Home About us Contact
|
Home About us Contact | ||
|
|
||
Strong Antioxidant Activity (strong + antioxidant_activity)
Selected AbstractsPhysiological effects and active ingredients of Viburnum dilatatum Thunb fruits on oxidative stressBIOFACTORS, Issue 1-4 2004Kunihisa Iwai Abstract The fruit of Viburnum dilatatum Thunb, called gamazumi in Japan, showed the strong antioxidant activities, and its preventive effects on oxidative stress and active ingredients were investigated. Male rats were subjected to water immersion restraint stress for 6 hours, after ingestion of the gamazumi crude extract (GCE) for 2 weeks. The formation of gastric ulcer was reduced, and the lipid peroxidation in plasma and organs also lowered in rats ingested GCE. In the streptozotocin-induced diabetic rats given GCE for 10 weeks, inhibition of lipid peroxidation in plasma, erythrocytes and organs was observed, and the increase of plasma glucose level also lowered. On the other hand, two cyanidin glycosides, two chlorogenic acids and quercetin were identified, and especially cyanidin 3-sambubioside (Cy 3-sam) showed the strong radical scavenging activity. It is suggested that Cy 3-sam is a key compound contributing to the physiological effects of V. dilatatum fruit. [source] Microencapsulation of rosmarinic acid using polycaprolactone and various surfactantsINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 3 2010H.-J. Kim Synopsis Rosmarinic acid (RA) has a number of interesting biological activities, e.g. anti-viral, anti-bacterial, anti-inflammatory and antioxidant. The antioxidant activity of RA is stronger than that of vitamin E. Despite its strong antioxidant activity, it was limited to use in cosmetics because of the low water solubility, discolouration and chemical instability. The purpose of this study was to prepare RA-loaded polycaprolactone (PCL) microspheres using emulsion solvent evaporation method and characterize them with different surfactants used in the formation process. Finally, long-term stability of RA was evaluated in the cosmetic formulation. As a result, PCL microspheres were found to be spherical in shape, with zwitterionic surfactant-PCL particles being the smallest size distribution and highest entrapment efficiency of RA. Emulsions containing RA-loaded PCL microspheres showed a better long-term stability of the RA compared with those containing only RA. These results suggest that RA may be stably and efficiently encapsulated into polycaprolactone microspheres. Résumé Micro encapsulation d'acide rosmarinique utilisant la polycaprolactone et divers surfactants L'acide rosmarinique a un certain nombre d'activités biologiques intéressantes, par exemple antivirales, antibactériennes, anti-inflammatoires et antioxydantes. L'activité antioxydante de l'acide rosmarinique est plus puissante que celle de la vitamine E. Malgré sa forte activité antioxydante, son usage en cosmétique est limité en raison de sa faible solubilité dans l'eau, sa décoloration et son instabilité chimique. Le but de cette étude était de préparer des microsphères de PCL chargées d'acide rosmarinique par la méthode d'émulsification par d'évaporation de solvant et de les caractériser selon les différents surfactants utilisés dans le processus de fabrication. Enfin, la stabilitéà long terme de l'acide rosmarinique a étéévaluée dans la formulation cosmétique. Les microsphères PCL ont été trouvé de forme sphérique, avec les surfactants zwitterioniques, les particules PCL offrent une distribution de petites tailles et une efficacité de piégeage en acide rosmarinique la plus élevée. Les émulsions contenant des microsphères PCL chargées d'acide rosmarinique ont montréà long terme une meilleure stabilité en acide rosmarinique que celles contenant l'acide seul. Ces résultats suggèrent que l'acide rosmarinique peut être encapsulé de façon efficace et stable dans des microsphères de polycaprolactone. [source] Antioxidant activities of red pepper (Capsicum annuum) pericarp and seed extractsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 10 2008Ki Hyeon Sim Summary In this study, we examined the antioxidant activities of red pepper (Capsicum annuum, L.) pericarp and red pepper seed extracts. The extracts were evaluated by various antioxidant assays, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, superoxide anion radical scavenging, hydroxyl radical scavenging, [2,2,-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)] (ABTS) radical scavenging, ferrous chelating activity, superoxide dismutase (SOD) activity and reducing power, along with the determination of total phenolic and flavonoid contents. All the extracts showed strong antioxidant activity by the testing methods. The red pepper pericarp extract exhibited strong ferrous