Quality differentiation of Epimedium from different harvesting periods based on LC-MS and network pharmacology

Abstract

Epimedium is an essential genus of homologous plants used as medicine and food, which has various pharmacological effects and great utilization value in the market. Currently, research into the quality of Epimedium focuses mainly on species and region identification. However, the harvesting period also influences the quality of Epimedium; this aspect requires further study. In this paper, a systematic method is developed based on high-performance liquid chromatography (HPLC) fingerprint analysis, chemometrics, and network pharmacology methods to compare the quality of Epimedium from two harvest periods. A method is developed using liquid chromatography–mass spectrometry (LC-MS) to identify fingerprint peaks. Chemical composition analysis is performed using cluster analysis and orthogonal partial least squares discriminant analysis (OPLS-DA). Ultimately, network pharmacology analysis is employed to forecast the potential effects of compounds associated with standard chromatographic peaks. The fingerprint peaks were identified through LC-MS and corroborated with references. Subsequently, chemometric analysis revealed a distinct division between the HPLC fingerprints of samples from the two harvest periods. This was accomplished by employing cluster analysis and OPLS-DA. Additionally, utilizing the variable impact projection (VIP) obtained from OPLS-DA, a total of seven compounds exhibiting quality discrepancies were identified. Lastly, the network pharmacology analysis indicated that compounds corresponding to typical chromatographic peaks demonstrate therapeutic effects on osteoporosis. Moreover, primary bioactive compounds are identified through degree value screening. This approach is powerful for the quality assessment of Epimedium from different harvesting periods and can also be extensively applied for the quality control of other herbal materials.