Ephedrae herba has been used in traditional Chinese and Japanese (Kampo) medicine from ancient times, with the primary resource being in China. In the present study, a field survey as well as molecular and chemical assessments were conducted on Ephedra plants in Mongolia to clarify whether they could be an alternative resource of the Ephedrae herba used in Japanese Kampo medicine. Ephedra sinica, E. equisetina, E. przewalskii, E. regeliana, E. monosperma and an unknown taxon (ESP) collected in Mongolia were divided into 9 genotypes on the basis of nucleotide sequences of 18S ribosomal RNA (rRNA) gene and trnK gene. E. sinica, E. equisetina, and E. monosperma presented completely identical sequences to the corresponding species from China. The sequences of trnK gene and 18S rRNA gene provide a useful index for identification and taxonomic classification of Mongolian Ephedra plants. Quantitative analysis of 5 ephedrine alkaloids revealed that almost all Mongolian Ephedra plants contained high amounts of total ephedrine alkaloids (TAs, 1.86-4.90%) and a high percentage of pseudoephedrine in TAs differed obviously from the Chinese. E. sinica and E. equisetina found in eastern and central Mongolia, showing total contents of ephedrine and pseudoephedrine higher than 1.43%, were potential new resources of Japanese Pharmacopoeia grade Ephedrae herba.Key words Ephedra; Mongolia; molecular identification; ephedrine alkaloid; HPLC analysis Biol. Pharm. Bull. 32(7) 1235-1243 (2009) © 2009 Pharmaceutical Society of Japan * To whom correspondence should be addressed. e-mail: katsukok@inm.u-toyama.ac.jp present study, we determined the nucleotide sequences of these two regions and compared them with 8 clearly identified Chinese Ephedra plants for objective identification and to aid in the taxonomic resolution of Ephedra plants in Mongolia. In addition, clarification of the chemical equality of Mongolian Ephedra plants and the available Ephedrae herba is needed, because the constitutions of ephedrine alkaloids differ among species and there are also some species without these alkaloids.2) Subsequently, quantitative analysis on five major ephedrine alkaloids was conducted by HPLC-photodiode array detector (PDA) method for quality evaluation. lia showed curved or twisted stems and some had allopheric features as shown in Fig. 2. Here, we tentatively treated these samples as Ephedra sp. (ESP) and included all of them in the following molecular and chemical analyses. It is noteworthy that due to fewer morphological characteristics being available in "Flora of Mongolia" 11) and the "Key to the vascular plants of Mongolia," 12) floristic literature with valuable morphological information on Ephedra plants of neighboring regions were used as reference in morphological identification, such as "Flora Xinjiangensis," MATERIALS AND METHODS Materials19) "Flora of China" and "Flora of Siberia." 20) All the vouchers and samples from Mongolia are stored in the Museum of Materia Medica, Institute of Natural Medicine, University of Toyama...

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Strong evidence against stability of the negative ion of ytterbium is presented, and the prediction is made that the lowest negative ion state Yb − 4f 14 6s 2 6p 2 P 1/2 is a narrow shape resonance in the electron-atom continuum at 20 meV. These results are obtained from the many-body theory calculations with the electron-atom correlation potential appropriately scaled to reproduce the experimental data for the isoelectronic neutral Lu and Ba − . They are in agreement with the recent thorough experimental investigation of Yb − by the Aarhus group.