References of "Quetin-Leclercq, Joëlle"
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See detailChemical composition, cytotoxicity and in vitro antitrypanosomal and antiplasmodial activity of the essential oils of four Cymbopogon species from Benin.
Kpoviessi, Salome; Bero, Joanne; Agbani, Pierre et al

in Journal of ethnopharmacology (2014), 151

ETHNOPHARMACOLOGICAL RELEVANCE: Cymbopogon species are largely used in folk medicine for the treatment of many diseases some of which related to parasitical diseases as fevers and headaches. As part of ... [more ▼]

ETHNOPHARMACOLOGICAL RELEVANCE: Cymbopogon species are largely used in folk medicine for the treatment of many diseases some of which related to parasitical diseases as fevers and headaches. As part of our research on antiparasitic essential oils from Beninese plants, we decided to evaluate the in vitro antiplasmodial and antitrypanosomal activities of essential oils of four Cymbopogon species used in traditional medicine as well as their cytotoxicity. MATERIALS AND METHODS: The essential oils of four Cymbopogon species Cymbopogon citratus (I), Cymbopogon giganteus (II), Cymbopogon nardus (III) and Cymbopogon schoenantus (IV) from Benin obtained by hydrodistillation were analysed by GC/MS and GC/FID and were tested in vitro against Trypanosoma brucei brucei and Plasmodium falciparum respectively for antitrypanosomal and antiplasmodial activities. Cytotoxicity was evaluated in vitro against Chinese Hamster Ovary (CHO) cells and the human non cancer fibroblast cell line (WI38) through MTT assay to evaluate the selectivity. RESULTS: All tested oils showed a strong antitrypanosomal activity with a good selectivity. Sample II was the most active against Trypanosoma brucei brucei and could be considered as a good candidate. It was less active against Plasmodium falciparum. Samples II, III and IV had low or no cytotoxicity, but the essential oil of Cymbopogon citraus (I), was toxic against CHO cells and moderately toxic against WI38 cells and needs further toxicological studies. Sample I (29 compounds) was characterised by the presence as main constituents of geranial, neral, beta-pinene and cis-geraniol; sample II (53 compounds) by the presence of trans-p-mentha-1(7),8-dien-2-ol, trans-carveol, trans-p-mentha-2,8-dienol, cis-p-mentha-2,8-dienol, cis-p-mentha-1(7),8-dien-2-ol, limonene, cis-carveol and cis-carvone; sample III (28 compounds) by beta-citronellal, nerol, beta-citronellol, elemol and limonene and sample IV (41 compounds) by piperitone, (+)-2-carene, limonene, elemol and beta-eudesmol. CONCLUSIONS: Our study shows that essential oils of Cymbopogon genus can be a good source of antitrypanosomal agents. This is the first report on the activity of these essential oils against Trypanosoma brucei brucei, Plasmodium falciparum and analysis of their cytotoxicity. [less ▲]

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See detailFast method for the simultaneous quantification of toxic polyphenols applied to the selection of genotypes of yam bean (Pachyrhizus sp.) seeds.
Lautié, Emmanuelle; Rozet, Eric ULg; Hubert, Philippe ULg et al

in Talanta (2013), 117

The purpose of the research was to develop and validate a rapid quantification method able to screen many samples of yam bean seeds to determine the content of two toxic polyphenols, namely pachyrrhizine ... [more ▼]

The purpose of the research was to develop and validate a rapid quantification method able to screen many samples of yam bean seeds to determine the content of two toxic polyphenols, namely pachyrrhizine and rotenone. The analytical procedure described is based on the use of an internal standard (dihydrorotenone) and is divided in three steps: microwave assisted extraction, purification by solid phase extraction and assay by ultra high performance liquid chromatography (UHPLC). Each step was included in the validation protocol and the accuracy profiles methodology was used to fully validate the method. The method was fully validated between 0.25mg and 5mg pachyrrhizin per gram of seeds and between 0.58mg/g and 4mg/g for rotenone. More than one hundred samples from different accessions, locations of growth and harvest dates were screened. Pachyrrhizine concentrations ranged from 3.29mg/g to lower than 0.25mg/g while rotenone concentrations ranged from 3.53mg/g to lower than 0.58mg/g. This screening along with principal component analysis (PCA) and discriminant analysis (DA) analyses allowed the selection of the more interesting genotypes in terms of low concentrations of these two toxic polyphenols. [less ▲]

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See detailAntiparasitic hybrids of Cinchona alkaloids and bile acids.
Leverrier, Aurelie; Bero, Joanne; Frederich, Michel ULg et al

in European journal of medicinal chemistry (2013), 66

A series of 16 hybrids of Cinchona alkaloids and bile acids (4a-h, 5a-h) was prepared by means of a Barton-Zard decarboxylation reaction. Quinine, quinidine, cinchonine and cinchonidine were ... [more ▼]

