title: Preparation and in vitro antioxidant activities of 6-amino-6-deoxychitosan and its sulfonated derivatives.
abstract: The 6-amino-6-deoxychitosan (NC) and their 2, 6-di-N-sulfonated derivatives were prepared via N-phthaloylation, tosylation, azidation, hydrazinolysis, reduction of azide groups and N-sulfonation, and their structures were systematically characterized by FT-IR, 2D HSQC NMR, XRD, gel permeation chromatography (GPC), and elemental analysis. The 6-amino-6-deoxychitosan showed effect in three selected antioxidant essays, including reducing power, superoxide anion radical scavenging ability, and hydroxyl radical scavenging effect. But the factors affecting each activity were different. The reducing power and the superoxide anion radical scavenging ability of NC were strong and closely related to the amino groups in the molecular chains. Both introducing N-sulfonated groups into NC and the concentration reduction of NC and its sulfonated derivatives decreased these activities. For the superoxide anion radical, the molecular charge property was also a significant influence factor. For the hydroxyl radical, NC only showed weak scavenging activity in a special inverse concentration-dependent manner. However, the incorporation of N-sulfonated groups significantly improved the scavenging activity, and the more N-sulfonated groups, the higher the concentrations, the stronger the activity was. The results could be due to the different conformations of NC and its sulfonated derivatives in aqueous solution.
authors: Department of Environmental Engineering, School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China.
authors: Jianhong
authors: J
authors: Yang
authors: Department of Environmental Engineering, School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China.
authors: Qinyue
authors: Q
authors: Xie
authors: Department of Environmental Engineering, School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China.
authors: Jianfeng
authors: J
authors: Zhu
authors: Department of Environmental Science, College of Resource and Environmental Science, Wuhan University, Wuhan, 430079, Hubei, China.
authors: Chang
authors: C
authors: Zou
authors: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada T6G 2P5.
authors: Lingyun
authors: L
authors: Chen
authors: Department of Environmental Science, College of Resource and Environmental Science, Wuhan University, Wuhan, 430079, Hubei, China.
authors: Yumin
authors: Y
authors: Du
authors: Department of Environmental Engineering, School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China.
authors: Dinglong
authors: D
authors: Li
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D048271:Chitosan / Q000031:analogs & derivatives* / Q000737:chemistry; D002850:Chromatography, Gel; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D017550:Spectroscopy, Fourier Transform Infrared; D013481:Superoxides / Q000737:chemistry
chemical_list: C517097:6-amino-6-deoxy-chitosan; D000975:Antioxidants; D013481:Superoxides; D048271:Chitosan
keywords: 6-amino-6-deoxychitosan; antioxidant; influence factor; sulfonation