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Scavenging Properties (scavenging + property)
Kinds of Scavenging Properties Selected AbstractsChemInform Abstract: New Series of Aryloxypropanolamines with Both Human ,3 -Adrenoceptor Agonistic Activity and Free Radical Scavenging Properties.CHEMINFORM, Issue 19 2002Silvere Aubriot Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] PHYCOCYANIN CONTENT OF SPIRULINA PLATENSIS DRIED IN SPOUTED BED AND THIN LAYERJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2008E.G. OLIVEIRA ABSTRACT The aim of this work was to study the drying of Spirulina platensis, evaluating the final product characteristics about its phycocyanin content and its protein solubility in water. Two drying techniques were used: the spouted bed and the thin layer. For drying in a spouted bed, the cone-cylindrical geometry was chosen, namely type conventional spouted bed (CSB) and jet-spouted bed, with a paste concentration of 5%. The thin-layer drying was performed at temperatures of 50 and 60C, with a load of material of 4 kg/m2 in the tray. The spouted bed dryer type CSB demonstrated good functionality, not presenting a collapse during the experiments. The solubility in aqueous mean was similar in all the drying techniques used, being the values found around 37%. The largest phycocyanin values were found in the thin-layer temperature of 50C and in the spouted bed type CSB; however, the thin layer was excluded so as not to reach the commercial moisture content. PRACTICAL APPLICATIONS Phycocyanin is the major phycobiliprotein in Spirulina. Phycocyanin has significant antioxidant, anti-inflammatory, hepatoprotective and radical scavenging properties. It is used as colorant in food and cosmetics. It was also shown to have therapeutic value (immunomodulating activity and anticancer activity). The drying operation is commonly used to prolong the shelf life of microbial biomasses. Preservation of cyanobacteria is a difficult process, since the cells are small and, moreover, the cultures are usually diluted. Drying of liquids and pastes in spouted beds with inert bodies has been presented as an alternative to spray drying in an attempt to obtain high-quality powdered products at a low cost. [source] In-vitro Antioxidant and In-vivo Photoprotective Effect of Three Lyophilized Extracts of Sedum telephium L. LeavesJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 10 2000FRANCESCO BONINA Sedum telephium L. is a medicinal plant used in antiquity to cure many types of inflammatory skin diseases. The leaves (without the external cuticle), are used to promote healing and reduce skin inflammation and pain, and contain various components. We found two major components: flavonol glycosides and polysaccharides, with molecular weight between 13 000 and 13 500 Da. We evaluated the in-vitro antioxidant and in-vivo skin photoprotective effects of three lyophilized extracts obtained from the juice of S. telephium L. leaves: a total lyophilized juice, a lyophilized flavonolic fraction, and a lyophilized polysaccharidic fraction. Two in-vitro models were used: the bleaching of the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH*) radical, and the protective effect against UV-induced peroxidation on phosphatidylcholine multilamellar vesicles, as model membranes. The antioxidant/radical scavenging activity of each lyophilized extract was also assessed in-vivo by determining their ability to reduce UVB-induced skin erythema (monitored by reflectance spectrophotometry) in healthy human volunteers. The findings of the in-vitro experiments clearly demonstrated that, unlike the lyophilized polysaccharidic fraction, the lyophilized flavonolic fraction and total lyophilized juice possess strong antioxidant/free radical scavenging properties, which are likely due to phenolic compounds. Consistent with these findings, gel formulations of both the total lyophilized juice and, to a greater degree, the lyophilized flavonolic fraction appeared to possess a strong protective effect against UV-induced skin erythema in-vivo, whereas the lyophilized polysaccharidic fraction was completely ineffective. The in-vitro and in-vivo results suggest that, both the total lyophilized juice and, in particular, the lyophilized flavonolic fraction, but not the lyophilized polysaccharidic fraction of S. telephium L. leaves, have photoprotective effects against UVB-induced skin damage. [source] Antioxidant and cytoprotective properties of infusions from leaves and inflorescences of Achillea collina Becker ex Rchb.PHYTOTHERAPY RESEARCH, Issue 4 2009Annamaria Giorgi Abstract Plants are the main source of molecules with antioxidant and radical scavenging properties that aid the natural defence systems of cells and may be involved in the preservation of human health, particularly preventing all the physiopathological conditions where oxidative damage is a hallmark. Achillea collina Becker ex Rchb. is a medicinal plant of the Achillea millefolium aggregate (yarrow) traditionally used, particularly in mountain areas, as an infusion or alcohol extract for its digestive, antiinflammatory, analgesic, antipyretic and wound healing properties. The aim of this study was to investigate the antioxidant capacity and cytoprotective activity against oxidative stress of infusions obtained from the leaves and inflorescences of Achillea collina Becker ex Rchb., assessed by chemical (free radical scavenging activity by DPPH and Folin Ciocalteu assay) and