Isolement et caractérisation morphologique de moisissures productrices de substances antibactériennes à partir d’aliments locaux au Burkina Faso

En vue du risque augmenté jour après jour des bactéries résistantes aux antibiotiques, nous nous sommes intéressés dans cette étude à l’isolement et à la caractérisation des isolats de moisissures productrices d’antibiotique à partir d’aliments locaux du Burkina Faso. Cinquante (50) isolats fongiques isolés ont servis au test d’antibiose qui a révélé vingt (20) isolats producteurs de substances antimicrobiennes. Ce test a concerné les cellules des isolats ainsi que des extraits aqueux et organiques issues de ceux-ci. Trois (03) isolats ont présenté des diamètres d’inhibitions moyens de 20 mm sur les germes tests. Leur caractérisation a porté sur les critères morphologiques et culturaux. L’isolat S1 présente en 5 jours d’incubation sur la gélose de Pomme de Terre Dextrose (PDA) une colonie plate, de couleur blanche au recto, avec un revers jaune, l’isolat S2 une colonie vert-olive, de texture veloutée, plus dense au centre et l’isolat S3 une petite colonie de couleur verte et ronde. En microscopie optique les isolats S1 et S2 ont présenté des conidies rondes, réfringentes et nombreuses, les conidiophores sont hyalins, longs et non cloisonnés. L’isolat S3 a présenté des conidies rares, des pénicilles constitués de phialides branchés directement à l’extrémité des conidiophores cloisonnés. L’analyse de ces caractéristiques indique que S1, S2 et S3 appartiennent respectivement aux genres Aspergillus et Penicillium.© 2016 International Formulae Group. All rights reserved.Mots clés: Substances antimicrobiennes, Aspergillus, Penicillium, Burkina FasoEnglish Title: Isolation and morphological characterization of fungi producing antibacterial substances from local food in Burkina FasoEnglish AbstractBacterial resistance to the actual antibiotic is mostly in dangerous progress, why we have interest in isolation and characterization of fungi strains producing antibiotics using local food in Burkina Faso. Fifty (50) isolated strains were used in the antibiosis trial which revealed twenty (20) strains producing antimicrobial substances. This trial concerned the strains cell as well as its aqueous and organic extracts. Three (03) strains had average inhibition diameters of 20 mm on the testing germs. Their characterization focused on the  morphological and culture criteria. After five days of incubation in Potato Dextrose Agar (PDA), the strain S1 shows a flat colony, white on the front, with a yellow reverse. The strain S2 shows an olive-green colony, velvety texture, more dense in the center. As for the strain S3, it shows a round green colored colony. In optical microscopy, strains S1 and S2 showed numerous round and refractive conidia, conidiophores are hyaline, long and not partitioned. S3 strain showed uncommon conidia, penicillus made of phialides which are directly linked to the end of partitioned conidiophores. Analysis of these characteristics indicates that S1, S2 and S3 belong respectively to the Aspergillus and Penicillium genera.© 2016 International Formulae Group. All rights reservedKeywords: Antimicrobial substances, Aspergillus, Penicillium, Burkina Fas

Optimisation de la production de biométhane à partir des déchets organiques municipaux

