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In recent years, the exploration of the therapeutic potential of Salvia has gained considerable attention, leading to a growing number of scientific studies emphasizing its pharmacological properties. Despite this, therapeutic applications of Salvia remain underexploited, requiring further investigation. Iran is a major center for sage diversity in Asia, boasting 60 Salvia species, 17 of which are unique to the area. This study aimed to comprehensively explore and compare the extracts of 102 Salvia samples belonging to 20 distinct Salvia species from Iran, providing a deeper understanding of their specific polyphenol content and, consequently, their antioxidant capabilities and potential therapeutic uses. All samples were analyzed to determine the contents of total phenolics, total flavonoids, total tannin, photosynthetic pigments, and ascorbic acid, along with their antioxidant activity. These data were then combined with the forty distinct chemical fingerprints identified by ultrafast high-pressure liquid chromatography coupled with high-resolution mass spectrometry. Multivariate data analysis was employed to find correlations and differences among the huge number of data obtained and to identify Salvia species with similar phytochemical and/or antioxidant properties. The results show that each Salvia species is characterized by a distinct class of polyphenols recognized for their antidiabetic, anti-inflammatory, cardioprotective and neuroprotective properties. Overall, our findings reveal the potential of some Salvia species for targeted therapeutic applications and provide a rational basis for the development of Salvia-derived nutraceuticals, ultimately improving the prospects for the use of Salvia in medicine. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the potential therapeutic effects of Piper chaba (PC) growing in the northern region of India, having differences in the phytochemicals, nutritional content, antimicrobial and antioxidant properties by reducing power assay (RPA), 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, phosphomolybdate assay, and antidiabetic potential by α-amylase assay with change in the geographical location. Outcomes of the gas chromatography–mass spectrometry (GC–MS) analysis revealed that phytochemicals such as piperine (46.69%), kusunokinin (8.9%), and sitostenone (7.57%) are the prominent compounds found in PC. The plant has also shown a good nutritional value, i.e., iron (11.25 mg), calcium (147 mg), and vitamin C (9.30 mg) per 100 g. PC has a higher phenolic content than other species (⁓ 13.75 g/100 g plant powder). Among the four tested bacterial strains, the extract is best responsive toward Escherichia coli (35 ± 0.68 mm) which is more than the standard ciprofloxacin (24 ± 0.8 mm). Similarly, among two tested fungal strains, Saccharomyces cerevisiae shows the best zone of inhibition (ZOI) (27.5 ± 0.8 mm), which is greater than tat of standard amphotericin (20.25 ± 0.28 mm). The DDPH method demonstrated the highest antioxidant activity (⁓ 42.61 ± 1.82 µg/ml). IC50 for the antidiabetic potential of PC was found to be 23.09 ± 0.3 µg/ml against α-amylase assay. A molecular docking study revealed that three compounds, piperine, sitostenone and kusunokinin, showed strong binding affinity toward bacterial tyrosyl-tRNA synthetases, fungal dihydrofolate reductase, and α-amylase, respectively. Therefore, the findings of the current study indicate that PC can be considered as a source of food and medicines, either in the form of traditional preparations or as pure active constituents. [ABSTRACT FROM AUTHOR]

Phototoxicity is an important issue in fluorescence live imaging of light-sensitive cellular processes such as mitosis. Among several approaches to reduce phototoxicity, the addition of antioxidants to the media has been used as a simple method. Here, we analyzed the impact of phototoxicity on the mitotic progression in fluorescence live imaging of human cells and performed a screen to identify the most efficient antioxidative agents that reduce it. Quantitative analysis shows that high amounts of light illumination cause various mitotic defects such as prolonged mitosis and delays of chromosome alignment and centrosome separation. Among several antioxidants, our screen reveals that ascorbic acid significantly alleviates these phototoxic effects in mitosis. Furthermore, we demonstrate that adding ascorbic acid to the media enables fluorescence imaging of mitotic events at very high temporal resolution without obvious photodamage. Thus, this study provides an optimal method to effectively reduce the phototoxic effects in fluorescence live cell imaging. Ascorbic acid alleviates phototoxic effects of fluorescence live imaging in mitosis, allowing for very high temporal resolution without photodamage. [ABSTRACT FROM AUTHOR]

Background: Faba bean attacked by soil-borne pathogens causing root rot disease. This disease has serious damage to both plant stand and produced yield. The present study aimed to evaluate effectiveness of the bioagents; Trichoderma harzianum and some plant resistance inducers as fungicide alternatives against root rot disease incidence at both pre- and post-emergence growth stages. Results: Under open greenhouse conditions, the incidence of faba bean root rot in pre- and post-emergence growth phases was considerably reduced by using six inorganic salts and five antioxidants individually or combining with each other or with the bio-stimulator T. harzianum that exceeded the used fungicide, Rhizolex-T. Application of enervit agitated the highest significant defensive impact during pre-emergence stage versus root rot incidence (5.0%), followed by calcium sulfate and [cysteine + T. harzianum] (6.7%). At post-emergence stage, majority of the treatments completely suppressed (100.0%) root rot incidence, except vitamax plus and the fungicide (Rizolex-T) which expressed by 91.7 and 18.8%, respectively. Duplicate irrigations of 23 treatments after faba bean dressing improved the synthesis of different protein contents with the 2nd of which enhanced higher protein contents than the 1st one, except [T. harzianum + vitamin E + vitamin C + enervit + selenium + vitamax plus], [T. harzianum + vitamax plus] and cysteine. Disodium phosphate induced the highest catalase (CAT) activity (1820.8 and 1677.2 U/g FWt) after both irrigations. [T. harzianum + vitamax plus] and vitamin E induced the highest peroxidase (POD) activity 217.4 and 356.9 U/g FWt after 1st and 2nd irrigations, respectively. Disodium phosphate and [T. harzianum + vitamin E + vitamin C + enervit + selenium + vitamax plus] induced the highest chitinase (CHIA) activity 52.8 and 54.4 U/g FWt after 1st and 2nd irrigations, respectively. Application of disodium phosphate, calcium sulfate, potassium metabisulfite, sodium sulfate, cysteine, [cysteine + potash alum], enervit, vitamin E, [vitamin E + vitamin C + enervit + selenium + vitamax plus], [T. harzianum + enervit], [T. harzianum + selenium], [T. harzianum + vitamin E], [T. harzianum + vitamin E + vitamin C + enervit + selenium + vitamax plus] and vitamin C stimulated the formation of new protein bands on SDS-PAGE after the 2nd irrigation treatment. Conclusions: Such treatments are considered good and environmentally safe alternatives against root diseases for getting rid of the negative effects of fungicides. [ABSTRACT FROM AUTHOR]

The reactivity of coulometric titrants (bromine, iodine, and hexacyanoferrate(III) ions) with respect to the antioxidants (AOs) of beer is evaluated. It is shown that electrogenerated iodine interacts with ascorbic acid and sulfur-containing compounds, but does not oxidize phenolic AOs. The stoichiometric coefficients of reactions of phenolic AOs with electrogenerated bromine and hexacyanoferrate(III) ions are found. A comprehensive assessment of the antioxidant properties of beer is carried out through overall antioxidant parameters (total antioxidant capacity (TAC) according to the reaction with electrogenerated bromine, ferric reducing power (FRP) according to the reaction with electrogenerated hexacyanoferrate(III) ions, and oxidation by). Sixteen samples, differing in the type of fermentation, variety, and style, are considered. A statistically significant difference between the parameters for individual samples is shown. The TAC and FRP of beer correlate with the total concentration of phenolic compounds and antioxidant activity (r = 0.7175–0.8703 at rcrit = 0.4973), which confirms the correctness of the results obtained using coulometric titration. Differences in the overall antioxidant parameters of the top-fermented and bottom-fermented beers, as well as filtered and unfiltered light and dark beers, are statistically insignificant (p = 0.10–0.82). The change in the overall antioxidant parameters of beer during storage in air is evaluated. [ABSTRACT FROM AUTHOR]

