A Comparative Study of Stabilizing Effect and Antioxidant Activity of Different Antioxidants on Levodopa-Loaded Liposomes.

PubMed

García Esteban, Elena; Cózar-Bernal, María José; Rabasco Álvarez, Antonio M; González-Rodríguez, María Luisa

2018-06-11

The aim of this study was to evaluate the stability of levodopa liposomes co-loaded with three different antioxidants (curcumin, ascorbic acid and superoxide dismutase (SOD)). For this purpose, multilamellar liposomes were prepared. Curcumin was added into the lipid bilayer while ascorbic acid and SOD were placed into the aqueous phase. The influence of preparation technique and surface charge were also investigated. Vesicles were characterized and free radical scavenging potential was determined. From stability study, ascorbic acid showed better stabilizing effect. These co-loaded liposomes also exhibited potential radical scavenging activity where ascorbic acid played a key role. From the study of different preparation techniques and charge, we concluded that cationic liposomes made by Thin Layer Evaporation following extrusion offered the best physicochemical and stability properties. A dual mechanism of these liposomes implies the chemical stabilization of levodopa (dose reduction) and the antioxidant effect, with a preventive effect on Parkinson´s disease.

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

PubMed

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

2016-02-15

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

Plasmatic antioxidant capacity due to ascorbate using TEMPO scavenging and electron spin resonance.

PubMed

Piehl, Lidia L; Facorro, Graciela B; Huarte, Mónica G; Desimone, Martín F; Copello, Guillermo J; Díaz, Luis E; de Celis, Emilio Rubín

2005-09-01

Ascorbate is the most effective water-soluble antioxidant and its plasma concentration is usually measured by different methods including colorimetric assays, HPLC or capillary electrophoresis. Plasma antioxidant capacity is determined by indexes such as total reactive antioxidant potential, total antioxidant reactivity, oxygen radical absorbance capacity, etc. We developed an alternative method for the evaluation of the plasma antioxidant status due to ascorbate. TEMPO kinetics scavenging analyzed by ESR spectroscopy was performed on plasma samples in different antioxidant situations. Plasma ascorbate concentrations were determined by capillary electrophoresis. Ascorbyl radical levels were measured by ESR. Plasma reactivity with TEMPO (PR-T) reflected plasma ascorbate levels. Average PR-T for normal plasmas resulted 85+/-27 micromol/l (n=43). PR-T during ascorbic acid intake (1 g/day) increased to an average value of 130+/-20 micromol/l (p<0.001, n=20). PR-T correlated with the plasmatic ascorbate levels determined by capillary electrophoresis (r=0.92), presenting as an advantage the avoiding of the deproteination step. Plasma ascorbyl radical levels increase from 16+/-2 to 24+/-3 nmol/l (p<0.005, n=14) after ascorbate intake. PR-T could be considered as a measure of the plasmatic antioxidant capacity due to the plasma ascorbate levels and could be useful to investigate different antioxidant situations.

Evaluation of plasma antioxidant activity in rats given excess EGCg with reference to endogenous antioxidants concentrations and assay methods.

PubMed

Yokotani, Kaori; Umegaki, Keizo

2017-02-01

The contribution of (-)-epigallocatechin gallate (EGCg) intake to in vivo antioxidant activity is unclear, even with respect to plasma. In this study, we examined how administration of EGCg contributes to plasma antioxidant activity, relative to its concentration, endogenous antioxidants, and assay methods, namely oxygen radical absorbance capacity (ORAC) and ferric reducing/antioxidant power (FRAP). Administration of EGCg (500 mg/kg) to rats increased plasma EGCg (4μmol/L as free form) and ascorbic acid (1.7-fold), as well as ORAC (1.2-fold) and FRAP (3-fold) values. The increase in plasma ascorbic acid following EGCg administration was accompanied by its relocation from the adrenal glands and lymphocytes into plasma, and was related to the increase in FRAP. Plasma deproteinization and assays in plasma model solutions revealed that protein levels significantly contributed to ORAC values, where <3 μmol/L EGCg in the presence of protein exhibited minimal antioxidant activity, as measured by both FRAP and ORAC. As the concentration of plasma ascorbic acid was not influenced by deproteinization, differences in FRAP values with and without deproteinization were estimated to determine the contribution of enhanced ascorbic acid attributable to EGCg administration. These results will help to understand the points that should be considered when evaluating EGCg antioxidant activity in plasma.

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

NASA Astrophysics Data System (ADS)

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

1996-04-01

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

Oxidative stress in the hippocampus during experimental seizures can be ameliorated with the antioxidant ascorbic acid

PubMed Central

Santos, Ítala Mônica Sales; da Rocha Tomé, Adriana; Saldanha, Gláucio Barros; Ferreira, Paulo Michel Pinheiro; Militão, Gardenia Carmem Gadelha

2009-01-01

Ascorbic acid has many nonenzymatic actions and is a powerful water-soluble antioxidant. It protects low density lipoproteins from oxidation and reduces harmful oxidants in the central nervous system. Pilocarpine-induced seizures have been suggested to be mediated by increases in oxidative stress. Current studies have suggested that antioxidant compounds may afford some level of neuroprotection against the neurotoxicity of seizures. The objective of the present study was to evaluate the neuroprotective effects of ascorbic acid (AA) in rats, against the observed oxidative stress during seizures induced by pilocarpine. Wistar rats were treated with 0.9% saline (i.p., control group), ascorbic acid (500 mg/kg, i.p., AA group), pilocarpine (400 mg/kg, i.p., pilocarpine group), and the association of ascorbic acid (500 mg/kg, i.p.) plus pilocarpine (400 mg/kg, i.p.), 30 min before of administration of ascorbic acid (AA plus pilocarpine group). After the treatments all groups were observed for 6 h. The enzyme activities as well as the lipid peroxidation and nitrite concentrations were measured using spectrophotometric methods and the results compared to values obtained from saline and pilocarpine-treated animals. Protective effects of ascorbic acid were also evaluated on the same parameters. In pilocarpine group there was a significant increase in lipid peroxidation and nitrite level. However, no alteration was observed in superoxide dismutase and catalase activities. Antioxidant treatment significantly reduced the lipid peroxidation level and nitrite content as well as increased the superoxide dismutase and catalase activities in hippocampus of adult rats after seizures induced by pilocarpine. Our findings strongly support the hypothesis that oxidative stress in hippocampus occurs during seizures induced by pilocarpine, proving that brain damage induced by the oxidative process plays a crucial role in seizures pathogenic consequences, and also imply that a strong protective effect could be achieved using ascorbic acid. PMID:20716907

Exogenous ascorbic acid improves defence responses of sunflower (Helianthus annuus) exposed to multiple stresses.

PubMed

Kaya, Armagan

2017-09-01

Ascorbic acid is an important antioxidant that plays role both on growth and development and also stress response of the plant. The purpose of this study was to determine the effect of ascorbate on physiological and biochemical changes of sunflower that was exposed to multiple stresses. Chlorophyll and carotenoid contents decreased and glutathione, ascorbate and malondialdehyde contents as well as antioxidant enzyme activities increased for sunflower plant that was exposed to 50 mM NaCl and pendimethalin at different concentrations. These changes were found to be more significant in groups simultaneously exposed to both stress factors. While malondialdehyde content decreased, chlorophyll, carotenoid, ascorbate, glutathione contents and antioxidant enzyme activities increased in plants treated exogenously with ascorbate, compared to the untreated samples. According to the findings of our study; compared to individual stress, the effect of stress is more pronounced in sunflower exposed to multiple stresses, and treatment with exogenous ascorbate reduces the negative effects of stress.

Performance of structured lipids incorporating selected phenolic and ascorbic acids.

PubMed

Gruczynska, Eliza; Przybylski, Roman; Aladedunye, Felix

2015-04-15

Conditions applied during frying require antioxidant which is stable at these conditions and provides protection for frying oil and fried food. Novel structured lipids containing nutraceuticals and antioxidants were formed by enzymatic transesterification, exploring canola oil and naturally occurring antioxidants such as ascorbic and selected phenolic acids as substrates. Lipozyme RM IM lipase from Rhizomucor miehei was used as biocatalyst. Frying performance and oxidative stability of the final transesterification products were evaluated. The novel lipids showed significantly improved frying performance compared to canola oil. Oxidative stability assessment of the structured lipids showed significant improvement in resistance to oxidative deterioration compared to original canola oil. Interestingly, the presence of ascorbic acid in an acylglycerol structure protected α-tocopherol against thermal degradation, which was not observed for the phenolic acids. Developed structured lipids containing nutraceuticals and antioxidants may directly affect nutritional properties of lipids also offering nutraceutical ingredients for food formulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

NASA Astrophysics Data System (ADS)

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

2004-09-01

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

Effect of antioxidants on post thaw microscopic, oxidative stress parameter and fertility of Boer goat spermatozoa in Tris egg yolk glycerol extender.

PubMed

Memon, Akeel Ahmed; Wahid, H; Rosnina, Y; Goh, Y M; Ebrahimi, M; Nadia, F M

2012-12-01

This study was conducted to determine the effect of antioxidants on standard semen parameters, lipid peroxidation and fertility of Boer goat semen after cryopreservation. Ejaculates from four bucks were collected, evaluated and pooled at 37°C. The pooled semen was diluted with Tris citric acid fructose for washing. Semen samples, which were diluted with a Tris-based extender containing the antioxidant ascorbic acid (8.5mg/ml), butylated hydroxytoluene (2mM), cysteine (5mM) and hypotaurine (10mM) and an extender without antioxidant supplementation were cooled to 4°C and frozen in 0.25 straws with programmable freezer and finally stored in liquid nitrogen. Data (10 replicates) were analyzed by one-way analysis of variance. Mean (±SEM) progressive motility was significantly higher in ascorbic acid than other supplement groups and control samples (P>0.05). Best values were observed in ascorbic acid followed by BHT, cysteine, and hypotaurine. Antioxidant supplementation in extender showed significant (P<0.05) better values than the control group for sperm membrane integrity, acrosome integrity and viability. The ability of antioxidants to reduce the lipid peroxidation (LPO) after freeze thawing was measured by the formation of malondialdehyde (MDA) using the thiobarbituric acid method. Results showed that addition of antioxidants significantly reduced the rate of LPO in comparison to control (P<0.05). Ascorbic acid exhibited better values (1.27±0.28), than butylated hydroxytoluene, cysteine and hypotaurine 1.32±0.42, 2.27±0.16 and 2.38±0.17 respectively, which are significantly better than control (3.52±0.54). Higher pregnancy rate was observed with ascorbic acid followed by butylated hydroxtolune, hypotaurine and cysteine. However, differences in the fertility rate were non-significant with hypotaurine, cysteine and control groups. Copyright © 2012 Elsevier B.V. All rights reserved.

Antioxidant capacity of different fractions of vegetables and correlation with the contents of ascorbic acid, phenolics, and flavonoids.

PubMed

Ji, Linlin; Wu, Jianquan; Gao, Weina; Wei, Jingyu; Yang, Jijun; Guo, Changjiang

2011-01-01

The antioxidant capacity of different fractions of 17 vegetables were analyzed using ferric reducing antioxidant power assay (FRAP assay) after water and acetone extractions. The contents of ascorbic acid, phenolics, and flavonoids were determined and their correlations with FRAP value were investigated. The results showed that the peel or leaf fractions of vegetables were stronger than the pulp or stem fractions in antioxidant capacity based on total FRAP value. Lotus root peel was the highest and cucumber pulp the lowest in total FRAP value among the vegetable fractions analyzed. All water extracts were higher in FRAP value than the acetone extracts. The FRAP value was significantly correlated with the contents of ascorbic acid, phenolics, or flavonoids in water extracts, in which the phenolics contributed most based on multivariate regression analysis. We conclude that different vegetable fractions were remarkably different in antioxidant capacity. The phenolics are responsible mostly for the antioxidant capacity of vegetables in vitro. © 2011 Institute of Food Technologists®

Peroxidase-like activity of the Co3O4 nanoparticles used for biodetection and evaluation of antioxidant behavior

NASA Astrophysics Data System (ADS)

Jia, Huimin; Yang, Dongfang; Han, Xiangna; Cai, Junhui; Liu, Haiying; He, Weiwei

2016-03-01

Nanostructured enzyme mimics are of great interest as promising alternatives to artificial enzymes for biomedical and catalytic applications. Studying the chemical interactions between antioxidants and nano-enzymes may result in a better understanding of the antioxidant capability of antioxidants and may help improve the function of artificial enzymes to better mimic natural enzymes. In this study, using Co3O4 nanoparticles (NPs) as peroxidase mimics to catalyze the oxidation of chromophoric substrates by H2O2, we developed a platform that acts as a biosensor for hydrogen peroxide and glucose and that can study the inhibitory effects of natural antioxidants on peroxidase mimics. This method can be applied specifically to glucose detection in real samples. Three natural antioxidants, gallic acid (GA), tannic acid (TA), and ascorbic acid (AA), were compared for their antioxidant capabilities. We found that these three antioxidants efficiently inhibit peroxidase-like activity with concentration dependence. The antioxidants showed different efficiencies, in the following order: tannic acid > gallic acid > ascorbic acid. They also showed distinct modes of inhibition based on different interaction mechanisms. This study serves as a proof-of-concept that nano-enzyme mimics can be used to evaluate antioxidant capabilities and to screen enzyme inhibitors.Nanostructured enzyme mimics are of great interest as promising alternatives to artificial enzymes for biomedical and catalytic applications. Studying the chemical interactions between antioxidants and nano-enzymes may result in a better understanding of the antioxidant capability of antioxidants and may help improve the function of artificial enzymes to better mimic natural enzymes. In this study, using Co3O4 nanoparticles (NPs) as peroxidase mimics to catalyze the oxidation of chromophoric substrates by H2O2, we developed a platform that acts as a biosensor for hydrogen peroxide and glucose and that can study the inhibitory effects of natural antioxidants on peroxidase mimics. This method can be applied specifically to glucose detection in real samples. Three natural antioxidants, gallic acid (GA), tannic acid (TA), and ascorbic acid (AA), were compared for their antioxidant capabilities. We found that these three antioxidants efficiently inhibit peroxidase-like activity with concentration dependence. The antioxidants showed different efficiencies, in the following order: tannic acid > gallic acid > ascorbic acid. They also showed distinct modes of inhibition based on different interaction mechanisms. This study serves as a proof-of-concept that nano-enzyme mimics can be used to evaluate antioxidant capabilities and to screen enzyme inhibitors. Electronic supplementary information (ESI) available: Fig. S1-S6. See DOI: 10.1039/c6nr00860g

Effect of ascorbic acid on prevention of hypercholesterolemia induced atherosclerosis.

PubMed

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

2006-04-01

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

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

PubMed

Elikov, A V; Tsapok, P I

2010-01-01

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

Antioxidant capacity of human blood plasma and human urine: simultaneous evaluation of the ORAC index and ascorbic acid concentration employing pyrogallol red as probe.

PubMed

Torres, P; Galleguillos, P; Lissi, E; López-Alarcón, C

2008-10-15

The oxygen radical absorbance capacity (ORAC) methodology has been employed to estimate the antioxidant capacity of human blood plasma and human urine using pyrogallol red (ORAC-PGR) as target molecule. Uric acid, reduced glutathione, human serum albumin, and ascorbic acid (ASC) inhibited the consumption of pyrogallol red, but only ASC generated an induction time. Human blood plasma and human urine protected efficiently pyrogallol red. In these assays, both biological fluids generated neat induction times that were removed by ascorbate oxidase. From these results, ORAC-PGR method could be proposed as a simple alternative to evaluate an ORAC index and, simultaneously, to estimate the concentration of ascorbic acid in human blood plasma or human urine.

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

PubMed

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

2012-11-01

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

Evaluation of synergistic antioxidant potential of complex mixtures using oxygen radical absorbance capacity (ORAC) and electron paramagnetic resonance (EPR).

PubMed

Parker, Tory L; Miller, Samantha A; Myers, Lauren E; Miguez, Fernando E; Engeseth, Nicki J

2010-01-13

Previous research has demonstrated that certain combinations of compounds result in a decrease in toxic or pro-oxidative effects, previously noted when compounds were administered singly. Thus, there is a need to study many complex interactions further. Two in vitro techniques [electron paramagnetic resonance (EPR) and oxygen radical absorbance capacity (ORAC) assays] were used in this study to assess pro- and antioxidant capacity and synergistic potential of various compounds. Rutin, p-coumaric acid, abscisic acid, ascorbic acid, and a sugar solution were evaluated individually at various concentrations and in all 26 possible combinations at concentrations found in certain foods (honey or papaya), both before and after simulated digestion. EPR results indicated sugar-containing combinations provided significantly higher antioxidant capacity; those combinations containing sugars and ascorbic acid demonstrated synergistic potential. The ORAC assay suggested additive effects, with some combinations having synergistic potential, although fewer combinations were significantly synergistic after digestion. Finally, ascorbic acid, caffeic acid, quercetin, and urate were evaluated at serum-achievable levels. EPR analysis did not demonstrate additive or synergistic potential, although ORAC analysis did, principally in combinations containing ascorbic acid.

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

NASA Astrophysics Data System (ADS)

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

2010-12-01

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

Physiology response of fourth generation saline resistant soybean (Glycine max (L.) Merrill) with application of several types of antioxidants

NASA Astrophysics Data System (ADS)

Manurung, I. R.; Rosmayati; Rahmawati, N.

2018-02-01

Antioxidant applications are expected to reduce the adverse effects of soil saline. This research was conducted in plastic house, Plant Tissue Laboratory Faculty of Agriculture and Plant Physiology Laboratory Faculty of Mathematic and Natural Science, Universitas Sumatera Utara, Medan also in Research Centers and Industry Standardization, Medan from July-December 2016. The objective of the research was to know the effect of various antioxidant treatments with different concentrations (control, ascorbic acid 250, 500 and 750 ppm; salicylic acid 250, 500 and 750 ppm; α-tocopherol 250, 500 and 750 ppm) on fourth generation soybean physiology in saline condition (Electric Conductivity 5-6 dS/m). The results of this research showed that the antioxidant type and concentration affected not significantly to physiology of fourth generation soybean. Descriptively the highest average of superoxide dismutase and peroxide dismutase was showed on ascorbic acid 250 ppm. The highest average of ascorbate peroxidase was showed on α-tocopherol 750 ppm. The highest average of carotenoid content was showed on ascorbic acid 500 ppm. The highest average of chlorophyll content was showed on α-tocopherol 250 ppm. The highest average of ratio of K/Na was showed on salicylic acid 250 ppm.

Enzymatic extraction of star gooseberry (Phyllanthus acidus) juice with high antioxidant level

NASA Astrophysics Data System (ADS)

Loan, Do Thi Thanh; Tra, Tran Thi Thu; Nguyet, Ton Nu Minh; Man, Le Van Viet

2017-09-01

Ascorbic acid and phenolic compounds are main antioxidants in star gooseberry (Phyllanthus acidus) fruit. In this study, Pectinex Ultra SP-L preparation with pectinase activity was used in the extraction of star gooseberry juice. The effects of pectinase concentration and biocatalytic time on the content of ascorbic acid, phenolic compounds and antioxidant activity of the fruit juice were firstly investigated. Response surface methodology was then used to optimize the conditions of enzymatic extraction for maximizing the antioxidant activity of the star gooseberry juice. The optimal pectinase concentration and biocatalytic time were 19 polygalacturonase units per 100g pulp dry weight and 67 min, respectively under which the maximal antioxidant activity achieved 5595±6 µmol Trolox equivalent per 100g juice dry weight. On the basis of kinetic model of second-order extraction, the extraction rate constant of ascorbic acid and phenolic compounds in the enzymatic extraction increased approximately 21% and 157%, respectively in comparison with that in the conventional extraction. Application of pectinase preparation to the fruit juice extraction was therefore potential for improvement in antioxidant level of the product.

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

PubMed

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

2002-02-01

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

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

PubMed Central

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

2012-01-01

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

Impact of optimised cooking on the antioxidant activity in edible mushrooms.

PubMed

Ng, Zhi Xiang; Tan, Wan Chein

2017-11-01

This study aimed to investigate the effect of four cooking methods with different durations on the in vitro antioxidant activities of five edible mushrooms, namely Agaricus bisporus , Flammulina velutipes , Lentinula edodes , Pleurotus ostreatus and Pleurotus eryngii. Among the raw samples, A. bisporus showed the highest total antioxidant activity (reducing power and radical scavenging), total flavonoid, ascorbic acid and water soluble phenolic contents. Short-duration steam cooking (3 min) increased the total flavonoid and ascorbic acid while prolonged pressure cooking (15 min) reduced the water soluble phenolic content in the mushrooms. The retention of antioxidant value in the mushrooms varied with the variety of mushroom after the cooking process. The cooking duration significantly affected the ascorbic acid in the mushrooms regardless of cooking method. To achieve the best antioxidant values, steam cooking was preferred for F. velutipes (1.5 min), P. ostreatus (4.5 min) and L. edodes (4.5 min) while microwave cooking for 1.5 min was a better choice for A. bisporus . Pressure cooked P. eryngii showed the best overall antioxidant value among the cooked samples. Optimised cooking method including pressure cooking could increase the antioxidant values in the edible mushrooms.

Effect of three cooking methods on nutrient components and antioxidant capacities of bamboo shoot (Phyllostachys praecox C.D. Chu et C.S. Chao)*

PubMed Central

Zhang, Jin-jie; Ji, Rong; Hu, Ya-qin; Chen, Jian-chu; Ye, Xing-qian

2011-01-01

Three cooking methods, namely boiling, steaming, and stir-frying for 5 to 10 min, were used to evaluate the effect on nutrient components, free amino acids, L-ascorbic acid, total phenolic contents, and antioxidant capacities of bamboo shoots (Phyllostachys praecox). Results showed that boiling and stir-frying had a great effect on the nutrient components and they decreased the contents of protein, soluble sugar, and ash, and caused a great loss in the total free amino acids (decreased by 38.35% and 34.86%, respectively). Significant differences (P<0.05) in free amino acids were observed in the samples cooked by different methods. Stir-fried bamboo shoots had a high fat content which increased by 528.57% because of the addition of edible oil. After boiling, the L-ascorbic acid and total phenolic contents were significantly reduced, while steaming increased total phenolic content by 3.98% and stir-frying well-preserved L-ascorbic acid (78.87% of its previous content). Results of the antioxidative property study showed that stir-frying could increase antioxidant capacities of bamboo shoots. It is concluded that stir-frying is more suitable for bamboo shoots because it could obtain the maximum retention of antioxidant capacities. PMID:21887851

Effect of three cooking methods on nutrient components and antioxidant capacities of bamboo shoot (Phyllostachys praecox C.D. Chu et C.S. Chao).

PubMed

Zhang, Jin-jie; Ji, Rong; Hu, Ya-qin; Chen, Jian-chu; Ye, Xing-qian

2011-09-01

Three cooking methods, namely boiling, steaming, and stir-frying for 5 to 10 min, were used to evaluate the effect on nutrient components, free amino acids, L-ascorbic acid, total phenolic contents, and antioxidant capacities of bamboo shoots (Phyllostachys praecox). Results showed that boiling and stir-frying had a great effect on the nutrient components and they decreased the contents of protein, soluble sugar, and ash, and caused a great loss in the total free amino acids (decreased by 38.35% and 34.86%, respectively). Significant differences (P<0.05) in free amino acids were observed in the samples cooked by different methods. Stir-fried bamboo shoots had a high fat content which increased by 528.57% because of the addition of edible oil. After boiling, the L-ascorbic acid and total phenolic contents were significantly reduced, while steaming increased total phenolic content by 3.98% and stir-frying well-preserved L-ascorbic acid (78.87% of its previous content). Results of the antioxidative property study showed that stir-frying could increase antioxidant capacities of bamboo shoots. It is concluded that stir-frying is more suitable for bamboo shoots because it could obtain the maximum retention of antioxidant capacities.

Genotoxic effect of ethacrynic acid and impact of antioxidants

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

Ward, William M.; Hoffman, Jared D.; Loo, George, E-mail: g_loo@uncg.edu

It is known that ethacrynic acid (EA) decreases the intracellular levels of glutathione. Whether the anticipated oxidative stress affects the structural integrity of DNA is unknown. Therefore, DNA damage was assessed in EA-treated HCT116 cells, and the impact of several antioxidants was also determined. EA caused both concentration-dependent and time-dependent DNA damage that eventually resulted in cell death. Unexpectedly, the DNA damage caused by EA was intensified by either ascorbic acid or trolox. In contrast, EA-induced DNA damage was reduced by N-acetylcysteine and by the iron chelator, deferoxamine. In elucidating the DNA damage, it was determined that EA increased themore » production of reactive oxygen species, which was inhibited by N-acetylcysteine and deferoxamine but not by ascorbic acid and trolox. Also, EA decreased glutathione levels, which were inhibited by N-acetylcysteine. But, ascorbic acid, trolox, and deferoxamine neither inhibited nor enhanced the capacity of EA to decrease glutathione. Interestingly, the glutathione synthesis inhibitor, buthionine sulfoxime, lowered glutathione to a similar degree as EA, but no noticeable DNA damage was found. Nevertheless, buthionine sulfoxime potentiated the glutathione-lowering effect of EA and intensified the DNA damage caused by EA. Additionally, in examining redox-sensitive stress gene expression, it was found that EA increased HO-1, GADD153, and p21mRNA expression, in association with increased nuclear localization of Nrf-2 and p53 proteins. In contrast to ascorbic acid, trolox, and deferoxamine, N-acetylcysteine suppressed the EA-induced upregulation of GADD153, although not of HO-1. Overall, it is concluded that EA has genotoxic properties that can be amplified by certain antioxidants. - Highlights: • Ethacrynic acid (EA) caused cellular DNA damage. • EA-induced DNA damage was potentiated by ascorbic acid or trolox. • EA increased ROS production, not inhibited by ascorbic acid or trolox. • EA decreased glutathione levels, not prevented by ascorbic acid or trolox. • Buthionine sulfoxime intensified the DNA damage caused by EA.« less

Flavone Biotransformation by Aspergillus niger and the Characterization of Two Newly Formed Metabolites

PubMed Central

Assawah, Suzan W.; El-Sharkawy, Saleh H.; Abdel-Salam, Amal

2008-01-01

Aspergillus niger isolated from Allium sativum was used at large scale fermentation (150 mg flavone/200 ml medium) to obtain suitable amounts of the products, efficient for identification. Then spectral analysis (UV, IR, 1H-NMR, 13C-NMR) and mass spectrometry were performed for the two products, which contributed to the identification process. The metabolite (1) was identified as 2'-hydroxydihydrochalcone, and the metabolite (2) was identified as 2'-hydroxyphenylmethylketone, which were more active than flavone itself. Antioxidant activities of the two isolated metabolites were tested compared with ascorbic acid. Antioxidant activity of metabolite (1) was recorded 64.58% which represented 79% of the antioxidant activity of ascorbic acid, and metabolite (2) was recorded 54.16% (67% of ascorbic acid activity). However, the antioxidant activity of flavone was recorded 37.50% which represented 46% of ascorbic acid activity. The transformed products of flavone have antimicrobial activity against Pseudomonas aeruginosa, Aspergillus flavus and Candida albicans, with MIC was recorded 250 µg/ml for metabolite (2) against all three organism and 500, 300, and 300 µg/ml for metabolite (1) against tested microorganisms (P. aeruginosa, Escherichia coli, Bacillus subtilis, and Klebsiella pneumonia, Fusarium moniliforme, A. flavus, Saccharomyces cerviceae, Kluveromyces lactis and C. albicans) at this order. PMID:23990746

Vitamin C transport and its role in the central nervous system

PubMed Central

May, James M.

2013-01-01

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

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

PubMed

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

2015-01-01

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

Evaluation of anti-apoptotic activity of different dietary antioxidants in renal cell carcinoma against hydrogen peroxide

PubMed Central

Garg, Neeraj K; Mangal, Sharad; Sahu, Tejram; Mehta, Abhinav; Vyas, Suresh P; Tyagi, Rajeev K

2011-01-01

Objective To evaluate the anti-apoptotic and radical scavenging activities of dietary phenolics, namely ascorbic acid,α-tocopherol acetate, citric acid, salicylic acid, and estimate H2O2-induced apoptosis in renal cell carcinoma cells. Methods The intracellular antioxidant potency of antioxidants was investigated. H2O2-induced apoptosis in RCC-26 was assayed with the following parameters: cell viability (% apoptosis), nucleosomal damage and DNA fragmentation, bcl-2 levels and flow cytometery analysis (ROS production evaluation). Results The anticancer properties of antioxidants such as ascorbic acid, α-tocopherol acetate, citric acid, salicylic acid with perdurable responses were investigated. It was observed that these antioxidants had protective effect (anti-apoptotic activity) against hydrogen peroxide (H2O2) in renal cell carcinoma (RCC-26) cell line. Conclusions This study reveals and proves the anticancer properties. However, in cancer cell lines anti-apoptotic activity can indirectly reflect the cancer promoter activity through radicals scavenging, and significantly protect nucleus and bcl-2. PMID:23569726

Antioxidant effectiveness of organically and non-organically grown red oranges in cell culture systems.

PubMed

Tarozzi, A; Hrelia, S; Angeloni, C; Morroni, F; Biagi, P; Guardigli, M; Cantelli-Forti, G; Hrelia, P

2006-03-01

Consumers consider plant food products from organic origin healthier than the corresponding conventional plant foods. Clear experimental evidence supporting this assumption is still lacking. To determine if the organic red oranges have a higher phyto-chemical content (i. e., phenolics, anthocyanins and ascorbic acid), total antioxidant activity and in vitro bioactivity, in terms of protective effect against oxidative damage at cellular level, than nonorganic red oranges. Total phenolics were measured using the Folin Ciocalteau assay, while total anthocyanins and ascorbic acid levels were determined by spectrophotometric and HPLC analysis, respectively. In addition, the total antioxidant activity of red orange extracts was measured by the ABTS(*+) test. The ability of red orange extracts to counteract conjugated diene containing lipids and free radical production in cultured rat cardiomyocytes and differentiated Caco-2 cells, respectively, was assessed. Organic oranges had significantly higher total phenolics, total anthocyanins and ascorbic acid levels than the corresponding non-organic oranges (all p < 0.05). Moreover, the organic orange extracts had a higher total antioxidant activity than non-organic orange extracts (p < 0.05). In addition, our results indicate that red oranges have a strong capacity of inhibiting the production of conjugated diene containing lipids and free radicals in rat cardiomyocytes and differentiated Caco-2 cells, respectively. Statistically higher levels of antioxidant activity in both cell models were found in organically grown oranges as compared to those produced by integrated agriculture practice. Our results clearly show that organic red oranges have a higher phytochemical content (i. e., phenolics, anthocyanins and ascorbic acid), total antioxidant activity and bioactivity than integrated red oranges. Further studies are needed to confirm whether the organic agriculture practice is likely to increase the antioxidant activity of other varieties of fruits and vegetables.

Polyphenol oxidase activity and antioxidant properties of Yomra apple (Malus communis L.) from Turkey.

PubMed

Can, Zehra; Dincer, Barbaros; Sahin, Huseyin; Baltas, Nimet; Yildiz, Oktay; Kolayli, Sevgi

2014-12-01

In this study, firstly, antioxidant and polyphenol oxidase (PPO) properties of Yomra apple were investigated. Seventeen phenolic constituents were measured by reverse phase-high-performance liquid chromatography (RP-HPLC). Total phenolic compounds (TPCs), ferric reducing antioxidant power (FRAP) and 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging activities were performed to measure antioxidant capacity. Some kinetic parameters (Km, Vmax), and inhibition behaviors against five different substrates were measured in the crude extract. Catechin and chlorogenic acid were found as the major components in the methanolic extract, while ferulic acid, caffeic acid, p-hydroxybenzoic acid, quercetin and p-coumaric acid were small quantities. Km values ranged from 0.70 to 10.10 mM in the substrates, and also 3-(4-hydroxyphenyl) propanoic acid (HPPA) and L-DOPA showed the highest affinity. The inhibition constant of Ki were ranged from 0.05 to 14.90 mM against sodium metabisulphite, ascorbic acid, sodium azide and benzoic acid, while ascorbic acid and sodium metabisulphite were the best inhibitors.

In vitro free radical scavenging activity of ethanolic extract of the whole plant of Evolvulus alsinoides (L.) L.

PubMed

Gomathi, Duraisamy; Ravikumar, Ganesan; Kalaiselvi, Manokaran; Vidya, Balasubramaniam; Uma, Chandrasekar

2015-06-01

To identify the free radical scavenging activity of ethanolic extract of Evolvulus alsinoides. The free radical scavenging activity was evaluated by in vitro methods like reducing power assay, total antioxidant activity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) reduction, superoxide radical scavenging activity, 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(+)) scavenging activity, hydroxyl radical scavenging assay, and nitric oxide radical scavenging assay, which were studied by using ascorbic acid as standard. The extract showed significant activities in all antioxidant assays compared with the reference antioxidant ascorbic acid. The total antioxidant activity as well as the reducing power was also found to increase in a dose-dependent manner. Evolvulus alsinoides may act as a chemopreventive agent, providing antioxidant properties and offering effective protection from free radicals.

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

PubMed

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

2012-11-01

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

Antioxidant effects of aminosalicylates and potential new drugs for inflammatory bowel disease: assessment in cell-free systems and inflamed human colorectal biopsies.

PubMed

Simmonds, N J; Millar, A D; Blake, D R; Rampton, D S

1999-03-01

The therapeutic efficacy of 5-aminosalicylic acid in inflammatory bowel disease may be related to its antioxidant properties. To compare in vitro the antioxidant effects of conventional drugs (5-aminosalicylic acid, corticosteroids, metronidazole), with new aminosalicylates (4-aminosalicylic acid, balsalazide) and other potential therapies (ascorbate, N-acetylcysteine, glutathione, verapamil). Compounds were assessed for efficacy in reducing the in vitro production of reactive oxygen species by cell-free systems (using xanthine/xanthine oxidase, with or without myeloperoxidase) and by colorectal biopsies from patients with ulcerative colitis using luminol-amplified chemiluminescence. 5-aminosalicylic acid and balsalazide were more potent antioxidants than 4-aminosalicylic acid or N-acetyl-5-aminosalicylic acid in cell-free systems. 5-aminosalicylic acid (20 mM) and balsalazide (20 mM) inhibited rectal biopsy chemiluminescence by 93% and 100%, respectively, compared with only 59% inhibition by 4-aminosalicylic acid (20 mM). Hydrocortisone, metronidazole and verapamil had no significant effect on chemiluminescence in any system. Ascorbate (20 mM) inhibited chemiluminescence by 100% in cell-free systems and by 60% in rectal biopsies. N-acetyl cysteine (10 mM), and both oxidized and reduced glutathione (10 mM), completely inhibited chemiluminescence in cell-free systems, but not with rectal biopsies. The antioxidant effects of compounds varies between cell-free systems and inflamed colorectal biopsies. The effect of drugs on the chemiluminescence produced by these two assay systems is useful for screening potentially new antioxidant treatments for inflammatory bowel disease. Ascorbate seems worth further study as a novel therapy.

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

PubMed

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

2003-04-01

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

ASCORBIC ACID IS DECREASED IN INDUCED SPUTUM OF MILD ASTHMATICS

EPA Science Inventory

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

Inhibition of free radical-induced erythrocyte hemolysis by 2-O-substituted ascorbic acid derivatives.

PubMed

Takebayashi, Jun; Kaji, Hiroaki; Ichiyama, Kenji; Makino, Kazutaka; Gohda, Eiichi; Yamamoto, Itaru; Tai, Akihiro

2007-10-15

Inhibitory effects of 2-O-substituted ascorbic acid derivatives, ascorbic acid 2-glucoside (AA-2G), ascorbic acid 2-phosphate (AA-2P), and ascorbic acid 2-sulfate (AA-2S), on 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative hemolysis of sheep erythrocytes were studied and were compared with those of ascorbic acid (AA) and other antioxidants. The order of the inhibition efficiency was AA-2S> or =Trolox=uric acid> or =AA-2P> or =AA-2G=AA>glutathione. Although the reactivity of the AA derivatives against AAPH-derived peroxyl radical (ROO(*)) was much lower than that of AA, the derivatives exerted equal or more potent protective effects on AAPH-induced hemolysis and membrane protein oxidation. In addition, the AA derivatives were found to react per se with ROO(*), not via AA as an intermediate. These findings suggest that secondary reactions between the AA derivative radical and ROO(*) play a part in hemolysis inhibition. Delayed addition of the AA derivatives after AAPH-induced oxidation of erythrocytes had already proceeded showed weaker inhibition of hemolysis compared to that of AA. These results suggest that the AA derivatives per se act as biologically effective antioxidants under moderate oxidative stress and that AA-2G and AA-2P may be able to act under severe oxidative stress after enzymatic conversion to AA in vivo.

Antioxidant Activities of Hot Water Extracts from Various Spices

PubMed Central

Kim, Il-Suk; Yang, Mi-Ra; Lee, Ok-Hwan; Kang, Suk-Nam

2011-01-01

Recently, the natural spices and herbs such as rosemary, oregano, and caraway have been used for the processing of meat products. This study investigates the antioxidant activity of 13 spices commonly used in meat processing plants. The hot water extracts were then used for evaluation of total phenolic content, total flavonoids content and antioxidant activities. Our results show that the hot water extract of oregano gave the highest extraction yield (41.33%) whereas mace (7.64%) gave the lowest. The DPPH radical scavenging ability of the spice extracts can be ranked against ascorbic acid in the order ascorbic acid > clove > thyme > rosemary > savory > oregano. The values for superoxide anion radical scavenging activities were in the order of marjoram > rosemary > oregano > cumin > savory > basil > thyme > fennel > coriander > ascorbic acid. When compared to ascorbic acid (48.72%), the hydroxyl radical scavenging activities of turmeric and mace were found to be higher (p < 0.001). Clove had the highest total phenolic content (108.28 μg catechin equivalent (CE)/g). The total flavonoid content of the spices varied from 324.08 μg quercetin equivalent (QE)/g for thyme to 3.38 μg QE/g for coriander. Our results indicate that hot water extract of several spices had a high antioxidant activity which is partly due to the phenolic and flavonoid compounds. This provides basic data, having implications for further development of processed food products. PMID:21747728

Effect of Antioxidants and Carbohydrates in Callus Cultures of Taxus brevifolia: Evaluation of Browning, Callus Growth, Total Phenolics and Paclitaxel Production

PubMed Central

Yari Khosroushahi, Ahmad; Naderi-Manesh, Hossein; Toft Simonsen, Henrik

2011-01-01

Introduction To control the tissue browning phenomenon, callus growth, total phenolics and paclitaxel production, in the current investigation, we evaluated the effects of citric acid and ascorbic acid (as antioxidants) and glucose, fructose and sucrose in callus cultures of Taxus brevifolia. Methods To obtain healthy callus/cell lines of Taxus brevifolia, the effects of two antioxidants ascorbic acid (100-1000 mg/L) and citric acid (50-500 mg/L), and three carbohydrates (glucose, fructose and sucrose (5-10 g/L)) were studied evaluating activities of polyphenol oxidase (PPO) and peroxidase (PO) enzymes, callus growth/browning, total phenolics and paclitaxel production. Results These antioxidants (ascorbic acid and citric acid) failed to show significant effects on callus growth, browning intensity or paclitaxel production. However, the carbohydrates imposed significant effects on the parameters studied. High concentrations of both glucose and sucrose increased the browning intensity, thus decreased callus growth. Glucose increased paclitaxel production, but sucrose decreased it. Conclusion These results revealed that the browning phenomenon can be controlled through supplementation of the growth media with glucose, sucrose (5 g/L) and fructose (10 g/L), while increased paclitaxel production can be obtain by the optimized media supplemented with glucose (10 g/L), sucrose and fructose (5 g/L). PMID:23678406

New evidence for antioxidant properties of vitamin C.

PubMed

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

2000-01-01

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

Effect of Chitosan Coating on the Postharvest Quality and Antioxidant Enzyme System Response of Strawberry Fruit during Cold Storage

PubMed Central

Petriccione, Milena; Mastrobuoni, Francesco; Pasquariello, Maria Silvia; Zampella, Luigi; Nobis, Elvira; Capriolo, Giuseppe; Scortichini, Marco

2015-01-01

The effectiveness of chitosan fruit coating to delay the qualitative and nutraceutical traits of three strawberry cultivars, namely “Candonga”, “Jonica” and “Sabrina”, as well as the effects of chitosan on antioxidant enzymes were evaluated. The fruits were coated with 1% and 2% chitosan solution and stored at 2 °C for nine days. Samples were taken every three days. Physico-chemical (weight loss, soluble solid content and titratable acidity) and nutraceutical (total polyphenol, anthocyanin, flavonoid, ascorbic acid content and antioxidant capacity) properties along with the enzymatic activity (catalase (CAT), ascorbate peroxidase (APX), polyphenol oxidase (PPO), guaiacol peroxidase (GPX) and lipoxygenase (LOX)) were evaluated. Chitosan treatment significantly reduced water loss and delayed the qualitative changes in color, titratable acidity and ascorbic acid content in dose- and cultivar-dependent manners. Additionally, changes in the total polyphenol, anthocyanin and flavonoid contents and the antioxidant capacity of chitosan-coated strawberry fruits were delayed. Chitosan coating enhanced the activity of some antioxidant enzymes, preventing flesh browning and reducing membrane damage. A global view of the responses of the three strawberry cultivars to chitosan coating and storage temperature was obtained using principal component analysis. Chitosan-coated fruit exhibited a slower rate of deterioration, compared to uncoated fruit in all tested cultivars. PMID:28231220

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

PubMed Central

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

2015-01-01

Ascorbic acid is an effective antioxidant and free radical scavenger. Therefore, it is expected that ascorbic acid should act as a radioprotectant. We investigated the effects of post-radiation treatment with ascorbic acid on mouse survival. Mice received whole body irradiation (WBI) followed by intraperitoneal administration of ascorbic acid. Administration of 3 g/kg of ascorbic acid immediately after exposure significantly increased mouse survival after WBI at 7 to 8 Gy. However, administration of less than 3 g/kg of ascorbic acid was ineffective, and 4 or more g/kg was harmful to the mice. Post-exposure treatment with 3 g/kg of ascorbic acid reduced radiation-induced apoptosis in bone marrow cells and restored hematopoietic function. Treatment with ascorbic acid (3 g/kg) up to 24 h (1, 6, 12, or 24 h) after WBI at 7.5 Gy effectively improved mouse survival; however, treatments beyond 36 h were ineffective. Two treatments with ascorbic acid (1.5 g/kg × 2, immediately and 24 h after radiation, 3 g/kg in total) also improved mouse survival after WBI at 7.5 Gy, accompanied with suppression of radiation-induced free radical metabolites. In conclusion, administration of high-dose ascorbic acid might reduce radiation lethality in mice even after exposure. PMID:25651298

Chemical repair of base lesions, AP-sites, and strand breaks on plasmid DNA in dilute aqueous solution by ascorbic acid

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

Hata, Kuniki; Advanced Science Research Center, Japan Atomic Energy Agency, 2-4 Shirakatashirane, Tokai-mura, Naka-gun, Ibaraki 319-1195; Urushibara, Ayumi

Highlights: •We report a novel mechanism of radiation protection of DNA by chemical activity of ascorbic acid. •The “chemical repair” of DNA damage was revealed using biochemical assay and chemical kinetics analysis. •We found that ascorbic acid significantly repairs precursors of nucleobase lesions and abasic sites. •However, ascorbic acid seldom repairs precursors of DNA-strand breaks. -- Abstract: We quantified the damage yields produced in plasmid DNA by γ-irradiation in the presence of low concentrations (10–100 μM) of ascorbic acid, which is a major antioxidant in living systems, to clarify whether it chemically repairs radiation damage in DNA. The yield ofmore » DNA single strand breaks induced by irradiation was analyzed with agarose gel electrophoresis as conformational changes in closed circular plasmids. Base lesions and abasic sites were also observed as additional conformational changes by treating irradiated samples with glycosylase proteins. By comparing the suppression efficiencies to the induction of each DNA lesion, in addition to scavenging of the OH radicals derived from water radiolysis, it was found that ascorbic acid promotes the chemical repair of precursors of AP-sites and base lesions more effectively than those of single strand breaks. We estimated the efficiency of the chemical repair of each lesion using a kinetic model. Approximately 50–60% of base lesions and AP-sites were repaired by 10 μM ascorbic acid, although strand breaks were largely unrepaired by ascorbic acid at low concentrations. The methods in this study will provide a route to understanding the mechanistic aspects of antioxidant activity in living systems.« less

Antioxidants, low molecular weight carbohydrates, and total antioxidant capacity in strawberries (Fragaria x ananassa): effects of cultivar, ripening, and storage.

PubMed

Olsson, Marie E; Ekvall, Jimmy; Gustavsson, Karl-Erik; Nilsson, Jessica; Pillai, Deepa; Sjöholm, Ingegerd; Svensson, Ulla; Akesson, Björn; Nyman, Margareta G L

2004-05-05

Four cultivars of strawberries (Senga Sengana, BFr77111, Elsanta, and Honeoye) were studied for their content of antioxidants, total antioxidant capacity, and low molecular weight carbohydrates in relation to harvest year, ripening stage, and cold storage. For ascorbic acid, chlorogenic acid, ellagic acid, and total antioxidative capacity, measured in both water-soluble and water-insoluble extracts, there was a 2-5-fold variation among cultivars. Unripe berries contained lower concentrations of chlorogenic acid and p-coumaric acid and also quercetin and kaempferol compared with riper berries. During cold storage for up to 3 days, relatively few changes in the concentration of the different antioxidants occurred. The concentrations of several investigated parameters were interrelated, for example, for ascorbic acid and water-soluble antioxidant capacity and for ellagic acid and water-insoluble antioxidant capacity. The dominating sugars in strawberries were fructose and glucose, but considerable amounts of sucrose were also present, and their contents varied among cultivars, giving a predicted glycemic index of approximately 81. Verbascose, raffinose, and stachyose were found in only minor amounts. The study shows that the concentration of a number of bioactive compounds in strawberries varied according to cultivar, ripening stage, and storage. This information should make it possible to select strawberries with an optimal content of bioactive compounds.

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

PubMed

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

2017-05-01

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

Evaluation of antioxidant and mutagenic activities of honey-sweetened cashew apple nectar.

PubMed

da Silva, Robson Alves; Dihl, Rafael Rodrigues; Nascimento e Santos, Débora; de Abreu, Bianca Regina Ribas; de Lima, Alessandro; de Andrade, Heloisa Helena Rodrigues; Lehmann, Mauricio

2013-12-01

In vitro chemical properties and antioxidant potential and in vivo mutagenic activity of honey-sweetened cashew apple nectar (HSCAN), a beverage produced from the cashew pseudo-fruit (Anacardium occidentale L.) and of its constituents were assessed. Analytical procedures were carried out to investigate the honey used in the HSCAN preparation, and the results observed are in accordance with Brazilian legal regulations, except for diastase number. HSCAN and pulp were investigated for ascorbic acid, carotenoid, anthocyanin and total phenolic contents, and both showed high acid ascorbic concentrations. Antioxidant capacity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and/or β-carotene/linoleic acid systems were applied and demonstrated a weak antioxidant capacity of honey and HSCAN, but cashew apple pulp demonstrated high antioxidant capacity. A weakly positive mutagenic effect of cashew pulp 20% was observed using the somatic mutation and recombination test (SMART) in Drosophila melanogaster only in the high-bioactivation (HB) cross. On the contrary, HSCAN was not mutagenic in both standard and high bioactivation crosses. HSCAN exhibited slight antioxidant activity, which could be associated with the high amount of ascorbic acid found in the samples evaluated. The beverage prepared did not induce DNA damage in somatic cells of D. melanogaster, which means that it is neither mutagenic nor recombinagenic in this test system. Copyright © 2013 Elsevier Ltd. All rights reserved.

Lipid oxidation in base algae oil and water-in-algae oil emulsion: Impact of natural antioxidants and emulsifiers.

PubMed

Chen, Bingcan; Rao, Jiajia; Ding, Yangping; McClements, David Julian; Decker, Eric Andrew

2016-07-01

The impact of natural hydrophilic antioxidants, metal chelators, and hydrophilic antioxidant/metal chelator mixture on the oxidative stability of base algae oil and water-in-algae oil emulsion was investigated. The results showed that green tea extract and ascorbic acid had greatest protective effect against algae oil oxidation and generated four day lag phase, whereas rosmarinic acid, grape seed extract, grape seed extract polymer, deferoxamine (DFO), and ethylenediaminetetraacetic acid (EDTA) had no significant protective effect. Besides, there was no synergistic effect observed between natural antioxidants and ascorbic acid. The emulsifiers are critical to the physicochemical stability of water-in-algae oil emulsions. Polyglycerol polyricinoleate (PGPR) promoted the oxidation of emulsion. Conversely, the protective effect on algae oil oxidation was appreciated when defatted soybean lecithin (PC 75) or defatted lyso-lecithin (Lyso-PC) was added. The role of hydrophilic antioxidants in emulsion was similar to that in algae oil except EDTA which demonstrated strong antioxidative effect in emulsion. The results could provide information to build up stable food products containing polyunsaturated fatty acids (PUFA). Copyright © 2016 Elsevier Ltd. All rights reserved.

Aortic wall damage in mice unable to synthesize ascorbic acid

PubMed Central

Maeda, Nobuyo; Hagihara, Hiroyuki; Nakata, Yukiko; Hiller, Sylvia; Wilder, Jennifer; Reddick, Robert

2000-01-01

By inactivating the gene for l-gulono-γ-lactone oxidase, a key enzyme in ascorbic acid synthesis, we have generated mice that, like humans, depend on dietary vitamin C. Regular chow, containing about 110 mg/kg of vitamin C, is unable to support the growth of the mutant mice, which require l-ascorbic acid supplemented in their drinking water (330 mg/liter). Upon withdrawal of supplementation, plasma and tissue ascorbic acid levels decreased to 10–15% of normal within 2 weeks, and after 5 weeks the mutants became anemic, began to lose weight, and die. Plasma total antioxidative capacities were approximately 37% normal in homozygotes after feeding the unsupplemented diet for 3–5 weeks. As plasma ascorbic acid decreased, small, but significant, increases in total cholesterol and decreases in high density lipoprotein cholesterol were observed. The most striking effects of the marginal dietary vitamin C were alterations in the wall of aorta, evidenced by the disruption of elastic laminae, smooth muscle cell proliferation, and focal endothelial desquamation of the luminal surface. Thus, marginal vitamin C deficiency affects the vascular integrity of mice unable to synthesize ascorbic acid, with potentially profound effects on the pathogenesis of vascular diseases. Breeding the vitamin C-dependent mice with mice carrying defined genetic mutations will provide numerous opportunities for systematic studies of the role of antioxidants in health and disease. PMID:10639167

Aortic wall damage in mice unable to synthesize ascorbic acid.

PubMed

Maeda, N; Hagihara, H; Nakata, Y; Hiller, S; Wilder, J; Reddick, R

2000-01-18

By inactivating the gene for L-gulono-gamma-lactone oxidase, a key enzyme in ascorbic acid synthesis, we have generated mice that, like humans, depend on dietary vitamin C. Regular chow, containing about 110 mg/kg of vitamin C, is unable to support the growth of the mutant mice, which require L-ascorbic acid supplemented in their drinking water (330 mg/liter). Upon withdrawal of supplementation, plasma and tissue ascorbic acid levels decreased to 10-15% of normal within 2 weeks, and after 5 weeks the mutants became anemic, began to lose weight, and die. Plasma total antioxidative capacities were approximately 37% normal in homozygotes after feeding the unsupplemented diet for 3-5 weeks. As plasma ascorbic acid decreased, small, but significant, increases in total cholesterol and decreases in high density lipoprotein cholesterol were observed. The most striking effects of the marginal dietary vitamin C were alterations in the wall of aorta, evidenced by the disruption of elastic laminae, smooth muscle cell proliferation, and focal endothelial desquamation of the luminal surface. Thus, marginal vitamin C deficiency affects the vascular integrity of mice unable to synthesize ascorbic acid, with potentially profound effects on the pathogenesis of vascular diseases. Breeding the vitamin C-dependent mice with mice carrying defined genetic mutations will provide numerous opportunities for systematic studies of the role of antioxidants in health and disease.

Anti-oxidant behavior of functionalized chalcone-a combined quantum chemical and crystallographic structural investigation

NASA Astrophysics Data System (ADS)

Mathew, Bijo; Adeniyi, Adebayo A.; Joy, Monu; Mathew, Githa Elizabeth; Singh-Pillay, Ashona; Sudarsanakumar, C.; Soliman, Mahmoud E. S.; Suresh, Jerad

2017-10-01

Compound (2E)-3-(methoxyphenyl)-1-(4-methylphenyl) prop-2-en-1-one (Ch) was synthesized by the Claisen-Schmidt condensation reaction between para-methylacetophenone and para-methoxybenzaldehyde under basic condition. The structure of the molecule was elucidated using X-ray diffraction. Compound (Ch) demonstrated higher antioxidant activities in the DPPH test and H2O2 assay (IC50 = 12.23 ± 0.53 and 15.62 ± 0.98) than with the standard ascorbic acid (IC50 = 17.32 ± 0.44 and 19.07 ± 0.35). An evaluation of the atomic and molecular properties of ascorbic acid and Ch were computed based on their antioxidant activities. The molecular properties give insight into possible reasons for the enhanced antioxidant properties of Ch compared to ascorbic acid. The atomic properties provide further insight into chemical changes of the atoms of the compounds. Such changes include electronic shifting of the compounds electrophilic and/or nucleophilic states which highlight chemical moieties which characterize the antioxidant activity but do not directly relate to a variation in their antioxidant activities. The results obtained reflect oxygen atoms having significant nucleophilic interactions of each of the compounds. This was characterized by higher Fukui indices, isotropic and anisotropic hyperfine and orbital coupling stability energy.

Effects of water-soluble natural antioxidants on photosensitized oxidation of conjugated linoleic acid in an oil-in-water emulsion system.

PubMed

Liu, T-T; Yang, T-S

2008-05-01

The effect of photosensitized oxidation of conjugated linoleic acid in an oil-in-water (o/w) emulsion system was studied. Water-soluble natural antioxidants, including apple polyphenols from apple extract, green tea extract, 4-hydroxy-2(or 5)-ethyl-5(or2)-methyl-3(2H)-furanone(HEMF), 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF), and ascorbic acid, were tested for antioxidant activity in this system. The green tea extract showed the highest antioxidant activity followed by ascorbic acid. Apple polyphenols did not give significant antioxidant activity. HEMF and HDMF exhibited a prooxidant effect. The antioxidant activity of tea catechins was also investigated. Of them, EGCG and ECG exhibited antioxidant activity at 50 ppm, but the antioxidant activity between them was not significantly different (P < 0.05). Comparatively, EC, EGC, and GCG showed no significant antioxidative effect at 50 ppm. When the concentration increased to 100 ppm, the antioxidant activity of ECG and EGCG significantly increased compared with that at 50 ppm, and EGCG had higher antioxidant activity than ECG. GCG also showed significant antioxidant activity at 100 ppm. EGCG exhibited the highest antioxidant activity among the tea catechins in the emulsion system at 100 ppm.

Investigation of atmospheric oxidation of propyl gallate in an anionic surfactant system in the absence and presence of ascorbic acid.

PubMed

Szymula, M

2004-01-01

The antioxidant efficiency of two hydrophilic species, ascorbic acid (AA) and propyl gallate (PG), in an anionic surfactant system are studied. Ascorbic acid and propyl gallate are dissolved/solubilized in a microemulsion formed by water, pentanol, and sodium dodecyl sulfate. The determination of propyl gallate decomposition/oxidation kinetics shows enhanced oxidation of PG with increasing pentanol concentration in the system. When ascorbic acid and propyl gallate are both present in water, in surfactant aqueous solution, and in the studied microemulsion systems, the molecular complex AAPG is formed. After some time the complex decomposes.

Consumption of Hibiscus sabdariffa L. aqueous extract and its impact on systemic antioxidant potential in healthy subjects.

PubMed

Frank, Thomas; Netzel, Gabriele; Kammerer, Dietmar R; Carle, Reinhold; Kler, Adolf; Kriesl, Erwin; Bitsch, Irmgard; Bitsch, Roland; Netzel, Michael

2012-08-15

To evaluate health benefits attributed to Hibiscus sabdariffa L. a randomized, open-label, two-way crossover study was undertaken to compare the impact of an aqueous H. sabdariffa L. extract (HSE) on the systemic antioxidant potential (AOP; assayed by ferric reducing antioxidant power (FRAP)) with a reference treatment (water) in eight healthy volunteers. The biokinetic variables were the areas under the curve (AUC) of plasma FRAP, ascorbic acid and urate that are above the pre-dose concentration, and the amounts excreted into urine within 24 h (Ae(0-24) ) of antioxidants as assayed by FRAP, ascorbic acid, uric acid, malondialdehyde (biomarker for oxidative stress), and hippuric acid (metabolite and potential biomarker for total polyphenol intake). HSE caused significantly higher plasma AUC of FRAP, an increase in Ae(0-24) of FRAP, ascorbic acid and hippuric acid, whereas malondialdehyde excretion was reduced. Furthermore, the main hibiscus anthocyanins as well as one glucuronide conjugate could be quantified in the volunteers' urine (0.02% of the administered dose). The aqueous HSE investigated in this study enhanced the systemic AOP and reduced the oxidative stress in humans. Furthermore, the increased urinary hippuric acid excretion after HSE consumption indicates a high biotransformation of the ingested HSE polyphenols, most likely caused by the colonic microbiota. Copyright © 2012 Society of Chemical Industry.

Assessment of antioxidant capacities and phenolic contents of nigerian cultivars of onions (Allium cepa L) and garlic (Allium sativum L).

PubMed

Onyeoziri, Ukoha Pius; Romanus, Ekere Nwachukwu; Onyekachukwu, Uzodinma Irene

2016-07-01

This report assessed and compared the antioxidant potentials, quantities of ascorbic acid and phenolic compounds in methanolic extract of varieties of onions and garlic cultivars in Nigeria. The pH and total acidity of the extracts were equally determined. Antioxidancy of the cultivars were analysed using the in vitro assay techniques with 2,2-diphenyl-1-picryl Hydrazyl (DPPH) free radical scavenging and ferric reducing capacity. Ascorbic acid phenolic content were determined by volumetric and Folin-Ciocalteu's method respectively. The pH and total acidity were respectively 5.65 and 0.150mmol/L (red onion), 5.69 and 0.123mmol/L (white onion) and 6.94 and 0.105mmol/L (garlic). Red onion had the highest value of total phenols, ascorbic acid and free radical scavenging activity of 14.25±0.35mg GAE/ml, 229.098mg/100g, 66.44% respectively. In DPPH assay, red and white onion showed higher tendency to inhibit auto-oxidation when compared to garlic. The ferric reducing ability was greatest in garlic and least in white onions. These data indicate that with respect to antioxidant activity, red onion variety has highest health promoting potential among others.

Antioxidant Prophylaxis in the Prevention of Prostatic Epithelial Neoplasia

DTIC Science & Technology

2007-02-01

additional year until the end of March 2008. 105Co-enzyme Q10 105Grape seed extract 31.5Alpha Lipoic acid 10.5Lutein 10.5Lycopene...antioxidants used in the study. Ascorbic acid is a potent antioxidant that interacts synergistically with Lipoic acid to destroy many types of free radicals...co-enzyme Q10. Lycopene and lutein are fat soluble carotenoids that work synergistically and possess very high antioxidant activity. Lipoic acid not

Supplemental vitamin C appears to slow racing greyhounds.

PubMed

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

2002-06-01

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

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

PubMed

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

2017-01-01

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

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

PubMed Central

de la Torre, Daniel

2008-01-01

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

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

PubMed

de la Torre, Daniel

2008-12-14

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

Antioxidant capacity of different broccoli (Brassica oleracea) genotypes using the oxygen radical absorbance capacity (ORAC) assay.

PubMed

Kurilich, Anne C; Jeffery, Elizabeth H; Juvik, John A; Wallig, Matthew A; Klein, Barbara P

2002-08-28

Antioxidant capacity of hydrophilic and lipophilic extracts from eight broccoli genotypes was compared using the oxygen radical absorbance capacity (ORAC) assay. Each genotype was analyzed for carotenoid, tocopherol, ascorbic acid, and flavonoid content. Results indicate that the antioxidant capacity of hydrophilic extracts ranged from 65.8 to 121.6 micromol trolox equivalents (TE)/g of tissue, and the capacity of lipophilic extracts ranged from 3.9 to 17.5 micromol TE/g. Ascorbic acid and flavonoid content of the hydrophilic extracts did not explain the total variation in antioxidant capacity of those extracts, suggesting either the presence of other antioxidant components that have yet to be identified or that the known antioxidants are producing synergistic effects. The carotenoids did correlate with antioxidant capacity of the lipophilic extracts and accounted for the majority of the variability in that fraction. The variability in hydrophilic and lipophilic antioxidant capacity found among these genotypes suggests that potential efficacy from antioxidants will vary considerably from genotype to genotype.

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

PubMed

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

2002-07-01

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

Phytochemicals and antioxidant activity of fruits and leaves of paprika (Capsicum Annuum L., var. special) cultivated in Korea.

PubMed

Kim, Ji-Sun; Ahn, Jiyun; Lee, Sung-Joon; Moon, Bokyung; Ha, Tae-Youl; Kim, Suna

2011-03-01

The phytochemical composition of carotenoids, tocopherols, free sugars, organic acids, L-ascorbic acid, capsaicinoids, and flavonoids in green and red paprika (GP and RP), and paprika leaves (PL) cultivated in Korea were analyzed. The ethanolic extracts of GP, RP, and PL were obtained with 80% ethanol, and their antioxidative activities were determined by measuring their ABTS and DPPH radical scavenging activities. RP showed the highest contents of capsanthin (58.33 ± 3.91 mg/100 g dry weight) and L-ascorbic acid (1987.25 ± 19.64 mg/100 g dry weight), and main compounds of PL were lutein, chlorophyll, and γ-tocopherol (96.91 ± 14.58, 2136.71 ± 21.11, and 723.49 ± 54.10 mg/100 g dry weight, respectively). RP showed the strongest antioxidant activity (IC(50) = 55.23 ± 6.77 μg/mL in a 2, 2'-azino-di-[3-ethylbenzthiazoline sulphonate] assay and 150.40 ± 8.07 μg/mL in a 2, 2-diphenyl-2-picrylhydrazyl assay), and the antioxidant activity of PL was higher than β-carotene but lower than RP. The results indicate that the amounts of capsanthin and L-ascorbic acid in RP correlate well with antioxidant activity. PL, which has various phytochemicals such as lutein, chlorophyll, and γ-tocopherol, might be used in nutraceuticals and pharmaceuticals for improving human health.

Phenolic antioxidants from the leaves of Corchorus olitorius L.

PubMed

Azuma, K; Nakayama, M; Koshioka, M; Ippoushi, K; Yamaguchi, Y; Kohata, K; Yamauchi, Y; Ito, H; Higashio, H

1999-10-01

Six phenolic antioxidative compounds [5-caffeoylquinic acid (chlorogenic acid), 3,5-dicaffeoylquinic acid, quercetin 3-galactoside, quercetin 3-glucoside, quercetin 3-(6-malonylglucoside), and quercetin 3-(6-malonylgalactoside) (tentative)] were identified from the leaves of Corchorus olitorius L. (moroheiya) by NMR and FAB-MS. The contents of these phenolic compounds, ascorbic acid, and alpha-tocopherol in C. olitorius leaves were determined, and their antioxidative activities were measured using the radical generator-initiated peroxidation of linoleic acid. The results obtained showed that 5-caffeoylquinic acid was a predominant phenolic antioxidant in C. olitorius leaves.

Ascorbate as a Biosynthetic Precursor in Plants

PubMed Central

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

2007-01-01

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

Evolution of antioxidant capacity during storage of selected fruits and vegetables.

PubMed

Kevers, Claire; Falkowski, Michael; Tabart, Jessica; Defraigne, Jean-Olivier; Dommes, Jacques; Pincemail, Joël

2007-10-17

Interest in the consumption of fresh fruits and vegetables is, to a large extent, due to its content of bioactive nutrients and their importance as dietary antioxidants. Among all of the selected fruits and vegetables, strawberries and black grapes have relatively high antioxidant capacities associated with high contents of total phenolic compounds, ascorbic acid, and flavonols. More interesting, the results of this study indicated that in most fruits and vegetables storage did not affect negatively the antioxidant capacity. Better, in some cases, an increase of the antioxidant capacity was observed in the days following their purchase, accompanied by an increase in phenolic compounds. In general, fruits and vegetables visually spoil before any significant antioxidant capacity loss occurs except in banana and broccoli. When ascorbic acid or flavonoids (aglycons of flavonols and anthocyanins) were concerned, the conclusions were similar. Their content was generally stable during storage.

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

EPA Science Inventory

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

Influence of dried Hokkaido pumpkin and ascorbic acid addition on chemical properties and colour of corn extrudates.

PubMed

Obradović, Valentina; Babić, Jurislav; Šubarić, Drago; Jozinović, Antun; Ačkar, Đurđica; Klarić, Ilija

2015-09-15

The influence of Hokkaido pumpkin powder (PP) addition to corn grits at levels 4%, 6%, and 8% and ascorbic acid (AA) addition at levels 0.5% and 1% was evaluated. Extrusion was done using a single-screw extruder at two temperature regimes: 135/170/170°C (E1) and 100/150/150°C (E2). Mathematical models that describe the influence of additives on the colour of extrudates were determined. Raw extrusion mixtures as well as obtained extrudates were tested for ascorbic acid, polyphenol, proteins, fat, crude fibre, ash and carotenoids content, and antioxidant activity. E1 extrusion regime acted favourably on polyphenols, crude fibre content, and antioxidant activity. It also caused higher fat degradation than E2 extrusion. Xanthophylls (lutein and zeaxanthin) were less sensitive to extrusion than carotenes (α-carotene, 9-cis-β-carotene and 13-cis-β-carotene). Ascorbic acid was more sensitive to higher extrusion temperatures (49-76% degradation). It provided protection to carotenoids and consequently the colour of the extrudates. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

PubMed

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

2013-05-22

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

Betalain, Acid Ascorbic, Phenolic Contents and Antioxidant Properties of Purple, Red, Yellow and White Cactus Pears

PubMed Central

Sumaya-Martínez, María Teresa; Cruz-Jaime, Sandra; Madrigal-Santillán, Eduardo; García-Paredes, Juan Diego; Cariño-Cortés, Raquel; Cruz-Cansino, Nelly; Valadez-Vega, Carmen; Martinez-Cardenas, Leonardo; Alanís-García, Ernesto

2011-01-01

Commercialization of cactus pears based on their antioxidant properties can generate competitive advantages, and these can turn into business opportunities and the development of new products and a high-value ingredient for the food industry. This work evaluated the antioxidant activities (1,1-diphenyl-2-picrylhydrazyl radical-scavenging, protection against oxidation of a β-carotene-linoleic acid emulsion, and iron (II) chelation), the content of total phenolic compounds, ascorbic acid, betacyanin, betaxanthin and the stability of betacyanin pigments in presence of Cu (II)-dependent hydroxyl radicals (OH•), in 18 cultivars of purple, red, yellow and white cactus pear from six Mexican states. Our results indicated that the antiradical activities from yellow and white cactus pear cultivars were not significantly different (p < 0.05) and were lower than the average antiradical activities in red and purple cultivars. The red cactus pear from the state of Zacatecas showed the highest antioxidant activity. The free radical scavenging activity for red cactus pears was significantly correlated (p < 0.05) to the concentration of total phenolic compounds (R2 = 0.90) and ascorbic acid (R2 = 0.86). All 18 cultivars of cactus pears studied showed significant chelating activity of ferrous ions. The red and purple cactus pears showed a great stability when exposed to OH•. PMID:22072899

Reaction Kinetics of Phenolic Antioxidants toward Photoinduced Pyranine Free Radicals in Biological Models.

PubMed

Aspée, Alexis; Aliaga, Christian; Maretti, Luca; Zúñiga-Núñez, Daniel; Godoy, Jessica; Pino, Eduardo; Cárdenas-Jirón, Gloria; Lopez-Alarcon, Camilo; Scaiano, Juan C; Alarcon, Emilio I

2017-07-06

8-Hydroxy-1,3,6-pyrenetrisulfonic acid (pyranine, PyOH) free radicals were induced by laser excitation at visible wavelengths (470 nm). The photochemical process involves photoelectron ejection from PyO- to produce PyO• and PyO•- with maxima absorption at 450 and 510 nm, respectively. The kinetic rate constants for phenolic antioxidants with PyO•, determined by nanosecond time-resolved spectroscopy, were largely reliant on the ionic strength depending on the antioxidant phenol/phenolate dissociation constant. Further, the apparent rate constant measured in the presence of Triton X100 micelles was influenced by the antioxidant partition between the micelle and the dispersant aqueous media but limited by its exit rates from the micelle. Similarly, the rate reaction between ascorbic acid and PyO• was markedly affected by the presence of human serum albumin responding to the dynamic of the ascorbic acid binding to the protein.

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

PubMed

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

2017-10-01

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

Polyphenolic content and antioxidant activity of some wild Saudi Arabian Asteraceae plants.

PubMed

Shahat, Abdelaaty A; Ibrahim, Abeer Y; Elsaid, Mansour S

2014-07-01

To study the antioxidant properties of crude extract of different Asteraceae plants. The antioxidant properties of six extracts were evaluated using different antioxidant tests, including free radical scavenging, reducing power, metal chelation, superoxide anion radical scavenging, total antioxidant capacity and inhibition of lipid peroxidation activities. Picris cyanocarpa (P. cyanocarpa) and Anthemis deserti (A. deserti) had powerful antioxidant properties as radical scavenger, reducing agent and superoxide anion radical scavenger while Achillia fragrantissima (A. fragrantissima) and Artemissia monosperma (A. monosperma) were the most efficient as ion chelator (100% at 100, 200 and 400 μg/mL) A. fragrantissima and Rhantarium appoposum (R. appoposum) showed 100% inhibition on peroxidation of linoleic acid emulsion at 200 and 400 μg/mL, while butylatedhydroxy toluene and ascorbic acid showed 100 and 95% inhibition percentage at 400 μg/mL, respectively. Those various antioxidant activities were compared to standard antioxidants such as butylated hydroxyl toluene and ascorbic acid. In most tests P. cyanocarpa and A. deserti had powerful antioxidant properties as radical scavenger, reducing agent and superoxide anion radical scavenger. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Comparison of ozone-specific (OZAC) and oxygen radical (ORAC) antioxidant capacity assays for use with nasal lavage fluid.

PubMed

Rutkowski, Joseph M; Santiag, Lizzie Y; Ben-Jebria, Abdellaziz; Ultman, James S

2011-10-01

Antioxidants in respiratory mucus protect the underlying airway epithelium from damage by ozone (O(3)), a common outdoor air pollutant. To understand O(3)-antioxidant interactions and the variation of these interactions among individuals, in vitro assays are needed to measure the total antioxidant capacity of airway lavage fluid, a convenient source of (diluted) mucous samples. Here, we compare the oxygen radical absorbance capacity (ORAC), a general method that uses peroxyl radicals as a reactive substance, to the recently developed ozone specific antioxidant capacity (OZAC), a procedure that directly employs O(3). For prepared model mucous antioxidant solutions containing uric acid, ascorbic acid or glutathione, the ORAC and OZAC methods yielded comparable antioxidant capacities. The addition of EDTA or DETAPAC, necessary to prevent auto-oxidation of test solutions during the ORAC assay, unpredictably altered ORAC measurements. EDTA did not have a significant effect on OZAC measurements in either prepared uric acid or ascorbic acid solutions. When assessing antioxidant capacities of nasal lavage samples, the ORAC and OZAC assays were no longer comparable. Because the OZAC of nasal lavage samples was positively related to measured uric acid concentrations whereas the ORAC data were not, the OZAC method appears to provide more realistic mucous antioxidant capacities than the ORAC method. Copyright © 2011 Elsevier Ltd. All rights reserved.

Sclerotial biomass and carotenoid yield of Penicillium sp. PT95 under oxidative growth conditions and in the presence of antioxidant ascorbic acid.

