Lipid peroxidation and ascorbic acid levels in Nigeria children with ...

African Journals Online (AJOL)

This study was undertaken to establish data on the roles of lipid peroxidation and ascorbic acid in the pathology of malaria in Nigeria children. We measured the levels of malondialdehyde (MDA), a marker of lipid peroxidation and ascorbic acid in the plasma of 406 parasitaemic and 212 non-parasitaemic Nigerian children.

[Concentration of glutathione (GSH), ascorbic acid (vitamin C) and substances reacting with thiobarbituric acid (TBA-rs) in single human brain metastases].

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Dudek, Henryk; Farbiszewski, Ryszard; Rydzewska, Maria; Michno, Tadeusz; Kozłowski, Andrzej

2005-01-01

The aim of the study was to estimate the concentration of glutathione (GSH), ascorbic acid (vitamin C) and thiobarbituric acid (TBA-rs) in single human brain metastases and histologically unchanged nerve tissue. The research was conducted on fragments of neoplasmatic tissue collected from 45 patients undergoing surgery in the Department of Neurosurgery, Medical University of Białystok in years 1996-2002. Concentration of GSH was evaluated using the GSH-400 method, vitamin C using the method of Kyaw and TBA-rs using the method of Salaris and Babs. It has been found that there is a decrease of concentration of GSH and vitamin C and a considerable increase (p TBA-rs in investigated single brain human metastasis in correlation to the concentration of the mentioned above substances in unchanged nerve tissue.

Effect of dietary Satureja khuzistanica powder on semen characteristics and thiobarbituric acid reactive substances concentration in testicular tissue of Iranian native breeder rooster.

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2015-01-01

Because of a paucity of information on the effect of Satureja khuzistanica in male chickens, this study was undertaken to determine the influence of dietary S. khuzistanica powder (SKP) on seminal characteristics and testes thiobarbituric acid reactive substances (TBARS) content in Iranian native breeder rooster. Thirty-six 40-week-old roosters were randomly allotted to 3 equal groups and received either a basal diet without SKP (T1 or control), or a diet containing 20 g/kg (T2) and 40 g/kg (T3) of SKP for 8-week-long experimental period. Semen samples were obtained weekly by abdominal massage to evaluate the seminal characteristics. At the end of the eighth week 18 birds (6 birds per each group) were randomly slaughtered, and sample was taken from right testes for TBARS evaluation. Administration of SKP improved all semen traits, except for sperm concentration. Likewise, TBARS content in SKP treatments did not significantly differ from the control (P>0.05). Seminal volume, live sperm percentage and plasma membrane integrity percentage in SKP-treated groups were higher than the control. Conversely, abnormal sperm percentages reduced in SKP-treated groups (Prooster diet improves sperm quality and also reduces their sperm membrane lipid peroxidation, which may lead to higher fertilization rate.

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

International Nuclear Information System (INIS)

Pelle, E.; Maes, D.; Padulo, G.A.; Kim, E.K.; Smith, W.P.

1990-01-01

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

Protective effect of morin on lipid peroxidation and lipid profile in ammonium chloride-induced hyperammonemic rats

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S Subash

2012-04-01

Full Text Available Objective: To evaluated the protective effects of morin (3, 5, 7, 2', 4'-pentahydroxyflavone on lipid peroxidation and lipid levels during ammonium chloride (AC induced hyperammonemia in experimental rats. Methods: Thirty two male albino Wistar rats, which are weighing between 180-200 g were used for the study. The hyperammonemia was induced by administration of 100 mg/kg body weight (i.p. thrice in a week of AC for 8 weeks. Rats were treated with morin at dose (30 mg/kg body weight via intragastric intubations together with AC. At the end of experimental duration, blood ammonia, plasma urea, lipid peroxidation indices [thiobarbituric acid reactive substances, hydroperoxides and lipid levels (cholesterol, triglycerides, free fatty acids and phospholipids] in serum and tissues were analysed to evaluate the antiperoxidative and antilipidemic effects of morin. Results: Ammonia, urea, lipid peroxidative indices and lipid levels were significantly increased in AC administered group. Morin treatment resulted in positive modulation of ammonia, urea, lipid peroxidative indices and lipid levels. Morin administration to normal rats did not exhibit any significant changes in any of the parameters studied. Conclusions: It can be concluded that the beneficial effect of morin on ammonia, urea, lipid peroxidative indices and lipid levels could be due to its antioxidant property.

Modulatory effect of Scoparia dulcis in oxidative stress-induced lipid peroxidation in streptozotocin diabetic rats.

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Latha, M; Pari, L

2003-01-01

In light of evidence that diabetes mellitus is associated with oxidative stress and altered antioxidant status, we investigated the effect of Scoparia dulcis plant extracts (SPEt) (aqueous, ethanolic, and chloroform) in streptozotocin diabetic rats. Significant increases in the activities of insulin, superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, reduced glutathione, vitamin C, and vitamin E were observed in liver, kidney, and brain on treatment with SPEt. In addition, the treated groups also showed significant decreases in blood glucose, thiobarbituric acid-reactive substances, and hydroperoxide formation in tissues, suggesting its role in protection against lipid peroxidation-induced membrane damage. Thus, the results of the present study indicate that extracts of S. dulcis, especially the aqueous extract, showed a modulatory effect by attenuating the above lipid peroxidation in streptozotocin diabetes.

Effect of gamma irradiation on the lipid peroxidation in chicken, lamb and buffalo meat during chilled storage

International Nuclear Information System (INIS)

Kanatt, S.R.; Paul, P.; D'Souza, S.F.; Thomas, P.

1997-01-01

Chicken, lamb and buffalo meat were subjected to low-dose gamma irradiation (2.5 kGy) and stored at 0-3C. Lipid peroxidation in terms of thiobarbituric acid (TBA) number and carbonyl content were monitored during storage. While irradiated meat showed slight increase in TBA number and carbonyl content on storage as compared to nonirradiated meat, this did not affect the sensory qualities of meat. Free fatty acid content decreased markedly on irradiation. Irradiated meats were microbiologically safe and sensorily acceptable up to 4 weeks in the nonfrozen state (0-3C) while nonirradiated meat had a shelf-life of less than 2 weeks

Role of lipid peroxidation and oxidative stress in 3-methylindole pneumotoxicity

International Nuclear Information System (INIS)

Cary, M.G.

1985-01-01

The cytochrome P-450-catalyzed metabolism of 3-methylindole (3-MI) results in acute lung injury in ruminants and horses. Experiments were conducted to determine the role of lipid peroxidation and oxidative stress in 3-MI pneumotoxicity in goats. Goats were given methylethylketone peroxide (MEKP), a potent peroxidant, 3-MI, indole, or cremophor-EL vehicle. The levels of shortchain hydrocarbons in expired air were measured for 6 hours post-dosing by gas chromatography. Exhaled hydrocarbons increased 20 to 30 fold within 1 hour in goats given MEKP. No significant changes were seen in goats given 3-Mi, indole or cremophor-EL. Levels of thiobarbituric acid-reactive substances, an indicator of lipid peroxidation, were significantly increased in lung tissue from goats given MEKP. In goats given 3-MI, indole or cremophor-EL, the levels were not significantly different from each other. Goats were killed at 6 hours post-dosing and examined post mortem. Bronchiolar epithelial necrosis was seen in goats given 3-MI but there were not lung lesions in other groups. The role of oxygen radicals in 3-MI pneumotoxicity was examined in a goat lung explant system using 51 Cr release as an indicator of cytotoxicity. The results of these studies provide no evidence to support the view that 3-MI pneumotoxicity involves lipid peroxidation or oxidative stress as a result of formation of oxygen or xenobiotic radicals

High dietary level of synthetic vitamin E on lipid peroxidation, membrane fatty acid composition and cytotoxicity in breast cancer xenograft and in mouse host tissue

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Barnes Christopher J

2003-03-01

Full Text Available Abstract Background d-α-tocopherol is a naturally occurring form of vitamin E not previously known to have antitumor activity. Synthetic vitamin E (sE is a commonly used dietary supplement consisting of a mixture of d-α-tocopherol and 7 equimolar stereoisomers. To test for antilipid peroxidation and for antitumor activity of sE supplementation, two groups of nude mice bearing a MDA-MB 231 human breast cancer tumor were fed an AIN-76 diet, one with and one without an additional 2000 IU/kg dry food (equivalent to 900 mg of all-rac-α-tocopherol or sE. This provided an intake of about 200 mg/kg body weight per day. The mice were killed at either 2 or 6 weeks after the start of dietary intervention. During necropsy, tumor and host tissues were excised for histology and for biochemical analyses. Results Tumor growth was significantly reduced by 6 weeks of sE supplementation. Thiobarbituric acid reactive substances, an indicator of lipid peroxidation, were suppressed in tumor and in host tissues in sE supplemented mice. In the sE treated mice, the fatty acid composition of microsomal and mitochondrial membranes of tumor and host tissues had proportionately less linoleic acid (n-6 C 18-2, similar levels of arachidonic acid (n-6 C 20-4, but more docosahexanoic acid (n-3 C 22-6. The sE supplementation had no significant effect on blood counts or on intestinal histology but gave some evidence of cardiac toxicity as judged by myocyte vacuoles and by an indicator of oxidative stress (increased ratio of Mn SOD mRNA over GPX1 mRNA. Conclusions At least one of the stereoisomers in sE has antitumor activity. Synthetic vitamin E appears to preferentially stabilize membrane fatty acids with more double bonds in the acyl chain. Although sE suppressed tumor growth and lipid peroxidation, it may have side-effects in the heart.

Further investigations on the role of ascorbic acid in stratum corneum lipid models after UV exposure.

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Trommer, Hagen; Böttcher, Rolf; Huschka, Christoph; Wohlrab, Wolfgang; Neubert, Reinhard H H

2005-08-01

This study is the continuation of our research into vitamin C and its possible effects on human skin after topical administration. The effects of ascorbic acid, iron ions and UV irradiation on stratum corneum lipid models were investigated. The lipid models used were: a simple system (linolenic acid dispersion), a complex system (liposomes consisting of dipalmitoylphosphatidylcholine, cholesterol and linolenic acid) and complex systems with additionally incorporated ceramides (types III and IV). The lipid peroxidation was quantified by the thiobarbituric acid assay. A human adult low-calcium high-temperature (HaCaT) keratinocytes cell culture was used as a second in-vitro model. The amount of intracellular peroxides was determined by measuring the fluorescence intensity using the dihydrorhodamine 123 assay. Electron paramagnetic resonance spectroscopy was used to study the influence of ascorbic acid and iron ions on the signal intensity of 5-doxylstearic acid during UV exposure. Ascorbic acid showed prooxidative properties in the thiobarbituric acid assay whereas cell protection was measured in the HaCaT keratinocytes experiments. Electron paramagnetic resonance investigations revealed different extents of free radical production generated by iron ions, ascorbic acid and UV irradiation. In evaluating the results from this study new aspects of the mechanism of lipid damage caused by these three factors were suggested, transcending the simple redox behaviour of ascorbic acid.

Application of FTIR-ATR Spectroscopy to Determine the Extent of Lipid Peroxidation in Plasma during Haemodialysis

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Adam Oleszko

2015-01-01

Full Text Available During a haemodialysis (HD, because of the contact of blood with the surface of the dialyser, the immune system becomes activated and reactive oxygen species (ROS are released into plasma. Particularly exposed to the ROS are lipids and proteins contained in plasma, which undergo peroxidation. The main breakdown product of oxidized lipids is the malondialdehyde (MDA. A common method for measuring the concentration of MDA is a thiobarbituric acid reactive substances (TBARS method. Despite the formation of MDA in plasma during HD, its concentration decreases because it is removed from the blood in the dialyser. Therefore, this research proposes the Fourier Transform Infrared Attenuated Total Reflectance (FTIR-ATR spectroscopy, which enables determination of primary peroxidation products. We examined the influence of the amount of hydrogen peroxide added to lipid suspension that was earlier extracted from plasma specimen on lipid peroxidation with use of TBARS and FTIR-ATR methods. Linear correlation between these methods was shown. The proposed method was effective during the evaluation of changes in the extent of lipid peroxidation in plasma during a haemodialysis in sheep. A measurement using the FTIR-ATR showed an increase in plasma lipid peroxidation after 15 and 240 minutes of treatment, while the TBARS concentration was respectively lower.

Effects of particle size and heating time on thiobarbituric acid (TBA) test of soybean powder.

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Lee, Youn-Ju; Yoon, Won-Byong

2013-06-01

Effects of particle size and heating time during TBA test on the thiobarbituric acid reactive substance (TBARS) of soybean (Glycine Max) powder were studied. Effects of processing variables involved in the pulverization of soybean, such as the temperature of soybean powder, the oxygen level in the vessel, and the pulverisation time, were investigated. The temperature of the soybean powder and the oxygen level had no significant influence on the TBARS (pTBA test significantly affected the TBARS. Change of TBARS during heating was well described by the fractional conversion first order kinetics model. A diffusion model was introduced to quantify the effect of particle size on TBARS. The major finding of this study was that the TBA test to estimate the level of the lipid oxidation directly from powders should consider the heating time and the mean particle sizes of the sample. Copyright © 2012 Elsevier Ltd. All rights reserved.

Chemo-enzymatic epoxidation of olefins by carboxylic acid esters and hydrogen peroxide

Energy Technology Data Exchange (ETDEWEB)

Ruesch gen. Klaas, M.; Warwel, S. [Inst. for Biochemistry and Technology of Lipids, H.P. Kaufmanm-Inst., Federal Centre for Cereal, Potato and Lipid Research, Muenster (Germany)

1998-12-31

Ethylen and, recently, butadiene can be epoxidized directly with oxygen and for the epoxidation of propylene, the use of heterogeneous transition metals and organic peroxides (Halcon-Process) is the major player. But, beside from those notable exceptions, all other epoxidations, including large ones like the epoxidation of plant oils as PVC-stabilizers (about 200.000 t/year), are carried out with peroxy acids. Because mcpba is far to expensive for most applications, short chain peracids like peracetic acid are used. Being much less stable than mcpba and thus risky handled in large amounts and high concentrations, these peroxy acids were preferably prepared in-situ. However, conventional in-situ formation of peracids has the serious drawback, that a strong acid is necessary to catalyze peroxy acid formation from the carboxylic acid and hydrogen peroxide. The presence of a strong acid in the reaction mixture often results in decreased selectivity because of the formation of undesired by-products by opening of the oxirane ring. Therefore, we propose a new method for epoxidation based on the in-situ preparation of percarboxylic acids from carboxylic acid esters and hydrogen peroxide catalyzed by a commercial, immobilized lipase. (orig.)

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

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

2014-01-01

The antioxidant properties of ethanolic root extract of pepper fruit (Donnetia tripetala), and its effect on lipid peroxidation of some fresh beef tissues during frozen storage were investigated. The antioxidant parameters were assessed using standard methods, while malondialdehyde levels of different fresh beef tissue sections treated with the extract prior to freezing, were estimated in a colorimetric reaction with thiobarbituric acid. The H2O2-scavenging ability of the extract was similar to that of ascorbic acid, with a maximum scavenging power of 55.61 ±4.98%, and an IC50 value of 86µg/ml. The extract exhibited a concentration-dependent ferric ion-reducing power, although this was significantly lower relative to that of the ascorbic acid (p capacity of the extract to inhibit lipid peroxidation in frozen heart muscle slices was significantly higher than that of vitamin C (p extract of D. tripetala is rich in antioxidants which can be applied to meat preservation during refrigerated storage.

Lipid peroxidation analysis in salmon (Salmo salar L.) processed by e-beam

International Nuclear Information System (INIS)

Thomaz, Fernanda S.; Trindade, Reginaldo A.; Fanaro, Gustavo B.; Araujo, Michel M.; Villavicencio, Ana Lucia C.H.; Mancini-Filho, Jorge

2007-01-01

In Brazil the consumption of fish is relatively small when compared with other source of meat protein. However the diets rich in fish have association with a wide range of positive health effects, due your great deal the fat acids omega 3, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Salmon (Salmo salar L.) specifically have those fat acids in main quantity. The omega 3 fat acids are related to the prevention of several not transmissible illness; with emphasis to cardiovascular, hypertriglyceridemia, cancer, osteoporosis and inflammatory and anti immune diseases. Food borne illnesses have been a growing concern to the governments, producers and consumers, mainly regarding the damages they cause to human health. In this context, irradiation is used as a method to preserve food. The present work aim to evaluate the lipid peroxidation in natura salmon filet irradiated on the basis of thiobarbituric acid reactive substances (TBARS). Samples were irradiated in an e beam accelerator (Radiation Dynamics Co. model JOB, New York, USA), 1,5 MeV-25mA at doses of 0, 1.0 and 2.0 kGy, analyzed 7, 15, 21, 30 e 45 days after irradiation. Irradiated samples analyzed during a 45 day period, showed a higher lipid peroxidation than the control samples at the same period, increasing with dose and storage time. However, it did not pass the permitted value. Irradiation demonstrated effective without compromising the quality of the food. (author)

Lipid peroxidation analysis in salmon (Salmo salar L.) processed by e-beam

Energy Technology Data Exchange (ETDEWEB)

Thomaz, Fernanda S.; Trindade, Reginaldo A.; Fanaro, Gustavo B.; Araujo, Michel M.; Villavicencio, Ana Lucia C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: villavic@ipen.br; Mancini-Filho, Jorge [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: jmancini@usp.br

2007-07-01

In Brazil the consumption of fish is relatively small when compared with other source of meat protein. However the diets rich in fish have association with a wide range of positive health effects, due your great deal the fat acids omega 3, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Salmon (Salmo salar L.) specifically have those fat acids in main quantity. The omega 3 fat acids are related to the prevention of several not transmissible illness; with emphasis to cardiovascular, hypertriglyceridemia, cancer, osteoporosis and inflammatory and anti immune diseases. Food borne illnesses have been a growing concern to the governments, producers and consumers, mainly regarding the damages they cause to human health. In this context, irradiation is used as a method to preserve food. The present work aim to evaluate the lipid peroxidation in natura salmon filet irradiated on the basis of thiobarbituric acid reactive substances (TBARS). Samples were irradiated in an e beam accelerator (Radiation Dynamics Co. model JOB, New York, USA), 1,5 MeV-25mA at doses of 0, 1.0 and 2.0 kGy, analyzed 7, 15, 21, 30 e 45 days after irradiation. Irradiated samples analyzed during a 45 day period, showed a higher lipid peroxidation than the control samples at the same period, increasing with dose and storage time. However, it did not pass the permitted value. Irradiation demonstrated effective without compromising the quality of the food. (author)

One barbiturate and two solvated thiobarbiturates containing the triply hydrogen-bonded ADA/DAD synthon, plus one ansolvate and three solvates of their coformer 2,4-diaminopyrimidine.

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Hützler, Wilhelm Maximilian; Egert, Ernst; Bolte, Michael

2016-09-01

A path to new synthons for application in crystal engineering is the replacement of a strong hydrogen-bond acceptor, like a C=O group, with a weaker acceptor, like a C=S group, in doubly or triply hydrogen-bonded synthons. For instance, if the C=O group at the 2-position of barbituric acid is changed into a C=S group, 2-thiobarbituric acid is obtained. Each of the compounds comprises two ADA hydrogen-bonding sites (D = donor and A = acceptor). We report the results of cocrystallization experiments of barbituric acid and 2-thiobarbituric acid, respectively, with 2,4-diaminopyrimidine, which contains a complementary DAD hydrogen-bonding site and is therefore capable of forming an ADA/DAD synthon with barbituric acid and 2-thiobarbituric acid. In addition, pure 2,4-diaminopyrimidine was crystallized in order to study its preferred hydrogen-bonding motifs. The experiments yielded one ansolvate of 2,4-diaminopyrimidine (pyrimidine-2,4-diamine, DAPY), C4H6N4, (I), three solvates of DAPY, namely 2,4-diaminopyrimidine-1,4-dioxane (2/1), 2C4H6N4·C4H8O2, (II), 2,4-diaminopyrimidine-N,N-dimethylacetamide (1/1), C4H6N4·C4H9NO, (III), and 2,4-diaminopyrimidine-1-methylpyrrolidin-2-one (1/1), C4H6N4·C5H9NO, (IV), one salt of barbituric acid, viz. 2,4-diaminopyrimidinium barbiturate (barbiturate is 2,4,6-trioxopyrimidin-5-ide), C4H7N4(+)·C4H3N2O3(-), (V), and two solvated salts of 2-thiobarbituric acid, viz. 2,4-diaminopyrimidinium 2-thiobarbiturate-N,N-dimethylformamide (1/2) (2-thiobarbiturate is 4,6-dioxo-2-sulfanylidenepyrimidin-5-ide), C4H7N4(+)·C4H3N2O2S(-)·2C3H7NO, (VI), and 2,4-diaminopyrimidinium 2-thiobarbiturate-N,N-dimethylacetamide (1/2), C4H7N4(+)·C4H3N2O2S(-)·2C4H9NO, (VII). The ADA/DAD synthon was succesfully formed in the salt of barbituric acid, i.e. (V), as well as in the salts of 2-thiobarbituric acid, i.e. (VI) and (VII). In the crystal structures of 2,4-diaminopyrimidine, i.e. (I)-(IV), R2(2)(8) N-H...N hydrogen-bond motifs are preferred and, in two

Cytoprotective effect of tocopherols in hepatocytes cultured with polyunsaturated fatty acids

DEFF Research Database (Denmark)

Mikkelsen, L.; Hansen, Harald S.; Grunnet, N.

1994-01-01

When highly unsaturated fatty acids are added to cell cultures, it can become important to include antioxidants in the culture medium to prevent cytotoxic peroxidation. To find an optimal antioxidant for this purpose, the effect of 50 µM a-tocopherol, ¿-tocopherol, a-tocopheryl acetate, a...... of thiobarbituric acid reactive substances in the cultures was also measured. a-Tocopheryl acid succinate was found to be the most effective cytoprotective compound, followed by N,N'-diphenyl-1,4-phenylenediamine, a- tocopherol, ¿-tocopherol and a-tocopheryl acetate, and a-tocopheryl phosphate was without effect....

Synergism between hydrogen peroxide and seventeen acids against six bacterial strains.

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Martin, H; Maris, P

2012-09-01

The objective of this study was to evaluate the bactericidal efficacy of hydrogen peroxide administered in combination with 17 mineral and organic acids authorized for use in the food industry. The assays were performed on a 96-well microplate using a microdilution technique based on the checkerboard titration method. The six selected strains were reference strains and strains representative of contaminating bacteria in the food industry. Each synergistic hydrogen peroxide/acid combination found after 5-min contact time at 20°C in distilled water was then tested in conditions simulating four different use conditions. Thirty-two combinations were synergistic in distilled water; twenty-five of these remained synergistic with one or more of the four mineral and organic interfering substances selected. Hydrogen peroxide/formic acid combination was synergistic for all six bacterial strains in distilled water and remained synergistic with interfering substances. Six other combinations maintained their synergistic effect in the presence of an organic load but only for one or two bacterial strains. Synergistic combinations of disinfectants were revealed, among them the promising hydrogen peroxide/formic acid combination. A rapid screening method was proposed and used to reveal the synergistic potential of disinfectant and/or sanitizer combinations. © 2012 ANSES Fougères Laboratory Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

Stabilization of hydrogen peroxide using tartaric acids in Fenton and fenton-like oxidation

Energy Technology Data Exchange (ETDEWEB)

Oh, Hyung Suk; Kim, Jeong-Jin; Kim, Young-Hun [Andong National University, Andong (Korea, Republic of)

2016-03-15

The stabilization of hydrogen peroxide is a key factor in the efficiency of a Fenton reaction. The stability of hydrogen peroxide was evaluated in a Fenton reaction and Fenton-like reactions in the presence of tartaric acid as a stabilizer. The interactions between ferrous or ferric iron and tartaric acid were observed through spectroscopic monitoring at variable pH around pKa{sub 1} and pKa{sub 2} of the stabilizer. Ferric iron had a strong interaction with the stabilizer, and the strong interaction was dominant above pKa{sub 2}. At a low pH, below pKa{sub 1}, the stabilizing effect was at its maximum and the prolonged life-time of hydrogen peroxide gave a higher efficiency to the oxidative degradation of nitrobenzene. In Fenton-like reactions with hematite, the acidic conditions caused dissolution of iron from an iron oxide, and an increase in iron species was the result. Tartaric acid showed a stabilizing effect on hydrogen peroxide in the Fentonlike system. The stabilization by tartaric acid might be due to an inhibition of catalytic activity of dissolved iron, and the stabilization strongly depends on the ionization state of the stabilizer.

Stabilization of hydrogen peroxide using tartaric acids in Fenton and fenton-like oxidation

International Nuclear Information System (INIS)

Oh, Hyung Suk; Kim, Jeong-Jin; Kim, Young-Hun

2016-01-01

The stabilization of hydrogen peroxide is a key factor in the efficiency of a Fenton reaction. The stability of hydrogen peroxide was evaluated in a Fenton reaction and Fenton-like reactions in the presence of tartaric acid as a stabilizer. The interactions between ferrous or ferric iron and tartaric acid were observed through spectroscopic monitoring at variable pH around pKa 1 and pKa 2 of the stabilizer. Ferric iron had a strong interaction with the stabilizer, and the strong interaction was dominant above pKa 2 . At a low pH, below pKa 1 , the stabilizing effect was at its maximum and the prolonged life-time of hydrogen peroxide gave a higher efficiency to the oxidative degradation of nitrobenzene. In Fenton-like reactions with hematite, the acidic conditions caused dissolution of iron from an iron oxide, and an increase in iron species was the result. Tartaric acid showed a stabilizing effect on hydrogen peroxide in the Fentonlike system. The stabilization by tartaric acid might be due to an inhibition of catalytic activity of dissolved iron, and the stabilization strongly depends on the ionization state of the stabilizer.

Determination of peracetic acid and hydrogen peroxide in the mixture

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Bodiroga Milanka

2002-01-01

Full Text Available Iodometric and permanganometric titrations were used for determination of peracetic acid and hydrogen peroxide (H2O2 in the mixture. Two procedures were described and compared. Titrations could be done in only one vessel, in the same reaction mixture, when iodometric titration of peracetic acid was continued after the permanganometric titration of H2O2, (procedure A. Peracetic acid and H2O2, as oxidizing agents, reacted with potassium iodide in an acid medium, evolving iodine. This reaction was used for the quantitative iodometric determination of total peroxide in procedure B. H2O2 reacted with potassium permanganate in acid medium, but peracetic acid did not react under the same conditions. That made possible the selective permanganometric determination of H2O2 in the presence of peracetic acid. The procedure B was performed in two titration vessels (KV=3.4% for peracetic acid, 0.6% for H2O2. The procedure A for iodometric determination of peracetic acid in one titration vessel after permanganometric titration of H2O2 was recommended (KV=2,5% for peracetic acid, 0,45% for H2O2.

Interrelationships between lipid peroxidation and total antioxidant status in sedentary controls and unprofessional athletes.

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Caimi, Gregorio; Canino, Baldassare; Lo Presti, Rosalia

2010-01-01

We examined the thiobarbituric acid-reactive substances (TBARS) as an index of lipid peroxidation, and the total antioxidant status (TAS) in 81 unprofessional athletes subdivided into three subgroups. The first group included 28 subjects who practised endurance sports, the second included 30 subjects who practised mixed sports, the third included 23 subjects who practised power sports. We enrolled also a group of 61 sedentary controls (SC). TBARS were increased and TAS was decreased in the whole group of athletes in comparison with SC; an almost similar behaviour was present also subdividing athletes according to the practised sport. A significant negative correlation between these two parameters emerged in SC but not in the whole group of athletes. Unless for the athletes that practised endurance sports a similar trend was found in athletes that practised mixed and power sports. In conclusion, at rest the symmetrical behaviour between the lipid peroxidation increase and the TAS decrease, observed in sedentary controls, was not evident in unprofessional athletes who practised different sports.

Study on The Potency of Methanol Extracts From Xanthosoma nigrum Stellfeld As Natural Anti Oxidant by Thiobarbituric Acid Method

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Devi Ratnawati

2013-12-01

Full Text Available In this research Xanthosoma nigrum Stellfeld (the Purple yam was selected as experimental material. This plant was collected from Rejang Lebong region, Bengkulu Province. Methanol extract 96% from stem of purple yam was studied its anti-oxidant activity in various concentrations with α-tocopherol (200 ppm as standard of antioxidant. Antioxidant activity was determined using Thiobarbituric Acid (TBA method. Linoleic acid was oxidized at 40 ºC for seven days with or without extract and the final product malondialdehyde (MDA was reacted with thiostembituric acid to be of red colored complex (MDA-TBA and was then measured by UV-VIS spectrophotometer at λ 532 nm. Stem extract of purple yam with concentration of 100 ppm, 150 ppm, 200 ppm and 300 ppm respectively had the inhibition of 19.32%, 21.85%, 29.47%, and 31.05%. α-Tocopherol as positive control which showed inhibition ability of 85.14% at 200 ppm. Based on the result obtained in this study, the stem’s extract of Purpel yam plant showed that antioxidant activity was lower than α-tocopherol.

Determination of concentration and molar absorptivity of hypochlorous acid and hypobromous acid species by hydrogen peroxide titration

Science.gov (United States)

Uehara, H.; Arakaki, T.

2017-12-01

Hypochlorous acid and hypobromous acid (abbreviated as "HypoX acids") are the main ingredients of bleaching and bactericides. The HypoX acids change their chemical forms depending on environmental factors such as pH and various chemical reactions. For example, it has been reported that hypobromite ion in water changes to carcinogenic bromate by photochemical reaction with ultraviolet light. In this study, concentrations of HypoX acids were determined by UV-VIS absorbance measurement utilizing the fact that HypoX acids react with hydrogen peroxide and do not co-exist in the solution. The method for determining the concentration by titration with hydrogen peroxide can be carried out simpler and more efficiently than the DPD method or the current titration method generally used for chlorine concentration measurement. Molar absorptivity between 250 - 500 nm of HypoX acids, including their conjugate base species, was determined by solving theoretical acid-base formula including molar fraction of each chemical species at various pHs. Molar absorptivity of OCl- and OBr- between 250 - 500 nm was determined based on the concentrations obtained from titration with hydrogen peroxide and absorbance at pH > 10, where OCl- and OBr- dominate. Furthermore, the HypoX acids solutions were irradiated with a solar simulator, and the photolysis rate constants were obtained. Based on those values, the half-lives were calculated and the behavior of HypoX acids in the environment was elucidated.

Nitrophenylboronic acids as highly chemoselective probes to detect hydrogen peroxide in foods and agricultural products.

Science.gov (United States)

Lu, Chun-Ping; Lin, Chieh-Ti; Chang, Ching-Ming; Wu, Shih-Hsiung; Lo, Lee-Chiang

2011-11-09

Hydrogen peroxide is commonly used in the food processing industry as a chlorine-free bleaching and sterilizing agent, but excessive amounts of residual hydrogen peroxide have led to cases of food poisoning. Here we describe the development of a novel nonenzymatic colorimetric method for the determination of residual hydrogen peroxide in foods and agricultural products. Nitrophenylboronic acids chemoselectively react with hydrogen peroxide under alkaline conditions to produce yellow nitrophenolates. Of the three nitrophenylboronic acid isomers tested, the p-isomer displayed the highest sensitivity for hydrogen peroxide and the fastest reaction kinetics. The reaction product, p-nitrophenolate, has an absorption maximum at 405 nm and a good linear correlation between the hydrogen peroxide concentration and the A(405) values was obtained. We successfully applied this convenient and rapid method for hydrogen peroxide determination to samples of dried bean curds and disposable chopsticks, thereby demonstrating its potential in foods and agricultural industries.

Inhibition of rat microsomal lipid peroxidation by the oral administration of D002

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Menéndez R.

2000-01-01

Full Text Available The effect of D002, a defined mixture of higher primary alcohols purified from bee wax, on in vivo and in vitro lipid peroxidation was studied. The extent of lipid peroxidation was measured on the basis of the levels of thiobarbituric acid reactive substances (TBARS. When D002 (5-100 mg/kg body weight was administered orally to rats for two weeks, a partial inhibition of the in vitro enzymatic and non-enzymatic lipid peroxidation was observed in liver and brain microsomes. Maximal protection (46% occurred at a dose of 25 mg/kg. D002 behaved differently depending on both the presence of NADPH and the integrity of liver microsomes, which suggests that under conditions where microsomal metabolism was favored the protective effect of D002 was increased. D002 (25 mg/kg also completely inhibited carbon tetrachloride- and toluene-induced in vivo lipid peroxidation in liver and brain. Also, D002 significantly lowered in a dose-dependent manner the basal level of TBARS in liver (19-40% and brain (28-44% microsomes. We conclude that the oral administration of D002 (5, 25 and 100 mg/kg for two weeks protected rat liver and brain microsomes against microsomal lipid peroxidation in vitro and in vivo. Thus, D002 could be useful as a dietary natural antioxidant supplement. More studies are required before these data can be extrapolated to the recommendation for the use of D002 as a dietary antioxidant supplement for humans.

Inhibition of lipid peroxidation induced by γ- radiation and AAPH in rat liver and brain mitochondria by mushrooms

International Nuclear Information System (INIS)

Lakshmi, B.; Janardhanan, K.K.; Tilak, J.C.; Devasagayam, T.P.A.; Adhikari, S.

2005-01-01

Exposure to radiation or 2.2' Azobis(2-amidopropane) dihydrochloride (AAPH) induces generation of reactive oxygen species (ROS) especially hydroxyl radical ( . OH) and peroxyl radical (ROO . ), which are capable of inducing lipid peroxidation. Our earlier studies have demonstrated that extracts of the medicinal and edible mushrooms Ganoderma lucidum, Pleurotus florida, Pleurotus sajor-caju and Phellinus rimosus possessed significant antioxidant activity, measured as radical scavenging. In the present study, we examined the protective effect of these mushroom extracts against radiation- and AAPH-induced lipid peroxidation using rat liver and brain mitochondria as model systems. The results obtained showed that the investigated mushroom extracts significantly inhibited the formation of lipid hydroperoxide and thiobarbituric acid reactive substances, indicating membrane protective effects. The finding suggests the profound protective effect of the extracts of the fruiting bodies of G. lucidum, P. florida, P. sajor-caju and P. rimosus against lipid peroxidation by two major forms of ROS capable of inducing this type of damage in a major organelle, the mitochondria from both rat liver and brain. This observation can possibly explain the health benefits of these mushrooms. (author)

Influence of dihydroquercetin on the lipid peroxidation of mice during post-radiation period

Energy Technology Data Exchange (ETDEWEB)

Teselkin, Yu. O.; Babenkova, I. V.; Tjukavkina, N. A.; Rulenko, I. A.; Kolesnik, Yu. A.; Kolhir, V. K.; Eichholz, A. A. [Department of Biophysics, Russian Medical University, Ostrovityanova Street 1, Moscow 117869 (Russian Federation)

1998-07-01

The effect of the natural antioxidant dihydroquercetin was examined on the process of free radical oxidation of serum and liver lipids of mice, after a single 4 Gy dose of γ-irradiation. The content of lipid peroxidation products reacting with thiobarbituric acid in irradiated animals receiving oral dihydroquercetin (experimental) for 155 days after irradiation was significantly lower compared with animals receiving irradiation and no antioxidant (controls). The intensity of Fe{sup 2+}-induced chemiluminescence of liver homogenates of experimental mice was lower by the end of the experiment (p < 0.001) than the chemiluminescence of liver homogenates of both control and intact animals. It is assumed that this was due to the preferential uptake of dihydroquercetin by the liver. (author)

MOLYBDENUM CATALYZED ACID PEROXIDE BLEACHING OF EUCALYPTUS KRAFT PULP

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Marcos S. Rabelo

2008-08-01

Full Text Available Molybdenum catalyzed peroxide bleaching (PMo Stage consists of pulp treatment with hydrogen peroxide under acidic conditions in the presence of a molybdenum catalyst. Molybdenum is applied in catalytic doses (50-200 mg/kg pulp and may originate from various sources, including (NH46Mo7O24.4H2O, Na2MoO4.2H2O, siliconmolybdate, etc. This work is aimed at optimizing the PMo stage and evaluating its industrial application in the OAZDP sequence. Optimum PMo stage conditions for bleaching eucalyptus pulp were 90 ºC, pH 3.5, 2 h, 0.1 kg/adt Mo and 5 kg/adt H2O2. The PMo stage was more efficient to remove pulp hexenuronic acids than lignin. Its efficiency decreased with increasing pH in the range of 1.5-5.5, while it increased with increasing temperature and peroxide and molybdenum doses. The application of the PMo stage as replacement for the A-stage of the AZDP sequence significantly decreased chlorine dioxide demand. The PMo stage caused a decrease of 20-30% in the generation of organically bound chlorine. The quality parameters of the pulp produced during the PMo stage mill trial were comparable to those obtained with the reference A-stage.

Effect of soy sauce on lipid oxidation of irradiated pork patties

Science.gov (United States)

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

2013-09-01

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

Effect of foliar application of salicylic acid, hydrogen peroxide

Indian Academy of Sciences (India)

Home; Journals; Journal of Biosciences; Volume 42; Issue 2. Effect of foliar application of salicylic acid, hydrogen peroxide and a xyloglucan oligosaccharide on capsiate content and gene expression associatedwith capsinoids synthesis in Capsicum annuum L. AY ZUNUN-PÉREZ T GUEVARA-FIGUEROA SN ...

Role of lipid peroxidation in pathogenesis of senile cataract

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Kisić Bojana

2009-01-01

Full Text Available Background /Aim. Cataract is a structural, biochemical and optical change in the eye lens, which changes transmission and refraction of light rays reducing keenness and clarity of a figure on the retina. Its occurrence is highest in older people, over the age of 65 (45.9%, thus a certain degree of opacification exists practically in all people over the 70. Our research was directed to measuring of lipid peroxidation products in cataract lenses involved in early stages of cataractogenesis through oxidative stress and in the development of mature cataract. Methods. Clinical and biochemical research was carried out in 101 patients with cataract, 46 women and 55 men. The average age of the group was 72.47 (ґ = 7.98. According to the cataract maturity degree the patients were classified into two groups as follows: cataracta senilis incipiens (n = 41 and cataracta senilis matura (n = 60. Measuring of diene conjugates was carried out by spectrophotometer. Fluorescent lipid peroxidation products were measured by a spectrofluorophotometer, and malondialdehyde (MDA concentration was measured by colorimeter as a product of a reaction with thiobarbituric acid (TBA. Result. Significantly higher diene conjugated concentration in lenses was measured in the patients with the diagnosis cataracta senilis incipiens (p < 0.001 as well as the intensity of fluorescent iminopropens (p < 0.001. Significantly higher MDA concentration in lens (p < 0.001 was measured in the patients with cataracta senilis matura. Conclusion. The lens structure changes caused by lipid peroxidation can, with other risk factors present, influence the occurrence and development of mature cataract. Some cataract types show different lipid peroxidation intensity with the most distinct changes in cataract which started as corticonuclear.

Determination of peracetic acid and hydrogen peroxide in the mixture

OpenAIRE

Bodiroga Milanka; Ognjanović Jasminka

2002-01-01

Iodometric and permanganometric titrations were used for determination of peracetic acid and hydrogen peroxide (H2O2) in the mixture. Two procedures were described and compared. Titrations could be done in only one vessel, in the same reaction mixture, when iodometric titration of peracetic acid was continued after the permanganometric titration of H2O2, (procedure A). Peracetic acid and H2O2, as oxidizing agents, reacted with potassium iodide in an acid medium, evolving iodine. This reaction...

Effects of Rhus coriaria on nutrient composition, thiobarbituric acid ...

African Journals Online (AJOL)

Heat stress negatively affects the meat quality in broiler chickens, as indicated by lipid peroxidation. The aim of this study was to investigate the effects of 0.0, 2.5, 5.0 and 10 g sumac fruit powder/kg of the diet, along with 100 mg α-tocopherol acetate (AT)/kg as antioxidants, on meat characteristics of broilers under heat ...

A high-throughput microtiter plate based method for the determination of peracetic acid and hydrogen peroxide.

Science.gov (United States)

Putt, Karson S; Pugh, Randall B

2013-01-01

Peracetic acid is gaining usage in numerous industries who have found a myriad of uses for its antimicrobial activity. However, rapid high throughput quantitation methods for peracetic acid and hydrogen peroxide are lacking. Herein, we describe the development of a high-throughput microtiter plate based assay based upon the well known and trusted titration chemical reactions. The adaptation of these titration chemistries to rapid plate based absorbance methods for the sequential determination of hydrogen peroxide specifically and the total amount of peroxides present in solution are described. The results of these methods were compared to those of a standard titration and found to be in good agreement. Additionally, the utility of the developed method is demonstrated through the generation of degradation curves of both peracetic acid and hydrogen peroxide in a mixed solution.

Thiobarbiturate and barbiturate salts of pefloxacin drug: Growth, structure, thermal stability and IR-spectra

Science.gov (United States)

Golovnev, Nicolay N.; Molokeev, Maxim S.; Lesnikov, Maxim K.; Sterkhova, Irina V.; Atuchin, Victor V.

2017-12-01

Three new salts of pefloxacin (PefH) with thiobarbituric (H2tba) and barbituric (H2ba) acids, pefloxacinium 2-thiobarbiturate trihydrate, PefH2(Htba)·3H2O (1), pefloxacinium 2-thiobarbiturate, PefH2(Htba) (2) and bis(pefloxacinium barbiturate) hydrate, (PefH2)2(Hba)2·2.56H2O (3) are synthesized and structurally characterized by the X-ray single-crystal diffraction. The structures of 1-3 contain intramolecular hydrogen bonds Csbnd H⋯F, Osbnd H⋯O. Intermolecular hydrogen bonds Nsbnd H⋯O and Osbnd H⋯O form a 2D plane network in 1. In 2 and 3, intermolecular hydrogen bonds Nsbnd H⋯O form the infinite chains. In 1-3, the Htba- and Hba- ions are connected with PefH2+ only by one intermolecular hydrogen bond Nsbnd H⋯O. In 2 and 3, two Htba- and Hba- ions are connected by two hydrogen bonds Nsbnd H⋯O. These pairs form infinite chains. All three structures are stabilized by the π-π interactions of the head-to-tail type between PefH2+ ions. Compounds 2 and 3 are characterized by powder XRD, TG-DSC and FT-IR.

Mechanism of ascorbic acid interference in biochemical tests that use peroxide and peroxidase to generate chromophore.

Science.gov (United States)

Martinello, Flávia; Luiz da Silva, Edson

2006-11-01

Ascorbic acid interferes negatively in peroxidase-based tests (Trinder method). However, the precise mechanism remains unclear for tests that use peroxide, a phenolic compound and 4-aminophenazone (4-AP). We determined the chemical mechanism of this interference, by examining the effects of ascorbic acid in the reaction kinetics of the production and reduction of the oxidized chromophore in urate, cholesterol, triglyceride and glucose tests. Reaction of ascorbic acid with the Trinder method constituents was also verified. Ascorbic acid interfered stoichiometrically with all tests studied. However, it had two distinct effects on the reaction rate. In the urate test, ascorbic acid decreased the chromophore formation with no change in its production kinetics. In contrast, in cholesterol, triglyceride and glucose tests, an increase in the lag phase of color development occurred. Of all the Trinder constituents, only peroxide reverted the interference. In addition, ascorbic acid did not interfere with oxidase activity nor reduce significantly the chromophore formed. Peroxide depletion was the predominant chemical mechanism of ascorbic acid interference in the Trinder method with phenolics and 4-AP. Distinctive effects of ascorbic acid on the reaction kinetics of urate, cholesterol, glucose and triglyceride might be due to the rate of peroxide production by oxidases.

COMPARATIVE EFFICIENCY OF DIFFERENT ANTIOXIDANTS ON FAT STABILITY IN BROILER RATIONS: THIOBARBITURIC ACID VALUES

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Ghulam Mustafa, Fawad Ahmad, Arfan Yousaf and Asad Ullah Hyder

2002-04-01

Full Text Available Thiobarbituric acid (TBA value was significantly (P< 0.05 affected by storage period, fat levels and antioxidants but the interaction of these factors was non significant. TBA value increased with the increase in storage period, however, the increase was relatively less during first 14 days of storage then a significant increase in TBA was observed as the storage period prolonged. Rations containing 4% fat have greater TBA value than the rations containing 2 or 3% fat. There was also a significant difference on TBA value due to antioxidant and their levels. TBA value was lower in the rations containing ethoxyquin than BHT containing rations and the rations supplemented with oxistat had greater TBA value. At higher level of any antioxidant, TBA value decreased, however, the difference between TBA values at both levels is non significant. With the increase in storage period there was increase in TBA value at both the antioxidant level. Antioxidant had a significant effect on fat stability in TBA test. Antioxidant level at 2 and 3% fat had a non significant effect but at 4% fat level. Antioxidant level had a significant effect. However, TBA values increased significantly at both levels of antioxidant with the increase in fat levels.

New Diethyl Ammonium Salt of Thiobarbituric Acid Derivative: Synthesis, Molecular Structure Investigations and Docking Studies

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Assem Barakat

2015-11-01

Full Text Available The synthesis of the new diethyl ammonium salt of diethylammonium(E-5-(1,5-bis(4-fluorophenyl-3-oxopent-4-en-1-yl-1,3-diethyl-4,6-dioxo-2-thioxohexaydropyrimidin-5-ide 3 via a regioselective Michael addition of N,N-diethylthiobarbituric acid 1 to dienone 2 is described. In 3, the carboanion of the thiobarbituric moiety is stabilized by the strong intramolecular electron delocalization with the adjacent carbonyl groups and so the reaction proceeds without any cyclization. The molecular structure investigations of 3 were determined by single-crystal X-ray diffraction as well as DFT computations. The theoretically calculated (DFT/B3LYP geometry agrees well with the crystallographic data. The effect of fluorine replacement by chlorine atoms on the molecular structure aspects were investigated using DFT methods. Calculated electronic spectra showed a bathochromic shift of the π-π* transition when fluorine is replaced by chlorine. Charge decomposition analyses were performed to study possible interaction between the different fragments in the studied systems. Molecular docking simulations examining the inhibitory nature of the compound show an anti-diabetic activity with Pa (probability of activity value of 0.229.

A high-throughput microtiter plate based method for the determination of peracetic acid and hydrogen peroxide.

Directory of Open Access Journals (Sweden)

Karson S Putt

Full Text Available Peracetic acid is gaining usage in numerous industries who have found a myriad of uses for its antimicrobial activity. However, rapid high throughput quantitation methods for peracetic acid and hydrogen peroxide are lacking. Herein, we describe the development of a high-throughput microtiter plate based assay based upon the well known and trusted titration chemical reactions. The adaptation of these titration chemistries to rapid plate based absorbance methods for the sequential determination of hydrogen peroxide specifically and the total amount of peroxides present in solution are described. The results of these methods were compared to those of a standard titration and found to be in good agreement. Additionally, the utility of the developed method is demonstrated through the generation of degradation curves of both peracetic acid and hydrogen peroxide in a mixed solution.

Oxidation of hydrogen peroxide by [Ni (cyclam)] in aqueous acidic ...

Indian Academy of Sciences (India)

Oxidation of hydrogen peroxide by tris(2,2 -bipyridine) and tris(4,4 -dimethyl-2,2 - bipyridine) complexes of osmium(III), iron(III), ruthenium(III), and nickel(III) studied in acidic and neutral aqueous media, show an inverse acid depen- dence over the pH the range 6.0–8.5.12 Kinetic mea- surements with an excess of H2O2 ...

In vitro evaluation of peroxyl radical scavenging capacity of water ...

African Journals Online (AJOL)

STORAGESEVER

2009-04-06

Apr 6, 2009 ... ... phenolics viz. condensed tannin and phlobatannin, gallic acid, protocatechuic acid pyrocatechol, (+)- ... Lipid peroxidation by thiobarbituric acid assay (TBA). TBA reacts with .... Antifungal activity of polyphenolic complex of ...

Algerian mint species：high performance thin layer chromatography quantitative determination of rosmarinic acid and in vitro inhibitory effects on linoleic acid peroxidation

Institute of Scientific and Technical Information of China (English)

Brahmi Fatiha; Madani Khodir; Stvigny Caroline; Chibane Mohamed; Duez Pierre

2014-01-01

Objective: To determine the quantitative paremeters of rosmarinic acid in Algerian mints,Mentha spicata L. (M. spicata), Mentha pulegium L. and Mentha rotundifolia (L.) Huds by high performance thin layer chromatography (HPTLC)-densitometric method and screen the effects of these plant extracts on linoleic acid peroxidation.Methods:The analyses were performed on HPTLC silica gel 60 F254 plates with chloroform:acetone: formic acid (75:16.5:8.5, v/v) as the mobile phase. Rosmarinic acid was determined in UV at 365 nm and fluorescence at λexc 325 nm with a 550 nm filter, respectively. The effects of plants extracts on linoleic acid peroxidation were measured by an indirect in vitro colorimetric method.Results:Chromatographic resolution permitted reliable quantification in both measurement modes and calibration curves were linear in a range of 150-1000 ng/spot. M. spicata was found to contain significantly higher concentrations of rosmarinic acid. The densitometric quantification allowed the analysis of many samples in a short time with reasonable precision (total precision for Mentha spp extracts, 5.1% and 5.8% for UV and fluorescence detection, respectively). The HPTLC data, allied to assays of linoleic acid peroxidation prevention, suggested the potential of M. spicata (52% Trolox®equivalents) as a natural source for inhibitors of lipid peroxidation.Conclusions:Densitometry can be used for routine determination and quality control of rosmarinic acid in herbal and formulations containing Mentha species.

Algerian mint species: high performance thin layer chromatography quantitative determination of rosmarinic acid and in vitro inhibitory effects on linoleic acid peroxidation

Directory of Open Access Journals (Sweden)

Brahmi Fatiha

2014-12-01

Full Text Available Objective: To determine the quantitative paremeters of rosmarinic acid in Algerian mints, Mentha spicata L. (M. spicata, Mentha pulegium L. and Mentha rotundifolia (L. Huds by high performance thin layer chromatography (HPTLC-densitometric method and screen the effects of these plant extracts on linoleic acid peroxidation. Methods: The analyses were performed on HPTLC silica gel 60 F254 plates with chloroform: acetone: formic acid (75:16.5:8.5, v/v as the mobile phase. Rosmarinic acid was determined in UV at 365 nm and fluorescence at λexc 325 nm with a 550 nm filter, respectively. The effects of plants extracts on linoleic acid peroxidation were measured by an indirect in vitro colorimetric method. Results: Chromatographic resolution permitted reliable quantification in both measurement modes and calibration curves were linear in a range of 150-1 000 ng/spot. M. spicata was found to contain significantly higher concentrations of rosmarinic acid. The densitometric quantification allowed the analysis of many samples in a short time with reasonable precision (total precision for Mentha spp extracts, 5.1% and 5.8% for UV and fluorescence detection, respectively. The HPTLC data, allied to assays of linoleic acid peroxidation prevention, suggested the potential of M. spicata (52% Trolox® equivalents as a natural source for inhibitors of lipid peroxidation. Conclusions: Densitometry can be used for routine determination and quality control of rosmarinic acid in herbal and formulations containing Mentha species.

Novel Eicosapentaenoic Acid-derived F3-isoprostanes as Biomarkers of Lipid Peroxidation*

Science.gov (United States)

Song, Wen-Liang; Paschos, Georgios; Fries, Susanne; Reilly, Muredach P.; Yu, Ying; Rokach, Joshua; Chang, Chih-Tsung; Patel, Pranav; Lawson, John A.; FitzGerald, Garret A.

2009-01-01

Isoprostanes (iPs) are prostaglandin (PG) isomers generated by free radical-catalyzed peroxidation of polyunsaturated fatty acids (PUFAs). Urinary F2-iPs, PGF2α isomers derived from arachidonic acid (AA) are used as indices of lipid peroxidation in vivo. We now report the characterization of two major F3-iPs, 5-epi-8,12-iso-iPF3α-VI and 8,12-iso-iPF3α-VI, derived from the ω-3 fatty acid, eicosapentaenoic acid (EPA). Although the potential therapeutic benefits of EPA receive much attention, a shift toward a diet rich in ω-3 PUFAs may also predispose to enhanced lipid peroxidation. Urinary 5-epi-8,12-iso-iPF3α-VI and 8,12-iso-iPF3α-VI are highly correlated and unaltered by cyclooxygenase inhibition in humans. Fish oil dose-dependently elevates urinary F3-iPs in mice and a shift in dietary ω-3/ω-6 PUFAs is reflected by an increasing slope [m] of the line relating urinary 8, 12-iso-iPF3α-VI and 8,12-iso-iPF2α-VI. Administration of bacterial lipopolysaccharide evokes a reversible increase in both urinary 8,12-iso-iPF3α-VI and 8,12-iso-iPF2α-VI in humans on an ad lib diet. However, while excretion of the iPs is highly correlated (R2 median = 0.8), [m] varies by an order of magnitude, reflecting marked inter-individual variability in the relative peroxidation of ω-3 versus ω-6 substrates. Clustered analysis of F2- and F3-iPs refines assessment of the oxidant stress response to an inflammatory stimulus in vivo by integrating variability in dietary intake of ω-3/ω-6 PUFAs. PMID:19520854

Autoxidation of polyunsaturated fatty acids. Part I. Effect of ozone on the autoxidation of neat methyl linoleate and methyl linolenate

Energy Technology Data Exchange (ETDEWEB)

Pryor, W.A.; Stanley, J.P.; Blair, E.; Cullen, G.B.

Neat samples of polyunsaturated fatty acids were exposed to ozone in air in a flow system, and the formation of peroxides, conjugated dienes and thiobarbituric acid (TBA)-reactive material was followed as a function of time. The effect of ozone is to shorten the induction period normally observed in autoxidation studies, but the ozone, at the concentrations used here (0-1.5 ppm), appears to have no effect on the rates of product formation after the induction period. During the induction period, increasing ozone concentrations gives rise to substantially increased rates of peroxide (or materials which titrate like peroxide) formation, a slightly increased rate of conjugated diene formation, and no significant increase in the rate of production of TBA-reactive material. Vitamin E lengthens the induction period but appears to have no other effect. Some of these data are in conflict with earlier reports of Menzel et al.

UV-induced changes in antioxidant capacities of selected carotenoids toward lecithin in aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Cvetkovic, Dragan [Faculty of Technology, University of Nish, Bulevar oslobodjenja 124, 16000 Leskovac (Serbia); Markovic, Dejan [Faculty of Technology, University of Nish, Bulevar oslobodjenja 124, 16000 Leskovac (Serbia)], E-mail: markovic57@info-net.co.yu

2008-01-15

Antioxidant action of four selected carotenoids (two carotenes, {beta}-carotene and lycopene, and two xanthophylls, lutein and neoxanthin) on UV-induced lecithin lipid peroxidation in aqueous solution has been studied by thiobarbituric acid (TBA) test. TBA test is based on absorbance measurements of complex formed between malondialdehyde, secondary product of lipid peroxidation and thiobarbituric acid, at 532 nm. The antioxidant capacities of investigated carotenoids appeared to be strongly affected by UV-action. High energy input of the involved UV-photons plays major governing role, though a certain impact of the carotenoid structures cannot be neglected. The results suggest a minor remained contribution of selected carotenoids to prevention of lecithin peroxidation in the studied system as a result of UV-irradiation.

UV-induced changes in antioxidant capacities of selected carotenoids toward lecithin in aqueous solution

Science.gov (United States)

Cvetkovic, Dragan; Markovic, Dejan

2008-01-01

Antioxidant action of four selected carotenoids (two carotenes, β-carotene and lycopene, and two xanthophylls, lutein and neoxanthin) on UV-induced lecithin lipid peroxidation in aqueous solution has been studied by thiobarbituric acid (TBA) test. TBA test is based on absorbance measurements of complex formed between malondialdehyde, secondary product of lipid peroxidation and thiobarbituric acid, at 532 nm. The antioxidant capacities of investigated carotenoids appeared to be strongly affected by UV-action. High energy input of the involved UV-photons plays major governing role, though a certain impact of the carotenoid structures cannot be neglected. The results suggest a minor remained contribution of selected carotenoids to prevention of lecithin peroxidation in the studied system as a result of UV-irradiation.

UV-induced changes in antioxidant capacities of selected carotenoids toward lecithin in aqueous solution

International Nuclear Information System (INIS)

Cvetkovic, Dragan; Markovic, Dejan

2008-01-01

Antioxidant action of four selected carotenoids (two carotenes, β-carotene and lycopene, and two xanthophylls, lutein and neoxanthin) on UV-induced lecithin lipid peroxidation in aqueous solution has been studied by thiobarbituric acid (TBA) test. TBA test is based on absorbance measurements of complex formed between malondialdehyde, secondary product of lipid peroxidation and thiobarbituric acid, at 532 nm. The antioxidant capacities of investigated carotenoids appeared to be strongly affected by UV-action. High energy input of the involved UV-photons plays major governing role, though a certain impact of the carotenoid structures cannot be neglected. The results suggest a minor remained contribution of selected carotenoids to prevention of lecithin peroxidation in the studied system as a result of UV-irradiation

Morpho- Physiological Changes of Hempseed (Cannabis sativa L. Traits as Affected by Seed Priming with Folic Acid and Hydrogen Peroxide

Directory of Open Access Journals (Sweden)

Shirin Karbalaye Golizadeh

2016-03-01

Full Text Available To evaluate the effects of seed priming of hempseed with folic acid and hydrogen peroxide on some morphological and physiological traits a factorial greenhouse experiment based on randomized complete design with four replications was conducted at Islamic Azad University, Mahabad Branch. Treatments consisted of hydrogen peroxide at five levels (0, 7.5, 15, 22.5, 30 mm/liter as the first factor and the four leveld of folic acid (5, 10, 20, 27 mm/liter as the second factor.Seeds, to be primed, were immersed into solution of folic acid for 24 hours and hydrogen peroxide for 6 hours. The characteristics like chlorophyll a, chlorophyll b, total chlorophyll content, relative water content, plant height, root length, allometric coefficient, plant fresh and dry weights, were measured. Result of analysis of variance showed that the effects of folic acid and hydrogen peroxide on all characters were significant, but the interaction between the two treatments were only significant on relative water content and allometric coefficient. In this study, seed priming with 15 mm/liter of hydrogen peroxide and 5mm folic acid resulted in highest chlorophyll a, chlorophyll b, total chlorophyll contents, plant height, root length, fresh and dry weights. Increasing hydrogen peroxide level above 15mm/liter affected traits negatively. Combinated treatments of 15 mm/liter of hydrogen peroxide and 5 and 10 mm of folic acid resulted in highest relative water content and allometric coefficient, respectively. Based on the results obtained it can be concluded that priming seeds with 15 mm/liter of hydrogen peroxide and 5mm folic acid is recommended to produce proper morphological and physiological traits.

Lipid Peroxidation and Antioxidant Status in Preeclampsia

Directory of Open Access Journals (Sweden)

Rokeya Begum

2011-07-01

Full Text Available Background: Preeclampsia is the most common and major medical complication of pregnancy with a high incidence of maternal and foetal morbidity and mortality. During pregnancy abnormally increased lipid peroxidation and free radical formation as well as significantly decreased antioxidants production in maternal blood may lead to pathogenesis of preeclampsia. So, we designed this study as little information is known about lipid peroxidation and antioxidant level in preeclampsia. Objectives: To assess the serum malondialdehyde (MDA level as a lipid peroxidation product and vitamin E (antioxidant level in women with preeclampsia as well as in normal pregnancy and to compare the values. Materials and Methods: The study was conducted on 60 women aged from 25 to 35 years in the department of Biochemistry, Budi Kemuliaan Maternity Hospital (BKMH in Jakarta during the period April to July 2004. Twenty were normal pregnant women and 20 were preeclamptic patients. For comparison age matched 20 apparently healthy nonpregnant women were included in the study. The study subjects were selected from outpatient department (OPD of Obstetrics and Gynaecology of BKMH in Jakarta. Serum MDA (lipid peroxidation product level was measured by thiobarbituric acid reactive substances assay (TBRAS method and vitamin E was estimated spectroflurometrically. Data were analyzed by unpaired Student’s t test between the groups by using SPSS version 12. Results: The mean serum MDA levels were significantly higher in normal pregnancy and also in preeclampsia than that of nonpregnant control group women (p<0.001. Again the serum MDA levels were significantly higher in preeclampsia than that of normal pregnant women (p<0.001. The serum vitamin E levels were significantly lower in preeclampsia and also in normal pregnancy than that of nonpregnant control women (p<0.001. Moreover, the serum vitamin E levels were significantly lower in preeclampsia compared to that of normal

Synergism between hydrogen peroxide and seventeen acids against five agri-food-borne fungi and one yeast strain.

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Martin, H; Maris, P

2012-12-01

The objective of this study was to evaluate fungicidal efficacy of hydrogen peroxide administered in combination with 17 mineral and organic acids authorized for use in the food industry. The assays were performed on a 96-well microplate using a microdilution technique based on the checkerboard titration method. The six selected strains (one yeast and five fungi) were reference strains and strains representative of contaminating fungi found in the food industry. Each synergistic hydrogen peroxide/acid combination found after fifteen minutes contact time at 20 °C in distilled water was then tested in conditions simulating four different use conditions. Twelve combinations were synergistic in distilled water, eleven of these remained synergistic with one or more of the four mineral and organic interfering substances selected. Hydrogen peroxide/formic acid combination remained effective against four strains and was never antagonistic against the other two fungi. Combinations with propionic acid and acetic acid stayed synergistic against two strains. Those with oxalic acid and lactic acid kept their synergism only against Candida albicans. No synergism was detected against Penicillium cyclopium. Synergistic combinations of disinfectants were revealed, among them the promising hydrogen peroxide/formic acid combination. A rapid screening method developed in our laboratory for bacteria was adapted to fungi and used to reveal the synergistic potential of disinfectants and/or sanitizers combinations. © 2012 The Society for Applied Microbiology.

Muscle Thiobarbituric Acid Reactive Substance of the Atlantic Herring (Clupea harengus in Marinades Collected in the Market Network

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Alena Halamíčková

2010-01-01

Full Text Available Fish fat belongs to highly specific nutritious elements especially due to its high content of polyunsaturated fatty acids. The aim of the present study was to determine the content of 2-thiobarbituric acid reactive substances in over-the-counter cold and warm marinades in which the base fish material consists of the Atlantic herring (Clupea harengus. Fifty six marinated fish products stored at refrigeration temperatures were analyzed before their expiration date. Their fat content was determined by means of the Soxhlet method and the TBARS validated fluorimetric micromethod. Lowest TBARS values were characteristic of warm baked marinades (1.17 ± 0.40 mg MDA/ kg muscle and in case of cold marinades for the rolled herring fillets with pepper (5.03 ± 0.54 mg MDA/kg muscle whereas the highest TBARS values were observed in warm cooked marinades (16.48 ± 4.22 mg MDA/kg muscle and in roll mops sold over the counter (7.61 ± 3.87 mg MDA/kg muscle. The results showed that fat content is not always critical for herring TBARS determination in marinades. For the consumer safety it is essential to pay attention to cold marinades in brine sold over the counter and baked marinades in aspic before their expiration date.

EFFECT OF PHYSICAL EXERCISE ON LIPID PEROXIDATION AND ANTIOXIDANT ASCORBIC ACID DEFENSE

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Ljiljana M. Popović

2006-06-01

Full Text Available Strenuous exercises greatly increase oxygen consumption in the whole body, especially in skeletal muscles. Large part of oxygen consumption is reduced to H2O and ATP, but smaller part (2-5% results in an increased leakage of electrons from the mitochondrial respiratory chain, forming various reactive oxygen species ─ ROS (O2˙¯, H2O2 i OH˙. These free radicals are capable of triggering a chain of damaging biochemical and physiological reactions (oxidative stress, lipid peroxidation,as a base for skeletal muscles damage after exercise. MDA (malondialdehide is a marker of exercise induced lipid peroxidation process. L–ascorbic acid is a major aqueous-phase antioxidant. To estimate antioxidant role of ascorbic acid we use rate between dehidroascorbate and ascorbate. In this paper those markers were determinated in 30 students, in rest and after treadmill running protocol (Bruce Treadmill Protocol. It was found that after the treadmill test , plasma MDA level had increased from 3,04 to 4,39 μM/L. Plasma ascorbic acid was also found to be higher after the treadmill test comparing to rest level (from 55,4 to 67,6 μM/L. DHA/A level in rest was 1,62 and after treadmill test it increased to 2,05. These results suggests that strenuous exercise increased process of lipid peroxidation, but in the same time increased ascorbic acid level in plasma and DHA/A rate indicates stronger antioxidant defense system.

Lipid peroxidation in neonatal mouse brain subjected to two different types of hypoxia.

