TAGRA 2025

Antibiotic resistance remains one of the most pressing global health challenges, driving the urgent need for innovative strategies that can enhance the effectiveness of existing antimicrobial agents. Essential oils derived from medicinal plants, such as thyme (Thymus vulgaris), contain bioactive compounds with recognized antibacterial potential and may serve as promising adjuvants to conventional antibiotics. This study investigates whether thyme essential oil can improve the antibacterial efficacy of two commonly used antibiotics—erythromycin (15 µg) and amoxicillin (10 µg)—against methicillin-resistant Staphylococcus aureus (MRSA), a clinically important multidrug-resistant pathogen. Disk diffusion assays were performed to determine inhibition zone diameters for antibiotics alone and in combination with 10 µL of thyme essential oil.The results showed that amoxicillin and amoxicillin–clavulanate produced no inhibition zones against MRSA, consistent with the known resistance profile of this organism. However, the addition of thyme essential oil resulted in an inhibition zone of approximately 13 mm, demonstrating a notable improvement in antibacterial performance. Erythromycin alone also exhibited no inhibitory effect on MRSA, whereas its combination with thyme essential oil generated an inhibition zone of approximately 9 mm, indicating enhanced activity attributable to the essential oil. These findings highlight the ability of thyme essential oil to partially restore or augment the antibacterial action of antibiotics that are otherwise ineffective against MRSA in vitro. Overall, the study supports the growing body of evidence suggesting that essential oils can act as effective adjuvants by increasing membrane permeability, facilitating antibiotic entry, or exerting complementary antibacterial effects. The integration of thyme essential oil with conventional antibiotics may contribute to improved treatment outcomes, reduced required antibiotic dosages, and a potential slowdown in resistance development.