UPLC-Q TOF-MS-Based metabolomics and anti-myocardial ischemia activity of Dioscoreae Nipponicae Rhizoma from different geographical origins

The dried rhizome of Dioscorea nipponica Makino (“Chuanshanlong” in Chinese) is a medicinal herb with multiple major producing areas. The main objective of this study was the comparative profiling of Dioscoreae Nipponicae Rhizoma (DNR) from various geographical origins. A hypoxia/reoxygenation-induced H9c2 cell injury model was established, and the antimyocardial ischemia activity of DNR samples from different origins was detected using the cell counting kit-8 (CCK-8) method. The result showed that the antimyocardial ischemia potential of DNR samples from the Heilongjiang province was higher than that of the other studied samples. Subsequently, a plant metabolomics technique utilizing ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q TOF-MS) was used to determine the differences in DNR samples from various geographical origins. Forty compounds, including steroidal saponins, free fatty acids, and organic acids, were tentatively identified based on UPLC-Q TOF-MS fragmentation pathways and via comparison with available reference standards. Partial least squares discriminant analysis was performed to estimate the differences in DNR samples from different origins. Five compounds were significantly up-regulated and correlated with antimyocardial ischemia in DNR samples from Heilongjiang province. Molecular docking was used to discern the interactions of key markers with the active sites of the target protein. The findings signified that UPLC-Q TOF-MS metabolomics coupled with molecular docking is a powerful tool to rapidly identify the quality control characteristics of DNR samples and their products. The research provides a direction for the rational utilization of DNR.