Separation of an Effective Component of Ligustilide from Volatile Oil of Angelica Sinensis by High Speed Countercurrent Chromatography and Its Analysis and Identification by GC-MS

High speed countercurrent chromatography (HSCC) was applied to the separation of an effective component of ligustilide from volatile oil of Angelica sinensis. The key to the success of this separation was the choice of the bi-phase solvent system. Based on the polarity of the target component and on the 3 essential requirements (i.e. 1 time of phase separation should be less than 30 s; 2 without leading to decomposition of the sample; 3 values of distribution coefficient K of the targent components should be in the range of 0.5-2.0) which should be followed in the choice of the bi-phase solvent system, the solvent system of n-hexane-ethylacetate-ethanol-water (1+1+1+1) was sieved among some other candidate solvent systems in the preliminary screening by TLC and HPLC. By using the selected bi-phase solvent system in the HSCC separation, when a portion of the oil sample (500 mg) was introduced, 48 mg of ligustilide was obtained after separation. As shown by the results found in the GC-MS study on the separated ligustilide, its purity attained to a high value of more than 98.5%, and through structural study, the compound was identified to be ligustilide.