Improved physicochemical properties and hepatic protection of Maillard reaction products derived from fish protein hydrolysates and ribose.

High amounts of waste products generated from fish-processing need to be disposed of despite their potential nutritional value. A variety of methods, such as enzymatic hydrolysis, have been developed for these byproducts. In the current study, we investigated the physicochemical, biological and antioxidative properties of fish protein hydrolysates (FPH) conjugated with ribose through the Maillard reaction. These glycated conjugates of FPH (GFPH) had more viscous rheological properties than FPH and exhibited higher heat, emulsification and foaming stability. They also protected liver HepG2 cells against t-BHP-induced oxidative stress with enhanced glutathione synthesis in vitro. Furthermore, it was shown that GFPH induced upregulation of phase II enzyme expression, such as that of HO-1 and γ-GCL, via nuclear translocation of Nrf2 and phosphorylation of ERK. Taken together, these results demonstrate the potential of GFPH for use as a functional food ingredient with improved rheological and antioxidative properties.