chelating activity and high scavenging activity against free radicals, including both the hydroxyl and DPPH radicals, but it exhibited weaker scavenging activity for the superoxide anion radical and for SOD. In contrast, the red pepper seed extract exhibited strong SOD activity and high scavenging activity against the superoxide anion radical, but showed weaker ferrous chelating activity, hydroxyl radical scavenging, and DPPH radical scavenging. We observed that the reducing power level and ABTS radical scavenging activity of the red pepper seed were higher than those of the red pepper pericarp at the highest tested concentration. Most of the test results for the red pepper seed and red pepper pericarp extracts increased markedly with increasing concentration; however, the metal chelating, SOD and ABTS radical scavenging activities did not increase with the concentration. Highest total phenolic and flavonoid contents were obtained from the red pepper pericarp extracts. Overall, the red pepper seed and red pepper pericarp extracts were highly effective for the antioxidant properties assayed, with the exceptions of ferrous chelating activity, hydroxyl radical scavenging and SOD activity. [source] Antioxidant polyphenols from the mycelial culture of the medicinal fungi Inonotus xeranticus and Phellinus linteusJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2008J.-Y. Jung Abstract Aims:, The medicinal fungi Inonotus xeranticus and Phellinus linteus in the family Hymenochaetaceae have been used as traditional medicines for the treatment of various diseases. However, the compound responsible for the antioxidant activity is still unknown. Therefore, this study was conducted to characterize the antioxidant substances present in cultured broths made from these fungi. Methods and Results:, Antioxidant fractions of the cultured broths obtained from I. xeranticus and P. linteus were analysed using reversed-phase HPLC, which revealed several peaks that exhibited a potent free radical scavenging activity. To identify these antioxidant peaks, an I. xeranticus strain was mass-cultured, and the cultured broth was separated using antioxidant activity-guided fractionation. Four major active substances were purified and identified as hispidin and its dimers, 3,14,-bihispidinyl, hypholomine B, and 1,1-distyrylpyrylethan based on spectroscopic analyses. All compounds exhibited a significant scavenging activity against these radical species in a concentration-dependent manner. Conclusions:, Antioxidant substances found in the cultured broths of the medicinal fungi I. xeranticus and P. linteus were identified as hispidin and its dimers, 3,14,-bihispidinyl, hypholomine B, and 1,1-distyrylpyrylethan. Significance and Impact of the Study:, Polyphenol antioxidants were isolated from the cultured broth of the medicinal fungi I. xeranticus and P. linteus and identified based on extensive spectroscopic analyses. These compounds exhibited a strong antioxidant activity. [source] Antioxidant activity of the ethanolic extract from the bark of Chamaecyparis obtusa var. formosanaJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2008Palanisamy Marimuthu Abstract BACKGROUND:Chamaecyparis obtusa var. formosana (Taiwan hinoki) is an endemic conifer in Taiwan and the purpose of this study is to evaluate the antioxidant activity of various fractions obtained from the bark of this plant material. The ethanolic extract of the bark was sequentially separated into three fractions, including n -hexane, ethyl acetate and ethanol soluble fractions, by liquid,liquid partition. Then the antioxidant activities of crude extract and three fractions along with 13 subfractions obtained from the ethyl acetate (EA) soluble fraction were tested for several antioxidant assays. RESULTS: The total phenolic content of the samples varied from 27.71 to 102.86 mg GAE g,1 dry weight for fractions, and from 49.94 to 206.46 mg GAE g,1 for subfractions (where GAE is milligrams of gallic acid per gram of extract). The Trolox equivalent antioxidant capacity (TEAC) ranged from 0.15 to 0.26 mmol L,1 Trolox equivalents. The EA soluble fraction was found to be the best antioxidant-rich fraction in terms of DPPH and reducing power assays. With further data analysis it was found that there was a positive correlation between the total phenolic content of extracts and TEAC is R2 = 0.61. CONCLUSION: Results from various antioxidant assays showed that the EA fraction possessed strong antioxidant activity. This would provide additional information about the antioxidant activity of bark extract of this plant species. Copyright © 2008 Society of Chemical Industry [source] Antioxidant activity of ginger extract in sunflower oilJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2003Zia-ur-Rehman