Dipeptidyl peptidase IV inhibitory properties of a whey protein hydrolysate: Influence of fractionation, stability to simulated gastrointestinal digestion and food-drug interaction

作者：Nongonierma Alice B; FitzGerald Richard J^*

来源：International Dairy Journal, 2013, 32(1): 33-39.

DOI：10.1016/j.idairyj.2013.03.005

The in vitro dipeptidyl peptidase IV (DPP-IV) inhibitory activity of a whey protein hydrolysate (WPH) generated with a food-grade pancreatic enzyme preparation was studied. The 50% inhibitory concentration (IC50) value in the presence of WPH was 1.34 +/- 0.11 mg mL(-1). Ultrafiltration (UF) fractionation of WPH allowed enrichment in DPP-IV inhibitory peptides. The permeates generated by UF through 5 and 2 kDa membranes along with the hydrophilic fraction isolated by solid-phase extraction were significantly more potent DPP-IV inhibitors than WPH. Simulated gastrointestinal digestion of WPH resulted in an increased DPP-IV inhibitory potency (IC50 value of 1.02 +/- 0.05 mg mL(-1)). Competitive inhibition of DPP-IV was observed with WPH and all its fractions, indicating a direct interaction of the bioactive peptides therein with the active site of DPP-IV. Combinations of sitagliptin, a conventional drug-inhibitor of DPP-IV, and whey-derived peptides resulted in an additive effect on DPP-IV inhibition.

• 出版日期2013-9