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Hasegawa, K; Yoshioka, H; Sawada, T; Nishikawa, H

1991-01-01

To elucidate the role of free radicals in the pathogenesis of neonatal hypoxic encephalopathy, we determined the content of thiobarbituric acid reactants (TBARs), as an index of lipid peroxidation related with a free radical reaction, in the brains of newborn mice during hypoxia and recovery from hypoxia. Hypoxic stress was induced by 100% nitrogen gas breathing (N2 group) or 100% carbon dioxide gas breathing (CO2 group). TBARs increased with 20 minutes of hypoxia and returned to the control level during the recovery period in both groups. The increase in TBARs in the CO2 group was greater than that in the N2 group. These results may suggest that free radical reaction occurs during the hypoxic period and that CO2 hypoxia is more effective on free radical production in the newborn brain than N2 hypoxia.

Formation of malonic dialdehyde and other 2-thiobarbituric-acid-active products in γ-radiolysis of DNA and DNA model substances in aqueous solution

International Nuclear Information System (INIS)

Langfinger, K.D.

1984-01-01

During radiation-induced DNA strand break, a product was observed which reacts positively with 2-thiobarbituric acid (TBA) to malonic dialdehyde (MDA) but is not a free MDA. The paper therefore discusses the formation of products during γ irradiation of DNA and DNA model substances which react positively with TBA to MDA. This reaction is highly sensitive but has low specificity, so that further analytical techniques were used for characterisation. These were: kinematic studies on chromophore formation using TBA, UV spectroscopy, and chromatography. The investigations comprised 1. Irradiation of sugars and polyalcohols. 2. Irradiation of nucleosides and nucleotides. 3. Irradiation of DNA. (orig./PW) [de

[Inhibition of Linseed Oil Autooxidation by Essential Oils and Extracts from Spice Plants].

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Misharina, T A; Alinkina, E S; Terenina, M B; Krikunova, N I; Kiseleva, V I; Medvedeva, I B; Semenova, M G

2015-01-01

Clove bud essential oil, extracts from ginger, pimento and black pepper, or ascorbyl palmytate were studied as natural antioxidants for the inhibition of autooxidation of polyunsaturated fatty acids in linseed oil. Different methods were used to estimate antioxidant efficiency. These methods are based on the following parameters: peroxide values; peroxide concentration; content of degradation products of unsaturated fatty acid peroxides, which acted with thiobarbituric acid; diene conjugate content; the content of volatile compounds that formed as products of unsaturated fatty acid peroxide degradation; and the composition of methyl esters of fatty acids in samples of oxidized linseed oil.

Urea application promotes amino acid metabolism and membrane lipid peroxidation in Azolla.

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Chen, Jiana; Huang, Min; Cao, Fangbo; Pardha-Saradhi, P; Zou, Yingbin

2017-01-01

A pot experiment was conducted to evaluate the effect of urea on nitrogen metabolism and membrane lipid peroxidation in Azolla pinnata. Compared to controls, the application of urea to A. pinnata resulted in a 44% decrease in nitrogenase activity, no significant change in glutamine synthetase activity, 660% higher glutamic-pyruvic transaminase, 39% increase in free amino acid levels, 22% increase in malondialdehyde levels, 21% increase in Na+/K+- levels, 16% increase in Ca2+/Mg2+-ATPase levels, and 11% decrease in superoxide dismutase activity. In terms of H2O2 detoxifying enzymes, peroxidase activity did not change and catalase activity increased by 64% in urea-treated A. pinnata. These findings suggest that urea application promotes amino acid metabolism and membrane lipid peroxidation in A. pinnata.

Evaluation of human dental loss caused by carbamide peroxide bleacher compared with phosphoric acid conditioning - radioactive method

International Nuclear Information System (INIS)

Adachi, Eduardo Makoto; Yousseff, Michel Nicolau; Saiki, Mitiko

2002-01-01

The radiometric method was applied to the evaluation of dental loss caused by carbamide peroxide when it is applied on the surface layers of enamel and dentin tissues. Also the dental loss caused by the etching with 37% phosphoric acid procedure used in aesthetic restoration was assessed for comparison with those results obtained. The tooth samples irradiated with a P standard in a thermal neutron flux of the nuclear reactor were placed in contact with 10% carbamide peroxide or with 37% phosphoric acid solution. The radioactivity of 32 P transferred from the radioactive teeth to the bleaching gel or to etching acid was measured using a Geiger Muller detector to calculate the mass of P removed in this treatment and losses were calculated after obtaining their P concentrations. Results obtained indicated that enamel and dentin exposed to carbamide peroxide bleaching agent lose phosphorus. The extent of enamel loss was smaller than that obtained for dentin. In the case of acid etching, there was no difference between the results obtained for enamel and dentin loss. Also the dentin loss obtained after a treatment of 30 applications of 10% carbamide peroxide was the same magnitude of that one application of 37% phosphoric acid. (author)

Urea application promotes amino acid metabolism and membrane lipid peroxidation in Azolla.

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Jiana Chen

Full Text Available A pot experiment was conducted to evaluate the effect of urea on nitrogen metabolism and membrane lipid peroxidation in Azolla pinnata. Compared to controls, the application of urea to A. pinnata resulted in a 44% decrease in nitrogenase activity, no significant change in glutamine synthetase activity, 660% higher glutamic-pyruvic transaminase, 39% increase in free amino acid levels, 22% increase in malondialdehyde levels, 21% increase in Na+/K+- levels, 16% increase in Ca2+/Mg2+-ATPase levels, and 11% decrease in superoxide dismutase activity. In terms of H2O2 detoxifying enzymes, peroxidase activity did not change and catalase activity increased by 64% in urea-treated A. pinnata. These findings suggest that urea application promotes amino acid metabolism and membrane lipid peroxidation in A. pinnata.

Comparative evaluation of retinoic acid, benzoyl peroxide and erythromycin lotion in acne vulgarils

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Dogra A

1993-01-01

Full Text Available Ninety three patients suffering from acne vulgaris were treated with 0.05% retinoic acid (23 patients, 10% benzyoyl peroxide (24 patients, 2% erythromycin lotin (25 patients and 50% glycerine in methylated spirit (21 patients used as a control, for a period of 6 weeks. The patients were evaluated at 2 weeks and 6 weeks by spot counting of the lesions and diagrammatic representations. Good to excellent results were obtained in 69.6% of patients of erythromycin lotion. Retinoic acid was more effective in reducing noninflammatory lesions (75.2% whereas inflammatory lesions showed better response (73.6% with erythromycin lotion and benzoyl peroxide was almost equally effective in both types of lesions.

Reinvestigation of the Henry's law constant for hydrogen peroxide with temperature and acidity variation.

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Huang, Daoming; Chen, Zhongming

2010-01-01

Hydrogen peroxide is not only an important oxidant in itself; it also serves as both sink and temporary reservoir for other important oxidants including HOx (OH and HO2) radicals and O3 in the atmosphere. Its partitioning between gas and aqueous phases in the atmosphere, usually described by its Henry's law constant (K(H)), significantly influences its role in atmospheric processes. Large discrepancies between the K(H) values reported in previous work, however, have created uncertainty for atmospheric modelers. Based on our newly developed online instrumentation, we have re-determined the temperature and acidity dependence of K(H) for hydrogen peroxide at an air pressure of (0.960 +/- 0.013) atm (1 atm = 1.01325 x 10(5) Pa). The results indicated that the temperature dependence of K(H) for hydrogen peroxide fits to the Van't Hoff equation form, expressed as lnK(H) = a/T - b, and a = -deltaH/R, where K(H) is in M/atm (M is mol/L), T is in degrees Kelvin, R is the ideal gas constant, and deltaH is the standard heat of solution. For acidity dependence, results demonstrated that the K(H) value of hydrogen peroxide appeared to have no obvious dependence on decreasing pH level (from pH 7 to pH 1). Combining the dependence of both temperature and acidity, the obtained a and b were 7024 +/- 138 and 11.97 +/- 0.48, respectively, deltaH was (58.40 +/- 1.15) kJ/(K x mol), and the uncertainties represent sigma. Our determined K(H) values for hydrogen peroxide will therefore be of great use in atmospheric models.

Nuts as raw material for confectionary industry

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L. Eliseeva

2017-03-01

Full Text Available The aim of this paper was to explore chemical and sensory stability of walnuts during their storage. We determined fatty acids composition, as well as chemical indicators of lipid oxidative stability (peroxide and thiobarbituric values and conjugated dienes during accelerated storage of walnuts. Besides this, a thorough descriptive analysis was performed. The accelerated storage of walnuts was shown to cause the significant changes in sensory characteristics of walnuts, as well as the significant increase of peroxide and thiobarbituric values and contents of conjugated dienes.

COMPARATIVE STUDY OF ANTIBACTERIAL ACTIVITY OF PEROXYDISUCCINIC ACID, HYDROGEN PEROXIDE AND THEIR MIXTURE

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Blazheyevskiy M.Ye.,

2016-06-01

Full Text Available Introduction. It is known that reactive oxygen species (ROS generated in vivo by cell aerobic metabolism cause multiple damage in different cell organelles and kill not only obligate anaerobes and microaerophilles, but also aerobes. ROS generated by phagocytes and representatives of normal microflora are an important component of macroorganism defense from most pathogens, which is explained by their ability to damage different biological structures. ROS have high reactivity and let us use them in vitro as effective biocides. Hydrogen peroxide is widely used in many industries, in particular, in medicine and veterinary as antiseptic and disinfectant agent due to its safety for environment and broad spectrum of antimicrobial activity including spore-forming bacteria. However, in the recent years certain decrease of background sensitivity of microorganisms to hydrogen peroxide and occurrence of resistant strains of pathogenic microorganisms to this agent has been noted. The aim of this work is to carry out a comparative study of antimicrobial activity of hydrogen peroxide, peroxydisuccinic acid (PDSA, monoperoxysuccinic acid (MPSA, and mixture of PDSA and hydrogen peroxide (Н2О2. Materials and methods. The substances of peroxydisuccinic acid (PDSA and monoperoxysuccinic acid (MPSA were prepared by well known methods. The following test-strains were used to assess antimicrobial activity of the agents: Staphylococcus aureus АТСС 25923, Escherichia coli АТСС 25922, Pseudomonas aeruginosa АТСС 27853, Pseudomonas aeruginosa АТСС 9027, Basillus сereus АТСС 10702, Basillus сereus АТСС 96, Basillus subtilis АТСС 6633, Proteus vulgaris ATCC 4636, Candida albicans АТСС 885/653, and Candida albicans АТСС 10231. All disinfectant agents were diluted in distilled water at 40 ºС and stirred. The microbial burden was 2∙109 CFU/ml of the medium, and for kinetic studies 105 CFU/ml of the medium, it was standardizing

Determination of amino acid and protein peroxides by the xylenol orange-Fe(III) complex

International Nuclear Information System (INIS)

Collins, J.; Craig, G.; Gebicki, J.

1996-01-01

Oxidative stress imposed on living organisms is believed to lead to the depletion of their antioxidant defences, followed by chemical changes in the cell constituents. These may ultimately develop into pathological conditions such as cancer or cardiovascular disease. An assay of peroxides which could be applied to tissues or simple tissue extracts would prove extremely useful in the studies of the phenomenon of oxidative stress. With this purpose, the authors have tested the ability of two peroxide assay techniques to measure the formation of amino acid and protein peroxides in aqueous solutions irradiated with gamma rays, using a modification of the method based on the oxidation of Fe(II)) by peroxides and complexing of the Fe(III) produced by xylenol orange. The molar extinction coefficients of the peroxides tested were determined by comparison with the well-tested iodometric assay. This work was extended to the detection of all organic peroxides in human blood plasma or serum subjected to oxidative stress, where the iodometric assay proved difficult to apply and unreliable because of the binding of iodine to the blood components. Preliminary results suggest that exposure of serum to gamma radiation leads to immediate peroxidation of the proteins, with a delay before generation of lipid peroxides

The effects of therapeutic concentrations ofamisulpride andrisperidone on human plasma lipid peroxidation – invitro studies

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Anna Dietrich-Muszalska

2011-09-01

Full Text Available Introduction: Antipsychotics may in different ways affect the oxidative stress measured by plasma lipid peroxidation. Probably some of them may intensify the oxidative balance disturbances occurring in schizophrenia. The effects of amisulpride and risperidone on redox processes are not known sufficiently yet. Aim of the study: Establishment of the effects of amisulpride and risperidone on human plasma lipid peroxidation measured by determination of the level of thiobarbituric acid-reactive substances (TBARS, in vitro. Material and methods: Blood for the studies was collected from healthy volunteers (aged 24-26 years for ACD solution. Active substances of the examined drugs were dissolved in 0.01% dimethylsulfoxide (DMSO to the final concentrations (of amisulpride 578 ng/ml and risperidone 64 ng/ml and incubated with plasma for 1 and 24 hours at 37ºC. For each experiment the control samples of plasma with DMSO (without the drug were performed. The lipid peroxidation level was measured in plasma by determining the TBARS concentration, using the spectrophotometric method (acc. to Rice-Evans, 1991. The results were analysed using the following statistical methods: the paired Student t-test and ANOVA II variance analysis and NIR test (StatSoft Inc., Statistica v. 6.0. Results: The ANOVA II variance analysis indicated significant differences in the effects of both drugs on TBARS level (F=4.26; df=2, p0.05. Conclusion: Amisulpride and risperidone in concentrations corresponding to doses recommended for treatment of acute episode of schizophrenia do not induce oxidative stress measured by lipid peroxidation. Unlike risperidone, amisulpride exhibits antioxidative effects.

Promotion of radiation peroxidation in models of lipid membranes by caesium and rubidium counter-ions: micellar linolenic acids

Energy Technology Data Exchange (ETDEWEB)

Raleigh, J A; Kremers, W [Atomic Energy of Canada Ltd., Pinawa, Manitoba. Whiteshell Nuclear Research Establishment

1978-11-01

Caesium and rubidium counter-ions increase peroxidation in irradiated micelles of linoleic (18 : 2) and linolenic (18 :3) acids. The effect was specific to Cs/sup +/ and Rb/sup +/ in the alkali metal series. The effect was independent of the salts used (Cl/sup -/, NO/sub 3//sup -/, Cl0/sub 4//sup -/) and, therefore, independent of the chaotropic nature, and reactivity with hydroxyl radicals of Cl/sup -/, NO/sub 3//sup -/ and ClO/sub 4//sup -/. The promotion of peroxidation by Cs/sup +/ and Rb/sup +/ is interpreted in terms of their effect on fatty acid micelle structure. The dependence of radiation peroxidation on lipid structure in the micelles may be significant for studies of peroxidation in highly structured cell membranes.

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

International Nuclear Information System (INIS)

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

1983-01-01

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

Effect of soy sauce on lipid oxidation of irradiated pork patties

International Nuclear Information System (INIS)

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

2013-01-01

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

Investigation of Influential Parameters in Deep Oxidative Desulfurization of Dibenzothiophene with Hydrogen Peroxide and Formic Acid

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Alireza Haghighat Mamaghani

2013-01-01

Full Text Available An effective oxidative system consisting of hydrogen peroxide, formic acid, and sulfuric acid followed by an extractive stage were implemented to remove dibenzothiophene in the simulated fuel oil. The results revealed such a great performance in the case of H2O2 in the presence of formic and sulfuric acids that led to the removal of sulfur compounds. Sulfuric acid was employed to increase the acidity of media as well as catalytic activity together with formic acid. The oxidation reaction was followed by a liquid-liquid extraction stage using acetonitrile as a polar solvent to remove produced sulfones from the model fuel. The impact of operating parameters including the molar ratio of formic acid to sulfur (, hydrogen peroxide to sulfur (, and the time of reaction was investigated using Box-Behnken experimental design for oxidation of the model fuel. A significant quadratic model was introduced for the sulfur removal as a function of effective parameters by the statistic analysis.

Lipoprotein profiles and serum peroxide levels of aged women consuming palmolein or oleic acid-rich sunflower oil diets.

Science.gov (United States)

Cuesta, C; Ródenas, S; Merinero, M C; Rodríguez-Gil, S; Sánchez-Muniz, F J

1998-09-01

To investigate the hypercholesterolemic effects of a dietary exchange between 16:0 and 18:1 while 18:2 was at relatively lower level (approximately 4%) in aged women with initially high total serum cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) values and with high intakes of dietary cholesterol. Subjects were assigned to two consecutive 28 d periods. In the first period all subjects followed an oleic acid-rich diet in the form of oleic acid-rich sunflower oil. This was followed by a second period rich in palmitic acid in the form of palmolein. Nutrient intakes, serum lipids, lipoproteins, antioxidant vitamins, peroxides and LDL-peroxides were measured at two dietary periods. Instituto de Nutrición y Bromatología (CSIC), Departamento de Nutrición y Bromatología I (Nutrición) and Sección Departamental de Quimica Analítica, Universidad Complutense, Madrid, Spain. The palmolein period led to an increase in TC (P or = 6.21 mmol/L or with TC 6.21 mmol/L than in women with TC < 6.21 mmol/L, but palmolein decreased serum and LDL-peroxide in hypercholesterolemics more than in the normocholesterolemics, resulting in serum and LDL-peroxide levels which theoretically are more adequate. Though palmolein increased LDL-C concentrations, it better protected LDL particles, mainly in women with high TC, against peroxidation than did oleic acid-rich sunflower oil.

Suitability of hyperspectral imaging for rapid evaluation of thiobarbituric acid (TBA) value in grass carp (Ctenopharyngodon idella) fillet.

Science.gov (United States)

Cheng, Jun-Hu; Sun, Da-Wen; Pu, Hong-Bin; Wang, Qi-Jun; Chen, Yu-Nan

2015-03-15

The suitability of hyperspectral imaging technique (400-1000 nm) was investigated to determine the thiobarbituric acid (TBA) value for monitoring lipid oxidation in fish fillets during cold storage at 4°C for 0, 2, 5, and 8 days. The PLSR calibration model was established with full spectral region between the spectral data extracted from the hyperspectral images and the reference TBA values and showed good performance for predicting TBA value with determination coefficients (R(2)P) of 0.8325 and root-mean-square errors of prediction (RMSEP) of 0.1172 mg MDA/kg flesh. Two simplified PLSR and MLR models were built and compared using the selected ten most important wavelengths. The optimised MLR model yielded satisfactory results with R(2)P of 0.8395 and RMSEP of 0.1147 mg MDA/kg flesh, which was used to visualise the TBA values distribution in fish fillets. The whole results confirmed that using hyperspectral imaging technique as a rapid and non-destructive tool is suitable for the determination of TBA values for monitoring lipid oxidation and evaluation of fish freshness. Copyright © 2014 Elsevier Ltd. All rights reserved.

Inhibition of Lipid Peroxidation by Enzymatic Hydrolysates from Wheat Bran

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Yanping Cao

2011-01-01

Full Text Available Wheat bran, an important by-product of the cereal industry, is rich in potentially health-promoting phenolic compounds. The phenolics are mainly esterified to the cell wall polysaccharides. In our previous paper, wheat bran was destarched and deproteinated by α-amylase, protease and amyloglucosidase successively and further hydrolyzed using Bacillus subtilis xylanases, and the enzymatic hydrolysates from wheat bran (EHWB showed good scavenging activity in vitro. The aim of this study is to further characterize the antioxidant potential of EHWB against various systems, both ex vivo and in vivo, namely, rat liver microsomal lipid peroxidation systems induced by Fe2+/H2O2 and Fe3+-adenosine diphosphate (ADP/dihydronicotinamide adenine dinucleotide phosphate (NADPH, copper- and 2,2’-azo-bis(2-amidinopropane dihydrochloride (AAPH-induced human low-density lipoprotein (LDL oxidation systems, and alloxan-induced in vivo lipid peroxidation in mice. EHWB inhibited lipid peroxidation in rat liver microsomes induced by Fe2+/H2O2 and Fe3+-ADP/NADPH in a concentration-dependent manner with 90.3 and 87 % inhibition of lipid peroxidation at 50 mg/L, respectively, which were similar to that of butylated hydroxytoluene (BHT at 20 mg/L. The antioxidant potential of EHWB at a concentration ranging from 10 to 20 mg/L in the nonenzymatic system was more effective than in the enzymatic system. EHWB strongly inhibited in vitro copper- and AAPH-mediated oxidation of LDL in a concentration- and time-dependent manner with 52.41 and 63.03 % inhibition at 20 mg/L, respectively, which were similar to that of ascorbate at 10 mg/L. EHWB significantly decreased the level of thiobarbituric acid reactive substances (TBARS and increased the activities of glutathione peroxidase (GSH-Px, catalase (CAT and superoxide dismutase (SOD in serum and liver of alloxan-treated mice compared with the control. These results demonstrated that EHWB might be efficient in the protection of

The Effects of Subacute Exposure of Peracetic Acid on Lipid Peroxidation and Hepatic Enzymes in Wistar Rats

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Abdoljalal Marjani

2010-10-01

Full Text Available Objectives: This study was undertaken to determine the effect of subacute exposure of peracetic acid on lipid peroxidation and hepatic enzymes in Wistar rats.Methods: 48 male animals in Treatment Group I, II and III received 0.2%, 2% and 20% peracetic acid daily for 2 and 4 weeks.Results: Serum malondialdehyde increased and Alanine Transaminase and Aspartate Transaminase decreased significantly in groups 2 and 3, compared to the control group. The malondialdehyde, Alanine Transaminase and Aspartate Transaminase with 0.2% and 2% doses of peracetic acid for 2 weeks do not lead to the alteration of malondialdehyde and enzyme activities.Conclusion: This study demonstrated that the enhancement of malondialdehyde could provide an oxidative damage induced by disinfectant peroxidation at 20% and 2% doses at 2 and 4 weeks. The consumption of peroxidation with 20% for 2 weeks and 2% for 4 weeks can cause the increase of malondialdehyde and the decrease of enzyme activities, respectively.

The Effects of Subacute Exposure of Peracetic Acid on Lipid Peroxidation and Hepatic Enzymes in Wistar Rats

Science.gov (United States)

Marjani, Abdoljalal; Golalipour, Mohammad J.; Gharravi, Anneh M.

2010-01-01

Objectives This study was undertaken to determine the effect of subacute exposure of peracetic acid on lipid peroxidation and hepatic enzymes in Wistar rats. Methods 48 male animals in Treatment Group I, II and III received 0.2%, 2% and 20% peracetic acid daily for 2 and 4 weeks. Results Serum malondialdehyde increased and Alanine Transaminase and Aspartate Transaminase decreased significantly in groups 2 and 3, compared to the control group. The malondialdehyde, Alanine Transaminase and Aspartate Transaminase with 0.2% and 2% doses of peracetic acid for 2 weeks do not lead to the alteration of malondialdehyde and enzyme activities. Conclusion This study demonstrated that the enhancement of malondialdehyde could provide an oxidative damage induced by disinfectant peroxidation at 20% and 2% doses at 2 and 4 weeks. The consumption of peroxidation with 20% for 2 weeks and 2% for 4 weeks can cause the increase of malondialdehyde and the decrease of enzyme activities, respectively. PMID:22043353

The effect of delignification process with alkaline peroxide on lactic acid production from furfural residues

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Yong Tang

2012-11-01

Full Text Available Furfural residues produced from the furfural industry were investigated as a substrate for lactic acid production by simultaneous saccharification and fermentation (SSF. Alkaline peroxide was used for delignification of furfural residues to improve the final lactic acid concentration. The residue was treated with 1.3% to 1.7% hydrogen peroxide at 80 °C for 1 h with a substrate concentration of 3.33%. SSF of furfural residues with different delignification degrees were carried out to evaluate the effect of delignification degree on lactic acid production. Using corn hydrolysates/ furfural residues as substrates, SSF with different media were carried out to investigate the effect of lignin on the interaction between enzymes and lactic acid bacteria. Lactic acid bacteria had a negative effect on cellulase, thus resulting in the reduction of enzyme activity. Lignin and nutrients slowed down the decreasing trend of enzyme activity. A higher delignification resulted in a slower fermentation rate and lower yield due to degradation products of lignin and the effect of lignin on the interaction between enzymes and lactic acid bacteria. For the purpose of lactic acid production, a moderate delignification (furfural residues with the lignin content of 14.8% was optimum.

High pressure direct synthesis of adipic acid from cyclohexene and hydrogen peroxide via capillary microreactors

NARCIS (Netherlands)

Shang, M.; Noël, T.; Su, Y.; Hessel, V.

2016-01-01

The direct synthesis of adipic acid from hydrogen peroxide and cyclohexene was investigated in capillary microreactors at high temperature (up to 115°C ) and pressure (up to 70 bar). High temperature was already applied in micro-flow packed-bed reactors for the direct adipic acid synthesis. In our

Quantitative Structure-Activity Relationships Predicting the Antioxidant Potency of 17β-Estradiol-Related Polycyclic Phenols to Inhibit Lipid Peroxidation

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Katalin Prokai-Tatrai

2013-01-01

Full Text Available The antioxidant potency of 17β-estradiol and related polycyclic phenols has been well established. This property is an important component of the complex events by which these types of agents are capable to protect neurons against the detrimental consequences of oxidative stress. In order to relate their molecular structure and properties with their capacity to inhibit lipid peroxidation, a marker of oxidative stress, quantitative structure-activity relationship (QSAR studies were conducted. The inhibition of Fe3+-induced lipid peroxidation in rat brain homogenate, measured through an assay detecting thiobarbituric acid reactive substances for about seventy compounds were correlated with various molecular descriptors. We found that lipophilicity (modeled by the logarithm of the n-octanol/water partition coefficient, logP was the property that influenced most profoundly the potency of these compounds to inhibit lipid peroxidation in the biological medium studied. Additionally, the important contribution of the bond dissociation enthalpy of the phenolic O-H group, a shape index, the solvent-accessible surface area and the energy required to remove an electron from the highest occupied molecular orbital were also confirmed. Several QSAR equations were validated as potentially useful exploratory tools for identifying or designing novel phenolic antioxidants incorporating the structural backbone of 17β-estradiol to assist therapy development against oxidative stress-associated neurodegeneration.

Serum levels of brain-derived neurotrophic factor and thiobarbituric acid reactive substances in chronically medicated schizophrenic patients: a positive correlation Níveis séricos do fator neurotrófico derivado do cérebro e dos produtos de reação com o ácido tiobarbitúrico em pacientes com esquizofrenia cronicamente medicados: correlação positiva

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Clarissa Severino Gama

2008-12-01

Full Text Available OBJECTIVE: The neurotrophins, antioxidant enzymes and oxidative markers have reciprocal interactions. This report verified in chronically stable medicated schizophrenic patients whether there are correlations between the serum levels of superoxide dismutase, a key enzyme in the antioxidant defense, thiobarbituric acid reactive substances, a direct index of lipid peroxidation, and brain-derived neurotrophic factor, the most widely distributed neurotrophin. METHOD: Sixty DSM-IV schizophrenic patients were included (43 males, 17 females. Mean age was 34.7 ± 10.8 years, mean age at first episode was 19.8 ± 7.9 years, and mean illness duration was 14.9 ± 8.5 years. Each subject had a blood sample collected for the determination of serum levels of brain-derived neurotrophic factor, thiobarbituric acid reactive substances and superoxide dismutase. RESULTS: Brain-derived neurotrophic factor levels showed a positive correlation with thiobarbituric acid reactive substances levels (r = 0.333, p = 0.009. Brain-derived neurotrophic factor levels were not correlated with superoxide dismutase levels (r = - 0.181, p = 0.166, and superoxide dismutase levels were not correlated with thiobarbituric acid reactive substances levels (r = 0.141, p = 0.284. CONCLUSIONS: The positive correlation between brain-derived neurotrophic factor and thiobarbituric acid reactive substances suggests the need of further investigation on intracellular interactions of neurotrophins, antioxidant enzymes and oxidative markers. In addition, this opens a venue for investigation on treatments for the prevention of neurotoxicity along the course of schizophrenia.OBJETIVO: As neurotrofinas, enzimas antioxidantes e marcadores de oxidação têm interações. Este estudo verificou se existem correlações entre os níveis séricos de superóxido-dismutase, uma enzima chave na defesa antioxidante, os produtos de reação com o ácido tiobarbitúrico, um indicador direto de peroxidação lip

Disinfection of wastewater by hydrogen peroxide or peracetic acid: development of procedures for measurement of residual disinfectant and application to a physicochemically treated municipal effluent.

Science.gov (United States)

Wagner, Monika; Brumelis, Daina; Gehr, Ronald

2002-01-01

The Montreal Urban Community Wastewater Treatment Plant (MUCWTP) located in Montreal. Quebec, Canada, uses physicochemical treatment processes prior to discharging wastewater into the St. Lawrence River via an outfall tunnel of 2 hours retention time. Although chlorination facilities exist, they are not being used, and the MUCWTP is seeking alternative methods for disinfection to achieve a 2- to 3-log fecal coliform reduction. Liquid chemical disinfectants were attractive options because of their low capital costs. This led to an investigation of the feasibility of using hydrogen peroxide or peracetic acid. A method for measuring peroxycompounds (hydrogen peroxide or peracetic acid plus hydrogen peroxide) was developed using the peroxidase-based oxidation of 2,2'-azino-bis(3-ethylbenz-thiazoline-6-sulfuric acid) diammonium salt (ABTS) with hydrogen peroxide. The validity of the method was confirmed using effluent from the MUCWTP. Recovery was higher than 90% for peracetic acid levels as low as 1.0 mg/L. Quenching of hydrogen peroxide was achieved with 50-mg/L catalase; quenching of peracetic acid was achieved with 100 mg/L of sodium thiosulfate, followed by 50 mg/L of catalase. Batch disinfection tests were conducted on MUCWTP effluent. Hydrogen peroxide and peracetic acid in wastewater over time could be modeled as a second-order decay, with the decay "constant" being a function of the initial concentration of peroxycompounds. This function was the same for both hydrogen peroxide and peracetic acid, possibly indicating similar decomposition pathways in wastewater matrices. Disinfection was modeled using a modified Hom equation. Required doses of hydrogen peroxide to reach the target fecal coliform levels ranged from 106 to 285 mg/L, with the higher doses occurring when ferric chloride instead of alum was used as the coagulant. Hence, hydrogen peroxide was infeasible as a disinfectant for this application. On the other hand, the peracetic acid dose needed to

Suppression by ellagic acid of 60Co-irradiation-induced lipid peroxidation in placenta and fetus of rats

International Nuclear Information System (INIS)

Oku, Hirotsugu

1992-01-01

The effect of ellagic acid, a component of Eucalyptus maculata, on lipid peroxidation was examined in placenta and fetus of pregnant rats irradiated with 60 Co. The increase in lipid peroxide levels by the irradiation of the placenta and fetus brain as well as those of the serum and organs of mother was suppressed by treatment of the mother rats with ellagic acid. This suppressing effect found in placenta and fetus was significantly correlated with that found in mother rats. Moreover, ellagic acid suppressed the morphological changes such as degeneration in the endothelial cells of placenta and liver cells of fetus caused by the irradiation and improved the survival rate after the irradiation. These suppressing effects of ellagic acid were approximately the same as those of α-tocopherol. (author)

Lipid Peroxidation, Nitric Oxide Metabolites, and Their Ratio in a Group of Subjects with Metabolic Syndrome

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Gregorio Caimi

2014-01-01

Full Text Available Our aim was to evaluate lipid peroxidation, expressed as thiobarbituric acid-reactive substances (TBARS, nitric oxide metabolites (nitrite + nitrate expressed as NOx, and TBARS/NOx ratio in a group of subjects with metabolic syndrome (MS. In this regard we enrolled 106 subjects with MS defined according to the IDF criteria, subsequently subdivided into diabetic (DMS and nondiabetic (NDMS and also into subjects with a low triglycerides/HDL-cholesterol (TG/HDL-C index or with a high TG/HDL-C index. In the entire group and in the four subgroups of MS subjects we found an increase in TBARS and NOx levels and a decrease in TBARS/NOx ratio in comparison with normal controls. Regarding all these parameters no statistical difference between DMS and NDMS was evident, but a significant increase in NOx was present in subjects with a high TG/HDL-C index in comparison with those with a low index. In MS subjects we also found a negative correlation between TBARS/NOx ratio and TG/HDL-C index. Considering the hyperactivity of the inducible NO synthase in MS, these data confirm the altered redox and inflammatory status that characterizes the MS and suggest a link between lipid peroxidation, inflammation, and insulin resistance, evaluated as TG/HDL-C index.

Carbon catalysts for electrochemical hydrogen peroxide production in acidic media

DEFF Research Database (Denmark)

Čolić, Viktor; Yang, Sungeun; Révay, Zsolt

2018-01-01

Hydrogen peroxide is a commodity chemical, as it is an environmentally friendly oxidant. The electrochemical production of H2O2 from oxygen and water by the reduction of oxygen is of great interest, as it would allow the decentralized, on-site, production of pure H2O2. The ability to run...... the reaction in an acidic electrolyte with high performance is particularly important, as it would allow the use of polymer solid electrolytes and the production of pH-neutral hydrogen peroxide. Carbon catalysts, which are cheap, abundant, durable and can be highly selective show promise as potential catalysts...... for such systems. In this work, we examine the electrocatalytic performance and properties of seven commercially available carbon materials for H2O2 production by oxygen electroreduction. We show that the faradaic efficiencies for the reaction lie in a wide range of 18-82% for different carbon catalysts. In order...

Determination of cholesterol oxides in anchovies (Engraulis encrasicolus treated with a commercial mixture of citric acid, trisodium acid and hydrogen peroxide

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Aniello Anastasio

2013-02-01

Full Text Available A new additive formulation containing hydrogen peroxide, citric acid and trisodium acid is illegally used in fishery products due its whitening and antioxidant features. Aim of this study was to evaluate the possible presence of COPs and their role as markers of illegal treatment in anchovies (Engraulis encrasicolus stored at different temperatures. Sensory analysis was also performed by the specific QIM test. The quantitative determinations (% of cholesterol oxides (COPs showed changing amounts during storage. Not always The COPs measured in the treated samples were significantly higher than control samples. Considering the volatility of hydrogen peroxide and the poor repeatability of COPs analyses, as shown in the present study, it is crucial to intensify the control by the Authorities.

Lipid oxidation and fatty acid composition in salt-dried yellow croaker ( Pseudosciaena polyactis) during processing

Science.gov (United States)

Cai, Qiuxing; Wu, Yanyan; Li, Laihao; Wang, Yueqi; Yang, Xianqing; Zhao, Yongqiang

2017-10-01

Lipid oxidation in salt-dried yellow croaker ( Pseudosciaena polyactis) was evaluated during processing with commonly used analytical indices, such as the peroxide value (POV), the thiobarbituric acid reactive substances (TBARS) value, and oxidative-relative lipoxygenase (LOX) activity. Additionally, fatty acids were analyzed using gas chromatography-mass spectrometry. Both POV and TBARS increased significantly ( P acids were identified. Combined eicosapentaenoic acid (EPA; C20:5n3) and docosahexaenoic acid (DHA; C22:6n3) content varied between (19.20 ± 0.37) mg g-1 and (23.45 ± 1.05) mg g-1. The polyunsaturated fatty acid/saturated fatty acid (PUFA/SFA) ratio in yellow croaker was 0.73-1.10, and the n-6/n-3 PUFA ratio was approximately 0.13-0.20. The contents of most fatty acids varied significantly ( P acids are potential markers for evaluating lipid oxidation in fish muscle because there was a significant correlation between these markers and TBARS and LOX activity ( P 0.931.

The lipid peroxidation intensity of fungi strains from the orders Agaricales and Polyporales

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O. V. Fedotov

2016-07-01

Full Text Available This article is devoted to investigation of the dynamics of growth and level of spontaneous and induced lipid peroxidation intensity of Basidiomycetes strains grown by surface cultivation on a glucose-peptone medium. The materials of the research are mycelium and culture filtrates (CF of 57 strains (5 belong to 5 species from the order Polyporales s.l., and 52 belong to 7 species of the order Agaricales s.l.. To study the dynamics of growth we used a weighing method for determining the accumulation of absolutely dry biomass. Intensity of lipid peroxidation was determined by a modified spectrophotometric method for content of active to thiobarbituric acid products. It was found that the most productive in absolutely dry biomass accumulation were the strains Flammulina velutipes (Curt.: Fr. Sing. F-610 and Pleurotus eryngii (DC.: Fr. Quél. P-er. The level of spontaneous and induced LPO intensity in mycelia of all strains was higher than this figure in the culture filtrate and increased with the duration of cultivation. Dependencies between the content of lipid peroxidation products in the mycelia and CF were not established. The lowest values were recorded for biomass accumulation by the strains Pleurotus ostreatus (Jacq.: Fr. P. Kumm. P-14, P-192 and P. citrinopileatus Singer. Р-сіtr. Groups of basidiomycete cultures with different levels of TBA-AP were identified. Spontaneous and induced intensivity of lipid peroxidation in all studied strains of mycelia was higher than the figure in the culture filtrate. The intensity of lipid peroxidation in both mycelia and culture filtrate constantly increased, which can be explained by the growing shortage of certain nutrients (primarily carbon and increased concentration of metabolic products in the medium. The ratio of spontaneous and induced lipid peroxidation intensity is specific to each strain and is independent of its systematic position. Shifting of prooxidant-antioxidant balance to a

Effect of Withania Somnifera Root Powder on the Levels of Circulatory Lipid Peroxidation and Liver Marker Enzymes in Chronic Hyperammonemia

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B. Harikrishnan

2008-01-01

Full Text Available Withania somnifera (L Dunal (Solanaceae, commonly called Ashwagandha (Sanskrit is an Ayurvedic Indian medicinal plant, which has been widely used as a home remedy for several ailments. We have investigated the influence of W.somnifera root powder on the levels of circulatory ammonia, urea, lipid peroxidation products such as TBARS (thiobarbituric acid and reactive substances, HP (hydroperoxides and liver marker enzymes such as AST (aspartate transaminase, ALT (alanine transaminase and ALP (alkaline phosphatase, for its hepatoprotective effect in ammonium chloride induced hyperammonemia. Ammonium chloride treated rats showed a significant increase in the levels of circulatory ammonia, urea, AST, ALT, ALP, TBARS and HP. These changes were significantly decreased in rats treated with W.somnifera root powder and ammonium chloride. Our results indicate that W.somnifera offers hepatoprotection by influencing the levels of lipid peroxidation products and liver markers in experimental hyperammonemia and this could be due to (i the presence of alkaloids, withanolids and flavonoids, (ii normalizing the levels of urea and urea related compounds, (iii its free radical scavenging property and (iv its antioxidant property. The exact underlying mechanism is still unclear and further research needed.

Medicinal Mushroom Cracked-Cap Polypore, Phellinus rimosus (Higher Basidiomycetes) Attenuates Acute Ethanol-Induced Lipid Peroxidation in Mice.

Science.gov (United States)

Ajith, Thekkuttuparambil A; Janardhanan, Kainoor K

2015-01-01

Alcohol abuse and alcoholism remain one of the major health issues worldwide, especially in developing countries. The protective effect of Phellinus rimosus against acute alcohol-induced lipid peroxidation in the liver, kidney, and brain as well as its effect against antioxidant enzyme activity such as superoxide (SOD) and catalase (CAT) in the liver was evaluated in mice. Ethyl acetate extract of Ph. Rimosus (50 mg/kg body wt, p.o.) 1 h before each administration of alcohol (3 mL/kg, p.o.; total 2 doses at 24-h intervals) protected against lipid peroxidation in all organs and attenuated the decline of SOD and CAT activity in the liver. The fold increase in lipid peroxidation, including conjugated diene and thiobarbituric acid reactive substance (TBARS) levels, was highest in the liver. There were 2.6- and 1.5- fold increases in TBARS levels in the liver of the alcohol alone- and alcohol+Ph. Rimosus-treated groups, compared with that of the normal group. Activity of SOD and CAT in the liver of alcohol- and alcohol+Ph. Rimosus- treated animals was 9.05±1.38, 18.76±1.71, and 11.26±1.02, 31.58±3.35 IU/mg protein, respectively. Extract at 1 mg/mL inhibited 50.6% activity of aniline hydroxylase (CYP2E1) in liver homogenate. From these results, we concluded that the extract significantly protected against the lipid peroxidation. Protection in the liver may be due to the inhibitory effect on CYP2E1 as well as the direct radical scavenging effect of Ph. Rimosus, which warrants further research.

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

Science.gov (United States)

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

2011-01-01

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

Effect of the gamma radiation dose rate on psychrotrophic bacteria, thiobarbituric acid reactive substances, and sensory characteristics of mechanically deboned chicken meat.

Science.gov (United States)

Brito, Poliana P; Azevedo, Heliana; Cipolli, Kátia M V A B; Fukuma, Henrique T; Mourão, Gerson B; Roque, Cláudio V; Miya, Norma T; Pereira, José L

2011-03-01

Frozen samples of mechanically deboned chicken meat (MDCM) with skin were irradiated with gamma radiation doses of 0.0 kGy (control) and 3 kGy at 2 different radiation dose rates: 0.32 kGy/h (3 kGy) and 4.04 kGy/h (3 kGy). Batches of irradiated and control samples were evaluated during 11 d of refrigerated (2 ± 1 °C) storage for the following parameters: total psychrotrophic bacteria count, thiobarbituric acid reactive substances (TBARS), evaluation of objective color (L*, a*, and b*) and a sensory evaluation (irradiated odor, oxidized odor, pink and brown colors). No statistical difference (P > 0.05) was found amongst the TBARS values obtained for the MDCM samples irradiated with dose rates of 0.32 and 4.04 kGy/h. There was a significant increase (P radiation to mechanically deboned chicken meat will provide the food industry with information concerning the definition of the best processing conditions to maximize the sensory and food quality.

Investigation of Influential Parameters in Deep Oxidative Desulfurization of Dibenzothiophene with Hydrogen Peroxide and Formic Acid

OpenAIRE

Haghighat Mamaghani, Alireza; Fatemi, Shohreh; Asgari, Mehrdad

2013-01-01

An effective oxidative system consisting of hydrogen peroxide, formic acid, and sulfuric acid followed by an extractive stage were implemented to remove dibenzothiophene in the simulated fuel oil. The results revealed such a great performance in the case of H2O2 in the presence of formic and sulfuric acids that led to the removal of sulfur compounds. Sulfuric acid was employed to increase the acidity of media as well as catalytic activity together with formic acid. The oxidation reaction was ...

The criteria of critical runaway and stable temperatures of catalytic decomposition of hydrogen peroxide in the presence of hydrochloric acid

International Nuclear Information System (INIS)

Lu, K.-T.; Yang, C.-C.; Lin, P.-C.

2006-01-01

The hydrogen peroxide and hydrochloric acid are used in close proximity in the computer chip manufacture. The hydrochloric acid catalyzes an exothermic decomposition of hydrogen peroxide into oxygen and water. The accumulation of heat and non-condensable gas increases temperature and pressure in this reaction process always lead to runaway reaction and accident owing to inadvertent mixing. Thus, the chemical reaction hazard has to be clearly identified. Its critical runaway temperatures and unstable reaction criteria in this reaction process have to be determined urgently. In this investigation, we estimated its kinetic parameters at various volumetric ratios of the hydrogen peroxide to hydrochloric acid. Then, used these kinetic parameters to evaluate their critical temperatures and stable criteria in each reaction processes. The analytic results are important and useful for the design of safety system in the computer chip manufacture

Presence of hydrogen peroxide, a source of hydroxyl radicals, in acid electrolyzed water.

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Takayuki Mokudai

Full Text Available BACKGROUND: Acid electrolyzed water (AEW, which is produced through the electrolysis of dilute sodium chloride (NaCl or potassium chloride solution, is used as a disinfectant in various fields because of its potent antimicrobial activity. The hydroxyl radical, an oxygen radical species, is often suggested as a putative active ingredient for AEW antimicrobial activity. METHODOLOGY/PRINCIPAL FINDINGS: The aim of the present study is to detect hydroxyl radicals in AEW. The hydroxyl radicals in AEW prepared under different conditions were determined using an electron spin resonance (ESR technique. A signal from 5,5-dimethyl-1-pyrroline N-oxide (DMPO-OH, an adduct of DMPO and the hydroxyl radical, was detected in AEW prepared by double or triple electrolyses of 1% NaCl but not of 0.1% NaCl solution. Then the presence of hydrogen peroxide as a proposed source of hydroxyl radicals was examined using a combination of ESR and a Fenton reaction. The DMPO-OH signal was clearly detected, even in AEW prepared by single electrolysis of 0.1% NaCl solution, when ferrous sulfate was added to induce a Fenton reaction, indicating the presence of hydrogen peroxide in the AEW. Since sodium formate, a hydroxyl radical scavenger, did not affect the bactericidal activity of AEW, it is concluded that the radical is unlikely to contribute to the antimicrobial activity of AEW, although a small amount of the radical is produced from hydrogen peroxide. Dimethyl sulfoxide, the other hydroxyl radical scavenger used in the present study, canceled the bactericidal activity of AEW, accompanied by complete depletion of free available chlorine, suggesting that hypochlorous acid is probably a major contributor to the antimicrobial activity. CONCLUSIONS: It is strongly suggested that although hydrogen peroxide is present in AEW as a source of hydroxyl radicals, the antimicrobial activity of AEW does not depend on these radicals.

Insights into the role of oxidative stress in the pathology of Friedreich ataxia using peroxidation resistant polyunsaturated fatty acids

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M. Grazia Cotticelli

2013-01-01

Full Text Available Friedreich ataxia is an autosomal recessive, inherited neuro- and cardio-degenerative disorder characterized by progressive ataxia of all four limbs, dysarthria, areflexia, sensory loss, skeletal deformities, and hypertrophic cardiomyopathy. Most disease alleles have a trinucleotide repeat expansion in the first intron of the FXN gene, which decreases expression of the encoded protein frataxin. Frataxin is involved in iron–sulfur-cluster (ISC assembly in the mitochondrial matrix, and decreased frataxin is associated with ISC-enzyme and mitochondrial dysfunction, mitochondrial iron accumulation, and increased oxidative stress. To assess the role of oxidative stress in lipid peroxidation in Friedreich ataxia we used the novel approach of treating Friedreich ataxia cell models with polyunsaturated fatty acids (PUFAs deuterated at bis-allylic sites. In ROS-driven oxidation of PUFAs, the rate-limiting step is hydrogen abstraction from a bis-allylic site; isotopic reinforcement (deuteration of bis-allylic sites slows down their peroxidation. We show that linoleic and α-linolenic acids deuterated at the peroxidation-prone bis-allylic positions actively rescue oxidative-stress-challenged Friedreich ataxia cells. The protective effect of the deuterated PUFAs is additive in our models with the protective effect of the CoQ10 analog idebenone, which is thought to decrease the production of free radicals. Moreover, the administration of deuterated PUFAs resulted in decreased lipid peroxidation as measured by the fluorescence of the fatty acid analog C11-BODIPY (581/591 probe. Our results are consistent with a role for lipid peroxidation in Friedreich ataxia pathology, and suggest that the novel approach of oral delivery of isotope-reinforced PUFAs may have therapeutic potential in Friedreich ataxia and other disorders involving oxidative stress and lipid peroxidation.

The effect of ionizing radiation on the fatty acid composition of natural fats and on lipid peroxide formation

International Nuclear Information System (INIS)

Hammer, C.T.; Wills, E.D.

1979-01-01

The effects of irradiation doses of 200 to 1000 krad on the fatty acid composition of saturated and unsaturated natural food fats have been studied. Lard, coconut oil, corn oil, methyl linoleate and herring oil have been analysed before and after irradiation for lipid peroxide content and fatty acid composition. The effects of storage under varied conditions after irradiation have also been investigated. Irradiation doses of 200 to 1000 krad had little effect on the fatty acid compositions of saturated fats (lard and coconut oil) or of fats with a high antioxidant content (corn oil) but caused destruction of 98 per cent of the highly unsaturated acids (18:4, 20:5, 22:6) and 46 per cent of the diene acids (18:2) in herring oil. The destruction of the polyunsaturated fatty acids increased with increasing storage temperature and storage time. The destruction of polyunsaturated fatty acids was accompanied by an increase in lipid peroxide formation. It is considered that changes in fatty acid composition in natural foods after irradiation are important in consideration of the use of irradiation of food preservation. (author)

Five Decades with Polyunsaturated Fatty Acids: Chemical Synthesis, Enzymatic Formation, Lipid Peroxidation and Its Biological Effects

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Angel Catalá

2013-01-01

Full Text Available I have been involved in research on polyunsaturated fatty acids since 1964 and this review is intended to cover some of the most important aspects of this work. Polyunsaturated fatty acids have followed me during my whole scientific career and I have published a number of studies concerned with different aspects of them such as chemical synthesis, enzymatic formation, metabolism, transport, physical, chemical, and catalytic properties of a reconstructed desaturase system in liposomes, lipid peroxidation, and their effects. The first project I became involved in was the organic synthesis of [1-14C] eicosa-11,14-dienoic acid, with the aim of demonstrating the participation of that compound as a possible intermediary in the biosynthesis of arachidonic acid “in vivo.” From 1966 to 1982, I was involved in several projects that study the metabolism of polyunsaturated fatty acids. In the eighties, we studied fatty acid binding protein. From 1990 up to now, our laboratory has been interested in the lipid peroxidation of biological membranes from various tissues and different species as well as liposomes prepared with phospholipids rich in PUFAs. We tested the effect of many antioxidants such as alpha tocopherol, vitamin A, melatonin and its structural analogues, and conjugated linoleic acid, among others.

Hydrogen peroxide safety issues

International Nuclear Information System (INIS)

Conner, W.V.

1993-01-01

A literature survey was conducted to review the safety issues involved in handling hydrogen peroxide solutions. Most of the information found in the literature is not directly applicable to conditions at the Rocky Flats Plant, but one report describes experimental work conducted previously at Rocky Flats to determine decomposition reaction-rate constants for hydrogen peroxide solutions. Data from this report were used to calculate decomposition half-life times for hydrogen peroxide in solutions containing several decomposition catalysts. The information developed from this survey indicates that hydrogen peroxide will undergo both homogeneous and heterogeneous decomposition. The rate of decomposition is affected by temperature and the presence of catalytic agents. Decomposition of hydrogen peroxide is catalyzed by alkalies, strong acids, platinum group and transition metals, and dissolved salts of transition metals. Depending upon conditions, the consequence of a hydrogen peroxide decomposition can range from slow evolution of oxygen gas to a vapor, phase detonation of hydrogen peroxide vapors

Combined effects of lipid peroxidation and antioxidant status on carotid atherosclerosis in a population aged 59-71 y: The EVA Study. Etude sur le Vieillisement Artériel.

Science.gov (United States)

Bonithon-Kopp, C; Coudray, C; Berr, C; Touboul, P J; Fève, J M; Favier, A; Ducimetière, P

1997-01-01

There are few epidemiologic studies of the effects of lipid peroxidation and antioxidant status on atherosclerosis. The relation of lipid peroxidation evaluated by thiobarbituric acid-reactive substances (TBARS) and biological markers of antioxidant status to ultrasonographically assessed carotid atherosclerosis was examined from baseline data of a longitudinal study on cognitive and vascular aging (Etude sur le Vieillisement Artériel, the EVA Study). The study sample was composed of 1187 mean and women aged 59-71 y without any history of coronary artery disease or stroke. Ultrasound examination included measurements of intima-media thickness (IMT) on the common carotid arteries (CCAs) and at the site of plaques. After adjustment for conventional cardiovascular risk factors, erythrocyte vitamin E was significantly and negatively associated with CCA-IMT in both men and women whereas plasma selenium and carotenoids were not. No association was found between TBARS and CCA-IMT in either sex. However, TBARS were significantly higher in men with carotid plaques than in those without. This association was strengthened in men with concentrations of erythrocyte vitamin E, plasma selenium, and carotenoids below the lowest quartile. Our findings give some epidemiologic support to the hypothesis that lipid peroxidation and low antioxidant status are involved in the early phases of atherosclerosis.

Altinoz et al., Afr J Tradit Complement Altern Med. (2015) 12(5):1-7 ...

African Journals Online (AJOL)

Proff.Adewunmi

is a condition which levels of blood lipid fractions are dysregulated (Bhalodia et al., 2010). Blood lipids ... reacts when heated with thiobarbituric acid and creates a pink chromogen. .... MDA is used to evaluate the severity of lipid peroxidation, releasing the toxic effect of ROS, which oxidize unsaturated fatty acids in the cell.

The Potential Use of Secondary Metabolites in Moringa oleifera as an Antioxidant Source

OpenAIRE

A. Fitri; T. Toharmat; D. A. Astuti; H. Tamura

2015-01-01

This present study determined antioxidant activity, lipid peroxidation, total phenolic, total flavonoids and phytochemicals in moringa leaves and moringa stem. Analysis used in this study was 1, 1-diphenyl-2-picrylhydrazyl (DPPH) method for antioxidant activity, thiobarbituric acid reactive substances (TBARS) method for lipid peroxidation, Folin-Ciocalteu method for total phenolic, total flavonoid and UFLC (Ultrafast Liquid Chromatography) for identification and quantification of phenolic com...

Andrographolide Ameliorates Beta-Naphthoflavone-Induced CYP1A Enzyme Activity and Lipid Peroxidation in Hamsters with Acute Opisthorchiasis.

Science.gov (United States)

Udomsuk, Latiporn; Chatuphonprasert, Waranya; Jarukamjorn, Kanokwan; Sithithaworn, Paiboon

2016-01-01

Opisthorchis viverrini (OV) infection generates oxidative stress/free radicals and is considered as a primary cause ofcholangiocarcinoma since it primarily triggers sclerosing cholangitis. In this study, the impacts of andrographolide on acute opisthorchaisis in β-naphthoflavone (BNF)-exposed hamsters were investigated. Ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-demethylase (MROD) activities and Thiobarbituric acid reaction substances (TBARS) assay of andrographolide in acute opisthorchiasis in the BNF-exposed hamsters were assessed. The results showed that andrographolide ameliorated the hepatic CYP1A1 and CYP1A2 activities by decreases of the specific enzymatic reactions of EROD and MROD, respectively, in the BNF-exposed hamsters. Moreover, andrographolide lowered the formation of malondialdehyde in the livers and brains of the hamsters. These observations revealed the promising chemo-protective and antioxidant activities of andrographolide via suppression of the specific EROD and MROD reactions and lipid peroxidation against acute opisthorchiasis in the BNF-exposed hamsters.

Alleviative effects of litchi (Litchi chinensis Sonn. flower on lipid peroxidation and protein degradation in emulsified pork meatballs

Directory of Open Access Journals (Sweden)

Yi Ding

2015-09-01

Full Text Available To avoid or retard the lipid peroxidation of meat products, antioxidants are commonly added. Considering the safety and health of additives in meat products, consumers prefer natural antioxidants rather than synthetic ones. Gentisic acid and epicatechin were identified as the major phenolic acid and flavonoid, respectively, of litchi flowers (LFs. The physicochemical properties of pork meatballs with or without dried LF powders (0.5%, 1.0%, and 1.5%, w/w and tert-butylhydroquinone (TBHQ; 0.01%, w/w were analyzed during a 4-week frozen storage period. LF and TBHQ decreased (p < 0.05 thiobarbituric acid reactive substance (TBARS values but increased (p < 0.05 thiol group contents in meatballs. LF added to meatballs improved (p < 0.05 texture and water-holding capacity (centrifugation/purge losses more than in the control group upon the storage. Although LF powders made meatballs redder and darker (p < 0.05 than the control and TBHQ groups, they did not affect the preference of panelists. The addition of 0.5% LF powders exhibited the best (p < 0.05 overall sensory panel acceptance. LFs may be an effective natural antioxidant to reduce lipid and protein oxidation for frozen cooked meat products.

Degradation of 2,4-dichlorophenoxyacetic acid in water by ozone-hydrogen peroxide process

Institute of Scientific and Technical Information of China (English)

YU Ying-hui; MA Jun; HOU Yan-jun

2006-01-01

This study reports an investigation into the degradation of 2,4-dichlorophenoxyacetic acid in bubble contactor column by O3/H2O2 process, which is widely used as a principal advanced oxidation process. The degradation of 2,4-dichlorophenoxyacetic acid was studied under different H2O2/O3 molar ratio and pH value. Meanwhile, TOC removal was investigated both in distilled water and tap water. The influences of ozone transfer and consumed hydrogen peroxide were also discussed. The degradation products and oxidation intermediates were identified by GC-MS and LC-MS. A possible reaction mechanism was thus proposed.

Kinetics of Oxidation of Cobalt(III Complexes of a Acids by Hydrogen Peroxide in the Presence of Surfactants

Directory of Open Access Journals (Sweden)

Mansur Ahmed

2008-01-01

Full Text Available Hydrogen peroxide oxidation of pentaamminecobalt(III complexes of α-hydroxy acids at 35°C in micellar medium has been attempted. In this reaction the rate of oxidation shows first order kinetics each in [cobalt(III] and [H2O2]. Hydrogen peroxide induced electron transfer in [(NH35 CoIII-L]2+ complexes of α-hydroxy acids readily yields 100% of cobalt(II with nearly 100% of C-C bond cleavage products suggesting that it behaves mainly as one equivalent oxidant in micellar medium. With unbound ligand also it behaves only as C-C cleavage agent rather than C-H cleavage agent. With increasing micellar concentration an increase in the rate is observed.

Effect of high-energy electron irradiation of chicken meat on thiobarbituric acid values, shear values, odor, and cooked yield

International Nuclear Information System (INIS)

Heath, J.L.; Owens, S.L.; Tesch, S.; Hannah, K.W.

1990-01-01

Experiments were conducted to determine whether electron-beam irradiation would affect shear values, yield, odor, and thiobarbituric acid (TBA) values of chicken tissues. Broiler breasts (pectoralis superficialis) and whole thighs were irradiated with an electron-beam accelerator at levels to produce adsorbed doses of 100, 200, and 300 krads on the surface of the sample. The thigh samples were stored for 2, 4, and 8 days before testing for TBA values. The depth to which the radiation had penetrated the pectoralis superficialis muscle was also determined. Radiation penetrated 22 mm into slices of pectoralis superficialis muscle when 100 krad was absorbed by the surface of the tissue. The dose absorbed beneath the tissue surface to a depth of 10 mm was larger than the dose absorbed at the surface. The absorbed dose decreased as the depth of penetration increased. For cooked breast tissue, the shear values and moisture content were not affected by the absorbed radiation. Cooking losses of aged breast tissue were not affected by irradiation, but cooking losses were reduced in breast tissue that had not been aged. Irradiating uncooked thigh and uncooked breast samples produced a characteristic odor that remained after the thighs were cooked but was not detectable after the breast samples were cooked. With two exceptions, no significantly different TBA values were found that could be attributed to irradiation

Surface enhancement Raman scattering of tautomeric thiobarbituric acid. Natural bond orbitals and B3LYP/6-311+G (d, p) assignments of the Fourier Infrared and Fourier Raman Spectra.

Science.gov (United States)

Soto, C A Téllez; Ramos, J M; Costa Junior, A C; Vieira, Laís S; Rangel, João L; Raniero, L; Fávero, Priscila P; Lemma, Tibebe; Ondar, Grisset F; Versiane, Otavio; Martin, A A

2013-10-01

Surface enhancement Raman scattering (SERS) of two tautomer of thiobarbituric acid was obtained using silver and gold nanoparticles. Large band enhancement in the region of the ν(C=S), ν(C=C), δ(CH2), and δ(CNH) vibrational modes was found. Natural bond analysis of the tautomer species revealed expressive values of charge transfer, principally from lone pair electron orbitals of the S, N, and O atoms. Complete vibrational assignment was done for the two tautomers using the B3LYP/6-311+G (d, p) procedure, band deconvolution analysis, and from a rigorous interpretation of the normal modes matrix. The calculated spectra agree well with the experimental ones. Copyright © 2013 Elsevier B.V. All rights reserved.

Evaporation of iodine from nitric acid with the aid of peroxide

International Nuclear Information System (INIS)

Cathers, G.I.; Shipman, C.J.

1975-01-01

Traces of radioactive iodine with a concentration of 5 x 10 -4 M or less that remained in nitric acid solution after reprocessing of nuclear fuels can, without great apparatus effort, be distilled off as hydrogen iodide by continuous addition of hydrogen peroxide to the solution boiling at about 105 0 C to 1,15 0 C, and then be separated as elementary iodine. Starting from a 4 to 6 molecular nitric acid solution, the H 2 O 2 -concentration amounts to 0.012 percentage by weight and is kept at this level during the entire distillation process. The iodine concentration is also profitably kept at the level of the starting solution by adding non-radioactive iodine, since an isotopec exchange of radioactive iodine bound in organic impurities is advanced in that way. (UWI) [de

Daconate Herbicide Toxicity on Lipid Peroxidation And Antioxidant Enzymes in Blood of Rats

International Nuclear Information System (INIS)

Tawfik, S.M.F.

2005-01-01

The effect of daconate herbicide on lipid peroxidation and antioxidant enzyme systems was investigated in rats after one and two weeks post-treatment. Animals were treated daily with an oral dose of 18 mg/kg body weight or 90 mg/kg body weight daconate for one and two consecutive weeks. Lipid peroxide content, as thiobarbituric acid reactive substances (TBARS), was determined in blood of rats as indication for cytotoxicity. Blood glutathion (GSH), gamma glutamyl transpeptidase (γ GT) and superoxide dismutase (SOD) were estimated as indication of antioxidant status. Also, daconate effect on peroxidase action of catalase in rats was studied using 14 C -formate. The results revealed significant elevation in TBARS level and γ GT activity accompanied by reduced level of GSH content and SOD activity after treatment of rats with a daily oral dose of 90 mg/kg for one and two weeks and also in rats treated with 18 mg/kg daconate for two weeks. Rats treated with daconate at the dose level of 18 mg/kg for one week revealed non-appreciable changes in the tested parameters of blood as compared to the control ones. Radioactivities eliminated in both the expired air and in urine were reduced at the dose level of 90 mg/kg after one and two weeks, while it were reduced only after two weeks at the dose level of 18 mg/kg daconate. The data revealed that daconate had a marked effect on the activities of catalase enzyme in blood and liver of treated rats

Investigations of antioxidant-mediated protection and mitigation of radiation-induced DNA damage and lipid peroxidation in murine skin.

Science.gov (United States)

Jelveh, Salomeh; Kaspler, Pavel; Bhogal, Nirmal; Mahmood, Javed; Lindsay, Patricia E; Okunieff, Paul; Doctrow, Susan R; Bristow, Robert G; Hill, Richard P

2013-08-01

Radioprotection and mitigation effects of the antioxidants, Eukarion (EUK)-207, curcumin, and the curcumin analogs D12 and D68, on radiation-induced DNA damage or lipid peroxidation in murine skin were investigated. These antioxidants were studied because they have been previously reported to protect or mitigate against radiation-induced skin reactions. DNA damage was assessed using two different assays. A cytokinesis-blocked micronucleus (MN) assay was performed on primary skin fibroblasts harvested from the skin of C3H/HeJ male mice 1 day, 1 week and 4 weeks after 5 Gy or 10 Gy irradiation. Local skin or whole body irradiation (100 kVp X-rays or caesium (Cs)-137 γ-rays respectively) was performed. DNA damage was further quantified in keratinocytes by immunofluorescence staining of γ-histone 2AX (γ-H2AX) foci in formalin-fixed skin harvested 1 hour or 1 day post-whole body irradiation. Radiation-induced lipid peroxidation in the skin was investigated at the same time points as the MN assay by measuring malondialdehyde (MDA) with a Thiobarbituric acid reactive substances (TBARS) assay. None of the studied antioxidants showed significant mitigation of skin DNA damage induced by local irradiation. However, when EUK-207 or curcumin were delivered before irradiation they provided some protection against DNA damage. In contrast, all the studied antioxidants demonstrated significant mitigating and protecting effects on radiation-induced lipid peroxidation at one or more of the three time points after local skin irradiation. Our results show no evidence for mitigation of DNA damage by the antioxidants studied in contrast to mitigation of lipid peroxidation. Since these agents have been reported to mitigate skin reactions following irradiation, the data suggest that changes in lipid peroxidation levels in skin may reflect developing skin reactions better than residual post-irradiation DNA damage in skin cells. Further direct comparison studies are required to confirm

Optimization of Fluorescent Silicon Nano material Production Using Peroxide/ Acid/ Salt Technique

International Nuclear Information System (INIS)

Abuhassan, L.H.

