In order to constrain the structural evolution in the central part of Burkina Faso and its implication for the emplacement of gold deposits, we undertook a structural mapping by coupling Landsat and aeromagnetic images interpretation to outcrop and core mapping followed by laboratory work. This approach reveals that the structural architecture in this locality mainly results from dextral transcurrent progressive deformation due to a NW-SE trending major stress. This architecture is similar to the Riedel-Tchalenko model. Initially, the dominant normal stress created an E-W constriction resulting in the development of N-S shear corridors. Subsequently, the tangential stress that took over this generated the progressive development of simple dextral shear zones with a NE-SW orientation that are locally taken up by ENE-WSW dextral shear bands associated with the Riedel's R structures. As a result of the cooling of the crust, we are witnessing the formation of sinistral NW-SE and dextral NNE-SSW strike-slip faults, respectively, which corresponds to Riedel's R' structures and Tchalenko's P structures. The development of NW-SE pre-Eburnean shear zones, particularly the N-S shear corridors, is synchronous with the circulation of gold-bearing fluids through the zone. However, the intersections of these directional corridors create zones suitable for gold concentration. Within these zones, ductile-brittle deformation following the emplacement of the shear bands has facilitated the remobilization and concentration of gold-bearing fluids within rocks with the appropriate rheological conditions. This is the case for Toega gold deposit.

The Lom Pangar dam, the largest reservoir in Cameroon with a storage capacity of 6 km3 and a 30 MW hydropower plant, primarily regulates the hydrologic regime of the Sanaga River to maintain hydropower efficiency during dry seasons and enhance downstream hydropower plant performance. Understanding and managing sediments are crucial for the sustainability of dams, as indicated by numerous studies. This study assessed the granulometry of the sediments transported across the reservoir. For that purpose, 6 samples of fresh sediments were collected in the lacustrine and transitional sections of the reservoir using the standard method. Particles size was assessed using the laser diffusion technic after a 3 mm sieving. Various granulometric parameters were derived from the literature to analyze and characterize those sediments. Results show that silts are more than 70% of particles size and range between 2.19 - 60.26 µm. Size distribution also shows the same trend with D75 less than 51 µm. This is confirmed by the low values of Inman Skewness SkΦ (−0.168 to 0.303). The Sorting index S0 ranges from 0.31 to 0.53 µm, showing a very well-sorted sediments, aligning with low values of Krumbein index (0.906 - 1.683) that express the low heterometry of the particles. The consequence on the dam will be a quick clogging of the bottom of the reservoir. Their pH varies from 7.0 to 7.5. It also appears that the sandy fraction trend is higher in the right bank of the dam and reaches 22% on the right bank of Pangar River due to crystalline geology. Fraction greater than 3000 µm is negligible. The management of the dam has to keep attention to these results as siltation may close the safety outlet of the dam, damage turbines, and provoke recurrent technical and safety issues. Further, the clogging of the bottom of the reservoir may lead to an ecological problem with the limitation of hyporheic flow. Thus, water exchange with the underground water table and the natural purification of water reduce, while increasing sediments deposits change the biogeochemistry processes.

Surface water resources are stored in reservoirs in Burkina Faso. They are actually more efficient cost-benefit than groundwater, given unsuccessful drilling and arsenic contamination of boreholes. There is a need to reconsider the surface water as main water sources. However, their extents are impacted by climate change and living creatures uses. This study monitored the water extend variation in dams and lakes between 2017 and 2023, using sentinel-2 satellite. The Modified Normalized Difference Water Index was simulated using the Python based algorithm of Digital Earth Africa. It processes over 400 images with good pixels on each of 32 chosen reservoirs, then calculates the “gain” or “loss” of water surface. Results show that water surfaces are increasing in the country. Amongst the critical cases, Kompienga hydroelectric dam reveals an increase of 80.18% (82.33 / 102.67 km 2 ) of newly area occupied by water. Such situations can lead to a dam breakdown.

Abstract Predominant volcano-plutonic (mafic–felsic) activity is expressed in the eastern Banfora Belt. The geochemical signature shows different geodynamic settings: (1) mafic rocks are tholeiitic, subalkaline and show high-Mg tendency, whereas pyroxenolite (MgO c. 15.4 wt%) has komatiite affinity; (2) felsic volcanic rocks are subalkaline; and (3) granitoids surrounding the Banfora Belt are alkaline to calc-alkaline, high K, peraluminous to metaluminous. The geochemistry of mafic volcanic rocks shows an unusual evolution from Mid Oceanic Ridge Basalt to Arc-related. The Western Granite and Eastern Granites were emplaced by fractional crystallization and partial melting, respectively, but sourced from igneous protolith (I-type magma) in a volcanic arc setting. The Sodingue granite was emplaced by fractional crystallization from A-type magma in a ‘within-plate setting’. Two-mica S-type granites located at the central portion of the belt relate to syn-collisional fractional crystallization. The paper highlights the complexity of the magma process through a diversity of sources, geochemical patterns and tectonic settings. An emphasis on the komatiite affinity of mafic magma is a challenge for related commodities, such as copper and gold resources.