PubMed

Li, X L; Cui, X H; Han, J R

2006-09-01

To determine the effect of oxidative stress and exogenous ascorbic acid on sclerotial biomass and carotenoid yield of Penicillium sp. PT95. In this experiment, high oxidative stress was applied by the inclusion of FeSO(4) in the growth medium and exposure to light. Low oxidative stress was applied by omitting iron from the growth medium and by incubation in the dark. Supplementation of exogenous ascorbic acid (as antioxidant) to the basal medium caused a concentration-dependent delay of sclerotial differentiation (up to 48 h), decrease of sclerotial biomass (up to 40%) and reduction of carotenoid yield (up to 91%). On the contrary, the exogenous ascorbic acid also caused a concentration-dependent decrease of lipid peroxidation in colonies of this fungus. Under high oxidative stress growth condition, the sclerotial biomass and carotenoid yield of PT95 strain in each plate culture reached 305 mg and 32.94 microg, which were 1.23 and 3.71 times higher, respectively, than those at low oxidative stress growth condition. These data prompted us to consider that in order to attain higher sclerotial biomass and pigment yield, the strain PT95 should be grown under high oxidative stress and in the absence of antioxidants. These results suggest that strain PT95 may be used for solid-state fermentation of carotenoid production under high oxidative stress growth conditions.

Spectroscopic studies on the antioxidant activity of p-coumaric acid

NASA Astrophysics Data System (ADS)

Kiliç, Ismail; Yeşiloğlu, Yeşim

2013-11-01

p-coumaric acid (4-hydroxycinnamic acid), a phenolic acid, is a hydroxyl derivative of cinnamic acid. It decreases low density lipoprotein (LDL) peroxidation and reduces the risk of stomach cancer. In vitro radical scavenging and antioxidant capacity of p-coumaric acid were clarified using different analytical methodologies such as total antioxidant activity determination by ferric thiocyanate, hydrogen peroxide scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, 2,2‧-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity and superoxide anion radical scavenging, ferrous ions (Fe2+) chelating activity and ferric ions (Fe3+) reducing ability. p-Coumaric acid inhibited 71.2% lipid peroxidation of a linoleic acid emulsion at 45 μg/mL concentration. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and ascorbic acid displayed 66.8%, 69.8%, 64.5% and 59.7% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, p-coumaric acid had an effective DPPHrad scavenging, ABTSrad + scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power and ferrous ions (Fe2+) chelating activities. Also, those various antioxidant activities were compared to BHA, BHT, α-tocopherol and ascorbic acid as references antioxidant compounds. These results suggested that p-coumaric acid can be used in the pharmacological and food industry because of these properties.

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

USDA-ARS?s Scientific Manuscript database

The hydrolytic and oxidative stability of L-(+)-ascorbic acid (AA) into plasticized pectin films were separately studied in view of preserving vitamin C activity and/or to achieve localized antioxidant activity at pharmaceutical and food interfaces. Films were made with each one of the enzymatically...

An in vitro model to test relative antioxidant potential: Ultraviolet-induced lipid peroxidation in liposomes

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

Pelle, E.; Maes, D.; Padulo, G.A.

1990-12-01

Since antioxidants have been shown to play a major role in preventing some of the effects of aging and photoaging in skin, it is important to study this phenomenon in a controlled manner. This was accomplished by developing a simple and reliable in vitro technique to assay antioxidant efficacy. Inhibition of peroxidation by antioxidants was used as a measure of relative antioxidant potential. Liposomes, high in polyunsaturated fatty acids (PUFA), were dispersed in buffer and irradiated with ultraviolet (UV) light. Irradiated liposomes exhibited a significantly higher amount of hydroperoxides than liposomes containing antioxidants in a dose- and concentration-dependent manner. Lipidmore » peroxidation was determined spectrophotometrically by an increase in thiobarbituric acid reacting substances. To further substantiate the production of lipid peroxides, gas chromatography was used to measure a decrease in PUFA substrate. In order of decreasing antioxidant effectiveness, the following results were found among lipophilic antioxidants: BHA greater than catechin greater than BHT greater than alpha-tocopherol greater than chlorogenic acid. Among hydrophilic antioxidants, ascorbic acid and dithiothreitol were effective while glutathione was ineffective. In addition, ascorbic acid was observed to act synergistically with alpha-tocopherol, which is in agreement with other published reports on the interaction of these two antioxidants. Although peroxyl radical scavengers seem to be at a selective advantage in this liposomal/UV system, these results demonstrate the validity of this technique as an assay for measuring an antioxidant's potential to inhibit UV-induced peroxidation.« less

The effect of high-pressure processing on colour, bioactive compounds, and antioxidant activity in smoothies during refrigerated storage.

PubMed

Andrés, Víctor; Villanueva, María J; Tenorio, María D

2016-02-01

The effects of high-pressure processing--HPP--(450 and 600 MPa/3 min/20 °C) on the colour, carotenoids, ascorbic acid, polyphenols and antioxidant activity (FRAP and DPPH) of a smoothie were compared to thermal processing (80 °C/3 min). Stability during 45 days at 4 °C was also evaluated. HPP samples showed slight differences (p < 0.05) in colour compared to untreated smoothies. Both HPP significantly increased the extractability of lycopene, β-carotene and polyphenols compared to untreated samples. After HPP, ascorbic acid was retained by more than 92% of the initial content. The best results for antioxidant activity were obtained when HPP was applied at 600 MPa. FRAP and DPPH showed a high correlation with ascorbic acid (R(2) = 0.7135 and 0.8107, respectively) and polyphenolic compounds (R(2) = 0.6819 and 0.6935, respectively), but not with total carotenoids. Changes in bioactive compounds during the storage period were lower in the HPP smoothie than in the thermal-treated sample. Copyright © 2015 Elsevier Ltd. All rights reserved.

Antioxidant properties of selected fruit cultivars grown in Sri Lanka.

PubMed

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

2018-01-01

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

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

PubMed

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

2009-04-01

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

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

PubMed Central

2012-01-01

Background An increased interest is given to the impact of high fat diet on health worldwide. Abnormalities in lipid metabolism induced by high cholesterol diet (HCD) were reported to exacerbate renal diseases via oxidative stress pathways. Rutin and ascorbic acid showed a protective role against oxidative stress-mediated diseases. Furthermore, both lipid metabolism and tissue response to oxidative stress damage was found to vary according to animal gender. Thus, the objective of this work was to examine possible gender-related differences and the possible protective effects of rutin and ascorbic acid supplementation on high cholesterol diet induced nephrotoxicity. Methods 96 young male and female Wistar albino rats were used. HCD supplemented animals were treated with rutin alone or in combination with ascorbic acid for 6 weeks. Creatinine plasma level was estimated. Furthermore, kidney levels of nucleic acids, total protein, malondialdehyde (MDA), reduced glutathione (GSH), total cholesterol, and triglycerides were determined. Finally, kidney tissues were used for histopathological examination. Results HCD supplementation decreased kidney level of nucleic acids, which was more prominent in female animals. Both vitamin combination significantly attenuated HCD induced decrease in nucleic acids. Moreover, kidney level of MDA was significantly altered by HCD in both genders, which was inhibited by rutin and ascorbic acid alone or in combination in male groups and by both vitamins in female groups. There was a reduction in kidney level of GSH by HCD, especially in male groups, which was attenuated by rutin and ascorbic acid combination. Kidney levels of total cholesterol and triglycerides were significantly increased by HCD supplementation in both genders. Coadministration with rutin and/or ascorbic acid protected from such increase, which was more obvious in both vitamins combination. Histopathological investigation supported vitamins protective effect, which was more prominent in male vitamins combination group. Conclusions HCD-induced renal injury in female was higher than in male animals, suggesting a better anti-oxidative stress defense response in male's kidney. Moreover, the antioxidant and reno-protective effects of rutin and ascorbic acid were augmented following their combination. PMID:22423898

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

PubMed

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

2012-03-16

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

Antioxidant protective effect of flavonoids on linoleic acid peroxidation induced by copper(II)/ascorbic acid system.

PubMed

Beker, Bilge Yıldoğan; Bakır, Temelkan; Sönmezoğlu, Inci; Imer, Filiz; Apak, Reşat

2011-11-01

Antioxidants are compounds that can delay or inhibit lipid oxidation. The peroxidation of linoleic acid (LA) in the absence and presence of Cu(II) ion-ascorbate combinations was investigated in aerated and incubated emulsions at 37°C and pH 7. LA peroxidation induced by copper(II)-ascorbic acid system followed first order kinetics with respect to hydroperoxides concentration. The extent of copper-initiated peroxide production in a LA system assayed by ferric thiocyanate method was used to determine possible antioxidant and prooxidant activities of the added flavonoids. The effects of three different flavonoids of similar structure, i.e. quercetin (QR), morin (MR) and catechin (CT), as potential antioxidant protectors were studied in the selected peroxidation system. The inhibitive order of flavonoids in the protection of LA peroxidation was: morin>catechin≥quercetin, i.e. agreeing with that of formal reduction potentials versus NHE at pH 7, i.e. 0.60, 0.57 and 0.33V for MR, CT, and QR, respectively. Morin showed antioxidant effect at all concentrations whereas catechin and quercetin showed both antioxidant and prooxidant effects depending on their concentrations. The structural requirements for antioxidant activity in flavonoids interestingly coincide with those for Cu(II)-induced prooxidant activity, because as the reducing power of a flavonoid increases, Cu(II)-Cu(I) reduction is facilitated that may end up with the production of reactive species. The findings of this study were evaluated in the light of structure-activity relationships of flavonoids, and the results are believed to be useful to better understand the actual conditions where flavonoids may act as prooxidants in the preservation of heterogeneous food samples containing traces of transition metal ions. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Spectroscopic studies on the antioxidant activity of ellagic acid

NASA Astrophysics Data System (ADS)

Kilic, Ismail; Yeşiloğlu, Yeşim; Bayrak, Yüksel

2014-09-01

Ellagic acid (EA, C14H6O8) is a natural dietary polyphenol whose benefits in a variety of diseases shown in epidemiological and experimental studies involve anti-inflammation, anti-proliferation, anti-angiogenesis, anticarcinogenesis and anti-oxidation properties. In vitro radical scavenging and antioxidant capacity of EA were clarified using different analytical methodologies such as total antioxidant activity determination by ferric thiocyanate, hydrogen peroxide scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, 2,2‧-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity and superoxide anion radical scavenging, ferrous ions (Fe2+) chelating activity and ferric ions (Fe3+) reducing ability. EA inhibited 71.2% lipid peroxidation of a linoleic acid emulsion at 45 μg/mL concentration. On the other hand, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), α-tocopherol and ascorbic acid displayed 69.8%, 66.8%, 64.5% and 59.7% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, EA had an effective DPPH• scavenging, ABTSrad + scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power and ferrous ions (Fe2+) chelating activities. Also, those various antioxidant activities were compared to BHA, BHT, α-tocopherol and ascorbic acid as references antioxidant compounds. These results suggested that EA can be used in the pharmacological, food industry and medicine because of these properties.

Effects of brown seaweed polyphenols, α-tocopherol, and ascorbic acid on protein oxidation and textural properties of fish mince (Pagrosomus major) during frozen storage.

PubMed

Wang, Tiantian; Li, Zhenxing; Yuan, Fangzhou; Lin, Hong; Pavase, Tushar Ramesh

2017-03-01

Frozen storage of minced fish is currently one of the most important techniques to maintain its functional properties. However, some deterioration does occur during frozen storage and cause quality loss. The effects of brown seaweed polyphenols, α-tocopherol, and ascorbic acid on lipid and protein oxidation and textural properties of red sea bream (Pagrosomus major) during 90 days of frozen storage at -18 °C were investigated. All added antioxidants at 1 g kg -1 resulted in significantly lower thiobarbituric acid-reactive substances (TBARS) compared to the control during the 45 days of frozen storage. The antioxidants were also effective in retarding protein oxidation concerning to total sulfhydryl content and protein carbonyl content. Brown seaweed polyphenols and α-tocopherol significantly retarded the inactivation of Ca 2+ -ATPase activity during the first 45 days, whereas ascorbic acid had no such effect. The antioxidant activity showed either an invariable or decrease trend after 45 days storage. Adding antioxidants had a significant effect on the breaking force of the gels during the frozen storage period. These results indicate that brown seaweed polyphenols and α-tocopherol can be used to prevent oxidative reactions and thus maintain the structure of the gel formed by fish mince during frozen storage. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Sugars, ascorbic acid, total phenolic content and total antioxidant activity in passion fruit (Passiflora) cultivars.

PubMed

Devi Ramaiya, Shiamala; Bujang, Japar Sidik; Zakaria, Muta Harah; King, Wong Sing; Shaffiq Sahrir, Muhd Arif

2013-03-30

The levels of sugars, ascorbic acid, total phenolic content (TPC) and total antioxidant activity (TAA) were determined in fruit juices from seven passion fruit (Passiflora spp.) cultivars: P. edulis cultivars Purple, Frederick, Yellow, Pink, P. edulis f. flavicarpa, P. maliformis and P. quadrangularis (we also tested this cultivar's mesocarp). Purple and Yellow P. edulis had significantly higher total sugar, 142.85 ± 0.17 g kg⁻¹ and 139.69 ± 0.12 g kg⁻¹, respectively, than other cultivars. Glucose and fructose content were higher in juice from vine-ripened fruits of Purple, Frederick and Yellow P. edulis, P. quadrangularis and P. maliformis. Sucrose content was significantly higher in juice of non-vine-ripened fruits of P. edulis (Pink) and P. edulis f. flavicarpa. Ascorbic acid, TPC and TAA were significantly higher in vine-ripened Purple and Yellow P. edulis; ranges were 0.22-0.33 g kg⁻¹, 342.80-382.00 mg gallic acid equivalent L⁻¹ and 409.13-586.70 µmol Trolox L⁻¹, respectively. Based on principal component analysis (PCA) and cluster analysis, the main variables - °Brix, total sugar, glucose, fructose, ascorbic acid, TPC and TAA - formed the characteristics for the group comprising Purple and Yellow P. edulis. Glucose, fructose, sucrose, ascorbic acid, TAA and TPC were quantified in passion fruit juices. Variation of the above variables in juices of Passiflora depends on the cultivar and ripeness. © 2012 Society of Chemical Industry.

IN VITRO MEASUREMENT OF TOTAL ANTIOXIDANT CAPACITY OF CRATAEGUS MACRACANTHA LODD LEAVES.

PubMed

Miftode, Alina Monica; Stefanache, Alina; Spac, A F; Miftode, R F; Miron, Anca; Dorneanu, V

2016-01-01

Crataegus macracantha Lodd, family Rosaceae, is a very rare species in Europe, and unlike Crataegus monogyna is less investigated for pharmacologic activity. To analyze the ability of the lyophilisate of extract obtained from leaves of Crataegus macracantha Lodd (single plant at the Iaşi Botanical Garden) to capture free radicals in vitro. The lyophilisate obtained in Department of Pharmacognosy, Faculty of Pharmacy, "Grigore T. Popa" University of Medicine and Pharmacy Iaşi. The decreased absorbance of chromophore chlorpromazine radical cation in the presence of the lyophilized solutions was studied spectrophotometrically. The indicator radical cation, obtained by oxidation of chlorpromazine by potassium persulfate, has the maximum absorbance at 525 nm. Ascorbic acid was used as a standard antioxidant. The absorbance of radical solution was determined after the addition of a certain amount of lyophilisate at different time intervals. The antioxidant activity was calculated using the calibration curve obtained by plotting the variation in radical solution absorbance depending on ascorbic acid concentration. For each ascorbic acid concentration the area under the curve was calculated from plotting the percentage inhibition of the absorbance at two pre-established time intervals. The results confirm the antioxidant activity of the leaves of Crataegus Macracantha Lodd and by optimizing the proposed analytical methods the antiradical activity can be quickly evaluated with minimal reagent consumption.

Physicochemical and antioxidant properties of Bangladeshi honeys stored for more than one year

PubMed Central

2012-01-01

Background There is no available information on physicochemical and antioxidant properties on Bangladeshi honey. We investigated five different monofloral and three different multifloral honey samples collected from different parts of Bangladesh. Methods The levels of phenolics, flavonoids, ascorbic acid, ascorbic acid equivalent antioxidant content (AEAC), proline, protein and antioxidants were determined in the honey samples using ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays. Results The highest level of phenolic was 688.5 ± 5.9 mg Gallic acid/kg, and the highest level of flavonoid was 155 ± 6.9 mg Catechin/kg. The highest color intensity was 2034.00 ± 17.5 mAU, and the highest protein content was 8.6 ± 0.0mg/g. High levels of proline (2932.8 ± 3.7 mg/kg), ascorbic acid (154.3 ± 0.3 mg/kg), AEAC (34.1 ± 1.4mg/100 g) and FRAP (772.4 ± 2.5 μmol Fe (II)/100 g) were detected in some of the samples, especially the multifloral honey samples, indicating good antioxidant properties. A strong positive correlation was found between phenolics, flavonoids, DPPH, FRAP and color intensity, indicating that in addition to total phenolic and flavonoid concentrations, color intensity and amino acid are good indicators of the antioxidant potential of honey. Except for a single sample (BDH-6), the honey samples stored for 1.5 years at room temperature still had 5-hydroxymethylfurfural (HMF) values within the recommended range (mean = 10.93 mg/kg), indicating that the rate of HMF production in Bangladeshi honey samples is low. Conclusion It is postulated that the low rate of HMF formation could be attributed to the acidic and low moisture content in the samples. In general, multifloral honeys have higher antioxidant properties based on their high levels of phenolics, flavonoids, AEAC, DPPH and FRAP when compared to monofloral honeys. We also found that monofloral honey samples from Guizotia abyssinica and Nigella sativa had high antioxidant properties. PMID:23043497

Physicochemical and antioxidant properties of Bangladeshi honeys stored for more than one year.

PubMed

Islam, Asiful; Khalil, Ibrahim; Islam, Nazmul; Moniruzzaman, Mohammed; Mottalib, Abdul; Sulaiman, Siti Amrah; Gan, Siew Hua

2012-10-08

There is no available information on physicochemical and antioxidant properties on Bangladeshi honey. We investigated five different monofloral and three different multifloral honey samples collected from different parts of Bangladesh. The levels of phenolics, flavonoids, ascorbic acid, ascorbic acid equivalent antioxidant content (AEAC), proline, protein and antioxidants were determined in the honey samples using ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays. The highest level of phenolic was 688.5 ± 5.9 mg Gallic acid/kg, and the highest level of flavonoid was 155 ± 6.9 mg Catechin/kg. The highest color intensity was 2034.00 ± 17.5 mAU, and the highest protein content was 8.6 ± 0.0mg/g. High levels of proline (2932.8 ± 3.7 mg/kg), ascorbic acid (154.3 ± 0.3 mg/kg), AEAC (34.1 ± 1.4mg/100 g) and FRAP (772.4 ± 2.5 μmol Fe (II)/100 g) were detected in some of the samples, especially the multifloral honey samples, indicating good antioxidant properties. A strong positive correlation was found between phenolics, flavonoids, DPPH, FRAP and color intensity, indicating that in addition to total phenolic and flavonoid concentrations, color intensity and amino acid are good indicators of the antioxidant potential of honey. Except for a single sample (BDH-6), the honey samples stored for 1.5 years at room temperature still had 5-hydroxymethylfurfural (HMF) values within the recommended range (mean = 10.93 mg/kg), indicating that the rate of HMF production in Bangladeshi honey samples is low. It is postulated that the low rate of HMF formation could be attributed to the acidic and low moisture content in the samples. In general, multifloral honeys have higher antioxidant properties based on their high levels of phenolics, flavonoids, AEAC, DPPH and FRAP when compared to monofloral honeys. We also found that monofloral honey samples from Guizotia abyssinica and Nigella sativa had high antioxidant properties.

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

PubMed

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

2006-04-01

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

Spectroscopic studies on the antioxidant activity of p-coumaric acid.

PubMed

Kiliç, Ismail; Yeşiloğlu, Yeşim

2013-11-01

p-coumaric acid (4-hydroxycinnamic acid), a phenolic acid, is a hydroxyl derivative of cinnamic acid. It decreases low density lipoprotein (LDL) peroxidation and reduces the risk of stomach cancer. In vitro radical scavenging and antioxidant capacity of p-coumaric acid were clarified using different analytical methodologies such as total antioxidant activity determination by ferric thiocyanate, hydrogen peroxide scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity and superoxide anion radical scavenging, ferrous ions (Fe(2+)) chelating activity and ferric ions (Fe(3+)) reducing ability. p-Coumaric acid inhibited 71.2% lipid peroxidation of a linoleic acid emulsion at 45μg/mL concentration. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and ascorbic acid displayed 66.8%, 69.8%, 64.5% and 59.7% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, p-coumaric acid had an effective DPPH scavenging, ABTS(+) scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe(3+)) reducing power and ferrous ions (Fe(2+)) chelating activities. Also, those various antioxidant activities were compared to BHA, BHT, α-tocopherol and ascorbic acid as references antioxidant compounds. These results suggested that p-coumaric acid can be used in the pharmacological and food industry because of these properties. Copyright © 2013 Elsevier B.V. All rights reserved.

Influence of cultivar and ripening time on bioactive compounds and antioxidant properties in Cape gooseberry (Physalis peruviana L.).

PubMed

Bravo, Karent; Sepulveda-Ortega, Stella; Lara-Guzman, Oscar; Navas-Arboleda, Alejandro A; Osorio, Edison

2015-05-01

Cape gooseberry (Physalis peruviana) is an exotic fruit highly valued for its organoleptic properties and bioactive compounds. Considering that the presence of phenolics and ascorbic acid could contribute to its functional capacity, it is important to investigate the quality parameters, bioactive contents and functional properties with respect to genotype and ripening time. In this study the genotype effect was evaluated in 15 cultivars for two different harvest times. Changes during maturation were recorded in two commercial cultivars within seven levels of maturity. Multivariate statistical analysis suggested that phenolic content and ORAC value were mainly affected by harvest time and that ascorbic acid content and DPPH level were mainly affected by genotype. In addition, acidity, phenolic content, ORAC value and inhibition of LDL oxidation decreased with maturity, but soluble solids content, ascorbic acid content, β-carotene content and DPPH-scavenging activity were higher in mature fruits. The phenolic content, ascorbic acid content and antioxidant properties of Cape gooseberry fruit were strongly affected by cultivar, harvest time and maturity state. Consequently, the harvest time must be scheduled carefully to gain the highest proportion of bioactive compounds according to the specific cultivar and the environment where it is grown. © 2014 Society of Chemical Industry.

Antioxidative effect of melatonin, ascorbic acid and N-acetylcysteine on caerulein-induced pancreatitis and associated liver injury in rats

PubMed Central

Eşrefoğlu, Mukaddes; Gül, Mehmet; Ateş, Burhan; Batçıoğlu, Kadir; Selimoğlu, Mukadder Ayşe

2006-01-01

AIM: To investigate the role of oxidative injury in pancreatitis-induced hepatic damage and the effect of antioxidant agents such as melatonin, ascorbic acid and N-acetyl cysteine on caerulein-induced pancreatitis and associated liver injury in rats. METHODS: Thirty-eight female Wistar rats were used. Acute pancreatitis (AP) was induced by two i.p. injections of caerulein at 2-h intervals (at a total dose of 100 µg/kg b.wt). The other two groups received additional melatonin (20 mg/kg b.wt) or an antioxidant mixture containing L(+)-ascorbic acid (14.3 mg/kb.wt.) and N-acetyl cysteine (181 mg/kg b.wt.) i.p. shortly before each injection of caerulein. The rats were sacrificed by decapitation 12 h after the last injection of caerulein. Pancreatic and hepatic oxidative stress markers were evaluated by changes in the amount of lipid peroxides measured as malondialdehyde (MDA) and changes in tissue antioxidant enzyme levels, catalase (CAT) and glutathione peroxidase (GPx). Histopathological examination was performed using scoring systems. RESULTS: The degree of hepatic cell degeneration, intracellular vacuolization, vascular congestion, sinusoidal dilatation and inflammatory infiltration showed a significant difference between caerulein and caerulein + melatonin (P  = 0.001), and careulein and caerulein + L(+)-ascorbic acid + N-acetyl cysteine groups (P  = 0.002). The degree of aciner cell degeneration, pancreatic edema, intracellular vacuolization and inflammatory infiltration showed a significant difference between caerulein and caerulein + melatonin (P  = 0.004), and careulein and caerulein + L(+)-ascorbic acid + N-acetyl cysteine groups (P = 0.002). Caerulein-induced pancreatic and liver damage was accompanied with a significant increase in tissue MDA levels (P  = 0.01, P  = 0.003, respectively) whereas a significant decrease in CAT (P  = 0.002, P = 0.003, respectively) and GPx activities (P  = 0.002, P  = 0.03, respectively). Melatonin and L(+)-ascorbic acid + N-acetyl cysteine administration significantly decreased MDA levels in pancreas (P  = 0.03, P  = 0.002, respectively) and liver (P  = 0.007, P  = 0.01, respectively). Administration of these agents increased pancreatic and hepatic CAT and GPx activities. Melatonin significantly increased pancreatic and hepatic CAT (P  = 0.002, P  = 0.001, respectively) and GPx activities (P  = 0.002, P  = 0.001). Additionally, L(+)-ascorbic acid+N-acetyl cysteine significantly increased pancreatic GPx (P  = 0.002) and hepatic CAT and GPx activities (P  = 0.001, P  = 0.007, respectively) CONCLUSION: Oxidative injury plays an important role not only in the pathogenesis of AP but also in pancreatitis-induced hepatic damage. Antioxidant agents such as melatonin and ascorbic acid + N-acetyl cysteine, are capable of limiting pancreatic and hepatic damage produced during AP via restoring tissue antioxidant enzyme activities. PMID:16482627

Colored potatoes (Solanum tuberosum L.) dried into antioxidant-rich value-added foods

USDA-ARS?s Scientific Manuscript database

Colored potatoes (Solanum tuberosum L.) are a significant source of antioxidants from polyphenols, carotenoids, tocopherol and ascorbic acid. In this study, retention of total antioxidants in fresh colored potatoes and processed potato flakes prepared as potential ingredients for snack foods was stu...

Antioxidant activity and total phenolic content of ethanolic extract of Caesalpinia bonducella seeds.

PubMed

Shukla, Shruti; Mehta, Archana; John, Jinu; Singh, Siddharth; Mehta, Pradeep; Vyas, Suresh Prasad

2009-08-01

The aim of this study was to assess the in vitro potential of ethanolic extract of Caesalpinia bonducella seeds as a natural antioxidant. The DPPH activity of the extract (20, 40, 50, 100 and 200 microg/ml) was increased in a dose dependent manner, which was found in the range of 38.93-74.77% as compared to ascorbic acid (64.26-82.58%). The IC(50) values of ethanolic extract and ascorbic acid in DPPH radical scavenging assay were obtained to be 74.73 and 26.68 microg/ml, respectively. The ethanolic extract was also found to scavenge the superoxide generated by EDTA/NBT system. Measurement of total phenolic content of the ethanolic extract of C. bonducella was achieved using Folin-Ciocalteau reagent containing 62.50mg/g of phenolic content, which was found significantly higher when compared to reference standard gallic acid. The ethanolic extract also inhibited the hydroxyl radical, nitric oxide, superoxide anions with IC(50) values of 109.85, 102.65 and 89.84 microg/ml, respectively. However, the IC(50) values for the standard ascorbic acid were noted to be 70.79, 65.98 and 36.68 microg/ml respectively. The results obtained in this study clearly indicate that C. bonducella has a significant potential to use as a natural antioxidant agent.

Beyond the redox imbalance: oxidative stress contributes to an impaired GLUT3 modulation in Huntington's disease

PubMed Central

Covarrubias-Pinto, Adriana; Moll, Pablo; Solís-Maldonado, Macarena; Acuña, Aníbal I.; Riveros, Andrea; Miró, María Paz; Papic, Eduardo; Beltrán, Felipe A.; Cepeda, Carlos; Concha, Ilona I.; Brauchi, Sebastián; Castro, Maite A.

2016-01-01

Failure in energy metabolism and oxidative damage are associated with Huntington’s disease (HD). Ascorbic acid released during synaptic activity inhibits use of neuronal glucose, favouring lactate uptake to sustain brain activity. Here, we observe a decreased expression of GLUT3 in STHdhQ111 cells (HD cells) and R6/2 mice (HD mice). Localisation of GLUT3 is decreased at the plasma membrane in HD cells affecting the modulation of glucose uptake by ascorbic acid. An ascorbic acid analogue without antioxidant activity is able to inhibit glucose uptake in HD cells. The impaired modulation of glucose uptake by ascorbic acid is directly related to ROS levels indicating that oxidative stress sequesters the ability of ascorbic acid to modulate glucose utilisation. Therefore, in HD, a decrease in GLUT3 localisation at the plasma membrane would contribute to an altered neuronal glucose uptake during resting periods while redox imbalance should contribute to metabolic failure during synaptic activity. PMID:26456058

Reduction of protein radicals by GSH and ascorbate: potential biological significance.

PubMed

Gebicki, Janusz M; Nauser, Thomas; Domazou, Anastasia; Steinmann, Daniel; Bounds, Patricia L; Koppenol, Willem H

2010-11-01

The oxidation of proteins and other macromolecules by radical species under conditions of oxidative stress can be modulated by antioxidant compounds. Decreased levels of the antioxidants glutathione and ascorbate have been documented in oxidative stress-related diseases. A radical generated on the surface of a protein can: (1) be immediately and fully repaired by direct reaction with an antioxidant; (2) react with dioxygen to form the corresponding peroxyl radical; or (3) undergo intramolecular long range electron transfer to relocate the free electron to another amino acid residue. In pulse radiolysis studies, in vitro production of the initial radical on a protein is conveniently made at a tryptophan residue, and electron transfer often leads ultimately to residence of the unpaired electron on a tyrosine residue. We review here the kinetics data for reactions of the antioxidants glutathione, selenocysteine, and ascorbate with tryptophanyl and tyrosyl radicals as free amino acids in model compounds and proteins. Glutathione repairs a tryptophanyl radical in lysozyme with a rate constant of (1.05±0.05)×10(5) M(-1) s(-1), while ascorbate repairs tryptophanyl and tyrosyl radicals ca. 3 orders of magnitude faster. The in vitro reaction of glutathione with these radicals is too slow to prevent formation of peroxyl radicals, which become reduced by glutathione to hydroperoxides; the resulting glutathione thiyl radical is capable of further radical generation by hydrogen abstraction. Although physiologically not significant, selenoglutathione reduces tyrosyl radicals as fast as ascorbate. The reaction of protein radicals formed on insulin, β-lactoglobulin, pepsin, chymotrypsin and bovine serum albumin with ascorbate is relatively rapid, competes with the reaction with dioxygen, and the relatively innocuous ascorbyl radical is formed. On the basis of these kinetics data, we suggest that reductive repair of protein radicals may contribute to the well-documented depletion of ascorbate in living organisms subjected to oxidative stress.

Endogenous ROS levels are increased in replicative senescence in human bone marrow mesenchymal stromal cells.

PubMed

Jeong, Sin-Gu; Cho, Goang-Won

2015-05-15

Cellular senescence is characterized by functional decline induced by cumulative damage to DNA, proteins, lipids, and carbohydrates. Previous studies have reported that replicative senescence is caused by excessive amounts of reactive oxygen species (ROS) produced as a result of aerobic energy metabolism. In this study, we established human bone marrow mesenchymal stromal cells (hBM-MSCs) in replicative senescence after culture over a long term to investigate the relationship between ROS levels and stem cell potential and to determine whether differentiation potential can be restored by antioxidant treatment. Intracellular ROS levels were increased in hBM-MSCs; this was accompanied by a decrease in the expression of the antioxidant enzymes catalase and superoxide dismutase (SOD)1 and 2 and of phosphorylated forkhead box O1 (p-FOXO1) as well as an increase in the expression of p53 and p16, along with a reduction in differentiation potential. When the antioxidant ascorbic acid was used to eliminate excess ROS, the levels of antioxidant enzymes (catalase, SOD1 and 2, p-FOXO1, and p53) were partly restored. Moreover, differentiation into adipocytes and osteocytes was higher in hBM-MSCs treated with ascorbic acid than in the untreated control cells. These results suggest that the decline in differentiation potential caused by increased endogenous ROS production during in vitro expansion can be reversed by treatment with antioxidants such as ascorbic acid. Copyright © 2015 Elsevier Inc. All rights reserved.

Trypsin Inhibitors from Cajanus cajan and Phaseolus limensis Possess Antioxidant, Anti-Inflammatory, and Antibacterial Activity.

PubMed

Shamsi, Tooba Naz; Parveen, Romana; Afreen, Sumbul; Azam, Mudasser; Sen, Priyankar; Sharma, Yamini; Haque, Qazi Mohd Rizwanul; Fatma, Tasneem; Manzoor, Nikhat; Fatima, Sadaf

2018-01-18

Protease inhibitors are one of the most promising and investigated subjects for their role in pharmacognostic and pharmacological studies. This study aimed to investigate antioxidant, anti-inflammatory, and antimicrobial activities of trypsin inhibitors (TIs) from two plant sources (Cajanus cajan and Phaseolus limensis). TI was purified from C. cajan (PUSA-992) by ammonium sulfate precipitation followed by ion exchange chromatography. TI from Phaseolus limensis (lima bean trypsin inhibitor; LBTI) was procured from Sigma-Aldrich, St. Louis, Missouri, United States. The antioxidant activity was analyzed by ferric ion reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH). The anti-inflammatory property of TIs was determined by inhibition of albumin denaturation assay. Ascorbic acid and aspirin were used as standards for antioxidant and anti-inflammatory assays, respectively. These TIs were tested against various bacterial and fungal strains. The TIs showed DPPH radical-scavenging activity in a concentration-dependent manner with IC 50 values comparable to ascorbic acid. The FRAP values were also observed comparable to ascorbic acid and followed the trend of dose-dependent manner. The half maximal inhibitory concentration (IC 50 ) values of CCTI and LBTI in anti-inflammatory test showed that LBTI is more potent than CCTI. The TIs showed potent antibacterial activity, but apparently no action against fungi. This study has reported the biological properties of CCTI and LBTI for the first time. The results show that TIs possess the ability to inhibit diseases caused by oxidative stress, inflammation, and bacterial infestation.

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

PubMed

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

2009-01-01

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

Ascorbic acid is the only bioactive that is better preserved by high hydrostatic pressure than by thermal treatment of a vegetable beverage.

PubMed

Barba, Francisco J; Esteve, Maria J; Frigola, Ana

2010-09-22

Variations in levels of antioxidant compounds (ascorbic acid, total phenolics, and total carotenoids), total antioxidant capacity, and color changes in a vegetable (tomato, green pepper, green celery, onion, carrot, lemon, and olive oil) beverage treated by high hydrostatic pressure (HHP) were evaluated in this work. The effects of HHP treatment, four different pressures (100, 200, 300, and 400 MPa) and four treatment times for each pressure (from 120 to 540 s) were compared with those of thermal treatment (90-98 °C for 15 and 21 s). High pressure treatment retained significantly more ascorbic acid in the vegetable beverage than thermal treatment. However, no significant changes in total phenolics were observed between HHP treated and thermally processed vegetable beverage and unprocessed beverage. Color changes (a*, b*, L, chroma, h°, and ΔE) were less for pressurized beverage than thermally treated samples compared with unprocessed beverage.

Combined Effects of Lanthanum (III) and Acid Rain on Antioxidant Enzyme System in Soybean Roots.

PubMed

Zhang, Xuanbo; Du, Yuping; Wang, Lihong; Zhou, Qing; Huang, Xiaohua; Sun, Zhaoguo

2015-01-01

Rare earth element pollution (REEs) and acid rain (AR) pollution simultaneously occur in many regions, which resulted in a new environmental issue, the combined pollution of REEs and AR. The effects of the combined pollution on the antioxidant enzyme system of plant roots have not been reported. Here, the combined effects of lanthanum ion (La3+), one type of REE, and AR on the antioxidant enzyme system of soybean roots were investigated. In the combined treatment of La3+ (0.08 mM) and AR, the cell membrane permeability and the peroxidation of cell membrane lipid of soybean roots increased, and the superoxide dismutase, catalase, peroxidase and reduced ascorbic acid served as scavengers of reactive oxygen species. In other combined treatments of La3+ (0.40 mM, 1.20 mM) and AR, the membrane permeability, malonyldialdehyde content, superoxide dismutase activity, peroxidase activity and reduced ascorbic acid content increased, while the catalase activity decreased. The increased superoxide dismutase activity, peroxidase activity and reduced ascorbic acid content were inadequate to scavenge the excess hydrogen peroxide and superoxide, leading to the damage of the cell membrane, which was aggravated with the increase in the concentration of La3+ and the level of AR. The deleterious effects of the combined treatment of La3+ and AR were stronger than those of the single treatment of La3+ or AR. Moreover, the activity of antioxidant enzyme system in the combined treatment group was affected directly and indirectly by mineral element content in soybean plants.

Combined Effects of Lanthanum (III) and Acid Rain on Antioxidant Enzyme System in Soybean Roots

PubMed Central

Zhang, Xuanbo; Du, Yuping; Wang, Lihong; Zhou, Qing; Huang, Xiaohua; Sun, Zhaoguo

2015-01-01

Rare earth element pollution (REEs) and acid rain (AR) pollution simultaneously occur in many regions, which resulted in a new environmental issue, the combined pollution of REEs and AR. The effects of the combined pollution on the antioxidant enzyme system of plant roots have not been reported. Here, the combined effects of lanthanum ion (La3+), one type of REE, and AR on the antioxidant enzyme system of soybean roots were investigated. In the combined treatment of La3+ (0.08 mM) and AR, the cell membrane permeability and the peroxidation of cell membrane lipid of soybean roots increased, and the superoxide dismutase, catalase, peroxidase and reduced ascorbic acid served as scavengers of reactive oxygen species. In other combined treatments of La3+ (0.40 mM, 1.20 mM) and AR, the membrane permeability, malonyldialdehyde content, superoxide dismutase activity, peroxidase activity and reduced ascorbic acid content increased, while the catalase activity decreased. The increased superoxide dismutase activity, peroxidase activity and reduced ascorbic acid content were inadequate to scavenge the excess hydrogen peroxide and superoxide, leading to the damage of the cell membrane, which was aggravated with the increase in the concentration of La3+ and the level of AR. The deleterious effects of the combined treatment of La3+ and AR were stronger than those of the single treatment of La3+ or AR. Moreover, the activity of antioxidant enzyme system in the combined treatment group was affected directly and indirectly by mineral element content in soybean plants. PMID:26230263

Effect of Freeze-Drying on the Antioxidant Compounds and Antioxidant Activity of Selected Tropical Fruits

PubMed Central

Shofian, Norshahida Mohamad; Hamid, Azizah Abdul; Osman, Azizah; Saari, Nazamid; Anwar, Farooq; Dek, Mohd Sabri Pak; Hairuddin, Muhammad Redzuan

2011-01-01

The effects of freeze-drying on antioxidant compounds and antioxidant activity of five tropical fruits, namely starfruit (Averrhoa carambola L.), mango (Mangifera indica L.), papaya (Carica papaya L.), muskmelon (Cucumis melo L.), and watermelon Citruluss lanatus (Thunb.) were investigated. Significant (p < 0.05) differences, for the amounts of total phenolic compounds (TPC), were found between the fresh and freeze-dried fruit samples, except muskmelon. There was no significant (p > 0.05) change, however, observed in the ascorbic acid content of the fresh and freeze-dried fruits. Similarly, freeze-drying did not exert any considerable effect on β-carotene concentration of fruits, except for mango and watermelon, where significantly (p < 0.05) higher levels were detected in the fresh samples. The results of DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging and reducing power assays revealed that fresh samples of starfruit and mango had relatively higher antioxidant activity. In case of linoleic acid peroxidation inhibition measurement, a significant (p < 0.05) but random variation was recorded between the fresh and freeze-dried fruits. Overall, in comparison to β-carotene and ascorbic acid, a good correlation was established between the result of TPC and antioxidant assays, indicating that phenolics might have been the dominant compounds contributing towards the antioxidant activity of the fruits tested. PMID:21845104

Effect of freeze-drying on the antioxidant compounds and antioxidant activity of selected tropical fruits.

PubMed

Shofian, Norshahida Mohamad; Hamid, Azizah Abdul; Osman, Azizah; Saari, Nazamid; Anwar, Farooq; Dek, Mohd Sabri Pak; Hairuddin, Muhammad Redzuan

2011-01-01

The effects of freeze-drying on antioxidant compounds and antioxidant activity of five tropical fruits, namely starfruit (Averrhoa carambola L.), mango (Mangifera indica L.), papaya (Carica papaya L.), muskmelon (Cucumis melo L.), and watermelon Citruluss lanatus (Thunb.) were investigated. Significant (p < 0.05) differences, for the amounts of total phenolic compounds (TPC), were found between the fresh and freeze-dried fruit samples, except muskmelon. There was no significant (p > 0.05) change, however, observed in the ascorbic acid content of the fresh and freeze-dried fruits. Similarly, freeze-drying did not exert any considerable effect on β-carotene concentration of fruits, except for mango and watermelon, where significantly (p < 0.05) higher levels were detected in the fresh samples. The results of DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging and reducing power assays revealed that fresh samples of starfruit and mango had relatively higher antioxidant activity. In case of linoleic acid peroxidation inhibition measurement, a significant (p < 0.05) but random variation was recorded between the fresh and freeze-dried fruits. Overall, in comparison to β-carotene and ascorbic acid, a good correlation was established between the result of TPC and antioxidant assays, indicating that phenolics might have been the dominant compounds contributing towards the antioxidant activity of the fruits tested.

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

PubMed

Zhao, Rong; Holmgren, Arne

2004-02-01

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

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

PubMed

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

2004-02-01

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

Minimization of free radical damage by metal catalysis of multivitamin/multimineral supplements.

PubMed

Rabovsky, Alexander B; Komarov, Andrei M; Ivie, Jeremy S; Buettner, Garry R

2010-11-23

Multivitamin/multimineral complexes are the most common dietary supplements. Unlike minerals in foods that are incorporated in bioorganic structures, minerals in dietary supplements are typically in an inorganic form. These minerals can catalyze the generation of free radicals, thereby oxidizing antioxidants during digestion. Here we examine the ability of a matrix consisting of an amino acid and non-digestible oligosaccharide (AAOS) to blunt metal-catalyzed oxidations. Monitoring of ascorbate radical generated by copper shows that ascorbate is oxidized more slowly with the AAOS matrix than with copper sulfate. Measurement of the rate of oxidation of ascorbic acid and Trolox® by catalytic metals confirmed the ability of AAOS to slow these oxidations. Similar results were observed with iron-catalyzed formation of hydroxyl radicals. When compared to traditional forms of minerals used in supplements, we conclude that the oxidative loss of antioxidants in solution at physiological pH is much slower when AAOS is present.

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

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

Lee, E.H.

1991-01-01

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

Effect of Germination and Fermentation Process on the Antioxidant Compounds of Quinoa Seeds.

PubMed

Carciochi, Ramiro Ariel; Galván-D'Alessandro, Leandro; Vandendriessche, Pierre; Chollet, Sylvie

2016-12-01

Quinoa (Chenopodium quinoa) seed has gained a great interest in the last years, mainly due to its nutritional properties and its content of antioxidant substances with health-promoting properties in humans. In this work, the effect of germination time and fermentation on the levels of antioxidant compounds (ascorbic acid, tocopherol isomers and phenolic compounds) and antioxidant activity of quinoa seeds was evaluated. Fermentation was carried out naturally by the microorganisms present in the seeds or by inoculation with two Saccharomyces cerevisiae strains (used for baking and brewing). Ascorbic acid and total tocopherols were significantly increased (p ≤ 0.05) after 72 h of germination process in comparison with raw quinoa seeds, whilst fermentation caused a decrease in both types of compounds. Phenolic compounds and antioxidant capacity were improved using both bioprocesses, being this effect more noticeable for germination process (101 % of increase after three days of germination). Germination and fermentation proved to be desirable procedures for producing enriched ingredients with health-promoting antioxidant compounds in a natural way.

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

PubMed

Pappenberger, Günter; Hohmann, Hans-Peter

2014-01-01

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

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

PubMed

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

2013-06-01

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

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

PubMed

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

2006-01-01

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

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

PubMed

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

2002-12-01

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

Novel total antioxidant capacity index for dietary polyphenols and vitamins C and E, using their cupric ion reducing capability in the presence of neocuproine: CUPRAC method.

PubMed

Apak, Resat; Güçlü, Kubilay; Ozyürek, Mustafa; Karademir, Saliha Esin

2004-12-29

The chemical diversity of antioxidants makes it difficult to separate and quantify antioxidants from the vegetable matrix. Therefore, it is desirable to establish a method that can measure the total antioxidant activity level directly from vegetable extracts. The current literature clearly states that there is no "total antioxidant" as a nutritional index available for food labeling because of the lack of standard quantitation methods. Thus, this work reports the development of a simple, widely applicable antioxidant capacity index for dietary polyphenols and vitamins C and E, utilizing the copper(II)-neocuproine [Cu(II)-Nc] reagent as the chromogenic oxidizing agent. Because the copper(II) (or cupric) ion reducing ability of polyphenols is measured, the method is named by our research group "cupric reducing antioxidant capacity" abbreviated as the CUPRAC method. This method should be advantageous over the ferric reducing antioxidant power (FRAP) method because the redox chemistry of copper(II)-as opposed to that of ferric ion-involves faster kinetics. The method comprises mixing of the antioxidant solution (directly or after acid hydrolysis) with a copper(II) chloride solution, a neocuproine alcoholic solution, and an ammonium acetate aqueous buffer at pH 7 and subsequent measurement of the developed absorbance at 450 nm after 30 min. Because the color development is fast for compounds such as ascorbic acid, gallic acid, and quercetin but slow for naringin and naringenin, the latter compounds were assayed after incubation at 50 degrees C on a water bath for 20 min [after Cu(II)-Nc reagent addition] so as to force the oxidation reaction to reach completion. The flavonoid glycosides were hydrolyzed to their corresponding aglycons by refluxing in 1.2 M HCl-containing 50% MeOH so as to exert maximal reducing power toward Cu(II)-Nc. Certain compounds also needed incubation after acid hydrolysis to fully exhibit their reducing capability. The CUPRAC antioxidant capacities of synthetic mixtures of antioxidants were experimentally measured as Trolox equivalents and compared to those theoretically found by making use of the principle of additivity of absorbances assuming no chemical interaction between the mixture constituents. Because ascorbic acid is not resistant to elevated temperature incubation, it should be assayed initially by measuring the absorbance (at 450 nm) difference of original and ascorbate oxidase-added mixture solutions at the end of 1 min of Cu(II)-Nc reagent addition. Thus, the total CUPRAC antioxidant capacity of a mixture containing various antioxidants should be that finally measured after a suitable combination of hydrolysis and incubation procedures, added to the initially measured capacity due to ascorbate. The antioxidant polyphenolic compounds tested demonstrate that the highest capacities in the CUPRAC method were observed for epicatechin gallate, epigallocatechin gallate, quercetin, fisetin, epigallocatechin, catechin, and caffeic acid in this order, in accordance with theoretical expectations, because the number and position of the hydroxyl groups as well as the degree of conjugation of the whole molecule are important. The antioxidant potency of flavonoids is nearly proportional to the total number of -OH groups and is positively affected by the presence of an o-dihydroxy moiety in the B-ring. beta-Carotene, which did not react with the CUPRAC reagent in alcoholic aqueous medium, could be assayed in dichloromethane solvent. Linear calibration curves for ascorbic acid and flavonoids were redrawn in synthetic solutions containing a mixture of antioxidants, and also in real matrices such as grape and orange juices, green tea, and blackberry tea, showing an initial nonzero absorbance with the CUPRAC reagent. The parallellism of the linear calibration curves of pure compounds in a given complex matrix effectively demonstrated that there were no interferent chemical interactions among the solution constituents and that the antioxidant capacities of the tested antioxidants were additive. The CUPRAC reagent is reasonably selective, stable, easily accessible, and sensitive toward thiol-type oxidants, unlike the FRAP method. The reaction is carried out at nearly physiological pH as opposed to the unrealistic acidic pH of FRAP.

Ascorbate and homoglutathione metabolism in common bean nodules under stress conditions and during natural senescence.

PubMed

Loscos, Jorge; Matamoros, Manuel A; Becana, Manuel

2008-03-01

Ascorbate and glutathione are major antioxidants and redox buffers in plant cells but also play key functions in growth, development, and stress responses. We have studied the regulation of ascorbate and homoglutathione biosynthesis in common bean (Phaseolus vulgaris) nodules under stress conditions and during aging. The expression of five genes of the major ascorbate biosynthetic pathway was analyzed in nodules, and evidence was found that L-galactono-1,4-lactone dehydrogenase, the last committed step of the pathway, is posttranscriptionally regulated. Also, in nodules under stress conditions, gamma-glutamylcysteine synthetase was translationally regulated, but homoglutathione synthetase (mRNA and activity) and homoglutathione (content and redox state) were not affected. Most interestingly, in nodules exposed to jasmonic acid, dehydroascorbate reductase activity was posttranslationally suppressed, ascorbate oxidase showed strong transcriptional up-regulation, and dehydroascorbate content increased moderately. These changes were not due to a direct effect of jasmonic acid on the enzyme activities but might be part of the signaling pathway in the response of nodules to stress. We determined ascorbate, homoglutathione, and ascorbate-glutathione pathway enzyme activities in two senescing stages of nodules undergoing oxidative stress. When all parameters were expressed on a nodule fresh weight basis, we found that in the first stage ascorbate decreased by 60% and homoglutathione and antioxidant activities remained fairly constant, whereas in the second stage ascorbate and homoglutathione, their redox states, and their associated enzyme activities significantly decreased. The coexistence in the same plants of nodules at different senescence stages, with different ascorbate concentrations and redox states, indicates that the life span of nodules is in part controlled by endogenous factors and points to ascorbate as one of the key players.

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

PubMed Central

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

2013-01-01

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

Antioxidant Activities of Achyranthes japonica Nakai Extract and Its Application to the Pork Sausages.

PubMed

Park, J H; Kang, S N; Shin, D; Hur, I C; Kim, I S; Jin, S K

2013-02-01

Influence of Achyranthes japonica Nakai Extract (AJNE) on properties of pork sausages were studied in the present investigation. AJNE was added to sausages alone or in combination with ascorbic acid to obtain a comparative analysis on properties of control and ascorbic acid added-sausages. Results showed that addition of 0.05% AJNE led to a decrease in color L* and whiteness (W), and an increase in color b* of pork sausage samples (p<0.05). Although color a* of pork sausages containing AJNE was not significantly different, ascorbic acid added-sausages were highest amongst other treatments (p<0.05). Sausages containing AJNE had lower non-heme iron values and peroxide value (POV) than control sausages (p<0.05); however, high nitrosomyoglobin content was observed in AJNE added-sausages (p<0.05). Ascorbic acid led to a decrease in residual nitrite concentration of sausages (p<0.05), but no difference was found in AJNE added-sausages. Free radical scavenging analysis showed that AJNE did not affect 1,1-diphenyl -2-picrylhydrazyl (DPPH) activity of sausages, whereas ascorbic acid added-sausages showed relatively higher activity among the samples (p<0.05). Addition of AJNE had no influence on texture properties of sausages. In sensory evaluation, AJNE treatment had significant effects on color (p<0.05), but no significant effects on aroma, flavor, springiness, juiciness, and overall acceptability. In conclusion, the addition of AJNE, as a natural supplement may offer natural antioxidants for pork sausages, and appears to be particularly effective in inducing changes in non-heme iron concentration, POV value and nitrosomyglobin content.

Antioxidant Activities of Achyranthes japonica Nakai Extract and Its Application to the Pork Sausages

PubMed Central

Park, J. H.; Kang, S. N.; Shin, D.; Hur, I. C.; Kim, I. S.; Jin, S. K.

2013-01-01

Influence of Achyranthes japonica Nakai Extract (AJNE) on properties of pork sausages were studied in the present investigation. AJNE was added to sausages alone or in combination with ascorbic acid to obtain a comparative analysis on properties of control and ascorbic acid added-sausages. Results showed that addition of 0.05% AJNE led to a decrease in color L* and whiteness (W), and an increase in color b* of pork sausage samples (p<0.05). Although color a* of pork sausages containing AJNE was not significantly different, ascorbic acid added-sausages were highest amongst other treatments (p<0.05). Sausages containing AJNE had lower non-heme iron values and peroxide value (POV) than control sausages (p<0.05); however, high nitrosomyoglobin content was observed in AJNE added-sausages (p<0.05). Ascorbic acid led to a decrease in residual nitrite concentration of sausages (p<0.05), but no difference was found in AJNE added-sausages. Free radical scavenging analysis showed that AJNE did not affect 1,1-diphenyl -2-picrylhydrazyl (DPPH) activity of sausages, whereas ascorbic acid added-sausages showed relatively higher activity among the samples (p<0.05). Addition of AJNE had no influence on texture properties of sausages. In sensory evaluation, AJNE treatment had significant effects on color (p<0.05), but no significant effects on aroma, flavor, springiness, juiciness, and overall acceptability. In conclusion, the addition of AJNE, as a natural supplement may offer natural antioxidants for pork sausages, and appears to be particularly effective in inducing changes in non-heme iron concentration, POV value and nitrosomyglobin content. PMID:25049789

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

PubMed

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

2015-03-01

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

Effect of astaxanthin in combination with alpha-tocopherol or ascorbic acid against oxidative damage in diabetic ODS rats.

PubMed

Nakano, Masako; Onodera, Aya; Saito, Emi; Tanabe, Miyako; Yajima, Kazue; Takahashi, Jiro; Nguyen, Van Chuyen

2008-08-01

The present study was performed to investigate the effect of astaxanthin in combination with other antioxidants against oxidative damage in streptozotocin (STZ)-induced diabetic Osteogenic Disorder Shionogi (ODS) rats. Diabetic-ODS rats were divided into five groups: control, astaxanthin, ascorbic acid, alpha-tocopherol, and tocotrienol. Each of the four experimental groups was administered a diet containing astaxanthin (0.1 g/kg), in combination with ascorbic acid (3.0 g/kg), alpha-tocopherol (0.1 g/kg), or tocotrienol (0.1 g/kg) for 20 wk. The effects of astaxanthin with other antioxidants on lipid peroxidation, urinary 8-hydroxy-2-deoxyguanosine (8-OHdG) excretion, serum creatinine (Cr) level, creatinine clearance (Ccr), and urinary protein content were assessed. The serum lipid peroxide levels and chemiluminescent (CL) intensity in the liver of the alpha-tocopherol and tocotrienol groups were significantly reduced in comparison to that of the control group. In the alpha-tocopherol group, urinary 8-OHdG excretion, serum Cr level, Ccr, urinary albumin excretion, and urinary protein concentration were significantly decreased as compared with those in the control group. Additionally, the CL intensity in the kidney of the alpha-tocopherol group was significantly lower, but that of the ascorbic acid group was significantly higher than that in the control group. These results indicate that dietary astaxanthin in combination with alpha-tocopherol has an inhibitory effect on oxidative stress. On the other hand, our study suggests that excessive ascorbic acid intake increases lipid peroxidation in diabetic rats.

New antioxidant treatment with yerba mate ( Ilex paraguariensis) infusion for fresh-cut apples: Modeling, optimization, and acceptability.

PubMed

Rodríguez-Arzuaga, Mariana; Piagentini, Andrea M

2018-04-01

Enzymatic browning affects the sensory and nutritional quality of fresh-cut apples and limits their shelf-life. Yerba mate ( Ilex paraguariensis), a plant widely consumed in South America as an infusion, could potentially be used in minimally processed fruits and vegetables as a natural additive to prevent browning, due to its high content of phenolic compounds with antioxidant capacity. The effects of the concentrations of ascorbic acid, citric acid, and yerba mate in an aqueous dipping solution on the instrumental color parameters, antioxidant capacity, and sensory quality of "Granny Smith" fresh-cut apples were modeled and the solution was optimized to obtain treated apples with maximum antioxidant capacity and minimum browning, without affecting the natural flavor of the fruits. The optimal composition obtained (1.2% yerba mate  + 0.9% citric acid + 1.0% ascorbic acid) increased the antioxidant capacity of the apples by 36%. The sensory acceptability test carried out on the "Granny Smith" fresh-cut apples treated with the optimal dipping solution showed that more than 78% of the surveyed consumers liked the color, flavor, and texture of the apples.

Comparison of the Effects of Blending and Juicing on the Phytochemicals Contents and Antioxidant Capacity of Typical Korean Kernel Fruit Juices

PubMed Central

Pyo, Young-Hee; Jin, Yoo-Jeong; Hwang, Ji-Young

2014-01-01

Four Korean kernel fruit (apple, pear, persimmon, and mandarin orange) juices were obtained by household processing techniques (i.e., blending, juicing). Whole and flesh fractions of each fruit were extracted by a blender or a juicer and then examined for phytochemical content (i.e., organic acids, polyphenol compounds). The antioxidant capacity of each juice was determined by ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. Results revealed that juices that had been prepared by blending whole fruits had stronger antioxidant activities and contained larger amounts of phenolic compounds than juices that had been prepared by juicing the flesh fraction of the fruit. However, the concentration of ascorbic acid in apple, pear, and mandarin orange juices was significantly (P<0.05) higher in juice that had been processed by juicing, rather than blending. The juices with the highest ascorbic acid (233.9 mg/serving), total polyphenols (862.3 mg gallic acid equivalents/serving), and flavonoids (295.1 mg quercetin equivalents/serving) concentrations were blended persimmon juice, blended mandarin orange juice, and juiced apple juice, respectively. These results indicate that juice extraction techniques significantly (P<0.05) influences the phytochemical levels and antioxidant capacity of fruit juices. PMID:25054109

Effect of drying methods with the application of vacuum microwaves on the bioactive compounds, color, and antioxidant activity of strawberry fruits.

PubMed

Wojdyło, Aneta; Figiel, Adam; Oszmiański, Jan

2009-02-25

The objective of this study was to evaluate the application of vacuum-microwave drying (240, 360, and 480 W) in the production process of dehydrated strawberry and to compare and contrast the quality of these dehydrated strawberries in terms of their polyphenol compounds, concentration of some heat liable components, and color to that of freeze-dried, convective, and vacuum-dried strawberry. Thus, the effect of vacuum-microwave drying and other drying methods on the antioxidant activity of berries was evaluated. Whole fresh and dried fruits were assessed for phenolics (anthocyanins, flavanols, hydroxycinnamic acids, and flavonols), ascorbic acid, and antioxidant activity (all parameters were calculated on a dry matter basis). Analysis of data shows that ellagic acid and flavanol changes were affected by drying techniques and cultivar. Drying destroyed anthocyanins, flavanols, and ascorbic acid, and there was a significant decrease in antioxidant activity. The most striking result was that conventional and vacuum drying decreased antioxidant activity in both cultivars, whereas contradictory results were found for vacuum-microwave processed strawberry. This study has demonstrated that vacuum-microwave drying, especially at 240 W, can produce high-quality products, with the additional advantage of reduced processing times, compared to other processes such as freeze-drying.

Vitamin C: update on physiology and pharmacology

PubMed Central

Mandl, J; Szarka, A; Bánhegyi, G

2009-01-01

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

Antioxidant activities of tocopherols on Fe2+-ascorbate-induced lipid peroxidation in lecithin liposomes.

PubMed

Fukuzawa, K; Tokumura, A; Ouchi, S; Tsukatani, H

1982-07-01

The antioxidant activities of 4 tocopherols, tocol, and a water-soluble model analog of alpha-tocopherol were compared. Egg lecithin liposomes were used and oxidation was catalyzed by Fe2+-ascorbate. The activities decreased in the order alpha greater than beta greater than gamma greater than delta-tocopherol greater than tocol, in agreement with their potencies in vivo. The water-soluble analog was the least effective. Activity depended on the molar ratio of antioxidant to unsaturated lipid, with one molecule each of the alpha-, beta-, gamma-, delta-tocopherol and tocol capable of protecting, respectively, 220, 120, 100, 30 and 20 molecules of polyunsaturated fatty acid. The mechanism of possible antioxidant effect of the compounds used is discussed.

Biosynthesis of silver nanoparticles using Alternanthera sessilis (Linn.) extract and their antimicrobial, antioxidant activities.

PubMed

Niraimathi, K L; Sudha, V; Lavanya, R; Brindha, P

2013-02-01

The present work focuses the use of the aqueous extract of Alternanthera sessilis Linn. (Amaranthaceae) in producing silver nanoparticles (AgNPs) from silver nitrate aqueous. Phytochemical analysis of the extract revealed the presence of alkaloid, tannins, ascorbic acid, carbohydrates and proteins and they serve as effective reducing and capping agents for converting silver nitrate into nanoparticles. The synthesized silver nanoparticles (AgNPs) were also tested for proteins and ascorbic acid. Its pH was also determined (5.63). The AgNPs obtained was characterized by UV-vis spectroscopy, FT-IR spectroscopy, SEM, Zeta sizer and TG-DSC. SEM images which revealed the presence of various shapes and sizes. FT-IR spectrum showed the AgNPs having a coating of proteins indicating a dual role of bio-molecules responsible for capping and efficient stabilization of the silver nanoparticles. Presence of impurities and melting point profile were screened by TG-DSC analyzer. AgNPs were synthesized from the silver nitrate through the reducing power of ascorbic acid present in A. sessilis leaves. In this study, we also investigated antimicrobial and antioxidant activity of green synthesized AgNPs. The antimicrobial activity is investigated by Bauer et al.'s method. Antioxidant activity was done by DPPH method. Copyright © 2012 Elsevier B.V. All rights reserved.

Effects of different cooking methods on nutritional and physicochemical characteristics of selected vegetables.

PubMed

Miglio, Cristiana; Chiavaro, Emma; Visconti, Attilio; Fogliano, Vincenzo; Pellegrini, Nicoletta

2008-01-09

The objective of the present study was to evaluate the effect of three common cooking practices (i.e., boiling, steaming, and frying) on phytochemical contents (i.e., polyphenols, carotenoids, glucosinolates, and ascorbic acid), total antioxidant capacities (TAC), as measured by three different analytical assays [Trolox equivalent antioxidant capacity (TEAC), total radical-trapping antioxidant parameter (TRAP), ferric reducing antioxidant power (FRAP)] and physicochemical parameters of three vegetables (carrots, courgettes, and broccoli). Water-cooking treatments better preserved the antioxidant compounds, particularly carotenoids, in all vegetables analyzed and ascorbic acid in carrots and courgettes. Steamed vegetables maintained a better texture quality than boiled ones, whereas boiled vegetables showed limited discoloration. Fried vegetables showed the lowest degree of softening, even though antioxidant compounds were less retained. An overall increase of TEAC, FRAP, and TRAP values was observed in all cooked vegetables, probably because of matrix softening and increased extractability of compounds, which could be partially converted into more antioxidant chemical species. Our findings defy the notion that processed vegetables offer lower nutritional quality and also suggest that for each vegetable a cooking method would be preferred to preserve the nutritional and physicochemical qualities.

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

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

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

2006-04-01

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

Synergistic, additive and antagonistic effects of fruit mixtures on total antioxidant capacities and bioactive compounds in tropical fruit juices.

PubMed

Pereira, Ana Carolina da Silva; Wurlitzer, Nedio Jair; Dionisio, Ana Paula; Lacerda Soares, Marcia Valéria; Rocha Bastos, Maria do Socorro; Elesbão Alves, Ricardo; Montenegro Brasil, Isabella

2015-06-01

The objective of this work was investigate the synergistic, additive and antagonistic effects of fruit mixtures on total antioxidant capacities and bioactive compounds in tropical fruit juices, and optimize its formulation by the response surface methodology based on the responses: total polyphenols (TP), total antioxidant capacity (TAC), ascorbic acid content and sensorial acceptance. Camu-camu, acerola and acai were the major factors that influenced the antioxidant potential of the juice; and the yellow mombin showed a positive effect on the acceptance of the tropical juice. It was observed an/antagonistic effect between acerola and camu-camu for the TAC response. The optimum formulation obtained was 20% acerola, 10% camu-camu, 10% yellow mombin, 10% cashew apple and 10% acai, which was responsible for a response of 155.46 mg.100 g(-1) of ascorbic acid, 103.01 mg of GAE.100 g-1 of TP, 10.27 µM Trolox g(-1) of TAC and approximately 6.1 of acceptance.

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

PubMed

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

2011-08-01

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

The effect of the germination temperature on the phytochemical content of broccoli and rocket sprouts.

PubMed

Ragusa, Lucia; Picchi, Valentina; Tribulato, Alessandro; Cavallaro, Chiara; Lo Scalzo, Roberto; Branca, Ferdinando

2017-06-01

This study investigates the effect of different germination temperatures (10, 20 and 30 °C) on the phytochemical content as well as reducing and antioxidant capacity of broccoli and rocket sprouts. In both seeds and sprouts, the total glucosinolates and ascorbic acid contents did not differ between vegetables, while broccoli exhibited exceptionally higher polyphenols and greater reducing and antioxidant capacity compared to rocket. In both species, an increase in germination temperature positively affected the glucosinolate content. Ascorbic acid increased during germination without a difference among the three tested temperatures. The phenol content in broccoli sprouts increased when they were grown at 30 °C, but the amount decreased at the highest temperatures in rocket. The reducing and antioxidant capacities increased with germination, and higher indexes were detected at 10 °C, particularly in rocket. Different germination temperatures differentiate the health-promoting phytochemical content and antioxidant properties in broccoli and rocket sprouts.

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

PubMed

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

2016-03-15

Bioactive compounds (ascorbic acid, total phenolics and total antioxidants) are important constituents of citrus fruit juice; however, information with regard to their concentrations and changes in relation to tree age and storage conditions is limited. 'Kinnow' (Citrus nobilis Lour × Citrus deliciosa Tenora) mandarin juice from fruit of three tree ages (6, 18 and 35 years old) and fruit sizes (large, medium and small) were examined for their bioactive compounds during 7 days under ambient storage conditions (20 ± 2 °C and 60-65% relative humidity (RH)) and during 60 days under cold storage (4 ± 1 °C and 75-80% RH) conditions. Under ambient conditions, a reduction in total phenolic concentrations (TPC) and in total antioxidant activity (TAA) was found for the juice from all tree ages and fruit sizes. Overall, fruit from 18-year-old trees had higher mean TPC (95.86 µg mL(-1) ) and TAA (93.68 mg L(-1) ), as compared to 6 and 35-year-old trees. Likewise, in cold storage, TAA decreased in all fruit size groups from 18 and 35-year-old trees. In all tree age and fruit size groups, TPC decreased initially during 15 days of cold storage and then increased gradually with increase in storage duration. Ascorbic acid concentrations showed an increasing trend in all fruit size groups from 35-year-old trees. Overall, during cold storage, fruit from 18-year-old trees maintained higher mean ascorbic acid (33.05 mg 100 mL(-1) ) concentrations, whereas fruit from 6-year-old trees had higher TAA (153.1 mg L(-1) ) and TPC (115.1 µg mL(-1) ). Large-sized fruit had higher ascorbic acid (32.08 mg 100 mL(-1) ) concentrations and TAA (157.5 mg L(-1) ). Fruit from 18-year-old trees maintained higher TPC and TAA under ambient storage conditions, whereas fruit from 6-year-old trees maintained higher TPC and TAA during cold storage. Small-sized fruit had higher TPC after ambient temperature storage, whereas large fruit size showed higher ascorbic acid concentrations and TAA after cold storage. © 2015 Society of Chemical Industry.

Effect of cultivation line and peeling on food composition, taste characteristic, aroma profile, and antioxidant activity of Shiikuwasha (Citrus depressa Hayata) juice.

PubMed

Asikin, Yonathan; Fukunaga, Hibiki; Yamano, Yoshimasa; Hou, De-Xing; Maeda, Goki; Wada, Koji

2014-09-01

Shiikuwasha (Citrus depressa Hayata) juice from four main cultivation lines subjected to two peeling practices (with or without peeling) were discriminated in terms of quality attributes, represented by sugar and organic acid composition, taste characteristic, aroma profile, and antioxidant activity. Shiikuwasha juice from these lines had diverse food compositions; 'Izumi kugani' juice had lower acidity but contained more ascorbic acid than that of other cultivation lines. The composition of volatile aroma components was influenced by fruit cultivation line, whereas its content was affected by peeling process (20.26-53.73 mg L(-1) in whole juice versus 0.82-1.58 mg L(-1) in flesh juice). Peeling also caused Shiikuwasha juice to be less astringent and acidic bitter and to lose its antioxidant activity. Moreover, the total phenolic and ascorbic acid content of Shiikuwasha juice positively influenced its antioxidant activity. Each fruit cultivation line had a distinct food composition, taste characteristic, and aroma profile. Peeling in Shiikuwasha juice production might reduce aftertaste, and thus might improve its palatability. Comprehensive information on the effect of cultivation line and peeling on quality attributes will be useful for Shiikuwasha juice production, and can be applied to juice production of similar small citrus fruits. © 2014 Society of Chemical Industry.

Analytical traceability of melon (Cucumis melo var reticulatus): proximate composition, bioactive compounds, and antioxidant capacity in relation to cultivar, plant physiology state, and seasonal variability.

PubMed

Maietti, Annalisa; Tedeschi, Paola; Stagno, Caterina; Bordiga, Matteo; Travaglia, Fabiano; Locatelli, Monica; Arlorio, Marco; Brandolini, Vincenzo

2012-06-01

Two morphologically different cultivars of Italian melons (Baggio and Giusto) were characterized considering samples harvested in different times, at the beginning (BPP) and at the end of the physiological plant production period (EPP). Proximate composition, protein, minerals, pH, phenolic content, antioxidant capacity, ascorbic acid, carotenoids, condensed tannins, and flavonoids were measured, showing a significant decrease in EPP samples (phenolics, antioxidant capacity, condensed tannins, and flavonoids); ascorbic acid decreased in Giusto cv, carotenoids in Baggio cv. Mineral content increased in either the cultivars (EPP samples). Year-to-year difference was significantly highlighted; the plant growing cycle significantly affected the chemotype. Despite these effects, the Principal Component Analysis (PCA) permitted the discrimination of Baggio from Giusto cv, and the discrimination of BPP from EPP samples as well. © 2012 Institute of Food Technologists®

Effect of brewing conditions on antioxidant properties of rosehip tea beverage: study by response surface methodology.

PubMed

İlyasoğlu, Huri; Arpa, Tuba Eda

2017-10-01

The aim of this study was to investigate the effects of brewing conditions (infusion time and temperature) on the antioxidant properties of rosehip tea beverage. The ascorbic acid content, total phenolic content (TPC), and ferric reducing antioxidant power (FRAP) of rosehip tea beverage were analysed. A two-factor and three-level central composite design was applied to evaluate the effects of the variables on the responses. The best quadratic models were obtained for all responses. The generated models were validated under the optimal conditions. At the optimal conditions, the rosehip tea beverage had 3.15 mg 100 mL -1 of ascorbic acid, 61.44 mg 100 mL -1 of TPC, and 2591 µmol of FRAP. The best brewing conditions for the rosehip tea beverage were found to be an infusion time of 6-8 min at temperatures of 84-86 °C.

Oxidant and antioxidant status in children with subacute sclerosing panencephalitis.

PubMed

Caksen, Hüseyin; Ozkan, Mustafa; Cemek, Mustafa; Cemek, Fatma

2014-11-01

We analyzed serum alpha-tocopherol, beta-carotene, retinol, and ascorbic acid levels and malondialdehyde and reduced glutathione concentrations on erythrocyte and cerebrospinal fluid in 30 patients with subacute sclerosing panencephalitis to evaluate oxidant and antioxidant status. Serum alpha-tocopherol, beta-carotene, retinol, ascorbic acid levels, and erythrocyte and cerebrospinal fluid reduced glutathione concentrations were decreased; however, erythrocyte and cerebrospinal fluid malondialdehyde levels were increased in the patients. Cerebrospinal fluid malondialdehyde levels were different between clinical stages of the disease (P < .05). Higher cerebrospinal fluid malondialdehyde level was associated with the more severe clinical stage. A positive correlation was found between cerebrospinal fluid malondialdehyde level and clinical stages (r = 0.42; P < .05) and between erythrocyte malondialdehyde level and clinical stages (r = 0.40; P < .05). Our findings showed presence of oxidative damage in subacute sclerosing panencephalitis and that antioxidants were increased as defense mechanisms of the organism against oxidative damage. © The Author(s) 2013.

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

PubMed

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

2012-06-28

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

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

PubMed

Chikvaidze, Eduard; Topeshashvili, Maia

2015-12-01

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

Changes in element accumulation, phenolic metabolism, and antioxidative enzyme activities in the red-skin roots of Panax ginseng.

