ESR study on free radicals trapped in crosslinked polytetrafluoroethylene (PTFE)

International Nuclear Information System (INIS)

Oshima, Akihiro; Tabata, Yoneho; Seguchi, Tadao

1997-01-01

Free radicals in crosslinked PTFE which formed by 60 Co γ-rays irradiation at 77 K and at room temperature were studied by electron spin resonance (ESR) spectroscopy. The crosslinked PTFE specimens with different crosslinking density were prepared by electron beam irradiation in the molten state. The ESR spectra observed in the irradiated crosslinked PTFE are much different from those in non-crosslinked PTFE (virgin); a broad singlet component increases with increasing the crosslinking density, G-value of radicals is much higher in crosslinked PTFE than in non-crosslinked one. Free radicals related to the broad component are trapped in the non-crystalline region of crosslinked PTFE and rather stable at room temperature, whereas radicals trapped in amorphous non-crosslinked PTFE are unstable at room temperature. It is thought that most of free radicals trapped in the crosslinked PTFE are formed in the crosslinked amorphous region. The trapped radicals decays around 383 K (110 o C) due to the molecular motion of α-relaxation. (Author)

EPR spin trapping of protein radicals

DEFF Research Database (Denmark)

Davies, Michael Jonathan; Hawkins, Clare Louise

2004-01-01

Electron paramagnetic resonance (EPR) spin trapping was originally developed to aid the detection of low-molecular-mass radicals formed in chemical systems. It has subsequently found widespread use in biology and medicine for the direct detection of radical species formed during oxidative stress...... tumbling radicals are often broad and relatively poor in distinctive features, a number of techniques have been developed that allow a wealth of information to be obtained about the nature, site, and reactions of such radicals. This article summarizes recent developments in this area and reviews selected...... examples of radical formation on proteins....

Antioxidant status of neonates exposed in utero to tobacco smoke.

Science.gov (United States)

Fayol, L; Gulian, J M; Dalmasso, C; Calaf, R; Simeoni, U; Millet, V

2005-01-01

To investigate the influence of maternal smoke exposure on neonatal and maternal antioxidant status, 39 mothers who were active smokers, 14 mothers exposed to environmental tobacco smoke (ETS), 17 controls, and their newborns were included in a prospective, controlled study. Plasma total antioxidant capacity, measured as total radical-trapping antioxidant parameter (TRAP) and ferric reducing antioxidant power (FRAP), and concentrations of specific antioxidants were measured in cord and in maternal blood. A similar, significant increase in ceruloplasmin concentration was observed in neonates born to actively smoking mothers and in those born to ETS exposed mothers. Uric acid and TRAP concentrations were significantly increased in ETS-exposed newborns and their mothers, compared to newborns and mothers from the active smoking and no-exposure groups with a trend towards increased uric acid, TRAP and FRAP concentrations being observed in the active smokers group. Neonatal and maternal antioxidant concentrations correlated significantly, except for ceruloplasmin. Cord blood vitamin A, E and C concentrations were unaffected by smoke exposure. These results show that maternal active smoking as well as ETS exposure significantly affect neonatal and maternal antioxidant status. Copyright (c) 2005 S. Karger AG, Basel

The Antioxidant Capacities and Total Phenolic Contents of Some Medicinal Plants in Iran

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Ali Mirzaei

2011-12-01

Full Text Available Background & Objectives: Free radicals are highly reactive molecules may cause great damage to cell membranes and DNA and Result in inducing oxidation DNA mutations leading to cancer, degenerative, and other diseases. Plant antioxidant derived may be preventive of free radical damages. Methods & Materials: The Stems and flower sample of plants air-dried, finely ground and were extracted by ethanol: water (70:30 for 48 h. Extracts were filtered and dried under vacuum. The antioxidant activity of five ethanolic extract of medicinal plants (Descurainia Sophia, Plantago major, Trachyspermum copticum L, Coriandrum sativum and Trigonella foenum-graecum from Iran were analysed by five different methods [1,1-diphenyl-2-picrylhydrazyl (DPPH radical, 2,2,azinobis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS radical cation, Ferric-reducing antioxidant power assay (FRAP, phosphomolybdenum (PMB and reducing power (RP]. In addition, for determination of antioxidant components total phenolic content was also analyzed. Results: The total phenolic content of medicinal plant ranges from 74 to 154.3 mg Gallic acid/g extract as measured by the Folin–Ciocalteau method. Values of DPPH varied from 15.5 to 19.6 µmol trolex/g. FRAP ranged from 124.2 to 753 µmol of Fe(II/g extract. Antioxidant activity of the Plantago major was always higher compared to the other plants extracts values of total phenols content and antioxidant capacity by DPPH, ABTS, FRAP, (154.33 mg GAE/g, 1856 µmol trolox, 750 µmol trolox and 1169 µmol of Fe(II/g, extract respectively. The range of total antioxidant activity by phosphomolybdenum method was 513.3 to 870 µmol trolox/g. The reducing ability of the tested extracts was between 0.31-1.26. Plantago majorwas also highest activity in both tests. Conclusion: This study clearly demonstrated that Plantago major crude extract exhibit significant antioxidant activity.

Phytochemical screening, free radical scavenging, antioxidant activity and phenolic content of Dodonaea viscosa

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Riaz Tauheeda

2012-01-01

Full Text Available The purpose of this study was to evaluate the antioxidant potential of Dodonaea viscosa Jacq. Methanolic extract of the plant was dissolved in distilled water and partitioned with n-hexane, chloroform, ethyl acetate and nbutanol sequentially. Phytochemical screening showed presence of phenolics, flavonoides and cardiac glycosides in large amount in chloroform, ethyl acetate and n-butanol fraction. The antioxidant potential of all these fractions and remaining aqueous fraction was evaluated by four methods: 1,1-Diphenyl-2-picrylhydrazyl (DPPH free radical scavenging activity, total antioxidant activity, Ferric Reducing Antioxidant Power (FRAP assay and ferric thiocyanate assay along with determination of their total phenolics. The results revealed that ethyl acetate soluble fraction exhibited highest percent inhibition of DPPH radical as compared to other fractions. It showed 81.14 ± 1.38% inhibition of DPPH radical at a concentration of 60 μg/ml. The IC50 of this fraction was found to be 33.95 ± 0.58 μg/ml, relative to butylated hydroxytoluene (BHT, having IC50 of 12.54 ± 0.89 μg/mL. It also showed highest FRAP value (380.53 ± 0.74 μM of trolox equivalents as well as highest total phenolic contents (208.58 ± 1.83 GAE μg/g and highest value of inhibition of lipid peroxidation (58.11 ± 1.49% at concentration of 500 μg/ml as compared to the other studied fractions. The chloroform fraction showed highest total antioxidant activity i.e.1.078 ± 0.59 (eq. to BHT.

Total Phenolic, Flavonoids and Antioxidant Capacity of Some Medicinal and Aromatic Plants

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Melinda Nagy

2014-11-01

Full Text Available Abstract: Antioxidants are substances that protect cells from the induced oxidative stress damage caused by unstable molecules known as free radicals that. Antioxidants neutralize free radicals as a natural by-product of normal cell processes. In the present study,were evaluated  the phenolic and flavonoids contents as well as the antioxidant capacity of seeds from  the Lamiaceae and Apiaceae family: fennel  (Foeniculum vulgare, dill (Anethum graveolens and rosemary (Rosmarinus officinalis . (Sreemoyee Ch. et. al., 2012 The main objective of the study was the comparative assessment of the phenolic and flavonoid compounds from dill, rosemary and fennel methanolic extracts correlated with their  antioxidant activity. Both total phenolic content and flavonoids content of the seeds samples were measured spectrophotometrically using the Folin-Ciocalteu assay and a chromogenic system of NaNO2–Al(NO33–NaOH, respectively.. Antioxidant capacity was determined by 2,2-DPPH method. Results strongly showed that Rosmarinus officinalis extract has the most effective antioxidant capacity in scavenging DPPH radicals, while Foeniculum vulgare and Anethum graveolens were less active. The total phenolic content was within 773,14 and 3367,24mg GAE/ 100g while the concentration in flavonoids was between 231,84 and 1325,53 QEg/100g dry seeds.  

Biological activity of clovers - free radical scavenging ability and antioxidant action of six Trifolium species.

Science.gov (United States)

Kolodziejczyk-Czepas, Joanna; Nowak, Pawel; Kowalska, Iwona; Stochmal, Anna

2014-10-01

Clovers were chosen on the basis of traditional medicine recommendations, agricultural value, or available information on their promising chemical profiles. This study evaluates and compares free radical scavenging and antioxidant properties of six clover species: Trifolium alexandrinum L. (Leguminosae), Trifolium fragiferum L., Trifolium hybridum L., Trifolium incarnatum L., Trifolium resupinatum var. majus Boiss., and Trifolium resupinatum var. resupinatum L. Free radical scavenging activity of the extracts (1.5-50 µg/ml) was estimated by reduction of 1,1-diphenyl-2-picrylhydrazyl (DPPH(•)) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic) acid (ABTS(•)) radicals. The Trifolium extract effects on total antioxidant capacity of blood plasma were determined by the reduction of ABTS(•+) and DPPH(•) radicals, as well as with the use of the ferric reducing ability of plasma (FRAP) assay. The UPLC analysis of chemical profiles of the examined extracts showed the presence of three or four groups of phenolic substances, including phenolic acids, clovamides, isoflavones, and other flavonoids. The measurements of free radical scavenging and ferric reducing ability of the examined clover extracts revealed the strongest effect for T. alexandrinum. Furthermore, antioxidant activity assays in human plasma have shown protective effects of all extracts against peroxynitrite-induced reduction of total antioxidant capacity. Trifolium plants may be a rich source of bioactive substances with antioxidant properties. The examined extracts displayed free radical scavenging action and partly protected blood plasma against peroxynitrite-induced oxidative stress; however, the beneficial effects of T. alexandrinum and T. incarnatum seem to be slightly higher.

Characterization of beer flavour stability (EPR - spin trapping)

International Nuclear Information System (INIS)

Stasko, A.; Liptakova, M.; Malik, F.

1999-01-01

The beer flavour stability is coupled with free radical degradation processes. Probably, aldehydes produced during the brewery but also generated by stalling are responsible for beer flavour as well as for its breaking down. The storing beer at the lower temperatures and in the dark place inhibits, and otherwise the rising temperature and illumination accelerate the rate of such radical processes. Beers contain naturally occurring radical scavengers - antioxidants which inhibit such unwanted reactions. Then depleting of scavengers results in the breaking down of the beer stability. EPR spin trapping technique was used as monitor such processes and for characterising so the flavour stability of beer. The probe was temperated at 60 grad C in the cavity of EPR spectrometer in the presence of spin trapping agent, N-tert.-butyl-α-phenyl nitrone (PBN) and EPR spectra were recorded for few hours. After beer antioxidants become depleted, free radicals formed by the beer degradation are scavenged by PBN spin trap and this point is characterised with a dramatically increased concentration of the free radicals trapped

Teaching Methods in Nutrition: Free Radicals, Antioxidants, and Human Disease.

Science.gov (United States)

Janowiak, John J.

This article presents a teaching methodology for free radical theory and discusses the role of antioxidants in human health. Free radicals are a normal byproduct of respiration, which allows the body to use oxygen, liberate energy, and dispose of harmful substances. The body's antioxidants and nutritional antioxidants quench most of the free…

Kinetics and structure-activity relationship of dendritic bridged hindered phenol antioxidants to protect styrene against free radical induced peroxidation

Science.gov (United States)

Li, Cui-Qin; Guo, Su-Yue; Wang, Jun; Shi, Wei-Guang; Zhang, Zhi-Qiu; Wang, Peng-Xiang

2017-12-01

A series of dendritic poly(amido-amine) (PAMAM) bridged hindered phenols antioxidants were synthesized. The active antioxidant group (3-(3,5-di- tert-butyl-4-hydroxyphenyl)propionic acid) was attached to two generations of PAMAM dendrimers, and their structure was verified by nuclear magnetic resonance (NMR) and fourier transform infrared spectra (FT-IR). The antioxidant abilities of the dendritic phenols to inhibit the oxidation of styrene were evaluated and the relationships between the length of core, the generation of dendrimers and the antioxidant activities were established. The reaction kinetics of scavenging peroxyl radicals was followed by oxygen consumption. The inhibition time ( t inh) values showed the dendritic phenols had the ability of scavenging peroxyl radicals, and that the antioxidant ability increased with the increasing length of the core and the generation. The kinetic analysis demonstrated that dendritic phenols could slow the rate of styrene peroxidation induced by AIBN, as shown by the number of trapping ROO· ( n), and this role was in accordance with that of the t inh values.

Total flavonoid content and formulation antioxidant cream stem of jatropha multifida l.

Science.gov (United States)

Dwi Franyoto, Yuvianti; Kusmita, Lia; Mutmainah; Demma Angrena, Riega

2018-05-01

Free radical induced oxidative stress that influences the occurrence of various degenerative diseases such as cancer, coronary heart disease and premature aging. Stems of Jatropha multifida L are known to contain flavanoid compounds have antioxidant activity. A study has been carried out to determine antioxidant potential of stems of Jatropha multifida L. Initially, material was macerated gradually with ethanol. The extract obtained was filtered and evaporated. Determination of total flavanoid contents (TFC) using spectrophotometric methods. The antioxidant potential of this extract was evaluated by 2, 2-diphenyl-1- picrylhydrazyl (DPPH) radical scavenging assay. In the DPPH radical-scavenging activities, the extract had the antioxidant activity (IC50 = 72 ± 0.01 μg/ml). The results showed the extracts of Jatropha multifida L. could be considered as natural antioxidants and may be useful for curing diseases arising from oxidative deterioration. The formulation comprises with 5% of extract and was formulated using fusion method. The evaluation of the formulated cream showed good results and can be good potential for cosmetic product development.

In vitro antioxidant and free radical scavenging activity of different parts of Tabebuia pallida growing in Bangladesh.

Science.gov (United States)

Rahman, Md Mahbubur; Islam, Md Badrul; Biswas, Mohitosh; Khurshid Alam, A H M

2015-10-30

In humans, many diseases are associated with the accumulation of free radicals. Antioxidants can scavenge free radicals and minimize their impact. Therefore, the search for naturally occurring antioxidants of plant origin is imperative. Here, we aimed to investigate the antioxidant and free radical scavenging properties of methanolic extracts from Tabebuia pallida (T. pallida) stem bark (TPSB), root bark (TPRB), leaves (TPL), and flowers (TPF). The antioxidant and free radical scavenging activity were determined by several standard methods using spectrophotomer. Total phenolic and flavonoid contents were estimated using Folin-Ciocalteu reagent and aluminum chloride colorimetric assay methods, respectively. Among the extracts, TPL showed the highest total antioxidant capacity followed by TPRB, TPF, and TPSB. Based on DPPH and hydroxyl radical scavenging activity, TPL showed strong scavenging activity (91.05 ± 1.10 and 62.00 ± 0.57) with IC50 of 9.20 ± 0.28 and 46.00 ± 2.84 μg/mL, respectively when compared with standard BHT (IC50 of 7.00 ± 0.25 μg/mL) and CA (75.00 ± 0.14 μg/mL). These results suggest that TPL had the highest radical scavenging activity among the extractives that closely resembled the standard's. In lipid peroxidation inhibition assay, TPL exhibited the most potent inhibitory activity (83.18 ± 2.12 %) with IC50 of 12.00 ± 2.12 μg/mL, which closely resembled standard CA (IC50 of 10.50 ± 0.28 μg/mL). Also, the reducing capacity on ferrous ion was in the following order: TPL > TPRB > TF > TPSB. The phenolic and flavonoid contents of TPL were higher than other extractives. A positive correlation (p value free radical (DPPH(·) and (·)OH) scavenging efficiencies and lipid peroxidation inhibition activity. Methanolic extract of T. pallida leaf is a potential source of natural antioxidants and serves as an effective free radical scavenger and/or inhibitor. Hence, T. pallida might be a good plant-based pharmaceutical product for several

Effect of Free Radicals & Antioxidants on Oxidative Stress: A Review

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Ashok Shinde

2012-01-01

Full Text Available Recently free radicals have attracted tremendous importance in the field of medicine including dentistry and molecular biology. Free radicals can be either harmful or helpful to the body. When there is an imbalance between formation and removal of free radicals then a condition called as oxidative stress is developed in body. To counteract these free radicals body has protective antioxidant mechanisms which have abilities to lower incidence of various human morbidities and mortalities. Many research groups in the past have tried to study and confirm oxidative stress. Many authors also have studied role of antioxidants in reducing oxidative stress. They have come across with controversial results and furthermore it is not yet fully confirmed whether oxidative stress increases the need for dietary antioxidants. Recently, an association between periodontitis and cardiovascular disease has received considerable attention. Various forms of antioxidants have been introduced as an approach to fight dental diseases and improve general gingival health. The implication of oxidative stress in the etiology of many chronic and degenerative diseases suggests that antioxidant therapy represents a promising avenue for treatment. This study was conducted with the objective of reviewing articles relating to this subject. A Pub Med search of all articles containing key words free radicals, oxidative stress, and antioxidants was done. A review of these articles was undertaken.

Uric acid contributes greatly to hepatic antioxidant capacity besides protein.

Science.gov (United States)

Mikami, T; Sorimachi, M

2017-12-20

Uric acid is the end-product of purine nucleotide metabolism and an increase in uric acid concentration in the body results in hyperuricemia, ultimately leading to gout. However, uric acid is a potent antioxidant and interacts with reactive oxygen species (ROS) to be non-enzymatically converted to allantoin. Uric acid accounts for approximately 60 % of antioxidant capacity in the plasma; however, its contribution to tissue antioxidant capacity is unknown. In this study, the contribution of uric acid to tissue antioxidant capacity and its conversion to allantoin by scavenging ROS in tissue were examined. The results showed that a decrease in hepatic uric acid content via allopurinol administration significantly reduced hepatic total-radical trapping antioxidant parameter (TRAP) content in protein-free cytosol. Additionally, treating protein-free cytosol with uricase led to a further reduction of hepatic TRAP content. Allantoin was also detected in the solution containing protein-free cytosol that reacted with ROS. These findings suggest that in the absence of protein, uric acid contributes greatly to antioxidant capacity in the liver, where uric acid is converted to allantoin by scavenging ROS.

Cytotoxicity, Total Phenolic Contents and Antioxidant Activity of the ...

African Journals Online (AJOL)

The leaves of Annona muricata were extracted using ethanol and the extracts were evaluated for cytotoxicity using Brine Shrimp Lethality Assay, total phenolic content (TPC) and antioxidant activity using DPPH radical scavenging assay. The crude extract showed 73.33 % mortality at 1000 μg/mL concentration and its ...

Measurement of antioxidant activity with trifluoperazine dihydrochloride radical cation

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M.N. Asghar

2008-06-01

Full Text Available A novel, rapid and cost-effective trifluoperazine dihydrochloride (TFPH decolorization assay is described for the screening of antioxidant activity. A chromogenic reaction between TFPH and potassium persulfate at low pH produces an orange-red radical cation with maximum absorption at 502 nm in its first-order derivative spectrum. TFPH was dissolved in distilled water to give a 100 mM solution. The TFPH radical cation solution was made by reacting 0.5 mL of the solution with K2S2O8 (final concentration: 0.1 mM and diluting to 100 mL with 4 M H2SO4 solution. A linear inhibition of color production was observed with linearly increasing amounts of antioxidants, with correlation coefficients (R² ranging from 0.999 to 0.983. The antioxidant capacity of standard solutions of an antioxidant was evaluated by comparing with the inhibition curve using Trolox as the standard. Comparison of antioxidant capacity determined with this newly developed TFPH assay and with the well-known 2,2'-azinobis-[3-ethylbenzthiazoline-6-sulfonic acid] (ABTS-persulfate decolorization assay indicated the efficacy and sensitivity of the procedure. The proposed assay is less expensive (costs about US$4 per 100 assays and requires only 20 min for preparation of radical cation solution in comparison with ABTS assay, in which almost 12-16 h are required for preparation of a stable ABTS radical cation solution. The present assay has the advantage over ABTS assay that it can be used to measure the antioxidant activity of the samples, which are naturally found at a pH as low as 1, because the radical cation itself has been stabilized at low pH.

AKTIVITAS ANTIOKSIDAN DAN KADAR FENOLIK TOTAL DARI GANGGANG MERAH (Gracilaria verrucosa L. [Antioxidant Activity and Total Phenolic Content of Red Sea Weed (Gracilaria verrucosa L.

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Lydia Ninan Lestario*

2008-12-01

Full Text Available The aims of this study were to compare the antioxidant activity and the total phenolic content of red sea weed (Gracilaria verrucosa L. from extract of methanol, ethanol, acetone, chloroform and hexane; and the correlation between total phenolic content and the antioxidant activity of each extract; then to determine the chlorophyll a, chlorophyll b, and carotene content of each extract and their correlation with the free radical scavenging activity as well. The antioxidant activity were measured by free radical scavenging method with DPPH and by reducing power method with K4Fe(CN6 as standard, whereas the total phenolic content was measured by Folin Ciocalteu method with gallic acid as standard. Chlorophyll a, chlorophyll b, and carotene were determined by spectrophotometric method based on Lambert-Beer law. The data of antioxidant activity and total phenolic content were statistically analyzed by Randomized Completely Block Design (RCBD with five kinds of solvents as treatments and five replications. Honestly Significant Difference Test (HSDT was used to compare the difference of treatments; whereas the chlorophyll a, chlorophyll b, and carotene content were not statistically analyzed since they were only supplement data. The results showed that the highest of the antioxidant activity by free radical scavenging method was found in acetone extract : 43.43% (BHT: 84.15%; whereas by reducing power method was found in chloroform extract : 0.1756 meq K4Fe(CN6/g extract (BHT : 6.1767 meq K4Fe(CN6/g extract; and the highest of the total phenolic content was also found in acetone extract : 45.29 mg /g extract. There were close correlation between phenolic content and antioxidant activity both by free radical scavenging method and by reducing power method with r (coefficient correlation respectivelly 0.89 and 0.91.Chlorophyll a and carotene had also close correlation with the free radical scaveging activity, but not for chlorophyll b.

A multiple free-radical scavenging (MULTIS) study on the antioxidant capacity of a neuroprotective drug, edaravone as compared with uric acid, glutathione, and trolox.

Science.gov (United States)

Kamogawa, Erisa; Sueishi, Yoshimi

2014-03-01

Edaravone (3-methyl-1-phenyl-2-pyrazoline-5-one) is a neuroprotective drug that has been used for brain ischemia injury treatment. Because its activity is speculated to be due to free radical scavenging activity, we carried out a quantitative determination of edaravone's free radical scavenging activity against multiple free radical species. Electron spin resonance (ESR) spin trapping-based multiple free-radical scavenging (MULTIS) method was employed, where target free radicals were hydroxyl radical, superoxide anion, alkoxyl radical, alkylperoxyl radical, methyl radical, and singlet oxygen. Edaravone showed relatively high scavenging abilities against hydroxyl radical (scavenging rate constant k=2.98×10(11) M(-1) s(-1)), singlet oxygen (k=2.75×10(7) M(-1) s(-1)), and methyl radical (k=3.00×10(7) M(-1) s(-1)). Overall, edaravone's scavenging activity against multiple free radical species is as robust as other known potent antioxidant such as uric acid, glutathione, and trolox. A radar chart illustration of the MULTIS activity relative to uric acid, glutathione, and trolox indicates that edaravone has a high and balanced antioxidant activity with low specificity. Copyright © 2014 Elsevier Ltd. All rights reserved.

HPLC-Analysis of Polyphenolic Compounds in Gardenia jasminoides and Determination of Antioxidant Activity by Using Free Radical Scavenging Assays

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Riaz Uddin

2014-05-01

Full Text Available Purpose: Gardenia jasminoides is a traditional medicinal plant rich in anti-inflammatory flavonoids and phenolic compounds and used for the treatment of inflammatory diseases and pain. In this present study, antioxidant potential of Gardenia jasminoides leaves extract was evaluated by using various antioxidant assays. Methods: Various antioxidant assays such as 1, 1-diphenyl-2-picrylhydrazyl (DPPH radical scavenging assay, reducing power and total antioxidant capacity expressed as equivalent to ascorbic acid were employed. Moreover, phenolic compounds were detected by high-performance liquid chromatography (HPLC coupled with diode-array detection. Results: The methanol extract showed significant free radical scavenging activities in DPPH radical scavenging antioxidant assays compared to the reference antioxidant ascorbic acid. Total antioxidant activity was increased in a dose dependent manner. The extract also showed strong reducing power. The total phenolic content was determined as 190.97 mg/g of gallic acid equivalent. HPLC coupled with diode-array detection was used to identify and quantify the phenolic compounds in the extracts. Gallic acid, (+-catechin, rutin hydrate and quercetin have been identified in the plant extracts. Among the phenolic compounds, catechin and rutin hydrate are present predominantly in the extract. The accuracy and precision of the presented method were corroborated by low intra- and inter-day variations in quantitative results in leaves extract. Conclusion: These results suggest that phenolic compounds and flavonoids might contribute to high antioxidant activities of Gardenia jasminoides leaves.

Spin Trapping Radicals from Lipid Oxidation in Liposomes in the Presence of Flavonoids

International Nuclear Information System (INIS)

Arshad, N.

2013-01-01

Interactions of four structurally related flavonoids - quercetin, rutin, morin and catechin with peroxyl radicals using liposome/N-tert-butyl-alpha-phenylnitrone (PBN) and liposome -(4-pyridyl-N-oxide)-N-tert-butylnitrone (POBN)-spin trap systems have been studied through spin trapping ESR. Results obtained were different from that of conjugated diene analysis experiments, where lag phases indicated radical scavenging activity of all the flavonoids. No clear lag phase was observed in ESR experiments under same conditions. In the presence of flavonoids decreasing ESR signals of spin adducts in PBN, while no or negligibly smaller spin adducts with POBN system were observed which may be attributed to the possibility that spin traps interacted with free radicals. Experiments with buffer/spin trap systems without liposome revealed that spin adducts were only stable with catechin and destroyed by quercetin, rutin and morin in buffer/spin trap systems. These results further assured that quercetin, rutin and morin not only interacted with peroxyl radicals but also with spin adducts. (author)

Determination of total phenolic compound contents and antioxidant capacity of persimmon skin

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M Mohamadi

2012-05-01

Full Text Available Due to the adverse side effects of synthetic antioxidants, the search for natural and safe antioxidants has become crucial. In this study, the total phenolic compound contents and antioxidants activity of persimmon skin was investigated. The extraction was carried out by means of maceration method using ethanol and methanol solvents with ratio of 1 part persimmon skin to 5 parts of solvents. Afterwards, the total phenolic compounds and antioxidants activity was measured. According to the results, ethanolic and methanolic extracts contained 255.6 and 214.15 mg gallic acid per 100 g of persimmon skin, respectively. Moreover, ethanolic extracts showed a higher activity for scavenging free radicals compared to methanolic extracts.

Cupric ion reducing antioxidant capacity assay for antioxidants in human serum and for hydroxyl radical scavengers.

Science.gov (United States)

Apak, Reşat; Güçlü, Kubilay; Ozyürek, Mustafa; Bektaşoğlu, Burcu; Bener, Mustafa

2010-01-01

, 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.

Detection of free radicals by radical trapping and 15N NMR spectroscopy in copolymerization of methyl acrylate and styrene

NARCIS (Netherlands)

Kelemen, P.; Klumperman, B.

2003-01-01

The macroradicals taking part in the copolymn. of Me acrylate and styrene were trapped by reaction with a 15N labeled stable nitroxyl radical at 70 DegC. The nitroxyl radical is formed in situ from a thermally instable alkoxyamine precursor. 15N NMR spectroscopy is applied to detect the trapping

Quantum Chemical Study on the Antioxidation Mechanism of Piceatannol and Isorhapontigenin toward Hydroxyl and Hydroperoxyl Radicals.

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Yang Lu

Full Text Available A systematic study of the antioxidation mechanisms behind hydroxyl (•OH and hydroperoxyl (•OOH radical scavenging activity of piceatannol (PIC and isorhapontigenin (ISO was carried out using density functional theory (DFT method. Two reaction mechanisms, abstraction (ABS and radical adduct formation (RAF, were discussed. A total of 24 reaction pathways of scavenging •OH and •OOH with PIC and ISO were investigated in the gas phase and solution. The thermodynamic and kinetic properties of all pathways were calculated. Based on these results, we evaluated the antioxidant activity of every active site of PIC and ISO and compared the abilities of PIC and ISO to scavenge radicals. According to our results, PIC and ISO may act as effective •OH and •OOH scavengers in organism. A4-hydroxyl group is a very important active site for PIC and ISO to scavenge radicals. The introducing of -OH or -OCH3 group to the ortho-position of A4-hydroxyl group would increase its antioxidant activity. Meanwhile, the conformational effect was researched, the results suggest that the presence and pattern of intramolecular hydrogen bond (IHB are considerable in determining the antioxidant activity of PIC and ISO.

Flavanols, proanthocyanidins and antioxidant activity changes during cocoa (Theobroma cacao L.) roasting as affected by temperature and time of processing.

Science.gov (United States)

Ioannone, F; Di Mattia, C D; De Gregorio, M; Sergi, M; Serafini, M; Sacchetti, G

2015-05-01

The effect of roasting on the content of flavanols and proanthocyanidins and on the antioxidant activity of cocoa beans was investigated. Cocoa beans were roasted at three temperatures (125, 135 and 145 °C), for different times, to reach moisture contents of about 2 g 100 g(-1). Flavanols and proanthocyanidins were determined, and the antioxidant activity was tested by total phenolic index (TPI), ferric reducing antioxidant power (FRAP) and total radical trapping antioxidant parameter (TRAP) methods. The rates of flavanol and total proanthocyanidin loss increased with roasting temperatures. Moisture content of the roasted beans being equal, high temperature-short time processes minimised proanthocyanidins loss. Moisture content being equal, the average roasting temperature (135 °C) determined the highest TPI and FRAP values and the highest temperature (145 °C) determined the lowest TPI values. Moisture content being equal, low temperature-long time roasting processes maximised the chain-breaking activity, as determined by the TRAP method. Copyright © 2014 Elsevier Ltd. All rights reserved.

A comparative assessment of antioxidant properties, total phenolic content of einkorn, wheat, barley and their malts.

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Fogarasi, Attila-Levente; Kun, Szilárd; Tankó, Gabriella; Stefanovits-Bányai, Eva; Hegyesné-Vecseri, Beáta

2015-01-15

Two einkorn wheat, one barley, three optional winter cultivation wheat and five winter cultivation wheat samples harvested in Hungary in 2011, and their malts were evaluated for their DPPH radical and ABTS radical cation scavenging activity, ferric reduction capacity (FRAP) and total phenolic content (TPC). All einkorn and barley samples exhibited significant antioxidant activities determined by DPPH and ABTS radical scavenging activities. The einkorn samples show higher polyphenol content than the other wheat samples. In all cases the barley sample had the highest antioxidant potential and polyphenol content. The einkorn malts had high DPPH and ABTS radical cation scavenging activities, but the phenolic content was lower against wheat samples. There was significant difference between the antioxidant potential of optional and winter cultivation wheat samples except on ABTS scavenging activities. Einkorn wheat is potentially a new raw material to produce organic beer that might have beneficial effects with its increased antioxidant potential. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antioxidant activity of Sempervivum tectorum and its components.

Science.gov (United States)

Sentjurc, Marjeta; Nemec, Marjana; Connor, Henry D; Abram, Veronika

2003-04-23

The antioxidant properties of components of leaf extracts of the evergreen plant, Sempervivum tectorum (ST), have been evaluated using UV irradiated liposomal systems containing the spin trap 5-(diethoxyphosphoryl)-5-methyl-pyrroline-N-oxide. Decreases in free radical activity in the liposomal systems as measured by electron paramagnetic resonance (EPR) spectroscopy demonstrate that the lipophilic ST juice components, kaempferol (KA) and kaempferol-3-glucoside (KG) contribute significantly to the antioxidant properties of the juice. EPR spectral simulation established the presence of oxygen and carbon centered free radical adducts. The mixtures with low pH, citric and malic acid, and ST juice reveal increased EPR signals from oxygen centered radicals in comparison to the control, pointing to the important role of pH in oxygen radical formation. Parallel assays that measured thiobarbituric acid related substances confirm the antioxidant effects of KA and KG and explain the results of spin trapping experiments complicated by low pH's.

The Antioxidant Activities and Total Phenolic of Artemisia Martima, Achillea Millefolium and Matricaria Recutica

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A Mirzaei

2010-10-01

Full Text Available Introduction & Objective: Consumption of plant derived antioxidant contributes to reducing risks of certain chronic and degenerative diseases. The aim of the present study was to study the antioxidant activities and total phenolic of Artemisia Martima, Achillea Millefolium and Matricaria Recutica Materials & Methods: The present study was conducted at Yasuj University of Medical Sciences in 2009. The Stem and flower sample of plants were air-dried, and then grinded and were finally extracted by ethanol: water (70: 30 for 48 h in room temperature. Extracts were filtered and dried under vacuum system. The antioxidant activity of three ethanol extract of the medicinal plants, Artemisia martima, Achillea millefolium and Matricaria recutica, were analyzed by five different methods (1,1-diphenyl-2-picrylhydrazyl (DPPH radical, 2, 20azinobis- (3-ethylbenzthiazoline -6-sulphonic acid (ABTS radical cation,Ferric-reducing antioxidant power assay (FRAP, phosphomolybdenum (PMB and reducing power ( RP. In addition, for determination of antioxidant components, the total phenolic content was also analyzed. The collected data was analyzed by SPSS software. Results: For all antioxidant activity assays, Artemisia martima had the highest antioxidant activity value and also total phenol content. Antioxidant capacity analyses revealed that the FRAP and DPPH had comparable results. Antioxidant activity at 1 mg/mL, in ABTS were in the order Artemisia martima> Achillea millefolium> Matricaria recutica. Similar trend was observed for PMB content. RP, FRAP and DPPH were in the order Artemisia martima> Matricaria recutica > Achillea millefolium . Conclusion: The extracts showed a variety of antioxidant activities in all antioxidant assay system. This study demonstrated that Artemisia martima crude extract exhibit significant antioxidant activity.

Plasma total antioxidant capacity is associated with dietary intake and plasma level of antioxidants in postmenopausal women.

Science.gov (United States)

Wang, Ying; Yang, Meng; Lee, Sang-Gil; Davis, Catherine G; Kenny, Anne; Koo, Sung I; Chun, Ock K

2012-12-01

Increased plasma total antioxidant capacity (TAC) has been associated with a high consumption of fruits and vegetables. However, limited information is available on whether plasma TAC reflects the dietary intake of antioxidants and the levels of individual antioxidants in plasma. By using three different assays, the study aimed to determine if plasma TAC can effectively predict dietary intake of antioxidants and plasma antioxidant status. Forty overweight and apparently healthy postmenopausal women were recruited. Seven-day food records and 12-h fasting blood samples were collected for dietary and plasma antioxidant assessments. Plasma TAC was determined by vitamin C equivalent antioxidant capacity (VCEAC), ferric-reducing ability of plasma (FRAP) and oxygen radical absorbance capacity (ORAC) assays. TAC values determined by VCEAC were highly correlated with FRAP (r=0.79, Pantioxidants and represents more closely the plasma antioxidant levels than ORAC and FRAP. Copyright © 2012 Elsevier Inc. All rights reserved.

Free Radicals and Antioxidants in Cardiovascular Health and Disease

African Journals Online (AJOL)

Free radicals can be overproduced or the natural antioxidant system defenses weakened, first resulting in oxidative stress, and then leading to oxidative injury ... Keywords: Oxidative stress, cardiovascular disease, atherosclerosis, inflammation, cell signaling and transduction mechanisms, antioxidants, dietary phenolics.

Free radical-scavenging capacity, antioxidant activity and phenolic content of Pouzolzia zeylanica

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PEIYUAN LI

2011-05-01

Full Text Available Pouzolzia zeylanica was extracted with different solvents (acetone, ethyl acetate and petroleum ether, using different protocols (cold-extraction and Soxhlet extraction. To evaluate the antiradical and antioxidant abilities of the extracts, four in vitro test systems were employed, i.e., DPPH, ABTS and hydroxyl radical scavenging assays and a reducing power assay. All extracts exhibited outstanding antioxidant activities that were superior to that of butylated hydroxytoluene. The ethyl acetate extracts exhibited the most significant antioxidant activities, and cold-extraction under stirring seemed to be the more efficacious method for acquiring the predominant antioxidants. Furthermore, the antioxidant activities and total phenolic (TP content of different extracts followed the same order, i.e., there is a good correlation between antioxidant activities and TP content. The results showed that these extracts, especially the ethyl acetate extracts, could be considered as natural antioxidants and may be useful for curing diseases arising from oxidative deterioration.

Evaluation of antioxidant, free radical scavenging and antimicrobial, activity of Quercus incana Roxb.

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Rizwana eSarwar

2015-11-01

Full Text Available Considering the indigenous utilization of Quercus incana Roxb., the present study deals with the investigation of antioxidant, free radical scavenging activity, total phenolic content and antimicrobial activity of Quercus incana Roxb. In vitro antioxidant activity of the plant fractions were determined by DPPH and NO scavenging method. Total phenolic contents were determined by gallic acid equivalent (GAE and antimicrobial activities were determined by agar well diffusion method. It was observed that Quercus incana Roxb. showed significant antibacterial activity against Gram-positive and Gram-negative bacteria. n-Butanol fraction showed maximum activity against Micrococcus leuteus with 19 mm zone of inhibition. n-Butanol fraction of Quercus incana Roxb. showed immense antifungal activity against Aspergillus niger (32 mm ± 0.55 and Aspergillus flavus (28 mm ± 0.45. Similarly n-butanol fraction showed relatively good antioxidant activity with IC50 value of 55.4 ± 0.21μg/mL. The NO scavenging activity of ethyl acetate fraction (IC50 = 23.21 ± 0.31 μg/mL was fairly good compared to other fractions. The current study of Quercus incana Roxb. suggests the presences of synergetic action of some biological active compounds that may be present in the leaves of medicinal plant. Further studies are needed to better characterize the important active constituents responsible for the antimicrobial, antioxidant and free radical scavenging activity.

The validity and reproducibility of food-frequency questionnaire–based total antioxidant capacity estimates in Swedish women

Science.gov (United States)

Total antioxidant capacity (TAC) provides an assessment of antioxidant activity and synergistic interactions of redox molecules in foods and plasma. We investigated the validity and reproducibility of food frequency questionnaire (FFQ)–based TAC estimates assessed by oxygen radical absorbance capaci...

Proximate, mineral composition, antioxidant activity, and total ...

African Journals Online (AJOL)

... of protein supplement, valuable minerals and dietary antioxidants. They can serve as scavengers of free radicals reported to be associated with occurrence of chronic and degenerative diseases such as cardiovascular diseases. Keywords: Peppers, phytochemicals, Nutritional composition, Free radicals, Diseases ...

Oxidation of spin-traps by chlorine dioxide (ClO2) radical in aqueous solutions: first ESR evidence of formation of new nitroxide radicals.

Science.gov (United States)

Ozawa, T; Miura, Y; Ueda, J

1996-01-01

The reactivities of the chlorine dioxide (ClO2), which is a stable free radical towards some water-soluble spin-traps were investigated in aqueous solutions by an electron spin resonance (ESR) spectroscopy. The ClO2 radical was generated from the redox reaction of Ti3+ with potassium chlorate (KClO3) in aqueous solutions. When one of the spin-traps, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), was included in the Ti3+-KClO3 reaction system, ESR spectrum due to the ClO2 radical completely disappeared and a new ESR spectrum [aN(1) = 0.72 mT, aH(2) = 0.41 mT], which is different from that of DMPO-ClO2 adduct, was observed. The ESR parameters of this new ESR signal was identical to those of 5,5-dimethylpyrrolidone-(2)-oxyl-(1) (DMPOX), suggesting the radical species giving the new ESR spectrum is assignable to DMPOX. The similar ESR spectrum consisting of a triplet [aN(1) = 0.69 mT] was observed when the derivative of DMPO, 3,3,5,5-tetramethyl-1-pyrroline N-oxide (M4PO) was included in the Ti3+-KClO3 reaction system. This radical species is attributed to the oxidation product of M4PO, 3,3,5,5-tetramethylpyrrolidone-(2)-oxyl-(1) (M4POX). When another nitrone spin-trap, alpha-(4-pyridyl-1-oxide)-N-t-butylnitrone (POBN) was used as a spin-trap, the ESR signal intensity due to the ClO2 radical decreased and a new ESR signal consisting of a triplet [aN(1) = 0.76 mT] was observed. The similar ESR spectrum was observed when N-t-butyl-alpha- nitrone (PBN) was used as a spin-trap. This ESR parameter [a(N)(1) = 0.85 mT] was identical to the oxidation product of PBN, PBNX. Thus, the new ESR signal observed from POBN may be assigned to the oxidation product of POBN, POBNX. These results suggest that the ClO2, radical does not form the stable spin adducts with nitrone spin-traps, but oxidizes these spin-traps to give the corresponding nitroxyl radicals. On the other hand, nitroso spin-traps, 5,5-dibromo-4-nitrosobenzenesulfonate (DBNBS), and 2-methyl-2-nitrosopropane (MNP) did not trap

Evaluation of Antioxidant Activity, Total Flavonoids, Tannins and Phenolic Compounds in Psychotria Leaf Extracts

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Anelise Samara Nazari Formagio

2014-11-01

Full Text Available The antioxidant activity of Psychotria carthagenensis, P. leiocarpa, P. capillacea and P. deflexa (Rubiaceae extracts were investigated, and the concentrations of total phenolics, flavonoids, condensed tannins and flavonols were determined. The chemical compositions of the extracts were investigated using the high performance liquid chromatography (HPLC/PAD method. We used 1,1-diphenyl-1-picrylhydrazyl free radical (DPPH, β-Carotene bleaching and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS radical cations to determine antioxidant activity. The ability to scavenge radical was measured in these experiments by the discoloration of the solution. Concentrations of constituents were measured spectrophotometrically. P. carthagenensis and P. capillacea exhibited the highest antioxidant activity, in the DPPH test, β-carotene bleaching and ABTS system. The highest phenolic, flavonoid, condensed tannin and flavonol concentration was found in P. carthagenensis and P. capillacea extracts. HPLC-PDA analysis of P. carthagenensis and P. capillacea revealed hydroxycinnamic acid (p-coumaric acid. This is the first report on the antioxidant properties and constituent analysis of these Psychotria extracts.

Acute Exercise Increases Plasma Total Antioxidant Status and Antioxidant Enzyme Activities in Untrained Men

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C. Berzosa

2011-01-01

Full Text Available Antioxidant defences are essential for cellular redox regulation. Since free-radical production may be enhanced by physical activity, herein, we evaluated the effect of acute exercise on total antioxidant status (TAS and the plasma activities of catalase, glutathione reductase, glutathione peroxidase, and superoxide dismutase and its possible relation to oxidative stress resulting from exercise. Healthy untrained male subjects (=34 performed three cycloergometric tests, including maximal and submaximal episodes. Venous blood samples were collected before and immediately after each different exercise. TAS and enzyme activities were assessed by spectrophotometry. An increase of the antioxidant enzyme activities in plasma was detected after both maximal and submaximal exercise periods. Moreover, under our experimental conditions, exercise also led to an augmentation of TAS levels. These findings are consistent with the idea that acute exercise may play a beneficial role because of its ability to increase antioxidant defense mechanisms through a redox sensitive pathway.

Spin trapping combined with quantitative mass spectrometry defines free radical redistribution within the oxidized hemoglobin:haptoglobin complex.

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Vallelian, Florence; Garcia-Rubio, Ines; Puglia, Michele; Kahraman, Abdullah; Deuel, Jeremy W; Engelsberger, Wolfgang R; Mason, Ronald P; Buehler, Paul W; Schaer, Dominik J

2015-08-01

Extracellular or free hemoglobin (Hb) accumulates during hemolysis, tissue damage, and inflammation. Heme-triggered oxidative reactions can lead to diverse structural modifications of lipids and proteins, which contribute to the propagation of tissue damage. One important target of Hb׳s peroxidase reactivity is its own globin structure. Amino acid oxidation and crosslinking events destabilize the protein and ultimately cause accumulation of proinflammatory and cytotoxic Hb degradation products. The Hb scavenger haptoglobin (Hp) attenuates oxidation-induced Hb degradation. In this study we show that in the presence of hydrogen peroxide (H2O2), Hb and the Hb:Hp complex share comparable peroxidative reactivity and free radical generation. While oxidation of both free Hb and Hb:Hp complex generates a common tyrosine-based free radical, the spin-trapping reaction with 5,5-dimethyl-1-pyrroline N-oxide (DMPO) yields dissimilar paramagnetic products in Hb and Hb:Hp, suggesting that radicals are differently redistributed within the complex before reacting with the spin trap. With LC-MS(2) mass spectrometry we assigned multiple known and novel DMPO adduct sites. Quantification of these adducts suggested that the Hb:Hp complex formation causes extensive delocalization of accessible free radicals with drastic reduction of the major tryptophan and cysteine modifications in the β-globin chain of the Hb:Hp complex, including decreased βCys93 DMPO adduction. In contrast, the quantitative changes in DMPO adduct formation on Hb:Hp complex formation were less pronounced in the Hb α-globin chain. In contrast to earlier speculations, we found no evidence that free Hb radicals are delocalized to the Hp chain of the complex. The observation that Hb:Hp complex formation alters free radical distribution in Hb may help to better understand the structural basis for Hp as an antioxidant protein. Copyright © 2015 Elsevier Inc. All rights reserved.

Antioxidant Capacities and Total Phenolic Contents of 56 Wild Fruits from South China

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Hua-Bin Li

2010-11-01

Full Text Available In order to identify wild fruits possessing high nutraceutical potential, the antioxidant activities of 56 wild fruits from South China were systematically evaluated. The fat-soluble components were extracted with tetrahydrofuran, and the water-soluble ones were extracted with a 50:3.7:46.3 (v/v methanol-acetic acid-water mixture. The antioxidant capacities of the extracts were evaluated using the ferric reducing antioxidant power (FRAP and Trolox equivalent antioxidant capacity (TEAC assays, and their total phenolic contents were measured by the Folin-Ciocalteu method. Most of these wild fruits were analyzed for the first time for their antioxidant activities. Generally, these fruits had high antioxidant capacities and total phenolic contents. A significant correlation between the FRAP value and the TEAC value suggested that antioxidant components in these wild fruits were capable of reducing oxidants and scavenging free radicals. A high correlation between antioxidant capacity and total phenolic content indicated that phenolic compounds could be the main contributors to the measured antioxidant activity. The results showed that fruits of Eucalyptus robusta, Eurya nitida, Melastoma sanguineum, Melaleuca leucadendron, Lagerstroemia indica, Caryota mitis, Lagerstroemia speciosa and Gordonia axillaris possessed the highest antioxidant capacities and total phenolic contents among those tested, and could be potential rich sources of natural antioxidants and functional foods. The results obtained are very helpful for the full utilization of these wild fruits.

Free radicals and antioxidants in primary fibromyalgia: an oxidative stress disorder?

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Bagis, Selda; Tamer, Lulufer; Sahin, Gunsah; Bilgin, Ramazan; Guler, Hayal; Ercan, Bahadir; Erdogan, Canan

2005-04-01

The role of free radicals in fibromyalgia is controversial. In this study, 85 female patients with primary fibromyalgia and 80 age-, height-, and weight-matched healthy women were evaluated for oxidant/antioxidant balance. Malondialdehyde is a toxic metabolite of lipid peroxidation used as a marker of free radical damage. Superoxide dismutase is an intracellular antioxidant enzyme and shows antioxidant capacity. Pain was assessed by visual analog scale. Tender points were assessed by palpation. Age, smoking, body mass index (BMI), and duration of disease were also recorded. Malondialdehyde levels were significantly higher and superoxide dismutase levels significantly lower in fibromyalgic patients than controls. Age, BMI, smoking, and duration of disease did not affect these parameters. We found no correlation between pain and number of tender points. In conclusion, oxidant/antioxidant balances were changed in fibromyalgia. Increased free radical levels may be responsible for the development of fibromyalgia. These findings may support the hypothesis of fibromyalgia as an oxidative disorder.

Antioxidant and DPPH (1,1-diphenyl-2-picrylhydrazyl Free Radical Scavenging Activities of New the Calix[4]arene-bodipy Derivative

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E. ERDEM

2014-07-01

Full Text Available p-tert-butylcalix[4]arene was synthesized with the condesation reaction of p-tert-butylphenol and formaldehyde in basic conditions and then has derivatized from the both of two hydroxyl position with chloride which is containing donor oxygen atoms. BODIPY compound (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene was synthesized with appropriate pyrrole and aldehyde compounds and then was bonded p-tert-butylcalix[4]arene derivative via lower rim hydroxyl groups.The antioxidant activity of the calix[4]arene-BODIPY compound were determined using β-karotene-linoleic acid system. Moreover, the free radical scavenging activity values were tested with DPPH free radical. The compound showed strong antioxidant activity.Total antioxidant activity of the compound was determined using β–carotenelinoleic acid model system and was found the antioxidant activity of 72,50%. The free radical scavenging activities were determined as 75.19%. Results show that, calix[4]arene-BODIPY compound has the antioxidant activity. 

Antioxidant and free radical scavenging activities of plant extracts ...

African Journals Online (AJOL)

Twenty-two species of medicinal plants collected in the Mexican state of Morelos were selected to evaluate their free radical scavenging and antioxidant activities. The extracts from the aerial parts of the plants were obtained using hexane, acetone and methanol (66 extracts). The initial qualitative screening of antioxidants ...

HPLC-Analysis of Polyphenolic Compounds in Gardenia jasminoides and Determination of Antioxidant Activity by Using Free Radical Scavenging Assays

OpenAIRE

Riaz Uddin; Moni Rani Saha; Nusrat Subhan; Hemayet Hossain; Ismet Ara Jahan; Raushanara Akter; Ashraful Alam

2014-01-01

Purpose: Gardenia jasminoides is a traditional medicinal plant rich in anti-inflammatory flavonoids and phenolic compounds and used for the treatment of inflammatory diseases and pain. In this present study, antioxidant potential of Gardenia jasminoides leaves extract was evaluated by using various antioxidant assays. Methods: Various antioxidant assays such as 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, reducing power and total antioxidant capacity expressed as equival...

Antioxidant capacity and radical scavenging effect of polyphenol rich Mallotus philippenensis fruit extract on human erythrocytes: an in vitro study.

Science.gov (United States)

Gangwar, Mayank; Gautam, Manish Kumar; Sharma, Amit Kumar; Tripathi, Yamini B; Goel, R K; Nath, Gopal

2014-01-01

Mallotus philippinensis is an important source of molecules with strong antioxidant activity widely used medicinal plant. Previous studies have highlighted their anticestodal, antibacterial, wound healing activities, and so forth. So, present investigation was designed to evaluate the total antioxidant activity and radical scavenging effect of 50% ethanol fruit glandular hair extract (MPE) and its role on Human Erythrocytes. MPE was tested for phytochemical test followed by its HPLC analysis. Standard antioxidant assays like DPPH, ABTS, hydroxyl, superoxide radical, nitric oxide, and lipid peroxidation assay were determined along with total phenolic and flavonoids content. Results showed that MPE contains the presence of various phytochemicals, with high total phenolic and flavonoid content. HPLC analysis showed the presence of rottlerin, a polyphenolic compound in a very rich quantity. MPE exhibits significant strong scavenging activity on DPPH and ABTS assay. Reducing power showed dose dependent increase in concentration absorption compared to standard, Quercetin. Superoxide, hydroxyl radical, lipid peroxidation, nitric oxide assay showed a comparable scavenging activity compared to its standard. Our finding further provides evidence that Mallotus fruit extract is a potential natural source of antioxidants which have a protective role on human Erythrocytes exhibiting minimum hemolytic activity and this justified its uses in folklore medicines.

A study of extraction process and in vitro antioxidant activity of total ...

African Journals Online (AJOL)

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 ...

Effect of different cooking methods on total phenolic contents and antioxidant activities of four Boletus mushrooms.

Science.gov (United States)

Sun, Liping; Bai, Xue; Zhuang, Yongliang

2014-11-01

The influences of cooking methods (steaming, pressure-cooking, microwaving, frying and boiling) on total phenolic contents and antioxidant activities of fruit body of Boletus mushrooms (B. aereus, B. badius, B. pinophilus and B. edulis) have been evaluated. The results showed that microwaving was better in retention of total phenolics than other cooking methods, while boiling significantly decreased the contents of total phenolics in samples under study. Effects of different cooking methods on phenolic acids profiles of Boletus mushrooms showed varieties with both the species of mushroom and the cooking method. Effects of cooking treatments on antioxidant activities of Boletus mushrooms were evaluated by in vitro assays of hydroxyl radical (OH·) -scavenging activity, reducing power and 1, 1-diphenyl-2-picrylhydrazyl radicals (DPPH·) -scavenging activity. Results indicated the changes of antioxidant activities of four Boletus mushrooms were different in five cooking methods. This study could provide some information to encourage food industry to recommend particular cooking methods.

Functionalized graphene quantum dots loaded with free radicals combined with liquid chromatography and tandem mass spectrometry to screen radical scavenging natural antioxidants from Licorice and Scutellariae.

