In vitro antiplasmodial activity of Tithonia diversifolia and identification of its main active constituent: tagitinin C.Goffin, Eric ; Ziemons, Eric ; De Mol, Patrick et alin Planta Medica (2002), 68(6), 543-5 The antimalarial properties of Tithonia diversifolia, an Asteraceae traditionally used to treat malaria, were investigated in vitro against three strains of Plasmodium falciparum. The ether extract from ... [more ▼] The antimalarial properties of Tithonia diversifolia, an Asteraceae traditionally used to treat malaria, were investigated in vitro against three strains of Plasmodium falciparum. The ether extract from aerial parts of the plant collected in Sao Tome e Principe, demonstrated good antiplasmodial activity (IC 50 on FCA strain: 0.75 microg/ml). A bioassay guided fractionation of this extract led to the isolation of the known sesquiterpene lactone tagitinin C as an active component against Plasmodium (IC 50 on FCA strain: 0.33 microg/ml), but also possessing cytotoxic properties (IC 50 on HTC-116 cells: 0.706 microg/ml). [less ▲] Detailed reference viewed: 116 (10 ULg) Strychnohexamine from Strychnos icaja, a naturally occurring trimeric indolomonoterpenic alkaloidPhilippe, Geneviève ; ; et alin Tetrahedron Letters (2002), 43(18), 3387-3390 A reinvestigation of Strychnos icaja roots has resulted in the isolation, from the EtOAC extract, of one tertiary trisindole alkaloid, named strychnohexamine. Its structure has been investigated by means ... [more ▼] A reinvestigation of Strychnos icaja roots has resulted in the isolation, from the EtOAC extract, of one tertiary trisindole alkaloid, named strychnohexamine. Its structure has been investigated by means of spectroscopic data interpretation (UV. IR. HRESIMS. 1D and 2D NMR). This is the first time that a natural trimeric indolomonoterpenic alkaloid has been isolated directly from a plant species. This compound is one of the largest alkaloids ever discovered. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲] Detailed reference viewed: 34 (10 ULg) Isolation and pharmacological activity of phenylpropanoid esters from Marrubium vulgare; Garbacki, Nancy ; Tits, Monique et alin Journal of Ethnopharmacology (2002), 79(3), 389-392 The isolation and identification of major phenylpropanoid esters from Marrubium vulgare: (+) (E)-caffeoyl-L-malic acid 1, acteoside 2, forsythoside B 3, arenarioside 4, ballotetroside 5, as well as their ... [more ▼] The isolation and identification of major phenylpropanoid esters from Marrubium vulgare: (+) (E)-caffeoyl-L-malic acid 1, acteoside 2, forsythoside B 3, arenarioside 4, ballotetroside 5, as well as their anti-inflammatory activity are reported for the first time, We evaluated the inhibitory effects of these five compounds on cyclooxygenase (Cox) catalysed prostaglandin biosynthesis activity. Only the glycosidic phenylpropanoid esters showed an inhibitory activity towards the Cox-2 enzyme and three of them: acteoside 2, forsythoside B 3, arenarioside 4, exhibited higher inhibitory potencies on Cox-2 than on Cox-1. These results are of interest, as Cox-2 is mainly associated with inflammation and the Cox-1 inhibition with adverse side effects often observed with non-steroidal anti-inflammatory drugs. The occurence of these phenylpropanoid esters could also explain some other pharmacological properties of M. vulgare. