Search

Ethnopharmacological Relevance: Syzygium guineense has been traditionally used in Mali in West Africa for the treatment of different diseases such as stomach problems, wounds, inflammations and various female disorders., Aims of the Study: (1) To perform an ethnopharmacological survey on the traditional use of S. guineense among Malian healers. (2) To isolate and identify chemical constituents from S. guineense leaves and to study their radical scavenging and enzyme inhibitory effects., Materials and Methods: In four different districts in Mali, 44 healers were interviewed about their medicinal use of S. guineense. A methanol extract of the leaves of this tree was prepared and further fractionated using different chromatographic methods. Isolated compounds were identified by 1D and 2D NMR spectroscopy. Extracts and isolated compounds were investigated as DPPH radical scavengers and as inhibitors of xanthine oxidase and 15-lipoxygenase, and the methanol extract was tested for toxicity towards Artemia salina nauplii., Results: Major uses by Malian healers were against dermatosis, pain, malaria/fever and for wound healing. There was little consensus about the use in the different districts. Leaves were most commonly used. From the methanol leaf extract, the flavonoids gallocatechin (1), myricetin (2), myricetin-3-O-glucoside (3), myricetin-3-O-rhamnoside (4), myricetin-3-O-glucuronide (5) and myricetin-3-O-β-D-(6″-galloyl)galactoside (6), the gallotannins 1,2,3,6-tetra-O-galloyl-β-D-glucose (7) and 1,2,3,4,6-penta-O-galloyl-β-D-glucose (8), and the ellagitannins casuarictin (9) and casuarinin (10) were isolated. These ten polyphenols are all new for the species. The crude methanol extract was active as a radical scavenger and as an inhibitor of xanthine oxidase and 15-lipoxygenase. Among the isolated compounds, pentagalloylglucose was the best enzyme inhibitor (IC 50 25±4μM for 15-lipoxygenase, 8±1μM for xanthine oxidase), while casuarictin (IC 50 3.9±0.1μM), casuarinin (IC 50 4.5±0.3μM) and pentagalloylglucose (IC 50 5±1μM) showed the highest radical scavenging activity. The methanol extract was non-toxic to Artemia salina nauplii., Conclusion: S. guineense leaves are commonly used among Malian healers, however the traditional practice varies a lot between different regions. The leaves of S. guineense are rich in polyphenols; several are galloylated, either as galloylated flavonoids, gallotannins or ellagitannins. The high content of biologically active polyphenols might be important for medicinal effects of this plant and might give a rationale for the widespread usage of S. guineense in Mali., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Biophytum umbraculum Welw. (Oxalidaceae) is a highly valued African medicinal plant used for treatment of cerebral malaria, a critical complication of falciparum malaria., Aim of the Study: To provide additional information about traditional use of B. umbraculum and to test plant extracts and isolated compounds for in vitro activities related to cerebral malaria., Materials and Methods: The traditional practitioners were questioned about indication, mode of processing/application, dosage and local name of B. umbraculum. Organic extracts and some main constituents of the plant were investigated for anti-malaria, anti-complement activity and inhibition of NO secretion in a RAW 264.7 cell line., Results: Treatment of cerebral malaria was the main use of B. umbraculum (fidelity level 56%). The ethyl acetate extract showed anti-complement activity (ICH50 5.7±1.6μg/ml), inhibition of macrophage activation (IC50 16.4±1.3μg/ml) and in vitro antiplasmodial activity (IC50 K1 5.6±0.13μg/ml, IC50 NF54 6.7±0.03μg/ml). The main constituents (flavone C-glycosides) did not contribute to the activity of the extract., Conclusion: Inhibition of complement activation and anti-inflammatory activity of B. umbraculum observed in this study might be possible targets for adjunctive therapy in cerebral malaria together with its antiplasmodial activity. However, clinical trials are necessary to evaluate the activity due to the complex pathogenesis of cerebral malaria., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Protection of intellectual property rights and benefit-sharing are key issues for all ethnopharmacological research. The International Society of Ethnobiology has produced helpful guidelines on access and benefit-sharing which are widely viewed as a "gold standard" but the question remains how best to apply these guidelines in practice. Difficult questions include ownership of traditional knowledge, making appropriate agreements, and how appropriately to share benefits., Materials and Methods: We present the case study of the development of an "improved traditional medicine" for malaria in Mali and we report how benefit-sharing was applied in this case., Results: The knowledge about the selected plant came independently from several families and traditional healers. The IPR approach was to recognise that this traditional knowledge belongs to the people of Mali and was used for their benefit in developing a new "improved traditional medicine" (ITM). The traditional healer whose method of preparation was used, and who collaborated in clinical trials, did not request any financial reward but asked for the ITM to be named after him. The most sustainable benefit for the community was sharing the results of which preparation of which medicinal plant seemed to be the most effective for treating malaria. Attempts at providing a health centre and training a health worker for the village did not prove to be sustainable., Conclusions: Respect for intellectual property rights and benefit-sharing are possible even in a context where the knowledge is not owned by a clearly identified person or group of people. The most sustainable benefits are intangible rather than material: namely recognition, improved knowledge about which traditional treatment is the best and how to prepare and take it., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Mali is one of the countries in West Africa where the health system rely the most on traditional medicine. The healers are mainly using medicinal plants for their treatments. The studies performed being the basis for this review is of importance as they will contribute to sustaining the traditional knowledge. They contribute to evaluate and improve locally produced herbal remedies, and the review gives also an overview of the plant preparations that will have the most potential to be evaluated for new Improved Traditional Medicines., Aim of the Review: The aim of this review is to give an overview of the studies performed related to medicinal plants from Mali in the period 1995-2015. These studies include ethnopharmacology, chemistry and biological studies of the plants that were chosen based on our interviews with the healers in different regions of Mali, and contribute to sustainable knowledge on the medicinal plants. The Department of Traditional Medicine, Bamako, Mali, is responsible for registering the knowledge of the traditional healers on their use of medicinal plants and also identifying compounds in the plants responsible for the bioactivities claimed. The studies reported aimed at getting information from the healers on the use of medicinal plants, and study the biology and chemistry of selected plants for the purpose of verifying the traditional use of the plants. These studies should form the basis for necessary knowledge for the development of registered Improved Traditional Medicines in Mali., Materials and Methods: The healers were the ethnopharmacological informants. Questions asked initially were related to wound healing. This was because the immune system is involved when wounds are healed, and additionally the immune system is involved in the majority of the illnesses common in Mali. Based on the results of the interviews the plant material for studies was selected. Studies were performed on the plant parts the healers were using when treating their patients. Conventional chromatographic and spectroscopic methods were used for the isolation and structural elucidation of compounds. The compounds to study were selected based on the bioassays performed concomitant with the fractionation., Results: Our results show that plants traditionally used as wound healing agents contain polysaccharides basically of pectin nature with immunomodulating activities. These pectins all have different and new structures. Several of the plants also contain compounds with effects related to antioxidant properties. These compounds are mainly of polyphenolic nature. Three of these are new compounds from Nature, while 32 was for the first time described from the plant they were isolated from. This review gives an overview of the most important results obtained during the 20 year long collaboration between Department of Traditional Medicine, Bamako, Mali, and