PubMed

Zhou, Ying; Yang, Zhenming; Gao, Lingling; Liu, Wen; Liu, Rongkun; Zhao, Junting; You, Jiangfeng

2017-07-01

Red-skin root disease has seriously decreased the quality and production of Panax ginseng (ginseng). To explore the disease's origin, comparative analysis was performed in different parts of the plant, particularly the epidermis, cortex, and/or fibrous roots of 5-yr-old healthy and diseased red-skin ginseng. The inorganic element composition, phenolic compound concentration, reactive oxidation system, antioxidant concentrations such as ascorbate and glutathione, activities of enzymes related to phenolic metabolism and oxidation, and antioxidative system particularly the ascorbate-glutathione cycle were examined using conventional methods. Aluminum (Al), iron (Fe), magnesium, and phosphorus were increased, whereas manganese was unchanged and calcium was decreased in the epidermis and fibrous root of red-skin ginseng, which also contained higher levels of phenolic compounds, higher activities of the phenolic compound-synthesizing enzyme phenylalanine ammonia-lyase and the phenolic compound oxidation-related enzymes guaiacol peroxidase and polyphenoloxidase. As the substrate of guaiacol peroxidase, higher levels of H 2 O 2 and correspondingly higher activities of superoxide dismutase and catalase were found in red-skin ginseng. Increased levels of ascorbate and glutathione; increased activities of l-galactose 1-dehydrogenase, ascorbate peroxidase, ascorbic acid oxidase, and glutathione reductase; and lower activities of dehydroascorbate reductase, monodehydroascorbate reductase, and glutathione peroxidase were found in red-skin ginseng. Glutathione- S -transferase activity remained constant. Hence, higher element accumulation, particularly Al and Fe, activated multiple enzymes related to accumulation of phenolic compounds and their oxidation. This might contribute to red-skin symptoms in ginseng. It is proposed that antioxidant and antioxidative enzymes, especially those involved in ascorbate-glutathione cycles, are activated to protect against phenolic compound oxidation.

Post-Exposure Antioxidant Treatment in Rats Decreases Airway Hyperplasia and Hyperreactivity Due to Chlorine Inhalation

PubMed Central

Bracher, Andreas; Doran, Stephen F.; Squadrito, Giuseppe L.; Fernandez, Solana; Postlethwait, Edward M.; Bowen, Larry; Matalon, Sadis

2012-01-01

We assessed the safety and efficacy of combined intravenous and aerosolized antioxidant administration to attenuate chlorine gas–induced airway alterations when administered after exposure. Adult male Sprague-Dawley rats were exposed to air or 400 parts per million (ppm) chlorine (a concentration likely to be encountered in the vicinity of industrial accidents) in environmental chambers for 30 minutes, and returned to room air, and they then received a single intravenous injection of ascorbic acid and deferoxamine or saline. At 1 hour and 15 hours after chlorine exposure, the rats were treated with aerosolized ascorbate and deferoxamine or vehicle. Lung antioxidant profiles, plasma ascorbate concentrations, airway morphology, and airway reactivity were evaluated at 24 hours and 7 days after chlorine exposure. At 24 hours after exposure, chlorine-exposed rats had significantly lower pulmonary ascorbate and reduced glutathione concentrations. Treatment with antioxidants restored depleted ascorbate in lungs and plasma. At 7 days after exposure, in chlorine-exposed, vehicle-treated rats, the thickness of the proximal airways was 60% greater than in control rats, with twice the amount of mucosubstances. Airway resistance in response to methacholine challenge was also significantly elevated. Combined treatment with intravenous and aerosolized antioxidants restored airway morphology, the amount of airway mucosubstances, and airway reactivity to control levels by 7 days after chlorine exposure. Our results demonstrate for the first time, to the best of our knowledge, that severe injury to major airways in rats exposed to chlorine, as characterized by epithelial hyperplasia, mucus accumulation, and airway hyperreactivity, can be reversed in a safe and efficacious manner by the post-exposure administration of ascorbate and deferoxamine. PMID:22162906

Antioxidant action of ganghwayakssuk (Artemisia princeps Pamp.) in combination with ascorbic acid to increase the shelf life in raw and deep fried chicken nuggets.

PubMed

Hwang, Ko-Eun; Choi, Yun-Sang; Choi, Sun-Mi; Kim, Hyun-Wook; Choi, Ji-Hun; Lee, Mi-Ai; Kim, Cheon-Jei

2013-11-01

Raw and deep fried chicken nuggets containing various levels of ganghwayakssuk ethanolic extract (GE) in combination with ascorbic acid (Aa) were evaluated for shelf-life during refrigerated storage (4°C). The pH and color (lightness, redness, and yellowness) values of raw and deep fried samples were significantly affected by the addition of GE (P<0.05). All antioxidant combinations except for Aa+GE 0.01 were effective at delaying lipid oxidation (CD, POV, and TBARS) when compared to the control or Aa. Raw samples with GE 0.2 and Aa+GE 0.1 exhibited lower bacterial populations during storage. The sensory characteristics (color, juiciness, flavor, tenderness, and overall acceptability) did not differ significantly in all deep fried chicken nugget samples, except color, whereas storage time had a significant effect (P<0.05). The results suggest the possibility of utilizing raw and deep fried chicken nuggets with a mixture of ganghwayakssuk and ascorbic acid for the increase of shelf-life and quality. Copyright © 2013 Elsevier Ltd. All rights reserved.

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

USDA-ARS?s Scientific Manuscript database

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

Study of quinones reactions with wine nucleophiles by cyclic voltammetry.

PubMed

Oliveira, Carla M; Barros, António S; Ferreira, António C S; Silva, Artur M S

2016-11-15

Quinones are electrophilic species which can react with various nucleophiles, like wine antioxidants, such as sulfur dioxide or ascorbic acid, thiols, amino acids, and numerous polyphenols. These reactions are very important in wine aging because they mediate oxygen reactions during both production and bottle aging phases. In this work, the major challenge was to determine the interaction between ortho-quinones and wine nucleophiles (amino acids, thiols, and the antioxidants SO2 and ascorbic acid), by cyclic voltammetry. Wine-model solutions with gallic acid, caffeic acid, or (+)-catechin and nucleophilic compounds were used. To understand the effect of nucleophilic addition in wine, a white wine with the same added nucleophiles was also analysed. Cyclic voltammograms were taken with glassy carbon electrode or screen-printed carbon electrodes, respectively, for wine-model and white wines solutions, in the absence and in the presence of nucleophiles. A nucleophilic order profile related to the cathodic current intensity decrease was observed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Adaptogenic and nootropic activities of aqueous extract of Vitis vinifera (grape seed): an experimental study in rat model

PubMed Central

Sreemantula, Satyanarayana; Nammi, Srinivas; Kolanukonda, Rajabhanu; Koppula, Sushruta; Boini, Krishna M

2005-01-01

Background The aerial parts of Vitis vinifera (common grape or European grape) have been widely used in Ayurveda to treat a variety of common and stress related disorders. In the present investigation, the seed extract of V. vinifera was evaluated for antistress activity in normal and stress induced rats. Furthermore, the extract was studied for nootropic activity in rats and in-vitro antioxidant potential to correlate its antistress activity. Methods For the evaluation of antistress activity, groups of rats (n = 6) were subjected to forced swim stress one hour after daily treatment of V. vinifera extract. Urinary vanillylmandelic acid (VMA) and ascorbic acid were selected as non-invasive biomarkers to assess the antistress activity. The 24 h urinary excretion of vanillylmandelic acid (VMA) and ascorbic acid were determined by spectrophotometric methods in all groups under normal and stressed conditions. The nootropic activity of the extract as determined from acquisition, retention and retrieval in rats was studied by conditioned avoidance response using Cook's pole climbing apparatus. The in vitro antioxidant activity was determined based on the ability of V. vinifera to scavenge hydroxyl radicals. Results Daily administration of V. vinifera at doses of 100, 200 and 300 mg/kg body weight one hour prior to induction of stress inhibited the stress induced urinary biochemical changes in a dose dependent manner. However, no change in the urinary excretion of VMA and ascorbic acid was observed in normal animals at all the doses studied. The cognition, as determined by the acquisition, retention and recovery in rats was observed to be dose dependent. The extract also produced significant inhibition of hydroxyl radicals in comparison to ascorbic acid in a dose dependent manner. Conclusion The present study provides scientific support for the antistress (adaptogenic), antioxidant and nootropic activities of V. vinifera seed extract and substantiate the traditional claims for the usage of grape fruits and seeds in stress induced disorders. PMID:15656916

Physiological Concentrations of Ascorbate Cannot Prevent the Potentially Damaging Reactions of Protein Radicals in Humans.

PubMed

Nauser, Thomas; Gebicki, Janusz M

2017-09-18

The principal initial biological targets of free radicals formed under conditions of oxidative stress are the proteins. The most common products of the interaction are carbon-centered alkyl radicals which react rapidly with oxygen to form peroxyl radicals and hydroperoxides. All these species are reactive, capable of propagating the free radical damage to enzymes, nucleic acids, lipids, and endogenous antioxidants, leading finally to the pathologies associated with oxidative stress. The best chance of preventing this chain of damage is in early repair of the protein radicals by antioxidants. Estimate of the effectiveness of the physiologically significant antioxidants requires knowledge of the antioxidant tissue concentrations and rate constants of their reaction with protein radicals. Previous studies by pulse radiolysis have shown that only ascorbate can repair the Trp and Tyr protein radicals before they form peroxyl radicals under physiological concentrations of oxygen. We have now extended this work to other protein C-centered radicals generated by hydroxyl radicals because these and many other free radicals formed under oxidative stress can produce secondary radicals on virtually any amino acid residue. Pulse radiolysis identified two classes of rate constants for reactions of protein radicals with ascorbate, a faster one in the range (9-60) × 10 7 M -1 s -1 and a slow one with a range of (0.5-2) × 10 7 M -1 s -1 . These results show that ascorbate can prevent further reactions of protein radicals only in the few human tissues where its concentration exceeds about 2.5 mM.

New Electrochemical Evaluation of the Antioxidant Capacity of Beverages with Polyoxometalates as Redox Probes.

PubMed

Ueda, Tadaharu; Okumura, Takashi; Tanaka, Yukino; Akase, Saki; Shimamura, Tomoko; Ukeda, Hiroyuki

2016-01-01

A new method was developed to evaluate antioxidant activity based on the redox properties of polyoxometalates, which are partially reduced by antioxidants to generate a limiting potential. The polyoxometalates [PMo12O40](3-), [PVW11O40](4-) and [SV2W10O40]4- formed in situ were used as electrochemical probes for the new evaluation method, and their formation conditions were optimized to evaluate the antioxidant activities of gallic acid, ellagic acid, catechin, quercetin, morin, trans-ferulic acid, sesamol, α-tocopherol, δ-tocopherol and L-ascorbic acid. The observed difference between initial potential and limiting potential (ΔE) were compared with spectrophotometrically evaluated antioxidant activities. In addition, the antioxidant capacities of five beverages (Japanese green tea, concentrated catechin-containing green tea, grapefruit juice, red wine and Japanese sake) were evaluated.

Trichoderma harzianum T-78 supplementation of compost stimulates the antioxidant defence system in melon plants.

PubMed

Bernal-Vicente, Agustina; Pascual, José A; Tittarelli, Fabio; Hernández, José A; Diaz-Vivancos, Pedro

2015-08-30

Compost is emerging as an alternative plant growing medium in efforts to achieve more sustainable agriculture. The addition of specific microorganisms such as Trichoderma harzianum to plant growth substrates increases yields and reduces plant diseases, but the mechanisms of such biostimulants and the biocontrol effects are not yet fully understood. In this work we investigated how the addition of citrus and vineyard composts, either alone or in combination with T. harzianum T-78, affects the antioxidant defence system in melon plants under nursery conditions. Compost application and/or Trichoderma inoculation modulated the antioxidant defence system in melon plants. The combination of citrus compost and Trichoderma showed a biostimulant effect that correlated with an increase in ascorbate recycling enzymes (monodehydroascorbate reductase, dehydroascorbate reductase) and peroxidase. Moreover, the inoculation of both composts with Trichoderma increased the activity of antioxidant enzymes, especially those involved in ascorbate recycling. Based on the long-established relationship between ascorbic acid and plant defence responses as well as plant growth and development, it can be suggested that ascorbate recycling activities play a major role in the protection provided by Trichoderma and its biostimulant effect and that these outcomes are linked to increases in antioxidant enzymes. We can conclude that the combination of citrus compost and T. harzianum T-78 constitutes a viable, environmentally friendly strategy for improving melon plant production. © 2014 Society of Chemical Industry.

Minimization of free radical damage by metal catalysis of multivitamin/multimineral supplements

PubMed Central

2010-01-01

Multivitamin/multimineral complexes are the most common dietary supplements. Unlike minerals in foods that are incorporated in bioorganic structures, minerals in dietary supplements are typically in an inorganic form. These minerals can catalyze the generation of free radicals, thereby oxidizing antioxidants during digestion. Here we examine the ability of a matrix consisting of an amino acid and non-digestible oligosaccharide (AAOS) to blunt metal-catalyzed oxidations. Monitoring of ascorbate radical generated by copper shows that ascorbate is oxidized more slowly with the AAOS matrix than with copper sulfate. Measurement of the rate of oxidation of ascorbic acid and Trolox® by catalytic metals confirmed the ability of AAOS to slow these oxidations. Similar results were observed with iron-catalyzed formation of hydroxyl radicals. When compared to traditional forms of minerals used in supplements, we conclude that the oxidative loss of antioxidants in solution at physiological pH is much slower when AAOS is present. PMID:21092298

Effect of calcium and salicylic acid on quality retention in relation to antioxidative enzymes in radish stored under refrigerated conditions.

PubMed

Devi, Jomika; Bhatia, Surekha; Alam, M S; Dhillon, Tarsem Singh

2018-03-01

Effect of post harvest treatments with calcium chloride (CaCl 2 ) and salicylic acid (SA) on physiological and biochemical parameters in relation to activities of antioxidative enzymes were investigated in radish. Radish of variety Punjab Safed Mooli 2 was harvested, washed and treated with CaCl 2 (1, 1.5 and 2%) or SA (1, 1.5 and 2 mM). Treated as well as untreated radish were placed in open trays and stored under refrigerated (5 ± 1 °C, 90% RH) conditions for 42 days. Treatment of radish with CaCl 2 and SA slowed down changes in physiological weight, colour, total soluble solids, ascorbic acid, titrable acidity, total phenolics and antioxidant activity. Treated samples exhibited higher enhancement in activities of antioxidant enzymes viz. catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), peroxidase (POD), dehydroascorbate reductase (DHAR) and monodehydro-ascorbate reductase (MDHAR) than untreated samples. However SA was found to be more effective in slowing down the metabolic activities of radish as compared to CaCl 2 treatment. Among all the treatments, 1.5 mM SA maintained the quality parameters to greater extent probably by reducing the oxidative stress to larger extent due to highest activities of antioxidative enzymes and can be used to enhance the shelf life of radish during refrigerated storage.

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

PubMed

Oboh, G; Akindahunsi, A A

2004-01-01

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

Metabolic Pathways Regulated by Chitosan Contributing to Drought Resistance in White Clover.

PubMed

Li, Zhou; Zhang, Yan; Zhang, Xinquan; Merewitz, Emily; Peng, Yan; Ma, Xiao; Huang, Linkai; Yan, Yanhong

2017-08-04

Increased endogenous chitosan (CTS) could be associated with improved drought resistance in white clover (Trifolium repens). Plants were pretreated with or without 1 mg/mL CTS and then were subjected to optimal or water-limited condition in controlled growth chambers for 6 days. Phenotypic and physiological results indicated that exogenous CTS significantly improved drought resistance of white clover. Metabolome results showed that exogenous CTS induced a significant increase in endogenous CTS content during dehydration accompanied by the maintenance of greater accumulation of sugars, sugar alcohols, amino acids, organic acids, and other metabolites (ascorbate, glutathione, flavonoids, putrescine, and spermidine). These compounds are associated with osmotic adjustment, antioxidant defense, stress signaling, and energy metabolism under stress condition. Similarly, transcriptome revealed that many genes in relation to amino acid and carbohydrate metabolism, energy production and conversion, and ascorbate-glutathione and flavonoid metabolism were significantly up-regulated by CTS in response to dehydration stress. CTS-induced drought resistance was associated with the accumulation of stress protective metabolites, the enhancement of ascorbate-glutathione and tricarboxylic acid cycle, and increases in the γ-aminobutyric acid shunt, polyamine synthesis, and flavonoids metabolism contributing to improved osmotic adjustment, antioxidant capacity, stress signaling, and energy production for stress defense, thereby maintaining metabolic homeostasis under dehydration stress.

Measurement of Antioxidant Capacity by Electron Spin Resonance Spectroscopy Based on Copper(II) Reduction.

PubMed

Li, Dan; Jiang, Jia; Han, Dandan; Yu, Xinyu; Wang, Kun; Zang, Shuang; Lu, Dayong; Yu, Aimin; Zhang, Ziwei

2016-04-05

A new method is proposed for measuring the antioxidant capacity by electron spin resonance spectroscopy based on the loss of electron spin resonance signal after Cu(2+) is reduced to Cu(+) with antioxidant. Cu(+) was removed by precipitation in the presence of SCN(-). The remaining Cu(2+) was coordinated with diethyldithiocarbamate, extracted into n-butanol and determined by electron spin resonance spectrometry. Eight standards widely used in antioxidant capacity determination, including Trolox, ascorbic acid, ferulic acid, rutin, caffeic acid, quercetin, chlorogenic acid, and gallic acid were investigated. The standard curves for determining the eight standards were plotted, and results showed that the linear regression correlation coefficients were all high enough (r > 0.99). Trolox equivalent antioxidant capacity values for the antioxidant standards were calculated, and a good correlation (r > 0.94) between the values obtained by the present method and cupric reducing antioxidant capacity method was observed. The present method was applied to the analysis of real fruit samples and the evaluation of the antioxidant capacity of these fruits.

Role of cellular antioxidants (glutathione and ascorbic acid) in the growth and development of wild carrot suspension cultures

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

Earnshaw, B.A.

1986-01-01

Determinations of endogenous glutathione (GSH), glutathione disulfide (GSSG), ascorbic acid (AA) and dehydroascorbic acid (DHA) in proliferating and developing wild carrot cultures showed that lower levels of GSH and AA were associated with developing cultures. The GSSG and DHA levels did not account for the changes in the levels of antioxidants between proliferating and developing cultures. Studies were designed to test an observed auxin (2,4-Dichlorophenoxyacetic acid, 2,4-D)-antioxidant association. Two fractions (embryo and less developed) were obtained by screening developed cultures which were previously grown in the presence of /sup 14/C-2, 4-D. The embryo fraction had a lower concentration of /supmore » 14/C than the less developed fraction, supporting the association, since the two fractions showed this relationship with respect to GSH and AA concentrations. Determinations of GSH and AA levels of cells grown in various concentrations of 2,4-D showed the association, decreases in the 2,4-D concentration correlated with decreases in the GSH and AA concentrations. The existence of a respiratory pathway involving GSSG reductase, DHA reductase, and AA oxidase was investigated to test whether inhibition of AA oxidase by 2,4-D could explain the auxin-antioxidant association; however, AA oxidase activity was not detected.« less

Studies on chemical constituents and bioactivity of Rosa micrantha: an alternative antioxidants source for food, pharmaceutical, or cosmetic applications.

PubMed

Guimarães, Rafaela; Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C F R

2010-05-26

Rose species have long been used for food and medicinal purposes. Rosa micrantha is one of the rose species that grow feral in the northeastern Portuguese region so-called Nordeste Transmontano. For the first time, chemical composition and bioactivity of their petals, fertilized flowers, unripe, ripening, and overripe hips were evaluated in order to valorize them as sources of important phytochemicals. Chemical characterization included determination of proteins, fats, ash, and carbohydrates, particularly sugars, by HPLC-RI, fatty acids by GC-FID, tocopherols by HPLC-fluorescence, and phenolics, flavonoids, carotenoids, and ascorbic acid by spectrophotometric techniques. Bioactivity was evaluated through screening of antioxidant properties: radical scavenging effects, reducing power, and inhibition of lipid peroxidation. Ripening and overripe hips showed high nutritional value including proteins, carbohydrates, omega-3 and omega-6 fatty acids, energy, sugars, particularly the reducing sugars fructose and glucose, and ascorbic acid (>693 mg/100 g). Fertilized flowers and petals revealed the highest antioxidant activity (EC(50) > 152 microg/mL) and phenolics, flavonoids, and tocopherols contents (>35 mg/100 g). Furthermore, petals, ripening, and overripe hips are important sources of carotenoid pigments (>64 mg/100 g). Because of the diversity and abundance of antioxidants found in this species, some food, cosmetic, and pharmaceutical applications could be explored.

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

PubMed

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

2011-12-27

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

Alterations in antioxidant defense system of workers chronically exposed to arsenic, cadmium and mercury from coal flying ash.

PubMed

Zeneli, Lulzim; Sekovanić, Ankica; Ajvazi, Majlinda; Kurti, Leonard; Daci, Nexhat

2016-02-01

Humans are exposed to different stress factors that are responsible for over-production of reactive oxygen species. Exposure to heavy metals is one of these factors. The aim of the study was to analyze the effect of chronic exposure to heavy metals through coal flying ash on the efficiency of antioxidative defensive mechanisms, represented by the activity of superoxide dismutase, glutathione peroxidase and ascorbic acid. Nonessential elements such as arsenic and mercury levels showed a significant increase (p > 0.001) in the power plant workers rather than in the control subjects. There were no significant differences of blood cadmium between power plant workers and control subjects. We found a significant positive correlation (p < 0.05) between BAs/SZn (r = 0.211), BAs/BSe (r = 0.287), BCd/SCu (r = 0.32) and BHg/BSe (r = 0.263) in the plant workers. Red blood cell antioxidant enzymes and plasma ascorbic acid were significantly lower in power plants workers than in the control group (p < 0.002). We can conclude that levels of mercury, arsenic and cadmium in blood, despite their concentration within the reference values, significantly affect plasma ascorbic acid concentration, superoxide dismutase and glutathione peroxidase activity, which are able to increase the risk of oxidative stress.

Oxidants, antioxidants, and respiratory tract lining fluids.

PubMed Central

Cross, C E; van der Vliet, A; O'Neill, C A; Louie, S; Halliwell, B

1994-01-01

Respiratory tract lining fluids (RTLFs) are a heterogeneous group of substances covering the respiratory tract epithelial cells (RTECs) from nasal mucosa to alveoli. Antioxidant contained in the RTLFs can be expected to provide an initial defense against inhaled environmental toxins. The major antioxidants in RTLF include mucin, uric acid, protein (largely albumin), ascorbic acid, and reduced glutathione (GSH). RTLF antioxidants can be augmented by such processes as transudation/exudation of plasma constituents; RTEC secretory processes, including glandular mucus secretion; and cellular antioxidants derived from lysis of RTECs and of inflammatory cells. The antioxidant composition of RTLFs and their role in modulating normal and pathophysiologic RTEC functions under conditions of oxidative stress are yet to be fully characterized. PMID:7705296

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

PubMed

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

2000-05-01

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

Biochemical changes in grape rootstocks resulted from humic acid treatments in relation to nematode infection.

PubMed

Kesba, Hosny H; El-Beltagi, Hossam S

2012-04-01

To investigate the effect of humic acid on nematode infected, resistant and susceptible grapes in relation to lipid peroxidation and antioxidant mechanisms on selected biochemical parameters known as proactive substances. The grape rootstocks, superior, superior/freedom and freedom were reacted differently to Meloidogyne incognita and Rotylenchulus reniformis according to rootstock progenitor. Two weeks after inoculation, two commercial products of humic acid were applied at the rate of (2, 4 mL or grams/plant) as soil drench. After 4 months, nematode soil populations were extracted and counted. A subsample of roots from each plant was stained and gall numbers, embedded stages per root were calculated, final population, nematode build up (Pf/Pi), average of eggs/eggmass were estimated. Subsamples of fresh root of each treatment were chemically analyzed. Freedom reduced significantly the nematode criteria and build up. Humic acid granules appeared to be more suppressive to nematode build up on superior and the higher dose on superior/freedom than liquid treatments. On freedom, all treatments reduced significantly the nematode build up regardless to the material nature. The higher dose was more effective than the lower one. As a result of humic acid applications, the malondialdehyde (MDA) and H2O2 contents were significantly reduced after humic acid treatments while the antioxidant compounds glutathione (GSH), ascorbic acid (ASA) and total phenol contents were significantly increased when compared with check. Antioxidant defense enzymes ascorbate peroxidase (APX), superoxide dismutase (SOD), catalase (CAT) and polyphenol oxidase (PPO)showed significant increase in their specific activities in treated plants compared with nematode treated check. Humic acid treatments improve the yield of grape by increasing the contents of antioxidant compounds and the specific activities of antioxidant enzymes.

Biochemical changes in grape rootstocks resulted from humic acid treatments in relation to nematode infection

PubMed Central

Kesba, Hosny H; El-Beltagi, Hossam S

2012-01-01

Objective To investigate the effect of humic acid on nematode infected, resistant and susceptible grapes in relation to lipid peroxidation and antioxidant mechanisms on selected biochemical parameters known as proactive substances. Methods The grape rootstocks, superior, superior/freedom and freedom were reacted differently to Meloidogyne incognita and Rotylenchulus reniformis according to rootstock progenitor. Two weeks after inoculation, two commercial products of humic acid were applied at the rate of (2, 4 mL or grams/plant) as soil drench. After 4 months, nematode soil populations were extracted and counted. A subsample of roots from each plant was stained and gall numbers, embedded stages per root were calculated, final population, nematode build up (Pf/Pi), average of eggs/eggmass were estimated. Subsamples of fresh root of each treatment were chemically analyzed. Results Freedom reduced significantly the nematode criteria and build up. Humic acid granules appeared to be more suppressive to nematode build up on superior and the higher dose on superior/freedom than liquid treatments. On freedom, all treatments reduced significantly the nematode build up regardless to the material nature. The higher dose was more effective than the lower one. As a result of humic acid applications, the malondialdehyde (MDA) and H2O2 contents were significantly reduced after humic acid treatments while the antioxidant compounds glutathione (GSH), ascorbic acid (ASA) and total phenol contents were significantly increased when compared with check. Antioxidant defense enzymes ascorbate peroxidase (APX), superoxide dismutase (SOD), catalase (CAT) and polyphenol oxidase (PPO)showed significant increase in their specific activities in treated plants compared with nematode treated check. Conclusions Humic acid treatments improve the yield of grape by increasing the contents of antioxidant compounds and the specific activities of antioxidant enzymes. PMID:23569915

Assay dilution factors confound measures of total antioxidant capacity in polyphenol-rich juices

USDA-ARS?s Scientific Manuscript database

The extent to which sample dilution factor (DF) affects Total Antioxidant Capacity (TAC) values is poorly understood. Thus, we examined the impact of DF on the ORAC, FRAP, DPPH, and Total Phenols (TP) assays using pomegranate juice (PJ), grape juice (GJ), selected flavonoids, ascorbic acid, and ella...

Quality preservation of reduced sodium pork patties: effects of antioxidants on colour and lipid stability.

PubMed

Cheng, Jen-Hua; Wang, Shu-Tai; Ockerman, Herbert W

2013-09-01

The purpose of this study was to explore the effect of lipid oxidation and colour change of precooked pork patties with reduced sodium and added antioxidants. This study can fill the gap of antioxidant application between meat products with regular and low salt content. For precooked pork patties, addition of sodium tripolyphosphate and carnosine increased pH values and cooking yields. Patties with ascorbic acid had significantly higher a* values compared to the other samples. There was no significant difference of b* values among treatments. Precooked pork patties with sodium tripolyphosphate or carnosine had significantly higher L* values compared to other patties. The addition of antioxidants reduced lipid oxidation in precooked pork patties during refrigerated storage, except for the addition of 0.5% carnosine. Tripolyphosphate and ascorbic acid were successfully proven to be effective in retarding lipid oxidation and preserve the colour stability in reduced salt pork patties. This study provides a preliminary foundation of keeping meat products from lipid oxidation and maintaining in better stability. © 2013 Society of Chemical Industry.

Evaluation of the antioxidant effect of ganghwayakssuk (Artemisia princeps Pamp.) extract alone and in combination with ascorbic acid in raw chicken patties.

PubMed

Hwang, K E; Kim, H W; Choi, Y S; Lee, S Y; Yeo, E J; Ham, Y K; Choi, S M; Lee, M A; Kim, C J

2013-12-01

We investigated the inhibition of lipid oxidation of raw chicken patties by the antioxidants ascorbic acid (Aa), ganghwayakssuk extracts (GE), and their combination (Aa + GE). All antioxidant combinations were effective at delaying lipid oxidation compared with the control or Aa. A combination of Aa + GE (0.05% Aa + 0.2% GE) was the most effective for delaying lipid oxidation (TBA reactive substances, conjugated dienes, and peroxide formation). The color values of all samples were significantly affected by adding GE. Additionally, the redness, color difference, and hue values of all treatments, except for Aa, were lower than those of the control as the amount of GE increased. The total viable bacterial counts of samples with GE 0.2 and Aa + GE 0.2 were significantly affected during storage (P < 0.05). The results suggest that adding an antioxidant combination reduced the oxidative stress and microbial growth of raw chicken patties stored for 12 d under normal refrigeration temperature, which may extend the shelf life of chicken patties.

Multi-approach metabolomics analysis and artificial simplified phytocomplexes reveal cultivar-dependent synergy between polyphenols and ascorbic acid in fruits of the sweet cherry (Prunus avium L.)

PubMed Central

Di Carlo, Flavia; Poletti, Stefania; Bulgarini, Alessandra; Munari, Francesca; Negri, Stefano; Stocchero, Matteo; Ceoldo, Stefania; Avesani, Linda; Assfalg, Michael; Zoccatelli, Gianni; Guzzo, Flavia

2017-01-01

Fruits of the sweet cherry (Prunus avium L.) accumulate a range of antioxidants that can help to prevent cardiovascular disease, inflammation and cancer. We tested the in vitro antioxidant activity of 18 sweet cherry cultivars collected from 12 farms in the protected geographical indication region of Marostica (Vicenza, Italy) during two growing seasons. Multiple targeted and untargeted metabolomics approaches (NMR, LC-MS, HPLC-DAD, HPLC-UV) as well as artificial simplified phytocomplexes representing the cultivars Sandra Tardiva, Sandra and Grace Star were then used to determine whether the total antioxidant activity reflected the additive effects of each compound or resulted from synergistic interactions. We found that the composition of each cultivar depended more on genetic variability than environmental factors. Furthermore, phenolic compounds were the principal source of antioxidant activity and experiments with artificial simplified phytocomplexes indicated strong synergy between the anthocyanins and quercetins/ascorbic acid specifically in the cultivar Sandra Tardiva. Our data therefore indicate that the total antioxidant activity of sweet cherry fruits may originate from cultivar-dependent interactions among different classes of metabolite. PMID:28732012

Changes in antioxidant and biochemical activities in castor oil-coated Capsicum annuum L. during postharvest storage.

PubMed

Panigrahi, Jitendriya; Patel, Mansi; Patel, Niyati; Gheewala, Bhumi; Gantait, Saikat

2018-06-01

This study, for the first time, evaluates the efficiency of castor oil when used as an external coating on Capsicum annuum L., to increase postharvest storage-life at 4 ± 1 °C. The castor oil-coated fruits were successfully stored for 36 days, while the non-coated fruits could only sustain for 18 days. Throughout the storage period (at 9-day intervals), different antioxidants and biochemical assays (allied with storage) such as titratable acidity, ascorbic acid content, ferrous ion chelating activity, reducing power, DPPH scavenging activity, hydroxyl radical scavenging activity, total phenolic content, total sugar estimation, and enzymatic study of polyphenol oxidase and pectate lyase, were assessed. During storage, the castor oil-coated fruits showed a substantial decrease in titratable acidity, ascorbic acid content, total phenolic content, including antioxidant activities such as reducing power and DPPH activity; however, an increase in ferrous ion chelating activity, total soluble sugar content, polyphenol oxidase activity and initial pectate lyase activity was observed, in contrast to that of the non-coated fruits. The application of castor oil proved to be effective in delaying the ripening process of fruits during storage.

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

PubMed

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

2018-03-01

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

Effects of heat, pH, antioxidant, agitation and light on betacyanin stability using red-fleshed dragon fruit (Hylocereus polyrhizus) juice and concentrate as models.

PubMed

Wong, Yen-Ming; Siow, Lee-Fong

2015-05-01

Red-fleshed dragon fruit (Hylocereus polyrhizus) is rich in antioxidants. The aim of this study was to determine the effects of heat pasteurization, pH adjustment, ascorbic acid addition as well as storage under agitation and light or dark condition on betacyanin content in red-fleshed dragon fruit (Hylocereus polyrhizus) juice and concentrate. The concentrate was produced by concentrating clarified red-fleshed dragon fruit juice in a rotary evaporator at 40 °C. UV-Visible spectrophotometer was used for analyzing betacyanin content. Addition of 0.25 % ascorbic acid, pH 4.0, and pasteurization at 65 °C for 30 min were selected as the best processing conditions to retain betacyanin content in red-fleshed dragon fruit juice. Storage at the agitation speed of 220 rpm showed that the concentrated samples had higher betacyanin stability compared to juice, while both juice and concentrate had almost similar betacyanin stability when tested for storage in the presence of light. In summary, ascorbic acid stabilized betacyanin in both juice and concentrate at agitated or non-agitated conditions. In contrast, light degraded betacyanin in both juice and concentrate models.

Protective effect of ascorbic acid on netilmicin-induced lipid profile and peroxidation parameters in rabbit blood plasma.

PubMed

Devbhuti, Pritesh; Sikdar, Debasis; Saha, Achintya; Sengupta, Chandana

2011-01-01

A drug may cause alteration in blood-lipid profile and induce lipid peroxidation phenomena on administration in the body. Antioxidant may play beneficial role to control the negative alteration in lipid profile and lipid peroxidation. In view of this context, the present in vivo study was carried out to evaluate the role of ascorbic acid as antioxidant on netilmicin-induced alteration of blood lipid profile and peroxidation parameters. Rabbits were used as experimental animals and blood was collected to estimate blood-lipid profiles, such as total cholesterol (TCh), high density lipoprotein cholesterol (HDL-Ch), low density lipoprotein cholesterol (LDL-Ch), very low density lipoprotein cholesterol (VLDL-Ch), triglycerides (Tg), phospholipids (PL), and total lipids (TL), as well as peroxidation parameters, such as malondialdehyde (MDA), 4-hydroxy-2-nonenal (HNE), reduced glutathione (GSH) and nitric oxide (NO). The results revealed that netilmicin caused significant enhancement of MDA, HNE, TCh, LDL-Ch, VLDL-Ch, Tg levels and reduction in GSH, NO, HDL-Ch, PL, TL levels. On co-administration, ascorbic acid was found to be effective in reducing netilmicin-induced negative alterations of the above parameters.

Characterization of the antioxidant properties of hydrophilic and lipophilic extracts of Jute (Corchorus olitorius) leaf.

PubMed

Oboh, G; Raddatz, H; Henle, T

2009-01-01

Corchorus olitorius (jute) is a native plant of tropical Africa and Asia, and has since spread to Australia, South America and some parts of Europe. Its leafy vegetable is popularly used in soup preparation and folk medicine for the treatment of fever, chronic cystitis, cold and tumours. A comparative study of the antioxidant properties of hydrophilic extract (HE) and lipophilic extract (LE) constituents of the leafy vegetable has been assessed. HE and LE of the leaf were prepared using water and hexane, respectively and their antioxidant properties were determined. HE had a significantly higher (P<0.05) 1,1-diphenyl-2-picrylhydrazyl radical-scavenging ability (aqueous, 9.6-84.4%; hexane, 2.0-20.4%), reducing power (aqueous, 0.67 mmol ascorbic acid equivalent/g; hexane, 0.49 mmol ascorbic acid equivalent/g) and trolox equivalent antioxidant capacity (aqueous, 2.3 mmol/g; hexane, 1.1 mmol/g) than LE; conversely, LE had a significantly higher (P<0.05) OH. scavenging activity (44.5-46.2%) than HE (11.6-32.3%), while there was no significant difference (P>0.05) in their Fe(II) chelating ability (HE, 57.7-66.7%; LE, 56.4-61.1%). The higher 1,1-diphenyl-2-picrylhydrazyl radical-scavenging ability, reducing power and trolox equivalent antioxidant capacity of the hydrophilic extract may be due to its significantly higher (P<0.05) total phenol (630.8 mg/100 g), total flavonoid (227.8 mg/100 g) and non-flavonoid polyphenols (403.0 mg/100 g), and its high ascorbic acid content (32.6 mg/100 g). While the higher OH. scavenging ability of LE may be due to its high total carotenoid content (42.5 mg/100 g). Therefore, the additive/synergistic antioxidant activities of the hydrophilic and lipophilic constituents may contribute to the medicinal properties of C. olitorius leaf.

Assay Dilution Factors Confound Measures of Total Antioxidant Capacity in Polyphenol-Rich Juices

PubMed Central

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

2016-01-01

The extent to which sample dilution factor (DF) affects total antioxidant capacity (TAC) values is poorly understood. Thus, we examined the impact of DF on the ORAC, FRAP, DPPH, and total phenols (TP) assays using pomegranate juice (PJ), grape juice (GJ), selected flavonoids, ascorbic acid, and ellagic acid. For ORAC, GJ was comparable to PJ at DF 750, but at DF 2000, the ORAC value of GJ was 40% more than PJ. Increasing DF increased GJ and PJ, DPPH, TP, and FRAP values 11% and 14%, respectively. Increased test concentrations of quercetin and catechin resulted in 51% and 126% greater ORAC values, but decreased naringenin by 68%. Flavonoids, but not ellagic acid or ascorbic acid, may contribute to the dilution effect on the variation of final TAC values. Thus, reporting TAC or TP using a single DF may introduce uncertainty about the confidence of TAC assay values, especially when comparing different juices. These results underscore the importance of using compatible test standards for reporting TAC values. PMID:22251245

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

PubMed Central

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

2013-01-01

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

Mitochondria, Energy and Cancer: The Relationship with Ascorbic Acid

PubMed Central

González, Michael J.; Rosario-Pérez, Glorivee; Guzmán, Angélica M.; Miranda-Massari, Jorge R.; Duconge, Jorge; Lavergne, Julio; Fernandez, Nadia; Ortiz, Norma; Quintero, Ana; Mikirova, Nina; Riordan, Neil H.; Ricart, Carlos M.

2012-01-01

Ascorbic Acid (AA) has been used in the prevention and treatment of cancer with reported effectiveness. Mitochondria may be one of the principal targets of ascorbate's cellular activity and it may play an important role in the development and progression of cancer. Mitochondria, besides generating adenosine triphosphate (ATP), has a role in apoptosis regulation and in the production of regulatory oxidative species that may be relevant in gene expression. At higher concentrations AA may increase ATP production by increasing mitochondrial electron flux, also may induce apoptotic cell death in tumor cell lines, probably via its pro-oxidant action In contrast, at lower concentrations AA displays antioxidant properties that may prevent the activation of oxidant-induced apoptosis. These concentration dependent activities of ascorbate may explain in part the seemingly contradictory results that have been reported previously. PMID:23565030

Influence of putrescine and carnauba wax on functional and sensory quality of pomegranate (Punica granatum L.) fruits during storage.

PubMed

Barman, Kalyan; Asrey, Ram; Pal, R K; Kaur, Charanjit; Jha, S K

2014-01-01

Functional properties (anthocyanins, antioxidant, ascorbic acid and tannin) and sensory score were determined in pomegranate fruits at two storage temperatures (3 and 5 °C) after treatment with 2 mM putrescine and 1 : 10 carnauba wax (carnauba wax : water). The treatments (putrescine and carnauba wax) were given by immersion method followed by storage up to 60 days. Both treatments retained significantly higher anthocyanins, antioxidant, ascorbic acid, tannin and sensory qualities as compared with control fruits under both the storage conditions. Combined application of putrescine + carnauba wax showed better response in retaining functional properties than putrescine treated or nontreated fruits. The impacts of putrescine and carnauba wax treatments were found more pronounced after 30 days at 3-5 °C storage temperature in retaining functional and sensory qualities. After 60 days of storage, putrescine + carnauba wax retained about 25% higher antioxidant activity both at 3 and 5 °C storage temperatures.

A study of extraction process and in vitro antioxidant activity of total phenols from Rhizoma Imperatae.

PubMed

Zhou, Xian-rong; Wang, Jian-hua; Jiang, Bo; Shang, Jin; Zhao, Chang-qiong

2013-01-01

The study investigated the extraction method of Rhizoma Imperatae and its antioxidant activity, and provided a basis for its rational development. The extraction method of Rhizoma Imperatae was determined using orthogonal design test and by total phenol content, its hydroxyl radical scavenging ability was measured by Fenton reaction, and potassium ferricyanide reduction method was used to determine its reducing power. The results showed that the optimum extraction process of Rhizoma Imperatae was a 50-fold volume of water, 30 °C, three times of extraction with 2 h each. Its IC50 for scavenging of hydroxyl radicals was 0.0948 mg/mL, while IC50 of ascorbic acid was 0.1096 mg/mL; in the ferricyanide considerable reduction method, the extract exhibited reducing power comparable to that of the ascorbic acid. The study concluded that Rhizoma Imperatae extract contains relatively large amount of polyphenols, and has a good anti-oxidation ability.

High dosage of ascorbic acid and alpha-tocopherol is not useful for diminishing oxidative stress and DNA damage in healthy elderly adults.

PubMed

Retana-Ugalde, Raquel; Casanueva, Esther; Altamirano-Lozano, Mario; González-Torres, Cristina; Mendoza-Núñez, Víctor Manuel

2008-01-01

To determine the useful dosage of ascorbic acid and alpha-tocopherol against oxidative stress and DNA damage in the elderly. 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 placebo and group B was administered 500 mg of ascorbic acid and 400 IU of alpha-tocopherol, whereas group C received 1,000 mg of ascorbic acid and 400 IU of alpha-tocopherol for a 6-month period. The following measurements were performed before and after the 6-month treatment period: thiobarbituric acid reactive substances (TBARS); total antioxidant status (TAS); superoxide dismutase (SOD), and glutation peroxidase (GPx) and DNA damage by comet assay. After 6 months, group B subjects exhibited an increase in SOD and GPx enzyme levels; however, this was not statistically significant (p > 0.05). Likewise, TBARS and TAS concentrations remained unchanged (p > 0.05). In addition, in group C the decrease in TBARS and increase in SOD, GPx, and TAS were not statistically significant (p > 0.05). Similarly, average DNA migration showed no significant differences with high-dosage ascorbic acid and alpha-tocopherol. These findings suggest that administration of 1,000 mg of ascorbic acid plus 400 IU of alpha-tocopherol for 6 months is not useful for diminishing oxidative stress and DNA damage in healthy elderly adults. 2008 S. Karger AG, Basel.

Variations in the phytochemical contents and antioxidant capacity of organically and conventionally grown Italian cauliflower (Brassica oleracea L. subsp. botrytis): results from a three-year field study.

PubMed

Lo Scalzo, Roberto; Picchi, Valentina; Migliori, Carmela Anna; Campanelli, Gabriele; Leteo, Fabrizio; Ferrari, Valentino; Di Cesare, Luigi Francesco

2013-10-30

A three-year field study (2009-2011) was performed to evaluate phytochemicals and antioxidant capacities of two genotypes (HF1 Emeraude and the local variety, Velox) of green cauliflower grown under organic and conventional management. The conventional system increased yield, but had little effect on the dry matter, whereas the organic system increased the soluble solids. Phytochemicals and antioxidant capacity showed significant year-to-year variability. During the third year, the scarce rainfall determined a significant increase of total glucosinolates and a general decrease of antioxidants in all samples. Interestingly, in the same year organic plants were less affected by the unfavorable climatic conditions, as they increased ascorbic acid, polyphenols, and carotenoids with respect to conventional ones. The overall results for the three years showed that the two genotypes responded differently. Compared to the conventional system, Velox showed 24, 21, 13, 48, and 44% higher content of ascorbic acid, polyphenols, carotenoids, volatiles, and antioxidant capacity, respectively. In contrast, no significant increase in the phytochemicals or the antioxidant potential was found in organic Emeraude, with the exception of total volatiles (+41%). These findings suggest that organic cultivation may be highly effective for particular cauliflower genotypes.

Antioxidant defense and oxidative stress in children with acute hepatitis A

PubMed Central

Popovic-Dragonjic, Lidija; Jovanovic, Maja; Vrbic, Miodrag; Konstantinovic, Ljiljana; Kostic, Velimir; Dragonjic, Ivan

2011-01-01

BACKGROUND AND OBJECTIVES: Published data on oxidative stress in children with acute hepatitis A are still very scarce. This study aims to evaluate the oxidant/antioxidant status of these patients. DESIGN AND SETTING: Prospective, case-control study, over 2.5 years in patients under hospitalized and ambulatory care. PATIENTS AND METHODS: The levels of a whole-blood antioxidant, reduced glutathione; and plasma antioxidants, β-carotene, retinol, ascorbic acid, α-tocopherol; and the biomarker of oxidative stress, malondialdehyde, were evaluated in 50 pediatric patients (age range, 5-16 years; 29 males and 21 females) with acute hepatitis A and in 50 healthy children as control subjects (age range, 5-16 years; 25 males and 25 females). RESULTS: Plasma levels of reduced glutathione, β-carotene, retinol, α-tocopherol and ascorbic acid were significantly lower, while malondialdehyde plasma levels were significantly increased in the patient group when compared to the controls (P<.0001 for all parameters). CONCLUSIONS: Our findings show that pediatric patients with acute hepatitis A were influenced by oxidative stress, resulting in significantly lower levels of plasma antioxidants and increased lipid peroxidation. In the absence of other therapeutic options, antioxidant vitamin supplements could be added to the therapy for these patients to help reestablish the oxidant status balance. Further investigations to confirm this suggestion are recommended. PMID:21623054

Degradation kinetics of chlorogenic acid at various pH values and effects of ascorbic acid and epigallocatechin gallate on its stability under alkaline conditions.

PubMed

Narita, Yusaku; Inouye, Kuniyo

2013-01-30

5-Caffeoylquinic acid (5-CQA) is generally referred to as chlorogenic acid and exhibits various biological activities such as antioxidant activity and porcine pancreas α-amylase inhibitory activities. 5-CQA may be useful as an antioxidant for food and to prevent diabetes and obesity. The degradation of 5-CQA and caffeic acid (CA) in an aqueous solution at 37 °C and pH 5.0-9.0 was studied. The degradation of 5-CQA and CA, demonstrating time and pH dependence (i.e., the rate constant, k, was higher at higher pH), was satisfactorily described by the Weibull equation. The stability of 5-CQA at pH 7.4 and 9.0 was improved by adding (-)-epigallocatechin gallate (EGCG) and ascorbic acid (AA). Moreover, the degradation of 5-CQA in the presence of EGCG or AA could be described by the Weibull equation. The k value in the presence of EGCG or AA was dependent on their concentration.

Involvement of abscisic acid in regulating antioxidative defense systems and IAA-oxidase activity and improving adventitious rooting in mung bean [Vigna radiata (L.) Wilczek] seedlings under cadmium stress.

PubMed

Li, Shi-Weng; Leng, Yan; Feng, Lin; Zeng, Xiao-Ying

2014-01-01

In vitro experiments were conducted to investigate the effects of abscisic acid (ABA) and Cd on antioxidative defense systems and indole-3-acetic acid (IAA) oxidase during adventitious rooting in mung bean [Vigna radiata (L.) Wilczek] seedlings. The exogenous ABA significantly enhanced the number and fresh weight of the adventitious roots. CdCl2 strongly inhibited adventitious rooting. Pretreatment with 10 μM ABA clearly alleviated the inhibitory effect of Cd on rooting. ABA significantly reduced superoxide dismutase (SOD), ascorbate peroxidase (APX), peroxidase (POD), and catalase (CAT) activities, as well as the levels of glutathione (GSH) and ascorbic acid (ASA) during adventitious rooting. ABA strongly increased IAA-oxidase activity during the induction (0-12 h) and expression (after 48 h) phases and increased the phenols levels. Cd treatment significantly reduced the activities of SOD, APX, POD, and IAA oxidase, as well as GSH level. Cd strongly increased ASA levels. ABA pretreatment counteracted Cd-induced alterations of certain antioxidants and antioxidative enzymes, e.g., remarkably rescued APX and POD activities, reduced the elevated SOD and CAT activities and ASA levels, and recovered the reduced GSH levels, caused by Cd stress. Thus, the physiological effects of the combination of ABA and Cd treatments were opposite of those obtained with Cd treatment alone, suggesting that ABA involved in the regulation of antioxidative defense systems and the alleviation of wounding- and Cd-induced oxidative stress.

Effects of boiling and in vitro gastrointestinal digestion on the antioxidant activity of Sonchus oleraceus leaves.

PubMed

Mawalagedera, S M M R; Ou, Zong-Quan; McDowell, Arlene; Gould, Kevin S

2016-03-01

Leaves of Sonchus oleraceus L. are especially rich in phenolic compounds and have potent extractable antioxidants. However, it is not known how their antioxidant activity changes after cooking and gastrointestinal digestion. We recorded the profile of phenolics and their associated antioxidant activity in both raw and boiled S. oleraceus leaf extracts after in vitro gastric and intestinal digestion, and quantified their antioxidant potentials using Caco-2 and HepG2 cells. Boiling significantly diminished the oxygen radical absorbance capacity (ORAC) and concentrations of ascorbate and chicoric acid in the soluble fractions. In contrast, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and concentrations of caftaric and chlorogenic acids were unaffected. Phenolics in the soluble fraction were absorbed into cultured human cells and exerted antioxidant activity. Only chlorogenic acid content remained stable during gastrointestinal digestion. S. oleraceus appears to be an excellent dietary source of phenolic antioxidants.

Antioxidant Compounds in Traditional Indian Pickles May Prevent the Process-Induced Formation of Benzene.

PubMed

Kharat, Mahesh M; Adiani, Vanshika; Variyar, Prasad; Sharma, Arun; Singhal, Rekha S

2016-01-01

Pickles in the Indian market contain ascorbic acid from the raw material used and benzoate as an added preservative that are involved in the formation of benzene in soft drinks. In this work, 24 market pickle samples were surveyed for benzene content, as well as its precursors and other constituents that influence its formation. The analysis showed that pickle samples were high in acid content (low pH) and showed significant amount of ascorbic acid, minerals (Cu and Fe), and benzoic acid present in them. Also, most samples exhibited high antioxidant activity that might be attributed to the ingredients used, such as fruits and spices. The solid-phase microextraction headspace gas chromatography-mass spectrometry method was developed in-house for benzene analysis. Eleven of 24 samples had benzene, with the highest concentration of 4.36 ± 0.82 μg of benzene per kg of pickle for a lime pickle that was also reported to have highest benzoic acid and considerably less hydroxyl radical ((•)OH) scavenging activity. However, benzene levels for all 11 samples were considerably below the World Health Organization regulatory limit of 10 μg/kg for benzene in mineral water. Studies on model systems revealed that the high antioxidant activity of Indian pickles may have had a strong inhibitory effect on benzene formation.

Infusion of Hibiscus sabdariffa L. Modulates Oxidative Stress in Patients with Marfan Syndrome.

PubMed

Soto, María Elena; Zuñiga-Muñoz, Alejandra; Guarner Lans, Verónica; Duran-Hernández, Erendira Janet; Pérez-Torres, Israel

2016-01-01

Marfan syndrome (MFS) is associated with progressive aortic dilatation, endothelial dysfunction, and oxidative stress that contribute to the early acute dissection of the vessel and can end up in rupture of the aorta and sudden death. Many studies have described that the organic acids from Hibiscus sabdariffa Linne (HSL) calyces increase cellular antioxidant capacity and decrease oxidative stress. Here we evaluate if the antioxidant properties of HSL infusion improve oxidative stress in MFS patients. Activities of extra cellular super oxide dismutase (ECSOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), glutathione reductase (GSSG-R), glutathione (GSH), lipid peroxidation (LPO) index, total antioxidant capacity (TAC), and ascorbic acid were determined in plasma from MFS patients. Values before and after 3 months of the treatment with 2% HSL infusion were compared in control and MFS subjects. After treatment, there was a significant decrease in ECSOD (p = 0.03), EGPx (p = 0.04), GST (p = 0.03), GSH (p = 0.01), and TAC and ascorbic acid (p = 0.02) but GSSG-R activity (p = 0.04) and LPO (p = 0.02) were increased in MFS patients in comparison to patients receiving the HSL treatment and C subjects. Therefore, the infusion of HSL calyces has antioxidant properties that allow an increase in antioxidant capacity of both the enzymatic and nonenzymatic systems, in the plasma of the MSF patients.

Chemical Composition and Antioxidant Properties of Powders Obtained from Different Plum Juice Formulations.

PubMed

Michalska, Anna; Wojdyło, Aneta; Łysiak, Grzegorz P; Figiel, Adam

2017-01-17

Among popular crops, plum ( Prunus domestica L.) has received special attention due to its health-promoting properties. The seasonality of this fruit makes it impossible to consume it throughout the year, so new products in a powder form may offer an alternative to fresh consumption and may be used as high-quality natural food ingredients. A 100% plum (cultivar "Valor") juice was mixed with three different concentrations of maltodextrin or subjected to sugars removal by amberlite-XAD column, and dried using the freeze, spray, and vacuum (40, 60, and 80 °C) drying techniques. The identification and quantification of phenolic acids, flavonols, and anthocyanins in plum powders was performed by LC-MS QTof and UPLC-PDA, respectively. l-ascorbic acid, hydroxymethylfurfural, and antioxidant capacity were measured by the Trolox equivalent antioxidant capacity (TEAC) ABTS and ferric reducing antioxidant potential (FRAP) methods in order to compare the influence of the drying methods on product quality. The results indicated that the profile of polyphenolic compounds in the plum juice powders significantly differed from the whole plum powders. The drying of a sugar free plum extract resulted in higher content of polyphenolic compounds, l-ascorbic acid and antioxidant capacity, but lower content of hydroxymethylfurfural, regardless of drying method applied. Thus, the formulation of plum juice before drying and the drying method should be carefully selected in order to obtain high-quality powders.

Chemical Composition and Antioxidant Properties of Powders Obtained from Different Plum Juice Formulations

PubMed Central

Michalska, Anna; Wojdyło, Aneta; Łysiak, Grzegorz P.; Figiel, Adam

2017-01-01

Among popular crops, plum (Prunus domestica L.) has received special attention due to its health-promoting properties. The seasonality of this fruit makes it impossible to consume it throughout the year, so new products in a powder form may offer an alternative to fresh consumption and may be used as high-quality natural food ingredients. A 100% plum (cultivar “Valor”) juice was mixed with three different concentrations of maltodextrin or subjected to sugars removal by amberlite-XAD column, and dried using the freeze, spray, and vacuum (40, 60, and 80 °C) drying techniques. The identification and quantification of phenolic acids, flavonols, and anthocyanins in plum powders was performed by LC-MS QTof and UPLC-PDA, respectively. l-ascorbic acid, hydroxymethylfurfural, and antioxidant capacity were measured by the Trolox equivalent antioxidant capacity (TEAC) ABTS and ferric reducing antioxidant potential (FRAP) methods in order to compare the influence of the drying methods on product quality. The results indicated that the profile of polyphenolic compounds in the plum juice powders significantly differed from the whole plum powders. The drying of a sugar free plum extract resulted in higher content of polyphenolic compounds, l-ascorbic acid and antioxidant capacity, but lower content of hydroxymethylfurfural, regardless of drying method applied. Thus, the formulation of plum juice before drying and the drying method should be carefully selected in order to obtain high-quality powders. PMID:28106740

Infusion of Hibiscus sabdariffa L. Modulates Oxidative Stress in Patients with Marfan Syndrome

PubMed Central

Soto, María Elena; Zuñiga-Muñoz, Alejandra; Guarner Lans, Verónica; Duran-Hernández, Erendira Janet; Pérez-Torres, Israel

2016-01-01

Marfan syndrome (MFS) is associated with progressive aortic dilatation, endothelial dysfunction, and oxidative stress that contribute to the early acute dissection of the vessel and can end up in rupture of the aorta and sudden death. Many studies have described that the organic acids from Hibiscus sabdariffa Linne (HSL) calyces increase cellular antioxidant capacity and decrease oxidative stress. Here we evaluate if the antioxidant properties of HSL infusion improve oxidative stress in MFS patients. Activities of extra cellular super oxide dismutase (ECSOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), glutathione reductase (GSSG-R), glutathione (GSH), lipid peroxidation (LPO) index, total antioxidant capacity (TAC), and ascorbic acid were determined in plasma from MFS patients. Values before and after 3 months of the treatment with 2% HSL infusion were compared in control and MFS subjects. After treatment, there was a significant decrease in ECSOD (p = 0.03), EGPx (p = 0.04), GST (p = 0.03), GSH (p = 0.01), and TAC and ascorbic acid (p = 0.02) but GSSG-R activity (p = 0.04) and LPO (p = 0.02) were increased in MFS patients in comparison to patients receiving the HSL treatment and C subjects. Therefore, the infusion of HSL calyces has antioxidant properties that allow an increase in antioxidant capacity of both the enzymatic and nonenzymatic systems, in the plasma of the MSF patients. PMID:27413258

ASCORBID ACID IS DECREASED IN INDUCED SPUTUM OF MILD ASTHMATICS

EPA Science Inventory

ABSTRACT
Evidence suggests that the antioxidant ascorbic acid (AA), plays an essential role in defending against oxidant attack in the airways. Decreased levels of AA have been reported in asthmatics but not at the site directly proximal to asthma pathology, i.e. the bronchial...

Enhanced erythrocytic lipid peroxides and reduced plasma ascorbic acid, and alteration in blood trace elements level in dairy cows with mastitis.

PubMed

Ranjan, R; Swarup, D; Naresh, R; Patra, R C

2005-01-01

Oxidative stress has been associated in several inflammatory conditions and incriminated in the pathogenesis of many diseases. However, little information is available on the status of plasma antioxidant levels, essential components of important antioxidant enzymes such as copper, zinc and selenium in blood, and the end product of oxidative damage to the erythrocytic polyunsaturated fatty acids in inflammatory udder conditions. Blood samples were collected from three groups of dairy cows, with 21 in each group: animals with healthy udder, clinical mastitis, and subclinical mastitis. These animals were randomly selected from a herd on the basis of the California mastitis test, somatic cell count and total bacterial count. The mean plasma ascorbic acid concentration was significantly lower in cows with subclinical (p = 0.004) and clinical mastitis (p = 0.000) and the erythrocytic lipid peroxide levels were significantly (p = 0.000) higher in clinical mastitis as compared to controls. There was a significant decrease in mean blood zinc concentration in subclinical (p = 0.005) and clinical mastitis (p = 0.000), but an increase in mean blood copper level in the clinical mastitis group. It was concluded that the blood antioxidant status declines in inflammatory udder conditions, suggesting that incorporation of antioxidants may help in better management of mastitis in dairy cows.

Antimicrobial and antioxidant activities of Mimusops elengi seed extract mediated isotropic silver nanoparticles

NASA Astrophysics Data System (ADS)

Kiran Kumar, Hoskote Anand; Mandal, Badal Kumar; Mohan Kumar, Kesarla; Maddinedi, Sireesh babu; Sai Kumar, Tammina; Madhiyazhagan, Pavithra; Ghosh, Asit Ranjan

2014-09-01

The present study reports the use of Mimusops elengi (M. elengi) fruit extract for the synthesis of silver nanoparticles (Ag NPs). The synthesized Ag NPs was initially noticed through visual color change from yellow to reddish brown and further confirmed by surface plasmonic resonance (SPR) band at 429 nm using UV-Visible spectroscopy. Morphology and size of Ag NPs was determined by Transmission Electron Microscopy (TEM) analysis. X-ray Diffraction (XRD) study revealed crystalline nature of Ag NPs. The prolonged stability of Ag NPs was due to capping of oxidized polyphenols which was established by Fourier Transform Infrared Spectroscopy (FTIR) study. The polyphenols present in M. elengi fruit extract was analyzed by High Pressure Liquid Chromatography (HPLC) and the results revealed the presence of ascorbic acid, gallic acid, pyrogallol and resorcinol. In order to study the role of these polyphenols in reducing Ag+ ions to Ag NPs, analyses of extracts before reduction and after reduction were carried out. In addition, the synthesized Ag NPs were tested for antibacterial and antioxidant activities against Staphylococcus aureus (S. Aureus) and Escherichia coli (E. coli). Ag NPs showed good antimicrobial activity against both gram positive (S. aureus) and gram negative (E. coli) bacteria. It also showed good antioxidant activity as compared to ascorbic acid as standard antioxidant.

Ascorbic acid co-administered with rosuvastatin reduces reproductive impairment in the male offspring from male rats exposed to the statin at pre-puberty.

PubMed

Leite, Gabriel Adan Araújo; Figueiredo, Thamiris Moreira; Guerra, Marina Trevizan; Borges, Cibele Dos Santos; Fernandes, Fábio Henrique; Anselmo-Franci, Janete Aparecida; Kempinas, Wilma De Grava

2018-05-18

Obesity during childhood and adolescence is closely related to dysfunctions on lipid profile in children. Rosuvastatin is a statin that decreases serum total cholesterol. Ascorbic acid is an important antioxidant compound for male reproduction. Pre-pubertal male rats were distributed into six experimental groups that received saline solution 0.9% (vehicle), 3 or 10 mg/kg/day of rosuvastatin, 150 mg/day of ascorbic acid, or 3 or 10 mg/kg/day of rosuvastatin co-administered with 150 mg/day of ascorbic acid by gavage from post-natal day (PND)23 until PND53. Rats were maintained until adulthood and mated with nulliparous females to obtain the male offspring, whose animals were evaluated at adulthood in relation to reproductive parameters. This study is a follow up of a previous paper addressing potential effects on F0 generation only (Leite et al., 2017). Male offspring from rosuvastatin-exposed groups showed increased sperm DNA fragmentation, androgen depletion and impairment on the testicular and epididymal structure. Ascorbic acid coadministered to the fathers ameliorated the reproductive damage in the offspring. In summary, paternal exposure to rosuvastatin may affect the reproduction in the male offspring; however, paternal supplementation with ascorbic acid was able to reduce the reproductive impairment in the male offspring caused by statin treatment to the fathers. Copyright © 2018 Elsevier Ltd. All rights reserved.

Influence of ageing process on body composition of antioxidant and lipid peroxidation among healthy individuals in South West Nigeria.

PubMed

Ogunro, P S; Ogungbamigbe, T O

2013-03-01

To evaluate the effect of ageing on the level of antioxidants and lipid peroxidation in healthy individual of various age groups. A total number of 162 healthy males and females volunteer between the ages of 18-80 years were divided into three groups. These volunteers were divided into group i(18-30 yr), group ii (31-60 yrs) and group iii (60-80 yr). Plasma concentration of total bilirubin, uric acid, ascorbic acid, a-tocopherol, retinol, total antioxidant status (TAS), malondialdehyde (MDA), glutathione (GSH) and ceruloplasmin measured. Erythrocyte antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT), glutathione and peroxidase (GSHPx) were measured using standard methods. Erythrocyte antioxidant enzymes (GSH-Px and SOD) activities and GSH level were significantly reduced among group iii (p<0.01) and group ii (p<0.05) age group subjects compared to the younger age group i. Conversely, MDA showed a significant increase in group iii (p<0.01) and group ii (p<0.01) compared to younger age group i. CAT activity and TAS level were reduced significantly (p<0.05) in both groups iii and ii compared to younger age group i. Ascorbic acid, a-tocopherol and retinol levels were significantly reduced among group iii (p<0.05) compared to group i. Ageing was associated with increased lipid peroxidation and lower antioxidant defenses. Changes that occur during ageing cannot be avoided but may be delayed and controlled to some extent. To counter these changes, dietary supplementation of a variety of antioxidants might be beneficial.

Catalytic therapy of cancer by ascorbic acid involves redox cycling of exogenous/endogenous copper ions and generation of reactive oxygen species.

PubMed

Hadi, S M; Ullah, M F; Shamim, U; Bhatt, S H; Azmi, A S

2010-01-01

Catalytic therapy is a cancer treatment modality based on the generation of reactive oxygen species (ROS) through administration of ascorbate/medicinal herbal extracts and copper. It is known that antioxidants such as ascorbate also exhibit prooxidant activity in the presence of transition metals such as copper. Based on our work and that in the literature, in this review we propose a mechanism for the cytotoxic action of ascorbate against cancer cells. It involves redox cycling of exogenous/endogenous copper ions and the consequent generation of ROS leading to oxidative DNA breakage. Using human peripheral lymphocytes and the Comet assay, we have shown that ascorbic acid is able to cause oxidative breakage in cellular DNA. Such DNA degradation is inhibited by neocuproine (a Cu(I) sequestering agent) and scavengers of ROS indicating that the cellular DNA breakage involves the generation of Cu(I) and formation of ROS. Similar results are also obtained with plant polyphenol antioxidants that are important constituents of medicinal herbal extracts. Copper is an essential component of chromatin and can take part in redox reactions. It is well established that tissue, cellular and serum copper levels are considerably elevated in various malignancies. Therefore, cancer cells may be more subject to electron transfer between copper ions and ascorbate/plant polyphenols to generate ROS. In this review we cite evidence to indicate that in catalytic therapy cytotoxic action against cancer cells involves redox cycling of exogenous/endogenous copper ions. Copyright © 2010 S. Karger AG, Basel.

Antioxidant Defenses in Plants with Attention to Prunus and Citrus spp.

PubMed Central

Racchi, Milvia Luisa

2013-01-01

This short review briefly introduces the formation of reactive oxygen species (ROS) as by-products of oxidation/reduction (redox) reactions, and the ways in which the antioxidant defense machinery is involved directly or indirectly in ROS scavenging. Major antioxidants, both enzymatic and non enzymatic, that protect higher plant cells from oxidative stress damage are described. Biochemical and molecular features of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) are discussed because they play crucial roles in scavenging ROS in the different cell compartments and in response to stress conditions. Among the non enzymatic defenses, particular attention is paid to ascorbic acid, glutathione, flavonoids, carotenoids, and tocopherols. The operation of ROS scavenging systems during the seasonal cycle and specific developmental events, such as fruit ripening and senescence, are discussed in relation to the intense ROS formation during these processes that impact fruit quality. Particular attention is paid to Prunus and Citrus species because of the nutritional and antioxidant properties contained in these commonly consumed fruits. PMID:26784469

Comparative transcriptomic profiling of two tomato lines with different ascorbate content in the fruit.

PubMed

Di Matteo, Antonio; Sacco, Adriana; De Stefano, Rosalba; Frusciante, Luigi; Barone, Amalia

2012-12-01

In recent years, interest in tomato breeding for enhanced antioxidant content has increased as medical research has pointed to human health benefits from antioxidant dietary intake. Ascorbate is one of the major antioxidants present in tomato, and little is known about mechanisms governing ascorbate pool size in this fruit. In order to provide further insights into genetic mechanisms controlling ascorbate biosynthesis and accumulation in tomato, we investigated the fruit transcriptome profile of the Solanum pennellii introgression line 10-1 that exhibits a lower fruit ascorbate level than its cultivated parental genotype. Our results showed that this reduced ascorbate level is associated with an increased antioxidant demand arising from an accelerated oxidative metabolism mainly involving mitochondria, peroxisomes, and cytoplasm. Candidate genes for controlling ascorbate level in tomato fruit were identified, highlighting the role of glycolysis, glyoxylate metabolism, and purine breakdown in modulating the ascorbate pool size.

Phytochemical investigations and antioxidant potential of roots of Leea macrophylla (Roxb.).

PubMed

Mahmud, Zobaer Al; Bachar, Sitesh C; Hasan, Choudhury Mahmood; Emran, Talha Bin; Qais, Nazmul; Uddin, Mir Muhammad Nasir

2017-07-06

Oleanolic acid (NZ-15), 7 α, 28-olean diol (NZ-38) and Stigmasterol (NZ-14) were isolated from the ethanolic extracts of the roots of Leea macrophylla (Family: Leeaceae) by using chromatographic analysis. This is the first report of isolation of these compounds from this plant. Their structures were constructed by spectroscopic analysis and by comparing the data with the published one. Subsequently the ethanolic extract was fractionated with two organic solvents and all the fractions were studied to evaluate their in vitro antioxidant property. The ethanolic extract was fractionated with two organic solvents and all the fractions were studied to evaluate their in vitro antioxidant property by DPPH free radical scavenging assay, superoxide anion radical scavenging assay, nitric oxide radical scavenging assay, and reducing power assay. In the DPPH free radical scavenging assay and superoxide radical scavenging assay, the ethyl acetate soluble fraction of ethanolic extract revealed the highest free radical scavenging activity with IC 50 value of 2.65 and 155.62 μg/ml, respectively as compared to standard ascorbic acid (IC 50 value of 5.8 and 99.66 μg/ml). Ethyl acetate fraction also possessed highest reducing power activity with an EC50 value of 15.27 μg/ml compared to ascorbic acid (EC 50 0.91 μg/ml). On the other hand, the carbon tetrachloride fraction exhibited most significant NO scavenging activity with IC 50 value of 277.8 μg/ml that was even higher than that of standard ascorbic acid (IC 50 value 356.04 μg/ml). In addition, the total phenolic contents of these extract and fractions were evaluated using Folin-Ciocalteu reagent and varied from 7.93 to 50.21 mg/g dry weight expressed as gallic acid equivalents (GAE). This study showed that different extracts of roots of L. macrophylla possess potential DPPH, superoxide, and NO free radical scavenging activities. The antioxidant activities of the plant extracts might be due to the presence of oleanolic acid, oleanolic acid derivative 7 α, 28-olean diol and stigmasterol.

In vitro antioxidant activity of Retama monosperma (L.) Boiss.

PubMed

Belmokhtar, Zoubir; Harche, Meriem Kaid

2014-01-01

The relationship between the antioxidant activity and the phenolic contents (total polyphenol, flavonoid and condensed tannin) of Retama monosperma (Fabaceae), used commonly in the traditional medicine of Mediterranean regions, was investigated. The antioxidant activities of the various fractions (toluene, chloroform, ethyl acetate and butanol) of the hydromethanolic extract of the seeds, stems and flowers have been evaluated using in vitro 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) radical scavenging activities and Phosphomolybdic acid assays and were compared to ascorbic acid. A significant high Pearson's correlations between flavonoid content and antioxidant activities (r = 0.91) with Phosphomolybdic acid assays and (r = - 0.79) with IC50 DPPH radical scavenging activities. However, there was no correlation between condensed tannin and antioxidant activities. The results obtained in the present study indicate that the ethyl acetate fraction of seeds is a potential source of natural antioxidant for R. monosperma.

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

PubMed Central

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

2016-01-01

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

Influence of the interactions between tea (Camellia sinensis) extracts and ascorbic acid on their antioxidant activity: analysis with interaction indexes and isobolograms.

PubMed

Enko, Jolanta; Gliszczyńska-Świgło, Anna

2015-01-01

Products containing natural additives, including antioxidants, are usually perceived by consumers as safer than those with synthetic ones. Natural antioxidants, besides having a preservative activity, may exert beneficial health effects. Interactions between antioxidants may significantly change their antioxidant activity, thus in designing functional foods or food/cosmetic ingredients knowledge about the type of interactions could be useful. In the present study, the interactions between ascorbic acid (AA; vitamin C) and different black and green tea extracts and the influence on their antioxidant activities were investigated. The antioxidant activities of tea extracts and their mixtures with AA prepared in several different weight ratios were measured using the trolox equivalent antioxidant capacity (TEAC), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and ferric-reducing antioxidant power (FRAP) methods. The type of interaction was determined by interaction indexes and isobolograms. It was found that the weight ratio of extracts to AA significantly influenced the antioxidant activity of a mixture and the type of interaction between these components. The weight ratio of tea extract to AA can cause the change of interaction, e.g. from antagonism to additivism or from additivism to synergism. The observed differences in the type of interactions were probably also a result of different extracts' polyphenol composition and content. The type of interaction may also be affected by the medium in which extracts and AA interact, especially its pH and the solvent used. To obtain the best antioxidant effect, all these factors should be taken into account during the design of a tea extract-AA mixture.

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

PubMed

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

2010-06-01

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

Indole-3-butyric acid mediates antioxidative defense systems to promote adventitious rooting in mung bean seedlings under cadmium and drought stresses.

