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Sample records for major radical scavenger

  1. Antioxidant and radical scavenging properties of curcumin.

    PubMed

    Ak, Tuba; Gülçin, Ilhami

    2008-07-10

    Curcumin (diferuoyl methane) is a phenolic compound and a major component of Curcuma longa L. In the present paper, we determined the antioxidant activity of curcumin by employing various in vitro antioxidant assays such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH*) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, N,N-dimethyl-p-phenylenediamine dihydrochloride (DMPD) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination by the Fe(3+)-Fe(2+) transformation method, superoxide anion radical scavenging by the riboflavin/methionine/illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe(2+)) chelating activities. Curcumin inhibited 97.3% lipid peroxidation of linoleic acid emulsion at 15 microg/mL concentration (20 mM). On the other hand, butylated hydroxyanisole (BHA, 123 mM), butylated hydroxytoluene (BHT, 102 mM), alpha-tocopherol (51 mM) and trolox (90 mM) as standard antioxidants indicated inhibition of 95.4, 99.7, 84.6 and 95.6% on peroxidation of linoleic acid emulsion at 45 microg/mL concentration, respectively. In addition, curcumin had an effective DPPH* scavenging, ABTS*(+) scavenging, DMPD*(+) scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe(3+)) reducing power and ferrous ions (Fe(2+)) chelating activities. Also, BHA, BHT, alpha-tocopherol and trolox, were used as the reference antioxidant and radical scavenger compounds. According to the present study, curcumin can be used in the pharmacological and food industry because of these properties. PMID:18547552

  2. Radical scavengers from heavy hydrocarbons

    SciTech Connect

    Kubo, Junichi

    1996-10-01

    The hydrogen-donating properties of some hydrocarbons form the basis for processes such as coal liquefaction and heavy oil upgrading. However, these hydrocarbons have seldom been used for other purposes, because their potential applications have not been well recognized. Research has indicated that these hydrogen-donating hydrocarbons can be used in important reactions as radical scavengers and have properties particular to those of pure hydrocarbons without functional groups containing heteroatoms. Over years of study researchers have found that pure hydrocarbons with radical-scavenging effects nearly as high as those in conventional hindered phenolic antioxidants can be produced from petroleum, and these hydrogen-donating hydrocarbons exhibit such effects even in oxidative atmospheres (i.e., they function as antioxidants). He has also shown that these mixtures have some properties particular to pure hydrocarbons without functional groups containing heteroatoms, and they`ve seen that a mechanism based on the steric effects appears when these hydrocarbons are used in heavy oil hydroprocessing. Hydrogen-donating hydrocarbons should be a viable resource in many applications. In this article, he presents radical-scavenging abilities, characteristics as pure hydrocarbons, and applications on the basis of the studies.

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

    PubMed Central

    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 < 0.05), while that of RBO was preserved after deep-frying of fries. As expected, the concentration of α-tocopherol in PO and γ-tocotrienol in both PO and RBO decreased significantly (p < 0.05) with increased frying. Results also showed that γ-tocotrienol was found to be more susceptible to degradation compared to that of α-tocopherol in both PO and RBO. Interestingly, no significant degradation of α-tocopherol was observed in RBO. It is suggested that the presence of γ-oryzanol and γ-tocotrienol in RBO may have a protective effect on α-tocopherol during deep-frying. PMID:26785067

  4. Radical scavenging activities of niacin-related compounds.

    PubMed

    Ogata, Shin; Takeuchi, Masayo; Teradaira, Shin; Yamamoto, Naokuni; Iwata, Keiko; Okumura, Katsuzumi; Taguchi, Hiroshi

    2002-03-01

    We investigated whether niacin-related compounds had radical-scavenging activity by electron spin resonance methods. Many compounds, but not trigonelline, had radical-scavenging activity against hydroxyl radicals. However, for the nitric oxide radical and 1,1-diphenyl-2-picrylhydrazyl radical, only nicotinic acid hydrazide and isonicotinic acid hydrazide had scavenging activities. These results suggest that the moiety of hydrazide might have an important role in scavenging abilities of various radicals. PMID:12005062

  5. Superoxide anion radical scavenging property of catecholamines.

    PubMed

    Kładna, Aleksandra; Berczyński, Paweł; Kruk, Irena; Michalska, Teresa; Aboul-Enein, Hassan Y

    2013-01-01

    The direct effect of the four catecholamines (adrenaline, noradrenaline, dopamine and isoproterenol) on superoxide anion radicals (O2•) was investigated. The reaction between 18-crown-6-ether and potassium superoxide in dimethylsulfoxide was used as a source of O2•. The reactivity of catecholamines with O2• was examined using chemiluminescence, reduction of nitroblue tetrazolium and electron paramagnetic resonance spin-trapping techniques. 5,5-Dimethyl-1-pyrroline-N-oxide was included as the spin trap. The results showed that the four catecholamines were effective and efficient in inhibiting chemiluminescence accompanying the potassium superoxide/18-crown-6-ether system in a dose-dependent manner over the range 0.05-2 mM in the following order: adrenaline > noradrenaline > dopamine > isoproterenol, with, IC50 = 0.15 ± 0.02 mM 0.21 ± 0.03 mM, 0.27 ± 0.03 mM and 0.50 ± 0.04 mM, respectively. The catecholamines examined also exhibited a strong scavenging effect towards O2• when evaluated this property by the inhibition of nitroblue tetrazolium reduction (56-73% at 1 M concentration). A very similar capacity of O2• scavenging was monitored in the 5,5-dimethyl-1-pyrroline-N-oxide spin-trapping assay. The results suggest that catecholamines tested may involve a direct effect on scavenging O2- radicals. PMID:23319391

  6. Is Silybin the Best Free Radical Scavenger Compound in Silymarin?

    PubMed

    Reina, Miguel; Martínez, Ana

    2016-05-26

    Silymarin is a natural mixture with beneficial properties for health, specifically due to its antiradical characteristics. The major components of this mixture are silybin (SIL), silychristin (SILYC), isosilybin (ISOSIL), silydianin (SILYD), and taxifolin (TAX). In this report, the electronic properties of these substances are investigated using density functional theory calculations, mainly in order to fully understand the free radical scavenger properties of these compounds. Optimized geometries and Raman spectra are reported. These results could be experimentally useful for identifying some of the major components of the mixture. The relative abundance of deprotonated species under physiological conditions is also included. The free radical scavenger capacity is studied in relation to three mechanisms: the single electron transfer (SET), the radical adduct formation (RAF), and the hydrogen atom transfer (HAT). According to this investigation, the HAT mechanism is the most efficient mechanism for scavenging free radicals for these compounds followed by the RAF mechanism where intramolecular hydrogen bonds are formed in order to stabilize the (•)OOH free radical. A particularly important factor is that none of the compounds being studied showed an outstanding antiradical capacity performance compared to the others. In this sense, silymarin is an interesting mixture with antiradical properties and we now know that one single component should be as effective as the mixture. PMID:27149000

  7. Free Radical Scavenging and Antioxidant Activities of Silymarin Components

    PubMed Central

    Anthony, Kevin P.; Saleh, Mahmoud A.

    2013-01-01

    Silymarin is an over the counter food supplement that is sold as a liver enhancement and liver protection preparation. It is a major constituent of the seeds of Silybum marianum which is composed of a mixture of seven major components and several minor compounds. The seven major components: taxifolin, silychristin, silydianin, silybin A, silybin B, iso-silybin A and iso-silybin B were isolated and purified from the crude mixture of silymarin using preparative high performance liquid chromatography to determine which were the most effective for liver protection. Free radical scavenging, hydroxyl radical antioxidant capacity, oxygen radical antioxidant capacity, trolox-equivalent antioxidant capacity and total antioxidant capacity antioxidant activities were determined for each of the individual purified components as well as the crude silymarin mixture. Taxifolin was the most effective component for scavenging free radicals in the DPPH assay with an EC50 of 32 µM far more effective than all other components which showed EC50 ranging from 115 to 855 µM. Taxifolin was also found to be the most effective antioxidant in the oxygen radical antioxidant capacity (ORAC) assay with a trolox equivalent of 2.43 and the second most effective in the hydroxyl radical antioxidant capacity (HORAC) assay with a gallic acid equivalent of 0.57. Other antioxidants assays did not show significant differences between samples. PMID:26784472

  8. Free Radical Scavenging and Cellular Antioxidant Properties of Astaxanthin.

    PubMed

    Dose, Janina; Matsugo, Seiichi; Yokokawa, Haruka; Koshida, Yutaro; Okazaki, Shigetoshi; Seidel, Ulrike; Eggersdorfer, Manfred; Rimbach, Gerald; Esatbeyoglu, Tuba

    2016-01-01

    Astaxanthin is a coloring agent which is used as a feed additive in aquaculture nutrition. Recently, potential health benefits of astaxanthin have been discussed which may be partly related to its free radical scavenging and antioxidant properties. Our electron spin resonance (ESR) and spin trapping data suggest that synthetic astaxanthin is a potent free radical scavenger in terms of diphenylpicryl-hydrazyl (DPPH) and galvinoxyl free radicals. Furthermore, astaxanthin dose-dependently quenched singlet oxygen as determined by photon counting. In addition to free radical scavenging and singlet oxygen quenching properties, astaxanthin induced the antioxidant enzyme paroxoanase-1, enhanced glutathione concentrations and prevented lipid peroxidation in cultured hepatocytes. Present results suggest that, beyond its coloring properties, synthetic astaxanthin exhibits free radical scavenging, singlet oxygen quenching, and antioxidant activities which could probably positively affect animal and human health. PMID:26784174

  9. Free Radical Scavenging and Cellular Antioxidant Properties of Astaxanthin

    PubMed Central

    Dose, Janina; Matsugo, Seiichi; Yokokawa, Haruka; Koshida, Yutaro; Okazaki, Shigetoshi; Seidel, Ulrike; Eggersdorfer, Manfred; Rimbach, Gerald; Esatbeyoglu, Tuba

    2016-01-01

    Astaxanthin is a coloring agent which is used as a feed additive in aquaculture nutrition. Recently, potential health benefits of astaxanthin have been discussed which may be partly related to its free radical scavenging and antioxidant properties. Our electron spin resonance (ESR) and spin trapping data suggest that synthetic astaxanthin is a potent free radical scavenger in terms of diphenylpicryl-hydrazyl (DPPH) and galvinoxyl free radicals. Furthermore, astaxanthin dose-dependently quenched singlet oxygen as determined by photon counting. In addition to free radical scavenging and singlet oxygen quenching properties, astaxanthin induced the antioxidant enzyme paroxoanase-1, enhanced glutathione concentrations and prevented lipid peroxidation in cultured hepatocytes. Present results suggest that, beyond its coloring properties, synthetic astaxanthin exhibits free radical scavenging, singlet oxygen quenching, and antioxidant activities which could probably positively affect animal and human health. PMID:26784174

  10. Angiotensin converting enzyme inhibitors as oxygen free radical scavengers.

    PubMed

    Mira, M L; Silva, M M; Queiroz, M J; Manso, C F

    1993-01-01

    The authors have compared the ability of two non-SH-containing angiotensin converting enzyme (ACE) inhibitors (enalaprilat and lisinopril) with an -SH containing ACE inhibitor (captopril) to scavenge the hydroxyl radical (.OH). All three compounds were able to scavenge .OH radicals generated in free solution at approximately diffusion-controlled rates (10(10) M-1 s-1) as established by the deoxyribose assay in the presence of EDTA. The compounds also inhibited deoxyribose degradation in reaction mixtures which did not contain EDTA but not so effectively. This later findings also suggests that they have some degree of metal-binding capability. Chemiluminescence assays of oxidation of hypoxanthine by xanthine oxidase in the presence of luminol, confirm that the three ACE inhibitors are oxygen free radical scavengers. Our results indicate that the presence of a sulphydryl group in the chemical structure of ACE inhibitors is not relevant for their oxygen free radical scavenging ability. PMID:8244086

  11. Free radical scavenging reactions of sulfasalazine, 5-aminosalicylic acid and sulfapyridine: mechanistic aspects and antioxidant activity.

    PubMed

    Joshi, Ravi; Kumar, Sudheer; Unnikrishnan, M; Mukherjee, T

    2005-11-01

    Reactions of sulfasalazine (SAZ) and its metabolites, 5-aminosalicylic acid (5-ASA) and sulfapyridine (SP), with various oxidizing and reducing free radicals (hydroxyl, haloperoxyl, one-electron oxidizing, lipid peroxyl, glutathiyl, superoxide, tryptophanyl, etc.) have been studied to understand the mechanistic aspects of its action against free radicals produced during inflammation. Nanosecond pulse radiolysis technique coupled with transient spectrophotometry has been used for in situ generation of free radicals and to follow their reaction pathways. The transients produced in these reactions have been assigned and radical scavenging rate constants have been measured. In addition to scavenging of various primary and secondary free radicals by SAZ, 5-ASA and SP, 5-ASA has also been observed to efficiently scavenge radicals of biomolecules. 5-ASA has been found to be the active moiety of SAZ involved in the scavenging of oxidizing free radicals whereas reduction of SAZ produced molecular radical anion. The study suggests that free radical scavenging activity of 5-ASA may be a major path of pharmacological action of SAZ against inflammatory bowel diseases (IBD). PMID:16298742

  12. Free radical scavenging (DPPH) potential in nine Mentha species.

    PubMed

    Ahmad, Nisar; Fazal, Hina; Ahmad, Iftikhar; Abbasi, Bilal Haider

    2012-02-01

    Mentha species are used in every day life in various food items. These species produce valuable secondary metabolites that scavenge toxic free radicals. Toxic free radicals can cause different diseases in the human body. In the present study free radical scavenging potential (1,1-diphenyl-2-picrylhydrazyl scavenging activity) in nine Mentha species were investigated to evaluate and explore new potential sources for natural antioxidants. The activity was performed after different time intervals with incubation period of 30 minutes. The methanolic extracts revealed that significantly higher activity (82%) was observed in Mentha suaveolens, followed by Mentha longifolia (79%), Mentha officinalis (76%) and Mentha piperita, Mentha pulegium, Mentha royleana (75%), respectively. Significantly same activity was observed in Mentha arvensis and Mentha spicata. Lower activity was observed in Mentha citrata (64%). The present study revealed that these species can be used as natural antioxidants. PMID:21646282

  13. Radical scavenging, antioxidant and cytotoxic activity of Brazilian Caatinga plants.

    PubMed

    David, Juceni P; Meira, Marilena; David, Jorge M; Brandão, Hugo N; Branco, Alexsandro; de Fátima Agra, M; Barbosa, M Regina V; de Queiroz, Luciano P; Giulietti, Ana M

    2007-04-01

    Extracts of 32 plants from the Brazilian northeastern semi-arid region called Caatinga were evaluated through DPPH radical scavenging assay, beta-carotene bleaching, and brine shrimp lethality tests (BST). Among the extracts studied Byrsonima cf. gardneriana, Mascagnia coriacea, Cordia globosa, Diodia apiculata and Hypenia salzmannii showed the highest activities in DPPH radical scavenging test. In the beta-carotene bleaching test the highest activities were observed for Passiflora cincinnata, Chamaecrista repens, B. cf. gardneriana, Rollinia leptopetala, Serjania glabrata, Diospyros gaultheriifolia, C. globosa, Mimosa ophtalmocentra, M. coriacea and Lippia cf. microphylla. In contrast, R. leptopetala, Zornia cf. brasiliensis and Leonotis nepetifolia were the most active species in the BST. PMID:17331673

  14. Peroxyl radical scavenging activity of Ginkgo biloba extract EGb 761.

    PubMed

    Maitra, I; Marcocci, L; Droy-Lefaix, M T; Packer, L

    1995-05-26

    Antioxidant mechanisms have been proposed to underlie the beneficial pharmacological effects of EGb 761, an extract from Ginkgo biloba leaves used for treating peripheral vascular diseases and cerebrovascular insufficiency in the elderly. In vitro evidence has been reported that EGb 761 scavenges various reactive oxygen species, i.e. nitric oxide, and the superoxide, hydroxyl, and oxoferryl radicals. However, the ability of EGb 761 to scavenge peroxyl radicals (reactive species mainly involved in the propagation step of lipid peroxidation) has not been investigated. To characterize further the antioxidant action of EGb 761, we measured the protective effects of EGb 761 during: (1) the oxidation of B-phycoerythrin by peroxyl radicals generated in aqueous solution by 2,2'-azobis (2-amidinopropane) hydrochloride (AAPH); and (2) the reaction of luminol or cis-parinaric acid with peroxyl radicals generated from 2,2'-azobis (2,4-dimethylvaleronitrile) (AMVN) in liposomes or in human low density lipoprotein (LDL), respectively. To evaluate the peroxyl radical scavenging activity of EGb 761 in a more physiologically relevant model of damage to lipid-containing systems, we also analyzed the effect of the extract on the oxidation of human LDL exposed to the azo-initiators in terms of: (1) accumulation of cholesterol linoleate ester hydroperoxides, (2) depletion of alpha-tocopherol and beta-carotene, and (3) changes in intrinsic tryptophan fluorescence. EGb 761 afforded protection against oxidative damage in all the systems we analyzed; thus, it is an efficient scavenger of peroxyl radicals. This result extends the oxygen radical scavenging properties of the extract and supports the hypothesis of an antioxidant therapeutic action of EGb 761. PMID:7786306

  15. Scavenging of hydroxyl radical by catecholamines.

    PubMed

    Kładna, Aleksandra; Berczyński, Paweł; Kruk, Irena; Michalska, Teresa; Aboul-Enein, Hassan Y

    2012-01-01

    The direct effects of the four catecholamines (CATs), adrenaline (A), noradrenaline (NA), dopamine (D) and isoproterenol (I), on free radicals were investigated using the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH(•)) and hydroxyl radial (HO(•)). The CATs examined were found to inhibit the ESR signal intensity of DPPH(•) in a dose-dependent manner over the range 0.1-2.5 mmol/L in the following order: NA > A > I > D, with IC50= 0.30 ± 0.03 for noradrenaline and IC50= 0.86 ± 0.02 for dopamine. Hydroxyl radicals were produced using a Fenton reaction in the presence of the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO), and ESR technique was applied to detect the CATs reactivity toward the radicals. The reaction rates constant (k(r)) of CATs with HO(•) were found to be in the order of 10(9)  L/mol/s, and the k(r) value for noradrenaline was the highest (k(r)= 8.4 × 10(9)  L/mol/s). The CATs examined exhibited also a strong decrease in the light emission (62-73% at 1 mmol/L concentration and 79-89% at 2 mmol/L concentration) from a Fenton-like reaction. These reactions may be relevant to the biological action of these important polyphenolic compounds. PMID:22238226

  16. In vitro free radical scavenging activity of platinum nanoparticles

    NASA Astrophysics Data System (ADS)

    Watanabe, Aki; Kajita, Masashi; Kim, Juewon; Kanayama, Atsuhiro; Takahashi, Kyoko; Mashino, Tadahiko; Miyamoto, Yusei

    2009-11-01

    A polyacrylic acid (PAA)-protected platinum nanoparticle species (PAA-Pt) was prepared by alcohol reduction of hexachloroplatinate. The PAA-Pt nanoparticles were well dispersed and homogeneous in size with an average diameter of 2.0 ± 0.4 nm (n = 200). We used electron spin resonance to quantify the residual peroxyl radical (\\mathrm {AOO}^{\\bullet } ) generated from 2,2-azobis (2-aminopropane) dihydrochloride (AAPH) by thermal decomposition in the presence of O2 and a spectrophotometric method to quantify the residual 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. PAA-Pt scavenged these two radicals in a dose-dependent manner. Platinum was the functional component. PAA-Pt reduced the rate of oxygen consumption required for linoleic acid peroxidation initiated by \\mathrm {AOO}^{\\bullet } generated from AAPH, indicating inhibition of the propagation of linolate peroxidation. A thiobarbituric acid test also revealed dose-dependent inhibition of the linolate peroxidation by PAA-Pt. Fifty micromolar platinum, as PAA-Pt, completely quenched 250 µM DPPH radical for 5 min. Even when twice diluted in half, the PAA-Pt still quenched 100% of the 250 µM DPPH radical. The scavenging activity of PAA-Pt is durable. These observations suggest that PAA-Pt is an efficient scavenger of free radicals.

  17. Free Radical Scavenging Activity of Scoparia dulcis Extract.

    PubMed

    Babincová, M.; Sourivong, P.

    2001-01-01

    We studied the scavenging capabilities of an extract of Scoparia dulcis (a cosmopolitan weed widespread in Laos and Vietnam) for 1-diphenyl-2-picrylhydrazyl and measured hemoglobin-catalyzed linoleic acid peroxidation with an oxygen electrode. Our results demonstrated strong antioxidant activity corresponding to mitigation of the generation of hydroxyl radicals, a possible rationale for the observed therapeutic effects of this weed. PMID:12639412

  18. Calixtyrosol: a Novel Calixarene Based Potent Radical Scavenger

    PubMed Central

    Nasuhi Pur, Fazel; Akbari Dilmaghani, Karim

    2015-01-01

    The oxidative stress causes many diseases in human, therefore antioxidants have a special position in the medicinal chemistry. Tyrosol is an important antioxidant with a plenty of biological properties. There are many strategies such as clustering single drug units in order to develop new drugs. The cluster effect can increase drug effects relative to single drug unit. Calixtyrosol is the novel cluster of tyrosol that shows a more effective antioxidant activity than single tyrosol. In fact, tyrosol can be considered as 1/4 of the cluster. Four hydroxyethyl moieties have been grafted at the upper rim of the calix[4]arene in all-syn orientation, giving novel agent in the field of antioxidant agents. Free radical scavenging tests were determined by the 2, 2-diphenyl-1-picrylhydrazyl radical in methanol for four antioxidants: calixtyrosol, tyrosol, hydroxytyrosol and 3, 5-di-tert-buty l-4-hydroxytoluene to compare their antioxidant activity. Free radical scavenging test showed that calixtyrosol has enhanced antioxidant activity in comparison to the corresponding single tyrosol unit (> 5 fold), it has even more active than the other test antioxidants (2 fold). Presumably, it is attributed to tethering and arraying of four impacted tyrosol units, which make a synergistic effect in interactions with radicals for creating effective radical scavenging activity. This method is in debt of synergistic effect, tethering and arraying of single units in the cluster structure. PMID:26664385

  19. Calixtyrosol: a Novel Calixarene Based Potent Radical Scavenger.

    PubMed

    Nasuhi Pur, Fazel; Akbari Dilmaghani, Karim

    2015-01-01

    The oxidative stress causes many diseases in human, therefore antioxidants have a special position in the medicinal chemistry. Tyrosol is an important antioxidant with a plenty of biological properties. There are many strategies such as clustering single drug units in order to develop new drugs. The cluster effect can increase drug effects relative to single drug unit. Calixtyrosol is the novel cluster of tyrosol that shows a more effective antioxidant activity than single tyrosol. In fact, tyrosol can be considered as 1/4 of the cluster. Four hydroxyethyl moieties have been grafted at the upper rim of the calix[4]arene in all-syn orientation, giving novel agent in the field of antioxidant agents. Free radical scavenging tests were determined by the 2, 2-diphenyl-1-picrylhydrazyl radical in methanol for four antioxidants: calixtyrosol, tyrosol, hydroxytyrosol and 3, 5-di-tert-buty l-4-hydroxytoluene to compare their antioxidant activity. Free radical scavenging test showed that calixtyrosol has enhanced antioxidant activity in comparison to the corresponding single tyrosol unit (> 5 fold), it has even more active than the other test antioxidants (2 fold). Presumably, it is attributed to tethering and arraying of four impacted tyrosol units, which make a synergistic effect in interactions with radicals for creating effective radical scavenging activity. This method is in debt of synergistic effect, tethering and arraying of single units in the cluster structure. PMID:26664385

  20. Dual high-resolution α-glucosidase and radical scavenging profiling combined with HPLC-HRMS-SPE-NMR for identification of minor and major constituents directly from the crude extract of Pueraria lobata.

    PubMed

    Liu, Bingrui; Kongstad, Kenneth T; Qinglei, Sun; Nyberg, Nils T; Jäger, Anna K; Staerk, Dan

    2015-02-27

    The crude methanol extract of Pueraria lobata was investigated by dual high-resolution α-glucosidase inhibition and radical scavenging profiling combined with hyphenated HPLC-HRMS-SPE-NMR. Direct analysis of the crude extract without preceding purification was facilitated by combining chromatograms from two analytical-scale HPLC separations of 120 and 600 μg on-column, respectively. High-resolution α-glucosidase and radical scavenging profiles were obtained after microfractionation of the eluate in 96-well microplates. This allowed full bioactivity profiling of individual peaks in the HPLC chromatogram of the crude methanol extract. Subsequent HPLC-HRMS-SPE-NMR analysis allowed identification of 21 known compounds in addition to two new compounds, i.e., 3'-methoxydaidzein 8-C-[α-D-apiofuranosyl-(1→6)]-β-D-glucopyranoside and 6″-O-malonyl-3'-methoxydaidzin, as well as an unstable compound tentatively identified as 3'-de-O-methylpuerariafuran. PMID:25679337

  1. Production and Scavenging Mechanism of OH Radical in Atmospheric Water Droplets and Natural Water

    NASA Astrophysics Data System (ADS)

    Sakugawa, H.; Arakaki, T.; Takeda, K.; Nakatani, N.; Miyake, T.; Takedoi, H.; Masuda, N.; Hashimoto, N.

    2001-12-01

    Photochemical production rate of liquid phase OH radical was measured by irradiation of artificial sunlight to water samples and then trapping of generated OH radical to benzene followed by HPLC determination of phenol, which was generated by the reaction of OH radical with benzene. Scavenging rate was also determined by similar manner through the reaction of benzene with the radical. Analytical instrument, which automatically determines the production or scavenging rate of liquid phase OH radical, was developed in this study. Four water samples per hour can be subject to the analysis using this analyzer. Using the auto analyzer of OH radical, we determined production and scavenging rates of OH radical in rain, dew, drinking water and river waters in Hiroshima Prefecture and the Seto Inland Sea waters, western Japan. Photochemical production rate of OH radical was 1 nM/h to hundreds nM/h (for summer time noon condition at 34 \\deg N) for rain, dew (formed on Teflon sheet), drinking water (natural mineral water) and seawater, whereas the rate was μ M/h levels for dew (formed on pine tree needles), river and drinking water (tap water). Major producer of aqueous OH radical was found to be fluorescent organic matter, nitrite, nitrate, and hypochlorite. Fluorescent organic matter that is composed of yet uncharacterized number of organic compounds contributed to most of OH production in rain, river and seawaters studied whereas nitrite, nitrate and hypochlorite were major contributors (ave. 99, 83 and 99%) for the radical production in dew, natural mineral water and tap water, respectively. Scavenging rate constant of OH radical in rain and dew was also estimated to be the order of 105/s and thus the lifetime of OH radical was in the order of microseconds. Assuming all the OH radicals were generated by aqueous photochemical reactions, the steady state concentration of OH radical in rain and dew was about 1\\times10-15M for both rain and dew waters. Major sink of OH

  2. Free radical scavengers in anaesthesiology and critical care

    PubMed Central

    Hatwalne, Milind S

    2012-01-01

    Free radicals are highly reactive and unstable compounds. These highly reactive molecules cause oxidative damage to cellular components such as DNA, proteins and lipids. They play central role in the mechanism of cell injury and cell death. Free radical scavengers either prevent these reactive species from being formed, or remove them before they can damage vital components of the cell. Oxidative stress defines an imbalance in production of oxidizing chemical species and their effective removal by protective antioxidants and scavenger enzymes. Evidence of massive oxidative stress is well established in critical illnesses characterized by tissue ischaemia-reperfusion injury and by an intense systemic inflammatory response such as during sepsis and acute respiratory distress syndrome, acute lung injury. Several clinical trials have been performed in order to reduce oxidative stress by supplementation of antioxidants alone or in combination with standard therapies. Antioxidant supplementation at an early stage of illness may lead to improved therapies in the treatment of critically ill patients. Several intravenous anaesthetic drugs act as reactive oxygen species scavengers. Anaesthetic preconditioning is of particular interest to anaesthesiologist, in which lasting protection of myocardium is elicited by brief exposure to a inhalational anaesthetic agent. These anasthetics may also mediate protective effects in other organs, such as the brain and kidney It is important for the anaesthesiologist to understand the mechanism of damage caused by free radicals and how free radical scavengers work so that this knowledge can be applied to varied pathological conditions. The topic was hand searched in text books and electronically searched from PubMed and Google scholar using text words. PMID:22923819

  3. Free radical scavengers in anaesthesiology and critical care.

    PubMed

    Hatwalne, Milind S

    2012-05-01

    Free radicals are highly reactive and unstable compounds. These highly reactive molecules cause oxidative damage to cellular components such as DNA, proteins and lipids. They play central role in the mechanism of cell injury and cell death. Free radical scavengers either prevent these reactive species from being formed, or remove them before they can damage vital components of the cell. Oxidative stress defines an imbalance in production of oxidizing chemical species and their effective removal by protective antioxidants and scavenger enzymes. Evidence of massive oxidative stress is well established in critical illnesses characterized by tissue ischaemia-reperfusion injury and by an intense systemic inflammatory response such as during sepsis and acute respiratory distress syndrome, acute lung injury. Several clinical trials have been performed in order to reduce oxidative stress by supplementation of antioxidants alone or in combination with standard therapies. Antioxidant supplementation at an early stage of illness may lead to improved therapies in the treatment of critically ill patients. Several intravenous anaesthetic drugs act as reactive oxygen species scavengers. Anaesthetic preconditioning is of particular interest to anaesthesiologist, in which lasting protection of myocardium is elicited by brief exposure to a inhalational anaesthetic agent. These anasthetics may also mediate protective effects in other organs, such as the brain and kidney It is important for the anaesthesiologist to understand the mechanism of damage caused by free radicals and how free radical scavengers work so that this knowledge can be applied to varied pathological conditions. The topic was hand searched in text books and electronically searched from PubMed and Google scholar using text words. PMID:22923819

  4. Antioxidant and free radical scavenging activities of some fruits.

    PubMed

    Prakash, Dhan; Upadhyay, Garima; Pushpangadan, P; Gupta, Charu

    2011-01-01

    Phenols, a major group of antioxidant phytochemicals, have profound importance due to their biological and free radical scavenging activities. To identify their potential sources extracts of some fruits and their different parts were studied for total phenolic contents (TPC), antioxidant (AOA) and free radical scavenging activities (FRSA). The amount of TPC varied from 10.5 (Carissa carandus, fruit peel) to 343.2 mg/g (Caesalpinia Mexicana, fruits) and AOA from 20.3% (Musa paradisiacal, fruits) to 96.7% (Caesalpinia Mexicana, fruits). Fruits of Caesalpinia Mexicana, Acacia auriculiformis, fruit pericarp green fibres of Cocus nucifera, and fruits of Emblica officinalis were found to have high TPC (73.1-343.2 mg/g) and high AOA (68.5-96.7%). Promising fruits were studied for their FRSA and reducing power (RP) measured by DPPH assay where the fruits of Caesalpinia mexicana, fruit pericarp fibres of Cocus nucifera, fruits of Emblica officinalis showed very low IC50 ranging from 0.009 to 0.016 mg/ml, EC50 from 0.39 to 0.70 mg/mg DPPH and reasonably high values (142.1-256.3) of anti radical power (ARP), indicating their strong FRSA and reducing power (RP) as evident by their low ASE/ml values (0.42-1.08). They also showed better inhibition of lipid peroxidation measured by using ferric thiocyanate assay and by using egg yolk compared to the reference standard quercetin. The ferrous and ferric ion chelating capacity of the promising fruits and their underutilized parts in terms of IC50 varied from 0.12 (Emblica officinalis, fruits) to 2.44 mg/ml (Mangifera indica, Seed kernel) and 0.22 (Caesalpinia Mexicana, fruits) to 2.59 mg/ml (Litchi chinensis, fruit peel) respectively. Fruit pulp, peel and seeds of Litchi chinensis with reasonable amount of phenols (48.3, 43.9, 50.1 mg/ml) showed low ARP (23.5, 38.3, 33.8) and ASE/ml (3.13, 2.18, 2.62) respectively in contrast to Aegle marmelos with comparatively lower phenols (35.1 mg/g) exhibited good ARP (57.4) and RP (1.67 ASE

  5. Phytochemical Analysis and Free Radical Scavenging Activity of Medicinal Plants Gnidia glauca and Dioscorea bulbifera

    PubMed Central

    Ghosh, Sougata; Derle, Abhishek; Ahire, Mehul; More, Piyush; Jagtap, Soham; Phadatare, Suvarna D.; Patil, Ajay B.; Jabgunde, Amit M.; Sharma, Geeta K.; Shinde, Vaishali S.; Pardesi, Karishma; Dhavale, Dilip D.; Chopade, Balu A.

    2013-01-01

    Gnidia glauca and Dioscorea bulbifera are traditional medicinal plants that can be considered as sources of natural antioxidants. Herein we report the phytochemical analysis and free radical scavenging activity of their sequential extracts. Phenolic and flavonoid content were determined. Scavenging activity was checked against pulse radiolysis generated ABTS•+ and OH radical, in addition to DPPH, superoxide and hydroxyl radicals by biochemical methods followed by principal component analysis. G. glauca leaf extracts were rich in phenolic and flavonoid content. Ethyl acetate extract of D. bulbifera bulbs and methanol extract of G. glauca stem exhibited excellent scavenging of pulse radiolysis generated ABTS•+ radical with a second order rate constant of 2.33×106 and 1.72×106, respectively. Similarly, methanol extract of G. glauca flower and ethyl acetate extract of D. bulbifera bulb with second order rate constants of 4.48×106 and 4.46×106 were found to be potent scavengers of pulse radiolysis generated OH radical. G. glauca leaf and stem showed excellent reducing activity and free radical scavenging activity. HPTLC fingerprinting, carried out in mobile phase, chloroform: toluene: ethanol (4: 4: 1, v/v) showed presence of florescent compound at 366 nm as well as UV active compound at 254 nm. GC-TOF-MS analysis revealed the predominance of diphenyl sulfone as major compound in G. glauca. Significant levels of n-hexadecanoic acid and octadecanoic acid were also present. Diosgenin (C27H42O3) and diosgenin (3á,25R) acetate were present as major phytoconstituents in the extracts of D. bulbifera. G. glauca and D. bulbifera contain significant amounts of phytochemicals with antioxidative properties that can be exploited as a potential source for herbal remedy for oxidative stress induced diseases. These results rationalize further investigation in the potential discovery of new natural bioactive principles from these two important medicinal plants. PMID:24367520

  6. Effect of Heating on DPPH Radical Scavenging Activity of Meat Substitute

    PubMed Central

    Song, Hyeun Sung; Bae, Jun Kyu; Park, Inshik

    2013-01-01

    This study was conducted to evaluate the increase of DPPH radical scavenging activity of meat substitute by heating. The meat substitute showed higher DPPH radical scavenging activity than those of other foods rich in protein such as beef, pork, chicken, and soybean curd. The DPPH radical scavenging activity of meat substitute was dependent upon concentration, heating temperature and heating time of meat substitute. The DPPH radical scavenging activity of meat substitute was enhanced with increasing heating temperature and time. The increase of DPPH radical scavenging activity was only applied to meat substitute without showing any activation in other foods rich in protein such as beef, pork, chicken, and soybean curd. PMID:24471114

  7. Potent Radical-Scavenging Activities of Thiamin and Thiamin Diphosphate

    PubMed Central

    Okai, Yasuji; Higashi-Okai, Kiyoka; F. Sato, Eisuke; Konaka, Ryusei; Inoue, Masayasu

    2007-01-01

    Various radical-scavenging activities of thiamin and thiamin diphosphate (TDP) were found in some in vitro experiments. Thiamin and TDP caused considerable suppressive effects on superoxide generation in hypoxanthine and xanthine oxidase system which was measured by a sensitive chemiluminescence method using 2-methyl-6-[p-methylphenyl]-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA), and their 50% inhibition (IC50) values were estimated to be 158 and 56 µM, respectively. They also showed the significant suppression against hydroperoxide generation derived from oxidized linoleic acid which was estimated by aluminum chloride method and their IC50 values were calculated to be 260 and 46 µM. They further prevented the oxygen radical generation in opsonized zymosan-stimulated human blood neutrophils which was shown by chemiluminescence method using luminol, and their IC50 values were calculated to be 169 and 38 µM. In contrast, they caused weak but significantly suppressive effects on the hydroxyl radical generation by Fenton reaction which was measured by electric spin resonance (ESR) method, their IC50 values were calculated to be 8.45 and 1.46 mM respectively. These results strongly suggest a possibility that thiamin and TDP play as radical scavengers in cell-free and cellular systems. PMID:18437212

  8. Antioxidant and free radical scavenging activity of Spondias pinnata

    PubMed Central

    Hazra, Bibhabasu; Biswas, Santanu; Mandal, Nripendranath

    2008-01-01

    Background Many diseases are associated with oxidative stress caused by free radicals. Current research is directed towards finding naturally-occurring antioxidants of plant origin. The aim of the present study was to evaluate the in vitro antioxidant activities of Spondias pinnata stem bark extract. Methods A 70% methanol extract of Spondias pinnata stem bark was studied in vitro for total antioxidant activity, for scavenging of hydroxyl radicals, superoxide anions, nitric oxide, hydrogen peroxide, peroxynitrite, singlet oxygen and hypochlorous acid, and for iron chelating capacity, reducing power, and phenolic and flavonoid contents. Results The extract showed total antioxidant activity with a trolox equivalent antioxidant concentration (TEAC) value of 0.78 ± 0.02. The IC50 values for scavenging of free radicals were 112.18 ± 3.27 μg/ml, 13.46 ± 0.66 μg/ml and 24.48 ± 2.31 μg/ml for hydroxyl, superoxide and nitric oxide, respectively. The IC50 for hydrogen peroxide scavenging was 44.74 ± 25.61 mg/ml. For the peroxynitrite, singlet oxygen and hypochlorous acid scavenging activities the IC50 values were 716.32 ± 32.25 μg/ml, 58.07 ± 5.36 μg/ml and 127.99 ± 6.26 μg/ml, respectively. The extract was found to be a potent iron chelator with IC50 = 66.54 ± 0.84 μg/ml. The reducing power was increased with increasing amounts of extract. The plant extract (100 mg) yielded 91.47 ± 0.004 mg/ml gallic acid-equivalent phenolic content and 350.5 ± 0.004 mg/ml quercetin-equivalent flavonoid content. Conclusion The present study provides evidence that a 70% methanol extract of Spondias pinnata stem bark is a potential source of natural antioxidants. PMID:19068130

  9. Radical scavenging activity and cytotoxicity of ferulic acid.

    PubMed

    Ogiwara, Takako; Satoh, Kazue; Kadoma, Yoshinori; Murakami, Yukio; Unten, Senwa; Atsumi, Toshiko; Sakagami, Hiroshi; Fujisawa, Seiichiro

    2002-01-01

    Ferulic acid and eugenol were examined for their superoxide (O2-), hydroxyl radical (.OH) and nitric oxide (NO)-scavenging ability, using ESR spectroscopy with spin trap agents DMPO and carboxy-PTIO/NOC-7. Ferulic acid more efficiently scavenged .OH and NO than eugenol. The O2- scavenging activity of ferulic acid was comparable with that of eugenol. Ferulic acid significantly reduced the NO production by lipopolysaccharide (LPS)-stimulated mouse macrophage-like cells (Raw 264.7 cells) compared to eugenol. The cytotoxic activity of ferulic acid against Raw 264.7 cells was comparable with that against human submandibular gland carcinoma (HSG) cells and the cytotoxicity of ferulic acid was about 10-fold smaller than that of eugenol. The stoichiometric factor (n) (number of moles of peroxy radical trapped by moles of the relevant phenol) of ferulic acid and eugenol was investigated, using the induction period methods of the methyl methacrylate polymerization system. The n-value of ferulic acid (1.5) was higher than that of eugenol (1.0) and was similar to that of 2, 6-di-t-butyl-4-methylphenol (BHT). Ferulic acid as well as eugenol may produce a dimer during the induction period due to an n-value less than 2. These results suggested that ferulic acid may be useful for preventing cell damage perhaps caused by O2-, and in particular by .OH and NO, in living systems. PMID:12529986

  10. Cytotoxic and radical scavenging activity of blended herbal extracts.

    PubMed

    Nemoto, Yukio; Satoh, Kazue; Toriizuka, Kazuo; Hirai, Yasuaki; Tobe, Takashi; Sakagami, Hiroshi; Nakashima, Hideki; Ida, Yoshiteru

    2002-01-01

    Chinese medicines have been applied to a variety of diseases producing various favorable effects, possibly due to the interactions between individual components. Establishment of an evaluation method for such interactions may facilitate the production of new natural medicines. We investigated here the interaction of the hot water extract of Aconiti Tuber (one of the most prominent Chinese medicines) and that of Scutellariae Radix, Coptidis Rhizoma, Glycyrrhizae Radix, Atractylodesi, Lanceae Rhizoma or Poria, by measuring the superoxide anion (O2-), hydroxyl radical (OH) and nitric oxide (NO) scavenging activity, using ESR spectroscopy. We found that a 1:1 mixture of the hot water extract of one herb and that of another herb (referred to as a combined formula) showed a higher radical scavenging activity and cytotoxic activity than the hot water extract of a 1:1 mixture of two herbs (referred to as a blended formula). Both formulae showed higher cytotoxic activity against human oral tumor cell lines than against normal cells. These data further confirm the medicinal usefulness of combinations of empirical Chinese medicines. PMID:12494872

  11. Radical scavenging ability of some compounds isolated from Piper cubeba towards free radicals.

    PubMed

    Aboul-Enein, Hassan Y; Kładna, Aleksandra; Kruk, Irena

    2011-01-01

    The purpose of this study was to identify the antioxidant activity of 16 compounds isolated from Piper cubeba (CNCs) through the extent of their capacities to scavenge free radicals, hydroxyl radical (HO(•)), superoxide anion radical O•(2)(-) and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(•)), in different systems. Electron paramagnetic resonance (EPR) and 5,5-dimethyl-1-pyrroline-N-oxide, DMPO, as the spin trap, and chemiluminescence techniques were applied. Using the Fenton-like reaction [Fe(II) + H(2)O(2)], CNCs were found to inhibit DMPO-OH radical formation ranging from 5 to 57% at 1.25 mmol L(-1) concentration. The examined CNCs also showed a high DPPH antiradical activity (ranging from 15 to 99% at 5 mmol L(-1) concentration). Furthermore, the results indicated that seven of the 16 tested compounds may catalyse the conversion of superoxide radicals generated in the potassium superoxide/18-crown-6 ether system, thus showing superoxide dismutase-like activity. The data obtained suggest that radical scavenging properties of CNCs might have potential application in many plant medicines. PMID:21681910

  12. Changes in free-radical scavenging ability of kombucha tea during fermentation.

    PubMed

    Jayabalan, R; Subathradevi, P; Marimuthu, S; Sathishkumar, M; Swaminathan, K

    2008-07-01

    Kombucha tea is a fermented tea beverage produced by fermenting sugared black tea with tea fungus (kombucha). Free-radical scavenging abilities of kombucha tea prepared from green tea (GTK), black tea (BTK) and tea waste material (TWK) along with pH, phenolic compounds and reducing power were investigated during fermentation period. Phenolic compounds, scavenging activity on DPPH radical, superoxide radical (xanthine-xanthine oxidase system) and inhibitory activity against hydroxyl radical mediated linoleic acid oxidation (ammonium thiocyanate assay) were increased during fermentation period, whereas pH, reducing power, hydroxyl radical scavenging ability (ascorbic acid-iron EDTA) and anti-lipid peroxidation ability (thiobarbituric assay) were decreased. From the present study, it is obvious that there might be some chances of structural modification of components in tea due to enzymes liberated by bacteria and yeast during kombucha fermentation which results in better scavenging performance on nitrogen and superoxide radicals, and poor scavenging performance on hydroxyl radicals. PMID:26054285

  13. In vitro radical scavenging activity of two Columbian Magnoliaceae

    NASA Astrophysics Data System (ADS)

    Puertas M., Miguel A.; Mesa v., Ana M.; Sáez v., Jairo A.

    2005-08-01

    The recent interest in the conservation of the tropical forest is due, at least in part, to the potential economic and health benefits that can be exploited from several plants. This report shows the in vitro antioxidant activity of some fractions isolated from leaves of two Columbian Magnoliaceae, Talauma hernandezii G. Lozano-C and Dugandiodendron yarumalense Lozano. The activity was determined using the radical monocation 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS·+) and the stable free radical 2-2-diphenyl-1-picrylhydrazyl (DPPH·), as part of general biological screening of these plants. The antioxidant capacity obtained from fractions was similar to those of α-tocopherol, tert-butylated hydroxyanisole (BHA), and ascorbic acid. The most active scavenger extract was the fraction 7 (TAA = 48.6 mmol Trolox/kg extract and IC50 ≤ 0.01 kg extract/mmol DPPH); and the least active was the fraction 1 (TAA = 11.23 mmol Trolox/kg extract and IC50 = 0.21 kg extract/mmol DPPH) all of them isolated from D. yarumalense. These results suggest that these plants can be attractive as source of antioxidant compounds with the ability to reduce radicals like ATBS and DPPH.

  14. Isolation and structure elucidation of radical scavengers from Thymus vulgaris leaves.

    PubMed

    Dapkevicius, Airidas; van Beek, Teris A; Lelyveld, Gerrit P; van Veldhuizen, Albertus; de Groot, Aede; Linssen, Jozef P H; Venskutonis, Rimantas

    2002-06-01

    2,2-Diphenyl-1-picrylhydrazyl radical (DPPH*) scavenging activity-guided fractionation of a leaf extract of Thymus vulgaris led to the isolation of the radical scavengers rosmarinic acid 1, eriodictyol, taxifolin, luteolin 7-glucuronide, p-cymene 2,3-diol, p-cymene 2,3-diol 6-6'-dimer, carvacrol, thymol, and a new compound, 2. The fractionation was considerably facilitated by using an on-line HPLC detector for radical scavenging activity. In this detector activity is monitored as the disappearance of the color of a postcolumn added stable radical after reacting with radical scavengers in a reaction coil. Compound 2, which consists of rosmarinic and caffeic acid moieties linked via a C-3'-C-8' ' ether bridge, was mainly elucidated by various NMR techniques and CD. Phenylpropanoid trimer 2 was a weaker and stronger radical scavenger than rosmarinic acid 1 in off-line TEAC and DPPH* assays, respectively. PMID:12088434

  15. PEGylated Nanoceria as Radical Scavenger with Tunable Redox Chemistry

    SciTech Connect

    Karakoti, Ajay S.; Singh, Sanjay; Kumar, Amit; Malinska, M.; Kuchibhatla, Satyanarayana V N T; Wozniak, K.; Self, William; Seal, Sudipta

    2009-10-14

    Cerium oxide nanoparticles (CNPs) have shown tremendous potential in various applications such as water gas shift catalysis, chemical mechanical planarization (CMP), solid oxide fuel cells (SOFC), solar cells4 and high temperature oxidation protection coatings1. Recently, CNPs have been demonstrated to protect biological tissues against radiation induced damage, scavenging of superoxide anions, prevention of laser induced retinal damage, reduction of spinal injury in a tissue culture model, prevention of cardiovascular myopathy, pH dependent antioxidant properties, as a tool for immunoassays as well as other inflammatory diseases2. In most biomedical applications it is speculated that nanoceria is a regenerative radical scavenger with the ability to regenerate its active 3+ oxidation state for radical scavenging. Thus far there are no reports to control the regeneration of Ce3+ oxidation state which is the most important parameter in the application of CNPs as a reliable and regenerative radical scavenger. Thus, there is an imminent need to increase the potency of CNPs to achieve higher degree of protection against reactive oxygen species (ROS), to increase the residence time of CNPs in body and to control the regeneration of 3+ oxidation state. PEG has been reported to increase the residence time of nanoparticles and proteins inside cells and provide biocompatibility3. PEGylated counterparts of the SOD enzymes have shown improved performance over non-PEGylated enzymes. Herein, we report our efforts to synthesize CNPs directly in polyethylene glycol (mol wt 600) solution and determine the effect of increasing concentration of PEG (PEG vol % as 5, 10, 20, 40, 60 and 80) on the SOD mimetic properties exhibited by nanoceria. We also report how the active Ce3+ oxidation state can be regenerated or further tuned to regenerate at faster rate. We further demonstrate the role of PEG on the redox chemistry of CNPs catalyzed by hydrogen peroxide. Several complexes of PEGs

  16. Investigation of the free radical scavenging activity of Ginkgo biloba L. leaves.

    PubMed

    Ellnain-Wojtaszek, M; Kruczyński, Z; Kasprzak, J

    2003-02-01

    The free radical scavenging activity of methanolic, ethanolic and aqueous extracts from Ginkgo biloba leaves, has been determined by EPR (electron paramagnetic resonance) using the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging method. The investigation has also included selected constituents of G. biloba leaves, protocatechuic and p-coumaric acids, quercetin, rutin, isoginkgetin and (+)-catechin. PMID:12628386

  17. Hydroxyl radical (OH) scavenging in young and mature landfill leachates.

    PubMed

    Ghazi, Niloufar M; Lastra, Andres A; Watts, Michael J

    2014-06-01

    The final discharge point for collected landfill leachates is frequently the local municipal wastewater treatment facility. The salinity, color, nutrient, and anthropogenic organics contamination of leachates often necessitate some form of pre-treatment. When advanced oxidation processes (AOPs) are considered for pre-treatment, the unique composition of dissolved organic matter (DOM) and the relatively high concentrations of some inorganic solutes in leachate will inhibit treatment efficiency. The most important benchmark for design of AOPs is the expected steady-state production of free radical (OH). Without a quantitative assessment of total OH consumption in high-strength waste water, like a landfill leachate, efficient AOP treatment is uncertain. For this reason, two landfill leachates, distinct in color, DOM, and age of landfill, were characterized for OH-scavenging using an established competition kinetics method. After stripping the samples of inorganic carbon, the DOM in leachate from mature (stabilized) landfill was found to react with OH at a rate of 9.76 × 10(8) M(-1)s(-1). However, DOM in leachate from newer landfill was observed to scavenge available OH at a faster rate (8.28 × 10(9) M(-1)s(-1)). The combination of fast rate of reaction with OH and abundance of DOM in the sampled leachate severely limited the contribution of OH to degradation of an O3- and OH-labile organic probe compound (bisphenol-a) in oxidized mature leachate (fOH = 0.03). Substantial dosing of both O3 and H2O2 (>70 mg/L and >24 mg/L, respectively) may be required to see at least 1-log-removal (>90%) of an OH-selective leachate contaminant (i.e., parachlorobenzoic acid) in a mature landfill leachate. PMID:24675270

  18. Investigation of gold nanoparticle radiosensitization mechanisms using a free radical scavenger and protons of different energies.

    PubMed

    Jeynes, J C G; Merchant, M J; Spindler, A; Wera, A-C; Kirkby, K J

    2014-11-01

    Gold nanoparticles (GNPs) have been shown to sensitize cancer cells to x-ray radiation, particularly at kV energies where photoelectric interactions dominate and the high atomic number of gold makes a large difference to x-ray absorption. Protons have a high cross-section for gold at a large range of relevant clinical energies, and so potentially could be used with GNPs for increased therapeutic effect.Here, we investigate the contribution of secondary electron emission to cancer cell radiosensitization and investigate how this parameter is affected by proton energy and a free radical scavenger. We simulate the emission from a realistic cell phantom containing GNPs after traversal by protons and x-rays with different energies. We find that with a range of proton energies (1-250 MeV) there is a small increase in secondaries compared to a much larger increase with x-rays. Secondary electrons are known to produce toxic free radicals. Using a cancer cell line in vitro we find that a free radical scavenger has no protective effect on cells containing GNPs irradiated with 3 MeV protons, while it does protect against cells irradiated with x-rays. We conclude that GNP generated free radicals are a major cause of radiosensitization and that there is likely to be much less dose enhancement effect with clinical proton beams compared to x-rays. PMID:25296027

  19. Investigation of gold nanoparticle radiosensitization mechanisms using a free radical scavenger and protons of different energies

    NASA Astrophysics Data System (ADS)

    Jeynes, J. C. G.; Merchant, M. J.; Spindler, A.; Wera, A.-C.; Kirkby, K. J.

    2014-10-01

    Gold nanoparticles (GNPs) have been shown to sensitize cancer cells to x-ray radiation, particularly at kV energies where photoelectric interactions dominate and the high atomic number of gold makes a large difference to x-ray absorption. Protons have a high cross-section for gold at a large range of relevant clinical energies, and so potentially could be used with GNPs for increased therapeutic effect. Here, we investigate the contribution of secondary electron emission to cancer cell radiosensitization and investigate how this parameter is affected by proton energy and a free radical scavenger. We simulate the emission from a realistic cell phantom containing GNPs after traversal by protons and x-rays with different energies. We find that with a range of proton energies (1-250 MeV) there is a small increase in secondaries compared to a much larger increase with x-rays. Secondary electrons are known to produce toxic free radicals. Using a cancer cell line in vitro we find that a free radical scavenger has no protective effect on cells containing GNPs irradiated with 3 MeV protons, while it does protect against cells irradiated with x-rays. We conclude that GNP generated free radicals are a major cause of radiosensitization and that there is likely to be much less dose enhancement effect with clinical proton beams compared to x-rays.

  20. Study on the free radical scavenging activity of sea cucumber (Paracaudina chinens var.) gelatin hydrolysate

    NASA Astrophysics Data System (ADS)

    Zeng, Mingyong; Xiao, Feng; Zhao, Yuanhui; Liu, Zunying; Li, Bafang; Dong, Shiyuan

    2007-07-01

    Gelatin from the sea cucumber (Paracaudina chinens var.) was hydrolyzed by bromelain and the hydrolysate was found to have a high free radical scavenging activity. The hydrolysate was fractionated through an ultrafiltration membrane with 5 kDa molecular weight cutoff (MWCO). The portion (less than 5 kDa) was further separated by Sephadex G-25. The active peak was collected and assayed for free radical scavenging activity. The scavenging rates for superoxide anion radicals (O2·-) and hydroxyl radicals (·OH) of the fraction with the highest activity were 29.02% and 75.41%, respectively. A rabbit liver mitochondrial free radical damage model was adopted to study the free radical scavenging activity of the fraction. The results showed that the sea cucumber gelatin hydrolysate can prevent the damage of rabbit liver and mitochondria.

  1. Studies on free radical scavenging activity in Chinese seaweeds part I. Screening results

    NASA Astrophysics Data System (ADS)

    Yan, Xiao-Jun; Fang, Guo-Ming; Lou, Qing-Xiang

    1999-09-01

    Antioxidants have attracted the attention of researchers due to their beneficial effects as free radical scavengers. Application of a stable free radical named 1, 1-diphenyl-2-picrylhydrazyl(DPPH) to screen the free radical scavenging activity in 27 species of Chinese seaweed showed that 15 of them had significant activity in at least one of the organic solvent extracts. The most interesting seaweed species were Gelidium amansii, Gloiosiphonia capillaris, Polysiphonia urceolata, Sargassum kjellmanianum, Desmarestia viridis, and Rhodomela teres.

  2. 1,1-Diphenyl-2-picrylhydrazyl radical and superoxide anion scavenging activity of Rhizophora mangle (L.) bark

    PubMed Central

    Sánchez, Janet Calero; García, Roberto Faure; Cors, Ma. Teresa Mitjavila

    2010-01-01

    Background: Rhizophora mangle (L.) produce a variety of substances that possesses pharmacological actions. Although it shown antioxidant properties in some assays, there is no available information about its effect on some free radical species. So the objective of the present research is to evaluate the DPPH radical and superoxide anion scavenging properties of R. mangle extract and its polyphenol fraction. Methods: Rhizophora mangle (L.) bark aqueous extract and its major constituent, polyphenols fraction, were investigated for their antioxidant activities employing 2 in vitro assay systems: 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide anion radicals scavenging. Results: IC50 for DPPH radical-scavenging activity was 6.7 µg tannins/mL for extract and 7.6 µg tannins/mL for polyphenolic fraction. The extract showed better activity than its fraction (P < 0.05) in the DPPH radicals reducing power. Polyphenolic fraction exhibited better superoxide anion scavenging ability (IC50 = 21.6 µg tannins/mL) than the extract (IC50 = 31.9 µg tannins/mL). Antioxidant activities of both samples increased with the rise of tannins concentration. The comparison of regression lines showed significant differences (P < 0.05) between extract and its polyphenolic fraction in both assays, indicating that extract was more effective in DPPH radical scavenging than its fraction at tannin concentrations below the crossing point of both lines, while that fraction was more effective than extract inhibiting the superoxide anions generation. Conclusions: R. mangle aqueous extract showed a potent antioxidant activity, achieved by the scavenging ability observed against DPPH radicals and superoxide anions. Regarding its polyphenolic composition, the antioxidant effects observed in this study are due, most probably, to the presence of polyphenolic compounds. PMID:21589751

  3. Radical scavenging potential of phenolics from Bryophyllum pinnatum (LAM.) OKEN.

    PubMed

    Gupta, Suneel; Banerjee, Rintu

    2011-01-01

    Optimization of the extraction process of phenolics from Bryophyllum pinnatum was carried out using response-surface methodology (RSM). The effect of different variables such as ratio of solvents, plant material/solvent ratio, extraction time, and temperature were investigated. An optimal phenolics yield of 7.952 mg/g gallic acid equivalence (GAE) was achieved at reduced levels of methanol/water ratio (1:1, v/v). During optimization, the product yield was enhanced by ∼2-fold at reduced extraction solvent (methanol/water) up to 37%. Validation of the RSM model for extraction of total phenolic content (TPC) was confirmed by high-performance liquid chromatography (HPLC) analysis. The obtained experimental values were in good agreement with the predicted values, thereby indicating the appropriateness of the model generated. Phenolic extracts from B. pinnatum were further examined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) methods for determining the radical scavenging activities. EC(50) values of B. pinnatum extracts (BPEs) obtained by these methods were in accordance with the amount of phenolics present in the extract. Significant correlation was found between total phenolic content and antioxidant activities (p < 0.05). PMID:21660869

  4. Synthesis of dimeric phenol derivatives and determination of in vitro antioxidant and radical scavenging activities.

    PubMed

    Güllçin, Ilhami; Daştan, Arif

    2007-12-01

    In this study, di(2,6-dimethylphenol) (Di-DMP), di(2,6-diisopropylphenol) (Di-DIP, dipropofol) and di(2,6-di-t-butylphenol) (Di-DTP) were synthesized by the reaction of monomeric phenol derivatives with catalytic CuCl(OH). TMEDA and Na2S2O4. Their antioxidant capacity and radical scavenging activity were examined using different in vitro methodologies such as 1,1-diphenyl-2-picryl-hydrazyl (DPPH*) free radical scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, total antioxidant activity by ferric thiocyanate, total reducing power by potassium ferricyanide reduction method, superoxide anion radical scavenging, hydrogen peroxide scavenging and ferrous ions chelating activities. PMID:18237020

  5. Electron spin resonance measurement of radical scavenging activity of Aronia melanocarpa fruit juice

    PubMed Central

    Valcheva-Kuzmanova, Stefka; Blagović, Branka; Valić, Srećko

    2012-01-01

    Background: The fruits of Aronia melanocarpa (Michx.) Elliot contain large amounts of phenolic substances, mainly procyanidins, anthocyanins and other flavonoids, and phenolic acids. The ability of phenolic substances to act as antioxidants has been well established. Objective: In this study, we investigated the radical scavenging activity of A. melanocarpa fruit juice (AMFJ). Materials and Methods: The method used was electron spin resonance (ESR) spectroscopy. The galvinoxyl free radical was used as a scavenging object. AMFJ was added to the galvinoxyl free radical solution. The measure of the radical scavenging activity was the decrease of signal intensity. Results: AMFJ showed a potent antiradical activity causing a strong and rapid decrease of signal intensity as a function of time and juice concentration. This effect of AMFJ was probably due to the activity of its phenolic constituents. Conclusion: The ESR measurements in this study showed a pronounced radical scavenging effect of AMFJ, an important mechanism of its antioxidant activity. PMID:22701293

  6. Low molecular weight compounds with transition metals as free radical scavengers and novel therapeutic agents.

    PubMed

    Bencini, Andrea; Failli, Paola; Valtancoli, Barbara; Bani, Daniele

    2010-07-01

    Molecules able to modulate the levels of endogenous free radicals, such as reactive oxygen species (ROS) and nitric oxide (NO), are of pivotal interest for pharmacological and pharmaceutical sciences because of their potential therapeutic relevance. In fact, ROS and NO, which are normal products of cell metabolism, may play a dual beneficial/deleterious role, depending on local concentration and mode of generation. As such, they have been identified as key pathogenic factors for many inflammatory, vascular dysfunctional and degenerative disorders, including atherosclerosis, hypertension, cardiovascular and neurodegenerative diseases, cancer, diabetes mellitus, and ageing. Therefore, the identification and characterization of novel antioxidant/free radical scavenger molecules may expand the current therapeutic implements for the treatment and prevention of the above diseases. In this perspective, low molecular weight complexes of transition metals with organic scaffolds are viewed and investigated as promising pharmaceutical agents. These complexes take advantage of the known principles of inorganic chemistry, i.e. the ability of transition metals, Fe(II), Co(II), Mn(II) and Ru(II), to bind to and react with NO and/or ROS, to counterbalance excessive endogenous free radical generation in biological systems. Among NO scavengers, representative examples are iron complexes with dithiocarbamates or ruthenium compounds with polyamine-polycarboxylate scaffolds; on the other hand, manganese-based molecules appear effective as ROS scavengers. Of note, Mn(II)-containing molecules, currently under study as ROS scavengers, have major functional similarities to Mn-superoxide dismutase (SOD), a Mn-containing enzyme acting as potent endogenous anti-oxidant. In this article, we briefly summarize the state-of-the-art concerning the chemical and biological properties of transition metal ion complexes with low molecular weight synthetic ligands as ROS/NO scavengers provided with

  7. Efficient method for screening and identification of radical scavengers in the leaves of Olea europaea L.

    PubMed

    Wang, Xiaofei; Li, Chen; Liu, Yewei; Li, Hongbing; Di, Duolong

    2011-03-01

    In this article, an efficient method was developed to screen, isolate and identify the major radical scavengers in the leaves of Olea europaea L. by DPPH-HPLC-DAD, HSCCC and NMR. The method of DPPH-HPLC-DAD was used to screen the major radical scavengers. It was found that three major constituents (A, B, C) in the extract of the leaves of O. europaea L. possessed potential antioxidant activities. In order to identify the chemical structures of those compounds, the HSCCC method with a two-phase solvent system composed of petroleum ether-ethyl acetate-water at an optimized volume ratio of 6:600:700 (v/v/v) together with column chromatography was developed to isolate and purify the active compounds. Pure compounds A (225 mg), B (10 mg) and C (12 mg) with purities 92.6, 95.1 and 96.4%, respectively, were obtained from the crude sample (500 mg). Their structures were identified as oleuropein (A), luteolin-7-O-glucoside (B) and verbascoside (C) by (1) H-NMR and (13) C-NMR. PMID:21321972

  8. Free radical scavengers, vitamins A, C, and E, plus magnesium reduces noise trauma

    PubMed Central

    Le Prell, Colleen G.; Hughes, Larry F.; Miller, Josef M.

    2007-01-01

    Free radical formation in the cochlea plays a key role in the development of noise-induced hearing loss (NIHL). The amount, distribution, and time course of free radical formation have been defined, including a clinically significant formation of both reactive oxygen species and reactive nitrogen species 7–10 days following noise exposure. Reduction in cochlear blood flow as a result of free radical formation has also been described. Here we report that the antioxidant agents, vitamins A, C, and E, act in synergy with magnesium to effectively prevent noise-induced trauma. Neither the antioxidant agents nor magnesium reliably reduced NIHL or sensory cell death with the doses we used when these agents were delivered alone. In combination, however, they were highly effective in reducing both hearing loss and cell death even with treatment initiated just one hour prior to noise exposure. This study supports roles for both free radical formation and noise-induced vasoconstriction in the onset and progression of NIHL. Identification of this safe and effective antioxidant intervention that attenuates NIHL provides a compelling rationale for human trials in which free radical scavengers are used to eliminate this single major cause of acquired hearing loss. PMID:17395018

  9. Phytochemical investigation and evaluation of in vitro free radical scavenging activity of Tabernaemontana divaricata Linn.

    PubMed

    Jain, Sachin; Jain, Avijeet; Jain, Neetesh; Jain, D K; Balekar, Neelam

    2010-02-01

    We evaluate the in vitro free radical scavenging activity of the leaves of Tabernaemontana divaricata Linn. Petroleum ether, ethanol and aqueous extracts of T. divaricata were prepared with successive extraction in a soxhlet apparatus. Each extract was selected to study the free radical scavenging activity by superoxide scavenging assay method. It was found that the aqueous extract contained carbohydrates, glycosides, amino acids, flavonoids, tannins, alkaloids, and steroids, and the ethanolic extract contained glycosides, amino acids, flavonoids, tannins, alkaloids and steroids. The ethanolic extract of T. divaricata showed 58.7 +/- 0.62% inhibition in the superoxide scavenging model. The aqueous extract also showed almost similar activity (54.9 +/- 0.53% compared to the ethanolic extract), while petroleum ether extract showed poor inhibition of superoxide scavenging activity. All extracts showed the dose- and time-dependent inhibition of the superoxide scavenging activity. PMID:20140809

  10. DPPH free radical scavenger components from the fruits of Alpinia rafflesiana Wall. ex. Bak. (Zingiberaceae).

    PubMed

    Mohamad, Habsah; Abas, Faridah; Permana, Dharma; Lajis, Nordin H; Ali, Abdul Manaf; Sukari, Mohd Aspollah; Hin, Taufiq Y Y; Kikuzaki, Hiroe; Nakatani, Nobuji

    2004-01-01

    The methanol extract of the dried ripe fruits of Alpinia rafflesiana was investigated for its DPPH free radical scavenger constituents. 2',3',4',6'-Tetrahydroxychalcone (7), which has never been isolated from natural sources was found to be most active as a DPPH free radical scavenger with the IC50 value of 55 microM. Other known compounds isolated from this species include 5,6-dehydrokawain (1), flavokawin B (2). 1,7-diphenyl-5-hydroxy-6-hepten-3-one (3), (-)-pinocembrin (4), cardamonin (5) and (-)-pinostrobin (6). The DPPH free radical scavenger compounds were detected using TLC autographic analysis. The percentage inhibition of DPPH free radical scavenging activity was measured on isolates (5-7) using colorimetric analysis. PMID:15666539

  11. Radical scavenging potentials of single and combinatorial herbal formulations in vitro

    PubMed Central

    Ojiako, Okey A.; Chikezie, Paul C.; Ogbuji, Agomuo C.

    2015-01-01

    Reactive oxygen and nitrogen species (RONS) are involved in deleterious/beneficial biological processes. The present study sought to investigate the capacity of single and combinatorial herbal formulations of Acanthus montanus, Emilia coccinea, Hibiscus rosasinensis, and Asystasia gangetica to act as superoxide radicals (SOR), hydrogen peroxide (HP), nitric oxide radical (NOR), hydroxyl radical (HR), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical antagonists using in vitro models. The herbal extracts were single herbal formulations (SHfs), double herbal formulations (DHfs), triple herbal formulations (THfs), and a quadruple herbal formulation (QHf). The phytochemical composition and radical scavenging capacity index (SCI) of the herbal formulations were measured using standard methods. The flavonoids were the most abundant phytochemicals present in the herbal extracts. The SCI50 defined the concentration (μg/mL) of herbal formulation required to scavenge 50% of the investigated radicals. The SHfs, DHfs, THfs, and QHf SCI50 against the radicals followed the order HR > SOR > DPPH radical > HP > NOR. Although the various herbal formulations exhibited ambivalent antioxidant activities in terms of their radical scavenging capabilities, a broad survey of the results of the present study showed that combinatorial herbal formulations (DHfs, THfs, and QHf) appeared to exhibit lower radical scavenging capacities than those of the SHfs in vitro. PMID:27114938

  12. Radical scavenging potentials of single and combinatorial herbal formulations in vitro.

    PubMed

    Ojiako, Okey A; Chikezie, Paul C; Ogbuji, Agomuo C

    2016-04-01

    Reactive oxygen and nitrogen species (RONS) are involved in deleterious/beneficial biological processes. The present study sought to investigate the capacity of single and combinatorial herbal formulations of Acanthus montanus, Emilia coccinea, Hibiscus rosasinensis, and Asystasia gangetica to act as superoxide radicals (SOR), hydrogen peroxide (HP), nitric oxide radical (NOR), hydroxyl radical (HR), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical antagonists using in vitro models. The herbal extracts were single herbal formulations (SHfs), double herbal formulations (DHfs), triple herbal formulations (THfs), and a quadruple herbal formulation (QHf). The phytochemical composition and radical scavenging capacity index (SCI) of the herbal formulations were measured using standard methods. The flavonoids were the most abundant phytochemicals present in the herbal extracts. The SCI50 defined the concentration (μg/mL) of herbal formulation required to scavenge 50% of the investigated radicals. The SHfs, DHfs, THfs, and QHf SCI50 against the radicals followed the order HR > SOR > DPPH radical > HP > NOR. Although the various herbal formulations exhibited ambivalent antioxidant activities in terms of their radical scavenging capabilities, a broad survey of the results of the present study showed that combinatorial herbal formulations (DHfs, THfs, and QHf) appeared to exhibit lower radical scavenging capacities than those of the SHfs in vitro. PMID:27114938

  13. Evaluation of Antioxidant and Free Radical Scavenging Capacities of Polyphenolics from Pods of Caesalpinia pulcherrima

    PubMed Central

    Hsu, Feng-Lin; Huang, Wei-Jan; Wu, Tzu-Hua; Lee, Mei-Hsien; Chen, Lih-Chi; Lu, Hsiao-Jen; Hou, Wen-Chi; Lin, Mei-Hsiang

    2012-01-01

    Thirteen polyphenolics were isolated from fresh pods of Caesalpinia pulcherrima using various methods of column chromatography. The structures of these polyphenolics were elucidated as gallic acid (1), methyl gallate (2), 6-O-galloyl-d-glucoside (3), methyl 6-O-galloyl-β-d-glucoside (4), methyl 3,6-di-O-galloyl-α-d-glucopyranoside (5), gentisic acid 5-O-α-d-(6′-O-galloyl)glucopyranoside (6), guaiacylglycerol 4-O-β-d-(6′-O-galloyl)glucopyranoside (7), 3-methoxy-4-hydroxyphenol 1-O-β-d-(6′-O-galloyl) glucopyranoside (8), (+)-gallocatechin (9), (+)-catechin (10), (+)-gallocatechin 3-O-gallate (11), myricetin 3-rhamnoside (12), and ampelopsin (13). All isolated compounds were tested for their antioxidant activities in the 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and peroxynitrite radicals scavenging assays. Among those compounds, 11, 12, and 2 exhibited the best DPPH-, hydroxyl-, and peroxynitrite radical-scavenging activities, respectively. Compound 7 is a new compound, and possesses better scavenging activities towards DPPH but has equivalent hydroxyl radical scavenging activity when compared to BHT. The paper is the first report on free radical scavenging properties of components of the fresh pods of Caesalpinia pulcherrima. The results obtained from the current study indicate that the free radical scavenging property of fresh pods of Caesalpinia pulcherrima may be one of the mechanisms by which this herbal medicine is effective in several free radical mediated diseases. PMID:22754350

  14. Degradation of TAIC by water falling film dielectric barrier discharge--influence of radical scavengers.

    PubMed

    Rong, Shaopeng; Sun, Yabing

    2015-04-28

    This work describes the application of plasma generated by water falling film dielectric barrier discharge for the degradation of triallyl isocyanurate (TAIC). The results indicated that TAIC solution of 1000mg/L was effectively removed within 60min treatment at 120W output power. Six intermediates were identified and a possible evolution of the TAIC degradation process was continuously proposed basing on the results of mass spectrum analysis. The effects of metal ions and radical scavengers were investigated. Results showed that whatever hydrogen radical scavengers (carbon tetrachloride, perfluorooctane) or hydroxyl radical scavengers (iso-propyl alcohol, tert-butyl alcohol) all could further enhance the degradation processes, and both kings of radical scavengers could promote the generation of H2O2. In the present study, we employed a novel method by introducing the mixed additives of Fe(2+) and radical scavengers into the plasma. It was found that the reaction rate constant and energy efficiency were improved by 309.2% and 387.8%, respectively. Among the mixed additives, Fe(2+) could promote the decomposition and increase the oxidizing power of H2O2, which is generated from the plasma discharge and greatly enhanced by the radical scavengers. PMID:25668300

  15. Antioxidant and free-radical-scavenging effects of fruits of Dregea volubilis

    PubMed Central

    Biswas, Moulisha; Haldar, Pallab Kanti; Ghosh, Ashoke Kumar

    2010-01-01

    This study evaluated the in vitro antioxidant potential of petroleum ether (60–80°C), chloroform, and methanol extract of the fruits of Dregea volubilis Benth (Asclepiadaceae). The different antioxidant assays, including total antioxidant activity, reducing power, free radical, super oxide anion radical, nitric oxide scavenging, lipid peroxidation, and total phenolic content were studied. The extracts exhibited potent total antioxidant activity that increased with increasing amount of extract concentration, which was compared with standard drug vitamin C at different concentrations as extracts. The different concentrations of all the extracts and vitamin C showed inhibition on lipid peroxidation. In addition, all the extracts had effective reducing power, free radical scavenging, super oxide anion scavenging, nitric oxide scavenging, lipid peroxidation, and total phenolic content depending on concentration. These various antioxidant activities were compared with standard antioxidant such as vitamin C at different concentration as different extracts. PMID:22096333

  16. Development of nitroxide radicals-containing polymer for scavenging reactive oxygen species from cigarette smoke

    NASA Astrophysics Data System (ADS)

    Yoshitomi, Toru; Kuramochi, Kazuhiro; Binh Vong, Long; Nagasaki, Yukio

    2014-06-01

    We developed a nitroxide radicals-containing polymer (NRP), which is composed of poly(4-methylstyrene) possessing nitroxide radicals as a side chain via amine linkage, to scavenge reactive oxygen species (ROS) from cigarette smoke. In this study, the NRP was coated onto cigarette filters and its ROS-scavenging activity from streaming cigarette smoke was evaluated. The intensity of electron spin resonance signals of the NRP in the filter decreased after exposure to cigarette smoke, indicating consumption of nitroxide radicals. To evaluate the ROS-scavenging activity of the NRP-coated filter, the amount of peroxy radicals in an extract of cigarette smoke was measured using UV-visible spectrophotometry and 1,1-diphenyl-2-picrylhydrazyl (DPPH). The absorbance of DPPH at 517 nm decreased with exposure to cigarette smoke. When NRP-coated filters were used, the decrease in the absorbance of DPPH was prevented. In contrast, both poly[4-(cyclohexylamino)methylstyrene]- and poly(acrylic acid)-coated filters, which have no nitroxide radical, did not show any effect, indicating that the nitroxide radicals in the NRP scavenge the ROS in cigarette smoke. As a result, the extract of cigarette smoke passed through the NRP-coated filter has a lower cellular toxicity than smoke passed through poly[4-(cyclohexylamino)methylstyrene]- and poly(acrylic acid)-coated filters. Accordingly, NRP is a promising material for ROS scavenging from cigarette smoke.

  17. Influence of Total Anthocyanins from Bitter Melon (Momordica charantia Linn.) as Antidiabetic and Radical Scavenging Agents

    PubMed Central

    Güdr, Aytaç

    2016-01-01

    The majority of the antioxidant and antidiabetic activities of fruits are anthocyanins; a group of polyphenolics that are responsible for the color of many fruits, vegetables and flowers. The harvesting time, storage conditions, maturity, extraction steps etc. are very important for the biological activities based on the alteration of chemical composition. The free radical scavenging and antidiabetic activities of total anthocyanins from bitter melon (Momordica charantia Linn) fruit (TAMC) were evaluated by considering four harvesting times. The free radical scavenging activities of the TAMC samples were assessed using DPPH•, DMPD•+ and ABTS•+ assays against BHA, rutin and trolox standards. September as a harvesting period (TAMC-S) had effective DPPH• (SC50 2.55 ± 0.08 μg/mL), DMPD•+ (SC50 2.68 ± 0.09 μg/mL) and ABTS•+ (SC50 8.19 ± 0.09 μg/mL) scavenging activities compared with other samples and standards. In addition, August (TAMC-A) as a harvesting period showed very influential inhibitory activity against α-amylase (IC50 56.86 ± 1.12 μg/mL) and moderate inhibitory activity against α-glucosidase (IC50 88.19 ± 0.74 μg/mL). In comparison, pharmaceutical active ingredients such as acarbose exhibited anti-amylase and anti-glucosidase activities with IC50 values of 93.07 ± 1.49 μg/mL and 77.25 ± 1.20 μg/mL respectively. These results suggest that the correct selection of harvest period can significantly increase anthocyanin quantity because of the pharmaceutic properties of TAMC. Consequently, TAMC may be interesting for incorporation in pharmaceutical preparations for human health, since it can suppress hyperglycaemia that can be also used as food additives due to its antiradical activity. PMID:27610171

  18. Influence of Total Anthocyanins from Bitter Melon (Momordica charantia Linn.) as Antidiabetic and Radical Scavenging Agents.

    PubMed

    Güdr, Aytaç

    2016-01-01

    The majority of the antioxidant and antidiabetic activities of fruits are anthocyanins; a group of polyphenolics that are responsible for the color of many fruits, vegetables and flowers. The harvesting time, storage conditions, maturity, extraction steps etc. are very important for the biological activities based on the alteration of chemical composition. The free radical scavenging and antidiabetic activities of total anthocyanins from bitter melon (Momordica charantia Linn) fruit (TAMC) were evaluated by considering four harvesting times. The free radical scavenging activities of the TAMC samples were assessed using DPPH(•), DMPD(•+) and ABTS(•+) assays against BHA, rutin and trolox standards. September as a harvesting period (TAMC-S) had effective DPPH(•) (SC50 2.55 ± 0.08 μg/mL), DMPD(•+) (SC50 2.68 ± 0.09 μg/mL) and ABTS(•+) (SC50 8.19 ± 0.09 μg/mL) scavenging activities compared with other samples and standards. In addition, August (TAMC-A) as a harvesting period showed very influential inhibitory activity against α-amylase (IC50 56.86 ± 1.12 μg/mL) and moderate inhibitory activity against α-glucosidase (IC50 88.19 ± 0.74 μg/mL). In comparison, pharmaceutical active ingredients such as acarbose exhibited anti-amylase and anti-glucosidase activities with IC50 values of 93.07 ± 1.49 μg/mL and 77.25 ± 1.20 μg/mL respectively. These results suggest that the correct selection of harvest period can significantly increase anthocyanin quantity because of the pharmaceutic properties of TAMC. Consequently, TAMC may be interesting for incorporation in pharmaceutical preparations for human health, since it can suppress hyperglycaemia that can be also used as food additives due to its antiradical activity. PMID:27610171

  19. Free radical scavenging activity of Cleome gynandra L. leaves on adjuvant induced arthritis in rats.

    PubMed

    Narendhirakannan, R T; Subramanian, S; Kandaswamy, M

    2005-08-01

    The generation of free radicals has been implicated in the causation of several diseases of known and unknown etiologies such as, rheumatoid arthritis, diabetes, cancer, etc., and compounds that can scavenge free radicals have great potential in ameliorating these disease processes. The present study was aimed to investigate the possible anti-oxidant potential of Cleome gynandra leaf extract at a dose of 150 mg/kg body weight for 30 days on adjuvant induced arthritis in experimental rats. Oral administration of C. gynandra leaf extract significantly increased the levels of lipid peroxides and activities of catalase, glutathione peroxidase and decreased the levels of reduced glutathione and superoxide dismutase activity in arthritis induced rats. The free radical scavenging activity of the plant was further evidenced by histological observations made on the limb tissue. The presence of biologically active ingredients and vital trace elements in the leaves readily account for free radical scavenging property of C. gynandra. PMID:16132687

  20. Capsaicin, a tasty free radical scavenger: mechanism of action and kinetics.

    PubMed

    Galano, Annia; Martínez, Ana

    2012-01-26

    The free radical scavenging activity of capsaicin (CAP), which is the pungent component of hot chili peppers, has been studied in aqueous and lipid solutions, using the density functional theory. Different mechanisms of reaction have been considered: single electron transfer (SET), hydrogen transfer (HT), and radical adduct formation (RAF). Rate constants and branching ratios of the different channels of reaction are provided, as well as an interpretation of the UV-vis spectra. CAP is predicted to react faster in aqueous solution than in nonpolar media with oxygenated free radicals, and it was found to be a more efficient scavenger than melatonin and caffeine. It was also found that while SET does not contribute to the overall reactivity of CAP toward (•)OOH, (•)OOCH(3), and (•)OCH(3) radicals, it might be important for the reactions with more electrophilic radicals such as (•)OH, (•)OCCl(3), and (•)OOCCl(3). The main process, responsible for the peroxyl scavenging activity of CAP, was found to be the HT from the OH phenolic group. For the reaction with (•)OCH(3), on the other hand, the HT from allylic sites are predicted to be the main channels of reaction. In this particular case a wider product distribution is predicted. This supports the role of the reacting free radical on the preponderant mechanism of action of free radical scavengers. PMID:22188587

  1. [In vitro anti-inflammatory and free radical scavenging activities of flavans from Ilex centrochinensis].

