Phytochemical Characterization and Antibacterial assessment of Essential oils Derived from Teucrium stocksianum Boiss. and Selected Salvia Species

Species belonging to the genera Teucrium and Salvia (Lamiaceae) are widely recognized in ethnomedicine, particularly in the Baluchestan region, as important medicinal plants used in the treatment of ailments such as colds and gastrointestinal disorders, largely attributed to their terpene-rich essential oils (EOs). The aim of this study was to characterize the chemical composition and evaluate the antimicrobial activity of EOs obtained from selected Salvia species and Teucrium stocksianum. In the present study, EOs obtained from Teucrium stocksianum Boiss, Salvia artemisioides Boiss, Salvia abrotanoides Karel., and Salvia yangii Benth., collected from the Baluchestan region of Iran, were chemically characterized and evaluated for their antimicrobial activity. The oils were isolated by hydrodistillation and analyzed using gas chromatography–mass spectrometry (GC–MS). Antimicrobial activity was assessed by the microbroth dilution method against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis, and expressed as minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. The EO yield was ۰.۴۵% for T. stocksianum and ranged from ۰.۸% to ۱.۳۵% for the Salvia species. GC–MS analysis revealed that α-pinene (۳۶.۸۳%) and β-pinene (۱۳.۳۹%) were the major constituents of T. stocksianum oil, while ۱,۸-cineole (۳۱.۱۳%) was the predominant compound in S. yangii. Among the tested samples, the EOs of T. stocksianum and S. yangii exhibited notable antibacterial activity, particularly against E. coli, S. aureus, and B. subtilis, with inhibitory effects observed at concentrations below ۲۰ mg/ml. Importantly, the EO of T. stocksianum, rich in monoterpenes such as α- and β-pinene, demonstrated strong antibacterial potential, with low MIC values against B. subtilis (۰.۵ ± ۰.۳ mg/ml) and S. aureus (۲ ± ۰.۸ mg/ml). In contrast, the EOs of S. abrotanoides and S. artemisioides showed limited antimicrobial activity. These findings suggest that the EO of T. stocksianum is a promising natural antimicrobial agent, supporting its ethnomedicinal use and highlighting its potential applications in the development of plant-based therapeutic and preservative agents; however, further in vivo studies are required to confirm its efficacy and safety.

کلیدواژه ها:

Lamiaceae ، Ssential oils ، Secondary metabolites ، Antimicrobial activity