RESUMO
Objective: To establish a simple and effective method for the isolation of leonurine from Leonurus japonicus by high speed countercurrent chromatography (HSCCC). Methods: The extraction conditions of leonurine were optimized by one-factor experimental design. After comparing several different solvent systems, the two phase system of ethyl acetate-n-butanol-water (3∶2∶5) was finally chosen as operating solvent of HSCCC for the separation of leonurine, in which the lower phase was determined as the mobile phase and the upper phase as stationary. The detection of eluates was performed with an ultraviolet detector at 277 nm. The rotation speed was adjusted at 850 r/min, and the flow rate was 2.2 mL/min. Results: Leonurine was successively isolated from n-butanol fraction by HSCCC, and the above established method was also successively applied to the crude extact of L. japonicus. Finally, 68 mg of leonurine with purity about 96.2% could be obtained from 2.48 g crude extract of L. japonicus in a single injection. Conclusion: The described approaches actively promote efficient preparation strategy to obtain high purity of leonurine.