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 < 0.001). These results support the use of M. citrifolia in traditional medicine and are the starting points for the development of a new drug to combat both dietary conditions and chronic conditions associated with oxidative stress.

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 this study is to evaluate the antimicrobial activity of the R. brasiliensis aerial part extracts collected in southern-Benin. Methodology: The phytochemical screening was performed by a differential precipitation staining method. Aqueous and ethanolic extracts were made using conventional method with water and ethanol as solvent. The obtained extracts were used to evaluate their antimicrobial activity on Staphylococcus aureus strains isolated from skin infections and ten reference strains by the solid-medium diffusion method. The minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined by the liquid macro-dilution method. The cytotoxic effect of the extracts was evaluated on Artemia salina larvae obtained by hatching. Results: The phytochemical screening showed a strong presence of tannins, flavonoids, terpenes, steroids and a medium presence of alkaloids, anthocyanins and mucilage’s. The extraction yields vary according to the solvent: water (15.5%) and ethanol (10.30%). The two extracts variously (p<0.001) inhibited the growth of Staphylococcus aureus strains isolated from skin infections and four reference strains (Staphylococcus aureus ATCC29213, Pseudomonas aeruginosa ATCC27853, Proteus mirabilis A24974, Escherichia coli ATCC25922). However, there is no difference (p > 0.05) in inhibition of strains growth between 24h and 48h. The largest diameter (21±0.75 mm) of inhibition with the reference strains was obtained with P. aeruginosa by action of the aqueous extract. Regarding Staphylococcus aureus strains isolated from skin infections, the largest diameter of inhibition is about 19.25±2.75 mm obtained with strains isolated from ulcers. The average mics of 2.81 mg/ml and 2.08 mg/ml were obtained respectively for the aqueous and ethanolic extracts in the presence of the reference strains. The LC50 determination obtained using the regression line is 0.36 mg/ml for the aqueous extract and 1.16 mg/ml for the ethanolic extract. Conclusion: The aqueous extract is more effective because of its action spectrum. This extract can be used for the development of a soap or ointment to fight against skin infections.

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Escherichia coli is a commensal bacterium and one of the first bacteria to colonize the digestive tract of newborns after birth. It is characterized by great versatility and metabolic flexibility that allows its survival in different niches. The present study aims at analyzing the diversity of E. coli strains isolated from the intestinal microbiota of children aged from 0 to 5 years in the commune of Abomey-Calavi in Benin. For this purpose, a descriptive and analytical cross-sectional study was conducted. A total of 135 stool samples were collected from the pediatric clinic of Abomey-Calavi. Microbiological analyses were performed according to standard microbiology analytical techniques. The molecular characterization of E. coli was performed by investigating eight genes (dinB, icdA, pabB, polB, putP, trpA, trpB, and uidA) using the PCR technique. The results showed that the average loading rate on stool samples was 3.74 × 107 CFU/g for TAMF. A total of 7 species of bacteria were identified at different proportions: Staphylococcus spp (55.36%), E. coli (14.29%), Klebsiella ornithinolytica (12.5%), Serratia odorifera (5.36%), and Enterobacter aerogenes (5.36%). Interestingly, isolated E. coli presented a resistance of 100% to cefotaxime and aztreonam. In addition, resistances of 95.24% and 50% were observed against erythromycin and nalidixic acid, respectively. The molecular characterization of the isolated E. coli strains allowed us to discover another molecular variation within the isolated strains. Genes encoding the enzymes isocitrate dehydrogenase (icd) and DNA polymerase II (polB) were detected at 96.30% in the isolated E. coli strains. Moreover, the genes encoding the enzymes beta-D-glucuronidase (uidA) and DNA polymerase (dinB) were detected at 88.89% in the isolated E. coli strains. Interestingly, 81.48%, 85.19, 92.59%, and 100% of isolated E. coli strains expressed the genes encoding the enzymes tryptophan synthase subunit A (trpA), proline permease (putP), p-aminobenzoate synthase, and tryptophan synthase subunit B (trpB), respectively. The diversity of E. coli strains reflects the importance of regulatory mechanisms in the adaptation of bacteria to the gut microbiota.

Enterobacteriaceae represent one of the main families of Gram-negative bacilli responsible for serious urinary tract infections (UTIs). The present study aimed to define the resistance profile and the virulence of Enterobacteriaceae strains isolated in urinary tract infections in Benin. A total of 390 urine samples were collected from patients with UTIs, and Enterobacteriaceae strains were isolated according to standard microbiology methods. The API 20E gallery was used for biochemical identification. All the isolated strains were subjected to antimicrobial susceptibility testing using the disc diffusion method. Extended-spectrum beta-lactamase (ESBL) production was investigated using a double-disc synergy test (DDST), and biofilm production was quantified using the microplate method. Multiplex PCR was used to detect uro-virulence genes, namely: PapG, IronB, Sfa, iucD, Hly, FocG, Sat, FyuA and Cnf, using commercially designed primers. More than 26% (103/390) of our samples were contaminated by Enterobacteriaceae strains at different levels. Thus, E. coli (31.07%, 32/103), Serratia marcescens (11.65%, 12/103), Klebsiella ornithinolytica (8.74%, 9/103), Serratia fonticola (7.77%, 8/103) and Enterobacter cloacae (6.80%, 7/103) were identified. Among the isolated strains, 39.81% (41/103) were biofilm-forming, while 5.83% (6/103) were ESBL-producing. Isolates were most resistant to erythromycin, cefixime, ceftriaxone and ampicillin (≥90%) followed by ciprofloxacin, gentamycin, doxycycline and levofloxacin (≥50%), and least resistant to imipenem (27.18%). In regard to virulence genes, Sfa was the most detected (28.15%), followed by IronB (22.23%), iucD (21.36%), Cnf (15.53%), PapG (9.71%), FocG (8.74%), Sat (6.79%), FyuA (5.82%) and Hyl (2.91%). These data may help improve the diagnosis of uropathogenic strains of Enterobacteriaceae, but also in designing effective strategies and measures for the prevention and management of severe, recurrent, or complicated urinary tract infections in Benin.

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.

Cholera is re-emerging as an infectious disease with an increase in its overall incidence in Africa since 2008. To analyze the epidemiological aspects of the cholera outbreak in endemic areas in Benin, the study is a retrospective investigation on 2560 data of cholera patients received in health facilities from 2012 to 2016 in Benin. Besides, a prospective study was conducted. This prospective study includes 513 person (health professionals, community workers and people exposed to cholera) of five different areas of the country. It was conducted from April 10 to May 10, 2017. A survey was conducted over 513 in order to collect data on cholera symptoms, hygiene guidelines suggested by the respondents, excreta disposal, drinking water, household waste management and direct observation. Software R 3.4.0 was used for simple correspondence factor analysis (CFA). From 2012 to 2016, 16.48% of samples were taken and 48.34% were positive for Vibrio cholerae O1, El Tor biotype, Ogawa serotypes. The Littoral area is leading in the number of cases (33.83%) followed by Atlantic (23.75%), Ouémé (16.79%) and Colline (8.91%). The survey revealed that the exposed populations are unaware of the symptoms of cholera and do not perceive the quality of drinking water as a strong guidance in the prevention of cholera. Nevertheless, the majority of respondents (86%) are aware for the best times to wash their hands and know that they need to go to hospital in case of symptoms. Our study highlights the persistence of vulnerability factors to cholera in the targeted population, despite a good knowledge of prevention rules among staff and the population.