Title : Alignment of Iranian indigenous knowledge and the effect of essential oil of Stachys inflata Benth. against Pseudomonas aeruginosa
Abstract:
Due to the indiscriminate use of antibiotics, the emergence of multidrug-resistant bacterial and fungal strains has significantly increased, prompting a growing interest in discovering novel and safe antimicrobial molecules from plant metabolites. Stachys inflata Benth., a native species widely distributed in Iran, is traditionally utilized for disinfection, treating respiratory diseases, skin problems, and wound healing. This study aimed to investigate the anti-Pseudomonas aeruginosa activity of S. inflata essential oil collected for the first time from the Kashan region, Isfahan Province, Iran. The essential oil was extracted via hydro-distillation using a Clevenger apparatus, and its chemical composition was analyzed using GC-MS. The antimicrobial activity was evaluated by determining the Minimum Inhibitory Concentration (MIC) using the broth dilution method. The results revealed that non-terpene compounds (42.22%) and sesquiterpenes (45.06%) constituted the majority of the essential oil compounds, distinct from previous regional reports. Notably, the MIC value against the Gram-negative bacterium P. aeruginosa was 15.63 μg/mL, demonstrating twice the potency of the control antibiotic, rifampin. Given that prior studies reported no inhibitory effects of this plant on this bacterium, these findings suggest that distinct habitat conditions influence the biological traits and chemical profile (predominance of acidic compounds and sesquiterpenes) of the plant. These results validate the traditional medicinal applications of S. inflata as a potent natural antibacterial agent.
