Fourteen lanostane triterpenoids were identified from the sclerotia of edible fungus Poria cocos.
Four new lanostane triterpenoids (1–4) were structurally elucidated.
Compounds 8 and 13 were isolated for the first time from P. cocos.
Compounds 1, 2, 6, 12, and 14 inhibited NO production in LPS-activated RAW264.7 macrophages.
The mechanism of action for the most active compound 14 was examined.
Poria cocos Wolf confers large, edible sclerotia, known as ‘Indian bread’ in North America. Chemical investigation of EtOH extract of the sclerotia of P. cocos resulted in the identification of four new lanostane triterpenoids (1–4), coriacoic acids A-D, and 10 known compounds (5–14). The structures of the new compounds were determined by spectroscopic analysis, including 1D and 2D NMR spectra, and HRMS. Among the known isolates, compounds 8 and 13 were isolated for the first time from P. cocos. All compounds 1–14 were tested for their inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW264.7 macrophages. Compounds 1, 2, 6, 12, and 14 inhibited NO production with IC50 values ranging from 49.43 to 82.32 μM. Among them, compound 14 was the most active compound, and its anti-inflammatory effect was found to be mediated through the inhibition of iNOS and COX-2 expression via downregulation of NF-kappaB.