Studies on the antimicrobial activity of Nigella sativa seed (black cumin)

Filter paper discs impregnated with the diethyl ether extract of Nigella sativa seeds (25-400 micrograms extract/disc) caused concentration-dependent inhibition of Gram-positive bacteria represented by Staphylococcus aureus. Gram-negative bacteria represented by Pseudomonas aeruginosa and Escherichia coli (but not Salmonella typhimurium) and a pathogenic yeast Candida albicans. The extract showed antibacterial synergism with streptomycin and gentamicin and showed additive antibacterial action with spectinomycin, erythromycin, tobramycin, doxycycline, chloramphenicol, nalidixic acid, ampicillin, lincomycin and sulphamethoxyzole-trimethoprim combination. The extract successfully eradicated a non-fatal subcutaneous staphylococcal infection in mice when injected at the site of infection.