3,5-Nonadiyne isolated from the rhizome of Cachrys ferulacea inhibits endogenous nitric oxide release by rat peritoneal macrophages.

3,5-Nonadiyne, in vitro, selectively inhibits endogenous nitric oxide release (IC(50)=6.7+/-0.8 microM) by rat peritoneal macrophages at doses that do not inhibit T cell proliferation. 3,5-Nonadiyne was isolated from root essential oil of Cachrys ferulacea (L.) CALESTANI, synonym Prangos ferulacea (L.) LINDLEY, obtained by hydrodistillation and spectrometricaly identified unambiguously.