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Compound Isolated (compound + isolated)
Selected AbstractsEffects of Compounds Isolated from the Fruits of Rumex japonicus on the Protein GlycationCHEMISTRY & BIODIVERSITY, Issue 12 2008Sik Jang Abstract An anthraquinone, emodin (1), and five flavonoids, kaempferol-3- O - ,- D -glucoside (2), quercetin (3), quercitrin (4), isoquercitrin (5), and (+)-catechin (6), were isolated from an AcOEt-soluble extract of the fruits of Rumex japonicus. Their structures were determined by spectroscopic data interpretation. All the isolates were evaluated for their potential to inhibit AGEs (advanced glycation end products) formation and AGEs cross-linking, and to break already formed AGEs cross-links. [source] Catalposide, a compound isolated from Catalpa Ovata, attenuates induction of intestinal epithelial proinflammatory gene expression and reduces the severity of trinitrobenzene sulfonic acid-induced colitis in miceINFLAMMATORY BOWEL DISEASES, Issue 5 2004Sang-Wook Kim MD Abstract Certain irinoid-producing plants have been used as herbal anti-inflammatory remedies. Here we evaluated whether catalposide (CATP), a single compound isolated from irinoid-producing plant Catalpa ovata, has a potential for preventing or ameliorating diseases characterized by mucosal inflammation. Preliminary microarray-based gene expression test revealed that CATP, which alone did not significantly affect expression of any of the >8,000 genes analyzed, attenuated the expression of tumor necrosis factor-, (TNF-,)-induced proinflammatory genes including interleukin-8 (IL-8) in human intestinal epithelial HT-29 cells. Down-regulation of IL-8 mRNA accumulation was also reflected by the decreased IL-8 secretion in CATP-treated HT-29 cells. The signal transduction study revealed that CATP significantly attenuates TNF-,-mediated p38 and extracellular signal-regulated kinase (ERK) phosphorylation. Further, CATP reduced NF-,B-mediated transcriptional activation as well as I,-B, degradation. To establish the in vivo relevance of these findings, we examined whether CATP could affect intestinal inflammation in vivo using the mouse model of trinitrobenzene sulfonic acid (TNBS)-induced inflammatory colitis. Intrarectal administration of CATP dramatically reduced the weight loss, colonic damage, and mucosal ulceration that characterize TNBS colitis. Moreover, CATP suppressed the expression of TNF-,, interleukin-1,, and intercellular adhesion molecule-1 along with the inhibition of NF-, B p65 translocation into nucleus in TNBS colitis. Collectively, current results demonstrate that CATP may be an effective agent for the treatment of diseases characterized by mucosal inflammation. [source] Purification and characterization of a bacteriocin-like compound (Lichenin) produced anaerobically by Bacillus licheniformis isolated from water buffaloJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2001P. Pattnaik Aims:,To characterize a bacteriocin-like factor from Bacillus licheniformis 26 L-10/3RA isolated from buffalo rumen. Methods and Results:,The culture supernatant exhibited the antibacterial activity against a number of indicator organisms in a cut-well agar assay under anaerobic conditions. The inhibitory component was purified by following ammonium sulphate precipitation, gel filtration and ion exchange chromatography and confirmed to be a single peptide. A single band on tricine-sodium dodecyl sulphate-polyacrylamide gel electrophoresis confirmed that the peptide was purified to homogeneity and having an estimated molecular mass of approximately 1400 dalton. Complete amino acid sequence of the peptide yielded 12 amino acids from the N-terminal end (ISLEICXIFHDN). No homology with previously reported bacteriocins was observed and has been designated as Lichenin. Lichenin was found to be hydrophobic, sensitive to atmospheric oxygen, retained biological activity even after boiling for 10 min and was active over a pH range of 4·0,9·0. Conclusions:,The Lichenin represents the first anaerobiosis specific expression of bacteriocin-like compound isolated from Bacillus licheniformis 26 L-10/3RA of buffalo rumen origin. Significance and Impact of the Study:,Lichenin could be a potential condidate for manipulating the rumen function at molecular level intended for improving the productivity of the ruminant. [source] Antihyperlipidemic activity of 3-hydroxymethyl xylitol, a novel antidiabetic