Growth inhibition of glucose-grown cariogenic and other streptococci by saccharin in vitro.

Recently, the in vitro physiological effects were studied of several sucrose substitutes and artificial sweeteners on growth pattern and acid production of 7 glucose-grown Streptococcus mutans strains 1, representing the 5 serological groups after Bratthall 2. It was found that out of several sweeteners saccharin is the only compound which, depending on its concentration (0.02 to 20.00 m g/m l), signif­ icantly reduced or even inhibited the cellular growth of all tested S. mutans strains. Furthermore, in the presence of higher saccharin concentrations the final pH of the inoculated medium after 24 hours of incubation increased up to 1.8 units, which is far above the critical pH of 5.50 in dental plaque, necessary for determineralization of the teeth and caries formation 3’ 4. We now extended the aforementioned in vitro saccharin study to cover besides a greater variety of S. mutans strains, belonging to the 8 serotypes a to g and SL-1 after B ratthall2 and Perch et al. 5, also other streptococci typical of viridans, enterococcus, pyogenic and lactic groups. Moreover, to acquire information on the inhibitory effect of sac­ charin on growth of streptococci in general, and to obtain proof that this growth inhibition is not limited to S. mutans but that also other oral Strepto­ coccus species are affected by this compound.