Green fabrication is an environmentally friendly and innovative method, and an attractive research field for the production of magnesium oxide nanoparticles (MgO NPs) in clinical and environmental applications. In this study, a viable green synthetic approach has been carried out to produce MgO NPs by using leaf aqueous extract of Piper nigrum as a capping agent. The formation and physicochemical properties of the MgO NPs were confirmed through standard characterization methods. All the analytical data revealed the formation of pure, rod-shaped, and crystalline MgO NPs with an average size of 20 nm. The low concentration of 50 µg/mL MgO NPs shows 29.99% free radical scavenging, whereas the highest concentration of 500 µg/mL MgO NPs exhibits 91.99% free radical scavenging compared with ascorbic acid. The IC50 of the MgO NPs was found to be 89.5 µg/mL. This study shows that the synthesized MgO NPs exhibit good anti-oxidant activity that can be used for biomedical applications. [ABSTRACT FROM AUTHOR]

Natural enzymes have excellent catalytic activity. However, due to their unstable nature and high cost, current research has turned to the synthesis and development of enzyme-like nanomaterials and single-atomic nanozymes. In this study, a single-atomic palladium-loaded nitrogen-doped porous carbon catalyst (SA-Pd/NPC) was prepared and used as a mimetic peroxidase to catalyze the substrates oxidation. The catalytic capability of the SA-Pd/NPC was tested by the TMB-H2O2 system, and it expressed a superior catalytic capability owing to the plentiful catalytic centers of the single-atom Pd, its high porosity, the large specific surface area, and the strong electron transfer capability of the NPC. For the color reaction of TMB, thiol antioxidants (e.g., glutathione, GSH) and non-thiol antioxidants (e.g., ascorbic acid, AA) are suitable for different inhibition mechanisms. GSH and AA are typical substances of these two main antioxidant types, respectively. Here, we demonstrate that this prepared catalyst could be used to simultaneously determine a variety of major known physiologically relevant thiol-containing and thiol-free antioxidants, accompanied by a blue color gradient change with UV–Vis spectra at 652 nm through the SA-Pd/NPC-catalyzed TMB-H2O2 system. Linear responses to GSH and AA could be obtained in the concentration ranges of 0.01–0.10 mM and 1–13 μM (both R2 values were greater than 0.970), respectively, while the limits of detection were 3 μM and 0.3 μM, respectively. The ability of the nanozyme to detect overall antioxidant levels (TAL) was also confirmed in subsequent tests on artificial saliva and biological samples. [ABSTRACT FROM AUTHOR]

The chemistry of metallo-enzymatic antioxidants viz. superoxide dismutase (SOD), catalase (CAT), and peroxidase was presented in the first part. In the second part, the biochemistry of metal-free antioxidant enzymes, viz. thioredoxin, peroxiredoxin, glutathione S-transferases, and glutathione peroxidase were illustrated. The sources, synthesis, antioxidant properties, functions, mechanistic aspects, and applications of natural and generic compounds, viz. vitamin C, vitamin E, β-carotene, and glutathione are presented in the third and last part of this series article. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Strategic design, theoretical insights, synthesis, and unveiling antioxidant potential in a novel ascorbic acid analog" published in the Journal of Molecular Modeling. The correction states that the author list for the article should read Taki Eddine Ahmed Ardjani, Sofiane Daoudi, Mohamed Rafik Benaissa, and Juan Raul Alvarez-Idaboy. The original article has been corrected. The correction notice also includes the institutional affiliations of the authors. Springer Nature, the publisher, remains neutral with regard to jurisdictional claims and institutional affiliations. [Extracted from the article]

Background: Pyrazoles have attracted particular attention due to the diverse biological activities associated with this heterocyclic system, and some have been shown to be cytotoxic to several human cell lines. Several drugs currently on the market have this heterocycle as the key structural motif, and some have been approved for the treatment of different types of cancer. Results: 4,4ʹ-(Arylmethylene)bis(1H-pyrazol-5-ols) derivatives 3a–q were synthetized by a three components reaction of 3-methyl-1-phenyl-5-pyrazolone (1) with various benzaldehydes 2 catalyzed by sodium acetate at room temperature. The structures of all synthesized compounds were characterized by physicochemical properties and spectral means (IR and NMR) and were evaluated for their radical scavenging activity by DPPH assay and tested in vitro on colorectal RKO carcinoma cells in order to determine their cytotoxic properties. All 4,4ʹ-(arylmethylene)bis(1H-pyrazol-5-ols) derivatives 3a–q were synthetized in high to excellent yield, and pure products were isolated by simple filtration. All compounds have good radical scavenging activity, and half of them are more active than ascorbic acid used as standard. Conclusion: Several derivatives proved to be cytotoxic in the RKO cell line. In particular, compound 3i proved to be a very potent scavenger with an IC50 of 6.2 ± 0.6 µM and exhibited an IC50 of 9.9 ± 1.1 μM against RKO cell. Autophagy proteins were activated as a survival mechanism, whereas the predominant pathway of death was p53-mediated apoptosis. [ABSTRACT FROM AUTHOR]

The aim was to evaluate the effect of different antioxidant agents on the improvement of bond strength to enamel subjected to a whitening procedure. Samples were divided into six groups (n = 10): control; whitening immediately followed by restorative treatment (WHT); whitening and restoration after a 7-day period (WHT_7D); whitening and application of 10% sodium ascorbate (WHT_SA); application of 5% grape seed extract (WHT_GS); and application of 5% green tea (WHT_GT). All groups except for control fwere whitened (Opalescence PF Regular 16%) for 7 days (4 h/day). All samples were restored (Optibond™ FL, Kerr and Filtek™ Z250 composite, 3M ESPE). In antioxidant groups these were applied for 15 min and immediately restored. Specimens were sectioned in microspecimens (1.0 ± 0.2 mm2 area) for microtensile bond strength (μTBS) testing (0.5 mm/min) on a universal testing machine. ANOVA test with Brown-Forsythe correction and Games-Howell post-hoc test was used (significance level of 5%). Antioxidant groups presented significant higher mean μTBS values than group WHT (p < 0.001). The non-whitened control group was not significantly different to antioxidant experimental groups. Group WHT_7D exhibited a significantly higher mean μTBS value when compared to group WHT (p = 0.022). The different antioxidants significantly influenced microtensile bond strength of restored teeth after whitening. [ABSTRACT FROM AUTHOR]

Ascorbic acid is among the most abundant antioxidants in the lung, where it likely plays a key role in the mechanism by which particulate air pollution initiates a biological response. Because ascorbic acid is a highly redox active species, it engages in a far more complex web of reactions than a typical organic molecule, reacting with oxidants such as the hydroxyl radical as well as redox-active transition metals such as iron and copper. The literature provides a solid outline for this chemistry, but there are large disagreements about mechanisms, stoichiometries and reaction rates, particularly for the transition metal reactions. Here we synthesize the literature, develop a chemical kinetics model, and use seven sets of laboratory measurements to constrain mechanisms for the iron and copper reactions and derive key rate constants. We find that micromolar concentrations of iron(III) and copper(II) are more important sinks for ascorbic acid (both AH2 and AH−) than reactive oxygen species. The iron and copper reactions are catalytic rather than redox reactions, and have unit stoichiometries: Fe(III)/Cu(II) + AH2/AH− + O2 → Fe(III)/Cu(II) + H2O2 + products. Rate constants are 5.7 × 104 and 4.7 × 104 M−2 s−1 for Fe(III) + AH2/AH− and 7.7 × 104 and 2.8 × 106 M−2 s−1 for Cu(II) + AH2/AH−, respectively. [ABSTRACT FROM AUTHOR]