    PubMed

    Li, Lu-jun; Yu, Li-juan; Li, Yan-ci; Liu, Meng-yuan; Wu, Zheng-zhi

    2015-04-01

    This study was carried out to evaluate the anti-inflammatory and free radical scavenging activities of flavans from flex centrochinensis S. Y. Hu in vitro and their structure-activity relationship. LPS-stimulated RAW 264.7 macrophage was used as inflammatory model. MTT assay for cell availability, Griess reaction for nitric oxide (NO) production, the content of TNF-alpha, IL-1beta, IL-6 and PGE, were detected with ELISA kits; DPPH, superoxide anion and hydroxyl free radicals scavenging activities were also investigated. According to the result, all flavans tested exhibited anti-inflammatory effect in different levels. Among them, compounds 1, 3, 4 and 6 showed potent anti-inflammatory effect through the inhibition of NO, TNF-alpha, IL-lp and IL-6, of which 1 was the most effective inhibitor, however, 2 and 5 were relatively weak or inactive. The order of free radical scavenging activities was similar to that of anti-inflammatory activities. Therefore, these results suggest that 3, 4 and 6, especially of 1, were,in part responsible for the anti-inflammatory and free radical scavenging activity of Ilex centrochinensis. Hydroxyl group at 4'-position of B-ring plays an important role in the anti-inflammatory and free radical scavenging capacities. PMID:26281592

  2. Methylglyoxal as a scavenger for superoxide anion-radical.

    PubMed

    Shumaev, K B; Lankin, V Z; Konovalova, G G; Grechnikova, M A; Tikhaze, A K

    2016-07-01

    Methylglyoxal at a concentration of 5 mM caused a significant inhibition of superoxide anion radical (O2 (·-)) comparable to the effect of Tirone. In the process of O2 (·-) generation in the system of egg phosphatidylcholine liposome peroxidation induced by the azo-initiator AIBN, a marked inhibition of chemiluminescence in the presence of 100 mM methylglyoxal was found. At the same time, methylglyoxal did not inhibit free radical peroxidation of low-density lipoprotein particles, which indicates the absence of interaction with methylglyoxal alkoxyl and peroxyl polyenoic lipid radicals. These findings deepen information about the role of methylglyoxal in the regulation of free radical processes. PMID:27599518

  3. Exploration of the kinetic and thermochemical abilities for the free radical scavenging of two quercetin conformers

    NASA Astrophysics Data System (ADS)

    Mendoza-Wilson, Ana María; Sotelo-Mundo, Rogerio R.; Balandrán-Quintana, René R.; Glossman-Mitnik, Daniel; Sántiz-gómez, Marco a.; García-orozco, karina D.

    2010-09-01

    Quercetin has a great antioxidant potential due to its large capacity for free radical scavenging. Although it has been found that conformational changes have a profound effect on its chemical properties, there are few studies where conformation is associated with the antioxidant activity. The aim of this investigation was to explore the kinetic and the thermochemical abilities of two quercetin conformers for the free radical scavenging. Quercetin unhydrate (QUH) and quercetin dihydrate (QDH) conformers were studied employing 2,2-diphenyl-1-picrylhydrazyl (DPPH rad ) as in vitro radical model, and catechol and 4-hexyl-resorcinol as reference systems, for identifying the oxidation products. QDH showed to be most effective under conditions of free radical excess, while QUH was most effective when the flavonoid far exceeds the concentration of free radical. It was found, by means of experimental and computational methods, that 4'-OH, 3-OH and 3'-OH are the main reactive sites of both conformers.

  4. Free Radical Scavenging and Analgesic Activities of Cucumis sativus L. Fruit Extract

    PubMed Central

    Kumar, D; Kumar, S; Singh, J; Narender; Rashmi; Vashistha, BD; Singh, N

    2010-01-01

    The aqueous fruit extract of Cucumis sativus L. was screened for free radical scavenging and analgesic activities. The extract was subjected to in vitro antioxidant studies at 250 and 500 μg/ml and analgesic study at the doses 250 and 500 mg/kg, respectively. The free radical scavenging was compared with ascorbic acid, BHA (Butylated hydroxyl anisole), whereas, the analgesic effect was compared with Diclofenac sodium (50 mg/kg). The C. sativus fruit extract showed maximum antioxidant and analgesic effect at 500 μg/ml and 500 mg/kg, respectively. The presence of flavonoids and tannins in the extract as evidenced by preliminary phytochemical screening suggests that these compounds might be responsible for free radical scavenging and analgesic effects. PMID:21264095

  5. Screening of Malian medicinal plants for antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities.

    PubMed

    Diallo, D; Marston, A; Terreaux, C; Touré, Y; Paulsen, B S; Hostettmann, K

    2001-08-01

    A total of 78 different extracts from 20 medicinal plants belonging to 14 plant families from Mali were tested for their antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities. Dichloromethane, methanol, water and ethanol extracts were used. TLC autobiography for antifungal activity was run with Cladosporium cucumerinum and Candida albicans. Extracts were also tested on the larvae of the mosquitoes Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus. Molluscicidal activities were established with the snails Biomphalaria glabrata, Biomphalaria pfeifferi and Bulinus truncatus. beta-Carotene and DPPH solutions sprayed on TLC plates were used for antioxidant and radical scavenging assays. Of the extracts investigated, 20% were antioxidant and radical scavengers, 19% fungicidal, 30% were larvicidal and 11% were molluscicidal. Three of the plant extracts, from Cussonia barteri (Araliaceae), Glinus oppositifolius (Aïzoaceae) and Lannea velutina (Anacardiaceae) gave positive responses in all four tests. PMID:11507731

  6. Aging of whiskey increases 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity.

    PubMed

    Aoshima, Hitoshi; Tsunoue, Hideaki; Koda, Hirofumi; Kiso, Yoshinobu

    2004-08-11

    1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of Japanese whiskey after various aging periods in oak barrels was measured to evaluate the antioxidative effects of whiskey. The activity of the whiskey increased with the aging period with high correlation. The activity of various types of whiskey was measured and shown to be correlated to the potentiation of the GABAA receptor response measured in a previous paper. However, the fragrant compounds in the whiskey which potentiated the GABAA receptor response had low DPPH radical scavenging activity, while phenol derivatives had high radical scavenging activity. The whiskey was extracted by pentane. The aqueous part showed the scavenging activity, whereas the pentane part did not. Thus, both the DPPH radical scavenging activity and the potentiation of the GABAA receptor response increased during whiskey aging in oak barrels, but were due to different components. The whiskey protected the H2O2-induced death of E. coli more than ethanol at the same concentration as that of the whiskey. The changes that occurred in the whiskey during aging may be the reason aged whiskies are so highly valued. PMID:15291502

  7. Effects of Functional Groups and Sugar Composition of Quercetin Derivatives on Their Radical Scavenging Properties.

    PubMed

    Kato, Komei; Ninomiya, Masayuki; Tanaka, Kaori; Koketsu, Mamoru

    2016-07-22

    Quercetin derivatives are widespread in the plant kingdom and exhibit various biological actions. The aim of this study was to investigate the structure-activity relationships of quercetin derivatives, with a focus on the influence of functional groups and sugar composition on their antioxidant capacity. A series of quercetin derivatives were therefore prepared and assessed for their DPPH radical scavenging properties. Isoquercetin O-gallates were more potent radical scavengers than quercetin. The systematic analysis highlights the importance of the distribution of hydroxy substituents in isoquercetin O-gallates to their potency. PMID:27314621

  8. Structure and radical scavenging activity relationships of pyrolytic lignins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This work deals with antioxidant properties of pyrolytic lignins against two free radicals, the 1,1-diphenyl-2-picrylhydrazyl and the 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid). Pyrolytic lignins produced by the thermal pyrolysis of the Etek lignin were extracted from the liquid pyrolysi...

  9. Electron Paramagnetic Resonance Study of the Free Radical Scavenging Capacity of Curcumin and Its Demethoxy and Hydrogenated Derivatives.

    PubMed

    Morales, Noppawan Phumala; Sirijaroonwong, Srisuporn; Yamanont, Paveena; Phisalaphong, Chada

    2015-01-01

    The quantitative free radical scavenging capacity of curcumin and its demethoxy derivatives (demethoxycurcumin (Dmc) and bisdemethoxycurcumin (Bdmc)) and hydrogenated derivatives (tetrahydrocurcumin (THC), hexahydrocurcumin (HHC) and octahydrocurcumin (OHC)) towards 1,1-diphenyl-2-picryl hydrazyl (DPPH), nitric oxide radical (NO), hydroxyl radical (HO(·)) and superoxide anion radical (O2(·)) were investigated by electron paramagnetic resonance (EPR) spectroscopy. One mole of the hydrogenated derivatives scavenged about 4 mol of the DPPH radical, while curcumin and Dmc scavenged about 3 mol of the DPPH radical. Curcumin and THC showed moderate scavenging activity towards NO, yielding 200 mmol of NO scavenged per 1 mol of the scavenger. In contrast, curcumin and its derivatives showed very low scavenging activity towards HO(·) and O2(·), yielding approximately only 3-12 mmol scavenged per 1 mol of the tested compounds. Our results suggest that curcumin and its derivatives principally act as chain breaking antioxidants rather than as direct free radical scavengers. Furthermore, we showed that the ortho-methoxyphenolic group and the heptadione linkage of these molecules greatly contributed to their DPPH and NO scavenging activity. PMID:26424013

  10. Inhibitory effect of free radical scavenger, MCI-186, in the increase of hydroxyl radical induced by iminodipropionitrile in rats.

    PubMed

    Nomoto, Nobuatsu

    2004-04-15

    Beta,beta'-Iminodipropionitrile (IDPN) is known to produce permanent motor behavioral abnormalities in rats. This behavior syndrome is also termed as "ECC Syndrome", the animal model for Gilles de la Tourette syndrome in humans. Some reports showed that these behavioral abnormalities are caused by monoamine changes. However, there was little research on the relation between IDPN-induced behavioral abnormalities and free radical. 3-Methyl-1-phenyl-2-pyrazolin-5-one (MCI-186), a newly synthesized free radical scavenger, exerts beneficial free radical scavenging and antioxidant characteristics. We investigated that MCI-186 inhibited the process of hydroxyl radical formation induced by IDPN administration in the rat brain. In the group of IDPN administration, hydroxyl radical levels exhibited predominant increase in most parts of the rat brain. In the group of IDPN and MCI-186 administration, hydroxyl radical levels marked significant decrease compared with those in the group of IDPN administration. Therefore, MCI-186 inhibited production of hydroxyl radical and might prove to be effective against ECC syndrome induced by IDPN. PMID:15050436

  11. Radiation inactivation analysis of enzymes. Effect of free radical scavengers on apparent target sizes

    SciTech Connect

    Eichler, D.C.; Solomonson, L.P.; Barber, M.J.; McCreery, M.J.; Ness, G.C.

    1987-07-15

    In most cases the apparent target size obtained by radiation inactivation analysis corresponds to the subunit size or to the size of a multimeric complex. In this report, we examined whether the larger than expected target sizes of some enzymes could be due to secondary effects of free radicals. To test this proposal we carried out radiation inactivation analysis on Escherichia coli DNA polymerase I, Torula yeast glucose-6-phosphate dehydrogenase, Chlorella vulgaris nitrate reductase, and chicken liver sulfite oxidase in the presence and absence of free radical scavengers (benzoic acid and mannitol). In the presence of free radical scavengers, inactivation curves are shifted toward higher radiation doses. Plots of scavenger concentration versus enzyme activity showed that the protective effect of benzoic acid reached a maximum at 25 mM then declined. Mannitol alone had little effect, but appeared to broaden the maximum protective range of benzoic acid relative to concentration. The apparent target size of the polymerase activity of DNA polymerase I in the presence of free radical scavengers was about 40% of that observed in the absence of these agents. This is considerably less than the minimum polypeptide size and may reflect the actual size of the polymerase functional domain. Similar effects, but of lesser magnitude, were observed for glucose-6-phosphate dehydrogenase, nitrate reductase, and sulfite oxidase. These results suggest that secondary damage due to free radicals generated in the local environment as a result of ionizing radiation can influence the apparent target size obtained by this method.

  12. Radical Scavenging Activity of the Essential Oil of Silver Fir (Abies alba)

    PubMed Central

    Yang, Seun-Ah; Jeon, Sang-Kyung; Lee, Eun-Jung; Im, Nam-Kyung; Jhee, Kwang-Hwan; Lee, Sam-Pin; Lee, In-Seon

    2009-01-01

    The essential oil of silver fir (Abies alba) is known to help respiratory system and have easing and soothing effect for muscle. In the present study, we investigated the chemical composition, cytotoxicity and its biological activities of silver fir (Abies alba) essential oil. The composition of the oil was analyzed by GC-MS and bornyl acetate (30.31%), camphene (19.81%), 3-carene (13.85%), tricyclene (12.90%), dl-limonene (7.50%), α-pinene (2.87%), caryophyllene (2.18%), β-phellandrene (2.13%), borneol (1.74%), bicyclo[2.2.1]hept-2-ene,2,3-dimethyl (1.64%) and α-terpinene (1.24%) were the major components in the oil. The results tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay indicated that the oil showed no cytotoxic effect, at concentrations of 1 and 5%, for as long as 24 and 3 h, respectively. The antiradical capacity was evaluated by measuring the scavenging activity of the essential oil on the 2,20-diphenylpicrylhydrazyl (DPPH) and 2,2'-azino-bis 3-ethyl benzothiazoline-6-sulfonic acid (ABTS) radicals. The oil was able to reduce the both radicals dose-dependently, and the concentration required for 50% reduction (RC50) against DPPH radicals (2.7 ± 0.63%) was lower than ABTS radicals (8.5 ± 0.27%). The antibacterial activity of the oil was also evaluated using disc diffusion method against Staphylococcus aureus, Streptococcus mutans, Listeria monocytogenes, Acinetobacter baumannii, Escherichia coli, and Vibrio parahaemolyticcus. The oil exhibited no antibacterial activity against all the bacterial strains tested except S. aureus of mild activity. PMID:19430614

  13. Radical Scavenging Activity of the Essential Oil of Silver Fir (Abies alba).

    PubMed

    Yang, Seun-Ah; Jeon, Sang-Kyung; Lee, Eun-Jung; Im, Nam-Kyung; Jhee, Kwang-Hwan; Lee, Sam-Pin; Lee, In-Seon

    2009-05-01

    The essential oil of silver fir (Abies alba) is known to help respiratory system and have easing and soothing effect for muscle. In the present study, we investigated the chemical composition, cytotoxicity and its biological activities of silver fir (Abies alba) essential oil. The composition of the oil was analyzed by GC-MS and bornyl acetate (30.31%), camphene (19.81%), 3-carene (13.85%), tricyclene (12.90%), dl-limonene (7.50%), alpha-pinene (2.87%), caryophyllene (2.18%), beta-phellandrene (2.13%), borneol (1.74%), bicyclo[2.2.1]hept-2-ene,2,3-dimethyl (1.64%) and alpha-terpinene (1.24%) were the major components in the oil. The results tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay indicated that the oil showed no cytotoxic effect, at concentrations of 1 and 5%, for as long as 24 and 3 h, respectively. The antiradical capacity was evaluated by measuring the scavenging activity of the essential oil on the 2,20-diphenylpicrylhydrazyl (DPPH) and 2,2'-azino-bis 3-ethyl benzothiazoline-6-sulfonic acid (ABTS) radicals. The oil was able to reduce the both radicals dose-dependently, and the concentration required for 50% reduction (RC(50)) against DPPH radicals (2.7 +/- 0.63%) was lower than ABTS radicals (8.5 +/- 0.27%). The antibacterial activity of the oil was also evaluated using disc diffusion method against Staphylococcus aureus, Streptococcus mutans, Listeria monocytogenes, Acinetobacter baumannii, Escherichia coli, and Vibrio parahaemolyticcus. The oil exhibited no antibacterial activity against all the bacterial strains tested except S. aureus of mild activity. PMID:19430614

  14. Hydroxyl radical scavenging-based method for evaluation of TiO₂ photocatalytic activity.

    PubMed

    Mencigar, Danijela Pucko; Strlič, Matija; Štangar, Urška Lavrenčič; Korošec, Romana Cerc

    2013-01-01

    A novel hydroxyl radical scavenging method was developed to establish the photocatalytic activity of TiO₂ thin films. Transparent TiO₂ thin films were prepared on soda-lime glass substrates using the sol-gel method and characterized using X-ray diffraction. During photoirradiation in aqueous buffered solutions, activity of the films was followed using the substituted nitrobenzene N,N'-(5-nitro-1,3-phenylene)bisglutaramide as a hydroxyl radical scavenger and its hydroxylated products were quantified using HPLC. The yield of hydroxyl radicals was evaluated at various pH of the reaction media, and reflected the dependence of the rate of the hydroxylation reaction on the experimental conditions and on the different qualities of the TiO₂ thin films. The proposed method allows for direct assessment of hydroxyl radical production, it is straightforward and is proposed for routine use. PMID:24362997

  15. Free radical scavenging activity and lipoxygenase inhibition of Mahonia aquifolium extract and isoquinoline alkaloids

    PubMed Central

    Rackova, Lucia; Oblozinsky, Marek; Kostalova, Daniela; Kettmann, Viktor; Bezakova, Lydia

    2007-01-01

    Roots and stem-bark of Mahonia aquifolium (Oregon grape) (Berberidaceae) are effectively used in the treatment of skin inflammatory conditions. In the present study, the effect of Mahonia aquifolium crude extract and its two representative alkaloid fractions containing protoberberine and bisbenzylisoquinoline (BBIQ) alkaloids on activity of 12-lipoxygenase (12-LOX), was studied. The reactivity with 1,1-diphenyl-2-picryl-hydrazyl (DPPH), a free stable radical, was evaluated to elucidate the rate of possible lipid-derived radical scavenging in the mechanism of the enzyme inhibition. The results indicate that although the direct radical scavenging mechanism cannot be ruled out in the lipoxygenase inhibition by Mahonia aquifolium and its constituents, other mechanisms based on specific interaction between enzyme and alkaloids could play the critical role in the lipoxygenase inhibition rather than non-specific reactivity with free radicals. PMID:17634120

  16. Relationship between structure, properties, and the radical scavenging activity of morin

    NASA Astrophysics Data System (ADS)

    Mendoza-Wilson, Ana María; Santacruz-Ortega, Hisila; Balandrán-Quintana, René R.

    2011-05-01

    The relationship between structure, kinetic, thermochemical and electronic properties of the morin flavonoid was researched in order to establish the molecular characteristics related to its maximum radical scavenging activity. The reaction of morin with the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH rad ) was carried out in ethanol, through the hydrogen-atom transfer (HAT) mechanism. Morin showed the highest radical scavenging activity under conditions of excess of free radical. It was found, by means of experimental and computational methods, that 3-OH, 2'-OH and 4'-OH are the main reactive sites, as well as that the 3-O-2'-O quinone is the first product of the reaction, tending to prevail in the enol form through a tautomerism effect, whose observed structural arrangement corresponds to the 3-O semiquinone.

  17. Synthesis and radical scavenger properties of novel spirochromenes derived from steroid sapogenins.

    PubMed

    Ramos-Enríquez, Manuel A; Medina-Campos, Omar N; Pedraza-Chaverri, José; Iglesias-Arteaga, Martín A

    2015-06-01

    Tandem aldol condensation between steroid sapogenins and hydroxylated benzaldehydes afforded steroidal spirochromenes. Compounds that bear a phenolic hydroxyl group at position C-6', obtained by a reaction with 2,5-dihydroxybenzaldehyde, showed approximately 80% of maximal radical scavenging activity in the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) assay at 288 nM. In contrast, the starting steroid sapogenins and the spirochromenes without a phenolic group in the side chain proved to be inactive. PMID:25824324

  18. The Butanol Fraction of Bitter Melon (Momordica charantia) Scavenges Free Radicals and Attenuates Oxidative Stress

    PubMed Central

    Kim, Hyun Young; Sin, Seung Mi; Lee, Sanghyun; Cho, Kye Man; Cho, Eun Ju

    2013-01-01

    To investigate radical scavenging effects and protective activities of bitter melon (Momordica charantia) against oxidative stress, in vitro and a cellular system using LLC-PK1 renal epithelial cells were used in this study. The butanol (BuOH) fraction of bitter melon scavenged 63.4% and 87.1% of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals at concentrations of 250 and 500 μg/mL, respectively. In addition, the BuOH fraction of bitter melon effectively scavenged hydroxyl radicals (·OH). At all concentrations tested, the scavenging activity of the BuOH fraction was more potent than that of the positive control, ascorbic acid. Furthermore, under the LLC-PK1 cellular model, the cells showed a decline in viability and an increase in lipid peroxidation through oxidative stress induced by pyrogallol, a generator of superoxide anion (O2−). However, the BuOH fraction of bitter melon significantly and dose-dependently inhibited cytotoxicity. In addition, 3-morpholinosydnonimine (SIN-1), a generator of peroxynitrite (ONOO−) formed by simultaneous releases of nitric oxide and O2−, caused cytotoxicity in the LLC-PK1 cells while the BuOH fraction of bitter melon ameliorated oxidative damage induced by ONOO−. These results indicate that BuOH fraction of bitter melon has protective activities against oxidative damage induced by free radicals. PMID:24471105

  19. In vitro radical scavenging and cytotoxic activities of novel hybrid selenocarbamates.

    PubMed

    Romano, Beatriz; Plano, Daniel; Encío, Ignacio; Palop, Juan Antonio; Sanmartín, Carmen

    2015-04-15

    Novel selenocyanate and diselenide derivatives containing a carbamate moiety were synthesised and evaluated in vitro to determine their cytotoxic and radical scavenging properties. Cytotoxic activity was tested against a panel of human cell lines including CCRF-CEM (lymphoblastic leukaemia), HT-29 (colon carcinoma), HTB-54 (lung carcinoma), PC-3 (prostate carcinoma), MCF-7 (breast adenocarcinoma), 184B5 (non-malignant, mammary gland derived) and BEAS-2B (non-malignant, derived from bronchial epithelium). Most of the compounds displayed high antiproliferative activity with GI50 values below 10μM in MCF-7, CCRF-CEM and PC-3 cells. Radical scavenging properties of the new selenocompounds were confirmed testing their ability to scavenge DPPH and ABTS radicals. Based on the activity of selenium-based glutathione peroxidases (GPxs), compounds 1a, 2e and 2h were further screened for their capacity to reduce hydrogen peroxide under thiol presence. Results suggest that compound 1a mimics GPxs activity. Cytotoxic parameters, radical scavenging activity and ADME profile point to 1a as promising drug candidate. PMID:25792142

  20. Effect of lu-duo-wei on scavenging superoxide and hydroxyl radicals in vitro.

    PubMed

    Fang, Y Z; Sun, C P; Tian, X H; Cong, J H

    1998-01-01

    Irradiation of a riboflavin-containing system by ultraviolet light was used to produce superoxide radical (.O2-). Hydroxyl radical (.OH) was generated by the system of Fe(II)-H2O2. Using electron spin resonance and spin trapping techniques, the effect of Lu-Duo-Wei, a capsule consisting extracts of green tea, Fructus Lycii and Semen Ziziphi Spinosae, on scavenging .O2- and .OH was observed. The results showed that the efficiency of scavenging .O2- and .OH by Lu-Duo-Wei was much higher than that by tea polyphenol alone. It is suggested that the synergistic action of tea polyphenol and other components are responsible for the scavenging effect of Lu-Duo-Wei on .O2- and .OH. PMID:9799967

  1. 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.

    PubMed

    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. PMID:26616951

  2. Free radical scavenging and radioprotective effects of carnosine and anserine

    NASA Astrophysics Data System (ADS)

    Fu, Haiying; Katsumura, Yosuke; Lin, Mingzhang; Muroya, Yusa; Hata, Kuniki; Fujii, Kentaro; Yokoya, Akinari; Hatano, Yoshihiko

    2009-12-01

    Two histidine-containing natural dipeptides, carnosine and anserine (β-alanyl-1-methyl- L-histidine), have been examined for their antioxidant and radioprotective abilities. Pulse radiolysis studies indicated the antioxidative properties of carnosine and anserine aqueous solutions at different pH. The rate constants for the reaction OH radical with carnosine at neutral pH were determined to be 5.3×10 9 M -1 s -1 at 300 nm, and 4.1×10 9 M -1 s -1 at 400 nm, respectively. Carnosine and anserine also protected plasmid pUC18 DNA from X-ray radiation-induced strand breaks as evidenced from the studies by agarose gel electrophoresis. Carnosine showed higher protective efficiency under the experimental conditions. Our data demonstrated that carnosine and anserine may play an important role in the maintenance of the antioxidant system.

  3. The Efficacy of Edaravone (Radicut), a Free Radical Scavenger, for Cardiovascular Disease

    PubMed Central

    Kikuchi, Kiyoshi; Tancharoen, Salunya; Takeshige, Nobuyuki; Yoshitomi, Munetake; Morioka, Motohiro; Murai, Yoshinaka; Tanaka, Eiichiro

    2013-01-01

    Edaravone was originally developed as a potent free radical scavenger, and has been widely used to treat acute ischemic stroke in Japan since 2001. Free radicals play an important role in the pathogenesis of a variety of diseases, such as cardiovascular diseases and stroke. Therefore, free radicals may be targets for therapeutic intervention in these diseases. Edaravone shows protective effects on ischemic insults and inflammation in the heart, vessel, and brain in experimental studies. As well as scavenging free radicals, edaravone has anti-apoptotic, anti-necrotic, and anti-cytokine effects in cardiovascular diseases and stroke. Edaravone has preventive effects on myocardial injury following ischemia and reperfusion in patients with acute myocardial infarction. Edaravone may represent a new therapeutic intervention for endothelial dysfunction in the setting of atherosclerosis, heart failure, diabetes, or hypertension, because these diseases result from oxidative stress and/or cytokine-induced apoptosis. This review evaluates the potential of edaravone for treatment of cardiovascular disease, and covers clinical and experimental studies conducted between 1984 and 2013. We propose that edaravone, which scavenges free radicals, may offer a novel option for treatment of cardiovascular diseases. However, additional clinical studies are necessary to verify the efficacy of edaravone. PMID:23880849

  4. Computational Studies of Free Radical-Scavenging Properties of Phenolic Compounds

    PubMed Central

    Alov, Petko; Tsakovska, Ivanka; Pajeva, Ilza

    2015-01-01

    For more than half a century free radical-induced alterations at cellular and organ levels have been investigated as a probable underlying mechanism of a number of adverse health conditions. Consequently, significant research efforts have been spent for discovering more effective and potent antioxidants / free radical scavengers for treatment of these adverse conditions. Being by far the most used antioxidants among natural and synthetic compounds, mono- and polyphenols have been the focus of both experimental and computational research on mechanisms of free radical scavenging. Quantum chemical studies have provided a significant amount of data on mechanisms of reactions between phenolic compounds and free radicals outlining a number of properties with a key role for the radical scavenging activity and capacity of phenolics. The obtained quantum chemical parameters together with other molecular descriptors have been used in quantitative structure-activity relationship (QSAR) analyses for the design of new more effective phenolic antioxidants and for identification of the most useful natural antioxidant phenolics. This review aims at presenting the state of the art in quantum chemical and QSAR studies of phenolic antioxidants and at analysing the trends observed in the field in the last decade. PMID:25547098

  5. Polyphenolics profile, antioxidant and radical scavenging activity of leaves and stem of Raphanus sativus L.

    PubMed

    Beevi, Syed Sultan; Narasu, Mangamoori Lakshmi; Gowda, Bandi Boje

    2010-03-01

    Aerial parts (leaves and stem) of Raphanus sativus, which are usually discarded were found to possess potent antioxidant and radical scavenging activity, as measured by standard antioxidant assays. Methanolic and acetone extracts of R. sativus leaves had total polyphenolic content of 86.16 and 78.77 mg/g dry extract, which were comparable to the traditional rich sources such as green tea and black tea. HPLC identification of polyphenolics indicated the presence of catechin, protocatechuic acid, syringic acid, vanillic acid, ferulic acid, sinapic acid, o-coumaric acid, myricetin, and quercetin in leaves and stem. Among the different extraction solvents, methanolic extract of leaves and stem showed potent reductive capacity, significantly inhibited linoleic acid peroxidation and displayed metal chelating activity. Further, they scavenged free radicals effectively with IC50 (half maximal inhibitory concentration) of 31 and 42 microg/ml for DPPH radical, 23 and 52 microg/ml for superoxide radical, 67 and 197 microg/ml for hydrogen peroxide,and 56 and 62 microg/ml for nitric oxide, respectively. Leaves showed most potent antioxidant and radical scavenging activity as compared to stem, which may be accounted for the high polyphenolic content. Leaves and stem of R. sativus,often under-utilized part of this vegetable, thus possessed considerable amount of polyphenolics. Hence, it should be egarded as a potential source of natural antioxidants and could be effectively employed as an ingredient in health or in functional food. PMID:20072818

  6. Preliminary studies on the activities of spin traps as scavengers of free radicals

    SciTech Connect

    Ogunbiyi, P.O.; Washington, I. )

    1991-03-15

    The spin trapping agents, N-t-Butyl-a-phenyl-nitrone (PBN) and 5,5-Dimethyl-1-pyroline-N-oxide (DMPO) have been used to investigate the primary free radicals involved in various tissue injuries. Also, PBN and DMPO can provide some protection against free radical-induced lung injuries. However, their therapeutic potentials as free radical scavengers remained unexamined. In this study, the effects of PBN and DMPO on guinea pig lung microsomal lipid peroxidation were investigated using thiobarbituric acid-reactive substance assay. Superoxide anions (O{sup 2}{minus}) were generated in an enzymatic and a non-enzymatic system. PBN and DMPO each, significantly inhibited NADPH-stimulated lipid peroxidation irrespective of the presence of Fe{sup 3+}. Cytochrome c reduction by the enzymatic and nitro blue tetrazolium reduction by the non-enzymatic O{sup 2}{minus} generating systems were both inhibited by PBN and DMPO as well as superoxide dismutase and dimethyl sulfoxide when compared with the controls. The spin traps exhibited lower potencies in these systems than the reference compounds, SOD and DMSO, which are well established as O{sup 2}{minus} and hydroxyl radical scavengers respectively. Results demonstrate the free radical scavenging properties of PBN and DMPO. This is an indication of their possible usefulness as antioxidants.

  7. Computational studies of free radical-scavenging properties of phenolic compounds.

    PubMed

    Alov, Petko; Tsakovska, Ivanka; Pajeva, Ilza

    2015-01-01

    For more than half a century free radical-induced alterations at cellular and organ levels have been investigated as a probable underlying mechanism of a number of adverse health conditions. Consequently, significant research efforts have been spent for discovering more effective and potent antioxidants / free radical scavengers for treatment of these adverse conditions. Being by far the most used antioxidants among natural and synthetic compounds, mono- and polyphenols have been the focus of both experimental and computational research on mechanisms of free radical scavenging. Quantum chemical studies have provided a significant amount of data on mechanisms of reactions between phenolic compounds and free radicals outlining a number of properties with a key role for the radical scavenging activity and capacity of phenolics. The obtained quantum chemical parameters together with other molecular descriptors have been used in quantitative structure-activity relationship (QSAR) analyses for the design of new more effective phenolic antioxidants and for identification of the most useful natural antioxidant phenolics. This review aims at presenting the state of the art in quantum chemical and QSAR studies of phenolic antioxidants and at analysing the trends observed in the field in the last decade. PMID:25547098

  8. Radical scavenging and antioxidant activities of essential oil components--an experimental and computational investigation.

    PubMed

    Sharopov, Farukh S; Wink, Michael; Setzer, William N

    2015-01-01

    The antioxidant activities of eighteen different essential oil components have been determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay, the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical cation assay, and the ferric reducing antioxidant power (FRAP) assay. The phenolic compounds, carvacrol, thymol, and eugenol, showed the best antioxidant activities, while camphor, menthol, and menthone were the least active. The structural and electronic properties of the essential oil components were assessed using density functional theory (DFT) at the B3LYP/6-311++G** level. Correlations between calculated electronic properties and antioxidant activities were generally poor, but bond-dissociation energies (BDEs) seem to correlate with DPPH radical-scavenging activities, and the ferric reducing antioxidant power (FRAP) assay correlated with vertical ionization potentials calculated at the Hartree-Fock/6-311++G** level. PMID:25920239

  9. Electronic structure of some thymol derivatives correlated with the radical scavenging activity: theoretical study.

    PubMed

    Javan, Ashkan Jebelli; Javan, Marjan Jebeli

    2014-12-15

    Molecules acting as antioxidants capable of scavenging reactive oxygen species (ROS) are of upmost importance in the living cell. Thymol derivatives exhibit various antioxidant activities and potential health benefits. Exploration of structure-radical scavenging activity (SAR) was approached with a wide range of thymol derivatives. To accomplish this task, the DPPH experimental assay along with quantum-chemical calculations were also employed for these compounds. By comparing the structural properties of the derivatives of interest, their antioxidant activity was explained by the formation of an intramolecular hydrogen bond and the presence of unsaturated double bond (-CHCH substituent) in their radical spices. Moreover, the delocalization of odd electrons in these radicals has been investigated by natural bond orbital analysis and interpretation of spin density maps. Reactivity order of the compound towards the ROS: HO, HOO, and O2(-) was found to be as HO>HOO > O2(-). PMID:25038698

  10. Antioxidant and free radical scavenging effects of the tannins of Terminalia catappa L.

    PubMed

    Lin, C C; Hsu, Y F; Lin, T C

    2001-01-01

    Reactive oxygen species (ROS) react with biological molecules and destroy the structure of cells and eventually cause free radical-induced disease such as inflammation and cancer. Previous studies showed that an aqueus extract of Terminalia catappa L. exhibited superoxide radical scavenger activity and modification of mitomycin C-induced clasto-genicity. In order to investigate the multiple antioxidant effect of the tannin components of T. catappa L., their ability to prevent lipid peroxidation, superoxide formation and their free radical scavenging activity were evaluated. The results indicated that all of these components showed potent antioxidant activity. Punicalagin and punicalin were the most abundant components and had the strongest anti-oxidative effects of this group of tannins. PMID:11299741

  11. Free radical scavenging activity of novel thiazolidine-2,4-dione derivatives.

    PubMed

    Berczyński, Paweł; Kruk, Irena; Piechowska, Teresa; Ceylan-Unlusoy, Meltem; Bozdağ-Dündar, Oya; Aboul-Enein, Hassan Y

    2013-01-01

    Free radical activity towards superoxide anion radical (O2•¯), hydroxyl radical (HO(•)) and 2,2-diphenyl-1-picrylhydrazyl (DPPH(•)) of a series of novel thiazolidine-2,4-dione derivatives (TSs) was examined using chemiluminescence, electron paramagnetic resonance (EPR) and EPR spin trapping techniques. 5,5-Dimethyl-1-pyrroline-N-oxide (DMPO) was applied as the spin trap. Superoxide radical was produced in the potassium superoxide/18-crown-6 ether dissolved in dimethyl sulfoxide. Hydroxyl radical was generated in the Fenton reaction (Fe(II) + H2O2. It was found that TSs showed a slight scavenging effect (15-38% reduction at 2.5 mmol/L concentration) of the DPPH radical and a high scavenging effect of O2•¯ (41-88%). The tested compounds showed inhibition of HO(•)-dependent DMPO-OH spin adduct formation (the amplitude of EPR signal decrease ranged from 20 to 76% at 2.5 mmol/L concentration. Our findings present new group compounds of relatively high reactivity towards free radicals. PMID:23225772

  12. Alkoxyl radical-scavenging activity of edaravone in patients with traumatic brain injury.

    PubMed

    Dohi, Kenji; Satoh, Kazue; Mihara, Yuko; Nakamura, Shunsuke; Miyake, Yasuhumi; Ohtaki, Hirokazu; Nakamachi, Tomoya; Yoshikawa, Toshikazu; Shioda, Seiji; Aruga, Tohru

    2006-11-01

    Lipid peroxidation is caused by reactive oxygen species (ROS) and is involved in traumatic brain injury (TBI). Consequently, a therapeutic strategy for TBI may be to control lipid peroxidation. The only drug approved to date for blocking lipid peroxidation is edaravone (MCI-186), a novel free-radical scavenger shown to exert neuroprotective effects in acute ischemic stroke. Although edaravone scavenges hydroxyl and nitric oxide radicals, its effect on alkoxyl radicals (OR-), which also contribute to lipid peroxidation, is unknown. To date, the study of free radicals in blood has been severely hampered by technical difficulties in their detection. We used an in vitro and ex vivo electron spin resonance (ESR) method employing 5,5-dimethyl-1-pyrroline-N-oxide as a spin trap to investigate whether edaravone can scavenge OR-. By mixing either methemoglobin or human blood with tert-butyl hydroperoxide, we found that this technique can detect OR- generated in vitro. We also found that generated OR- can be completely absorbed by administration of edaravone in vitro (400 microM). Analysis of jugular venous blood collected from 17 TBI patients immediately before and 20 minutes after the administration of edaravone (30 mg, i.v.) revealed higher OR- levels in the untreated patients blood than in normal control blood samples. However, treatment with edaravone suppressed these OR- levels by 24.6% (radical intensity = 71.1 +/- 5.2-53.6 +/- 5.2; p < 0.01). Thus, edaravone can scavenge OR- and significantly reduce levels of these radicals in TBI patients. The novel ex vivo ESR method described here provides a valuable clinical measure of oxidative stress. PMID:17115906

  13. Aluminium ion-promoted radical-scavenging reaction of methylated hydroquinone derivatives.

    PubMed

    Nakanishi, Ikuo; Ohkubo, Kei; Ogawa, Yukihiro; Matsumoto, Ken-Ichiro; Ozawa, Toshihiko; Fukuzumi, Shunichi

    2016-08-16

    The effect of the aluminium ion (Al(3+)) on the scavenging reaction of a 2,2-diphenyl-1-picrylhydrazyl radical (DPPH˙), as a reactivity model of reactive oxygen species, with hydroquinone (QH2) and its methylated derivatives (MenQH2, n = 1-4) was investigated using stopped-flow and electrochemical techniques in a hydroalcoholic medium. The second-order rate constants (k) for the DPPH˙-scavenging reaction of the hydroquinones increased with the increasing number of methyl substituents. Upon addition of Al(3+), the k values significantly increased depending on the concentration of Al(3+). Such an accelerating effect of Al(3+) on the DPPH˙-scavenging rates of the hydroquinones results from the remarkable positive shift of the one-electron reduction potential (Ered) of DPPH˙ in the presence of Al(3+). These results demonstrate that Al(3+), a strong Lewis acid, can act as a radical-scavenging promoter by stabilising the one-electron reduced species of the radical, although Al(3+) is reported not only to act as a pro-oxidant but also to strongly interact with biomolecules, showing toxicities. PMID:27492849

  14. In vitro activity of almond skin polyphenols for scavenging free radicals and inducing quinone reductase.

    PubMed

    Chen, C-Y Oliver; Blumberg, Jeffrey B

    2008-06-25

    Observational studies and clinical trials suggest nut intake, including almonds, is associated with an enhancement in antioxidant defense and a reduction in the risk of cancer and cardiovascular disease. Almond skins are rich in polyphenols (ASP) that may contribute to these putative benefits. To assess their potential mechanisms of action, we tested the in vitro effect of ASP extracted with methanol (M) or a gastrointestinal juice mimic (GI) alone or in combination with vitamins C (VC) or E (VE) (1-10 micromol/L) on scavenging free radicals and inducing quinone reductase (QR). Flavonoid profiles from ASP-M and -GI extracts were different from one another. ASP-GI was more potent in scavenging HOCl and ONOO (-) radicals than ASP-M. In contrast, ASP-M increased and ASP-GI decreased QR activity in Hepa1c1c7 cells. Adding VC or VE to ASP produced a combination- and dose-dependent action on radical scavenging and QR induction. In comparison to their independent actions, ASP-M plus VC were less potent in scavenging DPPH, HOCl, ONOO (-), and O 2 (-) (*). However, the interaction between ASP-GI plus VC promoted their radical scavenging activity. Combining ASP-M plus VC resulted in a synergistic interaction, inducing QR activity, but ASP-GI plus VC had an antagonistic effect. On the basis of their total phenolic content, the measures of total antioxidant activity of ASP-M and -GI were comparable. Thus, in vitro, ASP act as antioxidants and induce QR activity, but these actions are dependent upon their dose, method of extraction, and interaction with antioxidant vitamins. PMID:18512942

  15. Chemical composition and radical scavenging activity of essential oil and methanolic extract of Eremostachys azerbaijanica Rech.f. from Iran.

    PubMed

    Asnaashari, Solmaz; Afshar, Fariba Heshmati; Ebrahimi, Atefeh; Moghadam, Sedigheh Bamdad; Delazar, Abbas

    2016-01-01

    In the present study, the chemical composition of the essential oil and methanol (MeOH) extract of aerials of E. azerbaijanica were identified. Furthermore, the free radical scavenging properties of the volatile oil as well as the MeOH extract of the plant were assessed. The essential oil of the air-dried aerial parts was obtained by hydro-distillation using a Clevenger-type apparatus. The oil was then analyzed by gas chromatography-mass spectrometry and gas chromatography with flame ionization detector. Soxhlet extraction was performed on the aerial parts using n-hexane, dichloromethane and MeOH. The MeOH extract was then subjected to solid-phase extraction using a C18 Sep-Pak cartridge. Isolation and structural elucidation of the pure components was accomplished by high-performance liquid chromatography and spectroscopic methods (UV, (1)H-NMR). The free radical scavenging properties were determined by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. A total of 59 components representing 95.9% of the oil constituents were identified which were primarily characterized as terpenoids or aliphatic skeletons. The major components of the oil were hexahydrofarnesyl acetone (27.1%), 2-methyl-6-propyl-dodecane (16.4%) and tricosane (9.3%). One flavonoid (luteolin-7-O-rutinoside) and one phenylethanoid (verbascoside) were also isolated and identified from the MeOH extract. The results of DPPH assays showed that the essential oil of E. azerbaijanica possessed weak free radical scavenging activity whereas the MeOH extract and its pure constituents showed significant scavenging activities in comparison with positive controls. PMID:27168750

  16. Chemical composition and radical scavenging activity of essential oil and methanolic extract of Eremostachys azerbaijanica Rech.f. from Iran

    PubMed Central

    Asnaashari, Solmaz; Afshar, Fariba Heshmati; Ebrahimi, Atefeh; Moghadam, Sedigheh Bamdad; Delazar, Abbas

    2016-01-01

    In the present study, the chemical composition of the essential oil and methanol (MeOH) extract of aerials of E. azerbaijanica were identified. Furthermore, the free radical scavenging properties of the volatile oil as well as the MeOH extract of the plant were assessed. The essential oil of the air-dried aerial parts was obtained by hydro-distillation using a Clevenger-type apparatus. The oil was then analyzed by gas chromatography–mass spectrometry and gas chromatography with flame ionization detector. Soxhlet extraction was performed on the aerial parts using n-hexane, dichloromethane and MeOH. The MeOH extract was then subjected to solid-phase extraction using a C18 Sep-Pak cartridge. Isolation and structural elucidation of the pure components was accomplished by high-performance liquid chromatography and spectroscopic methods (UV, 1H-NMR). The free radical scavenging properties were determined by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. A total of 59 components representing 95.9% of the oil constituents were identified which were primarily characterized as terpenoids or aliphatic skeletons. The major components of the oil were hexahydrofarnesyl acetone (27.1%), 2-methyl-6-propyl-dodecane (16.4%) and tricosane (9.3%). One flavonoid (luteolin-7-O-rutinoside) and one phenylethanoid (verbascoside) were also isolated and identified from the MeOH extract. The results of DPPH assays showed that the essential oil of E. azerbaijanica possessed weak free radical scavenging activity whereas the MeOH extract and its pure constituents showed significant scavenging activities in comparison with positive controls. PMID:27168750

  17. Neuroprotective effects of the free radical scavenger Edaravone (MCI-186) in mice permanent focal brain ischemia.

    PubMed

    Shichinohe, Hideo; Kuroda, Satoshi; Yasuda, Hiroshi; Ishikawa, Tatsuya; Iwai, Masaru; Horiuchi, Masatsugu; Iwasaki, Yoshinobu

    2004-12-17

    The present study was aimed to evaluate the effect of the free radical scavenger Edaravone on infarct volume due to permanent MCA occlusion in mice and, if so, to elucidate the mechanism of its neuroprotective effects. Male Balb/c mice were subjected to permanent middle cerebral artery occlusion and were treated with 3.0 mg/kg of Edaravone or vehicle 30 min before ischemia. Infarct volume was assessed by 2,3,5-triphenyltetrazolium chloride (TTC) method after 24 h. Furthermore, in situ detection of superoxide in the ipsilateral neocortex was carried out using the superoxide-sensitive dye dihydroethidium (DHE) staining technique. Pretreatment with 3.0 mg/kg of Edaravone ameliorated the tissue damage in the infarct rim and significantly reduced infarct volume to about 77% of the control (p<0.05). Semi-quantitative measurement of red fluorescence emitted from DHE revealed that the superoxide increased in the ischemic core at 1 h after the onset of ischemia and extended towards the infarct rim at 3 and 6 h, and that pretreatment with 3.0 mg/kg of Edaravone significantly inhibited the increase of superoxide in the infarct rim at 3 and 6 h (p<0.01). Double staining with DHE and monoclonal antibody against NeuN showed that the majority of the nuclei positive for DHE were also positive for NeuN. These findings suggest that Edaravone salvages the boundary zone of infarct by scavenging reactive oxygen species especially in the neurons during permanent focal cerebral ischemia. PMID:15542075

  18. Cranberry flavonoids prevent toxic rat liver mitochondrial damage in vivo and scavenge free radicals in vitro.

    PubMed

    Lapshina, Elena A; Zamaraeva, Maria; Cheshchevik, Vitali T; Olchowik-Grabarek, Ewa; Sekowski, Szymon; Zukowska, Izabela; Golovach, Nina G; Burd, Vasili N; Zavodnik, Ilya B

    2015-06-01

    The present study was undertaken for further elucidation of the mechanisms of flavonoid biological activity, focusing on the antioxidative and protective effects of cranberry flavonoids in free radical-generating systems and those on mitochondrial ultrastructure during carbon tetrachloride-induced rat intoxication. Treatment of rats with cranberry flavonoids (7 mg/kg) during chronic carbon tetrachloride-induced intoxication led to prevention of mitochondrial damage, including fragmentation, rupture and local loss of the outer mitochondrial membrane. In radical-generating systems, cranberry flavonoids effectively scavenged nitric oxide (IC50  = 4.4 ± 0.4 µg/ml), superoxide anion radicals (IC50  = 2.8 ± 0.3 µg/ml) and hydroxyl radicals (IC50  = 53 ± 4 µg/ml). The IC50 for reduction of 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH) was 2.2 ± 0.3 µg/ml. Flavonoids prevented to some extent lipid peroxidation in liposomal membranes and glutathione oxidation in erythrocytes treated with UV irradiation or organic hydroperoxides as well as decreased the rigidity of the outer leaflet of the liposomal membranes. The hepatoprotective potential of cranberry flavonoids could be due to specific prevention of rat liver mitochondrial damage. The mitochondria-addressed effects of flavonoids might be related both to radical-scavenging properties and modulation of various mitochondrial events. PMID:25962994

  19. Comparative study of copper(II)-curcumin complexes as superoxide dismutase mimics and free radical scavengers.

    PubMed

    Barik, Atanu; Mishra, Beena; Kunwar, Amit; Kadam, Ramakant M; Shen, Liang; Dutta, Sabari; Padhye, Subhash; Satpati, Ashis K; Zhang, Hong-Yu; Indira Priyadarsini, K

    2007-04-01

    Two stoichiometrically different copper(II) complexes of curcumin (stoichiometry, 1:1 and 1:2 for copper:curcumin), were examined for their superoxide dismutase (SOD) activity, free radical-scavenging ability and antioxidant potential. Both the complexes are soluble in lipids and DMSO. The formation constants of the complexes were determined by voltammetry. EPR spectra of the complexes in DMSO at 77K showed that the 1:2 Cu(II)-curcumin complex is square planar and the 1:1 Cu(II)-curcumin complex is distorted orthorhombic. Cu(II)-curcumin complex (1:1) with larger distortion from square planar structure shows higher SOD activity. These complexes inhibit gamma-radiation induced lipid peroxidation in liposomes and react with DPPH acting as free radical scavengers. One-electron oxidation of the two complexes by radiolytically generated azide radicals in Tx-100 micellar solutions produced phenoxyl radicals, indicating that the phenolic moiety of curcumin in the complexes participates in free radical reactions. Depending on the structure, these two complexes possess different SOD activities, free radical neutralizing abilities and antioxidant potentials. In addition, quantum chemical calculations with density functional theory have been performed to support the experimental observations. PMID:17240482

  20. Decomposition and mineralization of cefaclor by ionizing radiation: kinetics and effects of the radical scavengers.

    PubMed

    Yu, Seungho; Lee, Byungjin; Lee, Myunjoo; Cho, Il-Hyoung; Chang, Soon-Woong

    2008-05-01

    There has been recent growing interest in the presence of antibiotics in different environmental sectors. One considerable concern is the potential development of antibiotic-resistant bacteria in the environment, even at low concentrations. Cefaclor, one of the beta-lactam antibiotics, is widely used as an antibiotic. Kinetic studies were conducted to evaluate the decomposition and mineralization of cefaclor using gamma radiation. Cefaclor, 30 mg/l, was completely degraded with 1,000 Gy of gamma radiation. At a concentration of 30 mg/l, the removal efficiency, represented by the G-value, decreased with increasing accumulated radiation dose. Batch kinetic experiments with initial aqueous concentrations of 8.9, 13.3, 20.0 and 30.0mg/l showed the decomposition of cefaclor using gamma radiation followed a pseudo first-order reaction, and the dose constant increased with lower initial concentrations. At a given radiation dose, the G-values increased with higher initial cefaclor concentrations. The experimental results using methanol and thiourea as radical scavengers indicated that ()OH radicals were more closely associated with the radiolytic decomposition of cefaclor than other radicals, such as e(aq)(-) or ()H. The radical scavenger effects were tested under O(2) and N(2)O saturations for the enhancement of the TOC percentage removal efficiencies in the radiolytic decomposition of cefaclor. Under O(2) saturation, 90% TOC removal was observed with 100,000 Gy. Oxygen is well known to play a considerable role in the degradation of organic substances with effective chain reaction pathways. According to the effective radical reactions, the enhanced TOC percentage removal efficiencies might be based on the fast conversion reactions of e(aq)(-) and ()H with O(2) into oxidizing radicals, such as O(2)(-) and HO(2)(), respectively. 100% TOC removal was obtained with N(2)O gas at 20,000 Gy, as reducing radicals, such as e(aq)(-) and ()H, are scavenged by N(2)O and converted

  1. Nitrate-induced photolysis in natural waters: Controls on concentrations of hydroxyl radical photo-intermediates by natural scavenging agents

    SciTech Connect

    Brezonik, P.L.; Fulkerson-Brekken, J.

    1998-10-01

    The importance of the principal natural scavenging agents for hydroxyl radicals ({sup {sm_bullet}}OH) was evaluated, and a general framework was developed to predict the significance of nitrate-induced, {sup {sm_bullet}}OH-mediated degradation of aquatic contaminants. Rate constants for *OH scavenging by dissolved organic matter (DOM) from five surface water sources were in a narrow range which is similar to previously reported values and suggests that the importance of DOM as a {sup {sm_bullet}}OH sink can be estimated simply from the dissolved organic carbon (DOC) concentration of a water. Scavenging of {sup {sm_bullet}}*OH by carbonate and bicarbonate is generally less important, but these ions can be the major cause of *OH scavenging in low DOC, high alkalinity waters. Use of the framework is illustrated by predicting levels of {sup {sm_bullet}}OH and half-lives of the corn herbicide acetochlor in waters ranging from pristine to highly influenced by agricultural activities.

  2. A study on scavenging effects of Chinese medicine on superoxide anion radicals by pulse radiolysis

    NASA Astrophysics Data System (ADS)

    Fengmei, Li; Andong, Liu; Hongchun, Gu; Shaojie, Di

    1993-10-01

    A study on scavenging and dismutation effects on superoxide anion radical (·O -2) by using two Chinese antiaging medicine-Salvia Miltiorrhiza injection (S.M.) and Sulekang capsule (S.C.) were performed by pulse radiolysis. The absorption spectra of ·O -2 have been redetermined in radiolysis of aqueous solution of sodium format. The absorption maximum is at about 250nm. The results suggested that S.M. and S.C. can dismutate and scavenge ·O -2. The experimental scavenging rate of S.M. (150μg/ml) and S.C. (250μg/ml) were 89.6% and 69.5% respectively.

  3. Coumarin-Chalcone Hybrids as Peroxyl Radical Scavengers: Kinetics and Mechanisms.

    PubMed

    Mazzone, Gloria; Galano, Annia; Alvarez-Idaboy, Juan R; Russo, Nino

    2016-04-25

    The primary antioxidant activity of coumarin-chalcone hybrids has been investigated using the density functional and the conventional transition state theories. Their peroxyl radical scavenging ability was studied in solvents of different polarity and taking into account different reaction mechanisms. It was found that the activity of the hybrids increases with the polarity of the environment and the number of phenolic sites. In addition, their peroxyl radical scavenging activity is larger than those of the corresponding nonhybrid coumarin and chalcone molecules. This finding is in line with previous experimental evidence. All the investigated molecules were found to react faster than Trolox with (•)OOH, regardless of the polarity of the environment. The role of deprotonation on the overall activity of the studied compounds was assessed. The rate constants and branching ratios for the reactions of all the studied compounds with (•)OOH are reported for the first time. PMID:26998844

  4. Efficient scavenging of β-carotene radical cations by antiinflammatory salicylates.

    PubMed

    Cheng, Hong; Liang, Ran; Han, Rui-Min; Zhang, Jian-Ping; Skibsted, Leif H

    2014-02-01

    The radical cation generated during photobleaching of β-carotene is scavenged efficiently by the anion of methyl salicylate from wintergreen oil in a second-order reaction approaching the diffusion limit with k2 = 3.2 × 10(9) L mol(-1) s(-1) in 9 : 1 v/v chloroform-methanol at 23 °C, less efficiently by the anion of salicylic acid with 2.2 × 10(8) L mol(-1) s(-1), but still of possible importance for light-exposed tissue. Surprisingly, acetylsalicylate, the aspirin anion, reacts with an intermediate rate in a reaction assigned to the anion of the mixed acetic-salicylic acid anhydride formed through base induced rearrangements. The relative scavenging rate of the β-carotene radical cation by the three salicylates is supported by DFT-calculations. PMID:24336797

  5. DPPH radical-scavenging effect of several phenylpropanoid compounds and their glycoside derivatives.

    PubMed

    Tominaga, Hitoshi; Kobayashi, Yuka; Goto, Takashi; Kasemura, Kazuo; Nomura, Masato

    2005-04-01

    Eugenol, isoeugenol, caffeic acid, ferulic acid, isoferulic acid, estragole, trans-anethole, and paeonol are components of a Chinese herbal medicine used as a painkiller and stomachic. We investigated the potential role of these compounds as antioxidants. We studied the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging effect of these molecules, together with some glycoside derivatives, to ascertain their potential in reducing the levels of activated oxygen species in vivo. The DPPH radical-scavenging effects of eugenol, isoeugenol, and the glycoside derivatives of caffeic acid, ferulic acid, and isoferulic acid (SC(50)=8-28 microM) were similar to those of alpha-tocopherol, which was used as a positive control. PMID:15802883

  6. Evaluation of willow herb's (Epilobium angustofolium L.) antioxidant and radical scavenging capacities.

    PubMed

    Stajner, D; Popović, B M; Boza, P

    2007-12-01

    The present study investigated the antioxidative properties of root, leaf and stalk of Epilobium angustofolium L. The activities of antioxidant enzymes (superoxide dismutase, catalase, peroxidase), quantities of malonyldialdehyde, superoxide and hydroxyl radicals and reduced glutathione and also the content of total flavonoids, chlorophylls a and b, carotenoids, vitamin C and soluble proteins were determined. The results indicate that extracts from all plant organs exhibited antioxidant activity. The highest antioxidant activity was observed in the leaves. Radical scavenging capacity (RSC), determined by DPPH assay, was highest in the leaves as well as total reducing power determined by FRAP assay. Lipofuscin 'plant age pigments' were also determined. PMID:17661326

  7. Antioxidant and radical-scavenging activities of Slovak honeys - An electron paramagnetic resonance study.

    PubMed

    Zalibera, Michal; Staško, Andrej; Šlebodová, Anna; Jančovičová, Viera; Čermáková, Tatiana; Brezová, Vlasta

    2008-09-15

    The antioxidant properties of 15 honey samples from different floral sources and various Slovak regions were investigated by means of electron paramagnetic resonance spectroscopy. Cation radical of ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) diammonium salt), DPPH (1,1-diphenyl-2-picrylhydrazyl) and hydroxyl radicals generated by the photochemical decomposition of hydrogen peroxide were used as oxidants. The antioxidant activities found with ABTS(+), expressed as trolox equivalent antioxidant capacity (TEAC), ranged from 0.15 to 1.14mmolkg(-1), and those determined with DPPH, from 0.04 to 0.32mmolkg(-1). TEAC values correlated well with results found by elimination of DPPH, and both values revealed a linear relationship with the concentration of phenolics obtained with the Folin-Ciocalteu phenol test (expressed as gallic acid equivalents, GAE). The colour coordinates (CIE L(∗)a(∗)b(∗)), as well as reflectance spectra determined for original honeys using a white background, demonstrated that the colour difference (ΔE(∗)) and coordinate b(∗) interrelate with TEAC values. The radical-scavenging capacities (RSC) of the honey samples determined in the experiments with photochemically decomposed hydrogen peroxide, generating reactive OH radicals in the presence of spin trapping agent, differ from those found with ABTS(+) and DPPH. Here, probably, the reactive OH radicals, having higher redox potential, are scavenged by a variety of compounds not effective with ABTS(+) and DPPH (e.g., saccharides, proteins). PMID:26049247

  8. Evaluation of Antioxidant, Free Radical Scavenging, and Antimicrobial Activity of Quercus incana Roxb.

    PubMed Central

    Sarwar, Rizwana; Farooq, Umar; Khan, Ajmal; Naz, Sadia; Khan, Sara; Khan, Afsar; Rauf, Abdur; Bahadar, Haji; Uddin, Reaz

    2015-01-01

    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 Q. incana Roxb. In vitro antioxidant activity of the plant fractions were determined by 1,1-diphenyl-2-picrylhydrazyl and nitric oxide scavenging method. Total phenolic contents were determined by gallic acid equivalent and antimicrobial activities were determined by agar well diffusion method. It was observed that Q. 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 Q. incana Roxb. showed immense antifungal activity against Aspergillus niger (32 mm ± 0.55) and A. flavus (28 mm ± 0.45). Similarly n-butanol fraction showed relatively good antioxidant activity with IC50 value of 55.4 ± 0.21 μg/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 Q. 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. PMID:26635607

  9. Kinetic Reaction Mechanism of Sinapic Acid Scavenging NO2 and OH Radicals: A Theoretical Study.

    PubMed

    Lu, Yang; Wang, AiHua; Shi, Peng; Zhang, Hui; Li, ZeSheng

    2016-01-01

    The mechanism and kinetics underlying reactions between the naturally-occurring antioxidant sinapic acid (SA) and the very damaging ·NO2 and ·OH were investigated through the density functional theory (DFT). Two most possible reaction mechanisms were studied: hydrogen atom transfer (HAT) and radical adduct formation (RAF). Different reaction channels of neutral and anionic sinapic acid (SA-) scavenging radicals in both atmosphere and water medium were traced independently, and the thermodynamic and kinetic parameters were calculated. We find the most active site of SA/SA- scavenging ·NO2 and ·OH is the -OH group in benzene ring by HAT mechanism, while the RAF mechanism for SA/SA- scavenging ·NO2 seems thermodynamically unfavorable. In water phase, at 298 K, the total rate constants of SA eliminating ·NO2 and ·OH are 1.30×108 and 9.20×109 M-1 S-1 respectively, indicating that sinapic acid is an efficient scavenger for both ·NO2 and ·OH. PMID:27622460

  10. Antioxidant activity and free radical-scavenging capacity of Gynura divaricata leaf extracts at different temperatures

    PubMed Central

    Wan, Chunpeng; Yu, Yanying; Zhou, Shouran; Liu, Wei; Tian, Shuge; Cao, Shuwen

    2011-01-01

    Background: Extraction temperature influences the total phenolic content (TPC), total flavonoid content (TFC) of medicinal plant extracts to a great extend. TPC and TFC are the principle activity constituents present in the plant. The effects of extraction temperature on TPC, TFC and free radical-scavenging capacity of Gynura divaricata leaf extracts are worth to study. Materials and Methods: Folin–Ciocalteu and aluminum chloride colorimetric assay were used to determine the TPC and TFC of Gynura divaricata leaf extracts at different temperatures. The antioxidant and free radical-scavenging activity were measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and phosphomolybdenum methods. Results: TPC and TFC were significantly elevated with increasing extraction temperature (from 40°C to 100°C). However, TPC and TFC were not significantly different (P > 0.05) at the extraction temperatures 90°C and 100°C. Also, the extracts obtained at a higher temperature exhibited a significant free radical-scavenging activity compared with extraction at lower temperatures (P < 0.05). The TPCs (13.95-36.68 mg gallic acid equivalent/g dry material) were highly correlated with DPPH (R2 = 0.9229), ABTS (R2 = 0.9951) free radical-scavenging capacity, and total antioxidant activity (R2 = 0.9872) evaluated by phosphomolybdenum method. Conclusion: The TPC and TFC of G. divaricata leaf was significantly influenced by the extraction temperatures, which were the main antioxidant constituents present in the G. divaricata plant. PMID:21472078

  11. Radical scavenging and anti-lipoperoxidative activities of Smallanthus sonchifolius leaf extracts.

    PubMed

    Valentová, Katerina; Sersen, Frantisek; Ulrichová, Jitka

    2005-07-13

    Radical scavenging and anti-lipoperoxidative effects of two organic fractions and two aqueous extracts from the leaves of a neglected Andean crop-yacon (Smallanthus sonchifolius Poepp. & Endl., Asteraceae) were determined using various in vitro models. The extracts' total phenolic content was 10.7-24.6%. They exhibited DPPH (IC50 16.14-33.39 microg/mL) and HO* scavenging activities (4.49-6.51 mg/mL). The extracts did not scavenge phenylglyoxylic ketyl radicals, but they retarded their formation. In the xanthine/xanthine oxidase superoxide radical generating system, the extracts' activities were 26.10-37.67 superoxide dismutase equivalents/mg. As one of the extracts displayed xanthine oxidase inhibitory activity, the effect of the extracts on a nonenzymatically generated superoxide was determined (IC50 7.36-21.01 microg/mL). The extracts inhibited t-butyl hydroperoxide-induced lipoperoxidation of microsomal and mitochondrial membranes (IC50 22.15-465.3 microg/mL). These results make yacon leaves a good candidate for use as a food supplement in the prevention of chronic diseases involving oxidative stress. PMID:15998117

  12. Preparation of Egg White Liquid Hydrolysate (ELH) and Its Radical-Scavenging Activity.

    PubMed

    Noh, Dong Ouk; Suh, Hyung Joo

    2015-09-01

    In the present study, an optimum protease was selected to hydrolyze the egg white liquid protein for the antioxidant peptides. Alcalase treatment yielded the highest amount of α-amino groups (15.27 mg/mL), while the control (no enzymatic hydrolysis) showed the lowest amount of α-amino groups (1.53 mg/mL). Alcalase also gave the highest degree of hydrolysis (DH) value (43.2%) and was more efficient for egg white liquid hydrolysis than the other enzymes. The Alcalase hydrolysate had the highest radical-scavenging activity (82.5%) at a concentration of 5.0 mg/mL. The conditions for enzymatic hydrolysis of egg white liquid with Alcalase were selected as substrate : water ratio of 2:1. Five percent Alacalse treatment did not show significant (P>0.05) increases of DH and α-amino nitrogen content after 24 h-hydrolysis. Thirty two hour-hydrolysis with 5% Alcalase is sufficient to make antioxidative egg white liquid hydrolysate from egg white liquid. DPPH and ABTS radical-scavenging activities were significantly (P<0.05) higher after enzymatic digestion. These results suggest that active peptides released from egg-white protein are effective radical-scavengers. Thus, this approach may be useful for the preparation of potent antioxidant products. PMID:26451355

  13. Extracts, anthocyanins and procyanidins from Aronia melanocarpa as radical scavengers and enzyme inhibitors.

    PubMed

    Bräunlich, Marie; Slimestad, Rune; Wangensteen, Helle; Brede, Cato; Malterud, Karl E; Barsett, Hilde

    2013-03-01

    Extracts, subfractions, isolated anthocyanins and isolated procyanidins B2, B5 and C1 from the berries and bark of Aronia melanocarpa were investigated for their antioxidant and enzyme inhibitory activities. Four different bioassays were used, namely scavenging of the diphenylpicrylhydrazyl (DPPH) radical, inhibition of 15-lipoxygenase (15-LO), inhibition of xanthine oxidase (XO) and inhibition of α-glucosidase. Among the anthocyanins, cyanidin 3-arabinoside possessed the strongest and cyanidin 3-xyloside the weakest radical scavenging and enzyme inhibitory activity. These effects seem to be influenced by the sugar units linked to the anthocyanidin. Subfractions enriched in procyanidins were found to be potent α-glucosidase inhibitors; they possessed high radical scavenging properties, strong inhibitory activity towards 15-LO and moderate inhibitory activity towards XO. Trimeric procyanidin C1 showed higher activity in the biological assays compared to the dimeric procyanidins B2 and B5. This study suggests that different polyphenolic compounds of A. melanocarpa can have beneficial effects in reducing blood glucose levels due to inhibition of α-glucosidase and may have a potential to alleviate oxidative stress. PMID:23459328

  14. Preparation of Egg White Liquid Hydrolysate (ELH) and Its Radical-Scavenging Activity

    PubMed Central

    Noh, Dong Ouk; Suh, Hyung Joo

    2015-01-01

    In the present study, an optimum protease was selected to hydrolyze the egg white liquid protein for the antioxidant peptides. Alcalase treatment yielded the highest amount of α-amino groups (15.27 mg/mL), while the control (no enzymatic hydrolysis) showed the lowest amount of α-amino groups (1.53 mg/mL). Alcalase also gave the highest degree of hydrolysis (DH) value (43.2%) and was more efficient for egg white liquid hydrolysis than the other enzymes. The Alcalase hydrolysate had the highest radical-scavenging activity (82.5%) at a concentration of 5.0 mg/mL. The conditions for enzymatic hydrolysis of egg white liquid with Alcalase were selected as substrate : water ratio of 2:1. Five percent Alacalse treatment did not show significant (P>0.05) increases of DH and α-amino nitrogen content after 24 h-hydrolysis. Thirty two hour-hydrolysis with 5% Alcalase is sufficient to make antioxidative egg white liquid hydrolysate from egg white liquid. DPPH and ABTS radical-scavenging activities were significantly (P<0.05) higher after enzymatic digestion. These results suggest that active peptides released from egg-white protein are effective radical-scavengers. Thus, this approach may be useful for the preparation of potent antioxidant products. PMID:26451355

  15. Extracts, Anthocyanins and Procyanidins from Aronia melanocarpa as Radical Scavengers and Enzyme Inhibitors

    PubMed Central

    Bräunlich, Marie; Slimestad, Rune; Wangensteen, Helle; Brede, Cato; Malterud, Karl E.; Barsett, Hilde

    2013-01-01

    Extracts, subfractions, isolated anthocyanins and isolated procyanidins B2, B5 and C1 from the berries and bark of Aronia melanocarpa were investigated for their antioxidant and enzyme inhibitory activities. Four different bioassays were used, namely scavenging of the diphenylpicrylhydrazyl (DPPH) radical, inhibition of 15-lipoxygenase (15-LO), inhibition of xanthine oxidase (XO) and inhibition of α-glucosidase. Among the anthocyanins, cyanidin 3-arabinoside possessed the strongest and cyanidin 3-xyloside the weakest radical scavenging and enzyme inhibitory activity. These effects seem to be influenced by the sugar units linked to the anthocyanidin. Subfractions enriched in procyanidins were found to be potent α-glucosidase inhibitors; they possessed high radical scavenging properties, strong inhibitory activity towards 15-LO and moderate inhibitory activity towards XO. Trimeric procyanidin C1 showed higher activity in the biological assays compared to the dimeric procyanidins B2 and B5. This study suggests that different polyphenolic compounds of A. melanocarpa can have beneficial effects in reducing blood glucose levels due to inhibition of α-glucosidase and may have a potential to alleviate oxidative stress. PMID:23459328

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

    PubMed

    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. PMID:27396195

  17. Free-Radical-Scavenging, Antityrosinase, and Cellular Melanogenesis Inhibitory Activities of Synthetic Isoflavones.

    PubMed

    Lu, Tzy-Ming; Ko, Horng-Huey; Ng, Lean-Teik; Hsieh, Yen-Pin

    2015-06-01

    In this study, we examined the potential of synthetic isoflavones for application in cosmeceuticals. Twenty-five isoflavones were synthesized and their capacities of free-radical-scavenging and mushroom tyrosinase inhibition, as well as their impact on cell viability of B16F10 murine melanoma cells and HaCaT human keratinocytes were evaluated. Isoflavones that showed significant mushroom tyrosinase inhibitory activities were further studied on reduction of cellular melanin formation and antityrosinase activities in B16F10 melanocytes in vitro. Among the isoflavones tested, 6-hydroxydaidzein (2) was the strongest scavenger of both ABTS(.+) and DPPH(.) radicals with SC50 values of 11.3 ± 0.3 and 9.4 ± 0.1 μM, respectively. Texasin (20) exhibited the most potent inhibition of mushroom tyrosinase (IC50 14.9 ± 4.5 μM), whereas retusin (17) showed the most efficient inhibition both of cellular melanin formation and antityrosinase activity in B16F10 melanocytes, respectively. In summary, both retusin (17) and texasin (20) exhibited potent free-radical-scavenging capacities as well as efficient inhibition of cellular melanogenesis, suggesting that they are valuable hit compounds with potential for advanced cosmeceutical development. PMID:26080742

  18. Prevention of granulocyte-mediated oxidant lung injury in rats by a hydroxyl radical scavenger, dimethylthiourea.

    PubMed Central

    Fox, R B

    1984-01-01

    Toxic, partially reduced metabolites of oxygen (toxic oxygen radicals) are increasingly implicated in acute leukocyte-mediated tissue injury. To further probe the roles of oxygen radicals in acute lung edema, I studied the effects of a recently described and very potent oxygen radical scavenger, dimethylthiourea (DMTU) (Fox, R. B., R. N. Harada, R. M. Tate, and J. E. Repine, 1983, J. Appl. Physiol., 55:1456-1459) on polymorphonuclear leukocyte (PMN) oxidant function and on two types of lung injury mediated by oxygen radicals and PMN. DMTU (10 mM) blocked 79% of hydroxyl radical (OH) production by PMN in vitro without interfering with other PMN functions, such as O-2 production, myeloperoxidase activity, chemotaxis, degranulation, or aggregation. When isolated rat lung preparations were perfused with PMN activated to produce OH, lung weights were increased from 2.3 +/- 0.2 to 11.2 +/- 0.8 g. DMTU (10 mM) prevented 70% of these increases (lung weights, 5.0 +/- 1.1 g, P less than 0.005). Finally, when intact rats were exposed to 100% O2 for 66 h, lung weight:body weight ratios were increased from 5.78 +/- 0.33 to 8.87 +/- 0.16 g. DMTU (500 mg/kg) prevented 83% of this hyperoxia-induced lung edema in vivo (lung:body weight ratios, 6.05 +/- 0.21, P less than 0.001). Pharmacokinetic studies showed that DMTU diffused effectively into lung interstitial fluids and had a relatively long half-life (25-35 h) in the circulation. Because a variety of oxygen radicals, such as superoxide (O-2), hydrogen peroxide (H2O2), or OH are produced by PMN, there is usually some uncertainty about which one is responsible for injury. However, in these studies, DMTU did not scavenge O-2 and scavenged H2O2 only very slowly while scavenging OH very effectively. Therefore, DMTU may be useful in the investigation of the roles of oxygen radicals, especially OH, in acute granulocyte-mediated tissue injury. PMID:6090504

  19. MCI-186 (edaravone), a novel free radical scavenger, protects against acute autoimmune myocarditis in rats.

    PubMed

    Nimata, Masaomi; Okabe, Taka-aki; Hattori, Miki; Yuan, Zuyi; Shioji, Keisuke; Kishimoto, Chiharu

    2005-12-01

    In this study, we tested the hypothesis that MCI-186 (3-methyl-1-phenyl-2-pyrazolin-5-one; edaravone), a novel free radical scavenger, protects against acute experimental autoimmune myocarditis (EAM) in rats by the radical scavenging action associated with the suppression of cytotoxic myocardial injury. Recent evidence suggests that oxidative stress may play a role in myocarditis. We administered MCI-186 intraperitoneally at 1, 3, and 10 mg.kg(-1).day(-1) to rats with EAM for 3 wk. The results were compared with untreated rats with EAM. MCI-186 treatment did not affect hemodynamics. MCI-186 treatment (3 and 10 mg.kg(-1).day(-1)) reduced the severity of myocarditis as assessed by comparing the heart-to-body weight ratio and pathological scores. Myocardial interleukin-1beta (IL-1beta)-positive cells and myocardial oxidative stress overload with DNA damage in rats with EAM given MCI-186 treatment were significantly less compared with those of the untreated rats with EAM. In addition, MCI-186 treatment decreased not only the myocardial protein carbonyl contents but also the myocardial thiobarbituric acid reactive substance products in rats with EAM. The formation of hydroxyl radicals in MCI-186-treated heart homogenates was decreased compared with untreated heart homogenates. Furthermore, cytotoxic activities of lymphocytes of rats with EAM treated with MCI-186 were significantly lower compared with those of the untreated rats with EAM. Hydroxyl radicals may be involved in the development of myocarditis. MCI-186 protects against acute EAM in rats associated with scavenging hydroxyl free radicals, resulting in the suppression of autoimmune-mediated myocardial damage associated with reduced oxidative stress state. PMID:16100244

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

    PubMed Central

    Okoh, Sunday O.; Asekun, Olayinka T.; Familoni, Oluwole B.; Afolayan, Anthony J.

    2014-01-01

    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. PMID:26784871

  1. Development of a fluorescent probe for measurement of peroxyl radical scavenging activity in biological samples.

    PubMed

    Güçlü, Kubilay; Kıbrıslıoğlu, Gülşah; Özyürek, Mustafa; Apak, Reşat

    2014-02-26

    In antioxidant activity testing, it has been argued that assays capable of measuring the inhibitive action against the biologically relevant peroxyl radicals (ROO(•)) from a controllable source are preferable in terms of simulating physiological conditions because ROO(•) is the predominant free radical found in lipid oxidation in foods and biological systems. A new fluorescent probe, p-aminobenzoic acid (PABA), was developed for selective measurement of peroxyl radical scavenging (PRS) activity of biological samples, in view of the fact that the existing PRS assays are quite laborious and require the application of strictly optimized conditions. The earlier probe, β-phycoerythrin, of a similar PRS assay of wide use, oxygen radical absorbance capacity (ORAC), varies from lot to lot of production, undergoes photobleaching, and interacts with polyphenols via non-specific protein binding, while the current probe, fluorescein, undergoes undesired fluorescence (FL) quenching and side reactions. The developed technique is based on the fluorescence decrease of the PABA probe (within an optimal time of 30 min) because of its oxidation by ROO(•), generated from the thermal dissociation of 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH). In the absence of the scavenger, ROO(•) reacted with the probe, generating non-fluorescent products, and caused a decrease in PABA fluorescence, whereas the ROO(•) scavenger resulted in a fluorescence increase because of the inhibition of the probe oxidation by ROO(•). Thus, the fluorescence increment of intact PABA is proportional to the ROO(•) scavenging activity of samples. The linear range of relative fluorescence intensity versus the PABA concentration was in the interval of 0.5-5.0 μM. Assay precision and accuracy were assessed by analyzing two spiked homogenates of liver and kidney at clinically relevant concentrations with 97-105% recovery and 2.3% interday reproducibility. The proposed method was

  2. Determination of Radical Scavenging Activity and Total Phenols of Wine and Spices: A Randomized Study.

    PubMed

    Lugemwa, Fulgentius Nelson; Snyder, Amanda L; Shaikh, Koonj

    2013-01-01

    Thirty eight bottles of red wine (Carbanet Sauvignon) were randomly selected based on vintage, region, price, and age (number of months in a barrel). The total phenolic content of each wine was determined using Folin-Ciocalteau assay. The radical scavenging activity was evaluated using 2,2-diphenyl-1-picryhydrazyl (DPPH) assay. Apart from a few bottles that exhibited above average radical scavenging activity and phenolic content, there was no good correlation of those two quantities with region, price or vintage. The average phenolic amount was 2874 mg/L. The lowest phenolic content was found to be 1648 mg/L for an eight dollar wine. Wine with the highest amount of phenol of 4495 mg/L was a 2007, nine dollar bottle from South America. High amount of phenols did not translate into high radical scavenging activity. Barrel-aging did not increase the amount of phenols or the radical scavenging activity of wine. In order to discover new and potent sources of antioxidants from plants, the following spices were studied: ginger, cilantro, cumin, anise, linden, eucalyptus, marjoram, oregano, sage, thyme and rosemary. Whole spices were crushed and extracted for 96 h at room temperature using a combination of ethyl acetate, ethyl alcohol and water in the ratio of 4.5:4.5:1 (v/v/v). The radical scavenging activity of extracts was evaluated using 2,2-diphenyl-1-picryhydrazyl (DPPH) assay. The total phenolic content of each spice was also determined using the Folin-Ciocalteau assay. Eucalyptus was found to be the most potent antioxidant with an LC50 of 324.1 mg of phenol/L, followed by marjoram with an LC50 of 407.5 mg of phenol/L, and rosemary with an LC50 of 414.0 mg/L. The least potent antioxidants were ginger and cilantro with LC50 of 7604 mg/L of phenol and 7876 mg of phenol/L, respectively. PMID:26784340

  3. Determination of Radical Scavenging Activity and Total Phenols of Wine and Spices: A Randomized Study

    PubMed Central

    Lugemwa, Fulgentius Nelson; Snyder, Amanda L.; Shaikh, Koonj

    2013-01-01

    Thirty eight bottles of red wine (Carbanet Sauvignon) were randomly selected based on vintage, region, price, and age (number of months in a barrel). The total phenolic content of each wine was determined using Folin-Ciocalteau assay. The radical scavenging activity was evaluated using 2,2-diphenyl-1-picryhydrazyl (DPPH) assay. Apart from a few bottles that exhibited above average radical scavenging activity and phenolic content, there was no good correlation of those two quantities with region, price or vintage. The average phenolic amount was 2874 mg/L. The lowest phenolic content was found to be 1648 mg/L for an eight dollar wine. Wine with the highest amount of phenol of 4495 mg/L was a 2007, nine dollar bottle from South America. High amount of phenols did not translate into high radical scavenging activity. Barrel-aging did not increase the amount of phenols or the radical scavenging activity of wine. In order to discover new and potent sources of antioxidants from plants, the following spices were studied: ginger, cilantro, cumin, anise, linden, eucalyptus, marjoram, oregano, sage, thyme and rosemary. Whole spices were crushed and extracted for 96 h at room temperature using a combination of ethyl acetate, ethyl alcohol and water in the ratio of 4.5:4.5:1 (v/v/v). The radical scavenging activity of extracts was evaluated using 2,2-diphenyl-1-picryhydrazyl (DPPH) assay. The total phenolic content of each spice was also determined using the Folin-Ciocalteau assay. Eucalyptus was found to be the most potent antioxidant with an LC50 of 324.1 mg of phenol/L, followed by marjoram with an LC50 of 407.5 mg of phenol/L, and rosemary with an LC50 of 414.0 mg/L. The least potent antioxidants were ginger and cilantro with LC50 of 7604 mg/L of phenol and 7876 mg of phenol/L, respectively. PMID:26784340

  4. Evaluation of antioxidant and free radical scavenging capacities of some Nigerian indigenous medicinal plants.

    PubMed

    Akinmoladun, Afolabi C; Obuotor, Efere M; Farombi, Ebenezer O

    2010-04-01

    Methanolic extracts of 10 selected Nigerian medicinal plants-Psidium guajava, Alstonia boonei, Cassia alata, Newbouldia laevis, Spondias mombin, Globimetula cupulatum, Chromolaena odorata, Securidaca longepedunculata, Ocimum gratissimum, and Morinda lucida-widely used in ethnomedicine, were assessed for phytochemical constituents and antioxidant and free radical scavenging activities using seven different antioxidant assay methods. Phytochemical screening gave positive tests for steroids, terpenoids, and cardiac glycosides, alkaloids, saponins, tannins, and flavonoids contained in the extracts. P. guajava contained the highest amount of total phenolics (380.08 +/- 4.40 mg/L gallic acid equivalents), and the highest amounts of total flavonoids were found in the leaf extracts of C. alata (275.16 +/- 1.62 microg/mL quercetin equivalents [QE]), C. odorata (272.12 +/- 2.32 microg/mL QE), and P. guajava (269.72 +/- 2.78 microg/mL QE). Percentage 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was highest in S. mombin (88.58 +/- 3.04%) and P. guajava (82.79 +/- 2.84%) and compared with values obtained for ascorbic acid and gallic acid. All the extracts, generally, had low nitric oxide radical scavenging activities, and G. cupulatum had the highest hydroxyl radical scavenging activity (63.84 +/- 0.97%). The extracts in general demonstrated high lipid peroxidation inhibitory activity, with only M. lucida (38.74 +/- 1.99%) and A. boonei (47.16 +/- 0.59%) being exceptions. The reductive potential was highest in P. guajava (0.79 +/- 0.04) and least in S. longepedunculata (0.26 +/- 0.00). DPPH assay correlated well with total phenolic contents (r(2) = 0.76) and reductive potential (r(2) = 0.81) and fairly with lipid peroxidation inhibitory activity (r(2) = 0.51). There was a good correlation between total phenolic contents and reductive potential (r(2) = 0.79) and a fair correlation between total phenolic contents and lipid peroxidation inhibitory activity (r(2

  5. Manganese complexes and the generation and scavenging of hydroxyl free radicals.

    PubMed

    Cheton, P L; Archibald, F S

    1988-01-01

    In a wide variety of biological systems non-enzyme complexes of the metals copper (Cu) and iron (Fe) have been shown to enhance oxygen radical damage by increasing the production of an oxidative species generally believed to be the hydroxyl free radical (.OH) via "Fenton" and possibly "Haber-Weiss" type reactions. However, the behavior of the chemically and biologically similar transition metal manganese (Mn) with .OH is unknown. Unlike Fe and Cu, inorganic complexes of Mn are known to exist in high concentrations in certain cells. Three different oxygen free radical generating systems and four .OH detection methods were used to investigate the activity of biologically relevant inorganic Mn complexes. These complexes were compared to compounds reported to scavenge and generate .OH. The direct and indirect effects of Mn on the .OH flux were compared by attempting to distinguish the effects of hydrogen peroxide (H2O2), superoxide (O2-), and .OH through the use of selective scavengers and generators. Mn-EDTA and biologically relevant Mn-pyrophosphates and polyphosphates, in contrast to Fe-EDTA, do not generate .OH in these systems. The results suggest that Mn in various forms does, indeed, inhibit oxy-radical damage mediated by .OH, but only if the .OH production is dependent on the presence of O2- or H2O2. Thus, with .OH, as with O2- and H2O2, Mn complexes appear to behave in a fundamentally different fashion from Cu and Fe. PMID:2855733

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

    PubMed

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

    2016-01-01

    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. PMID:27526125

  7. Fenton-like degradation of MTBE: Effects of iron counter anion and radical scavengers.

    PubMed

    Hwang, Sangchul; Huling, Scott G; Ko, Saebom

    2010-01-01

    Fenton-driven oxidation of methyl tert-butyl ether (MTBE) (0.11-0.16mM) in batch reactors containing ferric iron (5mM) and hydrogen peroxide (H(2)O(2)) (6mM) (pH=3) was performed to investigate MTBE transformation mechanisms. Independent variables included the forms of iron (Fe) (Fe(2)(SO(4))(3).9H(2)O and Fe(NO(3))(3).9H(2)O), H(2)O(2) (6, 60mM), chloroform (CF) (0.2-2.4mM), isopropyl alcohol (IPA) (25, 50mM), and sulfate (7.5mM). MTBE, tert-butyl alcohol and acetone transformation were significantly greater when oxidation was carried out with Fe(NO(3))(3).9H(2)O than with Fe(2)(SO(4))(3).9H(2)O. Sulfate interfered in the formation of the ferro-peroxy intermediate species, inhibited H(2)O(2) reaction, hydroxyl radical (()OH) formation, and MTBE transformation. Transformation was faster and more complete at a higher [H(2)O(2)] (60mM), but resulted in lower oxidation efficiency which was attributed to ()OH scavenging by H(2)O(2). CF scavenging of the superoxide radical (()O(2)(-)) in the ferric nitrate system resulted in lower rates of ()O(2)(-) reduction of Fe(III) to Fe(II), ()OH production, and consequently lower rates of MTBE transformation. IPA, an excellent scavenger of ()OH, completely inhibited MTBE transformation in the ferric nitrate system indicating oxidation was predominantly by ()OH. ()OH scavenging by HSO(4)(-), formation of the sulfate radical (()SO(4)(-)), and oxidation of MTBE by ()SO(4)(-) was estimated to be negligible. The form of Fe (i.e., counter anion) selected for use in Fenton treatment systems impacts oxidative mechanisms, treatment efficiency, and post-oxidation treatment of residuals which may require additional handling and cost. PMID:19959205

  8. Effects of radical scavengers on aqueous solutions exposed to heavy-ion irradiation using the liquid microjet technique

    NASA Astrophysics Data System (ADS)

    Nomura, Shinji; Tsuchida, Hidetsugu; Furuya, Ryousuke; Miyahara, Kento; Majima, Takuya; Itoh, Akio

    2015-12-01

    The effects of the radical scavenger ascorbic acid on water radiolysis are studied by fast heavy-ion irradiation of aqueous solutions of ascorbic acid, using the liquid microjet technique under vacuum. To understand the reaction mechanisms of hydroxyl radicals in aqueous solutions, we directly measure secondary ions emitted from solutions with different ascorbic acid concentrations. The yield of hydronium secondary ions is strongly influenced by the reaction between ascorbic acid and hydroxyl radicals. From analysis using a simple model considering chemical equilibria, we determine that the upper concentration limit of ascorbic acid with a radical scavenger effect is approximately 70 μM.

