Antimicrobial Activity of Psoralea corylifolia Linn. (Baguchi) Seeds Extracts by Organic Solvents and Supercritical Fluids

Abstract

Objective: To determine the antimicrobial activity of organic and supercritical fluids extracts of Psoralea corylifolia seeds against both Gram +ve bacteria (S. aureus ATCC- 29213 and MRSA -15187) and Gram ‐ve bacteria (E. coli ATCC-6739 and P. aeruginosa ATCC- 9027). Methods: The supercritical fluid extracts of Psoralea corylifolia were prepared by using pure CO2 and CO2 with co-solvent ethyl acetate. On the other hand, organic solvents extracts were prepared sequentially by using petroleum ether, dichloromethane, ethyl acetate, methanol, hydro alcohol (50%) and water. The antibacterial activities of all prepared extracts (PCE 1- PCE 11) were studied along with different marker compounds (bakuchiol, psoralen, isopsoralen and psolaridin) using Broth Dilution method. Results: The results clearly indicates that all prepared seeds extracts and the marker compound from Psoralea corlyfolia shows significant antibacterial activity against Gram +ve bacteria, whereas the extracts (PCE 6 - PCE 11) and the compound psolaridin were found to inactive against Gram ‐ve bacteria. Out of eleven prepared extracts, two extracts namely PCE 1 and PCE 2 along with bakuchiol was found to be more active against all tested micro‐organisms, especially against Gram +ve S. aureus ATCC- 29213 and MRSA – 15187 bacteria. On the other hand, the extract (PCE 1 - PCE 5) along with marker compounds (bakuchiol, psoralen and isopsoralen) shows significant inhibitory effect of against Gram ‐ve bacteria. Conclusion: It was observed that the extract of Psoralea corylifolia seeds were active against both Gram +ve bacteria and Gram ‐ve bacteria. Moreover, the present work clearly demonstrates that the presence bakuchiol has a key role for antimicrobial activity of Psoralea corlyfolia.