Rapid Purification of Huperzine A and B with Two Polystyrene based Resins by Preparative Low‐Pressure Liquid Chromatography

Abstract

A rapid, facile, and environmentally friendly process was developed for purification of huperzine A (HupA) and huperzine B (HupB) from the Chinese traditional herb Huperzia serrata. The process consisted of two steps of preparative low‐pressure liquid chromatography (LPLC) on two polystyrene based resins, successively. The first step removed a large amount of impurities and captured HupA and HupB using Amberlite XAD‐4 from the herbal extraction prepared by 1% aqueous H₂SO₄. This step was more efficient than multi‐cycle liquid‐liquid extraction as an initial separation step. The second step was able to separate HupA and HupB, employing a novel uniform polystyrene based porous microsphere named PST as the packing material. The PST column demonstrated a better separation and shorter run time compared with a commercial C₁₈ column. The mobile phases used in both LPLC's simply consisted of water and ethanol that are considered to be of low toxicity. Combination of the XAD‐4 and PST chromatography and one step of crystallization enabled purification of HupA and HupB from 0.18% and 0.08% to 98.2% and 98.8%, respectively, with total recoveries of 82.8% and 84.3%.

Keywords:

• Huperzia serrata
• Huperzine A
• Huperzine B
• Preparative low‐pressure liquid chromatography
• Purification

Acknowledgment

This work was supported by the National Natural Sciences Foundation of China (Grants Contract No. 20136020 and 20125616).