Determination of the domain structure of the 7S and 11S globulins from soy proteins by XRD and FTIR

J Sci Food Agric. 2013 May;93(7):1687-91. doi: 10.1002/jsfa.5950. Epub 2012 Nov 14.

Abstract

Background: The 7S and 11S fractions from soybean proteins have interesting high nutritional and excellent functional properties. The aim of this research was to improve the functional properties of soy proteins by studying the effect of bis(2-ethylhexyl) sodium sulfosuccinate (AOT) reverse micelles on the conformation of the 7S and 11S globulins using Fourier transform infrared and X-ray diffraction spectroscopy.

Results: Fourier transform infrared revealed that the intensity of the 7S and 11S globulin bands from AOT reverse micelle extraction at 1600-1700, 1480-1575, 1220-1300, 3330, 1448 and 1395 cm(-1) was higher than from aqueous buffer. X-ray diffraction data showed that the intensities of 7S globulin using two extraction methods at 2θ about 10° were significantly different (P < 0.05), about 22° slightly increased. The intensities of 11S globulin at 2θ about 10° and 22° were similar. The average distance between particles (dhkl ) for 7S globulin with aqueous buffer extraction at 2θ about 10° was greater than AOT reverse micelle extraction.

Conclusion: This study showed the potential of reverse micelles as a protocol for extracting the 7S and 11S globulins for analytical purposes. The results represent a new avenue for determining the structures of the 7S and 11S globulins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Diet*
  • Dietary Proteins / analysis*
  • Functional Food*
  • Globulins / chemistry*
  • Glycine max / chemistry*
  • Humans
  • Micelles
  • Plant Proteins / chemistry*
  • Protein Structure, Tertiary
  • Soybean Proteins / chemistry*
  • Spectroscopy, Fourier Transform Infrared / methods
  • Succinates
  • X-Ray Diffraction / methods

Substances

  • 1,4-bis(2-ethylhexyl) sodium sulfosuccinate
  • Dietary Proteins
  • Globulins
  • Micelles
  • Plant Proteins
  • Soybean Proteins
  • Succinates