IADR Abstract Archives
Assessment of Lactobacillus plantarum Biosurfactants to Fight Endodontic Infection
Objectives: The inability of current endodontic procedures to prevent/eradicate bacterial biofilms persisting within the root canal complexities comprises a major challenge. It has been reported that tensioactive microbe-derived molecules termed biosurfactant (BS) can exhibit antimicrobial and/or anti-adhesive properties. The aim of this study is to assess the antimicrobial and anti-adhesive abilities of biosurfactant against potential biofilm forming endodontic pathogens.
Methods: Screening assays identified a potential anti-microbial activity for Lactobacillus plantarum following its co-culture with endodontic pathogens within the Streptococcus anginosus group (SAG; S.anginosus, S.intermedius, S.constellatus) and Enterococcus faecalis. A cell-bound BS was extracted from L.plantarum into PBS overnight with constant agitation and partially biochemically and physically characterized. Commercially sourced Rhamnolipid from Pseudomonas aeruginosa, was also examined as a proven BS with broad range antimicrobial activity. Effects of BS on growth of endodontic pathogens was performed to determine the minimal inhibitory concentration (MIC). Anti-adhesive activity of BS was determined on glass or acrylic discs. Maximum tolerable concentrations of BS by pulpal fibroblasts was determined by trypan blue viability staining.
Results: Demonstrating biosurfactant properties, L.plantarum-derived biosurfactant lowered surface tension of PBS by 17mN/m2. Biochemical analysis using SDS-PAGE with silver staining, anthrone assay and Fourier Transform Infra-Red spectroscopy revealed a glycoprotein nature. L.plantarum BS demonstrated minimal antimicrobial activity against endodontic pathogens, but at 20mg/mL greatly reduced adhesion of SAG and E.faecalis. The maximal tolerable concentration of rhamnolipid by pulp fibroblasts was 0.1mg/mL. At these sub-cytotoxic concentration, rhamnolipid was shown to be bacteriostatic against SAG, but not E.faecalis (MIC determined to be 50mg/mL) and showed antiadhesive activity against S.anginosus and S.intermedius.
Conclusions: The combined antimicrobial and anti-adhesive activities of the two biosurfactants examined identify them good candidates for consideration as an alternative therapeutic approach for the prevention and/or treatment of root canal infection.
Methods: Screening assays identified a potential anti-microbial activity for Lactobacillus plantarum following its co-culture with endodontic pathogens within the Streptococcus anginosus group (SAG; S.anginosus, S.intermedius, S.constellatus) and Enterococcus faecalis. A cell-bound BS was extracted from L.plantarum into PBS overnight with constant agitation and partially biochemically and physically characterized. Commercially sourced Rhamnolipid from Pseudomonas aeruginosa, was also examined as a proven BS with broad range antimicrobial activity. Effects of BS on growth of endodontic pathogens was performed to determine the minimal inhibitory concentration (MIC). Anti-adhesive activity of BS was determined on glass or acrylic discs. Maximum tolerable concentrations of BS by pulpal fibroblasts was determined by trypan blue viability staining.
Results: Demonstrating biosurfactant properties, L.plantarum-derived biosurfactant lowered surface tension of PBS by 17mN/m2. Biochemical analysis using SDS-PAGE with silver staining, anthrone assay and Fourier Transform Infra-Red spectroscopy revealed a glycoprotein nature. L.plantarum BS demonstrated minimal antimicrobial activity against endodontic pathogens, but at 20mg/mL greatly reduced adhesion of SAG and E.faecalis. The maximal tolerable concentration of rhamnolipid by pulp fibroblasts was 0.1mg/mL. At these sub-cytotoxic concentration, rhamnolipid was shown to be bacteriostatic against SAG, but not E.faecalis (MIC determined to be 50mg/mL) and showed antiadhesive activity against S.anginosus and S.intermedius.
Conclusions: The combined antimicrobial and anti-adhesive activities of the two biosurfactants examined identify them good candidates for consideration as an alternative therapeutic approach for the prevention and/or treatment of root canal infection.