PHYTOCHEMICAL SCREENING FROM LEAVES OF DATURA STRAMONIUM L. AND JUSTICIA SCHIMPERIANA AND EVALUATION OF THEIR ANTIMICROBIAL PROPERTIES AGAINST SELECTED HUMAN ENTERIC BACTERIA

The growing phenomenon of antibiotic resistance, particularly to pathogenic microorganisms, in current medicine, has directed the concern of scientists for finding novel antimicrobial agents from plant origin with negligible side effect. The aim of this study was to screen the major secondary compounds of leaves of D. stramoinum and J. schimperiana and to evaluate their antimicrobial properties against (S. aureus, S. typhi and S. boydii). Extraction was done by maceration of leaf powders using ethanol as a solvent. Antimicrobial activities of both plant species leaf extracts were determined by disc diffusion and broth dilution methods.The result of phytochemical analysis showed the presence of alkaloid, flavonoids, saponin, steroid, tannin and terpenoidin leaves of both plant species and absence of phylobatannin. All quantified compounds were found in higher amount in J. schimperiana (phen-3.14, alk-410, sap-586.6, and terp-323.3 mg/ml) than in D. stramonium (phen-3.23, alk-42.3, sap-46.3 and terp-39 mg/ml). Results of antibacterial assay revealed that extracts of both planAt species showed inhibitory activity against both the tested bacterial pathogens. Max inhibition was recorded against S. boydii (23.3±3.055) and min inhibition against S.typhi (19±1.000) by leaf extract of D. stramonium. In the other hand, for J. schimperiana max inhibition was recorded against S. boydii (8±1.000) and min inhibition against S. aureus (3±1.000). Lowest MIC in Datura leaf was recorded against S. aureus (2.5 mg/ml) and maximum MIC was recorded against S. boydii (0.625) mg/ml). For J. schimperiana the maximum MIC was recorded against S. boydii (5.0 mg/ml) and minimum MIC against S.aureus and S. Typhi (10 mg/ml). Based on this result it is concluded that leaf extracts of both tested plant species have the major secondary metabolites and antibacterial activities against the tested bacterial isolates.