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Synthesis, antioxidant and cathepsin D inhibition activity of quaternary ammonium chitosan derivatives
Wenjuan Li1, Yunfei Duan1, Jianying Huang1
1Key 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.
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.
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