Cytotoxic Triterpenes from Argan Pulp (Argania spinosa): Isolation, In Vitro Evaluation on Cancer Cell Lines, and In Silico Studies

Abstract

This study focuses on the isolation, characterization, and evaluation of cytotoxicity of triterpenes extracted from argan pulp. The unsaponifiable lipids extracted from argan pulp are separated into five fractions, two of which are triterpene fractions F2 (composed of α-amyrin, β-amyrin, lupeol, ψ-taraxasterol, taraxasterol) and F4 (erythrodiol). The extraction process utilized solvent-based methods followed by purification through column chromatography. Structural elucidation was carried out using GC-MS and NMR techniques. The cytotoxic activity of the fractions was evaluated against HepG2, MCF-7, and HeLa cell lines. Fraction F4 exhibited IC50 values of 45.58, 71.24, and 98.80 µg/mL, respectively, while fraction F2 showed IC50 values of 122.6, 167.8, and 212.7 µg/mL. Annexin V–FITC/PI flow-cytometry analysis was performed on HepG2 cancer cells and THLE-2 non-tumor cells treated with F4. The results showed a concentration-dependent increase in apoptosis in HepG2 cells, with minimal necrosis. To complement the experimental results, computational analyses were performed to evaluate the pharmacokinetic properties. The triterpenes showed favorable drug-like characteristics and low predicted toxicity. Molecular docking revealed strong interactions with key cancer-related targets, including BCL-2, estrogen receptor α, and HPV16 E6.