  9. How Do Nutritional Antioxidants Really Work: Nucleophilic Tone and Para-Hormesis Versus Free Radical Scavenging in vivo

    PubMed Central

    Forman, Henry Jay; Davies, Kelvin J. A.; Ursini, Fulvio

    2013-01-01

    We present arguments for an evolution in our understanding of how antioxidants in fruits and vegetables exert their health-protective effects. There is much epidemiological evidence for disease prevention by dietary antioxidants and chemical evidence that such compounds react in one-electron reactions with free radicals in vitro. Nonetheless, kinetic constraints indicate that in vivo scavenging of radicals is ineffective in antioxidant defense. Instead, enzymatic removal of non-radical electrophiles, such as hydroperoxides, in two-electron redox reactions is the major antioxidant mechanism. Furthermore, we propose that a major mechanism of action for nutritional antioxidants is the paradoxical oxidative activation of the Nrf2 (NF-E2-related factor 2) signaling pathway, which maintains protective oxidoreductases and their nucleophilic substrates. This maintenance of ‘Nucleophilic Tone,’ by a mechanism that can be called ‘Para-Hormesis,’ provides a means for regulating physiological non-toxic concentrations of the non-radical oxidant electrophiles that boost antioxidant enzymes, and damage removal and repair systems (for proteins, lipids, and DNA), at the optimal levels consistent with good health. PMID:23747930

  10. Modeling the mechanism of action of lycopene as a hydroxyl radical scavenger.

    PubMed

    Prasad, Ajit Kumar; Mishra, Phool C

    2014-05-01

    The anti-oxidant action of lycopene as a hydroxyl radical scavenger through hydrogen abstraction and addition reaction mechanisms has been investigated. Geometries of seven different conformations of lycopene were optimized employing density functional theory in gas phase which was followed by treatment of their solvation in aqueous media. Thus the all-trans conformation of lycopene was found to be most stable in both gas phase and aqueous media. Four overlapping fragments of all-trans lycopene were considered for calculations of Gibbs barrier energies and rate constants. It is found that several hydrogen atoms can be abstracted from lycopene by a hydroxyl radical barrierlessly. Further, it is shown that addition of an OH radical can also take place to each of the various carbon atoms of lycopene with fairly low barrier energies. Thus lycopene is shown to be an effective anti-oxidant. PMID:24777316

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

    NASA Astrophysics Data System (ADS)

    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.

  12. Free-radical scavengers and antioxidants from Peumus boldus Mol. ("Boldo").

    PubMed

    Schmeda-Hirschmann, G; Rodriguez, J A; Theoduloz, C; Astudillo, S L; Feresin, G E; Tapia, A

    2003-04-01

    The dry leaves of Peumus boldus (Monimiaceae) are used in infusion or decoction as a digestive and to improve hepatic complains. Preliminary assays showed free-radical scavenging activity in hot water extracts of boldo leaves, measured by the decoloration of a methanolic solution of the 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH). Assay-guided isolation led to the active compounds. Catechin proved to be the main free-radical scavenger of the extracts. Lipid peroxidation in erythrocytes was inhibited by boldo extracts and fractions at 500 microg/ml with higher effect for the ethyl acetate soluble and alkaloid fractions. The IC50 for catechin and boldine in the lipid peroxidation test were 75.6 and 12.5 microg/ml, respectively. On the basis of dry starting material the catechin content in the crude drug was 2.25% while the total alkaloid calculated as boldine was 0.06%. The activity of boldine was six times higher than catechin in the lipid peroxidation assay. However, the mean catechin:total alkaloid content ratio was 37:1. The relative concentration of alkaloids and phenolics in boldo leaves and their activity suggest that free-radical scavenging effect is mainly due to catechin and flavonoids and that antioxidant effect is mainly related with the catechin content The high catechin content of boldo leaves and its bioactivity suggest that quality control of Boldo folium has to combine the analysis of catechin as well as their characteristic aporphine alkaloids. PMID:12747739

  13. Iron-reducing and free-radical-scavenging properties of apomorphine and some related benzylisoquinolines.

    PubMed

    Ubeda, A; Montesinos, C; Payá, M; Alcaraz, M J

    1993-08-01

    The scavenging and iron-reducing properties of a series of benzylisoquinolines of natural and synthetic origin have been studied. Bulbocapnine, boldine, glaucine, and stepholidine acted as scavengers of hydroxyl radical in the deoxyribose degradation by Fe(3+)-EDTA + H2O2. On the contrary, laudanosoline, apomorphine, protopapaverine, anonaine, and tetrahydroberberine increased deoxyribose degradation by a mechanism related to generation of superoxide anion. Only apomorphine had a stimulating effect in the system using citrate instead of ethylenediaminetetraacetic acid (EDTA) as well as in the absence of chelator. Apomorphine also stimulated DNA damage by Cu2+. The iron-ion reducing ability of apomorphine and laudanosoline was confirmed using cytochrome c. Both compounds scavenged peroxyl radicals in an aqueous medium, while in Fe(3+)-induced microsomal lipid peroxidation apomorphine acted as an inhibitor and laudanosoline stimulated the process. It is suggested that in microsomes the chain-breaking antioxidant properties of apomorphine overcome its possible influence on redox cycling of iron, or prooxidant properties. PMID:8397141

  14. Free radical scavengers and antioxidants from Lemongrass (Cymbopogon citratus (DC.) Stapf.).

    PubMed

    Cheel, José; Theoduloz, Cristina; Rodríguez, Jaime; Schmeda-Hirschmann, Guillermo

    2005-04-01

    Methanol, MeOH/water extracts, infusion, and decoction of Cymbopogon citratus were assessed for free radical scavenging effects measured by the bleaching of the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical, scavenging of the superoxide anion, and inhibition of the enzyme xanthine oxidase (XO) and lipid peroxidation in human erythrocytes. The extracts presented effect in the DPPH and superoxide anion assay, with values ranging between 40 and 68% and 15-32% at 33 and 50 microg/mL, respectively, inhibited lipid peroxidation in erythrocytes by 19-71% at 500 microg/mL and were inactive toward the XO at 50 microg/mL. Isoorientin, isoscoparin, swertiajaponin, isoorientin 2' '-O-rhamnoside, orientin, chlorogenic acid, and caffeic acid were isolated and identified by spectroscopic methods. Isoorientin and orientin presented similar activities toward the DPPH (IC(50): 9-10 microM) and inhibited lipid peroxidation by 70% at 100 microg/mL. Caffeic and chlorogenic acid were active superoxide anion scavengers with IC(50) values of 68.8 and 54.2 microM, respectively, and a strong effect toward DPPH. Caffeic acid inhibited lipid peroxidation by 85% at 100 microg/mL. PMID:15796587

  15. Assessment of Free Radical Scavenging Potential and Oxidative DNA Damage Preventive Activity of Trachyspermum ammi L. (Carom) and Foeniculum vulgare Mill. (Fennel) Seed Extracts

    PubMed Central

    2014-01-01

    Oxidation of biomolecules such as carbohydrates, proteins, lipids, and nucleic acids results in generation of free radicals in an organism which is the major cause of onset of various degenerative diseases. Antioxidants scavenge these free radicals, thereby protecting the cell from damage. The present study was designed to examine the free radical scavenging potential and oxidative DNA damage preventive activity of traditionally used spices Trachyspermum ammi L. (carom) and Foeniculum vulgare Mill. (fennel). The aqueous, methanolic, and acetonic extracts of T. ammi and F. vulgare seeds were prepared using soxhlet extraction assembly and subjected to qualitative and quantitative estimation of phytochemical constituents. Free radical scavenging potential was investigated using standard methods, namely, DPPH radical scavenging assay and ferric reducing antioxidant power assay along with the protection against oxidative DNA damage. The results stated that acetonic seed extracts (AAcSE and FAcSE) of both the spices possessed comparatively high amount of total phenolics whereas methanolic seed extracts (AMSE and FMSE) were found to have highest amount of total flavonoids. At 1 mg/mL concentration, highest DPPH radical scavenging activity was shown by FMSE (96.2%), AAcSE was recorded with highest FRAP value (2270.27 ± 0.005 μmol/L), and all the seed extracts have been shown to mitigate the damage induced by Fenton reaction on calf thymus DNA. Therefore, the study suggests that T. ammi and F. vulgare seed extracts could contribute as a highly significant bioresource of antioxidants to be used in our day-to-day life and in food and pharmaceutical industry. PMID:25143939

  16. Characterization of the superoxide anion radical scavenging activity by tetracycline antibiotics in aprotic media.

    PubMed

    Kładna, Aleksandra; Kruk, Irena; Michalska, Teresa; Berczyński, Paweł; Aboul-Enein, Hassan Y

    2011-01-01

    The tetracycline family antibiotics are widely used as human and veterinary treatments. The drugs are effective as antibiotics and also show antimicrobial and non-microbial action. However, the antioxidant properties of tetracyclines have not been characterized in aprotic media. To better understand their biological functions, the in vitro superoxide anion radical (O2•¯) scavenging activities of tetracycline, chlortetracycline, oxytetracycline, doxycycline and methacycline were characterized, along with a very efficient O2•¯ scavenger, tiron, in dimethyl sulphoxide (DMSO), using ultra-weak chemiluminescence (CL). We found that tetracycline, chlortetracycline and doxycycline efficiently inhibited CL from the O2•¯-generating system at concentration levels of 0.02-1.0 mmol/L. Methacycline and oxytetracycline were the O2•¯ scavengers at concentration levels of 0.01-0.1 mmol/L, whereas when their concentration was lowered the drugs were capable of generating O2•¯, leading to CL enhancement. For all the data obtained in this study, the scavenging activity for the compounds tested decreased in the following order: tetracycline > doxycycline > chlortetracycline > tiron methacycline > oxytetracycline. These results indicate that the tetracycline drugs directly alter O2•¯ redox chemistry in aprotic media. PMID:21413138

  17. Development of a triple hyphenated HPLC-radical scavenging detection-DAD-SPE-NMR system for the rapid identification of antioxidants in complex plant extracts.

    PubMed

    Pukalskas, Audrius; van Beek, Teris A; de Waard, Pieter

    2005-05-13

    A rapid method for the simultaneous detection and identification of radical scavenging compounds in plant extracts was developed by combining an HPLC with on-line radical scavenging using DPPH* as a model radical and an HPLC-DAD-SPE-NMR system. Using this method a commercial rosemary extract was investigated. All major compounds present in the extract were collected on SPE cartridges after their separation. Advantages of on-line SPE peak trapping are the possibility to perform HPLC with non-deuterated solvents, a concentration effect and being able to record NMR spectra in pure 100% deuterated solvents. After comparing DAD and DPPH scavenging chromatograms, 1H NMR spectra of compounds having radical scavenging activities were recorded. Afterwards all compounds were collected and infused into an ESI-MS. The five main active compounds - carnosol, carnosic acid carnosaldehyde, 12-methoxycarnosic acid and epiisorosmanol could be identified from the combined UV, NMR and mass spectral data without actually isolating them. It was possible to record on-line an HMBC spectrum of carnosic acid. Also one compound was tentatively identified as epirosmanol methyl ether. PMID:15941042

  18. Free radical scavenging actions of hippocampal metallothionein isoforms and of antimetallothioneins: an electron spin resonance spectroscopic study.

    PubMed

    Kumari, M V; Hiramatsu, M; Ebadi, M

    2000-05-01

    The high concentration of zinc in the hippocampal mossy fiber axon boutons is localized in the vesicles and is mobilized by exocytosis of the zinc-laden vesicles. Furthermore, the mammalian hippocampi contain metallothionein (MT) isoforms which regulate the steady state concentration of zinc, an important antioxidant. Indeed, zinc deprivation leads to an increased lipid peroxidation, reduces the activity of Cu++-Zn++ superoxide dismutase, and protect against oxidative stress such as exposure to ultraviolet A irradiation. By employing electron spin resonance (ESR) spectroscopy, we have demonstrated that rat hippocampal MT isoforms 1 and 2 were able to scavenge 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH), hydroxyl radicals (*OH) generated in a Fenton reaction, and superoxide anions (O2*-) generated by the hypoxanthine and xanthine oxidase system. In addition, MT-1 isoform protected the isolated hepatocytes from lipid peroxidation as determined by thiobarbituric acid bound malondialdehyde. MT antibodies scavenged DPPH radicals, hydroxyl radicals and reactive oxygen species but not superoxide anions. The results of these studies suggest that although both isoforms of MT are able to scavenge free radicals, the MT-1 appears to be a superior scavenger of superoxide anions and 1,1-diphenyl-2-picrylhydrazyl radicals. Moreover, antibodies formed against MT isoform retain some, but not all, free radical scavenging actions exhibited by MT-1 and MT-2. PMID:10872749

  19. DPPH radical-scavenging effect on some constituents from the aerial parts of Lippia triphylla.

    PubMed

    Ono, Masateru; Oda, Eriko; Tanaka, Takemi; Iida, Yoshihiko; Yamasaki, Toru; Masuoka, Chikako; Ikeda, Tsuyoshi; Nohara, Toshihiro

    2008-01-01

    Lippia triphylla (L'HER) O. KUNTZE: (Verbenaceae; common name, Lemon Verbena) is used in Peru as a spice and herb tea for the prevention of arteriosclerosis. From the aerial parts of this plant, 25 known compounds--3 phenylpropanoid glucosides, 7 flavonoids, 5 phenylethanoid glycosides, 5 lignans, 2 sesquiterpenoids, and 3 triterpenoids--were isolated, and their chemical structures were elucidated on the basis of physical and spectral data. Among them, 19 aromatic compounds were examined for their scavenging effect on the stable free radical 1,1-diphenyl-2-picrylhydrazyl--4 phenylethanoid glycosides and 5 lignans indicated a potent scavenging effect. Of note, the EC(50) values of two phenylethanoid glycosides reached almost thrice that of alpha-tocopherol. PMID:18404353

  20. Radical scavenging activity and composition of raspberry (Rubus idaeus) leaves from different locations in Lithuania.

    PubMed

    Venskutonis, P R; Dvaranauskaite, A; Labokas, J

    2007-02-01

    Raspberry (Rubus idaeus) leaves, collected in different locations of Lithuania were extracted with ethanol and the extracts were tested for their antioxidant activity (AA) by using ABTS(.)(+) decolourisation and DPPH(.) scavenging methods. All extracts were active, with radical scavenging capacity at the used concentrations from 20.5 to 82.5% in DPPH(.) reaction system and from 8.0 to 42.7% in ABTS(.)(+) reaction. The total amount of phenolic compounds in the leaves varied from 4.8 to 12.0 mg of gallic acid equivalents (GAE) in 1 g of plant extract. Quercetin glucuronide, quercetin-3-O-glucoside and rutin were identified in the extracts. PMID:17215088

  1. Monoamine oxidase B and free radical scavenging activities of natural flavonoids in Melastoma candidum D. Don.

    PubMed

    Lee, M H; Lin, R D; Shen, L Y; Yang, L L; Yen, K Y; Hou, W C

    2001-11-01

    Monoamine oxidase type B (MAO-B) activity and free radicals are elevated in certain neurological diseases. Four natural flavonoids, quercitrin, isoquercitrin, rutin, and quercetin, were isolated for the first time from the leaves of Melastoma candidum D. Don. They exhibited an inhibitory effect on MAO-B. These potent flavonoids were purified using bioassay-guided fractionation and were separated by Diaion, Sephadex LH-20, and MCI CHP20P columns. The IC(50) values of the four potent flavonoids, quercitrin, isoquercitrin, rutin, and quercetin on monoamine oxidase were 19.06, 11.64, 3.89, and 10.89 microM and enzyme kinetics analysis revealed apparent inhibition constants (K(i)) of 21.01, 2.72, 1.83, and 7.95 microM, respectively, on the substrate, benzylamine. The four potent compounds also exhibited hydroxyl radical scavenging activity as determined using a spin trapping electron spin resonance method. This suggests that the four flavonoids from M. candidum possess both MAO-B inhibitory and free radical scavenging activities. These important properties may be used for preventing some neurodegenerative diseases in the future. PMID:11714358

  2. Antioxidant, Antimicrobial, and Free Radical Scavenging Potential of Aerial Parts of Periploca aphylla and Ricinus communis

    PubMed Central

    Iqbal, Jamshed; Zaib, Sumera; Farooq, Umar; Khan, Afsar; Bibi, Irum; Suleman, Saba

    2012-01-01

    Context. Many diseases are associated with oxidative stress caused by free radicals. Objective. The present study evaluated the in vitro antioxidant and antibacterial activities of various extracts of aerial parts of Periploca aphylla and Ricinus communis. Materials and Methods. In vitro antioxidant activities of the plant extract were determined by DPPH and NO scavenging method. Superoxide anion radical activity was measured by the reduction of nitro blue tetrazolium as compared with standard antioxidants. Total phenolic contents and antibacterial activities of these plants were determined by gallic acid equivalent (GAE) and serial tube dilution method, respectively. Results. Plants showed significant radical scavenging activity. The results were expressed as IC50. n-Propyl gallate and 3-t-butyl-4-hydroxyanisole were used as standards for antioxidant assay. All the extracts of both plants showed comparable IC50 to those of standards. Plants extract exhibited high phenolic contents and antibacterial activities were comparable with standard drug, Ciprofloxacin. Discussion and Conclusion. The present study provides evidence that Periploca aphylla and Ricinus communis prove to be potent natural antioxidants and could replace synthetic antioxidants. Plants can also be used against pathogenic bacterial strains. PMID:22919511

  3. Essential Oil from Flowers and Leaves of Elaeagnus Angustifolia (Elaeagnaceae): Composition, Radical Scavenging and General Toxicity Activities

    PubMed Central

    Torbati, Mohammadali; Asnaashari, Solmaz; Heshmati Afshar, Fariba

    2016-01-01

    Purpose: The aim of this work was to identify the chemical composition of the essential oils obtained from the flowers and leaves of Elaeagnus angostifolia (Elaeagnaceae) along with evaluate the radical scavenging and general toxicity activities. Methods: A combination of GC-MS and GC-FID were utilized for analyzing the chemical profile of the essential oils extracted by hydro-distillation from the leaves and flowers of E. angustifolia. The essential oils were subjected to general toxicity and radical scavenging assays using brine shrimp lethality test and DPPH method, respectively. Results: In total, 53 and 25 components were identified and quantified in the essential oils of flowers and leaves, accounting for 96.59% and 98.97% of the oil, respectively. The both oils were observed to be rich in ester compounds. The most abundant components of the oil from flowers were E-ethyl cinnamate (60.00%), hexahydrofarnesyl acetone (9.99%), palmitic acid (5.20%) and phytol (3.29%). The major constituents of the oil from leaves were E-ethyl cinnamate (37.27%), phytol (12.08%), nonanal (10.74%) and Z-3-hexenyl benzoate (7.65%). Both oils showed moderate activity in DPPH assay; however, they exhibited potent tocixity in brine shrimp lethality test. Conclusion: The remarkable toxicity effects of the oils are worthy to further investigation to find the probable mechanisms of action accountable for the noticeable toxic effect of these essential oils. PMID:27478777

  4. Enhanced DPPH radical scavenging activity and DNA protection effect of litchi pericarp extract by Aspergillus awamori bioconversion

    PubMed Central

    2012-01-01

    Background Litchi (Litchi chinensis Sonn.) pericarp is a major byproduct which contains a significant amount of polyphenol. This study was designed to biotransformation litchi pericarp extract (LPE) by Aspergillus awamori to produce more bioactive compounds with stronger antioxidant activities. Results The study exhibited that the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activities significantly (p < 0.05) increased from 15.53% to 18.23% in the water-extracted fraction and from 25.41% to 36.82% in the ethyl acetate-extracted fraction. Application of DNA cleavage assay further demonstrated the enhanced protection effect of the fermented phenolics on DNA damage. It is also noted that the water-extracted fraction of the fermented LPE possessed a much stronger capacity than the ethyl acetate-extracted fraction to prevent from damage of supercoiled DNA. Interestingly, it was found that some new compounds such as catechin and quercetin appeared after of A. awamori fermentation of LPE, which could account for the enhanced antioxidant activity. Conclusion The DPPH radical scavenging activity and DNA protection effect of LPE were increased by Aspergillus awamori bioconversion while some compounds responsible for the enhanced antioxidant activity were identified. This study provided an effective way of utilizing fruit pericarp as a readily accessible source of the natural antioxidants in food industry and, thus, extended the application area such as fruit by-products. PMID:23016522

  5. Effects of Different Drying Methods and Storage Time on Free Radical Scavenging Activity and Total Phenolic Content of Cosmos caudatus

    PubMed Central

    Mediani, Ahmed; Abas, Faridah; Tan, Chin Ping; Khatib, Alfi

    2014-01-01

    The present study was conducted to determine the effect of air (AD), oven (OD) and freeze drying (FD) on the free radical scavenging activity and total phenolic content (TPC) of Cosmos caudatus and the effect of storage time by the comparison with a fresh sample (FS). Among the three drying methods that were used, AD resulted in the highest free radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) (IC50 = 0.0223 mg/mL) and total phenolic content (27.4 g GAE/100 g), whereas OD produced the lowest scavenging activity and TPC value. After three months of storage, the dried samples showed a high and consistent free radical scavenging activity when compared to stored fresh material. The drying methods could preserve the quality of C. caudatus during storage and the stability of its bioactive components can be maintained. PMID:26784876

  6. A new antimicrobial and radical-scavenging glycoside from Paullinia pinnata var. cameroonensis.

    PubMed

    Lunga, Paul-Keilah; Qin, Xu-Jie; Yang, Xing-Wei; Kuiate, Jules-Roger; Du, Zhi-Zhi; Gatsing, Donatien

    2015-01-01

    A new glycoside, pinnatoside A (1), together with two known compounds (2 and 3), were isolated from the stems of Paullinia pinnata. Their structures were elucidated on the basis of extensive spectroscopic analysis and chemical methods. Compound 1 showed significant antibacterial activity with a minimum inhibitory concentration (MIC) value of 1.56 μg/mL against Escherichia coli, and 2 displayed significant antibacterial activity with a MIC value of 1.56 μg/mL against Enterobacter aerogenes and E. coli. Equally, compound 1 exhibited the best radical-scavenging activity (RSa50 = 25.07 ± 0.49 μg/mL). PMID:25563339

  7. Green Synthesis of Bifunctional Fluorescent Carbon Dots from Garlic for Cellular Imaging and Free Radical Scavenging.

    PubMed

    Zhao, Shaojing; Lan, Minhuan; Zhu, Xiaoyue; Xue, Hongtao; Ng, Tsz-Wai; Meng, Xiangmin; Lee, Chun-Sing; Wang, Pengfei; Zhang, Wenjun

    2015-08-12

    Nitrogen and sulfur codoped carbon dots (CDs) were prepared from garlic by a hydrothermal method. The as-prepared CDs possess good water dispersibility, strong blue fluorescence emission with a fluorescent quantum yield of 17.5%, and excellent photo and pH stabilities. It is also demonstrated that the fluorescence of CDs are resistant to the interference of metal ions, biomolecules, and high ionic strength environments. Combining with low cytotoxicity properties, CDs could be used as an excellent fluorescent probe for cellular multicolor imaging. Moreover, the CDs were also demonstrated to exhibit favorable radical scavenging activity. PMID:26193082

  8. LC/PDA/ESI-MS Profiling and Radical Scavenging Activity of Anthocyanins in Various Berries.

    PubMed

    Nakajima, Jun-Ichiro; Tanaka, Ippei; Seo, Shujiro; Yamazaki, Mami; Saito, Kazuki

    2004-01-01

    Anthocyanin extracts of two blueberries, Vaccinium myrtillus (bilberry) and Vaccinium ashei (rabbiteye blueberry), and of three other berries, Ribes nigrum (black currant), Aronia melanocarpa (chokeberry), and Sambucus nigra (elderberry), were analyzed by high-performance liquid chromatography coupled with photodiode array detection and electrospray ionization - mass spectrometry (LC/PDA/ESI-MS). Both bilberry and rabbiteye blueberry contained 15 identical anthocyanins with different distribution patterns. Black currant, chokeberry, and elderberry contained 6, 4, and 4 kinds of anthocyanins, respectively. The radical scavenging activities of these berry extracts were analyzed by using 2,2-diphenyl-1-picrylhydrazyl (DPPH). All these extracts showed potent antiradical activities. PMID:15577184

  9. Effects of gamma irradiation on total polyphenols, radical scavenging activities and decolourization of Nelumbo nucifera extracts

    NASA Astrophysics Data System (ADS)

    Jeong, Il Yun; Lee, Hyo Jung; Park, Yong Dae; Jin, Chang Hyun; Choi, Dae Seong; Byun, Myung Woo

    2009-07-01

    The ethanolic leaf extract of Nelumbo nucifera (NC) was exposed to γ-irradiation, and its antioxidant activities, total polyphenols and colour characteristics were studied to discern its potential ability as a food or cosmetic materials. The results demonstrated that the radical scavenging activities and total polyphenols of the γ-irradiated leaf extract of NC were not observed to be significantly different. However, γ-irradiation significantly increased the Hunter colour L*-value at doses of 20 and 50 kGy, while the Hunter colour b*-values were decreased under the same conditions.

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

    NASA Astrophysics Data System (ADS)

    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.

  11. Differential effect of denervation on free radical scavenging enzymes in slow and fast muscle of rat

    NASA Technical Reports Server (NTRS)

    Asayama, K.; Dettbarn, W. D.; Burr, I. M.

    1985-01-01

    To determine the effect of denervation on the free radical scavenging systems in relation to the mitochondrial oxidative metabolism in the slow twitch soleus and fast twitch extensor digitorum longus (EDL) muscles, the sciatic nerve of the rat was crushed in the mid-thigh region and the muscle tissue levels of 5 enzymes were studied 2 and 5 weeks following crush. Radioimmunoassays were utilized for the selective measurement of cuprozinc (cytosolic) and mangano (mitochondrial) superoxide dismutases. These data represent the first systematic report of free radical scavening systems in slow and fast muscles in response to denervation. Selective modification of cuprozinc and manganosuperoxide dismutases and differential regulation of GSH-peroxidase was demonstrated in slow and fast muscle.

  12. The Scavenging of DPPH, Galvinoxyl and ABTS Radicals by Imine Analogs of Resveratrol

    PubMed Central

    Kotora, Peter; Šeršeň, František; Filo, Juraj; Loos, Dušan; Gregáň, Juraj; Gregáň, Fridrich

    2016-01-01

    Resveratrol (3,5,4′-trihydroxystilbene) is a phytoalexin produced by plants. Resveratrol is known for its anti-cancer, antiviral and antioxidant properties. We prepared imine analogs of resveratrol ((hydroxyphenyliminomethyl)phenols) and tested their antioxidant activity. All prepared resveratrol analogs were able to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH), galvinoxyl radical (GOR) and 2,2′-azino-bis(3-ethylbenzothiazoline)-6-sulphonic acid (ABTS) radicals. The antioxidant activity efficiency correlated with the number and position of hydroxyl groups. The most effective antioxidants were resveratrol analogs containing three hydroxyl groups in the benzylidene part of their molecules. These results provide new insights into the relationship between the chemical structure and biological activity of resveratrol analogs. PMID:26805801

  13. Design and evaluation of 4-aminophenol and salicylate derivatives as free-radical scavenger.

    PubMed

    Borges, Rosivaldo S; Pereira, Glaécia A N; Vale, Joyce K L; França, Luiz C S; Monteiro, Marta C; Alves, Cláudio N; da Silva, Albérico B F

    2013-03-01

    This theoretical and experimental study describes the design and evaluation of the free-radical scavenging effect for the molecular association of 4-aminophenol and salicylate derivatives. For this purpose, we employed theoretical methods for the selection of antioxidant drugs and the rapid methods of evaluation: the 1,1-diphenyl-2-picrylhydrazyl radical and the thiobarbituric acid reactive substances in the lipid peroxidation initiated by Fe(2+) and ascorbic acid in human erythrocytes. The associate derivatives exhibited a more potent inhibition than the salicylic acid, while the benzoyl compound exhibited a more potent inhibition than paracetamol. The molecular parameters related to the electron distribution and structure (ionization potential and energy of the highest occupied molecular orbital) correlated very well with the antioxidant action of the compounds studied here in different tests. PMID:23405943

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

    PubMed

    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. PMID:25835071

  15. Antimicrobial and free radical scavenging activities of five Palestinian medicinal plants.

    PubMed

    Qabaha, Khaled Ibraheem

    2013-01-01

    Extracts from five indigenous Palestinian medicinal plants including Rosmarinus officinalis, Pisidium guajava, Punica granatum peel, grape seeds and Teucrium polium were investigated for antimicrobial and free radical scavenging activities against eight microorganisms, using well diffusion method. The microorganisms included six bacterial isolates (i.e. Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginos, Klebsiella pneumonia, Bacillus subtilis and Micrococcus luteus) and two fungal isolates (i.e. Candida albicans and Aspergillus niger). A standard antioxidant assay was performed on the plant extracts to assess their capability in scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH). Of the five tested plant extract, only Rosmarinus offcinalis extract contained significant antimicrobial activity against all eight microbial isolates including Pseudomonas aeruginosa. Extracts from other four plants exhibited a variable antimicrobial activity against all microorganisms, except Pseudomonas aeruginosa. Significant antioxidant activity was detected in all plant extracts. However, extracts from Pisidium guajava leaves contained significantly higher antioxidant activity compared to the other extracts tested. The antimicrobial and scavenging activities detected in this in vitro study in extracts from the five Palestinian medicinal plants suggest that further study is needed to identify active compounds to target diseases caused by a wide-spectrum pathogens. PMID:24146509

  16. Insights in the radical scavenging mechanism of syringaldehyde and generation of its anion

    NASA Astrophysics Data System (ADS)

    Yancheva, D.; Velcheva, E.; Glavcheva, Z.; Stamboliyska, B.; Smelcerovic, A.

    2016-03-01

    The ability of syringaldehyde, a naturally occurring phenolic antioxidant and medicinally important compound, to scavenge free radicals according different mechanisms was elucidated by computing the respective reaction enthalpies at DFT B3LYP/6-311++G** level. Bond dissociation enthalpy, ionization potentials and proton affinities were calculated in gas phase, benzene, water and DMSO in order to account for different environment (nonpolar lipid membranes and polar physiological liquids) where the antioxidant action in the living organism could take place and various experimental in vitro conditions. Molecular and electronic properties influencing the reactivity of syringaldehyde according to the different mechanisms were discussed in the light of the reported radical scavenging activities in crocin bleaching, oxidation potential of the first anodic peak and DPPH test. According to the calculated reaction enthalpies, in polar environment the syringaldehyde reacts preferably by sequential proton loss electron transfer which is related to the formation of a phenoxy anion. Such phenoxy anion was generated in DMSO solution and the changes in the force field, steric and electronic structure, resulting from the conversion, were described in detail based on the IR spectral data and DFT computations.

  17. Enzyme inhibitory and radical scavenging effects of some antidiabetic plants of Turkey

    PubMed Central

    Orhan, Nilüfer; Hoçbaç, Sanem; Orhan, Didem Deliorman; Asian, Mustafa; Ergun, Fatma

    2014-01-01

    Objective(s): Ethnopharmacological field surveys demonstrated that many plants, such as Gentiana olivieri, Helichrysum graveolens, Helichrysum plicatum ssp. plicatum, Juniperus oxycedrus ssp. oxycedrus, Juniperus communis var. saxatilis, Viscum album (ssp. album, ssp. austriacum), are used as traditional medicine for diabetes in different regions of Anatolia. The present study was designed to evaluate the in vitro antidiabetic effects of some selected plants, tested in animal models recently. Materials and Methods: α-glucosidase and α-amylase enzyme inhibitory effects of the plant extracts were investigated and Acarbose was used as a reference drug. Additionally, radical scavenging capacities were determined using 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) ABTS radical cation scavenging assay and total phenolic content of the extracts were evaluated using Folin Ciocalteu method. Results: H. graveolens ethanol extract exhibited the highest inhibitory activity (55.7 % ± 2.2) on α-amylase enzyme. Additionally, J. oxycedrus hydro-alcoholic leaf extract had potent α-amylase inhibitory effect, while the hydro-alcoholic extract of J. communis fruit showed the highest α-glucosidase inhibitory activity (IC50: 4.4 μg/ml). Conclusion: Results indicated that, antidiabetic effect of hydro-alcoholic extracts of H. graveolens capitulums, J. communis fruit and J. oxycedrus leaf might arise from inhibition of digestive enzymes. PMID:25140204

  18. An organoselenium drug with antioxidant activity and free radical scavenging capacity in vitro.

    PubMed

    Ibrahim, Mohammad; Hassan, Waseem; Deobald, Anna Maria; Braga, Antonio Luis; Rocha, Joao B T

    2012-12-01

    Organoselenum compounds have been reported to have a wide range of pharmacological properties. Amine-based diselenide, (Z)-N-(4-methylbenzylidene)-1-(2-((2-(1-((E)-4-methyl benzylideneamino)ethyl)phenyl)diselanyl)phenyl)ethanamine ethyl)phenyl) diselanyl) phenyl) ethylimino) methyl)phenol (compound A), and diphenyl diselenide (PhSe)2 were screened for in vitro antioxidant activity. Compound A and (PhSe)2 were tested against sodium nitroprusside (SNP)- and Fe(II)-induced thiobarbituric acid-reactive species (TBARS) in rat brain homogenates. The radical scavenging activity was measured by 1,1-diphenyl-2-picrylhydrazyl assay. Both compounds A and (PhSe)2 decreased Fe(II)- and SNP-stimulated TBARS production in rat brain homogenates. Compound A exhibited the strongest antioxidant activity in the radical scavenging assay, although (PhSe)2, the simplest of the diaryl diselenide, presented no activity. In conclusion, the results of the present investigation indicated that compound A and (PhSe)2 had preventive effects against SNP- and Fe(II)-induced oxidative stress in rat brain homogenates. The amine group in the organic moiety dramatically changed the potency of amine-based diselenide. PMID:22562597

  19. Synthesis, Characterization, Antimicrobial Screening and Free-Radical Scavenging Activity of Some Novel Substituted Pyrazoles.

    PubMed

    Hamada, Nagwa Mohamed Mahrous; Abdo, Nadia Yousef Megally

    2015-01-01

    The present work deals with the synthesis of acetoxysulfonamide pyrazole derivatives, substituted 4,5-dihydropyrazole-1-carbothioamide and 4,5-dihydropyrazole-1-isonicotinoyl derivatives starting from substituted vanillin chalcones. Acetoxysulfonamide pyrazole derivatives were prepared from the reaction of chalcones with p-sulfamylphenylhydrazine followed by treatment with acetic anhydride. At the same time 4,5-dihydropyrazole-1-carbothioamide and 4,5-dihydropyrazole-1-isonicotinoyl derivatives were prepared from the reaction of chalcones with either thiosemicarbazide or isonicotinic acid hydrazide, respectively. The synthesized compounds were structurally characterized on the basis of IR, 1H-NMR, 13C-NMR spectral data and microanalyses. All of the newly isolated compounds were tested for their antimicrobial activities. The antimicrobial screening using the agar well-diffusion method revealed that the chloro derivatives are the most active ones. Moreover, the antioxidant and anti-inflammatory activity of these chloro derivatives are also studied using the DPPH radical scavenging and NO radical scavenging methods, respectively. PMID:26060913

  20. Nutrient composition, phenolic content and free radical scavenging activity of some uncommon vegetables of Pakistan.

    PubMed

    Khattak, Khanzadi Fatima

    2011-07-01

    Vegetables play a vital role in the prevention of human disease and in the improvement of general health as these contain vitamins, amino acids, fiber, antioxidants and minerals. In the present study, some less familiar vegetables of Pakistan namely chickpea (leaves), chungah (shoots), drumstick tree (inflorescences), radish (fruit pods), mountain ebony (flower buds), mustard (leaves), purslane (leaves) and white goosefoot (leaves and shoots) were evaluated for proximate composition, mineral content, phenolic content and free radical scavenging activity. The protein, fat, fiber, carbohydrate and ash contents of the selected vegetables were in the range of 2.9 to 6.6%, 0.2 to 2.5%, 2.4 to 8.6%, 9.7 to 20.1% and 1.0 to 2.3%, respectively. The concentration of vitamin C ranged between 32.6 to 120.1 mg/100 g. The phosphorus, calcium, iron, zinc, manganese, magnesium and copper were 190 to 3400, 103 to 987, 19 to 93, 12 to 47, 9 to 121, 299 to 1635 and non detectable level to 42 mg/kg, respectively. The amount of total phenolic content varied from 55.3 to 221.0 mg/g in the dry methanolic extracts of the studied plants. The EC(50) values were below 1400 μg/ml, indicating that all the studied vegetables have good scavenging effect on DPPH radical. PMID:21715260

  1. Indoline Amide Glucosides from Portulaca oleracea: Isolation, Structure, and DPPH Radical Scavenging Activity.

    PubMed

    Jiao, Ze-Zhao; Yue, Su; Sun, Hong-Xiang; Jin, Tian-Yun; Wang, Hai-Na; Zhu, Rong-Xiu; Xiang, Lan

    2015-11-25

    A polyamide column chromatography method using an aqueous ammonia mobile phase was developed for large-scale accumulation of water-soluble indoline amide glucosides from a medicinal plant, Portulaca oleracea. Ten new [oleraceins H, I, K, L, N, O, P, Q, R, S (1-10)] and four known [oleraceins A-D (11-14)] indoline amide glucosides were further purified and structurally characterized by various chromatographic and spectroscopic methods. The DPPH radical scavenging activities of oleraceins K (5) and L (6), with EC50 values of 15.30 and 16.13 μM, respectively, were twice that of a natural antioxidant, vitamin C; the EC50 values of the 12 other indoline amides, which ranged from 29.05 to 43.52 μM, were similar to that of vitamin C. Structure-activity relationships indicated that the DPPH radical scavenging activities of these indoline amides correlate with the numbers and positions of the phenolic hydroxy groups. PMID:26562741

  2. The QSAR study of flavonoid-metal complexes scavenging rad OH free radical

    NASA Astrophysics Data System (ADS)

    Wang, Bo-chu; Qian, Jun-zhen; Fan, Ying; Tan, Jun

    2014-10-01

    Flavonoid-metal complexes have antioxidant activities. However, quantitative structure-activity relationships (QSAR) of flavonoid-metal complexes and their antioxidant activities has still not been tackled. On the basis of 21 structures of flavonoid-metal complexes and their antioxidant activities for scavenging rad OH free radical, we optimised their structures using Gaussian 03 software package and we subsequently calculated and chose 18 quantum chemistry descriptors such as dipole, charge and energy. Then we chose several quantum chemistry descriptors that are very important to the IC50 of flavonoid-metal complexes for scavenging rad OH free radical through method of stepwise linear regression, Meanwhile we obtained 4 new variables through the principal component analysis. Finally, we built the QSAR models based on those important quantum chemistry descriptors and the 4 new variables as the independent variables and the IC50 as the dependent variable using an Artificial Neural Network (ANN), and we validated the two models using experimental data. These results show that the two models in this paper are reliable and predictable.

  3. DPPH free radical scavenging activity and phenotypic difference in hepatoprotective plant (Silybum marianum L.).

    PubMed

    Ahmad, Nisar; Fazal, Hina; Abbasi, Bilal Haider; Anwar, Shazma; Basir, Abdul

    2013-06-01

    Silybum marianum L. is medicinally important for its active principle component silymarin. Silymarin regenerates damaged hepatic tissues. On the basis of such regenerative properties, the radical scavenging activity (1,1-diphenyl-2-picrylhydrazyl (DPPH)) of different tissues and the phenotypic difference of the hepatoprotective species, S. marianum L. were evaluated. There was less phenotypic difference in purple and white varieties of S. marianum. Assay of the antioxidant potential of different parts of the plant revealed that significantly higher activity (78.2%) was observed in seeds of the purple flowering plant than seeds of white flowering plant (49%) after different time intervals. Young leaves collected from white flowering plant exhibit 64.8% activity, which is higher than the purple flowering plant (55.1%). Significantly, same activity was observed in mature leaves of white (52%) and purple flowering plants (50%). The main stem collected from both the varieties exhibits similar activity from 50 to 52%. A 67.2% activity was recorded for mature roots of white flowering plant followed by roots of the purple variety (65%). The present study revealed that seeds and roots of both the varieties scavenge and detoxify more DPPH free radicals than other plant parts and can be used as a source of natural antioxidants and food additives. PMID:22362017

  4. Changes in structural characteristics of antioxidative soy protein hydrolysates resulting from scavenging of hydroxyl radicals.

    PubMed

    Zhao, Jing; Xiong, Youling L; McNear, Dave H

    2013-02-01

    Antioxidant activity of soy protein (SP) and its hydrolyzed peptides has been widely reported. During scavenging of radicals, these antioxidative compounds would be oxidatively modified, but their fate is not understood. The objective of this study was to evaluate the structural characteristics of SP hydrolysates (SPHs), compared to intact SP, when used to neutralize hydroxyl radicals (•OH). SPHs with degree of hydrolysis (DH) 1 to 5 were prepared with Alcalase. Antioxidant activity of SPHs was confirmed by lipid oxidation inhibition measured with thiobarbituric acid-reactive substances, ability to scavenge 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radicals, and ferrous ion chelation capability. Oxidation of SPHs was initiated by reaction with •OH generated from 0.1 mM FeCl(3) , 20 mM H(2) O(2) , and 1.0 mM ascorbate. After oxidative stress, carbonyl content of SPHs increased by 2- to 3-fold and sulfhydryl groups decreased by up to 42% compared to nonoxidized samples (P < 0.05). Methionine, histidine, and lysine residues were significantly reduced as a result of inactivating •OH (P < 0.05). Attenuated total reflectance-Fourier transform infrared and circular dichroism spectroscopy suggested the conversion of helical structure to strands and turns. Oxidatively modified SPHs had a lower intrinsic fluorescence intensity but similar solubility when compared to nonoxidized samples. These structural changes due to •OH stress may impact the ingredient interaction and functionality of SPHs in food products. PMID:23331209

  5. Targeted acylation for all the hydroxyls of (+)-catechin and evaluation of their individual contribution to radical scavenging activity.

    PubMed

    Hong, Shan; Liu, Songbai

    2016-04-15

    The reactivity profile of all the hydroxyl groups in (+)-catechin towards acylation and their respective contribution to radical scavenging activity were systematically explored in this work. Selective acylation of the hydroxyls on different rings was carried out employing either a basic or acidic activation strategy. Monoacylation of B ring was achieved effectively with the aid of dimethyltin dichloride. Monoacylation of A ring was accomplished by sequential protection and deprotection of B and C rings. Based on specific acylation of all the individual hydroxyls of (+)-catechins, the structure radical scavenging activity relationship of each hydroxyl of (+)-catechin was established. It was demonstrated that the vicinal phenolic hydroxyls on B ring played the most important role in the ABTS radical scavenging activity and those on A and C rings made a much smaller contribution. This study has laid solid groundwork for further modification of the catechins and improvement of their properties. PMID:26616969

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

    PubMed

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

    2015-01-01

    Changes in chemical constituent contents and DPPH radical-scavenging activity in fruits of pear (Pyrus pyrifolia) cultivars during the development were investigated. The fruits of seven cultivars (cv. Niitaka, Chuhwangbae, Wonhwang, Hwangkeumbae, Hwasan, Manpungbae, and Imamuraaki) were collected at 15-day intervals after day 20 of florescence. Vitamins (ascorbic acid and α-tocopherol), arbutin, chlorogenic acid, malaxinic acid, total caffeic acid, total flavonoids, and total phenolics were the highest in immature pear fruit on day 20 after florescence among samples at different growth stages. All of these compounds decreased gradually in the fruit during the development. Immature pear fruit on day 35 or 50 after florescence exhibited higher free radical-scavenging activity than that at other times, although activities were slightly different among cultivars. The chemical constituent contents and free radical-scavenging activity were largely different among immature fruits of the pear cultivars, but small differences were observed when they matured. PMID:25348501

  7. On the antioxidant properties of kynurenic acid: free radical scavenging activity and inhibition of oxidative stress.

    PubMed

    Lugo-Huitrón, R; Blanco-Ayala, T; Ugalde-Muñiz, P; Carrillo-Mora, P; Pedraza-Chaverrí, J; Silva-Adaya, D; Maldonado, P D; Torres, I; Pinzón, E; Ortiz-Islas, E; López, T; García, E; Pineda, B; Torres-Ramos, M; Santamaría, A; La Cruz, V Pérez-De

    2011-01-01

    Kynurenic acid (KYNA) is an endogenous metabolite of the kynurenine pathway for tryptophan degradation and an antagonist of both N-methyl-D-aspartate (NMDA) and alpha-7 nicotinic acetylcholine (α7nACh) receptors. KYNA has also been shown to scavenge hydroxyl radicals (OH) under controlled conditions of free radical production. In this work we evaluated the ability of KYNA to scavenge superoxide anion (O(2)(-)) and peroxynitrite (ONOO(-)). The scavenging ability of KYNA (expressed as IC(50) values) was as follows: OH=O(2)(-)>ONOO(-). In parallel, the antiperoxidative and scavenging capacities of KYNA (0-150 μM) were tested in cerebellum and forebrain homogenates exposed to 5 μM FeSO(4) and 2.5 mM 3-nitropropionic acid (3-NPA). Both FeSO(4) and 3-NPA increased lipid peroxidation (LP) and ROS formation in a significant manner in these preparations, whereas KYNA significantly reduced these markers. Reactive oxygen species (ROS) formation were determined in the presence of FeSO(4) and/or KYNA (0-100 μM), both at intra and extracellular levels. An increase in ROS formation was induced by FeSO(4) in forebrain and cerebellum in a time-dependent manner, and KYNA reduced this effect in a concentration-dependent manner. To further know whether the effect of KYNA on oxidative stress is independent of NMDA and nicotinic receptors, we also tested KYNA (0-100 μM) in a biological preparation free of these receptors - defolliculated Xenopus laevis oocytes - incubated with FeSO(4) for 1 h. A 3-fold increase in LP and a 2-fold increase in ROS formation were seen after exposure to FeSO(4), whereas KYNA attenuated these effects in a concentration-dependent manner. In addition, the in vivo formation of OH evoked by an acute infusion of FeSO(4) (100 μM) in the rat striatum was estimated by microdialysis and challenged by a topic infusion of KYNA (1 μM). FeSO(4) increased the striatal OH production, while KYNA mitigated this effect. Altogether, these data strongly suggest that KYNA

  8. Antioxidant potential and radical scavenging effects of various extracts from Abutilon indicum and Abutilon muticum.

    PubMed

    Yasmin, Sammia; Kashmiri, Muhammad Akram; Asghar, Muhammad Nadeem; Ahmad, Mushtaq; Mohy-ud-Din, Ayesha

    2010-03-01

    Abutilon indicum L. (Malvaceae) and Abutilon muticum DC. (Malvaceae) are traditional medicinal herbs used for analgesic, anthelmintic, hepatoprotective, and hypoglycemic properties. These effects may be correlated with the presence of antioxidant compounds. Extracts in organic solvents from the aerial parts and roots of both species were prepared and evaluated for their total antioxidant capacity (TAC), total phenolic content, and total flavonoid content. The Trolox equivalent antioxidant capacity (TEAC) of all the extracts of both plants was found, employing ABTS and FRAP assays. TEAC values ranged from 3.019 to 10.5 muM for n-hexane and butanol fractions of Abutilon indicum and from 2.247 to 14.208 muM for n-hexane and butanol fractions of Abutilon muticum, respectively, using the ABTS assay. The FRAP assay showed reducing powers of the fractions in the order of butanol > ethyl acetate > chloroform > n-hexane and butanol > chloroform > hexane > ethyl acetate for Abutilon indicum and Abutilon muticum, respectively. EC(50) and T(EC50) values for the extracts of both plants were determined using the DPPH free radical assay. The reaction kinetics with this free radical indicated the presence of both slow reacting and fast reacting antioxidant components in the extracts of both plants. The antioxidant/radical scavenging capacity of the extracts was found to be a dose-dependent activity. The results obtained in the present study indicate that both Abutilon species are potential sources of natural antioxidants. PMID:20645814

  9. Mitigation of 3-Monochloro-1,2-propanediol Ester Formation by Radical Scavengers.

    PubMed

    Zhang, Hai; Jin, Pengwei; Zhang, Min; Cheong, Ling-Zhi; Hu, Peng; Zhao, Yue; Yu, Liangli; Wang, Yong; Jiang, Yuanrong; Xu, Xuebing

    2016-07-27

    The present study investigated the possible mechanism of free radical scavengers on mitigation of 3-monochloro-1,2-propanediol (3-MCPD) fatty acid ester formation in vegetable oils. The electron spin resonance investigation showed that the concentration of free radicals could be clearly decreased in 1,2-distearoyl-sn-glycerol (DSG) samples by all four antioxidants (l-ascorbyl palmitate, α-tocopherol, lipophilic tea polyphenols, and rosemary extract) at 120 °C for 20 min under a N2 atmosphere. Moreover, the rosemary extract exhibited the highest inhibition efficiency. The Fourier transform infrared spectroscopy examination of DSG with α-tocopherol at 25 and 120 °C revealed that α-tocopherol could prevent the involvement of an ester carbonyl group of DSG in forming the cyclic acyloxonium free radical intermediate. Furthermore, the ultraperformance liquid chromatography-quadrupole-time-of-flight mass spectrometry analysis showed that α-tocopherol could suppress the formation of 3-MCPD di- and monoesters. Finally, the four antioxidants could decrease 3-MCPD esters in the palm oil during deodorization. Particularly, the rosemary extract also showed the highest efficiency in 3-MCPD ester mitigation. PMID:27396990

  10. Inhibition of adriamycin cardiotoxicity by 5-fluorouracil: a potential free oxygen radical scavenger.

    PubMed

    Stathopoulos, G P; Malamos, N A; Dontas, I; Deliconstantinos, G; Perrea-Kotsareli, D; Karayannacos, P E

    1998-01-01

    Adriamycin (ADR), a broad spectrum anticancer agent, has a limit to total dose used, due to cumulative cardiotoxicity. This side effect has been tested in the present study in combined administration with 5-fluorouracil a cytotoxic drug that often is applied together with ADR in cancer treatment. The study was performed on Wistar rats, and the experiment consisted of weekly administration for 12 weeks of adriamycin alone, of 5-fluorouracil alone, a combination of both, and a control group (normal saline) in separate groups comprising 42 animals each. The histology of the cardiac muscle, large vessels and liver, biochemistry of serum cholesterol, triglycerides and HDL-C and oxygen free radical production were examined. It was found that addition of 5-FU to the ADR administration reduced significantly the cardiac lesions, delayed and reduced the increase of serum lipids, produced by ADR alone and oxygen free radical production was also reduced, indicating that 5-fluorouracil is acting as a scavenger of free radicals. PMID:9891497

  11. Variable protection by OH scavengers against radiation-induced inactivation of isolated transcriptionally active chromatin: the influence of secondary radicals

    SciTech Connect

    Herskind, C.; Westergaard, O.

    1988-04-01

    Isolated r-chromatin, the chromatin form of the extrachromosomal gene coding for the rRNA precursor in Tetrahymena, has been used to study radiation-induced inactivation in vitro in the presence of the OH radical scavengers, t-butanol, formate ions, and methanol. Induction of biologically important DNA lesions was detected by the effect on transcription by endogenous RNA polymerases associated with the isolated r-chromatin. The OH scavengers were found to give strong protection in the presence of oxygen as anticipated from previous results obtained with this system. By contrast, only a modest protection was observed under 100% N/sub 2/ or 100% N/sub 2/O, and the level of protection was different for each scavenger. The data suggest that secondary radicals may inactivate r-chromatin under anoxia. In the presence of oxygen, the secondary radicals react with O/sub 2/ to form organic peroxy radicals (or O/sub 2/-) which seem to be less reactive. Since the protective effect of the OH scavengers varies with the gassing conditions, the dose modifying effects of O/sub 2/ and N/sub 2/O relative to N/sub 2/ depend on the identity and concentration of OH scavenger. The implications for radiation-chemical studies on DNA and living cells are discussed.

  12. Towards fuel cell membranes with improved lifetime: Aquivion® Perfluorosulfonic Acid membranes containing immobilized radical scavengers

    NASA Astrophysics Data System (ADS)

    D'Urso, C.; Oldani, C.; Baglio, V.; Merlo, L.; Aricò, A. S.

    2014-12-01

    A facile synthesis, based on a wet impregnation technique and a thermal treatment, of a novel silica-supported cerium-oxide-based radical scavenger bearing sulfonic acid functionalities is presented. This material is loaded as a filler in ePTFE reinforced membranes (called R79-02S) prepared starting from Aquivion® Perfluoro-Sulfonic Acid (PFSA) dispersions. The aim is to mitigate the peroxy radicals attack to the polymeric membrane under fuel cell operating conditions. These membranes show much longer (7 times more) life-time in Accelerated Stress Tests (AST) and reduced fluoride release (about one half) in Fenton's tests than the radical scavenger-free membrane without any loss in electrochemical performance. Scavenger-free Aquivion® PFSA-based membrane durability is about 200 h in AST whereas the same membrane containing the newly developed radical scavenger exceeds 1400 h. These results confirm the stability of the modified membranes and the excellent activity of the composite scavenger in mitigating the polymer electrolyte degradation.

  13. Interactions between carnosine and captopril on free radical scavenging activity and angiotensin-converting enzyme activity in vitro.

    PubMed

    Nakagawa, Kazuo; Ueno, Akemi; Nishikawa, Yukari

    2006-01-01

    Interactions between carnosine (beta-alanyl-L-histidine), being plentiful in skeletal muscles and neuronal tissues, and captopril, a widely used angiotensin-converting enzyme (ACE) inhibitor, were examined concerning free radical scavenging activity and ACE activity in vitro. Not only captopril, but also carnosine, at concentrations less than those ordinarily found in muscles and neuronal tissues, significantly scavenged 2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonate) (ABTS) radical cations, and inhibited ACE activity. Cupric ions reversed the ABTS scavenging activity of carnosine and captopril, whereas cupric ions strengthened the inhibitory action of carnosine on ACE activity. In contrast, cupric ions antagonized the inhibition of ACE activity induced by ethylenediaminetetraacetic acid, indicating that the inhibitory effect of carnosine on ACE activity is not related to the chelating action of carnosine. On the other hand, carnosine and captopril synergistically enhanced the free radical scavenging activity, but not the inhibitory effect on the ACE activity. These data suggest that carnosine in its concurrent use with captopril could act as a beneficial free radical scavenger, with less danger of overdose, in the inhibition of ACE activity. PMID:16394648

  14. Troxerutin, a plant flavonoid, protects cells against oxidative stress-induced cell death through radical scavenging mechanism.

    PubMed

    Panat, Niranjan A; Maurya, Dharmendra K; Ghaskadbi, Saroj S; Sandur, Santosh K

    2016-03-01

    Troxerutin (TRX) is a flavonoid present in tea, coffee, cereal grains, various fruits and vegetables have been reported to exhibit radioprotective, antithrombotic, nephro and hepato-protective effects. A systematic study was undertaken to evaluate its free radical scavenging ability and anti-apoptotic activity in cell-free and cellular systems. TRX scavenged superoxide, nitric oxide and also other model stable radicals like 1,1-diphenyl-2-picryl-hydazyl, and 2,2'-azinobis3-ethylbenzothiazoline-6-sulfonic acid. It reacted with hydroxyl radicals, carbonate and thiocyanate anions, as evaluated by pulse radiolysis and stopped flow techniques. TRX protected different cell types (epithelial cells, fibroblasts and lymphocytes) against peroxyl radical-induced apoptosis, necrosis and mitotic death. It scavenged intracellular basal and inducible ROS levels and also restored depletion of intracellular GSH levels, suggesting that free radical scavenging ability may be responsible for the observed cytoprotection of different cell types. TRX may find application as an adjuvant in treating various diseases attributed to oxidative stress. PMID:26471524

  15. Free radical scavenging activity, total phenolic content, total antioxidant status, and total oxidant status of endemic Thermopsis turcica

    PubMed Central

    Aksoy, Laçine; Kolay, Erdi; Ağılönü, Yasin; Aslan, Zeyneb; Kargıoğlu, Mustafa

    2013-01-01

    Thermopsis turcica, endemic to Turkey, is in danger of extinction. Studies on this species are very few due to the fact that it was only discovered in 1983 and grows in a small circumscribed area in Turkey. In this study, free radical scavenging activity, total phenolic content, total oxidant status (TOS), and total antioxidant status (TAS) of methanol (TTM) and acetone (TTA) extracts of T. turcica were measured spectroscopically. Free radical scavenging activity was determined according to the elimination of DPPH radicals and total phenol content was determined by the Folin–Ciocalteu reaction. Total oxidant status (TOS) and total antioxidant status (TAS) were measured with commercially available kits. Methanol and acetone extracts of T. turcica were found to have a specific radical scavenging effect. This effect was found to be related to the total phenolic content of the extracts. Since the TTA had a higher phenolic content than the methanol extract, it had a stronger radical scavenging effect. In addition, the total antioxidant capacity of the methanol extract was observed to be higher than that of its acetone counterpart. As a result, due to its antioxidative properties, T. turcica is thought to be a natural source of antioxidants. PMID:23961240

  16. STUDY TO ESTABLISH THE ACCEPTANCE RANGE FOR PEROXYL RADICALS SCAVENGER CAPACITY OF NATURAL SOD.

    PubMed

    Lupu, Andreea-Roxana; Cremer, Lidia

    2015-01-01

    In the context of an emerging market of food supplements, the proven quality of the antioxidant products should be the main criteria for using them. The production process has to be carefully controlled and complementary tests are needed to demonstrate the correspondence between real and declared properties of final product. Using well characterized compounds with proven antioxidant activity in biological systems as reference brings a plus of rigorously to the testing protocol. The aim of this study was to determine the acceptance range for the antioxidant (peroxyl radicals scavenger) capacity of "Natural SOD" by using for comparison ascorbic acid (vitamin C). The established acceptance range complete our previous results concerning the antioxidant capacity of Natural SOD using validated ORAC method and creates premises for supplementary checking of the batches in the current production and improving the product quality. PMID:27328523

  17. Phenylpropanoid Glycoside Analogues: Enzymatic Synthesis, Antioxidant Activity and Theoretical Study of Their Free Radical Scavenger Mechanism

    PubMed Central

    López-Munguía, Agustín; Hernández-Romero, Yanet; Pedraza-Chaverri, José; Miranda-Molina, Alfonso; Regla, Ignacio; Martínez, Ana; Castillo, Edmundo

    2011-01-01

    Phenylpropanoid glycosides (PPGs) are natural compounds present in several medicinal plants that have high antioxidant power and diverse biological activities. Because of their low content in plants (less than 5% w/w), several chemical synthetic routes to produce PPGs have been developed, but their synthesis is a time consuming process and the achieved yields are often low. In this study, an alternative and efficient two-step biosynthetic route to obtain natural PPG analogues is reported for the first time. Two galactosides were initially synthesized from vanillyl alcohol and homovanillyl alcohol by a transgalactosylation reaction catalyzed by Kluyveromyces lactis β-galactosidase in saturated lactose solutions with a 30%–35% yield. To synthesize PPGs, the galactoconjugates were esterified with saturated and unsaturated hydroxycinnamic acid derivatives using Candida antarctica Lipase B (CaL-B) as a biocatalyst with 40%–60% yields. The scavenging ability of the phenolic raw materials, intermediates and PPGs was evaluated by the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) method. It was found that the biosynthesized PPGs had higher scavenging abilities when compared to ascorbic acid, the reference compound, while their antioxidant activities were found similar to that of natural PPGs. Moreover, density functional theory (DFT) calculations were used to determine that the PPGs antioxidant mechanism proceeds through a sequential proton loss single electron transfer (SPLET). The enzymatic process reported in this study is an efficient and versatile route to obtain PPGs from different phenylpropanoid acids, sugars and phenolic alcohols. PMID:21674039

  18. Free radical scavenging, antidiarrheal and anthelmintic activity of Pistia stratiotes L. extracts and its phytochemical analysis.

    PubMed

    Bin Karim, Mohammed Faisal; Imam, Hasan; Sarker, Md Moklesur-Rahman; Uddin, Nizam; Hasan, Nahid; Paul, Nirmala; Haque, Tahmina

    2015-05-01

    In this phyto-pharmacological screening of Pistia stratiotes L leaf and root extracts each separately in two different solvents demonstrated its potential medicinal value. Apparent antioxidant value is demonstrated by DPPH, Nitric oxide scavenging and Ferric ion reducing method. Additionally, total flavonoid and phenolic compounds were measured. The leaf methanolic extract scavenged both nitric oxide (NO) and DPPH radical with a dose dependent manner. But the pet ether fraction of root was found to have highest efficacy in Fe(3±) reducing power assay. Flavonoid was found to contain highest in the pet ether fraction of root (411.35mg/g) in terms of quercetin equivalent, similarly highest amount (34.96mg/g) of total phenolic compounds (assayed as gallic acid equivalents) were found to contain in the same fraction. The methanolic fractions appeared less cytotoxic compared to pet ether extracts. The plant extracts caused a dose dependent decrease in faecal droppings in both castor oil and magnesium sulphate induced diarrhea, where as leaf extracts in each solvent appeared most effective. Also, the plant extracts showed anthelmintic activity in earthworm by inducing paralysis and death in a dose dependent manner. At highest doses (50 mg/ml) all fractions were almost effective as the positive control piperazine citrate (10 mg/ml). Thus, besides this cytotoxic effect it's traditional claim for therapeutic use can never be overlooked. PMID:26004725

  19. Antioxidant and free radical scavenging activities of some medicinal plants from the Lamiaceae.

    PubMed

    Matkowski, Adam; Piotrowska, Magdalena

    2006-07-01

    Antioxidative effects of methanolic extracts from six wild European Lamiaceae species have been studied with the use of three in vitro assays. The ability of scavenging free radicals was measured by DPPH reduction spectrophotometric assay. The reducing potential towards transition metals was tested by phosphomolybdenum method and the inhibition of lipid oxidation was tested by Fe/ascorbate system with photometric TBARS detection. All studied herbs exposed strong antioxidant capability, but the results were different for each species depending on the applied test. In DPPH scavenging the order from strongest to the weakest was: Leonurus cardiaca, Lamium album, Marrubium vulgare, Stachys officinalis, Lamium purpureum, Galeopsis speciosa. With phosphomolybdenum method the extract of S. officinalis was the strongest in both 40 degrees Celsius and 90 degrees Celsius but other species acted differently in both temperatures. In lipid peroxidation assay, the maximum inhibition of 78% was reached by S. officinalis and M. vulgare, whereas for both Lamium sp. and L. cardiaca slightly exceeded 70% and for G. speciosa reached 65%. The observed differences indicate the complexity of involved mechanisms and support the necessity of combining several assays in studying the antioxidant potential of medicinal plants. PMID:16713687

  20. Fingerprints, Pharmaceutical and Radical Scavenging Activity Evaluation of an Alzheimer-Targeted Herbal Preparation

    PubMed Central

    Dabaghian, Farid; Khademian, Sedigheh; Azadi, Amir; Zarshenas, Mohammad

    2016-01-01

    Background: As the most common form of dementia, Alzheimer disease is characterized by progressive loss of memory and deterioration of cognitive functions. It is predicted that about 75.63 million people would suffer from dementia by 2030. Apart from conventional remedies, the application of herbal medicines is on the rise. There are numerous natural medicaments reported in the traditional manuscript of Persian medicine. Accordingly, in the present study, the intended remedy was selected and an appropriate pharmacognostical and pharmaceutical evaluations were performed. Methods: By searching through the traditional pharmaceutical manuscripts such as Qarabadeen-e-Salehi, Qarabadeen-e-Azam, Qarabadeen-e-Ghaderi and Canon of Medicine, a simple but proven compound remedy (frankincense and black pepper) was selected. A floating tablet was designed and formulated from those herbal components. Related pharmaceutical assessments such as weight variation, hardness, friability, and disintegration tests as well as pharmacognostical evaluations such as microscopic characterization, TLC, GC/MS, FT/IR fingerprints, and radical scavenging activity assessment (DPPH) were performed. Results: The resulting formulation, as a floating tablet, included 60% of frankincense gum and 15% of black pepper along with appropriate pharmaceutical ingredients (weight variation: 0.219±0.004 g, hardness: 6.50±0.67, friability: 0.45%, disintegration time >30 min). Microscopic characterization demonstrated stone cells, calcium oxalate crystals, sclereids of endocarp and pitted cells of mesocarp of pepper fruits as well as oil drops of frankincense gum. TLC fingerprinting showed classes of secondary metabolites related to both components. GC/MS analysis revealed Acetyl acetate and trans-Caryophyllene as the main constituent. Moderate radical scavenging activity (IC50 >100 µg/ml) was calculated for the methanol extract of tablets. Conclusion: Carrying out and validating a GC method for

  1. In vitro free radical scavenging and antioxidant properties of ethanol extract of Terminalia glaucescens

    PubMed Central

    Olugbami, J. Olorunjuwon; Gbadegesin, Michael A.; Odunola, Oyeronke A.

    2015-01-01

    Background: Reactive oxygen species (ROS) are implicated in various pathological conditions. Synthetic antioxidants have adverse health effects, while many medicinal plants have antioxidant components that can prevent the harmful effects of ROS. Objectives: This study quantitatively determined the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant properties of ethanol extract of the stem bark of Terminalia glaucescens (EESTG). Materials and Methods: The objectives were achieved based on in vitro assays. Data were analyzed by Sigma Plot (version 11.0). Results: Using gallic acid as the standard compound, TPC value obtained was 596.57 μg GAE/mg extract. TFC content of EESTG, determined as quercetin equivalent was 129.58 μg QE/mg extract. Furthermore, EESTG significantly (P < 0.001) displayed higher reducing power activity than the standard compounds (ascorbic acid and butylated hydroxytoluene [BHT]). Total antioxidant capacity assay, measured by phosphomolybdate method, was 358.33 ± 5.77 μg butylated hydroxytoluene equivalents [BHTE]/mg extract. β-carotene-linoleate bleaching method affirmed the potency of EESTG because of its significantly (P < 0.001) higher anti-oxidant activity when compared with quercetin and BHT. Based on DPPH assay, EESTG displayed significantly (P < 0.001) higher activity than BHT, while the hydroxyl radical scavenging activities of BHT and quercetin significantly (P < 0.001) exceeded that of the extract, although EESTG still displayed a high level of activity obtained as 83.77% in comparison to 92.80% of the standard compounds. Conclusion: Findings from this study indicate the presence of promisingly potent phytoconstituents in EESTG that have the capability to act as antioxidants and free radical scavengers. PMID:25598635

  2. Application of UV-Vis spectrophotometric process for the assessment of indoloacridines as free radical scavenger.

    PubMed

    Sridharan, Makuteswaran; Prasad, K J Rajendra; Madhumitha, G; Al-Dhabi, Naif Abdullah; Arasu, Mariadhas Valan

    2016-09-01

    A conventional approach has been used to synthesis Indole fused acridine, 4a-e. In this paper to achieve the target molecule, 4 the reaction was performed via two steps. In step 1, there was a reaction between Carbazolone, 1 and benzophenone, 2 to get dihydroindoloacridine, 3. In step 2, compound, 3 was treated with 5% Palladium/Carbon in the presence of diphenyl ether for 5h to give a dark brown product, 4. The column chromatography was used to purify final product, 4. All the synthesized compounds such as 3 and 4 were characterized by melting point, FTIR, (1)H NMR, and Mass spectra. Further to check the purity of the compounds it was subjected to CHN analyzer. The target molecules such as 3 and 4 were screened for antimicrobial studies against bacteria such as Bacillus subtilis (B. subtilis), Staphylococcus aureus (S. aureus), Klebsiella pneumonia (K. pneumonia), Salmonella typhi (S. typhi); and fungi like Aspergillus niger (A. niger), Aspergillus fumigatus (A. fumigatus). The obtained results clearly proves that the target molecules shown reasonable activity against K. pneumonia and A. niger. Further the compounds were screened for free radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH). The free radical scavenging property was performed using UV-Visible spectroscopy. The results were compared with the standard BHT (Butylated Hydroxy Toluene). Compounds, 4a and 4e were shown higher percentage of inhibition when compare to the standard. The result confirms that further research on indoloacridine will leads effective drug to the market. PMID:27491030

  3. Crocin and geniposide profiles and radical scavenging activity of gardenia fruits (Gardenia jasminoides Ellis) from different cultivars and at the various stages of maturation.

    PubMed

    Chen, Yang; Zhang, Hao; Li, Yi-Xin; Cai, Le; Huang, Juan; Zhao, Can; Jia, Lin; Buchanan, Ryan; Yang, Ting; Jiang, Li-Juan

    2010-06-01

    The major components of gardenia fruits are geniposide and water soluble pigment crocins. In this study, we investigate crocins and geniposide profiles of gardenia fruits from different cultivars and at the various stages of maturation. DPPH scavenging activity of gardenia fruits from different cultivars and at the various stages of fruit maturation was also assayed. Quantitative determination of crocins in the gardenia at the various stages of maturation revealed a significant increase when ripening. However, geniposide content was negatively correlated with ripening stages. A significant difference was observed when comparing crocin content of different gardenia from various cultivars and geniposide content also showed marked variety. Current study indicated no relationship between crocin and geniposide content in gardenia fruits at the various stages of maturation and DPPH radical scavenging activity. Data showed that, although crocins feature markedly less DPPH scavenging activity than gardenia ethanol extract, total crocin content of gardenias collected in various cultivars correlate, to a certain degree, with radical scavenging effects of the Chinese traditional medicine (r=0.75). PMID:19815056

  4. In vitro free radical scavenging and DNA damage protective property of Coriandrum sativum L. leaves extract.

    PubMed

    Harsha, S N; Anilakumar, K R

    2014-08-01

    Coriandrum sativum L. (coriander), an everyday spice in the Indian kitchen is known to add flavor to the cuisine. It is an annual herb belonging to the Apiaceae (Umbellifera) family. The hydro-alcohol extract of Coriandrum sativum L. at the dose of 1 mg/ml was subjected to a series of in vitro assays viz. 2, 2'- diphenyl-1-picrylhydrazyl, lipid peroxidation by thiobarbituric acid, reducing power and nitric oxide (NO) radical scavenging in order to study its antioxidant efficacy in detail. The amount of flavonoids in 70% ethanol extract was found to be 44.5 μg and that of the total phenols was 133.74 μg gallic acid equivalents per mg extract. The extracts of the leaves showed metal chelating power, with IC50 values, 368.12 μg/ml where as that of standard EDTA was 26.7 μg/ml. The IC50 values for 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid radical scavenging was 222 μg/ml where as that of standard ascorbic acid was 22.6 μg/ml. The NO scavenging activity of the extract of the leaves showed IC50 value of 815.6 μg/ml; at the same time the standard BHA had 49.1 μg/ml. All the plant extracts provided DNA damage protection; however, the protection provided at the dose of 8 μg/ml was comparable to that of standard gallic acid. The Coriandrum sativum leaf extract was able to prevent in vitro lipid peroxidation with IC50 values; 589.6 μg/ml where as that of standard BHA was 16.3 μg/ml. Our results also showed significant ferric reducing power indicating the hydrogen donating ability of the extract. This study indicated the potential of the leaf extract as a source of natural antioxidants or nutraceuticals that could be of use in food industry with potential application to reduce oxidative stress in living system. PMID:25114344

  5. Radical scavenging ability of gallic acid toward OH and OOH radicals. Reaction mechanism and rate constants from the density functional theory.

    PubMed

    Marino, Tiziana; Galano, Annia; Russo, Nino

    2014-09-01

    Gallic acid is a ubiquitous compound, widely distributed in the vegetal kingdom and frequently found in the human diet. In the present work, its primary antioxidant activity has been investigated using the density functional theory (DFT), and the quantum mechanics-based test for overall free radical scavenging activity (QM-ORSA) protocol. It was found that gallic acid is a better antioxidant than the reference compound, Trolox, regardless of the polarity of the environment. In addition, gallic acid is predicted to be among the best peroxyl radical scavengers identified so far in nonpolar (lipid) media. This compound is capable of scavenging hydroxyl radicals at diffusion-limited rates, and hydroperoxyl radicals with rate constants in the order of 10(5) M(-1) s(-1). The deprotonation of gallic acid, in aqueous solution, is predicted to increase the protective action of this compound against oxidative stress. Gallic acid was also identified as a versatile scavenger, capable of rapidly deactivating a wide variety of reactive oxygen species (ROS) and reactive nitrogen species (RNS) via electron transfer at physiological pH. PMID:25119432

  6. Screening of free radical scavenging compounds in water extracts of Mentha samples using a postcolumn derivatization method.

    PubMed

    Koşar, Müberra; Dorman, H J Damien; Can Başer, K Hüsnü; Hiltunen, Raimo

    2004-08-11

    An on-line high-performance liquid chromatography-1,1-diphenyl-2-picrylhydrazyl (HPLC-DPPH*) method has been improved for the detection of polar and nonpolar radical scavenging compounds in complex plant extracts. Nine water extracts were prepared from different Mentha species, varieties, hybrids, and cultivars. After the components within each extract had been separated by reverse phase chromatography using 10-100% methanol with 2% acetic acid as a mobile phase, analytes within the eluent capable of scavenging a citric acid-sodium citrate-buffered methanol 1,1-diphenyl-2-picrylhydrazyl solution were detected by postcolumn derivatization at 517 nm. The HPLC-DPPH* on-line method was applied to the qualitative and quantitative analysis of Mentha extracts. There was a strong correlation between the scavenging (negative) peak area and the concentration of the radical scavenging reference substances used. The minimum detectable concentration (microg/mL) of the antioxidant compounds was determined. Caffeic acid, eriocitrin (eriodictyol-7-O-rutinoside), luteolin-7-O-glucoside, and rosmarinic acid were identified as the dominant radical scavengers in these extracts by this method. PMID:15291467

  7. Anti-genotoxic and free-radical scavenging activities of extracts from (Tunisian) Myrtus communis.

    PubMed

    Hayder, N; Abdelwahed, A; Kilani, S; Ammar, R Ben; Mahmoud, A; Ghedira, K; Chekir-Ghedira, L

    2004-11-14

    The effect of extracts from leaves of Myrtus communis on the SOS reponse induced by Aflatoxin B1 (AFB1) and Nifuroxazide was investigated in a bacterial assay system, i.e. the SOS chromotest with Escherichia coli PQ37. Aqueous extract, the total flavonoids oligomer fraction (TOF), hexane, chloroform, ethyl acetate and methanol extracts and essential oil obtained from M. communis significantly decreased the SOS response induced by AFB1 (10 microg/assay) and Nifuroxazide (20 microg/assay). Ethyl acetate and methanol extracts showed the strongest inhibition of the induction of the SOS response by the indirectly genotoxic AFB1. The methanol and aqueous extracts exhibited the highest level of protection towards the SOS-induced response by the directly genotoxic Nifuroxazide. In addition to anti-genotoxic activity, the aqueous extract, the TOF, and the ethyl acetate and methanol extracts showed an important free-radical scavenging activity towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. These results suggest the future utilization of these extracts as additives in chemoprevention studies. PMID:15474415

  8. Radical Scavenging Activities of Tannin Extracted from Amaranth (Amaranthus caudatus L.).

    PubMed

    Jo, Hyeon-Ju; Chung, Kang-Hyun; Yoon, Jin A; Lee, Kwon-Jai; Song, Byeong Chun; An, Jeung Hee

    2015-06-01

    This study investigates the bioactivity of tannin from amaranth (Amaranthus caudatus L.) extracts. The antioxidant activities of the extracts from amaranth leaves, flowers, and seeds were evaluated. Tannin from leaves of amaranth has been evaluated for superoxide scavenging activity by using DPPH and ABTS(+) analysis, reducing power, protective effect against H2O2-induced oxidative damage in L-132 and BNL-CL2 cells, and inhibition of superoxide radical effects on HL-60 cells. At a concentration of 100 μg/ml, tannin showed protective effects and restored cell survival to 69.2% and 41.8% for L-132 and BNL-CL2 cells, respectively. Furthermore, at the same concentration, tannin inhibited 41% of the activity of the superoxide radical on HL-60 cells and 43.4% of the increase in nitric oxide levels in RAW 264.7 cells. The expression levels of the antioxidant-associated protein SOD-1 were significantly increased in a concentration-dependent manner in RAW 264.7 cells treated with tannin from amaranth leaves. These results suggest that tannin from the leaves of Amaranthus caudatus L. is a promising source of antioxidant component that can be used as a food preservative or nutraceutical. PMID:25639718

  9. Determination of DPPH free radical scavenging activity: application of artificial neural networks.

    PubMed

    Musa, Khalid Hamid; Abdullah, Aminah; Al-Haiqi, Ahmed

    2016-03-01

    A new computational approach for the determination of 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity (DPPH-RSA) in food is reported, based on the concept of machine learning. Trolox standard was mix with DPPH at different concentrations to produce different colors from purple to yellow. Artificial neural network (ANN) was trained on a typical set of images of the DPPH radical reacting with different levels of Trolox. This allowed the neural network to classify future images of any sample into the correct class of RSA level. The ANN was then able to determine the DPPH-RSA of cinnamon, clove, mung bean, red bean, red rice, brown rice, black rice and tea extract and the results were compared with data obtained using a spectrophotometer. The application of ANN correlated well to the spectrophotometric classical procedure and thus do not require the use of spectrophotometer, and it could be used to obtain semi-quantitative results of DPPH-RSA. PMID:26471610

  10. In Vitro Antimicrobial Bioassays, DPPH Radical Scavenging Activity, and FTIR Spectroscopy Analysis of Heliotropium bacciferum.

    PubMed

    Ahmad, Sohail; AbdEl-Salam, Naser M; Ullah, Riaz

    2016-01-01

    The present study deals with the antimicrobial, antioxidant, and functional group analysis of Heliotropium bacciferum extracts. Disc diffusion susceptibility method was followed for antimicrobial assessment. Noteworthy antimicrobial activities were recorded by various plant extracts against antibiotic resistant microorganisms. Plant flower extracts antioxidant activity was investigated against 2, 2-diphenyl-1-picryl hydrazyl radical by ultraviolet spectrophotometer (517 nm). Plant extracts displayed noteworthy radical scavenging activities at all concentrations (25-225 μg/mL). Notable activities were recorded by crude, chloroform and ethyl acetate extracts up to 88.27% at 225 μg/mL concentration. Compounds functional groups were examined by Fourier transform infrared spectroscopic studies. Alkanes, alkenes, alkyl halides, amines, carboxylic acids, amides, esters, alcohols, phenols, nitrocompounds, and aromatic compounds were identified by FTIR analysis. Thin layer chromatography bioautography was carried out for all plant extracts. Different bands were separated by various solvent systems. The results of the current study justify the use of Heliotropium bacciferum in traditional remedial herbal medicines. PMID:27597961

  11. In Vitro Antimicrobial Bioassays, DPPH Radical Scavenging Activity, and FTIR Spectroscopy Analysis of Heliotropium bacciferum

    PubMed Central

    2016-01-01

    The present study deals with the antimicrobial, antioxidant, and functional group analysis of Heliotropium bacciferum extracts. Disc diffusion susceptibility method was followed for antimicrobial assessment. Noteworthy antimicrobial activities were recorded by various plant extracts against antibiotic resistant microorganisms. Plant flower extracts antioxidant activity was investigated against 2, 2-diphenyl-1-picryl hydrazyl radical by ultraviolet spectrophotometer (517 nm). Plant extracts displayed noteworthy radical scavenging activities at all concentrations (25–225 μg/mL). Notable activities were recorded by crude, chloroform and ethyl acetate extracts up to 88.27% at 225 μg/mL concentration. Compounds functional groups were examined by Fourier transform infrared spectroscopic studies. Alkanes, alkenes, alkyl halides, amines, carboxylic acids, amides, esters, alcohols, phenols, nitrocompounds, and aromatic compounds were identified by FTIR analysis. Thin layer chromatography bioautography was carried out for all plant extracts. Different bands were separated by various solvent systems. The results of the current study justify the use of Heliotropium bacciferum in traditional remedial herbal medicines. PMID:27597961

  12. Effects of iron deficiency on free radical scavenging enzymes in muscles of diabetic rats

    SciTech Connect

    Morrow, S.; Hegarty, P.V.J.

