References of "Frederich, Michel"
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See detailFagraldehyde, a Secoiridoid Isolated from Fagraea fragrans
Jonville, Marie ULg; Capel, Marie; Frederich, Michel ULg et al

in Journal of Natural Products (2008), 71(12), 2038-2040

A secoiridoid aglycone with atypical skeleton, named fagraldehyde (1), together with several known secoiridoids (gentiopicroside (2), sweroside (3) and swertiamarin (4)) were isolated from the bark and ... [more ▼]

A secoiridoid aglycone with atypical skeleton, named fagraldehyde (1), together with several known secoiridoids (gentiopicroside (2), sweroside (3) and swertiamarin (4)) were isolated from the bark and leaves of Fagraea fragrans collected in Cambodia. The conformations of 1 were evaluated on the basis of molecular modeling and NOESY correlations. A hypothetical biogenesis of fagraldehyde was proposed to explain the unusual skeleton. Compound 1 was weakly active in vitro against Plasmodium falciparum. [less ▲]

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See detail1H NMR metabolomic approach of the laser-induced choroidal neovascularization in mice
Lambert, Vincent ULg; Frederich, Michel ULg; Rousseau, Rousseau et al

Poster (2008, August)

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See detailEthnopharmacologie et paludisme au Burkina Faso : sélection de 13 espèces à potentialités antiplasmodiales méconnues
Jansen, Olivia ULg; Frederich, Michel ULg; Tits, Monique ULg et al

in Ethnopharmacologia (2008), 41

Dans la recherche de nouvelles substances actives contre les Plasmodium, les flores non explorées du Sud constituent une source potentielle privilégiée de nouveaux médicaments antipaludéens. Dans ce ... [more ▼]

Dans la recherche de nouvelles substances actives contre les Plasmodium, les flores non explorées du Sud constituent une source potentielle privilégiée de nouveaux médicaments antipaludéens. Dans ce travail, nous avons suivi une démarche ethnopharmacologique afin de répertorier et de sélectionner des végétaux intéressants à étudier en laboratoire pour leurs propriétés antiplasmodiales. Notre travail de recensement des espèces utilisées contre la malaria au Burkina Faso nous a permis de répertorier 72 espèces végétales utilisées seules ou en association dans le traitement traditionnel du paludisme dans ce pays d’Afrique de l’Ouest. Finalement, treize espèces ont été sélectionnées et dix-sept échantillons végétaux ont été récoltés au Burkina Faso pour évaluation de leurs propriétés antiplasmodiales en laboratoire. Les principaux critères de sélection ont été : leur utilisation traditionnelle contre la malaria et le fait que ces plantes n’aient pas (ou peu) été étudiées sur le plan antiplasmodial. Les liens de chimiotaxonomie éventuels avec des plantes déjà connues pour leurs propriétés antiplasmodiales ainsi que les possibilités de valorisation des espèces au niveau local (MTA) ont également été considérés. [less ▲]

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See detailA la recherche de substances naturelles à potentialités antiplasmodiales et cytotoxiques
Frederich, Michel ULg

Scientific conference (2008, June 19)

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See detailTheoretical and Experimental Investigations of Organic Acids/Cyclodextrin Complexes and Their Consequences Upon the Formation of Miconazole/Cyclodextrin/Acid Ternary Inclusion Complexes
Barillaro, Valéry; Dive, Georges ULg; Bertholet, Pascal et al

in International Journal of Pharmaceutics (2008), 347(1-2), 62-70

(1)H NMR spectrometry, FT-IR spectroscopy, as well as molecular modeling at the AM1 level and normal mode analysis were used to characterise the interactions and the formation of inclusion complexes ... [more ▼]

(1)H NMR spectrometry, FT-IR spectroscopy, as well as molecular modeling at the AM1 level and normal mode analysis were used to characterise the interactions and the formation of inclusion complexes between three organic acids: maleic, fumaric, L-tartaric acids and betaCD. In aqueous medium, the complexation was confirmed by (1)H NMR spectroscopy using two-dimensional technique. The stable geometries of the complexes were determined by molecular modeling. Experimental infrared frequencies were assigned on the base of the vibrational normal mode calculation at the fully optimized geometry for the inclusion complexes. All the results point out the presence of stable inclusion complexes between acids and betaCD at the solid state. These results show the double role of the acid. Correlated with the theoretical and experimental data previously obtained for the miconazole/CD/acids complexes, in function of both acids and CDs structures, the acids can either stabilize the complexes by formation of a multicomponent complex or form acid/CD inclusion complexes, hindering the guest inclusion. [less ▲]

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See detailPotential antimalarial activity of indole alkaloids
Frederich, Michel ULg; Tits, Monique ULg; Angenot, Luc ULg

in Transactions of the Royal Society of Tropical Medicine & Hygiene (2008), 102(1), 11-19

