Inhibition of Bacillus cereus in milk fermented with kefir grains

The effects of kefir-fermented milk were tested against a toxigenic strain of Bacillus cereus. The incubation of milk with B. cereus spores plus 5% kefir grains prevented spore germination and growth of vegetative forms. In contrast, when 1% kefir grains was used, no effects were observed. The prese...

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Detalles Bibliográficos
Autores: Kakisu, Emiliano J., Abraham, Analía Graciela, Pérez, Pablo Fernando, De Antoni, Graciela Liliana
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/143595
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/143595
Access Level:acceso abierto
Palabra clave:Química
Kefir-fermented milk
Bacillus cereus
Descripción
Sumario:The effects of kefir-fermented milk were tested against a toxigenic strain of Bacillus cereus. The incubation of milk with B. cereus spores plus 5% kefir grains prevented spore germination and growth of vegetative forms. In contrast, when 1% kefir grains was used, no effects were observed. The presence of metabolically active kefir grains diminished titers of nonhemolytic enterotoxin A, as assessed by enzyme-linked immunosorbent assay. During fermentation, kefir microorganisms produce extra-cellular metabolites such as organic acids, which could play a role in the inhibition of spore germination and growth of B. cereus, although the effect of other factors cannot be ruled out. Results of the present study show that kefir-fermented milk is able to antagonize key mechanisms involved in the growth of B. cereus as well as interfere with the biological activity of this microorganism.