A series of 16 hybrids of Cinchona alkaloids and bile acids (4a-h, 5a-h) was prepared by means of a Barton-Zard decarboxylation reaction. Quinine, quinidine, cinchonine and cinchonidine were functionalized at position C-2 of the quinoline nucleus by radical attack of a norcholane substituent. The newly synthesized hybrids were evaluated in vitro for their antitrypanosomal, antileishmanial and antiplasmodial activities, along with their cytotoxicity against WI38, a normal human fibroblast cell line. Seven compounds (4d, 4f, 4h, 5b, 5d, 5f, 5h) showed promising trypanocidal activity with IC(5)(0) values in the same range as the commercial drug suramine. Moreover all the 16 hybrids showed antiplasmodial activity (IC(5)(0) </= 6 mug/ml), particularly those containing a nor-chenodeoxycholane moiety (4b, 4d, 4f, 4h, 5b, 5d, 5f, 5h) with IC(5)(0) values comparable to those of the natural alkaloids, and selectivity indices in the range of 5.6-15.7. [less ▲]

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See detailIn vivo antimalarial activity of Keetia leucantha twigs extracts and in vitro antiplasmodial effect of their constituents.
Bero, Joanne; Herent, Marie-France; Schmeda-Hirschmann, Guillermo et al

in Journal of Ethnopharmacology (2013), 149(1), 176-83

ETHNOPHARMACOLOGICAL RELEVANCE: The West African tree Keetia leucantha (Rubiaceae) is used in traditional medicine in Benin to treat malaria. The twigs dichloromethane extract was previously shown to ... [more ▼]

ETHNOPHARMACOLOGICAL RELEVANCE: The West African tree Keetia leucantha (Rubiaceae) is used in traditional medicine in Benin to treat malaria. The twigs dichloromethane extract was previously shown to inhibit in vitro Plasmodium falciparum growth with no cytotoxicity (>100microg/ml on human normal fibroblasts). MATERIALS AND METHODS: The dichloromethane and aqueous extracts of twigs of K. leucantha were evaluated in vivo against Plasmodium berghei NK 173 by the 4-day suppressive test and in vitro against a chloroquine-sensitive strain of Plasmodium falciparum (3D7) using the measurement of the plasmodial lactate dehydrogenase activity. Bioguided fractionations were realized and compounds were structurally elucidated using extensive spectroscopic analysis. RESULTS: The in vivo antimalarial activity of K. leucantha dichloromethane and aqueous twigs extracts were assessed in mice at the dose of 200mg/kg/day. Both extracts exhibited significant effect in inhibiting parasite growth by 56.8% and 53.0% (p<0.0001) on day 7-postinfection. An LC-MS analysis and bioguided fractionations on the twigs dichloromethane extract led to the isolation and structural determination of scopoletin (1), stigmasterol (2), three phenolic compounds: vanillin (3), hydroxybenzaldehyde (4) and ferulaldehyde (5), eight triterpenic esters (6-13), oleanolic acid and ursolic acid. The antiplasmodial activity of the mixture of the eight triterpenic esters showed an antiplasmodial activity of 1.66+/-0.54microg/ml on the 3D7 strain, and the same range of activity was observed for isolated isomers mixtures. CONCLUSIONS: This is the first report on the in vivo activity of K. leucantha extracts, the isolation of thirteen compounds and analysis of their antiplasmodial activity. The results obtained may partially justify the traditional use of K. leucantha to treat malaria in Benin. [less ▲]

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See detailIn vivo antimalarial activity of twigs extracts from Keetia leucantha
Béro, Joanne; Frederich, Michel ULg; Quetin-Leclercq, Joëlle

in Planta Medica (2012, August), 78(11), 1188

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See detailAntiparasitic activities of two sesquiterpenic lactones isolated from Acanthospermum hispidum D.C
Ganfon; Bero, Joanne; Tchinda Tiabou, Alembert ULg et al

in Journal of Ethnopharmacology (2012), 141(0), 411-417

Ethnopharmacological relevance : Aerial parts of Acanthospermum hispidum D.C. are often used by traditional healers in Benin for various diseases and especially for malaria Aim of the study : Identify ... [more ▼]

