Antioxidant activity, Alpha-glucosidase inhibition, and in silico molecular docking of Vitellaria paradoxa C.F. Gaertn fruit

Abstract

Vitellaria paradoxa , has been traditionally utilized in African medicine due to its nutritional and therapeutic benefits; however, its bioactive profile and molecular mechanisms are still not thoroughly investigated. Hydrogen Peroxide (H₂O₂) Scavenging Activity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, ferric reducing antioxidant power (FRAP) Assay and Alpha-glucosidase Inhibition were evaluated. Compounds were identified via gas chromatography and Mass spectrometer and subjected to molecular docking. V. paradoxa fruit demonstrates pharmacological activity that is dependent on the solvent used, with ethyl acetate producing the highest total flavonoid content (121.5 mg QE/g) and phenolic content (142.5 mg GAE/g). The most potent radical scavenging activity was observed in the ethanol extract (IC 50 = 3.8 µg/mL), followed by significant H 2 O 2 (IC 50 = 11.8 µg/mL). Furthermore, the ethyl acetate fraction exhibited the FRAP at 39.5 mmol Fe²⁺/g. Molecular docking simulations identified Oleanan-12-en-3-ol as the best binder of 3AJ7 (3AJ7, -138.2 kcal/mol) with interactions between LYS156, PRO312, ARG315 and TYR158 and methyl linoleate as a superior Human Peroxiredoxin 5 (PRDX5, PDB ID: 1HD2) (-133.7 kcal/mol) binder via binding to VAL70, ARG95 and LEU62. The high negative binding energy of Oleanan-12-en-3-ol directly translates the low IC 50 value of the ethylacetate extract because of the stable, thermodynamically and robust interaction of the enzyme active site and the compound. These combined in vitro and in silico findings imply that the fruits of V. paradoxa are rich in multifunctional phytochemicals that exhibit strong antioxidant and α-glucosidase inhibitory properties. Future studies should adopt animal models and clinical trials.