Soymilk fermentation by Enterococcus faecalis VB43 leads to reduction in the immunoreactivity of allergenic proteins β-conglycinin (7S) and glycinin (11S)

CHOISET, Y.; MOZZI, F.; HAERTLÉ, T.; DE OLMOS, A. RODRIGUEZ; GARRO, M.S.; DROUET, M.; BISCOLA, V.; RABESONA, H.; CHOBERT, J.-M.; FRANCO, B.D.G.M.

Beneficial Microbes

Wageningen Academic Publishers

Año: 2017 vol. 8 p. 635 - 643

1876-2883

Food allergies represent a serious problem affecting human health and soy proteins rank among the most allergenic proteins from food origin. The proteolytic enzymes produced by Lactic Acid Bacteria (LAB) can hydrolyze the major allergens present in soybean, reducing their immunoreactivity. Even though many studies have discussed the ability of LAB to ferment soy-based products, the great majority of them focus on the improvement of the sensory characteristics and functionality of proteins and there is a lack of information about the role of lactic fermentation in the reduction of immunoreactivity of soy proteins. The aim of the present study was to evaluate the capability of the proteolytic strain Enterococcus faecalis VB43 to hydrolyze the main allergenic proteins present in soymilk and to evaluate the immunoreactivity of the hydrolysates after soymilk fermentation with this strain. Results obtained by SDS-PAGE of fermented soymilk demonstrated complete hydrolysis β-subunit from β-conglycinin and the acidic polypeptide from glycinin. RP-HPLC analysis of the peptides released after hydrolysis revealed the formation of new peptides, followed by the disappearance of the peaks representing non-hydrolyzed proteins, indicating extensive hydrolysis of the substrate. Results from competitive ELISA tests clearly indicated a reduction in the immunoreactivity of fermented sample, by more than one logarithmic unit in comparison to non-fermented control, suggesting that soymilk fermented by E. faecalis 43VB possess lower capacity to induce allergic responses in sensitive individuals. Therefore, the obtained results suggest that E. faecalis VB43 is efficient in the reduction of the immunoreactivity of soymilk proteins.