New antimalarial treatments are now urgently required, following the emergence of resistance to the most used drugs. Natural products contribute greatly to the therapeutic arsenal in this area, including ... [more ▼]

New antimalarial treatments are now urgently required, following the emergence of resistance to the most used drugs. Natural products contribute greatly to the therapeutic arsenal in this area, including artemisinin and quinine (and atovaquone, semi-synthetic). Among the natural products, indole alkaloids represent an interesting class of compounds. Screening carried out to date has revealed several substances active in vitro under the micromolar range and with a good selectivity index. This review covers the indole alkaloids with high antiplasmodial activity (in vitro and in vivo) isolated from natural sources, and is organized according to the different chemical structures of the alkaloids. [less ▲]

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See detailIn vitro evaluation of antiplasmodial activity of plant samples used in traditional medicine in Benin
Ganfon, H.; Gbaguidi, F.; Frederich, Michel ULg et al

in Planta Medica (2008), 74(9), 1140-1140

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See detailEvaluation of medicinal plants from Reunion Island for antimalarial and cytotoxic activities
Jonville, Marie ULg; Kodja, H.; Humeau, L. et al

in Planta Medica (2008), 74(9), 1002-1002

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See detailIn vitro antiplasmodial activity of five plants used in Benin in traditional medicine to treat malaria
Bero, J.; Frederich, Michel ULg; De Mol, Patrick ULg et al

in Planta Medica (2008), 74(9), 1002-1002

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See detailIn vitro antiplasmodial activity of ethnobotanically selected plants from Burkina Faso
Jansen, Olivia ULg; Angenot, Luc ULg; Tits, Monique ULg et al

in Planta Medica (2008), 74(9), 1142-1142

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See detailAntiplasmodial and antitrypanosomal activity of Triclisia sacleuxii (Pierre) Diels
Murebwayire, Sangabo; Frederich, Michel ULg; Hannaert, V. et al

in Phytomedicine : International Journal of Phytotherapy and Phytopharmacology (2008), 15(9), 728-733

The antiplasmodial and antitrypanosomal activities of Triclisia sacleuxii (Pierre) Diels were investigated on three Plasmodium falciparum strains [FcB1, 3D7 (chloroquine – sensitive) and W2 (chloroquine – ... [more ▼]

The antiplasmodial and antitrypanosomal activities of Triclisia sacleuxii (Pierre) Diels were investigated on three Plasmodium falciparum strains [FcB1, 3D7 (chloroquine – sensitive) and W2 (chloroquine – resistant) strains] and on Trypanosoma brucei Tbsf 221. Roots, stems and leaves ethanolic extracts as well as crude tertiary and quaternary alkaloids fractions were considered. Whereas the ethanolic extracts and quaternary crude alkaloids fractions exhibited no significant activity, the roots and stems tertiary alkaloid fractions revealed interesting growth inhibition against the Plasmodium FcB1 and Trypanosoma Tbsf 221 strains. The IC50 were 1.04 and 0.89 g/ml (roots), 2.50 and 0.91 g/ml (stems), respectively. The leaves tertiary alkaloids fraction also showed a promising antitrypanosomal activity (IC50 : 1.85 g/ml). Phytochemical analysis of the roots tertiary alkaloids fraction yielded four major compounds, phaeanthine, N-methylapateline, 1,2-dehydroapateline and 1,2-dehydrotelobine, which were identified on the basis of their spectroscopic data. The four compounds displayed (in vitro) antitrypanosomal activity with IC50 of 2.68, 1.19, 1.06 and 1.11 µM, respectively. They also demonstrated antiplasmodial activity on Plasmodium falciparum 3D7, with IC50 of 1.72, 0.93, 1.39 and 12.4 µM respectively and on the chloroquine – resistant W2 with IC50 of 0.35, 1.10, 1.63, 1.52 µM. [less ▲]

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See detailScreening of medicinal plants from Reunion Island for antimalarial and cytotoxic activity.
Jonville, Marie ULg; Kodja, H.; Humeau, L. et al

in Journal of Ethnopharmacology (2008), 120(3), 382-6

AIM OF THE STUDY: Nine plants from Reunion Island, selected using ethnopharmacology and chemotaxonomy, were investigated for their potential antimalarial value. MATERIALS AND METHODS: Thirty-eight ... [more ▼]

