Cynanchum stauntonii

Yang et al. (2005) stndied the anti-influenza virus activities of the volatile oil from the roots of the Asclepiadaceae Cynanchum stauntonii and found that the volatile oil caused an antiviral effect against influenza virus in vitro and also in in vivo experiments and was able to prevent the number of deaths induced by the virus in a dose-dependent manner. 

Yang, Z.-C., B.-C. Wang, X.-S. Yang, and Q. Wang, 2005. Chemical composition of the volatile oil from Cynanchum stauntonii and its activities of anti-influenza virus. Biointerfaces, 43(3 ) 198-202. 

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