compound isolated from Casearia esculenta (Roxb.) root, in streptozotocin-diabetic ratsJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 2 2010Govindasamy Chandramohan Abstract Casearia esculenta root (Roxb.) is widely used in traditional system of medicine to treat diabetes in India. An active compound, 3-hydroxymethyl xylitol (3-HMX), has been isolated, and its optimum dose has been determined in a short duration study and patented. In addition, the long-term effect of 3-HMX in type 2 diabetic rats on carbohydrate metabolism was investigated, and its antihyperglycemic effect was shown previously (Chandramohan et al., Eur J Pharmacol 2008;590:437,443). In this study we investigated the effect of 3-HMX on plasma and tissue lipid profiles in streptozotocin-induced diabetic rats. Diabetes was induced in adult male albino rats of the Wistar strain, weighing 180,200 g, by administration of streptozotocin (40 mg/kg of body weight) intraperitoneally. The normal and diabetic rats were treated with 3-HMX (40 mg/kg BW/day) for 45 days. The levels of total cholesterol, triglycerides, free fatty acids, and phospholipids were assayed in the plasma besides lipoprotein-cholesterol (high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), and very low density lipoprotein-cholesterol (VLDL-C)) and tissues (liver, kidney, heart, and brain). Total cholesterol, triglyceride, free fatty acid, and phospholipid (LDL-C and VLDL-C in plasma only) levels increased in plasma and tissues significantly, whereas plasma HDL-C significantly decreased in diabetic rats. Treatment with 3-HMX or glibenclamide reversed the above-mentioned changes and improved toward normalcy. Histological study of liver also confirmed the biochemical findings. Thus administration of 3-HMX is able to reduce hyperglycemia and hyperlipidemia related to the risk of diabetes mellitus. © 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 24:95,101, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20317 [source] Eutigoside C inhibits the production of inflammatory mediators (NO, PGE2, IL-6) by down-regulating NF-,B and MAP kinase activity in LPS-stimulated RAW 264.7 cellsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 7 2008Hye-Ja Lee Eutigoside C, a compound isolated from the leaves of Eurya emarginata, is thought to be an active anti-inflammatory compound which operates through an unknown mechanism. In the present study we investigated the molecular mechanisms of eutigoside C activity in lipopolysacchardide (LPS)-stimulated murine macrophage RAW 264.7 cells. Treatment with eutigoside C inhibited LPS-stimulated production of nitric oxide (NO), prostaglandin E2 (PGE2) and interleukin-6 (IL-6). To further elucidate the mechanism of this inhibitory effect of eutigoside C, we studied LPS-induced nuclear factor (NF)-,B activation and mitogen-activated protein (MAP) kinase phosphorylation. Eutigoside C suppressed NF-,B DNA binding activity, interfering with nuclear translocation of NF-,B. Eutigoside C suppressed the phosphorylation of three MAP kinases (ERK1/2, JNK and p38). These results suggest that eutigoside C inhibits the production of inflammatory mediators (NO, PGE2 and interleukin-6) by suppressing the activation and translocation of NF-,B and the phosphorylation of MAP kinases (ERK1/2, JNK and p38) in LPS-stimulated murine macrophage RAW 264.7 cells. [source] Antiplatelet Effect of Marchantinquinone, Isolated from Reboulia hemisphaerica, in Rabbit Washed PlateletsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 3 2000CHANG-HUI LIAO Platelet activation is involved in serious pathological situations, including atherosclerosis and restenosis. It is important to find efficient antiplatelet medicines to prevent fatal thrombous formation during the course of these diseases. Marchantinquinone, a natural compound isolated from Reboulia hemisphaerica, inhibited platelet aggregation and ATP release stimulated by thrombin (0.1 units mL,1), platelet-activating factor (PAF; 2 ng mL,1), collagen (10 ,g mL,1), arachidonic acid (100 ,m), or U46619 (1 ,m) in rabbit washed platelets. The IC50 values of marchantinquinone on the inhibition of platelet aggregation induced by these five agonists were 62.0 ± 9.0, 86.0 ± 7.8, 13.6 ± 4.7, 20.9 ± 3.1 and 13.4 ± 5.3 ,m, respectively. Marchantinquinone inhibited thromboxane B2 (TxB2) formation induced by thrombin, PAF or collagen. However, marchantinquinone did not inhibit TxB2 formation induced