Probiotic potential of Lactobacillus delbrueckii strains and their phage resistant mutants

Stability of selected lactobacilli in the conditions simulating those in the gastrointestinal tract

“…These results show that milk exerted a strong protective effect against the stress conditions of the digestive tract. The protective effect of milk on the survival of the L. delbrueckii strains in the environment simulating gastric juice was also confirmed by Guglielmotti et al (2007). After the addition of re-skimmed milk (20% (v/v)) to the solution simulating gastric juice and 90 min incubation, no significant decrease was observed in the number of viable cells.…”

“…The method for the testing of tolerance towards the conditions simulating those in the gastrointestinal tract was adapted according to Guglielmotti et al (2007) and Botes et al (2008). An overnight culture in MRS broth (pH 5.6, at 37°C in CO 2 atmosphere (4% v/v)) were centrifuged (8690 g, 12 min, 5°C), washed in buffer, centrifuged once again, and the isolated cells were transferred into a solution simulating the stomach conditions (50 ml HCl, pH 2, 0.5% w/v NaCl, 0.3% w/v pepsin; Sigma-Aldrich, St. Louis, USA).…”

Identification and characterization of Bacillus subtilis from grass carp (Ctenopharynodon idellus) for use as probiotic additives in aquatic feed

“…Meanwhile, tolerances to gastric (low pH) and intestinal (high bile concentration) conditions are the foundation for probiotics to survive and then colonize in the gut to produce beneficial traits [27,50]. In this study, persistence of the B. subtilis spores was assessed at high temperature, low pH, and high concentration of bile.…”

“…Resistances to gastric (low pH) and intestinal (high bile concentration) conditions are tested in vitro frequently to evaluate probiotic candidates [27]. When incubated in simulated gastric juice at low pH for 2 h, no significant differences were observed in the loss of viabilities of the spores, although the viabilities were reduced as pH decreased (Table 6).…”

Delivery of Probiotic Microorganisms into Gastrointestinal Tract by Food Products

“…The resistance to lysozyme at 25-35 mg L -1 was recommended as a criterion for the selection of a lactic acid bacterial strain suitable for use in milk industry (Guglielmonti et al, 2007). The resistance to lysozyme at 25-35 mg L -1 was recommended as a criterion for the selection of a lactic acid bacterial strain suitable for use in milk industry (Guglielmonti et al, 2007). According to findings, the tolerance of probiotics to lysozyme is strain-dependent (Rada et al, 2010).…”