Identification of proteolytic bacteria from Yunnan fermented foods and their use to reduce the allergenicity of β-lactoglobulin

Beta-lactoglobulin is considered to be the major allergenic protein in milk. Lactic acid bacteria (LAB)  possess a protein hydrolysis system that holds great promise for hydrolyzing β-LG and reducing its allergenicity. Therefore, this study aimed to screen LAB with β-LG hydrolysis activity from Yunnan traditional fermented foods. The results showed that Pediococcus pentosaceus C1001, Pediococcus acidilactici E1601–1, and Lactobacillus paracasei E1601–2 could effectively hydrolyze β-LG and further reduce its sensitization (more than 40%). All 3 LAB hydrolyzed β-LG allergenic fragments V41–K60 and L149–I162. Moreover, they encode a variety of genes related to proteolysis, such as aminopeptidase pepC and pepN, proline peptidase pepIP and endopeptidase pepO; L. paracasei also E1601–2 contains extracellular protease coding gene prtP. They also encode a variety of genes associated with hydrolyzed proteins. The 3 strains screened in this study can be used to develop hypoallergenic dairy products.