    1986-03-05

    Catalase, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) prevent free-radical mediated tissue damage. Diabetes increases, and low dietary intakes of iron decreases catalase activity in muscles. Therefore, the combined effects of diabetes and iron deficiency on the free radical enzyme scavenging system was studied. Male, weanling rats were injected with streptozotocin (65 mg/kg, I.V.) and fed diets containing either 35 ppm (Db+Fe) or 8 ppm (Db-Fe) iron. Sham-injected animals served as iron adequate (C+Fe) or iron deficient (C-Fe) controls. Heart, gastrocnemius, soleus and anterior tibialis muscles were dissected, weighed and analyzed for catalase, SOD and GSH-Px activities after 1,3 or 6 weeks on the respective diets. Muscles in Db+Fe and Db-Fe groups had elevated catalase activity after one week in the diabetic state. Conversely, catalase activity was depressed in the C-Fe animals. SOD and GSH-Px activities did not differ from control values for any experimental group. Treatment with insulin and/or iron returned catalase activity to control levels. These data indicate that iron deficiency does not inhibit responses of muscle catalase to the diabetic condition, and the diabetic condition exerts an effect on catalase which is independent of SOD and GSH-Px.

  13. Radical scavenging and antioxidant effects of Matricaria chamomilla polyphenolic-polysaccharide conjugates.

    PubMed

    Kolodziejczyk-Czepas, Joanna; Bijak, Michal; Saluk, Joanna; Ponczek, Michal B; Zbikowska, Halina M; Nowak, Pawel; Tsirigotis-Maniecka, Marta; Pawlaczyk, Izabela

    2015-01-01

    Matricaria chamomilla L. (MC), a member of the Asteraceae family, is one of the oldest medicinal plants, widely used worldwide for a variety of healing applications. Its recommendations, derived from both traditional and modern medicine, include numerous disorders such as inflammation, ulcers, wounds, gastrointestinal disorders, stomach ache, pharyngitis, rheumatic pain, as well as the other ailments. This work is focused on another aspect of the biological activity of chamomile polyphenolic-polysaccharide conjugates--their antioxidant properties in the protection of blood plasma components against in vitro oxidative stress. Measurements of DPPH and ABTS radical scavenging indicated considerable anti-free radical action of MC. Pre-incubation of blood plasma with MC considerably diminished the extent of ONOO(-)-induced oxidative modifications such as protein carbonyl groups, SH groups, 3-nitrotyrosine, as well as the formation of lipid hydroperoxides. The analysis of the FRAP assay result shows a considerable increase of ferric reducing ability of blood plasma in the presence of MC. The results obtained in this study indicate that polyphenolic-polysaccharide conjugates isolated from M. chamomilla substances possess antioxidant properties. The M. chamomilla macromolecular glycoconjugates may be useful in the creation of new natural-based medications or dietary supplements, helpful in the prevention and treatment of oxidative stress-mediated disorders. PMID:25285848

  14. [Pharmacological and clinical profile of the free radical scavenger edaravone as a neuroprotective agent].

    PubMed

    Tanaka, Masahiko

    2002-05-01

    The involvement of oxygen radical species has been implicated in ischemic and post-ischemic brain cell damage. Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one; M.W. 174.20, MCI-186, Radicut Injection) has an inhibitory effect on lipid peroxidation by scavenging free radicals and prevents vascular endothelial cell injury. In rat brain ischemic models, post-ischemic treatment with edaravone reduces .OH production and infarction of the ischemic penumbral area and suppresses delayed neuronal death. It also improves neurological deficits and diminishes deterioration of brain edema observed after ischemia. We investigated the efficacy and safety of edaravone in acute ischemic stroke patients. Edaravone improved the core neurological deficits, impaired activities of daily living, and disability, without serious safety problems. Edaravone was approved in Japan for the treatment of acute brain infarction within 24 h after onset in April, 2001. We hope that edaravone represents a promising neuroprotective agent that can contribute to the treatment of acute ischemic stroke. PMID:12061142

  15. Smelling lavender and rosemary increases free radical scavenging activity and decreases cortisol level in saliva.

    PubMed

    Atsumi, Toshiko; Tonosaki, Keiichi

    2007-02-28

    Free radicals/reactive oxygen species are related to many biological phenomena such as inflammation, aging, and carcinogenesis. The body possesses various antioxidative systems (free radical scavenging activity, FRSA) for preventing oxidative stress, and saliva contains such activity. In the present study, we measured the total salivary FRSA induced after the smelling of lavender and rosemary essential oils that are widely used in aromatherapy. Various physiologically active substances in saliva such as cortisol, secretory IgA, and alpha-amylase activity were found to be correlated with aroma-induced FRSA. The subjects (22 healthy volunteers) sniffed aroma for 5 min, and each subject's saliva was collected immediately. FRSA was measured using 1,1-diphenyl-2-picrylhydrazyl. The FRSA values were increased by stimulation with low concentrations (1000 times dilution) of lavender or by high-concentrations (10 times dilution) of rosemary. In contrast, both lavender and rosemary stimulations decreased cortisol levels. A significant inverse correlation was observed between the FRSA values and the cortisol levels with each concentration of rosemary stimulation. No significant changes were noted in sIgA or alpha-amylase. These findings clarify that lavender and rosemary enhance FRSA and decrease the stress hormone, cortisol, which protects the body from oxidative stress. PMID:17291597

  16. An efficient method for high-purity anthocyanin isomers isolation from wild blueberries and their radical scavenging activity.

    PubMed

    Chorfa, Nasima; Savard, Sylvain; Belkacemi, Khaled

    2016-04-15

    An efficient process for the purification of anthocyanin monomeric isomers from wild blueberries of Lake Saint-Jean region (Quebec, Canada) was developed and easy scalable at industrial purpose. The blueberries were soaked in acidified ethanol, filtered, and the filtrate was cleaned by solid phase extraction using silica gel C-18 and DSC-SCX cation-exchange resin. Anthocyanin-enriched elutes (87 wt.%) were successfully fractionated by preparative liquid chromatography. The major anthocyanins mono-galactoside, -glucoside and -arabinoside isomers of delphinidin, cyanidin, petunidin, peonidin and malvidin were isolated with a purity up to 100% according to their LC-MS and (1)H NMR spectra. The oxygen radical absorbance capacity (ORAC) of the obtained pure anthocyanins was evaluated. Delphinidin-3-galactoside has the highest capacity (13.062 ± 2.729 μmol TE/μmol), and malvidin-3-glucoside the lowest (0.851 ± 0.032 μmol TE/μmol). A mechanistic pathway preview is suggested for the anthocyanins scavenging free radical activity by hydrogen transfer. PMID:26675861

  17. Adaptive Neuro-Fuzzy Inference System Applied QSAR with Quantum Chemical Descriptors for Predicting Radical Scavenging Activities of Carotenoids.

    PubMed

    Jhin, Changho; Hwang, Keum Taek

    2015-01-01

    One of the physiological characteristics of carotenoids is their radical scavenging activity. In this study, the relationship between radical scavenging activities and quantum chemical descriptors of carotenoids was determined. Adaptive neuro-fuzzy inference system (ANFIS) applied quantitative structure-activity relationship models (QSAR) were also developed for predicting and comparing radical scavenging activities of carotenoids. Semi-empirical PM6 and PM7 quantum chemical calculations were done by MOPAC. Ionisation energies of neutral and monovalent cationic carotenoids and the product of chemical potentials of neutral and monovalent cationic carotenoids were significantly correlated with the radical scavenging activities, and consequently these descriptors were used as independent variables for the QSAR study. The ANFIS applied QSAR models were developed with two triangular-shaped input membership functions made for each of the independent variables and optimised by a backpropagation method. High prediction efficiencies were achieved by the ANFIS applied QSAR. The R-square values of the developed QSAR models with the variables calculated by PM6 and PM7 methods were 0.921 and 0.902, respectively. The results of this study demonstrated reliabilities of the selected quantum chemical descriptors and the significance of QSAR models. PMID:26474167

  18. Adaptive Neuro-Fuzzy Inference System Applied QSAR with Quantum Chemical Descriptors for Predicting Radical Scavenging Activities of Carotenoids

    PubMed Central

    Jhin, Changho; Hwang, Keum Taek

    2015-01-01

    One of the physiological characteristics of carotenoids is their radical scavenging activity. In this study, the relationship between radical scavenging activities and quantum chemical descriptors of carotenoids was determined. Adaptive neuro-fuzzy inference system (ANFIS) applied quantitative structure-activity relationship models (QSAR) were also developed for predicting and comparing radical scavenging activities of carotenoids. Semi-empirical PM6 and PM7 quantum chemical calculations were done by MOPAC. Ionisation energies of neutral and monovalent cationic carotenoids and the product of chemical potentials of neutral and monovalent cationic carotenoids were significantly correlated with the radical scavenging activities, and consequently these descriptors were used as independent variables for the QSAR study. The ANFIS applied QSAR models were developed with two triangular-shaped input membership functions made for each of the independent variables and optimised by a backpropagation method. High prediction efficiencies were achieved by the ANFIS applied QSAR. The R-square values of the developed QSAR models with the variables calculated by PM6 and PM7 methods were 0.921 and 0.902, respectively. The results of this study demonstrated reliabilities of the selected quantum chemical descriptors and the significance of QSAR models. PMID:26474167

  19. Synthesis and biological evaluation of piperic acid amides as free radical scavengers and α-glucosidase inhibitors.

    PubMed

    Takao, Koichi; Miyashiro, Takaki; Sugita, Yoshiaki

    2015-01-01

    A series of piperic acid amides (4-24, 29, 30) were synthesized and their 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and α-glucosidase inhibitory activities were evaluated. Among the synthesized compounds, the amides 11, 13 and 15, which contain o-methoxyphenol, catechol or 5-hydroxyindole moieties, showed potent DPPH free radical scavenging activity (11: EC50 140 µM; 13: EC50 28 µM; 15: EC50 20 µM). The amides 10, 18 and 23 showed higher inhibitory activity of α-glucosidase (10: IC50 21 µM; 18: IC50 21 µM; 23: IC50 12 µM). These data suggest that the hydrophobicity of the conjugated amines is an important determinant of α-glucosidase inhibitory activity. In addition, the amides 13 and 15 showed both potent DPPH free radical scavenging activity and α-glucosidase inhibitory activity (13: IC50 46 µM; 15: IC50 46 µM). This is the first report identifying the DPPH free radical scavenging and α-glucosidase inhibitory activities of piperic acid amides and suggests that these amides may serve as lead compounds for the development of novel α-glucosidase inhibitors with antioxidant activity. PMID:25948326

  20. Evaluation of antitumor, immunomodulatory and free radical scavenging effects of a new herbal prescription seaweed complex preparation

    NASA Astrophysics Data System (ADS)

    Liu, Xin; Shao, Changlun; Kong, Wenwen; Fang, Yuchun; Wang, Changyun

    2013-09-01

    Seaweed Complex Preparation (SCP) is a clinical traditional Chinese medicine preparation which is composed of seven traditional Chinese herbs, and it has been used for treatment of lung cancer, liver cancer and digestive cancer. However, little information is available about the pharmacodynamic basis. The antitumor, immunomodulatory and free radical scavenging effects of SCP were evaluated in this study. Transplanted tumor in vivo method was used to determine the antitumor effect. The effects on splenocyte proliferation and phagocytosis of macrophages in tumor-bearing mice were measured by the MTT method and the phagocytizing cock red blood cell (CRBC) method respectively. The scavenging activities of SCP on DPPH and hydroxyl radicals in vitro were investigated. It was found that the medium-dose and high-dose of SCP could significantly inhibit the growth of transplanted hepatic tumor of murine hepatocarcinoma cell line H22, and promote proliferation of splenocytes and phagocytosis of macrophages. SCP possessed noticeable scavenging activities on DPPH and hydroxyl radicals. The antitumor effects of SCP might be achieved by improving immune system and scavenging free radicals, which is in accordance with the viewpoint of traditional Chinese medicine in promoting the body resistance and eliminating pathogenic factors for cancer treatment.

  1. Screening and evaluation of antioxidant activity of some amido-carbonyl oxime derivatives and their radical scavenging activities.

    PubMed

    Ozen, Tevfik; Taş, Murat

    2009-10-01

    The antioxidant activity of some amido-carbonyl oximes containing a C=O and -NH-R adjacent to the oxime group, [Phenyl-C(=O)-C(=N-OH)-N(-H)-Phenyl(-R)] where R= H, 4-chloro, 4-methyl, 4-methoxy, 3,4-dichloro, 3,4-dimethyl, 3-chloro-4-dimethyl, 3-chloro-4-methoxy, naphthyl and an amido-carbonyl dioxime were investigated in vitro by ferric thiocyanate, total reducing power by potassium ferricyanide reduction, 1,1-diphenyl-2- picryl-hydrazyl (DPPH(.)) free radical scavenging, ferrous ions chelating, superoxide anion radical scavenging and hydrogen peroxide scavenging activity assays. The results indicated that the amido-carbonyl oximes have powerful antioxidant capacity. PMID:19772487

  2. Contribution of flavonoids to the overall radical scavenging activity of olive (Olea europaea L.) leaf polar extracts.

    PubMed

    Goulas, Vlassios; Papoti, Vassiliki T; Exarchou, Vassiliki; Tsimidou, Maria Z; Gerothanassis, Ioannis P

    2010-03-24

    The contribution of flavonoids to the overall radical scavenging activity of olive leaf polar extracts, known to be good sources of oleuropein related compounds, was examined. Off line and on line HPLC-DPPH(*) assays were employed, whereas flavonoid content was estimated colorimetrically. Individual flavonoid composition was first assessed by RP-HPLC coupled with diode array and fluorescence detectors and verified by LC-MS detection system. Olive leaf was found a robust source of flavonoids regardless sampling parameters (olive cultivar, leaf age or sampling date). Total flavonoids accounted for the 13-27% of the total radical scavenging activity assessed using the on line protocol. Luteolin 7-O-glucoside was one of the dominant scavengers (8-25%). Taking into consideration frequency of appearance the contribution of luteolin (3-13%) was considered important, too. Our findings support that olive leaf, except for oleuropein and related compounds, is also a stable source of bioactive flavonoids. PMID:20166722

  3. Immobilized transition metal-based radical scavengers and their effect on durability of Aquivion® perfluorosulfonic acid membranes

    NASA Astrophysics Data System (ADS)

    D'Urso, C.; Oldani, C.; Baglio, V.; Merlo, L.; Aricò, A. S.

    2016-01-01

    A simple and broadly applicable preparation procedure to obtain silica-supported transition metal (namely Cr, Co and Mn)-based radical scavengers, containing sulfonic acid functionalities, is reported. These systems are widely characterised in terms of structure, bulk and surface composition and morphology by X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), X-Ray Photoelectron Spectroscopy (XPS) and Transmission Electron Microscopy (TEM). The scavenger material is loaded in ePTFE reinforced membranes prepared from Aquivion® perfluorosulfonic acid (PFSA) dispersions. All these composite membranes show longer lifetime in Accelerated Stress Tests (AST) and reduced fluoride release in Fenton's tests than the scavenger-free membranes without any loss in electrochemical performance. The Cr-scavenger-based polymer electrolyte shows a three-time larger stability than the pristine membrane.

  4. 2,2'-Azobis(isobutyronitrile)-derived alkylperoxyl radical scavenging activity assay of hydrophilic antioxidants by employing EPR spin trap method

    PubMed Central

    Kohri, Shunji; Fujii, Hirotada

    2013-01-01

    As interest in the study of antioxidant intake from foods and other agricultural products increases, methods for performing radical scavenging activity assays based on the electron paramagnetic resonance spectroscopic method, in which there is no interference from the sample color and turbidity, are required. In this study, we have developed a rapid and simple electron paramagnetic resonance based assay to evaluate the alkylperoxyl radical scavenging activity of several antioxidants. The alkylperoxyl radical species was generated by the photolysis of azo-radical initiator 2,2'-azobis(isobutyronitrile), in which the radical generation rate and period were controlled by the illumination light. The relative alkylperoxyl radical scavenging activity was obtained by a simple formula of competing reaction of antioxidant and spin trap toward the oxygen radical. The scavenging activities toward alkylperoxyl radical and alkoxy radical species were evaluated in six antioxidants. Although quercetin showed the highest activity toward both radicals, the order of the relative activities in the other antioxidants was different mutually between the alkylperoxyl radical and the alkoxyl radical. This alkylperoxyl radical scavenging activity assay based on electron paramagnetic resonance spectroscopy is useful for evaluation of colored and turbid food samples. PMID:24249966

  5. Sugars as hydroxyl radical scavengers: proof-of-concept by studying the fate of sucralose in Arabidopsis.

    PubMed

    Matros, Andrea; Peshev, Darin; Peukert, Manuela; Mock, Hans-Peter; Van den Ende, Wim

    2015-06-01

    Substantial formation of reactive oxygen species (ROS) is inevitable in aerobic life forms. Due to their extremely high reactivity and short lifetime, hydroxyl radicals are a special case, because cells have not developed enzymes to detoxify these most dangerous ROS. Thus, scavenging of hydroxyl radicals may only occur by accumulation of higher levels of simple organic compounds. Previous studies have demonstrated that plant-derived sugars show hydroxyl radical scavenging capabilities during Fenton reactions with Fe(2+) and hydrogen peroxide in vitro, leading to formation of less detrimental sugar radicals that may be subject of regeneration to non-radical carbohydrates in vivo. Here, we provide further evidence for the occurrence of such radical reactions with sugars in planta, by following the fate of sucralose, an artificial analog of sucrose, in Arabidopsis tissues. The expected sucralose recombination and degradation products were detected in both normal and stressed plant tissues. Oxidation products of endogenous sugars were also assessed in planta for Arabidopsis and barley, and were shown to increase in abundance relative to the non-oxidized precursor during oxidative stress conditions. We concluded that such non-enzymatic reactions with hydroxyl radicals form an integral part of plant antioxidant mechanisms contributing to cellular ROS homeostasis, and may be more important than generally assumed. This is discussed in relation to the recently proposed roles for Fe(2+) and hydrogen peroxide in processes leading to the origin of metabolism and the origin of life. PMID:25891826

  6. Flavour characterisation and free radical scavenging activity of coriander (Coriandrum sativum L.) foliage.

    PubMed

    Priyadarshi, Siddharth; Khanum, Hafeeza; Ravi, Ramasamy; Borse, Babasaheb Baskarrao; Naidu, Madeneni Madhava

    2016-03-01

    The primary objective was to characterize Indian Coriandrum sativum L. foliage (Vulgare alef and Microcarpum DC varieties) and its radical scavenging activity. Foliage of Vulgare alef and Microcarpum DC contained ascorbic acid (1.16 ± 0.35 and 1.22 ± 0.54 mg/g), total carotenoids (1.49 ± 0.38 and 3.08 ± 1.2 mg/g), chlorophyll 'a' (8.23 ± 2.4 and 12.18 ± 2.9 mg/g), chlorophyll 'b' (2.74 ± 0.8 and 4.39 ± 1.3 mg/g) and total chlorophyll (10.97 ± 2.6 and 16.57 ± 3.2 mg/g). The polyphenol content was 26.75 ± 1.85 and 30.00 ± 2.64 mg/g in Vulgare alef and Microcarpum DC, respectively. Ethanol extracts (200 ppm) of alef and Microcarpum DC showed higher radical scavenging activity of 42.05 ± 2.42 % and 62.79 ± 1.36 % when compared with 95 % butylated hydroxyanisole. The principal component analysis results indicated that e-nose can distinguish the volatiles effectively. Quantitative descriptive sensory analysis showed that Microcarpum DC variety is superior to Vulgare alef variety. Nearly 90 % of the flavour compounds present were identified by GC-MS in both varieties. The principal component identified in both the varieties were decanal (7.645 and 7.74 %), decanol < n- > (25.12 and 39.35 %), undecanal (1.20 and 1.75 %), dodecanal (7.07 and 2.61 %), tridecen-1-al < 2E > (6.67 and 1.21 %), dodecen-1-ol < 2E- > (16.68 and 8.05 %), 13-tetradecenal (9.53 and 8.60 %), tetradecanal (5.61 and 4.35 %) and 1-octadecanol (1.25 and 3.67 %). PMID:27570292

  7. Anti-inflammatory, gastroprotective, free-radical-scavenging, and antimicrobial activities of hawthorn berries ethanol extract.

    PubMed

    Tadić, Vanja M; Dobrić, Silva; Marković, Goran M; Dordević, Sofija M; Arsić, Ivana A; Menković, Nebojsa R; Stević, Tanja

    2008-09-10

    Hawthorn [Crataegus monogyna Jacq. and Crataegus oxyacantha L.; sin. Crataegus laevigata (Poiret) DC., Rosaceae] leaves, flowers, and berries are used in traditional medicine in the treatment of chronic heart failure, high blood pressure, arrhythmia, and various digestive ailments, as well as geriatric and antiarteriosclerosis remedies. According to European Pharmacopoeia 6.0, hawthorn berries consist of the dried false fruits of these two species or their mixture. The present study was carried out to test free-radical-scavenging, anti-inflammatory, gastroprotective, and antimicrobial activities of hawthorn berries ethanol extract. Phenolic compounds represented 3.54%, expressed as gallic acid equivalents. Determination of total flavonoid aglycones content yielded 0.18%. The percentage of hyperoside, as the main flavonol component, was 0.14%. With respect to procyanidins content, the obtained value was 0.44%. DPPH radical-scavenging capacity of the extract was concentration-dependent, with EC50 value of 52.04 microg/mL (calculation based on the total phenolic compounds content in the extract). Oral administration of investigated extract caused dose-dependent anti-inflammatory effect in a model of carrageenan-induced rat paw edema. The obtained anti-inflammatory effect was 20.8, 23.0, and 36.3% for the extract doses of 50, 100, and 200 mg/kg, respectively. In comparison to indomethacin, given in a dose producing 50% reduction of rat paw edema, the extract given in the highest tested dose (200 mg/kg) showed 72.4% of its activity. Gastroprotective activity of the extract was investigated using an ethanol-induced acute stress ulcer in rats with ranitidine as a reference drug. Hawthorn extract produced dose-dependent gastroprotective activity (3.8 +/- 2.1, 1.9 +/- 1.7, and 0.7 +/- 0.5 for doses of 50, 100, and 200 mg/kg, respectively), with the efficacy comparable to that of the reference drug. Antimicrobial testing of the extract revealed its moderate bactericidal

  8. Effects of hydroxyl radical scavengers KCN and CO on ultraviolet light-induced activation of crude soluble guanylate cyclase

    SciTech Connect

    Karlsson, J.O.; Axelsson, K.L.; Andersson, R.G.

    1985-01-01

    The crude soluble guanylate cyclase (GC) from bovine mesenteric artery was stimulated by ultraviolet (UV) light (366 nm). Addition of free radical scavengers, dimethylsulfoxide or superoxide dismutase and/or catalase to the GC assay did not abolish the stimulatory effect of UV light. On the contrary, the UV light-induced activation was enhanced in the presence of these scavengers. KCN (1 mM) did not affect the UV light-induced activation, while 0.1 mM of CO potentiated the activation. These results may indicate that UV light is operating through a direct interaction with the ferrous form of the GC-heme.

  9. Determination of in vitro free radical scavenging and antiproliferative effect of Pennisetum alopecuroides on cultured A549 human lung cancer cells

    PubMed Central

    Mathew, Githa Elizabeth; Mathew, Bijo; Gokul, S.; Krishna, Rahul; Farisa, M. P.

    2015-01-01

    Context: Pennisetum alopecuroides (Poaceae) is a grass predominantly distributed in tropics and sub tropics. It is used as a cattle feed in many regions. Aim: The objective of the present study was to investigate the in vitro free radical scavenging and antiproliferative activity of ethanol extract of P. alopecuroides (EEPA) on cultured A549 human lung cancer cell lines. Settings and Design: The anti-oxidant activity of ethanol extract was evaluated at dose level 12.5, 25, 50, 100, and 200 μg/ml. The in vitro antiproliferative activity was measured at doses of 10, 50, and 100 μg/ml. Materials and Methods: The free radical scavenging activity of the EEPA was determined by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) method and in vitro antiproliferative activity on A549 human lung cancer cells was conducted by using MTT assay method. Results: The phytochemical screening revealed that the P. alopecuroides contained alkaloids, tannins, saponins, and flavonoids as the major secondary metabolites. The IC50 value of DPPH scavenging activity was found to be 44.41 μg/ml and 31.02 μg/ml  for a mixture of EEPA and standard ascorbic acid, respectively. In vitro MTT assay showed that EEPA had anti-proliferation effects on A549 cells in a dose dependent manner. Conclusions: This is the 1st time a pharmacological exploration of P. alopecuroides grasses has been conducted. We have shown that P. alopecuroides exhibits good free radical scavenging and strong in vitro cytotoxic activities against human lung cancer cell lines. PMID:26120234

  10. Radical scavenging and radiomodulatory effects of Psoralea corylifolia Linn. substantiated by in vitro assays and EPR spectroscopy.

    PubMed

    Arora, Rajesh; Dhaker, Atlar Singh; Adhikari, Manish; Sharma, Jyoti; Chawla, Raman; Gupta, Damodar; Zheleva, Antoaneta; Karamalakova, Yanka; Kumar, Raj; Sharma, Raj K; Sharma, Ashok; Sultana, Sarwat; Sharma, Rakesh K; Tripathi, Rajendra P; Gadjeva, Veselina

    2011-01-01

    The present study is the first report of the radiomodulatory effects of Psoralea corylifolia Linn. The extract (IBG-RA-26) prepared from P. corylifolia was chemically analysed by HPLC, LC-MS/MS and NMR. The total polyphenolic content of IBG-RA-26 was 0.287 mg/ml of quercetin equivalents. IBG-RA-26 exhibited a dose-dependent increase in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. It exhibited comparable (> 50%) site-specific and non-site-specific hydroxyl radical scavenging activity in higher concentration ranges (500-1000 microg/ml), while at lower concentrations (5-50 microg/ml) it exhibited significantly (p < 0.05) higher non-site-specific scavenging ability compared to site-specific activity. Nitric oxide scavenging activity of IBG-RA-26 (5-1000 microg/ml) increased in a concentration-dependent manner, while maximum superoxide ion scavenging ability (79%) was observed at 50 microg/ml. The electron donation potential of IBG-RA-26 was found to be higher than that of ascorbic acid at lower concentrations (up to 5 microg/ml). Analysis of the ability of IBG-RA-26 to protect membranes against gamma-radiation, utilizing an artificial membrane system (liposome), revealed a significant (p < 0.05) decrease in the formation of malondialdehyde (MDA) as a function of the concentration of IBG-RA-26. Radiation-induced lysis of human erythrocytes was monitored and efficacy of IBG-RA-26 was tested in the concentration range 25-1000 microg/ml, with significant protective efficacy observed in the range 25-50 microg/ml. IBG-RA-26 rendered significant (p < 0.05) protection against radiation (0.25 kGy)-induced DNA damage. EPR spectroscopy was used to investigate the DPPH radical scavenging capacity of IBG-RA-26. IBG-RA-26 exhibited a good DPPH radical scavenging capacity in a concentration-dependent manner. By direct EPR spectroscopy we have also demonstrated the possible formation of free radical species in a solution of IBG-RA-26. The wide spectrum of

  11. A novel method to measure both the reductive and the radical scavenging activity in a linoleic acid model system.

    PubMed

    Lindenmeier, Michael; Burkon, Alexander; Somoza, Veronika

    2007-12-01

    The aim of this study was to develop a combined method for measuring the total antioxidant activity, the reductive and the radical scavenging activity. Linoleic acid was used as the substrate for an iron-initiated lipid peroxidation to measure the total antioxidant activity. In addition, methyl esters of linoleic acid hydroperoxides were used as substrates to measure the reductive antioxidant activity. The radical scavenging antioxidant activity was calculated by subtracting the reductive antioxidative activity from the total antioxidative activity. As representative examples, the antioxidants alpha-tocopherol, ascorbic acid, trans-resveratrol and L-glutathione as well as commonly used food additives such as 2(3)-tert-butyl-4-hydroxyanisole (BHA) and 2,6-bis(1,1-dimethylethyl)-4-methylphenol (BHT) were analyzed. The results for the novel antioxidation test showed that alpha-tocopherol, BHA and BHT are primarily acting as radical scavengers, whereas ascorbic acid and L-glutathione show a strong reductive capacity. As linoleic acid as well as its hydroperoxides both are present in foods and in the organism, the test presented here can be considered representative of radical reactions occurring in food matrixes and in vivo. Further experiments are required to document the comprehensive applicability in foods and in vivo. PMID:17680718

  12. Optimization of Ultrasonic-Assisted Extraction and Radical-Scavenging Capacity of Phenols and Flavonoids from Clerodendrum cyrtophyllum Turcz Leaves

    PubMed Central

    Zhou, Jing; Zheng, Xiaoxue; Yang, Qi; Liang, Zhenyi; Li, Donghai; Yang, Xiaobo; Xu, Jing

    2013-01-01

    Ultrasonic-assisted extraction (UAE) was developed to extract phenolic and flavonoid antioxidants from Clerodendrum cyrtophyllum Turcz leaves. The optimal experimental parameters for antioxidant extraction from C. cyrtophyllum leaves were measured using single-factor experimentation combined with response surface methodology (RSM). Total phenolic content (TPC) and total flavonoid content (TFC) assays were used to quantify antioxidant compounds. Next, antioxidant radical scavenging capacity was measured using 2,2′-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′ -azino-bis(3-ethylbenzothiazoline-6-sulphonicacid) (ABTS) radicals. Optimized extraction conditions for UAE from C. cyrtophyllum leaves were as follows: 60.9% ethanol, 85.4 min, and 63.3°C for maximal TPC extraction (16.8±0.2 mg GAE/g DW); 67.7% ethanol, 82.9 min, and 63.0°C for maximal TFC extraction (49.3±0.4 mg RT/g DW); 48.8% ethanol, 85.1 min, and 63.9°C for maximal DPPH radical-scavenging capacity (86.8±0.2%); and 50.6% ethanol, 81.3 min, and 63.4°C for maximal ABTS radical-scavenging capacity (92.9±0.5%). Ethanol concentration was the most important factor in the extraction process. Our work offers optimal extraction conditions for C. cyrtophyllum as a potential source of natural antioxidants. PMID:23874607

  13. Screening of radical scavenging activity and polyphenol content of Bulgarian plant species

    PubMed Central

    Nikolova, Milena

    2011-01-01

    Background: Discovery of new plant species with antioxidant properties is a priority of many research teams. Most of the species included in this study are unstudied for antioxidant properties, but they are taxonomically related to reference plants with well-documented antioxidant activity. Materials and Methods: Free radical scavenging activity of plant extracts was evaluated using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. An aluminum chloride colorimetric method was used for flavonoid determination. The amount of phenolic compounds in the extracts was estimated by using the Folin–Ciocalteu reagent. Results: As a result of screening, it was found that the significant antioxidant properties possess several unstudied until now plant species (Veronica bellidioides L., V. kellereri Deg. et Urm, V. vindobonensis (M. Fisher) M. Fisher, V. beccabunga L., V. rhodopaea L., V. austriaca (Velen.) Degen., Clinopodium vulgare L., Stachysrecta L., Clematis vitalba L., and Xeranthemum annum L.). The antioxidant potential of the new species is comparable to that of reference medicinal plants. Conclusions: The existing data presented here provide new information for antioxidant potential of plant species that have not been traditionally used as medicinal plants. PMID:22224049

  14. Synergistic radical scavenging potency of curcumin-in-β-cyclodextrin-in-nanomagnetoliposomes.

    PubMed

    Aadinath, W; Bhushani, Anu; Anandharamakrishnan, C

    2016-07-01

    Curcumin is a highly potent nutraceutical associated with various health benefits. However, its hydrophobic nature affects its bioavailability and bioactivity, and limits nutraceutical applications. Drug-in-cyclodextrin-in-liposome has the ability to mask the hydrophobic nature of drug and achieve better encapsulation. Also, encapsulating iron oxide nanoparticles (IONPs) within liposomes endow additional beneficial functionalities of IONPs. In the present study, curcumin-β-cyclodextrin inclusion complex (IC) and IONPs were co-encapsulated within liposomes (curcumin-in-β-cyclodextrin-in-nanomagnetoliposomes) to achieve the synergistic antioxidant potential of curcumin and IONPs. IC of curcumin-β-cyclodextrin was prepared by a simple rapid method and successful inclusion was confirmed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). Mean diameter of IONPs was found to be 180nm and X-ray diffraction pattern confirmed the formation of hematite nanoparticles. Band gap energy calculated using absorption spectra was 2.25eV, which falls in close proximity with the theoretically calculated values of hematite. Mean diameter of curcumin-in-β-cyclodextrin-in-nanomagnetoliposomes was 67nm and encapsulation efficiency of curcumin was found to be 71%. Further, the co-encapsulated particles possessed significantly low IC50 value (64.7791μg/ml, p<0.01) compared to conventional curcumin liposome and IONPs, indicating its synergistically enhanced radical scavenging property. PMID:27127056

  15. Formulation of microspheres containing Crataegus monogyna Jacq. extract with free radical scavenging activity.

    PubMed

    Lucconi, Giulia; Chlapanidas, Theodora; Martino, Emanuela; Gaggeri, Raffaella; Perteghella, Sara; Rossi, Daniela; Faragò, Silvio; Vigo, Daniele; Faustini, Massimo; Collina, Simona; Torre, Maria Luisa

    2014-02-01

    Extracts of Crataegus monogyna Jacq. (hawthorn) show an interesting free radical scavenging (FRS) effect, related to their flavonoids content. Unfortunately, their oral administration is affected by their low bioavailability. The aim of this work is to obtain a multiparticulate drug delivery system for hawthorn extracts for oral administration. The extracts from flowering tops (FL) or fruits (FR) of hawthorn were obtained with maceration, using ethanol as an extraction solvent, and their antioxidant activity was evaluated. FL extract showed the highest FRS activity (EC50 3.72 ± 1.21 µg/ml), so it was selected to prepare microparticulate systems by a spray-drying technique, which were characterized by granulometric analysis, scanning electron microscopy-energy dispersive X-ray spectroscopy, confocal fluorescence microscopy and hyperoside content. Antioxidant activity was evaluated before and after gastrointestinal transit in vitro simulation. Results indicate that the microparticulate systems maintained the antioxidant activity of hawthorn also after gastrointestinal transit in vitro simulation, exhibiting properties suitable for oral administration. PMID:23301945

  16. Metabolic Profiles and Free Radical Scavenging Activity of Cordyceps bassiana Fruiting Bodies According to Developmental Stage

    PubMed Central

    Hyun, Sun-Hee; Lee, Seok-Young; Sung, Gi-Ho; Kim, Seong Hwan; Choi, Hyung-Kyoon

    2013-01-01

    The metabolic profiles of Cordyceps bassiana according to fruiting body developmental stage were investigated using gas chromatography-mass spectrometry. We were able to detect 62 metabolites, including 48 metabolites from 70% methanol extracts and 14 metabolites from 100% n-hexane extracts. These metabolites were classified as alcohols, amino acids, organic acids, phosphoric acids, purine nucleosides and bases, sugars, saturated fatty acids, unsaturated fatty acids, or fatty amides. Significant changes in metabolite levels were found according to developmental stage. Relative levels of amino acids, purine nucleosides, and sugars were higher in development stage 3 than in the other stages. Among the amino acids, valine, isoleucine, lysine, histidine, glutamine, and aspartic acid, which are associated with ABC transporters and aminoacyl-tRNA biosynthesis, also showed higher levels in stage 3 samples. The free radical scavenging activities, which were significantly higher in stage 3 than in the other stages, showed a positive correlation with purine nucleoside metabolites such as adenosine, guanosine, and inosine. These results not only show metabolic profiles, but also suggest the metabolic pathways associated with fruiting body development stages in cultivated C. bassiana. PMID:24058459

  17. Physicochemical characterisation and radical-scavenging activity of Cucurbitaceae seed oils.

    PubMed

    Jorge, Neuza; da Silva, Ana Carolina; Malacrida, Cassia Roberta

    2015-01-01

    Oils extracted from Cucurbitaceae seeds were characterised for their fatty acid and tocopherol compositions. In addition, some physicochemical characteristics, total phenolic contents and the radical-scavenging activities were determined. Oil content amounted to 23.9% and 27.1% in melon and watermelon seeds, respectively. Physicochemical characteristics were similar to those of other edible oils and the oils showed significant antioxidant activities. Fatty acid composition showed total unsaturated fatty acid content of 85.2-83.5%, with linoleic acid being the dominant fatty acid (62.4-72.5%), followed by oleic acid (10.8-22.7%) and palmitic acid (9.2-9.8%). The oils, especially watermelon seed oil, showed high total tocopherol and phenolic contents. The γ-tocopherol was the predominant tocopherol in both oils representing 90.9 and 95.6% of the total tocopherols in melon and watermelon seed oils, respectively. The potential utilisation of melon and watermelon seed oils as a raw material for food, chemical and pharmaceutical industries appears to be favourable. PMID:25697079

  18. Isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from Tibouchina semidecandra L.

    PubMed

    Sirat, Hasnah M; Rezali, Mohd Fazlin; Ujang, Zanariah

    2010-10-13

    Phytochemical and bioactivity studies of the leaves and stem barks of Tibouchina semidecandra L. have been carried out. The ethyl acetate extract of the leaves yielded four flavonoid compounds, identified as quercetin, quercetin 3-O-α-l-(2''-O-acetyl) arabinofuranoside, avicularin, and quercitrin, while the stem barks gave one ellagitannin, identified as 3,3'-O-dimethyl ellagic acid 4-O-α-l-rhamnopyranoside. Evaluation of the antioxidative activity on the crude extracts and pure compounds by electron spin resonance (ESR) and ultraviolet-visible (UV-vis) spectrophotometric assays showed that the pure isolated polyphenols and the EtOAc extract possessed strong antioxidative capabilities. Quercetin was found to be the most active radical scavenger in DPPH-UV and ESR methods with SC(50) values of 0.7 μM ± 1.4 and 0.7 μM ± 0.6 μM, respectively, in the antioxidant assay. A combination of quercetin and quercitrin was tested for synergistic antioxidative capacity;, however, there was no significant improvement observed. Quercetin also exhibited strong antityrosinase activity with a percent inhibition of 95.0% equivalent to the positive control, kojic acid, in the tyrosinase inhibition assay. PMID:20809630

  19. Micronization of Taxifolin by Supercritical Antisolvent Process and Evaluation of Radical Scavenging Activity

    PubMed Central

    Zu, Shuchong; Yang, Lei; Huang, Jinming; Ma, Chunhui; Wang, Wenjie; Zhao, Chunjian; Zu, Yuangang

    2012-01-01

    The aim of this study was to prepare micronized taxifolin powder using the supercritical antisolvent precipitation process to improve the dissolution rate of taxifolin. Ethanol was used as solvent and carbon dioxide was used as an antisolvent. The effects of process parameters, such as temperature (35–65 °C), pressure (10–25 MPa), solution flow rate (3–6 mL/min) and concentration of the liquid solution (5–20 mg/mL) on the precipitate crystals were investigated. With a lower temperature, a stronger pressure and a lower concentration of the liquid solution, the size of crystals decreased. The precipitation temperature, pressure and concentration of taxifolin solution had a significant effect. However, the solution flow rate had a negligible effect. It was concluded that the physicochemical properties and dissolution rate of crystalline taxifolin could be improved by physical modification such as particle size reduction using the supercritical antisolvent (SAS) process. Further, the SAS process was a powerful methodology for improving the physicochemical properties and radical scavenging activity of taxifolin. PMID:22942740

  20. Synthesis, spectral characterization, DNA interaction, radical scavenging and cytotoxicity studies of ruthenium(II) hydrazone complexes.

    PubMed

    Mohanraj, Maruthachalam; Ayyannan, Ganesan; Raja, Gunasekaran; Jayabalakrishnan, Chinnasamy

    2016-05-01

    Three new ruthenium(II) complexes with hydrazone ligands, furan-2-carboxylic acid (2,4-dihydroxy-benzylidene)-hydrazide (HL(1)), furan-2-carboxylic acid [4-(ethyl-propyl-amino)-2-hydroxy-benzylidene]-hydrazide (HL(2)) and furan-2-carboxylic acid (3-ethoxy-2-hydroxy-benzylidene)-hydrazide (HL(3)) were synthesized and characterized by various spectro-analytical techniques. The hydrazone ligands act as a tridendate ligand with ONO as the donor sites and are preferably found in the enol form in all the complexes. The molecular structure of the ligands was determined by single crystal X-ray diffraction technique. The interaction of the ligands and the complexes with CT-DNA were evaluated by an absorption titration method which revealed that the compounds interact with CT-DNA through intercalation. Gel electrophoresis assay demonstrated the ability of the complexes to cleave the calf thymus DNA hydrolytically. Antioxidant studies showed that the ruthenium(II) complexes have a strong radical-scavenging properties. Further, the cytotoxic effect of the compounds examined on cancerous cell lines showed that the complexes exhibited substantial anticancer activity. PMID:26974577

  1. Dephenolization, dearomatization and detoxification of olive mill wastewater with sonication combined with additives and radical scavengers.

    PubMed

    Sponza, Delia Teresa; Oztekin, Rukiye

    2014-05-01

    In this study, the effects of some additives [manganese (III) oxide (Mn3O4), Cu(+2), Fe(0) and potassium iodate (KIO3)] and some radical scavengers [sodium carbonate (Na2CO3), perfluorohexane (C6F14) and t-butyl alcohol (C4H10O)] on the sonication of olive mill effluent wastewater (OMW) were investigated since the wastewaters of this industry are removed with low efficiencies. The maximum total phenol and total aromatic amines (TAAs) removal efficiencies were 88% and 79%, respectively, at 60°C with only 150 min sonication. The maximum phenol removal was found as 98% with 19 mg L(-1) perfluorohexane and 5 mg L(-1) Fe(0) while the maximum TAAs removal was 99% with 16 mg L(-1) KIO3. Catechol, tyrosol, quercetin, caffeic acid, 4-methyl catechol, 2-phenylphenol (2-PHE) and 3-phenyl phenol (3-PHE) were detected as phenol intermediates while trimethlyaniline, aniline, o-toluidine, o-anisidine, dimethylaniline, ethylbenzene and durene were identified as TAAs in the OMW. The maximum acute toxicity removals were 96% and 99% in Vibrio fischeri and Daphnia magna, respectively. Total phenol, TAAs and the toxicity in an OMW were removed efficiently and cost-effectively through sonication. PMID:24315030

  2. Analgesic and free radical scavenging activities of hydromethanolic extract of Crateva adansonii stem bark

    PubMed Central

    Udeh, Nkeiruka E.; Onoja, Samuel O.

    2015-01-01

    Background: Crateva adansonii is a moderately sized deciduous tree found throughout the tropics especially along the river banks. This study was aimed at the evaluation of the analgesic and antioxidant activities of the methanolic extract of C. adansonii stem-bark. Methods: The analgesic activity of Crateva extract was investigated using both chemical and thermal models of nociception in rodents while the antioxidant activity was evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) photometric model. Results: The extract produced a minute concentration-dependent increase in free radical scavenging activities. The extract (100, 200, and 400 mg/kg) caused a significant (P < 0.05) dose-dependent reduction in the number of writhing in treated rats when compared to the negative control. The extract at 100, 200, 400 mg/kg, and pentazocine (3 mg/kg) increased the pain reaction time in the treated rats by 58.05%, 66.67%, 94.76%, and 79.40%, respectively, when compared to the negative control. Conclusion: The C. adansonii stem bark possesses analgesic activity against peripheral and central mediated pain sensation and also antioxidant properties. This study justifies the ethnomedical use of C. adansonii in pain treatment. PMID:26401412

  3. Investigation of the influence of hydroxy groups on the radical scavenging ability of polyphenols.

    PubMed

    Thavasi, Velmurugan; Leong, Lai Peng; Bettens, Ryan Phillip Anthony

    2006-04-13

    Recently, O-H bond dissociation enthalpies (BDEs) have been successfully used to express the free radical scavenging ability of polyphenolic antioxidants. In this work, the BDEs of phenol, catechol, resorcinol, hydroquinone, pyrogallol, phloroglucinol, 1,2,4-benzenetriol, and 5-hydroxypyrogallol have been calculated at B3LYP/6-311G++(3df, 3pd) and used to elucidate the effect of OH groups. Increasing the number of OH groups in the adjacent (vicinal) position decreases the BDE of phenols. Increasing the number of O-H groups in the alternative position C(1,3) as in resorcinol and C(1,3,5) as in phloroglucinol does not show any notable change in the BDEs when compared to that of OH in C(1) as in phenol. 5-Hydroxypyrogallol has the smallest BDE (250.3 kJ mol(-1)) followed by pyrogallol (289.4 kJ mol(-1)), then 1,2,4-benzenetriol (294.8 kJ mol(-1)), and then catechol (312.8 kJ mol(-1)). Overall, our results indicated that the presence of ortho and para hydroxy groups reduces the BDEs. An intramolecular hydrogen bond (IHB) develops due to the ortho arrangement of OH's and plays a dominant role in decreasing the BDEs. This key study on phenols showed that the reactive order of OH position in the benzene ring is the following: 5-hydroxypyrogallol > pyrogallol > 1,2,4-benzenetriol > catechol > hydroquinone > phenol approximately resorcinol approximately phloroglucinol. PMID:16599462

  4. A quantitative structure-activity relationship model for radical scavenging activity of flavonoids.

    PubMed

    Om, A; Kim, J H

    2008-03-01

    A quantitative structure-activity relationship (QSAR) study has been carried out for a training set of 29 flavonoids to correlate and predict the 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity (RSA) values obtained from published data. Genetic algorithm and multiple linear regression were employed to select the descriptors and to generate the best prediction model that relates the structural features to the RSA activities using (1) three-dimensional (3D) Dragon (TALETE srl, Milan, Italy) descriptors and (2) semi-empirical descriptor calculations. The predictivity of the models was estimated by cross-validation with the leave-one-out method. The result showed that a significant improvement of the statistical indices was obtained by deleting outliers. Based on the data for the compounds used in this study, our results suggest a QSAR model of RSA that is based on the following descriptors: 3D-Morse, WHIM, and GETAWAY. Therefore, satisfactory relationships between RSA and the semi-empirical descriptors were found, demonstrating that the energy of the highest occupied molecular orbital, total energy, and energy of heat of formation contributed more significantly than all other descriptors. PMID:18361735

  5. Mechanism of Action of Sulforaphane as a Superoxide Radical Anion and Hydrogen Peroxide Scavenger by Double Hydrogen Transfer: A Model for Iron Superoxide Dismutase.

    PubMed

    Prasad, Ajit Kumar; Mishra, P C

    2015-06-25

    The mechanism of action of sulforaphane as a scavenger of superoxide radical anion (O2(•-)) and hydrogen peroxide (H2O2) was investigated using density functional theory (DFT) in both gas phase and aqueous media. Iron superoxide dismutase (Fe-SOD) involved in scavenging superoxide radical anion from biological media was modeled by a complex consisting of the ferric ion (Fe(3+)) attached to three histidine rings. Reactions related to scavenging of superoxide radical anion by sulforaphane were studied using DFT in the presence and absence of Fe-SOD represented by this model in both gas phase and aqueous media. The scavenging action of sulforaphane toward both superoxide radical anion and hydrogen peroxide was found to involve the unusual mechanism of double hydrogen transfer. It was found that sulforaphane alone, without Fe-SOD, cannot scavenge superoxide radical anion in gas phase or aqueous media efficiently as the corresponding reaction barriers are very high. However, in the presence of Fe-SOD represented by the above-mentioned model, the scavenging reactions become barrierless, and so sulforaphane scavenges superoxide radical anion by converting it to hydrogen peroxide efficiently. Further, sulforaphane was found to scavenge hydrogen peroxide also very efficiently by converting it into water. Thus, the mechanism of action of sulforaphane as an excellent antioxidant has been unravelled. PMID:26020652

  6. Free-radical scavenging and mitochondrial antioxidant activities of Reishi-Ganoderma lucidum (Curt: Fr) P. Karst and Arogyapacha-Trichopus zeylanicus Gaertn extracts.

    PubMed

    Cherian, Elizabeth; Sudheesh, Narayana P; Janardhanan, Kainoor K; Patani, George

    2009-01-01

    Endogenous damage to mitochondrial DNA by free radicals is believed to be a major contributory factor to aging. The current study examined the effects of the extracts of two important anti-fatigue and rejuvenating medicinal herbs Ganoderma lucidum and Trichopus zeylanicus for their free-radical scavenging property and for their effects on liver mitochondrial antioxidant activity in aged mice. Both extracts were administrated orally to aged BALB/c mice at doses of 50 and 250 mg/kg body weight for 15 days. Super oxide dismutase (SOD) and catalase (CAT) activity and levels of reduced glutathione (GSH) and lipid peroxidation as equivalents of malondialdehyde (MDA) formed were determined. Groups of young mice and aged mice (more than 15 months old) were taken as controls. Both G. lucidum and T. zeylanicus extracts increased antioxidant status in liver mitochondria of aged mice compared with the aged control. Higher levels of GSH, increased activity of SOD and CAT, and decreased level of MDA in both treated groups compared with the controls were evident. Both extracts possessed significant 2,2-diphenyl-1-picrylhydrazil (DPPH), 2, 2'-azinobis (3-ethylbenzothiazolin-6-sulphonic acid) (ABTS) radical scavenging activities and ferric reducing antioxidant power (FRAP). The DPPH, ABTS, and FRAP activities were higher in G. lucidum extract than in T. zeylanicus. G. lucidum extract also showed superoxide and hydroxyl radical scavenging activities. T. zeylanicus had significantly higher lipid peroxidation inhibiting activity than G. lucidum. Thus, we conclude that the antioxidative effect of the G. lucidum extract was higher than that of T. zeylanicus. Our findings suggest a potential therapeutic efficacy of G. lucidum extract to protect against aging and to a certain extent against age-related degenerative diseases. PMID:20214017

  7. The free radical scavenging and antioxidant activities of pod and seed extract of Clitoria fairchildiana (Howard)- an underutilized legume.

    PubMed

    Annegowda, H V; Bhat, Rajeev; Tze, Liong Min; Karim, A A; Mansor, S M

    2013-06-01

    We evaluated the phenolic content and antioxidant capacities of pod and seed extracts (in methanol, ethanol, and water) of an underutilized legume, Clitoria fairchildiana (Howard). The antioxidant capacity of the extracts was determined using the ferric reducing antioxidant potential assay, and the free radical-scavenging capacity was evaluated using 2,2-diphenyl-1-picrylhydrazyl radical-scavenging and ABTS assays. In addition, the total flavonoids, flavonols, and tannin contents were also determined. Overall, the methanol extracts of the pod contained high concentration of phenolics and showed high antioxidant capacities compared to seed extracts. In addition, a positive correlation was found between total phenol and tannin versus antioxidant capacity. Results of the present study indicate pods and seeds of C. fairchildiana to possess rich amount of natural antioxidants, and can be further explored for their possible use as a natural additive in food or in pharmaceutical industries. PMID:24425949

  8. Synthesis and Biological Evaluation of 3-Benzylidene-4-chromanone Derivatives as Free Radical Scavengers and α-Glucosidase Inhibitors.

    PubMed

    Takao, Koichi; Yamashita, Marimo; Yashiro, Aruki; Sugita, Yoshiaki

    2016-01-01

    A series of 3-benzylidene-4-chromanone derivatives (3-20) were synthesized and the structure-activity relationships for antioxidant and α-glucosidase inhibitory activities were evaluated. Among synthesized compounds, compounds 5, 13, 18, which contain catechol moiety, showed the potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity (5: EC50 13 µM; 13: EC50 14 µM; 18: EC50 13 µM). The compounds 12, 14, 18 showed higher α-glucosidase inhibitory activity (12: IC50 15 µM; 14: IC50 25 µM; 18: IC50 28 µM). The compound 18 showed both of potent DPPH radical scavenging and α-glucosidase inhibitory activities. These data suggest that 3-benzylidene-4-chromanone derivatives, such as compound 18, may serve as the lead compound for the development of novel α-glucosidase inhibitors with antioxidant activity. PMID:27477661

  9. Preventive efficacy of hydroalcoholic extract of Cymbopogon citratus against radiation-induced DNA damage on V79 cells and free radical scavenging ability against radicals generated in vitro.

    PubMed

    Rao, B S S; Shanbhoge, R; Rao, B N; Adiga, S K; Upadhya, D; Aithal, B K; Kumar, M R S

    2009-04-01

    This study presents the findings of free radical scavenging and antigenotoxic effect of hydroalcoholic extract of Cymbopogon citratus (CCE). The CCE at a concentration of 60 microg/mL resulted in a significant scavenging ability of 2,2-diphenyl-2-picryl hydrazyl (DPPH; (85%), 2,2-azinobis (3-ethyl benzothiazoline-6-sulphonic acid) (ABTS; 77%), hydroxyl (70%), superoxide (76%), nitric oxide (78%) free radicals generated using in vitro and also a moderate anti-lipid peroxidative effect (57%). Further, the radiation-induced antigenotoxic potential of CCE was assessed in Chinese hamster lung fibroblast cells (V79) using micronucleus assay. The CCE resulted in a dose-dependent decrease in the yield of radiation-induced micronuclei, with a maximum effect at 125 microg/mL CCE for 1 h before 2 Gy of radiation. Similarly, there was a significant (P < 0.05-0.0001) decrease in percentage of micronuclei when V79 cells were treated with optimal dose of CCE (125 microg/mL) before exposure to different doses of gamma radiation, that is, 0.5-4 Gy, compared with radiation alone groups. The results of the micronucleus study indicated antigenotoxic effect demonstrating the radioprotective potential of CCE and, which may partly due to its and antioxidant capacity as it presented its ability to scavenge various free radicals in vitro and anti-lipid peroxidative potential. PMID:19734270

  10. Effects of Extraction and Processing Methods on Antioxidant Compound Contents and Radical Scavenging Activities of Laver (Porphyra tenera)

    PubMed Central

    Hwang, Eun-Sun; Thi, Nhuan Do

    2014-01-01

    Laver is one of the most consumed edible red algae seaweeds in the genus Porphyra. Laver is primarily prepared in the form of dried, roasted, and seasoned products. We investigated the total polyphenol and flavonoid contents of laver products, and evaluated the in vitro antioxidant properties of solvent extracts from commercially processed laver products. Significant differences in the concentration of phenolic compounds were found among differently processed laver. The total phenolic content for laver extracts ranged from 10.81 mg gallic acid equivalent (GAE)/g extract to 32.14 mg GAE/g extract, depending on extraction solvent and temperature. Laver extracts contained very few flavonoids (0.55 mg catechin equivalent/g extracts to 1.75 mg catechin equivalent/g extracts). 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), hydroxyl radical, and superoxide anion scavenging assays were used to determine the radical scavenging capacities of laver extracts. These assays revealed that the processing method and extraction condition affected the antioxidant potentials of laver. Antioxidant activity of dried laver, roasted laver, and seasoned laver increased in a concentration-dependent manner (100~1,000 μg/mL). The radical scavenging activities of 37°C and 100°C water extracts were lower than that of a 37°C 70% ethanol extract. The highest radical scavenging capacity was observed in the 37°C 70% ethanol extracts of dried laver, roasted laver, and seasoned laver. Overall, these results support that notion that laver contains bioactive compounds, such as polyphenols and flavonoids, which may have a positive effect on health. PMID:24772408

  11. Radical scavenging activities of Rio Red grapefruits and Sour orange fruit extracts in different in vitro model systems.

    PubMed

    Jayaprakasha, G K; Girennavar, Basavaraj; Patil, Bhimanagouda S

    2008-07-01

    Antioxidant fractions from two different citrus species such as Rio Red (Citrus paradise Macf.) and Sour orange (Citrus aurantium L.) were extracted with five different polar solvents using Soxhlet type extractor. The total phenolic content of the extracts was determined by Folin-Ciocalteu method. Ethyl acetate extract of Rio Red and Sour orange was found to contain maximum phenolics. The dried fractions were screened for their antioxidant activity potential using in vitro model systems such as 1,1-diphenyl-2-picryl hydrazyl (DPPH), phosphomolybdenum method and nitroblue tetrazolium (NBT) reduction at different concentrations. The methanol:water (80:20) fraction of Rio Red showed the highest radical scavenging activity 42.5%, 77.8% and 92.1% at 250, 500 and 1000 ppm, respectively, while methanol:water (80:20) fraction of Sour orange showed the lowest radical scavenging activity at all the tested concentrations. All citrus fractions showed good antioxidant capacity by the formation of phosphomolybdenum complex at 200 ppm. In addition, superoxide radical scavenging activity was assayed using non-enzymatic (NADH/phenaxine methosulfate) superoxide generating system. All the extracts showed variable superoxide radical scavenging activity. Moreover, methanol:water (80:20) extract of Rio Red and methanol extract of Sour orange exhibited marked reducing power in potassium ferricyanide reduction method. The data obtained using above in vitro models clearly establish the antioxidant potential of citrus fruit extracts. However, comprehensive studies need to be conducted to ascertain the in vivo bioavailability, safety and efficacy of such extracts in experimental animals. To the best of our knowledge, this is the first report on antioxidant activity of different polar extracts from Rio Red and Sour oranges. PMID:17935981

  12. Optimization of hydroxyl radical scavenging activity of exo-polysaccharides from Inonotus obliquus in submerged fermentation using response surface methodology.

    PubMed

    Chen, Hui; Xu, Xiangqun; Zhu, Yang

    2010-04-01

    The objectives of this study were to investigate the effect of fermentation medium on the hydroxyl radical scavenging activity of exo-polysaccharides from Inonotus obliquus by response surface methodology. A two-level fractional factorial design was used to evaluate the effect of different components of medium. Corn flour, peptone, and KH2PO4 were important factors significantly affecting hydroxyl radical scavenging activity. These selected variables were subsequently optimized using path of steepest ascent (descent), a central composite design, and response surface analysis. The optimal medium composition was (% w/v): corn flour 5.30, peptone 0.32, KH2PO4 0.26, MgSO4 0.02, and CaCl2 0.01. Under the optimal condition, the hydroxyl radical scavenging rate (49.4%) was much higher than that using either basal fermentation medium (10.2%) and single variable optimization of fermentation medium (35.5%). The main monosaccharides components of the RSM optimized polysaccharides are rhamnose, arabinose, xylose, mannose, glucose and galactose with molar proportion at 1.45%, 3.63%, 2.17%, 15.94%, 50.00%, and 26.81%. PMID:20467262

  13. Antioxidant Capacity and Radical Scavenging Effect of Polyphenol Rich Mallotus philippenensis Fruit Extract on Human Erythrocytes: An In Vitro Study

    PubMed Central

    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. PMID:25525615

  14. Prediction of Radical Scavenging Activities of Anthocyanins Applying Adaptive Neuro-Fuzzy Inference System (ANFIS) with Quantum Chemical Descriptors

    PubMed Central

    Jhin, Changho; Hwang, Keum Taek

    2014-01-01

    Radical scavenging activity of anthocyanins is well known, but only a few studies have been conducted by quantum chemical approach. The adaptive neuro-fuzzy inference system (ANFIS) is an effective technique for solving problems with uncertainty. The purpose of this study was to construct and evaluate quantitative structure-activity relationship (QSAR) models for predicting radical scavenging activities of anthocyanins with good prediction efficiency. ANFIS-applied QSAR models were developed by using quantum chemical descriptors of anthocyanins calculated by semi-empirical PM6 and PM7 methods. Electron affinity (A) and electronegativity (χ) of flavylium cation, and ionization potential (I) of quinoidal base were significantly correlated with radical scavenging activities of anthocyanins. These descriptors were used as independent variables for QSAR models. ANFIS models with two triangular-shaped input fuzzy functions for each independent variable were constructed and optimized by 100 learning epochs. The constructed models using descriptors calculated by both PM6 and PM7 had good prediction efficiency with Q-square of 0.82 and 0.86, respectively. PMID:25153627

  15. Prediction of radical scavenging activities of anthocyanins applying adaptive neuro-fuzzy inference system (ANFIS) with quantum chemical descriptors.

    PubMed

    Jhin, Changho; Hwang, Keum Taek

    2014-01-01

    Radical scavenging activity of anthocyanins is well known, but only a few studies have been conducted by quantum chemical approach. The adaptive neuro-fuzzy inference system (ANFIS) is an effective technique for solving problems with uncertainty. The purpose of this study was to construct and evaluate quantitative structure-activity relationship (QSAR) models for predicting radical scavenging activities of anthocyanins with good prediction efficiency. ANFIS-applied QSAR models were developed by using quantum chemical descriptors of anthocyanins calculated by semi-empirical PM6 and PM7 methods. Electron affinity (A) and electronegativity (χ) of flavylium cation, and ionization potential (I) of quinoidal base were significantly correlated with radical scavenging activities of anthocyanins. These descriptors were used as independent variables for QSAR models. ANFIS models with two triangular-shaped input fuzzy functions for each independent variable were constructed and optimized by 100 learning epochs. The constructed models using descriptors calculated by both PM6 and PM7 had good prediction efficiency with Q-square of 0.82 and 0.86, respectively. PMID:25153627

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

    PubMed Central

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

    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 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. PMID:24754012

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

    PubMed

    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. PMID:25525615

  18. Dry and ripe fruit of Aegle marmelos. L: A potent source of antioxidant, lipoxygenase inhibitors and free radical scavenger.

    PubMed

    Rahman, Atiqur; Imran, Hina; Iqbal, Lubna; STaqvi, Syed Intasar Hussain; Fatima, Nudrat; Yaqeen, Zahra

    2016-07-01

    The antioxidant, lipoxygenase inhibitory activities and free radical scavenging capacity of the crude extract, aqueous and some organic fractions of dry and ripe fruit of Aeglemarmelos. L were studied to understand the protective and therapeutic role for the use of the fruit as a remedy in different ailments. All the tested fractions and extracts showed to possess significant antioxidant, free radical scavenging capacity and lipoxygenase inhibitory potential. However, chloroform and aqueous fractions showed significant ability to quench radicals, to reduce ferric chloride and to inhibit soyabean lipoxygenase. Their antioxidant and lipoxygenase inhibition was estimated by IC50 values, for antioxidant ranging from 88-65% activity at concentration of 5-0.15μ/mL and similarly for lipoxygenase inhibition ranging from 89-69% at various concentrations of 5-0.15μ/mL, in chloroform and aqueous fractions respectively. The scavenger molecules in the dry and ripe fruit of A. marmelos may attribute to therapeutic and protective effect during different progressive stages of ailments. PMID:27393425

  19. Extracts and constituents of Rubus chingii with 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity.

    PubMed

    Ding, Hsiou-Yu

    2011-01-01

    The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of the fruits of Rubus chingii was studied in vitro. Ethanolic extract, ethyl acetate and n-butanol fractions from dried R. chingii fruits revealed strong DPPH free radical scavenging activity with IC(50) values of 17.9, 3.4 and 4.0 μg/mL, respectively. The ethyl acetate and n-butanol fractions were further purified by a combination of silica gel chromatography, Lobar RP-8 chromatography, and high-pressure liquid chromatography (HPLC). Nine compounds were isolated, where methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl)-acetate (2), vanillic acid (5), kaempferol (7), and tiliroside (9) showed stronger DPPH free radical scavenging activity than that of ascorbic acid (131.8 μM) with IC(50) values of 45.2, 34.9, 78.5, and 13.7 μM, respectively. In addition, rubusine (1) is a new compound discovered in the present study and methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl)-acetate (2), methyl dioxindole-3-acetate (3), and 2-oxo-1,2-dihydroquinoline-4-carboxylic acid (4) were isolated from the fruits for the first time. PMID:21747716

  20. Free radical scavenging capacity, anticandicidal effect of bioactive compounds from Sida Cordifolia L., in combination with nystatin and clotrimazole and their effect on specific immune response in rats

    PubMed Central

    2012-01-01

    Background Infectious diseases caused by fungi are still a major threat to public health, despite numerous efforts by researchers. Use of ethnopharmacological knowledge is one attractive way to reduce empiricism and enhance the probability of success in new drug-finding efforts. In this work, the total alkaloid compounds (AC) from Sida cordifolia L. (Malvaceae) have been investigated for their free radical scavenging capacity, antifungal and immunostimulatory properties. Method The antifungal activity was investigated against five candida strains using the microplate dilution method and the Fractional Inhibitory Concentration Index (FICI) of compounds was evaluated. The antioxidant activity of the samples was evaluate using three separate methods, at last, the immunostimulatory effect on immunosuppressed wistar rats was performed. Results As for the antifungal activity, result varied according to microorganism. The results obtained in this antifungal activity were interesting and indicated a synergistic effect between alkaloid compounds and the antifungal references such as Nystatin and Clotrimazole. Antioxidant capacity noticed that the reduction capacity of DPPH radicals obtained the best result comparatively to the others methods of free radical scavenging. Our results showed a low immunostimulatory effect and this result could be explained by the lack of biologically active antioxidants such as polyphenol compounds lowly contained in the alkaloid compounds. Conclusion The results of this study showed that alkaloid compounds in combination with antifungal references (Nystatin and Clotrimazole) exhibited antimicrobial effects against candida strains tested. The results supported the utilization of these plants in infectious diseases particularly in treatment of candida infections. PMID:23268761

  1. Radiation protection of in vitro mammalian cells: effects of hydroxyl radical scavengers on the slopes and shoulders of survival curves

    SciTech Connect

    Ewing, D.; Walton, H.L. )

    1991-05-01

    We have tested several chemical compounds, characterized and widely used as hydroxyl radical (.OH) scavengers, for their effects on the radiation sensitivity of Chinese hamster V79 cells irradiated in air or nitrogen. Our purpose is to reexamine the proposed relationship between the level of protection and the rates at which the scavengers react with .OH. We found that the additives can have two apparently independent effects on the shape of survival curves: a reduction in sensitivity (i.e., 'protection,' a decrease in the value of k) and an increase in the size of the shoulder of the survival curve (an increase in the value of Dq). We measured intracellular scavenger concentrations, and, using these values in our analysis, we found that neither of the two effects is correlated with the rates at which the scavengers react with .OH. Although these results could mean that .OH do not cause lethal damage, the interpretation we believe most probably correct is that these scavengers protect in multiple ways. The protection would occur in addition to or instead of simple .OH removal.

  2. The influence of radical transfer and scavenger materials in various concentrations on the gamma radiolysis of phenol

    NASA Astrophysics Data System (ADS)

    Kozmér, Zsuzsanna; Takács, Erzsébet; Wojnárovits, László; Alapi, Tünde; Hernádi, Klára; Dombi, András

    2016-07-01

    The influence of a radical scavenger (tert-butanol (t-BuOH)) and two radical transfer materials (formic acid (HCOOH) and formate anion (HCOO-)) on the radical set during radiolysis of a simple model compound, phenol (PhOH, 1.0×10-4 mol L-1) is discussed in this study. PhOH solutions were irradiated with γ-rays, in the presence of 1.0×10-3, 5.0×10-2 and 5.0×10-1 mol L-1t-BuOH, HCOOH or HCOONa under deoxygenated and O2-saturated reaction conditions. The rate of transformation of PhOH increased significantly in the presence of dissolved O2. The radical transfer or scavenger materials used reduced the rates of transformation of PhOH in O2-saturated solutions to a similar degree. The simultaneous presence of O2 and the organic additives in excess proportionally to PhOH results in the conversion of the radical set to less reactive intermediates (t-•OOBuOH, HO2• or O2•-), which made minor contribution to the transformation of PhOH. Under oxygenated conditions, t-BuOH and HCOOH in low concentrations slightly promoted the degradation, as opposed to HCOO- which reduced it. However, using higher additive concentrations, their competitive reactions for the primary intermediates came into prominence, thus they reduced the efficiency of PhOH decomposition. HO2• and O2•-, and also the carbon-centred radicals formed (order of their reactivity t-•BuOH>•COOH> CO2•-) have only a minor contribution to the degradation of PhOH, and the reactions of •OH+PhOH and eaq-+PhOH are the significant processes.

  3. Free radical scavengers from Cymbopogon citratus (DC.) stapf plants cultivated in bioreactors by the temporary immersion (TIS) principle.

    PubMed

    Tapia, Alejandro; Cheel, José; Theoduloz, Cristina; Rodríguez, Jaime; Schmeda-Hirschmann, Guillermo; Gerth, Andre; Wilken, Dirk; Jordan, Miguel; Jiménez-González, Elio; Gomez-Kosky, Rafael; Mendoza, Elisa Quiala

    2007-01-01

    The biomass production of Cymbopogon citratus shoots cultivated in bioreactors according to the temporary immersion (TIS) principle was assessed under different growth conditions. The effect of gassing with CO2-enriched air, reduced immersion frequency, vessel size and culture time on total phenolic and flavonoid content and free radical scavenging effect of the methanolic extracts was measured. From the TIS-culture of C. citratus, seven compounds were isolated and identified as caffeic acid (1), chlorogenic acid (2), neochlorogenic acid (3), p-hydroxybenzoic acid (4), p-hydroxybenzoic acid 3-O-beta-D-glucoside (5), glutamic acid (6) and luteolin 6-C-fucopyranoside (7). The occurrence of compounds 1-7 and their variability in C. citratus grown under different TIS conditions was determined by HPLC. The free radical scavenging effect of the methanolic extract and compounds was measured by the discoloration of the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH). The main metabolites in 6- and 8-week-old cultures, both in 5 and 10 1 vessels, were chlorogenic acid (2) (100-113 mg%) and neochlorogenic acid (3) (80-119 mg%), while in the cultures with CO2-enriched air and reduced immersion frequency the main compound detected in the extracts was glutamic acid (6) (400 and 670 mg% for the green and white biomass and 619 and 630 mg% for the green and white biomass, respectively). The most active compounds, as free radical scavengers, in the DPPH discoloration assay were caffeic acid (1), chlorogenic acid (2), neochlorogenic acid (3) and the flavonoid luteolin 6-C-fucopyranoside (7). PMID:17708453

  4. Phytochemical screening and free radical scavenging activity of Citrullus colocynthis seeds extracts

    PubMed Central

    Benariba, Nabila; Djaziri, Rabeh; Bellakhdar, Wafaa; Belkacem, Nacera; Kadiata, Marcel; Malaisse, Willy J.; Sener, Abdullah

    2013-01-01

    Objective To study the phytochemical screening of different extracts from Citrullus colocynthis (C. colocynthis ) seeds extracts and to assess their antioxidant activity on the DPPH free radical scavenging. Methods Phytochemical screening, total content of polyphenols and flavonoids of C. colocynthis seeds extracts, including a crude aqueous extract (E1), a defatted aqueous extract (E2), a hydromethanolic extract (HM), an ethyl acetate extract (EA) and a n-butanol extract (n-B) was carried out according to the standard methods and to assess their corresponding effect on the antioxidant activity of this plant. Results None of these extracts contained detectable amount of alkaloid, quinone, antraquinone, or reducing sugar. Catechic tannins and flavonoids were abundant in E1, HM and EA, whilst terpenoids were abundantly present in E1 and n-B but only weekly in HM. Coumarins were found in E2, EA and n-B. Polyphenols, expressed as gallic acid equivalent, amounted, per 100 g plant matter, to 329, 1002 and 150 mg in EA, HM an E1 respectively. Flavonoids, expressed as catechin equivalent, amounted, per 100 g plant matter to 620, 241 and 94 mg in EA, HM and E1 respectively. Comparable values were found in n-B and E1, with lower values in E2. Quercetin, myricetin and gallic acid were found in the EA and HM extracts by thin layer chromatography, The antioxidative effect of these extracts yielded, when tested at a concentration of 2 000 µg/mL in a 1,1-diphenyl-2-picrylhydrazyl assay, a reducing percentage of 88.8% with EA, 74.5% with HM and 66.2% with E1, and corresponding IC50 of 350, 580 and 500 µg/mL as compared to 1.1 µg/mL for ascorbic acid. Conclusions These qualitative and quantitative analytical data document the presence in C. colocynthis extracts of such chemical compounds as flavonoids responsible for the antioxidant activity, as well as other biological activities of this plant. PMID:23570014

  5. High-molar-mass hyaluronan behavior during testing its radical scavenging capacity in organic and aqueous media: effects of the presence of manganese(II) ions.

    PubMed

    Rapta, Peter; Valachová, Katarína; Gemeiner, Peter; Soltés, Ladislav

    2009-02-01

    This study compares the radical scavenging capacity of high-molar-mass hyaluronan (HA) using standardized methods applying 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and 2,2'-azinobis[3-ethylbenzthiazoline sulfonate] (ABTS) radical cations as oxidants. Additionally, spin-trapping technique combined with electron paramagnetic resonance (EPR) was used to evaluate the ability of HA to scavenge reactive radicals. The thermal decomposition of K2S2O8 in pure H2O or in a H2O/dimethyl sulfoxide (DMSO) mixture at 333 K was used as a source of reactive paramagnetic species. We found that HA does not exhibit radical-scavenging activity when DPPH radicals or ABTS(.+) radical cations are used as oxidant, but that HA is an effective radical scavenger at low concentrations, if the oxidation reactions are initiated by the decomposition of K2S2O8. At higher HA concentrations, a more complex behavior and prooxidant HA action was observed. The influence of Mn(II) ions on the reaction mechanisms of radical generation and termination in the K2S2O8/H2O/DMSO system in the presence of HA was studied in detail. PMID:19235158

  6. Synthesis, crystal structure, ABTS radical-scavenging activity, antimicrobial and docking studies of some novel quinoline derivatives

    NASA Astrophysics Data System (ADS)

    Tabassum, Sumaiya; Suresha Kumara, T. H.; Jasinski, Jerry P.; Millikan, Sean P.; Yathirajan, H. S.; Sujan Ganapathy, P. S.; Sowmya, H. B. V.; More, Sunil S.; Nagendrappa, Gopalpur; Kaur, Manpreet; Jose, Gilish

    2014-07-01

    In this study, a series of nine novel 2-chloroquinolin-3-yl ester derivatives have been synthesized via a two-step protocol from 2-chloroquinoline-3-carbaldehyde. The structures of all these compounds were confirmed by spectral data. The single crystal X-ray structure of two derivatives, (2-chloroquinolin-3-yl)methyl acetate [6a] and (2-chloro-6-methylquinolin-3-yl)methyl acetate [6e] have also been determined. The synthesized compounds were further evaluated for their ABTS radical-scavenging activity and antimicrobial activities. Amongst all the tested compounds, 6a exhibited maximum scavenging activity with ABTS. Concerning antibacterial and antifungal activities, compound (2-chloro-6-methoxyquinolin-3-yl)methyl 2,4-dichlorobenzoate [6i] was found to be the most active in the series against B. subtilis, S. aureus, E. coli, K. pneumonia, C. albicans and A. niger species. The structure-antimicrobial activity relationship of these derivatives were studied using Autodock.

  7. Croton cajucara Benth. leaf extract scavenges the stable free radical DPPH and protects against oxidative stress induced by paraquat.

    PubMed

    Tieppo, Marcelo; Porawski, Marilene; Salvador, Mirian; Moreira, Andrea Janz; Collado, Pilar Sanzchez; González-Gallego, Javier; Marroni, Norma Possa

    2006-01-01

    Antioxidant effects of extracts from Croton cajucara BENTH. leaves was investigated in different in vitro and in vivo models. Extracts showed inhibitory radical scavenging activity against the stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) (75%, 43% and 25% of the standard trolox at 1, 10 and 100 mg/ml, respectively; IC50 218 mg/ml). Percentage survival of Saccharomyces cerevisiae cells treated with 10 mM paraquat increased by 21% and 55%, when 1 mg/ml and 10 mg/ml concentrations of the extract, respectively, were added. The cytosolic concentration of TBARS increased in animals treated with paraquat (+283%), while values did not significantly differ from the controls in rats additionally receiving the leaf extract. Paraquat administration also induced a significant increase in hydroperoxide-initiated chemiluminiscence (+76%), that was partially prevented by the leaf extract (+31%). Liver SOD activity was a 158% higher in animals receiving paraquat as compared to the controls. This effect was abolished by administration of the leaf extract. Paraquat administration did not significantly modify the activity of GPx or catalase. Croton cajucara extract increased GPx and catalase activities in paraquat treated-animals by 342% and 70%, respectively. Our results confirm that Croton cajucara leaf extract present radical scavenging activity and reduce oxidative stress induced by paraquat, suggesting the beneficial use as a potential source of antioxidant agents of natural origin. PMID:16394531

  8. Effect of deodorization of camelina (Camelina sativa) oil on its phenolic content and the radical scavenging effectiveness of its extracts.

    PubMed

    Hrastar, Robert; Terpinc, Petra; Košir, Iztok Jože; Abramovič, Helena

    2013-08-28

    The influence of deodorization parameters (temperature (T), steam flow (S), time (t)) on the phenolic content and radical scavenging effectiveness (RSE) of methanolic extracts of camelina oil was investigated and analyzed by response-surface methodology (RSM). The phenolic content can be considered to be a linear function of all three parameters. A positive linear relationship between the content of phenolic compounds in deodorized oils and RSE was observed. Deodorization at 210 °C with a steam flow of 3 mL/h for 90 min resulted in the best preservation of phenolics, amounting to 29.9 mg/kg. The lowest reduction from RSE of 12.4 μM Trolox equivalents (TE)/g oil for the crude oil was observed for oil treated at 195 °C and 18 mL/h for 60 min with RSE of 10.1 μM TE/g oil. The lack of correlation between RSE or total phenolic content and oxidative stability (OS) of the deodorized oils suggests that antioxidants in scavenging radicals react by different mechanisms, depending on radical type and reaction medium. PMID:23927732

  9. Lactoferrin Directly Scavenges Hydroxyl Radicals and Undergoes Oxidative Self-Degradation: A Possible Role in Protection against Oxidative DNA Damage

    PubMed Central

    Ogasawara, Yuki; Imase, Megumi; Oda, Hirotsugu; Wakabayashi, Hiroyuki; Ishii, Kazuyuki

    2014-01-01

    In this study, we examined the protective effect of lactoferrin against DNA damage induced by various hydroxyl radical generation systems. Lactoferrin (LF) was examined with regard to its potential role as a scavenger against radical oxygen species using bovine milk LF. Native LF, iron-saturated LF (holo-LF), and apolactoferrin (apo-LF) effectively suppressed strand breaks in plasmid DNA due to hydroxyl radicals produced by the Fenton reaction. In addition, both native LF and holo-LF clearly protected calf thymus DNA from fragmentation due to ultraviolet irradiation in the presence of H2O2. We also demonstrated a protective effect of all three LF molecules against 8-hydroxydeoxyguanosine (8-OHdG) formation in calf thymus DNA following ultraviolet (UV) irradiation with H2O2. Our results clearly indicate that native LF has reactive oxygen species-scavenging ability, independent of its nature as a masking component for transient metals. We also demonstrated that the protective effect of LF against oxidative DNA damage is due to degradation of LF itself, which is more susceptible to degradation than other bovine milk proteins. PMID:24424315

  10. A joint application of spectroscopic, electrochemical and theoretical approaches in evaluation of the radical scavenging activity of 3-OH flavones and their iron complexes towards different radical species.

    PubMed

    Dimitrić Marković, Jasmina M; Marković, Zoran S; Pašti, Igor A; Brdarić, Tanja P; Popović-Bijelić, Ana; Mojović, Miloš

    2012-06-28

    Combined spectroscopic (UV/visible, MS and EPR), electrochemical (CV) and theoretical approaches were used to evaluate the relevant interactions of morin and quercetin, as well as their respective iron(III) complexes with DPPH, tempone, hydroxyl and superoxide radicals. The results on iron complexation specify the stoichiometry and the relevant structural forms entering the chelation of the molecules. The spectroscopic DPPH assay shows better antioxidant activity of quercetin and its iron complex both in terms of EC(50) values and stoichiometry. The results of 2-deoxyribose degradation suggest that antioxidant activities of morin and quercetin may originate from their combined effect of iron chelation and radical scavenging. The distinctive difference in the EPR spectra of morin and quercetin radicals suggests different positions of the radical centers which may account for different sequences of their activities towards investigated radicals. Activity ranking of quercetin and morin, established by cyclic voltammetry, confirms their activity sequence obtained by EPR results and is also in agreement with the results of conformational analysis. The equilibrium geometries, optimized with the M052X functionals and 6-311G(d,p) basis set, predict structural modifications between the ligand molecules in the free state and in the complex structures. The arguments gained through experimental results can also be rationalized in terms of overall molecular geometry and structural features governing antioxidant behavior i.e. substitution pattern of the ring B. PMID:22576733

  11. Cytotoxic, radical scavenging and antimicrobial activities of sesquiterpenoids from the Tahitian liverwort Mastigophora diclados (Brid.) Nees (Mastigophoraceae).