Department of Pharmacognosy, School of Pharmacy, University of Oslo, Norway., Conclusion: Our studies showed that ethnopharmacological information is important for the determination of screening and chemical methods to be used for studies of plants used in traditional medicine., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Plants have contributed to food security and disease treatments to rural populations in sub Saharan Africa for many centuries. These plants occupy a significant place in the treatment of diseases, such as malaria. In Mali, malaria is the leading cause of medical consultation and death. This infection is particularly dangerous for pregnant women and children under 5 years. The general aim of this research was to collect data on the knowledge of traditional health practitioners on malaria in the Sélingué area; particularly to document how traditional healers conceptualize and diagnose malarial disease and to collect and identify medicinal plants or other substances used for their health and well-being., Materials and Methods: An ethnobotanical survey was conducted on simple and complicated malaria in six villages in Sélingué subdistrict in a period of 2 months. The ethnobotanical data was collected by means of semi-structured interviews and questionnaires. In total 50 traditional healers were interviewed., Results: Two concepts of malaria (simple and complicated malaria) were cited and 97 plants used to treat malaria were identified. Decoctions and bathing (whole body) proved to be the most commonly used mode of application. Food attitudes and mosquitoes are perceived to be the most important causes of the disease. Trichilia emetica, Mitragyna inermis, Sarcocephalus latifolius, Cassia sieberiana, Cochlospermum tinctorium, Anogeissus leiocarpa, Guiera senegalensis and Entada africana were quoted as the most used in the treatment of malaria., Conclusion: Knowledge about malaria and traditional treatment practices exist in Sélingué subdistrict. Herbal remedies are commonly used by people for the treatment of malaria because they are believed to be cost-effective and more accessible. Many of the plant species used for the treatment of malaria have not been well documented as well as their phytochemical and antimalarial activity., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Snakebite envenomation causes 5000-10,000 mortalities and results in more than 5-15,000 amputations in sub-Saharan Africa alone every year. The inaccessibility of antiserum therapy is a vast problem, and only about 2.5% of the actual need for antiserum in Africa is covered. Numerous plants have shown in vitro inhibitory activity against one or more of the hydrolytic enzymes involved in snakebite-induced necrosis. However, a more thorough examination of the plant species in ex vivo and in vitro cell assay models is needed to test their ability to inhibit necrosis., Materials and Methods: Extracts which had previously shown in vitro inhibitory activity against necrosis enzymes, were tested in an ex vivo air-liquid-interface model, and a wound healing scratch assay as well as for their ability to permeate the skin barrier and inhibit venom induced cell death., Results: Of the 14 water extracts and 16 ethanol extracts tested at a concentration of 10 μg/mL, only the ethanol extracts of Tamarindus indica and Paullinia pinnata resulted in a small but significant increase in cell migration of around 10% compared to treatment with buffer after 24h treatment. The remaining extracts showed no effect, or they even delayed the cell migration compared to the treatment with buffer. After 48 h treatment, 10 of the tested extracts showed a decreased cell migration compared to no treatment. At a 100 μg/mL concentration all the extracts inhibited cell migration and five extracts killed some of the cells, while four extracts killed all the cells. Ten of the thirty extracts were tested in a Franz cell set-up but none of the extracts tested did permeate the skin barrier over a 48 h period, and will therefore be of very limited use topically in the initial treatment of snakebites in its present form. None of the extracts were able to directly interact with the enzyme to lower the cell toxicity of the venom. Two extracts, Dichrostachys cinerea and Grewia mollis, were tested in the ex vivo model, but none of them inhibited the tissue destruction caused by venom., Conclusion: On the basis of this study, topical treatment with plant extracts for snakebite-induced tissue necrosis cannot be recommended., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Snakebite envenomation, every year, causes estimated 5-10,000 mortalities and results in more than 5-15,000 amputations in sub-Saharan Africa alone. Antiserum is not easily accessible in these regions or doctors are simply not available, thus more than 80% of all patients seek traditional practitioners as first-choice. Therefore it is important to investigate whether the plants used in traditional medicine systems contain compounds against the necrosis-inducing enzymes of snake venom., Materials and Methods: Extracts from traditionally used plants from DR Congo, Mali and South Africa were tested in hyaluronidase, phospholipase A2 and protease enzyme bioassays using Bitis arietans and Naja nigricollis as enzyme source., Results: A total of 226 extracts from 94 different plant species from the three countries, Mali, Democratic Republic of Congo and South Africa were tested in phospholipase A2, proteases and hyaluronidase enzyme assays. Forty plant species showed more than 90% inhibition in one or more assay. Fabaceae, Anacardiaceae and Malvaceae were the families with the highest number of active species, and the active compounds were distributed in different plant parts depending on plant species. Polyphenols were removed in the search for specific enzyme inhibitors against hyaluronidase, phospholipase A2 or proteases from extracts with IC50 values below 100µg/ml. Water extracts of Pupalia lappacea, Combretum molle, Strychnos innocua and Grewia mollis and ethanol extract of Lannea acida and Bauhinia thonningii still showed IC50 values below 100µg/ml in either the hyaluronidase or protease bioassay after removal of polyphenols., Conclusion: As four of the active plants are widely distributed in the areas where the snake species Bitis arietans and Naja nigricollis occur a potential inhibitor of the necrotic enzymes is accessible for many people in sub-Saharan Africa., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: The root bark, stem bark and leaves of Terminalia macroptera have been traditionally used against a variety of ailments such as wounds, hepatitis, malaria, fever, cough, and diarrhea as well as tuberculosis and skin diseases in African folk medicine. Boiling water extracts of Terminalia macroptera, administered orally, are the most common preparations of this plant used by the traditional healers in Mali. This study aimed to investigate the inhibition of the activities of α-glucosidase, 15-lipoxygenase and xanthine oxidase, DPPH scavenging activity, complement fixation activity and brine shrimp toxicity of different extracts obtained by boiling water extraction (BWE) and by ASE (accelerated solvent extraction) with ethanol, ethanol-water and water as extractants from different plant parts of Terminalia macroptera., Materials and Methods: 27 different crude extracts were obtained by BWE and ASE from root bark, stem bark and leaves of Terminalia macroptera. The total phenolic and carbohydrate contents, enzyme inhibition activities (α-glucosidase, 15-lipoxygenase and xanthine oxidase), DPPH scavenging activity, complement fixation activity and brine shrimp toxicity of these extracts were evaluated. Principal component analysis (PCA) was applied for total biological activities evaluation., Results: Several of the extracts from root bark, stem bark and leaves of Terminalia macroptera obtained by BWE and ASE showed potent enzyme inhibition activities, radical-scavenging properties and complement fixation activities. None of the extracts are toxic against brine shrimp larvae in the test concentration. Based on the results from PCA, the ASE ethanol extracts of root bark and stem bark and the low molecular weight fraction of the 50% ethanol-water extract of leaves showed the highest total biological activities. The boiling water extracts were less active, but the bark extracts showed activity as α-glucosidase inhibitors and radical scavengers, the leaf extract being less active., Conclusion: The observed enzyme inhibition activities, radical scavenging properties and complement fixation activities may explain some of the traditional uses of this medicinal tree, such as in wound healing and against diabetes., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Water decoctions of the root bark, stem bark and leaves of Terminalia macroptera are used by traditional healers in Mali