AIM OF THE STUDY: Nine plants from Reunion Island, selected using ethnopharmacology and chemotaxonomy, were investigated for their potential antimalarial value. MATERIALS AND METHODS: Thirty-eight extracts were prepared by maceration using CH(2)Cl(2) and MeOH, and were tested for in vitro activity against the 3D7 and W2 strain of Plasmodium falciparum. The most active extracts were then tested for in vitro cytotoxicity on human WI-38 fibroblasts to determine the selectivity index. Those extracts were also investigated in vivo against Plasmodium berghei infected mice. RESULTS: Most active of the extracts tested were the dichloromethane leaves extracts of Nuxia verticillata Lam. (Buddlejaceae), Psiadia arguta Voigt. (Asteraceae), Lantana camara L. (Verbenaceae), the methanol extracts from Aphloia theiformis (Vahl) Benn. (Aphloiaceae) bark, and Terminalia bentzoe L. (Combretaceae) leaves displaying in vitro IC(50) values ranging from 5.7 to 14.1mug/ml. Extracts from Psiadia, Aphloia at 200mg/(kgday) and Teminalia at 50mg/(kgday) also exhibited significant (p<0.0005) parasite inhibition in mice: 75.5%, 65.6% and 83.5%, respectively. CONCLUSION: Two plants showed interesting antimalarial activity with good selectivity: Aphloia theiformis and Terminalia bentzoe. Nuxia verticillata still needs to be tested in vivo, with a new batch of plant material. [less ▲]

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See detailA la recherche de substances naturelles antiplasmodiales et cytotoxiques
Frederich, Michel ULg

Scientific conference (2007, December 10)

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See detailIn vitro cytotoxicity of some medicinal plants from Georgian amaryllidaceae
Jokhadze, Malkhaz; Eristavi, Lina; Kutchukhidze, Jumber et al

in Phytotherapy Research (2007), 21(7), 622-624

Using an ethnomedical data approach, some Georgian plants, which are used in Georgian traditional medicine for cancer or non-cancer diseases, were collected and evaluated for cytotoxic activity. The ... [more ▼]

Using an ethnomedical data approach, some Georgian plants, which are used in Georgian traditional medicine for cancer or non-cancer diseases, were collected and evaluated for cytotoxic activity. The cytotoxic effect of the methanol extracts of species from the genera Galanthus and Leucojum was evaluated in vitro on three human cell lines (Hela, ephitheloid cervix carcinoma; HCT-116, colon carcinoma; HL-60, acute myeloid leukaemia). Cell type cytotoxic specificity was observed for some extracts. Overall, the HCT-116 cells were much more sensitive to most of the extracts than were the other cell lines. Plants that showed pronounced cytotoxic activity will be further evaluated for the possible isolation of active antitumour compounds. Copyright (C) 2007 John Wiley [less ▲]

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See detailIn vivo antimalarial activity of isosungucine, an indolomonoterpenic alkaloid from Strychnos icaja
Philippe, Geneviève ULg; De Mol, Patrick ULg; Angenot, Luc ULg et al

in Planta Medica (2007), 73(5), 478-479

Isosungucine (1) is a quasi-symmetric bisindolomonoterpenoid alkaloid isolated from the roots of Strychnos icaja. The in vivo antimalarial activity against the P. vinckei petteri murine strain was ... [more ▼]

Isosungucine (1) is a quasi-symmetric bisindolomonoterpenoid alkaloid isolated from the roots of Strychnos icaja. The in vivo antimalarial activity against the P. vinckei petteri murine strain was determined. In the Peters 4-day suppressive test, 1 suppressed the parasitemia by almost 50 percent on day 4 at the dose of 30 mg/kg by intraperitoneal route. [less ▲]

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See detailStudy of the physicochemical properties in aqueous medium and molecular modeling of tagitinin C/cyclodextrin complexes
Ziemons, Eric ULg; Dive, Georges ULg; Debrus, Benjamin ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (2007), 43(3), 910-919

The inclusion complexes of tagitinin C with beta-, 2,6-di-O-methyl-beta- and gamma-cyclodextrin (CyD) was investigated in aqueous medium. The stoichiometric ratios and stability constants (K(f)) which ... [more ▼]

The inclusion complexes of tagitinin C with beta-, 2,6-di-O-methyl-beta- and gamma-cyclodextrin (CyD) was investigated in aqueous medium. The stoichiometric ratios and stability constants (K(f)) which describe the extent of formation of the complexes have been determined by UV spectroscopy and direct current tast polarography (DC(tast)), respectively. For each complex, a 1:1 molar ratio was formed in solution and the trend of stability constants was K(f) (2,6-di-O-methyl-beta-CyD)>K(f) (gamma-CyD)>K(f) (beta-CyD). The effect of molecular encapsulation on the photochemical conversion of tagitinin C was evaluated. No significant protection efficacy was noticed with beta- and gamma-CyD for the complexed drug with the respect to the free one. On the other hand, the photochemical conversion rate was slowed in presence of 2,6-di-O-methyl-beta-CyD. Data from (1)H NMR and ROESY experiments provided a clear evidence of formation of inclusion complexes. The lactone, the ester and the unsaturated ketone parts of tagitinin C inserted into the wide rim of the CyDs torus. These experimental results were confirmed by the molecular modeling using semiempirical Austin Model 1 (AM1) method. [less ▲]

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