Science.gov (United States)

Wang, Guoying; Niu, XiuLi; Shi, Gaofeng; Chen, Xuefu; Yao, Ruixing; Chen, Fuwen

2014-12-01

A novel screening method was developed for the detection and identification of radical scavenging natural antioxidants based on a free radical reaction combined with liquid chromatography with tandem mass spectrometry. Functionalized graphene quantum dots were prepared for loading free radicals in the complex screening system. The detection was performed with and without a preliminary exposure of the samples to specific free radicals on the functionalized graphene quantum dots, which can facilitate charge transfer between free radicals and antioxidants. The difference in chromatographic peak areas was used to identify potential antioxidants. This is a novel approach to simultaneously evaluate the antioxidant power of a component versus a free radical, and to identify it in a vegetal matrix. The structures of the antioxidants in the samples were identified using tandem mass spectrometry and comparison with standards. Fourteen compounds were found to possess potential antioxidant activity, and their free radical scavenging capacities were investigated. The order of scavenging capacity of 14 compounds was compared according to their free radical scavenging rate. 4',5,6,7-Tetrahydroxyflavone (radical scavenging rate: 0.05253 mL mg(-1) s(-1) ) showed the strongest capability for scavenging free radicals. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Role of alkaline-tolerant fungal cellulases in release of total antioxidants from agro-wastes under solid state fermentation

Digital Repository Service at National Institute of Oceanography (India)

Ravindran, C.; Varatharajan, G. R.; Karthikeyan, A.

-wastes and total antioxidant property. The increased antioxidant activity on free radical scavenging was also observed with the increase in pH. Thus, the present study makes it possible to produce nutraceutical ingredients cost-effectively from agricultural wastes....

Electron spin resonance of spin-trapped radicals of amines and polyamines

International Nuclear Information System (INIS)

Mossoba, M.M.; Rosenthal, Ionel; Riesz, Peter

1982-01-01

The reactions of hydroxyl radicals with methylamine, dimethylamine, trimethylamine, diethylamine, sec-butylamine, ethylene-diamine, 1,3-diaminopropane, putrescine, cadaverine, 1,7-diaminoheptane, ornithine, spermidine, spermine, agmatine, and arcaine in aqueous solutions have been investigated by spin-trapping and esr. Hydroxyl radicals were generated by the uv photolysis of H 2 O 2 and 2-methyl-2-nitrosopropane (MNP) was used as the spin-trap. The effects of ionizing radiation on the same polyamines in the polycrystalline state were also investigated. The free radicals produced by ν-radiolysis of these solids at room temperature in the absence of air were identified by dissolution in aqueous solutions of MNP. The predominant reaction of OH radicals with amines and polyamines below pH 7 was the abstraction of hydrogen atoms from a carbon that is not adjacent to the protonated amino group. For agmatine and arcaine which contain guanidinium groups abstraction occurred from the α-CH. Dimethylamine was oxidized to the dimethylnitroxyl radical by H 2 O 2 in the dark. ν-Radiolysis of polyamines in the polycrystalline state generated radicals due to H-abstraction from either the α-Ch or from a carbon atom in the middle of the alkyl chain. The deamination radical was obtained from ornithine

Antioxidant multi-walled carbon nanotubes by free radical grafting of gallic acid: new materials for biomedical applications.

Science.gov (United States)

Cirillo, Giuseppe; Hampel, Silke; Klingeler, Rüdiger; Puoci, Francesco; Iemma, Francesca; Curcio, Manuela; Parisi, Ortensia Ilaria; Spizzirri, Umile Gianfranco; Picci, Nevio; Leonhardt, Albrecht; Ritschel, Manfred; Büchner, Bernd

2011-02-01

To prove the possibility of covalently functionalizing multi-walled carbon nanotubes (CNTs) by free radical grafting of gallic acid on their surface with the subsequent synthesis of materials with improved biological properties evaluated by specific in-vitro assays. Antioxidant CNTs were synthesized by radical grafting of gallic acid onto pristine CNTs. The synthesis of carbon nanotubes was carried out in a fixed-bed reactor and, after the removal of the amorphous carbon, the grafting process was performed. The obtained materials were characterized by fluorescence and Fourier transform infrared spectroscopy (FT-IR) analyses. After assessment of the biocompatibility and determination of the disposable phenolic group content, the antioxidant properties were evaluated in terms of total antioxidant activity and scavenger ability against 2,2'-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl and peroxyl radicals. Finally the inhibition activity on acetylcholinesterase was evaluated.   The covalent functionalization of CNTs with gallic acid was confirmed and the amount of gallic acid bound per g of CNTs was found to be 2.1±0.2 mg. Good antioxidant and scavenging properties were recorded in the functionalized CNTs, which were found to be able to inhibit the acetylcholinesterase with potential improved activity for biomedical and pharmaceutical applications. For the first time, a free radical grafting procedure was proposed as a synthetic approach for the covalent functionalization of CNTs with an antioxidant polyphenol. © 2010 The Authors. JPP © 2010 Royal Pharmaceutical Society.

Free radicals, oxidative stress and importance of antioxidants in human health

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K.I. Priyadarsini

2011-07-01

Full Text Available Reactive oxygen species (ROS is a collective term used for oxygen containing free radicals, depending on their reactivity and oxidizing ability. ROS participate in a variety of chemical reactions with biomolecules leading to a pathological condition known as oxidative stress. Antioxidants are employed to protect biomolecules from the damaging effects of such ROS. In the beginning, antioxidant research was mainly aimed at understanding free radical reactions of ROS with antioxidants employing biochemical assays and kinetic methods. Later on, studies began to be directed to monitor the ability of anti-oxidants to modulate cellular signaling proteins like receptors, secondary messengers, transcription factors, etc. Of late several studies have indicated that antioxidants can also have deleterious effects on human health depending on dosage and bio-availability. It is therefore, necessary to validate the utility of antioxidants in improvement of human health in order to take full advantage of their therapeutic potential.

Use of a cocktail of spin traps for fingerprinting large range of free radicals in biological systems.

Science.gov (United States)

Marchand, Valérie; Charlier, Nicolas; Verrax, Julien; Buc-Calderon, Pedro; Levêque, Philippe; Gallez, Bernard

2017-01-01

It is well established that the formation of radical species centered on various atoms is involved in the mechanism leading to the development of several diseases or to the appearance of deleterious effects of toxic molecules. The detection of free radical is possible using Electron Paramagnetic Resonance (EPR) spectroscopy and the spin trapping technique. The classical EPR spin-trapping technique can be considered as a "hypothesis-driven" approach because it requires an a priori assumption regarding the nature of the free radical in order to select the most appropriate spin-trap. We here describe a "data-driven" approach using EPR and a cocktail of spin-traps. The rationale for using this cocktail was that it would cover a wide range of biologically relevant free radicals and have a large range of hydrophilicity and lipophilicity in order to trap free radicals produced in different cellular compartments. As a proof-of-concept, we validated the ability of the system to measure a large variety of free radicals (O-, N-, C-, or S- centered) in well characterized conditions, and we illustrated the ability of the technique to unambiguously detect free radical production in cells exposed to chemicals known to be radical-mediated toxic agents.

Serum Hydroxyl Radical Scavenging Capacity as Quantified with Iron-Free Hydroxyl Radical Source

Science.gov (United States)

Endo, Nobuyuki; Oowada, Shigeru; Sueishi, Yoshimi; Shimmei, Masashi; Makino, Keisuke; Fujii, Hirotada; Kotake, Yashige

2009-01-01

We have developed a simple ESR spin trapping based method for hydroxyl (OH) radical scavenging-capacity determination, using iron-free OH radical source. Instead of the widely used Fenton reaction, a short (typically 5 seconds) in situ UV-photolysis of a dilute hydrogen peroxide aqueous solution was employed to generate reproducible amounts of OH radicals. ESR spin trapping was applied to quantify OH radicals; the decrease in the OH radical level due to the specimen’s scavenging activity was converted into the OH radical scavenging capacity (rate). The validity of the method was confirmed in pure antioxidants, and the agreement with the previous data was satisfactory. In the second half of this work, the new method was applied to the sera of chronic renal failure (CRF) patients. We show for the first time that after hemodialysis, OH radical scavenging capacity of the CRF serum was restored to the level of healthy control. This method is simple and rapid, and the low concentration hydrogen peroxide is the only chemical added to the system, that could eliminate the complexity of iron-involved Fenton reactions or the use of the pulse-radiolysis system. PMID:19794928

Antioxidant activity of lichen Cetraria aculeata

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Tomović Jovica

2016-01-01

Full Text Available The aim of the present study is to investigate the antioxidant properties of the lichen Cetraria aculeata. Antioxidant activity of the methanol and ethyl acetate extracts of lichen was tested by different methods including determination of total phenolics content, determination of total antioxidant capacity, DPPH free radical scavenging activity, inhibitory activity towards lipid peroxidation, ferrous ion chelating ability and hydroxyl radical scavenging activity. The extracts of the lichen C. aculeata showed significant antioxidant activity. The methanol extract showed higher values for total phenolics and total antioxidant capacity compared to the ethyl acetate extract, while the ethyl acetate extract demonstrated better results for DPPH radical scavenging, inhibitory activity towards lipid peroxidation, chelating ability and hydroxyl radical scavenging than the methanol extract. This is the first report of the antioxidant properties of Cetraria aculeata growing in Serbia. The results of antioxidant activity indicate the application of this lichen as source of natural antioxidants that could be used as a possible food supplement, in the pharmaceutical industry and in the treatment of various diseases.

Regenerable antioxidants-introduction of chalcogen substituents into tocopherols.

Science.gov (United States)

Poon, Jia-Fei; Singh, Vijay P; Yan, Jiajie; Engman, Lars

2015-02-02

To improve the radical-trapping capacity of the natural antioxidants, alkylthio-, alkylseleno-, and alkyltelluro groups were introduced into all vacant aromatic positions in β-, γ- and δ-tocopherol. Reaction of the tocopherols with electrophilic chalcogen reagents generated by persulfate oxidation of dialkyl dichalcogenides provided convenient but low-yielding access to many sulfur and selenium derivatives, but failed in the case of tellurium. An approach based on lithiation of the appropriate bromo-tocopherol, insertion of chalcogen into the carbon-lithium bond, air-oxidation to a dichalcogenide, and final borohydride reduction/alkylation turned out to be generally applicable to the synthesis of all chalcogen derivatives. Whereas alkylthio- and alkylseleno analogues were generally poorer quenchers of lipid peroxyl radicals than the corresponding parents, all tellurium compounds showed a substantially improved radical-trapping activity. Introduction of alkyltelluro groups into the tocopherol scaffold also caused a dramatic increase in the regenerability of the antioxidant. In a two-phase lipid peroxidation system containing N-acetylcysteine as a water-soluble co-antioxidant the inhibition time was up to six-fold higher than that recorded for the natural antioxidants. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Antioxidant Capacity, Radical Scavenging Kinetics and Phenolic ...

African Journals Online (AJOL)

Antioxidant Capacity, Radical Scavenging Kinetics and Phenolic Profile of Methanol Extracts of Wild Plants of Southern Sonora, Mexico. EF Moran-Palacio, LA Zamora-Álvarez, NA Stephens-Camacho, GA Yáñez- Farías, A Virgen-Ortiz, O Martínez-Cruz, JA Rosas-Rodríguez ...

Comparative evaluation of post-column free radical scavenging and ferric reducing antioxidant power assays for screening of antioxidants in strawberries.

Science.gov (United States)

Raudonis, Raimondas; Raudone, Lina; Jakstas, Valdas; Janulis, Valdimaras

2012-04-13

ABTS and FRAP post-column techniques evaluate the antioxidant characteristics of HPLC separated compounds with specific reagents. ABTS characterize their ability to scavenge free radicals by electron-donating antioxidants, resulting in the absorbance decrease of the chromophoric radical. FRAP - is based on the reduction of Fe(III)-tripyridyltriazine complex to Fe(II)-tripyridyltriazine at low pH by electron-donating antioxidants, resulting in an absorbance increase. Both post-column assays were evaluated and compared according to the following validation parameters: specificity, precision, limit of detection (LoD), limit of quantitation (LoQ) and linearity. ABTS and FRAP post-column assays were specific, repeatable and sensitive and thus can be used for the evaluation of antioxidant active compounds. Antioxidant active compounds were quantified according to TEAC for each assay and ABTS/FRAP ratio was derived. No previous records of antioxidative activity of leaves and fruits of strawberries (Fragaria viridis, Fragaria moschata) research have been found. The research results confirm the reliability of ABTS and FRAP post-column assays for screening of antioxidants in complex mixtures and the determination of radical scavenging and ferric reducing ability by their TEAC values. Copyright © 2012 Elsevier B.V. All rights reserved.

Total Phenolics, Flavonoids, Tannin Contents and Antioxidant Properties of Pleurotus ostreatus Cultivated on Different Wastes and Sawdust

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Ayşenur Yılmaz

2017-01-01

Full Text Available In this study, the usage possibilities of some agro-industrial wastes such as; peanut wastes, potatoes farm wastes, walnut and orange tree sawdust in Pleurotus ostreatus cultivation were investigated and total phenolic, flavonoid, condensed tannin content and antioxidant properties of these methanolic mushroom extracts were examined. For the determination of the total phenolic contents, the Folin-Ciocalteau procedure was used. The content of total flavonoid present in the methanolic extracts was measured using a spectrophotometric assay. Condensed tannins were determined according to the method by Julkunen-Tıtto. The antioxidant capacity was determined using ferric reducing antioxidant power (FRAP and free radical scavenging activity of DPPH. The highest total phenolic content (2.672 ± 0.003 mg GAE/g was found in mushroom cultivated on walnut sawdust. The highest condensed tannin (1.011 ± 0.088 CE mg/g and ferric reducing antioxidant power (FRAP (12.332 ± 0.017 μmol FeSO4.7H2O/g were observed in the same mushroom extract. The highest total flavonoid and free radical scavenging activity of DPPH were found in extract of mushroom cultivated on potatoes handle. Bioactive properties of P. ostreatus cultivated on walnut tree sawdust were generally exhibited remarkable results.

Determination of in vitro total phenolic, flavonoid contents and antioxidant capacity of the methanolic extract of Echium amoenum L.

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Fathi H

2016-06-01

Full Text Available Introduction: In traditional and modern medicine, active ingredients of medicinal plants have many applications in food, pharmaceutical, medical and industry. Antioxidants are compounds that prevent the oxidation process in the cell. Echium amoenum L. is a plant which grows in the mountainous regions of Mazandaran. This plant has different biological effects such as sedation, anti-inflammation, antidepressant and cancer preventive properties in traditional medicine. The aim of this study was to determine the total phenolic, flavonoid contents and antioxidant capacity of the methanolic extract of E.amoenum plant. Methods:In this experimental laboratory study the content of total phenolic Using the folin-siokalatio reactive at 760 nm wavelength and flavonoid With the use of aluminum chloride reagent at 420nm of E.amoenum extract were measured and antioxidant capacities of different concentrations of the extract were evaluated. Results: The results showed that total phenolic content of the extract was 429±2μg gallic acid equivalent/ml and flavonoid content was 148.56±1.52μg quercetin equivalent/ml, respectively. The radical scavenging activity by 2, 2-diphenyl-1-picryl-hydrazyl hydrate (DPPH,inhibitory concentration of 50%(IC50,was determined 178.11 μg/ml. Assessment of the reducing ability of extract showed that the extract had more activity than vitamin C. The percent nitric oxide trap inhibition of the extract was 57.89% and power iron chelating properties was 51.74%,that showed statistically significant difference in comparison with vitamin C and Quercetin (P=0.0473 and (P=0.0096 respectively. Conclusion: According to the results, E.amoenum extract had remarkable antioxidant capacity and can be proposed as an antioxidant compound used in the manufacture of food and pharmaceutical products.

Effect of Different Solvents on Total Phenolic Contents and Antioxidant Activity of Zizyphus jujube Miller Fruits

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Gholamhossein Davarynejad

2017-10-01

Full Text Available Introduction: Phenolic compounds have an ability to scavenge free radicals and cause the balance of reactive oxygen species (ROS in our body. This balance prevents atherosclerosis, coronary heart and cancer diseases. Butylated hydroxyl toluene (BHT is a well-known synthetic antioxidant, which is restricted to be used due to its probable toxic effects. Therefore, replacement of synthetic antioxidants with plant materials with high amounts of antioxidant activity, which protect the body from free radicals and many diseases caused by lipid peroxidation, is an appropriate option. ZiziphusjujubaMiller is one of the forty species belonging to Rhamnaceae family, which produces a great deal of industrial raw materials for horticultural, ornamental, food, and pharmaceutical industries. Antioxidants can be extracted by various solvents and extraction methods. Solvent extraction is the most common method used for separating natural antioxidants. Solvent properties undoubtedly play a key role in the extraction of antioxidative compounds. The type and yield of antioxidant extracted have been found to vary as affected by the solvent properties such as polarity, viscosity and vapor pressure. Therefore, it is difficult to develop a unified standard method for the extraction of antioxidants from all plant materials. Materials and Methods: Plant materials Fresh fruits were collected from Birjand, Iran, in late summer 2014. The samples were air dried under the shade at room temperature. Dried fruits were ground by using a mortar and pestle and were separately extracted by distilled water and organic solvents such as methanol, ethanol and acetone (50%, 90% and100% (v/v. After filtering through the Whatman paper #3 and removing the solvents (using a rotary evaporator (BUCHI V-850 and water (using a freeze dryer, (OPERON, FDB-5503, Korea, the dried extracts were stored in refrigerator for further analysis. Determination of Total Phenolic Content (TPC Samples were

The total antioxidant capacity and fluorescence imaging of selected plant leaves commonly consumed in Brunei Darussalam

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Watu, Aswani; Metussin, Nurzaidah; Yasin, Hartini M.; Usman, Anwar

2018-02-01

We investigated the total antioxidant capacity and fluorescence imaging of several selected plants, namely Centella asiatica, Aidia borneensis and Anacardium occidentale, which are grown and traditionally consumed in Brunei Darussalam. The total antioxidant capacities of aqueous-methanolic infusions of their leaves were measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, and microscopic fluorescence images were measured to identify the fluorescent substances bound in the leaves. We found that the total antioxidant capacity of their infusions is estimated to be 150, 25, 15 folds, respectively, lower compared with that of the standard gallic acid. Accordingly, we demonstrated that the relative antioxidant activity of young and matured leaves agrees with the intensity of red light emission of their fresh leaves upon UV excitation. Thus, this non-invasive spectroscopic method can be potentially utilized to indicate the antioxidants in plant leaves qualitatively.

Antioxidant Effects of Herbal Tea Leaves from Yacon (Smallanthus sonchifolius) on Multiple Free Radical and Reducing Power Assays, Especially on Different Superoxide Anion Radical Generation Systems.

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Sugahara, Shintaro; Ueda, Yuto; Fukuhara, Kumiko; Kamamuta, Yuki; Matsuda, Yasushi; Murata, Tatsuro; Kuroda, Yasuhiro; Kabata, Kiyotaka; Ono, Masateru; Igoshi, Keiji; Yasuda, Shin

2015-11-01

Yacon (Smallanthus sonchifolius), a native Andean plant, has been cultivated as a crop and locally used as a traditional folk medicine for the people suffering from diabetes and digestive/renal disorders. However, the medicinal properties of this plant and its processed foods have not been completely established. This study investigates the potent antioxidative effects of herbal tea leaves from yacon in different free radical models and a ferric reducing model. A hot-water extract exhibited the highest yield of total polyphenol and scavenging effect on 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical among four extracts prepared with hot water, methanol, ethanol, and ethylacetate. In addition, a higher reducing power of the hot-water extract was similarly demonstrated among these extracts. Varying concentrations of the hot-water extract resulted in different scavenging activities in four synthetic free radical models: DPPH radical (EC50 28.1 μg/mL), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical (EC50 23.7 μg/mL), galvinoxyl radical (EC50 3.06 μg/mL), and chlorpromazine cation radical (EC50 475 μg/mL). The yacon tea-leaf extract further demonstrated superoxide anion (O2(-)) radical scavenging effects in the phenazine methosulfate-NADH-nitroblue tetrazolium (EC50 64.5 μg/mL) and xanthine oxidase assay systems (EC50 20.7 μg/mL). Subsequently, incubating human neutrophilic cells in the presence of the tea-leaf extract could suppress the cellular O2(-) radical generation (IC50 65.7 μg/mL) in a phorbol 12-myristate 13-acetate-activated cell model. These results support yacon tea leaves may be a good source of natural antioxidants for preventing O2(-) radical-mediated disorders. Yacon has been considered to be a potent alternative food source for patients who require a dietary cure in regional area, while the leaf part has been provided and consumed as an herbal tea in local markets. We demonstrated here potent antioxidative effects of the tea

Solvent optimization extraction of antioxidants from foxtail millet species' insoluble fibers and their free radical scavenging properties.

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Bangoura, Mohamed Lamine; Nsor-Atindana, John; Ming, Zhou Hui

2013-11-15

In this study, water and 80% of four organic solvents were employed to optimize the extraction of antioxidants from two species of foxtail millet's insoluble fibers under the same temperature, time, and solid/solvent ratio. The results showed that the acetone was able to extract the maximum amount of antioxidants (2.32 mg/g fiber for white specie and 3.86 mg/g fiber for yellow specie) followed by methanol and propanol from both samples. The neutral and the ethanol on the other hand extracted small amount of the antioxidants from the two fiber materials. While considerable level of Total Polyphenols Content (TPC) was recorded in both the water and the organic solvents' extracts, only traces of Total Flavonoid content (TFC) were observed in water, methanol and ethanol extracts. Propanol and acetone extracts was negative to the TFC test. The potency of both white and yellow foxtail millets' insoluble fibers antioxidant extracts was investigated using five different in vitro tests. It was realized that there was a variation in their capacities to quench DPPH and ABTS(+) radicals for the time running of 0-60 min. The samples from the yellow cereal exhibited high inhibition capacity against ABTS(+). No correlation was observed between TPC and radical scavenging capacities for DPPH and ABTS(+). In general, the yellow species contained more antioxidants in comparison with the white one and this accounted for its high antioxidant activity. Copyright © 2013 Elsevier Ltd. All rights reserved.

Antioxidant activity, total phenols and flavonoids of lichens from Venezuelan Andes.

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Claudia M. Plaza

2014-10-01

Full Text Available Context:The biological potential of lichens has been documented through their use in traditional medicine. Secondary lichen metabolites exert a wide variety of biological actions, including their use as antioxidants. Aims:To evaluate the antioxidant activity, total phenol content, and flavonoids of four lichen fungal taxa collected in Mérida (Venezuela, and statistically evaluate the correlation between the antioxidant activity and the amount of phenols and flavonoids in the samples. Methods: Extracts were prepared with water, ethanol and dichloromethane from Cladonia aff. rappii, Cora aff. glabrata, Peltigera laciniata and Thamnolia vermicularis. The antioxidant capacity assessment was determined using DPPH• radical method and reducing power, with ascorbic acid as control. Total phenols were determined by means of the Folin-Ciocalteu method with gallic acid. Total flavonoids were estimated according to the modified Dowd method, using quercetin as standard. Results:The ethanolic extracts of the tested lichens showed the highest scavenging activity and reducing power compared to water and dichloromethane extracts at 4 mg/mL. The highest antiradical power value was found in ethanolic extract of Peltigera laciniata (2.28 mL/mgand the lowest in dichloromethane extract of Cora aff. glabrata (0.30 mL/mg. The correlation between antioxidant activity and total phenolic content was moderate. The flavonoids content of ethanolic extracts was highly significant but negative (p < 0.05. There was good correlation in dichloromethane extracts. The ethanolic extract of P. laciniata exhibited the highest antiradical activity despite showing the lowest flavonoid content. Conclusions: The ethanolic extracts of lichens tested showed to have the higher antioxidant activity and may be used as natural sources of new antioxidants.

Antioxidant activity and total phenolic content in Red Ginger (Zingiber officinale) based drinks

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Widayat; Cahyono, B.; Satriadi, H.; Munfarida, S.

2018-01-01

Indonesia is a rich spices country, both as a cooking spice and medicine. One of the most abundant commodities is red ginger, where it still less in application. On the other hand, the level of pollution is higher, so antioxidants are needed to protect the body cells from the bad effects of free radicals. The body can not naturally produce antioxidants as needed, so we need to consume foods with high antioxidant content. The purpose of this study is to know the antioxidant activity and total phenolic content in red ginger (Zingiber officinale) based drinks. Research design with complete randomized design (RAL) with factorial pattern 3 x 3, as the first factor is red ginger extract and water ratio (1: 1, 1: 2 and 1: 3) and second factor is the type of sugar used (cane sugar, palm sugar and mixed sugar). The results of this study indicate that red ginger extract and water ratio of 1: 3 give higher antioxidant. The highest antioxidant obtained in red ginger extract and water ratio of 1: 3 and using mixed sugar. That antioxidants value is 88.56%, it is not significant decreased compared to the antioxidant of pure ginger extract that is 91.46%. For higher phenol total content obtained on syrup that uses palm sugar. The highest phenol total content obtained in red ginger extract and water ratio of 1: 1 and using palm sugar. That total phenol content value is 6299 ppm.

Identification of mitochondrial electron transport chain-mediated NADH radical formation by EPR spin-trapping techniques.

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Matsuzaki, Satoshi; Kotake, Yashige; Humphries, Kenneth M

2011-12-20

The mitochondrial electron transport chain (ETC) is a major source of free radical production. However, due to the highly reactive nature of radical species and their short lifetimes, accurate detection and identification of these molecules in biological systems is challenging. The aim of this investigation was to determine the free radical species produced from the mitochondrial ETC by utilizing EPR spin-trapping techniques and the recently commercialized spin-trap, 5-(2,2-dimethyl-1,3-propoxycyclophosphoryl)-5-methyl-1-pyrroline N-oxide (CYPMPO). We demonstrate that this spin-trap has the preferential quality of having minimal mitochondrial toxicity at concentrations required for radical detection. In rat heart mitochondria and submitochondrial particles supplied with NADH, the major species detected under physiological pH was a carbon-centered radical adduct, indicated by markedly large hyperfine coupling constant with hydrogen (a(H) > 2.0 mT). In the presence of the ETC inhibitors, the carbon-centered radical formation was increased and exhibited NADH concentration dependency. The same carbon-centered radical could also be produced with the NAD biosynthesis precursor, nicotinamide mononucleotide, in the presence of a catalytic amount of NADH. The results support the conclusion that the observed species is a complex I derived NADH radical. The formation of the NADH radical could be blocked by hydroxyl radical scavengers but not SOD. In vitro experiments confirmed that an NADH-radical is readily formed by hydroxyl radical but not superoxide anion, further implicating hydroxyl radical as an upstream mediator of NADH radical production. These findings demonstrate the identification of a novel mitochondrial radical species with potential physiological significance and highlight the diverse mechanisms and sites of production within the ETC.

Solvent Effect on Antioxidant Activity and Total Phenolic Content of Betula alba and Convolvulus arvensi

OpenAIRE

Mohd Azman A. Nurul; Husni Shafik; Almajano P. Maria; Gallego G. Maria

2013-01-01

The potential of using herbal Betula alba (BA) and Convolvulus arvensis (CA) as a natural antioxidant for food applications were investigated. Each plant extract was prepared by using pure ethanol, different concentration of ethanol aqueous solutions, including 50% and 75%, 50% methanol aqueous and water. Total phenolic content (TPC) was determined using Folin–Ciocalteau method and antioxidant activity were analyzed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, trolox equivalent antioxida...

Free radical scavenging actions of three Trifolium species in the protection of blood plasma antioxidant capacity in vitro.

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Kolodziejczyk-Czepas, Joanna; Nowak, Pawel; Moniuszko-Szajwaj, Barbara; Kowalska, Iwona; Stochmal, Anna

2015-01-01

Three clover [Trifolium L. (Leguminosae)] species were selected on the basis of data from traditional medicine, phytochemical profiles, and agricultural significance. The in vitro evaluations of free radical scavenging properties, ferric reducing abilities, and antioxidant effects of extracts from T. pratense L. (crude extract and phenolic fraction), T. pallidum L., and T. scabrum L. (phenolic fractions) were performed. Activities of the Trifolium extracts were determined at their final concentrations of 1.5-50 µg/ml. Free radical scavenging properties of methanol extract solutions were estimated by the reduction of DPPH(•) and ABTS(•) radicals. Measurements of the total antioxidant capacity (TAC) were carried out to assess the antioxidant activities of the extracts in human blood plasma under conditions of oxidative stress, induced by 200 μM peroxynitrite. The phenolic fraction of T. pratense displayed the strongest ABTS(•) and DPPH(•) radical scavenging effects (EC50 value of 21.69 and 12.27 µg/ml, respectively). The EC50 value for T. pallidum extract attained 29.77 and 30.06 µg/ml. The two remaining extracts were less potent scavengers (EC50 value higher than 50 µg/ml). Similar differences were obtained during evaluation of the ferric reducing abilities. Analysis of antioxidant properties of the extracts in blood plasma did not provide such evident differences in their actions, however, it indicated that the T. pratense phenolic fraction displayed the strongest effect. The examined Trifolium extracts partly protected blood plasma and enhanced its non-enzymatic antioxidant defense against harmful action of peroxynitrite in vitro.

Antioxidant and Anti-Osteoporosis Activities of Chemical Constituents of the Stems of Zanthoxylum piperitum.

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Yang, Seo Young; Lee, Sang-Hyun; Tai, Bui Huu; Jang, Hae-Dong; Kim, Young Ho

2018-02-18

Two new lignans, zanthoxyloside C ( 1 ) and zanthoxyloside D ( 2 ), together with nine known compounds comprising lignans ( 3 - 5 ), flavonoids ( 6 - 8 ), and phenolics ( 9 - 11 ), were isolated from the methanol extract of the stems of Zanthoxylum piperitum. All isolates were evaluated for their antioxidant and anti-osteoporotic activities using oxygen radical absorbance capacity (ORAC), cupric reducing antioxidant capacity (CUPRAC), and tartrate-resistant acid phosphatase (TRAP) assays. Compounds 7 - 10 showed peroxyl radical-scavenging capacities and 4 , 6 - 7 , and 9 showed reducing capacities. Moreover, compounds 3 , 6 - 9 , and 11 significantly suppressed TRAP activities. These results indicated that the stems of Z. piperitum could be an excellent source for natural antioxidant and anti-osteoporosis.

Antioxidant activity and total phenolic and flavonoid content of ...

African Journals Online (AJOL)

The antioxidant capacity of the flowering aerial parts of Astragalus squarrosus was determined by 1,1- diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and ferric thiocyanate methods. The phenolic and flavonoid content was also measured. A. squarrosus showed weak free radical scavenging activity with the DPPH ...

Changes in total carbohydrate and total antioxidant activity induced by gamma irradiation of wheat flour

International Nuclear Information System (INIS)

Manupriya, B.R.; Shenoy, K. Bhasker; Patil, Shrikant L.; Somashekarappa, H.M.

2015-01-01

Wheat is a staple food grain in India after rice and occupies number one position in the world. The wheat crop not only gives food grains but also gives fodder for animals. Among many preservation methods irradiation is a current technique used to overcome infestation, contamination and spoilage of stored grains. The present study is aimed to check the changes in composition of irradiated wheat flour. Wheat flour was exposed to five different irradiation doses (0.25 KGy, 0.5KGy, 1KGy, 5KGy and 10 KGy) by using 60 Co gamma-irradiation chamber. Irradiated flour was stored in air sealed polyethylene pouch and plastic container at room temperature for different time intervals (0 th day, 1 month and 3 months). The stored flour was checked for total antioxidant activity by phosphomolybdate method and total carbohydrates concentration by phenol-sulphuric acid method. On 0 th day total antioxidant activity and total carbohydrate concentration was found to be increased at 0.5KGy (0.113 mg/ml and 0.045 mg/ml respectively) when compared to control (0.79 mg/ml and 39.5 mg/ml). Similarly for 1 month stored samples of air sealed polyethylene pouch total antioxidant activity and total carbohydrate concentration was observed to be increased at 0.5KGy (0.117 mg/ml and 0.045mg/ml respectively) when compared to control (0.096 mg/ml and 0.035 mg/ml). But in case of stored samples of plastic container total antioxidant activity increased at 0.25KGy (0.060 mg/ml) and total carbohydrate increased at 5KGy (0.051 mg/ml). Increased and decreased values were found in both factors for 3 months stored samples of air sealed polyethylene pouch and plastic container. Total antioxidant activity increased at 5KGy (0.072 mg/ml) for polyethylene bag samples and at 0.5KGy (0.137 mg/ml) for plastic container sample. Same way total carbohydrate concentration increased at 0.25KGy (0.046 mg/ml) and at 1KGy (0.045 mg/ml) respectively. This increase is due to affects of γ-irradiation on biomolecules by

Loading of free radicals on the functional graphene combined with liquid chromatography-tandem mass spectrometry screening method for the detection of radical-scavenging natural antioxidants.

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Wang, Guoying; Shi, Gaofeng; Chen, Xuefu; Chen, Fuwen; Yao, Ruixing; Wang, Zhenju

2013-11-13

A novel free radical reaction combined with liquid chromatography electrospray ionization tandem mass spectrometry (FRR-LC-PDA-ESI/APCI-MS/MS) screening method was developed for the detection and identification of radical-scavenging natural antioxidants. Functionalized graphene was prepared by chemical method for loading free radicals (superoxide radical, peroxyl radical and PAHs free radical). Separation was performed with and without a preliminary exposure of the sample to specific free radicals on the functionalized graphene, which can facilitate reaction kinetics (charge transfers) between free radicals and potential antioxidants. The difference in chromatographic peak areas is used to identify potential antioxidants. The structure of the antioxidants in one sample (Swertia chirayita) is identified using MS/MS and comparison with standards. Thirteen compounds were found to possess potential antioxidant activity, and their free radical-scavenging capacities were investigated. The thirteen compounds were identified as 1,3,5-trihydroxyxanthone-8-O-β-D-glucopyranoside (PD1), norswertianin (PD2), 1,3,5,8-tetrahydroxyxanthone (PD3), 3, 3', 4', 5, 8-penta hydroxyflavone-6-β-D-glucopyranosiduronic acid-6'-pentopyranose-7-O-glucopyranoside (PD4), 1,5,8-trihydroxy-3-methoxyxanthone (PD5), swertiamarin (PS1), 2-C-β-D-glucopyranosyl-1,3,7-trihydroxylxanthone (PS2), 1,3,7-trihydroxylxanthone-8-O-β-D-glucopyranoside (PL1), 1,3,8-trihydroxyl xanthone-5-O-β-D-glucopyranoside (PL2), 1,3,7-trihydroxy-8-methoxyxanthone (PL3), 1,2,3-trihydroxy-7,8-dimethoxyxanthone (PL4), 1,8-dihydroxy-2,6-dimethoxy xanthone (PL5) and 1,3,5,8-tetramethoxydecussatin (PL6). The reactivity and SC50 values of those compounds were investigated, respectively. PD4 showed the strongest capability for scavenging PAHs free radical; PL4 showed prominent scavenging capacities in the lipid peroxidation processes; it was found that all components in S. chirayita exhibited weak reactivity in the superoxide

Examining food additives and spices for their anti-oxidant ability to counteract oxidative damage due to chronic exposure to free radicals from environmental pollutants

Science.gov (United States)

Martinez, Raul A., III

The main objective of this work was to examine food additives and spices (from the Apiaceae family) to determine their antioxidant properties to counteract oxidative stress (damage) caused by Environmental pollutants. Environmental pollutants generate Reactive Oxygen species and Reactive Nitrogen species. Star anise essential oil showed lower antioxidant activity than extracts using DPPH scavenging. Dill Seed -- Anethum Graveolens -the monoterpene components of dill showed to activate the enzyme glutathione-S-transferase , which helped attach the antioxidant molecule glutathione to oxidized molecules that would otherwise do damage in the body. The antioxidant activity of extracts of dill was comparable with ascorbic acid, alpha-tocopherol, and quercetin in in-vitro systems. Black Cumin -- Nigella Sativa: was evaluated the method 1,1-diphenyl2-picrylhhydrazyl (DPPH) radical scavenging activity. Positive correlations were found between the total phenolic content in the black cumin extracts and their antioxidant activities. Caraway -- Carum Carvi: The antioxidant activity was evaluated by the scavenging effects of 1,1'-diphenyl-2-picrylhydrazyl (DPPH). Caraway showed strong antioxidant activity. Cumin -- Cuminum Cyminum - the major polyphenolic were extracted and separated by HPTLC. The antioxidant activity of the cumin extract was tested on 1,1'-diphenyl-2- picrylhydrazyl (DPPH) free radical scavenging. Coriander -- Coriandrum Sativum - the antioxidant and free-radical-scavenging property of the seeds was studied and also investigated whether the administration of seeds curtails oxidative stress. Coriander seed powder not only inhibited the process of Peroxidative damage, but also significantly reactivated the antioxidant enzymes and antioxidant levels. The seeds also showed scavenging activity against superoxides and hydroxyl radicals. The total polyphenolic content of the seeds was found to be 12.2 galic acid equivalents (GAE)/g while the total flavonoid content

Electrochemical and Spin-Trapping Properties of para-substituted α-Phenyl-N-tert-butyl Nitrones

International Nuclear Information System (INIS)

Rosselin, Marie; Tuccio, Béatrice; Pério, Pierre; Villamena, Frederick A.; Fabre, Paul-Louis; Durand, Grégory

2016-01-01

Nitrones are known both as therapeutic antioxidants and efficient spin-traps. In this work, the redox behavior of various para-substituted α-phenyl-N-tert-butyl nitrones (PBN) was studied by cyclic voltammetry. The polar effect of the substituents was found to correlate with the electrochemical properties of the nitronyl function. Compounds bearing an electron-withdrawing group were more easily reduced than those having an electron-donating group and an opposite trend was observed for the oxidation. Ease of oxidation was also computationally rationalized using DFT approach showing increased ease of oxidation with electron donating functionalities. Since electrochemical properties of nitrones are known to correlate with biological properties, this work provides insights in the design of potent nitrone antioxidants. Using cyclic voltammetry the relative rate of superoxide trapping by nitrones was investigated and compared to the classical antioxidant BHT. The determination of the relative rate of phenyl radical trapping was also carried out but showed no clear correlation with the nature of the substituents. This indicates the absence of a polar effect in agreement with previous data and further supports the intermediate nature, that is, non- or weakly nucleophile, of phenyl radical. On the contrary kinetics of hydroxymethyl radical trapping was found to correlate with the nature of the substituents, demonstrating the nucleophilic nature of its addition onto nitrones.

Effect of extraction solvent on total phenol content, total flavonoid content, and antioxidant activity of Limnophila aromatica

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Quy Diem Do

2014-09-01

Full Text Available Limnophila aromatica is commonly used as a spice and a medicinal herb in Southeast Asia. In this study, water and various concentrations (50%, 75%, and 100% of methanol, ethanol, and acetone in water were used as solvent in the extraction of L. aromatica. The antioxidant activity, total phenolic content, and total flavonoid content of the freeze-dried L. aromatica extracts were investigated using various in vitro assays. The extract obtained by 100% ethanol showed the highest total antioxidant activity, reducing power and DPPH (2,2-diphenyl-1-picrylhydrazyl radical scavenging activity. The same extract also exhibited the highest phenolic content (40.5 mg gallic acid equivalent/g of defatted L. aromatica and the highest flavonoid content (31.11 mg quercetin equivalent/g of defatted L. aromatica. The highest extraction yield was obtained by using 50% aqueous acetone. These results indicate that L. aromatica can be used in dietary applications with a potential to reduce oxidative stress.

Screening of various botanical extracts for antioxidant activity using DPPH free radical method.

Science.gov (United States)

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.

Antioxidant properties of a radical-scavenging peptide purified from enzymatically prepared fish skin gelatin hydrolysate.

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Mendis, Eresha; Rajapakse, Niranjan; Kim, Se-Kwon

2005-02-09

Hoki (Johnius belengerii) skin gelatin was hydrolyzed with three commercial enzymes to identify radical-scavenging potencies of derived peptides. Peptides derived from tryptic hydrolysate exhibited the highest scavenging activities on superoxide, carbon-centered 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals assessed by ESR spectroscopy. Following consecutive chromatographic separations of tryptic hydroolysate, the peptide sequence His-Gly-Pro-Leu-Gly-Pro-Leu (797 Da) acted as a strong radical scavenger under studied conditions. Further, this peptide could act as an antioxidant against linoleic acid peroxidation and the activity was closer to the highly active synthetic antioxidant butylated hydroxytoluene (BHT). In addition, antioxidative enzyme levels in cultured human hepatoma cells were increased in the presence of this peptide and it was presumed to be the peptide involved in maintaining the redox balance in the cell environment. Present data indicate that free-radical-scavenging activities of hoki skin gelatin peptides substantially contribute to their antioxidant properties measured in different oxidative systems.

Estimation of total phenolic content, cytotoxicity and in-vitro antioxidant activity of stem bark of Moringa oleifera

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Kumbhare MR

2012-04-01

Full Text Available Objective: To assess the phytochemical constituents, total phenolic content, cytotoxicity and invitro antioxidant activity of stem bark extracts of Moringa oleifera (M. oleifera (Moringaceae. Methods: Brine shrimp lethality (BSL bioassay was used to investigate the cytotoxic effects. DPPH and nitric oxide radical scavenging activity was used to demonstrate antioxidant activity. Results: Phytochemical analysis revealed the presence of tannins, flavonoids, steroids and alkaloids. The LC 50 values were obtained for extracts as 850 毺 g/mL for petroleum ether extract, 800 毺 g/mL for chloroform extract and 900 毺 g/mL for methanol extract. The total phenolic content of the methanolic extract was 50.72% w/w, equivalent to gallic acid. Petroleum ether, chloroform and methanolic extracts of M. oleifera and standard ascorbic acid were found to be scavenger of DPPH radical with an IC 50 of 124.75, 112.08, 54.34 and 13.86 毺 g/mL, respectively. Methanolic extract was found to be good scavenger of DPPH radical. Petroleum ether, chloroform, ethyl acetate soluble fraction of methanolic extracts of M. oleifera and ascorbic acid were found to be scavenger of nitric oxide radical with an IC 50 of 93.32, 65.12, 54.83 and 12.59 毺 g/mL, respectively. Ethyl acetate soluble fraction was found to be good scavenger of nitric oxide radical. Conclusions: It can be concluded that the crude extracts of M. oleifera is a potential source of natural antioxidants, and this justifies its uses in folkloric medicines.

Potential Use of Spin Traps to Control ROS in Antipollution Cosmetics—A Review

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Prashant D. Sawant

2018-01-01

Full Text Available Pollution from air and sunlight has adverse effects on human health, particularly skin health. It creates oxidative stress, which results in skin diseases, including skin cancer and aging. Different types of antioxidants are used as preventative actives in skin-care products. However, they have some limitations as they also scavenge oxygen. Recently, spin traps are being explored to trap free radicals before these radicals generating more free radicals (cascading effect and not the oxygen molecules. However, not all spin traps can be used in the topical cosmetic skin-care products due to their toxicity and regulatory issues. The present review focuses on the different pathways of reactive oxygen species (ROS generation due to pollution and the potential use of spin traps in anti-pollution cosmetics to control ROS.

Total polyphenolic contents and in vitro antioxidant properties of eight Sida species from Western Ghats, India.

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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.

Spin trapping study on the nature of radicals generated by X radiolysis and peroxidation of linolenic acid

International Nuclear Information System (INIS)

Azizova, O.A.; Osipov, A.N.; Zubarev, V.E.; Yakhyaev, A.V.; Vladimirov, Yu.A.; Savov, V.M.; Kagan, V.E.

1983-01-01

The radicals of linolenic acid and their spin adducts (SA) with PBN formed during X radiolysis of linolenic acid and in lipid peroxidation with ferrous ions were investigated and identified. It was found that in the absence of oxygen in pure linolenic acid at 77 K X irradiation produces alkyl and carboxyl radicals. In the presence of the spin trap alkyl radical spin adducts were formed. Irradiation of linolenic acid in the presence of oxygen at 77 K also resulted in the formation of alkyl radicals. These radicals were transformed into peroxy radicals in the interaction of alkyl radical with oxygen upon heating to 117 K. In the presence of spin trap X irradiation of linolenic acid and heating of the sample up to 300 K gave rise to EPR spectra of SA alkyl and unidentified radicals. Lipid peroxidation of linolenic acid induced by ferrous ions in the presence of spin trap also formed radicals and SA of linolenic acid. The spectral parameters of SA generated with ferrous ions in lipid peroxidation and of those generated during X radiolysis do not differ. The similarity of spectral parameters of SA in these two cases suggests a similarity in the structure of linolenic acid radicals. (author)

Antioxidant activity and total phenolic content of Moringa oleifera leaves in two stages of maturity.

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Sreelatha, S; Padma, P R

2009-12-01

Antioxidants play an important role in inhibiting and scavenging free radicals, thus providing protection to human against infections and degenerative diseases. Current research is now directed towards natural antioxidants originated from plants due to safe therapeutics. Moringa oleifera is used in Indian traditional medicine for a wide range of various ailments. To understand the mechanism of pharmacological actions, antioxidant properties of the Moringa oleifera leaf extracts were tested in two stages of maturity using standard in vitro models. The successive aqueous extract of Moringa oleifera exhibited strong scavenging effect on 2, 2-diphenyl-2-picryl hydrazyl (DPPH) free radical, superoxide, nitric oxide radical and inhibition of lipid per oxidation. The free radical scavenging effect of Moringa oleifera leaf extract was comparable with that of the reference antioxidants. The data obtained in the present study suggests that the extracts of Moringa oleifera both mature and tender leaves have potent antioxidant activity against free radicals, prevent oxidative damage to major biomolecules and afford significant protection against oxidative damage.

Antioxidant and Free Radical Scavenging Capacity of Seed and Shell Essential Oils Extracted from Abrus precatorius (L

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Sunday O. Okoh

2014-04-01

Full Text Available Essential oils from plants have been proven safe as natural antioxidants, and few are already marketed as digestive enhancers as well as in prevention of several degenerative diseases. This study evaluated the antioxidant capacity of seed and shell essential oils of Abrus precatorius (L, a herb used for ethno-medicinal practices in Nigeria. The essential oils were obtained by hydro-distillation. The ability of the oils to act as hydrogen/electrons donor or scavenger of radicals were determined by in-vitro antioxidant assays using 2,2-diphenyl-2-picryl-hydrazyl free radical (DPPH. scavenging; 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS radical scavenging; lipid peroxide and nitric oxide radicals scavenging assays. The IC50 of the seed and shell oils (2.10 mg/mL and 1.20 mg/mL respectively showed that antioxidant activity is higher than that for the standard drugs (3.20 mg/mL and 3.40 mg/mL for the nitric oxide scavenging assay. The lipid peroxidation radical activity of the oils were similar to vitamin C, weak DPPH and ABTS radical scavenging activities were discovered in comparison to vitamin C and rutin. Generally, in the four antioxidant assays, a significant correlation existed between concentrations of the oils and percentage inhibition of free radicals and lipid peroxidation. The composition of A. precatorius essential oils reported earlier may account for their antioxidant capacity.

Evaluation of Both Free Radical Scavenging Capacity and Antioxidative Damage Effect of Polydatin.

Science.gov (United States)

Jin, Ju; Li, Yan; Zhang, Xiuli; Chen, Tongsheng; Wang, Yifei; Wang, Zhiping

Cellular damage such as oxidation and lipid peroxidation, and DNA damage induced by free-radicals like reactive oxygen species, has been implicated in several diseases. Radicals generated by 2,2-azobis (2-amidino-propane) dihydrochloride (AAPH) are similar to physiologically active ones. In this study we found that polydatin, a resveratrol natural precursor derived from many sources, has the capacity of free radical scavenging and antioxidative damage. Using free radical scavenging assays, the IC50 values of polydatin were 19.25 and 5.29 μg/ml with the DPPH and the ABTS assay, respectively, and 0.125 mg ferrous sulfate/1 mg polydatin with the FRAP assay. With the AAPH-induced oxidative injury cell model assay, polydatin showed a strong protective effect against the human liver tumor HepG2 cell oxidative stress damage. These results indicate that the antioxidant properties of polydatin have great potential for use as an alternative to more toxic synthetic antioxidants as an additive in food, cosmetics and pharmaceutical preparations for the treatment of oxidative diseases.

Characterization of dietary constituents and antioxidant capacity of Tropaeolum pentaphyllum Lam.

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De Bona, Gicele S; Boschetti, Wiliam; Bortolin, Rafael C; Vale, Maria G R; Moreira, José C F; de Rios, Alessandro O; Flôres, Simone H

2017-10-01

The aim of this study was to evaluate the nutritional content and antioxidant capacity of the tubers, leaves and, flowers of the species Tropaeolum pentaphyllum Lam. The three parts of the plant were analyzed by physicochemical methods, atomic absorption spectrometry, spectrophotometric and chromatographic techniques. The tubers, leaves, and flowers exhibited significant differences in all parameters evaluated. The leaves showed significantly higher values of protein (16.28 ± 0.02 g/100 g), total dietary fiber (27.78 ± 0.15 g/100 g) and quercetin (3798.61 ± 37.57 µg/g) when compared to the tubers and flowers. The study revealed a potential content of the protein, dietary fiber, and flavonoids the species Tropaeolum pentaphyllum , when compared with the sweet potatoes leaves ( Ipomoea batatas L.). In addition, the antioxidant activities of leaves and flowers were also higher measured by ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), DPPH (2,2-diphenyl-1-picrylhydrazyl), and TRAP (total radical-trapping antioxidant potential) methods. Tropaeolum pentaphyllum have high nutritional potential that can be exploited to improve nutritional value of various food products.

Effect of cold storage on total phenolics content, antioxidant activity and vitamin C level of selected potato clones.

Science.gov (United States)

Külen, Oktay; Stushnoff, Cecil; Holm, David G

2013-08-15

Twelve Colorado-grown specialty potato clones were evaluated for total phenolic content, antioxidant activity and ascorbic acid content at harvest and after 2, 4, 6 and 7 months cold storage at 4 °C. Potato clones were categorized as pigmented ('CO97226-2R/R', 'CO99364-3R/R', 'CO97215-2P/P', 'CO97216-3P/P', 'CO97227-2P/P', 'CO97222-1R/R', 'Purple Majesty', 'Mountain Rose' and 'All Blue'), yellow ('Yukon Gold') and white fleshed ('Russet Nugget', 'Russet Burbank'). Folin-Ciocalteu reagent was used to estimate total phenolic content, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS(•+) ) and 2,2-diphenyl-1-picrylhydrazyl (DPPH(•) ) radical scavenging assays were used to estimate antioxidant capacity. Pigmented potato genotypes had significantly higher total phenolic content and antioxidant activity at all data points than yellow- and white-fleshed cultivars. Vitamin C content was higher in 'Yukon Gold' than in the other clones. The highest level of vitamin C in all clones was at harvest and after 2 months in cold storage. Vitamin C content in all potato clones dropped rapidly with longer intervals of cold storage. Although total phenolic content and antioxidant activity fluctuated during cold storage, after 7 months of cold storage their levels were slightly higher than at harvest. Total phenolic content was better correlated with Trolox equivalent antioxidant capacity (TEAC)/ABTS(•+) than the TEAC/DPPH(•) radical scavenging assay. Pigmented potato clones had significantly higher total phenolic content and antioxidant activity, while the yellow-fleshed potato cultivar 'Yukon Gold' had significantly higher vitamin C content. Vitamin C content decreased in all potato clones during cold storage, while total phenolics increased in pigmented clones. © 2013 Society of Chemical Industry.

Reactions of linoleic acid peroxyl radicals with phenolic antioxidants: a pulse radiolysis study

International Nuclear Information System (INIS)

Erben-Russ, Michael; Bors, Wolf; Saran, Manfred

1987-01-01

Linoleic acid peroxyl radicals (LOO) can be viewed as model intermediates occurring during lipid peroxidation processes. Formation and reactions of these species were investigated in aqueous alkaline solution using pulse radiolysis combined with kinetic spectroscopy. Irradiation of linoleic acid in N 2 O/O 2 -saturated solutions leads to a mixture of peroxyl radical isomers; reaction of 13-hydroperoxylinoleic acid (13-LOOH) with azide radicals in N 2 O-saturated solution produces 13-LOO radicals specifically. These peroxyl radicals cannot be observed directly, but their reactions with kaempferol and quercetin, acting as radical-scavenging antioxidants, produced strongly absorbing aroxyl radicals (ArO). The same aroxyl radicals were generated by OH and N 3 with rate constants exceeding 10 9 dm 3 mol -1 s -1 . Applying a reaction scheme that includes competing generation and decay reactions of both LOO and ArO radicals, individual rate constants were derived for LOO reactions with the phenols (> 10 7 dm 3 mol -1 s-? 1 ), with aroxyl radicals to form covalent adducts (> 10 8 dm 3 mol -1 s -1 ), as well as for their bimilecular decay (3.0 x 10 8 dm 3 mol -1 s -1 ). These results demonstrate high reactivity of fatty acid peroxyl radicals and flavone antioxidants in aqueous solution. (author)

Antioxidant and Anti-Osteoporosis Activities of Chemical Constituents of the Stems of Zanthoxylum piperitum

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Seo Young Yang

2018-02-01

Full Text Available Two new lignans, zanthoxyloside C (1 and zanthoxyloside D (2, together with nine known compounds comprising lignans (3–5, flavonoids (6–8, and phenolics (9–11, were isolated from the methanol extract of the stems of Zanthoxylum piperitum. All isolates were evaluated for their antioxidant and anti-osteoporotic activities using oxygen radical absorbance capacity (ORAC, cupric reducing antioxidant capacity (CUPRAC, and tartrate-resistant acid phosphatase (TRAP assays. Compounds 7–10 showed peroxyl radical-scavenging capacities and 4, 6–7, and 9 showed reducing capacities. Moreover, compounds 3, 6–9, and 11 significantly suppressed TRAP activities. These results indicated that the stems of Z. piperitum could be an excellent source for natural antioxidant and anti-osteoporosis.

