ABSTRACT
OBJECTIVE: To study the correlation between the color of Moutan Cortex and the contents of effective components before and after carbonized, and to provide reference for identification and quality evaluation of Moutan Cortex and its charcoal piece decoction. METHODS: Using colorimeter determination of Moutan Cortex and Moutan Cortex charcoal decoction pieces powder chroma space parameter [lightness value (L*), red, green and component values (a*), yellow and blue component value (b*) and total color difference value (E*ab)], HPLC method for content determination of 10 effective components (gallic acid, 5-HMF, catechins, oxypaeoniflorin, paeoniflorin, quercetin, benzoyl paeoniflorin, isorhamnetin, paeonol, kaempferide) content in Moutan Cortex and Moutan Cortex charcoal decoction pieces. On this basis, the correlation between the content of effective components and the chromaticity space parameter of a color was studied by SPSS 21.0 software. RESULTS: There was no correlation between gallic acid content and the chromaticity space parameter of a color (P>0.05). There was an extremely significant negative correlation between 5-HMF content and L*, b*, E*ab (P<0.01), and an extremely significant positive correlation between 5-HMF content and a* (P<0.01). The content of paeoniflorin was positively correlated with L*, b* and E*ab, but not with a* (P>0.05). The content of oxidized paeoniflorin was positively correlated with L* and E*ab (P<0.01), and negatively correlated with a* (P<0.01), but not with b* (P>0.05). The content of catechins, quercetin, benzoyl paeoniflorin, isorhamnin, paeonol and kaempferol were positively correlated with L*, b* and E*ab (P>0.05), and negatively correlated with a* (P>0.05). CONCLUSIONS: Chromatic aberration technology can quantify the color of Moutan Cortex and its charcoal decoction pieces, and there is a significant correlation between the color of Moutan Cortex before and after processing and the content of its active ingredients.