ABSTRACT

The stem and leaves of the three plants (Justicia carnea , Boerhavia diffusa and Emilia sonchifolia) were screened for phytochemistry and antimicrobial activity. The crude components were extracted using ethanol and water. The ethanol and water extracts of the leaves and stems were tested against Escherichia coli, Staphyloccocus aerus , Streptococcus pneumonia, Klebsiella pneumonia and Proteus vulgaris, using disc diffusion method and the result were compared with standard antibiotic disc of chlorophenicle. The ethanolic stem of Justicia carnea showed activity against E.coli with diameter zone of inhibition of l2.5±0mm and also with diameter zone of inhibition 7.0±0mm. The same extract showed activity against P.vulgaris showing the zone of inhibition of 12.5±0.71mm and 8.0±l.41mm respectively. The ethanolic leaves and aqueous stem and leaves had no activity against the other test organisms. The ethanolic stem extract of Boerhavia diffusa showed activity against S.aerus and S.pneumonia which the inhibition zone ranges from 13.5±0.70mm, 10.5±0.70mm and 8.5±0.70 against S.pneumonia with diameter zone of inhibition of l2.5±0.70mm and I1.5±0.70mm while the ethanoic leaf extract showed activity against E.coli and S.aerus with diameter zone of inhibition of 12.5±0.70mm and 10.0±10.4lmm. The aqueous stem and leaves showed no activity on the tested organisms.The ethanolic stem extract of Emilia sonchifolia showed activity against E. coli, P. vulgaris, S. aerus and K. pneumonia ranges with diameter zone of inhibition of l2.5±0.7lmm and 10.5±1.41mm, 10.5±1.41mm and 9.5±0.70mm, 14.0±1.4 lmm and I 1.5±0.70mm and 9.5±0.70mm respectively. The ethanolic extract showed activity against S.aerus and S.pneumonia with diameter zone of inhibition of 12.540.70mm and 9.5±0.70mm and I l.5±1.23mm and 10.0±0.0mm respectively. While the aqueous stem and leaf showed activity against S, aerus and S. pneumonia with diameter zone of inhibition of 1 l.5±2.l3mm and 9.5±2.13mm respectively. Phytochemical screening showed that tannins, alkaloids, and phenol were active compounds present in (Justicia carnea, Boerhaavia diffusa, and Emilia sonchifolia). Justicia carnea stems extract has a moderate content of saponin and has low content of flavonoids which could be the reason for its weak activity against the test organism. The ethanolic stem and leaves extracts had the highest inhibitory activity on the test organism probably because they contain more compounds than the aqueous stem and leaves extract. Out of the three plants (Justicia carnea. Boerhaavia diffusa, and Emilia sonchifolia), Boerhavia dffusa and Emilia sonchifolia may be useful for the treatment of some diseases whose causative agents are susceptible to its invitro antibacterial activity.