by arachidonic acid, indicating that marchantinquinone did not affect the activity of cyclooxygenase and thromboxane synthase. Marchantinquinone did inhibit the rising intracellular Ca2+ concentration stimulated by the five platelet-aggregation inducers. The formation of inositol monophosphate induced by thrombin was inhibited by marchantinquinone. Platelet cAMP and cGMP levels were unchanged by marchantinquinone. The results indicate that marchantinquinone exerts antiplatelet effects by inhibiting phosphoinositide turnover. [source] Apoptosis of BGC823 cell line induced by p -hydroxymethoxybenzobijuglone, a novel compound from Juglans mandshuricaPHYTOTHERAPY RESEARCH, Issue 4 2009ZhiBo Li Abstract p -Hydroxymethoxybenzobijuglone (HMBBJ), a new quinone compound isolated from Juglans mandshurica (by bioassay-guided fractionation), showed cytotoxic activity in the gastric carcinoma cell line BGC823. The growth of BGC823 cells was inhibited as demonstrated by MTT assay and several cellular characteristic changes, such as cell shrinkage, chromatin condensation and apoptotic body formation with programmed cell death. Flow cytometry analysis revealed that the BGC823 cell cycle was arrested at G2/M phase by HMBBJ, and the apoptotic rate of BGC823 cells increased with respect to HMBBJ in a dose-dependent manner. HMBBJ also activated caspase-3, decreased the expression of Bcl-2 and caused a decrease in the mitochondrial membrane potential (,,m). These findings suggest that HMBBJ could significantly induce apoptosis in BGC823 cells and should be considered as a potential candidate for a chemotherapeutic drug against cancer. Copyright © 2008 John Wiley & Sons, Ltd. [source] Isolation, structure elucidation and In Vivo hepatoprotective potential of trans -tetracos-15-enoic acid from Indigofera tinctoria Linn.PHYTOTHERAPY RESEARCH, Issue 10 2006B. Singh Abstract The bioassay guided fractionation of the dried aerial part of Indigofera tinctoria Linn. led to the identification of an active fraction labelled as indigotin. On further chemical analysis, a compound isolated from indigotin was identified and characterized as trans- tetracos -15-enoic acid (TCA). The chemical structure of this compound was established on the basis of physical properties and spectral data, including NMR. It afforded significant hepatoprotection against carbon tetrachloride and paracetamol induced hepatotoxicity in experimental models. Silymarin, a well known plant based hepatoprotective agent, and N -acetylcysteine, which has proven efficacy as a replenisher of sulfhydryls, were used for relative efficacy. TCA was found to reverse the altered hepatic parameters in experimental liver damage. In the safety evaluation study the oral LD50 was found to be more than 2000 mg/kg, with no signs of abnormalities or any mortality for the 15 day period of observation after administration of a single dose of drug in mice. The studies revealed significant and concentration dependent hepatoprotective potential of TCA as it reversed the majority of the altered hepatic parameters in experimental liver damage in rats and mice and may be useful in the management of liver disorders. Copyright © 2006 John Wiley & Sons, Ltd. [source] Inhibitory effect of magnolol on tumour metastasis in micePHYTOTHERAPY RESEARCH, Issue 8 2003Koji Ikeda Abstract It has previously been reported that magnolol, a phenolic compound isolated from Magnolia obovata, inhibited tumour cell invasion in vitro. The purpose of this study was to investigate the antimetastatic effect of magnolol on tumour metastasis in vivo with experimental and spontaneous metastasis models and to clarify the mechanism. The antimetastatic effects of magnolol were evaluated by an experimental liver and spleen metastasis model using L5178Y-ML25 lymphoma, or an experimental and spontaneous lung metastasis model using B16-BL6 melanoma. Intraperitoneal (i.p.) administration of 2 or 10 mg/kg of magnolol signi,cantly suppressed liver and spleen metastasis or lung metastasis. As for the spontaneous lung metastasis model using B16-BL6 melanoma, multiple i.p. administrations of 10 mg/kg of magnolol after and before tumour inoculation signi,cantly suppressed lung metastasis and primary tumour growth. In addition, magnolol signi,cantly inhibited B16-BL6 cell invasion of the reconstituted basement membrane (Matrigel, MG) without affecting cell growth. These data from the in vivo experiments suggest that