Qinghai Key Laboratory of Qinghai-Tibet Plateau Biological Resources, Chinese Academy of Science, Northwest Institute of Plateau Biology, Xining, P. R. China.
Savaid Medical School, University of the Chinese Academy of Sciences, Beijing, P. R. China.
J Sep Sci. 2019 Feb;42(3):684-690. doi: 10.1002/jssc.201800812. Epub 2018 Dec 11.
The separation of minor compounds, especially those with similar polarities from a complex sample, remains challenging. In the proposed study, an effective method based on medium-pressure liquid chromatography and recycling high-speed counter-current chromatography was developed for the enrichment and separation of three minor components from Dracocephalum tanguticum. The crude extract was directly introduced to medium-pressure liquid chromatography for the enrichment of the three minor components. Based on high-performance liquid chromatography analysis, the total content of these three compounds increased from 0.48% in the crude extract to 85.3% in the medium-pressure liquid chromatography fraction. In addition, high-speed counter-current chromatography was employed to separate the enriched compounds using the solvent system hexane/ethyl acetate/methanol/water (1.18:8.82:1.18:8.82, v/v/v/v). As a result, compound 3 and a mixture of compounds 1 and 2 were obtained. In order to improve the resolution of compounds 1 and 2 while saving separation time, a recycling and heart-cut mode was used. Finally, compounds 1 and 2 were obtained after five cycles. These compounds were identified as 3-phenylethyl β-d-glucopyranoside (1), tazettoside E (2), and cirsiliol-4'-glucoside (3). Compounds 1 and 2 were primarily separated from D. tanguticum. Moreover, the developed method provided a reference for the separation of minor components from the complex sample.
从复杂样品中分离微量化合物，特别是那些具有相似极性的化合物，仍然具有挑战性。在本研究中，提出了一种基于中压液相色谱和再循环高速逆流色谱的有效方法，用于从唐古特青兰中富集和分离三种微量成分。将粗提取物直接引入中压液相色谱，以富集三种微量成分。基于高效液相色谱分析，这三种化合物的总含量从粗提取物中的 0.48%增加到中压液相色谱馏分中的 85.3%。此外，还采用高速逆流色谱法，以正己烷/乙酸乙酯/甲醇/水（1.18:8.82:1.18:8.82，v/v/v/v）为溶剂体系分离富集的化合物。结果得到化合物 3 和化合物 1 和 2 的混合物。为了在节省分离时间的同时提高化合物 1 和 2 的分辨率，采用了再循环和心切模式。最后，经过五次循环，得到了化合物 1 和 2。这些化合物被鉴定为 3-苯乙基 β-d-吡喃葡萄糖苷（1）、塔西妥苷 E（2）和梓醇-4'-葡萄糖苷（3）。化合物 1 和 2 主要从唐古特青兰中分离出来。此外，所开发的方法为从复杂样品中分离微量成分提供了参考。
