Monoterpenoids from the Fruits of Have Inhibitory Effects on Nitric Oxide Production.

In our search for novel plant-derived inhibitors of nitric oxide (NO) with potential for treating inflammatory diseases, the phytochemicals of fruits were investigated, leading to the isolation of one bicyclic nonane (), three menthene skeleton monoterpenoids (-), and two acyclic monoterpenoids ( and ). Their structures were identified using one- and two-dimensional nuclear magnetic resonance spectroscopy, and mass spectrometry. To the best of our knowledge, compounds - were obtained from the genus for the first time. All isolates were tested for their ability to inhibit lipopolysaccharide-stimulated NO overproduction in RAW264.7 cells. Compound was found to inhibit NO production. Western blotting analysis indicated that active compound can regulate inducible NO synthase expression. In addition, lipopolysaccharide-induced interleukin 1 beta and interleukin-6 overproduction was reduced in a concentration-dependent manner.