Combination of stable isotopes and multi-elements analysis with chemometric for determining the geographical origins of Rhizoma Coptidis

•A novel analysis method based on elemental and isotopic analysis combined with chemometric technique was established for discriminating the origins of Rhizoma Coptidis.•The Rhizoma Coptidis from different areas were successfully discriminated.•The models for discriminating the origins of Rhizoma Coptidis were established.•The candidate discriminant markers for the determination of origins were found. Rhizoma Coptidis is a valuable medicine food homology plant, whose geographic origin is a topic of interest to both consumers and producers since the geographic origin determines its prices and efficacy. A novel method for discriminating the geographic origins of Rhizoma Coptidis was established based on stable isotopes and multi-elements analysis combined with chemometric. Then, 4 light stable isotope ratios and 32 inorganic elements of 103 samples from six regions were determined. The results showed that the isotopes ratios and multi-elements contents were significantly different among Rhizoma Coptidis from six regions. Al, Sn, Mg, δ15N and δ13C (VIP > 1.5) were considered as the most powerful differentiation markers for discriminating the geographical origins. In addition, by linear discriminant analysis (LDA) and orthogonal partial least squares discriminant analysis (OPLS-DA), all samples were successfully classified with 100% accuracy. Based on the built predictive model, the origin of unknown samples were successfully predicted with 100% accuracy. The parameters of the models R2X, R2Y and Q2 were 0.999, 0.900 and 0.854, respectively. Therefore, the stable isotopes and multi-elements analysis combined with chemometric tools can be successfully used to discriminate the geographic origins of Rhizoma Coptidis.