Advanced Utilization of By-Product from the Sturgeon Aquaculture Industry: Optimum Preparation of Notochord-Derived Multifunctional Peptides by Glycation using the Maillard Reaction

Purpose Sturgeon notochord, a by-product in the sturgeon aquaculture industry, is a promising yet underutilized source of type II collagen. In this study, functionally enhanced collagen peptides (CPs) were developed from notochordal collagen using optimal glycation via the Maillard reaction, and the potential applications of the by-product and possible contributions to the valorization of the sturgeon aquaculture industry were determined. Methods CP prepared by papain digestion was mixed with alginate oligosaccharide (AO), glucose (Glu), or glucuronic acid (GluA), lyophilized, and then glycation at 80 °C and 75% relative humidity for up to 8 h. Amino acid analysis was performed to evaluate the formation of glycated CP (CP–sugars). The health-beneficial functions, antioxidative and anti-inflammatory activities of CP–sugars were evaluated by the ABTS radical scavenging assay and by quantification of inflammatory compound (tumor necrosis factor-α and nitric oxide) production in LPS-stimulated macrophages, respectively. Results During the glycation process, reducing sugars were reacted with lysine and arginine in CP. GluA had a higher reactivity to the reactive amino acids than that of Glu and AO. The antioxidant and anti-inflammatory functions of CP–sugars were increased with the glycation processes, and AO-glycation enhanced the health-beneficial functions of CP without a marked loss of reactive amino acids compared with the Glu- and GluA-glycations. Conclusion The appropriate glycation via the Maillard reaction is an effective way to simultaneously enhance the antioxidant and anti-inflammatory functions of CP from sturgeon notochord to facilitate its application as a functional food material. Graphical Abstract