ABSTRACT
Objective: To study the correlation between the content changes of main medicinal ingredients and the color values of Rhei Radix et Rhizoma during storage based on the principle of chromaticity analysis,and to provide reference for studying on the mechanism of discoloration and improving the quality evaluation of Rhei Radix et Rhizoma. Method: Simulated accelerated test was adopted in this study, where Rhei Radix et Rhizoma was stored under high temperature(40±5)℃,high humidity RH(92.5±5)%and strong light(4 000±500)Lx conditions to accelerate its discoloration. For the samples taken at different time points,the color value was determined by spectrophotometer and the total contents of anthraquinone and free anthraquinones,sennoside A,B,catechin and gallic acid were determined by high performance liquid chromatography (HPLC). The correlation between the effective components and the color value of rhubarb was analyzed by SPSS software. Result: During the storage process,it was observed by the eye that the color of Rhei Radix et Rhizoma was significantly darker and darker in the simulated acceleration test. According to the analysis of the chromaticity value results,the changes of chromaticity values L*and E*ab of Rhei Radix et Rhizoma were significantly negatively correlated with free strontium content(PPa* was significantly negatively correlated with gallic acid(PPConclusion: There is a certain correlation between the change of color value and the content of six medicinal ingredients during Rhei Radix et Rhizoma storage.