title: Extraction Optimization, Preliminary Characterization and Bioactivities in Vitro of Ligularia hodgsonii Polysaccharides.
abstract: The optimization extraction, preliminary characterization and bioactivities of Ligularia hodgsonii polysaccharides were investigated. Based on single-factor experiments and orthogonal array test, the optimum extraction conditions were obtained as follows: extraction time 3 h, temperature 85 °C, water/raw material ratio 36. Further Sevag deproteinization and dialysis yielded the dialyzed Ligularia hodgsonii polysaccharides (DLHP, 19.2 ± 1.4 mg/g crude herb). Compositional analysis, size-exclusion chromatography connected with multi-angle laser light-scattering and refractive index (SEC-MALLS-RI), Fourier transform infrared (FT-IR) and ¹H nuclear magnetic resonance (NMR) spectroscopy were employed for characterization of the polysaccharides. DLHP was found to have a major component with a weight-average molecular weight of 1.17 × 10⁵ Da, mainly comprising of glucose, galactose, arabinose, mannose, rhamnose, glucuronic acid and galacturonic acid. By in vitro antioxidant activity assays, DLHP presented remarkable scavenging capacities towards 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and hydroxyl radicals, and ferrous ions chelating ability. Moreover, it exhibited appreciable anti-hyperglycemic activity as demonstrated by differential inhibition of α-glucosidase and α-amylase. The results indicated that DLHP could potentially be a resource for antioxidant and hypoglycemic agents.
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China. XuepingSong@whu.edu.cn.
authors.forename: Xueping
authors.initials: X
authors.lastname: Song
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China. tangj0205@whu.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Tang
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D019659:Asteraceae / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D065089:Glycoside Hydrolase Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D007004:Hypoglycemic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D008970:Molecular Weight; D010936:Plant Extracts / Q000302:isolation & purification; D010946:Plants, Medicinal / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000516:alpha-Amylases / Q000037:antagonists & inhibitors
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents; D010936:Plant Extracts; D011134:Polysaccharides; D000516:alpha-Amylases
keywords: Ligularia hodgsonii Hook.; anti-hyperglycemic activity; antioxidant activity; characterization; extraction optimization; polysaccharides