapping measures using mainly 5-(diethoxyphosphoryl)-5-methyl-1-pyrolline N-oxide nitrone (DEPMPO) were carried out under several conditions to identify the free radicals implicated in this test. Only the oxygenated-centred radical generated from AAPH was found highly reactive to initiate red blood cell lysis. With DEPMPO only alkoxyl radicals were observed and no evidence was found for alkylperoxyl radicals. The antioxidant activity of several lipid- and water-soluble vitamins has been assessed by the biological assay and through two chemical methods. We have noticed high antioxidant activities for tocopherols (in the order delta>gamma>alpha) in the biological test but not through chemical methods. At 1 microM, the delta-tocopherol efficiency in inhibiting radical-induced red blood cell hemolysis was three times as high as the alpha-tocopherol efficiency. For beta-carotene no significant activity even in whole blood was shown. Highly surprising antioxidant activities were observed for acid folic and pyridoxine, compared to ascorbic acid. At 10 microM, the effectiveness of folic acid was almost three times as high as vitamin C. The biological test seems clinically more relevant than most other common assays because it can detect several classes of antioxidants.

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 supplementation may offer protection against heat-stress-related depression in performance of Japanese quails.

Dietary intake of the water-soluble vitamins B1, B2, B6, B12 and C in 10 countries in the European Prospective Investigation into Cancer and Nutrition.

PubMed

Olsen, A; Halkjaer, J; van Gils, C H; Buijsse, B; Verhagen, H; Jenab, M; Boutron-Ruault, M C; Ericson, U; Ocké, M C; Peeters, P H M; Touvier, M; Niravong, M; Waaseth, M; Skeie, G; Khaw, K T; Travis, R; Ferrari, P; Sanchez, M J; Agudo, A; Overvad, K; Linseisen, J; Weikert, C; Sacerdote, C; Evangelista, A; Zylis, D; Tsiotas, K; Manjer, J; van Guelpen, B; Riboli, E; Slimani, N; Bingham, S

2009-11-01

To describe the intake of vitamins thiamine (B1), riboflavin (B2), B6 (pyridoxine), B12 (cobalamine) and C (ascorbic acid) and their food sources among 27 centres in 10 countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Between 1995 and 2000, 36 034 persons aged between 35 and 74 years were administered a standardized 24-h dietary recall using a computerized interview software programme (EPIC-SOFT). Intakes of the four B vitamins and vitamin C were estimated using the standardized EPIC Nutrient Database (ENDB). Mean intakes were adjusted for age and weighted by season and day of recall. Intake of B vitamins did not vary considerably between centres, except in the UK health-conscious cohort, in which substantially higher intakes of thiamine and lower intakes of vitamin B12 were reported compared with other centres. Overall, meat was the most important contributor to the B vitamins in all centres except in the UK health-conscious group. Vitamin C showed a clear geographical gradient, with higher intakes in the southern centres as compared with the northern ones; this was more pronounced in men than in women. Vegetables and fruits were major contributors to vitamin C in all centres, but juices and potatoes were also important sources in the northern centres. This study showed no major differences across centres in the mean intakes of B vitamins (thiamine, riboflavin, B6, B12), whereas a tendency towards a north-south gradient was observed for vitamin C.

Attenuation of abnormalities in the lipid metabolism during experimental myocardial infarction induced by isoproterenol in rats: beneficial effect of ferulic acid and ascorbic acid.

PubMed

Yogeeta, Surinder Kumar; Hanumantra, Rao Balaji Raghavendran; Gnanapragasam, Arunachalam; Senthilkumar, Subramanian; Subhashini, Rajakannu; Devaki, Thiruvengadam

2006-05-01

The present study aims at evaluating the effect of the combination of ferulic acid and ascorbic acid on isoproterenol-induced abnormalities in lipid metabolism. The rats were divided into eight groups: Control, isoproterenol, ferulic acid alone, ascorbic acid alone, ferulic acid+ascorbic acid, ferulic acid+isoproterenol, ascorbic acid+isoproterenol and ferulic acid+ascorbic acid+isoproterenol. Ferulic acid (20 mg/kg b.w.t.) and ascorbic acid (80 mg/kg b.w.t.) both alone and in combination was administered orally for 6 days and on the fifth and the sixth day, isoproterenol (150 mg/kg b.w.t.) was injected intraperitoneally to induce myocardial injury to rats. Induction of rats with isoproterenol resulted in a significant increase in the levels of triglycerides, total cholesterol, free fatty acids, free and ester cholesterol in both serum and cardiac tissue. A rise in the levels of phospholipids, lipid peroxides, low density lipoprotein and very low density lipoprotein-cholesterol was also observed in the serum of isoproterenol-intoxicated rats. Further, a decrease in the level of high density lipoprotein in serum and in the phospholipid levels, in the heart of isoproterenol-intoxicated rats was observed, which was paralleled by abnormal activities of lipid metabolizing enzymes: total lipase, cholesterol ester synthase, lipoprotein lipase and lecithin: cholesterol acyl transferase. Pre-cotreatment with the combination of ferulic acid and ascorbic acid significantly attenuated these alterations and restored the levels to near normal when compared to individual treatment groups. Histopathological observations were also in correlation with the biochemical parameters. These findings indicate the synergistic protective effect of ferulic acid and ascorbic acid on isoproterenol-induced abnormalities in lipid metabolism.

Modified Folin-Ciocalteu antioxidant capacity assay for measuring lipophilic antioxidants.

PubMed

Berker, Kadriye Isil; Ozdemir Olgun, F Ayca; Ozyurt, Dilek; Demirata, Birsen; Apak, Resat

2013-05-22

The Folin-Ciocalteu (FC) method of performing a total phenolics assay, originally developed for protein determination, has recently evolved as a total antioxidant capacity assay but was found to be incapable of measuring lipophilic antioxidants due to the high affinity of the FC chromophore, that is, multivalent-charged phospho-tungsto-molybdate(V), toward water. Thus, the FC method was modified and standardized so as to enable simultaneous measurement of lipophilic and hydrophilic antioxidants in NaOH-added isobutanol-water medium. Optimal conditions were as follows: dilution ratio of aqueous FC reagent with iso-BuOH (1:2, v/v), final NaOH concentration of 3.5 × 10(-2) M, reaction time of 20 min, and maximum absorption wavelength of 665 nm. The modified procedure was successfully applied to the total antioxidant capacity assay of trolox, quercetin, ascorbic acid, gallic acid, catechin, caffeic acid, ferulic acid, rosmarinic acid, glutathione, and cysteine, as well as of lipophilic antioxidants such as α-tocopherol (vitamin E), butylated hydroxyanisole, butylated hydroxytoluene, tertiary butylhydroquinone, lauryl gallate, and β-carotene. The modified FC method reliably quantified ascorbic acid, whereas the conventional method could not. The modified method was reproducible and additive in terms of total antioxidant capacity values of constituents of complex mixtures such as olive oil extract and herbal tea infusion. The trolox equivalent antioxidant capacities of the tested antioxidant compounds correlated well with those found by the Cupric Reducing Antioxidant Capacity reference method.

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

Is There a Role for Oral or Intravenous Ascorbate (Vitamin C) in Treating Patients With Cancer? A Systematic Review

PubMed Central

Hutton, Brian; Ng, Terry; Shorr, Risa; Clemons, Mark

2015-01-01

Background. Many cancer patients receive supplemental ascorbate (vitamin C) in the belief that it synergizes the anticancer effects of chemotherapy and reduces its toxicity. Methods. A systematic review was performed to evaluate the antitumor effects and toxicity of ascorbate treatment. Medline (1946 to March 2014), EMBASE (1947 to March 2014), and the Cochrane central register (1993 to March 2014) were searched for randomized and observational studies. Results. Of 696 identified records, 61 full-text articles were screened and 34 were included. In total, 5 randomized controlled trials (RCTs) (n = 322), 12 phase I/II trials (n = 287), 6 observational studies (n = 7,599), and 11 case reports (n = 267) were identified. Because of study heterogeneity, no meta-analyses were performed. No RCTs reported any statistically significant improvements in overall or progression-free survival or reduced toxicity with ascorbate relative to control arm. Evidence for ascorbate’s antitumor effects was limited to case reports and observational and uncontrolled studies. Conclusion. There is no high-quality evidence to suggest that ascorbate supplementation in cancer patients either enhances the antitumor effects of chemotherapy or reduces its toxicity. Given the high financial and time costs to patients of this treatment, high-quality placebo-controlled trials are needed. PMID:25601965

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.

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.

Altered deoxyribonuclease activity in cancer cells and its role in non toxic adjuvant cancer therapy with mixed vitamins C and K3.

PubMed

Taper, Henryk S

2008-01-01

The alterations of deoxyribonuclease DNase activity in cancer cells were the basis of the utilization of mixed vitamins C and K3 in a nontoxic, adjuvant cancer therapy. In order to localize exactly the altered activities of DNase in cancer cells, histochemical methods were utilized. The deficiency of alkaline and acid DNase activity appeared to be characteristic for non-necrotic cells of malignant human and animal tumors. This enzymatic deficiency appeared in experimental carcinogenesis before the phenotypic signs of malignancy. Tumor promoters directly reduced the activity of both DNases. The incidence of spontaneous malignant human and animal tumors appeared to be inversely proportional to the intensity of the activity of both DNases in normal cells and tissues from which these tumors were derived. The fact that alkaline and acid DNase activity was reactivated during the spontaneous and therapeutically induced necrosis of cancer cells suggests that this enzymatic deficiency of DNase activity in cancer cells was due to the action of specific inhibitors of DNases. Characteristic variations of serum alkaline DNase activity in positive responders to therapy, examined in more than 800 cancer-bearing patients, may be the basis for the development of a useful test for therapeutic prognosis and for monitoring of cancer bearing patients. Acid DNase was selectively reactivated in malignant tumor cells by vitamin C (sodium ascorbate), whereas alkaline DNase was reactivated by vitamin K3. Joint vitamin C and K3 administration produced in vitro and in vivo tumor growth inhibition, potentiation and sensitization of chemo- and/or radiotherapy and a decrease in the number of metastases in animals with experimental tumors. Joint vitamin C and K3 administration may be considered as a possible new, non-toxic, adjuvant cancer therapy, which can be easily introduced into the classic protocols of clinical cancer therapy without any supplementary risk for patients.

Macrophage differentiation increases expression of the ascorbate transporter (SVCT2)

PubMed Central

Qiao, Huan; May, James M.

2013-01-01

To determine whether macrophage differentiation involves increased uptake of vitamin C, or ascorbic acid, we assessed the expression and function of its transporter SVCT2 during phorbol ester-induced differentiation of human-derived THP-1 monocytes. Induction of THP-1 monocyte differentiation by phorbol 12-myristate 13-acetate (PMA) markedly increased SVCT2 mRNA, protein, and function. When ascorbate was present during PMA-induced differentiation, the increase in SVCT2 protein expression was inhibited, but differentiation was enhanced. PMA-induced SVCT2 protein expression was blocked by inhibitors of protein kinase C (PKC), with most of the affect due to the PKCβI and βII isoforms. Activation of MEK/ERK was sustained up to 48 h after PMA treatment, and the inhibitors completely blocked PMA-stimulated SVCT2 protein expression, indicating an exclusive role for the classical MAP kinase pathway. However, inhibitors of NF-κB activation, NADPH oxidase inhibitors, and several antioxidants also partially prevented SVCT2 induction, suggesting diverse distal routes for control of SVCT2 transcription. Both known promoters for the SVCT2 were involved in these effects. In conclusion, PMA-induced monocyte-macrophage differentiation is enhanced by ascorbate and associated with increased expression and function of the SVCT2 protein through a pathway involving sustained activation of PKCβI/II, MAP kinase, NADPH oxidase, and NF-κB. PMID:19232538

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.

Evaluation of synergistic antimicrobial effect of vitamins (A, B1, B2, B6, B12, C, D, E and K) with antibiotics against resistant bacterial strains.

PubMed

Shahzad, Shakeel; Ashraf, M Adnan; Sajid, M; Shahzad, Aqeel; Rafique, Azhar; Mahmood, M Shahid

2018-02-02

Multiple drug resistant super bugs of Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus (MRSA) are becoming challenge for healthcare professionals. In this study, vitamins were evaluated for synergistic activity with the antibiotics. Synergistic effect between antibiotic and stock solutions of vitamins is evaluated by using Kirby-Bauer disc diffusion assay. Distilled water and propylene glycol were used as solvent for water soluble vitamins and fat-soluble vitamins respectively. The final concentration of 10mg/ml of each water-soluble vitamin B1 (Thiamine), B2 (Riboflavin), B6 (Pyridoxine) B12 (Methylcobalamin), C (Ascorbic acid) and 0.1mg/ml of each fat soluble vitamin A (retinol), D (cholecalciferol) E (αTocopherol) K (Menadione) were used with the antibiotics. The results depicted that vitamin K and E have better synergistic activity with piperacillin-tazobactam, imipenem and doripenem antibiotics against A. baumannii. While vitamin B1, B2 and B12 showed remarkable synergistic activity with linezolid against MRSA. Vitamin B1 was further tested to have better synergism with antibiotics oxacillin, tetracycline, rifampicin and linezolid against MRSA. The fat-soluble vitamins E and K were good in synergism against Gram negative A. baumannii while water soluble vitamins as B1, B2 and B12 were effective against MRSA but not against A. baumannii. This synergistic action of vitamins with the antibiotics can be used as a tool to treat multiple drug resistant super bugs with further evaluation at molecular level. Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

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.

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.

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.

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.

A failure in energy metabolism and antioxidant uptake precede symptoms of Huntington's disease in mice.

PubMed

Acuña, Aníbal I; Esparza, Magdalena; Kramm, Carlos; Beltrán, Felipe A; Parra, Alejandra V; Cepeda, Carlos; Toro, Carlos A; Vidal, René L; Hetz, Claudio; Concha, Ilona I; Brauchi, Sebastián; Levine, Michael S; Castro, Maite A

2013-01-01

Huntington's disease has been associated with a failure in energy metabolism and oxidative damage. Ascorbic acid is a powerful antioxidant highly concentrated in the brain where it acts as a messenger, modulating neuronal metabolism. Using an electrophysiological approach in R6/2 HD slices, we observe an abnormal ascorbic acid flux from astrocytes to neurons, which is responsible for alterations in neuronal metabolic substrate preferences. Here using striatal neurons derived from knock-in mice expressing mutant huntingtin (STHdhQ cells), we study ascorbic acid transport. When extracellular ascorbic acid concentration increases, as occurs during synaptic activity, ascorbic acid transporter 2 (SVCT2) translocates to the plasma membrane, ensuring optimal ascorbic acid uptake for neurons. In contrast, SVCT2 from cells that mimic HD symptoms (dubbed HD cells) fails to reach the plasma membrane under the same conditions. We reason that an early impairment of ascorbic acid uptake in HD neurons could lead to early metabolic failure promoting neuronal death.

A failure in energy metabolism and antioxidant uptake precede symptoms of Huntington’s disease in mice

PubMed Central

Acuña, Aníbal I.; Esparza, Magdalena; Kramm, Carlos; Beltrán, Felipe A.; Parra, Alejandra V.; Cepeda, Carlos; Toro, Carlos A.; Vidal, René L.; Hetz, Claudio; Concha, Ilona I.; Brauchi, Sebastián; Levine, Michael S.; Castro, Maite A.

