Essai d’isolement de Campylobacter dans la viande de volaille en République du Bénin

La viande de volaille importée occupe une place importante dans l’alimentation béninoise. Elle est le plus souvent mise en cause dans les cas de toxi-infections alimentaires. De ce fait, elle devrait être sujette à uncontrôle de tous les microorganismes de toxi-infections afin de préserver la santé des consommateurs. Mais il s’avère que Campylobacter, qui de plus en plus est indexé, ne fait pas partie de la gamme des bactériesrecherchées pour la qualification sanitaire des aliments au Bénin. Cette situation serait due aux probables difficultés liées à l’isolement de ce germe. La présente étude a essayé d’isoler par culture cette bactérie afin de prouver que sa recherche en microbiologie alimentaire est possible. Cela pourrait permettre de commencer par l’inclure dans les diagnostics ultérieurs. Pour ce faire, 30 échantillons de viande de volaille importée ont fait l’objet d’analyse au Laboratoire de Microbiologie du Ministère de la Santé. Sur les 30 échantillons, Campylobacter a été isolé dans 6, soit un taux de contamination de 20%. En somme, Campylobacter peut être isolé par culture dans notre contexte.Mots clés : Campylobacter, viande de volaille, maladies alimentaires, Bénin.

Prévalence et rôle des lipides dans l’avènement de l’obésité au Bénin

Le recueil des mesures anthropométriques des étudiants de l’Institut National Médico-Social (INMES) au Bénin nous a permis de calculer l’Indice de Masse Corporelle de cette population, seul indicateur pour évaluer l’état nutritionnel des adultes de point de vue énergétique. Au terme de cette évaluation, il ressort que la prévalence de l’obésité est plus élevée chez les femmes (9,81%) que chez les hommes (0,8%). L’indice de Masse Corporelle (IMC) médian est estimé à 23,03 chez les femmes contre 21,45 chez les hommes. Pour savoir les causes éventuelles de l’obésité, nous avons prélevé le sang de 41 étudiants supposés obèses et 92 ensurpoids et avons dosé les paramètres biologiques comme Cholestérol Total, Cholestérol-HDL, Cholestérol-LDL et Triglycérides. Il ressort de cette étude que, sur les quatre (04) composants lipidiques dosés, seul letaux de cholestérol-LDL est élevé au sein de cette population avec une valeur médiane de 1,52 g/l. Aussi, nous constatons une disparité dans les paramètres dosés. Par ailleurs, presque le quart (25%) des individus ensurpoids ou obèses ont une lipidémie normale. D’après nos résultats, c’est le métabolisme de Cholestérol-LDL qui est perturbé et que l’état d’obésité serait lié à d’autres facteurs tels que génétiques, hormonaux et autres

Antifungal efficiency of plants aqueous extracts with potential for control of Cercospora oryzae miyake in rice

Rice (Oryza spp.) is the third most cultivated cereal crop in Benin, and major staple in the population’s daily diets. Its production, though is heavily impaired by fungal diseases, of which cercosporios accounts for about 60% yield loss. The objective of this study was to examine the efficacy of plant aqueous extracts for control of Cercospora oryzae diseases for improved rice production in Benin. We assessed the in vitro effectiveness of plant extracts on the sporulation and mycelial growth of C. oryzae, by evaluating the effectiveness of extracts on the foliar and panicular incidence, as well as the epidemic of C. oryzae in the field. A randomised complete block design arranged in split plots, was laid out with three spraying replications. The study combined phytiatric tools. Extracts from Lippia multiflora, Azadirachta indica and Eucalyptus camaldulensis at concentrations of 10 and 15% showed antifungal efficacy on Cercospora oryzae in vitro and in the field. Extracts of Cymbopogon citratus and Citrus limon did not exhibit antifungal efficacy against Cercospora oryzae

Diversité Variétale, Qualité Et Utilisation Du Maïs (Zea Mays) En Afrique De l’Ouest : Revue Critique

