Antimicrobial Activity of Ethanol Extracts and Isolated Fractions Shorea robusta Gaertn f and Dipterocarpus turbinatus Gaertn f

Background: Shorea robusta and Dipterocarpus turbinatus are widely used by the indigenous people of North Eastern state Tripura in their daily life for various purposes. Objectives: The present investigation was aimed to evaluate the antimicrobial activity of S. robusta and D. turbinatus bark extracts and their different fraction by disk diffusion and turbidimetric methods. Methods: Plant materials were extracted with different solvents in successive manner and the extracts were screened for antimicrobial activity by disc diffusion. Results: As the ethnaollic extracts of both the plants showed good antimicrobial activity, we fractionated the ethanolic extracts with different solvents using a separating funnel to obtain specific solvent soluble fractions. The ethyl acetate soluble fractions and residual ethanolic fractions were effective against several bacterial and fungal pathogens. The ethyl acetate fractions were further fractioned using silica gel column chromatography (60-120) as an adsorbent and the isolated fractions were further tested for their antimicrobial activity by turbimetric methods. Conclusion All isolated fractions had antimicrobial activity, with most of the isolated fractions show activity against gram negative bacteria.