Study On The Chemical Composition And Biological Activity Of The Upper Part Of Ural Licorice

Glycyrrhiza uralensis(licorice)is a medicinal plant worldwide.Its roots and rhizomes are popularly used as the herbal medicine Gan-Cao,to treat respiratory infections,gastric ulcer,diabetes,whitening and other modern clinical applications.The proportion of biomass in the aerial part of licorice is large,and the annual output of licorice is as high as 50,000 tons,the aerial part has not been well developed and utilized.The aerial part of the licorice is currently used in animal husbandry and has certain effects in improving animal health.This study aims to elucidate the bioactive componentes.Firstly,the chemical components of aerial part were isolated.Secondly,bioactivities of the compounds were evaluated by using rapid screening models.Finally,the bioactivities of aerial part and underground part were further confirmed by in vivo.1.Isolation of chemical constituents of aerial part of Glycyrrhiza uralensis Fisch.In order to clarified the effective ingredients of aerial part of Glycyrrhiza uralensis Fisch.,we isolated its chemical components systematically.The crude drug materials(10kg)of aerial part of Glycyrrhiza uralensis were extracted by 90%and 70%EtOH,and the combined extract was partitioned successively with petroleum ether,ethyl acetate,n-butanol and water.The ethyl acetate extract was repeatedly separated by various column chromatography over silica gel,polyamide,Sephadex LH-20,and were then purified by semi-preparative RP-HPLC.Finally,a total of 97 compounds(1-97)were obtained from the aerial part.12 compounds of them are new,including prenylated isoflavanones(1-5),isoflavanes(6-9),a 2-aryl coumarone(10),a pterocarpan(87)and a coumarin(88).The structures of new compounds were identified by extensive NMR and HR-MS data analyses,and the absolute configurations were established by ECD spectral calculations.2.Biological activities screening of compoundsSystematic biological activities screening of the 97 compounds has been established.According to literature and laboratory experimental reports,86 compounds(1-86)were screened by using two enzyme based models,including PTP1B inhibition,and a-glucosidase inhibition,The bioactive compounds were summarized and evaluated their ICs50 values.These compounds may be important effective components of the aerial part.3.In vivo bioactivities studies of aerial part and underground partThe in vivo bioactivities of aerial part and underground part were studied.Diabetic animal model db/db mice were selected to further evaluate their efficacy.In this work,the aerial part(ethanol extract,300mg/kg)showed significant anti-diabetic effects on diabetic db/db mice.It could decrease the blood glucose level and increase the serum insulin level compared to the control group.The results indicated that the aerial part has anti-diabtic effects.In conclusion,the chemical constituents and pharmacological activities of the aerial part of licorice were systematically studied.The results clarified the effective components will help to improve resource utilization of aerial part.And the results of efficacy in vivo provide a theoretical basis for the development and utilization of aerial part of licorice.