Evidence of free radical and antioxidant activity in Spirodela exposed to metallic and metal oxide nanoparticles: potential for protein and lipid damage

CSIR Research Space (South Africa)

Thwala, Melusi

2012-04-01

Full Text Available the quantities of free radicals (H202, total ROS/RNS), antioxidant activity (catalase, superoxide disrnutasc, and total antioxidam capacity) were analyzed. Oxidative stress has been suggested as a significant route of toxicity induction by engineered...

The ability of Abelmoschus manihot L. leaf extract in scavenging of free radical DPPH and total flavonoid determination

Science.gov (United States)

Sudewi, S.; Lolo, W. A.; Warongan, M.; Rifai, Y.; Rante, H.

2017-11-01

Abelmoschus manihot L. has reported to have flavonoids content. This study aims were to determine the ability of A. manihot extract in counteracting free radical DPPH and determine the content of total flavonoids. A. manihot leaf was taken from 2 regions in North Sulawesi, namely Tomohon and Kotamobagu. The maceration was carried out to extract the active compound in a 96% ethanol solvent. Free radical scavenging analysis was carried out by DPPH and determination of its total flavonoid in the extract was measured using spectrophotometri method. The results showed that A. manihot extract from Tomohon and Kotamobagu could counteract free radical of DPPH with value of free radical activity of 88.151 and 88.801 %, respectively. A. manihot leaf from Kotamobagu has higher total flavonoids content 61.763 mg/g compare to Tomohon 46.679 mg/g which presented as quercetin. A. manihot has antioxidant activity.

Evaluation of In Vitro Antioxidant Potential of Cordia retusa.

Science.gov (United States)

Amudha, Murugesan; Rani, Shanmugam

2016-01-01

The present study was carried out to investigate the antioxidant potential, total flavonoid and phenolic content in extracts of aerial parts of Cordia retua (Vahl.) Masam. The samples such as ethyl acetate and ethanol extracts were tested using six in vitro models such as 2,2-diphenyl-1-picrylhydrazyl, nitric oxide radical, iron chelating, hydroxyl radical, superoxide radical scavenging activity and total antioxidant activity to evaluate the in vitro antioxidant potential of C. retusa by spectrophotometrically. Total flavonoid and phenolic content in samples were estimated using aluminum chloride colorimetric and Folin-Ciocalteu method. The results were analyzed statistically by the regression method. Half maximal inhibitory concentration (IC50) of the ethanol extract was found to be 596 μg/ml for DPPH, 597 μg/ml for nitric oxide radical, 554 μg/ml for iron chelating, 580 μg/ml for hydroxyl radical, 562 μg/ml for superoxide radical and 566 μg/ml for total antioxidant capacity. Furthermore, the total flavonoid content and total phenolic content of the ethanol extract were found to be 2.71 mg gallic acid equivalent per gram of extract and 1.86 mg quercetin equivalent per gram of extract, respectively. In all the testing, a significant correlation existed between concentrations of the extract and percentage inhibition of free radicals. The results of the present comprehensive analysis demonstrated that C. retusa possess potent antioxidant activity, high flavonoid and phenolic content. The antioxidant property may be related to the polyphenols and flavonoids present in the extract. These results clearly indicated that C. retusa is effective against free radical mediated diseases as a natural antioxidant.

Evaluation of In Vitro Antioxidant Potential of Cordia retusa

Science.gov (United States)

Amudha, Murugesan; Rani, Shanmugam

2016-01-01

The present study was carried out to investigate the antioxidant potential, total flavonoid and phenolic content in extracts of aerial parts of Cordia retua (Vahl.) Masam. The samples such as ethyl acetate and ethanol extracts were tested using six in vitro models such as 2,2-diphenyl-1-picrylhydrazyl, nitric oxide radical, iron chelating, hydroxyl radical, superoxide radical scavenging activity and total antioxidant activity to evaluate the in vitro antioxidant potential of C. retusa by spectrophotometrically. Total flavonoid and phenolic content in samples were estimated using aluminum chloride colorimetric and Folin-Ciocalteu method. The results were analyzed statistically by the regression method. Half maximal inhibitory concentration (IC50) of the ethanol extract was found to be 596 μg/ml for DPPH, 597 μg/ml for nitric oxide radical, 554 μg/ml for iron chelating, 580 μg/ml for hydroxyl radical, 562 μg/ml for superoxide radical and 566 μg/ml for total antioxidant capacity. Furthermore, the total flavonoid content and total phenolic content of the ethanol extract were found to be 2.71 mg gallic acid equivalent per gram of extract and 1.86 mg quercetin equivalent per gram of extract, respectively. In all the testing, a significant correlation existed between concentrations of the extract and percentage inhibition of free radicals. The results of the present comprehensive analysis demonstrated that C. retusa possess potent antioxidant activity, high flavonoid and phenolic content. The antioxidant property may be related to the polyphenols and flavonoids present in the extract. These results clearly indicated that C. retusa is effective against free radical mediated diseases as a natural antioxidant. PMID:27168685

N-tert-butylmethanimine N-oxide is an efficient spin-trapping probe for EPR analysis of glutathione thiyl radical

Science.gov (United States)

Scott, Melanie J.; Billiar, Timothy R.; Stoyanovsky, Detcho A.

2016-01-01

The electron spin resonance (EPR) spin-trapping technique allows detection of radical species with nanosecond half-lives. This technique is based on the high rates of addition of radicals to nitrones or nitroso compounds (spin traps; STs). The paramagnetic nitroxides (spin-adducts) formed as a result of reactions between STs and radical species are relatively stable compounds whose EPR spectra represent “structural fingerprints” of the parent radical species. Herein we report a novel protocol for the synthesis of N-tert-butylmethanimine N-oxide (EBN), which is the simplest nitrone containing an α-H and a tertiary α′-C atom. We present EPR spin-trapping proof that: (i) EBN is an efficient probe for the analysis of glutathione thiyl radical (GS•); (ii) β-cyclodextrins increase the kinetic stability of the spin-adduct EBN/•SG; and (iii) in aqueous solutions, EBN does not react with superoxide anion radical (O2−•) to form EBN/•OOH to any significant extent. The data presented complement previous studies within the context of synthetic accessibility to EBN and efficient spin-trapping analysis of GS•. PMID:27941944

Test for antioxidant ability by scavenging long-lived mutagenic radicals in mammalian cells and by blood test with intentional radicals: an application of gallic acid

International Nuclear Information System (INIS)

Kumagai, Jun; Kawaura, Tomoko; Miyazaki, Tetsuo; Prost, Michel; Prost, Emmanuelle; Watanabe, Masami; Quetin-Leclercq, J.Joeelle

2003-01-01

Antioxidant ability of gallic acid (GA) are determined both by electron spin resonance measurement of long-lived radicals produced in γ-ray irradiated Syrian golden hamster embryo cells with GA and by hemolysis measurement with GA when blood cells are submitted to radicals. Scavenging properties of GA are determined by the reaction rate constant with long-lived mutagenic radicals in the cells while the blood test allows to analyze the global effects of this compound: radical scavenger+metal ion chelator+regeneration of intra- and extra-cellular antioxidant

Development of an HPLC post-column antioxidant assay for Solidago canadensis radical scavengers.

Science.gov (United States)

Marksa, Mindaugas; Radušienė, Jolita; Jakštas, Valdas; Ivanauskas, Liudas; Marksienė, Rūta

2016-01-01

The aim of this work was to modify and validate the post-column high-performance liquid chromatography (HPLC)-ABTS and DPPH methods for evaluating the antioxidant activity of the methanolic extracts of Solidago canadensis (Canadian goldenrod) leaves and flowers. Separation of the analytes was performed via the HPLC-PDA method on a YMC analytical column using a gradient elution program. Three compounds with antioxidant properties - chlorogenic acid, rutin and isoquercitrin - and two unidentified antioxidants were established. The research showed that the coil temperature regimes and loop length combinations influence the optimised post-column assay method for detecting the antioxidant activity of goldenrod radical scavengers. Investigations established that the temperature in the reaction coil was a substantial factor contributing to the signal strength of the analytes after reacting with the DPPH and ABTS radicals.

An EPR spin-probe and spin-trap study of the free radicals produced by plant plasma membranes

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GORAN BACIC

2005-02-01

Full Text Available Plant plasma membranes are known to produce superoxide radicals, while the production of hydroxyl radical is thought to occur only in the cell wall. In this work it was demonstrated using combined spin-trap and spin-probe EPR spectroscopic techniques, that plant plasma membranes do produce superoxide and hydroxyl radicals but by kinetically different mechanisms. The results show that superoxide and hydroxyl radicals can be detected by DMPO spin-trap and that the mechanisms and location of their production can be differentiated using the reduction of spin-probes Tempone and 7-DS. It was shown that the mechanism of production of oxygen reactive species is NADH dependent and diphenylene iodonium inhibited. The kinetics of the reduction of Tempone, combined with scavengers or the absence of NADH indicates that hydroxyl radicals are produced by a mechanism independent of that of superoxide production. It was shown that a combination of the spin-probe and spin-trap technique can be used in free radical studies of biological systems, with a number of advantages inherent to them.

Leghemoglobin-derived radicals. Evidence for multiple protein-derived radicals and the initiation of peribacteroid membrane damage

DEFF Research Database (Denmark)

Moreau, S; Davies, Michael Jonathan; Mathieu, C

1996-01-01

, with the consequent generation of lipid-derived radicals. The formation of such radicals may result in the depletion of membrane antioxidants and the initiation of lipid peroxidation. This transfer of damage from the heme center via the protein surface to neighboring membranes may be of considerable biological......-derived phenoxyl radical present at Tyr-133 in the soybean protein and Tyr-138 in the lupin protein. To obtain further information on these protein radicals and their potential interaction with the physiologically important peribacteroid membrane (which surrounds the microsymbiont in vivo), EPR spin trapping......); these radicals may be side chain- or alpha-carbon-derived, their exact sites have not been determined. Some of these radicals are on the protein surface and may be key intermediates in the formation of protein dimers. These radicals have been shown to be capable of reacting with peribacteroid membrane fractions...

Antioxidant, Cytotoxic Activities and Total Phenolic Content of Four Indonesian Medicinal Plants

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Waras Nurcholis

2017-03-01

Full Text Available The crude ethanol extracts of four Indonesian medicinal plants namely Curcuma xanthorrhiza Roxb.,Phyllanthus niruri Linn., Andrographis paniculata Ness., and Curcuma aeruginosa Roxb. wereexamined for their antioxidant (radical scavenging activity using 2, 2-diphenyl-2-picrylhydrazyl(DPPH free radical and cytotoxicity using brine shrimp lethality test (BSLT. The total phenoliccontent was used the Folin-Ciocalteu method. IC50 values for DPPH radical scavenging activityranged from 14.5 to 178.5 μg/ml, with P. niruri having the lowest value and therefore the mostpotent, and C. aeruginosa having the highest value. LC50 values for BSLT ranged from 210.3 to593.2 μg/ml, with C. xanthorrhiza and A. paniculata having the lowest and highest values,respectively. The total phenolic content of the Indonesian plants ranged from 133.0 ±3.7 to863.3±54.7 mg tannic acid equivalent per 1 g extract, with C. aeruginosa and P. niruri having thelowest and highest values, respectively. A positive correlation between free radical scavengingactivity and the content of phenolic compounds was found in the four of Indonesian medicinal plants.

[The significance of free radicals and antioxidants due to the load induced by sport activity].

Science.gov (United States)

Holecek, V; Liska, J; Racek, J; Rokyta, R

2004-01-01

Sport performance is followed by a high production of free radicals. The main reasons are reperfusion after the previous imbalance between the increased need of the organism and the ability of blood supply by oxygen, increased production of ATP, decomposition of the cells particularly white blood cells, oxidation of the purin basis from DNA, stress, output of epinephrine release of free iron, increased temperature in the muscle and its inflammation, and the reception of free radicals from external environment. Peroxidation of lipids, proteins, DNA and other compounds follows the previous biochemical steps. Antioxidants are consumed by free radicals, antioxidative enzymes are released into blood plasma, intracellular calcium is increased, the production of nitric oxide rises, the levels of hydrogen peroxide and hypochlorous acid increase. These penetrate through the membranes and oxidatively damage the tissues. Training improves the ability of the organism to balance the increased load of free radicals. The damage can be lowered by the application of a mixture of antioxidants, the most important are vitamin C, A, E, glutathione, selenium, carnosine, eventually bioflavonoids and ginkgo biloba. The lack of antioxidants can significantly diminish the sport performance and therefore the supplementation with antioxidants is for top sportsmen but also for aged people advisable.

Reactions of linoleic acid peroxyl radicals with phenolic antioxidants: a pulse radiolysis study

Energy Technology Data Exchange (ETDEWEB)

Erben-Russ, M.; Bors, W.; Saran, M.

1987-09-01

Linoleic acid peroxyl radicals (LOO) can be viewed as model intermediates occurring during lipid peroxidation processes. Formation and reactions of these species were investigated in aqueous alkaline solution using pulse radiolysis combined with kinetic spectroscopy. Irradiation of linoleic acid in N/sub 2/O/O/sub 2/-saturated solutions leads to a mixture of peroxyl radical isomers; reaction of 13-hydroperoxylinoleic acid (13-LOOH) with azide radicals in N/sub 2/O-saturated solution produces 13-LOO radicals specifically. These peroxyl radicals cannot be observed directly, but their reactions with kaempferol and quercetin, acting as radical-scavenging antioxidants, produced strongly absorbing aroxyl radicals (ArO). The same aroxyl radicals were generated by OH and N/sub 3/ with rate constants exceeding 10/sup 9/ dm/sup 3/ mol/sup -1/ s/sup -1/. Applying a reaction scheme that includes competing generation and decay reactions of both LOO and ArO radicals, individual rate constants were derived for LOO reactions with the phenols (> 10/sup 7/ dm/sup 3/ mol/sup -1/ s-./sup 1/), with aroxyl radicals to form covalent adducts (> 10/sup 8/ dm/sup 3/ mol/sup -1/ s/sup -1/), as well as for their bimilecular decay (3.0 x 10/sup 8/ dm/sup 3/ mol/sup -1/ s/sup -1/). These results demonstrate high reactivity of fatty acid peroxyl radicals and flavone antioxidants in aqueous solution.

Analytical profiling of selected antioxidants and total antioxidant capacity of goji (Lycium spp.) berries.

Science.gov (United States)

Protti, Michele; Gualandi, Isacco; Mandrioli, Roberto; Zappoli, Sergio; Tonelli, Domenica; Mercolini, Laura

2017-09-05

Goji berries and derived products represent a relevant source of micronutrients, most of which are natural antioxidants and contribute to the high nutritional quality of these fruits. Three brands of dried goji berries have been analysed by a multidisciplinary approach to get an insight into both their content of selected antioxidants and their antioxidant capacity (AC). The former goal has been achieved by developing a liquid chromatographic method coupled to mass spectrometry and combined to a fast solid phase extraction. Several significant representative antioxidant compounds belonging to the following classes: flavonoids, flavan-3-ols, phenolic acids, amino acids and derivatives, and carotenoids have been taken into account. Quercetin and rutin were found to be the predominant flavonoids, chlorogenic acid was the most abundant phenolic acid and zeaxanthin was the major carotenoid. The AC of the goji berries has been evaluated by four analytical methods in order to estimate the contributions of different reactions involved in radicals scavenging. In particular, AC has been determined using 3 standardised methods (DPPH, ABTS, ORAC) and a recently proposed electrochemical method, which measures the scavenging activity of antioxidants towards OH radicals generated both by hydrogen peroxide photolysis and the Fenton reaction. The results obtained from chemical composition and antioxidant capacity assays confirm the high nutritional and commercial value of goji berries and highlight that the three brands do not exhibit significant differences. Copyright © 2017 Elsevier B.V. All rights reserved.

The influence of gamma-irradiation on the formation of free radicals and antioxidant status of oregano (Origanum vulgare L.)

Energy Technology Data Exchange (ETDEWEB)

Horváthov Á, J.; Suhaj, M.; Polovka, M.; Šimko, P. [Food Research Institute, Bratislava (Slovakia); Brezov á, V. [Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava (Slovakia)

2007-05-15

The influence of various gamma-radiation dose absorptions on oregano samples was monitored by means of electron paramagnetic resonance (EPR) spectroscopy. Further, the antioxidant activity of oregano methanol/water extracts was characterised using 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH), thiobarbituric acid reactive substances (TBARS), ferric reducing power (FRP), and total content of phenolic compounds (TPC) assays. EPR spectroscopy was used for the investigation of the influence of the absorbed dose on the character of the paramagnetic structures formed, as well as for their thermal stability and life-time characterisation. Paramagnetic structures of different origin (mostly of cellulose and carbohydrate), possessing diverse thermal stability and life-time, were identified in the gamma-irradiated samples. Immediately after irradiation, a statistically significant increase of the TBARS values and the total content of phenolic compounds in methanol/water oregano extract was observed. The alterations of the antioxidant properties of oregano extracts with the time after the radiation treatment were also monitored. A substantial time-dependent decrease of antioxidant activity was observed, probably as a result of storage, with both irradiated and non-irradiated oregano samples, as obvious from the ferric reducing power test and the content of total phenolic substances. The influence of irradiation and subsequent storage on the DPPH radical-scavenging ability was negligible.

Comparative study of the anti-oxidant activity of the total polyphenols extracted from Hibiscus Sabdariffa L., Glycine max L. Merr., yellow tea and red wine through reaction with DPPH free radicals

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T. Andzi Barhé

2016-01-01

Full Text Available The present study is part of the evaluation of extracts of Glycine max L. Merr and Hibiscus L. Sabdariffa as antioxidants. A comparative study was performed with extracts of yellow tea and commercial red wine, two foods known for their antioxidant activity. The method applied is free radical scavenging using the 1,1-diphenyl-2-picrylhydrazyl (DPPH°. The antioxidant properties were identified and measured by the determining the anti-radical activity reducing index, expressed in percentage % RSA (Radical Scavenger Activity, and by the determination of the colouring intensity (IC50. All results are compared to those of ascorbic acid as reference antioxidant. The results indicate the following order for the antioxidant power of the extracts tested. % RSA (tea > % RSA (Glycine max % > RSA (red wine % > RSA (Sabdariffa Hibiscus, and colouring intensities (IC50 ranging from 4.62 μM (ascorbic acid to 1.10 μM (Hibiscus sabdariffa correlated with their chemical structure and the content of phenolic compounds.

Total phenolic content, antioxidant and antimicrobial activity of Equisetum arvense L.

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Kukrić Zoran

2013-01-01

Full Text Available The antioxidant and antimicrobial activity of Equisetum arvense L. harvested in a polluted urban area were investigated. The total phenolic content determined by a modified Folin-Ciocalteu method was 335.8 mg of GEA/g of the dried ethanol extract. Antioxidant activity determined by FRAP method was 28.7 mM Fe(II/g of extract, whereas antioxidant activity index for stable DPPH free radicals was 3.86. The results were compared with control antioxidants (gallic acid, vitamin C, BHA and BHT. Antimicrobial activity was tested by monitoring the impact of different extract concentrations through measuring the change in optical density of bacterial suspension over time and by determining MIC and MBC using macrodilution method. E. arvense extract has been effective on the tested microorganisms depending on the concentration and exposure time. The extract had the strongest antibacterial activity on Staphylococcus aureus, with MIC and MBC of 11.14 mg/mL and 22.28 mg/mL respectively, and the weakest effect on Bacillus cereus, with MIC of 89.10 mg/mL.

Measurement of the total antioxidant response in preeclampsia with a novel automated method.

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Harma, Mehmet; Harma, Muge; Erel, Ozcan

2005-01-10

Preeclampsia is one of the most serious complications of pregnancy. Free radical damage has been implicated in the pathophysiology of this condition. In this study, we aimed to measure the antioxidant capacity in plasma samples from normotensive and preeclamptic pregnant women to evaluate their antioxidant status using a more recently developed automated measurement method. Our study group contained 42 women, 24 of whom had preeclampsia, while 18 had normotensive pregnancies. We measured the total plasma antioxidant capacity for all patients, as well as the levels of four major individual plasma antioxidant components; albumin, uric acid, ascorbic acid and bilirubin, and as a reciprocal measure, their total plasma peroxide levels. Statistically significant differences (determined using Student's t-test) were noted between the normotensive and the preeclamptic groups for their total antioxidant responses and their vitamin C levels (1.31 +/- 0.12 mmol versus 1.06 +/- 0.41 mmol Trolox eq./L; 30.2 +/- 17.83 micromol/L versus 18.1 +/- 11.37 micromol/L, respectively), which were both considerably reduced in the preeclamptic patients. In contrast, the total plasma peroxide levels were significantly elevated in this group (49.8 +/- 14.3 micromol/L versus 38.8 +/- 9.6 micromol/L). We found a decreased total antioxidant response in preeclamptic patients using a simple, rapid and reliable automated colorimetric assay, which may suitable for use in any routine clinical biochemistry laboratory, and considerably facilitates the assessment of this useful clinical parameter. We suggest that this novel method may be used as a routine test to evaluate and follow up of the levels of oxidative stress in preeclampsia.

Evaluation of free radical scavenging capacity and antioxidative damage effect of resveratrol-nanostructured lipid carriers

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Jin, Ju; Shi, Fan; Li, Qiu-wen; Li, Pei-shan; Chen, Tong-sheng; Wang, Yi-fei; Wang, Zhi-ping

2016-03-01

Cellular damage induced by free-radicals like reactive oxygen species has been implicated in several diseases. 2, 2-azobis(2-amidino-propane) dihydrochloride(AAPH) generates two potent ROS capable of inducing lipid peroxidation: alkoxy radical(RO-) and peroxy radical(ROO-). These radicals are similar to those that are physiologically active and thus might initiate a cascade of intracellular toxic events leading to oxidation, lipid peroxidation, DNA damage and subsequent cell death. Hence naturally anti-oxidant play a vital role in combating these conditions. In this study, resveratrol loaded nanostructured lipid carriers (Res-NLC) was prepared by hot melting and then high pressure homogenization technique. The effects of Res-NLC on free radical scavenging capacity and antioxidative damage is investigated. The particle size and zeta potential of Res-NLC were 139.3 ± 1.7 nm and -11.21 ± 0.41 mV, respectively. By free radical scavenging assays, the IC50 value of Res-NLC were 19.25, 5.29 μg/mL with DPPH, ABTS assay respectively, and 0.161 mg ferrous sulfate/1 mg Res-NLC with FRAP assay; and by AAPH-induced oxidative injury cell model assay, Res-NLC showed the strong protective effect against the human liver tumor HepG2 cell oxidative stress damage. These results indicated that the antioxidant properties of Res-NLC hold great potential used as an alternative to more toxic synthetic antioxidants as an additive in food, cosmetic and pharmaceutical preparations for the oxidative diseases treatment.

The role of free radicals and antioxidants in reproduction.

Science.gov (United States)

Agarwal, Ashok; Gupta, Sajal; Sikka, Suresh

2006-06-01

This review summarizes the role of free radicals and oxidative stress in the pathophysiology of human reproduction. An extensive review of the literature on the role of oxidative stress in influencing assisted reproduction and its outcome is described in this article. Free radicals or reactive oxygen species mediate their action through many of the proinflammatory cytokines and this mechanism has been proposed as a common underlying factor for endometriosis, ovarian cancer, polycystic ovary disease, and various other pathologies affecting the female reproductive process, as highlighted in this review. Oxidative stress, sperm DNA damage, and apoptosis have been implicated in male infertility. Elevated reactive oxygen species levels correlate with the poor fertility outcomes seen in the assisted reproductive technology setting. Oxidative stress has been implicated in male and female infertility, including fetal dysmorphogenesis, abortions, and intrauterine growth restriction. Accurate evaluation of seminal oxidative stress by standardized assays may help in the diagnosis and management of male infertility. There is evidence in the literature on the beneficial effects of oral antioxidant supplementation in male infertility. Current ongoing trials will provide answers on the safety and effectiveness of antioxidants in improving maternal and fetal outcomes. Further studies need to be conducted to determine if antioxidant supplementation will prevent fetal developmental defects in high-risk pregnancy with diabetes.

Evaluation of Antioxidant and Free Radical Scavenging Abilities of ...

African Journals Online (AJOL)

Objective: This study was aimed at determining the antioxidants and free radical scavenging abilities of some packaged fruit juices (PFJ) widely used as source of fluids in Nigeria. Materials and methods: Packaged fruit juice samples produced by The Coca cola Company and Chi company namely: Apple(AP), blackcurrant, ...

Total polyphenolic contents and in vitro antioxidant properties of eight Sida species from Western Ghats, India

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M D Subramanya

2015-01-01

Full Text Available 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, 2Ͳ-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.

Evaluation of Antioxidant Activity of Total Extract of Onopordon leptolepis L. in Vitro

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Einollah Valizadeh

2015-08-01

Full Text Available Background and objectives : Medicinal plants are valuable natural resources that have been considered nowadays in developed countries as raw materials for converting into safe drugs for human. Antioxidants are compounds that effectively prevent oxygen free radical reactions and reduce damage or cell death, cardiovascular diseases and cancer. Material and Methods : After extraction of floral and vegetative parts of Onopordon leptolepis plant, antioxidant potential was determined by two testes: 1. 1diphenyl-2-picrylhydrazyl (DPPH free radical-scavenging and ferric-reducing antioxidant power (FRAP. Results : The hydro-alcohol extract (methanol 70% of floral and vegetative parts of O. leptolepis plant was found as the most active in scavenging DPPH radicals and in FRAP. The antioxidant potential of hydro-alcohol (H.A70% extracts of the floral part of O.leptolepis showed weak effect than the extract of vegetative of O.leptolepis plant. Conclusion : Results showed that the hydro-alcohol extract (methanol 70% of vegetative part can be considered for medicinal and food industries due to the high antioxidant properties.

Measurement of total phenolic content and antioxidant activity of aerial parts of medicinal plant Coronopus didymus.

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Noreen, Hafiza; Semmar, Nabil; Farman, Muhammad; McCullagh, James S O

2017-08-01

To evaluate the total phenolic content and compare the antioxidant activity of various solvent extracts and fractions from the aerial parts of Coronopus didymus through various assays. Total phenolic content was determined using the Folin-Ciocalteu assay and the in vitro antioxidant activity of a number of different extracts was investigated in a dose-dependent manner with three different methods: the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and ferric reducing antioxidant power (FRAP) assays. A flavone was isolated from the most active ethanolic extract with high antioxidant activity using size exclusion chromatography. IC 50 values were calculated for the DPPH and ABTS methods. The FRAP activity was assessed in terms of μM Fe (II) equivalent. The phenolic content was found to be highest in the ethanol extract (CDA Et; 47.8 mM GAE) and the lowest in the dichloromethane extract (CDA DCM; 3.13 mM GAE). The ethanol extract showed high radical scavenging activity towards DPPH and ABTS radicals with IC 50 values of (7.80 × 10 2 ) and (4.32 × 10 2 ) μg/mL, respectively. The most active ethanol extract had a FRAP value of 1921.7 μM Fe (II) equivalent. The isolated flavone F10C (5,7,4'-trihydroxy-3'-methoxy flavone) was far more effective for scavenging free radicals in the DPPH and ABTS assays with IC 50 of 43.8 and 0.08 μg/mL, than the standard trolox, with IC 50 values of 97.5 and 21.1 μg/mL, respectively. In addition, the flavone F10C and the standard ascorbic acid had FRAP values of 1621.7 and 16 038.0 μM Fe (II) equivalents, respectively. The total phenolic content of extracts in decreasing order is ethanol extract (CDA Et) > acetone extract (CDA ACE) > phenolic extract (CDA MW) > n-hexane extract (CDA nHX)> chloroform extract (CDA CHL) > dichloromethane extract (CDA DCM). The ordering of extracts in terms of antioxidant activity from highest to lowest is CDA Et

Effects of EGTA and antioxidants on the interaction of phenothiazine free radicals with calmodulin

International Nuclear Information System (INIS)

Prozialeck, W.C.

1986-01-01

Upon irradiation with UV light or treatment with horseradish peroxidase (HRP), phenothiazines generate free radicals that bind irreversibly to calmodulin (CaM). The purpose of the present studies was to examine the effects of the Ca 2+ -chelator EGTA and various antioxidants on the binding of these phenothiazine radicals to CaM. Solutions containing 2 μM CaM, 10 μM 3 H-chlorpromazine, 10 μM CaCl 2 , and either EGTA or the antioxidants (2mM), were irradiated with UV light or treated with HRP-H 2 O 2 . Samples were dialyzed to remove free chlorpromazine and counted for radioactivity. The antioxidants (ascorbic acid, dithiothreitol and glutathione) inhibited the HRP-induced irreversible binding by 95-100% but had little effect on the UV-induced binding. EGTA inhibited the HRP-induced binding by 100% but reduced the UV-induced binding by only 70%. The inhibition of the UV-induced binding by EGTA could be prevented by incubating the samples in the presence of excess Ca 2+ . By contrast, Ca 2+ did not prevent the inhibition of the HRP-induced binding by EGTA. These findings indicate that EGTA and antioxidants inhibit the HRP-induced irreversible binding of chlorpromazine to CaM by interacting with the chlorpromazine free radical and not by modifying CaM or chelating Ca 2+ . The fact that the UV-induced binding is resistant to inhibition by the antioxidants suggests that chlorpromazine binds to the Ca 2+ -CaM complex before photoactivation causes the formation of the free radical

EPR investigation of zinc/iodine exchange between propargyl iodides and diethylzinc: detection of propargyl radical by spin trapping.

Science.gov (United States)

Maury, Julien; Jammi, Suribabu; Vibert, François; Marque, Sylvain R A; Siri, Didier; Feray, Laurence; Bertrand, Michèle

2012-10-19

The production of propargyl radicals in the reaction of dialkylzincs with propargyl iodides in nondegassed medium was investigated by EPR using tri-tert-butylnitrosobenzene (TTBNB) as a spin trap. The radical mechanism and the nature of the observed species were confirmed by the trapping of propargyl radicals generated by an alternative pathway: i.e., upon irradiation of propargyl iodides in the presence of hexa-n-butyldistannane. In dialkylzinc-mediated experiments a high concentration of adduct was instantaneously observed, whereas no spontaneous production of spin adduct was detected in a blank experiment performed with the propargylic iodide and TTBNB in the absence of diethylzinc. Under irradiation in the presence of distannane, two different species were observed at the very beginning of the irradiation; the nitroxide resulting from the trapping of propargyl radical at the propargyl carbon remained the only species detected after irradiating for several minutes. The absence of adducts resulting from the trapping of allenyl canonical forms was supported by DFT calculations and by the preparation of an authentic sample.

Iron-chelating agents never suppress Fenton reaction but participate in quenching spin-trapped radicals

International Nuclear Information System (INIS)

Li Linxiang; Abe, Yoshihiro; Kanagawa, Kiyotada; Shoji, Tomoko; Mashino, Tadahiko; Mochizuki, Masataka; Tanaka, Miho; Miyata, Naoki

2007-01-01

Hydroxyl radical formation by Fenton reaction in the presence of an iron-chelating agent such as EDTA was traced by two different assay methods; an electron spin resonance (ESR) spin-trapping method with 5,5-dimethyl-1-pyrroline N-oxide (DMPO), and high Performance liquid chromatography (HPLC)-fluorescence detection with terephthalic acid (TPA), a fluorescent probe for hydroxyl radicals. From the ESR spin-trapping measurement, it was observed that EDTA seemed to suppress hydroxyl radical formation with the increase of its concentration. On the other hand, hydroxyl radical formation by Fenton reaction was not affected by EDTA monitored by HPLC assay. Similar inconsistent effects of other iron-chelating agents such as nitrylotriacetic acid (NTA), diethylenetriamine penta acetic acid (DTPA), oxalate and citrate were also observed. On the addition of EDTA solution to the reaction mixture 10 min after the Fenton reaction started, when hydroxyl radical formation should have almost ceased but the ESR signal of DMPO-OH radicals could be detected, it was observed that the DMPO-OH· signal disappeared rapidly. With the simultaneous addition of Fe(II) solution and EDTA after the Fenton reaction ceased, the DMPO-OH· signal disappeared more rapidly. The results indicated that these chelating agents should enhance the quenching of [DMPO-OH]· radicals by Fe(II), but they did not suppress Fenton reaction by forming chelates with iron ions

Development of a new free radical absorption capacity assay method for antioxidants: aroxyl radical absorption capacity (ARAC).

Science.gov (United States)

Nagaoka, Shin-ichi; Nagai, Kanae; Fujii, Yuko; Ouchi, Aya; Mukai, Kazuo

2013-10-23

A new free radical absorption capacity assay method is proposed with use of an aroxyl radical (2,6-di-tert-butyl-4-(4'-methoxyphenyl)phenoxyl radical) and stopped-flow spectroscopy and is named the aroxyl radical absorption capacity (ARAC) assay method. The free radical absorption capacity (ARAC value) of each tocopherol was determined through measurement of the radical-scavenging rate constant in ethanol. The ARAC value could also be evaluated through measurement of the half-life of the aroxyl radical during the scavenging reaction. For the estimation of the free radical absorption capacity, the aroxyl radical was more suitable than the DPPH radical, galvinoxyl, and p-nitrophenyl nitronyl nitroxide. The ARAC value in tocopherols showed the same tendency as the free radical absorption capacities reported previously, and the tendency was independent of an oxygen radical participating in the scavenging reaction and of a medium surrounding the tocopherol and oxygen radical. The ARAC value can be directly connected to the free radical-scavenging rate constant, and the ARAC method has the advantage of treating a stable and isolable radical (aroxyl radical) in a user-friendly organic solvent (ethanol). The ARAC method was also successfully applied to a palm oil extract. Accordingly, the ARAC method would be useful in free radical absorption capacity assay of antioxidative reagents and foods.

ANTIOXIDANT ACTIVITY, TOTAL PHENOLIC AND FLAVONOID CONTENT OF MORINDA CITRIFOLIA FRUIT EXTRACTS FROM VARIOUS EXTRACTION PROCESSES

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PRAVEEN K. RAMAMOORTHY

2007-04-01

Full Text Available Soxhlet, Ultrasonic extract of Morinda citrifolia L. fruit and four extracts from high pressure extraction at 10 MPa using ethanol, ethyl acetate as solvent and dried by vacuum oven and spray dryer were analyzed for their antioxidant activity by peroxide value method and diphenylpicrylhydrazyl radical scavenging method. The five extracts along with the reference samples, butylated hydroxyl toluene and tannic acid were further analyzed to determine their total phenolic content by Folin-Ciocalteau method and total flavonoid content by Dowd method. The M. citrifolia extract by high pressure extraction with ethyl acetate as solvent and spray dried was found to exhibit highest antioxidant activity and total flavonoid content. High total phenolic content was determined in the high pressure extract using ethyl acetate as solvent and vacuum dried. It was interesting to note that ultrasonic extract exhibited significant antioxidant activity, total phenolic and flavonoid content. High pressure extracted M. citrifolia in ethanol was found to express lesser values comparatively. The significant difference in activity among the high pressure extracts was found to be due to the polarity of the solvents used for extraction as M. citrifolia fruit contains relatively larger quantity of non-polar antioxidant compounds. It was also found that the drying methods had significant impact on the antioxidant activity, total phenolic and flavonoid content of the extracts.

Antioxidant and DPPH (1,1-diphenyl-2-picrylhydrazyl Free Radical Scavenging Activities of Boniger Acid and Calix[4]arene Derivative

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E. ERDEM

2014-07-01

Full Text Available Diazonium derivative of calix[4]arene has been synthesized using three different synthetic steps. Initially p-tert-butylcalix[4]arene was synthesized with the condensation reaction of p-tert-butylphenol and formaldehyde in basic conditions. Calix[4]arene was obtained after the debutylation reaction of p-tert-butylcalix[4]arene with AlCl3. Calix[4]arene reacted with diazonium salt of Böniger acid to yield the 5,17-[(Bis(azo-bis(5-hydroxy-2,7-naphthalenedisulfonicacid]-25,26,27,28-tetrahydroxy calix[4]arene which has eight free phenolic hydroxyl group. Reaction steps were shown in Fig.1.2,7-naphthalenedisulfonicacid]-25,26,27,28-tetrahydroxy calix[4]arene The antioxidant activity of the Böniger acid and calix[4]aren derivative were determined using β-karotene-linoleic acid system. Moreover, the free radical scavenging activity values were tested with DPPH free radical. The two compounds showed strong antioxidant activity. Total antioxidant activity of Böniger acid and calix[4]aren derivative was determined using β–carotenelinoleic acid model system and was found the antioxidant activity of 84.00% and 85.60 % respectively. The free radical scavenging activities were determined as 83.05% and 84.69 %. Results show that, two compounds has the antioxidant activity. The calix[4]aren derivaties has more higher activity then Boniger acid because of calix[4]aren derivative has much hydroxl groups.

Effect of gibberellic acid on total antioxidant activity during Chenopodium rubrum L. ontogenesis invitro

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Mitrović Aleksandra

2009-01-01

Full Text Available Total antioxidant activity (TAA represents the combined ability of diverse antioxidants present in a sample of plant material to scavenge free radicals. Chenopodium rubrum L. sel. 184 is a qualitatively short-day plant; as an early-flowering species, it is a suitable object for studying ontogenesis in vitro. We investigated the effect of GA3 (5 mg/l on TAA during C. rubrum ontogenesis under two different inductive photoperiodic regimes in vitro. Total antioxidant activ­ity does not change in different phases of C. rubrum ontogenesis under the same photoperiodic treatment. Exposure to continuous irradiation caused an increase of TAA in both C. rubrum plants and collected matured seeds. Gibberellic acid stimulated stem elongation, but did not affect leaf development or the number of matured seeds per plant, regardless of photoperiodic treatment; it induced a decrease of TAA in C. rubrum plants regardless of photoperiodic treatment or the phase of development, while it had no effect on TAA of matured seeds.

Flavonoids, total phenolics and antioxidant capacity: comparison between commercial green tea preparations

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Débora Harumi Kodama

2010-12-01

Full Text Available The potential health benefits attributed to green tea and its catechins such as antioxidant effects, cancer chemoprevention, and weight loss have led to a huge increase of green tea products in the food market. The objectives of this work were to analyze and compare these products in terms of phenolic contents and in vitro antioxidant capacity including tea bags, dehydrated leaves, and ready-to-drink preparations after standardization of the infusion preparation procedure. Total phenolics content in 1 cup of the different teas varied from 90 to 341 mg of catechin equivalents, and the highest and the lowest values were both those of the ready-to-drink products. Infusions prepared from tea bags had contents varying from 96 to 201 mg.200 mL-1, and there were no significant differences among batches. The DPPH radical scavenging and the Oxygen Radical Absorbing Capacities (ORAC varied largely among the different tea preparations, from 23 to 131 mmoles of Trolox Equivalents (TE.200 mL-1 (DPPH, and from 1.2 to 5.1 mmoles of TE.200 mL-1 (ORAC, but again there were no differences among infusions or ready-to-drink commercial preparations. However, the antioxidant capacity of ready-to-drink products was partially due to the presence of other non-phenolic compounds such as ascorbic acid

Theoretical insights on the antioxidant activity of edaravone free radical scavengers derivatives

Science.gov (United States)

Cerón-Carrasco, José P.; Roy, Hélène M.; Cerezo, Javier; Jacquemin, Denis; Laurent, Adèle D.

2014-04-01

The prediction of antioxidant properties is not straightforward due to the complexity of the in vivo systems. Here, we use theoretical descriptors, including the potential of ionization, the electrodonating power and the spin density distribution, to characterize the antioxidant capacity of edaravone (EDV) derivatives. Our computations reveal the relationship between these parameters and their potential bioactivity as free radical scavengers. We conclude that more efficient antioxidants could be synthesized by tuning the R1 and R2 positions of the EDV structure, rather than modifying the R3 group. Such modifications might improve the antioxidant activity in neutral and deprotonated forms.

Functional Teas from the Leaves of Arbutus unedo: Phenolic Content, Antioxidant Activity, and Detection of Efficient Radical Scavengers.

Science.gov (United States)

Erkekoglou, Ioannis; Nenadis, Nikolaos; Samara, Efrosini; Mantzouridou, Fani Th

2017-06-01

The phenolic content/composition and antioxidant activity of hot/cold infusion and decoction from the leaves of Arbutus unedo were studied for the first time. 1,1-diphenyl-2-picrylhydrazyl (DPPH ● ), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS ●+ ), crocin-bleaching, copper-reducing, and liposome accelerated oxidation assays were used for the evaluation of the activity in vitro. In vivo, the extracts were examined for their ability to protect S. cerevisiae cells from H 2 O 2 induced oxidative stress. An on-line high-performance liquid chromatography-DPPH ● assay was applied to identify potent radical scavengers and comment on their contribution to the total activity. The addition of leaves to boiling water (decoction) was the most appropriate practice to apply since the highest phenol intake (220.2 mg gallic acid/cup served) was obtained. Additionally, its antioxidant activity was equal or superior to that of the other extracts. Flavonols (~51-61 mg/g dry extract) were the main phenols in all the extracts, with quercitrin accounting for ~20% of the total phenol amount. The on-line DPPH ● method verified the high potency of the decoction and indicated as the most active radical scavengers, two galloylquinic acid derivatives and myricitrin, accounting for ~28-45% and ~11-13% of the total scavenging, respectively. Present data may contribute to the future exploitation of A. unedo leaves by the food industry for health-promoting herbal tea preparations and dietary supplements.

Streptomyces sp. MUM212 as a Source of Antioxidants with Radical Scavenging and Metal Chelating Properties

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Loh Teng-Hern Tan

2017-05-01

Full Text Available Reactive oxygen species and other radicals potentially cause oxidative damage to proteins, lipids, and DNA which may ultimately lead to various complications including mutations, carcinogenesis, neurodegeneration, cardiovascular disease, aging, and inflammatory disease. Recent reports demonstrate that Streptomyces bacteria produce metabolites with potent antioxidant activity that may be developed into therapeutic drugs to combat oxidative stress. This study shows that Streptomyces sp. MUM212 which was isolated from mangrove soil in Kuala Selangor, Malaysia, could be a potential source of antioxidants. Strain MUM212 was characterized and determined as belonging to the genus Streptomyces using 16S rRNA gene phylogenetic analysis. The MUM212 extract demonstrated significant antioxidant activity through DPPH, ABTS and superoxide radical scavenging assays and also metal-chelating activity of 22.03 ± 3.01%, 61.52 ± 3.13%, 37.47 ± 1.79%, and 41.98 ± 0.73% at 4 mg/mL, respectively. Moreover, MUM212 extract was demonstrated to inhibit lipid peroxidation up to 16.72 ± 2.64% at 4 mg/mL and restore survival of Vero cells from H2O2-induced oxidative damages. The antioxidant activities from the MUM212 extract correlated well with its total phenolic contents; and this in turn was in keeping with the gas chromatography–mass spectrometry analysis which revealed the presence of phenolic compounds that could be responsible for the antioxidant properties of the extract. Other chemical constituents detected included hydrocarbons, alcohols and cyclic dipeptides which may have contributed to the overall antioxidant capacity of MUM212 extract. As a whole, strain MUM212 seems to have potential as a promising source of novel molecules for future development of antioxidative therapeutic agents against oxidative stress-related diseases.

IN VIVO EVIDENCE OF FREE RADICAL FORMATION AFTER ASBESTOS INSTILLATION: AN ESR SPIN TRAPPING INVESTIGATION

Science.gov (United States)

It has been postulated that the in vivo toxicity of asbestos results from its catalysis of free radical generation. We examined in vivo radical production using electron spin resonance (ESR) coupled with the spin trap alpha-(4-pyridyl-1-oxide)-N-t-butylnitrone (4-POBN); 180 d...

Modification of dispersibility of nanodiamond by grafting of polyoxyethylene and by the introduction of ionic groups onto the surface via radical trapping

International Nuclear Information System (INIS)

Cha, I.; Hashimoto, K.; Fujiki, K.; Yamauchi, T.; Tsubokawa, N.

2014-01-01

To improve the dispersibility of polycrystalline nanodiamond (ND) in solvents, the grafting of polymers and introduction of ionic groups onto ND surface via radical trapping by ND surface were investigated. The grafting of polyoxyethylene (POE) onto ND surface by trapping of POE radicals formed by the thermal decomposition of POE macro azo-initiator (Azo-POE) was examined. The polymer radicals formed by the thermal decomposition of Azo-POE were successfully trapped by ND surface to give POE-grafted ND. The effect of temperature on the grafting of POE onto ND was discussed. In addition, the introduction of cationic protonated amidine groups onto ND was achieved by the trapping of radicals bearing protonated amidine groups formed by thermal decomposition of 2,2′-azobis(2-methylpropionamidine)dihydrochloride (AMPA). The anionic carboxylate groups was introduced onto ND surface by the trapping of the radicals bearing carboxyl groups formed by thermal decomposition of 4,4′-azobis(4-cyonovaleric acid) (ACVA) followed by the treatment with NaOH aqueous solution. The dispersibility of ND in water was remarkably improved by the grafting of POE, based on the steric hindrance of polymer chains and by the introduction of ionic groups, based on the ionic repulsion, onto ND surface. - Highlights: • Grafting of PEG onto nanodiamond was achieved by radical trapping. • Introduction of ionic groups onto nanodiamond was achieved by radical trapping. • Nanodiamond was dispersed by PEG grafting based on steric hindrance of PEG chains. • Nanodiamond was dispersed by introduction of ionic groups based on ionic repulsion

Modification of dispersibility of nanodiamond by grafting of polyoxyethylene and by the introduction of ionic groups onto the surface via radical trapping

Energy Technology Data Exchange (ETDEWEB)

Cha, I. [Graduate School of Science and Technology, Niigata University, 8050, Ikarashi, 2-no-cho, Nishi-ku, Niigata 950-2181 (Japan); Hashimoto, K. [Department of Material Science and Technology, Faculty of Engineering, Niigata University, 8050, Ikarashi, 2-no-cho, Nishi-ku, Niigata 950-218 (Japan); Fujiki, K. [Department of Environmental Science, Niigata Institute of Technology, 1719, Fujihashi, Kashiwazaki, Niigata 945-1195 (Japan); Yamauchi, T. [Graduate School of Science and Technology, Niigata University, 8050, Ikarashi, 2-no-cho, Nishi-ku, Niigata 950-2181 (Japan); Department of Material Science and Technology, Faculty of Engineering, Niigata University, 8050, Ikarashi, 2-no-cho, Nishi-ku, Niigata 950-218 (Japan); Tsubokawa, N., E-mail: ntsuboka@eng.niigata-u.ac.jp [Graduate School of Science and Technology, Niigata University, 8050, Ikarashi, 2-no-cho, Nishi-ku, Niigata 950-2181 (Japan); Department of Material Science and Technology, Faculty of Engineering, Niigata University, 8050, Ikarashi, 2-no-cho, Nishi-ku, Niigata 950-218 (Japan)

2014-02-14

To improve the dispersibility of polycrystalline nanodiamond (ND) in solvents, the grafting of polymers and introduction of ionic groups onto ND surface via radical trapping by ND surface were investigated. The grafting of polyoxyethylene (POE) onto ND surface by trapping of POE radicals formed by the thermal decomposition of POE macro azo-initiator (Azo-POE) was examined. The polymer radicals formed by the thermal decomposition of Azo-POE were successfully trapped by ND surface to give POE-grafted ND. The effect of temperature on the grafting of POE onto ND was discussed. In addition, the introduction of cationic protonated amidine groups onto ND was achieved by the trapping of radicals bearing protonated amidine groups formed by thermal decomposition of 2,2′-azobis(2-methylpropionamidine)dihydrochloride (AMPA). The anionic carboxylate groups was introduced onto ND surface by the trapping of the radicals bearing carboxyl groups formed by thermal decomposition of 4,4′-azobis(4-cyonovaleric acid) (ACVA) followed by the treatment with NaOH aqueous solution. The dispersibility of ND in water was remarkably improved by the grafting of POE, based on the steric hindrance of polymer chains and by the introduction of ionic groups, based on the ionic repulsion, onto ND surface. - Highlights: • Grafting of PEG onto nanodiamond was achieved by radical trapping. • Introduction of ionic groups onto nanodiamond was achieved by radical trapping. • Nanodiamond was dispersed by PEG grafting based on steric hindrance of PEG chains. • Nanodiamond was dispersed by introduction of ionic groups based on ionic repulsion.

A comparison of the antioxidant activity with the Total Phenolic and ...

African Journals Online (AJOL)

Thus, radical scavenging as well as antioxidant potentials of the plant are good indications of its effectiveness in disease management. Objective: This study evaluates the antioxidant activity of the extracts from the leaves and stem bark of Anogeissus leiocarpa.. Materials and Methods: Dried powdered leaves and bark were ...

Oxidative stress and total antioxidant status in term newborns and their mothers

Directory of Open Access Journals (Sweden)

Maria Wilinska

2015-12-01

Full Text Available The peripartum period and delivery are considered critical for maintaining a balance between the production of free oxygen radicals and functional incompetence of the antioxidant system of a foetus and a neonate. [b]Objective.[/b] The aim of the study was to evaluate the oxidoreductive state of mothers and their newborns immediately after delivery and in the first few days after birth. [b]Method.[/b] Eighty-five mothers and their healthy, term newborns were included into the prospective study. Total antioxidant capacity (TAC and thiobarbituric acid reactive substances (TBARS in maternal placenta and milk, as well as blood and urine of the neonates on the first and third day after birth, were examined. [b]Results.[/b] Elevated levels of TBARS were found in maternal placenta and neonatal blood on the third day after birth, but low concentrations were observed in maternal milk. On the contrary, total antioxidant status (TAS showed a declining tendency in neonatal blood and an increasing tendency in breast milk. Markers of oxidative stress and antioxidant capacity were independent of the mode of delivery. [b]Conclusions.[/b] Values of oxidative stress markers in mothers and newborns immediately after birth were elevated and increased further during the first few days of neonatal life. Breast milk was the only nutritional substance with high antioxidant activity. At the same time, TBARS levels in breast milk decreased, which might indicate its protective role in reducing oxidative stress in newborns.

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

Science.gov (United States)

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.

Electron spin resonance of spin-trapped radicals of amines and polyamines. Hydroxyl radical reactions in aqueous solutions and. gamma. radiolysis in the solid state

Energy Technology Data Exchange (ETDEWEB)

Mossoba, M.M.; Rosenthal, I.; Riesz, P. (National Cancer Inst., Bethesda, MD (USA))

1982-06-15

The reactions of hydroxyl radicals with methylamine, dimethylamine, trimethylamine, diethylamine, sec-butylamine, ethylene-diamine, 1,3-diaminopropane, putrescine, cadaverine, 1,7-diaminoheptane, ornithine, spermidine, spermine, agmatine, and arcaine in aqueous solutions have been investigated by spin-trapping and esr. Hydroxyl radicals were generated by the uv photolysis of H/sub 2/O/sub 2/ and 2-methyl-2-nitrosopropane (MNP) was used as the spin-trap. The effects of ionizing radiation on the same polyamines in the polycrystalline state were also investigated. The free radicals produced by ..gamma..-radiolysis of these solids at room temperature in the absence of air were identified by dissolution in aqueous solutions of MNP. The predominant reaction of OH radicals with amines and polyamines below pH 7 was the abstraction of hydrogen atoms from a carbon that is not adjacent to the protonated amino group. For agmatine and arcaine which contain guanidinium groups abstraction occurred from the ..cap alpha..-CH. Dimethylamine was oxidized to the dimethylnitroxyl radical by H/sub 2/O/sub 2/ in the dark. ..gamma..-Radiolysis of polyamines in the polycrystalline state generated radicals due to H-abstraction from either the ..cap alpha..-Ch or from a carbon atom in the middle of the alkyl chain. The deamination radical was obtained from ornithine.

Effect of gamma irradiation on antioxidant properties of ber (Zizyphus mauritiana) fruit

International Nuclear Information System (INIS)

Kavitha, C.; Kuna, Aparna; Sagar, S.B.; Padmavati, T.V.N.; Supraja, T.; Prabhakar, N.

2015-01-01

Effect of gamma irradiation (0.25 to 1.0kGy) on antioxidant properties of ber fruit was studied. Antioxidant properties of ber fruits were determined by scavenging DPPH radical activity, reducing power assay, super oxide anion radical activity, TBARS, total phenolic content and total flavonoid content. Gamma irradiation treatment up to 1.0 kGy elevated the scavenging DPPH radical activity (9 %), super oxide anion radical activity (26 %) and total flavonoid content (208 %) compared to fresh ber fruit. On the other hand it brought down the reducing power activity (65 %) and total phenolic content (18 %) as compared to raw fruit. The TBARS activity statistically increased upon irradiation of ber fruit. It indicated that total antioxidant activity decreased as TBARS value increased. Therefore 0.25 to 0.5kGy is better dose to retain the natural antioxidant in fruit. (author)

Reduced serum non-enzymatic antioxidant defense and increased lipid peroxidation in schizophrenic patients on a hypocaloric diet.

