The effect of gamma and electron beam irradiation on the structural and physicochemical properties of myofibrillar protein and myosin from grass carp

Myofibrillar protein (MPS) and myosin (MS) from grass carp was irradiated by gamma-ray and electron beam (EB) irradiation with different dose (2, 4, 6, 8, and 10 kGy). The changes in the physicochemical properties (solubility, Ca2+-ATPase activity, total and reactive sulfhydryl content, surface hydrophobicity [S-0-ANS]), and structure of MPS and MS were investigated in the present work. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed that there were degradation and aggregation of MPS and MS caused by irradiation, and the disappearance of myosin heavy chains (MHC) irradiated by EB was earlier than that of irradiated by gamma-ray. As compared with MPS, the extracted MS was more easily destroyed. With the increase of irradiation dose, the particle size, solubility, Ca2+-ATPase activity, and SH content of MPS and MS decreased (p < .05), while the S-0-ANS first increased and then decreased. Two-way analysis of variance results suggested that the degree of protein denaturation depends on the irradiation mode and dose. Compared with gamma-ray irradiation, the EB irradiation had a greater impact on the physicochemical properties of MPS and MS.

Automated summary

The research findings showed that exposure to different doses of radiation resulted in changes in the physicochemical properties of myofibrillar protein and myosin from grass carp, with electron beam irradiation having a greater impact compared to gamma-ray irradiation.