Di Zhao1,2,3,4, Lin Li5, Thao T Le6, Lotte B Larsen6, Dan Xu1, Wenjuan Jiao1, Bulei Sheng1, Bing Li1, Xia Zhang1. 1. College of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou, China. 2. Key Laboratory of Meat Processing, MOA, Nanjing Agricultural University, Nanjing, China. 3. Key Laboratory of Meat Processing and Quality Control, MOE, Nanjing Agricultural University, Nanjing, China. 4. Jiang Synergetic Innovation Center of Meat Production, Processing and Quality Control, Nanjing Agricultural University, Nanjing, China. 5. School of Chemical Engineering and Energy Technology, Dongguan University of Technology, Dongguan, China. 6. Department of Food Science, Aarhus University, Tjele, Denmark.
Abstract
BACKGROUND: Milk proteins are widely used in food production and are often glycated by reducing sugar. Although many studies have reported the digestibility of glycated milk protein, most have focused on measuring degree of hydrolysis (DH), showing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) image of digests. Detailed information on the changes in peptide composition of digests has seldom been revealed. Therefore, in addition to measuring the DH and showing the SGS-PAGE images of digests, we also analyzed the peptidomics in digests using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) and Mascot database in this work to further reveal the influence of glycation on protein nutrition. RESULTS: Compared with β-lactoglobulin and bovine serum albumin (BSA), DH of β-casein was suppressed to a lesser extent by glycation in both gastric and intestinal stages. Aggregates of glycated BSA were less sensitive to the action of digestive enzymes throughout gastrointestinal digestion according to SDS-PAGE images. Changes in the peptide composition of digests induced by glycation were distinctly displayed, showing both absence of peptides and occurrence of new peptides, based on the results obtained from LC-ESI-MS/MS. CONCLUSIONS: Glycation can greatly change the peptide composition in digests of milk protein. The nutritional impact of the change in the peptide composition requires further investigation, and the impact of MRPs in unabsorbed digests on the gut flora should be an interesting field for further studies.
BACKGROUND: Milk proteins are widely used in food production and are often glycated by reducing sugar. Although many studies have reported the digestibility of glycated milk protein, most have focused on measuring degree of hydrolysis (DH), showing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) image of digests. Detailed information on the changes in peptide composition of digests has seldom been revealed. Therefore, in addition to measuring the DH and showing the SGS-PAGE images of digests, we also analyzed the peptidomics in digests using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) and Mascot database in this work to further reveal the influence of glycation on protein nutrition. RESULTS: Compared with β-lactoglobulin and bovineserum albumin (BSA), DH of β-casein was suppressed to a lesser extent by glycation in both gastric and intestinal stages. Aggregates of glycated BSA were less sensitive to the action of digestive enzymes throughout gastrointestinal digestion according to SDS-PAGE images. Changes in the peptide composition of digests induced by glycation were distinctly displayed, showing both absence of peptides and occurrence of new peptides, based on the results obtained from LC-ESI-MS/MS. CONCLUSIONS: Glycation can greatly change the peptide composition in digests of milk protein. The nutritional impact of the change in the peptide composition requires further investigation, and the impact of MRPs in unabsorbed digests on the gut flora should be an interesting field for further studies.
Authors: Robert L Beverly; Robert K Huston; Andi M Markell; Elizabeth A McCulley; Rachel L Martin; David C Dallas Journal: J Nutr Date: 2020-04-01 Impact factor: 4.798