Science.gov (United States)

Zortea, Karine; Fernandes, Brisa Simões; Guimarães, Lísia Rejane; Francesconi, Lenise Petter; Lersch, Camila; Gama, Clarissa Severino; Schroeder, Rafael; Zanotto-Filho, Alfeu; Moreira, José Claudio; Lobato, Maria Inês Rodrigues; Belmonte-de-Abreu, Paulo Silva

2012-03-14

Growing evidence suggests that oxidative stress (OS) may be associated with the pathophysiology underlying schizophrenia (SZ). Some studies indicate that nutritional supplements offer protection from OS, but there is no data about the effect of a hypocaloric diet on OS in this population. Therefore, we aimed to study the effect of a hypocaloric dietary intervention on OS in subjects with SZ. A cross-sectional study of 96 participants in outpatient treatment for SZ comprised patients separated into two groups: one group of subjects followed a hypocaloric diet (HD) program (n=42), while the other group followed a regular diet (RD) with no nutritional restrictions (n=54). The serum total radical-trapping antioxidant parameter (TRAP), total antioxidant reactivity (TAR) and thiobarbituric acid reactive species (TBARS) levels were assessed. TRAP levels were lower and TBARS levels were higher in the HD group than in the RD group (p=0.022 and p=0.023, respectively). There were no differences in TAR levels between the groups. Additionally, there was a positive correlation between TRAP and TBARS levels after adjusting for BMI and clozapine dose (partial correlation=0.42, pdiet and the levels of TRAP, TBARS, and TAR. Subjects with SZ on a hypocaloric diet displayed different OS parameters than those not following a HD. Serum TRAP levels were lower and TBARS levels were higher among SZ subjects with HD compared to SZ subjects without HD. Lower TRAP levels may reflect decreased oxidative stress, whereas higher TBARS levels most likely reflect a biochemical reaction to the decreased TRAP levels. Additionally, TAR levels were similar between groups, suggesting a similar quality of antioxidant defenses, despite quantitative differences between the two dietary protocols in SZ patients under outpatient care. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Effects of Puerariae Radix extract on the activity of antioxidant

OpenAIRE

Young-Joon Eun; Ki Rok Kwon; Tae Jin Rhim; Yun-Kyung Song; Hyung-Ho Lim

2007-01-01

Objective : The objective of this study was to investigate the antioxidative effects of Puerariae Radix extract. Method : Total antioxidant capacity (TAC), Total antioxidant response (TAR), Total phenolic content, Reactive oxygen species (ROS), 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activities, lipid peroxidation were examined. Result : Total antioxidant status was examined by total antioxidant capacity(TAC) and total antioxidant response(TAR) against potent free r...

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

Science.gov (United States)

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.

Study of anti-oxidation and scavenging effects on free radicals of quercetin

International Nuclear Information System (INIS)

Wang Chongdao; Qiang Yizhong; Lao Qinhua; Shao Yuan

1999-01-01

The effects of Quercetin on the contents of lipid peroxides (LPO) in the mice caused by γ-whole-body irradiation by method of the modified spectrophotometry of TBA, and the scavenging effects of Quercetin on the free radicals of DNA induced by radiation exposure by means of ESR technique were investigated. The results demonstrates that Quercetin has a good anti-oxidation effect and is very effective in scavenging of free radicals

Total Phenolics and Antioxidant Capacity of Some Nigerian ...

African Journals Online (AJOL)

The results suggest that the beverages possess significant radical scavenging ability that may be ... prepared and 1 ml of it was mixed with 1 ml, 0.4 ... 734nm to 0.700 with ethanol. .... cocoa fermentation, polyphenols are subjected to .... Variability in antioxidant activity in ... tea, coffee and wine. .... The kinetics of polyphenol.

Chronic ozone exposure alters the secondary metabolite profile, antioxidant potential, anti-inflammatory property, and quality of red pepper fruit from Capsicum baccatum.

Science.gov (United States)

Bortolin, Rafael Calixto; Caregnato, Fernanda Freitas; Divan Junior, Armando Molina; Zanotto-Filho, Alfeu; Moresco, Karla Suzana; Rios, Alessandro de Oliveira; Salvi, Aguisson de Oliveira; Ortmann, Caroline Flach; de Carvalho, Pâmela; Reginatto, Flávio Henrique; Gelain, Daniel Pens; Moreira, José Cláudio Fonseca

2016-07-01

Tropospheric ozone (O3) background concentrations have increased since pre-industrial times, reaching phytotoxic concentrations in many regions globally. However, the effect of high O3 concentrations on quality of fruit and vegetables remains unknown. Here, we evaluated whether O3 pollution alters the quality of Capsicum baccatum peppers by changing the secondary compound profiles and biological activity of the fruit. C. baccatum pepper plants were exposed to ozone for 62 days in an open-top chamber at a mean O3 concentration of 171.6µg/m(3). Capsaicin levels decreased by 50% in the pericarp, but remained unchanged in the seeds. In contrast, the total carotenoid content increased by 52.8% in the pericarp. The content of total phenolic compounds increased by 17% in the pericarp. The total antioxidant potential decreased by 87% in seeds of O3-treated plants. The seeds contributed more than the pericarp to the total radical-trapping antioxidant potential and total antioxidant reactivity. O3 treatment impaired the ferric-reducing antioxidant power of the seeds and reduced NO(•)-scavenging activity in the pericarp. However, O3 treatment increased ferrous ion-chelating activity and hydroxyl radical-scavenging activity in the pericarp. Our results confirm that O3 alters the secondary metabolite profile of C. baccatum pepper fruits and, consequently, their biological activity profile. Copyright © 2016 Elsevier Inc. All rights reserved.

Polysulfides and products of H2S/S-nitrosoglutathione in comparison to H2S, glutathione and antioxidant Trolox are potent scavengers of superoxide anion radical and produce hydroxyl radical by decomposition of H2O2.

Science.gov (United States)

Misak, Anton; Grman, Marian; Bacova, Zuzana; Rezuchova, Ingeborg; Hudecova, Sona; Ondriasova, Elena; Krizanova, Olga; Brezova, Vlasta; Chovanec, Miroslav; Ondrias, Karol

2018-06-01

Exogenous and endogenously produced sulfide derivatives, such as H 2 S/HS - /S 2- , polysulfides and products of the H 2 S/S-nitrosoglutathione interaction (S/GSNO), affect numerous biological processes in which superoxide anion (O 2 - ) and hydroxyl (OH) radicals play an important role. Their cytoprotective-antioxidant and contrasting pro-oxidant-toxic effects have been reported. Therefore, the aim of our work was to contribute to resolving this apparent inconsistency by studying sulfide derivatives/free radical interactions and their consequent biological effects compared to the antioxidants glutathione (GSH) and Trolox. Using the electron paramagnetic resonance (EPR) spin trapping technique and O 2 - , we found that a polysulfide (Na 2 S 4 ) and S/GSNO were potent scavengers of O 2 - and cPTIO radicals compared to H 2 S (Na 2 S), GSH and Trolox, and S/GSNO scavenged the DEPMPO-OH radical. As detected by the EPR spectra of DEPMPO-OH, the formation of OH in physiological solution by S/GSNO was suggested. All the studied sulfide derivatives, but not Trolox or GSH, had a bell-shaped potency to decompose H 2 O 2 and produced OH in the following order: S/GSNO > Na 2 S 4  ≥ Na 2 S > GSH = Trolox = 0, but they scavenged OH at higher concentrations. In studies of the biological consequences of these sulfide derivatives/H 2 O 2 properties, we found the following: (i) S/GSNO alone and all sulfide derivatives in the presence of H 2 O 2 cleaved plasmid DNA; (ii) S/GSNO interfered with viral replication and consequently decreased the infectivity of viruses; (iii) the sulfide derivatives induced apoptosis in A2780 cells but inhibited apoptosis induced by H 2 O 2 ; and (iv) Na 2 S 4 modulated intracellular calcium in A87MG cells, which depended on the order of Na 2 S 4 /H 2 O 2 application. We suggest that the apparent inconsistency of the cytoprotective-antioxidant and contrasting pro-oxidant-toxic biological effects of sulfide derivatives results from their time

Total free radical species and oxidation equivalent in polluted air.

Science.gov (United States)

Wang, Guoying; Jia, Shiming; Niu, Xiuli; Tian, Haoqi; Liu, Yanrong; Chen, Xuefu; Li, Lan; Zhang, Yuanhang; Shi, Gaofeng

2017-12-31

Free radicals are the most important chemical intermediate or agent of the atmosphere and influenced by thousands of reactants. The free radicals determine the oxidizing power of the polluted air. Various gases present in smog or haze are oxidants and induce organ and cellular damage via generation of free radical species. At present, however, the high variability of total free radicals in polluted air has prevented the detection of possible trends or distributions in the concentration of those species. The total free radicals are a kind of contaminants with colorless, tasteless characteristics, and almost imperceptible by human body. Here we present total free radical detection and distribution characteristics, and analyze the effects of total free radicals in polluted air on human health. We find that the total free radical values can be described by not only a linear dependence on ozone at higher temperature period, but also a linear delay dependence on particulate matter at lower temperature period throughout the measurement period. The total free radical species distribution is decrease from west to east in Lanzhou, which closely related to the distribution of the air pollutants. The total free radical oxidation capacity in polluted air roughly matches the effects of tobacco smoke produced by the incomplete combustion of a controlled amount of tobacco in a smoke chamber. A relatively unsophisticated chromatographic fingerprint similarity is used for indicating preliminarily the effect of total free radicals in polluted air on human health. Copyright © 2017 Elsevier B.V. All rights reserved.

Antiproliferative activity in tumor cell lines, antioxidant capacity and total phenolic, flavonoid and tannin contents of Myrciaria floribunda

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LUIS A.C. TIETBOHL

Full Text Available ABSTRACT Myrciaria floribunda (H. West ex Willd. O. Berg, Myrtaceae, is a native plant species of the Atlantic Rain Forest, from north to south of Brazil. The lyophilized ethyl acetate extract from the leaves of M. floribunda was investigated for its antiproliferative activity in tumor cell lines, antioxidant capacity and its total phenolic, flavonoid and tannin contents. Antiproliferative activity was tested in vitro against seven human cancer cells and against immortalized human skin keratinocytes line (HaCat, no cancer cell. Antioxidant activity was determined using 1-diphenyl-2-picrylhydrazyl (DPPH radical scavenging and oxygen radical absorbing capacity (ORAC assays and total phenolic, flavonoid and tannin contents were determined by spectrophotometric techniques. Ethyl acetate extract of M. floribunda exhibited antiproliferative activity against cancer cell lines with total growth inhibition (TGI between 69.70 and 172.10 µg/mL. For HaCat cell, TGI value was 213.60 µg/mL. M. floribunda showed a strong antioxidant potential: EC50 of 45.89±0.42 µg/mL and 0.55±0.05 mmol TE/g for DPPH and ORAC, respectively. Total phenolic content was 0.23±0.013g gallic acid equivalents (GAE/g extract and exhibited 13.10±1.60% of tannins content. The content of flavonoid was 24.08±0.44% expressed as rutin equivalents. These results provide a direction for further researches about the antitumoral potential of M. floribunda.

Antioxidant, lipid peroxidation inhibition and free radical scavenging efficacy of a diterpenoid compound sugiol isolated from Metasequoia glyptostroboides.

Science.gov (United States)

Bajpai, Vivek K; Sharma, Ajay; Kang, Sun Chul; Baek, Kwang-Hyun

2014-01-01

To investigate the antioxidant efficacy of a biologically active diterpenoid compound sugiol isolated from Metasequoia glyptostroboides (M. glyptostroboides) in various antioxidant models. An abietane type diterpenoid sugiol, isolated from ethyl acetate extract of M. glyptostroboides cones, was analyzed for its antioxidant efficacy as reducing power ability and lipid peroxidation inhibition as well as its ability to scavenge free radicals such as 1,1-diphenyl-2-picryl hydrazyl, nitric oxide, superoxide and hydroxyl radicals. The sugiol showed significant and concentration-dependent antioxidant and free radical scavenging activities. Consequently, the sugiol exerted lipid peroxidation inhibitory effect by 76.5% as compared to α-tocopherol (80.13%) and butylated hydroxyanisole (76.59%). In addition, the sugiol had significant scavenging activities of 1,1-diphenyl-2-picryl hydrazyl, nitric oxide, superoxide and hydroxyl free radicals in a concentration-dependent manner by 78.83%, 72.42%, 72.99% and 85.04%, when compared to the standard compound ascorbic acid (81.69%, 74.62%, 73.00% and 73.79%) and α-tocopherol/butylated hydroxyanisole (84.09%, 78.61%, 74.45% and 70.02%), respectively. These findings justify the biological and traditional uses of M. glyptostroboides or its secondary metabolites as confirmed by its promising antioxidant efficacy. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Effect of growth stages on total phenolics content and antioxidant activity of Fumaria vaillantii L.

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L. Mehdizadeh*

2017-11-01

Full Text Available Background and objectives: Plant extracts and their constituents are known to exert biological effects, especially antioxidant activity. Fumaria vaillantii (Fumariaceae has several therapeutic effects in traditional medicine. Antioxidants are able to protect the human body from oxidative damage connected to the reaction of free radicals. Synthetic antioxidants have toxic and carcinogenic effects on human health; therefore, their application has been limited. Thus, there has been an increasing interest in the natural antioxidant compounds to prevent the foods from deterioration. In this study, the antioxidant activity of F. vaillantii extracts at three stages of growth has been evaluated. Methods: The ethanol extracts from the aerial parts of the plants at different phenological stages were prepared and the total phenolics content was determined by Folin-Ciocalteu reagent. Also, the antioxidant activity were determined by three methods as 2,2-diphenyl-1-picrylhydrazyl (DPPH, ferric-ion reducing antioxidant power (FRAP and phosphomolybdenum complex tests. All experiments were carried out in triplicate, and data were subjected to ANOVA according to the SAS software. Results: Total phenolics content of vegetative, budding and flowering stages were 68.38, 71.11 and 56.42 mg GAE/g extract, respectively. Although flowering stage showed the highest antioxidant activity in phosphomolybdenum complex, in DPPH and FRAP methods, it decreased from vegetative to flowering stages. Conclusion: According to the results, the Iranian F. vaillantii extract from vegetative stage was a potential source of natural antioxidants for food and pharmaceutical industries that can be used in different industries.

Total phenolic content and in-vitro antioxidant activities from methanolic extract of alligator pipefish, Syngnathoides biaculeatus (Bloch, 1785)

Digital Repository Service at National Institute of Oceanography (India)

Sanaye, S.V.; Pise, N.M.; Pawar, A.P.; Parab, P.P.; Sreepada, R.A.; Pawar, H.B.; Murugan, A.

-vitro antioxidant activities in terms of reducing power (RP), metal chelating activity (MCA), 2,2 diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), inhibition of lipid peroxidation (LPX) and hydroxyl radical...

Total phenolics, flavonoids, tannins and antioxidant activity of lima beans conserved in a Brazilian Genebank

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Tânia da Silveira Agostini-Costa

2015-02-01

Full Text Available The objective of this study was to characterize for the first time polyphenols and DPPH (2-diphenyl-1-picryhydrazyl radical antioxidant activity in commonly cultivated accessions of Phaseolus lunatus from an ex situ germplasm collection maintained by Embrapa, in Brazil. Furthermore, the study aimed to detect changes in total polyphenols, total flavonoids and condensed tannin for the same accessions after regeneration in a greenhouse. The results showed the diversity of the lima bean collection for phenolic compounds, which were strongly correlated with antioxidant activity. Lima beans accessions with the highest polyphenols and antioxidant activity were those with colored seeds. Conservation through cold storage of P. lunatus seeds in a cold chamber in the germplasm collection did not necessarily affect phenolic compounds. Variations observed in values after regeneration seeds may be mainly results of biotic and abiotic factors, including not only cultivar, but also environmental conditions. This study suggests that polyphenols in the lima beans present antioxidant activity, with possible beneficial effects for human health. It was expected that the potential of this tasty legume can be also used as a functional food crop and/or as a new ingredient in gastronomy.

TOTAL PHENOLIC CONTENT, ANTIOXIDANT AND ANTIBACTERIAL ACTIVITIES OF THE EXTRACT OF EPHEDRA PROCERA FISCH. ET MEY.

Science.gov (United States)

Dehkordi, Naser Vahed; Kachouie, Mehrdad Ataie; Pirbalouti, Abdollah Ghasemi; Malekpoor, Fatemeh; Rabei, Mohammad

2015-01-01

Ephedra prcera belonging to the family Ephedraceae is a poison and medicinal plant. The main aim of present study was to determine total phenolic content and antioxidant and antibacterial activities of ethanolic extract from the aerial parts of E. procera collected from a natural habitat in Chaharmahal va Bakhtiari province, Southwestern Iran. The total phenolic content of the extract by Folin-Ciocalteu method and the antioxidant activity using DPPH assay were determined. The antibacterial activity, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) of the extract were evaluated against five bacteria, including Proteus vulgaris, Pseudomonas aeruginosa, Enteobacter aeogenes, Bacillus ceirus and Staphylococcus aureus. Total phenolic content in the extract of E. procera was 0.718 mg tannic acid/g dry weight extract. The results indicated that the ethanolic extract of E. piocera exhibited radical scavenging activity. In addition, the results of this study confirmed that the ethanolic extract of E. procera exhibited antibacterial activity. In conclusion, the extract of E. piocera could be an important source of phenolic components with antioxidant capacity and antibacterial activity.

Effects of P25 TiO2 Nanoparticles on the Free Radical-Scavenging Ability of Antioxidants upon Their Exposure to Simulated Sunlight.

Science.gov (United States)

Li, Meng; Chong, Yu; Fu, Peter P; Xia, Qingsu; Croley, Timothy R; Lo, Y Martin; Yin, Jun-Jie

2017-11-15

Although nanosized ingredients, including TiO 2 nanoparticles (NPs), can be found in a wide range of consumer products, little is known about the effects these particles have on other active compounds in product matrices. These NPs can interact with reactive oxygen species (ROS), potentially disrupting or canceling the benefits expected from antioxidants. We used electron spin resonance spectrometry to assess changes in the antioxidant capacities of six dietary antioxidants (ascorbic acid, α-tocopherol, glutathione, cysteine, epicatechin, and epicatechin gallate) during exposure to P25 TiO 2 and/or simulated sunlight. Specifically, we determined the ability of these antioxidants to scavenge 1-diphenyl-2-picryl-hydrazyl radical, superoxide radical, and hydroxyl radical. Exposure to simulated sunlight alone did not lead to noticeable changes in radical-scavenging abilities; however, in combination with P25 TiO 2 NPs, the scavenging abilities of most antioxidants were weakened. We found glutathione to be the most resistant to treatment with sunlight and NPs among these six antioxidants.

Reaction between peroxynitrite and boronates: EPR spin-trapping, HPLC analyses, and quantum mechanical study of the free radical pathway

Science.gov (United States)

Sikora, Adam; Zielonka, Jacek; Lopez, Marcos; Dybala-Defratyka, Agnieszka; Joseph, Joy; Marcinek, Andrzej; Kalyanaraman, Balaraman

2013-01-01

Recently we showed that peroxynitrite (ONOO−) reacts directly and rapidly with aromatic and aliphatic boronic acids (k ≈ 106 M−1s−1). Product analyses and substrate consumption data indicated that ONOO− reacts stoichiometrically with boronates, yielding the corresponding phenols as the major product (~85–90%), and the remaining products (10–15%) were proposed to originate from free radical intermediates (phenyl and phenoxyl radicals). Here we investigated in detail the minor, free radical pathway of boronate reaction with ONOO−. The electron paramagnetic resonance (EPR) spin-trapping technique was used to characterize the free radical intermediates formed from the reaction between boronates and ONOO−. Using 2-methyl-2-nitrosopropane (MNP) and 5-diethoxyphosphoryl-5-methyl-1-pyrroline-N-oxide (DEPMPO) spin traps, phenyl radicals were trapped and detected. Although phenoxyl radicals were not detected, the positive effects of molecular oxygen, and inhibitory effects of hydrogen atom donors (acetonitrile, and 2-propanol) and general radical scavengers (GSH, NADH, ascorbic acid and tyrosine) on the formation of phenoxyl radical-derived nitrated product, suggest that phenoxyl radical was formed as the secondary species. We propose that the initial step of the reaction involves the addition of ONOO− to the boron atom in boronates. The anionic intermediate undergoes both heterolytic (major pathway) and homolytic (minor pathway) cleavage of the peroxy (O-O) bond to form phenol and nitrite as a major product (via a non-radical mechanism), or a radical pair PhB(OH)2O•−…•NO2 as a minor product. It is conceivable that phenyl radicals are formed by the fragmentation of PhB(OH)2O•− radical anion. According to the DFT quantum mechanical calculations, the energy barrier for the dissociation of PhB(OH)2O•− radical anion to form phenyl radicals is only a few kcal/mol, suggesting rapid and spontaneous fragmentation of PhB(OH)2O•− radical anion

Antioxidant Contents and Antioxidant Activities of White and Colored Potatoes (Solanum tuberosum L.).

Science.gov (United States)

Lee, Sang Hoon; Oh, Seung Hee; Hwang, In Guk; Kim, Hyun Young; Woo, Koan Sik; Woo, Shun Hee; Kim, Hong Sig; Lee, Junsoo; Jeong, Heon Sang

2016-06-01

This study was performed to evaluate and compare the antioxidant substance content and antioxidant activities of white (Superior) and colored (Hongyoung, Jayoung, Jasim, Seohong, and Jaseo) potatoes. The potatoes were extracted with 80% ethanol and were evaluated for the total polyphenol, flavonoid, and anthocyanin contents and for 1,1-diphenyl- 2-picrylhydrazyl (DPPH)/2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity, reducing power, and ferrous metal ion chelating effect. The total polyphenol, flavonoid, and anthocyanin contents of Hongyoung and Jayoung were higher than white and other colored potatoes. All colored potato extracts, except for Jaseo and Seohong, showed higher ABTS radical scavenging activities than the general white potato extract. Hongyoung and Jayoung had the highest ABTS and DPPH radical scavenging activities. Optical density values for the reducing power of Jayoung and Jaseo at concentration of 2 mg/mL were 0.148 and 0.090, respectively. All colored potato extracts had lower ferrous metal ion chelating effect than the white potato. A significant (P<0.05) positive correlation was observed between total polyphenol content and total flavonoid content (r=0.919), anthocyanin content (r=0.992), and ABTS radical scavenging activity (r=0.897). Based on these results, this research may be useful in developing the Hongyoung and Jayoung cultivars with high antioxidant activities.

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

Science.gov (United States)

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.

Plasma total anti-oxidant capacity correlates inversely with the extent of acute appendicitis: a case control study

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Devay Seda

2006-03-01

Full Text Available Abstract Background The role of free oxygen radicals in inflammatory conditions is well known. Free radicals cause lipid peroxidation of cellular membranes resulting in cell death. The purpose of this study was to investigate the levels of total anti-oxidant status (TAS, as a marker of anti-oxidant defense system and malondialdehyde (MDA, as a marker of oxidative stress, in the plasma of patients with acute appendicitis. Methods Fifty-one adult patients with a median age of 31 years who underwent operations with a preoperative diagnosis of acute appendicitis were included in this prospective study. Blood samples for C-reactive protein (CRP, MDA and TAS were collected preoperatively. Groups were compared by using the Mann-Whitney U test. Results There were 27 patients with acute phlagmenous appendicitis and 19 patients with advanced appendicitis (10 gangrenous and 9 perforated appendicitis, while 5 negative explorations were documented. No significant differences in WBC counts and MDA levels between groups were encountered. Plasma CRP was significantly higher in patients with perforated appendicitis, but not in the other groups. In advanced appendicitis group, TAS level was significantly lower than the other groups. On the other hand, plasma TAS level in acute phlagmenous appendicitis group was significantly higher. Conclusion A decrease in plasma total anti-oxidant capacity might be a predictor of the progression of inflammation to the perforation in acute appendicitis.

Spin trapping of cyanoalkyl radicals in the liquid phase γ radiolysis of nitriles

International Nuclear Information System (INIS)

Mao, S.W.; Kevan, L.

1976-01-01

The following radicals have been identified in the liquid phase γ radiolysis of several nitriles by spin trapping with phenyl tert-butyl nitrone: CH 2 CN in acetonitrile, H and CH 3 CHCN(question) in propionitrile, CH(CN) 2 in malononitrile, and H, CN, and CH 2 CH 2 CN in succinonitrile. γ proton splittings are observed for the CH 2 CN and CH(CH) 2 spin adducts. The results are discussed in comparison with solid phase radiolysis data and with alkyl radical spin adduct splittings

Effects of Ephedras Herba on the activity of antioxidant

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Seong-Min Song

2007-06-01

Full Text Available Objectives : The purpose of this study was to investigate the antioxidative effects of Ephedrae Herba extract. Methods : Total antioxidant status was examined by total antioxidant capacity(TAC, total antioxidant response(TAR against potent free radical reactions, total phenolic content, DPPH radical scavenging activities, and the inhibitory effect of the extract on lipid peroxidation in rat liver mitochondria. Results : 1. TAC and TAR of Ephedrae Herba extract at the concentration of 5mg/ml were 3.76 and 1.65 mM Trolox equivalents , respectively. 2. Total phenolic content of Ephedrae Herba extract at the concenuation of 5mg/ml was 3.52 mM gallic acid equivalent. 3. Concentration of Ephedrae Herba extract at which DPPH radical scavenging activity was inhibited by 50% was 0.46mg/ml as compared to 100% by pyrogallol solution as a reference. 4. Ephedrae Herba extract at the concentration of 2mg/ml significantly decreased TBARS concentration by 97%, showing that Ephedrae Herba extract prevented lipid peroxidation at the low concentration. Conclusion : Thus antioxidant effects of Ephedrae Herba extract appear to be due to, at least in part, the prevention from free radicalsinduced oxidation, followed by inhibition of lipid peroxidation

Total phenols and antioxidant activities of leaf and stem extracts from coriander, mint and parsley grown in Saudi Arabia

International Nuclear Information System (INIS)

Al-Juhaimi, F.; Ghafoorr, K.

2011-01-01

Leaves and stems of three different herbs from two different families were used to extract phenolic compounds and the bioactivity of the extracts was evaluated by using 1, 1-diphenyl-2-picrylhydrazyl or DPPH scavenging ability or their antioxidant activities. Extract from leaves of mint, which belongs to Lamiaceae family contained 1.24 mgGAE/100 mL of total phenolic compounds and 34.21% antioxidant activity which were significantly higher than those in extracts from coriander and parsley, both of which belong to Apiaceae family. Extracts of leaves from these herbs showed more quantity of total phenols and higher antioxidant activities than extracts from stem parts, however both leaves and stems of these three herbs grown in Saudi Arabia contained good quantities of total phenols (>1.02 mgGAE/100 mL) and showed more than 18.3% free radical scavenging activity. (author)

Role of the reacting free radicals on the antioxidant mechanism of curcumin

Energy Technology Data Exchange (ETDEWEB)

Galano, Annia, E-mail: agalano@prodigy.net.mx [Universidad Autonoma Metropolitana-Iztapalapa, Departamento de Quimica, Area de Quimica Analitica, San Rafael Atlixco 186, Col. Vicentina, Iztapalapa, C.P. 09340, Mexico D.F. (Mexico); Alvarez-Diduk, Ruslan; Ramirez-Silva, Maria Teresa; Alarcon-Angeles, Georgina; Rojas-Hernandez, Alberto [Universidad Autonoma Metropolitana-Iztapalapa, Departamento de Quimica, Area de Quimica Analitica, San Rafael Atlixco 186, Col. Vicentina, Iztapalapa, C.P. 09340, Mexico D.F. (Mexico)

2009-09-18

Density functional theory is used to study the antioxidant mechanism of curcumin. Five different mechanisms are considered: single electron transfer (SET), radical adduct formation (RAF), H atom transfer from neutral curcumin (HAT), H atom transfer from deprotonated curcumin (HAT-D), and sequential proton loss electron transfer (SPLET). The influence of the environment is investigated for polar and non-polar surroundings. The apparent contradictions among previous experimental results are explained by the role of the nature of the reacting free radical on the relative importance of the above mentioned mechanism. It is proposed that the curcumin + DPPH reaction actually takes place mainly through the SPLET mechanism, while the reaction with {sup {center_dot}}OCH{sub 3}, and likely with other alkoxyl radicals, is governed by the HAT mechanism. Branching ratios for the {sup {center_dot}}OCH{sub 3} + curcumin reaction are reported for the first time. The calculated overall rate constants for this reaction are 1.16 x 10{sup 10} (benzene) and 5.52 x 10{sup 9} (water) L mol{sup -1} s{sup -1}. The role of phenolic groups on the antioxidant activity of curcumin has been experimentally confirmed.

Unusual spin-trap chemistry for the reaction of hydroxyl radical with the carcinogen N-nitrosodimethylamine

Science.gov (United States)

Wink, David A.; Desrosiers, Marc F.

The reaction of the potent carcinogen N-nitrosodimethylamine (NDMA) with hydroxyl radical generated via radiolysis was studied using EPR techniques. Attempts to spin trap NDMA radical intermediates with 3,5-dibromo-4-nitrosobenzene sulfonate (DBNBS) produced only unusual DBNBS radicals. One of these radicals was shown to be generated by both reaction of DBNBS with nitric oxide, and direct oxidation of DBNBS with an inorganic oxidant ( .Br -2). Another DBNBS radical was identified as a sulfite spin adduct resulting from the degradation of DBNBS by a NDMA reactive intermediate. In the absence of DBNBS, hydroxyl radical reaction with NDMA gave the dimethylnitroxide radical. Unexpectedly, addition of DBNBS to a solution containing dimethylnitroxide produced an EPR spectrum nearly identical to that of NDMA solutions with DBNBS added before radiolysis. A proposed mechanism accounting for these observations is presented.

Unusual spin-trap chemistry for the reaction of hydroxyl radical with the carcinogen N-nitrosodimethylamine

Energy Technology Data Exchange (ETDEWEB)

Wink, D A [National Cancer Inst., Frederick, MD (United States); Desrosiers, M F [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

1991-01-01

The reaction of the potent carcinogen N-nitrosodimethylamine (NDMA) with hydroxyl radical generated via radiolysis was studied using EPR techniques. Attempts to spin trap NDMA radical intermediates with 3.5-dibromo-4-nitrosobenzene sulfonate (DBNBS) produced only unusual DBNBS radicals. One of these radicals was shown to be generated by both reaction of DBNBS with nitric oxide, and direct oxidation of DBNBS with an inorganic oxidant (BR{sub 2}{sup -}). Another DBNBS radical was identified as a sulfite spin adduct resulting from the degradation of DBNBS by a NDMA reactive inter-mediate. In the absence of DBNBS, hydroxyl radical reaction with NDMA gave the dimethylnitroxide produced an EPR spectrum nearly identical to that of NDMA solutions with DBNBS added before radiolysis. A proposed mechanism accounting for these observations is presented. (author).

Unusual spin-trap chemistry for the reaction of hydroxyl radical with the carcinogen N-nitrosodimethylamine

International Nuclear Information System (INIS)

Wink, D.A.; Desrosiers, M.F.

1991-01-01

The reaction of the potent carcinogen N-nitrosodimethylamine (NDMA) with hydroxyl radical generated via radiolysis was studied using EPR techniques. Attempts to spin trap NDMA radical intermediates with 3.5-dibromo-4-nitrosobenzene sulfonate (DBNBS) produced only unusual DBNBS radicals. One of these radicals was shown to be generated by both reaction of DBNBS with nitric oxide, and direct oxidation of DBNBS with an inorganic oxidant (BR 2 - ). Another DBNBS radical was identified as a sulfite spin adduct resulting from the degradation of DBNBS by a NDMA reactive inter-mediate. In the absence of DBNBS, hydroxyl radical reaction with NDMA gave the dimethylnitroxide produced an EPR spectrum nearly identical to that of NDMA solutions with DBNBS added before radiolysis. A proposed mechanism accounting for these observations is presented. (author)

Total phenolic and phytosterol compounds and the radical scavenging activity of germinated Australian sweet lupin flour.

Science.gov (United States)

Rumiyati; Jayasena, Vijay; James, Anthony P

2013-12-01

In addition to their favourable nutritional profile, legumes also contain a range of bioactive compounds such as phenolic compounds and phytosterols which may protect against chronic diseases including cancer and cardiovascular disease. Germination of some legume seeds has been previously reported to increase the concentration of the bioactive compounds. In this study, the effect of germination of Australian Sweet Lupin (ASL) seeds for 9 days on the concentration of some bioactive compounds and the radical scavenging activity in the resulting flour was determined. The concentration of total phenolic compounds in methanolic extracts of germinated ASL flour was determined using Folin Ciocalteu reagent and phytosterols in oil extracts were analyzed by gas-liquid chromatography. The methanolic and oil extracts were also used to determine radical scavenging activity toward 2,2-diphenyl-1-picrylhydrazyl. In the methanolic extracts of germinated ASL flour, phenolic contents and the antioxidant activity were significantly increased following germination (700 and 1400 %, respectively). Analysis of the oil extracts of germinated ASL flour revealed that the concentration of phytosterols and the antioxidant activity were also increased significantly compared to ungerminated ASL flour (300 and 800 %, respectively). The relative proportion of phytosterols in germinated ASL flour was: β-sitosterol (60 %), stigmasterol (30 %) and campesterol (10 %). Germination increases the concentration of bioactive compounds and the radical scavenging activity in the germinated ASL flour.

Free radicals and lipid peroxidation mediated injury in burn trauma: the role of antioxidant therapy

International Nuclear Information System (INIS)

Horton, Jureta W.

2003-01-01

Burn trauma produces significant fluid shifts that, in turn, reduce cardiac output and tissue perfusion. Treatment approaches to major burn injury include administration of crystalloid solutions to correct hypovolemia and to restore peripheral perfusion. While this aggressive postburn volume replacement increases oxygen delivery to previously ischemic tissue, this restoration of oxygen delivery is thought to initiate a series of deleterious events that exacerbate ischemia-related tissue injury. While persistent hypoperfusion after burn trauma would produce cell death, volume resuscitation may exacerbate the tissue injury that occurred during low flow state. It is clear that after burn trauma, tissue adenosine triphosphate (ATP) levels gradually fall, and increased adenosine monophosphate (AMP) is converted to hypoxanthine, providing substrate for xanthine oxidase. These complicated reactions produce hydrogen peroxide and superoxide, clearly recognized deleterious free radicals. In addition to xanthine oxidase related free radical generation in burn trauma, adherent-activated neutrophils produce additional free radicals. Enhanced free radical production is paralleled by impaired antioxidant mechanisms; as indicated by burn-related decreases in superoxide dismutase, catalase, glutathione, alpha tocopherol, and ascorbic acid levels. Burn related upregulation of inducible nitric oxide synthase (iNOS) may produce peripheral vasodilatation, upregulate the transcription factor nuclear factor kappa B (NF-κB), and promote transcription and translation of numerous inflammatory cytokines. NO may also interact with the superoxide radical to yield peroxynitrite, a highly reactive mediator of tissue injury. Free radical mediated cell injury has been supported by postburn increases in systemic and tissue levels of lipid peroxidation products such as conjugated dienes, thiobarbituric acid reaction products, or malondialdehyde (MDA) levels. Antioxidant therapy in burn therapy

Free radical generation by non-equilibrium atmospheric pressure plasma in alcohol-water mixtures: an EPR-spin trapping study

Science.gov (United States)

Uchiyama, Hidefumi; Ishikawa, Kenji; Zhao, Qing-Li; Andocs, Gabor; Nojima, Nobuyuki; Takeda, Keigo; Krishna, Murali C.; Ishijima, Tatsuo; Matsuya, Yuji; Hori, Masaru; Noguchi, Kyo; Kondo, Takashi

2018-03-01

Free radical species in aqueous solution—various alcohol-water reaction mixtures—by exposure to non-equilibrium cold atmospheric pressure Ar plasma (CAP), were monitored using electron paramagnetic resonance spin-trapping techniques with 3, 5-dibromo-4-nitrosobenzene sulfonate as a water soluble nitroso spin trap. The major radical species were formed by H-abstraction from alcohol molecules due to ·OH radicals. In the ethanol-water mixture ·CH2CH2OH produced by H abstraction from CH3 group of the ethanol and ·CH3 radicals were detected. The latter was due to the decomposition of unstable CH3·CHOH to form the ·CH3 radicals and the stable formaldehyde by C-C bond fission. These intermediates are similar to those observed by reaction with ·OH radicals generation in the H2O2-UV photolysis of the reaction mixtures. The evidence of ·CH3 radical formation in the pyrolytic decomposition of the reaction mixtures by exposure to ultrasound or in methane irradiated with microwave plasma have been reported previously. However, the pyrolytic ·CH3 radicals were not found in both plasma and H2O2-UV photolysis condition. These results suggests that free radicals produced by Ar-CAP are most likely due to the reaction between abundant ·OH radicals and alcohol molecules.

Free radical generation induced by ultrasound in red wine and model wine: An EPR spin-trapping study

OpenAIRE

Zhang, Quing An; Shen, Yuan; Fan, Xue-Hui; García-Martín, Juan Francisco; Wang, Xi; Song, Yun

2015-01-01

© 2015 Published by Elsevier B.V. Direct evidence for the formation of 1-hydroxylethyl radicals by ultrasound in red wine and air-saturated model wine is presented in this paper. Free radicals are thought to be the key intermediates in the ultrasound processing of wine, but their nature has not been established yet. Electron paramagnetic resonance (EPR) spin trapping with 5,5-dimethyl-l-pyrrolin N-oxide (DMPO) was used for the detection of hydroxyl free radicals and 1-hydroxylethyl free radic...

Effects of Puerariae Radix extract on the activity of antioxidant

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Young-Joon Eun

2007-12-01

Full Text Available Objective : The objective of this study was to investigate the antioxidative effects of Puerariae Radix extract. Method : Total antioxidant capacity (TAC, Total antioxidant response (TAR, Total phenolic content, Reactive oxygen species (ROS, 1,1-Diphenyl-2-picrylhydrazyl (DPPH free radical scavenging activities, lipid peroxidation were examined. Result : Total antioxidant status was examined by total antioxidant capacity(TAC and total antioxidant response(TAR against potent free radical reactions. TAC and TAR of Puerariae Radix extract at the concentration of 5 mg/㎖ were 2.02 and 1.50 mM Trolox equivalents, respectively. Total phenolic content of Puerariae Radix extract at the concentration of 5mg/㎖ was 2.29 mM gallic acid equivalent. Concentration of Puerariae Radix extract at which DPPH radical scavenging activity was inhibited by 50% was 5.91 mg/㎖ as compared to 100% by pyrogallol solution as a reference. The inhibitory effect of the extract on lipid peroxidation was examined using rat liver mitochondria induced by FeSO4/ascorbic acid. Puerariae Radix extract at the concentration of 1 mg/㎖ slightly but significantly decreased TBARS concentration. The extract further prevented lipid peroxidation in a dose-dependent manner. The effect of Puerariae Radix extract on reactive oxygen species (ROS generation was examined using cell-free system induced by hydrogen peroxide/FeSO4. Addition of 1 mg/㎖ of Puerariae Radix extract significantly reduced dichloroflurescein (DCF fluorescence. The extract caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that the extract significantly prevented ROS generation in vitro. Thus antioxidant effects of Puerariae Radix extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation, followed by inhibition of lipid peroxidation. Conclusion : As a result, Puerariae Radix seems to have antioxitative effect and antioxidant compount.

Effect of climate change on phytochemical diversity, total phenolic content and in vitro antioxidant activity of Aloe vera (L.) Burm.f.

Science.gov (United States)

Kumar, Sandeep; Yadav, Amita; Yadav, Manila; Yadav, Jaya Parkash

2017-01-25

The aim of the present study was to analyse the effect of climate change on phytochemicals, total phenolic content (TPC) and antioxidant potential of methanolic extracts of Aloe vera collected from different climatic zones of the India. Crude methanolic extracts of A. vera from the different states of India were screened for presence of various phytochemicals, total phenolic content and in vitro antioxidant activity. Total phenolic content was tested by Folin-Ciocalteau reagent based assay whilst DPPH free radical scavenging assay, metal chelating assay, hydrogen peroxide scavenging assay, reducing power assay and β carotene-linoleic assay were used to assess the antioxidant potential of A. vera methanolic leaf extracts. Alkaloids, phenols, flavonoids, saponins, and terpenes were the main phytochemicals presents in all accessions. A significant positive correlation was found between TPC and antioxidant activity of different accessions. Extracts of highland and semi-arid zones possessed maximum antioxidant potential. Accessions from tropical zones showed the least antioxidant activity in all assays. It could be concluded that different agro-climatic conditions have effects on the phytochemicals, total phenolic content (TPC) and antioxidant potential of the A. vera plant. The results reveal that A. vera can be a potential source of novel natural antioxidant compounds.

IN VITRO ANTIOXIDANT, TOTAL PHENOLIC AND FLAVONOID CONTENTS OF SIX ALLIUM SPECIES GROWING IN EGYPT

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Mahfouz Abdel-Gawad

2014-02-01

Full Text Available This study was designated to determine the total phenolic and flavonoid contents as well as evaluation the in vitro antioxidant activity of the defatted methanolic extracts of six Allium species growing in Egypt. Three of them are subspecies of Allium cepa L. (ssp. red onion, ssp. white onion and ssp. green onion, the other three species are Allium sativum L. (garlic, Allium porrum L. (leek and Allium kurrat L. (kurrat baladi. The results exhibited that A. cepa (ssp. red onion and A. porrum have the highest phenolic contents. On the other hand, in vitro antioxidant activity using three methods, 1, 1-diphenyl-2-picrylhydrazyl (DPPH radical, phosphomolybdate and reducing power assays revealed that A. cepa (ssp. red onion and A. porrum have high antioxidant activities. Moreover, there was positive correlation between the antioxidant activity and total phenolic contents of the tested Allium species. Therefore, the two plant species A. cepa (ssp. red onion and A. porrum were submitted to fractionation process using chloroform, ethyl acetate and n-butanol. The results showed that the ethyl acetate fractions of the two plants have high phenolic and flavonoid contents as well as have high antioxidant activities. Also, the preliminary phytochemical screening of the tested Allium species showed that A. cepa (ssp. red onion and A. porrum have high quantities of flavonoids, steroids, terpenoids and saponins.

Total Phenol Content and In Vitro Antioxidant Potential of Helicanthus elastica (Desr. Danser-A Less-explored Indian Mango Mistletoe

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Koppala Narayana Sunil Kumar

2014-10-01

Full Text Available Natural products are an important source of antioxidant molecules like tannins, phenolic compounds, flavonoids, etc., Helicanthus elastica (Desr. Danser (Loranthaceae is one such plant belonging to the category of mistletoe, and grows commonly on the mango trees in India. In the present study, an attempt has been made to assess the antioxidant properties of the plant. Ethanol extract of H. elastica growing on mango tree was studied using different in vitro models. Shade-dried whole plant material was extracted with ethanol by cold percolation. Fifty milligrams of the alcohol extract of H. elastica was weighed and dissolved in 10 ml of methanol. The resultant 5 mg/ml solution was suitably diluted to obtain different concentrations. Total phenol content, reducing power assay, and scavenging of free radicals like nitric oxide, hydroxyl, hydrogen peroxide, and 1,1-diphenyl-2-picrylhydrazyl were studied by standardized in vitro chemical methods using ascorbic acid as the standard. The total phenol content of the plant was found to be 1.89% w/w. The extract showed good reducing power as well as scavenging of free radicals (nitric oxide, hydroxyl, superoxide anion, and hydrogen peroxide at concentrations ranging from 5 to 100 μg/ml. The study revealed the antioxidant potential of H. elastica.

Synthesis and chain-breaking antioxidant activity of 6-amino-3-pyridinols and photochemistry of CdSe nanocrystals covered with functionalized cinnamates

NARCIS (Netherlands)

Wijtmans, Maikel

2004-01-01

Antioxidants are Nature's primary defense against lipid peroxidation, a process believed to be involved in a range of diseases such as atherosclerosis, cancer, Parkinson's and Alzheimer disease, and others. The best antioxidant Nature has is Vitamin E and it serves to trap free radicals, which are

Total antioxidant capacity in children with acute appendicitis.

Science.gov (United States)

Kaya, M; Boleken, M E; Kanmaz, T; Erel, O; Yucesan, S

2006-02-01

This study aimed to investigate antioxidant capacity by using a novel automated method in children with acute appendicitis. Blood samples were obtained from consecutive patients with acute appendicitis (appendicitis group, n = 12) and acute abdominal pain due to non surgical disease (non-appendicitis group, n = 11), and from patients with inguinal hernia (healthy group, n = 12) as the control group. At admission, total antioxidant capacity (TAC) levels of plasma were evaluated in all patients by a method recently developed by Erel. Four other major individual plasma antioxidant components, the levels of total protein, albumin, uric acid and bilirubin, were also evaluated. Total antioxidant capacity in patients with acute appendicitis was statistically compared with the two other groups. While the TAC level in the appendicitis group was significantly greater than in the non-appendicitis group, no significant difference was found in healthy groups (p 0.05, 1.94 +/- 0.38, 1.40 +/- 0.36, and 1.99 +/- 0.35 respectively). Individual components of total antioxidant capacity, i.e. total protein, albumin, uric acid and bilirubin concentrations, were also higher in the patients with acute appendicitis than those of the other two control groups. Our data show that children with acute appendicitis do not have deficient blood plasma antioxidant capacity. These results provide evidence that acute appendicitis results in more induction of antioxidative response than non-surgical diseases.

Effect of vitamin C and E supplementation on total antioxidant content of human breastmilk and infant urine.

Science.gov (United States)

Zarban, Asghar; Toroghi, Mahsa Mostafavi; Asli, Marziye; Jafari, Masumeh; Vejdan, Morteza; Sharifzadeh, Gholamreza

2015-05-01

After delivery and birth, mothers and neonates are exposed to oxidative stress. The present study examined the effect of supplementation of the diet of breastfeeding mothers with vitamin C and E to improve the antioxidant content of breastmilk and evidence of antioxidant activity in infant urine. The subjects were 60 healthy lactating breastfeeding mothers and their infants 1-6 months of age. They were randomly allocated to a control group (n=30) consuming a free diet or an experimental group (n=30) consuming a free diet supplemented each day with effervescent tablets of vitamin C (500 mg) and chewable tablets of vitamin E (100 IU). After 30 days, the total antioxidant content of the mothers' breastmilk and evidence of antioxidant activity in the infants' urine were measured by the ferric reducing/antioxidant power assay. The free radical scavenging activity of the urine samples was measured by the α,α-diphenyl-β-picrylhydrazyl method. Differences pre- and postintervention were compared within and between the groups. Significantly higher levels of antioxidants in the breastmilk (610±295.5 to 716±237.5 μmol/L) and infant urine (43.2±21.8 to 75.0±49.2 μmol/mg creatinine) were observed in the experimental group over the control group (pvitamin C and E supplements appears to have a positive effect on total antioxidant content of breastmilk and evidence of antioxidant activity in infant urine.

Assessment of antioxidant activity of cane brown sugars by ABTS and DPPH radical scavenging assays: determination of their polyphenolic and volatile constituents.

Science.gov (United States)

Payet, Bertrand; Shum Cheong Sing, Alain; Smadja, Jacqueline

2005-12-28

Seven cane brown sugars (four from La Réunion, two from Mauritius, and one from France) were investigated for their polyphenol content and volatile composition in relation to their free radical scavenging capacity determined by ABTS and DPPH assays. The thin layer coated on the sugar crystal was extracted by Soxhlet extractor with dichloromethane. The volatile compounds of brown sugars were studied by GC-MS, and 43 compounds were identified. The total phenolic content of brown sugars was determined according to the Folin-Ciocalteu method. Phenolic compounds were quantified in the brown sugar extracts by LC-UV-ESI-MS. Brown sugar aqueous solutions exhibited weak free radical scavenging activity in the DPPH assay and higher antioxidant activity in the ABTS assay at relatively high concentration. The brown sugar extracts showed interesting free radical scavenging properties despite the low concentration of phenolic and volatile compounds. Sugar is a common foodstuff traditionally used for its sweetening properties, which might be accompanied by antioxidant properties arising from molecules (polyphenols, Maillard products) other than sucrose of the cane brown sugars.

Appraisal of Total Phenol, Flavonoid Contents, and Antioxidant Potential of Folkloric Lannea coromandelica Using In Vitro and In Vivo Assays

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Tekeshwar Kumar

2015-01-01

Full Text Available The aim of this study was to determine the impending antioxidant properties of different extracts of crude methanolic extract (CME of leaves of Lannea coromandelica (L. coromandelica and its two ethyl acetate (EAF and aqueous (AqF subfractions by employing various established in vitro systems and estimation of total phenolic and flavonoid content. The results showed that extract and fractions possessed strong antioxidant activity in vitro and among them, EAF had the strongest antioxidant activity. EAF was confirmed for its highest phenolic content, total flavonoid contents, and total antioxidant capacity. The EAF was found to show remarkable scavenging activity on 2,2-diphenylpicrylhydrazyl (DPPH (EC50 63.9 ± 0.64 µg/mL, superoxide radical (EC50 8.2 ± 0.12 mg/mL, and Fe2+ chelating activity (EC50 6.2 ± 0.09 mg/mL. Based on our in vitro results, EAF was investigated for in vivo antioxidant assay. Intragastric administration of the EAF can significantly increase levels of superoxide dismutase (SOD, catalase (CAT, glutathione (GSH, and glutathione peroxidase (GSH-Px levels, and decrease malondialdehyde (MDA content in the liver and kidney of CCl4-intoxicated rats. These new evidences show that L. coromandelica bared antioxidant activity.

In vitro free radical scavenging activity of Ixora coccinea L

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Moni Rani Saha

2008-06-01

Full Text Available Antioxidant activity of the methanol extract of Ixora coccinea L. was determined by DPPH free radical scavenging assay, reducing power and total antioxidant capacity using phosphomolybdenum method. Preliminary phytochemical screening revealed that the extract of the flower of I. coccinea possesses flavonoids, steroids and tannin materials. The extract showed significant activities in all antioxidant assays compared to the standard antioxidant in a dose dependent manner and remarkable activities to scavenge reactive oxygen species (ROS may be attributed to the high amount of hydrophilic phenolics. In DPPH radical scavenging assay the IC50 value of the extract was found to be 100.53 μg/mL while ascorbic acid had the IC50 value 58.92 μg/mL. Moreover, I. coccinea extract showed strong reducing power and total antioxidant capacity.

Effect of drying techniques on the retention of antioxidant activities of Saskatoon berries

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Pranabendu Mitra

2013-10-01

Full Text Available The main objective of this research was to compare the retention of antioxidant activity and total anthocyanin content of Saskatoon berries dried by freeze drying, microwave-vacuum drying, thin layer hot air drying and vacuum drying. Antioxidant activity of berry samples was determined by DPPH radical scavenging and ABTS radical scavenging, and the pH differential method was used to determine total anthocyanin content of the berry samples. The results showed that the freeze dried Saskatoon berries exhibited the highest retention of anthocyanin and antioxidant activity among the dried samples, followed by microwave-vacuum dried berries, thin layer hot air dried berries and vacuum dried berries. There were significant differences between the berry samples at P<0.05.  DPPH radical scavenging and ABTS radical scavenging were correlated linearly with an R2 value of 0.99 at P<0.05 showing their effectiveness for the determination of the antioxidant activity of the Saskatoon berries. However, the DPPH radical scavenging assay was more effective than the ABTS radical scavenging assay. The results also showed that antioxidant activity of the berries was highly correlated with the total anthocyanin content of the fruit. The reduction of anthocyanin in dried berry samples was linearly correlated with the reduction of DPPH radical scavenging with an R2 value of 0.97 at P<0.05 and, also, linearly correlated with the reduction of ABTS radical scavenging with an R2 value of 0.88 at P<0.05.

Investigating free radical generation in HepG2 cells using immuno-spin trapping.

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Horinouchi, Yuya; Summers, Fiona A; Ehrenshaft, Marilyn; Kawazoe, Kazuyoshi; Tsuchiya, Koichiro; Tamaki, Toshiaki; Mason, Ronald P

2014-10-01

Oxidative stress can induce the generation of free radicals, which are believed to play an important role in both physiological and pathological processes and a number of diseases such as cancer. Therefore, it is important to identify chemicals which are capable of inducing oxidative stress. In this study, we evaluated the ability of four environmental chemicals, aniline, nitrosobenzene (NB), N,N-dimethylaniline (DMA) and N,N-dimethyl-4-nitrosoaniline (DMNA), to induce free radicals and cellular damage in the hepatoma cell line HepG2. Cytotoxicity was assessed using lactate dehydrogenase (LDH) assays and morphological changes were observed using phase contrast microscopy. Free radicals were detected by immuno-spin trapping (IST) in in-cell western experiments or in confocal microscopy experiments to determine the subcellular localization of free radical generation. DMNA induced free radical generation, LDH release and morphological changes in HepG2 cells whereas aniline, NB and DMA did not. Confocal microscopy showed that DMNA induced free radical generation mainly in the cytosol. Preincubation of HepG2 cells with N-acetylcysteine and 2,2'-dipyridyl significantly prevented free radical generation upon subsequent incubation with DMNA, whereas preincubation with apocynin and dimethyl sulfoxide did not. These results suggest that DMNA induces oxidative stress and that reactive oxygen species, metals and free radical generation play a critical role in DMNA-induced cytotoxicity. Copyright © 2014. Published by Elsevier Inc.

