Efficacy of E. officinalis on the cariogenic properties of Streptococcus mutans: a novel and alternative approach to suppress quorum-sensing mechanism

PLoS One. 2012;7(7):e40319. doi: 10.1371/journal.pone.0040319. Epub 2012 Jul 5.

Abstract

The present study was focused on evaluating the potential of Emblica officinalis against cariogenic properties of Streptococcus mutans, a causative microorganism for caries. The effect of crude extract and ethanolic fraction from Emblica officinalis fruit was analysed against S. mutans. The sub-MIC concentrations of crude and ethanolic fraction of E. officinalis were evaluated for its cariogenic properties such as acid production, biofilm formation, cell-surface hydrophobicity, glucan production, sucrose-dependent and independent adherence. Its effect on biofilm architecture was also investigated with the help of confocal and scanning electron microscopy (SEM). Moreover, expression of genes involved in biofilm formation was also studied by quantitative RT- PCR. This study showed 50% reduction in adherence at concentrations 156 µg/ and 312.5 µg/ml of crude extract and ethanolic fraction respectively. However, the biofilm was reduced to 50% in the presence of crude extract (39.04 µg/ml) and ethanolic fraction (78.08 µg/ml). Furthermore, effective reduction was observed in the glucan synthesis and cell surface hydrophobicity. The qRT-PCR revealed significant suppression of the genes involved in its virulence. Confocal and scanning electron microscopy clearly depicted the obliteration of biofilm structure with reference to control. Hence, this study reveals the potential of E. officinalis fruit extracts as an alternative and complementary medicine for dental caries by inhibiting the virulence factors of Streptococcus mutans.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / isolation & purification
  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Adhesion / drug effects
  • Bacterial Outer Membrane Proteins / genetics
  • Bacterial Outer Membrane Proteins / metabolism
  • Biofilms / drug effects
  • Biofilms / growth & development
  • Chemical Fractionation
  • Dental Caries / microbiology*
  • Ethanol / chemistry
  • Fruit / chemistry
  • Humans
  • Hydrophobic and Hydrophilic Interactions
  • Microbial Sensitivity Tests
  • Phyllanthus emblica / chemistry*
  • Plant Extracts / isolation & purification
  • Plant Extracts / pharmacology*
  • Protein Binding
  • Quorum Sensing*
  • Solvents / chemistry
  • Streptococcus mutans / drug effects
  • Streptococcus mutans / growth & development
  • Streptococcus mutans / metabolism
  • Streptococcus mutans / physiology*
  • Transcriptome / drug effects

Substances

  • Anti-Bacterial Agents
  • Bacterial Outer Membrane Proteins
  • Plant Extracts
  • Solvents
  • Ethanol