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Co‐cultivation of a bacteriocin‐producing mixed culture of Bifidobacterium thermophilum RBL67 and Pediococcus acidilactici UVA1 isolated from baby faeces
Author(s) -
Mathys S.,
Meile L.,
Lacroix C.
Publication year - 2009
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1111/j.1365-2672.2009.04186.x
Subject(s) - pediococcus acidilactici , bacteriocin , probiotic , antimicrobial , pediococcus , microbiology and biotechnology , biology , food science , bifidobacterium , bacteria , lactobacillus , fermentation , lactic acid , genetics , lactobacillus plantarum
Aims: We investigated the kinetics of growth, metabolism and antimicrobial activity of Bifidobacterium thermophilum RBL67 and Pediococcus acidilactici UVA1 previously isolated as a consortium from human baby faeces and producing antimicrobial proteinaceous compounds. Methods and Results: Cell growth, antimicrobial activity, glucose consumption, organic acid production and pediocin‐gene expression were monitored during pure and mixed strain batch cultures with controlled pH (6·0) at 37°C. The balance of the two strains in mixed cultures was stable, yielding high cell count of 10 9 CFU ml −1 after a very short incubation time of 4 h for UVA1 and 7 h for RBL67, and RBL67 was not affected by the high production of pediocin by UVA1 during co‐culture (up to 12·8 μg ml −1 ). Furthermore, a real‐time PCR assay was developed and allowed gene‐expression analysis of the pediocin‐gene pedA . Conclusions: The co‐culture of RBL67 and UVA1 showed high stability, cell yields and bacteriocin production during batch cultures and has potential for use as a probiotic mixture with antibacterial properties. In addition, a gene‐expression real‐time PCR assay was successfully developed, used for the relative quantification of the pediocin transcript pedA and demonstrated to be a valuable complementary tool to activity assay. Significance and Impact of the Study: This is the first study reporting of a stable mixed culture of two bacteriocin‐producing strains of human origin.