Purification and characterization of calcium-binding soybean protein hydrolysates by Ca2+/Fe3+ immobilized metal affinity chromatography (IMAC)

Food Chem. 2013 Dec 1;141(3):1645-50. doi: 10.1016/j.foodchem.2013.04.113. Epub 2013 May 9.

Abstract

Soybean protein hydrolysates (SPHs) can bind calcium in order to form soluble peptide-calcium complexes. However, amino acid composition and structural characteristics of the calcium chelating SPHs are still unclear. This study separated SPHs with calcium and iron immobilized metal affinity chromatography (IMAC), and examined the effects of SPHs with different amino acid composition on calcium binding capacity. Three fractions (FFe-1, FFe-2 and FFe-3) isolated with IMAC-Fe(3+) were shown possessing increased Glu, Gln, Lys and Pro content from FFe-1 to FFe-3, and improved amount of bound calcium. Furthermore, the fractions adsorbed on IMAC-Ca(2+) (Fe(3+)) were separated and identified with reverse-phase (RP)-HPLC and MALDI-TOF MS/MS. The results showed that the sequence of peptides from FCa-2 and FFe-3 fractions was DEGEQPRPFPFP.

Keywords: Amino acid composition; Calcium binding; Characterization; IMAC; Purification; Soybean protein hydrolysates.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Amino Acid Sequence
  • Calcium / chemistry
  • Calcium-Binding Proteins / chemistry
  • Calcium-Binding Proteins / isolation & purification*
  • Chromatography, Affinity / instrumentation
  • Chromatography, Affinity / methods*
  • Glycine max / chemistry*
  • Iron / chemistry
  • Molecular Sequence Data
  • Peptide Mapping
  • Protein Binding
  • Protein Hydrolysates / chemistry*
  • Protein Hydrolysates / isolation & purification
  • Soybean Proteins / chemistry
  • Soybean Proteins / isolation & purification*

Substances

  • Calcium-Binding Proteins
  • Protein Hydrolysates
  • Soybean Proteins
  • Iron
  • Calcium