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On Lactococcus lactis UL719 competitivity and nisin (Nisaplin(®)) capacity to inhibit Clostridium difficile in a model of human colon.

Le Lay C, Fernandez B, Hammami R, Ouellette M, Fliss I - Front Microbiol (2015)

Bottom Line: Bacterial populations was enumerated by qPCR coupled to PMA treatment.L. lactis UL719 was able to survive and proliferate under simulated human colon, did not alter microbiota composition, but failed to inhibit C. difficile.While a single dose of 19 μmol/L (5× the MIC) was not sufficient to inhibit C. difficile, nisin at 76 μmol/L (20×the MIC) was effective at killing the pathogen.

View Article: PubMed Central - PubMed

Affiliation: STELA Dairy Research Center, Nutrition and Functional Foods Institute, Université Laval, Québec QC, Canada ; Centre de Recherche en Infectiologie de l'Université Laval, Axe Maladies Infectieuses et Immunitaires, Centre de Recherche du CHU de Québec, Québec QC, Canada ; Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec QC, Canada.

ABSTRACT
Clostridium difficile is the most frequently identified enteric pathogen in patients with nosocomially acquired, antibiotic-associated diarrhea and pseudomembranous colitis. Although metronidazole and vancomycin were effective, an increasing number of treatment failures and recurrence of C. difficile infection are being reported. Use of probiotics, particularly metabolically active lactic acid bacteria, was recently proposed as an alternative for the medical community. The aim of this study was to assess a probiotic candidate, nisin Z-producer Lactococcus lactis UL719, competitivity and nisin (Nisaplin(®)) capacity to inhibit C. difficile in a model of human colon. Bacterial populations was enumerated by qPCR coupled to PMA treatment. L. lactis UL719 was able to survive and proliferate under simulated human colon, did not alter microbiota composition, but failed to inhibit C. difficile. While a single dose of 19 μmol/L (5× the MIC) was not sufficient to inhibit C. difficile, nisin at 76 μmol/L (20×the MIC) was effective at killing the pathogen. Nisin (at 76 μmol/L) caused some temporary changes in the microbiota with Gram-positive bacteria being the mostly affected. These results highlight the capacity of L. lactis UL719 to survive under simulated human colon and the efficacy of nisin as an alternative in the treatment of C. difficile infections.

No MeSH data available.


Related in: MedlinePlus

Time schedule of continuous intestinal fermentation during the different treatment periods. BC, bead colonization. Lactococcus lactis UL719 was added at final concentration of 109 CFU/mL in the reactor. Clostridium difficile ATCC43255 was added at a final concentration of 5 × 106 CFU/mL.
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Figure 1: Time schedule of continuous intestinal fermentation during the different treatment periods. BC, bead colonization. Lactococcus lactis UL719 was added at final concentration of 109 CFU/mL in the reactor. Clostridium difficile ATCC43255 was added at a final concentration of 5 × 106 CFU/mL.

Mentions: The fermentation process was carried out for a total of 82 days and microbiota was stabilized 2 weeks before challenging tests. First, a cell suspension of L. lactis UL719 (at final concentration 109 CFU/mL in the reactor) was added twice to the reactor (day 17 and 22) (Figure 1). Then, nisin A (Nisaplin®, Danisco, Copenhagen, Denmark) was added to the reactor at 5× (at day 27 and 32) and 20× (at day 37 and 42) the MIC (3.8 μmol/L vs. C. difficile) to measure the impact of high doses of nisin on the intestinal flora. Next, challenges with C. difficile ATCC43255 (at a final concentration of 5 × 106 CFU/mL in the reactor) in absence (day 47 and 52) or in presence of L. lactis (added at a final concentration of 109 CFU/mL in the reactor; day 57 and 62) or in presence of different concentrations of nisin A [5× (day 67 and 72) or 20× (day 77 and 82) the MIC] were performed. Samples were collected for bacterial enumeration by qPCR. After each addition, samples were hourly taken during first 4 and at 8 h.