Antioxidant activity, total phenolic, and total flavonoid of extracts from stems of Jasminum nervosum Lour

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Wei, Xiangyong

2011-06-01

Full Text Available Guangxi traditional Chinese Medical University Universidad de Medicina Tradicional China de Guangxi This study evaluated the antioxidant activities of the extracts of Jasminum nervosum Lour. stems along with the effects of different extract solvents on total phenolics (TP, total flavonoids (TF, and antioxidant potential. The antioxidant activity of the extracts was assessed using the following methods: DPPH, ABTS+ both free radicals scavenging assays, and reducing assays. TP and TF were detected by spectrophotometric and HPLC methods. In former methods, the highest amount of TP content was ethy lacetate extract (EAE, expressed as gallic acid equivalents. The greatest TF content was in the n-butanol extract (BE, expressed as lutin equivalents. No significant difference was observed in the TP/TF content between these two extracts. The antioxidant activity and TP/TF content of three extracts seemed to follow the same trend. This implied that there is a good correlation between antioxidant activities and TP/TF content. But in HPLC methods, EAE contained the highest content of lutin and gallic acid, which decreased in the same order of EAE > BE > PE, the rank order of TP/TF content of EAE and BE were different according to antioxidant ability. The overall results showed that the EAE and BE were richer in phenolics and flavonoids than petroleum ether extract (PE, and may represent a good source of antioxidants.Este estudio evaluó las actividades antioxidantes de extractos de tallos de Jasminum nervosum Lour., y el efecto de diferentes disolventes de extracción en los fenoles totales (TP y flavonoides totales (TF, y su potencial antioxidante. La actividad antioxidante de los extractos fue evaluada usando los siguientes métodos: DPPH, ABTS+ y ensayos reductores. TP y TF fueron detectados por métodos espectroscópicos y por HPLC. Con el primer método, el contenido más alto de TP se obtuvo en el extracto con acetato de etilo (EAE, expresado como

Effect of hydrothermal processing on total polyphenolics and antioxidant potential of underutilized leafy vegetables, Boerhaavia diffusa and Portulaca oleracea

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Nagarani, Gunasekaran; Abirami, Arumugam; Nikitha, Prasad; Siddhuraju, Perumal

2014-01-01

Objective To investigate the effect of different processing methods on antioxidant properties of acetone extract of aerial parts from Boerhaavia diffusa and Portulaca oleracea. Methods The total phenolic and flavonoid contents were determined by Folin-Ciocalteau and aluminum chloride method, respectively. FRAP, metal chelating activity, DPPH, ABTS, nitric oxide, hydroxyl and superoxide radical scavenging activities, carotene/linoleic acid bleaching activity were used for the determination of antioxidant capacity. Results The total phenolics in Boerhaavia diffusa (82.79-162.80 mg GAE/g extract) were found to be higher when compared to that of Portulaca oleracea (22.94-10.02 mg GAE/g extract). Hydrothermal processing enhanced the level of inhibition on synthetic radicals such as DPPH (3 439-309 549 mmol TE/g extract) and ABTS (17 808-53 818 mmol TE/g extract) as well as biologically relevant radicals such as superoxide anion (70%-90%) and nitric oxide (49%-57%). In addition, boiling of the vegetables were found to be maximum capacity of FRAP (6 404.95 mmol Fe (II)/g extract) and metal chelating activity (1.53 mg EDTA/g extract) than the respective raw samples. Conclusions The present investigation suggests that the processing enhance the functionality and improves the availability of bioactive substances of these vegetables. In addition, they also exhibited more potent antioxidant activity. Therefore these natural weeds from the crop land ecosystem could be suggested as cost effective indigenous green vegetables for human diet and potential feed resources for animals. Further extensive studies on role and importance of those weeds in sustaining the agro biodiversity are also needed. PMID:25183131

Phytochemical screening, total phenolic, total flavonoids contents and antioxidant activity of cinchona ledgeriana leaves ethanol extract

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Sundowo, Andini; Artanti, Nina; Hanafi, M.; Minarti, Primahana, Gian

2017-11-01

C ledgeriana is a medicinal plant that contains alkaloids, especially on the barks for commercial production of quinine as antimalarial. The main alkaloids in this plant are cinchonine, cinchonidine, quinine and quinidine. Besides for antiamalarial this plant is also commonly used to treat whooping cough, influenza and dysentery. Compare to other medicinal plants, nowadays only very few studies were conducted in Cinchona species. Our current study aims to determine the content of phytochemical, total phenol and total flavonoids from C. ledgeriana leaves 70% ethanol extract. The extraction was performed by maceration method using 70% ethanol solvent and then fractionated into hexane, ethylacetate and butanol. Phytochemical screening was performed to determine the content of alkaloids, flavonoids, terpenoids, tannins and saponins. Total phenol and flavonoid contents of the extract were determined by Folin-Ciocalteu and alumunium chloride colorimetric methods using gallic acid and quercetin as standards. The antioxidant activity was determined by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The results of phytochemical screening showed that the 70% ethanol extract of C. ledgeriana leaves contained alkaloids, flavonoids, terpenoids, tannins and saponins. The total phenol and total flavonoids analysis showed that ethyl acetate fraction had the highest total phenol (40.23%) and total flavonoids (65.34%).

Antioxidant activity of melatonin and glutathione interacting with hydroxyl- and superoxide anion radicals

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T. Y. Kuznetsova

2017-12-01

Full Text Available Based on the analysis of the results obtained by quantum chemical modeling of interaction between reduced glutathione (GSH and melatonin (MLT molecules with oxygen radicals (•OH and • OOˉ it was found that this interaction occured following the acid-base mechanism, where MLT and GSH acted as a base in respect of •OH, and as acid in respect of •OOˉ. We have carried out the correlation of the results of quantum chemical calculations (density redistribution, energetic characteristics under the interaction of MLT and GSH molecules with •OH and •OOˉ in changing macroscopic properties of the process of electroreduction of free oxygen radicals in the presence of antioxidants (potential and maximal current wave reduction waves. This was a direct experimental macroscale evidence of the results of theoretical modeling at the nanoscale level that pointed to a marked antioxidant activity of glutathione compared with melatonin.

A DFT study on the deprotonation antioxidant mechanistic step of ortho-substituted phenolic cation radicals

International Nuclear Information System (INIS)

Vafiadis, Anastasios P.; Bakalbassis, Evangelos G.

2005-01-01

The conformers of the 2-, 3- and 4-substituted phenolic cation radicals, 2-X-, 3-X- and 4-X-ArOH ·+ , and the respective phenoxyl radicals, ArO · , the intramolecular hydrogen bond strength (ΔH intra ) estimate along with the electronic effects of five electron withdrawing (EWG) and eight electron donating groups (EDG) on the gas-phase O-H proton dissociation enthalpies, (PDEs), of the short-lived, 2-X-ArOH ·+ , (involved in the single-electron transfer antioxidant mechanism), are studied at the DFT/B3LYP level of theory. EWG result to smaller PDEs, hence to stronger acidity; EDG to weaker acidity. The deprotonation antioxidant mechanistic step is not a rate-controlling step for 2-X-ArOH to scavenge free radicals. Approximate estimations of the ΔPDEs (hence acidities as well) can be derived from calculated structural and/or vibrational frequency values. ΔH intra s correlate reasonably with geometrical parameters for the closed-shell, neutral counterparts, in contrast with previous estimates

Total antioxidant content of alternatives to refined sugar.

Science.gov (United States)

Phillips, Katherine M; Carlsen, Monica H; Blomhoff, Rune

2009-01-01

Oxidative damage is implicated in the etiology of cancer, cardiovascular disease, and other degenerative disorders. Recent nutritional research has focused on the antioxidant potential of foods, while current dietary recommendations are to increase the intake of antioxidant-rich foods rather than supplement specific nutrients. Many alternatives to refined sugar are available, including raw cane sugar, plant saps/syrups (eg, maple syrup, agave nectar), molasses, honey, and fruit sugars (eg, date sugar). Unrefined sweeteners were hypothesized to contain higher levels of antioxidants, similar to the contrast between whole and refined grain products. To compare the total antioxidant content of natural sweeteners as alternatives to refined sugar. The ferric-reducing ability of plasma (FRAP) assay was used to estimate total antioxidant capacity. Major brands of 12 types of sweeteners as well as refined white sugar and corn syrup were sampled from retail outlets in the United States. Substantial differences in total antioxidant content of different sweeteners were found. Refined sugar, corn syrup, and agave nectar contained minimal antioxidant activity (sugar had a higher FRAP (0.1 mmol/100 g). Dark and blackstrap molasses had the highest FRAP (4.6 to 4.9 mmol/100 g), while maple syrup, brown sugar, and honey showed intermediate antioxidant capacity (0.2 to 0.7 mmol FRAP/100 g). Based on an average intake of 130 g/day refined sugars and the antioxidant activity measured in typical diets, substituting alternative sweeteners could increase antioxidant intake an average of 2.6 mmol/day, similar to the amount found in a serving of berries or nuts. Many readily available alternatives to refined sugar offer the potential benefit of antioxidant activity.

Studies of short-lived radicals in the. gamma. -irradiated aqueous solution of uridine-5'-monophosphate by the spin-trapping method and the liquid chromatography

Energy Technology Data Exchange (ETDEWEB)

Kominami, S [Hiroshima Univ. (Japan); Rokushika, S; Hatano, H

1976-12-01

An aerated aqueous solution of uridine-5'-monophosphate was ..gamma..-irradiated with 2-methyl-2-nitrosopropane as a spin-trapping reagent. Liquid chromatography was applied to separate the stable nitroxide radicals in the irradiated solution. The radicals were detected by U.V. and e.s.r. spectrometry. The e.s.r. detection showed four peaks in the chromatogram. The orcinol method for detection of the residual sugar moieties was applied before and after reduction of the base to determine the existence of the 5,6-double bond for the molecules in each fraction. From the combined results of the e.s.r. and orcinol methods, the short-lived radicals which were trapped by 2-methyl-2-nitrosopropane were identified as radicals of N-1 and C-6 positions of the base moiety and t-butyl radicals which was the radiolytic product of the trapping reagent.

Effect of ultrafine grinding on physicochemical and antioxidant properties of dietary fiber from wine grape pomace.

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Zhu, Feng-Mei; Du, Bin; Li, Jun

2014-01-01

Wine grape pomace dietary fiber powders were prepared by superfine grinding, whose effects were investigated on the composition, functional and antioxidant properties of the wine grape pomace dietary fiber products. The results showed that superfine grinding could effectively pulverize the fiber particles to submicron scale. As particle size decrease, the functional properties (water-holding capacity, water-retention capacity, swelling capacity, oil-binding capacity, and nitrite ion absorption capacity) of wine grape pomace dietary fiber were significantly (p fiber components from insoluble to soluble fractions was observed. The antioxidant activities of wine grape pomace and dietary fiber before and after grinding were in terms of DPPH radical scavenging activity, ABTS diammonium salt radical scavenging activity, ferric reducing antioxidant power, and total phenolic content. Compared with dietary fiber before and after grinding, micronized insoluble dietary fiber showed increased ABTS radical scavenging activity, ferric reducing antioxidant power, and total phenolic content yet decreased DPPH radical scavenging activity. Positive correlations were detected between ABTS radical scavenging activity, ferric reducing antioxidant power, and total phenolic content.

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

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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.

Antioxidative Activity of Colostrum and Human Milk: Effects of Pasteurization and Storage.

Science.gov (United States)

Marinković, Vesna; Ranković-Janevski, Milica; Spasić, Snežana; Nikolić-Kokić, Aleksandra; Lugonja, Nikoleta; Djurović, Dijana; Miletić, Srdjan; Vrvić, Miroslav M; Spasojević, Ivan

2016-06-01

Milk banks collect, pasteurize, and freeze/store human milk. The processing may alter redox properties of milk, but the effects have not been fully examined. We collected 10 mature milk and 10 colostrum samples and applied a battery of biochemical assays and electron paramagnetic resonance spectroscopy to inspect changes that milk undergoes with pasteurization and 30 days storage at -20°C. Pasteurization and storage of raw milk did not affect total nonenzymatic antioxidative capacity, but specific components and features were altered. Urate radical and ascorbyl radical emerge as products of exposure of milk to hydroxyl radical-generating system. Processing shifted the load of antioxidative activity from ascorbate to urate and lowered the capacity of milk to diminish hydroxyl radical. Pasteurization caused a significant drop in the activity of 2 major antioxidative enzymes-superoxide dismutase and glutathione peroxidase, whereas freezing/storage of raw milk affected only superoxide dismutase. Colostrum showed drastically higher total nonenzymatic antioxidative capacity, hydroxyl radical scavenging ability, and glutathione reductase activity compared with mature milk. Pasteurization and storage affect nonenzymatic and enzymatic antioxidative agents in human milk. It appears that nonenzymatic antioxidative systems in colostrum and milk are different. The effects of processing may be partially compensated by fortification/spiking with ascorbate before use.

Technological properties, antioxidant activity and total phenolic and flavonoid content of pigmented chickpea (Cicer arietinum L.) cultivars.

Science.gov (United States)

Heiras-Palazuelos, Mar J; Ochoa-Lugo, Mirna I; Gutiérrez-Dorado, Roberto; López-Valenzuela, José A; Mora-Rochín, Saraid; Milán-Carrillo, Jorge; Garzón-Tiznado, José A; Reyes-Moreno, Cuauhtémoc

2013-02-01

Chickpeas are rich sources of highly nutritious protein and dietary fibre; the health benefits of consuming legumes such as antioxidant activity (AoxA) could be effective for the expansion of their food uses. The technological properties and antioxidant potential of five pigmented chickpea cultivars were evaluated. Protein content of the grains varied from 24.9 to 27.4 g/100 g sample (dw). The cooking time (CT) of the whole grains ranged from 90.5 to 218.5 min; the lowest CT corresponded to Black ICC3761 cultivar. The total phenolic content (TPC) and AoxA [oxygen radical absorbance capacity (ORAC) value] varied from 1.23 to 1.51 mg GAE/g sample (dw) and from 5011 to 5756 μmol TE/100 g sample (dw), respectively; Red ICC13124 showed the highest ORAC value. The differences in technological properties and AoxA among cultivars could be used in chickpea breeding programmes. Chickpea cultivars could contribute significantly to the management and/or prevention of degenerative diseases associated with free radical damage.

Antioxidant and Anti-Osteoporosis Activities of Chemical Constituents of the Stems of Zanthoxylum piperitum

OpenAIRE

Seo Young Yang; Sang-Hyun Lee; Bui Huu Tai; Hae-Dong Jang; Young Ho Kim

2018-01-01

Two new lignans, zanthoxyloside C (1) and zanthoxyloside D (2), together with nine known compounds comprising lignans (3–5), flavonoids (6–8), and phenolics (9–11), were isolated from the methanol extract of the stems of Zanthoxylum piperitum. All isolates were evaluated for their antioxidant and anti-osteoporotic activities using oxygen radical absorbance capacity (ORAC), cupric reducing antioxidant capacity (CUPRAC), and tartrate-resistant acid phosphatase (TRAP) assays. Compounds 7–10 show...

Antioxidant capacity and total phenolic contents of oregano (Origanum vulgare), lavender (Lavandula angustifolia) and lemon balm (Melissa officinalis) from Romania.

Science.gov (United States)

Spiridon, Iuliana; Colceru, Svetlana; Anghel, Narcis; Teaca, Carmen Alice; Bodirlau, Ruxanda; Armatu, Alice

2011-10-01

The study reported here presents a comparative screening of three medicinal plants including oregano (Origanum vulgare L.), lavender (Lavandula angustifolia) and lemon balm (Melissa officinalis) having the same geographical origin, the Southeast region of Romania, and growing in the same natural conditions. The contents of total phenolics and total flavonoids for the extracts of these were determined. Furthermore, the total antioxidant capacity was also evaluated. It was found that Origanum vulgare and Melissa officinalis extracts present the most effective antioxidant capacity in scavenging DPPH radicals, while Lavandula angustifolia is less active. High performance liquid chromatography-mass spectrometry analysis was used to identify the components of extracts. Major phenolic acids identified in the analysed species were ferulic, rosmarinic, p-coumaric and caffeic, while predominant flavonoids were quercetin, apigenin kaempherol, which were present as glucosides.

Dose and time effect of CdTe quantum dots on antioxidant capacities of the liver and kidneys in mice

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Wang J

2017-09-01

Full Text Available Jilong Wang,1,2,* Hubo Sun,1,2,* Peijun Meng,1,2 Mengmeng Wang,1,2 Mi Tian,3 Yamin Xiong,1,2 Xueying Zhang,1,2 Peili Huang1,2 1School of Public Health, Capital Medical University, 2Beijing Key Laboratory of Environmental Toxicology, 3Medical Experiment and Test Center, Capital Medical University, Beijing, People’s Republic of China *These authors contributed equally to this work Abstract: Although quantum dot (QD-induced toxicity occurs due to free radicals, generation of oxidative stress mediated by reactive oxygen species (ROS formation is considered an important mechanism. However, free radical mechanisms are essentially difficult to elucidate at the molecular level because most biologically relevant free radicals are highly reactive and short-lived, making them difficult to directly detect, especially in vivo. Antioxidants play an important role in preventing or, in most cases, limiting the damage caused by ROS. Healthy people and animals possess many endogenous antioxidative substances that scavenge free radicals in vivo to maintain the redox balance and genome integrity. The antioxidant capacity of an organism is highly important but seldom studied. In this study, the dose and time effects of CdTe QDs on the antioxidant capacities of the liver and kidneys were investigated in mice using the electron paramagnetic resonance (EPR spin-trapping technique. We found that the liver and kidneys of healthy mice contain specific antioxidant capacities that scavenge ·OH and ·O2-. Furthermore, oxidative stress markers (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GPx], glutathione [GSH] and malondialdehyde [MDA] were examined. In dose course studies, the free radical scavenging efficiencies of the liver and kidneys were found to gradually decrease with increasing concentration of CdTe QD exposure. The activities and levels of SOD, CAT, GPx and MDA were observed to increase in treated groups, whereas those of GSH were reduced

Detection and characterisation of radicals using electron paramagnetic resonance (EPR) spin trapping and related methods

DEFF Research Database (Denmark)

Davies, Michael Jonathan

2016-01-01

Electron paramagnetic resonance (EPR) spectroscopy (also known as electron spin resonance, ESR, or electron magnetic resonance, EMR, spectroscopy) is often described as the “gold standard” for the detection and characterisation of radicals in chemical, biological and medical systems. The article...... reviews aspects of EPR spectroscopy and discusses how this methodology and related techniques can be used to obtain useful information from biological systems. Consideration is given to the direct detection of radicals, the use of spin traps and the detection of nitric oxide, and the advantages...

Comparing phenolics composition and antioxidant activities of different pomegranate products

International Nuclear Information System (INIS)

Wasila, H.; Li, X.; Liu, L.; Ahmad, I.

2014-01-01

The phenolics and antioxidant abilities of pomegranate juices (aril juice (aj) and aril-mesocarp-epicarp mixture juice (amej), by-product extracts (extract of aril-mesocarp-epicarp (eame) and rind extract (er) were determined and compared. The results showed no significant difference in phenolic compositions however ratio of phenolic constituent were found different. The total phenolics, total flavonoids and total tannins contents followed the order of er>eame>amej>aj, and total anthocyanins followed the trend eame>amej>aj>er. The total antioxidant, total reduction, abts o+ radical scavenging and dppho radical scavenging capacities followed the sequence r>aj>eame>amej, amej>er>eame>aj, er>amej>eame>aj and amej>er>aj>eame respectively. With the exception of abtso+ scavenging capacities, strongest antioxidant activity found in juices compared to their corresponding purified products. These data suggest that phenolics play a vital role in the composition and antioxidant activity of pomegranate products. (author)

Evaluation of nutritional quality and antioxidant potential of pigeonpea genotypes.

Science.gov (United States)

Sekhon, Japjot; Grewal, Satvir Kaur; Singh, Inderjit; Kaur, Jagmeet

2017-10-01

Three released cultivars, forty four advance breeding lines and three wild species of pigeonpea ( Cajanus cajan L. Millsp) were evaluated for nutritional, antinutritional traits and antioxidant potential so as to identify promising genotypes. The average content of total soluble sugars, starch and total soluble proteins was found to be 43.66, 360.51 and 204.54 mg/g, respectively. Antioxidant potential in terms of free radical scavenging activity (DPPH), ferric reducing antioxidant power (FRAP), reducing power, hydroxyl radical scavenging activity and superoxide anion radical scavenging activity was estimated. The diversity was observed in genotypes with all the traits. AL 1960, AL 2000, AL 2009 and AL 2046 had high total soluble proteins, medium antinutritional factors and good antioxidant potential. AL 201, AL 1931, AL 1932, AL 1960, AL 2046, AL 2049 and AL 2060 had good nutritional value as protein and starch content ranged from 20 to 23 and 42 to 52%, respectively. Wild species C. scarabaeoides 1CP15683/W15 had lower carbohydrates, proteins, and antinutritional traits while high antioxidant potential due to high total phenols, DPPH, FRAP and reducing power. The diversity observed in genotypes with all the traits could be further used to develop nutritionally important genotypes.

Relationship between vitamin intake and total antioxidant capacity in elderly adults

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Miriam Lucia Ojeda Arredondo

2016-06-01

Full Text Available The consumption of foods high in natural antioxidants, like fruits and vegetables, is associated with a lower risk of oxidative stress-related diseases. The aim of this study was to establish the relationship between the plasma antioxidant capacity in adults over fifty and their intake of vitamin A, C, and E. We evaluated 118 24-hour recalls of intake of foods. The intake of vitamin A, C, and E was quantified using food composition tables. We quantified plasma phenols using the Folin-Ciocalteu method. The antioxidant capacity was determined using the Trolox Equivalent Antioxidant Capacity (TEAC and Oxygen Radical Absorption Capacity (ORAC methods. Correlation analyses were performed between the studied variables and a positive correlation was found in most cases. However, none of the correlations was statistically significant. In all cases p-value was >0.05. The quantification of nutrient intake is not an adequate predictor of plasma antioxidant capacity in individuals over fifty

Antioxidant and Free Radical Scavenging Activity of Trigonella foenum-graecum L, Murraya koenigii , Coriandrum sativum and Centella asiatica

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Sanghamitra Dutta

2016-04-01

Full Text Available Antioxidants are naturally occurring substances that combat oxidative damage in biological entities. An antioxidant achieves this by slowing or preventing the oxidation process that can damage cells in the body. It does this by getting oxidized itself in place of the cells. The aim of the present study was to evaluate the in vitro antioxidant and free radical scavenging activities of aqueous and 95% methanol leaf extracts of four herbs viz. Trigonella foenum-graecum L, Murraya koenigii, Coriandrum sativum and Centella asiatica which have frequent use in Indian cuisine. Both aqueous and 95% methanol leaf extracts have shown significant amount reducing power. Both aqueous and 95% methanol leaf extracts of Coriandrum sativum had significant DPPH radical scavenging activity with IC50 value of 0.21± 0.3 mg/L and 0.176 ± 0.008 mg/L respectively. The aqueous leaf extract of Trigonella foenum-graecum L showed low scavenging activity. Among all the leaf extracts, the aqueous leaf extract of Centella asiatica has exhibited significantly high NO radical scavenging activity (80% with IC50 value of 0.11 ± 0.17 mg/L. The aqueous leaf extracts of the samples have showed significantly high superoxide radical scavenging activity. The activity was maximum for the aqueous leaf extract of Centella asiatica, IC50 value is 4.36 ± 0.41 mg/L. anti lipid peroxide activities were very high ( 90 % for aqueous leaf extracts of Coriandrum sativum (IC50 = 0.064 ± 0.85 mg/L and Centella asiatica (IC50 = 0.066 ± 0.9mg/L at a concentration of 0.16 mg/L. The aqueous leaf extracts of the samples were found to contain large amounts of flavonoids and phenolic compounds and exhibited high antioxidant and free radical scavenging activities. These in vitro assays indicate that these plant extracts are significant source of natural antioxidants which might be helpful in preventing the progress of various oxidative stresses.

OKN-007 decreases free radical levels in a preclinical F98 rat glioma model.

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Coutinho de Souza, Patricia; Smith, Nataliya; Atolagbe, Oluwatomisin; Ziegler, Jadith; Njoku, Charity; Lerner, Megan; Ehrenshaft, Marilyn; Mason, Ronald P; Meek, Bill; Plafker, Scott M; Saunders, Debra; Mamedova, Nadezda; Towner, Rheal A

2015-10-01

Free radicals are associated with glioma tumors. Here, we report on the ability of an anticancer nitrone compound, OKN-007 [Oklahoma Nitrone 007; a disulfonyl derivative of α-phenyl-tert-butyl nitrone (PBN)] to decrease free radical levels in F98 rat gliomas using combined molecular magnetic resonance imaging (mMRI) and immunospin-trapping (IST) methodologies. Free radicals are trapped with the spin-trapping agent, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), to form DMPO macromolecule radical adducts, and then further tagged by immunospin trapping by an antibody against DMPO adducts. In this study, we combined mMRI with a biotin-Gd-DTPA-albumin-based contrast agent for signal detection with the specificity of an antibody for DMPO nitrone adducts (anti-DMPO probe), to detect in vivo free radicals in OKN-007-treated rat F98 gliomas. OKN-007 was found to significantly decrease (P free radical levels detected with an anti-DMPO probe in treated animals compared to untreated rats. Immunoelectron microscopy was used with gold-labeled antibiotin to detect the anti-DMPO probe within the plasma membrane of F98 tumor cells from rats administered anti-DMPO in vivo. OKN-007 was also found to decrease nuclear factor erythroid 2-related factor 2, inducible nitric oxide synthase, 3-nitrotyrosine, and malondialdehyde in ex vivo F98 glioma tissues via immunohistochemistry, as well as decrease 3-nitrotyrosine and malondialdehyde adducts in vitro in F98 cells via ELISA. The results indicate that OKN-007 effectively decreases free radicals associated with glioma tumor growth. Furthermore, this method can potentially be applied toward other types of cancers for the in vivo detection of macromolecular free radicals and the assessment of antioxidants. Copyright © 2015. Published by Elsevier Inc.

Scavenging capacity of strawberry tree (Arbutus unedo L.) leaves on free radicals.

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Oliveira, Ivo; Coelho, Valentim; Baltasar, Raquel; Pereira, José Alberto; Baptista, Paula

2009-07-01

Despite strawberry tree (Arbutus unedo L.) leaves had a long use in traditional medicine due to its antiseptic, diuretic, astringent and depurative properties, the potential of their antioxidant activity are still lacking. Our study goals to assess the antioxidant and free radical scavenging potential of water, ethanol, methanol and diethyl ether extracts of A. unedo leaves. Total phenols content was achieved spectrophotometrically using Folin-Ciocalteau reagent with gallic acid as standard. Antioxidant activity was evaluated using three different methods: reducing power of iron (III)/ferricyanide complex assay, scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and scavenging effect on superoxide radicals by using the PMS-NADH-nitroblue tetrazolium system. Ethanol extracts of A. unedo leaves were the highest in reducing power (IC(50) 232.7 microg/mL) and DPPH scavenging effect (IC(50) 63.2 microg/mL) followed by water extracts (with IC(50) of 287.7 and 73.7 microg/mL, respectively); whereas diethyl ether extracts were the lowest. In the scavenging on superoxide radical assay, methanol extracts obtained the best results (IC(50) 6.9 microg/mL). For all the methods tested the antioxidant activity was concentration dependent. In accordance with antioxidant activity, highest total phenols content were found in ethanol, followed by water, methanol and diethyl ether extract. The results indicated that A. unedo leaves are a potential source of natural antioxidants.

Anthocyanin Characterization, Total Phenolic Quantification and Antioxidant Features of Some Chilean Edible Berry Extracts

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Anghel Brito

2014-07-01

Full Text Available The anthocyanin composition and HPLC fingerprints of six small berries endemic of the VIII region of Chile were investigated using high resolution mass analysis for the first time (HR-ToF-ESI-MS. The antioxidant features of the six endemic species were compared, including a variety of blueberries which is one of the most commercially significant berry crops in Chile. The anthocyanin fingerprints obtained for the fruits were compared and correlated with the antioxidant features measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP, the superoxide anion scavenging activity assay (SA, and total content of phenolics, flavonoids and anthocyanins measured by spectroscopic methods. Thirty one anthocyanins were identified, and the major ones were quantified by HPLC-DAD, mostly branched 3-O-glycosides of delphinidin, cyanidin, petunidin, peonidin and malvidin. Three phenolic acids (feruloylquinic acid, chlorogenic acid, and neochlorogenic acid and five flavonols (hyperoside, isoquercitrin, quercetin, rutin, myricetin and isorhamnetin were also identified. Calafate fruits showed the highest antioxidant activity (2.33 ± 0.21 μg/mL in the DPPH assay, followed by blueberry (3.32 ± 0.18 μg/mL, and arrayán (5.88 ± 0.21, respectively.

Effect of five year storage on total phenolic content and antioxidant capacity of almond (Amygdalus communisL.) hull and shell from different genotypes.

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Moosavi Dolatabadi, Khadijeh Sadat; Dehghan, Gholamreza; Hosseini, Siavash; Jahanban Esfahlan, Ali

2015-01-01

Almond (Prunus amygdalus) hull and shell are agricultural by-products that are a source of phenolic compounds.The processing of almond produce shell and hull, accounts for more than 50% by dry weight of the almond fruits. Recently, more studies have focused on the influence of storage conditions and postharvest handling on the nutritional quality of fruits, especially the antioxidant phenolics. In this study, influence of long-term storage (five years) on the total phenolic and antioxidant capacity of almond hull and shell from different genotypes was evaluated. The fruits of subjected genotypes were collected and their hull and shell were separated. They were dried and reduced to fine powder. This powder stored at room temperature for five years. The total phenolic content (TPC) and bioactivities (antioxidant potential: DPPH and ABTS radical scavenging and reducing power) of extracts were evaluated using spectrophotometric methods. It was found that TPC content and bioactivity levels in the stored almond hull and shell were different, compared to the hulls and shells which were evaluated in 2007. S1-4 genotype had the highest TPC and reducing power in its hull and shell.Low correlation coefficient was observed between phenolic content and the DPPH radical scavenging percentage in hull and shell extract. For the first time, results of this investigation showed that storage can influence the antioxidant and antiradical potential of almond hull and shell.

Anti-oxidation and scavenging effects of some extracts from Chinese medicines on free radicals

International Nuclear Information System (INIS)

Wang Chongdao; Qiang Yizhong; Lao Qinhua; Cui Fengmei; Shao Yuan; Sun Cunpu

1999-11-01

The inhibiting effects of Chinonin, Quercetin and Tannic Acid on the lipid oxidation induced by radiation exposure were investigated by means of a modified TBA spectrophotometry. The scavenging effects on free radicals caused by γ-irradiation exposure of the three active principles were observed by technique of ESR. The results showed that anti-oxidation effects of Chinonin and Quercetin were better than that of Tannic Acid, while the scavenging effects of the three active principles on free radicals were similar

Antioxidant capacity and oxygen radical diseases in the preterm newborn.

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Rogers, S; Witz, G; Anwar, M; Hiatt, M; Hegyi, T

2000-06-01

Bronchopulmonary dysplasia, intraventricular hemorrhage, necrotizing enterocolitis, and retinopathy of prematurity may be different manifestations of oxygen radical diseases of prematurity (ORDP). To test the hypothesis that the antioxidant capacity of cord blood serum will predict risk of ORDP. An inception cohort of premature neonates was followed up from birth until discharge or death to determine if outcome was related to cord blood serum antioxidant capacity, as determined by a manual assay measuring the relative inhibition of oxidation of 2,2'-azino-di-(3-ethylbenzthiazoline)-6 sulfonic acid (ABTS). Possible correlations between antioxidant capacity and various perinatal factors were also tested. Level 3 newborn intensive care unit. All inborn very low-birth-weight neonates from whom cord blood was available and for whom maternal consent was obtained were included. Newborns who died in the first week of life or who had major congenital malformations were excluded. A convenience sample of newborns weighing more than 1500 g was used to perfect assay and explore confounders. Significant ORDP was defined as the presence of intraventricular hemorrhage greater than grade 2, retinopathy of prematurity greater than stage 1, bronchopulmonary dysplasia at the postconceptional age of 36 weeks, or necrotizing enterocolitis with the hypothesis that neonates with ORDP will have lower antioxidant capacity in cord blood serum. Serum antioxidant capacity at birth correlated with gestational age for the entire sample of 41 neonates and for the 26 neonates born before 32 weeks' gestation. After correction for gestational age, cord serum antioxidant capacity did not correlate with maternal smoking, preeclampsia, chorioamnionitis, cord pH Apgar scores, or any of the ORDP studied. Cord serum antioxidant capacity correlates with gestational age but does not predict ORDP risk.

Cotinus coggyria: a rich source of antioxidants.

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Riaz, Tauheeda; Abbasi, Muhammad Athar; Aziz-ur-Rehman; Rubab, Kaniz; Shahzadi, Tayyaba; Ajaib, Muhammad; Khan, Khalid Mohammed

2012-07-01

Methanolic extract of Cotinus coggyria Scop. was mixed in distilled water and partitioned first with the n-hexane, then with chloroform, then ethyl acetate and at the end with n-butanol. The phytochemical screening of plant showed presence of the phenolics, cardiac glycosides and flavonoides in large amount in the chloroform, n-butanol and ethyl acetate soluble fraction. Antioxidant activity of these four fractions and the left behind aqueous fraction was measured by four methods such as: 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, ferric thiocyanate assay, ferric reducing antioxidant power (FRAP) assay and total antioxidant activity. Total phenolics were also measured. Noteworthy antioxidant potential was shown by the chloroform, n-butanol and ethyl acetate soluble fraction showed. Ethyl acetate fraction showed highest % inhibition of the DPPH radical when compared with the other studied fractions i.e. 81.64 ± 1.29% inhibition of the DPPH radical at the concentration of 30 μg/ml. Its IC(50) value was found to be 15.58 ± 0.09 μg/ml, comparative to the butylated hydroxytoluene (BHT), which has IC(50) value 12.6 ± 0.85μg/ml. This fraction also showed the highest lipid peroxidation inhibition (61.41 ± 1.16%), as well as highest values of FRAP (697.76 ± 1.98 μg of trolox equivalents) total antioxidant activity (1.02 ± 0.09) and total phenolic contents (229.34 ± 0.57) comparative to the other studied fractions. The chloroform and n-butanol soluble fraction also showed good results for all the studied antioxidant assays.

Dietary Protection Against Free Radicals: A Case for Multiple Testing to Establish Structure-activity Relationships for Antioxidant Potential of Anthocyanic Plant Species

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Chiara Cheng Lim

2009-03-01

Full Text Available DNA damage by reactive species is associated with susceptibility to chronic human degenerative disorders. Anthocyanins are naturally occurring antioxidants, that may prevent or reverse such damage. There is considerable interest in anthocyanic food plants as good dietary sources, with the potential for reducing susceptibility to chronic disease. While structure-activity relationships have provided guidelines on molecular structure in relation to free hydroxyl- radical scavenging, this may not cover the situation in food plants where the anthocyanins are part of a complex mixture, and may be part of complex structures, including anthocyanic vacuolar inclusions (AVIs. Additionally, new analytical methods have revealed new structures in previously-studied materials. We have compared the antioxidant activities of extracts from six anthocyanin-rich edible plants (red cabbage, red lettuce, blueberries, pansies, purple sweetpotato skin, purple sweetpotato flesh and Maori potato flesh using three chemical assays (DPPH, TRAP and ORAC, and the in vitro Comet assay. Extracts from the flowering plant, lisianthus, were used for comparison. The extracts showed differential effects in the chemical assays, suggesting that closely related structures have different affinities to scavenge different reactive species. Integration of anthocyanins to an AVI led to more sustained radical scavenging activity as compared with the free anthocyanin. All but the red lettuce extract could reduce endogenous DNA damage in HT-29 colon cancer cells. However, while extracts from purple sweetpotato skin and flesh, Maori potato and pansies, protected cells against subsequent challenge by hydrogen peroxide at 0oC, red cabbage extracts were pro-oxidant, while other extracts had no effect. When the peroxide challenge was at 37oC, all of the extracts appeared pro-oxidant. Maori potato extract, consistently the weakest antioxidant in all the chemical assays, was more effective in the

Antioxidant Potential of Selected Korean Edible Plant Extracts

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Yaejin Woo

2017-01-01

Full Text Available This study aimed to evaluate the antioxidant activity of various plant extracts. A total of 94 kinds of edible plant extracts obtained from the Korea Plant Extract Bank were screened for cytotoxicity, following which the total phenolic content of 24 shortlisted extracts was determined. Of these, extracts from three plants, namely, Castanea crenata (CC leaf, Camellia japonica (CJ fruit, and Viburnum dilatatum (VD leaf, were examined for antioxidant capabilities by measuring radical scavenging activity, ferric reducing/antioxidant power, and lipid peroxidation inhibitory activity. In addition, cellular antioxidant activities of the three extracts were assessed by a cell-based dichlorofluorescein assay and antioxidant response element (ARE reporter activity assay. The results demonstrated that all three extracts concentration-dependently scavenged free radicals, inhibited lipid peroxidation, reduced the cellular level of reactive oxygen species, and increased ARE-luciferase activity, indicating antioxidant enzyme-inducing potential. In particular, CJ extract showed significantly greater antioxidative activity and antimigratory effect in a breast cancer cell line compared to CC and VD extracts. Hence, CJ extract deserves further study for its in vivo functionality or biologically active constituents.

Free radical generation induced by ultrasound in red wine and model wine: An EPR spin-trapping study.

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Zhang, Qing-An; Shen, Yuan; Fan, Xue-Hui; Martín, Juan Francisco García; Wang, Xi; Song, Yun

2015-11-01

Direct evidence for the formation of 1-hydroxylethyl radicals by ultrasound in red wine and air-saturated model wine is presented in this paper. Free radicals are thought to be the key intermediates in the ultrasound processing of wine, but their nature has not been established yet. Electron paramagnetic resonance (EPR) spin trapping with 5,5-dimethyl-l-pyrrolin N-oxide (DMPO) was used for the detection of hydroxyl free radicals and 1-hydroxylethyl free radicals. Spin adducts of hydroxyl free radicals were detected in DMPO aqueous solution after sonication while 1-hydroxylethyl free radical adducts were observed in ultrasound-processed red wine and model wine. The latter radical arose from ethanol oxidation via the hydroxyl radical generated by ultrasound in water, thus providing the first direct evidence of the formation of 1-hydroxylethyl free radical in red wine exposed to ultrasound. Finally, the effects of ultrasound frequency, ultrasound power, temperature and ultrasound exposure time were assessed on the intensity of 1-hydroxylethyl radical spin adducts in model wine. Copyright © 2015 Elsevier B.V. All rights reserved.

Total antioxidant/oxidant status in meningism and meningitis.

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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 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.

Antioxidant activity of nine Fabaceae species growing in Serbia and Montenegro.

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Godevac, Dejan; Zdunić, Gordana; Savikin, Katarina; Vajs, Vlatka; Menković, Nebojsa

2008-04-01

The aim of this study was to investigate antioxidant capacity of nine Fabaceae species collected on the mountains of Serbia and Montenegro. Antioxidant assays with various reaction mechanisms were used, including total phenolic content by Folin-Ciocalteu, DPPH radical scavenging capacity, Trolox equivalent antioxidant capacity (TEAC) values by ABTS radical cation and inhibition of liposome peroxidation. The investigated plants exhibited strong antioxidant capacity in all the tested methods, and among them, Lathyrus binatus, Trifolium pannonicum, and Anthyllis aurea were found to be the most active.

Synthesis, antioxidant and antibacterial activities of 3-nitrophenyl ferrocene

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Benabdesselam, S.; Izza, H.; Lanez, T.; Guechi, E. K.

2018-03-01

The current work aims in its first part to synthesize 3-nitrophenylferrocene after diazotizing nitroaniline in the meta position by the sodium nitrite and the formation of the corresponding diazonium salt: 3-nitrobenzendiazonium sulfate, then the salt in solution was added to the ferrocene for the purpose of introducing the nitrophenyl moiety thereon (arylation) and the formation of 3-nitrophenylferrocene. The second part is devoted to the study of the antioxidant activity of 3-NPF by applying the trapping test of superoxide radical using cyclic voltammetry, the free radical DPPH trapping test by spectrophotometry. The results showed that 3-nitrophenylferrocene has a scavenging effect of DPPH radical with IC50 = 1.44mg/ml, superoxide radical with IC50=5.38mg/ml. The third part is devoted to the study of antibacterial activity of the synthesized compound tested on four strains of bacteria: Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis and Klebsiella pneumoniae. The obtained results clearly showed that 3-nitrophenylferrocene has low activities on the four bacterial strains with diameters of inhibition zones do not exceeding 17 mm at concentrations of 25mg/ml.

Reactions of nitroxide radicals in aqueous solutions exposed to non-thermal plasma: limitations of spin trapping of the plasma induced species

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Gorbanev, Yury; Stehling, Nicola; O'Connell, Deborah; Chechik, Victor

2016-10-01

Low temperature (‘cold’) atmospheric pressure plasmas have gained much attention in recent years due to their biomedical effects achieved through the interactions of plasma-induced species with the biological substrate. Monitoring of the radical species in an aqueous biological milieu is usually performed via electron paramagnetic resonance (EPR) spectroscopy using various nitrone spin traps, which form persistent radical adducts with the short-lived radicals. However, the stability of these nitroxide radical adducts in the plasma-specific environment is not well known. In this work, chemical transformations of nitroxide radicals in aqueous solutions using a model nitroxide 4-oxo-TEMPO were studied using EPR and LC-MS. The kinetics of the nitroxide decay when the solution was exposed to plasma were assessed, and the reactive pathways proposed. The use of different scavengers enabled identification of the types of reactive species which cause the decay, indicating the predominant nitroxide group reduction in oxygen-free plasmas. The 2H adduct of the PBN spin trap (PBN-D) was shown to decay similarly to the model molecule 4-oxo-TEMPO. The decay of the spin adducts in plasma-treated solutions must be considered to avoid rendering the spin trapping results unreliable. In particular, the selectivity of the decay indicated the limitations of the PTIO/PTI nitroxide system in the detection of nitric oxide.

Comparison of different tests used in mapping the Greek virgin olive oil production for the determination of its total antioxidant capacity

Energy Technology Data Exchange (ETDEWEB)

Minioti, K. S.; Georgiou, C. A.

2010-07-01

This study aims to map the total antioxidant capacity (Tac) of 50 Greek olive oil samples from the 2005-2006 season according to production region and cultivar and to compare the 2, 2'-amino-bis (3-ethylbenzo-thiazoline-6- sulfonic acid (Abets), 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH) and F olin-Ciocalteu tests for use with olive oil. Antioxidant capacities determined in the hydrophilic fraction range between 5.42 - 22.5 mM gallic acid Kg{sup -}1 olive oil for the ABTS method and 1.29 - 9.95 mM Kg{sup -}1 for the DPPH method while in total, olive oil TAC ranges between 77 - 177 mM Kg{sup -}1 as assessed by the DPPH method. The results of total phenol content range between 3.8 and 29.4 mM Kg{sup -}1 olive oil. Total phenol content correlates with total antioxidant capacity assessed in the hydrophilic fraction through the DPPH (r = 0.89) and the ABTS (r = 0.69) assays. The hydrophilic fraction DPPH values correlate significantly with the ABTS values (r = 0.81). However, the DPPH values for total olive oil correlate poorly with the ABTS assay, the Folin-Ciocalteu method and the DPPH assay in hydrophilic fraction. Although total phenolic content shows good correlation with ABTS and DPPH values and could serve as a useful indicator for olive oil antioxidant capacity, the use of a battery of tests contributes to better characterization of the antioxidant capacity of olive oil. (Author) 14 refs.

Evidence for formation of hydroxyl radicals during reperfusion after global cerebral ischaemia in rats using salicylate trapping and microdialysis

DEFF Research Database (Denmark)

Christensen, Thomas; Bruhn, T; Balchen, T

1994-01-01

Systemic administration of salicylate (SA) to rats (100 mg kg-1 i.p. ) was used as an in vivo trap of hydroxyl radicals (.OH). In the brain SA reacts with hydroxyl radicals to form the stable adducts 2, 3- and 2,5 dihydroxybenzoic acid (DHBAs) which can thus be taken as an index of .OH formation...

Determination of total phenolic content and antioxidant activitity of methanol extract of Maranta arundinacea L fresh leaf and tuber

Science.gov (United States)

Kusbandari, A.; Susanti, H.

2017-11-01

Maranta arundinacea L is one of herbaceous plants in Indonesia which have flavonoid content. Flavonoids has antioxidants activity by inhibition of free radical oxidation reactions. The study aims were to determination total phenolic content and antioxidant activity of methanol extract of fresh leaf and tuber of M. arundinacea L by UV-Vis spectrophotometer. The methanol extracts were obtained with maceration and remaseration method of fresh leaves and tubers. The total phenolic content was assayed with visible spectrophotometric using Folin Ciocalteau reagent. The antioxidant activity was assayed with 1,1-diphenyl-2-picrilhidrazil (DPPH) compared to gallic acid. The results showed that methanol extract of tuber and fresh leaf of M. arundinacea L contained phenolic compound with total phenolic content (TPC) in fresh tuber of 3.881±0.064 (% GAE) and fresh leaf is 6.518±0.163 (% b/b GAE). IC50 value from fresh tuber is 1.780±0.0005 μg/mL and IC50 fresh leaf values of 0.274±0.0004 μg/mL while the standard gallic acid is IC50 of 0.640±0.0002 μg/mL.

Aloe vera extract reduces 8-oxo-2'-deoxyguanosine levels and improves total antioxidants in streptozotocin-induced diabetic rats

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Wulan Christijanti

2017-04-01

Full Text Available Background Diabetes mellitus is a chronic disease caused by lack of insulin production in the pancreas or by insulin resistance, the disease being characterized by elevated blood glucose levels. Hyperglycemia in diabetes could lead to oxidative stress due to the rise in 8-oxo-2'-deoxyguanosine (8-oxo-dG levels and the decrease in levels of total antioxidant status (TAS. The purpose of this study was to assess the effect Aloe vera extract on 8-oxo-dG level and total antioxidant status in diabetic rat testis.   Methods This was an experimental laboratory study with 20 rat samples which were divided into 4 groups (1 control group and 3 treatment groups. Diabetes was induced in the rats by streptozotocin (STZ at 65 mg/kgBW. The diabetic rats were then treated for 28 days with Aloe vera extract at 0 mg (P0, 200 mg rind (P1, 200 mg pulp (P2, respectively. The level of 8 -oxo-dG was measured by ELISA and total antioxidant status with 2,2' -azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS. Data were analyzed with ANOVA and Least Significant Difference Advanced Test at P<0.05.   Results 8-Oxo-dG levels were significantly different between the control group and both P0 and P2, but not between the control group and P1. Among the treatment groups the 8-oxo-dG levels were significantly different. Mean total antioxidant status was significantly different between control and treatment groups, and also between treatment groups (p<0.05.   Conclusions Aloe vera extract reduced free radicals (level of 8-oxo-dG and increased the total antioxidant status in diabetic rat testis.

Determination of total antioxidant capacity by a new spectrophotometric method based on Ce(IV) reducing capacity measurement.

Science.gov (United States)

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

EVALUATION OF FREEZE DRIED ALOE VERA AND NOPAL CACTUS FOR POSSIBLE HEALTH TREATMENTS BY COMPARISON OF ANTIOXIDANT PROPERTIES AND FREE RADICAL INHIBITION.

Science.gov (United States)

Rodriguez, Kenneth R; Jones, Anthony E; Belmont, Barbara

2014-01-01

The goal of this project was to characterize the antioxidant powers of lyophilized Aloe Vera ( Aloe barbadensis ) and Nopal Cactus (Opuntia ficus-indica) by quantifying the phenolics content and radical scavenging abilities of preparations derived from these plants. Extracts of these lyophylized succulents were assayed for phenolic compounds by the Folin Ciocalteau method and compared for free radical scavenging capability by the DPPH method. We found that even though the Aloe lyophilizate extract contained more phenolic content, the Nopal lyophilizate exhibited better free radical scavenging ability. Aloe Vera extract contained 0.278 g/L of phenolic content and exhibited 11.1% free radical inhibition, with a free radical scavenging rate constant of 0.177±0.015 min -1 . Nopal Cactus extract contained 0.174 g/L of phenolic content and exhibited 13.2% free radical inhibition, with a free radical scavenging rate constant of 0.155±0.009 min -1 . These results showed Nopal to have greater antioxidant potency than Aloe.

Changes in the amino acid profiles and free radical scavenging activities of Tenebrio molitor larvae following enzymatic hydrolysis.

Science.gov (United States)

Tang, Yujiao; Debnath, Trishna; Choi, Eun-Ju; Kim, Young Wook; Ryu, Jung Pyo; Jang, Sejin; Chung, Sang Uk; Choi, Young-Jin; Kim, Eun-Kyung

2018-01-01

Tenebrio molitor (T. molitor) larvae provide food at low environmental cost and contribute positively to livelihoods. In this research, we compared the amino acids compositions and antioxidant activities of various extracts of T. molitor to enhance their quality as food. For the comparison, distilled water extracts, enzymatic hydrolysates, and condensed enzymatic hydrolysates of T. molitor larvae were prepared. Their amino acids (AAs) profiles and antioxidant activities, including ferric-reducing antioxidant power, oxygen radical absorption capacity, and DPPH, hydroxyl radical, and hydrogen peroxide radical scavenging properties assay were analyzed. DW extracts had the lowest AAs contents and antioxidant activity compared with enzymatic extracts. Condensed hydrolysates with a combination of alcalase and flavourzyme (C-A+F) exhibited the highest levels of total free AAs (11.1759 g/100 g). C-A+F produced higher total hydrolyzed AAs (32.5292 g/100 g) compared with the other groups. The C-A+F possessed the strongest antioxidant activity. Notably, the antioxidant activities of the hydrolysates and the total hydrolyzed AAs amount were correlated. Taken together, our findings showed that C-A+F was a promising technique for obtaining extracts of T. molitor larvae with antioxidant activity as potential nutritious functional food.

Determination of the free radical concentration ratio in the copolymerization of methyl acrylate and styrene. Application of radical trapping and 15N NMR spectroscopy

NARCIS (Netherlands)

Kelemen, P.; Klumperman, B.

2004-01-01

15N-labeled nitroxides are employed to trap propagating radicals in the copolymn. of styrene and Me acrylate. The resulting polymeric alkoxyamines are analyzed by 15N NMR.The assignment of the obsd. bands to the two possible end groups of the propagating copolymer chain is achieved by comparison of

Effect of five year storage on total phenolic content and antioxidant capacity of almond (Amygdalus communisL. hull and shell from different genotypes

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Khadijeh Sadat Moosavi Dolatabadi

2014-12-01

Full Text Available Objectives: Almond (Prunus amygdalus hull and shell are agricultural by-products that are a source of phenolic compounds.The processing of almond produce shell and hull, accounts for more than 50% by dry weight of the almond fruits. Recently, more studies have focused on the influence of storage conditions and postharvest handling on the nutritional quality of fruits, especially the antioxidant phenolics. In this study, influence of long-term storage (five years on the total phenolic and antioxidant capacity of almond hull and shell from different genotypes was evaluated. Materials and Methods: The fruits of subjected genotypes were collected and their hull and shell were separated. They were dried and reduced to fine powder. This powder stored at room temperature for five years. The total phenolic content (TPC and bioactivities (antioxidant potential: DPPH and ABTS radical scavenging and reducing power of extracts were evaluated using spectrophotometric methods. Results: It was found that TPC content and bioactivity levels in the stored almond hull and shell were different, compared to the hulls and shells which were evaluated in 2007. S1-4 genotype had the highest TPC and reducing power in its hull and shell.Low correlation coefficient was observed between phenolic content and the DPPH radical scavenging percentage in hull and shell extract. Conclusions: For the first time, results of this investigation showed that storage can influence the antioxidant and antiradical potential of almond hull and shell.

Herbal antioxidant in clinical practice: A review

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Shashi Alok

2014-01-01

Full Text Available Antioxidant-the word itself is magic. Using the antioxidant concept as a spearhead in proposed mechanisms for staving off so-called “free-radical” reactions, the rush is on to mine claims for the latest and most effective combination of free-radical scavenging compounds. We must acknowledge that such “radicals” have definitively been shown to damage all biochemical components such as DNA/RNA, carbohydrates, unsaturated lipids, proteins, and micronutrients such as carotenoids (alpha and beta carotene, lycopene, vitamins A, B6, B12, and folate. Defense strategies against such aggressive radical species include enzymes, antioxidants that occur naturally in the body (glutathione, uric acid, ubiquinol-10, and others and radical scavenging nutrients, such as vitamins A, C, and E, and carotenoids. This paper will present a brief discussion of some well- and little-known herbs that may add to the optimization of antioxidant status and therefore offer added preventive values for overall health. It is important to state at the outset that antioxidants vary widely in their free-radical quenching effects and each may be individually attracted to specific cell sites. Further evidence of the specialized nature of the carotenoids is demonstrated by the appearance of two carotenoids in the macula region of the retina where beta-carotene is totally absent.

Changes in antioxidant activity, total phenolic and abscisic acid constituents in the aquatic plants Myriophyllum spicatum L. and Myriophyllum triphyllum Orchard exposed to cadmium.

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Sivaci, Aysel; Sivaci, E Ridvan; Sökmen, Münevver

2007-07-01

Changes in antioxidant activity, total phenolic and abscisic acid (ABA) constituents of Myriophyllum spicatum L. and Myriophyllum triphyllum Orchard, cadmium (Cd) aqueous macrophytes, were investigated exposed to 0, 2, 4, 6, 8, 16 mg l(-1) Cd concentrations. M. triphyllum exhibited strong antioxidant activity but not M. spicatum before and after exposure. Free radical scavenging activity of M. triphyllum was significantly affected from the Cd concentrations and a significant increase was observed at 6 mgl(-1) Cd concentration. Total phenolic constituent and ABA concentration of M. triphyllum is higher than that of M. spicatum with or without heavy metal exposure (P macrophytes that grown in polluted aqueous ecosystem.

Extraction of total polyphenols from hibiscus (Hibiscus sabdariffa L. and waxweed / ‘sete-sangrias’ (Cuphea carthagenensis and evaluation of their antioxidant potential

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Daniele Begmeier

2014-02-01

Full Text Available Current research investigates the extraction process of total polyphenols from hibiscus (Hibiscus sabdariffa L. and waxweed (Brazilian name: ‘sete-sangrias’ (Cuphea carthagenensis and evaluates the antioxidant potential of their extracts. The extraction stage comprised investigation on the following parameters: i solvents (acetone and ethanol pure and fractioned with water; ii variables (temperature, stirring, solvent ratio, time and pH. Total polyphenols were quantified by Folin-Ciocalteau reagent and antioxidant activity was determined by ABTS•+ (2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid and DPPH (2,2-diphenyl-1-picrylhydrazyl radical scavenging assay. Results showed that, depending on experimental conditions, total phenolic contents for hibiscus and waxweed ranged between 460.86 mg GAE 100 g-1 and 5012.54 mg GAE 100 g-1 and between 462.86 mg GAE 100 g-1 and 4215.99 mg GAE 100 g-1, respectively. Waxweed had a higher antioxidant activity when compared to that of hibiscus by both ABTS•+ and DPPH. Data showed that hibiscus and waxweed have a significant amount of polyphenols which may be extracted in mild processing conditions and then employed as natural antioxidant sources in industrial processes.

