Isolation and structure determination of a new flavone glycoside from seed residues of seabuckthorn (<i>Hippophae rhamnoides</i> L.)

<p>In this study, a valid method was established for the isolation and purification of flavone glycosides from <i>Hippophae rhamnoides</i> L. seed residues using high-speed counter-current chromatography in one step, with a solvent system of ethyl acetate-methanol-n-butyl alcohol-water (9:1:0.5:9, <i>v/v</i>/<i>v/v</i>). A total of 28.8 mg compound <b>I</b> and 57.3 mg compound <b>II</b> were obtained from 200 mg of flavone H-glycosides rich extract, with purities of 98.3 and 96.4%, respectively. The structures of two compounds were identified by MS and NMR. 3-O-β-D-Sophorosylkaempferol-7-O-{3-O-[2(E)-2,6-dimethyl-6-hydroxyocta-2,7-dienoyl]}-α-L-rhamnoside is compound<b> I</b> and compound <b>II</b> named hippophanone is a new compound were identified by MS and NMR. The method was efficient and convenient, which could be used for the preparative separation of flavone glycosides from <i>H. rhamnoides</i> L. seed residues.