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Comparative Evaluation of Antibacterial Activity of Probiotics SK12 and SM18: An In Vitro Study
Srihari Nirguna Chandrasekhar1, Shanthala B Mallikarjun1, Henna P Salim1
1Department of Pediatric and Preventive Dentistry, Coorg Institute of Dental Sciences, Virajpet, Karnataka, India.
Aim:
To assess the antimicrobial activity of probiotics SK12 and SM18 on Streptococcus mutans and also to compare the antimicrobial activity of SK12 and SM18.
Materials And Methods:
Synthetic strains of Streptococcus mutans were used to study the antimicrobial activity of probiotics SK12 and SM18 using various tests such as disk diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). In disk diffusion, the zone of inhibition was measured to assess the antimicrobial activity. Chlorhexidine was used as a control for this test. The MIC and MBC were assessed at different dilutions of the probiotic sample (100 mg/mL, 50 mg/mL, 25 mg/mL, 12.5 mg/mL, 6.25 mg/mL, 3.12 mg/mL, 1.6 mg/mL, 0.8 mg/mL, 0.4 mg/mL, and 0.2 mg/mL).
Result:
SM18 demonstrated 20 mm of zone of inhibition, whereas SK12 demonstrated 15 mm showing a less antibacterial activity in comparison to SM18. SM18 was found to be bactericidal and effective at a minimum concentration of 0.8 mg/mL, whereas SK12 was bactericidal and effective at a minimum concentration of 1.6 mg/mL.
Conclusion:
Probiotics demonstrate antibacterial activity against cariogenic microflora. SM is 18 having a better antibacterial activity at lower concentrations than SK12 in reducing cariogenic microorganisms. Clinical significance: BLIS K12 and M18 both demonstrated an antibacterial effect on Streptococcus mutans, wherein the use of probiotic in caries prevention is found to be limited. Hence, it is suggestive to reap the bacterial effects of BLIS K12 and M18 in caries prevention.
How To Cite This Article:
Chandrasekhar SN, Mallikarjun SB, Salim HP. Comparative Evaluation of Antibacterial Activity of Probiotics SK12 and SM18: An In Vitro Study. Int J Clin Pediatr Dent 2020;13(6):611-616.
Insights
Probiotic strain SM18 shows superior antimicrobial activity against Streptococcus mutans compared to SK12. SM18 is effective at lower concentrations, highlighting its potential in managing cariogenic bacteria.
Area of Science:
- Oral microbiology
- Probiotic research
- Antimicrobial susceptibility testing
Background:
- Streptococcus mutans is a primary etiological agent of dental caries.
- Probiotics are being investigated for their potential to modulate oral microbiota and prevent caries.
- This study evaluates the in vitro antimicrobial efficacy of two probiotic strains, SK12 and SM18, against S. mutans.
Discussion:
- Both SK12 and SM18 probiotics exhibited antimicrobial activity against Streptococcus mutans.
- SM18 demonstrated a larger zone of inhibition (20 mm) compared to SK12 (15 mm).
- SM18 was bactericidal at a minimum concentration of 0.8 mg/mL, while SK12 required 1.6 mg/mL.
Key Insights:
- Probiotic SM18 possesses stronger antibacterial properties against S. mutans than probiotic SK12.
- Lower concentrations of SM18 are effective in inhibiting and killing S. mutans.
- The findings support the targeted application of specific probiotic strains for caries prevention.
Outlook:
- Further in vivo studies are warranted to confirm the clinical efficacy of SM18 in caries prevention.
- Investigating the mechanisms of action of SM18 against S. mutans could provide deeper insights.
- Optimizing probiotic formulations and delivery methods may enhance their therapeutic potential in oral health.