magnolol possesses strong antimetastatic ability and that it may be a lead compound for drug development. The antimetastatic action of magnolol is considered to be due to its ability to inhibit tumour cell invasion. Copyright © 2003 John Wiley & Sons, Ltd. [source] Identification of a potent antibacterial factor isolated from bronchoalveolar lavage fluid: guanidine, N -[3-[(aminoiminomethyl)amino]propyl]- N -dodecyl-, a potential source of error in the analysis of antibacterial agentsRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 3 2003Mirna Abraham-Nordling The widespread use of antibiotics in modern society has encouraged the search for new antibacterial compounds. In this laboratory investigations are being made to identify and characterise novel antibacterial peptides. With this in mind, the antibacterial properties of human bronchoalveolar lavage (BAL) fluid from sarcoidosis patients is being investigated. In this communication we report on the identification and characterisation of a highly active non-peptide antibacterial compound isolated from BAL fluid. The structure of this active compound was elucidated by high-resolution accurate mass and tandem mass spectrometry to be guanidine, N -[3-[(aminoiminomethyl)amino]propyl]- N -dodecyl-. This compound does not appear to be endogenous, and its presence in BAL fluid extracts presents a potential source of error in analysis of antibacterial agents. The biological effects of guanidine, N -[3-[(aminoiminomethyl)amino]propyl]- N -dodecyl- have not previously been described in the literature. Copyright © 2002 John Wiley & Sons, Ltd. [source] Cell death induction by isothiocyanates and their underlying molecular mechanismsBIOFACTORS, Issue 2 2006Yoshimasa Nakamura Abstract An important and promising group of compounds that have a chemopreventive property are organosulfur compounds, such as isothiocyanates (ITCs). In recent years, it has been shown that ITCs induce apoptosis in various cancer cell lines and experimental rodents. During the course of apoptosis induction by ITC, multiple signal-transduction pathways and apoptosis intermediates are modulated. We have also clarified the molecular mechanism underlying the relationship between cell cycle arrest and apoptosis induced by benzyl isothiocyanate (BITC), a major ITC compound isolated from papaya. The exposure of cells to BITC resulted in the inhibition of the G2/M progression that coincided with not only the up-regulated expression of the G2/M cell cycle arrest-regulating genes but also the apoptosis induction. The experiment using the phase-specific synchronized cells demonstrated that the G2/M phase-arrested cells are more sensitive to undergoing apoptotic stimulation by BITC than the cells in other phases. We identified the phosphorylated Bcl-2 as a key molecule linking the p38 MAPK-dependent cell cycle arrest with the JNK activation by BITC. We also found that BITC induced the cytotoxic effect more preferentially in the proliferating normal human colon epithelial cells than in the quiescent cells. Conversely, treatment with an excessive concentration of BITC resulted in necrotic cell death without DNA ladder formation. This review addresses the biological impact of cell death induction by BITC as well as other ITCs and the involved signal transduction pathways. [source] Antimicrotubular and cytotoxic activity of geiparvarin analogues, alone and in combination with paclitaxelCELL BIOCHEMISTRY AND FUNCTION, Issue 3 2001Antonella Miglietta Abstract Geiparvarin is an antiproliferative compound isolated from the leaves of Geijera parviflora, and may represent a new drug which targets tubulin. To better explore the potential use of this agent, we investigated the antimicrotubular and cytotoxic effects of new synthetic aromatic derivatives of geiparvarin. These drugs inhibited polymerization of microtubular protein, particularly when the assembly was induced by paclitaxel. The microtubular network organization of fibroblasts was altered more effectively by some drugs. Normal microtubule architecture completely disappeared when the cells were treated simultaneously with drugs and paclitaxel: microtubules depolymerized or were reorganized into bundles, in a similar but more disarrayed fashion than that observed after treatment with paclitaxel alone. Cytotoxicity studies showed a dose-dependent effect, whereas combined administration of drugs and paclitaxel increased cytotoxicity, more