Evaluation of enzyme efficiency for soy oleosome isolation and ultrastructural aspects

Two procedures and four commercial enzymes were compared to isolate intact oleosomes from dry soybean flour. Results showed that Multifect® Pectinase FE efficiently liberated intact oleosomes in both procedures. The increase in oleosome extraction yield and reducing sugar production indicates that there was a synergistic effect on degrading the cell wall when theses enzymes were used together. In the control with no enzymes, 34.06% and 67.66% of the total soybean oil were obtained from oleosomes, respectively, with the initial and the simplified procedures which mimics the initial procedure, but using less buffer. Transmission electron micrographs of extracts from the simplified procedure showed intact oleosomes, indicating that the extraction conditions did not affect oleosome integrity. Native soybean proteins were recovered from the aqueous supernatant in addition to the oleosome fraction. Using Multifect® Pectinase FE resulted in the disappearance of the α′ and α subunits of the β-conglycinin.