2013-01-01

Huntington’s disease has been associated with a failure in energy metabolism and oxidative damage. Ascorbic acid is a powerful antioxidant highly concentrated in the brain where it acts as a messenger, modulating neuronal metabolism. Using an electrophysiological approach in R6/2 HD slices, we observe an abnormal ascorbic acid flux from astrocytes to neurons, which is responsible for alterations in neuronal metabolic substrate preferences. Here using striatal neurons derived from knock-in mice expressing mutant huntingtin (STHdhQ cells), we study ascorbic acid transport. When extracellular ascorbic acid concentration increases, as occurs during synaptic activity, ascorbic acid transporter 2 (SVCT2) translocates to the plasma membrane, ensuring optimal ascorbic acid uptake for neurons. In contrast, SVCT2 from cells that mimic HD symptoms (dubbed HD cells) fails to reach the plasma membrane under the same conditions. We reason that an early impairment of ascorbic acid uptake in HD neurons could lead to early metabolic failure promoting neuronal death. PMID:24336051

A failure in energy metabolism and antioxidant uptake precede symptoms of Huntington’s disease in mice

NASA Astrophysics Data System (ADS)

Acuña, Aníbal I.; Esparza, Magdalena; Kramm, Carlos; Beltrán, Felipe A.; Parra, Alejandra V.; Cepeda, Carlos; Toro, Carlos A.; Vidal, René L.; Hetz, Claudio; Concha, Ilona I.; Brauchi, Sebastián; Levine, Michael S.; Castro, Maite A.

2013-12-01

Huntington’s disease has been associated with a failure in energy metabolism and oxidative damage. Ascorbic acid is a powerful antioxidant highly concentrated in the brain where it acts as a messenger, modulating neuronal metabolism. Using an electrophysiological approach in R6/2 HD slices, we observe an abnormal ascorbic acid flux from astrocytes to neurons, which is responsible for alterations in neuronal metabolic substrate preferences. Here using striatal neurons derived from knock-in mice expressing mutant huntingtin (STHdhQ cells), we study ascorbic acid transport. When extracellular ascorbic acid concentration increases, as occurs during synaptic activity, ascorbic acid transporter 2 (SVCT2) translocates to the plasma membrane, ensuring optimal ascorbic acid uptake for neurons. In contrast, SVCT2 from cells that mimic HD symptoms (dubbed HD cells) fails to reach the plasma membrane under the same conditions. We reason that an early impairment of ascorbic acid uptake in HD neurons could lead to early metabolic failure promoting neuronal death.

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.

A systematic review of the evidence supporting a causal link between dietary factors and coronary heart disease.

PubMed

Mente, Andrew; de Koning, Lawrence; Shannon, Harry S; Anand, Sonia S

2009-04-13

Although a wealth of literature links dietary factors and coronary heart disease (CHD), the strength of the evidence supporting valid associations has not been evaluated systematically in a single investigation. We conducted a systematic search of MEDLINE for prospective cohort studies or randomized trials investigating dietary exposures in relation to CHD. We used the Bradford Hill guidelines to derive a causation score based on 4 criteria (strength, consistency, temporality, and coherence) for each dietary exposure in cohort studies and examined for consistency with the findings of randomized trials. Strong evidence supports valid associations (4 criteria satisfied) of protective factors, including intake of vegetables, nuts, and "Mediterranean" and high-quality dietary patterns with CHD, and associations of harmful factors, including intake of trans-fatty acids and foods with a high glycemic index or load. Among studies of higher methodologic quality, there was also strong evidence for monounsaturated fatty acids and "prudent" and "western" dietary patterns. Moderate evidence (3 criteria) of associations exists for intake of fish, marine omega-3 fatty acids, folate, whole grains, dietary vitamins E and C, beta carotene, alcohol, fruit, and fiber. Insufficient evidence (< or =2 criteria) of association is present for intake of supplementary vitamin E and ascorbic acid (vitamin C); saturated and polyunsaturated fatty acids; total fat; alpha-linolenic acid; meat; eggs; and milk. Among the dietary exposures with strong evidence of causation from cohort studies, only a Mediterranean dietary pattern is related to CHD in randomized trials. The evidence supports a valid association of a limited number of dietary factors and dietary patterns with CHD. Future evaluation of dietary patterns, including their nutrient and food components, in cohort studies and randomized trials is recommended.

Vitamins C and E in adolescents and young adults with HIV infection.

PubMed

Stephensen, Charles B; Marquis, Grace S; Jacob, Robert A; Kruzich, Laurie A; Douglas, Steven D; Wilson, Craig M

2006-04-01

Oxidative stress during HIV infection may impair immune function, cause more rapid disease progression, and increase requirements for dietary antioxidants such as vitamins C and E. The study had 2 principal objectives. The first was to ascertain whether HIV infection and immune activation were associated with lower plasma concentrations of ascorbate, urate, and alpha- and gamma-tocopherols and with total antioxidant status (TAS). The second objective was to ascertain whether these antioxidants were associated with protection against oxidative damage. This was a cross-sectional study involving 241 HIV-positive and 115 HIV-negative subjects aged 14-23 y. Subjects were primarily female (76%) and African American (70%), and 21% were Hispanic. Plasma ascorbate was significantly lower, but gamma-tocopherol and TAS were significantly higher in subjects with HIV infection when the analysis was adjusted for dietary intake and sex. Plasma alpha-tocopherol did not differ significantly by HIV status. Plasma gamma-tocopherol also was higher in subjects with oxidative damage than in those without such damage. More than 90% of subjects had adequate plasma concentrations for both ascorbate and alpha-tocopherol, although alpha-tocopherol concentrations were lower than expected on the basis of third National Health and Nutrition Examination Survey data. Low plasma ascorbate concentrations in HIV-positive subjects suggest that vitamin C requirements are significantly higher in those with HIV infection. Plasma tocopherol concentrations were not depressed by HIV infection and may be maintained by compensatory mechanisms such as the activity of alpha-tocopherol transfer protein.

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 with either ascorbic acid or catalase, improvement in semen quality was noticed. It was inferred that incorporation of ascorbic acid, catalase and ascorbic acid + chlorpromazine in semen extender improved the post-thaw semen quality in crossbred bulls.

Lessons from comparative physiology: could uric acid represent a physiologic alarm signal gone awry in western society?

PubMed Central

Sautin, Yuri Y.; Oliver, William J.; Roncal, Carlos; Mu, Wei; Sanchez-Lozada, L. Gabriela; Rodriguez-Iturbe, Bernardo; Nakagawa, Takahiko; Benner, Steven A.

2009-01-01

Uric acid has historically been viewed as a purine metabolic waste product excreted by the kidney and gut that is relatively unimportant other than its penchant to crystallize in joints to cause the disease gout. In recent years, however, there has been the realization that uric acid is not biologically inert but may have a wide range of actions, including being both a pro- and anti-oxidant, a neurostimulant, and an inducer of inflammation and activator of the innate immune response. In this paper, we present the hypothesis that uric acid has a key role in the foraging response associated with starvation and fasting. We further suggest that there is a complex interplay between fructose, uric acid and vitamin C, with fructose and uric acid stimulating the foraging response and vitamin C countering this response. Finally, we suggest that the mutations in ascorbate synthesis and uricase that characterized early primate evolution were likely in response to the need to stimulate the foraging “survival” response and might have inadvertently had a role in accelerating the development of bipedal locomotion and intellectual development. Unfortunately, due to marked changes in the diet, resulting in dramatic increases in fructose- and purine-rich foods, these identical genotypic changes may be largely responsible for the epidemic of obesity, diabetes and cardiovascular disease in today’s society. PMID:18649082

Paradoxical effects of vitamin C in Chagas disease.

PubMed

Castanheira, J R P T; Castanho, R E P; Rocha, H; Pagliari, C; Duarte, M I S; Therezo, A L S; Chagas, E F B; Martins, L P A

2018-05-05

Trypanosoma cruzi infection stimulates inflammatory mediators which cause oxidative stress, and the use of antioxidants can minimize the sequelae of Chagas disease. In order to evaluate the efficacy of vitamin C in minimizing oxidative damage in Chagas disease, we orally administered ascorbic acid to Swiss mice infected with 5.0 × 10 4 trypomastigote forms of T. cruzi QM2 strain. These animals were treated for 60 days to investigate the acute phase and 180 days for the chronic phase. During the acute phase, the animals in the infected and treated groups demonstrated lower parasitemia and inflammatory processes were seen in more mice in these groups, probably due to the higher concentration of nitric oxide, which led to the formation of peroxynitrite. The decrease in reduced glutathione concentration in this group showed a circulating oxidant state, and this antioxidant was used to regenerate vitamin C. During the chronic phase, the animals in the infected and treated group showed a decrease in ferric reducing ability of plasma and uric acid concentrations as well as mobilization of bilirubin (which had higher plasma concentration), demonstrating cooperation between endogenous non-enzymatic antioxidants to combat increased oxidative stress. However, lower ferrous oxidation in xylenol orange concentrations was found in the infected and treated group, suggesting that vitamin C provided biological protection by clearing the peroxynitrite, attenuating the chronic inflammatory process in the tissues and favoring greater survival in these animals. Complex interactions were observed between the antioxidant systems of the host and parasite, with paradoxical actions of vitamin C. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

Thermal expansion of L-ascorbic acid

NASA Astrophysics Data System (ADS)

Nicolaï, B.; Barrio, M.; Tamarit, J.-Ll.; Céolin, R.; Rietveld, I. B.

2017-04-01

The specific volume of vitamin C has been investigated by X-ray powder diffraction as a function of temperature from 110 K up to complete degradation around 440 K. Its thermal expansion is relatively small in comparison with other organic compounds with an expansivity α v of 1.2(3) × 10-4 K-1. The structure consists of strongly bound molecules in the ac plane through a dense network of hydrogen bonds. The thermal expansion is anisotropic. Along the b axis, the expansion has most leeway and is about 10 times larger than in the other directions.

Change in chemical constituents and free radical-scavenging activity during Pear (Pyrus pyrifolia) cultivar fruit development.

PubMed

Cho, Jeong-Yong; Lee, Sang-Hyun; Kim, Eun Hee; Yun, Hae Rim; Jeong, Hang Yeon; Lee, Yu Geon; Kim, Wol-Soo; Moon, Jae-Hak

2015-01-01

Changes in chemical constituent contents and DPPH radical-scavenging activity in fruits of pear (Pyrus pyrifolia) cultivars during the development were investigated. The fruits of seven cultivars (cv. Niitaka, Chuhwangbae, Wonhwang, Hwangkeumbae, Hwasan, Manpungbae, and Imamuraaki) were collected at 15-day intervals after day 20 of florescence. Vitamins (ascorbic acid and α-tocopherol), arbutin, chlorogenic acid, malaxinic acid, total caffeic acid, total flavonoids, and total phenolics were the highest in immature pear fruit on day 20 after florescence among samples at different growth stages. All of these compounds decreased gradually in the fruit during the development. Immature pear fruit on day 35 or 50 after florescence exhibited higher free radical-scavenging activity than that at other times, although activities were slightly different among cultivars. The chemical constituent contents and free radical-scavenging activity were largely different among immature fruits of the pear cultivars, but small differences were observed when they matured.

A simple method for plasma total vitamin C analysis suitable for routine clinical laboratory use.

PubMed

Robitaille, Line; Hoffer, L John

2016-04-21

In-hospital hypovitaminosis C is highly prevalent but almost completely unrecognized. Medical awareness of this potentially important disorder is hindered by the inability of most hospital laboratories to determine plasma vitamin C concentrations. The availability of a simple, reliable method for analyzing plasma vitamin C could increase opportunities for routine plasma vitamin C analysis in clinical medicine. Plasma vitamin C can be analyzed by high performance liquid chromatography (HPLC) with electrochemical (EC) or ultraviolet (UV) light detection. We modified existing UV-HPLC methods for plasma total vitamin C analysis (the sum of ascorbic and dehydroascorbic acid) to develop a simple, constant-low-pH sample reduction procedure followed by isocratic reverse-phase HPLC separation using a purely aqueous low-pH non-buffered mobile phase. Although EC-HPLC is widely recommended over UV-HPLC for plasma total vitamin C analysis, the two methods have never been directly compared. We formally compared the simplified UV-HPLC method with EC-HPLC in 80 consecutive clinical samples. The simplified UV-HPLC method was less expensive, easier to set up, required fewer reagents and no pH adjustments, and demonstrated greater sample stability than many existing methods for plasma vitamin C analysis. When compared with the gold-standard EC-HPLC method in 80 consecutive clinical samples exhibiting a wide range of plasma vitamin C concentrations, it performed equivalently. The easy set up, simplicity and sensitivity of the plasma vitamin C analysis method described here could make it practical in a normally equipped hospital laboratory. Unlike any prior UV-HPLC method for plasma total vitamin C analysis, it was rigorously compared with the gold-standard EC-HPLC method and performed equivalently. Adoption of this method could increase the availability of plasma vitamin C analysis in clinical medicine.

Quantification of Mesophyll Resistance and Apoplastic Ascorbic Acid as an Antioxidant for Tropospheric Ozone in Durum Wheat (Triticum durum Desf. cv. Camacho)

PubMed Central

de la Torre, Daniel

2008-01-01

The daily variations in cellular and apoplastic ascorbic acid and dehydroascorbic acid levels in a Mediterranean durum wheat cultivar (Triticum durum Desf. cv. Camacho) were analyzed in order to relate them to ambient ozone exposure and to subsequent stomatally absorbed ozone fluxes. The aim of this study is to prove the effectiveness and accuracy of a computer model (SODA) to calculate the mesophyll resistance (rm) to ozone uptake, the percentage of ozone detoxification by apoplastic ascorbic acid, and the ozone flux to the plasmalemma (Fm) in a Mediterranean durum wheat cultivar. These calculated factors were related to apoplastic ascorbic acid levels and to ambient ozone concentrations. These relationships were obtained with a view to explaining the detoxification of ozone by apoplastic ascorbic acid. Ozone detoxifications of up to 52% were found at midday, when maximum ozone concentrations and maximum apoplastic ascorbic acid are seen. Mesophyll resistance was minimum at this time, and ozone flux to the plasmalemma was reduced because of the reaction of ozone with apoplastic ascorbic acid. PMID:19082416

Quantification of mesophyll resistance and apoplastic ascorbic acid as an antioxidant for tropospheric ozone in durum wheat (Triticum durum Desf. cv. Camacho).

PubMed

de la Torre, Daniel

2008-12-14

The daily variations in cellular and apoplastic ascorbic acid and dehydroascorbic acid levels in a Mediterranean durum wheat cultivar (Triticum durum Desf. cv. Camacho) were analyzed in order to relate them to ambient ozone exposure and to subsequent stomatally absorbed ozone fluxes. The aim of this study is to prove the effectiveness and accuracy of a computer model (SODA) to calculate the mesophyll resistance (rm) to ozone uptake, the percentage of ozone detoxification by apoplastic ascorbic acid, and the ozone flux to the plasmalemma (Fm) in a Mediterranean durum wheat cultivar. These calculated factors were related to apoplastic ascorbic acid levels and to ambient ozone concentrations. These relationships were obtained with a view to explaining the detoxification of ozone by apoplastic ascorbic acid. Ozone detoxifications of up to 52% were found at midday, when maximum ozone concentrations and maximum apoplastic ascorbic acid are seen. Mesophyll resistance was minimum at this time, and ozone flux to the plasmalemma was reduced because of the reaction of ozone with apoplastic ascorbic acid.

Investigation of the antioxidant status in multiple myeloma patients: effects of therapy.

