Enzymatic Hydrolysis Does Not Reduce the Biological Reactivity of Soybean Proteins for All Allergic Subjects

• Published in: Journal of agricultural and food chemistry Vol. 63; no. 43; pp. 9629 - 9639
• Main Authors: Panda, Rakhi, Tetteh, Afua O, Pramod, Siddanakoppalu N, Goodman, Richard E
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 04.11.2015
• Subjects: allergenicity; beta-conglycinin; blood serum; bromelains; chymotrypsin; Chymotrypsin - chemistry; enzymatic hydrolysis; Food Hypersensitivity - immunology; food quality; functional foods; Glycine max - chemistry; Glycine max - immunology; Humans; Hydrolysis; immunoglobulin E; Immunoglobulin E - analysis; Immunoglobulin E - immunology; leukemia; liquid chromatography; papain; patients; protein isolates; rats; soy protein; Soybean Proteins - chemistry; Soybean Proteins - immunology; subtilisin; Subtilisins - chemistry; tandem mass spectrometry; trypsin; Trypsin - chemistry; soybean; functional assay; IgE binding; enzymatic hydrolysis
• ISSN: 0021-8561; 1520-5118; 1520-5118
• DOI: 10.1021/acs.jafc.5b02927

Many soybean protein products are processed by enzymatic hydrolysis to attain desirable functional food properties or in some cases to reduce allergenicity. However, few studies have investigated the effects of enzymatic hydrolysis on the allergenicity of soybean products. In this study the allergenicity of soybean protein isolates (SPI) hydrolyzed by Alcalase, trypsin, chymotrypsin, bromelain, or papain was evaluated by IgE immunoblots using eight soybean-allergic patient sera. The biological relevance of IgE binding was evaluated by a functional assay using a humanized rat basophilic leukemia (hRBL) cell line and serum from one subject. Results indicated that hydrolysis of SPI by the enzymes did not reduce the allergenicity, and hydrolysis by chymotrypsin or bromelain has the potential to increase the allergenicity of SPI. Two-dimensional (2D) immunoblot and liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis of the chymotrypsin-hydrolyzed samples indicated fragments of β-conglycinin protein are responsible for the apparent higher allergenic potential of digested SPI.