e Brevibacterium aurantiacum, C casei, C variabile, Mc gubbee

e. Brevibacterium aurantiacum, C. casei, C. variabile, Mc. gubbeenense and St. MK-8776 manufacturer saprophyticus, were shown to use lactate and casaminoacids for growth [42]. In contrast, Listeria sp. can only use a limited range of carbon sources for growth, including glucose, glycerol, fructose and mannose, while no growth occurs on lactate or casaminoacids [43–46]. Premaratne et al. [44] showed that Listeria monocytogenes may utilize alternative carbon sources, such as N-acetylglucosamine and N-acetylmuramic acid, which are major components of bacterial and

fungal cell walls [44, 47]. In addition, the yeast cell wall contains a mannan glycopeptide with mannose [48], a sugar metabolized by Listeria sp. Listeria growth on smear cheese can therefore be limited by a low availability S3I-201 price of carbon source and stimulated by components of smear microorganisms. Marine LAB ferment glucose into lactate and assimilate mannose [37, 38]. Ishikawa et al. [38] reported that Al. kapii can utilize a fairly limited range of carbon sources. In the present study, M. psychrotolerans and/or Al. kapii established early on cheeses treated by complex consortia, i.e. see more between day 14 and day 20. We believe competition for nutrients

between marine LAB and Listeria sp. may be involved in Listeria inhibition in the smear since the development of M. psychrotolerans and Al. kapii occurred simultaneously with the decrease of Listeria counts for both cheeses treated with consortium F (first trial and repetition) and for one cheese treated with consortium M (repetition). In addition, Listeria growth on control cheese stopped when M. psychrotolerans and Al. kapii were first detected in the smear, i.e. on day 37. Hain et al. [49] reported a microarray experiment conducted with the antilisterial complex smear consortium described by Maoz et al. [9]. Genes involved in energy supply were mostly up-regulated after 4 hours of contact between Listeria monocytogenes and the consortium, suggesting that Listeria had entered a state of starvation. While Maoz et al. [9] detected M. psychrotolerans in the aforesaid smear consortium by

cultivation methods, they may have overlooked the presence of Al. kapii or related selleck kinase inhibitor species. Conclusions This work reports the first study of population dynamics of antilisterial cheese surface consortia. Dynamics of two consortia obtained from industrial productions revealed highly similar, with the sequential development of 9 common species, whereas development of both consortia inhibited Listeria growth over the whole ripening period. Next to common cheese surface bacteria, the two consortia contained marine lactic acid bacteria (LAB) that developed early in ripening, shortly after the growth of staphylococci and concomitant with a decrease in Listeria cell counts. Competition for nutrients between marine LAB and Listeria sp. could be involved in the observed inhibition.

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