Correlation Analysis on Cross Section Color of Licorice and Its Active Ingredients / 世界科学技术-中医药现代化

ABSTRACT

This study was aimed to establish an objective and convenient method to evaluate the quality of licorice through the study on correlation between the cross section color and contents of active ingredients of licorice.Therefore,colorimeter was introduced and applied to determinate cross section color of licorice.Meanwhile,contents of five active ingredients of licorice were also determined.HPLC was used to determine liquiritin and glycyrrhizic acid.Colorimetric method was used to determine total saponins.Ultraviolet spectrophotometry was used to determine total flavonoids.Sulphuric acid-phenol colorimetry was used to determine polysaccharides.Correlation between the cross section color and content determination result was analyzed.The results showed that the correlation coefficient of glycyrrhizic acid content and L* was-0.578,P ＜ 0.001,the correlation coefficient with b* was 0.596,P ＜ 0.001;the correlation coefficient of liquiritin content and L* was-0.503,P =0.002,the correlation coefficient with b* was 0.890,P ＜ 0.001;the correlation coefficient of total flavonoids content and L* was-0.729,P ＜ 0.001,the correlation coefficient with b* was 0.724,P ＜ 0.001;the correlation coefficient of polysaccharides content and L* was 0.230,P =0.190,the correlation coefficient with b* was-0.390,P =0.023;the correlation coefficient of total saponins content and L* was-0.411,P =0.016,the correlation coefficient with b* was 0.738,P ＜ 0.001.It was concluded that the cross section color index of licorice has significant correlation with contents of glycyrrhizic acid,liquiritin,total flavonoids and total saponins.There was no significant correlation with content of polysaccharides.It illustrated the close correlation between cross section color of licorice and its active ingredients.Through the digitalized determination on color,contents of chemical composition in licorice can be initially determined or predicted objectively.It provided a new idea and method for the quality evaluation of Chinese herbal medicine.