PubMed

Mehdi, Wesen A; Zainulabdeen, Jwan A; Mehde, Atheer A

2013-01-01

Multiple myeloma is a malignant silent incurable plasma cell disorder. The present study aimed to assessed the activation of the oxidative stress pathway in affected patients. Advanced oxidation protein products (AOPPs), malondialdehyde (MDA), adenosine deaminase (ADA), total antioxidant capacity (TAC) levels, glutathione, ascorbic acid (vitamin C), α-tocopherol (vitamin E) in addition to related enzymes glutathione peroxidase (GSH-Px), glutathione reductase (GSH-R) and superoxide dismutase (SOD) were analyzed in sixty patients with multiple myeloma before and after one month treatment with induction therapy. The results of the study showed a significant elevation in AOPPs, MDA, ADA levels in patients with multiple myeloma before and after treatment in comparison to healthy control samples In contrast TAC glutathione, vitamin C and E, and the antioxidant enzymes levels were decreased significantly. On comparing samples of MM patients after treatment, there was significant increase of TAC glutathione, vitamin C and E, and the antioxidant enzymes in parallel with decreasing AOPPs, MDA and ADA levels in comparison with samples of patients before treatment. The results indicate oxidative stress and DNA damage activity increase in MM and are alleviated in response to therapy.

Scurvy: a new problem for patients with chronic GVHD involving mucous membranes; an easy problem to resolve.

PubMed

Kletzel, Morris; Powers, Kim; Hayes, Meghan

2014-08-01

Vitamin C deficiency in developed countries is typically observed in patients with unique clinical conditions such as cystic fibrosis or anorexia nervosa, or in patients on long-term tube feeds. We report here a clinical observation in six pediatric and adolescent patients (median age 17.5 yr, range 9.8-23.5 yr) with chronic GVHD with mucous membrane involvement found to be vitamin C deficient. These patients' baseline serum vitamin C levels ranged from <0.12 to 0.94 mg/dL (normal value 0.20-1.90 mg/dL), with a mean level 0.56 ± 0.36 mg/dL and a median level 0.6 mg/dL. Among these patients, signs and symptoms of mucositis failed to respond to standard chronic GVHD therapy. After receiving treatment with 2000 mg of ascorbic acid by mouth, daily patients displayed increased serum vitamin C levels. Clinically, this correlated with a remarkable improvement in patients' mucositis and ability to eat. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Supplementing with vitamin C the diet of honeybees (Apis mellifera carnica) parasitized with Varroa destructor: effects on antioxidative status.

PubMed

Farjan, Marek; Łopieńska-Biernat, Elżbieta; Lipiński, Zbigniew; Dmitryjuk, Małgorzata; Żółtowska, Krystyna

2014-05-01

We studied a total of eight developmental stages of capped brood and newly emerged workers of Apis mellifera carnica colonies naturally parasitized with Varroa destructor. During winter and early spring four colonies were fed syrup containing 1.8 mg vitamin C kg(-1) (ascorbic acid group; group AA) while four colonies were fed syrup without the vitamin C (control group C). Selected elements of the antioxidative system were analysed including total antioxidant status (TAS), glutathione content and antioxidative enzyme activities (superoxide dismutase, catalase, peroxidase and glutathione S-transferase). Body weight, protein content and indices of infestation were also determined. The prevalence (8.11%) and intensity (1·15 parasite per bee) of the infestation were lower in group AA compared with group C (11.3% and 1.21, respectively). Changes in the indicators of antioxidative stress were evidence for the strengthening of the antioxidative system in the brood by administration of vitamin C. In freshly emerged worker bees of group AA, despite the infestation, protein content, TAS, and the activity of all antioxidative enzymes had significantly higher values in relation to group C.

Does Vitamin C Influence Neurodegenerative Diseases and Psychiatric Disorders?

PubMed Central

Luchowska-Kocot, Dorota; Kiełczykowska, Małgorzata; Musik, Irena; Kurzepa, Jacek

2017-01-01

Vitamin C (Vit C) is considered to be a vital antioxidant molecule in the brain. Intracellular Vit C helps maintain integrity and function of several processes in the central nervous system (CNS), including neuronal maturation and differentiation, myelin formation, synthesis of catecholamine, modulation of neurotransmission and antioxidant protection. The importance of Vit C for CNS function has been proven by the fact that targeted deletion of the sodium-vitamin C co-transporter in mice results in widespread cerebral hemorrhage and death on post-natal day one. Since neurological diseases are characterized by increased free radical generation and the highest concentrations of Vit C in the body are found in the brain and neuroendocrine tissues, it is suggested that Vit C may change the course of neurological diseases and display potential therapeutic roles. The aim of this review is to update the current state of knowledge of the role of vitamin C on neurodegenerative diseases including Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, multiple sclerosis and amyotrophic sclerosis, as well as psychiatric disorders including depression, anxiety and schizophrenia. The particular attention is attributed to understanding of the mechanisms underlying possible therapeutic properties of ascorbic acid in the presented disorders. PMID:28654017

Protective and Therapeutic Agents for War Gases - Solutions of BAL

DTIC Science & Technology

1945-04-02

Ascorbic Acid 1.07 Thiosorbitol :7 7§ Catechol 1.07 Menthol p-Toluene Sulfinic Gum Tragacanth .76 Acid 1.07 Glycine .74 Formamidlne Sulfinic...Hydrazine hydrochlorlde d-iao-ascorbic acid Iflcotlnlc acid Ascorbic acid "Avonex" (oat flour concentrate) Sulfanilamide Camphor Menthol Thiodiglycol

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

Direct spectrophotometric measurement of supra-physiological levels of ascorbate in plasma.

PubMed

Witmer, Jordan R; Wetherell, Bailey J; Wagner, Brett A; Du, Juan; Cullen, Joseph J; Buettner, Garry R

2016-08-01

Supra-physiological concentrations of ascorbate, vitamin C, in blood, greater than 1mM, achieved through intravenous administration (IV), are being tested in clinical trials to treat human disease, e.g. cancer. These trials need information on the high levels of ascorbate achieved in blood upon IV administration of pharmacological ascorbate so appropriate clinical decisions can be made. Here we demonstrate that in the complex matrix of human blood plasma supra-physiological levels of ascorbate can be quantified by direct UV spectroscopy with use of a microvolume UV-vis spectrophotometer. Direct quantitation of ascorbate in plasma in the range of 2.9mM, lower limit of detection, up to at least 35mM can be achieved without any sample processing, other than centrifugation. This approach is rapid, economical, and can be used to quantify supraphysiological blood levels of ascorbate associated with the use of IV administration of pharmacological ascorbate to treat disease. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

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

A highly sensitive and selective detection of Cr(VI) and ascorbic acid based on nitrogen-doped carbon dots.

PubMed

Zhang, Yuhua; Fang, Xian; Zhao, Hong; Li, Zengxi

2018-05-01

A highly sensitive and selective detection of hexavalent chromium (Cr(VI)) and ascorbic acid (AA) was proposed using nitrogen-doped carbon dots (N-CDs). In the absence of AA, the quantitative detection of Cr(VI) was realized through Cr(VI) acting as a quencher to quench the fluorescence of N-CDs by inner filter effect (IFE) and static quenching effect. Under the optimal conditions, the linear range for Cr(VI) detection was from 0.01 to 250μM with a detection limit of 5nM (S/N = 3). In the presence of AA, the fluorescence intensity could be rapidly enhanced compared with the fluorescence of N-CDs/Cr(VI) system since Cr(VI) can be reduced into trivalent chromium (Cr(III)) by AA. And a wide linear range for AA detection was obtained from 1 to 750μM. The detection limit was 0.3μM (S/N = 3). More importantly, this method can be successfully applied to the detection of Cr(VI) in real water samples, and AA in vitamins C tablets and human serum sample. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of various halide salts on the incompatibility of cyanocobalamin and ascorbic acid in aqueous solution.

PubMed

Ichikawa, Makoto; Ide, Nagatoshi; Shiraishi, Sumihiro; Ono, Kazuhisa

2005-06-01

Combination of cyanocobalamin (VB12) and ascorbic acid (VC) has been widely seen in pharmaceutical products and dietary supplements. However, VB12 has been reported that its behavior in stability in aqueous solution is quite different when VC is mixed. In the present study, we examined the stabilities of these vitamins in acetate buffer (pH 4.8) using high performance liquid chromatography. Degradation of VB12 was not observed in the absence of VC in the buffer. However, when VC was mixed in the VB12 solution, VB12 concentrations decreased in accordance with VC degradation. VB12 and VC degradations were inhibited by adding sodium halides to acetate buffer at pH 4.8. These stabilization effects were also observed in the range from pH 3.5 to 5.3 and by adding potassium, magnesium, and calcium halides. Furthermore, our data demonstrated that increases in the halide anion concentrations and atomic number (Cl-

BIOCHEMICAL IMPLICATIONS OF PRO-OXIDANTS AND ANTIOXIDANTS

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

Bernheim, F.

1963-01-01

Lipid peroxides can be detected in intact adipose tissue cells but have not been shown to be present in other normal cells. On injury of such cells, they are rapidly formed. This post-injury formation is dependent on traces of inorganic iron liberated from a protein- or hematin-bound state. Ascorbic acid acts as a co-oxidant in the reaction. The iron-catalyzed reaction can be inhibited by the addition of chelating agents, including free fatty acids, or by antioxidants such as vitamin E added in vitro. Adding excess vitamin E to the diet also decreases lipid peroxidation in the injured cells. Tissues inmore » which cell division is continuously occurring (bone marrow, tumors, intestinal mucosa) produce no lipid peroxides even after the cells are injured. Antioxidant activity in these cells must be exceptionaliy high. Analysis of the conditions in intestinal mucosa shows that phospholipase activity can be correlated with antioxidant activity. After irradiation, the virtual absence of a cofactor reduces the phospholipase activity and reduces the antioxidant to the same extent. The nature of the antioxidant in bone marrow and tumor is still unknown. (auth)« less

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."

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.

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. ...

Extending the spectrum of α-dicarbonyl compounds in vivo.

PubMed

Henning, Christian; Liehr, Kristin; Girndt, Matthias; Ulrich, Christof; Glomb, Marcus A

2014-10-10

Maillard α-dicarbonyl compounds are known as central intermediates in advanced glycation end product (AGE) formation. Glucose is the primary source of energy for the human body, whereas l-threo-ascorbic acid (vitamin C) is an essential nutrient, involved in a variety of enzymatic reactions. Thus, the Maillard degradation of glucose and ascorbic acid is of major importance in vivo. To understand the complex mechanistic pathways of AGE formation, it is crucial to extend the knowledge on plasma concentrations of reactive key α-dicarbonyl compounds (e.g. 1-deoxyglucosone). With the present work, we introduce a highly sensitive LC-MS/MS multimethod for human blood plasma based on derivatization with o-phenylenediamine under acidic conditions. The impact of workup and reaction conditions, particularly of pH, was thoroughly evaluated. A comprehensive validation provided the limit of detection, limit of quantitation, coefficients of variation, and recovery rates. The method includes the α-dicarbonyls 1-deoxyglucosone, 3-deoxyglucosone, glucosone, Lederer's glucosone, dehydroascorbic acid, 2,3-diketogulonic acid, 1-deoxypentosone, 3-deoxypentosone, 3,4-dideoxypentosone, pentosone, 1-deoxythreosone, 3-deoxythreosone, threosone, methylglyoxal, glyoxal; the α-keto-carboxylic acids pyruvic acid and glyoxylic acid; and the dicarboxylic acid oxalic acid. The method was then applied to the analyses of 15 healthy subjects and 24 uremic patients undergoing hemodialysis. The comparison of the results revealed a clear shift in the product spectrum. In most cases, the plasma levels of target analytes were significantly higher. Thus, this is the first time that a complete spectrum of α-dicarbonyl compounds relevant in vivo has been established. The results provide further insights into the chemistry of AGE formation and will be helpful to find specific markers to differentiate between the various precursors of glycation. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

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.

Distinctive Glycerophospholipid Profiles of Human Seminoma and Adjacent Normal Tissues by Desorption Electrospray Ionization Imaging Mass Spectrometry

NASA Astrophysics Data System (ADS)

Masterson, Timothy A.; Dill, Allison L.; Eberlin, Livia S.; Mattarozzi, Monica; Cheng, Liang; Beck, Stephen D. W.; Bianchi, Federica; Cooks, R. Graham

2011-08-01

Desorption electrospray ionization mass spectrometry (DESI-MS) has been successfully used to discriminate between normal and cancerous human tissue from different anatomical sites. On the basis of this, DESI-MS imaging was used to characterize human seminoma and adjacent normal tissue. Seminoma and adjacent normal paired human tissue sections (40 tissues) from 15 patients undergoing radical orchiectomy were flash frozen in liquid nitrogen and sectioned to 15 μm thickness and thaw mounted to glass slides. The entire sample was two-dimensionally analyzed by the charged solvent spray to form a molecular image of the biological tissue. DESI-MS images were compared with formalin-fixed, hematoxylin and eosin (H&E) stained slides of the same material. Increased signal intensity was detected for two seminolipids [seminolipid (16:0/16:0) and seminolipid (30:0)] in the normal tubule testis tissue; these compounds were undetectable in seminoma tissue, as well as from the surrounding fat, muscle, and blood vessels. A glycerophosphoinositol [PI(18:0/20:4)] was also found at increased intensity in the normal testes tubule tissue when compared with seminoma tissue. Ascorbic acid (i.e., vitamin C) was found at increased amounts in seminoma tissue when compared with normal tissue. DESI-MS analysis was successfully used to visualize the location of several types of molecules across human seminoma and normal tissues. Discrimination between seminoma and adjacent normal testes tubules was achieved on the basis of the spatial distributions and varying intensities of particular lipid species as well as ascorbic acid. The increased presence of ascorbic acid within seminoma compared with normal seminiferous tubules was previously unknown.

Nutrient intake and meal patterns of Micmac indian and Caucasian women in Shubenacadie, NS.

PubMed Central

Johnston, J. L.; Williams, C. N.; Weldon, K. L.

1977-01-01

North American Indians have a higher morbidity from gallbladder disease, diabetes mellitus and obesity than other North Americans; this may result from their food intake. Nutrient intake and meal patterns were compared in 120 Micmac Indian and 115 Caucasian women in Shubenacadie, NS. Findings were compared with the Canadian Dietary Standard (CDS) and the Nutrition Canada national and Indian survey reports. The diet of Indian women had higher carbohydrate, lower protein and lower fibre content than that of Caucasian women, who derived a higher percentage of energy from protein and had a higher intake of vitamin A, niacin and ascorbic acid. Overnight fast was longer among Indian women. A high percentage of all women studied reported diets that did not reach the CDS for total energy intake in kilocalories or for calcium, iron, vitamin A, thiamin or riboflavin. PMID:861896

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®

Ascorbic acid deficiency decreases hepatic cytochrome P-450, especially CYP2B1/2B2, and simultaneously induces heme oxygenase-1 gene expression in scurvy-prone ODS rats.

