Phytochemical investigation and molecular docking studies of Ruellia simplex extract on human breast cancer cell line

This study investigated phytochemical constituents of Ruellia simplex extract and evaluated their molecular interactions with estrogen receptor alpha (ERα) and cytotoxic effects against MCF-7 breast cancer cells. The whole plant was extracted with ethanol and fractionated into methanolic (ME01) and chloroform (CH02) fractions. HR-LCMS identified 11 compounds in ME01 and 8 in CH02, with flavonoids predominating in ME01 and terpenoids in CH02. Molecular docking against ERα (PDB ID: 3ERT) revealed five potent compounds: stigmasterol (-9.0 kcal/mol), apigenin (-8.6 kcal/mol), rosmarinic acid (-8.6 kcal/mol), luteolin (-8.4 kcal/mol), and β-sitosterol (-8.3 kcal/mol). MTT assay demonstrated superior cytotoxicity of ME01 (IC₅₀ = 38.42 ± 2.16 μg/mL) compared to CH02 (52.64 ± 3.05 μg/mL), approaching 5-Fluorouracil (32.18 ± 1.87 μg/mL). Results demonstrate that Ruellia simplex contains bioactive compounds with significant ERα binding affinities and notable cytotoxic activity against breast cancer cells. The ME01 fraction shows promise for developing natural anticancer agents targeting hormone-dependent breast cancers.