The antioxidant composition from four samples, brewer's spent grain (BSG), brewer's spent yeast (BRY), a part of the process (POP—after hop addition), and craft beer (CRB) from five popular craft beers were evaluated. The total phenolics, flavonoids, tannins, and ascorbic acid, as well as the antioxidant capacity, were determined. Furthermore, phenolics content was determined by LC–MS/MS technique. The cytotoxicity of BRY on fibroblasts cells and the anti-tumor effect of craft beers on colon adenocarcinoma cells were determined by cell viability and membrane integrity assays. The darker samples presented the highest total phenolics and antioxidant capacities. Phenolics, tannins, and ascorbic acid showed a strong correlation with antioxidant activity. Moreover, among nine phenolics characterized, catechin, and ferulic and p-coumaric acids were the majority compounds. Besides, no cytotoxicity was detected by BRY samples, and the darker craft beers, American Ipa and Imperial Stout demonstrated antiproliferative activity in the tumor cell line. Therefore, the comprehensive vision of the antioxidants into the entire brewing process is useful to optimize and valorize the end product and residues. This study also enlightened the potential benefits to human health, pointing new approaches to increase the interest in craft beer and its bioproducts avoiding the high costs of discard and possible negative impacts on the environment. [ABSTRACT FROM AUTHOR]

The effects of ultraviolet-C light (UVC) on vitamin C and phenolic compounds in acerola during postharvest storage were investigated in order to elucidate the mechanism inducing the antioxidant systems. The fruits, stored at 10 °C for 7 days after a hormetic UVC irradiation (two pulses of 0.3 J/cm2), showed significantly less degradation of vitamin C and phenolic compounds than the control without the UVC challenge. UVC activated the L-galactono-1,4-lactone dehydrogenase (GalDH), a key enzyme for vitamin C biosynthesis, and altered the composition of phenolic compounds, through phenolic biosynthesis, in acerola during postharvest storage. UVC also induced reactive oxygen species (ROS) productions at immediate (day 0) and late (day 7) times during postharvest storage through the mitochondrial electron transport chain and NADPH oxidase, respectively. Results suggest that UVC helps in the retention of vitamin C and phenolic content in acerola by altering ascorbic acid and phenolic metabolism through an increase in mitochondrial activity and a ROS-mediated mechanism. Data showed the beneficial effects of UVC on maintenance of nutraceutical quality in acerola during postharvest storage and supplied new insights into understanding the mechanism by which UVC irradiation enhance the antioxidant system in fruits. [ABSTRACT FROM AUTHOR]

Background: Citrus reticulata is one of the most cultivated fruit with great benefits for humans in the world. Citrus reticulata peel has several biological activities within them hypoglycemic, hepatoprotective, antimicrobial and antioxidant. The present study emphasizes on the in vivo wound healing and in vitro antimicrobial and antioxidant activities of Citrus reticulata peel extract. Methods: Forty albino mice (23–29 g) of either sex were divided into four groups. The test groups were treated with experimental ointment (0.5% and 10% of methanolic extract), negative control were treated with Vaseline and the positive control were treated with silver sulfadiazine. Burn wounds were induced on dorsal area of mice bodies. Wound area measurement was carried out every day during 22 days. Biochemical screening was performed to identify possible compounds. Antioxidant and antimicrobial activities were also determined. Results: Significant wound healing activity was observed with topical application of Citrus reticulata peel extract. Wound area reduction at day 16 of treatment was 100% for both treated groups (0.5% and 10%) when compared to positive and negative control it was 100% and 98.32% respectively at day 22. Furthermore higher rate of wound contraction (100% on 16th day) was observed for both treated groups. The result of biochemical screening showed that C. reticulata peel is characterized by highest amount of total polyphenols (13.19 mg/g), flavonoids (4.07 mg/g), vitamin C (13.20 mg/g), carotenoids (0.032 mg/g) and lowest content of macronutrients (Proteins: 0.40%, reducing sugars: 7.21%; lipids: 1.5%). Additionally C. reticulata peel exhibited remarkable antioxidant activity using DPPH and phosphomolybdate methods as well as the extract possess antimicrobial effect against pathogen bactria. Conclusion: The findings from this research indicated that Citrus reticulata peel extract is effective in inhibiting the growth of pathogen bacteria and could be of therapeutic potentials for wound healing. [ABSTRACT FROM AUTHOR]

Chilli pepper is a widely spread vegetable crop and one of the main spices used all over the world. Its properties comprise high antioxidant capacity and content of several healthy-related compounds including vitamin C, carotenoids and capsaicinoids. In countries of the Mediterranean basin, chilli production is largely based on local varieties traditionally selected for open field conditions, although, the genetic improvement is a rapidly growing sector toward the development of hybrids. In the present study, nine chilli pepper varieties with diverse market destinations including powder consumption, canned production, and blister packaging as well as seven hybrids obtained through half-diallel crosses between the parent varieties were grown in replicated field trials over diverse locations and evaluated in a comprehensive approach regarding twenty-six quantitative agronomic, morphological and health-related phytochemical traits. Significant differences between hybrids and parents were found for 12 out of the 26 traits studied in both environments. Agronomic and chemical traits did not differ significantly except than for total yield and pH. Several biochemical traits differed significantly and carotenoids and ascorbic acid values were mostly linked to the cultivation environment. A significant effect of the genotype (P < 0.01) was found in all traits for both parental lines and hybrids. The phenotypic plasticity revealed high stability for fruit morphological traits in both parents and hybrids. Greater plasticity was found for total yield in the parent lines, while hybrids were more stable for capsaicinoids and more plastic for carotenoids and AsA, compared to parental. Significant mid-parent heterosis was observed in all the hybrids tested for at least one of the trait evaluated. The PCA in the first two dimensions explained 48.26% of the total variance showing a distinction between each hybrid and the related parental lines for the traits analyzed. This comprehensive approach used, allow to dissect those traits which can be successfully introgressed in hybrids and are useful for precision breeding of novel varieties. [ABSTRACT FROM AUTHOR]

Thirteen apple cultivars were analyzed for their total phenolic content, total flavonoids, anthocyanins, ascorbic acid in methanolic extracts of both peel and cortex fractions. Three in vitro assays (FRAP, DPPH, and CUPRAC) were used to determine the antioxidant activity. Concentration of the phytochemicals studied varied greatly between the apple peel and the cortex region. Peels showed ~ 2.8 times higher total phenolic content and ~ 2.68% higher flavonoid content than the cortex. Principal component analysis could successfully explain 76.86% and 84.27% variability in the antioxidant determinants (antioxidants/assays) in the peel and cortex region of apple cultivars, respectively. Major contributor for antioxidant activity in both apple peel and cortex was total flavonoid content. Cultivars 'Well Spur' and 'Oregon Spur II' were found to be substantially rich in these two antioxidants. The antioxidant activity was best expressed by the in vitro FRAP assay in both the fractions. Non-hierarchical K-medoids clustering reflected the presence of an antioxidant/ assay protocol apart from the antioxidant/assay we considered in this study that needs further exploration to get full spectra of antioxidant profile across apple genotypes. Based on multivariate analysis and the concept of RACI, the FRAP antioxidant assay is recommended for determining antioxidant activity in apples. [ABSTRACT FROM AUTHOR]