PubMed

Kobayashi, Misato; Hoshinaga, Yukiko; Miura, Natsuko; Tokuda, Yuki; Shigeoka, Shigeru; Murai, Atsushi; Horio, Fumihiko

2014-01-01

The mechanisms underlying the decrease in hepatic cytochrome P-450 (CYP) content in ascorbic acid deficiency was investigated in scurvy-prone ODS rats. First, male ODS rats were fed a diet containing sufficient ascorbic acid (control) or a diet without ascorbic acid (deficient) for 18 days, with or without the intraperitoneal injection of phenobarbital. Ascorbic acid deficiency decreased hepatic microsomal total CYP content, CYP2B1/2B2 protein, and mitochondrial cytochrome oxidase (COX) complex IV subunit I protein, and simultaneously increased heme oxygenase-1 protein in microsomes and mitochondria. Next, heme oxygenase-1 inducers, that is lipopolysaccharide and hemin, were administered to phenobaribital-treated ODS rats fed sufficient ascorbic acid. The administration of these inducers decreased hepatic microsomal total CYP content, CYP2B1/2B2 protein, and mitochondrial COX complex IV subunit I protein. These results suggested that the stimulation of hepatic heme oxygenase-1 expression by ascorbic acid deficiency caused the decrease in CYP content in liver.

Ascorbic acid supplementation partially prevents the delayed reproductive development in juvenile male rats exposed to rosuvastatin since prepuberty.

PubMed

Leite, Gabriel Adan Araújo; Figueiredo, Thamiris Moreira; Sanabria, Marciana; Dias, Ana Flávia Mota Gonçalves; Silva, Patrícia Villela E; Martins Junior, Airton da Cunha; Barbosa Junior, Fernando; Kempinas, Wilma De Grava

2017-10-01

Dyslipidemias are occurring earlier in the population due to the increase of obesity and bad eating habits. Rosuvastatin inhibits the enzyme HMG-CoA reductase, decreasing total cholesterol. Ascorbic acid is an important antioxidant compound for male reproductive system. This study aimed to evaluate whether ascorbic acid supplementation may prevent the reproductive damage provoked by rosuvastatin administration at prepuberty. Male pups were distributed into six experimental groups that received saline solution 0.9%, 3 or 10mg/kg/day of rosuvastatin, 150mg/day of ascorbic acid, or 150mg/day of ascorbic acid associated with 3 or 10mg/kg/day of rosuvastatin from post-natal day (PND) 23 until PND53. Rosuvastatin-treated groups showed delayed puberty installation, androgen depletion and impairment on testicular and epididymal morphology. Ascorbic acid partially prevented these reproductive damages. In conclusion, rosuvastatin exposure is a probable risk to reproductive development and ascorbic acid supplementation may be useful to prevent the reproductive impairment of rosuvastatin exposure. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of vitamin C concentration and co-injection with calcium chloride on beef retail display color.

PubMed

Wheeler, T L; Koohmaraie, M; Shackelford, S D

1996-08-01

The objectives of these experiments were to determine 1) the most effective vitamin C concentration to stabilize color of beef cuts during retail display and 2) the effect on color of incorporating vitamin C into a calcium chloride (CaCl2) injection solution. Top round cuts (semimembranosus and adductor) were injected with 5% by weight of a 0, .25, .5, 1, 2, or 4% sodium ascorbate solution (Exp. 1) or a 0, .5, 1, or 1.5% sodium ascorbate solution (Exp. 2). In Exp. 1, vitamin C resulted in more (P < .05) stable lean color during 9 degrees C display, and .5, 1, and 2% vitamin C were most (P < .05) effective. In Exp. 2, all concentrations of vitamin C maintained redder (P < .05) steaks after 3, 5, and 7 d of display than control steaks and had a lower (P < .05) percentage of surface discoloration after 5 and 7 d of display at 1 degree C. Experiment 3 used beef bottom round cuts (biceps femoris) to compare control, vitamin C- (1%), CaCl2-(200 mM) and vitamin C + CaCl2-treated steaks displayed at 1 degree C. Calcium chloride-treated steaks were more (P < .05) brown and had a higher (P < .05) percentage of surface discoloration on d 5 and 7 than control steaks, whereas steaks treated with vitamin C or vitamin C + CaCl2 were more (P < .05) red and had lower (P < .05) discoloration on d 5 and 7 than control steaks. Vitamin C can be injected into beef subprimals to enhance lean color stability and extend retail display life. Vitamin C also can be used in combination with CaCl2 to offset potential color deterioration, after 5 d of display, due to salt-induced oxidation.

Activity of a sodium-dependent vitamin C transporter (SVCT) in MDCK-MDR1 cells and mechanism of ascorbate uptake

PubMed Central

Luo, Shuanghui; Wang, Zhiying; Kansara, Viral; Pal, Dhananjay; Mitra, Ashim. K.

2008-01-01

The objective of this research was to functionally characterize sodium-dependent vitamin C transporter (SVCT) in MDCK-MDR1 cells and to study the effect of substituted benzene derivatives on the intracellular accumulation of ascorbic acid (AA). Mechanism of AA uptake and transport was delineated. Uptake of [14C]ascorbic acid ([14C]AA) was studied in the absence and presence of excess unlabelled AA, anion transporter inhibitors, and a series of mono- and di- substituted benzenes. Transepithelial transport of [14C]AA across polarized cell membrane has been studied for the first time. Role of cellular protein kinase mediated pathways on the regulation of AA uptake has been investigated. The cellular localizations of SVCTs were observed using confocal microscopy. Uptake of AA was found to be saturable with a Km of 83.2 μM and Vmax of 94.2 pmol/min/mg protein for SVCT1. The process was pH, sodium, temperature, and energy dependent. It was under the regulation of cellular protein kinase C (PKC) and Ca2+/CaM mediated pathways. [14C]AA uptake was significantly inhibited in the presence of excess unlabelled AA and a series of electron-withdrawing group i.e. halogen- and nitro- substituted benzene derivatives. AA appears to translocate across polarized cell membrane from apical to basal side (A−B) as well as basal to apical side (B−A) at a similar permeability. It appears that SVCT1 was mainly expressed on the apical side and SVCT2 may be located on both apical and basal sides. In conclusion, SVCT has been functionally characterized in MDCK-MDR1 cells. The interference of a series of electrophile substituted benzenes on the AA uptake process may be explained by their structural similarity. SVCT may be targeted to facilitate the delivery of drugs with low bioavailability by conjugating with AA and its structural analogs. MDCK-MDR1 cell line may be utilized as an in vitro model to study the permeability of AA conjugated prodrugs. PMID:18417304

Vitamin C protects rat cerebellum and encephalon from oxidative stress following exposure to radiofrequency wave generated by a BTS antenna model.

PubMed

Akbari, Abolfazl; Jelodar, Gholamali; Nazifi, Saeed

2014-06-01

Radio frequency wave (RFW) generated by base transceiver station has been reported to produce deleterious effects on the central nervous system function, possibly through oxidative stress. This study was conducted to evaluate the effect of RFW-induced oxidative stress in the cerebellum and encephalon and the prophylactic effect of vitamin C on theses tissues by measuring the antioxidant enzymes activity, including: glutathione peroxidase, superoxide dismutase, catalase, and malondialdehyde (MDA). Thirty-two adult male Sprague-Dawley rats were randomly divided into four equal groups. The control group; the control-vitamin C group received L-ascorbic acid (200 mg/kg of body weight/day by gavage) for 45 days. The RFW group was exposed to RFW and the RFW+ vitamin C group was exposed to RFW and received vitamin C. At the end of the experiment, all groups were killed and encephalon and cerebellum of all rats were removed and stored at -70 °C for measurement of antioxidant enzymes activity and MDA. The results indicate that exposure to RFW in the test group decreased antioxidant enzymes activity and increased MDA compared with the control groups (p < 0.05). The protective role of vitamin C in the treated group improved antioxidant enzymes activity and reduced MDA compared with the test group (p < 0.05). It can be concluded that RFW causes oxidative stress in the brain and vitamin C improves the antioxidant enzymes activity and decreases MDA.

Vitamin Content of Breast Milk From HIV-1–Infected Mothers Before and After Flash-Heat Treatment

PubMed Central

Israel-Ballard, Kiersten A.; Abrams, Barbara F.; Coutsoudis, Anna; Sibeko, Lindiwe N.; Cheryk, Lynn A.; Chantry, Caroline J.

2010-01-01

Background World Health Organization advocates heat treatment of expressed breastmilk (EBM) as one method to reduce postnatal transmission of human immunodeficiency virus (HIV) in developing countries. Flash-heat is a simple heat treatment method shown to inactivate cell-free HIV. Objective To determine the effect of flash-heat on vitamin content of milk. Methods Fresh EBM was collected from 50 HIV+ mothers in Durban, South Africa. Mothers washed their hands and then manually expressed 75–150 mL EBM into sterile jars. Milk was aliquoted to unheated controls or flash-heat (50 mL EBM in a glass jar heated in a 450-mL water jacket in an aluminum pan until water boiled, then EBM removed) simulating field conditions with an open flame. Samples were stored at −70°C and then analyzed for the effect of flash-heat on vitamins [A, ascorbic acid, riboflavin (B2), pyridoxal-5-phosphate (B6), folate, and B12]. Results Vitamin A was not significantly affected by flash-heat and vitamins B12 and C and folate increased significantly. Vitamins B2 and B6 were decreased to 59% (95% confidence interval 44 to 81) and 96% (95% confidence interval 92 to 99), respectively, of that found in unheated milk. Conclusions The percentage remaining after flash-heat suggests that most vitamin concentrations are retained after heating. Flash-heat may be a practical and nutritious infant feeding method for mothers in developing countries. PMID:18614920

Vitamin content of breast milk from HIV-1-infected mothers before and after flash-heat treatment.

PubMed

Israel-Ballard, Kiersten A; Abrams, Barbara F; Coutsoudis, Anna; Sibeko, Lindiwe N; Cheryk, Lynn A; Chantry, Caroline J

2008-08-01

World Health Organization advocates heat treatment of expressed breastmilk (EBM) as one method to reduce postnatal transmission of human immunodeficiency virus (HIV) in developing countries. Flash-heat is a simple heat treatment method shown to inactivate cell-free HIV. To determine the effect of flash-heat on vitamin content of milk. Fresh EBM was collected from 50 HIV+ mothers in Durban, South Africa. Mothers washed their hands and then manually expressed 75-150 mL EBM into sterile jars. Milk was aliquoted to unheated controls or flash-heat (50 mL EBM in a glass jar heated in a 450-mL water jacket in an aluminum pan until water boiled, then EBM removed) simulating field conditions with an open flame. Samples were stored at -70 degrees C and then analyzed for the effect of flash-heat on vitamins [A, ascorbic acid, riboflavin (B2), pyridoxal-5-phosphate (B6), folate, and B12]. Vitamin A was not significantly affected by flash-heat and vitamins B12 and C and folate increased significantly. Vitamins B2 and B6 were decreased to 59% (95% confidence interval 44 to 81) and 96% (95% confidence interval 92 to 99), respectively, of that found in unheated milk. The percentage remaining after flash-heat suggests that most vitamin concentrations are retained after heating. Flash-heat may be a practical and nutritious infant feeding method for mothers in developing countries.

Physiochemical Properties of the Pulp and Almonds of TUCUMÃ (Astrocaryum vulgare Mart) for Oil Production

NASA Astrophysics Data System (ADS)

Longo, R. M.; Ribeiro, A. I.; Melo, W. J.; Queiroz, M. R.; Russo, A. C.; Amaral, J. B.

2009-04-01

Tucumã (Astrocaryum vulgare Mart) it is a palm tree commonly found at the Amazonian forest of firm earth, it produces nutritious fruits, quite appreciated by the local population. The seeds are for the obtaining of eatable olive oil and soap, the endocarp is employee for the local population in the making of earrings, rings, bracelets, necklaces and other workmanships. This species has occurrence also in Acre, Rondônia, Pará, Mato Grosso, Roraima, Trindad, Guyana and Bolivia. The objective of this work was to accomplish mechanical tests on the fruits with the purpose of studying the rupture of the shell and the whole income almonds and to obtain the impact loads in tucumã fruits. It was also characterized biochemical compositions of the pulp and the almond seeking the use for the other ends. The physiochemical parameters analyzed were: moisture content, fats gray, total protein, fiber, carbohydrate, calorie, fats acids and vitamins, just in the pulp: vitamin E, vitamin B1, vitamin B2, vitamin B5, vitamin B3, vitamin B6, vitamin B12, vitamin C, vitamin D3 and vitamin E. The obtained results revealed that the maximum force of rupture was of approximately 6200 N for the direction apex-insert and 7200 N for the perpendicular direction; then this the tucumã fruit with high shell hardness when compared to the other types of chestnuts, being necessary studies to design machines capable to promote mechanical breaking and thus facilitating, its commercial exploration. The pulp of the tucumã fruits, presented a significant amount of fats (32%), following by carbohydrates (19,7%) and fibers (18,4). The caloric value was of 380 Kcal/g. Also the pulp presented good amount of vitamin B3 (niacin - 76,7%) and C (acid ascorbic - 23,6%). In relation to the fat acids the pulp presents contents of acid oleic (C18.1) about 72,8% following for linoléico (C18.2), being a good product for the human and animal feeding,. In the almond 24,2% of fiber, 10,7% of fats, 17,0% of carbohydrates and 4,3% of total protein were found. The caloric value was around 180 kcal/g. The difference between these values and other from literatures. Was observed probably the nutritional values of the tucumã vary so much with the variety as with the maturation stadium in that is the fruit. The almond of the tucumã presented contents of 50,82% of C12 (láurico)e 24,98% C14 (miristico). It is a quite interesting and very spread fruit among the local communities, especially in lands that already suffered human actions, as the introduction of pastures and where its crop in extraction areas, not causing this way, larger damages to the forest. Key Words: rupture force, fat acid, oil

Determination of selected water-soluble vitamins using hydrophilic chromatography: a comparison of photodiode array, fluorescence, and coulometric detection, and validation in a breakfast cereal matrix.

PubMed

Langer, Swen; Lodge, John K

2014-06-01

Water-soluble vitamins are an important class of compounds that require quantification from food sources to monitor nutritional value. In this study we have analysed six water-soluble B vitamins ([thiamine (B1), riboflavin (B2), nicotinic acid (B3, NAc), nicotinamide (B3, NAm), pyridoxal (B6), folic acid (B9)], and ascorbic acid (vit C) with hydrophilic interaction liquid chromatography (HILIC), and compared UV, fluorescent (FLD) and coulometric detection to optimise a method to quantitate the vitamins from food sources. Employing UV/diode array (DAD) and fluorimetric detection, six B vitamins were detected in a single run using gradient elution from 100% to 60% solvent B [10mM ammonium acetate, pH 5.0, in acetonitrile and water 95:5 (v:v)] over 18 min. UV detection was performed at 268 nm for B1, 260 nm for both B3 species and 284 nm for B9. FLD was employed for B2 at excitation wavelength of 268 nm, emission of 513 nm, and 284 nm/317 nm for B6. Coulometric detection can be used to detect B6 and B9, and vit C, and was performed isocratically at 75% and 85% of solvent B, respectively. B6 was analysed at a potential of 720 mV, while B9 was analysed at 600 mV, and vit C at 30 mV. Retention times (0.96 to 11.81 min), intra-day repeatability (CV 1.6 to 3.6), inter-day variability (CV 1.8 to 11.1), and linearity (R 0.9877 to 0.9995) remained good under these conditions with limits of detection varying from 6.6 to 164.6 ng mL(-1), limits of quantification between 16.8 and 548.7 ng mL(-1). The method was successfully applied for quantification of six B vitamins from a fortified food product and is, to our knowledge, the first to simultaneously determine multiple water-soluble vitamins extracted from a food matrix using HILIC. Copyright © 2014 Elsevier B.V. All rights reserved.

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

Suppressive effects of retinoids, carotenoids and antioxidant vitamins on heterocyclic amine-induced umu C gene expression in Salmonella typhimurium (TA 1535/pSK 1002).

