Comparative study of phytochemical and synergistic anti-bacterial activity of Tribulus terrestris (L.) and Pandiaka heudelotii (Moq.) Hien on some clinical bacterial isolates

Objective: This research work focus on synergistic effect of ethnomedicinal plants namely, Tribulus terrestris and Pandiaka heudelotii methanolic and aqueous leaves extracts on two species of clinical bacterial isolates namely, Staphylococcus aureus and Escherichia coli, using disc diffusion method.Methods: The leaves were collected, air dried, pulverized and extracted by maceration. The extracts were subjected to preliminary phytochemical screening using standard procedures. The susceptibility test of individual plant as well as the synergistic effect of combinations of the plants extract was carried out using disc diffusion method.Results: Collectively the plant extracts revealed the presence of alkaloids, flavonoids, steroids, saponins, glycosides, amino acids, reducing sugars and tannins. The in-vitro antimicrobial activity of the crude extracts was examined against both the plants leaves extract showed antibacterial activity against the tested microorganisms. However, some of the eluents collected from methanolic extract fractions of column chromatography were also showed activity on tested organisms. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the leaves extract were determined within the ranges of (125 to 250 mg/ml) and (250 to 500 mg/ml) respectively, the highest synergistic activity was attained against E. coli by combined both methanolic P. heudelotii and T. terrestris extract which showed a zone of (27.54±00).Conclusions: The result indicates antibacterial activity of the leaves extract of P. heudelotii in combination with that of T. terrestris against the clinical bacterial isolates tested and laid credence to the advantage of the combination of the two plants over the two other individual forms. Statistically using, Microsoft excel version 2010.