Inhibitory effect of bupleuri radix saponins on adhesion of some solid tumor cells and relation to hemolytic action: screening of 232 herbal drugs for anti-cell adhesion.

Anti-cell adhesive activity and hemolytic action of herbal drugs were investigated. Among 232 herbal drugs tested, six showed a remarkable anti-cell adhesive activity, and the extract from the roots of Bupleurum falcatum (Umbelliferae), the semen of Psorala corylifolia (Leguminosae), and the semen of Areca catechu (Palmae) showed an anti-cell adhesive action at non-cytotoxic concentrations. Saikosaponins-a, d and e, isolated from the roots of Bupleurum falcatum, exhibited a potent anti-cell adhesive activity and a strong hemolytic action. In a structure-activity relationship for both activities, it seems that a sugar moiety and an ether linkage between C-13 and C-28 are required for good bioactivities. In addition, saikosaponin d with a beta-hydroxy group at C-16 was more potent than saikosaponin a possessing an alpha-hydroxy group. Taken together, it is suggested that the mechanism for anti-cell adhesive activity of saikosaponin may resemble that for their hemolytic action.