Quantitative determination of nine xanthones in Polygala caudata and fingerprinting of Polygala L by HPLC

A facile method, based on high performance liquid chromatography (HPLC) with diode array detection (DAD), was developed for the simultaneous quantitative determination of nine xanthones in the root of Polygala caudata Rehd. et Wils., a Chinese folk medicinal herb. The HPLC fingerprint of xanthones was developed for the first time and applied to assess the quality of related Polygala medicinal plants. Ultrasonic extraction with chloroform-methanol (982) gave good yields of nine xanthone standards, the average recovery rates ranged from 94.1 to 113.4% (n=5). The relative standard deviation (RSD) values for reproducibility were between 2.21 and 9.21% (n=5). The fingerprint chromatograms of P. tenuifolia Wild. from six different planting regions were analyzed to set up a simulative mean chromatogram with 11 common peaks. The software of Similarity Evaluation System for Chromatographic Fingerprint of TCM (2004A version), developed by Chinese Pharmacopoeia Commission, was applied for data processing. The correlation coefficients of each chromatogram to the simulative mean chromatogram of P. tenuifolia were within the range of 0.8070.927, and the correlation coefficients between each chromatogram were 0.6890.907. The method can be used for the quality evaluation and control of Radix Polygalae, and provide a possibility for identifying the Polygala species rapidly.