2009-01-01

Silicon nano material was prepared using the peroxide/ acid/ salt technique in which an aqueous silicon-based salt solution was added to H 2 O 2 / HF etchants. In order to optimize the experimental conditions for silicon nano material production, the amount of nano material produced was studied as a function of the volume of the silicon salt solution used in the synthesis. A set of samples was prepared using: 0, 5, 10, 15, and 20 ml of an aqueous 1 mg/ L metasilicate solution. The area under the corresponding peaks in the infrared (ir) absorption spectra was used as a qualitative indicator to the amount of the nano material present. The results indicated that using 10 ml of the metasilicate solution produced the highest amount of nano material. Furthermore, the results demonstrated that the peroxide/ acid/ salt technique results in the enhancement of the production yield of silicon nano material at a reduced power demand and with a higher material to void ratio. A model in which the silicon salt forms a secondary source of silicon nano material is proposed. The auxiliary nano material is deposited into the porous network causing an increase in the amount of nano material produced and a reduction in the voids present. Thus a reduction in the resistance of the porous layer, and consequently reduction in the power required, are expected. (author)

Dietary docosahexaenoic acid-induced generation of liver lipid peroxides is not suppressed further by elevated levels of glutathione in ODS rats.

Science.gov (United States)

Sekine, Seiji; Kubo, Kazuhiro; Tadokoro, Tadahiro; Saito, Morio

2006-04-01

We examined the effects of ascorbic acid (AsA) and glutathione (GSH; experiment 1) and of GSH in acetaminophen-fed rats (experiment 2) on dietary docosahexaenoic acid (DHA)-induced tissue lipid peroxidation. In experiment 1, AsA-requiring Osteogenic Disorder Shionogi/Shi-od/od (ODS) rats were fed soybean protein diets containing DHA (10.0% total energy) and AsA at 50 (low) or 300 (normal) mg/kg without (low) or with (normal) methionine at 2 g/kg for 32 d. In experiment 2, ODS rats were fed diets containing DHA (7.8% total energy) and acetaminophen (4 g/kg) with different levels of dietary methionine (low, moderate, high, and excessive at 0, 3, 6, and 9 g/kg, respectively) for 30 d. Tissue lipid peroxides and antioxidant levels were determined. In experiment 1, liver lipid peroxide levels in the low-AsA group were lower than those in the normal-AsA group, but kidney and testis lipid peroxide levels in the low-AsA group were higher than those in the normal-AsA group. Dietary methionine tended to decrease tissue lipid peroxide levels but did not decrease vitamin E (VE) consumption. In experiment 2, a high level of methionine (6 g/kg) decreased liver lipid peroxide levels and VE consumption. However, generation of tissue lipid peroxides and VE consumption were not decreased further by a higher dose of methionine (9 g/kg). Higher than normal levels of dietary methionine are not necessarily associated with decreased dietary DHA-induced generation of tissue lipid peroxides and VE consumption except that the GSH requirement is increased in a condition such as acetaminophen feeding.

Effects of heat and ultraviolet radiation on the oxidative stability of pine nut oil supplemented with carnosic acid.

Science.gov (United States)

Wang, Han; Zu, Ge; Yang, Lei; Zu, Yuan-gang; Wang, Hua; Zhang, Zhong-hua; Zhang, Ying; Zhang, Lin; Wang, Hong-zheng

2011-12-28

The effects of carnosic acid (CA) of different concentrations (0.05, 0.1, and 0.2 mg/g) and two common antioxidants (butylated hydroxytoluene and α-tocopherol) on oxidative stability in pine nut oil at different accelerated conditions (heating and ultraviolet radiation) were compared. The investigation focused on the increase in peroxide and conjugated diene values, as well as free fatty acid and thiobarbituric acid-reactive substances. The changes in trans fatty acid and aldehyde compound contents were investigated by Fourier transform infrared spectroscopy, while the changes in pinolenic acid content were monitored by gas chromatography-mass spectrometry. The results show that CA was more effective in restraining pine nut oil oxidation under heating, UV-A and UV-B radiation, in which a dose-response relationship was observed. The antioxidant activity of CA was stronger than that of α-tocopherol and butylated hydroxytoluene. Pine nut oil supplemented with 0.2 mg/g CA exhibited favorable antioxidant effects and is preferable for effectively avoiding oxidation.

Protective Effect of Pulp Oil Extracted from Canarium odontophyllum Miq. Fruit on Blood Lipids, Lipid Peroxidation, and Antioxidant Status in Healthy Rabbits

Directory of Open Access Journals (Sweden)

Faridah Hanim Shakirin

2012-01-01

Full Text Available The aim of this paper was to compare the effects of pulp and kernel oils of Canarium odontophyllum Miq. (CO on lipid profile, lipid peroxidation, and oxidative stress of healthy rabbits. The oils are rich in SFAs and MUFAs (mainly palmitic and oleic acids. The pulp oil is rich in polyphenols. Male New Zealand white (NZW rabbits were fed for 4 weeks on a normal diet containing pulp (NP or kernel oil (NK of CO while corn oil was used as control (NC. Total cholesterol (TC, HDL-C, LDL-c and triglycerides (TG levels were measured in this paper. Antioxidant enzymes (superoxide dismutase and glutathione peroxidise, thiobarbiturate reactive substances (TBARSs, and plasma total antioxidant status (TAS were also evaluated. Supplementation of CO pulp oil resulted in favorable changes in blood lipid and lipid peroxidation (increased HDL-C, reduced LDL-C, TG, TBARS levels with enhancement of SOD, GPx, and plasma TAS levels. Meanwhile, supplementation of kernel oil caused lowering of plasma TC and LDL-C as well as enhancement of SOD and TAS levels. These changes showed that oils of CO could be beneficial in improving lipid profile and antioxidant status as when using part of normal diet. The oils can be used as alternative to present vegetable oil.

Lipoic acid in combination with a chelator ameliorates lead-induced peroxidative damages in rat kidney

Energy Technology Data Exchange (ETDEWEB)

Sivaprasad, R.; Nagaraj, M.; Varalakshmi, P. [Department of Medical Biochemistry, University of Madras (Taramani), Chennai 600 113 (India)

2002-08-01

The deleterious effect of lead has been attributed to lead-induced oxidative stress with the consequence of lipid peroxidation. The present study was designed to investigate the combined effect of DL-{alpha}-lipoic acid (LA) and meso-2,3-dimercaptosuccinic acid (DMSA) on lead-induced peroxidative damages in rat kidney. The increase in peroxidated lipids in lead-poisoned rats was accompanied by alterations in antioxidant defence systems. Lead acetate (Pb, 0.2%) was administered in drinking water for 5 weeks to induce lead toxicity. LA (25 mg/kg body weight per day i.p) and DMSA (20 mg/kg body weight per day i.p) were administered individually and also in combination during the sixth week. Nephrotoxic damage was evident from decreases in the activities of {gamma}-glutamyl transferase and N-acetyl {beta}-D-glucosaminidase, which were reversed upon combined treatment with LA and DMSA. Rats subjected to lead intoxication showed a decline in the thiol capacity of the cell, accompanied by high malondialdehyde levels along with lowered activities of catalase, superoxide dismutase, glutathione peroxidase and glutathione metabolizing enzymes (glutathione reductase, glucose-6-phosphate dehydrogenase, glutathione-S-transferase). Supplementation with LA as a sole agent showed considerable changes over oxidative stress parameters. The study has highlighted the combined effect of both drugs as being more effective in reversing oxidative damage by bringing about an improvement in the reductive status of the cell. (orig.)

A new synthetic methodology for the preparation of biocompatible and organo-soluble barbituric- and thiobarbituric acid based chitosan derivatives for biomedical applications

Energy Technology Data Exchange (ETDEWEB)

Shahzad, Sohail [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Shahzadi, Lubna [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Mahmood, Nasir [Department of Allied Health Sciences and Chemical Pathology, Department of Human Genetics and Molecular Biology, University of Health Sciences, Lahore (Pakistan); Siddiqi, Saadat Anwar [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Rauf, Abdul [Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Manzoor, Faisal; Chaudhry, Aqif Anwar [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Rehman, Ihtesham ur [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Materials Science and Engineering, The Kroto Research Institute, The University of Sheffield, North Campus, Broad Lane, Sheffield, S3 7HQ (United Kingdom); Yar, Muhammad, E-mail: drmyar@ciitlahore.edu.pk [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan)

2016-09-01

Chitosan's poor solubility especially in organic solvents limits its use with other organo-soluble polymers; however such combinations are highly required to tailor their properties for specific biomedical applications. This paper describes the development of a new synthetic methodology for the synthesis of organo-soluble chitosan derivatives. These derivatives were synthesized from chitosan (CS), triethyl orthoformate and barbituric or thiobarbituric acid in the presence of 2-butannol. The chemical interactions and new functional motifs in the synthesized CS derivatives were evaluated by FTIR, DSC/TGA, UV/VIS, XRD and {sup 1}H NMR spectroscopy. A cytotoxicity investigation for these materials was performed by cell culture method using VERO cell line and all the synthesized derivatives were found to be non-toxic. The solubility analysis showed that these derivatives were readily soluble in organic solvents including DMSO and DMF. Their potential to use with organo-soluble commercially available polymers was exploited by electrospinning; the synthesized derivatives in combination with polycaprolactone delivered nanofibrous membranes. - Highlights: • Development of a new synthetic methodology • Synthesis of organo-soluble chitosan (CS) derivatives • VERO cells proliferation • Nanofibrous membranes from the synthesized chitosan derivatives and polycaprolactone.

Effect of antioxidants and silicates on peroxides in povidone.

Science.gov (United States)

Narang, Ajit S; Rao, Venkatramana M; Desai, Divyakant S

2012-01-01

Reactive peroxides in povidone often lead to degradation of oxidation-labile drugs. To reduce peroxide concentration in povidone, the roles of storage conditions, antioxidants, and silicates were investigated. Povidone alone and its physical mixtures with ascorbic acid, propyl gallate, sodium sulfite, butylated hydroxyanisole (BHA), or butylated hydroxytoluene (BHT) were stored at 25 °C and 40 °C, at 11%, 32%, and 50% relative humidity. In addition, povidone solution in methanol was equilibrated with silicates (silica gel and molecular sieves), followed by solvent evaporation to recover povidone powder. Peroxide concentrations in povidone were measured. The concentration of peroxides in povidone increased under very-low-humidity storage conditions. Among the antioxidants, ascorbic acid, propyl gallate, and sodium sulfite reduced the peroxide concentration in povidone, whereas BHA and BHT did not. Water solubility appeared to determine the effectiveness of antioxidants. Also, some silicates significantly reduced peroxide concentration in povidone without affecting its functionality as a tablet binder. Porosity of silicates was critical to their ability to reduce the peroxide concentration in povidone. A combination of these approaches can reduce the initial peroxide concentration in povidone and minimize peroxide growth under routine storage conditions. Copyright © 2011 Wiley-Liss, Inc.

Coprecipitation of thorium and uranium peroxides from acid solutions

Energy Technology Data Exchange (ETDEWEB)

McTaggart, D.R.; Mailen, J.C.

1981-01-01

The factors affecting successful coprecipitation of thorium and uranium peroxides from acid media were studied. Variables considered in this work were H/sup +/ concentration, H/sub 2/O/sub 2/ concentration, duration of contact, and rate of feed solution addition. In all experiments, stock solutions of Th(NO/sub 3/)/sub 4/ and UO/sub 2/(NO/sub 3/)/sub 2/ were fed at a controlled rate into H/sub 2/O/sub 2/ solutions with constant stirring. Samples were taken as a function of time to follow the H/sup +/ concentration of the solution, uranium precipitation, thorium precipitation, precipitant weight/volume of solution, and crystalline structure and growth. The optimum conditions for maximum coprecipitation are low H/sup +/ concentration, high H/sub 2/O/sub 2/ concentration, and extended contact time between the solutions.

Thermal stability of butter oils produced from sheep’s non-pasteurized and pasteurized milk

Directory of Open Access Journals (Sweden)

FLAVIA POP

Full Text Available The physical and chemical characteristics and thermal stability of butter oil produced from non-pasteurized and pasteurized sheep’s milk were studied. Thermal stability of samples was estimated by using the accelerated shelf-life testing method. Samples were stored at 50, 60 and 70oC in the dark and the reaction was monitored by measuring peroxide, thiobarbituric acid and free fatty acid values. The peroxide and thiobarbituric acid values increased as the temperature increased. The increase of acid values of the two samples was not significant. A slight increase in free fatty acid value showed that hydrolytic reactions were not responsible for the deterioration of butter oil samples in thermal stability studies. When compared, butter oil produced from pasteurized sheep’s milk has higher thermal stability than butter oil produced from non-pasteurized sheep’s milk. Although butter oil produced from non-pasteurized milk was not exposed to any heat treatment, the shelf-life of this product was lower than the shelf-life of butter oil produced from pasteurized sheep’s milk. Therefore, heat treatment for pasteurization did not affect the thermal stability of butter oil.

Radiation effect on lipid peroxide content of spices

International Nuclear Information System (INIS)

Kaneko, Nobutada; Ito, Hitoshi; Ishigaki, Isao

1990-01-01

To evaluate the radiation-induced deterioration of lipid in spices, peroxide value, iodine value and acid value were measured after extraction by chloroform. Peroxide values of black pepper and white pepper were not increased by gamma-irradiation with doses below 30 kGy and gradually increased at higher dose up to 80 kGy in this study. On contrary, peroxide values of clove and rosemary increased rather quickly below 20 kGy of gamma-irradiation, and they became stationary at higher dose. Iodine values and acid values had relationship with peroxide values on each kind of spices. On the storage study of irradiated spices, peroxide values decreased quickly during 20 days storage as same as nonirradiated spices, and it became stationary after 20 to 50 days storage at 30degC. Enhancement of oxidized deterioration were not observed even higher irradiation doses up to 80 kGy in this study. (author)

The thermodynamic characteristics of the reaction between vanadium(5) and hydrogen peroxide in concentrated solutions of perchloric acid

International Nuclear Information System (INIS)

Vorob'ev, P.N.; Dmitrieva, N.G.; Poteshonkova, T.A.

2001-01-01

Stability constants of vanadium(5) complex with hydrogen peroxide and enthalpy of vanadium(5) complexing with hydrogen peroxide are determined at acidity of solution c(H + ) = 5.00 mol/l, temperature T = 298.15 K and values of ionic force: I = 5, 6 and 7. Standard thermodynamic characteristics of vanadium(5) peroxide complex formation were calculated. At zeroth ionic force the value of complexing enthalpy Δ r H 298.15 deg is equal to -48.59 ± 0.33 kJ/mol, standard enthalpy of peroxide vanadium(5) complex formation Δ f H 298.15 deg is equal to -895.49 ± 1.51 kJ/mol; Δ r G 298.15 deg = -36.51 kJ/mol, Δ r S 298.15 deg -40.51 J/(mol K). As it is shown by calculations, standard change in entropy of the reaction has a minus sign, that is unique to complexation with neutral ligand [ru

Ascorbic acid improves the antioxidant activity of European grape juices by improving the juices' ability to inhibit lipid peroxidation of human LDL in vitro

DEFF Research Database (Denmark)

Landbo, Anne-Katrine Regel; Meyer, Anne Boye Strunge

2001-01-01

. Red grape juice concentrate inhibited lipid peroxidation of LDL by prolonging the lag phase by 2.7 times relative to a control when evaluated at a total phenolic concentration of 10 muM gallic acid equivalents (GAE). Both red grape juices tested blocked lipid peroxidation of LDL at 20 muM GAE. White.......96, P acid alone did not exert antioxidant activity towards LDL, but combinations of 5 muM ascorbic acid with 5 muM GAE juice phenols eliminated the prooxidant activity of white grape juice, and significantly...

Radiation effects on physicochemical characteristics of pork

International Nuclear Information System (INIS)

Li Xin; Cheng Wei; Xiong Guangquan; Geng Shengrong; Qiao Yu; Liao Tao; Liao Li; Lin Ruotai

2011-01-01

Pork samples were soaked in antioxidant solution (1 g/L), vacuum-packaged,irradiated at 3 kGy by Co γ-rays or 10 MeV electron beams,and refrigerated at 0 degree C-4 degree C for 30 d. On Day 1, 10, 20, 25 and 30 post irradiation, total bacterial counts,peroxide values, thiobarbituric acid reactive substances, volatiles and off-odor of the irradiated pork samples were analyzed. The total bacterial counts were <10 cfu/g on Day 30. The peroxide values, thiobarbituric acid reactive substances and volatiles contents of pork irradiated by the γ-rays were higher than pork irradiated by electron beams. Pork irradiated by γ-rays combined with antioxidant treatment was most close to the control in odor, with a similarity of 89.68%. The results showed that E-beam irradiation reduced lipid oxidation and volatiles contents, γ-ray irradiation helped to reduce off-odor, and addition of antioxidant could effectively reduce lipid oxidation and off-odor. (authors)

A new ion imprinted polymer based on Ru(III)-thiobarbituric acid complex for solid phase extraction of ruthenium(III) prior to its determination by ETAAS

International Nuclear Information System (INIS)

Zambrzycka, Elżbieta; Godlewska-Żyłkiewicz, Beata

2014-01-01

A new ruthenium ion imprinted polymer was prepared from the Ru(III) 2-thiobarbituric acid complex (the template), methacrylic acid or acrylamide (the functional monomers), and ethylene glycol dimethacrylate (the cross-linking agent) using 2,2′-azobisisobutyronitrile as the radical initiator. The ion imprinted polymer was characterized and used as a selective sorbent for the solid phase extraction of Ru(III) ions. The effects of type of functional monomer, sample volume, solution pH and flow rate on the extraction efficiency were studied in the dynamic mode. Ru(III) ion was quantitatively retained on the sorbents in the pH range from 3.5 to 10, and can be eluted with 4 mol L−1 aqueous ammonia. The affinity of Ru(III) for the ion imprinted polymer based on the acrylamide monomer is weaker than that for the polymer based on the methacrylic acid monomer, which therefore was used in interference studies and in analytical applications. Following extraction of Ru(III) ions with the imprint and their subsequent elution from the polymer with aqueous ammonia, Ru(III) was detected by electrothermal atomic absorption spectrometry with a detection limit of 0.21 ng mL −1 . The method was successfully applied to the determination of trace amounts of Ru(III) in water, waste, road dust and platinum ore (CRM SARM 76) with a reproducibility (expressed as RSD) below 6.4 %. (author)

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

Science.gov (United States)

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

2003-04-01

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

Salivary DNA and markers of oxidative stress in patients with chronic periodontitis.

Science.gov (United States)

Baňasová, Lenka; Kamodyová, Natália; Janšáková, Katarína; Tóthová, Ľubomíra; Stanko, Peter; Turňa, Ján; Celec, Peter

2015-03-01

Previous observational studies have shown that periodontal status is associated with salivary markers of oxidative damage. A direct comparison of periodontitis patients and controls using a wide palette of salivary markers of oxidative stress is lacking. Characteristics of salivary DNA in periodontitis are unknown. The aim of this study was to compare the salivary markers of oxidative stress and characteristics of salivary DNA between patients with chronic periodontitis and periodontitis-free controls. Saliva was collected from 23 patients with chronic periodontitis and 19 periodontitis-free controls. All participants underwent a clinical periodontal examination. Markers of oxidative and carbonyl stress were measured in saliva. Human and bacterial DNA was quantified, and human DNA integrity was assessed. Salivary thiobarbituric acid-reacting substances were higher in patients than in controls; at least in men, the difference was significant (p periodontitis patients. The results confirmed the association of salivary thiobarbituric acid-reacting substances with periodontitis. Lipid peroxidation in periodontitis seems to be caused by increased production of reactive oxygen species in men and by decreased antioxidant status in women. Whether lower salivary DNA integrity is involved in the pathogenesis of periodontitis remains to be elucidated. Salivary thiobarbituric acid-reacting substances are associated with periodontitis at least on a population level. Sex-specific causes of lipid peroxidation might point towards different pathogenic mechanisms.

Relation of fatty acid composition in lead-exposed mallards to fat mobilization, lipid peroxidation and alkaline phosphatase activity

Science.gov (United States)

Mateo, R.; Beyer, W.N.; Spann, J.W.; Hoffman, D.J.

2003-01-01

The increase of n-6 polyunsaturated fatty acids (PUFA) in animal tissues has been proposed as a mechanism of lead (Pb) poisoning through lipid peroxidation or altered eicosanoids metabolism. We have studied fatty acid (FA) composition in liver and brain of mallards (Anas platyrhynchos) feeding for 3 weeks on diets containing combinations of low or high levels of vitamin E (20 or 200 UI/kg) and Pb (0 or 2 g/kg). Saturated FA, n-6 PUFA and total concentrations of FA were higher in livers of Pb-exposed mallards, but not in their brains. The percentage of n-6 PUFA in liver and brain was slightly higher in Pb-exposed mallards. The increase of n-6 PUFA in liver was associated with decreased triglycerides and increased cholesterol in plasma, thus could be in part attributed to feed refusal and fat mobilization. The hepatic ratios between adrenic acid (22:4 n-6) and arachidonic acid (20:4 n-6) or between adrenic acid and linoleic acid (18:2 n-6) were higher in Pb exposed birds, supporting the existing hypothesis of increased fatty acid elongation by Pb. Among the possible consequences of increased n-6 PUFA concentration in tissues, we found increased lipid peroxidation in liver without important histopathological changes, and decreased plasma alkaline phosphatase activity that may reflect altered bone metabolism in birds.

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

International Nuclear Information System (INIS)

Horton, Jureta W.

2003-01-01

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

COMPARATIVE STUDIES ON EFFECTS OF FREEZING ON PHYSICOCHEMICAL PROPERTIES OF FILLETS TWO FISH SPECIES IN IRAN

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Ali Aberoumand

2018-04-01

Full Text Available Because of fishes Sparidentex hasta and Pampus argenteus in the southern of Iran are consumed abundant in a particular season and it should be frozen for consumption throughout the year. Therefore, this research was carried out to investigate the effects of freezing on some of the physicochemical properties of fillets the fishes. Factors such as fat with chloroform-methanol method, amount of TBA (Thiobarbituric acid in fish muscle accordance method of Pearson, pH using a pH meter, FFA (Free fatty acids with titration in the presence of phenolphthalein was determined based on the percentage of oleic acid, peroxide value according to AOAC (Association of Official Analytical Chemists, in fresh samples at time zero and after different periods of freezing were tested respectively. Result showd that TBA (Thiobarbituric acid content in fish fillet, found Pampus argenteus and Sparidentex hasta 0.65 and 0.53 respectively. The results showed that the highest percentage of fat found for Pampus argenteus at 95 days 24.2(%2 and for Sparidentex hasta at 35 days (25.19%, free fatty acids contents found highest (0.9% and (0.97% for Sparidentex hasta and Pampus argenteus after 95 days. It can conclude that the TBA (Thiobarbituric acid, FFA (Free fatty acids  contents and pH of both fish species during storage in freezer were increased. Peroxide value in fish Pampus argenteus was reduced but, in Sparidentex hasta showed no significant differently.  The best time of storage of fishes Pampus argenteus and Sparidentex hasta at -18 °C was 35 days freezing, but nutritional value of fillets and fatty acids greatly reduced

Polyester Sulphonic Acid Interstitial Nanocomposite Platform for Peroxide Biosensor

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Emmanuel I. Iwuoha

2009-12-01

Full Text Available A novel enzyme immobilization platform was prepared on a platinum disk working electrode by polymerizing aniline inside the interstitial pores of polyester sulphonic acid sodium salt (PESA. Scanning electron microscopy study showed the formation of homogeneous sulphonated polyaniline (PANI nanotubes (~90 nm and thermogravimetric analysis (TGA confirmed that the nanotubes were stable up to 230 °C. The PANI:PESA nanocomposite showed a quasi-reversible redox behaviour in phosphate buffer saline. Horseradish peroxidase (HRP was immobilized on to this modified electrode for hydrogen peroxide detection. The biosensor gave a sensitivity of 1.33 μA (μM-1 and a detection limit of 0.185 μM for H2O2. Stability experiments showed that the biosensor retained more than 64% of its initial sensitivity over four days of storage at 4 °C.

Effect Of Gamma Irradiation On The Chemical Properties Of Olive And Linseed Oils During The Storage Period

International Nuclear Information System (INIS)

Farag, M.D.H.; Eweida, M.H.T.; Ali, H.E.; Refai, K.M.

2013-01-01

The quality of edible oil is usually determined in term of its quality constants and the change in these constants would affect the quality of the oil. Evaluation of gamma irradiation and storage period effects on olive and linseed oils was studied. The studied changes in the chemical properties for these oils were free fatty acid, peroxide value, thiobarbituric acid, iodine value and saponification value. The applied irradiation doses were 4, 6 and 8 kGy while the dose rate was 3.529 kGy/h at the time of experimentation. The non-irradiated oil samples were used as controls. The irradiated oil samples showed that free fatty acid, peroxide value and thiobarbituric acid were increased and the iodine value was decreased with increasing the doses of radiation and storage period while the saponification value did not change by changing the applied radiation doses. The statistical analysis of the data exhibited that there were non-significant effects in irradiated oils during the storage period. However, the values of chemical properties of non-irradiated and irradiated oil samples were still within the normal limits of edible oils recommended by the Egyptian Standard Specifications (2005 a, b)

RANCIDITY DEVELOPMENT DURING FROZEN STORAGE OF FILLETS FROM GILTHEAD SEABREAM (Sparus aurata REARED IN ITALY

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P.P. Gatta

2013-02-01

Full Text Available Lipid oxidation indices (Free Fatty Acids-FFA, Peroxide Value-PV and Thiobarbituric Acid-TBA were evaluated in frozen fillets from seabream reared in Italy in: land based facilities (recirculation systems, lagoons or net-cages. Statistically significant differences emerged among seabream sources for all indices. Quality loss related to rancidity seemed to have been affected by both storage time and culturing system.

Lipid Peroxidation: Pathophysiology and Pharmacological Implications in the Eye

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Ya Fatou eNjie-Mbye

2013-12-01

Full Text Available Oxygen-derived free radicals such as hydroxyl and hydroperoxyl species have been shown to oxidize phospholipids and other membrane lipid components leading to lipid peroxidation. In the eye, lipid peroxidation has been reported to play an important role in degenerative ocular diseases (age-related macular degeneration, cataract, glaucoma, diabetic retinopathy. Indeed, ocular tissues are prone to damage from reactive oxygen species due to stress from constant exposure of the eye to sunlight, atmospheric oxygen and environmental chemicals. Furthermore, free radical catalyzed peroxidation of long chain polyunsaturated acids (LCPUFAs such as arachidonic acid and docosahexaenoic acid leads to generation of LCPUFA metabolites including isoprostanes and neuroprostanes that may further exert pharmacological/toxicological actions in ocular tissues. Evidence from literature supports the presence of endogenous defense mechanisms against reactive oxygen species in the eye, thereby presenting new avenues for the prevention and treatment of ocular degeneration. Hydrogen peroxide (H2O2 and synthetic peroxides can exert pharmacological and toxicological effects on tissues of the anterior uvea of several mammalian species. There is evidence suggesting that the retina, especially retinal ganglion cells can exhibit unique characteristics of antioxidant defense mechanisms. In the posterior segment of the eye, H2O2 and synthetic peroxides produce an inhibitory action on glutamate release (using [3H]-D-aspartate as a marker, in vitro and on the endogenous glutamate and glycine concentrations in vivo. In addition to peroxides, isoprostanes can elicit both excitatory and inhibitory effects on norepinephrine (NE release from sympathetic nerves in isolated mammalian iris ciliary bodies. Whereas isoprostanes attenuate dopamine release from mammalian neural retina, in vitro, these novel arachidonic acid metabolites exhibit a biphasic regulatory effect on glutamate release

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

Science.gov (United States)

Elikov, A V; Tsapok, P I

2010-01-01

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

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

Science.gov (United States)

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

2002-07-01

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

Plutonium(IV) peroxide formation in nitric medium and kinetics Pu(VI) reduction by hydrogen peroxide

International Nuclear Information System (INIS)

Maillard, C.; Adnet, J.M.

2001-01-01

Reduction of plutonium (VI) to Pu(IV) with hydrogen peroxide is a step in industrial processes used to purify plutonium nitrate solutions. This operation must be carefully controlled, in order to avoid any formation of the Pu(IV) peroxide green precipitate and to obtain exclusively Pu(IV). This led us to study the acidity and Pu and H 2 O 2 concentrations influences on the precipitate appearance and to perform a Pu(VI) reduction kinetic study on a wide range of acidities ([HNO 3 ]: 0.5 to 8 M), plutonium concentrations ([Pu(VI)]: 0.1 to 0.8 M) and [H 2 O 2 ]/[Pu(VI)] ratio (from 1 to 8). Thus, the domain of Pu(IV) peroxide formation and the reactional paths were established. With the exception of 0.5 M nitric acid medium, the kinetic curves show two distinct regims: the first one corresponds to an induction period where the Pu(VI) concentration doesn't change, the second corresponds to a linear decrease of Pu(VI). An increase of the temperature greatly accelerates the Pu(VI) reduction rate while [H 2 O 2 ]/[Pu(VI)] has almost no influence. The Pu(VI) total reduction time decreases when initial concentration of plutonium increases. By increasing nitric acid concentration from 0.5 M to 6 M, the total Pu(VI) reduction time decreases. This time increases when [HNO 3 ] varies from 6 M to 8 M. (orig.)

Ratiometric Sensing of Hydrogen Peroxide Utilizing Conformational Change in Fluorescent Boronic Acid Polymers

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Kan Takeshima

2017-01-01

Full Text Available We demonstrate that the copolymers containing boronic acid and pyrene units can be utilized for the fluorometric sensing of hydrogen peroxide (H2O2 in aqueous solutions. The copolymer exists in a relatively extended conformation in the absence of H2O2, whereas the polymer chain is contracted by the reaction of boronic acid moieties with H2O2 to form phenol groups. This conformational change induces aggregation of the originally isolated pyrene groups. As a result, relative intensity of excimer emission with respect to monomer emission increases with H2O2 concentration. Accordingly, the present methodology enables us to measure H2O2 by means of ratiometric fluorescence change in the range of 0–30 μM.

Changes in some physicochemical properties and fatty acid composition of irradiated meatballs during storage

Energy Technology Data Exchange (ETDEWEB)

Gecgel, U., E-mail: ugecgel@nku.edu.tr [Agricultural Faculty, Department of Food Engineering, Namik Kemal University, 59030 Tekirdag (Turkey)

2013-05-15

Meatball samples were irradiated using a {sup 60}Co irradiation source (with the dose of 1, 3, 5 and 7 kGy) and stored (1, 2 and 3 weeks at 4 Degree-Sign C) to appraise some physicochemical properties and the fatty acid composition. The physicochemical results showed no significant differences in moisture, protein, fat and ash content of meatballs because of irradiation. However, total acidity, peroxide and thiobarbituric acid (TBA) values increased significantly as a result of irradiation doses and storage period. The fatty acid profile in meatball samples changed with irradiation. While saturated fatty acids (C16:0, C17:0, C18:0, and C20:0) increased with irradiation, monounsaturated (C14:1, C15:1, C18:1, and C20:1) and polyunsaturated (C18:2, C18:3, and C22:2) fatty acids decreased with irradiation. Trans fatty acids (C16:1trans, C18:1trans, C18:2trans, C18:3trans) increased with increasing irradiation doses. Meatball samples irradiated at 7 kGy had the highest total trans fatty acid content. This research shows that some physicochemical properties and fatty acid composition of meatballs can be changed by gamma irradiation. (author)

Changes in some physicochemical properties and fatty acid composition of irradiated meatballs during storage.

Science.gov (United States)

Gecgel, Umit

2013-06-01

Meatball samples were irradiated using a (60)Co irradiation source (with the dose of 1, 3, 5 and 7 kGy) and stored (1, 2 and 3 weeks at 4°C) to appraise some physicochemical properties and the fatty acid composition. The physicochemical results showed no significant differences in moisture, protein, fat and ash content of meatballs because of irradiation. However, total acidity, peroxide and thiobarbituric acid (TBA) values increased significantly as a result of irradiation doses and storage period. The fatty acid profile in meatball samples changed with irradiation. While saturated fatty acids (C16:0, C17:0, C18:0, and C20:0) increased with irradiation, monounsaturated (C14:1, C15:1, C18:1, and C20:1) and polyunsaturated (C18:2, C18:3, and C22:2) fatty acids decreased with irradiation. Trans fatty acids (C16:1trans, C18:1trans, C18:2trans, C18:3trans) increased with increasing irradiation doses. Meatball samples irradiated at 7 kGy had the highest total trans fatty acid content. This research shows that some physicochemical properties and fatty acid composition of meatballs can be changed by gamma irradiation.

Changes in some physicochemical properties and fatty acid composition of irradiated meatballs during storage

International Nuclear Information System (INIS)

Gecgel, U.

2013-01-01

Meatball samples were irradiated using a 60 Co irradiation source (with the dose of 1, 3, 5 and 7 kGy) and stored (1, 2 and 3 weeks at 4 °C) to appraise some physicochemical properties and the fatty acid composition. The physicochemical results showed no significant differences in moisture, protein, fat and ash content of meatballs because of irradiation. However, total acidity, peroxide and thiobarbituric acid (TBA) values increased significantly as a result of irradiation doses and storage period. The fatty acid profile in meatball samples changed with irradiation. While saturated fatty acids (C16:0, C17:0, C18:0, and C20:0) increased with irradiation, monounsaturated (C14:1, C15:1, C18:1, and C20:1) and polyunsaturated (C18:2, C18:3, and C22:2) fatty acids decreased with irradiation. Trans fatty acids (C16:1trans, C18:1trans, C18:2trans, C18:3trans) increased with increasing irradiation doses. Meatball samples irradiated at 7 kGy had the highest total trans fatty acid content. This research shows that some physicochemical properties and fatty acid composition of meatballs can be changed by gamma irradiation. (author)

Lipid peroxidation and cytotoxicity induced by respirable volcanic ash

Energy Technology Data Exchange (ETDEWEB)

Cervini-Silva, Javiera, E-mail: jcervini@correo.cua.uam.mx [Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana Unidad Cuajimalpa, México City (Mexico); Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Nieto-Camacho, Antonio [Laboratorio de Pruebas Biológicas, Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, México City (Mexico); Gomez-Vidales, Virginia [Laboratorio de Resonancia Paramagnética Electrónica, Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, México City (Mexico); Ramirez-Apan, María Teresa [Laboratorio de Pruebas Biológicas, Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, México City (Mexico); Palacios, Eduardo; Montoya, Ascención [Dirección de Investigación y Posgrado, Instituto Mexicano del Petróleo (Mexico); Kaufhold, Stephan [BGR Bundesansaltfür Geowissenschaften und Rohstoffe, Stilleweg 2, D-30655 Hannover (Germany); and others

2014-06-01

Highlights: • Respirable volcanic ash induces oxidative degradation of lipids in cell membranes. • Respirable volcanic ash triggers cytotoxicity in murin monocyle/macrophage cells. • Oxidative stress is surface controlled but not restricted by surface- Fe{sup 3+}. • Surface Fe{sup 3+} acts as a stronger inductor in allophanes vs phyllosilicates or oxides. • Registered cell-viability values were as low as 68.5 ± 6.7%. - Abstract: This paper reports that the main component of respirable volcanic ash, allophane, induces lipid peroxidation (LP), the oxidative degradation of lipids in cell membranes, and cytotoxicity in murin monocyle/macrophage cells. Naturally-occurring allophane collected from New Zealand, Japan, and Ecuador was studied. The quantification of LP was conducted using the Thiobarbituric Acid Reactive Substances (TBARS) assay. The cytotoxic effect was determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide colorimetric assay. Electron-Paramagnetic Resonance (EPR) determinations of naturally-occurring allophane confirmed the incorporation in the structure and clustering of structural Fe{sup 3+}, and nucleation and growth of small-sized Fe (oxyhydr)oxide or gibbsite. LP induced by allophane varied with time, and solid concentration and composition, reaching 6.7 ± 0.2 nmol TBARS mg prot{sup −1}. LP was surface controlled but not restricted by structural or surface-bound Fe{sup 3+}, because redox processes induced by soluble components other than perferryl iron. The reactivity of Fe{sup 3+} soluble species stemming from surface-bound Fe{sup 3+} or small-sized Fe{sup 3+} refractory minerals in allophane surpassed that of structural Fe{sup 3+} located in tetrahedral or octahedral sites of phyllosilicates or bulk iron oxides. Desferrioxamine B mesylate salt (DFOB) or ethylenediaminetetraacetic acid (EDTA) inhibited LP. EDTA acted as a more effective inhibitor, explained by multiple electron transfer pathways. Registered cell

Effect of Copper on Fatty-Acid Composition and Peroxidation of Lipids in the Roots of Copper Tolerant and Sensitive Silene-Cucubalus.

NARCIS (Netherlands)

De Vos, C.H.R.; TenBookum, W.M.; Vooijs, R.; Schat, H.; De Kok, L.J.

1993-01-01

The effect of high copper exposure in vivo on the lipid and fatty acid composition and lipid peroxidation was studied in the roots of plants from one copper sensitive and two copper tolerant genotypes of Silene cucubalus. At 0.5 muM Cu (control treatment) the compositions of lipids and fatty acids

Selective Precipitation of Thorium lodate from a Tartaric Acid-Hydrogen Peroxide Medium Application to Rapid Spectrophotometric Determination of Thorium in Silicate Rocks and in Ores

Science.gov (United States)

Grimaldi, F.S.

1957-01-01

This paper presents a selective iodate separation of thorium from nitric acid medium containing d-tartaric acid and hydrogen peroxide. The catalytic decomposition of hydrogen peroxide is prevented by the use of 8quinolinol. A few micrograms of thorium are separated sufficiently clean from 30 mg. of such oxides as cerium, zirconium, titanium, niobium, tantalum, scandium, or iron with one iodate precipitation to allow an accurate determination of thorium with the thoronmesotartaric acid spectrophotometric method. The method is successful for the determination of 0.001% or more of thorium dioxide in silicate rocks and for 0.01% or more in black sand, monazite, thorite, thorianite, eschynite, euxenite, and zircon.

Protective effects of Sonchus asper against KBrO3 induced lipid peroxidation in rats.

Science.gov (United States)

Khan, Rahmat Ali; Khan, Muhammad Rashid; Sahreen, Sumaira

2012-11-27

Sonchus asper is traditionally used in Pakistan for the treatment of reproductive dysfunction and oxidative stress. The present investigation was aimed to evaluate chloroform extract of Sonchus asper (SACE) against potassium bromate-induced reproductive stress in male rats. 20 mg/kg body weight (b.w.) potassium bromate (KBrO3) was induced in 36 rats for four weeks and checked the protective efficacy of SACE at various hormonal imbalances, alteration of antioxidant enzymes, and DNA fragmentation levels. High performance chromatography (HPLC) was used for determination of bioactive constituents responsible. The level of hormonal secretion was significantly altered by potassium bromate. DNA fragmentation%, activity of antioxidant enzymes; catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) and phase II metabolizing enzymes viz; glutathione reductase (GSR), glutathione peroxidase (GSHpx), glutathione-S-tansase (GST) and reduced glutathione (GSH) was decreased while hydrogen per oxide contents and thiobarbituric acid reactive substances (TBARS) were increased with KBrO3 treatment. Treatment with SACE effectively ameliorated the alterations in the biochemical markers; hormonal and molecular levels while HPLC characterization revealed the presence of catechin, kaempferol, rutin and quercetin. Protective effects of Sonchus asper vs. KBrO3 induced lipid peroxidation might be due to bioactive compound present in SACE.

Protective effects of Sonchus asper against KBrO3 induced lipid peroxidation in rats

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Khan Rahmat Ali

2012-11-01

Full Text Available Abstract Background Sonchus asper is traditionally used in Pakistan for the treatment of reproductive dysfunction and oxidative stress. The present investigation was aimed to evaluate chloroform extract of Sonchus asper (SACE against potassium bromate-induced reproductive stress in male rats. Methods 20 mg/kg body weight (b.w. potassium bromate (KBrO3 was induced in 36 rats for four weeks and checked the protective efficacy of SACE at various hormonal imbalances, alteration of antioxidant enzymes, and DNA fragmentation levels. High performance chromatography (HPLC was used for determination of bioactive constituents responsible. Results The level of hormonal secretion was significantly altered by potassium bromate. DNA fragmentation%, activity of antioxidant enzymes; catalase (CAT, peroxidase (POD, superoxide dismutase (SOD and phase II metabolizing enzymes viz; glutathione reductase (GSR, glutathione peroxidase (GSHpx, glutathione-S-tansase (GST and reduced glutathione (GSH was decreased while hydrogen per oxide contents and thiobarbituric acid reactive substances (TBARS were increased with KBrO3 treatment. Treatment with SACE effectively ameliorated the alterations in the biochemical markers; hormonal and molecular levels while HPLC characterization revealed the presence of catechin, kaempferol, rutin and quercetin. Conclusion Protective effects of Sonchus asper vs. KBrO3 induced lipid peroxidation might be due to bioactive compound present in SACE.

Combined effects of temperature and metal exposure on the fatty acid composition of cell membranes, antioxidant enzyme activities and lipid peroxidation in yellow perch (Perca flavescens)

International Nuclear Information System (INIS)

Fadhlaoui, Mariem; Couture, Patrice

2016-01-01

Highlights: • The fatty acid composition of yellow perch muscle at 9 °C was enhanced in monounsaturated and polyunsaturated fatty acids compared to fish maintained at 28 °C. • The thermal adjustment of muscle phospholipid fatty acid profiles is likely due to modifications of desaturase and elongase activities. • Exposure to Ni and Cd modified muscle phospholipid fatty acid composition in a temperature-dependent manner. • The higher fatty polyinsaturation in cold-acclimated fish did not increase their vulnerability to peroxidation. • Lower concentrations of malondialdehyde were measured in warm-acclimated, Ni-exposed fish, suggesting an overcompensation of antioxidant mechanisms that could explain their lower condition. - Abstract: The aim of this study was to investigate the combined effects of temperature and metal contamination (cadmium and nickel) on phospholipid fatty acid composition, antioxidant enzyme activities and lipid peroxidation in fish. Yellow perch were acclimated to two different temperatures (9 °C and 28 °C) and exposed either to Cd or Ni (respectively 4 μg/L and 600 μg/L) for seven weeks. Superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase activities and glutathione concentration were measured as indicators of antioxidant capacities, while malondialdehyde concentration was used as an indicator of lipid peroxidation. Poikilotherms including fish counteract the effects of temperature on phospholipid fatty acid ordering by remodelling their composition to maintain optimal fluidity. Accordingly, in our study, the fatty acid composition of yellow perch muscle at 9 °C was enhanced in monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) compared to fish maintained at 28 °C, in agreement with the theory of homeoviscous adaptation. Using ratios of various fatty acids as surrogates for desaturase and elongase activities, our data suggests that modification of the activity of these enzymes is

Combined effects of temperature and metal exposure on the fatty acid composition of cell membranes, antioxidant enzyme activities and lipid peroxidation in yellow perch (Perca flavescens)

Energy Technology Data Exchange (ETDEWEB)

Fadhlaoui, Mariem; Couture, Patrice, E-mail: patrice.couture@ete.inrs.ca

2016-11-15

Highlights: • The fatty acid composition of yellow perch muscle at 9 °C was enhanced in monounsaturated and polyunsaturated fatty acids compared to fish maintained at 28 °C. • The thermal adjustment of muscle phospholipid fatty acid profiles is likely due to modifications of desaturase and elongase activities. • Exposure to Ni and Cd modified muscle phospholipid fatty acid composition in a temperature-dependent manner. • The higher fatty polyinsaturation in cold-acclimated fish did not increase their vulnerability to peroxidation. • Lower concentrations of malondialdehyde were measured in warm-acclimated, Ni-exposed fish, suggesting an overcompensation of antioxidant mechanisms that could explain their lower condition. - Abstract: The aim of this study was to investigate the combined effects of temperature and metal contamination (cadmium and nickel) on phospholipid fatty acid composition, antioxidant enzyme activities and lipid peroxidation in fish. Yellow perch were acclimated to two different temperatures (9 °C and 28 °C) and exposed either to Cd or Ni (respectively 4 μg/L and 600 μg/L) for seven weeks. Superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase activities and glutathione concentration were measured as indicators of antioxidant capacities, while malondialdehyde concentration was used as an indicator of lipid peroxidation. Poikilotherms including fish counteract the effects of temperature on phospholipid fatty acid ordering by remodelling their composition to maintain optimal fluidity. Accordingly, in our study, the fatty acid composition of yellow perch muscle at 9 °C was enhanced in monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) compared to fish maintained at 28 °C, in agreement with the theory of homeoviscous adaptation. Using ratios of various fatty acids as surrogates for desaturase and elongase activities, our data suggests that modification of the activity of these enzymes is

チオバルビツール酸法による血清過酸化脂質の測定：比色法と蛍光法の比較並びに二価鉄の影響

OpenAIRE

山本, 剛禧

1992-01-01

Serum lipid peroxides were measured by a thiobarbituric acid (TBA) method. TBA color reactions carried out under the conditions with acetic acid (TBA-AA) or hydrochloric acid (TBA-HCl) systems, and then TBA value was detected by colorimetric ([OD]) and fluorometric ([FR]) measurements. Effects of ferrous ion, ferric ion and EDTA on the both systems were examined. Equal TBA value dependent upon concentrations of MDA (tetraethoxypropane) were obtained on both systems detected by [OD], but the r...

Sun-drying diminishes the antioxidative potentials of leaves of Eugenia uniflora against formation of thiobarbituric acid reactive substances induced in homogenates of rat brain and liver.

Science.gov (United States)

Kade, Ige Joseph; Ibukun, Emmanuel Oluwafemi; Nogueira, Cristina Wayne; da Rocha, Joao Batista Teixeira

2008-08-01

Extracts from leaves of Pitanga cherry (Eugenia uniflora) are considered to be effective against many diseases, and are therefore used in popular traditional medicines. In the present study, the antioxidative effect of sun-dried (PCS) and air-dried (PCA) ethanolic extracts of Pitanga cherry leaves were investigated. The antioxidant effects were tested by measuring the ability of both PCS and PCA to inhibit the formation of thiobarbituric acid reactive species (TBARS) induced by prooxidant agents such as iron (II) and sodium nitroprusside (SNP) in rat brain and liver tissues. The results showed that while PCA significantly (P<0.0001) inhibited the formation of TBARS in both liver and brain tissues homogenates, PCS did not. Further investigation reveals that the phenolic content of the PCS was significantly (P<0.0001) lower compared to PCA. Since phenolics in plants largely contributed to the antioxidative potency of plants, we conclude that air-drying should be employed in the preparation of extracts of Pitanga cherry leaves before it is administered empirically as a traditional medicament, and hence this study serves a public awareness to traditional medical practitioners.

Lipid Peroxidation and Electrolytes in Irradiated Rats Treated with Caffeine

International Nuclear Information System (INIS)

Abdel-Gawad, I.I.; Ahmed, A.M.

2005-01-01

This Study was conducted to elarify the potential role of caffeine (1,3,7-trimethyl xanthine), a major component of coffee, against damages induced by gamma rays. Thirty adult female albino rats (130+10) were divided into three groups, each of ten animals. The first group acted as control animals. The second was sujected to a single dose of (7) Gy whole body gamma irradiation. The third group was injected intraperitoneally with a single dose (80mg/kg body weight) of caffeine one-hour prior irradiation. Blood samples were collected five time intervals 1,3,7,15 and 30 days post-irradiation. The content of serum lipid peroxides was measured as thiobarbituric acid reactive substance (TBARS). Electrolytes as calcium (Ca2 + ), sodium (Na + ) and potassium (K + ) and levels were estimated and Na + /K + ratio was calculated. Also serum enzymes as alkaline phosphatase (ALP) and aminotransaminases (AST and ALT) activity levels were measured. The data revealed significant increase in TBARS, AST and ALT levels in serum due to irradiation exposure. While, radiation induced significant decrease in serum level of ALP, level of electrolytes Ca 2+ , Ma + , and Na + /K + ratio. On the other hand, group injected intraperitoneally with caffeine pre-irradiation exhibited reduction in the changes produced by gamma-radiation with variable degree. The data showed that this antioxidant confers protection damage inflicted by radiation when given prior to irradiation exposure on the examined parameters

Comparison of the antioxidant effects of carnosic acid and synthetic antioxidants on tara seed oil.

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Li, Zhan-Jun; Yang, Feng-Jian; Yang, Lei; Zu, Yuan-Gang

2018-04-04

In the present study, tara seed oil was obtained by supercritical fluid extraction and used to investigate the antioxidant strength of carnosic acid (CA) compared with conventional synthetic antioxidants. The antioxidants were added to the tara seed oil at 0.2 mg of antioxidant per gram of oil. The samples were then submitted to at 60 °C 15 days for an accelerated oxidation process, with samples taken regularly for analysis. After oxidation, the samples were analyzed to determine the peroxide value, thiobarbituric acid reactive substances, conjugated diene content, and free fatty acid content. CA was investigated at three purity levels (CA20, CA60, CA99), and compared with three synthetic antioxidants (butylatedhydroxyanisole, butylatedhydroxytoluene, and tert-butylhydroquinone). The oxidation indicators showed that CA was a strong antioxidant compared to the synthetic antioxidants. The antioxidant activities decreased in the order: tert-butylhydroquinone > CA99 > CA60 > CA20 > butylatedhydroxyanisole > butylatedhydroxytoluene. These results show that CA could be used to replace synthetic antioxidants in oil products, and should be safer for human consumption and the environment.

The omega-3 fatty acid DHA dose-dependently reduces atherosclerosis: a putative role for F4-neuroprostanes a specific class of peroxidized metabolites

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Objective. Consumption of long chain omega-3 polyunsaturated fatty acids is associated with reduced risks of cardiovascular disease but the role of their oxygenated metabolites remains unclear. We hypothesized that peroxidized metabolites of docosahexaenoic acid (DHA, 22:6 n-3) could play a role in ...

UV-C photolysis of endocrine disruptors. The influence of inorganic peroxides

International Nuclear Information System (INIS)

Rivas, Javier; Gimeno, Olga; Borralho, Teresa; Carbajo, Maria

2010-01-01

Norfloxacin, doxycycline and mefenamic acid have been photolysed with UV-C radiation (254 nm) in the presence and absence of inorganic peroxides (hydrogen peroxide or sodium monopersulfate). Quantum yields in the range (1.1-4.5) x 10 -3 mol Einstein -1 indicate the low photo-reactivity of these pharmaceuticals. Inorganic peroxides considerably enhanced the contaminants conversion, although no appreciable mineralization could be obtained. A simplistic reaction mechanism for the hydrogen peroxide promoted experiments allowed for a rough estimation of the rate constant between hydroxyl radicals and norfloxacin (k > 1 x 10 9 M -1 s -1 ), doxycycline (k > 1.5 x 10 9 M -1 s -1 ) and mefenamic acid (k > 11.0 x 10 9 M -1 s -1 ).

Studies on antibacterial activity of ZnO nanoparticles by ROS induced lipid peroxidation.

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Dutta, R K; Nenavathu, Bhavani P; Gangishetty, Mahesh K; Reddy, A V R

2012-06-01

Recent studies indicated the role of ROS toward antibacterial activity. In our study we report ROS mediated membrane lipid oxidation of Escherichia coli treated with ZnO nanoparticles (NPs) as supported by detection and spectrophotometric measurement of malondialdehyde (MDA) by TBARS (thiobarbituric acid-reactive species) assay. The antibacterial effects of ZnO NPs were studied by measuring the growth curve of E. coli, which showed concentration dependent bacteriostatic and bacteriocidal effects of ZnO NPs. The antibacterial effects were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Further, antibacterial effect of ZnO NPs was found to decrease by introducing histidine to the culture medium treated with ZnO NPs. The ROS scavenging action of histidine was confirmed by treating histidine to the batch of Escherichia coli+ZnO NPs at the end of the lag phase of the growth curve (Set-I) and during inoculation (Set-II). A moderate bacteriostatic effect (lag in the E. coli growth) was observed in Set-II batch while Set-I showed no bacteriostatic effect. From these evidences we confirmed that the antibacterial effect of bare as well as TG capped ZnO NPs were due to membrane lipid peroxidation caused by the ROS generated during ZnO NPs interaction in culture medium. Copyright © 2012 Elsevier B.V. All rights reserved.

Hippocampus lipid peroxidation induced by residual oil fly ash intranasal instillation versus habituation to the open field.

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Zanchi, Ana Claudia; Saiki, Mitiko; Saldiva, Paulo Hilário Nascimento; Barros, Helena Maria Tannhauser; Rhoden, Claudia Ramos

2010-01-01

Epidemiological studies have demonstrated the adverse effects of particulate matter (PM) inhalation on the respiratory and cardiovascular systems. It has been reported that air pollution may affect the central nervous system and decrease cognitive function. In rats, residual oil fly ash (ROFA) instillation causes decreased motor activity and increased lipid peroxidation in the striatum and the cerebellum. Our objective was to determine whether chronic instillation of particles induces changes in learning and memory in rats and whether oxidants in the hippocampus may contribute to these adverse effects. Forty-five-day-old male Wistar rats were exposed to ROFA by intranasal instillation and were treated with N-acetylcysteine (NAC) at 150 mg/kg i.p. for 30 days. Control groups were exposed to ROFA, NAC, or neither. On days 1, 8, and 30 of the protocol, rats were submitted to the open field test to evaluate habituation. After the last open field session, the rats were killed by decapitation. The hippocampus was used to determine lipid peroxidation (LP) by the thiobarbituric acid-reactive substances test. ROFA instillation induced an increase in LP in the hippocampus compared to all treatment groups (p = .012). NAC treatment blocked these changes. All of the treatment groups presented a decrease in the frequency of peripheral walking (p = .001), rearing (p = .001), and exploration (p = .001) over time. Our study demonstrates that exposure to particles for 30 days and/or NAC treatment do not modify habituation to an open field, a simple form of learning and memory in rats, and that oxidative damage induced by ROFA does not modulate these processes.

Oxidative stress and antioxidant status in beta-thalassemia heterozygotes

Directory of Open Access Journals (Sweden)

Luciana de Souza Ondei

2013-01-01

Full Text Available Background: Several studies have evaluated the oxidant and antioxidant status of thalassemia patients but most focused mainly on the severe and intermediate states of the disease. Moreover, the oxidative status has not been evaluated for the different beta-thalassemia mutations. Objective: To evaluate lipid peroxidation and Trolox equivalent antioxidant capacity in relation to serum iron and ferritin in beta thalassemia resulting from two different mutations (CD39 and IVS-I-110 compared to individuals without beta-thalassemia. Methods: One hundred and thirty subjects were studied, including 49 who were heterozygous for beta-thalassemia and 81 controls. Blood samples were subjected to screening tests for hemoglobin. Allele-specific polymerase chain reaction was used to confirm mutations for beta-thalassemia, an analysis of thiobarbituric acid reactive species was used to determine lipid peroxidation, and Trolox equivalent antioxidant capacity evaluations were performed. The heterozygous beta-thalassemia group was also evaluated for serum iron and ferritin status. Results: Thiobarbituric acid reactive species (486.24 ± 119.64 ng/mL and Trolox equivalent antioxidant capacity values (2.23 ± 0.11 mM/L were higher in beta-thalassemia heterozygotes compared to controls (260.86 ± 92.40 ng/mL and 2.12 ± 0.10 mM/L, respectively; p-value < 0.01. Increased thiobarbituric acid reactive species values were observed in subjects with the CD39 mutation compared with those with the IVS-I-110 mutation (529.94 ± 115.60 ng/mL and 453.39 ± 121.10 ng/mL, respectively; p-value = 0.04. However, average Trolox equivalent antioxidant capacity values were similar for both mutations (2.20 ± 0.08 mM/L and 2.23 ± 0.12 mM/L, respectively; p-value = 0.39. There was no influence of serum iron and ferritin levels on thiobarbituric acid reactive species and Trolox equivalent antioxidant capacity values. Conclusion: This study shows an increase of oxidative stress and

Albumin-bound fatty acids but not albumin itself alter redox balance in tubular epithelial cells and induce a peroxide-mediated redox-sensitive apoptosis

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Ruggiero, Christine; Elks, Carrie M.; Kruger, Claudia; Cleland, Ellen; Addison, Kaity; Noland, Robert C.

2014-01-01

Albuminuria is associated with metabolic syndrome and diabetes. It correlates with the progression of chronic kidney disease, particularly with tubular atrophy. The fatty acid load on albumin significantly increases in obesity, presenting a proinflammatory environment to the proximal tubules. However, little is known about changes in the redox milieu during fatty acid overload and how redox-sensitive mechanisms mediate cell death. Here, we show that albumin with fatty acid impurities or conjugated with palmitate but not albumin itself compromised mitochondrial and cell viability, membrane potential and respiration. Fatty acid overload led to a redox imbalance which deactivated the antioxidant protein peroxiredoxin 2 and caused a peroxide-mediated apoptosis through the redox-sensitive pJNK/caspase-3 pathway. Transfection of tubular cells with peroxiredoxin 2 was protective and mitigated apoptosis. Mitochondrial fatty acid entry and ceramide synthesis modulators suggested that mitochondrial β oxidation but not ceramide synthesis may modulate lipotoxic effects on tubular cell survival. These results suggest that albumin overloaded with fatty acids but not albumin itself changes the redox environment in the tubules, inducing a peroxide-mediated redox-sensitive apoptosis. Thus, mitigating circulating fatty acid levels may be an important factor in both preserving redox balance and preventing tubular cell damage in proteinuric diseases. PMID:24500687

Oxidative stress biomarkers in different tissues of rainbow trout (Oncorhynchus mykiss exposed to Disinfectant-CIP formulated with peracetic acid and hydrogen peroxide

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Tkachenko Halyna

2014-09-01

Full Text Available The aim of study was to determine the effects of exposure to the product DEZYNFEKTANT-CIP (Eng. - Disinfectant-CIP, which is formulated with peracetic acid and hydrogen peroxide, on oxidative stress biomarkers (lipid peroxidation (LPO levels and the carbonyl content of oxidatively modified proteins and antioxidant defenses (superoxide dismutase (SOD, catalase (CAT, glutathione reductase (GR, glutathione peroxidase (GPx, total antioxidant capacity in muscle, gill, hepatic, and cardiac tissues of rainbow trout, Oncorhynchus mykiss (Walbaum. LPO and carbonyl contents changed with tissue type. Exposure to Disinfectant-CIP led to a significant decrease in LPO in muscle tissues and carbonyl content in muscle and gill tissues. The inhibition of SOD and CAT activity in muscle, hepatic, and cardiac tissues was observed probably because of increased oxidative stress during disinfection; however, hepatic and cardiac GPx activity increased in an attempt to counteract oxidative stress. We suggest that oxidative stress during the oxidation of peracetic acid and hydrogen peroxide could be counteracted by the antioxidant system in trout tissues. Correlative analysis between oxidative stress biomarkers and antioxidant defense confirms the pivotal role of SOD and CAT against CIP-induced oxidative stress

Leaching of metals from large pieces of printed circuit boards using citric acid and hydrogen peroxide.

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Jadhav, Umesh; Su, C; Hocheng, Hong

2016-12-01

In the present study, the leaching of metals from large pieces of computer printed circuit boards (CPCBs) was studied. A combination of citric acid (0.5 M) and 1.76 M hydrogen peroxide (H 2 O 2 ) was used to leach the metals from CPCB piece. The influence of system variables such as H 2 O 2 concentration, concentration of citric acid, shaking speed, and temperature on the metal leaching process was investigated. The complete metal leaching was achieved in 4 h from a 4 × 4 cm CPCB piece. The presence of citric acid and H 2 O 2 together in the leaching solution is essential for complete metal leaching. The optimum addition amount of H 2 O 2 was 5.83 %. The citric acid concentration and shaking speed had an insignificant effect on the leaching of metals. The increase in the temperature above 30 °C showed a drastic effect on metal leaching process.

Leaching of a Cu-Co ore from Congo using sulphuric acidhydrogen peroxide leachants

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Seo S.Y.

2013-01-01

Full Text Available A Cu-Co ore from Katinga Province, the Republic of Congo containing 1.5% Co and 1.6% Cu was tested to determine the leachability of Cu and Co using sulphuric acid and hydrogen peroxide mixtures at different conditions. Without hydrogen peroxide, the maximum extraction of copper and cobalt were found to be ~80% and ~15%, respectively when the acid concentration was varied between 0.36 - 1.1M. When hydrogen peroxide was added (0.008-0.042M, Cu recovery was enhanced to ~90%. Recoveries of ~90% of Co could be achieved at 20ºC, using leachants consisting of 0.36M sulphuric acid and 0.025M hydrogen peroxide after 3 hours. The reaction time to reach 90% Co extraction was reduced to less than 2 hours at 30ºC. Stabcal modelling of the Eh-pH diagrams shows the importance of hydrogen peroxide as a reductant. The decrease of solution potential (300-350 mV by adding hydrogen peroxide was confirmed by Eh measurements during the tests. The leaching follows the shrinking core model kinetics, where the rate constant is linearly dependent on hydrogen peroxide concentration in the range 0-0.025M and proportional to (1/r2 where r is the average radius of the mineral particles. The activation energy for the leaching process is 72.3 kJ/mol.

Can aqueous hydrogen peroxide be used as a stand-alone energy source?

International Nuclear Information System (INIS)

Disselkamp, Robert S.

2010-01-01

A novel electrochemical scheme to convert a stand-alone supply of aqueous hydrogen peroxide into a fuel cell-ready stream of hydrogen gas plus aqueous hydrogen peroxide is described. The electrochemical cell, consisting of a solid base and solid acid electrocatalyst, together with a proton exchange membrane, comprise the system that converts aqueous hydrogen peroxide into separate gas streams of oxygen and hydrogen. Aqueous hydrogen peroxide is contained in the anode compartment only and exists in the region where oxygen gas is formed, whereas the cathode compartment is where hydrogen gas is generated and therefore exists in a reduced state. A near zero theoretical over-potential can be achieved by the choice of basicity and acidity of the electrode materials. The primary cost of the electrochemical cell is electrode construction and the aqueous hydrogen peroxide energy storage compound. Additional research effort is required to experimentally validate the concept and explore the full economic impact should initial studies, based on the design presented here, prove promising. (author)

Studies on the lipid peroxidation in mitochondria of x-ray whole-body irradiated rat liver, 2

International Nuclear Information System (INIS)

Wakabayashi, Hiroshi

1976-01-01

The results of investigation made on the mitochondria of rat liver on the 3rd day after irradiation of 650 R are as follows: After lipid peroxidation, the mitochondria showed a decrease of polyenoic acids (C-20:4, C-22:6) suggesting that polyenoic acids are the substrate of the reaction. Unsaturated fatty acids were decreased due to the decrement of C-18:1 and C-18:2, and polyenoic acid was relatively increased. These changes were transient, reaching a maximum on the 3rd day after irradiation. The rate of peroxidation in total lipids extracted form normal mitochondria was the same as that from whole-body irradiated mitochondria. There was no lag in the induction period in either reaction. Marked peroxidation of the total lipid was seen in the phospholipid fraction and slight peroxidation in the simple lipid fractions. No significant effect of whole-body irradiation on the peroxidation activities of the phospholipid was observed. With thin-layer chromatography, peroxidation of subfractionated phospholipid showed marked activity in the lecithin and aminophosphatide fractions containing large amounts of C-20:4 and C-22.6. Recovery of activity in the subfractions was greater than that in the total phospholipid. The effect of whole-body irradiation appeared to be significant in these subfractions. However no relationships could be seen between the activities peroxidation and the fatty acid composition of the subfractions. The ratio of phospholipid to total lipid increased in whole-body irradiated samples. From these findings there was a discussion of whether or not Fe ++ -induced lipid peroxidation at the mitochondrial level is due to change in the composition of fatty acid and the association of lipid in the membrane. (Evans, J.)

Effects of whole-body γ-irradiation on lipid peroxidation and anti-oxidant enzymes in the liver of N-nitrosodiethylamine-treated mice

International Nuclear Information System (INIS)

Grudzinski, I.P.; Frankiewicz-Jozko, A; Gajewska, J.; Szczypka, M.; Szymanski, A.

2000-01-01

B6c3F1 mice were treated per os with either normal saline or N-nitrosodiethylamine (NDEA) (0.01, 0.1, 1.0 or 5.0 mg/kg body weight) daily for 21 days. On day 22 nd of the experiment , the animals were whole-body γ-irradiated (10 Gy) and examined at 3.5 days post-radiation exposure. Pretreatment of mice with NDEA at the lowest dosage (0.01 and 0.1 mg/kg) increased thiobarbituric acid-reactive substances (TBARS) and catalase (CAT) activity in the liver. Since the agent at the highest doses (1.0 and 5.0 mg/kg) did not have any effects on TBARS, it was associated with the selective increase of thiol (SH) groups and GSH-linked anti-oxidant enzyme activities such as glutathione peroxidase (GPX), transferase (GST) and reductase (GR). γ-irradiation decreased TBARS and increased superoxide dismutase (SOD) and GPX activity in NDEA-treated mice. Simultaneously, γ-rays did not have any effects on GST and GR enzymes, and it slightly decreased SH groups and CAT activity. Results of the present study indicate that NDEA can promote lipid peroxidation in mice liver. γ-irradiation of mice at a dose of 10 Gy modifies the activity of hepatic anti-oxidant enzymes, which in turn can lead to the reduction of NDEA-induced lipid peroxidation and/or pro-oxidant shift(s). The anti-oxidant enzymes such as SOD and GPX are suggested to be mainly involved in this process. (author)

Ischaemic preconditioning attenuates haemodynamic response and lipid peroxidation in lower-extremity surgery with unilateral pneumatic tourniquet application: a clinical pilot study.

