title: Quantification of bio- and techno-functional peptides in tryptic bovine micellar casein and β-casein hydrolysates.
abstract: Numerous peptides generated by triptic hydrolysis of micellar casein and β-casein from bovine milk have been reported to exhibit bio-functional or techno-functional activities. In this study, the focus was placed on the quantification of eleven potential functional peptides generated by enzymatic hydrolysis with trypsin. The identity of the target peptides was verified by LC-ESI-MS/MS and a reverse phase high performance liquid chromatography method (RP-HPLC) was established to quantify the peptides. The quantification was based on calibration curves drawn using synthesised purified peptides. The regression analysis comparing >30 standard measurements of each peptide standard showed a regression coefficient R(2)>0.9958. The inter-day repeatability of the quantification method was always within a relative error of 0.2-6.5%, while the relative error of the accuracy for reproducibility was in the range of 0.1-2.4%. The established method was successfully applied for the quantitative analysis of the eleven functional peptides in different dairy fractions generated by cross-flow ultrafiltration.
authors.affiliation: Institute of Food Science and Biotechnology, Department of Dairy Science and Technology, University of Hohenheim, 70599 Stuttgart, Germany. Electronic address: aline.holder@uni-hohenheim.de.
authors.forename: Aline
authors.initials: A
authors.lastname: Holder
authors.affiliation: Institute of Food Science and Biotechnology, Department of Dairy Science and Technology, University of Hohenheim, 70599 Stuttgart, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Thienel
authors.affiliation: Proteomics Core Facility Life Science Centre, University of Hohenheim, 70599 Stuttgart, Germany.
authors.forename: Iris
authors.initials: I
authors.lastname: Klaiber
authors.affiliation: Proteomics Core Facility Life Science Centre, University of Hohenheim, 70599 Stuttgart, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Pfannstiel
authors.affiliation: Institute of Food Science and Biotechnology, Department of Food Physics and Meat, University of Hohenheim, 70599 Stuttgart, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Weiss
authors.affiliation: Institute of Food Science and Biotechnology, Department of Dairy Science and Technology, University of Hohenheim, 70599 Stuttgart, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Hinrichs
mesh_terms: D000818:Animals; D002364:Caseins / Q000737:chemistry*; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D010455:Peptides
chemical_list: D002364:Caseins; D010455:Peptides; C475729:casein hydrolysate
keywords: Casein; Enzymatic hydrolysis; Mass spectrometry; Peptide fractions; Quantification; RP-HPLC