Isolation and characterization of Swainsonine from Texas locoweed (Astragalus emoryanus)

Abstract

Swainsonine (1,2,8-trihydroxyoctahydroindolizine) was isolated from locoweed (Astragalus emoryanus) that grows in Texas. Using a biological assay as a measure of activity and purity, a relatively strightforward purification of the compound is described. The purified material was a potent inhibitor of jack bean α-mannosidase and also of glycoprotein processing. The positive ion electron impact mass spectra of this compound was identical to that of authentic swainsonine. Nuclear magnetic resonance analysis also confirmed that the material was swainsonine.