Effects of saikosaponin metabolites on the hemolysis of red blood cells and their adsorbability on the cell membrane

The hemolytic properties and the adsorbability on red blood cells of saikosaponin a, saikosaponin d and 13 metabolites formed in the alimentary tract were investigated. Among these compounds, saikosaponin d and its intestinal product, prosaikogenin G, which possess an alpha-hydroxyl function at C16, showed the strongest hemolytic activity at the dose range of 1.0 to 5.0 micrograms/ml. Saikosaponin a and its intestinal product, prosaikogenin F, which possess a beta-hydroxyl function at C16, showed activity above 10 micrograms/ml. In this case, the monoglycoside, prosaikogenin F, showed the stronger activity than the diglycoside, saikosaponin a. Among the gastric products whose ether ring was cleaved to produce a carbinol, the monoglycosides, prosaikogenin A and prosaikogenin H, showed a slight activity above 25 micrograms/ml, and the saikogenins except saikogenin A were inactive. Saikogenin A, however, had hemolytic activity at a dose of 15 micrograms/ml. The adsorbabilities of these compounds on red blood cell membranes closely paralleled their degrees of hemolytic activity.