Extraction and Isolation of Saponins

Due to their special structural features, extraction and isolation of saponins poses a serious challenge. Conventional methods have been explored as well as the recent, relatively greener, efficient, solvent-economic, time-saving, newer methods of extraction. Both traditional and recent methods of isolation are also discussed. Finally, examples are given involving both conventional and newer methods of extraction and isolation. Though in general it is difficult to use a single technique for isolation of saponins, recent literature work seems to point to the fact that high speed counter-current separation coupled to evaporative light scattering detector (ELSD) gives superior separation. The ELSD appears to have circumvented the long-standing problem of saponin detection as most of these do not have a chromophore, and hence making UV detection only nonspecific and at range 200–210 nm.