Studies On Chemical Constituents Of Astragalus Membranaceus (Fisch.) Bge.

Astragalus membranaceus?Fisch.?Bge.is a member of the genus Astragalus.The roots of A.membranaceus is sweet in taste,tepid in nature and have been reported to possess the ability to tonify qi and lift yang,strengthen exterior and reduce sweat,induce diuresis for removing edema,fluid and blood,drain pus and expell toxin,and be used to treat deficiency of fatigue,poor appetite and loose stools,the syndrome of pectoral energy and internal heat diabetes.The chemical compositions of A.membranaceus are complex,mainly including flavonoids,triterpenoid saponins,polysaccharides.A lot of researches have shown that A.membranaceus has immunomodulatory,antioxidant,anti-aging,antifungal,antiviral,anticancer activities.25 compounds were isolated and purified from the EtOAc and n-BuOH of the aerial parts of A.membranaceus by solvent extraction,TLC analysis,normal and reverse phase silica gel,polyamide and Sephadex LH-20 column chromatography,along with recrystallization.The structures of all them were identified on the basis of spectral methods including ¹H NMR?¹³C NMR?MS and comparing with authentic samples,including 14 flavonoids,9 triterpenoid saponins,1 phenylpropionic acid,1steroid.Theyarecalycosin?AME-4?,formononetin?AME-5?,2'-methoxyisoliquiritigenin?AME-6?,2',4,4'-trihydroxychalcone?AME-7?,pendulione?AME-9?,liquiritigenin?AME-10?,pratensein?AME-16?,echinatin?AME-17?,3',4',7-trihydroxyflavone?AME-18?,3',7,8-trihydroxy-4'-methoxyisoflavone?AME-19?,4',7-dihydroxyflavone?AME-20?,licochalcone B?AME-21?,ononin?AME-22?,calycosin-7-O-?-D-glucopyranoside?AMB70-6?,astragalosideIV?AMB70-2?,cyclocanthoside E?AMB70-3?,isoastragaloside II?AMB70-4?,astragaloside II?AMB70-5?,astragaloside??AMB70-7?,isoastragaloside I?AMB70-9?,brachyosideB?AMB70-10?,cycloaralosideA?AMB70-11?,astragaloside I?AMB70-12?,4-hydroxycinnamic acid?AME-8?and?-sitostero?AME-1?.Among these compounds,AME-6,AME-8,AME-17,AME-18,AME-19,AME-20,AME-21 were isolated and identified in this genus for the first time.This work has made a contribution to provide a theoretical basis for the chemical studies on A.membranaceus.The content of calycosin-7-O-?-D-glucopyranoside and astragaloside IV is used for the quality control of A.membranaceus in Chinese Pharmacopoeia.This work summarize a simple method to separate these two compounds.