Isolation of new polyacetylenes from the roots of Eurycoma longifolia via high-speed counter-current chromatography

Eurycoma longifolia is a tropical plant of diverse applications in folk medicine, which occurs in Southeast Asia. In this study, pre-purified fraction (0.86   g) of the crude extracts from the roots of E. longifolia , was subjected to preparative high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of hexane–ethyl acetate–methanol–water (HEMWat) at a volume ratio of 5:2:5:2 ( v / v ). Longifolione A ( 1 , 19   mg, purity 96.0%) and longifolione C ( 3 , 317   mg, purity 96.2%), together with longifolione B ( 2 , purity 77.6%) were isolated in one run. The whole mobile and stationary phase was then blown out, concentrated in vacuo , and subjected to second HSCCC purification. Using HEMWat at a volume ratio of 6:1:6:1.2 ( v / v ), this fraction yielded two more new polyacetylenenes, longifolione D ( 4 , 5   mg purity 94.5%) and longifolione E ( 5 , 33   mg purity 96.3%). All of these five compounds are new natural products and isolated from E. longifolia for the first time. The established protocol for large-scale isolation of these polyacetylenes from E. longifolia was simple, efficient, and economical.