Separation and purification of compounds from piper kadsura using preparative reversed-phase liquid chromatography and preparative supercritical fluid chromatography

Abstract

A method based on preparative reversed-phase liquid chromatography (prep-RPLC) and preparative supercritical fluid chromatography (prep-SFC) was developed for the separation and purification of compounds from piper kadsura. A pretreatment method was first developed, including methanol extraction, water precipitation, petroleum ether extraction, etc. Chlorophyll and other strong polar impurities were removed from the piper kadsura samples, and the target components were enriched in petroleum ether extracts. The piper kadsura samples were separated into 18 fractions on a Unitary C18 column (250 mm×20 mm, 5 μm) with water and methanol as the mobile phases. Then, the SFC parameters, including the column, modifier, temperature, and backpressure were optimized. The optimized conditions for prep-SFC were as follows:XAmide column (250 mm×20 mm, 5 μm), methanol as the modifier, 30℃ column temperature, and 15.0 MPa backpressure. Because of the good orthogonality of RPLC and SFC, six highly pure compounds were isolated, including kadsurenone, wallichinine, denudatin B, pellitorine, 2E-decenoic acid N-isobutylamide, and futoxide.