Antioxidative Properties (antioxidative + property)

Distribution by Scientific Domains


Selected Abstracts


Carbon Monoxide has Antioxidative Properties in the Liver Involving p38 MAP Kinase Pathway in a Murine Model of Systemic Inflammation

MICROCIRCULATION, Issue 7 2010
JÜRGEN BRUGGER
Please cite this paper as: Brugger, Schick, Brock, Baumann, Muellenbach, Roewer and Wunder (2010). Carbon Monoxide has Antioxidative Properties in the Liver Involving p38 MAP Kinase Pathway in a Murine Model of Systemic Inflammation. Microcirculation17(7), 504,513. Abstract Objective:, Reactive oxygen species (ROS) are important in the hepatocellular injury process during a systemic inflammation. We examined the role of carbon monoxide (CO) on the hepatic generation of ROS with in-vivo and in-vitro models of systemic inflammation. Methods:, Using a murine model of bilateral hindlimb ischemia-reperfusion (I/R) we examined the effect of CO treatment on hepatic ROS formation, oxidative status, and cell injury. Cultured HUVEC were used to investigate intracellular pathways. Results:, CO treatment reduced hepatic lipid peroxidation, re-established total hepatic glutathione and glutathione disulfide (GSH/GSSG) levels and reduced hepatocellular injury. Inhibition of heme oxygenase (HO) during treatment with CO during hindlimb I/R failed to alter the antioxidant qualities provided by CO. The production of ROS after tumor necrosis factor-, (TNF-,) stimulation in HUVEC was diminished after exposure to CO. Treatment with CO during HO inhibition reduced both ROS formation and cell injury. Inhibiting the p38 MAPK (mitogen-activated protein kinase) pathway with pyridinyl imidazol (SB203580) revealed that the antioxidant potential of CO involved the activation of p38 MAPK. Conclusions:, CO has direct antioxidant potential independently of any HO activity during systemic inflammation. The antioxidant effects afforded by CO involve the activation of the p38 MAPK pathway. [source]


Antioxidative ability of native and thermized sour whey in oxidation-catalysed model systems,

INTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2007
JINHAN SHON
Antioxidative properties of sour (cottage) were evaluated with (thermized) and without (native) heat treatment (80°C for 30 min). A model system comprising a Tween 20 stabilized peanut oil in phosphate buffer (pH 7.0) emulsion containing lipid oxidation catalysts, FeCl3, H2O2 and ascorbate was used. Native sour whey powder (SWP) was significantly better than thermized whey in terms of limiting the formation of thiobarbituric acid-reactive substances and peroxide value. Antioxidative ability was best at pH 3.0 and decreased with increasing pH. SWP (20%, w/v) was significantly better than all commonly used antioxidants tested after 96 h of incubation at 40°C. [source]


PHENOLIC COMPOUND CONTENT, ANTIOXIDANT AND RADICAL-SCAVENGING PROPERTIES OF METHANOLIC EXTRACTS FROM THE SEED COAT OF CERTAIN THAI TAMARIND CULTIVARS

JOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2010
MANEEWAN SUKSOMTIP
Methanolic extracts from the seed coats of five major tamarinds (Srichomphu, Sithong-nak, Sithong-bao, Priao-yak and Khanti) cultivated in Thailand were investigated for their content of phenolic compounds and their antioxidative properties. Antioxidative properties were evaluated by various different methods: scavenging effect on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical, anti-lipid peroxidation and reducing power assay. The phenolic compound contents were determined by spectrophotometric methods. Extract of Priao-yak with the highest tannin content showed the strongest reducing power, while extract of Khanti with the highest proanthocyanidin content revealed high scavenging ability on both DPPH and hydroxyl radicals. Stronger antioxidative activity measured by most assays was noted for the extract of Sithong-bao with a high content of total phenols, proanthocyanidin and tannins. The results suggest that specific phenolic constituents in the extract could be responsible for the different antioxidant properties observed in different cultivars. Furthermore, seed coat extract of Sithong-bao may be a potential source of natural antioxidant to be developed into nutraceuticals. PRACTICAL APPLICATIONS Components of Tamarindus indica L., a tree indigenous to India and South-East Asia, have long been used as a spice, food component and traditional medicine. According To traditional medicine, the tamarind pulp is used as a digestive, carminative, laxative, expectorant and blood tonic; the seeds are used as an anthelmintic, antidiarrheal and emetic. In addition, the seed coat is used to treat burns and aid wound healing as well as as an antidysenteric. Recent studies have demonstrated polyphenolic constituents with more potent antioxidant and anti-inflammatory activities of T. indica seed coat extract. Therefore, seed coat extracts of T. indica have economic potential for development into health promotion products as well as natural preservatives to increase the shelf life of food by preventing lipid peroxidation. [source]