Ascorbic acid-2-phosphate (A2-P) is an oxidation-resistant derivative of ascorbic acid that has been widely employed in culturing adipose-derived stem cells (ASCs) for faster expansion and cell sheet formation. While high dose ascorbic acid is known to induce cellular apoptosis via metabolic stress and genotoxic effects, potential cytotoxic effects of A2-P at high concentrations has not been explored. In this study, the relationship between ASC seeding density and A2-P-induced cytotoxicity was investigated. Spheroid-derived ASCs with smaller cellular dimensions were generated to investigate the effect of cell-cell contact on the resistance to A2-P-induced cytotoxicity. Decreased viability of ASC, fibroblast, and spheroid-derived ASC was noted at higher A2-P concentration, and it could be reverted with high seeding density. Compared to control ASCs, spheroid-derived ASCs seeded at the same density exhibited decreased viability in the A2-P-supplemented medium. The expression of antioxidant enzymes (catalase, SOD1, and SOD2) was enhanced in ASCs at higher seeding densities. However, their enhanced expression in spheroid-derived ASCs was less evident. Furthermore, we found that co-administration of catalase or N-acetylcysteine nullified the observed cytotoxicity. Collectively, A2-P can induce ASC cytotoxicity at higher concentrations, which can be prevented by seeding ASCs at high density or co-administration of another antioxidant. [ABSTRACT FROM AUTHOR]

Juices from nine new late-season triploid mandarins (Tania-46 (1), Tania-47 (2), Omet (3), Albir (4), Tania-48 (5), Tania-43 (6), Tania-44 (7), Coral (8), and Matiz (9), and from their parents were analyzed for mainly internal quality attributes, vitamin C, total phenolics, flavonoids, phenolic, and organic acids. Antioxidant activity was measured by three methods, the DPPH free radical-scavenging assay, ferric reducing antioxidant power (FRAP) test, and ABTS analysis. All the new hybrids exhibited high internal and nutritional quality which may be considerate rich sources of phytochemicals. Among the nine varieties, Tania-48 hybrid was shown to be the richest in vitamin C, flavanones (hesperidin, eriocitrin, and neoeriocitrin), polymethoxyflavones, and malic and succinic acids. Furthermore, the juice of this new triploid hybrid displayed high antioxidant capacity which may make it important for human diet as a source of health-promoting components. On the other hand, Tania-44, Tania-48, and Tania-43 fruit juices exhibited greater content of eriocitrin and neoeriocitrin than the others. [ABSTRACT FROM AUTHOR]

Vitamin C is one of the most abundant exogenous antioxidants in the cell, and it is of the utmost importance to elucidate its mechanism of action against radicals. In this study, the reactivity of vitamin C toward OH and $$ {HO}_2/{O}_2^{-} $$ radicals in aqueous medium was analyzed by ab initio molecular dynamics using CPMD code. The simulations led to results similar to those of static studies or experiments for the pair of $$ {HO}_2/{O}_2^{-} $$ radicals but bring new insights for the reactivity with hydroxyl radical: the reaction takes place before the formation of an adduct and consists of two steps: first an electron is transferred to hydroxyl radical and then the ascorbyl radical loses a proton. [ABSTRACT FROM AUTHOR]

Background/objectives: Epidemiologic evidence on the relationship between antioxidant vitamin intake and stroke is limited. We aimed to investigate the association between dietary intake of antioxidant vitamins and the incidence of total stroke and ischemic stroke.Subjects/methods: The subjects were 82 044 Japanese men and women aged 45-74 years under the Japan Public Health Center-based Prospective Cohort Study. Between 1995 and 1997, dietary assessment was done using a food frequency questionnaire. During 983 857 person-years of follow-up until the end of 2009 we documented 3541 incident total strokes and 2138 ischemic strokes.Results: Dietary intakes of α-carotene, β-carotene, α-tocopherol and vitamin C were not inversely associated with the incidence of total stroke and ischemic stroke adjustment for cardiovascular risk factors and selected lifestyle variables. When stratified by current smoking status, the inverse association between dietary vitamin C intake and incidence of total stroke observed among non-smokers but not smokers, with respective multivariable hazard ratios for the highest versus lowest quintiles of vitamin C of 0.81 (95% confidence interval (CI), 0.68-0.96; P-trend=0.03) among non-smokers; and 1.03 (0.84-1.25; P-trend=0.55) among smokers. As for ischemic stroke, the corresponding multivariable hazard ratios were 0.76 (0.60-0.96; P-trend=0.02) among non-smokers; and 1.00 (0.78-1.28; P-trend=0.61) among smokers.Conclusions: Dietary vitamin C intake was inversely associated with the incidence of total stroke and ischemic stroke among non-smokers. [ABSTRACT FROM AUTHOR]

Ternary mixtures of lecithins, vitamin C and vitamin E are powerful antioxidants for the stabilization of polyunsaturated (n-3 fatty acid) oils. In this study, the chemistry of the antioxidant synergistic effect was investigated in ethyl linoleate (EL) containing α-tocopherol (α-Toc) or in linoleate rich vegetable oils at 110 °C using mixtures of phosphatidylethanolamine (PE) and either l-ascorbic acid (AA) or l-dehydroascorbic acid (DHA). The highest stabilization effects in EL were similar in both systems and were found in the molar mixtures of PE and AA or DHA. The thermal formation of reaction products between PE and AA (PE-AA) or DHA (PE-DHA) were investigated by HPTLC/ESI-MS. When α-tocopherylquinone (α-TQ) was used instead of α-Toc, nearly the same antioxidant effect was observed in the EL system. It was shown that molar mixtures of PE and AA, or PE and DHA, can regenerate α-TQ to α-Toc at elevated temperatures. PE-AA was synthesized and tested as antioxidants in EL containing α-Toc and in vegetable oils at room temperature. An improved stabilization was observed with the synthesized derivative compared to the physical mixture of the compounds, which demonstrated that PE-AA is a potential new antioxidant. A mechanism for the synergistic action between PE, AA and α-Toc through an acid-catalysed regeneration of α-TQ is suggested. PE-AA is an active apolar antioxidant, which is involved in the reduction of α-TQ. [ABSTRACT FROM AUTHOR]

Background/objectives: Antioxidants and polyunsaturated fatty acids (PUFAs) have a role in the human immune defense and may affect the susceptibility to upper respiratory tract infection (URTI). To examine dietary intake of vitamin C, vitamin E, selenium, zinc and PUFAs in relation to URTI incidence in a prospective cohort study.Subjects/methods: A total of 1533 Swedish women and men aged 25-64 years were followed for nine months during 2011-2012. Information on dietary intake was assessed through a web-based food frequency questionnaire, and events of URTI were self-reported prospectively as they occurred. Cox proportional hazards regression was applied to obtain incidence rate ratios with 95% confidence intervals.Results: The mean number of URTI events was 0.9 among all participants, 1.0 among women and 0.7 among men. In women, the incidence rate ratios (95% confidence interval) for high compared with low intake were 0.69 (0.55-0.88) for vitamin C, 0.77 (0.62-0.96) for vitamin E, 0.57 (0.39-0.83) for docosahexaenoic acid (DHA) and 0.80 (0.65-0.99) for arachidonic acid (AA). No association was found for selenium or zinc among women. In men, an increased URTI incidence was seen with medium vitamin E intake (1.42 (1.09-1.85)) and high zinc intake (1.50 (1.04-2.16)). No association was found for vitamin C, selenium or PUFAs among men.Conclusions: We found an inverse association of URTI incidence among women for vitamin C, vitamin E, DHA and AA intake and a positive association among men for vitamin E and zinc intake. The observed gender differences warrant further investigation. [ABSTRACT FROM AUTHOR]