effectively in paclitaxel versus derivatives administration alone. Copyright © 2001 John Wiley & Sons, Ltd. [source] Insulin Secretagogues from Moringa oleifera with Cyclooxygenase Enzyme and Lipid Peroxidation Inhibitory ActivitiesHELVETICA CHIMICA ACTA, Issue 2 2004Jayaraj Bioassay-directed isolation and purification of the methanol extract of Moringa oleifera fruits yielded bioactive N -benzyl thiocarbamates, N -benzyl carbamates, benzyl nitriles, and a benzyl ester. Among these, methyl 2-[4-(, - L -rhamnopyranosyl)phenyl]acetate (2), N -[4-(, - L -rhamnopyranosyl)benzyl]-1- O - , - D -glucopyranosylthiocarboxamide (3), 1- O -phenyl- , - L -rhamnopyranoside (5), and 4-[(, - D -glucopyranosyl)-(1,3)-(, - L -rhamnopyranosyl)]phenylacetonitrile (6) are novel, and their structures were determined by spectroscopic methods. The known compounds isolated and characterized from the MeOH extract were niazirin (=4-(, - L -rhamnopyranosyl)phenylacetonitrile; 1), niazicin A (=methyl N -{4-[(4,- O -acetyl- , - L -rhamnopyranosyl)benzyl]}thiocarbamate; 4), methyl N -{4-[(, - L -rhamnopyranosyl)benzyl]}carbamate (7), and methyl N -{4-[(4,- O -acetyl- , - L -rhamnopyranosyl)benzyl]}carbamate (8). The combined yield of these compounds from dried M. oleifera fruits was 1.63%. In rodent pancreatic , -cells (INS-1), compounds 4, 5, 6, 7, and 8 at 100,ppm significantly stimulated insulin release. Cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) enzyme inhibition assays revealed that 5 and 6 were most active at 83,ppm. Compound 6, however, demonstrated greater specificity for inhibition of COX-2 enzyme (46%) than COX-1 enzyme. Lipid peroxidation assays revealed that 4 and 6 at 50,ppm inhibited peroxidation reactions by 80 and 95%, respectively, while 3 and 8 inhibited lipid peroxidation by 35%. These compounds did not inhibit the cell growth when tested with human breast (MCF-7), central nervous system (CNS, SF-268), lung (NCI-H460), or colon (HCT-116) cancer cell lines. Moreover, these compounds were not cytotoxic at the concentrations tested. [source] Identifying the differential effects of silymarin constituents on cell growth and cell cycle regulatory molecules in human prostate cancer cellsINTERNATIONAL JOURNAL OF CANCER, Issue 1 2008Gagan Deep Abstract Prostate cancer (PCa) is the leading cause of cancer-related deaths in men; urgent measures are warranted to lower this deadly malignancy. Silymarin is a known cancer chemopreventive agent, but the relative anticancer efficacy of its constituents is still unknown. Here, we compared the efficacy of 7 pure flavonolignan compounds isolated from silymarin, namely silybin A, silybin B, isosilybin A, isosilybin B, silydianin, isosilydianin, silychristin and isosilychristin, in advanced human PCa PC3 cells. Silybin A, silybin B, isosilybin A, isosilybin B, silibinin and silymarin strongly inhibited the colony formation by PC3 cells (p < 0.001), while silydianin, silychristin and isosilychristin had marginal effect (p < 0.05). Using cell growth and death assays, we identified isosilybin B as the most effective isomer. FACS analysis for cell cycle also showed that silybin A, silybin B, isosilybin A, isosilybin B, silibinin and silymarin treatment resulted in strong cell cycle arrest in PC3 cells after 72 hr of treatment, while the effect of silydianin, silychristin and isosilychristin was marginal (if any). Western blot analysis also showed the differential effect of these compounds on the levels of cell cycle regulators-cyclins (D, E, A and B), CDKs (Cdk2, 4 and Cdc2), CDKIs (p21 and p27) and other cell cycle regulators (Skp2, Cdc25A, B, C and Chk2). This study provided further evidence for differential anticancer potential among each silymarin constituent, which would have potential implications in devising better formulations of silymarin against prostate and other cancers. © 2008 Wiley-Liss, Inc. [source] Antimalarial compounds isolated from plants used in traditional medicineJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2009Joanne Bero Abstract Objectives This review covers the compounds with antiplasmodial activity isolated from plants published from 2005 to the end of 2008, organized according to their phytochemical classes. Details are given for substances with IC50 values , 11 ,M. Key findings Malaria is a major parasitic disease in many tropical and subtropical regions and is responsible for more than 1 million deaths each year in