Use resin like Diaion HP-20, XADs followed by Sephedex LH-20, C-18.

If you havnt C-18 then you have go for Silica (60-120) 0r silica (200-300)

gudluck

:)

if your saponins is not pure, then you can go again for acidification of product in methano up to pH 6-7, filter it again and immediate wash with ether, acetone nad methanol, by this you can save yield loss by purification.