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

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 degrees C), enzyme to substrate (E:S) ratio (0.50-2.00% (w/w)) and time (60-240 min)). 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) mg mL(-1) were produced. Camel and bovine milk proteins hydrolysed at 40 degrees C, 1.8% E:S and 218 min had DPP-IV IC50 values of 0.68 +/- 0.08 and 0.85 +/- 0.10 mg mL(-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. (C) 2017 Elsevier Ltd. All rights reserved.