Africa. The rapid spread of resistance encourages the search for new active compounds. Nature and particularly plants used in traditional medicine are a potential source of new antimalarial drugs as they contain molecules with a great variety of structures and pharmacological activities. Summary A large number of antimalarial compounds with a wide variety of structures have been isolated from plants and can play a role in the development of new antimalarial drugs. Ethnopharmacological approaches appear to be a promising way to find plant metabolites that could be used as templates for designing new derivatives with improved properties. [source] The sacred lotus (Nelumbo nucifera), phytochemical and therapeutic profileJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2009Dr Pulok K. Mukherjee Abstract ObjectivesNelumbo nucifera Gaertn. (Nymphaeaceae), also known as sacred lotus, is a well known medicinal plant. This article reviews the traditional uses, phytochemistry and therapeutic reports on different parts of N. nucifera viz. the seeds, rhizomes, leaves and flowers. This review also describes various compounds isolated from different parts of this plant and the therapeutic benefits derived from those phytoconstituents. Key findings There are several therapeutic benefits of this plant for which different parts are used. The extracts of rhizomes, seeds, flowers and leaves have been reported to have varied therapeutic potential. Several bioactive compounds have been derived from these plant parts belonging to different chemical groups, including alkaloids, flavonoids, glycosides, triterpenoid, vitamins etc., which all have their own therapeutic impact. Thus, the pharmacological effects and various active ingredients of different parts of N. nucifera are well understood. Summary In this review we explore the current pharmaceutical, phytochemical and pharmacological knowledge about this well known plant species as well as several emerging aspects for research on N. nucifera. [source] In vitro studies on antioxidant activity of lignans isolated from sesame cake extractJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2005Kizhiyedathu Polachira Suja Abstract The antioxidant activity of compounds isolated from a methanolic extract of commercial sesame cake was studied using a peroxidation model and a radical-scavenging method. Pure compounds were isolated from the extract by preparative high-performance liquid chromatography (HPLC) and identified and confirmed as sesamol, sesamin, sesamolin, sesaminol diglucoside and sesaminol triglucoside by HPLC, infrared, nuclear magnetic resonance and mass spectrometry. When the rate of inhibition of lipid peroxidation and the superoxide radical-scavenging power of the individual compounds were evaluated, the compounds showed antioxidant activity to different extents. The antioxidant activity of compounds by the ,-carotene-bleaching assay followed the order sesamol > sesamolin , sesamin > butylated hydroxytoluene (BHT) > sesaminol triglucoside > sesaminol diglucoside. By the thiocyanate method the inhibition of linoleic acid peroxidation shown by sesamol, sesamin, sesamolin, sesaminol triglucoside, sesaminol diglucoside and BHT at 200 mg l,1 was 77, 60, 69, 32, 25 and 49% respectively. A concentration,dependent superoxide,scavenging effect was also shown by these compounds. Sesamolin had an appreciable effect at 300 and 500 mg l,1, while the other compounds were more effective at 100 mg l,1. The study also established the occurrence of sesamol in the methanolic extract of defatted sesame cake for the first time. Copyright © 2005 Society of Chemical Industry [source] Antimicrobial activities of eucalyptus leaf extracts and flavonoids from Eucalyptus maculataLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2004T. Takahashi Abstract Aims:, We investigated the antimicrobial activities of eucalyptus leaf extracts to find effective antibacterial agents. Methods and Results:, The antimicrobial activities of leaf extracts from 26 species of eucalyptus were measured. Extracts of Eucalyptus globulus, E. maculata and E. viminalis significantly inhibited the growth of six Gram-positive bacteria (Staphylococcus aureus, MRSA, Bacillus cereus, Enterococcus faecalis, Alicyclobacillus acidoterrestris, Propionibacterium acnes), and of a fungus (Trichophyton mentagrophytes), but they did not show strong antibacterial activity against Gram-negative bacteria (Escherichia coli, Pseudomonas putida). 