Antibacterial Activity of Nigella Sativa Linn. Seeds Against Multiple Antibiotics Resistant Clinical Strains of Staphylococcus aureus

ABSTRACT

Objective: Staphylococcus aureus is one of the major resistant pathogens extremely adaptable to antibiotic pressure. Nigella sativa (black cumin) seed extracts and essential oil have been shown to possess antimicrobial activity against several bacteria but little work has been done on their effect against multidrug resistant S. aureus strains isolated from patients. So, we studied antibacterial activity of Nigella sativa against multidrug resistant clinical strains of Staphylococcus aureus. It was an experimental, in vitro study. Materials and methods: Nigella sativa (black cumin) seed essential oil and extracts were tested in varying dilutions against 40 clinical strains of Staphylococcus aureus which were isolated from patients attending a tertiary care teaching hospital in North India using disc agar diffusion technique on inoculated Muellar Hinton agar plates under standard laboratory conditions. The tested strains were resistant to 4 or more clinically used antibiotics belonging to at least 3 different classes. Results: The Methanolic extract and oil of Nigella sativa were found active against 38 and 35 multi-drug resistant strains respectively. Both the oil and Methanolic extract showed remarkable dose dependant antibacterial activity against the tested strains up to a dilution of 150 as evident from the zones of inhibition. Conclusion: Nigella sativa possesses antibacterial activity against multidrug resistant clinical strains of Staphylococcus aureus