Identification of Chemical Constituents and Pharmacokinetics of Differential Phytochemicals in Crude and Salt-Processed Plantago asiatica L. by UHPLC-Q-TOF-MS

Plantaginis semen (PS), a traditional herbal medicine extensively utilized in China, contains bioactive compounds that exhibit notable therapeutic effects in promoting diuresis, regulating blood pressure, modulating lipid metabolism, and controlling blood glucose levels. Crude PS (CPS) and salt-processed CPS (SPS) are the two most commonly used decoction pieces of PS. The therapeutic efficacy of PS is further enhanced after salt processing, resulting in the SPS exhibiting superior pharmacological effects compared to the CPS. This study aims to explore the differences in chemical constituents between CPS and SPS in vitro. Additionally, the study seeks to compare the pharmacokinetics (PKs) of bioactive compounds after oral administration of extracts from both crude and salt-processed PS in rats. The identification results showed that there were 45 common components and six unique components between CPS extract and SPS extract. The results of multivariate statistical analysis have identified six differential components. The PK study results demonstrated that the mean plasma concentration–time profile and PK parameters of six representative components were significantly different between CPS extract and SPS extract. This study proved that salt-processed method increased the dissolution of most components and absorption of active components in PS, and revealed the material basis underlying the superior efficacy of SPS compared to CPS to some extent. This study provides a scientific foundation for the enhanced therapeutic efficacy of traditional Chinese medicine (TCM) following salt processing, elucidating how this ancient preparation method amplifies pharmacological activity through modern mechanistic insights.