ABSTRACT

In vitro antibacterial activities of crude extract of Chromoleria odorata and Emilia sonchfihia were investigated against some human pathogens including Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans using the agar well diffusion and broth dilution techniques. The ethanolic crude extract of both plants exhibited significant inhibitory action against all the isolates tested at an initial concentration of 200mg/mi except for Candida albicans. The zones of inhibition exhibited by the extract against the tested organisms ranged between 12.0 and 16.5mm for the ethanol extract of Chromoleria odorata and 11.5 to 14.0mm for the Emilia sonchifilia extract, while the zones of inhibition exhibited by Gentamicin used as standard antibiotic control ranged between 19 and 21mm. There was a corresponding decrease in the zone of inhibition of the growth of the pathogens as the concentration of the extracts decreased. The minimum inhibitory concentrations exerted by the ethanol extract of Chromoleria odorata against the bacterial isolates ranged between 12.5mg/ml and 25mg/mi while that of Emilia sonchifilia was also between 12.5mg/mi and 25mg/mi. The percentage yields of phytochemical content of the leaves of the Chromolena odorata and Emilia sonchiflia plants were as follows: alkaloids (1.63%, 2.09%), flavonoids (0.79%, 1.36%), saponins (6.05%, 0.9 1%), and tannins (0.74%, 0.82%) respectively. The result shows that the leaves of these plants have appreciable amount of these phytochemicals, hence their medicinal value. Chromolena odorata had the highest amount of saponin (6.05%) when compared with those of Emilia sonchifilia (0.91%). The significant antibacterial activities exhibited by the ethanol extracts of the plants confirmed the therapeutic potentials of these plants in treatment of various infections in herbal medicine.