Ion exchange chromatographic conditions for obtaining individual subunits of soybean β-conglycinin

Soybean β-conglycinin is a complex protein possessing health-promoting properties. β-Conglycinin is a trimeric glycoprotein. Little information related to methods for separation of the individual chains forming β-conglycinin has been so far published and it is of great interest. As a consequence, less data on the bioactivities of α, α′ and β subunits of this glycoprotein have been published. The present research aimed to find out new alternative chromatographic conditions to obtain β-conglycinin subunits that are free of contaminating proteins. In the present short communication, we propose the use of a two-step ion exchange chromatographic protocol to achieve this goal. Firstly, β subunit was separated by means of anionic exchange fast protein liquid chromatography. Secondly, α and α′ chains were separated from each other by cationic exchange. Our data indicated the feasibility of proposed fractionation protocol to separate soybean β-conglycinin α and α′ subunits from other contaminating proteins and to obtain enough amounts of the three individual chains forming this glycoprotein for further characterization and application. The procedure may be easily up-scaled.