Study On The Extraction, Separation And Purification Methods Of Medical Components For Liquorice

With the aim of extraction, separation and purification of medicine components from Liquorice, we performed extraction experiments of liquorice using various methods, including supercritical CO2 extraction, room-temperature immersion and ultrasonic extraction. The optimum extraction conditions were found, and the extracted products were analyzed by MS. The following results are obtained based on the experiments:Flavonoids were extracted from liquorice using supercritical CO2 extraction. A variety of factors were investigated, including liquorice granularity, extraction pressure, temperature, extraction time and flow rate of CO2. In addition, cosolvent type and its concentration and dosage were also examined. Based on the separate effect of these factors on the product yield, the optimal extraction conditions were determined. The product yield was 7.03% at 16MPa and 50°C.To obtain polar products from liquorice, we performed room-temperature immersion and ultrasonic extraction, and compared the three different extraction methods based on extraction efficiency and product distribution. The product yield was 7.72% and 8.92% with the ultrasonic extraction and the room-temperature immersion method, respectively. Besides, the product distribution was very different with the three different extraction methods. Following supercritical CO2 extraction, the material was subjected to ultrasonic extraction and an extraction yield of 4.85% was obtained. The total extraction yield from a combination of the two-extraction process was 11.88%, with flavonoids as the major product in supercritical CO2 extraction and Glycyrrhizic Acid in ultrasonic extraction.The crude extracts were separated by TLC and Column Layer Chromatography. It was found that SCCO2 extracts were composed of 7 group components, while ultrasonic extracts included 7 group components and room-temperature immersion extracts had 2 group components. The component identification of these groups were determined by MS. SCCO2 extracts had a lot of flavonoids, glycycoumarin and Glycyrrhetinic Acid. But Glycyrrhizic Acid, with high molecular weight and strong polarity, was very difficult to be extracted by SCCO2.