2,,6,-dihydroxy-3,-methyl-4,-methoxy-dihydrochalcone, eucalyptin and 8-desmethyl-eucalyptin, isolated from E. maculata extracts, exhibited potent antimicrobial activities against seven micro-organisms with minimum inhibitory concentrations (MIC) ranging from 1·0 to 31 mg l,1. Conclusions:, The eucalyptus extracts and three compounds from E. maculata were found to be effective against micro-organisms that cause food poisoning, acne and athlete's foot. Significance and Impact of the Study:, This study shows potential uses of extracts from E. globulus, E. maculata and E. viminalis, and antimicrobial compounds isolated from E. maculata. [source] Comparison of the antiobesity effects of the protopanaxadiol- and protopanaxatriol-type saponins of red ginsengPHYTOTHERAPY RESEARCH, Issue 1 2009Ji Hyun Kim Abstract A previous study demonstrated that ginseng crude saponins prevent obesity induced by a high-fat diet in rats. Ginseng crude saponins are known to contain a variety of bioactive saponins. The present study investigated and compared the antiobesity activity of protopanaxadiol (PD) and protopanaxatriol (PT) type saponins, major active compounds isolated from crude saponins. Male 4-week-old Sprague-Dawley rats were fed with normal diet (N) or high-fat diet (HF). After 5 weeks, the HF diet group was subdivided into the control HF diet, HF diet-PD and HF diet-PT group (50 mg/kg/day, 3 weeks, i.p.). Treatment with PD and PT in the HF diet group reduced the body weight, total food intake, fat contents, serum total cholesterol and leptin to levels equal to or below the N diet group. The hypothalamic expression of orexigenic neuropeptide Y was significantly decreased with PD or PT treatment, whereas that of anorexigenic cholecystokinin was increased, compared with the control HF diet group. In addition, PD type saponins had more potent antiobesity properties than PT saponins, indicating that PD-type saponins are the major components contributing to the antiobesity activities of ginseng crude saponins. The results suggest that the antiobesity activity of PD and PT type saponins may result from inhibiting energy gain, normalizing hypothalamic neuropeptides and serum biochemicals related to the control of obesity. Copyright © 2008 John Wiley & Sons, Ltd. [source] Effects of phenolic compounds isolated from Rabdosia japonica on B16-F10 melanoma cellsPHYTOTHERAPY RESEARCH, Issue 7 2008Teruhiko Nitoda Abstract Pedalitin isolated from the aerial part of Rabdosia japonica (Labiatae), exhibited cytotoxicity against the murine B16-F10 melanoma cell line with an IC50 of 30 µm (9.5 µg/mL). As the cells were cultured with this flavone, melanin production was not suppressed, but rather enhanced. Quercetin isolated from the same source exhibited similar activities, but rutin showed neither activity. Copyright © 2008 John Wiley & Sons, Ltd. [source] Chemistry and antioxidative factors in rosemary and sageBIOFACTORS, Issue 1-4 2000Chi-Tang Ho Rosemary and sage are common spices used in food. In our recent search of cancer chemopreventive agents from spices, the alcohol extracts of rosemary and sage showed strong antumorigenic activities. Rosemary and sage extracts contain active antioxidative factors such as phenolic diterpenes, flavonoids and phenolic acids. Here we discuss chromatographic methods used to separate and purify compounds from these spices and MS and NMR spectrometry to identify the isolated compounds. Several new compounds isolated from sage were determined to be 6-O-caffeoyl-,-D-fructofuranosyl-(2 , 1)-,-glucopyranoside, 1-O-caffeoyl-,-D-apiofuranosyl-(1 , 6)-,-D-glucopyranoside, 1-O-p-hydroxybenzoyl-,-D-apiofuranosyl-(1 , 6)-,-D-glucopyranoside, 1-O-(3-methyl-2,3,4-trihydroxybutyl)-6-O-feruloyl-,-D-glucopyranoside, 4-hydroxyacetophenone 4-O-[5-O-(3,5-dimethoxy-4-hydroxybenzoyl)-,-D-apiofrunosyl]-(1 , 2)-,-D-glucopyranoside and 1-O-[2-hydroxy-5-(2-hydroxyethyl)phenyl]-6-O-trans-caffeoyl-,-D-glucopyranoside. [source] Study of Antimalarial Activity of Chemical Constituents from Diospyros quaesitaCHEMISTRY & BIODIVERSITY, Issue 11 2008Cui-Ying Ma Abstract Bioassay-directed fractionation led to the isolation of seven compounds from a sample of the dried leaves, twigs, and branches of Diospyros quaesitaThw. (Ebenaceae). One of the isolates, betulinic acid 3-caffeate (1), showed in vitro antimalarial activity against Plasmodium falciparum clones D6 (chloroquine-sensitive) and