ANTIBACTERIAL ACTIVITY OF NIGELLA SATIVA EXTRACTS AGAINST EXTENDED SPECTRUM Β-LACTAMASE PRODUCING ESCHERICHIA COLI ISOLATES

The most striking feature of natural products in connection to their long-lasting importance in drug discovery is their structural diversity that is still largely untapped. Most natural products are not only sterically more complex than synthetic compounds but also differ in regards to the statistical distribution of functionalities. The chemical diversity and unique biological activities of a wide variety of natural products have propelled many discoveries in chemical and biological sciences and provided therapeutic agents to treat various diseases as well as offered leads for the development of valuable medicines. The present study has been designed to screen the phytochemicals and to evaluate the antibacterial potential of Nigella sativa L. seeds against ESBL positive Escherichia coli isolates. The crude extracts of Nigella sativa L. seeds were prepared by utilizing two methods namely Soxhlet extraction and Supercritical Fluid Carbon dioxide (SCFE-CO₂) extraction. Preliminary phytochemical analysis revealed the presence of alkaloids, flavonoids, phenols, tannins, saponins, and terpenoids which are known to exhibit medicinal as well as physiological activities. The Supercritical Fluid Carbon dioxide (SCFE-CO₂) extracts of Nigella sativa L. seeds exhibited high activity against ESBL E. coli as compared to other crude extracts. These antibacterial properties would assure for further studies on the clinical applications of Nigella sativa L. against multidrug clinical isolates.