制备型高速逆流色谱分离纯化长松萝中的松萝酸

利用制备型高速逆流色谱分离纯化长松萝中的松萝酸，经过高效液相色谱、核磁共振检测，确定其纯度及结构。将长松萝破碎后用石油醚(60～90℃)回流浸提4h，浸提液经过滤浓缩后得到松萝酸粗提物。采用正己烷:乙腈:乙酸乙酯:水(8:7:5:0.8，V/V)的两相体系将所得的粗提物进行制备型高速逆流色谱的分离纯化，一次进样25mg，可得到11.2mg 样品。利用高效液相色谱检测该样品纯度达到99%。将得到的样品进行1H-NMR、13C-NMR检测确定其化学结构，并确定该样品为松酸。实验证明制备型高速逆流色谱可以成功地将长松萝中的松萝酸进行分离纯化。

Isolation and Purification of Usnic Acid from Usnea longissima by Preparative High-speed Counter-current Chromatography

Preparative high-speed counter-current chromatography (HSCCC) was used for the isolation and purification of usnic acid from Usnea longissima. Crude extract was firstly obtained by reflux extraction with petroleum ether at 60 to 90 ℃ for 4 h from dried Usnea longissima. Then hexane-acetonitrile-ethyl acetate-water (8:7:5:0.8, V/V) was used as the two-phase solvent system for purification. Finally the collected components were analyzed using high-performance liquid chromatography (HPLC) and the structure of main component was identified using 1H-NMR and 13C-NMR. By this way, the 11.2 mg of usnic acid is obtained from 25 mg of the crude extract of dried Usnea longissima with the purity of 99%.