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Aims: Ageratum conyzoides L. is a small annual herbaceous highly odorous plant use in traditional medicine. The aim of this study is to evaluate in vitro antioxidant potential, toxicity and antimicrobial activity of aerial part extracts of A. conyzoides on strains potentially involved in vaginal infections. Methodology: An ethnobotanical survey has been carried out on A. conyzoides among ethnobotanists and traditional therapists in fifteen markets in the communes of Abomey- Calavi, Cotonou, Zogbodomey, Bohicon and Abomey in Southern Benin. The phytochemical screening was a qualitative analysis based on staining and precipitation reactions. Antimicrobial activity of A. conyzoides aqueous and ethanolic extracts was evaluated on reference and clinical strains of Staphylococcus aureus, Candida albicans and Escherichia coli using micro dilutions method in wells from. The toxicity of A. conyzoides extracts was determine using Artemia salina larvae, whereas the antiradical activity was evaluated using the Ferric Reducing Antioxidant Power (FRAP) method. Results: The survey showed that the population of Southern-Benin uses A. conyzoides according to different modes of preparation. Also, the administration in the treatment of a variety of pathologies affecting the female reproductive system. The phytochemical screening revealed the presence of flavonoids, tannins, anthocyanins, triterpenes and C- heterosides. The yield of 6.18% for the aqueous extract and 4.32% for the ethanolic extract as recorded. The highest inhibition diameter (24.05 ± 0.5 mm) was obtained using aqueous extract against the clinical S. aureus strain. In contrast, the lowest inhibition diameter (10±0 mm) was obtained against the S. aureus ATCC29213 with the same extract. The Minimum Inhibitory Concentration varied from 2.5 to 5 mg/ml. Both extracts show a bactericidal and fungicidal effect on the different strains studied but the sensitivity of the strains to the aqueous extract is better compared to the ethanolic extract. In addition, the aqueous extracts showed higher antioxidant power compared to the ethanolic extract. No toxicity is revealed for both extracts. Conclusion: The results obtained show that the aqueous and ethanolic extracts of the aerial part of A. conyzoides have antioxidant and antimicrobial properties on strains involved in vaginal infections and do not present a toxicity.

Fermentation is an ancestral process and one of the most used economic methods in the preservation and transformation of cereal-based food raw materials. They are essentially rich in carbohydrates, but they can also be a source of micronutrients such as iron and are used in many traditional culinary preparations, in particular fermented porridges. The aim of this study is to identify the variability of fermented cereal-based porridges produced and consumed in northern Benin. Thus, 315 producers and consumers were randomly interviewed in nine localities of northern Benin. First, field surveys were carried out in the traditional areas of porridge production and consumption in the northern region of Benin in order to establish the consumption map of fermented porridges. Secondly, interviews and occasional conversations were used for sample collection as well as occasional interviews (individual survey). During our investigation, eight (koko, bobossou, gbangba, apkan, sagagnega, akloui, bita and fourra) porridge were reported. Corn, millet and sorghum are cereals that are used for proceeding those porridges. The interviewed people are predominantly (35.53%) between 18 and 25 years old of age followed by those aged between 25 and 31 years old (30.82%). Mostly (63.21%) women were interviewed with a sex ratio (M/F = 0.58) and involved in the production of traditional porridge. More than 36% of respondents had at least secondary education, 30.82% are uneducated, 22.64% have primary education and 10.06% had at least university level. A significant association was observed between the cereal used and the type of porridge (p

Lake Nokoué, a major component of the hydrographic system of the Ouémé delta, is the largest lagoon-estuarine ecosystem in Benin. Recent studies have shown that benthic processes would actively participate in the maintenance of eutrophication and biogeochemical cycle of this ecosystem. In order to understand the implication of the bottom on the quality of the waters of the lake, a monthly follow-up of ten (10) parameters of quality of the waters of the bottom was undertaken from July 2020 to December 2021 on a network of nineteen (19) stations distributed on the whole lake. Univariate and multivariate analysis techniques were used to assess the spatial and temporal dynamics of these waters. The Kruskal-Walis test, PCA, correlation analysis and discriminant analysis all showed a very marked influence of the hydrological regime on the concentration of nutrients compared to the influence of anthropogenic activities around the lake and an influence of climatic conditions on internal processes. Indeed, les water inflows from the Ouémé watershed are the main contributors of phosphorus in the lake while benthic processes are the most important contributors of nitrogen. Cluster analysis defined three significantly different areas in Lake Nokoué: the channel, the center of the lake and the river mouth. A single station in each cluster could be used for a spatial assessment of water quality over the entire lake.

