References of "Frederich, Michel"
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See detailAntioxidant Activity of Flavonoids Isolated From the Fruits of Xylopia parviflora (A. Rich.) Benth
Tchinda Tiabou, Alembert ULg; Agbor, GA; Tsala, DE et al

in International Journal of Pharmaceutical Sciences and Drug Research (2014), 6

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See detailPhytochemical analysis of Tetraclinis articula in relation to its vasorelaxant property.
zidane, Ahlam; Tits, Monique ULg; Angenot, Luc ULg et al

in Journal of Materials and Environmental Science (2014), 5(5), 1368-1375

Tetraclinis articulata (Cupressaceae), a traditional Moroccan herbal drug is used in oriental Morocco to treat diabetes and arterial hypertension. In a previous study we showed that the crude aqueous ... [more ▼]

Tetraclinis articulata (Cupressaceae), a traditional Moroccan herbal drug is used in oriental Morocco to treat diabetes and arterial hypertension. In a previous study we showed that the crude aqueous extract of T. articulata induces endotheliumdependent relaxation ... [less ▲]

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See detailAntioxidant Activity of Compounds Isolated from the Root Woods of Erythrina droogmansiana
Yaya, AJG; Feumba, RD; Emmanuel, T et al

in International Journal of Pharmaceutical Sciences and Drug Research (2014), 6(2), 160-163

The aim of this study was to isolate, to characterize secondary metabolites from methanolic extract of the root woods of Erythrina droogmansiana and to assess the antioxidant activity of the crude extract ... [more ▼]

The aim of this study was to isolate, to characterize secondary metabolites from methanolic extract of the root woods of Erythrina droogmansiana and to assess the antioxidant activity of the crude extract and isolated compounds. The phytochemical study led to the isolation of 3-(3’,4’-methelenedioxyphenyl)-2,3-epoxypropanol (1), asperphenamate (2) and three flavonoids namely genistein, diadzein and 4’,5,7-trihydroxy-8-prenylisoflavone. These compounds were characterized using their 1H NMR, 13C NMR, HMBC, HSQC, COSY, mass spectral and the literature. To evaluate antioxidant activity of crude extract and isolated compounds, the radical scavenging (DPPH) and Ferric Reducing Ability Power (FRAP) were performed using ascorbic acid as standard. Compounds 1 and 2 showed moderate radical scavenging potential with IC50 value of 3.14 and 3.31 mg/ml respectively, and moderate reducing power ability with value of 0.14±0.01 mgAAE/mg and 0.21±0.01 mgAAE/mg respectively. The more active compound was genistein (3) with IC50 value of 1.96 mg/ml for the DPPH radical scavenging potential and 0.24±0.02 mgAAE/mg for its ability to reduce iron. [less ▲]

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See detailIn Vitro and In Vivo Antiplasmodial Activity of Three Rwandan Medicinal Plants and Identification of Their Active Compounds
Muganga, Raymond; Angenot, Luc ULg; Tits, Monique ULg et al

in Planta Medica (2014), 80(6), 482-489

In our previous study, we reported the interesting in vitro antiplasmodial activity of some Rwandan plant extracts. This gave rise to the need for these extracts to also be evaluated in vivo and to ... [more ▼]