Maize (Zea mays) is a cereal cultivated through all the region of the world. Its constitutes one of the cereals the most used for human consumption. The current review focused on the diversity, the nutritional quality and the forms of use of maize in West Africa region. The review allowed to notice that more than twenty varieties of maize were cultivated in Bénin and in the sub-region. With regard to nutritional aspect, those different varieties of maize contained variable amounts of starch (64-78%), fat (4- 6%), protein (7-12%), crude fibers (2-2.5%), ash (1-1.5%) and sugar (1-3%). Potassium (324.8-344 mg /100g), magnesium (107.9-115 mg/100g) and phosphorus (99,6-276 mg/100g) were the main mineral in maize. Likewise, leucine, isoleucine, tryptophane and valine all contained in the germ were the main amino acids in maize. These chemical components can be alone or in a possible synergy of action responsible for numerous technological advantages of maize. Through its chemical and technological characteristics the maize constitutes an important raw material for many culinary recipes in West Africa region. So it is important to make the inventory of the main varieties cultivated in the sub-region, to compare them at both nutritional and technological aspects for prospective actions to undertake in order to improve the yield of these varieties and to guarantee food security for the populations

Morphometric characterization of parasite Varroa sp. of bee Apis Mellifera L. in Benin

Open Access JournalVarroa sp. is one of the most important pests of world of bees A. mellifera Linnaeus (Hymenoptera: Apidae). The aim of this study is to analyze the morphological variability of Varroa so as to identify the different morphotypes of V. destructor. The study was conducted in 24 localities and 24 municipalities located in three regions (North-East, North-West and the Centre) of Benin. One to two hives were randomly selected per locality for collecting samples. In total 46 Varroa were examined in this study. Analysis of variance components was used to determine the share of the variability of morphological characteristics of V. destructor based on localities and climatic zones. Numerical classification was performed to group the populations of V. destructor based on morphological descriptors. The results show that the variability of morphological descriptors of V. destructor is usually larger at the community level than in climatic zones. In total four morphotypes of V. destructor are distinguished in Benin through the 4 variables used in the study

Evaluation of Cercospora oryzae Miyake under natural pressure conditions.

Objective: This study is a contribution to the knowledge of Cercospora oryzae Miyake, in order to increase yields. It will consist in: i) evaluating the resistance of five varieties of rice, ii) evaluating the effect of Cercospora oryzae Miyake on the leaf and panicle stages and iii) evaluating the yield.Methodology and results: The study will combine phenotypic and agromorphological tools. On the ninety first (91th) day after sowing, a high incidence of leaf Cercosporiosis was recorded on the varieties TS2 (29.74%), FKR34 (27%) and a very low incidence on the variety ORYLUX6 (5, 78%). From tillering to panicle initiation, the rate of progression of the epidemic r2 = 0.879 is significant in TS2. The ORYLUX6 variety is the most capable of slowing the progression of the epidemic. At the panicular level, from the pasty grain stage to the milky grain stage, the incidence has increased for most of the varieties. The ORYLUX6 recorded the highest yield with 4.38 t/ ha.Conclusion and application potential of the results: Cercospora oryzae Miyake causes a drop in yield by reducing the leaf area of thr leaves. Cercospora oryzae Miyake is an important disease of rice in Sud-Benin. These results constiyute a stage of an in-depth research work on the characterization (agronomic and genetic) of Cercospora oryzae Miyake in order to propose methods of control. Objectifs : L’étude a été une contribution à la connaissance de Cercospora oryzae Miyake afin d’accroitre les rendements. Elle a consistée a : i) évaluer la résistance de cinq variétés de riz, ii) évaluer l’effet de Cercospora oryzae Miyake sur les stades foliaires et paniculaires et iii) évaluer le rendement.Méthodologie et résultats : L’étude a combinée des outils phénotypiques et agromorphologiques. Au quatre-vingt onzième jour après semis on a enregistré une forte incidence de la cercosporiose foliaire sur les variétés TS2 (29,74%), FKR34 (27%) et une très faible incidence sur la variété ORYLUX6 (5,78%). Du stade tallage à l’initiation paniculaire le taux de progression de l’épidémie r2=0,879 a été important chez TS2. La variété ORYLUX6 a été la plus apte à freiner la progression de l’épidémie. Du stade grain pâteux au stade grain laiteux l’incidence à augmentée pour la plus part des variétés. ORYLUX6 a enregistré le rendement le plus élève (4,38 t/ha).Conclusion et application potentielle des résultats: Cercospora oryzae Miyake entraine une baisse de rendement en réduisant les surfaces foliaires des feuilles. La cercosporiose est une affection importante du riz au Sud-Bénin. Ces résultats constituent une étape d’un travail de recherche approfondi sur la caractérisation (agronomique et génétique) de Cercospora oryzae Miyake afin de proposer des méthodes de luttes

