References of "Frederich, Michel"
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See detailPharmacognosie - Volume 2
Angenot, Luc ULg; Tits, Monique ULg; Frederich, Michel ULg

Learning material (2010)

Le volume 2 est consacré aux grands classiques de la pharmacognosie dont ont été isolés de très nombreux principes actifs (souvent des alcaloïdes) qui ont marqué l'histoire de la pharmacie et de la ... [more ▼]

Le volume 2 est consacré aux grands classiques de la pharmacognosie dont ont été isolés de très nombreux principes actifs (souvent des alcaloïdes) qui ont marqué l'histoire de la pharmacie et de la pharmacologie.Les chapitres suivants seront abordés: analgésiques (pavot,opium, colchique...); Solanacées à activité parasympatholytiques ( belladone, stramoine, jusquiames...); dérivés de l'ergot de seigle; médicaments des troubles cérébraux de la sénescence ( ginkgo, amaryllidacées à galanthamine...); drogues alcaloïdiques psychoactives ( coca, éphédra, khat, psilocybes, peyotl, harmel, yagé, iboga...); hallucinogènes non alcaloïdiques ( cannabis, sauge des devins..); poisons agissant sur la neurotransmission :cholinergiques ( jaborandi, éséré...), paralysants neuro-musculaires (curares) et antagonistes de la glycine ( noix-vomique); antiparasitaires (malaria et amibiase): quinquinas, armoises, ipécas; anticancéreux : lignanes ( Podophyllum), diterpènes des ifs (Taxus sp), alcaloïdes indoliques ( Catharanthus roseus, Camptotheca ...), divers ( origine marine, épices...); plantes toxiques de l'environnement ( toxicité par contact ou par ingestion) [less ▲]

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See detailPharmacognosie Volume 3
Angenot, Luc ULg; Tits, Monique ULg; Frederich, Michel ULg

Learning material (2010)

Le volume 3 est principalement consacré à la phytothérapie (intérêt et limites) avec des notions concernant aussi bien la médecine traditionnelle que les développements les plus récents ( y compris pour ... [more ▼]

Le volume 3 est principalement consacré à la phytothérapie (intérêt et limites) avec des notions concernant aussi bien la médecine traditionnelle que les développements les plus récents ( y compris pour certains s'appuyant sur des études cliniques) en matière de phytomédicaments. La classification se fait suivant les activités pharmacologiques de ces plantes. Au terme de ce cours, les étudiants doivent pouvoir faire la distinction entre les différentes formes pharmaceutiques à base de produits d'origine naturelle ( poudres, extraits sec et autres), les concentrations en principes actifs et traceurs y étant bien différentes. Les différences entre les médicaments enregistrés et les compléments alimentaires sont également bien mises en évidence car les exigences relatives au contrôle de qualité et à la stabilité des produits finis sont très différentes. A ce sujet l'annexe du volume 3 est consacrée au contrôle de qualité des plantes en insistant sur les méthodes et monographies de la pharmacopée européenne qui joue un rôle essentiel dans ce domaine. [less ▲]

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See detailMetabolomic analysis of Echinacea spp. by (1)H nuclear magnetic resonance spectrometry and multivariate data analysis technique.
Frederich, Michel ULg; Jansen, C.; De Tullio, Pascal ULg et al

in Phytochemical Analysis (2010), 21(1), 61-65

Introduction - The genus Echinacea (Asteraceae) comprises about 10 species originally distributed in North America. Three species are very well known as they are used worldwide as medicinal plants ... [more ▼]

Introduction - The genus Echinacea (Asteraceae) comprises about 10 species originally distributed in North America. Three species are very well known as they are used worldwide as medicinal plants: Echinacea purpurea, E. pallida, E. angustifolia.Objective - To discriminate between these three Echinacea species and E. simulata by (1)H NMR-based metabolomics.Methodology - (1)H NMR and multivariate analysis techniques were applied to diverse Echinacea plants including roots and aerial parts, authentic plants, commercial plants and commercial dry extracts.Results - Using the (1)H NMR metabolomics, it was possible, without previous evaporation or separation steps, to obtain a metabolic fingerprint to distinguish between species.Conclusion - A clear distinction between the three pharmaceutical species was possible and some useful metabolites were identified. Copyright (c) 2009 John Wiley & Sons, Ltd. [less ▲]

