title: Synthesis, characterization and in vitro anti-diabetic activity of catechin grafted inulin.
abstract: In this study, a novel biological macromolecule with strong in vitro anti-diabetic activity was developed by grafting catechin onto inulin via a free radical mediated method. The characterization, α-glucosidase and α-amylase inhibitory activities of catechin grafted inulin (catechin-g-inulin) were investigated. Results showed that the grafting ratio of catechin-g-inulin was 124.8 mg CAE/g. UV-vis spectrum of catechin-g-inulin exhibited a new band at 280 nm, attributing to B ring of catechin moiety. FT-IR spectrum of catechin-g-inulin showed new absorption bands between 1540 and 1418 cm(-1), attributing to CC stretching vibration of catechin moiety. (1)H NMR spectrum of catechin-g-inulin preserved all the characteristic proton signals of inulin and partial signals of catechin. These all confirmed the successful grafting copolymerization. Conjugation probably occurred between OH of inulin (C-6) and H-6/H-8 of catechin (A ring). Catechin-g-inulin also exhibited increased thermal stability and crystallinity as compared to inulin. Moreover, in vitro anti-diabetic assays showed the α-glucosidase inhibitory activity decreased in the order of catechin-g-inulin>catechin>acarbose>inulin, and α-amylase inhibitory activity decreased in the order of catechin-g-inulin>acarbose>catechin>inulin. These indicated the potential of catechin-g-inulin in the development of a novel effective anti-diabetic agent.
authors: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China. Electronic address: junliu@yzu.edu.cn.
authors: Jun
authors: J
authors: Liu
authors: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors: Jian-feng
authors: JF
authors: Lu
authors: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors: Juan
authors: J
authors: Kan
authors: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors: Xiao-yuan
authors: XY
authors: Wen
authors: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors: Chang-hai
authors: CH
authors: Jin
mesh_terms: D002392:Catechin / Q000737:chemistry*; D004789:Enzyme Activation / Q000187:drug effects; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents / Q000737:chemistry* / Q000494:pharmacology*; D007444:Inulin / Q000737:chemistry* / Q000494:pharmacology* / Q000648:ultrastructure; D015394:Molecular Structure; D012995:Solubility; D013818:Thermogravimetry; D000516:alpha-Amylases / Q000037:antagonists & inhibitors
chemical_list: D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents; D002392:Catechin; D007444:Inulin; D000516:alpha-Amylases
keywords: Anti-diabetic; Catechin; Graft copolymer; Inulin; Redox pair