Pharmaceutical evaluation of Glycyrrhiza uralensis roots cultivated in eastern Nei-Meng-Gu of China.

To clarify the feasibility of medicinal use of the cultivated Glycyrrhiza resources, the equivalency between the G. uralensis roots cultivated in eastern Nei-Meng-Gu of China and medicinal licorice (Glycyrrhizae Radix, Gancao in Chinese and Kanzo in Japanese) was examined. The HPLC fingerprint including glycyrrhizin (GL) of the cultivated roots was similar to that of medicinal Gancao, but different from that of non-medicinal Xinjiang-Gancao (Shinkyo Kanzo in Japanese). Similarity between the cultivated roots and two medicinal Gancao was confirmed quantitatively by hierarchical cluster analysis on the basis of HPLC-7-peak-area data. Moreover, the 4-year-old adventitious roots conformed to the five standards described in the Japanese Pharmacopoeia XIV (JP XIV). The 4-year-old adventitious roots had similar pharmaceutical properties to those of medicinal Dongbei-Gancao (Tohoku Kanzo in Japanese) as determined by examining IgE-mediated triphasic skin reaction in mice and pharmacokinetic profile of glycyrrhetic acid, an anti-allergic metabolite of GL. The present pharmaceutical study suggests that the 4-year-old adventitious roots of G. uralensis cultivated in eastern Nei-Meng-Gu of China are comparable to medicinal Gancao conforming to the JP XIV, and may be a potential medicinal source to compensate for the insufficiency of wild Glycyrrhiza plants caused by collection restriction in China.