Abstract:To promote efficient utilization of chicken bones and development of novel antioxidants, antioxidant peptides were generated from chicken bone meal fermented with Bacillus licheniformis. First, the effect of glucose addition on Bacillus licheniformis growth was examined. Next, fermentation conditions were optimized using single-factor experiments and response surface methodology. Tricine-SDS-PAGE was simultaneously performed on the chicken bone fermentation broth. Finally, the chicken bone peptides in the fermentation broth were separated using an organic membrane, and their antioxidant activities were determined. The addition of glucose inhibited B. licheniformis growth. The optimal fermentation conditions were as follows: 4.2% (m/m) of chicken bone meal, initial pH of 6.0, 4.0% (v/v) of bacterial inoculum, working volume of 50 mL in a 250 mL flask, and fermentation time of 24 h. These conditions yielded 56.29% hydrolysis in the fermentation broth, and the DPPH• scavenging rate reached 57.11%. Tricine-SDS-PAGE results verified that the chicken bone meal was hydrolyzed. Among the antioxidant peptide fractions obtained by organic membrane separation, fraction V (with a molecular weight of 3~5 kDa) exhibited the highest antioxidant activity. Its respective DPPH, superoxide anion, and ABTS+ scavenging activities were 59.08%, >20.21%. and 85%, respectively. This study lays a foundation for increasing the overall utilization value of chicken bones and expands the scope of research and development of functional products.