Aims and Objectives: This study was undertaken in order to study the combined effect of vitamin C and E supplements during pregnancy on the incidence of preeclampsia and to study its effect on neonatal outcome. Materials and Methods: This study was conducted in Goa Medical College, from March 2010 to June 2011. Cases and controls were taken randomly from antenatal patients attending our hospital OPD. The study group included 200 pregnant women in second trimester (13 weeks onwards) and third trimester of pregnancy. Cases included 100 women who receive oral vitamin C in dose 500 mg and oral vitamin E in dose of 400 IU per day. Control group included 100 women who did not receive vitamin E and vitamin C. All women were advised not to take any other multivitamin supplements. Conclusion: The incidence of preeclampsia in this study was 7 % in cases and 13 % in controls. Twenty out of the total 200 antenatal patients had developed preeclampsia. There was a 46 % risk reduction in the incidence of preeclampsia in cases as compared to controls. The incidence of severe preeclampsia in cases was 2 % and in controls was 7 %. This result showed 72 % reduced risk in the development of severe preeclampsia in cases as compared to controls. The study showed that significant number of antenatal patients developed preeclampsia in the age group 25-30 years, more so in controls. Primigravidas were at greater risk of developing preeclampsia than multigravidas in our study. The primigravidas in control group showed 36 % increased risk of developing preeclampsia as compared to cases. Out of 20 patients, 6 of them developed preeclampsia before 34 weeks and 14 patients developed preeclampsia after 34 weeks. There were more preterm deliveries in non-vitamin group as compared to vitamin-supplemented group. There was 46 % reduced risk in occurrence of preterm deliveries in vitamin-supplemented group, and this result was statistically significant. There was 50 % reduction in risk of stillbirths and neonatal deaths in vitamin-supplemented group, but this result was not statistically significant. The incidence of neonatal admissions was 10 % in cases and 16 % in controls. Hence, it is seen that there was 53 % reduced risk of neonatal admissions in cases, and this result was statistically significant. Controls were 1.26 times more prone for LSCS as compared to cases. Hence, we recommend routine vitamin C and E intake in all pregnant women, starting from 13 weeks of pregnancy onwards till delivery. [ABSTRACT FROM AUTHOR]

Background/objectives: The objective of this study was to conduct a method comparison of a modified food frequency questionnaire (FFQ), designed to estimate usual dietary intake of selected micronutrients and antioxidants including folate, choline, betaine, vitamin C and carotenoids (α-carotene, β-carotene, lutein, lycopene and β-cryptoxanthin) with 24-h dietary recalls (24-HR) in women of reproductive age.Subjects/methods: Sixty-four British women of reproductive age (18-40 years) were recruited in Oxford, UK and provided complete dietary data for analysis.Methods: We compared micronutrient estimates from the FFQ against estimates derived from three multiple-pass, 24-HR interviews, by evaluating Pearson's correlation coefficients and Bland-Altman plots.Results: Median intakes of most nutrients were higher when measured by FFQ compared with 24-HR. Strong correlation coefficients were observed for folate (r=0.80) and choline (r=0.68), whereas moderate correlation coefficients were observed for vitamin C (0.50) and lycopene (0.43). Weak correlation coefficients were observed for betaine (0.39) and other carotenoids (r=0.26-0.38). Bland-Altman plots indicated that there was a large amount of variability in the FFQ estimates of nutrient intakes compared to those using 24-HR, particularly for carotenoids.Conclusions: The findings indicate that this FFQ estimated higher mean intakes for most nutrients. Pearson's correlation coefficients were comparable with previous research; however, the Bland-Altman plots suggest a high variability in mean nutrient estimates between the FFQ and 24-h. We recommend further investigation of the validity of this FFQ before use. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Objectives: To compare the effects of lotus root and cucumber on antioxidant function in aged subjects. Design: Pilot comparative study. Setting: Research setting with vegetable intervention. Participants: Healthy aged subjects over the age of sixty. Intervention: 30-day supplementation of lotus root or cucumber powder. Measurements: Plasma value of ferric reducing antioxidant power assay, activity of antioxidant enzymes, contents of some antioxidants, oxidation products, hemolysis, blood mononuclear cell DNA damage and urinary excretion of 8-hydroxy-2'-deoxyguanosine were measured before and after the intervention. Results: Plasma glutathione peroxidase activity, contents of vitamin C, total phenolics were significantly increased, while plasma uric acid content significantly decreased in both groups at the end of the intervention. Meanwhile, hemolysis was significantly reduced in both groups and DNA injury rate of blood mononuclear cells in lotus root group and the ratio of comet tail length to total length in cucumber group were also declined significantly post-intervention. However, plasma value of ferric reducing antioxidant power assay, contents of reduced glutathione, vitamin E, malondialdehyde, oxidized low density lipoprotein, carbonyls and activity of superoxide dismutase and catalase were not changed significantly in both group after the intervention. Conclusion: These results suggest that lotus root and cucumber are not remarkably different in improving antioxidant function in aged subjects, though they are significantly different in antioxidant capacity in vitro. The benefits observed in this study may come from the additive or synergistic combinations of antioxidants contained in vegetables. [ABSTRACT FROM AUTHOR]

Purpose: The present study was designed to test the hypothesis that long-term treatment with hydrogen-rich saline abated testicular oxidative stress induced by nicotine in mice. Methods: The effects of hydrogen-rich saline (6 ml/kg, i.p.), vitamin C (60 mg/kg, i.p.) and vitamin E (100 mg/kg, i.p.) on reproductive system and testicular oxidative levels in nicotine-treated (4.5 mg/kg, s.b.) mice were investigated. Results: It was found that vitamin C and vitamin E attenuated serum oxidative level, but did not lower testicular oxidative levels in mice subjected to chronic nicotine treatment, and did not improve the male reproductive damage and apoptosis induced by nicotine. Different from normal antioxidants, vitamin C and vitamin E, hydrogen-rich saline abated oxidative stress in testis, and protected against nicotine-induced male reproductive damages. Conclusion: Our results first demonstrated that long-term treatment with hydrogen-rich saline attenuated testicular oxidative level and improved male reproductive function in nicotine-treated mice. [ABSTRACT FROM AUTHOR]

The present research was aimed to compare the traditional white vinification with a combined cryomaceration-vinification in reductive conditions, by evaluating their effects on chemical and physical indices and on antioxidant compounds of 'Falanghina' and 'Bombino bianco', two wine grape cultivars of southern Italy. According to the results, the two cultivars showed similar behaviour in response to the same vinification protocol. The processing conditions mainly affected physico-chemical characteristics such as titratable acidity, pH, SO, tartaric and malic acids, phenolic concentrations, and antioxidant activity. Titratable acidity decreased with cryomaceration due to the tartrate precipitation, whereas the malic acid was greatly extracted from pulps and skins. In the reductive conditions applied, the SO was protected by the presence of ascorbic acid; thus, the wines exhibited higher free/total SO ratio. Cryomaceration combined with vinification in reductive conditions allowed a greater extraction of phenolic compounds from skins and, consequently, a greater antioxidant activity compared to the traditional winemaking. This behaviour was due to both the protection exerted by the low temperatures and the solubilisation of proanthocyanidins and flavans reactive with vanillin favoured by the high free SO content. [ABSTRACT FROM AUTHOR]

A colorimetric assay method is described for the environmental detection of 2-mercaptobenzimidazole (MBI) using surface plasmon resonance of gold nanoparticles (AuNPs). Stable and dispersed AuNPs with intensified plasmon resonance were prepared in situ using a simple, rapid, and eco-friendly procedure by applying ascorbic acid as a reducer and cetyltrimethylammonium bromide as a stabilizer. The presence of MBI has a strong effect on the plasmon absorbance of AuNPs, which was employed for the detection of MBI. The calibration curve was linear in the range of 1.0 × 10-5.5 × 10 mol/L of MBI; the detection limit was 8.4 × 10 mol/L. The relative standard deviations for eight replicate measurements of 3.0 × 10 and 5 × 10 mol/L MBI were 3.9 and 1.4 %, respectively. The method was successfully applied to the determination of MBI in tap, river, sea, and heat exchanger cooling water samples. [ABSTRACT FROM AUTHOR]

