Comparative antimicrobial activity of Moringa oleifera, Nigella sativa seed extracts, and gentamicin against Staphylococcus aureus from burn wounds

Background: In folklore, Nigella sativa and Moringa oleifera seeds have long been associated with multifaceted antimicrobial properties, although without extensive empirical scientific validation. Natural products of plant origin have been recognized as potential sources of antimicrobial agents. The antibacterial activity of Moringa oleifera and Nigella sativa against clinical isolates of Staphylococcus aureus has been previously reported in contexts other than burn infections. Objective: This study aimed to compare the antimicrobial effects of Nigella sativa seed and Moringa oleifera seed extracts with gentamicin against Staphylococcus aureus isolates from burn wound infections. The investigation was inspired by ethnobotanical surveys, ethnopharmacological records, and traditional medicinal claims regarding the therapeutic potential of these plants. Materials and Methods: Staphylococcus aureus isolates from burn wound infections were exposed to varying concentrations of Moringa oleifera and Nigella sativa seed extracts (5 µg/mL, 2.5 µg/mL, and 1.25 µg/mL), prepared via cold maceration. Gentamicin at 5 µg/mL served as the standard antibiotic control. All preparations were incubated at 37°C for 24 hours, and antimicrobial activity was assessed by measuring the zone of growth inhibition. Results: Both aqueous and methanol extracts of Moringa oleifera and Nigella sativa seeds demonstrated anti-staphylococcal activity at concentrations ranging from 5 µg/mL to 1.25 µg/mL, particularly at dilution factors of 1:2 to 1:4. However, antimicrobial activity diminished at higher dilutions (1:16 and 1:32). Notably, Nigella sativa seed extract exhibited more pronounced anti-staphylococcal effects than Moringa oleifera. Gentamicin, a broad-spectrum aminoglycoside antibiotic, displayed 100% anti-staphylococcal activity at all tested dilutions. Conclusion: Methanol extracts of Moringa oleifera and Nigella sativa seeds exhibit promising anti-staphylococcal activity and may hold potential for clinical applications as alternative therapies. Gentamicin remains a highly effective standard treatment for Staphylococcus aureus infections, including those associated with burn wounds.