From computational prediction to in vitro experimental validation: Identifying active compounds in longan leaves and their anti-colorectal cancer mechanisms.

Colorectal cancer (CRC) is the third leading cause of cancer-related mortality worldwide, representing a serious threat to human life and health. There is an urgent need to develop novel therapeutic agents. Longan (Dimocarpus longan Lour.), a plant typical used for both medicinal and food purposes, has been shown in modern pharmacological studies to possess significant anti-CRC activity in its seeds and flowers. However, the active components in longan leaves and their potential anti-CRC effects remain unexplored. In this study, the ethanol extract of longan leaves (ELL) was separated and purified using ODS column chromatography and preparative HPLC. The major constituents of ELL were identified through a combination of hydrolytic monosaccharide analysis, high-resolution mass spectrometry, nuclear magnetic resonance spectroscopy, and HPLC comparison with standards. Subsequently, an integrative approach incorporating network pharmacology, molecular docking, molecular dynamics (MD) simulations, along with experimental validations-including CCK-8, apoptosis, wound healing assay, transwell assay, and Western blotting-was employed to investigate the mechanism underlying the inhibitory effect of ELL on CRC. Seven flavonoid glycosides were identified from longan leaves with five compounds reported for the first time. ELL significantly suppressed proliferation and migration, and induced apoptosis in CRC cells. Network pharmacology, molecular docking, and MD simulations suggested that the primary active compounds in ELL contributing to its anti-CRC activity are afzelin, quercitrin, and trifolin, with AKT1 as the key target. Western blot analysis confirmed that ELL markedly downregulated AKT1 protein expression. These findings indicate that ELL may serve as a potential therapeutic agent for colorectal cancer.