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Van, Mukaddes; Olguner, Cimen; Koca, Uğur; Sişman, Ali Riza; Muratli, Kivanç; Karci, Ayşe; Mavioğlu, Omür; Kilercik, Hakan

2008-04-01

The harmful effects of ischaemia-reperfusion on skeletal muscle during extremity surgery can be diminished by using medications or ischaemic preconditioning Twenty patients undergoing lower-limb surgery with use of a tourniquet for at least 1 hour were included in the study and randomised into two groups: a control group with only tourniquet application (T group; n=10); and an ischaemic preconditioning plus tourniquet group (IP-T group; n=10). Blood samples were obtained from the femoral vein of the relevant extremity before tourniquet application (baseline), immediately after tourniquet deflation (TD), at 10 minutes after the tourniquet deflation (TD(10min)) in the T group and additionally after ischaemic preconditioning in the IP-T group. Venous blood pH, partial oxygen pressure (P(vO2)), partial carbon dioxide pressure (P(vCO2)), lactate, potassium, sodium and glucose levels were analysed using a blood gas analyser. Plasma thiobarbituric acid reactive substances (TBARS) level, an index of lipid peroxidation and oxidative stress, was measured. Heart rate, noninvasive mean arterial pressure (MAP) and spontaneous breathing rate (SBR) were recorded at baseline, at TD, and TD(1min), TD(5min) and TD(10min). MAP decreased and SBR increased significantly at TD, TD(1min) and TD(5min) compared with baseline, and venous blood TBARS level significantly increased at TD and TD(10min) compared with baseline in the T group (all Plactate levels, which was significant compared with baseline (P<0.05) Ischaemic preconditioning attenuates haemodynamic response and lipid peroxidation during lower-extremity surgery with unilateral tourniquet application.

Dissolution of oxalate precipitate and destruction of oxalate ion by hydrogen peroxide in nitric acid solution

International Nuclear Information System (INIS)

Kim, Eung-Ho; Chung, Dong-Yong; Park, Jin-Ho; Yoo, Jae-Hyung

2000-01-01

This study aims at developing an oxalate precipitation process, which is applicable to a partitioning of long-lived radionuclides from the high-level radioactive liquid waste. In order to achieve this, a study for decomposition-reaction of oxalic acid by hydrogen peroxide was first carried out. The decomposition rates of H 2 O 2 and oxalic acid increased with an increase of nitric acid concentration, and especially those decomposition rates steeply increased at more than 2 M HNO 3 . Based on this result, the decomposition kinetics of H 2 O 2 and oxalic acid were suggested in this work. Then, the dissolution of oxalate precipitate and the destruction of oxalate ion in the solution were examined. Oxalate precipitates were prepared by adding oxalic acid into a simulated radioactive waste containing 8 metallic elements. The precipitates obtained thereby were dissolved in various nitric acid concentrations and reacted with H 2 O 2 at 90degC. When the oxalates were completely dissolved, most of the oxalates were decomposed by adding H 2 O 2 , but in a slurry state the decomposition yield of the oxalate decreased with an increase of the slurry density in the solution. Such phenomenon was considered to be due to a catalytic decomposition of H 2 O 2 on a solid surface of oxalate and the decomposition mechanism was explained by a charge transfer from a surface of oxalate solid to H 2 O 2 , producing OH radicals which can destruct H 2 O 2 explosively. Accordingly, the experimental condition for the decomposition of the oxalate precipitates was found to be most favorable at 3 M HNO 3 under the initial concentrations of 0.2 M oxalate and 1 M H 2 O 2 . At 3M HNO 3 , oxalate precipitates could be safely and completely dissolved, and almost decomposed. Additionally, it was observed that the presence of ferric ion in the solution largely affects the decomposition rate of H 2 O 2 . This could be explained by a chain reaction of hydrogen peroxide with ferric ion in the solution

Inhibition of radiation-induced lipid peroxidation by means of gallic polydisulphide

International Nuclear Information System (INIS)

Losev, Yu.P.; Amadyan, M.G.; Oganesyan, N.M.; Fedulov, A.S.; Abramyan, A.K.; Shagoyan, A.G.; Khachkavanktsyan, A.S.

1999-01-01

Inhibition of radiation-induced lipid peroxidation by means of gallic polydisulphade has been studied. Rats were exposed to X-rays in doses 4,8 and 5,25 Gy. Lipid peroxidation was analysed in blood plasma, membranes of erythrocytes and homogenates of liver and spleen tissues of rats. Polydisulphide of gallic acid was used as inhibitor of lipid peroxidation because of its effective antioxidant properties as have been reported previously. It has been demonstrated that gallic disulphide exhibited high inhibition efficiency in conditions of radiation-induced lipid peroxidation due to the effect of intra-molecular synergism

A SIFT Study of the Reactions of H3O+, NO+ and O2+ with Hydrogen Peroxide and Peroxyacetic Acid

Czech Academy of Sciences Publication Activity Database

Španěl, Patrik; Diskin, A. M.; Wang, T.; Smith, D.

2003-01-01

Roč. 228, - (2003), s. 269-283 ISSN 1387-3806 R&D Projects: GA ČR GA202/03/0827; GA ČR GA203/02/0737 Institutional research plan: CEZ:AV0Z4040901 Keywords : SIFT * hydrogen peroxide * peroxyacetic acid Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.361, year: 2003

Determination of active oxygen content in rare earth peroxides

International Nuclear Information System (INIS)

Queiroz, Carlos A.S.; Abrao, Alcidio

1993-01-01

The content of active oxygen in rare earth peroxides have been determined after the dissolution of the samples with hydrocloridic acid in the presence of potassium iodide. The free generated iodine is titrated with sodium thiosulfate using starch as indicator. The oxidation of iodide to the free iodine indicates the presence of a higher valence state rare earth oxide, until now specifically recognized for the oxides of cerium (Ce O 2 ), praseodymium (Pr 6 O 1 1) and terbium (TB 4 O 7 ). recently the authors synthesized a new series of rare earth compounds, the peroxides. These new compounds were prepared by precipitating the rare earth elements complexed with carbonate ion by addition of hydrogen peroxide. the authors demonstrated that all rare earth elements, once solubilized by complexing with carbonate ion, are quantitatively precipitated as peroxide by addition of hydrogen peroxide. (author)

Effects of vitamin E and selenium supplementation on blood lipid peroxidation and cortisol concentration in dairy cows undergoing omentopexy.

Science.gov (United States)

Mudron, P; Rehage, J

2018-04-11

Twenty dairy cows with left abomasal displacement were used to investigate the effects of vitamin E and selenium treatment on thiobarbituric acid reactive substances (TBARS) and blood cortisol in dairy cows stressed by omentopexy. The cows were randomly divided into two groups. Ten hours before surgery 6 g of DL-α-tocopheryl acetate (6 mg/kg) and 67 mg of natrium selenite (0.1 mg/kg) in volume of 40 ml (Vitaselen ® ) were administered subcutaneously to 10 cows; the control animals (n = 10) received an equivalent volume of injectable water (40 ml). The injection of vitamin E and selenium produced a rapid rise (p E increased several times 10 hr after vitamin E and Se injection and raised continuously to the highest average concentration 21.6 mg/L at hr 24 after the surgery. The highest selenium concentration was seen 10 hr after selenium administration with holding the increased concentrations in comparison with initial ones during the whole study. Two-way ANOVA did not show significant treatment effect on plasma concentrations TBARS in the study. The plasma concentrations of thiobarbituric acid reactive substances reached the maximum value of 0.18 μmol/L in the control group 5 hr after the surgery. Twenty-four hours after the surgery, the TBARS values returned to the initial ones. Serum cortisol increased in both groups after surgery. The highest cortisol concentrations were reached at 1 hr after surgery in the experimental and control group (56.7 ± 28.8 and 65.3 ± 26.1 μg/L respectively). A return to the levels similar to the initial ones was recognized 24 hr after the surgery. The ANOVA revealed a significant effect of vitamin E and selenium injection on plasma cortisol (p E/Se injection on blood lipid peroxidation. In addition, a weaker cortisol response to the abdominal surgery was recognized in animals treated with vitamin E and selenium. © 2018 Blackwell Verlag GmbH.

Region-specific vulnerability to lipid peroxidation and evidence of neuronal mechanisms for polyunsaturated fatty acid biosynthesis in the healthy adult human central nervous system.

Science.gov (United States)

Naudí, Alba; Cabré, Rosanna; Dominguez-Gonzalez, Mayelin; Ayala, Victoria; Jové, Mariona; Mota-Martorell, Natalia; Piñol-Ripoll, Gerard; Gil-Villar, Maria Pilar; Rué, Montserrat; Portero-Otín, Manuel; Ferrer, Isidre; Pamplona, Reinald

2017-05-01

Lipids played a determinant role in the evolution of the brain. It is postulated that the morphological and functional diversity among neural cells of the human central nervous system (CNS) is projected and achieved through the expression of particular lipid profiles. The present study was designed to evaluate the differential vulnerability to oxidative stress mediated by lipids through a cross-regional comparative approach. To this end, we compared 12 different regions of CNS of healthy adult subjects, and the fatty acid profile and vulnerability to lipid peroxidation, were determined by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS), respectively. In addition, different components involved in PUFA biosynthesis, as well as adaptive defense mechanisms against lipid peroxidation, were also measured by western blot and immunohistochemistry, respectively. We found that: i) four fatty acids (18.1n-9, 22:6n-3, 20:1n-9, and 18:0) are significant discriminators among CNS regions; ii) these differential fatty acid profiles generate a differential selective neural vulnerability (expressed by the peroxidizability index); iii) the cross-regional differences for the fatty acid profiles follow a caudal-cranial gradient which is directly related to changes in the biosynthesis pathways which can be ascribed to neuronal cells; and iv) the higher the peroxidizability index for a given human brain region, the lower concentration of the protein damage markers, likely supported by the presence of adaptive antioxidant mechanisms. In conclusion, our results suggest that there is a region-specific vulnerability to lipid peroxidation and offer evidence of neuronal mechanisms for polyunsaturated fatty acid biosynthesis in the human central nervous system. Copyright © 2017 Elsevier B.V. All rights reserved.

Studies on the physicochemical characteristics of oil extracted from gamma irradiated pistachio (Pistacia vera L.).

Science.gov (United States)

Al-Bachir, Mahfouz

2015-01-15

The present study evaluated the quality of pistachio oil, as a function of irradiation, to determine the dose level causing undesirable changes to pistachio oil. Physicochemical fatty acid composition, acidity value, peroxide value, iodine value specification number, thiobarbituric acid (TBA) value and colour of pistachio oil extracted from samples treated with 0, 1, 2 and 3 kGy doses of gamma irradiation were determined. Gamma irradiation caused the alteration of fatty acids of pistachio oil which showed a decrease in oleic acid (C18:1) and an increase in linoleic acid (C18:2). All other fatty acids remained unaffected after irradiation. The higher used doses (2 and 3 kGy) decreased acidity value, peroxide value and iodine value, and increased specification number, with no effect on TBA value. Irradiation had a significant effect on colour values of pistachio oil. Parameters L, a and b increased at doses of 1 and 2 kGy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Individual and co-operative roles of lactic acid and hydrogen peroxide in the killing activity of enteric strain Lactobacillus johnsonii NCC933 and vaginal strain Lactobacillus gasseri KS120.1 against enteric, uropathogenic and vaginosis-associated pathogens.

Science.gov (United States)

Atassi, Fabrice; Servin, Alain L

2010-03-01

The mechanism underlying the killing activity of Lactobacillus strains against bacterial pathogens appears to be multifactorial. Here, we investigate the respective contributions of hydrogen peroxide and lactic acid in killing bacterial pathogens associated with the human vagina, urinary tract or intestine by two hydrogen peroxide-producing strains. In co-culture, the human intestinal strain Lactobacillus johnsonii NCC933 and human vaginal strain Lactobacillus gasseri KS120.1 strains killed enteric Salmonella enterica serovar Typhimurium SL1344, vaginal Gardnerella vaginalis DSM 4944 and urinary tract Escherichia coli CFT073 pathogens. The cell-free culture supernatants (CFCSs) produced the same reduction in SL1344, DSM 4944 and CFT073 viability, whereas isolated bacteria had no effect. The killing activity of CFCSs was heat-stable. In the presence of Dulbecco's modified Eagle's minimum essential medium inhibiting the lactic acid-dependent killing activity, CFCSs were less effective at killing of the pathogens. Catalase-treated CFCSs displayed a strong decreased activity. Tested alone, hydrogen peroxide triggered a concentration-dependent killing activity against all three pathogens. Lactic acid alone developed a killing activity only at concentrations higher than that present in CFCSs. In the presence of lactic acid at a concentration present in Lactobacillus CFCSs, hydrogen peroxide displayed enhanced killing activity. Collectively, these results demonstrate that for hydrogen peroxide-producing Lactobacillus strains, the main metabolites of Lactobacillus, lactic acid and hydrogen peroxide, act co-operatively to kill enteric, vaginosis-associated and uropathogenic pathogens.

Effect of hyperbaric oxygen on lipid peroxidation and visual development in neonatal rats with hypoxia-ischemia brain damage.

Science.gov (United States)

Chen, Jing; Chen, Yan-Hui; Lv, Hong-Yan; Chen, Li-Ting

2016-07-01

The aim of the present study was to investigate the effect of hyperbaric oxygen (HBO) on lipid peroxidation and visual development in a neonatal rat model of hypoxic-ischemic brain damage (HIBD). The rat models of HIBD were established by delayed uterus dissection and were divided randomly into two groups (10 rats each): HIBD and HBO-treated HIBD (HIBD+HBO) group. Another 20 rats that underwent sham-surgery were also divided randomly into the HBO-treated and control groups. The rats that underwent HBO treatment received HBO (0.02 MPa, 1 h/day) 24 h after the surgery and this continued for 14 days. When rats were 4 weeks old, their flash visual evoked potentials (F-VEPs) were monitored and the ultrastructures of the hippocampus were observed under transmission electron microscope. The levels of superoxide dismutase (SOD) and malonyldialdehyde (MDA) in the brain tissue homogenate were detected by xanthine oxidase and the thiobarbituric acid colorimetric method. Compared with the control group, the ultrastructures of the pyramidal neurons in the hippocampal CA3 area were distorted, the latencies of F-VEPs were prolonged (P0.05). HBO enhances antioxidant capacity and reduces the ultrastructural damage induced by hypoxic-ischemia, which may improve synaptic reconstruction and alleviate immature brain damage to promote the habilitation of brain function.

Resveratrol suppresses ethanol stress in winery and bottom brewery yeast by affecting superoxide dismutase, lipid peroxidation and fatty acid profile.

Science.gov (United States)

Gharwalova, Lucia; Sigler, Karel; Dolezalova, Jana; Masak, Jan; Rezanka, Tomas; Kolouchova, Irena

2017-11-03

Mid-exponential cultures of two traditional biotechnological yeast species, winery Saccharomyces cerevisiae and the less ethanol tolerant bottom-fermenting brewery Saccharomyces pastorianus, were exposed to different concentrations of added ethanol (3, 5 and 8%) The degree of ethanol-induced cell stress was assessed by measuring the cellular activity of superoxide dismutase (SOD), level of lipid peroxidation products, changes in cell lipid content and fatty acid profile. The resveratrol as an antioxidant was found to decrease the ethanol-induced rise of SOD activity and suppress the ethanol-induced decrease in cell lipids. A lower resveratrol concentration (0.5 mg/l) even reduced the extent of lipid peroxidation in cells. Resveratrol also alleviated ethanol-induced changes in cell lipid composition in both species by strongly enhancing the proportion of saturated fatty acids and contributing thereby to membrane stabilization. Lower resveratrol concentrations could thus diminish the negative effects of ethanol stress on yeast cells and improve their physiological state. These effects may be utilized to enhance yeast vitality in high-ethanol-producing fermentations or to increase the number of yeast generations in brewery.

Aluminum induces lipid peroxidation and aggregation of human blood platelets

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T.J.C. Neiva

1997-05-01

Full Text Available Aluminum (Al3+ intoxication is thought to play a major role in the development of Alzheimer's disease and in certain pathologic manifestations arising from long-term hemodialysis. Although the metal does not present redox capacity, it can stimulate tissue lipid peroxidation in animal models. Furthermore, in vitro studies have revealed that the fluoroaluminate complex induces diacylglycerol formation, 43-kDa protein phosphorylation and aggregation. Based on these observations, we postulated that Al3+-induced blood platelet aggregation was mediated by lipid peroxidation. Using chemiluminescence (CL of luminol as an index of total lipid peroxidation capacity, we established a correlation between lipid peroxidation capacity and platelet aggregation. Al3+ (20-100 µM stimulated CL production by human blood platelets as well as their aggregation. Incubation of the platelets with the antioxidants nor-dihydroguaiaretic acid (NDGA (100 µM and n-propyl gallate (NPG (100 µM, inhibitors of the lipoxygenase pathway, completely prevented CL and platelet aggregation. Acetyl salicylic acid (ASA (100 µM, an inhibitor of the cyclooxygenase pathway, was a weaker inhibitor of both events. These findings suggest that Al3+ stimulates lipid peroxidation and the lipoxygenase pathway in human blood platelets thereby causing their aggregation

Evidence from in vivo 31-phosphorus magnetic resonance spectroscopy phosphodiesters that exhaled ethane is a biomarker of cerebral n-3 polyunsaturated fatty acid peroxidation in humans

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Hamilton Gavin

2008-04-01

Full Text Available Abstract Background This study tested the hypothesis that exhaled ethane is a biomarker of cerebral n-3 polyunsaturated fatty acid peroxidation in humans. Ethane is released specifically following peroxidation of n-3 polyunsaturated fatty acids. We reasoned that the cerebral source of ethane would be the docosahexaenoic acid component of membrane phospholipids. Breakdown of the latter also releases phosphorylated polar head groups, giving rise to glycerophosphorylcholine and glycerophosphorylethanolamine, which can be measured from the 31-phosphorus neurospectroscopy phosphodiester peak. Schizophrenia patients were chosen because of evidence of increased free radical-mediated damage and cerebral lipid peroxidation in this disorder. Methods Samples of alveolar air were obtained from eight patients and ethane was analyzed and quantified by gas chromatography and mass spectrometry (m/z = 30. Cerebral 31-phosphorus spectra were obtained from the same patients at a magnetic field strength of 1.5 T using an image-selected in vivo spectroscopy sequence (TR = 10 s; 64 signal averages localized on a 70 × 70 × 70 mm3 voxel. The quantification of the 31-phosphorus signals using prior knowledge was carried out in the temporal domain after truncating the first 1.92 ms of the signal to remove the broad component present in the 31-phosphorus spectra. Results The ethane and phosphodiester levels, expressed as a percentage of the total 31-phosphorus signal, were positively and significantly correlated (rs = 0.714, p Conclusion Our results support the hypothesis that the measurement of exhaled ethane levels indexes cerebral n-3 lipid peroxidation. From a practical viewpoint, if human cerebral n-3 polyunsaturated fatty acid catabolism can be measured by ethane in expired breath, this would be more convenient than determining the area of the 31-phosphorus neurospectroscopy phosphodiester peak.

Synthesis of Covalently Cross-Linked Colloidosomes from Peroxidized Pickering Emulsions

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Nadiya Popadyuk

2016-10-01

Full Text Available A new approach to the formation of cross-linked colloidosomes was developed on the basis of Pickering emulsions that were stabilized exclusively by peroxidized colloidal particles. Free radical polymerization and a soft template technique were used to convert droplets of a Pickering emulsion into colloidosomes. The peroxidized latex particles were synthesized in the emulsion polymerization process using amphiphilic polyperoxide copolymers poly(2-tert-butylperoxy-2-methyl-5-hexen-3-ine-co-maleic acid (PM-1-MAc or poly[N-(tert-butylperoxymethylacrylamide]-co-maleic acid (PM-2-MAc, which were applied as both initiators and surfactants (inisurfs. The polymerization in the presence of the inisurfs results in latexes with a controllable amount of peroxide and carboxyl groups at the particle surface. Peroxidized polystyrene latex particles with a covalently grafted layer of inisurf PM-1-MAc or PM-2-MAc were used as Pickering stabilizers to form Pickering emulsions. A mixture of styrene and/or butyl acrylate with divinylbenzene and hexadecane was applied as a template for the synthesis of colloidosomes. Peroxidized latex particles located at the interface are involved in the radical reactions of colloidosomes formation. As a result, covalently cross-linked colloidosomes were obtained. It was demonstrated that the structure of the synthesized (using peroxidized latex particles colloidosomes depends on the amount of functional groups and pH during the synthesis. Therefore, the size and morphology of colloidosomes can be controlled by latex particle surface properties.

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

Science.gov (United States)

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

2011-12-27

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

UVB-induced photoperoxidation of lipids of human low and high density lipoproteins. A possible role of tryptophan residues

International Nuclear Information System (INIS)

Salmon, S.; Maziere, J.C.; Santus, R.; Bouchemal, N.; Morliere, P.

1990-01-01

Ultraviolet radiation of the UVB region readily destroys tryptophan (Trp) residues of low (LDL) and high (HDL) density lipoproteins. The photooxidation of tryptophan residues is accompanied by peroxidation of low and high density lipoproteins unsaturated fatty acids, as measured by thiobarbituric acid assay. Moreover, low and high density lipoproteins are natural carriers of vitamin E and carotenoids. These two antioxidants are also rapidly bleached by UVB. The UVA radiation promotes neither tryptophan residue destruction nor lipid photoperoxidation. The redox cycling Cu 2+ ions considerably increase lipid photoperoxidation. The synergistic action of photo and auto (Cu 2+ -induced) peroxidation induces marked post-irradiation modifications of apolipoproteins as illustrated by degradation of most tryptophan residues after overnight incubation in the dark of pre-irradiated samples. (author)

Oxidative stability of Liposomes composed of docosahexaenoic acid-containing phospholipids

DEFF Research Database (Denmark)

Vikbjerg, Anders Falk; Andresen, Thomas Lars; Jørgensen, Kent

2007-01-01

Oxidative stability of liposomes made of (Docosahexaenoic acid) DHA-containing phosphatidylcholine (PC) was examined during preparation and storage. After preparation of the liposomes, the concentration of primary (conjugated dienes) and secondary oxidation products (Thiobarbituric acid...

A chemiluminescent method for determination of lipid peroxidation

International Nuclear Information System (INIS)

Liang Xiaofeng; Hu Tianxi; Fan Xiaobing

2003-01-01

We established a chemiluminescent system for determination of lipid peroxidation and screening anti-oxidants. The lipid containing unsaturated fatly acids was injected into a galls tube. Luminol solution and the deionized water were added into it too. The glass tube was put into a preincubation box to incubate it for 0.5 h at 37 degree C. AAPH solution was injected into the tube for immediate measurement in a biochemiluminometer at 38-39 degree C. The pulses /6s(CP6s) were determined with T-2 program. Chemiluminescent dynamic and lipid peroxidation changes were observed continuously. Once the CL intensity of lipid peroxidation got peak, the antioxidant which has different concentration was added immediately in situ. A certain CL intensity (CP6s) was chosen as evaluation index to compare the activity of antioxidants. A luminol chemiluminescent system for determination of lipid peroxidation has been made. It was found that Vit. C, teapolyphenol, and glutathione have effects on scavenging lipid free radicals. The new method is quick, sensitive, and simple for determination of lipid peroxidation and screening antioxidants

Mercury Induced Biochemical Alterations As Oxidative Stress In Mugil Cephalus In Short Term Toxicity Test

OpenAIRE

J.S.I Rajkumar; Samuel Tennyson

2013-01-01

Mugil cephalus juveniles of size 2.5 ±0.6cm were exposed to mercury in short term chronic toxicity test through static renewal bioassay to detect the possible biochemical agent as biomarkers in aquatic pollution and in estuarine contamination as specific. Lipid peroxidation levels, glutathione S -transferase, catalase, reduced glutathione and acetylcholinesterase were studied as biochemical parameters. Increased thio-barbituric acid reactive substances levels were observed under exposur...

The role of oxidative stress in streptozotocin-induced diabetic nephropathy in rats.

Science.gov (United States)

Fernandes, Sheila Marques; Cordeiro, Priscilla Mendes; Watanabe, Mirian; Fonseca, Cassiane Dezoti da; Vattimo, Maria de Fatima Fernandes

2016-10-01

The objective of this study was to evaluate the role of oxidative stress in an experimental model of streptozotocin-induced diabetic nephropathy in rats. Wistar, adult, male rats were used in the study. Animals were divided in the following groups: Citrate (control, citrate buffer 0.01M, pH 4.2 was administrated intravenously - i.v - in the caudal vein), Uninephrectomy+Citrate (left uninephrectomy-20 days before the study), DM (streptozotocin, 65 mg/kg, i.v, on the 20th day of the study), Uninephrectomy+DM. Physiological parameters (water and food intake, body weight, blood glucose, kidney weight, and relative kidney weight); renal function (creatinine clearance), urine albumin (immunodiffusion method); oxidative metabolites (urinary peroxides, thiobarbituric acid reactive substances, and thiols in renal tissue), and kidney histology were evaluated. Polyphagia, polydipsia, hyperglycemia, and reduced body weight were observed in diabetic rats. Renal function was reduced in diabetic groups (creatinine clearance, p < 0.05). Uninephrectomy potentiated urine albumin and increased kidney weight and relative kidney weight in diabetic animals (p < 0.05). Urinary peroxides and thiobarbituric acid reactive substances were increased, and the reduction in thiol levels demonstrated endogenous substrate consumption in diabetic groups (p < 0.05). The histological analysis revealed moderate lesions of diabetic nephropathy. This study confirms lipid peroxidation and intense consumption of the antioxidant defense system in diabetic rats. The association of hyperglycemia and uninephrectomy resulted in additional renal injury, demonstrating that the model is adequate for the study of diabetic nephropathy.

Social isolation stress-induced oxidative damage in mouse brain and its modulation by majonoside-R2, a Vietnamese ginseng saponin.

Science.gov (United States)

Huong, Nguyen Thi Thu; Murakami, Yukihisa; Tohda, Michihisa; Watanabe, Hiroshi; Matsumoto, Kinzo

2005-08-01

Stressors with a physical factor such as immobilization, electric foot shock, cold swim, etc., have been shown to produce oxidative damage to membrane lipids in the brain. In this study, we investigated the effect of protracted social isolation stress on lipid peroxidation activity in the mouse brain and elucidated the protective effect of majonoside-R2, a major saponin component of Vietnamese ginseng, in mice exposed to social isolation stress. Thiobarbituric acid reactive substance levels, one of the end products of lipid peroxidation reaction, were increased in the brains of mice subjected to 6-8 weeks of social isolation stress. Measurements of nitric oxide (NO) metabolites (NO(x)(-)) also revealed a significant increase of NO production in the brains of socially isolated mice. Moreover, the depletion of brain glutathione content, an endogenous antioxidant, in socially isolated animals occurred in association with the rise in lipid peroxidation. The intraperitoneal administration of majonoside-R2 (10-50 mg/kg) had no effect on thiobarbituric acid reactive substances (TBARS), NO, or glutathione levels in the brains of group-housed control mice but it significantly suppressed the increase in TBARS and NO levels and the decrease in glutathione levels caused by social isolation stress. These results suggest that mice subjected to 6-8 weeks of social isolation stress produces oxidative damage in the brain partly via enhancement of NO production, and that majonoside-R2 exerts a protective effect by modulating NO and glutathione systems in the brain.

Protective Effects of Ferulic Acid on High Glucose-Induced Protein Glycation, Lipid Peroxidation, and Membrane Ion Pump Activity in Human Erythrocytes.

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Weerachat Sompong

Full Text Available Ferulic acid (FA is the ubiquitous phytochemical phenolic derivative of cinnamic acid. Experimental studies in diabetic models demonstrate that FA possesses multiple mechanisms of action associated with anti-hyperglycemic activity. The mechanism by which FA prevents diabetes-associated vascular damages remains unknown. The aim of study was to investigate the protective effects of FA on protein glycation, lipid peroxidation, membrane ion pump activity, and phosphatidylserine exposure in high glucose-exposed human erythrocytes. Our results demonstrated that FA (10-100 μM significantly reduced the levels of glycated hemoglobin (HbA1c whereas 0.1-100 μM concentrations inhibited lipid peroxidation in erythrocytes exposed to 45 mM glucose. This was associated with increased glucose consumption. High glucose treatment also caused a significant reduction in Na+/K+-ATPase activity in the erythrocyte plasma membrane which could be reversed by FA. Furthermore, we found that FA (0.1-100 μM prevented high glucose-induced phosphatidylserine exposure. These findings provide insights into a novel mechanism of FA for the prevention of vascular dysfunction associated with diabetes.

Transformation using peroxide of a crude thorium hydroxide in nitrate for mantle grade

International Nuclear Information System (INIS)

Freitas, Antonio Alves de; Carvalho, Fatima Maria Sequeira de; Ferreira, Joao Coutinho; Abrao, Alcidio

2002-01-01

An alternative process for the recovery and purification of thorium starting from a crude thorium hydroxide as the precursor is outlined in this paper. Its composition is 60.1% thorium oxide (ThO 2 ), 18.6% rare earth oxides (TR 2 O 3 ), and common impurities like silicium, iron, titanium, lead and sodium. This material was produced industrially from the monazite processing in Brazil and has been stocked since several years. The crude thorium hydroxide is treated with hot nitric acid and after the digestion and addition of floculant it is filtered for the separation of the insoluble fraction. Using this nitrate solution, the thorium peroxide is precipitated after adjustment of pH and controlled addition of hydrogen peroxide. The final thorium peroxide is dissolved with nitric acid and the resulting thorium nitrate is mantle grade quality. Rare earth elements are recovered from the thorium peroxide filtrate. The main process parameters for the peroxide precipitation, like pH and temperature and main the results are presented and discussed. (author)

Lipid peroxidation in radiation pneumonitis in mouse lung and its preventation

International Nuclear Information System (INIS)

Kodama, Akihisa; Tsujino, Kayoko; Kono, Michio

1998-01-01

Lipid peroxidation of the lung in irradiated C57BL6J mice was analyzed by gas chromatography. Among six major fatty acids in the mouse lung tissue, the amounts of two unsaturated fatty acids, arachidonic acid and DHA reduced one day after irradiation, and then recovered up to the level of in the control group four weeks after irradiation. In contrast, the amounts of stearic and palmitic acid did not change significantly. The mice fed with vitamin E-enriched food showed no significant changes of fatty acids which were compatible with pathophysiological findings 4 weeks after irradiation. Reduction of both arachidonic acid and DHA following lipid peroxidation in lung tissue, was assumed to play an important role in development of radiation pneumonitis. Vitamin E seems to enable to prevent or reduce the occurrence and progression of radiation pneumonitis, but as a radical scavenger, it may also weaken the anti-tumor growth effect of low linear energy transfer (LET) irradiation as photon. (author)

An EPR study on wastewater disinfection by peracetic acid, hydrogen peroxide and UV irradiation.

Science.gov (United States)

Bianchini, Roberto; Calucci, Lucia; Caretti, Cecilia; Lubello, Claudio; Pinzino, Calogero; Piscicelli, Michela

2002-09-01

EPR spectroscopy was applied to obtain qualitative and quantitative information on the radicals produced in disinfection processes of wastewater for agricultural reuse. The DEPMPO spin trap was employed to detect hydroxyl and carbon-centered short living radicals in two different peracetic acid solutions and a hydrogen peroxide solution used for water disinfection either in the absence or in the presence of UV-C irradiation. Moreover, three different kinds of water (wastewater, demineralized water, distilled water) were analysed in order to assess the contribution of Fenton reactions to the radical production. The spectroscopic results were discussed in relation to the efficiency of the different oxidizing agents and UV irradiation in wastewater disinfection evaluated as Escherichia Coli, Faecal and Total Coliforms inactivation.

Uranium peroxide precipitate drying temperature relationships

Energy Technology Data Exchange (ETDEWEB)

Rodgers, C.; Dyck, B., E-mail: chick_rodgers@cameco.com [Cameco Corp., Saskatoon, SK (Canada)

2010-07-01

Cameco Corporation is in the process of revitalizing the mill at its Key Lake operation in northern Saskatchewan. The current Key Lake process employs ammonia stripping and ammonia precipitation. As part of the revitalization, the company is considering installing strong acid stripping in solvent extraction as used at its Rabbit Lake operation. This change would lead to using hydrogen peroxide for uranium precipitation. As part of the process evaluation, tests were carried out to study how changes in the temperature of an indirect fired dryer affected the properties of uranium peroxide [yellowcake] precipitate. This paper discusses the results of the test work, including the relationships between drying temperature and the following: (author)

The Potential Use of Secondary Metabolites in Moringa oleifera as an Antioxidant Source

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A. Fitri

2015-12-01

Full Text Available This present study determined antioxidant activity, lipid peroxidation, total phenolic, total flavonoids and phytochemicals in moringa leaves and moringa stem. Analysis used in this study was 1, 1-diphenyl-2-picrylhydrazyl (DPPH method for antioxidant activity, thiobarbituric acid reactive substances (TBARS method for lipid peroxidation, Folin-Ciocalteu method for total phenolic, total flavonoid and UFLC (Ultrafast Liquid Chromatography for identification and quantification of phenolic compounds. The results showed that moringa leaves had higher ability to scavenge free radical, total phenolic, and total flavonoid than moringa stem (P<0.001. Malondialdehyde production, the end product of lipid peroxidation, in moringa leaves was lower than moringa stem (P<0.001. Ferulic acid was the major active compound in both moringa leaves and moringa stem. This present study indicated that moringa leaves and moringa stem could be used as feed additive which had a good potential to prevent oxidative stress in animals.

Effect of salting on back fat hydrolysis and oxidation

Science.gov (United States)

Tunieva, E. К; Nasonova, V. V.; Stanovova, I. A.; Spiridonov, К I.; Kurzova, A. A.

2017-09-01

Technological factors significantly affect the rate of hydrolytic and oxidative changes in fat. The aim of the research was to study the effect of sodium chloride on hydrolysis and oxidation of fat raw material, including the impact of thermal treatment. Back fat was minced, sodium chloride was added (in amounts of 0.0, 2.0, 3.5 or 5.0%), then it was thermally treated or not. Determination of the acid value (AV) was carried out by titration with aqueous potassium hydroxide of free fatty acids in the ether-alcohol solution of back fat; the peroxide value (PV) was based on oxidation of iodhydric acid with peroxides contained in fat followed by titration of released iodine with sodium thiosulphate. The thiobarbituric acid value (TBAV) was determined by the development of stained substances due to interaction of fat oxidation products with 2-thiobarbituric acid and measurement of color intensity using a spectrophotometer. Adding 5.0% sodium chloride to back fat led to a 30.1% decrease in AV. Addition of 2.0% sodium chloride inhibited the development of the oxidation products and led to a 17% decrease in the PV and to a 25% decrease in TBAV (p0.05). The results obtained showed an ambiguous effect of sodium chloride on the processes of fat oxidation, depending on dosage and the use of thermal treatment, justifying the necessity to develop approaches that allow reduction of the sodium chloride content in meat products that are not subjected to thermal treatment.

Amelioration of ionizing radiation induced lipid peroxidation in mouse liver by Moringa oleifera Lam. leaf extract

International Nuclear Information System (INIS)

Sinha, Mahuya; Das, Dipesh Kr; Dey, Sanjit; Datta, Sanjukta; Ghosh, Santinath

2012-01-01

Protective effect of Moringa oleifera leaf extract (MoLE) against radiation-induced lipid peroxidation has been investigated. Swiss albino mice, selected from an inbred colony, were administered with MoLE (300 mg/kg body wt) for 15 days before exposing to a single dose of 5 Gy 60 Co-gamma radiation. After treatments, animals were necropsied at different post irradiation intervals (days 1, 7 and 15) and hepatic lipid peroxidation and reduced glutathione (GSH) contents were estimated to observe the relative changes due to irradiation and its possible amelioration by MoLE. It was observed that, MoLE treatment restored GSH in liver and prevented radiation induced augmentation in hepatic lipid peroxidation. Phytochemical analysis showed that MoLE possess various phytochemicals such as ascorbic acid, phenolics (catechin, epicatechin, ferulic acid, ellagic acid, myricetin) etc., which may play the key role in prevention of hepatic lipid peroxidation by scavenging radiation induced free radicals. (author)

Immunoaffinity Knockout of Saponin Glycosides from Asparagus racemosus to Assess Anti-lipid Peroxidation.

Science.gov (United States)

Onlom, Churanya; Phrompittayarat, Watoo; Putalun, Waraporn; Waranuch, Neti; Ingkaninan, Kornkanok

2017-07-01

Asparagus racemosus Willd (Asparagaceae family), known as Shatavari, is important in Ayurveda and traditional Thai medicines. The saponin glycosides, shatavarin I and IV are major constituents in its roots and may be responsible for their actions including protection against lipid peroxidation and carcinogenesis. To develop an immunoaffinity column for isolating compounds with structures related to shatavarin IV from crude extracts of A. racemosus root. The monoclonal antibody recognising shatavarin IV (mAbShavIV) was coupled to an Affi-Gel Hz gel to isolate compounds with structures related to shatavarin IV from the other components of crude extracts of A. racemosus root. The saponin glycosides in each fraction were analysed by mAbShavIV ELISA and LC-MS/MS. The pooled wash-through fractions contained 3% of loaded mAbShavIV reactive saponin glycosides, while eluted fractions released ~ 90% of shatavarin saponin glycosides in a single step. Using thiobarbiturate (TBARs) to measure lipid-peroxidation, the extract, and the pooled wash-through fractions showed moderate protection against Cu + -induced oxidation of human low density lipoprotein (LDL) (IC 50 11.3 ± 1.4 and 12.6 ± 0.9 μg/mL, respectively). In contrast, the saponin glycosides eluted from the mAbShavIV-column had weaker protectant (IC 50 29.7 ± 1.8 μg/mL) suggesting that A. racemosus shatavarins do not inhibit carcinogenesis through preventing lipid peroxidation. The strategy described here demonstrates its utility for isolating a group of related compounds from the rest of the extract with selectivity and recovery rate. Pharmacological efficacy and synergistic effects of the components obtained can be further investigated. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Evaluation of human dental loss caused by carbamide peroxide bleacher compared with phosphoric acid conditioning - radioactive method; Avaliacao da perda dental humana com o uso do clareador peroxido de carbamida comparado ao condicionamento com acido fosforico - metodo radiometrico

Energy Technology Data Exchange (ETDEWEB)

Adachi, Eduardo Makoto; Yousseff, Michel Nicolau [Sao Paulo Univ., SP (Brazil). Faculdade de Odontologia. Dept. de Dentistica; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Lab. de Analise por Ativacao Neutronica

2002-07-01

The radiometric method was applied to the evaluation of dental loss caused by carbamide peroxide when it is applied on the surface layers of enamel and dentin tissues. Also the dental loss caused by the etching with 37% phosphoric acid procedure used in aesthetic restoration was assessed for comparison with those results obtained. The tooth samples irradiated with a P standard in a thermal neutron flux of the nuclear reactor were placed in contact with 10% carbamide peroxide or with 37% phosphoric acid solution. The radioactivity of {sup 32} P transferred from the radioactive teeth to the bleaching gel or to etching acid was measured using a Geiger Muller detector to calculate the mass of P removed in this treatment and losses were calculated after obtaining their P concentrations. Results obtained indicated that enamel and dentin exposed to carbamide peroxide bleaching agent lose phosphorus. The extent of enamel loss was smaller than that obtained for dentin. In the case of acid etching, there was no difference between the results obtained for enamel and dentin loss. Also the dentin loss obtained after a treatment of 30 applications of 10% carbamide peroxide was the same magnitude of that one application of 37% phosphoric acid. (author)

Comparision of Inhibitory effects of Satureja Khozistanica,vitamin E and coenzyme Q10 on LDL peroxidation induced-CuSO4 in vitro

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hasan Ahmadvand

2010-02-01

Full Text Available Oxidation of low-density lipoprotein (LDL has been strongly suggested as a key factor in the pathogenesis of atherosclerosis. Thus the inclusion of some anti-oxidant compounds such as Satureja Khozistanica,vitamin E and coenzyme Q10 in daily dietary food stuff may inhibit the production of oxidized LDL and may decrease both the development and the progression of atherosclerosis. The present study investigated the inhibitory effects of Satureja Khozistanica, vitamin E and coenzyme Q10 on LDL peroxidation induced by CuSO4 quantitatively in vitro. Materials and Methods: LDL was incubated with CuSO4 and the formation of conjugated dienes and thiobarbituric acid reactive substances (TBARS of LDL were monitored as markers of LDL oxidation. Inhibition of this Cu-induced oxidation was studied in the presence of extracts of Satureja Khozistanica,vitamin E and coenzyme Q10. Results: It was demonstrated that Satureja Khozistanica like vitamin E and coenzyme Q10 is able to inhibit LDL oxidation and decrease the resistance of LDL against oxidation in vitro. Conclusion: This study showed that Satureja Khozistanica similar to vitamin E and coenzyme Q10 prevented the oxidation of LDL in vitro and it may suggest that they have the similar effect in vivo

Effects of curcumin and ursolic acid on the mitochondrial coupling efficiency and hydrogen peroxide emission of intact skeletal myoblasts.

Science.gov (United States)

Tueller, Daniel J; Harley, Jackson S; Hancock, Chad R

2017-10-21

Curcumin may improve blood glucose management, but the mechanism is not fully established. We demonstrated that curcumin (40 μM) reduced the mitochondrial coupling efficiency (percentage of oxygen consumption coupled to ATP synthesis) of intact skeletal muscle cells. A 30-minute pretreatment with curcumin reduced mitochondrial coupling efficiency by 17.0 ± 0.4% relative to vehicle (p Curcumin pretreatment also decreased the rate of hydrogen peroxide emission by 43 ± 13% compared to vehicle (p curcumin revealed a 40 ± 4% increase in the rate of oxygen consumption upon curcumin administration (p curcumin-pretreated cells after permeabilization of cell membranes (p > 0.7). The interaction between curcumin and ursolic acid, another natural compound that may improve blood glucose management, was also examined. Pretreatment with ursolic acid (0.12 μM) increased the mitochondrial coupling efficiency of intact cells by 4.1 ± 1.1% relative to vehicle (p curcumin when the two compounds were used in combination. The observed changes to mitochondrial coupling efficiency and hydrogen peroxide emission were consistent with the established effects of curcumin on blood glucose control. Our findings also show that changes to mitochondrial coupling efficiency after curcumin pretreatment may go undetected unless cells are assessed in the intact condition. Copyright © 2017 Elsevier Inc. All rights reserved.

A diet rich in conjugated linoleic acid and butter increases lipid peroxidation but does not affect atherosclerotic, inflammatory, or diabetic risk markers in healthy young men

DEFF Research Database (Denmark)

Raff, Marianne; Tholstrup, Tine; Basu, Samar

2008-01-01

Intake of conjugated linoleic acid (CLA) has been demonstrated to beneficially affect risk markers of atherosclerosis and diabetes in rats. CLA is naturally found in milk fat, especially from cows fed a diet high in oleic acid, and increased CLA intake can occur concomitantly with increased milk...... fat intake. Our objective was to investigate the effect of CLA as part of a diet rich in butter as a source of milk fat on risk markers of atherosclerosis, inflammation, diabetes type 11, and lipid peroxidation. A total of 38 healthy young men were given a diet with 115g/d of CLA-rich fat (5.5 g/d CLA...... esters, and phospholipids reflected that of the intervention diets. The CLA diet resulted in increased lipid peroxidation measured as an 83% higher 8-iso-prostaglandin F-2 alpha concentration compared with the control, P...

Effect of dietary docosahexaenoic acid connecting phospholipids on the lipid peroxidation of the brain in mice.

Science.gov (United States)

Hiratsuka, Seiichi; Ishihara, Kenji; Kitagawa, Tomoko; Wada, Shun; Yokogoshi, Hidehiko

2008-12-01

The effect of dietary docosahexaenoic acid (DHA, C22:6n-3) with two lipid types on lipid peroxidation of the brain was investigated in streptozotocin (STZ)-induced diabetic mice. Each group of female Balb/c mice was fed a diet containing DHA-connecting phospholipids (DHA-PL) or DHA-connecting triacylglycerols (DHA-TG) for 5 wk. Safflower oil was fed as the control. The lipid peroxide level of the brain was significantly lower in the mice fed the DHA-PL diet when compared to those fed the DHA-TG and safflower oil diets, while the alpha-tocopherol level was significantly higher in the mice fed the DHA-PL diet than in those fed the DHA-TG and safflower oil diets. The DHA level of phosphatidylethanolamine in the brain was significantly higher in the mice fed the DHA-PL diet than in those fed the safflower oil diet. The dimethylacetal levels were significantly higher in the mice fed the DHA-PL diet than in those fed the safflower oil and DHA-TG diets. These results suggest that the dietary DHA-connecting phospholipids have an antioxidant activity on the brain lipids in mice, and the effect may be related to the brain plasmalogen.

Interaction of Polyamines, Abscisic Acid, Nitric Oxide, and Hydrogen Peroxide under Chilling Stress in Tomato (Lycopersicon esculentum Mill.) Seedlings

OpenAIRE

Diao, Qiannan; Song, Yongjun; Shi, Dongmei; Qi, Hongyan

2017-01-01

Polyamines (PAs) play a vital role in the responses of higher plants to abiotic stresses. However, only a limited number of studies have examined the interplay between PAs and signal molecules. The aim of this study was to elucidate the cross-talk among PAs, abscisic acid (ABA), nitric oxide (NO), and hydrogen peroxide (H2O2) under chilling stress conditions using tomato seedlings [(Lycopersicon esculentum Mill.) cv. Moneymaker]. The study showed that during chilling stress (4°C; 0, 12, and 2...

Destruction of oxalate by reaction with hydrogen peroxide. [Hydrazine oxalate

Energy Technology Data Exchange (ETDEWEB)

Mailen, J.C.; Tallent, O.K.; Arwood, P.C.

1981-09-01

The destruction of oxalate by oxidation to carbon dioxide using hydrogen peroxide was studied as an alternative method for the disposal of oxalate in connection with the possible use of an aqueous hydrazine oxalate solution as a scrubbing agent for solvent cleanup in processes for the recovery of uranium, plutonium, and thorium by solvent extraction. The rate of oxidation of oxalate by hydrogen peroxide in acid solution at the reflux temperature was adequate for process application; reaction half-times at 100/sup 0/C were less than one hour when the hydrogen peroxide concentration was greater than 0.5 M. The reaction was first order with respect to both the oxalate and hydrogen peroxide concentrations and had an activation energy of 58.7 kJ/g-mol. The rate increased with the hydrogen ion concentration as (H/sup +/)/sup 0/ /sup 3/ but was not significantly affected by the presence of 100 ppM of uranium or copper in solution. In the near-neutral hydrazine oxalate solutions, the reaction of either component with hydrogen peroxide was too slow for process application.

Effect of antioxidant inclusion and oil quality on broiler performance, meat quality, and lipid oxidation.

Science.gov (United States)

Tavárez, M A; Boler, D D; Bess, K N; Zhao, J; Yan, F; Dilger, A C; McKeith, F K; Killefer, J

2011-04-01

The objective of the present study was to evaluate the effect of antioxidant inclusion and oil quality on broiler performance, meat quality, shelf life, and tissue oxidative status. Ross 308 male broilers were allotted to a randomized complete block design in a 2 × 2 factorial arrangement. Factors consisted of antioxidant (ethoxyquin and propyl gallate) inclusion at 2 levels (0 or 135 mg/kg) and oil quality (fresh soybean oil, control diet peroxide value dressing percentage (P = 0.906), breast yield (P = 0.708), or breast ultimate pH (P = 0.625) and had minimal effect on breast color. Antioxidant supplementation (P = 0.057) reduced breast thiobarbituric acid reactive substances after 7 d of display. Fresh oil decreased liver thiobarbituric acid reactive substances, whereas antioxidant inclusion increased serum and liver vitamin A and E concentration. The presence of an antioxidant in the feed protects lipids from further oxidizing, therefore increasing broiler performance and improving shelf life when using oxidized oil.

Preparation of water soluble chitosan by hydrolysis using hydrogen peroxide.

Science.gov (United States)

Xia, Zhenqiang; Wu, Shengjun; Chen, Jinhua

2013-08-01

Chitosan is not soluble in water, which limits its wide application particularly in the medicine and food industry. In the present study, water soluble chitosan (WSC) was prepared by hydrolyzing chitosan using hydrogen peroxide under the catalysis of phosphotungstic acid in homogeneous phase. Factors affecting hydrolysis were investigated and the optimal hydrolysis conditions were determined. The WSC structure was characterized by Fourier transform infrared spectroscopy. The resulting products were composed of chitooligosaccharides of DP 2-9. The WSC content of the product and the yield were 94.7% and 92.3% (w/w), respectively. The results indicate that WSC can be effectively prepared by hydrolysis of chitosan using hydrogen peroxide under the catalysis of phosphotungstic acid. Copyright © 2013 Elsevier B.V. All rights reserved.

Potensi Antioksidan sebagai Antidiabetes

OpenAIRE

Widowati, Wahyu

2008-01-01

Diabetes mellitus (DM) is a syndrome  that is marked by elevated blood sugar level. DM is  categorized into two types:  type 1 DM is called insulin-dependent diabetes mellitus (IDDM) and type 2 DM is  called non-insulin-dependent diabetes mellitus (NIDDM). Glucose can be oxidized before or after bound with protein (glycated protein), producing Reactive Oxygen Species (ROS). Diabetic patients indicate lipid peroxide and Thiobarbituric Acid Reactive Subtances  (TBARS) p...

Solvent-dependent regioselective oxidation of trans-chalcones using aqueous hydrogen peroxide

Energy Technology Data Exchange (ETDEWEB)

Peng, Wang; Jiabin, Yang; Lushen, Li, E-mail: jimin@seu.edu.cn [Southeast University, Nanjing (China). School of Biological Science and Medical Engineering; Jin, Cai; Chunlong, Sun; Min, Ji [Southeast University, Nanjing (China). School of Chemistry and Chemical Engineering

2013-03-15

A novel method for regioselective oxidation of trans-chalcones with hydrogen peroxide in acetonitrile to afford cinnamic acids is reported. Only trans-b-arylacrylic acids were observed. A wide range of functionalized products can be effectively produced from various chalcones in good to excellent yields. (author)

The influence of hydroxyurea on oxidative stress in sickle cell anemia

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Lidiane de Souza Torres

2012-01-01

Full Text Available OBJECTIVE: The oxidative stress in 20 sickle cell anemia patients taking hydroxyurea and 13 sickle cell anemia patients who did not take hydroxyurea was compared with a control group of 96 individuals without any hemoglobinopathy. METHODS: Oxidative stress was assessed by thiobarbituric acid reactive species production, the Trolox-equivalent antioxidant capacity and plasma glutathione levels. RESULTS: Thiobarbituric acid reactive species values were higher in patients without specific medication, followed by patients taking hydroxyurea and the Control Group (p < 0.0001. The antioxidant capacity was higher in patients taking hydroxyurea and lower in the Control Group (p = 0.0002 for Trolox-equivalent antioxidant capacity and p < 0.0292 for plasma glutathione. Thiobarbituric acid reactive species levels were correlated with higher hemoglobin S levels (r = 0.55; p = 0.0040 and lower hemoglobin F concentrations(r = -0.52; p = 0.0067. On the other hand, plasma glutathione levels were negatively correlated with hemoglobin S levels (r = -0.49; p = 0.0111 and positively associated with hemoglobin F values (r = 0.56; p = 0.0031. CONCLUSION: Sickle cell anemia patients have high oxidative stress and, conversely, increased antioxidant activity. The increase in hemoglobin F levels provided by hydroxyurea and its antioxidant action may explain the reduction in lipid peroxidation and increased antioxidant defenses in these individuals.

Transition metal-free oxidation of benzylic alcohols to carbonyl compounds by hydrogen peroxide in the presence of acidic silica gel

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Hossein Ghafuri

2015-01-01

Full Text Available Oxidation of alcohols to carbonyl compounds has become an important issue in the process industry as well as many other applications. In this method, various benzylic alcohols were successfully converted to corresponding aldehydes and ketones under transition metal-free condition using hydrogen peroxide in the presence of some amount of catalytic acidic silica gel. Silica gel is inexpensive and available. One of the most important features of this method is its short reaction time.

Facile syntheses of bioactive 5-arylidenethiobarbituric acids

International Nuclear Information System (INIS)

Sharif, A.; Ahmed, E.; Munawar, M.A.; Jabeen, S.; Khan, Misbah-ul-Ain; Begum, R.; Farrukh, A.; Ashraf, M.; Arshad, S.; Afza, N.

2011-01-01

A simple and green chemistry route for the preparation of 5- arylidenethiobarbituric acids has been developed by Knoevenagel condensation of thiobarbituric acid with different aromatic and heteroaromatic aldehydes using catalytic amount of acetic acid by grinding in mortar and pestle. The title compounds were obtained in good to high yields (50-89%) and characterized by IR, NMR, mass spectroscopy and elemental analysis. All compounds exhibited DPPH radical scavenging and antibacterial activities, respectively. (author)

Algal toxicity of the alternative disinfectants performic acid (PFA), peracetic acid (PAA), chlorine dioxide (ClO2) and their by-products hydrogen peroxide (H2O2) and chlorite (ClO2-).

Science.gov (United States)

Chhetri, Ravi Kumar; Baun, Anders; Andersen, Henrik Rasmus

2017-05-01

Environmental effect evaluation of disinfection of combined sewer overflow events with alternative chemical disinfectants requires that the environmental toxicity of the disinfectants and the main by-products of their use are known. Many disinfectants degrade quickly in water which should be included in the evaluation of both their toxicity as determined in standardized tests and their possible negative effect in the water environment. Here we evaluated according to the standardized ISO 8692 test the toxicity towards the green microalgae, Pseudokirchneriella subcapitata, of three disinfectants: performic acid (PFA), peracetic acid (PAA) and chlorine dioxide (ClO 2 ) as well as two by-products of their use: hydrogen peroxide (H 2 O 2 ) and chlorite. All of the five chemicals investigated showed clear toxicity to the algae with well-defined dose response curves. The EC 50 values ranged from 0.16 to 2.9mg/L based on nominal concentrations leading to the labeling of the chemicals as either toxic or very toxic. The five investigated chemicals decreased in toxicity in the order chlorine dioxide, performic acid, peracetic acid, chlorite and hydrogen peroxide. The stability of the chemicals increased in the same order as the toxicity decrease. This indicates that even though ClO 2 has the highest environmental hazard potential, it may still be suitable as an alternative disinfectant due to its rapid degradation in water. Copyright © 2016 Elsevier GmbH. All rights reserved.

Optimization of the In Situ Epoxidation of Linoleic Acid of Jatropha Curcas Oil With Performic Acid

International Nuclear Information System (INIS)

Hong, L.K.; Rahimi Mohd Yusop; Nadia Salih; Jumat Salimon

2015-01-01

The aim of this study is to optimise the epoxidation of linoleic acid of Jatropha curcas oil. This experiment was carried out with performic acid generated in situ by using hydrogen peroxide and formic acid. The method was evaluated on different parameters such as reaction temperature, mole ratios of formic acid to ethylenic unsaturation and hydrogen peroxide to ethylenic unsaturation. The optimum relative conversion into oxirane (80.4 %) and conversion of iodine (94.7 %) was achieved with ∼70 % yield at the condition of 45 degree Celsius reaction temperature, formic acid to ethylenic unsaturation mole ratio of 2.0, hydrogen peroxide to ethylenic unsaturation mole ratio of 12.0 for 2 hours of reaction time. The epoxidized linoleic acid was characterized by using Fourier transform infrared (FTIR) spectroscopy and NMR analysis. The result was also found that the formations of an epoxide and oxirane ring cleavage were both occurred at the same time if low amount of hydrogen peroxide was used. (author)

The Effectiveness of Rambutan (Nephelium lappaceum L.) Extract in Stabilization of Sunflower Oil under Accelerated Conditions.

Science.gov (United States)

Mei, Winne Sia Chiaw; Ismail, Amin; Esa, Norhaizan Mohd; Akowuah, Gabriel Akyirem; Wai, Ho Chun; Seng, Yim Hip

2014-05-09

The oxidative properties of sunflower oil supplemented with rambutan extract, (crude extract and its fractionated fraction, SF II) in comparison with synthetic antioxidant were investigated. The supplemented sunflower oils were stored under accelerated conditions for 24 days at 60 °C. For every 6-day interval, the oxidative properties of the supplemented sunflower oil were evaluated based on the following tests, namely peroxide value, p-anisidine value, Thiobarbituric Acid Reactive Substances (TBARS) assay, iodine value and free fatty acids. The total oxidation (TOTOX) values were also calculated based on the peroxide values and p-anisidine values. Rambutan extract is a potential source of antioxidant. The oxidative activities of the extracts at all concentrations were significantly (p rambutan extract could be used as a potential alternative source of antioxidant in the oil industry or other fat-based products to delay lipid oxidation.

Effect of sibutramine on 5-hydroxyindole acetic acid levels and selected oxidative biomarkers on brain regions of female rats in the presence of zinc.

Science.gov (United States)

Guzmán, David C; García, Ernestina H; Mejía, Gerardo B; Olguín, Hugo J; Jiménez, Francisca T; Soto, Erick B; Del Angel, Daniel S; Aparicio, Liliana C

2012-05-01

A number of drugs, like sibutramine, which are used clinically in weight control, act on serotonergic metabolism. However, their relation with zinc and free radical (FR) production in central nervous system remains unknown. This study aimed to evaluate the effect of sibutramine and zinc on FR production. Female Wistar rats (about 250 g) were used in this study. The animals received 400 μg/kg of zinc and 10 mg/kg of sibutramine intraperitoneally every 36 hr for 15 days. At the end of the study, the rats were killed and their brains used for the measurement of lipid peroxidation thiobarbituric acid-reactive substances (TBARS), reduced glutathione (GSH), hydrogen peroxide (H(2) O(2) ), calcium and 5-hydroxyindole acetic acid (5-HIAA) levels, all by means of validated methods. Corporal weight and food consumption were found to be decreased in the zinc/sibutramine group. TBARS decreased in cortex, hemispheres and medulla oblongata. GSH decreased in cortex, hemispheres and cerebellum in the sibutramine group. Zinc given alone and in combination with sibutramine decreased H(2) O(2) concentration in cortex, hemispheres and cerebellum but increased calcium and 5-HIAA concentration in all brain regions. Our results suggest that sibutramine and zinc are associated with weight loss, an effect that was more pronounced in the group treated with both drugs. Reduction in oxidative stress may be involved in these effects. © 2011 The Authors. Basic & Clinical Pharmacology & Toxicology © 2011 Nordic Pharmacological Society.

Peroxide scavenging potential of ultraviolet-B-absorbing mycosporine-like amino acids isolated from a marine red alga Bryocladia sp.

Directory of Open Access Journals (Sweden)

Vinod K Kannaujiya

2014-06-01

Full Text Available Ultraviolet-B (UV-B; 280-315 nm-absorbing mycosporine-like amino acids (MAAs were extracted and purified from a marine red alga Bryocladia sp. by using high performance liquid chromatography. We have detected four MAAs having retention times 3.23, 2.94, 3.56 and 2.67 min with absorbance maxima (λmax at 323, 328, 335 and 340 nm respectively. The effect of UV-B on the induction of these MAAs was studied. In comparison to control, there was 3 - 22 % induction of MAAs after 12 and 24 h of UV-B exposure. Apart from MAAs, other pigments such as chl a, carotenoids and total proteins were inversely affected by UV-B irradiation. In addition, peroxide scavenging potential of these MAAs were also investigated. With 2 mM hydrogen peroxide (H2O2 concentration, only <5 % of MAAs were found to be affected. However, with the increased H2O2, 40-60 % decline in the MAAs concentration with a corresponding peak shifting towards the blue wavelength was recorded. In addition, most of the MAAs were found to be reacting slowly with increasing H2O2 (upto 10 mM concentration after an incubation period of 5 and 30 min, which indicates the remarkable scavenging potential and stability of MAAs against oxidative stress. Thus, the isolated MAAs from marine red alga Bryocladia sp. may act as an efficient peroxide scavenger.

Evaluation of Chemical Constituents and Antioxidant Activity of Coconut Water (Cocus nucifera L. and Caffeic Acid in Cell Culture

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JOAO L.A. SANTOS

2013-09-01

Full Text Available Coconut water contains several uncharacterized substances and is widely used in the human consumption. In this paper we detected and quantified ascorbic acid and caffeic acid and total phenolics in several varieties of coconut using HPLS/MS/MS (25.8 ± 0.6 µg/mL and 1.078 ± 0.013 µg/mL and 99.7 µg/mL, respectively, in the green dwarf coconut water, or 10 mg and 539 µg and 39.8 mg for units of coconut consumed, 500 ± 50 mL. The antioxidant potential of four coconut varieties (green dwarf, yellow dwarf, red dwarf and yellow Malaysian was compared with two industrialized coconut waters and the lyophilized water of the green dwarf variety. All varieties were effective in scavenging the DPPH radical (IC50=73 µL and oxide nitric (0.1 mL with an IP of 29.9% as well as in inhibiting the in vitro production of thiobarbituric acid reactive substances (1 mL with an IP of 34.4%, highlighting the antioxidant properties of the green dwarf which it is the most common used. In cell culture, the green dwarf water was efficient in protecting against oxidative damages induced by hydrogen peroxide.

Effects of Uric Acid on Exercise-induced Oxidative Stress

OpenAIRE

平井, 富弘

2001-01-01

We studied effects of uric acid on exercise― induced oxidative stress in humans based on a hypothesis that uric acid acts as an antioxidant to prevent from exercise―induced oxidative stress. Relation between uric acid level in plasma and increase of thiobarbituric acid reactive substance (TBARS)after the cycle ergometer exercise was examined. Thiobarbituricacid reactive substance in plasma increased after the ergometer exercise. High uric acid in plasma did not result in low increase of TBARS...

Catalytic wet peroxide oxidation of formic acid in wastewater with ...

African Journals Online (AJOL)

2016-07-03

Jul 3, 2016 ... The reaction was monitored by ATR FTIR by following the disappearance of the O-H ..... of hydrogen peroxide than other iron ions such as FeCl2, FeCl3, ..... HWANG D-S, LEE E-H, KIM K-W, LEE K-I and PARK S-J (1999).

The effect of vacuum packaging on physicochemical changes in rainbow trout (Oncorhynchus mykiss during cold storage

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František Ježek

2014-01-01

Full Text Available The aim of the study was to monitor changes in selected physical (awwater activity, pH values and chemical (TVBN total volatile basic nitrogen, TMA-N trimethylamine nitrogen, FFA free fatty acids, PV peroxide values, TBA thiobarbituric acid value properties in the shelf life of rainbow trout (Oncorhynchus mykiss muscle. A total of 192 trout were examined. Control samples (96 samples were simply packaged in contact with atmospheric oxygen, while experimental samples (96 samples were packaged in a commercial vacuum (98%. All the samples were stored at 2 ± 2° C for 11 days. Analyses were performed on storage days 1, 2, 4, 7, 9, and 11. During the experiment, aw values increased in both types of packaging (in air: 0.982; vacuum-packaged: 0.989. At the end of storage, TVBN and TMA concentrations were at 28.88 ± 4.42 and 19.28 ± 3.00 g mg·100-1, respectively, in the muscle of vacuum-packaged trout; and at 30.52 ± 2.91 and 19.94 ± 2.05 mg·100 g-1, respectively, in fish in simple packaging. The FFA content in vacuum-packaged fish initially declined before increasing to 3.67 ± 2.37% of total fat as oleic acid later in the experiment. The pattern of PV changes was inconclusive, and significant changes (P -1 in vacuum-packaged fish and to 26.03 ± 8.00 mg·kg-1 in fish in simple packaging. Free fatty acids are not a good indicator of spoilage because they are converted to hydroperoxides. Vacuum packaging effectively slowed down oxidative changes in rainbow trout muscle. The peroxide content is not a suitable indicator of shelf life as peroxides are decomposed to secondary products. Total volatile basic nitrogen and thiobarbituric acid value can be recommended as suitable indicators of freshness and shelf life.

