Evaluation of bioactive compounds from Libidibia ferrea (Mart. Ex Tul) LP Queiroz: Antioxidant and antifungal activities, acetylcholinesterase inhibition, and implications in Alzheimer's disease.

Fungal infections caused by Candida albicans represent a global health concern, with increasing antifungal resistance and potential links to neurodegenerative diseases such as Alzheimer's. In this context, this study evaluated the antifungal, antioxidant and acetylcholinesterase inhibitory activities of the hydroethanolic leaf extract of Libidibia ferrea, a species used in traditional medicine. The antioxidant potential was determined using DPPH and ABTS assays, while acetylcholinesterase inhibition was assessed by an in vitro enzymatic assay. Antifungal activity was assessed against Candida albicans strains by broth microdilution and molecular docking was employed to predict the interactions of the main phenolic compounds with acetylcholinesterase and sterol 14-α-demethylase. The extract showed potent antioxidant activity (CI₅₀ = 9.68 ± 0.51 μg/mL for DPPH) and high inhibition of acetylcholinesterase (CI₅₀ = 15.02 ± 0.16 μg/mL). It also showed fungistatic and fungicidal effects, with MIC values ​​ranging from 0.118 to 0.469 mg/mL. In silico analyses highlighted rutin, catechin and ellagic acid as compounds with strong binding affinities to both enzymes, suggesting dual antifungal and neuroprotective effects. These results corroborate Libidibia ferrea as a promising source of bioactive compounds with potential therapeutic applications for fungal infections and neurodegenerative diseases, such as Alzheimer's.