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved. [less ▲] Detailed reference viewed: 58 (1 ULg) New 3-deoxyanthocyanidins from leaves of Arrabidaea chica; Llabres, Gabriel ; et alin Phytochemical Analysis [=PCA] (2002), 13(2, Mar-Apr), 114-120 Two new 3-deoxyanthocyanidins, 6,7,3',4'-tetrahydroxy-5-methoxyflavylium and 6,7,4'-trihydroxy-5-methoxyflavylium, and the pigment carajurin, which has been previously identified, were isolated from dried ... [more ▼] Two new 3-deoxyanthocyanidins, 6,7,3',4'-tetrahydroxy-5-methoxyflavylium and 6,7,4'-trihydroxy-5-methoxyflavylium, and the pigment carajurin, which has been previously identified, were isolated from dried leaves of Arrabidaea chica, a creeper native to the American tropics. The structures of the components were elucidated by H-1- and C-13-NMR spectroscopy and HPLC-MS, including X-ray crystallographic analysis for carajurin. Copyright (C) 2002 John Wiley Sons, Ltd. [less ▲] Detailed reference viewed: 37 (3 ULg) In vivo investigation of the anti-inflammatory activity of proanthocyanidins from Ribes nigrum leaves.Garbacki, Nancy ; Tits, Monique ; Angenot, Luc et alPoster (2002) Detailed reference viewed: 9 (1 ULg) Tagitinin C from Tithonia diversifolia : anti-inflammatory activity and high performance liquid chromatogaphic quantification.Goffin, Eric ; Garbacki, Nancy ; Damas, Jacques et alPoster (2002) Detailed reference viewed: 23 (2 ULg) 5',6'-Dehydroguiachrysine and 5',6'-Dehydroguiaflavine, Two Curarizing Quaternary Indole Alkaloids from the Stem Bark of Strychnos Guianensis; ; et al in Phytochemistry (2001), 58(4), 619-26 Two new quaternary indole alkaloids 5',6'-dehydroguiachrysine (1) and 5',6'-dehydroguiaflavine (2) were isolated from Strychnos guianensis stem bark. Their structures were determined by analysis of ... [more ▼] Two new quaternary indole alkaloids 5',6'-dehydroguiachrysine (1) and 5',6'-dehydroguiaflavine (2) were isolated from Strychnos guianensis stem bark. Their structures were determined by analysis of spectral data. Their inhibitory effects on neuromuscular transmission are also reported and compared to that of other quaternary alkaloids. [less ▲] Detailed reference viewed: 8 (2 ULg) Reversal of Chloroquine and Mefloquine Resistance in Plasmodium Falciparum by the Two Monoindole Alkaloids, Icajine and IsoretulineFrederich, Michel ; Hayette, Marie-Pierre ; Tits, Monique et alin Planta Medica (2001), 67(6), 523-7 Eight naturally occurring monoindole alkaloids were evaluated in vitro for their ability to inhibit Plasmodium falciparum growth and, in drug combination, to reverse the resistance of a chloroquine ... [more ▼] Eight naturally occurring monoindole alkaloids were evaluated in vitro for their ability to inhibit Plasmodium falciparum growth and, in drug combination, to reverse the resistance of a chloroquine-resistant strain of Plasmodium falciparum. None of these indole alkaloids has significant intrinsic antiplasmodial activity (IC(50) > 10 microM or 5 microg/ml). Nevertheless, three alkaloids (icajine, isoretuline and strychnobrasiline) did reverse chloroquine resistance at concentrations between 2.5 and 25 microg/ml (IF of 12.82 for isoretuline on W2 strain). The Interaction Factor (IF) equals 2, < 2, or > 2 for additive, antagonistic or synergistic effects of alkaloids on chloroquine inhibition, respectively. Icajine and isoretuline were also assessed in vitro for their mefloquine potentiating activity on a mefloquine-resistant strain of Plasmodium falciparum. Only icajine proved to be synergistic with mefloquine (IF = 15.38). [less ▲] Detailed reference viewed: 35 (3 ULg) Main Glucosidase Conversion Products of the Gluco-Alkaloids Dolichantoside and Palicoside; Tits, Monique ; et alin Phytochemistry (2001), 57(5), 653-9 The enzymatic glucose cleavage of palicoside revealed the biosynthetic pathway to akagerine, whereas the conversion of dolichantoside led to a new quaternary heteroyohimbine alkaloid named N(b)-methyl-21 ... [more ▼] The enzymatic glucose cleavage of palicoside revealed the biosynthetic pathway to akagerine, whereas the conversion of dolichantoside led to a new quaternary heteroyohimbine alkaloid named N(b)-methyl-21-beta-hydroxy-mayumbine. The hypothetical