In silico activity and effect of synthetic chalcones on Candida albicans and Candida tropicalis biofilms

Abstract

Biofilm formation is considered one of the most important virulence factors for Candida species, which presents an extracellular matrix of polymeric substances that limits the passage of antifungals, leading to fungal resistance. Therefore, the present study investigated the biofilm eradication effect of synthetic chalcones against Candida albicans and Candida tropicalis. Molecular docking studies were conducted to verify the mechanism of action of chalcones on Candida species proteins. The biofilm eradication effect was determined using crystal violet methodology to quantify biomass and Thiazolyl blue tetrazolium bromide (MTT) to verify the influence on metabolic activity. A molecular docking study was also carried out with Candida proteins using the Protein Data Bank repository (https://www.rcsb.org/) and Autodocktools™ software. The results showed that (1E,4E)-1,5-diphenylpenta-1,4-dien-3-one (DB-Acetone), (1E,3E,6E,8E)-1,9-diphenylnona-1,3,6,8-tetraen-5-one (DB-CNM), and (1E,4E)-1,5-bis(4-methoxyphenyl)penta-1,4-dien-3-one (DB-Anisal) were able to eradicate the biomass of C. albicans CA INCQS 40006 (ATCC 10231), while fluconazole only reduced the biomass at the three tested concentrations (IC₅₀, IC₅₀ × 10, and IC₅₀ × 20) against C. tropicalis CT INCQS 40042 (ATCC 13803). Both chalcones and fluconazole successfully reduced metabolic activity across all tested strains. The molecular docking study concluded that DB-Acetone, DB-Anisal, and DB-CNM exhibited significant affinity energy values toward the binding sites of C. albicans and C. tropicalis. It is concluded that the synthetic chalcones showed promising results in inhibiting Candida spp. biofilm, demonstrating efficacy in reducing biomass as well as metabolic activity.