PubMed

Li, Shi-Weng; Zeng, Xiao-Ying; Leng, Yan; Feng, Lin; Kang, Xiao-Hu

2018-06-08

In vitro experiments were performed to determine whether auxin can mediate the formation of adventitious roots in response to heavy metal and drought stresses using a model rooting plant, mung bean [Vigna radiata (L.) Wilczek]. The treatments with CdCl 2 or mannitol alone significantly inhibited the formation and growth of adventitious roots in mung bean seedlings. In contrast, when CdCl 2 or mannitol was applied together with indole-3-butyric acid (IBA), IBA considerably cancelled the inhibition of adventitious rooting by stresses. Treatment with CdCl 2 or mannitol alone significantly increased the soluble protein and malondialdehyde (MDA) contents. CdCl 2 and mannitol stress each induced differentially significant changes in the activities of antioxidative enzyme and antioxidant levels during adventitious rooting. Notably, both CdCl 2 and mannitol stress strongly reduced the peroxidase (POD) and ascorbate peroxidase (APX) activities and glutathione (GSH) and phenols levels. Catalase and superoxide dismutase (SOD) activity were enhanced by CdCl 2 but reduced by mannitol. CdCl 2 increased the ascorbate acid (ASA) level, which was decreased by mannitol. Furthermore, when CdCl 2 or mannitol was applied together with IBA, IBA counteracted the CdCl 2 - or mannitol-induced increase or decrease in certain antioxidants, MDA, and antioxidative enzymes. These results suggest that Cd and mannitol stress inhibition of adventitious rooting is associated with the regulation of antioxidative enzymes and antioxidants in cells to defense the oxidative stress. Moreover, IBA alleviates the effects of Cd and mannitol stress on the rooting process partially through the regulation of antioxidative defense systems. Copyright © 2018 Elsevier Inc. All rights reserved.

Sensorially important aldehyde production from amino acids in model wine systems: impact of ascorbic acid, erythorbic acid, glutathione and sulphur dioxide.

PubMed

Grant-Preece, Paris; Fang, Hongjuan; Schmidtke, Leigh M; Clark, Andrew C

2013-11-01

The efficiency of different white wine antioxidant systems in preventing aldehyde production from amino acids by oxidative processes is not well understood. The aim of this study was to assess the efficiency of sulphur dioxide alone and in combination with either glutathione, ascorbic acid or its stereoisomer erythorbic acid, in preventing formation of the sensorially important compounds methional and phenylacetaldehyde from methionine and phenylalanine in model white wine. UHPLC, GC-MS/MS, LC-MS/MS, flow injection analysis and luminescence sensors determined both compositional changes during storage, and sulphur dioxide-aldehyde apparent equilibrium constants. Depending on temperature (25 or 45°C) or extent of oxygen supply, sulphur dioxide was equally or more efficient in impeding the production of methional compared to the other antioxidant systems. For phenylacetaldehyde, erythorbic acid or glutathione with sulphur dioxide provided improved inhibition compared to sulphur dioxide alone, in conditions of limited oxygen consumption. The results also demonstrate the extent to which sulphur dioxide addition can lower the free aldehyde concentrations to below their aroma thresholds. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of Organic and Conventional Management on Bio-Functional Quality of Thirteen Plum Cultivars (Prunus salicina Lindl.).

PubMed

Cuevas, Francisco Julián; Pradas, Inmaculada; Ruiz-Moreno, María José; Arroyo, Francisco Teodoro; Perez-Romero, Luis Felipe; Montenegro, José Carlos; Moreno-Rojas, José Manuel

2015-01-01

In this study, thirteen Japanese plum cultivars (Prunus salicina Lindl.) grown under conventional and organic conditions were compared to evaluate the influence of the culture system on bioactive compounds. Their organic acids content (malic, citric, tartaric, succinic, shikimic, ascorbic and fumaric acid), total polyphenols, total anthocyanins, total carotenoids and antioxidant capacity (FRAP, ABTS) were evaluated. The study was performed during two consecutive seasons (2012 and 2013) in two experimental orchards located at the IFAPA centre Las Torres-Tomejil (Seville, SW Spain). The culture system affected all the studied parameters except for total carotenoid content. The organic plums had significantly higher polyphenol and anthocyanin concentrations and a greater antioxidant capacity. Additionally, significant differences between cultivars were also found. 'Showtime' and 'Friar' were the cultivars with the highest polyphenol concentration and antioxidant capacity. 'Black Amber' had the highest anthocyanin content and 'Larry Ann' and 'Songold' the highest carotenoid content. 'Sapphire' and 'Black amber' were the cultivars with the highest concentration of ascorbic acid. Our results showed a strong year effect. In conclusion, organic management had an impact on the production of phytochemical compounds in plums.

Effect of Organic and Conventional Management on Bio-Functional Quality of Thirteen Plum Cultivars (Prunus salicina Lindl.)

PubMed Central

Cuevas, Francisco Julián; Pradas, Inmaculada; Ruiz‐Moreno, María José; Arroyo, Francisco Teodoro; Perez-Romero, Luis Felipe; Montenegro, José Carlos; Moreno‐Rojas, José Manuel

2015-01-01

In this study, thirteen Japanese plum cultivars (Prunus salicina Lindl.) grown under conventional and organic conditions were compared to evaluate the influence of the culture system on bioactive compounds. Their organic acids content (malic, citric, tartaric, succinic, shikimic, ascorbic and fumaric acid), total polyphenols, total anthocyanins, total carotenoids and antioxidant capacity (FRAP, ABTS) were evaluated. The study was performed during two consecutive seasons (2012 and 2013) in two experimental orchards located at the IFAPA centre Las Torres-Tomejil (Seville, SW Spain). The culture system affected all the studied parameters except for total carotenoid content. The organic plums had significantly higher polyphenol and anthocyanin concentrations and a greater antioxidant capacity. Additionally, significant differences between cultivars were also found. ‘Showtime’ and ‘Friar’ were the cultivars with the highest polyphenol concentration and antioxidant capacity. ‘Black Amber’ had the highest anthocyanin content and ‘Larry Ann’ and ‘Songold’ the highest carotenoid content. ‘Sapphire’ and ‘Black amber’ were the cultivars with the highest concentration of ascorbic acid. Our results showed a strong year effect. In conclusion, organic management had an impact on the production of phytochemical compounds in plums. PMID:26313546

Antioxidant potential of n-butanol fraction from extract of Jasminum mesnyi Hance leaves.

PubMed

Borar, Sakshi; Punia, Priyanka; Kalia, A N

2011-01-01

Methanolic extract of Jasminum mesnyi Hance leaves having antidiabetic activity was subjected to fractionation to obtain antioxidant and antihyperglycemic rich fraction. Different concentrations of ethyl acetate and n-butanol fractions were subjected to antioxidant assay by DPPH method, nitric oxide scavenging activity and reducing power assay. The fractions showed dose dependent free radical scavenging property in all the models. IC50 values for ethyl acetate and n-butanol fractions were 153.45 +/- 6.65 and 6.22 +/- 0.25 microg/ml, respectively, as compared to L-ascorbic acid and rutin (as standards; IC50 values 6.54 +/- 0.24 and 5.43 +/- 0.21 microg/ml, respectively) in DPPH model. In nitric oxide scavenging activity, IC50 values were 141.54 +/- 9.95 microg/ml, 35.12 +/- 1.58 microg/ml, 21.06 +/- 0.95 microg/ml and 29.93 +/- 0.32 microg/ml for ethyl acetate, n-butanol fractions, L-ascorbic acid and rutin, respectively. n-Butanol fraction showed a good reducing potential and better free radical scavenging activity as compared to ethyl acetate fraction. Potent antioxidant n-butanol fraction showed better oral glucose tolerance test (antihyperglycemic) at par with metformin (standard drug), n-Butanol fraction contained secoiridoid glycosides which might be responsible for both antioxidant and antihyperglycemic activity.

Screening chemical composition and in vitro antioxidant and antimicrobial activities of the essential oils from Origanum syriacum L. growing in Turkey.

PubMed

Alma, Mehmet Hakki; Mavi, Ahmet; Yildirim, Ali; Digrak, Metin; Hirata, Toshifumi

2003-12-01

In the present study, essential oil from the leaves of Syrian oreganum [Origanum syriacum L. (Lauraceae)] grown in Turkish state forests of the Dortyol district, Turkey, was obtained by steam distillation. The chemical composition of oil was analysed by GC and GC-MS, and was found to contain 49.02% monoterpenes, 36.60% oxygenated monoterpenes and 12.59% sesquiterpenes. The major components are as follows: gamma-terpinene, carvacrol, p-cymene and beta-caryophyllene. Subsequently, the reducing power, antioxidant and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activities of the essential oil were studied. The reducing power was compared with ascorbic acid, and the other activities were compared with 2,6-di-tert-butyl-4-methyl phenol (BHT, butylated hydroxytoluene). The results showed that the activities were concentration dependent. The antioxidant activities of the oil were slightly lower than those of ascorbic acid or BHT, so the oil can be considered an effective natural antioxidant. Antimicrobial activities of the essential oil from the leaves of Origanum syriacum was also determined on 16 microorganisms tested using the agar-disc diffusion method, and showed antimicrobial activity against 13 of these.

Impact of exogenous ascorbic acid on biochemical activities of rice callus treated with salt stress

NASA Astrophysics Data System (ADS)

Alhasnawi, Arshad Naji; Zain, Che Radziah Che Mohd; Kadhimi, Ahsan A.; Isahak, Anizan; Mohamad, Azhar; Ashraf, Mehdi Farshad; Doni, Febri; Yusoff, Wan Mohtar Wan

2016-11-01

The application of in vitro systems can lead to new methods of crop amelioration. This method has been widely utilized for breeding tenacities, particularly for stress tolerance selection. Salinity causes oxidative stress in callus by enhancing the production of Reactive Oxygen Species (ROS), resulting in an efficient antioxidant system. The exogenous application of ascorbic acid (AsA) is an important requirement for tolerance. The present study aimed to examine in vitro selection strategy for callus induction in rice mature embryo culture on MS culture medium and to produce salt-tolerant callus under sodium chloride (NaCl) and AsA conditions in callus rice variety, MR269. This study also highlights changes in the activities of proline and antioxidants peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) of callus under NaCl stress to understand their possible role in salt tolerance. However, various levels of exogenously applied AsA under saline conditions improved callus, and the antioxidant enzyme activities of AsA are related to resistance to oxidative stress. Our results provide strong support for the hypothesis that AsA-dependent antioxidant enzymes play a significant role in the salinity tolerance of callus rice.

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

PubMed

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

2013-09-01

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

Reversible Reduction of Nitroxides to Hydroxylamines: the Roles for Ascorbate and Glutathione

PubMed Central

Bobko, Andrey A.; Kirilyuk, Igor A.; Grigor'ev, Igor A.; Zweier, Jay L.; Khramtsov, Valery V.

2007-01-01

Biological applications of stable nitroxyl radicals, NR, include their use as contrast agents for magnetic resonance imaging, spin labels, superoxide dismutase mimics, and antioxidants. The rapid reduction of NR in biological samples into hydroxylamines, HA, significantly limits their application. In its turn, reoxidation of HA back to the NR has been used for detection of reactive oxygen species, ROS. In this work comparative studies of the reduction of pyrrolidine, imidazoline and imidazolidine NR by ascorbate were performed taking advantage of recently synthesized tetraethyl substituted NR with much higher stability towards reduction both in vitro and in vivo. Surprisingly, these NR kept 10-50% of initial intensity of electron paramagnetic resonance signal for about 1 h in the presence of hundred fold excess of ascorbate. To explain this data, reoxidation of the corresponding HA by ascorbate radical and dehydroascorbic acid back to the NR was proposed. This hypothesis was supported by direct measurement of the NR appearance from the HA upon ascorbate radical generation by ascorbate oxidase, or in the presence of the dehydroascorbic acid. The reversible reaction between NR and ascorbate was observed for the various types of the NR, and the rate constants for direct and reverse reactions were determined. The equilibrium constants for one-electron reduction of the tetraethyl substituted NR by ascorbate were found to be in the range from 2.65×10−6 to 10−5 which is significantly lower than corresponding values for the tetramethyl substituted NR (less or about 10−4). This explains an establishment of EPR-detectable quasi-equilibrium level of tetraethyl substituted NR in the presence of excess of ascorbate. The redox reactions of the NR-HA couple in ascorbate containing medium was found to be significantly affected by glutathione, GSH. This effect was attributed to the reduction of ascorbate radical by GSH, and the rate constant of this reaction was found to be equal to 10 M−1s−1. In summary, the data provide new insight into the redox chemistry of NR and HA, and significantly affect interpretation and strategy of their use as redox- and ROS-sensitive probes, or as antioxidants. PMID:17210453

Assessment of antioxidant activity by using different in vitro methods.

PubMed

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

2002-02-01

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

Beyond the antioxidant: the double life of vitamin C.

PubMed

De Tullio, Mario C

2012-01-01

When considering the history of vitamin C, and the names given to this molecule in early days, the Latin proverb nomen est omen suddenly comes to mind. Around 1920, when Casimir Funk introduced the term Vitamin C to indicate the nutritional factor necessary to prevent the pathological state known as scurvy, the nature of the active molecule was still unknown (Davies MB, Austin J, Partridge DA (1991) Vitamin C: Its chemistry and biochemistry. The Royal Society of Chemistry, Cambridge UK). Almost in the same years, Albert Szent-Giörgyi was striving to identify a new 6-carbon sugar he had obtained in crystal form from oranges, lemons, cabbage and adrenal glands. As humorously described by Szent-Giörgyi himself (Szent-Giörgyi A (1963) Lost in the twentieth century. Annu Rev Biochem 36:1-15), he intended to name this yet unknown carbohydrate "ignose". When this name was rejected by Sir Arthur Harden, editor of the Biochemical Journal, he suggested to name it "godnose", meaning that only God could know the real identity of the molecule. Obviously, also this choice was considered inappropriate by Harden, who suggested the plain name "hexuronic acid". Only later, when the structure of "hexuronic acid" had been completely elucidated, and biological tests performed by Swirbely identified this molecule as the anti-scurvy factor vitamin C, Szent-Giörgyi and Walter Norman Haworth decided to eventually name it ascorbic acid (Szent-Giörgyi A (1963) Lost in the twentieth century. Annu Rev Biochem 36:1-15). "Ascorbic" literally means "against scurvy", and scurvy is known to be mainly due to the inactivation of some important dioxygenases involved in the synthesis of a few key molecules, including different collagen forms (De Tullio MC (2004) How does ascorbic acid prevent scurvy? A survey of the nonantioxidant functions of vitamin C. In: Asard H, May J, Smirnoff N (eds) Vitamin C, its functions and biochemistry in animals and plants. Bios Scientific Publishers, Oxford, UK, pp. 159-172). All this has very little to do with the celebrated role of ascorbic acid (ASC) as an antioxidant. So, if the fate of ASC had to be found in its name, its role in the prevention of scurvy (i.e. beyond the antioxidant function) should be considered its main feature. But, in spite of more than 80 years of extensive research (34,424 hits in a PubMed query on January 6 2007), an unprecedented popularity among the general public, an estimated market of several billion dollars (Hancock RD, Viola R (2005) Improving the nutritional value of crops through enhancement of l-ascorbic acid (vitamin C) content: Rationale and biotechnological opportunities. J Agr Food Chem 53:5248-5257), we should honestly conclude that the fate of vitamin C is still in the first name it received, many years ago: we still ignore much of its actual relevance in cell metabolism, although we are progressively getting aware of the many facets of this fascinating molecule, and its direct involvement in the regulation of apparently unrelated pathways (Arrigoni O, De Tullio MC (2002) Ascorbic acid, much more than just an antioxidant. Biochim Biophys Acta 1569:1-9; De Tullio MC, Arrigoni O (2004) Hopes, disillusions and more hopes from vitamin C. Cell Mol Life Sci 61:209-219; Duarte TL, Lunec J (2005) When is an antioxidant not an antioxidant? A review of novel actions and reactions of vitamin C. Free Rad Res 39:671-686). Recent data on ASC involvement in cell signalling and gene expression open new perspectives, that will be presented and discussed in this chapter.

Transcriptome mining and in silico structural and functional analysis of ascorbic acid and tartaric acid biosynthesis pathway enzymes in rose-scanted geranium.

PubMed

Narnoliya, Lokesh K; Sangwan, Rajender S; Singh, Sudhir P

2018-06-01

Rose-scented geranium (Pelargonium sp.) is widely known as aromatic and medicinal herb, accumulating specialized metabolites of high economic importance, such as essential oils, ascorbic acid, and tartaric acid. Ascorbic acid and tartaric acid are multifunctional metabolites of human value to be used as vital antioxidants and flavor enhancing agents in food products. No information is available related to the structural and functional properties of the enzymes involved in ascorbic acid and tartaric acid biosynthesis in rose-scented geranium. In the present study, transcriptome mining was done to identify full-length genes, followed by their bioinformatic and molecular modeling investigations and understanding of in silico structural and functional properties of these enzymes. Evolutionary conserved domains were identified in the pathway enzymes. In silico physicochemical characterization of the catalytic enzymes revealed isoelectric point (pI), instability index, aliphatic index, and grand average hydropathy (GRAVY) values of the enzymes. Secondary structural prediction revealed abundant proportion of alpha helix and random coil confirmations in the pathway enzymes. Three-dimensional homology models were developed for these enzymes. The predicted structures showed significant structural similarity with their respective templates in root mean square deviation analysis. Ramachandran plot analysis of the modeled enzymes revealed that more than 84% of the amino acid residues were within the favored regions. Further, functionally important residues were identified corresponding to catalytic sites located in the enzymes. To, our best knowledge, this is the first report which provides a foundation on functional annotation and structural determination of ascorbic acid and tartaric acid pathway enzymes in rose-scanted geranium.

Antioxidant effects of nerolidol in mice hippocampus after open field test.

PubMed

Nogueira Neto, José Damasceno; de Almeida, Antonia Amanda Cardoso; da Silva Oliveira, Johanssy; Dos Santos, Pauline Sousa; de Sousa, Damião Pergentino; de Freitas, Rivelilson Mendes

2013-09-01

The aim of this study was to evaluate the neuroprotective effects of nerolidol in mice hippocampus against oxidative stress in neuronal cells compared to ascorbic acid (positive control) as well as evaluated the nerolidol sedative effects by open field test compared to diazepam (positive control). Thirty minutes prior to behavioral observation on open field test, mice were intraperitoneally treated with vehicle, nerolidol (25, 50 and 75 mg/kg), diazepam (1 mg/kg) or ascorbic acid (250 mg/kg). To clarify the action mechanism of of nerolidol on oxidative stress in animals subjected to the open field test, Western blot analysis of Mn-superoxide dismutase and catalase in mice hippocampus were performed. In nerolidol group, there was a significant decrease in lipid peroxidation and nitrite levels when compared to negative control (vehicle). However, a significant increase was observed in superoxide dismutase and catalase activities in this group when compared to the other groups. Vehicle, diazepam, ascorbic acid and nerolidol groups did not affected Mn-superoxide dismutase, catalase mRNA or protein levels. Our findings strongly support the hypothesis that oxidative stress occurs in hippocampus. Nerolidol showed sedative effects in animals subjected to the open field test. Oxidative process plays a crucial role on neuronal pathological consequence, and implies that antioxidant effects could be achieved using this sesquiterpene.

Comparison of the rates of ozonation of biological antioxidants and oleate and linoleate esters

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

Giamalva, D.; Church, D.F.; Pryor, W.A.

1985-12-17

The rates of reaction with ozone of some biological antioxidants and simple polyunsaturated fatty acids (PUFA) have been measured in water or in aqueous micellar solutions. At pH 7.0 the rate constants are ca. 10(6) M-1 sec-1 for urate, alpha-tocopherol, and PUFA, and 6 X 10(7) M-1 sec-1 for ascorbate. When ozone-containing air is breathed, ascorbate in the lung may undergo direct ozonation. However, alpha-tocopherol is probably spared direct reaction with ozone because it doesn't effectively compete with PUFA in pulmonary membranes; rather, tocopherol is used to scavenge radicals produced from the ozone-PUFA reaction.

Effects of salinity and ascorbic acid on growth, water status and antioxidant system in a perennial halophyte

PubMed Central

Hameed, Abdul; Gulzar, Salman; Aziz, Irfan; Hussain, Tabassum; Gul, Bilquees; Khan, M. Ajmal

2015-01-01

Salinity causes oxidative stress in plants by enhancing production of reactive oxygen species, so that an efficient antioxidant system, of which ascorbic acid (AsA) is a key component, is an essential requirement of tolerance. However, antioxidant responses of plants to salinity vary considerably among species. Limonium stocksii is a sub-tropical halophyte found in the coastal marshes from Gujarat (India) to Karachi (Pakistan) but little information exists on its salt resistance. In order to investigate the role of AsA in tolerance, 2-month-old plants were treated with 0 (control), 300 (moderate) and 600 (high) mM NaCl for 30 days with or without exogenous application of AsA (20 mM) or distilled water. Shoot growth of unsprayed plants at moderate salinity was similar to that of controls while at high salinity growth was inhibited substantially. Sap osmolality, AsA concentrations and activities of AsA-dependant antioxidant enzymes increased with increasing salinity. Water spray resulted in some improvement in growth, indicating that the growth promotion by exogenous treatments could partly be attributed to water. However, exogenous application of AsA on plants grown under saline conditions improved growth and AsA dependent antioxidant enzymes more than the water control treatment. Our data show that AsA-dependent antioxidant enzymes play an important role in salinity tolerance of L. stocksii. PMID:25603966

In vitro and in vivo antioxidant activities of the aqueous extract of Celosia argentea leaves

PubMed Central

Malomo, S. O.; Ore, A.; Yakubu, M. T.

2011-01-01

Objective: The aqueous extract of Celosia argentea var. cristata L. leaves at 100, 200, and 400 mg/kg body weight (b.w.) was investigated against cadmium (Cd)-induced oxidative stress in Wistar rats. The in vitro antioxidant of the extract was evaluated using ammonium thiocyanate, reducing power, and membrane stabilizing models. Materials and Methods: For the in vivo study, 30 male rats (Rattus norvegicus) weighing 138.02 ± 7.02 g were completely randomized into 6 groups (A–F) of 5 animals each. Animals in groups A and B received 0.5 ml of distilled water and the same volume containing 8 mg/kg b.w. of Cd, respectively, for 7 days orally. Animals in groups C, D, E, and F were treated like those in group B except that they received 100 mg/kg b.w. of ascorbic acid, and 100, 200, and 400 mg/kg b.w. of the extract, respectively, in addition to Cd. Results: Phytochemical screening revealed the presence of alkaloids (0.61%), saponins (2.93%), cardiac glycosides (0.21%), cardenolides (0.20%), phenolics (3.26%), and flavonoids (2.38%). A total of 10 mg/ml of the extract inhibited linoleic acid oxidation by 67.57%. The highest reducing power was 100 mg/ml as against 10 mg/ml for ascorbic acid. In addition, 2 mg/ml of the extract produced a membrane stabilizing activity of 63.49% as against 77.46% for indomethacin. Compared with the distilled water control group, the administration of Cd alone significantly (P < 0.05) decreased the alkaline phosphatase activity of the rat liver and brain. This decrease was accompanied by a corresponding increase in the serum enzyme. The simultaneous administration of the extract and Cd produced an enzyme activity that compared favorably (P > 0.05) with the animals that received Cd and ascorbic acid. In addition, the reduction in the superoxide dismutase and catalase activity of the liver and brain of the animals, serum uric acid, albumin and bilirubin, and also the increase in the serum malondialdehyde content in animals treated with Cd alone was attenuated by the extract; the values compared well (P > 0.05) with those simultaneously administered with Cd and ascorbic acid. Conclusion: Overall, the results indicated that the aqueous extract of C. argentea leaves attenuated Cd-induced oxidative stress in the animals, with the best result at 400 mg/kg b.w. The antioxidant activity of the extract may be attributed to the phenolic and flavonoid components of the extract. The induction of antioxidant enzymes and scavenging of free radicals may account for the mechanism of action of the extract as an antioxidant. PMID:21713091

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

PubMed

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

2015-02-01

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

Antioxidative characteristics and inhibition of alpha-melanocyte-stimulating hormone-stimulated melanogenesis of vanillin and vanillic acid from Origanum vulgare.

PubMed

Chou, Tzung-Han; Ding, Hsiou-Yu; Hung, Wei Jing; Liang, Chia-Hua

2010-08-01

The antioxidant activities of vanillin and vanillic acid isolated from Origanum vulgare are investigated. These compounds may serve as agents for antimelanogenesis. Vanillic acid is a stronger antioxidant than vanillin, in terms of free radical scavenging activity, reducing power and inhibition of lipid peroxidation. The inhibition of cellular reactive oxygen species (ROS) in H(2)O(2)-treated BNLCL2 cells by vanillic acid exceeds that of ascorbic acid (AA) or trolox. In B16F0 cells stimulated with alpha-melanocyte-stimulating hormone (alpha-MSH), vanillic acid reduced cellular tyrosinase activity, DOPA oxidase and melanin contents, as well as down-regulated expressions of melanocortin-1 receptor (MC1R), microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related proteins 2 (TRP-2) and TRP-1. Vanillin did not express inhibition of tyrosinase activity. These results supported that vanillic acid is a significantly stronger antioxidant than vanillin and exhibited stronger antimelanogenesis performance because of the structural presence of the carboxyl group.

Antioxidant and anticholinesterase activities of five wild mushroom species with total bioactive contents.

PubMed

Tel, Gulsen; Ozturk, Mehmet; Duru, Mehmet E; Turkoglu, Aziz

2015-06-01

Recently, mushrooms are interesting natural products to be investigated due to exhibiting various bioactivities. This study determines the antioxidant and anticholinesterase activities of various extracts of five wild mushroom species. In addition, the total bioactive contents, namely, ascorbic acid, β-carotene, and lycopene along with phenolic and flavonoid contents were also determined spectrophotometrically. Antioxidant activity was tested by using five complementary tests; namely, β-carotene-linoleic acid, DPPH(•) scavenging, ABTS(•+) scavenging, cupric-reducing antioxidant capacity (CUPRAC), and metal chelating assays. The in vitro anticholinesterase activity was tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes using the Ellman method. The spectrophotometric methods were used to determine the total phenolic, flavonoid, ascorbic acid, β-carotene, and lycopene contents. The current study has shown that ethyl acetate extracts of Ganoderma lucidum (Curtis) P. Karst (IC50: 1.55 ± 0.05 µg/mL) and Funalia trogii (Berk.) Bondartsev & Singer (IC50: 4.31 ± 0.18 µg/mL) exhibited good lipid peroxidation inhibitory activity. The DPPH, ABTS, and CUPRAC assays supported this activity. The ethyl acetate and methanol extracts of Funalia trogii and Ganoderma lucidum indicated good anticholinesterase activity. Ganoderma lucidum had rich phenolic and flavonoid contents, indicating 98.67 ± 0.32 mg PEs/g extract and 160.38 ± 1.25 mg QEs/g extract, respectively. The results demonstrate that some of the mushroom species tested herein could be used in food and pharmaceutical industries as natural antioxidants.

Antioxidant effects of soy sauce on color stability and lipid oxidation of raw beef patties during cold storage.

PubMed

Kim, Hyun-Wook; Choi, Yun-Sang; Choi, Ji-Hun; Kim, Hack-Youn; Hwang, Ko-Eun; Song, Dong-Heon; Lee, Soo-Yoen; Lee, Mi-Ai; Kim, Cheon-Jei

2013-11-01

This study was conducted to evaluate the antioxidant effects of soy sauce on lipid oxidation and color stability of raw beef patties. Raw beef patties were formulated with four solutions such as NaCl (sodium chloride solution), NaCl/SS (1:1 ratio of sodium chloride and soy sauce solution), SS (soy sauce solution), or SS/A (soy sauce solution combined with 0.05% ascorbic acid) in the same salt concentration. Addition of soy sauce resulted in the decreased pH, lightness, and increased yellowness. Treatment SS/A had the lowest percent of metmyoglobin during storage (P<0.05). A reduction (P<0.05) in the 2-thiobarbituric acid, peroxide, and conjugated diene concentration as result of soy sauce addition were observed in treatments SS and SS/A at the end of the storage period. There were no differences (P>0.05) in free fatty acid concentration at the end of storage. The combined addition of soy sauce and ascorbic acid greatly improved (P<0.05) color stability and retarded lipid oxidation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Ripening of Pithecellobium dulce (Roxb.) Benth. [Guamúchil] Fruit: Physicochemical, Chemical and Antioxidant Changes.

PubMed

Wall-Medrano, Abraham; González-Aguilar, Gustavo A; Loarca-Piña, Guadalupe F; López-Díaz, José A; Villegas-Ochoa, Mónica A; Tortoledo-Ortiz, Orlando; Olivas-Aguirre, Francisco J; Ramos-Jiménez, Arnulfo; Robles-Zepeda, Ramón

2016-12-01

The fruit of Guamúchil is an excellent source of bioactive compounds for human health although their natural occurrence could be affected by the ripening process. The aim was to evaluate some physicochemical, chemical and antioxidant changes in guamúchil fruit during six ripening stages (I to VI). A defined trend (p ≤ 0.003) was observed for color [°Hue, 109 (light green) to 20 (dark red)], anthocyanins (+571 %), soluble solids (+0.33 o Brix), ash (+16 %), sucrose (-91 %), proanthocyanidins (63 %), ascorbic acid (-52 %) and hydrolysable PC (-21 %). Carotenoids were not detected and chlorogenic acid was the most abundant phenolic compound. Maximal availability of these bioactives per ripening stage (p ≤ 0.03) was as follows: I (protein/ lipids/ sucrose/ proanthocyanidins/ hydrolysable phenolics), II (total sugars/ascorbic acid), III (total phenolics), IV (flavonoids/ chlorogenic acid) and VI (fructose/ glucose/ anthocyanins). Color change was explained by sucrose (β = 0.47) and anthocyanin (β = 0.20) contents (p < 0.001). Radical scavenging capacity (ORAC, DPPH and TEAC) strongly correlated with total PC (r = 0.49-0.65, p ≤ 0.001) but 89 % of ORAC's associated variance was explained by anthocyanin + sucrose + ascorbic acid (p ≤ 0.0001). Guamúchil fruit could be a more convenient source of specific bioactive compounds if harvested at different ripening stages.

Wheat bran particle size influence on phytochemical extractability and antioxidant properties.

PubMed

Brewer, Lauren Renee; Kubola, Jittawan; Siriamornpun, Sirithon; Herald, Thomas J; Shi, Yong-Cheng

2014-01-01

It is unknown if particle size plays a role in extracting health promoting compounds in wheat bran because the extraction of antioxidant and phenolic compounds with particle size reduction has not been well documented. In this study, unmilled whole bran (coarse treatment) was compared to whole bran milled to medium and fine treatments from the same wheat bran. Antioxidant properties (capacity, ability, power), carotenoids and phenolic compounds (phenolic acids, flavonoids, anthocyanins) were measured and compared. The ability of whole bran fractions of differing particle size distributions to inhibit free radicals was assessed using four in vitro models, namely, diphenylpicrylhydrazyl radical-scavenging activity, ferric reducing/antioxidant power (FRAP) assay, oxygen radical absorbance capacity (ORAC), and total antioxidant capacity. Significant differences in phytochemical concentrations and antioxidant properties were observed between whole bran fractions of reduced particle size distribution for some assays. The coarse treatment exhibited significantly higher antioxidant properties compared to the fine treatment; except for the ORAC value, in which coarse was significantly lower. For soluble and bound extractions, the coarse treatment was comparatively higher in total antioxidant capacity (426.72 mg ascorbic acid eq./g) and FRAP value (53.04 μmol FeSO4/g) than bran milled to the finer treatment (314.55 ascorbic acid eq./g and 40.84 μmol FeSO4/g, respectively). Likewise, the fine treatment was higher in phenolic acid (7.36 mg FAE/g), flavonoid (206.74 μg catechin/g), anthocyanin (63.0 μg/g), and carotenoid contents (beta carotene, 14.25 μg/100 g; zeaxanthin, 35.21 μg/100 g; lutein 174.59 μg/100 g) as compared to the coarse treatment. An increase of surface area to mass increased the ORAC value by over 80%. With reduction in particle size, there was a significant increase in extracted anthocyanins, carotenoids and ORAC value. Particle size does effect the extraction of phytochemicals. Copyright © 2013 Elsevier Ltd. All rights reserved.

Characterization of phenolics, glucosinolates and antioxidant activity of beverages based on apple juice with addition of frozen and freeze-dried curly kale leaves (Brassica oleracea L. var. acephala L.).

PubMed

Biegańska-Marecik, Róża; Radziejewska-Kubzdela, Elżbieta; Marecik, Roman

2017-09-01

The aim of this study was to determine the polyphenols, glucosinolates and ascorbic acid content as well as antioxidant activity of beverages on the base of apple juice with addition of frozen and freeze-dried curly kale leaves. Upon enrichment with frozen (13%) and freeze-dried curly kale (3%), the naturally cloudy apple juice was characterized by an increase in phenolic compounds by 2.7 and 3.3-times, accordingly. The antioxidant activity of beverages with the addition of curly kale ranged from 6.6 to 9.4μmol Trolox/mL. The obtained beverages were characterized glucosinolates content at 117.6-167.6mg/L and ascorbic acid content at 4,1-31,9mg/L. The results of sensory evaluation of colour, taste and consistency of apple juice and beverages with the addition of kale did not differ significantly prior to pasteurization (P≤0.05), whereas after the pasteurization the evaluated factors decreased significantly. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

PubMed

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

2005-12-01

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

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

Ames, B.N.; Cathcart, R.; Schwiers, E.

During primate evolution, a major factor in lengthening life-span and decreasing age-specific cancer rates may have been improved protective mechanisms against oxygen radicals. We propose that one of these protective systems is plasma uric acid, the level of which increased markedly during primate evolution as a consequence of a series of mutations. Uric acid is a powerful antioxidant and is a scavenger of singlet oxygen and radicals. We show that, at physiological concentrations, urate reduces the oxo-heme oxidant formed by peroxide reaction with hemoglobin, protects erythrocyte ghosts against lipid peroxidation, and protects erythrocytes from peroxidative damage leading to lysis. Uratemore » is about as effective an antioxidant as ascorbate in these experiments. Urate is much more easily oxidized than deoxynucleosides by singlet oxygen and is destroyed by hydroxyl radicals at a comparable rate. The plasma urate level in humans (about 300 ..mu..M) is considerably higher than the ascorbate level, making it one of the major antioxidants in humans. Previous work on urate reported in the literature supports our experiments and interpretations, although the findings were not discussed in a physiological context.« less

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

PubMed

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

2001-07-01

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

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

PubMed

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

2014-01-01

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

Supplementation with lutein or lutein plus green tea extracts does not change oxidative stress in adequately nourished older adults1

PubMed Central

Li, Lei; Chen, C-Y. Oliver; Aldini, Giancarlo; Johnson, Elizabeth J; Rasmussen, Helen; Yoshida, Yasukazu; Niki, Etsuo; Blumberg, Jeffrey B; Russell, Robert M.; Yeum, Kyung-Jin

2009-01-01

Epigallocatechin gallate, a major component of green tea polyphenols, protects against the oxidation of fat-soluble antioxidants including lutein. The current study determined the effect of relatively high but a dietary achievable dose of lutein or lutein plus green tea extract on antioxidant status. Healthy subjects (50–70 yrs) were randomly assigned to one of 2 groups, (n=20 in each group) 1) a lutein (12mg/d) supplemented group, or 2) a lutein (12 mg/d) plus green tea extract (200 mg/d) supplemented group. After 2 wks of run-in period consumed less than two servings of lightly-colored fruit & vegetables in their diet, each group was treated for 112 days while on their customary regular diets. Plasma carotenoids including lutein, tocopherols, flavanols and ascorbic acid were analyzed by HPLC-UVD and -ECD systems; total antioxidant capacity by fluorometry; lipid peroxidation by malondialdehyde using a HPLC system with a fluorescent detector and by total hydroxyoctadecadienoic acids using a GC/MS. Plasma lutein, total carotenoids and ascorbic acid concentrations of subjects in either lutein group or lutein plus green tea extract group were significantly increased (p<0.05) at 4 wks and throughout the 16 wks study period. However, no significant changes from baseline in any biomarker of overall antioxidant activity or lipid peroxidation of the subjects were seen in either group. Our results indicate that an increase of antioxidant concentrations within a range that could readily be achieved in a healthful diet does not affect in vivo antioxidant status in normal healthy subjects when sufficient amounts of antioxidants already exist. PMID:19447020

Effect of different antioxidant additives in semen diluent on cryopreservability (-196°C) of buffalo semen.

PubMed

Patel, Hardik A; Siddiquee, G M; Chaudhari, Dinesh V; Suthar, Vishal S

2016-03-01

The aim of this study was to evaluate the effect of different antioxidant additives in standard tris-fructose-egg yolk-glycerol (TFYG) extender on the cryopreservability of buffalo semen. Semen collection using artificial vagina, twice weekly for 5 weeks from three pedigreed health breeding bulls of Mehsani breed, aged between 6 and 8 years. Immediately after initial evaluation all 30 qualifying ejaculates (10/bull) were split into three aliquots and diluted at 34°C keeping the concentration of 100 million spermatozoa/ml with standard TFYG extender as control and TFYG having two antioxidant additives - Cysteine HCl at 1 mg/ml and ascorbic acid at 0.2 mg/ml to study their comparative performance. Semen filled in French Mini straws using IS-4 system and gradually cooled to 4°C and equilibrated for 4 h in cold handing cabinet. After completion of equilibration, straws were cryopreserved in LN2 by Programmable Bio-freezer. Semen was examined at post-dilution, post-equilibration, and post-thaw stages for sperm quality parameters, and at each stage plasma was separated for enzymatic analysis of aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and alkaline phosphatase (AKP). The mean percentage of sperms in TFYG, TFYG + cysteine HCl and TFYG + ascorbic acid diluents at post-thaw stage in terms of progressive motility (52.83±0.52, 57.83±0.52, 57.83±0.52), livability (78.70±0.21, 82.33±0.23, 81.73±0.22), and abnormality (5.43±0.21, 5.03±0.17, 5.23±0.18) varied significantly (p<0.05) between control TFYG and TFYG having antioxidant additives. The mean U/L activities of AST (78.70±0.47, 72.80±0.48, 73.30±0.54), LDH (172.70±0.41, 155.78±0.42, 156.33±0.41), and AKP (103.61±0.34, 90.20±0.34, 91.03±0.34) in semen diluted with TFYG, TFYG + cysteine HCl and TFYG + ascorbic acid diluents at post-thaw stage, respectively, which showed significantly (p<0.05) higher leakage of enzymes in control TFYG than TFYG incorporated with additives. Incorporation of antioxidant additives such as cysteine HCl and ascorbic acid in standard TFYG diluents improves sperm quality parameters, reduces enzyme leakage, and ultimately advances cryopreservability of buffalo semen.

The toxicity of N-methyl-alpha-methyldopamine to freshly isolated rat hepatocytes is prevented by ascorbic acid and N-acetylcysteine.

PubMed

Carvalho, Márcia; Remião, Fernando; Milhazes, Nuno; Borges, Fernanda; Fernandes, Eduarda; Carvalho, Félix; Bastos, Maria Lourdes

2004-08-05

In the past decade, clinical evidence has increasingly shown that the liver is a target organ for 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") toxicity. The aims of the present in vitro study were: (1) to evaluate and compare the hepatotoxic effects of MDMA and one of its main metabolites, N-methyl-alpha-methyldopamine (N-Me-alpha-MeDA) and (2) to investigate the ability of antioxidants, namely ascorbic acid and N-acetyl-L-cysteine (NAC), to prevent N-Me-alpha-MeDA-induced toxic injury, using freshly isolated rat hepatocytes. Cell suspensions were incubated with MDMA or N-Me-alpha-MeDA in the final concentrations of 0.1, 0.2, 0.4, 0.8, and 1.6 mM for 3 h. To evaluate the potential protective effects of antioxidants, cells were preincubated with ascorbic acid in the final concentrations of 0.1 and 0.5 mM, or NAC in the final concentrations of 0.1 and 1 mM for 15 min before treatment with 1.6 mM N-Me-alpha-MeDA for 3 h (throughout this incubation period the cells were exposed to both compounds). The toxic effects were evaluated by measuring the cell viability, glutathione (GSH) and glutathione disulfide (GSSG), ATP, and the cellular activities of GSH peroxidase (GPX), GSSG reductase (GR), and GSH S-transferase (GST). MDMA induced a concentration- and time-dependent GSH depletion, but had a negligible effect on cell viability, ATP levels, or on the activities of GR, GPX, and GST. In contrast, N-Me-alpha-MeDA was shown to induce not only a concentration- and time-dependent depletion of GSH, but also a depletion of ATP levels accompanied by a loss in cell viability, and decreases in the antioxidant enzyme activities. For both compounds, GSH depletion was not accompanied by increases in GSSG levels, which seems to indicate GSH depletion by adduct formation. Importantly, the presence of ascorbic acid (0.5 mM) or NAC (1 mM) prevented cell death and GSH depletion induced by N-Me-alpha-MeDA. The results provide evidence that MDMA and its metabolite N-Me-alpha-MeDA induce toxicity to freshly isolated rat hepatocytes. Oxidative stress may play a major role in N-Me-alpha-MeDA-induced hepatic toxicity since antioxidant defense systems are impaired and administration of antioxidants prevented N-Me-alpha-MeDA toxicity.

Extracellular micronutrient levels and pro-/antioxidant status in trauma patients with wound healing disorders: results of a cross-sectional study.

PubMed

Blass, Sandra C; Goost, Hans; Burger, Christof; Tolba, René H; Stoffel-Wagner, Birgit; Stehle, Peter; Ellinger, Sabine

2013-12-05

Disorders in wound healing (DWH) are common in trauma patients, the reasons being not completely understood. Inadequate nutritional status may favor DWH, partly by means of oxidative stress. Reliable data, however, are lacking. This study should investigate the status of extracellular micronutrients in patients with DWH within routine setting. Within a cross-sectional study, the plasma/serum status of several micronutrients (retinol, ascorbic acid, 25-hydroxycholecalciferol, α-tocopherol, β-carotene, selenium, and zinc) were determined in 44 trauma patients with DWH in addition to selected proteins (albumin, prealbumin, and C-reactive protein; CRP) and markers of pro-/antioxidant balance (antioxidant capacity, peroxides, and malondialdehyde). Values were compared to reference values to calculate the prevalence for biochemical deficiency. Correlations between CRP, albumin and prealbumin, and selected micronutrients were analyzed by Pearson's test. Statistical significance was set at P < 0.05. Mean concentrations of ascorbic acid (23.1 ± 15.9 μmol/L), 25-hydroxycholecalciferol (46.2±30.6 nmol/L), β-carotene (0.6 ± 0.4 μmol/L), selenium (0.79±0.19 μmol/L), and prealbumin (24.8 ± 8.2 mg/dL) were relatively low. Most patients showed levels of ascorbic acid (<28 μmol/L; 64%), 25-hydroxycholecalciferol (<50 μmol/L; 59%), selenium (≤ 94 μmol/L; 71%) and β-carotene (<0.9 μmol/L; 86%) below the reference range. Albumin and prealbumin were in the lower normal range and CRP was mostly above the reference range. Plasma antioxidant capacity was decreased, whereas peroxides and malondialdehyde were increased compared to normal values. Inverse correlations were found between CRP and albumin (P < 0.05) and between CRP and prealbumin (P < 0.01). Retinol (P < 0.001), ascorbic acid (P < 0.01), zinc (P < 0.001), and selenium (P < 0.001) were negatively correlated with CRP. Trauma patients with DWH frequently suffer from protein malnutrition and reduced plasma concentrations of several micronutrients probably due to inflammation, increased requirement, and oxidative burden. Thus, adequate nutritional measures are strongly recommended to trauma patients.

Vitamin C acts as radiation-protecting agent

NASA Astrophysics Data System (ADS)

Platzer, Isabel; Getoff, Nikola

1998-01-01

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

Primary, Secondary Metabolites, Photosynthetic Capacity and Antioxidant Activity of the Malaysian Herb Kacip Fatimah (Labisia Pumila Benth) Exposed to Potassium Fertilization under Greenhouse Conditions

PubMed Central

Ibrahim, Mohd Hafiz; Jaafar, Hawa Z. E.; Karimi, Ehsan; Ghasemzadeh, Ali

2012-01-01

A randomized complete block design was used to characterize the relationship between production of total phenolics, flavonoids, ascorbic acid, carbohydrate content, leaf gas exchange, phenylalanine ammonia-lyase (PAL), soluble protein, invertase and antioxidant enzyme activities (ascorbate peroxidase (APX), catalase (CAT) and superoxide dismutase (SOD) in Labisia pumila Benth var. alata under four levels of potassium fertilization experiments (0, 90, 180 and 270 kg K/ha) conducted for 12 weeks. It was found that the production of total phenolics, flavonoids, ascorbic acid and carbohydrate content was affected by the interaction between potassium fertilization and plant parts. As the potassium fertilization levels increased from 0 to 270 kg K/ha, the production of soluble protein and PAL activity increased steadily. At the highest potassium fertilization (270 kg K/ha) L. pumila exhibited significantly higher net photosynthesis (A), stomatal conductance (gs), intercellular CO2 (Ci), apparent quantum yield (ξ) and lower dark respiration rates (Rd), compared to the other treatments. It was found that the production of total phenolics, flavonoids and ascorbic acid are also higher under 270 kg K/ha compared to 180, 90 and 0 kg K/ha. Furthermore, from the present study, the invertase activity was also found to be higher in 270 kg K/ha treatment. The antioxidant enzyme activities (APX, CAT and SOD) were lower under high potassium fertilization (270 kg K/ha) and have a significant negative correlation with total phenolics and flavonoid production. From this study, it was observed that the up-regulation of leaf gas exchange and downregulation of APX, CAT and SOD activities under high supplementation of potassium fertilizer enhanced the carbohydrate content that simultaneously increased the production of L. pumila secondary metabolites, thus increasing the health promoting effects of this plant. PMID:23203128

Advances in the analytical methods for determining the antioxidant properties of honey: a review.

PubMed

Moniruzzaman, M; Khalil, M I; Sulaiman, S A; Gan, S H

2012-01-01

Free radicals and reactive oxygen species (ROS) have been implicated in contributing to the processes of aging and disease. In an effort to combat free radical activity, scientists are studying the effects of increasing individuals' antioxidant levels through diet and dietary supplements. Honey appears to act as an antioxidant in more ways than one. In the body, honey can mop up free radicals and contribute to better health. Various antioxidant activity methods have been used to measure and compare the antioxidant activity of honey. In recent years, DPPH (Diphenyl-1-picrylhydrazyl), FRAP (Ferric Reducing Antioxidant Power), ORAC (The Oxygen Radical Absorbance Capacity), ABTS [2, 2-azinobis (3ehtylbenzothiazoline-6-sulfonic acid) diamonium salt], TEAC [6-hydroxy-2, 5, 7, 8-tetramethylchroman-2-carboxylic acid (Trolox)-equivalent antioxidant capacity] assays have been used to evaluate antioxidant activity of honey. The antioxidant activity of honey is also measured by ascorbic acid content and different enzyme assays like Catalase (CAT), Glutathione Peroxidase (GPO), Superoxide Dismutase (SOD). Among the different methods available, methods that have been validated, standardized and widely reported are recommended.

Effect of added sugar and ascorbic acid on the anthocyanin content of high pressure processed strawberry juices during storage

NASA Astrophysics Data System (ADS)

Salamon, B.; Farkas, V.; Kenesei, Gy; Dalmadi, I.

2017-10-01

Berries have high nutritional value and can be processed in many kinds of ways. Their pigments (anthocyanins, flavonoids, carotenoids) have antioxidant properties, effectively neutralize the health-damaging free radicals. High hydrostatic pressure (HHP) technology is a minimal processing technique which is a promising alternative solution instead of traditional preservation technologies. Low molecular weight materials such as colour pigments are well preserved by application of HHP. However, the effect can be influenced by the composition of the treated food matrix. The available scientific information related to the impact of sugar and ascorbic acid content on the preservation of anthocyanins in the samples is controversial. Thus, the aim of our study was to determine the effect of HHP treatment parameters (pressure, treatment time) on the preservation of the anthocyanin content of strawberry juice supplemented by different amounts of sugar and ascorbic acid. 2n type factorial experimental design was used to evaluate the effect of four factors (refraction index, ascorbic acid, pressure, treatment time) on the residual content of total anthocyanins immediately after HHP treatment and after 21 days storage at room temperature.

Involvement of polyamine oxidase in abscisic acid-induced cytosolic antioxidant defense in leaves of maize.

PubMed

Xue, Beibei; Zhang, Aying; Jiang, Mingyi

2009-03-01

Using pharmacological and biochemical approaches, the role of maize polyamine oxidase (MPAO) in abscisic acid (ABA)-induced antioxidant defense in leaves of maize (Zea mays L.) plants was investigated. Exogenous ABA treatment enhanced the expression of the MPAO gene and the activities of apoplastic MPAO. Pretreatment with two different inhibitors for apoplastic MPAO partly reduced hydrogen peroxide (H2O2) accumulation induced by ABA and blocked the ABA-induced expression of the antioxidant genes superoxide dismutase 4 and cytosolic ascorbate peroxidase and the activities of the cytosolic antioxidant enzymes. Treatment with spermidine, the optimum substrate of MPAO, also induced the expression and the activities of the antioxidant enzymes, and the upregulation of the antioxidant enzymes was prevented by two inhibitors of MPAO and two scavengers of H2O2. These results suggest that MPAO contributes to ABA-induced cytosolic antioxidant defense through H2O2, a Spd catabolic product.

Total antioxidant and ascorbic acid content of fresh fruits and vegetables: implications for dietary planning and food preservation.

PubMed

Szeto, Yim Tong; Tomlinson, Brian; Benzie, Iris F F

2002-01-01

Epidemiological evidence links high intake of ascorbic acid (AA) and other antioxidant micronutrients to health promotion. It would be useful to know the overall, or 'total' antioxidant capacity of foods, to establish the contribution of AA to this, and to assess how this information may translate into dietary intakes to meet the new US daily reference intake for AA. In this study, the total antioxidant capacity, as the ferric reducing-antioxidant power (FRAP) value, and AA content of thirty-four types of fruits and vegetables were measured using a modified version of the FRAP assay, known as FRASC. This measures AA (reduced form only) simultaneously with the FRAP value. Results covered a wide range: 880-15940 micromol/kg fresh wet weight and <20-540 mg/kg fresh wet weight respectively, for FRAP and AA, which comprised < 1-73 % and < 1-59 % total antioxidant capacity of fruits and vegetables respectively. We estimate that 100 mg AA is contained in one orange, a few strawberries, one kiwi fruit, 1-2 slices of pineapple, several florets of raw cauliflower or a handful of uncooked spinach leaves. Apples, bananas, pears and plums, the most commonly consumed fruits in the UK, contain very little AA. Results indicate also that the antioxidant capacity of vegetables decreases rapidly and significantly after fragmentation. Results of this, and future studies, using FRASC as a biomonitoring tool will be useful in food production, preparation, preservation, and aid dietary choices to increase antioxidant and AA intake. Furthermore, FRASC will facilitate bioavailability studies of antioxidants from different foods of known antioxidant capacity and AA content.

Ascorbic Acid-A Potential Oxidant Scavenger and Its Role in Plant Development and Abiotic Stress Tolerance

PubMed Central

Akram, Nudrat A.; Shafiq, Fahad; Ashraf, Muhammad

2017-01-01

Over-production of reactive oxygen species (ROS) in plants under stress conditions is a common phenomenon. Plants tend to counter this problem through their ability to synthesize ROS neutralizing substances including non-enzymatic and enzymatic antioxidants. In this context, ascorbic acid (AsA) is one of the universal non-enzymatic antioxidants having substantial potential of not only scavenging ROS, but also modulating a number of fundamental functions in plants both under stress and non-stress conditions. In the present review, the role of AsA, its biosynthesis, and cross-talk with different hormones have been discussed comprehensively. Furthermore, the possible involvement of AsA-hormone crosstalk in the regulation of several key physiological and biochemical processes like seed germination, photosynthesis, floral induction, fruit expansion, ROS regulation and senescence has also been described. A simplified and schematic AsA biosynthetic pathway has been drawn, which reflects key intermediates involved therein. This could pave the way for future research to elucidate the modulation of plant AsA biosynthesis and subsequent responses to environmental stresses. Apart from discussing the role of different ascorbate peroxidase isoforms, the comparative role of two key enzymes, ascorbate peroxidase (APX) and ascorbate oxidase (AO) involved in AsA metabolism in plant cell apoplast is also discussed particularly focusing on oxidative stress perception and amplification. Limited progress has been made so far in terms of developing transgenics which could over-produce AsA. The prospects of generation of transgenics overexpressing AsA related genes and exogenous application of AsA have been discussed at length in the review. PMID:28491070

Treatment of Pancreatic Cancer with Pharmacological Ascorbate

PubMed Central

Cieslak, John A.; Cullen, Joseph J.

2016-01-01

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

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

PubMed Central

Harrison, Fiona E.; May, James M.

2009-01-01

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

HPLC profiling, antioxidant and in vivo anti-inflammatory activity of the ethanol extract of Syzygium jambos available in Bangladesh.

PubMed

Hossain, Hemayet; Rahman, Shaikh Emdadur; Akbar, Proity Nayeeb; Khan, Tanzir Ahmed; Rahman, Md Mahfuzur; Jahan, Ismet Ara

2016-03-28

Syzygium jambos has been used as a traditional medicine for the treatment of inflammatory diseases in Bangladesh. The study investigates the high performance liquid chromatography (HPLC) profiling of phenolic compounds, and evaluates the antioxidant and anti-inflammatory activities of ethanol extract of S. jambos available in Bangladesh. The extract was subjected to HPLC for the identification and quantification of the major bioactive polyphenols present in S. jambos. Antioxidant activity was determined using 2, 2'-azino bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging, reducing power assay, total antioxidant capacity, total phenolic and flavonoid content. Furthermore, the anti-inflammatory effect of the extract in rats for two different test models: carrageenan and histamine-induced paw edema was inspected. High levels of catechin hydrate and rutin hydrate (99.00 and 79.20 mg/100 g extract, respectively) and moderate amounts of ellagic acid and quercetin (59.40 and 69.30 mg/100 g extract, respectively) were quantified in HPLC. Catechin hydrate from this plant extract was determined for the first time through HPLC. For ABTS scavenging assay, the median inhibition concentration (IC50) value of S. jambos was 57.80 µg/ml, which was significant to that of ascorbic acid (12.01 µg/ml). The maximum absorbance for reducing power assay was found to be 0.4934. The total antioxidant capacity, phenolic and flavonoid contents were calculated to be 628.50 mg/g of ascorbic acid, 230.82 mg/g of gallic acid and 11.84 mg/g of quercetin equivalent, respectively. At a dose of 400 mg/kg, a significant acute anti-inflammatory activity (P < 0.01) was observed in rats for both the test models with a reduction in the paw volume of 58.04 and 53.95 %, in comparison to those of indomethacin (62.94 and 65.79 %), respectively. The results suggest that the phenolic and flavonoid compounds are responsible for acute anti-inflammatory and antioxidant activities of S. jambos.

Investigation of antioxidant properties of metal ascorbates and their mixtures by voltammetry

NASA Astrophysics Data System (ADS)

Vtorushina, A. N.; Nikonova, E. D.

2015-04-01

The paper describes modern ways for selection of anti-radical substances. Molding of such components with a carbon-based material decreases the rate of its oxidative destruction. Addition of such a component to a carbon-based material decreases the rate of its oxidative destruction. The purpose of this study is to determine the antioxidant activity of ascorbates metals (Ca, Mg, Li, Co, Fe), used in the practice of medicine, as well as mixtures based on them together with well-known antioxidants. In this article we examine the effect of metals on the process of ascorbate oxygen electroreduction. From these ascorbates lithium and magnesium ascorbate showed the greatest activity toward cathode oxygen reduction process. Also mixtures with well-known examined antioxidants ascorbate (glucose, dihydroquercetin) were investigated at different concentrations of components. It is shown that the multicomponent mixtures exhibit lower activity than the individual drugs. Recommended the creation of drugs on the basis of ascorbate Mg and Li with not more than 3 number of components.

Determination of total antioxidant capacity by a new spectrofluorometric method based on Ce(IV) reduction: Ce(III) fluorescence probe for CERAC assay.

PubMed

Ozyurt, Dilek; Demirata, Birsen; Apak, Resat

2011-11-01

A Ce(IV)-based reducing capacity (CERAC) assay was developed to measure the total antioxidant capacity (TAC) of foods, in which Ce(IV) would selectively oxidize antioxidant compounds but not citric acid and reducing sugars which are not classified as antioxidants. The method is based on the electron-transfer (ET) reaction between Ce(IV) ion and antioxidants in optimized acidic sulphate medium (i.e., 0.3 M H(2)SO(4) and 0.7 M Na(2)SO(4)) and subsequent determination of the produced Ce(III) ions by a fluorometric method. The fluorescent product, Ce(III), exhibited strong fluorescence at 360 nm with an excitation wavelength of 256 nm, the fluorescence intensity being correlated to antioxidant power of the original sample. The linear concentration range for most antioxidants was quite wide, e.g., 5.0 × 10(-7)-1.0 × 10(-5) M for quercetin. The developed procedure was successfully applied to the TAC assay of antioxidant compounds such as trolox, quercetin, gallic acid, ascorbic acid, catechin, naringin, naringenin, caffeic acid, ferulic acid, glutathione, and cysteine. The proposed method was reproducible, additive in terms of TAC values of constituents of complex mixtures, and the trolox equivalent antioxidant capacities (TEAC coefficients) of the tested antioxidant compounds gave good correlations with those found by reference methods such as ABTS and CUPRAC.

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

PubMed

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

2009-01-01

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

Oxidative Stress and Antioxidants in Tomato (Solanum lycopersicum) Plants Subjected to Boron Toxicity

PubMed Central

Cervilla, Luis M.; Blasco, Begoña; Ríos, Juan J.; Romero, Luis; Ruiz, Juan M.

2007-01-01

Background and Aims Boron (B) toxicity triggers the formation of reactive oxygen species in plant tissues. However, there is still a lack of knowledge as to how B toxicity affects the plant antioxidant defence system. It has been suggested that ascorbate could be important against B stress, although existing information is limited in this respect. The objective of this study was to analyse how ascorbate and some other components of the antioxidant network respond to B toxicity. Methods Two tomato (Solanum lycopersicum) cultivars (‘Kosaco’ and ‘Josefina’) were subjected to 0·05 (control), 0·5 and 2 mm B. The following were studied in leaves: dry weight; relative leaf growth rate; total and free B; H2O2; malondialdehyde; ascorbate; glutathione; sugars; total non-enzymatic antioxidant activity, and the activity of superoxide dismutase, catalase, ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, glutathione reductase, ascorbate oxidase and l-galactose dehydrogenase. Key Results The B-toxicity treatments diminished growth and boosted the amount of B, malondialdehyde and H2O2 in the leaves of the two cultivars, these trends being more pronounced in ‘Josefina’ than in ‘Kosaco’. B toxicity increased ascorbate concentration in both cultivars and increased glutathione only in ‘Kosaco’. Activities of antioxidant- and ascorbate-metabolizing enzymes were also induced. Conclusions High B concentration in the culture medium provokes oxidative damage in tomato leaves and induces a general increase in antioxidant enzyme activity. In particular, B toxicity increased ascorbate pool size. It also increased the activity of l-galactose dehydrogenase, an enzyme involved in ascorbate biosynthesis, and the activity of enzymes of the Halliwell–Asada cycle. This work therefore provides a starting point towards a better understanding of the role of ascorbate in the plant response against B stress. PMID:17660516

Redox Signaling and CBF-Responsive Pathway Are Involved in Salicylic Acid-Improved Photosynthesis and Growth under Chilling Stress in Watermelon

PubMed Central

Cheng, Fei; Lu, Junyang; Gao, Min; Shi, Kai; Kong, Qiusheng; Huang, Yuan; Bie, Zhilong

2016-01-01

Salicylic acid (SA) plays an important role in plant response to abiotic stresses. This study investigated the potential role of SA in alleviating the adverse effects of chilling stress on photosynthesis and growth in watermelon (Citrullus lanatus). Chilling stress induced the simultaneous accumulation of free and conjugated SA in watermelon plants, and the chilling-induced SA production was attributed to the phenylalanine ammonia-lyase pathway. Applying SA at moderate concentrations induced chilling tolerance, whereas inhibition of SA biosynthesis by L-α-aminooxy-β-phenylpropionic acid (AOPP) increased the photooxidation of PS II under chilling stress in watermelon, resulting in reduced photosynthesis and growth. Chilling induced a transient increase in the ratios of reduced to oxidized glutathione and reduced ascorbate to dehydroascorbate. Then, the expression of antioxidant genes was upregulated, and the activities of antioxidant enzymes were enhanced. Furthermore, SA-induced chilling tolerance was associated with cellular glutathione and ascorbate homeostasis, which served as redox signals to regulate antioxidant metabolism under chilling stress. AOPP treatment stimulated the chilling-induced expression of cold-responsive genes, particularly via C-repeat binding factors CBF3 and CBF4. These results confirm the synergistic role of SA signaling and the CBF-dependent responsive pathway during chilling stress in watermelon. PMID:27777580

Erythrocyte antioxidant protection of rose hips (Rosa spp.).

PubMed

Widén, C; Ekholm, A; Coleman, M D; Renvert, S; Rumpunen, K

2012-01-01

Rose hips are popular in health promoting products as the fruits contain high content of bioactive compounds. The aim of this study was to investigate whether health benefits are attributable to ascorbic acid, phenols, or other rose-hip-derived compounds. Freeze-dried powder of rose hips was preextracted with metaphosphoric acid and the sample was then sequentially eluted on a C(18) column. The degree of amelioration of oxidative damage was determined in an erythrocyte in vitro bioassay by comparing the effects of a reducing agent on erythrocytes alone or on erythrocytes pretreated with berry extracts. The maximum protection against oxidative stress, 59.4 ± 4.0% (mean ± standard deviation), was achieved when incubating the cells with the first eluted meta-phosphoric extract. Removal of ascorbic acid from this extract increased the protection against oxidative stress to 67.9 ± 1.9%. The protection from the 20% and 100% methanol extracts was 20.8 ± 8.2% and 5.0 ± 3.2%, respectively. Antioxidant uptake was confirmed by measurement of catechin by HPLC-ESI-MS in the 20% methanol extract. The fact that all sequentially eluted extracts studied contributed to protective effects on the erythrocytes indicates that rose hips contain a promising level of clinically relevant antioxidant protection.

Influences of harvest date and location on the levels of ß-carotene, ascorbic acid, total phenols, in vitro antioxidant capacity, and phenolic profiles of five commercial varieties of mango (Mangifera indica L.)

USDA-ARS?s Scientific Manuscript database

Mango (Mangifera indica L.) is a tropical fruit crop grown worldwide with widely attributed nutritional and health-promoting properties. Extensive studies have been made of the high concentrations of phenolic antioxidants in the peel, seeds, and leaves of mango, yet less is known about the phenolic ...

Quantification of hexanal as an index of lipid oxidation in human milk and association with antioxidant components

PubMed Central

Elisia, Ingrid; Kitts, David D.

2011-01-01

Hexanal, a secondary product of lipid oxidation, was identified as the major volatile aldehyde generated from lipid peroxidation in human milk. Hexanal was quantified in human milk using solid phase microextraction-gas chromatography/flame ionization detection that required correction for recovery based on the fat content of human milk. Alpha-tocopherol was the only tocopherol isomer in human milk found to be significantly correlated with hexanal (R = −0.374, p<0.05) and the total antioxidant capacity of human milk (ORACFl (R = 0.408, p<0.01)). Ascorbic acid content was negatively correlated (R = −0.403, p<0.05) with hexanal, but not to ORACFl in human milk. The effect of Holder pasteurization on oxidative status of human milk was determined using multiple parameters that included, hexanal level and malondialdehyde as markers of lipid oxidation, vitamins C and E content and antioxidant capacity (e.g. ORACFl). Pasteurization did not affect the oxidative status of milk as measured by hexanal level, ORACFl and malondialdehyde content. We conclude that hexanal is a sensitive and useful chemical indicator for assessing peroxidation reactions in human milk and that alpha tocopherol and ascorbic acid are two key antioxidant components in milk that contribute to protection against oxidation of milk lipids. PMID:22128211

Reduction of hydrogen peroxide-induced erythrocyte damage by Carica papaya leaf extract

PubMed Central

Okoko, Tebekeme; Ere, Diepreye

2012-01-01

Objective To investigate the in vitro antioxidant potential of Carica papaya (C. papaya) leaf extract and its effect on hydrogen peroxide-induced erythrocyte damage assessed by haemolysis and lipid peroxidation. Methods Hydroxyl radical scavenging activities, hydrogen ion scavenging activity, metal chelating activity, and the ferrous ion reducing ability were assessed as antioxidant indices. In the other experiment, human erythrocytes were treated with hydrogen peroxide to induce erythrocyte damage. The extract (at various concentrations) was subsequently incubated with the erythrocytes and later analysed for haemolysis and lipid peroxidation as indices for erythrocyte damage. Results Preliminary investigation of the extract showed that the leaf possessed significant antioxidant and free radical scavenging abilities using in vitro models in a concentration dependent manner (P<0.05). The extract also reduced hydrogen peroxide induced erythrocyte haemolysis and lipid peroxidation significantly when compared with ascorbic acid (P<0.05). The IC50 values were 7.33 mg/mL and 1.58 mg/mL for inhibition of haemolysis and lipid peroxidation, respectively. In all cases, ascorbic acid (the reference antioxidant) possessed higher activity than the extract. Conclusions The findings show that C. papaya leaves possess significant bioactive potential which is attributed to the phytochemicals which act in synergy. Thus, the leaves can be exploited for pharmaceutical and nutritional purposes. PMID:23569948

Reduction of hydrogen peroxide-induced erythrocyte damage by Carica papaya leaf extract.

PubMed

Okoko, Tebekeme; Ere, Diepreye

2012-06-01

To investigate the in vitro antioxidant potential of Carica papaya (C. papaya) leaf extract and its effect on hydrogen peroxide-induced erythrocyte damage assessed by haemolysis and lipid peroxidation. Hydroxyl radical scavenging activities, hydrogen ion scavenging activity, metal chelating activity, and the ferrous ion reducing ability were assessed as antioxidant indices. In the other experiment, human erythrocytes were treated with hydrogen peroxide to induce erythrocyte damage. The extract (at various concentrations) was subsequently incubated with the erythrocytes and later analysed for haemolysis and lipid peroxidation as indices for erythrocyte damage. Preliminary investigation of the extract showed that the leaf possessed significant antioxidant and free radical scavenging abilities using in vitro models in a concentration dependent manner (P<0.05). The extract also reduced hydrogen peroxide induced erythrocyte haemolysis and lipid peroxidation significantly when compared with ascorbic acid (P<0.05). The IC50 values were 7.33 mg/mL and 1.58 mg/mL for inhibition of haemolysis and lipid peroxidation, respectively. In all cases, ascorbic acid (the reference antioxidant) possessed higher activity than the extract. The findings show that C. papaya leaves possess significant bioactive potential which is attributed to the phytochemicals which act in synergy. Thus, the leaves can be exploited for pharmaceutical and nutritional purposes.

[Antioxidative activities of two metabolites of cultured marine fungus, Halorosellinia oceanicum 323 in vitro].

PubMed

Luo, Jinghui; Yang, Yingbao; Lin, Yongcheng; Chen, Zhiliang; Jiang, Guangce

2004-03-01

To investigate the antioxidative effects of 323-A and 323-B, two isomers extracted from the metabolites of cultured marine fungus, Halorosellinia oceanicum 323 in vitro. NADH-PMS-NBT system was used to produce superoxide free radical (O2*-), EDTANa2-Fe(II)-H2O2 system to generate hydroxyl free radical (*OH), H2O2 to stimulate oxidative hemolysis of erythrocytes of rats, Cys-Fe2+ to induce malondialdehyde (MDA) production in homogenates, and ferrous-ascorbic acid system to increase the turbidity of mitochondria suspension in the liver of rats. And the antioxidative activities of 323-A and 323-B were studied. 323-A and 323-B not only scavenge O2*- and *OH produced by the experimental systems directly, but also inhibit H2O2 stimulated oxidative hemolysis of erythrocytes of rats, depress MDA production in homogenates induced by Cys-Fe2+ system, and reduce the turbidity of mitochondria suspension in the liver of rats increased by ferrous-ascorbic acid system in vitro. 323-A and 323-B showed comprehensive cleaning actions on free radicals and protective effects on the functions of tissues and cells against oxidative lesion. The results suggested that the marine microorganic metabolites might be a novel and profound source of antioxidative reagents.

Antioxidant activities of different solvent extracts of Piper retrofractum Vahl. using DPPH assay

NASA Astrophysics Data System (ADS)

Jadid, Nurul; Hidayati, Dewi; Hartanti, Sylviana Rosyda; Arraniry, Byan Arasyi; Rachman, Rizka Yuanita; Wikanta, Wiwi

2017-06-01

Piper retrofractum Vahl., which belongs to the family Piperaceae, is geographically dispersed in tropical region including Indonesia. They are well-known spice possessing high medicinal properties. This study aimed to determine the antioxidant activity of P. retrofractum fruit, extracted with different solvents (methanol, ethyl acetate, n-hexane) using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. This research was carried out using different concentrations of methanol, ethyl acetate, and n-hexane extracts, (0, 5, 15, 30, 45, 60 ppm). Ascorbic acid was also used as positive antioxidant control. The percentage of inhibition and IC50 were measured. The results showed that the DPPH free radicals were scavenged by all plant extracts in a concentration dependent manner. Moreover, the IC50 values for DPPH radicals with methanol, ethyl acetate and n-hexane extract of the P. retrofractum Vahl. were found to be 101.74; 66.12 and 57.66 ppm, respectively. Interestingly, the IC50 value of n-hexane extract (57.66 ppm) was lower than ascorbic acid (66.12 ppm), indicating that n-hexane extract was a more potent scavenger of free radicals than methanol and ethyl acetate extracts. Taken together, our results suggested that n-hexane extract of P. Retrofractum Vahl. might contain potential antioxidant compounds.

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

PubMed

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

2016-10-01

Lead exposure has negative effects on developing nervous system and induces apoptosis in newly generated neurons. Natural antioxidants (i.e. Ascorbic acid and Garlic) might protect against lead-induced neuronal cell damage. The aim of the present study was to investigate the protective effects of Ascorbic acid and Garlic administration during pregnancy and lactation on lead-induced apoptosis in rat developing hippocampus. Timed pregnant Wistar rats were administrated with Lead (1500 ppm) via drinking water (Pb group) or lead plus Ascorbic acid (Pb + AA Group, 500 mg/kg, IP), or lead plus Garlic Extract (Pb + G Group, 1 ml garlic juice/100 g BW, via Gavage) from early gestation (GD 0) until postnatal day 50 (PN 50). At the end of experiments, the pups' brains were carefully dissected. To identify neuronal death, the brain sections were stained with TUNEL assay. Mean of blood and brain lead levels increased significantly in Pb group comparing to other studied groups (P < 0.01). There was significant reduction in blood and brain lead level in Pb + AA and Pb + G groups when compared to those of Pb group (P < 0.01). The mean number of TUNEL positive cells in the CA1, CA3, and DG was significantly lower in the groups treated by either Ascorbic acid or Garlic (P < 0.05). Administration of Ascorbic acid and Garlic during pregnancy and lactation protect against lead-induced neuronal cell apoptosis in the hippocampus of rat pups partially via the reduction of Pb concentration in the blood and in the brain.

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

NASA Astrophysics Data System (ADS)

Pielesz, Anna; Biniaś, Dorota; Bobiński, Rafał; Sarna, Ewa; Paluch, Jadwiga; Waksmańska, Wioletta

2017-10-01

Wound treatment and healing is complex and is comprised of an elaborate set of processes including cellular, spectroscopic and biochemical ones as well as the ;reaction; of local tissue to thermal injury. Vitamin C as L-ascorbic acid (LA) prevents injurious effects of oxidants because it reduces reactive oxygen species to stable molecules, it becomes oxidized to the short-lived ascorbyl radical. As a result, antioxidant treatment may contribute to minimizing injury in burn patients. The aim of this study is to assess changes in molecular structure of collagen extracted from human epidermis burn wound scab during incubation of the epidermis in L-ascorbic acid solution. The study will be performed using FTIR and FT Raman spectroscopies. During this research it was observed that the intensity of Raman peaks increased where healing was being modified by LA. The intensity of the amide III band at 1247 cm- 1 relative to the intensity at 1326 cm- 1 was used to test tissue repair degree at the incision site. FTIR spectra were recorded from frozen specimens of serum modified by LA; an analysis of shifts in the amide I band position was conducted. The appearance of a new band for frozen samples modified by LA was observed around 1149-1220 cm- 1. The above conclusions confirmed the creation of hydrogen bonds between Nsbnd H stretch and Cdbnd O. Samples being incubated in solutions of L-ascorbic acid demonstrated the absence of electrophoretic bands of albumin. Alterations in the surface of the skin incubated in L-ascorbic acid were investigated with the use of Scanning Electron Microscopy (SEM). A decrease in external symptoms of burn injury was noted in the damaged epidermis incubated in L-ascorbic acid.