On Lactococcus lactis UL719 competitivity and nisin (Nisaplin(®)) capacity to inhibit Clostridium difficile in a model of human colon.

Le Lay C, Fernandez B, Hammami R, Ouellette M, Fliss I - Front Microbiol (2015)

Time schedule of continuous intestinal fermentation during the different treatment periods. BC, bead colonization. Lactococcus lactis UL719 was added at final concentration of 109 CFU/mL in the reactor. Clostridium difficile ATCC43255 was added at a final concentration of 5 × 106 CFU/mL.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4585240&req=5

Figure 1: Time schedule of continuous intestinal fermentation during the different treatment periods. BC, bead colonization. Lactococcus lactis UL719 was added at final concentration of 109 CFU/mL in the reactor. Clostridium difficile ATCC43255 was added at a final concentration of 5 × 106 CFU/mL.
Mentions: The fermentation process was carried out for a total of 82 days and microbiota was stabilized 2 weeks before challenging tests. First, a cell suspension of L. lactis UL719 (at final concentration 109 CFU/mL in the reactor) was added twice to the reactor (day 17 and 22) (Figure 1). Then, nisin A (Nisaplin®, Danisco, Copenhagen, Denmark) was added to the reactor at 5× (at day 27 and 32) and 20× (at day 37 and 42) the MIC (3.8 μmol/L vs. C. difficile) to measure the impact of high doses of nisin on the intestinal flora. Next, challenges with C. difficile ATCC43255 (at a final concentration of 5 × 106 CFU/mL in the reactor) in absence (day 47 and 52) or in presence of L. lactis (added at a final concentration of 109 CFU/mL in the reactor; day 57 and 62) or in presence of different concentrations of nisin A [5× (day 67 and 72) or 20× (day 77 and 82) the MIC] were performed. Samples were collected for bacterial enumeration by qPCR. After each addition, samples were hourly taken during first 4 and at 8 h.

Bottom Line: Bacterial populations was enumerated by qPCR coupled to PMA treatment.L. lactis UL719 was able to survive and proliferate under simulated human colon, did not alter microbiota composition, but failed to inhibit C. difficile.While a single dose of 19 μmol/L (5× the MIC) was not sufficient to inhibit C. difficile, nisin at 76 μmol/L (20×the MIC) was effective at killing the pathogen.

View Article: PubMed Central - PubMed

Affiliation: STELA Dairy Research Center, Nutrition and Functional Foods Institute, Université Laval, Québec QC, Canada ; Centre de Recherche en Infectiologie de l'Université Laval, Axe Maladies Infectieuses et Immunitaires, Centre de Recherche du CHU de Québec, Québec QC, Canada ; Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec QC, Canada.

ABSTRACT
Clostridium difficile is the most frequently identified enteric pathogen in patients with nosocomially acquired, antibiotic-associated diarrhea and pseudomembranous colitis. Although metronidazole and vancomycin were effective, an increasing number of treatment failures and recurrence of C. difficile infection are being reported. Use of probiotics, particularly metabolically active lactic acid bacteria, was recently proposed as an alternative for the medical community. The aim of this study was to assess a probiotic candidate, nisin Z-producer Lactococcus lactis UL719, competitivity and nisin (Nisaplin(®)) capacity to inhibit C. difficile in a model of human colon. Bacterial populations was enumerated by qPCR coupled to PMA treatment. L. lactis UL719 was able to survive and proliferate under simulated human colon, did not alter microbiota composition, but failed to inhibit C. difficile. While a single dose of 19 μmol/L (5× the MIC) was not sufficient to inhibit C. difficile, nisin at 76 μmol/L (20×the MIC) was effective at killing the pathogen. Nisin (at 76 μmol/L) caused some temporary changes in the microbiota with Gram-positive bacteria being the mostly affected. These results highlight the capacity of L. lactis UL719 to survive under simulated human colon and the efficacy of nisin as an alternative in the treatment of C. difficile infections.

No MeSH data available.


Related in: MedlinePlus