Quality evaluation of various commercial specifications of Polygoni Multiflori Radix and its dregs by determination of active compounds

BACKGROUND: According to market investigation, two kinds of Polygoni Multiflori Radix decoction pieces with different specifications are commercially available: irregular thick slices (0.7-1.3 cm) and length-wise into thin slices (0.11-0.2 cm). The objective of this study was to evaluate the quality of various samples of Polygoni Multiflori Radix decoction pieces and its dregs. RESULTS: A simple and reliable high performance liquid chromatographic method was developed for determination the contents of 2,3,5,4'-tetrahydroxystilbene-2-O-β-D- glucopyranoside (THSG), emodin and physcion, which were considered to be potent active ingredients. The results showed that the contents of THSG, emodin and physcion varied in samples of different diameters and thicknesses. The results also indicated the dregs of Polygoni Multiflori Radix still contained a considerable amount of THSG, emodin and physcion. CONCLUSION: The various commercial specifications of Polygoni Multiflori Radix sold in the markets did not correlate with their prices, and the dregs of Polygoni Multiflori Radix can be further utilized.