Study On The Process Of High-Effective Extraction And Separation Of Isoliquiritigenin

Acid hydrolysis, enyme catalysis and ultrasonic extraction of isoliquiritigenin (ISLG) from licoricewas studied. The separation and purification of ISLG were done with column chromatography on macroporous resin and polyamides, the ISLG content was analysed by HPLC.1. A rapid RP-HPLC method was set up to analyse ISLG contents in the tested samples. Separations conditions: C₁₈ (250mm×4.6mm i.d., 5μm particle size) stainless steel column(HPLC Technology Ltd., Japan), the mobile phase methanol / 0.4% phosphoric acid (v/v) 1:1, flow rate 1 mL/min , injection volume 10 μL, column compartment temperature 30°C, and the wavelengths 360 run.2. The direct acid hydrolysis and enzyme-assisted extraction of ISLG from licorice were compared and optimized. Different parameters of optimal process were as follows:1) For acid hydrolysis extraction conditions of ISLG: 1mol·mL^-1 HCl, ratio of liquid to material 5: 1, acid hydrolysis at 90℃ for 2h. After adjusted to pH =7, the residues were extracted by 80% alcohol, the ratio of liquid to material 10: 1, ultrasonic extraction 20min and two times;The filtrate was extracted by EtOAc, the ratio of volume 1:1, repeated one time.2) For cellulase-assisted extraction conditions of ISLG: pH=7, 0.4mg/mL ecllulase, 45℃ for 48h, ratio of enzymatic solution to material 8:l(mL/g licorice), agitation speed 100rpm.The yield of ISLG of cellulase-assisted extraction was 2.98‰, which was 1.21 folds, 11.07 folds and 10.38 folds as high as that of acid hydrolysis, direct Soxhlet extraction and direct ultrasonic extraction, respectivly. And the ISLG content of ointment of cellulase-assisted extraction was 3.32%, which was 1.10 folds, 10.64 folds and 11.92 folds as that of acid hydrolysis, direct Soxhlet extraction and direct ultrasonic extraction, respectivly.3. Ultrasonic extraction method was used to extract ISLG from the residue after enzyme-asssisted treatment. The orthogonal test indicated the optimum ultrasonic extraction conditions of ISLG were as follows: 80% alconol as solvent, ratio of liquid to material 10:1, ultrasonic extraction time 10min, three times.The extraction yield of ISLG was 3.11‰ and the ISLG content of ointment was 3.55%.4. The separation of ISLG was done with column chromatography on ADS-F8 macroporous resin. The optimum adsorption and desorption parameters of separation of ISLG with ADS-F8 macroporous resin were as follows, adsorption: pH=7, temperature 20℃, flow rate 1.5 mL/min;desorption: 15% alcohol 100mL (eluted), elution solvent 80% alcohol, flow rate 1.5 mL/min. After treated with ADS-F8 macroporous resin, the recovery yeild of ISLGwas 60.6% and the purity was increased from3.55% to 27.77% with 7.82 folds as high as that of cellulase-asssisted ethanol ultrasonic extract.5. Then polymide column chromatography was further used to purify ISLG from macroporous resin. Elution solvent was 40% alcohol. The purity of ISLG was increased from 27.77% to 78.67% and increased 50.9%, and the recovery yield of ISLG was 64.37%.