Iranian Medicinal Plants Society Journal of Medicinal plants and By-products 2322-1399 15 3 2026 05 01 Antimicrobial Properties and Essential Oil Profile of Ziziphora clinopodioides Lam. from Three Regions of Lorestan Province 394 401 135272 10.22034/jmpb.2026.369463.1969 EN Soheila Afkar Agriculture Department, Payame Noor University, Tehran, Iran Leili Shokoohizadeh Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran Journal Article 2025 05 12 This study was conducted to identify one of the endemic medicinal plants and its use in medical science. With this aim, the quantity and quality of essential compounds in the <em>Ziziphora clinopodioides</em> plant under various environmental conditions and its antimicrobial activity against <em>Staphylococcus aureus</em> and <em>Escherichia coli</em> using the disk diffusion method were investigated in three regions of Lorestan Province. These regions including region 1 (Borujerd), region 2 (Khorramabad) and region 3 (Aleshtar). 25, 27 and 21 compounds were identified in regions 1, 2, 3 respectively. The main compounds in regions 2 (Khorramabad) and 3 (Aleshtar) were Pulegone, Isomenthone and P-mentha- 3,8 -diene. The main constituents of the essential oil extracted from samples collected in region 1 (Borujerd) differed significantly from those obtained from the other two regions. Thymol, E- Caryophyllene, Carvacrol and γ-Terpinene were the main components of region 1. Significant negative correlation between soil organic carbon percentage and β-myrcene composition. The findings indicated that the essential oil of <em>Z. clinopodioides</em> collected from region 1 exhibited notable antimicrobial properties against both <em>S. aureus</em> and <em>E. coli</em> compared to regions 2 (Khorramabad) and 3 (Aleshtar). The different compositions of essential oil of plant collected from region 1 from regions 2 and 3 can be attributed to the distinct climatic and geographical conditions of region 1. the results of this research showed that the difference in the geographical conditions of the growing region of the <em>Z. clinopodioides</em> plants studied in this research has caused a significant difference in the components of the essential oil compounds, their amount and their antimicrobial effects, which can be used to improve the essential oil compounds in the pharmaceutical, health and food industries. It is suggested to investigate the effect of the main components of the essential oil separately for a better understanding of the mechanism of antimicrobial activity. https://jmpb.areeo.ac.ir/article_135272_1c69f09707fdacdfd5b6089b6493bac0.pdf