    PubMed

    Komala, Ismiarni; Ito, Takuya; Nagashima, Fumihiro; Yagi, Yasuyuki; Asakawa, Yoshinori

    2010-10-01

    A drimane, (+)-drimenol (1), five known herbertanes, (-)-alpha-herbertenol (2), (-)-herbertenediol (3), mastigophorene A (4), (-)-mastigophorene C (5) and (-)-mastigophorene D (6), a pimarane, (-)-ent-pimara-8(14),15-dien-19-oic acid (7), and two eudesmanolides, (-)-diplophyllolide A (8) and (-)-diplophyllin (9) were isolated from the Tahitian Mastigophora diclados (Brid.) Nees. Herbertane sesquiterpenes (2, 3, 5 and 6) showed cytotoxicity against HL-60 and KB cell lines, radical scavenging activity and antimicrobial activity against Bacillus subtilis. (-)-Diplophyllolide A (8) also exhibited cytotoxicity against HL-60 and KB cell lines. PMID:20458547

  12. Radical scavenging and reducing ability of tilapia (Oreochromis niloticus) protein hydrolysates.

    PubMed

    Raghavan, Sivakumar; Kristinsson, Hordur G; Leeuwenburgh, Christiaan

    2008-11-12

    Enzymatically hydrolyzed fish protein hydrolysates could be used as a source of antioxidative nutraceuticals. In our current work, we have investigated alkali-solubilized tilapia ( Oreochromis niloticus) protein hydrolysates for their ability to scavenge reactive oxygen species (ROS) and for their reducing power. Tilapia protein isolate was prepared by an alkaline solubilization technique and used as a substrate for enzyme hydrolysis. Cryotin, protease A 'Amano' 2, protease N 'Amano', Neutrase and Flavourzyme, were used separately to determine their effectiveness in hydrolyzing tilapia protein isolate. ROS scavenging ability was quantified using an isoluminol enhanced chemiluminescent assay in the presence of a) hydrogen peroxide or b) mononuclear cells isolated from human blood. Ferric reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) of the hydrolysates using 2, 2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) or 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), were also investigated. Results showed that, in general, the TEAC, FRAP values and ROS scavenging ability of the hydrolysates increased with an increase in the degree of hydrolysis. Among the different hydrolysates, those prepared using Cryotin were most effective and Amano A2 hydrolysates were least effective in scavenging ABTS*(+) and ROS generated by hydrogen peroxide. However, FRAP assay showed that hydrolysates prepared using Flavourzyme were most effective, and Amano N and Neutrase hydrolysates were least effective in reducing ferric ions. No significant difference was observed among the hydrolysates produced with different enzymes in their ability to scavenge ROS generated by phorbol myristate acetate stimulated mononuclear cells. These results shed light on the in vitro ROS scavenging ability of alkali solubilized tilapia protein hydrolysates, as well as potential nutraceutical use of these hydrolysates. PMID:18828605

  13. Changes in oxygen consumption induced by t-butyl hydroperoxide in perfused rat liver. Effect of free-radical scavengers.

    PubMed Central

    Videla, L A; Villena, M I; Donoso, G; Giulivi, C; Boveris, A

    1984-01-01

    The addition of t-butyl hydroperoxide to perfused rat liver elicited a biphasic effect on hepatic respiration. A rapid fall in liver oxygen consumption was initially observed, followed by a recovery phase leading to respiratory rates higher than the initial steady-state values of oxygen uptake. This overshoot in hepatic oxygen uptake was abolished by free-radical scavengers such as (+)-cyanidanol-3 or butylated hydroxyanisole at concentrations that did not alter mitochondrial respiration. (+)-Cyanidanol-3 was also able to facilitate the recovery of respiration, the diminution in the calculated rate of hydroperoxide utilization and the decrease in liver GSH content produced by two consecutive pulses of t-butyl hydroperoxide. It is suggested that the t-butyl hydroperoxide-induced overshoot in liver respiration is related to increased utilization of oxygen for lipid peroxidation as a consequence of free radicals produced in the scission of the hydroperoxide by cellular haemoproteins. PMID:6508746

  14. Evaluation of Abelmoschus moschatus extracts for antioxidant, free radical scavenging, antimicrobial and antiproliferative activities using in vitro assays

    PubMed Central

    2011-01-01

    Background Abelmoschus moschatus Medik. leaves and seeds are considered as valuable traditional medicine. The aromatic seeds of this plant are aphrodisiac, ophthalmic, cardio tonic, antispasmodic and used in the treatment of intestinal complaints and check queasiness. To give a scientific basis for traditional usage of this medicinal plant, the seed and leaf extracts were evaluated for their antioxidant, free radical scavenging, antimicrobial and antiproliferative activities. Methods In this study, antioxidant, antimicrobial and antiproliferative activities of A. moschatus extracts were evaluated in a series of in vitro assay involving free radicals, reactive oxygen species and their IC50 values were also determined. The antioxidant activities of the seed and leaf extracts of A. moschatus were determined by total antioxidant, DPPH, and ferrous reducing antioxidant property (FRAP) methods. In addition, the antiproliferative activity was also evaluated using colorectal adenocarcinoma and retinoblastoma human cancer cell lines. Moreover, six bacterial reference strains, two gram-positive (Bacillus subtilis and Staphylococcus aureus), four gram-negative (Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris and Salmonella enterica paratyphi) and one fungal strain (Candida albicans) were used to evaluate its antimicrobial activity. Results The results from this study showed that the antioxidant activities of A. moschatus as determined by the total phenol, flavonoids, total antioxidant and FRAP methods were higher in leaf than that of the seed extracts. On the other hand, the aqueous overnight seed extract (AMS-I) has shown significant radical scavenging activity as in 1, 1- Diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide, hydroxyl radical, superoxide and lipid peroxidation as compared to other seed and leaf extracts. The AMS-I and AML-IV have shown activity against six and seven microorganisms respectively. Simulteneously, AMS-IV and AML-IV have demonstrated

  15. Bioactive lipids, radical scavenging potential, and antimicrobial properties of cold pressed clove (Syzygium aromaticum) oil.

    PubMed

    Assiri, Adel Mohamad Ali; Hassanien, Mohamed F R

    2013-11-01

    Health promoting cold pressed oils may improve human health and prevent certain diseases. It is hard to find any research concerning the composition and functional properties of cold pressed clove (Syzygium aromaticum) oil (CO). Cold pressed CO was evaluated for its lipid classes, fatty acid profiles, and tocol contents. In addition, antiradical and antimicrobial properties of CO were evaluated. The amounts of neutral lipids in CO was the highest (∼94.7% of total lipids), followed by glycolipids and phospholipids. The main fatty acids in CO were linoleic and oleic, which comprise together ∼80% of total fatty acids. Stearic and palmitic acids were the main saturated fatty acids. α- and γ-tocopherols and δ-tocotrienol were the main detected tocols. CO had higher antiradical action against DPPH• and galvinoxyl radicals than virgin olive oil. The results of antimicrobial properties revealed that CO inhibited the growth of all tested microorganisms. CO had a drastic effect on the biosynthesis of proteins and lipids in cells of Bacillus subtilis. In consideration of potential utilization, detailed knowledge on the composition and functional properties of CO is of major importance. PMID:24180551

  16. Biphenyl compounds are hydroxyl radical scavengers: their effective inhibition for UV-induced mutation in Salmonella typhimurium TA102.

    PubMed

    Fujita, S; Taira, J

    1994-09-01

    In our previous study, we found several hydroxylated biphenyl compounds have a great scavenging effect for hydroxyl radicals (.OH). In this study, to elucidate the relationship between generation of the .OH and photo-mutagenesis, six biphenyl compounds such as dehydrodieugenol, dehydrodivanillyl alcohol, dehydrodidihydroeugenol, dehydrodicreosol, magnolol and honokiol, respectively, were examined for their ability to inhibit UV-induced mutation in Salmonella typhimurium TA102. The relative mutagenic activities (RMA, %) indicated the mutation frequency of treated cells divided by the mutation frequency of control cells times 100%. The RMA (%) are as follows: 28 +/- 1, 31 +/- 1, 33 +/- 1, 41 +/- 2, 62 +/- 1, and 62 +/- 4 at concentrations of 5 micrograms per plate for dehydrodieugenol, dehydrodivanillyl alcohol, dehydrodidihydroeugenol, dehydrodicreosol, magnolol, and honokiol, respectively. These values indicate that low concentrations of these biphenyl compounds effectively suppress UV-induced mutagenesis. Also, these compounds acted as effective antimutagens in a dose-dependent manner (0.00005-5 micrograms per plate). These compounds are effective .OH scavengers. Consequently, the results obtained above suggest that these compounds could inhibit against UV-induced mutations by scavenging of .OH generated by UV irradiation. The results also suggest that .OH are associated with UV-induced mutation in Salmonella typhimurium TA102. PMID:7982632

  17. Radical scavenging and cytochrome P450 3A4 inhibitory activity of bergaptol and geranylcoumarin from grapefruit.

    PubMed

    Girennavar, Basavaraj; Jayaprakasha, G K; Jadegoud, Y; Nagana Gowda, G A; Patil, Bhimanagouda S

    2007-06-01

    Grapefruit juice has been shown to increase the oral bioavailability of several clinically important drugs by inhibiting first pass metabolism. Several compounds in grapefruit juice have shown different biological activities. Unique among them are furocoumarins with potent inhibitory activity against cytochrome P450 enzymes. In the present study, two bioactive compounds were isolated from grapefruit juice and grapefruit peel oil. The purity of the isolated compounds has been analyzed by HPLC. Structures of the compounds were elucidated by extensive NMR and mass spectral studies and identified as bergaptol and geranylcoumarin. The isolated compounds were tested for their radical scavenging activity using 2,2'-azobis (3-ethylbenz-thiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazil (DPPH) methods at different concentrations. Bergaptol showed very good radical scavenging activity at all the tested concentrations. Furthermore, these compounds were evaluated for their inhibitory activity against CYP3A4 enzyme. Bergaptol and geranylcoumarin were found to be potent inhibitors of debenzylation activity of CYP3A4 enzyme with an IC(50) value of 24.92 and 42.93 microM, respectively. PMID:17400460

  18. Development of an in Silico Model of DPPH• Free Radical Scavenging Capacity: Prediction of Antioxidant Activity of Coumarin Type Compounds.

    PubMed

    Goya Jorge, Elizabeth; Rayar, Anita Maria; Barigye, Stephen J; Jorge Rodríguez, María Elisa; Sylla-Iyarreta Veitía, Maité

    2016-01-01

    A quantitative structure-activity relationship (QSAR) study of the 2,2-diphenyl-l-picrylhydrazyl (DPPH•) radical scavenging ability of 1373 chemical compounds, using DRAGON molecular descriptors (MD) and the neural network technique, a technique based on the multilayer multilayer perceptron (MLP), was developed. The built model demonstrated a satisfactory performance for the training ( R 2 = 0.713 ) and test set ( Q ext 2 = 0.654 ) , respectively. To gain greater insight on the relevance of the MD contained in the MLP model, sensitivity and principal component analyses were performed. Moreover, structural and mechanistic interpretation was carried out to comprehend the relationship of the variables in the model with the modeled property. The constructed MLP model was employed to predict the radical scavenging ability for a group of coumarin-type compounds. Finally, in order to validate the model's predictions, an in vitro assay for one of the compounds (4-hydroxycoumarin) was performed, showing a satisfactory proximity between the experimental and predicted pIC50 values. PMID:27338348

  19. Development of an in Silico Model of DPPH• Free Radical Scavenging Capacity: Prediction of Antioxidant Activity of Coumarin Type Compounds

    PubMed Central

    Goya Jorge, Elizabeth; Rayar, Anita Maria; Barigye, Stephen J.; Jorge Rodríguez, María Elisa; Sylla-Iyarreta Veitía, Maité

    2016-01-01

    A quantitative structure-activity relationship (QSAR) study of the 2,2-diphenyl-l-picrylhydrazyl (DPPH•) radical scavenging ability of 1373 chemical compounds, using DRAGON molecular descriptors (MD) and the neural network technique, a technique based on the multilayer multilayer perceptron (MLP), was developed. The built model demonstrated a satisfactory performance for the training (R2=0.713) and test set (Qext2=0.654), respectively. To gain greater insight on the relevance of the MD contained in the MLP model, sensitivity and principal component analyses were performed. Moreover, structural and mechanistic interpretation was carried out to comprehend the relationship of the variables in the model with the modeled property. The constructed MLP model was employed to predict the radical scavenging ability for a group of coumarin-type compounds. Finally, in order to validate the model’s predictions, an in vitro assay for one of the compounds (4-hydroxycoumarin) was performed, showing a satisfactory proximity between the experimental and predicted pIC50 values. PMID:27338348

  20. Chemical composition, anti-inflammatory, molluscicidal and free-radical scavenging activities of the leaves of Ficus radicans 'Variegata' (Moraceae).

    PubMed

    Naressi, Maria Augusta; Ribeiro, Marcos Alessandro dos Santos; Bersani-Amado, Ciomar Aparecida; Zamuner, Maria Lucilia M; Costa, Willian Ferreira da; Tanaka, Clara M Abe; Sarragiotto, Maria Helena

    2012-01-01

    The methanol crude extract of the leaves of Ficus radicans Roxb. 'Variegata' (Moraceae) and the n-hexane, ethyl acetate and aqueous methanol fractions resulting from its fractionation were evaluated for their anti-inflammatory, molluscicidal and free-radical scavenging activities. The crude extract and fractions exhibited significant inhibition of inflammation in both croton oil (CO)-induced ear oedema in mice (p<0.001) and carrageenan-induced rat paw oedema models (p<0.01). The molluscicidal assay against Biomphalaria glabrata showed a weak activity for the n-hexane fraction (DL(50)= 400 µg mL(-1)). A moderated 1,1-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging activity was observed for the ethyl acetate fraction (IC(50)= 66.2 µg mL(-1)). Fractionation of the extracts through chromatographic methods afforded the coumarins 7-methoxycoumarin, 7-hydroxy-6-methoxycoumarin and methoxy-3,4-dihydrocoumarin, the steroids β-sitosterol and β-sitosterol 3-O-β-glucopyranoside, as well as a cinnamic acid derivative and a flavonoid identified as trans-4-methoxy-2-β-D-glucopyranosyloxy cinnamic acid and quercetin 3-O-β-D-xylopyranosyl-(1 → 2)-α-L-rhamnopyranoside, respectively. The compounds were identified on the basis of their NMR spectral data and comparison with those previously reported in the literature. PMID:21424983

  1. Influence of fatty acid on lipase-catalyzed synthesis of ascorbyl esters and their free radical scavenging capacity.

    PubMed

    Stojanović, Marija; Carević, Milica; Mihailović, Mladen; Veličković, Dušan; Dimitrijević, Aleksandra; Milosavić, Nenad; Bezbradica, Dejan

    2015-01-01

    Fatty acid (FA) ascorbyl esters are recently emerging food, cosmetic, and pharmaceutical additives, which can be prepared in an eco-friendly way by using lipases as catalysts. Because they are amphiphilic molecules, which possess high free radical scavenging capacity, they can be applied as liposoluble antioxidants as well as emulsifiers and biosurfactants. In this study, the influence of a wide range of acyl donors on ester yield in lipase-catalyzed synthesis and ester antioxidant activity was examined. Among saturated acyl donors, higher yields and antioxidant activities of esters were achieved when short-chain FAs were used. Oleic acid gave the highest yield overall and its ester exhibited a high antioxidant activity. Optimization of experimental factors showed that the highest conversion (60.5%) in acetone was achieved with 5 g L(-1) of lipase, 50 mM of vitamin C, 10-fold molar excess of oleic acid, and 0.7 mL L(-1) of initial water. Obtained results showed that even short- and medium-chain ascorbyl esters could be synthesized with high yields and retained (or even exceeded) free radical scavenging capacity of l-ascorbic acid, indicating prospects of broadening their application in emulsions and liposomes. PMID:25224149

  2. A free radical scavenger but not FGF-2-mediated angiogenic therapy rescues myonephropathic metabolic syndrome in severe hindlimb ischemia.

    PubMed

    Kaneko, Kazuhiro; Yonemitsu, Yoshikazu; Fujii, Takaaki; Onimaru, Mitsuho; Jin, Chen-Hao; Inoue, Makoto; Hasegawa, Mamoru; Onohara, Toshihiro; Maehara, Yoshihiko; Sueishi, Katsuo

    2006-04-01

    The therapeutic use of angiogenic factors shows promise in the treatment of critical limb ischemia; however, its potential for myonephropathic metabolic syndrome (MNMS), a fatal complication caused by arterial reconstruction, has not been elucidated. The objective of this study was to evaluate the effectiveness of recombinant Sendai virus-mediated gene transfer of fibroblast growth factor-2 (FGF-2) directly compared with that of a radical scavenger, MCI-186, in a rat model of MNMS. MNMS was surgically induced by aortic occlusion below renal arteries for 4 h, followed by 6 h of reperfusion. Administration of MCI-186 (twice; iv 5 min before induced ischemia and ip 5 min before reperfusion; 10 mg/kg, respectively), but not FGF-2 gene transfer (once, 48 h before induced ischemia), dramatically prevented the increase of serum biochemical markers as well as the edema of the gastrocnemius muscle. The effect of MCI-186 was accompanied by the marked suppression of the neutrophilic infiltration into the local (muscle) and remote (lung) organs. Although serum and muscular levels of a neutrophil-chemoattractant (growth-related oncogene/cytokine-induced neutrophil chemoattractant-1) were not affected by any treatment, the serum level of soluble intercellular adhesion molecule-1 was decreased by treatment with MCI-186 but not by treatment with FGF-2. These results suggest the distinct mechanism of MNMS from critical limb ischemia without reperfusion. Therefore, radical scavenging should be paid more attention than therapeutic angiogenesis when arterial circulation is reconstructed. PMID:16301206

  3. Effects of UV-B irradiation on the levels of anthocyanin, rutin and radical scavenging activity of buckwheat sprouts.

    PubMed

    Tsurunaga, Yoko; Takahashi, Tetsuya; Katsube, Takuya; Kudo, Akihide; Kuramitsu, Osamu; Ishiwata, Masaki; Matsumoto, Shingo

    2013-11-01

    The effects of various light compositions on the levels of anthocyanin, rutin and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity in buckwheat (Fagopyrum esculentum Moench) sprouts were evaluated. Dark-grown 6-day-old buckwheat sprouts were irradiated with different sources of visible and ultraviolet (UV) light. Particularly, we examined the effect of UV-B at wavelengths of 260-320 nm, 280-320 nm, and 300-320 nm on the production of flavonoid compounds, using multiple fluorescent lights and cylinders that filter out certain portions of the UV-B. The results showed that irradiation with UV-B>300 nm increased the levels of anthocyanin and rutin, as well as the DPPH radical scavenging activity. When sprouts were irradiated with UV-B light at wavelengths of 260-300 nm, yellowing or withering occurred within 24h of irradiation, indicating that wavelengths in this range are detrimental to the growth of buckwheat sprouts. PMID:23768393

  4. Isolation and structural determination of two novel phlorotannins from the brown alga Ecklonia kurome Okamura, and their radical scavenging activities.

    PubMed

    Yotsu-Yamashita, Mari; Kondo, Sawako; Segawa, Shinya; Lin, Yi-Chin; Toyohara, Haruhiko; Ito, Hisatomi; Konoki, Keiichi; Cho, Yuko; Uchida, Takafumi

    2013-01-01

    Two novel phlorotannins with a molecular weight of 974, temporarily named 974-A and 974-B, were isolated from the polyphenol powder prepared from the edible marine brown alga Ecklonia kurome Okamura, and their chemical structures were determined by spectroscopic method. The isolated yield of the total of 974-A and 974-B was approximately 4% (w/w) from the polyphenol powder. In 974-A, the carbon at the C2' position in the A ring of phlorofucofuroeckol-A forms a C-C bond with the carbon at the C2″ position of the C ring of triphloretol-B, while in 974-B, phlorofucofuroeckol-B and triphloretol-B form a C-C bond in the same manner as in 974-A. These structures were supported by high resolution-MS/MS data. To evaluate the antioxidant activities, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and intracellular radical scavenging assay, using 2',7'-dichlorofluorescin diacetate (DCFH-DA), were performed for 974-A, 974-B, and four known phlorotannins. The results of the DPPH assay showed that the IC(50) values of 974-A, 974-B, phlorofucofuroeckol-A, and dieckol were significantly smaller than those of phlorofucofuroeckol-B, phloroglucinol, α-tocopherol, and ascorbic acid. Furthermore, the DCFH-DA assay suggested that 974-A, 974-B, and dieckol reduce intracellular reactive oxygen species most strongly among the tested compounds. PMID:23334528

  5. Antioxidant activity and free radical scavenging capacity of phenolic extracts from Helicteres isora L. and Ceiba pentandra L.

    PubMed

    Loganayaki, Nataraj; Siddhuraju, Perumal; Manian, Sellamuthu

    2013-08-01

    In the present study, antioxidant activities of the phenolic extracts from H. isora fruits and C. pentandra seeds were investigated by employing established in vitro systems, which included reducing power, OH(●), DPPH(●), ABTS(●+), linoleic acid emulsion, metal chelation and antihemolytic activity. The extracts of C. pentandra contained relatively higher levels of total phenolics and flavonoids than those of H. isora. All the extracts showed dose dependent reducing power activity and moreover, they were well correlated with the total phenolic substances. A similar dose dependant trend has also been observed for hydroxyl radical scavenging activity and DPPH(●) radical scavenging activity. Further, addition of 250 μg of extracts to the reaction mixture produced 41.3-54.6% peroxidation inhibiting activity during 60 h of incubation. The potential of multiple antioxidant activity of samples can be further evidenced by inhibition of reactive oxygen mediated erythrocyte cell lysis and metal ion chelating activity. PMID:24425970

  6. Graphene scavenges free radicals to synergistically enhance structural properties in a gamma-irradiated polyethylene composite through enhanced interfacial interactions.

    PubMed

    Kolanthai, Elayaraja; Bose, Suryasarathi; Bhagyashree, K S; Bhat, S V; Asokan, K; Kanjilal, D; Chatterjee, Kaushik

    2015-09-21

    A unique strategy for scavenging free radicals in situ on exposure to gamma irradiation in polyethylene (PE) nanocomposites is presented. Blends of ultra-high molecular weight PE and linear low-density PE (PEB) and their nanocomposites with graphene (GPEB) were prepared by melt mixing to develop materials for biomedical implants. The effect of gamma irradiation on the microstructure and mechanical properties was systematically investigated. The neat blend and the nanocomposite were subjected to gamma-ray irradiation in order to improve the interfacial adhesion between PE and graphene sheets. Structural and thermal characterization revealed that irradiation induced crosslinking and increased the crystallinity of the polymer blend. The presence of graphene further enhanced the crystallinity via crosslinks between the polymer matrix and the filler on irradiation. Graphene was found to scavenge free radicals as confirmed by electron paramagnetic resonance spectroscopy. Irradiation of graphene-containing polymer composites resulted in the largest increase in modulus and hardness compared to either irradiation or addition of graphene to PEB alone. This study provides new insight into the role of graphene in polymer matrices during irradiation and suggests that irradiated graphene-polymer composites could emerge as promising materials for use as articulating surfaces in biomedical implants. PMID:26266702

  7. Composition and Free Radical Scavenging Activity of Kernel Oil from Torreya grandis, Carya Cathayensis, and Myrica R ubra.

    PubMed

    Ni, Liang; Shi, Wei-Yong

    2014-01-01

    In this study, we measured the composition and free radical scavenging activity of several species of nuts, namely, Torreya grandis, Carya cathayensis, and Myrica rubra. The nut kernels of the aforementioned species are rich in fatty acids, particularly in unsaturated fatty acids, and have 51% oil content. T. grandis and C. cathayensis are mostly produced in ZheJiang province. The trace elements in the kernels of T. grandis and C. cathayensis were generally higher than those in M. rubra, except for Fe with a value of 64.41 mg/Kg. T. grandis is rich in selenium (52.91-68.71 mg/Kg). All three kernel oils have a certain free radical scavenging capacity, with the highest value in M. rubra. In the DPPH assay, the IC50 of M. rubra kernel oil was 60 μg/mL, and OH was 100 μg/mL. The results of this study provide basic data for the future development of the edible nut resources in ZheJiang province. PMID:24734074

  8. HPLC analysis of vitamin E isoforms in human epidermis: correlation with minimal erythema dose and free radical scavenging activity.

    PubMed

    Fuchs, Jürgen; Weber, Stefan; Podda, Maurizio; Groth, Norbert; Herrling, Thomas; Packer, Lester; Kaufmann, Roland

    2003-02-01

    The content and composition of different vitamin E isoforms was analyzed in normal human skin. Interestingly the epidermis contained 1% alpha-tocotrienol, 3% gamma-tocotrienol, 87% alpha-tocopherol, and 9% gamma-tocopherol. Although the levels of tocotrienol in human epidermis appear to be considerably lower than reported in the hairless mouse, the presence of significant amounts of tocotrienol levels leads to speculation about the physiological function of tocotrienols in skin. Besides antioxidant activity and photoprotection, tocotrienols may have skin barrier and growth-modulating properties. A good correlation was found for epidermal alpha-tocopherol (r = 0.7909, p <.0003), gamma-tocopherol (r = 0.556, p <.025), and the total vitamin E content (r = 0.831, p <.0001) with the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging in epidermis, as assessed by electron paramagnetic resonance (EPR) spectroscopy. In human epidermis, alpha-tocopherol is quantitatively the most important vitamin E isoform present and comprises the bulk of first line free radical defense in the lipid compartment. Epidermal tocotrienol levels were not correlated with DPPH scavenging activity. The minimal erythema dose (MED), an individual measure for sun sensitivity and a crude indicator for skin cancer susceptibility, did not correlate with the epidermal content of the vitamin E isoforms. Hence it is concluded that vitamin E alone is not a determinant of individual photosensitivity in humans. PMID:12543248

  9. In vitro studies to assess the antioxidative, radical scavenging and arginase inhibitory potentials of extracts from Artocarpus altilis, Ficus exasperate and Kigelia africana

    PubMed Central

    Akanni, Olubukola Oyebimpe; Owumi, Solomon Eduviere; Adaramoye, Oluwatosin Adekunle

    2014-01-01

    Objective To justify the use of Artocarpus altilis (A. altilis), Ficus exasperata (F. exasperata) and Kigelia africana (K. africana) in ethnomedicine for the treatment of several ailments and to evaluate the in vitro antioxidant, radical scavenging and arginase inhibitory potentials of these herbs and compared with catechin (Standard). Methods Antioxidant activities were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide, hydrogen peroxide (H2O2) and hydroxyl (OH) radicals scavenging methods. The flavonoids and phenolics content, inhibition of arginase activity, Fe2+/ascorbate-induced lipid peroxidation (LPO) and reducing power were also determined. Results The A. altilis, F. exasperata and K. africana showed dose-dependent and significant scavenging of DPPH, H2O2 and OH radicals in vitro relative to catechin. The A. altilis and F. exasperata effectively scavenged DPPH radical with IC50 of 593 and 635 µg/mL and, OH radical with IC50 of 487 and 514 µg/mL, respectively. The DPPH and OH radicals scavenging activities followed the order A. altilis>F. exasperata>K. africana. In addition, A. altilis and F. exasperata significantly (P<0.05) inhibited LPO in a dose-dependent manner. The A. altilis extract had the most potent inhibitory activity against LPO with 79% relative to catechin (28%) at 750 µg/mL. The reducing power followed the order: A. altilis>Catechin>F. exasperata>K. africana at 1 000 µg/mL. The A. altilis at 500 and 750 µg/mL significantly (P<0.05) inhibited arginase activity by 63% and 67%, respectively. The flavonoids contents were found to be highest in A. altilis. Conclusions Extracts of A. altilis and F. exasperata are potent antioxidative agents with strong radical scavenging activity and inhibition of lipid peroxidation. PMID:25183137

  10. The scavenging of free radical and oxygen species activities and hydration capacity of collagen hydrolysates from walleye pollock ( Theragra chalcogramma) skin

    NASA Astrophysics Data System (ADS)

    Zhuang, Yongliang; Li, Bafang; Zhao, Xue

    2009-06-01

    Fish skin collagen hydrolysates (FSCH) were prepared from walleye pollock ( Theragra chalcogramma) using a mixture of enzymes, namely trypsin and flavourzyme. The degree of hydrolysis of the skin collagen was 27.3%. FSCH was mainly composed of low-molecular-weight peptides and the relative proportion of <1000Da fraction was 70.6%. Free radical and oxygen species scavenging activities of FSCH were investigated in four model systems, including diphenylpicrylhy-drazyl radical (DPPH), superoxide anion radical, hydroxyl radical and hydrogen peroxide model, and compared with that of a native antioxidant, reduced glutathione (GSH). FSCH was also evaluated by water-absorbing and water-holding capacity. The results showed that FSCH was able to scavenge free radical and oxygen species significantly and to enhance water-absorbing and water-holding capacity remarkably. Therefore, FSCH may have potential applications in the medicine and food industries.

  11. Studies on the syntheses, structural characterization, antimicrobial-, and DPPH radical scavenging activity of the cocrystals caffeine:cinnamic acid and caffeine:eosin dihydrate

    NASA Astrophysics Data System (ADS)

    Suresh Kumar, G. S.; Seethalakshmi, P. G.; Bhuvanesh, N.; Kumaresan, S.

    2013-10-01

    Two organic cocrystals namely, caffeine:cinnamic acid [(caf)(ca)] (1) and caffeine:eosin dihydrate [(caf)(eos)]·2H2O (2) were synthesized and studied by FT-IR, TGA/DTA, and single crystal XRD. The crystal system of cocrystal 1 is triclinic with space group P-1 and Z = 2 and that of cocrystal 2 is monoclinic with space group P21/C and Z = 4. An imidazole-carboxylic acid synthon is observed in the cocrystal 1. The intermolecular hydrogen bond, O-H⋯N and π-π interactions play a major role in stabilizing 1 whereas the intermolecular hydrogen bonds, O-H⋯O, O-H⋯N, and intramolecular hydrogen bond, O-H⋯Br; along with π-π interactions together play a vital role in stabilizing the structure of 2. The antimicrobial- and DPPH radical scavenging activities of both the cocrystals were studied.

  12. Non-extractable procyanidins and lignin are important factors in the bile acid binding and radical scavenging properties of cell wall material in some fruits.

    PubMed

    Hamauzu, Yasunori; Mizuno, Yukari

    2011-03-01

    The cell wall components and the food functions of alcohol-insoluble solids (AIS) of Chinese quince, quince, hawthorn, apple, pear and blueberry fruits were analyzed. Chinese quince contained characteristically high contents of cellulose, lignin, and non-extractable procyanidins (NEPCs). On the other hand, the quince AIS contained the highest proportion of NEPCs, the highest mean degree of polymerization (mDP), the strongest radical scavenging activity, and strong bile acid binding activity. In fruit AIS, the lignin and NEPC contents both showed positive correlations with the bile acid binding and radical scavenging activities. The value for mDP × NEPC content was a good index for the radical scavenging activity. The results suggest that highly polymerized NEPCs and lignin are important factors of cell wall components of fruits to having a high functionality, and Chinese quince and quince are interesting fruits from this view point. PMID:21243435

  13. Arbutin, an intracellular hydroxyl radical scavenger, protects radiation-induced apoptosis in human lymphoma U937 cells.

    PubMed

    Wu, Li-Hua; Li, Peng; Zhao, Qing-Li; Piao, Jin-Lan; Jiao, Yu-Fei; Kadowaki, Makoto; Kondo, Takashi

    2014-11-01

    Ionizing radiation (IR) can generate reactive oxygen species (ROS). Excessive ROS have the potential to damage cellular macromolecules including DNA, proteins, and lipids and eventually lead to cell death. In this study, we evaluated the potential of arbutin, a drug chosen from a series of traditional herbal medicine by measuring intracellular hydroxyl radical scavenging ability in X-irradiated U937 cells. Arbutin (hydroquinone-β-D-glucopyranoside), a naturally occurring glucoside of hydroquinone, has been traditionally used to treat pigmentary disorders. However, there are no reports describing the effect of arbutin on IR-induced apoptosis. We confirmed that arbutin can protect cells from apoptosis induced by X-irradiation. The combination of arbutin and X-irradiation could reduce intracellular hydroxyl radical production and prevent mitochondrial membrane potential loss. It also could down-regulate the expression of phospho-JNK, phospho-p38 in whole cell lysate and activate Bax in mitochondria. Arbutin also inhibits cytochrome C release from mitochondria to cytosol. To verify the role of JNK in X-irradiation-induced apoptosis, the cells were pretreated with a JNK inhibitor, and found that JNK inhibitor could reduce apoptosis induced by X-irradiation. Taken together, our data indicate that arbutin plays an anti-apoptotic role via decreasing intracellular hydroxyl radical production, inhibition of Bax-mitochondria pathway and activation of the JNK/p38 MAPK pathway. PMID:25187044

  14. Effect of gamma irradiation on the antimicrobial and free radical scavenging activities of Glycyrrhiza glabra root

    NASA Astrophysics Data System (ADS)

    Fatima Khattak, Khanzadi; James Simpson, Thomas

    2010-04-01

    The efficacy of gamma irradiation as a method of decontamination for food and herbal materials is well established. In the present study, Glycyrrhiza glabra roots were irradiated at doses 5, 10, 15, 20 and 25 kGy in a cobalt-60 irradiator. The irradiated and un-irradiated control samples were evaluated for phenolic contents, antimicrobial activities and DPPH scavenging properties. The result of the present study showed that radiation treatment up to 20 kGy does not affect the antifungal and antibacterial activity of the plant. While sample irradiated at 25 kGy does showed changes in the antibacterial activity against some selected pathogens. No significant differences in the phenolic contents were observed for control and samples irradiated at 5, 10 and 15 kGy radiation doses. However, phenolic contents increased in samples treated with 20 and 25 kGy doses. The DPPH scavenging activity significantly ( p<0.05) increased in all irradiated samples of the plant.

  15. Singlet oxygen quenching and radical scavenging capacities of structurally-related flavonoids present in Zuccagnia punctata Cav.

    PubMed

    Vieyra, Faustino E Morán; Boggetti, Héctor J; Zampini, Iris C; Ordoñez, Roxana M; Isla, María I; Alvarez, Rosa M S; De Rosso, Veridiana; Mercadante, Adriana Z; Borsarelli, Claudio D

    2009-06-01

    The singlet oxygen (1O2) quenching and free radical (DPPH(*), ABTS(* +) and O2(* -)) scavenging ability of three structurally-related flavonoids (7-hydroxyflavanone HF, 2',4'-dihydroxychalcone DHC and 3,7-dihydroxyflavone DHF) present in the Argentinean native shrub Zuccagnia punctata Cav. were studied in solution by combining electrochemical and kinetic measurements, mass spectroscopy, end-point antioxidant assays and computational calculations. The results showed that the antioxidant properties of these flavonoids depend on several factors, such as their electron- and hydrogen atom donor capacity, the ionization degree of the more acidic group, solvatation effects and electrostatic interactions with the oxidant species. The theoretical calculations for both the gas and solution phases at the B3LYP level of theory for the Osanger reaction field model agreed with the experimental findings, thus supporting the characterization of the antioxidant mechanism of the Z. punctata flavonoids. PMID:19431060

  16. Dipalmitoylphosphatidylcholine/linoleic acid mixed unilamellar vesicles as model membranes for studies on novel free-radical scavengers.

    PubMed

    Castelli, F; Trombetta, D; Tomaino, A; Bonina, F; Romeo, G; Uccella, N; Saija, A

    1997-04-01

    Large unilamellar vesicles (LUVs) are generally accepted to be a suitable model for peroxidation studies. In the present report, dipalmitoylphosphatidylcholine (DPPC)/linoleic acid-mixed LUVs were employed as model membranes to verify the inhibitory effect of tocopherol (an efficient representative antioxidant) against 2,2'-azobis(2-amidinopropane)hydrochloride-induced peroxidation (evaluated by monitoring conjugated diene accumulation). In this model, the appropriate experimental conditions (particularly, liposome composition and peroxidation temperature) were selected following characterization of bilayer physical state, and not only by evaluation of peroxidation rate. Thus, the experiments described provide a routine screening procedure that would be appropriate for assessing the activity profile of novel free-radical scavengers. PMID:9253749

  17. Optimization of Pyrogallol Autoxidation Conditions and Its Application in Evaluation of Superoxide Anion Radical Scavenging Capacity for Four Antioxidants.

    PubMed

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

    2016-03-01

    In this study, some factors influencing pyrogallol autoxidation, including EDTA, temperature, and solvent, were systematically investigated to improve its feasibility in the evaluation of antioxidants for the first time. Subsequently, the improved pyrogallol autoxidation conditions were used to assess the superoxide anion scavenging activity (SASA) of four commonly used antioxidants, namely, ascorbic acid, rutin, catechin, and gallic acid, by both the reaction rate method and the terminated method. The results indicate that pyrogallol autoxidation could be successfully used to determine the antioxidant capacity of ascorbic acid and rutin, which correspondingly suggests the feasibility of its use to measure the superoxide anion radical scavenging activity of polysaccharides and flavonols, because these compounds have a similar basic structural unit as ascorbic acid and rutin, respectively. Unexpectedly, however, pyrogallol autoxidation cannot be used to evaluate the SASA of catechin and gallic acid, although their good antioxidant capacity was confirmed by the 1,1-diphenyl-2-picrylhydrazyl assay. Together, these results suggest the importance of noting the conditions used for pyrogallol autoxidation when assessing the SASA of targeted compounds. PMID:26997318

  18. A comparative evaluation of mutagenic, antimutagenic, radical scavenging and antibacterial activities of essential oils of Pituranthos chloranthus (Coss. et Dur.).

    PubMed

    Neffati, Aicha; Limem, Ilef; Kilani, Soumaya; Bouhlel, Ines; Skandrani, Ines; Bhouri, Wissem; Ben Sghaier, Mohamed; Boubaker, Jihed; Ledauphin, Jerome; Barillier, Daniel; Ghedira, Leila Chekir; Ghedira, Kamel

    2009-01-01

    The Salmonella typhimurium/microsome assay is a widely used bacterial genotoxicity assay to test potential carcinogens. The aim of this work was to evaluate the mutagenic and antimutagenic activities with and without the addition of an extrinsic metabolic activation system of essential oils obtained from an aerial part of Pituranthos chloranthus harvested from different stations in Tunisia. The oils showed no mutagenicity when tested with S. typhimurium strains TA98, TA100, and TA1535. On the other hand, we showed that these essential oils reduced significantly Benzo [a] pyrene (B[a] P) and sodium-azide-induced mutagenicity. The scavenging capacity of these essential oils was also estimated by evaluating the inhibition of DPPH radical. Essential oils harvested at Medenine and Gabes in November were more effective in scavenging activity. The essential oils were tested for their antimicrobial properties against five different bacteria, and were found to be weakly active, with MIC and MBC values in the range 0.6-4 and 2.2-5 mg/mL, respectively. PMID:19793030

  19. Effect of dietary astaxanthin on free radical scavenging capacity and nitrite stress tolerance of postlarvae shrimp, Pleoticus muelleri.

    PubMed

    Díaz, Ana Cristina; Velurtas, Susana María; Espino, María Laura; Fenucci, Jorge Lino

    2014-12-24

    The aim of this study was to investigate the effect of astaxanthin feed supplementation and environmental nitrite stress in postlarvae of Pleoticus muelleri (15 ± 0.004 mg initial weight) under culture conditions. Diets containing three levels of astaxanthin, 0 mg kg(-1) of diet (C0), 100 mg kg(-1) of diet (C(100)), and 300 mg kg(-1) of diet (C(300)), were used. Postlarvae fed with each diet were exposed to different concentrations of nitrite (NO(2)Na) (0-200 mg L(-1)). The 96 h median lethal concentration (LC50) values of nitrite N were 76.3, 89.7, and 157 mg L(-1) for shrimps fed to C0, C(100), and C(300). The scavenging properties were evaluated against the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical by electron resonance spectroscopy (EPR). For all feed treatments, the extracts exhibited strong DPPH scavenging activity; however, shrimp fed with C(100) and C(300) showed the greatest activity to quench DPPH (62 and 59%, respectively) with respect to C0 (43%). It can be concluded that astaxanthin acts as a protector of nitrite stress in P. muelleri. PMID:25427235

  20. Modulation of arachidonic acid metabolism by phenols: relation to positions of hydroxyl groups and peroxyl radical scavenging properties.

    PubMed

    Alanko, J; Riutta, A; Mucha, I; Vapaatalo, H; Metsä-Ketelä, T

    1993-01-01

    We have shown earlier that catecholamines have opposite regulative effects on prostaglandin (PG)E2 and leukotriene (LT)B4 formation with a receptor-independent mechanism in human polymorphonuclear leukocytes (PMNs) and whole blood. To shed further light on the mechanisms involved and structure-action relationship, we tested the effects of phenols (catechol, hydroquinone, phenol, and resorcinol) on the synthesis of PGE2 and LTB4 in human A23187-stimulated PMNs. To study the mechanism of how phenols influence PGE2 and LTB4 synthesis, their peroxyl radical-scavenging properties were analyzed. In general, low concentrations of phenols stimulated (catechol > hydroquinone > phenol) and high concentrations inhibited (resorcinol > catechol > hydroquinone > phenol) PGE2 formation. Resorcinol was different from the other phenols: It did not stimulate PGE2 synthesis at all, but it was effective inhibitor at high concentrations. Phenols had only an inhibitory effect on LTB4 formation (catechol = hydroquinone > phenol > resorcinol). The order of both stochiometric factors and reactivities of phenols for scavenging peroxyl radicals was catechol > hydroquinone > resorcinol > phenol. According to these results, phenols having hydroxyl groups in ortho- or paraposition have the greatest stimulative effect on PGE2 synthesis, the highest inhibitory action on LTB4 synthesis, and are good antioxidants. Resorcinol, having hydroxyl groups in the metaposition, behaves differently. It neither stimulates PGE2 nor inhibits LTB4 formation, but it is the most potent inhibitor of PGE2 formation. In spite of resorcinol's two hydroxyl groups, it mimics as an antioxidant phenol more than catechol and hydroquinone. PMID:8384148

  1. Free radical scavenging ability of Aspalathus linearis in two in vitro models of diabetes and cancer

    PubMed Central

    Waisundara, Viduranga Y.; Hoon, Lee Yian

    2015-01-01

    The free radical scavenging activity of Aspalathus linearis (Rooibos tea) and its effect on reactive oxygen species (ROS), catalase (CAT), and superoxide dismutase (SOD) were investigated in two in vitro disease models of cancer and diabetes. Although the antioxidant activity of this tea has been reported in several studies, its effects in disease models of ROS-induced oxidative stress have not been systematically evaluated to date. The oxygen radical absorbance capacity (ORAC) assay was used in this study to quantify the antioxidant capacity of the extract, whereas the ROS scavenging ability in hyperglycemia-induced human umbilical vein endothelial cells (HUVECs) and HeLa cells were investigated. The CAT and SOD assays were also carried out in the two disease models in order to evaluate the effect of the extract in the stimulation of these two enzyme activities. The extract was observed to have reduced ROS in a dose-dependent manner in both HUVECs and HeLa cells. The stimulation of the CAT and SOD enzyme activities were observed to be dose-dependent as well. The high ORAC value of the extract indicated the presence of antioxidant compounds which could directly quench ROS, whereby this mechanism of action could be hypothesized to have been further complemented through the stimulation of CAT and SOD. Overall, the Aspalathus linearis extract was observed to have increased the CAT and SOD activities in two in vitro disease models of cancer and hyperglycemia. Given the correlation between the ORAC values, the increases in CAT and SOD activities and the reduction in ROS in a dose-dependent manner, it could be hypothesized that the extract had a significant therapeutic potential for either the prevention of the onset of the two diseases or their progression because ROS has been identified as their root causes. PMID:26151031

  2. Thioamides as radical scavenging compounds: Methods for screening antioxidant activity and detection.

    PubMed

    Chernov'yants, Margarita S; Kolesnikova, Tatiana S; Karginova, Anastasia O

    2016-03-01

    Heteroaromatic thiols and thiones attracted the attention of chemists, pharmacologists and biochemists because of participation in the interception of free radicals. For the first time offered independent and reliable methods for evaluating of the antioxidant activity of thioamides-derivatives of pyridine, quinoline, imidazole, triazole, tetrazole, pyrimidine, pyrrolidine and 7-mercapto-4-methylcoumarin -based on kinetic parameters of the thioamide reaction with chromogenic radical (rate constant, M(-1)min(-1) and time to decrease concentration of test free radical by 50%, TEC50, min) or thermodynamics of the thioamides reaction with molecular iodine (extent of thioamide conversion, %). To compare the antioxidant activity of thioamides and widely used standard-antioxidant Trolox (6-Hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid) we have proposed to use a value of relative antioxidant activity constant. As it was established, the kinetics of interaction between the chromogenic radical and thioamides in the presence of an excess of 2,2'-diphenyl-1-picrylhydrazyl (DPPH) is described by the kinetics of the pseudo first order with respect to the reacting components. A kinetic-spectrophotometric method for the quantification of heteroaromatic thioamides is elaborated and was tested in the analysis of urine. Thioamides were detected at concentrations of 1.53μgml(-1), RSD=4.6% (2-mercaptoimidazole, V), 2.08μgml(-1), RSD=1.8% (1-methylimidazoline-2-thione, VI), 1.45μgml(-1), RSD=4.3% (2-mercaptopyridine, IX).The proposed procedures show good precision and accuracy of the results obtained. PMID:26717847

  3. Proton-Coupled Electron-Transfer Mechanism for the Radical Scavenging Activity of Cardiovascular Drug Dipyridamole

    PubMed Central

    Barzegar, Abolfazl

    2012-01-01

    Dipyridamole (DIP) is a well-known pharmaceutical drug used as a coronary vasodilator and anti-platelet agent in clinics for treating several cardiovascular diseases. Primarily, the therapeutic effects of the drug are attributed to its antioxidant potency. In this research, we aim to declare the unknown antioxidant mechanism of DIP as well as its potent chain-breaking antioxidant activity in polar aqueous medium inside the cells, using different experimental methods and theoretical quantum calculations. Data demonstrated the higher antioxidant capacity of DIP against ROS and free radicals in polar cell's interior. DIP is capable of generating long living and noninvasive DIP• radicals in oxidant condition that leads to an effective “chain-breaking antioxidant” activity. Quantum computational data indicated that DIP antioxidant has more favorable ionization potential than trolox which means DIP has higher antioxidant activity. Also, data showed that the direct hydrogen-transfer is not a favorable process to construct DIP• because of high barrier energy, though electron-transfer process can more easily to produce DIP•+ with the lowest barrier energy. Altogether, the electron donating potency of DIP to reduce ferric ion, having the low anodic oxidation peak potential, producing long lived stable DIP• radicals and protecting myoblast cells from oxidation, proposed the excellent “chain-breaking antioxidant” potency via electron-transfer mechanism of this vasodilator DIP drug in polar aqueous medium. PMID:22745807

  4. Effects of natural free radical scavengers on peripheral nerve and neurovascular function in diabetic rats.

    PubMed

    Cotter, M A; Love, A; Watt, M J; Cameron, N E; Dines, K C

    1995-11-01

    Increased generation of reactive oxygen species, coupled with impaired endogenous scavenging mechanisms, plays a prominent role in the aetiology of neurovascular abnormalities in experimental diabetes mellitus. We examined the efficacy of the natural anti-oxidants vitamins C, E and beta-carotene in preventing nerve conduction and nutritive blood flow deficits in streptozotocin-diabetic rats. One month of diabetes caused a 19.1% reduction in sciatic motor conduction velocity (p < 0.001). This was approximately prevented 80-90% by high-dose (1000 mg.kg-1.day-1) vitamin E and beta-carotene treatments (p < 0.001). Vitamin C had lesser effects; the maximum protection found for motor conduction velocity was 36% using a dose of 150 mg.kg-1.day-1 (p < 0.001). High dose (500 mg.kg-1.day-1 (p < 0.001). High dose (500 mg.kg-1.day-1) vitamin C had a lesser effect on conduction than intermediate doses. Joint vitamin C and lower dose (500 mg.kg-1.day-1) vitamin E treatment had a predominantly additive preventive effect against nerve dysfunction. Resistance to hypoxic conduction failure for sciatic nerve in vitro was markedly increased by diabetes and this remained relatively unaffected by treatment. Sciatic nutritive endoneurial blood flow, measured using microelectrode polarography and hydrogen clearance, was reduced 46.1% by 1 month of diabetes (p < 0.001). This was prevented to the extent of 87%, 36% and 98% by vitamins E, C and beta-carotene, respectively (p < 0.01). These data emphasize the role of oxidative stress in the development of early neurovascular changes in experimental diabetes and show that naturally available scavengers have a neuroprotective action. PMID:8582537

  5. Increased endogenous ascorbyl free radical formation with singlet oxygen scavengers in reperfusion injury: an EPR and functional recovery study in rat hearts.

    PubMed

    Lee, J W; Bobst, E V; Wang, Y G; Ashraf, M M; Bobst, A M

    2000-12-01

    The objective of this study was to investigate the effect of singlet oxygen ((1)O2) scavengers on functional recovery and ascorbyl free radical (AFR) formation in isolated ischemic rat hearts. Hearts were subjected to 40 min. of global ischemia followed by 30 min. of reperfusion. Hemodynamics were measured as heart rate (HR), coronary flow (CF), left ventricular developed pressure (LVDP) and contractility (dP/dt). Electron paramagnetic resonance (EPR) spectroscopy was used to measure AFR release in coronary perfusate during the first two min. of reperfusion as a function of ROS scavengers. Relative to ischemic controls the administration of the (1)O2 scavengers 2,2,6,6-tetramethyl-4-piperidone x HCl (4-oxo-TEMP), carnosine (beta-alanyl-L-histidine) or a combination of the two significantly improved functional recovery as measured by LVDP. While no AFR signal was detected in coronary perfusate collected during preischemic perfusion with and without (1)O2 scavengers, the AFR background signal due to ischemia was significantly increased with the (1)O2 and *O2- scavengers. No such increase was observed with the hydroxyl radical (*OH) scavenger mannitol. Besides the AFR increase with the (1)O2 and *O2- scavengers the functional recovery was only significantly improved with the (1)O2 scavengers. In contrast to previous AFR studies we found with endogenous AFR that an increased AFR formation is not necessarily only reflecting increased oxidative stress but can also report improved functional recovery. Combining the hemodynamic data with increased AFR formation in the presence of several different ROS scavengers gives supportive evidence for (1)O2 also being involved in reperfusion injury. PMID:11156483

  6. Radical-scavenging Activity and Antioxidative Effects of Olive Leaf Components Oleuropein and Hydroxytyrosol in Comparison with Homovanillic Alcohol.

    PubMed

    Umeno, Aya; Takashima, Mizuki; Murotomi, Kazutoshi; Nakajima, Yoshihiro; Koike, Taisuke; Matsuo, Toshiki; Yoshida, Yasukazu

    2015-01-01

    Olive leaf has great potential as a natural antioxidant, and one of its major phenolic components is oleuropein. In this study, the antioxidant activity of oleuropein against oxygen-centered radicals was measured by examining its sparing effects on the peroxyl radical-induced decay of fluorescein and pyrogallol red, in comparison with related compounds. The antioxidant capacity of oleuropein against lipid peroxidation was also assessed through its effect on the free radical-induced oxidation of methyl linoleate in a micelle system. On a molar basis, oleuropein and hydroxytyrosol inhibited the decay of fluorescein for longer than both homovanillic alcohol and the vitamin-E mimic 2-carboxy-2,5,7,8-tetramethyl-6-chromanol (Trolox), but did not suppress pyrogallol red decay in a concentration-dependent manner. Measurement of the fluorescein decay period revealed that the stoichiometric number of oleuropein and hydroxytyrosol against peroxyl radicals was twice that of Trolox, which is substantially higher than expectations based on chemical structure. Oleuropein and hydroxytyrosol were also more effective than Trolox and homovanillic alcohol at suppressing the oxidation of methyl linoleate in the micelle system. Thus, both oleuropein and hydroxytyrosol exhibit high antioxidative activity against lipid peroxidation induced by oxygen-centered radicals, but the high reactivity of phenolic/catecholic radicals makes their mechanism of action complex. PMID:26136177

  7. Liquid chromatograpic-mass spectrometric analysis of phenolics and free radical scavenging activity of rosemary extract from different raw material.

    PubMed

    Almela, Luis; Sánchez-Muñoz, Blas; Fernández-López, José A; Roca, María J; Rabe, Virginia

    2006-07-01

    The antioxidant activity of rosemary (Rosmarinus officinalis) extract from different raw materials has been studied. Extracts were prepared from wild or drip-irrigated plants, as well as from the by-product resulting from the distillation of the aromatic essential oil. The radical scavenging activity of rosemary extracts was compared with that of antioxidants widely used in food, such as BHT and delta-tocopherol, using an optimization of the method based on the reduction of the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). The results pointed the excellent antioxidant activity of the crude fresh rosemary extracts, which was almost identical to that of pure delta-tocopherol, and higher than that of BHT; extracts prepared from distilled rosemary showed the lowest activity, although they are also of interest due to the low cost of the raw material. High performance liquid chromatography (HPLC) combined with diode array (DAD) and electrospray (ESI)-ion trap-MS detection was used to separate and identify the compounds present in the rosemary extracts. Rosmarinic acid, carnosic acid and seven of their terpene-type metabolites, and seven flavones were identified. The drying and/or distillation treatments used with the plant material strongly affected the content of the two compounds of higher antioxidant activity: rosmarinic acid and carnosic acid. PMID:16563403

  8. Assessment of haemolytic, cytotoxic and free radical scavenging activities of an underutilized fruit, Baccaurea ramiflora Lour. (Roxb.) Muell. Arg.

    PubMed

    Saha, Manas Ranjan; Dey, Priyankar; Chaudhuri, Tapas Kumar; Goyal, Arvind Kr; Sarker, Dilip De; Sen, Arnab

    2016-02-01

    Baccaurea ramiflora Lour. (Roxb.) Muell. Arg. is an underutilized juicy fruit bearing plant found in sub-Himalayan area, South China, Indo-Burma region, etc. The fruit is considered to be nutritive, and in this study, we evaluated its antioxidant, haemolytic and cytotoxic properties. The juice was examined for the quenching activity of hydroxyl radical, nitric oxide, singlet oxygen, peroxynitrite, total antioxidant activity (TAA), erythrocyte membrane stabilizing activity (EMSA) along with quantification of phenolic and flavonoid contents and also tested for its potential activity as iron chelator, inhibitor of lipid peroxidation and total reducing power. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were also performed to correlate antioxidant capacities with the phenolic and flavonoid content. Haemolytic activity on murine erythrocyte and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) cytotoxic test was performed on murine splenocytes, thymocytes, hepatocytes and peritoneal exudates macrophage to examine the cytotoxic effect of its juice. The result exhibited its potent free radical scavenging activity. In case of TAA, DPPH (2, 2-diphenyl-1-picrylhydrazyl), EMSA and lipid peroxidation, the fruit juice was found to have significant (P < 0.001) antioxidant capacity, which is evident from low IC50 (half maximal inhibitory concentration) value. Results obtained from haemolytic inhibition assay and MTT cytotoxic test confirms that the juice does not contain any cytotoxic effect and the fruit is safe for consumption. Fourier transform infrared (FTIR) spectra analysis exhibited high possibility of presence of flavonoid compounds in the juice. PMID:26934779

  9. Kinetic study of the radical scavenging of capsaicin in homogeneous solutions and aqueous Triton X-100 micellar suspensions.

    PubMed

    Watanabe, Atsushi; Seno, Shin-Ichiro; Kogure, Eiki; Seki, Kensuke; Sakamoto, Takeshi; Okada, Youji; Shimazu, Hideaki

    2015-03-01

    A kinetic study of capsaicin (CAP) toward radicals has been performed using stopped-flow spectrophotometry in detail. The second-order rate constants (k2) for the reaction of CAP toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) and galvinoxyl have been measured in methanol, ethanol, 2-propanol/water (5:1, v/v), and aqueous micellar suspensions containing 5% Triton X-100 (pH 4.0 to 10.0), respectively. The decay rates of DPPH and galvinoxyl for the reaction with CAP increased linearly in a concentration-dependent manner in homogeneous solutions and aqueous micellar suspensions. However, the k2 for CAP obtained in an aqueous micellar suspension showed notable pH dependence; that is, the reactivity of CAP increased with an increasing pH value from 4 to 10. In addition, a good correlation between the k2 value and the molar fraction of CAP (phenolate anion (CAP-O(-))/undeprotonated form (CAP-OH)) was observed. These properties are associated with the pKa of CAP. Furthermore, it was found that the CAP-O(-) reacts with galvinoxyl about 6 times as fast as the CAP-OH. These results indicate that sequential proton loss electron transfer from the phenolic hydrogen of CAP may be responsible for the scavenging of radicals in an aqueous micellar suspensions. PMID:25656650

  10. Effect of UV-C irradiation and low temperature storage on bioactive compounds, antioxidant enzymes and radical scavenging activity of papaya fruit.

    PubMed

    Rivera-Pastrana, Dulce M; Gardea, Alfonso A; Yahia, Elhadi M; Martínez-Téllez, Miguel A; González-Aguilar, Gustavo A

    2014-12-01

    Mature green 'Maradol' papaya fruits were exposed to ultraviolet (UV)-C irradiation (1.48 kJ·m(-2)) and stored at 5 or 14 °C. Changes in total phenols, total flavonoids, enzymatic activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), as well as the scavenging activity against 2,2-diphenyl-1picrylhydrazyl (DPPH) and 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radicals were investigated in peel and flesh tissues at 0, 5, 10 and 15 days of storage. UV-C irradiation increased significantly (P < 0.05) the flavonoid content (2.5 and 26 %) and ABTS radical scavenging activity (5.7 and 6 %) in flesh and peel at 14 °C respectively; and CAT activity (16.7 %) in flesh at 5 °C. Flavonoid contents, CAT and SOD activities were positively affected under low storage temperature (5 °C). DPPH and ABTS radical scavenging activities increased in both control and UV-C treated papaya peel during storage at 5 °C. UV-C irradiation effect on radical scavenging of papaya peel could be attributed to increased flavonoid content. Papaya antioxidant system was activated by UV-C and cold storage by increasing phenolic content and antioxidant enzymatic activities as a defense response against oxidative-stress. PMID:25477649

  11. Correlation of polyphenolic content with radical-scavenging capacity and anthelmintic effects of Rubus ulmifolius (Rosaceae) against Haemonchus contortus.

    PubMed

    Akkari, Hafidh; Hajaji, Soumaya; B'chir, Fatma; Rekik, Mourad; Gharbi, Mohamed

    2016-05-15

    Phenolic content, antioxidant and anthelmintic activities of herbal extracts are of particular interest to drug industry; plant extracts with significant anthelmintic activity have the potential to be used as alternatives to conventional chemical drugs. In the present study, Rubus ulmifolius fruit extracts obtained using solvents of increasing polarity (water, methanol, chloroform and hexane) were examined for their antioxidant and anthelmintic activities in correlation with their polyphenolic content. In vitro antioxidant activity of all extracts was carried out using free radical-scavenging activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethilenebenzotiazolin)-6-sulfonic acid (ABTS) radical cation. In vitro anthelmintic activities were investigated on the egg and adult worms of Haemonchus contortus from sheep in comparison to albendazole. Total polyphenol content of R. ulmifolius was higher in more polar extract, ranging from 64.5 in aqueous extract to 1.57mg gallic acid equivalents per gram of dry weight (GAE/g DW) in hexanic extract. Likewise, highest amounts of flavonoids and condensed tannins were found in aqueous extract (28.06mg QE/g and 7.42mg CE/g DW, respectively) compared to hexanic extract (0.71mg QE/g and 0.29mg CE/g DW, respectively) (p<0.05). Both DPPH and ABTS antioxidant assays showed that all tested extracts possess free radical scavenging activity, while the inhibitory concentration 50% (IC50) range values were similar for both assays (2.13-45.54μg/mL and 1.2-43.82μg/mL, respectively). All plant extracts showed ovicidal activity at all tested concentrations. Fruit methanolic (IC50=2.76mg/mL) and aqueous (IC50=2.08mg/mL) extracts showed higher inhibitory effects than chloroformic (IC50=7.62mg/mL) and hexanic (IC50=12.93mg/mL) extracts on egg hatching (p<0.05). There was a significant correlation of total polyphenol, flavonoids and tannins content with scavenging of either DPPH (r=0.722, 0.764 and 0.752, p<0

  12. Orally Bioavailable Metal Chelators and Radical Scavengers: Multifunctional Antioxidants for the Coadjutant Treatment of Neurodegenerative Diseases.

    PubMed

    Kawada, Hiroyoshi; Kador, Peter F

    2015-11-25

    Neurodegenerative diseases are associated with oxidative stress that is induced by the presence of reactive oxygen species and the abnormal cellular accumulation of transition metals. Here, a new series of orally bioavailable multifunctional antioxidants (MFAO-2s) possessing a 2-diacetylamino-5-hydroxypyrimidine moiety is described. These MFAO-2s demonstrate both free radical and metal attenuating properties that are similar to the original published MFAO-1s that are based on 1-N,N'-dimethylsulfamoyl-1-4-(2-pyrimidyl)piperazine. Oral bioavailability studies in C57BL/6 mice demonstrate that the MFAO-2s accumulate in the brain at significantly higher levels than the MFAO-1s while achieving similar neural retina levels. The MFAO-2s protect human neuroblastoma and retinal pigmented epithelial cells against hydroxyl radicals in a dose-dependent manner by maintaining cell viability and intracellular glutathione levels. The MFAO-2s outperform clioquinol, a metal attenuator that has been investigated for the treatment of Alzheimer's disease. PMID:26068053

  13. An in vivo and in vitro analysis of free radical scavenging potential possessed by Desmodium gangeticum chloroform root extract: interpretation by gsms.

    PubMed

    Srivats, Shyam; Ramakrishnan, Gomathi; Paddikkala, Jose; Kurian, Gino Andrew

    2012-01-01

    In the present study, the effect of DG chloroform root extract was assessed on isolated rat heart and in-vitro antioxidant models. Ischemia reperfusion injury was experimentally induced by using Langendroff apparatus. The free radical scavenging potential was studied in vitro by using different antioxidant models such as DPPH, super oxide scavenging activity, hydroxide scavenging activity and nitric oxide scavenging activity. Both experimental approaches not only substantiate its antioxidant potential but also the cardio-protection imparted by the extract. The cardio-stimulatory effects were investigated for the extract by treating it as a pre-conditioning agent against myocardial ischemia reperfusion injury. The improved antioxidant status of the myocardium indirectly predicts reduced oxidative stress mediated by ischemic reperfusion with evident reduction of infarct size determined by cardiac marker protein. These findings indicate that DG chloroform root extract may possess therapeutic potential against ischemia reperfusion injury. PMID:22186306

  14. Evaluation of free radical-scavenging and antihemolytic activities of quince (Cydonia oblonga) leaf: a comparative study with green tea (Camellia sinensis).

    PubMed

    Costa, Rossana M; Magalhães, Ana S; Pereira, José A; Andrade, Paula B; Valentão, Patrícia; Carvalho, Márcia; Silva, Branca M

    2009-04-01

    This study aimed to determine the phenolic profile and to investigate the antioxidant potential of quince (Cydonia oblonga) leaf, comparing it with green tea (Camellia sinensis). For these purposes, methanolic extracts were prepared and phenolics content of quince leaf was determined by HPLC/UV. The antioxidant properties were assessed by Folin-Ciocalteu reducing capacity assay and by the ability to quench the stable free radical 2,2'-diphenyl-1-picrylhydrazyl (DPPH) and to inhibit the 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative hemolysis of human erythrocytes.5-O-Caffeoylquinic acid was found to be the major phenolic compound in quince leaf extract. Quince leaf exhibited a significantly higher reducing power than green tea (mean value of 227.8 +/- 34.9 and 112.5 +/- 1.5 g/kg dry leaf, respectively). Quince leaf extracts showed similar DPPH radical-scavenging activities (EC50 mean value of 21.6 +/- 3.5 microg/ml) but significantly lower than that presented by green tea extract (EC50 mean value of 12.7 +/- 0.1 microg/ml). Under the oxidative action of AAPH, quince leaf methanolic extract significantly protected the erythrocyte membrane from hemolysis in a similar manner to that found for green tea (IC50 mean value of 30.7 +/- 6.7 and 24.3 +/- 9.6 microg/ml, respectively, P > 0.05). These results point that quince leaf may have application as preventive or therapeutic agent in diseases in which free radicals are involved. PMID:19271320

  15. In vitro studies on α-glucosidase inhibition, antioxidant and free radical scavenging activities of Hedyotis biflora L.

    PubMed

    Nimal Christhudas, I V S; Praveen Kumar, P; Sunil, Christudas; Vajravijayan, S; Lakshmi Sundaram, R; Jenifer Siril, S; Agastian, P

    2013-06-01

    Aim of this study was to evaluate the in vitro α-glucosidase inhibition and antioxidant activity of hexane, ethyl acetate and methanol extracts of Hedyotis biflora L. (Rubiaceae). In in vitro α-glucosidase inhibition and antioxidant activity, the methanol extract showed potent effect compared to hexane and ethyl acetate extracts. The methanol extract of H. biflora (HBMe) showed 50% α-glucosidase inhibition at the concentration of 480.20 ± 2.37 μg/ml. The total phenolic content of HBMe was 206.81 ± 1.11 mg of catechol equivalents/g extract. HBMe showed great scavenging activity on 2,2-diphenyl-picrylhydrazyl (DPPH) (IC(50) 520.21 ± 1.02 μg/ml), hydroxyl (IC(50) 510.21 ± 1.51 μg/ml), nitric oxide (IC(50) 690.20 ± 2.13 μg/ml) and superoxide (IC(50) 510.31 ± 1.45 μg/ml) radicals, as well as high reducing power. HBMe also showed a strong suppressive effect on lipid peroxidation. Using the β-carotene method, the scavenging values of HBMe was significantly lower than BHT, and metal chelating ability of HBMe also showed a strong inhibition effect when compared to the reference standard. The active compound ursolic acid from HBMe was identified using various spectroscopical studies. The results obtained in this study clearly indicate that HBMe has a significant potential to use as a natural α-glucosidase inhibition, antioxidant agent. PMID:23411299

  16. Oxidative stress induction of DJ-1 protein in reactive astrocytes scavenges free radicals and reduces cell injury

    PubMed Central

    Yanagida, Takashi; Tsushima, Jun; Yanagisawa, Daijiro; Takata, Kazuyuki; Shibaike, Tomonori; Yamamoto, Atsuko; Taniguchi, Takashi; Yasui, Hiroyuki; Taira, Takahiro; Morikawa, Shigehiro; Inubushi, Toshihiro; Tooyama, Ikuo

    2009-01-01

    Astrocytes, one of the predominant types of glial cells, function as both supportive and metabolic cells for the brain. Under cerebral ischemia/reperfusion-induced oxidative conditions, astrocytes accumulate and activate in the ischemic region. DJ-1 has recently been shown to be a sensor of oxidative stress in living cells. However, the function of astrocytic DJ-1 is still unknown. In the present study, to clarify the effect of astrocytic DJ-1 protein under massive oxidative insult, we used a focal ischemic rat model that had been subjected to middle cerebral artery occlusion (MCAO) and reperfusion. We then investigated changes in the distribution of DJ-1 in astrocytes, DJ-1 release from cultured astrocytes, and the effects of recombinant DJ-1 protein on hydrogen peroxide (H2O2)-induced death in normal and DJ-1-knockdown SH-SY5Y cells and on in vitro scavenging of hydroxyl radicals (•OH) by electron spin resonance spectrometry. At 24 h after 2-h MCAO and reperfusion, an infarct lesion was markedly observed using magnetic resonance imaging and 2,3,5-triphenyltetrazolium chloride staining. In addition, reactive astrocytes enhanced DJ-1 expression in the penumbral zone of the ischemic core and that DJ-1 protein was extracellularly released from astrocytes by H2O2 in in vitro primary cultures. Although DJ-1-knockdown SH-SY5Y cells were markedly vulnerable to oxidative stress, treatment with glutathione S-transferase-tagged recombinant human DJ-1 protein (GST-DJ-1) significantly inhibited H2O2-induced cell death. In addition, GST-DJ-1 protein directly scavenged •OH. These results suggest that oxidative stress induces the release of astrocytic DJ-1 protein, which may contribute to astrocyte-mediated neuroprotection. PMID:20046643

  17. An exploratory study on the peroxyl-radical-scavenging activity of 2,6-dimethyl-5-hepten-2-ol and its heterocyclic analogues

    NASA Astrophysics Data System (ADS)

    Stobiecka, Agnieszka; Sikora, Magdalena; Bonikowski, Radosław; Kula, Józef

    2016-03-01

    The structural properties and radical scavenging activity of 2,6-dimethyl-5-hepten-2-ol (1) and its new heterocyclic analogues, i.e. 2-methyl-4-(5-methylfuran-2-yl)-butan-2-ol (2) and 2-methyl-4-(5-methylthiophen-2-yl)-butan-2-ol (3) and have been studied by using the experimental and theoretical methods for the first time. Activity of title compounds against the peroxyl radical was determined by using standard fluorimetric test, i.e. the Oxygen Radical Absorbance Capacity assay (ORACFL). Furthermore, the electron-donating ability of odorants has been evaluated by using colorimetric ABTS assay. According to the experimental results obtained from the ORACFL test 2,6-dimethyl-5-hepten-2-ol was characterized by the highest activity in comparison with the novel counterparts. Nevertheless, all investigated compounds exhibited pronounced anti-peroxyl radical activity comparable to that exerted by the one of the most prominent antioxidant among the monoterpene alcohols, i.e. by linalool. On the other hand, the title compounds exerted relatively low capacity to quench the radical cation of ABTS. Theoretical calculations based on the Density Functional Theory (DFT) method with the hybrid functional B3LYP were carried out in order to investigate selected structural and electronic properties including the geometrical parameters as well as the energy of frontier molecular orbitals of parent molecules and the resulting radicals. Furthermore, the possible mechanism of peroxyl-radical-scavenging has been determined by using the thermodynamic descriptors such as the bond dissociation enthalpies (BDEs) and ionization potentials (IPs). These theoretical data pointed out the relevance of HAT mechanism in the peroxyl-radical-scavenging exhibited by 2,6-dimethyl-5-hepten-2-ol and its new heterocyclic analogues in polar and non-polar medium.

  18. The effects of combined free radical scavenger and sildenafil therapy on age-associated erectile dysfunction: An animal model

    PubMed Central

    Kovac, Jason R.; DeYoung, Ling; Lehmann, Kyle J.; Chung, Eric; Brock, Gerald B.

    2014-01-01

    Introduction: Aging results in erectile dysfunction that is partially attributed to decreased nitric oxide (NO) and increased free radical generation. Vitamin E enhances endothelial cell function and acts as a free radical scavenger; however, its benefits on erectile function in the elderly are unknown. Aims: The aim of the following study is to determine if Vitamin E alone, or in combination with the phosphodiesterase 5 inhibitor sildenafil, may improve erectile function and the NO signaling in a cohort of aged (13-15 month old) rats. Materials and Methods: Male Sprague-Dawley rats (n = 28) were divided based upon age into young (4-5 months old, n = 7) and aged (13-15 months old, n = 21) cohorts. Aged rats were treated with Vitamin E, sildenafil or a combination of both. Penile cavernosal and dorsal nerve tissues were evaluated for neuronal nitric oxide synthase (nNOS) and caveolin-1 expression. Erectile function was assessed through intra-cavernous pressure (ICP) recordings. Results: nNOS and cavoelin-1 were significantly decreased in aged rats compared with young controls. In aged rats, both Vitamin E and sildenafil partially recovered nNOS expression but when combined, a synergistic elevation in nNOS was observed. The significant decreases in ICP recorded in aged rats were improved with sildenafil; however, Vitamin E did not yield any additional improvements in ICP. Conclusions: Diminished levels of nNOS and caveolin-1 are found in aged rats. When combined with sildenafil, Vitamin E synergistically increased nNOS expression. Since biochemical gains were not realized physiologically, other contributing factors likely exist. PMID:25371608

  19. Kinetic Study of Aroxyl-Radical-Scavenging and α-Tocopherol-Regeneration Rates of Five Catecholamines in Solution: Synergistic Effect of α-Tocopherol and Catecholamines.

    PubMed

    Mukai, Kazuo; Nagai, Kanae; Egawa, Yoshifumi; Ouchi, Aya; Nagaoka, Shin-Ichi

    2016-07-28

    Detailed kinetic studies have been performed for reactions of aroxyl (ArO(•)) and α-tocopheroxyl (α-Toc(•)) radicals with five catecholamines (CAs) (dopamine (DA), norepinephrine (NE), epinephrine (EN), and 5- and 6-hydroxydopamine (5- and 6-OHDA)) and two catechins (epicatechin (EC) and epigallocatechin gallate (EGCG)) to clarify the free-radical-scavenging activity of CAs. Second-order rate constants (ks and kr) for reactions of ArO(•) and α-Toc(•) radicals with the above antioxidants were measured in 2-propanol/water (5:1, v/v) solution at 25.0 °C, using single- and double-mixing stopped-flow spectrophotometries, respectively. Both the rate constants (ks and kr) increased in the order NE < EN < DA < EC < 5-OHDA < EGCG < 6-OHDA. The ks and kr values of 6-OHDA are large and comparable to the corresponding values of ubiquinol-10 and sodium ascorbate, which show high free-radical-scavenging activity. The ultraviolet-visible absorption of α-Toc(•) (λmax = 428 nm), which was produced by the reaction of α-tocopherol (α-TocH) with ArO(•), disappeared under the coexistence of CAs due to the α-TocH-regeneration reaction. The results suggest that the CAs may contribute to the protection from oxidative damage in nervous systems, by scavenging free radicals (such as lipid peroxyl radical) and regenerating α-TocH from the α-Toc(•) radical. PMID:27346174

  20. The detection of radical scavenging compounds in crude extract of borage (Borago officinalis L.) by using an on-line HPLC-DPPH method.

    PubMed

    Bandoniene, Donata; Murkovic, Michael

    2002-01-01

    The rapid evaluation of antioxidant activity of crude borage (Borago officinalis L.) extract was determined by using DPPH free radical method. This borage extract resulted in a rapid decrease of the absorbance and showed very high hydrogen-donating capacity towards the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical. A new HPLC-DPPH on-line method was applied for a screening of several radical scavenging components in this borage extract as well as for quantitative analysis. This on-line HPLC-DPPH method was developed using a methanolic solution of DPPH-stable radical. The HPLC-separated analytes reacted post-column with the DPPH solution in methanol. The induced bleaching was detected as a negative peak photometrically at 515 nm. The separation of antioxidative components was carried out by gradient HPLC with mobile-phase composition ranging from 2% to 80% acetonitrile with 2% acetic acid in water, UV detection was carried out at 280 nm. The HPLC analysis of borage extract revealed the presence of several radical scavenging components in the borage extract. The results obtained from the chromatograms suggest that some compounds present in the extract possess high radical quenching ability. The dominant antioxidative compound in the crude extract of borage leaves was identified as rosmarinic acid. PMID:12406585

  1. Comparison of the radical scavenging potential of polar and lipidic fractions of olive oil and other vegetable oils under normal conditions and after thermal treatment.

    PubMed

    Valavanidis, Athanasios; Nisiotou, Christala; Papageorgiou, Yiannis; Kremli, Ioulia; Satravelas, Nikolaos; Zinieris, Nikolaos; Zygalaki, Helen

    2004-04-21

    The antioxidant activity (IC(50)) of extra virgin olive oil (EVOO), commercial olive oil, and other vegetable oils (soybean, sunflower, and corn oil) was determined by UV-vis and by electron paramagnetic resonance (EPR) spectroscopy of the stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). Also, we studied the antioxidant activity of the methanol soluble phase (methanolic, MF) and the nonsoluble phase (lipidic, LF) of oils by the same methods. Similarly, we studied the effect of heating on the antioxidant activity at 160 and 190 degrees C. Also, the MF, containing the polyphenolic substances, was used for measurements of the radical scavenging capacity toward the most important oxygen free radicals, superoxide anion (O(2)(*)(-)) and hydroxyl (HO(*)) radicals. Results showed that soybean oil and EVOO had the highest antioxidant potential and thermal stability. In the case of soybean oil, the antioxidant capacity is the result of its high content of gamma- and delta-tocopherols (with the highest antioxidant capacity and thermostabilities), whereas in EVOO, the antioxidant potential is the result of the combination of specific antioxidant polyphenols, which are acting additionally as effective stabilizers of alpha-tocopherol. The high content of EVOO in tyrosol, hydrotyrosol, and oleuropein and other polyphenolics with radical scavenging abilities toward superoxide anion and hydroxyl radical suggests that olive oil possesses biological properties that could partially account for the observed beneficial health effects of the Mediterranean diet. PMID:15080646

  2. Free radical scavenging and anti-oxidative activities of an ethanol-soluble pigment extract prepared from fermented Zijuan Pu-erh tea.

    PubMed

    Fan, Jiang Ping; Fan, Chong; Dong, Wen Min; Gao, Bin; Yuan, Wei; Gong, Jia Shun

    2013-09-01

    An ethanol-soluble pigment extract was separated from fermented Zijuan Pu-erh tea. The compositions of the ethanol soluble pigment extract were analyzed by high-performance liquid chromatography-tandem mass spectroscopy (HPLC-MS/MS). The extract was prepared into a series of ethanol solutions and analyzed for free radical-scavenging activities (against two free radicals: 1,1-diphenyl-2-picrylhydrazyl (DPPH) and (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO)) and in vitro anti-oxidative properties. Electron spin resonance spectroscopy showed that the peaks of DPPH and TEMPO decreased with increasing extract concentration, suggesting that the extract had excellent free radical-scavenging activities. In vitro cell culture suggested that, at 50-200 mg/L, the extract had no measurable effect on the viability of vascular endothelial cells (ECV340) but produced significant protective effects for cells that underwent oxidative injuries due to hydrogen peroxide (H₂O₂) treatment. Compared with the H₂O₂ treatment alone cells group, 200 mg/L of the extract increased the activity of superoxide dismutase (SOD) in cells by 397.3%, and decreased the concentration of malondialdehyde (MDA) and the activity of lactate acid dehydrogenase (LDH) by 47.8% and 69.6%, respectively. These results suggest that the extract has excellent free radical scavenging and anti-oxidative properties. PMID:23831194

  3. Radical scavenging activities of Tyr-, Trp-, Cys- and Met-Gly and their protective effects against AAPH-induced oxidative damage in human erythrocytes.

    PubMed

    Zheng, Lin; Dong, Hongzhu; Su, Guowan; Zhao, Qiangzhong; Zhao, Mouming

    2016-04-15

    Radical scavenging activities of Tyr-, Trp-, Cys- and Met-Gly and their protective effects against AAPH-induced oxidative damage in erythrocytes were evaluated in this study. This damage includes hemolysis, oxidation of hemoglobin, formation of MDA and the depletion of glutathione (GSH) and catalase (CAT). Results showed that Tyr- and Trp-Gly could quench the radicals effectively in ABTS and ORAC assays with TE (Trolox equivalent) values of more than 1.0 μmol TE/μmol, followed by Cys- and Met-Gly. All these dipeptides could protect erythrocytes against AAPH-induced hemolysis in a dose-dependent manner. They could also significantly (p<0.05) retard the oxidation of hemoglobin and depletion of GSH in erythrocytes. The protective effects of these dipeptides decreased in the following order: Trp-Gly>Tyr-Gly>Met-Gly>Cys-Gly, which were consistent with their peroxyl radical scavenging activities. It suggested that these dipeptides might protect erythrocytes against AAPH-induced oxidative damage, mainly by acting as the direct radical scavengers. PMID:26617020

  4. In vitro synthesis of betaxanthins using recombinant DOPA 4,5-dioxygenase and evaluation of their radical-scavenging activities.

    PubMed

    Sekiguchi, Hiroshi; Ozeki, Yoshihiro; Sasaki, Nobuhiro

    2010-12-01

    Betalamic acid, the chromophore of betaxanthins, was enzymatically synthesized on a large scale from l-dihydroxyphenylalanine (L-DOPA) using recombinant Mirabilis jalapa DOPA 4,5-dioxygenase. After synthesis, proline was directly added to the concentrated reaction mixture to generate proline-betaxanthin. The molecular mass and nuclear magnetic resonance spectrum of the purified product were identical to those previously reported for proline-betaxanthin. Twenty-four betaxanthin species were synthesized by the condensation reaction of purified betalamic acid and amino acids or amines. An HPLC protocol was established for identifying the different betaxanthin species. Proline-, dopamine-, and γ-aminobutyric acid (GABA)-betaxanthins were prepared as representative betaxanthins under large-scale conditions, and their 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activities were compared against those of known antioxidants. GABA-betaxanthin showed comparatively low activity, whereas dopamine-betaxanthin had similar activity to the red pigment betanin and the anthocyanin cyanidin 3-glucoside. Proline-betaxanthin had the highest activity of the three synthesized compounds and was similar to the flavonoid quercetin. PMID:21058725

  5. Syntheses, structural characterization, and DPPH radical scavenging activity of cocrystals of caffeine with 1- and 2-naphthoxyacetic acids

    NASA Astrophysics Data System (ADS)

    Suresh Kumar, G. S.; Seethalakshmi, P. G.; Sumathi, D.; Bhuvanesh, N.; Kumaresan, S.

    2013-03-01

    Caffeine:1-naphthoxyacetic acid [(caf)(1-naa)] and caffeine:2-naphthoxyacetic acid [(caf)(2-naa)] cocrystals have been synthesized and single crystals were grown by slow evaporation technique. The structures of the grown crystals were elucidated using single crystal X-ray diffraction analysis. Both the cocrystals belong to the monoclinic crystallographic system with space group P21/c, Z = 4, and α = γ = 90°, whereas β = 111.4244(18)° for [(caf)(1-naa)] and β = 109.281(6)° for [(caf)(2-naa)]. The crystal packing is predominantly stabilized by hydrogen bonding and π-π stacking interactions. The presence of unionized -COOH functional group in both the cocrystals was identified by FTIR spectral analysis. Thermal behavior and stability of both the cocrystals were studied by TGA/DTA analyses. Solvent-free formation of these cocrystals was confirmed by powder X-ray diffraction analyses. The theoretical energy of cocrystals showed that the formers have higher energy than cocrystals 1 and 2. DPPH radical scavenging activity of cocrystals 1 and 2 is slightly greater than the formers.

  6. Free Radical Scavenging, Cytotoxic and Hemolytic Activities from Leaves of Acacia nilotica (L.) Wild. ex. Delile subsp. indica (Benth.) Brenan

    PubMed Central

    Kalaivani, T.; Rajasekaran, C.; Suthindhiran, K.; Mathew, Lazar

    2011-01-01

    Dietary intake of phytochemicals having antioxidant activity is associated with a lower risk of mortality from many diseases. Therefore, the aim of this study was to determine the free radical scavenging, cytotoxic and hemolytic activities of leaves of Acacia nilotica by using various methods. The results of the present study revealed that ethanol extract was the most effective and IC50 value was found to be 53.6 μg mL−1 for Vero cell lines and 28.9 μg mL−1 for Hela cell lines in cytotoxicity assays. The zone of color retention was 14.2 mm in β-carotene bleaching assay, which was as significant as positive control, butylated hydroxy toluene. None of the tested extracts possessed any hemolytic activity against rat and human erythrocytes revealing their cytotoxic mechanism and non-toxicity. Thus, only the ethanol extract could be considered as a potential source of anticancer and antioxidant compounds. Further phytochemical studies will be performed for specification of the biologically active principles. PMID:21799676

  7. Free radical scavenging activity and comparative metabolic profiling of in vitro cultured and field grown Withania somnifera roots.

