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Liu Yanyan - - 2008
The photodynamic properties of a new hypocrellin B (HB) derivative bearing a bispyrrolecarboxamide pendant (HB-Net) were investigated in detail. EPR experiments revealed that the generation ability of reactive oxygen species (ROS) of HB-Net is inferior to that of HB. DNA melting temperature measurements and ethidium bromide (EB) displacement assay illustrated ...
Selmair Patrick L - - 2008
To gain insight into structure-activity relationships of glycolipids in breadmaking monogalactosyl dilinoleylglycerol ( 8) and monogalactosyl monolinoleylglycerol ( 6) were synthesized. Then their functional properties in dough and breadmaking were compared to those of commercial surfactants such as lecithins (from soybean, rapeseed, and sunflower), diacetyltartaric acid esters of monoglycerides (DATEM), ...
Tiwari Brijesh K - - 2008
Freshly squeezed orange juice samples were ozonated with control variables of gas flow rate (0-0.25 L min (-1)), ozone concentration (0.6-10.0%w/w), and treatment time (0-10 min). Effects of ozone processing variables on orange juice quality parameters of pH, degrees Brix, titratable acidity (TA), cloud value, nonenzymatic browning (NEB), color values ...
Riess Kevin P - - 2009
BACKGROUND: To determine the prevalence of ascorbic acid deficiency in the surgical population, whether the body mass index (BMI) has an effect on ascorbic acid concentrations; and whether an association exists between ascorbic acid deficiency and adverse surgical outcomes. METHODS: Preoperative plasma ascorbic acid concentrations were prospectively assessed in 20-60-year-old ...
Santos Ricardo M - - 2008
The measurement of Nitric oxide (NO) in real-time has been a major concern due to the involvement of this ubiquitous free radical modulator in several physiological and pathological pathways in tissues. Here we performed a study aiming at evaluating different types of carbon fibers, namely Textron, Amoco, Courtaulds and carbon ...
Wei Xiaoling - - 2008
In sodium acetate-acetic acid buffer solution, Au, Ag, Pt, Pd, Fe3O4, and Cu2O nanoparticles have catalytic enhancement effect on the reduction of Cu2+ by ascorbic acid to form large copper particles that exhibit a strong resonance scattering peak at 610 nm. Those nanocatalytic reactions were studied by the resonance scattering ...
Newsom Sean A - - 2008
The thermic effect of feeding (TEF: increase in energy expenditure following acute energy intake) is an important physiological determinant of total daily energy expenditure and thus energy balance. Approximately 40% of TEF is believed to be mediated by sympathoadrenal activation and consequent beta-adrenergic receptor stimulation of metabolism. In sedentary adults, ...
Hoffer L J - - 2008
BACKGROUND: Ascorbic acid is a widely used and controversial alternative cancer treatment. In millimolar concentrations, it is selectively cytotoxic to many cancer cell lines and has in vivo anticancer activity when administered alone or together with other agents. We carried out a dose-finding phase I and pharmacokinetic study of i.v. ...
Takebayashi Jun - - 2008
The antioxidant activity of a provitamin C agent, 2-O-beta-D-glucopyranosyl-L-ascorbic acid (AA-2betaG), was compared to that of 2-O-alpha-D-glucopyranosyl-L-ascorbic acid (AA-2G) and ascorbic acid (AA) using four in vitro methods, 1,1-diphenyl-picrylhydrazyl (DPPH) radical-scavenging assay, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS(*+))-scavenging assay, oxygen radical absorbance capacity (ORAC) assay, and 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced erythrocyte hemolysis ...
Abbaspour Abdolkarim - - 2008
A method for the determination of ascorbic acid in vitamin C tablets based on a very simple paptode design on TLC strips is described. This procedure is based on the reduction of iron(III) with ascorbic acid and the formation of a colorful red complex with immobilized 2,2'-dipyridyl (dipy) on TLC ...
Seto Aaron - - 2008
Ionizing radiation could supplement tissue bank screening to further reduce the probability of diseases transmitted by allografts if denaturation effects can be minimized. It is important, however, such sterilization procedures be nondetrimental to tissues. We compared crosslinking and free radical scavenging potential methods to accomplish this task in tendon tissue. ...
Castro Maite A - - 2008
In this paper, we present a novel function for ascorbic acid. Ascorbic acid is an important water-soluble antioxidant and cofactor in various enzyme systems. We have previously demonstrated that an increase in neuronal intracellular ascorbic acid is able to inhibit glucose transport in cortical and hippocampal neurons. Because of the ...
