Cereal Chem 61:76 - 82.  |  VIEW ARTICLE
Gel Filtration and Characterization of Neutral Salt Extracted Wheat Gluten Proteins Varying in Hydrophobic Properties.

K. R. Preston. Copyright 1984 by the American Association of Cereal Chemists, Inc. 

Defatted gluten proteins, extracted separately with various concentrations of simple monovalent sodium salts of the lyotropic series (F, Cl, Br, ClO4, I, SCN) were fractionated by gel filtration of Sephacryl S-300. Four fractions with apparent average molecular weights greater than 300,000, 38,000, 18,000, and 14,500, as well as a low molecular weight fraction, were characterized by electrophoresis and amino acid analysis. Large differences both the quantitative and qualitative properties of the extracts due to anion type and concentration were obtained. With 1.0M nonchaotropic salts, low molecular weight gliadinlike proteins and high molecular weight gluten proteins with high charge densities were extracted, indicating that these fractions had a low tendency to interact hydrophobically. As the chaotropic nature of the salts was increased, the 38,000 molecular weight gluten fraction with gliadinlike properties became extractable, suggesting that this fraction had a strong tendency to undergo interprotein hydrophobic interactions. High concentrations of the most chaotropic salt, NaSCN, were required to extract the gluteninlike high molecular weight fraction, indicating a very strong tendency to interact hydrophobically.