Phytochemical Profiling, Antioxidant Capacity, Cytotoxicity, and In silico Androgen Receptor Binding Interactions of the Aqueous–Ethanol Root Extract of Cnestis ferruginea Vahl ex DC. (Connaraceae)

Male infertility affects an estimated 55 million men worldwide, with prevalence rising across sub-Saharan Africa where affordable interventions remain limited. Oxidative stress is a key driver of male reproductive dysfunction, disrupting spermatogenesis via lipid peroxidation, DNA damage, and impaired androgen receptor (AR) signalling. Medicinal plants with antioxidant and AR-interacting phytoconstituents offer an underexplored strategy for fertility-modulating lead discovery. Cnestis ferruginea Vahl ex DC. (Connaraceae), a West African shrub used ethnomedicinally for male sexual dysfunction, lacks molecular-level pharmacological evidence. This study reports the phytochemical profile, GC–MS composition, DPPH antioxidant activity, brine shrimp lethality, and in silico AR binding of C. ferruginea aqueous–ethanol root extract (AECF). Cold maceration (65:35 v/v ethanol–water) yielded 4.70% (w/w) extract containing flavonoids, phenols, terpenoids, steroids, saponins, tannins, phlobatannins, and reducing sugars. GC–MS identified 17 compounds (89.27% of the profile), dominated by methyl benzoate (67.12%). Docking against the AR ligand-binding domain (PDB: 2AM9) showed methyl benzoate scored −2.632 and −2.921 kcal/mol at AR Sites 1 and 2, comparable to testosterone (−2.539 and −2.926 kcal/mol), with slightly superior binding. All key constituents satisfied Lipinski’s Rule of Five, supporting oral bioavailability. DPPH assay gave an IC50 of 97.94 µg/mL (vs 34.60 µg/mL for ascorbic acid), indicating moderate antioxidant activity; brine shrimp lethality gave an LC50 of 347.80 ppm, indicating moderate cytotoxicity. These findings provide the first computational evidence for AR-mediated androgenic potential of C. ferruginea, supporting its traditional use in male reproductive health and identifying methyl benzoate as a priority candidate for isolation and in vivo validation.