Etude de l’activité antihypertensive d’une association de plantes (Schrankia leptocarpa, Garcinia kola et Ocimum americanum) chez le rat Wistar

En pharmacopée traditionnelle, le traitement de l’hypertension artérielle (HTA) fait souvent appel à des associations de plantes. L’objectif de cette étude est d’évaluer in vitro et in vivo, l’effet anti-hypertensif de l’association Schrankia leptocarpa, Garcinia kola et Ocimum americanum. L’analyse phytochimique puis l’évaluation de la toxicité ont été réalisées respectivement par la technique de caractérisation en tube, sur les larves de crevette Artemia salina et des rats de souche Wistar. L’effet de l’extrait aqueux de cette association de plantes a été apprécié sur des rats Wistar rendus hypertendus par l’administration de L-Name (N(ω)-Nitro- L-Arginine-Méthyl Ester) à la dose de 20 mg/kg de poids corporel. Un traitement d’une semaine à cet extrait aqueux à dose minimale (250 mg/kg de poids corporel), a entraîné une baisse de la pression artérielle (PA) moyenne (135,8 ± 12,1 mm Hg), proche de la normale (132,3 ± 5,5 mm Hg). A la dose maximale de 500 mg/kg de poids corporel, la PA passe en dessous de la normale (116,6 ± 52,6 mm Hg), sans toutefois qu’il y ait une différence significative entre les deux doses (p > 0,05). Les molécules des groupes chimiques présents dans l’extrait aqueux interviendraient donc dans la régulation des paramètres cardiovasculaires. L’association de plantes étudiée a un effet positif sur l’HTA induite et les résultats semblent indiquer son innocuité.Mots clés : Pression artérielle, plantes médicinales, hypotenseur, toxicité

Effect of pineapple (Ananas comosus) on haematological and biochemical parameters in albinos Wistar rats intoxicated with Doliprane

The aim of this study is to evaluate the liver’s protection of Ananas comosus on albinos Wistar rats intoxicated with Doliprane® which contained 20% of paracetamol. Four batches of 30 were used. The negative control group was not treated with Doliprane® and A. comosus. Batches no. 2 and no. 3 were treated for six weeks with Doliprane® (2 g per kg of body weight for each day). Each rat of batch 2, has received by cramming, 0.06 ml/kg of body weight for each day of the stalk against 0.12 ml per kg of body weight for each day for batch no. 3. The batch no. 4 has been addicted to Doliprane® (2 g / kg of body weight for each day) and was not treated with A. comosus. A haematological study plus determination of the serum level of glucose, triglycerides and cholesterol was carried out. Doliprane® induced a hypochromic anemia in the rats of batch 4. This anemia has been corrected with the stalk of A. comosus in the rats of batches no. 2 and no. 3. The serum level of glucose and triglycerides increased in the rats of batch no. 4 (p < 0.0001), but that of cholesterol decreased (p < 0.0001). The stalk of A. comosus protects the liver against haematological and biochemical aberrations induced by Doliprane®.Key words: Ananas comosus (pineapple), hepato-protection, Doliprane®, toxicity

Etude de la qualité bactériologique des aliments vendus sur le campus de l’Université d’Abomey Calavi au Bénin

