Context: Rhizoma coptidis is a broadly used traditional Chinese medicine (TCM). The investigation of the influence of species and geographical origins on the phytochemicals of R. coptidis is crucial for its reasonable application and quality control.
Objective: Development of an effective method to systematically study the phytochemical variations of the rhizomes of three Coptis species (Ranunculaceae) (Coptis chinensis Franch, Coptis deltoidea C.Y. Cheng et Hsiao and Coptis teeta Wall.) and a species (i.e., C. chinensis) obtained from both Daodi and non-Daodi production regions.
Results: The three species had significant differences in their phytochemicals. The rhizome of C. chinensis contained more epiberberine (13.52 ± 2.65 mg/g), palmatine (18.20 ± 2.89 mg/g), coptisine (23.32 ± 4.27 mg/g) and columbamine (4.89 ± 1.16 mg/g), whereas the rhizomes of C. deltoidea and C. teeta showed the highest level of jatrorrhizine (8.52 ± 1.36 mg/g) and berberine (81.06 ± 4.83 mg/g), respectively. Moreover, the rhizome of C. chinensis from three Daodi production regions (Shizhu, Lichuan and Emeishan) contained more alkaloids than those from three non-Daodi production regions (Mianyang, Shifang and Zhenping).
Discussion and conclusion: It is necessary to use the three R. coptidis species differentially in TCM clinical practice. Daodi C. chinensis medicinal materials have better quality than most non-Daodi ones, and so they should be preferred for TCM prescription. The combination of HPLC-based fingerprint analysis and quantification of multi-ingredients with statistical analysis provided an effective approach for species discrimination and quality evaluation of R. coptidis.
Keywords: Daodi medicinal materials; High-performance liquid chromatography; alkaloids; quality control; species differentiation.