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

Effets des rhizobactéries PGPR sur le rendement et les teneurs en macroéléments du maïs sur sol ferralitique non dégradé au Sud-Bénin

L’objectif de l’étude est d’évaluer les effets de 15 rhizobactéries promotrices de croissance végétative (PGPR en Anglais) sur le rendement et l’état nutritionnel des plants de maïs sur sol ferralitique non dégradé du Sud-Bénin. Les semences de maïs ont été inoculées avec des concentrations microbiennes d’environ 108 UFC/ml. Les teneurs en azote, en phosphore et en potassium d’échantillons de plants de maïs ont été déterminées. Les valeurs de rendement du maïs ont été soumises à une analyse de la variance à deux facteurs. Les rhizobactéries Pseudomonas fluorescens ont induit le rendement de maïs le plus élevé, dépassant de 41,46% le rendement de maïs obtenu avec l’inoculation de P. putida et de 118,05% le rendement de maïs obtenu au niveau des plants non inoculés. Les rendements de maïs induits par P. putida et Azospirillium lipoferum sont supérieurs respectivement de 54,17% et de 26,39% au rendement obtenu au niveau des plants non inoculés. Les résultats obtenus augurent de la possibilité d’utiliser les rhizobactéries PGPR comme des engrais biologiques pour une production durable de maïs. Au Sud du Bénin, où la pression démographique est forte et la baisse de la fertilité des sols croissante, l’utilisation de méthodes biologiques pour accroître les récoltes est une solution incontournable.Mots clés: Rhyzobactéries, Rendement, Maïs, Sol ferralitique, Béni

Site-Directed Mutagenesis to Assess the Binding Capacity of Class S Protein of Staphylococcus aureus Leucotoxins to the Surface of Polymorphonuclear Cells

Staphylococcal leucotoxins result from the association of class S components and class F component inducing the activation and the permeabilization of the target cells. Like α-toxin, the leucotoxins are pore-forming toxins with more than 70% β-sheet. This was confirmed by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. In addition, threonine 28 of a predicted and conserved β-sheet at the N-terminal extremity of class S proteins composing leucotoxins aligns with histidine 35 of α-toxin, which has a key role in oligomerization of the final pore. Flow cytometry was used to study different aminoacid substitutions of the threonine 28 in order to evaluate its role in the biological activity of these class S proteins. Finally, results show that threonine 28 of the leucotoxin probably plays a role similar to that of histidine 35 of α-toxin. Mutations on this threonin largely influenced the secondary interaction of the class F component and led to inactive toxin

Staphylococcal Panton-Valentine Leucocidin as a Major Virulence Factor Associated to Furuncles

Panton-Valentine Leucocidin (PVL), one of the β-barrel pore-forming staphylococcal leucotoxins, is known to be associated to furuncles and some severe community pneumonia. However, it is still uncertain how many other virulence factors are also associated to furuncles and what the risk factors of furuncles are in immuno-compromised status of patients, especially the HIV (+) patients. In this paper, we use antigen immunoprecipitation and multiplex PCR approach to determine the presence of 19 toxins, 8 adhesion factors and the PFGE profiles associated to furuncles in three independent patient study groups of S. aureus (SA) isolates collected from the Cayenne General Hospital (French Guiana). The patient groups were made of: 16 isolates from HIV (−) patients, 9 from HIV (+) patients suffering from furuncles, and 30 control isolates from patients with diverse secondary infected dermatitis. Our data reveals that the majority (96%) of SA strains isolated from HIV patient-derived furuncles significantly produced PVL (p<10−7), whereas only 10% of SA strains produced this toxin in secondary infected dermatosis. A high prevalence of LukE-LukD-producing isolates (56 to 78%) was recorded in patient groups. Genes encoding clumping factor B, collagen- and laminin-binding proteins (clfB, cna, lbp, respectively) were markedly frequent (30 to 55%), without being associated to a specific group. Pulse field gel electrophoresis evidenced 24 overall pulsotypes, whereas the 25 PVL-producing isolates were distributed into 15 non clonal fingerprints. These pulsotypes were not specific PVL-producing isolates. PVL appears to be the major virulence factor associated to furuncles in Europe and in South America regardless of the immune status of the HIV patients