Selon l'Organisation Mondiale de la Santé, deux millions de personnes dans les pays en développement décèdent chaque année, à cause des intoxications alimentaires contractées en partie dans la restauration de masse. Le double objectif de cette étude était d’analyser la qualité bactériologique des aliments vendus en restauration rapide sur le campus universitaire et de déterminer la fréquence des bactéries multi résistantes (BMR) isolées. En six mois; 390 échantillons d’aliments ont été collectés et analysés. Escherichia coli, Salmonella, Staphylococcus aureus et Enterococcus ont été recherchées. Les bactéries ont été dénombrées puis identifiées suivant les méthodes biochimiques classiques. Un antibiogramme a été réalisé sur les souches isolées. Le sérotype Escherichia coli O157 et les souches d’Escherichia coli productrices de bêta lactamase à spectre élargi (ECBLSE) ont été recherchés. 74% des prélèvements sont contaminés; 325 souches des bactéries recherchées sont isolées, dont 116 (36%) constituent des BMR parmi lesquelles 44% de ECBLSE, 32% de Staphylococcus aureus résistante à la méticilline et 24% d’Entérocoque résistant à la vancomycine. Deux souches de Salmonella enteritidis et 21 souches d’Escherichia coli O157 ont été détectées. Il ressort de ces résultats que la qualité bactériologique des aliments analysés n’est pas satisfaisante; la proportion de BMR est élevée, et la transmission aux consommateurs est possible.© 2010 International Formulae Group. All rights reserved.Mots clés: Toxi-infection alimentaire; BMR, campus universitaire, Béni

Toxins and adhesion factors associated with Staphylococcus aureus strains isolated from diarrhoeal patients in Benin

Staphylococcus aureus is a causative agent of acute and infectious diarrhoea. In Africa, there is no sufficient information on the virulence and the degree of factors produced by its diarrhoea-isolated strains. Clinical features and virulence factors produced by S. aureus isolated from diarrhoeal-patients admitted at the Hospital Hubert Koutoukou Maga (HKM) in Cotonou was investigated. The virulence factors were screened by radial immunoprecipitation and multiplex polymerase chain reaction (PCR).Fifteen antibiotics were tested. Among independent 115 patients examined for diarrhoea, 32 had faeces positive for S. aureus isolated as pure culture. Most of these patients were hospitalized (21/32) and developed aqueous, bloody and painful diarrhoea, after antimicrobial therapy. About 62% were resistant to oxacillin. Genes encoding for clumping factor B and for laminin binding protein were detected in 62% of S. aureus isolates. About 94% of LukE-LukD producing strains have been isolated from patientsdeveloping post-antibiotic associated diarrhoea (PAAD). The Panton-Valentine Leucocidin (PVL) was produced by 19% of isolates, all from PAAD. This study points out new data concerning virulencefactors and adhesion factor produced by S. aureus strains isolated from diarrhoea in Benin. The culture of the faeces will not always allow the diagnosis. It is important to update a technique, which enablesresearchers to carry out the virulence factors produced by these bacteria

Possibilities of sweet potato [Ipomoea batatas (L.) Lam] value chain upgrading as revealed by physico-chemical composition of ten elites landraces of Benin

Sweet potato is one of the most important food security promoted root crops in the world, especially in sub-Saharan Africa. Unfortunately, the crop is still neglected and underutilized in Benin Republic. To establish baseline data for its better utilization for upgrading its value chain, 10 selected local varieties (01 cream, 02 white, 03 yellow, and 04 orange flesh-colored) were compared for their macro-nutritional composition assessed using standard Association of Official Analytical Chemists (AOAC) procedures and spectrophotometry methods. The results indicate that sweet potato dry matter, protein, fiber, and ash content ranged from 46.11 to 25.9%, 4.09 to 1.97%, 1.81 to 3.00%, and 4.70 to 2.56%, respectively and orange flesh cultivars were found very rich. Pearson correlation analysis of variables revealed that dry mater content is positively correlated with carbohydrate and energy values, but negatively correlated with ash and fiber content, while starch content is strongly correlated with fiber content. Principal component analysis allowed us to classify the sweet potato varieties into 03 varietal groups among which Group 2 (05 varieties) exhibited rich fiber, ash, and protein contents and may be recommended for infant foods formulations. These results constitute important orientation for sweet potato processing chain organization in Benin and for the establishment of future nutrition and breeding programme.Key words: Benin, sweet potato, Ipomoea batatas, nutritional composition, orange flesh cultivar, value chain

Proximate, mineral and vitamin C composition of vegetable Gbolo [Crassocephalum rubens (Juss. ex Jacq.) S. Moore and C. crepidioides (Benth.) S. Moore] in Benin

