Isoeugenol and Hybrid Acetamides against Candida albicans Isolated from the Oral Cavity

Isougenol is a phytoconstituent found in several essential oils. Since many natural products are potent antimicrobials, the synthesis of hybrid molecules-combining the chemical skeleton of the phytochemical with synthetic groups-can generate substances with enhanced biological activity. Based on this, the objective of this study was to evaluate the antifungal activity of isoeugenol and hybrid acetamides against Candida albicans isolated from the oral cavity. The methodologies used were the determination of minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), action on fungal micromorphology, interaction test with nystatin by the checkerboard method and molecular docking study with important enzymes in the maintenance of fungal viability. The synthetic molecules did not demonstrate significant antifungal activity in vitro. The isoeugenol MIC and MFC varied between 128 and 256 µg/mL, being the phytoconstituent able to interfere in the formation of blastoconid and chlamydoconid structures, important in the pathogenic process of the species. The molecular docking study revealed that isoeugenol is a potential inhibitor of the enzymes 14-α-demethylase and delta-14-sterol reductase, interfering in the fungal cell membrane biosynthesis. Thus, this research provides clearer expectations for future pharmacological studies with isoeugenol and derived molecules, aiming at its therapeutic application against infections caused by Candida spp.

Keywords: Candida albicans; antifungal activity; checkerboard method; isoeugenol; molecular docking; oral candidiasis.