An Improved Isolation Method of Soy beta-Conglycinin Subunits and Their Characterization

作者：Yuan De Bao; Min Wei; Yang Xiao Quan^*; Tang Chuan He; Huang Ke Li; Guo Jian; Wang Jin Mei; Wu Na Na; Zheng Heng Guang; Qi Jun Ru

来源：Journal of the American Oil Chemists' Society, 2010, 87(9): 997-1004.

DOI：10.1007/s11746-010-1583-0

• Subunits of beta-conglycinin
• Isolation
• Physicochemical characterization
• Thermal aggregation
• AFM

This study aimed at establishing an effective preparative isolation method of soy beta-conglycinin constituent subunits and characterizing some of their physicochemical properties and their heat-induced aggregation. These subunits were isolated in relatively large amounts and in high purity by dissociating beta-conglycinin in 6 M urea and using a combination of DEAE-Sepharose fast flow column chromatography and immobilized metal ion affinity chromatography (IMAC). At a pH deviating from isoelectric point (pI), zeta potentials of alpha' and alpha subunits were much larger than that of beta subunit, while in the latter case, the hydrophobic groups were more buried within the proteins. Dynamic light scattering analysis indicated that the extent of heat-induced aggregation of beta subunit was much higher than that of alpha' and alpha subunits, and the aggregation was also more affected by the increase in ionic strength. Atomic force microscopy analysis indicated that more ordered and stranded aggregates were formed for alpha' and alpha subunits. These results confirm a close relationship between physicochemical properties and heat-induced aggregation of beta-conglycinin subunits.

• 出版日期2010-9
• 单位福建省农业科学院; 华南理工大学