The Belahourou granite pluton (BG pluton) is a magmatic body that belongs to the Djibo greenstone belt, north Burkina Faso. Calc-alkaline in composition and 2132 +/- 4 Ma in age (U-Pb zircon), this pluton is bordered by the curved Belahourou-Souma (BS) sinistral shear-zone, NNW-trending in the northern half of the pluton and WNW-trending in the southern part. In order to study the emplacement mechanism relationships with the BS shear-zone and the gold-deposits, the pluton and its host-rocks have been subjected to standard and modern mapping techniques (airborne geophysics, satellite imagery, anisotropy of magnetic susceptibility - AMS - and microstructural observations), in addition to field observations. The pluton, 100 km(2) in area, 16 km in length and 7 km in width, is surrounded by metamorphic formations, turbiditic clastic to the west and volcanic material along the southern and eastern sides. To the north the pluton is in contact with granodioritic and gabbroic rocks. Pluton emplacement was likely instigated by opening of a tension gash associated with NW-directed, sinistral shearing along the curved BSS. The overall NW-trending magnetic lineations inside the pluton support this interpretation. The microstructures indicate that shearing continued during pluton cooling, explaining the inside-pluton magmatic to orthogneissic transition, and after cooling, explaining the mylonitic microstructures against the BS shear-zone. A 3D conceptual representation integrates the available data and concludes that the pluton is late-tectonic with respect to the regional D2 deformation event. Once emplaced, the pluton may have provided low pressure zones, at lithological contacts and/or inside brittle fractures in the host formations, concentrating the mineralizing fluids that were pressurized during pluton cooling, and that helped to precipitate the ore. (C) 2018 Elsevier Ltd. All rights reserved.

Moringa oleifera (LAM), arbre tropical a usages multiples, constitue de nos jours une nouvelle ressource alimentaire et economique pour les pays du Sud. Ces feuilles sont faciles d’acces et tres riches en proteines, en vitamines et en mineraux. Elles sont de plus en plus utilisees dans des projets luttant contre la malnutrition. Cependant, le gout, la presentation et la qualite de ces produits demeurent une preoccupation majeure necessitant des adaptations innovantes. L’objectif de cette etude etait d’etudier la comprimabilite des poudres de feuilles de Moringa oleifera en ameliorant le gout avec des matieres premieres locales et facilement accessibles comme la poudre de pulpe de Andansonia digitata. Les proprietes physico-chimiques et les tests pharmacotechniques ont permis de controler la qualite des poudres, des comprimes et orienter le choix du procede de fabrication. Cinq (5) types de formulations (F1 a F5) ont ete realises et les comprimes ont ete fabriques par compression apres granulation par la voie seche. Les comprimes des formulations F4 et F5 ont donne de meilleures proprietes pharmacotechniques selon les recommandations de la pharmacopee Europeenne 6.0. L’association des deux poudres offre une alternative pour la fabrication de comprimes a croquer avec un gout acceptable.Mots-cles : Moringa oleifera, Adansonia digitata, poudre, comprime, controle qualite.

The Inata cluster of gold deposits is one of ten gold deposits currently in exploitation in Burkina Faso. The aim of this work was to assess the influence and contribution of the magmatic events in the metallogenic system. Our approach is based on detailed field observation and petrography of different lithologies encountered in the main pit (NP). The intrusions were targeted and reasonably, six types were described: (i) gabbro, (ii) porphyrytic diorite, (iii) foliated intrusion, (iv) quartz-feldspar (micro) diorite, (v) dacite, (vi) fine grained diorite. No clear relationship was established between gabbro and the mineralization but quartz ± feldspar dioritic and dacitic compositions may have contributed in fluid remobilizing, some of which developed pressure shadow with optimal energy. Inata has been described as mesothermal gold deposit. The series of intrusions as we have interpreted may help in the understanding of the several episodes of gold mineralization at Inata. In summary, this paper is a contribution that highlights the closeness of the magmatic bodies in relationship with the gold deposit in that part of the Birimian terrane. We think this could help in enhancing interest for some other similar environment in Burkina Faso, particularly when supported with whole rock analysis.