to cure a wide range of illnesses, such as wounds, hepatitis, malaria, fever, cough and diarrhea as well as tuberculosis. Plant polysaccharides isolated from crude water extracts have previously shown effects related to the immune system. The aims of this study are comparing the properties of the polysaccharides among different plant parts, as well as relationship between chemical characteristics and complement fixation activities when the plant material has been extracted as the traditional healers do, with boiling water directly., Materials and Methods: Root bark, stem bark and leaves of Terminalia macroptera were extracted by boiling water, and five purified polysaccharide fractions were obtained by anion exchange chromatography and gel filtration. Chemical compositions were determined by GC of the TMS derivatives of the methyl-glycosides and the linkage determined after permethylation and GC-MS of the derived partly methylated alditol acetates. The bioactivity was determined by the complement fixation assay of the crude extracts and purified fractions., Results: The acidic fraction TRBD-I-I isolated from the root bark was the most active of the fractions isolated. Structural studies showed that all purified fractions are of pectic nature, containing rhamnogalacturonan type I backbone. Arabinogalactan type II side chains were present in all fractions except TRBD-I-II. The observed differences in complement fixation activities among the five purified polysaccharide fractions are probably due to differences in monosaccharide compositions, linkage types and molecular sizes., Conclusion: The crude extracts from root bark and stem bark have similar total activities, both higher than those from leaves. The root bark, leaves and stem bark are all good sources for fractions containing bioactive polysaccharides. But due to sustainability, it is prefer to use leaves rather than the other two plant parts, and then the dosage by weight must be higher when using leaves., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Roots from Vernonia kotschyana are on the national list of essential drugs in Mali (West-Africa). It is sold under the name Gastrosedal and it used against ailments like gastritis and gastric ulcer. To evaluate the anti-ulcer, immunomodulating activities and toxicity of 50 and 100 °C water extracts, Vk50-I and Vk100-I respectively, from the roots of Vernonia kotschyana., Materials and Methods: Characterization of extracts was carried out by GC, colorimetric and biological methods. Vk50-I and Vk100-I were administrated 50 min before induction of gastric ulcers in mice with 0.3 M HCl-60% EtOH. Inhibition of ulcer formation was calculated based on lesion index. Immunological activities were measured by complement fixation and macrophage activation. Toxicity assay was carried out on brine shrimps., Results: Vk50-I (98% inulin) and Vk100-I (83% inulin) from Vernonia kotschyana significantly inhibited the formation of gastric lesions in mice (100 mg/kg). No immunomodulating activities or toxicity were found., Conclusions: Our results show that inulin is probably partly responsible for the anti-ulcer activity of Gastrosedal. In addition, it is possible that water soluble polysaccharides (mainly inulin) have an indirect impact on the general health of the GI., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Aqueous extracts of bark and leaves of C. cordifolia are traditionally used in Mali (West Africa) in the treatment of wounds and gastric ailments like abdominal pain, gastritis and gastric ulcers., Aim of the Study: To evaluate and compare the anti-ulcer and immunological activities, as well as the toxicity of polysaccharide rich water extracts from the bark and leaves of C. cordifolia., Materials and Methods: Gastric ulcers were induced in rats and the inhibition of ulcer formation was calculated based on lesion index. Immunological activities were measured by complement fixation and macrophage activation. Toxicity was tested on brine shrimps. The two extracts were characterised by GC, Yariv-precipitation and quantification of phenolic compounds. An ethnomedical survey on C. cordifolia was carried out in Siby (Mali, West-Africa) to generate more knowledge about the traditional use., Results: Bark and leaf extracts from C. cordifolia significantly inhibited the formation of gastric lesions in rodents in a dose depending manner. CCbark50 showed a high complement fixation activity in vitro. No toxicity was found. The ethnomedical survey showed that C. cordifolia was mainly used for treating pain and wounds., Conclusions: Our results shows that the bark and the leaves comprise a dose dependant anti-ulcer activity in an experimental rat model (no statistical difference between the plant parts). Clinical studies should be performed to evaluate the effect of both bark and leaves of C. cordifolia as a remedy against gastric ulcer in human., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Ximenia americana is a medicinal bushy, spiny shrub or small tree used in Mali in West Africa for treatment of various diseases, most common are infectious and inflammatory ailments., Aims of the Study: (1) To perform an ethnopharmacological survey on the traditional use of Ximenia americana among healers in Mali. (2) To isolate and identify chemical constituents from the ethanol extract of Ximenia americana leaves and to study their radical scavenging and enzyme inhibitory effects., Materials and Methods: In five different districts in Mali, 38 healers were interviewed about their medicinal use of Ximenia americana. An aqueous ethanol extract of the leaves of this tree was prepared and further fractionated with liquid-liquid extraction, VersaFlash and Sephadex LH-20 column chromatography, and preparative HPLC. Isolated compounds were identified by 1D and 2D NMR spectroscopy. Extracts, subfractions and isolated compounds were investigated as DPPH radical scavengers and as inhibitors of xanthine oxidase and 15-lipoxygenase., Results: Major areas of use by Malian healers were against throat infection, amenorrhea and as tonic. Fractionation of the ethanol extract led to the isolation and identification of the cyanogenic glycoside sambunigrin (1), which is previously known from the plant. Additionally, gallic acid (2) and the gallotannins β-glucogalline (3) and 1,6-digalloyl-β-glucopyranose (4) were found. The following flavonoids were isolated: quercetin (5), quercitrin (quercetin-3-O-α-rhamnopyranoside) (6), avicularin (quercetin-3-O-α-arabinofuranoside) (7), quercetin-3-O-β-xylopyranoside (8), quercetin-3-O-(6″-galloyl)-β-glucopyranoside (9) and kaempferol-3-O-(6″-galloyl)-β-glucopyranoside (10). The flavonoids were active both as enzyme inhibitors and DPPH radical scavengers., Conclusion: Sambunigrin (1) was the main compound in the EtOAc soluble fraction of the alcoholic extract of Ximenia americana leaves. Gallic acid (2), gallotannins (3-4) and flavonoids (5-10) were identified for the first time in the genus Ximenia. The identified compounds may give a rationale for the traditional use of Ximenia americana in Mali. Healers interviewed reported the use against throat infections, amenorrhea, as tonic, for wound healing and against pain., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: In Malian traditional medicine the roots of Vernonia kotschyana are used for treating gastric ulcer and gastritis. In 2006, 9000kg of roots from Vernonia kotschyana were used to produce Gastrosedal, an ameliorated traditional medicine in Mali. Harvesting from the wild, the main source of raw material, is causing a growing concern of diminishing populations of the plant, and Vernonia kotschyana is now being cultivated in several areas around Mali. In the current study the structures and bioactive properties of isolated polysaccharides from wild and cultivated Vernonia kotschyana were compared., Materials and Methods: Pectin- and inulin-type polysaccharides were isolated from the roots of cultivated and wild Vernonia kotschyana. The isolated polysaccharides were investigated regarding their chemical compositions, and for their abilities to fixate human complement and activate macrophages from a mouse macrophage cell line., Results: No significant differences in the carbohydrate composition of the fractions isolated from the cultivated versus the wild roots were observed. A previously reported pectic arabinogalactan Vk2a was found in both the cultivated and the wild roots in this study, and exhibited potent complement fixation activity, and a moderate activation of macrophages., Conclusions: The present study has shown that the cultivated roots of Vernonia kotschyana contain the same types of bioactive polysaccharides as the wild roots. It is therefore preliminarily feasible for the cultivated roots of Vernonia kotschyana to be used as a herbal medicine to replace the wild roots., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

