Correlation Between Color and Contents of Water and 5-Hydroxymethylfurfural in Ginseng Radix et Rhizoma Rubra / 中国实验方剂学杂志

ABSTRACT

Objective:To explore the correlation between colors and contents of water and 5-hydroxymethylfurfural (5-HMF) in Ginseng Radix et Rhizoma Rubra (GRRR). Method:The colors were observed under sunlight on a sheet of white paper. The chroma value and color difference were determined and calculated by a colorimeter. Water content was determined by the oven-drying method. An HPLC method was established and used to determine the content of 5-HMF. The correlation was analyzed by the Spearman and Pearson analysis. Result:The colors of GRRR were yellowish-white,ocher-yellow,and yellowish-brown. The values of L*,a*,b*,and ΔE* had a certain range, and could reflect the colors of GRRR. The content of water ranged from 4.01%to 8.31%and was in accordance with the requirement the Chinese Pharmacopoeia. The content of 5-HMF ranged from below the limit of detection (1.985×10-4 μg) to 78.97 μg·g-1. The results of correlation analysis shows significant correlations between L*,a*,b*, ΔE* values and water content, that is to say,the deeper the color was, the higher the content of water was,but with no significant correlation with 5-HMF content. Conclusion:The color of processed GRRR was related to water content but not related to 5-HMF content,which was not consistent with the correlation between color and 5-HMF content that generally existed in a series of raw Chinese medicinal materials. It indicated an essential difference between the color shade of processed Chinese medicinal materials and the cause of color change of raw Chinese medicinal materials. Therefore,it was significant to control water content for ensuring the stability of GRRR. This study determined the colors of GRRR by a colorimeter, systematically determined 5-HMF content,and proposed the effect of water contents on the color of GRRR.