Flash Chromatography-Based Phytochemical Profiling and Pharmacological Evaluation of Pithecellobium dulce (Roxb.) Benth Leaves

Abstract

Background: Pithecellobium dulce (P. dulce), plant widely distributed in tropical regions, is traditionally
recognized for its nutritional and therapeutic value. Although its antibacterial, anti-inflammatory, antidiabetic,
hepatoprotective, antioxidant, and anticancer activities are well reported, its neuroprotective potential remains
largely unexplored. Objective: This study aimed to evaluate the antioxidant and anti-Alzheimer activities of the
90% ethanol extract of P. dulce leaves (EEPD). Methods: Preliminary phytochemical screening was conducted to
identify major bioactive constituents. Antioxidant activity was assessed using the DPPH free radical scavenging
assay. EEPD was fractionated by flash chromatography guided by thin-layer chromatography (toluene: ethyl
acetate, 9:1), and enriched fractions were characterized using LC-MS. Cytotoxicity and neuroprotective effects
were evaluated in SH-SY5Y neuroblastoma cells, with memantine as the reference drug. Results: EEPD contained
flavonoids, alkaloids, tannins, terpenoids, steroids, and phenolic compounds. It exhibited the strongest antioxidant
activity with the lowest IC₅₀ value among tested extracts. Phenolic-rich fractions showed significant neuroprotective
effects, enhancing SH-SY5Y cell viability and demonstrating notable anti-Alzheimer activity comparable to
memantine. Conclusion: The study highlights the potent antioxidant and neuroprotective properties of P. dulce
leaves, supporting their potential for developing plant-based therapeutics for neurodegenerative disorders.