In Vitro Sensitivity of Salmonella typhi Strain to Essential Oils of Syzygium aromaticum and Cymbopogon citratus, Medicinal Plants Used in the Kisangani Region (DR Congo)

The growing resistance of Salmonella typhi to antibiotics is a major public health challenge, justifying the search for natural therapeutic alternatives. This study aims to evaluate in vitro the antibacterial activity of essential oils of Syzygium aromaticum and Cymbopogon citratus on a strain of S. typhi isolated in Kisangani in the Democratic Republic of Congo. The essential oils were extracted by hydrodistillation and characterized organoleptically and physicochemically. Antibacterial activity was evaluated using the agar diffusion method, supplemented by determination of the minimum inhibitory concentration (MIC), and then statistically analyzed by ANOVA. The results show a higher extraction yield for S. aromaticum (0.85%) than for C. citratus (0.31%). The essential oil of S. aromaticum showed more pronounced antibacterial activity (inhibition diameter: 10 mm) compared to that of C. citratus (3 mm) and the reference antibiotics. The MIC of S. aromaticum was estimated at 80%, indicating concentration-dependent activity. Thus, the essential oil of S. aromaticum is an effective source of natural antibacterial agents against S. typhi, although further studies (molecular and in vivo) are needed.