Prasad Bhim Bali - - 2008
Clinical manifestations owing to ascorbic acid deficiency demand an easy-to-use, rapid, robust and inexpensive technique, which can measure serum ascorbic acid at ultratrace level to attend the problem of hypovitaminosis C and acute cases of scurvy. In the present work, a novel molecularly imprinted polymer (MIP)-coated solid-phase microextraction (SPME) fiber ...
Kumar S Ashok - - 2008
A simple selective method for determination of ascorbic acid using polymerized direct blue 71 (DB71) is described. Anodic polymerization of the azo dye DB71 on glassy carbon (GC) electrode in 0.1M H(2)SO(4) acidic medium was found to yield thin and stable polymeric films. The poly(DB71) films were electroactive in wide ...
Enami Shinichi - - 2008
The pulmonary epithelium, like most aerial biosurfaces, is naturally protected against atmospheric ozone (O(3)) by fluid films that contain ascorbic acid (AH(2)) and related scavengers. This mechanism of protection will fail, however, if specific copollutants redirect AH(2) and O(3)(g) to produce species that can transduce oxidative damage to underlying tissues. ...
Abbasi A - - 2008
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 ...
Hancock Robert D - - 2008
Analysis of phloem exudates from the fruit of Cucurbitaceae revealed the presence of several compounds with UV-visible absorption spectra identical to that of l-ascorbic acid. In Cucurbita pepo L. (zucchini), the compounds could be isolated from phloem exudates collected from aerial parts of the plant but were not detected in ...
Harrison Fiona E - - 2008
Oxidative stress is implicated in the cognitive deterioration associated with normal aging as well as neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. We investigated the effect of ascorbic acid (vitamin C) on oxidative stress, cognition, and motor abilities in mice null for gulono-gamma-lactone oxidase (Gulo). Gulo-/- mice are unable ...
Lester Gene E - - 2008
Orange-fleshed, non-netted honeydew ( Cucumis melo L.) is a relatively new melon in the marketplace and has shown a lot of potential as an alternative to netted muskmelons (cantaloupes), which are often prone to surface contamination by enteric bacteria. Orange-fleshed honeydew is a cross between orange-fleshed cantaloupe and non-netted, green-fleshed ...
Nováková Lucie - - 2008
Hydrophilic interaction liquid chromatography (HILIC) method using internal standard for the determination and stability study of ascorbic acid was developed. HILIC method was very fast and simple using the following analytical conditions: ZIC HILIC (150 x 2.1 mm, 3.5 microm) chromatographic column and mobile phase composed of ACN and 50 ...
Prajapati Santosh Kumar - - 2008
To assess the dust interception efficiency of some selected tree species and impact of dust deposition on chlorophyll and ascorbic acid content of leaves the present study was undertaken. The plant species selected for the study were Ficus religiosa, Ficus benghalensis, Mangifera indica, Dalbergia sissoo, Psidium guajava, and Dendrocalamus strictus. ...
Hou Shurong - - 2008
A polymerized film of 3,5-dihydroxy benzoic acid (DBA) was prepared on the surface of a glassy carbon electrode (GCE) in neutral solution by cyclic voltammetry (CV). The poly(DBA) film-coated GCE exhibited excellent electrocatalytic activity toward the oxidation of dopamine (DA). A linear range of 1.0 x 10(-7) to 1.0 x ...
Heinrich Ulf-Rüdiger - - 2008
OBJECTIVES: Noise-induced hearing loss can be caused, among other causes, by increased nitric oxide (NO) production in the inner ear leading to nitroactive stress and cell destruction. Some studies in the literature suggest that the degree of hearing loss (HL) could be reduced in an animal model through ascorbic acid ...
Shadyro Oleg - - 2008
Effects of ascorbic acid (AA), ascorbic acid glycoside (AAG) and alpha-tocopherol monoglycoside (TMG) on radiation - and H(2)O(2)-induced decomposition of thymine in aqueous solutions were investigated. Of the three compounds studied, AAG was found to possess the most marked protector properties. An explanation of this phenomenon has been given in ...
Stevens R - - 2008
Quantitative trait loci (QTL) mapping is a step towards the identification of factors regulating traits such as fruit ascorbic acid content. A previously identified QTL controlling variations in tomato fruit ascorbic acid has been fine mapped and reveals that the QTL has a polygenic and epistatic architecture. A monodehydroascorbate reductase ...