Staphylococci can cause urinary tract infections (UTIs). These UTIs are among the significant causes of antibiotic resistance and the spread of antibiotic-resistant diseases. The current study is aimed at establishing a resistance profile and determining the pathogenicity of Staphylococcus strains isolated from UTI samples collected in Benin. For this purpose, urine samples (one hundred and seventy) that were collected from clinics and hospitals showed UTI in patients admitted/visited in Benin. The biochemical assay method was used to identify Staphylococcus spp., and the disk diffusion method tested the antimicrobial susceptibility. The biofilm formation ability of the isolates of Staphylococcus spp. was investigated by the colorimetric method. The presence of mecA, edinB, edinC, cna, bbp, and ebp genes was examined by multiplex polymerase chain reaction (PCR). The results showed that Staphylococcus species were identified in 15.29% of all infected individuals and that 58% of these strains formed biofilms. Most Staphylococcus strains (80.76%) were isolated in female samples, and the age group below 30 years appeared to be the most affected, with a rate of 50%. All Staphylococcus strains isolated were 100% resistant to penicillin and oxacillin. The lowest resistance rates were seen with ciprofloxacin (30.8%), gentamicin, and amikacin (26.90%). Amikacin was the best antibiotic against Staphylococcus strains isolated from UTIs. The isolates carried mecA (42.31%), bbp (19.23%), and ebp (26.92%) genes in varying proportions. This study provides new information on the risks posed to the population by the overuse of antibiotics. In addition, it will play an essential role in restoring people’s public health and controlling the spread of antibiotic resistance in urinary tract infections in Benin.

Background:Vibrio infections have increased in Benin, and this phenomenon is expected to increase due to climate change, increased consumption of contaminated water and the number of people who are immunocompromised. The aim of the work: The objective of this study was to evaluate the risk of Vibrio transmission linked to the use of contaminated water in Benin. Methodology: Water samples [n = 220] were analyzed to isolate Vibrio strains using their biochemical and cultural characteristics. The species were identified by the Polymerase Chain Reaction technique by monitoring the search for genes encoding the cholera toxin of Vibrio cholerae [ctxA and ctxB] and the direct thermostable and thermostable hemolysins linked to Vibrio parahaemolyticus [tdh and trh]. Results: Among the 220 collected samples, the biochemical tests revealed 86 strains of Vibrio species; Vibrio cholerae [35%], Vibrio parahaemolyticus [18.60%] and Vibrio alginolyticus [13.95%] were identified using molecular tool. The presence of genes encoding the main virulence factors of the strains studied. Thus 6.67%, 10% and 3.33% of the strains of Vibrio cholerae respectively contain the toxins ctxA, ctxB and the couple ctxA and ctxB. Likewise, the Vibrio parahaemolyticus strains contain 12.5% tdh toxins and 31.25% [tdh and trh]. The search for genes [tdh and trh] in Vibrio alginolyticus was also negative. Conclusion: Epidemics can be triggered by natural or fabricated events that contaminate drinking water or compromise access to safe drinking water and sanitation. The incidence of vibriosis is increasing, perhaps in part because of the spread of Vibrio species promoted by climate change and increasing water temperature.

This work aims at assessing toxin production capability and antibiotic resistance profiles of thermo-tolerant Gram-negative bacilli strains isolated from three types of fermented dairy products (yoghurt, degue millet and degue couscous). Samples collected in Abomey-Calavi and Cotonou were analyzed for microbial, biochemical and molecular parameters. Samples were contaminated with thermo-tolerant Gram-negative bacilli strains at 13.88%. The high contamination rate was recorded with the samples of degue couscous and the lowest contaminated samples were degue millet. Morning samples were more contaminated. Klebsiella pneumoniae, Enterobacter aerogenes, Escherichia coli and Enterobacter cloacae were the most identified bacteria. The most isolated species in the dry season was E. coli. In the rainy season, K. pneumoniae and E. cloacae were the most isolated species. K. pneumoniae was the most formative of biofilm (38.9%). About 12% of the isolated strains were extended-spectrum beta-lactamases (ESBL) producers. The higher resistance rate was observed with amoxicillin and doxycylin (92.3%). Imipenem was the most efficient molecule on the isolated strains with 00% of resistance. The blaTEM gene was detected in 51.43% of the isolated strains followed by blaSHV (37.14%), blaCTX-M (8.57%) and blaOXA-1 (2.86%). It is necessary to train sales people on good hygiene practices for food during their production and their distribution. Key words: Fermented milk products, thermo-tolerant gram-negative bacilli, toxins, antibiotics resistance, Benin.

