Abstract: From the rhizome of Panax japonicus C. A. Meyer var major (Burk.) Wu et Feng, collected in Qinling Mountain (Shaanxi), seven saponins were isolated. By means of 13C NMR, FAB-MS and comparison with authentic samples, six of them were identified with chikusetsusaponin Ⅴ (=ginsenoside Ro), Ⅳa, oleanolic acid 28-O-β-D-glucoside, ginsenoside Re, Rg2 and notoginsenoside R2. Another saponin was proved to be chikusetsusaponin Ⅳa methylester, and its structure was elucidated to be oleanolic acid (3-O-β-D-glucorunopyranosyl-methylate)-28-O-β-D-glucopyranoside. A comparison of sapoinin constituents of this variety collected in Qinling Mountain (Shaanxi) and Hengduan Mountains (Yunnan) was provided. As a common characteristic of both rhizome, it has been proved that the saponins of oleanane type were main constituents and the saponins of dammarane type were minor constituents. But some differences also has been found in both materials (Tab. 1). From the relationship between the biosynthesis pathway of triterpenoids and plant phytogenetics, this is a phenomenon of chemical polymorphism in a variety, which followed in the train of geographical distribution, ledto appearance of a che- mical evolution in the process of evolution and of spread of this variety.

Key words: Panax japonicus var. major, Triterpenoid saponins, Chikusetsusaponin Ⅳa methy lester