Proteolytic activity of Lactobacillus strains on soybean proteins

The capacity of Lactobacillus strains for degrading soy proteins was evaluated. The hydrolytic action was monitored by SDS–PAGE and reverse phase-HPLC analyses. Peptidase activities were also determined using synthetic chromogenic substrates. All assayed strains were able to hydrolyze α'-subunit of β-conglycinin while for the other fractions the degree of degradation was strain-dependent. The pattern of peptides produced from soy proteins hydrolysis differed amongst the lactobacilli studied, suggesting different proteolytic enzyme specificities.