Thiosemicarbazones and analogues as potential biofilm inhibitors of Candida albicans.

Biofilms are a virulence factor for Candida albicans, a common pathogen in human fungal infections, making them resistant to many commercial antifungals. Therefore, the discovery of compounds that inhibit and eradicate biofilms is a priority. As thiosemicarbazones have had their effect on Candida biofilms little explored, this study investigated the inhibitory and eradication activity of 30 thiosemicarbazones and analogues against C. albicans biofilms. After initial screening, four compounds were selected and compound 28 emerged as the most potent with BIC50 at 31.55 ± 1.18 µM. By scanning electron microscopy analysis, blastoconidia adhered to the reduced surface and reduced formation of pseudohyphae and hyphae was revealed. Despite the inhibitory activity, the four compounds failed to eradicate the biofilm by more than 50%. Thus, the results suggest that the compounds evaluated are very promising for the development of effective antibiofilm compounds and open up new perspectives for elucidating the mechanism of action.