Tricholoma and Lanostane Triterpenoids from <i>Tricholoma terreum</i> and Their Anti-Inflammatory Assessment

<i>Tricholoma terreum</i> is an edible mushroom widely consumed in Europe and China. In this study, we investigated the chemical constituents of the fruiting bodies of wild <i>T. terreum</i> collected from Yunnan province, China, which led to the identification of seven novel nor-tricholoma-type triterpenoids, tricholoterreins A-G (<b>1-7</b>), along with two known tricholoma triterpenoids (<b>8</b> and <b>9</b>) and four lanostane triterpenoids (<b>10-13</b>). Their structures were established by detailed spectroscopic analyses as well as equivalent circulating density calculations and single-crystal X-ray diffraction. Apart from compound <b>11</b>, 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 <b>1</b> and <b>5</b> could suppress the secretion of TNF-α and IL-6 and the expression of iNOS and COX-2 protein. It is suggested that <i>T. terreum</i> is a good resource for tricholoma triterpenoids, which exhibit promising anti-inflammatory applications.