Studies on the constituents of the Japanese mistletoe, Viscum album L. var. coloratum Ohwi grown on different host trees.

The chemical constituents of the Japanese mistletoe, Viscum album L. var. coloratum OHWI, grown on 12 different kinds of host trees, were examined. Two new flavonoid glycosides, rhamnazin-3, 4'-di-O-glucoside and (2S)-homoeriodictyol-7-O-[apiosyl(1→2)]glucoside, were isolated from the n-BuOH extract. Two known flavonoid glycosides, flavoyadorinin-B and homo-flavoyadorinin-B, were also isolated. Moreover, comparative studies of the contents of three flavonoid glycosides in the Japanese mistletoe grown on the different host trees were carried out by high performance liquid chromatography. Flavonoid glycosides common to Japanese and European mistletoes were not found.