Highly oxygenated lanostane-type triterpenoids and their bioactivity from the fruiting body of Ganoderma gibbosum

Eight new highly oxygenated lanostane triterpenes, gibbosic acids A-H (1-8), along with three known ones (9-11), were isolated from the fruiting body of Ganoderma gibbosum. The structures of new isolates were assigned by NMR and HRESIMS experiments. The absolute configurations of 1 were further confirmed by single crystal X-ray diffraction data and computational ECD methods. Immunoregulatory effect and anti-inflammatory activities of these compounds were screened in murine lymphocyte proliferation assay and in lipopolysaccharide (LPS)-stimulated RAW-264.7 macrophages, respectively. Compound 2 exhibited immunostimulatory effect both in lymphocyte proliferation assay without any induction and ConA-induced mitogenic activity of T-lymphocyte, and the proportion of lymphocyte proliferation at the concentration of 0.1μM are 20.01% and 21.40%, respectively.