title: Synthesis, antioxidant and cathepsin D inhibition activity of quaternary ammonium chitosan derivatives.
abstract: Two (2-hydroxypropyl) trimethyl ammonium and/or imidazole-based quaternary ammonium chitosan derivatives (NHT-chitosan and Im-OHT-chitosan) were synthesized by using nucleophilic substitution reaction. These two synthesized chitosan derivatives were characterized by Fourier transform infrared spectroscopy, NMR spectra, and UV-visible spectra. The applications as antioxidant agents and cathepsin D inhibitors were further investigated. Both of quaternary ammonium chitosan derivatives exhibited good antioxidant activity upon scavenging against hydroxyl radical and hydrogen peroxide as well as the lipid peroxidation inhibition in the linoleic acid emulsion system. They also exhibited good inhibition activity of cathepsin D protease. NHT-chitosan and Im-OHT-chitosan are potential the natural, healthy and safe preservatives in food industry.
authors.affiliation: Key Laboratory of Fruits and Vegetables Postharvest and Processing Technology Research of Zhejiang Province, College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, PR China.
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Li
authors.affiliation: Key Laboratory of Fruits and Vegetables Postharvest and Processing Technology Research of Zhejiang Province, College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, PR China.
authors.forename: Yunfei
authors.initials: Y
authors.lastname: Duan
authors.affiliation: Key Laboratory of Fruits and Vegetables Postharvest and Processing Technology Research of Zhejiang Province, College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, PR China. Electronic address: huangjy@zjgsu.edu.cn.
authors.forename: Jianying
authors.initials: J
authors.lastname: Huang
authors.affiliation: Key Laboratory of Fruits and Vegetables Postharvest and Processing Technology Research of Zhejiang Province, College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, PR China. Electronic address: zhengqunxiong@zjgsu.edu.cn.
authors.forename: Qunxiong
authors.initials: Q
authors.lastname: Zheng
mesh_terms: D002402:Cathepsin D / Q000737:chemistry*; D048271:Chitosan / Q000031:analogs & derivatives* / Q000737:chemistry; D016166:Free Radical Scavengers / Q000138:chemical synthesis* / Q000737:chemistry; D011480:Protease Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*
chemical_list: D016166:Free Radical Scavengers; D011480:Protease Inhibitors; D000644:Quaternary Ammonium Compounds; D048271:Chitosan; D002402:Cathepsin D
keywords: Antioxidant activity; Cathepsin D inhibitor; Chitosan; Imidazole; Quaternary ammonium