RESUMO
BACKGROUND: The aim of this study is to investigate the antimicrobial activities of the species belonging to the genera Origanum L., Thymus L., and Thymbra L. in the Lamiaceae family and molecular characterization using ISSR markers and to determine the correlations between anti-microbial activities of the plant extracts and ISSR loci. METHODS AND RESULTS: Anti-microbial active extracts were obtained after 24-hours extraction using either of the three different solvents (ethanol, hexane, and chloroform) from the plants using the Soxhlet device. The effects of extracts on the bacterial strains (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis) were determined using the disc-diffusion method. The species Thymbra spicata var. spicata L., Thymus vulgaris L., Thymus citriodorus, Thymus cilicicus, Origanum syriacum L., and Origanum vulgare L. subsp. hirtum displayed significant anti-microbial activities, while the Origanum minutiflorum, Origanum onites L., Origanum saccatum and Origanum vulgare L. ssp. gracile displayed less activities on the bacterial strains. The plant species under study had a high level of genetic diversity. Significant correlations were determined between the anti-microbial activities of the plant species and the ISSR loci. CONCLUSION: Staphylococcus aureus was the most sensitive and Pseudomonas aeruginosa was the least sensitive strain. The ethanol and chloroform extracts were the most effective solvents. ISSR markers were successful for determining high levels of genetic diversity and clustering the species belonging to the genera Origanum, Thymus, and Thymbra. Conducting molecular marker analyses facilitated in distinguishing the species correctly for molecular breeding studies. The studies identified the antimicrobial activities of the plants against the bacteria used in the study and suggested their potential role in the pharmaceutical industry.