To compare the effects of five probiotic lactobacilli strains on the growth and biofilm formation ofStreptococcus mutans(MS).MATERIALS AND METHODS:
Five probiotic lactobacilli bacteria (LB),Lactobacillus caseiShirota,Lactobacillus caseiLC01,Lactobacillus plantarumST-III,Lactobacillus paracaseiLpc-37, andLactobacillus rhamnosusHN001, were used as test strains effecting on the Streptococci strainS. mutansUA159 in this study. The effect of LB strains and their supernatants on the viability of the MS was evaluated. Then, the effect of LB strains on the growth of MS biofilm formation was observed by fluorescence microscope.RESULTS:
All of the LB strains inhibited the growth of MS at concentrations of 1 × 108 and 3 × 108 CFU ml−1 (P< 0.05). Untreated (without pH adjustment and ultrafiltration) LB supernatants from all of the LB strains inhibited the growth of MS (P< 0.05) as well. After pH adjustment and ultrafiltration (treated), only supernatants fromL. caseiShirota andL. rhamnosusHN001 inhibited the growth of MS (P< 0.05). MS biofilm formation was also inhibited by all untreated supernatants and by the treated supernatants ofL. caseiShirota andL. rhamnosusHN001 (P< 0.05).CONCLUSION:
All five probiotic lactobacilli strains inhibited the growth and biofilm formation of MS, likely through the production of an acid environment, bacteriocin-like poly peptides, or both, and the effects on MS were dependent on the LB strains used.