In our previous study, we reported the interesting in vitro antiplasmodial activity of some Rwandan plant extracts. This gave rise to the need for these extracts to also be evaluated in vivo and to identify the compounds responsible for their antiplasmodial activity. The aim of our study was, on the one hand, to evaluate the antiplasmodial activity in vivo and the safety of the selected Rwandan medicinal plants used in the treatment of malaria, with the objective of promoting the development of improved traditional medicines and, on the other hand, to identify the active ingredients in the plants. Plant extracts were selected according to their selectivity index. The in vivo antiplasmodial activity of aqueous, methanolic, and dichloromethane extracts was then evaluated using the classical 4-day suppressive test on Plasmodium berghei infected mice. The activity of the plant extracts was estimated by measuring the percentage of parasitemia reduction, and the survival of the experimental animals was recorded. A bioguided fractionation was performed for the most promising plants, in terms of antiplasmodial activity, in order to isolate active compounds identified by means of spectroscopic and spectrometric methods. The highest level of antiplasmodial activity was observed with the methanolic extract of Fuerstia africana (> 70 %) on days 4 and 7 post-treatment after intraperitoneal injection and on day 7 using oral administration. After oral administration, the level of parasitemia reduction observed on day 4 post-infection was 44 % and 37 % with the aqueous extract of Terminalia mollis and Zanthoxylum chalybeum, respectively. However, the Z. chalybeum extract presented a high level of toxicity after intraperitoneal injection, with no animals surviving on day 1 post-treatment. F. africana, on the other hand, was safer with 40 % mouse survival on day 20 post-treatment. Ferruginol is already known as the active ingredient in F. Africana, and ellagic acid (IC50 = 175 ng/mL) and nitidine (IC50 = 77.5 ng/mL) were identified as the main active constituents of T. mollis and Z. chalybeum, respectively. F. africana presented very promising antiplasmodial activity in vivo. Although most of the plants tested showed some level of antiplasmodial activity, some of these plants may be toxic. This study revealed for the first time the role of ellagic acid and nitidine as the main antimalarial compounds in T. mollis and Z. chalybeum, respectively. [less ▲]

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See detailStrychnobaillonine, an Unsymmetrical Bisindole Alkaloid with an Unprecedented Skeleton from Strychnos icaja Baill. Roots
Tchinda Tiabou, Alembert ULg; Jansen, Olivia ULg; Nyemb, Jean-Noel et al

in Journal of Natural Products (2014), 77

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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 detailPhysicochemical properties of lipids extracted from Tenebrio molitor larvae
Danthine, Sabine ULg; Blecker, Christophe ULg; Paul, Aman ULg et al

Poster (2013, December)

Objectives: To determine the physicochemical properties of the oil obtained from Tenebrio molitor Larvae and explore its potential as edible oil. Methodology: Oils obtained from five batches of Tenebrio ... [more ▼]

Objectives: To determine the physicochemical properties of the oil obtained from Tenebrio molitor Larvae and explore its potential as edible oil. Methodology: Oils obtained from five batches of Tenebrio molitor Larvae were investigated. Among the samples, three were produced directly in the lab (3 different productions) and 2 were purchased from a local supplier. In addition to the total lipid content (solvent extraction), both FA (GC) and TAG (HPLC) profiles were determined. Thermal properties by DSC were also estimated. Results and conclusion: The fresh Larvae from the lab contained 52% of total proteins (% dry matter). Their total fat content was around 36% (% dry matter). The commercial samples contained more proteins, but less fat: around 58% of total proteins and 30% of total fat (% dry matter). All the extracted oils contained high amount of unsaturated fatty acids. However, the chemical composition and the thermal properties of the samples varied according to their origin. The level and quality of lipid content offer potential as a substitute of oilseeds. [less ▲]

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See detailGrasshoppers: Food Security & Nutrition
Paul, Aman ULg; Danthine, Sabine ULg; Frederich, Michel ULg et al

Scientific conference (2013, December)

Rising economies and rapid urbanization in developing countries, particularly in Asia, are creating shifts in the composition of global food demand, so it is necessary to explore new sources of food with ... [more ▼]

Rising economies and rapid urbanization in developing countries, particularly in Asia, are creating shifts in the composition of global food demand, so it is necessary to explore new sources of food with better nutritional profile. Among the alternative food that exists are the grasshoppers, about 80 species of which are consumed worldwide. Grasshoppers are not only rich source of proteins and lipids but also some important minor component like vitamins and minerals. Apart from being nutritionally superior to most conventional meats their production results in lower emission of greenhouse gases & ammonia, risk of zoonotic infections in humans is much lower, water requirement for production is much less and have higher feed conversion ratio. Edible species of grasshopper in Belgium were identified, attempts were made for the lab rearing of meadow grasshopper (Chorthippus parallelus) and fat as well as protein contents of meadow grasshopper (Chorthippus parallelus) & long winged conehead (Conocephalus discolor) were investigated. [less ▲]

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See detailSome natural products from aerial parts of Scrophularia imerethica
Getia, M; Mshvildadze, V; Dekanosidze, G et al

Poster (2013, June 17)

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See detailLes substances naturelles dans la lutte contre le paludisme
Frederich, Michel ULg

Scientific conference (2013, May 25)