    PubMed

    Senthil, Kalaiselvi; Thirugnanasambantham, Pankajavalli; Oh, Taek Joo; Kim, So Hyun; Choi, Hyung Kyoon

    2015-01-01

    Free radical scavenging activity (FRSA), total phenolic content (TPC), and total flavonoid content (TFC) of in vitro cultured and field grown Withania somnifera (Ashwagandha) roots were investigated. Withanolides analysis and comprehensive metabolic profiling between 100% methanol extracts of in vitro and field grown root tissues was performed using high performance thin layer chromatography (HPTLC) and gas chromatography-mass spectrometry (GC-MS), respectively. Significantly higher levels of FRSA, TPC, and TFC were observed in in-vitro cultured roots compared with field grown samples. In addition, 30 day-cultured in vitro root samples (1 MIR) exhibited a significantly higher FRSA (IC50 81.01 μg/mL), TPC (118.91 mg GAE/g), and TFC (32.68 mg CE/g) compared with those in 45 day-cultured samples (1.5 MIR). Total of 29 metabolites were identified in in vitro cultured and field grown roots by GC-MS analysis. The metabolites included alcohols, organic acids, purine, pyrimidine, sugars, and putrescine. Vanillic acid was only observed in the in vitro cultured root samples, and higher level of the vanillic acid was observed in 1 MIR when compared to 1.5 MIR. Therefore, it is suggested that 1 MIR might serve as an alternative to field grown roots for the development of medicinal and functional food products. PMID:25874568

  8. Effect of high oxygen atmosphere storage on quality, antioxidant enzymes, and DPPH-radical scavenging activity of Chinese bayberry fruit.

    PubMed

    Yang, Zhenfeng; Zheng, Yonghua; Cao, Shifeng

    2009-01-14

    The influence of high O(2) atmosphere on postharvest decay, quality, total phenolic, total anthocyanin contents, antioxidant enzymes activity, and antioxidant activity of Chinese bayberry fruit was investigated. Freshly harvested Chinese bayberry fruits were placed in jars and ventilated continuously with air or with 80 and 100% O(2) for up to 12 days. Samples were randomly selected initially and at 3-days interval during storage. The fruit exposed to high O(2) was resistant to decay, had high levels of total soluble solids, titratable acidity and ascorbic acid contents, and also reduced the increment of pH value. High O(2) treatment was less stressful as reflected by having the significantly lower malonaldehyde contents and higher catalase, ascorbic acid peroxidase, and peroxidase activities during storage. Both 80% and 100% O(2) treaments had also retained the bioactive contents and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity during storage. These results indicate that elevated O(2) levels may improve the ability of the antioxidative defense mechanism in Chinese bayberry and result in a better control of fruit decay. PMID:19093866

  9. Free Radical Scavenging Activity and Comparative Metabolic Profiling of In Vitro Cultured and Field Grown Withania somnifera Roots

    PubMed Central

    Senthil, Kalaiselvi; Thirugnanasambantham, Pankajavalli; Oh, Taek Joo; Kim, So Hyun; Choi, Hyung Kyoon

    2015-01-01

    Free radical scavenging activity (FRSA), total phenolic content (TPC), and total flavonoid content (TFC) of in vitro cultured and field grown Withania somnifera (Ashwagandha) roots were investigated. Withanolides analysis and comprehensive metabolic profiling between 100% methanol extracts of in vitro and field grown root tissues was performed using high performance thin layer chromatography (HPTLC) and gas chromatography-mass spectrometry (GC-MS), respectively. Significantly higher levels of FRSA, TPC, and TFC were observed in in-vitro cultured roots compared with field grown samples. In addition, 30 day-cultured in vitro root samples (1MIR) exhibited a significantly higher FRSA (IC50 81.01 μg/mL), TPC (118.91 mg GAE/g), and TFC (32.68 mg CE/g) compared with those in 45 day-cultured samples (1.5MIR). Total of 29 metabolites were identified in in vitro cultured and field grown roots by GC-MS analysis. The metabolites included alcohols, organic acids, purine, pyrimidine, sugars, and putrescine. Vanillic acid was only observed in the in vitro cultured root samples, and higher level of the vanillic acid was observed in 1MIR when compared to 1.5MIR. Therefore, it is suggested that 1MIR might serve as an alternative to field grown roots for the development of medicinal and functional food products. PMID:25874568

  10. In Vitro Propagation, Phytochemical Analysis, and Evaluation of Free Radical Scavenging Property of Scrophularia kakudensis Franch Tissue Extracts

    PubMed Central

    Manivannan, Abinaya; Soundararajan, Prabhakaran; Park, Yoo Gyeong; Jeong, Byoung Ryong

    2015-01-01

    The current study deals with in vitro propagation, antioxidant property estimation, and assessment of acacetin content in Scrophularia kakudensis Franch. Adventitious shoot induction was achieved from the nodal explant with the highest number of adventitious shoots per explant (17.4) on Murashige and Skoog's (MS) medium fortified with 2.0 mg·L−1 6-benzyladenine (BA) and 0.5 mg L−1 indole-3-acetic acid (IAA). Maximum number of roots per plant (16.5) was noted in half strength MS medium supplemented with 0.5 mg·L−1 IAA. The regenerated plants displayed successful survival ratio (95%) in the greenhouse. The highest content of acacetin, a pharmaceutically important flavonoid, was observed in the shoot extracts (in vitro: 32.83 µg·g−1 FW; in vivo: 30.05 µg·g−1 FW) followed by root extracts. Total phenol and flavonoid contents along with free radical scavenging assays revealed the occurrence of larger amount of antioxidants in shoot extract in comparison with callus and root extracts of S. kakudensis. Thus, the outcome of the present study can be highly beneficial for the germplasm conservation and commercial cultivation of S. kakudensis for therapeutic purposes. PMID:26649304

  11. New Oxidovanadium Complexes Incorporating Thiosemicarbazones and 1, 10-Phenanthroline Derivatives as DNA Cleavage, Potential Anticancer Agents, and Hydroxyl Radical Scavenger.

    PubMed

    Ying, Peng; Zeng, Pengfei; Lu, Jiazheng; Chen, Hongyuan; Liao, Xiangwen; Yang, Ning

    2015-10-01

    Four novel oxidovanadium(IV) complexes, [VO(hntdtsc)(PHIP)] (1) (hntdtsc = 2-hydroxy-1-naphthaldehyde thiosemicarbazone, PHIP= 2-phenyl-imidazo[4,5-f]1,10-phenanthroline), [VO(hntdtsc)(DPPZ)](2)(DPPZ= dipyrido[3,2-a:2',3'-c]phenazine), [VO(satsc)(PHIP)](3) (satsc=salicylaldehyde thiosemicarbazone), and [VO(satsc)(DPPZ)](4), have been prepared and characterized. The chemical nuclease activities and photocleavage reactions of the complexes were tested. All four complexes can efficiently cleave pBR322 DNA, and complex 1 has the best cleaving ability. The antitumor properties of these complexes were examined with three different tumor cell lines using MTT assay. Their antitumor mechanism has been analyzed using cell cycle analysis, fluorescence microscopy of apoptosis, and Annexin V-FITC/PI assay. The results showed that the growth of human neuroblastoma (SH-SY5Y, SK-N-SH) and human breast adenocarcinoma (MCF-7) cells were inhibited significantly with very low IC50 values. Complex 1 was found to be the most potent antitumor agent among the four complexes. It can cause G0/G1 phase arrest of the cell cycle and exhibited significant induced apoptosis in SK-N-SH cells and displayed typical morphological apoptotic characteristics. In addition, they all displayed reasonable abilities to scavenge hydroxyl radical, and complex 1 was the best inhibitor. PMID:25659415

  12. In Vivo Processing of Ceria Nanoparticles inside Liver: Impact on Free-Radical Scavenging Activity and Oxidative Stress

    PubMed Central

    Tseng, Michael T.; Jasinski, Jacek B.; Yokel, Robert A.; Unrine, Jason M.; Davis, Burtron H.; Dozier, Alan K.; Hardas, Sarita S.; Sultana, Rukhsana; Grulke, Eric A.; Allan Butterfield, D.

    2015-01-01

    The cytotoxicity of ceria ultimately lies in its electronic structure, which is defined by the crystal structure, composition, and size. Despite previous studies focused on ceria uptake, distribution, biopersistance, and cellular effects, little is known about its chemical and structural stability and solubility once sequestered inside the liver. Mechanisms will be presented that elucidate the in vivo transformation in the liver. In vivo processed ceria reveals a particle-size effect towards the formation of ultrafines, which represent a second generation of ceria. A measurable change in the valence reduction of the second-generation ceria can be linked to an increased free-radical scavenging potential. The in vivo processing of the ceria nanoparticles in the liver occurs in temporal relation to the brain cellular and protein clearance responses that stem from the ceria uptake. This information is critical to establish a possible link between cellular processes and the observed in vivo transformation of ceria. The temporal linkage between the reversal of the pro-oxidant effect (brain) and ceria transformation (liver) suggests a cause–effect relationship. PMID:26322251

  13. Changes of hydrogen peroxide and radical-scavenging activity of raspberry during osmotic, convective, and freeze-drying.

    PubMed

    Novaković, Miroslav M; Stevanović, Snežana M; Gorjanović, Stanislava Ž; Jovanovic, Predrag M; Tešević, Vele V; Janković, Miodrag A; Sužnjević, Desanka Ž

    2011-05-01

    This study was conducted to investigate the influence of different drying treatments on antioxidant (AO) activity and phenolic content of raspberry (Rubus idaeus), cultivar Willamette. Whole raspberry fruits were dried convectively (air-drying), osmotically, and freeze-dried. Acetone-water extracts of fresh and dried raspberries were assessed for total phenolic content by standard Folin-Ciocalteau method. Two AO assays were applied, a recently developed direct current (DC) polarographic assay based on decrease of anodic oxidation current of hydrogen peroxide and widely used radical scavenge against the 1,1-diphenyl-2-picrylhydrazyl (DPPH). Strong correlation has been obtained between both AO assays and total phenolic content. In addition, some individual phenolic compounds present in raspberry have been assessed using DPPH and DC polarographic assay. Comparison and evaluation of drying methods has been based on preservation of AO activity and total phenolic content. Obtained results confirmed superiority of freeze-drying; convective drying caused slight changes while osmotic dehydration showed a significant decrease of phenolic compounds and AO activity. PMID:22417351

  14. GANRA-5 protects both cultured cells and mice from various radiation types by functioning as a free radical scavenger.

    PubMed

    Pei, H; Chen, W; Hu, W; Zhu, M; Liu, T; Wang, J; Zhou, G

    2014-06-01

    The radio-protective effects of the oxazolone derivative chemical compound 4-(4-methoxy-3-methoxyphenyl-methyl)-2-phenyl- 5(4H)-oxazolone (GANRA-5) against different types of radiation including X-rays, carbon ion beams, microwaves and ultraviolet light (UV) were studied. Cell proliferation/cytotoxicity assay and colony-forming assay were conducted to evaluate the toxicity of GANRA-5. To test its influence on the induction of double-stranded break (DSB) formation and genomic instability, γH2AX focus-forming assay as well as cytokinesis-block micronucleus assay was utilized. Our results indicate that GANRA-5 exhibits low toxicity, while providing high radio-protective effects for MRC-5 cells against different types of radiation. We also found that GANRA-5 acts as a free radical scavenger. Our animal studies provided evidence that GANRA-5 significantly increases the survival rate of mice after X-ray irradiation. Analyses of hemogram, visceral index and detection of superoxide dismutase (SOD) and malondialdehyde (MDA) in the viscera indicate both low toxicity of GANRA-5, combined with its ability to shield radiation risk. In conclusion, our results suggest that GANRA-5 has the potential to be used as a safe and efficient radio-protectant. PMID:24580122

  15. Pharmacognostic standardization, antioxidant and free radical scavenging activity of the seeds of Triticum aestivum L - A dietary staple

    PubMed Central

    Khan, Ghulam M.; Ansari, Shahid H.; Ahmad, Feroz

    2013-01-01

    Aims To establish the Quality standards of Triticum aestivum L, seeds as per WHO guidelines. To study the antioxidant and hepatoprotective profile of T. aestivum L. seeds. Methods Pharmacognostic studies like morphological, microscopical, physico-chemical, phytochemical evaluation, fluorescence analysis, TLC, HPTLC, phytochemical analysis etc. of various extracts of the seeds of T. aestivum were carried out as per established methods. The ethanolic extract was evaluated for antioxidant and hepatoprotective activity using rat model. Results Preliminary phytochemical analysis mainly revealed the presence of carbohydrates, phenolics, proteins, resins, lipids and flavonoids. T. aestivum at different doses, i.e. 5-45 μg/ml showed free radical scavenging activity in dose dependent manner. The amount of phenolic components was found to be 313.5 μg/mg indicating considerable antioxidant activity. The ethanolic extract of T. aestivum was administered at dose level of 100 mg/kg/day, every day for 21 days along with CCl4. Biochemical and histopathological results conclude that the seeds have hepatoprotective activity. PMID:24023455

  16. Correlation of In Vivo and In Vitro Assay Results for Assessment of Free Radical Scavenging Activity of Green Tea Nutraceuticals.

    PubMed

    Abd-ElSalam, Heba-Alla H; Al-Ghobashy, Medhat A; Al-Shorbagy, Muhammad; Nassar, Noha; Zaazaa, Hala E; Ibrahim, Mohamed A

    2016-07-01

    Green tea (GT)-derived catechins; epigallocatechin gallate (EGCG) in particular are commonly used nutraceuticals for their free-radical scavenging activity (FRSA). The influence of photodegradation on the protective power of GT nutracenticals against oxidative stress was thoroughly explored. Photodegradation of GT extracts was carried out and monitored using orthogonal stability-indicating testing protocol; in vitro and in vivo assays. Total polyphenol content (TPC) and FRSA were determined spectrophotometrically while EGCG was selectively monitored using SPE-HPLC. In vivo assessment of photodegraded samples was investigated via measuring a number of biomarkers for hepatic oxidative stress and apoptosis (caspase-3, inducible nitric oxide synthase, nitric oxide, mitogen-activated protein kinase, glutathione, thiobarbituric acid reactive substances, nuclear factor kappa beta, and nuclear factor erythroid 2-related factor) as well as liver damage (alanine transaminase and aspartate transaminase) in serum of rats previously subjected to oxidative stress. Results showed complete degradation of EGCG in photodegraded green tea samples with no correlation with either TPC or FRSA. On the other hand, in vivo assay results revealed not only loss of activity but formation of harmful pro-oxidants. Photostability was found crucial for the protective effect of GT extract against lead acetate insult. Results confirmed that careful design of quality control protocols requires correlation of chemical assays to bioassays to verify efficacy, stability, and most importantly safety of nutraceuticals. PMID:27275932

  17. Beneficial effect of the oxygen free radical scavenger amifostine (WR-2721) on spinal cord ischemia/reperfusion injury in rabbits

    PubMed Central

    Chronidou, Fany; Apostolakis, Efstratios; Papapostolou, Ioannis; Grintzalis, Konstantinos; Georgiou, Christos D; Koletsis, Efstratios N; Karanikolas, Menelaos; Papathanasopoulos, Panagiotis; Dougenis, Dimitrios

    2009-01-01

    Background Paraplegia is the most devastating complication of thoracic or thoraco-abdominal aortic surgery. During these operations, an ischemia-reperfusion process is inevitable and the produced radical oxygen species cause severe oxidative stress for the spinal cord. In this study we examined the influence of Amifostine, a triphosphate free oxygen scavenger, on oxidative stress of spinal cord ischemia-reperfusion in rabbits. Methods Eighteen male, New Zealand white rabbits were anesthetized and spinal cord ischemia was induced by temporary occlusion of the descending thoracic aorta by a coronary artery balloon catheter, advanced through the femoral artery. The animals were randomly divided in 3 groups. Group I functioned as control. In group II the descending aorta was occluded for 30 minutes and then reperfused for 75 min. In group III, 500 mg Amifostine was infused into the distal aorta during the second half-time of ischemia period. At the end of reperfusion all animals were sacrificed and spinal cord specimens were examined for superoxide radicals by an ultra sensitive fluorescent assay. Results Superoxide radical levels ranged, in group I between 1.52 and 1.76 (1.64 ± 0.10), in group II between 1.96 and 2.50 (2.10 ± 0.23), and in group III (amifostine) between 1.21 and 1.60 (1.40 ± 0.19) (p = 0.00), showing a decrease of 43% in the Group of Amifostine. A lipid peroxidation marker measurement ranged, in group I between 0.278 and 0.305 (0.296 ± 0.013), in group II between 0.427 and 0.497 (0.463 ± 0.025), and in group III (amifostine) between 0.343 and 0.357 (0.350 ± 0.007) (p < 0.00), showing a decrease of 38% after Amifostine administration. Conclusion By direct and indirect methods of measuring the oxidative stress of spinal cord after ischemia/reperfusion, it is suggested that intra-aortic Amifostine infusion during spinal cord ischemia phase, significantly attenuated the spinal cord oxidative injury in rabbits. PMID:19758462

  18. Natural anthraquinone derivatives from a marine mangrove plant-derived endophytic fungus Eurotium rubrum: structural elucidation and DPPH radical scavenging activity.

    PubMed

    Li, Dong-Li; Li, Xiao-Ming; Wang, Bin-Gui

    2009-07-01

    There is considerable interest in the isolation of potent radical scavenging compounds from natural resources to treat diseases involving oxidative stress. In this report, four new fungal metabolites including one new bisdihydroanthracenone derivative (1, eurorubrin), two new seco-anthraquinone derivatives [3, 2-O-methyl-9-dehydroxyeurotinone and 4, 2-Omethyl- 4-O-(alpha-D-ribofuranosyl)-9-dehydroxyeurotinone], and one new anthraquinone glycoside [6, 3-O-(alpha-D-ribofuranosyl)- questin], were isolated and identified from Eurotium rubrum, an endophytic fungal strain that was isolated from the inner tissue of the stem of the marine mangrove plant Hibiscus tiliaceus. In addition, three known compounds including asperflavin (2), 2-O-methyleurotinone (5), and questin (7) were also isolated and identified. Their structures were elucidated on the basis of spectroscopic analysis. All of the isolated compounds were evaluated for 1,1-diphenyl-2-picrylhydrazyl(DPPH) radical scavenging activity. PMID:19652514

  19. Radical scavenging capacity of 2,4-dihydroxy-9-phenyl-1H-phenalen-1-one: a functional group exclusion approach.

    PubMed

    Duque, Luisa; Zapata, Carolina; Rojano, Benjamín; Schneider, Bernd; Otálvaro, Felipe

    2013-07-19

    2,4-Dihydroxy-9-phenyl-1H-phenalen-1-one (4-hydroxyanigorufone, 1), a compound isolated from Anigozanthos flavidus and Monochoria elata, displayed a high radical scavenging capacity in the ORAC assay. A systematic approach was adopted in order to explore the effect of each functional group. H-Atom transfer from the phenolic hydroxyl, a captodative effect from the hydroxy ketone, and the presumed involvement of the phenyl ring in the termination step of the radical reaction were disclosed as relevant features of this type of antioxidant. PMID:23834597

  20. Radical-Scavenging Activity and Ferric Reducing Ability of Juniperus thurifera (L.), J. oxycedrus (L.), J. phoenicea (L.) and Tetraclinis articulata (L.).

    PubMed

    El Jemli, Meryem; Kamal, Rabie; Marmouzi, Ilias; Zerrouki, Asmae; Cherrah, Yahia; Alaoui, Katim

    2016-01-01

    Objective. The aim of this work is to study and compare the antioxidant properties and phenolic contents of aqueous leaf extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus Phoenicea, and Tetraclinis articulata from Morocco. Methods. Antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging ability, Trolox equivalent antioxidant capacity (TEAC), and ferric reducing antioxidant power (FRAP) assays. Also the total phenolic and flavonoids contents of the extracts were determined spectrophotometrically. Results. All the extracts showed interesting antioxidant activities compared to the standard antioxidants (butylated hydroxytoluene (BHT), quercetin, and Trolox). The aqueous extract of Juniperus oxycedrus showed the highest antioxidant activity as measured by DPPH, TEAC, and FRAP assays with IC50 values of 17.91 ± 0.37 μg/mL, 19.80 ± 0.55 μg/mL, and 24.23 ± 0.07 μg/mL, respectively. The strong correlation observed between antioxidant capacities and their total phenolic contents indicated that phenolic compounds were a major contributor to antioxidant properties of these plants extracts. Conclusion. These results suggest that the aqueous extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus phoenicea, and Tetraclinis articulata can constitute a promising new source of natural compounds with antioxidants ability. PMID:27293428

  1. Radical-Scavenging Activity and Ferric Reducing Ability of Juniperus thurifera (L.), J. oxycedrus (L.), J. phoenicea (L.) and Tetraclinis articulata (L.)

    PubMed Central

    Kamal, Rabie; Marmouzi, Ilias; Zerrouki, Asmae; Cherrah, Yahia; Alaoui, Katim

    2016-01-01

    Objective. The aim of this work is to study and compare the antioxidant properties and phenolic contents of aqueous leaf extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus Phoenicea, and Tetraclinis articulata from Morocco. Methods. Antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging ability, Trolox equivalent antioxidant capacity (TEAC), and ferric reducing antioxidant power (FRAP) assays. Also the total phenolic and flavonoids contents of the extracts were determined spectrophotometrically. Results. All the extracts showed interesting antioxidant activities compared to the standard antioxidants (butylated hydroxytoluene (BHT), quercetin, and Trolox). The aqueous extract of Juniperus oxycedrus showed the highest antioxidant activity as measured by DPPH, TEAC, and FRAP assays with IC50 values of 17.91 ± 0.37 μg/mL, 19.80 ± 0.55 μg/mL, and 24.23 ± 0.07 μg/mL, respectively. The strong correlation observed between antioxidant capacities and their total phenolic contents indicated that phenolic compounds were a major contributor to antioxidant properties of these plants extracts. Conclusion. These results suggest that the aqueous extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus phoenicea, and Tetraclinis articulata can constitute a promising new source of natural compounds with antioxidants ability. PMID:27293428

  2. Comparative analysis of radical scavenging and antioxidant activity of phenolic compounds present in everyday use spice plants by means of spectrophotometric and chromatographic methods.

    PubMed

    Stankevičius, Mantas; Akuņeca, Ieva; Jãkobsone, Ida; Maruška, Audrius

    2011-06-01

    Comparative analysis of radical scavenging and antioxidant activities of phenolic compounds present in everyday use spice plants was carried out by means of spectrophotometric and chromatographic methods. Six spice plant samples, namely onion (Allium cepa), parsley (Petroselinum crispum) roots and leaves, celery (Apium graveolens) roots and leaves and leaves of dill (Anethum graveolens) were analyzed. Total amount of phenolic compounds and radical scavenging activity (RSA) was the highest in celery leaves and dill extracts and was the lowest in celery roots. Comparing commonly used spectrophotometric analysis of 2,2-diphenyl-1-picrylhydrazyl (DPPH) RSA of extracts with the results obtained using reversed-phase chromatographic separation with on-line post-column radical scavenging reaction detection, good correlation was obtained (R(2)=0.848). Studies using HPLC system with electrochemical detector showed that bioactive phytochemicals can be separated and antioxidant activities of individual compounds evaluated without the need of a complex HPLC system with reaction detector. The results obtained using electrochemical detection correlate with the RSA assayed using spectrophotometric method (R(2)=0.893). PMID:21504067

  3. Chemical Characterization, Free Radical Scavenging, and Cellular Antioxidant and Anti-Inflammatory Properties of a Stilbenoid-Rich Root Extract of Vitis vinifera

    PubMed Central

    Esatbeyoglu, Tuba; Ewald, Philipp; Yasui, Yoshiaki; Yokokawa, Haruka; Wagner, Anika E.; Matsugo, Seiichi; Winterhalter, Peter; Rimbach, Gerald

    2016-01-01

    Dietary stilbenoids are receiving increasing attention due to their potential health benefits. However, most studies concerning the bioactivity of stilbenoids were conducted with pure compounds, for example, resveratrol. The aim of this study was to characterize a complex root extract of Vitis vinifera in terms of its free radical scavenging and cellular antioxidant and anti-inflammatory properties. HPLC-ESI-MS/MS analyses of the root extract of Vitis vinifera identified seven stilbenoids including two monomeric (resveratrol and piceatannol), two dimeric (trans-ɛ-viniferin and ampelopsin A), one trimeric (miyabenol C), and two tetrameric (r-2-viniferin = vitisin A and r-viniferin = vitisin B) compounds which may mediate its biological activity. Electron spin resonance and spin trapping experiments indicate that the root extract scavenged 2,2-diphenyl-1-picrylhydrazyl, hydroxyl, galvinoxyl, and superoxide free radicals. On a cellular level it was observed that the root extract of Vitis vinifera protects against hydrogen peroxide-induced DNA damage and induces Nrf2 and its target genes heme oxygenase-1 and γ-glutamylcysteine synthetase. Furthermore, the root extract could induce the antiatherogenic hepatic enzyme paraoxonase 1 and downregulate proinflammatory gene expression (interleukin 1β, inducible nitric oxide synthase) in macrophages. Collectively our data suggest that the root extract of Vitis vinifera exhibits free radical scavenging as well as cellular antioxidant and anti-inflammatory properties. PMID:26788254

  4. Toxicological Evaluation of Emblica officinalis Fruit Extract and its Anti-inflammatory and Free Radical Scavenging Properties

    PubMed Central

    Middha, Sushil Kumar; Goyal, Arvind Kumar; Lokesh, Prakash; Yardi, Varsha; Mojamdar, Lavanya; Keni, Deepthi Sudhir; Babu, Dinesh; Usha, Talambedu

    2015-01-01

    Background: Emblica officinalis (Euphorbiaceae), popularly known as Indian gooseberry or “Amla” in India, is used in Ayurveda as “rejuvenating herb” since ancient times. Objective: This study was carried out to estimate toxicity, anti-inflammatory, and antioxidative activities of the methanolic extract of Emblica officinalis fruit (MEO) in an animal model. Materials and Methods: Antioxidative property of MEO was assessed by in vitro assays such as phosphomolybdenum assay (total antioxidant capacity), free radical scavenging assays 1,1-diphenyl-2-picrylhydrazyl and 2,2’-azino-bis and 3-ethylbenzthiazoline-6-sulphonic acid (DPPH and ABTS method) and lipid peroxidation assay (LPO). The anti-inflammatory property was evaluated by carrageenan-induced acute inflammation in rats by measuring rat paw volume at different time intervals and toxicological analysis using mice. Results and Discussion: High performance liquid chromatography studies revealed the presence of gallic acid (2.10%), mucic acid (4.90%), ellagic acid (2.10%), quercetin (28.00%), rutin (3.89%), and β-glucogallin (1.46%). MEO showed highest antioxidant activities by using DPPH (17.33–89.00%), ABTS (23.03–94.16%), nitric oxide scavenging activity (12.94–70.16%), LPO (56.54%), and phosphomolybdenum assay (142 ± 6.09 μg/ml). The LD50 was found to be approximately 1125 mg/kg (p.o). High dose of MEO showed significant reduction (72.71%) in the inflammation after 4 h of treatment, which was comparable to diclofenac (10 mg/kg) (61.57%) treated group. Significant reduction (P < 0.05) in the inflammatory cytokine (interleukin-1β and tumor necrosis factor-α) markers were also observed (57.25% and 35.41%, respectively) in serum of MEO treated animals as compared to control. Conclusion: Taken together, phenolic compounds of MEO may serve as a potential herbal drug for amelioration of acute inflammation due to their modulatory action on free radicals. SUMMARY The methanolic extract of Emblica

  5. Effect of PDE5 inhibition combined with free oxygen radical scavenger therapy on erectile function in a diabetic animal model.

    PubMed

    De Young, L; Yu, D; Freeman, D; Brock, G B

    2003-10-01

    Phosphodiesterase (PDE) inhibitors represent an important advance in the treatment of erectile dysfunction (ED). In spite of widespread use and generally good efficacy, as a class they remain ineffective in 15-57% of men. Specific cohorts of patients with severe vascular or neurogenic basis to their ED, such as diabetic men or those who have undergone radical pelvic surgery, demonstrate lower response rates with PDE inhibition treatment. We believe that circulating levels of nitric oxide (NO) may be enhanced through delivery of adequate concentrations of free oxygen radical scavenger molecules such as vitamin E. Higher levels of NO, theoretically, should produce increased penile blood flow with the potential for a synergistic effect when combined with a PDE5 inhibitor. With this hypothesis in mind, 20 adult male Sprague-Dawley streptozotocin-induced (60 mg/kg i.p.) diabetic rats were divided into four therapeutic groups (n=5). Group I--control animals received peanut oil, group II--vitamin E 20 IU/day, group III--sildenafil 5 mg/kg/day and group IV--vitamin E 20 IU/day plus sildenafil 5 mg/kg/day, by oral gavage daily for 3 weeks. Erectile function was assessed as a rise in intracavernous pressure following cavernous nerve electrostimulation. Penile tissue was harvested to determine the changes in tissue morphology including neuronal nitric oxide synthase, smooth muscle alpha-actin and endothelial cell integrity. PDE5 protein content and activity were measured. Significant increases in intracavernous pressure were measured in the animals receiving combined vitamin E plus sildenafil treatment. Immunohistochemical staining showed increases of neuronal nitric oxide synthase, endothelial cell and smooth muscle cell staining. Western blot analysis did not show significant differences of PDE5 protein between the groups. However, higher PDE5 activity was measured in the sildenafil group and lower activity of PDE5 was recorded in the cohort receiving vitamin E with

  6. Antityphoid and radical scavenging properties of the methanol extracts and compounds from the aerial part of Paullinia pinnata.

    PubMed

    Lunga, Paul Keilah; Tamokou, Jean de Dieu; Fodouop, Simeon Pc; Kuiate, Jules-Roger; Tchoumboue, Joseph; Gatsing, Donatien

    2014-01-01

    Paullinia pinnata Linn (Sapindaceae) is a medicinal plant, locally used in the West Region of Cameroon for the treatment of typhoid fever. This work was designed to evaluate the antityphoid and antioxidant activities of the extracts and compounds of P. pinnata. The methanol extracts of the leaves and stems were tested for antityphoid and antioxidant activities. Compounds were isolated, and their structures elucidated by analysis of spectroscopic data in conjuction with literature data and tested for the same activities. The leaf extract was also tested in vivo for its antityphoid potential in a Salmonella typhimurium-induced typhoid fever model in Wistar rats. Seven known compounds: methylinositol (1), β-sitosterol (2), friedelin (3), 3β-(β-D-Glucopyranosyloxy)stigmast-5-ene (4), (3β)-3-O-(2'-Acetamido-2'-deoxy-β-D-glucopyranosyl) oleanolic acid (5), (3β,16α-hydroxy)-3-O-(2'-Acetamido-2'-deoxy-β-D-glucopyranosyl) echinocystic acid (6) and (3β,)-3-O-[β-D-glucopyranosyl-(1″-3')-2'-acetamido-2'-deoxy-β-D-galactopyranosyl]oleanolic acid (7) were isolated. Compounds 5 and 1 showed the highest antibacterial (MIC = 0.781-1.562 μg/ml) and DPPH radical scavenging (RSa50 = 19.27 ± 4.43 μg/ml) activities respectively. The maximum extract dose (446.00 mg/kg bw) had comparable activity with ciprofloxacin (7.14 mg/kg bw) and oxytetracycline (5 mg/kg bw). The extract induced significant dose-dependent increase of WBCs and lymphocytes. These results support the ethnomedicinal use of P. pinnata and its isolated Compounds could be useful in the standardization of antityphoid phytomedicine from it. PMID:25279277

  7. Inhibition of lipid oxidation and rancidity in precooked pork patties by radical-scavenging licorice (Glycyrrhiza glabra) extract.

    PubMed

    Jiang, Jiang; Zhang, Xin; True, Alma D; Zhou, Lirong; Xiong, Youling L

    2013-11-01

    This study investigated the efficacy of licorice extract (LE) to curtail lipid oxidation and protect sensory attributes of ground pork during refrigerated and frozen storage. Pork patties (20% fat) were formulated with 0%, 0.02%, 0.05%, and 0.1% (meat basis) LE or rosemary extract (RE) as comparison or 0.01% (fat basis) BHA with 0 or 1.5% NaCl. Raw and precooked (75 °C) patties were packaged in polyvinylchloride overwrapped trays and stored at 2 °C up to 7 and 14 d, respectively, or at -20 °C up to 6 mo. Lipid oxidation (thiobarbituric acid-reactive substances [TBARS]) and sensory attributes of stored patty samples were evaluated, radical scavenging activity of the LE was measured, and the active phenolic compounds were identified. Cooking yield (<85%) was similar among antioxidant treatments, and lipid oxidation was minimal in refrigerated or frozen raw samples. However, TBARS values in refrigerated precooked control patties (0.22 mg/kg) rose to 9.3 to 9.4 mg/kg after 14 d, compared to 3.4 to 4.4 and 4.4 to 6.9 mg/kg in patties treated with 0.1% LE and RE, respectively. In frozen precooked samples, TBARS (0.22 mg/kg) increased to 1.3 mg/kg (P < 0.05) in control patties after 6 mo and had no significant change in patties treated with 0.1% LE or 0.01% butylated hydroxyanisol. Sensory panel evaluation confirmed strong inhibition of rancidity production by LE, corroborating its remarkable antiradical activity due to the presence of multiple phenolics. The results indicate that licorice has great potential as a natural antioxidative additive to extend the shelf-life of precooked pork. PMID:24245886

  8. The flavonoid content and antiproliferative, hypoglycaemic, anti-inflammatory and free radical scavenging activities of Annona dioica St. Hill

    PubMed Central

    2013-01-01

    Background Annona dioica St. Hill (Annonacaeae) is a Brazilian plant used in folk medicine for the treatment of several types of rheumatisms and diarrhoea. The focus of this work was to evaluate the in vitro antiproliferative and antioxidant activity and the in vivo hypoglycaemic and anti-inflammatory activity of A. dioica and identify the principal constituents of this plant. Methods The crude methanol extract (EAD) and hexane (HF), chloroform (CF), ethyl acetate (EAF) and hydromethanol fractions (HMF) were evaluated for free radical scavenging activity using the DPPH assay. The EAD and EAF were assayed for hypoglycaemic activity in rats. The EAD was tested in an antiproliferation assay and for anti-inflammatory effects in paw oedema, in addition to myeloperoxidase activity induced by carrageenan (Cg) in mice. The EAF was assayed using chromatographic methods. Results The fractionation of the EAF through chromatographic methods identified derivatives of the flavonoids quercetin and kaempferol. Among all the tested fractions, the ethyl acetate and hydromethanol fractions were the most potent, exhibiting an IC50 of 8.53 and 10.57 μg/mL, respectively, which is comparable to that of the commercial antioxidant butylated hydroxytoluene (BHT). The oral administration of the EAD (100 mg/kg) and EAF (15 mg/kg) inhibited the increase of glucose levels, resulting in a hypoglycaemic effect. The EAD (30 to 300 mg/kg) exhibited an anti-oedematogenic effect in Cg-induced paw oedema in a time- and dose-dependent manner. The results showed a reduction of MPO activity by A. dioica 6 h after the induction of paw oedema at all doses tested with maximal inhibition at 300 mg/kg. Conclusions Our results reveal for the first time that compounds contained in the A. dioica leaves exert anti-inflammatory, hypoglycaemic, antiproliferative, and antioxidant effects. The antioxidant activity may be associated with the presence of flavonoids. PMID:23311341

  9. L-carnosine (beta-alanyl-L-histidine) and carcinine (beta-alanylhistamine) act as natural antioxidants with hydroxyl-radical-scavenging and lipid-peroxidase activities.

    PubMed Central

    Babizhayev, M A; Seguin, M C; Gueyne, J; Evstigneeva, R P; Ageyeva, E A; Zheltukhina, G A

    1994-01-01

    Carnosine (beta-alanyl-L-histidine) and carcinine (beta-alanylhistamine) are natural imidazole-containing compounds found in the non-protein fraction of mammalian tissues. Carcinine was synthesized by an original procedure and characterized. Both carnosine and carcinine (10-25 mM) are capable of inhibiting the catalysis of linoleic acid and phosphatidylcholine liposomal peroxidation (LPO) by the O2(-.)-dependent iron-ascorbate and lipid-peroxyl-radical-generating linoleic acid 13-monohydroperoxide (LOOH)-activated haemoglobin systems, as measured by thiobarbituric-acid-reactive substance. Carcinine and carnosine are good scavengers of OH. radicals, as detected by iron-dependent radical damage to the sugar deoxyribose. This suggests that carnosine and carcinine are able to scavenge free radicals or donate hydrogen ions. The iodometric, conjugated diene and t.l.c. assessments of lipid hydroperoxides (13-monohydroperoxide linoleic acid and phosphatidylcholine hydroperoxide) showed their efficient reduction and deactivation by carnosine and carcinine (10-25 mM) in the liberated and bound-to-artificial-bilayer states. This suggests that the peroxidase activity exceeded that susceptible to direct reduction with glutathione peroxidase. Imidazole, solutions of beta-alanine, or their mixtures with peptide moieties did not show antioxidant potential. Free L-histidine and especially histamine stimulated iron (II) salt-dependent LPO. Due to the combination of weak metal chelating (abolished by EDTA), OH. and lipid peroxyl radicals scavenging, reducing activities to liberated fatty acid and phospholipid hydroperoxides, carnosine and carcinine appear to be physiological antioxidants able to efficiently protect the lipid phase of biological membranes and aqueous environments. PMID:7998987

  10. Free radical scavenging and formation by multi-walled carbon nanotubes in cell free conditions and in human bronchial epithelial cells

    PubMed Central

    2014-01-01

    Background Certain multi-walled carbon nanotubes (MWCNTs) have been shown to elicit asbestos-like toxicological effects. To reduce needs for risk assessment it has been suggested that the physicochemical characteristics or reactivity of nanomaterials could be used to predict their hazard. Fibre-shape and ability to generate reactive oxygen species (ROS) are important indicators of high hazard materials. Asbestos is a known ROS generator, while MWCNTs may either produce or scavenge ROS. However, certain biomolecules, such as albumin – used as dispersants in nanomaterial preparation for toxicological testing in vivo and in vitro - may reduce the surface reactivity of nanomaterials. Methods Here, we investigated the effect of bovine serum albumin (BSA) and cell culture medium with and without BEAS 2B cells on radical formation/scavenging by five MWCNTs, Printex 90 carbon black, crocidolite asbestos, and glass wool, using electron spin resonance (ESR) spectroscopy and linked this to cytotoxic effects measured by trypan blue exclusion assay. In addition, the materials were characterized in the exposure medium (e.g. for hydrodynamic size-distribution and sedimentation rate). Results The test materials induced highly variable cytotoxic effects which could generally be related to the abundance and characteristics of agglomerates/aggregates and to the rate of sedimentation. All carbon nanomaterials were found to scavenge hydroxyl radicals (•OH) in at least one of the solutions tested. The effect of BSA was different among the materials. Two types of long, needle-like MWCNTs (average diameter >74 and 64.2 nm, average length 5.7 and 4.0 μm, respectively) induced, in addition to a scavenging effect, a dose-dependent formation of a unique, yet unidentified radical in both absence and presence of cells, which also coincided with cytotoxicity. Conclusions Culture medium and BSA affects scavenging/production of •OH by MWCNTs, Printex 90 carbon black, asbestos and glass

  11. Free radical scavenging abilities of flavonoids as mechanism of protection against mutagenicity induced by tert-butyl hydroperoxide or cumene hydroperoxide in Salmonella typhimurium TA102.

    PubMed

    Edenharder, R; Grünhage, D

    2003-09-01

    Mutagenicity induced by tert-butyl hydroperoxide (BHP) or cumene hydroperoxide (CHP) in Salmonella typhimurium TA102 was effectively reduced by flavonols with 3',4'-hydroxyl groups such as fisetin, quercetin, rutin, isoquercitrin, hyperoxide, myricetin, myricitrin, robinetin, and to a lesser extent also by morin and kaempferol (ID50=0.25-1.05 micromol per plate). With the exception of isorhamnetin, rhamnetin, morin, and kaempferol, closely similar results were obtained with both peroxides. Hydrogenation of the double bond between carbons 2 and 3 (dihydroquercetin, dihydrorobinetin) as well as the additional elimination of the carbonyl function at carbon 4 (catechins) resulted in a loss of antimutagenicity with the notable exception of catechin itself. Again, all flavones and flavanones tested were inactive except luteolin, luteolin-7-glucoside, diosmetin, and naringenin. The typical radical scavenger butylated hydroxytoluene also showed strong antimutagenicity against CHP (ID50=5.4 micromol per plate) and BHP (ID50=11.4 micromol per plate). Other lipophilic scavengers such as alpha-tocopherol and N,N'-diphenyl-1,4-phenylenediamine exerted only moderate effects, the hydrophilic scavenger trolox was inactive. The metal chelating agent 1,10-phenanthroline strongly reduced mutagenicities induced by CHP and BHP (ID50=2.75 and 2.5 micromol per plate) at low concentrations but induced mutagenic activities at higher concentrations. The iron chelator deferoxamine mesylate, however, was less effective in both respects. The copper chelator neocuproine effectively inhibited mutagenicity induced by BHP (ID50=39.7 micromol per plate) and CHP (ID50=25.9 micrommol per plate), the iron chelator 2,2'-dipyridyl was less potent (ID50=6.25 mmol per plate against BHP, 0.42 mmol per plate against CHP). In the absence of BHP and CHP, yet not in the presence of these hydroperoxides, quercetin, rutin, catechin, epicatechin, and naringenin induced strong mutagenic activities in S

  12. Mode of action of poly(vinylpyridine-N-oxide) in preventing silicosis: effective scavenging of carbonate anion radical.

    PubMed

    Goldstein, Sara; Czapski, Gideon; Heller, Adam

    2006-01-01

    Small particles of crystalline silicon dioxide (crystallites) are exceptionally toxic. Inhalation of quartz crystallites causes silicosis, a devastating lung disease afflicting miners, particularly coal and stone workers. Poly(vinylpyridine-N-oxide)s (PVPNOs) have been applied in the prevention and treatment of silicosis, but their mode of action has been obscure. Recently, the sites of inducible *NO synthase activation and of nitrotyrosine formation were associated anatomically with the pathological quartz particle-caused lesions in the lungs. It has been suggested that the *NO formed combines rapidly with O2*- to yield ONOO-, a potential mediator of lung injury following silica exposure. Here, we show that PVPNOs do not react with peroxynitrite but scavenge exceptionally rapidly CO3*- radicals, which are produced in the decomposition of ONOO- in bicarbonate solutions. The rate constant for the reaction of CO3*- with PVPNO was found to be independent of the type and size of PVPNO, i.e., k = (1.9 +/- 0.2) x 10(5) M(-1) s(-1) per monomer. In contrast, the rate constant for the reaction of CO3*- with the small molecule 4-methylpyridine N-oxide did not exceed 1 x 10(4) M(-1) s(-1). The underlying reason for the difference is that, in the dissolved polymeric PVPNOs, the electrostatic repulsion between the N-oxide zwitterions destabilizes them, increasing dramatically their pKa. The protonated N-oxides at physiological pH have abstractable hydrogen atoms and are expected to react rapidly with CO3*-, just as cyclic hydroxylamines do. It is also shown that PVPNO inhibits tyrosine nitration by peroxynitrite at pH 7.6 in the presence of excess of CO2 in a concentration-dependent manner. Hence, binding of PVPNO to the quartz particles and eliminating CO3*- could prevent the killing of macrophages, the associated release of macrophage-recruiting cytokines, and the amplification of the local concentration of *NO by the recruited macrophages. The latter causes necrosis of the

  13. An evaluation of extracts of five traditional medicinal plants from Iran on the inhibition of mushroom tyrosinase activity and scavenging of free radicals.

    PubMed

    Khazaeli, P; Goldoozian, R; Sharififar, F

    2009-10-01

    This study aimed to evaluate the free radical scavenging and inhibition properties of five medicinal plants, including Quercus infectoria Olive., Terminalia chebula Retz., Lavendula stoechas L., Mentha longifolia L., Rheum palmatum L., toward the activity of mushroom tyrosinase using L-tyrosine and L-3,4-dihydroxyphenylalanine (L-DOPA) as the substrate.The methanol extracts of Q. infectoria and T. chebula showed strong radical scavenging effect in 2,2'-dipheny L-1-picrylhydrazyl (DPPH) assay(IC50 = 15.3 and 82.2 microg mL)1 respectively).These plants also showed inhibitory effects against the activity of mushroom tyrosinase in hydroxylation of L-tyrosine (85.9% and 82.2% inhibition,respectively). These two plants also inhibited the oxidation of l-DOPA similar to kojic acid as positive control (IC50 = 102.8 and 192.6 microg mL)1 respectively). In general Q. infectoria and T. chebula significantly inhibited tyrosinase activity and DPPH radical. Both activities were concentration dependant but not in linear manner. It is needed to study the cytotoxicity of these plant extracts in pigment cell culture before further evaluation and moving to in vivo conditions. PMID:19467035

  14. An on-line normal-phase high performance liquid chromatography method for the rapid detection of radical scavengers in non-polar food matrixes.

    PubMed

    Zhang, Qiang; van der Klift, Elbert J C; Janssen, Hans-Gerd; van Beek, Teris A

    2009-10-23

    An on-line method for the rapid pinpointing of radical scavengers in non-polar mixtures like vegetable oils was developed. To avoid problems with dissolving the sample, normal-phase chromatography on bare silica gel was used with mixtures of hexane and methyl tert-butyl ether as the eluent. The high performance liquid chromatography-separated analytes are mixed post-column with a solution of stable free radicals in hexane. Reduced levels of the radical as a result of a reaction with a radical scavenger are detected as negative peaks by an absorbance detector. After investigating a number of different reagents, solvents, concentrations and solution flow rates an optimized instrumental set-up incorporating a superloop for pulse-free delivery of the reagent solution is presented. Both 2,2'-diphenyl-1-picrylhydrazyl (DPPH) and 2,6-di-tert-butyl-alpha-(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadien-1-ylidene)-p-tolyloxy (galvinoxyl) were used as stable free radicals. The method is suitable for both isocratic and gradient HPLC operation. The method has a simple experimental protocol, uses standard instruments and inexpensive and stable reagents, and accepts any hexane-soluble sample. It can also be used for semi-quantitative analysis. The method was applied to several pure, non-polar natural antioxidants, vegetable oils and lipid-soluble rosemary extract. The limits of detection varied from 0.2 to 176 microg/ml, depending on the compound tested. PMID:19726044

  15. DNA strand break dependence on Tris and arginine scavenger concentrations under ultra-soft X-ray irradiation: the contribution of secondary arginine radicals.

    PubMed

    Souici, Mounir; Khalil, Talat Tariq; Boulanouar, Omar; Belafrites, Abdelfettah; Mavon, Christophe; Fromm, Michel

    2016-05-01

    In this study, we used a bench-top cold-cathode ultra-soft X-ray (USX) generator to expose aqueous DNA plasmid solutions to low-LET radiation under various scavenging conditions. Single- and double-strand breaks were assessed using classic gel electrophoresis quantification of linear, circular and supercoiled plasmid DNA topologies. With their very low penetration range in water, USX can only interact with matter up to short distances, of the order of 50 μm. We validated a stirring procedure which makes it possible to expose 100 µL of aqueous samples (2 mm thick). The scavenging of OH radicals by Tris buffer was studied at ambient temperature under aerobic conditions and compared to data gathered in the literature. A very good agreement was found with the rare data dealing with DNA plasmid exposed to Al Kα photons at low temperature (T ≤ 277 K), which therefore validated the experimental procedure. The yields for DNA single-strand breaks determined during this study enabled the ratio of indirect to direct effects to be determined at 96.2%, in good agreement with the value of 97.7% stemming from a study based on γ-ray irradiation of frozen solutions of plasmid DNA. Then, arginine was used both to create a "biological-like" chemical environment around the DNA plasmids and as an OH radical scavenger, in vitro. Although arginine has a greater scavenging (protecting) power than Tris, surprisingly, it led to higher rates of strand breakage. Based on the specific binding modes of arginine to DNA, we suggest that the side effects observed are due to the presence of arginine near to, but also inside, the DNA double helix. PMID:26994994

  16. Effect of gamma sterilization on microhardness of the cortical bone tissue of bovine femur in presence of N-Acetyl-L-Cysteine free radical scavenger.

    PubMed

    Allaveisi, Farzaneh; Hashemi, Bijan; Mortazavi, Seyed Mohammad Javad

    2014-05-01

    Gamma sterilization is usually used to minimize the risk of infection transmission through bone allografts. However, it is believed that gamma irradiation affects the mechanical properties of allografts and free radical scavengers can be used to alleviate the radiation-induced degradation of these properties. The aim of this study was to investigate the radioprotective effects of N-Acetyl-L-Cysteine (NAC) free radical scavenger on the material properties of sterilized bovine cortical bone at microstructure level. Forty-two cortical tissue specimens were excised from three bovine femurs and irradiated to 35 and 70 kGy gamma rays in the presence of 5, 50, and 100 mM concentrations of NAC. The localized variations in microhardness were evaluated via indentation in the radial and longitudinal directions to examine different regions of the microstructures of the specimens, including the osteonal and interstitial tissues. A significant increase was observed in the hardness of osteonal, interstitial, and longitudinal combined microstructures exposed to 35 and 70 kGy radiations (P < 0.05), whereas a relative reduction of the hardness was observed in the radial direction. Furthermore, it was found that the application of 50 and 100 mM NAC during gamma irradiation significantly subsided the hardening in longitudinal combined microstructure. Moreover, the reduction of hardness in radial direction was suppressed in the presence of 100 mM of NAC. In conclusion, the results indicated that NAC free radical scavenger can protect the cortical bone against deteriorative effects of ionizing radiation and can be used to improve the material properties of sterilized allografts. PMID:24119926

  17. A radical scavenger edaravone inhibits matrix metalloproteinase-9 upregulation and blood-brain barrier breakdown in a mouse model of prolonged cerebral hypoperfusion

    PubMed Central

    Maki, Takakuni; Liang, Anna C.; Arai, Ken

    2014-01-01

    Matrix metalloproteinase-9 (MMP-9) plays key roles in the brain pathophysiology, especially in blood-brain barrier (BBB) breakdown. Therefore, inhibiting MMP-9 activity may be a promising therapy for protecting brains in cerebrovascular diseases. Here we show that in a mouse prolonged cerebral hypoperfusion model, a clinically proven radical scavenger edaravone suppressed MMP-9 and reduced BBB damage in cerebral white matter. Prolonged cerebral hypoperfusion was induced by bilateral common carotid artery stenosis in male adult C57BL/6J mice (10 weeks old). After 7 days of cerebral hypoperfusion, white matter region (e.g. corpus callosum) exhibited significant BBB leakage, assessed by IgG staining. Correspondingly, immunostaining and western blotting showed that MMP-9 was upregulated in the white matter. Edaravone treatment (3 mg/kg, i.p. at day 0 and 3) inhibited both BBB leakage and MMP-9 increase. Under the early phase of cerebral hypoperfusion conditions, oligodendrocyte precursor cells (OPCs) mainly contribute to the MMP-9 increase, but our immunostaining data showed that very little OPCs expressed MMP-9 in the edaravone-treated animals at day 7. Therefore, in vitro studies with primary rat OPCs were conducted to examine whether edaravone would directly suppressed MMP-9 expressions in OPCs. OPC cultures were exposed to sub-lethal CoCl2 for 7 days to induce prolonged chemical hypoxic stress. Prolonged chemical hypoxic stress increased MMP-9 expression in OPCs, and radical scavenging with edaravone (10 μM for 7 days) ameliorated the increase. Taken together, our proof-of-concept study demonstrates that radical scavengers may provide a potential therapeutic approach for white matter injury by suppressing BBB damage. PMID:24820542

  18. Theoretical Determination of the pK a Values of Betalamic Acid Related to the Free Radical Scavenger Capacity: Comparison Between Empirical and Quantum Chemical Methods.

    PubMed

    Tutone, Marco; Lauria, Antonino; Almerico, Anna Maria

    2016-06-01

    Health benefits of dietary phytochemicals have been suggested in recent years. Among 1000s of different compounds, Betalains, which occur in vegetables of the Cariophyllalae order (cactus pear fruits and red beet), have been considered because of reducing power and potential to affect redox-modulated cellular processes. The antioxidant power of Betalains is strictly due to the dissociation rate of the acid moieties present in all the molecules of this family of phytochemicals. Experimentally, only the pK a values of betanin were determined. Recently, it was evidenced it was evidenced as the acid dissociation, at different environmental pHs, affects on its electron-donating capacity, and further on its free radical scavenging power. The identical correlation was studied on another Betalains family compound, Betalamic Acid. Experimental evidences showed that the free radical scavenging capacity of this compound drastically decreases at pH > 5, but pK a values were experimentally not measured. With the aim to justify the Betalamic Acid behavior as free radical scavenger, in this paper we tried to predict in silico the pK a values by means different approaches. Starting from the known experimental pK as of acid compounds, both phytochemicals and small organic, two empirical approaches and quantum-mechanical calculation were compared to give reliable prediction of the pK as of Betalamic Acid. Results by means these computational approaches are consistent with the experimental evidences. As shown herein, in silico, the totally dissociated species, at the experimental pH > 5 in solution, is predominant, exploiting the higher electron-donating capability (HOMO energy). Therefore, the computational estimated pK a values of Betalamic Acid resulted very reliable. PMID:26253717

  19. Self-catalyzed syntheses, structural characterization, DPPH radical scavenging-, cytotoxicity-, and DFT studies of phenoxyaliphatic acids of 1,8-dioxo-octahydroxanthene derivatives

    NASA Astrophysics Data System (ADS)

    Suresh Kumar, G. S.; Antony Muthu Prabhu, A.; Seethalashmi, P. G.; Bhuvanesh, N.; Kumaresan, S.

    2014-02-01

    One-pot, in-water syntheses of phenoxyaliphatic acids of 1,8-dioxo-octahydroxanthene derived from dimedone and formylphenoxyaliphatic acids are reported. Geometries of compounds 2b, 2c, and 5a have been examined crystallographically. The synthesized compounds showed better DPPH radical scavenging activity and cytotoxicity against A431 cancer cell line. The molecular properties of all synthesized xanthenes have been investigated using single crystal XRD and DFT method. Self-catalyzed Bronsted-Lowry acid catalytic behavior was also investigated by both experimental and theoretical methods.

  20. Carbohydrase inhibition and anti-cancerous and free radical scavenging properties along with DNA and protein protection ability of methanolic root extracts of Rumex crispus

    PubMed Central

    Shiwani, Supriya; Singh, Naresh Kumar

    2012-01-01

    The study elucidated carbohydrase inhibition, anti-cancerous, free radical scavenging properties and also investigated the DNA and protein protection abilities of methanolic root extract of Rumex crispus (RERC). For this purpose, pulverized roots of Rumex crispus was extracted in methanol (80% and absolute conc.) for 3 hrs for 60℃ and filtered and evaporated with vacuum rotary evaporator. RERC showed high phenolic content (211 µg/GAE equivalent) and strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging (IC50 = 42.86 (absolute methanol) and 36.91 µg/mL (80% methanolic extract)) and reduced power ability. Furthermore, RERC exhibited significant protective ability in H2O2/Fe3+/ascorbic acid-induced protein or DNA damage and percentage inhibition of the HT-29 cell growth rate following 80% methanolic RERC exposure at 400 µg/mL was observed to be highest (10.2% ± 1.03). Moreover, methanolic RERC inhibited α-glucosidase and amylase effectively and significantly (P < 0.05). Conclusively, RERC could be considered as potent carbohydrase inhibitor, anti-cancerous and anti-oxidant. PMID:23198017

  1. Antiviral, immunomodulatory, and free radical scavenging activities of a protein-enriched fraction from the larvae of the housefly, Musca domestica.

    PubMed

    Ai, Hui; Wang, Furong; Zhang, Na; Zhang, Lingyao; Lei, Chaoliang

    2013-01-01

    In our previous study, protein-enriched fraction (PEF) that was isolated from the larvae of the housefly, Musca domestica L. (Diptera: Muscidae), showed excellent hepatoprotective activity as well as the potential for clinical application in therapy for liver diseases. In this study, antiviral, immunomodulatory, and free radical scavenging activities of PEF were evaluated. The antiviral results demonstrated that PEF inhibited the infection of avian influenza virus H9N2 and had a virucidal effect against the multicapsid nucleopolyhedrovirus of the alfalfa looper, Autographa californica Speyer (Lepidoptera: Noctuidae) in vitro. The mortality of silkworm larve in a PEF treatment group decreased significantly compared with a negative control. PEF showed excellent scavenging activity for 1,1-diphenyl-2-picrylhydrazyl and superoxide anion radicals, which were similar to those of ascorbic acid. The imunomodulatory results suggested that PEF could effectively improve immune function in experimental mice. Our results indicated that PEF could possibly be used for the prophylaxis and treatment of diseases caused by avian influenza virus infection. In addition, PEF with virucidal activity against insect viruses might provide useful for the development of antimicrobial breeding technology for economically important insects. As a natural product from insects, PEF could be a potential source for the discovery of potent antioxidant and immunomodulatory agents. PMID:24735244

  2. Crystal structure, DFT and HF calculations and radical scavenging activities of (E)-4,6-dibromo-3-methoxy-2-[(3-methoxyphenylimino)methyl]phenol

    NASA Astrophysics Data System (ADS)

    Alaşalvar, Can; Soylu, Mustafa Serkan; Güder, Aytaç; Albayrak, Çiğdem; Apaydın, Gökhan; Dilek, Nefise

    In this study, (E)-4,6-dibromo-3-methoxy-2-[(3-methoxyphenylimino)methyl]phenol has been synthesized and characterized by using X-ray technique and FT-IR experimentally and using B3LYP/6-31G(d,p) and HF/6-31G(d,p) methods theoretically. The intermolecular and intramolecular interactions of the title compound have been determined according to X-ray results. The molecular geometry, vibrational frequencies of the title compound in the ground state have been calculated using the density functional B3LYP and HF method with the 6-31G(d,p) basis set and calculated bond parameters and vibrational frequencies values show good agreement with experimental values. Theoretical and experimental results show that tautomeric form of the structure is phenol-imine form. Besides HOMO-LUMO energy gap, molecular electrostatic potential map were performed at B3LYP/6-31G(d,p) level. It is worthy note of that, the free radical scavenging activities of the title compound were assessed using DPPHrad , DMPDrad +, and ABTSrad + assays. The obtained results show that the title compound has effective DPPHrad (SC50 2.61 ± 0.09 μg/mL), DMPDrad + (SC50 2.82 ± 0.14 μg/mL), and ABTSrad + (SC50 4.91 ± 0.18 μg/mL) radical scavenging activities when compared with standard antioxidants (BHA, rutin, and trolox).

  3. Effects of Comb Tooth Cap Medicinal Mushroom, Hericium ramosum (Higher Basidiomycetes) Mycelia on DPPH Radical Scavenging Activity and Nerve Growth Factor Synthesis.

    PubMed

    Suruga, Kohei; Kadokura, Kazunari; Sekino, Yoshihiro; Nakano, Takafumi; Matsuo, Koichi; Irie, Keiichi; Mishima, Kenichi; Yoneyama, Makoto; Komatsu, Yasuhiro

    2015-01-01

    The goal of this study was to evaluate the antioxidant effects of and nerve growth factor (NGF) synthesis caused by Hericium ramosum mycelia. Wild mushroom fruiting bodies were collected from nature to isolate their mycelia. Pieces of H. ramosum fruiting bodies were plated onto 90-mm Petri dishes with potato dextrose agar medium to isolate their mycelia. Antioxidant activity was measured using 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging activity in vitro; the ethanol extract from H. ramosum mycelia (63.11 µmol Trolox/g) was more potent than that of other mushroom mycelia extracts. There was a proportional relationship (R2 = 0.7929) between DPPH radical scavenging activity and total phenolic content in extracts of different mushroom mycelia. We investigated the ability of H. ramosum mycelia to inducing NGF synthesis in vivo. Oral administration of H. ramosum mycelia significantly increased concentrations of NGF in the hippocampus of intact mice. These results are the first concerning antioxidant activity and NGF synthesis of H. ramosum mycelia. These mushroom mycelia could be useful as food and/or nutritional supplements because of certain biological functions. PMID:25954959

  4. Antiviral, Immunomodulatory, and Free Radical Scavenging Activities of a Protein-Enriched Fraction from the Larvae of the Housefly, Musca domestica

    PubMed Central

    Ai, Hui; Wang, Furong; Zhang, Na; Zhang, Lingyao; Lei, Chaoliang

    2013-01-01

    In our previous study, protein-enriched fraction (PEF) that was isolated from the larvae of the housefly, Musca domestica L. (Diptera: Muscidae), showed excellent hepatoprotective activity as well as the potential for clinical application in therapy for liver diseases. In this study, antiviral, immunomodulatory, and free radical scavenging activities of PEF were evaluated. The antiviral results demonstrated that PEF inhibited the infection of avian influenza virus H9N2 and had a virucidal effect against the multicapsid nucleopolyhedrovirus of the alfalfa looper, Autographa californica Speyer (Lepidoptera: Noctuidae) in vitro. The mortality of silkworm larve in a PEF treatment group decreased significantly compared with a negative control. PEF showed excellent scavenging activity for 1,1-diphenyl-2-picrylhydrazyl and superoxide anion radicals, which were similar to those of ascorbic acid. The imunomodulatory results suggested that PEF could effectively improve immune function in experimental mice. Our results indicated that PEF could possibly be used for the prophylaxis and treatment of diseases caused by avian influenza virus infection. In addition, PEF with virucidal activity against insect viruses might provide useful for the development of antimicrobial breeding technology for economically important insects. As a natural product from insects, PEF could be a potential source for the discovery of potent antioxidant and immunomodulatory agents. PMID:24735244

  5. Studies on cytotoxic, hydroxyl radical scavenging and topoisomerase inhibitory activities of extracts of Tabernaemontana divaricata (L.) R.Br. ex Roem. and Schult.

    PubMed

    Thind, Tarunpreet Singh; Agrawal, Satyam Kumar; Saxena, A K; Arora, Saroj

    2008-08-01

    In the present investigation, the cytotoxic, hydroxyl radical scavenging and topoisomerase inhibition activities of Tabernaemontana divaricata (Apocynaceae) were evaluated. The extracts from leaves of the plant were prepared with different solvents viz. chloroform, methanol, ethyl acetate and hexane. In, in vitro cytotoxicity assay, with cell lines viz HCT-15 (Colon), HT-29 (Colon), 502713 (Colon), MCF-7 (Breast), PC- 3 (Prostrate), it was observed that the ethyl acetate extract was effective against only one colon cell line (502713) at the lowest dose i.e. 10 micro g/ml, whereas the chloroform extract was effective against all the three colon cancer cell lines, at 30 microg/ ml. In order to evaluate the mechanism of cytotoxicity of these extracts, they were assessed for their ability to scavenge hydroxyl radicals in plasmid nicking assay with pBR322. It was observed that all the extracts effectively inhibited the unwinding of supercoiled DNA except hexane extract, which showed the least effect. Since the expression of topo enzymes is linked with cell proliferation so the extracts were also checked for topo I and topo II inhibitory activities. It was noticed that ethyl acetate extract selectively showed inhibition of topo II in topoisomerase II relaxation assay. PMID:18577413

  6. Free radicals scavenging action and anti-enzyme activities of procyanidines from Vitis vinifera. A mechanism for their capillary protective action.

    PubMed

    Maffei Facino, R; Carini, M; Aldini, G; Bombardelli, E; Morazzoni, P; Morelli, R

    1994-05-01

    The scavenging by procyanidines (polyphenol oligomers from Vitis vinifera seeds, CAS 85594-37-2) of reactive oxygen species (ROS) involved in the onset (HO degrees) and the maintenance of microvascular injury (lipid radicals R degrees, RO degrees, ROO degrees) has been studied in phosphatidylcholine liposomes (PCL), using two different models of free radical generation: a) iron-promoted and b) ultrasound-induced lipid peroxidation. In a) lipid peroxidation was assessed by determination of thiobarbituric acid-reactive substances (TBARS); in b) by determination of conjugated dienes, formation of breakdown carbonyl products (as 2,4-dinitrophenylhydrazones) and loss of native phosphatidylcholine. In the iron-promoted (Fenton-driven) model, procyanidines had a remarkable, dose-dependent antilipoperoxidant activity (IC50 = 2.5 mumol/l), more than one order of magnitude greater than that of the monomeric unit catechin (IC50 = 50 mumol/l), activity which is due, at least in part, to their metal-chelating properties. In the more specific model b), which discriminates between the initiator (hydroxyl radical from water sonolysis) and the propagator species of lipid peroxidation (the peroxyl radical, from autooxidation of C-centered radicals), procyanidines are highly effective in preventing conjugated diene formation in both the induction (IC50 = 0.1 mumol/l) and propagation (IC50 = 0.05 mumol/l) phases (the scavenging effect of alpha-tocopherol was weaker, with IC50 of 1.5 and 1.25 mumol/l). In addition, procyanidines at 0.5 mumol/l markedly delayed the onset of the breakdown phase (48 h), totally inhibiting during this time the formation of degradation products (the lag-time induced by alpha-tocopherol was only of 24 h at 10 mumol/l concentration). The HO degrees entrapping capacity of these compounds was further confirmed by UV studies and by electron spin resonance (ESR) spectroscopy, using DMPO as spin trapper: procyanidines markedly reduced, in a dose-dependent fashion

  7. Effect of gamma irradiation on the microbial load, nutrient composition and free radical scavenging activity of Nelumbo nucifera rhizome

    NASA Astrophysics Data System (ADS)

    Khattak, Khanzadi Fatima; Simpson, Thomas James; Ihasnullah

    2009-03-01

    The assurance of microbial quality is necessary to make plant materials suitable for human consumption and commercialization. The aim of the present study was to evaluate the possibility to apply the gamma radiation treatment on the rhizome samples of Nelumbo nucifera for microbial decontamination. The radiation processing was carried out at dose levels of 1, 2, 4 and 6 kGy. The irradiated and control samples were analyzed for microbial load, organoleptic acceptance, extraction yield, proximate composition, phenolic contents and DPPH scavenging activity. The results indicated that gamma radiation treatment significantly reduced microbial load and increased the storability of the irradiated samples. The treated samples were also acceptable sensorically. The extraction yield and phenolic contents increased with the increase of radiation dose. Gamma radiation also enhanced the DPPH scavenging activity.

  8. Bioguided fractionation and isolation of free radical scavenging components from in vitro propagated chinese medicinal plants Dendrobium tosaense Makino and Dendrobium moniliforme SW.

    PubMed

    Lo, Shu-Fung; Mulabagal, Vanisree; Chen, Chung-Li; Kuo, Chao-Lin; Tsay, Hsin-Sheng

    2004-11-17

    This study was performed to investigate the free radical scavenging active components from in vitro propagated medicinal herbs of the genus Dendrobium, namely, Dendrobium tosaense Makino and Dendrobium moniliforme SW, using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical antioxidative assay. Seeds of the capsules derived after 12 weeks of hand-pollination germinated asymbiotically (50-74%) on half-strength Murashige and Skoog's (MS) basal medium with 3% sucrose and solidified with 0.9% Difco agar. Active growth in the germinated seedlings was achieved by reculturing on full-strength MS basal medium supplemented with 8% banana homogenate, 8% potato homogenate, 8% coconut water, 1.5% sucrose, and 0.9% Difco agar. Healthy plantlets transferred to plastic trays containing moss or moss and tree fern successfully acclimatized (84-100%) in the greenhouse. Extracts were prepared from plants grown in the greenhouse for a period of 6 months. Methanolic extracts of D. tosaense and D. moniliforme scavenged DPPH at 95.9 and 83.4%, respectively, at a concentration of 0.4 mg/mL. Therefore, methanolic solubles of D. tosaense and D. moniliforme were subjected to bioguided fractionation and separation by column chromatographic methods individually. After chromatographic separation of these crude extracts, the obtained fractions (Dm 1, Dm 2, Dm 3, Dt 1, Dt 2, and Dt 3) were tested for their activity. Among them, fractions Dm 2 and Dt 1 showed significant antioxidant activity by DPPH radical antioxidative assay. Active fractions were purified further by column chromatography and resulted in identification of the antioxidant components alkyl ferulates from D. moniliforme and quercetin from D. tosaense. PMID:15537296

  9. Free Radical Scavenging Fingerprints of Selected Aromatic and Medicinal Tunisian Plants Assessed by Means of TLC-DPPH(•) Test and Image Processing.

    PubMed

    El Euch, Salma Kammoun; Cieśla, Łukasz; Bouzouita, Nabiha

    2014-01-01

    Aqueous-methanol extracts prepared from 10 Tunisian plant species were analyzed for the presence of potent direct antioxidants. The analyzed species included: Anacyclus clavatus Desf., Erica multiflora L., Cistus salvifolius L., Centaurium erythraea Rafn., Marrubium vulgare L., Lavandula stoechas L., Artemisia campestris L., Origanum majorana L., Salvia officinalis L., and Pistacia lentiscus L. All the extracts were chromatographed on the RP18 W plates with methanol-water-acetic acid (48 + 47 + 5, v/v/v) mobile phase. Upon completion of the chromatographic development and the drying step, the plates were stained with a chloroform solution of 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH(•)). An image processing protocol, with use of Sorbfil TLC Videodensitometer, was applied to quantitatively measure the activity of polyphenols and to screen complex samples for the presence of free radical scavengers. The activity of the individual compounds was compared with that of rutin, used as a standard. The TLC-DPPH(•) test showed that C. salvifolius had the most potent antioxidant activity, as it possessed the highest activity coefficient (calculated as the sum of the areas under the peaks of all active compounds/area under peak of rutin). The proposed procedure may be used to differentiate potent chain-breaking antioxidants and compounds propagating radical chain reactions. PMID:25902978

  10. Assessment of the Polyphenolic Content, Free Radical Scavenging, Anti-inflammatory, and Antimicrobial Activities of Acetone and Aqueous Extracts of Lippia javanica (Burm.F.) Spreng

    PubMed Central

    Asowata-Ayodele, Abiola M.; Otunola, Gloria A.; Afolayan, Anthony J.

    2016-01-01

    Background: Lippia javanica (Burm.F.) Spreng is one of the spice plants commonly found in almost every part of South Africa. Apart from its culinary uses, it is also traditionally used as an insect repellant and infusion for fever, flu, kidney stone treatment, cough, common cold, and chest pain. Materials and Methods: The antioxidant activities of the aqueous and acetone extracts were determined by measuring their effects against 1,1-Diphenyl-2-picryl-hydrazyl, 2,2’azino-bis (3-ethylbenzthiazoline-6-sulfonic acid), nitric oxide, phosphomolybdate, lipid peroxidation, hydrogen peroxide, and reducing power. The antimicrobial activities were evaluated against four bacterial (two Gram-positive, two Gram-negative) strains and 9 fungal pathogens using the agar well diffusion and microdilution methods. Anti-inflammatory activity was assessed by determining the inhibition against protein denaturation and membrane stabilizing effects. Objective: The polyphenolic content, free radical scavenging, anti-inflammatory, and antimicrobial activities of the aqueous and acetone extracts of the plant were evaluated. Results: A significantly high total phenolic content and free radical scavenging activities were observed in the acetone extracts of the plants. The study also revealed a concentration-dependent inhibition of protein denaturation and membrane stabilization effects by both the aqueous and acetone extracts at the concentrations studied. The ability of L. javanica extracts to inhibit protein denaturation and maintain membrane stability could be responsible for its folkloric use. The overall antimicrobial activity indicates that both extracts were active against the bacterial strains but the acetone extract exhibited the most potent antifungal activity higher than even the reference drugs. Conclusion: Overall, the acetone extract of L. javanica exhibited a more pronounced antioxidant, anti-inflammatory, and antimicrobial effects than the aqueous extract. SUMMARY The

  11. Assessment of Free Radical Scavenging Activity of Dimethylglycine Sodium Salt and Its Role in Providing Protection against Lipopolysaccharide-Induced Oxidative Stress in Mice.

    PubMed

    Bai, Kaiwen; Xu, Wen; Zhang, Jingfei; Kou, Tao; Niu, Yu; Wan, Xiaoli; Zhang, Lili; Wang, Chao; Wang, Tian

    2016-01-01

    In the present study, the free radical scavenging activities (against 1,1-diphenyl-2-pierylhydrazy (DPPH), 2,2'-Azinobis-(3-ethylbenzthiazoline-6- sulphonate) (ABTS+), Hydrogen peroxide (H2O2)) of dimethylglycine sodium salt (DMG-Na) were measured and compared with those of Trolox (6-hydroxy-2, 5, 7, 8-tetramethylchroman-2-carboxylic acid), a commonly used antioxidant. The radical scavenging activities of DMG-Na were found to be the highest at 40 mg/ml. In Experiment 2, gastric intubation in mice with 12 mg DMG-Na/0.3 ml sterile saline solution significantly increased (P < 0.05) the body weight (BW) (28 d), organ proportion (liver and spleen), and antioxidant capacity in serum and the liver (Superoxide dismutase (SOD), Hydrogen peroxidase (CAT), Glutathione peroxidase (GPx), and Total antioxidant capacity (T-AOC)), and significantly decreased (P < 0.05) the activities of serum Glutamic-pyruvic transaminase (ALT) and Glutamic oxalacetic transaminase (AST) and Methane Dicarboxylic Aldehyde (MDA) contents in the serum and liver. Specifically, the effect of 12 mg DMG-Na/0.3 ml sterile saline solution, which showed the highest antioxidant capacity, was further studied using a mice model. In Experiment 3, the mice CL (CON+ lipopolysaccharide (LPS)) group showed a significant decrease (P < 0.05) in the serum ALT and AST content; hepatic mitochondrial antioxidant capacity (Manganese Superoxide dismutase (MnSOD), Glutathione reductase (GR), GPx, Glutathione (GSH)); MDA and Protein carbonyl (PC) content; Reactive oxygen species (ROS) level, Mitochondrial membrane potential (MMP) level, and expression of liver antioxidant genes (Nuclear factor erythroid 2-related factor 2 (Nrf2), Heme oxygenase 1 (HO-1), Manganese superoxide dismutase (MnSOD), Glutathione peroxidase 1 (Gpx1), Sirtuin 1 (Sirt1)) relative to the mice CS (CON+ sterile saline) group. The DL (DMG+LPS) group showed a significant decrease (P < 0.05) in serum ALT and AST content, ROS level, and expression of liver

  12. Assessment of Free Radical Scavenging Activity of Dimethylglycine Sodium Salt and Its Role in Providing Protection against Lipopolysaccharide-Induced Oxidative Stress in Mice

    PubMed Central

    Zhang, Jingfei; Kou, Tao; Niu, Yu; Wan, Xiaoli; Zhang, Lili; Wang, Chao; Wang, Tian

    2016-01-01

    In the present study, the free radical scavenging activities (against 1,1-diphenyl-2-pierylhydrazy (DPPH), 2,2'-Azinobis-(3-ethylbenzthiazoline-6- sulphonate) (ABTS+), Hydrogen peroxide (H2O2)) of dimethylglycine sodium salt (DMG-Na) were measured and compared with those of Trolox (6-hydroxy-2, 5, 7, 8-tetramethylchroman-2-carboxylic acid), a commonly used antioxidant. The radical scavenging activities of DMG-Na were found to be the highest at 40 mg/ml. In Experiment 2, gastric intubation in mice with 12 mg DMG-Na/0.3 ml sterile saline solution significantly increased (P < 0.05) the body weight (BW) (28 d), organ proportion (liver and spleen), and antioxidant capacity in serum and the liver (Superoxide dismutase (SOD), Hydrogen peroxidase (CAT), Glutathione peroxidase (GPx), and Total antioxidant capacity (T-AOC)), and significantly decreased (P < 0.05) the activities of serum Glutamic-pyruvic transaminase (ALT) and Glutamic oxalacetic transaminase (AST) and Methane Dicarboxylic Aldehyde (MDA) contents in the serum and liver. Specifically, the effect of 12 mg DMG-Na/0.3 ml sterile saline solution, which showed the highest antioxidant capacity, was further studied using a mice model. In Experiment 3, the mice CL (CON+ lipopolysaccharide (LPS)) group showed a significant decrease (P < 0.05) in the serum ALT and AST content; hepatic mitochondrial antioxidant capacity (Manganese Superoxide dismutase (MnSOD), Glutathione reductase (GR), GPx, Glutathione (GSH)); MDA and Protein carbonyl (PC) content; Reactive oxygen species (ROS) level, Mitochondrial membrane potential (MMP) level, and expression of liver antioxidant genes (Nuclear factor erythroid 2-related factor 2 (Nrf2), Heme oxygenase 1 (HO-1), Manganese superoxide dismutase (MnSOD), Glutathione peroxidase 1 (Gpx1), Sirtuin 1 (Sirt1)) relative to the mice CS (CON+ sterile saline) group. The DL (DMG+LPS) group showed a significant decrease (P < 0.05) in serum ALT and AST content, ROS level, and expression of liver

  13. Solubilisation of a 2,2-diphenyl-1-picrylhydrazyl radical in water by β-cyclodextrin to evaluate the radical-scavenging activity of antioxidants in aqueous media.

    PubMed

    Nakanishi, Ikuo; Ohkubo, Kei; Imai, Kohei; Kamibayashi, Masato; Yoshihashi, Yasuo; Matsumoto, Ken-ichiro; Fukuhara, Kiyoshi; Terada, Katsuhide; Itoh, Shinobu; Ozawa, Toshihiko; Fukuzumi, Shunichi

    2015-05-14

    A 2,2-diphenyl-1-picrylhydrazyl radical (DPPH˙) was successfully solubilised in water by β-cyclodextrin (β-CD). DPPH˙/β-CD thus obtained was demonstrated to be a powerful tool to evaluate the antioxidative activity of water-soluble antioxidants, such as ascorbate and Trolox, in aqueous buffer solutions. PMID:25877460

  14. Spectroscopic and computational study of the major oxidation products formed during the reaction of two quercetin conformers with a free radical

    NASA Astrophysics Data System (ADS)

    Mendoza-Wilson, Ana María; Santacruz-Ortega, Hisila; Balandrán-Quintana, René R.

    2011-10-01

    The goal of this research was to determine whether there are differences between the major oxidation products formed during the reaction of quercetin unhydrate (QUH) or quercetin dihydrate (QDH) with the 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH rad ), as well as to identify some properties of these products. The study was carried out employing spectroscopic and computational methods, in order to know the effect of different conformations of quercetin on the mechanism of free radical scavenging. The results demonstrated that although the same oxidation products may be formed from QUH and QDH, their properties and the predominant product were different in each. The o-quinone was the predominant oxidation product of QUH, whereas in QDH it was established an equilibrium between o-quinone and extended p-quinone.

  15. A study on the activities of a few free radicals scavenging enzymes present in five roadside plants.

    PubMed

    Mandal, M; Mukherji, S

    2001-10-01

    The road side plants are continuously exposed to the high levels of oxides of nitrogen and sulphur dioxide, emitted from automobile. Resistance to automobile exhaust pollution was studied with Nerium indicum Mill, Boerhaavia diffusa L., Amaranthus spinosus L., Cephalandra indica Naud., and Tabernaemontana divaricata L., growing on the edges of Delhi Road, National Highway 2 (NH 2) near Dankuni, West Bengal. By analysing the activities of a few enzymes like superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase and phenolic peroxidase, it appears that among the five plants examined,Amaranthus and Cephalandra are equipped with a very good scavenging system to combat effects of air pollution. PMID:12018603

  16. Surface free radicals detection using molecular scavenging method on black spruce wood treated with cold, atmospheric-pressure plasmas

    NASA Astrophysics Data System (ADS)

    Hardy, Jean-Michel; Levasseur, Olivier; Vlad, Mirela; Stafford, Luc; Riedl, Bernard

    2015-12-01

    Formation of surface free radicals on wood surfaces during plasma treatment could be an important factor when it comes to wood coating adhesion enhancement. In order to explore this aspect, freshly sanded black spruce (Picea mariana) wood samples were exposed to either plane-to-plane atmospheric-pressure dielectric barrier discharge (AP-DBD) or the flowing afterglow of an AP-DBD and then dipped in a 2,2-diphenyl-1-picrylhydrazyl (DPPH) solution. Wood veneers (extracted to eliminate small molecules prior to each plasma treatment) showed an increase of their reaction rate toward DPPH after treatment in the AP-DBD operated in nominally pure He; a feature ascribed to the plasma-assisted formation of free radicals on the wood surface. Addition of trace amounts (0.1%) of O2 in the He plasma produced a decrease in DPPH reactivity, suggesting that oxygen-spruce interaction during plasma treatment quenches free radicals formation. Similar experiments performed using the flowing afterglow of AP-DBD operated in either N2 or N2/O2 showed that both treatments do not generate significant amount of surface free radicals. This partially results from oxygen-wood interactions due to the open-air configuration of the afterglow reactor.

  17. An efficient one pot syntheses of aryl-3,3'-bis(indolyl)methanes and studies on their spectral characteristics, DPPH radical scavenging-, antimicrobial-, cytotoxicity-, and antituberculosis activity

    NASA Astrophysics Data System (ADS)

    Suresh Kumar, G. S.; Kumaresan, S.; Antony Muthu Prabhu, A.; Bhuvanesh, N.; Seethalakshmi, P. G.

    2013-01-01

    An efficient one-pot syntheses of aryl-3,3'-bis(indolyl)methanes (BIMs) from indole/2-methylindole and formylphenoxyaliphatic acid(s) is described. Esterification of carboxylic acid and aromatic electrophilic substitution reactions are achieved simultaneous in the presence of potash alum as a catalyst. This catalyst could be recovered and reused without substantial loss in its catalytic activity and the methodology could be applied on a range of closely related substrates. The solvation characteristics in ground and excited states of the compounds by monitoring the absorbance and fluorescence band maxima have been studied. The fluorescence studies in protic and aprotic solvents were rationalized on the basis of solute-solvent interaction and substituents effect on these photophysical processes analyzed. The compounds prepared showed efficient antimicrobial effect against human pathogens, cytotoxicity against A431 cell line, and DPPH radical scavenging effect. Single crystal XRD studies have been carried out for a few compounds synthesized in this work.

  18. Free-radical scavenging properties of low molecular weight peptide(s) isolated from S1 cultivar of mulberry leaves and their impact on Bombyx mori (L.) (Bombycidae)

    PubMed Central

    2014-01-01

    The mulberry leaves have been considered as a sole food source for silkworm, Bombyx mori (L.). In present work an attempt was made to investigate the role of low molecular weight peptide(s) isolated from mulberry leaves on silkworm rearing. Also we have tried to find out the role of free-radical scavenging activities of isolated peptide(s) on silkworm growth. Larval growth rate was found effective under the influence of peptide(s). Consumption rate of larvae after peptide(s) treatment on mulberry leaves was significantly enhanced over control. High antioxidant activity was found in Low molecular weight peptide(s) which have an effect on silkworm. PMID:24612781

  19. A QSAR study of radical scavenging antioxidant activity of a series of flavonoids using DFT based quantum chemical descriptors--the importance of group frontier electron density.