The tree Terminalia macroptera (Combretaceae) is widespread in Western Africa, and in this area, different parts have been utilized in the treatment of various diseases. In this article, we report on the medicinal use of T. macroptera in three different districts in Mali (Siby, Dioïla and Dogonland), based on interviews with 78 healers in these districts. Roots, root bark, stem bark, leaves and fruits have all been employed by healers, as has parasitic Loranthus species growing on the tree. Major areas of use comprise treatment of wounds and sores, infections, pain, cough, tuberculosis and hepatitis. Some of the medicinal uses of T. macroptera appear to be rationally explained by its chemical constituents., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Several medicinal plants are used in Mali to treat epilepsy and convulsions. So far, no studies have investigated the pharmacological effect of these plants., Aims: The aim of this study was to investigate the in vitro and in vivo antiepileptic potential of the ethanolic extracts of 11 Malian medicinal plants., Materials and Methods: The extracts were screened for antiepileptic properties in the mouse cortical wedge preparation and in the [3H]-flumazenil binding assay. Two of the plant extracts were investigated for anticonvulsive properties in the pentylenetetrazol (PTZ) kindling model in mice. Possible side effects on motor impairment were evaluated using the rota-rod test., Results: Extracts of 10 of the 11 medicinal plants showed affinity to the benzodiazepine binding site on the GABAA receptor. Seven of the 11 extracts inhibited the spontaneous discharges (SEDs) in the mouse cortical wedge preparation, with the extracts of Flueggea virosa and Psorospermum senegalense being the most potent. However, when tested for in vivo anticonvulsive properties these two extracts failed to show any effect on PTZ-induced seizures in mice., Conclusions: The pharmacological screening of the ethanolic extracts of 11 Malian medicinal plants in vitro lead to the identification of several extracts with potential anticonvulsant properties.

