Structure characterization and antioxidant activity of a novel polysaccharide isolated from Ginkgo biloba.
A novel polysaccharide (GBP50S2) with antioxidant activity was isolated from Ginkgo biloba. The structure of GBP50S2 was elucidated on the basis of physico-chemical and instrumental analyses, and its average molecular weight (Mw=2.30x10(5)) was determined by gel permeation chromatography. The backbone of GBP50S2 was composed of (1-->4)-linked alpha-d-mannopyranosyl residues which branched at O-3. The three branches consisted of beta-l-rhamnopyranosyl residues, (1-->4)-linked alpha-d-galactopyranosyl terminated with beta-l-rhamnopyranosyl residues, and (1-->3,4)-linked alpha-d-mannopyranosyl terminated with beta-l-rhamnopyranosyl residues, respectively. In the in vitro antioxidant assay, GBP50S2 was found to possess DPPH radical-scavenging activity and hydroxyl radical-scavenging activity with an IC(50) value of 0.412 mg/mL and 0.482 mg/mL, respectively.
Department of Natural Products Chemistry, Jinan University, Guangzhou, PR China.
Fei
F
Yuan
Rongmin
R
Yu
Yin
Y
Yin
Jianru
J
Shen
Quanfeng
Q
Dong
Ling
L
Zhong
Liyan
L
Song
D001713:Biphenyl Compounds / Q000378:metabolism; D002240:Carbohydrate Sequence; D002845:Chromatography; D016166:Free Radical Scavengers / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D020441:Ginkgo biloba / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010851:Picrates / Q000378:metabolism; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*
D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D010851:Picrates; D011134:Polysaccharides; D017665:Hydroxyl Radical; C004931:1,1-diphenyl-2-picrylhydrazyl