PubMed

Okai, Y; Higashi-Okai, K; Nakamura, S; Yano, Y; Otani, S

1996-06-12

Effects of retinoids, carotenoids and antioxidant vitamins were studied by mutagen-induced umu C gene expression system in Salmonella typhimurium (TA 1535/pSK 1002). Retinol (vitamin A), retinol acetate and retinoic acid showed remarkable inhibitory activities, whereas retinol palmitate exhibited significant but weak activity for umu C gene expression in tester bacteria induced by 3-amino-3,4-dimethyl-5H-pyrido[4.3-b]indol (Trp-P-1) in the presence of hepatic metabolizing enzymes (S9 mixture). Carotenoids having provitamin A activity (beta-carotene and canthaxanthin) exhibited moderate suppressive effects on the same experimental system. The ranks of suppressive activities were retinol > retinol acetate > retinoic acid > canthaxanthin > beta-carotene > retinol palmitate and their doses for inhibition by 50% (ID50) were estimated to be 1.2 x 10(-7), 3.0 x 10(-7), 5.4 x 10(-7), 1.5 x 10(-6), 4.0 x 10(-5) and 6.0 x 10(-5) M, respectively. However, they did not cause significant inhibition on umu C gene expression induced by direct-acting mutagen (adriamycin or mitomycin C) in the absence of S9 mixture. Inhibition of umu gene expression appears to be due to inhibition of P450-mediated metabolic activation of the heterocyclic amine Trp-P-1. Ascorbic acid (vitamin C) showed weak but significant suppressive activity at high-dose concentrations (3 x 10(-6) - 10(-4)M). However, alpha-tocopherol did not exhibit significant suppression at all dose concentrations. The significance of the experimental results is discussed from the viewpoint of the chemoprevention against genotoxicity associated with carcinogenesis.

D-erythroascorbic acid: Its preparations, chemistry, and metabolism (fungi and plants)

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

Loewus, F.A.; Seib, P.A.

1991-01-01

The origin of oxalate in plants has received considerable attention and glycolate metabolism has been generally regarded as a prime precursor candidate although studies on the metabolism of L-ascorbic acid single out that plant constituent as well. Experiments with oxalate-accumulating plants that contain little or no tartaric acid revealed the presence of a comparable L-ascorbic acid metabolism with the exception that the cleavage products were oxalic acid and L-threonic acid or products of L-threonic acid metabolism. A reasonable mechanism for cleavage of L-ascorbic acid at the endiolic bond is found in studies on the photooxygenation of L-ascorbic acid. Presumably, analogsmore » of L-ascorbic acid that differ only in the substituent at C4 also form a hydroperoxide in the presence of alkaline hydrogen peroxide and subsequently yield oxalic acid and the corresponding aldonic acid or its lactone. We became interested in such a possibility when we discovered that L-ascorbic acid was rare or absent in certain yeasts and fungi whereas a L-ascorbic acid analog, D-glycero-pent-2-enono- 1,4-lactone (D-erythroascorbic acid), was present. It has long been known that oxalate occurs in yeasts and fungi and its production plays a role in plant pathogenesis. As to the biosynthetic origin of fungal oxalic acid there is little information although it is generally assumed that oxaloacetate or possibly, glycolate, might be that precursor.« less

D-erythroascorbic acid: Its preparations, chemistry, and metabolism (fungi and plants). Final report

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

Loewus, F.A.; Seib, P.A.

1991-12-31

The origin of oxalate in plants has received considerable attention and glycolate metabolism has been generally regarded as a prime precursor candidate although studies on the metabolism of L-ascorbic acid single out that plant constituent as well. Experiments with oxalate-accumulating plants that contain little or no tartaric acid revealed the presence of a comparable L-ascorbic acid metabolism with the exception that the cleavage products were oxalic acid and L-threonic acid or products of L-threonic acid metabolism. A reasonable mechanism for cleavage of L-ascorbic acid at the endiolic bond is found in studies on the photooxygenation of L-ascorbic acid. Presumably, analogsmore » of L-ascorbic acid that differ only in the substituent at C4 also form a hydroperoxide in the presence of alkaline hydrogen peroxide and subsequently yield oxalic acid and the corresponding aldonic acid or its lactone. We became interested in such a possibility when we discovered that L-ascorbic acid was rare or absent in certain yeasts and fungi whereas a L-ascorbic acid analog, D-glycero-pent-2-enono- 1,4-lactone (D-erythroascorbic acid), was present. It has long been known that oxalate occurs in yeasts and fungi and its production plays a role in plant pathogenesis. As to the biosynthetic origin of fungal oxalic acid there is little information although it is generally assumed that oxaloacetate or possibly, glycolate, might be that precursor.« less

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

ESR study of photoinduced free radicals by visible light in hair and the effects of ascorbic acid (vitamin C).

PubMed

Chikvaidze, E; Khachatryan, I

2011-08-01

The ESR spectra of melanin's free radicals in natural black and red hair have been investigated. It is shown that the ESR spectrum of black hair is slightly asymmetric singlet with g=2.0037 and ΔH=0.5 mTl. The ESR spectrum of red hair with g=2.0053 differs from the spectrum of black hair. Using the method of saturation was shown that ESR spectrum of red hair represents a superposition of two signals: a singlet, relating to the black hair, and a triplet from red hair's pheomelanin. Under the influence of visible light (blue with λ(max) =450 nm, green with λ(max) =510 nm and red with λ(max) =650 nm) in both types of hair (black and red), the photoinduced free radicals appear, which indicates an increase in the intensity of already existing ESR spectrum of hair. It should be noted that the ESR spectra of red hair from various donors are different. The antioxidant ascorbic acid (vitamin C) has the different effect on the photoinduced free radicals. In particular, in the case of black hair, the concentration of photoinduced free radicals is slightly reduced, whereas in red hair, the disappearance of the triplet in the spectrum is observed, and at the same time, the spectrum becomes a singlet, the intensity of which increases sharply. It is assumed that the antioxidants, effective for black hair, may be ineffective for red hair and vice versa. Therefore, in each, specific case is necessary to investigate the effectiveness of an antioxidant separately. © 2011 The Authors. ICS © 2011 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Vitamin C content in sea buckthorn berries (Hippophaë rhamnoides L. ssp. rhamnoides) and related products: a kinetic study on storage stability and the determination of processing effects.

PubMed

Gutzeit, D; Baleanu, G; Winterhalter, P; Jerz, G

2008-11-01

The primary vitamin in sea buckthorn berries is vitamin C containing values of approximately 400 mg/100 g. Processing effects were investigated during juice and concentrate production from sea buckthorn berries (Hippophaë rhamnoides) and storage stability of juices was determined for up to 7 d using berries and juices from 2 different growing areas. During industrial juice production the technological processing of the berries caused a loss of about 5% to 11% total ascorbic acid (TAA) in the generated juice. The production of the concentrated juice resulted in 50% depletion of TAA. Sea buckthorn berries and juice were stored at 6, 25, and 40 degrees C for up to 7 d to investigate the temperature effects on TAA during storage. Analysis of kinetic data suggested that the degradation follows a 1st-order model. The results of the experiments showed that storage of sea buckthorn juices for 7 d at cold temperature (6 degrees C) already resulted in a degradation of TAA of about 11% to 12%.

[Vitamin C+sodium bicarbonate versus sodium bicarbonate alone in preventing contrast-induced nephropathy].

PubMed

Laroussi, L; Triki, M; Ibn Elhaj, Z; Ben Halima, A; Boukhris, M; Ben Amara, W; Keskes, H; Kraiem, S; Lahidheb, D; Marrakchi, S; Kammoun, I; Addad, F; Kachboura, S

2017-09-01

Contrast-induced nephropathy (CIN) is a common and severe complication in interventional cardiology. The aim of our study was to compare the incidence of contrast-induced nephropathy in two accelerated hydration protocols: the first one by the serum bicarbonate and the second combining the serum bicarbonate and oral vitamin C. This is a multicenter prospective, randomized study conducted between October 2012 and May 2013, including 160 patients. The mean age of our study population was 60.8±9.3 years (36-83 years). The two study groups were comparable in terms of cardiovascular risk factors, concomitant medication, and baseline serum creatinine. The CIN incidence was 6.3% in the vitamin C group and 10% in the control group (P=0.38). No significant difference was observed in terms of CIN incidence between the different subgroups analyzed. According to our study, ascorbic acid administered orally as part of an accelerated hydration protocol does not reduce the incidence of CIN. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

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.

Nutritional and anti-nutritional potential of three accessions of itching bean (Mucuna pruriens (L.) DC var. pruriens): an under-utilized tribal pulse.

PubMed

Kala, Balasubiramanian Kamatchi; Mohan, Veerabahu Ramasamy

2010-08-01

Three accessions of the under-utilized legume itching bean (Mucuna pruriens var. pruriens) were analysed for proximate composition, mineral profiles, vitamins (niacin and ascorbic acid), fatty acid profiles, amino acid profiles of total seed protein, in vitro protein digestibility and certain anti-nutritional factors. All three accessions of M. pruriens var. pruriens contained higher amounts of crude protein and crude lipid when compared with most of the commonly consumed pulses. The fatty acid profiles revealed that the seed lipids contained a higher concentration of palmitic acid and linoleic acids. Amino acid profiles of M. pruriens var. pruriens revealed that the seed protein contained relatively higher levels of certain essential amino acids compared with the FAO/WHO requirement pattern. The investigated seeds are rich in minerals such as potassium, calcium, magnesium, phosphorus, iron and manganese. Anti nutritional substances such as total free phenolics, tannins, 3,4-dihydroxyphenylalanine, phytic acid, hydrogen cyanide, trypsin inhibitor activity, oligosaccharides and phytohaemagglutinating activity were investigated. The anti-nutritional fatty acid, behenic acid, also was detected in the present study.

Effects of Pre-Converted Nitrite from Red Beet and Ascorbic Acid on Quality Characteristics in Meat Emulsions

PubMed Central

Kim, Hyun-Wook; Hwang, Ko-Eun

2017-01-01

We investigated the effects of fermented red beet extract and ascorbic acid on color development in meat emulsions. The pH of meat emulsions containing red beet extract decreased with an increase in the amount of extract added. The redness of the treated meat emulsions was higher than that of the control with no added nitrite or fermented red beet extract (p<0.05), though the redness of the meat emulsions treated with fermented red beet extract only was lower than in that treated with both fermented red beet extract and ascorbic acid (p<0.05). The highest VBN, TBARS, and total viable count values were observed in the control, and these values in the meat emulsions treated with fermented red beet extract were higher than in that treated with both fermented red beet extract and ascorbic acid (p<0.05). E. coli and coliform bacteria were not found in any of the meat emulsions tested. Treatment T2, containing nitrite and ascorbic acid, had the highest overall acceptability score (p<0.05); however, there was no significant difference between the T2 treatment and the T6 treatment, which contained 10% pre-converted nitrite from red beet extract and 0.05% ascorbic acid (p>0.05). The residual nitrite content of the meat emulsions treated with ascorbic acid was lower than in those treated without ascorbic acid (p<0.05). Thus, the combination of fermented red beet extract and ascorbic acid could be a viable alternative to synthetic nitrite for the stability of color development in meat emulsions. PMID:28515652

Effect of different levels of an ascorbic acid and tea mixture on nonheme iron absorption from a typical Tunisian meal fed to healthy rats.

PubMed

Hamdauoui, M; Doghri, T; Tritar, B

1995-01-01

The aim of our study was to evaluate the bioavailability of iron from a typical Tunisian meal 'couscous' provided to healthy rats with or without appropriate mixtures of tea plus ascorbic acid and to search for the optimal amount of ascorbic acid able to overcome the inhibitory effect of tea prepared under realistic Tunisian circumstances. Our findings show that a tea decoction (100 mg/ml) reduced nonheme iron absorption from couscous by 50% (16.5 vs. 33.1%; p < 0.01). In contrast, administration of 20 mg ascorbic acid increased nonheme iron absorption from couscous by more than 100% (66.8 vs. 33.1%; p < 0.001). Administration of ascorbic acid (20 mg) in a tea decoction (100 mg/ml) completely counteracted the inhibiting effect of tea and significantly improved the nonheme iron absorption from couscous (34 vs. 33% in the control group; NS). The same effect was shown when 10 mg ascorbic acid was added to the tea decoction; however, 5 mg ascorbic acid was not able to overcome the inhibitory effect of tea on nonheme iron absorption from couscous (33.1 vs. 19.4%; p < 0.01). Our findings demonstrate that a molar ratio of ascorbic acid and tea equal or superior to 0.25 or 0.50 is necessary to overcome the inhibitory effect in rats of tea prepared under Tunisian circumstances. In relation to human nutrition, for Tunisians who regularly drink tea, we suggest a much greater amount of ascorbic acid than that normally recommended for normal subjects.

Effects of Pre-Converted Nitrite from Red Beet and Ascorbic Acid on Quality Characteristics in Meat Emulsions.

PubMed

Choi, Yun-Sang; Kim, Tae-Kyung; Jeon, Ki-Hong; Park, Jong-Dae; Kim, Hyun-Wook; Hwang, Ko-Eun; Kim, Young-Boong

2017-01-01

We investigated the effects of fermented red beet extract and ascorbic acid on color development in meat emulsions. The pH of meat emulsions containing red beet extract decreased with an increase in the amount of extract added. The redness of the treated meat emulsions was higher than that of the control with no added nitrite or fermented red beet extract ( p <0.05), though the redness of the meat emulsions treated with fermented red beet extract only was lower than in that treated with both fermented red beet extract and ascorbic acid ( p <0.05). The highest VBN, TBARS, and total viable count values were observed in the control, and these values in the meat emulsions treated with fermented red beet extract were higher than in that treated with both fermented red beet extract and ascorbic acid ( p <0.05). E. coli and coliform bacteria were not found in any of the meat emulsions tested. Treatment T2, containing nitrite and ascorbic acid, had the highest overall acceptability score ( p <0.05); however, there was no significant difference between the T2 treatment and the T6 treatment, which contained 10% pre-converted nitrite from red beet extract and 0.05% ascorbic acid ( p >0.05). The residual nitrite content of the meat emulsions treated with ascorbic acid was lower than in those treated without ascorbic acid ( p <0.05). Thus, the combination of fermented red beet extract and ascorbic acid could be a viable alternative to synthetic nitrite for the stability of color development in meat emulsions.

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

[Sufficiency with water-soluble vitamins and state of bone in pregnant women].

