Isolation and establishment of Physcion as a chemical reference substance from radix Polygonum multiflorum thunb.

Abstract

Polygonum multiflorum (Family: Polygonaceae) is a precious medicinal species listed in the IUCN Red Book of Vietnam and needed to be protected. Radix Polygonum multiflorum has been widely used in traditional Vietnamese and Chinese medicines and it is consequently utilised in a great demand. However, to guarantee the quality of medicinal herbs in the market, they are required to have the pharmacopoeial testing and control in general. One of methods used to achieve accurately analytical results is the use of chemical reference substances. Chemical reference substances isolated from natural sources are important materials that are used to verify the quality and trace analysis of medicinal products containing medicinal plants. In Vietnam, there have been any reference standard compounds for the quality control of Polygonum multiflorum. This paper reported the isolation of physcion from Radix Polygonum multiflorum Thunb. which was subsequently established as a reference substance. The isolation was performed using column chromatography on silica gel with different eluents. The compound purity and quality determination were validated by infrared spectroscopy (IR), ultraviolet (UV), nuclear magnetic resonance (NMR) and high-performance liquid chromatography (HPLC). In addition, the compound was evaluated for the homogeneity and assigned value to establish as the reference substance based on the standards of TCVN ISO 17034:2017, Appendix 3 of World Health Organization (WHO technical series 943:2006) and statistical methods for use in proficiency testing by inter-laboratory comparison ISO 13528:2015.