QUALITY CONTROL OF POLYGONUM CUSPIDATUM BY UPLC-PDA AND RELATED STATISTICAL ANALYSIS

A rapid and accurate ultra-performance liquid chromatography-photo-diode array (UPLC-PDA) detection method was established for simultaneous determination of 5 compounds including polydatin, resveratrol, emodin-8-glucoside, emodin, and physcion in Polygonum cuspidatum. Twenty-six batches of samples were collected from different areas and markets in China. The compounds were separated in less than 12min using a C18 column with acetonitrile and water containing 0.5% acetic acid as the mobile phase at a flow rate of 0.3mL/min. The precision (intra-day and inter-day assay), stability, limits of detection and quantitation, linearity, and recovery were evaluated for this method. RSD for intra-day precision, inter-day precision, and stability were less than 2.5%, 3.5%, and 2.19%, respectively. Recovery ranged from 96.78% to 104.58% (RSD<2.71%). The content range of polydatin, resveratrol, emodin-8-glucoside, emodin, and physcion were 13.45-34.55, 0.97-13.12, 3.34-17.62, 6.53-13.69, and 1.71-4.23mg/g, respectively. By applying principal component analysis and hierarchical cluster analysis, the quality of 26 specimens can be divided into 3 groups according to contents of compounds. This indicates the need to strengthen the quality control of P. cuspidatum. This is the first report to provide an effective UPLC method and related statistical methods to evaluate the quality of P. cuspidatum from different areas.