Antioxidative properties of lycopene and other carotenoids from tomatoes: Synergistic effects

BIOFACTORS, Issue 1-4 2004
John Shi
Lycopene is the major carotenoid in tomatoes. Tomatoes contain a matrix of many bioactive components, including vitamin C, vitamin E, other carotenoids (a-, ,-, ,- carotene, lutein), and flavonoids. Their synergistic interactions, when used in combination, may be responsible for the observed beneficial effects of tomato-based products. This study investigated the synergistic antioxidant activity of lycopene in combination with ,-carotene, vitamin E, and lutein. A liposome system was used to test the synergistic antioxidant activity. The carotenoid mixtures were more efficient in protecting liposome from oxidation than the individual carotenoid. Mixtures of lycopene and vitamin E appear to have the greatest synergistic antioxidant activity. [source]


Antioxidant capacity of rapeseed meal and rapeseed oils enriched with meal extract

EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2010
Aleksandra Szyd, owska-Czerniak
Abstract Response surface methodology (RSM) was used to evaluate the quantitative effects of two independent variables: solvent polarity and temperature of the extraction process on the antioxidant capacity (AC) and total phenolics content (TPC) in meal rapeseed extracts. The mean AC and TPC results for meal ranged between 1181,9974,µmol TE/100,g and 73.8,814,mg sinapic acid/100,g of meal. The experimental results of AC and TPC were close to the predicted values calculated from the polynomial response surface models equations (R2,=,0.9758 and 0.9603, respectively). The effect of solvent polarity on AC and TPC in the examined extracts was about 3.6 and 2.6 times greater, respectively, than the effect of processing temperature. The predicted optimum solvent polarity of ,,=,78.3 and 63.8, and temperature of 89.4 and 74.2°C resulted in an AC of 10,014,µmol TE/100,g and TPC of 863,mg SAE/100,g meal, respectively. The phenolic profile of rapeseed meal was determined by an HPLC method. The main phenolics in rapeseed meal were sinapine and sinapic acid. Refined rapeseed oils were fortified with an extract , rich in polyphenols , obtained from rapeseed meal. The supplemented rapeseed oil had higher AC and TPC than the refined oil without addition of meal extracts. However, AC and TPC in the enriched oils decreased during storage. The TPC in the studied meal extracts and rapeseed oils correlated significantly (p<0.0000001) positively with their AC (R2,=,0.9387). Practical applications: Many bioactive compounds extracted from rapeseed meal provide health benefits and have antioxidative properties. Therefore, it seems worth to consider the application of antioxidants extracted from the rapeseed meal for the production of rapeseed oils with potent AC. Moreover, antioxidants extracted from the rapeseed meal were added to refined rapeseed oil in order to enhance its AC. AC was then tested by FRAP assay. FRAP method is based on the reduction of the ferric tripyridyltriazine (Fe3+ -TPTZ) complex to the ferrous tripyridyltriazine (Fe2+ -TPTZ), and it is simple, fast, low cost, and robust method. FRAP method does not require specialized equipment and can be performed using automated, semi-automatic, or manual methods. Therefore the proposed FRAP method can be employed by the fat industry laboratories to asses the AC of rapeseed oils and meal. [source]


Stem Cell Aligned Growth Induced by CeO2 Nanoparticles in PLGA Scaffolds with Improved Bioactivity for Regenerative Medicine