Gbolo (Crassocephalum crepidioides and Crassocephalum rubens) is a traditional leafy vegetable highly consumed in southern and central Benin, as well as in some part of northern Benin. The nutritional potential of the two species of Gbolo were evaluated through their proximate composition, mineral and vitamin C profile using recommended AOAC method of analysis. The analysis revealed that the contents in raw protein, total lipids, ash and carbohydrates expressed in % of dry matter were  27.13±0.01%,3.45± 0.00%,19.02± 0.01%and 42.22 ± 0.04% for C. crepidioides; 26.43± 0.01%, 2.75± 0.01%, 19.76± 0.05% and 43.11±0.10 % for C. rubens respectively. The content of vitamin C for 100g of fresh leaf is of 9.17 mg for C. crepidioides and 3.60 mg for C. rubens. The moisture content (% of cool matter) and the total metabolizable energy (kcal/100 g of dried matter) were respectively 86.79± 0.04 %and 308.45 ± 0.28 for C. crepidioides and 87.95% ± 0.07 %and 302.91 ± 0.56 for C. rubens. The result of the mineral composition indicated that the sodium (Na), potassium (K), phosphorus (P), magnesium (Mg), calcium (Ca), iron (Fe), Manganese (Mn) and Copper (Cu) contents were higher in C. rubensthan in C. crepidioides. With regard to the obtained values, the Gbolo vegetable showed a satisfactory composition and a significant variability between the mineral salts in its two species and can be valorised for a balanced nutrition of populations. Efforts should be made for the promotion of its wide cultivation and consumption. © 2013 International Formulae Group. All rights reserved.Keywords: Benin, Crassocephalum, Gbolo, mineral composition, proximate composition, vitamin C

Susceptibility of Spodoptera frugiperda to chemical insecticides and control failure likelihood estimation in Burkina Faso

The fall armyworm, Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) has recently invaded sub-Saharan African countries. It has been causing significant losses to maize, pearl millet, sorghum, rice, and other crops since 2016. Several insecticides have been promoted, but farmers have reported control failures. In this work, we collected seven fall armyworm populations in as many maize-producing areas of Burkina Faso. We used the approved IRAC foliar bioassay protocol to evaluate the susceptibility of third instar larvae to six chemical insecticides commonly used by maize farmers, including different modes of action (active ingredient): acetylcholinesterase inhibitors (methomyl, chlorpyriphos-ethyl), sodium channel modulators (deltamethrin, lambda-cyhalothrin), chloride channel activators (emamectin benzoate, abamectin). Lethal concentrations and control failure likelihood (CFL, using Guedes' 2017 formula) were calculated for each population and active ingredient. For all seven populations of S. frugiperda, LC80 values are significantly higher than the manufacturer's recommended rates and CFL values are high, 66-100% for both pyrethroids (deltamethrin, lambda-cyhalothrin) and abamectin. In contrast, the LC80 values for emamectin benzoate emamectin benzoate (0.001 mg/l), methomyl (43 - 278 mg/l) and chlorpyrifos-ethyl (284 - 659 mg/l) are lower than the recommended rates. Emamectin benzoate, methomyl and chlorpyriphos-ethyl insecticides have a negligible risk of control failure (i.e. their CFL values are below 0%) and are the most efficient for the control of the fall armyworm in Burkina Faso. These active ingredients should be alternated in the control of the pest to delay the development of resistance.PRD AGRO-EC

