摘要
【目的】探究磁场作用下水合环境影响肌红蛋白(myoglobin,Mb)氧化稳定性的作用机制,为改善Mb的氧化稳定性提供依据。【方法】在4℃下,设置低强度(3 mT)和高强度(12 mT)两种磁场环境,磁场分别处理Mb水溶液、Mb粉末、去离子水(磁场处理去离子水后再溶解Mb),磁场处理时间为1h,以未经磁场处理的Mb水溶液作为对照。通过高铁肌红蛋白的相对含量、血红素铁含量以及紫外吸收带的变化情况来分析Mb的氧化稳定特性;同时,利用圆二色谱、拉曼光谱和荧光光谱技术分析Mb二级结构、三级结构及卟啉铁结构的变化,探究磁场对Mb氧化稳定性的作用机理。【结果】磁场直接处理Mb粉以及磁场处理溶剂水,然后再溶解Mb,两种处理方式均对高铁肌红蛋白相对含量无显著影响(P>0.05),而3 mT和12 mT磁场处理Mb水溶液均显著提高了高铁肌红蛋白的相对含量。血红素铁含量和血红素邵氏带紫外吸收结果显示,血红素卟啉环结构对磁场环境很敏感,不同强度的磁场对Mb血红素结构均有显著的破坏,并且高强度的磁场环境对卟啉环结构破坏程度相对更大。Mb三级结构和二级结构结果表明,3 mT磁场先处理溶剂水再溶解Mb,以及3 mT和12 mT磁场处理Mb水溶液均显著促进Mb二级结构的展开和侧链基团色氨酸和酪氨酸残基的氧化损伤。拉曼光谱结果显示,12 mT磁场处理Mb水溶液促使Mb通过二硫键进行交联。【结论】Mb水溶液中水合作用直接影响磁场对肌红蛋白氧化特性的作用效应,磁场处理促进Mb中心铁以及血红素卟啉环的氧化,可能是磁场改变了水分子的介电性、电离程度等物理性质,以及Mb与水之间的氢键状态,进一步影响了Mb的结构,α-螺旋结构展开,侧链基团暴露,加速了血红素结构的破坏和血红素铁的流失,促进了中心铁的氧化。
【Objective】To investigate the mechanism of action of hydration environment affecting the oxidative stability of myoglobin(Mb)in the presence of a magnetic field,and to provide a basis for improving the oxidative stability of Mb.【Method】Two magnetic field environments of low intensity(3 mT)and high intensity(12 mT)were set up at 4℃,the magnetic field treated Mb aqueous solution,Mb powder,and deionized water(the magnetic field treated deionized water and then dissolved Mb),respectively,and the magnetic field treatment time was 1 h.The Mb aqueous solution without magnetic field treatment was used as the control.The oxidative stability properties of Mb were analyzed by the relative content of high iron myoglobin,heme iron content and the variation of UV absorption bands,while the changes of Mb secondary structure,tertiary structure and porphyrin iron structure were analyzed by circular dichroism,and Raman spectroscopy and fluorescence spectroscopy techniques were employed to investigate the mechanism of the effect of magnetic field on the oxidative stability of Mb.【Result】Both magnetic field treatment of Mb powder directly and magnetic field treatment of solvent water followed by dissolution of Mb had no significant effect(P>0.05)on the relative content of methemoglobin,while both 3 mT and 12 mT magnetic field treatment of Mb aqueous solution significantly increased the relative content of methemoglobin.The results of heme iron content and heme Shore band UV absorption showed that the heme porphyrin ring structure was sensitive to the magnetic field environment,and the magnetic field of different intensities had significant damage to the Mb heme structure,while the high intensity magnetic field environment had relatively greater damage to the porphyrin ring structure.Mb tertiary and secondary structure results showed that both 3 mT magnetic field treatment of solvent water before dissolving Mb,and 3 mT and 12 mT magnetic field treatment of Mb aqueous solution significantly promoted the unfolding of Mb s
作者
邓雨诗
夏民权
马静
周元华
孙卫青
DENG YuShi;XIA MinQuan;MA Jing;ZHOU YuanHua;SUN WeiQing(College of Life Science,Yangzte University,Jingzhou 434020,Hubei;College of Mechanical Engineering,Yangzte University,Jingzhou 434020,Hubei)
出处
《中国农业科学》
CAS
CSCD
北大核心
2023年第22期4523-4531,共9页
Scientia Agricultura Sinica
基金
国家自然科学基金(31771993)。
关键词
肌红蛋白
磁场
水合环境
氧化
卟啉
myoglobin
magnetic field
hydrated environment
oxidation
porphyrin
