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Effective Antioxidants (effective + antioxidant)
Selected AbstractsFerulic acid, a natural protector against carbon tetrachloride-induced toxicityFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 4 2005M. Srinivasan Abstract The present work is aimed at evaluating the protective effect of ferulic acid (FA), a naturally occurring phenolic compound on CCl4 induced toxicity. The activities of liver markers (alanine transaminase, aspartate transaminase, alkaline phosphatase, , -glutamyl transferase), lipid peroxidative index (thiobarbituric acid-reactive substances, hydroperoxides, nitric oxide, protein carbonyl content), the antioxidant status (superoxide dismutase, catalase, glutathione peroxidase and reduced glutathione) were used as biomarkers to monitor the protective role of FA. The liver marker enzymes in plasma and lipid peroxidative index in liver and kidney were increased in CCl4 -treated groups, which were decreased significantly on treatment with FA. The antioxidants, which were depleted in CCl4 -treated groups, were improved significantly by FA treatment. Administration of FA to normal rats did not produce any harmful effects. Thus our results show that FA is an effective antioxidant without any side-effects and may be a great gain in the current search for natural therapy. [source] Detoxification and antioxidant effects of curcumin in rats experimentally exposed to mercuryJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2010Rakhi Agarwal Abstract Curcumin, a safe nutritional component and a highly promising natural antioxidant with a wide spectrum of biological functions, has been examined in several metal toxicity studies, but its role in protection against mercury toxicity has not been investigated. Therefore, the detoxification and antioxidant effects of curcumin were examined to determine its prophylactic/therapeutic role in rats experimentally exposed to mercury (in the from of mercuric chloride-HgCl2, 12,µmol,kg,1 b.w. single intraperitoneal injection). Curcumin treatment (80,mg,kg,1 b.w. daily for 3 days, orally) was found to have a protective effect on mercury-induced oxidative stress parameters, namely, lipid peroxidation and glutathione levels and superoxide dismutase, glutathione peroxidase and catalase activities in the liver, kidney and brain. Curcumin treatment was also effective for reversing mercury-induced serum biochemical changes, which are the markers of liver and kidney injury. Mercury concentration in the tissues was also decreased by the pre/post-treatment with curcumin. However, histopathological alterations in the liver and kidney were not reversed by curcumin treatment. Mercury exposure resulted in the induction of metallothionein (MT) mRNA expressions in the liver and kidney. Metallothionein mRNA expression levels were found to decrease after the pre-treatment with curcumin, whereas post-treatment with curcumin further increased MT mRNA expression levels. Our findings suggest that curcumin pretreatment has a protective effect and that curcumin can be used as a therapeutic agent in mercury intoxication. The study indicates that curcumin, an effective antioxidant, may have a protective effect through its routine dietary intake against mercury exposure. [source] Oxidative stress of the newborn in the pre- and postnatal period and the clinical utility of melatoninJOURNAL OF PINEAL RESEARCH, Issue 2 2009Eloisa Gitto Abstract:, Newborns, and especially those delivered preterm, are probably more prone to oxidative stress than individuals later in life. Also during pregnancy, increased oxygen demand augments the rate of production of reactive oxygen species (ROS) and women, even with normal pregnancies, experience elevated oxidative stress and lipid peroxidation compared with nonpregnant women. Also, there appears to be an increase in ROS generation in the placenta of pre-eclamptic women. In comparison with healthy adults, newborn infants have lower levels of plasma antioxidants such as vitamin E, ,-carotene, and sulphydryl groups, lower levels of plasma metal binding proteins including ceruloplasmin and transferrin, and reduced activity of erythrocyte superoxide dismutase. This review summarizes conditions of newborns where there is elevated oxidative stress. Included in this group of conditions is asphyxia, respiratory distress syndrome and sepsis and the review also summarizes the literature