Objective To study the chemical constituents of the acid hydrolytic products from the stems and leaves of Panax quinquefolium. Methods The stems and leaves of P. quinquefolium were hydrolyzed with acid;Isolation and purification were carried out by various chromatographic techniques,such as silica gel and so on. Compounds were identified and elucidated by spectral and chemical methods. Results Eight compounds were obtained from the acid hydrolytic products in the stems and leaves of P. quinquefolium and identified as 20 (S)-panaxadiol (Ⅰ),20 (S)-protopanaxadiol (Ⅱ),20 (R)-protopanaxadiol (Ⅲ),20 (S)-panaxatriol (Ⅳ),24 (R)-ocotillol (Ⅴ),20 (R)-protopanaxatriol (Ⅵ),20 (R)-dammarane-3?,12?,20,25-tetrol (Ⅶ),and 20 (R)-dammarane-3?,6?,12?,20,25-pentol (Ⅷ). Conclusion Compounds Ⅰ-Ⅷ are the derivates of the aglycones of ginsenosides,isolated from the acid hydrolytic products from the stems and leaves of P. quinquefolium for the first time. Among these compounds,Ⅳ,Ⅶ,and Ⅷ are discoverd from the roots,stems,leaves,fruits,and buds of P. quinquefolium for the first time. Compound Ⅶ is discovered and reported that it is the derivate of the aglycone of protopanoxadiol ginsenoside,with the conspicuous anticancer activity from the fruits of P. ginseng for the first time.

Objective To study the anti-depression mechanism of Dingzhixiaowan concerning on histology of hippocampal formation.Methods 40 female rats were divided into control,depression model group(model group),distilled water group(DW group) and Dingzhixiaowan group(Chinese herb group).Behavior points were measured by open field method.Serum concentrations of cortisol and estradiol(E2) were checked with ELISA.HE staining and electron microscopy were applied to observe the histology of neurons in hippocampal formation.Immunohistochemistry method was employed to detect Nestin expression.Results Compared with the control,behavior points,serum E2 level and Nestin expression decreased obviously and serum cortisol level increased markedly,CA3 neurons were seriously damaged in model and DW groups.While behavior points,serum E2 level did not change,Nestin expression increased obviously and serum cortisol level decreased markedly,CA3 neurons were basically normal in Chinese herb groups.Conclusion Dingzhixiaowan can protect hippocampal formation,which might be one of the anti-depression mechnisms.