Intestinal health benefits of bovine whey proteins after simulated gastrointestinal digestion

Bovine whey proteins are widely incorporated in foods for their nutritional, health promoting and functional value. However, whey proteins are readily digested in the upper gut. The objective of this study was to determine the fate and bioactivity of bovine whey proteins post simulated gastrointestinal digestion (GID). Our results demonstrated that beta-lactoglobulin and alpha-lactalbumin post GID protect human intestinal cells from free radical formation. Post GID, lactoferrin significantly increased the amount of the intracellular antioxidant enzymes superoxide dismutase 1, 2 and thioredoxin. In addition, all whey samples post GID inhibited the activity of the dipeptidyl peptidase IV. However, the conditions of the gut destroyed the ability of whey proteins to act as glucagon-like peptide-1 secretagogues. The peptide profiles of GID whey protein isolate, beta-lactoglobulin, alpha-lactalbumin, bovine serum albumin and lactoferrin revealed several peptides with bioactive potential.