Physicochemical and antioxidant properties of Algerian honey.

PubMed

Khalil, Ibrahim; Moniruzzaman, Mohammed; Boukraâ, Laïd; Benhanifia, Mokhtar; Islam, Asiful; Islam, Nazmul; Sulaiman, Siti Amrah; Gan, Siew Hua

2012-09-20

The aim of the present study was to characterize the physical, biochemical and antioxidant properties of Algerian honey samples (n = 4). Physical parameters, such as pH, moisture content, electrical conductivity (EC), total dissolved solids (TDS), color intensity, total sugar and sucrose content were measured. Several biochemical and antioxidant tests were performed to determine the antioxidant properties of the honey samples. The mean pH was 3.84 ± 0.01, and moisture the content was 13.21 ± 0.16%. The mean EC was 0.636 ± 0.001, and the mean TDS was 316.92 ± 0.92. The mean color was 120.58 ± 0.64 mm Pfund, and the mean 5-hydroxymethylfurfural (HMF) content was 21.49 mg/kg. The mean total sugar and reducing sugar contents were 67.03 ± 0.68 g/mL and 64.72 ± 0.52 g/g, respectively. The mean sucrose content was 2.29 ± 0.65%. High mean values of phenolic (459.83 ± 1.92 mg gallic acid/kg), flavonoid (54.23 ± 0.62 mg catechin/kg), ascorbic acid (159.70 ± 0.78 mg/kg), AEAC (278.15 ± 4.34 mg/kg), protein (3381.83 ± 6.19 mg/kg) and proline (2131.47 ± 0.90) contents, as well as DPPH (39.57% ± 4.18) and FRAP activities [337.77 ± 1.01 µM Fe (II)/100 g], were also detected, indicating that Algerian honey has a high antioxidant potential. Strong positive correlations were found between flavonoid, proline and ascorbic acid contents and color intensity with DPPH and FRAP values. Thus, the present study revealed that Algerian honey is a good source of antioxidants.

Healthful and nutritional components in select Florida tropical fruits

USDA-ARS?s Scientific Manuscript database

Fourteen tropical fruits from south Florida (red guava, white guava, carambola, red pitaya (red dragon), white pitaya (white dragon), mamey, sapodilla, lychee, longan, green mango, ripe mango, green papaya and ripe papaya) were evaluated for phenolic compounds, antioxidant activity, ascorbic acid (v...

Effect of ascorbic acid and alpha tocopherol supplementation on acute restraint stress induced changes in testosterone, corticosterone and nor epinephrine levels in male Sprague Dawley rats.

PubMed

Lodhi, Ghulam Mustafa; Latif, Rabia; Hussain, Muhammad Mazhar; Naveed, Abdul Khaliq; Aslam, Muhammad

2014-01-01

Stress of various origins suppresses male reproductive functions through releasing stress hormones. Antioxidant like ascorbic acid (AA) and alpha tocopherol (AT) have been thought to protect the body against stress induced damage. Whether, these antioxidants confer protection against the stress induced increased levels of corticosterone and nor-epinephrine, and decreased testosterone secretion have been investigated in this study. This quasi experimental study was carried out at the Department of Physiology, Army Medical College Rawalpindi in collaboration with National Institute of Health, Islamabad during March to September 2009. Eighty male Sprague Dawley rats were divided into five groups with sixteen rats in each group. Group-I served as the control without stress while group-II was exposed to restraint stress for 6 hours, group-III was administered AA, group-IVAT and group-V was supplemented with both the antioxidants along with standard diet for one month. All antioxidant supplemented groups were exposed to restraint stress for 6 hours. Immediately after the stress episode, blood sample was obtained for the assay of serum testosterone, serum corticosterone by EIA and plasma nor-epinephrine levels by ELISA. Data were analyzed on SPSS-13 and p-value less than 0.05 was considered significant. Acute restraint stress resulted in a statistically significant rise in corticosterone and nor-epinephrine levels and fall in serum testosterone levels. AA supplementation for one month revealed insignificant changes in stress induced hormonal parameters. AT alone and in combination with ascorbic acid prevented the fall in testosterone level as well as rise in corticosterone, however nor-epinephrine levels remained unchanged. Supplementation with AT alone or in combination with AA prevent reduction in testosterone and rise in corticosterone levels while keeping the nor-epinephrine levels unchanged after acute restraint stress in Sprague Dawley rats.

Polyphenol composition and antioxidant activity of Kei-apple (Dovyalis caffra) juice.

PubMed

Loots, Du Toit; van der Westhuizen, Francois H; Jerling, Johann

2006-02-22

The polyphenolic and ascorbate (ASC) components as well as the antioxidant capacity of Kei-apple (Dovyalis caffra) juice were analyzed and compared to three other fruit juices. The Kei-apple juice had significantly the highest total polyphenolic concentrations (1013 mg gallic acid equivalent/L), and solid phase (C(18)) fractionation identified the majority of these polyphenols to be phenolic acids. The Kei-apple juice also had significantly the highest ASC concentrations (658 mg/L), which showed exceptional heat stability with very little conversion to dehydroascorbate (DHA). Antioxidant capacities of both the unfractionated fruit juices and their solid phase-extracted fractions, as determined by oxygen radical absorbance capacity and ferric reducing antioxidant power analyses, correlated well to the polyphenol concentrations. Gas chromatography-mass spectrometry analyses showed caffeic acid as the most abundant polyphenol present (128.7 mg/L) in the Kei-apple juice; it contributed to 63% of the total antioxidant capacity (of all of the individual compounds identified). Other notable polyphenols identified in higher concentrations included p-coumaric acid, p-hydroxyphenylacetic acid, and protocatechuic acid. Our results therefore support the putative high antioxidant value linked to this fruit and better define this potential in terms of the major antioxidants that exist in the Kei-apple.

Chemical, Bioactive, and Antioxidant Potential of Twenty Wild Culinary Mushroom Species.

PubMed

Sharma, S K; Gautam, N

2015-01-01

The chemical, bioactive, and antioxidant potential of twenty wild culinary mushroom species being consumed by the people of northern Himalayan regions has been evaluated for the first time in the present study. Nutrients analyzed include protein, crude fat, fibres, carbohydrates, and monosaccharides. Besides, preliminary study on the detection of toxic compounds was done on these species. Bioactive compounds evaluated are fatty acids, amino acids, tocopherol content, carotenoids (β-carotene, lycopene), flavonoids, ascorbic acid, and anthocyanidins. Fruitbodies extract of all the species was tested for different types of antioxidant assays. Although differences were observed in the net values of individual species all the species were found to be rich in protein, and carbohydrates and low in fat. Glucose was found to be the major monosaccharide. Predominance of UFA (65-70%) over SFA (30-35%) was observed in all the species with considerable amounts of other bioactive compounds. All the species showed higher effectiveness for antioxidant capacities.

Effect of buffer and antioxidant on stability of a mercaptopurine suspension.

PubMed

Aliabadi, Hamidreza Montazeri; Romanick, Marcel; Desai, Sunil; Lavasanifar, Afsaneh

2008-03-01

The stability of standard and modified mercaptopurine suspensions when stored at room temperature and under refrigerated conditions to test the feasibility of increasing shelf life was studied. A 50-mg/mL mercaptopurine suspension was compounded by adding simple syrup, cherry syrup, and sterile water for irrigation to triturated mercaptopurine tablets for the initial reference formulation. Three additional formulations were prepared by adding an antioxidant (ascorbic acid 10 mg), a buffer (sodium phosphate monobasic monohydrate 500 mg), and a combination of antioxidant and buffer to the reference formulation. Each compounded batch was divided into two parts and stored in amber bottles at room temperature (19-23 degrees C) or under refrigerated conditions (4-8 degrees C). Analysis through high-performance liquid chromatography determined mercaptopurine levels after three and seven days and weekly thereafter for at least two weeks after shelf life was reached under specified storage conditions. Solutions with at least 93% of the original mercaptopurine concentration and with no observable sign of aggregation or cake formation were considered stable. The reference suspension of mercaptopurine showed an acceptable physical and chemical stability of up to 5 weeks when stored at room temperature. The addition of ascorbic acid extended the shelf life of the compounded suspension to 11 weeks. However, the addition of sodium phosphate monobasic did not improve the stability of mercaptopurine in the suspension. The results showed a higher stability for all formulations after storage at room temperature compared with those stored in a refrigerator. A standard oral suspension of mercaptopurine contained an acceptable drug concentration for up to 5 weeks when stored at room temperature. The addition of ascorbic acid at a concentration of 0.1% w/v to the standard formulation increased the suspension's shelf life at room temperature to 11 weeks.

Circadian time structure of circulating plasma lipid peroxides, antioxidant enzymes and other small molecules in peptic ulcers.

PubMed

Singh, Ranjana; Singh, Rajesh Kumar; Masood, Tariq; Tripathi, Anil Kumar; Mahdi, Abbas Ali; Singh, Raj Kumar; Schwartzkopff, Othild; Cornelissen, Germaine

2015-12-07

The circadian rhythm, as part of a broad time structure (chronome) of lipid peroxides and antioxidant defense mechanisms may relate to prevention, efficacy and management of preventive and curative chronotherapy. Fifty newly diagnosed patients with peptic ulcers, 30-45 years of age, and 60 age-matched clinically healthy volunteers were synchronized for one week with diurnal activity from about 06:00 to about 22:00 and nocturnal rest. Breakfast was served around 08:30, lunch around 13:30 and dinner around 20:30. Drugs known to affect the free-radical systems were not taken. Blood samples were collected at 6-hour intervals for 24h under standardized, presumably 24-hour synchronized conditions. Plasma lipid peroxides, in the form of malondialdehyde (MDA), blood superoxide dismutase (SOD), glutathione peroxide (GPx), glutathione reductase (GR), catalase (CAT) activities, and serum total protein, albumin, ascorbic acid, total serum cholesterol, and HDL-cholesterol concentrations were determined. By population-mean cosinor analysis, a marked circadian variation was demonstrated for all variables in healthy subjects and in ulcer patients (p<0.001). As compared to controls, patients had a lower MESOR of MDA, SOD, GPx, GR, ascorbic acid, and HDL-C. They also had smaller circadian amplitude of SOD, CAT, GPx, GR, ascorbic acid, T-C, and HDL-C, but larger circadian amplitude of MDA and albumin. As compared to healthy subjects, the circadian acrophase of ulcer patients occurred later for MDA and GR and earlier for GPx. Mapping circadian rhythms, important chronome components that include trends with age and extra-circadian components characterizing antioxidants and pro-oxidants, is needed for exploring their putative role as markers in the treatment and management of peptic ulcers. Copyright © 2015. Published by Elsevier B.V.

A Review on the Effect of Drying on Antioxidant Potential of Fruits and Vegetables.

PubMed

Kamiloglu, Senem; Toydemir, Gamze; Boyacioglu, Dilek; Beekwilder, Jules; Hall, Robert D; Capanoglu, Esra

2016-07-29

The role of antioxidants in human nutrition has gained increased interest, especially due to their associated health beneficial effects for a number of chronic diseases, including cardiovascular diseases and certain types of cancer. Fruits and vegetables are perishable and difficult to preserve as fresh products. Dried fruits and vegetables can be easily stored, transported at relatively low cost, have reduced packing costs, and their low water content delays microbial spoilage. Air-, freeze-, microwave- and sun-drying are among the most thoroughly studied drying methods. This review provides an overview of recent findings on the effects of different drying techniques on major antioxidants of fruits and vegetables. In particular, changes in ascorbic acid, carotenoids, flavonoids, phenolic acids, total phenolics, and antioxidant activity are discussed in detail.

Potentiating effects of honey on antioxidant properties of lemon-flavoured black tea.

PubMed

Pereira, Carla; Barros, Lillian; Vilas-Boas, Miguel; Ferreira, Isabel C F R

2013-03-01

Health benefits including antioxidant potential of black tea (Camellia sinensis), lemon (Citrus limon) and honey bees (Apis mellifera) have been extensively reported. Nevertheless, nothing is reported about the effects of their concomitant use. Herein, those effects were evaluated in infusions of lemon-flavoured black tea with three different kinds of honey (light amber, amber and dark amber) from Lavandula stoechas, Erica sp. pl. and other indigenous floral species from north-east Portugal, a region with high amounts of this food product. Data obtained showed that the use of honey (dark amber>amber>light amber) potentiates the antioxidant activity of lemon-flavoured black tea, increasing the reducing power and lipid peroxidation inhibition properties, as also the antioxidant contents such as phenolics, flavonoids and organic acids including ascorbic acid.

Stability of bioactive compounds in butiá (Butia odorata) fruit pulp and nectar.

PubMed

Hoffmann, Jessica Fernanda; Zandoná, Giovana Paula; Dos Santos, Priscila Silveira; Dallmann, Camila Müller; Madruga, Francine Bonemann; Rombaldi, Cesar Valmor; Chaves, Fábio Clasen

2017-12-15

Butia odorata is a palm tree native to southern Brazil whose fruit (known as butiá) and leaves are used to make many food products and crafts. Butiá contain several biologically active compounds with potential health benefits. However, processing conditions can alter quality attributes including bioactive compound content. This study evaluated the stability of bioactive compounds in butiá pulp upon pasteurization, during 12months of frozen storage, and in butiá nectar after a 3-month storage period. Pulp pasteurization resulted in a reduction in phenolic, flavonoid, carotenoid, and ascorbic acid contents. After a 12-month frozen storage period, flavonoid, phenolic, and ascorbic acid contents decreased while carotenoid content remained unaltered. Carotenoid, ascorbic acid, and phenolic contents were unaffected by the 3-month storage of butiá nectar; however, flavonoid content and antioxidant potential were reduced. Despite bioactive compound degradation upon heat treatment and storage, butiá nectar remained rich in phenolics, especially (-)-epicatechin, rutin, and (+)-catechin. Copyright © 2017 Elsevier Ltd. All rights reserved.

In vitro stabilization of a low-tin bone-imaging agent (99mTc-Sn-HEDP) by ascorbic acid.

PubMed

Tofe, A J; Francis, M D

1976-09-01

The presence of oxidants in the 99mTc-pertechnetate and of oxygen in diagnostic kits containing low concentrations of Sn(II) has a detrimental effect upon in vitro and in vivo stability. Maintaining a nitrogen atmosphere or increasing the Sn(II) concentration inhibits the formation of 99mTcO4-. However, the latter remedy is likely to cause uptake in the reticuloendothelial system and has been associated with false positive or negative brain scans. We used ascorbic acid (an antioxidant) to ensure the in vitro stability with the low-Sn(II) bone agent disodium etidronate. In vitro stability studies by instant thin-layer chromatography, using high-acitivity generators and "instant pertechnetate," yielded less than 2% free pertechnetate at 24 hr after preparation. Distribution studies in guinea pigs show neither altered distribution of the bone agent nor abnormal distribution of ascorbic acid, suggesting its sole function as a noncomplexing stabilizer.

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

PubMed Central

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

2016-01-01

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

Prospecting Russula senecis: a delicacy among the tribes of West Bengal

PubMed Central

Khatua, Somanjana; Dutta, Arun Kumar

2015-01-01

Russula senecis, a worldwide distributed mushroom, is exclusively popular among the tribal communities of West Bengal for food purposes. The present study focuses on its reliable taxonomic identification through macro- and micro-morphological features, DNA barcoding, confirmation of its systematic placement by phylogenetic analyses, myco-chemicals and functional activities. For the first time, the complete Internal Transcribed Spacer region of R. senecis has been sequenced and its taxonomic position within subsection Foetentinae under series Ingratae of the subgen. Ingratula is confirmed through phylogenetic analysis. For exploration of its medicinal properties, dried basidiocarps were subjected for preparation of a heat stable phenol rich extract (RusePre) using water and ethanol as solvent system. The antioxidant activity was evaluated through hydroxyl radical scavenging (EC50 5 µg/ml), chelating ability of ferrous ion (EC50 0.158 mg/ml), DPPH radical scavenging (EC50 1.34 mg/ml), reducing power (EC50 2.495 mg/ml) and total antioxidant activity methods (13.44 µg ascorbic acid equivalent/mg of extract). RusePre exhibited antimicrobial potentiality against Listeria monocytogenes, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus. Furthermore, different parameters were tested to investigate its chemical composition, which revealed the presence of appreciable quantity of phenolic compounds, along with carotenoids and ascorbic acid. HPLC-UV fingerprint indicated the probable existence of at least 13 phenolics, of which 10 were identified (pyrogallol > kaempferol > quercetin > chlorogenic acid > ferulic acid, cinnamic acid > vanillic acid > salicylic acid > p-coumaric acid > gallic acid). Result from the present work suggests that the fraction, RusePre, may open novel prospect as a functional ingredient in antioxidant supplements and in drugs to treat infectious disease. PMID:25780764

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

PubMed

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

2010-08-01

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

Enhancing growth performance and systemic acquired resistance of medicinal plant Sesbania sesban (L.) Merr using arbuscular mycorrhizal fungi under salt stress

PubMed Central

Abd_Allah, Elsayed Fathi; Hashem, Abeer; Alqarawi, Abdulaziz Abdullah; Bahkali, Ali Hassan; Alwhibi, Mona S.

2015-01-01

Pot experiments were conducted to evaluate the damaging effects of salinity on Sesbania sesban plants in the presence and absence of arbuscular mycorrhizal fungi (AMF). The selected morphological, physiological and biochemical parameters of S. sesban were measured. Salinity reduced growth and chlorophyll content drastically while as AMF inoculated plants improved growth. A decrease in the number of nodules, nodule weight and nitrogenase activity was also evident due to salinity stress causing reduction in nitrogen fixation and assimilation potential. AMF inoculation increased these parameters and also ameliorated the salinity stress to some extent. Antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) as well as non enzymatic antioxidants (ascorbic acid and glutathione) also exhibited great variation with salinity treatment. Salinity caused great alterations in the endogenous levels of growth hormones with abscisic acid showing increment. AMF inoculated plants maintained higher levels of growth hormones and also allayed the negative impact of salinity. PMID:25972748

Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Agaricomycetes), Inhibits Candida Biofilms: A Metabolomic Approach.

PubMed

Bhardwaj, Anuja; Gupta, Payal; Kumar, Navin; Mishra, Jigni; Kumar, Ajai; Rakhee, Rajput; Misra, Kshipra

2017-01-01

This article presents a comparative gas chromatography (GC)-mass spectrometry (MS)-based metabolomic analysis of mycelia and fruiting bodies of the medicinal mushroom Ganoderma lucidum. Three aqueous extracts-mycelia, fruiting bodies, and a mixture of them-and their sequential fractions (methanolic and ethyl acetate), prepared using an accelerated solvent extractor, were characterized by GC-MS to determine volatile organic compounds and by high-performance thin-layer chromatography to quantify ascorbic acid, a potent antioxidant. In addition, these extracts and fractions were assessed against Candida albicans and C. glabrata biofilms via the XTT reduction assay, and their antioxidant potential was evaluated. Application of chemometrics (hierarchical cluster analysis and principal component analysis) to GC data revealed variability in volatile organic compound profiles among G. lucidum extracts and fractions. The mycelial aqueous extract demonstrated higher anti-Candida activity and ascorbic acid content among all the extracts and fractions. Thus, this study illustrates the preventive effect of G. lucidum against C. albicans and C. glabrata biofilms along with its nutritional value.

Effect of harvest date on the nutritional quality and antioxidant capacity in 'Hass' avocado during storage.

PubMed

Wang, Meng; Zheng, Yusheng; Khuong, Toan; Lovatt, Carol J

2012-11-15

The effect of harvest date on nutritional compounds and antioxidant activity (AOC) in avocado (Persea americana Mill. cv Hass) fruit during storage was determined. The fruits were harvested at seven different dates and ripened at 25 °C following 21 or 35 days of cold storage. The results indicated that the phenolic and glutathione contents were increased and the ascorbic acid content was not significantly different in early harvested fruit (January to March), and the phenolic, ascorbic acid and glutathione contents were increased slightly and then decreased on late harvested fruit (April to June). Similar trends were observed in the changes of AOC. Furthermore, AOC in early harvested fruit after storage for 35 days was much higher than that in late harvested fruit after storage for 21 days. Therefore, avocado can be harvested earlier for economic benefits according to the market and can keep high nutritional value for human health benefits. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of baking and boiling on the nutritional and antioxidant properties of sweet potato [Ipomoea batatas (L.) Lam.] cultivars.

PubMed

Dincer, Cuneyt; Karaoglan, Mert; Erden, Fidan; Tetik, Nedim; Topuz, Ayhan; Ozdemir, Feramuz

2011-11-01

The effects of baking and boiling on the nutritional and antioxidant properties of three sweet potato cultivars (Beniazuma, Koganesengan, Kotobuki) cultivated in Turkey were investigated. The samples were analyzed for proximate composition, total phenolic content, ascorbic acid, β-carotene, antiradical activity, and free sugars. The dry matter, protein, and starch contents of the sweet potatoes were significantly changed by the treatments while the ash and crude fiber contents did not differ as significantly. The β-carotene contents of baked and boiled sweet potatoes were lower than those of fresh sweet potatoes; however, the total phenolic and ascorbic acid contents of the baked and boiled sweet potatoes were higher than those of the fresh samples. Generally, the antiradical activity of the sweet potatoes increased with the treatments. Sucrose, glucose, and fructose were quantified as free sugars in all fresh sweet potatoes; however, maltose was determined in the treated samples. In terms of the analyzed parameters, there were no explicit differences among the sweet potato cultivars.

Implication of processing and differential blending on quality characteristics in nutritionally enriched ketchup (Nutri-Ketchup) from acerola and tomato.

PubMed

Prakash, Anand; Prabhudev, S H; Vijayalakshmi, M R; Prakash, Maya; Baskaran, Revathy

2016-08-01

The present study was focused on the development of nutritionally enriched ketchup (Nutri-ketchup) from acerola and tomato and evaluation of the effect of blending and processing on physicochemical characteristics, phytonutrients retention, antioxidant activity and sensorial quality. Acerola and tomato pulps blended in various ratios viz. 100:0, 75:25, 50:50, 25:75 and 0:100 were used for the preparation of five formulations of ketchup and compared with commercially available tomato ketchup. The retention of phytonutrients varied among formulations viz. ascorbic acid- ~18-29 %, anthocyanins- ~17-25 %, phenolics- ~11-70 %, flavonoids- ~24-42 %, lycopene- ~24-33 % and carotenoids- ~23-34 %. Antioxidant capacity of 80 % methanol extract and ascorbic acid fraction of the formulations evaluated using DPPH and ABTS assays showed higher activity than the commercial sample. Ketchup prepared from acerola and tomato blend of 75:25 showed the best overall quality, while all the other formulations were also sensorily acceptable.

Oxidative Stress and Nucleic Acid Oxidation in Patients with Chronic Kidney Disease

PubMed Central

Sung, Chih-Chien; Hsu, Yu-Chuan; Lin, Yuh-Feng

2013-01-01

Patients with chronic kidney disease (CKD) have high cardiovascular mortality and morbidity and a high risk for developing malignancy. Excessive oxidative stress is thought to play a major role in elevating these risks by increasing oxidative nucleic acid damage. Oxidative stress results from an imbalance between reactive oxygen/nitrogen species (RONS) production and antioxidant defense mechanisms and can cause vascular and tissue injuries as well as nucleic acid damage in CKD patients. The increased production of RONS, impaired nonenzymatic or enzymatic antioxidant defense mechanisms, and other risk factors including gene polymorphisms, uremic toxins (indoxyl sulfate), deficiency of arylesterase/paraoxonase, hyperhomocysteinemia, dialysis-associated membrane bioincompatibility, and endotoxin in patients with CKD can inhibit normal cell function by damaging cell lipids, arachidonic acid derivatives, carbohydrates, proteins, amino acids, and nucleic acids. Several clinical biomarkers and techniques have been used to detect the antioxidant status and oxidative stress/oxidative nucleic acid damage associated with long-term complications such as inflammation, atherosclerosis, amyloidosis, and malignancy in CKD patients. Antioxidant therapies have been studied to reduce the oxidative stress and nucleic acid oxidation in patients with CKD, including alpha-tocopherol, N-acetylcysteine, ascorbic acid, glutathione, folic acid, bardoxolone methyl, angiotensin-converting enzyme inhibitor, and providing better dialysis strategies. This paper provides an overview of radical production, antioxidant defence, pathogenesis and biomarkers of oxidative stress in patients with CKD, and possible antioxidant therapies. PMID:24058721

Stabilization of anthocyanins in blackberry juice by glutathione fortification.

PubMed

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

2017-10-18

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

Anti-inflammatory and antioxidant activities of ethanolic extract of aerial parts of Vernonia patula (Dryand.) Merr.

PubMed Central

Hira, Arpona; Dey, Shubhra Kanti; Howlader, Md. Sariful Islam; Ahmed, Arif; Hossain, Hemayet; Jahan, Ismet Ara

2013-01-01

Objective To investigate the inflammatory and antioxidant activities of ethanolic extract of aerial part of Vernonia patula (Dryand.) Merr (EAV). Methods The anti-inflammatory activity of EAV was studied using carrageenan and histamine-induced rat paw edema test at different doses (100, 200 and 400 mg/kg body weight). DPPH free radical scavenging, nitric oxide scavenging, reducing power and Fe2+ ion chelating ability were used for determining antioxidant activities. Results The EAV, at the dose of 400 mg/kg, showed a significant anti-inflammatory activity (P<0.01) both in the carrageenan and histamine-induced oedema test models in rats, showing 62.86% and 64.42% reduction in the paw volume comparable to that produced by the standard drug indomethacin (67.26% and 66.01%) at 5 h respectively. In DPPH free radical scavenging test, IC50 value for EAV was found fairly significant 36.59 µg/mL when compared to the IC50 value of the reference standards ascorbic acid 8.97 µg/mL. The IC50 values of the extract and ascorbic acid were 47.72 and 12.39 µg/mL, respectively in nitric oxide scavenging assay. The IC50 value of the EAV (33.59 µg/mL) as percentage of Fe2+ ion chelating ability was also found significant compared to that of EDTA (9.16 µg/mL). The maximum absorbance for reducing power assay was found to be 1.928 at 100 µg/mL when compared to 2.449 for standard ascorbic acid. The total phenolic content was 198.81 mg/g of gallic acid equivalent. Acute toxicity test showed that the plant might be safe for pharmacological uses up to a dose level of 3 200 mg/kg of body weight in rats. Conclusions Therefore, the obtained results suggest the acute anti-inflammatory and antioxidant activities of the EAV and thus provide the scientific basis for the traditional uses of this plant part as a remedy for inflammations. PMID:24075345

Seasonal- and temperature-dependent variation in CNS ascorbate and glutathione levels in anoxia-tolerant turtles.

PubMed

Pérez-Pinzón, M A; Rice, M E

1995-12-24

We determined the ascorbic acid (ascorbate) and glutathione (GSH) contents of eight regions of the CNS from anoxia-tolerant turtles collected in summer and in winter. Ascorbate was of special interest because it is found in exceptionally high levels in the turtle CNS. The temperature-dependence of CNS ascorbate content was established by comparing levels in animals collected from two geographic zones with different average winter temperatures and in animals re-acclimated to different temperatures in the laboratory. The analytical method was liquid chromatography with electrochemical detection. Turtle ascorbate levels were 30-40% lower in animals acclimatized to winter (2 degrees C) than to summer (23 degrees C) in all regions of the CNS. Similarly, GSH levels were 20-30% lower in winter than in summer. Winter ascorbate levels were higher in turtles from Louisiana (19 degrees C) than in turtles acclimatized to winter in Wisconsin (2 degrees C). Summer and winter levels of ascorbate could be reversed by re-acclimating animals to cold (1 degree C) or warm (23 degrees C) temperatures for at least one week. CNS water content did not differ between cold- and warm-acclimated turtles. Taken together, the data indicated that ascorbate and GSH undergo significant seasonal variation and that the catalyst for change is environmental temperature. Steady-state ascorbate content showed a linear dependence on temperature, with a slope of 1.5% per degree C that was independent of CNS region. Lower levels of cerebral antioxidants in turtles exposed to colder temperatures were consistent with the decreased rate of cerebral metabolism that accompanies winter hibernation. Cerebral ascorbate and GSH levels in the turtle remained similar to or higher than those in mammals, even during winter, however. These findings support the notion that unique mechanisms of antioxidant regulation in the turtle contribute to their tolerance of the hypoxia-reoxygenation that characterizes diving behavior.

Modified atmosphere packaging for fresh-cut 'Kent' mango

USDA-ARS?s Scientific Manuscript database

A modified atmosphere package (MAP) was designed to optimize the quality and shelf-life of fresh-cut ‘Kent’ mango during exposure to common retail display conditions. Synergism of the MAP system with an antioxidant treatment (calcium ascorbate + citric acid) was also investigated. Mango slices in tr...

Antioxidant Properties and Flavonoid Profile in Leaves of Calabrian Lavandula multifida L., an Autochthon Plant of Mediterranean Southern Regions.

PubMed

Panuccio, Maria Rosaria; Fazio, Angela; Papalia, Teresa; Barreca, Davide

2016-04-01

Lavandula multifida is a rare short-lived plant characteristic of Mediterranean basin able to survive in hot and arid climatic conditions on poorly evolved limestone soils. In this work, we characterize the enzymatic antioxidant system and phenolic composition, as well as the antioxidant properties of L. multifida fresh leaves. Enzymatic patterns show high level of peroxidases, ascorbate peroxidase, and dehydroascorbate reductase activities, when compared with L. angustifolia. The same trend is evident in total carotenoids, ascorbic acid, and reduced glutathione, and in the total antioxidant capacity assay. Moreover, RP-DAD-HPLC analyses of EtOH extract, obtained from fresh leaves, reveal main components, carvacrol, vitexin, and 7- or 8-glucoside derivatives of hypolaetin, scutellarein, luteolin, isoscutellarein, apigenin, and chrysoeriol. The analysis of this autochthon plant depicted a series of strategies adopted by L. multifida to survive in its stressful natural habitat and richness in health-promoting compounds that can be a resource for the preservation of this variety in dangerous of extinction. © 2016 Verlag Helvetica Chimica Acta AG, Zürich.

Changes in photosynthetic performance and antioxidative strategies during maturation of Norway maple (Acer platanoides L.) leaves.

PubMed

Lepeduš, Hrvoje; Gaća, Vlatka; Viljevac, Marija; Kovač, Spomenka; Fulgosi, Hrvoje; Simić, Domagoj; Jurković, Vlatka; Cesar, Vera

2011-04-01

Different structural and functional changes take place during leaf development. Since some of them are highly connected to oxidative metabolism, regulation of reactive oxygen species (ROS) abundance is required. Most of the reactive oxygen species ROS in plant cells are produced in chloroplasts as a result of highly energetic reactions of photosynthesis. The aim of our study was to examine the changes in concentration of oxidative stress parameters (TBARS - thiobarbituric acid-reacting substances and protein carbonyls) as well as antioxidative strategies during development of maple (Acer platanoides L.) leaves in the light of their enhanced photosynthetic performance. We reveal that biogenesis of the photosynthetic apparatus during maple leaf maturation corresponded with oxidative damage of lipids, but not proteins. In addition, antioxidative responses in young leaves differed from that in older leaves. Young leaves had high values of non-photochemical quenching (NPQ) and catalase (CAT, EC 1.11.1.6) activity which declined during the maturation process. Developing leaves were characterized by an increase in TBARS level, the content of non-enzymatic antioxidants as well as ascorbate peroxidase activity (APX, EC 1.11.1.11), while the content of protein carbonyls decreased with leaf maturation. Fully developed leaves had the highest lipid peroxidation level accompanied by a maximum in ascorbic acid content and superoxide dismutase activity (SOD, EC1.15.1.1). These observations imply completely different antioxidative strategies during leaf maturation enabling them to perform their basic function. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

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

PubMed

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

2003-02-12

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

Enhancing antioxidant activity, microbial and sensory quality of mango (Mangifera indica L.) juice by γ-irradiation and its in vitro radioprotective potential.

PubMed

Naresh, Kondapalli; Varakumar, Sadineni; Variyar, Prasad Shekhar; Sharma, Arun; Reddy, Obulam Vijaya Sarathi

2015-07-01

Gamma irradiation is an effective method currently being used for microbial decontamination and insect disinfestations of foods. In the present study, mango (Mangifera indica L.) juice was irradiated at doses of 0, 1.0, 3.0 and 5.0 kGy and microbial load, total polyphenols, flavonoids, ascorbic acid content, antioxidant activities, colour and sensory properties were evaluated immediately after irradiation and also during storage. Microbiological assay of the fresh and stored mango juice showed better quality after γ-irradiation. The total polyphenols and flavonoids were significantly (p < 0.05) increased while the ascorbic acid content decreased with the irradiation doses applied. As a result of γ-irradiation, a significant increment in gallic, syringic and chlorogenic acids and a significant reduction in ferulic and synapic acids were noted when analyzed by HPLC. In vitro antioxidant potentials were measured using DPPH, FRAP and NO scavenging assays; the results showed significant enhancement in the activities after irradiation, that correlated well with the increase in phenolic and flavonoid content. γ-irradiation improved the colour of mango juice without any adverse changes in the sensory qualities. Significant in vitro plasmid DNA protection was observed in the presence of mango juice against radiation induced damage, even at the dose of 5 kGy. This study confirmed the potential of γ-irradiation as a method for microbial decontamination and improving the quality of the mango juice without compromising on the sensory attributes.

Cuminum cyminum extract attenuates scopolamine-induced memory loss and stress-induced urinary biochemical changes in rats: a noninvasive biochemical approach.

PubMed

Koppula, Sushruta; Choi, Dong Kug

2011-07-01

Cuminum cyminum Linn. (Apiaceae), cumin, is a popular spice with a long history of medicinal use to treat various symptoms such as diarrhea, flatulence, gynecological, and respiratory diseases. To date, no scientific investigation was reported regarding memory-enhancing and antistress activity of cumin fruits. The present study deals with the memory-enhancing and antistress activities and further the antioxidant status via lipid peroxidation inhibition. Antistress activity was evaluated by inducing stress via forced swimming and the urinary vanillylmandelic acid (VMA) and ascorbic acid were estimated as biomarkers. Memory-enhancing activity was studied by conditioned avoidance response using Cook's pole climbing apparatus in normal and scopolamine-induced amnestic rats. Thiobarbituric acid reactive substances (TBARS) assay was used to evaluate the lipid peroxidation. Daily administration of cumin at doses of 100, 200, and 300 mg/kg body weight 1 h prior to induction of stress inhibited the stress-induced urinary biochemical changes in a dose-dependent manner without altering the levels in normal control groups. The cognition, as determined by the acquisition, retention, and recovery in rats, was observed to be dose-dependent. The extract also produced significant lipid peroxidation inhibition in comparison with known antioxidant ascorbic acid in both rat liver and brain. This study provides scientific support for the antistress, antioxidant, and memory-enhancing activities of cumin extract and substantiates that its traditional use as a culinary spice in foods is beneficial and scientific in combating stress and related disorders.

Ascorbic acid selectively improves large elastic artery compliance in postmenopausal women.

PubMed

Moreau, Kerrie L; Gavin, Kathleen M; Plum, Angela E; Seals, Douglas R

2005-06-01

The compliance of large elastic arteries in the cardiothoracic region decreases with advancing age/menopause and plays an important role in the increased prevalence of cardiovascular diseases in postmenopausal women. We determined whether oxidative stress contributes to the reduced large elastic artery compliance of postmenopausal women. Carotid artery compliance was measured during acute intravenous infusions of saline (baseline control) and supraphysiological doses of the potent antioxidant ascorbic acid in premenopausal (n=10; 23+/-1; mean+/-SE) and estrogen-deficient postmenopausal (n=21; 55+/-1 years) healthy sedentary women. Carotid artery compliance was 56% lower in postmenopausal compared with premenopausal women during baseline control (P<0.0001). Ascorbic acid infusion increased carotid artery compliance by 26% in postmenopausal women (1.11+/-0.07 to 1.38+/-0.08 mm2/mm Hgx10(-1); P<0.001) but had no effect in premenopausal women (2.50+/-0.25 versus 2.43+/-0.20 mm2/mm Hgx10(-1)). Carotid artery diameter, blood pressure, and heart rate were unaffected by ascorbic acid. In the pooled population, the change in arterial compliance with ascorbic acid correlated with baseline waist-to-hip ratio (r=0.56; P=0.001), plasma norepinephrine (r=0.58; P=0.001), and LDL cholesterol (r=0.54; P=0.001). These results suggest that oxidative stress may be an important mechanism contributing to the reduced large elastic artery compliance of sedentary, estrogen-deficient postmenopausal women. Increased abdominal fat storage, sympathetic nervous system activity, and LDL cholesterol may be mechanistically involved in oxidative stress-associated suppression of arterial compliance in postmenopausal women.

Interaction of gold nanoparticles with free radicals and their role in enhancing the scavenging activity of ascorbic acid.

PubMed

Razzaq, Humaira; Saira, Farhat; Yaqub, Azra; Qureshi, Rumana; Mumtaz, Misbah; Saleemi, Samia

2016-08-01

The present study investigates the interaction of citrate stabilized gold nanoparticles (12±1.5nm) (GNPs) with free radicals; 1,1-diphenyl-2-picrylhydrazyl (DPPH) stable and electrochemically generated superoxide, O2(-). Different experiments were designed to understand the interaction between GNPs and DPPH by employing cyclic voltammetry, UV-vis spectroscopy and computational chemistry using 6-311G basis set. The increase in heterogeneous rate constant, ksh, of DPPH upon addition of GNPs pointed towards possible complex formation, DPPH-GNPs which were further explained by a model assuming surface adsorption of DPPH on GNPs. Further, the model was validated by studying interaction of GNPs with a biologically important free radical, O2(-). Exciting result in terms of disappearance of anodic peak after GNPs addition confirmed that gold nanoparticles interacted with stable as well as unstable free radicals. Also, the stoichiometry of the most stable complex GNP-DPPH was determined from UV-vis spectroscopy by applying Job's method. The GNP-DPPH complex was found to be active with 46.0% reduction of the IC50 value of standard antioxidant, ascorbic acid (AA), indicating its role in enhancing antioxidant activity. Hence, this study presents a simple and potential approach to enhance the efficiency of natural antioxidants without modifying their structure, or involving the complex functionalization of GNPs with antioxidants. Copyright © 2016. Published by Elsevier B.V.

Natural extracts versus sodium ascorbate to extend the shelf life of meat-based ready-to-eat meals.

PubMed

Price, Alejandra; Díaz, Pedro; Bañón, Sancho; Garrido, Maria Dolores

2013-10-01

The effect of grape seed and green tea extracts was compared with effect of sodium ascorbate on bacterial spoilage, lipid stability and sensory quality in cooked pork meatballs during refrigerated storage. Meatballs were stored at 4  in aerobic packaging for 0, 4, 8, 12 and 16 days under retail display conditions. Lipid oxidation was evaluated as thiobarbituric acid reactive substances, volatile compounds and cholesterol oxidation products. Colour stability was assessed through CIELab parameters. Microbiological spoilage was determined through total viable, mould and yeast and coliform counts. The samples containing green tea and grape seed extracts showed lower levels of thiobarbituric acid reacting substances, major volatile compounds and microbiological counts than the samples with sodium ascorbate. Formation of cholesterol oxidation products was also inhibited to a greater extent. Colour of meatballs and pork meatballs was not affected by refrigerated storage; however, the addition of extracts provided brown shades. The addition of antioxidants did not modify the sensory attributes except for the colour. Green tea and grape seed extracts were more effective than sodium ascorbate at preventing lipid oxidation.

Surface treatments and coatings to maintain fresh-cut mango quality in storage

USDA-ARS?s Scientific Manuscript database

Edible coatings may improve quality of fresh cut fruit by preventing moisture loss and decreasing gas exchange in storage. This study evaluated the effect of an antioxidant dip made of calcium ascorbate, citric acid and N-acetyl-L-cysteine, followed or not with carboxymethylcellulose (CMC) or carrag...

Ontogenetic changes in vitamin C in selected rice varieties

USDA-ARS?s Scientific Manuscript database

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

Evaluation of nitrate and nitrite contents in pickled fruit and vegetable products

USDA-ARS?s Scientific Manuscript database

Our objective was to investigate nitrate and nitrite contents of acidified and fermented fruits and vegetables. L-ascorbic acid and total phenols were also examined based on the hypothesis that the presence of these antioxidant compounds may influence N-nitrosation reactions upon human consumption. ...

Ascorbic acid as a free radical scavenger in porcine and bovine aqueous humour.

PubMed

Erb, Carl; Nau-Staudt, Kerstin; Flammer, Josef; Nau, Werner

2004-01-01

To study the antioxidant activity, UV absorption, concentration and stability of ascorbic acid (AA) in porcine and bovine aqueous humour (AH). Porcine and bovine AH was taken within 5 min after death and frozen at -70 degrees C. The characteristic UV absorption band of AA and the concentration of AA in AH was determined by UV spectrophotometry. The antioxidant activity of AA to serve as a free radical scavenger in AH has been determined by using a novel fluorescent probe for antioxidants, the azoalkane 2,3-diazabicyclo[2.2.2]oct-2-ene (DBO). The fluorescence lifetime and intensity of this probe reflect the concentration of dissolved antioxidants. The time-resolved fluorescence of DBO (laser excitation at 351 nm) in AH and in a neutral phosphate-buffered saline (PBS) solution containing only the natural amount of AA as an additive were measured. The characteristic UV absorption band of AA has its maximum at 266 nm in AH. The concentration of AA in porcine and bovine AH was found to be 0.547 +/- 0.044 and 1.09 +/- 0.16 mM, respectively, by spectrophotometry. The fluorescence lifetime of the probe DBO was reduced from 320 +/- 5 ns in pure aerated PBS to 205 +/- 5 ns in porcine AH and 165 +/- 3 ns in bovine AH. A detailed kinetic analysis of the lifetime shortening suggests that AA contributes approximately 75 and 85% to the antioxidant activity of porcine and bovine AH, respectively. Our experiments suggest that AA is the major contributor to the antioxidant activity of porcine and bovine AH. The role of AA to serve as an antioxidant in AH is discussed. In addition, UV spectrophotometry is established as an alternative method to determine the concentration of AA in AH. Copyright 2004 S. Karger AG, Basel

Portable ceria nanoparticle-based assay for rapid detection of food antioxidants (NanoCerac)

PubMed Central

Sharpe, Erica; Frasco, Thalia; Andreescu, Daniel; Andreescu, Silvana

2012-01-01

With increased awareness of nutrition and the advocacy for healthier food choices, there exists a great demand for a simple, easy-to-use test that can reliably measure the antioxidant capacity of dietary products. We report development and characterization of a portable nanoparticle based-assay, similar to a small sensor patch, for rapid and sensitive detection of food antioxidants. The assay is based on the use of immobilized ceria nanoparticles, which change color after interaction with antioxidants by means of redox and surface chemistry reactions. Monitoring corresponding optical changes enables sensitive detection of antioxidants in which the nanoceria provides an optical ‘signature’ of antioxidant power, while the antioxidants act as reducing agents. The sensor has been tested for the detection of common antioxidant compounds including ascorbic acid, gallic acid, vanilic acid, quercetin, caffeic acid, and epigallocatechin gallate and its function has been successfully applied for the assessment of antioxidant activity in real samples (teas and medicinal mushrooms). The colorimetric response was concentration dependent, with detection limits ranging from 20–400 μM depending on the antioxidant involved. Steady-state color intensity was achieved within seconds upon addition of antioxidants. The results are presented in terms of Gallic Acid Equivalents (GAE). The sensor performed favorably when compared with commonly used antioxidant detection methods. This assay is particularly appealing for remote sensing applications, where specialized equipment is not available, and also for high throughput analysis of a large number of samples. Potential applications for antioxidant detection in remote locations are envisioned. PMID:23139929

Effect of ascorbic acid on endothelial dysfunction of epicardial coronary arteries in chronic smokers assessed by cold pressor testing.

PubMed

Schindler, T H; Magosaki, N; Jeserich, M; Olschewski, M; Nitzsche, E; Holubarsch, C; Solzbach, U; Just, H

2000-01-01

In chronic smokers there is evidence for increased formation of oxygen-derived free radicals within the vessel wall impairing endothelial function. It has been suggested that the inactivation of endothelium-derived nitric oxide by oxygen free radicals contributes to endothelial dysfunction. Hence, we tested the hypothesis that in chronic smokers the antioxidant ascorbic acid could improve abnormal endothelial function of epicardial coronary arteries. Thirty-one patients (mean age 57 +/- 9 years) referred for routine diagnostic catheterization for evaluation of chest pain and without angiographically significant coronary artery stenoses were randomly assigned to one of the study groups to assess vasomotor response of epicardial coronary arteries due to cold pressor testing (CPT) before and after intravenous infusion of 3 g of ascorbic acid or 100 ml x 0.9% saline infusion. In 6 controls (mean age 55 +/- 3 years) CPT led to a similar increase in luminal area before and after ascorbic acid administration (26.5 +/- 15.0 vs. 28.4 +/- 17.7%, p = NS). In 15 chronic smokers (mean age 55 +/- 9 years), CPT induced a decrease in the luminal area of -18.5 +/- 6.3%. This flow-dependent vasoconstriction was significantly reversed to 7.7 +/- 6.2% (p < or = 0.03) vasodilation after intravenous ascorbic acid administration. In 10 chronic smokers (mean age 57 +/- 11 years) saline infusion (placebo) did not have a significant effect on CPT-induced vasoconstriction (-12.7 +/- 5.1 vs. -13.1 +/- 5.1%, p = NS). The CPT-induced increase in luminal area in chronic smokers after ascorbic acid infusion was significant compared to controls and placebo (each p < or = 0.05). Our assessment of endothelium-independent responses to nitroglycerin revealed no significant differences between the single study groups (p = NS). In chronic smokers acute intravenous administration of ascorbic acid significantly improves CPT-induced coronary endothelium-dependent dysfunction. According to the current understanding, this effect is due to improved cellular redox imbalance and prevention of nitric oxide inactivation in the endothelium and subendothelial space.

Chemical constituents and their acetyl cholinesterase inhibitory and antioxidant activities from leaves of Acanthopanax henryi: potential complementary source against Alzheimer's disease.

PubMed

Zhang, Xiao Dan; Liu, Xiang Qian; Kim, Yang Hee; Whang, Wan Kyunn

2014-05-01

The aim of this study was to investigate chemical constituents of the leaves of Acanthopanax henryi, and their antioxidant, acetyl cholinesterase inhibitory activities. Caffeoyl quinic acid derivates and flavonoids were obtained from A. henry, through column chromatography technologies, and the content of major constituents was determined by the HPLC-UV method. Anti-oxidant activity of the isolated metabolites was evaluated by free radical scavenging (DPPH, ABTS radicals) and superoxide anion scavenging. The results showed that di-caffeoyl quinic acid derivates had stronger antioxidant activity than positive controls (ascorbic acid, trolox and allopurinol). Acetyl cholinesterase inhibitory activity was estimated on the constituents, among which, quercetin, 4-caffeoyl-quinic acid and 4,5-caffeoyl quinic acid were found to have strong acetyl cholinesterase inhibitory activity with IC50 values ranging from 62.6 to 121.9 μM. The present study showed that some of the tested constituents from the leaves of A. henryi exhibit strong antioxidant and acetyl cholinesterase inhibitory effects. This suggest that the leaves of A. henryi can be used as a new natural complementary source of acetyl cholinesterase inhibitors and anti-oxidant agents, thus being a promising potential complementary source against Alzheimer's disease.

Physical and chemical quality characteristics and antioxidant properties of strawberry cultivars (Fragaria × ananassa Duch.) in Greece: assessment of their sensory impact.

PubMed

Zeliou, Konstantina; Papasotiropoulos, Vassilis; Manoussopoulos, Yiannis; Lamari, Fotini N

2018-02-01

There are many factors determining the strawberry organoleptic profile and they are difficult to define. In this study, the sensory, physical, and chemical quality characteristics, the antioxidant properties as examined using ferric reducing antioxidant power (FRAP) and 1-diphenyl-2-picrylhydrazyl (DPPH) assays, the lactone concentration, and the FaFAD1 expression of ripe strawberries (cv. Camarosa, Florida Fortuna, and Sabrina) from Greece were evaluated and their interrelationships were investigated. 'Camarosa' had the highest antioxidant capacity and polyphenol content, although significant intra-cultivar variations of sugars, solid soluble content/titratable acidity (SSC/TA), red color intensity, sweetness, and hardness were recorded. In 'Sabrina' there was a constant lactone presence and FaFAD1 expression; it also had the lowest ascorbic acid content, the highest pH, SSC/TA index, firmness, and sweetness. 'Fortuna' showed the lowest sweetness and aroma indices, whereas 'Camarosa' had intermediate ones. Overall, firmness was correlated with hardness, while pH and SSC/TA index correlated with juiciness and sweetness. Both γ-decalactone and γ-dodecalactone concentrations were correlated with FaFAD1 expression and pH, but they did not solely determine the aroma sensory perception. In total, FRAP values were positively correlated with ascorbic acid and polyphenol content, and negatively with pH. Significant inter- and intra-cultivar variation was recorded, revealing the impact of the genotype and underlining the effect of microenvironmental and cultivation conditions on quality and sensory perception. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Effect of soy sauce on lipid oxidation of irradiated pork patties

NASA Astrophysics Data System (ADS)

Kim, Hyun-Wook; Hwang, Ko-Eun; Choi, Yun-Sang; Choi, Ji-Hun; Lee, Mi-Ai; Song, Dong-Heon; Kim, Hack-Youn; Lee, Ju-Woon; Kim, Cheon-Jei

2013-09-01

This study was conducted to find out the antioxidant effect of the soy sauce on lipid oxidation of electron beam irradiated pork patties. The pork patties prepared with sodium chloride or soy sauce solution at identical salt concentrations were irradiated at 0 or 5 kGy, and peroxide value, conjugated diene, 2-thiobarbituric acid, and free fatty acid values were evaluated for 10 days (4 °C). The irradiated pork patties treated with soy sauce showed the lowest peroxide value and 2-thiobarbituric acid value at the end of storage compared to those prepared with sodium chloride. The irradiated pork patties formulated with soy sauce and 0.5% ascorbic acid had similar 2-thiobarbituric acid and free fatty acid values compared to those of the non-irradiated pork patties treated with sodium chloride. Our results suggested that the soy sauce can retard the lipid oxidation of irradiated pork patty, and a synergistic effect between soy sauce and ascorbic acid was observed.

Cupric ion reducing antioxidant capacity assay for food antioxidants: vitamins, polyphenolics, and flavonoids in food extracts.

PubMed

Apak, Reşat; Güçlü, Kubilay; Ozyürek, Mustafa; Bektas Oğlu, Burcu; Bener, Mustafa

2008-01-01

Antioxidants are health beneficial compounds through their combat with reactive oxygen and nitrogen species and free radicals that may cause tissue damage leading to various diseases. This work reports the development of a simple and widely applicable antioxidant capacity index for dietary polyphenols, vitamins C and E, and plasma antioxidants utilizing the copper(II)-neocuproine (Cu(II)-Nc) reagent as the chromogenic oxidizing agent. This novel method based on an electron-transfer mechanism was named by our research group as 'cupric reducing antioxidant capacity', abbreviated as the CUPRAC method. The method is comprised of mixing the antioxidant solution with aqueous copper(II) chloride, alcoholic neocuproine, and ammonium acetate aqueous buffer at pH 7, and subsequently measuring the developed absorbance at 450 nm after 30 min. Since the color development is fast for compounds like ascorbic acid, gallic acid, and quercetin but slow for naringin and naringenin, the latter compounds are assayed after incubation at 50 degrees C on a water bath for 20 min. The flavonoid glycosides are hydrolyzed to their corresponding aglycones by refluxing in 1.2 M: HCl-containing 50% MeOH so as to exert maximal reducing power towards Cu(II)-Nc. The CUPRAC antioxidant capacities of synthetic mixtures are equal to the sum of individual capacities of antioxidant constituents, indicating lack of chemical deviations from Beer's law. Tests on antioxidant polyphenols demonstrate that the highest CUPRAC capacities are observed for epicatechin gallate, epigallocatechin gallate, quercetin, fisetin, epigallocatechin, catechin, and caffeic acid in this order, in accord with the number and position of the -OH groups as well the conjugation level of the molecule. The parallelism of the linear calibration curves of pure antioxidants in water and in a given complex matrix (plant extract) demonstrates that there are no chemical interactions of interferent nature among the solution constituents, and that the antioxidant capacities of the tested antioxidants are additive, in conformity to the Beer's law. For individual determination of ascorbic acid in fruit juices with a modified CUPRAC procedure, flavonoids are pre-extracted as their La(III) complexes prior to assay. For apricot extracts, a modified version of the CUPRAC assay based on anion exchange separation at pH 3 is applied, since sulfited-dried sample extracts contain the hydrosulfite anion interfering with the determination. For herbal tea infusions, the standard CUPRAC protocol is applied. The CUPRAC reagent is stable, easily accessible, low-cost, and is sensitive toward thiol-type antioxidants unlike FRAP. The reaction is carried out at nearly physiological pH as opposed to the acidic pH of FRAP or to the alkaline pH of Folin methods, constituting a basic advantage for the realistic assay of biological fluids.

Chemical, Bioactive, and Antioxidant Potential of Twenty Wild Culinary Mushroom Species

PubMed Central

Sharma, S. K.; Gautam, N.

2015-01-01

The chemical, bioactive, and antioxidant potential of twenty wild culinary mushroom species being consumed by the people of northern Himalayan regions has been evaluated for the first time in the present study. Nutrients analyzed include protein, crude fat, fibres, carbohydrates, and monosaccharides. Besides, preliminary study on the detection of toxic compounds was done on these species. Bioactive compounds evaluated are fatty acids, amino acids, tocopherol content, carotenoids (β-carotene, lycopene), flavonoids, ascorbic acid, and anthocyanidins. Fruitbodies extract of all the species was tested for different types of antioxidant assays. Although differences were observed in the net values of individual species all the species were found to be rich in protein, and carbohydrates and low in fat. Glucose was found to be the major monosaccharide. Predominance of UFA (65–70%) over SFA (30–35%) was observed in all the species with considerable amounts of other bioactive compounds. All the species showed higher effectiveness for antioxidant capacities. PMID:26199938

Antioxidant and antimicrobial capacity of several monofloral Cuban honeys and their correlation with color, polyphenol content and other chemical compounds.

PubMed

Alvarez-Suarez, Jose M; Tulipani, Sara; Díaz, Daimy; Estevez, Yadiley; Romandini, Stefania; Giampieri, Francesca; Damiani, Elisabetta; Astolfi, Paola; Bompadre, Stefano; Battino, Maurizio

2010-01-01

Several monofloral Cuban honeys were analyzed to determine their total phenolic, flavonoid, ascorbic acid, amino acid, protein and carotenoid contents as well as their radical-scavenging activity and antimicrobial capacities. The total phenolic, flavonoid and carotenoid contents varied considerably, and the highest values were obtained for Linen vine (Govania polygama (Jack) Urb) honey, which is classified as an amber honey. The highest amino acid content was found in Morning glory (Ipomoea triloba L.) while Liven vine had the highest protein content. Similarly Linen vine honey had the highest antioxidant activity while the lowest was found in Christmas vine (Turbina corymbosa (L.) Raf). Ascorbic acid was absent. Hydroxyl radical formation was studied by EPR and spin trapping, and it was found in all honeys tested. The antimicrobial activity was screened using two Gram-positive and Gram-negative bacteria. S. aureus was the most sensitive microorganism while Pseudomonas aeruginosa presented higher minimum active dilution values. Bacillus subtilis and Escherichia coli were both moderately sensitive to honey antimicrobial activity. A correlation between radical-scavenging activity and total phenolic content was found. Correlation existed also between color vs phenolics content, vs flavonoid content or between phenolic vs flavonoid. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

The effects of UV radiation during the vegetative period on antioxidant compounds and postharvest quality of broccoli (Brassica oleracea L.).

PubMed

Topcu, Yasin; Dogan, Adem; Kasimoglu, Zehra; Sahin-Nadeem, Hilal; Polat, Ersin; Erkan, Mustafa

2015-08-01

In this study, the effects of supplementary UV radiation during the vegetative period on antioxidant compounds, antioxidant activity and postharvest quality of broccoli heads during long term storage was studied. The broccolis were grown under three different doses of supplementary UV radiation (2.2, 8.8 and 16.4 kJ/m(2)/day) in a soilless system in a glasshouse. Harvested broccoli heads were stored at 0 °C in modified atmosphere packaging for 60 days. The supplementary UV radiation (280-315 nm) during the vegetative period significantly decreased total carotenoid, the chlorophyll a and chlorophyll b content but increased the ascorbic acid, total phenolic and flavonoid contents of broccolis. All supplementary UV treatments slightly reduced the antioxidant activity of the broccolis, however, no remarkable change was observed between 2.2 and 8.8 kJ/m(2) radiation levels. The sinigrin and glucotropaeolin contents of the broccolis were substantially increased by UV treatments. The prolonged storage period resulted in decreased ascorbic acid, total phenolic and flavonoid contents, as well as antioxidant activity. Discoloration of the heads, due to decreased chlorophyll and carotenoid contents, was also observed with prolonged storage duration. Glucosinolates levels showed an increasing tendency till the 45th day of storage, and then their levels started to decline. The weight loss of broccoli heads during storage progressively increased with storage time in all treatments. Total soluble solids, solids content and titratable acidity decreased continuously during storage. Titratable acidity was not affected by UV radiation doses during the storage time whereas soluble solids and solids content (dry matter) were significantly affected by UV doses. Supplementary UV radiation increased the lightness (L*) and chroma (C*) values of the broccoli heads. Pre-harvest UV radiation during vegetative period seems to be a promising tool for increasing the beneficial health components of broccolis. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Antioxidant and repellent activities of the essential oil from Colombian Triphasia trifolia (Burm. f.) P. Wilson.

PubMed

Jaramillo Colorado, Beatriz E; Martelo, Irina P; Duarte, Edisson

2012-06-27

The chemical composition of essential oils isolated from aerial parts of Triphasia trifolia (Burm. f.) P. Wilson was analyzed using hydrodistillation by GC-MS. The main constituents found were β-pinene (64.36%), (+)-sabinene (8.75%), hexadecanoic acid (6.03%), α-limonene (4.24%) and p-cymene (2.73%). The essential oil from T. trifolia shows high antioxidant potential (94.53%), an effect that is comparable with ascorbic acid (96.40%), used as standard. In addition, these oils had high repellent effects on the insect Tribolium castaneum Herbst (99% ± 1) at 0.2 μL/cm(2) after 2 h of exposure.

Synthesis, characterization and antioxidant study of N,N’-bis(2-chlorobenzamidothiocarbonyl)hydrazine

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

Firdausiah, Syadza; Hasbullah, Siti Aishah; Yamin, Bohari M.

2015-09-25

N,N’-bis(2-chlorobenzamidothiocarbonyl)hydrazine was synthesized from 2-chlorobenzoylisothiocyanate and hydrazine in acetone. The compound was characterized by infrared, {sup 1}H and {sup 13}C NMR, and UV-Vis spectroscopies. X-ray crystallography study showed the molecule adopt trans configuration at both N-N and C-N bonds. The compound showed high antioxidant activity, EC{sub 50} of 374.89 µM, compared to ascorbic acid (EC{sub 50} of 561.36 µM)

Dog rose (Rosa canina L.) as a functional ingredient in porcine frankfurters without added sodium ascorbate and sodium nitrite.

PubMed

Vossen, Els; Utrera, Mariana; De Smet, Stefaan; Morcuende, David; Estévez, Mario

2012-12-01

The effect of dog rose (Rosa canina L.; RC), rich in polyphenols and ascorbic acid, on lipid and protein oxidation, colour stability and texture of frankfurters was investigated. Four treatments were prepared: with 5 or 30 g/kg RC extract and without sodium ascorbate and sodium nitrite (5RC and 30RC, respectively), a positive control (with sodium ascorbate and sodium nitrite; PC) and a negative control (without sodium ascorbate, sodium nitrite or RC extract; NC). Hexanal values were much higher throughout storage in NC compared to RC and PC frankfurters (P<0.001). The RC extracts protected against protein oxidation, but not as efficiently as PC (P<0.05). In the RC treated frankfurters, lower a* values were measured compared to PC due to the lack of sodium nitrite. In conclusion, dog rose can act as a natural antioxidant in frankfurters, but not as full replacer for sodium nitrite. Copyright © 2012 Elsevier Ltd. All rights reserved.

Ascorbic acid enhances oxidative stress tolerance and biological control efficacy of Pichia caribbica against postharvest blue mold decay of apples.

PubMed

Li, Chaolan; Zhang, Hongyin; Yang, Qiya; Komla, Mahunu Gustav; Zhang, Xiaoyun; Zhu, Shuyun

2014-07-30

The effect of ascorbic acid (VC) on improving oxidative stress tolerance of Pichia caribbica and biocontrol efficacy against blue mold caused by Penicillium expansum on apples was investigated. P. caribbica showed susceptibility to the oxidative stress in vitro test, and 250 μg/mL VC treatment improved its oxidative stress tolerance. The higher viability exhibited by VC-treated yeast was associated with a lower intracellular ROS level. The activities of antioxidant enzymes of P. caribbica were improved by VC treatment, including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPX). Additionally, VC-treated yeast exhibited greater biocontrol activity against P. expansum and faster growth when stored at 25 and 4 °C, respectively, compared to the performance of the non-VC-treated yeast. In response to the VC treatment under oxidative stress, several differentially expressed proteins were identified in P. caribbica, and most of the poteins were confirmed to be related to basic metabolism. Therefore, the application of ascorbic acid is a useful approach to improve oxidative stress tolerance of P. caribbica and its biocontrol efficacy on apples.

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

PubMed

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

2016-04-01

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

Antioxidant properties of different edible mushroom species and increased bioconversion efficiency of Pleurotus eryngii using locally available casing materials.

PubMed

Mishra, K K; Pal, R S; Arunkumar, R; Chandrashekara, C; Jain, S K; Bhatt, J C

2013-06-01

Total phenolics, radical scavenging activity (RSA) on DPPH, ascorbic acid content and chelating activity on Fe(2+) of Pleurotus citrinopileatus, Pleurotus djamor, Pleurotus eryngii, Pleurotus flabellatus, Pleurotus florida, Pleurotus ostreatus, Pleurotus sajor-caju and Hypsizygus ulmarius have been evaluated. The assayed mushrooms contained 3.94-21.67 mg TAE of phenolics, 13.63-69.67% DPPH scavenging activity, 3.76-6.76 mg ascorbic acid and 60.25-82.7% chelating activity. Principal Component Analysis (PCA) revealed that significantly higher total phenolics, RSA on DPPH and growth/day was present in P. eryngii whereas P. citrinopileatus showed higher ascorbic acid and chelating activity. Agglomerative hierarchical clustering analysis revealed that studied mushroom species fall into two clusters; Cluster I included P. djamor, P. eryngii and P. flabellatus, while Cluster II included H. ulmarius, P. sajor-caju, P. citrinopileatus, P. ostreatus and P. florida. Enhanced yield of P. eryngii was achieved on spent compost casing material. Use of casing materials enhanced yield by 21-107% over non-cased substrate. Copyright © 2012 Elsevier Ltd. All rights reserved.

Study of the protective effect of ascorbic acid against the toxicity of stannous chloride on oxidative damage, antioxidant enzymes and biochemical parameters in rabbits.

PubMed

Yousef, M I; Awad, T I; Elhag, F A; Khaled, F A

2007-06-25

Stannous chloride (SnCl2) is a reducing chemical agent used in several man-made products. SnCl2 can generate reactive oxygen species (ROS). Therefore, the present study has been carried out to investigate the antioxidant action of l-ascorbic acid (AA) in minimizing SnCl2 toxicity on lipid peroxidation, antioxidant enzyme, and biochemical parameters in male New Zealand white rabbits. Animals were assigned to one of four treatment groups: 0mg AA and 0mg SnCl2/kg BW (control); 40 mg AA/kg BW; 20mg SnCl2/kg BW; 20mg SnCl2 plus 40 mg AA/kg BW. Rabbits were orally administered the respective doses every other day for 12 weeks. Results obtained showed that SnCl2 significantly (P<0.05) induced thiobarbituric acid-reactive substances (TBARS; the marker of lipid peroxidation) in plasma, while the activities of glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT), and the level of sulfhydryl groups (SH-group) were decreased (P<0.05) in blood plasma. Aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (AlP), acid phosphatase (AcP) and lactate dehydrogenase (LDH) activities were decreased (P<0.05). Stannous chloride significantly (P<0.05) increased the levels of plasma total lipid (TL), cholesterol, triglyceride (TG), low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL), glucose, urea and total bilirubin. On the other hand, the level of plasma high-density lipoprotein (HDL), total protein (TP), albumin (A) and globulin (G) were significantly (P<0.05) decreased. Ascorbic acid alone significantly decreased the levels of TBARS, lipids and urea, and increased the activities of GST, SOD and CAT, and the levels of SH-group and proteins. While the rest of the tested parameters were not affected. Also, the presence of AA with SnCl2 alleviated its harmful effects on most of the tested parameters. Therefore, the present results revealed that treatment with AA could minimize the toxic effects of stannous chloride.

Protective and antioxidative effect of rubropunctatin against oxidative protein damage induced by metal catalyzed reaction.

PubMed

Dhale, Mohan A; Javagal, Manjunatha; Puttananjaiah, Mohan-Kumari H

2018-05-03

Monascus purpureus is known to produce several coloured secondary metabolites. In this study, M. purpureus CFR 410-11 mutant fermented with rice was dried and extracted in hexane for purification of pigment. The purity of the isolated pigment was confirmed by different chromatography techniques. The spectroscopic analysis revealed its structural identity as rubropunctatin. The antioxidant potencies of isolated rubropunctatin were evaluated. Rubropunctatin scavenged 16% 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical and inhibited 20% superoxide generation at 8 μg/ml concentration. The multiple antioxidant abilities of rubropunctatin were evidenced by its ferric reducing capacity also. The oxidative damage of BSA protein was induced by the metal catalyzed oxidation (MCO) by Fe 2+ /H 2 O 2 . The protective effects of rubropunctatin and M. purpureus (MTCC-410 and CFR 410-11) extracts were compared with glutathione and ascorbic acid. The M. purpureus extracts and rubropunctatin inhibited the formation of carbonyl content and protein oxidation assayed by SDS-PAGE. Rubropunctatin (42-169 μM) efficiently inhibited the protein oxidation compared to glutathione (48-195 μM) and ascorbic acid (85-340 μM) by scavenging the superoxide and hydroxyl radical generated in the system. Copyright © 2018 Elsevier B.V. All rights reserved.

Dynamics in the concentrations of health-promoting compounds: lupeol, mangiferin and different phenolic acids during postharvest ripening of mango fruit.

PubMed

Vithana, Mekhala Dk; Singh, Zora; Johnson, Stuart K

2018-03-01

Mango fruit (Mangifera indica L.) is renowned for its pleasant taste and as a rich source of health beneficial compounds. The aim of this study was to investigate the changes in concentrations of health-promoting compounds, namely ascorbic acid, carotenoids, antioxidants, lupeol, mangiferin, total phenols and individual phenolic acids, as well as ethylene production and respiration rates during climacteric ripening in 'Kensington Pride' and 'R2E2' mango fruit. The climacteric ethylene and respiration peaks were noted on the third day of the fruit ripening period. The concentrations of total carotenoids in the pulp, total antioxidants in both pulp and peel, and total phenols of the peel, lupeol and mangiferin were significantly elevated, whereas the concentration of ascorbic acid declined during post-climacteric ripening. Gallic, chlorogenic and vanillic acids were identified as the major phenolic acids in both pulp and peel of 'Kensington Pride' and 'R2E2' mangoes. The concentrations of phenolic acids (gallic, chlorogenic, vanillic, ferulic and caffeic acids) also increased during the post-climacteric phase. The concentrations of all phenolic compounds were several-fold higher in the peel than pulp. Mangoes at post-climacteric ripening phase offer the highest concentrations of health-promoting compounds. Peel, at this stage of fruit ripening, could be exploited as a good source for extraction of these compounds. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Hemolysis in a patient with alkaptonuria and chronic kidney failure.

PubMed

Heng, Anne-Elisabeth; Courbebaisse, Marie; Kemeny, Jean Louis; Matesan, Raluca; Bonniol, Claude; Deteix, Patrice; Souweine, Bertrand

2010-07-01

In alkaptonuria, the absence of homogentisic acid oxidase results in the accumulation of homogentisic acid (HGA) in the body. Fatal disease cases are infrequent, and death often results from kidney or cardiac complications. We report a 24-year-old alkaptonuric man with severe decreased kidney function who developed fatal metabolic acidosis and intravascular hemolysis. Hemolysis may have been caused by rapid and extensive accumulation of HGA and subsequent accumulation of plasma soluble melanins. Toxic effects of plasma soluble melanins, their intermediates, and reactive oxygen side products are increased when antioxidant mechanisms are overwhelmed. A decrease in serum antioxidative activity has been reported in patients with chronic decreased kidney function. However, despite administration of large doses of an antioxidant agent and ascorbic acid and intensive kidney support, hemolysis and acidosis could not be brought under control and hemolysis led to the death of the patient.

Physico-Chemical Characterization, Bioactive Compounds and Antioxidant Activity of Malay Apple [Syzygium malaccense (L.) Merr. & L.M. Perry

PubMed Central

Nunes, Polyana Campos; Aquino, Jailane de Souza; Rockenbach, Ismael Ivan; Stamford, Tânia Lúcia Montenegro

2016-01-01

The purpose of this study was to evaluate the physico-chemical characteristics, bioactive compounds and antioxidant activity of Malay apple fruit (Syzygium malaccense) grown in Brazil with regard to the geographical origin and its peel fractions and edible portion analyzed independently. Fruit diameter, weight, yield, and centesimal composition, ascorbic acid, reductive sugars, total soluble solids, pH and fiber content were determined. Total phenolics (1293 mg gallic acid equivalent/100 g) and total anthocyanins (1045 mg/100 g) contents were higher in the peel, with the major anthocyanin identified using HPLC-DAD-MS/MS as cyanidin 3-glucoside. Higher values for DPPH antiradical scavenging activity (47.52 μMol trolox equivalent antioxidant capacity/g) and Ferric Reducing Antioxidant Potential (FRAP, 0.19 mM ferreous sulfate/g) were also observed in the peel fraction. All extracts tested showed the ability to inhibit oxidation in the β-carotene/linoleic acid system. This study highlights the potential of Malay apple fruit as a good source of antioxidant compounds with potential benefits to human health. PMID:27352306

Antioxidant potential of different grape cultivars against Fenton-like reagent-induced liver damage ex-vivo.

PubMed

Singha, Indrani; Das, Subir Kumar

2014-10-01

The phytochemicals present in the grapes are responsible for nutraceutical and health benfits due to their antioxidant properties. These phytochemicals, however, vary greatly among different cultivars. In this study, we evaluated the antioxidant potential and protective role of four different Indian grape (Vitis vinifera) cultivars extracts, namely Flame seedless (Black grapes), Kishmish chorni (Black with reddish brown), Red globe (Red) and Thompson seedless mutant (Sonaka, Green) against the Fenton-like reagent (200 μmole H2O2, 2 mmole ascorbate, 25 μmole FeSO4)-induced liver damage. Non-enzymatic antioxidants, such as glutathione (GSH) levels and activities of antioxidant enzymes, such as glutathione S-transferase (GST) and superoxide dismutase (SOD), as well as total antioxidant capacity (TAC) were highest in the grape seed, followed by skin and pulp. Among edible parts of different cultivars, skin of Flame seedless (Black) cultivar showed highest antioxidant potential, while the Thompson seedless the least potential. These antioxidants were found to be significantly (P < 0.01) correlated with the levels of total phenol, flavonoids and ascorbic acid. Fenton-like reagent treatment significantly (P < 0.001) decreased GSH content by 39.1% and activities of catalase (CAT) by 43.2% and glutathione reductase (GR) by 60%, while increasing thiobarbituric acid reactive substances (TBARS) and nitric oxide levels by 2.13-fold and 0.64-fold, respectively and GST activity by 0.81-fold. Pre-treatment with grape seed extracts showed the best hepatoprotective action against Fenton-like reagent-induced damage, followed by the extracts of skin and pulp of any cultivar. Thus, our study showed the significant amounts of antioxidants were in grape seed, followed by its skin and pulp, which varied among the cultivars and was associated with the protective action of grape extracts against Fenton-like reagent-induced liver damage ex-vivo.

Comparison of the contents of various antioxidants of sea buckthorn berries using CE.