Hydrogen Peroxide Cycling in Acidic Geothermal Environments and Potential Implications for Oxidative Stress

Science.gov (United States)

Mesle, M.; Beam, J.; Jay, Z.; Bodle, B.; Bogenschutz, E.; Inskeep, W.

2014-12-01

Hydrogen peroxide (H2O2) may be produced in natural waters via photochemical reactions between dissolved oxygen, organic carbon and light. Other reactive oxygen species (ROS) such as superoxide and hydroxyl radicals are potentially formed in environments with high concentrations of ferrous iron (Fe(II), ~10-100 μM) by reaction between H2O2 and Fe(II) (i.e., Fenton chemistry). Thermophilic archaea and bacteria inhabiting acidic iron-oxide mats have defense mechanisms against both extracellular and intracellular peroxide, such as peroxiredoxins (which can degrade H2O2) and against other ROS, such as superoxide dismutases. Biological cycling of H2O2 is not well understood in geothermal ecosystems, and geochemical measurements combined with molecular investigations will contribute to our understanding of microbial response to oxidative stress. We measured H2O2 and other dissolved compounds (Fe(II), Fe(III), H2S, O2), as well as photon flux, pH and temperature, over time in surface geothermal waters of several acidic springs in Norris Geyser Basin, Yellowstone National Park, WY (Beowulf Spring and One Hundred Spring Plain). Iron-oxide mats were sampled in Beowulf Spring for on-going analysis of metatranscriptomes and RT-qPCR assays of specific stress-response gene transcription (e.g., superoxide dismutases, peroxiredoxins, thioredoxins, and peroxidases). In situ analyses show that H2O2 concentrations are lowest in the source waters of sulfidic systems (ca. 1 μM), and increase by two-fold in oxygenated waters corresponding to Fe(III)-oxide mat formation (ca. 2 - 3 μM). Channel transects confirm increases in H2O2 as a function of oxygenation (distance). The temporal dynamics of H2O2, O2, Fe(II), and H2S in Beowulf geothermal waters were also measured during a diel cycle, and increases in H2O2 were observed during peak photon flux. These results suggest that photochemical reactions may contribute to changes in H2O2. We hypothesize that increases in H2O2 and O2

Lactation Affects Isolated Mitochondria and Its Fatty Acid Composition but Has No Effect on Tissue Protein Oxidation, Lipid Peroxidation or DNA-Damage in Laboratory Mice

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Teresa G. Valencak

2016-01-01

Full Text Available Linking peak energy metabolism to lifespan and aging remains a major question especially when focusing on lactation in females. We studied, if and how lactation affects in vitro mitochondrial oxygen consumption and mitochondrial fatty acid composition. In addition, we assessed DNA damage, lipid peroxidation and protein carbonyls to extrapolate on oxidative stress in mothers. As model system we used C57BL/6NCrl mice and exposed lactating females to two ambient temperatures (15 °C and 22 °C while they nursed their offspring until weaning. We found that state II and state IV respiration rates of liver mitochondria were significantly higher in the lactating animals than in non-lactating mice. Fatty acid composition of isolated liver and heart mitochondria differed between lactating and non-lactating mice with higher n-6, and lower n-3 polyunsaturated fatty acids in the lactating females. Surprisingly, lactation did not affect protein carbonyls, lipid peroxidation and DNA damage, nor did moderate cold exposure of 15 °C. We conclude that lactation increases rates of mitochondrial uncoupling and alters mitochondrial fatty acid composition thus supporting the “uncoupling to survive” hypothesis. Regarding oxidative stress, we found no impact of lactation and lower ambient temperature and contribute to growing evidence that there is no linear relationship between oxidative damage and lactation.

Oxidative and Molecular Responses in Capsicum annuum L. after Hydrogen Peroxide, Salicylic Acid and Chitosan Foliar Applications

Science.gov (United States)

Mejía-Teniente, Laura; de Dalia Durán-Flores, Flor; Chapa-Oliver, Angela María; Torres-Pacheco, Irineo; Cruz-Hernández, Andrés; González-Chavira, Mario M.; Ocampo-Velázquez, Rosalía V.; Guevara-González, Ramón G.

2013-01-01

Hydrogen peroxide (H2O2) is an important ROS molecule (Reactive oxygen species) that serves as a signal of oxidative stress and activation of signaling cascades as a result of the early response of the plant to biotic stress. This response can also be generated with the application of elicitors, stable molecules that induce the activation of transduction cascades and hormonal pathways, which trigger induced resistance to environmental stress. In this work, we evaluated the endogenous H2O2 production caused by salicylic acid (SA), chitosan (QN), and H2O2 elicitors in Capsicum annuum L. Hydrogen peroxide production after elicitation, catalase (CAT) and phenylalanine ammonia lyase (PAL) activities, as well as gene expression analysis of cat1, pal, and pathogenesis-related protein 1 (pr1) were determined. Our results displayed that 6.7 and 10 mM SA concentrations, and, 14 and 18 mM H2O2 concentrations, induced an endogenous H2O2 and gene expression. QN treatments induced the same responses in lesser proportion than the other two elicitors. Endogenous H2O2 production monitored during several days, showed results that could be an indicator for determining application opportunity uses in agriculture for maintaining plant alert systems against a stress. PMID:23676352

Can hydrogen peroxide and quercetin improve production of ...

African Journals Online (AJOL)

The aim of the present work was to determine if hydrogen peroxide in combination with quercetin or indole butyric acid, can modify some characteristics related to rooting and development in cuttings of Eucalyptus grandis x Eucalyptus urophylla. Cuttings were periodically evaluated at 30, 60 and 90 days according to the ...

Cellulosic bioethanol production from Jerusalem artichoke (Helianthus tuberosus L.) using hydrogen peroxide-acetic acid (HPAC) pretreatment.

Science.gov (United States)

Song, Younho; Wi, Seung Gon; Kim, Ho Myeong; Bae, Hyeun-Jong

2016-08-01

Jerusalem artichoke (JA) is recognized as a suitable candidate biomass crop for bioethanol production because it has a rapid growth rate and high biomass productivity. In this study, hydrogen peroxide-acetic acid (HPAC) pretreatment was used to enhance the enzymatic hydrolysis and to effectively remove the lignin of JA. With optimized enzyme doses, synergy was observed from the combination of three different enzymes (RUT-C30, pectinase, and xylanase) which provided a conversion rate was approximately 30% higher than the rate with from treatment with RUT-C30 alone. Fermentation of the JA hydrolyzates by Saccharomyces cerevisiae produced a fermentation yield of approximately 84%. Therefore, Jerusalem artichoke has potential as a bioenergy crop for bioethanol production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of antioxidants on lipid peroxide formation in irradiated synthetic diets

International Nuclear Information System (INIS)

Wills, E.D.

1980-01-01

The effects of the antioxidants, vitamin E, propyl gallate, 2-t-butyl-4-methoxy phenol (BHA), 2,6-di-t-butyl-4-methoxy phenol (BHT), nor-dihydroguaiaretic acid (NDGA) and diphenyl-p-phenylene diamine (DPPD) in concentrations ranging between 0.001 per cent and 0.1 per cent have been tested on lipid peroxide formation in synthetic diet mixtures containing herring oil (10 per cent) mixed with starch (90 per cent) irradiated with γ-ray doses of 100 to 2000 krad. On a weight basis NDGA, DPPD, BHA and BHT were most effective and vitamin E and propyl gallate were least effective. An antioxidant concentration of 0.01 per cent normally protected against peroxide formation after a dose of 500 krad but if the dose was increased to 1000 or 2000 krad, much higher doses of antioxidant, up to 0.1 per cent, were required to give protection. Antioxidants prevented peroxide developing during post-irradiation storage even when added after irradiation. Antioxidants were partially or completely destroyed by irradiation with doses of 100 krad or more. The percentage of total antioxidant destroyed depended on the concentration; much greater destruction occurred in dilute solutions than in concentrated solutions. Vitamin E and propyl gallate were most sensitive whereas NDGA was relatively resistant. Antioxidant destruction was much enhanced if irradiation was carried out in presence of herring oil. Free radicals formed in unsaturated fatty acids of the herring oil are believed to be responsible. Lecithin and citric acid, which have been described as antioxidant synergists when added with vitamin E, caused a limited enhancement of its antioxidant action against radiation-induced peroxidation. (author)

Lipid peroxidation in liver homogenates. Effects of membrane lipid composition and irradiation

International Nuclear Information System (INIS)

Vaca, C.; Ringdahl, M.H.

1984-01-01

The rate of lipid peroxidation has been followed in whole liver homogenates from mice using the TBA-method. Liver homogenates with different membrane fatty acid composition were obtained from mice fed diets containing different sources of fat i.e. sunflower seed oil (S), coconut oil (C) and hydrogenated lard (L). The yields of the TBA-chromophore (TBA-c) were 4 times higher in the liver homogenates S compared to C and L after 4 hour incubation at 37 0 C. Irradiation of the liver homogenates before incubation inhibited the formation of lipid peroxidation products in a dose dependent way. The catalytic capacity of the homogenates was investigated, followed as the autooxidation of cysteamine or modified by addition of the metal chelator EDTA. The rate of autooxidation of cysteamine, which is dependent on the presence of metal ions (Fe/sup 2+/ or Cu/sup 2+/), was decreased with increasing dose, thus indicating an alteration in the availability of metal catalysts in the system. The addition of Fe/sup 2+/ to the system restored the lipid peroxidation yields in the irradiated systems and the presence of EDTA inhibited the formation of lipid peroxidation products in all three dietary groups. It is suggested that irradiation alters the catalytic activity needed in the autooxidation processes of polyunsaturated fatty acids

Effect of micro-encapsulated n-3 fatty acids on quality properties of two types of dry sausages

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Zdeněk Pavlík

2014-01-01

Full Text Available Dry sausages are popular traditional meat products. As these products are a rich source of animal fat, there is an effort to improve their fatty acid ratio. The aim of this work was to study the effect of micro-encapsulated n-3 fatty acids added into dry sausages. Samples of dry sausages (Poličan and Vysočina enriched with unsaturated fatty acids (36 g for 6 kg of mixture and rosemary extract (0.3 g·kg-1 were made along with control samples. Physicochemical, instrumental analyses were performed, fatty acid profile was measured by gas chromatography, and oxidation processes were monitored by determination of thiobarbituric acid reactive substances. No significant differences (P ≥ 0.05 in quality indicators were found between samples, however, there were differences in oxidation processes. Sausages enriched with unsaturated fatty acids showed an increase in thiobarbituric acid reactive substances (> 2 mg·kg-1 and > 3 mg·kg-1 in Poličan and Vysočina, respectively, compared to control. Sausages enriched with unsaturated fatty acids and also with rosemary extract have the similar concentration of thiobarbituric acid reactive substances as the control. An increase in the proportion of monounsaturated fatty acids and polyunsaturated fatty acids was seen in samples of Poličan supplemented with unsaturated fatty acids in combination with rosemary extract. The addition of rosemary extract had also a significant effect in increasing the proportion of unsaturated fatty acids in samples of Vysočina. From the viewpoint of quality indicators, changes in the properties of the product were not seen in any samples.

Lipid peroxidation and antioxidant enzymes in male infertility.

Directory of Open Access Journals (Sweden)

Dandekar S

2002-07-01

Full Text Available BACKGROUND AND AIM: Mammalian spermatozoa are rich in polyunsaturated fatty acids and are very susceptible to attack by reactive oxygen species (ROS and membrane lipid peroxide ion. Normally a balance is maintained between the amount of ROS produced and that scavenged. Cellular damage arises when this equilibrium is disturbed. A shift in the levels of ROS towards pro-oxidants in semen and vaginal secretions can induce an oxidative stress on spermatozoa. The aim was to study lipid peroxidation and antioxidant enzymes such as catalase, glutathione peroxidase and superoxide dismutase (SOD and to correlate the same, with the ′water test′, in male infertility. SETTINGS: Experimental study. SUBJECTS AND METHODS: Ejaculates from a total of 83 infertile and fertile healthy individuals were obtained. Lipid peroxidation and antioxidant enzyme levels were studied and correlated with water test. RESULTS: The results indicate that (i the antioxidant enzyme catalase showed no significant changes in the various pathological samples, (ii antioxidant enzymes SOD and glutathione peroxidase correlate positively with asthenozoospermic samples and (iii the degree of lipid peroxidation also correlates positively with the poorly swollen sperm tails. The increase in SOD and glutathione peroxidase values, in the pathological cases represents an attempt made to overcome the reactive oxygen species. CONCLUSION: Water test could be used as a preliminary marker test for sperm tail damage by reactive oxygen species, since it correlates very well with lipid peroxidation and antioxidant enzymes.

Effect of antioxidants on thiobarbituric acid reactive substances of mechanically de boned chicken meat irradiated with ionizing radiation: cobalt-60 and electron beam sources

Energy Technology Data Exchange (ETDEWEB)

Brito, Poliana de Paula; Azevedo, Heliana de; Pomarico Neto, Walter; Roque, Claudio Vitor; Brusqui, Armando Luiz, E-mail: hgomes@cnen.gov.b, E-mail: pbrito@cnen.gov.b, E-mail: cvroque@cnen.gov.b, E-mail: abrusqui@cnen.gov.b [Brazilian Nuclear Energy Commission (LAPOC/CNEN), Pocos de Caldas, MG (Brazil); Haguiwara, Marcia Mayumi Harada; Miyagusku, Luciana, E-mail: marciamh@ital.gov.b, E-mail: lucianam@ital.gov.b [Food Technology Institute (ITAL), SP (Brazil). Meat Technology Center

2011-07-01

Samples of MDCM with skin were divided into three groups: control (without antioxidants), Antioxidant 1 - A1 (0.3% Sodium Polyphosphate and Sodium Erythorbate 0.05%) and Antioxidant 2 - A2 (Rosemary Extract 0.02% and {alpha}-Tocopherol 0.01%). The three batches of samples were divided into nine groups: no antioxidant and non-irradiated (Cn/I), with antioxidant A1 and non-irradiated (A1n/I), with antioxidant A2 and non-irradiated (A2n/I) without antioxidant and irradiated in Cobalt-60 source (CCo), with antioxidant A1 irradiated in Cobalt 60 source (A1Co) with antioxidant A2 irradiated in Cobalt-60 source (A2Co) with antioxidant A1 irradiated in Electron beam (A1Eb) and with antioxidant A2 irradiated in Electron beam (A2Eb). Each 100 g sample was conditioned in a transparent, low density polyethylene oxygen permeable bag, frozen overnight at a temperature of -18 +- 1 deg C in a chamber, and irradiated in this state, maintaining the temperature low with dry ice. The samples were irradiated with a dose of 3.0 kGy, used two sources of radiation: Cobalt-60 (3.1 kGy.h{sup -1}) and electron beam (2.9 kGy.s{sup -1}). After this process, the samples were evaluated during the refrigeration period (2 +- 1 deg C) for 11 days for the following analysis: total psychotropic bacteria count, thiobarbituric acid reactive substances (TBARS). The addition of antioxidants was able to reduce lipid oxidation caused by the irradiation. There were no differences between the radiation sources used in the same parameters. The better antioxidants mixture in the TBARS reducing it was rosemary extract and {alpha}-tocopherol (A2). (author)

Effect of antioxidants on thiobarbituric acid reactive substances of mechanically de boned chicken meat irradiated with ionizing radiation: cobalt-60 and electron beam sources

International Nuclear Information System (INIS)

Brito, Poliana de Paula; Azevedo, Heliana de; Pomarico Neto, Walter; Roque, Claudio Vitor; Brusqui, Armando Luiz; Haguiwara, Marcia Mayumi Harada; Miyagusku, Luciana

2011-01-01

Samples of MDCM with skin were divided into three groups: control (without antioxidants), Antioxidant 1 - A1 (0.3% Sodium Polyphosphate and Sodium Erythorbate 0.05%) and Antioxidant 2 - A2 (Rosemary Extract 0.02% and α-Tocopherol 0.01%). The three batches of samples were divided into nine groups: no antioxidant and non-irradiated (Cn/I), with antioxidant A1 and non-irradiated (A1n/I), with antioxidant A2 and non-irradiated (A2n/I) without antioxidant and irradiated in Cobalt-60 source (CCo), with antioxidant A1 irradiated in Cobalt 60 source (A1Co) with antioxidant A2 irradiated in Cobalt-60 source (A2Co) with antioxidant A1 irradiated in Electron beam (A1Eb) and with antioxidant A2 irradiated in Electron beam (A2Eb). Each 100 g sample was conditioned in a transparent, low density polyethylene oxygen permeable bag, frozen overnight at a temperature of -18 +- 1 deg C in a chamber, and irradiated in this state, maintaining the temperature low with dry ice. The samples were irradiated with a dose of 3.0 kGy, used two sources of radiation: Cobalt-60 (3.1 kGy.h -1 ) and electron beam (2.9 kGy.s -1 ). After this process, the samples were evaluated during the refrigeration period (2 +- 1 deg C) for 11 days for the following analysis: total psychotropic bacteria count, thiobarbituric acid reactive substances (TBARS). The addition of antioxidants was able to reduce lipid oxidation caused by the irradiation. There were no differences between the radiation sources used in the same parameters. The better antioxidants mixture in the TBARS reducing it was rosemary extract and α-tocopherol (A2). (author)

K Basin Sludge Conditioning Process Testing Fate of PCBs During K Basin Sludge Dissolution in Nitric Acid and with Hydrogen Peroxide Addition

International Nuclear Information System (INIS)

Schmidt, A.J.; Thornton, B.M.; Hoppe, E.W.; Mong, G.M.; Pool, K.H.; Silvers, K.L.

1999-01-01

The work described in this report is part of the studies being performed to address the fate of polychlorinated biphenyls (PCBs) in K Basin sludge before the sludge can be transferred to the Tank Waste Remediation System (TWRS) double shell tanks. One set of tests examined the effect of hydrogen peroxide on the disposition of PCBs in a simulated K Basin dissolver solution containing 0.5 M nitric acid/1 M Fe(NO 3 ) 3 . A second series of tests examined the disposition of PCBs in a much stronger (∼10 M) nitric acid solution, similar to that likely to be encountered in the dissolution of the sludge

Algal toxicity of the alternative disinfectants performic acid (PFA), peracetic acid (PAA), chlorine dioxide (ClO2) and their by-products hydrogen peroxide (H2O2) and chlorite (ClO2-)

DEFF Research Database (Denmark)

Chhetri, Ravi Kumar; Baun, Anders; Andersen, Henrik Rasmus

2017-01-01

Environmental effect evaluation of disinfection of combined sewer overflow events with alternative chemical disinfectants requires that the environmental toxicity of the disinfectants and the main by-products of their use are known. Many disinfectants degrade quickly in water which should......: performic acid (PFA), peracetic acid (PAA) and chlorine dioxide (ClO2) as well as two by-products of their use: hydrogen peroxide (H2O2) and chlorite. All of the five chemicals investigated showed clear toxicity to the algae with well-defined dose response curves. The EC50 values ranged from 0.16 to 2.9 mg...

Effects of bisphenol A on the metabolisms of active oxygen species in mouse tissues

International Nuclear Information System (INIS)

Kabuto, H.; Hasuike, S.; Minagawa, N.; Shishibori, T.

2003-01-01

We investigated the modifications in endogenous antioxidant capacity, including superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase, oxidative stress index, reduced glutathione (GSH), glutathione disulfide (GSSG), and thiobarbituric acid-reactive substance (TBARS) in the brain, liver, kidney, and testes of mice under bisphenol A (BPA), an endocrine disrupter, treated for 5 days. BPA was administrated intraperitoneally at doses of 25 and 50 mg/kg/day. The TBARS levels were not affected by BPA administrations. The SOD activities increased and the catalase activities decreased in the liver after BPA administration. The GPx activity decreased in the kidney. The levels of GSH+GSSG increased in the brain, kidney, liver, and testes, while, the levels of GSH decreased in the testes. SOD converts superoxide into hydrogen peroxide, and catalase and GPx convert hydrogen peroxide into hydrogen oxide. Our results suggest that the injection of BPA induces overproduction of hydrogen peroxide in the mouse organs. Hydrogen peroxide is easily converted to hydroxy radical. The decrease of GSH and the increase of GSSG may be caused by the hydroxy radical. BPA may show its toxicity by increasing hydrogen peroxide

Production of uranium peroxide

International Nuclear Information System (INIS)

Caropreso, F.E.; Kreuz, D.F.

1977-01-01

A process is claimed of recovering uranium values as uranium peroxide from an aqueous uranyl solution containing dissolved vanadium and sodium impurities by treating the uranyl solution with hydrogen peroxide in an amount sufficient to have an excess of at least 0.5 parts H 2 O 2 per part of vanadium (V 2 O 5 ) above the stoichiometric amount required to form the uranium peroxide, the hydrogen peroxide treatment is carried out in three sequential phases consisting of I, a precipitation phase in which the hydrogen peroxide is added to the uranyl solution to precipitate the uranium peroxide and the pH of the reaction medium maintained in the range of 2.5 to 5.5 for a period of from about 1 to 60 minutes after the hydrogen peroxide addition; II, a digestion phase in which the pH of the reaction medium is maintained in the range of 3.0 to 7.0 for a period of about 5 to 180 minutes and III, a final phase in which the pH of the reaction medium is maintained in the range of 4.0 to 7.0 for a period of about 1 to 60 minutes during which time the uranium peroxide is separated from the reaction solution containing the dissolved vanadium and sodium impurities. The excess hydrogen peroxide is maintained during the entire treatment up until the uranium peroxide is separated from the reaction medium

Safer operating conditions and optimal scaling-up process for cyclohexanone peroxide reaction

International Nuclear Information System (INIS)

Zang, Na; Qian, Xin-Ming; Liu, Zhen-Yi; Shu, Chi-Min

2015-01-01

Highlights: • Thermal hazard of cyclohexanone peroxide reaction was measured by experimental techniques. • Levenberg–Marquardt algorithm was adopted to evaluate kinetic parameters. • Safer operating conditions at laboratory scale were acquired by BDs and TDs. • The verified safer operating conditions were used to obtain the optimal scale-up parameters applied in industrial plants. - Abstract: The cyclohexanone peroxide reaction process, one of the eighteen hazardous chemical processes identified in China, is performed in indirectly cooled semibatch reactors. The peroxide reaction is added to a mixture of hydrogen peroxide and nitric acid, which form heterogeneous liquid–liquid systems. A simple and general procedure for building boundary and temperature diagrams of peroxide process is given here to account for the overall kinetic expressions. Such a procedure has been validated by comparison with experimental data. Thermally safer operating parameters were obtained at laboratory scale, and the scaled-up procedure was performed to give the minimum dosing time in an industrial plant, which is in favor of maximizing industrial reactor productivity. The results are of great significance for governing the peroxide reaction process apart from the thermal runaway region. It also greatly aids in determining optimization on operating parameters in industrial plants.

Assessment of lipid and protein peroxidation markers in non-pregnant and pregnant female dogs.

Science.gov (United States)

Szczubiał, M; Kankofer, M; Dąbrowski, R; Bochniarz, M; Urban-Chmiel, R

2015-01-01

The aim of the study was to investigate oxidative stress during normal pregnancy in female dogs based on an evaluation of plasma markers for lipid and protein peroxidation. Twenty clinically healthy female dogs (10 non-pregnant and 10 pregnant) were used in the study. Blood samples from the pregnant animals were collected at 19-21, 38-40, and 56-58 days of pregnancy. Blood samples from non-pregnant female dogs were obtained between 20 and 35 days after ineffective breeding. As indicators of oxidative stress, we measured the following using spectrophotometric and spectrof- luorimetric methods: thiobarbituric acid reactive substances (TBARS), radical cations of N,N, diethylparaphenylene diamine (RC-DEPPD), sulfhydryl groups (SH groups), bityrosine and formylkynurenine. The mean plasma TBARS concentration in the pregnant dogs (0.486 ± 0.071-0.581 ± 0.191 μmol/g protein) was significantly higher (p pregnant animals (0.274 ± 0.111 μmol/g protein). A marked, although not significant, decrease in SH group content, as well as an increase in bityrosine and formylkynurenine concentration were concurrently observed in the pregnant dogs. No significant differences were found in terms of the studied markers in the pregnant animals when comparing the values obtained during the investigated periods of pregnancy, although there was a progressive decrease in TBARS concentration and a progressive increase in RC-DEPPD, bityrosine and formylkynurenine contents. Our findings suggest that normal pregnancy in female dogs is associated with oxidative stress. Further studies are necessary to establish the physiological ranges of antioxidative/oxidative profiles in pregnant dogs and to explain if and how the intensity of oxidative stress might contribute to the risk of the complications of pregnancy.

Sol – Gel synthesis and characterization of magnesium peroxide nanoparticles

International Nuclear Information System (INIS)

Jaison, J; Chan, Y S; Ashok raja, C; Balakumar, S

2015-01-01

Magnesium peroxide is an excellent source of oxygen in agriculture applications, for instance it is used in waste management as a material for soil bioremediation to remove contaminants from polluted underground water, biological wastes treatment to break down hydrocarbon, etc. In the present study, sol-gel synthesis of magnesium peroxide (MgO 2 ) nanoparticles is reported. Magnesium peroxide is odourless; fine peroxide which releases oxygen when reacts with water. During the sol-gel synthesis, the magnesium malonate intermediate is formed which was then calcinated to obtain MgO 2 nanoparticles. The synthesized nanoparticles were characterized using Thermo gravimetric -Differential Thermal Analysis (TG- DTA), X-Ray Diffraction studies (XRD) and High Resolution Transmission Electron Microscope (HRTEM). Our study provides a clear insight that the formation of magnesium malonate during the synthesis was due to the reaction between magnesium acetate, oxalic acid and ethanol. In our study, we can conclude that the calcination temperature has a strong influence on particle size, morphology, monodispersity and the chemistry of the particles. (paper)

DMSO does not protect against hydroxyl radical induced peroxidation in model membranes

Energy Technology Data Exchange (ETDEWEB)

Raleigh, J A; Kremers, W [Atomic Energy of Canada Ltd., Pinawa, Manitoba. Whiteshell Nuclear Research Establishment

1981-04-01

Dimethylsulphoxide (DMSO) promoted peroxidation in both linolenate and linoleate micelles. The promotional effect was most evident at concentrations of DMSO above 0.3 M with 0.012 M fatty acid. This was well above the DMSO concentration at which all the OH was scavenged by DMSO on the basis of the relative rate constants recorded. It was also found that DMSO did not decrease the yield of lipid hydroperoxide in a concentration range (0.01 to 0.1 M) where DMSO scavenges OH in competition with the unsaturated fatty acids. The sustaining mechanism could be accounted for in terms of CHsup(.)/sub 3/ and CH/sub 3/OOsup(.) being as effective as OH in initiating lipid peroxidation. A possible alternative explanation for the absence of protection by DMSO is that OH scavenging by DMSO is equivalent to lowering the dose-rate. The promotion of peroxidation at high DMSO concentration (> 1.0 M) was more difficult to account for, but may be analogous to the promotional effect of caesium and rubidium counterions.

An Effective Ostrich Oil Bleaching Technique Using Peroxide Value as an Indicator

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Gan Seng Chiew

2011-07-01

Full Text Available Ostrich oil has been used extensively in the cosmetic and pharmaceutical industries. However, rancidity causes undesirable chemical changes in flavour, colour, odour and nutritional value. Bleaching is an important process in refining ostrich oil. Bleaching refers to the removal of certain minor constituents (colour pigments, free fatty acid, peroxides, odour and non-fatty materials from crude fats and oils to yield purified glycerides. There is a need to optimize the bleaching process of crude ostrich oil prior to its use for therapeutic purposes. The objective of our study was to establish an effective method to bleach ostrich oil using peroxide value as an indicator of refinement. In our study, we showed that natural earth clay was better than bentonite and acid-activated clay to bleach ostrich oil. It was also found that 1 hour incubation at a 150 °C was suitable to lower peroxide value by 90%. In addition, the nitrogen trap technique in the bleaching process was as effective as the continuous nitrogen flow technique and as such would be the recommended technique due to its cost effectiveness.

Reactivity of lignin and lignin models towards UV-assisted peroxide

International Nuclear Information System (INIS)

Sun, Y.P.; Wallis, A.F.A.; Nguyen, K.L.

1997-01-01

The comparative reactivities of a series of guaiacyl and syringyl lignin model compounds and their methylated analogues towards alkaline peroxide and UV-alkaline peroxide were investigated. The overall reaction was followed by monitoring the reduction of the substrate as a function of time, and in every case, the reaction showed pseudo-first-order kinetics. The reaction rates of most lignin models having identical sidechains with alkaline peroxide and with UV-alkaline peroxide were in the order syringyl guaiacyl 3,4,5-trimethoxyphenyl veratryl. Thus phenols react faster than their methyl ethers, and an extra ortho methoxyl group promotes the reaction. Lignin models possessing electron-donating sidechains had generally higher reaction rates than those with electron-withdrawing sidechains. The reaction rates of the series of benzoic acids were 2-4 times higher at pH 11 than at pH 5. UV-peroxide degradation of a eucalypt kraft lignin was faster than that of a pine kraft lignin, and degradation was 1.4-1.6 times faster at pH 11 than at pH 5. The data are consistent with the formation of higher amounts of reactive radicals under alkaline conditions, and aromatic rings with greater electronegativities promoting reactions with the radicals

Influence of Growth Medium on Hydrogen Peroxide and Bacteriocin Production of Lactobacillus Strains

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Edina Németh

2005-01-01

Full Text Available This study was conducted to investigate the inhibitory effect of bacteriocin and the production of hydrogen peroxide by four non-starter lactic acid bacteria, Lactobacillus plantarum 2142, Lactobacillus curvatus 2770, Lactobacillus curvatus 2775, Lactobacillus casei subsp. pseudoplantarum 2750 and the probiotic strain Lactobacillus casei Shirota, propagated in de Man Rogosa Sharpe (MRS and tomato juice (TJ broth. The methods were a commonly used agar diffusion technique and a microtiter assay method. The best peroxide-producing Lactobacillus strain was selected for screening the inhibitory activity against Listeria monocytogenes, Bacillus cereus, Escherichia coli and the activity of bacteriocins against Lactobacillus sakei and Candida glabrata. All of the investigated lactic acid bacteria (LAB strains grown in MRS broth produced the highest concentration of hydrogen peroxide ranging from 2–6 g/mL after 72 h of storage. L. plantarum 2142 produced enough hydrogen peroxide already after 24 h at 5 °C in phosphate buffer to inhibit the growth of L. monocytogenes and B. cereus. Crude bacteriocin suspension from the investigated LAB inhibited only slightly the growth of L. sakei, however, the same suspension from MRS completely inhibited the 6-fold diluted yeast suspension. The concentrated bacteriocin suspensions from the both broths inhibited the growth of L. sakei completely. Among the strains, L. plantarum 2142 seemed to be the best peroxide and bacteriocin producer, and the antimicrobial metabolite production was better in MRS than in TJ broth.

Mechanism of Sporicidal Activity for the Synergistic Combination of Peracetic Acid and Hydrogen Peroxide.

Science.gov (United States)

Leggett, Mark J; Schwarz, J Spencer; Burke, Peter A; McDonnell, Gerald; Denyer, Stephen P; Maillard, Jean-Yves

2016-02-15

There is still great interest in controlling bacterial endospores. The use of chemical disinfectants and, notably, oxidizing agents to sterilize medical devices is increasing. With this in mind, hydrogen peroxide (H2O2) and peracetic acid (PAA) have been used in combination, but until now there has been no explanation for the observed increase in sporicidal activity. This study provides information on the mechanism of synergistic interaction of PAA and H2O2 against bacterial spores. We performed investigations of the efficacies of different combinations, including pretreatments with the two oxidizers, against wild-type spores and a range of spore mutants deficient in the spore coat or small acid-soluble spore proteins. The concentrations of the two biocides were also measured in the reaction vessels, enabling the assessment of any shift from H2O2 to PAA formation. This study confirmed the synergistic activity of the combination of H2O2 and PAA. However, we observed that the sporicidal activity of the combination is largely due to PAA and not H2O2. Furthermore, we observed that the synergistic combination was based on H2O2 compromising the spore coat, which was the main spore resistance factor, likely allowing better penetration of PAA and resulting in the increased sporicidal activity. Copyright © 2016 Leggett et al.

Antioxidative role of ocular melanin pigment in the model of lens induced uveitis.

Science.gov (United States)

Bilgihan, A; Bilgihan, M K; Akata, R F; Aricioğlu, A; Hasanreisoğlu, B

1995-12-01

Ocular melanin pigment has antioxidant effect against excess of dispersed light. To investigate whether it has a similar effect in ocular inflammations, we used albino and pigmented guinea pigs and measured retinal glutathione peroxidase activities and lipid peroxide levels (expressed as thiobarbituric acid reactive substances) in a model of lens induced uveitis. Although the increase in the levels of the retinal lipid peroxides were higher in the albino group (204%, p < 0.05), the decrease in the activities of glutathione peroxidase were higher in pigmented guinea pigs (26%, p < 0.005). The results of the study suggest that pigmentless animals are more sensitive to the ocular inflammations, and ocular melanin pigment may act as an endojen antioxidant in lens induced uveitis.

Radappertization of ready-to-eat shelf-stable, traditional Indian bread - Methi Paratha

Science.gov (United States)

Bhoir, Shraddha A.; Muppalla, Shobita R.; Kanatt, Sweetie R.; Chawla, S. P.; Sharma, Arun

2015-06-01

Shelf-stable ready-to-eat (RTE) Methi Paratha (flavored Indian unleavened flat bread) was developed using combination of hurdles including radiation processing. The Methi Paratha was prepared using dough containing wheat flour, dried fenugreek leaves and spices. The samples were vacuum packed in multi-layered pouches and irradiated at 25 kGy in frozen conditions. Samples were evaluated for microbiological counts, lipid peroxidation and sensory attributes during storage under ambient conditions. Samples were found to be devoid of any viable microorganism throughout the storage period of 180 days. The thiobarbituric acid reactive substances (TBARS) value which indicates lipid peroxidation of samples did not show any significant increase with time. The Methi Paratha was found to be acceptable by the evaluating panelists.

The Effect of Buckwheat Hull Extract on Lipid Oxidation in Frozen-Stored Meat Products.

Science.gov (United States)

Hęś, Marzanna; Szwengiel, Artur; Dziedzic, Krzysztof; Le Thanh-Blicharz, Joanna; Kmiecik, Dominik; Górecka, Danuta

2017-04-01

This study investigated the effect of antioxidants on lipid stability of frozen-stored meat products. Buckwheat hull extract was used to enrich fried meatballs made from ground pork. During 180-d storage of meat products, lipid oxidation (peroxide and 2-thiobarbituric acid reactive substances [TBARS] value) was periodically monitored. The results were compared with butylated hydroxytoluene (BHT). The addition of antioxidants decreased lipid oxidation in stored meatballs. The highest ability to control peroxide and TBARS values was demonstrated for buckwheat hull extract. Moreover, buckwheat hull extract showed a higher 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity as well as higher Fe(II) ion chelating ability, as compared with BHT. The total content of phenolic compounds are highly correlated to the individual polyphenols in extract of buckwheat hull, among which the following were assayed: 3,4-dihydroxybenzoic acid, 4-hydroxybenzoic acid, gallic acid, isovanillic acid and p-coumaric acid, and flavonoids: isoorientin, quercetin, quercetin 3-d-glucoside, rutin, and vitexin. These results indicate that plant extracts can be used to prolong shelf life of products by protecting them against lipid oxidation and deterioration of their nutritional quality. © 2017 Institute of Food Technologists®.

Influence of feeding thermally peroxidized soybean oil to finishing barrows on processing characteristics and shelf life of commercially manufactured bacon.

Science.gov (United States)

Overholt, M F; Lowell, J E; Kim, G D; Boler, D D; Kerr, B J; Dilger, A C

2018-05-12

Objectives were to evaluate effects of feeding soybean oil (SO) with varying levels of peroxidation on fresh belly characteristics, processing yields, and shelf life of commercially manufactured bacon stored under food-service style conditions. Fifty-six barrows were randomly assigned to 1 of 4 diets containing 10% fresh SO (22.5°C) or thermally processed SO (45°C for 288 h, 90°C for 72 h, or 180°C for 6 h), each infused with air at a rate of 15L/min. Individually housed pigs were provided ad libitum access to feed for 81 d. On d 82 pigs were slaughtered and on d 83 carcasses were fabricated and bellies collected for recording of weight, dimensions, and flop distance. Belly adipose tissue cores were collected for analysis of iodine value (IV) by near-infrared spectroscopy (NIR-IV). Bacon was manufactured at a commercial processing facility and sliced bacon was subsequently transferred to food-service style packaging and subjected to 0, 30, 60, or 90 d storage at -20°C. Stored bacon was evaluated for thiobarbituric acid reactive substances (TBARS) and trained sensory evaluation of oxidized odor and flavor. Fresh belly and bacon processing traits were analyzed as a one-way ANOVA with the fixed effect of SO; whereas, shelf life traits were analyzed as a one-way ANOVA repeated in time. There was no effect (P ≥ 0.30) of SO on belly weight, length, width, or thickness; but bellies of pigs fed 90°C SO had greater (P ≤ 0.04) flop distance (more firm) than all other SO treatments. Belly fat NIR-IV of pigs fed 90°C SO were 10.22 units less (P processed at 90°C and 180°C reduced belly adipose tissue IV, but feeding peroxidized SO did not affect processing yields or shelf life characteristics of commercially manufactured bacon.

Teste de TBA aplicado a carnes e derivados: métodos tradicionais, modificados e alternativos TBA test applied to meats and their products: traditional, modified and alternative methods

Directory of Open Access Journals (Sweden)

Cibele Cristina Osawa

2005-08-01

Full Text Available The TBA test is essential to quality control of fat-containing food, being the test most applied to evaluate lipid peroxidation in fishery, meat and poultry products. It estimates malonaldehyde, a secondary oxidation product, by reacting with 2-thiobarbituric acid, forming a coloured complex, measured spectrophotometrically atlambda = 532 nm. Results are expressed as mg malonaldehyde per kg sample or frequently as "TBA value". There are four ways of quantifying it: by lipid extraction, direct heating, distillation or heat-acid extraction. This review intends to point out traditional, modified and alternative TBA test methods, besides enumerating advantages and drawbacks of each one.

Crystal structure of rubidium peroxide ammonia disolvate

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Tobias Grassl

2017-02-01

Full Text Available The title compound, Rb2O2·2NH3, has been obtained as a reaction product of rubidium metal dissolved in liquid ammonia and glucuronic acid. As a result of the low-temperature crystallization, a disolvate was formed. To our knowledge, only one other solvate of an alkali metal peroxide is known: Na2O2·8H2O has been reported by Grehl et al. [Acta Cryst. (1995, C51, 1038–1040]. We determined the peroxide bond length to be 1.530 (11 Å, which is in accordance with the length reported by Bremm & Jansen [Z. Anorg. Allg. Chem. (1992, 610, 64–66]. One of the ammonia solvate molecules is disordered relative to a mirror plane, with 0.5 occupancy for the corresponding nitrogen atom.

Antioxidant activities of various fruits and vegetables produced in Taiwan.

Science.gov (United States)

Huang, Hui-Yu; Chang, Chen-Kang; Tso, Tim K; Huang, Ju-Jen; Chang, Wei-Wei; Tsai, Ying-Chieh

2004-08-01

Fruits and vegetables have been known to contain a variety of antioxidant components. It has been suggested that antioxidants may protect biomolecules from oxidative damage and therefore be associated with reduced risks of cardiovascular disease and certain cancer. The antioxidant abilities of various parts of eight common fruits and vegetables produced in Taiwan were investigated, including tomato, guava, squash, tangerine, wax gourd, pineapple, chayote, and eggplant. Squash, wax gourd, tomato, and guava seeds showed the highest antioxidant activities in thiobarbituric acid assay. Wax guard and squash seeds showed the highest antioxidant activities in iodometric assay. At the level of 1 g fresh sample, low-density lipoprotein peroxidation was inhibited by at least 90% by tomato meat, guava meat, squash seed, wax gourd meat, core, and seed, and eggplant skin. The total phenolic content was significantly correlated with antioxidant activities measured by thiobarbituric acid (r=0.715, P<0.01) and iodometric (r=0.749, P<0.01) assays. The results of this study could be used for development of merchandise with potential health benefits from agricultural products.

Chemical composition and antibacterial activity of oils from Chrysicthys nigrodigitatus and Hepsetus odoe, two freshwater fishes from Yabassi, Cameroon.

Science.gov (United States)

Simplice, Mouokeu Raymond; Macaire, Womeni Hilaire; Hervé, Njike Ngamga Fabrice; Fabrice, Tonfack Djikeng; Justin, Djopnang DJimbie; François, Tchoumbougnang; Jules-Roger, Kuiate

2018-03-12

Oils of fish origin are a very rich source of Omega - 3 and Omega - 6 fatty acids. They have been suggested to provide numerous health benefits for humans involving antimicrobial properties. Chrysichthys nigrodigitatus and Hepsetus odoe are two fishes well known in Cameroon. The chemical composition and the antibacterial activity of these fishes derived oils are unknown. The study was designed to valorise C. nigrodigitatus and H.s odoe oils activity against food poisoning bacteria. Oils were extracted by pressing and maceration methods. Their quality was assessed by analysing quality indexes including peroxides, acid, iodine, anisidine and thiobarbituric acid values. Chemical analysis was established by gas chromatography coupled to flame ionization detector. Antibacterial activity was evaluated by broth microdilution method. C. nigrodigitatus oil obtained by maceration exhibited highest acid (7.33 ± 0.00 mg KOH/g), anisidine (34.5 ± 1.84) and thiobarbituric acid (7.50 ± 0.30 μmol MDA/Kg) values compared to that obtained by pressing method (9.13 ± 0.64 and 6.72 ± 0.34 μmol MDA/Kg) respectively. H. odoe oil obtained by pressing method showed highest peroxide value (6.22 ± 1.31 meq O 2 /kg). Oil chemical analysis revealed long chain polyunsaturated fatty acids of the ω-3 family: linolenic acid (C18:3); eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) and ω-6 family; arachidonic acid (C20:4). In addition, C. nigrodigitatus oil obtained by pressing and maceration methods showed Minimum Inhibitory Concentrations (MIC) values ranging from 32 to 64 mg/ml. H. odoe oil obtained by pressing method revealed MIC values ranging between 8 and 64 mg/ml. C. nigrodigitatus and H. odoe oils have activity against food poisoning bacteria, due to their chemical composition.

Effects of Loud Noise on Oxidation and Lipid peroxidation Variations of Liver Tissue of Rabbit

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Mirzaei Ramazan

2009-06-01

Full Text Available Background: In today's world, noise is one of the major physical pollutants. The exact mechanism leading to tissue damage in loud noise is not clear. There are increasing evidences that show damage to cochlear tissue by noise is linked to cell injury induced by free radical species. The aim of this study was to investigate the relationship between change in liver tissue glutathione (anti- oxidant and malondialdehyde (one metabolite of lipid oxidation levels that occur in rabbits which were exposed to continuous loud noise.Materials and Methods: This experimental study was performed on 12 white Newzeland male rabbits in Tarbiat Modarres University in 2004. The rabbits were assigned to the following two groups: control, and exposed to continuous loud noise for 96 hours (8 h/day for 12 days, SPL=110dBA and 250Hz to 20 KHz. The concentration of malondialdehyde (MDA and glutathione (GSH in liver tissue samples were measured in rabbits after exposure to noise. Thiobarbituric acid reacting substance, Ellman's reagent and spectrophotometry techniques were used for this measurement. The data were statically analyzed by SPSS software and 2 groups were compared by t-test. Differences at the level of P<0.05 were considered statistically significant.Results: Comparison of the biochemical parameters of GSH and MDA measured in treated group with control indicated that antioxidant and lipid peroxidants parameters were suppressed in treated group compared to control group (p<0.05.Conclusion: Possible similarities between rabbit and human biological system indicate the possible role of noise in causation of oxidative stress in context with liver tissue impairm

Polyphenols of Salix aegyptiaca modulate the activities of drug metabolizing and antioxidant enzymes, and level of lipid peroxidation.

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Nauman, Mohd; Kale, R K; Singh, Rana P

2018-03-07

Salix aegyptiaca is known for its medicinal properties mainly due to the presence of salicylate compounds. However, it also contains other beneficial phytochemicals such as gallic acid, quercetin, rutin and vanillin. The aim of the study was to examine the redox potential, antioxidant and anti-inflammatory activity of these phytochemicals along with acetylsalicylic acid. The redox potential and antioxidant activity of gallic acid, quercetin, rutin, vanillin and acetylsalicylic acid were determined by oxidation-reduction potential electrode method and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, respectively. In ex vivo studies, antioxidant activity of these phytochemicals was determined by lipid peroxidation and carbonyl content assay in the liver of mice. Anti-inflammatory activity was determined by protein denaturation method. Six-week old C57BL/6 mice treated with gallic acid (100 mg/kg body weight) and acetylsalicylic acid (25 and 50 mg/kg body weight) to investigate their in vivo modulatory effects on the specific activities of drug metabolizing phase I and phase II enzymes, antioxidant enzymes and level of lipid peroxidation in liver. The order of ability to donate electron and antioxidant activity was found to be: gallic acid > quercetin > rutin > vanillin > acetylsalicylic acid. In ex vivo studies, the similar pattern and magnitude of inhibitory effects of these phytochemicals against peroxidative damage in microsomes and protein carbonyl in cytosolic fraction were observed. In in vivo studies, gallic acid and acetylsalicylic acid alone or in combination, enhanced the specific activities of drug metabolizing phase I and phase II enzymes as well as antioxidant enzymes and also inhibited lipid peroxidation in liver. These findings show a close link between the electron donation and antioxidation potential of these phytochemicals, and in turn their biological activity. Gallic acid, quercetin, rutin and vanillin were found to be better electron donors and

Spectroscopic studies on the antioxidant activity of p-coumaric acid

Science.gov (United States)

Kiliç, Ismail; Yeşiloğlu, Yeşim

2013-11-01

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

Sulfuric acid and hydrogen peroxide surface passivation effects on AlGaN/GaN high electron mobility transistors

Energy Technology Data Exchange (ETDEWEB)

Zaidi, Z. H., E-mail: zaffar.zaidi@sheffield.ac.uk; Lee, K. B.; Qian, H.; Jiang, S.; Houston, P. A. [Department of Electronic and Electrical Engineering, The University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom); Guiney, I.; Wallis, D. J.; Humphreys, C. J. [Department of Materials Science and Metallurgy, The University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS (United Kingdom)

2014-12-28

In this work, we have compared SiN{sub x} passivation, hydrogen peroxide, and sulfuric acid treatment on AlGaN/GaN HEMTs surface after full device fabrication on Si substrate. Both the chemical treatments resulted in the suppression of device pinch-off gate leakage current below 1 μA/mm, which is much lower than that for SiN{sub x} passivation. The greatest suppression over the range of devices is observed with the sulfuric acid treatment. The device on/off current ratio is improved (from 10{sup 4}–10{sup 5} to 10{sup 7}) and a reduction in the device sub-threshold (S.S.) slope (from ∼215 to 90 mV/decade) is achieved. The sulfuric acid is believed to work by oxidizing the surface which has a strong passivating effect on the gate leakage current. The interface trap charge density (D{sub it}) is reduced (from 4.86 to 0.90 × 10{sup 12 }cm{sup −2} eV{sup −1}), calculated from the change in the device S.S. The gate surface leakage current mechanism is explained by combined Mott hopping conduction and Poole Frenkel models for both untreated and sulfuric acid treated devices. Combining the sulfuric acid treatment underneath the gate with the SiN{sub x} passivation after full device fabrication results in the reduction of D{sub it} and improves the surface related current collapse.

Sulfuric acid and hydrogen peroxide surface passivation effects on AlGaN/GaN high electron mobility transistors

International Nuclear Information System (INIS)

Zaidi, Z. H.; Lee, K. B.; Qian, H.; Jiang, S.; Houston, P. A.; Guiney, I.; Wallis, D. J.; Humphreys, C. J.

2014-01-01

In this work, we have compared SiN x passivation, hydrogen peroxide, and sulfuric acid treatment on AlGaN/GaN HEMTs surface after full device fabrication on Si substrate. Both the chemical treatments resulted in the suppression of device pinch-off gate leakage current below 1 μA/mm, which is much lower than that for SiN x passivation. The greatest suppression over the range of devices is observed with the sulfuric acid treatment. The device on/off current ratio is improved (from 10 4 –10 5 to 10 7 ) and a reduction in the device sub-threshold (S.S.) slope (from ∼215 to 90 mV/decade) is achieved. The sulfuric acid is believed to work by oxidizing the surface which has a strong passivating effect on the gate leakage current. The interface trap charge density (D it ) is reduced (from 4.86 to 0.90 × 10 12  cm −2 eV −1 ), calculated from the change in the device S.S. The gate surface leakage current mechanism is explained by combined Mott hopping conduction and Poole Frenkel models for both untreated and sulfuric acid treated devices. Combining the sulfuric acid treatment underneath the gate with the SiN x passivation after full device fabrication results in the reduction of D it and improves the surface related current collapse

Enzyme catalytic resonance scattering spectral detection of trace hydrogen peroxide using guaiacol as substrate

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Shiwen Huang

2011-08-01

Full Text Available Hydrogen peroxide oxidized guaiacol to form tetramer particles that exhibited a strong resonance scattering (RS peak at 530 nm in the presence of horseradish peroxidase (HRP in citric acid-Na2HPO4 buffer solution of pH 4.4. The RS peak increased when the concentration of hydrogen peroxide increased. The increased RS intensity (ΔI530 nm was linear to the hydrogen peroxide concentration in the range of 0.55-27.6 μM, with a linear regression equation of ΔI530 nm = 17.1C + 1.6, a relative coefficient of 0.9996 and a detection limit of 0.03 μM H2O2. This proposed method was applied to detect hydrogen peroxide in rain water, with sensitivity, selectivity, rapidity, and recovery of 98.0-104 %.

Peroxide organometallic compounds and their transformations

International Nuclear Information System (INIS)

Razuvaev, G.A.; Brilkina, T.G.

1976-01-01

A survey is given experimental works on synthesis and reactions of peroxide organometallic compounds. Reactions have been considered of organometallic compounds with oxygen and organic peroxides which result in formation of both peroxide and non-peroxide products. Possible routes and mechanisms of chemical transformations of peroxide organometallic compounds have been discussed. Reactions of organometallic compounds with oxygen and peroxides have been considered

Free radical derivatives formed from cyclooxygenase-catalyzed dihomo-γ-linolenic acid peroxidation can attenuate colon cancer cell growth and enhance 5-fluorouracil's cytotoxicity.

Science.gov (United States)

Xu, Yi; Qi, Jin; Yang, Xiaoyu; Wu, Erxi; Qian, Steven Y

2014-01-01

Dihomo-γ-linolenic acid (DGLA) and its downstream fatty acid arachidonic acid (AA) are both nutritionally important ω-6 polyunsaturated fatty acids (ω-6s). Evidence shows that, via COX-mediated peroxidation, DGLA and its metabolites (1-series prostaglandins) are associated with anti-tumor activity, while AA and its metabolites (2-series prostaglandins) could be tightly implicated in various cancer diseases. However, it still remains a mystery why DGLA and AA possess contrasting bioactivities. Our previous studies showed that DGLA could go through an exclusive C-8 oxygenation pathway during COX-catalyzed lipid peroxidation in addition to a C-15 oxygenation pathway shared by both DGLA and AA, and that the exclusive C-8 oxygenation could lead to the production of distinct DGLA׳s free radical derivatives that may be correlated with DGLA׳s anti-proliferation activity. In the present work, we further investigate the anti-cancer effect of DGLA׳s free radical derivatives and their associated molecular mechanisms. Our study shows that the exclusive DGLA׳s free radical derivatives from C-8 oxygenation lead to cell growth inhibition, cell cycle arrest and apoptosis in the human colon cancer cell line HCA-7 colony 29, probably by up-regulating the cancer suppressor p53 and the cell cycle inhibitor p27. In addition, these exclusive radical derivatives were also able to enhance the efficacy of 5-Fluorouracil (5-FU), a widely used chemo-drug for colon cancer. For the first time, we show how DGLA׳s radical pathway and metabolites are associated with DGLA׳s anti-cancer activities and able to sensitize colon cancer cells to chemo-drugs such as 5-FU. Our findings could be used to guide future development of a combined chemotherapy and dietary care strategy for colon cancer treatment.

A novel flow battery: A lead acid battery based on an electrolyte with soluble lead(II). Part IX: Electrode and electrolyte conditioning with hydrogen peroxide

Science.gov (United States)

Collins, John; Li, Xiaohong; Pletcher, Derek; Tangirala, Ravichandra; Stratton-Campbell, Duncan; Walsh, Frank C.; Zhang, Caiping

Extended cycling of a soluble lead acid battery can lead to problems due to an imbalance in the coulombic efficiency leading to deposits of Pb and PbO2 on the electrodes. Periodic addition of hydrogen peroxide to the electrolyte of the soluble lead acid flow battery largely overcomes several operational problems seen during extended cycling, using a 10 cm × 10 cm parallel plate flow cell. It is shown that this treatment greatly extends the number of cycles that can be achieved with a reasonable energy-, voltage-, and charge efficiency of 54-66%, 71%, and 77-91%.

A novel flow battery: A lead acid battery based on an electrolyte with soluble lead(II). Part IX: Electrode and electrolyte conditioning with hydrogen peroxide

Energy Technology Data Exchange (ETDEWEB)

Collins, John; Stratton-Campbell, Duncan [C-Tech Innovation Ltd., Capenhurst, Chester CH1 6EH (United Kingdom); Li, Xiaohong; Tangirala, Ravichandra; Walsh, Frank C.; Zhang, Caiping [Energy Technology Research Group, School of Engineering Sciences, University of Southampton, Highfield, University Road, Southampton SO17 1BJ (United Kingdom); Pletcher, Derek [Electrochemistry and Surface Science Group, School of Chemistry, University of Southampton, Southampton SO17 1BJ (United Kingdom)

2010-05-01

Extended cycling of a soluble lead acid battery can lead to problems due to an imbalance in the coulombic efficiency leading to deposits of Pb and PbO2 on the electrodes. Periodic addition of hydrogen peroxide to the electrolyte of the soluble lead acid flow battery largely overcomes several operational problems seen during extended cycling, using a 10 cm x 10 cm parallel plate flow cell. It is shown that this treatment greatly extends the number of cycles that can be achieved with a reasonable energy-, voltage-, and charge efficiency of 54-66%, 71%, and 77-91%. (author)

Lipolysis, lipid peroxidation, and color characteristics of Serrano Hams from Duroc and large white pigs during dry-curing.

Science.gov (United States)

del Olmo, Ana; Calzada, Javier; Nuñez, Manuel

2013-11-01

Lipolysis, lipid peroxidation, and colorimetric characteristics of Serrano hams from Duroc and Large White pigs along a 15-mo curing period were investigated. Physicochemical parameters of both types of hams evolved similarly during curing. Twelve of 13 free fatty acids (FFAs) increased during curing, eicosatrienoic acid being the only exception. Linoleic, stearic, and arachidonic acids and the minor heptadecanoic acid reached lower concentrations, and the rest of minor FFAs higher concentrations, in Duroc hams than in Large White hams. The index measuring the early stage of lipid peroxidation declined from month 5 onwards, indicating that the phenomenon had been completed by month 5, while the index of the secondary stage of lipid peroxidation increased with curing time. Higher values were found for the 1st index in Duroc hams. Curing affected color parameters. Lightness decreased and redness increased in both types of hams, while yellowness decreased only in Duroc hams. Lower redness values were found for Duroc hams. Major differences in color parameters were found between muscles. Principal components analysis of FFAs yielded 2 main principal components. The 1st factor, correlated with all FFAs excepting eicosatrienoic acid, allowed discrimination between curing times. The 2nd factor, correlated with eicosatrienoic acid, permitted discrimination between breeds. © 2013 Institute of Food Technologists®

Near-ultraviolet radiation-induced lipid peroxidation and membrane effects in Escherichia coli and human skin fibroblasts

International Nuclear Information System (INIS)

Chamberlain, J.

1987-01-01

The first part of this thesis examines the response of an unsaturated fatty acid auxotroph, Escherichia coli K1060 to broad-band near-UV radiation. Sensitivity, lipid peroxidation and leakage of rubidium from irradiated cells were found to increase with increasing unsaturation of membrane fatty acids. The involvement of singlet oxygen was implicated by an increase in sensitivity, lipid peroxidation and leakage of rubidium following irradiation in deuterium oxide. Some factors influencing survival following irradiation were investigated, where lower growth rates were shown to enhance survival. In the second part, the study was extended to human fibroblasts where a normal human skin fibroblast strain, GM730 and a strain derived from an actinic reticuloid patient, AR6LO, are compared. Lipid peroxidation was measured in both cell lines following broad-band near-UV irradiation. Membrane activity, as assessed by the pinocytic uptake of 14 C-sucrose and its subsequent release from the cell, was measured. Near-UV irradiation was found to increase such activity in both strains. Vitamin E and Trolox-C were found to decrease this response in AR6LO but not GM730 cells. The final part consists of preliminary investigations into the near-UV induced peroxidation of fatty acids and liposomes, and the subsequent increase in the level of hydroperoxides in the hours following irradiation. (author)

Electroreduction of peroxycitric acid coexisting with hydrogen peroxide in aqueous solution

International Nuclear Information System (INIS)

Ferdousi, Begum Nadira; Islam, Md. Mominul; Okajima, Takeyoshi; Ohsaka, Takeo

2007-01-01

The electrochemical reduction of peroxycitric acid (PCA) coexisting with citric acid and hydrogen peroxide (H 2 O 2 ) in the equilibrium mixture was extensively studied at a gold electrode in acetate buffer solutions containing 0.1 M Na 2 SO 4 (pH 2.0-6.0) using cyclic and hydrodynamic voltammetric, and hydrodynamic chronocoulometric measurements. The reduction of PCA was characterized to be an irreversible, diffusion-controlled process, and the cyclic voltammetric reduction peak potential (E p c ) was found to be more positive by ca. 1.0 V than that of the coexisting H 2 O 2 , e.g., the E p c values obtained at 0.1 V s -1 for PCA and H 2 O 2 were 0.35 and -0.35 V, respectively, vs. Ag|AgCl|KCl (sat.) at pH 3.3. The E p c of PCA was found to depend on pH, i.e., at pH > 4.5, the plot of E p c vs. pH gave the slope (-64 mV decade -1 ) which is close to the theoretical value (-59 mV decade -1 ) for an electrode process involving the equal number of electron and proton in the rate-determining step, while at pH p c was almost independent of pH. The relevant electrochemical parameters, Tafel slope, number of electrons, formal potential (E 0 '), cathodic transfer coefficient and standard heterogeneous rate constant (k 0 ') for the reduction of PCA and the diffusion coefficient of PCA were determined to be ca. 100 mV decade -1 , 2, 1.53 V (at pH 2.6), 0.29, 1.2 x 10 -12 cm s -1 and 0.29 x 10 -5 cm 2 s -1 , respectively, and except for E 0 ', the obtained values were almost independent of the solution pH. The overall mechanism of the reduction of PCA was discussed

Photochemistry of peroxoborates: borate inhibition of the photodecomposition of hydrogen peroxide.

Science.gov (United States)

Rey, Sébastien; Davies, D Martin

2006-12-13

The UV absorbance and photochemical decomposition kinetics of hydrogen peroxide in borate/boric acid buffers were investigated as a function of pH, total peroxide concentration, and total boron concentration. At higher pH borate/boric acid inhibits the photodecomposition of hydrogen peroxide (molar absorptivity and quantum yield of H(2)O(2) and HO(2) (-), (19.0+/-0.3) M(-1) cm(-1) and 1, and (237+/-7) M(-1) cm(-1) and 0.8+/-0.1, respectively). The results are consistent with the equilibrium formation of the anions monoperoxoborate, K(BOOH)=[H(+)][HOOB(OH)(3) (-)]/([B(OH)(3)][H(2)O(2)]), 2.0 x 10(-8), R. Pizer, C. Tihal, Inorg. Chem. 1987, 26, 3639-3642, and monoperoxodiborate, K(BOOB)=[BOOB(2-)]/([B(OH)(4) (-)][HOOB(OH)(3) (-)]), 1.0+/-0.3 or 4.3+/-0.9, depending upon the conditions, with molar absorptivity, (19+/-1) M(-1) cm(-1) and (86+/-15) M(-1) cm(-1), respectively, and respective quantum yields, 1.1+/-0.1 and 0.04+/-0.04. The low quantum yield of monoperoxodiborate is discussed in terms of the slower diffusion apart of incipient (.)OB(OH)(3) (-) radicals than may be possible for (.)OH radicals, or a possible oxygen-bridged cyclic structure of the monoperoxodiborate.

Safe handling of potential peroxide forming compounds and their corresponding peroxide yielded derivatives.

Energy Technology Data Exchange (ETDEWEB)

Sears, Jeremiah Matthew; Boyle, Timothy J.; Dean, Christopher J.

2013-06-01

This report addresses recent developments concerning the identification and handling of potential peroxide forming (PPF) and peroxide yielded derivative (PYD) chemicals. PPF chemicals are described in terms of labeling, shelf lives, and safe handling requirements as required at SNL. The general peroxide chemistry concerning formation, prevention, and identification is cursorily presented to give some perspective to the generation of peroxides. The procedure for determining peroxide concentrations and the proper disposal methods established by the Hazardous Waste Handling Facility are also provided. Techniques such as neutralization and dilution are provided for the safe handling of any PYD chemicals to allow for safe handling. The appendices are a collection of all available SNL documentation pertaining to PPF/PYD chemicals to serve as a single reference.

Intensity of lipid oxidation and formation of cholesterol oxidation products during frozen storage of raw and cooked chicken

OpenAIRE

Conchillo, A. (Ana); Ansorena, D. (Diana); Astiasarán, I. (Iciar)

2004-01-01

Raw and cooked chicken breasts were stored at −18 °C for 3 months under aerobic and vacuum conditions, and the intensity of lipid oxidation and the formation of COP (cholesterol oxidation products) were studied. Raw samples showed low COP levels (4.60–7.40 µg g−1 fat), TBARS (thiobarbituric acid reactive substances) levels (0.01–0.03 mg kg−1) and peroxide values (not detected) under both aerobic and vacuum conditions. Cooked samples (grilled and roasted) showed TBARS levels of 0.36–0.99 mg kg...

A Modified Fluorimetric Method for Determination of Hydrogen Peroxide Using Homovanillic Acid Oxidation Principle

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Biswaranjan Paital

2014-01-01

Full Text Available Hydrogen peroxide (H2O2 level in biological samples is used as an important index in various studies. Quantification of H2O2 level in tissue fractions in presence of H2O2 metabolizing enzymes may always provide an incorrect result. A modification is proposed for the spectrofluorimetric determination of H2O2 in homovanillic acid (HVA oxidation method. The modification was included to precipitate biological samples with cold trichloroacetic acid (TCA, 5% w/v followed by its neutralization with K2HPO4 before the fluorimetric estimation of H2O2 is performed. TCA was used to precipitate the protein portions contained in the tissue fractions. After employing the above modification, it was observed that H2O2 content in tissue samples was ≥2 fold higher than the content observed in unmodified method. Minimum 2 h incubation of samples in reaction mixture was required for completion of the reaction. The stability of the HVA dimer as reaction product was found to be >12 h. The method was validated by using known concentrations of H2O2 and catalase enzyme that quenches H2O2 as substrate. This method can be used efficiently to determine more accurate tissue H2O2 level without using internal standard and multiple samples can be processed at a time with additional low cost reagents such as TCA and K2HPO4.

