Chemical Composition, Antifungal Activity, and Cytotoxic Effects of Indonesian Origanum vulgare Essential Oil

Objective: This study aimed to determine the phytochemical profile, antifungal activity, and cytotoxic effects of Origanum vulgare essential oil cultivated in North Sumatra, Indonesia (IOVEO).Materials and Methods: Essential oil was extracted from O. vulgare leaves by hydrodistillation and analyzed using gas chromatography flame ionization detection (GCFID) and gas chromatography/mass spectrometry (GC/MS). The antifungal activity of IOVEO against Candida albicans was evaluated using the disc diffusion method. Its cytotoxic effects were assessed using an MTT assay with oral squamous cell carcinoma (OSCC) cell lines and normal human gingival fibroblast cells.Results: Phytochemical analysis identified 23 compounds, with germacrene D (20.54%), trans-β-ocimene (16.67%), and β-caryophyllene (11.20%) as the major constituents. At a 100% concentration, IOVEO produced a strong inhibition zone against C. albicans (26.23 ± 1.01 mm), exceeding that of nystatin. Inhibition zones of 17.65 ± 1.10 mm and 9.02 ± 0.03 mm were observed at 50% and 25%, respectively, whereas concentrations from 12.5% to 0.195% showed minimal to negligible inhibition. The MTT assay further demonstrated that IOVEO exerted strong inhibitory activity against OSCC cells while showing lower toxicity toward normal human gingival fibroblasts.Conclusion: These findings support the potential of IOVEO as a natural antifungal agent. Its selective cytotoxicity against OSCC cells further suggests possible dual therapeutic relevance in fungal infection and oral cancer. Further studies are required to clarify its mechanisms of action and evaluate its translational potential in oral health applications.