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See detailFalsification des médicaments: mythe ou réalité ?
Marini Djang'Eing'A, Roland ULg; Fillet, Marianne ULg; Vancauwenberghe, Roy et al

Conference (2013, April 24)

La santé publique est de nos jours minée par la problématique des médicaments falsifiés ou de qualité inférieure, avec plusieurs conséquences sanitaires, économiques voire professionnelles. On estime à 7 ... [more ▼]

La santé publique est de nos jours minée par la problématique des médicaments falsifiés ou de qualité inférieure, avec plusieurs conséquences sanitaires, économiques voire professionnelles. On estime à 7% la part du marché pharmaceutique mondial que représenterait ce fléau; l’Afrique, l’Asie et de nombreux pays d'Amérique latine étant les régions les plus touchées avec plus de 30% de médicaments falsifiés. D’après l'OMS, plus de 50% des médicaments achetés à partir des sites internet illégaux sont contrefaits, annihilant très fortement les chances de succès thérapeutique. Ces médicaments viennent dans la plupart des cas des pays asiatiques et de l’Eurasie. Le trafic de faux médicaments est un crime contre l'humanité qui représente environ 50 milliards de dollars par an (10-15 % de plus que le marché de la drogue). Au travers de deux leçons, la situation de la falsification des médicaments sera présentée au grand public dans le but de le sensibiliser à ce fléau. La première leçon présentera la situation en Europe avec un accent sur la Belgique. La problématique du droit à la propriété intellectuelle et de l’encadrement législatif sera abordée, ainsi que la falsification des médicaments modernes et des phytomédicaments, ces derniers étant utilisés par plus de 40% de la population en Europe et aux Etats-Unis. Dans la seconde leçon sera abordée la situation vécue en Afrique. L’approvisionnement en médicaments de qualité par le partage de l’information sera présenté ainsi que les moyens analytiques à la disposition de ce continent pour combattre ce fléau. Des membres du Département de Pharmacie de l’Université de Liège, de l’Agence Fédérale des Médicaments et des Produits de Santé ainsi que du programme QUAMED (Quality Medicines for All) feront partager leur expérience sur cette question d’une brûlante actualité.  [less ▲]

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See detailUnusual Amino Acids and Monofluoroacetate from Dichapetalum michelsonii (Umutambasha), a Toxic Plant from Rwanda
Esters, Virginie ULg; Karangwa, Charles; Tits, Monique ULg et al

in Planta Medica (2013), 79

In the course of our investigations on Umutambasha in order to identify its convulsant principles, small quantities of monofluoroacetate were observed in stem bark, leaves, and fruits of this plant newly ... [more ▼]

In the course of our investigations on Umutambasha in order to identify its convulsant principles, small quantities of monofluoroacetate were observed in stem bark, leaves, and fruits of this plant newly identified as Dichapetalum michelsonii Hauman. Conclusive evidence for a monofluoroacetate presence came from its isolation from the freeze-dried extract of stem bark. Three free unusual amino acids, named N-methyl-α-alanine, N-methyl-β-alanine, and 2,7-diaminooctan-1,8-dioic acid, described for the first time in a plant, and known trigonelline were also isolated from the stem bark of D. michelsonii. Structure elucidations were mainly achieved by spectroscopic methods (1H-NMR, 2D-NMR, MS) and by comparison with authentic references. These unusual amino acids were detected by a fast, reliable TLC analysis in all our batches of Umutambasha, suggesting that they could be used for identification purposes in case of human or livestock intoxications. Finally, EEG recordings and behavioural observations performed in mice suggested that the convulsive patterns produced by Umutambasha are the consequence of monofluoroacetate presence in D. michelsonii. [less ▲]

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See detailIdentification and structure elucidation of four cannabimimetic compounds in seized products
Denooz, Raphaël ULg; VAN HEUGEN, Jean-Claude ULg; Frederich, Michel ULg et al

in Journal of Analytical Toxicology (2013), 37(2), 56-63

Since 2008, herbal mixtures with synthetic cannabinoid compounds have been sold as incense throughout the world. Although these new drugs are labeled as not for human consumption, these products are ... [more ▼]

