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Ethyl Acetate Fraction (ethyl + acetate_fraction)
Selected AbstractsThe pharmacological potential of Sorbus commixta cortex on blood alcohol concentration and hepatic lipid peroxidation in acute alcohol-treated ratsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 5 2006Syng-Ook Lee The effect of Sorbus commixta cortex, a traditional herbal medicine used for the treatment of bronchitis, gastritis and dropsy, on blood alcohol concentration (BAC) and hepatic lipid peroxidation was examined in acute alcohol-treated rats. A 30-min pretreatment with a methanol extract of S. commixta cortex (SC) at concentrations higher than 200 mg kg,1 resulted in a significant decrease in BAC and the ethyl acetate fraction (SE) of the extract showed the highest potency, with a maximum of a 46% decrease at 150 mg kg,1 2h after alcohol administration (3.0 g kg,1) compared with the control group (P < 0.005). The rapid reduction in BAC did not appear to be due to the protection or activation of hepatic alcohol dehydrogenase (ADH) activity by SE. Hepatic malondialdehyde (MDA) levels were significantly increased by acute alcohol administration within 6h, although pretreatment with the SE caused a significant decrease in MDA levels compared with alcohol treatment alone. Hepatic glutathione (GSH) levels and superoxide dismutase (SOD) activity remained unchanged by alcohol, SE alone or by the combined treatment of alcohol and SE. However, catalase activity was significantly reduced by acute alcohol administration and pretreatment with the SE led to significant protection of its activity. These results suggest that pretreatment with SE reduces hepatic lipid peroxidation by decreasing the bioavailability of alcohol and its oxidative metabolites, such as H2O2, at least partly, through the protection of hepatic catalase in acute alcohol-treated rats. [source] Radical scavenging and anti-inflammatory activity of extracts from Opuntia humifusa Raf.JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 1 2006J. Y. Cho Opuntia humifusa Raf. (O. humifusa Raf.) is a member of the Cactaceae family. To determine the antioxidative and anti-inflammatory effects of this herb, various solvent fractions (methanol, hexane, chloroform, ethyl acetate, butanol, and water) prepared from the leaves of cacti were tested using DPPH (2,2-diphenyl-l-picrylhydrazyl radical) and xanthine oxidase assays, and nitric oxide (NO)-producing macrophage cells. We found that O. humifusa Raf. displayed potent antioxidative and anti-inflammatory activity. Thus, all solvent fractions, except for the water layer, showed potent scavenging effects. The scavenging effect of the ethyl acetate fraction was higher than that of the other fractions, with IC50 values of 3.6 and 48.2 ,g mL,1. According to activity-guided fractionation, one of the active radical scavenging principles in the ethyl acetate fraction was found to be quercetin. In contrast, only two fractions (chloroform and ethyl acetate) significantly suppressed nitric oxide production from the lipopolysaccharide (LPS)-activated RAW264.7 cells. In addition, chloroform and ethyl acetate fractions significantly blocked the expression of inducible nitric oxide synthetase (iNOS) and interleukin-6 (IL-6) from the RAW264.7 cells stimulated by LPS. Moreover, ethyl acetate fractions significantly blocked the expression of IL-1, from the RAW264.7 cells stimulated by LPS. Therefore, the results suggested that O. humifusa Raf. may modulate radical-induced toxicity via both direct scavenging activity and the inhibition of reactive species generation, and the modulation of the expression of inflammatory cytokines. Finally, O. humifusa Raf. may be useful as a functional food or drug against reactive species-mediated disease. [source] Structural determination of kochiosides A,C, new steroidal glucosides from Kochia prostrata, by 1D and 2D NMR spectroscopyMAGNETIC RESONANCE IN CHEMISTRY, Issue 9 2007Muhammad Imran Abstract Kochiosides A,C, three new steroidal glucosides, have been isolated from the ethyl acetate fraction of Kochia prostrata and their structures assigned from its 1H and 13C NMR spectra, DEPT and by 2D COSY, NOESY, HMQC and HMBC experiments. Copyright © 2007 John Wiley & Sons, Ltd. [source] Structural determination of silymins A and B, new pentacyclic triterpenes from Silybum marianum, by 1D and 2D NMR spectroscopyMAGNETIC RESONANCE IN CHEMISTRY, Issue 1 2007Ejaz Ahmed Abstract Silymins A (1) and B (2), the new pentacyclic triterpenes, have been isolated from ethyl acetate fraction of Silybum marianum and their structures assigned from 1H and 13C NMR spectra, DEPT and by 2D COSY, NOE and HMBC experiments. Copyright © 2007 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] Essential oil composition and antimicrobial activity of tuberous roots of Pimpinella tirupatiensis Bal.FLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2002& Subr., India, an endemic taxon from eastern ghats Abstract The tuberous roots of Pimpinella tirupatiensis (Apiaceae) were subjected to sequential extraction with different polar solvents and the extracts were tested against eight bacterial and three fungal pathogenic strains for antimicrobial activity. The