Rapid screening and identification of novel dipeptidyl peptidase IV inhibitory peptides from buffalo milk

BACKGROUND

Peptidomics combined with molecular docking is an effective alternative method for rapid screening of novel bioactive peptides in food. Buffalo milk as a potential source of dipeptidyl peptidase-IV (DPP-IV) inhibitory peptides has been less studied. Peptidomics and molecular docking methods were employed to rapidly screen new DPP-IV inhibitory peptides from buffalo milk. The screened DPP-IV inhibitory peptides were further verified using an in vitro inhibition assay and a Caco-2 cell assay.

RESULTS

The DPP-IV inhibition rate of buffalo milk was increased from 73.40 ± 6.01% to 97.23 ± 3.18% in an in vitro digestion assay, suggesting that buffalo milk could be a promising source of DPP-IV inhibitory peptides. Subsequently, two novel peptides (GPFPIIV and FPQYL) with potential DPP-IV inhibitory activity were screened using peptidomics, molecular docking and an in vitro inhibitory assay. The IC₅₀ values for GPFPIIV and FPQYL were 0.2998 ± 0.03 and 0.1407 ± 0.01 mg mL⁻¹, respectively. During simulated gastrointestinal digestion in vitro, FPQYL had an excellent digestive stability of 92.13 ± 1.03%, whereas that of GPFPIIV was 59.52 ± 2.56%. In addition, GPFPIIV and FPQYL (1.00 mg mL⁻¹) showed significant DPP-IV inhibitory effects in a Caco-2 cell assay, with the inhibition rate increasing to 32% and 36%, respectively.

CONCLUSION

In summary, two new DPP-IV inhibitory peptides were screened from buffalo milk through a combination of peptidomics and molecular docking, both of which exhibited significant DPP-IV inhibitory activities. The identified peptides, GPFPIIV and FPQYL, have promising applications in diabetes management. © 2025 Society of Chemical Industry.