Susceptibility of fall armyworm Spodoptera frugiperda (JE Smith) to microbial and botanical bioinsecticides and control failure likelihood estimation

peer reviewedDescription of the subject. The fall armyworm Spodoptera frugiperda (JE Smith) has become one of the most devastating pests of maize and other important economic crops in Africa since 2016. Among the alternatives to chemical insecticides, bioinsecticides are an interesting option that needs to be explored. Objectives. The susceptibility of fall armyworm to seven bioinsecticides available on the West African market was evaluated in Burkina Faso. Method. Bioassays were conducted following the approved IRAC 020 protocol. Results. Spinetoram (LC80 = 85.3 µg·l-1) and spinosad (LC80 = 437.9 µg·l-1) were the most toxic at concentrations below those recommended by the manufacturer, and had control failure likelihoods close to 0%. Bacillus thuringiensis and products based on Azadirachta indica and Carapa procera extracts were less effective (at the manufacturers' recommended doses), even though they showed significant levels of toxicity on young instars. Conclusions. A list of effective bioinsecticides should be communicated for sustainable management of fall armyworm in West Africa

What natural enemies are associated with the fall armyworm Spodoptera frugiperda Smith in Burkina Faso?

The fall armyworm Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) has invaded sub-Saharan African countries where it threatens maize production and several other economically important crops. Given the adverse effects of chemical insecticides on human health, the environment and living organisms, biological control is an alternative to control this pest. In this study, we aimed to identify the natural enemies that control this pest in Burkina Faso. Surveys were conducted in nearly 50 maize fields in the provinces of Houet and Kadiogo, in order to collect eggs, larvae and arthropod predators of the pest. For predators, some were observed directly in the field and others verified in the laboratory. Natural enemies were identified using identification keys and databases from GBIF and CABI. About 19 species of natural enemies belonging to the group of parasitoids, entomopathogens and predatory arthropods were identified. Parasitoids included Chelonus bifoveolatus (Szépligeti), Coccygidium luteum (Brullé), Drino sp., and some unidentified species. Entomopathogens included Mermithidae nematodes and an entomopathogenic fungus. Among the predators, Forficulidae [Diaperasticus erythrocephalus (Olivier), Forficula senegalensis (Serville)], Formicidae [Pheidole megacephala (Fabricius) and others], Coccinellidae [Cheilomenes sulphurea (Olivier)], Carabidae (Calleida sp.), Reduviidae (Rhynocoris sp.), Mantidae, Pentatomidae, and some Areneae were encountered. Several natural enemies have expanded their niche by adapting to S. frugiperda as a new host and actions are needed to exploit their potential.PRD AGRO-EC

Prevalence of human papillomavirus infection in women in Benin, West Africa

<p>Abstract</p> <p>Background</p> <p>Cervical cancer ranks as the first most frequent cancer among women in Benin. The major cause of cervical cancer now recognized is persistent infection of Human Papillomavirus (HPV). In Benin there is a lack of screening programs for prevention of cervical cancer and little information exists regarding HPV genotype distribution.</p> <p>Methods</p> <p>Cervical cells from 725 women were examined for the presence of viral DNA by means of a polymerase chain reaction (PCR) multiplex-based assay with the amplification of a fragment of L1 region and of E6/E7 region of the HPV genome, and of abnormal cytology by Papanicolaou method. The association between HPV status and Pap test reports was evaluated. Socio-demographic and reproductive characteristics were also related.</p> <p>Results</p> <p>A total of 18 different HPV types were identified, with a prevalence of 33.2% overall, and 52% and 26.7% among women with and without cervical lesions, respectively. Multiple HPV infections were observed in 40.2% of HPV-infected women. In the HPV-testing group, the odds ratio for the detection of abnormal cytology was 2.98 (95% CI, 1.83-4.84) for HPV positive in comparison to HPV negative women. High risk types were involved in 88% of infections, most notably HPV-59, HPV-35, HPV-16, HPV-18, HPV-58 and HPV-45. In multiple infections of women with cytological abnormalities HPV-45 predominated.</p> <p>Conclusions</p> <p>This study provides the first estimates of the prevalence of HPV and type-specific distribution among women from Benin and demonstrates that the epidemiology of HPV infection in Benin is different from that of other world regions. Specific area vaccinations may be needed to prevent cervical cancer and the other HPV-related diseases.</p