Izvorni znanstveni članak
In-situ inhibition of Staphylococcus aureus by lactic acid bacteria consortia from two traditional Slovenian raw milk cheeses
Aljoša Trmčić
; Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Groblje 3, Domžale, Slovenia
Tanja Obermajer
Andreja Čanžek Majhenič
Irena Rogelj
Bojana Bogovič Matijašić
Sažetak
Bacteriocin(s) producing lactic acid bacteria naturally present in traditional cheeses represent an inexhaustive pool of microbes with safeguarding potential. Some bacteriocins produced by cheese lactic acid bacteria were already described as successful anti-staphylococcal agents. The presence of genes for bacteriocins with potential anti-staphylococcal activity was also demonstrated in two Slovenian traditional raw milk cheeses, “Tolminc” and “Kraški ovčji sir”. Same bacteriocin genes were also detected in viable lactic acid bacteria consortia’s isolated from “bacteriocin positive cheeses” on Rogosa, M17 and CATC agar media. The aim of the research was to elucidate whether or not this particular cheese consortia, in which bacteriocin genes were detected, actually exhibit anti-staphylococcal activity in milk and/or cheese. For this purpose different cheese consortia were selected in relation to versatility of detected bacteriocin genes and used to perform challenge tests against Staphylococcus aureus in milk and cheese. In milk following the time/temperature regime of traditional cheese production all cheese consortia effectively inhibited growth of Staphylococcus aureus in the range of app. 2 to 3 log. In cheese the inhibition of staphylococci was less pronounced but still evident since inhibition of app. 1.5 log was detected. Sole inhibition by lactic acid production was ruled out while
linking inhibition directly to bacteriocin production would take some additional work.
Ključne riječi
traditional cheeses; safety; LAB consortia; anti-staphylococcal activity
Hrčak ID:
59015
URI
Datum izdavanja:
29.9.2010.
Posjeta: 2.475 *