Tricholoma and Lanostane Triterpenoids from Tricholoma terreum and Their Anti-Inflammatory Assessment

Tricholoma terreum is an edible mushroom widely consumed in Europe and China. In this study, we investigated the chemical constituents of the fruiting bodies of wild T. terreum collected from Yunnan province, China, which led to the identification of seven novel nor-tricholoma-type triterpenoids, tricholoterreins A-G (1-7), along with two known tricholoma triterpenoids (8 and 9) and four lanostane triterpenoids (10-13). Their structures were established by detailed spectroscopic analyses as well as equivalent circulating density calculations and single-crystal X-ray diffraction. Apart from compound 11, all tested compounds demonstrated significant inhibitory activity against NO production in LPS-induced RAW264.7 macrophages, exhibiting IC₅₀ values under 25 μM. Further, ELISA and Western blot analysis showed that compounds 1 and 5 could suppress the secretion of TNF-α and IL-6 and the expression of iNOS and COX-2 protein. It is suggested that T. terreum is a good resource for tricholoma triterpenoids, which exhibit promising anti-inflammatory applications.