    PubMed

    Sarkar, Ananda; Middya, Tapas Ranjan; Jana, Atish Dipnakar

    2012-06-01

    In a pursuit of electronic level understanding of the antioxidant activity of a series of flavonoids, quantitative structure-activity relationship (QSAR) studies have been carried out using density functional theory (DFT) based quantum chemical descriptors. The best QSAR model have been selected for which the computed square correlation coefficient r(2) = 0.937 and cross-validated squared correlation coefficient q(2) =0.916. The QSAR model indicates that hardness (η), group electrophilic frontier electron density (F(E)(A)) and group philicity (ω(B)(+)) of individual molecules are responsible for in vitro biological activity. To the best our knowledge, the group electrophilic frontier electron density (F(E)(A)) has been used for the first time to explain the radical scavenging activity (RSA) of flavonoids. The excellent correlation between the RSA and the above mentioned DFT based descriptors lead us to predict new antioxidants having very good antioxidant activity. PMID:22080306

  20. Molecular mechanisms for the reaction between (˙)OH radicals and proline: insights on the role as reactive oxygen species scavenger in plant stress.

    PubMed

    Signorelli, Santiago; Coitiño, E Laura; Borsani, Omar; Monza, Jorge

    2014-01-01

    The accumulation of proline (Pro) and overproduction of reactive oxygen species (ROS) by plants exposed to stress is well-documented. In vitro assays show that enzyme inactivation by hydroxyl radicals ((•)OH) can be avoided in the presence of Pro, suggesting this amino acid might act as a (•)OH scavenger. Although production of hydroxyproline (Hyp) has been hypothesized in connection with such antioxidant activity, no evidence on the detailed mechanism of scavenging has been reported. To elucidate whether and how Hyp might be produced, we used density functional theory calculations coupled to a polarizable continuum model to explore 27 reaction channels including H-abstraction by (•)OH and (•)OH/H2O addition. The structure and energetics of stable species and transition states for each reaction channel were characterized at the PCM-(U)M06/6-31G(d,p) level in aqueous solution. Evidence is found for a main pathway in which Pro scavenges (•)OH by successive H-abstractions (ΔG(‡,298) = 4.1 and 7.5 kcal mol(-1)) to yield 3,4-Δ-Pro. A companion pathway with low barriers yielding Δ(1)-pyrroline-5-carboxylate (P5C) is also supported, linking with 5-Hyp through hydration. However, this connection remains unlikely in stressed plants because P5C would be efficiently recycled to Pro (contributing to its accumulation) by P5C reductase, hypothesis coined here as the "Pro-Pro cycle". PMID:24328335

  1. Induction of the superoxide anion radical scavenging capacity of dried 'funori'Gloiopeltis furcata by Lactobacillus plantarum S-SU1 fermentation.

    PubMed

    Kuda, Takashi; Nemoto, Maki; Kawahara, Miho; Oshio, Satoshi; Takahashi, Hajime; Kimura, Bon

    2015-08-01

    To understand the beneficial properties of edible algae obtained from the north-eastern (Sanriku) Satoumi region of Japan, the antioxidant properties of hot aqueous extract solutions (AES) obtained from 18 dried algal products were determined. The samples included 4 Ceratophyllum demersum (matsumo), 5 Undaria pinnatifida (wakame), 5 Laminaria japonica (kombu), and 2 each of Gloiopeltis furcate (funori) and G. tenax (funori). Of these products, the total phenolic content and Fe-reducing power were highest in matsumo. On the other hand, the polysaccharide content, viscosity, and superoxide anion radical (O2˙(-))-scavenging capacity were highest in funori. Lactobacillus plantarum S-SU3, isolated from the intestine of Japanese surfperch, and Lb. plantarum S-SU1, isolated from salted squid, could ferment the AES of matsumo and funori, respectively. Although the Fe-reducing power of the matsumo solution was reduced due to fermentation, the O2˙(-)-scavenging capacity of the funori solution was increased by fermentation. Furthermore, the fermented funori suspension protected Saccharomyces cerevisiae, a live cell model, against H2O2 toxicity. These results suggest that the fermented funori is a promising functional food material that is capable of protecting against reactive oxygen species. PMID:26110834

  2. Vitamin E, γ-tocotrienol, Protects Against Buthionine Sulfoximine-Induced Cell Death by Scavenging Free Radicals in SH-SY5Y Neuroblastoma Cells.

    PubMed

    Tan, Jen-Kit; Then, Sue-Mian; Mazlan, Musalmah; Jamal, Rahman; Ngah, Wan Zurinah Wan

    2016-04-01

    The induction of reactive oxygen species (ROS) to selectively kill cancer cells is an important feature of radiotherapy and various chemotherapies. Depletion of glutathione can induce apoptosis in cancer cells or sensitize them to anticancer treatments intended to modulate ROS levels. In contrast, antioxidants protect cancer cells from oxidative stress-induced cell death by scavenging ROS. The role of exogenous antioxidants in cancer cells under oxidative insults remains controversial and unclear. This study aimed to identify protective pathways modulated by γ-tocotrienol (γT3), an isomer of vitamin E, in human neuroblastoma SH-SY5Y cells under oxidative stress. Using buthionine sulfoximine (BSO) as an inhibitor of glutathione synthesis, we found that BSO treatment reduced the viability of SH-SY5Y cells. BSO induced cell death by increasing apoptosis, decreased the level of reduced glutathione (GSH), and increased ROS levels in SH-SY5Y cells. Addition of γT3 increased the viability of BSO-treated cells, suppressed apoptosis, and decreased the ROS level induced by BSO, while the GSH level was unaffected. These results suggest that decreasing GSH levels by BSO increased ROS levels, leading to apoptosis in SH-SY5Y cells. γT3 attenuated the BSO-induced cell death by scavenging free radicals. PMID:27008382

  3. Putative free radical-scavenging activity of an extract of Cineraria maritima in preventing selenite-induced cataractogenesis in Wistar rat pups

    PubMed Central

    Anitha, Thirugnanasambandhar Sivasubramanian; Muralidharan, Arumugam Ramachandran; Annadurai, Thangaraj; Jesudasan, Christdas Arul Nelson; Thomas, Philip Aloysius

    2013-01-01

    Purpose To investigate the possible free radical-scavenging activity of an extract of Cineraria maritima on selenite-induced cataractous lenses in Wistar rat pups. Methods In the present study, Wistar rat pups were divided into three experimental groups. On P10, Group I (control) rat pups received an intraperitoneal injection of 0.89% saline. Rats in groups II (selenite-challenged, untreated) and III (selenite-challenged, C. maritima treated) received a subcutaneous injection of sodium selenite (19 μmol/kg bodyweight); Group III rat pups also received an intraperitoneal injection of the extract of C. maritima (350 mg/kg bodyweight) once daily P9–14. Both eyes of each pup were examined from P16 until P30. Cytochemical localization of nitroblue tetrazolium salts and generation of superoxide, hydroxyl, and nitric oxide levels were measured. The expression of the inducible nitric oxide synthase gene was evaluated with reverse transcription-PCR. Immunoblot analysis was also performed to confirm the differential expression of the inducible nitric oxide synthase protein. Results Subcutaneous injection of sodium selenite led to severe oxidative damage in the lenticular tissues, shown by increased formation of formazan crystals, elevated generation of superoxide, hydroxyl, and nitric oxide radicals, and elevated inducible nitric oxide synthase gene and protein expression that possibly contributed to the opacification of the lens and thus cataract formation. When rat pups were treated with intraperitoneal administration of the extract of C. maritima, the generation of free radicals as well as the messenger ribonucleic acid and protein expression of inducible nitric oxide synthase were maintained at near normal levels. Conclusions The data generated by this study suggest that an ethanolic extract of C. maritima possibly prevents cataractogenesis in a rat model by minimizing free radical generation. PMID:24357923

  4. Antimicrobial, free radical scavenging activities and catalytic oxidation of benzyl alcohol by nano-silver synthesized from the leaf extract of Aristolochia indica L.: a promenade towards sustainability

    NASA Astrophysics Data System (ADS)

    Shanmugam, C.; Sivasubramanian, G.; Parthasarathi, Bera; Baskaran, K.; Balachander, R.; Parameswaran, V. R.

    2015-07-01

    Silver nanoparticles (Ag-NPs) were synthesized from aqueous silver nitrate through a simple route using the leaf extract of Aristolochia indica L. (LAIL) which acted as a reducing as well as capping agent. X-ray diffraction confirmed that the synthesized silver particles have a face centred cubic structure. EDS predicted the presence of elemental silver. The SEM images showed the synthesis of spherically mono-dispersed particles, with nano dimensions accounted by the TEM images. Infra-red spectrum adopted to the different organic functionalities present at the surface of the particles. TGA indicated an overall 11 % weight loss up to 1000 °C, suggesting desorption of biomolecules from the surface. X-ray photoelectron spectroscopy (XPS) analysis revealed the presence of metallic silver nanoparticles. The prepared material was utilized as catalyst in the oxidation of benzyl alcohol with molecular oxygen as the oxidant in methanol, under ambient conditions of temperature and pressure. Also Ag-NPs showed good to moderate anti-microbial activity employing the Agar disc diffusion method against various strains using Ciprofloxacin and Fluconazole as standard. Free radical scavenging activity of the nanoparticles were observed by modified 1,1-diphynyl-2-picrylhydrazyl, DPPH and 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), ABTS in vitro assays. The work presented here demonstrates the adaptability of the synthesized Ag-NPs in participating as a disinfectant agent, free radical scavenger and an effective oxidation catalyst. The basic premise of attaining sustainability through the green synthesis of smart multifaceted materials has been consciously addressed.

  5. Changes in polyphenolic content and radical-scavenging activity of sweet potato (Ipomoea batatas L.) during storage at optimal and low temperatures.

    PubMed

    Ishiguro, Koji; Yahara, Shoji; Yoshimoto, Makoto

    2007-12-26

    Polyphenolic content and radical-scavenging activities (RSA) of four sweet potato (Ipomoea batatas L.) cultivars were characterized after storage at optimal (15 degrees C) or low temperature (5 degrees C) for 0, 13, 26, and 37 days. The polyphenolic content increased during storage in three cultivars but not in 'Murasakimasari'. The change in 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity (DPPH-RSA) correlated very well with polyphenolic content. The increases in polyphenolics and the RSA in 'Benimasari' were significantly greater during storage at 5 degrees C than at 15 degrees C. The main polyphenolic components in all cultivars were chlorogenic acid (ChA) and 3,5-di-O-caffeoylquinic acid (3,5-diCQA). ChA level increased more at 5 degrees C than at 15 degrees C, whereas that of 3,5-diCQA was greater at 15 degrees C. Caffeoylquinic acids and RSA in 'Murasakimasari', which contains a large amount of anthocyanin in flesh tissue, were extremely high at the beginning of storage and remained nearly constant or decreased over time. A non-caffeoylquinic acid component that increased during storage, especially in 'J-Red' at 15 degrees C, was purified by successive chromatographic steps. The isolate was identified as caffeoyl sucrose [CSu, 6-O-caffeoyl-(beta- d-fructofuranosyl-(2-->1))-alpha-D-glucopyranoside] by fast atom bombardment-mass spectroscopy (FAB-MS), infrared spectroscopy (IR), and nuclear magnetic resonance spectroscopy (NMR). These results suggest that storage under cultivar-dependent, controlled temperature is one approach for increasing desirable physiologic function associated with RSA of polyphenolic compounds in sweet potato roots. PMID:18038989

  6. Crystal structure, DFT and HF calculations and radical scavenging activities of (E)-4,6-dibromo-3-methoxy-2-[(3-methoxyphenylimino)methyl]phenol.

    PubMed

    Alaşalvar, Can; Soylu, Mustafa Serkan; Güder, Aytaç; Albayrak, Çiğdem; Apaydın, Gökhan; Dilek, Nefise

    2014-05-01

    In this study, (E)-4,6-dibromo-3-methoxy-2-[(3-methoxyphenylimino)methyl]phenol has been synthesized and characterized by using X-ray technique and FT-IR experimentally and using B3LYP/6-31G(d,p) and HF/6-31G(d,p) methods theoretically. The intermolecular and intramolecular interactions of the title compound have been determined according to X-ray results. The molecular geometry, vibrational frequencies of the title compound in the ground state have been calculated using the density functional B3LYP and HF method with the 6-31G(d,p) basis set and calculated bond parameters and vibrational frequencies values show good agreement with experimental values. Theoretical and experimental results show that tautomeric form of the structure is phenol-imine form. Besides HOMO-LUMO energy gap, molecular electrostatic potential map were performed at B3LYP/6-31G(d,p) level. It is worthy note of that, the free radical scavenging activities of the title compound were assessed using DPPH˙, DMPD˙(+), and ABTS˙(+) assays. The obtained results show that the title compound has effective DPPH˙ (SC50 2.61±0.09 μg/mL), DMPD˙(+) (SC50 2.82±0.14 μg/mL), and ABTS˙(+) (SC50 4.91±0.18 μg/mL) radical scavenging activities when compared with standard antioxidants (BHA, rutin, and trolox). PMID:24566110

  7. Antimicrobial, free radical scavenging activities and catalytic oxidation of benzyl alcohol by nano-silver synthesized from the leaf extract of Aristolochia indica L.: a promenade towards sustainability

    NASA Astrophysics Data System (ADS)

    Shanmugam, C.; Sivasubramanian, G.; Parthasarathi, Bera; Baskaran, K.; Balachander, R.; Parameswaran, V. R.

    2016-06-01

    Silver nanoparticles (Ag-NPs) were synthesized from aqueous silver nitrate through a simple route using the leaf extract of Aristolochia indica L. (LAIL) which acted as a reducing as well as capping agent. X-ray diffraction confirmed that the synthesized silver particles have a face centred cubic structure. EDS predicted the presence of elemental silver. The SEM images showed the synthesis of spherically mono-dispersed particles, with nano dimensions accounted by the TEM images. Infra-red spectrum adopted to the different organic functionalities present at the surface of the particles. TGA indicated an overall 11 % weight loss up to 1000 °C, suggesting desorption of biomolecules from the surface. X-ray photoelectron spectroscopy (XPS) analysis revealed the presence of metallic silver nanoparticles. The prepared material was utilized as catalyst in the oxidation of benzyl alcohol with molecular oxygen as the oxidant in methanol, under ambient conditions of temperature and pressure. Also Ag-NPs showed good to moderate anti-microbial activity employing the Agar disc diffusion method against various strains using Ciprofloxacin and Fluconazole as standard. Free radical scavenging activity of the nanoparticles were observed by modified 1,1-diphynyl-2-picrylhydrazyl, DPPH and 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), ABTS in vitro assays. The work presented here demonstrates the adaptability of the synthesized Ag-NPs in participating as a disinfectant agent, free radical scavenger and an effective oxidation catalyst. The basic premise of attaining sustainability through the green synthesis of smart multifaceted materials has been consciously addressed.

  8. The free radical scavenger Trolox dampens neuronal hyperexcitability, reinstates synaptic plasticity, and improves hypoxia tolerance in a mouse model of Rett syndrome

    PubMed Central

    Janc, Oliwia A.; Müller, Michael

    2014-01-01

    Rett syndrome (RS) causes severe cognitive impairment, loss of speech, epilepsy, and breathing disturbances with intermittent hypoxia. Also mitochondria are affected; a subunit of respiratory complex III is dysregulated, the inner mitochondrial membrane is leaking protons, and brain ATP levels seem reduced. Our recent assessment of mitochondrial function in MeCP2 (methyl-CpG-binding protein 2)-deficient mouse (Mecp2-/y) hippocampus confirmed early metabolic alterations, an increased oxidative burden, and a more vulnerable cellular redox balance. As these changes may contribute to the manifestation of symptoms and disease progression, we now evaluated whether free radical scavengers are capable of improving neuronal and mitochondrial function in RS. Acute hippocampal slices of adult mice were incubated with the vitamin E derivative Trolox for 3–5 h. In Mecp2-/y slices this treatment dampened neuronal hyperexcitability, improved synaptic short-term plasticity, and fully restored synaptic long-term potentiation (LTP). Furthermore, Trolox specifically attenuated the increased hypoxia susceptibility of Mecp2-/y slices. Also, the anticonvulsive effects of Trolox were assessed, but the severity of 4-aminopyridine provoked seizure-like discharges was not significantly affected. Adverse side effects of Trolox on mitochondria can be excluded, but clear indications for an improvement of mitochondrial function were not found. Since several ion-channels and neurotransmitter receptors are redox modulated, the mitochondrial alterations and the associated oxidative burden may contribute to the neuronal dysfunction in RS. We confirmed in Mecp2-/y hippocampus that Trolox dampens neuronal hyperexcitability, reinstates synaptic plasticity, and improves the hypoxia tolerance. Therefore, radical scavengers are promising compounds for the treatment of neuronal dysfunction in RS and deserve further detailed evaluation. PMID:24605086

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

    PubMed

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

    2016-08-01

    The present study investigates the interaction of citrate stabilized gold nanoparticles (12±1.5nm) (GNPs) with free radicals; 1,1-diphenyl-2-picrylhydrazyl (DPPH) stable and electrochemically generated superoxide, O2(-). Different experiments were designed to understand the interaction between GNPs and DPPH by employing cyclic voltammetry, UV-vis spectroscopy and computational chemistry using 6-311G basis set. The increase in heterogeneous rate constant, ksh, of DPPH upon addition of GNPs pointed towards possible complex formation, DPPH-GNPs which were further explained by a model assuming surface adsorption of DPPH on GNPs. Further, the model was validated by studying interaction of GNPs with a biologically important free radical, O2(-). Exciting result in terms of disappearance of anodic peak after GNPs addition confirmed that gold nanoparticles interacted with stable as well as unstable free radicals. Also, the stoichiometry of the most stable complex GNP-DPPH was determined from UV-vis spectroscopy by applying Job's method. The GNP-DPPH complex was found to be active with 46.0% reduction of the IC50 value of standard antioxidant, ascorbic acid (AA), indicating its role in enhancing antioxidant activity. Hence, this study presents a simple and potential approach to enhance the efficiency of natural antioxidants without modifying their structure, or involving the complex functionalization of GNPs with antioxidants. PMID:27288656

  10. In vitro antioxidant activities, free radical scavenging capacity, and tyrosinase inhibitory of flavonoid compounds and ferulic acid from Spiranthes sinensis (Pers.) Ames.

    PubMed

    Liang, Chung Pin; Chang, Chia Hao; Liang, Chien Cheng; Hung, Kuei Yu; Hsieh, Chang Wei

    2014-01-01

    In this study, ultrasound-assisted extraction (UAE) and other methods of extracting flavonoid compounds and ferulic acid (FA) from S. sinensis were investigated. Five different extraction methods, including water extraction (W), water extraction using UAE (W+U), 75% ethanol extraction (E), 75% ethanol extraction using UAE (E+U), and supercritical CO2 extraction (SFE) were applied in the extraction of bioactive compounds (flavonoids and ferulic acid) in order to compare their efficiency. The highest yield of flavonoids (4.28 mg/g) and ferulic acid (4.13 mg/g) content was detected in the E+U extract. Furthermore, S. sinensis extracts obtained by E+U show high antioxidant activity, and IC50 values of 0.47 mg/mL for DPPH radicals and 0.205 mg/mL for metal chelating activity. The total antioxidant assay shows superoxide radical scavenging capacity and in vitro mushroom tyrosinase inhibition in a dose-dependent manner, suggesting that E+U can be used for extraction of bioactive compounds from S. sinensis. PMID:24739930

  11. Assessment of phenolic content, free-radical-scavenging capacity genotoxic and anti-genotoxic effect of aqueous extract prepared from Moricandia arvensis leaves.

    PubMed

    Skandrani, I; Limem, I; Neffati, A; Boubaker, J; Ben Sghaier, M; Bhouri, W; Bouhlel, I; Kilani, S; Ghedira, K; Chekir-Ghedira, L

    2010-02-01

    The present study was undertaken to provide a set of data on the safety of an aqueous extract (AQE) from Moricandia arvensis. For this reason, Escherichia coli tested strains PQ35 and PQ37 were used to detect induction of DNA lesions by AQE. The SOS Chromotest showed that AQE induced a marginally genotoxic effect, as expressed by the induction factor (IF) value only with E. coli PQ37 tested strain (IF=1.77 at a dose of 250 microg/assay). The measurement of the anti-genotoxic activity of the AQE was also studied by inhibition of beta-galactosidase induction. A significant anti-genotoxic effect was observed with different tested doses of AQE, which suggests that M. arvensis extract has the potential to protect DNA from the action of nitrofurantoïn (NF) and free radicals generated by hydrogen peroxide (H2O2). In addition to anti-genotoxic activity, AQE showed a free-radical-scavenging capacity towards ABTS+* and DPPH*. Total phenolic content was also evaluated following Folin-Ciocalteu method and results indicated high correlation between total phenol content and anti-genotoxic and antioxidant activities for AQE, but the highest correlation was showed with its capacity to stabilize ABTS+* (R2=0.9944). PMID:19951736

  12. Anti-inflammatory, free radical scavenging and alpha-glucosidase inhibitory activities of Hamelia patens and its chemical constituents.

    PubMed

    Jiménez-Suárez, Verónica; Nieto-Camacho, Antonio; Jiménez-Estrada, Manuel; Alvarado Sánchez, Brenda

    2016-09-01

    Context Hamelia patens Jacq. (Rubiaceae) is traditionally used to treat wounds, inflammation and diabetes. However, there is still a lack of scientific evidence to support these applications. Objective The objective of this study is to evaluate the anti-inflammatory, antioxidant and antidiabetic activities of Hamelia patens, and identify its bioactive compounds. Materials and methods Four extracts were obtained by maceration and liquid-liquid extraction: HEX, DCM-EtOAc, MeOH-EtOAc and MeOH-Aq. The anti-inflammatory effect was evaluated orally on rat paw carrageenan-induced oedema over 6 h (50, 200 and 500 mg/kg), and topically in mouse ear oedema induced by 12-tetradecanoylphorbol-13-acetate (TPA) after 4 h (0.5 and 1 mg/ear). We also evaluated myeloperoxidase levels in ear tissue, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability, and in vitro α-glucosidase inhibition. The chemical compounds were separated by column chromatography and identified by spectroscopic analysis. Results We found that the oral administration of the HEX extract at 500 and 200 mg/kg significantly decreased the carrageenan-induced inflammation after 1 and 3 h, respectively. The MeOH-EtOAc extract significantly inhibited myeloperoxidase activity (83.5%), followed by the DCM-EtOAc extract (76%), β-sitosterol/stigmasterol (72.7%) and the HEX extract (55%), which significantly decreased oedema induced by TPA at both doses, giving a similar effect to indomethacin. We also found that the MeOH-EtOAc, MeOH-Aq and DCM-EtOAc extracts showed good DPPH scavenging activity (IC50 values of 18.6, 93.9 and 158.2 μg/mL, respectively). The HEX extract showed the lowest α-glucosidase inhibition (an IC50 value of 26.07 μg/mL), followed by the MeOH-EtOAc extract (an IC50 value of 30.18 μg/mL), β-sitosterol/stigmasterol (IC50 34.6 μg/mL) and compound A ((6E,10E,14E,18E)-2,6,10,14,18,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene, an IC50 value of 114.6 μg/mL), which were

  13. Inhibition of the Conversion of 1-Aminocyclopropane-1-carboxylic Acid to Ethylene by Structural Analogs, Inhibitors of Electron Transfer, Uncouplers of Oxidative Phosphorylation, and Free Radical Scavengers 1

    PubMed Central

    Apelbaum, Akiva; Wang, Shiow Y.; Burgoon, Alan C.; Baker, James E.; Lieberman, Morris

    1981-01-01

    Cyclopropane carboxylic acid (CCA) at 1 to 5 millimolar, unlike related cyclopropane ring analogs of 1-aminocyclopropane-1-carboxylic acid (ACC) which were virtually ineffective, inhibited C2H4 production, and this inhibition was nullified by ACC. Inhibition by CCA is not competitive with ACC since there is a decline, rather than an increase, in native endogenous ACC in the presence of CCA. Similarly, short-chain organic acids from acetic to butyric acid and α-aminoisobutyric acid inhibited C2H4 production at 1 to 5 millimolar and lowered endogenous ACC levels. These inhibitions, like that of CCA, were overcome with ACC. Inhibitors of electron transfer and oxidative phosphorylation effectively inhibited ACC conversion to C2H4 in pea and apple tissues. The most potent inhibitors were 2,4-dinitrophenol (DNP) and carbonyl cyanide m-chlorophenylhydrazone (CCCP) which virtually eliminated ACC-stimulated C2H4 production in both tissues. Still other inhibitors of the conversion of ACC to C2H4 were putative free radical scavengers which reduced chemiluminescence in the free radical-activated luminol reaction. These inhibitor studies suggest the involvement of a free radical in the reaction sequence which converts ACC to C2H4. Additionally, the potent inhibition of this reaction by uncouplers of oxidative phosphorylation (DNP and CCCP) suggest the involvement of ATP or the necessity for an intact membrane for C2H4 production from ACC. In the latter case, CCCP may be acting as a proton ionophore to destroy the membrane integrity necessary for C2H4 production. PMID:16661637

  14. Metal chelation, radical scavenging and inhibition of Aβ₄₂ fibrillation by food constituents in relation to Alzheimer's disease.

    PubMed

    Chan, Stephen; Kantham, Srinivas; Rao, Venkatesan M; Palanivelu, Manoj Kumar; Pham, Hoang L; Shaw, P Nicholas; McGeary, Ross P; Ross, Benjamin P

    2016-05-15

    Various food constituents have been proposed as disease-modifying agents for Alzheimer's disease (AD), due to epidemiological evidence of their beneficial effects, and for their ability to ameliorate factors linked to AD pathogenesis, namely by: chelating iron, copper and zinc; scavenging reactive oxygen species; and suppressing the fibrillation of amyloid-beta peptide (Aβ). In this study, nine different food constituents (l-ascorbic acid, caffeic acid, caffeine, curcumin, (-)-epigallocatechin gallate (EGCG), gallic acid, propyl gallate, resveratrol, and α-tocopherol) were investigated for their effects on the above factors, using metal chelation assays, antioxidant assays, and assays of Aβ42 fibrillation. An assay method was developed using 5-Br-PAPS to examine the complexation of Zn(II) and Cu(II). EGCG, gallic acid, and curcumin were identified as a multifunctional compounds, however their poor brain uptake might limit their therapeutic effects. The antioxidants l-ascorbic acid and α-tocopherol, with better brain uptake, deserve further investigation for specifically addressing oxidative stress within the AD brain. PMID:26775960

  15. Is Nitrate radical a major oxidant of elemental mercury in the atmosphere?

    NASA Astrophysics Data System (ADS)

    Luria, M.; Obrist, D.; Peleg, M.; Matveev, V.; Tas, E.

    2012-12-01

    Nitrate radicals (NO3) play a major role in the nighttime atmospheric oxidation of VOC. The radicals are produced throughout the reaction between O3 and NO2 and are removed via a sequence of homogeneous and heterogeneous reactions. Nitrate radicals reach significant levels only at night and mostly under conditions of low humidity (Asaf et al, 2009, 2010 and references therein). Because of its very high photolysis rate, daytime levels are extremely low, and thus are insignificant in atmospheric oxidation processes. The reaction of Hg with NO3 has not been sufficiently investigated; a value of 4x10-15 cm3 molec-1 s-1 (Sommar et al 1997) is most commonly used. Its importance for the atmospheric mercury chemistry was discussed by Mao el al., (2008) who examined the potential oxidation of mercury by the most common atmospheric oxidants applying the best available rate coefficients. According to their report, the uncertainty in the oxidation capacity of O3 is very large (a factor of 20). If the lower limit is applied, as suggested by Calvert and Lindberg (2005), oxidation by O3 is nearly negligible and, NO3 radicals, at typical nighttime levels, are responsible for the bulk of the Hg oxidation. Obviously this is true in the absence of reactive halogen compounds (RHC, Peleg et al., 2008). The most common method of measuring nitrate radicals is the differential optical absorption system (DOAS) technique. In a recent study performed at an urban semi arid site (Jerusalem, Israel; Asaf et al., 2009, 2010) it was found that nitrate levels could reach levels of up to 800 ppt, significantly higher than ever reported in the past. They further demonstrated that under the conditions prevailed; nitrate radicals are at least as important as the hydroxyl radicals in the overall oxidation capacity of VOC in the atmosphere. Side by side measurements of Nitrate radicals using the DOAS technique and speciated mercury compounds (Total, Particulate and Reactive gaseous) were performed

  16. Evidence for the Therapeutic Efficacy of Either Mild Hypothermia or Oxygen Radical Scavengers after Repetitive Mild Traumatic Brain Injury

    PubMed Central

    Miyauchi, Takashi; Wei, Enoch P.

    2014-01-01

    Abstract Repetitive brain injury, particularly that occurring with sporting-related injuries, has recently garnered increased attention in both the clinical and public settings. In the laboratory, we have demonstrated the adverse axonal and vascular consequences of repetitive brain injury and have demonstrated that moderate hypothermia and/or FK506 exerted protective effects after repetitive mild traumatic brain injury (mTBI) when administered within a specific time frame, suggesting a range of therapeutic modalities to prevent a dramatic exacerbation. In this communication, we revisit the utility of targeted therapeutic intervention to seek the minimal level of hypothermia needed to achieve protection while probing the role of oxygen radicals and their therapeutic targeting. Male Sprague-Dawley rats were subjected to repetitive mTBI by impact acceleration injury. Mild hypothermia (35°C, group 2), superoxide dismutase (group 3), and Tempol (group 4) were employed as therapeutic interventions administered 1 h after the repetitive mTBI. To assess vascular function, cerebral vascular reactivity to acetylcholine was evaluated 3 and 4 h after the repetitive mTBI, whereas to detect the burden of axonal damage, amyloid precursor protein (APP) density in the medullospinal junction was measured. Whereas complete impairment of vascular reactivity was observed in group 1 (without intervention), significant preservation of vascular reactivity was found in the other groups. Similarly, whereas remarkable increase in the APP-positive axon was observed in group 1, there were no significant increases in the other groups. Collectively, these findings indicate that even mild hypothermia or the blunting free radical damage, even when performed in a delayed period, is protective in repetitive mTBI. PMID:24341607

  17. Determination of Free Radical Scavenging, Antioxidative DNA Damage Activities and Phytochemical Components of Active Fractions from Lansium domesticum Corr. Fruit

    PubMed Central

    Klungsupya, Prapaipat; Suthepakul, Nava; Muangman, Thanchanok; Rerk-Am, Ubon; Thongdon-A, Jeerayu

    2015-01-01

    Lansium domesticum Corr. or “long-kong” is one of the most popular fruits in Thailand. Its peel (skin, SK) and seeds (SD) become waste unless recycled or applied for use. This study was undertaken to determine the bioactivity and phytochemical components of L. domesticum (LD) skin and seed extracts. Following various extraction and fractionation procedures, 12 fractions were obtained. All fractions were tested for antioxidant capacity against O2−• and OH•. It was found that the peel of L. domesticum fruits exhibited higher O2−• and OH• scavenging activity than seeds. High potential antioxidant activity was found in two fractions of 50% ethanol extract of peel followed by ethyl acetate (EA) fractionation (LDSK50-EA) and its aqueous phase (LDSK50-H2O). Therefore, these two active fractions were selected for further studies on their antioxidative activity against DNA damage by hydrogen peroxide (H2O2) in human TK6 cells using comet assay. The comet results revealed DNA-protective activity of both LDSK50-EA and LDSK50-H2O fractions when TK6 human lymphoblast cells were pre-treated at 25, 50, 100, and 200 μg/mL for 24 h prior to H2O2 exposure. The phytochemical analysis illustrated the presence of phenolic substances, mainly scopoletin, rutin, and chlorogenic acid, in these two active fractions. This study generates new information on the biological activity of L. domesticum. It will promote and strengthen the utilization of L. domesticum by-products. PMID:26287238

  18. Effect of pumpkin-seed oil on the level of free radical scavengers induced during adjuvant-arthritis in rats.

    PubMed

    Fahim, A T; Abd-el Fattah, A A; Agha, A M; Gad, M Z

    1995-01-01

    Pumpkin-seed oil (PSO), a natural supplement rich with antioxidant ingredients, was given to rats in which arthritis was induced using Freund's complete adjuvant. Its effect was compared with that of indomethacin, as a classical anti-inflammatory agent. Two experimental patterns were studied, an acute phase that was applied only with PSO and a chronic phase applied for both PSO and indomethacin. Compared to normal untreated rats, it was shown that the induction of arthritis caused a decrease in serum sulphhydryl groups, with an increase in serum ceruloplasmin in both phases. Blood glutathione was first elevated in the acute phase, then its level was reduced in the chronic phase. Serum N-acetyl-beta-D-glucosaminidase activity was elevated only at the acute phase, while plasma total proteins and albumin were reduced at the chronic phase. Liver glucose-6-phosphate dehydrogenase activity was markedly increased, while no changes were observed in the levels of liver lipid peroxides and glutathione. These changes in the studied parameters were attributed to the superoxides and free radicals during arthritic inflammation. Administration of PSO succeeded in modulating most of the altered parameters affected during arthritis, especially at the chronic phase. Also, a remarkable inhibition of paw oedema was observed. A similar pattern was obtained upon treatment with indomethacin except that indomethacin markedly elevated liver lipid peroxides levels. Concurrent administration of PSO with indomethacin caused no changes in the parameters studied compared to that induced by treatment with indomethacin alone. PMID:7784309

  19. Scavenging of free radicals in gas-phase mainstream cigarette smoke by immobilized catalase at filter level.

    PubMed

    Lu, Xin; Hua, Zhaozhe; Du, Guocheng; Ma, Xiaolong; Cao, Jianhua; Yang, Zhanping; Chen, Jian

    2008-03-01

    Catalase is well known as capable of inducing the decomposition of H(2)O(2). In this study, a kind of immobilized catalase (entrapped in cross-linked chitosan beads) was dispersed in conventional acetate filter as an antioxidant additive. Quantitative estimation of the free radicals in mainstream cigarette smoke (MCS) was performed to address the effect of this modified filter. It was found that the levels of PBN adduct and NO(*)/NO(2)(*) associated with the gas-phase mainstream cigarette smoke (GPCS) were efficiently decreased by approximately 40% through catalase filtering. Besides, the modified filter was found to lower the MCS-induced adverse biological effects including lipid peroxidation and mutagenicity. This was proved to be substantially attributed to the catalase-dependent breakdown of NO(*), which was stimulated by some of peroxides (most probably being H(2)O(2)), the dismutation products of tar particulate matters (TPM). These results highlighted a promising approach to reduce the smoking-associated health risks to passive smokers. Moreover, the mechanisms of catalase filtering may be helpful for the development of appropriate immobilized enzyme systems to be applied for reducing health risks associated with gaseous pollutants. PMID:18344119

  20. Evaluation of chemical constituents and free-radical scavenging activity of Swarnabhasma (gold ash), an ayurvedic drug.

    PubMed

    Mitra, A; Chakraborty, S; Auddy, B; Tripathi, P; Sen, S; Saha, A V; Mukherjee, B

    2002-05-01

    From ancient times, Swarnabhasma (gold ash) has been used in several clinical manifestations including loss of memory, defective eyesight, infertility, overall body weakness and incidence of early aging. Swarnabhasma has been used by Ayurvedic physicians to treat different diseases like bronchial asthma, rheumatoid arthritis, diabetes mellitus, nervous disorders, etc. In the present investigation, Swarnabhasma was prepared after proper purification and calcination as per Ayurvedic pharmacy which consisted of Realger (As(2)S(2)), Lead oxide (Pb(3)O(4)), Pure gold (Au) and Latex of Calotropis gigantea. Qualitative analyses indicated that Swarnabhasma contained not only gold but also several microelements (Fe, Al, Cu, Zn, Co, Mg, Ca, As, Pb, etc.). Infrared spectroscopy showed that the material was free from any organic compound. The metal content in the bhasma was determined by atomic absorption spectrometry. Acute oral administration of Swarnabhasma showed no mortality in mice (up to 1 ml /20 g b.w. of Swarnabhasma suspension containing 1mg of drug). Chronic administration of Swarnabhasma also showed no toxicity as judged by SGPT, SGOT, serum creatinine and serum urea level and histological studies. In an experimental animal model, chronic Swarnabhasma-treated animals showed significantly increased superoxide dismutase and catalase activity, two enzymes that reduce free radical concentrations in the body. PMID:12007704

  1. Ameliorative effect of alkaloid extract of Cyclea peltata (Poir.) Hook. f. & Thoms. roots (ACP) on APAP/CCl4 induced liver toxicity in Wistar rats and in vitro free radical scavenging property

    PubMed Central

    Shine, Varghese Jancy; Latha, Panikamparambil Gopalakrishnan; Suja, Somasekharan Nair Rajam; Anuja, Gangadharan Indira; Raj, Gopan; Rajasekharan, Sreedharan Nair

    2014-01-01

    Objective To evaluate the hepatoprotective and antioxidant properties of alkaloid extract of Cyclea peltata (C. peltata) against paracetamol/carbon tetra chloride induced liver damage in Wistar rats. Methods In vivo paracetamol/carbon tetrachloride induced liver damage in Wistar rats, in vitro free radical scavenging studies, HPTLC estimation of tetrandrine and direct analysis in real time- mass spectrometry of alkaloid extract of C. peltata were used for the validation. Results The results showed that pretreatment with alkaloid extract of C. peltata caused significant reduction of serum glutamate pyruvate transaminase, serum glutamate oxaloacetate transaminase, serum alkaline phosphatase, serum cholesterol, liver malondialdehyde levels. The reduced glutathione, catalase, superoxide dismutase levels in liver were increased with alkaloid extract of C. peltata treatment. These results were almost comparable to silymarin and normal control. Histopathological studies also substantiated the biochemical findings. The in vitro hydroxyl, superoxide and DPPH scavenging study of alkaloid extract of C. peltata showed significant free radical scavenging property. Conclusions The hepatoprotective property of alkaloid extract of C. peltata against paracetamol/carbon tetrachloride may be due the synergistic action of alkaloids especially tetrandrine, fangchinoline through free radical scavenging and thus preventing oxidative stress. PMID:25182286

  2. Well-defined azlactone-functionalized (co)polymers on a solid support: synthesis via supported living radical polymerization and application as nucleophile scavengers.

    PubMed

    Fournier, David; Pascual, Sagrario; Montembault, Véronique; Haddleton, David M; Fontaine, Laurent

    2006-01-01

    Wang resin has been converted to a supported initiator for transition metal-mediated living radical polymerization often called atom-transfer radical polymerization (ATRP) of 2-vinyl-4,4-dimethyl-5-oxazolone (VDM) and styrene (S). Several "Rasta" resins with well-defined macromolecular architectures, including homopolymers PVDM, PS, statistical P(S-stat-VDM), block P(S-b-VDM), and P[S-b-(S-stat-VDM)] copolymers, have been elaborated. For the homopolymerization of VDM and S, a sacrificial initiator, benzyl 2-bromoisobutyrate (BBI), has been introduced to monitor the evolution of molar masses and polydispersity indexes (PDIs) of PS and PVDM onto the Wang resin support without cleavage. After 6 h, 86.7% conversion of VDM is reached, with the isolated PVDM chains having a molar mass of 18 000 g mol(-1) and a PDI value of 1.22. Block copolymers have been synthesized in two steps, involving the synthesis of the PS block isolated at low conversions (<15%) to maintain the bromine end-chain functionality and the subsequent synthesis of the second PVDM or P(S-stat-VDM) block. Polydispersity indexes of the cleaved (co)polymers were low (PDI = 1.11-1.44), and high azlactone loadings have been reached (loading = 6.0 mmol g(-1)). Such azlactone-functionalized Wang resins have shown high efficiency during the scavenging process of benzylamine as monitored by HPLC. Moreover, grafted statistical copolymers have shown the best behavior for removing benzylamine because of an improvement of the accessibility of azlactone rings by the dilution with styrene units. PMID:16827564

  3. Synthesis, crystal structure investigation, DFT studies and DPPH radical scavenging activity of 1-(furan-2-ylmethyl)-2,4,5-triphenyl-1H-imidazole derivatives

    NASA Astrophysics Data System (ADS)

    Rajaraman, D.; Sundararajan, G.; Rajkumar, R.; Bharanidharan, S.; Krishnasamy, K.

    2016-03-01

    A new series of 1-(furan-2ylmethyl)-2,4,5-triphenyl-1H-imidazole derivatives are conveniently synthesized and characterized by IR, 1H NMR and 13C NMR spectral techniques. The compound 5a also characterized by HSQC correlation spectra. All the newly synthesized compounds were evaluated for their antioxidant activities with DPPH radical scavenging activity. The structure of 5e was also confirmed by single crystal XRD analysis and optimized bond parameters are calculated by density functional theory (DFT) method at B3LYP/6-31G (d, p) level of theory. The optimized geometrical parameters obtained by DFT calculation are in good agreement with single crystal XRD data. The experimentally observed FT-IR and FT-Raman bands were assigned to different normal modes of the molecule. The stability and charge delocalization of the molecule were also studied by natural bond orbital (NBO) analysis. The HOMO-LUMO energies describe the charge transfer takes place within the molecule. Molecular electrostatic potential has been analyzed. The reported 5e molecule used as a potential NLO material since it has high μβ0 value.

  4. Radical Scavenging Activity-Based and AP-1-Targeted Anti-Inflammatory Effects of Lutein in Macrophage-Like and Skin Keratinocytic Cells

    PubMed Central

    Oh, Jueun; Kim, Ji Hye; Park, Jae Gwang; Yi, Young-Su; Park, Kye Won; Rho, Ho Sik; Lee, Min-Seuk; Yoo, Jae Won; Kang, Seung-Hyun; Hong, Yong Deog; Shin, Song Seok; Cho, Jae Youl

    2013-01-01

    Lutein is a naturally occurring carotenoid with antioxidative, antitumorigenic, antiangiogenic, photoprotective, hepatoprotective, and neuroprotective properties. Although the anti-inflammatory effects of lutein have previously been described, the mechanism of its anti-inflammatory action has not been fully elucidated. Therefore, in the present study, we aimed to investigate the regulatory activity of lutein in the inflammatory responses of skin-derived keratinocytes or macrophages and to elucidate the mechanism of its inhibitory action. Lutein significantly reduced several skin inflammatory responses, including increased expression of interleukin-(IL-) 6 from LPS-treated macrophages, upregulation of cyclooxygenase-(COX-) 2 from interferon-γ/tumor necrosis-factor-(TNF-) α-treated HaCaT cells, and the enhancement of matrix-metallopeptidase-(MMP-) 9 level in UV-irradiated keratinocytes. By evaluating the intracellular signaling pathway and the nuclear transcription factor levels, we determined that lutein inhibited the activation of redox-sensitive AP-1 pathway by suppressing the activation of p38 and c-Jun-N-terminal kinase (JNK). Evaluation of the radical and ROS scavenging activities further revealed that lutein was able to act as a strong anti-oxidant. Taken together, our findings strongly suggest that lutein-mediated AP-1 suppression and anti-inflammatory activity are the result of its strong antioxidative and p38/JNK inhibitory activities. These findings can be applied for the preparation of anti-inflammatory and cosmetic remedies for inflammatory diseases of the skin. PMID:23533312

  5. Non-enzymatic browning reaction of glucosamine at mild conditions: Relationship between colour formation, radical scavenging activity and α-dicarbonyl compounds production.

    PubMed

    Hong, Pui Khoon; Betti, Mirko

    2016-12-01

    Glucosamine (GlcN, 5% w/v) was incubated in either phosphate buffer or ammonium hydroxide solutions at 40 and 60°C for up to 48h in order to yield caramel solutions. Non-enzymatic browning was monitored via changes in absorption at 280, 320 and 420nm and the physico-chemical properties as well as the generation of short chain α-dicarbonyl compounds were evaluated. Accumulation of GlcN autocondensation products (280nm) proceeded in parallel with the development of pre-melanoidins (320nm) and melanoidins (420nm). The reactive α-dicarbonyls were detected at temperature as low as 40°C within 3h with a maximum level of diacetyl recorded at 6h. The caramel solutions showed a high efficacy in scavenging DPPH and ABTS radicals in accordance with the increasing browning intensity. The results suggest that GlcN browning can be modulated according to the specific desired properties to produce a multi-functional food ingredient that has health-promoting effects. PMID:27374528

  6. Changes in the radical-scavenging activity of bitter gourd (Momordica charantia L.) during freezing and frozen storage with or without blanching.

    PubMed

    Myojin, C; Enami, N; Nagata, A; Yamaguchi, T; Takamura, H; Matoba, T

    2008-09-01

    The effects of blanching, freezing, and frozen storage on the retention of radical-scavenging activity (RSA), total phenolics, and ascorbic acid in bitter gourd were investigated. Blanching of sliced bitter gourd resulted in considerable losses of RSA and total phenolics, and most extensively, of ascorbic acid. In the subsequent frozen storage at -18 degrees C, RSA and total phenolic content of unblanched and blanched bitter gourd underwent little change for 90 d then gradually declined, but at -40 degrees C, they practically remained unchanged throughout the entire storage period. On the contrary, ascorbic acid content of both unblanched and blanched bitter gourd decreased abruptly at the early stage in frozen storage. The results show that blanching of bitter gourd improves the retention of RSA and total phenolics during subsequent frozen storage but markedly aggravated loss of ascorbic acid. Finally, it is to be noted that RSA, total phenolics, and ascorbic acid originally contained in the raw bitter gourd were overall best retained by quick freezing followed by frozen storage at -40 degrees C without preceding blanching. PMID:18803700

  7. Spectroscopy investigation on chemo-catalytic, free radical scavenging and bactericidal properties of biogenic silver nanoparticles synthesized using Salicornia brachiata aqueous extract

    NASA Astrophysics Data System (ADS)

    Seralathan, Janani; Stevenson, Priscilla; Subramaniam, Shankar; Raghavan, Rachana; Pemaiah, Brindha; Sivasubramanian, Aravind; Veerappan, Anbazhagan

    2014-01-01

    Nanosized silver have been widely used in many applications, such as catalysis, photonics, sensors, medicine etc. Thus, there is an increasing need to develop high-yield, low cost, non-toxic and eco-friendly procedures for the synthesis of nanoparticles. Herein, we report an efficient, green synthesis of silver nanoparticles utilizing the aqueous extract of Salicornia brachiata, a tropical plant of the Chenopodiaceae family. Silver nanoparticles have been characterized by ultraviolet-visible spectroscopy, scanning electron microscopy and transmission electron microscopy. The morphology of the particles formed consists of highly diversified shapes like spherical, rod-like, prism, triangular, pentagonal and hexagonal pattern. However, addition of sodium hydroxide to the extract produces mostly spherical particles. The stable nanoparticles obtained using this green method show remarkable catalytic activity in the reduction of 4-nitro phenol to 4-amino phenol. The reduction catalyzed by silver nanoparticles followed the first-order kinetics, with a rate constant of, 0.6 × 10-2 s-1. The bactericidal activity of the synthesized silver nanoparticles against the pathogenic bacteria, Staphylococcus aureus, Staphylococcus aureus E, Bacillus subtilis and Escherichia coli, was also explored using REMA. The obtained results showed that the minimum inhibitory concentration required to induce bactericidal effect is lower than the control antibiotic, ciprofloxacin. In addition to these, the biogenic synthesized nanoparticles also exhibited excellent free radical scavenging activity.

  8. Antioxidant effects of Etlingera elatior flower extract against lead acetate - induced perturbations in free radical scavenging enzymes and lipid peroxidation in rats

    PubMed Central

    2011-01-01

    Background Etlingera elatior or 'pink torch ginger' (Zingiberaceae) are widely cultivated in tropical countries and used as spices and food flavoring. The purpose of this study was to evaluate the antioxidant effects of Etlingera elatior against lead - induced changes in serum free radical scavenging enzymes and lipid hydroperoxides in rats. Findings Rats were exposed to lead acetate in drinking water (500 ppm) for 14 days alone or plus the ethanol extract of E. elatior (50, 100 and 200 mg/kg). Blood lead levels, lipid hydroperoxides, protein carbonyl contents and oxidative marker enzymes were estimated. Lead acetate in drinking water elicited a significant increase in lipid hydroperoxides (LPO) and protein-carbonyl-contents (PCC). There was a significant decrease in total antioxidants, superoxide dismutase, glutathione peroxidase and glutathione S-transferase levels with lead acetate treatment. Supplementation of E. elatior was associated with reduced serum LPO and PCC and a significant increase in total antioxidants and antioxidant enzyme levels. Conclusions The results suggest that flower extract of Etlingera elatior has powerful antioxidant effect against lead - induced oxidative stress and the extract may be useful therapeutic agent against lead toxicity. However, detailed evaluations are required to identify the active antioxidant compounds from this plant extract. PMID:21414212

  9. Development of 2-(Substituted Benzylamino)-4-Methyl-1, 3-Thiazole-5-Carboxylic Acid Derivatives as Xanthine Oxidase Inhibitors and Free Radical Scavengers.

    PubMed

    Ali, Md Rahmat; Kumar, Suresh; Afzal, Obaid; Shalmali, Nishtha; Sharma, Manju; Bawa, Sandhya

    2016-04-01

    A series of 2-(substituted benzylamino)-4-methylthiazole-5-carboxylic acid was designed and synthesized as structural analogue of febuxostat. A methylene amine spacer was incorporated between the phenyl ring and thiazole ring in contrast to febuxostat in which the phenyl ring was directly linked with the thiazole moiety. The purpose of incorporating methylene amine was to provide a heteroatom which is expected to favour hydrogen bonding within the active site residues of the enzyme xanthine oxidase. The structure of all the compounds was established by the combined use of FT-IR, NMR and MS spectral data. All the compounds were screened in vitro for their ability to inhibit the enzyme xanthine oxidase as per the reported procedure along with DPPH free radical scavenging assay. Compounds 5j, 5k and 5l demonstrated satisfactory potent xanthine oxidase inhibitory activities with IC50 values, 3.6, 8.1 and 9.9 μm, respectively, whereas compounds 5k, 5n and 5p demonstrated moderate antioxidant activities having IC50 15.3, 17.6 and 19.6 μm, respectively, along with xanthine oxidase inhibitory activity. Compound 5k showed moderate xanthine oxidase inhibitory activity as compared with febuxostat along with antioxidant activity. All the compounds were also studied for their binding affinity in active site of enzyme (PDB ID-1N5X). PMID:26575582

  10. Evaluation of DNA binding, DNA cleavage, protein binding, radical scavenging and in vitro cytotoxic activities of ruthenium(II) complexes containing 2,4-dihydroxy benzylidene ligands.

    PubMed

    Mohanraj, Maruthachalam; Ayyannan, Ganesan; Raja, Gunasekaran; Jayabalakrishnan, Chinnasamy

    2016-12-01

    The new ruthenium(II) complexes with hydrazone ligands, 4-Methyl-benzoic acid (2,4-dihydroxy-benzylidene)-hydrazide (HL(1)), 4-Methoxy-benzoic acid (2,4-dihydroxy-benzylidene)-hydrazide (HL(2)), 4-Bromo-benzoic acid (2,4-dihydroxy-benzylidene)-hydrazide (HL(3)), were synthesized and characterized by various spectro analytical techniques. The molecular structures of the ligands were confirmed by single crystal X-ray diffraction technique. The DNA binding studies of the ligands and complexes were examined by absorption, fluorescence, viscosity and cyclic voltammetry methods. The results indicated that the ligands and complexes could interact with calf thymus DNA (CT-DNA) through intercalation. The DNA cleavage activity of the complexes was evaluated by gel electrophoresis assay, which revealed that the complexes are good DNA cleaving agents. The binding interaction of the ligands and complexes with bovine serum albumin (BSA) was investigated using fluorescence spectroscopic method. Antioxidant studies showed that the complexes have a strong radical scavenging properties. Further, the cytotoxic effect of the complexes examined on cancerous cell lines showed that the complexes exhibit significant anticancer activity. PMID:27612830

  11. Yerba mate (Ilex paraguariensis St. Hill.)-based beverages: How successive extraction influences the extract composition and its capacity to chelate iron and scavenge free radicals.

    PubMed

    Colpo, Ana C; Rosa, Hemerson; Lima, Maria Eduarda; Pazzini, Camila Eliza F; de Camargo, Vanessa B; Bassante, Felipa E M; Puntel, Robson; Ávila, Daiana Silva; Mendez, Andreas; Folmer, Vanderlei

    2016-10-15

    Chimarrão or mate is a popular beverage from South America that is drank with successive infusions. Although yerba mate extracts have been widely studied, few studies have described the extract contents in beverages. Using yerba mate samples from Brazil, Argentina, and Uruguay, we examined the extract chromatographic profiles, total polyphenol content and their capacities to chelate iron. In addition, we analyzed antioxidant activity by examining the ability of the extracts to scavenge DPPH and NO. Our results showed that the amount of extracted compound was highest in yerba mate extract from Uruguay, followed by Argentina, then Brazil. Herbs from all three areas had a significant capacity to inhibit DPPH and NO free radicals. The Brazilian and Uruguayan herbs had an 80% iron chelation capacity (p<0.001), while the iron chelation capacity of the Argentinean herb was lower but still significant (p⩽0.05). We conclude that the compound concentration decreases with successive extractions, while the antioxidant capacity is maintained at significant levels. PMID:27173551

  12. A newly developed hydroxyl radical scavenger, EPC-K1 can improve the survival of swine warm ischemia-damaged transplanted liver grafts.

    PubMed

    Yagi, T; Sakagami, K; Nakagawa, H; Takaishi, Y; Orita, K

    1992-01-01

    Using a swine orthotopic liver transplantation (SOLTx) model, we assessed the effect of a new hydroxyl radical scavenger EPC-K1 on warm ischemic damage of the liver graft and recipient survival. Animals were divided into 5 groups. The first group (control group 1) consisted of 5 pigs which were not operated on but served as controls for the indocianine green disappearance rate (K-ICG) determinations. In the second group (control group 2), 10 livers were transplanted without warm ischemia (WI) and the K-ICG values were measured. The third group (control group 3) was the main control group for the study groups and consisted of 5 liver transplants with 30 min of WI without any special treatment. The fourth and fifth groups served as study groups 1 and 2. Five transplants were carried out in each group, as in control group 3. In study group 1 recipients were treated with an additional 5 mg/kg i.v. EPC-K1 and in study group 2 with 20 mg/kg i.v. EPC-K1. Significant improvement in glutamic oxaloacetic transaminase (GOT) and lactate dehydrogenase (LDH) levels, K-ICG values and histological findings were observed in the EPC-K1 treated groups. The intravenous administration of this agent had a strong protective effect on warm ischemic damage after 30 min of WI and could significantly prolong the graft and recipient survival. PMID:14621836

  13. Phytochemicals of Salacia oblonga responsible for free radical scavenging and antiproliferative activity against breast cancer cell lines (MDA-MB-231).

    PubMed

    Musini, Anjaneyulu; Rao, Jayaram Prakash; Giri, Archana

    2015-10-01

    Salacia oblonga, an inhabitant of tropical regions has been used in traditional Indian medicinal systems. Phytochemicals were extracted in methanol from the plant and analyzed for various biological activities. The results of biochemical tests for total phenolics (297 ± 0.005 and 275 ± 0.006) and flavonoids (95 ± 0.004 and 61.6 ± 0.004) in the aerial and root parts were indicated as Gallic acid and quercetin equivalents respectively. The Aerial and root extracts showed strong reducing ability based on reducing power and FRAP assays. The extracts exhibited significant IC50 values in DPPH, super oxide and nitric oxide radical scavenging assays. The extracts displayed low IC50 values (<50 μg/ml) when assessed for antiproliferative activity against breast cancer cell lines using the MTT assay. GC-MS analysis of methanolic extracts have revealed the presence of compounds viz. n-Hexadecanoic acid, N-Methoxy-N-methylacetamide, Ursa-9(11), 12-dien-3-ol, Gamma-sitosterol etc., that might be potential candidates for the biological activity exhibited by the extract. PMID:26600684

  14. Expressed sequence tag survey of gene expression in the scab mite Psoroptes ovis--allergens, proteases and free-radical scavengers.

    PubMed

    Kenyon, F; Welsh, M; Parkinson, J; Whitton, C; Blaxter, M L; Knox, D P

    2003-05-01

    Psoroptes ovis, the causative agent of sheep scab, is an important ectoparasitic mite infecting sheep, goats and cattle. Infection is characterized by an extensive dermatitis, scab formation and intense itching. Initial focal lesions spread outwards, coalesce and may extend over the whole body. The host response to infestation has all the characteristics of an immediate-type hypersensitivity reaction but the mite antigens and allergens which initiate this response are almost completely undefined. Here, 507 randomly selected cDNAs derived from a mixed population of P. ovis were sequenced and the resultant nucleotide sequences subjected to Cluster analysis and Blast searches. This analysis yielded 280 clusters of which 49 had > 1 sequence with 24 showing significant Blast X homology to another protein in the databases. There were 231 sequences which appeared on one occasion and 109 of these showed significant Blast X homology to other sequences in the databases. This analysis identified homologues of 9 different types of allergens which have been characterized in other allergic conditions such as responses to house dust mites. It also identified a number of cysteine proteases which may contribute to lesion development as well as several free-radical scavenging enzymes which may protect the mite from host immune effector responses. PMID:12793649

  15. Isolation and identification of a potent radical scavenger (canolol) from roasted high erucic mustard seed oil from Nepal and its formation during roasting.

    PubMed

    Shrestha, Kshitij; Stevens, Christian V; De Meulenaer, Bruno

    2012-08-01

    Roasting of high erucic mustard (HEM) seed has been reported to give a typical flavor and increase the oxidative stability of the extracted oil. A potent radical scavenging compound was successfully isolated from roasted HEM seed oil in a single-step chromatographic separation using an amino solid-phase extraction column. Nuclear magnetic resonance and mass spectrometry spectra revealed the compound as 2,6-dimethoxy-4-vinylphenol (generally known as canolol), and its identity was fully confirmed by chemical synthesis. The formation of canolol during roasting was compared among HEM varieties (Brassica juncea, B. juncea var. oriental, Brassica nigra, and Sinapis alba) together with a low erucic rapeseed variety. HEM varieties were shown to produce less than one-third of canolol compared to rapeseed at similar roasting conditions. This observation was linked to a lower free sinapic acid content together with a lower loss of sinapic acid derivatives in the HEM varieties compared to rapeseed. Around 50% of the canolol formed in the roasted seed was shown to be extracted in the oil. Roasting of HEM seed before oil extraction was found to be a beneficial step to obtain canolol-enriched oil, which could improve the oxidative stability. PMID:22746294

  16. Synthesis, characterization and crystal structure of cobalt(III) complexes containing 2-acetylpyridine thiosemicarbazones: DNA/protein interaction, radical scavenging and cytotoxic activities.

    PubMed

    Manikandan, Rajendran; Viswanathamurthi, Periasamy; Velmurugan, Krishnaswamy; Nandhakumar, Raju; Hashimoto, Takeshi; Endo, Akira

    2014-01-01

    The synthesis, structure and biological studies of cobalt(III) complexes supported by NNS-tridentate ligands are reported. Reactions of 2-acetylpyridine N-substituted thiosemicarbazone (HL(1-3)) with [CoCl2(PPh3)2] resulted [Co(L(1-3))2]Cl (1-3) which were characterized by elemental analysis and various spectral studies. The molecular structure of the complex 1 has been determined by single crystal X-ray diffraction studies. In vitro DNA binding studies of complexes 1-3 carried out by fluorescence studies and the results revealed the binding of complexes to DNA via intercalation. The binding constant (Kb) values of complexes 1-3 from fluorescence experiments showed that the complex 3 has greater binding propensity for DNA. The DNA cleavage activity of the complexes 1 and 3 were ascertained by gel electrophoresis assay which revealed that the complexes are good DNA cleavage agents. Further, the interactions of the complexes with bovine serum albumin (BSA) were also investigated using fluorescence spectroscopic method, which showed that the complexes 1-3 could bind strongly with BSA. The antioxidant property of the complexes was evaluated to test their free-radical scavenging ability. Furthermore, in vitro cytotoxicity of the complexes against MCF-7 and A431 cell lines was assayed which showed higher activity and efficiently vanished the cancer cells even at low concentrations. PMID:24342132

  17. Free Radical Scavenging Activity: Antiproliferative and Proteomics Analyses of the Differential Expression of Apoptotic Proteins in MCF-7 Cells Treated with Acetone Leaf Extract of Diospyros lycioides (Ebenaceae)

    PubMed Central

    Pilane, M. C.; Bagla, V. P.; Mokgotho, M. P.; Mbazima, V.; Matsebatlela, T. M.; Ncube, I.; Mampuru, L.

    2015-01-01

    Breast cancer is the most common cancer in South Africa. The acetone leaf extract of Diospyros lycioides was evaluated qualitatively and quantitatively for its antioxidant potential using DPPH assay and nitric oxide radical scavenging effect, while the viability of MCF-7 cells was evaluated using the MTT. MCF-7 treated cells were stained with Hoechst 335258 dye and annexin-V-FITC to be evaluated for apoptotic effect of the extract, while mRNA expression levels of apoptotic genes were assessed by quantitative real-time PCR and deferential protein expression levels using 2D gel electrophoresis and mass spectrometry. Results revealed presence of antioxidant constituents in the extract. Extract was shown to be cytotoxic in a concentration- and time-dependent manner. Cytotoxicity was demonstrated to be due to apoptosis, with 70% of the extract-treated cells being annexin-V-positive/PI negative at 48 hours. The extract was also shown to upregulate the expression of p53 gene with concomitant downregulation of the Bcl-2 antiapoptotic gene while differentially expressed proteins were identified as enolase, pyruvate kinase, and glyceraldehyde-3-phosphate. The extract in this study was shown to induce apoptosis at an early stage which makes it an ideal source that can be explored for compounds that may be used in the treatment and management of cancer. PMID:26457109

  18. The role of supplemental ultraviolet-B radiation in altering the metabolite profile, essential oil content and composition, and free radical scavenging activities of Coleus forskohlii, an indigenous medicinal plant.

    PubMed

    Takshak, Swabha; Agrawal, S B

    2016-04-01

    The effects of supplemental ultraviolet-B (s-UV-B; 3.6 kJ m(-2) day(-1) above ambient) radiation were investigated on plant metabolite profile, essential oil content and composition, and free radical scavenging capacities of methanolic extracts of Coleus forskohlii (an indigenous medicinal plant) grown under field conditions. Essential oil was isolated using hydrodistillation technique while alterations in metabolite profile and oil composition were determined via gas chromatography-mass spectroscopy (GC-MS). Leaf and root methanolic extracts were investigated via various in vitro assays for their DPPH radical-, superoxide radical-, hydrogen peroxide-, hydroxyl radical-, and nitric oxide radical scavenging activities, ferrous ion chelating activity, and reducing power. Phytochemical analysis revealed the presence of alkaloids, anthocyanins, coumarins, flavonoids, glycosides, phenols, saponins, steroids, tannins, and terpenoids. Oil content was found to be reduced (by ∼7 %) in supplemental UV-B (s-UV-B) treated plants; the composition of the plant extracts as well as essential oil was also considerably altered. Methanolic extracts from treated plant organs showed more potency as free radical scavengers (their EC50 values being lower than their respective controls). Anomalies were observed in Fe(2+) chelating activity for both leaves and roots. The present study concludes that s-UV-B adversely affects oil content in C. forskohlii and also alters the composition and contents of metabolites in both plant extracts and oil. The results also denote that s-UV-B treated plant organs might be more effective in safeguarding against oxidative stress, though further studies are required to authenticate these findings. PMID:26681329

  19. Studies on the self-catalyzed Knoevenagel condensation, characterization, DPPH radical scavenging activity, cytotoxicity, and molecular properties of 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones using single crystal XRD and DFT techniques

    NASA Astrophysics Data System (ADS)

    Suresh Kumar, G. S.; Antony Muthu Prabhu, A.; Bhuvanesh, N.

    2014-10-01

    We have studied the self-catalyzed Knoevenagel condensation, spectral characterization, DPPH radical scavenging activity, cytotoxicity, and molecular properties of 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones using single crystal XRD and DFT techniques. In the absence of any catalyst, a series of novel 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones were synthesized using Meldrum’s acid and formylphenoxyaliphatic acid(s) in water. These molecules are arranged in the dimer form through intermolecular H-bonding in the single crystal XRD structure. Compounds have better DPPH radical scavenging activity and cytotoxicity against A431 cancer cell line. The optimized molecular structure, natural bond orbital analysis, electrostatic potential map, HOMO-LUMO energies, molecular properties, and atomic charges of these molecules have been studied by performing DFT/B3LYP/3-21G(*) level of theory in gas phase.

  20. Overview and Major Findings of the Study of Houston Atmospheric Radical Precursors (SHARP) Campaign

    NASA Astrophysics Data System (ADS)

    Lefer, B. L.; Brune, W. H.; Collins, D. R.; Dibb, J. E.; Griffin, R. J.; Herndon, S. C.; Huey, L. G.; Jobson, B. T.; Luke, W. T.; Mellqvist, J.; Morris, G. A.; Mount, G. H.; North, S. W.; Olaguer, E. P.; Rappenglueck, B.; Ren, X.; Stutz, J.; Yu, X.; Zhang, R.

    2010-12-01

    Despite recent improvements in Houston’s air quality, particularly in the reduction of the number of days with ozone mixing ratios with a 1-hr average of 125 ppbv or greater, the Houston-Galveston-Brazoria (HGB) metropolitan area still has approximately 30 days where 8-hr ozone levels exceed the 75 ppbv standard. More than a third of these high ozone episodes typically occur during the Springtime. Based on the 2006 TexAQS-II and TRAMP findings highlighting the importance of HONO, HCHO, and potentially ClNO2 as radical sources in the Houston atmosphere, the Study of Houston Atmospheric Radical Precursors (SHARP) 2009 project was designed to address the following goals: (1) determine the contribution of direct emissions of OH radical precursors HCHO and HONO from flares and other point and mobile sources; (2) detect the important urban formation pathways of HONO (day/night, surface, heterogeneous, homogeneous); (3) quantify the impact of soot (fresh and coated) on chemistry and radiation, (4) measure the ambient levels of ClNO2 in Houston and determine its’ potential as a radical source; (5) perform an intercomparison of ambient HONO measurement techniques in a urban environment; (6) identify the relative importance of springtime ozone formation mechanisms in Houston. The overall purpose of pursuing these objectives was to reduce the uncertainties surrounding these processes with the aim of improve our ability to model radicals and ozone formation in Houston and other coastal cities with petrochemical operations. The majority of the time the meteorological and chemical conditions during the 2009 SHARP campaign resulted in clean southerly flow from the Gulf of Mexico. This southerly flow was interrupted at least 4 times by cold front passages during the campaign. Each frontal passage resulted in an 8-hr ozone exceedance one to three days later. Significant findings from the SHARP project from 15 April to 30 May 2009 include: (a) measurements of HCHO emitted

  1. Antioxidant profile and in vitro cardiac radical-scavenging versus pro-oxidant effects of commercial red grape juices ( Vitis vinifera L. cv. Aglianico N.).

    PubMed

    Tenore, Gian Carlo; Manfra, Michele; Stiuso, Paola; Coppola, Luigi; Russo, Mariateresa; Gomez Monterrey, Isabel Maria; Campiglia, Pietro

    2012-09-26

    Several works have reported on the pharmaceutical usefulness of grape phytochemicals. Nevertheless, the scientific literature needs further studies to consider grape extracts as useful dietary supplements. The aim of the present work was to hypothesize for the first time the use of whole commercial red grape juices as food supplements potentially useful against both physiological and induced cardiac oxidative stress. First of all, the results indicated a good antioxidant stability of the juice sample to lyophilization that may be reasonably regarded as a suitable process for the formulation of food supplements. Then, the processed sample (lioRGJ) was tested on cardiac-derived H9C2 myocytes to ascertain its effects on reactive oxygen species (ROS) generation and caspase-3 activity incubating cardiomyocytes with lioRGJ at increasing doses (0.01-1 μg). Experiments showed an appreciable direct radical-scavenging activity at a maximum sample dose of 0.01 μg that made the caspase-3 activity decrease by about 47% (P < 0.001). Cardiac cells were exposed to 1 μM doxorubicin and its combination with different doses of lioRGJ. A maximum sample aliquot of 0.01 μg seemed to effectively contrast the induced oxidant injury, decreasing the ROS levels by about 31% and depressing the caspase-3 activity by about 60% (P < 0.001). In both assays, pro-oxidant effects at higher sample concentrations were detected as indicated by the increase in both ROS generation and apoptotic activity. The data suggested the possible employment of the juice sample as a food supplement with prospective cardioprotective benefits, although further studies are needed to optimize its dosages to avoid harmful pro-oxidant effects. PMID:22917058

  2. Biosynthesis of silver nanoparticles from Cavendish banana peel extract and its antibacterial and free radical scavenging assay: a novel biological approach

    NASA Astrophysics Data System (ADS)

    Kokila, T.; Ramesh, P. S.; Geetha, D.

    2015-11-01

    Biosynthesis of metallic silver nanoparticles has now become an alternative to physical and chemical approaches. In the present study, silver nanoparticles (AgNPs) were synthesized from Cavendish banana peel extract (CBPE) and characterized by UV-visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Atomic force microscopy (AFM), Field emission scanning electronic microscope (FESEM), Dynamic light scattering (DLS) and zeta potential (ZP). The AgNPs formation was confirmed by UV-visible spectroscopy through color conversion due to surface plasma resonance band at 430 nm. The effect of pH on nanoparticle synthesis was determined by adjusting the various pH of the reaction mixtures. The crystalline nature of nanoparticles was confirmed from the XRD pattern, and the grain size was found to be around 34 nm. To identify the compounds responsible for the bioreduction of Ag+ ion and the stabilization of AgNPs produced, the functional group present in Cavendish banana peel extract was investigated using FTIR. AFM has proved to be very helpful in determining morphological features and the diameter of AgNPs in the range of 23-30 nm was confirmed by FESEM. DLS studies revealed that the average size of AgNPs was found to be around 297 nm. Zeta potential value for AgNPs obtained was -11 mV indicating the moderate stability of synthesized nanoparticles. The antibacterial activity of the nanoparticles was studied against Gram-positive and Gram-negative bacteria. Biosynthesized AgNPs showed a strong DPPH radical and ABTS scavengers compared to the aqueous peel extract of Cavendish banana.

  3. The effect of meclofenoxate with ginkgo biloba extract or zinc on lipid peroxide, some free radical scavengers and the cardiovascular system of aged rats.

    PubMed

    al-Zuhair, H; Abd el-Fattah, A; el-Sayed, M I

    1998-07-01

    Aged rats are highly prone to many physiological changes such as blood pressure and heart rate. These changes could be due to modification in membrane phospholipid composition of their blood vessels. Lipid peroxide in vivo has been identified as a basic deteriorative reaction in cellular mechanisms of aging in human. The effect of a nootropic drug, meclofenoxate (MF) or its combination with extract of ginkgo biloba (EGb-761) or zinc (Zn) on malondialdehyde (MDA) product as an index of endogenous lipid peroxidation; phospholipid; glutathione (GSH) and protein thiols (PrSHs) contents as well as superoxide dismutase (SOD) activity in blood, brain, heart and liver of 24-month-old male rats was investigated. Aged rats were treated with MF once daily at oral doses of 100 mg kg-1 body wt. alone or with either EGb at a dose of 150 mg kg-1 body wt. or Zn at 10.5 mg kg-1 body wt. for 4 weeks. This study showed that aging caused a higher increment in MDA level of brain and heart than liver and plasma accompanied with reduction in brain and heart phospholipid contents as well as alteration of the antioxidant systems as compared to 4-month-old rats. Treatment of aged rats with MF alone or combined with either EGb or Zn caused improvement in the measured free radical scavengers especially in brain and heart tissues. Our results also showed that both EGb and Zn induced a significant potential effect of MF action on blood pressure and heart rate. The results were explained in the light of the antioxidant properties of EGb and Zn. Thus it is concluded that EGb and Zn have a beneficial role with MF in diminishing cumulative oxidative changes in aging. PMID:9697157

  4. Synthesis, characterization, DNA interactions, DNA cleavage, radical scavenging activity, antibacterial, anti-proliferative and docking studies of new transition metal complexes.

    PubMed

    Chennam, Kishan Prasad; Ravi, Mudavath; Ushaiah, B; Srinu, V; Eslavath, Ravi Kumar; Devi, Ch Sarala

    2016-01-01

    The compound N-(2-hydroxybenzylidene)-1-ethyl-1, 4-dihydro-7-methyl-4-oxo-1, 8 naphthyridine-3-carbohydrazide (LH) and its Cu (II), Co (II) and Zn (II) complexes were synthesized and characterized. The absorption spectral titrations and competitive DNA binding studies depicted those complexes of title compound bind to CT-DNA through intercalation. Interestingly [Cu (II)-(L2)] showed relatively high binding constant value (6.61 x 10(5) M(-1)) compared to [Co (II)-(L2)] (4.378× 10(5) M(-1)) and [Zn (II)-(L2)] (3.1x10(5) M(-1)). Ligand and its complexes were also examined for DNA nuclease activity against pBR-322 plasmid DNA, which showed that [Cu (II)-(L2)] had the best hydrolytic cleavage property displaying prominent double-strand DNA cleavage. In addition, antioxidant activities of the ligand and its metal complexes investigated through scavenging effects for DPPH radical in- vitro, indicated their potentiality as good antioxidants. The in vitro anti-bacterial study inferred the better anti-bacterial activity of [Cu (II)-(L2)] and this was also correlated theoretically by employing docking studies wherein [Cu (II)-(L2)] displayed good Gold score and Chem score. Finally the in vitro anti- proliferative activity of studied compounds was tested against HeLa and MCF-7 cell lines. Interestingly [Cu (II)-(L2)] displayed lower IC50 value and lower percentage of viability in both HeLa and MCF-7 cell lines. PMID:26545354

  5. Oxygen Radical Scavenger Activity, EPR, NMR, Molecular Mechanics and Extended-Hückel Molecular Orbital Investigation of the Bis(Piroxicam)Copper(II) Complex.

    PubMed

    Cini, R; Pogni, R; Basosi, R; Donati, A; Rossi, C; Sabadini, L; Rollo, L; Lorenzini, S; Gelli, R; Marcolongo, R

    1995-01-01

    The oxygen radical scavenger activity (ORSA) of [Cu(II)(Pir)(2)] (HPir = Piroxicam = 4-hydroxy -2- methyl -N-2- pyridyl -2H- 1,2-benzothiazine -3- carboxamide 1,1-dioxide) was determined by chemiluminescence of samples obtained by mixing human neutrophils (from healthy subjects) and [Cu(II)(Pir)(2)(DMF)(2)] (DMF = N,N -dimethylformammide) in DMSO/GLY/PBS (2:1:2, v/v) solution (DMSO = dimethylsulfoxide, GLY = 1,2,3-propantriol, PBS = Dulbecco's buffer salt solution). The ratio of the residual radicals, for the HPir (1.02.10(-4)M) and [Cu(II)(Pir)(2)(DMF)(2)] (1.08.10(-5)M)/HPir (8.01.10-(-5)M) systems was higher than 12 (not stimulated) [excess of piroxicam was added (Cu/Pir molar ratio approximately 1:10) in order to have most of the metal complexed as bischelate]. In contrast, the ratio of residual radicals for the CuCl(2) (1.00.10(-5)M) and [Cu(II)(Pir)(2)(DMF)(2)] (1.08.10(-5)M)/Hpir (8.01.10(-5)M)system was 5. The [Cu(II)(Pir)(2)] compound is therefore a stronger radical scavenger than either HPir or CuCl(2). A molecular mechanics (MM) analysis of the gas phase structures of neutral HPir, its zwitterionic (HPir(+-)) and anionic (Pir(-)) forms, and some Cu(II)-piroxicam complexes based on X-ray structures allowed calculation of force constants. The most stable structure for HPir has a ZZZ conformation similar to that found in the Cu(II) (and Cd(II) complexes) in the solid state as well as in the gas phase. The structure is stabilized by a strong H bond which involves the N(amide)-H and O(enolic) groups. The MM simulation for the [Cu(II)(Pir)(2)(DMF)(2)] complex showed that two high repulsive intramolecular contacts exist between a pyridyl hydrogen atom of one Pir(-) molecule with the O donor of the other ligand. These interactions activate a transition toward a pseudo-tetrahedral geometry, in the case the apical ligands are removed. On refluxing a suspension of [Cu(II)(Pir)(2)(DMF)(2)] in acetone a brown microcystalline solid with the Cu(Pir)(2).0.5DMF

  6. Rejoining of gamma-radiation-induced single-strand breaks in plasmid DNA by human cell extracts: Dependence on the concentration of the hydroxyl radical scavenger, Tris

    SciTech Connect

    Hodgkins, P.S.; Fairman, M.P.; O`Neill, P.

    1996-01-01

    The rejoining of single-strand breaks induced by {gamma} irradiation in plasmid DNA under different scavenging conditions is described using human cell extracts. As the scavenging capacity of the irradiated solution increases from 1.5 X 10{sup 7} to 3 X 10{sup 8} s{sup -1} using Tris-HCl as a scavenger, the ratio of single- to double-strand breaks is reduced from {approx}70:1 to 40:1. After irradiation, a proportion of DNA molecules have no initial strand breaks but contain damage that is converted to strand breaks when incubated either at 37{degrees}C or in the presence of cellular extract. Repair of damage by the extracts is dependent upon the scavenging capacity of the irradiated solution. Optimal rejoining is observed when the scavenging capacity is <1.5 X 10{sup 7} s{sup -1}, and results in the repair of some initial strand breaks. As the scavenging capacity increases to 3 X 10{sup 8} s{sup -1} the proportion of breaks repaired is significantly reduced. The relative increase in the yield of double-strand breaks and reduced repairability of single-strand breaks at a scavenging capacity of 3 X 10{sup 8} s{sup -1} is consistent with the concept that the severity of damage increases upon increasing the scavenger concentration. 26 refs., 5 figs., 1 tab.

  7. Salivary thiocyanate/nitrite inhibits hydroxylation of 2-hydroxybenzoic acid induced by hydrogen peroxide/Fe(II) systems under acidic conditions: possibility of thiocyanate/nitrite-dependent scavenging of hydroxyl radical in the stomach.

    PubMed

    Takahama, Umeo; Oniki, Takayuki

    2004-11-18

    Formation of OH radicals in the stomach is possible by Fenton-type reactions, as gastric juice contains ascorbic acid (AA), iron ions and H2O2. An objective of the present study is to elucidate the effects of salivary SCN- and NO2- on the hydroxylation of salicylic acid which was induced by H2O2/Fe(II) and AA/H2O2/Fe(II) systems. Thiocyanate ion inhibited the hydroxylation of salicylic acid by the above systems in acidic buffer solutions and in acidified saliva. The inhibition by SCN- was deduced to be due to SCN- -dependent scavenging of OH radicals. Nitrite ion could enhance the SCN- -dependent inhibition of the hydroxylation induced by AA/H2O2/Fe(II) systems. The enhancement was suggested to be due to scavenging of OH radicals by NO which was formed by the reactions among AA, HNO2 and SCN- contained in the reaction mixture. The concentrations of SCN- and NO2-, which were effective for the inhibition, were in ranges of their normal salivary concentrations. These results suggest that salivary SCN- can cooperate with NO2- to protect stomach from OH radicals formed by AA/H2O2/Fe(II) systems under acidic conditions. PMID:15535976

  8. In vitro propagation by asymbiotic seed germination and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity studies of tissue culture raised plants of three medicinally important species of dendrobium.

    PubMed

    Lo, Shu-Fung; Nalawade, Satish Manohar; Mulabagal, Vanisree; Matthew, Susan; Chen, Chung-Li; Kuo, Chao-Lin; Tsay, Hsin-Sheng

    2004-05-01

    A simple and efficient plant propagation system has been developed by asymbiotic germination of seeds in three medicinally important Dendrobium species, namely, Dendrobium tosaense, Dendrobium moniliforme, and Dendrobium linawianum. Plants obtained from natural habitats were grown in the greenhouse. The flowers were hand pollinated. Seeds of the capsules derived after 12 weeks of hand-pollination germinated asymbiotically (50-74%) on half strength Murashige and Skoog's (MS) basal medium with 3% sucrose and solidified with 0.9% Difco agar. Active growth in the germinated seedlings was achieved by re-culturing on full strength MS basal medium supplemented with 8% banana homogenate, 8% potato homogenate, 8% coconut water, 1.5% sucrose and 0.9% Difco agar. Healthy plantlets, transferred to plastic trays containing moss or moss and tree fern, successfully acclimatized (84-100%) in the greenhouse. A marked varied response was observed in the free radical scavenging activity of methanolic extracts of in vitro propagated plants, on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical using a UV spectrophotometer assay. Methanolic extracts were prepared by dissolving the powdered plant material, obtained from six months old in vitro propagated plants, each about 5 g, in boiling methanol. The percentage of scavenging effect of D. tosaense extract was 95.9% at 0.4 mg/ml concentration, whereas D. monoliforme, and D. linawianum extracts scavenged 83.4% and 92.3%, respectively, at a concentration of 0.4 mg/ml. All the extracts scavenged DPPH radical significantly in a concentration dependent manner. PMID:15133256

  9. Flavanoid-rich fraction from Sageretia theezans leaves scavenges reactive oxygen radical species and increases the resistance of low-density lipoprotein to oxidation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To explore their bioactive fractions, S. theezans leaves were extracted 2 with 60% acetone and then fractionated sequentially with hexane, ethyl acetate, and water. ROS (HOCl, ONOO-, and O2 deg -) scavenging activity, ORAC value and total phenolic content of each fraction were investigated. The ethy...