Abstract The antioxidant activity of dichloromethane extract from ginger was evaluated during 6 months of storage of refined sunflower oil at 25 and 45,°C. Free fatty acid (FFA) content, peroxide value (POV) and iodine value (IV) were used as criteria to assess ginger extract as an antioxidant. After 6 months of storage at 45,°C, sunflower oil containing 1600 and 2400,ppm ginger extract showed lower FFA contents (0.083 and 0.080%) and POVs (24.5 and 24.0,meq,kg,1) than the control sample (FFA contents 0.380%, POV 198.0,meq,kg,1). Sunflower oil containing 200,ppm butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) showed FFA contents of 0.089 and 0.072% and POVs of 26.5 and 24.7,meq,kg,1 respectively after 6 months of storage at 45,°C. Similarly, after 6 months of storage at 45,°C, IVs of sunflower oil containing 1600 and 2400,ppm ginger extract were 80 and 92 respectively, higher than that of the control sample (53). However, IVs of sunflower oil treated with 200,ppm BHA and BHT were 94 and 96 respectively after 6 months of storage at 45,°C. These results illustrate that ginger extract at various concentrations exhibited very strong antioxidant activity, almost equal to that of synthetic antioxidants (BHA and BHT). Ginger extract also showed good thermal stability and exhibited 85.2% inhibition of peroxidation of linoleic acid when heated at 185,°C for 120,min. Therefore the use of ginger extract in foods is recommended as a natural antioxidant to suppress lipid oxidation. © 2003 Society of Chemical Industry [source] Effect of AOB, a fermented-grain food supplement, on oxidative stress in type 2 diabetic ratsBIOFACTORS, Issue 2 2007Yukiko Minamiyama Abstract Reactive oxygen species (ROS) play an important role in the pathogenesis of diabetic complications. Antioxidant Biofactor (AOB) is a mixture of commercially available fermented grain foods and has strong antioxidant activity. This study investigated the effect of AOB supplementation of standard rat food on markers of oxidative stress and inflammation in Otsuka Long-Evans Tokushima Fatty (OLETF) rats with type 2 diabetes. Blood glucose, hemoglobin A1c, plasma free fatty acid, triacylglycerol and plasminogen activator inhibitor-1 (PAI-1) were significantly higher in OLETF rats than in non-diabetic control Long-Evans Tokushima Otsuka (LETO) rats at 29 weeks. AOB (6.5% of diet) was given to rats during 29,33 weeks of diabetic phase in OLETF rats. OLETF rats with AOB supplementation showed decreased blood glucose, hemoglobin A1c, triacylgycerol, low density lipoprotein, cholesterol and PAI-1. Mitochondrial ROS production was significantly increased in heart, aorta, liver and renal artery of OLETF rats. Uncoupling protein 2 (UCP2) is known to regulate ROS production. We found aortic UCP2 protein expression increased in OLETF rats, and AOB returned UCP2 expression to normal. Aortic endothelial NO synthase (eNOS) was also increased in OLETF rats more than in LETO rats at 33 weeks. In contrast, phosphorylated vasodilator-stimulated phosphoprotein, an index of the NO-cGMP pathway, was significantly diminished. AOB increased eNOS proteins in LETO and OLETF rats. In conclusion, AOB significantly improved the NO-cGMP pathway via normalizing ROS generation in OLETF rats. The data suggest that dietary supplementation with AOB contributes to nutritional strategies for the prevention and treatment of type 2 diabetes mellitus. [source] Enantioselective synthesis and antioxidant activity of 3-(3,4-dihydroxyphenyl)-glyceric acid,Basic monomeric moiety of a biologically active polyether from Symphytum asperum and S. caucasicumCHIRALITY, Issue 8 2010Maia Merlani Abstract The racemic and enantioselective synthesis of a novel glyceric acid derivative, namely, 2,3-dihydroxy-3-(3,4-dihydroxyphenyl)-propionic acid as well as the antioxidant activities is described. The virtually pure enantiomers, (+)-(2R,3S)-2,3-dihydroxy-3-(3,4-dihydroxyphenyl)-propionic acid and (,)-(2S,3R)-2,3-dihydroxy-3-(3,4-dihydroxyphenyl)-propionic acid were synthesized for the first time via Sharpless asymmetric dihydroxylation of trans-caffeic acid derivatives using the enantiocomplementary catalysts, (DHQD)2 -PHAL and (DHQ)2 -PHAL. The determination of enantiomeric purity of the novel chiral glyceric acid derivatives was performed by high-performance liquid chromatographic techniques on the stage of their alkylated precursors. The novel glyceric acid derivatives show strong antioxidant activity against hypochlorite and N,N -diphenyl- N -picryl-hydrazyl free radical. Their antioxidant activity is about 40-fold higher than that of the corresponding natural polyether and three-fold higher of trans-caffeic acid itself. Chirality, 2010. © 2010 Wiley-Liss, Inc. [source] | |||||||||||||