biological assays (in vitro model of cytotoxicity and lipid peroxidation in PC12 cells line). Infusions of leaves had the highest antioxidant properties and cytoprotective activity. The antioxidant capacity was significantly correlated with the total phenolic content but not with the cytoprotective profile. Achillea collina Becker ex Rchb. has good antioxidant and cytoprotective properties, suggesting further investigations on its chemical composition and potential health value, particularly for traditionally prepared infusions of leaves. Copyright © 2008 John Wiley & Sons, Ltd. [source] Hepatoprotective and antioxidant activities of Tetracera loureiriPHYTOTHERAPY RESEARCH, Issue 7 2003Veerapol Kukongviriyapan Abstract Tetracera loureiri is one of the most valued herbs in Thai traditional medicine. In this study, we describe its in vitro and in vivo antioxidant and hepatoprotective activities. The ethanol extract of T. loureiri possessed potent antioxidant and strong free radical scavenging properties assayed using ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH), respectively. The cytoprotective effects of T. loureiri were demonstrated in ethanolic extracts of freshly isolated rat hepatocytes against the chemical toxicants paracetamol and tertiary-butylhydroperoxide. The cells pretreated with the extract maintained the GSH/GSSG ratio and suppressed lipid peroxidation in a dose dependent manner. Pretreating rats with the ethanol extract orally, one hour prior to intraperitoneal injection of toxic doses of paracetamol, signi,cantly prevented elevations of plasma ALT and AST. These results suggest that T. loureiri may be of potential therapeutic value in some liver disorders. Copyright © 2003 John Wiley & Sons, Ltd. [source] Melatonin Counteracts Alterations in Oxidative Metabolism and Cell Viability Induced by Intracellular Calcium Overload in Human Leucocytes: Changes with AgeBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 1 2010Javier Espino In fact, the free radical theory of ageing proposes that deleterious actions of free radicals are responsible for the functional deterioration associated with ageing. Moreover, a close relationship exists between calcium homeostasis and oxidative stress. The current work was aimed at proving that intracellular calcium overload induced by N -formyl-methionyl-leucyl-phenylalanine (FMLP) and/or thapsigargin leads to oxidative stress. We additionally examined the effect of melatonin on the levels of reactive oxygen species (ROS) and cell viability in human leucocytes collected from young (20,30-year-old) and elderly (65,75-year-old) individuals under both basal and oxidative stress-induced conditions. Treatments with 10 nM FMLP and/or 1 ,M thapsigargin induced a transient increase in cytosolic free-calcium concentration ([Ca2 + ]c) in human leucocytes due to calcium release from internal stores, and led in turn to oxidative stress, as assessed by intracellular ROS measurement. Non-treated leucocytes from aged individuals exhibited higher ROS levels and lower rates of cell survival when compared to leucocytes from young individuals. Similar results were obtained in FMLP and/or thapsigargin-treated leucocytes from elderly individuals when compared to those from the young individuals. Melatonin treatment significantly reduced both hydrogen peroxide (H2O2) and superoxide anion levels, likely due to its free-radical scavenging properties, and enhanced leucocyte viability in both age groups. Therefore, melatonin may be a useful tool for the treatment of disease states and processes where an excessive production of oxidative damage occurs. [source] Protective effect of glucosamine against ibuprofen-induced peptic ulcer in ratsJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 6 2007Sethumadhavan Santhosh Abstract Background:,Helicobacter pylori is the major causative factor of ulcer but the use of ibuprofen and other non-steroidal anti-inflammatory drugs have also been implicated in development of ulcer. The purpose of the present study was to determine the anti-ulcer effect of glucosamine. Methods:, The protective effect of glucosamine on ibuprofen-induced peptic ulcer in male albino rats was studied with respect to changes in the volume of gastric juice, acid output, pepsin activity, activities of membrane bound ATPases, protein content, glycoprotein components and histopathology. Results:, Oral administration of ibuprofen caused significant increase in the number of lesions in the gastric mucosa, increases in the volume of gastric juice and acidity, and decreased activity of pepsin. The levels of protein content and glycoprotein components (hexose, hexosamine and sialic acid) and ATPase activities were also observed. Oral pretreatment with glucosamine resulted in significant reduction in the number of lesions in the gastric mucosa and decreases in the volume of gastric juice and acidity. The pepsin activity was also maintained at near normalcy. Prior oral administration of glucosamine significantly prevented the ibuprofen-induced depletion of protein and glycoprotein components and maintained the activities of membrane bound ATPases as compared to untreated ulcer induced group of rats. Conclusion:, The anti-ulcerogenic activity of glucosamine might be ascribable to its ability to neutralize the hydrochloric acid secreted into the stomach and to its capability to strengthen the mucosal barrier by increasing mucosal glycoprotein synthesis and to its free