Influence of oxidation on myofibrillar proteins degradation from bovine via μ-calpain

► We examine if oxidation could influence on the degradation of myofibrillar protein via μ-calpain in vitro. ► Oxidation increased the proteolytic susceptibility of myosin heavy chain. ► Relatively higher oxidative level accelerated the degradation of α-actinin. ► Oxidation caused little proteolysis of actin. ► Oxidation declined the degradation of troponin-T, but had no influence on the pattern of 30 kDa fragment.