PubMed

Vrzhesinskaya, O A; Pereverzeva, O G; Gmoshinskaya, M V; Kodentsova, V M; Safronova, A I; Korosteleva, M M; Aleshina, I V; Fandeeva, T A

2015-01-01

Vitamin status and bone strength have been estimated in 91 pregnant women (29.3 ± 4.6 years old) from Moscow by non-invasive methods. Sufficiency with vitamins C, B2, B6 has been evaluated by morning urinary excretion of ascorbic acid, riboflavin and 4-piridoxic acid determined by visual titration and fluorimetric methods. The rate of bone resorption has been measured by the ratio of urinary calcium and creatinine, determined by complexometric titration and spectrophotometrically. The study of the bone strength has been conducted using an ultrasonic densitometer (the speed of the ultrasonic waves along the cortical layer). The lack of vitamin C was found in 20.4% .of the women surveyed, vitamin B2--in 27.4%. Vitamin B6 deficiency was detected most frequently (90%). Excretion of vitamins B2 and B6 in women in the third trimester of pregnancy was lower as compared with the women in the first and second trimester. In 53.3% of the women surveyed an increase in urinary excretion of calcium per creatinine has been observed. Excretion of group B vitamins (especially vitamin B6, 1.75 fold, p < 0.05) in women taking vitamin supplements was higher compared to non-taking vitamins that indicates the better sufficiency of the organism with these vitamins. Among women who took vitamin complexes, inadequate supply with water-soluble vitamins C, B2 and B6 was detected less frequently (the difference was significant for vitamin B2) than among women who did not intake vitamin complexes (in 11.9, 27.7 and 42.4% vs 16.1, 54.8 and 48.8 %). The rate of bone resorption (Ca/creatinine) in women taking vitamins was smaller (0.19 ± 0.09 vs 0.24 ± 0.14, p > 0.05). Ca/creatinine ratio was within normal range in 40% of women who intake vitamins, while in women not taking vitamins--only in 22.2%; this value exceeded the upper limit of norm in the rest. The strength of bone was broken in women in the second and third trimester of pregnancy, having worse supply of vitamins. The percentage of agreement of the results of osteopenia diagnosis assessment (ultrasound densitometry and urinary Ca/creatinine) was 42.2%. Thus, the conclusion has been confirmed that the evaluation of the status of bone is possible only basing on the results of determination of several parameters.

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...

Aqueous humour and ultraviolet radiation.

PubMed

Ringvold, A

1980-01-01

Studies on the ultraviolet ray absorption in the aqueous humour of rabbit, cat, monkey, guinea pig, and rat showed marked species differences. In the rabbit aqueous the ascorbic acid, the proteins, and some amino acids (tyrosine, phenylalanine, cystine, and tryptophane) are together responsible for the total absorption, and a very great part of it refers to the ascorbic acid content. Accordingly, species with significant amounts of ascorbic acid in the aqueous (monkey, rabbit, guinea pig) have a greater absorption capacity towards ultraviolet radiation than species (cat, rat) lacking this substance. This effect of the ascorbic acid may contribute in protecting the lens against the most biotoxic ultraviolet rays. It seems that the ascorbic acid concentration is highest in the aqueous of typical day animals and lowest in species being active in the dark, indicating a correlation between the aqueous' ascorbic acid level and the quantity of incident light on the eye. The possible significance of changed aqueous ultraviolet ray absorption in the pathogenesis of human cataract development is discussed.

Ameliorative Effect of Chronic Supplementation of Protocatechuic Acid Alone and in Combination with Ascorbic Acid in Aniline Hydrochloride Induced Spleen Toxicity in Rats.

PubMed

Khairnar, Upasana; Upaganlawar, Aman; Upasani, Chandrashekhar

2016-01-01

Background. Present study was designed to evaluate the protective effects of protocatechuic acid alone and in combination with ascorbic acid in aniline hydrochloride induced spleen toxicity in rats. Materials and Methods. Male Wistar rats of either sex (200-250 g) were used and divided into different groups. Spleen toxicity was induced by aniline hydrochloride (100 ppm) in drinking water for a period of 28 days. Treatment group received protocatechuic acid (40 mg/kg/day, p.o.), ascorbic acid (40 mg/kg/day, p.o.), and combination of protocatechuic acid (20 mg/kg/day, p.o.) and ascorbic acid (20 mg/kg/day, p.o.) followed by aniline hydrochloride. At the end of treatment period serum and tissue parameters were evaluated. Result. Rats supplemented with aniline hydrochloride showed a significant alteration in body weight, spleen weight, feed consumption, water intake, hematological parameters (haemoglobin content, red blood cells, white blood cells, and total iron content), tissue parameters (lipid peroxidation, reduced glutathione, and nitric oxide content), and membrane bound phosphatase (ATPase) compared to control group. Histopathology of aniline hydrochloride induced spleen showed significant damage compared to control rats. Treatment with protocatechuic acid along with ascorbic acid showed better protection as compared to protocatechuic acid or ascorbic acid alone in aniline hydrochloride induced spleen toxicity. Conclusion. Treatment with protocatechuic acid and ascorbic acid in combination showed significant protection in aniline hydrochloride induced splenic toxicity in rats.

Dietary ascorbic acid and subsequent change in body weight and waist circumference: associations may depend on genetic predisposition to obesity - a prospective study of three independent cohorts

PubMed Central

2014-01-01

Background Cross-sectional data suggests that a low level of plasma ascorbic acid positively associates with both Body Mass Index (BMI) and Waist Circumference (WC). This leads to questions about a possible relationship between dietary intake of ascorbic acid and subsequent changes in anthropometry, and whether such associations may depend on genetic predisposition to obesity. Hence, we examined whether dietary ascorbic acid, possibly in interaction with the genetic predisposition to a high BMI, WC or waist-hip ratio adjusted for BMI (WHR), associates with subsequent annual changes in weight (∆BW) and waist circumference (∆WC). Methods A total of 7,569 participants’ from MONICA, the Diet Cancer and Health study and the INTER99 study were included in the study. We combined 50 obesity associated single nucleotide polymorphisms (SNPs) in four genetic scores: a score of all SNPs and a score for each of the traits (BMI, WC and WHR) with which the SNPs associate. Linear regression was used to examine the association between ascorbic acid intake and ΔBW or ΔWC. SNP-score × ascorbic acid interactions were examined by adding product terms to the models. Results We found no significant associations between dietary ascorbic acid and ∆BW or ∆WC. Regarding SNP-score × ascorbic acid interactions, each additional risk allele of the 14 WHR associated SNPs associated with a ∆WC of 0.039 cm/year (P = 0.02, 95% CI: 0.005 to 0.073) per 100 mg/day higher ascorbic acid intake. However, the association to ∆WC only remained borderline significant after adjustment for ∆BW. Conclusion In general, our study does not support an association between dietary ascorbic acid and ∆BW or ∆WC, but a diet with a high content of ascorbic acid may be weakly associated to higher WC gain among people who are genetically predisposed to a high WHR. However, given the quite limited association any public health relevance is questionable. PMID:24886192

Vulnerable atherosclerotic plaque morphology in apolipoprotein E-deficient mice unable to make ascorbic Acid.

PubMed

Nakata, Yukiko; Maeda, Nobuyo

2002-03-26

Oxidative stress is thought to play an important role in atherogenesis, suggesting that antioxidants could prevent coronary artery disease. However, the efficacy of vitamin C in reducing atherosclerosis is debatable in humans and has not been tested rigorously in animals. Gulo(-/-)Apoe(-/-) mice were used to test a hypothesis that chronic vitamin C deficiency enhances the initiation and development of atherosclerosis. These mice are dependent on dietary vitamin C because of the lack of L-gulonolactone-gamma-oxidase and are prone to develop atherosclerosis because of lacking apolipoprotein E. Beginning at 6 weeks of age, the Gulo(-/-)Apoe(-/-) mice were fed regular chow or Western-type diets containing high fat and supplemented with either 0.033 g or 3.3 g/L of vitamin C in their drinking water. This regimen produced mice with chronically low vitamin C (average 1.5 microg/mL in plasma) or high vitamin C (average 10 to 30 microg/mL in plasma). Morphometric analysis showed that within each sex, age, and diet group, the sizes of the atherosclerotic plaques were not different between low vitamin C mice and high vitamin C mice. However, advanced plaques in the low vitamin C mice had significantly reduced amounts of Sirius red-staining collagen (36.4+/-2.2% versus 54.8+/-2.3%, P<0.0001), larger necrotic cores within the plaques, and reduced fibroproliferation and neovascularization in the aortic adventitia. Chronic vitamin C deficiency does not influence the initiation or progression of atherosclerotic plaques but severely compromises collagen deposition and induces a type of plaque morphology that is potentially vulnerable to rupture.

Improvement of transgenic cloning efficiencies by culturing recipient oocytes and donor cells with antioxidant vitamins in cattle.

PubMed

Wongsrikeao, Pimprapar; Nagai, Takashi; Agung, Budiyanto; Taniguchi, Masayasu; Kunishi, Miho; Suto, Shizuyo; Otoi, Takeshige

2007-06-01

The present study was conducted to investigate effects of antioxidants during maturation culture of recipient oocytes and/or culture of gene-transfected donor cells on the meiotic competence of recipient oocytes, and the developmental competence and quality of the reconstructed embryos after nuclear transfer (NT) in cattle. Gene-transfected donor cells had negative effects on the proportions of blastocyst formation, total cell numbers, and DNA fragmentation indices of reconstructed embryos. Supplementation of either vitamin E (alpha-tocopherol: 100 microM) or vitamin C (ascorbic acid: 100 microM) during maturation culture significantly enhanced the cytoplasmic maturation of oocytes and subsequent development of embryos reconstructed with the oocytes and gene-transfected donor cells, but did not have synergistic effects. The supplementation of vitamin E during maturation culture of recipient oocytes increased the proportions of fusion and blastocyst formation of gene-transfected NT embryos, in which the proportions were similar to those of nontransfected NT embryos. When the gene-transfected donor cells that had been cultured with 0, 50, or 100 microM of vitamin E were transferred into recipient oocytes matured with vitamin E (100 microM), 50 microM of vitamin E increased the proportion of blastocyst formation and reduced the index of DNA fragmentation of blastocysts. In conclusion, gene-transfected donor cells have negatively influenced the NT outcome. Supplementation of vitamin E during both recipient oocyte maturation and donor cell culture enhanced the blastocyst formation and efficiently blocked DNA damage in transgenic NT embryos. (c) 2006 Wiley-Liss, Inc.

Role of intracellular Ca2+ signal in the ascorbate-induced apoptosis in a human hepatoma cell line.

PubMed

Lee, Yong Soo

2004-12-01

Although ascorbate (vitamin C) has been shown to have anti-cancer actions, its effect on human hepatoma cells has not yet been investigated, and thus, the exact mechanism of this action is not fully understood. In this study, the mechanism by which ascorbate induces apoptosis using HepG2 human hepatoblastoma cells is investigated. Ascorbate induced apoptotic cell death in a dose-dependent manner in the cells, was assessed through flow cytometric analysis. Contrary to expectation, ascorbate did not alter the cellular redox status, and treatment with antioxidants (N-acetyl cysteine and N,N-diphenyl-p-phenylenediamine) had no influence on the ascorbate-induced apoptosis. However, ascorbate induced a rapid and sustained increase in intracellular Ca2+ concentration. EGTA, an extracellular Ca2+ chelator did not significantly alter the ascorbate-induced intracellular Ca2+ increase and apoptosis, whereas dantrolene, an intracellular Ca2+ release blocker, completely blocked these actions of ascorbate. In addition, phospholipase C (PLC) inhibitors (U-73122 and manoalide) significantly suppressed the intracellular Ca2+ release and apoptosis induced by ascorbate. Collectively, these results suggest that ascorbate induced apoptosis without changes in the cellular redox status in HepG2 cells, and that the PLC-coupled intracellular Ca2+ release mechanism may mediate ascorbate-induced apoptosis.

Consequences of the Combined α-tocopherol, Ascorbic Acid and α-lipoic Acid on the Glutathione, Cholesterol and Fatty Acid Composition in Muscle and Liver of Diabetic Rats

PubMed Central

YILMAZ, Okkes; ERSAN, Yasemin; Dilek OZSAHIN, Ayse; Ihsan OZTURK, Ali; OZKAN, Yusuf

2013-01-01

Objective(s): Our objective was to evaluate the effects of a triple antioxidant combination [α-tocopherol (AT), ascorbic acid (AA) and α-lipoic acid (LA); AT+AA+LA] on the cholesterol and glutathione levels, and the fatty acid composition of liver and muscle tissues in diabetic rats. Materials and Methods: Forty-three Wistar rats were randomly divided into five groups. The first group was used as a control. The second, third and fourth groups received STZ (45 mg/kg) in citrate buffer. The fourth and fifth groups were injected with intraperitoneal (IP) 50 mg/kg DL-AT and 50 mg /kg DL-LA four times per week and received water-soluble vitamin C (50 mg/kg) in their drinking water for a period of six weeks. Results: Liver cholesterol levels in the AT+AA+LA group were lower than the control (P<0.05). Glutathione level was lower in D-2 (P<0.05) and were higher in D+AT+AA+LA and AT+AA+LA groups than the control groups (P≤ 0.05). The muscle cholesterol levels in the D-1 and D+AT+AA+LA groups were higher than the control group (P≤ 0.05). The levels of oleic acid were higher in the D-1 group and lower in the D-2 group (P<0.001). The arachidonic acid level in the D-1 and D-2 groups were lower (P<0.05), and higher in the D+AT+AA+LA group. Conclusion: Our results revealed that glutathione levels and the Stearoyl CoA Desaturase enzyme products in liver tissues of diabetic and non-diabetic rats were increased by triple antioxidant mixture. PMID:24298385

Consequences of the Combined α-tocopherol, Ascorbic Acid and α-lipoic Acid on the Glutathione, Cholesterol and Fatty Acid Composition in Muscle and Liver of Diabetic Rats.

PubMed

Yilmaz, Okkes; Ersan, Yasemin; Dilek Ozsahin, Ayse; Ihsan Ozturk, Ali; Ozkan, Yusuf

2013-02-01

Our objective was to evaluate the effects of a triple antioxidant combination [α-tocopherol (AT), ascorbic acid (AA) and α-lipoic acid (LA); AT+AA+LA] on the cholesterol and glutathione levels, and the fatty acid composition of liver and muscle tissues in diabetic rats. Forty-three Wistar rats were randomly divided into five groups. The first group was used as a control. The second, third and fourth groups received STZ (45 mg/kg) in citrate buffer. The fourth and fifth groups were injected with intraperitoneal (IP) 50 mg/kg DL-AT and 50 mg /kg DL-LA four times per week and received water-soluble vitamin C (50 mg/kg) in their drinking water for a period of six weeks. Liver cholesterol levels in the AT+AA+LA group were lower than the control (P<0.05). Glutathione level was lower in D-2 (P<0.05) and were higher in D+AT+AA+LA and AT+AA+LA groups than the control groups (P≤ 0.05). The muscle cholesterol levels in the D-1 and D+AT+AA+LA groups were higher than the control group (P≤ 0.05). The levels of oleic acid were higher in the D-1 group and lower in the D-2 group (P<0.001). The arachidonic acid level in the D-1 and D-2 groups were lower (P<0.05), and higher in the D+AT+AA+LA group. Our results revealed that glutathione levels and the Stearoyl CoA Desaturase enzyme products in liver tissues of diabetic and non-diabetic rats were increased by triple antioxidant mixture.

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

Release of enzymes from lysosomes by irradiation and the relation of lipid peroxide formation to enzyme release

PubMed Central

Wills, E. D.; Wilkinson, A. E.

1966-01-01

1. Acid phosphatase, cathepsin and β-glucuronidase are released from rat-liver lysosomes by irradiation in vitro. Enzyme release is detectable after a dose of 1krad and increases with dose up to 100krads. 2. Maximum radiation effects were observed when the lysosomes were kept for 20hr. at 4° or 20° after irradiation. 3. An atmosphere of nitrogen considerably decreases enzyme release from lysosomes. 4. Enzyme release is enhanced by ascorbic acid and decreased by vitamin E. 5. Irradiation causes formation of lipid peroxides in lysosomes, and enzyme release increases with lipid peroxide formation. 6. It is suggested that lipid peroxide formation leads to rupture of the lysosome membrane and allows release of the contained hydrolytic enzymes. PMID:5964962

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.

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.

Free radicals mediate postshock contractile impairment in cardiomyocytes.