Background: The theoretical, but especially the practical values of identifying the biochemical compounds from the Rosa canina L. fruits are of present interest, this aspect being illustrated by the numerous researches. It was reported that the Rosa canina L. fruit, with its high ascorbic acid, phenolics and flavonoids contents, have antioxidant, antimutagenic and anticarcinogenic effects. This study was performed on order to evaluate the amount of the main phytochemicals (vitamin C, total polyphenols, and total flavonoids) content and their antioxidant activity. Results: The results obtained revealed that the average amounts of vitamin C within the studied genotypes were: 360.22 mg/100 g frozen pulp (var. transitoria f. ramosissima, altitude 1250 m) and 112.20 mg/100 g frozen pulp (var. assiensis, altitude 440 m), giving a good correlation between the vitamin C content of the rosehip and the altitude. The total polyphenols content varied from 575 mg/100 g frozen pulp (var. transitoria f. ramosissima) to 326 mg/100 g frozen pulp (var. lutetiana f. fallens). The total flavonoids content showed the highest value for var. assiensis variant 163.3 mg/100 g frozen pulp and the lowest value attributed to var. transitoria f. montivaga 101.3 mg/100 g frozen pulp. The antioxidant activity of eight rose hip extracts from wild Transylvania populations was investigated through DPPH method. The antioxidant activity revealed a good correlation only with vitamin C content and total polyphenols. Conclusion: Eight Rose hip fruit species were compared taking into consideration the ascorbic acid, total polyphenols, total flavonoids contents and their antioxidant activity. Based on these results, two of the rosehip genotypes that were analysed could be of perspective for these species' amelioration, due to their content of phytochemicals mentioned above. These varieties are var. transitoria f. ramosissima (Bistrita-Nasaud, Agiesel) and var. transitoria f. montivaga (Bistrita-Nasaud, Salva) which can be used as a potential source of natural antioxidants. [ABSTRACT FROM AUTHOR]

Molecules acting as antioxidants capable of scavenging reactive oxygen species (ROS) are of utmost importance in the living cell. Vitamin C is known to be one of these molecules. In this study we have analyzed the reactivity of vitamin C toward the $$ \cdot OH $$ and $$ \cdot OOH $$ ROS species, in all acidic, neutral and basic media. In order to do so, density functional theory (DFT) have been used. More concretely, the meta-GGA functional MPW1B95 have been used. Two reaction types have been studied in each case: addition to the ring atoms, and hydrogen/proton abstraction. Our results show that $$ \cdot OH $$ is the most reactive species, while $$ \cdot OOH $$ displays low reactivity. In all three media, vitamin C reactions with two hydroxyl radicals show a wide variety of possible products. [ABSTRACT FROM AUTHOR]

Background D-isoascorbic acid is a food antioxidant additive and used in accordance with Good Manufacturing Practice (GMP). High solubility in water (about 150 g/L at 25°C) reduces its effectiveness in stabilizing fats and oils. Our research group had successfully synthesized Disoascorbyl palmitate using immobilized lipase Novozym 435 as a biocatalyst. Low production efficiency of D-isoascorbyl palmitate is still a problem for industrial production due to the long reaction time of over 24 h. In the present work, ultrasonic treatment was applied for accelerating the reaction process. The operation parameters were optimized to obtain the maximum D-isoascorbyl palmitate conversion rate by using a 5-level-4-factor Central Composite Design (CCD) and Response Surface Methdology (RSM). The reaction apparent kinetic parameters under the ultrasound treatment and mechanical shaking conditions were also determined and compared. Results Results showed that ultrasound treatment decreased the reaction time by over 50%. Disoascorbyl palmitate yielded to 94.32 ± 0.17% and the productivity reached to 8.67 g L-1 h-1 under the optimized conditions as: 9% of enzyme load (w/w), 61°C of reaction temperature, 1:5 of D- isoascorbic-to-palmitic acid molar ratio, and 137 W of the ultrasound power. The immobilized lipase Novozym 435 could be reused for 7 times with 65% of the remained Disoascorbyl palmitate conversion rate. The reaction kinetics showed that the maximum apparent reaction rate ( max v ) of the ultrasound-assisted reaction was 2.85 times higher than that of the mechanical shaking, which proved that ultrasound treatment significantly enhanced the reaction efficiency. Conclusion A systematic study on ultrasound-assisted enzymatic esterification for D-isoascorbyl palmitate production is reported. The results show a promising perspective of the ultrasound technique to reduce the reaction time and improve the production efficiency. The commercial D-isoascorbyl palmitate synthesis will be potentially realized due to this ultrasound-promoted esters synthesis method. [ABSTRACT FROM AUTHOR]

Different methods that are used to measure peroxyl radical (ROO) scavenging capacity were used in model systems containing four common antioxidant compounds: ascorbic acid, cysteine, gallic acid and Trolox, a water-soluble vitamin E analogue. Five tests were performed, with differences in the method of peroxyl radical generation (lipoxygenase, azo-compound thermal degradation and spontaneous oxidation from a natural source of fatty acids) and in the addition of probes such as linoleic acid, crocin, fluorescein and electron paramagnetic resonance (EPR) by spin-trapping with α-phenyl- N- tert-butyl-nitrone. Significant differences were found in antioxidant reactivity, evaluated by dose-effect semi-logarithmic plots and EC50 values, and a possible explanation for these differences was explored. In assays in which ROO was generated by the azo-compound or spontaneous oxidation, gallic acid was the most powerful antioxidant. When lipoxygenase was used to produce ROO, ascorbic acid had the highest scavenging index, while cysteine and gallic acid had low levels of activity. Another difference was identified regarding the molecular probe: ascorbic acid and Trolox were the least reactive in the EPR system and azo-bis system with fluorescein, while in assays with crocin, these compounds had intermediate activities. Ascorbic acid and Trolox were the best antioxidants in an enzymatic-linoleic acid system, with a reciprocal ratio of 6:1, while adding crocin to the same system changed the reciprocal ratio to 2:1. A literature examination indicated that out of the antioxidant compounds tested, cysteine has the highest bond dissociation enthalpy, and this compound showed, as expected, low scavenging activity in three of the five tests in this study. [ABSTRACT FROM AUTHOR]

Phospholipids synergistically enhance the antioxidant effect of phenolic antioxidants. Mixtures of lecithins, ascorbic acid and tocopherols are known as strong antioxidants. In our study, the mechanism of the synergistic effect of phospholipids with tocopherols was investigated. The oxidative deterioration and the degradation of tocopherols were analyzed in degummed rapeseed oil or in mixtures with ethyl linoleate at 25 or 110 °C. It was shown that lecithins reduce the degradation of tocopherols in rapeseed oil or in ethyl linoleate model system at 25 or 110 °C. It was found that phosphatidylethanolamine (PE) and phosphatidylserine (PS) can regenerate α-tocopheryl quinone (α-TQ) to α-tocopherol at elevated temperatures. The regeneration could be catalyzed by acetic acid. The synergistic effect of PE or PS with α-tocopherol and l-ascorbic acid resulted from the regeneration of α-TQ to α-tocopherol, because PE, l-ascorbic acid and α-tocopherol show the same stabilization effect upon ethyl linoleate as PE, l-ascorbic and α-TQ. Phosphatidylcholine as a non-amine phospholipid does not regenerate α-TQ. However, it improves the regeneration of α-tocopherol from α-tocopheroxyl radicals with l-ascorbic acid in ethyl linoleate through its ability to acts as a phase transfer catalyst between the polar l-ascorbic acid and the unpolar α-tocopheroxyl radicals. A mechanism for the regeneration of α-TQ by PE or PS is suggested. The activation of α-TQ by PE or PS and the formation of α-tocopherones are the key steps of the mechanism. [ABSTRACT FROM AUTHOR]