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See detailMolecular biology, phytochemistry and bioactivity of three endemic Aloe species from Mauritius and Reunion Islands.
Ranghoo-Sanmukhiya, M.; Govinden-Soulange, J.; Lavergne, C. et al

in Phytochemical Analysis (2010)

Introduction - Aloe tormentorii, A. purpurea and A. macra are used as multipurpose folk medicines in Reunion and Mauritius Islands and are mistaken for the introduced Aloe vera.Objective - To compare the ... [more ▼]

Introduction - Aloe tormentorii, A. purpurea and A. macra are used as multipurpose folk medicines in Reunion and Mauritius Islands and are mistaken for the introduced Aloe vera.Objective - To compare the phytochemical, antimicrobial and DNA profiles of Aloe endemic to Mauritius and Reunion with the profiles of A. vera.Methodology - Leaf extracts of these Aloe species were analysed using standard phytochemical screening techniques, TLC and by HPLC. These extracts were also assayed for antimicrobial activity using microdilution techniques. Genetic diversity was studied using RAPD markers.Results - Phytochemical and antimicrobial assays and RAPD analysis showed that Mascarene Aloe species were very different from A. vera.Conclusion - This study is the first report highlighting the differences between Aloe sp.p from Mascarene and Aloe vera at the metabolic and genomic level. Copyright (c) 2010 John Wiley & Sons, Ltd. [less ▲]

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See detailCoupling of Liquid Chromatography/Tandem Mass Spectrometry and Liquid Chromatography/Solid-Phase Extraction/NMR Techniques for the Structural Identification of Metabolites following In Vitro Biotransformation of SUR1-Selective ATP-Sensitive Potassium Channel Openers
Gillotin, F.; Chiap, Patrice ULg; Frederich, Michel ULg et al

in Drug Metabolism and Disposition : The Biological Fate of Chemicals (2010), 38(2), 232-240

SUR1-selective ATP-sensitive potassium channel openers (PCOs) have been shown to be of clinical value for the treatment of several metabolic disorders, including type I and type II diabetes, obesity and ... [more ▼]

SUR1-selective ATP-sensitive potassium channel openers (PCOs) have been shown to be of clinical value for the treatment of several metabolic disorders, including type I and type II diabetes, obesity and hyperinsulinemia. Taking into account these promising therapeutic benefits, different series of 3-alkylamino-4H-1,2,4-benzothiadiazine 1,1-dioxides structurally related to diazoxide were developed. In view of the lead optimisation process of the series, knowledge of ADMET parameters, and more particularly the metabolic fate of these compounds, is a fundamental requirement. For such a purpose, two selected promising compounds (BPDZ 73 and BPDZ 157) were incubated in the presence of phenobarbital-induced rat liver microsomes to produce expected mammal in vivo phase I metabolites. The resulting major metabolites were then analysed by both MS and NMR in order to completely elucidate their chemical structures. The two compounds were also further incubated in the presence of non-treated rats and human microsomes in order to compare the metabolic profiles. In the present study, the combined use of an exact mass LC-MS/MS platform and a LC-SPE-NMR system allowed the clarification of some unresolved structural assessments in the accurate chemical structure elucidation process of the selected PCOs drugs. These results greatly help the optimization of the lead compounds. [less ▲]

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See detailMoandaensine, a dimeric indole alkaloid from Strychnos moandaensis (Loganiaceae)
Verpoorte, Robert; Frederich, Michel ULg; Delaude, Clément et al

in Phytochemistry Letters (2010), 3

Moandaensine contains a rare anhydronium base subunit. It presents a moderate antiplasmodial activity with IC values of 11.2 microM and 9.2 microM against , respectively, the chloroquino sensitive FCA 20 ... [more ▼]

