Erinacerins from Hericium erinaceus: a review of their chemistry, bioactivities, and NMR characterization.

The medicinal mushroom Hericium erinaceus is a rich source of diverse bioactive secondary metabolites. Erinacerins are a significant class of structurally diverse secondary metabolites, comprising both nitrogen-containing alkaloids bearing an isoindolinone or pyridinone core and non-nitrogenous congeners. This review provides a comprehensive overview of 28 known erinacerins reported from H. erinaceus, detailing their isolation, structural elucidation, and diverse bioactivities. A key focus is directed toward their characterization by NMR spectroscopy, offering a systematic guide for the identification of this class of molecules. The discussion encompasses the reported inhibitory effects of erinacerins against enzymes such as acetylcholinesterase and α-glucosidase, as well as their anti-inflammatory and cytotoxic activities against various cancer cell lines, underscoring their pharmacological potential. This work highlights the significance of erinacerins as a valuable scaffold of bioactive metabolites for therapeutic applications.