Ethnopharmacological relevance : Aerial parts of Acanthospermum hispidum D.C. are often used by traditional healers in Benin for various diseases and especially for malaria Aim of the study : Identify active compounds from extracts of Acanthospermum hispidum D.CV. leaves previously shown to possess antimalarial properties and analyse in vivo activity and toxicity of crude extracts. Materials and methods : Compounds were isolated from aerial part of A. hispidum D.C. and structurally elucidated using extensive spectroscopic analysis. Antiplasmodial activity was evaluated in vitro against a chloroquinosensitive strain of Plasmodium falciparum (3D7) using the measurement of the plasmodial lactate dehydrogenase activity and in vivo against P. berghei berghei by the 4-days suppressive test. Selectivity of extract and purified compounds on Plasmodium parasites were evaluated by using MTT test on J774 macrophage like murine cells and WI38 human normal fibroblasts and also against two other parasites: Trypanosoma brucei brucei and Leishmania mexicana mexicana. Acute and sub-acute toxicities of a crude extract were evaluated on mice. Results : Two known sesquiterpenic lactones were isolated: 1 (15-acetoxy-8β-[(2-methylbutyryloxy)]-14-oxo-4, 5-cis-acanthospermolide) and 2 (9α-acetoxy-15-hydroxy-8β-(2-methylbutyryloxy) -14-oxo-4, 5-trans-acanthospermolide). 1 and 2 showed in vitro antiplasmodial activity against the chloroquino-sensitive strain (3D7) with IC50 of 2.9 ± 0.5 and 2.23 ± 0.09 μM respectively. Only 2 showed a high selectivity index (SI: 18.4) on Plasmodium compared to cytotoxicity against human fibroblasts cell line (WI38). 1 and 2 also showed interesting antiparasitic activities in vitro against Trypanosoma brucei brucei (IC50 of 2.45 ± 0.49 and 6.36 ± 1.42 μM respectively) and Leishmania mexicana mexicana (IC50 of 0.94 ± 0.05 and 2.54 ± 0.19 μM respectively). Furthermore, crude acidic water extract and fractions containing one of the two isolated compounds displayed a weak in vivo antimalarial activity against P. berghei berghei with a long half-life causing a delayed effect. In vivo acute (2000 mg/kg) and sub-acute (1000 mg/kg) toxicity tests on the crude acidic water extract did not show toxicity. Conclusion : Crude acidic water extract, fractions and pure isolated compounds from A.hispidum showed promising in vitro antiplasmodial activity. Despite our study did not show in vivo acute and subacute toxicities of the crude acidic water extract, its weak in vivo antimalarial activity and the in vitro cytoxicity of pure compounds and enriched extracts containing 1 and 2 indicate that the aerial parts of A. hispidum should be used with caution for malaria treatments. [less ▲]

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See detailEspectroscopia aplicada
Ziemons, Eric ULg; Frederich, Michel ULg; Fillet, Marianne ULg et al

Scientific conference (2011, May)

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See detailApplication of experimental design for the HPLC-UV-MS separation of aporphine alkaloids from leaves of Spirospermum Penduliflorum thouars
Rafamantanana, Mamy H.; Debrus, Benjamin ULg; Raoelison, Guy E. et al

Poster (2010, September)

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See detailSimultaneous quantification os asiaticoside, asiatic acid, madecassoside and madecassic acid in leaves of Centella asiatica (L.) urb.
Rafamantanana, M. H.; Rozet, Eric ULg; Raoelison, G. E. et al

Poster (2010)

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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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See detailIn vitro antiplasmodial activity of plants used in Benin in traditional medicine to treat malaria
Bero, Joanne; Ganfon, Habib; Jonville, Marie ULg et al

in Journal of Ethnopharmacology (2009), 122

Aim of the study: The aim of the studywas to evaluate the in vitro antiplasmodial activity of crude extracts of 12 plant species traditionally used in Benin for the treatment of malaria in order to ... [more ▼]

Aim of the study: The aim of the studywas to evaluate the in vitro antiplasmodial activity of crude extracts of 12 plant species traditionally used in Benin for the treatment of malaria in order to validate their use. Materials and methods: For each species, dichloromethane, methanol and total aqueous extracts were tested. The antiplasmodial activity of extracts was evaluated using the measurement of the plasmodial lactate dehydrogenase activity on chloroquine-sensitive (3D7) and resistant (W2) strains of Plasmodium falciparum. The selectivity of the different extractswas evaluated using the MTT test on J774 macrophagelike murine cells and WI38 human normal fibroblasts. Results: The best growth inhibition of both strains of Plasmodium falciparum was observed with the dichloromethane extracts of Acanthospermum hispidum DC. (Asteraceae) (IC50 =7.5 g/ml on 3D7 and 4.8 g/ml on W2), Keetia leucantha (K. Krause) Bridson (syn. Plectronia leucantha Krause) (Rubiaceae) leaves and twigs (IC50 = 13.8 and 11.3 g/ml on 3D7 and IC50 = 26.5 and 15.8 g/ml on W2, respectively), Carpolobia lutea G.Don. (Polygalaceae) (IC50 = 19.4 g/ml on 3D7 and 8.1 g/ml on W2) and Strychnos spinosa Lam. (Loganiaceae) leaves (IC50 = 15.6 g/ml on 3D7 and 8.9 g/ml on W2). All these extracts had a low cytotoxicity. Conclusion: Our study gives some justifications for the traditional uses of some investigated plants. [less ▲]