PubMed

Gorbatsova, Jelena; Lõugas, Tiina; Vokk, Raivo; Kaljurand, Mihkel

2007-11-01

The increased interest in sea buckthorn (Hippophae rhamnoides L.) made it possible to investigate the antioxidant content in it. To address this issue, the presence of following antioxidant compounds were analyzed: trans-resveratrol, catechin, myricetin, quercetin, p-coumaric acid, caffeic acid, L-ascorbic acid (AA), and gallic acid (linear range of 50-150 micromol/L) in six different varieties of sea buckthorn berries extracts (sea buckthorn varieties: "Trofimovskaja (TR)," "Podarok Sadu (PS)," and "Avgustinka (AV),") received from two local Estonian companies. Trans-Resveratrol, catechin, AA, myricetin, and quercetin were found in extracts of sea buckthorn. Moreover, AA, myricetin, and quercetin contents were quantified. The biggest average AA content was found in TR (740 mg/100 g of dried berries, respectively). Furthermore, the same varieties gave the biggest quercetin content 116 mg/100 g of dried berries, respectively. For analysis, CZE was used and the results were partly validated by HPLC. Statistically no big differences in levels of antioxidants were consistently found in different varieties of sea buckthorn extracts investigated in this work.

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

PubMed

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

2017-07-01

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

Antioxidant-restricted diet reduces plasma nonesterified fatty acids in trained athletes.

PubMed

Watson, Trent A; Blake, Robert J; Callister, Robin; Garg, Manohar L

2005-04-01

Nonesterified FA (NEFA) are a major fuel source for humans at rest and during moderate exercise. The effect of dietary antioxidant restriction on plasma NEFA levels and exercise performance in trained athletes was examined. Seventeen athletes followed a 2-wk restricted-antioxidant (R-AO) diet, which resulted in a threefold reduction in antioxidant intake (ascorbic acid, 139 to 49 mg; beta-carotene, 5093 to 1142 microg) and a significant (P = 0.001) reduction in the plasma NEFA. The amount and types of fat consumed were not different between the R-AO and habitual diets. Exercise time to exhaustion was not affected by the R-AO diet, but rating of perceived exertion (RPE) was significantly (P = 0.03) elevated. The increase in RPE may have occurred as a result of the R-AO diet and subsequent reduction in plasma NEFA; however, further research is required to confirm this conclusion.

Modified atmosphere packaging for fresh-cut ‘Kent’ mango under common retail display conditions

USDA-ARS?s Scientific Manuscript database

A modified atmosphere package (MAP) was designed to optimize the quality and shelf-life of fresh-cut ‘Kent’ mango during exposure to common retail display conditions. The synergism between the MAP system and an antioxidant treatment (calcium ascorbate and citric acid) was also investigated. Mango sl...

Intransience of functional components and distinctive properties of amla (Indian gooseberry) ice cream during short-term storage.

PubMed

Goraya, Rajpreet Kaur; Bajwa, Usha

2018-05-01

Inclusion of processed amla have been found to enhance the functional properties and nutritional value of ice cream by augmenting the fiber content, total phenols, tannins, ascorbic acid and antioxidant activity. The present investigation assessed the changes in these constituents, color values (L, a* and b*), melting rate, sensory scores and microbiological quality of ice cream containing amla shreds, pulp, preserve, candy and powder during 60 days' storage at - 18 to - 20 °C. The total solids increased slightly whereas the antioxidant activity, total phenols, ascorbic acid and tannins decreased on storage. The L values declined whereas a* and b* values amplified, the rate of change being highest in candy containing sample followed by preserve. The first drip time of all the samples increased whereas melting rate decreased. The overall acceptability scores declined non significantly. Standard plate count of all the ice cream samples decreased significantly whereas yeast and molds were not detected throughout the storage. The psychrophiles were not spotted up to 30 days, thereafter, a small increase was observed.

Implications of mycosporine-like amino acid and antioxidant defenses in UV-B radiation tolerance for the algae species Ptercladiella capillacea and Gelidium amansii.

PubMed

Lee, Tse-Min; Shiu, Chia-Tai

2009-02-01

Ultraviolet-B (UV-B) radiation (0.5, 1.0, 1.5, and 3.0Wm(-2)) induced higher H(2)O(2) production and lipid peroxidation in alga Gelidium amansii inhabiting in lower subtidal regions than upper subtidal alga Ptercladiella capillacea. Compared to G. amansii, mycosporine-like amino acid (MAA) concentration in P. capillacea was higher and can be increased by 0.5-1.0Wm(-2) UV-B, while carotenoid concentration was lower but also increased by 1.5-3.0Wm(-2) UV-B. UV-B increased ascorbate concentration, but to a higher degree in P. capillacea. UV-B decreased glutathione concentration, but to a higher degree in G. amansii. UV-B increased ascorbate peroxidase (APX) and glutathione reductase (GR) activities in P.capillacea but decreased them in G. amansii. UV-B increased superoxide dismutase and catalase activities, but to a higher degree in G. amansii. So, G. amansii suffered greater oxidative stress from UV-B radiation. P. capillacea can effectively reduce UV-B sensitivity by increasing sunscreen ability and antioxidant defense capacity.

Organically grown tomato (Lycopersicon esculentum Mill.): bioactive compounds in the fruit and infection with Phytophthora infestans.

PubMed

Mohammed, Afrah E; Smit, Inga; Pawelzik, Elke; Keutgen, Anna J; Horneburg, Bernd

2012-05-01

Tomato fruits are characterized by a good nutritional profile, including different bioactive compounds such as carotenoids, phenolic compounds and ascorbic acid. The objective of this study was to analyze the content of bioactive compounds in the fruit and the infection by Phytophthora infestans of 28 tomato genotypes from organic outdoor production. The relationship between bioactive compounds in the fruit and infection with P. infestans was estimated. Field experiments were carried out in 2004 and 2005 at two locations in central Germany. Significant variation among genotypes, locations and years was observed for the content of lycopene, ascorbic acid, total phenolic compounds, antioxidant capacity and the infection level of P. infestans. Antioxidant capacity seemed to be influenced mainly by the phenolics and was highest in small fruits, which were less infected with P. infestans. The large genetic variation among tomato genotypes for the content of bioactive compounds in their fruit allows for selection gains. None of the investigated bioactive compounds can be recommended for the indirect selection for increased field resistance against P. infestans. Copyright © 2011 Society of Chemical Industry.

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

PubMed

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

2015-01-01

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

Effect of different cooking methods on color, phytochemical concentration, and antioxidant capacity of raw and frozen brassica vegetables.

PubMed

Pellegrini, Nicoletta; Chiavaro, Emma; Gardana, Claudio; Mazzeo, Teresa; Contino, Daniele; Gallo, Monica; Riso, Patrizia; Fogliano, Vincenzo; Porrini, Marisa

2010-04-14

This study evaluated the effect of common cooking practices (i.e., boiling, microwaving, and basket and oven steaming) on the phytochemical content (carotenoids, chlorophylls, glucosinolates, polyphenols, and ascorbic acid), total antioxidant capacity (TAC), and color changes of three generally consumed Brassica vegetables analyzed fresh and frozen. Among cooking procedures, boiling determined an increase of fresh broccoli carotenoids and fresh Brussels sprout polyphenols, whereas a decrease of almost all other phytochemicals in fresh and frozen samples was observed. Steaming procedures determined a release of polyphenols in both fresh and frozen samples. Microwaving was the best cooking method for maintaining the color of both fresh and frozen vegetables and obtaining a good retention of glucosinolates. During all cooking procedures, ascorbic acid was lost in great amount from all vegetables. Chlorophylls were more stable in frozen samples than in fresh ones, even though steaming methods were able to better preserve these compounds in fresh samples than others cooking methods applied. The overall results of this study demonstrate that fresh Brassica vegetables retain phytochemicals and TAC better than frozen samples.

Screening of the antioxidative properties and total phenolic contents of three endemic Tanacetum subspecies from Turkish flora.

PubMed

Tepe, Bektas; Sokmen, Atalay

2007-11-01

Methanolic extracts of three different Tanacetum subspecies [Tanacetum densum (Lab.) Schultz Bip. subsp. sivasicum Hub-Mor and Grierson, Tanacetum densum (Lab.) Schultz Bip. subsp. eginense Heywood and Tanacetum densum (Lab.) Schultz Bip. subsp. amani Heywood] which are endemic to Turkish flora were screened for their possible antioxidant activities by two complementary test systems namely DPPH free radical scavenging and beta-carotene/linoleic acid. In DPPH system, the most active plant was T. densum subsp. amani with an IC(50) value of 69.30+/-0.37 microg/ml. On the other hand, T. densum subsp. sivasicum exerted greater antioxidant activity than those of other subspecies in beta-carotene/linoleic acid system (79.10%+/-1.83). Antioxidant activities of BHT, curcumine and ascorbic acid were also determined as positive controls in parallel experiments. Total phenolic constituents of the extracts of Tanacetum subspecies were performed employing the literature methods involving Folin-Ciocalteu reagent and gallic acid as standard. The amount of total phenolics was highest in subsp. sivasicum (162.33+/-3.57 microg/mg), followed by subsp. amani (158.44+/-2.17 microg/mg). Especially, a positive correlation was observed between total phenolic content and antioxidant activity of the extracts.

Effect of edible coatings on bioactive compounds and antioxidant capacity of tomatoes at different maturity stages.

PubMed

Dávila-Aviña, Jorge E; Villa-Rodríguez, José A; Villegas-Ochoa, Mónica A; Tortoledo-Ortiz, Orlando; Olivas, Guadalupe I; Ayala-Zavala, J Fernando; González-Aguilar, Gustavo A

2014-10-01

This work evaluated the effect of carnauba and mineral oil coatings on the bioactive compounds and antioxidant capacity of tomato fruits (cv. "Grandela"). Carnauba and mineral oil coatings were applied on fresh tomatoes at two maturity stages (breaker and pink) over 28 day of storage at 10 °C was evaluated. Bioactive compound and antioxidant activity assays included total phenols, total flavonoids, ascorbic acid (ASA), lycopene, DPPH radical scavenging activity (%RSA), trolox equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity assay (ORAC). The total phenolic, flavonoid and lycopene contents were significantly lower for coated fruit than control fruits. However, ascorbic acid content was highest in fruits treated with carnauba, followed by mineral oil coating and control fruits. The ORAC values were highest in breaker tomatoes coated with carnauba wax, followed by mineral oil-coated fruits and controls. No significant differences in ORAC values were observed in pink tomatoes. % RSA and TEAC values were higher for controls than for coated fruit. Edible coatings preserve the overall quality of tomatoes during storage without affecting the nutritional quality of fruit. We found that the physiological response to the coatings is in function of the maturity stage of tomatoes. The information obtained in this study support to use of edible coating as a safe and good alternative to preserve tomato quality, and that the changes of bioactive compounds and antioxidant activity of tomato fruits, was not negatively affected. This approach can be used by producers to preserve tomato quality.

Antioxidant and Antifungal Activity of Extracts of the Aerial Parts of Thymus capitatus (L.) Hoffmanns Against Four Phytopathogenic Fungi of Citrus sinensis

PubMed Central

Tabti, Leila; Dib, Mohammed El Amine; Gaouar, Nassira; Samira, Bouayad; Tabti, Boufeldja

2014-01-01

Background: Many medicinal plants from the Lamiaceae family can be easily found in Algeria. These plants have been used as traditional medicines by local ethnic groups. Thymus capitatus is known in Algeria as "Zaatar" and has been commonly used as a spice, and reported to have many biological effects. Objectives: This paper focused on the assessment of the antioxidant potential and antifungal activity of essential oil and solvent extracts of T. capitatus against the growth of certain fungi. Materials and Methods: Essential oil, ethanol and hexane extracts of T. capitatus were tested for their antioxidant and antifungal activities. The 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay was used to determine the free radical quenching capacity. Antifungal activity was assessed using the radial growth technique. Results: DPPH free radical scavenging effect of the extracts was compared with standard antioxidant ascorbic acid and showed significant results. The ethanol extract showed high activity at the concentration of 80 g/mL, but less than the standard ascorbic acid. The essential oil was effective against all the fungi used in the experiment. The highest inhibitory effect on the growth of Aspergillus niger, Aspergillus oryzae, Penicillium digitatum, and Fusarium solani was exhibited by the essential oil at concentrations between 0.1 and 0.5 μg/mL. Conclusions: These findings demonstrated that ethanol extract obtained from T. capitatus is a potential source of natural antioxidant, while the essential oil extract can be exploited as an ideal alternative to synthetic fungicides for use in the treatment of many fungal phytopathogens. PMID:24644439

Antioxidant status and smoking habits: relationship with diet.

PubMed

Jain, A; Agrawal, B K; Varma, M; Jadhav, A A

2009-06-01

The present study was conducted to assess the association between smoking, dietary intake of antioxidants and plasma indices of oxidative stress and antioxidant defences in male smokers (cigarette and bidi smokers). The study sample consisted of 100 healthy men, including 50 non-smokers and 50 smokers, who were subclassified into 25 cigarette smokers and 25 bidi smokers, aged 18-55 years. Erythrocyte superoxide dismutase and plasma ascorbic acid were measured as antioxidants and erythrocyte malondialdehyde as an oxidative stress index, by colorimetric methods. Smokers ate less fruits and vegetables than non-smokers, leading to them having a lower antioxidant level. Erythrocyte superoxide dismutase was significantly lower in cigarette smokers (0.193 U/mgP, p-value is less than 0.05) and bidi smokers (0.169 U/mgP, p-value is less than 0.001) as compared to non-smokers (0.231 U/mgP). Plasma ascorbic acid was also significantly lower in cigarette smokers (1.45 mg/100 ml, p-value is less than 0.05) as well as in bidi smokers (1.38 mg/100 ml, p-value is less than 0.001) as compared to non-smokers (1.73 mg/100 ml). There was a significant increase in erythrocyte malondialdehyde concentration levels in cigarette smokers (171.47 micromol/gHb, p-value is less than 0.05) as well as in bidi smokers (231.04 micromol/gHb, p-value is less than 0.001) as compared to non-smokers (127.30 micromol/gHb). These results provide enough evidence of increased oxidative stress and a compromised antioxidant defence system in smokers, and they are more profound in bidi smokers than in those smoking cigarettes. This study also revealed that the diet and nutrient intake of smokers are different from that of non-smokers.

Oxidation management of white wines using cyclic voltammetry and multivariate process monitoring.

PubMed

Martins, Rui C; Oliveira, Raquel; Bento, Fatima; Geraldo, Dulce; Lopes, Vitor V; Guedes de Pinho, Paula; Oliveira, Carla M; Silva Ferreira, Antonio C

2008-12-24

The development of a fingerprinting strategy capable to evaluate the "oxidation status" of white wines based on cyclic voltammetry is proposed here. It is known that the levels of specific antioxidants and redox mechanisms may be evaluated by cyclic voltammetry. This electrochemical technique was applied on two sets of samples. One group was composed of normal aged white wines and a second group obtained from a white wine forced aging protocol with different oxygen, SO(2), pH, and temperature regimens. A study of antioxidant additions, namely ascorbic acid, was also made in order to establish a statistical link between voltammogram fingerprints and chemical antioxidant substances. It was observed that the oxidation curve presented typical features, which enables sample discrimination according to age, oxygen consumption, and antioxidant additions. In fact, it was possible to place the results into four significant orthogonal directions, compressing 99.8% of nonrandom features. Attempts were made to make voltammogram fingerprinting a tool for monitoring oxidation management. For this purpose, a supervised multivariate control chart was developed using a control sample as reference. When white wines are plotted onto the chart, it is possible to monitor the oxidation status and to diagnose the effects of oxygen regimes and antioxidant activity. Finally, quantification of substances implicated in the oxidation process as reagents (antioxidants) and products (off-flavors) was tried using a supervised algorithmic the partial least square regression analysis. Good correlations (r > 0.93) were observed for ascorbic acid, Folin-Ciocalteu index, total SO(2), methional, and phenylacetaldehyde. These results show that cyclic voltammetry fingerprinting can be used to monitor and diagnose the effects of wine oxidation.

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

PubMed

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

2003-02-01

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

Identification and quantification of antioxidant components of honeys from various floral sources.

PubMed

Gheldof, Nele; Wang, Xiao-Hong; Engeseth, Nicki J

2002-10-09

Little is known about the individual components of honey that are responsible for its antioxidant activity. The present study was carried out to characterize the phenolics and other antioxidants present in honeys from seven floral sources. Chromatograms of the phenolic nonpolar fraction of the honeys indicated that most honeys have similar but quantitatively different phenolic profiles. Many of the flavonoids and phenolic acids identified have been previously described as potent antioxidants. A linear correlation between phenolic content and ORAC activity was demonstrated (R(2) = 0.963, p < 0.0001). Honeys were separated by solid-phase extraction into four fractions for sugar removal and separation based on solubility to identify the relative contribution of each fraction to the antioxidant activity of honey. Antioxidant analysis of the different honey fractions suggested that the water-soluble fraction contained most of the antioxidant components. Specific water-soluble antioxidant components were quantified, including protein; gluconic acid; ascorbic acid; hydroxymethylfuraldehyde; and the combined activities of the enzymes glucose oxidase, catalase and peroxidase. Of these components, a significant correlation could be established only between protein content and ORAC activity (R(2) = 0.674, p = 0.024). In general, the antioxidant capacity of honey appeared to be a result of the combined activity of a wide range of compounds including phenolics, peptides, organic acids, enzymes, Maillard reaction products, and possibly other minor components. The phenolic compounds contributed significantly to the antioxidant capacity of honey but were not solely responsible for it.

A universally calibrated microplate ferric reducing antioxidant power (FRAP) assay for foods and applications to Manuka honey.

PubMed

Bolanos de la Torre, Amparo Angelica S; Henderson, Terence; Nigam, Poonam Singh; Owusu-Apenten, Richard K

2015-05-01

The ferric reducing antioxidant power (FRAP) assay was recently adapted to a microplate format. However, microplate-based FRAP (mFRAP) assays are affected by sample volume and composition. This work describes a calibration process for mFRAP assays which yields data free of volume effects. From the results, the molar absorptivity (ε) for the mFRAP assay was 141,698 M(-1) cm(-1) for gallic acid, 49,328 M(-1) cm(-1) for ascorbic acid, and 21,606 M(-1) cm(-1) for ammonium ferrous sulphate. The significance of ε (M(-1) cm(-1)) is discussed in relation to mFRAP assay sensitivity, minimum detectable concentration, and the dimensionless FRAP-value. Gallic acid showed 6.6 mol of Fe(2+) equivalents compared to 2.3 mol of Fe(+2) equivalents for ascorbic acid. Application of the mFRAP assay to Manuka honey samples (rated 5+, 10+, 15+, and 18+ Unique Manuka Factor; UMF) showed that FRAP values (0.54-0.76 mmol Fe(2+) per 100g honey) were strongly correlated with UMF ratings (R(2)=0.977) and total phenols content (R(2) = 0.982)whilst the UMF rating was correlated with the total phenols (R(2) = 0.999). In conclusion, mFRAP assay results were successfully standardised to yield data corresponding to 1-cm spectrophotometer which is useful for quality assurance purposes. The antioxidant capacity of Manuka honey was found to be directly related to the UMF rating. Copyright © 2014 Elsevier Ltd. All rights reserved.

DNA Damage Protecting Activity and Antioxidant Potential of Launaea taraxacifolia Leaves Extract.

PubMed

Adinortey, Michael Buenor; Ansah, Charles; Weremfo, Alexander; Adinortey, Cynthia Ayefoumi; Adukpo, Genevieve Etornam; Ameyaw, Elvis Ofori; Nyarko, Alexander Kwadwo

2018-01-01

The leaf extract of Launaea taraxacifolia commonly known as African Lettuce is used locally to treat dyslipidemia and liver diseases, which are associated with oxidative stress. Methanol extract from L. taraxacifolia leaves was tested for its antioxidant activity and its ability to protect DNA from oxidative damage. In vitro antioxidant potential of the leaf extract was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide (NO), and hydroxyl (OH) radical scavenging assays. Ferric reducing power, total antioxidant capacity (TAC), metal chelating, and anti-lipid peroxidation ability of the extract were also examined using gallic acid, ascorbic acid, citric acid, and ethylenediaminetetraacetic acid as standards. L. taraxacifolia leaves extract showed antioxidant activity with IC 50 values of 16.18 μg/ml (DPPH), 123.3 μg/ml (NO), 128.2 μg/ml (OH radical), 97.94 μg/ml (metal chelating), 80.28 μg/ml (TAC), and 23 μg/ml (anti-lipid peroxidation activity). L. taraxacifolia leaves extract exhibited a strong capability for DNA damage protection at 20 mg/ml concentration. These findings suggest that the methanolic leaf extract of L. taraxacifolia could be used as a natural antioxidant and also as a preventive therapy against diseases such as arteriosclerosis associated with DNA damage.

Characterization of bioactive compounds in Tunisian bitter orange (Citrus aurantium L.) peel and juice and determination of their antioxidant activities.

PubMed

Jabri Karoui, Iness; Marzouk, Brahim

2013-01-01

Citrus aurantium peel and juice aroma compounds were investigated by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), whereas phenolic compounds analysis was performed by reversed-phase high-performance liquid chromatography (RP-HPLC). Limonene was the major volatile compound of bitter orange peel (90.25%) and juice (91.61%). HPLC analysis of bitter orange peel and juice methanolic extracts indicated that phenolic acids constitute their main phenolic class representing 73.80% and 71.25%, respectively, followed by flavonoids (23.02% and 23.13%, resp.). p-Coumaric and ferulic acids were the most abundant phenolic compounds representing 24.68% and 23.79%, respectively, in the peel, while the juice contained 18.02% and 19.04%, respectively. The antioxidant activities of bitter orange peel and juice methanolic extracts have been evaluated using four in vitro assays, and the results were compared with the standard antioxidants (BHT, BHA, and ascorbic acid). Our findings demonstrated that Citrus aurantium peel and juice possess antioxidant activities which were less effective than those of antioxidant standards. Both extracts may be suggested as a new potential source of natural antioxidant.

Characterization of Bioactive Compounds in Tunisian Bitter Orange (Citrus aurantium L.) Peel and Juice and Determination of Their Antioxidant Activities

PubMed Central

Jabri karoui, Iness; Marzouk, Brahim

2013-01-01

Citrus aurantium peel and juice aroma compounds were investigated by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), whereas phenolic compounds analysis was performed by reversed-phase high-performance liquid chromatography (RP-HPLC). Limonene was the major volatile compound of bitter orange peel (90.25%) and juice (91.61%). HPLC analysis of bitter orange peel and juice methanolic extracts indicated that phenolic acids constitute their main phenolic class representing 73.80% and 71.25%, respectively, followed by flavonoids (23.02% and 23.13%, resp.). p-Coumaric and ferulic acids were the most abundant phenolic compounds representing 24.68% and 23.79%, respectively, in the peel, while the juice contained 18.02% and 19.04%, respectively. The antioxidant activities of bitter orange peel and juice methanolic extracts have been evaluated using four in vitro assays, and the results were compared with the standard antioxidants (BHT, BHA, and ascorbic acid). Our findings demonstrated that Citrus aurantium peel and juice possess antioxidant activities which were less effective than those of antioxidant standards. Both extracts may be suggested as a new potential source of natural antioxidant. PMID:23841062

Release of the antioxidants ascorbate and urate from a nitrergically-innervated smooth muscle.

PubMed

Lilley, E; Gibson, A

1997-12-01

1. The main object of the present study was to determine whether ascorbate, an antioxidant which has been shown to protect nitric oxide (NO) from attack by scavenger molecules, might be released from nitrergically-innervated smooth muscle; ascorbate release from the rat anococcygeus was measured by use of h.p.l.c. with electrochemical detection. 2. Incubation of rat anococcygeus muscles in normal physiological salt solution (PSS; 30 min) resulted in release of ascorbate into the bathing medium (7.7 +/- 0.9 nmol g-1 tissue). This release was increased by 96% when muscles were incubated in high K+ (70 mM) PSS. The resting release of ascorbate was unaffected by tetrodotoxin (TTX; 1 microM), omega-conotoxin GVIA (10 nM) or omission of calcium ions from the PSS (with addition of 0.2 mM EGTA), but all three procedures attenuated the increased release observed under depolarizing conditions. Resting release of ascorbate was unaffected by glutamate (100 microM), aspartate (100 microM), gamma-aminobutyric acid (100 microM) or carbachol (50 microM). 3. A second h.p.l.c. peak, which always preceded the ascorbate peak, was identified as urate. Urate release from the anococcygeus, following 30 min incubation in normal PSS, was 64.6 +/- 12.7 nmol g-1 tissue but, unlike ascorbate, urate release was unchanged in high K+ PSS. In functional experiments, urate (100-400 microM) partially protected NO (15 microM)-induced relaxations of the rat anococcygeus from inhibition by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO; 50 microM), but not from inhibition by hydroquinone or duroquinone (both 100 microM). 4. Muscles chemically sympathectomized with 6-hydroxydopamine (6-OHDA, 500 microM; 2 h) still exhibited release of ascorbate (2.5 +/- 0.4 nmol g-1 tissue) and urate (22.2 +/- 2.9 nmol g-1 tissue); in both cases the release was similar to that observed in time-matched control tissues not exposed to 6-OHDA. High K+ PSS produced a TTX-sensitive increase in release of ascorbate, but not urate, from 6-OHDA-treated muscles. 5. The results demonstrate that significant amounts of ascorbate and urate are released from the rat anococcygeus muscle. Ascorbate, but not urate, release appears to be enhanced by activation of nerves which are resistant to 6-OHDA pretreatment. Since both antioxidants can protect NO from attack by scavenger molecules, their release in nitrergically-innervated tissues may be important for the provision of the correct redox environment to allow NO to fulfill its proposed neurotransmitter role.

How the multiple antioxidant properties of ascorbic acid affect lipid oxidation in oil-in-water emulsions.

PubMed

Uluata, Sibel; McClements, D Julian; Decker, Eric A

2015-02-18

Lipid oxidation is a serious problem for oil-containing food products because it negatively affects shelf life and nutritional composition. An antioxidant strategy commonly employed to prevent or delay oxidation in foods is to remove oxygen from the closed food-packaging system. An alternative technique is use of an edible oxygen scavenger to remove oxygen within the food. Ascorbic acid (AA) is a particularly promising antioxidant because of its natural label and multiple antioxidative functions. In this study, AA was tested as an oxygen scavenger in buffer and an oil-in-water (O/W) emulsion. The effects of transition metals on the ability of AA to scavenge oxygen were determined. Headspace oxygen decrease less than 1% in the medium-chain triacylglycerol (MCT) O/W emulsion system (pH 3 and 7). AA was able to almost completely remove dissolved oxygen (DO) in a buffered solution. Transition metals (Fe(2+) and Cu(+)) significantly accelerated the degradation of AA; however, iron and copper only increased DO depletion rates, by 10.6-16.4% from day 1 to 7, compared to the control. AA (2.5-20 mM) decreased DO in a 1% O/W emulsion system 32.0-64.0% and delayed the formation of headspace hexanal in the emulsion from 7 to over 20 days. This research shows that, when AA is used in an O/W emulsion system, oxidation of the emulsion system can be delay by multiple mechanisms.

Synergistic effects of plant defense elicitors and Trichoderma harzianum on enhanced induction of antioxidant defense system in tomato against Fusarium wilt disease.

PubMed

Zehra, Andleeb; Meena, Mukesh; Dubey, Manish Kumar; Aamir, Mohd; Upadhyay, R S

2017-11-02

Plant defense against their pathogens can be induced by a complex network of different inducers. The present study investigates the synergistic effect of Trichoderma harzianum, exogenous salicylic acid (SA) and methyl jasmonate (MeJA) over the response and regulation of the antioxidant defense mechanisms and lipid peroxidation in tomato plants against Fusarium wilt disease. In the present work, tomato plants were infected by Fusarium oxysporum f. sp. lycopersici 3 days after inoculated with T. harzianum and/or sprayed daily for 3 days with chemical inducers (SA and MeJA). Plants were analysed at 0, 24, 48, 72 and 96 h after inoculation with Fusarium oxysporum f. sp. lycopersici. Infection of tomato plants by pathogen led to strong reduction in the dry weight of roots and shoots with the enhanced concentration of H 2 O 2 and varying degree of lipid peroxidation. Concurrently, exogenous SA, when applied with pathogen greatly enhanced H 2 O 2 content as well as activities of antioxidant enzymes except catalase (CAT) and ascorbate peroxidase (APx). The pathogen challenged plants pretreated with T. harzianum and MeJA together exhibited less lipid peroxidation and as well as the elevated level of ascorbic acid and enhanced activities of antioxidant enzymes. All applied treatments protected tomato seedlings against Fusarium wilt disease but the percentage of protection was found higher in plants pretreated with the combination of T. harzianum and chemical inducers.

Cooking methods employing natural anti-oxidant food additives effectively reduced concentration of nephrotoxic and carcinogenic aristolochic acids in contaminated food grains.

PubMed

Li, Weiwei; Chan, Chi-Kong; Wong, Yee-Lam; Chan, K K Jason; Chan, Ho Wai; Chan, Wan

2018-10-30

Emerging evidence suggests that aristolochic acids (AA) produced naturally by a common weed Aristolochia clematitis in the cultivation fields is contaminating the food products in Balkan Peninsula and acting as the etiological agent in the development of Balkan endemic nephropathy. In this study, we investigated the combined use of natural anti-oxidative "food additives" and different cooking methods to find a solution for the widespread contamination of AA in food products. The results indicated that the addition of healthy dietary supplements (such as cysteine, glutathione, ascorbic acid, citric acid and magnesium) during cooking, is a highly efficient method in lowering the concentration of AA in the final food products. Because previous observation indicated one of the toxicological mechanisms by which AA exert its toxicity is to induce oxidative stress in internal organs, it is anticipated that these added anti-oxidants will also help to attenuate the nephrotoxicity of AA. Copyright © 2018 Elsevier Ltd. All rights reserved.

Antioxidative responses of Ocimum basilicum to sodium chloride or sodium sulphate salinization.

PubMed

Tarchoune, I; Sgherri, C; Izzo, R; Lachaal, M; Ouerghi, Z; Navari-Izzo, F

2010-09-01

Soils and ground water in nature are dominated by chloride and sulphate salts. There have been several studies concerning NaCl salinity, however, little is known about the Na(2)SO(4) one. The effects on antioxidative activities of chloride or sodium sulphate in terms of the same Na(+) equivalents (25 mM Na(2)SO(4) and 50 mM NaCl) were studied on 30 day-old plants of Ocimum basilicum L., variety Genovese subjected to 15 and 30 days of treatment. Growth, thiobarbituric acid reactive substances (TBARS), relative ion leakage ratio (RLR), hydrogen peroxide (H(2)O(2)), ascorbate and glutathione contents as well as the activities of ascorbate peroxidase (APX, EC 1.11.1.11); glutathione reductase (GR, EC 1.6.4.2) and peroxidases (POD, EC 1.11.1.7) were determined. In leaves, growth was more depressed by 25 mM Na(2)SO(4) than 50 mM NaCl. The higher sensitivity of basil to Na(2)SO(4) was associated with an enhanced accumulation of H(2)O(2), an inhibition of APX, GR and POD activities (with the exception of POD under the 30-day-treatment) and a lower regeneration of reduced ascorbate (AsA) and reduced glutathione (GSH). However, the changes in the antioxidant metabolism were enough to limit oxidative damage, explaining the fact that RLR and TBARS levels were unchanged under both Na(2)SO(4) and NaCl treatment. Moreover, for both salts the 30-day-treatment reduced H(2)O(2) accumulation, unchanged RLR and TBARS levels, and enhanced the levels of antioxidants and antioxidative enzymes, thus achieving an adaptation mechanism against reactive oxygen species. 2010 Elsevier Masson SAS. All rights reserved.

Evaluation of Antioxidant Compounds and Total Sugar Content in a Nectarine [Prunus persica (L.) Batsch] Progeny

PubMed Central

Abidi, Walid; Jiménez, Sergio; Moreno, María Ángeles; Gogorcena, Yolanda

2011-01-01

Epidemiological studies suggest that consumption of fruit rich in phenolic compounds is associated with health-protective effects due to their antioxidant properties. For these reasons quality evaluation has become an important issue in fruit industry and in breeding programs. Phytochemical traits such as total phenolics, flavonoids, anthocyanins, L-ascorbic acid, sugar content and relative antioxidant capacity (RAC) were analyzed over four years in flesh fruit of an F1 population “Venus” × “Big Top” nectarines. Other traits such as harvesting date, yield, fruit weight, firmness, soluble solids concentration (SSC), pH, titratable acidity (TA) and ripening index (RI) were also determined in the progeny. Results showed high variability among genotypes for all analyzed traits. Total phenolics and flavonoids showed significant positive correlations with RAC implying that both are important antioxidant bioactive compounds in peaches. We found genotypes with enhanced antioxidant capacity and a better performance than progenitors, and in consequence the best marketability. PMID:22072927

In vitro evaluation of antioxidant activity of Cordia dichotoma (Forst f.) bark

PubMed Central

Nariya, Pankaj B.; Bhalodia, Nayan R.; Shukla, Vinay J.; Acharya, Rabinarayan; Nariya, Mukesh B.

2013-01-01

Cordia dichotoma Forst. f. bark, identified as botanical source of Shleshmataka in Ayurvedic pharmacopoeia. Present investigation was undertaken to evaluate possible antioxidant potential of methanolic and butanol extract of C. dichotoma bark. In vitro antioxidant activity of methanolic and butanol extract was determined by 1,1, diphenyl–2, picrylhydrazyl (DPPH) free radical scavenging assay. The extracts were also evaluated for their phenolic contents and antioxidant activity. Phenolic content was measured using Folin–Ciocalteu reagent and was calculated as Gallic acid equivalents. Antiradical activity of methanolic extract was measured by DPPH assay and was compared to ascorbic acid and ferric reducing power of the extract was evaluated by Oyaizu method. In the present study three in vitro models were used to evaluate antioxidant activity. The first two methods were for direct measurement of radical scavenging activity and remaining one method evaluated the reducing power. The present study revealed that the C. dichotoma bark has significant radical scavenging activity. PMID:24049418

In vitro evaluation of antioxidant activity of Cordia dichotoma (Forst f.) bark.

PubMed

Nariya, Pankaj B; Bhalodia, Nayan R; Shukla, Vinay J; Acharya, Rabinarayan; Nariya, Mukesh B

2013-01-01

Cordia dichotoma Forst. f. bark, identified as botanical source of Shleshmataka in Ayurvedic pharmacopoeia. Present investigation was undertaken to evaluate possible antioxidant potential of methanolic and butanol extract of C. dichotoma bark. In vitro antioxidant activity of methanolic and butanol extract was determined by 1,1, diphenyl-2, picrylhydrazyl (DPPH) free radical scavenging assay. The extracts were also evaluated for their phenolic contents and antioxidant activity. Phenolic content was measured using Folin-Ciocalteu reagent and was calculated as Gallic acid equivalents. Antiradical activity of methanolic extract was measured by DPPH assay and was compared to ascorbic acid and ferric reducing power of the extract was evaluated by Oyaizu method. In the present study three in vitro models were used to evaluate antioxidant activity. The first two methods were for direct measurement of radical scavenging activity and remaining one method evaluated the reducing power. The present study revealed that the C. dichotoma bark has significant radical scavenging activity.

Effects of Acifluorfen on Endogenous Antioxidants and Protective Enzymes in Cucumber (Cucumis sativus L.) Cotyledons

PubMed Central

Kenyon, William H.; Duke, Stephen O.

1985-01-01

The herbicide acifluorfen (2-chloro-4-(trifluoromethyl)phenoxy-2-nitrobenzoate) causes strong photooxidative destruction of pigments and lipids in sensitive plant species. Antioxidants and oxygen radical scavengers slow the bleaching action of the herbicide. The effect of acifluorfen on glutathione and ascorbate levels in cucumber (Cucumis sativus L.) cotyledon discs was investigated to assess the relationship between herbicide activity and endogenous antioxidants. Acifluorfen decreased the levels of glutathione and ascorbate over 50% in discs exposed to less than 1.5 hours of white light (450 microeinsteins per square meter per second). Coincident increases in dehydroascorbate and glutathione disulfide were not observed. Acifluorfen also caused the rapid depletion of ascorbate in far-red light grown plants which were photosynthetically incompetent. Glutathione reductase, dehydroascorbate reductase, superoxide dismutase, ascorbate oxidase, ascorbate free radical reductase, peroxidase, and catalase activities rapidly decreased in acifluorfen-treated tissue exposed to white light. None of the enzymes were inhibited in vitro by the herbicide. Acifluorfen causes irreversible photooxidative destruction of plant tissue, in part, by depleting endogenous antioxidants and inhibiting the activities of protective enzymes. PMID:16664506

Effects of administration of beta-carotene, ascorbic acid, persimmons, and pods on antioxidative ability in UV-irradiated ODS rats.

PubMed

Hosotani, Keisuke; Yoshida, Minoru; Kitagawa, Masahiro

2005-07-01

To evaluate the effects of supplementing diets with carotenoid and ascorbic acid (AsA) on the antioxidative ability of Osteogenic Disorder-Shionogi (ODS) rats, we added synthetic beta-carotene (betaC), AsA, and powders of persimmon (Ka) and pods (Po) containing betaC and AsA to the diet and obtained the following results. The urinary 8-hydroxydeoxyguanosine (8-OHdG) concentration was low in the -betaC.AsA and +AsA groups but high in the +betaC.AsA, +Ka, and +Po groups. The thiobarbituric acid-reactive substances (TBARS) in both the liver and skin were higher in the -betaC.AsA group than in the +betaC.AsA group and were low in the +Ka and +Po groups. As antioxidant enzymes, glutathione peroxidase (GSH-Px) activity was high in the +betaC.AsA group, low in the -beta3C.AsA group in both the skin and liver, and also high in the + Ka and +Po group in the liver. Superoxide dismutase (SOD) activity was high in the -betaC.AsA group and low in the +betaC.AsA and +Ka groups in both the skin and liver. Catalase (CAT) activity in the liver was low in the -betaC.AsA, +AsA, and +betaC groups and high in the +betaC.AsA and +Po groups. These results confirmed that the administration of betaC, AsA, and persimmons and pods increases antioxidative ability in the skin and liver of ultraviolet-b(UV-B)-irradiated ODS rats.

Evaluation of physicochemical and antioxidant properties of two stingless bee honeys: a comparison with Apis mellifera honey from Nsukka, Nigeria.

PubMed

Nweze, Justus Amuche; Okafor, J I; Nweze, Emeka I; Nweze, Julius Eyiuche

2017-11-06

Several physical, biochemical and antioxidant properties of two Nigerian stingless bee honey varieties (Melipona sp. and Hypotrigona sp.) were compared with Apis mellifera honey using standard analytical procedures. The mean pH of Apis mellifera, Hypotrigona sp. and Melipona sp. honeys were 4.24 ± 0.28, 3.75 ± 0.11 and 4.21 ± 0.37 respectively. The mean moisture contents of the honeys were 11.74 ± 0.47, 17.50 ± 0.80, and 13.86 ± 1.06%. Honey samples from Hypotrigona sp. when compared with other honey samples had the highest mean total dissolved solids (370.01 ± 22.51 ppm), hydroxymethylfurfural (16.58 ± 0.37 mg/kg), total acidity (35.57 ± 0.42 meq/kg), protein content (16.58 ± 0.37 g/kg), phenol content (527.41 ± 3.60 mg/kg), and ascorbic acid (161.69 ± 6.70 mg/kg), antioxidant equivalent-ascorbic acid assay value (342.33 ± 0.78 mg/kg) as well as ferric reducing power (666.88 ± 1.73 μM Fe(II)/100 g) (p < 0.05). Several strong correlations were observed among some of the parameters of the honeys. This is the first study to compare the properties of Nigerian honey bees. Our results suggested that these honeys (specifically Hypotrigona sp. honey) is a good source of antioxidants comparable to A. mellifera honey.

Screening of various botanical extracts for antioxidant activity using DPPH free radical method.

PubMed

Waqas, Muhammad Khurram; Saqib, Najam-Us; Rashid, Saeed-Ur; Shah, Pervaiz Akhtar; Akhtar, Naveed; Murtaza, Ghulam

2013-01-01

Aiming at the exploration of herbal use by society, crude extracts of the seeds of some commonly used medicinal plants (Vitis vinifera, Tamarindus indica and Glycin max) were screened for their free radical scavenging properties using ascorbic acid as standard antioxidant. Free radical scavenging activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. The overall antioxidant activity of grape seeds (Vitis vinifera) was the strongest, followed in descending order by soybean (Glycin max) and tamarind (Tamarindus indica). The seeds extract of Vitis vinifera, Glycin max and Tamarindus indica showed 85.61%, 83.45% and 79.26%, DPPH scavenging activity respectively.

Rate of antioxidant degradation and color variations in dehydrated apples as related to water activity.

PubMed

Lavelli, Vera; Vantaggi, Claudia

2009-06-10

Dehydrated apples were studied to evaluate the effects of water activity on the stability of their antioxidants and color. Apples were freeze-dried, ground, then equilibrated, and stored at eight water activity levels, ranging from 0.058 to 0.747, at 40 degrees C. Their contents of hydroxycinnamic acids, dihydrochalcones, catechin, epicatechin, polymeric flavan-3-ols, and hydroxymethylfurfural, their antioxidant activity values, and their Hunter colorimetric parameters were analyzed at different storage times. Antioxidant degradation followed pseudo-first-order kinetics and was accelerated by increasing the water activity. The order of antioxidant stability in the products at water activity levels below 0.316 was catechin, epicatechin, and ascorbic acid < total procyanidins < dihydrochalcones and p-coumaric acid < chlorogenic acid; however, in the products at water activity levels above 0.316, the degradation of all antioxidants was very fast. The hydroxymethylfurfural formation rate increased exponentially during storage, especially at high water activity levels. The antioxidant activity of the dehydrated apples decreased during storage, consistent with antioxidant loss. The variations of the colorimetric parameters, namely, lightness (L*), redness (a*), and yellowness (b*), followed pseudo-zero-order kinetics and were accelerated by increasing water activity. All analytical indices indicated that the dehydrated apples were stable at water activity levels below 0.316, with the degradation rate accelerating upon exposure to higher relative humidities. Above 0.316, a small increase in water activity of the product would sharply increase the degradation rate constants for both antioxidant and color variations.

The osmotic/calcium stress theory of brain damage: are free radicals involved?

PubMed

Pazdernik, T L; Layton, M; Nelson, S R; Samson, F E

1992-01-01

This overview presents data showing that glucose use increases and that excitatory amino acids (i.e., glutamate, aspartate), taurine and ascorbate increase in the extracellular fluid during seizures. During the cellular hyperactive state taurine appears to serve as an osmoregulator and ascorbate may serve as either an antioxidant or as a pro-oxidant. Finally, a unifying hypothesis is given for seizure-induced brain damage. This unifying hypothesis states that during seizures there is a release of excitatory amino acids which act on glutamatergic receptors, increasing neuronal activity and thereby increasing glucose use. This hyperactivity of cells causes an influx of calcium (i.e., calcium stress) and water movements (i.e., osmotic stress) into the cells that culminate in brain damage mediated by reactive oxygen species.

Effects of short-term anoxia treatment on browning of fresh-cut Chinese water chestnut in relation to antioxidant activity.

PubMed

You, Yanli; Jiang, Yueming; Sun, Jian; Liu, Hai; Song, Lili; Duan, Xuewu

2012-06-01

The effects of short-term anoxia pre-treatment on browning of fresh-cut Chinese water chestnut (CWC), stored at 4°C, in relation to antioxidant activity were investigated. CWC slices were exposed to pure N 2 for 4h and then stored at 4°C for 18d. Anoxia significantly inhibited browning of CWC slices during storage, accompanied by lower contents of malondialdehyde, H 2 O 2 , and lipoxygenase activity. Furthermore, anoxia induced the activities of superoxide dismutase and ascorbate peroxidase, which could benefit scavenging reactive oxygen species and alleviating lipid peroxidation. In addition, better maintenance of reducing power and free-radical-scavenging activities against α,α-diphenyl-β-picrylhydrazy (DPPH), superoxide anions and hydroxyl was observed in N 2 -treated CWC slices, with higher phenolic compounds and ascorbic acid contents. Collectively, these finds suggest that N 2 pre-treatment enhanced enzymatic and non-enzymatic antioxidant activity in CWC slices, and thereby contributed to alleviating lipid peroxidation and maintenance of storage quality. Copyright © 2011 Elsevier Ltd. All rights reserved.

Interaction of dietary antioxidants in vivo: how fruit and vegetables prevent disease?

PubMed

Eastwood, M A

1999-09-01

Epidemiological studies indicate that fruit and vegetables are health-promoting and protective against disease, particularly cardiovascular disease and cancer. Possible plant nutrients providing this protection include antioxidants and dietary fibre. Clinical trials with antioxidant supplements give inconsistent results for protection against lung cancer in smokers, invasive cervical cancer, oesophageal and gastric cancers, colorectal polyps and coronary heart disease. The antioxidants used in trials may be contributing to a more complex system. Antioxidants have differing solubilities which partition across the phases of tissues, cells and macromolecular structures: water-soluble ascorbate, glutathione and urate; lipid-soluble tocopherols and carotenoids, and intermediatory-soluble flavonoids and hydroxycinnamic acids. The health protection provided by fruit and vegetables could arise through an integrated reductive environment delivered by plant antioxidants of differing solubility in each of the tissue, cellular and macromolecular phases.

BIOCHEMICAL IMPLICATIONS OF PRO-OXIDANTS AND ANTIOXIDANTS

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

Bernheim, F.

1963-01-01

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

Reexamination of the ORAC assay: effect of metal ions.

PubMed

Nkhili, E; Brat, P

2011-05-01

The oxygen radical absorbance capacity (ORAC) assay method has been employed extensively in the field of antioxidant and oxidative stress. It uses fluorescein as probe for oxidation by peroxyl radical. Hundreds of reports have been published on the use of this method to determine antioxidant capacity in food and biological samples. The question is whether the results of all these reports are influenced by antioxidant autoxidation, which occurs during the ORAC test. Indeed, the presence of metal ions in the studied matrix will influence antioxidant stability, thereby leading to the underestimation of their antioxidant properties. Ethylenediaminetetraacetic acid hydrate (EDTA) can be used as a metal complexation agent. This paper examines the effect of the addition of EDTA on the ORAC values of pure compounds (quercetin, ascorbic, and dehydroascorbic acid) and five food juices (kiwi, orange, tomato, red grape, and apple). Metal complexation by EDTA (80 μM) clearly increased the ORAC values, given that the antioxidant was protected against rapid autoxidation incited by trace metal ions within samples and then by free radicals. Our finding also undoubtedly demonstrated that the number of literature values is potentially underestimated.

Antioxidant properties of methanol extract and its solvent fractions obtained from selected Indian red seaweeds.

PubMed

Ganesan, P; Kumar, Chandini S; Bhaskar, N

2008-05-01

In vitro antioxidant activities of three selected Indian red seaweeds - viz., Euchema kappaphycus, Gracilaria edulis and Acanthophora spicifera were evaluated. Total phenolic content and reducing power of crude methanol extract were determined. The antioxidant activities of total methanol extract and five different solvent fractions (viz., petroleum ether (PE), ethyl acetate (EA), dichloromethane (DCM), butanol (BuOH) and aqueous) were also evaluated. EA fraction of A. spicifera exhibited higher total antioxidant activity (32.01 mg ascorbic acid equivalent/g extract) among all the fractions. Higher phenolic content (16.26 mg gallic acid equivalent/g extract) was noticed in PE fraction of G. edulis. Reducing power of crude methanol extract increased with increasing concentration of the extract. Reducing power and hydroxyl radical scavenging activity of E. kappaphycus were higher compared to standard antioxidant (alpha-tocopherol). The total phenol content of all the seaweeds was significantly different (P<0.05). In vitro antioxidant activities of methanol extracts of all the three seaweeds exhibited dose dependency; and increased with increasing concentration of the extract.

Lipolysis and lipid oxidation in fermented sausages depending on different processing conditions and different antioxidants.

PubMed

Zanardi, Emanuela; Ghidini, Sergio; Battaglia, Alessandra; Chizzolini, Roberto

2004-02-01

Lipolysis and lipid oxidation in Mediterranean and North Europe type sausages were studied in relation to raw material, processing conditions and additives. In particular the effect of ascorbic acid, nitrites and spices was evaluated. Lipolysis was measured by the determination of total and free fatty acids of fresh minces and matured products and lipid oxidation was evaluated by thiobarbituric acid reactive substances and cholesterol oxidation products. The increase of free fatty acids during maturation appears to be independent from processing conditions and the differences in polyunsaturated fatty acids increment found among the formulations appear to be due to inherent variations of raw materials. The presence of ascorbic acid and/or nitrite seems important for cholesterol protection and, as a consequence, for the safety of fermented meat products while spices at doses up to 0.1% do not seem to have a remarkable effect. The effect on fatty acid oxidation of the same additives and of the different processing technologies is not significantly different and the variations linked to raw material may play the greatest role.

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

PubMed

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

2017-09-01

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

In Vitro Antioxidant-Activity Evaluation of Gallic-Acid-Grafted Chitosan Conjugate Synthesized by Free-Radical-Induced Grafting Method.

PubMed

Hu, Qiaobin; Wang, Taoran; Zhou, Mingyong; Xue, Jingyi; Luo, Yangchao

2016-07-27

The major objective of this work was to develop a green and facile process to prepare gallic acid-chitosan conjugate and comprehensively evaluate the physicochemical properties and biological activities of an as-prepared water-soluble chitosan derivative. A free-radical-induced grafting approach using an ascorbic acid-hydrogen peroxide redox pair was adopted. The obtained conjugate was characterized by Fourier transform infrared spectroscopy, UV-vis, X-ray diffraction, and pKa analysis. The antioxidant activities were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6)-sulphonic acid (ABTS), reducing power, and oxygen-radical antioxidant-capacity assays. The results showed that the mass ratio of gallic acid to chitosan played a vital role in determining the grafting degree and ζ potential of the conjugates, with the ratio of 0.5:1 being the optimal ratio that resulted in the highest grafting degree. The antioxidant assays demonstrated that conjugation significantly improved the antioxidant activities, being dramatically higher than that of free chitosan. It was notable that the DPPH- and ABTS-scavenging activities of conjugate at 0.4 mg/mL reached the same level as the free gallic acid at the equivalent concentration. Our study demonstrated a green and facile synthesis approach to preparing a novel water-soluble chitosan derivative that may have promising potentials in the food industry.

The high affinity of small-molecule antioxidants for hemoglobin.

PubMed

Puscas, Cristina; Radu, Luana; Carrascoza, Francisco; Mot, Augustin C; Amariei, Diana; Lungu, Oana; Scurtu, Florina; Podea, Paula; Septelean, Raluca; Matei, Alina; Mic, Mihaela; Attia, Amr A; Silaghi-Dumitrescu, Radu

2018-06-18

Hemoglobin has previously been shown to display ascorbate peroxidase and urate peroxidase activity, with measurable Michaelis-Menten parameters that reveal a particularly low Km for ascorbate as well as for urate - lower than the respective in vivo concentrations of these antioxidants in blood. Also, direct detection of a hemoglobin-ascorbate interaction was possible by monitoring the 1H-NMR spectrum of ascorbate in the presence of hemoglobin. The relative difference in structures between ascorbate and urate may raise the question as to exactly what the defining structural features would be, for a substrate that binds to hemoglobin with high affinity. Reported here are Michaelis-Menten parameters for hemoglobin acting as peroxidase against a number of other substrates of varying structures - gallate, caffeate, rutin, 3-hydroxyflavone, 3,6-dihydroxyflavone, quercetin, epicatechin, luteolin - all with high affinities (some higher than those of physiologically-relevant redox partners of Hb - ascorbate and urate). Moreover, this high affinity appears general to animal hemoglobins. 1 H-NMR and 13 C-NMR spectra reveal a general pattern wherein small hydrophilic antioxidants appear to all have their signals affected, presumably due to binding to hemoglobin. Fluorescence and calorimetry measurements confirm these conclusions. Docking calculations confirm the existence of binding sites on hemoglobin and on myoglobin for ascorbate as well as for other antioxidants. Support is found for involvement of Tyr42 in binding of three out of the four substrates investigated in the case of hemoglobin (including ascorbate and urate, as blood-contained relevant substrates), but also for Tyr145 (with urate and caffeate) and Tyr35 (with gallate). Copyright © 2018 Elsevier Inc. All rights reserved.

Galactose alters markers of oxidative stress and acetylcholinesterase activity in the cerebrum of rats: protective role of antioxidants.

PubMed

Delwing-de Lima, Daniela; Fröhlich, Monique; Dalmedico, Leticia; Aurélio, Juliana Gruenwaldt Maia; Delwing-Dal Magro, Débora; Pereira, Eduardo Manoel; Wyse, Angela T S

2017-04-01

We evaluated the in vitro effects of galactose at 0.1, 3.0, 5.0 and 10.0 mM on thiobarbituric acid-reactive substances (TBA-RS), total sulfhydryl content, protein carbonyl content, on the activities of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and on acetylcholinesterase (AChE) activity in the cerebral cortex, cerebellum and hippocampus of rats. We also investigated the influence of the antioxidants (each at 1 mM), α-tocopherol, ascorbic acid and glutathione, on the effects elicited by galactose on the parameters tested. Results showed that galactose, at a concentration of 3.0 mM, enhanced TBA-RS levels in the hippocampus, cerebral cortex and cerebellum of rats. In the cerebral cortex, galactose at concentrations of 5.0 and 10.0 mM increased TBA-RS and protein carbonyl content, and at 10.0 mM increased CAT activity and decreased AChE activity. In the cerebellum, galactose at concentrations of 5.0 and 10.0 mM increased TBA-RS, SOD and GSH-Px activities. In the hippocampus, galactose at concentrations of 5.0 and 10.0 mM increased TBA-RS and CAT activity and at 10.0 mM decreased GSH-Px. Data showed that at the pathologically high concentration (greater than 5.0 mM), galactose induces lipid peroxidation, protein carbonylation, alters antioxidant defenses in the cerebrum, and also alters cholinesterase activity. Trolox, ascorbic acid and glutathione addition prevented the majority of alterations in oxidative stress parameters and the decrease in AChE activity that were caused by galactose. Our findings lend support to a potential therapeutic strategy for this condition, which may include the use of appropriate antioxidants for ameliorating the damage caused by galactose.

Determination of total antioxidant capacity by a new spectrophotometric method based on Ce(IV) reducing capacity measurement.

PubMed

Ozyurt, Dilek; Demirata, Birsen; Apak, Resat

2007-02-28

Dietary antioxidants widely found in fruits and vegetables may serve the task of reducing oxidative damage in humans induced by free radicals and reactive oxygen species under 'oxidative stress' conditions. The aim of this work is to develop a simple, low-cost, sensitive, and diversely applicable indirect spectrophotometric method for the determination of total antioxidant capacity of several plants. The method is based on the oxidation of antioxidants with cerium(IV) sulfate in dilute sulfuric acid at room temperature. The Ce(IV) reducing capacity of the sample is measured under carefully adjusted conditions of oxidant concentration and pH such that only antioxidants and not other organic compounds would be oxidized. The spectrophotometric determination of the remaining Ce(IV) was performed after completion of reaction with antioxidants. Quercetin and gallic acid were used as standards for flavonoids and phenolic acids, respectively, and results of antioxidant measurements were reported as trolox equivalents. The developed procedure was successfully applied to the assay of total antioxidant capacity due to simple compounds such as trolox, quercetin, gallic acid, ascorbic acid, catechin, naringin, naringenin, caffeic acid, chlorogenic acid, ferulic acid, and p-coumaric acid, and due to phenolic acids and flavonoids in the arieal parts of nettle (Urtica Dioica L.). Blank correction of significantly absorbing plant extracts at 320nm could be made with the aid of spectrophotometric titration. Plant selection was made in respect to high antioxidant content, and extraction was made with water. The proposed method was reproducible, and the trolox equivalent antioxidant capacities (TEAC coefficients) of the tested antioxidant compounds were correlated to those found by reference methods such as ABTS and CUPRAC. Since the TEAC coefficients found with the proposed method of naringin-naringenin and rutin-catechin pairs were close to each other, this Ce(IV)-based assay probably caused the simultaneous hydrolysis of flavonoid glycosides to the corresponding aglycones and their subsequent oxidation such that the hydrolysis products exhibed antioxidant capacities roughly proportional the number of -OH groups contained in a molecule.

Antimutagenic and antioxidant properties of the aqueous extracts of organic and conventional grapevine Vitis labrusca cv. Isabella leaves in V79 cells.

PubMed

Trindade, Cristiano; Bortolini, Giovana Vera; Costa, Bárbara Segalotto; Anghinoni, Joanna Carra; Guecheva, Temenouga Nikolova; Arias, Ximena; Césio, Maria Verónica; Heinzen, Horácio; Moura, Dinara Jaqueline; Saffi, Jenifer; Salvador, Mirian; Henriques, João Antonio Pêgas

2016-01-01

Grapes are one of the most commonly consumed fruit, in both fresh and processed forms; however, a significant amount is disposed of in the environment. Searching for a use of this waste, the antigenotoxic, antimutagenic, and antioxidant activities of aqueous extracts from organic and conventional Vitis labrusca leaves were determined using V79 cells as model. The antigenotoxic activity was analyzed by the alkaline comet assay using endonuclease III and formamidopyrimidine DNA glycosylase enzymes. The antimutagenic property was assessed through the micronucleus (MN) formation, and antioxidant activities were assessed using 2',7'-dichlorodihydrofluorescin diacetate (DCFH-DA) assay and 2,2-diphenyl-1-picrylhydrazyl (DPPH(●)) radical scavenging, as well as with superoxide dismutase (SOD) and catalase (CAT) activity assays. In addition, phenolic content and ascorbic acid levels of both extracts were determined. Data showed that both organic and conventional grapevine leaves extracts possessed antigenotoxic and antimutagenic properties. The extract of organic leaves significantly reduced intracellular reactive oxygen species (ROS) levels in V79 cells, and displayed greater ability for DPPH(●) scavenging and higher SOD and CAT activities than extract from conventional leaves. Further, the extract from organic leaves contained higher phenolic and ascorbic acid concentrations. In summary, extracts from organic and conventional grape leaves induced important in vitro biological effects.

Antioxidant and anti-inflammatory activities of silver nanoparticles biosynthesized from aqueous leaves extracts of four Terminalia species

NASA Astrophysics Data System (ADS)

El-Rafie, Hanaa Mohamed; Abdel-Aziz Hamed, Manal

2014-09-01

The environmentally friendly synthesis of nanoparticles process is a revolutionary step in the field of nanotechnology. In recent years plant mediated biological synthesis of nanoparticles has been gaining importance due to its simplicity and eco-friendliness. In this study, a simple and an efficient eco-friendly approach for the biosynthesis of stable, monodisperse silver nanoparticles using aqueous extracts of four Terminalia species, namely, Terminalia catappa, Terminalia mellueri, Terminalia bentazoe and Terminalia bellerica were described. The silver nanoparticles were characterized in terms of synthesis, capping functionalities (polysaccharides, phenolics and flavonoidal compounds) and microscopic evaluation by UV-visible spectroscopy, Fourier transform infrared spectroscopy and transmission electron microscopy. The results showed a simple and feasible approach for obtaining stable aqueous monodispersive silver nanoparticles. Furthermore, biological activity of the biosynthesized silver nanoparticles was examined. Concerning this, dose-dependent antioxidant activity of silver nanoparticles imparted by the plant phenolic and flavonoidal components was evaluated using in vitro 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and found to be comparable to standard ascorbic acid. The same holds true for the anti-inflammatory activity where Terminalia catappa and Terminalia mellueri have a high-test inhibition percentage better than that of ascorbic acid in the carrageenan induced hind paw edema. The results also revealed that the aqueous extract of Terminallia catapa and its silver nanoparticles recorded the most potent in vivo antioxidant effect.

Hydrogen Sulfide Alleviates Postharvest Senescence of Grape by Modulating the Antioxidant Defenses

PubMed Central

Ni, Zhi-Jing; Hu, Kang-Di; Song, Chang-Bing; Ma, Run-Hui; Li, Zhi-Rong; Zheng, Ji-Lian; Fu, Liu-Hui

2016-01-01

Hydrogen sulfide (H2S) has been identified as an important gaseous signal in plants. Here, we investigated the mechanism of H2S in alleviating postharvest senescence and rotting of Kyoho grape. Exogenous application of H2S released from 1.0 mM NaHS remarkably decreased the rotting and threshing rate of grape berries. H2S application also prevented the weight loss in grape clusters and inhibited the decreases in firmness, soluble solids, and titratable acidity in grape pulp during postharvest storage. The data of chlorophyll and carotenoid content suggested the role of H2S in preventing chlorophyll breakdown and carotenoid accumulation in both grape rachis and pulp. In comparison to water control, exogenous H2S application maintained significantly higher levels of ascorbic acid and flavonoid and total phenolics and reducing sugar and soluble protein in grape pulp. Meanwhile, H2S significantly reduced the accumulation of malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide anion (O2 ∙−) in grape pulp. Further investigations showed that H2S enhanced the activities of antioxidant enzymes ascorbate peroxidase (APX) and catalase (CAT) and decreased those of lipoxygenase (LOX) in both grape peels and pulp. In all, we provided strong evidence that H2S effectively alleviated postharvest senescence and rotting of Kyoho grape by modulating antioxidant enzymes and attenuating lipid peroxidation. PMID:27594971

Characterization analysis for leaves of Leucaena leucocephala by using phytochemical screening assay

NASA Astrophysics Data System (ADS)

Zarina, Z.; Ghazali, C. M. R.; Sam, S. T.

2017-09-01

Leucaena Leucocephala (Lam.) de Wit (Petai Belalang) is a medium plant which belong in group of tropical breed that can survived in hot, dried and warm environment. In Malaysia, the plant is available abundantly. As there are still no commercial used, and no serious intention in finding the benefits of L. Leucocephala, this work come out with the idea to analyze the antioxidants contains in leaves of the plant by undergoes different extraction and chemical testing method. The phytochemical screening assay involved in this study are antioxidant activity by using free radical diphenylpicrylhydrazyl (DPPH) method, total phenolic content by using Folin-Ciocalteu method, total flavonoid content by using colorimetric assay with ascorbic acid and quercetin were used as reference standards while for phosphorus analysis, a molybdenum blue method or also known as ascorbic acid method was used. For antioxidant activity by using free radical diphenylpicrylhydrazyl (DPPH) method, higher concentration was recorded by extraction using methanol (dried sample) which is 8247.0 mg/L, for total phenolic content higher concentration was recorded by extraction using deionized water (dried sample) which is 4276.0 mg/L, for total flavonoid content by using colorimetric assay higher concentration was recorded by extraction using methanol (dried sample) which is 4439.0 mg/L, and for for phosphorus analysis higher concentration was recorded by extraction using methanol (dried sample) which is 71.057 mg/L.

Characterization analysis for leaves of Leucaena Leucocephala by using phytochemical screening assay

NASA Astrophysics Data System (ADS)

Zarina, Z.; Ghazali, C. M. R.; Sam, S. T.

2017-09-01

Leucaena Leucocephala (Lam.) de Wit (Petai Belalang) is a medium plant which belong in group of tropical breed that can survived in hot, dried and warm environment. In Malaysia, the plant is available abundantly. As there are still no commercial used, and no serious intention in finding the benefits of L. Leucocephala, this work come out with the idea to analyze the antioxidants contains in leaves of the plant by undergoes different extraction and chemical testing method. The phytochemical screening assay involved in this study are antioxidant activity by using free radical diphenylpicrylhydrazyl (DPPH) method, total phenolic content by using Folin-Ciocalteu method, total flavonoid content by using colorimetric assay with ascorbic acid and quercetin were used as reference standards while for phosphorus analysis, a molybdenum blue method or also known as ascorbic acid method was used. For antioxidant activity by using free radical diphenylpicrylhydrazyl (DPPH) method, higher concentration was recorded by extraction using methanol (dried sample) which is 8247.0 mg/L, for total phenolic content higher concentration was recorded by extraction using deionized water (dried sample) which is 4276.0 mg/L, for total flavonoid content by using colorimetric assay higher concentration was recorded by extraction using methanol (dried sample) which is 4439.0 mg/L, and for for phosphorus analysis higher concentration was recorded by extraction using methanol (dried sample) which is 71.057 mg/L.

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

PubMed

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

2014-12-01

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

Oral administration of L-arginine in patients with angina or following myocardial infarction may be protective by increasing plasma superoxide dismutase and total thiols with reduction in serum cholesterol and xanthine oxidase

PubMed Central

Tripathi, Pratima; Chandra, M

2009-01-01

Administration of L-arginine has been shown to control ischemic injury by producing nitric oxide which dilates the vessels and thus maintains proper blood flow to the myocardium. In the present study attempt has been made to determine whether oral administration of L-arginine has any effect on oxidant/antioxidant homeostasis in ischemic myocardial patients [represented by the patients of acute angina (AA) and acute myocardial infarction (MI)]. L-arginine has antioxidant and antiapoptotic properties, decreases endothelin-1 expression and improves endothelial function, thereby controlling oxidative injury caused during myocardial ischemic syndrome. Effect of L-arginine administration on the status of free radical scavenging enzymes, pro-oxidant enzyme and antioxidants viz. total thiols, carbonyl content and plasma ascorbic acid levels in the patients has been evaluated. We have observed that L-arginine administration (three grams per day for 15 days) resulted in increased activity of free radical scavenging enzyme superoxide dismutase (SOD) and increase in the levels of total thiols (T-SH) and ascorbic acid with concomitant decrease in lipid per-oxidation, carbonyl content, serum cholesterol and the activity of proxidant enzyme, xanthine oxidase (XO). These findings suggest that the supplementation of L-arginine along with regular therapy may be beneficial to the patients of ischemic myocardial syndromes. PMID:20716909

Proximate Composition and Antioxidant Potential of Leaves from Three Varieties of Mulberry (Morus sp.): A Comparative Study

PubMed Central

Iqbal, Shahid; Younas, Umer; Sirajuddin; Chan, Kim Wei; Sarfraz, Raja Adil; Uddin, Kamal

2012-01-01

In this study, leaves of three indigenous varieties of Mulberry namely, Morus alba L., Morus nigra L. and Morus rubra L. were investigated for their antioxidant potential and their proximate composition was determined. The yields of 80% methanolic extracts ranged between 8.28–13.89%. The contents of total phenolics (TPC), total flavonoids (TFC) and ascorbic acid (AA) ranged between 16.21–24.37 mg gallic acid equivalent (GAE)/g, 26.41–31.28 mg rutin equivalent (RE)/g and 0.97–1.49 mg/g, respectively. The antioxidant activity of leaf extracts was evaluated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH•) radical scavenging actity, 2,2′-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid (ABTS•+) radical cation scavenging capacity and ferric ion reducing power and values ranged between 1.89–2.12, 6.12–9.89 and 0.56–0.97 mM Trolox equivalent/g of dried leaves, respectively. The investigated features reveal good nutritive and antioxidant attributes of all the varieties with mutually significant differences. PMID:22837655

Control of Root Rot and Wilt Diseases of Roselle under Field Conditions

PubMed Central

Hassan, Naglaa; Elsharkawy, Mohsen Mohamed; Shimizu, Masafumi

2014-01-01

Roselle (Hibiscus sabdariffa L.) is one of the most important medicinal crops in many parts of the world. In this study, the effects of microelements, antioxidants, and bioagents on Fusarium oxysporum, F. solani, and Macrophomina phaseolina, the causal pathogens of root rot and wilt diseases in roselle, were examined under field conditions. Preliminary studies were carried out in vitro in order to select the most effective members to be used in field control trials. Our results showed that microelements (copper and manganese), antioxidants (salicylic acid, ascorbic acid, and EDTA), a fungicide (Dithane M45) and biological control agents (Trichoderma harzianum and Bacillus subtilis) were significantly reduced the linear growth of the causal pathogens. Additionally, application of the previous microelements, antioxidants, a fungicide and biological control agents significantly reduced disease incidence of root rot and wilt diseases under field conditions. Copper, salicylic acid, and T. harzianum showed the best results in this respect. In conclusion, microelements, antioxidants, and biocontrol agents could be used as alternative strategies to fungicides for controlling root rot and wilt diseases in roselle. PMID:25606010

Lipoic acid mitigates oxidative stress and recovers metabolic distortions in salt-stressed wheat seedlings by modulating ion homeostasis, the osmo-regulator level and antioxidant system.

PubMed

Gorcek, Zeynep; Erdal, Serkan

2015-11-01

Soil salinity is one of the most detrimental environmental factors affecting the growth of plants and limiting their agricultural productivity. This study investigated whether exogenous lipoic acid (LA) pretreatment plays a role in promoting salt tolerance in wheat seedlings. The seedlings were treated with LA (1.75 mmol L(-1)) and salt (100 mmol L(-1) NaCl) separately and a combination of them. Salt stress significantly reduced relative water content, leaf surface area, ribulose bisphosphate carboxylase expression, and chlorophyll content but increased the content of osmo-regulator protein, carbohydrates and proline. In addition, salinity led to an imbalance in the inorganic composition of wheat leaves. While it elevated Na(+) content compared to control, Ca content and K(+)/Na(+) ratio were reduced. Under saline conditions, despite increases in antioxidant enzyme activity and levels of antioxidant compounds (ascorbate and glutathione), the content of reactive oxygen species (superoxide anion, hydrogen peroxide) and malondialdehyde were higher than in control seedlings. LA significantly promoted osmo-regulator level and antioxidant enzyme activities compared to stressed seedlings alone. Also, it both increased levels of ascorbate and glutathione and regenerated their oxidised forms, thus contributing to maintaining cellular redox status. Similarly, LA prevented excessive accumulation of Na(+) and promoted K(+)/Na(+) ratio and Ca content. Reactive oxygen species content was significantly reduced, and the inhibitions in the above parameters markedly recovered. LA reduced salinity-induced oxidative damage and thus contributed to the growth and development of plants in saline soils by modulating ion homeostasis between plant and soil as well as in osmo-regulator content and antioxidant system. © 2014 Society of Chemical Industry.

Effects of hot air and freeze drying methods on antioxidant activity, colour and some nutritional characteristics of strawberry tree (Arbutus unedo L) fruit.

PubMed

Orak, H H; Aktas, T; Yagar, H; İsbilir, S Selen; Ekinci, N; Sahin, F Hasturk

2012-08-01

Antioxidant activity, colour and some nutritional properties of hot air and freeze-dried strawberry tree (Arbutus unedo L.) fruits were investigated. Additionally, the effects of two pre-treatments, namely ethyl oleate and water blanching, were compared in terms of drying characteristics. For determination of antioxidant activities in ethanol extracts, two different analytical methods were used: 1,1-diphenyl-2-picrylhydrazyl scavenging activity and β-carotene bleaching activity. As a result, the ethyl oleate pre-treatment shortened the drying time by hot air method and gave a higher 1,1-diphenyl-2-picrylhydrazyl scavenging activity (82.16 ± 0.34%), total phenolic content (7.62 ± 1.09 µg GAE/g extract), ascorbic acid content (236.93 ± 20.14 mg/100 g), besides hydromethylfurfural was not observed. Freeze-dried fruits exhibited higher ascorbic acid content (368.63 ± 17.16 mg/100 g) than those fresh fruits (231.33 ± 19.51 mg/100 g) and nearly 1,1-diphenyl-2-picrylhydrazyl activity (93.52 ± 0.41 %) to fresh fruits (94.03 ± 1.18%). Colour characteristics, sugar content and mineral contents of fruits were significantly affected by pre-treatments and drying methods (p < 0.05). It is concluded that the drying of strawberry tree fruits should bring a valuable and attractive foodstuff to food industry due to the rich nutritional components, antioxidant activity and colour. Another conclusion from this study is that the freeze-drying is the best drying method to keep the nutritional value, antioxidant activity and sensory properties of fruits.

Effect of different drying methods on chlorophyll, ascorbic acid and antioxidant compounds retention of leaves of Hibiscus sabdariffa L.

