An Efficient Method to Separate the Main Constituents From Polygonatum cyrtonema Hua by a Combination of Online-Storage Inner-Recycling and Consecutive High-Speed Counter-Current Chromatography.

A novel strategy combining XAD-4 macroporous resin pretreatment and online-storage inner-recycling high-speed counter-current chromatography (OS-IRCCC) was developed for efficient separation of multi-polarity constituents from Polygonatum cyrtonema Hua. The innovation lies in the OS-IRCCC mode, which integrates online storage of target fractions via a six-way valve-equipped recycling loop and inner-recycling separation, overcoming limitations of conventional high-speed counter-current chromatography in resolving structurally similar compounds. After resin fractionation, 40%, 60%, and 95% ethanol eluates were separated using methyl tert-butyl ether/n-butanol/acetonitrile/water (1:4:1:5, v/v) solvent system, chloroform/methanol/water (7:6:4, v/v) solvent system (with OS-IRCCC for Compounds 8 and 9), and petroleum ether/ethyl acetate/methanol/water (5:5:4:3, v/v) solvent system, respectively. Thirteen compounds were successfully isolated, including four high-polarity glycosides (1-4), five medium-polarity phenolic constituents (5-9), and four low-polarity terpenes (10-13). This study demonstrates that the established separation method provides an efficient, rapid, and straightforward approach for isolating active constituents from P. cyrtonema Hua.