Therapeuticpotential Of The Partition Of The Aqueousextract Of The Leaves Of Terminalia Leiocarpa (Dc.) Baill. (Combretaceae) Againstmultidrug-Resistantpseudomonas Aeruginosa Infections

Abstract

The Ivorian pharmacopoeia is characterized by its richness and diversity, offering numerous phytotherapeutic alternatives for common ailments. Terminalia leiocarpa (DC.) Baill. (Combretaceae) remains an important medicinal plant due to its traditional antibacterial properties. To provide scientific evidence supporting this traditional use, the present study evaluated the antibacterial activity of alcoholic fractions (chloroform, ethyl acetate, and n-butanol) and the residual aqueous fraction of the plant against seven strains of Pseudomonas aeruginosa, comprising six clinical isolates (four resistant and two wild-type strains) and one reference strain. Agar well diffusion and broth macrodilution methods were used to assess bacterial susceptibility and determine antibacterial parameters. The n-butanol fraction demonstrated the highest activity; at 50 mg/mL, it produced the largest inhibition zone (25 ± 1.3 mm) against the in vitro growth of P. aeruginosa strain 885C. Overall, all fractions exhibited significant antibacterial activity, with an identical minimum inhibitory concentration (MIC) of 0.019 mg/mL. Although minimum bactericidal concentration (MBC) values varied slightly, they remained statistically comparable, indicating similar antibacterial activity among the organic and residual aqueous fractions. Phytochemical screening by thin-layer chromatography (TLC) revealed the presence of several secondary metabolites, including terpenes, saponins, polyphenols, flavonoids, xanthones, naphthoquinones, alkaloids, tannins, coumarins, and anthrones. The presence of these bioactive compounds may contribute to the observed antibacterial activity. These findings provide scientific support for the traditional use of T. leiocarpa in Ivorian traditional medicine.