Protective Effects of Tormentic Acid, a Major Component of Suspension Cultures of Eriobotrya japonica Cells, on Acetaminophen-Induced Hepatotoxicity in Mice

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Wen-Ping Jiang

2017-05-01

Full Text Available An acetaminophen (APAP overdose can cause hepatotoxicity and lead to fatal liver damage. The hepatoprotective effects of tormentic acid (TA on acetaminophen (APAP-induced liver damage were investigated in mice. TA was intraperitoneally (i.p. administered for six days prior to APAP administration. Pretreatment with TA prevented the elevation of serum aspartate aminotransferase (AST, alanine aminotransferase (ALT, total bilirubin (T-Bil, total cholesterol (TC, triacylglycerol (TG, and liver lipid peroxide levels in APAP-treated mice and markedly reduced APAP-induced histological alterations in liver tissues. Additionally, TA attenuated the APAP-induced production of nitric oxide (NO, reactive oxygen species (ROS, tumor necrosis factor-alpha (TNF-α, interleukin-1beta (IL-1β, and IL-6. Furthermore, the Western blot analysis showed that TA blocked the protein expression of inducible NO synthase (iNOS and cyclooxygenase-2 (COX-2, as well as the inhibition of nuclear factor-kappa B (NF-κB and mitogen-activated protein kinases (MAPKs activation in APAP-injured liver tissues. TA also retained the superoxidase dismutase (SOD, glutathione peroxidase (GPx, and catalase (CAT in the liver. These results suggest that the hepatoprotective effects of TA may be related to its anti-inflammatory effect by decreasing thiobarbituric acid reactive substances (TBARS, iNOS, COX-2, TNF-α, IL-1β, and IL-6, and inhibiting NF-κB and MAPK activation. Antioxidative properties were also observed, as shown by heme oxygenase-1 (HO-1 induction in the liver, and decreases in lipid peroxides and ROS. Therefore, TA may be a potential therapeutic candidate for the prevention of APAP-induced liver injury by inhibiting oxidative stress and inflammation.

Effect of Piper betle leaf extract on alcoholic toxicity in the rat brain.

Science.gov (United States)

Saravanan, R; Rajendra Prasad, N; Pugalendi, K V

2003-01-01

The protective effect of Piper betle, a commonly used masticatory, has been examined in the brain of ethanol-administered Wistar rats. Brain of ethanol-treated rats exhibited increased levels of lipids, lipid peroxidation, and disturbances in antioxidant defense. Subsequent to the experimental induction of toxicity (i.e., the initial period of 30 days), aqueous P. betle extract was simultaneously administered in three different doses (100, 200, and 300 mg kg(-1)) for 30 days along with the daily dose of alcohol. P. betle coadministration resulted in significant reduction of lipid levels (free fatty acids, cholesterol, and phospholipids) and lipid peroxidation markers such as thiobarbituric acid reactive substances and hydroperoxides. Further, antioxidants, like reduced glutathione, vitamin C, vitamin E, superoxide dismutase, catalase, and glutathione peroxidase, were increased in P. betle-coadministered rats. The higher dose of extract (300 mg kg(-1)) was more effective, and these results indicate the neuroprotective effect of P. betle in ethanol-treated rats.

Different modes of hydrogen peroxide action during seed germination

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Łukasz eWojtyla

2016-02-01

Full Text Available Hydrogen peroxide was initially recognized as a toxic molecule that causes damage at different levels of cell organization and thus losses in cell viability. From the 1990s, the role of hydrogen peroxide as a signaling molecule in plants has also been discussed. The beneficial role of H2O2 as a central hub integrating signaling network in response to biotic and abiotic stress and during developmental processes is now well established. Seed germination is the most pivotal phase of the plant life cycle, affecting plant growth and productivity. The function of hydrogen peroxide in seed germination and seed aging has been illustrated in numerous studies; however, the exact role of this molecule remains unknown. This review evaluates evidence that shows that H2O2 functions as a signaling molecule in seed physiology in accordance with the known biology and biochemistry of H2O2. The importance of crosstalk between hydrogen peroxide and a number of signaling molecules, including plant phytohormones such as abscisic acid, gibberellins and ethylene and reactive molecules such as nitric oxide and hydrogen sulfide acting on cell communication and signaling during seed germination, is highlighted. The current study also focuses on the detrimental effects of H2O2 on seed biology, i.e., seed aging that leads to a loss of germination efficiency. The dual nature of hydrogen peroxide as a toxic molecule on one hand and as a signal molecule on the other is made possible through the precise spatial and temporal control of its production and degradation. Levels of hydrogen peroxide in germinating seeds and young seedlings can be modulated via pre-sowing seed priming/conditioning. This rather simple method is shown to be a valuable tool for improving seed quality and for enhancing seed stress tolerance during post-priming germination. In this review, we outline how seed priming/conditioning affects the integrative role of hydrogen peroxide in seed germination and

In vitro free radical scavenging activity of platinum nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Watanabe, Aki; Kajita, Masashi; Kim, Juewon; Kanayama, Atsuhiro; Miyamoto, Yusei [Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Bioscience Building 402, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562 (Japan); Takahashi, Kyoko; Mashino, Tadahiko, E-mail: yusei74@k.u-tokyo.ac.j [Department of Pharmaceutical Sciences, Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato, Tokyo 105-8512 (Japan)

2009-11-11

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 AOO. generated from 2,2-azobis (2-aminopropane) dihydrochloride (AAPH) by thermal decomposition in the presence of O{sub 2} 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 AOO. 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 {mu}M DPPH radical for 5 min. Even when twice diluted in half, the PAA-Pt still quenched 100% of the 250 {mu}M DPPH radical. The scavenging activity of PAA-Pt is durable. These observations suggest that PAA-Pt is an efficient scavenger of free radicals.

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

Directory of Open Access Journals (Sweden)

Atena Shirzad

2014-03-01

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

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

Science.gov (United States)

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

2014-01-01

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

21 CFR 172.802 - Acetone peroxides.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acetone peroxides. 172.802 Section 172.802 Food and... Multipurpose Additives § 172.802 Acetone peroxides. The food additive acetone peroxides may be safely used in... acetone peroxide, with minor proportions of higher polymers, manufactured by reaction of hydrogen peroxide...

Effect of antioxidants on thiobarbituric acid reactive substances, psychrotrophic bacteria and functional properties of mechanically deboned chicken meat irradiated with Cobalto-60 and electron beam sources

Energy Technology Data Exchange (ETDEWEB)

Brito, Poliana de Paula; Azevedo, Heliana de; Roque, Claudio Vitor; Pomarico Neto, Walter, E-mail: hgomes@cnen.gov.br, E-mail: pbrito@cnen.gov.br, E-mail: cvroque@cnen.gov.br, E-mail: abrusqui@cnen.gov.br [Comissao Nacional de Energia Nuclear (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas; Mourao, Gerson Barreto; Orlando, Eduardo Adilson; Miyagusku, Luciana, E-mail: marciamh@ital.sp.gov.br, E-mail: eduardo.orlando@ital.sp.gov.br [Instituto de Tecnologia dos Alimentos (ITAL), Campinas, SP (Brazil)

2013-07-01

Samples of MDCM with skin were divided into three groups: control (without antioxidants), Antioxidant 1 (Sodium Polyphosphate and Sodium Ascorbate and Antioxidant 2 (Rosemary Extract and α-Tocopherol. The three batches of samples were divided into nine groups: no antioxidant and non-irradiated (C), with antioxidant A1 and non-irradiated (A1), with antioxidant A2 and non-irradiated (A2) without antioxidant and irradiated in Cobalt-60 source (Co), with antioxidant A1 irradiated in Cobalt 60 source (A1Co) with antioxidant A2 irradiated in Cobalt-60 source (A2Co) with antioxidant A1 irradiated in Electron beam (A1Eb) and with antioxidant A2 irradiated in Electron beam (A2Eb). The samples was conditioned in a transparent, low density frozen overnight at a temperature of -18 ± 1 deg C in a chamber, and irradiated in this state with a dose of 3.0 kGy, used two sources of radiation: Cobalt-60 (3.1 kGy/h) and electron beam (7.86 kGy/s). After this process, the samples were evaluated during the refrigeration period (2 ± 1 deg C) for 11 days for the following analysis: total psychrotrophic bacteria count and thiobarbituric acid reactive substances (TBARS) and the analysis of functional properties were performed after the irradiation process. The use of the combination of rosemary antioxidant and α-tocopherol were able to significantly decrease TBARS values caused by the irradiation of samples in MDCM cobalt-60 sources and electron beam, and show a synergetic effect to processing with ionizing radiation to reduce of psychrotrophic bacteria count. The use of irradiation processing of MDCM did not negatively affect the functional properties studied. (author)

Effect of antioxidants on thiobarbituric acid reactive substances, psychrotrophic bacteria and functional properties of mechanically deboned chicken meat irradiated with Cobalto-60 and electron beam sources

International Nuclear Information System (INIS)

Brito, Poliana de Paula; Azevedo, Heliana de; Roque, Claudio Vitor; Pomarico Neto, Walter

2013-01-01

Samples of MDCM with skin were divided into three groups: control (without antioxidants), Antioxidant 1 (Sodium Polyphosphate and Sodium Ascorbate and Antioxidant 2 (Rosemary Extract and α-Tocopherol. The three batches of samples were divided into nine groups: no antioxidant and non-irradiated (C), with antioxidant A1 and non-irradiated (A1), with antioxidant A2 and non-irradiated (A2) without antioxidant and irradiated in Cobalt-60 source (Co), with antioxidant A1 irradiated in Cobalt 60 source (A1Co) with antioxidant A2 irradiated in Cobalt-60 source (A2Co) with antioxidant A1 irradiated in Electron beam (A1Eb) and with antioxidant A2 irradiated in Electron beam (A2Eb). The samples was conditioned in a transparent, low density frozen overnight at a temperature of -18 ± 1 deg C in a chamber, and irradiated in this state with a dose of 3.0 kGy, used two sources of radiation: Cobalt-60 (3.1 kGy/h) and electron beam (7.86 kGy/s). After this process, the samples were evaluated during the refrigeration period (2 ± 1 deg C) for 11 days for the following analysis: total psychrotrophic bacteria count and thiobarbituric acid reactive substances (TBARS) and the analysis of functional properties were performed after the irradiation process. The use of the combination of rosemary antioxidant and α-tocopherol were able to significantly decrease TBARS values caused by the irradiation of samples in MDCM cobalt-60 sources and electron beam, and show a synergetic effect to processing with ionizing radiation to reduce of psychrotrophic bacteria count. The use of irradiation processing of MDCM did not negatively affect the functional properties studied. (author)

Organo-bridged silsesquioxane titanates for heterogeneous catalytic epoxidation with aqueous hydrogen peroxide

NARCIS (Netherlands)

Wang, Y.M.; Magusin, P.C.M.M.; Santen, van R.A.; Abbenhuis, H.C.L.

2007-01-01

Organo-bridged silsesquioxane titanates for heterogeneous catalytic epoxidation with aqueous hydrogen peroxide were synthesized through the acid-catalyzed hydrolysis and co-condensation of organotrialkoxysilane monomers and a,¿-bis(trialkoxysilyl) alkane cross-linkers in ethanol–water solution, with

Hydrogen peroxide kinetics in water radiolysis

Science.gov (United States)

Iwamatsu, Kazuhiro; Sundin, Sara; LaVerne, Jay A.

2018-04-01

The kinetics of the formation and reaction of hydrogen peroxide in the long time γ- radiolysis of water is examined using a combination of experiment with model calculations. Escape yields of hydrogen peroxide on the microsecond time scale are easily measured with added radical scavengers even with substantial amounts of initial added hydrogen peroxide. The γ-radiolysis of aqueous hydrogen peroxide solutions without added radical scavengers reach a steady state limiting concentration of hydrogen peroxide with increasing dose, and that limit is directly proportional to the initial concentration of added hydrogen peroxide. The dose necessary to reach that limiting hydrogen peroxide concentration is also proportional to the initial concentration, but dose rate has a very small effect. The addition of molecular hydrogen to aqueous solutions of hydrogen peroxide leads to a decrease in the high dose limiting hydrogen peroxide concentration that is linear with the initial hydrogen concentration, but the amount of decrease is not stoichiometric. Proton irradiations of solutions with added hydrogen peroxide and hydrogen are more difficult to predict because of the decreased yields of radicals; however, with a substantial increase in dose rate there is a sufficient decrease in radical yields that hydrogen addition has little effect on hydrogen peroxide decay.

Erythrocyte osmotic fragility and lipid peroxidation following chronic co-exposure of rats to chlorpyrifos and deltamethrin, and the beneficial effect of alpha-lipoic acid

Directory of Open Access Journals (Sweden)

Chidiebere Uchendu

2014-01-01

Full Text Available The present study aimed to evaluate the effect of chronic co-exposure to chlorpyrifos (CPF and deltamethrin (DLT on erythrocyte osmotic fragility, lipid peroxidation and the ameliorative effect of alpha-lipoic acid (ALA on erythrocyte fragility. Thirty-six male Wistar rats divided into six groups of six rats each were used for the study. Groups I (S/oil and II (ALA were given soya oil (2 ml/kg and ALA (60 mg/kg, respectively. Rats in group III (DLT and IV (CPF were exposed to DLT (6.25 mg/kg and CPF (4.75 mg/kg (1/20th of the previously determined LD50 of 125 mg/kg and 95 mg/kg, respectively, over a period of 48 h. Rats in group V (CPF + DLT were co-exposed to CPF (4.75 mg/kg and DLT (6.25 mg/kg, while those in group VI (ALA + CPF + DLT were pretreated with ALA (60 mg/kg and then co-exposed to CPF and DLT, 45 min later. The treatments were administered by gavage once daily for a period of 16 weeks. Blood collected at the end of the experimental period were analyzed for erythrocyte osmotic fragility and malondialdehyde (MDA concentration. The study showed that chronic co-exposure to CPF and DLT resulted in an increase in erythrocyte fragility and MDA concentration which were ameliorated by supplementation with alpha-lipoic acid. The study concluded that repeated co-exposure to CPF and DLT elevated erythrocyte fragility probably due to increased lipid peroxidation, and pretreatment with alpha-lipoic acid ameliorated these alterations.

Lipid profiling following intake of the omega 3 fatty acid DHA identifies the peroxidized metabolites F4-neuroprostanes as the best predictors of atherosclerosis prevention.

Science.gov (United States)

Gladine, Cécile; Newman, John W; Durand, Thierry; Pedersen, Theresa L; Galano, Jean-Marie; Demougeot, Céline; Berdeaux, Olivier; Pujos-Guillot, Estelle; Mazur, Andrzej; Comte, Blandine

2014-01-01

The anti-atherogenic effects of omega 3 fatty acids, namely eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) are well recognized but the impact of dietary intake on bioactive lipid mediator profiles remains unclear. Such a profiling effort may offer novel targets for future studies into the mechanism of action of omega 3 fatty acids. The present study aimed to determine the impact of DHA supplementation on the profiles of polyunsaturated fatty acids (PUFA) oxygenated metabolites and to investigate their contribution to atherosclerosis prevention. A special emphasis was given to the non-enzymatic metabolites knowing the high susceptibility of DHA to free radical-mediated peroxidation and the increased oxidative stress associated with plaque formation. Atherosclerosis prone mice (LDLR(-/-)) received increasing doses of DHA (0, 0.1, 1 or 2% of energy) during 20 weeks leading to a dose-dependent reduction of atherosclerosis (R(2) = 0.97, p = 0.02), triglyceridemia (R(2) = 0.97, p = 0.01) and cholesterolemia (R(2) = 0.96, pF4-neuroprostanes, a specific class of DHA peroxidized metabolites, was strongly correlated with the hepatic DHA level. Moreover, unbiased statistical analysis including correlation analyses, hierarchical cluster and projection to latent structure discriminate analysis revealed that the hepatic level of F4-neuroprostanes was the variable most negatively correlated with the plaque extent (pF4-neuroprostanes in particular, are potential biomarkers of DHA-associated atherosclerosis prevention. While these may contribute to the anti-atherogenic effects of DHA, further in vitro investigations are needed to confirm such a contention and to decipher the molecular mechanisms of action.

Reactive oxygen species and lipid peroxidation product-scavenging ability of yogurt organisms.

Science.gov (United States)

Lin, M Y; Yen, C L

1999-08-01

The antioxidative activity of the intracellular extracts of yogurt organisms was investigated. All 11 strains tested, including five strains of Streptococcus thermophilus and six strains of Lactobacillus delbrueckii ssp. bulgaricus, demonstrated an antioxidative effect on the inhibition of linoleic acid peroxidation. The antioxidative effect of intracellular extracts of 10(8) cells of yogurt organisms was equivalent to 25 to 96 ppm butylated hydroxytoluene, which indicated that all strains demonstrated excellent antioxidative activity. The scavenging of reactive oxygen species, hydroxyl radical, and hydrogen peroxide was studied for intracellular extracts of yogurt organisms. All strains showed reactive oxygen species-scavenging ability. Lactobacillus delbrueckii ssp. bulgaricus Lb demonstrated the highest hydroxyl radical-scavenging ability at 234 microM. Streptococcus thermophilus MC and 821 and L. delbrueckii ssp. bulgaricus 448 and 449 scavenged the most hydrogen peroxide at approximately 50 microM. The scavenging ability of lipid peroxidation products, t-butylhydroperoxide and malondialdehyde, was also evaluated. Results showed that the extracts were not able to scavenge the t-butylhydroperoxide. Nevertheless, malondialdehyde was scavenged well by most strains.

Effect of Acetyl-L-Carnitine on Antioxidant Status, Lipid Peroxidation, and Oxidative Damage of Arsenic in Rat.

Science.gov (United States)

Sepand, Mohammad Reza; Razavi-Azarkhiavi, Kamal; Omidi, Ameneh; Zirak, Mohammad Reza; Sabzevari, Samin; Kazemi, Ali Reza; Sabzevari, Omid

2016-05-01

Arsenic (As) is a widespread environmental contaminant present around the world in both organic and inorganic forms. Oxidative stress is postulated as the main mechanism for As-induced toxicity. This study was planned to examine the protective effect of acetyl-L-carnitine (ALC) on As-induced oxidative damage in male rats. Animals were randomly divided into four groups of control (saline), sodium arsenite (NaAsO2, 20 mg/kg), ALC (300 mg/kg), and NaAsO2 plus ALC. Animals were dosed orally for 28 successive days. Blood and tissue samples including kidney, brain, liver, heart, and lung were collected on the 28th day and evaluated for oxidative damage and histological changes. NaAsO2 exposure caused a significant lipid peroxidation as evidenced by elevation in thiobarbituric acid-reactive substances (TBARS). The activity of antioxidant enzymes such as glutathione-S-transferase (GST), catalase (CAT), superoxide dismutase (SOD), as well as sulfhydryl group content (SH group) was significantly suppressed in various organs following NaAsO2 treatment (P < 0.05). Furthermore, NaAsO2 administration increased serum values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and bilirubin. Our findings revealed that co-administration of ALC and NaAsO2 significantly suppressed the oxidative damage induced by NaAsO2. Tissue histological studies have confirmed the biochemical findings and provided evidence for the beneficial role of ALC. The results concluded that ALC attenuated NaAsO2-induced toxicity, and this protective effect may result from the ability of ALC in maintaining oxidant-antioxidant balance.

Effect of Time Lenght Fermentation to Katsuobushi Oxidation Rate As Fish Flavor Based

Science.gov (United States)

Amalia, U.; Rianingsih, L.; Wijayanti, I.

2018-02-01

Katsuobushi or dried smoked skipjack had a distinctive flavor and widely used in traditional Japanese cuisine. This study aimed to evaluate the oxidation rate of Katsuobushi with different lenght fermentation. The processing treatment of the product were the differences of fish boiling time (30 min and 60 min) and the lenght of fermentation: 1 week, 2 weeks and 3 weeks. The glutamic acid content, the oxidation rate (thiobarbituric acid and peroxide value) and Total Plate Count of katsuobushi were analyzed statistically using analysis of varians. Significant differences were found among 3 weeks of fermentation compare to 1 weeks fermentation (P fermentation was potential to be developed become basic ingredients for the fish flavor.

Photocatalytic transformation of dyes and by-products in the presence of hydrogen peroxide.

Science.gov (United States)

Subba Rao, K V; Subrahmanyam, M; Boule, P

2003-08-01

The efficiency of the photocatalytic degradation of dyes and dyeing industry pollutants on immobilized photocatalysts can be improved by addition of hydrogen peroxide, due to its photocatalytic decomposition on TiO2. Experiments were carried out with two azodyes, Acid Orange-7 (AO-7) and Tartrazine (Tart), with 3-nitrobenzenesulfonic add (3-NBSA) which is a chemical intermediate in the dye industry and with real industrial wastewaters, using a thin-film fixed bed reactor. The effect of hydrogen peroxide is only significant for concentrations higher than 5 x 10(-3) M (170 mg l(-1)).

Impacts of heterogeneous reactions to atmospheric peroxides: Observations and budget analysis study

Science.gov (United States)

Qin, Mengru; Chen, Zhongming; Shen, Hengqing; Li, Huan; Wu, Huihui; Wang, Yin

2018-06-01

Atmospheric peroxides play important roles in atmospheric chemistry, acting as reactive oxidants and reservoirs of HOX and ROX radicals. Field measurements of atmospheric peroxides were conducted over urban Beijing from 2015 to 2016, including dust storm days, haze days and different seasons. We employed a box model based on RACM2 mechanism to conduct concentration simulation and budget analysis of hydrogen peroxide (H2O2) and peroxyacetic acid (PAA). In this study, heterogeneous reaction is found to be a significant sink for atmospheric H2O2 and PAA in urban Beijing. Here, we recommend a suitable uptake coefficient formula considering the water effect for model research of peroxides. It is found that H2O2 and PAA unexpectedly maintained considerable concentrations on haze days, even higher than that on non-haze days. This phenomenon is mainly ascribed to relatively high levels of volatile organic compounds and ozone on haze days. In addition, high levels of water vapor in pollution episode can promote not only the heterogeneous uptake to aerosol phase but also the production of H2O2. Atmospheric PAA formation is suggested to be sensitive to alkenes and NOX in urban Beijing. In particular, with the help of peroxides, sulfate formation rate from heterogeneous uptake could increase by ∼4 times on haze days, indicating the potential effect of peroxides on enhancement of aerosol oxidative property and secondary sulfate formation.

Effect of Naringenin (A naturally occurring flavanone) Against Pilocarpine-induced Status Epilepticus and Oxidative Stress in Mice

Science.gov (United States)

Shakeel, Sheeba; Rehman, Muneeb U.; Tabassum, Nahida; Amin, Umar; Mir, Manzoor ur Rahman

2017-01-01

reduced lipid peroxidation. Abbreviations used: 6-OHDA: 6-hydroxydopamine, AED: Anti epileptic drugs, AIDS: Acquired immune deficiency syndrome, ANOVA: Analysis of variance, ATP: Adenosine triphosphate, CA: Cornu ammonis, CAT: Catalase, DG: Dentate gyrus, EDTA: Ethylenediamine tetra acetic acid, GR: Glutathione reductase, GSH: Glutathione reduced, HCl: Hydrochloric acid, IL-1β: Interleukin 1 beta, LPO: Lipid peroxidation, MDA: Malondialdehyde, NADPH: Nicotinamide adenine dinucleotide phosphate, PMS: post mitochondrial supernatant, SE: Status epilepticus, SEM: Standard error of the mean, SOD Superoxide dismutase, TBA: Thiobarbituric acid, TBARS: Thiobarbituric acid reactive substance, TLE: Temporal lobe epilepsy, TNF-α: Tumor necrosis factor alpha PMID:28479741

Potential for free radical-induced lipid peroxidation as a cause of endothelial cell injury in Rocky Mountain spotted fever.

Science.gov (United States)

Silverman, D J; Santucci, L A

1988-01-01

Cells infected by Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever, display unusual intracellular morphological changes characterized by dilatation of the membranes of the endoplasmic reticulum and outer nuclear envelope. These changes are consistent with those that might be expected to occur following peroxidation of membrane lipids initiated by oxygen radical species, such as the hydroxyl radical or a variety of organic radicals. Using a fluorescent probe, we have found significantly increased levels of peroxides in human endothelial cells infected by R. rickettsii. Studies with desferrioxamine, an iron chelator effective in preventing formation of the hydroxyl radical from hydrogen peroxide and the superoxide free radical, reduced peroxide levels in infected cells to those found in uninfected cells. This observation suggests that the increased peroxides in infected cells may be lipid peroxides, degradation products of free radical attack on polyenoic fatty acids. The potential for lipid peroxidation as an important mechanism in endothelial cell injury caused by R. rickettsii is discussed. Images PMID:3141280

Studies on lipid peroxidation and anti-LPO chemicals

International Nuclear Information System (INIS)

Wang Chongdao; Qiang Yizhong; Lao Qinhua

1995-02-01

The contents of lipid peroxides (LPO) in sera and tissues were determined by the modified spectrophotometry of TBA, and the effects of three chemicals on lipid peroxidation induced by radiation were observed. The items studied included: (1) the normal values of LPO of sera in rats and adults: (2) the normal values in some tissues of rats; (3) the changes of LPO levels of sera in patients with some mental diseases and patients with malignant tumours before and after local gamma irradiation exposure; (4) the changes of LPO contents of some tissues in rats after whole-body gamma irradiation exposure; (5) the changes of LPO contents of some tissues in mice after internal exposure by Th(NO 3 ) 4 solution; (6) the effects of chinonin, tannic acid and squalene on lipid peroxidation induced by irradiation. The results were as follows: (1) the LPO contents in patients with some mental diseases dramatically increased; (2) there was marked difference between the LPO levels before and after local gamma irradiation exposure in patients with malignant tumours; (3) the LPO contents in some tissues of rats remarkably increased after whole-body gamma irradiation exposure; (4) the LPO contents in some tissues of mice dramatically increased and their protein contents markedly reduced after internal exposure, showing a negative correlation between them; (5) a gradual increase in LPO contents in some tissues of mice appeared with increasing dosage of whole-body gamma irradiation exposure at dose range from 0 to 4 Gy. A linear relationship between the dose and the LPO contents was observed; (6) all three chemicals could reduce the LPO levels in liver, spleen and kidney of the irradiated mice. The efficacy of chinonin was better than that of tannic acid and squalene. (5 tabs., 1 fig.)

Reaction Mechanisms and Structural and Physicochemical Properties of Caffeic Acid Grafted Chitosan Synthesized in Ascorbic Acid and Hydroxyl Peroxide Redox System.

Science.gov (United States)

Liu, Jun; Pu, Huimin; Chen, Chong; Liu, Yunpeng; Bai, Ruyu; Kan, Juan; Jin, Changhai

2018-01-10

The ascorbic acid (AA) and hydroxyl peroxide (H 2 O 2 ) redox pair induced free radical grafting reaction is a promising approach to conjugate phenolic groups with chitosan (CS). In order to reveal the exact mechanisms of the AA/H 2 O 2 redox pair induced grafting reaction, free radicals generated in the AA/H 2 O 2 redox system were compared with hydroxyl radical ( • OH) produced in the Fe 2+ /H 2 O 2 redox system. Moreover, the structural and physicochemical properties of caffeic acid grafted CS (CA-g-CS) synthesized in these two redox systems were compared. Results showed that only ascorbate radical (Asc •- ) was produced in the AA/H 2 O 2 system. The reaction between Asc •- and CS produced novel carbon-centered radicals, whereas no new free radicals were detected when • OH reacted with CS. Thin layer chromatography, UV-vis, Fourier transform infrared, and nuclear magnetic resonance spectroscopic analyses all confirmed that CA was successfully grafted onto CS through Asc •- . However, CA could be hardly grafted onto CS via • OH. CA-g-CS synthesized through Asc •- exhibited lower thermal stability and crystallinity than the reaction product obtained through • OH. For the first time, our results demonstrated that the synthesis of CA-g-CS in the AA/H 2 O 2 redox system was mediated by Asc •- rather than • OH.

Novel free-radical mediated lipid peroxidation biomarkers in newborn plasma.

Science.gov (United States)

Sánchez-Illana, Ángel; Thayyil, Sudhin; Montaldo, Paolo; Jenkins, Dorothea; Quintás, Guillermo; Oger, Camille; Galano, Jean-Marie; Vigor, Claire; Durand, Thierry; Vento, Máximo; Kuligowski, Julia

2017-12-15

Oxidative stress derived from perinatal asphyxia appears to be closely linked to neonatal brain damage and lipid peroxidation biomarkers have shown to provide predictive power of oxidative stress related pathologies in situations of hypoxia and reoxygenation in the newborn. The objective of this work was to develop and validate of a comprehensive liquid chromatography tandem mass spectrometry approach for the quantitative profiling of 28 isoprostanoids in newborn plasma samples covering a broad range of lipid peroxidation product classes. The method was developed taking into account the specific requirements for its use in neonatology (i.e. limited sample volumes, straightforward sample processing and high analytical throughput). The method was validated following stringent FDA guidelines and was then applied to the analysis of 150 plasma samples collected from newborns. Information obtained from the quantitative analysis of isoprostanoids was critically compared to that provided by a previously developed approach aiming at the semi-quantitative detection of total parameters of fatty acid derived lipid peroxidation biomarkers. Copyright © 2017 Elsevier B.V. All rights reserved.

Combination process method of lactic acid hydrolysis and hydrogen peroxide oxidation for cassava starch modification

Science.gov (United States)

Sumardiono, Siswo; Pudjihastuti, Isti; Budiyono, Hartanto, Hansen; Sophiana, Intan Clarissa

2017-05-01

Indonesia is one of the world's largest wheat importer, some research are conducted to find other carbohydrate sources which can replace wheat. Cassava is very easy to find and grown in tropical climates especially Indonesia. The research is focused on cassava starch modification as a substitute for wheat flour in order to reduce consumption of wheat flour. The aim of this research is to assess the effect of temperature, pH, and the concentration of H2O2 in modifying cassava starch which. The combination methods are lactic acid hydroxylation and hydrogen peroxide oxidation to improve baking expansion. The carboxyl group, carbonyl group, swelling power, starch solubility, and baking expansion of starch are analized and calculated. Results showed that the modified cassava starch can substitute wheat flour with optimum conditions process at a concentration of H2O2 is 1.5% w/w, oxidation temperature is 50°C, and pH is 3 by the value of swelling power is 6.82%, solubility is 0.02%, and baking expansion is 7.2 cm3/gram.

Hydrogen peroxide as a sustainable energy carrier: Electrocatalytic production of hydrogen peroxide and the fuel cell

International Nuclear Information System (INIS)

Fukuzumi, Shunichi; Yamada, Yusuke; Karlin, Kenneth D.

2012-01-01

This review describes homogeneous and heterogeneous catalytic reduction of dioxygen with metal complexes focusing on the catalytic two-electron reduction of dioxygen to produce hydrogen peroxide. Whether two-electron reduction of dioxygen to produce hydrogen peroxide or four-electron O 2 -reduction to produce water occurs depends on the types of metals and ligands that are utilized. Those factors controlling the two processes are discussed in terms of metal–oxygen intermediates involved in the catalysis. Metal complexes acting as catalysts for selective two-electron reduction of oxygen can be utilized as metal complex-modified electrodes in the electrocatalytic reduction to produce hydrogen peroxide. Hydrogen peroxide thus produced can be used as a fuel in a hydrogen peroxide fuel cell. A hydrogen peroxide fuel cell can be operated with a one-compartment structure without a membrane, which is certainly more promising for the development of low-cost fuel cells as compared with two compartment hydrogen fuel cells that require membranes. Hydrogen peroxide is regarded as an environmentally benign energy carrier because it can be produced by the electrocatalytic two-electron reduction of O 2 , which is abundant in air, using solar cells; the hydrogen peroxide thus produced could then be readily stored and then used as needed to generate electricity through the use of hydrogen peroxide fuel cells.

Hydrogen Peroxide as a Sustainable Energy Carrier: Electrocatalytic Production of Hydrogen Peroxide and the Fuel Cell.

Science.gov (United States)

Fukuzumi, Shunichi; Yamada, Yusuke; Karlin, Kenneth D

2012-11-01

This review describes homogeneous and heterogeneous catalytic reduction of dioxygen with metal complexes focusing on the catalytic two-electron reduction of dioxygen to produce hydrogen peroxide. Whether two-electron reduction of dioxygen to produce hydrogen peroxide or four-electron O 2 -reduction to produce water occurs depends on the types of metals and ligands that are utilized. Those factors controlling the two processes are discussed in terms of metal-oxygen intermediates involved in the catalysis. Metal complexes acting as catalysts for selective two-electron reduction of oxygen can be utilized as metal complex-modified electrodes in the electrocatalytic reduction to produce hydrogen peroxide. Hydrogen peroxide thus produced can be used as a fuel in a hydrogen peroxide fuel cell. A hydrogen peroxide fuel cell can be operated with a one-compartment structure without a membrane, which is certainly more promising for the development of low-cost fuel cells as compared with two compartment hydrogen fuel cells that require membranes. Hydrogen peroxide is regarded as an environmentally benign energy carrier because it can be produced by the electrocatalytic two-electron reduction of O 2 , which is abundant in air, using solar cells; the hydrogen peroxide thus produced could then be readily stored and then used as needed to generate electricity through the use of hydrogen peroxide fuel cells.

Lipid peroxidation inhibition and antiradical activities of some leaf fractions of Mangifera indica.

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Badmus, Jelili A; Adedosu, Temitope O; Fatoki, John O; Adegbite, Victor A; Adaramoye, Oluwatosin A; Odunola, Oyeronke A

2011-01-01

This study was undertaken to assess in vitro lipid peroxidation inhibitions and anti-radical activities of methanolic, chloroform, ethyl acetate and water fractions of Mangifera indica leaf. Inhibition of Fe(2+)-induced lipid peroxidation (LPO) in egg, brain, and liver homogenates, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl (OH-) radical scavenging activities were evaluated. Total phenol was assessed in all fractions, and the reducing power of methanolic fraction was compared to gallic acid and ascorbic acid. The results showed that Fe2+ induced significant lipid peroxidation (LPO) in all the homogenates. Ethyl acetate fraction showed the highest percentage inhibition of LPO in both egg yolk (68.3%) and brain (66.3%), while the aqueous fraction exerted the highest inhibition in liver homogenate (89.1%) at a concentration of 10 microg/mL. These observed inhibitions of LPO by these fractions were higher than that of ascorbic acid used as a standard. The DPPH radical scavenging ability exhibited by ethyl acetate fraction was found to be the highest with IC50 value of 1.5 microg/mL. The ethyl acetate and methanolic fractions had the highest OH- radical scavenging ability with the same IC50 value of 5 microg/mL. The total phenol content of ethyl acetate fraction was the highest with 0.127 microg/mg gallic acid equivalent (GAE). The reductive potential of methanolic fraction showed a concentration-dependent increase. This study showed that inhibition of LPO and the DPPH and OH- radicals scavenging abilities of Mangifera indica leaf could be related to the presence of phenolic compounds. Therefore, the ethyl acetate fraction of the leaf may be a good source of natural antioxidative agent.

Effect of decaffeination of green and roasted coffees on the in vivo antioxidant activity and prevention of liver injury in rats

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Adriene R. Lima

2013-05-01

Full Text Available Decaffeination and roasting affects the composition of the chlorogenic acids in coffee, which have antioxidant potential. The aim of this study was to evaluate the effects of coffee decaffeination on the in vivo antioxidant activity and the prevention of liver damage. The Wistar rats received intraperitoneal doses of carbon tetrachloride and daily doses of Arabica coffee brews (whole and decaffeinated, both green and roasted by gavage for fifteen days. The activity of liver marker enzymes aspartate aminotransferase, alanine aminotransferase and serum albumin were measured as well as the quantification of the thiobarbituric acid reactive species and the content of liver total lipids. Aspartate aminotransferase and alanine aminotransferase are good indicators of liver damage: the results showed that all studied coffee brews decreased the activity of aspartate aminotransferase and alanine aminotransferase, and liver levels of thiobarbituric acid reactive species and total lipids. The compounds presents in coffee brews are able to decrease the hepatic lipid peroxidation induced by carbon tetrachloride, making a significant hepatoprotective effect, in accordance with the liver function tests. The coffee brews are hepatoprotective regardless of the decaffeination process and our results suggest a better protection against liver damage for the roasted coffee brews compared with green coffee brews.

The relative importance of competing pathways for the formation of high-molecular-weight peroxides in the ozonolysis of organic aerosol particles

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M. Mochida

2006-01-01

Full Text Available High-molecular-weight (HMW organic compounds are an important component of atmospheric particles, although their origins, possibly including in situ formation pathways, remain incompletely understood. This study investigates the formation of HMW organic peroxides through reactions involving stabilized Criegee intermediates (SCI's. The model system is methyl oleate (MO mixed with dioctyl adipate (DOA and myristic acid (MA in submicron aerosol particles, and Criegee intermediates are formed by the ozonolysis of the double bond in methyl oleate. An aerosol flow tube coupled to a quadrupole aerosol mass spectrometer (AMS is employed to determine the relative importance of different HMW organic peroxides following the ozonolysis of different mixing mole fractions of MO in DOA and MA. Possible peroxide products include secondary ozonides (SOZ's, α-acyloxyalkyl hydroperoxides and α-acyloxyalkyl alkyl peroxides (αAAHP-type compounds, diperoxides, and monoperoxide oligomers. Of these, the AMS data identify two SOZ's as major HMW products in the ozonolysis of pure methyl oleate as well as in an inert matrix of DOA to as low as 0.04 mole fraction MO. In comparison, in mixed particles of MO and MA, αAAHP-type compounds form in high yields for MO mole fractions of 0.5 or less, suggesting that SCI's efficiently attack the carboxylic acid group of myristic acid. The reactions of SCI's with carboxylic acid groups to form αAAHP-type compounds therefore compete with those of SCI's with aldehydes to form SOZ's, provided that both types of functionalities are present at significant concentrations. The results therefore suggest that SCI's in atmospheric particles contribute to the transformation of carboxylic acids and other protic groups into HMW organic peroxides.

[Participation of final products of lipid peroxidation in the anticancer mechanism of ionizing radiation and radiomimetic cytostatics].

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Przybyszewski, W M

2001-01-01

This review reports the evidence for the participation of final products of lipid peroxidation in the anticancer mechanism of ionising radiation and radiomimetic cytostatics. Processes of lipid peroxidation occur endogenously in response to oxidative stress and great diversity of reactive metabolites is formed. However, direct observation of radical reaction in pathophysiology of cells, tissues and organs is limited technically. Most investigations focused on the indirect assessment of their final products, aldehydes. The peroxidative breakdown of polyunsaturated fatty acids is believed to be involved in the regulation of cell division, and antitumor effect through biochemical and genetic processes.

EFFECT OF NATURAL IRON OXIDE, HYDROGEN PEROXIDE, AND OXALIC ACID ON PHOTOCHEMICAL DEGRADATION OF 2-CHLOROPHENOL

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W REMACHE

2014-07-01

Full Text Available The voluntary or accidental release of chemical compounds in the environment is a major cause of pollution of natural waters. Most of chlorophenols are toxic and hardly biodegradable and are difficult to remove from the environment. Therefore, it is important to find innovative and economical methods for the safe and complete destruction. The objective of this work is to test the activity photocatalytic of natural iron oxide (NIO in the photodegradation of 2-chlorophenol (2-CP. The analysis chromatographic with HPLC of solutions exposed under UV irradiation revealed that the degradation of 2-CP was negligible under the condition of using only natural iron oxide. The effect of wavelength on photoreactivity of NIO was also investigated in this process: at high wavelength thus at low energy the efficiency of degradation is important. We have also investigated the activation of NIO by hydrogen peroxide and oxalic acid, The results showed that the photodegradation of 2-CP under UVA irradiation could be enhanced greatly in the presence of oxalate. 2-CP was completly removed after 240 minutes of irradiation when the concentration of oxalic acid is equal to 2.10-3 M. The use of 2.0 % of isopropanol as a scavenger confirmed the intervention of hydroxyl radicals in the photodegradation of 2-CP.

Hydrogen peroxide stimulates cell motile activity through LPA receptor-3 in liver epithelial WB-F344 cells

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Shibata, Ayano; Tanabe, Eriko; Inoue, Serina; Kitayoshi, Misaho; Okimoto, Souta; Hirane, Miku; Araki, Mutsumi [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Fukushima, Nobuyuki [Division of Molecular Neurobiology, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Tsujiuchi, Toshifumi, E-mail: ttujiuch@life.kindai.ac.jp [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan)

2013-04-12

Highlights: •Hydrogen peroxide stimulates cell motility of WB-F344 cells. •LPA{sub 3} is induced by hydrogen peroxide in WB-F344 cells. •Cell motility by hydrogen peroxide is inhibited in LPA{sub 3} knockdown cells. •LPA signaling is involved in cell migration by hydrogen peroxide. -- Abstract: Hydrogen peroxide which is one of reactive oxygen species (ROS) mediates a variety of biological responses, including cell proliferation and migration. In the present study, we investigated whether lysophosphatidic acid (LPA) signaling is involved in cell motile activity stimulated by hydrogen peroxide. The rat liver epithelial WB-F344 cells were treated with hydrogen peroxide at 0.1 or 1 μM for 48 h. In cell motility assays, hydrogen peroxide treated cells showed significantly high cell motile activity, compared with untreated cells. To measure the expression levels of LPA receptor genes, quantitative real time RT-PCR analysis was performed. The expressions of LPA receptor-3 (Lpar3) in hydrogen peroxide treated cells were significantly higher than those in control cells, but not Lpar1 and Lpar2 genes. Next, to assess the effect of LPA{sub 3} on cell motile activity, the Lpar3 knockdown cells from WB-F344 cells were also treated with hydrogen peroxide. The cell motile activity of the knockdown cells was not stimulated by hydrogen peroxide. Moreover, in liver cancer cells, hydrogen peroxide significantly activated cell motility of Lpar3-expressing cells, but not Lpar3-unexpressing cells. These results suggest that LPA signaling via LPA{sub 3} may be mainly involved in cell motile activity of WB-F344 cells stimulated by hydrogen peroxide.

Effect of ultrasonic pre-treatment of thermomechanical pulp on hydrogen peroxide bleaching

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Loranger, E.; Charles, A.; Daneault, C.

2012-12-01

Ultrasound pre-treatments of softwood TMP had been carried to evaluate its impact on the efficiency of hydrogen peroxide bleaching. The trials were performed after a factorial design of experiment using frequency, power and time as variables. The experiments were conducted in an ultrasonic bath and then bleached with hydrogen peroxide. Measurements such as brightness, L*A*B* color system coordinate, residual hydrogen peroxide and metal content were evaluated on bleached pulp. The results indicate that the effect of ultrasonic treatment on brightness was dependent on the ultrasound frequency used; the brightness increased slightly at 68 kHz and decreased at 40 and 170 kHz. These results were correlated to the ultrasound effect on the generation of transition metals (copper, iron and manganese) which are responsible for catalytic decomposition of hydrogen peroxide. The influence of metal interference was minimized by using a chelating agent such as diethylene triamine pentaacetic acid (DTPA). With the results obtained in this study we have identified a set of option conditions, e.g. 1000 W, 40 kHz, 1.5 % consistency and 0.2% addition of DTPA prior to the bleaching stage (after ultrasonic pre-treatment) who improve brightness by 2.5 %ISO.

Gas chromatography coupled with mass spectrometric characterization of Curcuma longa: Protection against pathogenic microbes and lipid peroxidation in rat's tissue homogenate.

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Hassan, Waseem; Gul, Shehnaz; Rehman, Shakilla; Kanwal, Farina; Afridi, Muhammad Siddique; Fazal, Hina; Shah, Ziarat; Rahman, Ataur; da Rocha, Joao B T

2016-03-01

The present study was designed to investigate the mineral content and antimicrobial activity of Curcuma Longa extracts and its essential oil. We also determined the lipid peroxidation inhibition activity of the ethanolic extract against sodium nitroprusside (SNP) induced thiobarbituric acid reactive species (TBARS) formation in rat's brain, kidney and liver homogenates. Major constituents of essential oil identified by gas chromatography and mass spectrometry (GCMS) were beta-sesquiphellandrene (38.69%), alpha-curcumene (18.44%) and p-mentha-1,4 (8)-diene (16.29%). Atomic absorption spectroscopy (AAS) was used for the quantitative estimation of Calcium (Ca), Magnesium (Mg), Iron (Fe), Copper (Cu), Zinc (Zn), Chromium (Cr), Nickel (Ni) and Manganese (Mn). The extract showed highest Mg (49.4 mg/l) concentration followed by Ca (35.42 mg/l) and Fe (1.27 mg/l). Our data revealed that the ethanolic extract of Curcuma Longa at 1-10 mg/kg significantly inhibited TBARS production in all tested homogenates. Crude extracts and essential oil were tested against three gram positive bacteria i.e. Bacillus subtilis, Bacillus atrophoeus, Staphylococcus aureus, six gram negative bacteria i.e. Escherichia coli, Klebsiella pneumonias, Salmonella typhi, Pseudomonas aeruginosa, Erwinia carotovora, Agrobacterium tumefaciens and one fungal strain namely Candida albicans by disc diffusion assay. Essential oil showed highest anti-microbial activity as compared to the crude extracts. The present study confirms the significant antimicrobial and antioxidant potential of the studied plant, which can be considered as a diet supplement for a variety of oxidative stress induced or infectious diseases.

Detection of hydrogen peroxide with graphyne

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Majidi, R.; Karami, A. R.

2013-12-01

The effect of hydrogen peroxide on the electronic properties of graphyne has been investigated to explore the possibility of using graphyne based biosensor. We have used density functional theory to study the electronic properties of γ-graphyne in the presence of different number of hydrogen peroxide. The optimal adsorption position, orientation, and distance of hydrogen peroxide adsorbed on the graphyne sheet have been determined by calculating adsorption energy. It is found that γ-graphyne which is an intrinsic semiconductor becomes an n-type semiconductor due to the presence of hydrogen peroxide. The energy band gap of γ-graphyne is decreased by increasing the number of hydrogen peroxide. The results demonstrate that γ-graphyne is a promising candidate for biosensor application because of its electrical sensitivity to hydrogen peroxide.

Dibenzazepin hydrochloride as a new spectrophotometric reagent for determination of hydrogen peroxide in plant extracts.

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Nagaraja, P; Prakash, J S; Asha, S C; Bhaskara, B L; Kumar, S Anil

2012-10-01

A rapid, simple, accurate, and sensitive visible spectrophotometric method for the determination of trace amounts of hydrogen peroxide in acidic buffer medium is reported. The proposed method is based on the oxidative coupling of Ampyrone with dibenzazepin hydrochloride by hydrogen peroxide in the buffer medium of pH 4.0 which is catalyzed by ferrous iron. The blue-colored product formed with maximum absorption at 620 nm was found to be stable for 2 h. Beer's law is obeyed for hydrogen peroxide concentration in the range of 0.03-0.42 μg ml(-1). The optimum reaction conditions and other important optical parameters are reported. The molar absorptive and Sandell's sensitivity are found to be 5.89 × 10(4) mol(-1) cm(-1) and 0.57 g/cm(2), respectively. The interference due to diverse ions and complexing agents was studied. The method is successfully applied to the determination of hydrogen peroxide in green plants satisfactorily.

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

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Koppula, Sushruta; Choi, Dong Kug

2011-07-01

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

Scavenger and antioxidant properties of prenylflavones isolated from Artocarpus heterophyllus.

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Ko, F N; Cheng, Z J; Lin, C N; Teng, C M

1998-07-15

The antioxidant properties of prenylflavones, isolated from Artocarpus heterophyllus Lam., was evaluated in this study. Among them, artocarpine, artocarpetin, artocarpetin A, and cycloheterophyllin diacetate and peracetate had no effect on iron-induced lipid peroxidation in rat brain homogenate. They also did not scavenge the stable free radical 1,1-diphenyl-2-picrylhydrazyl. In contrast, cycloheterophyllin and artonins A and B inhibited iron-induced lipid peroxidation in rat brain homogenate and scavenged 1,1-diphenyl-2-picrylhydrazyl. They also scavenged peroxyl radicals and hydroxyl radicals that were generated by 2,2'-azobis(2-amidinopropane) dihydrochloride and the Fe3+-ascorbate-EDTA-H2O2 system, respectively. However, they did not inhibit xanthine oxidase activity or scavenge superoxide anion, hydrogen peroxide, carbon radical, or peroxyl radicals derived from 2,2'-azobis(2,4-dimethylvaleronitrile) in hexane. Moreover, cycloheterophyllin and artonins A and B inhibited copper-catalyzed oxidation of human low-density lipoprotein, as measured by fluorescence intensity, thiobarbituric acid-reactive substance and conjugated-diene formations and electrophoretic mobility. It is concluded that cycloheterophyllin and artonins A and B serve as powerful antioxidants against lipid peroxidation when biomembranes are exposed to oxygen radicals.

Functional analysis of a novel hydrogen peroxide resistance gene in Lactobacillus casei strain Shirota.

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Serata, Masaki; Kiwaki, Mayumi; Iino, Tohru

2016-11-01

Lactic acid bacteria have a variety of mechanisms for tolerance to oxygen and reactive oxygen species, and these mechanisms differ among species. Lactobacillus casei strain Shirota grows well under aerobic conditions, indicating that the various systems involved in oxidative stress resistance function in this strain. To elucidate the mechanism of oxidative stress resistance in L. casei strain Shirota, we examined the transcriptome response to oxygen or hydrogen peroxide exposure. We then focused on an uncharacterized gene that was found to be up-regulated by both oxygen and hydrogen peroxide stress; we named the gene hprA1 (hydrogen peroxide resistance gene). This gene is widely distributed among lactobacilli. We investigated the involvement of this gene in oxidative stress resistance, as well as the mechanism of tolerance to hydrogen peroxide. Growth of L. casei MS105, an hprA1-disrupted mutant, was not affected by oxygen stress, whereas the survival rate of MS105 after hydrogen peroxide treatment was markedly reduced compared to that of the wild-type. However, the activity of MS105 in eliminating hydrogen peroxide was similar to that of the wild-type. We cloned hprA1 from L. caseiShirota and purified recombinant HprA1 protein from Escherichia coli. We demonstrated that the recombinant HprA1 protein bound to iron and prevented the formation of a hydroxyl radical in vitro. Thus, HprA1 protein probably contributes to hydrogen peroxide tolerance in L. casei strain Shirota by binding to iron in the cells and preventing the formation of a hydroxyl radical.

Problem of the lithium peroxide thermal stability

International Nuclear Information System (INIS)

Nefedov, R A; Ferapontov, Yu A; Kozlova, N P

2016-01-01

The behavior of lithium peroxide and lithium peroxide monohydrate samples under heating in atmospheric air was studied by the method of thermogravimetric analysis (TGA) and differential thermal analysis (DTA). It was found that in the temperature range of 32°C to 82°C the interaction of lithium peroxides and steam with the formation of lithium peroxide monohydrate occurs, which was confirmed chemically and by X-ray Single-qualitative analysis. It was experimentally found that lithium peroxide starts to decompose into the lithium oxide and oxygen in the temperature range of 340 ÷ 348°C. It was established that the resulting thermal decomposition of lithium oxide, lithium peroxide at the temperature of 422°C melts with lithium carbonate eutecticly. The manifestation of polymorphism was not marked(seen or noticed) under the heating of studied samples of lithium peroxide and lithium peroxide monohydrate in the temperature range of 25°C ÷ 34°C. (paper)

Polymerization of aniline in an organic peroxide system by the inverted emulsion process

OpenAIRE

Rao, Palle Swapna; Sathyanarayana, DN; Palaniappan, S

2002-01-01

An inverted emulsion process for the synthesis of the emeraldine salt of polyaniline using a novel oxidizing agent, namely benzoyl peroxide, is described. The polymerization is carried out in a nonpolar solvent in the presence of a functionalized protonic acid (sulfosalicylic acid) as the dopant and an emulsifier (sodium lauryl sulfate). The influence of synthesis conditions such as the duration of the reaction, temperature, concentration of the reactants, etc., on the properties of polyanili...

Chemical composition, antioxidant properties and antimicrobial activity of the essential oil of Murraya paniculata leaves from the mountains of Central Cuba.

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Rodríguez, Elisa Jorge; Ramis-Ramos, Guillermo; Heyden, Yvan Vander; Simó-Alfonso, Ernesto F; Lerma-García, María Jesús; Saucedo-Hernández, Yanelis; Monteagudo, Urbano; Morales, Yeni; Holgado, Beatriz; Herrero-Martínez, José Manuel

2012-11-01

The essential oil of Murraya paniculata L leaves from the mountains of the Central Region of Cuba, obtained by hydrodistillation, was analyzed by gas chromatography-mass spectrometry. Eighteen compounds, accounting for 95.1% of the oil were identified. The major component was beta-caryophyllene (ca. 30%). The antioxidant activity of essential oil was evaluated against Cucurbita seed oil by peroxide, thiobarbituric acid and p-anisidine methods. The essential oil showed stronger antioxidant activity than that of butylated hydroxyanisole and butylated hydroxytoluene, but lower than that of propyl gallate. Moreover, this antioxidant activity was supported by the complementary antioxidant assay in the linoleic acid system and 2, 2'-diphenyl-1-picrylhydrazyl. The essential oil also showed good to moderate inhibitory effects against Klebsiellapneumoniae and Bacillus subtilis.

DNA Phosphorothioate Modification Plays a Role in Peroxides Resistance in Streptomyces lividans

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Daofeng Dai

2016-08-01

Full Text Available DNA phosphorothioation, conferred by dnd genes, was originally discovered in the soil-dwelling bacterium Streptomyces lividans, and thereafter found to exist in various bacterial genera. However, the physiological significance of this sulfur modification of the DNA backbone remains unknown in S. lividans. Our studies indicate that DNA phosphorothioation has a major role in resistance to oxidative stress in the strain. Although Streptomyces species express multiple catalase/peroxidase and organic hydroperoxide resistance genes to protect them against peroxide damage, a wild type strain of S. lividans exhibited two-fold to 10-fold higher survival, compared to a dnd- mutant, following treatment with peroxides. RNA-seq experiments revealed that, catalase and organic hydroperoxide resistance gene expression were not up-regulated in the wild type strain, suggesting that the resistance to oxidative stress was not due to the up-regulation of these genes by DNA phosphorothioation. Quantitative RT-PCR analysis was conducted to trace the expression of the catalase and the organic hydroperoxide resistance genes after peroxides treatments. A bunch of these genes were activated in the dnd- mutant rather than the wild type strain in response to peroxides. Moreover, the organic hydroperoxide peracetic acid was scavenged more rapidly in the presence than in the absence of phosphorothioate modification, both in vivo and in vitro. The dnd gene cluster can be up-regulated by the disulfide stressor diamide. Overall, our observations suggest that DNA phosphorothioate modification functions as a peroxide resistance system in S. lividans.

HYDROGEN PEROXIDE PRODUCTION ACTIVITY AND ADHESIVE PROPERTIES OF AEROCOCCI, ISOLATED IN WOMEN

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Stepanskyi D.O.

2017-06-01

Full Text Available Introduction. Antagonistic activity of probiotic microorganisms against other species of bacteria is an important mechanism of their ecology and it is widely used in practice. This activity is inherent in many heme-deficient bacteria, which include aerococci, and can be composed of several components: the production of organic acids, antibiotics, lysozyme, hydrogen peroxide and others. Ability to produce hydrogen peroxide under aerobic conditions and in a state of relative anaerobiosis was established in aerococci. They were divided into strong and weak producers, depending on the amount of peroxides. Lack of data about peroxide-productive ability of aerococci, isolated from the lower genital tract of women, as well as a proven mechanism of hydrogen peroxide excretion in the oxidation of lactic acid, led to need in studying the aerococci hydrogen peroxide production level, to create autobacterial drugs, based on aerococci symbiont strains for sanitation of birth canal. Colonization resistance of the vaginal mucous and normal microflora value depends largely on the degree of adhesion of microbial cells to the mucosal surface. Along with numerous studies of lactobacilli adhesive properties to the vaginal epithelium, there are no data on the adsorption capacity of aerococci to the vaginal epithelial cells. Material and methods. 18 aerococci resident strains and 1 museum strain were explored in total. Presence and quantity of autosymbiont aerococci content in different parts of the birth tract (cervical canal, vagina, external genitalia skin (EGS and perineum was studied in 44 healthy women. Isolation and identification of aerococci from the women body was conducted by the method, taking into account growth on selective indicator medium, growth and biochemical activity in environments with selenium and tellurium salts, lactate oxidase and superoxide dismutase activity. Hydrogen peroxide was determined by iodometric method. Hydrogen peroxide

Effects of olive oil and its fractions on oxidative stress and the liver's fatty acid composition in 2,4-Dichlorophenoxyacetic acid-treated rats

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Ellouz Meriem

2010-10-01

Full Text Available Abstract Background Olive oil's beneficial effects are not only related to its high content of oleic acid, but also to the antioxidant potential of its polyphenols. In this study, we assess the effects of virgin olive oil and its fractions on 2,4-D- induced oxidative damage in the liver of rats. Methods Male Wistar rats were randomly divided into eight groups of ten each: (C a control group, (D group that received 2,4-D (5 mg/kg b.w., (D/EVOO group treated with 2,4-D plus extra virgin olive oil, (D/OOHF group that received 2,4-D plus hydrophilic fraction, (D/OOLF group treated with 2,4-D plus lipophilic fraction, (EVOO group that received only extra virgin olive oil, (OOHF group given hydrophilic fraction and (OOLF group treated with lipophilic fraction. These components were daily administered by gavage for 4 weeks. Results A significant liver damage was observed in rats treated with 2,4-D via increased serum levels of transaminases and alkaline phosphatase, hepatic lipid peroxidation and decreased hepatic antioxidant enzyme activities, namely, superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase. The liver's fatty acid composition was also significantly modified with 2,4-D exposure. However, extra virgin olive oil and hydrophilic fraction intake during 2,4-D treatment induced a significant increase in the antioxidant enzyme activities and a decrease in the conjugated dienes (CD and thiobarbituric acid-reactive substances (TBARs levels in the liver. The lipophilic fraction supplemented to 2,4-D- treated rats did not show any improvement in the liver oxidative status while a marked improvement was detected in the hepatic fatty acid composition of rats supplemented with olive oil and the two fractions. Conclusion We concluded that the protective effect of olive oil against oxidative damage induced by 2,4-D is mainly related to the antioxidant potential of its hydrophilic fraction.

In-Vitro Radio protective Role of Ferulic Acid in Cultured Lymphocytes

International Nuclear Information System (INIS)

Ahmed, M.M.; Al Fateh, N.M.; Tawfik, S.S.

2010-01-01

Ferulic acid (FA), C 10 H 10 O 4 is the most abundant, ubiquitous hydroxycinnamic acid derived from photochemical phenolic compounds. It is a major constituent of fruits and vegetables such as orange, tomato, carrot, sweet corn and rice bran. Gamma rays generate hydroxyl radicals in cells and cellular DNA damage which leads to genotoxicity and chromosome aberrations. To establish most effective protective support, we used two different concentrations of FA (5 and 10 μg/ ml) and 2 Gy dose of gamma-radiation. Cytogenetic analysis was evaluated using the analysis of structural chromosome aberration (CA) and cytokinesis block micronucleus assay (CBMN). The level of lipid peroxidation analyzed as thiobarbituric acid reactive substances (TBARS), total glutathione (GSH), the enzyme activities of lymphocytes defence mechanism: Superoxide dismutase (SOD), Catalase (CAT) and Glutathione peroxidase (GPx) were determined. The result obtained by all endpoints indicates acceptable toxicity profiles of FA in-vitro when compared with normal lymphocytes; irradiation at 2 Gy increased the MN and CA frequencies. Treatment with FA for 30 min before radiation exposure resulted in a significant decline both of MN and CA yields as FA concentration increased. The levels of TBARS and GSH were altered significantly whereas the levels of the enzymatic antioxidants were decreased in gamma-irradiated lymphocytes. Pretreatment with 10 μg/ ml of FA has attenuated the toxic effects of radiation more than FA (5 μg/ ml) by reduction in the TBARS level, restoration GSH contents and prevented the decreases in the radiation-induced SOD, CAT and GPx activities. These results lead us to the conclusion that FA has antimutagenic effect and benefit as a radio protector against oxidative stress involved by gamma-rays exposure

Observation of atmospheric peroxides during Wangdu Campaign 2014 at a rural site in the North China Plain

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Y. Wang

2016-09-01

Full Text Available Measurements of atmospheric peroxides were made during Wangdu Campaign 2014 at Wangdu, a rural site in the North China Plain (NCP in summer 2014. The predominant peroxides were detected to be hydrogen peroxide (H2O2, methyl hydroperoxide (MHP and peroxyacetic acid (PAA. The observed H2O2 reached up to 11.3 ppbv, which was the highest value compared with previous observations in China at summer time. A box model simulation based on the Master Chemical Mechanism and constrained by the simultaneous observations of physical parameters and chemical species was performed to explore the chemical budget of atmospheric peroxides. Photochemical oxidation of alkenes was found to be the major secondary formation pathway of atmospheric peroxides, while contributions from alkanes and aromatics were of minor importance. The comparison of modeled and measured peroxide concentrations revealed an underestimation during biomass burning events and an overestimation on haze days, which were ascribed to the direct production of peroxides from biomass burning and the heterogeneous uptake of peroxides by aerosols, respectively. The strengths of the primary emissions from biomass burning were on the same order of the known secondary production rates of atmospheric peroxides during the biomass burning events. The heterogeneous process on aerosol particles was suggested to be the predominant sink for atmospheric peroxides. The atmospheric lifetime of peroxides on haze days in summer in the NCP was about 2–3 h, which is in good agreement with the laboratory studies. Further comprehensive investigations are necessary to better understand the impact of biomass burning and heterogeneous uptake on the concentration of peroxides in the atmosphere.

Conversion of Aryl Iodides into Aryliodine(III Dichlorides by an Oxidative Halogenation Strategy Using 30% Aqueous Hydrogen Peroxide in Fluorinated Alcohol

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Ajda Podgoršek

2010-04-01

Full Text Available Oxidative chlorination with HCl/H2O2 in 1,1,1-trifluoroethanol was used to transform aryl iodides into aryliodine(III dihalides. In this instance 1,1,1-trifluoroethanol is not only the reaction medium, but is also an activator of hydrogen peroxide for the oxidation of hydrochloric acid to molecular chlorine. Aryliodine(III dichlorides were formed in 72–91% isolated yields in the reaction of aryl iodides with 30% aqueous hydrogen peroxide and hydrochloric acid at ambient temperature. A study of the effect that substituents on the aromatic ring have on the formation and stability of aryliodine(III dichlorides shows that the transformation is easier to achieve in the presence of the electron-donating groups (i.e. methoxy, but in this case the products rapidly decompose under the reported reaction conditions to form chlorinated arenes. The results suggest that oxidation of hydrogen chloride with hydrogen peroxide is the initial reaction step, while direct oxidation of aryl iodide with hydrogen peroxide is less likely to occur.

Asbestos induced oxidative injury to DNA.

Science.gov (United States)

Mahmood, N; Khan, S G; Ali, S; Athar, M; Rahman, Q

1993-06-01

DNA-damaging effects of asbestos in the presence of organic peroxides and hydroperoxides were investigated. The destabilization of the secondary structure of DNA, damage to deoxyribose sugar and DNA fidelity were measured, respectively, by S-1 nuclease hydrolysis, the formation of thiobarbituric acid (TBA)-reacting species and a melting temperature (Tm) profile using calf thymus DNA. S-1 nuclease hydrolysis and Tm determinations have shown that the presence of benzoylperoxide (BOOB), cumene hydroperoxide (COOH) or tertiary-butyl hydroperoxide (t-BOOH) increased asbestos-mediated DNA damage by a large factor compared either to asbestos alone or to peroxide or hydroperoxide alone. However, no formation of TBA-reacting species could be observed in this system. The quenchers of reactive oxygen species (ROS) afforded protection against DNA damage. These results suggest that asbestos in the presence of organic peroxides and hydroperoxides damage the DNA which is mediated by the generation of oxygen free radicals. The significance of these results in relation to the development of cancer of the respiratory tract among the asbestos exposed population is discussed.

Spectroscopic studies of europium-tetracyclines complexes and their applications in detection of hydrogen peroxide and urea peroxide

International Nuclear Information System (INIS)

Grasso, Andrea Nastri

2010-01-01

In this work were studied the spectroscopic properties of trivalent europium ion complexed with components of tetracycline family, chlorotetracycline, oxytetracycline and metacycline, in the presence of hydrogen peroxide and urea peroxide. Optical parameters were obtained such as absorption, emission, lifetime and calibration curves were constructed for luminescence spectra. Experiments were carried out with both inorganic compounds and europium-tetracyclines complexes in order to verify possible interferences. Studies for glucose determination were also described using europium-tetracyclines complexes as biosensors. Results show that europium tetracyclines complexes emit a narrow band in the visible region and, in the presence of hydrogen peroxide or urea peroxide there is a greater enhancement in their luminescence and lifetime. Thus, europium-tetracyclines complexes studied can be used as biosensors for hydrogen and urea peroxides determination as a low cost and room temperature method. An indirect method for glucose determination was studied by adding glucose oxidase enzyme in europium-tetracyclines complex in the presence of glucose promoting as product hydrogen peroxide. (author)

21 CFR 529.1150 - Hydrogen peroxide.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Hydrogen peroxide. 529.1150 Section 529.1150 Food... DRUGS, FEEDS, AND RELATED PRODUCTS CERTAIN OTHER DOSAGE FORM NEW ANIMAL DRUGS § 529.1150 Hydrogen peroxide. (a) Specifications. Each milliliter of solution contains 396.1 milligrams (mg) hydrogen peroxide...

