Abstract
Skin-associated bacteria play a significant role in various dermatological conditions. Essential oils (EOs), known for their broad-spectrum antimicrobial properties, have emerged as promising alternatives to conventional treatments for bacterial skin infections. However, studies on the potential of EOs for treating these infections have largely centered on Staphylococcus aureus. As such, this study evaluated the antimicrobial activity of six EOs-rosemary, eucalyptus, lavender, basil, sage, and thyme-against methicillin-sensitive S. aureus (MSSA), methicillin-resistant S. aureus (MRSA), Staphylococcus epidermidis, and Cutibacterium acnes. Among the tested EOs, thyme EO exhibited the strongest antibacterial activity with the lowest minimum inhibitory concentration (MIC; 0.07-2.81 mg/mL) and (minimum bactericidal concentration (MBC; 0.07-11.22 mg/mL) values. In contrast, basil EO displayed the weakest activity, with the smallest inhibition zones observed against S. aureus MSSA (37.00 ± 1.80 mm), MRSA (34.50 ± 10.40 mm), and S. epidermidis (35.30 ± 1.30 mm), as well as the highest MIC (12.11-24.22 mg/mL) and MBC (12.11 to >24.22 mg/mL) values. Eucalyptus and lavender EOs showed MIC values ranging from 5.67 to 22.65 mg/mL and 5.54 to 22.16 mg/mL, respectively, and corresponding MBC values from 5.67 to >22.65 mg/mL and 5.54 to >22.16 mg/mL, though their activity was lower than that of thyme EO. Further analysis using flow cytometry confirmed the antibacterial activity of these oils, revealing that their mechanism of action involves disrupting bacterial membrane integrity. S. epidermidis exhibited the greatest resistance to EO treatments, and C. acnes was the most susceptible species. Additionally, the ability of EOs to inhibit MRSA highlights their potential as an alternative treatment for drug-resistant skin infections.IMPORTANCEEssential oils (EOs) are widely known and often used to support pain relief, better sleep, immune health, and protection against germs or inflammation. In this study, we tested six EOs to see how effectively they could fight bacteria linked to common skin issues like acne, dermatitis, and eczema. Thyme oil showed the strongest antibacterial effect, while basil oil was the weakest. These oils work by damaging bacterial membranes, leading to bacterial death. Their effectiveness depends on the type of bacteria, so they could be used alone or combined with standard treatments. Eucalyptus and lavender oils also performed well, suggesting they may complement existing therapies for skin infections.