二聚甘油亚油酸酯的分离纯化及其性质分析

Separation, Purification, and Characterization of Diglycerol Linoleic Acid Esters

摘要:

采用Lipozyme 435脂肪酶催化合成的二聚甘油亚油酸酯，先用薄层层析(TLC)对产物定性分析，然后再用硅胶柱层析法对其进行分离纯化，最后通过高效液相色谱（HPLC-ELSD）和质谱（ESI-MS）对纯化组分进行定性分析。薄层层析（TLC）分离二聚甘油酯的理想条件为：点样量3 μL，以氯仿/丙酮/甲醇（96/4/2，V/V/V）展开15 min，于碘缸中碘蒸汽显色3 min；硅胶柱层析分离二聚甘油酯的理想条件为：2.0 g样品溶于5 mL氯仿-丙酮溶液（96/4，V/V），过硅胶层析柱（2.8 cm×60 cm，硅胶200~300目），以不同体积比的氯仿/丙酮/甲醇（96/4/0，95/3/2，96/4/5）为洗脱液依次进行梯度洗脱，流速为1.0 mL/min，按10 mL/管收集洗出液。同时对纯化后不同酯化度的二聚甘油酯进行DSC分析和HLB值测定，结果表明：随着酯化度的增加，二聚甘油酯的相变温度相应的增大，而HLB值反而相应的减小。

Abstract:

Diglycerol linoleic acid esters synthesized by Lipozyme 435 were qualitatively analyzed by thin layer chromatography (TLC), and then separated and purified by silica gel column chromatography. Finally, the purified products were analyzed by high-performance liquid chromatography with an evaporative light scattering detector (HPLC-ELSD) and electrospray ionization mass spectrometry (ESI-MS). The optimal TLC conditions for the separation of diglycerol linoleic acid ester were as follows: sample volume of 3 μL, separation time by chloroform-acetone-methanol solution (96/4/2, V/V/V) of 15 min, coloring time by iodine vapor of 3 min. The optimal silica gel column chromatography conditions for the separation of diglycerol linoleic acid ester were as follows: 2.0 g of sample was dissolved in 5 mL of chloroform-acetone solution (96/4, V/V), separated by a silica gel column (2.8 cm×60 cm, 200~300 mesh) using different mixtures of chloroform-acetone-methanol as the eluent (96/4/0, 95/3/2, 96/4/5, V/V/V) at a flow rate of 1.0 mL/min. Every 10 mL of eluted solution was collected in a tube. The obtained esters of diglycerol linoleic acid were analyzed by differential scanning calorimetry (DSC) and their hydrophilic-lipophilic balance (HLB) values were determined. The results showed that with increasing degrees of esterification, the phase transition temperatures of diglycerol linoleic acid esters increased, while their HLB values decreased.