Extraction of Three Tanshinones from the Root of Salvia miltiorrhizaBunge by Supercritical Carbon Dioxide Fluid and Their Analysis with High Performance Liquid Chromatography
丹参中3种丹参酮的超临界二氧化碳萃取及液相分析

The extraction of three tanshinones from the root of Salvia miltiorrhiza Bunge by supercritical carbon dioxide (SC-CO2) fluid with ethanol as co-solvent was investigated using four-factor and three-level orthogonal design method and the systematic method. The optimized conditions were established as follows: 95% ethanol was selected as a co-solvent, flow rate of co-solvent was 1.0 mL/min, extraction pressure was 20 MPa, extraction temperature was 45 degrees C, separation temperature was 35 degrees C. The sample solution was separated on a Nova-Pak C18 column (3.9 mm i.d. x 300 mm, 5 microns) with CH3OH-H2O (80:20, V/V) as the mobile phase and detected at 280 nm. The correlation coefficients were 0.9994-0.9998 and the relative standard deviations were 2.37%-3.47%. The detection limits were 0.473 mg/L, 0.184 mg/L and 0.452 mg/L for tanshinone-II A, tanshinone-I and cryptotanshinone respectively.