Plutonium recovery from incinerator ash and centrifuge sludge by peroxide fusion

International Nuclear Information System (INIS)

Partridge, J.A.; Wheelwright, E.J.

1975-05-01

A technique was demonstrated for solubilizing the plutonium contained in incinerator ash and in other waste solids (such as solids accumulated by centrifugation after solvent extraction contacts in the plutonium reclamation facility at Hanford). A sodium hydroxide--sodium peroxide fusion is performed on the Pu-containing solids. The cooled melt is then dissolved in dilute nitric acid. Mild steel cans were used as ''single use'' crucibles for the fusions. Both the can and the cooled melt are dissolved in nitric acid. Fusion tests were conducted on three different cans of incinerator ash and on one can of centrifuge sludge. The series of tests demonstrated that a caustic-peroxide fusion treatment can yield 95 percent or greater recovery of plutonium from these waste solids. In most cases, quantitative recovery of the plutonium can probably be achieved by recycling the residual solids obtained in aqueous dissolution of the cooled fusion mixture. Tests with some of the incinerator ash and with the centrifuge sludge resulted in gelatinous precipitates which were difficult to separate from the nitric acid dissolver solutions. These gelatinous precipitates present what is probably the major problem to be overcome in the use of this Pu recovery method. Techniques need to be examined for making these residual solids less difficult to separate from the dissolver solution. (U.S.)

Systemic exposure to benzoic acid and hippuric acid following topical application of clindamycin 1%/benzoyl peroxide 3% fixed-dose combination gel in Japanese patients with acne vulgaris.

Science.gov (United States)

Ino, Hiroko; Takahashi, Naoki; Saenz, Alessandra Alio; Wakamatsu, Akira; Hashimoto, Hirofumi; Nakahara, Norie; Hasegawa, Setsuo

2015-01-01

Clindamycin 1%/benzoyl peroxide 3% fixed-dose combination gel (CLDM/BPO3%) is a topical product for the treatment of acne vulgaris. In this study, plasma and urine concentrations of benzoic acid (BA) and hippuric acid (HA) were analyzed to estimate the pharmacokinetics (PK) of BPO after application of CLDM/BPO3% twice-daily for 7 days in Japanese patients with acne vulgaris. Seven-day repeated application of CLDM/BPO3% appears to be safe in this patient population. Concentrations of plasma and urine BA were below the limit of quantification before and after repeated application in most of the 12 adult male patients. Mean difference in Cmax and AUC0-last for plasma HA indicated increased exposures after repeated application, but with wide 90% confidence intervals. Mean Ae0-12 for urine HA was similar before and after repeated application. Repeated application of CLDM/BPO3% is thus unlikely to result in accumulation of BA and HA. The study suggests negligible systemic exposure to BPO metabolites from CLDM/BPO3% after 7-day repeated application in male patients with acne vulgaris. © 2014, The American College of Clinical Pharmacology.

Bromate Formation Characteristics of UV Irradiation, Hydrogen Peroxide Addition, Ozonation, and Their Combination Processes

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Naoyuki Kishimoto

2012-01-01

Full Text Available Bromate formation characteristics of six-physicochemical oxidation processes, UV irradiation, single addition of hydrogen peroxide, ozonation, UV irradiation with hydrogen peroxide addition (UV/H2O2, ozonation with hydrogen peroxide addition (O3/H2O2, and ozonation with UV irradiation (O3/UV were investigated using 1.88 μM of potassium bromide solution with or without 6.4 μM of 4-chlorobenzoic acid. Bromate was not detected during UV irradiation, single addition of H2O2, and UV/H2O2, whereas ozone-based treatments produced . Hydroxyl radicals played more important role in bromate formation than molecular ozone. Acidification and addition of radical scavengers such as 4-chlorobenzoic acid were effective in inhibiting bromate formation during the ozone-based treatments because of inhibition of hydroxyl radical generation and consumption of hydroxyl radicals, respectively. The H2O2 addition was unable to decompose 4-chlorobenzoic acid, though O3/UV and O3/H2O2 showed the rapid degradation, and UV irradiation and UV/H2O2 showed the slow degradation. Consequently, if the concentration of organic contaminants is low, the UV irradiation and/or UV/H2O2 are applicable to organic contaminants removal without bromate formation. However, if the concentration of organic contaminants is high, O3/H2O2 and O3/UV should be discussed as advanced oxidation processes because of their high organic removal efficiency and low bromate formation potential at the optimum condition.

Astaxanthin Restrains Nitrative-Oxidative Peroxidation in Mitochondrial-Mimetic Liposomes: A Pre-Apoptosis Model

Science.gov (United States)

Mano, Camila M.; Cardozo, Karina H. M.; Colepicolo, Pio; Bechara, Etelvino J. H.

2018-01-01

Astaxanthin (ASTA) is a ketocarotenoid found in many marine organisms and that affords many benefits to human health. ASTA is particularly effective against radical-mediated lipid peroxidation, and recent findings hypothesize a “mitochondrial-targeted” action of ASTA in cells. Therefore, we examined the protective effects of ASTA against lipid peroxidation in zwitterionic phosphatidylcholine liposomes (PCLs) and anionic phosphatidylcholine: phosphatidylglycerol liposomes (PCPGLs), at different pHs (6.2 to 8.0), which were challenged by oxidizing/nitrating conditions that mimic the regular and preapoptotic redox environment of active mitochondria. Pre-apoptotic conditions were created by oxidized/nitr(osyl)ated cytochrome c and resulted in the highest levels of lipoperoxidation in both PCL and PCPGLs (pH 7.4). ASTA was less protective at acidic conditions, especially in anionic PCPGLs. Our data demonstrated the ability of ASTA to hamper oxidative and nitrative events that lead to cytochrome c-peroxidase apoptosis and lipid peroxidation, although its efficiency changes with pH and lipid composition of membranes. PMID:29649159

Assessment of a colorimetric method for the measurement of low concentrations of peracetic acid and hydrogen peroxide in water.

Science.gov (United States)

Domínguez-Henao, Laura; Turolla, Andrea; Monticelli, Damiano; Antonelli, Manuela

2018-06-01

The recent growing interest in peracetic acid (PAA) as disinfectant for wastewater treatment demands reliable and readily-available methods for its measurement. In detail, the monitoring of PAA in wastewater treatment plants requires a simple, accurate, rapid and inexpensive measurement procedure. In the present work, a method for analyzing low concentrations of PAA, adapted from the US EPA colorimetric method for total chlorine, is assessed. This method employs N,N-diethyl-p-phenylelnediamine (DPD) in the presence of an excess of iodide in a phosphate buffer system. Pink colored species are produced proportionally to the concentration of PAA in the sample. Considering that PAA is available commercially as an equilibrium solution of PAA and hydrogen peroxide (H 2 O 2 ), a measurement method for H 2 O 2 is also investigated. This method, as the one for the determination of PAA, is also based on the oxidation of iodide to iodine, with the difference that ammonium molybdate Mo(VI) is added to catalyze the oxidation reaction between H 2 O 2 and iodide, quantifying the total peroxides (PAA+ H 2 O 2 ). The two methods are suitable for concentration ranges from about 0.1-1.65 mg L -1 and from about 0.3-3.3 mg L -1 , respectively for PAA and H 2 O 2 . Moreover, the work elucidates some relevant aspects related to the operational conditions, kinetics and the possible interference of H 2 O 2 on PAA measurement. Copyright © 2018 Elsevier B.V. All rights reserved.

Radioprotective effect of Panax ginseng on the phosphatases and lipid peroxidation level in testes of Swiss albino mice

Energy Technology Data Exchange (ETDEWEB)

Kumar M.; Sharma M.K.; Saxena P.S.; Kumar A. [Rajasthan Univ., Jaipur (India)

2003-03-01

The Panax ginseng has been used as traditional medicine for past several years among oriental people. The present investigation has been made to assess the radioprotective efficacy of ginseng root extract in the testicular enzymes of Swiss albino mice. The Swiss albino mice were divided into different groups. Ginseng treated group: The animals were administered 10 mg/kg body weight ginseng root extract intraperitoneal (i.p.). Radiation treated group: The animals were exposed to 8 Gy gamma radiation at the dose rate of 1.69 Gy/min at the distance of 80 cm. Combination group: Animals were administered ginseng extract continuously for 4 d and on 4th day they were irradiated to 8 Gy gamma radiation after 30 min of extract administration. The animals from above groups were autopsied on day 1, 3, 7, 14 and 30. Biochemical estimations of acid and alkaline phosphatases and Lipid peroxidation (LPO) in testes were done. In ginseng treated group acid and alkaline phosphatases activity and LPO level did not show any significant alteration. In irradiated animals there was a significant increase in acid phosphatase activity and LPO level. However, significant decline in alkaline phosphatase activity was observed. The treatment of ginseng before irradiation causes significant decrease in acid phosphatase and LPO level and significant increase in alkaline phosphatase activity. One of the cause of radiation damage is lipid peroxidation. Due to lipid peroxidation, lysosomal membrane permeability alters and thus results in release of hydrolytic enzymes. So, an increase in acid phosphatase was noticed after radiation treatment. The alkaline phosphatase activity is associated with membrane permeability and different stages of spermatogenesis. Due to membrane damage and depletion of germ cells of testes after irradiation the enzyme activity was decreased. Ginseng markedly inhibits lipid peroxidation. It acts in indirect fashion to protect radical processes by inhibition of initiation of

Radioprotective effect of Panax ginseng on the phosphatases and lipid peroxidation level in testes of Swiss albino mice

International Nuclear Information System (INIS)

Kumar, M.; Sharma, M.K.; Saxena, P.S.; Kumar, A.

2003-01-01

The Panax ginseng has been used as traditional medicine for past several years among oriental people. The present investigation has been made to assess the radioprotective efficacy of ginseng root extract in the testicular enzymes of Swiss albino mice. The Swiss albino mice were divided into different groups. Ginseng treated group: The animals were administered 10 mg/kg body weight ginseng root extract intraperitoneal (i.p.). Radiation treated group: The animals were exposed to 8 Gy gamma radiation at the dose rate of 1.69 Gy/min at the distance of 80 cm. Combination group: Animals were administered ginseng extract continuously for 4 d and on 4th day they were irradiated to 8 Gy gamma radiation after 30 min of extract administration. The animals from above groups were autopsied on day 1, 3, 7, 14 and 30. Biochemical estimations of acid and alkaline phosphatases and Lipid peroxidation (LPO) in testes were done. In ginseng treated group acid and alkaline phosphatases activity and LPO level did not show any significant alteration. In irradiated animals there was a significant increase in acid phosphatase activity and LPO level. However, significant decline in alkaline phosphatase activity was observed. The treatment of ginseng before irradiation causes significant decrease in acid phosphatase and LPO level and significant increase in alkaline phosphatase activity. One of the cause of radiation damage is lipid peroxidation. Due to lipid peroxidation, lysosomal membrane permeability alters and thus results in release of hydrolytic enzymes. So, an increase in acid phosphatase was noticed after radiation treatment. The alkaline phosphatase activity is associated with membrane permeability and different stages of spermatogenesis. Due to membrane damage and depletion of germ cells of testes after irradiation the enzyme activity was decreased. Ginseng markedly inhibits lipid peroxidation. It acts in indirect fashion to protect radical processes by inhibition of initiation of

Flow injection determination of hydrogen peroxide using catalytic effect of cobalt(II) ion on a dye formation reaction.

Science.gov (United States)

Kurihara, Makoto; Muramatsu, Miyuki; Yamada, Mari; Kitamura, Naoya

2012-07-15

A novel flow injection photometric method was developed for the determination of hydrogen peroxide in rainwater. This method is based on a cobalt(II)-catalyzed oxidative coupling of 3-methyl-2-benzothiazolinone hydrazone (MBTH) with N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3,5-dimethoxyaniline (DAOS) as a modified Trinder's reagent to produce intensely colored dye (λ(max)=530nm) in the presence of hydrogen peroxide at pH 8.4. In this method, 1,2-dihydroxy-3,5-benzenedisulfonic acid (Tiron) acted as an activator for the cobalt(II)-catalyzed reaction and effectively increased the peak height for hydrogen peroxide. The linear calibration graphs were obtained in the hydrogen peroxide concentration range 5×10(-8) to 2.2×10(-6)mol dm(-3) at a sampling rate of 20h(-1). The relative standard deviations for ten determinations of 2.2×10(-6) and 2×10(-7)mol dm(-3) hydrogen peroxide were 1.1% and 3.7%, respectively. The proposed method was successfully applied to the determination of hydrogen peroxide in rainwater samples and the analytical results agreed fairly well with the results obtained by different two reference methods; peroxidase method and hydrogen peroxide electrode method. Copyright © 2012 Elsevier B.V. All rights reserved.

Ultrasound augmented leaching of nickel sulfate in sulfuric acid and hydrogen peroxide media.

Science.gov (United States)

Li, Haoyu; Li, Shiwei; Peng, Jinhui; Srinivasakannan, Chandrasekar; Zhang, Libo; Yin, Shaohua

2018-01-01

A new method of preparation high purity nickel sulfate assisted by ultrasonic was studied. The process mechanism was analyzed by Inductively Coupled Plasma (ICP), X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Energy dispersive X-ray spectrometry (EDS).The reaction mechanisms of oxidizing leaching and ultrasonic leaching were explored, respectively. Results showed that ultrasonic treatment peel off the oxide film on the surface of nickel. The leachate under strongly agitated, the yield rate of nickel sulfate was accelerate. And the reaction area was increased by the cavitation effect, the liquid-solid reaction was promoted, and the activation energy was reduced. The leaching rate of nickel reached 46.29% by conventional leaching, which takes about 5h. Under the same conditions, the ultrasonic leaching rate reached 40%, only half of the conventional leaching time. Concentration of leaching agent, reaction temperature, ultrasonic power, leaching time had significant effect on the enhancement of the leaching reaction with ultrasonic radiation. The leaching rate of 60.41% under the optimum experiment conditions as follows: sulfuric acid concentration 30%, hydrogen peroxide 10%, leaching temperature 333K, ultrasonic power 200W and leaching time 4h. The kinetic study of the system was investigated, and the reaction rates of conventional leaching and ultrasonic leaching were controlled by diffusion, and the apparent activation energies were 16.2kJ/mol and 11.83kJ/mol. Copyright © 2017. Published by Elsevier B.V.

High-Intensity Exercise Induced Oxidative Stress and Skeletal Muscle Damage in Postpubertal Boys and Girls: A Comparative Study.

Science.gov (United States)

Pal, Sangita; Chaki, Biswajit; Chattopadhyay, Sreya; Bandyopadhyay, Amit

2018-04-01

Pal, S, Chaki, B, Chattopadhyay, S, and Bandyopadhyay, A. High-intensity exercise induced oxidative stress and skeletal muscle damage in post-pubertal boys and girls: a comparative study. J Strength Cond Res 32(4): 1045-1052, 2018-The purpose of this study was to examine the sex variation in high-intensity exercise induced oxidative stress and muscle damage among 44 sedentary postpubertal boys and girls through estimation of postexercise release pattern of muscle damage markers like creatine kinase, lactate dehydrogenase (LDH), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and oxidative stress markers like extent of lipid peroxidation (thiobarbituric acid-reactive substances) and catalase activity. Muscle damage markers like creatine kinase, LDH, ALT, and AST were measured before, immediately after, and 24 and 48 hours after high-intensity incremental treadmill running. Oxidative stress markers like thiobarbituric acid-reactive substances and catalase activity were estimated before and immediately after the exercise. Lipid peroxidation and serum catalase activity increased significantly in both groups after exercise (p exercise level at 24 and 48 hours after exercise in both the sexes, (p exercise, the pattern of postexercise release of these markers were found to be similar in both the groups. Accordingly, it has been concluded from the present investigation that high-intensity exercise induces significant oxidative stress and increases indices of skeletal muscle damage in both postpubertal girls and boys. However, postpubertal girls are relatively better protected from oxidative stress and muscle damage as compared to the boys of similar age and physical activity level. It is further evident that sex difference may not be apparent for all the biomarkers of muscle damage in this age group.

Mitochondrial Protection and Anti-aging Activity of Astragalus Polysaccharides and Their Potential Mechanism

Directory of Open Access Journals (Sweden)

Xiao-Juan Xin

2012-02-01

Full Text Available The current study was performed to investigate mitochondrial protection and anti-aging activity of Astragalus polysaccharides (APS and the potential underlying mechanism. Lipid peroxidation of liver and brain mitochondria was induced by Fe2+–Vit C in vitro. Thiobarbituric acid (TBA colorimetry was used to measure the content of thiobarbituric acid reactive substances (TBARS. Mouse liver mitochondrial permeability transition (PT was induced by calcium overload in vitro and spectrophotometry was used to measure it. The scavenging activities of APS on superoxide anion (O2•－ and hydroxyl radical (•OH, which were produced by reduced nicotinamide adenine dinucleotide (NADH—N-Methylphenazonium methyl sulfate (PMS and hydrogen peroxide (H2O2–Fe2+ system respectively, were measured by 4-nitrobluetetrazolium chloride (NBT reduction and Fenton reaction colorimetry respectively. The Na2S2O3 titration method was used to measure the scavenging activities of APS on H2O2. APS could inhibit TBARS production, protect mitochondria from PT, and scavenge O2•－, •OH and H2O2 significantly in a concentration-dependent manner respectively. The back of the neck of mice was injected subcutaneously with D-galactose to induce aging at a dose of 100 mg/kg/d for seven weeks. Moreover, the activities of catalase (CAT, surperoxide dismutase (SOD and glutathione peroxidase (GPx and anti-hydroxyl radical which were assayed by using commercial monitoring kits were increased significantly in vivo by APS. According to this research, APS protects mitochondria by scavenging reactive oxygen species (ROS, inhibiting mitochondrial PT and increasing the activities of antioxidases. Therefore, APS has the effect of promoting health.

PENGARUH PERENDAMAN DAGING PRA KYURING DALAM JUS DAUN SIRIH TERHADAP KETENGIKAN DAN SIFAT ORGANOLEPTIK DENDENG SAPI SELAMA PENYIMPANAN [The Effect of Soaking of Beef in Betle (Piper betle L Leaf Juice Prior to Curing on Rancidity and Sensory Characteristics of Beef “Dendeng” During Storage

Directory of Open Access Journals (Sweden)

Yuli Rohidayah 2

2002-04-01

Full Text Available The research was carried out to determine the effect of soaking of beef in betle (Piper betle L leaf juice prior to curing on peroxide level, thiobarbituric acid (TBA score, and sensory characteristics of beef “dendeng” during 1-3 months storage. The result in showed that soaking in 10% of betle leaf juice resulted in “dendeng” with peroxide level of 8.69 meq/kg which was significantly lower than that of “dendeng” without soaking. TBA scores of “dendeng” soaked in 10% betle leaf juice after 1, 2, and 3 months storage were 0.0131, 0.0159, and 0.0168 μ mole MA/kg, respectively. These scores were lower than that of threshold score of food rancidity (18 μ mole MA/kg. Sensory characteristics (color, taste, and aroma of “dendeng” during storage were accepted well by the panellists.

Dissolution of ion exchange resin by hydrogen peroxide

International Nuclear Information System (INIS)

Lee, S.C.

1981-08-01

The resin dissolution process was conducted successfully in full-scale equipment at the SRL Semiworks. A solution containing 0.001M Fe 2+ , or Fe 3+ , and 3 vol % H 2 O 2 in 0.1M HNO 3 is sufficient to dissolve up to 40 vol % resin slurry (Dowex 50W-X8). Foaming and pressurization can be eliminated by maintaining the dissolution temperature below 99 0 C. The recommended dissolution temperature range is 85 to 90 0 C. Premixing hydrogen peroxide with all reactants will not create a safety hazard, but operating with a continual feed of hydrogen peroxide is recommended to control the dissolution rate. An air sparging rate of 1.0 to 1.5 scfm will provide sufficient mixing. Spent resin from chemical separation contains DTPA (diethylenetriaminepentaacetic acid) residue, and the resin must be washed with 0.1M NH 4 OH to remove excess DTPA before dissolution. Gamma irradiation of resin up to 4 kW-hr/L did not change the dissolution rate significantly

Effects of acetic acid and hydrogen peroxide application during defeathering on the microbiological quality of broiler carcasses prior to evisceration.

Science.gov (United States)

Dickens, J A; Whittemore, A D

1997-04-01

The microbiological quality and skin appearance of New York dressed broiler carcasses were determined in two separate experiments after a water control, acetic acid, or H2O2 spray during defeathering. Broilers were picked up from a local processor and transported in coops to the pilot facility. In both experiments, commercial processing parameters were followed up to the defeathering step. After feather removal, the vents of all carcasses were blocked with a cotton plug to prevent contamination of the whole carcass rinse diluent with fecal material from the lower gut. The neck and feet were removed, and the carcasses were placed in individual plastic bags in preparation for a whole carcass rinse. Results showed a statistically significant reduction (P < 0.05) in the log10 total aerobic plate counts for carcasses treated with 1% acetic acid in comparison to the water control (log10 cfu counts = 3.93 and 4.53, respectively). No differences were observed in skin appearance due to the 1% acid treatment. The addition of 0.5, 1, or 1.5% H2O2 to spray waters had no effect on microbiological quality of the carcasses when compared to the water control (4.92, 5.01, 4.91, and 4.99 log10 counts, respectively). The skin of carcasses treated with hydrogen peroxide, regardless of the concentration was bleached and bloated.

Phytoproteins in green leaves as building blocks for photosynthesis of gold nanoparticles: An efficient electrocatalyst towards the oxidation of ascorbic acid and the reduction of hydrogen peroxide.

Science.gov (United States)

Megarajan, Sengan; Ayaz Ahmed, Khan Behlol; Rajendra Kumar Reddy, G; Suresh Kumar, P; Anbazhagan, Veerappan

2016-02-01

Herein, we present a simple and green method for the synthesis of gold nanoparticles (AuNPs) using the phytoproteins of spinach leaves. Under ambient sunlight irradiation, the isolated phytoprotein complex from spinach leaves reduces the gold chloride aqueous solution and stabilizes the formed AuNPs. As prepared nanoparticles were characterized by UV-visible spectroscopy, Fourier transform infra-red (FTIR) spectroscopy, zeta potential, transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDS). The surface plasmon resonance (SPR) maximum for AuNPs was observed at 520 nm. The zeta potential value estimated for the AuNPs is -27.0 mV, indicating that the NPs are well separated. Transmission electron micrographs revealed that the particles are spherical in nature with the size range from 10 to 15 nm. AuNPs act as a catalyst in the degradation of an azo dye, methyl orange in an aqueous environment. The reduction rate was determined to be pseudo-first order. Electrocatalytic efficiency of the synthesized AuNPs via this green approach was studied by chronoamperometry using ascorbic acid and hydrogen peroxide as a model compound for oxidation and reduction, respectively. Electrocatalytic studies indicate that the gold nanoparticles can be used to detect ascorbic acid and hydrogen peroxide in micromolar concentrations with response time less than 3s. Copyright © 2015 Elsevier B.V. All rights reserved.

The kinetic study of oxidation of iodine by hydrogen peroxide

Energy Technology Data Exchange (ETDEWEB)

Cantrel, L [Institut de Protection et de Surete Nucleaire, IPNS, CEN Cadarache, Saint Paul lez Durance (France); Chopin, J [Laboratoire d` Electrochimie Inorganique, ENSSPICAM, Marseille (France)

1996-12-01

Iodine chemistry is one of the most important subjects of research in the field of reactor safety because this element can form volatile species which represent a biological hazard for environment. As the iodine and the peroxide are both present in the sump of the containment in the event of a severe accident on a light water nuclear reactor, it can be important to improve the knowledge on the reaction of oxidation of iodine by hydrogen peroxide. The kinetics of iodine by hydrogen peroxide has been studied in acid solution using two different analytical methods. The first is a UV/Vis spectrophotometer which records the transmitted intensity at 460 nm as a function of time to follow the decrease of iodine concentration, the second is an amperometric method which permits to record the increase of iodine+1 with time thanks to the current of reduction of iodine+1 to molecular iodine. The iodine was generated by Dushman reaction and the series of investigations were made at 40{sup o}C in a continuous stirring tank reactor. The influence of the initial concentrations of iodine, iodate, hydrogen peroxide, H{sup +} ions has been determined. The kinetics curves comprise two distinct chemical phases both for molecular iodine and for iodine+1. The relative importance of the two processes is connected to the initial concentrations of [I{sub 2}], [IO{sub 3}{sup -}], [H{sub 2}O{sub 2}] and [H{sup +}]. A rate law has been determined for the two steps for molecular iodine. (author) figs., tabs., 22 refs.

The kinetic study of oxidation of iodine by hydrogen peroxide

International Nuclear Information System (INIS)

Cantrel, L.; Chopin, J.

1996-01-01

Iodine chemistry is one of the most important subjects of research in the field of reactor safety because this element can form volatile species which represent a biological hazard for environment. As the iodine and the peroxide are both present in the sump of the containment in the event of a severe accident on a light water nuclear reactor, it can be important to improve the knowledge on the reaction of oxidation of iodine by hydrogen peroxide. The kinetics of iodine by hydrogen peroxide has been studied in acid solution using two different analytical methods. The first is a UV/Vis spectrophotometer which records the transmitted intensity at 460 nm as a function of time to follow the decrease of iodine concentration, the second is an amperometric method which permits to record the increase of iodine+1 with time thanks to the current of reduction of iodine+1 to molecular iodine. The iodine was generated by Dushman reaction and the series of investigations were made at 40 o C in a continuous stirring tank reactor. The influence of the initial concentrations of iodine, iodate, hydrogen peroxide, H + ions has been determined. The kinetics curves comprise two distinct chemical phases both for molecular iodine and for iodine+1. The relative importance of the two processes is connected to the initial concentrations of [I 2 ], [IO 3 - ], [H 2 O 2 ] and [H + ]. A rate law has been determined for the two steps for molecular iodine. (author) figs., tabs., 22 refs

STUDY OF AZOSPIRILLUM LECTINS INFLUENCE ON HYDROGEN PEROXIDE PRODUCTION IN WHEAT-ROOTS

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Alen’kina S.A.

2009-12-01

Full Text Available It was found that two cell-surface lectins isolated from the nitrogen-fixing soil bacterium Azospirillum brasilense Sp7 and from its mutant defective in lectin activity, A. brasilense Sp7.2.3 can stimulate rapid formation of hydrogen peroxide, associated with an increase in the activities of oxalate oxidase and peroxidase in the roots of wheat seedlings. The most advantageous and most rapidly induced pathway of hydrogen peroxide formation was the oxidation of oxalic acid by oxalate oxidase because in this case, a 10-min treatment of the roots with the lectins at 10 µg ml-1 was sufficient. The data from this study attest that the Azospirillum lectins can act as inducers of adaptation processes in the roots of wheat seedlings.

Avaliação da estabilidade do marcador plasmático do estresse oxidativo: malondialdeído Evaluation of the stability of the oxidative stress plasmatic biomarker: malondialdehyde

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Denise Grotto

2008-01-01

Full Text Available Malondialdehyde (MDA is one of the lipid peroxidation products widely used as indicator of cellular injury. However, the short-term and the long-term stability of this biomarker remain unclear. The objective of this work was to evaluate the stability of plasmatic MDA at -20 ºC, utilizing thiobarbituric acid (TBA as derivative in spectrophotometric and chromatographic analysis. The results showed that MDA was stable for 24 h after blood collection, was not stable when stored after alkaline hydrolysis, remained stable for 30 days after TBA derivatization and was stable for 3 days when stored after n-butanol extraction, all at -20 ºC.

Radioprotective property of the ethanolic extract of Piper betel leaf

International Nuclear Information System (INIS)

Bhattacharya, S.; Roychowdhury, S.; Bandyopadhyay, S.K.; Subramanian, M.; Bauri, A.K.; Chattopadhyay, S.; Kamat, J.P.

2005-01-01

The radioprotective activity of Piper betel ethanolic extract (PE) has been studied using rat liver mitochondria and pBR 322 plasmid DNA as two model in vitro systems. The extract effectively prevented γ-ray induced lipid peroxidation as assessed by measuring thiobarbituric acid reactive substrates, lipid hydroperoxide and conjugated diene. Likewise, it prevented radiation-induced DNA strand breaks in a concentration dependent manner. The radioprotective activity of PE could be attributed to its hydroxyl and superoxide radicals scavenging property along with its lymphoproliferative activity. The radical scavenging capacity of PE was primarily due to its constituent phenolics, which were isolated and identified as chevibetol and allyl pyrocatechol. (author)

Radiation induced lipid oxidation in fish

International Nuclear Information System (INIS)

Snauwaert, F.; Tobback, P.; Maes, E.; Thyssen, J.

1977-01-01

Oxidative rancidity in herring and redfish was studied as a function of the applied irradiation dose, the storage time and storage temperature and the packaging conditions. - Measurements of the TBA (thiobarbituric acid) value and the peroxide value were used to evaluate the degree of oxidation of lipids, and were related with sensory scores. - Especially for the fatty fish species (herring) irradiation accelerated lipid oxidation and induced oxidative rancidity. Irradiation of vacuum-packed herring fillets and subsequent storage at +2 C seems to be an interesting process. For the experiments conducted on a semi-fatty fish (redfish), oxidative rancidity was never the limiting factor for organoleptic acceptability. (orig.) [de

Hydrogen peroxide stabilization in one-dimensional flow columns

Science.gov (United States)

Schmidt, Jeremy T.; Ahmad, Mushtaque; Teel, Amy L.; Watts, Richard J.

2011-09-01

Rapid hydrogen peroxide decomposition is the primary limitation of catalyzed H 2O 2 propagations in situ chemical oxidation (CHP ISCO) remediation of the subsurface. Two stabilizers of hydrogen peroxide, citrate and phytate, were investigated for their effectiveness in one-dimensional columns of iron oxide-coated and manganese oxide-coated sand. Hydrogen peroxide (5%) with and without 25 mM citrate or phytate was applied to the columns and samples were collected at 8 ports spaced 13 cm apart. Citrate was not an effective stabilizer for hydrogen peroxide in iron-coated sand; however, phytate was highly effective, increasing hydrogen peroxide residuals two orders of magnitude over unstabilized hydrogen peroxide. Both citrate and phytate were effective stabilizers for manganese-coated sand, increasing hydrogen peroxide residuals by four-fold over unstabilized hydrogen peroxide. Phytate and citrate did not degrade and were not retarded in the sand columns; furthermore, the addition of the stabilizers increased column flow rates relative to unstabilized columns. These results demonstrate that citrate and phytate are effective stabilizers of hydrogen peroxide under the dynamic conditions of one-dimensional columns, and suggest that citrate and phytate can be added to hydrogen peroxide before injection to the subsurface as an effective means for increasing the radius of influence of CHP ISCO.

Effect of gamma irradiation on the microbial load, chemical and sensory properties of the goat meat

International Nuclear Information System (INIS)

Al-Bachir, M.; Zeinou, R.

2010-07-01

The present study was undertaken to assess the quality characteristics and to evaluate the effects of gamma irradiation (0, 2, 4, and 6 kGy) of Jabaly Syrian goat meat on microbiological, chemical, and sensory characteristics during storage at 4 degree centigrade (1, 3, 4, and 5 weeks). Irradiation was effective in reducing the microbial load and increasing the shelf-life of goat meat. The radiation doses required to reduce the microorganisms by 90 percent (D10) in goat meat were 294 and 400 Gy for the Salmonella and E. coli, respectively. The main fatty acids identified from the goat meat were oleic, stearic, and palmitic acids. No significant differences were observed in moisture, crud protein, crud fat, ash, pH value, fatty acids, total acidity, volatile basic nitrogen, and sensory properties (texture, flavor, color, and taste) of the radiation processing and non-irradiated goat meat. Lipid peroxidation measured in term of thiobarbituric acid-reactive substances (TBARS) on irradiation and chilled storage increased. (Author)

Preparation of fulvic acid and low-molecular organic acids by oxidation of weathered coal humic acid

Energy Technology Data Exchange (ETDEWEB)

Shinozuka, T.; Ito, A.; Sasaki, O.; Yazawa, Y.; Yamaguchi, T. [Chiba Institute of Technolgy, Chiba (Japan). Dept. of Industrial Chemistry

2002-07-01

Weathered coal contains much humic acid and a little fulvic acid. Therefore, the production of fulvic acid, the most valuable humic substance because of its water-solubility, was examined by ozone and hydrogen peroxide oxidation of humic acid extracted form Xinjiang (China) weathered coal. The resulting products of the oxidation were water soluble fulvic acid and organic acids, mainly formic acid and oxalic acid. The product yield of fulvic acid was 20 (C%) and that of organic acids were 39 (C%) for formic and acid 13 (C%) for oxalic acid. The formed fulvic acid showed a higher content of oxygen and carboxyl groups, than those of the extracted one from the original weathered coal.

Photoproduction of hydrogen peroxide in aqueous solution from model compounds for chromophoric dissolved organic matter (CDOM)

International Nuclear Information System (INIS)

Clark, Catherine D.; Bruyn, Warren de; Jones, Joshua G.

2014-01-01

Highlights: • CDOM produces hydrogen peroxide in sunlit surface waters. • Quinone moieties have been proposed as the photo-active chromophore in CDOM. • Hydrogen peroxide is produced in irradiated aqueous quinone solutions. • Concentrations and production rates are comparable to humic and fulvic acids. • Optical properties post-irradiation were similar to CDOM. - Abstract: To explore whether quinone moieties are important in chromophoric dissolved organic matter (CDOM) photochemistry in natural waters, hydrogen peroxide (H 2 O 2 ) production and associated optical property changes were measured in aqueous solutions irradiated with a Xenon lamp for CDOM model compounds (dihydroquinone, benzoquinone, anthraquinone, napthoquinone, ubiquinone, humic acid HA, fulvic acid FA). All compounds produced H 2 O 2 with concentrations ranging from 15 to 500 μM. Production rates were higher for HA vs. FA (1.32 vs. 0.176 mM h −1 ); values ranged from 6.99 to 0.137 mM h −1 for quinones. Apparent quantum yields (Θ app ; measure of photochemical production efficiency) were higher for HA vs. FA (0.113 vs. 0.016) and ranged from 0.0018 to 0.083 for quinones. Dihydroquinone, the reduced form of benzoquinone, had a higher production rate and efficiency than its oxidized form. Post-irradiation, quinone compounds had absorption spectra similar to HA and FA and 3D-excitation–emission matrix fluorescence spectra (EEMs) with fluorescent peaks in regions associated with CDOM

Modifications of proteins by polyunsaturated fatty acid peroxidation products

DEFF Research Database (Denmark)

Refsgaard, Hanne; Tsai, Lin; Stadtman, Earl

2000-01-01

The ability of unsaturated fatty acid methyl esters to modify amino acid residues in bovine serum albumin (BSA), glutamine synthetase, and insulin in the presence of a metal-catalyzed oxidation system [ascorbate/Fe(lll)/O-2] depends on the degree of unsaturation of the fatty acid. The fatty acid......-dependent generation of carbonyl groups and loss of lysine residues increased in the order methyl linoleate fatty acids were oxidized in the presence...... in the formation of protein carbonyls, These results are consistent with the proposition that metal-catalyzed oxidation of polyunsaturated fatty acids can contribute to the generation of protein carbonyls by direct interaction of lipid oxidation products (alpha,beta-unsaturated aldehydes) with lysine residues...

Rearrangements of organic peroxides and related processes

Directory of Open Access Journals (Sweden)

Ivan A. Yaremenko

2016-08-01

Full Text Available This review is the first to collate and summarize main data on named and unnamed rearrangement reactions of peroxides. It should be noted, that in the chemistry of peroxides two types of processes are considered under the term rearrangements. These are conventional rearrangements occurring with the retention of the molecular weight and transformations of one of the peroxide moieties after O–O-bond cleavage. Detailed information about the Baeyer−Villiger, Criegee, Hock, Kornblum−DeLaMare, Dakin, Elbs, Schenck, Smith, Wieland, and Story reactions is given. Unnamed rearrangements of organic peroxides and related processes are also analyzed. The rearrangements and related processes of important natural and synthetic peroxides are discussed separately.

Protein oxidation and peroxidation

DEFF Research Database (Denmark)

Davies, Michael Jonathan

2016-01-01

Proteins are major targets for radicals and two-electron oxidants in biological systems due to their abundance and high rate constants for reaction. With highly reactive radicals damage occurs at multiple side-chain and backbone sites. Less reactive species show greater selectivity with regard...... to the residues targeted and their spatial location. Modification can result in increased side-chain hydrophilicity, side-chain and backbone fragmentation, aggregation via covalent cross-linking or hydrophobic interactions, protein unfolding and altered conformation, altered interactions with biological partners...... and modified turnover. In the presence of O2, high yields of peroxyl radicals and peroxides (protein peroxidation) are formed; the latter account for up to 70% of the initial oxidant flux. Protein peroxides can oxidize both proteins and other targets. One-electron reduction results in additional radicals...

Kraft pulp bleaching with molybdenum activated acid peroxide (PMo stage)

International Nuclear Information System (INIS)

Rabelo, Marcos Sousa

2009-01-01

Optimum conditions to run the P Mo stage for bleaching eucalyptus kraft pulp were 90 deg C, pH 3.5, 2 h, 0.1 kg/t Mo and 5 kg/t H 2 O 2 . The P Mo stage efficiency increased with decreasing pH (1.5-5.5) and increasing temperature (75-90 deg C), time (2-4 h), and hydrogen peroxide (3-10 kg/t) and molybdenum concentration (0.1-0.4 kg/t). The implementation of the P Mo stage, as replacement for the A stage, decreased total active chlorine demand of the OAZDP sequence by 6 kg/t to reach 90% ISO, both in laboratory and mill scale. Such practice resulted in decreased bleaching chemical costs to produce fully bleached pulp of 90% ISO. (author)

Spectroscopic studies on the antioxidant activity of ellagic acid

Science.gov (United States)

Kilic, Ismail; Yeşiloğlu, Yeşim; Bayrak, Yüksel

2014-09-01

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

Characterization of lipid oxidation process of beef during repeated freeze-thaw by electron spin resonance technology and Raman spectroscopy.

Science.gov (United States)

Chen, Qingmin; Xie, Yunfei; Xi, Jinzhong; Guo, Yahui; Qian, He; Cheng, Yuliang; Chen, Yi; Yao, Weirong

2018-03-15

In this study, electron spin resonance (ESR) and Raman spectroscopy were applied to characterize lipid oxidation of beef during repeated freeze-thaw (RFT). Besides the conventional indexes including peroxide values (PV), thiobarbituric acid-reactive substances (TBARS) and acid values (AV) were evaluated, the radical and molecular structure changes were also measured by ESR and Raman spectroscopy. The results showed that PV, TBARS and AV were increased (PRaman intensity of ν(CC) stretching region (1655cm -1 ) was decreased during RFT. Furthermore, lower Raman intensity ratio of I 1655 /I 1442 , I 1655 /I 1745 that determine total unsaturation was also observed. Significant correlations (pRaman spectroscopy. Our result has proved that ESR and Raman spectroscopy showed great potential in characterizing lipid oxidation process of beef during RFT. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Influence of Chemical Surface Modification of Kenaf Fiber using Hydrogen Peroxide on the Mechanical Properties of Biodegradable Kenaf Fiber/Poly(Lactic Acid Composites

Directory of Open Access Journals (Sweden)

Nur Inani Abdul Razak

2014-03-01

Full Text Available Bleaching treatment of kenaf fiber was performed in alkaline medium containing hydrogen peroxide solution maintained at pH 11 and 80 °C for 60 min. The bleached kenaf fiber was analyzed using Fourier Transform Infrared (FTIR and X-ray Diffraction (XRD analysis. The bleached kenaf fiber was then compounded with poly-(lactic acid (PLA via a melt blending method. The mechanical (tensile, flexural and impact performance of the product was tested. The fiber treatment improved the mechanical properties of PLA/bleached kenaf fiber composites. Scanning electron micrograph (SEM morphological analysis showed improvement of the interfacial adhesion between the fiber surface and polymer matrix.

Hydrophosphorylation of alkynes with phosphinous acids

International Nuclear Information System (INIS)

Nifant'ev, E.E.; Solovetskaya, L.A.; Magdeeva, R.K.

1986-01-01

A feature of the homolytic hydrophosphorylation of alkynes, as compared with alkenes, is more ready addition of phosphinous acids in presence of benzoyl peroxides. A difference was found in the hydrophosphorylation of acetylenes with dibutylphosphinous acid and with diarylphosphinous acids: the latter tend to form diaddition products

Inhibition of rat liver microsomal lipid peroxidation by N-acyldehydroalanines: An in vitro comparative study

Energy Technology Data Exchange (ETDEWEB)

Buc-Calderon, P.; Roberfroid, M. (Universite Catholique de Louvain, Brussels (Belgium))

1989-09-01

Captodative substituted olefins are radical scavengers which react with free radicals to form stabilized radical adducts. One of those compounds, N-(paramethoxyphenylacetyl)dehydroalanine (AD-5), may react and scavenge both superoxide anion (O-2) and alk-oxyl radicals (RO.), and in this way prevent the appearance of their mediated biological effects. Nitrofurantoin and tert-butyl hydroperoxide were used as model compounds to stimulate free radical production and their mediated lipid peroxidation in rat liver microsomes. In addition, lipid peroxidation was also initiated by exposure of rat liver microsomal suspensions to ionizing radiation (gamma rays). The microsomal lipid peroxidation induced by these chemicals and physical agents was inhibited by the addition of AD-5. These effects were dose-dependent in a millimolar range of concentration. In addition, AD-5 has no effect on microsomal electron transport, showing that NADPH-cytochrome P450 reductase activity was not modified. These data, together with the comparisons of the effects of AD-5 and some antioxidant molecules such as superoxide dismutase, uric acid, and mannitol, support the conclusion that inhibition of lipid peroxidation by AD-5 is the result of its free radical scavenger activity. In addition, the inhibitory effect of AD-5 on microsomal lipid peroxidation was dependent of the nature of the free radical species involved in the initiation of the process, suggesting that O-2 is scavenged more efficiently than RO.

Neuroprotective Effects of α-Tocotrienol on Kainic Acid-Induced Neurotoxicity in Organotypic Hippocampal Slice Cultures

Directory of Open Access Journals (Sweden)

Bae Hwan Lee

2013-09-01

Full Text Available Vitamin E, such as alpha-tocopherol (ATPH and alpha-tocotrienol (ATTN, is a chain-breaking antioxidant that prevents the chain propagation step during lipid peroxidation. In the present study, we investigated the effects of ATTN on KA-induced neuronal death using organotypic hippocampal slice culture (OHSC and compared the neuroprotective effects of ATTN and ATPH. After 15 h KA (5 µM treatment, delayed neuronal death was detected in the CA3 region and reactive oxygen species (ROS formation and lipid peroxidation were also increased. Both co-treatment and post-treatment of ATPH (100 µM or ATTN (100 µM significantly increased the cell survival and reduced the number of TUNEL-positive cells in the CA3 region. Increased dichlorofluorescein (DCF fluorescence and levels of thiobarbiturate reactive substances (TBARS were decreased by ATPH and ATTN treatment. These data suggest that ATPH and ATTN treatment have protective effects on KA-induced cell death in OHSC. ATTN treatment tended to be more effective than ATPH treatment, even though there was no significant difference between ATPH and ATTN in co-treatment or post-treatment.

Exercise performance, red blood cell deformability, and lipid peroxidation: effects of fish oil and vitamin E

NARCIS (Netherlands)

Oostenbrug, G. S.; Mensink, R. P.; Hardeman, M. R.; de Vries, T.; Brouns, F.; Hornstra, G.

1997-01-01

Previous studies have indicated that fish oil supplementation increases red blood cell (RBC) deformability, which may improve exercise performance. Exercise alone, or in combination with an increase in fatty acid unsaturation, however, may enhance lipid peroxidation. Effects of a bicycle time trial

Kinetics of Platinum-Catalyzed Decomposition of Hydrogen Peroxide

Science.gov (United States)

Vetter, Tiffany A.; Colombo, D. Philip, Jr.

2003-07-01

CIBA Vision Corporation markets a contact lens cleaning system that consists of an AOSEPT disinfectant solution and an AOSEPT lens cup. The disinfectant is a buffered 3.0% m/v hydrogen peroxide solution and the cup includes a platinum-coated AOSEPT disc. The hydrogen peroxide disinfects by killing bacteria, fungi, and viruses found on the contact lenses. Because the concentration of hydrogen peroxide needed to disinfect is irritating to eyes, the hydrogen peroxide needs to be neutralized, or decomposed, before the contact lenses can be used again. A general chemistry experiment is described where the kinetics of the catalyzed decomposition of the hydrogen peroxide are studied by measuring the amount of oxygen generated as a function of time. The order of the reaction with respect to the hydrogen peroxide, the rate constant, and the energy of activation are determined. The integrated rate law is used to determine the time required to decompose the hydrogen peroxide to a concentration that is safe for eyes.

Salicylic acid induces apoptosis in colon carcinoma cells grown in-vitro: Influence of oxygen and salicylic acid concentration

International Nuclear Information System (INIS)

Zitta, Karina; Meybohm, Patrick; Bein, Berthold; Huang, Ying; Heinrich, Christin; Scholz, Jens; Steinfath, Markus; Albrecht, Martin

2012-01-01

In solid tumors the hypoxic environment can promote tumor progression and resistance to therapy. Recently, acetylsalicylic acid a major component of analgesic drugs and its metabolite salicylic acid (SA) have been shown to reduce the risk of colon cancer, but the mechanisms of action remain still unclear. Here we elucidate the effects of physiologically relevant concentrations of SA on colon carcinoma cells (CaCo-2) grown under normoxic and hypoxic conditions. Western blotting, caspase-3/7 apoptosis assays, MTS cell-proliferation assays, LDH cytotoxicity assays and hydrogen peroxide measurements were performed to investigate the effects of 1 and 10 μM SA on CaCo-2 cells grown under normoxic conditions and cells exposed to hypoxia. Under normoxic conditions, SA did not influence cell proliferation or LDH release of CaCo-2 cells. However, caspase-3/7 activity was significantly increased. Under hypoxia, cell proliferation was reduced and LDH release and caspase-3/7 activities were increased. None of these parameters was altered by the addition of SA under hypoxic conditions. Hypoxia increased hydrogen peroxide concentrations 300-fold and SA significantly augmented the release of hydrogen peroxide under normoxic, but not under hypoxic conditions. Phosphorylation of the pro-survival kinases akt and erk1/2 was not changed by SA under hypoxic conditions, whereas under normoxia SA reduced phosphorylation of erk1/2 after 2 hours. We conclude that in colon carcinoma cells effects of SA on apoptosis and cellular signaling are dependent on the availability of oxygen. -- Highlights: ► Effects of salicylic acid on colon carcinoma cells grown under normoxic and hypoxic conditions ► Salicylic acid increases caspase-3/7 activity and hydrogen peroxide release under normoxia ► Salicylic acid decreases pro-survival erk-1/2 phosphorylation under normoxia ► Salicylic acid does not influence any of the investigated parameters under hypoxia

Hydrogen Peroxide Probes Directed to Different Cellular Compartments

Science.gov (United States)

Malinouski, Mikalai; Zhou, You; Belousov, Vsevolod V.; Hatfield, Dolph L.; Gladyshev, Vadim N.

2011-01-01

Background Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells. Principal Findings Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events. Conclusions We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells. PMID:21283738

Hydrogen peroxide probes directed to different cellular compartments.

Directory of Open Access Journals (Sweden)

Mikalai Malinouski

2011-01-01

Full Text Available Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells.Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events.We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells.

Effect of natural antioxidants on the stability of ostrich meat during storage

Energy Technology Data Exchange (ETDEWEB)

Abou-Arab, E. A.; Abu-Salem, F. M.

2010-07-01

Meat from the ostrich is becoming increasingly popular throughout the world. The aim of the current study was to evaluate the effects of different antioxidants such as ascorbic acid (AA), {alpha}-tocopherol (Toc) and rosemary herb (Ros) on the stability of ostrich meat during storage. The chemical composition of ostrich meat showed low fat content (1.5 %) combined with high protein content (22.4 %). The combination of AA Ros, Toc Ros and AA Toc was more effective in reducing the thiobarbituric acid (TBA) and peroxide values. The antioxidant showed insignificant effects on acidity as oleic acid. The addition of the efficient role of AA, Toc and Ros showed an improvement in the color stability of ostrich steaks and the combined treatment was more effective in color stability. In conclusion, the addition of AA, Toc and Ros had a positive effect on aroma quality, rancidity and discoloration of refrigerated ostrich meat. (Author) 41 refs.

The principal phenolic and alcoholic components of wine protect human lymphocytes against hydrogen peroxide- and ionising radiation-induced DNA damage in vitro

International Nuclear Information System (INIS)

Fenech, M.; Greenrod, W.

2003-01-01

We have tested the hypothesis that the alcoholic and phenolic components of wine are protective against the DNA damaging and cytotoxic effects of hydrogen peroxide and gamma radiation in vitro. The components of wine tested were ethanol, glycerol, a mixture of the phenolic compounds catechin and caffeic acid, and tartaric acid, all at concentrations that were 2.5% or 10.0% of the concentration in a typical Australian white wine Riesling. These components were tested individually or combined as a mixture and compared to a white wine stripped of polyphenols as well as a Hanks balanced salt solution control which was the diluent for the wine components. The effect of the components was tested in lymphocytes, using the cytokinesis-block micronucleus assay, after 30 minutes incubation in plasma or whole blood for the hydrogen peroxide or gamma-radiation challenge respectively. The results obtained showed that ethanol, glycerol, the catechin-caffeic acid mixture, the mixture of all components, and the stripped white wine significantly reduced the DNA damaging effects of hydrogen peroxide and gamma radiation (ANOVA P = 0.043 - 0.001). The strongest protective effect against DNA damage by gamma irradiation was observed for the catechin-caffeic acid mixture and mixture of all components (30% and 32% reduction respectively). These two treatments as well as ethanol produced the strongest protective effects against DNA damage by hydrogen peroxide (24%, 25% and 18% respectively) . The protection provided by the mixture did not account for the expected additive protective effects of the individual components suggesting that the components may be exerting their effects through similar mechanisms which are saturated at the concentrations tested. Ethanol was the only component that significantly increased base-line DNA damage rate, however, this effect was negated in the mixture. In conclusion our results suggest that the main phenolic and alcoholic components of wine can reduce

Radappertization of ready-to-eat shelf-stable, traditional Indian bread - Methi Paratha

International Nuclear Information System (INIS)

Bhoir, Shraddha A.; Muppalla, Shobita R.; Kanatt, Sweetie R.; Chawla, S.P.; Sharma, Arun

2015-01-01

Shelf-stable ready-to-eat (RTE) Methi Paratha (flavored Indian unleavened flat bread) was developed using combination of hurdles including radiation processing. The Methi Paratha was prepared using dough containing wheat flour, dried fenugreek leaves and spices. The samples were vacuum packed in multi-layered pouches and irradiated at 25 kGy in frozen conditions. Samples were evaluated for microbiological counts, lipid peroxidation and sensory attributes during storage under ambient conditions. Samples were found to be devoid of any viable microorganism throughout the storage period of 180 days. The thiobarbituric acid reactive substances (TBARS) value which indicates lipid peroxidation of samples did not show any significant increase with time. The Methi Paratha was found to be acceptable by the evaluating panelists. - Highlights: • Shelf-stable ready-to-eat (RTE) Methi Paratha (flavored Indian unleavened flat bread) was developed. • A combination of hurdles irradiation, vacuum-packaging and natural antioxidants was used. • Methi Paratha was microbiologically safe and sensorialy acceptable for 180 days

Deep desulfurization of diesel via peroxide oxidation using phosphotungstic acid as phase transfer catalyst

Energy Technology Data Exchange (ETDEWEB)

Sachdeva, T.O.; Pant, K.K. [Department of Chemical Engineering, Indian Institute of Technology, Delhi, New Delhi, 110016 (India)

2010-09-15

High sulfur level in diesel fuel has been identified as a major contributor to air pollutant in term of sulfur dioxide (SO{sub x}) through diesel fueled vehicles. The main aim of the present work is to develop a promising methodology for ultra deep desulfurization of diesel fuel using oxidation followed by phase transfer of oxidized sulfur. Experiments were carried out in a batch reactor using n-decane as the model diesel compound and also using commercial diesel feedstock. To remove sulfur tetraoctylammonium bromide, phosphotungstic acid, and hydrogen peroxide were used as phase transfer agent, catalyst and oxidant respectively. The percent sulfur removal increases with increasing the initial concentration of sulfur in fuel and with increasing the reaction temperature. Similar trends were observed when commercial diesel was used to carry out desulfurization studies. The amphiphilic catalyst serves as a catalyst and also as an emulsifying agent to stabilize the emulsion droplets. The effects of temperature, agitation speed, quantity of catalyst and the phase transfer agent were studied to estimate the optimal conditions for the reactions. The sulfur removal from a commercial diesel by phase transfer catalysis has been found effective and removal efficiency was more than 98%. Kinetic experiments carried out for the desulfurization revealed that the sulfur removal results are best fitted to a pseudo first order kinetics and the apparent activation energy of desulfurization was 30.6 kJ/mol. (author)

Deep desulfurization of diesel via peroxide oxidation using phosphotungstic acid as phase transfer catalyst

International Nuclear Information System (INIS)

Sachdeva, T.O.; Pant, K.K.

2010-01-01

High sulfur level in diesel fuel has been identified as a major contributor to air pollutant in term of sulfur dioxide (SO x ) through diesel fueled vehicles. The main aim of the present work is to develop a promising methodology for ultra deep desulfurization of diesel fuel using oxidation followed by phase transfer of oxidized sulfur. Experiments were carried out in a batch reactor using n-decane as the model diesel compound and also using commercial diesel feedstock. To remove sulfur tetraoctylammonium bromide, phosphotungstic acid, and hydrogen peroxide were used as phase transfer agent, catalyst and oxidant respectively. The percent sulfur removal increases with increasing the initial concentration of sulfur in fuel and with increasing the reaction temperature. Similar trends were observed when commercial diesel was used to carry out desulfurization studies. The amphiphilic catalyst serves as a catalyst and also as an emulsifying agent to stabilize the emulsion droplets. The effects of temperature, agitation speed, quantity of catalyst and the phase transfer agent were studied to estimate the optimal conditions for the reactions. The sulfur removal from a commercial diesel by phase transfer catalysis has been found effective and removal efficiency was more than 98%. Kinetic experiments carried out for the desulfurization revealed that the sulfur removal results are best fitted to a pseudo first order kinetics and the apparent activation energy of desulfurization was 30.6 kJ/mol. (author)

Improvement of the Quality and the Shelf Life of the High Oxygen Modified Atmosphere Packaged Veal by Superficial Spraying with Dihydroquercetin Solution

Directory of Open Access Journals (Sweden)

Stefan Georgiev Dragoev

2014-01-01

Full Text Available The improvement of quality and the shelf life of veal by combination of 80%O2/20%CO2 modified atmosphere packaging and superficial spraying with 0.02% dihydroquercetin solutions was studied. The control samples C, air packaged only, D, air packaged sprayed by 0.02% dihydroquercetin solution, MAP, modified atmosphere packaging only, BMAP, modified atmosphere packaging sprayed by 0.02% butylated hydroxytoluene solution, and DMAP, modified atmosphere packaging sprayed by 0.02% dihydroquercetin solution, were measured. The best results were obtained in modified atmosphere packaging sprayed by 0.02% dihydroquercetin solution. Comparisons with control samples were expressed as reduction in acid value with 27.72%, peroxide value with 64.74%, 2-thiobarbituric acid reactive substances (TBARS with 65.71%, and the pH with 6.18%. The acid and peroxide values, TBARS, and pH were decreased linearly in response when applying the combination of 80%O2/20%CO2 modified atmosphere packaging and superficial spraying with 0.02% dihydroquercetin solutions (P0.05. According to results obtained it was concluded that 80%O2/20%CO2 modified atmosphere packaged veal stored at 0±0.5°C after 0.02% dihydroquercetin solution treatment can preserve its quality and shelf life to 15 d postmortem.

Hydrogen peroxide treatment of TCE contaminated soil

International Nuclear Information System (INIS)

Hurst, D.H.; Robinson, K.G.; Siegrist, R.L.

1993-01-01

Solvent contaminated soils are ubiquitous in the industrial world and represent a significant environmental hazard due to their persistence and potentially negative impacts on human health and the environment. Environmental regulations favor treatment of soils with options which reduce the volume and toxicity of contaminants in place. One such treatment option is the in-situ application of hydrogen peroxide to soils contaminated with chlorinated solvents such as trichloroethylene (TCE). This study investigated hydrogen peroxide mass loading rates on removal of TCE from soils of varying organic matter content. Batch experiments conducted on contaminated loam samples using GC headspace analysis showed up to 80% TCE removal upon peroxide treatment. Column experiments conducted on sandy loam soils with high organic matter content showed only 25% TCE removal, even at hydrogen peroxide additions of 25 g peroxide per kg soil

The effects of dietary boric acid and borax supplementation on lipid peroxidation, antioxidant activity, and DNA damage in rats.

Science.gov (United States)

Ince, Sinan; Kucukkurt, Ismail; Cigerci, Ibrahim Hakki; Fatih Fidan, A; Eryavuz, Abdullah

2010-07-01

The aims of this study were to clarify the effects of high dietary supplementation with boric acid and borax, called boron (B) compounds, on lipid peroxidation (LPO), antioxidant activity, some vitamin levels, and DNA damage in rats. Thirty Sprague Dawley male rats were divided into three equal groups: the animals in the first group (control) were fed with a standard rodent diet containing 6.4 mg B/kg, and the animals in the experimental group were fed with a standard rodent diet added with a supra-nutritional amount of boric acid and borax (100 mg B/kg) throughout the experimental period of 28 days. The B compounds decreased malondialdehyde (MDA), DNA damage, the protein carbonyl content (PCO) level in blood, and glutathione (GSH) concentration in the liver, Cu-Zn superoxide dismutase (SOD), and catalase (CAT) activity in the kidney. The B compounds increased GSH concentration in blood and the vitamin C level in plasma. Consequently, our results demonstrate that B supplementation (100 mg/kg) in diet decreases LPO, and enhances the antioxidant defense mechanism and vitamin status. There are no differences in oxidant/antioxidant balance and biochemical parameters except for serum vitamin A and liver GSH concentration, between the boron compounds used in this study. Crown Copyright 2010. Published by Elsevier GmbH. All rights reserved.

The Effectiveness of Rambutan (Nephelium lappaceum L.) Extract in Stabilization of Sunflower Oil under Accelerated Conditions

Science.gov (United States)

Mei, Winne Sia Chiaw; Ismail, Amin; Mohd. Esa, Norhaizan; Akowuah, Gabriel Akyirem; Wai, Ho Chun; Seng, Yim Hip

2014-01-01

The oxidative properties of sunflower oil supplemented with rambutan extract, (crude extract and its fractionated fraction, SF II) in comparison with synthetic antioxidant were investigated. The supplemented sunflower oils were stored under accelerated conditions for 24 days at 60 °C. For every 6-day interval, the oxidative properties of the supplemented sunflower oil were evaluated based on the following tests, namely peroxide value, p-anisidine value, Thiobarbituric Acid Reactive Substances (TBARS) assay, iodine value and free fatty acids. The total oxidation (TOTOX) values were also calculated based on the peroxide values and p-anisidine values. Rambutan extract is a potential source of antioxidant. The oxidative activities of the extracts at all concentrations were significantly (p crude extract. With a 2-year storage period at ambient temperature, the fractionated fraction of the extract, SF II at 300 ppm, was observed to work more effectively than the synthetic antioxidant, t-Tocopherol, and it possessed a protective effect comparable with butylatedhydrioxynanisole (BHA). Therefore, rambutan extract could be used as a potential alternative source of antioxidant in the oil industry or other fat-based products to delay lipid oxidation. PMID:26784877

N-Acetyl-L-Cysteine Affords Protection against Lead-Induced Cytotoxicity and Oxidative Stress in Human Liver Carcinoma (HepG2 Cells

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Paul B. Tchounwou

2007-06-01

Full Text Available Although lead exposure has declined in recent years as a result of change to lead-free gasoline, several epidemiological have pointed out that it represents a medical and public health emergency, especially in young children consuming high amounts of lead-contaminated flake paints. A previous study in our laboratory indicated that lead exposure induces cytotoxicity in human liver carcinoma cells. In the present study, we evaluated the role of oxidative stress in lead-induced toxicity, and the protective effect of the anti-oxidant n-acetyl-l-cysteine (NAC. We hypothesized that oxidative stress plays a role in lead-induced cytotoxicity, and that NAC affords protection against this adverse effect. To test this hypothesis, we performed the MTT [3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide] assay and the trypan blue exclusion test for cell viability. We also performed the thiobarbituric acid test for lipid peroxidation. Data obtained from the MTT assay indicated that NAC significantly increased the viability of HepG2 cells in a dosedependent manner upon 48 hours of exposure. Similar trend was obtained with the trypan blue exclusion test. Data generated from the thiobarbituric acid test showed a significant (p ≤ 0.05 increase of MDA levels in lead nitrate-treated HepG2 cells compared to control cells. Interestingly, the addition of NAC to lead nitrate-treated HepG2 cells significantly decreased cellular content of reactive oxygen species (ROS, as evidenced by the decrease in lipid peroxidation byproducts. Overall, findings from this study suggest that NAC inhibits lead nitrate-induced cytotoxicity and oxidative stress in HepG2 cells. Hence, NAC may be used as a salvage therapy for lead-induced toxicity in exposed persons.

The Protective Effect of Hippophae Rhamnoides Carotenoid Extract Against Lipid Peroxidation in Crude Vegetable Oils

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Sanda Andrei

2014-11-01

Full Text Available Vegetable oils are important elements of the human diet because they contain essential nutritional factors. Due to the manufacturing processes or inadequate conditions of storage, they may also contain lipid oxidation products that are toxic to the body. The purpose of this paper is to test the protective effect of carotenoid-rich extracts obtained from the fruits of Hippophae rhamnoides on crude sunflower, pumpkin and olive oils oxidative processes. In order to evaluate the effect of antioxidant carotenoids, three stages were followed: thermal induction of lipid peroxidation in the presence of AAPH (2,2'-Azobis(2-amidinopropane dihydrochloride; determination of the level of lipid peroxidation in oxidized oils in the presence and absence of antioxidants, by quantifying the concentration of conjugated dienes and malonyl dialdehyde (MDA; determination of the level of lipid peroxidation by evaluating the profile of the fatty acids and the ratio between the saturated and unsaturated fatty acids (UFA / SFA, using an GC-MS method. In the case of sunflower oil, it was observed that sea buckthorn fruit extract significantly decreased MDA concentration but does not significantly reduce the concentration of conjugated dienes. The protective effect of carotenoids is more evident in the case of oil from pumpkin seeds. In the olive oil, unlike the first two types of oils, the carotenoids extract inhibits both the MDA and the conjugated dienes formation to a lesser extent, statistically insignificant. Overall, the ratio UFA / SFA decreases in crude oxidized oils. In the oils in which carotenoids were added was observed an increase in the UFA / SFA ratio. Carotenoids fraction from sea buckthorn fruits, rich in xanthophylls’ esters, possess a good antioxidant effect, protecting vegetable oils against peroxidation processes induced in the presence of AAPH

Antioxidative Defense Responses to lead-induced Oxidative Stress in Glycine max L. CV. Merrill grown in Different pH Gradient

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Mishra, Pankaj Kishor

2013-04-01

Full Text Available Physiological and biochemical changes as well as the activities of anti-oxidative enzymes under lead (Pb2+ phytotoxicity were investigated in 20 days old soybean (Glycine max L. seedlings grown hydroponically in the laboratory under different pH conditions. The rapid uptake of Pb 2+ was observed immediately after the start of treatment. The quantity of accumulation of Pb2+ was much higher in roots than in shoots, its level rising with increasing pH from 3.0 to 8.0 . Not only that, an oxidative stress conditions were observed due to increased level of superoxide anion radical and hydrogen peroxide in shoots and root cells of 20 days old seedlings when treated with Pb(NO32 at a concentration of 0, 500, 1000 and 2000 μM. Spectrometric assays of seedlings showed increased level of activities of antioxidant enzymes like catalase, peroxidase and glutathione reductase. The presence of thiobarbituric acid reacting substances (TBARS indicates the enhanced lipid peroxidation compared to controls. The alteration in the activities of the antioxidant enzymes and the induction of lipid peroxidation reflects the presence of Pb2+, which may cause oxidative stress.

