title: Structure, physical property and antioxidant activity of catechin grafted Tremella fuciformis polysaccharide.
abstract: In this study, structural characterization, physical property and antioxidant activity of catechin grafted Tremella fuciformis polysaccharide (catechin-g-TPS) were investigated. Crude polysaccharides were isolated from the fruit bodies of T. fuciformis and further purified on DEAE-52 and Sepharose CL-4B chromatography to afford a main purified fraction (named TPS). The molecular weight of TPS was determined as 5.82 × 10(5)Da by HPLC. Then, the free radical mediated grafting of catechin onto TPS was achieved by using a redox system. As compared with the unmodified TPS, catechin-g-TPS showed new bands within the range of 1300-1600 cm(-1) in FT-IR spectrum, and exhibited new signals at around δ 6.00 and 6.80 ppm in (1)H NMR spectrum. Thermogravimetric analysis indicated the thermal stability of catechin-g-TPS was higher than TPS. X-ray diffraction spectrum of catechin-g-TPS exhibited two sharp narrow diffraction peaks at 14.2 and 32.1°, corresponding to the crystalline peaks of catechin. Scanning electron microscopy observation revealed the surface of TPS was smooth, whereas the surface of catechin-g-TPS was much rough. These results all confirmed the successful grafting of catechin onto TPS. Moreover, catechin-g-TPS had higher 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and reducing power as compared to TPS.
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China. Electronic address: junliu@yzu.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors.forename: Chen-Guang
authors.initials: CG
authors.lastname: Meng
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors.forename: Ye-Hua
authors.initials: YH
authors.lastname: Yan
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors.forename: Ya-Na
authors.initials: YN
authors.lastname: Shan
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Kan
authors.affiliation: College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
authors.forename: Chang-Hai
authors.initials: CH
authors.lastname: Jin
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D001487:Basidiomycota / Q000737:chemistry*; D002392:Catechin / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry / Q000494:pharmacology; D062610:Fungal Polysaccharides / Q000737:chemistry*; D008970:Molecular Weight; D010084:Oxidation-Reduction / Q000187:drug effects; D066244:Proton Magnetic Resonance Spectroscopy; D017550:Spectroscopy, Fourier Transform Infrared; D013329:Structure-Activity Relationship; D013818:Thermogravimetry; D014961:X-Ray Diffraction
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D062610:Fungal Polysaccharides; D002392:Catechin
keywords: Antioxidant; Catechin; Grafted; Tremella fuciformis polysaccharide