title: Role of intestinal brush border peptidases in the simulated digestion of milk proteins.
abstract: METHODS
  This study aimed to assess the impact of the "often neglected" intestinal brush border membranes (BBMs) hydrolases on dietary peptides, exploring the possibility that the disintegration of proteins progressed in the small intestine up to a "core" of intrinsically stable oligopeptides, persisting independently on the up-stream breakdown.
  
  
  RESULTS
  Samples of sodium caseinate, skim milk powder, and whey protein isolate were submitted to in vitro simulated gastropancreatic digestion using two different procedures: (i) a simplified model involving the main compartmental specific proteases; (ii) a static digestion method based on a frameset of parameters inferred from in vivo. The gastroduodenal digesta were further hydrolyzed with peptidases from porcine jejunal BBM. The peptidomes arising from the two digestion models, characterized by combined HPLC and MS techniques, differed to some extent. However, only specific protein domains survived digestion, among which are potential bioactive or immunogenic (food allergy) peptides. The degree of hydrolysis (DH) after BBM digestion (70-77%) practically did not differ between the digestion models and significantly increased the DH after duodenal steps.
  
  
  CONCLUSIONS
  Any in vitro digestion model should be supplemented with a jejunal phase to realistically determine the bioaccessibility and bioavailability of dietary peptides.
authors: Istituto di Scienze dell'Alimentazione-Consiglio Nazionale delle Ricerche, Avellino, Italy.
authors: Gianluca
authors: G
authors: Picariello
authors: Beatriz
authors: B
authors: Miralles
authors: Gianfranco
authors: G
authors: Mamone
authors: Laura
authors: L
authors: Sánchez-Rivera
authors: Isidra
authors: I
authors: Recio
authors: Francesco
authors: F
authors: Addeo
authors: Pasquale
authors: P
authors: Ferranti
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D004063:Digestion; D007583:Jejunum / Q000201:enzymology*; D008871:Microvilli / Q000201:enzymology*; D008894:Milk Proteins / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000502:physiology*; D013552:Swine
chemical_list: D008894:Milk Proteins; D010447:Peptide Hydrolases
keywords: Brush border membrane hydrolases; Degree of hydrolysis; Gastrointestinal digestion; In vitro digestion models; Milk proteins