related to clinical trials of antioxidant therapies and of melatonin, a highly effective antioxidant and free radical scavenger. The authors document there is general agreement that short-term melatonin therapy may be highly effective and that it has a remarkably benign safety profile, even when neonates are treated with pharmacological doses. Significant complications with long-term melatonin therapy in children and adults also have not been reported. None of the animal studies of maternal melatonin treatment or in postnatal life have shown any treatment-related side effects. The authors conclude that treatment with melatonin might result in a wide range of health benefits, improved quality of life and reduced healthcare costs and may help reduce complications in the neonatal period. [source] Effects of testosterone and vitamin E on the antioxidant system in rabbit testisANDROLOGIA, Issue 5 2004N. Aydilek Summary. The aim of the study was to investigate the effects of testosterone propionate and vitamin E on the antioxidant system in the testis. Thirty-two male New Zealand White rabbits were randomly divided into four groups. The first group was used as control. The second group was injected with testosterone propionate, the third group vitamin E and the fourth group vitamin E and testosterone propionate combination. All treatments were carried out during 6 weeks and oxidative parameters were evaluated in homogenized testicular tissue. The levels of vitamin E and the activity of glutathione peroxidase were lower (P < 0.05) in the testosterone group than in controls. However, vitamin C and malondialdehyde levels were higher (P < 0.05) in this group than in controls. The levels of reduced glutathione, , -carotene, vitamin C and E increased, but malondialdehyde levels decreased in the vitamin E group, when compared with controls (P < 0.05). Vitamin E and , -carotene levels were significantly higher (P < 0.05) in the combination group than in testosterone group. However, MDA levels were lower (P < 0.05) in combination group than in the testosterone group. In conclusion, administration of testosterone propionate led to a significant elevation of oxidative stress. Vitamin E is quite an effective antioxidant which protects rabbit testis against lipid peroxidation, and, testosterone-induced lipid peroxidation could be improved by additional vitamin E treatment. [source] Chlorophyll Catabolites , Chemical and Structural Footprints of a Fascinating Biological Phenomenon,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 1 2009Simone Moser Abstract Twenty years ago, the molecular basis for the seasonal disappearance of chlorophyll was still enigmatic. In the meantime, our knowledge on chlorophyll breakdown has grown considerably. As outlined here, it has been possible to decipher the basic transformations involved in natural chlorophyll breakdown by identification of chlorophyll catabolites in higher plants, and with the help of the synthesis of (putative) catabolic intermediates. In vascular plants, chlorophyll breakdown typically converts the green plant pigments efficiently into colorless and non-fluorescent tetrapyrroles. It involves colored intermediates only fleetingly and in an (elusive) enzyme-bound form. The non-fluorescent chlorophyll catabolites accumulate in the vacuoles of degreened leaves and are considered the products, primarily, of a detoxification process. However, they are effective antioxidants, and may thus also have physiologically beneficial chemical properties.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Maternal carotenoid supplementation does not affect breeding performance in the Great Tit (Parus major)FUNCTIONAL ECOLOGY, Issue 4 2007VLADIMĶR REME Summary 1Carotenoids are micronutrients with many beneficial health-related effects. They are effective antioxidants and stimulants of the immune system. Carotenoids cannot be synthesized in animals and must be obtained from food. As such, they may limit reproductive output and performance, and on the proximate level mediate reproductive trade-offs. 2We studied carotenoid limitation in wild Great Tits (Parus major) by supplementing prelaying and laying females with lutein, the most abundant carotenoid in this species. We followed the effects of this supplementation on egg yolk carotenoid composition, and offspring and parental performance. 