Proteomic profiling and oxidation site analysis of gaseous ozone oxidized myosin from silver carp (Hypophthalmichthys molitrix) with different oxidation degrees

Abstract

Ozone is used to in surimi production and affects the conformation of myosin and gelling properties. Amino acid analysis, SDS-PAGE, in-gel trypsin hydrolysis and LC-MS/MS were used to investigate the effect of the ozone treatment time on the oxidation principle of amino acids to identify the oxidation site and oxidation mechanism of myosin with different oxidation degrees. The results showed that the order of ozonation of amino acids from easy to difficult was tyrosine > cysteine > histidine > proline. The protein structure near the SH1-SH2 region initially changed when the ozone treatment time was 50 s. Prolonging the oxidation to 80 s leads to an irregular distribution of oxidation sites. Ten min of ozone treatment resulted in the aggregation from the SH1 helical region and myosin rod. This study helped to clarify the mechanism of ozone oxidation, thus providing a theoretical basis for producing surimi products of improved quality.