PubMed

Tsai, Min-Shan; Sun, Shijie; Tang, Wanchun; Ristagno, Giuseppe; Chen, Wen-Jone; Weil, Max Harry

2008-12-01

Previous studies demonstrated myocardial dysfunction after electrical shock and indicated it may be related to free radicals. Whether the free radicals are generated after electrical shock has not been documented at the cellular level. This study was to investigate whether electrical shock generates intracellular free radicals inside cardiomyocytes and to evaluate whether reducing intracellular free radicals by pretreatment of ascorbic acid would reduce the contractile dysfunction after electrical shock. Randomized prospective animal study. University affiliated research laboratory. Sprague-Dawley rats. Cardiomyocytes isolated from adult male rats were divided into four groups: (1) electrical shock alone; (2) electrical shock pretreated with ascorbic acid; (3) pretreated with ascorbic acid alone; and (4) control. Ascorbic acid (0.2 mM) was administrated in the perfusate of the ascorbic acid + electrical shock and ascorbic acid groups. A 2-J electrical shock was delivered to the electrical shock and ascorbic acid + electrical shock groups. DCFH-DA-loaded cardiomyocytes showed increased intracellular free radicals after electrical shock. The contractions and Ca2+ transients were recorded optically with fura-2 loading. Within 4 mins after electrical shock in the electrical shock group, the length shortening decreased from 8.4% +/- 2.5% to 5.6% +/- 3.4% (p = 0.000) and the Ca2+ transient decreased from 1.15 +/- 0.13 au to 1.08 +/- 0.1 au (p = 0.038). Compared with control, a significant difference in length shortening (p = 0.001) but not Ca2+ transient (p = 0.052) was noted. In the presence of ascorbic acid, electrical shock did not affect length shortening and Ca2+ transient. Electrical shock generates free radicals inside the cardiomyocyte, and causes contractile impairment and associated decrease of Ca transient. Administering ascorbic acid may improve such damage by eliminating free radicals.

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 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

Effect of Pullulan Coating on Postharvest Quality and Shelf-Life of Highbush Blueberry (Vaccinium corymbosum L.).

PubMed

Kraśniewska, Karolina; Ścibisz, Iwona; Gniewosz, Małgorzata; Mitek, Marta; Pobiega, Katarzyna; Cendrowski, Andrzej

2017-08-18

Fruits form an important part of a healthy human diet as they contain many ingredients with proven pro-health effects such as vitamins, phenolic compounds, organic acids, fiber, and minerals. The purpose of this work was to evaluate the effect of pullulan coating on the quality and shelf life of highbush blueberry during storage. General appearance, weight loss, dry matter, soluble solid content, reducing sugars, content of L-ascorbic acid, phenolic compounds (total phenolics, phenolics acids and anthocyanins) were determined in uncoated and coated blueberries fruits. The microbiological efficiency of pullulan coating was also evaluated. All parameters were monitored during storage at 4 °C and 16 °C by 28 and 14 days, respectively. The study showed that pullulan coating protects perishable food products especially susceptible to mechanical injury including fruits such as blueberries. Pullulan acts as a barrier that minimizes respiration rate, delaying deterioration and controlling microbial growth.

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...

Effect of ascorbic acid postharvest treatment on enzymatic browning, phenolics and antioxidant capacity of stored mung bean sprouts.

PubMed

Sikora, Małgorzata; Świeca, Michał

2018-01-15

Enzymatic browning limits the postharvest life of minimally processed foods, thus the study selected the optimal inhibitors of polyphenol oxidase (PPO) and evaluated their effect on enzymatic browning, phenolics and antioxidant capacity of stored mung bean sprouts. The sprouts treated with 2mM and 20mM ascorbic acid had a lowered PPO activity; compared to the control by 51% and 60%, respectively. The inhibition was reflected in a significant decrease in enzymatic browning. The sprouts treated with 20mM ascorbic acid had 22% and 23% higher phenolic content after 3 and 7days of storage, respectively. Both storage and ascorbic acid treatment increased potential bioaccessibility of phenolics. Generally, there was no effect of the treatments on the antioxidant capacity; however, a significant increase in the reducing potential was determined for the sprouts washed with 20mM ascorbic acid. In conclusion, ascorbic acid treatments may improve consumer quality of stored sprouts. Copyright © 2017 Elsevier Ltd. All rights reserved.

The co-pigmentation of anthocyanin isolated from mangosteen pericarp (Garcinia Mangostana L.) as Natural Dye for Dye- Sensitized Solar Cells (DSSC)

NASA Astrophysics Data System (ADS)

Munawaroh, H.; adillah, G. F.; Saputri, L. N. M. Z.; Hanif, Q. A.; Hidayat, R.; Wahyuningsih, S.

2016-02-01

Study of color stability of anthocyanin from extract mangosteen pericarp (Garcinia mangostana L.) with co-pigmentation method has been conducted. Malic acid and ascorbic acid used as a co-pigment to stabilize the anthocyanin structure through formation of new binding between anthocyanin. Anthocyanin from mangosteen pericarp were isolated by several steps, including maceration, extraction, and Thin Layer Chromatography (TLC). The anthocyanin separation was conducted by TLC, while the identification of functional groups of those compound, were used FTIR (Fourier Transform Infrared Spectroscopy) for spectra analysis. Ultraviolet- visible absorption spectra have represented differences absorbance and color intensity in various pH. Copigmentation with malic acid and ascorbic acid in many composition and temperature were also well described. Meanwhile, anthocyanin-malic acid and anthocyanin-ascorbic acid have color retention higher than that of pure anthocyanin. Maximum color retention has been achieved at a ratio of 1:3 and 1:5 for ascorbic acid and malic acid, respectively. Therefore, the addition of ascorbic acid and malic acid as a copigment shows the ability to protect color retention of anthocyanin (mangosteen pericarp) from degradation process. The better efficiency of DSSC (η) have been achieved, whereas n of controlled anthocyanin, anthocyanin-ascorbic acid, and anthocyanin-malic acid were 0,1996%, 0,2922%, 0,3029%, respectively.

Synergistic cytotoxic action of vitamin C and vitamin K3.

PubMed

Zhang, W; Negoro, T; Satoh, K; Jiang, Y; Hashimoto, K; Kikuchi, H; Nishikawa, H; Miyata, T; Yamamoto, Y; Nakano, K; Yasumoto, E; Nakayachi, T; Mineno, K; Satoh, T; Sakagami, H

2001-01-01

We investigated the combination effect of sodium ascorbate (vitamin C) and menadione (vitamin K3) on the viability of various cultured cells. Human oral squamous cell carcinoma (HSC-2, HSC-3) and human promyelocytic leukemia (HL-60) cells were more sensitive to these vitamins as compared to normal cells (human gingival fibroblast HGF, human periodontal ligament fibroblast HPLF, human pulp cell HPC). The combination of vitamin C and vitamin K3 produced synergistic cytotoxicity against all these 6 cell lines. Treatment with vitamin C or vitamin K3, or their combination, induced internucleosomal DNA fragmentation only in HL-60 cells, but not in the oral tumor cell lines (HSC-2, HSC-3, HSG). ESR spectroscopy showed that vitamins C and K3 produce radicals under alkaline conditions and that the combination of these two vitamins synergistically enhanced their respective radical intensities.

Carotenoids, polyphenols and micronutrient profiles of Brassica oleraceae and plum varieties and their contribution to measures of total antioxidant capacity.

PubMed

Kaulmann, Anouk; Jonville, Marie-Caroline; Schneider, Yves-Jacques; Hoffmann, Lucien; Bohn, Torsten

2014-07-15

The consumption of phytochemicals such as carotenoids and polyphenols within whole fruits and vegetables has been associated with decreased incidence of various inflammation and oxidative stress related chronic diseases, which may be due to direct antioxidant effects, or indirect mechanisms such as affecting signal transduction/gene expression. Within the present study, we investigated the antioxidant composition of two major groups of vegetables and fruits, Brassica oleraceae and prunus spp., and estimated their contribution to antioxidant capacity. For this purpose, 17 plum and 27 Brassica varieties were collected in Luxembourg, and analysed for their individual polyphenol and carotenoid profile, vitamin C, dietary fibre, and minerals/trace elements, and their correlation with markers of antioxidant capacity (FRAP, ABTS, Folin-Ciocalteu). Total carotenoid and polyphenol content varied considerably between the different Brassica and plum varieties, with highest concentrations in the variety Kale (13.3 ± 0.58 mg/100g wet weight) and Cherry plum (1.96 ± 0.28 mg/100g) for carotenoids; and Kale (27.0 ± 0.91 mg/100g) and Kirks plum (185 ± 14 mg/100g) for polyphenols. In developed multiple linear-regression-models for Brassica, flavonoids, anthocyanins, lutein and vitamin C were found to be the best predictors of antioxidant capacity as assessed by FRAP (R(2)=0.832) and flavonoids, neochlorogenic acid and vitamin C as assessed by ABTS (R(2)=0.831); while for plums these were selenium, total sugars, chlorogenic acid and vitamin C (R(2)=0.853), and selenium, chlorogenic acid and flavonoids for FRAP (R(2)=0.711). When considering Brassica and plum consumption in Luxembourg, it is estimated that both contribute to an antioxidant intake equivalent to 26 and 6 mg per day of ascorbic acid equivalents, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

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).

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...

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.

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

Anemia Causes Hypoglycemia in Intensive Care Unit Patients Due to Error in Single-Channel Glucometers: Methods of Reducing Patient Risk

DTIC Science & Technology

2010-01-01

hematocrit, low oxygen tension, acetaminophen, uric acid , ascorbic acid , maltose, galactose, xy- lose, lactose, operator inexperience, age of strips, heat...Biomedical, Waltham, MA) that corrects for the effects of anemia, low oxygen tension, acetaminophen, uric acid , ascorbic acid , maltose, galactose, xylose, and...resulted in inappropriately high glucometer values (data not shown). The effects of interfering substances (acetaminophen, uric acid , ascorbic acid

Nitric Oxide in Plants: The Roles of Ascorbate and Hemoglobin

PubMed Central

Wang, Xiaoguang; Hargrove, Mark S.

2013-01-01

Ascorbic acid and hemoglobins have been linked to nitric oxide metabolism in plants. It has been hypothesized that ascorbic acid directly reduces plant hemoglobin in support of NO scavenging, producing nitrate and monodehydroascorbate. In this scenario, monodehydroascorbate reductase uses NADH to reduce monodehydroascorbate back to ascorbate to sustain the cycle. To test this hypothesis, rates of rice nonsymbiotic hemoglobin reduction by ascorbate were measured directly, in the presence and absence of purified rice monodehydroascorbate reductase and NADH. Solution NO scavenging was also measured methodically in the presence and absence of rice nonsymbiotic hemoglobin and monodehydroascorbate reductase, under hypoxic and normoxic conditions, in an effort to gauge the likelihood of these proteins affecting NO metabolism in plant tissues. Our results indicate that ascorbic acid slowly reduces rice nonsymbiotic hemoglobin at a rate identical to myoglobin reduction. The product of the reaction is monodehydroascorbate, which can be efficiently reduced back to ascorbate in the presence of monodehydroascorbate reductase and NADH. However, our NO scavenging results suggest that the direct reduction of plant hemoglobin by ascorbic acid is unlikely to serve as a significant factor in NO metabolism, even in the presence of monodehydroascorbate reductase. Finally, the possibility that the direct reaction of nitrite/nitrous acid and ascorbic acid produces NO was measured at various pH values mimicking hypoxic plant cells. Our results suggest that this reaction is a likely source of NO as the plant cell pH drops below 7, and as nitrite concentrations rise to mM levels during hypoxia. PMID:24376554

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...

Effect of dietary protein and hypervitaminosis A or C on tissue peroxidation and erythrocyte lysis of vitamin E deficiency.

PubMed

Jayanthi Bai, N; Sanjeev Kumar, P; George, T; Krishnamurthy, S

1982-01-01

Rats were maintained on a vitamin E free diet containing 20% safflower oil for a period of 12 weeks at two dietary protein levels, 20% and 10% casein. Enhanced in vitro tissue lipid peroxidation and lysis of erythrocytes were noticed at both the protein levels. A reduction in body mass and tissue weights were observed in both the protein groups but more so at 20% protein level. Feeding of retinyl palmitate (100 000 IU/100 g body weight) for 4 consecutive days to -E rats inhibited liver and kidney in vitro lipid peroxidation. Ascorbic acid (150 mg/100 g body weight) given orally for 5 days to -E rats inhibited liver brain and kidney in vitro peroxidation. Lysis of erythrocytes from -E rats was further increased by dosing with both the vitamins "A" and "C", the latter being more effective. The stromal enzymes acetyl choline esterase and ATPase were lowered, following the hemolysis profile of the erythrocytes from the different groups. Glutathione content of erythrocytes were unaffected except in -E +C group. In all groups the higher protein level (20%) produced greater lysis as compared to 10% level. It is concluded that 20% protein is more injurious in vitamin E deficiency simultaneously made hypervitaminosis A or C.

Lambda-cyhalothrin-induced biochemical and histopathological changes in the liver of rats: ameliorative effect of ascorbic acid.

PubMed

Fetoui, Hamadi; Garoui, El Mouldi; Zeghal, Najiba

2009-05-01

Pyrethroid pesticides were used preferably over organochlorines and organophosphates due to their high effectiveness, low toxicity to non-target organisms and easy biodegrability. It has widespread applications in agriculture through the world and in Tunisia. The present study investigates lambda-cyhalothrin (LTC) effects on biochemical parameters, hepatotoxicity and their attenuation by vitamin C. Male Wistar rats were randomly divided into three groups of seven each: a control group (C) and two treated groups during 3 weeks with LTC administrated either alone in drinking water for LTC group or coadministred with vitamin C for LTC+vit C group. Lactate deshydrogenase (LDH) activity was significantly increased in liver (+51%, p<0.001) and in plasma (+40%, p<0.001) compared to those of control group. A significant increase of malondialdehyde (MDA) levels in liver (+53%; p<0.001) associated with a decrease in antioxidants enzyme activities and reduced glutathione (GSH) content was observed in LTC group compared to controls. The administration of vitamin C to LTC+vit C group improved all parameters studied. We conclude that LTC induces oxidative stress and modifies biochemical parameters and histological aspects of liver. Administration of vitamin C alleviates the toxicity induced by this synthetic pyrethroid insecticide.

Chromium-picolinate induced ocular changes: Protective role of ascorbic acid.

PubMed

Mahmoud, Amany A; Karam, Sawsan H; Abdel-Wahhab, Mosaad A

2006-09-21

Chromium-picolinate (Cr-picolinate) is a popular nutritional supplement; however its safety has been questioned with regard to its ability to act as a clastogen. The aim of the present work was to evaluate the biochemical, histological and morphological changes in the cornea and lens following oral administration of Cr-picolinate and the possible protective effect of Vitamin C. Ninety male Sprague-Dawley rats were divided into five groups included the control group, the groups treated with Cr-picolinate (0.8 and 1.5 mg/100 g b.w.) alone or in combination with Vitamin C (0.5 mg/100 g b.w.) for 8 weeks. The results indicated that the high dose of Cr-picolinate induced a significant decrease in SOD, GSH, Na(+)-, K(+)-ATPase levels, and a significant increase in MDA level. Severe morphological and histological changes in the cornea and lens accompanied with a decrease in the total soluble protein of the lens homogenate and changes in the crystalline fractions in lens. Vitamin C supplementation succeeded to restore these changes to great extent. It could be concluded that consumption of Cr-picolinate for a long time induced several hazards to cornea and lens. Supplementation with extra amounts of Vitamin C may be useful to restrain the Cr-picolinate induced ocular changes.

