Quality assessment of Polygonum cuspidatum and Polygonum multiflorum by 1H NMR metabolite fingerprinting and profiling analysis.

The quality assessment and control of traditional Chinese medicines (TCM) nowadays receives a great deal of attention worldwide and particularly in Europe with its increasing local use. Polygonum cuspidatum Siebold & Zucc. and Polygonum multiflorum Thunb. are two members of the Polygonaceae family, which are widely used as Chinese medicinal plants. The aim of this study was to achieve an overview of the quality of P. cuspidatum and P. multiflorum samples available on the Chinese market and to identify important metabolites for their discrimination, using (1)H NMR-based metabolomics. (1)H NMR and multivariate analysis techniques were applied to almost 60 plant samples collected in different places in China. Using (1)H NMR metabolomics, it was possible, without previous evaporation or separation steps, to obtain metabolic fingerprints to distinguish between the species. The important metabolites for discrimination were stilbene derivatives. Finally, a clear distinction between the two species was possible and the discriminant metabolites were identified.