Deyno, Serawit; Mtewa, Andrew G.
Description:
Echinops kebericho Mesfin is traditionally used for the treatment of various infectious diseases. This study investigated antibacterial activity of the essential oil (EO) and the different fractions of ethanol extract. The most active component was isolated and identified. Isolation and purification was accomplished using chromatographic techniques while identification was done by spectroscopic method. Minimum inhibitory concentration (MIC) was determined using the broth micro-dilution method. In bioactiveguided isolation, percent inhibition was determined using optical density (OD) measurement. The MICs of the essential oil ranged from 78.125μg/ml to 625μg/ml, and its activity was observed against methicillin-resistant Staphylococcus aureus (MRSA, NCTC 12493). Ethyl acetate fraction showed high activity against MRSA (NCTC 12493), MIC 39.075μg/ml followed by Enterococcus faecalis (ATCC 49532), MIC 78.125μg/ ml and was least active against Klebsiella pneumoniae (ATCC 700603), MIC 1,250μg/ ml. MIC of hexane fraction ranged from 156.2µg/ml to Escherichia coli (ATCC 49532) to 1,250μg/mltoE.coli(NCTC11954).TheMICsofchloroformfractionrangedfrom312.5to 2500μg/ml; while butanol fraction could be considered pharmacologically inactive as its MIC value was 2,500μg/ml for all and no activity against E. coli (NCTC 11954). Dehydrocostus lactone was successfully isolated and identified whose MIC was 19.53μg/ml against MRSA. Dehydrocostus lactone isolated from E. kebericho M. showed noteworthy antibacterial activity which lends support to ethnopharmacological