Total phenolic content and antioxidant activities of pomegranate juice and whey based novel beverage fermented by kefir grains.

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Sabokbar, Nayereh; Khodaiyan, Faramarz

2016-01-01

Mixture of pomegranate juice and whey was evaluated as a potential substrate for production of a novel beverage by kefir grains. The effects of two different variables, fermentation, temperature (19 and 25 °C) and kefir grain amount (5 %w/v and 8 %w/v), on total phenolic content (TPC) and antioxidant activities of beverage were examined during a fermentation time of 32 h. TPC and antioxidant activities including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, reducing power, inhibition effect upon linoleic acid autoxidation and inhibition effect upon ascorbate autoxidation increased significantly (p < 0.05) during fermentation, but metal chelating effect showed no significant difference. The highest increases were observed when the temperature of 25 °C and kefir grain amount of 8 %w/v were applied. Results proved antioxidant activities of beverages were desirable and fermentation by kefir grains has the ability to enhance these antioxidant activities, as compared with unfermented beverage. Also pomegranate juice and whey were suitable media for producing a novel dairy-juice beverage.

Variations in antioxidant content in leaves and fruits of Ficus fistulosa

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Hlail, Shrrog Hammed; Wan Ahmad, Wan Juliana; Abdullah, Aminah

2014-09-01

This study evaluated the effects of (rural vs urban) forest conditions on the total phenolic content and antioxidants activity of Ficus fistulosa in four locations (Bangi, Ayer Hitam, Chini and Bera Forest Reserves) in Malaysia. Total phenolic content of Ficus leaves and fruits extracts was determined by the Foline-Ciocalteau method and the antioxidant activity of Ficus leaves and fruits was measured by ferric reducing antioxidant power (FRAP), 2, 2-Dipheny-1-picryhydrazyl radical (DPPH) scavenging activity and oxygen radical absorbance capacity (ORAC). The TPC and antioxidant activity of F.fistulosa leaves and fruits extracts were significantly (Pextracts ranged from251.74 to 321.75 mg /100g DW, 75.49 to 90.54%, and 158.36 to 114.18μmol TE/100g DW respectively. The results suggested that F. fistulosa leaves and fruits are a goodsources of natural antioxidants.

A study on the comparison of antioxidant effects among cultivated ginseng, and cultivated wild ginseng extracts -Using the measurement of superoxide and hydroxy radical scavenging activities-

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Tae Jin, Rhim

2009-06-01

Full Text Available Objectives : The objective of this study was to compare the antioxidant effects among cultivated wild ginseng and ginseng extracts. Methods : In vitro antioxidant activities were examined by superoxide and hydroxyl radical scavenging activities of ginseng and cultivated wild ginseng extracts. Results : 1. In the superoxide radical scavenging activities of ginseng and cultivated wild ginseng extracts, antioxidant activities of cultivated wild ginseng extracts was showed higher than cultivated ginseng in the concentration of 0.25 and 0.50㎎/㎖. 2. In the hydroxyl radical scavenging activities of ginseng and cultivated wild ginseng extracts, antioxidant activities of cultivated wild ginseng extracts was showed higher than cultivated ginseng in the concentration of 1.0, 2.5, and 5.0㎎/㎖. Conclusions : In summary, the results of this study demonstrate that cultivated wild ginseng extracts had higher antioxidant activities to cultivated ginseng.

Chemical Composition, In Vitro Antimicrobial, Free-Radical-Scavenging and Antioxidant Activities of the Essential Oil of Leucas inflata Benth

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Ramzi A. Mothana

2017-02-01

Full Text Available The essential oil of Leucas inflata Balf.f. (Lamiaceae, collected in Yemen, was analyzed using gas chromatography (GC and gas chromatography-mass spectrometry (GC-MS techniques. Forty-three components were recognized, representing 89.2% of the total oil. The L. inflata volatile oil was found to contain a high percentage of aliphatic acids (51.1%. Hexadecanoic acid (32.8% and n-dodecanoic acid (7.8% were identified as the major compounds. Oxygenated monoterpenes were distinguished as the second significant group of constituents (16.0%. Camphor (6.1% and linalool (3.2% were found to be the main components among the oxygenated monoterpenes. In addition, the volatile oil was assessed for its antimicrobial activity against four bacterial strains and one yeast species using broth micro-dilution assay for minimum inhibitory concentrations (MIC. In addition, antioxidant activity was measured utilizing the anti-radical activity of the sable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH and β-Carotene-linoleic acid assays. The oil of L. inflata showed an excellent antibacterial activity against only the tested Gram-positive bacteria with a MIC-value of 0.81 mg/mL. Furthermore, the oil demonstrated, at a concentration of 1 mg/mL, a weak to moderate antiradical and antioxidant activity of 38% and 32%, respectively.

Effect of Sulfites on Antioxidant Activity, Total Polyphenols, and Flavonoid Measurements in White Wine.

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Nardini, Mirella; Garaguso, Ivana

2018-03-09

Polyphenols content and antioxidant activity are directly related to the quality of wine. Wine also contains sulfites, which are added during the winemaking process. The present study aimed to evaluate the effects of sulfites on the assays commonly used to measure the antioxidant activity and polyphenols and flavonoids content of white wines. The effects of sulfites were explored both in the standard assays and in white wine. The addition of sulfites (at 1-10 μg) in the standard assays resulted in a significant, positive interference in the Folin-Ciocalteu's assay used for polyphenols measurements and in both the Ferric Reducing Antioxidant Power and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation decolorization assays, which were used for antioxidant activity evaluation. A negative interference of sulfites (at 1-20 μg) was observed for the colorimetric aluminium-chloride flavonoids assay. The addition of sulfites to organic white wines (at 25-200 mg/L wine) clearly resulted in a significant overestimation of antioxidant activity and polyphenols content, and in an underestimation of flavonoids concentration. To overcome sulfite interferences, white wines were treated with cross-linked polyvinylpyrrolidone. The total polyphenols content and antioxidant activity measurements obtained after polyvinylpyrrolidone treatment were significantly lower than those obtained in the untreated wines. Flavonoids were expected to be higher after polyvinylpyrrolidone treatment, but were instead found to be lower than for untreated wines, suggesting that in addition to sulfites, other non-phenolic reducing compounds were present in white wine and interfered with the flavonoid assay. In view of our results, we advise that a purification procedure should be applied in order to evaluate the quality of white wine.

Prophylactic antioxidants and phenolics of seagrass and seaweed ...

African Journals Online (AJOL)

Arun Kumar Agnihotri

KEY WORDS: Antioxidant; Total Phenols; Total Flavonoids; FRAP; TEAC; Seagrass;. Seaweed; Seasonal ... ozone (O3) and peroxynitrite (ONOO−) are not free radicals but can ... oxygen during respiration and from the synthesis of complex ...

Antioxidant and hepatoprotective activity of Cordia macleodii leaves

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Qureshi, Naseem N.; Kuchekar, Bhanudansh S.; Logade, Nadeem A.; Haleem, Majid A.

2009-01-01

This investigation was undertaken to evaluate ethanolic extract of Cordia macleodii leaves for possible antioxidant and hepatoprotective potential. Antioxidant activity of the extracts was evaluated by four established, in vitro methods viz. 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging method, nitric oxide (NO) radical scavenging method, iron chelation method and reducing power method. The extract demonstrated a significant dose dependent antioxidant activity comparable with ascorbic acid. The extract was also evaluated for hepatoprotective activity by carbon tetrachloride (CCl4) induced liver damage model in rats. CCl4 produced a significant increase in levels of serum glutamate pyruvate transaminase (GPT), serum glutamate oxaloacetate transaminase (GOT), Alkaline Phosphatase (ALP) and total bilirubin. Pretreatment of the rats with ethanolic extract of C. macleodii (100, 200 and 400 mg/kg po) inhibited the increase in levels of GPT, GOT, ALP and total bilirubin and the inhibition was comparable with Silymarin (100 mg/kg po). The present study revealed that C. macleodii leaves have significant radical scavenging and hepatoprotective activities. PMID:23960714

Serum total antioxidant capacity in patients with multiple sclerosis

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Almira Hadžović-Džuvo

2011-02-01

Full Text Available Multiple sclerosis (MS is a chronic inflammatory disease of the central nervous system (CNS. It is characterized by loss of myelin, the fatty tissue that surrounds and protects nerve fibres allowing them to conduct electrical impulses. Recent data indicate that oxidative stress (OS plays a major role in the pathogenesis of multiple sclerosis (MS. The aim of this study was to estimate level of serum total antioxidative capacity in patients with multiple sclerosis. Our cross-sectional study included 33 patients with MS and 24 age and sex matched control subjects. All our patients had a Poser criteria for definite diagnostic categories of multiple sclerosis. Serum total antioxidant capacity (TAC was measured by quantitative colorimetric determination, using Total antioxidant Capacity-QuantiCromAntioxidant Assay Kit (BioAssay systems, USA; DTAC-100. Mean serum TAC in multiple sclerosis group of patients was 119.2 mM Trolox equivalents and was significantly lower (p<0.001 compared to the control group of subjects (167.1 mM Trolox equivalents. Our results showed that oxidative stress plays an important role in pathogenesis of multiple sclerosis. This finding, also, suggests the importance of antioxidants in diet and therapy of MS patients.

Total oxidant/antioxidant status in jaundiced newborns before and after phototherapy.

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Aycicek, Ali; Erel, Ozcan

2007-01-01

To assess the effect of phototherapy on serum oxidant and antioxidant status in hyperbilirubinemic full-term newborns. Thirty-four full-term infants from 3 to 10 days of age exposed to phototherapy were studied. The serum antioxidant status was assessed by measuring the total antioxidant capacity (TAC) and individual antioxidant components: vitamin C, uric acid, albumin, thiol contents and total bilirubin. The oxidant status was assessed by determining the total oxidant status (TOS), oxidative stress index (OSI) and individual oxidant components: malondialdehyde (MDA), and lipid hydroperoxide levels. Vitamin C, uric acid, total bilirubin and MDA concentration were significantly lower, whereas serum TOS, lipid hydroperoxide and OSI levels were significantly higher after phototherapy (p total bilirubin and MDA (r = 0.434, p = 0.001). Although the MDA level was reduced after phototherapy, phototherapy has a negative impact on numerous parts of the oxidant/antioxidant defense system in jaundiced full-term newborns, exposing them to potential oxidative stress.

Antioxidant and free radical scavenging activities of Gastrodia elata Bl. and Uncaria rhynchophylla (Miq.) Jacks.

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Liu, J; Mori, A

1992-12-01

Gastrodia elata Bl. (GE) and Uncaria rhynchophylla (Miq.) Jacks (UR) are two traditional Chinese medicinal herbal drugs, used for the treatment of convulsions and epilepsy. Their antioxidant effects in vivo and their free radical scavenging effects in vitro were investigated. Epileptogenic foci in the lateral brain of the rat were induced by the injection of ferric chloride into the lateral cortex. Both extracts significantly inhibited the increase in levels of lipid peroxide in the ipsilateral cortex, at all times observed. In addition, the two extracts also induced an early increase of activity of superoxide dismutase in the mitochondrial fraction of the ipsilateral cortex. In in vitro experiments, the two extracts exhibited significant dose-dependent scavenging effects on free radicals, using electron spin resonance spectroscopy. These results suggest that the proposed antiepileptic effects of GE and UR may be attributable to the antioxidant activity of the active components in these two medicinal herbs.

Identifying the distinct features of geometric structures for hole trapping to generate radicals on rutile TiO₂(110) in photooxidation using density functional theory calculations with hybrid functional.

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Wang, Dong; Wang, Haifeng; Hu, P

2015-01-21

Using density functional theory calculations with HSE 06 functional, we obtained the structures of spin-polarized radicals on rutile TiO2(110), which is crucial to understand the photooxidation at the atomic level, and further calculate the thermodynamic stabilities of these radicals. By analyzing the results, we identify the structural features for hole trapping in the system, and reveal the mutual effects among the geometric structures, the energy levels of trapped hole states and their hole trapping capacities. Furthermore, the results from HSE 06 functional are compared to those from DFT + U and the stability trend of radicals against the number of slabs is tested. The effect of trapped holes on two important steps of the oxygen evolution reaction, i.e. water dissociation and the oxygen removal, is investigated and discussed.

Comparison of total polyphenols content and antioxidant potential of wines from ‘Welschriesling’ and ‘Sauvignon Blanc’ varieties during ageing on fine lees

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Jasna Lužar

2016-10-01

Full Text Available Phenolic compounds are key components of wine, since they contribute to wine characteristics such as colour, astringency and bitterness. They also act like antioxidants, with mechanisms involving free-radical scavenging that could prevent cardiovascular diseases and cancer. The aim of the present work was to compare the obtained results of total polyphenols content and antioxidant potential (AOP of several white wines (welschriesling and sauvignon blanc during ageing on fine lees. The total polyphenols content decreased in average for 16.1 % in welschriesling wines and for 18.7 % in sauvignon blanc wines in the period of three months of wine ageing on lees. In the same period AOP of wines decreased in average for 16.0 % in welschriesling wines and for 8.0 % in sauvignon blanc wines. Expectedly, the samples with added oak chips in grape must had higher antioxidant potential than others.

Antioxidant and antiglycation properties of two mango (Mangifera indica L. cultivars from Senegal

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Samba Fama Ndoye

2018-01-01

Full Text Available Objective: To evaluate the total phenolic contents, antioxidant and antiglycation activities of leaves, barks, roots and kernels from two cultivars of Mangifera indica (Anacardiaceae. Methods: Total phenolic contents were determined by using Folin-Ciocalteu's method. The antioxidant activities were assessed by three different protocols including DPPH, oxygen radical absorbance capacity and iron (II chelation assays. In addition, in vitro bovine serum albumin/D-ribose assay was chosen to evaluate the antiglycation properties of the extracts. Results: All the investigated extracts were found to contain high level of total phenols as well as potent antioxidant activities. Kernel extracts showed the highest total phenol contents and DPPH radical scavenging activities whereas higher oxygen radical absorbance capacity values were observed for leave, root and bark extracts. Besides, extracts from leaves, roots and barks from both cultivars exhibited potent inhibitory effects against the formation of advanced glycation end products, with IC50 values lower than the standard positive control aminoguanidine. Conclusions: The potent antiglycation and antioxidative activities of these two Mangifera indica cultivars suggest a possible role in targeting aging, diabetic complications and oxidative stress related diseases.

Evaluation of the Antioxidant Activity of Cell Extracts from Microalgae

OpenAIRE

F. Xavier Malcata; Pedro Moradas-Ferreira; Paula Tamagnini; A. C. Silva Ferreira; Maria S. Gião; Rui Seabra; A. Catarina Guedes

2013-01-01

A growing market for novel antioxidants obtained from non-expensive sources justifies educated screening of microalgae for their potential antioxidant features. Characterization of the antioxidant profile of 18 species of cyanobacteria (prokaryotic microalgae) and 23 species of (eukaryotic) microalgae is accordingly reported in this paper. The total antioxidant capacity, accounted for by both water- and lipid-soluble antioxidants, was evaluated by the (radical cation) ABTS method. For complem...

Antioxidant potential of Viscum articulatum burm

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Kannoth Mukundan Geetha

2013-01-01

Full Text Available Background: Free radical stress leads to tissue injury and progression of disease conditions such as arthritis, hemorrhagic shock, atherosclerosis, diabetes, hepatic injury, aging and ischemia, reperfusion injury of many tissues, gastritis, tumor promotion, neurodegenerative diseases, and carcinogenesis. Safer antioxidants suitable for long term use are needed to prevent or stop the progression of free radical mediated disorders. Viscum articulatum is traditionally used for various oxidative stress induced disorders including liver disorders. Aims: The present study investigated antioxidant activities of the methanolic extract of Viscum articulatum in in vivo and in vitro models to provide scientific basis for the traditional usage of this plant. Materials and Methods: The in vitro antioxidant activity was evaluated by determining the ability of the extract to scavenge 2, 2-diphenyl-2-picrylhydrazyl (DPPH, nitric oxide, 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid diammonium salt (ABTS, and hydrogen peroxide (H 2 O 2 which were assessed using spectroscopic methods. Results: The extract showed promising dose dependant free radical scavenging property in all the methods used. The extract effectively increased the superoxide dismutase and catalase activity and decreased lipid peroxidation in the treated groups indicating in vivo antioxidant activity. The extract also effectively decreased the serum levels of SGOT, SGPT, SALP, and total protein levels compared to toxicant control rats. Conclusion: The results obtained from this study indicate that Viscum articulatum is a potential source of antioxidant which would help in preventing many free radical mediated diseases.

Antioxidant activity of the new thiosulfinate derivative, S-benzyl phenylmethanethiosulfinate, from Petiveria alliacea L.

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Okada, Youji; Tanaka, Kaoru; Sato, Eisuke; Okajima, Haruo

2008-03-21

The antioxidant effects of the new thiosulfinate derivative, S-benzyl phenylmethanethiosulfinate (BPT), against the oxidation of cumene and methyl linoleate (ML) in chlorobenzene were studied in detail using HPLC. The results showed that BPT provided effective inhibition with a well-defined induction period under these oxidation conditions, and it was found that the stoichiometric factor (n), the number of peroxyl radicals trapped by one antioxidant molecule, of BPT is about 2. We then undertook a thorough investigation aimed at elucidating the active structural site of BPT. Various model compounds, such as diphenyl disulfide, dibenzyl disulfide, S-phenyl benzenethiosulfinate and S-ethyl phenylmethanethiosulfinate, were used which provided evidence that the benzylic hydrogen of BPT is mainly associated with the peroxyl radical scavenging. Moreover, we measured the rate constant for the reaction of BPT with peroxyl radicals derived from cumene and ML in chlorobenzene, and based on these measurements, BPT reacts with these peroxyl radicals with a rate constant of k(inh) = 8.6 x 10(3) and 6.2 x 10(4) M(-1) s(-1), respectively.

Radical-Scavenging Activity of Dietary Phytophenols in Combination with co-Antioxidants Using the Induction Period Method

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Seiichiro Fujisawa

2011-12-01

Full Text Available The radical-scavenging activity of dietary phytophenols has been investigated by many researches due to their antioxidant, anti-inflammatory and anticancer property but the radical-scavenging effect of 2-phytophenol and the phytophenol:co-antioxidants, vitamin C and thiol combination under nearly anaerobic conditions still remains unknown. The radical-scavenging activity for seventeen phytophenols and for six synthetic phenols (positive controls was investigated using the induction period method in the polymerization of methyl methacrylates (MMA initiated by thermal decomposition of benzoyl peroxide (BPO by monitoring differential scanning calorimetery (DSC. The kinh for the phytophenols was likely with the range 0.5 × 103 M−1s−1−2.2 × 103 M−1s−1, whereas that for synthetic phenols, hydroquinone and galvinoxyl, was with the range 7 × 103 M−1s−1−8 × 103 M−1s−1. Also, the additive scavenging effect of the (−-epigallocatechin (EGC:(−-epicatechin (EC and the (+-catechin:epicatechin (EC combination was observed at 1:1 molar ratio, whereas that of the EC:quercetin combination showed the cancel (prooxidative effect. Furthermore, the EGC:ASDB (L-ascorbyl 2,6-dibutylate or 2-ME (2-mercaptoethanol combination showed the prooxidative effect. Such enhancement of prooxidation in the combination may increase their toxic effects due to their cooxidation. Also, the synergic, additive or cancel effects of the flavonoid:vitamins E combination on the induction period in the BPO (a PhCOO* radical and 2,2′-azobisisobutyronitrile (AIBN, an R* radical systems are discussed.

Radiolysis study of the radical-like action mechanisms of an antioxidant: Sulfarlem

International Nuclear Information System (INIS)

Ruimy-Ifrah, Pascale

1989-01-01

Sulfarlem or p-anisyldithiolthione (ADT) is a sulfured heterocyclic compound which exhibits antioxidant properties. This work presents the quantitative study of the mono-electronic exchange mechanisms involved in this action. This study has been performed by gamma radiolysis and pulse radiolysis. The gamma radiolysis of ADT aerated ethanolic solutions has shown that O 2 . and RO 2 . radicals are not reactive towards ADT. In return, ADT is an efficient scavenger of R . radicals; the rate constant of this reaction being k (ADT + R . ) = 6.7 x 10 4 mol -1 .l.s -1 . The pulse radiolysis experiments allowed the characterization of ADT reduction by the solvated electron (k (e solv - + ADT) = 2.3 x 10 10 mol -1 .l.s -1 ), the determination of the absorption spectrum of the reduced species A . (maximum wavelength = 580 nm) and the rate constant of its evolution (k (A . + A . ) = 5.7 x 10 8 mol -1 .l.s -1 ). An analogous study has been performed with ADO, an ADT oxidized derivative, which appeared to be a less efficient free radicals scavenger. (author) [fr

Measuring sunscreen protection against solar-simulated radiation-induced structural radical damage to skin using ESR/spin trapping: development of an ex vivo test method.

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Haywood, Rachel; Volkov, Arsen; Andrady, Carima; Sayer, Robert

2012-03-01

The in vitro star system used for sunscreen UVA-testing is not an absolute measure of skin protection being a ratio of the total integrated UVA/UVB absorption. The in vivo persistent-pigment-darkening method requires human volunteers. We investigated the use of the ESR-detectable DMPO protein radical-adduct in solar-simulator-irradiated skin substitutes for sunscreen testing. Sunscreens SPF rated 20+ with UVA protection, reduced this adduct by 40-65% when applied at 2 mg/cm(2). SPF 15 Organic UVA-UVB (BMDBM-OMC) and TiO(2)-UVB filters and a novel UVA-TiO(2) filter reduced it by 21, 31 and 70% respectively. Conventional broad-spectrum sunscreens do not fully protect against protein radical-damage in skin due to possible visible-light contributions to damage or UVA-filter degradation. Anisotropic spectra of DMPO-trapped oxygen-centred radicals, proposed intermediates of lipid-oxidation, were detected in irradiated sunscreen and DMPO. Sunscreen protection might be improved by the consideration of visible-light protection and the design of filters to minimise radical leakage and lipid-oxidation.

Generation of hydroxyl radicals by urban suspended particulate air matter. The role of iron ions

Science.gov (United States)

Valavanidis, Athanasios; Salika, Anastasia; Theodoropoulou, Anna

Recent epidemiologic studies showed statistical associations between particulate air pollution in urban areas and increased morbidity and mortality, even at levels well within current national air quality standards. Inhalable particulate matter (PM 10) can penetrate into the lower airways where they can cause acute and chronic lung injury by generating toxic oxygen free radicals. We tested inhalable total suspended particulates (TSP) from the Athens area, diesel and gasoline exhaust particles (DEP and GED), and urban street dusts, by Electron Paramagnetic Resonance (EPR). All particulates can generate hydroxyl radicals (HO ṡ), in aqueous buffered solutions, in the presence of hydrogen peroxide. Results showed that oxidant generating activity is related with soluble iron ions. Leaching studies showed that urban particulate matter can release large amounts of Fe 3+ and lesser amounts of Fe 2+, as it was shown from other studies. Direct evidence of HO ṡ was confirmed by spin trapping with DMPO and measurement of DMPO-OH adduct by EPR. Evidence was supported with the use of chelator (EDTA), which increases the EPR signal, and the inhibition of the radical generating activity by desferrioxamine or/and antioxidants ( D-mannitol, sodium benzoate).

Antioxidant capacity of the leaf extract obtained from Arrabidaea chica cultivated in Southern Brazil.

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Jackeline Tiemy Guinoza Siraichi

Full Text Available Arrabidaea chica leaf extract has been used by people as an anti-inflammatory and astringent agent as well as a remedy for intestinal colic, diarrhea, leucorrhea, anemia, and leukemia. A. chica is known to be a good producer of phenolics. Therefore, in the present study, we investigated its antioxidant activity. The phenolic composition of A. chica leaves was studied by liquid chromatography coupled to diode array detection (LC-DAD and liquid chromatography coupled to electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS, and isoscutellarein, 6-hydroxyluteolin, hispidulin, scutellarein, luteolin, and apigenin were identified. The extract from leaves of A. chica was tested for antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH method, β-carotene bleaching test, and total reactive antioxidant potential (TRAP method. The crude extract quenched DPPH free radicals in a dose-dependent manner, and the IC50 of the extract was 13.51 µg/mL. The β-carotene bleaching test showed that the addition of the A. chica extract in different concentrations (200 and 500 µg/mL prevented the bleaching of β-carotene at different degrees (51.2% ±3.38% and 94% ±4.61%, respectively. The TRAP test showed dose-dependent correlation between the increasing concentrations of A. chica extract (0.1, 0.5, and 1.0 µg/mL and the TRAP values obtained by trolox (hydro-soluble vitamin E 0.4738±0.0466, 1.981±0.1603, and 6.877±1.445 µM, respectively. The 2 main flavonoids, scutellarein and apigenin, were separated, and their antioxidant activity was found to be the same as that of the plant extract. These 2 flavonoids were quantified in the plant extract by using a validated HPLC-UV method. The results of these tests showed that the extract of A. chica had a significant antioxidant activity, which could be attributed to the presence of the mixture of flavonoids in the plant extract, with the main contribution of scutellarein and apigenin.

Antioxidant and anti-osteoporotic effects of anthraquinones and related constituents from the aqueous dissolved Aloe exudates.

Science.gov (United States)

Sun, Ya Nan; Li, Wei; Lee, Sang Hyun; Jang, Hae Dong; Ma, Jin Yeul; Kim, Young Ho

2017-12-01

In this study, 25 known anthraquinones and related compounds were isolated from aqueous dissolved Aloe exudates. The antioxidant and anti-osteoporotic activities of the isolated compounds were then investigated. Compounds 8, 11, 20, and 23 showed good antioxidant activity based on peroxyl radical-scavenging and reducing capacity assays at a concentration of 10.0 μM. Additionally, compounds 7, 9, 15-16, 18, 21-22 and 24-25 showed potent peroxyl radical-scavenging activities with values ranging from 5.28 to 14.60 at 10.0 μM. Moreover, compounds 8, 11, 15, 20 and 22 exhibited significantly suppressed tartrate-resistant acid phosphatase (TRAP) activity in nuclear factor-κB ligand-activated osteoclastic RAW 264.7 cells, with values of 125.67, 118.54, 127.64, 125.82 and 124.98%, respectively. These results indicate that Aloe is an excellent source of antioxidant and anti-osteoporotic phytochemicals.

Total antioxidant status in women with breast cancer

International Nuclear Information System (INIS)

Mahmood, I.H.; Abdullah, K.S.; Abdullah, M.S.

2009-01-01

Objective: To measure the concentration of total antioxidant status (TAS) in women with breast cancer. Methodology: This is a case control study conducted in Al-Salam Hospital and Department of Pharmacology in Mosul Medical College. Twenty women having histologically confirmed breast cancer and twenty age-matched healthy volunteer women participated in the study. Serum total antioxidant status (TAS) was measured in both groups. Results: Mean TAS of the patient group (0.91 +- 0.32 mmol/l) was significantly lower (P<0.001) than that of the control group (1.82 +- 0.14 mmol/l). Conclusion: The present study demonstrated that women with breast cancer have a low level of TAS as compared to those of healthy women. It further emphasizes the growing concern that oxidative damage may occur in those patients that exhaust the antioxidant defense of the body leading to a low levels of TAS. Administration of antioxidant supplements such as a combination of vitamins A, C and E are necessary in women at high risk of developing breast cancer or after surgery or with anticancer drugs. (author)

Antioxidant activity evaluation of new dosage forms as vehicles for dehydrated vegetables.

Science.gov (United States)

Romero-de Soto, María Dolores; García-Salas, Patricia; Fernández-Arroyo, Salvador; Segura-Carretero, Antonio; Fernández-Campos, Francisco; Clares-Naveros, Beatriz

2013-06-01

A dehydrated vegetables mixture loaded in four pharmaceutical dosage forms as powder, effervescent granulate, sugar granulate and gumdrops were investigated for their antioxidant capacity using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging capacity assay, oxygen radical absorbance capacity assay and ferric reducing antioxidant potential assay. Total phenolic content of dehydrated vegetables powder mixture was also measured by the Folin-Ciocalteu method, so as to evaluate its contribution to their total antioxidant function. The effect of different temperatures on stability of these systems after 90 days storage was also evaluated. These formulations presented strong antioxidant properties and high phenolic content (279 mg gallic acid equivalent/g of sample) and thus could be potential rich sources of natural antioxidants. Antioxidant properties differed significantly among selected formulations (p forms are new and innovative approach for vegetable intakes in population with special requirements providing an improvement in the administration of vegetables and fruits.

Decreased total antioxidant levels and increased oxidative stress in ...

African Journals Online (AJOL)

21–25 ... Decreased total antioxidant levels and increased oxidative stress in South ... antioxidant-rich diet and lifestyle changes in T2DM patients would help to avert the .... glycation of proteins and the formation of advanced glycosylation.

ESR and spin-trapping study of room-temperature radicals in γ-irradiated polycrystalline pyrimidine nucleotides

International Nuclear Information System (INIS)

Zhang, Z.; Kuwabara, M.; Yoshii, G.

1983-01-01

Free radicals produced in γ-irradiated polycrystalline 5'-dCMP (free acid and 2Na), 3'-CMP (free acid and Li), and 5'-UMP (2Na) were studied by ESR and spin-trapping. The results were compared with those of previous single-crystal studies. Furthermore, attempts to identify free radicals in γ-irradiated 5'-dUMP (2Na), 5'-CMP (free acid and 2Na), and 3'-UMP (Na), which have not been the subject of single-crystal studies to date, were made. After γ-irradiation at room temperature to a dose of 100 kGy, the polycrystalline samples were dissolved in aqueous solutions of t-nitrosobutane in the presence or absence of oxygen. The presence or absence of oxygen was helpful in analyzing the presence of more than one radical species. Thus two types of radicals could be established for all samples. Radical -C 5 H-C 6 H 2 -, formed by H addition to the double bond of the base, was observed in the presence of oxygen, and radical -C/sub 5'/H 2 , formed by the transformation of the radical due to loss of an H atom at the C/sub 5'/ position of the sugar moiety, was observed in the absence of oxygen. In some cases, radicals located at the C/sub 1'/, C/sub 4'/, and C/sub 5'/ of the sugar moiety were tentatively identified. For the ESR spectrum associated with radical at C/sub 1'/ the possibility of another explanation was also discussed in relation to the spectrum due to radical at C 5 of the base. Radical -C 5 H 2 -C 6 H-, formed by H addition to the double bond of the base, was not identified

A new face of phenalenyl-based radicals in the transition metal-free C-H arylation of heteroarenes at room temperature: trapping the radical initiator via C-C σ-bond formation.

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Ahmed, Jasimuddin; P, Sreejyothi; Vijaykumar, Gonela; Jose, Anex; Raj, Manthan; Mandal, Swadhin K

2017-11-01

The radical-mediated transition metal-free approach for the direct C-H bond functionalization of arenes is considered as a cost effective alternative to transition metal-based catalysis. An organic ligand-based radical plays a key role by generating an aryl radical which undergoes a subsequent functionalization process. The design principle of the present study takes advantage of a relatively stable odd alternant hydrocarbon-based phenalenyl (PLY) radical. In this study, the first transition metal-free catalyzed direct C-H arylation of a variety of heteroarenes such as azoles, furan, thiophene and pyridine at room temperature has been reported using a phenalenyl-based radical without employing any photoactivation step. This protocol has been successfully applied to the gram scale synthesis of core moieties of bioactive molecules. The phenalenyl-based radical initiator has been characterized crystallographically by trapping it via the formation of a C-C σ-bond between the phenalenyl radical and solvent-based radical species.

Comparative Analysis of γ-Oryzanol, β-Glucan, Total Phenolic Content and Antioxidant Activity in Fermented Rice Bran of Different Varieties.

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Jung, Tae-Dong; Shin, Gi-Hae; Kim, Jae-Min; Choi, Sun-Il; Lee, Jin-Ha; Lee, Sang Jong; Park, Seon Ju; Woo, Koan Sik; Oh, Sea Kwan; Lee, Ok-Hawn

2017-06-03

Rice bran, a by-product derived from processing rice, is a rich source of bioactive compounds. Recent studies have suggested that the fermentation can improve their biological activities. This study aimed to determined the level of γ-oryzanol, β-glucan and total phenol contents of fermented rice bran from 21 Korean varieties, as well as to evaluate their antioxidant activities. We also assessed the validation of the analytical method for determining γ-oryzanol content in fermented rice brans. Among the fermented rice brans, the Haedam rice bran contained the highest level of total phenol content (156.08 mg gallic acid equivalents/g), DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity (71.30%) and ORAC (Oxygen radical absorbance capacity) value (1101.31 μM trolox equivalents/g). Furthermore, the fermented Migwang rice bran showed the highest level of γ-oryzanol content (294.77 ± 6.74 mg/100 g).

Investigation of Total Phenolic and Flavonoid Contents, and Evaluation of Antimicrobial and Antioxidant Activities from Baeckea frutescens Extracts

Science.gov (United States)

Nisa, K.; Nurhayati, S.; Apriyana, W.; Indrianingsih, A. W.

2017-12-01

Baeckea frutescens L. is a medicinal plant endemic to the tropical area and it has been used by locals for topical and oral ailments. This study investigated total phenolic and flavonoid contents and also evaluated in vitro antimicrobial and antioxidant activities of of Baeckea frutescens crude extracts. These extracts were assessed for their antibacterial activities against strains of Escherichia coli, Staphylococcus aureus, Salmonella thypii, and Pseudomonas aureginosa by the broth micro-dilution methods using a modified tetrazolium-based colorimetric assay (3-(4, 5-dimethylthiazol)-2, 5-diphenyl tetrazolium bromide (MTT) assay). Baeckea frutescens crude extracts were also tested against the stable DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free-radical. The results indicated that Baeckea frutescens water and ethanol extracts possesed remarkable antibacterial activity with the minimum inhibitory concentration less than 100 μg/ml against Escherichia coli and Salmonella thypi. On the evaluation of the antioxidant activity via DPPH assay, Baeckea frutescens ethanol extracts exhibited a good antioxidant activity with IC50 less than 50 μg/ml and Baeckea frutescens water extracts showed a moderate antioxidant activity with IC50 less than 100 μg/ml.

Pharmacokinetics and Plasma Cellular Antioxidative Effects of Flavanols After Oral Intake of Green Tea Formulated with Vitamin C and Xylitol in Healthy Subjects.

Science.gov (United States)

Son, Yu-Ra; Park, Tae-Sik; Shim, Soon-Mi

2016-02-01

This study aimed to test whether green tea formulated with vitamin C and xylitol (GTVX) could improve absorption of flavanols and total antioxidant activity (TAC) of plasma compared with green tea only (GT) in healthy subjects. The total radical-trapping antioxidant parameter method was used to measure the TAC of plasma. Cmax, Tmax, and area under the curve (AUC) of flavanols in plasma after consumption of GTVX were 5980.58 μg/mL, 2.14 h, and 18,915.56 h·μg/mL, respectively, indicating that GTVX showed significantly higher AUC than GT (13,855.43 μg/mL). The peak TACs occurred at 3 and 0.5 h after intake of GT and GTVX, respectively. The TAC of plasma was found to be significantly higher in GTVX than in GT at each time point. This study suggests that formulating green tea with vitamin C and xylitol could increase the absorption of flavanols in green tea, enhancing cellular antioxidative effects.

ANTIOXIDANT PROPERTIES OF THE BESTSELLING SLOVAK RED WINES

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Silvia Čéryová

2012-02-01

Full Text Available Antioxidants are specific substances that oxidize themselves and in this way they protect other sensitive bioactive food components against destruction. At the same time they restrict the activity of free radicals and change them to less active forms. Large group of antioxidants are polyphenols, which affect sensory properties of fruit, vegetable and some drinks, like colour (anthocyans, taste (flavonoids or odour (phenols. The significant source of polyphenolic compounds are wines. Polyphenols (in optimal amount and combination, found mainly in red wines, have very complex (positive effects on organism. The aim of this work was to determine chosen antioxidant properties of the best-selling quality red wines - Blaufränkisch and St. Laurent, originating from different Slovak vineyard areas. Total polyphenols content was determined with phenol Folin-Ciocalteau´s reagent and antioxidant activity was determined using DPPH stable free radical. Both parameters were determined by UV-VIS absorption spectrometry. The determined total polyphenol contents in observed wines were within the interval 1579 – 2734 mg.L-1 (Blaufränkisch, respectively 1409 – 3276 mg.L-1 (St. Laurent. Antioxidant activity in wines was within the interval 80.2 – 86.4 % (Blaufränkisch, respectively 71.0 – 84.8 % (St. Laurent. The differences between results of measured antioxidant properties (total polyphenol contents and antioxidant activities of the wines originating from some vineyard Slovak areas were statistically significant.

Antioxidant Capacity, Anthocyanins, and Total Phenols of Wild and Cultivated Berries in Chile Capacidad Antioxidante, Antocianinas y Fenoles Totales de Berries Silvestres y Cultivados en Chile

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Jaime Guerrero C

2010-12-01

Full Text Available It is possible to incorporate a lot of natural antioxidants into the human organism by consuming berries which can prevent diseases generated by the action of free radicals. Antioxidants neutralize free radicals and thus protect the organism from the oxidative damage of lipids, proteins, and nucleic acids. Berries stand out as one of the richest sources of antioxidant phytonutrients among various fruits and vegetables. The objective of this research was to determine antioxidant capacity (AC, total anthocyanins (TA, and total phenols (TP of wild and cultivated berries in different localities of La Araucanía and Los Ríos Regions in Chile. These parameters were analyzed by using the free radical 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH method, pH-differential, and Folin-Ciocalteu method. Percentages of DPPH discoloration of different berries studied were between 67.8% and 95.3% for red sarsaparilla and rosehip, respectively. Maqui berries showed a significantly higher TA content (2240.2 and 1445.3 mg L-1 cyanidin 3-glucoside than other berries, and a mean for all berries of 335.5 mg L-1. Higher phenol content levels were obtained in two cultivars of saskatoon (773.9 and 1001.9 mg L-1 gallic acid and wild rosehip (1457.0 and 1140.4 mg L-1 gallic acid. We conclude that there are significant differences in antioxidant capacity of wild and cultivated Chilean berries in this study which show a strong correlation between AC and TP content.Por medio del consumo de berries es posible incorporar al organismo una gran cantidad de antioxidantes capaces de prevenir múltiples enfermedades generadas por la acción de los radicales libres. Los antioxidantes actúan neutralizando los radicales libres y de esta forma protegen al organismo del daño oxidativo de lípidos, proteínas y ácidos nucleicos. Entre variadas frutas y hortalizas, se destacan los berries como una de las fuentes más ricas en fitonutrientes antioxidantes. El objetivo de esta investigaci

Application of Attenuated Total Reflectance-Fourier Transformed Infrared (ATR-FTIR) Spectroscopy To Determine the Chlorogenic Acid Isomer Profile and Antioxidant Capacity of Coffee Beans.

Science.gov (United States)

Liang, Ningjian; Lu, Xiaonan; Hu, Yaxi; Kitts, David D

2016-01-27

The chlorogenic acid isomer profile and antioxidant activity of both green and roasted coffee beans are reported herein using ATR-FTIR spectroscopy combined with chemometric analyses. High-performance liquid chromatography (HPLC) quantified different chlorogenic acid isomer contents for reference, whereas ORAC, ABTS, and DPPH were used to determine the antioxidant activity of the same coffee bean extracts. FTIR spectral data and reference data of 42 coffee bean samples were processed to build optimized PLSR models, and 18 samples were used for external validation of constructed PLSR models. In total, six PLSR models were constructed for six chlorogenic acid isomers to predict content, with three PLSR models constructed to forecast the free radical scavenging activities, obtained using different chemical assays. In conclusion, FTIR spectroscopy, coupled with PLSR, serves as a reliable, nondestructive, and rapid analytical method to quantify chlorogenic acids and to assess different free radical-scavenging capacities in coffee beans.

Antioxidant activity profiling by spectrophotometric methods of aqueous methanolic extracts of Helichrysum stoechas subsp. rupestre and Phagnalon saxatile subsp. saxatile.

Science.gov (United States)

Haddouchi, Farah; Chaouche, Tarik Mohammed; Ksouri, Riadh; Medini, Faten; Sekkal, Fatima Zohra; Benmansour, Abdelhafid

2014-06-01

The aqueous methanolic extracts of two plants from Algeria, Helichrysum stoechas subsp. rupestre and Phagnalon saxatile subsp. saxatile, were investigated for their antioxidant activity. Total phenolics, flavonoids, and tannins were determined by spectrophotometric techniques. In vitro antioxidant and radical scavenging profiling was determined by spectrophotometric methods, through: Total antioxidant capacity, and radical scavenging effects by the DPPH and ABTS methods, reducing and chelating power, and blanching inhibition of the β-carotene. All of the extracts showed interesting antioxidant and radical scavenging activity. The highest contents in phenolics, tannins, and the highest total antioxidant capacity as gallic acid equivalents of 97.5 ± 0.33 mg GAE/g DW was obtained for the flowers of H. stoechas subsp. rupestre extract in the phosphomolybdenum assay. An extract of the leafy stems of P. saxatile subsp. saxatile revealed the highest content of flavonoids, and the highest antioxidant activity by the radical scavenging and β-carotene assays when compared with standards. The best activity was by the scavenging radical DPPH with an IC50 value of 5.65 ± 0.10 μg·mL(-1). The studied medicinal plants could provide scientific evidence for some traditional uses in the treatment of diseases related to the production of reactive oxygen species (ROS) and oxidative stress. Copyright © 2014 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Antioxidant Activity of Three Honey Samples in relation with Their Biochemical Components

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Lee Suan Chua

2013-01-01

Full Text Available The antioxidant activities based on the free radical scavenging, reducing power, and bleaching inhibition were investigated for the three commonly used honeys in Malaysia, namely, tualang, gelam, and acacia honey. The antioxidant capacity of the honey samples was correlated with their biochemical constituents such as total phenol, total flavonoid content, and total water-soluble vitamins (vitamin B1, B2, B3, B9, B12, and vitamin C. The total flavonoid content of honey samples was strongly correlated with the three antioxidative processes (–0.9910. In contrast, the total water-soluble vitamins was found to be well correlated with the free radical scavenging activity (. Vitamin B3 was likely to be in the highest concentration, which covered for 69–80% of the total vitamin content. A number of five phenolic acids, three flavonoids, and two organic acids had also been detected from the honey samples using UPLC-MS/MS, without sugar-removal procedure.

Hepatoprotective and antioxidant capacity of Melochia corchorifolia extracts.

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Rao, B Ganga; Rao, Y Venkateswara; Rao, T Mallikarjuna

2013-07-01

To evaluate hepato protective and antioxidant capacity of Melochia corchorifolia (M. corchorifolia) aerial part extracts. Antioxidant activity was evaluated by using three free radicals (Superoxide, Hydroxyl and DPPH) and hepatoprotective activity was assessed against CCl4 induced liver intoxication in rats. The extracts produced concentration dependent percentage protection in decrease of serum enzymes and percentage inhibition on free radicals. Among all extracts methanol extract showed better activity with percentage protection of SGOT (78.98%), SGPT (79.65%), ALP (82.48%) and total bilirubin (80.0%) levels against CCl4 liver intoxication and also methanolic extract showed better activity with IC50 values on superoxide, hydroxyl and DPPH radicals were 127 μ g, 240 μ g and 179 μ g. From the results obtained during the study it could be concluded that M. corchorifolia aerial part extracts have antioxidant and hepatoprotective components. Further study is necessary for isolation and characterization of bioactive molecules which are responsible for hepatoprotective and antioxidant activity. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Evaluation of antioxidant potential of citrus peel extracts

International Nuclear Information System (INIS)

Chatha, S.A.S.; Hussain, A.I.; Asi, M.R.

2011-01-01

The antioxidant potential of different solvent extracts of three different locally grown citrus varieties; grape fruit, lemon and mussambi, was assessed using some antioxidant assays like estimation of total phenolic contents (TPC), total flavonoids contents (TFC), percentage inhibition of linoleic acid oxidation and DPPH free radical scavenging capacity. The yield of extracts was found in the range of 17.92-30.8%. TPC, TFC, percent inhibition of linoleic acid oxidation and DPPH radical scavenging capacity of different citrus peel extracts were found in range of 2.72 - 3.77 g/100g as Gallic Acid Equivalent (GAE), 2.20-2.98 g/100g as Catechine Equivalent (CE), 68.20 - 91.78% and 19.53 - 41.88 mg/mL, respectively. Statistical analysis showed significant (p < 0.05) variations in the yield and antioxidant potentials of the extracts with respect to different species and solvent systems. From the results it is reasonable to say that methanolic extracts of citrus peels have exhibited varying degree of antioxidant potentials. (author)

Quantification of Phenolic Compounds and In Vitro Radical Scavenging Abilities with Leaf Extracts from Two Varieties of Psidium guajava L.

Science.gov (United States)

Camarena-Tello, Julio César; Martínez-Flores, Héctor Eduardo; Garnica-Romo, Ma Guadalupe; Padilla-Ramírez, José Saúl; Saavedra-Molina, Alfredo; Alvarez-Cortes, Osvaldo; Bartolomé-Camacho, María Carmen; Rodiles-López, José Octavio

2018-02-27

Guava leaf ( Psidium guajava L.) extracts are used in both traditional medicine and the pharmaceutical industry. The antioxidant compounds in P. guajava leaves can have positive effects including anti-inflammatory, anti-hyperglycemic, hepatoprotective, analgesic, anti-cancer effects, as well as protecting against cardiovascular diseases. In the present study, phenolic compounds and in vitro antioxidant capacity were measured in extracts obtained with polar and non-polar solvents from leaves of two varieties of guava, Calvillo Siglo XXI and Hidrozac. The quantity of total phenolics and total flavonoids were expressed as equivalents of gallic acid and quercetin, respectively. Hydroxyl radical, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and Oxygen Radical Absorbance Capacity using fluorescein (ORAC-FL) in vitro tests were used to assess the radical scavenging abilities of the extracts. The total phenolics were higher in the aqueous fraction of the variety Calvillo Siglo XXI, while in the Hidrozac variety total phenolics were higher in the acetone and chloroform fractions. Total flavonoids were higher in all fractions in the variety Calvillo Siglo XXI. Total phenolics showed a highly positive correlation for ORAC-FL, and a moderately positive correlation with hydroxyl radicals. Finally, total flavonoids showed a slightly positive correlation for ORAC-FL and hydroxyl radicals. Both varieties of guava leaf extract showed excellent antioxidant properties.

Quantification of Phenolic Compounds and In Vitro Radical Scavenging Abilities with Leaf Extracts from Two Varieties of Psidium guajava L.

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Julio César Camarena-Tello

2018-02-01

Full Text Available Guava leaf (Psidium guajava L. extracts are used in both traditional medicine and the pharmaceutical industry. The antioxidant compounds in P. guajava leaves can have positive effects including anti-inflammatory, anti-hyperglycemic, hepatoprotective, analgesic, anti-cancer effects, as well as protecting against cardiovascular diseases. In the present study, phenolic compounds and in vitro antioxidant capacity were measured in extracts obtained with polar and non-polar solvents from leaves of two varieties of guava, Calvillo Siglo XXI and Hidrozac. The quantity of total phenolics and total flavonoids were expressed as equivalents of gallic acid and quercetin, respectively. Hydroxyl radical, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS, 2,2-diphenyl-1-picrylhydrazyl (DPPH, and Oxygen Radical Absorbance Capacity using fluorescein (ORAC-FL in vitro tests were used to assess the radical scavenging abilities of the extracts. The total phenolics were higher in the aqueous fraction of the variety Calvillo Siglo XXI, while in the Hidrozac variety total phenolics were higher in the acetone and chloroform fractions. Total flavonoids were higher in all fractions in the variety Calvillo Siglo XXI. Total phenolics showed a highly positive correlation for ORAC-FL, and a moderately positive correlation with hydroxyl radicals. Finally, total flavonoids showed a slightly positive correlation for ORAC-FL and hydroxyl radicals. Both varieties of guava leaf extract showed excellent antioxidant properties.

Quantification of Phenolic Compounds and In Vitro Radical Scavenging Abilities with Leaf Extracts from Two Varieties of Psidium guajava L.

Science.gov (United States)

Martínez-Flores, Héctor Eduardo; Garnica-Romo, Ma. Guadalupe; Padilla-Ramírez, José Saúl; Saavedra-Molina, Alfredo; Alvarez-Cortes, Osvaldo; Bartolomé-Camacho, María Carmen; Rodiles-López, José Octavio

2018-01-01

Guava leaf (Psidium guajava L.) extracts are used in both traditional medicine and the pharmaceutical industry. The antioxidant compounds in P. guajava leaves can have positive effects including anti-inflammatory, anti-hyperglycemic, hepatoprotective, analgesic, anti-cancer effects, as well as protecting against cardiovascular diseases. In the present study, phenolic compounds and in vitro antioxidant capacity were measured in extracts obtained with polar and non-polar solvents from leaves of two varieties of guava, Calvillo Siglo XXI and Hidrozac. The quantity of total phenolics and total flavonoids were expressed as equivalents of gallic acid and quercetin, respectively. Hydroxyl radical, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and Oxygen Radical Absorbance Capacity using fluorescein (ORAC-FL) in vitro tests were used to assess the radical scavenging abilities of the extracts. The total phenolics were higher in the aqueous fraction of the variety Calvillo Siglo XXI, while in the Hidrozac variety total phenolics were higher in the acetone and chloroform fractions. Total flavonoids were higher in all fractions in the variety Calvillo Siglo XXI. Total phenolics showed a highly positive correlation for ORAC-FL, and a moderately positive correlation with hydroxyl radicals. Finally, total flavonoids showed a slightly positive correlation for ORAC-FL and hydroxyl radicals. Both varieties of guava leaf extract showed excellent antioxidant properties. PMID:29495514

Antibacterial and antioxidant activities of the essential oils and ...

African Journals Online (AJOL)

The present study deals with the evaluation of the in vitro antioxidant and antibacterial activity of phenolic extracts and essential oils of two medicinal and aromatic plants Zygophyllum album and Myrtus communis by using the 2,2- diphenyl-2-picrylhydrazyl radical, total antioxidant power and agar diffusion methods and ...

Prooxidant/Antioxidant Ratio (ProAntidex as a Better Index of Net Free Radical Scavenging Potential

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Hwee Ming Cheng

2010-11-01

Full Text Available The antioxidant activity of several Malaysian plant extracts was analyzed simultaneously with their pro-oxidant capacity. This ratio represents an index (ProAntidex of the net free radical scavenging ability of whole plant extracts. We observed that ethanolic extracts of Nephelium lappaceum peel, Fragaria x ananassa leaf, Lawsonia inermis leaf, Syzygium aqueum leaf and grape seed had a lower Pro-Antidex than the commercially available Emblica™ extract which is an antioxidant agent with very low pro-oxidant activity. Among the aqueous extracts, Lawsonia inermis leaf, Nephelium mutobile leaf and grape seed had lower pro-oxidant activity compared to the Emblica™ extract. Among these extracts, aqueous extract of Nephelium mutobile leaf had a very low index of 0.05 compared to 0.69 for Emblica™. Most of the extracts had a far lower ProAntidex compared to the Vitamin C. The index enables us to identify extracts with high net free radical scavenging activity potential. The ProAntidex is beneficial as a screening parameter to the food industries and healthcare.

Phytochemical Composition and Antioxidant Potential of Ruta graveolens L. In Vitro Culture Lines

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Renuka Diwan

2012-01-01

Full Text Available Ruta graveolens L. is a medicinal plant used in traditional systems of medicine for treatment of psoriasis, vitiligo, leucoderma, and lymphomas with well-known anti-inflammatory and anticancer properties. Therefore antioxidant potential of R. graveolens (in planta and in vitro was investigated. As antioxidants present in plant extracts are multifunctional, their activity and mechanism depends on the composition and conditions of the test system. Therefore, the total antioxidant capacity was evaluated using assays that detect different antioxidants: free radical scavenging (DPPH and ABTS, transition metal ion reduction (phosphomolybdenum assay, reducing power, and nitric oxide reduction. Content of furanocoumarin-bergapten in the extracts showed good corelation with free radical scavenging, transition metal reduction and reducing power, while total phenolic content showed good corelation with nitric oxide reduction potential. Antioxidant activity of in vitro cultures was significantly higher compared to in vivo plant material. The present study is the first report on comprehensive study of antioxidant activity of R. graveolens and its in vitro cultures.

Antioxidant Capacity and Proanthocyanidin Composition of the Bark of Metasequoia glyptostroboides.