  10. Improved brain MRI indices in the acute brain stem infarct sites treated with hydroxyl radical scavengers, Edaravone and hydrogen, as compared to Edaravone alone. A non-controlled study

    PubMed Central

    2011-01-01

    Background In acute stage of cerebral infarction, MRI indices (rDWI & rADC) deteriorate during the first 3-7 days after the ictus and then gradually normalize in approximately 10 days (pseudonormalization time), although the tissue is already infarcted. Since effective treatments improve these indices significantly and in less than the natural pseudonormalization time, a combined analysis of these changes provides an opportunity for objective evaluation on the effectiveness of various treatments for cerebral infarction. Hydroxyl radicals are highly destructive to the tissue and aggravate cerebral infarction. We treated brainstem infarction patients in acute stage with hydroxyl radical scavengers (Edaravone and hydrogen) by intravenous administration and evaluated the effects of the treatment by a serial observation and analysis of these MRI indices. The effects of the treatment were evaluated and compared in two groups, an Edaravone alone group and a combined group with Edaravone and hydrogen, in order to assess beneficial effects of addition of hydrogen. Methods The patients were divided in Edaravone only group (E group. 26 patients) and combined treatment group with Edaravone and hydrogen enriched saline (EH group. 8 patients). The extent of the initial hump of rDWI, the initial dip of rADC and pseudo-normalization time were determined in each patient serially and averages of these data were compared in these two groups and also with the natural course in the literatures. Results The initial hump of rDWI reached 2.0 in the E group which was better than 2.5 of the natural course but was not as good as 1.5 of the EH group. The initial dip of rADC was 0.6 in the E group which was close to the natural course but worse than 0.8 of the EH group. Pseudonormalization time of rDWI and rADC was 9 days only in EH group but longer in other groups. Addition of hydrogen caused no side effects. Conclusions Administration of hydroxyl radical scavengers in acute stage of

  11. Non-covalent interaction between dietary stilbenoids and human serum albumin: Structure-affinity relationship, and its influence on the stability, free radical scavenging activity and cell uptake of stilbenoids.

    PubMed

    Cao, Hui; Jia, Xueping; Shi, Jian; Xiao, Jianbo; Chen, Xiaoqing

    2016-07-01

    Dietary stilbenoids are associated with many benefits for human health, which depend on their bioavailability and bioaccessibility. The stilbenoid-human serum albumin (HSA) interactions are investigated to explore the structure-affinity relationship and influence on the stability, free radical scavenging activity and cell uptake of stilbenoids. The structure-affinity relationship of the stilbenoids-HSA interaction was found as: (1) the methoxylation enhanced the affinity, (2) an additional hydroxyl group increases the affinity and (3) the glycosylation significantly weakened the affinity. HSA obviously masked the free radical scavenging potential of stilbenoids. The stabilities of stilbenoids in different medium were determined as: HSA solution>human plasma>Dulbecco's modified Eagle's medium. It appears that the milk enhanced the cell uptake of stilbenoids with multi-hydroxyl groups and weakened the cell uptake of stilbenoids with methoxyl group on EA.hy 926 endothelial cells. The stilbenoids are hardly absorbed by human umbilical vein endothelial cells in the presence of milk. PMID:26920308

  12. A Modified Method for Studying Behavioral Paradox of Antioxidants and Their Disproportionate Competitive Kinetic Effect to Scavenge the Peroxyl Radical Formation

    PubMed Central

    Masood, Nusrat; Fatima, Kaneez; Luqman, Suaib

    2014-01-01

    We have described a modified method for evaluating inhibitor of peroxyl radicals, a well-recognized and -documented radical involved in cancer initiation and promotion as well as diseases related to oxidative stress and ageing. We are reporting hydrophilic and lipophilic as well as natural and synthetic forms of antioxidants revealing a diversified behaviour to peroxyl radical in a dose-dependent manner (1 nM–10 μM). A simple kinetic model for the competitive oxidation of an indicator molecule (ABTS) and a various antioxidant by a radical (ROO•) is described. The influences of both the concentration of antioxidant and duration of reaction (70 min) on the inhibition of the radical cation absorption are taken into account while determining the activity. The induction time of the reaction was also proposed as a parameter enabling determination of antioxidant content by optimizing and introducing other kinetic parameters in 96-well plate assays. The test evidently improves the original PRTC (peroxyl radical trapping capacity) assay in terms of the amount of chemical used, simultaneous tracking, that is, the generation of the radical taking place continually and the kinetic reduction technique (area under curve, peak value, slope, and Vmax). PMID:24672395

  13. Simultaneous quantification of ten constituents of Xanthoceras sorbifolia Bunge using UHPLC-MS methods and evaluation of their radical scavenging, DNA scission protective, and α-glucosidase inhibitory activities.

    PubMed

    Zhang, Yu; Ma, Jian-Nan; Ma, Chun-Li; Qi, Zhi; Ma, Chao-Mei

    2015-11-01

    The present study was designed to investigate the bioactive constituents of Xanthoceras sorbifolia in terms of amounts and their antioxidant, DNA scission protection, and α-glucosidase inhibitory activities. Simultaneous quantification of 10 X. sorbifolia constituents was carried out by a newly established ultra-high performance liquid chromatography-quadrupole mass spectrometry method (UHPLC-MS). The antioxidant activities were evaluated by measuring DPPH radical scavenging and DNA scission protective activities. The α-glucosidase inhibitory activities were investigated by using an assay with α-glucosidase from Bacillus Stearothermophilus and disaccharidases from mouse intestine. We found that the wood of X. sorbifolia was rich in phenolic compounds with the contents of catechin, epicatechin, myricetin, and dihydromyricetin being 0.12-0.19, 1.94-2.16, 0.77-0.91, and 6.76-7.89 mg·g(-1), respectively. The four constituents strongly scavenged DPPH radicals (with EC50 being 4.2, 3.8 and 5.7 μg·mL(-1), respectively) and remarkably protected peroxyl radical-induced DNA strand scission (92.10%, 94.66%, 75.44% and 89.95% of protection, respectively, at a concentration of 10 μmol·L(-1)). A dimeric flavan 3-ol, epigallocatechin-(4β→8, 2β→O-7)-epicatechin potently inhibited α-glucosidase with an IC50 value being as low as 1.2 μg·mL(-1). The established UHPLC-MS method could serve as a quality control tool for X. sorbifolia. In conclusion, the high contents of antioxidant and α-glucosidase inhibitory constituents in X. sorbifolia support its use as complementation of other therapeutic agents for metabolic disorders, such as diabetes and hypertension. PMID:26614463

  14. Molecular structure, quantum mechanical calculation and radical scavenging activities of (E)-4,6-dibromo-2-[(3,5-dimethylphenylimino)methyl]-3-methoxyphenol and (E)-4,6-dibromo-2-[(2,6-dimethylphenylimino)methyl]-3-methoxyphenol compounds

    NASA Astrophysics Data System (ADS)

    Alaşalvar, Can; Soylu, Mustafa Serkan; Güder, Aytaç; Albayrak, Çiğdem; Apaydın, Gökhan; Dilek, Nefise

    2014-09-01

    In this study, (E)-4,6-dibromo-2-[(3,5-dimethylphenylimino)methyl]-3-methoxyphenol and (E)-4,6-dibromo-2-[(2,6-dimethylphenylimino)methyl]-3-methoxyphenol compounds have been synthesized and characterized by using X-ray crystallographic method, FT-IR and Density functional method. The molecular geometry, vibrational frequencies of the title compounds in the ground state have been calculated by using B3LYP with the 6-31G(d,p) basis set. The tautomeric form of the compounds has been demonstrated by using single crystal X-ray method, FT-IR spectrometer and DFT method. In addition, HOMO-LUMO energy gap, molecular electrostatic potential map and NBO analysis of the compounds are performed at B3LYP/6-31G(d,p) level. It may be remarked that the free radical scavenging activities of the title compounds were assessed using DPPHrad , DMPDrad +, and ABTSrad + assays. The obtained results show that especially compound 2 has effective DPPHrad (SC50 1.52 ± 0.14 μg/mL), DMPDrad + (SC50 1.22 ± 0.21 μg/mL), and ABTSrad + (SC50 3.32 ± 0.17 μg/mL) scavenging activities compared with standards (BHA, rutin, and trolox).

  15. Hydrogen scavengers

    SciTech Connect

    Carroll, David W.; Salazar, Kenneth V.; Trkula, Mitchell; Sandoval, Cynthia W.

    2002-01-01

    There has been invented a codeposition process for fabricating hydrogen scavengers. First, a .pi.-bonded allylic organometallic complex is prepared by reacting an allylic transition metal halide with an organic ligand complexed with an alkali metal; and then, in a second step, a vapor of the .pi.-bonded allylic organometallic complex is combined with the vapor of an acetylenic compound, irradiated with UV light, and codeposited on a substrate.

  16. DPPH radical scavenging activity of a mixture of fatty acids and peptide-containing compounds in a protein hydrolysate of Jatropha curcas seed cake.

    PubMed

    Phengnuam, Thanyarat; Goroncy, Alexander K; Rutherfurd, Shane M; Moughan, Paul J; Suntornsuk, Worapot

    2013-12-01

    Jatropha curcas, a tropical plant, has great potential commercial relevance as its seeds have high oil content. The seeds can be processed into high-quality biofuel producing seed cake as a byproduct. The seed cake, however, has not gotten much attention toward its potential usefulness. This work was aimed to determine the antioxidant activity of different fractions of a protein hydrolysate from J. curcas seed cake and to elucidate the molecular structures of the antioxidants. Seed cake was first processed into crude protein isolate and the protein was hydrolyzed by Neutrase. The hydrolysate obtained from 1 h of Neutrase hydrolysis showed the strongest antioxidant activity against DPPH radical (2,2-diphenyl-1-picrylhydrazyl). After a purification series of protein hydrolysate by liquid chromatography, chemicals acting as DPPH radical inhibitors were found to be a mixture of fatty acids, fatty acid derivatives, and a small amount of peptides characterized by mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy. PMID:24191657

  17. Synthesis, structural and spectroscopic characterization and biomimetic properties of new copper, manganese, zinc complexes: identification of possible superoxide-dismutase mimics bearing hydroxyl radical generating/scavenging abilities.

    PubMed

    Lupidi, Giulio; Marchetti, Fabio; Masciocchi, Norberto; Reger, Daniel L; Tabassum, Sartaj; Astolfi, Paola; Damiani, Elisabetta; Pettinari, Claudio

    2010-08-01

    A series of Cu(II), Zn(II) and Mn(II) coordination compounds has been synthesized by reaction of the corresponding metal salts and pyrazolyl-based ligands, i.e. the neutral 1-(2-(4-((2,2,2-tri(1H-pyrazol-1-yl)ethoxy)methyl)benzyloxy)-1,1-di(1H-pyrazol-1-yl)ethyl)-1H-pyrazole {p-C(6)H(4)[CH(2)OCH(2)C(pz)(3)](2), (L(1)), and the anionic hydridotris(3-phenyl-5-methylpyrazolyl)borate (L(2))(-), bis(pyrazolyl)acetate (L(3)) and bis(3,5-dimethylpyrazolyl)acetate (L(4))(-): the species [L(1)(CuCl(2))(2)] (1), [L(1)(Cu(OAc)(2))(2)] (2), [L(1)(Zn(OAc)(2))(2)] (3), [(CuCl(L(2))(Hpz(Ph,Me))] (4), [Mn(L(3))(2)].2H(2)O, (5), [ZnCl(L(3))(imH)].MeOH [CuCl(L(4))(imH)].2H(2)O (7) have been obtained (Hpz(Ph,Me)=3-phenyl-5-methylpyrazole, imH=imidazole). Complexes 1 and 4 have been structurally characterized, also using less conventional powder diffraction methods. The superoxide scavenging activity has been characterized by indirect assays including EPR analysis. All complexes exhibit superoxide scavenging activity with IC(50) in the microM range and they protect against the oxidative action of peroxynitrite in different ways. 1, 4 and 7 exert both an anti- and pro-oxidant effect depending on their concentration as evaluated by EPR and fluorescence methods. The pro-oxidative effects are absent in Zn(II) and Mn(II) complexes. PMID:20452028

  18. Melatonin mediates the regulation of ABA metabolism, free-radical scavenging, and stomatal behaviour in two Malus species under drought stress.

    PubMed

    Li, Chao; Tan, Dun-Xian; Liang, Dong; Chang, Cong; Jia, Dongfeng; Ma, Fengwang

    2015-02-01

    Melatonin pre-treatment significantly increases the tolerance of both drought-tolerant Malus prunifolia and drought-sensitive M. hupehensis plants. Its beneficial effects include better water conservation in leaves, less electrolyte leakage, steady chlorophyll contents, and greater photosynthetic performance under stress conditions. Melatonin selectively down-regulates MdNCED3, an abscisic acid (ABA) synthesis gene, and up-regulates its catabolic genes, MdCYP707A1 and MdCYP707A2, thereby reducing ABA contents in drought-stressed plants. Melatonin also directly scavenges H2O2 and enhances the activities of antioxidant enzymes to detoxify H2O2 indirectly. These two mechanisms work synergistically to improve the functions of stomata, i.e. causing them to re-open. Plants can effectively regulate their water balance under drought conditions by up-regulating the expression of melatonin synthesis genes MdTDC1, MdAANAT2, MdT5H4, and MdASMT1. Therefore, inducing melatonin production is an important mechanism by which plants can counteract the influence of this abiotic stressor. PMID:25481689

  19. On the vasoprotective mechanisms underlying novel β-phosphorylated nitrones: Focus on free radical characterization, scavenging and NO-donation in a biological model of oxidative stress.

    PubMed

    Cassien, Mathieu; Petrocchi, Consuelo; Thétiot-Laurent, Sophie; Robin, Maxime; Ricquebourg, Emilie; Kandouli, Chouaib; Asteian, Alice; Rockenbauer, Antal; Mercier, Anne; Culcasi, Marcel; Pietri, Sylvia

    2016-08-25

    A series of new hybrid 2-(diethoxyphosphoryl)-N-(benzylidene)propan-2-amine oxide derivatives with different aromatic substitution (PPNs) were synthesized. These molecules were evaluated for their EPR spin trapping potential on eleven different radicals and NO-donation properties in vitro, cytotoxicity and vasoprotective effect on precontracted rat aortic rings. A subfamily of the new PPNs featured an antioxidant moiety occurring in natural phenolic acids. From the experimental screening of these hydroxyphenyl- and methoxyphenyl-substituted PPNs, biocompatible nitrones 4d, and 4g-4i deriving from caffeic, gallic, ferulic and sinapic acids, which combined improved EPR probing of ROS formation, vasorelaxant action and antioxidant potency, might be potential drug candidate alternatives to PBN and its analogues. PMID:27162124

  20. Protection against oxidative damage to CNS by alpha-phenyl-tert-butyl nitrone (PBN) and other spin-trapping agents: A novel series of nonlipid free radical scavengers

    SciTech Connect

    Carney, J.M.; Floyd, R.A. )

    1991-01-01

    Brain is extremely susceptible to oxidative damage. Utilizing a series of novel approaches, the authors have demonstrated that oxidative damage occurs during an ischemia/reperfusion insult (IRI) to brain. Thus, they have demonstrated that an IRI to Mongolian gerbil brain results in: (1) an enhanced rate of salicylate hydroxylation, implicating an increased flux of hydroxyl free radicals; (2) an enhanced flux of free radicals as determined by spin-trapping; (3) an enhanced level of endogenous protein oxidation; (4) a decrease in glutamine synthetase (GS) activity, an enzyme very sensitive to oxidative damage; and (5) demonstration of protection from an IRI by administering the spin-trapping agent alpha-phenyl-tert-butyl nitrone (PBN). The novel observation that PBN offers protection from the lethality brought on by a brain IRI appears to be clearly linked to the ability of the administered spin-trap to inhibit oxidative damage as evidenced by the decreased amount of brain protein oxidation and the prevention of an IRI-mediated loss of GS activity in treated animals. Aged gerbils are more sensitive to the lethal action of a brain IRI than younger animals, but they are protected by PBN administration as are the younger animals. Older gerbils have a significantly higher level of oxidized protein in the brain. Older gerbils have decreased activities of GS and neutral protease, the enzyme that removes oxidized protein, than younger animals. Chronic twice daily administration of PBN (32 mg/kg) for 14 days to older animals significantly lowered brain oxidized protein levels and raised GS and neutral protease activity to those observed in younger animals. Cessation of PBN administration resulted in a time-dependent restoration of protein oxidation levels and enzyme activities back to those observed prior to spin-trap administration.

  1. Alteration of Gene Expression, DNA Methylation, and Histone Methylation in Free Radical Scavenging Networks in Adult Mouse Hippocampus following Fetal Alcohol Exposure

    PubMed Central

    Chater-Diehl, Eric J.; Castellani, Christina A.; Alberry, Bonnie L.; Singh, Shiva M.

    2016-01-01

    The molecular basis of Fetal Alcohol Spectrum Disorders (FASD) is poorly understood; however, epigenetic and gene expression changes have been implicated. We have developed a mouse model of FASD characterized by learning and memory impairment and persistent gene expression changes. Epigenetic marks may maintain expression changes over a mouse’s lifetime, an area few have explored. Here, mice were injected with saline or ethanol on postnatal days four and seven. At 70 days of age gene expression microarray, methylated DNA immunoprecipitation microarray, H3K4me3 and H3K27me3 chromatin immunoprecipitation microarray were performed. Following extensive pathway analysis of the affected genes, we identified the top affected gene expression pathway as “Free radical scavenging”. We confirmed six of these changes by droplet digital PCR including the caspase Casp3 and Wnt transcription factor Tcf7l2. The top pathway for all methylation-affected genes was “Peroxisome biogenesis”; we confirmed differential DNA methylation in the Acca1 thiolase promoter. Altered methylation and gene expression in oxidative stress pathways in the adult hippocampus suggests a novel interface between epigenetic and oxidative stress mechanisms in FASD. PMID:27136348

  2. Chemical repair activity of free radical scavenger edaravone: reduction reactions with dGMP hydroxyl radical adducts and suppression of base lesions and AP sites on irradiated plasmid DNA

    PubMed Central

    Hata, Kuniki; Urushibara, Ayumi; Yamashita, Shinichi; Lin, Mingzhang; Muroya, Yusa; Shikazono, Naoya; Yokoya, Akinari; Fu, Haiying; Katsumura, Yosuke

    2015-01-01

    Reactions of edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) with deoxyguanosine monophosphate (dGMP) hydroxyl radical adducts were investigated by pulse radiolysis technique. Edaravone was found to reduce the dGMP hydroxyl radical adducts through electron transfer reactions. The rate constants of the reactions were greater than 4 × 108 dm3 mol−1 s−1 and similar to those of the reactions of ascorbic acid, which is a representative antioxidant. Yields of single-strand breaks, base lesions, and abasic sites produced in pUC18 plasmid DNA by gamma ray irradiation in the presence of low concentrations (10–1000 μmol dm−3) of edaravone were also quantified, and the chemical repair activity of edaravone was estimated by a method recently developed by the authors. By comparing suppression efficiencies to the induction of each DNA lesion, it was found that base lesions and abasic sites were suppressed by the chemical repair activity of edaravone, although the suppression of single-strand breaks was not very effective. This phenomenon was attributed to the chemical repair activity of edaravone toward base lesions and abasic sites. However, the chemical repair activity of edaravone for base lesions was lower than that of ascorbic acid. PMID:25212600

  3. Peroxynitrite scavenging by different antioxidants. Part I: convenient assay.

    PubMed

    Balavoine, G G; Geletii, Y V

    1999-01-01

    A convenient "tube" assay to quantify relative antioxidant activities in aqueous solutions has been developed. Peroxynitrite was employed as a biologically relevant source of radicals with Pyrogallol Red as a detecting molecule. A variety of compounds have been examined, namely polyphenols, uric acid, glutathione, and ascorbic acid. Competition kinetics were observed for the majority of examined compounds, except thymol and ascorbic acid. Pyrogallol Red was fully protected by ascorbic acid against the bleaching by peroxynitrite until its total consumption. The deviation from competition kinetics in the case of thymol was due to the formation of radicals from thymol and their subsequent reaction with Pyrogallol Red. Quercetin was the most efficient scavenger of free radicals. The measurements of relative antioxidant activities using Pyrogallol Red and other detecting molecules, such as gallocyanine and carminic acid, were in fair agreement. The assay was successfully used for a screening of antioxidant activity of plant extracts of unknown composition. PMID:10355895

  4. Free Radicals Scavenging Capacity, Antidiabetic and Antihypertensive Activities of Flavonoid-Rich Fractions from Leaves of Trichilia emetica and Opilia amentacea in an Animal Model of Type 2 Diabetes Mellitus.

    PubMed

    Konaté, Kiessoun; Yomalan, Kassi; Sytar, Oksana; Zerbo, Patrice; Brestic, Marian; Patrick, Van Damme; Gagniuc, Paul; Barro, Nicolas

    2014-01-01

    Trichilia emetica and Opilia amentacea traditional Burkinabe medicinal plants were investigated to determine their therapeutic potential to inhibit key enzymes in carbohydrate metabolism, which has relevance to the management of type 2 diabetes. In vitro and in vivo antioxidant and antihypertensive potential and antilipidemia and antihyperglycemia activities in an animal model of type 2 diabetes mellitus have been studied. The antioxidant activity of the flavonoids from leaves of Trichilia emetica and Opilia amentacea has been evaluated using β -carotene-linoleic acid system, 1,1-diphenyl-2-picrylhydrazyl inhibitory activity, chelation of iron (II) ions, and lipid peroxidation which showed more pronounced antioxidant capacities of Trichilia emetica. Total cholesterol concentrations decreased in an animal model of type 2 diabetes mellitus under effects of flavonoid-rich fractions from leaves of Trichilia emetica and Opilia amentacea has been observed. Extract of flavonoid-rich fractions from Trichilia emetica shown maximum radical scavenging activity and possessed marked antiamylase activity which may be due to the presence of certain secondary metabolites. Suggested better antihyperglycemia, antilipidemia, and antihypertensive properties of flavonoid-rich fractions from Trichilia emetica compared to the extract of Opilia amentacea are demonstrating antidiabetic potential of Trichilia emetica as therapeutic targets for the management of type 2 diabetes. PMID:24616741

  5. Free Radicals Scavenging Capacity, Antidiabetic and Antihypertensive Activities of Flavonoid-Rich Fractions from Leaves of Trichilia emetica and Opilia amentacea in an Animal Model of Type 2 Diabetes Mellitus

    PubMed Central

    Konaté, Kiessoun; Yomalan, Kassi; Sytar, Oksana; Zerbo, Patrice; Patrick, Van Damme; Gagniuc, Paul; Barro, Nicolas

    2014-01-01

    Trichilia emetica and Opilia amentacea traditional Burkinabe medicinal plants were investigated to determine their therapeutic potential to inhibit key enzymes in carbohydrate metabolism, which has relevance to the management of type 2 diabetes. In vitro and in vivo antioxidant and antihypertensive potential and antilipidemia and antihyperglycemia activities in an animal model of type 2 diabetes mellitus have been studied. The antioxidant activity of the flavonoids from leaves of Trichilia emetica and Opilia amentacea has been evaluated using β-carotene-linoleic acid system, 1,1-diphenyl-2-picrylhydrazyl inhibitory activity, chelation of iron (II) ions, and lipid peroxidation which showed more pronounced antioxidant capacities of Trichilia emetica. Total cholesterol concentrations decreased in an animal model of type 2 diabetes mellitus under effects of flavonoid-rich fractions from leaves of Trichilia emetica and Opilia amentacea has been observed. Extract of flavonoid-rich fractions from Trichilia emetica shown maximum radical scavenging activity and possessed marked antiamylase activity which may be due to the presence of certain secondary metabolites. Suggested better antihyperglycemia, antilipidemia, and antihypertensive properties of flavonoid-rich fractions from Trichilia emetica compared to the extract of Opilia amentacea are demonstrating antidiabetic potential of Trichilia emetica as therapeutic targets for the management of type 2 diabetes. PMID:24616741

  6. Antioxidant components of Viburnum opulus L. determined by on-line HPLC-UV-ABTS radical scavenging and LC-UV-ESI-MS methods.

    PubMed

    Karaçelik, Ayça Aktaş; Küçük, Murat; İskefiyeli, Zeynep; Aydemir, Sezgin; De Smet, Seppe; Miserez, Bram; Sandra, Patrick

    2015-05-15

    Antioxidant activity of the juice and seed and skin extracts prepared with methanol, acetonitrile, and water of Viburnum opulus L. grown in Eastern Black Sea Region were studied with an on-line HPLC-ABTS method and off-line antioxidant methods, among which a linear positive correlation was observed. The fruit extracts were analysed with the HPLC-UV method optimised with 14 standard phenolics. Identification of the phenolic components in the juice was made using an HPLC-UV-ESI-MS method. Nineteen phenolic compounds in juice were identified by comparing the retention times and mass spectra with those of the standards and the phenolics reported in the literature. The major peaks in the juice belonged to coumaroyl-quinic acid, chlorogenic acid, procyanidin B2, and procyanidin trimer. Quite different antioxidant composition profiles were obtained from the extracts with the solvents of different polarities. The antioxidant activities of the seed extracts were higher than those of the skin extracts in general. PMID:25577058

  7. Free Radical-Scavenging, Anti-Inflammatory/Anti-Fibrotic and Hepatoprotective Actions of Taurine and Silymarin against CCl4 Induced Rat Liver Damage

    PubMed Central

    Abdel-Moneim, Ashraf M.; Al-Kahtani, Mohammed A.; El-Kersh, Mohamed A.; Al-Omair, Mohammed A.

    2015-01-01

    The present study aims to investigate the hepatoprotective effect of taurine (TAU) alone or in combination with silymarin (SIL) on CCl4-induced liver damage. Twenty five male rats were randomized into 5 groups: normal control (vehicle treated), toxin control (CCl4 treated), CCl4+TAU, CCl4+SIL and CCl4+TAU+SIL. CCl4 provoked significant increases in the levels of hepatic TBARS, NO and NOS compared to control group, but the levels of endogenous antioxidants such as SOD, GPx, GR, GST and GSH were significantly decreased. Serum pro-inflammatory and fibrogenic cytokines including TNF-α, TGF-β1, IL-6, leptin and resistin were increased while the anti-inflammatory (adiponectin) cytokine was decreased in all treated rats. Our results also showed that CCl4 induced an increase in liver injury parameters like serum ALT, AST, ALP, GGT and bilirubin. In addition, a significant increase in liver tissue hydroxyproline (a major component of collagen) was detected in rats exposed to CCl4. Moreover, the concentrations of serum TG, TC, HDL-C, LDL-C, VLDL-C and FFA were significantly increased by CCl4. Both TAU and SIL (i.e., antioxidants) post-treatments were effectively able to relieve most of the above mentioned imbalances. However, the combination therapy was more effective than single applications in reducing TBARS levels, NO production, hydroxyproline content in fibrotic liver and the activity of serum GGT. Combined treatment (but not TAU- or SIL-alone) was also able to effectively prevent CCl4-induced decrease in adiponectin serum levels. Of note, the combined post-treatment with TAU+SIL (but not monotherapy) normalized serum FFA in CCl4-treated rats. The biochemical results were confirmed by histological and ultrastructural changes as compared to CCl4-poisoned rats. Therefore, on the basis of our work, TAU may be used in combination with SIL as an additional adjunct therapy to cure liver diseases such as fibrosis, cirrhosis and viral hepatitis. PMID:26659465

  8. Mechanism of reduction of bis(2-hydroxyethyl) trisulfide by e/sub aq//sup -/ and. CO/sub 2//sup -/. Spectrum and scavenging of RSS. radicals. [Electron beams and gamma rays

    SciTech Connect

    Wu, Z.; Back, T.G.; Ahmad, R.; Yamdagni, R.; Armstrong, D.A.

    1982-10-28

    Each of the reducing radicals e/sub aq//sup -/, .CO/sub 2//sup -/, and (CH/sub 3/)/sub 2/COH cleaves bis(2-hydroxyethyl) trisulfide in aqueous solution to produce (2-hydroxyethyl)perthiyl (RSS.) radicals and 2-hydroxyethanethiol. The RSS. radical had lambda/sub max/ = 374 nm, epsilon/sub max/ = 1630 +- 50 M/sup -1/ cm/sup -1/, and a second-order rate constant for dimerization 2k/sub 12/ = (1.4 +- 0.3) x 10/sup 9/ M/sup -1/s/sup -1/ (2RSS. ..-->.. RS/sub 4/R (12)). It is able to abstract H atoms from dihydroflavin adenine dinucleotide (FH/sub 2/), but not from formate. Thus, in aqueous solution D/sub RSS-H/ must be greater than 60 but less than 90 kcal mol/sup -1/. Although tetrasulfide and thiol are the major initial products of reduction, secondary thermal reactions occur and produce sulfanes (RS/sub n/H) and polysulfides (RS/sub n/R). In the early stages of reduction products of n = 2 dominate. However, on prolonged reaction with .CO/sub 2//sup -/ elemental sulfur is precipitated, and this is probably formed by elimination from sulfanes with n much larger and in the region of 8.

  9. The Scientist Scavenger Hunt.

    ERIC Educational Resources Information Center

    Morphew, Valerie N.; Key, Kathleen

    1994-01-01

    Using a well-planned scavenger hunt, students' awareness of the significance of minorities and women in science is enhanced. Provides a sample scavenger hunt and resource list as well as activities for extension. (ZWH)

  10. Radical prostatectomy

    MedlinePlus

    Prostatectomy - radical; Radical retropubic prostatectomy; Radical perineal prostatectomy; Laparoscopic radical prostatectomy; LRP; Robotic-assisted laparoscopic prostatectomy; RALP; Pelvic lymphadenectomy; ...

  11. Scavenging for the Past.

    ERIC Educational Resources Information Center

    McMahon, Sue; Strubbe, Mary

    1988-01-01

    Discusses the goals and planning of a scavenger hunt which was designed to increase enthusiasm in students and promote active learning. States that a scavenger hunt instills a sense of community pride in students and that the community cooperation fosters a positive relationship with the school. Provides a sample scavenger hunt checklist. (GEA)

  12. Glutamate neurotoxicity in rat cerebellar granule cells: a major role for xanthine oxidase in oxygen radical formation.

    PubMed

    Atlante, A; Gagliardi, S; Minervini, G M; Ciotti, M T; Marra, E; Calissano, P

    1997-05-01

    To gain insight into the mechanism through which the neurotransmitter glutamate causally participates in several neurological diseases, in vitro cultured cerebellar granule cells were exposed to glutamate and oxygen radical production was investigated. To this aim, a novel procedure was developed to detect oxygen radicals; the fluorescent dye 2',7'-dichlorofluorescein was used to detect production of peroxides, and a specific search for the possible conversion of the enzyme xanthine dehydrogenase into xanthine oxidase after the excitotoxic glutamate pulse was undertaken. A 100 microM glutamate pulse administered to 7-day-old cerebellar granule cells is accompanied by the onset of neuronal death, the appearance of xanthine oxidase, and production of oxygen radicals. Xanthine oxidase activation and superoxide (O2.-) production are completely inhibited by concomitant incubation of glutamate with MK-801, a specific NMDA receptor antagonist, or by chelation of external calcium with EGTA. Partial inhibition of both cell death and parallel production of reactive oxygen species is achieved with allopurinol, a xanthine oxidase inhibitor, leupeptin, a protease inhibitor, reducing agents such as glutathione or dithiothreitol, antioxidants such as vitamin E and vitamin C, and externally added superoxide dismutase. It is concluded that glutamate-triggered, NMDA-mediated, massive Ca2+ influx induces rapid conversion of xanthine dehydrogenase into xanthine oxidase with subsequent production of reactive oxygen species that most probably have a causal involvement in the initial steps of the series of intracellular events leading to neuronal degeneration and death. PMID:9109530

  13. Flavonoids function as antioxidants: By scavenging reactive oxygen species or by chelating iron?

    NASA Astrophysics Data System (ADS)

    Wuguo, Deng; Xingwang, Fang; Jilan, Wu

    1997-09-01

    Flavonoids have been reported to exhibit strong antioxidative activity. In the present work, a systematic mechanistic study has been performed on five flavonoids (baicalin, hesperidin, naringin, quercetin and rutin) selected according to their structural characteristics. The experimental results reveal that flavonoids function as antioxidant mainly by chelating iron ions and by scavenging peroxyl radicals whereas their OH radical scavenging effect is much less important.

  14. The nested structure of a scavenger community

    PubMed Central

    Selva, Nuria; Fortuna, Miguel A

    2007-01-01

    Scavenging is a widespread phenomenon in vertebrate communities which has rarely been accounted for, in spite of playing an essential role in food webs by enhancing nutrient recycling and community stability. Most studies on scavenger assemblages have often presented an oversimplified view of carrion foraging. Here, we applied for the first time the concept of nestedness to the study of a species-rich scavenger community in a forest ecosystem (Białowieża Primeval Forest, Poland) following a network approach. By analysing one of the most complete datasets existing up to now in a pristine environment, we have shown that the community of facultative scavengers is not randomly assembled but highly nested. A nested pattern means that species-poor carcasses support a subset of the scavenger assemblage occurring at progressively species-rich carcasses. This result contradicts the conventional view of facultative scavenging as random and opportunistic and supports recent findings in scavenging ecology. It also suggests that factors other than competition play a major role in determining community structure. Nested patterns in scavenger communities appear to be promoted by the high diversity in carrion resources and consumers, the differential predictability of the ungulate carcass types and stressful environmental conditions. PMID:17301021

  15. Inhibitory activities of soluble and bound millet seed phenolics on free radicals and reactive oxygen species.

    PubMed

    Chandrasekara, Anoma; Shahidi, Fereidoon

    2011-01-12

    Oxidative stress, caused by reactive oxygen species (ROS), is responsible for modulating several pathological conditions and aging. Soluble and bound phenolic extracts of commonly consumed millets, namely, kodo, finger (Ravi), finger (local), foxtail, proso, little, and pearl, were investigated for their phenolic content and inhibition of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and ROS, namely, hydroxyl radical, peroxyl radical, hydrogen peroxide (H(2)O(2)), hypochlorous acid (HOCl), and singlet oxygen ((1)O(2)). Inhibition of DPPH and hydroxyl radicals was detrmined using electron paramagnetic resonance (EPR) spectroscopy. The peroxyl radical inhibitory activity was measured using the oxygen radical absorbance capacity (ORAC) assay. The scavenging of H(2)O(2), HOCl, and (1)O(2) was evaluated using colorimetric methods. The results were expressed as micromoles of ferulic acid equivalents (FAE) per gram of grain on a dry weight basis. In addition, major hydroxycinnamic acids were identified and quantified using high-performance liquid chromatography (HPLC) and HPLC-mass spectrometry (MS). All millet varieties displayed effective radical and ROS inhibition activities, which generally positively correlated with phenolic contents, except for hydroxyl radical. HPLC analysis revealed the presence of ferulic and p-coumaric acids as major hydroxycinnamic acids in phenolic extract and responsible for the observed effects. Bound extracts of millet contributed 38-99% to ROS scavenging, depending on the variety and the test system employed. Hence, bound phenolics must be included in the evaluation of the antioxidant activity of millets and other cereals. PMID:21133411

  16. Standardizing Scavenger Receptor Nomenclature

    PubMed Central

    PrabhuDas, Mercy; Bowdish, Dawn; Drickamer, Kurt; Febbraio, Maria; Herz, Joachim; Kobzik, Lester; Krieger, Monty; Loike, John; Means, Terry K.; Moestrup, Soren K.; Post, Steven; Sawamura, Tatsuya; Silverstein, Samuel; Wang, Xiang-Yang; El Khoury, Joseph

    2014-01-01

    Scavenger receptors constitute a large family of proteins that are structurally diverse and participate in a wide range of biological functions. These receptors are expressed predominantly by myeloid cells and recognize a variety of ligands, including endogenous and modified host-derived molecules and microbial pathogens. There are currently eight classes of scavenger receptors, many of which have multiple names, leading to inconsistencies and confusion in the literature. To address this problem, a workshop was organized by the U.S. National Institute of Allergy and Infectious Diseases, National Institutes of Health to help develop a clear definition of scavenger receptors and a standardized nomenclature based on that definition. Fifteen experts in the scavenger receptor field attended the workshop and, after extensive discussion, reached a consensus regarding the definition of scavenger receptors and a proposed scavenger receptor nomenclature. Scavenger receptors were defined as cell surface receptors that typically bind multiple ligands and promote the removal of non-self or altered-self targets. They often function by mechanisms that include endocytosis, phagocytosis, adhesion, and signaling that ultimately lead to the elimination of degraded or harmful substances. Based on this definition, nomenclature and classification of these receptors into 10 classes were proposed. The discussion and nomenclature recommendations described in this report only refer to mammalian scavenger receptors. The purpose of this article is to describe the proposed mammalian nomenclature and classification developed at the workshop and to solicit additional feedback from the broader research community. PMID:24563502

  17. Botanical Scavenger Hunt

    ERIC Educational Resources Information Center

    Walker-Livingston, Wendy

    2009-01-01

    Why not combine the use of technology with the excitement of a scavenger hunt that moves middle-level students out into the "wilds" of their school campus to classify plants? In the lesson plan described here, students embark on a botanical scavenger hunt and then document their findings using a digital camera. This project was designed to allow…

  18. REACTOR FUEL SCAVENGING MEANS

    DOEpatents

    Coffinberry, A.S.

    1962-04-10

    A process for removing fission products from reactor liquid fuel without interfering with the reactor's normal operation or causing a significant change in its fuel composition is described. The process consists of mixing a liquid scavenger alloy composed of about 44 at.% plutoniunm, 33 at.% lanthanum, and 23 at.% nickel or cobalt with a plutonium alloy reactor fuel containing about 3 at.% lanthanum; removing a portion of the fuel and scavenger alloy from the reactor core and replacing it with an equal amount of the fresh scavenger alloy; transferring the portion to a quiescent zone where the scavenger and the plutonium fuel form two distinct liquid layers with the fission products being dissolved in the lanthanum-rich scavenger layer; and the clean plutonium-rich fuel layer being returned to the reactor core. (AEC)

  19. Oxygen radicals and renal diseases.

    PubMed

    Klahr, S

    1997-01-01

    Reactive oxygen metabolites (superoxide, hydrogen peroxide, hydroxyl radical, and hypochlorous acid) are important mediators of renal damage in acute renal failure and glomerular and tubulointerstitial diseases. The role of these oxygen metabolites in the above entities is discussed, and the effects of antioxidants and scavengers of O2 radicals are considered. The role of oxygen radicals in the regulation of gene transcription is also considered. PMID:9387104

  20. Feasibility of planned mini-laparotomy and adhesiolysis at the time of robotic-assisted radical prostatectomy in patients with prior major abdominal surgery

    PubMed Central

    Rajih, Emad; Alhathal, Naif; Alenizi, Abdullah M.; El-Hakim, Assaad

    2016-01-01

    Introduction: Our aim was to report our experience on the feasibility of completing radical prostatectomy robotically after planned open adhesiolysis for prior major abdominal surgery with previous midline laparotomy scar. Methods: We searched our prospectively collected database of robotic assisted-radical prostatectomy (RARP) performed between October 2006 and October 2012 by a single fellowship-trained surgeon to identify all patients who underwent planned initial mini-laparotomy for release of abdominal adhesions at time of RARP. Among 250 RARP patients, five patients fulfilled these criteria. Results: All patients had prostatectomy completed robotically. The mean values of patients’ demographics were as follows: Age 61.8 years (range 54–69), body mass index 30.7 (range 24.3–45.3), and prostate volume 41.5 ml (range 30.8–54). Mean operative time was 245 min (range 190–280) and estimated blood loss 410 ml (range 300–650). Median hospital stay was one day (range 1–7). Postoperatively, there was one prolonged ileus, which resolved spontaneously, and one myocardial infarction. Conclusions: Robotic completion of radical prostatectomy after open adhesiolysis is feasible. This approach maintains most minimally invasive advantages of RARP, despite a slightly longer hospital stay. In the best interest of patients, robotic surgeons are encouraged to finish the case robotically rather than attempting an open approach. PMID:27330582

  1. Breaking the dogma: PCB-derived semiquinone free radicals do not form covalent adducts with DNA, GSH, and amino acids.

    PubMed

    Wangpradit, Orarat; Rahaman, Asif; Mariappan, S V Santhana; Buettner, Garry R; Robertson, Larry W; Luthe, Gregor

    2016-02-01

    Covalent bond formations of free radical metabolites with biomolecules like DNA and proteins are thought to constitute a major mechanism of toxicity and carcinogenesis. Glutathione (GSH) is generally accepted as a radical scavenger protecting the cell. In the present study, we investigated a semiquinone radical (SQ(●-)) metabolite of the semivolatile 4-chlorobiphenyl, using electron paramagnetic resonance spectroscopy, and oxygen consumption. Proton nuclear magnetic resonance ((1)H NMR) and liquid chromatography-mass spectrometry (LC-MS) were also employed to elucidate the radical interaction with DNA, amino acids, and GSH. We found that DNA and oligonucleotides stabilized SQ(●-) by electron delocalization in the π-stacking system, resulting in persistent radical intercalated, rather than forming a covalent bond with SQ(●-). This finding was strongly supported by the semiempirical calculation of the semioccupied molecular orbital and the linear combination of the atomic orbitals, indicating 9.8 kcal mol(-1) energy gain. The insertion of SQ(●-) into the DNA strand may result in DNA strand breaks and interruption of DNA replication process or even activate radical mediated secondary reactions. The presence of amino acids resulted in a decrease of the electron paramagnetic resonance (EPR) signal of SQ(●-) and correlated with their isoelectric points. The pH shifts the equilibrium of the dianions of hydroquinone and influenced indirectly the formation of SQ(●-). Similar findings were observed with GSH and Cys. GSH and Cys functioned as indirect radical scavengers; their activities depend on their chemical equilibria with the corresponding quinones, and their further reaction via Michael addition. The generally accepted role of GSH as radical scavenger in biological systems should be reconsidered based upon these findings, questioning the generally accepted view of radical interaction of semiquinones with biologically active compounds, like DNA, amino acids

  2. Long-lived mutagenic radicals induced in mammalian cells by ionizing radiation are mainly localized to proteins.

    PubMed

    Kumagai, Jun; Masui, Kiyonao; Itagaki, Yoshiteru; Shiotani, Masaru; Kodama, Seiji; Watanabe, Masami; Miyazaki, Tetsuo

    2003-07-01

    We have provided evidence that long-lived radicals, produced by ionizing radiation, are highly mutagenic and transforming in mammalian cells. Long-lived radicals are scavenged effectively by vitamin C or by epigallocatechin-3-O-gallate (EGCG). Long-lived radicals are not involved in lethality or in the induction of chromosome aberrations. We now report the results of experiments that define the relative amounts of long-lived radicals in DNA and proteins and identify the major protein radicals as sulfinyl radicals (R-CH2-S-O*). To make these assignments, yields of long-lived radicals in gamma-irradiated salmon sperm DNA and albumin were compared by ESR. ESR spectra of long-lived radicals produced in irradiated Syrian hamster embryo (SHE) cells were analyzed precisely and compared with ESR parameters obtained by density functional theory calculations. Long-lived radicals yields of 99.8% were produced in proteins. We also identified a new type of long-lived radical as H-added phenylalanine radicals. While our evidence does not rule out the possibility of important biological consequences of the low-level long-lived radicals created by radiation, it implicates radicals in proteins as playing a key role in genetic effects of ionizing radiation. We suggest that these novel radicals, wherever they reside, need to be considered in explanations of biological sequela of radiation. PMID:12816528

  3. Peroxynitrite scavenging activity of herb extracts.

    PubMed

    Choi, Hye Rhi; Choi, Jae Sue; Han, Yong Nam; Bae, Song Ja; Chung, Hae Young

    2002-06-01

    Peroxynitrite (ONOO(-)) is a cytotoxicant with strong oxidizing properties toward various cellular constituents, including sulphydryls, lipids, amino acids and nucleotides and can cause cell death, lipid peroxidation, carcinogenesis and aging. The aim of this study was to characterize ONOO(-) scavenging constituents from herbs. Twenty-eight herbs were screened for their ONOO(-) scavenging activities with the use of a fluorometric method. The potency of scavenging activity following the addition of authentic ONOO(-) was in the following order: witch hazel bark > rosemary > jasmine tea > sage > slippery elm > black walnut leaf > Queen Anne's lace > Linden flower. The extracts exhibited dose-dependent ONOO(-) scavenging activities. We found that witch hazel (Hamamelis virginiana L.) bark showed the strongest effect for scavenging ONOO(-) of the 28 herbs. Hamamelitannin, the major active component of witch hazel bark, was shown to have a strong ability to scavenge ONOO(-). It is suggested that hamamelitannin might be developed as an effective peroxynitrite scavenger for the prevention of ONOO(-) involved diseases. PMID:12112294

  4. Antioxidant activity of olive phenols and other dietary phenols in model gastric conditions: Scavenging of the free radical DPPH and inhibition of the haem-induced peroxidation of linoleic acid.

    PubMed

    Achat, Sabiha; Rakotomanomana, Njara; Madani, Khodir; Dangles, Olivier

    2016-12-15

    The antioxidant activity of dietary phenols in humans (direct reduction of radicals and other highly oxidizing species) could be largely restricted to fighting postprandial oxidative stress in the gastric compartment. Hence, the development of chemical tests simply modelling this situation is pertinent. In this work, the antioxidant properties of the olive phenols hydroxytyrosol and oleuropein are investigated in pH 5-6 micellar solutions through the reduction of the DPPH radical and the inhibition of the metmyoglobin-induced peroxidation of linoleic acid. In the first test, hydroxytyrosol and oleuropein proved as efficient as common polyphenols and their reactivity was only moderately affected by β-cyclodextrin and bovine serum albumin, taken as models of food macromolecules. In the second test, hydroxytyrosol and oleuropein by themselves came up as relatively weak inhibitors, despite their efficiency at reducing hypervalent haem iron. However, hydroxytyrosol was able to act in synergy with the typical chain-breaking antioxidant α-tocopherol. PMID:27451164

  5. Novel estrogens and their radical scavenging effects, iron-chelating, and total antioxidative activities: 17 alpha-substituted analogs of delta 9(11)-dehydro-17 beta-estradiol.

    PubMed

    Römer, W; Oettel, M; Menzenbach, B; Droescher, P; Schwarz, S

    1997-11-01

    Antioxidant effects of N,N-dimethyl-p-toluidine, p-cresol, and p-(hydroxy)thioanisol 17 alpha-substituted analogs of 17 beta-estradiol and their delta 9(11)-dehydro homologs were investigated using four different in vitro models: rat synaptosomal lipid peroxidation induced by Fenton's reagent, Fe(II)-chelating activities, the formation of superoxide anion radicals, and total antioxidative activity. Whereas the classical estrogen 17 beta-estradiol as well as selected phenolic compounds was only moderately inhibiting iron-dependent lipid peroxidation and stimulating total antioxidative activity, besides delta 9(11)-dehydro-17 beta-estradiol (J 1213), novel estrogens such as C-17-oriented side chain analogs of 17 beta-estradiol (J 843, J 872, and J 897) and delta 9(11)-dehydro homologs (J 844, J 864, and J 898) directly altered the iron redox chemistry and diminished the formation of superoxide anion radicals generated by a xanthine/xanthine oxidase-dependent luminescence reaction to a great extent. These results suggest that definite modifications in the chemical structure of 17 beta-estradiol, e.g., the introduction of a delta 9(11)-double bond and/or p-cresol as well as p-(hydroxy)thioanisol C-17 substitution, may result in substantial changes in their antioxidant behavior. These compounds may be drug candidates for treating pathologies related to free radical formation. PMID:9366006

  6. Cooperative effects of scavengers on the scavenged yield of the hydrated electron

    SciTech Connect

    Pimblott, S.M.; LaVerne, J.A.

    1992-10-29

    An analytic description of the cooperative effects of scavengers on the radiation chemistry of the hydrated electron in aqueous solution is developed by using the available experimental data and the results of deterministic diffusion-kinetic calculations. The formulation has two components: the first corresponds to the effect of the primary (electron) scavenger in isolation and the second represents the suppression of the e{sub aq}{sup {minus}} + OH spur reaction by the secondary (hydroxyl radical) scavenger. The two aqueous systems that have been considered in detail are nitrate/formate and nitrous oxide/2-propanol. The agreement between the analytic treatment, the experimental data, and the kinetic modeling is good. 37 refs., 7 figs., 2 tabs.

  7. A Geometric Scavenger Hunt

    ERIC Educational Resources Information Center

    Smart, Julie; Marshall, Jeff

    2007-01-01

    Children possess a genuine curiosity for exploring the natural world around them. One third grade teacher capitalized on this inherent trait by leading her students on "A Geometric Scavenger Hunt." The four-lesson inquiry investigation described in this article integrates mathematics and science. Among the students' discoveries was the fact that…

  8. A Geospatial Scavenger Hunt

    ERIC Educational Resources Information Center

    Martinez, Adriana E.; Williams, Nikki A.; Metoyer, Sandra K.; Morris, Jennifer N.; Berhane, Stephen A.

    2009-01-01

    With the use of technology such as Global Positioning System (GPS) units and Google Earth for a simple-machine scavenger hunt, you will transform a standard identification activity into an exciting learning experience that motivates students, incorporates practical skills in technology, and enhances students' spatial-thinking skills. In the…

  9. A novel sulfite alternative scavenger and benefits for the use of traced oxygen scavengers

    SciTech Connect

    Batton, C.B.; Riede, R.F.

    1994-12-31

    Dissolved oxygen in boiler systems is known to cause corrosion. Mechanical deaeration removes the majority of the dissolved oxygen while oxygen scavengers remove the remaining trace level. Sodium sulfate is a commonly used scavenger, but has several use limitations, such as high solids contribution to boiler water and decomposition products that are corrosive gases which can cause downstream equipment problems. A novel sulfite replacement oxygen scavenger has been developed which addresses the limitations of sulfite. Identification and demonstrated performance of the new scavenger is presented using both research and field data. In addition to oxygen scavenger performance, the success of a boiler water treatment program is dependent upon the correct dosage added to the feedwater. Plant managers and operators often struggle with indirect or inaccurate methods to determine what is occurring within their system. An oxygen scavenger product containing a proprietary fluorescent tracer has been developed. This technology for boilers provides a breakthrough in measurement capability for monitoring the dynamics of a boiler system. These two oxygen scavenger developments represent the result of maintaining desirable performance characteristics and significantly improving current technology. Laboratory and field data supporting these results are presented.

  10. Scavenging of reactive oxygen species by silibinin dihemisuccinate.

    PubMed

    Mira, L; Silva, M; Manso, C F

    1994-08-17

    Silibinin dihemisuccinate (SDH) is a flavonoid of plant origin with hepatoprotective effects which have been partially attributed to its ability to scavenge oxygen free radicals. In the present paper the antioxidant properties of SDH were evaluated by studying the ability of this drug to react with relevant biological oxidants such as superoxide anion radical (O2-), hydrogen peroxide (H2O2), hydroxyl radical (HO.) and hypochlorous acid (HOCl). In addition, its effect on lipid peroxidation was investigated. SDH is not a good scavenger of O2- and no reaction with H2O2 was detected within the sensitivity limit of our assay. However, it reacts rapidly with HO. radicals in free solution at approximately diffusion-controlled rate (K = (1.0-1.2) x 10(10)/M/sec) and appears to be a weak iron ion chelator. SDH at concentrations in the micromolar range protected alpha 1-antiproteinase against inactivation by HOCl, showing that it is a potent scavenger of this oxidizing species. Luminol-dependent chemiluminescence induced by HOCl was also inhibited by SDH. The reaction of SDH with HOCl was monitored by the modification of the UV-visible spectrum of SDH. The studies on rat liver microsome lipid peroxidation induced by Fe(III)/ascorbate showed that SDH has an inhibitory effect, which is dependent on its concentration and the magnitude of lipid peroxidation. This work supports the reactive oxygen species scavenger action ascribed to SDH. PMID:8080448

  11. [Possible significance of free oxygen radicals for reperfusion injury].

    PubMed

    Becker, B F; Massoudy, P; Permanetter, B; Raschke, P; Zahler, S

    1993-01-01

    Enhanced formation of radicals during post-ischemic reperfusion, foremost of superoxide (O2-) and hydroxyl (OH) radicals, has been directly and indirectly demonstrated in a number of tissues. However, the close chemical interrelationship of O2- and OH with other non-radical oxidants, such as hydrogen peroxide (H2O2) and hypochlorous acid (HOCl), makes it prudent to speak of reactive oxygen metabolites in conjunction with cell and organ dysfunction incurred by reperfusion. In the case of the heart, evidence for the causal involvement of such reactive molecular species includes (1) the increased formation of lipid peroxides, (2) the ability to mimic all facets of reperfusion injury (arrhythmias, contractile and vascular dysfunction, infarct extension) by exogenously applying reactive oxygen species, and (3) the propensity of a great variety of antioxidative and radical scavenging measures to afford cardioprotection during reperfusion. Potential sources of reactive oxygen metabolites in the reperfused heart are the mitochondrial redox-chain, endothelial enzymes such as cyclooxygenase, monoaminooxidase, NO-synthase and xanthine oxidase, and formed blood constituents (platelets, monocytes, granulocytes). According to our own results, adenosine, endogenously formed in the heart during ischemia, rapidly enhances adhesion of granulocytes introduced into the coronary system at reperfusion. Furthermore, small numbers of these cells suffice to induce contractile dysfunction in an isolated guinea pig heart model of ischemia-reperfusion injury, the major mediator of damage being HOCl. The striking disparity between the enormous volume of experimental data supporting involvement of reactive oxygen metabolites in reperfusion damage and the virtual lack of clinical-therapeutic regimens employing anti-oxidative measures is largely due to a still rudimentary knowledge of the homeostatic control of formation and removal of radicals and oxidants. In particular, the inability to

  12. Radiolytic generation of radical cations in xenon matrices. Tetramethylcyclopropane radical cation and its transformations

    SciTech Connect

    Qin, X.Z.; Trifunac, A.D. )

    1990-04-05

    Radiolytic generation of radical cations in xenon matrices containing electron scavengers is illustrated by studying the 1,1,2,2-tetramethylcyclopropane radical cation. Dilute and concentrated solutions of tetramethylcyclopropane in xenon without electron scavengers and neat tetramethylcyclopropane yielded neutral radicals upon {gamma}-irradiation. Speculation on the mechanisms of radical formation is presented. The radical species observed in the {gamma}-irradiation of neat tetramethylcyclopropane appears to be identical with the paramagnetic species observed in CF{sub 2}ClCFCl{sub 2} above 120 K, suggesting that a neutral radical rather than the ring-opened distonic radical cation is observed in the CF{sub 2}ClCFCl{sub 2} matrix.

  13. Cryogenic Propellant Scavenging

    NASA Technical Reports Server (NTRS)

    Louie, B.; Kemp, N. J.; Daney, D. E.

    1985-01-01

    A detailed description of a computer model that has been developed for assessing the feasibility of low g cryogen propellant scavenging from the space shuttle External Tank (ET) is given. Either pump-assisted or pressure-induced propellant transfer may be selected. The program will accept a wide range of input variables, including the fuel to be transferred (LOX or LH2), heat leaks, tank temperatures, and piping and equipment specifications. The model has been parametrically analyzed to determine initial design specification for the system.

  14. Reassessing Radical Pedagogy.

    ERIC Educational Resources Information Center

    Sweet, Stephen

    1998-01-01

    Responds to comments about, and critiques of, his own article on radical pedagogy. Outlines major points of contention raised by other commentators and responds to them, including matters of definition, power relations in the classroom, and tempering radical theory with pragmatism. (DSK)

  15. Atmospheric scavenging exhaust

    NASA Technical Reports Server (NTRS)

    Fenton, D. L.; Purcell, R. Y.

    1977-01-01

    Solid propellant rocket exhaust was directly utilized to ascertain raindrop scavenging rates for hydrogen chloride. The airborne HCl concentration varied from 0.2 to 10.0 ppm and the raindrop sizes tested included 0.55 mm, 1.1 mm, and 3.0 mm. Two chambers were used to conduct the experiments. A large, rigid walled, spherical chamber stored the exhaust constituents while the smaller chamber housing all the experiments was charged as required with rocket exhaust HCl. Surface uptake experiments demonstrated an HCl concentration dependence for distilled water. Sea water and brackish water HCl uptake was below the detection limit of the chlorine-ion analysis technique employed. Plant life HCl uptake experiments were limited to corn and soybeans. Plant age effectively correlated the HCl uptake data. Metallic corrosion was not significant for single 20 minute exposures to the exhaust HCl under varying relative humidity.

  16. Contemporary Radical Prostatectomy

    PubMed Central

    Fu, Qiang; Moul, Judd W.; Sun, Leon

    2011-01-01

    Purpose. Patients diagnosed with clinically localized prostate cancer have more surgical treatment options than in the past. This paper focuses on the procedures' oncological or functional outcomes and perioperative morbidities of radical retropubic prostatectomy, radical perineal prostatectomy, and robotic-assisted laparoscopic radical prostatectomy. Materials and Methods. A MEDLINE/PubMed search of the literature on radical prostatectomy and other new management options was performed. Results. Compared to the open procedures, robotic-assisted radical prostatectomy has no confirmed significant difference in most literatures besides less blood loss and blood transfusion. Nerve sparing is a safe means of preserving potency on well-selected patients undergoing radical prostatectomy. Positive surgical margin rates of radical prostatectomy affect the recurrence and survival of prostate cancer. The urinary and sexual function outcomes have been vastly improved. Neoadjuvant treatment only affects the rate of positive surgical margin. Adjuvant therapy can delay and reduce the risk of recurrence and improve the survival of the high risk prostate cancer. Conclusions. For the majority of patients with organ-confined prostate cancer, radical prostatectomy remains a most effective approach. Radical perineal prostatectomy remains a viable approach for patients with morbid obesity, prior pelvic surgery, or prior pelvic radiation. Robot-assisted laparoscopic prostatectomy (RALP) has become popular among surgeons but has not yet become the firmly established standard of care. Long-term data have confirmed the efficacy of radical retropubic prostatectomy with disease control rates and cancer-specific survival rates. PMID:22110994

  17. Demonstration of free radical generation in the "stunned" myocardium in the conscious dog and identification of major differences between conscious and open-chest dogs.

    PubMed Central

    Li, X Y; McCay, P B; Zughaib, M; Jeroudi, M O; Triana, J F; Bolli, R

    1993-01-01

    Conscious dogs undergoing a 15-min coronary occlusion were given alpha-phenyl N-tert-butyl nitrone (PBN) and the local coronary venous plasma was analyzed by electron paramagnetic resonance spectroscopy. A prolonged myocardial release of PBN radical adducts was observed, which exhibited a burst in the initial minutes of reflow (peaking at 3 min) and then abated but continued for 1-3 h after reperfusion. Computer simulation revealed the presence of at least two PBN adducts (aN = 15.2 G and a beta H = 6.0 G; aN = 14.6 G and a beta H = 3.0 G), both consistent with the trapping of secondary carbon-centered radicals. No appreciable PBN adduct production was observed when collateral flow exceeded 30-40% of nonischemic flow, indicating that a flow reduction of at least 60% is necessary to trigger free radical reactions. There was a direct relationship between the magnitude of PBN adduct production and the severity of contractile dysfunction (r = 0.77), suggesting that the radicals generated upon reperfusion play a causal role in the subsequent stunning. The total release of PBN adducts after 3 h of reperfusion following a 15-min coronary occlusion was found to be approximately five times greater in open-chest compared with conscious dogs; at the same time, the recovery of wall thickening was markedly less in open-chest dogs. This study represents the first application of spin trapping to a conscious animal model of myocardial ischemia. The results demonstrate (a) that free radicals are generated in the stunned myocardium in the absence of the artificial or abnormal conditions associated with previously used models (isolated hearts, open-chest preparations), and (b) that both the severity of postischemic dysfunction and the magnitude of the attendant free radical production are greatly exaggerated in the open-chest dog, implying that previous conclusions derived from this model may not be applicable to conscious animals or to humans. This investigation also provides a

  18. A new polyphenolics with strong radical scavenging activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oxidative stress and antioxidant are believed to be involved in aging process. Dietary antioxidant may delay the onset of aging and progression of chronic disease associated with aging. Herbal medicines are still the mainstay of about 75–80 percent of the world population. We have identified and iso...

  19. Use of countercurrent chromatography during isolation of 6-hydroxyluteolin-7-O-β-glucoside, a major antioxidant of Athrixia phylicoides.

    PubMed

    de Beer, Dalene; Joubert, Elizabeth; Malherbe, Christiaan J; Jacobus Brand, D

    2011-09-01

    Athrixia phylicoides, an indigenous South African herbal tea, has potential as a source of nutraceutical antioxidant extracts. Countercurrent chromatography (CCC) was employed as part of a multi-step process to isolate one of the major antioxidant compounds in A. phylicoides extracts. Antioxidant activity of the extracts was comparable to commercial nutraceutical extracts from Aspalathus linearis and Cyclopia spp. in a range of assays. The extracts were tested for radical scavenging (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) di-ammonium radical cation (ABTS·⁺) scavenging, 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging and oxygen radical absorbance capacity (ORAC)), ferric reducing antioxidant potential (FRAP) and iron chelating activity, as well as inhibition of microsomal lipid and linoleic acid emulsion oxidation. After extraction optimisation, the antioxidant activity of the major phenolic compounds in an A. phylicoides extract was determined using the on-line HPLC-diode-array-DPPH and -ABTS·⁺ radical scavenging assays. Major compounds reported for the first time included chlorogenic acid, 1,3-dicaffeoylquinic acid, several hydroxycinnamic acid derivatives, including dicaffeoyl quinic acids, and an unidentified flavone-hexose. Finally, CCC was used in conjunction with liquid-liquid partitioning and semi-preparative reversed-phase HPLC to isolate 6-hydroxyluteolin-7-O-β-glucoside (a major antioxidant) and quercetagetin-7-O-β-glucoside (a minor compound present in CCC fraction containing 6-hydroxyluteolin-7-O-β-glucoside) from an A. phylicoides extract. The chemical structures of the isolated compounds were confirmed by LC high-resolution electrospray ionisation MS, as well as ¹H, ¹³C and 2D NMR spectroscopy. This is the first report of the isolation of these compounds from A. phylicoides. PMID:21236437

  20. Scavenging for Better Library Instruction.

    ERIC Educational Resources Information Center

    Cocking, Terry S.; Schafer, Susan A.

    1994-01-01

    Describes the Library Scavenger Hunt program at Baylor University (part of the reading and study skills program) which emphasizes learning what sources are available in a college library, where they are located, and how to use them. (SR)

  1. Scavenger Receptors: Emerging Roles in Cancer Biology and Immunology

    PubMed Central

    Yu, Xiaofei; Guo, Chunqing; Fisher, Paul B.; Subjeck, John R.; Wang, Xiang-Yang

    2015-01-01

    Scavenger receptors constitute a large family of evolutionally conserved protein molecules that are structurally and functionally diverse. Although scavenger receptors were originally identified based on their capacity to scavenge modified lipoproteins, these molecules have been shown to recognize and bind to a broad spectrum of ligands, including modified and unmodified host-derived molecules or microbial components. As a major subset of innate pattern recognition receptors, scavenger receptors are mainly expressed on myeloid cells and function in a wide range of biological processes, such as endocytosis, adhesion, lipid transport, antigen presentation, and pathogen clearance. In addition to playing a crucial role in maintenance of host homeostasis, scavenger receptors have been implicated in the pathogenesis of a number of diseases, e.g., atherosclerosis, neurodegeneration, or metabolic disorders. Emerging evidence has begun to reveal these receptor molecules as important regulators of tumor behavior and host immune responses to cancer. This review summarizes our current understanding on the newly identified, distinct functions of scavenger receptors in cancer biology and immunology. The potential of scavenger receptors as diagnostic biomarkers and novel targets for therapeutic interventions to treat malignancies is also highlighted. PMID:26216637

  2. Free radical reactions and antioxidant activities of sesamol: pulse radiolytic and biochemical studies.

    PubMed

    Joshi, Ravi; Kumar, M Sudheer; Satyamoorthy, K; Unnikrisnan, M K; Mukherjee, Tulsi

    2005-04-01

    Sesamol (from Sesamum indicum) is a dietary compound, which is soluble in aqueous as well as lipid phases. Free radical scavenging reactions of sesamol, 5-hydroxy-1,3-benzodioxole, have been studied using a nanosecond pulse radiolysis technique. Sesamol efficiently scavenges hydroxyl, one-electron oxidizing, organo-haloperoxyl, lipid peroxyl, and tryptophanyl radicals. Its antioxidant activity has also been evaluated with cyclic voltammetry. In biochemical studies, it has been found to inhibit lipid peroxidation, hydroxyl radical-induced deoxyribose degradation, and DNA cleavage. These antioxidant and free radical scavenging activities of sesamol have been reported in the paper. PMID:15796613

  3. Inactivation efficiencies of radical reactions with biologically active DNA

    NASA Astrophysics Data System (ADS)

    Lafleur, M. V. M.; Retèl, J.; Loman, H.

    Dilute aqueous solutions of biologically active θX174 DNA may serve as a simplified model system of the cell. Damage to the DNA after irradiation with γ-rays, may be ascribed to reactions with .OH, .H and e -aq or secondary radicals, arising from reactions of water radicals with added scavengers. Conversion of primary (water) radicals into secondary (scavenger) radicals leads to a considerable protection of the DNA, which, however, would have been larger if these secondary radicals did not contribute to DNA inactivation. The inactivation yield due to isopropanol or formate (secondary) radicals depends on dose rate as well as DNA concentration. Furthermore the inactivation efficiencies of the reactions of both the primary and the secondary radicals with single-stranded DNA could be established.

  4. Antioxidant Activity of Extract and Its Major Constituents from Okra Seed on Rat Hepatocytes Injured by Carbon Tetrachloride

    PubMed Central

    Hu, Lianmei; Yu, Wenlan; Li, Ying; Tang, Zhaoxin

    2014-01-01

    The antioxidant activities and protective effects of total phenolic extracts (TPE) and their major components from okra seeds on oxidative stress induced by carbon tetrachloride (CCl4) in rat hepatocyte cell line were investigated. The major phenolic compounds were identified as quercetin 3-O-glucosyl (1 → 6) glucoside (QDG) and quercetin 3-O-glucoside (QG). TPE, QG, and QDG from okra seeds exhibited excellent reducing power and free radical scavenging capabilities including α, α-diphenyl-β-picrylhydrazyl (DPPH), superoxide anions, and hydroxyl radical. Overall, DPPH radical scavenging activity and reducing power of QG and QDG were higher than those of TPE while superoxide and hydroxyl radical scavenging activities of QG and TPE were higher than those of QDG. Furthermore, TPE, QG, and QDG pretreatments significantly alleviated the cytotoxicity of CCl4 on rat hepatocytes, with attenuated lipid peroxidation, increased SOD and CAT activities, and decreased GPT and GOT activities. The protective effects of TPE and QG on rat hepatocytes were stronger than those of QDG. However, the cytotoxicity of CCl4 on rat hepatocytes was not affected by TPE, QG, and QDG posttreatments. It was suggested that the protective effects of TPE, QG, and QDG on rat hepatocyte against oxidative stress were related to the direct antioxidant capabilities and the induced antioxidant enzymes activities. PMID:24719856

  5. Antioxidant activity of extract and its major constituents from okra seed on rat hepatocytes injured by carbon tetrachloride.

    PubMed

    Hu, Lianmei; Yu, Wenlan; Li, Ying; Prasad, Nagendra; Tang, Zhaoxin

    2014-01-01

    The antioxidant activities and protective effects of total phenolic extracts (TPE) and their major components from okra seeds on oxidative stress induced by carbon tetrachloride (CCl4) in rat hepatocyte cell line were investigated. The major phenolic compounds were identified as quercetin 3-O-glucosyl (1 → 6) glucoside (QDG) and quercetin 3-O-glucoside (QG). TPE, QG, and QDG from okra seeds exhibited excellent reducing power and free radical scavenging capabilities including α, α-diphenyl-β-picrylhydrazyl (DPPH), superoxide anions, and hydroxyl radical. Overall, DPPH radical scavenging activity and reducing power of QG and QDG were higher than those of TPE while superoxide and hydroxyl radical scavenging activities of QG and TPE were higher than those of QDG. Furthermore, TPE, QG, and QDG pretreatments significantly alleviated the cytotoxicity of CCl4 on rat hepatocytes, with attenuated lipid peroxidation, increased SOD and CAT activities, and decreased GPT and GOT activities. The protective effects of TPE and QG on rat hepatocytes were stronger than those of QDG. However, the cytotoxicity of CCl4 on rat hepatocytes was not affected by TPE, QG, and QDG posttreatments. It was suggested that the protective effects of TPE, QG, and QDG on rat hepatocyte against oxidative stress were related to the direct antioxidant capabilities and the induced antioxidant enzymes activities. PMID:24719856

  6. Analysis and functionality of major polyphenolic components of Polygonum cuspidatum (itadori).

    PubMed

    Kirino, Akiko; Takasuka, Yuka; Nishi, Asami; Kawabe, Satoko; Yamashita, Hiromi; Kimoto, Masumi; Ito, Hideyuki; Tsuji, Hideaki

    2012-01-01

    Polygonum cuspidatum has been broadly utilized as a herbal medicine in Asia, but the outline of the polyphenol compounds in the plant has not been characterized well. In the present study, the major polyphenolic components were isolated from the roots of P. cuspidatum, and identified as resveratrol and its glucosides, resveratroloside and polydatin. On the other hand, chlorogenic acid was found to be one of the polyphenolic components in the leaves and stems of the plant. Next, we elucidated that resveratrol derivatives and chlorogenic acid exhibit α-glucosidase inhibitory activities, and resveratroloside exhibits the same inhibitory activity as quercetin does. Furthermore, DPPH radical scavenging activities of antioxidants including resveratrol derivatives and chlorogenic acid derivatives were examined by initial rate analyses of their reactions. Subsequently, it was revealed that resveratrol derivatives have slow-acting effects on the radical scavenging activity and that chlorogenic acid derivatives exhibit very fast-acting effects. PMID:23132312

  7. Traditional reactive carbonyl scavengers do not prevent the carbonylation of brain proteins induced by acute glutathione depletion.

    PubMed

    Zheng, J; Bizzozero, O A

    2010-03-01

    This study investigated the effect of reactive carbonyl species (RCS)-trapping agents on the formation of protein carbonyls during depletion of brain glutathione (GSH). To this end, rat brain slices were incubated with the GSH-depletor diethyl maleate in the absence or presence of chemically different RCS scavengers (hydralazine, methoxylamine, aminoguanidine, pyridoxamine, carnosine, taurine and z-histidine hydrazide). Despite their strong reactivity towards the most common RCS, none of the scavengers tested, with the exception of hydralazine, prevented protein carbonylation. These findings suggest that the majority of protein-associated carbonyl groups in this oxidative stress paradigm do not derive from stable lipid peroxidation products like malondialdehyde (MDA), acrolein and 4-hydroxynonenal (4-HNE). This conclusion was confirmed by the observation that the amount of MDA-, acrolein- and 4-HNE-protein adducts does not increase upon GSH depletion. Additional studies revealed that the efficacy of hydralazine at preventing carbonylation was due to its ability to reduce oxidative stress, most likely by inhibiting mitochondrial production of superoxide and/or by scavenging lipid free radicals. PMID:20001647

  8. Determination of reactions between free radicals and selected Chilean wines and transition metals by ESR and UV-vis technique

    NASA Astrophysics Data System (ADS)

    Espinoza, Mónica; Olea-Azar, Claudio; Speisky, Hernán; Rodríguez, Jorge

    2009-01-01

    Four different types of Chilean wines (Cabernet Sauvignon, Merlot, Carmenere and Syrah) were selected and examined in their free radical scavenging capacities by electron spin resonance (ESR) and spectrophotometric methods. The free radical scavenging properties were evaluated against 2,2-diphenyl-1-picrylhydrazyl (DPPH rad ) radical, 2,6-di- tert-butyl-alpha-(3,5-di- tert-butyl-4-oxo-2,5-cyclohexadien-1-ylidene)- p-tolyloxy (Galvinoxyl) radical and hydroxyl radical (HO rad ). The possible effect on these scavenging properties of added transition metals to these wines was evaluated. Among the wines evaluated, Cabernet Sauvignon was the one with the highest activity against all radicals tested. The presence of added copper or iron to wines resulted in a reduced free radical scavenging capacity for all type of wines studied. The formation of redox inactive complexes between polyphenols of wine and transition metals is the possible cause of this reduction in antioxidant activity.

  9. Essential oil phenyl propanoids. Useful as .OH scavengers?

    PubMed

    Taira, J; Ikemoto, T; Yoneya, T; Hagi, A; Murakami, A; Makino, K

    1992-01-01

    In order to search for radical scavengers which could be used as raw materials for cosmetics, phenyl propanoids (eugenol, isoeugenol, dehydrodieugenol, dehydrodieugenol B and coniferyl aldehyde) were examined for their hydroxyl radical (.OH) scavenging ability. A Fenton system was used to produce .OH. In order to see scavenging by these phenyl propanoids, competition reactions between a spin trap, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), and these phenyl propanoids for .OH were studied. The relative yield of the spin adduct of .OH (DMPO-OH) was measured by electron spin resonance spectroscopy. The approximate rate constants of the reactions between these phenyl propanoids and .OH estimated by measuring the reduced height of the ESR signals of DMPO-OH were found to be at least in the order of 10(9) M-1 s-1 (diffusion-controlled). Also, using the TBA tests, the reactions between .OH and several compounds reactive with .OH were investigated in the presence of the phenyl propanoids and it was found that the phenyl propanoids compete with such reactive compounds for .OH. These results indicate that these phenyl propanoids can be used as antioxidants for skin damage perhaps caused by .OH generated by UV-light. PMID:1318253

  10. Identification of major phenolic compounds of Chinese water chestnut and their antioxidant activity.

    PubMed

    You, Yanli; Duan, Xuewu; Wei, Xiaoyi; Su, Xinguo; Zhao, Mouming; Sun, Jian; Ruenroengklin, Neungnapa; Jiang, Yueming

    2007-01-01

    Chinese water chestnut (CWC) is one of the most popular foods among Asian people due to its special taste and medical function. Experiments were conducted to test the antioxidant activity and then determine the major phenolic compound components present in CWC. CWC phenolic extract strongly inhibited linoleic acid oxidation and exhibited a dose-dependent free-radical scavenging activity against alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) radicals, superoxide anions and hydroxyl radicals, which was superior to ascorbic acid and butylated hydroxytoluene (BHT), two commercial used antioxidants. Furthermore, the CWC extract was found to have a relatively higher reducing power, compared with BHT. The major phenolic compounds present in CWC tissues were extracted, purified and identified by high-performance liquid chromatograph (HPLC) as (-)-gallocatechin gallate, (-)-epicatechin gallate and (+)-catechin gallate. This study suggests that CWC tissues exhibit great potential for antioxidant activity and may be useful for their nutritional and medicinal functions. PMID:17851436

  11. Radical Hysterectomy

    MedlinePlus

    ... the base of her partner’s penis during intercourse. Orgasm after radical hysterectomy Women who have had a ... the surgery will affect their ability to have orgasms. This has not been studied a great deal, ...

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

    NASA Astrophysics Data System (ADS)

    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

  13. Pyrroloquinoline-quinone: a reactive oxygen species scavenger in bacteria.

    PubMed

    Misra, Hari S; Khairnar, Nivedita P; Barik, Atanu; Indira Priyadarsini, K; Mohan, Hari; Apte, Shree K

    2004-12-01

    Transgenic Escherichia coli expressing pyrroloquinoline-quinone (PQQ) synthase gene from Deinococcus radiodurans showed superior survival during Rose Bengal induced oxidative stress. Such cells showed significantly low levels of protein carbonylation as compared to non-transgenic control. In vitro, PQQ reacted with reactive oxygen species with rate constants comparable to other well known antioxidants, producing non-reactive molecular products. PQQ also protected plasmid DNA and proteins from the oxidative damage caused by gamma-irradiation in solution. The data suggest that radioprotective/oxidative stress protective ability of PQQ in bacteria may be consequent to scavenging of reactive oxygen species per se and induction of other free radical scavenging mechanism. PMID:15581610

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

    PubMed

    Waqas, Muhammad Khurram; Saqib, Najam-Us; Rashid, Saeed-Ur; Shah, Pervaiz Akhtar; Akhtar, Naveed; Murtaza, Ghulam

    2013-01-01

    Aiming at the exploration of herbal use by society, crude extracts of the seeds of some commonly used medicinal plants (Vitis vinifera, Tamarindus indica and Glycin max) were screened for their free radical scavenging properties using ascorbic acid as standard antioxidant. Free radical scavenging activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. The overall antioxidant activity of grape seeds (Vitis vinifera) was the strongest, followed in descending order by soybean (Glycin max) and tamarind (Tamarindus indica). The seeds extract of Vitis vinifera, Glycin max and Tamarindus indica showed 85.61%, 83.45% and 79.26%, DPPH scavenging activity respectively. PMID:24311867

  15. Free radical metabolism of ethanol by deermouse microsomes

    SciTech Connect

    Knecht, K.T.; Thurman, R.G.; Mason, R.P. NIEHS, Research Triangle Park, NC )

    1991-03-15

    One-electron oxidation of ethanol to the {alpha}-hydroxyethyl radical by rat liver microsomes was previously found to be cytochrome P-450-dependent in the presence of Desferal. With deermouse microsomes, the formation of {alpha}-hydroxyethyl radical from ethanol was demonstrated with the electron paramagnetic resonance (EPR) technique of spin trapping. Free radical formation was enhanced by pretreatment of the animals with ethanol. Boiling of the microsomes, omission of NADPH, or addition of superoxide dismutase abolished free radical formation, but addition of catalase or azide had no affect. Free radicals from the hydroxyl radical scavenger formate were detected when ethanol in the incubation medium was replaced by formate. When equal concentrations of ethanol and formate were added to microsomes, the intensity of each radical adduct signal was decreased by half. Thus, it is concluded that free radical formation in deermouse microsomes is mediated by a P-450-derived, superoxide-dependent oxidizing species.

  16. Effects of electron acceptors and radical scavengers on nonchain radical nucleophilic substitution reactions

    SciTech Connect

    Xianman Zhang; Dilun Yang; Youcheng Liu )

    1993-01-01

    The yields of reaction products from thermal nucleophilic substitution reactions in dimethyl sulfoxide (DMSO) of six o- and p-nitrohalobenzenes with the sodium salt of ethyl [alpha]-cyanoacetate carbanion [Na[sup +][sup [minus

  17. Indole alkaloids from Vinca major and V. minor growing in Turkey.

    PubMed

    Bahadori, Fatemeh; Topçu, Gülaçti; Boğa, Mehmet; Türkekul, Ayla; Kolak, Ufuk; Kartal, Murat

    2012-06-01

    A new indole alkaloid, 11-hydroxypolyneuridine, was isolated from Vinca major subsp. major L. and the known indole alkaloids vallesiachotamine and isovallesiachotamine from Vinca minor L. This is the first report on the alkaloids of both Vinca species growing in Turkey; vallesiachotamine and isovallesiachotamine were isolated from a Vinca species for the first time. V. minor may be considered as a new source for these two alkaloids due to their occurrence in high amount in the aerial parts of the plant. The alkaloid extracts of the two Vinca species were found to have high lipid peroxidation inhibitory and DPPH radical scavenging activities. Anticholinesterase activity of the extracts was also very strong. PMID:22816294

  18. The free radical chemistry of cloud droplets and its impact upon the composition of rain

    NASA Technical Reports Server (NTRS)

    Chameides, W. L.; Davis, D. D.

    1982-01-01

    Calculations are presented that simulate the free radical chemistries of the gas phase and aqueous phase within a warm cloud during midday. It is demonstrated that in the presence of midday solar fluxes, the heterogeneous scavenging of OH and HO2 from the gas phase by cloud droplets can represent a major source of free radicals to cloud water, provided the accommodation or sticking coefficient for these species impinging upon water droplets is not less than 0.0001. The aqueous-phase of HO2 radicals are found to be converted to H2O2 by aqueous-phase chemical reactions at a rate that suggests that this mechanism could produce a significant fraction of the H2O2 found in cloud droplets. The rapid oxidation of sulfur species dissolved in cloudwater by this free-radical-produced H2O2 as well as by aqueous-phase OH radicals could conceivably have a significant impact upon the chemical composition of rain.

  19. [Angiotensin-converting enzyme inhibitors as neutralizers of hydroxyl radical].

    PubMed

    Mira, M L; Silva, M M; Queirós, M J; Manso, C

    1992-05-01

    Angiotensin converting enzyme inhibitors are utilized in the treatment of essential hypertension and of chronic cardiac failure. They are also employed in the treatment of the myocardial lesion of ischemia-reperfusion, which involves oxygen free radicals. In the present study we investigated the possibility of three angiotensin converting enzyme inhibitors (captopril, enalapril, lisinopril) to act as hydroxyl radical scavengers. The rate constants for reactions of those compounds with .OH were determined using the deoxyribose method. All there compounds proved to be good scavengers of .OH with rate constants of about 10(10)M-1s-1 and are iron chelators specially enalapril. The fact that captopril possesses a thiol group does not confer an higher antioxidative capacity. These results suggest that scavenging of oxygen free radicals may be a possible mechanism contributing to the therapeutic effect of angiotensin converting enzyme inhibitors. PMID:1325814

  20. Different Reactive Oxygen Species Scavenging Properties of Flavonoids Determine Their Abilities to Extend the Shelf Life of Tomato1[OPEN

    PubMed Central

    Zhang, Yang; De Stefano, Rosalba; Robine, Marie; Butelli, Eugenio; Bulling, Katharina; Hill, Lionel; Rejzek, Martin; Martin, Cathie; Schoonbeek, Henk-jan

    2015-01-01

    The shelf life of tomato (Solanum lycopersicum) fruit is determined by the processes of overripening and susceptibility to pathogens. Postharvest shelf life is one of the most important traits for commercially grown tomatoes. We compared the shelf life of tomato fruit that accumulate different flavonoids and found that delayed overripening is associated with increased total antioxidant capacity caused by the accumulation of flavonoids in the fruit. However, reduced susceptibility to Botrytis cinerea, a major postharvest fungal pathogen of tomato, is conferred by specific flavonoids only. We demonstrate an association between flavonoid structure, selective scavenging ability for different free radicals, and reduced susceptibility to B. cinerea. Our study provides mechanistic insight into how flavonoids influence the shelf life, information that could be used to improve the shelf life of tomato and, potentially, other soft fruit. PMID:26082399

  1. Scavenging 4-Oxo-2-nonenal.

    PubMed

    Amarnath, Venkataraman; Amarnath, Kalyani

    2015-10-19

    4-Oxo-2-nonenal (ONE), a product of cellular lipid oxidation, reacts nonspecifically with the lysine residues of proteins and is generated in increased amounts during degenerative diseases and cancer. We show that pyridoxamine, salicylamine, and related 2-aminomethylphenols react with ONE, to form pyrrolo[2,1-b][1,3]oxazines with the participation of both the amino and the phenolic groups. 2-Aminomethylphenols react with ONE as well as with the Michael adducts of ONE much more rapidly than lysine, suggesting their use for therapeutically scavenging ONE. PMID:2635556