Improvement of the Nutritional Value of Soybean [Glycine max (L) Merr.] Seed with Alteration in Protein Subunits of Glycinin (11S Globulin) and b-conglycinin (7S Globulin)

Authors : Behzad KAVIANI, Ardashir KHARABIAN

Pages : 91-97

View : 14 | Download : 9

Publication Date : 2008-12-01

Article Type : Research Paper

Abstract :Protein quality in soybean seeds is strongly influenced by nutritional conditions. Glycinin insert ignore into journalissuearticles values(11S globulin); and b-conglycinin insert ignore into journalissuearticles values(7S globulin); are the 2 main proteins in soybean seeds. Protein quality of glycinin insert ignore into journalissuearticles values(11S); is higher than that of b-conglycinin insert ignore into journalissuearticles values(7S);, due to the presence of higher amounts of s-containing amino acids insert ignore into journalissuearticles values(methionine and cysteine); in glycinin than b-conglycinin. Of the amino acids in glycinin, 3%-4.5% are methionine and cysteine but these important amino acids are not found in b-conglycinin insert ignore into journalissuearticles values(especially b-subunit);. Pot studies were conducted with soybean [Glycine max insert ignore into journalissuearticles values(L); Merr.] grown under various levels of KCl and CaHPO4 and the effects of salts insert ignore into journalissuearticles values(fertilizers); on glycinin and b-conglycinin subunits were evaluated. Abundance of glycinin subunits insert ignore into journalissuearticles values(high quality); and b-conglycinin insert ignore into journalissuearticles values(poor quality); was determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis insert ignore into journalissuearticles values(SDS-PAGE);. Quantitative changes in total protein insert ignore into journalissuearticles values(cytosolic protein); were determined by the Lowry test. Some significant differences were recognized between the measured factors and various treatments. The highest amount of total protein insert ignore into journalissuearticles values(%); and acidic subunit of glycinin containing more methionine and cysteine was observed in seeds of plants grown in the soil treated with 30 g of KCl and 0.02 g of CaHPO4 per 100 kg of soil. A lower amount of protein was observed when no fertilizer insert ignore into journalissuearticles values(0 P and 0 K); was applied in the growth medium. The current study showed that improvement of soybean nutritional value can be achieved by increasing the content of 11S proteins and decreasing 7S proteins.
Keywords : b conglycinin, electrophoretic pattern, fertilizer, glycinin, soybean, seed storage protein