The Study Of Combined Extraction And Purification Of Glabridin And Glycyrrhizic Acid

Glabridin and glycyrrhizic acid are two main active components in glycyrrhiza glabra.Glabridin is a hydrophobic flavonoid.It has whitening,antibacterial and antioxidant effects.It is widely used in medicine,food and cosmetics industries.Glycyrrhizic acid is a triterpene compound.It has anti-inflammatory,anti-cancer,antiviral,immune regulation and so on.It is widely used in medicine,cosmetics,tobacco and other industries.The separation and purification of glabridin and glycyrrhizic acid are the key problem in the development of natural active components of glycyrrhiza.In this paper,glabridin and glycyrrhizic acid were taken as the research objects.A simple and effective process for extraction and purification of glabridin and glycyrrhizic acid was established.Macroporous resin and molecularly imprinted materials were used to purify glabridin and glycyrrhizic acid extract.The specific process is as follows:The combined extraction process of glabridin and glycyrrhizic acid was studied.The ultrasonic method was selected as the extraction method,and the effects of solvent extraction,extraction temperature,liquid /solid ratio,extraction time and extraction times on the yield of glabridin and glycyrrhizic acid were studied.The results showed that when the extraction solvent was 60% ethanol,the extraction temperature was 45 ℃,the liquid /solid ratio was 20:1,the extraction time was 120 min and the extraction times were 1 times,the extraction technology was the best,the extraction rate of glabridin was 1.59‰ with the purity of 0.47%,the extraction rate of glycyrrhizic acid was 3.62% with the purity of 10.68%.Glabridin was separated from glycyrrhizic acid by extraction.Ethyl acetate was used as the extraction solvent.The purity of glabridin was determined to be 1.92%,the recovery rate was 100%,the purity of glycyrrhizic acid was 24.29%,and the recovery rate was 100%.HPD100 and HPD722 macroporous resin were used to purify glabridin and glycyrrhizic acid respectively.The purity of glabridin was increased to 19.7%,the recovery rate was 98.87%,the purity of glycyrrhizic acid was increased to 64.97%,and the recovery rate was 92.10% through the optimization of technological conditions.A series of molecularly imprinted polymers(MIPs)were prepared by precipitation polymerization with glycyrrhizic acid as the template.The preparation process of MIPs was investigated.When the monomer was methacrylic acid(MAA),the molar ratio of glycyrrhizic acid and monomer was 1:10,the cross-linker was the divinylbenzene(DVB),and the porogen was the mixed solution of 8 mL dimethylformamide(DMF)and 25 mL acetonitrile,MIPs showed the best adsorption performance for glycyrrhizic acid.The balanced adsorption capacity of glycyrrhizic acid was 398.5 mg/g and the imprinting factor was 3.73 in glycyrrhizic acid solution of 5 g/L.The effects of different polymerization conditions on the adsorption properties of MIPs were systematically studied by FTIR and BET and so on.The adsorption kinetics and adsorption isotherm of MIPs were also studied.The crude extract of glycyrrhizic acid was refined,and the purity of glycyrrhizic acid was increased to 73.10% with the recovery yield of 87.1%.A series of glabridin imprinted polymers were prepared by precipitation polymerization with glabridin as the template.The preparation process of MIPs was investigated.The results show that when the cross-linker was trimethylolpropane trimethacrylate(TRIM),the monomer was 1-vinylimidazole(1-VI)and the molar ratio of monomer and cross-linker was 1:2,the imprinted polymers showed the best adsorption performance for glabridin.The effects of different polymerization conditions on the adsorption properties of MIPs were systematically studied by SEM,BET and UV absorbance test.The adsorption kinetics and reusability of MIPs were also tested.Finally,the crude extract of glabridin was refined,and the purity of glabridin was increased to 36.3% with the recovery yield of 92.7%.