models of reactions occurring after the conversion of both substrates are proposed. Dolichantoside and palicoside, as well as Strychnos mellodora stem bark crude ethanol extract, exhibit significant antimycotic activity against human pathogens in presence of specific glucosidase. [less ▲] Detailed reference viewed: 18 (1 ULg) Strychnogucines a and B, Two New Antiplasmodial Bisindole Alkaloids from Strychnos IcajaFrederich, Michel ; Gillet, Marie-Claire ; Prosperi, Christelle et alin Journal of Natural Products (2001), 64(1), 12-16 A reinvestigation of Strychnos icaja roots has resulted in the isolation of two tertiary quasi-symmetric bisindole alkaloids named strychnogucines A (1) and B (2). Their structures were identified by ... [more ▼] A reinvestigation of Strychnos icaja roots has resulted in the isolation of two tertiary quasi-symmetric bisindole alkaloids named strychnogucines A (1) and B (2). Their structures were identified by means of spectroscopic data interpretation. Compound 2 was highly active in vitro and compound 1 moderately active against four strains of Plasmodium falciparum. Strychnogucine B (2) was more active against a chloroquine-resistant strain than against a chloroquine-sensitive one (best CI(50), 80 nM against the W2 strain). In addition, this compound showed a selective antiplasmodial activity with 25-180 times greater toxicity toward P. falciparum, relative to cultured human cancer cells (KB) or human fibroblasts (WI38). [less ▲] Detailed reference viewed: 45 (7 ULg) Anti-inflammatory effects of Centaurea cyanus (Asteraceae) flower-heads.Garbacki, Nancy ; ; Damas, Jacques et alPoster (2001) Detailed reference viewed: 10 (0 ULg) Polyphénols du Marrube (Marrubium vulgare L.) et évaluation de l'activité anti-inflammatoire sur Cox-1 et Cox-2.; Garbacki, Nancy ; Tits, Monique et alPoster (2001) Detailed reference viewed: 57 (0 ULg) Etude du mécanisme d’action d’alcaloides bisindoliques, isolés du Strychnos icaja, à potentialité anticancéreuseGillet, Marie-Claire ; Frederich, Michel ; Tits, Monique et alPoster (2000, July) Detailed reference viewed: 11 (0 ULg) Inhibition of Croton Oil-Induced Oedema in Mice Ear Skin by Capsular Polysaccharides from CyanobacteriaGarbacki, Nancy ; ; Damas, Jacques et alin Naunyn-Schmiedeberg's Archives of Pharmacology (2000), 361(4), 460-4 The anti-inflammatory properties of hydrophilic extracts of the capsular polymers of twelve cyanobacterial strains belonging to the genera Phormidium and Nostoc from marine and terrestrial habitats were ... [more ▼] The anti-inflammatory properties of hydrophilic extracts of the capsular polymers of twelve cyanobacterial strains belonging to the genera Phormidium and Nostoc from marine and terrestrial habitats were tested topically on croton oil-induced oedema in mice ear skin. The screening program identified several strains as producers of anti-inflammatory products (up to 56% inhibition of the oedema). The inhibition response was dose-dependent. The application of trichloroacetic acid-treated extracts reduced the oedema by about 60%. On the other hand, one of the strains enhanced the inflammatory response. Analysis of five of the extracts showed the presence of neutral sugars (from 34.3% to 47.1%, w/w), uronic acids (from 7.1% to 26.7%, w/w) and proteins (from 30.1% to 57.0%, w/w) in the crude polymer. Rhamnose, fucose, arabinose, xylose, mannose, glucose, galactose, galacturonic acid and glucuronic acid were detected as well as sulphate groups (from 9.6% to 21.5%, w/w of sugars). The main components found were glucose and mannose. [less ▲] Detailed reference viewed: 32 (3 ULg) Quaternary Indole Alkaloids from the Stem Bark of Strychnos Guianensis; Tits, Monique ; et alin Phytochemistry (2000), 53(8), 1057-66 Two new quaternary alkaloids, 