Phytochimie des Extraits de Sida acuta et Evaluation de la Toxicite de l’Extrait Aqueux

Cette étude a pour but d’évaluer la toxicité de l’extrait aqueux de Sida acuta, une plante beaucoup utilisée en médecine traditionnelle par les populations ouest africaine et particulièrement ivoirienne. L’intérêt accordé à la dite étude est dû au besoin de garantir aux populations, une thérapie à base de plante sans risque de toxicité ou d’effet nocif. L’analyse de la phytochimie qualitative a été réalisée par la méthode de coloration en tubes et l’évaluation de la toxicité de l’extrait aqueux sur des souris blanches suivant la ligne Directrice 423 de l’OCDE, modifié en 2008. Les doses 300, 1000, 2000 et 5000 mg/kg de masse corporelle ont été administrées par gavage aux quatre lots expérimentaux. Seul le lot témoin a reçu de l’eau distillée. La phytochimie a révélé simultanément les stéroïdes et terpènes pour l’extrait aqueux et éthanolique 70% tandis que les alcaloïdes, polyphénols, et les flavonoïdes ont été révélés exclusivement dans l’extrait éthanolique 70%. La dose maximale de 5000 mg/kg de masse corporelle n’a enregistré aucun décès. Par conséquent, l’extrait aqueux de Sida acuta  reste sans danger à l’usage par voie orale en médecine traditionnelle.   This study aims to evaluate the toxicity of the aqueous extract of Sida acuta, a plant widely used in traditional medicine by West African and particularly Ivorian populations. The interest given to the said study is due to the need to guarantee populations a plant-based therapy without risk of toxicity or harmful effects. The qualitative phytochemical analysis was carried out by the tube staining method and the evaluation of the toxicity of the aqueous extract on white mice following OECD Guideline 423, modified in 2008. Doses 300, 1000, 2000 and 5000 mg/kg body weight were administered by gavage to the four experimental batches. Only the control batch received distilled water. Phytochemistry simultaneously revealed steroids and terpenes for aqueous and the 70% ethanolic extract while alkaloids, polyphenols, and flavonoids were revealed exclusively in the 70% ethanolic extract. The maximum dose of 5000 mg/kg body weight recorded no deaths. Therefore, the aqueous extract of Sida acuta remains safe for oral use in traditional medicine

LANNEA BARTERI ENGL. (ANACARDIACEAE) PLANT USED IN THE TREATMENT OF URINARY TRACT INFECTIONS IN IVORY COAST: BIOLOGICAL AND CHEMICAL STUDIES OF THE AQUEOUS EXTRACT

Objective: This research aims to evaluate the antibacterial activity and determine the chemical composition of the aqueous extract of the bark of Lannea barteri Engl. (DA) used in the traditional treatment of urinary tract infections in the Ivory Coast. Methods: The material is composed of DA, the bacterial strains of Pseudomonas aeruginosa and Acinetobacter baumannii, isolated from the urine of patients from different hospitals and subsequently stored. The qualitative analysis was performed using color-based detection tests and thin layer chromatography (TLC) reactions and the quantification of total phenols, flavonoids, flavone aglycones and anthocyanins using the method of Folin Ciocalteu. The method of diffusion on Mueller Hinton (MH) agar medium has been used for sensitivity tests. Results: The phytochemical screening of DA has revealed the presence of polyphenols, terpenes, and derivatives, coumarins, tannins, flavonoids, and alkaloids. Furthermore, the quantification of some polyphenols such as flavonoids, flavone aglycones, and anthocyanins was determined. The total polyphenols found was 0.757±0.003 mg/g MS representing respectively; 0.230±0.01 for flavonoids; 0.028±0.02 for flavone aglycones and 0.016±0.02 mg/g MS for anthocyanins. DA is bactericidal against Pseudomonas aeruginosa and Acinetobacter baumannii, which are mainly responsible for urinary tract infections. Conclusion: The bark of Lannea barteri Engl. (DA) is rich in flavonoids, flavone aglycones, and anthocyanins which are probably responsible for its antibacterial properties on Pseudomonas aeruginosa and Acinetobacter baumannii. This research thereby supports the use of this plant in the treatment of urinary tract infections

Antimicrobial Resistance of Klebsiella pneumoniae -ESBL Producing Strains Isolated from Clinical Specimens in Abidjan (Cote de Ivoire)

