Aphrodisiac Principles and other Constituents from the Roots of Panax quinguefolium and Panax ginseng .

Bioassay-guided fractionation of P. quinquefolium and P. ginseng root extracts afforded six compounds. Among these, two bioactive compounds ginsenoside Re ( 1 ) and (20 S )-ginsenoside Rg2 ( 5 ) exhibiting significant relaxation in rabbit corpus cavernosum with EC 50 values of 95.1 and 114.7 μM, respectively. In addition, the phytochemical composition of the water extract of the roots of P. quinquefolium was investigated, and thirty-one compounds were characterized, including four undescribed compounds panajaponol B ( 18 ) and panaxjapynes D-F ( 21 - 23 ). Moreover, the spectral characteristics and biosynthetic pathway of Panax triterpene saponins were discussed according to our results and some previous reports.