IADR Abstract Archives
Does the bacteriocin nisin affect Streptococcus mutans biofilm?
Objectives: Probiotics are defined as live microorganisms that are believed to provide health benefits when consumed. Recently, probiotics bacteria have been proposed also to dentistry. In oral cavity, probiotics bacteria can adhere to dental tissues as part of the biofilm or plaque and compete with dental pathogens producing organic acids and bacteriocins, hence, preventing dental caries, periodontal diseases and improving oral health. The objective of the present study is to determine the effect of nisin on dental biofilm.
Methods: The effect of the bacteriocin nisin produced by Lactococcus Lactis was tested on Streptococcus mutans in biofilm conditions. S. mutans were grown overnight in 37OC in the presence of different concentrations of nisin 5-40 µg/ml (BHI supplemented with 40% sucrose). The effect of nisin on S. mutans biofilm was checked by turbidity OD (λ=595nm). The biofilm biomass was quantified by crystal violet staining and MTT assay was applied for assessing cell metabolic activity. Confocal laser scanning was used to check depth selectivity of S. mutans biofilm.
Results: The addition of nisin showed significant effect on S. mutans growth in the highest tested concentration in the biofilm. Importantly, the HCL 0.02N used to prepare nisin, wasn’t able to inhibit S. mutans growth. Lower tested concentrations between 5-15 µg/ml did not have a significant effect on the biofilm.
At concentrations of 20-40 µg/ml, the bio-mass measured by crystal violet staining showed significant decrease. Confocal laser scanning microscopy showed also a significant decrease in biofilm in the presence of nisin, specifically decrease in live bacteria in comparison to control group, especially at 40 µl nisin concentration. Lower cell metabolic activity of S. mutans, measured by the MTT, was verified at 40 µg/ml nisin.
Conclusions: Our results suggest that nisin at 40 μg/ml may be a potential anti-biofilm agent against S mutans.
Methods: The effect of the bacteriocin nisin produced by Lactococcus Lactis was tested on Streptococcus mutans in biofilm conditions. S. mutans were grown overnight in 37OC in the presence of different concentrations of nisin 5-40 µg/ml (BHI supplemented with 40% sucrose). The effect of nisin on S. mutans biofilm was checked by turbidity OD (λ=595nm). The biofilm biomass was quantified by crystal violet staining and MTT assay was applied for assessing cell metabolic activity. Confocal laser scanning was used to check depth selectivity of S. mutans biofilm.
Results: The addition of nisin showed significant effect on S. mutans growth in the highest tested concentration in the biofilm. Importantly, the HCL 0.02N used to prepare nisin, wasn’t able to inhibit S. mutans growth. Lower tested concentrations between 5-15 µg/ml did not have a significant effect on the biofilm.
At concentrations of 20-40 µg/ml, the bio-mass measured by crystal violet staining showed significant decrease. Confocal laser scanning microscopy showed also a significant decrease in biofilm in the presence of nisin, specifically decrease in live bacteria in comparison to control group, especially at 40 µl nisin concentration. Lower cell metabolic activity of S. mutans, measured by the MTT, was verified at 40 µg/ml nisin.
Conclusions: Our results suggest that nisin at 40 μg/ml may be a potential anti-biofilm agent against S mutans.