9-methoxy-Nb-methylgeissoschizol and guiachrysine together with the known compounds C-alkaloid O, fluorocurine, mavacurine, macusine B and C-profluorocurine, were isolated ... [more ▼] Two new quaternary alkaloids, 9-methoxy-Nb-methylgeissoschizol and guiachrysine together with the known compounds C-alkaloid O, fluorocurine, mavacurine, macusine B and C-profluorocurine, were isolated from Strychnos guianensis stembark. The structures of the compounds were elucidated on the basis of spectroscopic studies. [less ▲] Detailed reference viewed: 25 (4 ULg) New Antimalarial and Cytotoxic Sungucine Derivatives from Strychnos Icaja RootsFrederich, Michel ; Gillet, Marie-Claire ; Llabres, Gabriel et alin Planta Medica (2000), 66(3), 262-9 Reinvestigation of Strychnos icaja Baillon resulted in the isolation of vomicine, isostrychnine and of three new sungucine derivatives, named isosungucine (8), 18-hydroxy-sungucine (9) and 18-hydroxy ... [more ▼] Reinvestigation of Strychnos icaja Baillon resulted in the isolation of vomicine, isostrychnine and of three new sungucine derivatives, named isosungucine (8), 18-hydroxy-sungucine (9) and 18-hydroxy-isosungucine (10). They were identified by detailed spectroscopic methods. The complete 1H- and 13C-NMR study of sungucine was also realized. Some of these compounds were highly active against Plasmodium falciparum in vitro and more particularly against the chloroquine-resistant strain. Compound 10 showed a selective antiplasmodial activity, with > 100-fold greater toxicity towards Plasmodium falciparum, relative to cultured human cancer cells (KB and HeLa lines) or fibroblasts (WI38). [less ▲] Detailed reference viewed: 42 (13 ULg) New strictosidine beta-glucosidase from Strychnos mellodora; ; Tits, Monique et alin Plant Physiology & Biochemistry (2000), 38(3), 187-192 A stable strictosidine glucosidase was isolated from dried powdered material of Strychnos mellodora. The kinetic parameters Km and Vmax of the purified glucosidases from catharanthus roseus and S ... [more ▼] A stable strictosidine glucosidase was isolated from dried powdered material of Strychnos mellodora. The kinetic parameters Km and Vmax of the purified glucosidases from catharanthus roseus and S. mellodora towards strictosidine, dolichantoside and palicoside were determined and compared. [less ▲] Detailed reference viewed: 28 (2 ULg) Evaluation de l'activité anti-inflammatoire sur COX-1 et COX-2 de l'actéoside et de plantes médicinales en contenant.Garbacki, Nancy ; ; Tits, Monique et alPoster (2000) Detailed reference viewed: 53 (0 ULg) Anti-inflammatory and chondroprotective activity of prodelphinidins isolated from Ribes nigrum leaves.Tits, Monique ; ; et alPoster (2000) Detailed reference viewed: 13 (0 ULg) Anti-Inflammatory and Immunological Effects of Centaurea Cyanus Flower-HeadsGarbacki, Nancy ; ; Damas, Jacques et alin Journal of Ethnopharmacology (1999), 68(1-3), 235-41 Centaurea cyanus flower-heads are used in European phytotherapy for the treatment of minor ocular inflammations. Different pharmacological experiments (inhibition of carrageenan, zymosan and croton oil ... [more ▼] Centaurea cyanus flower-heads are used in European phytotherapy for the treatment of minor ocular inflammations. Different pharmacological experiments (inhibition of carrageenan, zymosan and croton oil-induced oedemas, inhibition of plasma haemolytic activity, induction of anaphylatoxin activity) showed that polysaccharides extracted from C. cyanus flower-heads had anti-inflammatory properties and interfered with complement. Moreover, these polysaccharides were found to be mainly composed of galacturonic acid, arabinose, glucose, rhamnose and galactose. [less ▲] Detailed reference viewed: 66 (3 ULg) |
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