Qinghai Key Laboratory of Qinghai-Tibet Plateau Biological Resources, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, P.R. China.
Savaid Medical School, University of Chinese Academy of Sciences, Beijing, P.R. China.
J Sep Sci. 2017 Jun;40(11):2515-2521. doi: 10.1002/jssc.201601134. Epub 2017 Mar 15.
In our present study, two groups of xanthones isomers (1-hydroxy-3,5,8-trimethoxyxanthone and 1-hydroxy-3,7,8-trimethoxyxanthone; 1,8-dihydroxy-3,7-dimethoxyxanthone and 1,8-dihydroxy-3,5-dimethanolxanthone) and other two xanthones (3-methoxy-1,5,8-trihydroxyxanthone and 3,5-dimethoxy-1-hydroxyxanthone) were separated from Swertia franchetiana. First, a solvent system composed of petroleum ether/methanol/water (2:1:0.6, v/v) was developed for the liquid-liquid extraction of these xanthones from the crude extract. Then, an efficient method was established for the one-step separation of these six xanthones by high-speed countercurrent chromatography using n-hexane/ethyl acetate/methanol/ethanol/water (HEMEW; 6:4:4:2:4, v/v) as the solvent system. The results showed that liquid-liquid extraction could be well developed for efficient enrichment of target compounds. Additionally, high-speed countercurrent chromatography could be a powerful technology for separation xanthones isomers. It was found ethanol could be a good methanol substitute when the HEMEW system could not provide good separation factors.
在本研究中，从川西獐牙菜中分离得到了两组二氢黄酮醇类化合物（1-羟基-3,5,8-三甲氧基呫吨酮和 1-羟基-3,7,8-三甲氧基呫吨酮；1,8-二羟基-3,7-二甲氧基呫吨酮和 1,8-二羟基-3,5-二甲氧基呫吨酮）和另外两种呫吨酮（3-甲氧基-1,5,8-三羟基呫吨酮和 3,5-二甲氧基-1-羟基呫吨酮）。首先，开发了一种由石油醚/甲醇/水（2:1:0.6，v/v）组成的溶剂系统，用于从粗提取物中液液萃取这些呫吨酮。然后，使用正己烷/乙酸乙酯/甲醇/乙醇/水（HEMEW；6:4:4:2:4，v/v）作为溶剂系统，建立了一种高效的一步分离这六种呫吨酮的高速逆流色谱法。结果表明，液液萃取可以很好地开发，用于有效富集目标化合物。此外，高速逆流色谱法可以成为分离黄酮醇类化合物异构体的有力技术。当 HEMEW 系统不能提供良好的分离因子时，发现乙醇可以很好地替代甲醇。