Morinda citrifolia is a plant with broad nutraceutical and therapeutic effects and used in the traditional treatment of several ailments. The objective of this work is to investigate the phytochemistry of the fruit juice of M. citrifolia on one hand and on other hand to evaluate its antiradical and antibacterial activity. The phytochemical investigation was carried out by tube staining tests of the extract of two types of fruit juice of M. citrifolia. The antioxidant activity of these juices was evaluated by reducing the DPPH radical method. Concerning the antibacterial activity, it was tested on the in vitro growth of 10 reference bacterial strains using the well diffusion method. Qualitative phytochemistry of M. citrifolia fruit juices revealed the presence of large groups of secondary metabolites including polyphenols, reducing compounds, mucilage and terpernoids. The antioxidant activity of M. citrifolia fruit juices is dose-dependent and higher than that of ascorbic acid. Antimicrobial activity on other hand revealed that fruit juices inhibit growth inhibitory activity of Staphylococcus aureus, Pseudomonas aeruginosa, Proteus mirabilis, S. epidermidis, Proteus vulgaris, Streptococcus oralis, Enterococcus faecalis and Escherichia coli. This observed difference is significant for each juices on the strains (p

Healthcare-associated infections (HCAIs) remain a major public health concern. The aim of this study was to characterize potential pathogenic bacteria isolated in high-risk infectious services at the University Hospital Center of Suru-Lere in Benin. A cross-sectional, descriptive study was carried out on 215 samples with 8 air samples, 20 hand samples and 187 samples of medical-technical material. Genes for resistance to β-lactam antibiotics (blaTEM, blaSHV, blaCTX-M and blaOXA-1) were sought. The data were processed and analyzed using EPI Info version 3.5.4 software. A total of 10 bacterial species were identified. Of the 319 bacterial strains identified, Staphylococcus saprophyticus, Staphylococcus aureus and Enterococcus faecalis were predominant at 20.06%, 17.87% and 11.28% respectively. Antibiotic susceptibility showed that the majority of bacterial strains were multidrug-resistant. Of the 4 resistance genes sought, only the blaTEM and blaSHV genes were found. The poor microbiological quality observed in high-risk infectious services could be a risk factor for healthcare-associated infections. It is therefore useful to implement preventive measures in order to prevent or reduce the risk of healthcare-associated infections.

Staphylococcus aureus is a major human pathogen present on a third of the healthy population. The bacterium possesses an extensive arsenal of virulence factors. The pathogenicity is linked with S. aureus high plasticity and its exceptional ability to incorporate foreign genetic material. The aim of the present study was to perform molecular characterization of Staphylococcus aureus strains isolated from the clinical environment of the CHU-Z Abomey-Calavi/Sô-Ava. Isolation of Staphylococcus aureus bacterium was performed on Chapman agar. Toxin production by isolated S. aureus strains was investigated using the radial immunoprecipitation technique. A colorimetric assay was used to evaluate Staphylococcus aureus lipase (SA-Lipase) production. Finally, the expression of antibiotic resistance genes and genes encoding toxins production was investigated. Our data suggest that none of the isolated Staphylococcus aureus strains expressed the investigated toxin genes. Interestingly, SA-Lipase was produced by 14.28% of our isolated S. aureus strains. The mecA gene was present in 57.14% of the isolated strains, while PVL and TSST-1 genes were identified in 2.85 and 7.14% of S. aureus, respectively. Significant genetic diversity was observed along the hospital environment S. aureus strains. The present study reveals the level of virulence of S. aureus strains isolated in the different units of CHU-Z Abomey Calavi/Sô-Ava through the production of lipase, PVL, and epidermolysins. The molecular study has favored a genetic characterization within the isolated strains.

Aims: The aim of our work was, on the one hand, to evaluate the risk factors for infectious contamination in hospital environments and, on the other hand, to carry out a microbiological control of surfaces at the Abomey-Calavi / So-Ava hospital in Benin. Methodology: The risk factors were evaluated using structured interviews based on the questionnaire. Fifty-five health care workers were surveyed and the questionnaire focused on: i) knowledge of care-associated infections and risk factors, ii) services most affected by care-associated infections and iii) origin of care-associated infections. For the microbial quality control of medical surfaces and materials, samples were collected by the dry swab method and the microbial isolation was carried out on Chapman and EMB agar plates. The biochemical analyses were carried out for the confirmations. Results: Out of 55 respondents, the 93% think that bacterial germs are often involved in care-associated infections. In addition, 80% of respondents believe that the healthcare environment may be the source of care-associated infections. Regarding the microbiological quality of the surfaces, out of 96 samples collected, 77% were contaminated with Staphylococcus spp and 30% with Enterobacteria. Concerning units’ contamination, the highest prevalence was observed in paediatrics with 92% of samples contaminated with Staphylococcus spp followed by the operating theatre (87%). Conclusion: It is clear from our work that hygiene managers must carry out preventive and corrective actions for the respect of the principles of hygiene. It would also be important to conduct regular microbiological monitoring of surfaces to identify any contamination.

