Bioactive isoindolinone alkaloid from Hericium erinaceum

Hericium erinaceum (Hericiaceae) is an edible mushroom which is widely distributed in China, Japan and Korea. Some phytochemical constituents, phenolics, fatty acids and sterols have been reported from this source and a wide range of biological activities, including antimicrobial, macrophage activation, NK cell activation, neuroprotective effects were studied. In a continuing search for bioactive constituents from Korean mushrooms, we performed a phytochemical investigation of the MeOH extract from the fruiting bodies of H. erinaceum. By repeated column chromatographic separation of the extract one new isoindolinone alkaloid (1), together with eleven known compounds (2-12) were isolated. The identification and structural elucidation of the compounds was based on 1D and 2D NMR spectral data. The cytotoxic activities of the isolated compounds (1-12) were evaluated by determining their inhibitory effects on human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15) in vitro using the sulforhodamine B (SRB) assay.