alleviates dextran sulfate sodium salt-induced colitis in mice through anti-inflammation, regulating Th17/Treg balance, maintaining intestinal barrier integrity, and modulating gut microbiota.

(), an important component of Chinese herbal tea, has traditionally been used to treat hepatitis, jaundice, cholecystitis, and colitis. However, the chemical composition of and its effect against colitis remain unclear. In this study, the chemical composition of the water extract of . was analyzed using ultra performance liquid chromatography coupled with a hybrid linear ion trap quadrupole-orbitrap mass spectrometer (UPLC-LTQ-Orbitrap-MS). A total of 46 compounds, comprising -kaurane diterpenoids, flavonoids, phenolic acids, and steroids, were identified in the water extract of . , and the extract could significantly alleviate dextran sulfate sodium salt-induced colitis by improving colon length, upregulating anti-inflammatory factors, downregulating proinflammatory factors, and restoring the balance of T helper 17/T regulatory cells. also preserved intestinal barrier function by increasing the level of tight junction proteins (zonula occludens 1 and occludin) in mouse colonic tissue. In addition, . modulated the gut microbiota composition by increasing bacterial richness and diversity, increasing the abundance of beneficial bacteria (, , , and ), and decreasing the abundance of pathogenic bacteria (, , and ). Gut microbiota depletion by antibiotics further confirmed that . alleviated colitis in a microbiota-dependent manner. Overall, our findings provide chemical and biological evidence for the potential application of . in the management of colitis.