International audience; Leptospirosis is a waterborne zoonosis (60,000 infections and 1 million deaths annually). Knowledge about the disease in the urban context is surprisingly rare, especially in Africa. Here, we provide the first study of leptospires in waters within an African city. A simple centrifugation-based method was developed to screen waterborne leptospires from remote or poorly areas. Major ions, trace elements, stable isotopes and pathogenic Leptospira were then seasonally investigated in 193 water samples from three neighborhoods of Cotonou (Benin) with different socio-environmental and hydrographic characteristics. Firstly, no leptospire was detected in tap waters. Secondly, although surface contamination cannot be excluded, one groundwater well was found leptospire positive. Thirdly, pathogenic Leptospira mainly contaminated surface waters of temporary and permanent ponds (9.5% and 27.3% of total prevalence, respectively). Isotopic signatures suggest that leptospires occurred in pond waters formed at the beginning of the rainy season following low to moderate rainfall events. Nevertheless, Leptospira-containing waters possess physico-chemical characteristics that are similar to the spectrum of waters sampled throughout the three sites, thus suggesting that Cotonou waters are widely compatible with Leptospira survival. The frequent contact with water exposes Cotonou inhabitants to the risk of leptospirosis which deserves more attention from public health authorities.

International audience; Highlights• Predominant drivers of the unregulated shallow aquifer degradation in Cotonou were analysed using major ions, Cl/Br molar ratios and stables isotopes as environmental tracers. Vulnerability of this unofficial groundwater resource is due to either salinization or sewage leakage, which is temporally and spatially variable.• Increasing risks from sewage and septic tank leakage during the wet season in neighbourhoods located in discharge areas compared with increasing risk during the dry season in the recharge area.• Mixing with pond water and saline Lake Nokoué water highlight increased risks of shallow groundwater salinization during the dry and small wet seasons in discharge areas.AbstractIn Cotonou, as in many expanding West African cities, major population growth and infrastructural development has not kept up with informal settlement development onto floodable plains and marshes. The population of the slum, which makes up about 60% of the city's inhabitants, is highly disadvantaged and vulnerable to rising sea levels, flooding, sanitation and waste management issues. However, the risks associated with the use of contaminated shallow groundwater for domestic purposes are less recognised. Our study demonstrates that, in many instances, the cheaper option of the use of shallow groundwater from the coastal Quaternary aquifer for domestic purposes represents a significant risk for the poorer residents of Cotonou through the voluntary (drinking) or non-volontary (dish washing, cooking) consumption of this unmonitored and untreated water resource. In the 3 neighbourhoods surveyed, environmental tracers (major ions, Cl/Br molar ratios and stables isotopes) showed that this shallow aquifer is degraded by seawater intrusion as well as septic and sewerage contamination. In particular, the higher NOx concentrations correspond to ranges associated with sewerage and septic tank effluent pollution and the major ion concentrations and delta H-2-delta O-18 signatures showed that high salinity values are where groundwater mixes with saline Lake Nokoue water. The population using this resource from local wells should be made aware of seasonal changes in groundwater contamination and potential health risks associated with sewerage and septic tank contamination.

In the area of study, 4718 gravity data have been processed. Distribution of the resulting anomalies confirms the continuity towards the south of the three characteristic gravity domains already identified north of the parallel 9 °N. Positive anomaly belts underline the presence of magmatic rocks in the foreland of the chain. The tectonic overload characterizing its external zone is mirrored by a very strong overcompensation. A main gradient zone (the regional gradient) is superimposed on a suture zone of allochtonous basic massifs. The internal zone is characterized by a very important undercompensation connected with heavy deep structures. Numerous gravity discontinuities line the three previous sets (foreland, external and internal zones), revealing the great structural complexity of the region. Nevertheless this complexity is frequently concealed or attenuated by smoothing and offset phenomena which are expressed through more regular anomalies and profiles. The present study strengthens the hypothesis of a continental collision chain for the Dahomeyides and emphasizes the hypotheses of micro-continent aggregation together with a progressive rise of the southern part of the studied sector during the Pan-African tectogenesis.

L'objet initial de cette thèse devait être essentiellement la cartographie et l ' étude pétrographique des granites de la bordure Ouest du bassin houiller de St- Etienne. Toutefois, au fur et à mesure de l'avancement de nos recherches , celles- ci se sont de plus en plus orientées vers l 'étude du comportement de quelques éléments majeurs et en traces au cours des diverses phases de granitisation et de migmatisation qui ont caractérisé l'histoire géologique de notre région ., pas de résumé