PubMed

Kumar, Sandopu Sravan; Manoj, Prabhakaran; Shetty, Nandini P; Giridhar, Parvatam

2015-07-01

Use of the indigenous, easily accessible leafy vegetable roselle (Hibiscus sabdariffa L.) for value addition is gaining impetus as its nutritive and nutraceutical compounds are exposed by investigations. Being a perishable, storage is challenging, hence different methods of drying have been an attractive alternative for its postharvest usage in foods without much compromising its quality and antioxidant potential. Room- and freeze-dried samples were found to have best quality in terms of colour, total flavonoid content (18.53 ± 2.39 and 18.66 ± 1.06 g kg(-1) respectively), total phenolic content (17.76 ± 1.93 and 18.91 ± 0.48 g kg(-1)), chlorophyll content (1.59 ± 0.001 and 1.55 ± 0.001 g kg(-1)) and ascorbic acid content (11.11 ± 1.04 and 8.92 ± 0.94 g kg(-1)) compared with those subjected to infrared, crossflow, microwave, oven or sun drying. Samples treated by room and freeze drying retained maximum antioxidant potential as shown by the phosphomolybdate method and the 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging activity and ferric-reducing antioxidant power assays. Cold water and hot water extracts showed significantly higher total phenolic content and total antioxidant activity owing to the greater solubility of phenolics and destruction of cellular components in polar solvents than in organic solvents. The data obtained show the potential for retaining quality parameters of roselle leaf under suitable drying methods. © 2014 Society of Chemical Industry.

Perturbations in carotenoid and porphyrin status result in differential photooxidative stress signaling and antioxidant responses.

PubMed

Park, Joon-Heum; Jung, Sunyo

2018-02-12

We examined differential photooxidative stress signaling and antioxidant responses in rice plants treated with norflurazon (NF) and oxyfluorfen (OF), which are inhibitors of carotenoid and porphyrin biosynthesis, respectively. Plants treated with OF markedly increased levels of cellular leakage and malondialdehyde, compared with NF-treated plants, showing that OF plants suffered greater oxidative damage with respect to membrane integrity. The enhanced production of H 2 O 2 in response to OF, but not NF, indicates the important role of H 2 O 2 in activation of photooxidative stress signaling in OF plants. In response to NF and OF, the increased levels of free salicylic acid as well as maintenance of the redox ratio of ascorbate and glutathione pools to a certain level are considered to be crucial factors in the protection against photooxidation. Plants treated with OF greatly up-regulated catalase (CAT) activity and Cat transcript levels, compared with NF-treated plants. Interestingly, NF plants showed no noticeable increase in oxidative metabolism, although they did show considerable increases in ascorbate peroxidase (APX) and peroxidase activities and transcript levels of APX, as in OF plants. Our results suggest that perturbations in carotenoid and porphyrin status by NF and OF can be sensed by differential photooxidative stress signaling, such as that involving H 2 O 2 , redox state of ascorbate and glutathione, and salicylic acid, which may be responsible for at least part of the induction of ROS-scavenging enzymes. Copyright © 2018 Elsevier Inc. All rights reserved.

Alternation of light/dark period priming enhances clomazone tolerance by increasing the levels of ascorbate and phenolic compounds and ROS detoxification in tobacco (Nicotiana tabacum L.) plantlets.

PubMed

Darwish, Majd; Lopez-Lauri, Félicie; Vidal, Véronique; El Maâtaoui, Mohamed; Sallanon, Huguette

2015-07-01

The effect of the alternation of light/dark periods (AL) (16/8 min light/dark cycles and a photosynthetic photon flux density (PPFD) of 50 μmol photons m(-2) s(-1) for three days) to clarify the mechanisms involved in the clomazone tolerance of tobacco plantlets primed with AL was studied. Clomazone decreased PSII activity, the net photosynthetic rate (Pn), and the ascorbate and total polyphenol contents and increased H2O2 and starch grain accumulation and the number of the cells that underwent programmed cell death (PCD). The pretreatment with AL reduced the inhibitory effect of clomazone on the PSII activity and photosynthesis, as indicated by the decreases in the H2O2 and starch grain accumulation and the PCD levels, and increased the content of ascorbate and certain phenolic compounds, such as chlorogenic acid, neochlorogenic acid and rutin. The AL treatment could promote photorespiration via post-illumination burst (PIB) effects. This alternative photorespiratory electron pathway may reduce H2O2 generation via the consumption of photochemical energy, such as NADH+H(+). At 10 days (D10) of AL treatment, this process induced moderate stress which stimulates H2O2 detoxification systems by increasing the activity of antioxidant enzymes and the biosynthesis of antioxidant components. Therefore, the PCD levels provoked by clomazone were noticeably decreased. Copyright © 2015 Elsevier B.V. All rights reserved.

Antioxidants inhibit SAA formation and pro-inflammatory cytokine release in a human cell model of alkaptonuria.

PubMed

Spreafico, Adriano; Millucci, Lia; Ghezzi, Lorenzo; Geminiani, Michela; Braconi, Daniela; Amato, Loredana; Chellini, Federico; Frediani, Bruno; Moretti, Elena; Collodel, Giulia; Bernardini, Giulia; Santucci, Annalisa

2013-09-01

Alkaptonuria (AKU) is an ultra-rare autosomal recessive disease that currently lacks an appropriate therapy. Recently we provided experimental evidence that AKU is a secondary serum amyloid A (SAA)-based amyloidosis. The aim of the present work was to evaluate the use of antioxidants to inhibit SAA amyloid and pro-inflammatory cytokine release in AKU. We adopted a human chondrocytic cell AKU model to evaluate the anti-amyloid capacity of a set of antioxidants that had previously been shown to counteract ochronosis in a serum AKU model. Amyloid presence was evaluated by Congo red staining. Homogentisic acid-induced SAA production and pro-inflammatory cytokine release (overexpressed in AKU patients) were evaluated by ELISA and multiplex systems, respectively. Lipid peroxidation was evaluated by means of a fluorescence-based assay. Our AKU model allowed us to prove the efficacy of ascorbic acid combined with N-acetylcysteine, taurine, phytic acid and lipoic acid in significantly inhibiting SAA production, pro-inflammatory cytokine release and membrane lipid peroxidation. All the tested antioxidant compounds were able to reduce the production of amyloid and may be the basis for establishing new therapies for AKU amyloidosis.

Antioxidants inhibit SAA formation and pro-inflammatory cytokine release in a human cell model of alkaptonuria

PubMed Central

Spreafico, Adriano; Millucci, Lia; Ghezzi, Lorenzo; Geminiani, Michela; Braconi, Daniela; Amato, Loredana; Chellini, Federico; Frediani, Bruno; Moretti, Elena; Collodel, Giulia; Bernardini, Giulia

2013-01-01

Objective. Alkaptonuria (AKU) is an ultra-rare autosomal recessive disease that currently lacks an appropriate therapy. Recently we provided experimental evidence that AKU is a secondary serum amyloid A (SAA)-based amyloidosis. The aim of the present work was to evaluate the use of antioxidants to inhibit SAA amyloid and pro-inflammatory cytokine release in AKU. Methods. We adopted a human chondrocytic cell AKU model to evaluate the anti-amyloid capacity of a set of antioxidants that had previously been shown to counteract ochronosis in a serum AKU model. Amyloid presence was evaluated by Congo red staining. Homogentisic acid-induced SAA production and pro-inflammatory cytokine release (overexpressed in AKU patients) were evaluated by ELISA and multiplex systems, respectively. Lipid peroxidation was evaluated by means of a fluorescence-based assay. Results. Our AKU model allowed us to prove the efficacy of ascorbic acid combined with N-acetylcysteine, taurine, phytic acid and lipoic acid in significantly inhibiting SAA production, pro-inflammatory cytokine release and membrane lipid peroxidation. Conclusion. All the tested antioxidant compounds were able to reduce the production of amyloid and may be the basis for establishing new therapies for AKU amyloidosis. PMID:23704321

Physico-chemical properties, antioxidant activity and mineral contents of pineapple genotypes grown in china.

PubMed

Lu, Xin-Hua; Sun, De-Quan; Wu, Qing-Song; Liu, Sheng-Hui; Sun, Guang-Ming

2014-06-23

The fruit physico-chemical properties, antioxidant activity and mineral contents of 26 pineapple [Ananas comosus (L.) Merr.] genotypes grown in China were measured. The results showed great quantitative differences in the composition of these pineapple genotypes. Sucrose was the dominant sugar in all 26 genotypes, while citric acid was the principal organic acid. Potassium, calcium and magnesium were the major mineral constituents. The ascorbic acid (AsA) content ranged from 5.08 to 33.57 mg/100 g fresh weight (FW), while the total phenolic (TP) content varied from 31.48 to 77.55 mg gallic acid equivalents (GAE)/100 g FW. The two parameters in the predominant cultivars Comte de Paris and Smooth Cayenne were relative low. However, MD-2 indicated the highest AsA and TP contents (33.57 mg/100 g and 77.55 mg GAE/100 g FM, respectively), and it also showed the strongest antioxidant capacity 22.85 and 17.30 μmol TE/g FW using DPPH and TEAC methods, respectively. The antioxidant capacity of pineapple was correlated with the contents of phenolics, flavonoids and AsA. The present study provided important information for the further application of those pineapple genotypes.

Hydroxyl radical scavenging assay of phenolics and flavonoids with a modified cupric reducing antioxidant capacity (CUPRAC) method using catalase for hydrogen peroxide degradation.

PubMed

Ozyürek, Mustafa; Bektaşoğlu, Burcu; Güçlü, Kubilay; Apak, Reşat

2008-06-02

Hydroxyl radicals (OH) generated in the human body may play an important role in tissue injury at sites of inflammation in oxidative stress-originated diseases. As a more convenient, efficient, and less costly alternative to HPLC/electrochemical detection techniques and to the nonspecific, low-yield deoxyribose (TBARS) test, we used a salicylate probe for detecting OH generated by the reaction of iron(II)-EDTA complex with H(2)O(2). The produced hydroxyl radicals attack both the salicylate probe and the hydroxyl radical scavengers that are incubated in solution for 10 min. Added radical scavengers compete with salicylate for the OH produced, and diminish chromophore formation from Cu(II)-neocuproine. At the end of the incubation period, the reaction was stopped by adding catalase. With the aid of this reaction, a kinetic approach was adopted to assess the hydroxyl radical scavenging properties of polyphenolics, flavonoids and other compounds (e.g., ascorbic acid, glucose, mannitol). A second-order rate constant for the reaction of the scavenger with OH could be deduced from the inhibition of colour formation due to the salicylate probe. In addition to phenolics and flavonoids, five kinds of herbs were evaluated for their OH scavenging activity using the developed method. The modified CUPRAC (cupric ion reducing antioxidant capacity) assay proved to be efficient for ascorbic acid, gallic acid and chlorogenic acid, for which the deoxyribose assay test is basically nonresponsive. An important contribution of this developed assay is the inhibition of the Fenton reaction with catalase degradation of hydrogen peroxide so that the remaining H(2)O(2) would neither give a CUPRAC absorbance nor involve in redox cycling of phenolic antioxidants, enabling the rapid assay of polyphenolics.

Stability and anti-glycation properties of intermediate moisture apple products fortified with green tea.

PubMed

Lavelli, Vera; Corey, Mark; Kerr, William; Vantaggi, Claudia

2011-07-15

Intermediate moisture products made from blanched apple flesh and green tea extract (about 6mg of monomeric flavan 3-ols added per g of dry apple) or blanched apple flesh (control) were produced, and their quality attributes were investigated over storage for two months at water activity (a(w)) levels of 0.55 and 0.75, at 30°C. Products were evaluated for colour (L(∗), a(∗), and b(∗) Hunter's parameters), phytochemical contents (flavan 3-ols, chlorogenic acid, dihydrochalcones, ascorbic acid and total polyphenols), ferric reducing antioxidant potential, 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radical-scavenging activity and ability to inhibit formation of fructose-induced advanced glycation end-products. During storage of the fortified and unfortified intermediate moisture apples, water availability was sufficient to support various chemical reactions involving phytochemicals, which degraded at different rates: ascorbic acid>flavan 3-ols>dihydrochalcones and chlorogenic acid. Colour variations occurred at slightly slower rates after green tea addition. In the intermediate moisture apple, antioxidant and anti-glycoxidative properties decreased at similar rates (half-life was about 80d at a(w) of 0.75, 30°C). In the green tea-fortified intermediate moisture apple, the antioxidant activity decreased at a slow rate (half-life was 165d at a(w) of 0.75, 30°C) and the anti-glycoxidative properties did not change, indicating that flavan 3-ol degradation involved the formation of derivatives that retained the properties of their parent compounds. Since these properties are linked to oxidative- and advanced glycation end-product-related diseases, these results suggest that green tea fortification of intermediate moisture apple products could be a valuable means of product innovation, to address consumers' nutritional needs. Copyright © 2011 Elsevier Ltd. All rights reserved.

Flaxseed hull: Chemical composition and antioxidant activity during development.

PubMed

Herchi, Wahid; Al Hujaili, Abdullah D; Sakouhi, Faouzi; Sebei, Khaled; Trabelsi, Hajer; Kallel, Habib; Boukhchina, Sadok

2014-01-01

Changes in the chemical composition and antioxidant activity of flaxseed hull during maturation were investigated. P129 hull variety was studied at four maturation stages (St1, St2, St3, and St4). Significant variation in proximate composition and flaxseed hull oil characteristics were observed. A significant increase in the carbohydrates content of the hull was observed during development. The main methyl esters were linolenic acid (48.95 - 51.52 %), oleic acid (20.27-23.41%) and linoleic acid (15.62-17.70%). The highest polyunsaturated fatty acids (PUFA) were found to be 67.14 % at the first stage of maturity (St1). Flaxseed hull oil was of good quality, containing an abundance of omega-3 essential fatty acids. The iodine value increased, while the saponification value of oil decreased during seed development. The decrease in ascorbic acid content was steady. The maximum level of total phenolic acid content (128.3 mg/100 g oil) was reached at 7 DAF. The antioxidant activity of oilseed was assessed by means of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay. Radical scavenging activity for green hull was 52.74% and mature hull was 69.32%.

Simultaneous induction of sod, glutathione reductase, GSH, and ascorbate in liver and kidney correlates with survival during aging.

PubMed

López-Torres, M; Pérez-Campo, R; Rojas, C; Cadenas, S; Barja, G

1993-08-01

Catalase was continuously inhibited with aminotriazole in the liver and kidney during 33 months in large populations of old and young frogs in order to study the effects of the modification of the tissue antioxidant/prooxidant balance on the life span of a vertebrate species showing an oxygen consumption rate similar to that of humans. Free-radical-related parameters were measured during three consecutive years at 2.5, 14.5, and 26.5 months of experimentation. Aging per se did not decrease antioxidant enzymes and did not increase peroxidation (thiobarbituric acid positive substances, or high-pressure liquid chromatography [HPLC]-malondialdehyde), either cross sectionally or longitudinally. Long-term catalase inhibition leads to time-dependent increases (100-900%) of endogenous superoxide dismutase, GSH, ascorbate, and especially glutathione reductase at 2.5 and 14.5 months of experimentation. This was positively correlated with a higher survival of treated animals (91% in treated versus 46% in controls at 14.5 months of experimentation). The loss of those inductions after 26.5 months leads to a sharp increase in mortality rate. The results show for the first time that simultaneous induction of various tissue antioxidant enzymes and nonenzymatic antioxidants can increase the mean life span of a vertebrate animal. It is concluded that the tissue antioxidant/prooxidant balance is a strong determinant of mean life span.

Ascorbic acid supplementation does not alter oxidative stress markers in healthy volunteers engaged in a supervised exercise program.

PubMed

Bunpo, Piyawan; Anthony, Tracy G

2016-02-01

The purpose of this study was to investigate the impact of ascorbic acid (AA) consumption on the oxidative stress status of untrained volunteers participating in a supervised exercise program. The study included 46 young adults (average age, 23.5 ± 0.59 years; 37 females, 9 males) who remained sedentary (n = 16) or participated in 30 min of outdoor aerobic running (n = 30) at an intensity corresponding to 65%-75% of maximum heart rate for 3 times per week for 12 weeks. Exercised subjects were randomly assigned to an exercise group without AA supplementation (control; n = 10) or received either 250 mg (n = 10) or 500 mg (n = 10) of AA supplementation previous to each exercise session. Blood samples were taken on day 0 and day 84 to evaluate metabolic profiles and antioxidant status. Sedentary subjects underwent in a single bout of aerobic running to determine total antioxidant status (TAS) and malondiadehyde (MDA) at pre- and postexercise with or without AA supplementation. No significant change in TAS was observed. Plasma MDA significantly increased at postexercise (P < 0.05), and AA supplementation decreased MDA level significantly (P < 0.05). After 3 months of exercise, there was no significant change in blood glucose, lipid profile, MDA, TAS, superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase activities amongst groups. Supplementation of AA was associated with minor and inconsistent reductions in SOD, GPx, and catalase activities (P < 0.05). These findings indicate that pre-exercise supplementation of ascorbic acid does not alter oxidative stress markers in the plasma and erythrocytes of young adults engaged in a supervised exercise program.

Polymethoxylated flavones, flavanone glycosides, carotenoids, and antioxidants in different cultivation types of tangerines ( Citrus reticulata Blanco cv. Sainampueng) from Northern Thailand.

PubMed

Stuetz, Wolfgang; Prapamontol, Tippawan; Hongsibsong, Surat; Biesalski, Hans-Konrad

2010-05-26

Polymethoxylated flavones (PMFs) and flavanone glycosides (FGs) were analyzed in hand-pressed juice and the peeled fruit of 'Sainampueng' tangerines ( Citrus reticulata Blanco cv. Sainampueng) grown in northern Thailand. The tangerines were collected from a citrus cluster of small orchard farmers and were cultivated as either agrochemical-based (AB), agrochemical-safe (AS), or organic grown fruits. Juice samples were also measured on contents of carotenoids, ascorbic acid, and tocopherols. The peel-deriving PMFs tangeretin, nobiletin, and sinensetin were found with high concentrations in juice as a result of simple squeezing, whereas amounts of those PMFs were negligibly low in peeled tangerine fruit. In contrast, the mean concentrations of the FGs narirutin, hesperidin, and didymin were several fold higher in peeled fruit than in tangerine juice and significantly higher in organic than AS and AB tangerines. Narirutin and hesperidin in juice from organic produces as well as narirutin in juice from AS produces were significantly higher than respective mean concentrations in juice from AB produces. beta-Cryptroxanthin was the predominant carotenoid beside zeaxanthin, lutein, lycopene, and beta-carotene in tangerine juice. Ascorbic acid concentrations were not predicted by the type of cultivation, whereas alpha-tocopherol was significantly higher in juice from organic than AS produces. In summary, hand-pressed juice of C. reticulata Blanco cv. Sainampueng serves as a rich source of PMFs, FGs, carotenoids, and antioxidants: 4-5 tangerine fruits ( approximately 80 g of each fruit) giving one glass of 200 mL hand-pressed juice would provide more than 5 mg of nobiletin and tangeretin and 36 mg of hesperidin, narirutin, and didymin, as well as 30 mg of ascorbic acid, >1 mg of provitamin A active beta-cryptoxanthin, and 200 microg of alpha-tocopherol.

In vitro health promoting properties of antioxidant dietary fiber extracted from spent coffee (Coffee arabica L.) grounds.

PubMed

Vázquez-Sánchez, Kenia; Martinez-Saez, Nuria; Rebollo-Hernanz, Miguel; Del Castillo, Maria Dolores; Gaytán-Martínez, Marcela; Campos-Vega, Rocio

2018-09-30

Antioxidant dietary fiber extracted from spent coffee grounds (FSCG) was evaluated as a potential functional food ingredient when incorporated in a food model (biscuits), and digested in vitro under simulated human gastrointestinal conditions. FSCG added to biscuits increased its total dietary fiber, antioxidant capacity after in vitro digestion, bioaccessibility of phenolic compounds (gallic acid and catechin) and amino acids. Furthermore, advanced glycation end products (AGEs), involved in chronic diseases, decreased up to 6-folds in the biscuits containing FSCG when compared with the traditional biscuit. The digestible fraction of biscuits containing the highest amount of FSCG (5 g) displayed the higher inhibiting α-glucosidase activity, correlating with the bioaccessibility of ascorbic acid and catechin. Our study seems to indicate that anti-diabetic compounds may be released in the small intestine during FSCG digestion, where biscuits containing FSCG may be able to beneficially regulate sugar metabolism thereby helping in producing foods friendly for diabetes. Copyright © 2018 Elsevier Ltd. All rights reserved.

Synthesis of Iminodiacetate Functionalized Polypropylene Films and Their Efficacy as Antioxidant Active-Packaging Materials.

PubMed

Lin, Zhuangsheng; Roman, Maxine J; Decker, Eric A; Goddard, Julie M

2016-06-08

The introduction of metal-chelating ligands to the food-contact surface of packaging materials may enable the removal of synthetic chelators (e.g., ethylenediamine tetra-acetic acid (EDTA)) from food products. In this study, the metal-chelating ligand iminodiacetate (IDA) was covalently grafted onto polypropylene surfaces to produce metal-chelating active-packaging films. The resulting films were able to chelate 138.1 ± 26 and 210.0 ± 28 nmol/cm(2) Fe(3+) and Cu(2+) ions, respectively, under acidic conditions (pH 3.0). The films demonstrated potent antioxidant efficacy in two model food systems. In an emulsified-oil system, the chelating materials extended the lag phase of both lipid hydroperoxide and hexanal formation from 5 to 25 days and were as effective as EDTA. The degradation half-life of ascorbic acid in an aqueous solution was extended from 5 to 14 days. This work demonstrates the potential application of surface-grafted chelating IDA ligands as effective antioxidant active food-packaging materials.

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

PubMed

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

2015-07-01

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

Effect of UV-C treatment on inactivation of Escherichia coli O157:H7, microbial loads, and quality of button mushrooms

USDA-ARS?s Scientific Manuscript database

This study investigated the effects of ultraviolet-C (UV-C) light applied to both sides of mushrooms on microbial loads and product quality during storage for 21 days at 4 C. Microflora populations, color, antioxidant activity, total phenolics, and ascorbic acid were measured at 1, 7, 14 and 21 days...

[Study on scavenging activity to DPPH free radical of different polarity components in Guizhou Miao medicine "bod zangd dak"].

PubMed

Du, Hong-zhi; Nong, Heng; Dong, Li-sha; Li, Jia-li; Liu, Ming; He, Xi-cheng; Zhang, Jing

2015-06-01

The paper is aimed to search more natural plant antioxidants and further research and develop new medicinal plant resources in Guizhou. The Guizhou special miao medicine "bod zangd dak" was extracted with 60% ethanol. The antioxidant activity of the different polarity components separated from the extract was tested by DPPH method with ascorbic acid as positive control. The results showed that the IC50 of the different polarity components was as following: ascorbic acid (0.033 4 g x L(-1)) < ethyl acetate components (0.052 3 g x L(-1)) < total tannins components (0.054 9 g x L(-1)) < 60% ethanol extraction components (0.076 7 g x L(-1)) < butanol extraction components (0.110 g x L(-1)) < water-soluble polysaccharides components (0.168 g x L(-1)) < water extraction components (0.174 g x L(-1)) < water components after extraction (0.226 g x L(-1)) < total polysaccharides components (0.645 g x L(-1)). It is concluded that the different polarity components have different free radical scavenging activity and that provides a scientific basis for further search of the active ingredients and the activive mechanism.

Bioactive Compounds and Fruit Quality of Green Sweet Pepper Grown under Different Colored Shade Netting during Postharvest Storage.

PubMed

Mashabela, Madonna N; Selahle, Kamogelo M; Soundy, Puffy; Crosby, Kevin M; Sivakumar, Dharini

2015-11-01

In this study, influence of 3 types of photo-selective nets (pearl, red and yellow) and a standard black net on marketable yield, fruit quality and bioactive compounds after postharvest storage was investigated. Percentage marketable fruits were higher in green sweet peppers produced under the pearl nets. Fruits produced under the pearl nets showed higher fruit mass, firmness, chlorophyll content, ascorbic acid content, antioxidant scavenging activity after postharvest storage. Red/far red photon ratio under the pearl net could have improved the ascorbic acid content and the antioxidant scavenging activity in green peppers. Green sweet peppers grown under the pearl nets had higher hue values and maintained green color longer. Our results showed the impact of modified light quality on the bioactive compounds of green sweet pepper during postharvest storage. Green sweet peppers are rich in phytochemicals. Marketability of green sweet peppers is affected partially due to ripening after postharvest storage and decay. Maintenance of green color, fruit mass, firmness, and nutritional composition are important parameters that attract consumers. This research shows the influence of light quality during production on the fruit quality parameters and bioactive compounds after postharvest storage. © 2015 Institute of Food Technologists®

Study of lipid peroxidation and ascorbic acid protective role in large unilamellar vesicles from a new electrochemical performance.

PubMed

Barroso, M Fátima; Luna, M Alejandra; Moyano, Fernando; Delerue-Matos, Cristina; Correa, N Mariano; Molina, Patricia G

2018-04-01

In this contribution an electrochemical study is described for the first time of lipid peroxidation and the role of antioxidant on lipid protection using large unilamellar vesicles (LUVs). In order to simulate the cell membrane, LUVs composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) were used. A vesicle-modified electrode was constructed by immobilizing DOPC LUVs onto carbon paste electrodes (CPEs). Lipid peroxidation was studied electrochemically by incubating the vesicle-modified electrodes with hydroxyl (HO) radicals generated via the Fenton reaction. Oxidative damage induced by HO was verified by using square wave voltammetry (SWV) and was indirectly measured by the increase of electrochemical peak current to [Fe(CN) 6 ] 4- which was used as the electrochemical label. Ascorbic acid (AA) was used as the antioxidant model in order to study its efficacy on free radical scavenging. The decrease of the electrochemical signal confirms the protective key role promoted by AA in the prevention of lipid peroxidation in vesicles. Through microscopy, it was possible to observe morphologic modification on vesicle structures after lipid peroxidation in the presence or absence of AA. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of Nigella sativa oil and ascorbic acid against oxytetracycline-induced hepato-renal toxicity in rabbits.

PubMed

Abdel-Daim, Mohamed M; Ghazy, Emad W

2015-03-01

Oxytetracycline (OTC) is a broad spectrum antibiotic widely used for treatment of a wide range of infections. However, its improper human and animal use leads to toxic effects, including hepatonephrotoxicity. Our objective was to evaluate protective effects of Nigella sativa oil (NSO) and/or ascorbic acid (AA), against OTC-induced hepatonephrotoxicity in rabbits. Forty male white New Zealand rabbits were divided into 5 groups of eight each. The 1(st) group (control) was given saline. The 2(nd) group was given OTC (200 mg/kg, orally). The 3(rd) and 4(th) groups were orally administered NSO and AA (2 ml/kg and 200 mg/kg respectively) 1 hr before OTC administration at the same dose regimen used for the 2(nd) group. Both NSO and AA were given in combination for the 5(th) group along with OTC administration. Serum biochemical parameters related to liver and kidney injury were evaluated, and lipid peroxidation as well as antioxidant markers in hepatic and renal tissues were examined. OTC-treated animals revealed significant alterations in serum biochemical hepato-renal injury markers, and showed a markedly increase in hepato-renal lipid peroxidation and inhibition in tissue antioxidant biomarkers. NSO and AA protect against OTC-induced serum and tissue biochemical alterations when each of them is used alone or in combination along with OTC treatment. Furthermore, both NSO and AA produced synergetic hepatoprotective and antioxidant properties. The present study revealed the preventive role of NSO and/or AA against the toxic effects of OTC through their free radical-scavenging and potent antioxidant activities.

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

PubMed

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

2017-11-01

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

Use of lyophilised and powdered Gentiana lutea root in fresh beef patties stored under different atmospheres.

PubMed

Azman, Nurul A M; Gordon, Michael H; Skowyra, Monika; Segovia, Francisco; Almajano, María Pilar

2015-07-01

Gentiana lutea root is a medicinal herb that contains many active compounds which contribute to physiological effects, and it has recently attracted much attention as a natural source of antioxidants. The aim of this study was to evaluate the effects on the colour, pH, microbial activities, sensory quality and resistance to lipid oxidation (through the thiobarbituric acid method) during storage of beef patties containing different concentrations of G. lutea. Fresh beef patties were formulated with 0-5 g kg(-1) of G. lutea and 0 or 0.5 g kg(-1) of ascorbic acid and packed in two different atmospheres, Modified Atmosphere 1 (MAP1) and Modified Atmosphere 2 (MAP2), and stored at 4 ± 1 °C for 10 days. MAP1 contained 20:80 (v/v) O2:CO2 and MAP2 contained 80:20 (v/v) O2:CO2. G. lutea extracts possessed antioxidant activity measured by the ferric reducing antioxidant power and the oxygen radical absorbance capacity assays. Beef patties containing 2 g kg(-1) of lyophilised G. lutea were stable towards lipid oxidation in both atmospheres (P < 0.05). Beef patties containing a combination of 2 g kg(-1) G. lutea and 0.5 g kg(-1) ascorbic acid showed significantly reduced changes in colour and in lipid oxidation (P < 0.05). The results from this study demonstrate the potential of G. lutea as a food ingredient in the design of healthier meat commodities. © 2014 Society of Chemical Industry.

Targeting excessive free radicals with peels and juices of citrus fruits: grapefruit, lemon, lime and orange.

PubMed

Guimarães, Rafaela; Barros, Lillian; Barreira, João C M; Sousa, M João; Carvalho, Ana Maria; Ferreira, Isabel C F R

2010-01-01

A comparative study between the antioxidant properties of peel (flavedo and albedo) and juice of some commercially grown citrus fruit (Rutaceae), grapefruit (Citrus paradisi), lemon (Citrus limon), lime (Citrusxaurantiifolia) and sweet orange (Citrus sinensis) was performed. Different in vitro assays were applied to the volatile and polar fractions of peels and to crude and polar fraction of juices: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, reducing power and inhibition of lipid peroxidation using beta-carotene-linoleate model system in liposomes and thiobarbituric acid reactive substances (TBARS) assay in brain homogenates. Reducing sugars and phenolics were the main antioxidant compounds found in all the extracts. Peels polar fractions revealed the highest contents in phenolics, flavonoids, ascorbic acid, carotenoids and reducing sugars, which certainly contribute to the highest antioxidant potential found in these fractions. Peels volatile fractions were clearly separated using discriminant analysis, which is in agreement with their lowest antioxidant potential. Copyright 2009 Elsevier Ltd. All rights reserved.

Ultraviolet Irradiation Effect on Apple Juice Bioactive Compounds during Shelf Storage

PubMed Central

Juarez-Enriquez, Edmundo; Salmerón, Ivan; Gutierrez-Mendez, Nestor; Ortega-Rivas, Enrique

2016-01-01

Clarified and standardized apple juice was ultraviolet-irradiated to inactivate polyphenol oxidase enzyme and microbiota, and its effect on bioactive compounds and stability during storage was also evaluated. Apple juice was irradiated with 345.6 J/cm2 and treatment effect was evaluated in terms of color, antioxidant capacity, polyphenol content, pH, titratable acidity and total soluble solids. Using a linear regression design, inactivation kinetic of polyphenol oxidase enzyme was also described. In addition, a repeated measures design was carried out to evaluate apple juice during 24 days of storage at 4 °C and 20 °C. After irradiation, reduction of antioxidant capacity was observed while during storage, ascorbic acid content decreased up to 40% and total polyphenol content remain stable. Ultraviolet irradiation achieved a complete inactivation of polyphenol oxidase enzyme and microbiota, keeping apple juice antioxidants during ultraviolet treatment and storage available until juice consumption. UV-treated apple juice can be used as a regular beverage, ensuring antioxidant intake. PMID:28231106

Chemical composition and antioxidant activity of essential oil from leaves and rhizomes of Curcuma angustifolia Roxb.

PubMed

Jena, Sudipta; Ray, Asit; Banerjee, Anwesha; Sahoo, Ambika; Nasim, Noohi; Sahoo, Suprava; Kar, Basudeba; Patnaik, Jeetendranath; Panda, Pratap Chandra; Nayak, Sanghamitra

2017-09-01

The essential oil extracted from rhizome and leaf of Curcuma angustifolia Roxb. (Zingiberaceae) was characterised by gas chromatography-mass spectrometry (GC-MS). The GC-MS analysis revealed the presence of 32 and 35 identified constituents, comprising 92.6% and 92% of total leaf and rhizome oil, respectively. Curzerenone (33.2%), 14-hydroxy-δ-cadinene (18.6%) and γ-eudesmol acetate (7.3%) were the main components in leaf oil. In rhizome oil, curzerenone (72.6%), camphor (3.3%) and germacrone (3.3%) were found to be the major constituents. Antioxidant capacities of oil were assessed by various methods, 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and reducing power ability (RPA). Based on the results, the leaf oil showed more antioxidant potential as compared to rhizome oil and reference standards (ascorbic acid and butylated hydroxytoluene (BHT)). Thus, the leaf essential oil of C. angustifolia can be used as an alternative source of natural antioxidant.

Insights on Antioxidant Assays for Biological Samples Based on the Reduction of Copper Complexes—The Importance of Analytical Conditions

PubMed Central

Marques, Sara S.; Magalhães, Luís M.; Tóth, Ildikó V.; Segundo, Marcela A.

2014-01-01

Total antioxidant capacity assays are recognized as instrumental to establish antioxidant status of biological samples, however the varying experimental conditions result in conclusions that may not be transposable to other settings. After selection of the complexing agent, reagent addition order, buffer type and concentration, copper reducing assays were adapted to a high-throughput scheme and validated using model biological antioxidant compounds of ascorbic acid, Trolox (a soluble analogue of vitamin E), uric acid and glutathione. A critical comparison was made based on real samples including NIST-909c human serum certified sample, and five study samples. The validated method provided linear range up to 100 µM Trolox, (limit of detection 2.3 µM; limit of quantification 7.7 µM) with recovery results above 85% and precision <5%. The validated developed method with an increased sensitivity is a sound choice for assessment of TAC in serum samples. PMID:24968275

Biochemical Characterization and Antimicrobial and Antifungal Activity of Two Endemic Varieties of Garlic (Allium sativum L.) of the Campania Region, Southern Italy.

PubMed

Fratianni, Florinda; Riccardi, Riccardo; Spigno, Patrizia; Ombra, Maria Neve; Cozzolino, Autilia; Tremonte, Patrizio; Coppola, Raffaele; Nazzaro, Filomena

2016-07-01

Extracts of the bulbs of the two endemic varieties "Rosato" and "Caposele" of Allium sativum of the Campania region, Southern Italy, were analyzed. The phenolic content, ascorbic acid, allicin content, and in vitro antimicrobial and antifungal activity were determined. Ultra performance liquid chromatography with diode array detector performed polyphenol profile. The polyphenolic extracts showed antioxidant activity (EC50) lower than 120 mg. The amount of ascorbic acid and allicin in the two extracts was similar. Polyphenol extract exhibited antimicrobial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and (only by the extract of Rosato) against Bacillus cereus. The extract of Caposele was more effective in inhibiting the growth of Aspergillus versicolor and Penicillum citrinum. On the other hand, the extract of Rosato was effective against Penicillium expansum.

Oxidative stress and antioxidant defenses in pregnant women.

PubMed

Leal, Claudio A M; Schetinger, Maria R C; Leal, Daniela B R; Morsch, Vera M; da Silva, Aleksandro Schafer; Rezer, João F P; de Bairros, André Valle; Jaques, Jeandre Augusto Dos Santos

2011-01-01

Oxidative stress (OS) is defined as an imbalance in the production of reactive oxygen species and the capacity of antioxidant defenses. The objective of this work was to investigate OS and antioxidant capacity in pregnant women. Parameters of the oxidative status and antioxidant capacity in serum and whole blood were evaluated in thirty-nine women with normal pregnancy. The assessment of antioxidants indicated an increase in superoxide dismutase and catalase activities (P<0.05 and P<0.01) and a decrease in ascorbic acid levels and the total content of sulfhydryl (P<0.05 and P<0.001). Additionally, when the pro-oxidant system was investigated we found an increase (P<0.01) in malondialdehyde and no significant change (P>0.05) in protein carbonylation. This study demonstrates that there is a change in the pro-oxidant and antioxidant defenses associated with body and circulation changes that are inherent to the pregnancy process.

Enhancement of nutritional and bioactive compounds by in vitro culture of wild Fragaria vesca L. vegetative parts.

PubMed

Dias, Maria Inês; Barros, Lillian; Sousa, Maria João; Oliveira, M Beatriz P P; Santos-Buelga, Celestino; Ferreira, Isabel C F R

2017-11-15

In vitro culture emerges as a sustainable way to produce bioactives for further applicability in the food industry. Herein, vegetative parts of Fragaria vesca L. (wild strawberry) obtained by in vitro culture were analyzed regarding nutritional and phytochemical compounds, as well as antioxidant activity. These samples proved to have higher content of protein, polyunsaturated fatty acids, soluble sugars, organic acids (including ascorbic acid) and tocopherols (mainly α-tocopherol) than wild grown F. vesca, as well as containing additional phenolic compounds. The antioxidant activity of hydromethanolic extracts could be correlated with the content of different phenolic groups and other compounds (sugars and organic acids). It was demonstrated that in vitro culture could enhance nutritional and bioactive compounds of Fragaria vesca L. plants, providing a very interesting biotechnological tool for potential food applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bioactive Compounds and Antioxidant Activity in Different Types of Berries

PubMed Central

Skrovankova, Sona; Sumczynski, Daniela; Mlcek, Jiri; Jurikova, Tunde; Sochor, Jiri

2015-01-01

Berries, especially members of several families, such as Rosaceae (strawberry, raspberry, blackberry), and Ericaceae (blueberry, cranberry), belong to the best dietary sources of bioactive compounds (BAC). They have delicious taste and flavor, have economic importance, and because of the antioxidant properties of BAC, they are of great interest also for nutritionists and food technologists due to the opportunity to use BAC as functional foods ingredients. The bioactive compounds in berries contain mainly phenolic compounds (phenolic acids, flavonoids, such as anthocyanins and flavonols, and tannins) and ascorbic acid. These compounds, either individually or combined, are responsible for various health benefits of berries, such as prevention of inflammation disorders, cardiovascular diseases, or protective effects to lower the risk of various cancers. In this review bioactive compounds of commonly consumed berries are described, as well as the factors influencing their antioxidant capacity and their health benefits. PMID:26501271

Constituents and Antioxidant Activity of Bleeding Sap from Various Xinjiang Grapes.

PubMed

Le, Lv; Umar, Anwar; Iburaim, Arkin; Moore, Nicholas

2017-10-01

Wine grape sap or bleeding sap of grapes (GBS) is commonly used in Xinjiang (China) for therapeutic aims. Do variations in composition related to region and variety affect its properties? GBS samples originating in various parts of Xinjiang (Turpan, Hotan, Kashgar, and Atush) were tested for phenols and polyphenols, polysaccharides, saponin, proteins, individual amino acids, and minerals. Their antioxidant activity was measured using ascorbic acid as reference. Polyphenol content varied from 2.6 to 6.6 mg/L, polysaccharides 18.3-816 mg/L, saponin 6.25-106 mg/L, and protein 3.0-22.4 mg/L. Mineral elements and amino acids ranged from 6.20 to 201.2 mg/L and 0.06-118.7 mg/L, respectively. ·OH scavenging ability varied from 70% to over 90%, higher than Vitamin C. Grapes from Turpan had lower antioxidant activity than other grapes even though the polyphenol content was generally higher. Bleeding sap of Xinjiang grape is rich in amino acids, polysaccharides, polyphenols, and protein. The contents are different according to the origin, related possibly to species, climate, and environment. Antioxidant effects were not correlated with polyphenol content. Antioxidant activity of plants or plant extracts is often associated with polyphenolsBleeding sap of grapes has strong antioxidant propertiesBleeding sap from different grape varieties from different parts of Xinjiang (China) had different polyphenol concentrationsThere was no correlation of polyphenol concentrations with antioxidant activity. Abbreviations used: GBS: Bleeding sap of grapes; PITC: phenyl isothiocyanate.

Antioxidant Capability of Ultra-high Temperature Milk and Ultra-high Temperature Soy Milk and their Fermented Products Determined by Four Distinct Spectrophotometric Methods

PubMed Central

Baghbadorani, Sahar Torki; Ehsani, Mohammad Reza; Mirlohi, Maryam; Ezzatpanah, Hamid; Azadbakht, Leila; Babashahi, Mina

2017-01-01

Background: Due to the recent emerging information on the antioxidant properties of soy products, substitution of soy milk for milk in the diet has been proposed by some nutritionists. We aimed to compare four distinct antioxidant measuring methods in the evaluation of antioxidant properties of industrial ultra-high temperature (UHT) milk, UHT soy milk, and their fermented products by Lactobacillus plantarum A7. Materials and Methods: Ascorbate auto-oxidation inhibition assay, 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical scavenging method, hydrogen peroxide neutralization assay and reducing activity test were compared for the homogeneity and accuracy of the results. Results: The results obtained by the four tested methods did not completely match with each other. The results of the DPPH assay and the reducing activity were more coordinated than the other methods. By the use of these methods, the antioxidant capability of UHT soy milk was measured more than UHT milk (33.51 ± 6.00% and 945 ± 56 μM cysteine compared to 8.70 ± 3.20% and 795 ± 82 μM cysteine). The negative effect of fermentation on the antioxidant potential of UHT soy milk was revealed as ascorbate auto-oxidation inhibition assay, DPPH method and reducing activity tests ended to approximately 52%, 58%, and 80% reduction in antioxidant potential of UHT soy milk, respectively. Conclusions: The antioxidative properties of UHT soy milk could not be solely due to its phenolic components. Peptides and amino acids derived from thermal processing in soy milk probably have a main role in its antioxidant activity, which should be studied in the future. PMID:28603703

Changes in the Aromatic Profile, Sugars, and Bioactive Compounds When Purple Garlic Is Transformed into Black Garlic.

PubMed

Martínez-Casas, Lucía; Lage-Yusty, María; López-Hernández, Julia

2017-12-13

Black garlic is an elaborated product obtained from fresh garlic (Allium sativum L.) at a controlled high humidity and temperature, which leads to modifications in color, taste, and texture. To clarify the physicochemical changes that occur during the thermal process, this work aimed to evaluate and contrast the antioxidant capacity and that of other compounds between purple garlic ecotype "Purple from Las Pedroñeras" and its black garlic derivative. Our results showed numerous differences between both, because black garlic presented a significant divergence in its volatile profile, a decreased amount of ascorbic acid, an increment in sugar and polyphenol contents, a greater antioxidant capacity, and a different composition of phenolic acids and flavonoids.

Barley yellow dwarf virus infection and elevated CO2 alter the antioxidants ascorbate and glutathione in wheat.

PubMed

Vandegeer, Rebecca K; Powell, Kevin S; Tausz, Michael

2016-07-20

Plant antioxidants ascorbate and glutathione play an important role in regulating potentially harmful reactive oxygen species produced in response to virus infection. Barley yellow dwarf virus is a widespread viral pathogen that systemically infects cereal crops including wheat, barley and oats. In addition, rising atmospheric CO 2 will alter plant growth and metabolism, including many potential but not well understood effects on plant-virus interactions. In order to better understand the wheat-BYDV interaction and any potential changes under elevated CO 2 , the total concentration and oxidised fraction of ascorbate and glutathione was measured in leaves of a susceptible wheat cultivar (Triticum aestivum L. 'Yitpi') infected with Barley yellow dwarf virus-PAV (Padi Avenae virus) and grown under elevated CO 2 in controlled environment chambers. Virus infection decreased total leaf ascorbate and glutathione concentrations and increased the fraction of oxidised ascorbate (dehydroascorbate). Elevated CO 2 decreased the fraction of oxidised ascorbate. In this work, we demonstrate that systemic infection by a phloem-restricted virus weakens the antioxidant pools of ascorbate and glutathione. In addition, elevated CO 2 may decrease oxidative stress, for example, from virus infection, but there was no direct evidence for an interactive effect between treatments. Copyright © 2016 Elsevier GmbH. All rights reserved.

Cupric ion reducing antioxidant capacity assay for antioxidants in human serum and for hydroxyl radical scavengers.

PubMed

Apak, Reşat; Güçlü, Kubilay; Ozyürek, Mustafa; Bektaşoğlu, Burcu; Bener, Mustafa

2010-01-01

Tests measuring the combined antioxidant effect of the nonenzymatic defenses in biological fluids may be useful in providing an index of the organism's capability to counteract reactive species known as pro-oxidants, resist oxidative damage, and combat oxidative stress-related diseases. The selected chromogenic redox reagent for the assay of human serum should be easily accessible, stable, selective, and respond to all types of biologically important antioxidants such as ascorbic acid, alpha-tocopherol, beta-carotene, reduced glutathione (GSH), uric acid, and bilirubin, regardless of chemical type or hydrophilicity. Our recently developed cupric reducing antioxidant capacity (CUPRAC) spectrophotometric method for a number of polyphenols and flavonoids using the copper(II)-neocuproine reagent in ammonium acetate buffer is now applied to a complete series of plasma antioxidants for the assay of total antioxidant capacity of serum, and the resulting absorbance at 450 nm is recorded either directly (e.g., for ascorbic acid, alpha-tocopherol, and glutathione) or after incubation at 50 degrees C for 20 min (e.g., for uric acid, bilirubin, and albumin), quantitation being made by means of a calibration curve. The lipophilic antioxidants, alpha-tocopherol and beta-carotene, are assayed in dichloromethane. Lipophilic antioxidants of serum are extracted with n-hexane from an ethanolic solution of serum subjected to centrifugation. Hydrophilic antioxidants of serum are assayed in the centrifugate after perchloric acid precipitation of proteins. The CUPRAC molar absorptivities, linear ranges, and TEAC (trolox equivalent antioxidant capacity) coefficients of the serum antioxidants are established, and the results are evaluated in comparison with the findings of the ABTS/TEAC reference method. The intra- and inter-assay coefficients of variation (CVs) are 0.7 and 1.5%, respectively, for serum. The CUPRAC assay proved to be efficient for glutathione and thiol-type antioxidants, for which the FRAP (ferric reducing antioxidant potency) test is basically nonresponsive. The additivity of absorbances of all the tested antioxidants confirmed that antioxidants in the CUPRAC test do not chemically interact among each other so as to cause an intensification or quenching of the theoretically expected absorbance, and that a total antioxidant capacity (TAC) assay of serum is possible. As a distinct advantage over other electron-transfer based assays (e.g., Folin, FRAP, ABTS, DPPH), CUPRAC is superior in regard to its realistic pH close to the physiological pH, favorable redox potential, accessibility and stability of reagents, and applicability to lipophilic antioxidants as well as hydrophilic ones. The CUPRAC procedure can also assay hydroxyl radicals, being the most reactive oxygen species (ROS). As a more convenient, efficient, and less costly alternative to HPLC/electrochemical detection techniques and to the nonspecific, low-yield TBARS test, we use p-aminobenzoate, 2,4- and 3,5-dimethoxybenzoate probes for detecting hydroxyl radicals generated from an equivalent mixture of [Fe(II)+EDTA] with hydrogen peroxide. The produced hydroxyl radicals attack both the probe and the water-soluble antioxidants in 37 degrees C-incubated solutions for 2 h. The CUPRAC absorbance of the ethylacetate extract due to the reduction of Cu(II)-neocuproine reagent by the hydroxylated probe decreases in the presence of (.)OH scavengers, the difference being proportional to the scavenging ability of the tested compound. The developed method is less lengthy, more specific, and of a higher yield than the classical TBARS assay.

Red Orange: Experimental Models and Epidemiological Evidence of Its Benefits on Human Health

PubMed Central

Galvano, Fabio; Mistretta, Antonio; Marventano, Stefano; Nolfo, Francesca; Calabrese, Giorgio; Buscemi, Silvio; Drago, Filippo; Veronesi, Umberto; Scuderi, Alessandro

2013-01-01

In recent years, there has been increasing public interest in plant antioxidants, thanks to the potential anticarcinogenic and cardioprotective actions mediated by their biochemical properties. The red (or blood) orange (Citrus sinensis (L.) Osbeck) is a pigmented sweet orange variety typical of eastern Sicily (southern Italy), California, and Spain. In this paper, we discuss the main health-related properties of the red orange that include anticancer, anti-inflammatory, and cardiovascular protection activities. Moreover, the effects on health of its main constituents (namely, flavonoids, carotenoids, ascorbic acid, hydroxycinnamic acids, and anthocyanins) are described. The red orange juice demonstrates an important antioxidant activity by modulating many antioxidant enzyme systems that efficiently counteract the oxidative damage which may play an important role in the etiology of numerous diseases, such as atherosclerosis, diabetes, and cancer. The beneficial effects of this fruit may be mediated by the synergic effects of its compounds. Thus, the supply of natural antioxidant compounds through a balanced diet rich in red oranges might provide protection against oxidative damage under differing conditions and could be more effective than, the supplementation of an individual antioxidant. PMID:23738032

Comparative Evaluation of Polyphenol Contents and Antioxidant Activities between Ethanol Extracts of Vitex negundo and Vitex trifolia L. Leaves by Different Methods.

PubMed

Saklani, Sarla; Mishra, Abhay Prakash; Chandra, Harish; Atanassova, Maria Stefanova; Stankovic, Milan; Sati, Bhawana; Shariati, Mohammad Ali; Nigam, Manisha; Khan, Mohammad Usman; Plygun, Sergey; Elmsellem, Hicham; Suleria, Hafiz Ansar Rasul

2017-09-27

The in vitro antioxidant potential assay between ethanolic extracts of two species from the genus Vitex ( Vitex negundo L. and Vitex trifolia L.) belonging to the Lamiaceae family were evaluated. The antioxidant properties of different extracts prepared from both plant species were evaluated by different methods. DPPH scavenging, nitric oxide scavenging, and β-carotene-linoleic acid and ferrous ion chelation methods were applied. The antioxidant activities of these two species were compared to standard antioxidants such as butylated hydroxytoluene (BHT), ascorbic acid, and Ethylene diamine tetra acetic acid (EDTA). Both species of Vitex showed significant antioxidant activity in all of the tested methods. As compared to V. trifolia L. (60.87-89.99%; 40.0-226.7 μg/mL), V. negundo has been found to hold higher antioxidant activity (62.6-94.22%; IC 50 = 23.5-208.3 μg/mL) in all assays. In accordance with antioxidant activity, total polyphenol contents in V. negundo possessed greater phenolic (89.71 mg GAE/g dry weight of extract) and flavonoid content (63.11 mg QE/g dry weight of extract) as compared to that of V. trifolia (77.20 mg GAE/g and 57.41 mg QE/g dry weight of extract respectively). Our study revealed the significant correlation between the antioxidant activity and total phenolic and flavonoid contents of both plant species.

Association between circulating ascorbic acid, α-tocopherol, 25-hydroxyvitamin D, and plasma cytokine concentrations in young adults: a cross-sectional study.

PubMed

García-Bailo, Bibiana; Roke, Kaitlin; Mutch, David M; El-Sohemy, Ahmed; Badawi, Alaa

2012-11-16

Inflammation and oxidative stress are associated with the development of numerous chronic diseases. Circulating ascorbic acid, α-tocopherol, and 25-hydroxyvitamin D (25(OH)D) may help reduce concentrations of pro-inflammatory cytokines through their antioxidant and anti-inflammatory properties. These micronutrients may act synergistically, and they may have different anti-inflammatory effects, but previous studies have assessed the link between each of these micronutrients and inflammation in isolation without controlling for the other micronutrients. Our objective was to examine the association between circulating concentrations of ascorbic acid, α-tocopherol, and 25(OH) D and a panel of pro-inflammatory cytokines in an ethnically diverse population of young adults. Participants (n = 1,007) from the Toronto Nutrigenomics and Health study provided fasting blood samples for biomarker measurements and were subsequently categorized into tertiles for each micronutrient based on their circulating concentrations. We conducted Pearson's correlation analyses across all micronutrients and cytokines. The associations between individual micronutrients and cytokines were examined using analysis of covariance with age, sex, waist circumference, ethnicity, physical activity, season of blood collection, total cholesterol, hormonal contraceptive use among women, and the other two micronutrients as covariates. We observed weak micronutrient-cytokine correlations, moderate correlations between certain cytokines, and strong correlations between specific cytokines, particularly interleukin 1- receptor antagonist (IL-1RA), interferon-γ (IFN-γ), and platelet-derived growth factor BB (PDGF-bb). After full covariate adjustment, circulating α-tocopherol was inversely associated with IFN-γ and regulated upon activation normal T-cell expressed and secreted (RANTES). We observed an unexpected positive association between ascorbic acid and IFN-γ. 25(OH)D was not associated with altered concentrations of any inflammatory biomarkers. These findings suggest that α-tocopherol, but not ascorbic acid or 25(OH)D, is inversely associated with inflammation in healthy young adults.

Antioxidant capacity of pure compounds and complex mixtures evaluated by the ORAC-pyrogallol red assay in the presence of Triton X-100 micelles.

PubMed

Romero, Max; Rojano, Benjamin; Mella-Raipán, Jaime; Pessoa-Mahana, Carlos David; Lissi, Eduardo; López-Alarcón, Camilo

2010-09-01

The protective effect of different antioxidants and complex mixtures on the consumption of pyrogallol red (PGR) induced by peroxyl radicals was studied in the absence and presence of Triton X-100 micelles. The presence of micelles decreased significantly the protection of PGR afforded by lipophilic antioxidants (β-carotene, octyl gallate), while no effect of micelles was observed for hydrophilic antioxidants such as Trolox, caffeic acid, gallic acid, and ascorbic acid. In the presence of complex mixtures a clear effect of Triton X-100 micelles was also observed in the protection afforded by wines, tea infusions, and seed extracts of Eugenia jambolana and Myrciaria cauliflora. On the other hand, no effect of micelles was observed for orange juice and pulp fruit extracts. The ORAC (Oxygen Radical Absorbance Capacity) index was evaluated in the absence (ORAC-PGR) and presence of Triton X-100 micelles (ORAC-PGR(MIC)). Triton X-100 micelles affect ORAC-PGR values of antioxidants in a lipophilicity-dependent way. From the obtained results, we conclude that ORAC-PGR and ORAC-PGR(MIC) assays could be considered as an alternative to estimate the antioxidant ability (ORAC-PGR) and to infer the association to Triton X-100 micelles (ORAC-PGR/ORAC-PGR(MIC)) of pure antioxidants and their complex mixtures.

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

PubMed

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

2011-04-01

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

Antioxidant delivery pathways in the anterior eye.

PubMed

Umapathy, Ankita; Donaldson, Paul; Lim, Julie

2013-01-01

Tissues in the anterior segment of the eye are particular vulnerable to oxidative stress. To minimise oxidative stress, ocular tissues utilise a range of antioxidant defence systems which include nonenzymatic and enzymatic antioxidants in combination with repair and chaperone systems. However, as we age our antioxidant defence systems are overwhelmed resulting in increased oxidative stress and damage to tissues of the eye and the onset of various ocular pathologies such as corneal opacities, lens cataracts, and glaucoma. While it is well established that nonenzymatic antioxidants such as ascorbic acid and glutathione are important in protecting ocular tissues from oxidative stress, less is known about the delivery mechanisms used to accumulate these endogenous antioxidants in the different tissues of the eye. This review aims to summarise what is currently known about the antioxidant transport pathways in the anterior eye and how a deeper understanding of these transport systems with respect to ocular physiology could be used to increase antioxidant levels and delay the onset of eye diseases.

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

PubMed Central

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

2013-01-01

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

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

PubMed

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

2013-02-01

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

Discovery of C-3 tethered 2-oxo-benzo[1,4]oxazines as potent antioxidants: Bio-inspired based design, synthesis, biological evaluation, cytotoxic and Insilico molecular docking studies

NASA Astrophysics Data System (ADS)

Sharma, Vashundhra; Jaiswal, Pradeep K.; Saran, Mukesh; Yadav, Dharmendra Kumar; Saloni; Mathur, Manas; Swami, Ajit K.; Misra, Sanjeev; Kim, Mi-hyun; Chaudhary, Sandeep

2018-03-01

The discovery of C-3 tethered 2-oxo-benzo[1,4]oxazines as potent antioxidants is disclosed. All the analogues 20a-20ab have been synthesized via “on water” ultrasound-assisted in excellent yields (upto 98%). All the compounds have been evaluated for their in vitro antioxidant activities using DPPH free radical scavenging assay as well as FRAP assay. The result showed promising antioxidant activities having IC50 values in the range of 4.74 ± 0.08 to 92.20 ± 1.54 μg/mL taking ascorbic acid (IC50 = 4.57 μg/mL) as standard reference. In this study, compounds 20b and 20t, the most active compound of the series, showed IC50 values of 6.89 ± 0.07μg/mL and 4.74 ± 0.08 μg/mL, respectively in comparison with ascorbic acid. In addition, the detailed SAR study shows that electron-withdrawing group increases antioxidant activity and vice versa. Furthermore, in the FRAP assay, eight compounds (20c, 20j, 20m, 20n, 20r, 20u, 20z and 20aa) were found more potent than standard reference BHT (C0.5FRAP = 546.0 ± 13.6 μM). The preliminary cytotoxic study reveals the non-toxic nature of active compounds 20b and 20t in non-cancerous 3T3 fibroblast cell lines in MTT assay up to 250 μg/mL concentration. The results were validated via carrying out insilico molecular docking studies of promising compounds 20a, 20b and 20t in comparison with standard reference. To the best of our knowledge, this is the first detailed study of C-3 tethered 2-oxo-benzo[1,4]oxazines as potential antioxidant agents.

Effect of stationary magnetic field strengths of 150 and 200 mT on reactive oxygen species production in soybean.

PubMed

Shine, M B; Guruprasad, K N; Anand, Anjali

2012-07-01

Our previous investigation reported the beneficial effect of pre-sowing magnetic treatment for improving germination parameters and biomass accumulation in soybean. In this study, soybean seeds treated with static magnetic fields of 150 and 200 mT for 1 h were evaluated for reactive oxygen species (ROS) and activity of antioxidant enzymes. Superoxide and hydroxyl radicals were measured in embryos and hypocotyls of germinating seeds by electron paramagnetic resonance spectroscopy and kinetics of superoxide production; hydrogen peroxide and antioxidant activities were estimated spectrophotometrically. Magnetic field treatment resulted in enhanced production of ROS mediated by cell wall peroxidase while ascorbic acid content, superoxide dismutase and ascorbate peroxidase activity decreased in the hypocotyl of germinating seeds. An increase in the cytosolic peroxidase activity indicated that this antioxidant enzyme had a vital role in scavenging the increased H(2)O(2) produced in seedlings from the magnetically treated seeds. Hence, these studies contribute to our first report on the biochemical basis of enhanced germination and seedling growth in magnetically treated seeds of soybean in relation to increased production of ROS. Copyright © 2012 Wiley Periodicals, Inc.

[Effect of simulative warming on growth and antioxidative characteristics of Kobresia pygmaea and K. tibetica in the permafrost region of Qinghai-Tibetan Plateau, China].

PubMed

Xiao, Yao; Wang, Gen Xu; Yang, Yan; Yang, Yang; Peng, A Hui; Zhang, Li

2017-04-18

In the present study, open top chambers (OTCs) were employed to simulate temperature increase at Fenghuoshan site, located on the hinterland of Qinghai-Tibetan Plateau. To explore the potential response mechanism of alpine plants under warmer temperature, the leaf morphological and antioxidative characteristics of two dominant species of alpine meadow (Kobresia pygmaea) and alpine swamp meadow (K. tibetica) were analyzed. The results showed that length and numbers of leaves in K. pygmaea increased by 40.0% and 72.7% by warming, respectively. Plant height and leaf length in K. tibetica increased by 11.9% and 19.3% by warming, respectively. Warming improved plant growth and aboveground biomass accumulation in both species. However, warming did not affect leaf membrane permeability (electrolyte leakage), active oxygen species (hydrogen peroxide and superoxide anion), activities of superoxide dismutase, peroxidase, ascorbate peroxidase and catalase, and malondialdehyde content in both species. Ascorbic acid and free proline contents in K. tibetica increased by 29.8% and 53.8%, respectively, but no change was found in K. pygmaea. In conclusion, K. pygmaea and K. tibetica could adapt under warmer temperature through keeping a steady antioxidative status.

Frost decreases content of sugars, ascorbic acid and some quercetin glycosides but stimulates selected carotenes in Rosa canina hips.

PubMed

Cunja, Vlasta; Mikulic-Petkovsek, Maja; Zupan, Anka; Stampar, Franci; Schmitzer, Valentina

2015-04-15

Primary and secondary metabolites of Rosa canina hips were determined by HPLC/MS during ripening and after frost damage. Rose hips were harvested six times from the beginning of September until the beginning of December. Color parameters a*, b* and L* decreased during maturation. Glucose and fructose were the predominant sugars representing up to 92% total sugars, and citric acid was the major organic acid detected in rose hips (constituting up to 58% total organic acids). Total sugar and ascorbic acid content significantly decreased after frost damage; from 42.2 to 25.9 g 100 g(-1) DW for sugars and from 716.8 to 176.0 mg 100 g(-1) DW for ascorbic acid. Conversely, β-carotene and lycopene levels increased in frostbitten rose hips to 22.1 and 113.2 mg 100 g(-1) DW, respectively. In addition to cyanidin-3-glucoside (highest level in hips was 125.7 μg 100 g (-1) DW), 45 different phenolic compounds have been identified. The most abundant were proanthocyanidins (their levels amounted up to 90% of total flavanol content) and their content showed no significant differences during maturation. The levels of catechin, phloridzin, flavanones and several quercetin glycosides were highest on the first three sampling dates and decreased after frost. Antioxidant capacity similarly decreased in frostbitten rose hips. Total phenolic content increased until the third sampling and decreased on later samplings. Copyright © 2015 Elsevier GmbH. All rights reserved.

Antioxidant Activity of Royal Jelly Hydrolysates Obtained by Enzymatic Treatment.

PubMed

Gu, Hyejung; Song, In-Bong; Han, Hye-Ju; Lee, Na-Young; Cha, Ji-Yun; Son, Yeon-Kyong; Kwon, Jungkee

2018-02-01

Recently, research on the processing of raw functional materials with the aim of improving various physiological activities has been conducted. In this study, we investigated the antioxidant activity of royal jelly (RJ) hydrolysates obtained from three commercial proteases. Enzyme-treated royal jelly (ERJ), in which the RJ hydrolysates were converted into easy-to-absorb shorter chain monomers through the removal of two known allergen proteins, showed no difference in the content of ( E )-10-hydroxydec-2-enoicacid (10-HDA) or the freshness parameter and showed a significant increase in total free amino acid content. The antioxidant activity of ERJ was determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and chemical assays. The ERJ showed about 80% DPPH-radical scavenging activity at same concentration of ascorbic acid. The antioxidant effect of ERJ was confirmed to be due to reduction of intracellular reactive oxidative species (ROS) and nitric oxide (NO) production in LPS-treated macrophages. Moreover, ERJ significantly increased the activity of the antioxidant enzyme superoxide dismutase (SOD) and the level of the antioxidant glutathione (GSH) in a dose-dependent manner. Interestingly, these antioxidant activities of ERJ were stronger than those of non-treated RJ. These findings indicate that ERJ has high potential as an antioxidant agent for use in human and animal diets.

Enteromorpha compressa Exhibits Potent Antioxidant Activity

PubMed Central

Shanab, Sanaa M. M.; Shalaby, Emad A.; El-Fayoumy, Eman A.

2011-01-01

The green macroalgae, Enteromorpha compressa (Linnaeus) Nees, Ulva lactuca, and E. linza, were seasonally collected from Abu Qir bay at Alexandria (Mediterranean Sea) This work aimed to investigate the seasonal environmental conditions, controlling the green algal growth, predominance, or disappearance and determining antioxidant activity. The freshly collected selected alga (E. compressa) was subjected to pigment analysis (chlorophyll and carotenoids) essential oil and antioxidant enzyme determination (ascorbate oxidase and catalase). The air-dried ground alga was extracted with ethanol (crude extract) then sequentially fractionated by organic solvents of increasing polarity (petroleum ether, chloroform, ethyl acetate, and water). Antioxidant activity of all extracts was assayed using different methods (total antioxidant, DPPH [2, 2 diphenyl-1-picrylhydrazyl], ABTS [2, 2 azino-bis ethylbenzthiazoline-6-sulfonic acid], and reducing power, and β-carotene linoleic acid bleaching methods). The results indicated that the antioxidant activity was concentration and time dependent. Ethyl acetate fraction demonstrated higher antioxidant activity against DPPH method (82.80%) compared to the synthetic standard butylated hydroxyl toluene (BHT, 88.5%). However, the crude ethanolic extract, pet ether, chloroform fractions recorded lower to moderate antioxidant activities (49.0, 66.0, and 78.0%, resp.). Using chromatographic and spectroscopic analyses, an active compound was separated and identified from the promising ethyl acetate fraction. PMID:21869863

Application of Ganghwa Mugwort in Combination with Ascorbic Acid for the Reduction of Residual Nitrite in Pork Sausage during Refrigerated Storage

PubMed Central

Hwang, Ko-Eun; Kim, Hyun-Wook; Song, Dong-Heon; Kim, Yong-Jae; Ham, Youn-Kyung; Lee, Choong-Hee; Choi, Yun-Sang; Kim, Cheon-Jei

2014-01-01

The application of ganghwa mugwort (GM), ascorbic acid (AC), and their combinations for reduction of residual nitrite contents was analyzed in pork sausages during storage of 28 d. Six treatments of pork sausages contained the following: Control (no antioxidant added), AC (0.05% AC), GM 0.1 (0.1% GM), GM 0.2 (0.2% GM), AC+GM 0.1 (0.05% AC + 0.1% GM) and AC+GM 0.2 (0.05% AC + 0.2% GM). Results showed that the mixture of 0.05% AC and 0.2% GM was most effective for reducing thiobarbituric acid reactive substances (TBARS) and residual nitrite contents than the control and GM added sausages alone (p<0.05). The color values of all treatments were significantly affected by adding GM (either alone or with AC). Additionally, the total color difference (ΔE) and hue angle (H°) values of treatments added with GM were higher than those of the control as the amount of GM increased (p<0.05). However, there were no significant differences in the pH values between the control and all treatments during the storage period (p>0.05). Our results showed possible applications of antioxidant combination, for preventing the lipid oxidation and decreasing the residual nitrite levels of meat products. PMID:26760936

Kinetic multi-layer model of the epithelial lining fluid (KM-ELF): Reactions of ozone and OH with antioxidants and surfactant molecules

NASA Astrophysics Data System (ADS)

Lakey, Pascale; Pöschl, Ulrich; Shiraiwa, Manabu

2015-04-01

Oxidants cause damage to biosurfaces such as the lung epithelium unless they are effectively scavenged. The respiratory tract is covered in a thin layer of fluid which extends from the nasal cavity to the alveoli and contain species that scavenge ozone and other incoming oxidants. The kinetic multi-layer model of the epithelial lining fluid (KM-ELF) has been developed in order to investigate the reactions of ozone and OH with antioxidants (ascorbate, uric acid, glutathione and α-tocopherol) and surfactant lipids and proteins within the epithelial lining fluid (ELF). The model incorporates different processes: gas phase diffusion, adsorption and desorption from the surface, bulk phase diffusion and known reactions at the surface and in the bulk. The ELF is split into many layers: a sorption layer, a surfactant layer, a near surface bulk layer and several bulk layers. Initial results using KM-ELF indicate that at ELF thicknesses of 80 nm and 1 × 10-4cm the ELF would become rapidly saturated with ozone with saturation occurring in less than a second. However, at an ELF thickness of 1 × 10-3cm concentration gradients were observed throughout the ELF and the presence of antioxidants reduced the O3 reaching the lung cells and tissues by 40% after 1 hour of exposure. In contrast, the antioxidants were efficient scavengers of OH radicals, although the large rate constants of OH reacting with the antioxidants resulted in the antioxidants decaying away rapidly. The chemical half-lives of the antioxidants and surface species were also calculated using KM-ELF as a function of O3 and OH concentration and ELF thickness. Finally, the pH dependence of the products of reactions between antioxidants and O3 were investigated. The KM-ELF model predicted that a harmful ascorbate ozonide product would increase from 1.4 × 1011cm-3at pH 7.4 to 1.1 × 1014 cm-3 at pH 4after 1 hour although a uric acid ozonide product would decrease from 2.0 × 1015cm-3to 5.9 × 1012cm-3.

Impacts of antioxidants on hydroxyl radical production from individual and mixed transition metals in a surrogate lung fluid

NASA Astrophysics Data System (ADS)

Charrier, Jessica G.; Anastasio, Cort

2011-12-01

Inhalation of ambient particulate matter causes morbidity and mortality in humans. One hypothesized mechanism of toxicity is the particle-induced formation of reactive oxygen species (ROS) - including the highly damaging hydroxyl radical ( rad OH) - followed by inflammation and a variety of diseases. While past studies have found correlations between ROS formation and a variety of metals, there are no quantitative measurements of rad OH formation from transition metals at concentrations relevant to 24-hour ambient particulate exposure. This research reports specific and quantitative measurements of rad OH formation from 10 individual transition metals (and several mixtures) in a cell-free surrogate lung fluid (SLF) with four antioxidants: ascorbate, citrate, glutathione, and uric acid. We find that Fe and Cu can produce rad OH under all antioxidant conditions as long as ascorbate is present and that mixtures of the two metals synergistically increase rad OH production. Manganese and vanadium can also produce rad OH under some conditions, but given that their ambient levels are typically very low, these metals are not likely to chemically produce significant levels of rad OH in the lung fluid. Cobalt, chromium, nickel, zinc, lead, and cadmium do not produce rad OH under any of our experimental conditions. The antioxidant composition of our SLF significantly affects rad OH production from Fe and Cu: ascorbate is required for rad OH formation, citrate increases rad OH production from Fe, and both citrate and glutathione suppress rad OH production from Cu. MINTEQ ligand speciation modeling indicates that citrate and glutathione affect rad OH production by changing metal speciation, altering the reactivity of the metals. In the most realistic SLF (i.e., with all four antioxidants), Fe generates approximately six times more rad OH than does the equivalent amount of Cu. Since levels of soluble Fe in PM are typically higher than those of Cu, our results suggest that Fe dominates the chemical generation of rad OH from deposited particles in the lungs.

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

PubMed

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

2010-11-01

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

Ascorbic acid deficiency leads to increased grain chalkiness in transgenic rice for suppressed of L-GalLDH.

PubMed

Yu, Le; Liu, Yonghai; Lu, Lina; Zhang, Qilei; Chen, Yezheng; Zhou, Liping; Chen, Hua; Peng, Changlian

2017-04-01

The grain chalkiness of rice (Oryza sativa L.), which determines the rice quality and price, is a major concern in rice breeding. Reactive oxygen species (ROS) plays a critical role in regulating rice endosperm chalkiness. Ascorbic acid (Asc) is a major plant antioxidant, which strictly regulates the levels of ROS. l-galactono-1, 4-lactone dehydrogenase (L-GalLDH, EC 1.3.2.3) is an enzyme that catalyzes the last step of Asc biosynthesis in higher plants. Here we show that the L-GalLDH-suppressed transgenic rice, GI-1 and GI-2, which have constitutively low (between 30% and 50%) leaf and grain Asc content compared with the wild-type (WT), exhibit significantly increased grain chalkiness. Further examination showed that the deficiency of Asc resulted in a higher lipid peroxidation and H 2 O 2 content, accompanied by a lower hydroxyl radical scavenging rate, total antioxidant capacity and photosynthetic ability. In addition, changes of the enzyme activities and gene transcript abundances related to starch synthesis were also observed in GI-1 and GI-2 grains. The results we presented here suggest a close correlation between Asc deficiency and grain chalkiness in the L-GalLDH-suppressed transgenics. Asc deficiency leads to the accumulation of H 2 O 2 , affecting antioxidant capacity and photosynthetic function, changing enzyme activities and gene transcript abundances related to starch synthesis, finally leading to the increased grain chalkiness. Copyright © 2017 Elsevier GmbH. All rights reserved.

Exogenous abscisic acid increases antioxidant enzymes and related gene expression in pepper (Capsicum annuum) leaves subjected to chilling stress.

PubMed

Guo, W L; Chen, R G; Gong, Z H; Yin, Y X; Ahmed, S S; He, Y M

2012-11-28

To elucidate how physiological and biochemical mechanisms of chilling stress are regulated by abscisic acid (ABA) pretreatment, pepper variety (cv. 'P70') seedlings were pretreated with 0.57 mM ABA for 72 h and then subjected to chilling stress at 10°/6°C (day/night). Chilling stress caused severe necrotic lesions on the leaves and increased malondialdehyde and H(2)O(2) levels. Activities of monodehydroascorbate reductase (DHAR), dehydroascorbate reductase, glutathione reductase, guaiacol peroxidase, ascorbate peroxidase, ascorbate, and glutathione increased due to chilling stress during the 72 h, while superoxide dismutase and catalase activities decreased during 24 h, suggesting that chilling stress activates the AsA-GSH cycle under catalase deactivation in pepper leaves. ABA pretreatment induced significant increases in the above-mentioned enzyme activities and progressive decreases in ascorbate and glutathione levels. On the other hand, ABA-pretreated seedlings under chilling stress increased superoxide dismutase and guaiacol peroxidase activities and lowered concentrations of other antioxidants compared with untreated chilling-stressed plants. These seedlings showed concomitant decreases in foliage damage symptoms, and levels of malondialdehyde and H(2)O(2). Induction of Mn-SOD and POD was observed in chilling-stressed plants treated with ABA. The expression of DHAR1 and DHAR2 was altered by chilling stress, but it was higher in the presence than in the absence of ABA at 24 h. Overall, the results indicate that exogenous application of ABA increases tolerance of plants to chilling-induced oxidative damage, mainly by enhancing superoxide dismutase and guaiacol peroxidase activities and related gene expression.