Aims: The objective of this study is to detect the prevalence of qnr genes in broad-spectrum beta-lactamase producing Klebsiella pneumoniae, involved in hospital and community-acquired infections. Study Design: It is a retrospective study. Place and Duration of Study: Bacteriology and virology laboratorie of Institut Pasteur, Abidjan, Côte d'Ivoire. Methodology: From January 2011 to June 2016, 350 Klebsiella pneumoniae were isolated from various clinical specimens and identified by conventional bacteriological tests. Antibiotic resistance (beta-lactams, quinolones and aminoglycosides) and detection of broad-spectrum beta-lactamases were assessed by the diffusion method and the synergy test, respectively. Molecular characterization of quinolone resistance genes (qnr A, qnr B and qnr S) was performed by the conventional polymerase chain reaction (PCR). Results: Of the 350 Klebsiella pneumoniae isolates, 91(26%) were detected as ESBL producer, 36.2% (n=33) recovered from urine, 24.2% (n=22) from pus and 20.8% (n=19) from blood culture respectively. 46(33%) strains were idenifed to carry qnr genes, qnrB predominate 33(71%), followed by qnr 12(26.1%) and qnrA 1(2.2%). The strains exhibited high resistance to most of the agents tested, expect imipemen, low resistance to amikacin 4.1%, moderate to cefoxitin 31.8% and 54.9% with amoxicillin-clauvanic acid. Conclusion: Although these observed prevalences are small proportions, this can be seen as a warning signal for the future. The emergence and dissemination of resistance genes in Côte d'Ivoire could pose a public health problem. Thus, the establishment of a relevant resistance surveillance policy to better control the circulation of multidrug-resistant strains is necessary

Antibacterial Properties of an Aqueous Extract of Solanum torvum (Solanaceae) on a Few Multidrug Resistant Bacterial Strains to Common Antibiotics

This study aimed to evaluate the antibacterial activity of the aqueous extract of Solanum torvum leaves (EASt) on multidrug-resistant bacterial strains to common antibiotics. This plant is used in traditional medicine against diarrhoea. Solid agar diffusion and liquid dilution methods were respectively used to assess the sensitivity of bacterial strains to EASt and to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Tests performed on ten (10) bacterial strains, isolated from various biological products, showed that Staphylococcus aureus 234 UB/17 and Escherichia coli 135 UB/17, were significantly sensitive to EASt, with a higher sensitivity for the latter strain. This sensitivity was shown by an inhibition of bacterial growth in solid agar and liquid medium, by a decrease in turbidity caused by EASt sensitive germs growth as the concentration of this plant extract increased (25 to 100 mg/ml). This demonstrate that EASt is an antibacterial substance. Thus, treated with EASt at a dose of 100 mg/ml, the MICs of S. aureus 234 UB/17 and E. coli 135 UB/17 were 6.25 and 12.5 mg/ml respectively, and the MBCs were 25 and 50 mg/ml respectively. The ratio of these bactericidal parameters (MBC/MIC) equaled to four (4) for these two bacterial strains, indicating that EASt is bactericidal for these bacterial strains. The antibacterial and bactericidal properties of EASt on multiple antibiotic resistant germs could justify the use of this plant in traditional medicine for the treatment of some bacterial infections causing diarrhoea

Study of the toxicity of ethanolic extract of Schrankia leptocarpa D.C in the treatment of dental caries in Côte d’Ivoire

Schrankia leptocarpa (S. leptocarpa) is a plant found in the Mimosaceae family. It is used in the treatment of dental caries in Côte d’Ivoire. Because of the direct contact of the decoction with the cells of the mouth and the risk of swallowing it, we have been interested in the study of the toxicity of S. leptocarpa. The aim of our study was to assess the risks linked to the toxicity of plant during the traditional treatments. To achieve this goal, cytotoxicity and acute oral toxicity tests of the ethanolic extract of S. leptocarpa (P) were carried out at different concentrations on Vero E6 cells from the black monkey kidneys of West Africa and on Swiss mice. This study showed a cytotoxic effect of extract P on Vero E6 cells for all the concentrations ranged from 10 to 2.5 μg/mL from the second day. This extract has been found to be no-toxic with an LD50 greater than 5000 mg/kg. At the end of this study, it was shown that S. leptocarpa could be used in the treatment of dental caries without any fear of toxicity