Since 2008, herbal mixtures with synthetic cannabinoid compounds have been sold as incense throughout the world. Although these new drugs are labeled as not for human consumption, these products are smoked for their cannabis-like effects. This study reports the structural and spectral elucidation of four cannabimimetic compounds seized in Belgium: (4-methoxyphenyl)-1-(pentyl-1H-indol-3-yl)methanone (RCS-4), 1-(5-fluoropentyl)-3-(1-naphtoyl)indole (AM-2201), 2-(2-chlorophenyl)-1-(1-pentylindol-3-yl)ethanone (JWH-203) and 4-ethylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone (JWH-210). Laboratory investigations were conducted by liquid chromatography (LC)–ultraviolet spectroscopy, high-resolution accurate mass detection and nuclear magnetic resonance (NMR) analysis. This combined analytical approach allowed the detection of illicit compounds for which reference materials were not available. To facilitate identification and to complete existing databases, ultraviolet spectra and NMR data of all seized products are presented. Additionally, LC–quadrupole time-of-flight data were recorded to provide absolute identification. [less ▲]

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See detailIsolation, pharmacological activity and structure determination of physalin B and 5[beta],6[beta]-ep­oxy­physalin B isolated from Congolese Physalis angulata L.
Mangwala Kimpende, P.; Lusakibanza, M.; Mesia, K. et al

in Acta Crystallographica Section C-Crystal Structure Communications (2013), C69

Physalis angulata L., an annual herb from the Solanaceae family, is widely used in popular medicine in tropical countries to treat a variety of diseases. Two products, (X) and (Y), were isolated from a ... [more ▼]

Physalis angulata L., an annual herb from the Solanaceae family, is widely used in popular medicine in tropical countries to treat a variety of diseases. Two products, (X) and (Y), were isolated from a crude CH2Cl2 extract of dried Congolese Physalis angulata L. plants and crystallized from acetone for structure elucidation. Compound (X) corresponds to a physalin B dimer acetone solvate hydrate (2C28H30O9·C3H6O·0.22H2O), while compound (Y) crystallizes as a mixed crystal containing two physalin B mol­ecules which overlap with 5[beta],6[beta]-ep­oxy­physalin B, also known as physalin F, and one acetone mol­ecule in the asymmetric unit (1.332C28H30O9·0.668C28H30O10·C3H6O). Anti­­plasmodial activity, cytotoxic activity and selectivity indices were determined for crude extracts and the two isolated products (X) and (Y). [less ▲]

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See detailPhenolic acid-rich extract of sweet basil restores cholesterol and triglycerides metabolism in high fat diet-fed mice: A comparison with fenofibrate
Harnafi, H.; Ramchoun, M.; Tits, Monique ULg et al

in Biomedicine & Preventive Nutrition (2013), 3(4), 393-397

Many spices are often added to foods as additives to enhance organoleptic qualities, such as flavor, aroma and color. Sweet basil (Ocimum basilicum L.) family of Lamiaceae is widely used in cooking for ... [more ▼]

Many spices are often added to foods as additives to enhance organoleptic qualities, such as flavor, aroma and color. Sweet basil (Ocimum basilicum L.) family of Lamiaceae is widely used in cooking for its culinary attributes. In this study, we aimed at the investigation of the hypocholesterolemic and hypotriglyceridemic activities of the basil phenolic acid-rich extract in high fat diet-induced hyperlipemic mice. Hyperlipemia was developed by a high fat diet containing cholesterol, lard and cholic acid. At the beginning of the experiment, animals were divided into three groups, one of them served as normolipidemic control group (NCG), the second hyperlipidemic control group (HCG) and the third basil-treated group (BTG). After 5 weeks of treatment, basil phenolic acid-rich extract significantly decreased plasma total cholesterol, triglycerides and LDL-cholesterol (-42%,-42% and -86%, respectively, P < 0.001). However, HDL-cholesterol was increased (+79%, P < 0.001). The extract reduced the atherogenic index and LDL/HDL-C ratio (-88% and -94%, respectively, P < 0.001). The reductions of liver total cholesterol and triglycerides were of -50% (P < 0.01) and -58% (P < 0.01), respectively. The hypolipemic effect of the phenolic acid-rich extract is comparable to that exerted by fenofibrate. This drug significantly reduced plasma total cholesterol, triglycerides and LDL-cholesterol (-25.5%, -51%, and -83.5%, respectively, P < 0.001) and increased plasma HDL-cholesterol (+136%, P < 0.001). On the other hand, fenofibrate significantly decreased atherogenic index and LDL/HDL-cholesterol ratio (-91% and -93%, respectively, P < 0.001). The fenofibrate decreased hepatic total cholesterol by 59.5% and triglycerides by 72%, respectively (P < 0.01). HPLC analysis led to identify four major compounds: caftaric acid, cafeic acid, chicoric acid and rosmarinic acid. In conclusion, the Sweet basil contains phenolic products that are able to lower hyperlipidemia and prevent atherosclerosis. © 2013 Elsevier Masson SAS. All rights reserved. [less ▲]