A New Alkenylmethylresorcinol from the Fruits of Ardisia kivuensis.

PubMed

Nguekeu, Yves M M; Ndontsa, Blanche L; Mbouangouere, Roukayatou; Awouafack, Maurice D; Ito, Takuya; Tane, Pierre; Morita, Hiroyuki

2016-05-01

The phytochemical study of the MeOH extract from the fruits of Ardisia kivuensis was carried out using repeated silica gel column chromatography followed by Sephadex LH-20 to afford a new alkenylmethylresorcinol, ardisinol III (1) along with three known compounds, oleanolic acid, β-sitosterol and pentacosanoic acid. The structure of 1 was elucidated using spectroscopic analysis (NMR and MS), and comparison with published data. Compound 1 had weak antioxidant activity (IC50 109.8 μg/mL) while other compounds were not active as compared to L-ascorbic acid (IC50 3.9 μg/mL).

Antioxidant Activity in the Extracts of Two Edible Aroids

PubMed Central

Mandal, P.; Misra, T. K.; Singh, I. D.

2010-01-01

Two neglected species of Araceae, Alocasia macrorhiza (Linn.) G. Don and Alocasia fornicata (Roxb.) Schott are important as food and ethno medicine in Asia and Africa. Their bioefficacy is documented in the Ayurveda. The solvent extracts of different edible parts of these two species like rhizomes, leaves, roots and stolons were screened for in vitro antioxidant properties using standard procedures. The successive extracts in hexane, benzene, toluene, chloroform, diethyl ether, ethyl acetate and water fraction exhibited IC50 values in the following order, roots>rhizome>leaves for Alocasia macrorhiza and leaves>stolon for Alocasia fornicate, respectively in 2,2-diphenyl-1-picryl hydrazyl antioxidant inhibition assay. Maximum antioxidant activity was observed in diethyl ether extracts for both species. The IC50 values were comparable with those of quercetine and ascorbic acid as standards. These results suggest that the two aroid species have antioxidant activity in their edible parts and should be extracted using diethyl ether solvent. PMID:20582198

A novel differential pulse voltammetric (DPV) method for measuring the antioxidant capacity of polyphenols-reducing cupric neocuproine complex.

PubMed

Tufan, Ayşe Nur; Baki, Sefa; Güçlü, Kubilay; Özyürek, Mustafa; Apak, Reşat

2014-07-23

A novel differential pulse voltammetric (DPV) method is presented, using a chromogenic oxidizing reagent, cupric neocuproine complex (Cu(Nc)2(2+)), for the assessment of antioxidant capacity of polyphenolic compounds (i.e., flavonoids, simple phenolic acids, and hydroxycinnamic acids), ascorbic acid, and real samples for the first time. The electrochemical behavior of the Cu(Nc)2(2+) complex was studied by cyclic voltammetry at a glassy carbon (GC) electrode. The electroanalytical method was based on the reduction of Cu(Nc)2(2+) to Cu(Nc)2(+) by antioxidants and electrochemical detection of the remaining Cu(II)-Nc (unreacted complex), the difference being correlated to antioxidant capacity of the analytes. The calibration curves of individual compounds comprising polyphenolics and vitamin C were constructed, and their response sensitivities and linear concentration ranges were determined. The reagent on the GC electrode retained its reactivity toward antioxidants, and the measured trolox equivalent antioxidant capacity (TEAC) values of various antioxidants suggested that the reactivity of the Cu(II)-Nc reagent is comparable to that of the solution-based spectrophotometric cupric ion reducing antioxidant capacity (CUPRAC) assay. This electroanalytical method better tolerated sample turbidity and provided higher sensitivity (i.e., lower detection limits) in antioxidant determination than the spectrophotometric assay. The proposed method was successfully applied to the measurement of total antioxidant capacity (TAC) in some herbal tea samples such as green tea, sage, marjoram, and alchemilla. Results demonstrated that the proposed voltammetric method has precision and accuracy comparable to those of the spectrophotometric CUPRAC assay.

Protein Oxidation and Sensory Quality of Brine-Injected Pork Loins Added Ascorbate or Extracts of Green Tea or Maté during Chill-Storage in High-Oxygen Modified Atmosphere.

PubMed

Jongberg, Sisse; Tørngren, Mari Ann; Skibsted, Leif H

2018-01-15

Background: Ascorbate is often applied to enhance stability and robustness of brine-injected pork chops sold for retail, but may affect protein oxidation, while plant extracts are potential substitutes. Methods: Brine-injected pork chops (weight-gain ~12%, NaCl ~0.9%) prepared with ascorbate (225 ppm), green tea extract (25 ppm gallic acid equivalents (GAE)), or maté extract (25 ppm GAE) stored (5 °C, seven days) in high-oxygen atmosphere packaging (MAP: 80% O₂ and 20% CO₂) were analyzed for color changes, sensory quality, and protein oxidation compared to a control without antioxidant. Results: No significant differences were observed for green tea and maté extracts as compared to ascorbate when evaluated based on lipid oxidation derived off-flavors, except for stale flavor, which maté significantly reduced. All treatments increased the level of the protein oxidation product, α-aminoadipic semialdehyde as compared to the control, and ascorbate was further found to increase thiol loss and protein cross-linking, with a concomitant decrease in the sensory perceived tenderness. Conclusions: Green tea and maté were found to equally protect against lipid oxidation derived off-flavors, and maté showed less prooxidative activity towards proteins as compared to ascorbate, resulting in more tender meat. Maté is a valuable substitute for ascorbate in brine-injected pork chops.

Irradiation Maintains Functional Components of Dry Hot Peppers (Capsicum annuum L.) under Ambient Storage

PubMed Central

Iqbal, Qumer; Amjad, Muhammad; Asi, Muhammad Rafique; Nawaz, Aamir; Khan, Samiya Mahmood; Ariño, Agustin; Ahmad, Tanveer

2016-01-01

Hot peppers used as natural flavoring and coloring agents are usually irradiated in prepacked form for decontamination. The effects of gamma radiation on the stability of functional components such as capsaicinoids and antioxidant compounds (carotenoids, ascorbic acid and total phenolics) were investigated in hot peppers (Capsicum annuum). Whole dried peppers packed in polyethylene bags were gamma irradiated at 0 (control), 2, 4, and 6 kGy and subsequently stored at 25 °C for 90 days. The irradiation dose did not substantially affect the initial contents of capsaicinoids, ascorbic acid and total phenolics, though the concentration of carotenoids declined by 8% from the control (76.9 mg/100 g) to 6 kGy radiation dose (70.7 mg/100 g). Similarly, during storage for 90 days at ambient temperature the concentrations of capsaicinoids and total phenolics remained fairly stable with mean percent reductions from 3.3% to 4.2%, while the levels of total carotenoids and ascorbic acid significantly (p < 0.05) declined by 12% and 14%, respectively. Overall, neither irradiation nor subsequent ambient storage could appreciably influence the contents of functional components in hot peppers. These results revealed that gamma irradiation up to 6 kGy can be safely used for decontamination to meet the needs for overseas markets without compromising product quality. PMID:28231158

Irradiation Maintains Functional Components of Dry Hot Peppers (Capsicum annuum L.) under Ambient Storage.

PubMed

Iqbal, Qumer; Amjad, Muhammad; Asi, Muhammad Rafique; Nawaz, Aamir; Khan, Samiya Mahmood; Ariño, Agustin; Ahmad, Tanveer

2016-09-12

Hot peppers used as natural flavoring and coloring agents are usually irradiated in prepacked form for decontamination. The effects of gamma radiation on the stability of functional components such as capsaicinoids and antioxidant compounds (carotenoids, ascorbic acid and total phenolics) were investigated in hot peppers ( Capsicum annuum ). Whole dried peppers packed in polyethylene bags were gamma irradiated at 0 (control), 2, 4, and 6 kGy and subsequently stored at 25 °C for 90 days. The irradiation dose did not substantially affect the initial contents of capsaicinoids, ascorbic acid and total phenolics, though the concentration of carotenoids declined by 8% from the control (76.9 mg/100 g) to 6 kGy radiation dose (70.7 mg/100 g). Similarly, during storage for 90 days at ambient temperature the concentrations of capsaicinoids and total phenolics remained fairly stable with mean percent reductions from 3.3% to 4.2%, while the levels of total carotenoids and ascorbic acid significantly ( p < 0.05) declined by 12% and 14%, respectively. Overall, neither irradiation nor subsequent ambient storage could appreciably influence the contents of functional components in hot peppers. These results revealed that gamma irradiation up to 6 kGy can be safely used for decontamination to meet the needs for overseas markets without compromising product quality.

Effect of ascorbic acid and dehydration on concentrations of total phenolics, antioxidant capacity, anthocyanins, and color in fruits.

PubMed

Rababah, Taha M; Ereifej, Khalil I; Howard, L

2005-06-01

The purpose of this investigation was to report on the total phenolics, anthocyanins, and oxygen radical absorbance capacity (ORAC) of strawberry, peach, and apple, the influence of dehydration and ascorbic acid treatments on the levels of these compounds, and the effect of these treatments on fruit color. Results showed that fresh strawberry had the highest levels for total phenolics [5317.9 mg of chlorogenic acid equivalents (CAE)/kg], whereas lower levels were found in fresh apple and peach (3392.1 and 1973.1 mg of CAE/kg, respectively), and for anthocyanins (138.8 mg/kg), whereas lower levels were found in fresh apple and peaches (11.0 and 18.9 mg/kg, respectively; fresh strawberry had an ORAC value of 62.9 mM/kg Trolox equivalents. The fresh apple and peach were found to have ORAC values of 14.7 and 11.4 mM/kg of Trolox equivalents, respectively. The color values indicated that the addition of 0.1% ascorbic acid increased the lightness (L) and decreased the redness (a) and yellowness (b) color values of fresh strawberry, peach, and apple, sliced samples, and the puree made from them. Also, results showed that dehydration is a good method to keep the concentrations of total phenolics and anthocyanins and ORAC values at high levels.

Validation of a high performance liquid chromatography method for the stabilization of epigallocatechin gallate.

PubMed

Fangueiro, Joana F; Parra, Alexander; Silva, Amélia M; Egea, Maria A; Souto, Eliana B; Garcia, Maria L; Calpena, Ana C

2014-11-20

Epigallocatechin gallate (EGCG) is a green tea catechin with potential health benefits, such as anti-oxidant, anti-carcinogenic and anti-inflammatory effects. In general, EGCG is highly susceptible to degradation, therefore presenting stability problems. The present paper was focused on the study of EGCG stability in HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid) medium regarding the pH dependency, storage temperature and in the presence of ascorbic acid a reducing agent. The evaluation of EGCG in HEPES buffer has demonstrated that this molecule is not able of maintaining its physicochemical properties and potential beneficial effects, since it is partially or completely degraded, depending on the EGCG concentration. The storage temperature of EGCG most suitable to maintain its structure was shown to be the lower values (4 or -20 °C). The pH 3.5 was able to provide greater stability than pH 7.4. However, the presence of a reducing agent (i.e., ascorbic acid) was shown to provide greater protection against degradation of EGCG. A validation method based on RP-HPLC with UV-vis detection was carried out for two media: water and a biocompatible physiological medium composed of Transcutol®P, ethanol and ascorbic acid. The quantification of EGCG for purposes, using pure EGCG, requires a validated HPLC method which could be possible to apply in pharmacokinetic and pharmacodynamics studies. Copyright © 2014. Published by Elsevier B.V.

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

NASA Astrophysics Data System (ADS)

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

2013-08-01

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

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

PubMed

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

2015-11-15

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

Evaluation of nutritional and antioxidant properties of the tropical fruits banana, litchi, mango, papaya, passion fruit and pineapple cultivated in Réunion French Island.

PubMed

Septembre-Malaterre, Axelle; Stanislas, Giovédie; Douraguia, Elisabeth; Gonthier, Marie-Paule

2016-12-01

Much attention is paid to the beneficial action of fruits against obesity-related oxidative stress. This study evaluated nutritional and antioxidant properties of banana, litchi, mango, papaya, passion fruit and pineapple from Réunion French Island. Results showed that total amounts of carbohydrates, vitamin C and carotenoids were 7.7-67.3g glucose equivalent, 4.7-84.9mg ascorbic acid equivalent and 26.6-3829.2μg β-carotene equivalent/100g fresh weight, respectively. Polyphenols were detected as the most abundant antioxidants (33.0-286.6mg gallic acid equivalent/100g fresh weight) with the highest content from passion fruit. UPLC-MS analysis led to identify epigallocatechin and quercetin derivatives from banana and litchi, ferulic, sinapic, syringic and gallic acids from pineapple and mango, and piceatannol from passion fruit. Polyphenol-rich extracts protected red blood cells and preadipose cells against oxidative stress. Altogether, these findings highlight nutritional benefits of French tropical fruits and their possible interest to improve antioxidant capacities of the body during obesity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characterization of antioxidant enzymes and peroxisomes of olive (Olea europaea L.) fruits.

PubMed

Lopez-Huertas, Eduardo; del Río, Luis A

2014-10-15

The presence of peroxisomes in olive (Olea europaea L.) fruits and different antioxidant enzymes occurring in this plant tissue is reported for the first time. Ultrastructural analysis showed that olive cells were characterized by the presence of large vacuoles and lipid drops. Plastids, mitochondria and peroxisomes were placed near the cell wall, showing some type of association with it. Olive fruit peroxisomes were purified by sucrose density-gradient centrifugation, and catalase, glutathione reductase and ascorbate peroxidase were found in peroxisomes. In olive fruit tissue the presence of a battery of antioxidant enzymes was demonstrated, including catalase, four superoxide dismutase isozymes (mainly an Fe-SOD plus 2 Cu,Zn-SOD and a Mn-SOD), all the enzymes of the ascorbate-glutathione cycle, reduced and oxidized glutathione, ascorbate, and four NADPH-recycling dehydrogenases. The knowledge of the full composition of antioxidants (enzymatic and non-enzymatic) in olive fruits is crucial to be able to understand the processes regulating the antioxidant composition of olive oil. Copyright © 2014 Elsevier GmbH. All rights reserved.

Optimization of antioxidant and antiglycated activities of polysaccharides from Arthrocnemum indicum leaves.

PubMed

Mzoughi, Zeineb; Chaouch, Mohamed Aymen; Hammi, Khaoula Mkadmini; Hafsa, Jawhar; Le Cerf, Didier; Ksouri, Riadh; Majdoub, Hatem

2018-07-01

Central composite design was performed to optimize uronic acid rate, esterification degree, total antioxidant ability and antiglycation capacity of carbohydrates from Arthrocnemum indicum leaves. Three independent variables were opted: extraction temperature, time and ratio (solvent/material). The optimal settings were: extraction temperature of 80°C, time of 288min and (solvent/solid) ratio of 40mL/g. Under these settings, uronic acid rate and esterification degree were 49.29%, 30.24%, respectively, whereas total antioxidant activity and antiglycation capacity was 35.81mg ascorbic acid equivalents/g matter and 69.81%, respectively. Colorimetric assays showed that total sugar and uronic acid contents for polysaccharide were 71.78% and 49.24%, respectively. Furthermore, Preliminary structure study was performed via various methods including FT-IR, NMR and UV-vis analysis. SEC analyzes revealed that polysaccharide had an average molecular weight of 2179kDa. Moreover, GC-MS analyzes showed that extracted polysaccharide was a pectic polysaccharide which formed of arabinose, mannose, galactose, rhamnose, glucose and xylose in the molar percentage of 66.68%, 3.93%, 12.71%, 6.31%, 6.08% and 4.29%, respectively. This results revealed that extracted polysaccharide can be employed as source of natural antioxidants and as possible antiglycated agents. Copyright © 2018 Elsevier B.V. All rights reserved.

Calibration of redox potential in sperm wash media and evaluation of oxidation-reduction potential values in various assisted reproductive technology culture media using MiOXSYS system.

PubMed

Panner Selvam, M K; Henkel, R; Sharma, R; Agarwal, A

2018-03-01

Oxidation-reduction potential describes the balance between the oxidants and antioxidants in fluids including semen. Various artificial culture media are used in andrology and IVF laboratories for sperm preparation and to support the development of fertilized oocytes under in vitro conditions. The composition and conditions of these media are vital for optimal functioning of the gametes. Currently, there are no data on the status of redox potential of sperm processing and assisted reproduction media. The purpose of this study was to compare the oxidation-reduction potential values of the different media and to calibrate the oxidation-reduction potential values of the sperm wash medium using oxidative stress inducer cumene hydroperoxide and antioxidant ascorbic acid. Redox potential was measured in 10 different media ranging from sperm wash media, freezing media and assisted reproductive technology one-step medium to sequential media. Oxidation-reduction potential values of the sequential culture medium and one-step culture medium were lower and significantly different (p < 0.05) from the sperm wash media. Calibration of the sperm wash media using the oxidant cumene hydroperoxide and antioxidant ascorbic acid demonstrated that oxidation-reduction potential and the concentration of oxidant or antioxidant are logarithmically dependent. This study highlights the importance of calibrating the oxidation-reduction potential levels of the sperm wash media in order to utilize it as a reference value to identify the physiological range of oxidation-reduction potential that does not have any adverse effect on normal physiological sperm function. © 2017 American Society of Andrology and European Academy of Andrology.

Effect of platelets on apparent leucocyte ascorbic acid content.

PubMed

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

1980-09-01

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

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

PubMed

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

2016-11-01

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

Effect on Tumor Necrosis Factor-α Production and Antioxidant Ability of Black Alder, as Factors Related to Its Anti-Inflammatory Properties

PubMed Central

Acero, Nuria

2012-01-01

Abstract Alders exhibit several uses in different areas and also offer some nutritional and medicinal values. The bark and leaves from black alder [Alnus glutinosa (L.) Gaertn] are used in folk medicine for the treatment of inflammatory processes and other health disorders. This study assessed if an extract of A. glutinosa stem bark exhibits some biological properties linked to improving the inflammatory state, which could partly justify its ethnopharmacological use. Therefore, various aspects of antioxidant activity as well as the effect on tumor necrosis factor-α (TNF-α) production were evaluated. The phytochemical study revealed the presence of terpenes, saponins, tannins, flavonoids, and anthraquinones (by high-performance thin-layer chromatography). The betulinic acid content in the extract, determined by reversed-phase high-performance liquid chromatography (validated method), was 0.72±0.027%. In addition, high amounts for total phenols as well as flavonoids were determined. The extract exhibited a 2,2′-diphenylpicrylhydrazyl radical scavenging capacity similar to that of ascorbic acid and had a significant effect on superoxide anion scavenging, superior to that of ascorbic acid. It was also able to protect HeLa cells from induced oxidative stress. In the TNF-α assay, levels of this citokine were depressed by the extract in HL-60 cells. To test the effect of the extract on cell proliferation, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed. According to the results, the antioxidant properties displayed by the extract of A. glutinosa stem bark, together with the effect on TNF-α levels, suggest that these activities, linked to a successful reduction in inflammatory processes, may support, in part, its ethnopharmacological use. PMID:22424456

Comparative assessment on in vitro antioxidant activities of ethanol extracts of Averrhoa bilimbi, Gymnema sylvestre and Capsicum frutescens.

PubMed

Rahman, Md Mominur; Habib, Md Razibul; Hasan, Md Anayet; Al Amin, Mohammad; Saha, Ayan; Mannan, Adnan

2014-01-01

Averrhoa bilimbi, Gymnema sylvestre and Capsicum frutescens are medicinal plants commonly used as traditional medicine for the treatment of various diseases. The present study was designed to investigate the antioxidant activities of Ethanolic extract of A. bilimbi, G. sylvestre and C. frutescens. The antioxidant activity of the extracts were evaluated using total phenolic and flavonoid contents, ferric reducing power and the free radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH). Total phenolic and flavonoid contents were higher in G. sylvestre (53.63636 ± 0.454545 mg/g gallic acid equivalent) and C. frutescens (26.66667 ± 2.081666 mg/g quercetin equivalent) respectively. Reducing power of the crude ethanol extracts increased with the concentrations of the extracts and all the extracts showed moderate free radical scavenging activity against DPPH. The plant extract displayed moderate phenolic and flavonoid contents compared to gallic acid and quercetin equivalent respectively, whereas also exhibited significant scavenging of DPPH radical and reducing power compared with ascorbic acid as standard. Our study suggests that G. sylvestre has significant antioxidant activity. The antioxidant compound of this plant might be a therapeutic candidate against oxidative stress related diseases. Different sub-fraction of A. bilimbi and C. frutescens should be studied further to assess the effect. Further study is necessary for isolation and characterization of the active antioxidant agents for better treatment.

Effects of molybdenum on water utilization, antioxidative defense system and osmotic-adjustment ability in winter wheat (Triticum aestivum) under drought stress.

PubMed

Wu, Songwei; Hu, Chengxiao; Tan, Qiling; Nie, Zhaojun; Sun, Xuecheng

2014-10-01

Molybdenum (Mo), as an essential trace element in plants, plays an essential role in abiotic stress tolerance of plants. To obtain a better understanding of drought tolerance enhanced by Mo, a hydroponic trial was conducted to investigate the effects of Mo on water utilization, antioxidant enzymes, non-enzymatic antioxidants, and osmotic-adjustment products in the Mo-efficient '97003' and Mo-inefficient '97014' under PEG simulated drought stress. Our results indicate that Mo application significantly enhanced Pn, chlorophyll, dry matter, grain yield, biomass, RWC and WUE and decreased Tr, Gs and water loss of wheat under drought stress, suggesting that Mo application improved the water utilization capacity in wheat. The activities of antioxidant enzymes such as superoxide dismutase, peroxidase, catalase, ascorbate peroxidase and the contents of non-enzymatic antioxidants content such as ascorbic acid, reduced glutathione, carotenoid were significantly increased and malonaldehyde contents were decreased by Mo application under PEG simulated drought stress, suggesting that Mo application enhanced the ability of scavenging active oxygen species. The osmotic-adjustment products such as soluble protein, proline and soluble sugar were also increased by Mo application under PEG simulated drought stress, indicating that Mo improved the osmotic adjustment ability in wheat. It is hypothesized that Mo application might improve the drought tolerance of wheat by enhancing water utilization capability and the abilities of antioxidative defense and osmotic adjustment. Similarities and differences between the Mo-efficient and Mo-inefficient cultivars wheat in response to Mo under drought stress are discussed. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

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

PubMed Central

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

2013-01-01

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

Investigation of the effect of biologically active threo-Ds-isocitric acid on oxidative stress in Paramecium caudatum.

PubMed

Morgunov, Igor G; Karpukhina, Olga V; Kamzolova, Svetlana V; Samoilenko, Vladimir A; Inozemtsev, Anatoly N

2018-01-02

The effect of biologically active form (threo-Ds-) of isocitric acid (ICA) on oxidative stress was studied using the infusorian Paramecium caudatum stressed by hydrogen peroxide and salts of some heavy metals (Cu, Pb, Zn, and Cd). ICA at concentrations between 0.5 and 10 mM favorably influenced the infusorian cells with oxidative stress induced by the toxicants studied. The maximal antioxidant effect of ICA was observed at its concentration 10 mM irrespective of the toxicant used (either H 2 O 2 or heavy metal ions). ICA was found to be a more active antioxidant than ascorbic acid. Biologically active pharmaceutically pure threo-Ds-ICA was produced through cultivation of the yeast Yarrowia lipolytica and isolated from the culture liquid in the form of crystalline monopotassium salt with a purity of 99.9%.

Antioxidant, antinociceptive and anti-inflammatory properties of the aqueous and ethanolic leaf extracts of Andrographis paniculata in some laboratory animals.

PubMed

Adedapo, Adeolu Alex; Adeoye, Bisi Olajumoke; Sofidiya, Margaret Oluwatoyin; Oyagbemi, Ademola Adetokunbo

2015-07-01

The study was designed to evaluate the anti-inflammatory, analgesic and antioxidant properties of Andrographis paniculata leaf extracts in laboratory animals. The dried and powdered leaves of the plant were subjected to phytochemical and proximate analyses. Its mineral content was also determined. Acute toxicity experiments were first performed to determine a safe dose level. The plant material was extracted using water and ethanol as solvents. These extracts were then used to test for the anti-inflammatory, analgesic and antioxidant properties of the plant. The anti-inflammatory tests included carrageenan-induced and histamine-induced paw oedema. The analgesic tests conducted were formalin paw lick test and acetic acid writhing test. The antioxidant activities of the extracts of A. paniculata were determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), total polyphenol (TP) and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) using ascorbic acid as standard for both DPPH and FRAP, and gallic acid as a standard for both TP and ABTS. The acute toxicity experiment demonstrated that the plant is safe at high doses even at 1600 mg/kg. It was observed that the ethanolic extract of A. paniculata had higher antioxidant activity than the aqueous extract. The experiments using both extracts may suggest that the extracts of A. paniculata leaves possess anti-inflammatory, analgesic and antioxidant properties, although the ethanolic extract seemed to have higher biological properties than the aqueous extract. The results from this study may have justified the plant's folkloric use for medicinal purpose.

Exogenous Glycine Nitrogen Enhances Accumulation of Glycosylated Flavonoids and Antioxidant Activity in Lettuce (Lactuca sativa L.).

PubMed

Yang, Xiao; Cui, Xiaoxian; Zhao, Li; Guo, Doudou; Feng, Lei; Wei, Shiwei; Zhao, Chao; Huang, Danfeng

2017-01-01

Glycine, the simplest amino acid in nature and one of the most abundant free amino acids in soil, is regarded as a model nutrient in organic nitrogen studies. To date, many studies have focused on the uptake, metabolism and distribution of organic nitrogen in plants, but few have investigated the nutritional performance of plants supplied with organic nitrogen. Lettuce ( Lactuca sativa L.), one of the most widely consumed leafy vegetables worldwide, is a significant source of antioxidants and bioactive compounds such as polyphenols, ascorbic acid and tocopherols. In this study, two lettuce cultivars, Shenxuan 1 and Lollo Rossa, were hydroponically cultured in media containing 4.5, 9, or 18 mM glycine or 9 mM nitrate (control) for 4 weeks, and the levels of health-promoting compounds and antioxidant activity of the lettuce leaf extracts were evaluated. Glycine significantly reduced fresh weight compared to control lettuce, while 9 mM glycine significantly increased fresh weight compared to 4.5 or 18 mM glycine. Compared to controls, glycine (18 mM for Shenxuan 1; 9 mM for Lollo Rossa) significantly increased the levels of most antioxidants (including total polyphenols, α-tocopherol) and antioxidant activity, suggesting appropriate glycine supply promotes antioxidant accumulation and activity. Glycine induced most glycosylated quercetin derivatives and luteolin derivatives detected and decreased some phenolic acids compared to nitrate treatment. This study indicates exogenous glycine supplementation could be used strategically to promote the accumulation of health-promoting compounds and antioxidant activity of hydroponically grown lettuce, which could potentially improve human nutrition.

Environmental effect of antioxidant additives on exhaust emission reduction in compression ignition engine fuelled with Annona methyl ester.

PubMed

Senthil, R; Silambarasan, R

2015-01-01

The aim of the present study is to analyse the effect of antioxidant l-ascorbic acid on engine performance and emissions of a diesel engine fuelled with methyl ester of Annona oil (MEAO). The antioxidant is mixed in various concentrations (100-400 mg) with MEAO. Result shows that the antioxidant additive mixture (MEAO+LA200) is effective in control of nitrogen oxides (NOx) and hydrocarbon (HC) emission of MEAO-fuelled engine without doing any engine modification. In this study by using MEAO, the NOx emission is reduced by about 23.38% at full load while compared with neat diesel fuel. Likewise there is a reduction in carbon monoxide, smoke, and HC by about 48%, 28.57% and 29.71% at full load condition compared with neat diesel fuel.

"Cut-off" effect of antioxidants and/or probes of variable lipophilicity in microheterogeneous media.

PubMed

Aliaga, Carolina; López de Arbina, Amaia; Rezende, Marcos Caroli

2016-09-01

The activities of two hydrophilic (ascorbic acid and Trolox) and two hydrophobic (α-tocopherol and BHT) antioxidants were measured by reaction with a series of 4-alkanoyloxyTEMPO radical probes 1 in buffered (pH 7), aqueous, micellar solutions of reduced Triton-X 100. In all cases, a cut-off effect was observed, in line with previous observations of the same effect for the partitioning of probe series 1 in this medium. These results support an interpretation of the cut-off effect in food emulsions, based on the "amphiphobic" nature of either the antioxidants or probes: competition between two molecular moieties, for the micellar hydrophobic core, tends to expose a reacting fragment differently to a more hydrophilic microenvironment, as the probe or antioxidant hydrophobicity increases. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impaired redox environment modulates cardiogenic and ion-channel gene expression in cardiac-resident and non-resident mesenchymal stem cells.

PubMed

Subramani, Baskar; Subbannagounder, Sellamuthu; Ramanathanpullai, Chithra; Palanivel, Sekar; Ramasamy, Rajesh

2017-03-01

Redox homeostasis plays a crucial role in the regulation of self-renewal and differentiation of stem cells. However, the behavioral actions of mesenchymal stem cells in redox imbalance state remain elusive. In the present study, the effect of redox imbalance that was induced by either hydrogen peroxide (H 2 O 2 ) or ascorbic acid on human cardiac-resident (hC-MSCs) and non-resident (umbilical cord) mesenchymal stem cells (hUC-MSCs) was evaluated. Both cells were sensitive and responsive when exposed to either H 2 O 2 or ascorbic acid at a concentration of 400 µmol/L. Ascorbic acid pre-treated cells remarkably ameliorated the reactive oxygen species level when treated with H 2 O 2 . The endogenous antioxidative enzyme gene (Sod1, Sod2, TRXR1 and Gpx1) expressions were escalated in both MSCs in response to reactive oxygen species elevation. In contrast, ascorbic acid pre-treated hUC-MSCs attenuated considerable anti-oxidative gene (TRXR1 and Gpx1) expressions, but not the hC-MSCs. Similarly, the cardiogenic gene (Nkx 2.5, Gata4, Mlc2a and β-MHC) and ion-channel gene ( I KDR , I KCa , I to and I Na.TTX ) expressions were significantly increased in both MSCs on the oxidative state. On the contrary, reduced environment could not alter the ion-channel gene expression and negatively regulated the cardiogenic gene expressions except for troponin-1 in both cells. In conclusion, redox imbalance potently alters the cardiac-resident and non-resident MSCs stemness, cardiogenic, and ion-channel gene expressions. In comparison with cardiac-resident MSC, non-resident umbilical cord-MSC has great potential to tolerate the redox imbalance and positively respond to cardiac regeneration. Impact statement Human mesenchymal stem cells (h-MSCs) are highly promising candidates for tissue repair in cardiovascular diseases. However, the retention of cells in the infarcted area has been a major challenge due to its poor viability and/or low survival rate after transplantation. The regenerative potential of mesenchymal stem cells (MSCs) repudiate and enter into premature senescence via oxidative stress. Thus, various strategies have been attempted to improve the MSC survival in 'toxic' conditions. Similarly, we investigated the response of cardiac resident MSC (hC-MSCs) and non-resident MSCs against the oxidative stress induced by H 2 O 2 . Supplementation of ascorbic acid (AA) into MSCs culture profoundly rescued the stem cells from oxidative stress induced by H 2 O 2 . Our data showed that the pre-treatment of AA is able to inhibit the cell death and thus preserving the viability and differentiation potential of MSCs.

Stomatal regulation, structural acclimation and metabolic shift towards defensive compounds reduce O3 load in birch under chronic O3 stress

NASA Astrophysics Data System (ADS)

Oksanen, E.; Riikonen, J.; Kontunen-Soppela, S.; Maenpaa, M.; Rousi, M.

2009-12-01

Northern forests are encountering new threats due to continuously increasing load of oxidative stress, e.g. due to rising tropospheric O3 levels, and simultaneous climate warming, which is more intense in northern latitudes as compared to global means. The proportion of silver birch (Betula pendula) in Finnish forests is expected to increase with climate warming. Unfortunately, we have growing evidence that the vitality and the carbon sink strength of birch trees are weakened under chronic O3 stress. In this study we investigated the effects of slightly elevated O3 concentration (1.3 x the ambient), temperature (T) and their combination on the antioxidant defense, gas exchange and leaf growth of Betula pendula saplings (clone 12) growing in open-field conditions over two growing seasons. The plants were measured for SLA (specific leaf area), total leaf area, net photosynthesis (Pn), stomatal conductance (gs), maximum rate of carboxylation (Vc,max), maximum rate of electron transport (Jmax), relative stomatal limitation to photosynthesis (ls), dark respiration (Rd), apoplastic concentrations of AA (ascorbic acid), DHA (dehydroascobate) and total ascorbate, the redox state of apoplastic ascorbate, and total antioxidant capacity. Elevated O3 enhanced the total antioxidant capacity in the apoplast in the first year of the experiment at the ambient T. However, during the second year of the experiment, the saplings responded to elevated O3 level by closing the stomata and by developing leaves with a lower leaf area per mass, rather than by accumulating ascorbate in the apoplast. O3 did not affect the total leaf area, whereas Pn was slightly and gs significantly reduced in the second year. Elevated T enhanced the total leaf area, Pn and Vc,max, redox state of ascorbate and total antioxidant capacity in the apoplast. The effects of T and O3 on total leaf area and net photosynthesis were counteractive. We were not able to detect significant differences in Rd between the treatments. Our results with birch suggest that (1) apoplastic AA plays only a minor and transient role in O3 defence whereas (2) stomatal regulation and structural plasticity of leaves are more important long-term mechanisms leading to O3 avoidance in chronic O3 stress with relatively low O3 concentrations. The role of antioxidant capacity was, however, modified by temperature in a complex manner. We should also remember that the clonal differences are wide in birch responses to O3 and therefore the role of AA in scavencing ROS in the apoplast maybe more important in other birch genotypes. Our previous studies with O3-stressed birches have indicated a considerable shift in leaf metabolome towards quercetin-phenolic compounds and chlorogenic acid, which have good radical-scavencing properties, and compounds related to leaf cuticular wax layer. Therefore we can conclude that the long-term protection of birch against chronic O3 stress in mainly composed of stomatal closure, secondary compounds and structural acclimation.

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

PubMed

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

2006-02-01

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

Effect of Xylopia aethiopica aqueous extract on antioxidant properties of refrigerated Roma tomato variety packaged in low density polyethylene bags.

PubMed

Babarinde, Grace Oluwakemi; Adegoke, Gabriel O

2015-03-01

Effects of Xylopia aethiopica (Dunal) A. Richard aqueous extract on the antioxidants of matured tomato fruits at red stage were investigated at 13 ± 2 °C and 80 ± 5 % relative humidity. A sample treated with sodium bicarbonate and untreated samples were included. Samples packaged in low density polyethylene (30 μm thickness) bags were analysed at intervals of 5 days. The treatments revealed statistically significant differences in ascorbic acid content of stored tomato fruits. Fruits treated with 5 % X. aethiopica on day 5 of storage had 21.0 mg/100 g which was significantly (p < 0.05) higher than 18.2 mg/100 g in untreated control samples. At 15th day of storage, ascorbic acid was 10.0 and 14.2 mg/100 g in tomato fruits treated with sodium bicarbonate and 5 % X. aethiopica respectively. The carotenoid and lycopene contents were lower in sodium bicarbonate-treated and the untreated control samples than in X. aethiopica-treated sample. The total phenolic contents were better retained in X. aethiopica-treated tomato than in control. Treatment of tomato fruits with X. aethiopica at 4 & 5 % levels significantly retained the qualities evaluated.

In Vitro Protective Effect of Phikud Navakot Extraction on Erythrocyte

PubMed Central

2016-01-01

Phikud Navakot (PN), Thai herbal remedy in National List of Essential Medicines, has been claimed to reduce many cardiovascular symptoms especially dizziness and fainting. Apart from blood supply, erythrocyte morphology, in both shape and size, is one of the main consideration factors in cardiovascular diseases and may be affected by vascular oxidative stress. However, little is known about antioxidative property of PN on erythrocyte to preserve red blood cell integrity. In this study, 1,000 μM hydrogen peroxide-induced oxidative stress was conducted on sheep erythrocyte. Three doses of PN (1, 0.5, and 0.25 mg/mL) and 10 μM of ascorbic acid were compared. The released hemoglobin absorbance was measured to demonstrate hemolysis. Electron microscopic and immunohistochemical studies were also performed to characterize dysmorphic erythrocyte and osmotic ability in relation to aquaporin- (AQP-) 1 expression, respectively. The results revealed that all doses of PN and ascorbic acid decreased the severity of dysmorphic erythrocyte, particularly echinocyte, acanthocyte, knizocyte, codocyte, clumping, and other malformations. However, the most effective was 0.5 mg/mL PN dosage. In addition, hydrostatic pressure may be increased in dysmorphic erythrocyte in association with AQP-1 upregulation. Our results demonstrated that PN composes antioxidative effect to maintain the integrity and osmotic ability on sheep erythrocyte. PMID:28003847

Antioxidants and Coronary Artery Disease: From Pathophysiology to Preventive Therapy

PubMed Central

Leopold, Jane A.

2014-01-01

Oxidant stress in the cardiovascular system may occur when antioxidant capacity is insufficient to reduce reactive oxygen species and other free radicals. Oxidant stress has been linked to the pathogenesis of atherosclerosis and incident coronary artery disease. As a result of this connection, early observational studies focused on dietary antioxidants, such as β-carotene, α-tocopherol, and ascorbic acid, and demonstrated an inverse relationship between intake of these antioxidants and major adverse cardiovascular events. These findings supported a number of randomized trials of selected antioxidants as primary and secondary prevention to decrease cardiac risk; however, many of these studies reported disappointing results with little or no observed risk reduction in antioxidant treated patients. Several plausible explanations for these findings have been suggested, including incorrect antioxidant choice or dose, synthetic versus dietary antioxidant as the intervention, and patient selection, all of which will be important to consider when designing future clinical trials. This review will focus on the contemporary evidence that is the basis for our current understanding of the role of antioxidants in cardiovascular disease prevention. PMID:25369999

Potentiation of antioxidant effect of dietary tender cluster beans (Cyamopsis tetragonoloba) by garlic (Allium sativum) in high-cholesterol-fed rats.

PubMed

Pande, Shubhra; Srinivasan, Krishnapura

2013-10-01

The antioxidant role of tender cluster beans (Cyamopsis tetragonoloba, CB), a rich source of soluble fibre, was investigated in a hypercholesterolemia-induced oxidative stress situation in rats. In the context of dietary garlic (Allium sativa) potentiating the hypocholesterolemic influence of CB, we also examined if dietary garlic enhances the antioxidant potential of CB. Groups of Wistar rats were rendered hypercholesterolemic by feeding them a 0.5% cholesterol diet for 8 weeks. Dietary interventions were made by inclusion of 15% tender CB powder or 1% garlic powder or their combination in a high-cholesterol diet. Concentrations of antioxidant molecules and activities of antioxidant enzymes in blood and liver were examined. Dietary CB displayed an antioxidant influence in terms of elevating ascorbic acid and glutathione concentrations and stimulating the activities of antioxidant enzymes both in blood and liver. The antioxidant effect of dietary CB was generally potentiated by co-administration of garlic. Thus, consumption of tender CB and garlic together could form a strategy for improving the body's antioxidant status.

Evaluation of Vitamin C for Adjuvant Sepsis Therapy

PubMed Central

2013-01-01

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

Morphological, physicochemical, and antioxidant profile of noncommercial banana cultivars

PubMed Central

Anyasi, Tonna A; Jideani, Afam IO; Mchau, Godwin A

2015-01-01

Banana cultivars––Luvhele (MusaABB), Mabonde (MusaAAA), and Muomva-red (Musa balbisiana) ––were characterized for morphological, physicochemical, and antioxidant properties. All three cultivars varied significantly (P < 0.05) in their morphology, pH, titratable acidity and total soluble solids with no significant difference in their ash content. Individual cultivars showed variations in flour starch granule when observed using a scanning electron microscope. Characterization of cultivars for total polyphenols (TPs) and antioxidant activity upon pretreatment with ascorbic, citric, and lactic acid shows that the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay of samples varied significantly as Muomva-red cultivar (1.02 ± 0.01 mg GA/g) expressed the highest DPPH activity at lactic acid concentration of 20 g/L. Total polyphenol content was also highest for Muomva-red [1091.76 ± 122.81 mg GAE/100 g (d.w.)]. The high amount of TPs present in these cultivars make them suitable source of bio-nutrients with great medicinal and health functions. PMID:25987997

Reducing Compounds Equivocally Influence Oxidation during Digestion of a High-Fat Beef Product, which Promotes Cytotoxicity in Colorectal Carcinoma Cell Lines.

PubMed

Van Hecke, Thomas; Wouters, An; Rombouts, Caroline; Izzati, Tazkiyah; Berardo, Alberto; Vossen, Els; Claeys, Erik; Van Camp, John; Raes, Katleen; Vanhaecke, Lynn; Peeters, Marc; De Vos, Winnok H; De Smet, Stefaan

2016-02-24

We studied the formation of malondialdehyde, 4-hydroxy-nonenal, and hexanal (lipid oxidation products, LOP) during in vitro digestion of a cooked low-fat and high-fat beef product in response to the addition of reducing compounds. We also investigated whether higher LOP in the digests resulted in a higher cyto- and genotoxicity in Caco-2, HT-29 and HCT-116 cell lines. High-fat compared to low-fat beef digests contained approximately 10-fold higher LOP concentrations (all P < 0.001), and induced higher cytotoxicity (P < 0.001). During digestion of the high-fat product, phenolic acids (gallic, ferulic, chlorogenic, and caffeic acid) displayed either pro-oxidant or antioxidant behavior at lower and higher doses respectively, whereas ascorbic acid was pro-oxidant at all doses, and the lipophilic reducing compounds (α-tocopherol, quercetin, and silibinin) all exerted a clear antioxidant effect. During digestion of the low-fat product, the hydrophilic compounds and quercetin were antioxidant. Decreases or increases in LOP concentrations amounted to 100% change versus controls.

Characterization of main primary and secondary metabolites and in vitro antioxidant and antihyperglycemic properties in the mesocarp of three biotypes of Pouteria lucuma.

PubMed

Fuentealba, Claudia; Gálvez, Lena; Cobos, Ariel; Olaeta, José Antonio; Defilippi, Bruno G; Chirinos, Rosana; Campos, David; Pedreschi, Romina

2016-01-01

Pouteria lucuma is an Andean fruit from pre-Incas' times highly appreciated due to its characteristic flavor and taste in its homeland. We characterized the primary (e.g., sugars and organic acids), and secondary (e.g., phenolics and carotenoids) and in vitro antioxidant and antihyperglycemic properties of Rosalia, Montero and Leiva 1 lucuma biotypes. Significant differences were found in these metabolites and functional properties related to biotype and ripeness stage. Results showed significant amounts of sugars (119.4-344 mg total sugars g(-1)DW) and organic acids (44.4-30.0 mg g(-1)DW) and functional associated compounds such as ascorbic acid (0.35-1.07 mg g(-1)DW), total phenolics (0.7-61.6 mg GAE g(-1)DW) and total carotenoids (0.22-0.50 mg β-carotene g(-1)DW). Important in vitro antioxidant and antihyperglycemic properties were found and provide the base for the standardization of lucuma harvest and postharvest focused not only on the enhancement of sensory but functional properties. Copyright © 2015 Elsevier Ltd. All rights reserved.

Function of antioxidant enzymes and metabolites during maturation of pea fruits.

PubMed

Matamoros, Manuel A; Loscos, Jorge; Dietz, Karl-Josef; Aparicio-Tejo, Pedro M; Becana, Manuel

2010-01-01

In plant cells, antioxidants keep reactive oxygen species at low concentrations, avoiding oxidative damage while allowing them to play crucial functions in signal transduction. However, little is known about the role of antioxidants during fruit maturation, especially in legumes. Snap pea (Pisum sativum) plants, which have edible fruits, were grown under nodulating and non-nodulating conditions. Fruits were classified in three maturity stages and antioxidants were determined in the seeds and seedless pods. Maturation or prolonged storage of fruits at 25 degrees C led to a decline in antioxidant activities and metabolites and in gamma-glutamylcysteine synthetase protein. Notable exceptions were superoxide dismutase activity and glutathione peroxidase protein, which increased in one or both of these processes. During maturation, cytosolic peroxiredoxin decreased in seeds but increased in pods, and ascorbate oxidase activity was largely reduced in seeds. In stored fruits, ascorbate oxidase activity was nearly abolished in seeds but doubled in pods. It is concluded that symbiotic nitrogen fixation is as effective as nitrogen fertilization in maintaining the antioxidant capacity of pea fruits and that, contrary to climacteric fruits, a general decrease in antioxidants during maturation does not involve oxidative stress. Results underscore the importance of the antioxidant system in reproductive organs and point to ascorbate-glutathione metabolism and cytosolic peroxiredoxin as key players in pea fruit development.

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

NASA Astrophysics Data System (ADS)

Sinkalu, Victor Olusegun; Ayo, Joseph Olusegun

2018-01-01

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

Total polyphenolic contents and in vitro antioxidant properties of eight Sida species from Western Ghats, India

PubMed Central

Subramanya, M. D.; Pai, Sandeep R.; Upadhya, Vinayak; Ankad, Gireesh M.; Bhagwat, Shalini S.; Hegde, Harsha V.

2015-01-01

Background: Sida L., is a medicinally important genus, the species of which are widely used in traditional systems of medicine in India. Pharmacologically, roots are known for anti-tumor, anti-HIV, hepatoprotective, and many other properties. Phenolic antioxidants help in reducing oxidative stress occurring during treatment of such diseases. Objective: The study aimed to evaluate and compare polyphenol contents and antioxidant properties of eight selected species of Sida from Western Ghats, India. Materials and Methods: Methanolic root extracts (10% w/v) of Sida species, viz., S. acuta, S. cordata, S. cordifolia, S. indica, S. mysorensis, S. retusa, S. rhombifolia, and S. spinosa were analyzed. Results: Sida cordifolia possessed highest total phenolic content (TPC: 1.92 ± 0.10 mg Caffeic Acid Equivalent/g and 2.13 ± 0.11 mg Tannic Acid Equivalant/g), total flavonoid content (TF: 2.60 ± 0.13 mg Quercetin Equivalent/g) and also possessed highest antioxidant activities in 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging (51.31 ± 2.57% Radical Scavenging Activity, (RSA); Trolox Equivalent Antioxidant Capacity: 566.25 ± 28.31μM; Ascorbic acid Equivalent Antioxidant Capacity: 477.80 ± 23.89 μM) and Ferric Reducing Antioxidant Power assays (TEAC: 590.67 ± 29.53 μM; AEAC: 600.67 ± 30.03 μM). Unlike DPPH and Ferric Reducing Antioxidant Power (FRAP) activity, 2, 2′-Azinobis (3-ethyl Benzo Thiazoline-6-Sulfonic acid) ABTS+ antioxidant activity was highest in S. indica (TEAC: 878.44 ± 43.92 μM; AEAC 968.44 ± 48.42 μM). It was significant to note that values of AEAC (μM) for all the antioxidant activities analyzed were higher than that of TEAC. Conclusion: The high contents of phenolic compounds in the root extracts of selected Sida species have direct correlation with their antioxidant properties. Conclusively, roots of S. cordifolia can be considered as the potential source of polyphenols and antioxidants. PMID:25878460

Total polyphenolic contents and in vitro antioxidant properties of eight Sida species from Western Ghats, India.

PubMed

Subramanya, M D; Pai, Sandeep R; Upadhya, Vinayak; Ankad, Gireesh M; Bhagwat, Shalini S; Hegde, Harsha V

2015-01-01

Sida L., is a medicinally important genus, the species of which are widely used in traditional systems of medicine in India. Pharmacologically, roots are known for anti-tumor, anti-HIV, hepatoprotective, and many other properties. Phenolic antioxidants help in reducing oxidative stress occurring during treatment of such diseases. The study aimed to evaluate and compare polyphenol contents and antioxidant properties of eight selected species of Sida from Western Ghats, India. Methanolic root extracts (10% w/v) of Sida species, viz., S. acuta, S. cordata, S. cordifolia, S. indica, S. mysorensis, S. retusa, S. rhombifolia, and S. spinosa were analyzed. Sida cordifolia possessed highest total phenolic content (TPC: 1.92 ± 0.10 mg Caffeic Acid Equivalent/g and 2.13 ± 0.11 mg Tannic Acid Equivalant/g), total flavonoid content (TF: 2.60 ± 0.13 mg Quercetin Equivalent/g) and also possessed highest antioxidant activities in 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging (51.31 ± 2.57% Radical Scavenging Activity, (RSA); Trolox Equivalent Antioxidant Capacity: 566.25 ± 28.31μM; Ascorbic acid Equivalent Antioxidant Capacity: 477.80 ± 23.89 μM) and Ferric Reducing Antioxidant Power assays (TEAC: 590.67 ± 29.53 μM; AEAC: 600.67 ± 30.03 μM). Unlike DPPH and Ferric Reducing Antioxidant Power (FRAP) activity, 2, 2'-Azinobis (3-ethyl Benzo Thiazoline-6-Sulfonic acid) ABTS(+) antioxidant activity was highest in S. indica (TEAC: 878.44 ± 43.92 μM; AEAC 968.44 ± 48.42 μM). It was significant to note that values of AEAC (μM) for all the antioxidant activities analyzed were higher than that of TEAC. The high contents of phenolic compounds in the root extracts of selected Sida species have direct correlation with their antioxidant properties. Conclusively, roots of S. cordifolia can be considered as the potential source of polyphenols and antioxidants.

Antioxidants in bakery products: a review.

PubMed

Nanditha, B; Prabhasankar, P

2009-01-01

Fats impart taste and texture to the product but it is susceptible to oxidation leading to the development of rancidity and off-flavor. Since ancient times it has been in practice to use antioxidants in foods. Discovery of synthetic antioxidants has revolutionized the use of antioxidants in food. The effect of these antioxidants in bakery products were reviewed and found to be effective in enhancing the shelf life. Animal experimental studies have shown that some of the synthetic antioxidants had toxigenic, mutagenic, and carcinogenic effects. Hence there is an increasing demand for the use of natural antioxidants in foods, especially in bakery products. Some of the natural antioxidants such as alpha-tocopherol, beta-carotene, and ascorbic acid were already used in bakery products. These natural antioxidants are found to be effective in enhancing the shelf life of bakery products but not to the extent of synthetic antioxidants. Baking processing steps may lower the antioxidative activity but techniques such as encapsulation of antioxidants can retain their activity. Antioxidative activity of the plant extracts such as garcinia, curcumin, vanillins, and mint were reviewed but studies on their role in bakery products were limited or very few. Hence there is a wide scope for study under this direction in depth.

Effect of sodium ascorbate dose on the shelf life stability of reduced nitrite liver pâtés.

PubMed

Vossen, Els; Doolaege, Evelyne H A; Moges, Haile Demewez; De Meulenaer, Bruno; Szczepaniak, Slawomir; Raes, Katleen; De Smet, Stefaan

2012-05-01

The effect of sodium ascorbate (SA; 500, 750, 1000 mg/kg) and sodium nitrite (SN; 40, 80, 120 mg/kg) doses on the shelf-life stability of liver pâtés was investigated in a full factorial design. Clear dose-dependent responses of the added SN or SA were found for the concentrations of nitrite, ascorbic acid and dehydroascorbic acid in the raw batters and in the cooked pâtés before and after 48 h of chilled display. Decreasing the SN dose to 80 mg/kg had no negative impact on the colour stability (a* value) and lipid oxidation (TBARS), and no additional antioxidant effect of SA was noticed. Lowering SN to 40 mg/kg resulted in proper colour formation, but the colour stability was inferior and lipid oxidation increased. Yet, increasing the amount of SA, at this low SN dose, resulted in lower TBARS values. Decreasing the SN dose to 80 or 40 mg/kg had no distinct effect on protein oxidation, which was however only measured by carbonyl content. Copyright © 2011 Elsevier Ltd. All rights reserved.

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

PubMed

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

2015-12-01

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

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

PubMed

Sarker, Umakanta; Oba, Shinya

2018-06-30

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

Preliminary study of the antioxidant properties of flowers and roots of Pyrostegia venusta (Ker Gawl) Miers.

PubMed

Roy, Purabi; Amdekar, Sarika; Kumar, Avnish; Singh, Vinod

2011-08-23

Free radical stress leads to tissue injury and can eventually to arthritis, atherosclerosis, diabetes mellitus, neurodegenerative diseases and carcinogenesis. Several studies are ongoing worldwide to find natural antioxidants of plant origin. We assessed the in-vitro antioxidant activities and screened the phytochemical constituents of methanolic extracts of Pyrostegia venusta (Ker Gawl) Miers. We evaluated the antioxidant potential and phytochemical constituents of P. venusta using 1,1-Diphenyl-2-picrylhydrazyl (DPPH), 2, 2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and ferric reducing antioxidant power (FRAP) assays. Gas chromatography-mass spectroscopy (GC-MS) studies were also undertaken to assess the phytochemical composition of the flower extracts. Phytochemical analyses revealed the presence of terpenoids, alkaloids, tannins, steroids, and saponins. The reducing ability of both extracts was in the range (in μm Fe(II)/g) of 112.49-3046.98 compared with butylated hydroxytoluene (BHT; 63.56 ± 2.62), catechin (972.02 ± 0.72 μm) and quercetin 3208.27 ± 31.29. A significant inhibitory effect of extracts of flowers (IC50 = 0.018 ± 0.69 mg/ml) and roots (IC50 = 0.026 ± 0.94 mg/ml) on ABTS free radicals was detected. The antioxidant activity of the extracts of flowers (95%) and roots (94%) on DPPH radicals was comparable with that of ascorbic acid (98.9%) and BHT (97.6%). GC-MS study revealed the presence of myoinositol, hexadecanoic acid, linoleic acid, palmitic acid and oleic acid in the flower extracts. These data suggest that P. venusta is a natural source of antioxidants. The extracts of flowers and roots of P. venusta contain significant amounts of phytochemicals with antioxidative properties and could serve as inhibitors or scavengers of free radicals. P. venusta could be exploited as a potential source for plant-based pharmaceutical products. These results could form a sound basis for further investigation in the potential discovery of new natural bioactive compounds.

Determination of mineral constituents, phytochemicals and antioxidant qualities of Cleome gynandra, compared to Brassica oleracea and Beta vulgaris

NASA Astrophysics Data System (ADS)

Moyo, Mack; Amoo, Stephen O.; Aremu, Adeyemi O.; Gruz, Jiri; Šubrtová, Michaela; Jarošová, Monika; Tarkowski, Petr; Doležal, Karel

2017-12-01

The study compared mineral, chemical and antioxidant qualities of Cleome gynandra, a wild leafy vegetable, with two widely consumed commercial vegetables; Brassica oleracea and Beta vulgaris. Mineral nutrients were quantified with inductively coupled plasma mass spectrometry (ICP-MS), phenolic compounds using ultra-high performance liquid chromatography coupled to a mass spectrometer (UHPLC-MS) and β-carotene and vitamin C using high performance liquid chromatography with a photodiode array detector (HPLC-PDA). The antioxidant potential was evaluated using 2,2–diphenyl–1–picryl hydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC). Cleome gynandra had highest concentrations of phosphorus, potassium, calcium, iron, zinc, ascorbic acid, total phenolics and flavonoids; whereas sodium, magnesium, manganese, copper and β-carotene were higher in Beta vulgaris. The significantly higher antioxidant activity (P ≤ 0.05) exhibited by Cleome gynandra in comparison to the two commercial vegetables may be due to its significantly high levels of vitamin C and phenolic acids. These findings on the mineral, chemical and antioxidant properties of Cleome gynandra provide compelling scientific evidence of its potential in adding diversity to our diet and contributing towards the daily nutritional requirements of millions of people for food and nutritional security.

Bioactive compounds and antioxidant activity of fresh and processed white cauliflower.

PubMed

Ahmed, Fouad A; Ali, Rehab F M

2013-01-01

Brassica species are very rich in health-promoting phytochemicals, including phenolic compounds, vitamin C, and minerals. The objective of this study was to investigate the effect of different blanching (i.e., water and steam) and cooking (i.e., water boiling, steam boiling, microwaving, and stir-frying) methods on the nutrient components, phytochemical contents (i.e., polyphenols, carotenoids, flavonoid, and ascorbic acid), antioxidant activity measured by DPPH assay, and phenolic profiles of white cauliflower. Results showed that water boiling and water blanching processes had a great effect on the nutrient components and caused significant losses of dry matter, protein, and mineral and phytochemical contents. However, steam treatments (blanching and cooking), stir-frying, and microwaving presented the lowest reductions. Methanolic extract of fresh cauliflower had significantly the highest antioxidant activity (68.91%) followed by the extracts of steam-blanched, steam-boiled, stir-fried, and microwaved cauliflower 61.83%, 59.15%, 58.93%, and 58.24%, respectively. HPLC analysis revealed that the predominant phenolics of raw cauliflower were protocatechuic acid (192.45), quercetin (202.4), pyrogallol (18.9), vanillic acid (11.90), coumaric acid (6.94), and kaempferol (25.91) mg/100 g DW, respectively.

Bioactive Compounds and Antioxidant Activity of Fresh and Processed White Cauliflower

PubMed Central

Ahmed, Fouad A.; Ali, Rehab F. M.

2013-01-01

Brassica species are very rich in health-promoting phytochemicals, including phenolic compounds, vitamin C, and minerals. The objective of this study was to investigate the effect of different blanching (i.e., water and steam) and cooking (i.e., water boiling, steam boiling, microwaving, and stir-frying) methods on the nutrient components, phytochemical contents (i.e., polyphenols, carotenoids, flavonoid, and ascorbic acid), antioxidant activity measured by DPPH assay, and phenolic profiles of white cauliflower. Results showed that water boiling and water blanching processes had a great effect on the nutrient components and caused significant losses of dry matter, protein, and mineral and phytochemical contents. However, steam treatments (blanching and cooking), stir-frying, and microwaving presented the lowest reductions. Methanolic extract of fresh cauliflower had significantly the highest antioxidant activity (68.91%) followed by the extracts of steam-blanched, steam-boiled, stir-fried, and microwaved cauliflower 61.83%, 59.15%, 58.93%, and 58.24%, respectively. HPLC analysis revealed that the predominant phenolics of raw cauliflower were protocatechuic acid (192.45), quercetin (202.4), pyrogallol (18.9), vanillic acid (11.90), coumaric acid (6.94), and kaempferol (25.91) mg/100 g DW, respectively. PMID:24171164

Sonication improves kasturi lime (Citrus microcarpa) juice quality.

PubMed

Bhat, Rajeev; Kamaruddin, Nor Shuaidda Bt Che; Min-Tze, Liong; Karim, A A

2011-11-01

Freshly squeezed kasturi lime fruit juice was sonicated (for 0, 30 and 60min at 20°C, 25kHz frequency) to evaluate its impact on selected physico-chemical and antioxidant properties, such as pH, °Brix, titratable acidity, Hunter color values (L(∗), a(∗), b(∗)), ascorbic acid, DPPH radical scavenging activity, total phenolics, antioxidant capacity, flavonoids and flavonols. Additionally, the effect of sonication treatments on the microbial load (TPC, yeast and mold) were also evaluated. Sonication of juice samples for 60min showed enhancement in most of the bioactive compounds compared to samples treated for 30min and control samples (untreated). Significant reductions in the microbial load corresponding to sonication time were also recorded. Results of the present study indicate that sonication may be employed as a suitable technique for kasturi lime juice processing, where antioxidant and other bioactive compound retention or enhancement is desired, along with the achievement of safety and quality standards. Copyright © 2011 Elsevier B.V. All rights reserved.

Phytochemicals and antioxidant capacity in four Italian traditional maize (Zea mays L.) varieties.

PubMed

Capocchi, Antonella; Bottega, Stefania; Spanò, Carmelina; Fontanini, Debora

2017-08-01

Flours of four pigmented (from orange to red and dark red) local Italian corns, studied for their soluble, soluble conjugate, and insoluble-bound phenols and flavonoids, showed a prevalence of the insoluble-bound fraction (70-80%). Correlations were found between the flours antioxidant capacity, measured with CUPRAC, FRAP, and DPPH methods, and soluble phenols and flavonoids content. A correlation was also found between ascorbic acid content and flours antioxidant power. Anthocyanins were present in small amounts in the red/dark red seeds; however, acid-alcohol assays and spectral analyses of pericarp extracts indicated the presence of red-brick phlobaphenes in these varieties. Spectrophotometrically quantified total carotenoids were significantly higher in one of the local varieties (Nano); RP-HPLC analyses indicated that the local varieties contained significantly higher amounts of zeaxanthin and β-carotene, and lower amounts of lutein, than a commercial line. Among local varieties, Nano expressed the highest levels of zeaxanthin, β-carotene, and β-cryptoxanthin.

Bioactivity of essential oil from lemongrass (Cymbopogon citratus Stapf) as antioxidant agent

NASA Astrophysics Data System (ADS)

Anggraeni, Nenden Indrayati; Hidayat, Ika Wiani; Rachman, Saadah Diana; Ersanda

2018-02-01

Free radical induced oxidative stress that influences the occurrence of various degenerative diseases such as cancer, coronary heart disease and premature aging. In the case that body's antioxidant defense system does not have excessive antioxidants, additional natural antioxidant via food or other nutrients intake is needed. Stems of lemongrass Cymbopogon citratus Stapf are known to contain phenolic compounds that are known to have antioxidant activity. Lemongrass (Cymbopogon citratus Stapf) plant is well known herb in Asia, espesially in Indonesia and used for cooking and has many health benefits. A study has been carried out to determine antioxidant potential of stems of lemongrass. In this the primary study is to examine essential oil Cymbopogon citratus Stapf from Cileles Jatinangor as an antioxidant agent. Essential oil of Cymbopogon citratus Stapf was isolated from 1272 g of dried stem by using Karlsruhe steam distillation methods with 0.24% in yield. The product of essential oil was also tested against antioxidant activity DPPH and resulted low activity compare to ascorbic acid and lemongrass oil standard as reference material.

Effect of proline on biochemical and molecular mechanisms in lettuce (Lactuca sativa L.) exposed to UV-B radiation.

PubMed

Aksakal, Ozkan; Tabay, Dilruba; Esringu, Aslıhan; Icoglu Aksakal, Feyza; Esim, Nevzat

2017-02-15

The purpose of the present study was to evaluate the role of proline (Pro) in relieving UV-B radiation-induced oxidative stress in lettuce. Lettuce seedlings were exposed to 3.3 W m -2 UV-B radiation for 12 h after pre-treatment sprayed with 20 mM Pro. The data for malondialdehyde (MDA), hydrogen peroxide (H 2 O 2 ), endogenous Pro level, the activities of antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD)], total phenolic concentration, antioxidant capacity, expression of phenylalanine ammonia lyase (PAL), γ-tocopherol methyltransferase (γ-TMT) and proline dehydrogenase (ProDH) genes, phytohormone levels such as abscisic acid (ABA), gibberellic acid (GA), indole acetic acid (IAA) and salicylic acid (SA), soluble sugars and organic acids were recorded. It was found that Pro alleviated the oxidative damage in the seedlings of lettuce as demonstrated by lower lipid peroxidation and H 2 O 2 content, increasing the endogenous Pro level, the activity of antioxidant enzymes, total phenolic concentration and the antioxidant capacity. Additionally, it was revealed that exogenous application of Pro enhanced the levels of GA, IAA, the concentrations of soluble sugars and organic acids and expressions of PAL, γ-TMT and ProDH genes as compared to the control. The results obtained in this study suggest that pre-treatment with exogenous Pro provides important contributions to the increase in the UV-B tolerance of lettuce by regulating the biochemical mechanisms of UV-B response.

Age-related changes in the kinetics of human lenses: prevention of the cataract

PubMed Central

Pescosolido, Nicola; Barbato, Andrea; Giannotti, Rossella; Komaiha, Chiara; Lenarduzzi, Fiammetta

2016-01-01

The crystalline lens is a transparent, biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina and, by changing shape, it adjusts focal distance (accommodation). The three classes of structural proteins found in the lens are α, β, and γ crystallins. These proteins make up more than 90% of the total dry mass of the eye lens. Other components which can be found are sugars, lipids, water, several antioxidants and low weight molecules. When ageing changes occur in the lens, it causes a gradual reduction in transparency, presbyopia and an increase in the scattering and aberration of light waves as well as a degradation of the optical quality of the eye. The main changes that occur with aging are: 1) reduced diffusion of water from the outside to the inside of the lens and from its cortical to its nuclear zone; 2) crystalline change due to the accumulation of high molecular weight aggregates and insoluble proteins; 3) production of advanced glycation end products (AGEs), lipid accumulation, reduction of reduced glutathione content and destruction of ascorbic acid. Even if effective strategies in preventing cataract onset are not already known, good results have been reached in some cases with oral administration of antioxidant substances such as caffeine, pyruvic acid, epigallocatechin gallate (EGCG), α-lipoic acid and ascorbic acid. Furthermore, methionine sulfoxide reductase A (MSRA) over expression could protect lens cells both in presence and in absence of oxidative stress-induced damage. Nevertheless, promising results have been obtained by reducing ultraviolet-induced oxidative damage. PMID:27803872

Screening of antimicrobial, antioxidant properties and bioactive compounds of some edible mushrooms cultivated in Bangladesh.

PubMed

Chowdhury, Mohammed; Kubra, Khadizatul; Ahmed, Sheikh

2015-02-07

For a long time mushrooms have been playing an important role in several aspects of the human activity. Recently edible mushrooms are used extensively in cooking and make part of new food in Bangladesh for their beneficial properties. The aim of this study is to screen some values of mushrooms used in Bangladesh. Methanolic extracts of 3 edible mushrooms (Pleurotus ostreatus, Lentinula edodes, Hypsizigus tessulatus) isolated from Chittagong, Bangladesh were used in this study. Phenolic compounds in the mushroom methanolic extracts were estimated by a colorimetric assay. The antioxidant activity was determined by radical 1, 1-diphenyl;-2-picrylhydrazyl (DPPH) radical scavenging assay. Eight microbial isolates were used for antimicrobial activity of methanolic extract of mushrooms by the agar well diffusion method with slight modification. Determination of antimicrobial activity indicated considerable activity against all bacteria and fungi reveling zone of inhibition ranged from 7 ± 0.2 to 20 ± 0.1 mm. Minimum inhibitory concentration values of the extracts showed that they are also active even in least concentrations ranged from 1 mg/ml to 9 mg/ml. Lentinula edodes showed the best antimicrobial activity than others. Pseudomonas aeruginosa was quite resistant and Saccharomyces cerevisiae was more sensitive than others microbial isolates. Antioxidant efficiency by inhibitory concentration on 1,1-Diphenly-2-picrylhydrazyl (DPPH) was found significant when compared to standard antioxidant like ascorbic Acid . The concentration (IC50) ranged from 100 ± 1.20 to 110 ± 1.24 μg/ml. Total phenols are the major bioactive component found in extracts of isolates expressed as mg of GAE per gram of fruit body, which ranged from 3.20 ± 0.05 to 10.66 ± 0.52 mg/ml. Average concentration of flavonoid ranged from 2.50 ± 0.008 mg/ml to 4.76 ± 0.11 mg/ml; followed by very small concentration of ascorbic acid (range, 0.06 ± 0.00 mg/ml to 0.21 ± 0.01 mg/ml) in all the isolates. All the isolates showed high phenol and flavonoid content (except Pleurotus ostreatus), but ascorbic acid content was found in traces. This study has revealed that selected edible mushrooms have not only nutritional values but also some therapeutic values. Proper and more investigations can lead us to use these as strong medicine in future.

Total antioxidant/oxidant status in meningism and meningitis.

PubMed

Aycicek, Ali; Iscan, Akin; Erel, Ozcan; Akcali, Mustafa; Selek, Sahbettin

2006-12-01

The objective of this study was to investigate the antioxidant/oxidant status of serum and cerebrospinal fluid in children with meningismus and acute bacterial meningitis. Twenty-three children (age range, 0.75 to 9 years) with fever and meningeal signs that required analysis of the cerebrospinal fluid, but no cytologic or biochemical evidence of meningitis in their serum and cerebrospinal fluid, constituted the meningismus group. Thirty-one children (age range, 0.5 to 10 years) with acute bacterial meningitis constituted the meningitis group. Twenty-nine healthy children (age range, 0.5 to 11 years) were recruited as control subjects. Antioxidant status (ascorbic acid, albumin, thiol, uric acid, total bilirubin, total antioxidant capacity, catalase and ceruloplasmin concentrations) and oxidant status (lipid hydroperoxide and total oxidant status) were measured. The serum antioxidant status was lower, and oxidant status levels higher in both meningitis and meningismus subjects than in the control children (P < 0.001). Cerebrospinal fluid oxidant status was lower in the meningitis group than in the meningismus group (P < 0.05). These results indicate that serum antioxidant status was lower, and serum oxidant status was higher in children in the meningismus and meningitis groups, whereas cerebrospinal fluid oxidant status was higher in the meningismus group than in the meningitis group.

Salicylic acid improves root antioxidant defense system and total antioxidant capacities of flax subjected to cadmium.

PubMed

Belkadhi, Aïcha; De Haro, Antonio; Soengas, Pilar; Obregon, Sara; Cartea, Maria Elena; Djebali, Wahbi; Chaïbi, Wided

2013-07-01

Cadmium (Cd) disrupts the normal growth and development of plants, depending on their tolerance to this toxic element. The present study was focused on the impacts of exogenous salicylic acid (SA) on the response and regulation of the antioxidant defense system and membrane lipids to 16-day-old flax plantlets under Cd stress. Exposure of flax to high Cd concentrations led to strong inhibition of root growth and enhanced lipid peroxides, membrane permeability, protein oxidation, and hydrogen peroxide (H2O2) production to varying degrees. Concomitantly, activities of the antioxidant enzymes catalase (CAT, EC 1.11.1.6), guaïcol peroxydase (GPX, EC 1.11.1.7), ascorbate peroxydase (APX, EC 1.11.1.11), and superoxide dismutase (SOD, EC 1.15.1.1), and the total antioxidant capacities (2,2'-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and ferric reducing antioxidant power (FRAP)) were significantly altered by Cd. In contrast, exogenous SA greatly reduced the toxic effects of Cd on the root growth, antioxidant system, and membrane lipid content. The Cd-treated plantlets pre-soaked with SA exhibited less lipid and protein oxidation and membrane alteration, as well as a high level of total antioxidant capacities and increased activities of antioxidant enzymes except of CAT. These results may suggest that SA plays an important role in triggering the root antioxidant system, thereby preventing membrane damage as well as the denaturation of its components.

Protein Oxidation and Sensory Quality of Brine-Injected Pork Loins Added Ascorbate or Extracts of Green Tea or Maté during Chill-Storage in High-Oxygen Modified Atmosphere

PubMed Central

Tørngren, Mari Ann

2018-01-01

Background: Ascorbate is often applied to enhance stability and robustness of brine-injected pork chops sold for retail, but may affect protein oxidation, while plant extracts are potential substitutes. Methods: Brine-injected pork chops (weight-gain ~12%, NaCl ~0.9%) prepared with ascorbate (225 ppm), green tea extract (25 ppm gallic acid equivalents (GAE)), or maté extract (25 ppm GAE) stored (5 °C, seven days) in high-oxygen atmosphere packaging (MAP: 80% O2 and 20% CO2) were analyzed for color changes, sensory quality, and protein oxidation compared to a control without antioxidant. Results: No significant differences were observed for green tea and maté extracts as compared to ascorbate when evaluated based on lipid oxidation derived off-flavors, except for stale flavor, which maté significantly reduced. All treatments increased the level of the protein oxidation product, α-aminoadipic semialdehyde as compared to the control, and ascorbate was further found to increase thiol loss and protein cross-linking, with a concomitant decrease in the sensory perceived tenderness. Conclusions: Green tea and maté were found to equally protect against lipid oxidation derived off-flavors, and maté showed less prooxidative activity towards proteins as compared to ascorbate, resulting in more tender meat. Maté is a valuable substitute for ascorbate in brine-injected pork chops. PMID:29342928