Inhibition Effect of Achyranthes japonica N. Root Extract on Cathepsin B

This study was carried out to investigate the cathepsin B inhibition effect by Achyranthes japonica N. root extract in vitro. The methanol/(4:1, v/v) extract was fractionated by ethyl acetate(F1), chloroform(F2), chloroform/methanol(3:1, v/v)(F3) and methanol(F4). The yield of F4 in Achyranthes japonica N. root was . As an index material of Achyranthes japonica N. root, 20-hydroxy ecdysone was detected by TLC, and HPLC and it's content was . Three isolates(F1, F3, F4) showed the cathepsin B inhibition activity, and F4 showed the highest inhibition activity among them. In the inhibition activity on cathepsin B, leupeptin, 20-hydroxy ecdysone and F4(at the same concentration of 20-hydroxy ecdysone.) were 92, 88 and on BANA(-benzoyl-DL-arginine -naphthylamide) substrate, and 62, 36 and on CLN(-CBZ(carbobenzlyoxy)-L-lysine p-nitrophenyl ester HCI) substrate, respectively.