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See detailIdentification and Quantification of the Main Active Anticancer Alkaloids from the Root of Glaucium flavum
bournine, Lamine; Bensalem, Sihem; Wauters, Jean-Noël ULg et al

in International Journal of Molecular Sciences (2013), 14

Glaucium flavum is used in Algerian folk medicine to remove warts (benign tumors). Its local appellations are Cheqiq el-asfar and Qarn el-djedyane. We have recently reported the anti-tumoral activity of ... [more ▼]

Glaucium flavum is used in Algerian folk medicine to remove warts (benign tumors). Its local appellations are Cheqiq el-asfar and Qarn el-djedyane. We have recently reported the anti-tumoral activity of Glaucium flavum root alkaloid extract against human cancer cells, in vitro and in vivo. The principal identified alkaloid in the extract was protopine. This study aims to determine which component(s) of Glaucium flavum root extract might possess potent antitumor activity on human cancer cells. Quantitative estimation of Glaucium flavum alkaloids was realized by HPLC-DAD. Glaucium flavum effect on human normal and cancer cell viability was determined using WST-1 assay. Quantification of alkaloids in Glaucium flavum revealed that the dried root part contained 0.84% of protopine and 0.07% of bocconoline (w/w), while the dried aerial part contained only 0.08% of protopine, glaucine as the main alkaloid, and no bocconoline. In vitro evaluation of the growth inhibitory activity on breast cancer and normal cells demonstrated that purified protopine did not reproduce the full cytotoxic activity of the alkaloid root extract on cancer cell lines. On the other hand, bocconoline inhibited strongly the viability of cancer cells with an IC50 of 7.8 µM and only a low cytotoxic effect was observed against normal human cells. Our results showed for the first time that protopine is the major root alkaloid of Glaucium flavum. Finally, we are the first to demonstrate a specific anticancer effect of Glaucium flavum root extract against breast cancer cells, which can be attributed, at least in part, to bocconoline. [less ▲]

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See detailApplication de la résonance magnétique nucléaire (RMN) en toxicologie judiciaire
Denooz, Raphaël ULg; Frederich, Michel ULg; Charlier, Corinne ULg et al

in Acta Clinica Belgica (2013), 68(6), 470

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See detailIdentification and determination of alkaloids in Fumaria Species from Romania
Paltinean, Ramona; Toju, A; Wauters, Jean-Noël ULg et al

in Digest Journal of Nanomaterials & Biostructures [=DJNB] (2013), 8(2), 817-824

Four Fumaria species (F. vaillantii Loisel, F. parviflora Lam., F. rostellata Knaf and F. jankae Hausskn.) were analysed in order to determine the presence of the isoquinoline alkaloids allocryptopine ... [more ▼]

Four Fumaria species (F. vaillantii Loisel, F. parviflora Lam., F. rostellata Knaf and F. jankae Hausskn.) were analysed in order to determine the presence of the isoquinoline alkaloids allocryptopine, chelidonine, protopine, bicuculline, sanguinarine, cheleritrine, stylopine, and hydrastine through an HPLC-DAD method. Protopine and sanguinarine were present in all extracts. Bicuculline and stylopine were found in F. vaillantii and F. parviflora, whilst chelidonine was identified only in F. vaillantii and hydrastine in F. jankae, so they represent potential taxonomic markers that differentiate the four plants. The richest species in isoquinoline alkaloids was F. parviflora. Our study showed significant differences between the four Fumaria species, both qualitative and quantitative. [less ▲]

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