Cynanchum otophyllum Schneid (Chinese name Qingyangshen) is a folk medicinal plant endemic to Yunnan Province of China, whose root was used for the treatment of epilepsy, rheumatic pain, kidney weakness, and muscle injures by local people. Based on the chemical and pharmacological experiments in 1980s, it has been developed as an anti-epilepsy remedy and put into industrial production for many years in China. The effective ingredients are C-21 steroidal glycosides named otophyllosides with qingyangshengenin and caudatin as aglycones. However, the quality of this phytomedicine was not so stable these years because of the confusion of its original plant materials.

Zhang Yinjun’s group studied on the roots of C. otophyllum collected in the northwest of Yunnan Province, which led to the isolation of fifteen C-21 steroidal glycosides, including twelve new ones. These glycosides had qingyangshengenin or caudatin as aglycones and 3 to 7 sugar units composing of cymarose, oleandrose, digitoxose, thevetose, and glucose as saccharide moieties. A HPLC analytical method was established for the quality control of the medicinal materials. It is revealed that various botanical materials called Qingyangshen by the local people contained different constituents. One of them even had no qingyangshengenin or caudatin by further HPLC analysis of their total aglycones, suggesting that it should not be used as the raw material.

The results have been reported by two publications in Steroid (2011, 76 (10-11):1003-1009; 2007, 72 (11-12): 778-786.), which enriched the molecular diversity of C21 steroids, and provided information in further understanding of chemical composition and activity of C. otophyllum from different location. (image by KIB)

http://www.sciencedirect.com/science/article/pii/S0039128X11001292