ABSTRACT

study was carried out to determine the in-vitro antimicrobial activity of some commercialized registered herbal drugs sold in Umuahia, Abia State. Three (3) herbal drug mixtures were purchased from different shops identified to be the major sales location for herbal drug mixture in Umuahia. The herbal mixtures were prepared by dissolving 0.4ml of the mixture in 2ml of (DMSO) Dimethyl Sulfoxide to give 200mg/ml stock solution. The strains of microorganism used as test organisms were Escherichia coli, Staphylococcus aureus, Bacillus specie, and Salmonella species. This study revealed that the in-vitro antimicrobial activity of the herbal mixtures varied against the test isolates. It was revealed that at concentration of l00mg/ml, Staphylococcus aureus showed the highest sensitivity to HD-Z (21.0mm) followed E. coli with high sensitivity (22.0mm) against HD-Z. It was observed in this study that the herbal mixture (HD-Z) showed more significant inhibitory effect on the test organisms than the HD-X and HD-Y. The herbal mixture (HD-Z) recorded a pronounced antibacterial activity against the test organisms with zones of inhibition varying between 13mm to 22mm against E. coli at the concentration of 1 00mg/ml, while HD- Y showed minimal antibacterial activity against the isolates with zones of inhibition varying between 12mm to 19mm against Staphylococcus at the concentration of 1 00mg/ml. The minimum inhibitory concentration (MIC) concentration test result showed that the herbal mixtures had strong inhibitory effect against Bacillus spp and Salmonella spp with concentration values of 80mg/ml. The antimicrobial activity of these herbal mixtures has been related to the presence of bioactive phytochemicals of the herbs. Hence, the herbal mixtures could be useful in the treatment of infant respiratory infections and a potential source of antibacterial agents and raw material for the pharmaceutical industry if adequately explored.