The present study was carried out to evaluate the effect of environmental factors (air and UV-C irradiation) on various common fruits juices (lemon, orange, papaya and grape). Total phenolics, total ascorbic acid (AA) content and antioxidant capability were determined in atmospheric air oxidation on fresh fruit juices, and the effect of UV-C irradiation on AA was investigated in both fresh fruit juices and commercial AA using RP-HPLC. The total phenolics content was found to be 92.46 ± 1.5, 41.53 ± 2.1, 138.56 ± 2.3 and 110.54 ± 3.9 mg/100 ml of lemon, orange, papaya and grape juices, respectively. DPPH radical-scavenging activity of the fresh juices was 94.53 ± 3.1, 82.36 ± 2.2, 94.65 ± 3.5 and 90.74 ± 2.6 percentage, whereas the 1-day-old fruit juices showed reduced scavenging activity when compared to fresh juices. Total phenolic (TP) and DPPH-scavenging activity were significantly decreased in the mean at P < 0.05 level. Ascorbic acid (vitamin C) content of fresh fruit juices was determined through RP-HPLC; fruit juices that were kept in open container for 24 hrs and that were treated with UV irradiation have shown a decrease in AA content, when compared with control fresh juice samples. AA degradation increased with high significant differences at P < 0.001 level, with the increase in oxidation time in atmospheric air and UV-C radiation. [ABSTRACT FROM AUTHOR]

We evaluated the role of total dietary antioxidant capacity and of individual antioxidants on endometrial cancer risk in a population-based case-control study in New Jersey, including 417 cases and 395 controls. Dietary intake was ascertained using a food-frequency questionnaire (FFQ), and total antioxidant capacity (TAC) intake was estimated using the USDA Oxygen Radical Absorbance Capacity (ORAC) database and the University of Oslo's Antioxidant Food Database (AFD) and FFQ-derived estimates of intake. Odds ratios and 95 % confidence intervals were derived using multivariate logistic regression controlling for major endometrial cancer risk factors. Using the ORAC database, after adjusting for major covariates, we found decreased risks for the highest tertile of total phenolic intake compared with the lowest (OR: 0.62; 95 % CI: 0.39-0.98). There was no association for TAC intake based on the AFD, which utilized the ferric-reducing ability of plasma (FRAP) assay to assess antioxidant capacity. There was no strong evidence for an association with intake of any of the individual antioxidants. Our findings suggest that total phenolic consumption may decrease endometrial cancer risk. [ABSTRACT FROM AUTHOR]

Abstract: The goal of this study is to investigate the ability of vitamin E in the active form α-tocopherol to mitigate the ethanol induced damaging effects and malformations in the developing chick embryo. Fertilized eggs were divided into five groups; the control group, and treated groups. The experimental groups were injected, in the air sac, before incubation with a single dose of 100μl saline solution, 100μl of 10% ethanol in saline solution, a mixture of 100μl of 10% ethanol and 200ppm vitamin E or 10% ethanol and 400ppm vitamin E. Treatment of developing chick embryos with 10% ethanol resulted in growth retardation and malformations in the eye, brain, limbs and other body parts. Ethanol exerted its degenerative effects probably via increasing membrane fluidity leading to membrane damage and significantly increased levels of lipid peroxidation. Ethanol also induced significant reduction in nitric oxide levels resulting in reduced body weight of the treated embryo probably due to restricted bold flow. Ethanol significantly increased glutathione level as a defense response. Vitamin C levels were significantly decreased after ethanol treatment due to oxidation or utilization. Vitamin E in the active form α-tocopherol partially mitigated the ethanol damaging effects either by exerting its antioxidant properties leading to a significant reduction of lipid peroxidation levels, retaining normal levels of nitric oxide or maintaining normal levels of endogenous antioxidants, glutathione and vitamin C. [Copyright &y& Elsevier]

Objective: To measure the oxidative and antioxidant biochemical parameters in the serum of Chinese patients with age-related macular degeneration (AMD) and in a similar age control group from the same area. Design: A case-control study. Participants: 56 AMD patients (21 early dry, 13 geographic atrophy and 22 wet form) and 34 normal subjects, similar for age and sex were studied. Measurements: Both groups completed a questionnaire about demographic characters and dieatry habit, and the levels of serum lipid peroxidation (malondialdehyde, MDA) and antioxidants parameters (vitamin C and E, the activities of superoxide dismutase-SOD, total antioxidant capacity - TAC) were determined. Results: There was a significantly higher frequency of daily intake of fruit and legumes in controls than in AMD patients. There was a significantly increased serum MDA levels and SOD activities, and significantly decreased serum vitamin C and total antioxidant capacity in AMD patients as compared to controls. The intensity of lipid peroxidation was higher with the progression of AMD. There was not difference in serum vitamin E levels between AMD patients and controls. Conclusion: Oxido-reduction disturbance may be involved in the pathogenesis of AMD. There is a significantly decreased antioxidant capacity in AMD patients. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of aerobic training in the context of antioxidant supplementation on systemic oxidative stress and leukocytes heat shock protein (Hsp)72 expression in the elderly. Design: Sixteen septuagenarians (8 males and 8 females, mean age 74.6) were supplemented with Vitamin C and E (respectively 500 and 100mg per day) and randomly assigned either to sedentary (AS) or individualized aerobically trained (AT) group for 8 weeks. Methods: Plasma Vitamin C and E concentrations and aerobic fitness, as well as resting and post graded exercise (GXT) Hsp72 expression in leukocytes, plasma levels of thiobarbituric acid reactive substances (TBARS) and advanced oxidation protein product (AOPP) were measured pre and post training / supplementation. Results: At the end of the intervention, the two groups showed a significant increase in resting plasma vitamin C and E (approximately 50 and 20% increase respectively) and a significant decrease in both resting and post GXT plasma TBARS and AOPP (approximately 25 and 20% decrease respectively). These changes were of similar magnitude in the two groups. The reduced oxidative stress was concomitant with a 15% decreased expression of Hsp72 in monocytes and granulocytes in both groups. Conclusion: This study provides evidence that in elderly, increased concentration of antioxidant vitamins C and E is associated with a reduction in oxidative stress and leukocytes Hsp72. In this context, 8 weeks of aerobic training has no impact on oxidative stress or leukocytes Hsp72 expression in elderly people. [ABSTRACT FROM AUTHOR]

The article discusses a study conducted to assess antioxidant properties and color changes in low-sugar bilberry jam during the processing, storage and pectin concentration. It has been informed that study results found that thermal processing induce significant alterations in fresh fruits that includes loss of total monomeric anthocyanins (TMA), L-ascorbic acid (L-AsAc) content, total phenolics (TP) content and ferric reducing antioxidant power (FRAP) values. It has been stated that the study suggested that bilberry jams is a good source of antioxidant compounds, but important losses occur during processing of fruits.

The influence of harvesting date on some physicochemical properties of nectarine (Prunus persica var. Red gold) fruit including fruit weight, pigment content, total carbohydrate, total phenol and antioxidant activity were studied. Fruits were harvested in four different stages; a) two weeks after fruit set, b) pit hardening, c) three weeks after pit hardening and 6 weeks after pit hardening. Results showed that the heaviest fruit either wet or dry was observed in the last harvesting date. The reduction in sucrose at the final harvest might be due to conversion to monosaccharides like fructose or glucose. On the other hand, although the content of total phenolic and flavonoid content of fruits were significantly reduced in the last harvest, no significant reduction was observed in their antioxidant activity. Generally, it can be concluded that compounds like anthocyanin, carotenoids and vitamin C play important role in antioxidant activity in ripened nectarine fruit and their content differ in different harvest times. [ABSTRACT FROM AUTHOR]

