Constituent properties of licorices derived from Glycyrrhiza uralensis, G. glabra, or G. inflata identified by genetic information

Abstract

Constituent properties of licorices derived from Glycyrrhiza uralensis, G. glabra, and G. inflata are revealed by comparing 117 of licorice identified using four genetic markers; internal tracscribed spacer (ITS) on nuclear ribosomal DNA, rbcL gene, matK gene, and trnH-trnK1 intergenic region on chloroplast DNA. Regarding six main constituents of licorice; glycyrrhizin, liquiritin, liquiritin apioside, isoliquiritin, isoliquiritin apioside, and liquiritigenin, the constituent property of G. glabra resembles to that of G. inflata. On the other hand, the constituent property of G. uralensis is not similar to that of G. glabra or G. inflata and is characterized by a wide content variation of the six constituents compared to those of G. glabra and/or G. inflata. The mean contents of liquiritin, isoliquiritin, or liquilitigenin in G. uralensis are significantly higher than those of G. glabra or G. inflata. Therefore, the licorice species should be selected depending on these constituent properties for the traditional Chinese medicines or the Japanese Kampo medicines. Additionally, glycycoumarin, glabridin, and licochalcone A were reconfirmed as the species-specific typical constituents of G. uralensis, G. glabra, and G. inflata respectively. Therefore, it is resulted that the determination of the three species-specific constituents may be useful for the species identification of licorice. However, since 6% of licorice examined and hybrids were exceptions to the rule, their genetic information is necessary for the accurate species identification of licorice.