Biological Characterization and Essential Oil Profiles of Eastern European Cultivars of Thymus, Satureja, and Monarda

Thymus, Satureja, and Monarda are three plant genera, belonging to the Lamiaceae family, that are particularly valued for their essential oils (EOs) abundant in phenolic terpenoids. In this study, a botanical characterization of the following eight Eastern European cultivars (some of them newly bred) grown in Ukraine is distinguished: Thymus vulgaris (‘Yalos’, ‘101’), Thymus richardii (‘Fantasia’), Satureja montana (‘Krymsky smaragd’, ‘Lunata’, ‘4-18’), Monarda fistulosa (‘Premiera’), and Monarda × hybrida hort., which is a Monarda didyma × Monarda fistulosa hybrid (‘Tonya’). The EO of those cultivars was obtained and characterized in detail using GC-MS and GC-FID. Additionally, some biological activities of these oils were tested. Antimicrobial activity was verified against Escherichia coli, Staphylococcus aureus, and Candida albicans using disk diffusion and microdilution methods. Furthermore, some preliminary tests were performed on the motility of bull sperm using the CASA system. All the Thymus cultivars were very rich in thymol (57.99–67.62%), and all the S. montana cultivars were very abundant in carvacrol (62.22–75.53%). M. fistulosa cv. ‘Premiera’ contained mainly thymol (49.87%), and M. × hybrida cv. ‘Tonya’ contained both thymol (46.70%) and carvacrol (10.37%). All the tested EOs, as well as thymol and carvacrol, exhibited strong antibacterial and antifungal action with minimal inhibitory concentrations ranging from