酶法合成松香酸淀粉酯的抗氧化性研究

Study on Antioxidant Activity of Rosin Starch Ester by DPPH Method

采用酶催化方法合成了取代度为0.085的松香酸淀粉酯,经过红外光谱分析,发现在1 732 cm-1处产生酯键的特征吸收峰,扫描电镜分析结果表明酯化修饰化反应不仅发生在淀粉的非定型区,而且发生在淀粉的结晶区。在不同浓度、温度和p H的条件下,采用1,1-二苯基-2-三硝基苯肼(DPPH)法分析了松香酸淀粉酯的抗氧化性能。结果表明,与木薯淀粉、预处理淀粉相比,松香酸淀粉酯的抗氧化性得到提高。其中,在最佳浓度条件下,松香酸淀粉酯对DPPH自由基抑制率为31.66%,比木薯淀粉、预处理淀粉抑制率分别提高了1.14%和3.02%;在最佳p H条件下,松香酸淀粉酯对DPPH自由基抑制率为31.75%,比木薯淀粉、预处理淀粉抑制率分别提高了4.4%和2.1%;在最佳温度条件下,松香酸淀粉酯对DPPH自由基抑制率为32.95%,比木薯淀粉、预处理淀粉抑制率分别提高了2.37%和0.81%。该研究将为酶催化合成的松香酸淀粉酯在食品、化妆品等领域的应用提供理论依据。

Rosin acid starch with degree of substitution （DS） 0. 085 was prepared by enzymatic esterification reaction. The result of Fr-IR spectra analysis indicated that rosin acid starch exhibited a new absorption peaks at 1 732 cm^-1, which was attributed to the symmetric deformation vibration of carbonyl C = 0. The result of SEM analysis indicated that the esterification reaction not only occurred in the non-crystalline regions of starch, but also occurred inside the crystalline regions. The antioxidation property of rosin acid starch in different conditions temperature concentration and pH were analysis by DPPH method. The results indicated that compared with native starch and pretreated, the antioxidation property of rosin acid starch was improved. On the optimum concentration condition, the DPPH radical scavenging activity of rosin acid starch was 31.66% , that increased 1.14% and 3.02% than native starch and pretreated starch; On the optimum pH condition, the DPPH radical scavenging activity of rosin acid starch was 31.75% , that increased 4.4% and 2.1% than native starch and pretreated starch; On the optimum temperature condition, the DPPH radical scavenging activity of rosin acid starch was 32.95% , that increased 4.4% and 2.1% than native starch and pretreated starch 2.37% and 0.81%. This study will provide a theoretical basis for rosin acid starch application on food, cosmetics and other fields.