ISOLATION OF FABA BEAN LEGUMIN - A COMPARATIVE-STUDY OF VARIOUS METHODS

Different methods of legumin isolation from faba beans were compared w ith regard to the removal of vicilin taking into consideration the add itional influence of variety. SDS-PAGE, analytical ultracentrifugation and SE-HPLC were used for the analysis of protein composition. SDS-PA GE analysis of the isolated legumin samples revealed, that neither com bined salt fraction/isoelectric precipitation nor heating to 73 degree s C resulted in a complete removal of vicilin. Time-consuming isoelect ric zonal precipitation and heating at 83 degrees C as described by SC HLESIER et al. (Biochem. Physiol. Pflanzen 180 (1985) 225) provides le gumin preparations free of vicilin in low yields. Acceptable yields in shorter time were obtained by combining isoelectric precipitation/sal t fractionation with SCHLESIER'S procedure. SDS-PAGE analysis showed a certain dependence on variety of the patterns of legumin alpha-polype ptide chains.