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See detailPreliminary studies of development of oral pharmaceutical dosage forms contained extracts of Artemisia annua cultivated in Benin
Zime Diawara, Hermine; Gbaguidi, Fernand; Gbenou, Joachim et al

in Proceedings of 2nd PharmSci Fair (2009)

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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 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 detailValidation of a method for the determination of sterols and triterpenes in the aerial part of Justicia anselliana (Nees) T. Anders by capillary gas chromatography.
Kpoviessi, Dossou Sika Salome; Gbaguidi, Fernand; Gbenou, Joachim et al

in Journal of Pharmaceutical & Biomedical Analysis (2008), 48(4), 1127-35

An accurate and sensitive method, combining soxhlet extraction, solid phase-extraction and capillary gas chromatography is described for the quantitative determination of one triterpene (lupeol) and three ... [more ▼]

An accurate and sensitive method, combining soxhlet extraction, solid phase-extraction and capillary gas chromatography is described for the quantitative determination of one triterpene (lupeol) and three sterols (stigmasterol, campesterol and beta-sitosterol) and the detection of another triterpene (alpha-amyrin) from the aerial part of Justicia anselliana. This is the first method allowing the quantification of sterols and triterpenes in this plant. It has been fully validated in order to be able to compare the sterol and triterpene composition of different samples of J. anselliana and therefore help to explain the allelopathic activity due to these compounds. This method showed that the aerial part of J. anselliana contained (292+/-2)mg/kg of lupeol, (206+/-1)mg/kg of stigmasterol, (266+/-2)mg/kg of campesterol and (184+/-9)mg/kg of beta-sitosterol. [less ▲]

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See detailN1,N2,N3-trisisopentenyl guanidine and N1,N2-diisopentenyl guanidine, two cytotoxic alkaloids from Alchornea cordifolia (Schumach.& Thonn.) Mull. Arg. (Euphorbiaceae) root barks.
Mavar-Manga, H.; Chapon, David; Hoet, Sara et al

in Natural Product Communications [=NPC] (2006), 1(12), 1097-1100

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See detailInduction of Apoptosis in Human Promyelocytic Leukemia Cells by a Natural Trachylobane Diterpene
Block, Sébastien; Gerkens, Pascal; Peulen, Olivier ULg et al

in Anticancer Research (2005), 25(1A), 363-368

Background: Trachylobane diterpenes are secondary metabolites quite rare in nature and their bioactivities are poorly known. Recently we have described the cytotoxic activity of ent- trachyloban-3‚-ol ... [more ▼]

Background: Trachylobane diterpenes are secondary metabolites quite rare in nature and their bioactivities are poorly known. Recently we have described the cytotoxic activity of ent- trachyloban-3‚-ol isolated from the leaves of Croton zambesicus, a plant used in African folk medicine. Materials and Methods: Cell viability on several cell lines, cell morphology, DNA laddering, annexin V and caspase-3 activation experiments were undertaken in order to analyse the cytotoxicty of trachylobane diterpene and to determine if this compound is able to induce apoptosis. Results: ent-trachyloban-3‚-ol exerts a dose-dependent cytotoxic effect and which varies between cell lines. Induction of apoptosis in HL-60 cells could be detected at a concentration of 50 ÌM after 24-h treatment. Conclusion: We show here, for the first time, that a trachylobane diterpene is able to induce apoptosis in human promyelocytic leukemia cells via caspase-3 activation in a concentration-dependent manner. [less ▲]

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See detailDiterpenes from the leaves of Croton Zambesicus
Block, Sébastien; Baccelli, Chiara; Tinant, Bernard et al

in Phytochemistry (2004), 65

Two new trachylobane- and one isopimarane-type diterpenoids: ent-18-hydroxy-trachyloban-3-one; ent-trachyloban-3-one; isopimara-7,15-dien-3b-ol, were isolated from the leaves of Croton zambesicus ... [more ▼]

Two new trachylobane- and one isopimarane-type diterpenoids: ent-18-hydroxy-trachyloban-3-one; ent-trachyloban-3-one; isopimara-7,15-dien-3b-ol, were isolated from the leaves of Croton zambesicus, together with trans-phytol, b-sitosterol, a-amyrin and stigmasterol. The structures were determined by extensive NMR techniques and X-ray analysis. The cytotoxicity of these compounds has been evaluated on cancer and non-cancer cell-lines. [less ▲]

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