Moandaensine contains a rare anhydronium base subunit. It presents a moderate antiplasmodial activity with IC values of 11.2 microM and 9.2 microM against , respectively, the chloroquino sensitive FCA 20 GHA and chloroquino resistant W2 strains of Plasmodium falciparum [less ▲]

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See detailAntiplasmodial and cytotoxic activities of Rwandan medicinal plants used in the treatment of malaria.
Muganga, R.; Angenot, Luc ULg; Tits, Monique ULg et al

in Journal of Ethnopharmacology (2010), 128

AIM OF THE STUDY: In our study, methanol, dichloromethane and aqueous extracts of 13 Rwandan medicinal plants used in the treatment of malaria were tested for in vitro antiplasmodial activity. MATERIALS ... [more ▼]

AIM OF THE STUDY: In our study, methanol, dichloromethane and aqueous extracts of 13 Rwandan medicinal plants used in the treatment of malaria were tested for in vitro antiplasmodial activity. MATERIALS AND METHODS: The growth inhibition of chloroquine-sensitive Plasmodium falciparum strain (3D7) was evaluated using the measurement of lactate dehydrogenase activity. The active extracts were also tested against the chloroquine-resistant Plasmodium falciparum strain (W2) and for cytotoxicity assay using human normal foetal lung fibroblasts (WI-38). RESULTS: The majority of the plants tested showed an antiplasmodial activity and the best results were observed with dichloromethane leaf and flower extracts of Tithonia diversifolia, leaf extract of Microglossa pyrifolia and root extract of Rumex abyssinicus, methanol leaf extract of Fuerstia africana, root bark extracts of Zanthoxylum chalybeum and methanol bark extract of Terminalia mollis. Those extracts were active (IC(50)<15mug/ml) on both chloroquine-sensitive and resistant strains of Plasmodium falciparum. Zanthoxylum chalybeum, Solanecio mannii and Terminalia mollis presented the best selectivity index. CONCLUSIONS: The traditional use of most of the plant evaluated was confirmed by the antiplasmodial test. This study revealed for the first time the antiplasmodial activity of two plants: Terminalia mollis and Rumex abyssinicus. [less ▲]

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See detailIsostrychnopentamine, an Indolomonoterpenic Alkaloid from Strychnos usambarensis, with Potential Antitumor Activity against Apoptosis-Resistant Cancer Cells
Balde, El-Hadj Saidou; Mégalizzi, Véronique; Angenot, Luc ULg et al

in International Journal of Oncology (2010), 36

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See detailSpectroscopic studies and molecular modeling for understanding the interactions between cholesterol and cyclodextrins
Castagne, Delphine ULg; Dive, Georges ULg; Evrard, Brigitte ULg et al

in Journal of Pharmacy & Pharmaceutical Sciences : A Publication of the Canadian Society for Pharmaceutical Sciences (2010), 13(2), 362-377

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See detailEvaluation of 13 selected medicinal plants from Burkina Faso for their antiplasmodial properties.
Jansen, Olivia ULg; Angenot, Luc ULg; Tits, Monique ULg et al

in Journal of Ethnopharmacology (2010), 130

AIM OF THE STUDY: The aim of this study was to evaluate the antiplasmodial properties of 13 plants used against malaria in traditional medicine in Burkina Faso. MATERIALS AND METHODS: In vitro ... [more ▼]