Rice ( Oryza sativa L.) is sensitive to prolonged exposure to low temperature, which at the seedling stage can result in significant chilling injury and mortality. The objective of this study was to quantify physiological and biochemical changes in rice seedlings undergoing chilling stress and compare those changes with visual evaluation of tolerance. Seedlings from the cultivars M-202 (tolerant) and IR50 (sensitive) were subjected to 9°C for 14 days in a controlled environment chamber. Leaf tissues were harvested at various time points for determination of electrolyte leakage, proline, malondialdehyde, ascorbic acid and reduced glutathione. Significant differences between M-202 and IR50 were detected in electrolyte leakage, proline, and ascorbic acid starting at 7 days with IR50 exhibiting higher levels of these indicators. Most IR50 seedlings were dead at 14 days. A set of fifty rice accessions including M-202 and IR50 was evaluated at 10 days of cold treatment to examine the correlation of visual ratings with the physiological indices. Visual ratings were most highly correlated with electrolyte leakage and least correlated with proline content. Based on visual ratings and the physiological indices, we identified several cultivars that outperformed M-202 in cold tolerance while IR50 had the lowest tolerance of the cultivars tested. [ABSTRACT FROM AUTHOR]

procedure is developed for the photometric determination of ascorbic acid in drug preparations. It is based on the rapid and highly selective reaction of ascorbic acid with a novel reagent, the guanidinium salt of 1-bismuto-11-molybdophosphoric heteropolyacid. The detection limit for ascorbic acid in stepwise injection analysis makes 15 mg/L, and the duration of single analysis, 5 min. [ABSTRACT FROM AUTHOR]

Tea seed is believed to be recalcitrant based on its sensitivity to chilling or drying stress. Reactive oxygen species (ROS) and alterations in cytosolic redox status have been implicated in intolerance to desiccation by recalcitrant seed, but there is little information available regarding how ROS are regulated in seeds susceptible to drying stress. We investigated changes in protein expression and activity in tea embryo in response to desiccation using physiological and proteomic methods. Results showed that desiccation treatment dramatically induced the accumulation of HO in tea embryos, accompanied by increased activities of antioxidant enzymes like ascorbate peroxidase (APX) and superoxide dismutase (SOD). Proteomic analyses also demonstrated that 23 proteins associated with defense response, metabolism and redox status were up-regulated following desiccation. Increase in antioxidants, ascorbic acid (AsA) and catalase (CAT) (HO scavengers) partially assuaged desiccation damage to tea seed, resulting in improved germination rates. Higher accumulation of HO aggravated desiccation damage to seeds leading to lower germination activity. We propose that desiccation causes an over-accumulation of ROS that are not efficiently scavenged by increased levels of antioxidant enzymes. High levels of ROS alter the redox status and are detrimental to seed viability. Reducing ROS to appropriate concentrations is an efficient way to reduce desiccation damage and improve germination rates of recalcitrant seeds. [ABSTRACT FROM AUTHOR]

Background: 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.Methods: 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.Results: 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.Conclusion: 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. [ABSTRACT FROM AUTHOR]

The aim of the present analysis was to study the influence of the sample concentration on the measured antioxidant capacity, since such investigations are scarce but necessary to ensure the reproducibility of the results. Pure substances (ascorbic acid, gallic acid, Trolox®, uric acid) and food extracts (strawberry nectar, tomato extract, white tea) were analysed using seven common antioxidant capacity assays (three versions of Trolox equivalent antioxidant capacity, TEAC; ferric reducing antioxidant power, FRAP; photochemiluminescence, PCL; oxygen radical absorbance capacity, ORAC and total phenolics assay). For all applied pure substances and in most of the assays effects of the sample concentration on the measured antioxidant capacity were observed. Since it remains speculative how sample concentration does affect the measured antioxidant capacity exactly, it is strongly recommended to use at least three sample concentrations for analysis to detect and to discuss concentration-dependent effects. [ABSTRACT FROM AUTHOR]

Ají ( Capsicum baccatum L.) and rocoto ( C. pubescens R. & P.) are two Capsicum pepper species native to the Andean region that have not been subjected to intensive breeding. However, the increase in its demand in European markets has sparked the development of breeding programmes for adaptation to Mediterranean climates, which include breeding for higher levels of bioactive compounds. We have studied the composition of red and yellow carotenoids ( CR and CY, respectively), ascorbic acid (AA), and total phenolics (TP) in 34 accessions of Capsicum, including 23 of C. baccatum, eight of C. pubescens, and 3 controls of C. annuum, which were grown in Spain both under greenhouse (GH) and open field (OF) conditions. The results show that in both growing conditions C. baccatum presents a considerable variation for most of the traits studied, with several accessions having similar or higher levels than C. annuum for the compounds studied. This indicates that C. baccatum is an important source of antioxidant compounds with nutritional value. On the contrary, C. pubescens had a poor performance, with low levels for all the compounds studied, and a poor adaptation to the conditions of Mediterranean climates. When considering the GH or OF growing cycles separately, heritability values were high (>0.75) for CR, CY and AA, and moderate (0.42 for GH and 0.62 for OF) for TP. The existence of an important genotype × environment interaction resulted in lower levels for heritability when considering both growing cycles together, although the values were still high for CR and AA (>0.6). Positive significant genotypic correlations among all the traits studied were found, except for TP with CR and AA in the OF cycle. This information indicates that there are good prospects for developing C. baccatum varieties with higher levels of bioactive compounds. [ABSTRACT FROM AUTHOR]

The effect of different decontamination treatments such as washing with sodium hypochlorite (20 and 200 mg/L), peroxyacetic acid (80 and 250 mg/L), neutral electrolysed oxidising water (4.9 and 31.7 mg/L free chlorine) and contact with 1.55 mg/L chlorine dioxide gas on the microbial and sensory quality, and the nutrient content of fresh-cut white cabbage was studied. Only rinsing with 200 mg/L sodium hypochlorite, peroxyacetic acid or contact with gaseous chlorine dioxide resulted in significantly higher reductions of the total plate count (1.5–2.5 log cfu/g) than the ones achieved by washing with tap water (0.5 log cfu/g). However, those treatments giving the best results from a microbial point of view induced significant changes in the sensory quality. Regarding the effects on nutrient content, the mechanical effects caused by water washing already reduced the vitamin C content by 16–29%. Contrary to washing with neutral electrolysed oxidising water and contact with chlorine dioxide gas, a supplementary decrease of the vitamin C content ranging between 9 and 28% was observed, when peroxyacetic acid or 200 mg/L sodium hypochlorite were used. After the use of peroxyacetic acid or gaseous chlorine dioxide, the phenol content also showed a decreasing trend, although not statistically significant. Apart from the effect of washing with water, the lipophilic nutrients were well retained after a decontamination step except for the α-tocopherol content, when peroxyacetic acid was used (−43 to 56%), and for the all-trans-β-carotene content (−8%) of cabbage in contact with gaseous chlorine dioxide. Because of its potential to reduce the initial microbial load without negative effects on the sensory quality, in combination with its limited effects on nutrient content, a treatment with 80 mg/L peroxyacetic acid is preferable to decontaminate fresh-cut white cabbage. [ABSTRACT FROM AUTHOR]

Antioxidant vitamins may reduce cancer risk by limiting oxidative DNA damage. To summarize and quantify the current epidemiologic evidence of an association between antioxidant vitamin intake and endometrial cancer, we conducted a systematic literature review and meta-analysis. One cohort and 12 case-control studies presenting relevant risk estimates were identified by conducting bibliographical searches through June 2008. Dose-response meta-analyses were conducted for beta-carotene, vitamin C, and vitamin E from food sources. Intake from supplements was not considered in the meta-analyses because of the few studies that reported relevant information. Based on case-control data, the random-effects summary odds ratios (OR) were, for beta-carotene: 0.88 (95% CI: 0.79-0.98) per 1,000 mcg/1,000 kcal (I2: 77.7%; p < 0.01); for vitamin C: 0.85 (95% CI: 0.73-0.98) per 50 mg/1,000 kcal (I2: 66.1%; p < 0.01); and, for vitamin E: 0.91 (95% CI: 0.84-0.99) per 5 mg/1,000 kcal (I2: 0.0%; p: 0.45). In contrast, the only prospective study identified provided little indication of an association. Although the current case-control data suggest an inverse relationship of endometrial cancer risk with dietary intakes of beta-carotene, vitamin C, and vitamin E from food sources, additional studies are needed, particularly cohort studies, to confirm an association. [ABSTRACT FROM AUTHOR]