ADVANCED FUNCTIONAL MATERIALS, Issue 10 2010
Corrado Mandoli
Abstract Hybrid 2D polymeric,ceramic biosupports are fabricated by mixing a nanostructured CeO2 powder with 85:15 poly(D,L -lactic- co -glycolic acid) (PLGA)/dichloromethane solutions at specific concentrations, followed by solvent casting onto pre-patterned molds. The mold patterning allows the orientation of ceramic nanoparticles into parallel lines within the composite scaffold. The ability of the produced films to host and address cell growth is evaluated after 1, 3, and 6 days of culturing with murine derived cardiac and mesenchymal stem cells (CSCs and MSCs), and compared with PLGA films without ceramics and loaded with nanostructured TiO2. Aligned cell growth is observed only for scaffolds that incorporate oriented ceramic nanoparticles, attributed to the nanoceramic ability to modulate the roughness pitch, thus improving cell sensitivity towards the host surface features. Better CSC and MSC proliferative activity is observed for CeO2 composites with respect to either TiO2 -added or unfilled PLGA films. This evidence may be related to the nanostructured CeO2 antioxidative properties. [source]


PHENOLIC COMPOUND CONTENT, ANTIOXIDANT AND RADICAL-SCAVENGING PROPERTIES OF METHANOLIC EXTRACTS FROM THE SEED COAT OF CERTAIN THAI TAMARIND CULTIVARS

JOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2010
MANEEWAN SUKSOMTIP
Methanolic extracts from the seed coats of five major tamarinds (Srichomphu, Sithong-nak, Sithong-bao, Priao-yak and Khanti) cultivated in Thailand were investigated for their content of phenolic compounds and their antioxidative properties. Antioxidative properties were evaluated by various different methods: scavenging effect on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical, anti-lipid peroxidation and reducing power assay. The phenolic compound contents were determined by spectrophotometric methods. Extract of Priao-yak with the highest tannin content showed the strongest reducing power, while extract of Khanti with the highest proanthocyanidin content revealed high scavenging ability on both DPPH and hydroxyl radicals. Stronger antioxidative activity measured by most assays was noted for the extract of Sithong-bao with a high content of total phenols, proanthocyanidin and tannins. The results suggest that specific phenolic constituents in the extract could be responsible for the different antioxidant properties observed in different cultivars. Furthermore, seed coat extract of Sithong-bao may be a potential source of natural antioxidant to be developed into nutraceuticals. PRACTICAL APPLICATIONS Components of Tamarindus indica L., a tree indigenous to India and South-East Asia, have long been used as a spice, food component and traditional medicine. According To traditional medicine, the tamarind pulp is used as a digestive, carminative, laxative, expectorant and blood tonic; the seeds are used as an anthelmintic, antidiarrheal and emetic. In addition, the seed coat is used to treat burns and aid wound healing as well as as an antidysenteric. Recent studies have demonstrated polyphenolic constituents with more potent antioxidant and anti-inflammatory activities of T. indica seed coat extract. Therefore, seed coat extracts of T. indica have economic potential for development into health promotion products as well as natural preservatives to increase the shelf life of food by preventing lipid peroxidation. [source]


Probing the antioxidative properties of combinations of an organotellurium compound, BHT and thiol in oil

LUBRICATION SCIENCE, Issue 2 2006
David Shanks
Abstract Differential scanning calorimetry experiments with an unsaturated polyolester oil at 190°C showed that an organotellurium compound in combination with a thiol or a sterically hindered phenol (BHT) could act in a synergistic fashion to protect the material from oxidation. Under more realistic conditions for an oil antioxidant (elevated temperature in the presence of oxygen, water and a copper coil; rotating pressure vessel oxidation test) the antioxidant protection offered by the organotellurium/thiol and organotellurium/BHT combinations could not match the protection offered by BHT itself at similar concentrations. In order for the novel antioxidant systems to become useful for protection of oils and fluids, more robust organotellurium compounds must be prepared. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Scavenger activity of Allium psekemense B. Fedtsch

