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Streptococcus strain C17T as a potential probiotic candidate to modulate oral health
Wen Xiao Zhang1, Chun Ling Xiao1, Shu Yin Li1
1Key Lab of Environmental Pollution and Microecology of Liaoning Province, Shenyang Medical College, Shenyang, Liao Ning, People's Republic of China.
Insights
A novel Streptococcus strain, C17T, shows promising probiotic potential for oral health. It survives harsh conditions and inhibits pathogenic bacteria, offering a new avenue for oral disease modulation.
Area of Science:
- Microbiology
- Probiotics
- Oral Health
Background:
- Probiotics play a role in modulating oral diseases within the microbiome.
- The oropharynx is a key site for microbial interactions relevant to oral health.
Purpose of the Study:
- To investigate the probiotic potential of a newly isolated Streptococcus strain C17T.
- To evaluate its efficacy as an oropharyngeal probiotic using an in vitro model.
Main Methods:
- Isolation of Streptococcus strain C17T from a healthy child's oropharynx.
- In vitro analysis of strain C17T using human bronchial epithelial cells (16-HBE) as an oropharyngeal mucosal model.
- Assessment of tolerance to pH, bile, lysozyme, and hydrogen peroxide; evaluation of antimicrobial and anti-adhesive properties against pathogenic bacteria.
Main Results:
- Strain C17T demonstrated tolerance to pH 4-5, moderate bile concentrations (0.5-1%), lysozyme (200 μg/ml), and hydrogen peroxide (0.8 mM).
- The strain exhibited inhibitory activity against common pathogenic bacteria and a significant anti-adhesive effect against Staphylococcus aureus.
- C17T showed no cytotoxicity to 16-HBE cells and adhered to them, indicating good mucosal interaction.
Conclusions:
- Streptococcus strain C17T possesses significant probiotic properties suitable for oropharyngeal application.
- This strain demonstrates potential for modulating oral diseases through its resilience and inhibitory actions against pathogens.
Abstract:
In the microbiome, probiotics modulate oral diseases. In this study, Streptococcus strain C17T was isolated from the oropharynx of a 5-year-old healthy child, and its potential probiotic properties were analysed using human bronchial epithelial cells (16-HBE) used as an in vitro oropharyngeal mucosal model. The results demonstrated that the C17T strain showed tolerance to moderate pH ranges of 4-5 and 0·5-1% bile. However, it was more tolerant to 0·5% bile than 1% bile. It also demonstrated an ability to accommodate maladaptive oropharyngeal conditions (i.e. tolerating lysozyme at 200 μg ml-1 ). It was also resistant to hydrogen peroxide at 0·8 mM. In addition, we found out that the strain possesses inhibitory activities against various common pathogenic bacteria. Furthermore, C17T was not cytotoxic to 16-HBE cells at different multiplicities of infection. Scanning electron microscopy disclosed that C17T adhesion to 16-HBE cells. Competition, exclusion and displacement assays showed that it had good anti-adhesive effect against S. aureus. The present study revealed that Streptococcus strain C17T is a potentially efficacious oropharyngeal probiotic.