Pietraforte D - - 2008
Clenbuterol (CLB) is an antiasthmatic drug used also illegally as a lean muscle mass enhancer in both humans and animals. CLB and amine-related drugs in general are nitrosatable, thus raising concerns regarding possible genotoxic/carcinogenic activity. Oral administration of CLB raises the issue of its possible transformation by salivary nitrite at ...
Samappito S - - 2008
This experiment was carried out in the rainy season (May-October) of the 2006 at the Department of Biotechnology, Faculty of Technology, Mahasarakham University, Mahasarakham 44000, Thailand to analyse organic acids contents in ripe fruits of fifteen Mao Luang cultivars harvested from dipterocarp forest, Phupan Valley, Sakon Nakhon, Northeast Thailand. The ...
Ogawa Eri - - 2008
Uptake and recycling of ascorbic acid (AA) were studied in erythrocytes of 1- to 12-month-old Beagle dogs. At 1 month, both AA uptake and recycling capacity were high. Ascorbic acid entered erythrocytes mainly in the oxidized form with elevated activity of Glut 1 glucose transporter. However, this trait of erythrocytes ...
Shibayama Hiroharu - - 2008
The novel amphiphilic vitamin C derivative disodium isostearyl 2-O-L-ascorbyl phosphate (VCP-IS-2Na), which has a C(18) alkyl chain attached to the stable ascorbate derivative sodium L-ascorbic acid 2-phosphate (VCP-Na), was evaluated for reduction of cell damage induced by oxidative stress, ultraviolet A (UVA), ultraviolet B (UVB), and H(2)O(2); stimulation of collagen ...
Olatunji-Bello I I - - 2008
BACKGROUND: Smoke from the average cigarette contains chemicals, which are highly toxic, causing chronic airways diseases in smokers as well as non-smokers exposed to environmental tobacco smoke (ETS). It is associated with an increased risk of developing asthma, pneumonia, bronchitis and cancer. OBJECTIVE: To investigate the effect of ascorbic acid ...
Murata Masatsune - - 2008
Furfural is an important intermediate compound of the Maillard reaction of pentose or ascorbic acid. We examined the browning of furfural and lysine by heating these compounds in solution and found two yellow compounds. The first, furpipate, is a novel pipecolic acid derivative and was (Z)-3-(2-furylmethylidene)-3H, 4H, 5H, 6H-pyridine-2-carboxylic acid. ...
Turick Charles E - - 2008
Melanin production by Shewanella algae BrY occurred during late- and (or) post-exponential growth in lactate basal salts liquid medium supplemented with tyrosine or phenylalanine. The antioxidant ascorbate inhibited melanin production but not production of the melanin precursor homogentisic acid. In the absence of ascorbate, melanin production was inhibited by the ...
Preechaworapun Anchana - - 2008
In this paper, we have critically evaluated the electrochemical behavior of the products of seven substrates of the enzyme label, alkaline phosphate, commonly used in electrochemical immunosensors. These products (and the corresponding substrates) include indigo carmine (3-indoyl phosphate), hydroquinone (hydroquinone diphosphate), 4-nitrophenol (4-nitrophenol phosphate), 4-aminophenol (p-aminophenyl phosphate), 1-naphthol (1-naphthyl phosphate), ...
Mosca Monica - - 2008
A biocompatible water-in-oil (W/O) emulsion has been used as a model to study the effect of ascorbic acid (AA) on the oxidation of the oil (glycerol trioleate, GTO) continuous phase. The model system consisted of 3 wt % water dispersed in GTO containing 0.5 wt % sodium oleate (NaO)/oleic acid ...
Paoletti Elena - - 2008
Treatments with ethylenediurea (EDU) protect plants from ozone foliar injury, but the processes underlying this protection are poorly understood. Adult ash trees (Fraxinus excelsior), with or without foliar ozone symptoms in previous years, were treated with EDU at 450 ppm by gravitational trunk infusion in May-September 2005 (32.5 ppm h ...
Shahidi Siamak - - 2008
Ascorbic acid (vitamin C) is required for health and, in particular, its supplementation has beneficial effects in some pathological conditions. There are conflicting reports regarding the usefulness of ascorbic acid in the treatment of dementia. In this study, we investigated the effects of acute, short- and long-term pre-training administration of ...
