Structural characteristics of purified beta-conglycinin from soybeans stored under four conditions.
Four storage conditions including adverse conditions [84% relative humidity (RH), 30 degrees C], mild conditions (57% RH, 20 degrees C), cold conditions (4 degrees C), and uncontrolled ambient conditions were used for storing soybeans. The storage time was 9 months for the adverse conditions and 18 months for the other three conditions. Beta-conglycinin was purified and characterized with respect to its molecular properties. After storage under the adverse conditions, beta-conglycinin showed no significant changes in total sugar content, surface hydrophobicity, free SH and SS bonds, and amino acid composition within 6 months; however, it showed a significant decrease in surface hydrophobicity and a significant increase in total free SH and total SH including SS content after 6 months. Analysis of the secondary structure showed a significant increase in alpha-helix content, but a significant decrease in beta-sheet content after 3 months. For the other three conditions, no significant changes occurred to the structures of beta-conglycinin when compared to the control. The molecular mass of beta-conglycinin remained in the range of 199-212 kDa for all conditions during the entire storage periods.
Hou
H J
HJ
Department of Cereal and Food Sciences, North Dakota State University, Fargo, North Dakota 58105, USA.
Chang
K C
KC
D000596:Amino Acids / Q000032:analysis; D052179:Antigens, Plant; D002241:Carbohydrates / Q000032:analysis; D004220:Disulfides / Q000032:analysis; D005916:Globulins / Q000737:chemistry* / Q000302:isolation & purification; D008970:Molecular Weight; D017433:Protein Structure, Secondary; D055314:Seed Storage Proteins; D030262:Soybean Proteins / Q000737:chemistry* / Q000302:isolation & purification; D013025:Glycine max / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000032:analysis
D000596:Amino Acids; D052179:Antigens, Plant; D002241:Carbohydrates; D004220:Disulfides; D005916:Globulins; D055314:Seed Storage Proteins; D030262:Soybean Proteins; D013438:Sulfhydryl Compounds; C013894:beta-conglycinin protein, Glycine max