minimum inhibitory concentration of active extracts against six bacterial and two fungal strains were determined. The hexane and ethyl acetate fractions exhibited a broad spectrum of antimicrobial activity and were analysed for different phytochemicals. The active extracts contained significant amounts of alkaloids, flavonols, flavones and volatile oils. The hexane extract yielded an essential oil when subjected to GC with FID. The compounds were identified based on their retention indices and yielded 24 known compounds and one unknown compound. The major compounds are ,-bisabolene (9.2%), ,-3-carene (8.9%), cis -carveol (6.7%), elemol (5.8%), ,-cadinol (4.4%), methyl geranate (4.3%) and ,-nonalactone (3.4%). Copyright © 2002 John Wiley & Sons, Ltd. [source] Radical scavenging and anti-inflammatory activity of extracts from Opuntia humifusa Raf.JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 1 2006J. Y. Cho Opuntia humifusa Raf. (O. humifusa Raf.) is a member of the Cactaceae family. To determine the antioxidative and anti-inflammatory effects of this herb, various solvent fractions (methanol, hexane, chloroform, ethyl acetate, butanol, and water) prepared from the leaves of cacti were tested using DPPH (2,2-diphenyl-l-picrylhydrazyl radical) and xanthine oxidase assays, and nitric oxide (NO)-producing macrophage cells. We found that O. humifusa Raf. displayed potent antioxidative and anti-inflammatory activity. Thus, all solvent fractions, except for the water layer, showed potent scavenging effects. The scavenging effect of the ethyl acetate fraction was higher than that of the other fractions, with IC50 values of 3.6 and 48.2 ,g mL,1. According to activity-guided fractionation, one of the active radical scavenging principles in the ethyl acetate fraction was found to be quercetin. In contrast, only two fractions (chloroform and ethyl acetate) significantly suppressed nitric oxide production from the lipopolysaccharide (LPS)-activated RAW264.7 cells. In addition, chloroform and ethyl acetate fractions significantly blocked the expression of inducible nitric oxide synthetase (iNOS) and interleukin-6 (IL-6) from the RAW264.7 cells stimulated by LPS. Moreover, ethyl acetate fractions significantly blocked the expression of IL-1, from the RAW264.7 cells stimulated by LPS. Therefore, the results suggested that O. humifusa Raf. may modulate radical-induced toxicity via both direct scavenging activity and the inhibition of reactive species generation, and the modulation of the expression of inflammatory cytokines. Finally, O. humifusa Raf. may be useful as a functional food or drug against reactive species-mediated disease. [source] In vitro and in vivo effects of Ranunculus peltatus subsp. baudotii methanol extract on models of eicosanoid production and contact dermatitisPHYTOTHERAPY RESEARCH, Issue 3 2008J. M. Prieto Abstract Ranunculus (Crowfoot) species are numerous and they are all reputed to be counter-irritants and are used in several topical conditions. In order to study the pharmacological mechanisms of action underlying this popular use, a methanol extract of Ranunculus peltatus was tested in vitro in various assays involving eicosanoid and human elastase release by intact cells as well as in vivo, with models of delayed-type hypersensitivity (DTH) contact dermatitis. The extract proved to be a selective inhibitor of the cyclooxygenase-1 pathway, producing the total inhibition of 12-(S)-HHTrE release at 200 µg/mL, while leaving both 5-lipoxygenase and 12-lipoxygenase activities unaffected at the same dose. The n -hexane, chloroform and ethyl acetate fractions of the crude methanol extract inhibited LTB4 release by intact rat peritoneal neutrophils, but more polar fractions were inactive and did not increase the 5-LOX activity as seen previously for extracts of other Ranunculus species. In the in vivo models, the methanol extract reduced the dinitrofluorobenzene (DNFB)-induced oedema by 40%, but failed to inhibit the oedema brought on by oxazolone. The results agree with the age-old assertion that Water Crowfoot species can be used as a topical antiinflammatory remedy without the prominent irritant action that accompanies the application of non-aquatic Ranunculus species. Copyright © 2007 John Wiley & Sons, Ltd. [source] Lignans from Acanthopanax chiisanensis having an inhibitory activity on prostaglandin E2 productionPHYTOTHERAPY RESEARCH, Issue 2 2005Sanghyun Lee Abstract The chloroform and the ethyl acetate fractions from the roots of Acanthopanax chiisanensis exhibited the significant inhibition of TPA-induced prostaglandin E2 (PGE2) production in rat peritoneal macrophages. Five lignans were isolated from the chloroform fraction and their structures were elucidated as l -sesamin, helioxanthin, savinin, taiwanin C, and 3-(3,4-dimethoxybenzyl)-2-(3,4-methylenedioxybenzyl)butyrolactone. Among the lignans tested, taiwanin C showed the most potent inhibitory activity (IC50 = 0.12 µM) on PGE2 production with the relative order of potency, taiwanin C , 3-(3,4-dimethoxybenzyl)-2-(3,4-methylenedioxybenzyl)butyrolactone > savinin = helioxanthin. l -Sesamin showed no inhibitory activity at 30 µM. Copyright © 2005 John Wiley & Sons, Ltd. [source] | |||||||||||||