Title
Effect of Mild Ozone Oxidation on Structural Changes of Silver Carp (Hypophthalmichthys molitrix) Myosin
Author
Wenxin Jiang, Yufan He, Shanbai Xiong, Youming Liu, Tao Yin, Yang Hu, Juan You
Year
2017
Journal
Food and Bioprocess Technology
Abstract
To produce high-quality surimi, we investigated the effect of ozone-induced mild oxidation on structural changes of silver carp myosin by analyzing circular dichroism (CD), intrinsic fluorescence, the sulfhydryl group, surface hydrophobicity, SDS-PAGE, and dynamic light scattering (DLS) of myosin. Mild ozone oxidation of myosin was performed by applying gaseous ozone for a short time. Results showed that the content of sulfhydryl group decreased, and carbonyl content and surface hydrophobicity increased with an increase in ozone treatment time. A red shift in the maximum wavelength of intrinsic fluorescence indicated the unfolding of oxidized myosin. Further conformational change of myosin was illustrated by CD; α-helical content decreased significantly and β-turn, β-sheet, and random coil content increased with increased ozone treatment time, which demonstrated the rearrangement of β-structure in myosin. The results from DLS and SDS-PAGE indicated that soluble oligomers or aggregates were formed by disulfide bonds under mild ozone treatment. Therefore, ozone-induced mild oxidation did not strongly alter myosin structure but promoted myosin partial unfolding, which might result in exposing more cross-linking sites for the formation of surimi gel.
Instrument
J-1500
Keywords
Circular dichroism, Secondary structure, Chemical stability, Food science, Biochemistry