关键词: 大豆 7S 球蛋白, 葡聚糖, 物化性质, 大分子拥挤体系, Maillard 反应

Abstract: Two kinds of β-conglycinin-dextran conjugates were prepared respectively in the macromolecular crowding environment or via the dry-heating method，and then a comparison was made in their physicochemical property． On the basis of the solubility of glycation products at the isoelectric point of β-conglycinin (pH =4. 8) or under the neutral condition (pH =6. 5)，the products were separated into two components，and then a discussion was conducted about the graft degree，secondary structure，internal fluorescence and turbidity of the two components．The results show that (1) β-conglycinin in the macromolecular crowding and liquid phase environment is hydrolyzed to a certain degree，with small peptide chains being produced，which is beneficial to the covalent access of polysaccharide; (2) MC48 obtained at pH4. 8 in the macromolecular crowding environment，is mainly the glycation product of high graft degree，while MC65 obtained at pH6. 5 in the macromolecular crowding environment，contains the glycation products of both low and uneven graft degree; and (3) DH48 and DH65 obtained respectively at pH4. 8 and pH6. 5 via the dry-heating method，are of low graft degree，and their difference is less significant than that in the macromolecular crowding environment． Moreover，it is found from SDA-PAGE，CD and intrinsic fluorescence emission spectra that there exists a significant difference in physicochemical property between MC48 and MC65，while an insignificant difference between DH48 and DH65．

Key words: β-conglycinin, dextran, physicochemical properties, macromolecular crowding environment, Maillard reaction