INTRODUCTION: Cynanchum bungei Decne (Baishouwu in China), is a famous traditional Chinese medicine that has been widely used as a tonic medicine or health food for centuries. Bungeiside-A, bungeiside-B and baishouwubenzophenone, as the major bioactive constituents in C. bungei, are challenging to separate and purify since bungeiside-A and -B are present in very low concentrations and have similar structures and high polarity. OBJECTIVE: To develop a method of isolation and purification of bungeiside-A and -B and baishouwubenzophenone from the Chinese medicinal plant Cynanchum bungei Decne by high-speed counter-current chromatography (HSCCC). METHODOLOGY: The roots of C. bungei were extracted with light-petroleum (60-90 °C) and chloroform to remove the lipid substance. Then the residuals were extracted with methanol. The methanol extract was prepared for the subsequent HSCCC separation. The simple HSCCC method of separation and purification of bungeiside-A and -B and baishouwubenzophenone was established according to the solvent system, which was selected according to the measurement of partition coefficient (K). The purities of target compounds were test by HPLC and the structure was identified by ¹H NMR and ¹³C NMR. RESULTS: Bungeiside-A (9.4 mg), bungeiside-B (8.6 mg) and baishouwubenzophenone (5.7 mg) were obtained from 1.5 g of the methanol extract with purities of 93.2, 98.7 and 95.4%, respectively. CONCLUSION: These results clearly demonstrate that HSCCC is a powerful tool for isolating and purifying components with similar structures, low concentration and high polarity from medicinal plant, such as bungeiside-A and -B and baishouwubenzophenone.
INTRODUCTION:Cynanchum bungei Decne (Baishouwu in China), is a famous traditional Chinese medicine that has been widely used as a tonic medicine or health food for centuries. Bungeiside-A, bungeiside-B and baishouwubenzophenone, as the major bioactive constituents in C. bungei, are challenging to separate and purify since bungeiside-A and -B are present in very low concentrations and have similar structures and high polarity. OBJECTIVE: To develop a method of isolation and purification of bungeiside-A and -B and baishouwubenzophenone from the Chinese medicinal plant Cynanchum bungei Decne by high-speed counter-current chromatography (HSCCC). METHODOLOGY: The roots of C. bungei were extracted with light-petroleum (60-90 °C) and chloroform to remove the lipid substance. Then the residuals were extracted with methanol. The methanol extract was prepared for the subsequent HSCCC separation. The simple HSCCC method of separation and purification of bungeiside-A and -B and baishouwubenzophenone was established according to the solvent system, which was selected according to the measurement of partition coefficient (K). The purities of target compounds were test by HPLC and the structure was identified by ¹H NMR and ¹³C NMR. RESULTS:Bungeiside-A (9.4 mg), bungeiside-B (8.6 mg) and baishouwubenzophenone (5.7 mg) were obtained from 1.5 g of the methanol extract with purities of 93.2, 98.7 and 95.4%, respectively. CONCLUSION: These results clearly demonstrate that HSCCC is a powerful tool for isolating and purifying components with similar structures, low concentration and high polarity from medicinal plant, such as bungeiside-A and -B and baishouwubenzophenone.