3Females transferred the supplemented lutein into egg yolks, increasing lutein concentration to the upper limit of naturally occurring concentrations in control pairs. Concentrations of zeaxanthin, ,-carotene and ,-carotene did not differ between supplemented and control pairs. 4Effects on offspring and parental performance were generally absent or weak. There were no effects on timing of laying, clutch size, hatching success, nestling survival, nestling mass (day 6 and 14), tarsus length or T-cell mediated immune response. Males on supplemented nests fed their young more than those on control nests. There was no positive effect on female feeding or mass. 5Negligible effects of lutein supplementation on offspring and parental performance might be explained by high natural abundance of carotenoids or other antioxidants, where additional carotenoids bear no strong advantage to the birds. Additionally, conflicting results of different studies may be explained by species-specific features of their life-histories. [source] Comparison of potential protective effects of melatonin, indole-3-propionic acid, and propylthiouracil against lipid peroxidation caused by potassium bromate in the thyroid glandJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2005Malgorzata Karbownik Abstract Potassium bromate (KBrO3) is a prooxidant and carcinogen, inducing thyroid tumors. Melatonin and indole-3-propionic acid (IPA) are effective antioxidants. Some antioxidative effects of propylothiouracil (PTU),a thyrostatic drug,have been found. The aim of the study was to compare protective effects of melatonin, IPA, and PTU against lipid peroxidation in the thyroids, collected from rats treated with KBrO3, and in homogenates of porcine thyroids, incubated in the presence of KBrO3. 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). Homogenates of porcine thyroids were incubated for 30 min in the presence of KBrO3 (5 mM) plus one of the antioxidants: melatonin (0.01, 0.1, 0.5, 1.0, 5.0, 7.5 mM), or IPA (0.01, 0.1, 0.5, 1.0, 5.0, 7.5, 10.0 mM), or PTU (0.01, 0.1, 0.5, 1.0, 5.0, 7.5, 10.0 mM). The level of lipid peroxidation products (MDA,+,4-HDA) was measured spectrophotometrically in thyroid homogenates. In vivo pretreatment with either melatonin or with IPA or with PTU decreased lipid peroxidation caused by KBrO3,injections in rat thyroid gland. Under in vitro conditions, PTU (5.0, 7.5, and 10.0 mM), but neither melatonin nor IPA, reduced KBrO3 -related lipid peroxidation in the homogenates of porcine thyroids. In conclusion, melatonin and IPA may be of great value as protective agents under conditions of exposure to KBrO3. © 2005 Wiley-Liss, Inc. [source] Effect of Antioxidants on the Production of Off-Odor Volatiles and Lipid Oxidation in Irradiated Turkey Breast Meat and Meat HomogenatesJOURNAL OF FOOD SCIENCE, Issue 5 2003E.J. Lee ABSTRACT The addition of gallate, sesamol, trolox, and tocopherol was effective, but sesamol, sesamol + tocopherol, and gallate + tocopherol were among the most effective antioxidants in reducing thiobarbituric acid reactive substances, volatile production, and off-odor intensity in turkey breast homogenates. Also, these 3 antioxidant treatments were effective in controlling lipid oxidation and off-odor intensity in both vacuum and aerobically packaged patties. However, aerobic packaging was better than antioxidant treatments in reducing off-odor intensity of irradiated turkey patties. Antioxidants had no effect on redness, but increased lightness and yellowness of irradiated turkey breast. It was concluded that a combination of antioxidant and aerobic packaging was more useful than antioxidant and vacuum packaging in controlling off-odor problems in irradiated raw turkey meat. [source] The Efficiency of TBHQ, ,-carotene, Citric Acid, and Tinuvin 234® on the Sensory Stability of Soybean Oil Packaged in PET BottlesJOURNAL OF FOOD SCIENCE, Issue 1 2003H.M.C. de Azeredo ABSTRACT: The use of plastic packaging for oils permits exposure to light, increasing oxidation. The goal of this work was to maximize sensory stability of soybean oil packaged in PET bottles. A central composite design was used to combine different levels of TBHQ, ,-carotene, and citric acid, added to oil, and Tinuvin 234®, added to bottles. After 6 mo of storage, the oxidation degree was assessed by sensory and peroxide tests. TBHQ and Tinuvin 234 were the most effective antioxidants, and the minimum concentrations required to keep a reasonable stability during storage were: 