Correlation Analysis Between Material Basis and Color Characteristics of Polygoni Multiflori Radix Decoction Pieces During Ancient Classical Nine-time Repeating Steaming and Sun-drying Processing / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo analyze the dynamic changes of the main chemical components and color characteristics of Polygoni Multiflori Radix（PMR） during the process of ancient classical nine-time repeating steaming and sun-drying， and to explore the correlation between the changes. MethodHigh performance liquid chromatography（HPLC） was used to determine the contents of gallic acid， stilbene glycoside， emodin-8-O-β-D-glucoside， physcion-8-O-β-D-glucoside， emodin and physcion in PMR during the process of nine-time repeating steaming and sun-drying， and electronic eye technology was used to objectively characterize the color of PMR during the process. Partial least squares（PLS） was used to analyze the correlation between the content of main components and the color characteristics. ResultDuring the nine-time repeating steaming and sun-drying process of PMR， the content of gallic acid gradually increased with the increase of steaming and sun-drying times， and the contents of other components showed fluctuating changes， with an overall decreasing trend in the contents of stilbene glycoside， emodin-8-O-β-D-glucoside and physcion-8-O-β-D-glucoside， and an overall increasing trend in the contents of emodin and physcion. The results of electronic eye analysis showed that the color of PMR became dark， red and blue in the process of nine-time repeating steaming and sun-drying. The results of hierarchical cluster analysis（HCA） and principal component analysis（PCA） of the contents of six main components and the colors showed that the samples steamed and sun-dried for one to four times could be grouped into one category， the other five categories of samples could be grouped into another category. Gallic acid and stilbene glycoside were significantly correlated with the color indexes of PMR during the process of nine-time repeating steaming and sun-drying. ConclusionThe general changes of material basis and color characteristics of PMR during the process of ancient classical nine-time repeating steaming and sun-drying have certain rules， and the establishment of the correlation model between color and index components can realize the judgment and quality evaluation of processing degree of PMR decoction pieces.