ANTIBACTERIAL ACTIVITY OF BACILLUS MEGATERIUM LEAF EXTRACT

摘要

The antibacterial activity of methanolic leaf extract of Ervatamia heyneana was studied. Ervatamia heyneana is a small deciduous tree grown in southwest India. The plant is used for the treatment of wounds, inflammation of the cornea, sore eyes and some skin diseases and is also used as emmenagogue, aphrodisiac, tonic, purgative; tonic to the brain, liver and spleen. The antimicrobial activity was screened by using broth dilution method and agar well diffusion method against both gram positive and gram negative bacterial strains. The four bacterial species used in the test were Methicillin-resistant Staphylococcus aureus (MRSA), Bacillus megaterium, Proteus vulgaris and Pseudomonas aeroginosa. The results indicated that the methanolic extract of Ervatamia heyneana showed antibacterial activity against the tested bacteria. The length of inhibition zone was measured in millimeters from the edge of the well to the edge of the inhibition zone. The zones of inhibition exhibited by Ervatamia heyneana ranged between 13mm and 29mm. The minimum inhibitory concentration (MIC) exhibited by the extract ranged between 0.1 and 5mg/mL. The methanolic extract of Ervatamia heyneana showed highest sensitivity against Pseudomonas aeruginosa while lowest activity against Staphylococcus aureus. The antibiotics Penicillin and Streptomycin showed MIC values varying between lOug/mL and 300ug/mL. The leaf extract was more active against gram negative bacteria than gram positive bacteria.