正交设计试验优化高速逆流色谱分离制备玛咖中芥子油苷的条件

基于高速逆流色谱（HSCCC）技术从玛咖中分离制备出两种芥子油苷，苄基芥子油苷（glucotropaeolin, GTL）和甲氧基苄基芥子油苷（glucolimnanthin, GLI）。使用正交设计试验对分离条件进行优化，采用高分辨质谱对制备的组分进行鉴定，采用高效液相色谱法（HPLC）对组分进行定量分析。确定了两个组分GTL与GLI的HSCCC最佳分离条件：溶剂系统为正丁醇-乙腈-200 g/L硫酸铵溶液（1:0.5:2.4, v/v/v），上相为固定相，下相为流动相，流动相流速2 mL/min，主机转速900 r/min，从玛咖根粗提物中一次性分离得到157.72 mg/kg纯度为97.9%的苄基芥子油苷和31.93 mg/kg的甲氧基苄基芥子油苷，固定相保留率达57.6%。该方法成本低，简便易行，样品损失量小，可大量循环进样制备。

Optimization of conditions for the isolation and preparation of glucosinolates from Maca by high-speed counter-current chromatography with orthogonal experiments

Glucosinolate is an important bioactive substance in Maca. In our study, two glucosinolates named glucotropaelin (GTL) and glucolimnanthin (GLI) were successfully separated from Maca with semi-preparative high-speed counter-current chromatography (HSCCC). For a best separation and better stationary phase retention, orthogonal experiments were carried out with the flow-rate of the mobile phase, ammonium sulfate concentration of biphasic solvent system, injection volume of crude extracts and the centrifugal speed of the apparatus as the four main factors. The separation was performed with the biphasic solvent system composed of normal butanol-acetonitrile-200 g/L ammonium sulfate solution (1:0.5:2.4, v/v/v) and the upper phase was used as the stationary phase and the lower phase as the mobile phase. The detection wavelength was set at 229 nm. The obtained optimum preparation conditions were that the mobile phase flow-rate was 2 mL/min, 500.00 mg crude extract was dissolved in 15 mL mobile phase, the ammonium sulfate concentration was 200 g/L and the centrifugal speed of the apparatus was 900 r/min. Under these conditions, a high efficiency separation of HSCCC was achieved, and 157.72 mg/kg of GTL and 31.93 mg/kg of GLI were obtained from the crude sample with a high stationary phase retention of 57.6%. The high performance liquid chromatography (HPLC) analysis showed that the purity of GTL was 97.9%. The identification and quantification of glucosinolates were completed by HPLC and mass spectrometry (MS). The established separation method is simple, less adsorption loss, lower cost and suitable for large scale separation of glucosinolates from Maca.