OBJECTIVE  To explore the correlation between changes in intestinal toxicity and changes in component composition of the Mongolian medicine Euphorbia pekinensis Rupr (EPR) before and after processing with milk.

  METHODS  Mice were given 95% ethanol extract of raw EPR, milk-processed EPR and water-processed EPR by gavage. The purgative effect and intestinal inflammatory toxicity changes of EPR before and after milk processing were investigated using the fecal water content and the levels of inflammatory factors TNF-α and IL-1β in each intestinal segment of mice as indicators; LC-MS/MS was used to analyze the composition changes of the 95% alcohol extract of EPR before and after milk processing.

  RESULTS  Compared with the blank group, the raw and water processed products of EPR could significantly increase the water content of mouse feces and the levels of TNF-α and IL-1β in each intestinal segment (P < 0.05); compared with the raw product group, all indicators in the milk processing group were significantly reduced (P < 0.05), while there was no significant difference in the water processing group, indicating that water processing cannot attenuate toxicity, and the auxiliary material milk is the key auxiliary material to reduce the toxicity of EPR. Mass spectrometry analysis results showed that a total of 50 components were identified in EPR, including 38 terpenoid components, 6 phenolic acid components, and 6 other components. The content of each component decreased to varying degrees after milk processing. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were performed on the mass spectrum data of raw materials and products, and it was found that the components of raw materials and products can be obviously clustered into 2 categories. 13 differential components of raw materials and products were screened through t test, and 11 of which were terpene components, indicating that the composition of terpene components changed significantly after milk processing. 17 components derived from EPR were detected in the residual liquid of milk excipients after processing, of which 16 were terpenoids, indicating that the terpenoid components of EPR were transferred to the excipient milk during the soaking and processing processes.

  CONCLUSION  The toxicity of EPR is reduced and the purgative effect is alleviated after milk processing. The attenuation mechanism may be that during the milk soaking and processing processes, terpenoid components are transferred to the milk, and the content of toxic components in the decoction pieces is reduced, thereby reducing the toxicity.