Separation of alkaloids from herbs using high-speed counter-current chromatography

Alkaloids represent a most widespread group of bioactive natural products. Because of their alkalinity and structural diversity, the fractionation and purification of the alkaloids from herbs can often present a number of practical difficulties using the conventional chromatographic techniques. High‐speed counter‐current chromatography (HSCCC) is a liquid–liquid partition chromatography with a support‐free liquid stationary phase, and is gaining more and more popularity as a viable separation technique for bioactive compounds from natural resources. In the present review, focus is placed on the separation of alkaloids by both conventional HSCCC and pH‐zone‐refining counter‐current chromatography (CCC) techniques from herbs. The review presents the separation of over 120 different alkaloid compounds from more than 30 plant species by the conventional HSCCC and pH‐zone‐refining CCC. Based on the data from the literature, the proper solvent systems for the separation of alkaloids by the conventional HSCCC and pH‐zone‐refining CCC are also summarized.