Study On The Extraction And Purification Processes Of Isoliquiritigenin And Glycyrrhizic Acid From Licorice

Extracting and purifying isoliquiritigenin and glycyrrhiza acid from the licorice were studied by supercritical carbon dioxide extraction, large diameter resin and silica chromatography, and vacuum-cavitated extraction.1. The better HPLC analysis conditions were as follows, chromatographic column ODS, detecting wavelength 254 nm, ,flowing rate 1mL/min,injected sample volume 10uL, mobile phase CH₃OH-H₂O-HOAc.2. Obtained the better process conditions of supercritical CO₂ extraction isoliquiritigenin:particle size : 60 sieve meshbatch amount: 5Kg/kettleextraction pressure : 30 Mpaextraction temperature : 45℃entrainer: 85% ethanolratio of solvent to solid: 5:1CO₂ flow rate: 10Kg/hextraction time: 4hseparation pressure: 5.5Mpaseparation temperature : 35℃The yield of isoliquiritigenin was 0.035% and the content was 0.84%, which were 3.5 times and 3.0 times as those as results by soxhlet extraction method.3. Studied the purification of isoliquiritigenin through large diameter resin and silica chromatography, and AB-8 large diameter resin and silica chromatography were choosed. The final yield of islioquiritigenin was 0.01% and the content was 90%.4.Extracting GA by the vacuum-cavitated method was studied through effect factors and orthotropic experiments. The optimum process was as follows : solvent is 0.3% ammonia solution , ratio of solvent to solid ratio is 10:1(mL/g) , vacuum-cavitated time is 15 minutes , GA extraction yeild is 2.0% , the crude extract is 30.3% , and in which the content of GA is 6.6% .The yield of monoammonium glycyrrhizinate was 1.30% and content was 95% by the lixiviation, ammoniation, acidation, decoloration and recrystal.This process used the licorice resource sufficiently, and obtained isoliquiritigenin and glycyrrhiza acid in one process from raw material , and provided the strong base of theory and practice to develop licorice medicine with high quality and profits.