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Chen, Fengyang; Zhang, Lin; Zong, Shuling; Xu, Shifang; Li, Xiaoyu; Ye, Yiping

2014-01-01

Metasequoia glyptostroboides Hu et Cheng is the only living species in the genus Metasequoia Miki ex Hu et Cheng (Taxodiaceae), which is well known as a "living fossil" species. In the Chinese folk medicine, the leaves and bark of M. glyptostroboides are used as antimicrobic, analgesic, and anti-inflammatory drug for dermatic diseases. This study is the first to report the free radical scavenging capacity, antioxidant activity, and proanthocyanidin composition of the bark of M. glyptostroboides. We observed total of six extracts and fractions, which were easily obtained by water-ethanol extraction and followed by a further separation with D101 resin column chromatography, had significant DPPH radical, superoxide anion radical, and hydroxyl radical scavenging capacity, total antioxidative capacity (T-AOC), lipid peroxidation inhibitory activity, and metal ions chelating capacity. The fraction MGEB, which was obtained by 60% ethanol extraction and followed by a further separation with D101 resin column chromatograph, possessed the highest proanthocyanidin content and the highest free radical scavenging and antioxidant activities. Furthermore, MGEB could significantly protect against CCl4 induced acute liver injury through inhibition of oxidative stress in mice. In addition, ten proanthocyanidins were isolated from MGEB, and six of them were firstly reported from this plant.

Antioxidant Capacity and Proanthocyanidin Composition of the Bark of Metasequoia glyptostroboides

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Fengyang Chen

2014-01-01

Full Text Available Metasequoia glyptostroboides Hu et Cheng is the only living species in the genus Metasequoia Miki ex Hu et Cheng (Taxodiaceae, which is well known as a “living fossil” species. In the Chinese folk medicine, the leaves and bark of M. glyptostroboides are used as antimicrobic, analgesic, and anti-inflammatory drug for dermatic diseases. This study is the first to report the free radical scavenging capacity, antioxidant activity, and proanthocyanidin composition of the bark of M. glyptostroboides. We observed total of six extracts and fractions, which were easily obtained by water-ethanol extraction and followed by a further separation with D101 resin column chromatography, had significant DPPH radical, superoxide anion radical, and hydroxyl radical scavenging capacity, total antioxidative capacity (T-AOC, lipid peroxidation inhibitory activity, and metal ions chelating capacity. The fraction MGEB, which was obtained by 60% ethanol extraction and followed by a further separation with D101 resin column chromatograph, possessed the highest proanthocyanidin content and the highest free radical scavenging and antioxidant activities. Furthermore, MGEB could significantly protect against CCl4 induced acute liver injury through inhibition of oxidative stress in mice. In addition, ten proanthocyanidins were isolated from MGEB, and six of them were firstly reported from this plant.

Supercritical carbon dioxide extraction of antioxidants from rosemary (Rosmarinus officinalis L. and sage (Salvia officinalis L.

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JASNA IVANOVIĆ

2009-07-01

Full Text Available The aim of the present study was to isolate and characterize antioxidant extracts obtained from dried leaves of rosemary (Rosmarinus officinalis L. and sage (Salvia officinalis L., originating from the southern Balkan Region. The antioxidant fraction was isolated from the plant material by supercritical carbon dioxide (SC-CO2 fractional extraction under a pressure of 30 MPa and at temperatures of 40 and 100 °C. In the present study, kinetic data and yields of antioxidant extracts obtained from dried leaves of rosemary and sage under different conditions were determined. Electron spin resonance (ESR spectroscopy assay on the ability of the extracts to scavenge stable 2,2-diphenyl-1-picrylhydrazyl (DPPH free radicals and reactive hydroxyl radicals during the Fenton reaction trapped by 5,5-dimethyl-1-pyrroline-N-oxide (DMPO showed that the investigated extracts had antioxidant activity comparable to that of butylated hydroxyanisole (BHA and commercial rosemary extract. The antioxidant fractions isolated at the higher temperature had higher antioxidant activities. A tentative analysis of the chemical composition of the antioxidant fractions obtained at the higher temperature was accomplished by LC-DAD and LC-MS analytical methods. Abietane-type diterpenoids, flavonoids and fatty acids were identified in the SC-CO2 extract of rosemary and sage.

Use of different spices as potential natural antioxidant additives on cooked beans (Phaseolus vulgaris). Increase of DPPH radical scavenging activity and total phenolic content.

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Pereira, Marina Pelincer; Tavano, Olga Luisa

2014-12-01

Herbs and spices, excellent sources of phenolic compounds, can be considered potential antioxidant additives. The use of spices must strike a balance between their potential antioxidant capabilities during preparation and the flavor acceptance, in order to avoid rejection of the food. The aimed of this study is to evaluate the influence of different spices and their concentrations on cooked common beans, focusing its potential as antioxidant additives. Onion, parsley, spring onion, laurel and coriander increased the antioxidant activity of preparation when used at 7.96 g of onion, 1.06 g parsley, 3.43 g spring onion, 0.25 g laurel (dry leaves), and 0.43 g coriander/100 g of cooked beans. Besides, these spices concentrations enhance total phenolics and alter the mixture protein digestibility minimally. For garlic samples it was not possible to establish a concentration that increases the antioxidant activity of cooked beans.

In vitro total phenolics, flavonoids contents and antioxidant activity of essential oil, various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.

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Hossain, M Amzad; Shah, Muhammad Dawood; Gnanaraj, Charles; Iqbal, Muhammad

2011-09-01

To detect the in vitro total phenolics, flavonoids contents and antioxidant activity of essential oil, various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah. The dry powder leaves of Tetrastigma were extracted with different organic solvent such as hexane, ethyl acetate, chloroform, butanol and aqueous methanol. The total phenolic and total flavonoids contents of the essential oil and various organic extracts such as hexane, ethyl acetate, chloroform, butanol and aqueous ethanol were determined by Folin - Ciocalteu method and the assayed antioxidant activity was determined in vitro models such as antioxidant capacity by radical scavenging activity using α, α-diphenyl- β-picrylhydrazyl (DPPH) method. The total phenolic contents of the essential oil and different extracts as gallic acid equivalents were found to be highest in methanol extract (386.22 mg/g) followed by ethyl acetate (190.89 mg/g), chloroform (175.89 mg/g), hexane (173.44 mg/g), and butanol extract (131.72 mg/g) and the phenolic contents not detected in essential oil. The antioxidant capacity of the essential oil and different extracts as ascorbic acid standard was in the order of methanol extract > ethyl acetate extract >chloroform> butanol > hexane extract also the antioxidant activity was not detected in essential oil. The findings show that the extent of antioxidant activity of the essential oil and all extracts are in accordance with the amount of phenolics present in that extract. Leaves of Tetrastigma being rich in phenolics may provide a good source of antioxidant. Copyright © 2011 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Spectroscopic studies on the antioxidant activity of ellagic acid

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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.

Chemical repair of trypsin-histidinyl radical

International Nuclear Information System (INIS)

Jovanovic, S.V.; Ruvarac, I.; Jankovic, I.; Josimovic, L.

1991-01-01

Oxyl radicals, such as hydroxyl, alkoxyl and peroxyl, react with biomolecules to produce bioradicals. Unless chemically repaired by suitable antioxidants, these bioradicals form stable products. This leads to loss of biological function of parent biomolecules with deleterious biological results, such as mutagenesis and cancer. Consequently, the understanding of the mechanisms of oxyl radical damage to biomolecules and chemical repair of such damage is crucial for the development of strategies for anticarcinogenesis and radioprotection. In this study the chemical repair of the histidinyl radical generated upon the trichloromethylperoxyl radical reaction with trypsin vas investigated by gamma radiolysis. The trypsin histidinyl radical is a resonance-stabilized heterocyclic free radical which was found to be unreactive with oxygen. The efficacy of the chemical repair of the trypsin-histidinyl radical by endogenous antioxidants which are electron donors (e.g. 5-hydroxytryptophan, uric acid) is compared to that of antioxidants which are H-atom donors (e. g. glutathione). 9 refs., 2 figs., 1 tab

Total cross section for chloroflouromethanes and CClx radicals by electron impact

International Nuclear Information System (INIS)

Gupta, Dhanoj; Antony, Bobby

2013-01-01

Highlights: ► A model to find total CS for freons and CCl x by e − impact is employed. ► Complex optical potential formalism is used to find total inelastic and elastic CS. ► Result shows very good agreement with previous data wherever available. ► Maiden attempt to find cross section for the CCl x radicals. -- Abstract: We report here the total cross section for chloroflouromethanes namely CCl 3 F (Freon 11), CCl 2 F 2 (Freon 12), CClF 3 (Freon 13), CCl 4 and CCl x (x = 1–3), radicals by electron impact 50 to 5000 eV. The total inelastic and elastic cross sections are obtained employing a complex optical potential formalism and solving the Schrödinger equation through partial wave analysis. The total cross section is obtained as the sum of total inelastic and elastic cross sections. The results obtained are compared with the existing experimental and theoretical data, wherever available. The present result shows reasonable agreement with previous data. For the CCl x radicals, we have predicted the total cross sections for the first time. The data reported here has immense interest to atmospheric and technological plasma modelling

Comparative Analysis of γ-Oryzanol, β-Glucan, Total Phenolic Content and Antioxidant Activity in Fermented Rice Bran of Different Varieties

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Tae-Dong Jung

2017-06-01

Full Text Available Rice bran, a by-product derived from processing rice, is a rich source of bioactive compounds. Recent studies have suggested that the fermentation can improve their biological activities. This study aimed to determined the level of γ-oryzanol, β-glucan and total phenol contents of fermented rice bran from 21 Korean varieties, as well as to evaluate their antioxidant activities. We also assessed the validation of the analytical method for determining γ-oryzanol content in fermented rice brans. Among the fermented rice brans, the Haedam rice bran contained the highest level of total phenol content (156.08 mg gallic acid equivalents/g, DPPH (2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (71.30% and ORAC (Oxygen radical absorbance capacity value (1101.31 μM trolox equivalents/g. Furthermore, the fermented Migwang rice bran showed the highest level of γ-oryzanol content (294.77 ± 6.74 mg/100 g.

Phenolic Compounds of Cereals and Their Antioxidant Capacity.

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Van Hung, Pham

2016-01-01

Phenolic compounds play an important role in health benefits because of their highly antioxidant capacity. In this review, total phenolic contents (TPCs), phenolic acid profile and antioxidant capacity of the extracted from wheat, corn, rice, barley, sorghum, rye, oat, and millet, which have been recently reported, are summarized. The review shows clearly that cereals contain a number of phytochemicals including phenolics, flavonoids, anthocyanins, etc. The phytochemicals of cereals significantly exhibit antioxidant activity as measured by trolox equivalent antioxidant capacity (TEAC), 2,2-diphenyl-1-picrylhydrazyl radical scavenging, reducing power, oxygen radical absorbance capacity (ORAC), inhibition of oxidation of human low-density lipoprotein (LDL) cholesterol and DNA, Rancimat, inhibition of photochemilumenescence (PCL), and iron(II) chelation activity. Thus, the consumption of whole grains is considered to have significantly health benefits in prevention from chronic diseases such as cardiovascular disease, diabetes, and cancer because of the contribution of phenolic compounds existed. In addition, the extracts from cereal brans are considered to be used as a source of natural antioxidants.

The Role of Electron Transport and Trapping in MOS Total-Dose Modeling

International Nuclear Information System (INIS)

Fleetwood, D.M.; Winokur, P.S.; Riewe, L.C.; Flament, O.; Paillet, P.; Leray, J.L.

1999-01-01

Radiation-induced hole and electron transport and trapping are fundamental to MOS total-dose models. Here we separate the effects of electron-hole annihilation and electron trapping on the neutralization of radiation-induced charge during switched-bias irradiation for hard and soft oxides, via combined thermally stimulated current (TSC) and capacitance-voltage measurements. We also show that present total-dose models cannot account for the thermal stability of deeply trapped electrons near the Si/SiO 2 interface, or the inability of electrons in deep or shallow traps to contribute to TSC at positive bias following (1) room-temperature, (2) high-temperature, or (3) switched-bias irradiation. These results require revisions of modeling parameters and boundary conditions for hole and electron transport in SiO 2 . The nature of deep and shallow electron traps in the near-interfacial SiO 2 is discussed

Changes of Major Antioxidant Compounds and Radical Scavenging Activity of Palm Oil and Rice Bran Oil during Deep-Frying

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Abdul Hamid, Azizah; Pak Dek, Mohd Sabri; Tan, Chin Ping; Mohd Zainudin, Mohd Asraf; Wee Fang, Evelyn Koh

2014-01-01

Changes in antioxidant properties and degradation of bioactives in palm oil (PO) and rice bran oil (RBO) during deep-frying were investigated. The alpha (α)-tocopherol, gamma (γ)-tocotrienol and γ-oryzanol contents of the deep-fried oils were monitored using high performance liquid chromatography, and antioxidant activity was determined using 2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity. Results revealed that the antioxidant activity of PO decreased significantly (p -oryzanol and γ-tocotrienol in RBO may have a protective effect on α-tocopherol during deep-frying. PMID:26785067

Evaluating the antioxidant and acetylcholinesterase inhibitory activity of three Centaurea species

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H. Hajimehdipoor

2014-01-01

Full Text Available Factors such as oxidative stress and reduced acetylcholine level have been implicated in Alzheimer’s disease (AD pathology and recently there has been a trend towards natural product research to find potential sources of antioxidants and acetylcholinesterase inhibitors in the plants kingdom. Centaurea is a genus with about 500 species world wild, many of them have shown to possess biologic activity; Centaurea albonites, C. aucheri and C. pseudoscabiosa are three species which little investigation has been carried out about their biological properties. In the present study, the antioxidant and acetylcholinesterase inhibitory activity of the above mentioned species have been evaluated. The ability of the total extract and methanol fraction of the plants to scavenge free radicals has been assessed through DPPH radical scavenging assay, and the acetylcholinesterase inhibitory property has been evaluated by Ellman method. The total extract of all species exhibited moderate antioxidant activity whereas the extracts of C. pseudoscabiosa showed the strongest antioxidant property; its total extract also demonstrated the highest acetylcholinesterase inhibitory activity among the evaluated samples (19.2% inhibition. The results suggest the species as potential sources of natural antioxidants which could be focused in future studies of Alzheimer’s disease.

The influence of ripening stage and cultivation system on the total antioxidant activity and total phenolic compounds of yellow passion fruit pulp.

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Macoris, Mariana S; De Marchi, Renata; Janzantti, Natália S; Monteiro, Magali

2012-07-01

This work aimed to investigate the influence of both ripening stage and cultivation system on the total phenolic compounds (TPC) and total antioxidant activity (TAA) of passion fruit pulp. TPC extraction was optimized using a 2³ central composed design. The variables were fruit pulp volume, methanol volume and extraction solution volume. TPC was determined using the Folin-Ciocalteu reaction, and TAA using the ABTS radical reaction. The conditions to extract TPC were 2 mL passion fruit pulp and 9 mL extraction solution containing 40% methanol:water (v/v). TPC values increased in the passion fruit pulp during ripening for both cultivation systems, ranging from 281.8 to 361.9 mg gallic acid L⁻¹ (P ≤ 0.05) for the organic pulp and from 291.0 to 338.6 mg gallic acid L⁻¹ (P ≤ 0.05) for the conventional pulp. TPC values increased during ripening for both organic and conventional passion fruit. The same was true for TAA values for conventional passion fruit. For organic passion fruit, however, TAA values were highest at the initial ripening stages. These results suggest that antioxidant compounds exert strong influence on the initial ripening stages for organic passion fruit, when TPC still did not reach its maximum level. Copyright © 2012 Society of Chemical Industry.

Use of rapid-scan EPR to improve detection sensitivity for spin-trapped radicals.

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Mitchell, Deborah G; Rosen, Gerald M; Tseitlin, Mark; Symmes, Breanna; Eaton, Sandra S; Eaton, Gareth R

2013-07-16

The short lifetime of superoxide and the low rates of formation expected in vivo make detection by standard continuous wave (CW) electron paramagnetic resonance (EPR) challenging. The new rapid-scan EPR method offers improved sensitivity for these types of samples. In rapid-scan EPR, the magnetic field is scanned through resonance in a time that is short relative to electron spin relaxation times, and data are processed to obtain the absorption spectrum. To validate the application of rapid-scan EPR to spin trapping, superoxide was generated by the reaction of xanthine oxidase and hypoxanthine with rates of 0.1-6.0 μM/min and trapped with 5-tert-butoxycarbonyl-5-methyl-1-pyrroline-N-oxide (BMPO). Spin trapping with BMPO to form the BMPO-OOH adduct converts the very short-lived superoxide radical into a more stable spin adduct. There is good agreement between the hyperfine splitting parameters obtained for BMPO-OOH by CW and rapid-scan EPR. For the same signal acquisition time, the signal/noise ratio is >40 times higher for rapid-scan than for CW EPR. Rapid-scan EPR can detect superoxide produced by Enterococcus faecalis at rates that are too low for detection by CW EPR. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Phytochemical screening, antioxidant activity, total phenolic and total flavonoid contents of seven local varieties of Rosa indica L.

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Zahid, Kiran; Ahmed, Maqsood; Khan, Farah

2018-05-01

Rosa indica symbol of godness and beauty known for various healing power, has astringent, sedative, anti-inflammatory and antidepressant qualities. Standard methods were used for qualitative detection of phyto-compounds, and quantitative detection of antioxidants was done using DPPH radical scavenging assay, total phenolics and total flavonoids content were expressed in mg GAE/g dry weight and mg QE/g dry weight. Results revealed phyto-compounds presence in all varieties under study however maximum % inhibition was observed by R. indica var pink perfume (94 ± 0.6) with IC50 value 0.3376 ± 0.01 mg/mL. Highest phenolic and flavonoid content was observed in the leaves extract of R. indica var cardinal red, i.e. 3.3553 ± 0.11 (ethanol) mg of Gallic acid equivalents (GAE)/g dry weight and 3.736 ± 0.001(ethanol) mg of quercetin equivalents (QE)/g dry weight, respectively, at conc. 0.125 mg/mL. Our finding provides evidence that all varieties of rose contain medicinally important bioactive compounds and justifies their use for treatment of different diseases.

In vitro evaluation of the antioxidant potential, phenolic and flavonoid contents of the stem bark ethanol extract of Anogeissus leiocarpus.

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Olugbami, J O; Gbadegesin, M A; Odunola, O A

2014-09-01

Plant-derived antioxidants with free radical scavenging activities can be relevant as chemopreventive agents against the numerous diseases associated with free radicals and reactive oxygen species. Some phytoconstituents possess antioxidant activities in biological systems. On this basis, we evaluated the antioxidant potential, and determined the total phenolic and flavonoid contents of the e thanol e xtract of the s tem bark of A nogeissus l eiocarpus [ EESAL ]. Antioxidant assays carried out include: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, phosphomolybdate, β-carotene bleaching, ferric reducing, and hydroxyl radical scavenging activities. Results of DPPH assay showed no significant difference ( p antioxidant capacity of 190.00 ± 70.53 µg butylated hydroxytoluene equivalents [BHTE]/mg dry extract, while β-carotene bleaching assay gave percent antioxidant activities of both EESAL and BHT as 81.46±1.62 and 80.90±1.39 respectively. Ferric reducing abilities of both EESAL and ascorbic acid increased in a concentration-dependent manner with EESAL displaying a significantly ( p concentration with no significant difference at the highest concentration. Total phenolic and flavonoid contents of EESAL were obtained as 608.10 ± 2.12 µg GAE/mg and 78.96 ± 3.37 µg QE/mg respectively. Taken together, the free radical scavenging and antioxidant activity of EESAL is likely due to its high phenolic content with complementary effects of the flavonoid components.

Total and corrected antioxidant capacity in hemodialyzed patients

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Margioris Andrew N

2003-07-01

Full Text Available Abstract Background Oxidative stress may play a critical role in the vascular disease of end stage renal failure and hemodialysis patients. Studies, analyzing either discrete analytes and antioxidant substances, or the integrated total antioxidant activity of human plasma during hemodialysis, give contradictory results. Methods Recently, we have introduced a new automated method for the determination of Total Antioxidant Capacity (TAC of human plasma. We have serially measured TAC and corrected TAC (cTAC: after subtraction of the interactions due to endogenous uric acid, bilirubin and albumin in 10 patients before the onset of the dialysis session, 10 min, 30 min, 1 h, 2 h and 3 h into the procedure and after completion of the session. Results Our results indicate that TAC decreases, reaching minimum levels at 2 h. However, corrected TAC increases with t1/2 of about 30 min. We then repeated the measurements in 65 patients undergoing dialysis with different filters (36 patients with ethylene vinyl alcohol copolymer resin filter -Eval-, 23 patients with two polysulfone filters -10 with F6 and 13 with PSN140-, and 6 patients with hemophan filters. Three specimens were collected (0, 30, 240 min. The results of this second group confirm our initial results, while no significant difference was observed using either filter. Conclusions Our results are discussed under the point of view of possible mechanisms of modification of endogenous antioxidants, and the interaction of lipid- and water-soluble antioxidants.

In vitro antioxidant and free radical scavenging activity of Leonurus ...

African Journals Online (AJOL)

The total phenolic compounds in the extracts were determined as gallic acid equivalents, and total flavonoid contents were calculated as quercetin equivalents from a calibration curve. Keywords: Antioxidant activity, Fe2+ chelating, 1,1-diphenyl-2-picryl hydrazyl (DPPH), phenol, Leonurus cardiaca, Grammosciadium ...

A new automated method for the determination of the Total Antioxidant Capacity (TAC of human plasma, based on the crocin bleaching assay

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Notas George

2002-08-01

Full Text Available Abstract Background Antioxidant molecules, which scavenge free radical species to prevent or delay oxidative damage of important macromolecules, membrane lipids and lipoproteins, are prevalent in plasma and other biological fluids. Among them, bilirubin, uric acid and protein thiols are the major endogenous antioxidants, while vitamins C and E, as well as a number of food-derived (polyaromatic substances, belonging to stilbens, flavonoids and phenolic acids, are the main classes of nutritional antioxidants. Assays for total antioxidant capacity in plasma differ in their type of oxidation source, target and measurement used to detect the oxidized product. Methods In the present work we present an automated assay for the estimation of blood total antioxidant capacity (TAC assay, based on the crocin bleaching (oxidation method. This method was adapted on a modern autoanalyzer, was linear over a wide range of values (0–3 mmol/L, and performed using an end point measurement. Results The TAC method presented a linear correlation with another automated commercial Total Antioxidant Status (TAS test. Detection of the interference of different metabolites revealed a significant participation of TAC from uric acid, bilirubin, albumin, a minor interference from ascorbic acid, and no interference from hemoglobin. TAC was not modified by two freeze/thawing cycles, and was stable in samples stored at room temperature for 4 hours. K-EDTA and heparin were the best anticoagulants, while citrate decreased TAC by 20%. Reference values derived from samples of normal blood donors was 1.175 ± 0.007 mmol/L (mean ± SEM, while a diet rich in antioxidants more than doubled this value. Conclusions The proposed TAC assay, is fully automated, stable and reliable, and could be of value in the estimation of the AC of plasma. It is further proposed to calculate the antioxidant capacity of plasma after a subtraction of all interference deriving from endogenous and

Mineral Composition, Total Phenol Content and Antioxidant Activity of a Macrolichen Everniastrum cirrhatum (Fr. Hale (Parmeliaceae

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T. R. Prashith Kekuda

2011-01-01

Full Text Available In the present study, we investigated for the first time mineral composition, total phenol content and antioxidant activity of a foliose macrolichen Everniastrum cirrhatum (Fr. Hale (Parmeliaceae from Bhadra wildlife sanctuary, Karnataka, India. Mineral content of the lichen was estimated by Atomic absorption spectrophotometer after acid digestion. The secondary metabolites were detected by thin layer chromatography (TLC and phytochemical assays. The lichen material was extracted with methanol in soxhlet apparatus. Total phenol content was estimated by folin ciocalteu method. Antioxidant activity was determined by DPPH, Ferric reducing and metal chelating assays. Among the principal elements, calcium was found in high concentration followed by magnesium, potassium and phosphorus. Among trace elements, iron was detected in high amount followed by zinc, manganese and copper. The DPPH radical scavenging activity was found to be dose dependent with an IC50 of 6.73 μg/mL. In ferric reducing assay, the absorbance increased with the concentration of extract suggesting reducing power. The extract exhibited good metal chelating activity with an IC50 value of 29.28 μg/mL. Total phenol content was 101.2 mg tannic acid equivalents per gram of extract. Phytochemical analysis revealed the presence of alkaloids, saponins, tannins and terpenoids. TLC revealed atranorin, salazinic acid and protolichesterinic acid. The lichen can be consumed as a source of minerals required for the body as appreciable amount of minerals has been detected. The marked antioxidant activity may be attributed to the presence of phenol content in the extract. Further studies on isolation of metabolites and their bioactivities are under investigation.

Development and validation of a simple high performance thin layer chromatography method combined with direct 1,1-diphenyl-2-picrylhydrazyl assay to quantify free radical scavenging activity in wine.

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Agatonovic-Kustrin, Snezana; Morton, David W; Yusof, Ahmad P

2016-04-15

The aim of this study was to: (a) develop a simple, high performance thin layer chromatographic (HPTLC) method combined with direct 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay to rapidly assess and compare free radical scavenging activity or anti-oxidant activity for major classes of polyphenolics present in wines; and (b) to investigate relationship between free radical scavenging activity to the total polyphenolic content (TPC) and total antioxidant capacity (TAC) in the wine samples. The most potent free radical scavengers that we tested for in the wine samples were found to be resveratrol (polyphenolic non-flavonoid) and rutin (flavonoid), while polyphenolic acids (caffeic acid and gallic acid) although present in all wine samples were found to be less potent free radical scavengers. Therefore, the total antioxidant capacity was mostly affected by the presence of resveratrol and rutin, while total polyphenolic content was mostly influenced by the presence of the less potent free radical scavengers gallic and caffeic acids. Copyright © 2015 Elsevier Ltd. All rights reserved.

Antioxidant capacity and physical exercise

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A Marciniak

2009-09-01

Full Text Available The aim of this article is a presentation of current knowledge regarding the changes of plasma antioxidant capacity observed in response to physical exercise. Human body created the enzymatic and non-enzymatic systems, which play a protective role in the harmful impact of free radicals. Those two systems constitute what is known as the plasma total antioxidant capacity. The amount of reactive oxygen species (ROS and reactive nitrogen species (NOS in combination with oxidation processes increases in some tissues during physiological response to physical exercise. These changes are observed after single bout of exercise as well as after regular training. The response of human body to physical exercise can be analysed using various models of exercise test. Application of repeated type of exhaustion allows for characterizing the ability of human body to adjust to the increased energy loss and increased oxygen consumption. This article presents the characteristics of components of plasma antioxidant capacity, the mechanisms of free radicals production and their role in human body. It discusses also the currently used methods of detecting changes in total antioxidant capacity and its individual elements in response to single bout of exercise and regular training. It presents the review of literature about research performed in groups of both regularly training and low exercise activity individuals as well as in group of healthy subjects and patients with circulation diseases.

Antioxidant enzymes activities in obese Tunisian children

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Sfar Sonia

2013-01-01

Full Text Available Abstract Background The oxidant stress, expected to increase in obese adults, has an important role in the pathogenesis of many diseases. It results when free radical formation is greatly increased or protective antioxidant mechanisms are compromised. The main objective of this study is to evaluate the antioxidant response to obesity-related stress in healthy children. Methods A hundred and six healthy children (54 obese and 52 controls, aged 6–12 years old, participated in this study. The collected data included anthropometric measures, blood pressure, fasting glucose, total cholesterol, triglycerides and enzymatic antioxidants (Superoxide dismutase: SOD, Catalase: CAT and Glutathione peroxidase: GPx. Results The first step antioxidant response, estimated by the SOD activity, was significantly higher in obese children compared with normal-weight controls (p  Conclusions The obesity-related increase of the oxidant stress can be observed even in the childhood period. In addition to the complications of an increased BMI, obesity itself can be considered as an independent risk factor of free radical production resulting in an increased antioxidant response.

Free radical scavenging activity and lipid peroxidation inhibition of Hypericum helianthemoides (spach Boiss

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Soheila Moein

2015-06-01

Full Text Available Antioxidants are compounds that obstruct the oxidation of macromolecules in the body. In general, there are two categories of antioxidants, natural and synthetic. Recently, interest has been increased considerably for obtaining new natural antioxidants. In this study, the scavenging of free radicals such as DPPH, NO and OH by Hypericum helianthemoides extract was evaluated. Also, the antioxidant properties of this extract were evaluated by FRAP, FTC methods and determination phenolic compounds. The plant was collected from north of Fars Province and plant extraction was obtained using ethanol. In DPPH radical scavenging, different concentrations of the Hypericum extract were added to DPPH radical. In hydroxyl radical scavenging, Fenton reaction mixture, TCA and TBA were mixed with Hypericum extract. In nitric radical scavenging, nitropruside was mixed with Hypericum extract and then sulphanilic acid, naphthylene diamine were added. In determination of phenolic compounds, Folin-ciocalteu and sodium carbonate were added to Hypericum extract. In DPPH radical scavenging, the IC50 of Hypericum extract (309.35±6.5μg/ml was higher than the antioxidant standards, BHT (IC50=81.9±2.6 μg/ml and quercetin (IC50=60.04±6.48 μg/ml. The highest scavenging of hydroxyl radicals was observed in Hypericum extract (70.3±0.8%, 125 μg/ml. In gallic acid it was (73.8±3.3%. In 200 μg/ml of Hypericum extract scavenged NO radical (85.2±2.7%. In FRAP method, the IC50 of this extract was 109.7±10.5 μg/ml. In FTC method, the inhibition of lipid peroxidation by Hypericum extract, BHT and ascorbic acid were 59.2±2.2, 66.9±0.15, 64.06±0.02 respectively. Total phenol of the plant extract was 3±0.4 mg/g.

Antioxidant capacities and total phenolic contents of 20 polyherbal remedies used as tonics by folk healers in Phatthalung and Songkhla provinces, Thailand.

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Chanthasri, Wipawee; Puangkeaw, Nuntitporn; Kunworarath, Nongluk; Jaisamut, Patcharawalai; Limsuwan, Surasak; Maneenoon, Katesarin; Choochana, Piyapong; Chusri, Sasitorn

2018-02-21

Uses of polyherbal formulations have played a major role in traditional medicine. The present study is focused on the formulations used in traditional Thai folkloric medicine as tonics or bracers. Twenty documented polyherbal mixtures, used as nourishing tonics by the folk healers in Phatthalung and Songkhla provinces in southern Thailand, are targeted. Despite traditional health claims, there is no scientific evidence to support the utilization of polyherbal formulations. The phenolic and flavonoid contents of the polyherbal formulations and a series of antioxidant tests were applied to measure their capability as preventive or chain-breaking antioxidants. In addition, the cytotoxic activity of effective formulations was assayed in Vero cells. Ninety-eight plant species belonging to 45 families were used to prepare the tested formulation. The preliminary results revealed that water extracts of THP-R016 and THP-R019 contain a high level of total phenolic and flavonoid contents and exhibit remarkable antioxidant activities, as tested by DPPH, ABTS, and FRAP assays. The extract of THP-R019 also showed the strongest metal chelating activities, whereas THP-R016 extract possessed notable superoxide anion and peroxyl radical scavenging abilities. The data provide evidence that the water extracts of folkloric polyherbal formulations, particularly THP-R016, are a potential source of natural antioxidants, which will be valuable in the pharmaceutical and nutraceutical industries. The free radical scavenging of THP-R016 may be due to the contribution of phenolic and flavonoid contents. Useful characteristics for the consumer, such as the phytochemical profiles of active ingredients, cellular based antioxidant properties and beneficial effects in vivo, are under further investigation.

In Vitro Antioxidant-Activity Evaluation of Gallic-Acid-Grafted Chitosan Conjugate Synthesized by Free-Radical-Induced Grafting Method.

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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.

Assessment of total flavonoid content and antioxidant activity of Mullein (Verbascum songaricum ecotypes

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2017-11-01

Full Text Available Background and objectives: The Mullein genus is the largest genus of Scrophulariaceae family which has extensive natural habitat in southwest of Iran. Mullein contains compounds such as phenolic compounds, mucilage, saponins and anthocyanin. The aim of this study was to evaluate the total flavonoid content and antioxidant activity of mullein ecotypes in Iran. Methods: Six ecotypes of the Verbascum songaricum were evaluated. Determination of total flavonoid content was performed bythealuminium chloride colourimetric method. The antioxidant activity of the flower extracts was measured using the DPPH method. Results: The results showed that total flavonoid content and antioxidant activity were different among ecotypes.  The highest and lowest amounts of total flavonoidwas obtained  from Shermard ecotype (13.42 mg rutin /g DW and Klar ecotypes(10.10 mg rutin /g DW, respectively. The highest amounts of antioxidant activity were obtained from the Shermard ecotype (IC50 246.35 μg/mL. The correlation analysis showed that a significant relation between flavonoid, antioxidant activity and habitat elevation. Conclusion: Total flavonoid content and antioxidant activity of the samples were affected by habitat climatic.  The present data indicated that the highest antioxidant activity may be due to higher flavonoid content and the habitat elevation was effective on the flavonoid content. Due to the high amounts of flavonoid and antioxidant activity of mullein extract, it seems to be a good herbal option as an antioxidant in complementary therapies.

Contents of constituents and antioxidant activity of seed and pulp extracts of Annona coriacea and Annona sylvatica

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RSR. Benites

Full Text Available AbstractThe antioxidant potential of fruit pulp and seeds of extracts of the Annona coriacea, and A. sylvatica(Annonaceae were investigated, as well contents total phenolics, flavonoids, condensed tannins and ascorbic acid. Was used to determine the antioxidant activity the 1,1-diphenyl-1-picrylhydrazyl free radical (DPPH, β-carotene bleaching and ABTS radical cation method. The total phenol, total flavonoid, condensed tannin, and ascorbic acid contents were measured spectrophotometrically. In this study, the pulp and seeds of the fruits were extracted using methanol/water (8:2 for maceration. The seed extracts of A. coriacea demonstrated a moderate antioxidant effect with free radical scavenging activity of 31.53%, by the DPPH test, 51.59% by the β-carotene bleaching test and 159.50 µM trolx/g of extract in the ABTS assay. We found that the hydromethanolic seed extract of A. coriacea had high total phenol (147.08 ± 4.20 mg of GAE/g of extract and flavonoid (131.18 ± 2.31 mg of QE/g of extract content. This indicated that the antioxidant activity of the extracts was related to the contents of these constituents.

Antioxidant Activity of Phyllanthus niruri Extract, Rutin and Quercetin

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Djaja Rusmana

2017-08-01

Full Text Available BACKGROUND: Normal metabolism of oxygen and exogenous factors constantly generate free radicals which could be harmful to the human body. Human need antioxidants to provide protection against free radicals, thus plants are a good source of natural antioxidants. Phyllanthus niruri (P. niruri has been known to possess several medicinal properties and contain numerous active phytochemical. In this research, we conducted phytochemical screening and antioxidant assay of P. niruri extract along with the compounds rutin and quercetin, which are flavonoids possessing medicinal properties. This study was conducted to determine P. niruri, rutin and quercetin as antioxidant. METHODS: In this study, qualitative phytochemical screening was performed to detect phenol, flavonoid, saponin, tannin, steroid/triterpenoid, terpenoid and alkaloid in P. niruri extract. Antioxidant analysis of P. niruri, rutin and quercetin was conducted using total measured phenolic content, 2,2-diphenyl-1-picrylhydrazil (DPPH, 2,2’-azinobis-3-ethylbenzo-thiazoline-6-sulfonic acid (ABTS and ferric reducing antioxidant power (FRAP assays. RESULTS:  The study revealed that P. niruri extract contained saponin, phenol, flavonoid and tannin based on phytochemical screening. In DPPH and ABTS assays quercetin possessed highest antioxidant activity with IC50 value of 0.55 and 1.17 μg/ml respectively. Meanwhile, P. niruri extract showed the highest FRAP activity which was 373.95 μM Fe(II/μg extract. Rutin possessed the lowest antioxidant activity in all antioxidant assays. CONCLUSION: This study confirmed that P. niruri extract and quercetin have great potential as a natural antioxidant source. KEYWORDS: asntioxidant, phytochemical, Phyllanthus niruri, quercetin, rutin, free radical

Isoflavone content and antioxidant properties of soybean seeds

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Edina Šertović

2011-01-01

Full Text Available The isoflavone content and antioxidant properties of five Croatian soybean seed cultivars from two locations were analysed. The content of total and individual isofavones was determined by high performance liquid chromatography. For determination of antioxidant properties scavenging capacity on DPPHֹ radicals has been applied. The total phenolic content, oil and protein content in soybean cultivars were also determined. Significant differences in the content of individual isoflavones were observed within the soybean cultivars. The total phenol content in soybean cultivars ranged from 87.2 to 216.3 mg GAE/100g of soybean. The total isoflavone content in soybean seeds ranged from 80.7 to 213.6 mg/100g of soybean. The most abundant isoflavone in soybean seeds was genistein. There was statistically significant difference (p < 0.05 among two locations in total and individual isoflavone contents. The highest contents of total isoflavones were found in cultivar “os55-95”. Conversely, cultivars poor in isoflavones also showed low levels of DPPH-radical scavenging activity.

Total phenolics and antioxidant activity of five medicinal plant

International Nuclear Information System (INIS)

Sousa, Cleyton Marcos de M.; Silva, Hilris Rocha e; Vieira-Junior, Gerardo Magela; Ayres, Mariane Cruz C.; Costa, Charllyton Luis S. da; Araajo, Delton Servulo; Cavalcante, Luis Carlos D.; Barros, Elcio Daniel S.; Araujo, Paulo Breitner de M.; Brandao, Marcela S.; Chaves, Mariana H.

2007-01-01

This paper describes total phenolics content and antioxidant activity in the ethanolic extract of leaves, bark and roots of five medicinal plants: Terminalia brasiliensis Camb., Terminalia fagifolia Mart. and Zucc., Copernicia cerifera (Miller) H.E. Moore, Cenostigma macrophyllum Tul. var. acuminata Teles Freire and Qualea grandiflora Mart. The total phenolics content of the plant extracts, determined by the Folin-Ciocalteu method, varied from 250.0 ±8,2 to 763,63 ±13.03 mg of gallic acid equivalent/g dry EtOH extract. The antioxidant activity of extracts was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay system. Extract of bark from T. brasiliensis, the most active, with an EC 50 value of 27.59 ± 0.82 μg/mL, was comparable to rutin (EC 50 = 27.80 ± 1.38) and gallic acid (EC 50 = 24.27 ± 0.31), used as positive controls. The relationship between total phenolic content and antioxidant activity was positive and significant for T. brasiliensis, C. macrophyllum and C. cerifera. (author)

Decrease of total antioxidant capacity during coronary artery bypass surgery.

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Kunt, Alper Sami; Selek, Sahbettin; Celik, Hakim; Demir, Deniz; Erel, Ozcan; Andac, Mehmet Halit

2006-09-01

Cardiac surgery induces an oxidative stress, which may lead to impairment of cardiac function. In this study, we aimed to measure the changes of oxidative and antioxidative status of patients undergoing coronary artery bypass surgery (CABG). We studied 79 patients who underwent CABG with and without cardiopulmonary bypass (CPB). Of the 79 patients, 39 had CPB and 40 did not. Blood samples were drawn before, during, and after the surgery. Antioxidant status was evaluated by measuring total antioxidant capacity (TAC), and oxidative status was evaluated by measuring total peroxide (TP) levels and oxidative stress index (OSI). TP and OSI levels increased, while TAC decreased progressively after the beginning of surgery, for all patients. There were negative correlations between TAC levels and aortic cross-clamping period and anastomosis time ( r = -0.553, p antioxidant vitamins such as vitamins C and E may be beneficial for patients undergoing CABG.

Free Radical Scavenging Properties of Annona squamosa

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Vikas, Biba; Akhil B, S; P, Remani; Sujathan, K

2017-10-26

Annona squamosa has extensively been used in the traditional and folkloric medicine and found to possess many biological activities. Different solvents, petroleum ether, chloroform, ethyl acetate and methanol extracts of Annona squamosa seeds (ASPE, ASCH, ASEA, ASME) have been used to prepare plant extracts. The present investigations dealt with the free radical scavenging activity of four extracts using various techniques such as total reducing power estimation, total phenolic count, 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging effect, evaluation of ABTS cation decolorisation capacity, FRAP assay, hdroxyl radical scavenging assay, super oxide assay and Nitric oxide radical scavenging assay of the extracts. The results showed that the four extracts of Annona squamosa showed significant reducing power in four extracts. The total phenolic contents in petroleum ether, chloroform, ethyl acetate, methanol extracts and positive control were 0.64±0.17, 0.54±0.27, 0.49±0.24, 0.57±0.22 and 0.66±0.33. The antioxidant capacity by ABTS assay of ASPE, ASCH, ASEA, ASME and positive control, trolox showed 77.75±0.5,73.25±1.7,78.5± 1.2 , 80 ± 0.8 μg/ml and 94.2 ± 0.9 respectively. The (50 % scavenging activity) SA50 of ASPE and ASCH, ASEA and ASME was found to be 34.4 μg/ml, 43.8 μg/ml 34.7 μg/m and 28.8 μg/ml respectively by DPPH assay. The percentage of hydroxyl radical scavenging increased with the increasing concentration of the extracts. ASPE, ASCH, ASEA and ASME showed superoxide radical scavenging activity, as indicated by their values 66 ± 0.5, 68 ± 1 ,63 ± 1 and 70 ± 0.5 μg/ml respectively compared to gallic acid which was 97 ± 0.5 μg/ml. The values for scavenging of nitric oxide for ASPE, ASCH, ASEA and ASME were 91.0 ± 1.0, 66.75 ± 0.5, 71.75 ± 1.1 and 75.75 ± 1.15 μg/ml while value for standard ascorbic acid was 91.0 ± 1.0 μg/ml. The results revealed strong antioxidants in four extracts may lead to the development of potent

Metal-Diazo Radicals of α-Carbonyl Diazomethanes

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Li, Feifei; Xiao, Longqiang; Liu, Lijian

2016-03-01

Metal-diazo radicals of α-carbonyl diazomethanes are new members of the radical family and are precursors to metal-carbene radicals. Herein, using electron paramagnetic resonance spectroscopy with spin-trapping, we detect diazo radicals of α-carbonyl diazomethanes, induced by [RhICl(cod)]2, [CoII(por)] and PdCl2, at room temperature. The unique quintet signal of the Rh-diazo radical was observed in measurements of α-carbonyl diazomethane adducts of [RhICl(cod)]2 in the presence of 5,5-dimethyl-pyrroline-1-N-oxide (DMPO). DFT calculations indicated that 97.2% of spin density is localized on the diazo moiety. Co- and Pd-diazo radicals are EPR silent but were captured by DMPO to form spin adducts of DMPO-N• (triplet-of-sextets signal). The spin-trapping also provides a powerful tool for detection of metal-carbene radicals, as evidenced by the DMPO-trapped carbene radicals (DMPO-C•, sextet signal) and 2-methyl-2-nitrosopropane-carbene adducts (MNP-C•, doublet-of-triplets signal). The transformation of α-carbonyl diazomethanes to metal-carbene radicals was confirmed to be a two-step process via metal-diazo radicals.

Spectroscopic studies on the antioxidant activity of p-coumaric acid

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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.

Antioxidants Potential of the Filamentous Fungi (Mucor circinelloides).

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Hameed, Ahsan; Hussain, Syed Ammar; Yang, Junhuan; Ijaz, Muhammad Umair; Liu, Qing; Suleria, Hafiz Ansar Rasul; Song, Yuanda

2017-10-07

Three important strains of Mucor circinelloides grown in complete and minimal media for specified period (72 h, 120 h and 168 h) under submerged fermentation conditions were investigated for their potential antioxidants/secondary metabolite production. All mycelial extracts demonstrated effective antioxidant activities in terms of β-carotene/linoleic acid bleaching, radical scavenging, reduction of metal ions and chelating abilities against ferrous ions. Different extraction methods and solvent systems affected the recovery yield and antioxidant activities of the extracts significantly ( p ≤ 0.05). Ethanolic extracts were found to be rich source of antioxidant components and subsequently more effective in antioxidant properties. Fermentation period and media used also significantly affected ( p ≤ 0.05) the antioxidant production and the resulting antioxidant properties. The (ethanolic) extracts of all the strains from late exponential growth phase (120 h) showed highest antioxidant production with topmost reducing, chelating and radical scavenging capabilities. Strain MC277.49 was found to be the highest producer of antioxidants followed by MC108.16 and WJ11. Phenolic compounds were detected significantly in higher ( p ≤ 0.05) amount succeeded by the condensed tannins and flavonoids. Total phenol content of each extract was attributed to overall antioxidant capacity. Submerged fermentation with nutritional stress conditions were found to be excellent way of producing surplus amount of natural antioxidants/secondary metabolites with their vast potential commercial application in food and pharmaceutical industries.

α-Tocopherol impact on oxy-radical induced free radical decomposition of DMSO: Spin trapping EPR and theoretical studies

International Nuclear Information System (INIS)

Jerzykiewicz, Maria; Cwielag-Piasecka, Irmina; Witwicki, Maciej; Jezierski, Adam

2011-01-01

Graphical abstract: α-Tocopherol inhibits the oxidation of ·CH 3 to ·OCH 3 . Display Omitted Highlights: → α-Tocopherol does not inhibit the oxidation of DMSO to ·CH 3 . → α-Tocopherol inhibits the oxidation of ·CH 3 to ·OCH 3 . → α-Tocopherol does not inhibit the oxidation of PBN. → The structures of observed spin adducts were theoretically confirmed. - Abstract: EPR spin trapping and theoretical methods such as density functional theory (DFT) as well as combined DFT and quadratic configuration interaction approach (DFT/QCISD) were used to identify the radicals produced in the reaction of oxy-radicals and dimethyl sulfoxide (DMSO) in the presence and absence of α-tocopherol. Additionally, the mixtures of α-tocopherol with linolenic acid and glyceryl trilinoleate as well as bioglycerols (glycerol fractions from biodiesel production) were tested. α-Tocopherol inhibited oxidation of the main decomposition product of DMSO, ·CH 3 to ·OCH 3 but did not prevent the transformation process of N-t-butyl-α-phenylnitrone (PBN) into 2-methyl-2-nitrosopropane (MNP). Theoretical investigations confirmed the structures of proposed spin adducts and allowed to correlate the EPR parameters observed in the experiment with the spin adducts electronic structure.

Free radical attack on membrane lipid and antioxidant vitamins in the course of pre-eclamptic pregnancy.

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Atiba, Adeniran S; Abbiyesuku, Fayeofori M; 'Niran-atiba, Temitope A; Oparinde, Dolapo P; Ajose, Olabamiji A; Akindele, Rasaq A

2014-01-01

Despite the volume of knowledge and daily reports on pre-eclampsia, its pathogenesis is still yet to be ascertained. Oxidative stress (oxidant (free radical) in excess of antioxidant) injury is one of the recently suggested pathogenetic mechanisms. This study, however, was designed to determine second and third trimesters of plasma malondialdehyde (product of free radical attack on membrane lipid) and vitamins C and E in pre-eclamptic Nigerian women. A Total of 100 subjects, each for pre-eclamptic, apparently normal and non-pregnant women qualified for the study. Venous blood samples were taken in the second and third trimesters of pregnancy and at the point of contact for non-pregnant women. Variables were analyzed using SPSS version 16, taking level of significance to be 0.05. Plasma malondialdehyde in the third trimester of normal pregnancy (2.03±0.71µmol/l) was found to be significantly higher than the one in the second trimester (1.65±0.62µmol/l) (pvitamin C values for subjects with normal pregnancy were similar in the second and third trimesters (38.25±19.66 vs. 38.66±19.40; p=0.882). For subjects with pre-eclampsia, the mean Vit C values were also similar in the 2(nd) and 3(rd) trimesters (35.05±18.37 vs. 37.20±24.44µmol/l; p=0.175). Mean vitamin E values in the second and third trimesters were also similar for subjects with normal pregnancy (28.62±13.85 vs. 28.50±13.35µmol/l; p=0.950). A similar finding was observed in pre-eclamptic subjects (25.09±12.79 vs. 28.00±14.83µmol/l; p=0.067). There was an increased product of membrane lipid attack (malondialdehyde) with no change in plasma levels of vitamins C and E as pregnancy advances into the third trimester of both normal and pre-eclamptic pregnancies. Antioxidant vitamins may not be useful in stopping the progression of free radical attack on membrane lipid to control pre-eclampsia.

EPR detection of hydroxyl radical generation and its interaction with antioxidant system in Carassius auratus exposed to pentachlorophenol

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Luo Yi [Key Laboratory of Pollution Processes and Environmental Criteria (Nankai University), Ministry of Education, College of Environmental Sciences and Engineering, Nankai University, Tianjin 300071 (China); Wang Xiaorong, E-mail: yiyluo@gmail.com [State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University, Nanjing 210093 (China); Ji Liangliang; Su Yan [State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University, Nanjing 210093 (China)

2009-11-15

In the present study, direct evidence of hydroxyl radical production in livers of Carassius auratus exposed to pentachlorophenol (PCP) was provided using electron paramagnetic resonance (EPR) with spin-trapping. A dose-effect relationship was obtained between hydroxyl radical intensities and PCP exposure. It was observed that hydroxyl radical was significantly induced by 0.001 mg l{sup -1} (below the criteria for Chinese fishery water quality) of PCP exposure. A strong positive correlation (r = 0.9581, p < 0.001) was observed between PCP liver concentrations and hydroxyl radical intensities within 7 d of PCP exposure, which suggests that hydroxyl radical are mainly produced from PCP itself. However, no correlation was observed between PCP liver concentrations and hydroxyl radical intensities after 7 d, and a higher intensity of hydroxyl radical could still be observed when the PCP liver concentrations decreased to a lower level, which suggests that other mechanisms may possibly contribute to hydroxyl radical production after 7 d. The glutathione/oxidized glutathione (GSH/GSSG) ratio decreased below that of the control level during the entire period of PCP exposure (0.05 mg l{sup -1}), which suggested oxidative stress occurred.

Effect of radiation processing on the antioxidant activity of Sage and Cinnamon

International Nuclear Information System (INIS)

El-Niley, H. F. G.; Farag, M. D. H.

2012-12-01

In the present study, the effect of radiation processing on dried sage leaves and cinnamon barks samples were carried out at dose level of 25 kGy. Total phenolic content was determined in the extracts of these herbs alongside the antioxidant properties of their methanoic extracts were assessed using reducing power assay and by DPPH radical test within an extract concentration range 2.5 to 40 mg/ml of methanol. The result showed the total phenolic compounds were increased by 11.18% and 10.19% for irradiated sage and cinnamon, respectively. The values of EC 50 estimated from the results of reducing power assay and DPPH radical test showed the sage extracts had higher antioxidant activity tham cinnamon extracts. In summary, gamma- irradiation of dried sage leaves and cinnamon barks was found to be significantly increase the antioxidant properties of dried sage leaves and cinnamon barks but also enhanced the antioxidant properties, to some extent. (Author)

The Role of Electron Transport and Trapping in MOS Total-Dose Modeling

International Nuclear Information System (INIS)

Flament, O.; Fleetwood, D.M.; Leray, J.L.; Paillet, P.; Riewe, L.C.; Winokur, P.S.

1999-01-01

Deep and shallow electron traps form in irradiated thermal SiO 2 as a natural response to hole transport and trapping. The density and stability of these defects are discussed, as are their implications for total-dose modeling

The Antioxidant Activity of Quercetin in Water Solution

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Riccardo Amorati

2017-06-01

Full Text Available Abstract: Despite its importance, little is known about the absolute performance and the mechanism for quercetin’s antioxidant activity in water solution. We have investigated this aspect by combining differential oxygen-uptake kinetic measurements and B3LYP/6311+g (d,p calculations. At pH = 2.1 (30 °C, quercetin had modest activity (kinh = 4.0 × 103 M−1 s−1, superimposable to catechol. On raising the pH to 7.4, reactivity was boosted 40-fold, trapping two peroxyl radicals in the chromen-4-one core and two in the catechol with kinh of 1.6 × 105 and 7.0 × 104 M−1 s−1. Reaction occurs from the equilibrating mono-anions in positions 4′ and 7 and involves firstly the OH in position 3, having bond dissociation enthalpies of 75.0 and 78.7 kcal/mol, respectively, for the two anions. Reaction proceeds by a combination of proton-coupled electron-transfer mechanisms: electron–proton transfer (EPT and sequential proton loss electron transfer (SPLET. Our results help rationalize quercetin’s reactivity with peroxyl radicals and its importance under biomimetic settings, to act as a nutritional antioxidant.

Antioxidant, antibacterial activity, and phytochemical characterization of Melaleuca cajuputi extract.

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Al-Abd, Nazeh M; Mohamed Nor, Zurainee; Mansor, Marzida; Azhar, Fadzly; Hasan, M S; Kassim, Mustafa

2015-10-24

The threat posed by drug-resistant pathogens has resulted in the increasing momentum in research and development for effective alternative medications. The antioxidant and antibacterial properties of phytochemical extracts makes them attractive alternative complementary medicines. Therefore, this study evaluated the phytochemical constituents of Melaleuca cajuputi flower and leaf (GF and GL, respectively) extracts and their antioxidant and antibacterial activities. Radical scavenging capacity of the extracts was estimated using 2,2-diphenyl-2-picrylhydrazyl and Fe(2+)-chelating activity. Total antioxidant activity was determined using ferric reducing antioxidant power assay. Well diffusion, minimum inhibitory concentration, and minimum bactericidal concentration assays were used to determine antibacterial activity against eight pathogens, namely Staphylococcus aureus, Escherichia coli, Bacillus cereus, Staphylococcus epidermidis, Salmonella typhimurium, Klebsiella pneumonia, Streptococcus pneumoniae, and Pasteurella multocida. We identified and quantified the phytochemical constituents in methanol extracts using liquid chromatography/mass spectrometry (LC/MS) and gas chromatography (GC)/MS. This study reports the antioxidant and radical scavenging activity of M. cajuputi methanolic extracts. The GF extract showed better efficacy than that of the GL extract. The total phenolic contents were higher in the flower extract than they were in the leaf extract (0.55 ± 0.05 and 0.37 ± 0.05 gallic acid equivalent per mg extract dry weight, respectively). As expected, the percentage radical inhibition by GF was higher than that by the GL extract (81 and 75 %, respectively). A similar trend was observed in Fe(2+)-chelating activity and β-carotene bleaching tests. The antibacterial assay of the extracts revealed no inhibition zones with the Gram-negative bacteria tested. However, the extracts demonstrated activity against B. cereus, S. aureus, and S. epidermidis. In

Effect of concentration temperature on some bioactive compounds and antioxidant proprieties of date syrup.

