A proteomics approach to characterizing limited hydrolysis of whey protein concentrate. (15th July 2021)

• Record Type: Journal Article
• Authors: Hinnenkamp, Chelsey; Ismail, Baraem P
• Is Part Of: Food chemistry. Volume 350(2021)
• Publication Date: 2021-07-15
• Subjects: ACE angiotensin converting enzyme -- α-CHCA α-cyano-4-hydroxy-cinnamic acid -- α-la α-lactalbumin -- β-lg β-lactoglobulin -- DDW double deionized water -- DH degree of hydrolysis -- DPP-IV dipeptidyl peptidase-IV -- DPPH 2, 2-diphenyl-picrylhydrazyl -- E:S enzyme-to-substrate ratio -- GMP glycomacropeptide -- GRAVY grand average of hydropathy -- HWPC hydrolyzed whey protein concentrate -- kDa kilodaltons -- MALDI-TOF matrix assisted laser desorption ionization -- MS mass spectrometry -- MBPDB Milk Bioactive Protein Database -- PTM post-translational modification -- PHWPC Protease M hydrolyzed whey protein concentrate -- SDS-PAGE sodium dodecyl sulphate-polyacrylamide gel electrophoresis -- SE-HPLC size exclusion -high performance liquid chromatography -- THWPC trypsin hydrolyzed whey protein concentrate -- WPC whey protein concentrate -- WPI whey protein isolate -- WPH whey protein hydrolysate -- UHPLC ultra-high performance liquid chromatography; Proteomics -- Whey protein hydrolysate -- Hydrophobic peptides -- Bioactive peptides; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2021.129235
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Whey protein concentrate was hydrolyzed by trypsin and an endo-/exopeptidase. Proteomics was used to characterize enzyme specificity and peptide differences. The combined endo-/exopeptidase activity released mostly hydrophilic peptides. The exopeptidase activity led to 9 shared bioactive peptides with trypsin. Proteomics can be used to efficiently optimize hydrolysis for targeted applications. Abstract: Whey Protein Concentrate was hydrolyzed by trypsin and Protease M, a novel endo/exopeptidase mix from Aspergillus oryzae . Protein peptide profiling demonstrated that Protease M preferentially hydrolyzed α-lactalbumin (α-la), while trypsin targeted β-lactoglobulin (β-lg). Peptide fractions were analyzed by liquid chromatography coupled with tandem mass-spectrometry to characterize differences in enzyme specificity, peptide hydrophobicity, and bioactivity, using bioinformatics tools. While trypsin cleaved at the C-terminal end of lysine and arginine, Protease M contributed to pepsin-like endopeptidase activity coupled with carboxyl, amino, and leucine exopeptidase activity, resulting in relatively more hydrophilic peptides compared to those released by trypsin hydrolysis. While trypsin and Protease M had varying specificity, 9 bioactive peptides were common among the hydrolysates, which was attributed to the exopeptidase activity of Protease M. The proteomics coupled with bioinformatics approach provided fundamental knowledge needed to optimize whey protein hydrolysis in a direct and efficient manner for targeted applications.