MICROSTRUCTURAL ANALYSIS OF THE MORPHOLOGY AND CELLULAR ARRANGEMENT OF Candida albicans AFTER CONTACT WITH PROPOLIS ETHANOLIC EXTRACT

Candida albicans is the most common fungal species in humans and is responsible for causing a wide variety of mucocutaneous infections in healthy people, as well as causing serious systemic diseases in immunocompromised patients. The striking feature of C. albicans morphology is its ability to differentiate into a filamentous form (hyphae or pseudohyphas), from the yeast form to the filamentous form, a polimorphic capacity of C. albicans is a determinant of virulence and plays a key role in the infection process. With increasing fungal resistance to conventional treatments, there is a great need for discovery of new drugs and research of antifungals based on natural products has aroused great interest of the pharmaceutical industry. Therefore, the aim of this study was to analyze the morphology and cellular arrangement of C. albicans after the exposure of the propolis ethanolic extract (PE). The evaluation of the morphology and cellular arrangement of C. albicans ATCC 90028 treated with PE was performed by Scanning Electron Microscopy (SEM). The concentrations of the compound used correspond to its minimum inhibitory concentration (MIC), sub-MIC and 2x MIC. Cells were obtained from the 48 h culture in a 24-well plate after contact with PE. The cell were fixed with 2.5% (v / v) glutaraldehyde solution in 0.1 M cacodylate buffer. After fixation, the cells were washed in 0.1 M buffer. Following the cells were subjected to a series of alcoholic washes in increasing concentrations of 70%, 80%, 90%, 95% and 100% ethanol. Finely, the cells were dried to the critical point, covered with a layer of gold and observed by SEM. The analysis revealed that C. albicans cells treated with PE presented structural and morphological changes in their cell wall when compared to the control group (without PE). Furthermore, there was a great reduction in the number of cells with the presence of blastoconidia with rough surfaces, and the presence of hyphae was observed only in the positive control, that is, without the presence of the PE, suggesting that the PE possesses the ability to inhibit the cellular differentiation of C. albicans to the filamentous form, making it a promising alternative for the research of new antifungals