Twenty years after the discovery of the Perkoa Zn-Ag deposit, another type of Zn-Cu-Pb +/- Ag Volcano genic Massive Sulfide (VMS) subgroup of occurrences forming a district has been highlighted within the Paleoproterozoic Birimian Greenstone Belts of the West African Craton in Burkina Faso. The geology of the area is characterized by a series of dominantly mafic volcanic rocks with intercalated black shales which increase in proportion upwards in the stratigraphy. This stratigraphic package is overlain by a felsic volcanic sequence comprising reworked tuff and rhyolite. Although mineralization is locally associated with sedimentary rocks, it is more commonly found in rhyolites. The metamorphic grade is dominantly greenschist facies. The main lithologies in the mafic sequence range from basalt to andesite with associated gabbro. The felsic sequence consists of dacite to rhyolite with associated granitoids (granite-granodiorite-tonalite). The volcanic rocks are commonly tholeiitic (Zr/Y = 2-4.5) with relatively high Zr and Y content, although a limited number of samples plot in transitional (Zr/Y = 4.5-7) or calc-alkaline (Zr/Y = 7-25) fields. Rhyolites, which constitute the main mineralized rocks at Tiebele, have similar key trace element signatures to other rhyolites-related known VMS systems worldwide. Both have low Zr/Y (<7) and low La-N/Yb-N (<6), which suggests low crustal residence times of magmas in extensional settings. Detailed investigations identified at least four VMS targets notably at Koubongo, Nabenia, Loubel and AW (Amenagement de la Vallee des Voltas) extending over an area of 332 km(2). Typical mineral assemblages defining VMS occurrences are mainly hosted by meta-sedimentary rocks and rhyolite but are also found as veins in tonalite. These assemblages can be grouped into four different styles: (i) Variably banded massive sulfides dominated by sphalerite over galena, pyrite, and chalcopyrite within metasediments; (ii) Pyrite-rich or pyrrhotite banded type associated with sphalerite, chalcopyrite, and galena within silicified and carbonatized units; (iii) Disseminated and finely oriented sulfides, including pyrite - pyrrhotite - magnetite +/- sphalerite within quartz-phyric rhyolite; and (iv) Fracture filling pyrrhotite-rich - magnetite - sphalerite mineralization possibly within tonalite. Irrespective of the style of the mineralization, chemistry of altered and least altered rhyolite reveals a significant increase in Mg +/- Fe and H2O, and a loss of K within mineralization associated alteration. This may suggest sea water leaching of underlying (7) mafic and sedimentary rocks, with Mg Fe transfer into the rhyolites concomitant with the loss of K. This paper highlights the features of new occurrences of VMS mineralization type within the Birimian system of West Africa. We think this could help for new discoveries along the belts. Exploration based upon ground mapping, geochemistry and geophysics is highly recommended. (C) 2017 Elsevier Ltd. All rights reserved.

Aim: To investigate the cytotoxic effect of methanol extract of Ptreocarpus erinaceus stem barks against cancer lines (Leukemia cell K562 and lung small cells A549) and its inhibition effects against NF-kappa B activation and lipoxygenase enzyme. Moreover, phenolic compounds, tannins and flavonoids amounts have been determined.Study Design: In vitro evaluation of cytotoxic activity, inhibitor effect against NF-kappa B activation and lipoxygenase; and quantitative determination of total phenolic contents.Place and Duration of Study: Laboratory of Departement de medecine-pharmacopee traditionnelle and Laboratoire of Biologie Moleculaire et Cellulaire du Cancer (February November 2013). Methodology: The cytotoxicity of methanol extract from stem bark of this plant against cancer cell lines (Leukemia cell K562 and lung small cells A549), and its inhibition of NF-kappa B activation in K562 cells and lipoxygenase were studied. Additionally phytochemical composition including phenolic, tannins, flavonoids and flavonols was determined by using standard methods.Results: At 50 mu g/mL, the methanol extract of P. erinaceus inhibited the growth of K562 and A549 cells with inhibition percentage of 46.2 +/- 4.0 and 59.4 +/- 4.5% respectively. Extract inhibited NF-kappa B activation at 50 mu g/mL (86.5 +/- 2.7%), and lipoxygenase activity was significantly inhibited by extract at 100 mu g/mL (97.7 0.5%). Phytochemical analysis shows the presence of phenolic compounds, tannins, flavonoids and flavonols in a methanolic extract of Pterocarpus erinaceus stem bark.Conclusion: Pterocarpus erinaceus stem bark showed significant cytotoxic effect and inhibited NF-kappa B activation and lipoxygenase. These pharmacological effects could be due to the presence of phenolic compounds, tannins, flavonoids and flavonols.

