Original scientific paper
Competitive advantage of bacteriocinogenic strains within lactic acid bacteria consortium of raw milk cheese
Aljoša Trmčić
Tanja Obermajer
Andreja Čanžek Majhenič
Bojana Bogovič Matijašić
Irena Rogelj
orcid.org/0000-0002-2056-4888
; Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Groblje 3, SI-1230 Domžale, Slovenia
Abstract
The presence of gene determinants for different bacteriocins has been already demonstrated in traditional Slovenian types of raw milk cheeses ‘Tolminc’ and ‘Kraški’. These genes were present also in the cultivable microbiota. In this research the aim was to establish how the presence of gene determinants for bacteriocins in microbial consortia is reflected in its antimicrobial activity. In addition, one of the goals was to determine whether the strains that carry gene determinants for bacteriocins have any competitive growth advantage in microbial population. Microbial consortium of ‘Tolminc’ cheese was propagated in milk and examined at the end of propagation its antimicrobial activity and the presence of gene determinants for bacteriocins. Comparison of the results obtained before and after propagation leaded to the conclusion that most of the strains possessing gene determinants for bacteriocins were unable to persist during propagation. The strains which did persist during propagation carried gene determinants for enterocins P, L50B and cytolysin. Antimicrobial activity of consortium before and after propagation was not substantially different and cannot be attributed to any of detected bacteriocins.
Keywords
traditional cheese; bacteriocin genes; bacteriocins; antimicrobial activity; competition
Hrčak ID:
65201
URI
Publication date:
15.3.2011.
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