Reduction of Inmunoreactivity of soy milk proteins by fermentation with proteolytic lactic acid bacteria

BISCOLA V.; RODRIGUEZ DE OLMOS A.; CHOISET Y.; RABESONA H; CHOISOONGNERN T.; DROUET M.; MOZZI F.; GARRO M.S.; FRANCO B.D.G.M.; HAERTLE T.

Belgrado

Conferencia; First International Conference. Improving Allergy Risk Assessment Strategy for new food proteins (ImpARAS).; 2015

University of Belgrade

Soybean is a source of proteins with high nutritional value and represents an alternative for protein intake to vegetarians, lactose-intolerant and allergic to bovine milk individuals. Besides, its consumption has been associated with health benefits. However, soybean proteins can also trigger adverse symptoms in allergenic individuals. The main proteins responsible for soybean allergy are β-conglycinin (7S) and glycinin (11S); an alternative to reduce the binding of these immunoreactive proteins with specific IgE from allergic patients is the fermentation of soy products with proteolytic lactic acid bacteria (PLAB) able to hydrolyze the main epitopes present in the 7S and 11S fractions. The aim of this study was to evaluate the protein hydrolysis extension caused by fermentation of soy milk with PLAB and the reduction in the immunoreactivity of the obtained hydrolysates. The proteolytic strain Enterococcus faecalis 43 was used to carry out the fermentations and the hydrolysis extension was observed after SDS-PAGE technique. Reversed-Phase HPLC was used to evaluate the peptide profiles obtained after hydrolysis and the immunoreactivity of hydrolyzates was assessed by competitive ELISA, using sera from soya protein allergic patients. E. faecalis 43 was able to partially hydrolyze the α, α? and β fractions of soy milk β- conglycinin, and both basic and acidic fractions of glycinin. RP-HPLC analysis of hydrolyzates showed the appearance of less hydrophobic peptides in fermented samples and confirmed the results observed with SDS-PAGE. A reduction in the binding capability of the hydrolysates to the IgE present in the sera of allergic patients using competitive ELISA was observed. These results indicate that soy milk fermentation by E. faecalis 43 may reduce the in vitro immunoreactivity of soya proteins suggesting that this PLAB strain presents an interesting potential for its application in the production of hypoallergenic soy products.