Saba senegalensis (A. DC.) Pichon with synonymous Landolphia senegalensis (A. DC.) Kotschy & Peyr. (Apocynaceae) is a lianescente plant used in traditional medicine for the treatment of diseases with inflammatory components in Burkina Faso. The objective of this study was to test the pharmacological action of the aqueous extract of its leafy stems on swelling, pain and to assess its antioxidant properties. The aqueous extract reduced edema in the first hour, the third hour and five hours after the injection of carrageenin. Maximum inhibition was achieved at the fifth hour after the injection of the carrageenin. The analgesic effect of the aqueous extract of S. senegalensis at doses of 100, 200, 300 mg/kg was evaluated by the method of Koster after injection of acetic acid. The results showed that the aqueous extract reduced significantly (p <0.05) and in dose-dependent manner the abdominal writhing in NMRI mice. The analgesic effect of the aqueous extract at a dose of 200 mg/kg is comparable to that of acetaminophen (150 mg/kg). The study of aqueous extract in vitro showed a significant antioxidant capacity by inhibition of DPPHradical (IC50=18.4 μg/ml), lipid peroxidation (79.22%) and lipoxygenase (93.26%). The phytochemical screening revealed the presence of tannins, flavonoids, saponins, coumarins, anthocyanosides, triterpenes and sterols. These results show that the leafy stems of S. senegalensis have anti-inflammatory properties and justify the use of the plant in traditional medicine against inflammatory diseases.

Pterocarpus erinaceus Poir. (Fabaceae) est une plante médicinale utilisée dans la prise en charge de nombreuses pathologies dont les maladies à composante inflammatoire. L'objectif du travail était d'étudier les effets anti-inflammatoire, analgésique et antipyrétique des décoctés aqueux des feuilles et des écorces de racines de Pterocarpus erinaceus afin de valoriser son utilisation en médecine traditionnelle. Aux doses de 200, 400 et 600 mg/kg les décoctés aqueux des feuilles et des écorces de racines ont réduit significativement l'oedème de la patte de la souris induit par la carragénine et les contractions abdominales produites par l'injection de l'acide acétique chez la souris. Les deux extraits ont inhibé les deux phases de douleur produites par la solution de formaldéhyde. L'hyperthermie induite chez la souris par la levure de bière a été réduite par les deux décoctés aqueux, cet effet reste cependant plus marqué pour les feuilles que les racines. Le criblage phytochimique des extraits a permis de mettre en évidence la présence de tanins et polyphénols, de flavonoïdes, de saponosides, de triterpènes et stéroïdes, qui pourraient être responsables des propriétés pharmacologiques.

Ficus sur and Ficus sycomorus , two medicinal species used in Burkinabe traditional medicine for the treatment of sickle cell disease were investigated. The determination of total phenolic and tannins contents, using the method of Folin-Ciocalteu (FCR), indicate values significantly (p <0.05) higher in extracts of Ficus sycomorus compared to those of Ficus sur , with respective values of 336.80 ± 0.80 mg TAE/g of extract and 203.74 ± 0.9 mg TAE/g of extract against 247.00 ± 0.52 mg TAE/g of extract and 120.8 ± 0.83 mg TAE/g of extract. Similarly, using the method of 1,1-diphenyl-2-picrylhydrazyl (DPPH), the results of the analysis indicate that extracts of Ficus sycomorus produce the highest antiradical activity with IC 50 value of 9.60 ± 0.02 μg/mL against 31.83 ± 0.55 μg/ mL for Ficus sur. The IC 50 value of quercetin, used as reference antioxidant, was of 4.6 ± 0.08 μg/mL. The latex of Ficus sycomorus presented the lowest minimum inhibitory concentrations (MIC) against Staphylococcus aureus and Escherichia coli , with respective values of 0.13 mg/mL and 0.25 mg/mL. The difference in phenolic content could explain the difference in biological activity between the two Ficus species. Keywords : drepanocitosis, radical scavenging, tannins, flavonoids, medicinal plants