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.

Molecular detection of exercise-induced free radicals following ascorbate prophylaxis in type 1 diabetes mellitus: a randomised controlled trial.

PubMed

Davison, G W; Ashton, T; George, L; Young, I S; McEneny, J; Davies, B; Jackson, S K; Peters, J R; Bailey, D M

2008-11-01

Patients with type 1 diabetes mellitus are more susceptible than healthy individuals to exercise-induced oxidative stress and vascular endothelial dysfunction, which has important implications for the progression of disease. Thus, in the present study, we designed a randomised double-blind, placebo-controlled trial to test the original hypothesis that oral prophylaxis with vitamin C attenuates rest and exercise-induced free radical-mediated lipid peroxidation in type 1 diabetes mellitus. All data were collected from hospitalised diabetic patients. The electron paramagnetic resonance spectroscopic detection of spin-trapped alpha-phenyl-tert-butylnitrone (PBN) adducts was combined with the use of supporting markers of lipid peroxidation and non-enzymatic antioxidants to assess exercise-induced oxidative stress in male patients with type 1 diabetes (HbA(1c) 7.9 +/- 1%, n = 12) and healthy controls (HbA(1c) 4.6 +/- 0.5%, n = 14). Following participant randomisation using numbers in a sealed envelope, venous blood samples were obtained at rest, after a maximal exercise challenge and before and 2 h after oral ingestion of 1 g ascorbate or placebo. Participants and lead investigators were blinded to the administration of either placebo or ascorbate treatments. Primary outcome was the difference in changes in free radicals following ascorbate ingestion. Six diabetic patients and seven healthy control participants were randomised to each of the placebo and ascorbate groups. Diabetic patients (n = 12) exhibited an elevated concentration of PBN adducts (p < 0.05 vs healthy, n = 14), which were confirmed as secondary, lipid-derived oxygen-centred alkoxyl (RO.) radicals (a(nitrogen) = 1.37 mT and abeta(hydrogen) = 0.18 mT). Lipid hydroperoxides were also selectively elevated and associated with a depression of retinol and lycopene (p < 0.05 vs healthy). Vitamin C supplementation increased plasma vitamin C concentration to a similar degree in both groups (p < 0.05 vs pre-supplementation) and attenuated the exercise-induced oxidative stress response (p < 0.05 vs healthy). There were no selective treatment differences between groups in the primary outcome variable. These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood. ISRCTN96164937.

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.

Influence of pharmacological experiments of chemicals and other factors in diets of laboratory animals.

PubMed

Newberne, P M

1975-02-01

Results derived from animal experimentation depend to a considerable degree on the health and welfare of the animal from which the results are obtained. This, in turn, reflects the quality of housing, care, and nutrition provided the animal. Most diets designed for a particular species provide a reasonable balance of nutrients in quantities sufficient for normal growth and maintenance and reproduction of that species. Under usual conditions of animal feed manufacture, however, concentrations of essential ingredients may vary appreciably in different batches of a formulation made with different lots of natural ingredients, even though the guaranteed analysis shown on the label remains correct. A feed may also contain intentional or unintentional additives and other biologically active components. Variations in the concentrations of essential dietary components, as well as the presence of extraneous materials, can significantly influence the performance of an experimental animal consuming the diet and can thus lead to a biased interpretation of esperimental results. Investigators must consider factors which can result in efficient or inefficient utilization of energy, the variation in prepared diets whether from natural or purified products, and how these can modify the animal and change the response to a given experimental regimen. Proteins, fat, carbohydrates, vitamins, and minerals can all have pharmacological as well as physiological effects on a biological system. The control of vitamin D metabolism and calcium, parathormone, calcitonin among others are important factors subject to dietary modification. A conditioned marginal or frank deficiency of folic acid can result from oral contraceptives and administration of anticonvulsants; if studies are done in animals using these types of chemicals, dietary folate will be highly significant. Newer information about the role of ascorbic acid in activation of lipase and lipid mobilization is of direct concern to those using research animals requiring a source of dietary ascorbic acid. Trace elements, some amino acids, natural enzyme inducers, and toxic contaminants, all of which can affect the response of experimental animals, are highly important to the quality of animal research in pharmacologic investigations.

Effect of vitamin C on male fertility in rats subjected to forced swimming stress.

PubMed

Vijayprasad, Sanghishetti; Bb, Ghongane; Bb, Nayak

2014-07-01

Stress is defined as a general body response to initially threatening external or internal demands, involving the mobilization of physiological and psychological resources to deal with them. Recently, oxidative stress has become the focus of interest as a potential cause of male infertility. Normally, equilibrium exists between reactive oxygen species (ROS) production and antioxidant scavenging activities in the male reproductive organs. The ascorbic acid is a known antioxidant present in the testis with the precise role of protecting the latter from the oxidative damage. It also contributes to the support of spermatogensis at least in part through its capacity to maintain antioxidant in an active state. Group1: Normal Control animal received Distilled water, Group 2: Positive control (Only Stress), Group 3: Normal rats received an intermediate dose of Vitamin C (20mg/kg/day), Group 4: Stress + Low dose Vitamin C (10mg/kg/day), Group 5: Stress+ Intermediate dose Vitamin C (20mg/kg/day), Group 6: High dose Vitamin C (30mg/kg/day). On 16(th) day effect of stress on body weight, Reproductive organ weight, sperm parameters, and hormonal assay was studied. In the present context, in stress group the sperm count, motility, testicular weight declined significantly. The intermediate dose and high dose of vitamin C showed significantly increased effect on the sperm count and motility. Various physiological changes produced force swimming indicates that swimming is an effective model for producing stress in albino rats. The results suggest that Vitamin C supplementation improves the stress induced reproductive infertility due to both their testosterone increase effect and their antioxidant effect.

Study of the vitamins A, E and C esters penetration into the skin by confocal Raman spectroscopy in vivo

NASA Astrophysics Data System (ADS)

Mogilevych, Borys; Isensee, Debora; Rangel, Joao L.; Dal Pizzol, Carine; Martinello, Valeska C. A.; Dieamant, Gustavo C.; Martin, Airton A.

2015-06-01

Vitamins A, E and C play important role in skin homeostasis and protection. Hence, they are extensively used in many cosmetic and cosmeceutic products. However, their molecules are unstable, and do not easily penetrate into the skin, which drastically decreases its efficiency in topical formulations. Liposoluble derivative of the vitamin A - retinyl palmitate, vitamin E - tocopheryl acetate, and vitamin C - tetraisopalmitoyl ascorbic acid, are more stable, and are frequently used as an active ingredient in cosmetic products. Moreover, increased hydrophobicity of these molecules could lead to a higher skin penetration. The aim of this work is to track and compare the absorption of the liposoluble derivatives of the vitamins and their encapsulated form, into the healthy human skin in vivo. We used Confocal Raman Spectroscopy (CRS) that is proven to be helpful in label-free non-destructive investigation of the biochemical composition and molecular conformational analysis of the biological samples. The measurements were performed in the volar forearm of the 10 healthy volunteers. Skin was treated with both products, and Raman spectra were obtained after 15 min, 3 hours, and 6 hours after applying the formulation. 3510 Skin Composition Analyzer (River Diagnostics, The Netherlands) with 785 nm laser excitation was used to acquire information in the fingerprint region. Significant difference in permeation of the products was observed. Whereas only free form of retinyl palmitate penetrate the skin within first 15 minutes, all three vitamin derivatives were present under the skin surface in case of nanoparticulated form.

The prophylactic effect of vitamin C on induced oxidative stress in rat testis following exposure to 900 MHz radio frequency wave generated by a BTS antenna model.

PubMed

Jelodar, Gholamali; Nazifi, Saeed; Akbari, Abolfazl

2013-09-01

Radio frequency wave (RFW) generated by base transceiver station (BTS) has been reported to make deleterious effects on reproduction, possibly through oxidative stress. This study was conducted to evaluate the effect of RFW generated by BTS on oxidative stress in testis and the prophylactic effect of vitamin C by measuring the antioxidant enzymes activity, including glutathione peroxidase, superoxide dismutase (SOD) and catalase, and malondialdehyde (MDA). Thirty-two adult male Sprague-Dawley rats were randomly divided into four experimental groups and treated daily for 45 days as follows: sham, sham+vitamin C (l-ascorbic acid 200 mg/kg of body weight/day by gavage), RFW (exposed to 900 MHz RFW) 'sham' and 'RFW' animals were given the vehicle, i.e., distilled water and the RFW+vitamin C group (received vitamin C in addition to exposure to RFW). At the end of the experiment, all the rats were sacrificed and their testes were removed and used for measurement of antioxidant enzymes and MDA activity. The results indicate that exposure to RFW in the test group decreased antioxidant enzymes activity and increased MDA compared with the control groups (p < 0.05). In the treated group, vitamin C improved antioxidant enzymes activity and reduced MDA compared with the test group (p < 0.05). It can be concluded that RFW causes oxidative stress in testis and vitamin C improves the antioxidant enzymes activity and decreases MDA.

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.

Assessment of antioxidant activity by using different in vitro methods.

PubMed

Schlesier, K; Harwat, M; Böhm, V; Bitsch, R

2002-02-01

In this study, six common tests for measuring antioxidant activity were evaluated by comparing four antioxidants and applying them to beverages (tea and juices): Trolox equivalent antioxidant capacity assay (TEAC I-III assay), Total radical-trapping antioxidant parameter assay (TRAP assay), 2,2-diphenyl-l-picrylhydrazyl assay (DPPH assay), N,N-dimethyl-p-phenylendiamine assay (DMPD assay), Photochemiluminescence assay (PCL assay) and Ferric reducing ability of plasma assay (FRAP assay). The antioxidants included gallic acid representing the group of polyphenols, uric acid as the main antioxidant in human plasma, ascorbic acid as a vitamin widely spread in fruits and Trolox as water soluble vitamin E analogue. The six methods presented can be divided into two groups depending on the oxidising reagent. Five methods use organic radical producers (TEAC I-III, TRAP, DPPH, DMPD, PCL) and one method works with metal ions for oxidation (FRAP). Another difference between these tests is the reaction procedure. Three assays use the delay in oxidation and determine the lag phase as parameter for the antioxidant activity (TEAC I, TRAP, PCL). They determine the delay of radical generation as well as the ability to scavenge the radical. In contrast, the assays TEAC II and III, DPPH, DMPD and FRAP analyse the ability to reduce the radical cation (TEAC II and III, DPPH, DMPD) or the ferric ion (FRAP). The three tests acting by radical reduction use preformed radicals and determine the decrease in absorbance while the FRAP assay measures the formed ferrous ions by increased absorbance. Gallic acid was the strongest antioxidant in all tests with exception of the DMPD assay. In contrast, uric acid and ascorbic acid showed low activity in some assays. Most of the assays determine the antioxidant activity in the micromolar range needing minutes to hours. Only one assay (PCL) is able to analyse the antioxidant activity in the nanomolar range. Black currant juice showed highest antioxidant activity in all tests compared to tea, apple juice and tomato juice. Despite these differences, results of these in vitro assays give an idea of the protective efficacy of secondary plant products. It is strongly recommended to use at least two methods due to the differences between the test systems investigated.

Stability improvement of natural food colors: Impact of amino acid and peptide addition on anthocyanin stability in model beverages.

PubMed

Chung, Cheryl; Rojanasasithara, Thananunt; Mutilangi, William; McClements, David Julian

2017-03-01

Anthocyanins are prone to chemical degradation and color fading in the presence of vitamin C. The potential of three amino acids (l-phenylalanine, l-tyrosine, l-tryptophan) and a polypeptide (ε-poly-l-lysine) in prolonging the color stability of purple carrot anthocyanins (0.025%) in model beverages (0.05% l-ascorbic acid, citric acid, pH 3.0) stored at elevated temperature (40°C/7 days) was examined. In the absence of amino acids or peptides, anthocyanin degraded at first-order reaction rate. Addition of amino acids or peptide (0.1%) increased the color stability of anthocyanins, with the most significant improvement observed for l-tryptophan. The average half-life of anthocyanin color increased from 2 days to 6 days with l-tryptophan addition. Fluorescence quenching measurements revealed that the l-tryptophan interacted with anthocyanins mainly through hydrogen bonding, although some hydrophobic interaction may also have been involved. Overall, this study suggests that amino acid or peptide addition may prolong the color stability of anthocyanin in beverage products. Copyright © 2016 Elsevier Ltd. All rights reserved.

The SLC23 family of ascorbate transporters: ensuring that you get and keep your daily dose of vitamin C

PubMed Central

May, James M

2011-01-01

The ascorbate transporters SVCT1 and SVCT2 are crucial for maintaining intracellular ascorbate concentrations in most cell types. Although the two transporter isoforms are highly homologous, they have different physiologic functions. The SVCT1 is located primarily in epithelial cells and has its greatest effect in reabsorbing ascorbate in the renal tubules. The SVCT2 is located in most non-epithelial tissues, with the highest expression in brain and neuroendocrine tissues. These transporters are hydrophobic membrane proteins that have a high affinity and are highly selective for ascorbate. Their ability to concentrate ascorbate inside cells is driven by the sodium gradient across the plasma membrane as generated by Na+/K+ ATPase. They can concentrate ascorbate 20 to 60-fold over plasma ascorbate concentrations. Ascorbate transport on these proteins is regulated at the transcriptional, translational and post-translational levels. Available studies show that transporter function is acutely regulated by protein kinases A and C, whereas transporter expression is increased by low intracellular ascorbate and associated oxidative stress. The knockout of the SVCT2 in mice is lethal on day 1 of life, and almost half of SVCT1 knockout mice do not survive to weaning. These findings confirm the importance both of cellular ascorbate and of the two transport proteins as key to maintaining intracellular ascorbate. PMID:21418192

Further Studies on Oxalic Acid Biosynthesis in Oxalate-accumulating Plants 1

PubMed Central

Nuss, Richard F.; Loewus, Frank A.

1978-01-01

l-Ascorbic acid functions as a precursor of oxalic acid in several oxalate-accumulating plants. The present study extends this observation to include Rumex crispus L. (curly dock), Amaranthus retroflexus L. (red root pigweed), Chenopodium album L. (lamb's-quarters), Beta vulgaris L. (sugar beet), Halogeton glomeratus M. Bieb. (halogeton), and Rheum rhabarbarum L. (rhubarb). Several species with low oxalate content are also examined. When l-[1-14C]ascorbic acid is supplied to young seedlings of R. crispus or H. glomeratus, a major portion of the 14C is released over a 24-hour period as 14CO2 and only a small portion is recovered as [14C]oxalate, unlike cuttings from 2- or 4-month-old plants which retain a large part of the 14C as [14C]oxalic acid and release very little 14CO2. Support for an intermediate role of oxalate in the release of 14CO2 from l-[1-14C]ascorbic acid is seen in the rapid release of 14CO2 by R. crispus and H. glomeratus seedlings labeled with [14C]oxalic acid. The common origin of oxalic acid carbon in the C1 and C2 fragment from l-ascorbic acid is demonstrated by comparison of 14C content of oxalic acid in several oxalate-accumulators after cuttings or seedlings are supplied equal amounts of l-[1-14C]- or l-[UL-14C]ascorbic acid. Theoretically, l-[1-14C]ascorbic acid will produce labeled oxalic acid containing three times as much 14C as l-[UL-14C]ascorbic acid when equal amounts of label are provided. Experimentally, a ratio of 2.7 ± 0.5 is obtained in duplicate experiments with six different species. PMID:16660342