Aim of the Study: The present study is aimed to determine the bioactivity and structure of polysaccharides present in the leaves from the Malian medicinal plant Opilia celtidifolia [Guill. & Perr. Endl. ex Walp (Opiliaceae)]., Materials and Methods: The polysaccharides from the leaves of Opilia celtidifolia were isolated from water extracts of the leaves using gelfiltration and anion exchange chromatography giving the fractions Oc50A1 and Oc50A2. Monosaccharide composition was determined by gas chromatography of the derived TMS-derivatives of the methyl-glycosides. Linkages were determined of the partly methylated, partly acetylated alditol acetates obtained after a process including reduction, methylation, hydrolysis, reduction and acetylation followed by GC-MS. Effects on the complement system and the macrophages were determined using specific methods aimed for studying those activities., Results: The polysaccharide fractions isolated from the leaves of Opilia celtidifolia has high complement fixing activity and induce nitrite oxide release from macrophages in a dose dependent manner. The fractions had an ICH50 of 0.5 and 0.9 microg/ml respectively in the complement fixing assay. They induced the release of 7.2 and 7.3 microM of nitrite oxide from macrophages respectively at a dose of 100 microg/ml. The monosaccharide composition in Oc50A1 and Oc50A2, analysed, showed the presence of arabinose (26.7 and 13.2%), galactose (31.5 and 28%) and galacturonic acid (5.3 and 7.8%) respectively. The Yariv test confirmed the presence of arabinogalactan type II in both fractions. Structural analyses did also show the presence of terminal and 1-4 linked galacturonic acid and terminal and 1-2 linked rhamnose. Endo-polygalacturonanase treatment was performed to isolate the heavily substituted parts of the polysaccharides. These parts contained the same monosaccharides in similar proportion, and showed stronger dose dependent complement fixing activity and also stimulated macrophages to release nitrite oxide., Conclusions: The leaves of Opilia celtidifola contains polysaccharides of pectic type that have both complement fixing and macrophage stimulating activity.

