Chemical study, antiradical and antibacterial potential of the extracts of Ximenia americana and Cussonia arborea of Benin

Abstract

This paper reports the chemical and biological studies of two plants, Ximenia americana and C. arborea used by farmers in Benin in the treatment of animal’s gastrointestinal diseases.  We noted in both samples, the presence of several secondary metabolites such as saponins, catechin tannins, mucilages, flavonoids, anthocyanins, reducing compounds, sterols and terpens. The total polyphenol content was higher in the aqueous extract of two plants than in ethanolic and hydroethanolic extracts. Those of aqueous extracts were respectively (6.419 ± 0.335) mg EA / g MS for X. americana trunk bark and (3.110±0.132) mg EA /g DM for C. arborea. The trunk bark extracts of X.americana have DPPH scavenging activities of 5µg / ml and 4μg / ml, betters than those of C. arborea. The ethanolic extract of this plant (X. americana) was more active (IC₅₀=4μg/ml) than BHA (IC₅₀= 4.8μg / ml) which was a synthetic antiradical. The results of antibacterial activity indicate that all extracts (ethanolic, hydroethanolic and aqueous) of the trunk bark of X. americana have inhibited strains of S. aureus, K. pneumoniae and S. typhi. The three extracts of this plant have showed a bactericidal activity against E. coli and aqueous extract also displayed a bactericidal one against K. pneumonia.  S. typhi got a pronounced sensitivity with ethanolic and aqueous extracts of trunk bark of C. arborea.