Relation between serum lipoperoxide concentrations and iron or copper status over one year in Cuban adult men

Energy Technology Data Exchange (ETDEWEB)

Arnaud, J.; Renversez, J.C.; Favier, A.E. [Dept. de Biologie Integree, CHUG, Grenoble (France); Fleites, P.; Perez-Cristia, R. [Centro national de Toxicologia (CENATOX), La Habana (Cuba); Chassagne, M.; Barnouin, J. [INRA, Unite d' Ecopathologie, Saint Genes Champanelle (France); Verdura, T. [Inst. Finlay, La Lisa, La Habana (Cuba); Garcia, I.G. [Inst. de Farmacia y Alimentos, La Coronela, La Lisa, Ciudad de la Habana (Cuba); Tressol, J.C. [INRA, Unite maladies metaboliques et micronutriments, Saint Genes Champanelle (France)

2001-07-01

The aims of this study were to determine the relations between iron and copper status and lipid peroxidation at different periods over one year in low-income and low-energy intake healthy subjects. The study was conducted in 199 middle-aged healthy Cuban men from March 1995 to February 1996. Iron status was assessed by the determination of serum ferritin, transferrin saturation, whole blood hemoglobin and iron intakes. Copper status was evaluated by the determination of serum copper and copper intakes. Serum thiobarbituric acid substances (TBARS) determination was used as an index of lipid peroxidation. Rank correlations were observed between serum TBARS concentrations and iron or copper status indices at different periods. In period 3 (end of the rainy season), serum TBARS and ferritin concentrations were maximum whereas blood hemoglobin levels and iron intake were minimum. Serum TBARS concentrations were significantly higher than the reference values of the laboratory whereas, iron and copper status were within the reference ranges. These results suggested that iron and copper status may be associated with lipid peroxidation in subjects without metal overloads and that variations over the year needed to be taken in account. (orig.)

Determination of hydrogen peroxide in water by chemiluminescence detection, (1). Flow injection type hydrogen peroxide detection system

International Nuclear Information System (INIS)

Yamashiro, Naoya; Uchida, Shunsuke; Satoh, Yoshiyuki; Morishima, Yusuke; Yokoyama, Hiroaki; Satoh, Tomonori; Sugama, Junichi; Yamada, Rie

2004-01-01

A flow injection type hydrogen peroxide detection system with a sub-ppb detection limit has been developed to determine hydrogen peroxide concentration in water sampled from a high temperature, high pressure hydrogen peroxide water loop. The hydrogen peroxide detector is based on luminol chemiluminescence spectroscopy. A small amount of sample water (20 μl) is mixed with a reagent mixture, an aqueous solution of luminol and Co 2+ catalyst, in a mixing cell which is installed just upstream from the detection cell. The optimum values for pH and the concentrations of luminol and Co 2+ ion have been determined to ensure a lower detectable limit and a higher reproducibility. The photocurrent detected by the detection system is expressed by a linear function of the hydrogen peroxide concentration in the region of lower concentration ([H 2 O 2 ] 2 O 2 ] in the region of higher concentration ([H 2 O 2 ] > 10 ppb). The luminous intensity of luminol chemiluminescence is the highest when pH of the reagent mixture is 11.0. Optimization of the major parameters gives the lowest detectable limit of 0.3 ppb. (author)

Respiratory Symptoms in Hospital Cleaning Staff Exposed to a Product Containing Hydrogen Peroxide, Peracetic Acid, and Acetic Acid.

Science.gov (United States)

Hawley, Brie; Casey, Megan; Virji, Mohammed Abbas; Cummings, Kristin J; Johnson, Alyson; Cox-Ganser, Jean

2017-12-15

Cleaning and disinfecting products consisting of a mixture of hydrogen peroxide (HP), peracetic acid (PAA), and acetic acid (AA) are widely used as sporicidal agents in health care, childcare, agricultural, food service, and food production industries. HP and PAA are strong oxidants and their mixture is a recognized asthmagen. However, few exposure assessment studies to date have measured HP, PAA, and AA in a health care setting. In 2015, we performed a health and exposure assessment at a hospital where a new sporicidal product, consisting of HP, PAA, and AA was introduced 16 months prior. We collected 49 full-shift time-weighted average (TWA) air samples and analyzed samples for HP, AA, and PAA content. Study participants were observed while they performed cleaning duties, and duration and frequency of cleaning product use was recorded. Acute upper airway, eye, and lower airway symptoms were recorded in a post-shift survey (n = 50). A subset of 35 cleaning staff also completed an extended questionnaire that assessed symptoms reported by workers as regularly occurring or as having occurred in the previous 12 months. Air samples for HP (range: 5.5 to 511.4 ppb) and AA (range: 6.7 to 530.3 ppb) were all below established US occupational exposure limits (OEL). To date, no full-shift TWA OEL for PAA has been established in the United States, however an OEL of 0.2 ppm has been suggested by several research groups. Air samples for PAA ranged from 1.1 to 48.0 ppb and were well below the suggested OEL of 0.2 ppm. Hospital cleaning staff using a sporicidal product containing HP, PAA, and AA reported work-shift eye (44%), upper airway (58%), and lower airway (34%) symptoms. Acute nasal and eye irritation were significantly positively associated with increased exposure to the mixture of the two oxidants: HP and PAA, as well as the total mixture (TM)of HP, PAA, and AA. Shortness of breath when hurrying on level ground or walking up a slight hill was significantly associated

Respiratory Symptoms in Hospital Cleaning Staff Exposed to a Product Containing Hydrogen Peroxide, Peracetic Acid, and Acetic Acid

Science.gov (United States)

Hawley, Brie; Casey, Megan; Virji, Mohammed Abbas; Cummings, Kristin J.; Johnson, Alyson; Cox-Ganser, Jean

2017-01-01

Cleaning and disinfecting products consisting of a mixture of hydrogen peroxide (HP), peracetic acid (PAA), and acetic acid (AA) are widely used as sporicidal agents in health care, childcare, agricultural, food service, and food production industries. HP and PAA are strong oxidants and their mixture is a recognized asthmagen. However, few exposure assessment studies to date have measured HP, PAA, and AA in a health care setting. In 2015, we performed a health and exposure assessment at a hospital where a new sporicidal product, consisting of HP, PAA, and AA was introduced 16 months prior. We collected 49 full-shift time-weighted average (TWA) air samples and analyzed samples for HP, AA, and PAA content. Study participants were observed while they performed cleaning duties, and duration and frequency of cleaning product use was recorded. Acute upper airway, eye, and lower airway symptoms were recorded in a post-shift survey (n = 50). A subset of 35 cleaning staff also completed an extended questionnaire that assessed symptoms reported by workers as regularly occurring or as having occurred in the previous 12 months. Air samples for HP (range: 5.5 to 511.4 ppb) and AA (range: 6.7 to 530.3 ppb) were all below established US occupational exposure limits (OEL). To date, no full-shift TWA OEL for PAA has been established in the United States, however an OEL of 0.2 ppm has been suggested by several research groups. Air samples for PAA ranged from 1.1 to 48.0 ppb and were well below the suggested OEL of 0.2 ppm. Hospital cleaning staff using a sporicidal product containing HP, PAA, and AA reported work-shift eye (44%), upper airway (58%), and lower airway (34%) symptoms. Acute nasal and eye irritation were significantly positively associated with increased exposure to the mixture of the two oxidants: HP and PAA, as well as the total mixture (TM) of HP, PAA, and AA. Shortness of breath when hurrying on level ground or walking up a slight hill was significantly associated

Antidiabetic effect of Scoparia dulcis: effect on lipid peroxidation in streptozotocin diabetes.

Science.gov (United States)

Pari, L; Latha, M

2005-03-01

Oxidative damage has been suggested to be a contributory factor in the development and complications of diabetes. The antioxidant effect of an aqueous extract of Scoparia dulcis, an indigenous plant used in Ayurvedic medicine in India was studied in rats with streptozotocin-induced diabetes. Oral administration of Scoparia dulcis plant extract (SPEt) (200 mg/kg body weight) for 3 weeks resulted in a significant reduction in blood glucose and an increase in plasma insulin. The aqueous extract also resulted in decreased free radical formation in tissues (liver and kidney) studied. The decrease in thiobarbituric acid reactive substances (TBARS) and hydroperoxides (HPX) and increase in the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH) and glutathione-S-transferase (GST) clearly show the antioxidant properties of SPEt in addition to its antidiabetic effect. The effect of SPEt at 200 mg/kg body weight was better than glibenclamide, a reference drug.

Studies on qualitative and quantitative chemical changes in gamma-irradiated fish and fishery products of India

International Nuclear Information System (INIS)

Bandyopadhyay, C.

1978-01-01

There was an extension of shelf-life of irradiated mackerel (Rastrelliger kanagurta) upto 28 days at ice temperature (0-2 0 C) without any adverse effect on organoleptic attributes. No changes were observed in total lipids and non--saponifiable matter of irradiated fish during storage at 0.2 0 C. The changes in chemical indices including iodine value, peroxide value, thiobarbituric acid value, free fatty acid and glyceride content of irradiated fish samples were similar to that unirradiated ones during storage at 0-2 0 C. Thin-layer and gas-chromatographic studies on lipids did not reveal any detectable new component in irradiated fish samples. A definite suppression in the levels of total volatile basic nitrogen and trimethyl amine nitrogen was observed in irradiated samples compared to that in controls during storage at 0-2 0 C. (author)

Comparing the effects of different dietary organic acids on the growth, intestinal short-chain fatty acids, and liver histopathology of red hybrid tilapia (Oreochromis sp.) and potential use of these as preservatives.

Science.gov (United States)

Ebrahimi, Mahdi; Daeman, Nor Hafizah; Chong, Chou Min; Karami, Ali; Kumar, Vikas; Hoseinifar, Seyed Hossein; Romano, Nicholas

2017-08-01

Dietary organic acids are increasingly being investigated as a potential means of improving growth and nutrient utilization in aquatic animals. A 9-week study was performed to compare equal amounts (2%) of different organic acids (sodium butyrate, acetate, propionate, or formate) on the growth, muscle proximate composition, fatty acid composition, cholesterol and lipid peroxidation, differential cell counts, plasma biochemistry, intestinal short-chain fatty acid (SCFA) level, and liver histopathology to red hybrid tilapia (Oreochromis sp.) (initial mean weight of 2.87 g). A second experiment was performed to determine their effects on lipid peroxidation and trimethylamine (TMA) when added at 1% to tilapia meat and left out for 24 h. The results of the first experiment showed no treatment effect to growth, feeding efficiencies, or muscle fatty acid composition, but all dietary organic acids significantly decreased intestinal SCFA. Dietary butyrate and propionate significantly decreased muscle lipid peroxidation compared to the control group, but the dietary formate treatment had the lowest lipid peroxidation compared to all treatments. Muscle crude protein and lipid in tilapia fed the formate diet were significantly lower and higher, respectively, and showed evidence of stress based on the differential cell counts, significantly higher plasma glucose and liver glycogen, as well as inflammatory responses in the liver. Although a potential benefit of dietary organic acids was a reduction to lipid peroxidation, this could be accomplished post-harvest by direct additions to the meat. In addition, inclusions of butyrate and propionate to tilapia meat significantly decreased TMA, which might be a more cost-effective option to improve the shelf life of tilapia products.

Radiation-induced peroxidation of egg lecithin liposomes

International Nuclear Information System (INIS)

Bisby, R.H.; Cundall, R.B.; Tomaszewski, K.E.; Coleman, M.H.; Gould, G.

1983-01-01

Peroxidation of multilamellar vesicles of egg lecithin was measured following γ-irradiation of oxygen saturated suspensions. The addition of hydroxyl radical scavengers and the enzymes superoxide dismutase and catalase was used to show that hydroxyl radicals were the major species initiating peroxidation. Superoxide radicals were found to be much less effective initiators of peroxidation. Trolox C, a water soluble analogue of vitamin E, was found to act as an efficient antioxidant in this system. (author)

7 CFR 58.431 - Hydrogen peroxide.

Science.gov (United States)

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Hydrogen peroxide. 58.431 Section 58.431 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.431 Hydrogen peroxide. The solution shall comply with the specification of the U.S...

Mechanisms of DNA damage by the tumor promoter and progressor benzoyl peroxide

International Nuclear Information System (INIS)

Swauger, J.E.; Dolan, P.M.; Zweier, J.L.; Kensler, T.W.

1990-01-01

Benzoyl peroxide (BzPO), a tumor promoter and progressor in mouse skin, produces strand breaks in DNA of exposed cells. Previously we have reported that the metabolism of BzPO in keratinocytes proceeds via the initial cleavage of the peroxide bond, yielding benzoyloxyl radicals which, in turn, can fragment to form phenyl radicals and carbon dioxide. Benzoic acid, the product of hydrogen abstraction by the benzoyloxyl radical, is the major stable metabolite of BzPO produced by keratinocytes. In the present study we have examined the capacity of BzPO to generate strand scissions in φX-174 plasmid DNA. DNA damage was dose-dependent over a concentration range of 10-1000 μM BzPO and was dependent on the presence of copper but not other transition state metals. By contrast, benzoic acid did not produce DNA damage in this system. The inclusion of spin trapping agents (PBN, DBNBS), radical scavenging agents (Nal, GSH), or the copper chelator o-phenanthroline in incubations was found to significantly reduce the extent of DNA damage. Electron paramagnetic resonance spectroscopy studies suggested that the primary radical trapped was the benzoyloxyl radical, implying a role for this radical in the generation of the observed DNA damage. Collectively these observations suggest BzPO may be activated to DNA damaging intermediates in keratinocytes via metal-catalyzed cleavage of the peroxide bond resulting in the formation of the benzoyloxyl radical. Covalent modification of DNA was not observed when [ 14 C]BzPO was incubated with calf thymus DNA in the presence of copper. Overall, these results suggest that BzPO induces DNA damage via benzoyloxyl radical mediated proton abstraction from the DNA strand and the adduct formation with DNA is unlikely to occur

Radioprotective effect of both vitamins E and / or C on some blood components of male mice

International Nuclear Information System (INIS)

Anwar, W.A.; El-Daway, H.A.E.; Tawfik, S.S.M.; Soliman, S.M.

1999-01-01

The protective effects of vitamin C and/or vitamin E on some blood components and serum level of thiobarbituric reactive substances (as indicator to level of lipid peroxidation) of irradiated male mice at dose 3 Gy sacrificed after 15,24 and 46 days of irradiation have been assessed in comparison with control and non-irradiated-treated with vitamin C and/or vitamin E groups. Vit. C, vit. E or in combination decreased the effect of irradiation on blood components and the level of thiobarbituric reactive substances, but average haemoglobin level RBC count, total WBC count, neutrophil count and lymphocyte count did not reach to the original average level even after 36 days of irradiation. Vit. E had a more protective effect than vit. C in case of total white blood cells, while vit. C was more protective in case of lymphocyte count. The combination of vitamins C and E had more protective effect than either of both vitamins alone. The decrease in lipid peroxidation products due to administration of vit. E and vit. C as antioxidants supported the theory that lipid peroxidation increased due to free radicals induced by irradiation

PEROXIDE PROCESS FOR SEPARATION OF RADIOACTIVE MATERIALS

Science.gov (United States)

Seaborg, G.T.; Perlman, I.

1958-09-16

reduced state, from hexavalent uranium. It consists in treating an aqueous solution containing such uranium and plutonium ions with sulfate ions in order to form a soluble uranium sulfate complex and then treating the solution with a soluble thorium compound and a soluble peroxide compound in order to ferm a thorium peroxide carrier precipitate which carries down with it the plutonium peroxide present. During this treatment the pH of the solution must be maintained between 2 and 3.

Antioxidant effect of bisphosphonates and simvastatin on chondrocyte lipid peroxidation

International Nuclear Information System (INIS)

Dombrecht, E.J.; De Tollenaere, C.B.; Aerts, K.; Cos, P.; Schuerwegh, A.J.; Bridts, C.H.; Van Offel, J.F.; Ebo, D.G.; Stevens, W.J.; De Clerck, L.S.

2006-01-01

The objective of this study was to evaluate the effect of bisphosphonates (BPs) and simvastatin on chondrocyte lipid peroxidation. For this purpose, a flow cytometrical method using C11-BODIPY 581/591 was developed to detect hydroperoxide-induced lipid peroxidation in chondrocytes. Tertiary butylhydroperoxide (t-BHP) induced a time and concentration dependent increase in chondrocyte lipid peroxidation. Addition of a Fe 2+ /EDTA complex to t-BHP or hydrogen peroxide (H 2 O 2 ) clearly enhanced lipid peroxidation. The lipophilic simvastatin demonstrated a small inhibition in the chondrocyte lipid peroxidation. None of three tested BPs (clodronate, pamidronate, and risedronate) had an effect on chondrocyte lipid peroxidation induced by t-BHP. However, when Fe 2+ /EDTA complex was added to t-BHP or H 2 O 2 , BPs inhibited the lipid peroxidation process varying from 25% to 58%. This study demonstrates that BPs have antioxidant properties as iron chelators, thereby inhibiting the chondrocyte lipid peroxidation. These findings add evidence to the therapeutic potential of bisphosphonates and statins in rheumatoid arthritis

Salicylic acid induces apoptosis in colon carcinoma cells grown in-vitro: Influence of oxygen and salicylic acid concentration

Energy Technology Data Exchange (ETDEWEB)

Zitta, Karina; Meybohm, Patrick; Bein, Berthold; Huang, Ying; Heinrich, Christin; Scholz, Jens; Steinfath, Markus; Albrecht, Martin, E-mail: Albrecht@anaesthesie.uni-kiel.de

2012-04-15

In solid tumors the hypoxic environment can promote tumor progression and resistance to therapy. Recently, acetylsalicylic acid a major component of analgesic drugs and its metabolite salicylic acid (SA) have been shown to reduce the risk of colon cancer, but the mechanisms of action remain still unclear. Here we elucidate the effects of physiologically relevant concentrations of SA on colon carcinoma cells (CaCo-2) grown under normoxic and hypoxic conditions. Western blotting, caspase-3/7 apoptosis assays, MTS cell-proliferation assays, LDH cytotoxicity assays and hydrogen peroxide measurements were performed to investigate the effects of 1 and 10 {mu}M SA on CaCo-2 cells grown under normoxic conditions and cells exposed to hypoxia. Under normoxic conditions, SA did not influence cell proliferation or LDH release of CaCo-2 cells. However, caspase-3/7 activity was significantly increased. Under hypoxia, cell proliferation was reduced and LDH release and caspase-3/7 activities were increased. None of these parameters was altered by the addition of SA under hypoxic conditions. Hypoxia increased hydrogen peroxide concentrations 300-fold and SA significantly augmented the release of hydrogen peroxide under normoxic, but not under hypoxic conditions. Phosphorylation of the pro-survival kinases akt and erk1/2 was not changed by SA under hypoxic conditions, whereas under normoxia SA reduced phosphorylation of erk1/2 after 2 hours. We conclude that in colon carcinoma cells effects of SA on apoptosis and cellular signaling are dependent on the availability of oxygen. -- Highlights: Black-Right-Pointing-Pointer Effects of salicylic acid on colon carcinoma cells grown under normoxic and hypoxic conditions Black-Right-Pointing-Pointer Salicylic acid increases caspase-3/7 activity and hydrogen peroxide release under normoxia Black-Right-Pointing-Pointer Salicylic acid decreases pro-survival erk-1/2 phosphorylation under normoxia Black-Right-Pointing-Pointer Salicylic acid does

Microsomal lipid peroxidation as a mechanism of cellular damage. [Dissertation

Energy Technology Data Exchange (ETDEWEB)

Kornbrust, D.J.

1979-01-01

The NADPH/iron-dependent peroxidation of lipids in rat liver microsomes was found to be dependent on the presence of free ferrous ion and maintains iron in the reduced Fe/sup 2 +/ state. Chelation of iron by EDTA inhibited peroxidation. Addition of iron, after preincubation of microsomes in the absence of iron, did not enhance the rate of peroxidation suggesting that iron acts by initiating peroxidative decomposition of membrane lipids rather than by catalyzing the breakdown of pre-formed hydroperoxides. Liposomes also underwent peroxidation in the presence of ferrous iron at a rate comparable to intact microsomes and was stimulated by ascorbate. Carbon tetrachloride initiated lipid peroxidation in the absence of free metal ions. Rates of in vitro lipid peroxidation of microsomes and homogenates were found to vary widely between different tissues and species. The effects of paraquat on lipid peroxidation was also studied. (DC)

Inorganic precursor peroxides for antifouling coatings

DEFF Research Database (Denmark)

Olsen, S.M.; Pedersen, L.T.; Hermann, M.H.

2009-01-01

Modern antifouling coatings are generally based on cuprous oxide (Cu2O) and organic biocides as active ingredients. Cu2O is prone to bioaccumulation, and should therefore be replaced by more environmentally benign compounds when technically possible. However, cuprous oxide does not only provide...... antifouling properties, it is also a vital ingredient for the antifouling coating to obtain its polishing and leaching mechanism. In this paper, peroxides of strontium, calcium, magnesium, and zinc are tested as pigments in antifouling coatings. The peroxides react with seawater to create hydrogen peroxide...... matrix provides antifouling properties exceeding those of a similar coating based entirely on zinc oxide....

Correlation of serum paraoxonase activities in known cases of 130 elderly hypertensive South Asian aged 56-64 years - a hospital based study

Directory of Open Access Journals (Sweden)

Arun Kumar

2014-02-01

Full Text Available Objective: To evaluate paraoxonase activity, antioxidant status and lipid peroxidation in hypertensive participants and to address the hypothesis that oxidative modifications of lipids due to hypertension can cause changes in serum paraoxonase activities. Methods: The serum paraoxonase activities, antioxidants and lipid peroxidation were determined in 130 hypertensive participants and 130 age-sexes matched normotensive healthy volunteers served as control. Serum paraoxonase activities were measured by enzymatic kit. The glutathione peroxidase, superoxide dismutase and catalase activity were determined by standard methods. Malondialdehyde was measured by thiobarbituric acid reaction. Conjugated diene level was measured by Recknagel and Glende method. Serum uric acid, total bilirubin, serum albumin, serum ascorbic acid and lipid profile were analyzed by standard methods. Results: Total cholesterol, triglycerides, low-density lipoprotein cholesterol were significantly higher and high-density lipoprotein cholesterol were significantly lower in hypertensive patients when compared to normotensive healthy controls. The superoxide dismutase, glutathione peroxidase and catalase were significantly lower in hypertensive when compared with normotensive. Similar findings were observed in the levels of albumin, uric acid, bilirubin and ascorbic acid when hypertensives were compared with normotensive. The oxidative stress indicators namely malondialdehyde and conjugated diene were significantly higher and paraoxonase activity were significantly lower in hypertensive. Conclusions: Our study concludes that paraoxonase activities are bound to alter in hypertension which is caused due to interplay of several confounding factors namely oxidative stress, increased oxidized low-density lipoprotein and depletion of antioxidants.

EFFLUENT TREATMENT FACILITY PEROXIDE DESTRUCTION CATALYST TESTING

International Nuclear Information System (INIS)

HALGREN DL

2008-01-01

The 200 Area Effluent Treatment Facility (ETF) main treatment train includes the peroxide destruction module (PDM) where the hydrogen peroxide residual from the upstream ultraviolet light/hydrogen peroxide oxidation unit is destroyed. Removal of the residual peroxide is necessary to protect downstream membranes from the strong oxidizer. The main component of the PDM is two reaction vessels utilizing granular activated carbon (GAC) as the reaction media. The PDM experienced a number of operability problems, including frequent plugging, and has not been utilized since the ETF changed to groundwater as the predominant feed. The unit seemed to be underperforming in regards to peroxide removal during the early periods of operation as well. It is anticipated that a functional PDM will be required for wastewater from the vitrification plant and other future streams. An alternate media or methodology needs to be identified to replace the GAC in the PDMs. This series of bench scale tests is to develop information to support an engineering study on the options for replacement of the existing GAC method for peroxide destruction at the ETF. A number of different catalysts will be compared as well as other potential methods such as strong reducing agents. The testing should lead to general conclusions on the viability of different catalysts and identify candidates for further study and evaluation

Direct electron transfer biosensor for hydrogen peroxide carrying nanocomplex composed of horseradish peroxidase and Au-nanoparticle – Characterization and application to bienzyme systems

Directory of Open Access Journals (Sweden)

Yusuke Okawa

2015-09-01

Full Text Available A reagentless electrochemical biosensor for hydrogen peroxide was fabricated. The sensor carries a monolayer of nanocomplex composed of horseradish peroxidase and Au-nanoparticle, and responds to hydrogen peroxide through the highly efficient direct electron transfer at a mild electrode potential without any soluble mediator. Formation of the nanocomplex was studied with visible spectroscopy and size exclusion chromatography. The sensor performance was analyzed based on a hydrodynamic electrochemical technique and enzyme kinetics. The sensor was applied to fabrication of sensors for glucose and uric acid through further modification of the nanocomplex-carrying electrode with the corresponding hydrogen peroxide-generating oxidases, glucose oxidase and urate oxidase, respectively.

Ionizing radiation and lipid peroxidation in human body

International Nuclear Information System (INIS)

Giubileo, Gianfranco

1997-07-01

Lipids are organic compounds constituting the living cells. Lipid molecules can be disassembled through peroxidative pathways and hydrocarbons can be bred as end-product of lipid peroxidation in vivo. Lipid peroxidation can be started by an indirect effect of ionizing radiation. So a radioinduced cellular damage in human body can be detected by monitoring the production of specific hydrocarbons

Synergistic inactivation of anaerobic wastewater biofilm by free nitrous acid and hydrogen peroxide

International Nuclear Information System (INIS)

Jiang, Guangming; Yuan, Zhiguo

2013-01-01

Highlights: ► H 2 O 2 greatly enhances the inactivation of microorganisms in biofilms by FNA. ► About 2-log of inactivation of biofilm microbes was achieved by FNA + H 2 O 2 . ► FNA + H 2 O 2 reduced sulfide production and detached biofilm in reactors. -- Abstract: Free nitrous acid (FNA) was recently revealed to be a strong biocide for microbes in anaerobic biofilm, achieving approximately 1-log (90%) inactivation at a concentration of 0.2–0.3 mgHNO 2 -N/L with an exposure time longer than 6 h. The combined biocidal effects of FNA and hydrogen peroxide (H 2 O 2 ) on anaerobic wastewater biofilm are investigated in this study. H 2 O 2 greatly enhances the inactivation of microorganisms by FNA. About 2-log (99%) of microbial inactivation was achieved when biofilms were exposed to FNA at 0.2 mgN/L or above and H 2 O 2 at 30 mg/L or above for 6 h or longer. It was found, through response surface methodology and ridge analysis, that FNA is the primary inactivation agent and H 2 O 2 enhances its efficiency. The loss and the subsequent slow recovery of biological activity in biofilm reactors subjected to FNA and H 2 O 2 dosing confirmed that the chemical combination could achieve higher microbial inactivation than with FNA alone. Reaction simulation shows that intermediates of reactions between FNA and H 2 O 2 , like peroxynitrite and nitrogen dioxide, would be produced at elevated levels and are likely responsible for the synergism between FNA and H 2 O 2 . The combination of FNA and H 2 O 2 could potentially provide an effective solution to sewer biofilm control

Synergistic inactivation of anaerobic wastewater biofilm by free nitrous acid and hydrogen peroxide

Energy Technology Data Exchange (ETDEWEB)

Jiang, Guangming, E-mail: gjiang@awmc.uq.edu.au [Advanced Water Management Centre, Gehrmann Building, Research Road, The University of Queensland, St. Lucia, Queensland 4072 (Australia); Yuan, Zhiguo, E-mail: zhiguo@awmc.uq.edu.au [Advanced Water Management Centre, Gehrmann Building, Research Road, The University of Queensland, St. Lucia, Queensland 4072 (Australia)

2013-04-15

Highlights: ► H{sub 2}O{sub 2} greatly enhances the inactivation of microorganisms in biofilms by FNA. ► About 2-log of inactivation of biofilm microbes was achieved by FNA + H{sub 2}O{sub 2}. ► FNA + H{sub 2}O{sub 2} reduced sulfide production and detached biofilm in reactors. -- Abstract: Free nitrous acid (FNA) was recently revealed to be a strong biocide for microbes in anaerobic biofilm, achieving approximately 1-log (90%) inactivation at a concentration of 0.2–0.3 mgHNO{sub 2}-N/L with an exposure time longer than 6 h. The combined biocidal effects of FNA and hydrogen peroxide (H{sub 2}O{sub 2}) on anaerobic wastewater biofilm are investigated in this study. H{sub 2}O{sub 2} greatly enhances the inactivation of microorganisms by FNA. About 2-log (99%) of microbial inactivation was achieved when biofilms were exposed to FNA at 0.2 mgN/L or above and H{sub 2}O{sub 2} at 30 mg/L or above for 6 h or longer. It was found, through response surface methodology and ridge analysis, that FNA is the primary inactivation agent and H{sub 2}O{sub 2} enhances its efficiency. The loss and the subsequent slow recovery of biological activity in biofilm reactors subjected to FNA and H{sub 2}O{sub 2} dosing confirmed that the chemical combination could achieve higher microbial inactivation than with FNA alone. Reaction simulation shows that intermediates of reactions between FNA and H{sub 2}O{sub 2}, like peroxynitrite and nitrogen dioxide, would be produced at elevated levels and are likely responsible for the synergism between FNA and H{sub 2}O{sub 2}. The combination of FNA and H{sub 2}O{sub 2} could potentially provide an effective solution to sewer biofilm control.

Destruction of gel sulfonated cation-exchangers of the KU-2 type under the influence of hydrogen peroxide

Energy Technology Data Exchange (ETDEWEB)

Roginskaya, B.S.; Zavadovskaya, A.S.; Znamenskii, Yu.P.; Paskhina, N.A.; Dobrova, E.I.

1988-10-20

The purpose of this work was to study the mechanism of interaction of Soviet sulfonated cation-exchangers of the KU-2 type with hydrogen peroxide. It is shown that under the influence of hydrogen peroxide sulfonated cation-exchangers begin, after a certain induction period, to lose capacity and to release destruction products into water; the length of the induction period increases with the degree of cross-linking. In a given time of contact between the resin and the solution the degree of destruction falls with increase of cross-linking. The principal product of destruction of sulfonated cation-exchangers is an aromatic sulfonic acid containing oxidized groups in the side chains.

No Evidence of Racial Differences in Endothelial Function and Exercise Blood Flow in Young, Healthy Males Following Acute Antioxidant Supplementation.

Science.gov (United States)

Kappus, Rebecca M; Bunsawat, Kanokwan; Rosenberg, Alexander J; Fernhall, Bo

2017-03-01

This study investigated the effects of acute antioxidant supplementation on endothelial function, exercise blood flow and oxidative stress biomarkers in 9 young African American compared to 10 Caucasian males (25.7±1.2 years). We hypothesized that African American males would have lower exercise blood flow and endothelial responsiveness compared to Caucasian males, and these responses would be improved following antioxidant supplementation. Ultrasonography was used to measure blood flow during handgrip exercise. Endothelial function was assessed using flow-mediated dilation, and lipid peroxidation was assessed by measuring levels of malondialdehyde-thiobarbituric acid reactive substances. African American males exhibited lower endothelial function than Caucasians at baseline (8.3±1.7 vs. 12.2±1.7%) and the difference was ameliorated with antioxidant supplementation (10.7±1.9% vs. 10.8±1.8%), but the interaction was not significant (p=0.10). There were no significant changes in malondialdehyde-thiobarbituric acid reactive substances following antioxidant supplementation. There was a significant increase in brachial blood flow and forearm vascular conductance with exercise but no differences with antioxidant supplementation. There were no group differences in exercise responses and no differences with antioxidant supplementation, suggesting a lack of influence of oxidative stress during exercise in this cohort. © Georg Thieme Verlag KG Stuttgart · New York.

Research Advances: Horseradish Peroxide Mixture May End War of the Noses-- Even Low Levels of Benzene Are Hemotoxic--New "Nuclear Battery" Runs 10 Years. 10 Times More Powerful

Science.gov (United States)

King, Angela G.

2005-01-01

Experts have mixed horseradish root with hydrogen peroxide or calcium peroxide in laboratory studies to get rid of the problem of odors from farm manure. Researchers evaluated how well the system reduced the concentration of volatile fatty acids, indole and skatole, compounds that are also associated with the stink of animal manure.

Ascorbic acid protects lipids in human plasma and low-density lipoprotein against oxidative damage

Energy Technology Data Exchange (ETDEWEB)

Frei, B. (Department of Nutrition, Harvard School of Public Health, Boston, MA (Unites States))

1991-12-01

The authors exposed human blood plasma and low-density lipoprotein (LDL) to many different oxidative challenges and followed the temporal consumption of endogenous antioxidants in relation to the initiation of oxidative damage. Under all types of oxidizing conditions, ascorbic acid completely protects lipids in plasma and LDL against detectable peroxidative damage as assessed by a specific and highly sensitive assay for lipid peroxidation. Ascorbic acid proved to be superior to the other water-soluble plasma antioxidants bilirubin, uric acid, and protein thiols as well as to the lipoprotein-associated antioxidants alpha-tocopherol, ubiquinol-10, lycopene, and beta-carotene. Although these antioxidants can lower the rate of detectable lipid peroxidation, they are not able to prevent its initiation. Only ascorbic acid is reactive enough to effectively intercept oxidants in the aqueous phase before they can attack and cause detectable oxidative damage to lipids.

Optimizing Phosphoric Acid plus Hydrogen Peroxide (PHP) Pretreatment on Wheat Straw by Response Surface Method for Enzymatic Saccharification.

Science.gov (United States)

Qiu, Jingwen; Wang, Qing; Shen, Fei; Yang, Gang; Zhang, Yanzong; Deng, Shihuai; Zhang, Jing; Zeng, Yongmei; Song, Chun

2017-03-01

Wheat straw was pretreated by phosphoric acid plus hydrogen peroxide (PHP), in which temperature, time, and H 3 PO 4 proportion for pretreatment were investigated by using response surface method. Results indicated that hemicellulose and lignin removal positively responded to the increase of pretreatment temperature, H 3 PO 4 proportion, and time. H 3 PO 4 proportion was the most important variable to control cellulose recovery, followed by pretreatment temperature and time. Moreover, these three variables all negatively related to cellulose recovery. Increasing H 3 PO 4 proportion can improve enzymatic hydrolysis; however, reduction on cellulose recovery results in decrease of glucose yield. Extra high temperature or long time for pretreatment was not beneficial to enzymatic hydrolysis and glucose yield. Based on the criterion for minimizing H 3 PO 4 usage and maximizing glucose yield, the optimized pretreatment conditions was 40 °C, 2.0 h, and H 3 PO 4 proportion of 70.2 % (H 2 O 2 proportion of 5.2 %), by which glucose yielded 299 mg/g wheat straw (946.2 mg/g cellulose) after 72-h enzymatic hydrolysis.

PROCESS OF ELIMINATING HYDROGEN PEROXIDE IN SOLUTIONS CONTAINING PLUTONIUM VALUES

Science.gov (United States)

Barrick, J.G.; Fries, B.A.

1960-09-27

A procedure is given for peroxide precipitation processes for separating and recovering plutonium values contained in an aqueous solution. When plutonium peroxide is precipitated from an aqueous solution, the supernatant contains appreciable quantities of plutonium and peroxide. It is desirable to process this solution further to recover plutonium contained therein, but the presence of the peroxide introduces difficulties; residual hydrogen peroxide contained in the supernatant solution is eliminated by adding a nitrite or a sulfite to this solution.

Hippophae rhamnoides L. Fruits Reduce the Oxidative Stress in Human Blood Platelets and Plasma

Directory of Open Access Journals (Sweden)

Beata Olas

2016-01-01

Full Text Available Effects of the phenolic fraction from Hippophae rhamnoides fruits on the production of thiobarbituric acid reactive substances (TBARS, a marker of lipid peroxidation and the generation of superoxide anion (O2-∙ in human blood platelets (resting platelets and platelets stimulated by a strong physiological agonist, thrombin were studied in vitro. We also examined antioxidant properties of this fraction against human plasma lipid peroxidation and protein carbonylation induced by a strong biological oxidant, hydrogen peroxide (H2O2 or H2O2/Fe (a donor of hydroxyl radicals. The tested fraction of H. rhamnoides (0.5– 50 µg/mL; the incubation time: 15 and 60 min inhibited lipid peroxidation induced by H2O2 or H2O2/Fe. The H. rhamnoides phenolic fraction inhibited not only plasma lipid peroxidation, but also plasma protein carbonylation stimulated by H2O2 or H2O2/Fe. Moreover, the level of O2-∙ in platelets significantly decreased. In comparative experiments, the H. rhamnoides fraction was a more effective antioxidant than aronia extract or grape seed extract (at the highest tested concentration, 50 µg/mL. The obtained results suggest that H. rhamnoides fruits may be a new, promising source of natural compounds with antioxidant and antiplatelet activity beneficial not only for healthy people, but also for those with oxidative stress-associated diseases.

Determination of fatty acid composition of {gamma}-irradiated hazelnuts, walnuts, almonds, and pistachios

Energy Technology Data Exchange (ETDEWEB)

Gecgel, Umit [Namik Kemal University, Agricultural Faculty, Department of Food Engineering, 59030 Tekirdag (Turkey); Gumus, Tuncay; Tasan, Murat; Daglioglu, Orhan; Arici, Muhammet [Namik Kemal University, Agricultural Faculty, Department of Food Engineering, 59030 Tekirdag (Turkey)

2011-04-15

Hazelnut, walnut, almonds, and pistachio nuts were treated with 1, 3, 5, and 7 kGy of gamma irradiation, respectively. Oil content, free fatty acid, peroxide value, and fatty acid composition of the nuts were investigated immediately after irradiation. The data obtained from the experiments indicated that gamma irradiation did not cause any significant change in the oil content of nuts. In contrast, free fatty acid and peroxide value of the nuts increased proportionally to the dose (p<0.05). Among the fatty acids determined, the concentration of total saturated fatty acids increased while total monounsaturated and total polyunsaturated fatty acids decreased with the irradiation dose (p<0.05 and <0.01).

Determination of fatty acid composition of γ-irradiated hazelnuts, walnuts, almonds, and pistachios

International Nuclear Information System (INIS)

Gecgel, Umit; Gumus, Tuncay; Tasan, Murat; Daglioglu, Orhan; Arici, Muhammet

2011-01-01

Hazelnut, walnut, almonds, and pistachio nuts were treated with 1, 3, 5, and 7 kGy of gamma irradiation, respectively. Oil content, free fatty acid, peroxide value, and fatty acid composition of the nuts were investigated immediately after irradiation. The data obtained from the experiments indicated that gamma irradiation did not cause any significant change in the oil content of nuts. In contrast, free fatty acid and peroxide value of the nuts increased proportionally to the dose (p<0.05). Among the fatty acids determined, the concentration of total saturated fatty acids increased while total monounsaturated and total polyunsaturated fatty acids decreased with the irradiation dose (p<0.05 and <0.01).

Determination of fatty acid composition of γ-irradiated hazelnuts, walnuts, almonds, and pistachios

Science.gov (United States)

Gecgel, Umit; Gumus, Tuncay; Tasan, Murat; Daglioglu, Orhan; Arici, Muhammet

2011-04-01

Hazelnut, walnut, almonds, and pistachio nuts were treated with 1, 3, 5, and 7 kGy of gamma irradiation, respectively. Oil content, free fatty acid, peroxide value, and fatty acid composition of the nuts were investigated immediately after irradiation. The data obtained from the experiments indicated that gamma irradiation did not cause any significant change in the oil content of nuts. In contrast, free fatty acid and peroxide value of the nuts increased proportionally to the dose (p<0.05). Among the fatty acids determined, the concentration of total saturated fatty acids increased while total monounsaturated and total polyunsaturated fatty acids decreased with the irradiation dose (p<0.05 and <0.01).

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

Science.gov (United States)

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

2015-12-07

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

[Effect of Residual Hydrogen Peroxide on Hydrolysis Acidification of Sludge Pretreated by Microwave -H2O2-Alkaline Process].

Science.gov (United States)

Jia, Rui-lai; Liu, Ji-bao; Wei, Yuan-song; Cai, Xing

2015-10-01

Previous studies have found that in the hydrolysis acidification process, sludge after microwave -H2O2-alkaline (MW-H2O2-OH, pH = 10) pretreatment had an acid production lag due to the residual hydrogen peroxide. In this study, effects of residual hydrogen peroxide after MW-H2O2-OH (pH = 10 or pH = 11) pretreatment on the sludge hydrolysis acidification were investigated through batch experiments. Our results showed that catalase had a higher catalytic efficiency than manganese dioxide for hydrogen peroxide, which could completely degraded hydrogen peroxide within 10 min. During the 8 d of hydrolysis acidification time, both SCOD concentrations and the total VFAs concentrations of four groups were firstly increased and then decreased. The optimized hydrolysis times were 0.5 d for four groups, and the optimized hydrolysis acidification times were 3 d for MW-H2O2-OH (pH = 10) group, MW-H2O2-OH (pH = 10) + catalase group and MW-H2O2-OH (pH = 11) + catalase group. The optimized hydrolysis acidification time for MW-H2O2-OH (pH = 11) group was 4 d. Residual hydrogen peroxide inhibited acid production for sludge after MW-H2O2-OH (pH = 10) pretreatment, resulting in a lag in acidification stage. Compared with MW-H2O2-OH ( pH = 10) pretreatment, MW-H2O2-OH (pH = 11 ) pretreatment released more SCOD by 19.29% and more organic matters, which resulted in the increase of total VFAs production significantly by 84.80% at 5 d of hydrolysis acidification time and MW-H2O2-OH (pH = 11) group could shorten the lag time slightly. Dosing catalase (100 mg x -L(-1)) after the MW-H2O2-OH (pH = 10 or pH = 11) pretreatment not only significantly shortened the lag time (0.5 d) in acidification stage, but also produced more total VFAs by 23.61% and 50.12% in the MW-H2O2-OH (pH = 10) + catalase group and MW-H2O2-OH (pH = 11) + catalase group, compared with MW-H2O2-OH (pH = 10) group at 3d of hydrolysis acidification time. For MW-H2O2-OH (pH = 10) group, MW-H2O2-OH (pH = 10) + catalase group and

Influence of supplemental ultraviolet-B radiation on lipid peroxidation of Chinese cabbage

International Nuclear Information System (INIS)

Huang Shaobai; Zhang Jingjuan; Liu Xiaozhong

1998-01-01

Chinese cabbage cultivar Aijiaohuang was grown in an indoor experiment treated by 0.0,130 (simulating 20% ozone depletion)kJm~(-2)day~(-1) of ultraviolet-B(UV-B) for 4 and 7 days to study the effect of supplemental UV-B radiation on flavoniods and lipid peroxidation in the leaves of Chinese cabbage. Accumulation of UV-ABSORBING flavonoids in the leaves of Chinese cabbage was induced by UV-B radiation. Enhanced UV-B radiation reduced ascorbic acid content in the leaves of Chinese cabbage. It was also found that 13.0kJm~(2)day~(-1) UV-B inhibited catalase and superoxide dismutase activities and increased malondiadehyde content in the leaves of Chinese cabbage. These effects induced by UV-B radiation was enhanced with the time course of treatment. The results above suggested that supplemental UV-B radiation enhanced lipid peroxidation of Chinese cabbage, and the accumulation of UV-absorbing flavonoid could not alleviate the damage of UV-B radiation

Blood lipid peroxides and muscle damage increased following intensive resistance training of female weightlifters.

Science.gov (United States)

Liu, Jen-Fang; Chang, Wei-Yin; Chan, Kuei-Hui; Tsai, Wen-Yee; Lin, Chen-Li; Hsu, Mei-Chieh

2005-05-01

The aim of this study was to examine changes in muscle cell injury and antioxidant capacity of weightlifters following a 1-week intensive resistance-training regimen. Thirty-six female subjects participated in this study, and their ages ranged from 18 to 25 years. The sample group included 19 elite weightlifters with more than 3 years of weightlifting training experience, while the control group comprised 17 non-athletic individuals. Compared with non-athletes, weightlifters had significantly lower glutathione peroxidase activity and plasma vitamin C concentrations. Weightlifters also had significantly higher malondialdehyde + 4-hydroxy 2-(E)-nonenal (MDA+4-HNE) and thiobarbituric acid-reactive substance (TBARS) levels and creatine kinase (CK) activity. For weightlifters, the plasma vitamin E level and the activity of superoxide dismutase (SOD) decreased, and CK activity increased significantly (P weightlifters (P injury in female weightlifters. Furthermore, proper rest after intensive training was found to be important for recovery.

Kinetic model of water disinfection using peracetic acid including synergistic effects.

Science.gov (United States)

Flores, Marina J; Brandi, Rodolfo J; Cassano, Alberto E; Labas, Marisol D

2016-01-01

The disinfection efficiencies of a commercial mixture of peracetic acid against Escherichia coli were studied in laboratory scale experiments. The joint and separate action of two disinfectant agents, hydrogen peroxide and peracetic acid, were evaluated in order to observe synergistic effects. A kinetic model for each component of the mixture and for the commercial mixture was proposed. Through simple mathematical equations, the model describes different stages of attack by disinfectants during the inactivation process. Based on the experiments and the kinetic parameters obtained, it could be established that the efficiency of hydrogen peroxide was much lower than that of peracetic acid alone. However, the contribution of hydrogen peroxide was very important in the commercial mixture. It should be noted that this improvement occurred only after peracetic acid had initiated the attack on the cell. This synergistic effect was successfully explained by the proposed scheme and was verified by experimental results. Besides providing a clearer mechanistic understanding of water disinfection, such models may improve our ability to design reactors.

Thermometric sensing of peroxide in organic media. Application to monitor the stability of RBP-retinol-HRP complex.

Science.gov (United States)

Ramanathan, K; Jönsson, B R; Danielsson, B

2000-08-01

The stability of horseradish peroxidase (HRP) in aqueous and organic solvents is applied to develop a simple thermometric procedure to detect the binding of retinoic acid-HRP conjugate to retinol binding protein (RBP). Butanone peroxide (BP) in organic phase and hydrogen peroxide in aqueous phase is detected thermometrically on a HRP column, immobilized by cross-linking with glutaraldehyde on controlled pore glass (CPG). Acetone, acetonitrile, methanol, and 2-butanol are used for detection of BP, in the flow injection analysis (FIA) mode. A linear range between 1 and 50 mM BP is obtained in all the organic solvents with a precision of 5-7% (CV%). The magnitude and nature of the thermometric response is significantly different in each organic solvent. The stability of HRP in the organic phase is used to study the stability of a retinoic acid-HRP conjugate bound to immobilized RBP. The response of HRP (to 20 mM BP) in the retinoic acid-HRP conjugate is used as an indicator of the stability of the RBP-retinoic acid-HRP complex, after challenges with various organic/aqueous solvents. Both immobilized HRP and RBP are stable at least for 6 months. The effect of o-phenylene diamine on the thermometric response of HRP is also investigated. A scheme for the design of a thermometric retinol (vitamin A) biosensor is proposed.

Clovamide-rich extract from Trifolium pallidum reduces oxidative stress-induced damage to blood platelets and plasma.

Science.gov (United States)

Kolodziejczyk, Joanna; Olas, Beata; Wachowicz, Barbara; Szajwaj, Barbara; Stochmal, Anna; Oleszek, Wieslaw

2011-09-01

Numerous plants (including clovers) have been widely used in folk medicine for the treatment of different disorders. This in vitro study was designed to examine the antioxidative effects of the clovamide-rich fraction, obtained from aerial parts of Trifolium pallidum, in the protection of blood platelets and plasma against the nitrative and oxidative damage, caused by peroxynitrite (ONOO(-)). Carbonyl groups and 3-nitrotyrosine in blood platelet and plasma proteins were determined by ELISA tests. Thiol groups level was estimated by using 5,5'-dithio-bis(2-nitro-benzoic acid, DTNB). Plasma lipid peroxidation was measured spectrophotometrically as the production of thiobarbituric acid reactive substances. The results from our work indicate that clovamide-rich T. pallidum extract may reveal the protective properties in the prevention against oxidative stress. The presence of clovamide-rich T. pallidum extract (12.5-100 μg/ml) partly inhibited ONOO(-)-mediated protein carbonylation and nitration. All the used concentrations of T. pallidum extract reduced lipid peroxidation in plasma. The antioxidative action of the tested extract in the protection of blood platelet lipids was less effective; the extract at the lowest final concentration (12.5 μg/ml) had no protective effect against lipid peroxidation. The present results indicate that the extract from T. pallidum is likely to be a source of compounds with the antioxidative properties, useful in the prevention against the oxidative stress-related diseases.

Degradation of chitosan by gamma ray with presence of hydrogen peroxide

Energy Technology Data Exchange (ETDEWEB)

Mahmud, Maznah; Yacob, Norzita; Talip, Norhashidah; Abdullah, Zahid [Malaysian Nuclear Agency, Radiation Technology Division, Bangi, 43000 Kajang, Selangor (Malaysia); Naziri, Muhammad Ihsan [University of Malaya, 50603 Kuala Lumpur (Malaysia)

2014-02-12

The radiation degraded chitosan samples were prepared by swelling the chitosan powder in water and exposed for gamma irradiation. The ratio chitosan to water was 1:6 with the presence of hydrogen peroxide (H{sub 2}O{sub 2}), 1%–5%. These chitosan-water mixtures were irradiated at 6kGy, which is the lowest irradiation dose that facility can offered. All samples were purified and proceed with characterization. The molecular weight (MW) study was monitored by size exclusion chromatography-multi angle laser light scattering (SEC-MALLS). Results showed that MW of chitosan reduced as the dose increased. Application of H{sub 2}O{sub 2} enhanced the degradation rate of chitosan even at very low irradiation dose. Homogenous degradation also occurred during treatment with H{sub 2}O{sub 2}based on the polydispersity index (PDI) derived from the calculation of weight average molecular weight over number average molecular weight (Mw/Mn). Mechanism of chitosan radiation degradation with and without hydrogen peroxide was also discussed in this paper. Structure of degraded products was characterized with Fourier-transform infrared spectra. The degree of deacetylation (DDA) values of the samples was determined by acid-base titration. Solubility test results showed that, chitosan powder even at low Mw was insoluble in water even at low pH water. Chitosan as well as irradiated chitosan powder are soluble in strong and weak acid solution. Further discussion on behaviours of radiation degraded chitosan will be elaborated more in this paper.

Degradation of chitosan by gamma ray with presence of hydrogen peroxide

Science.gov (United States)

Mahmud, Maznah; Naziri, Muhammad Ihsan; Yacob, Norzita; Talip, Norhashidah; Abdullah, Zahid

2014-02-01

The radiation degraded chitosan samples were prepared by swelling the chitosan powder in water and exposed for gamma irradiation. The ratio chitosan to water was 1:6 with the presence of hydrogen peroxide (H2O2), 1%-5%. These chitosan-water mixtures were irradiated at 6kGy, which is the lowest irradiation dose that facility can offered. All samples were purified and proceed with characterization. The molecular weight (MW) study was monitored by size exclusion chromatography-multi angle laser light scattering (SEC-MALLS). Results showed that MW of chitosan reduced as the dose increased. Application of H2O2 enhanced the degradation rate of chitosan even at very low irradiation dose. Homogenous degradation also occurred during treatment with H2O2based on the polydispersity index (PDI) derived from the calculation of weight average molecular weight over number average molecular weight (Mw/Mn). Mechanism of chitosan radiation degradation with and without hydrogen peroxide was also discussed in this paper. Structure of degraded products was characterized with Fourier-transform infrared spectra. The degree of deacetylation (DDA) values of the samples was determined by acid-base titration. Solubility test results showed that, chitosan powder even at low Mw was insoluble in water even at low pH water. Chitosan as well as irradiated chitosan powder are soluble in strong and weak acid solution. Further discussion on behaviours of radiation degraded chitosan will be elaborated more in this paper.

Hydrogen peroxide probes directed to different cellular compartments.

OpenAIRE

Mikalai Malinouski; You Zhou; Vsevolod V Belousov; Dolph L Hatfield; Vadim N Gladyshev

2011-01-01

Background Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells. Principal Findings Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular ...

The oxidative dissolution of unirradiated UO2 by hydrogen peroxide as a function of pH

International Nuclear Information System (INIS)

Clarens, F.; Pablo, J. de; Casas, I.; Gimenez, J.; Rovira, M.; Merino, J.; Cera, E.; Bruno, J.; Quinones, J.; Martinez-Esparza, A.

2005-01-01

The dissolution of non-irradiated UO 2 was studied as a function of both pH and hydrogen peroxide concentration (simulating radiolytic generated product). At acidic pH and a relatively low hydrogen peroxide concentration (10 -5 mol dm -3 ), the UO 2 dissolution rate decreases linearly with pH while at alkaline pH the dissolution rate increases linearly with pH. At higher H 2 O 2 concentrations (10 -3 mol dm -3 ) the dissolution rates are lower than the ones at 10 -5 mol dm -3 H 2 O 2 , which has been attributed to the precipitation at these conditions of studtite (UO 4 . 4H 2 O, which was identified by X-ray diffraction), together with the possibility of hydrogen peroxide decomposition. In the literature, spent fuel dissolution rates determined in the absence of carbonate fall in the H 2 O 2 concentration range 5 x 10 -7 - 5 x 10 -5 mol dm -3 according to our results, which is in agreement with H 2 O 2 concentrations determined in spent fuel leaching experiments

Antioxidant activity, phenolic content, and peroxide value of essential oil and extracts of some medicinal and aromatic plants used as condiments and herbal teas in Turkey.

Science.gov (United States)

Ozcan, Mehmet Musa; Erel, Ozcan; Herken, Emine Etöz

2009-02-01

The antioxidant activity, total peroxide values, and total phenol contents of several medicinal and aromatic plant essential oil and extracts from Turkey were examined. Total phenolic contents were determined using a spectrophotometric technique and calculated as gallic acid equivalents. Total antioxidant activity of essential oil and extracts varied from 0.6853 to 1.3113 and 0.3189 to 0.6119 micromol of Trolox equivalents/g, respectively. The total phenolic content of essential oil ranged from 0.0871 to 0.5919 mg of gallic acid/g dry weight. However, the total phenolic contents of extracts were found to be higher compared with those of essential oils. The amount of total peroxide values of oils varied from 7.31 (pickling herb) to 58.23 (bitter fennel flower) mumol of H(2)O(2)/g. As a result, it is shown that medicinal plant derivatives such as extract and essential oils can be useful as a potential source of total phenol, peroxide, and antioxidant capacity for protection of processed foods.

Salicylic Acid Alters Antioxidant and Phenolics Metabolism in ...

African Journals Online (AJOL)

Key words: Antioxidant enzymes; Catharanthus roseus; indole alkaloids; phenolic metabolism; salicylic acid; salinity stress. Abbreviations: CAT - catalase; Chl - chlorophyll; Car - carotenoids; DTNB - 5,5-dithiobis-2-nitrobenzoic acid; GR - glutathione reductase; GST - Glutathione-S-transferase; H2O2 - hydrogen peroxide; ...

Performance, carcass traits, meat quality and amino acid profile of different Japanese quails strains.

Science.gov (United States)

Nasr, Mohammed A F; Ali, El-Shimaa M R; Hussein, Mohamed A

2017-12-01

Poultry production is considered one of the prospective opportunities to accomplish sustainable and quick production of superior protein to challenge the growing mandate for animal protein. Therefore, this study was aimed to explore the difference on growth performance, carcass traits, meat quality and amino acid profile of different Japanese quails strains. A total of 480 quail chicks of four different plumage colors (120 of each white, golden, gray and brown) were collected after hatching. At 6 week of age, birds were stunned and decapitated to determine the physical meat quality, thiobarbituric acid reactive substances and amino acid profile. White quails had the highest weight of slaughter, carcass, dressing, carcass yield, liver, gizzard, heart and spleen (197.27 g, 169.27 g, 91%, 82%, 6.63 g, 6.53 g, 2.27 g and 0.40 g, respectively). Also, they had the highest Ph U , lightness, yellowness and water holding capacity with the lowest level of redness, cooking losses and thiobarbituric acid in pectoral (6.28, 46.40, 12,46, 22.17, 9.20, 19.21 and 0.44, respectively) and thigh muscles (6.37, 42.30, 11.51, 26.01, 10.12 and 0.93, respectively). Moreover, they possessed the highest level of all essential (11.68 and 10.16 g/100 g protein in pectoral and thigh muscles, respectively) and non essential amino acids (13.27 and 12.54 g/100 g protein in pectoral and thigh muscles, respectively). Therefore, the current study revealed that white quails had the heaviest body weight with the best carcass traits and meat quality.

UVA-induced immune suppression in human skin: protective effect of vitamin E in human epidermal cells in vitro

International Nuclear Information System (INIS)

Clement-Lacroix, P.; Michel, L.; Moysan, A.; Morliere, P.; Dubertret, L.

1996-01-01

UVA (320-400 nm) radiation damage to membranes, proteins, DNA and other cellular targets is predominantly related to oxidative processes. In the present study, we demonstrated that cutaneous UVA-induced immunosuppression can be related, at least in part, to the appearance of these oxidative processes. The UVA-induced oxidative processes in freshly isolated epidermal cells were monitored by measuring the thiobarbituric acid reactive substances (TBARS) as an index of peroxidation. The in vitro immunosuppressive effects of UVA were demonstrated by measuring the allogenic lymphocyte proliferation induced by epidermal cells or purified Langerhans cells in the mixed epidermal cell-lymphocyte reaction (MECLR). In addition, the effects of a potent antioxidant (vitamin E) on these two UVA-induced processes were analysed. (author)

Proteomics of desiccation tolerance during development and germination of maize embryos

DEFF Research Database (Denmark)

Huang, Hui; Møller, Ian Max; Song, Song-Quan

2012-01-01

Maize seeds were used to identify the key embryo proteins involved in desiccation tolerance during development and germination. Immature maize embryos (28N) during development and mature embryos imbibed for 72 h (72HN) are desiccation sensitive. Mature maize embryos (52N) during development...... pattern. We infer that these eleven proteins are involved in seed desiccation tolerance. We conclude that desiccation-tolerant embryos make more economical use of their resources to accumulate protective molecules and antioxidant systems to deal with maturation drying and desiccation treatment........ are desiccation tolerant. Thiobarbituric acid reactive substance and hydrogen peroxide contents decreased and increased with acquisition and loss of desiccation tolerance, respectively. A total of 111 protein spots changed significantly (1.5 fold increase/decrease) in desiccation-tolerant and -sensitive embryos...

Lipid analyses of fumigated vs irradiated raw and roasted almonds

International Nuclear Information System (INIS)

Uthman, R.S.; Toma, R.B.; Garcia, R.; Medora, N.P.; Cunningham, S.

1998-01-01

The purpose of this study was to compare the effects of propylene oxide (PO) and irradiation treatments on the lipid analyses of raw and roasted almonds. Eight kilograms each of raw and roasted almonds were divided into four batches (2 kg each). Three of the batches were subjected to PO treatment or irradiation treatment with a dose of 6, 10·5 kGy. The untreated batch served as control samples, they were taken from all the batches at three consecutive times during storage (day 0, 8 weeks and 16 weeks) and analysed for iodine number, peroxide value and 2-thiobarbituric acid number. Overall, irradiated almonds incurred a higher variation in lipid stability than PO tested almonds while roasted almonds incurred a higher variation than raw almonds

Radioimmunoanalysis of the immune response and tissue lipoperoxidation of rats for low doses contaminated with tritiated water

International Nuclear Information System (INIS)

Bejan, A.; Turcu, Gr.

1996-01-01

The paper presents the evaluation of the humoral immune response and liver and kidney lipoperoxidation on rats acutely and chronically contaminated with low doses of tritiated water (HTO). The contamination doses for both situations were 0.5 cSv, 5 cSv and 10 cSv. By humoral immune response analysis we mean the measurement, through a radioimmunoanalysis (RIA) method, of the two intrinsic parameters of an antiserum, that is, the mean antibodies concentration and the mean antibodies affinity constant. We followed the liver and kidney lipidic peroxidation through malondialdehyde (MDA) formation assayed by the thiobarbituric acid (TBA) reaction. The humoral immune response and lipoperoxidation have been compared with the response of an uncontaminated group by the Student t test. (author). 17 refs., 2 tabs

Hydrogen Peroxide Cycling in High-Temperature Acidic Geothermal Springs and Potential Implications for Oxidative Stress Response

Directory of Open Access Journals (Sweden)

Margaux M. Meslé

2017-05-01

Full Text Available Hydrogen peroxide (H2O2, superoxide (O2•-, and hydroxyl radicals (OH• are produced in natural waters via ultraviolet (UV light-induced reactions between dissolved oxygen (O2 and organic carbon, and further reaction of H2O2 and Fe(II (i.e., Fenton chemistry. The temporal and spatial dynamics of H2O2 and other dissolved compounds [Fe(II, Fe(III, H2S, O2] were measured during a diel cycle (dark/light in surface waters of three acidic geothermal springs (Beowulf Spring, One Hundred Springs Plain, and Echinus Geyser Spring; pH = 3–3.5, T = 68–80°C in Norris Geyser Basin, Yellowstone National Park. In situ analyses showed that H2O2 concentrations were lowest (ca. 1 μM in geothermal source waters containing high dissolved sulfide (and where oxygen was below detection and increased by 2-fold (ca. 2–3 μM in oxygenated waters corresponding to Fe(III-oxide mat formation down the water channel. Small increases in dissolved oxygen and H2O2 were observed during peak photon flux, but not consistently across all springs sampled. Iron-oxide microbial mats were sampled for molecular analysis of ROS gene expression in two primary autotrophs of acidic Fe(III-oxide mat ecosystems: Metallosphaera yellowstonensis (Archaea and Hydrogenobaculum sp. (Bacteria. Expression (RT-qPCR assays of specific stress-response genes (e.g., superoxide dismutase, peroxidases of the primary autotrophs were used to evaluate possible changes in transcription across temporal, spatial, and/or seasonal samples. Data presented here documented the presence of H2O2 and general correlation with dissolved oxygen. Moreover, two dominant microbial populations expressed ROS response genes throughout the day, but showed less expression of key genes during peak sunlight. Oxidative stress response genes (especially external peroxidases were highly-expressed in microorganisms within Fe(III-oxide mat communities, suggesting a significant role for these proteins during survival and growth in

UV photodissociation spectroscopy of oxidized undecylenic acid films.

Science.gov (United States)

Gomez, Anthony L; Park, Jiho; Walser, Maggie L; Lin, Ao; Nizkorodov, Sergey A

2006-03-16

Oxidation of thin multilayered films of undecylenic (10-undecenoic) acid by gaseous ozone was investigated using a combination of spectroscopic and mass spectrometric techniques. The UV absorption spectrum of the oxidized undecylenic acid film is significantly red-shifted compared to that of the initial film. Photolysis of the oxidized film in the tropospheric actinic region (lambda > 295 nm) readily produces formaldehyde and formic acid as gas-phase products. Photodissociation action spectra of the oxidized film suggest that organic peroxides are responsible for the observed photochemical activity. The presence of peroxides is confirmed by mass-spectrometric analysis of the oxidized sample and an iodometric test. Significant polymerization resulting from secondary reactions of Criegee radicals during ozonolysis of the film is observed. The data strongly imply the importance of photochemistry in aging of atmospheric organic aerosol particles.

The Effectiveness of Rambutan (Nephelium lappaceum L. Extract in Stabilization of Sunflower Oil under Accelerated Conditions

Directory of Open Access Journals (Sweden)

Winne Sia Chiaw Mei

2014-05-01

Full Text Available The oxidative properties of sunflower oil supplemented with rambutan extract, (crude extract and its fractionated fraction, SF II in comparison with synthetic antioxidant were investigated. The supplemented sunflower oils were stored under accelerated conditions for 24 days at 60 °C. For every 6-day interval, the oxidative properties of the supplemented sunflower oil were evaluated based on the following tests, namely peroxide value, p-anisidine value, Thiobarbituric Acid Reactive Substances (TBARS assay, iodine value and free fatty acids. The total oxidation (TOTOX values were also calculated based on the peroxide values and p-anisidine values. Rambutan extract is a potential source of antioxidant. The oxidative activities of the extracts at all concentrations were significantly (p < 0.05 higher than the control. Generally, the partially fractionated fraction was more effective than the crude extract. With a 2-year storage period at ambient temperature, the fractionated fraction of the extract, SF II at 300 ppm, was observed to work more effectively than the synthetic antioxidant, t-Tocopherol, and it possessed a protective effect comparable with butylatedhydrioxynanisole (BHA. Therefore, rambutan extract could be used as a potential alternative source of antioxidant in the oil industry or other fat-based products to delay lipid oxidation.