Extracts of five medicinal plants: Boscia angustifolia, Cissus quadrangularis, Securidaca longipedunculata, Stylosanthes erecta and Trichilia emetica, used traditionally in Malian traditional medicine were screened for in vitro antiplasmodial activity and GABA(A)-benzodiazepine receptor binding activity. Four extracts showed significant antiplasmodial activities, with the dichloromethane extract of leaf of Securidaca longipedunculata being the most active (IC(50) of 7 microg/ml [95% CI: 5-9]). The dichloromethane extract of leaf of Trichilia emetica, in addition to its antiplasmodial activity (IC(50): 12 microg/ml [95% CI: 12-14]), exhibited a good binding activity to the GABA(A)-benzodiazepine receptor, while water and methanol extracts of the same plant did not show any activity. A strong GABA(A)-receptor complex binding activity was observed in the methanol extract of aerial part of Stylosanthes erecta. The results in this study justify some of the traditional indications of the plants investigated and may thus be candidates for Improved Traditional Medicines in Mali.

In material-resource poor countries like Mali, traditional practices incorporate the use of plants for medicinal purposes. Ethnobotanical research has documented traditional uses of plants, while concomitant studies by natural product chemists, ethnobotanists, and microbiologists have verified the efficacy of using traditional medicinal plants that have proven antimicrobial activity. These plants may also be used to protect agricultural crops pre-harvest and post-harvest from insect herbivory. In Mali, subsistence farmers, regional scientists, and extension specialists rely on local plants for many medicinal needs and are amenable to using traditional plant materials for insect pest management. The goal of this research was to develop Integrated Pest Management (IPM) strategies using Malian traditional medicine as a discovery lead. The discovery premise was based on identifying plants through a matrix approach utilizing agricultural scientists, traditional practitioners, and subsistence farmers. We hypothesized that plants used in traditional medicine with antimicrobial activity lead to potential insect pest management agents. To test our hypothesis, we developed a four-step process for selecting Malian plant species. Seven criteria were selected to create a systematic matrix to identify the most promising plant materials for practical, affordable, ecologically-sound insect management by Malian farmers. In the first step of the process, we developed a list of 294 medicinal Malian plant species which were evaluated using the matrix. Sixty-seven plant species met our main criteria. After the environmental soundness of these species was evaluated using four minor criteria, 50 species emerged from this pre-chemical, pre-bioassay process for further consideration in IPM programs in Mali.

Sixty-four extracts issued from twenty-one plants used in the Malian traditional medicine--several of them as antiparasitic drugs--were assayed for their antileishmanial effects against both extracellular and intracellular forms of Leishmania major. Seven extracts from six different plants--Sarcocephalus latifolius, Zanthoxylum zanthoxyloides, Entada africana, Bobgunnia madagascarensis, Pseudocedrela kotschyi and Psorospermum guineense--were found to be significantly active against the intracellular form of the parasite.

Extracts form 10 different Malian medicinal plants with a traditional use against schistosomiasis were investigated for their possible content of proteolytic activity. The proteolytic activity was studied by measuring the hydrolysis of two synthetic peptide substrates Z-Ala-Ala-Asn-NHMec and Z-Phe-Arg-NHMec. Legumain- and papain-like activities were found in all tested crude extracts except those from Entada africana, with the papain-like activity being the strongest. Cissus quadrangularis, Securidaca longepedunculata and Stylosanthes erecta extracts showed high proteolytic activities towards both substrates. After gel filtration the proteolytic activity towards the substrate Z-Ala-Ala-Asn-NHMec in root extract of Securidaca longepedunculata appeared to have Mr of 30 and 97kDa, while the activity in extracts from Cissus quadrangularis was at 39kDa. Enzymatic activity cleaving the substrate Z-Phe-Arg-NHMec showed apparent Mr of 97 and 26kDa in extracts from roots and leaves of Securidaca longepedunculata, while in Cissus quadrangularis extracts the activity eluted at 39 and 20kDa, with the highest activity in the latter. All Z-Phe-Arg-NHMec activities were inhibited by E-64 but unaffected by PMSF. The legumain activity was unaffected by E-64 and PMSF. The SDS-PAGE analysis exhibited five distinct gelatinolytic bands for Cissus quadrangularis extracts (115, 59, 31, 22 and 20kDa), while two bands (59 and 30kDa) were detected in Securidaca longepedunculata extracts. The inhibition profile of the gelatinolytic bands and that of the hydrolysis of the synthetic substrates indicate the cysteine protease class of the proteolytic activities. Several cysteine protease activities with different molecular weights along with a strong variability of these activities between species as well as between plant parts from the same species were observed.

