黔产皂角米多糖提取动力学及抗氧化活性研究

目的：以皂角米为原料，研究皂角米多糖的提取动力学及其抗氧化活性。方法：以Fick第一定律为基础，建立皂角米多糖的提取动力学模型，采用红外光谱对皂角米多糖进行结构分析，通过测定皂角米多糖对ABTS自由基、羟基自由基、1，1-二苯基-2-三硝基苯肼（DPPH）自由基、超氧阴离子自由基的清除能力来评价其抗氧化活性。结果：建立的皂角米多糖提取动力学模型计算值与实际测得数据吻合良好，符合一级提取动力学模型，其活化能为15.023 kJ/mol；红外图谱显示皂角米多糖含有甘露糖，为β-型吡喃多糖。抗氧化结果表明，皂角米多糖的抗氧化活性随着浓度的增大而增强。当浓度为5 mg/mL时，皂角米多糖对ABTS阳离子自由基清除率为71.82%，对羟基自由基清除率为83.36%，对DPPH清除率为84.00%，对超氧阴离子自由基清除率为86.11%。结论：建立了皂角米多糖提取的动力学模型，皂角米多糖具有较好的抗氧化活性。

Extraction Kinetics and Antioxidant Activities of Polysaccharides from Seeds of Gleditsia sinensis in Guizhou

Objective: To study the extraction kinetics and antioxidant activity of polysaccharides from seeds of Gleditsia sinensis. Methods: Based on Fick’s first law,the extraction kinetic model was established,and the structure of polysaccharides from seeds of Gleditsia sinensis was analyzed by infrared spectrum.The scavenging ability of polysaccharides from seeds of Gleditsia sinensis on ABTS free radical,hydroxyl autoradical,1,1-diphenyl-2-trinitrophenyl hydrazine(DPPH)free radical and superoxide anion radical was determined to evaluate its antioxidant activity. Results: The results showed that the calculated value of the kinetic model was in good agreement with the actual measured data,which was in accordance with the first-order extraction kinetic model,and the activation energy was 15.023 kJ/mol.The infrared spectrum showed that polysaccharides from seeds of Gleditsia sinensis contained mannose,which was β-type pyran polysaccharide. The antioxidant activity of polysaccharide increased with the increase of concentration. When the concentration was 5 mg/mL,the scavenging rates of ABTS,DPPH and superoxide anion were 71.82%,83.36%,84.00% and 86.11%,respectively. Conclusion: The kinetic model of the polysaccharide extraction was established,and polysaccharides from seeds of Gleditsia sinensis had good antioxidant activity.