120 ppm of TBHQ; 7 ppm of ,-carotene; 15 ppm of citric acid and 0.1% of Tinuvin 234. [source] Antioxidant activity of peptide fractions derived from cottonseed protein hydrolysateJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2010Dandan Gao Abstract BACKGROUND: Cottonseed protein is widely regarded as a potential source of nutrients for humans and animals, but it is mainly used as forage in China. In the present study, Neutrase was employed to hydrolyse cottonseed protein to produce a hydrolysate with antioxidant activity suitable for conversion to high-value products. The antioxidant potential of the cottonseed protein hydrolysate (CPH) and its fractions was investigated using different in vitro methods. Furthermore, the amino acid composition of the CPH fractions was determined to evaluate the relationship between antioxidant activity and amino acid composition. RESULTS: The CPH prepared using Neutrase was separated into four fractions (I, II, III and IV) by gel filtration on Sephadex G-25. All fractions were effective antioxidants, with fraction III (0.8,1.2 kDa) showing the strongest activity. The amino acid analysis showed that fraction III also had the highest total amino acid content (616.8 g kg,1 protein) and was rich in Phe, His, Pro, Met, Ile and Cys compared with the other fractions. CONCLUSION: The results showed that the hydrolysate derived from cottonseed protein, particularly fraction III, could be a natural antioxidant source suitable for use as a food additive. Copyright © 2010 Society of Chemical Industry [source] Berry anthocyanins: isolation, identification and antioxidant activities,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2003Marja P Kähkönen Abstract Anthocyanins from bilberry, blackcurrant and cowberry were isolated for antioxidant evaluation. Individual compounds were identified and quantified using HPLC and HPLC/ESI,MS techniques. Antioxidant and radical-scavenging capacities of the isolates were studied in emulsified methyl linoleate and human low-density lipoprotein (LDL) in vitro and in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) test. The total anthocyanin contents in the phenolic extracts of bilberry, blackcurrant and cowberry were 6000, 2360 and 680 mg kg,1 fresh weight respectively. There were four dominant compounds in blackcurrant (glucosides and rutinosides of cyanidin and delphinidin), three in cowberry (monoglycosides of cyanidin) and 15 in bilberry (monoglycosides of cyanidin, delphinidin, malvidin, peonidin and petunidin). Quantification as cyanidin-3-glucoside equivalents gave markedly lower results regarding the total anthocyanin concentration and the content of individual delphinidin and malvidin compounds compared with quantification based on corresponding standard compounds. Berry anthocyanins were highly active radical scavengers in the DPPH test and effective antioxidants in emulsion and human LDL. Copyright © 2003 Society of Chemical Industry [source] The antioxidant activity and stability of the phenolic fraction of green olives and extra virgin olive oilJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2001Turkan Keceli Abstract The antioxidant activity of phenolic extracts from olives and olive oil has been assessed by scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and by studying the effects on the stability of stripped olive oil in the absence and presence of ferric chloride. The olive extracts contained a much higher concentration (1940,5800,mg,kg,1) of phenolic components than the olive oil extract (180,mg,kg,1). Some olive extracts were more effective than the olive oil extract in scavenging DPPH radicals, but the three varieties of olives examined showed relatively large differences in both polyphenol concentration and antioxidant activity of extracts. ,-Tocopherol and extracts from both olives and olive oil were effective antioxidants in stripped olive oil at 60,°C. Ferric chloride reduced the stability of stripped olive oil, but the olive extract studied was significantly more effective as an antioxidant in the presence of the metal salt than the olive oil extract or ,-tocopherol. Ferric ions catalysed the oxidation of caffeic acid, oleuropein and phenolic components of the olive and olive oil extracts in aqueous solution (pH 5.4). The olive extract oxidised more rapidly than the olive oil extract in aqueous solution. © 2001 Society of Chemical Industry [source] | ||||||||||||||||