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作 者 ：孙志敏， 陈群超， 黄建颖， 李昂

期 刊 ：核农学报 2016年 30卷 2期 页码：295-303

关键词：壳聚糖；抗氧化活性；自由基清除能力；

Keywords:chitosan, antioxidant activity, radical scavenging capacity,

摘 要 ：为研究吡啶壳聚糖的抗氧化活性,将吡啶小分子基团经化学接枝合成吡啶壳聚糖,利用傅里叶红外光谱、紫外-可见光谱、核磁共振光谱对其进行结构表征,并测定其取代度、水溶性、毒性及体外抗氧化活性。结果表明,吡啶成功接枝至壳聚糖,得到水溶性较好、取代度为0.66的吡啶壳聚糖,属实际无毒;以水溶性壳聚糖为对照,吡啶壳聚糖对·OH、DPPH自由基的清除能力以及还原能力均有提高;在β-胡萝卜素漂白体系中,吡啶壳聚糖的IC₅₀为0.9 mg·mL^-1,当其浓度为1.8 mg·mL^-1时,对亚油酸氧化的抑制率为60.7%,优于对照组(27.5%)。本研究为壳聚糖在食品添加剂、自由基清除剂等中的应用提供了理论依据与参考。

Abstract:The aim of this study is to synthesize pyridine chitosan(Py-chitosan) by introducing the pyridine group onto the chitosan backbone and test its antioxidant activity. The resulting polymer was characterized by FT-IR, UV-vis and NMR. The degree of substitution (DS), solubility, toxicity and in-vitro antioxidant activity of Py-chitosan were further investigated. Results showed that pyridine was introduced onto chitosan with substitution degree of 0.66 and better water-soluble properties and it was non-toxic. Scavenging power for ·OH, DPPH and reducing power of Py-chitosan had been improved compared with water soluble chitosan (WSC). In the β-carotene bleaching assay, Py-chitosan showed strong inhibition power towards linoleic acid. Also, IC₅₀ of Py-chitosan was 0.9 mg·mL^-1 and at 1.8 mg·mL^-1, the inhibition rate was up to 60.7%, while that of WSC was 27.5%. The study will provide theoretical basis and reference for application of chitosan in the field of food additives and free-radical scavengers.

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