ASSESSING THE ANTIMICROBIAL ACTIVITY OF OREGANO, THYME AND ARBORVITAE ESSENTIAL OILS

Essential oils (EOs) possess antimicrobial activity and may be able to provide a natural alternative to the treatment of bacterial and fungal infections within humans. Oregano, Thyme, and Arborvitae, in particular, possess strong antimicrobial activity. This research assessed the ability of essential oils to act as effective antibacterial agents against Staphylococcus lugendensis and Corynebacterium xerosis, both known for causing human bacterial infections. Furthermore, the essential oils were tested against the fungal strain Candida albicans, a common cause of fungal infections, to assess their antifungal activity. An agar gel disc-diffusion assay was used to assess both the antibacterial and antifungal activity of these oils at a 50% dilution with DMSO on bacterial and fungal strains. A minimum inhibitory concentration (MIC) using the serial dilution method starting with a 10% essential oil solution was also determined. The three EOs possessed antimicrobial activity at a 50% concentration against all three microbial strains. Oregano had average zones of inhibition of 36.6, 26.6, and 33.6 mm against S. lugdunensis, C. xerosis, and C. albicans, respectively. In the same respect, Thyme had average zones of inhibition of 30.8, 24.4, and 33.4 mm and Arborvitae had average zones of inhibition of 27.6, 20.8, and 27.4 mm, respectively. All EOs had significantly larger zones of inhibition than the DMSO control (p\u3c0.01). Oregano had a MIC of 0.078125% against all three microbial strains. Thyme had a MIC of 0.15625% against C. albicans and S. lugdunensis and a MIC of 0.078125% against C. xerosis. Arborvitae had a MIC of 0.078125% against S. lugdunensis and C. xerosis. A MIC was not determined for Arborvitae against C. albicans. DMSO, the control, had a MIC of 25% against all three microbial strains. These results indicate that EOs could be used as a natural alternative to treating topical infections