AIM OF THE STUDY: The aim of this study was to evaluate the antiplasmodial properties of 13 plants used against malaria in traditional medicine in Burkina Faso. MATERIALS AND METHODS: In vitro antiplasmodial activity of dichloromethane, methanol and aqueous crude extracts obtained from vegetal samples collected in Burkina Faso was first evaluated on the Plasmodium falciparum 3D7 chloroquine-sensitive strain using a colorimetric method. RESULTS: Thirteen extracts obtained from 8 different species were found to exhibit antiplasmodial activity (IC(50)<50mug/ml). Five species demonstrated a moderate activity (15mug/ml<IC(50)<50mug/ml): Boswellia dalzielii (leaves), Waltheria indica (roots and aerial parts), Bergia suffruticosa (whole plant), Vitellaria paradoxa (bark) and Jatropha gossypiifolia (leaves). The best results were obtained with extracts from the Dicoma tomentosa whole plant, from Psorospermum senegalense leaves and from Gardenia sokotensis leaves. These extracts found to display promising antiplasmodial activity, with IC(50) values ranging from 7.0 to 14.0mug/ml. The most active plant extracts were then tested for in vitro activity on the Plasmodium falciparum W2 chloroquine-resistant strain and also for in vitro cytotoxicity on normal human fibroblasts (WI-38) in order to determine the selectivity index. CONCLUSIONS: Dicoma tomentosa (Asteraceae) and Psorospermum senegalense (Clusiaceae) appeared to be the best candidates for further investigation of their antiplasmodial properties, reported for the first time by this study. [less ▲]

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See detailMetabolomic investigation of the ethnopharmacological use of Artemisia afra with NMR Spectroscopy and Multivariate Data Analysis.
Liu, N. Q.; Cao, Martine ULg; Frederich, Michel ULg et al

in Journal of Ethnopharmacology (2010), 128

Ethnopharmacological relevance: Artemisia afra has been used as an infusion to treat malaria throughout the southern parts of Africa, in much the same way as the antimalarial plant Artemisia annua in ... [more ▼]

Ethnopharmacological relevance: Artemisia afra has been used as an infusion to treat malaria throughout the southern parts of Africa, in much the same way as the antimalarial plant Artemisia annua in China. The antiplasmodial activity of purified components from an apolar fraction of A. afra has been shown in the past. No data on the efficacy of the tea infusion prepared from A. afra are however available. OBJECTIVE: To investigate the antiplasmodial activity of various extracts of A. afra including an ethnopharmacological prepared sample. To identify polar metabolites in A. afra and A. annua and by using multivariate data analysis investigate the metabolic differences between these species. Materials and methods: The antiplasmodial activity of A. afra and A. annua extracts were tested for activity against Plasmodiam falciparum 3D7 (chloroquine-sensitive strain) with chloroquine, quinine and artemisinin as positive controls. Hydrophilic metabolites in A. afra and A. annua were identified directly from the crude extracts through 1D- and 2D-NMR spectra. The NMR spectra were also used to differentiate between the two species using principal component analysis (PCA) for quality control purposes. RESULTS: The apolar fractions of both A. afra and A. annua showed activity against P. falciparum while activity was only found in the tea infusion of A. annua. Metabolomic studies using 1D- and 2D-NMR spectroscopy identified 24 semi-polar components in A. afra including three new phenylpropanoids for this species: caffeic acid, chlorogenic acid and 3,5-dicaffeoyl quinic acid. PCA analysis conducted on the samples yielded good separation between the polar extracts of A. afra and A. annua. CONCLUSION: These findings shows that there are no in vitro activity in the tea infusion of A. afra and lists the identified metabolites causing the metabolic differences between A. afra and A. annua for quality control purposes. [less ▲]

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See detailIn vitro and in vivo antimalarial and cytotoxic activity of five plants used in Congolese traditional medicine.
Lusakibanza, M.; Mesia, G.; Tona, G. et al

in Journal of Ethnopharmacology (2010), 129

AIM OF THE STUDY: The in vitro antiplasmodial activity and cytotoxicity of methanolic and dichloromethane extracts from five Congolese plants were evaluated. The plants were selected following an ... [more ▼]

