Utilization of feather keratin waste to antioxidant and migration-enhancer peptides by Bacillus licheniformis 8-4

Aims Feathers are keratin-rich byproducts of poultry processing, but those are often frequently abandoned as garbage and thus polluting the environment. Therefore, the study focused on the efficient biodegradation, bioactivity, and high-value application of feather keratin. Methods and results Feather-degrading bacteria were identified, and the degradation properties were characterized. DPPH (1,1-Diphenyl-2-picrylhydrazyl radical) and ABTS (2,2 '-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid))radical scavenging assays, cytotoxicity assays, intracellular reactive oxygen scavenging assays, and cell migration assays were used to examine the biological activities of the feather keratin hydrolysis peptides (FKHPs). The results showed that we screened a feather-degrading strain of Bacillus licheniformis 8-4, which achieved complete degradation of 2% (w/v) feathers within 48 h. Notably, the feather fermentation broth was particularly high in FKHPs, which exhibited good DPPH and ABTS radical scavenging ability. Further studies revealed that FKHPs had both the ability to scavenge H2O2-induced ROS from HaCat cells and the ability to promote HaCat cell migration, while remaining non-toxic. Conclusions The effective feather-degrading ability of B. licheniformis 8-4 allowed for the fermentation of feather medium to yield active peptides that were both antioxidants and cell-migration enhancers.

Automated summary

This study aimed to efficiently degrade, evaluate the bioactivity, and explore the potential applications of feather keratin. A feather-degrading strain of Bacillus licheniformis 8-4 was identified, which completely degraded 2% (w/v) feathers within 48 h. The resulting feather fermentation broth was rich in feather keratin hydrolysis peptides (FKHPs) with good antioxidant and cell migration-enhancing abilities, and no toxicity was observed.