Effect of pulsed electric field on assembly structure of α-amylase and pectin electrostatic complexes
Effect of pulsed electric field on assembly structure of α-amylase and pectin electrostatic complexes
复制标题
脉冲电场对α-淀粉酶和果胶静电复合物组装结构的影响
DOI：
10.1016/j.foodhyd.2019.105547
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发表时间：
2020-04-01
影响因子：
10.7
通讯作者：
Huang, Qingrong
中科院分区：
文献类型：
--
作者：
Jin, Weiping;Wang, Zhifeng;Huang, Qingrong
脉冲电场可以改变蛋白质和多糖分子的电荷分布，影响它们之间的相互作用和复合物的聚集，但这些影响还没有得到充分的评价。本文研究了高压静电场对α-淀粉酶和果胶静电结合复合物的影响。采用荧光、FTIR、DSC、酶活、粒径、zeta电位、CLSM和SEM等方法对α-淀粉酶分子构象和α-淀粉酶/果胶复合物组装结构的变化进行了研究。经脉冲电场（E = 20 kV/cm，t（exp）= 1 ms，5次循环）处理后，α-淀粉酶的内源荧光被猝灭，β折叠含量增加，酶活损失近80%，变性温度升高。α-淀粉酶/果胶复合物的Zeta电位没有明显变化，但粒径逐渐增大。利用Turbiscan记录了α-淀粉酶/果胶复合物的粒径变化，其粒径增长模型符合异速生长函数。最后，α-淀粉酶和果胶的复合物在PEF处理后趋向于分枝状、环状或圆形形状。
Pulsed electric field (PEF) could change the charge distribution of proteins and polysaccharides and affect their interactions and complexes aggregation, but those influences are not enough evaluated. Here, the effects of PEF on the complexes of alpha-amylase and pectin driven by electrostatic binding were studied. Changes in molecular conformation of alpha-amylase and assembly structure of alpha-amylase/pectin complexes were orderly assessed by fluorescence, FTIR, DSC, enzyme activities, particle size, zeta-potential, CLSM, and SEM. After PEF treatment (E similar to 20 kV/cm, t(exp)similar to 1 ms, and 5 cycles), the intrinsic fluorescence of alpha-amylase was quenched, the content of beta-sheet increased, enzyme activities lose almost 80%, and the denatured temperature increased. Zeta-potential of alpha-amylase/pectin complexes did not change significantly, but the particle size rose gradually. The particle revolution of alpha-amylase/pectin complexes was recorded by Turbiscan, and the size growth model fit the Allometric function well. Finally, the complexes of alpha-amylase and pectin after PEF treatment tended to the branched, ring, or circles-like shape.