Probiotic potential of Lactobacillus delbrueckii strains and their phage resistant mutants

DANIELA M. GUGLIELMOTTI, MARIANGELES BRIGGILER MARCÓ, MARINA GOLOWCZYC, JORGE A. REINHEIMER, ANDREA DEL L. QUIBERONI.

INTERNATIONAL DAIRY JOURNAL

Año: 2007 p. 916 - 925

0958-6946

Three commercial phage sensitive strains of Lactobacillus delbrueckii and spontaneous phage resistant mutants isolated from them were studied by focusing on their biological and probiotic features. After incubation in a simulated gastric solution (pH 2.0), viable cell counts decreased moderately, but a protective effect on strains was observed when milk was added. A limited resistance to bile was observed, while most of the strains tolerated lysozyme, and grew in the presence of bile salts and fermented prebiotics. Some strainsshowed high hydrophobicity values and b-galactosidase activity. The strong antibacterial activity displayed toward pathogens was due to the production of lactic acid. Sensitive strains and their phage resistant variants were able to adhere to Caco-2/TC-7 monolayers and significantly inhibited the invasion of Salmonella enterica serovar Enteritidis into Caco-2/TC-7 cells. All strains tested showed potential probiotic features, suggesting a potential probiotic role of L. delbrueckii.