Comprehensive quality evaluation of Codonopsis Radix using HPLC fingerprinting, quantitative analysis, and chemometrics analysis

Abstract

Codonopsis Radix (CR), a traditional Chinese medicine with significant medicinal value, has been widely used for many years. In this study, a comprehensive quality evaluation system for CR from different regions was established using high-performance liquid chromatography (HPLC). First, the optimal extraction conditions for two glycoside components from CR were determined through response surface methodology, with the following parameters: a methanol ratio of 80%, an extraction time of 35 min, and a liquid-to-solid ratio of 50 : 1. This optimized extraction method was applied to both fingerprinting and quantitative analysis. In the quantitative analysis, the calibration curves exhibited excellent linearity (R² ≥ 0.9998) within the tested range, and the mean recoveries ranged from 99.46% to 101.51%. A common fingerprint, consisting of 13 characteristic peaks, was established for CR samples from different production areas in China. HPLC-DAD-ESI-MS/MS was used to further identify the common peaks in the fingerprint. Various chemometrics analyses, including similarity analysis (SA), hierarchical cluster analysis (HCA), principal component analysis (PCA), and orthogonal partial least squares discriminant analysis (OPLS-DA), were employed to classify the samples. Among these methods, OPLS-DA was particularly effective in distinguishing CR samples of different plant sources. The results demonstrate that the established method is effective for the comprehensive quality evaluation of CR, providing a reliable approach for its quality control and standardization.