Chem. Pharm. Bull. 54(7) 1063—1066 (2006)

Viscum genus plants. But, they belong to different genera of Loranthaceae. The genus of Viscum, the plants of Loranthaceae family, are photosynthetic shrubby, hemiparasites on the tree branches. Viscum coloratum has commonly been used for Chinese medicine as a curative for a number of ailments such as hemorrhage, pleurisy, gout, heart disease, epilepsy, arthritis and hypertension. In our research, we found oleanolic acid showed significantly anti-inflammatory activitiy in V. articulatum. Oleanolic acid concentration-dependently inhibited superoxide anion generation by human neutrophils in response to fMLP (formyl-L-methionyl-Lleucyl-L-phenylalanine), but not to PMA (phorbol myristate acetate). It suggested that the inhibitory effect of oleanolic acid was through protein kinase C-independent pathway. In a previous screening for the inhibitory activities on superoxide anion generation in fMLP-stimulated human neutrophils by Viscum and Taxillus medicinal plants, V. coloratum also exhibited the strong inhibition. From V. coloratum, two new and thirty-nine known compounds were isolated and characterized. This paper deals with the structural determination of two new compounds, viscolin (4 ,4 -dihydroxy-2 ,3 ,6 ,3 -tetramethoxy-1,3-diphenylpropane) (1) and (2S )-7,4 -dihydroxy-5,3 -dimethoxyflavanone (2) by spectral analysis. The inhibitory activities of crude extract and pure compounds on neutrophils stimulated by fMLP/CB were also tested.