La gestion des déchets municipaux est devenue une préoccupation majeure dans les pays en développement, due au manque de politique et de stratégie adaptées. L’étude réalisée a porté sur la valorisation biotechnologique de la fraction biodégradable des déchets au Burkina Faso. Une analyse physico-chimique des déchets échantillonnés dans trois (3) centres de précollecte de déchets municipaux de Ouagadougou a été réalisée. L’influence du type d’inoculum (eaux usées, bouse bovine, flux de broyat de termites et une mixture de ces 3 inocula) et de la charge en substrat (déchets organiques) a été évaluée au cours d’essais de fermentation méthanique. Les résultats obtenus ont montré que les déchets organiques municipaux constituent un substrat de prédilection pour la méthanisation avec un ratio C/N de 31,65. Les essais de fermentation ont permis de noter que la bouse bovine comme inoculum avec une charge en déchets municipaux de 2% donnait la meilleure production de biométhane (297,65 l CH4 / Kg MSV). Il ressort de cette étude que les déchets municipaux peuvent être traités par la voie de la biométhanisation car présentant un potentiel de bioconversion intéressant.© 2015 International Formulae Group. All rights reserved.Mots clés: Déchets organiques, digestion anaérobie, biométhane, environnement, Burkina FasoEnglish Title: Optimization of biomethane production from municipal solid organic wastesEnglish AbstractMunicipal solid organic wastes management became a major preoccupation. The achieved study focuses the biotechnological valorization of the biodegradable fraction of solid organic wastes in Burkina Faso.  Physicochemical characterization analysis of solid wastes sampled in 03 Ouagadougou’s centers of municipal wastes deposits was achieved. The influence of inoculum source (wastewater, bovine dung, termites’ homogenate and mixture) and substrate concentration (municipal solid waste) were evaluated during biomethane production tests. Results showed that organic fraction of solid wastes represent a source of predilection for methanization with 31.65 C/N cow. Fermentation tests showed that bovine dung used as inoculum in 2% of municipal solid waste gave the highest rate of biomethane production (297.65 l CH4 / Kg vs). The results demonstrate that municipal wastes can be valorized by biomethanization way because presenting interesting bioconversion potential.© 2015 International Formulae Group. All rights reserved.Keywords: Organic wastes, anaerobic digestion, biomethane, environment, Burkina Fas

Etude de l’évolution des éléments précurseurs d’eutrophisation des eaux du Barrage n°3 de Ouagadougou, Burkina Faso

Dans le cadre du suivi de la qualité des eaux de surface destinées à la potabilisation, l’évolution des éléments précurseurs d’eutrophisation (matières azotées et phosphorées) du barrage n°3 de Ouagadougou a été investiguée durant la période de septembre 2012 à décembre 2012. Les paramètres chimiques ont été déterminés par spectrophotométrie d’absorption moléculaire et les paramètres physiques par la méthode électrochimique. Les analyses physicochimiques ont mis en évidence des corrélations entre la teneur en nitrates et la chlorophylle A (r = 0,715) et entre la température et la chlorophylle A (r = 0,838). La teneur en orthophosphte est faiblement corrélée avec la teneur en chlorophylle A du barrage (r = 0,171). Il n’a été observé aucune différence significative entre les concentrations en orthophosphates des quatre mois de la période d’étude (p<0,05). La plus forte valeur (1,3 mg/l) a été observée au cours du mois de septembre et la plus faible valeur (0,14 mg/l) au cours du mois de novembre. Cependant, les teneurs en nitrates, température et chlorophylle A des eaux étaient plus fortes au cours du mois d’octobre (respectivement, 6,6 mg/l; 29,14 °C ; 0,04 μg/l) et plus faibles en décembre (respectivement, 3 mg/l ; 23,25 °C ; 0,02 μg/l). Ces résultats indiquent que les mois d’octobre et novembre sont des périodes à risque d’eutrophisation du barrage n°3 de Ouagadougou. Il ressort des résultats que l’eau du barrage est de bonne qualité au plan physico-chimique et revêt un état trophique oligo-mésotrophe.© 2016 International Formulae Group. All rights reserved.Mots clés: Eutrophisation, chlorophylle A, état trophique, nitrates, température, barrage n°3 de OuagadougouEnglish Title: Study of eutrophication’s precursors items of Ouagadougou’s 3rd dam’s waters, Burkina FasoEnglish AbstractIn a framework of monitoring the quality of surface water intended for drinking, the evolution of eutrophication’s precursors (nitrogenous substances and phosphorus) of Ouagadougou’s third (rd) dam has been done in the standard base period from September 2012 to December 2012. The chemical measures have been determined by molecular absorption spectrophotometry method and the physical parameters by electrochemical method. The physicochemical tests underlined interrelated the relationship between nitrate content and the chlorophyll A (=0.715) and between the temperature and chlorophyll A (r=0.838).The content of orthophosphates is feebly correlative with the chlorophyll A content of dam (r=0.171). Any significant distinction hasn’t been observed between the orthophosphates’ mergers of four months’ studying (p=0.05).The strongest value ( 1.3 mg /l) has been checked in the course of the month of September and the weakest value (0.14 mg/l) during the month of November. Meanwhile, the nitrate’s content, temperature and chlorophyll A of waters were strongest in the course of October (respectively, 6.6 mg /l ; 29.14 °C ; 0.4 ug /l) and lowest in December ( respectively, 3 mg/l ; 23.25 °C ; 0.02 ug/l).These results showed that October’s and December’s months are periods that cover the eutrophication’s risk of Ouagadougou’s third dam. It comes out from the results that, water from the dam of good quality from the physicochemical stand point and covers with the statement of trophical mesotrophy’s traces.© 2016 International Formulae Group. All rights reserved.Keywords: Eutrophication, chlorophyll A, trophical statement, nitrate, temperature, Ouagadougou’s 3rd da

