Simultaneous qualitative and quantitative analysis of commercial bistorta rhizome and its differentiation from closely related herbs using TLC and HPLC-DAD fingerprinting.

A qualitative and quantitative analysis method was established to improve quality assessment standards for Rhizoma Polygoni Bistortae (Polygonum bistorta L.) and differentiate commercial bistorta rhizome from closely related herbs by TLC and HPLC-DAD fingerprinting. Three compounds including phenolic acid and flavane were identified by comparison with standard compounds and quantified simultaneously by HPLC-DAD simultaneously. A comprehensive validation of the method that included sensitivity, linearity, repeatability and recovery was conducted. Paris polyphylla SM., a herb often mixed with Polygonum bistorta L. in China due to their same popular name "Caoheche" in history, was successfully distinguished by thin-layer chromatography (TLC) fingerprinting of the petroleum-soluble fraction. Polygonum paleaceum WALL., another herb often mixed with Polygonum bistorta L. due to their similar external appearances, was distinguished by HPLC fingerprinting.