Isolation and Characterization of Phytoconstituents from Lepidium meyenii Roots, Antioxidant Activity and Molecular Docking Analysis forAlzheimer's Disease

Background: Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by memory impairment and cognitive decline. Oxidative stress and cholinergic dysfunction are key contributors to its pathogenesis. Objective: This study aimed to characterize the isolated compounds of Lepidium meyenii roots and assess its neuroprotective and anti-oxidant properties. Methods: Phytochemical screening, compound isolation, and characterization were performed on the ethyl acetate extract. Antioxidant activity was assessed using DPPH, NO, and H2O2 assays. Enzyme inhibition studies for acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were conducted in vitro. Molecular docking studies were performed to evaluate binding affinities of isolated compounds to AChE and BChE, and in vitro experiments were carried out to assess cognitive and motor function improvement. Results: The isolated compound quercetin and ergosterol exhibited significant antioxidant activity in DPPH (IC50- 35.65 ± 0.064 and 49.54 ± 0.075 µg/mL), NO (IC50- 30.48 ± 0.092 and 38.73 ± 0.030 µg/mL), and H2O2 (IC50- 24.8 ± 0.17 and 51.4 ± 0.13 µg/mL) assays. In vitro studies demonstrated potent inhibition of AChE and BChE enzymes. Molecular docking confirmed strong binding affinities of the isolated compounds with AChE and BChE. Furthermore, in vitro studies revealed that Lepidium meyenii treatment improved cognitive and motor functions progressively. Conclusion: The findings suggest that Lepidium meyenii possesses neuroprotective properties, likely mediated by its antioxidant activity and enzyme inhibition potential. These results highlight Lepidium meyenii as a promising candidate for the treatment of AD and other neurodegenerative disorders.