Title : Anti-streptococcus mutans, anti-adherence and anti-acidogenic activity of uvaria chamae P beauv
Abstract:
Dental caries is the most prevalent oral infection resulting from accumulation and multiplication of bacteria in the oral cavity. It is caused by demineralisation of the tooth due to the acids produced by Streptococcus mutans from fermentable carbohydrates. Pathogenic characteristics of S. mutans include biofilm formation, production of extracellular polysaccharides, acidogenicity and aciduricity. Dental caries can be prevented by controlling bacterial biofilm also called plaque with antimicrobial oral hygiene products. Medicinal plants have shown antimicrobial activity against these oral bacteria.
Uvaria chamae have been used to treat various infections. It has proven antiparasitic, antiplasmodial, antidiabetic, antimicrobial, and antioxidant properties. Although the anti-S. mutans activity of this plant has been reported, its effect on the virulence properties has not been studied. Therefore, this study aimed to investigate the antimicrobial activity of U. chamae roots extracts on S. mutans virulence factors. Methods: The plant extracts were prepared using methanol, dichloromethane, hexane, ethanol, and methanol: water. Minimum bactericidal/MIC concentrations (MBC) were obtained against S. mutans using double dilution technique. Subsequently, best effective solvent was selected for antivirulence study. The MIC, ½ and ¼ MIC concentrations of the dichloromethane extract were evaluated for their effect on biofilm formation, acid, and extracellular polysaccharides production by S. mutans.
The effect of the plant extract on the expression of virulence genes (gtfB, gtfC, spaP, IDH, atpD, vicR, brpA, and gbpB) was also investigated using RT-qPCR. The results were analysed using the one-way ANOVA and Wilcoxon Rank Sum Test. Results: The mean MIC of U. chamae roots extracts against S. mutans ranged between 0.02 and 1.25 mg/ml and the MBC ranged between 0.04 and 1.25 mg/ml. The dichloromethane plant extract showed the best antibacterial activity against all the five cariogenic S. mutans strains with an average MIC and MBC of 0.02 and 0.04 mg/ml respectively and was used in the subsequent experiments such as the biofilm, acid, EPS, and RT-qPCR assay. At 6 hours, exposure to 0.005, 0.01, and 0.02 mg/ml of the plant extract reduced biofilm formation by 39.70, 59.17, and 76.82 %. At 24 hours, the percentage reduction of the biofilm counts significantly improved up to 91 %. Not much difference in the test results was observed between 24 and 30 hours.
The plant extract also significantly inhibited acid production (p < 0.01). The roots extract did not inhibit the production of soluble and insoluble extracellular polysaccharides. Furthermore, a significant decline in the transcription of virulence genes (gbpB, vicR, brpA, spaP, gtfB, gtfC, atpD, and IDH) was observed in the presence of the plant extract. Conclusion: The Uvaria chamae extracts showed the best antibacterial activity. At subinhibitory concentrations, this plant extract significantly inhibited biofilm formation, acid production, and virulent gene expression by S. mutans. Therefore, this suggests that U. chamae has the potential to control and prevent dental caries.
Audience Take Away:
- They should target virulence rather killing microbes
- She enjoys the application of logical thinking as a tool for exploring and satisfying curiosity about microbes and the world.
- Research is set to explore and make mysterious discoveries to improve the quality of life.
- It provide a practical solution to the world of microbes
- Render pathogens avirulent and less infectious.
