Advertisement

Relationship between Rheological Properties and Conformational States of 7S Globulin from Soybeans at Acidic pH

  • Takao Nagano
  • Hiroyuki Mori
  • Katsuyoshi Nishinari

Abstract

We propose a simple method for isolating 7S and 11S globulins in high purity, and study the effects of pH on the rheological properties of the obtained 7S gel. Using this method, the heating differential scanning calorimetry (DSC) curve of each fraction shows only one endothermic peak. The storage modulus G’ of 7S globulin gel rapidly increased with decreasing pH below 5.5 – 6. Fourier transform infrared (FT-IR) measurements suggested that as pH fell below 5.5 – 6, 7S globulin tended to denature with heat, and the number of exposed β -strands increased. Thus, the number of intermolecular bonds which were available for the formation of gel networks increased, and a rigid gel formed at acidic pH.

Keywords

Rheological Property Endothermic Peak Storage Modulus Soybean Protein Seed Storage Protein 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    K. Saio and T. Watanabe, Difference in Functional Properties of 7S and 11S Soybean Proteins., J. Texture. Stud., 9:135 (1978).CrossRefGoogle Scholar
  2. 2.
    T. Nagano, M. Hirotsuka, H. Mori, K. Kohyama and K. Nishinari, Dynamic Viscoelastic Study on the Gelation of 7S Globulin from Soybeans., J. Agric. Food Chem., 40:941 (1992).CrossRefGoogle Scholar
  3. 3.
    V.H. Thanh and K. Shibasaki, Major Proteins of Soybean Seeds., J. Agric. Food Chem., 24:1117 (1976).CrossRefGoogle Scholar
  4. 4.
    S. Damodaran, Refolding of Thermally Unfolded Soy Proteins during the Cooling Regime of the Gelation Process: Effect on Gelation., J. Agric. Food Chem., 36:262 (1988).CrossRefGoogle Scholar
  5. 5.
    V.V. Suchkov, I.A. Popello, V.Y. Grinberg and V.B. Tolstogusov, Isolation and Purification of 7S and 11S Globulins from Broad Beans and Peas., J. Agric. Food Chem., 38:92 (1990).CrossRefGoogle Scholar
  6. 6.
    A. Dong, P. Huang and W.S. Caughey, Protein Secondary Structures in Water from Second Derivative Amide I., Biochemistry, 29:3303 (1990).CrossRefGoogle Scholar
  7. 7.
    H. Susi and D.M.Byler, Fourier Transform Infrared Study of Proteins with Parallel ß -chains., Arch. Biochem. Biophys., 258:465 (1987).CrossRefGoogle Scholar
  8. 8.
    M.C. Lawrence, E. Suzuki, J.N. Varghese, P.C. Davis, A.V. Donkelaar, P.A. Tulloch and P.M. Colman, The Three-dimensional Structure of the Seed Storage Protein Phaseolin.,EMBO J., 9:9 (1990).Google Scholar
  9. 9.
    J.J. Doyle, M.A. Schuler, W.D. Godette, V. Zenger and R.N. Beachy, The Glycosilated Seed Storage Proteins of Glycine max and Phaseolus vulgaris., J. Biol. Chem., 216:9228 (1986).Google Scholar
  10. 10.
    H. L. Casal, U. Kohler and H.H. Mantsch, Structural and Conformational Changes of ß - lactoglobulin B.,Biochim. Biophys. Acta,957:11 (1988).CrossRefGoogle Scholar
  11. 11.
    A.H. Clark, D.H.P. Saunderson and A. Suggett, Infrared and Laser-Raman Spectroscopic Studies of Thermally-induced Globular Protein Gels., J. Peptide Protein Res., 17:353 (1981).CrossRefGoogle Scholar
  12. 12.
    P.S. Kim and R.L. Baldwin, Intermediates in the Folding Reactions of Small Proteins., Annu. Rev. Biochem., 59:631 (1990).CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • Takao Nagano
    • 1
  • Hiroyuki Mori
    • 1
  • Katsuyoshi Nishinari
    • 2
  1. 1.Central Research Institute, Fuji Oil Co., Ltd.Yawara, Tsukuba-gunJapan
  2. 2.Department of Food and NutritionOsaka City UniversitySumiyoshi, OsakaJapan

Personalised recommendations