Waste valorization of chicken skin as a promising source of bioactive peptides using in silico approaches

The poultry meat industry generates considerable amounts of chicken waste, which may contain valuable bioactive compounds. This study employed in silico simulations to identify bioactive compounds from chicken waste. Protein sequences of chicken skin, including collagen type I, collagen type III, elastin, and keratin, were retrieved from the UniProt database. Sequence alignment revealed high similarity between chicken, bovine, and porcine collagen, with up to 90 % identity. Bioactivity analysis indicated that chicken skin can be a good source of bioactive peptides (A ≥ 0.500). Protein hydrolysis using a combination of plant-based proteases achieved a high degree of hydrolysis (DHt) at 71.76 %, with the highest potential for generating bioactive peptides observed for papain on collagen type III. Proteolysis simulation indicated that peptides released from chicken skin proteins may exhibit dipeptidyl peptidase-IV (DPP-IV) inhibitory, angiotensin-converting enzyme (ACE) inhibitory, antithrombotic, and antiamnestic activities. The peptides predicted to have high bioactivity potential included WF, MF, CF, PF, WG, QF, MG, NF, PPG, KF, PG, WK, MR, YPG, PL, PR, PY, YG, PPK, IP, MKG, and IG. After evaluation of their toxicity, physicochemical, and pharmacokinetic properties, the peptides WF, MF, MG, QF, PG, PY, YG, and IG were selected for molecular docking analysis. Molecular docking results demonstrated considerable binding affinities for the following complexes: DPP-IV-WF (−8.3 kcal/mol), DPP-IV-QF (−7.4 kcal/mol), DPP-IV-MF (−4.8 kcal/mol), ACE-YG (−7.3 kcal/mol), ACE-MF (−5.1 kcal/mol), acetylcholinesterase (AChE)-PG (−6.3 kcal/mol), and thrombin-PG (−5.3 kcal/mol). The findings of this in silico prediction study suggest that chicken skin could be a promising source for enzymatically producing bioactive peptides with inhibitory activity against human ACE, DPP-IV, thrombin, and AChE.