AIM OF THE STUDY: The in vitro antiplasmodial activity and cytotoxicity of methanolic and dichloromethane extracts from five Congolese plants were evaluated. The plants were selected following an ethnobotanical survey conducted in D.R. Congo and focusing on plants used traditionally to treat malaria. The in vivo antimalarial activity of aqueous and methanolic extracts active in vitro was also determined in mice infected by Plasmodium berghei berghei. MATERIALS AND METHODS: The growth inhibition of Plasmodium falciparum strains was evaluated using the measurement of lactate dehydrogenase activity. The extracts (aqueous, CH(3)OH, EtOH and CH(2)Cl(2)) were prepared by maceration and tested in vitro against the 3D7 (chloroquine sensitive) and W2 (chloroquine resistant) strains of Plasmodium falciparum and against the human normal fetal lung fibroblasts WI-38 to determine the selectivity index. Some extracts were also used at the dose of 300mg/kg to evaluate their activity in mice infected since 4 days by Plasmodium berghei. RESULTS: Two plants presented a very high activity (IC(50)<3mug/ml). These plants were Strychnos icaja roots bark (MeOH and CH(2)Cl(2)) and Physalis angulata leaves (MeOH and CH(2)Cl(2)). One plant (Anisopappus chinensis whole plant, MeOH and CH(2)Cl(2)) presented a high activity (IC50<15mug/ml). The extracts of Anisopappus chinensis and Physalis angulata showed also a good inhibition of parasitemia in vivo. Flavonoids, phenolic acids and terpenes were identified in these plants by a general phytochemical screening method. CONCLUSION: Three plants showed a very interesting antiplasmodial activity (Anisopappus chinensis, Physalis angulata and Strychnos icaja) and one of them showed a good selectivity index (>10, Anisopappus chinensis). Anisopappus chinensis and Physalis angulata were also active in vivo. [less ▲]

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See detailA la découverte de médicaments d'origine naturelle pour lutter contre le paludisme
Frederich, Michel ULg

Scientific conference (2009, October 08)

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See detailEvaluation des potentialités antiplasmodiales de plantes utilisées en médecine traditionnelle au Burkina Faso
Jansen, Olivia ULg; Nikiéma, Jean-Baptiste; Angenot, Luc ULg et al

Conference (2009, October 07)

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See detailAntisickling properties of divanilloylquinic acids isolated from Fagara zanthoxyloides Lam. (Rutaceae).
Ouattara, Badiore; Jansen, Olivia ULg; Angenot, Luc ULg et al

in Phytomedicine : International Journal of Phytotherapy and Phytopharmacology (2009), 16(2-3), 125-129

Fagara zanthoxyloides Lam. (syn. Zanthoxylum zanthoxyloides) (Rutaceae) is the most cited Fagara species for the treatment and the prevention of sickle cell disease crisis. Sickle cell anemia (SCA) is a ... [more ▼]

Fagara zanthoxyloides Lam. (syn. Zanthoxylum zanthoxyloides) (Rutaceae) is the most cited Fagara species for the treatment and the prevention of sickle cell disease crisis. Sickle cell anemia (SCA) is a public health problem in many countries particularly in Africa. The present study was designed to evaluate the antisickling properties of three isomeric divanilloylquinic acids (3,4-O-divanilloylquinic acid or burkinabin A; 3,5-O-divanilloylquinic acid or burkinabin B and 4,5-O-divanilloylquinic acid or burkinabin C) identified previously by LC/MS/NMR analysis in the root bark of F. zanthoxyloides [Ouattara et al., 2004. LC/MS/NMR analysis of isomeric divanilloylquinic acids from the root bark of Fagara zanthoxyloides Lam. Phytochemistry 65, 1145-1151]. The three isomers showed interesting antisickling properties which increased from burkinabins A to C. [less ▲]

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See detailMétabolomique - Identification de métabolites (biomarqueurs) par RMN 2D et LC-NMR
Frederich, Michel ULg

Conference (2009, January 28)

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See detailA la découverte de médicaments d'origine naturelle pour lutter contre le paludisme
Frederich, Michel ULg

Scientific conference (2009, January 27)

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See detailAntimalarial compounds isolated from plants used in traditional medicine.
Bero, Joanne; Frederich, Michel ULg; Quetin-Leclercq, Joelle

in Journal of Pharmacy & Pharmacology (2009), 61(11), 1401-33

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 ... [more ▼]

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 < or = 11 microm. 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. [less ▲]

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