TITLE:
Wild Oregano Oil as a Potent Natural Antimicrobial Agent: Formulations of Oil-in-Water Emulsions
AUTHORS:
Amra Bratovcic, Amela Becirovic
KEYWORDS:
Wild Oregano Oil, Antimicrobial Activity, Oil-in-Water Emulsions, Carvacrol, Formulations
JOURNAL NAME:
Journal of Biomaterials and Nanobiotechnology,
Vol.17 No.1,
January
22,
2026
ABSTRACT: The search for natural antimicrobial agents has gained increasing attention in cosmetics and therapeutics. This study evaluated the antimicrobial potential of wild oregano oil (Origanum vulgare), almond oil, and lavender macerate oil, as well as their incorporation into natural oil-in-water (O/W) cosmetic emulsions. Lavender macerate was prepared by soaking lavender flowers in almond oil for two months. Antimicrobial activity was tested against Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), and Candida albicans (ATCC 90028). Wild oregano oil exhibited potent, broad-spectrum antimicrobial and antifungal activity, completely inhibiting all tested strains, whereas almond oil and lavender macerate showed no detectable activity. FTIR analysis confirmed the presence of characteristic ester and alkyl functional groups. Based on literature data, Carvacrol can be identified as the key bioactive compound responsible for the strong antimicrobial effects. Eleven O/W emulsions were formulated using almond oil, lavender macerate, jojoba oil, and wild oregano oil. While all emulsions were sterile, their antibacterial activity was limited. Emulsions (E7, E8, E9, E10, and E11) containing almond oil above 15% in combination with Tween 20 and Lanette O (2:1) showed modest inhibition zones (2 - 4 mm) against S. aureus, but no activity against E. coli, suggesting that the observed effects likely arose from the surfactant system rather than the oil itself. Emulsions containing jojoba oil appeared to suppress antibacterial effects, highlighting the critical role of formulation in determining antimicrobial performance. These findings confirm wild oregano oil as a highly effective natural antimicrobial agent and emphasize that both intrinsic bioactivity and formulation factors govern the efficacy of cosmetic emulsions. The study provides a foundation for developing safe, natural, and potent antimicrobial formulations for applications in cosmetics, food preservation, and alternative therapeutics.