title: Identification, quantification and antioxidant activity of acylated flavonol glycosides from sea buckthorn (Hippophae rhamnoides ssp. sinensis).
abstract: A novel acylated flavonol glycoside: isorhamnetin (3-O-[(6-O-E-sinapoyl)-β-D-glucopyranosyl-(1→2)]-β-D-glucopyranosyl-7-O-α-L-rhamnopyranoside) (1), together with two known acylated flavonol glycosides: quercetin (3-O-[(6-O-E-sinapoyl)-β-D-glucopyranosyl-(1→2)]-β-D-glucopyranosyl-7-O-α-L-rhamnopyranoside) (2) and kaempferol (3-O-[(6-O-E-sinapoyl)-β-D-glucopyranosyl-(1→2)]-β-D-glucopyranosyl-7-O-α-L-rhamnopyranoside) (3) were isolated from the n-butanol fraction of sea buckthorn (Hippophae rhamnoides ssp. sinensis) berries for the first time by chromatographic methods, and their structures were elucidated using UV, MS, (1)H and (13)C NMR, and 2D NMR. Compounds 1-3 showed good scavenging activities, with respective IC50 values of 8.91, 4.26 and 30.90 μM toward the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical; respective Trolox equivalent antioxidant capacities of 2.89, 4.04 and 2.44 μM μM(-1) toward 2,2'-azino-bis-3-ethyl-benzothiazoline-6-sulphonate (ABTS) radical. The quantitative analysis of the isolated acylated flavonol glycosides was performed by HPLC-DAD method. The contents of compounds 1-3 were in the range of 12.2-31.4, 4.0-25.3, 7.5-59.7 mg/100 g dried berries and 9.1-34.5, 75.1-182.1, 29.2-113.4 mg/100 g dried leaves, respectively.
authors.affiliation: Department of Pharmacognosy, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
authors.forename: Chu
authors.initials: C
authors.lastname: Chen
authors.forename: Xue-Min
authors.initials: XM
authors.lastname: Xu
authors.forename: Yang
authors.initials: Y
authors.lastname: Chen
authors.forename: Meng-Yao
authors.initials: MY
authors.lastname: Yu
authors.forename: Fei-Yan
authors.initials: FY
authors.lastname: Wen
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D044948:Flavonols / Q000737:chemistry*; D006027:Glycosides / Q000737:chemistry*; D031281:Hippophae / Q000737:chemistry*; D013058:Mass Spectrometry; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D044948:Flavonols; D006027:Glycosides; D010936:Plant Extracts
keywords: Acylated flavonol glycosides; Antioxidant activity; HPLC; Hippophae; NMR; Sea buckthorn