Effectiveness of Moringa oleifera defatted cake versus seed in the treatment of unsafe drinking water : case study of surface and well waters in Burkina Faso.

peer reviewedSafe drinking water access for rural populations in developing countries remains a challenge for a sustainable develop-ment, particularly in rural and periurban areas of Burkina Faso. The study aims to investigate the purifying capacity of Moringa oleifera defatted cake as compared to Moringa oleifera seed in the treatment of surface and well waters used for populations alimentation. A total of 90 water samples were collected in sterile glass bottles from 3 dams’ water reservoirs, a river, and a large diameter well, respectively. The water samples were treated in triplicate with Moringa oleifera seed and defatted cake coagulants. At different settling time and coagulant concentration, turbidity and pH were measured to determine the optimal conditions and factors influencing treatment with regard to sampling source. Nine physicochemical parameters (turbidity, pH, nitrates, nitrites, calcium, magnesium, total hardness, organic matter and sulfates), three bacterial fecal pollution indicators (Escherichia coli, fecal Coliforms and fecal Streptococcus) and parasite cysts were monitored based on laboratory standard methods. Data were analyzed using the Student’ t test and XLSTAT 7.5.2 statistical software. From the results obtained, for the same concentration of coagulant, settling times providing the lowest turbidity were significantly shorter (p<0.0001) with Moringa oleifera cake than seed. Optimum settling time with Moringa oleifera cake was between 15-60 min versus 60-120 min, with Moringa oleifera seed. Both treatments reduced significantly minerals concentration in water excepted sulfates for which the concentration reversely increased. However, only Moringa oleifera cake treatment reduced organic matter content in all the water samples, while it increased with Moringa oleifera seed one (p<0.0001). The reduction of microbial pollution indicators was 92-100% with M. oleifera cake treatment and 84-100% with M. oleifera seed one. Overall, for all water samples, Moringa oleifera cake treatment appeared more efficient in improving drinking water quality than the M. oleifera seed treatment

Problematic of drinking water access in rural area : case study of the Sourou Valley in Burkina Faso

peer reviewedSafe drinking water access for rural populations in developing countries remains a challenge for a sustainable develop-ment. The study aims to investigate the drinking water quality and the factors affecting this quality in the Sourou valley in Burkina Faso. A total of 135 water samples were collected in sterile glass bottles during the dry seasons 2007, 2008, and 2012 from 10 drillings and 5 wells. Fifteen physicochemical parameters and two fecal pollution indicators (Es-cherichia coli and fecal Coliforms) were monitored based on laboratory standard methods. Datas were analyzed, using the Student t’ test and XLSTAT 7.5.2 statistical software. From results obtained, water quality was related to water source and sampling period as well (p < 0.0001). 30% of drillings provided water with nitrates concentration over the World Health Organization (WHO) guideline value. High turbidity was also observed for some drillings. Moreover, 90% of drillings showed water total hardness largely over the WHO threshold value. Water from drillings were exempt of fecal pollution, contrasting with the wells one which appeared uniformly polluted with concentrations exceeding sometimes 103 and 104 CFU/100 ml for E. coli and fecal Coliforms, respectively. Field investigations showed a prefer-ence of wells as drinking water source, and that appeared related to the lack of self-management of drillings and to cul-tural considerations. Overall, this study highlighted that a regular survey of water quality, management of protection zones around drinking water sources, sensitization on water resources self-management, hygiene and health issues, and providing appropriate household disinfection methods could help advancing to reach an effective safe drinking water access for rural populations in the country