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Abbès, Fatma; Besbes, Souhail; Brahim, Bchir; Kchaou, Wissal; Attia, Hamadi; Blecker, Christophe

2013-08-01

The effect of the concentration temperature on the antioxidant activity, carotenoid and phenolic compounds of date syrup was investigated. Date juice was concentrated at 100  and at "60  in vacuum". After concentration, total phenolic, tannin, non-tannin, flavonoid and carotenoid content were determined spectrophotometrically and high-performance liquid chromatography was used for determination of 5-Hydroxymethyl-2-furfuraldehyde content. The antioxidant activity of date syrup was evaluated by various antioxidant methods including total antioxidant, 2,2-diphenyl-1-picrylhydrazyl free radical scavenging test, ferric reducing antioxidant power and β-carotene bleaching. All date syrups showed strong antioxidant activity accompanied by high total phenolic contents. Results showed that concentration at 100  significantly enhanced the antioxidant activities and total phenolic contents of date syrups compared to vacuum concentration at 60 . A good correlation between the antioxidant activity and total phenolic content and flavonoid was observed.

Effect of hemodialysis on total antioxidant status of chronic renal ...

African Journals Online (AJOL)

Background: Renal failure is accompanied by oxidative stress, which is caused by enhanced production of reactive oxygen species and impaired antioxidant defense. Aim: To assess the effect of hemodialysis (by cellulose membrane dialyzer) on plasma total antioxidant status and lipid peroxidation of patients in chronic ...

Evaluation of in-vitro Antioxidant Properties of Hydroalcoholic Solution Extracts Urtica dioica L., Malva neglecta Wallr. and Their Mixture.

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Güder, Aytaç; Korkmaz, Halil

2012-01-01

The study was aimed at evaluating the antioxidant activity of hydroalcoholic solution extracts of Urtica dioica L. (UD), Malva neglecta Wallr. (MN) plants and their mixture. In this study, flower (UDF), root (UDR), seed (UDS) and leaf (UDL) parts of UD and flower (MNF) and leaf (MNL) parts of MN were used. The antioxidant properties of hydroalcoholic extracts and their mixture were evaluated using different antioxidant tests such as total antioxidant activity, reducing power, superoxide anion radical scavenging, hydrogen peroxide scavenging, free radical scavenging, and metal chelating activity for comparison. In addition, total phenolic compounds in the extracts of both plants were determined as catechin equivalent. The various antioxidant activities were compared to natural and synthetic standard antioxidants such as BHA, BHT and α-tocopherol. According to FTC method, the both extracts exhibited strong total antioxidant activity. At the concentration of 100 μg/mL, Hydroalcoholic extracts of UDS, UDR, UDF, UDL, MNF, MNL, and UD-MN showed 81.7%, 79.8%, 78.3%, 76.4%, 77.3%, 74.1%, and 80.7%, respectively. Comparable, 100 μg/mL of standard antioxidants BHA, BHT and α-tocopherol exhibited 66.2%, 70.6%, and 50.1% inhibition on peroxidation of linoleic acid emulsion, respectively. In addition, UD-MN showed strong superoxide anion radical scavenging activity comparable with UDR, UDF, UDL, MNF, and MNL. Based on the findings, plants mixture was commonly found to have synergistically higher antioxidant activity.

Oxidative stress and lowered total antioxidant status are associated with a history of suicide attempts.

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Vargas, Heber Odebrecht; Nunes, Sandra Odebrecht Vargas; Pizzo de Castro, Marcia; Bortolasci, Chiara Cristina; Sabbatini Barbosa, Décio; Kaminami Morimoto, Helena; Venugopal, Kamalesh; Dodd, Seetal; Maes, Michael; Berk, Michael

2013-09-25

There is evidence that depression is accompanied by inflammation, oxidative and nitrosative stress (O&NS) and metabolic disorders. However links between oxidative stress and suicide attempts in depressed patients are poorly understood. This study examines whether a history of suicide attempts is associated with inflammation, O&NS and metabolic disorders. Blood specimens were collected from study participants aged 18-60 (N=342) recruited at the State University of Londrina, Brazil, and measured for oxidative stress biomarkers: nitric oxide metabolites (NOx), lipid hydroperoxides, malondialdehyde, advanced oxidation protein products and plasma total antioxidant potential (TRAP); inflammatory biomarkers: fibrinogen, high-sensitivity C-reactive protein, erythrocyte sedimentation rate, interleukin-6 and tumor necrosis factor-α; and metabolic variables. Subjects were divided into those with (n=141) and without (n=201) a history of suicidal attempts. Individuals with a history of suicide attempts had significantly higher levels of NOx and lipid hydroperoxides and lowered TRAP as compared to individuals without suicide attempts. There were no significant associations between a history of suicide attempts and inflammatory and metabolic biomarkers and metabolic syndrome. Logistic regression showed that both unipolar and bipolar disorder, female gender, smoking behavior and lipid hydroperoxides were significantly associated with a history of suicide attempts. The combined effects of oxidative stress, smoking, depression, female gender were independent from classical risk factors, including marital status, years of education and anxiety. O&NS as well as lowered antioxidant levels may play a role in the pathophysiology of suicidal behavior independently from the effects of depression and smoking, both of which are associated with increased O&NS, and classical suicide predictors, such as years of education and marital status. © 2013 Published by Elsevier B.V.

CYTOTOXIC AND ANTIOXIDANT ACTIVITY OF BUCKWHEAT HULL EXTRACTS

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Martina Danihelová

2013-02-01

Full Text Available Buckwheat contains many prophylactic compounds that are concentrated mainly in outer layers of buckwheat grain. The aim of this study was to prepare buckwheat hull extracts. Ten buckwheat cultivars were screened for their antioxidant and anticancer properties. Total polyphenol content was determined using Folin-Ciocalteau's reagent. Antioxidant activity was established by the method of binding free radical DPPH. Cytotoxic properties were measured on human cervical cancer cells HeLa using mitochondrial cytotoxic test (MTT. Total polyphenol content ranged from 166.67 to 635.31 mg GAE/100 g DW. The highest content displayed tartary buckwheat cultivar Madawaska (0.64% of hulls weight. Among common buckwheat the richest in polyphenols were cultivars Bamby and KASHO-2. The best free radical binding antioxidant activity was found for cultivars with highest polyphenol content. This relationship was not observed for cytotoxic action on human cervical cancer cells. The best growth inhibitory activity on HeLa cancer cells displayed common buckwheat cultivars Bamby and KASHO-2 (up to 50%, extract concentration 100 µg/ml. This was not found for tartary buckwheat cultivar Madawaska.

Investigation of antioxidant activity of some fruit stem barks in the Eastern Black Sea Region

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Aytaç Güder

2016-10-01

Full Text Available Antioxidant compounds in food play an important role as a health protecting factor. Scientific evidence suggests that antioxidants reduce the risk for chronic diseases including cancer and heart disease. Primary sources of naturally occurring antioxidants are whole grains, fruits and vegetables. Antioxidant activity can be investigated by using different methods such as total antioxidant activity, hydrogen peroxide and DPPH free radical scavenging activities, metal-chelating activity, total phenolic and flavonoid contents and others. In this study, antioxidant activity of the ethanol-water extracts of three stem barks, Kiwi (Actinidia chinensis Planch. (AC, lemon (Citrus limon (L. Burm. f. (CL and chery laurel (Laurocerasus officinalis Roem. (LO has been designated. According to FTC method, the total antioxidant activities (% of AC, CL and LO have been determined as 73.35, 67.59 and 61.62, respectively. The DPPH radical scavenging activities of AC, CL, LO, BHA, RUT and TRO in terms of SC50 values (µg/mL were found as 50.52, 56.56, 98.18, 8.58, 17.01, 26.84, respectively. Total phenolic and total flavonoid contents in AC, CL and LO ranged from 850.71 to 457.79 µg gallic acid equivalent/g and 58.77 to 22.91 µg of catechin equivalents/g, respectively. In conclusion, the extracts of AC showed higher antioxidant activity than the other samples so needs further exploration for its effective use in pharmaceutical and medicine sectors.

A Quantum Chemical and Statistical Study of Phenolic Schiff Bases with Antioxidant Activity against DPPH Free Radical

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El Hassane Anouar

2014-04-01

Full Text Available Phenolic Schiff bases are known as powerful antioxidants. To select the electronic, 2D and 3D descriptors responsible for the free radical scavenging ability of a series of 30 phenolic Schiff bases, a set of molecular descriptors were calculated by using B3P86 (Becke’s three parameter hybrid functional with Perdew 86 correlation functional combined with 6-31 + G(d,p basis set (i.e., at the B3P86/6-31 + G(d,p level of theory. The chemometric methods, simple and multiple linear regressions (SLR and MLR, principal component analysis (PCA and hierarchical cluster analysis (HCA were employed to reduce the dimensionality and to investigate the relationship between the calculated descriptors and the antioxidant activity. The results showed that the antioxidant activity mainly depends on the first and second bond dissociation enthalpies of phenolic hydroxyl groups, the dipole moment and the hydrophobicity descriptors. The antioxidant activity is inversely proportional to the main descriptors. The selected descriptors discriminate the Schiff bases into active and inactive antioxidants.

Measurement of the total antioxidant response using a novel automated method in subjects with nonalcoholic steatohepatitis.

Science.gov (United States)

Horoz, Mehmet; Bolukbas, Cengiz; Bolukbas, Fusun F; Sabuncu, Tevfik; Aslan, Mehmet; Sarifakiogullari, Serpil; Gunaydin, Necla; Erel, Ozcan

2005-11-11

Oxidative stress, an increase in oxidants and/or a decrease in antioxidant capacity, is one of the potential biochemical mechanisms involved in the pathogenesis of nonalcoholic steatohepatitis. We aimed to investigate the total antioxidant response using a novel automated method in nonalcoholic steatohepatitis subjects. As a reciprocal measure, we also aimed to determine total peroxide level in the same plasma samples. Twenty-two subjects with biopsy proven nonalcoholic steatohepatitis and 22 healthy controls were enrolled. Total antioxidant response and total peroxide level measurements were done in all participants. The ratio percentage of total peroxide level to total antioxidant response was regarded as oxidative stress index. Total antioxidant response of subjects with nonalcoholic steatohepatitis was significantly lower than controls (p total peroxide level and mean oxidative stress index were higher (all p total peroxide level, total antioxidant response and oxidative stress index (p 0.05). Nonalcoholic steatohepatitis is associated with increased oxidant capacity, especially in the presence of liver fibrosis. The novel automated assay is a reliable and easily applicable method for total plasma antioxidant response measurement in nonalcoholic steatohepatitis.

Ultrasound-Assisted Extraction of Total Flavonoids from Corn Silk and Their Antioxidant Activity

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Ling-Li Zheng

2016-01-01

Full Text Available Object. Ultrasound-assisted extraction of total flavonoids from corn silk and their antioxidant activities were studied. Methods. Response surface methodology was adopted to optimize the extraction conditions and antioxidant activities of the extracted total flavonoids were detected through ferric reducing antioxidant power (FRAP assay. Results. Through a three-level, three-variable Box-Behnken design of response surface methodology (RSM adopting yield as response, the optimal conditions were determined as follows: ultrasonic power 500 W, extraction time 20 min, material solvent ratio 1 : 20, and ethanol concentration 30%. Under the optimum conditions, the extraction yield of total flavonoids was 1.13%. FRAP value of total flavonoids extracted from corn silk was 467.59 μmol/L. Conclusion. The total flavonoids of corn silk could be developed as food natural antioxidant reagents.

Response of total phenolic content and antioxidant activities of bush ...

African Journals Online (AJOL)

The positive health benefits associated with tea are made possible by the antioxidant activity of phenolic compounds present in tea. The total phenolic content and antioxidant activity of bush tea (Athrixia phylicoides DC.) and special tea (Monsonia burkeana) were studied. The extractions were done in triplicate using cold ...

Serum total anti-oxidant capacity of some Nigerian cigarette smokers

African Journals Online (AJOL)

Abstract. Cigarette smoke has been reported to contain free radicals. The interaction of these free radicals with the body defense system and associated health risk among Nigerian smokers have remained scarcely investigated despite the high numbers of smokers in our society. This study thus, investigates the serum total ...

Extraction and antioxidant activities of two species Origanum plant ...

African Journals Online (AJOL)

The antioxidant of ethanolic extract of two species of Origanum and essential oil of plant Origanum vulgare were investigated and also the total phenolic and flavonoid content measured. The radical scavenging activity was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Total phenolic and flavonoid ...

A comparison of antioxidant capacity and some lipoprotein values in swimmers and sedentary subjects

OpenAIRE

Gökhan, İsmail; Aktaş, Yakup; Arikan, Gökhan

2014-01-01

Increased oxygen consumption as a result of the exercise also increases the free radical production. These free radicals are neutralized by a defence mechanism consisting of enzymatic and non-enzymatic antioxidants. Training can have positive or negative effects on oxidative stress depending on the load and type of the training or the status of the individual prior to it. The purpose of this study is to search the capacity of lipoproteins, total oxidant and antioxidant in swimmers and sedenta...

Evaluation of Radical Scavenging Activity of Sempervivum tectorum and Corylus avellana Extracts with Different Phenolic Composition.

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Alberti, Ágnes; Riethmüller, Eszter; Béni, Szabolcs; Kéry, Ágnes

2016-04-01

Semnpervivum tectorum L. and Corylus avellana L. are traditional herbal remedies exhibiting antioxidant activity and representing diverse phenolic composition. The aim of this study was to reveal the contribution of certain compounds to total radical scavenging activity by studying S. tectorum and C. avellana extracts prepared with solvents of different selectivity for diverse classes of phenolics. Antioxidant activity of S. tectorum and C. avellana samples was determined in the ABTS and DPPH radical scavenging assays, and phenolic composition was evaluated by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Correlations between antioxidant activity and phenolic content of houseleek extracts have been revealed. Significant differences regarding antioxidant activity have been shown between S. tectorum 80% (v/v) methanol extract and its fractions. Additionally, synergism among the constituents present together in the whole extract was assumed. Significantly higher radical scavenging activity of hazel extracts has been attributed to the differences in phenolic composition compared with houseleek extracts.

Evaluation of Garlic Cultivars for Polyphenolic Content and Antioxidant Properties

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Cheng, Siqiong; Li, Panpan; Du, Junna; Chang, Yanxia; Meng, Huanwen

2013-01-01

Two phenolic compound parameters (total phenolic and flavonoid contents) and 5 antioxidant parameters (DPPH [2, 2-diphenyl-1-picrylhydrazyl] radical scavenging activity, HRSC (hydroxyl radical scavenging capacity), FRAP (ferric ion reducing antioxidant power), CUPRAC (cupric ion reducing antioxidant capacity), and MCA (metal chelating activity) were measured in bulbs and bolts of 43 garlic cultivars. The bulbs of cultivar ‘74-x’ had the highest phenolic content (total phenolic, flavonoids) and the strongest antioxidant capacity (DPPH, FRAP, and CUPRAC), followed by bulbs of cultivar ‘Hanzhong purple’; the bulbs of cultivar ‘Gailiang’ had the lowest phenolic content and antioxidant capacity (FRAP, CUPRAC, MCA). The bolts of ‘Hanzhong purple’ also had higher phenolic content. Principal components analysis (PCA) separated the cultivars into 3 groups according to phenolic and flavonoid contents and strength of antioxidant activity. The first group had higher HRSC, FRAP, and flavonoid content; the second group had higher total phenolic content and MCA; some cultivars in the third group had higher HRSC and FRAP. All 8 test garlic bulb extracts successfully prevented Human Vascular Endothelial Cell death and significantly prevented reactive-oxygen species (ROS) formation in oxidative stress model, in which cultivar ‘74-x’ had highest protection capability, following by cultivar ‘Hanzhong purple’, and the bulbs of cultivar ‘No. 105 from Korea’ had the lower protection capability against cell death and ROS formation. The protection capability in vivo of these garlic cultivars was consistent with their phenolic content and antioxidant capacity. PMID:24232741

Salivary Total Antioxidant Capacity and Lipid Peroxidation in Patients with Erosive Oral Lichen Planus

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Atena Shirzad

2014-03-01

Full Text Available Background and aims. Oral lichen planus is a common chronic inflammatory disease of the oral mucosa with malignant potential, pathogenesis of which is not still well known. Free radicals and reactive oxygen species can play an important role in the pathogenesis of oral lichen planus. The aim of this study was to investigate salivary oxidative stress and antioxidant systems in patients with oral lichen planus. Materials and methods. In this case-control study, 30 patients with oral lichen planus (case group and 30 age- and gender-matched healthy subjects (control group, referring to Dental School of Babol University of Medical Sciences, were selected using simple sampling method. Unstimulated saliva of the two groups was collected. Salivary total antioxidant capacity (TAC and lipid peroxidation products were investigated and compared, using ferric reducing antioxidant power (FRAP and thiobarbituric acid reactive substance (TBARS methods, respectively. Data were analyzed using Student’s ttest. Results. The mean and standard deviation of salivary TAC in patients with oral lichen planus (297.23 ± 149.72 μM was significantly lower than that in the controls (791.43±183.95 μM; P < 0.0001, and mean and standard deviation of salivary malondialdehyde (MDA (0.49 ± 0.30 μM was remarkably higher in oral lichen planus patients compared to the control group (0.15 ± 0.11 μM (P < 0.0001. TAC was also reduced in both groups in line with an increase in the level of MDA (P < 0.0001, r = −0.48. Conclusion. The results of this study suggested that an increase in oxidative stress and an imbalance in antioxidant defense system in the saliva of oral lichen planus patients may be involved in the pathogenesis of oral lichen planus.

Salivary total antioxidant capacity and lipid peroxidation in patients with erosive oral lichen planus.

Science.gov (United States)

Shirzad, Atena; Pouramir, Mahdi; Seyedmajidi, Maryam; Jenabian, Niloofar; Bijani, Ali; Motallebnejad, Mina

2014-01-01

Background and aims. Oral lichen planus is a common chronic inflammatory disease of the oral mucosa with malignant potential, pathogenesis of which is not still well known. Free radicals and reactive oxygen species can play an important role in the pathogenesis of oral lichen planus. The aim of this study was to investigate salivary oxidative stress and antioxidant systems in patients with oral lichen planus. Materials and methods. In this case-control study, 30 patients with oral lichen planus (case group) and 30 age-and gender-matched healthy subjects (control group), referring to Dental School of Babol University of Medical Sciences, were selected using simple sampling method. Unstimulated saliva of the two groups was collected. Salivary total antioxidant capacity (TAC) and lipid peroxidation products were investigated and compared, using ferric reducing antioxidant power (FRAP) and thiobarbituric acid reactive substance (TBARS) methods, respectively. Data were analyzed using Student' t-test. Results. The mean and standard deviation of salivary TAC in patients with oral lichen planus (297.23 ± 149.72 μM) was significantly lower than that in the controls (791.43 ± 183.95 μM; P & 0.0001), and mean and standard deviation of salivary malondialdehyde (MDA) (0.49 ± 0.30 μM) was remarkably higher in oral lichen planus patients compared to the control group (0.15 ± 0.11 μM) (P & 0.0001). TAC was also reduced in both groups in line with an increase in the level of MDA (P & 0.0001, r = -0.48). Conclusion. The results of this study suggested that an increase in oxidative stress and an imbalance in antioxidant defense system in the saliva of oral lichen planus patients may be involved in the pathogenesis of oral lichen planus.

Total phenols and antioxidant activities of natural honeys and propolis collected from different geographical regions of Ethiopia

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D. Sime

2015-07-01

Full Text Available In this study, ten honey and five propolis samples from different geographical origins were tested. Both honey and propolis samples showed high content of total phenolic compounds (330-610 mg gallic acid equivalent (GAE/100 g honey; 365-1022 mg GAE/g ethanol extract of propolis (EEP. The total flavonoids ranged from (15.1-42.6 mg catechin equivalent (CE/100 g for honey; to 123-74 mg CE/g for EEP. These honeybee products of Ethiopia had high total radical scavenging properties with respect to 2,2-diphenyl-1-picryl-hydrazyl (DPPH; 18.1-59.8% and 48.6-87.8% for honey and EEP respectively. Furthermore, the hydroxymethylfurfural (HMF of the honey samples was found to be low with a mean value of 4.8 mg/kg suggesting that the samples were of good quality. The antioxidant properties of the products showed a good correlation (r2 = 0.50-0.82 with their polyphenolic contents.

Phenolic composition and antioxidant properties of koose, a deep-fat fried cowpea cake.

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Apea-Bah, Franklin B; Serem, June C; Bester, Megan J; Duodu, Kwaku G

2017-12-15

Koose, a West African delicacy, is a side dish prepared by deep frying thick cowpea paste. The current research determined the effect of deep-fat frying of cowpea paste on its total phenolic content (TPC), phenolic composition and antioxidant properties. Four cowpea cultivars comprising two reddish-brown, a brownish-cream and cream phenotypes were used. Liquid chromatography-mass spectrometry was used to determine phenolic composition of the samples. TPC was determined using Folin-Ciocalteu method while radical scavenging capacities were by Trolox equivalent antioxidant capacity, oxygen radical absorbance capacity and nitric oxide scavenging assays. The phenolic acids identified included benzoic and cinnamic acid derivatives. The predominant flavonoid classes were flavan-3-ols and flavonols. Deep-fat frying of the cowpea pastes decreased their TPC, radical scavenging capacities and total quantified flavonoids. The koose inhibited radical-induced oxidative cellular and DNA damage. It is concluded that koose is a potential functional food that can contribute to alleviating radical-induced oxidative stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antioxidant and antimicrobial activities of Bauhinia racemosa L. stem bark

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Kumar R.S.

2005-01-01

Full Text Available The present study was carried out to evaluate the antioxidant and antimicrobial activities of a methanol extract of Bauhinia racemosa (MEBR (Caesalpiniaceae stem bark in various systems. 1,1-Diphenyl-2-picryl-hydrazyl (DPPH radical, superoxide anion radical, nitric oxide radical, and hydroxyl radical scavenging assays were carried out to evaluate the antioxidant potential of the extract. The antioxidant activity of the methanol extract increased in a concentration-dependent manner. About 50, 100, 250, and 500 µg MEBR inhibited the peroxidation of a linoleic acid emulsion by 62.43, 67.21, 71.04, and 76.83%, respectively. Similarly, the effect of MEBR on reducing power increased in a concentration-dependent manner. In DPPH radical scavenging assays the IC50 value of the extract was 152.29 µg/ml. MEBR inhibited the nitric oxide radicals generated from sodium nitroprusside with an IC50 of 78.34 µg/ml, as opposed to 20.4 µg/ml for curcumin. Moreover, MEBR scavenged the superoxide generated by the PMS/NADH-NBT system. MEBR also inhibited the hydroxyl radical generated by Fenton's reaction, with an IC50 value of more than 1000 µg/ml, as compared to 5 µg/ml for catechin. The amounts of total phenolic compounds were also determined and 64.7 µg pyrocatechol phenol equivalents were detected in MEBR (1 mg. The antimicrobial activities of MEBR were determined by disc diffusion with five Gram-positive, four Gram-negative and four fungal species. MEBR showed broad-spectrum antimicrobial activity against all tested microorganisms. The results obtained in the present study indicate that MEBR can be a potential source of natural antioxidant and antimicrobial agents.

Ultrasound-Assisted Extraction of Total Flavonoids from Corn Silk and Their Antioxidant Activity

OpenAIRE

Zheng, Ling-Li; Wen, Guan; Yuan, Min-Yong; Gao, Feng

2016-01-01

Object. Ultrasound-assisted extraction of total flavonoids from corn silk and their antioxidant activities were studied. Methods. Response surface methodology was adopted to optimize the extraction conditions and antioxidant activities of the extracted total flavonoids were detected through ferric reducing antioxidant power (FRAP) assay. Results. Through a three-level, three-variable Box-Behnken design of response surface methodology (RSM) adopting yield as response, the optimal conditions we...

Antioxidants in food

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Đilas Sonja M.

2002-01-01

Full Text Available This paper attempts to lead the reader an understanding of what free radicals are and how they can form during lipid oxidation. Also, it provides some information out natural antioxidants (tocopherols and tocotrienols flavonoids, polyphenols, tannines, melanoidihes, carotenoids, ascorbates and the echanisms of their protection from radical damage. The sources of natural antioxidants are: oil seeds, teas, vegetables, fruits, spices and herbs.

Combination of Antioxidants from Different Sources Could Offer Synergistic Benefits: A Case Study of Tea and Ginger Blend.

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Makanjuola, Solomon A; Enujiugha, Victor N; Omoba, Olufunmilayo S; Sanni, David M

2015-11-01

Tea and ginger are plants with high antioxidant potential. Combinations of antioxidants from different sources could also produce synergistic antioxidant effects. This study investigated the influence of solvent on antioxidant content of tea, ginger, and tea + ginger blends. Under the investigated extraction conditions, water was the most effective extraction solvent to maximise peroxide scavenging and iron chelating activity of tea, ginger, and their blends. Aqueous ethanol was the most effective solvent to maximise ABTS radical scavenging activity and ethanol was the best solvent to maximise DPPH radical scavenging activity. A good multivariate regression model that explains the relationship between the total flavonoid content of the extracts and their antioxidant activities was obtained (R2 and Q2 of 0.93 and 0.83, respectively). Extracts of tea-ginger blends exhibited synergistic effects in their ABTS and DPPH radical scavenging activity.

Evaluation of total polyphenol content and antioxidant capacity of different verity lupin seeds

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Ismael Sulaiman Dalaram

2017-01-01

Full Text Available Legumes, including lupins, beans, lentil and chickpea, are one of the most important crops in the world because of their nutritional quality. Lupin seeds have been used as human food and animal feed since ancient times. It was known that antioxidant photochemical in foods have many health benefits including prevention of various diseases associated with oxidative stress such as cancer, cardiovascular disease, neuro-degeneration and diabetes. Lupin grains are rich sources of complex carbohydrates, protein, vitamins and minerals. Antioxidants can be found naturally in foods. Total polyphenols content and antioxidant activity were measured in four varieties of lupin, namely in white lupin, blue lupin, yellow lupin and Mutabilis lupin species. A majority of antioxidants naturally present in foods occur in phenolic structures and especially in flavonoid structures. The content of the total polyphenols was determined by using the Folin-Ciocalteu reagent (FCR. Antioxidant activity was measured by using a compound DPPH˙ (2.2-diphenyl-1-picrylhydrazyl. In the present experiment according to the average contents of total polyphenols (TPC in dry matter of lupin seeds there was the following line: L. Angustifolius (blue lupin (696.212 mg GAE.100g-1 > L. Albus (white lupin (614.13 mg GAE.100g-1 > L. Luteus (yellow lupin (467.78 mg GAE.100g-1 > L. Mutabilis (pearl lupin (367.36 mg GAE.100g-1. Based on the measured values of total antioxidant capacity (TAC of lupin samples can be classified as follows: L. Albus (white lupin (43.44% >L. Angustifolius (blue lupin (38.27% >L. Luteus (yellow lupin (22.29% >L. Mutabilis (Pearl lupin (20.80%. The relationship of antioxidant capacity with total polyphenolic was discussed. According to used statistical analyzes. Correlation between the phenolic contents and antioxidant capacity was significantly positive (r = 0.88. Our results confirmed that legumes can be a good source of bioactive compounds in the human nutrition

Chemical composition and antioxidant activities of Broussonetia papyrifera fruits.

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Jie Sun

Full Text Available Fruits of Broussonetia papyrifera from South China were analyzed for their total chemical composition, and antioxidant activities in ethanol and aqueous extracts. In the fruit of this plant, the crude protein, crude fat and carbohydrates was 7.08%, 3.72% and 64.73% of dry weight, respectively. The crude protein, crude fat and carbohydrates were 15.71%, 20.51% and 36.09% of dry weight, respectively. Fatty acid and amino acid composition of the fruit were analyzed. Unsaturated fatty acid concentration was 70.6% of the total fatty acids. The percentage of the essential amino acids (EAAs was 40.60% of the total amino acids. Furthermore, B. papyrifera fruit are rich in many mineral elements and vitamins. Total phenolic content was assessed using the Folin-Ciocalteau assay, whereas antioxidant activities were assessed by measuring the ability of the two extracts to scavenge DPPH radicals, inhibit peroxidation, and chelate ferric ions. Their reducing power was also assessed. Results indicated that the aqueous extract of B. papyrifera was a more potent reducing agent and radical-scavenger than the ethanol extract. GC-MS analysis of the ethanol extract showed the presence of some acid-containing compounds. The changes in total phenolic content and antioxidant capacity in B. papyrifera from four different regions grown under normal conditions were assessed. The antioxidant activity of different extracts was positively associated with their total phenolic content. These results suggest that the fruit of B. papyrifera could be used in dietary supplement preparations, or as a food additive, for nutritional gain, or to prevent oxidation in food products.

Comparative total phenolic content, anti-lipase and antioxidant ...

African Journals Online (AJOL)

Total phenol values are expressed in terms of Gallic acid equivalent (w/w of dry mass). Aframomum melegueta exhibited the highest phenolic content of 60.4 ± 2.36 mgGAE/g, a percentage antioxidant activity of 86.6 % at 200μg/ml and percentage lipase inhibition of 89% at 1mg/ml while Aframomum danielli revealed a total ...

Low-temperature matrix effects on orientational motion of Methyl radical trapped in gas solids: Angular tunneling vs. libration

Science.gov (United States)

Dmitriev, Yurij A.; Zelenetckii, Ilia A.; Benetis, Nikolas P.

2018-05-01

EPR investigation of the lineshape of matrix -isolated methyl radical, CH3, spectra recorded in solid N2O and CO2 was carried out. Reversible temperature-dependent line width anisotropy was observed in both matrices. This effect is a fingerprint of the extra-slow radical rotation about the in-plane C2 axes. The rotation was found to be anisotropic and closely correlated to the orientational dynamics of the matrix molecules. It was suggested that a recently discovered "hoping precession" effect of matrix molecules in solid CO2 is a common feature of matrices of the linear molecules CO, N2O, and CO2. A new low-temperature matrix effect, referred to as "libration trap", was proposed which accounts for the changing CH3 reorientational motion about the radical C3-axis from rotation to libration. Temperature dependence of the intensity of the EPR satellites produced by these nonrotating-but librating methyls was presented. This allowed for a rough estimation of the rotation hindering potential due to correlation mismatch between the radical and the nearest matrix molecules' librations.

Antioxidant capacity of Macaronesian traditional medicinal plants.

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Tavares, Lucélia; Carrilho, Dina; Tyagi, Meenu; Barata, David; Serra, Ana Teresa; Duarte, Catarina Maria Martins; Duarte, Rui Oliveira; Feliciano, Rodrigo Pedro; Bronze, Maria Rosário; Chicau, Paula; Espírito-Santo, Maria Dalila; Ferreira, Ricardo Boavida; dos Santos, Cláudia Nunes

2010-04-12

The use of many traditional medicinal plants is often hampered by the absence of a proper biochemical characterization, essential to identify the bioactive compounds present. The leaves from five species endemic to the Macaronesian islands with recognized ethnobotanical applications were analysed: Apollonias barbujana (Cav.) Bornm., Ocotea foetens (Ainton) Baill, Prunus azorica (Mouill.) Rivas-Mart., Lousã, Fern. Prieto, E. Días, J.C. Costa & C. Aguiar, Rumex maderensis Lowe and Plantago arborescens Poir. subsp. maderensis (Dcne.) A. Hans. et Kunk.. Since oxidative stress is a common feature of most diseases traditionally treated by these plants, it is important to assess their antioxidant capacity and determine the molecules responsible for this capacity. In this study, the antioxidant capacity of these plants against two of the most important reactive species in human body (hydroxyl and peroxyl radicals) was determined. To trace the antioxidant origin total phenol and flavonoid contents as well as the polyphenolic profile and the amount of trace elements were determined. There was a wide variation among the species analysed in what concerns their total leaf phenol and flavonoid contents. From the High Performance Liquid Chromatography (HPLC) electrochemically detected peaks it was possible to attribute to flavonoids the antioxidant capacity detected in A. barbujana, O. foetens, R. maderensis and P. azorica extracts. These potential reactive flavonoids were identified for A. barbujana, R. maderensis and P. azorica. For R. maderensis a high content (7 mg g-1 dry weight) of L-ascorbic acid, an already described antioxidant phytomolecule, was found. A high content in selenomethionine (414.35 microg g-1 dry weight) was obtained for P. arborescens subsp. maderensis extract. This selenocompound is already described as a hydroxyl radical scavenger is reported in this work as also possessing peroxyl radical scavenging capacity. This work is a good illustration of

Comparative polyphenolic content and antioxidant activities of Genista tinctoria L. and Genistella sagittalis (L.) Gams (Fabaceae).

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Hanganu, Daniela; Olah, Neli Kinga; Benedec, Daniela; Mocan, Andrei; Crisan, Gianina; Vlase, Laurian; Popica, Iulia; Oniga, Ilioara

2016-01-01

The aim of this study was focused on the polyphenolic composition and antioxidant capacity of Genista tinctoria L. and Genistella sagittalis (L.) Gams. A qualitative and quantitative characterization of the main phenolic compounds from the extracts were carried out using a HPLC-MS method. The total polyphenolic and flavonoid content was spectrophotometrically determined. The antioxidant activity towards various radicals generated in different systems was evaluated usingDPPH bleaching method, Trolox equivalent antioxidant capacity assay (TEAC) and Oxygen radical absorbance capacity (ORAC), and all indicated that G. tinctoria extract was more antioxidant than G. sagittalis extract.That was in good agreement with the total polyphenolic and flavonoidic content.Chlorogenic acid, p-coumaric acid, isoquercitrin and apigenin were identified in bothspecies. Caffeic acid, ferulic acid, hyperoside, rutin, quercitrin and luteolin were found only in G. tinctoria, while quercetin was determined in G. sagittalis.

Measurement of the total antioxidant response using a novel automated method in subjects with nonalcoholic steatohepatitis

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Sarifakiogullari Serpil

2005-11-01

Full Text Available Abstract Background Oxidative stress, an increase in oxidants and/or a decrease in antioxidant capacity, is one of the potential biochemical mechanisms involved in the pathogenesis of nonalcoholic steatohepatitis. We aimed to investigate the total antioxidant response using a novel automated method in nonalcoholic steatohepatitis subjects. As a reciprocal measure, we also aimed to determine total peroxide level in the same plasma samples. Methods Twenty-two subjects with biopsy proven nonalcoholic steatohepatitis and 22 healthy controls were enrolled. Total antioxidant response and total peroxide level measurements were done in all participants. The ratio percentage of total peroxide level to total antioxidant response was regarded as oxidative stress index. Results Total antioxidant response of subjects with nonalcoholic steatohepatitis was significantly lower than controls (p In subjects with nonalcoholic steatohepatitis, fibrosis score was significantly correlated with total peroxide level, total antioxidant response and oxidative stress index (p 0.05. Conclusion Nonalcoholic steatohepatitis is associated with increased oxidant capacity, especially in the presence of liver fibrosis. The novel automated assay is a reliable and easily applicable method for total plasma antioxidant response measurement in nonalcoholic steatohepatitis.

Antioxidants Potential of the Filamentous Fungi (Mucor circinelloides

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Ahsan Hameed

2017-10-01

Full Text Available Three important strains of Mucor circinelloides grown in complete and minimal media for specified period (72 h, 120 h and 168 h under submerged fermentation conditions were investigated for their potential antioxidants/secondary metabolite production. All mycelial extracts demonstrated effective antioxidant activities in terms of β-carotene/linoleic acid bleaching, radical scavenging, reduction of metal ions and chelating abilities against ferrous ions. Different extraction methods and solvent systems affected the recovery yield and antioxidant activities of the extracts significantly (p ≤ 0.05. Ethanolic extracts were found to be rich source of antioxidant components and subsequently more effective in antioxidant properties. Fermentation period and media used also significantly affected (p ≤ 0.05 the antioxidant production and the resulting antioxidant properties. The (ethanolic extracts of all the strains from late exponential growth phase (120 h showed highest antioxidant production with topmost reducing, chelating and radical scavenging capabilities. Strain MC277.49 was found to be the highest producer of antioxidants followed by MC108.16 and WJ11. Phenolic compounds were detected significantly in higher (p ≤ 0.05 amount succeeded by the condensed tannins and flavonoids. Total phenol content of each extract was attributed to overall antioxidant capacity. Submerged fermentation with nutritional stress conditions were found to be excellent way of producing surplus amount of natural antioxidants/secondary metabolites with their vast potential commercial application in food and pharmaceutical industries.

Comparison of different tests used in mapping the Greek virgin olive oil production for the determination of its total antioxidant capacity

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Georgiou, Constantinos A.

2010-03-01

Full Text Available This study aims to map the total antioxidant capacity (TAC of 50 Greek olive oil samples from the 2005-2006 season according to production region and cultivar and to compare the 2, 2’-azino-bis (3-ethylbenzo-thiazoline-6- sulfonic acid (ABTS, 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH and Folin-Ciocalteu tests for use with olive oil. Antioxidant capacities determined in the hydrophilic fraction range between 5.42 - 22.5 mM gallic acid Kg-1 olive oil for the ABTS method and 1.29 - 9.95 mM Kg-1 for the DPPH method while in total, olive oil TAC ranges between 77 - 177 mM Kg-1 as assessed by the DPPH method. The results of total phenol content range between 3.8 and 29.4 mM Kg-1 olive oil. Total phenol content correlates with total antioxidant capacity assessed in the hydrophilic fraction through the DPPH (r = 0.89 and the ABTS (r = 0.69 assays. The hydrophilic fraction DPPH values correlate significantly with the ABTS values (r = 0.81. However, the DPPH values for total olive oil correlate poorly with the ABTS assay, the Folin-Ciocalteu method and the DPPH assay in hydrophilic fraction. Although total phenolic content shows good correlation with ABTS and DPPH values and could serve as a useful indicator for olive oil antioxidant capacity, the use of a battery of tests contributes to better characterization of the antioxidant capacity of olive oil.El objetivo de este estudio es el mapeo de la actividad antioxidante total (TAC de 50 aceites de oliva Griego de los años 2005-2006 de acuerdo a su región y cultivar, y se comparan los ensayos del ácido 2, 2’-azino-bis (3-etilbenzo-tiazolina- 6-sulfónico (ABTS, del 2,2-difenil-1-picrlhidrazil radical (DPPH y de Folin-Ciocalteu. La capacidad antioxidante determinada en la fracción hidrofílica varió entre 5.42-22.5 mM de ácido gálico Kg-1 de aceite para el método ABTS y 1.29- 9.95 mM Kg-1 de aceite para el método de DPPH mientras que la TAC del aceite de oliva completo varió entre 77-177 m

Antioxidant Capacities and Total Phenolic Contents Enhancement with Acute Gamma Irradiation in Curcuma alismatifolia (Zingiberaceae Leaves

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Sima Taheri

2014-07-01

Full Text Available The present study was conducted in order to assess the effect of various doses of acute gamma irradiation (0, 10, 15, and 20 Gy on the improvement of bioactive compounds and their antioxidant properties of Curcuma alismatifolia var. Sweet pink. The high performance liquid chromatography (HPLC and gas chromatography (GC analysis uncovered that various types of phenolic, flavonoid compounds, and fatty acids gradually altered in response to radiation doses. On the other hand, antioxidant activities determined by 1,1-Diphenyl-2-picryl-hydrazyl (DPPH, ferric reduction, antioxidant power (FRAP, and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS radical scavenging assay showed a higher irradiation level significantly increased the antioxidant properties. This study revealed an efficient effect of varying levels of gamma radiation, based on the pharmaceutical demand to enhance the accumulation and distribution of bioactive compounds such as phenolic and flavonoid compounds, fatty acids, as well as their antioxidant activities in the leaves of C. alismatifolia var. Sweet pink.

Antioxidant activity of raw, cooked and Rhizopus oligosporus fermented beans of Canavalia of coastal sand dunes of Southwest India.

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Niveditha, Vedavyas R; Sridhar, Kandikere R

2014-11-01

The raw and processed (cooked and cooked + solid-state fermented with Rhizopus oligosporus) split beans of two landraces of coastal sand dune wild legumes (Canavalia cathartica and Canavalia maritima) of the southwest coast of India were examined for bioactive compounds (total phenolics, tannins and vitamin C) and antioxidant potential (total antioxidant activity, ferrous-ion chelating capacity, DPPH free radical-scavenging activity and reducing activity). One-way ANOVA revealed significant elevation of bioactive compounds as well as antioxidant activities in fermented beans compared to raw and cooked beans in both legumes (p beans of both legumes were significantly lowest compared to raw and cooked beans (p beans of C. cathartica, while total antioxidant and free radical-scavenging activities of fermented beans of C. maritima were clustered. The present study demonstrated that split beans of coastal sand dune Canavalia fermented by R. oligosporus endowed with high bioactive principles as well as antioxidant potential and thus serve as future nutraceutical source.

Antioxidative activity of extracts from fenugreek seeds (trigonella foenum-graecum)

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Bukhari, S B; Bhanger, M I; Memon, S [University of Sindh, Jamshoro (Pakistan). Dept. of Excellence in Analytical Chemistry

2008-12-15

Spices and herbs possess antioxidant activity and can be applied for preservation of lipid peroxidation in biological systems. Fenugreek (Trigonella foenum-graecum) is an important spice; its dried seeds have wide application in food and beverages as a flavoring additive as well as in medicines. Crude extracts of fenugreek were prepared by soxhelt extraction method with different solvents such as methanol, ethanol, dichloromethane, acetone, hexane and ethyl acetate. Extracts were subjected for the measurement of total phenolic content (TPC) by Folin-Ciocalteu method as well as flavonoid content, chelating activity, reducing power and antioxidant/radical scavenging activity (1,1-diphenyl-2-picryl-hydrazyl (DPPH degree) free radical scavenging activity). Results from different parameters were in agreement with each other. The results reveal that all extracts of the fenugreek exhibit antioxidant activity. These findings suggest that the fenugreek extracts could act as potent source of antioxidants. (author)

Antioxidative activity of extracts from fenugreek seeds (trigonella foenum-graecum)

International Nuclear Information System (INIS)

Bukhari, S.B.; Bhanger, M.I.; Memon, S.

2008-01-01

Spices and herbs possess antioxidant activity and can be applied for preservation of lipid peroxidation in biological systems. Fenugreek (Trigonella foenum-graecum) is an important spice; its dried seeds have wide application in food and beverages as a flavoring additive as well as in medicines. Crude extracts of fenugreek were prepared by soxhelt extraction method with different solvents such as methanol, ethanol, dichloromethane, acetone, hexane and ethyl acetate. Extracts were subjected for the measurement of total phenolic content (TPC) by Folin-Ciocalteu method as well as flavonoid content, chelating activity, reducing power and antioxidant/radical scavenging activity (1,1-diphenyl-2-picryl-hydrazyl (DPPH degree) free radical scavenging activity). Results from different parameters were in agreement with each other. The results reveal that all extracts of the fenugreek exhibit antioxidant activity. These findings suggest that the fenugreek extracts could act as potent source of antioxidants. (author)

Antioxidant activity of oregano, parsley, and olive mill wastewaters in bulk oils and oil-in-water emulsions enriched in fish oil.

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Jimenez-Alvarez, D; Giuffrida, F; Golay, P A; Cotting, C; Lardeau, A; Keely, Brendan J

2008-08-27

The antioxidant activity of oregano, parsley, olive mill wastewaters (OMWW), Trolox, and ethylenediaminetetraacetic acid (EDTA) was evaluated in bulk oils and oil-in-water (o/w) emulsions enriched with 5% tuna oil by monitoring the formation of hydroperoxides, hexanal, and t-t-2,4-heptadienal in samples stored at 37 degrees C for 14 days. In bulk oil, the order of antioxidant activity was, in decreasing order (p oregano > parsley > EDTA > Trolox. The antioxidant activity in o/w emulsion followed the same order except that EDTA was as efficient an antioxidant as OMWW. In addition, the total phenolic content, the radical scavenging properties, the reducing capacity, and the iron chelating activity of OMWW, parsley, and oregano extracts were determined by the Folin-Ciocalteau, oxygen radical absorbance capacity, ferric reducing antioxidant power, and iron(II) chelating activity assays, respectively. The antioxidant activity of OMWW, parsley, and oregano in food systems was related to their total phenolic content and radical scavenging capacity but not to their ability to chelate iron in vitro. OMWW was identified as a promising source of antioxidants to retard lipid oxidation in fish oil-enriched food products.

Total phenol content and antioxidant activity of water solutions of plant extracts

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Mirela Kopjar

2009-01-01

Full Text Available Water solutions of extracts were investigated for total phenol content, flavonoid content and antioxidant activity. Susceptibility to degradation of water solutions of plant extracts, under light and in the dark, during storage at room temperature was investigated in order to determine their stability prior to their application for fortification of food products. Large dispersion of total phenol (TP content in the investigated model solutions of selected extracts (olive leaves, green tea, red grape, red wine, pine bark PE 5:1, pine bark PE 95 %, resveratrol, ranging from 11.10 mg GAE/100 mL to 92.19 mg GAE/100 mL was observed. Consequently, large dispersion of total flavonoids (TF content (8.89 mg to 61.75 mg CTE/100 mL was also observed. Since phenols have been mostly responsible for antioxidant activity of extracts, in most cases, antioxidant activity followed the TP content. That was proven by estimation of correlation coefficient between the total phenol content and antioxidant activity. Correlation coefficients between investigated parameters ranged from 0.5749 to 0.9604. During storage of 5 weeks at room temperature loss of phenols and flavonoids occurred. Antioxidant activity decreased with the decrease of TP and TF content. Degradations of phenols and flavonoids were more pronounced in samples stored at light.

Antioxidant activity of hydroalcoholic leaf extracts of Psidium guajava and Persea Americana, an invitro study

International Nuclear Information System (INIS)

Kumar, Amith; Kumarachandra, Reshma; Rai, Rajalakshmi; Rao, Satish; Suchetha Kumari; Joshi, Manjunath

2013-01-01

Ionizing radiation produce deleterious effects in the living organisms. Rapid technological advancement has increased human exposure to ionizing radiations enormously. Several plants have been screened for their radio protective ability and the hunt for identifying many more safe, nontoxic and effective ones is in progress. The aim of the present study was to evaluate the antioxidant activity in hydro alcoholic leaf extract of Psidium guajava (guava) and Persea americana (avocado). The antioxidant assay such as 2,2-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) free radical scavenging assay, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay, chelation of iron by plant extract, hydroxyl radical scavenging assay, ferric reducing antioxidant potential (FRAP), and total antioxidant activity of extract was analyzed using spectrophotometer. Phytochemical screening and HPLC analysis of leaf extracts were also performed. The results indicated that the IC50 value of hydro alcoholic leaf extract of P.guajava and P. americana were 14 μg/ml and 15 μg/ml in ABTS free radical scavenging assay, 4 μg/ml and 2.5 μg/ml in DPPH free radical scavenging assay, 7.2 μg/ml and 8.4 μg/ml in chelation of iron by plant extract, 2 μg/ml and, 4.3 μg/ml in hydroxyl radical scavenging assay and effective concentration(EC50) was 57.80 μg/ml and 87.56 μg/ml in FRAP assay respectively. The results for total antioxidant activity indicated that 242.3 μg/ml of P.guajava and 432.7 μg/ml of P.americana extract was equivalent to 100 μg/ml of standard qurecetin respectively. Qualitative analysis of hydroalcoholic leaf extracts revealed the presence of flavonoids, tannins, saponions, terpenoids, and glycosides. HPLC analysis confirmed the presence of flavonoids qurecetin and rutin in leaf extracts on comparison with standard compounds. Our study showed that hydro alcoholic leaf extracts of Psidium guajava and Persea americana act as strong antioxidant and free

{alpha}-Tocopherol impact on oxy-radical induced free radical decomposition of DMSO: Spin trapping EPR and theoretical studies

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Jerzykiewicz, Maria, E-mail: Mariaj@wchuwr.pl [Faculty of Chemistry, Wroclaw University, 14 F. Joliot-Curie St., 50-383 Wroclaw (Poland); Cwielag-Piasecka, Irmina; Witwicki, Maciej; Jezierski, Adam [Faculty of Chemistry, Wroclaw University, 14 F. Joliot-Curie St., 50-383 Wroclaw (Poland)

2011-05-26

Graphical abstract: {alpha}-Tocopherol inhibits the oxidation of {center_dot}CH{sub 3} to {center_dot}OCH{sub 3}. Display Omitted Highlights: {yields} {alpha}-Tocopherol does not inhibit the oxidation of DMSO to {center_dot}CH{sub 3}. {yields} {alpha}-Tocopherol inhibits the oxidation of {center_dot}CH{sub 3} to {center_dot}OCH{sub 3}. {yields} {alpha}-Tocopherol does not inhibit the oxidation of PBN. {yields} The structures of observed spin adducts were theoretically confirmed. - Abstract: EPR spin trapping and theoretical methods such as density functional theory (DFT) as well as combined DFT and quadratic configuration interaction approach (DFT/QCISD) were used to identify the radicals produced in the reaction of oxy-radicals and dimethyl sulfoxide (DMSO) in the presence and absence of {alpha}-tocopherol. Additionally, the mixtures of {alpha}-tocopherol with linolenic acid and glyceryl trilinoleate as well as bioglycerols (glycerol fractions from biodiesel production) were tested. {alpha}-Tocopherol inhibited oxidation of the main decomposition product of DMSO, {center_dot}CH{sub 3} to {center_dot}OCH{sub 3} but did not prevent the transformation process of N-t-butyl-{alpha}-phenylnitrone (PBN) into 2-methyl-2-nitrosopropane (MNP). Theoretical investigations confirmed the structures of proposed spin adducts and allowed to correlate the EPR parameters observed in the experiment with the spin adducts electronic structure.

Total Content of Phenolics and Antioxidant Activity in Crispbreads with Plant By-product addition

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Konrade Daiga

2017-11-01

Full Text Available Vegetable processing in food industry results in significant amount of by-products – peel, mark, bark, seeds still rich in bioactive compounds. Apple, carrot and pumpkin peel and mark may be used for production of crispbreads as functional ingredients. The objective of this study is to investigate the stability of total phenolic content (TPC and antioxidant activity after high temperature and short time (HTST extrusion cooking of a wheat and rice-based crispbreads with addition of apple, carrot and pumpkin by-products obtained after juice extraxtion and dried. Raw materials for crispbread production were wheat flour, rice flour, wheat bran (72%, 24% and 4% respectively with addition of microwave–vacuum dried by-product powder in different amount (5%, 10%, 15%, 20%. Extrusion process was performed by using a laboratory singlescrew extruder GÖTTFERT 1 screw Extrusiometer L series (Germany. Total phenolic content (TPC was determined using the Folin Ciocalteu method. Antioxidant activity was evaluated by free radical 2, 2-diphenyl-1-picrylhydrazyl (DPPH antioxidant scavenging activity using a modified colorimetric method. Comparing different raw formulations, it was observed that the TPC of the apple by-product flour was significantly higher (p < 0.05 than in carrot and pumpkin flour. TPC in cereal-based crispbread was 36.06±1.15 before extrusion and 13.90±1.01 mg GAEg-1 DW (milligram Gallic acid equivalent per 100 g of dry weight (mg GAE 100 g−1 DW after extrusion. Addition of apple BPF increased TPC in crispbreads to 106.25±2.08, carrot BPF 84.73±3.45 and pumpkin BPF to 108.82±1.04 mg GAEg−1 DW. Antioxidant activity of control sample was 1.07±0.01mg TE (Trolox equivalents g−1 DW but in samples with addition of 20% apple by-products, it reached 3.77±0.02 TE g−1 DW for samples wih 20% carrot by-products reached 2.52±0.03TE g−1 DW and for samples wih 20% pumpkin by-products reached 3.77±0.02 TE g−1 DW.

Antioxidant activity of the giant jellyfish Nemopilema nomurai measured by the oxygen radical absorbance capacity and hydroxyl radical averting capacity methods.

Science.gov (United States)

Harada, Kazuki; Maeda, Toshimichi; Hasegawa, Yoshiro; Tokunaga, Takushi; Ogawa, Shinya; Fukuda, Kyoko; Nagatsuka, Norie; Nagao, Keiko; Ueno, Shunshiro

2011-01-01

The giant jellyfish Nemopilema nomurai (reaching sizes of up to 2 m diameter and 150 kg), which forms dense blooms, has caused extensive damage to fisheries by overloading trawl nets, while its toxic nematocysts cause dermatological symptoms. Giant jellyfish are currently discarded on the grounds of pest control. However, the giant jellyfish is considered to be edible and is part of Chinese cuisine. Therefore, we investigated whether any benefits for human health may be derived from consumption of the jellyfish in order to formulate medicated diets. Antioxidant activity of Nemopilema nomurai was measured using the oxygen radical absorbance capacity (ORAC) and hydroxyl radical averting capacity (HORAC) methods. Based on the results, the ORAC value of the giant jellyfish freeze-dried sample was 541 µmol trolox equivalent (TE)/100 g and the HORAC value was 3,687 µmol gallic acid equivalent (GAE)/100 g. On the other hand, the IC50 value of hydroxyl radical scavenging activity measured by using the electron spin resonance method was 3.3%. In conclusion, the results suggest that the freeze-dried powder of the giant jellyfish Nemopilema nomurai is a potentially beneficial food for humans.