Characterization of mitogenic pectic polysaccharides from kampo (Japanese herbal) medicine "juzen-taiho-to"

The acidic polysaccharide fraction (F-5-2) from "Juzen-Taiho-To" (TJ-48), a Kampo (Japanese herbal) medicine prepared by decocting a prescription of 10 kinds of herbs, has potent mitogenic activity. In order to clarify the mitogenic activity, F-5-2 was fractionated by amon-exchange chromatography, and 14 acidic polysaccharide fractions were obtained. Mitogenic activities of these polysaccharides were increasing with their molecular masses and affinities to the anion-exchange column. Methylation analysis and endo-alpha-(1----4)-polygalacturonase digestion showed these polysaccharide fractions to be pectic polysaccharides, many of which consisted mainly of polygalacturonan regions in addition to small amounts of "ramified" regions. Gel filtration showed that the molecular masses of the "ramified" regions of the polysaccharides were similar. High molecular mass polygalacturonic acid showed a weak mitogenic activity. The mitogenic (M-1 and M-2) and non-mitogenic (M-3) polysaccharides from the most active polysaccharide fraction (F-5-2IIh) were further purified by gel filtration. M-2 and M-3 were also shown to be pectic polysaccharides, and the neutral glycosidic linkages in M-2 and M-3 were different from each other. Endopolygalacturonase digestion markedly decreased the mitogenic activity of M-2, however, the "ramified" region of M-2 still showed a weak activity.