Réponses Physiologiques et Biochimiques au Déficit Hydrique Du Soja (Glycine Max (L.) Merrill) Inoculé par Bradyrhizobium Japonicum

RésuméUne étude de l’effet d’un déficit hydrique par interruption d’arrosage d’eau sur les paramètres physiologiques et biochimiques d’une variété de soja (Glycine max (L.) Merrill) inoculée par la bactérie du sol Bradyrhizobium japonicum, a été réalisée. Les résultats obtenus montrent que le déficit hydrique entraine aux stades végétatif et de floraison, une baisse de la teneur relative en eau, des potentiels hydriques foliaires de base et minimal et une élévation des teneurs en proline, en sucres solubles et en protéines totales foliaires. Les teneurs en chlorophylles a, b et totales ont eu une élévation significative au stade végétatif, sous l’effet du déficit hydrique. L’inoculation a augmenté significativement le potentiel hydrique minimal chez les plantes stressées au stade floraison, ainsi que le nombre de gousses et de graines aux deux stades chez les témoins. De plus, elle a atténué l’accumulation de proline et de sucres solubles chez les plantes stressées au stade végétatif. Par contre, l’inoculation a amélioré l‘accumulation de proline et de sucres solubles au stade floraison. Cette étude a  montré que le soja tolère mieux le stress hydrique aux niveaux physiologique et biochimique, lorsqu’il est préalablement inoculé avec Brayrhizobium japonicum

On the Slovene novel after 1990

peer reviewedWater purification with Moringa oleifera seeds has received a lot of attention because it reduces water turbidity and pathogenic microorganisms. However, it is important to define the optimum conditions of storage to preserve the treated water quality. The study aims to investigate microbial quality of water treated with Moringa oleifera seeds or cake coagulants inrelation to the storage temperature and shelf life in order to define the optimum conditions of storage. A total of 45 water samples from 3 water reservoirs of Loumbila, Ziga and Ouaga 3 dams were collected in sterile glass bottles and treated in triplicate with Moringa oleifera seeds or defatted cakes coagulants. Treated water samples obtained at optimum conditions were stored at room temperature (25°C - 30°C) and at 4°C. Fecal bacteria pollution indicators (Escherichia coli, fecal coliforms and fecal streptococcus) and parasites were monitored every 24 hours during three (3) days abased on laboratory standard methods. Data were analyzed using the Student's t-test and XLSTAT 7.5.2 statiscal software. From the results obtained, bacterial indicators increased significantly with storage temperature (p < 0.0001) and shelf life (p < 0.0001). However, for all water samples bacterial growth was more important in samples treated with Moringa oleifera cakes than seeds (p < 0.0001). For water samples treated with Moringa oleifera seeds and stored at room temperature, bacterial increase after 72 hours was 57 - 80, 42 - 50 and 22 - 47 CFU/100 ml for fecal coliforms, E. coli and fecal streptococcus, respectively. With Moringa oleifera cake's treatment, the increase was 63 - 104, 57 - 82 and 28 - 52 for the same indicators, respectively. Bacterial growth was also more important at room temperature than at 4°C. Thus, microbiological quality of water treated with Moringa oleifera seeds was better than cakes whatever storage temperature and shelf life. Overall, water treated with Moringa oleifera seeds should be stored at low temperature and consumed within 24 hours