radical scavenging property. Histopathological investigations of the mucosal tissue also support the anti-ulcerogenic effect of glucosamine. [source] Screening seeds of some Scottish plants for free radical scavenging activityPHYTOTHERAPY RESEARCH, Issue 7 2007Yashodharan Kumarasamy Abstract From a consideration of ethnobotanical and taxonomic information, seeds of 45 Scottish plant species encompassing 23 different families were obtained from authentic seed suppliers. The n- hexane, dichloromethane (DCM) and methanol (MeOH) extracts were assessed, both qualitatively and quantitatively, for free radical scavenging activity in the DPPH assay. The MeOH extracts of 37 species exhibited low to high levels of free radical scavenging activity (RC50 values ranging from 2.00 to 4.7 × 10,4 mg/mL), and Alliaria petiolata, Prunus padus and Prunus spinosa were the most potent antioxidant extracts. The DCM extracts of 17 species showed similar levels of activity, and among those, Prunus padus and Prunus spinosa extracts were the most active with RC50 values of 2.5 × 10,4 and 5.0 × 10,4 mg/mL, respectively. The n -hexane extracts were much less active than the MeOH and DCM extracts, and 17 species, with the exception of Glechoma hederacea (RC50 = 1.94 × 10,4) displayed low to moderate levels of free radical scavenging property (RC50 values ranging from 2.00 to 8.7 × 10,3 mg/mL). Copyright © 2007 John Wiley & Sons, Ltd. [source] Free radical scavenging, enzyme inhibitory constituents from antidiabetic Ayurvedic medicinal plant Hydnocarpus wightiana BlumePHYTOTHERAPY RESEARCH, Issue 4 2005S. Venkat Reddy Abstract Hydnocarpus wightiana is advocated in traditional Indian medicine to possess strong antidiabetic activity. In the course of identifying bioactive fractions from Indian medicinal plants we observed that acetone extract of the seed hulls of H. wightiana possess strong free radicals (DPPH and ABTS) scavenging, , -glucosidase and moderate N-acetyl- , -D-glucosaminidase inhibitory activities. Further fractionation of the extract led to the isolation of hydnocarpin, luteolin and isohydnocarpin in substantial yields. All the compounds showed strong ABTS scavenging property. However, only luteolin could display strong DPPH scavenging activity. Furthermore, all the three compounds also showed varying degrees of , -glucosidase and N-acetyl- , -D-glucosaminidase inhibitory activity, luteolin being the superior. The kinetics of , -glucosidase inhibition by these compounds showed that acetone extract inhibits the enzyme in competitive manner however, luteolin and isohydnocarpin showed mixed-type inhibition. This is the first report assigning hydnocarpin and isohydnocarpin free radical scavenging, , -glucosidase and N-acetyl- , -D-glucosaminidase inhibitory properties and luteolin as N-acetyl- , -D-glucosaminidase inhibitor. This study suggests that presence of amphiphilic antioxidant molecules along with enzyme inhibitory activities in the acetone extract of H. wightiana seed hulls may be responsible for the antidiabetic properties as advocated in traditional medicine. Copyright © 2005 John Wiley & Sons, Ltd. [source] Hepatoprotective effect of New Liv,t®, a polyherbal formulation, is mediated through its free radical scavenging activityPHYTOTHERAPY RESEARCH, Issue 5 2004Y. K. Gupta Abstract The effect of New Liv,t®, a polyherbal formulation, was studied on pyrogallol-induced hepatotoxicity in rats. Administration of pyrogallol 100 mg/kg, i.p. caused a signi,cant increase in liver enzymes as well as a signi,cant increase in lipid peroxidation. Simultaneous administration of oral New Liv,t® and pyrogallol prevented these changes in hepatic damage. The results of the study showed that New Liv,t® exerted a hepatoprotective effect against pyrogallol induced liver toxicity, which was mediated through its free radical scavenging property. Copyright © 2004 John Wiley & Sons, Ltd. [source] Antioxidant and Hepatoprotective Effects of Cyathea phalerata Mart. (Cyatheaceae)BASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 1 2008Mariana Appel Hort The in vitro antioxidant potential of the crude extract (CE), precipitate (PPT), aqueous fraction (AQF), n-butanolic fraction (BUF) and ethyl acetate fraction (EAF) from C. phalerata was evaluated through the scavenging of diphenyl-1-picryl-hydrazyl-hydrate (DPPH), superoxide anion (O2,,) (nitroblue tetrazolium assay) and hydroxyl radicals (OH,) (deoxyribose assay), and lipid peroxidation in rat liver homogenate. In these assays, it was observed that EAF had marked antioxidant potential, especially as a scavenger of the OH, radical and in inhibiting lipid peroxidation. The in vivo evaluation of oxidative stress (DNA fragmentation, membrane lipoperoxidation and carbonyl protein formation) and the antioxidant defenses (concentration of reduced glutathione, as well as catalase and glutathione S-transferase activities) were measured in mice pre-treated with EAF (10, 30 or 100 mg/kg, orally) and later exposed to carbon tetrachloride (CCl4). The EAF decreased thiobarbituric acid reactive substances levels, DNA damage and carbonyl protein contents, and increased catalase and glutathione S-transferase activities. Based on these results, it is concluded that the EAF from C. phalerata protects liver from oxidative stress induced by CCl4 in mice and these effects are probably related to the antioxidant activity associated with the free radical scavenging property of this fraction. [source] | |||||||||||||