In Mali the use of traditional medicine is a wide spread phenomenon, not only because of its cultural importance, but also as the majority of people cannot afford the western drugs or medicines. In Mali, the Office du Niger area constitutes the main zone of schistosomiasis transmission where both Schistosoma mansoni and Schistosoma haematobium are encountered. An ethnopharmacological survey, using questionnaire, was conducted in the Office du Niger area of the Niono District to determine the plants used against schistosomiasis amongst traditional healers. Forty healers from 21 villages of six different health areas were interviewed. All interviewed healers knew about urinary schistosomiasis, while only six knew about the intestinal form. The presence of blood in urine was reported as the main symptom of urinary schistosomiasis. Fifty-five plants belonging to 30 families were reported to be used alone for treating urinary and intestinal schistosomiasis, while nine combinations of plants were used against the urinary form of the disease. Cissus quadrangularis and Stylosanthes erecta were the plants most frequently used and were reported for the first time, to be used against schistosomiasis in Mali.

The African flora contains numerous medicinal plants whose biological and chemical properties are incompletely known. Antioxidant and radical scavenging properties of plants are subject to intensive research. In the work described here, we have investigated the antioxidant activity of the plants Diospyros abyssinica (root bark), Lannea velutina (root bark and stem bark) and Crossopteryx febrifuga (seeds). Extracts of different polarity were assayed for radical scavenging activity, using the stable free radical diphenylpicrylhydrazyl, and for inhibition of enzymatic lipid peroxidation mediated by soybean 15-lipoxygenase. All plants investigated showed activity, but there were large differences between plants and between extracts. In general, Diospyros abyssinica and Lannea velutina were richer in antioxidants than Crossopteryx febrifuga. Lipophilic extracts were not active as radical scavengers, but did inhibit 15-lipoxygenase. Semipolar extracts (80% aqueous ethanol and methanol) of Diospyros abyssinica and Lannea velutina showed the highest activity both as radical scavengers and lipoxygenase inhibitors, and also gave the highest extract yields. These plants therefore appear to be excellent sources of antioxidants.

Water, methanol and dichloromethane extracts prepared from various parts of 40 medicinal plant species from Mali were investigated for their trypanocidal activity against Trypanosoma brucei brucei. Of a total of 165 extracts tested in vitro in the Low Inoculation Long Incubation Test (LILIT), 24 extracts showed a high trypanocidal activity. Using the Long-Term Viability Assay (LtVA) for corroboration of the results of the 24 extracts, it was found that 15 samples had minimum inhibitory concentration (MIC) values > 10 microg/ml, eight MIC values of 100 microg/ml and one MIC values of 50-100 microg/ml. So far, four extracts with MIC values < or = 100 microg/ml were tested for antitrypanosomal activity in mice, experimentally infected with Trypanosoma brucei brucei. Only, the aqueous extracts of the leaves of Terminalia avicennioides Guill. and Perr. (Combretaceae) and the stem bark of Ceiba pentandra (L.) Gaertn. (Bombacaceae) were able to reduce the parasitaemia in animals treated at the dose of 100 mg/kg b.w. (intraperitoneally, two times daily for 3 days) and of 150 mg/kg b.w. (per os, two times daily for 3 days), respectively. The reduction of parasitaemia was, however, statistically significant (p=0.002) only in case of treatment with Terminalia avicennioides.

Glinus oppositifolius (L.) Aug. DC. (Aizoaceae) is a Malian medicinal plant used against various types of illnesses related to the immune response, like joint pains, inflammations, fever, malaria and wounds. Two pectin type polysaccharides, GOA1 and GOA2, being isolated from a 50 degrees C water extract from the aerial parts of Glinus oppositifolius were investigated for their activity towards the complement system and different leukocyte subsets because of the assumed effects on conditions related to the immune system. The polysaccharide polymer in GOA1 was shown to contain considerable amounts of the neutral sugars arabinose (26.4 mol%) and galactose (42.9 mol%), and methylation analysis indicated the presence of arabinogalactans type I (AG-I) and type II (AG-II). GOA2 was rich in galacturonic acid (68.3 mol%), along with rhamnose, arabinose and galactose. Structural studies indicated that rhamnose and galacturonic acid might constitute a rhamnogalacturonan backbone, often found in pectic substances, with side chains consisting of arabinose and galactose. Both GOA1 and GOA2 were shown to exhibit potent dose-dependent complement fixating activities, and induced chemotaxis of macrophages, T cells and NK cells.

