Ultrastructure of Consecutively Extracted and Flocculated Gliadins and Glutenins

• Published in: Journal of cereal science 1998-01, Vol.27 (1), p.27-36
• Main Authors: Shomer, Ilan, Lookhart, George L., Vasiliver, Rosa, Bean, Scott
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; biochemical techniques; Biological and medical sciences; Cereal and baking product industries; chemical structure; cultivars; electrophoresis; flocculation; Food industries; fractionation; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; gliadin; gliadin, gluten, capillary electrophoresis, transmission electron microscopy, microstructure, ultrastructure; glutenins; Triticum aestivum; ultrastructure; Varietal selection. Specialized plant breeding, plant breeding aims; wheat flour; winter wheat; Yield, quality, earliness, varia
• ISSN: 0733-5210; 1095-9963
• DOI: 10.1006/jcrs.1997.0143

Gliadin and glutenin are characterized by specific ultrastructures, which depend on variety and separation conditions. Gliadins, extracted with 80% ethanol, of Israeli spring wheat ‘Ariel’ appeared as spherical bodies within an amorphous perforated matrix. The gliadins of a commercial sample of U.S. hard red winter wheat were deposited in bundles of bodies of concentric membrane-like units during water dialysis and they tended to separate while heating at 120 °C. Acetic-acid-extracted glutenins heated at 120 °C appeared as amorphous compact agglomerated particles beside dispersed aggregates, fibril-like patterns and oil-like bodies. The extracted glutenins, which were dialysed vs water, appeared as dispersed or aggregated particles beside oil-like bodies embedded in and/or encapsulated by coagulated protein. Differences were found in high-performance capillary electrophoresis patterns of both gliadins and glutenins between the Israeli spring wheat ‘Ariel’ and the good baking quality U.S. hard red winter wheat ‘Karl 92’; indicating that the structural differences are a result of different proteins and differences in the physicochemical properties of the proteins.