Two new mertoterpenoids, australins A (1) and B (2), and a new alkaloid, australine (4), together with five known compounds (3, 5-8) were isolated from the fruiting bodies of Ganoderma australe. Their structures including absolute configurations were assigned by using spectroscopic methods and electronic circular dichroism (ECD) calculations. Racemic australin A was further purified by chiral HPLC. Biological assessments reveal that compounds (+)-1 and 7 could significantly protect SH-SY5Y cells from glutamate-induced neural excitotoxicity.
Keywords: Ganoderma australe; alkaloids; meroterpenoids; neuroprotection.