Coaggregation between probiotic bacteria and caries-associated strains: an in vitro study.

Area of Science:

• Microbiology
• Oral Health
• Probiotics

Background:

• Mutans streptococci are key etiological agents in dental caries.
• Probiotic bacteria, particularly lactobacilli, are explored for their potential to modulate oral microbiota and prevent caries.
• Coaggregation, the adherence of different bacterial species, is a mechanism that may influence microbial ecology in the oral cavity.

Purpose of the Study:

• To investigate the in vitro coaggregation capabilities of specific probiotic lactobacilli strains with caries-associated mutans streptococci.
• To determine if coaggregation is strain-specific and time-dependent.

Main Methods:

• Six Lactobacillus strains were cultured and four human Streptococcus strains (including S. mutans and S. sobrinus) were grown.
• Coaggregation was quantified using spectrophotometry over 24 hours.
• Bacterial identity was confirmed using the API 50 CH system.

Main Results:

• All tested probiotic strains demonstrated coaggregation with oral pathogens, with significant strain and time-dependent variations.
• Streptococcus mutans GS-5 showed the highest coaggregation with all tested probiotic strains.
• Lactobacillus acidophilus exhibited the highest coaggregation propensity, while Lactobacillus rhamnosus LB21 showed the least.

Conclusions:

• Lactobacilli-derived probiotic bacteria exhibit diverse in vitro coaggregation abilities with oral streptococci.
• Aggregation assays can serve as a valuable tool for screening probiotic candidates with potential anti-caries properties.