PHYTOCHEMICAL AND IN VITRO ANTIMICROBIAL EVALUATION OF ETHANOLIC EXTRACTS OF PROSOPIS JULIFLORA (SW.) DC (FABACEAE)

Abstract

Prosopis juliflora, a multipurpose dry land tree or shrub introduced to Kenya due to concern about desertification,deforestation and fuelwood shortages, has become invasive, forming dense, impenetrable thickets, associatedwith unfavorable impacts on human economic activities. It has soothing, astringent, antifungal and antisepticproperties and is commonly used to treat eye conditions, open wounds and dermatological ailments. Anassessment of phytochemical composition and antimicrobial activity of ethanolic extract of root(REE) andleaves(LEE) of P. juliflora against clinical isolates of Candida albicans, Staphylococcus aureus(ATCC-25923), Bacillussubtilis , Escherichia coli (ATCC-25922) and Pseudomonas aeruginosa (ATCC-27853) was carried out using paperdisc diffusion method. The results of investigation showed that all the extracts had inhibitory effect on the growthof all the isolates. Only chloramphenical, erythromycin and minocycline were effective against all the bacterialstrains tested and there was no significant difference (P > 0.05) between the activity of REE and LEE at the highestconcentration compared to the activity of chloramphenical, erythromycin and minocycline. S. aureus showed thelowest susceptibility to most of the conventional drugs while B. subtilis was most susceptible to chloramphenical.All the bacterial strains exhibited susceptibility to erythromycin and minocycline while Penicillin, methicillin andampicillin were the least effective antibiotics. Both LEE and REE exhibited better antifungal activity compared tocotrimoxazole and all the extracts had saponins, tannins and alkaloids; phytochemicals whose antimicrobialproperties are well documented. Results from this study strongly validate use of P. juliflora in the management ofmicrobial infections.Key words: Gram negative, gram positive, antimicrobial, phytochemicals