Objective To investigate the chemical constituents of the branches of Broussonetia papyrifera and screen for compounds with cytotoxic activity against primary effusion lymphoma (PEL) cells. Methods The compounds were isolated and purified by various chromatographic techniques including silica gel, RP-18, Sephadex LH-20, and MCI column chromatographies, as well as high-performance liquid chromatography (HPLC). Their structures were identified by spectroscopic methods. The cytotoxicity of the isolates against PEL cell lines (BC-3 and BCBL-1) was evaluated using the CCK-8 assay. The effects of active compounds on cell apoptosis and cell cycle distribution were analyzed by flow cytometry. Results Nineteen compounds were isolated and identified as broussoflavonol B (1), 8-prenylquercetin-3-methyl ether (2), taxifolin (3), liquiritigenin (4), (＋)-medioresinol (5), (＋)-syringaresinol (6), dadahol B (7), diospyrosin (8), balanophonin (9), 5-methoxybalanophonin (10), isokhellactone (11), nodakenetin (12), rutamarin (13), smyrindiol (14), marmesin (15), 8-methoxymarmesin (16), 7-demethylsuberosin (17), umbelliferone (18), and n-hexacosyl (E)-p-coumarate (19). Compounds 1,7 and 17 exhibited significant inhibitory activity against PEL cells. Among them, compound 7 showed half-maximal inhibitory concentration (IC₅₀) values of 16.05 and 16.90 μmol/L against BC-3 and BCBL-1 cells, respectively. Further studies indicated that compound 7 could notably induce apoptosis and arrest cell cycle in PEL cells. Conclusion Compounds 8,17 and 19 were isolated from the Moraceae for the first time, while compounds 9—11 and 13 were obtained from the genus Broussonetia for the first time. Compound 7 exerts its anti-PEL activity by inducing cell apoptosis and blocking cell cycle progression.

Broussonetia papyrifera (L.) L'Hé  /  r.ex Vent  /  dadahol B  /  diospyrosin  /  7-demethylsuberosin  /  n-hexacosyl (E)-p-coumarate  /  primary effusion lymphoma  /  cytotoxic activity