W2 (chloroquine-resistant) with IC50 values of 1.40 and 0.98,,M, respectively. Evaluation of compound 1 in the human oral epidermoid (KB) cancer cell line revealed cytotoxicity at ED50 of 4.0,,M. In an attempt to reduce the cytotoxicity of 1, the acetylated derivative 1a and betulinic acid (1b) were prepared. Of the seven isolates, diospyrosin (2) was determined to be a new neolignan. In addition to 1, other known compounds isolated in this study were pinoresinol, lariciresinol, N -benzoyl- L -phenylalaninol, scopoletin, and poriferast-5-en-3,,7, -diol. The structure of 2 was elucidated based on spectroscopic data analysis including 1D- and 2D-NMR, and HR-ESI-MS. [source] Neural Networks in Chemosystematic Studies of Asteraceae: A Classification Based on a Dichotomic ApproachCHEMISTRY & BIODIVERSITY, Issue 5 2005Marcelo This paper describes the application of artificial neural nets as an alternative and efficient method for the classification of botanical taxa based on chemical data (chemosystematics). A total of 28,000 botanical occurrences of chemical compounds isolated from the Asteraceae family were chosen from the literature, and grouped by chemical class for each species. Four tests were carried out to differentiate and classify different botanical taxa. The qualifying capacity of the artificial neural nets was dichotomically tested at different hierarchical levels of the family, such as subfamilies and groups of Heliantheae subtribes. Furthermore, two specific subtribes of the Heliantheae and two genera of one of these subtribes were also tested. In general, the artificial neural net gave rise to good results, with multiple-correlation values R>0.90. Hence, it was possible to differentiate the dichotomic character of the botanical taxa studied. [source] Prediction of Tyrosinase Inhibition Activity Using Atom-Based Bilinear IndicesCHEMMEDCHEM, Issue 4 2007Yovani Marrero-Ponce Prof. Abstract A set of novel atom-based molecular fingerprints is proposed based on a bilinear map similar to that defined in linear algebra. These molecular descriptors (MDs) are proposed as a new means of molecular parametrization easily calculated from 2D molecular information. The nonstochastic and stochastic molecular indices match molecular structure provided by molecular topology by using the kth nonstochastic and stochastic graph-theoretical electronic-density matrices, Mk and Sk, respectively. Thus, the kth nonstochastic and stochastic bilinear indices are calculated using Mk and Sk as matrix operators of bilinear transformations. Chemical information is coded by using different pair combinations of atomic weightings (mass, polarizability, vdW volume, and electronegativity). The results of QSAR studies of tyrosinase inhibitors using the new MDs and linear discriminant analysis (LDA) demonstrate the ability of the bilinear indices in testing biological properties. A database of 246 structurally diverse tyrosinase inhibitors was assembled. An inactive set of 412 drugs with other clinical uses was used; both active and inactive sets were processed by hierarchical and partitional cluster analyses to design training and predicting sets. Twelve LDA-based QSAR models were obtained, the first six using the nonstochastic total and local bilinear indices and the last six with the stochastic MDs. The discriminant models were applied; globally good classifications of 99.58 and 89.96,% were observed for the best nonstochastic and stochastic bilinear indices models in the training set along with high Matthews correlation coefficients (C) of 0.99 and 0.79, respectively, in the learning set. External prediction sets used to validate the models obtained were correctly classified, with accuracies of 100 and 87.78,%, respectively, yielding C values of 1.00 and 0.73. This subset contains 180 active and inactive compounds not considered to fit the models. A simulated virtual screen demonstrated this approach in searching tyrosinase inhibitors from compounds never considered in either training or predicting series. These fitted models permitted the selection of new cycloartane compounds isolated from herbal plants as new tyrosinase inhibitors. A good correspondence between theoretical and experimental inhibitory effects on tyrosinase was observed; compound CA6 (IC50=1.32,,M) showed higher activity than the reference compounds kojic acid (IC50=16.67,,M) and L -mimosine (IC50=3.68,,M). [source] | ||||||||||||||||