L-精氨酸改性淀粉的制备及其抗菌薄膜的性能研究

Study on the Preparation of L- arginine Modified Starch and the Properties of Its Antibacterial Films

摘要:

以玉米淀粉（St）、丙烯酸甲酯（MA）与L-精氨酸（L-Arg）为原料，采用酯化—氨解两步法将碱性氨基酸—L-精氨酸引入淀粉大分子上，制备了具有抑菌性能的精氨酸改性淀粉（StMA-Arg）。阐述了反应机理，用拉曼光谱（RAM）与X-射线衍射谱（XRD）表征了产物的结构，通过单因素实验优化了反应条件。随后以L-精氨酸改性淀粉为原料制备了抗菌膜，并考察了薄膜的亲疏水性能、力学性能、抑菌性能及在土壤中的稳定性。结果表明，StMA-Arg薄膜的力学性能较天然淀粉膜显著改善，同时疏水性增强。StMA-Arg薄膜对大肠杆菌显示出明显的抑菌活性，且抑菌圈较小，属于接触式抑菌。土壤失重实验结果显示，StMA-Arg薄膜40D后的失重率为27.90%，远小于天然淀粉膜（40D失重率为72.15%）。作为一种潜在的环境修复材料的基体，StMA-Arg及其薄膜抑菌性与耐分解性能的增强，对提高淀粉类天然高分子材料的稳定性，延长其使用寿命，扩大其使用范围，以最终实现其在环境修复领域的工业化应用具有重要意义。

Abstract:

With Corn starch (St), methyl acrylate (MA) and L- arginine (L-Arg) as raw materials, basic amino acids were introduced into the starch molecules by the two step of esterification and ammonolysis process ,the antibacterial modified starch (StMA-Arg) was prepared. The reaction mechanism was introduced, the structures of the products were characterized by Raman spectroscopy (RAM) and X- ray diffraction (XRD) analysis, the reaction conditions were optimized by single factor experiments. The antibacterial films were prepared by using the modified starch as raw material. The hydrophobic properties, mechanical properties, antibacterial activity and stability of the films were investigated. The results showed that the mechanical properties of StMA-Arg film were significantly improved compared with native starch film, and the hydrophobicity of the film was enhanced. StMA-Arg film showed obvious antibacterial activity to Escherichia coli, and the bacteriostatic circle was small, which belongs to contact bacteriostasis. The results of weight loss experiment showed that the weight loss rate of StMA-Arg film was 27.90% after 40D, which was much lower than that of native starch film (40D weight loss rate was 72.15%) . As a potential substrate for environmental remediation, the enhance in antibacterial activity and the degradation resistance of StMA-Arg and its films were of great significance to improving the stability of starch-type natural polymer materials, prolonging its service life and expanding its application scope, so as to realizing its industrial application in the field of environmental remediation.