PHYTOTHERAPY RESEARCH, Issue 5 2002
tajner
Abstract In the present study the antioxidative properties of the bulbs, leaves and stalks of Allium psekemense B. Fedtsch were investigated. The activities of antioxidant enzymes (superoxide dismutase, catalase, peroxidase, glutathione peroxidase), quantities of malonyldialdehyde, superoxide and hydroxyl radicals and reduced glutathione and also the content of total flavonoids, chlorophylls a and b, carotenoids, vitamin C and soluble proteins were determined. The results indicate that extracts from all plant organs exhibited antioxidant activity. The highest antioxidant activity was observed in the leaves. Furthermore, the ESR signal of DMPO-OH radical adducts in the presence of the leaf phosphate buffer (pH 7) extract was reduced by 54.3%. Copyright © 2002 John Wiley & Sons, Ltd. [source]


Paraoxonases role in the prevention of cardiovascular diseases

BIOFACTORS, Issue 1 2009
Mira Rosenblat
Abstract Increased oxidative stress is a characteristic of patients with high risk for atherosclerosis development (hypercholesterolemic, hypertensive, diabetic), and the above phenomenon was shown to be associated with attenuated antioxidative status. The increased oxidative stress in atherosclerotic patients is present in their blood, as well as in their arterial wall cells, including macrophages, the hallmark of foam cells formation during early atherogenesis. Serum high density lipoprotein (HDL)-associated paraoxonase 1 (PON1) reduces oxidative stress in lipoproteins, in macrophages, and in the atherosclerotic lesion, whereas paraoxonase 2 (PON2, which is present in tissues, but not in serum) acts as an antioxidant at the cellular and not humoral level. Both PON1 and PON2 protect against atherosclerosis development, and this phenomenon could be related to their antioxidative properties. The use of nutritional antioxidants such as vitamin E, carotenoids (lycopene and ,-carotene), and mainly polyphenols (such as those present in red wine, licorice root ethanolic extract, or in pomegranate) by atherosclerotic animals and also by cardiovascular patients, leads to a reduction in oxidative stress and to the attenuation of atherosclerosis development. These latter phenomena could be related to the nutritional antioxidants-induced increase in HDL PON1 activity (effects on gene expression, on preventing enzyme inactivation, and on increasing PON1 stability through its binding to HDL), as well as an increase in macrophage PON2 activation (at the gene expression level). © 2009 International Union of Biochemistry and Molecular Biology, Inc. [source]


Protective effects of melatonin and indole-3-propionic acid against lipid peroxidation, caused by potassium bromate in the rat kidney

CELL BIOCHEMISTRY AND FUNCTION, Issue 6 2006
gorzata Karbownik
Abstract Potassium bromate (KBrO3) is classified as a carcinogenic agent. KBrO3 induces tumors and prooxidative effects in kidneys. Melatonin is a well known antioxidant and free radical scavenger. Indole-3-propionic acid (IPA), an indole substance, also reveals antioxidative properties. Recently, some antioxidative effects of propylthiouracil (PTU),an antithyroid drug,have been found. The aim of the study was to compare protective effects of melatonin, IPA, and PTU against lipid peroxidation in the kidneys and blood serum and, additionally, in the livers and the lungs, collected from rats, pretreated with KBrO3. Male Wistar rats were administered KBrO3 (110 mg/kg b.w., i.p., on the 10th day of the experiment) and/or melatonin, or IPA (0.0645 mmol/kg b.w., i.p., twice daily, for 10 days), or PTU (0.025% solution in drinking water, for 10 days). The level of lipid peroxidation products,malondialdehyde,+,4-hydroxyalkenals (MDA,+,4-HDA),was measured spectrophotometrically in thyroid homogenates. KBrO3, when injected to rats, significantly increased lipid peroxidation in the kidney homogenates and blood serum, but not in the liver and the lung homogenates. Co-treatment with either melatonin or with IPA, but not with PTU, decreased KBrO3 -induced oxidative damage to lipids in the rat kidneys and serum. In conclusion, melatonin and IPA, which prevent KBrO3 -induced lipid peroxidation in rat kidneys, may be of great value as protective agents under conditions of exposure to KBrO3. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Conversion of the Synthetic Catalase Mimic Precursor TAA-1 into the Active Catalase Mimic in Isolated Hepatocytes