Cochlospermum tinctorium A. Rich. (Cochlospermaceae) is a widely used medicinal plant in the West African country, Mali. An ethnopharmacological survey was conducted and 106 traditional practitioners interviewed. The roots were the part of the plant reported to be the most frequently used for medicinal purposes. The main indications were to treat jaundice (41), gastro intestinal diseases or ailments (28), malaria (12), schistosomiasis (10) and dysurea (6). A high-molecular weight water extract (25, 50 and 100 mg/kg, body weight) significantly inhibited HCl/ethanol-induced gastric lesions in mice. The extract showed DPPH-radical scavenging- and immunomodulating activities in vitro. The main components of the extract were identified as polysaccharides (59.3%) and polyphenols (9.3%). The polysaccharides were purified and characterised as highly complex pectic arabinogalactans type II. As parts of the polyphenol compounds gallotannins and ferulic acids were identified. This study shows that the polysaccharides are partly responsible for the bioactivities observed in vitro. Both polysaccharides and polyphenols may be responsible for the anti-ulcer activities observed.

In Mali, the empirical knowledge on plant medicine is held by traditional practioners. Scientific studies have been carried on some plants and they have confirmed their local uses, but few data are available on the toxicity of Malian medicinal plants. In the present work, we record the toxic plants used as medicines in the Bamako district, Mali, with the aim to evaluate the knowledge of traditional healers and herbalists on the toxicity of the plant used. A survey was carried out on the market places in the Bamako district and 106 healers and herbalists were interviewed. A survey of the scientific literature was conducted to verify or sustain the claimed toxicological data. Nineteen plants are arranged according to their frequency of quotation based on the questionnaire. The information includes the botanical name, literature survey on the pharmacology of the plants, the healers' knowledge on plant toxicity and its prevention by some of the healers.

Traditional medicine, being a significant element in the cultural patrimony, still remains the main recourse for a large majority of people in Dogonland, Mali, for treating various diseases and ailments. This paper reports an ethnopharmacological study in Dogonland with the aim to identify medicinal plants used in the treatment of wounds. Information obtained from traditional healers revealed 73 plant species being used as wound healing remedies, according to the definitions of wounds given by the healers themselves. The plants, belonging to 34 plant families, are used as first aids, in the washing of wounds, extraction of pus, as coagulants, as well as for infected wounds. The most frequently used preparations are decoctions and powdered plant material.

The roots from Vernonia kotschyana Sch. Bip. ex Walp. (Baccharoides adoensis var. kotschyana (Sch. Bip. ex Walp.) M.A. Isawumi, G.El-Ghazaly & B. Nordenstam) (Asteraceae) are used in Malian folk medicine for the treatment of gastritis, gastro duodenal ulcers, as an aid to ameliorate digestion and as a wound healing remedy. Since a common feature among these conditions is related to immune responses, immunomodulating activities of fractions isolated from both the 50 degrees C and the 100 degrees C water extracts from Vernonia kotschyana were investigated in this study. The active principles were identified as acidic polysaccharide fractions, containing pectic arabinogalactan type II structures, which showed both complement fixing ability and T-cell independent induction of B-cell proliferation in vitro. Some activity was also observed on macrophages. The present study may provide additional support for the popular use of this plant to improve intestinal health.

Trichilia emetica is a tree or bush that has many different traditional uses in Mali, amongst others the leaves have been used as a woundhealing remedy. As polysaccharides have been isolated from other plants that have a long tradition as woundhealing remedies, it was of interest to study the polysaccharides of T. emetica as well. The polysaccharides were extracted at 50 and 100 degrees C, and the polymeric material was separated into neutral and acidic polymers by anion exchange chromatography. The complement fixation ability of the different fractions was determined. The Acidic fraction 4 of the 100 degrees C extract was the most active, but most of the other fractions were also quite active. Structural studies showed that the most active fraction was a pectin of the rhamnogalacturonan type 1 with side chains of the arabinogalactan type II. Removal of terminal arabinofuranosides lead to a drop of the activity indicating that this structural unit may be involved in the bioactive site of the molecule., (Copyright 2002 Elsevier Science Ireland Ltd.)

Entada africana is a tree used in traditional medicine in Mali. The root is, for example, used for wound-healing. Since polysaccharides from other plants are thought to play a role in the wound-healing process, we wanted to study the polysaccharides present in the root of this species. The polysaccharides were extracted with water at 50 and 100 degrees C and were further separated by anion exchange chromatography. The acidic fractions were finally purified by affinity chromatography on a Con A column. The fraction denoted Ea100 acidic I had the highest activity in the complement fixation test system, while the other acidic fractions had minor activities and the neutral fractions were almost negative. Ea100 acidic I has a structure resembling the arabinogalactan-protein type II polymer, which also was demonstrated by the abilities to precipitate with the Yariv reagent. The biological activity was reduced considerably after removal of arabinofuranoside residues by weak acid hydrolysis. The main core of the other polysaccharides extracted with 100 degrees C were pectins resembling the rhamnogalacturonan type I. These fractions also contain arabinogalactan type II structures, shown by the formation of precipitates with the Yariv reagent.