Excretion characteristics of main compounds of Yigong San in urine, feces, and bile of rats

Abstract Yigong San (YGS) is a traditional Chinese medicine formula used for pediatric anorexia, chronic atrophic gastritis, and irritable bowel syndrome. In this study, the excretion of eight main compounds, including liquiritin; isoliquiritin; hesperidin; ginsenosides Rb 1 , Re, and Rg 1 ; and atractylenolides I and II, in rat urine, feces, and bile, was investigated by ultra‐high performance liquid chromatography–tandem mass spectrometry. The results showed that the cumulative excretion rates of the compounds in rat urine, feces, and bile were 0.018–1.15%, 0.024–19.89%, and 0.0025–0.72%, respectively. Among the eight compounds detected, liquiritin was the richest in urine, and ginsenosides Re and Rg 1 and atractylenolide I were mainly found in feces and bile. In summary, the main components of YGS are excreted via multiple approaches. Liquiritin is mainly through urine, whereas isoliquiritin; hesperidin; ginsenosides Rb 1 , Re, and Rg 1 ; and atractylenolides I and II are mainly through feces. The excretion of these compounds in bile is usually positively correlated with that in feces. This study lays a foundation for further pharmacological research and application of YGS.