CHEMICAL BIOLOGY & DRUG DESIGN, Issue 5 2009
Ursula Rauen
In previous studies we reported on the catalase-like activity and antioxidative properties of a non-heme Fe(III)-tetraaza[14]annulene complex, 5,4-didehydro-5,9,14,18-tetraaza-di(2,2-dimethyl-[5,6]benzo[1,3]dioxolo)[a,h]cyclotetradecene,Fe(III) chloride (TAA-1/Fe). We proposed that intracellular application of the parent, iron-free tetraaza[14]annulene ligand, TAA-1, as precursor would allow antioxidative defense along two lines, i.e. by chelation of potentially toxic cellular iron ions and, subsequently, by catalase-mimic activity. We here set out to establish whether the active catalase mimic is indeed formed intracellularly when cells are loaded with the ligand. When isolated rat hepatocytes were preloaded with TAA-1, they were protected against iron-induced cell injury and oxidative stress elicited by exposure to the membrane-permeable iron complex Fe(III)/8-hydroxyquinoline. After lysis of the cells, followed by ultrafiltration to remove endogenous catalase, the lysate exhibited catalase-like activity, while lysates of control cells not treated with TAA-1 showed no catalase-like activity. By comparison with authentic TAA-1/Fe, an intracellular formation of 2.0 ± 0.3 ,m of the active catalase mimic in native hepatocytes exposed to TAA-1 and of 6.5 ± 1.0 ,m in hepatocytes exposed to both TAA-1 and iron ions was estimated. The intracellular formation of the active catalase mimic thus renders TAA-1 an attractive compound for protection against iron- and/or hydrogen peroxide-dependent cell injuries. [source]


EFFICACY OF SOUR WHEY AS A SHELF-LIFE ENHANCER: USE IN ANTIOXIDATIVE EDIBLE COATINGS OF CUT VEGETABLES AND FRUIT,

JOURNAL OF FOOD QUALITY, Issue 5 2007
JINHAN SHON
ABSTRACT The effectiveness of edible coatings containing sour whey powder (SWP), compared with soy protein isolate (SPI) and calcium caseinate (CC), in reducing oxidative browning and moisture loss during storage (4C) of cut apples, potatoes, carrots, and onions was investigated. Oxidative discoloration, as determined by the Commission Internationale de I'Eclairage L*a*b* color scale, was significantly reduced (P < 0.05) by treatments over a storage time of 120 min. Loss of lightness was reduced by CC, SPI and SWP coatings. These respectively showed 2.7, 3.3 and 1.5% change of L* value in coated apples as compared with 7.4% in the control. Browning in cut potatoes was significantly reduced from a 145.1% increase in the a* value of the control to 45.9, 37.0 and 30.3% increase for CC, SPI and SWP treatments, respectively. The b* values also reflected the effectiveness of SWP. The moisture barrier effect, tested over a period of 5 days at 4C, was significantly better for the treatments than control. SWP was the best and significantly reduced moisture loss in potatoes and carrots by 40 and 59%, respectively, over control. Cut onions did not show any treatment effect both in terms of off-color development and moisture loss. The reasons for the excellent moisture barrier and antioxidative property of SWP were discussed. PRACTICAL APPLICATIONS Oxidative degradation of fresh fruits and vegetables is a major problem faced by the industry today. Most of the fresh produce is grown in the southwestern part of the country, requiring days of transportation to retail outlets. As the educated consumer is highly health conscious, any effort in extending the shelf life will have to be nonchemical, and preferably natural. Because of small profit margins, the intervention must also be inexpensive. Millions of MT of sour whey, a by-product of cottage whey manufacture, is wasted because of the lack of appropriate food applications. It is natural, nutritious and presently very inexpensive. Our research investigated the possibility of using this by-product as a final wash to enhance the so-called window of freshness of fresh produce and fruit. [source]