In Vitro Anticomplementary Activity of Hederagenin Saponins Isolated from Roots of Dipsacus asper

Anticomplementary activity of hederagenin and related saponins isolated from Dipsacus asper was investigated in vitro. HN saponin F (3) was most potent with $IC_{50}$ value of$ 3.7{\times}10^{-5} M$ followed by 3-O-${\beta}-D-glucopyranosyl-(1{\rightarrow} 3)-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}2)-{\beta}-L-arabinopyranosyl$ hederagenin $28-O-{\beta}-D-glucopyranosyl-(1{\rightarrow}6)-beta$-D-glucopyrano side (8), $3-O-{\beta}-L-arabinopyranosyl$ hederagenin $28-O-{\beta}-D-glucopyranosyl-(1{\rightarrow}6)-{\beta}-D-glucopyranoside$ (5), dipsacus saponin A (4), and hederagenin (1) on the classical pathway (CP) of complement system, while the saponins 3-5 did not show the inhibition of hemolysis and rather increase the hemolysis on the alternative pathway (AP). However, all of C-3 monodesmosides [prosapogenin CP (2), dipsacus saponin B (6), and dipsacus saponin C (7)] evoked hemolysis directly on the erythrocytes.