In Africa, and particularly in Benin, medicinal plants are the most widely used means of solving human and animal health problems. The Beninese flora is rich in plants used to treat gastrointestinal diseases of farm animals whose chemical and biological potentials are still unknown. It is to correct this insufficiency that the present work aims at the chemical and biological recovery of Khaya senegalensis. After phytochemical screening, the phenolic compound contents of Khaya senegalensis extracts were determined spectrophotometer. Antibacterial and antiradical activities were evaluated by microplate dilution methods and DPPH respectively. The active ingredients of K. senegalensis were characterized by GC/MS. Several metabolites have been identified. The crude extracts (ethanolic, hydroethanolic and aqueous extracts) of K. senegalensis showed a lower antiradical activity compared to ethyl ether (IC50=0.09 μg/ml) and ethyl acetate (IC50=1μg/ml) fractions, which are more active that BHA (IC50= 4.8μg/ml), quercetin (IC50=3μg/ml) which are synthetic compounds. From the antibacterial activity, it appears that the objective extracts and fractions of this plant have a bactericidal activity with respect to Escherichia coli and Klebsiella pneumoniae. From the results of the chromatographic analysis, it appears that the bark of K. senegalensis contains glycerol, glycerol ethanoate, pyrocatechol, octadecanamide and neoergosterone as major components. The diversity of metabolites, the anti-fungal and antibacterial activities of K. senegalensis, could justify the use of this plant in the veterinary pharmacopoeia in Benin.

A proliferation of hotels in major cities in developing countries such as Benin leads to more waste water production. The present work aims to evaluate the efficiency of the wastewater treatment methods of Cotonou hotels. But after investigation, most hotels do not have a wastewater treatment plant. During the investigation, wastewater samples were collected and analyzed. The measurement of the field parameters was made with a pH meter, a conductivity meter and a turbidimeter. BOD5 was measured by respirometry and COD by colorimetry. A molecular absorption spectrophotometer was used to measure: suspended matter, total nitrogen and total phosphorus content. Microbiological parameters were determined by the incorporation technique. These analyzes show that the effluents at the entrance of the stations are heavily loaded with pollutants. However, significant declines are observed on site n°4 (activated sludge) with non-standard values only for phosphorus and Escherichia coli. The adoption of a disinfection and phosphorus removal treatment would make it possible to obtain water of acceptable quality for reuse of these waters in irrigation.