Response surface methodology optimization on extraction and antioxidant activity evaluation of antioxidant peptide from enzymatic hydrolysates of sturgeon bone

Free radicals can pose health risks and reduce food quality when accumulated excessively. Fish byproducts, often underutilized, offer a valuable opportunity for extracting bioactive peptides with antioxidant activities. This study aimed to optimize the conditions for extracting antioxidant peptides from sturgeon bone using response surface methodology. The findings revealed that trypsin was the most effective protease for hydrolyzing sturgeon vertebra. The optimization conditions were determined as follows: a solid-liquid ratio of 1:21.90, enzyme concentration of 1167.31 U/g, and time of 4.25 h. Under these conditions, the DPPH free radical scavenging rate and the reducing power were 25.92% and 0.83 respectively. Enzymatic hydrolysates were abundant in amino acids associated with antioxidant function. Notably, peptides with molecular weights below 3 KDa showed the highest antioxidant properties. The present study emphasizes the potential of peptides derived from sturgeon bone as natural antioxidants, contributing to resource utilization and development of functional foods and pharmaceuticals.