Objectives: To evaluate the in vitro antifungal activity of extracts and compounds from Trichilia catigua against clinically relevant Candida species, notably Candida glabrata, and investigate possible mechanisms of action using electron microscopy and in silico techniques.
Methods: Extracts and fractions of T. catigua were obtained through turboextraction and partitioning, while the isolated compounds were previously purified. The ethyl acetate fraction (EAF) was characterized by HPLC. Antifungal activity against C. glabrata was evaluated through MIC tests, synergism was assessed via checkerboard assays, and structural changes were analyzed via electron microscopy. Molecular docking was performed to identify potential targets of action.
Results: The EAF and isolated compounds (cinchonains and procyanidin B2) exhibited significant activity against C. glabrata, with MICs of 9.76 µg/mL (EAF) and 3.9 µg/mL (cinchonains Ia and Ib). Cinchonain Ib combined with epicatechin or procyanidin B2 displayed synergistic effects, particularly with amphotericin B. Microscopy analysis revealed cell membrane damage, and reverse docking analysis suggested that the compounds may target an enzyme essential to the metabolic processes of C. glabrata.
Conclusions: The findings suggest that compounds isolated from T. catigua hold considerable potential for developing new antifungal agents against Candida species, particularly C. glabrata, with promising safety and synergistic profiles.
Keywords: Candida; Trichilia catigua; checkerboard; electron microscopy; molecular docking.
We wanted to see if a tree from Brazil, called “catuaba,” could help stop the fungus Candida. This fungus can make people very sick, especially in hospitals. Some medicines don’t work against Candida anymore, so we investigated catuaba extracts as an alternative treatment. We tested the bark from the catuaba tree to see if it could stop the fungus. We found that parts of the tree can stop the fungus from growing. When mixed these tree parts with established medicines, it worked even better and killed the fungus faster. We also found out that “catuaba” does not hurt healthy cells. Our findings suggest promise of these extracts to be used in future medicines.