Separation and Identification of Glutamine Peptides from Defatted Soybean Meal by Enzymatic Hydrolysis

Abstract

Abstract:: Glutamine peptides were obtained from defatted soybean meal by enzymatic hydrolysis using a combination of Protamex® and trypsinase. The results showed that the extent of hydrolysis and the concentration of Gln peptides in the hydrolysate were 22.02% and 6.05 mmol/L, respectively. The hydrolysates were fractionated by size-exclusion chromatography on a Sephadex G-15 into five major fractions (GelF1–GelF5). The peptide (GelF1) fraction with the highest glutamine peptide content (51.8%) was further evaluated to determine its molecular weight distribution. Most (92.37%) peptides were less than 1 000 Da. Glutamic acid and glutamine were the most abundant amino acids, accounting for up to 12.98% of the total amino acid content. In addition, the total amino acid content in GelF1 was higher than that in GelF2 and GelF3.Supported by National Key R&D Program of China (2016YFD0400203). Keywords:: Defatted soybean meal hydrolysates, Glutamine peptides, Chromatographic separation, Amino acid analysis