IADR Abstract Archives
Growth and Safety of Lactobacillus GG Under Different Sugar Conditions
Objectives: Administration of probiotic strains has emerged as an encouraging alternative treatment in prevention of dental caries. This in vitro study aimed to assess the ability of Lactobacillus rhamnosus GG (L.GG) to establish in oral biofilms; the pH changes of the spent media in its presence in the biofilms; and the role of glucose, fructose, lactose, sorbitol, and sucrose as a sole carbohydrate source in biofilm models.
Methods: 64.5h multi-species oral biofilms with L.GG were grown with one of the carbohydrates under anaerobic conditions at 37°C. The viable cells of L.GG were examined at 64.5h, and the pH values of the spent media were measured at 16.5h, 40.5h and 64.5h. In addition, fermentation profiles of L.GG in biofilm medium with the carbohydrates were also assessed. For comparison, biofilm experiment without L.GG was also made.
Results: Our results showed that fermentation profiles of L.GG in biofilm medium were similar to its growth in MRS (no clear growth of L.GG was found in groups of lactose and sucrose). However, the best growth of L.GG in multi-species biofilms appeared when glucose and sucrose were used, the lowest pH values of spent media were detected when lactose was used. When L.GG was incorporated in the biofilms, no significant changes of pH values were observed under any of the carbohydrates used. The results of biofilm experiment without L.GG were comparable to the L.GG series.
Conclusions: In conclusion, LGG as a member of multi-species in vitro oral biofilms grew well in the presence of each of the tested five carbohydrates. The observed pH reductions in the presence of glucose and sucrose are within the range of pH values which do not expose hard dental tissues at higher risk of dental caries. Also lactose caused the most pH decrease observed in the current oral biofilm model system.
Methods: 64.5h multi-species oral biofilms with L.GG were grown with one of the carbohydrates under anaerobic conditions at 37°C. The viable cells of L.GG were examined at 64.5h, and the pH values of the spent media were measured at 16.5h, 40.5h and 64.5h. In addition, fermentation profiles of L.GG in biofilm medium with the carbohydrates were also assessed. For comparison, biofilm experiment without L.GG was also made.
Results: Our results showed that fermentation profiles of L.GG in biofilm medium were similar to its growth in MRS (no clear growth of L.GG was found in groups of lactose and sucrose). However, the best growth of L.GG in multi-species biofilms appeared when glucose and sucrose were used, the lowest pH values of spent media were detected when lactose was used. When L.GG was incorporated in the biofilms, no significant changes of pH values were observed under any of the carbohydrates used. The results of biofilm experiment without L.GG were comparable to the L.GG series.
Conclusions: In conclusion, LGG as a member of multi-species in vitro oral biofilms grew well in the presence of each of the tested five carbohydrates. The observed pH reductions in the presence of glucose and sucrose are within the range of pH values which do not expose hard dental tissues at higher risk of dental caries. Also lactose caused the most pH decrease observed in the current oral biofilm model system.