Dipeptidyl peptidase IV (DPP-IV) inhibitory properties of camel milk protein hydrolysates generated with trypsin

Abstract

Dipeptidyl peptidase IV (DPP-IV) inhibitory peptides were identified in silico within camel milk proteins. Camel milk was hydrolysed with trypsin using a design of experiments (DOE, temperature (40–60°C), enzyme to substrate (E:S) ratio (0.50–2.00% (w/w)) and time (60–240min)). Fifteen hydrolysates (H1–H15) having DPP-IV half maximal inhibitory concentration (IC50) values between 0.52±0.06 (H9) and 1.26±0.13 (H1) mgmL−1 were produced. Camel and bovine milk proteins hydrolysed at 40°C, 1.8% E:S and 218min had DPP-IV IC50 values of 0.68±0.08 and 0.85±0.10mgmL−1 (p<0.05), respectively. Potent and unique DPP-IV inhibitory peptides (Leu-Pro-Val-Pro-Gln and Trp-Lys) were identified in camel milk protein hydrolysates, which were not present in bovine milk protein hydrolysates. The DPP-IV inhibitory properties of camel milk peptides were reported for the first time in this study. Camel milk is an interesting substrate to further investigate for its antidiabetic potential.