Lode Holger N - - 2008
BACKGROUND: The replacement of established evidence-based cancer therapy protocols (mainstream therapy) by unevaluated complementary and alternative medicine (CAM) is a challenge in pediatric oncology. We tested the hypothesis that oral application of L-lysine and ascorbic acid (Lysin C Drink) in combination with epigallocatechin-gallate (EGCG) and amino-acids (Epican forte) is effective ...
Gautier Hélène - - 2008
The objective of this study was to understand the respective impact of ripening stage, temperature, and irradiance on seasonal variations of tomato fruit quality. During ripening, concentrations in reducing sugars, carotenes, ascorbate, rutin, and caffeic acid derivates increased, whereas those in titratable acidity, chlorophylls, and chlorogenic acid content decreased. Fruit ...
Ghosh S - - 2008
The root nodules of Phaseolus mungo (L.), a herbaceous leguminous pulse, contain high amounts of ascorbic acid (AsA). A glucose pool present in the nodule might serve as precursor for AsA production. From root nodule, a Rhizobium sp. was isolated. The symbiont produced a large amount of AsA (290.5 microg/ml) ...
Crans Debbie C - - 2008
The anti-oxidant properties of L-ascorbic acid were investigated in the confined medium produced by a sodium bis(2-ethylhexyl)sulfosuccinate (aerosol-OT, AOT) self-assembled reverse micelle. Using 1H-1H NOESY (proton-proton 2D nuclear overhauser enhancement correlation spectroscopy) NMR spectroscopy, the location of ascorbic acid was investigated and found to be at the AOT-interface in contrast ...
Wolfrum Bernhard - - 2008
We have developed a chip-based nanofluidic device to amplify the electrochemical signal of catechols by orders of magnitude. The amplification is based on rapid redox cycling between plane parallel electrodes inside a nanochannel. We show that it is possible to monitor the signal of only a few hundred molecules residing ...
Pisoschi Aurelia Magdalena - - 2008
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 ...
de la Torre Daniel - - 2008
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 ...
Paulikova H - - 2008
Cytotoxic/cytostatic activity of N-salicylidene-L-glutamato diaqua copper(II) complex (CuC) against mice leukemia cells L1210 has been estimated and their bioactivity was enhanced by addition of ascorbic acid. The Cu-complex with isoquinoline ligand (IQ-CuC) had stronger cytostatic effect (IC50 =15.6 microM) than parental complex (CuC) and its cytotoxicity several times increased in ...
Koc Murat - - 2008
Reactive oxygen species (ROS) have been implicated in the etiology of indomethacin-induced gastric mucosal damage. This study investigated ascorbic acid (vitamin C)'s protective effects against oxidative gastric mucosal damage induced by indomethacin. Ascorbic acid is a powerful antioxidant because it can donate a hydrogen atom and form a relatively stable ...
Tikare Swati N - - 2008
Nickel-induced hyperglycemia in rats under both acute and subchronic exposure conditions could be due to increased hepatic glycogenolysis, increased pancreatic release of glucagon, decreased peripheral utilization of glucose, or gluconeogenesis. We studied the effect of acute and subchronic nickel sulfate treatment on Wister strain male albino rats simultaneously treated with ...
Retana-Ugalde Raquel - - 2008
AIM: To determine the useful dosage of ascorbic acid and alpha-tocopherol against oxidative stress and DNA damage in the elderly. METHODS: A double-blind controlled clinical assay carried out in a sample of 66 healthy subjects divided into three age-paired random groups with 22 subjects in each group. Group A received ...
Rossi Silvia - - 2008
The aim of the present work was to investigate if chitosan salification with ascorbic acid could produce an increase in chitosan penetration enhancement properties towards buccal mucosa and intestinal Caco-2 cell monolayer. Three different chitosan grades were considered. Chitosan hydrochloride and lactate were used as references. Fluorescein isothiocyanate-dextran (FD4), a ...
Leclerc Patrice C - - 2008
BACKGROUND: Ascorbic acid is an essential vitamin and a powerful antioxidant. Many studies have highlighted the benefits of ascorbic acid for chronic cardiovascular diseases such as hypertension in which angiotensin II (Ang II) plays an significant role. We therefore hypothesized that ascorbic acid could modify the pharmacological properties of the ...
Yillar D O - - 2008
The stability of choline ascorbate was studied considering concentration, temperature, and pH of the drug solution. Our results revealed that choline ascorbate is almost fully stable with respect to these parameters. Practically no loss was observed when 3 x l0(-1) (50%) drug solution is preserved in the refrigerator, at ambient ...
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