Root bark extracts from Zanthoxylum zanthoxyloides Lam (Rutaceae) and Calotropis procera Aït (Asclepiadaceae) were used in Burkina Faso folk medicine for several diseases particularly sickle cell anemia. Authors reported here vasorelaxant effect of these plants on rat isolated aorta. Z. zanthoxyloïdes (cumulative addition) produces a concentration-dependent relaxation on the aorta. Maximal effects are respectively of 60.34 ± 2.34 and 100% in the presence and in the absence of endothelium. C. procera extract induces a more relaxing effect on endothelium-denuded aorta (Emax = 59.78 ± 2.13% and 100% in presence and absence of endothelium respectively). FACA, the mixture of these two plants also induces vasorelaxation (Emax = 100%), with better effect in the presence of endothelium (EC50 = 2.76 ± 0.38 mg/mL and 4.90 ± 0.69 mg/mL in presence and absence of endothelium respectively). Endothelium-dependent vasodilator effect of FACA was inhibited by L-NAME; this clearly indicates that NO is involved in aorta relaxation process by FACA. Taken together this study revealed that FACA and its components possess vasodilator effect. This vascular property of FACA may be involved in the amendment of sickle cell crisis through inhibition of vaso-occlusion process.Keywords: Sickle cell anemia, phytotherapy, rat aorta, endothelium

The anti-inflammatory, antipyretic, and pro-apoptotic properties of extracts of Borassus aethiopum have been reported in the literature. In this study, we investigated the antifungal and antibacterial properties of Borassus aethiopum male inflorescences extracts. The antifungal and antibacterial activity was studied by agar well diffusion method in vitro. The effect of antibacterial potential was examined against Gram positive bacteria (Staphylococcus aureus), and Gram negative bacteria i.e., (Escherichia coli and Enterobacter cloacae). In the antifungal activity assays, the dermatophytes strains Trichophyton rubrum, Trichophyton interdigitale, Trichophyton soudanense, Microsporum langeronii, and Epidermophyton floccosum were used. The E2F2 extract showed strong inhibitory activity on four of the five fungal species used against ketoconazole, a standard antifungal drug. However, the E2F2 extract displayed weak antibacterial activity against the bacterial strains tested. The results of the present study support the ethnomedicinal uses of Borassus aethiopum for the treatment of fungal diseases. The phytochemical screening of E2F2 extract revealed the presence of sterols, triterpenes and saponins, witch may be involved in the antifungal activity. KEYWORDS : Antifungal, antibacterial, Borassus aethiopum

Borassus aetihiopum MART (Arecaceae) is a plant used in traditional herbal medicine for the treatment of various diseases (bronchitis, laryngitis, antiseptic). In particular, their male inflorcscences were reported to exhibit cicatrizing, antiseptic and fungicidal properties. In the present study, the biological activity of E2F2, an apolar extract from Borassus aethiopum male inflorescence was investigated on colon cancer HT29 cells. Phytochemical screening was carried according to methodology for chemical analysis for vegetable drugs. Cells proliferation was determined by the MTT assay and cells cycle distribution was analysed by using laser flow cytometer (Beckman coulter). The cytoskeleton organisation was examined under a laser scanning confocal microscope (Zess). Preliminary phytochemical analysis of E2F2 extract revealed the presence of sterols, triterpenes and saponosids. E2F2 extract (1 microg and 100 microg mL(-1)) significantly inhibited cell proliferation by blocking cell population in G0/G1 phase. Flow Cytometric analysis of E2F2-treated HT29 cells showed that hypoploïd cell population (sub G1 phase) increased with processing time exposures. Immunofluorescence confocal analysis revealed a disrupt actin microfilaments network in E2F2 treated-cells with a significant reduction in actin stress fibres and appearance of a random, non-oriented distribution of focal adhesion sites. These data indicate that E2F2 extract has anti-proliferative and pro-apoptotic activities. Further studies are required to unravel the mechanisms of action of E2F2 extract.

The aqueous extract of Pterocarpus erinaceus stem bark was investigated for its anti inflammatory, analgesic and antioxidant activities. The phytochemical screening using standard procedures of analysis revealed the presence of tannins, flavonoids, saponins, triterpenoids and steroids The antioxidant test using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and cupric-reducing antioxidant capacity (CUPRAC) methods demonstrated important radical scavenging activity with the antiradical power (ARP) of 1.25 (in DPPH method), and trolox equivalent antioxidant capacity (TEAC) = 0.7. At the doses of 200, 400 and 600 mg. kg(-1) body weight orally, the aqueous extract of P. erinaceus produced significant analgesic effects in acetic acid-induced writhing and hot plate methods. At the doses of 300 and 500 mu g/ear, the aqueous extract reduced inflammatory process in croton oil-induced ear edema and carrageenan-induced paw edema methods. These results suggest the possibility of using P. erinaceus in the treatment of painful and inflammatory conditions.