Title
Effects of low frequency magnetic field on myoglobin oxidation stability
Author
Minquan Xia, Yinxia Chen, Jing Ma, Xiaoli Yin, Lan Wang, Wenjin Wu, Guangquan Xiong, Weiqing Sun, Yuanhua Zhou
Year
2020
Journal
Food Chemistry
Abstract
The effects of low frequency magnetic field on myoglobin (Mb) oxidation stability were evaluated by treatments at 0, 3, 6, 9, 12 mT and storage for 10 h. The results showed that Mb oxidation was inhibited under all magnetic field treatments, due to the increase of total sulfhydryl and free amino groups (9 or 12 mT) from unfolding of Mb clusters (3, 9, 12 mT) as well as β-turn and β-sheet structures (9 or 12 mT). The unfolding also induced (i) the destruction or burial of iron porphyrin and tyrosine residues; (ii) the exposure of tryptophan; (iii) more uniform Mb particle size distribution (3, 9, 12 mT) and increased zeta potential (3, 6, 12 mT). Overall, magnetic field promoted exposed active groups as the preferred oxidation target, thus decreasing the oxidation rate of central iron atoms. It also promoted Mb stability by redistributing particle size and increasing zeta potential.
Instrument
J-1500
Keywords
Circular dichroism, Secondary structure, Protein folding, Food science, Biochemistry