麦麸阿拉伯木聚糖-牛血清白蛋白酶促共聚物制备及其乳化性能研究

Peroxidase-mediated Conjugation of Wheat Bran Arabinoxylan and Bovine Serum Albumin to Improve Emulsifying Properties

研究麦麸阿拉伯木聚糖与牛血清白蛋白在过氧化物酶的催化下形成多糖-蛋白质共聚物。通过紫外可见光分光光度计测定不同过氧化物酶添加量、不同H2O2浓度、不同麦麸阿拉伯木聚糖与牛血清白蛋白质量比3个因素下,麦麸阿拉伯木聚糖与牛血清白蛋白酶促共聚物紫外吸收光度值变化,并利用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)及高效尺寸排阻色谱(high performance size exclusion chromatography,HPSEC)技术对酶促共聚物进行定性表征,研究在3个因素下,麦麸阿拉伯木聚糖与牛血清白蛋白酶促共聚物乳化活性及乳化稳定性变化规律。结果表明麦麸阿拉伯木聚糖可以通过过氧化物酶与牛血清白蛋白发生接枝反应,且酶添加量为0.2 U/g,H2O2浓度为0.5 mol/L,麦麸阿拉伯木聚糖与牛血清白蛋白质量比为10∶1时,紫外吸收光度值变化最明显,且酶促共聚物具有较好的乳化活性及乳化稳定性,分别为212.426 m^2/g及32.419 min。

Wheat bran arabinoxylan was conjugated with bovine serum albumin by horseradish peroxidase to obtain polysaccharide-protein conjugates. The UV absorbance of wheat bran arabinoxylan-bovine serum albumin conjugates were determined by UV-visible spectrophotometry with three factors:peroxidase addition,hydrogen peroxide concentration,the mass ratio of wheat bran arabinoxylan to bovine serum albumin. The formation of hetero-crosslinked wheat bran arabinoxylan-bovine serum albumin conjugates was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)and high performance size exclusion chromatography(HPSEC)analyses. Meanwhile,the emulsifying properties of wheat bran arabinoxylan-bovine serum albumin conjugates was studied. Results showed that wheat bran arabinoxylan could be grafted with bovine serum albumin by horseradish peroxidase. And the UV absorbance was the most obvious when the amount of enzyme added was 0.2 U/g,the concentration of hydrogen peroxide was 0.5 mol/L,and the mass ratio of wheat bran arabinoxylan to bovine serum albumin was 10 : 1,the change of UV absorption photometric value was most obvious. The enzymatic conjugates had good emulsifying activity and emulsifying stability,respectively 212.426 m^2/g and 32.419 min.