This study was conducted to determine the antimicrobial activity of the three morphotypes of Eclipta alba against gram positive bacteria: Staphylococcus aureus, Bacillus subtilis and gram negative bacteria: Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa. Disc diffusion method was used to test the antimicrobial activity of methanol, acetone and aqueous extracts of the leaves of the three morphotypes of E. alba. The study showed that these extracts have antimicrobial activity against all the bacteria except P. aeruginosa. Comparison of activity index of various types of extracts has shown that aqueous extracts were least effective. The acetone extracts of all the three morphotypes showed more antimicrobial activity against S. aureus, E. coli and K. pneumoniae than methanol extracts. The methanol leaf extracts of erect and intermediate type of E. alba showed maximum activity against B. subtilis. Among the three morphotypes the leaf extracts of erect type of plants showed maximum antimicrobial activity against all the bacteria except B. subtilis where the extracts of prostrate type showed maximum activity.
