Development and in vitro Antifungal Evaluation of a Ternary Essential Oil–Based Oral Phytopharmaceutical Formulation Against Candida albicans

Katherine Cuenca-León,1– 4 Edisson-Mauricio Pacheco-Quito,1,2 Miriam Lima-Illescas,1– 3 Aránzazu Zarzuelo-Castañeda3 1Facultad de Ciencias de la Salud, Carrera de Odontología, Universidad Católica de Cuenca, Cuenca, Ecuador; 2Research Group: Innovación y Desarrollo Farmacéutico en Odontología, Carrera de Odontología, Jefatura de Investigación e Innovación, Universidad Católica de Cuenca, Cuenca, Ecuador; 3Department of Pharmaceutical Sciences, University of Salamanca, Salamanca, Spain; 4Ecuadorian Network of Women Scientists (REMCI), Catholic University of Cuenca Node, Quito, EcuadorCorrespondence: Katherine Cuenca-León, Email [email protected]: The increasing resistance of Candida albicans to conventional antifungal agents has intensified the search for alternative therapies based on natural metabolites.Aim: This study aimed to evaluate the phytochemical profile and antifungal activity of a phytopharmaceutical formulation composed of essential oils from Cymbopogon citratus (lemongrass), Coriandrum sativum (coriander), and Origanum vulgare (oregano), obtained by steam distillation from plants collected in the southern region of Ecuador.Methodology: The chemical composition was characterized by gas chromatography coupled with mass spectrometry (GC–MS). A total of 40 compounds were identified, with carvacrol (30.01%), α-citral (12.57%), β-citral (9.55%), linalool (8.47%), (E)-2-decenal (8.38%), and geraniol (2.81%) as the major constituents. Antifungal activity was assessed using the agar diffusion method against C. albicans ATCC 90028, comparing formulations at 2.5%, 5%, 10%, and 25%.Results: The ternary formulation at 10% in an alcoholic vehicle exhibited the largest inhibition zone (77.89 ± 2.48 mm), significantly surpassing both positive controls, including 0.12% chlorhexidine gluconate (35.13 ± 0.01 mm) and fluconazole (21.63 ± 6.29 mm). The aqueous formulation also demonstrated considerable antifungal activity, although lower than the alcoholic system.Conclusion: The novel phytopharmaceutical formulation demonstrated notable antifungal activity and may represent a promising natural alternative for oral candidiasis management. Nevertheless, further studies incorporating complementary methodologies, such as minimum inhibitory and fungicidal concentration (MIC/MFC) assays, as well as in vivo and biocompatibility evaluations, would contribute to strengthening the translational potential and clinical applicability of these findings.Keywords: phytopharmaceutical formulation, essential oils, GC–MS, Candida albicans, antifungal formulation