Premium
Acid adaptation to improve viability and X ‐prolyl dipeptidyl aminopeptidase activity of the probiotic bacterium Lactobacillus fermentum HA 6 exposed to simulated gastrointestinal tract conditions
Author(s) -
ChuKy Son,
Bui ThiKhanh,
Nguyen TienLong,
Ho PhuHa
Publication year - 2014
Publication title -
international journal of food science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.831
H-Index - 96
eISSN - 1365-2621
pISSN - 0950-5423
DOI - 10.1111/ijfs.12338
Subject(s) - lactobacillus fermentum , probiotic , lactic acid , bacteria , lactobacillaceae , biology , lactobacillus , microbiology and biotechnology , food science , fermentation , biochemistry , chemistry , lactobacillus plantarum , genetics
Summary In this work, the viability of the probiotic bacterium Lactobacillus fermentum HA 6 isolated from naturally fermented vegetables in Vietnam was improved by growing the bacterium into a mild acid condition ( pH 4.0). Viability and probiotic functionality [ X ‐prolyl dipeptidyl aminopeptidase (PepX) activity] of the acid‐adapted bacterium exposed to simulated gastrointestinal conditions were investigated. After 180 min in the simulated gastric juice (0.3 g/L pepsin, pH 2.0), the viability of acid‐adapted L . fermentum HA 6 (11.5%) was higher than that of control L . fermentum HA 6 (2.2%). Specific PepX activity of acid‐adapted cells (24.5 U/mg) was higher than that of control cells (17.8 U/mg). After 180‐min exposure to the simulated small intestinal medium (0.3 g/L bile salts, 0.1 g/L pancreatin, pH 8.0), the viability of acid‐adapted L . fermentum HA 6 (13.5%) was twofold as high as that of control L fermentum HA 6 (8.0%). Our results suggested that acid adaptation has a key role in acquiring cross‐protection mechanism, which in this study resulted in higher survival of L . fermentum HA 6 after simulated gastrointestinal stresses. The strategy of acid adaptation could be valuable for the production of robust probiotics.