Abstract We have contributed to the valorization of a flora plant of beninese used traditionally in antibacterial infections. We have prepared hydroethanolic extract from powdered dried leaves of Arbrus precatorus (Fabaceae).We did a split bioguided from the crude hydro-ethanolic extract. We have isolated and purified by the series of methods chromatography two flavonoids from the active methanolic fraction of the crude hydro-ethanolic extract of the dried leaves of A. precatorius. The spectrometric analyzes carried out, namely mass spectrometry, proton and carbon nuclear magnetic resonance, made it possible to identify the following molecules. These are 5-hydroxy-2-(4hydroxy-3-methoxyphenyl)-7-methoxy-4-oxo-4H-chromen-3-yl acetate and (E)-2-(4-methoxybenzylidene)-5,7dihydroxy-2,3-dihydroinden-1-one. The added value of the work lies in the fact that these two molecules have never been identified before in this plant and therefore constitute an avenue for developing a therapeutic arsenal to fight recurrent microbial infections.
Keywords isolation, chromatographic methods, spectrometric analyzes.