Inhibitory effect of Streptococcus salivarius K12 and M18 on halitosis in vitro.

BACKGROUND: The aim of the study was to observe the antimicrobial activity of Porphyromonas gingivalis and Treponema denticola as well as the effect on reducing volatile sulfur compounds (VSCs). MATERIALS AND METHODS: After P. gingivalis and T. denticola were cultured with or without Streptococcus salivarius K12 and M18, VSCs were measured by Oral Chroma. In order to analyze the mechanism for malodor control, the antimicrobial activity of S. salivarius K12 and M18 against P. gingivalis and T. denticola was assessed. SPSS 21.0 was used for data analysis with the Kruskal-Wallis and Jonckheere-Terpstra tests. Mann-Whitney test was applied for post hoc analysis. RESULTS: P. gingivalis and T. denticola VSC levels were reduced by high concentrations of S. salivarius K12 and M18 during coculture. The concentrations were lower than those of single culture (p < .05). An antimicrobial effect was detected on P. gingivalis, and T. denticola by 50% S. salivarius K12 and M18. The spent culture medium and whole bacteria of S. salivarius K12 and M18 reduced the levels of VSCs below the amount in a single culture of P. gingivalis and T. denticola (p < .05). CONCLUSION: S. salivarius K12 and M18 decreased the levels of VSCs originating from P. gingivalis and T. denticola.

Efficacy of Moringa oleifera Leaf Extracts against Cariogenic Biofilm.

Moringa oleifera leaves are beneficial for human health. Dental caries is closely related with cariogenic biofilm, which is an oral biofilm containing a high proportion of Streptococcus mutans. The purpose of this study was to investigate the antimicrobial effects of the M. oleifera leaf extracts on S. mutans and formation of cariogenic biofilm. Extract from M. oleifera leaves was derived using distilled water (DW) and ethyl alcohol (EtOH). S. mutans susceptibility assays were performed for each extract. Cariogenic biofilm was formed with or without DW and EtOH extract, and cariogenic biofilm was treated with both extracts. The biofilm was observed by confocal laser microscopy, and the bacteria in the biofilm were counted. Both extracts showed antimicrobial activity against S. mutans and inhibited formation of cariogenic biofilm. The EtOH extracts exhibited anti-biofilm activity. M. oleifera leaves may be potential candidates to prevent dental caries.

Efficacy of ß-caryophyllene for periodontal disease related factors.

OBJECTIVE: This study aimed to investigate the antimicrobial activity of ß-caryophyllene against periodontopathogens as well as its inhibitory effects on the expression of inflammatory cytokines and production of volatile sulfur compounds by lipopolysaccharide and periodontopathogenic enzymes, respectively. DESIGN: The antimicrobial activity of ß-caryophyllene againstPorphyromonas gingivalis, Tannerella forsythia, and Treponema denticola was investigated via a susceptibility assay using a microplate reader. THP-1 cells were treated with lipopolysaccharide in the presence or the absence of ß-caryophyllene, and the expression and production of inflammatory cytokines were then analyzed by a real-time reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay. After fluorescence-labelling lipopolysaccharide, the effect of ß-caryophyllene on the binding of lipopolysaccharide to the cell wall was investigated via flow cytometry. The spent culture media of P. gingivalis was shaken with or without ß-caryophyllene and gaseous volatile sulfur compounds (VSCs) were measured by a gas chromatograph. RESULTS: ß-caryophyllene showed strong the antimicrobial activity against periodontopathogens. It also reduced lipopolysaccharide-induced expression and production of cytokines, thereby inhibiting the binding of lipopolysaccharide-binding to toll-like receptors by interfering with the complex of lipopolysaccharide and CD14 or lipopolysaccharide-binding protein. ß-caryophyllene also inhibited the emission of gaseous VSCs produced byP. gingivalis. CONCLUSIONS: ß-caryophyllene may improve periodontal health via antimicrobial activity against periodontopathogens, reducing inflammation caused by lipopolysaccharide, and by neutralizing VSCs.

Inhibitory effects of ß-caryophyllene on Streptococcus mutans biofilm.

OBJECTIVE: The biofilm of Streptococcus mutans is associated with induction of dental caries. Also, they produce glucan as an extracellular polysaccharide through glucosyltransferases and help the formation of cariogenic biofilm. ß-caryophyllene has been used for therapeutic agent in traditional medicine and has antimicrobial activity. The purpose of this study was to investigate the effect of ß-caryophyllene on S. mutans biofilm and the expression of biofilm-related factor. DESIGN: The susceptibility assay of S. mutans for ß-caryophyllene was performed to investigate inhibitory concentration for S. mutans growth. To evaluated the effect of ß-caryophyllene on S. mutans biofilm, ß-caryophyllene was treated on S. mutans in the various concentrations before or after the biofilm formation. Live S. mutans in the biofilm was counted by inoculating on Mitis-salivarius agar plate, and S. mutans biofilm was analyzed by confocal laser scanning microscope after staining bacterial live/dead staining kit. Finally, the expression of glucosyltransferases of S. mutans was investigated by real-time RT-PCR after treating with ß-caryophyllene at the non-killing concentration of S. mutans. RESULTS: The growth of S. mutans was inhibited by ß-caryophyllene in above concentration of 0.078%, S. mutans biofilm was inhibited by ß-caryophyllene in above 0.32%. Also, 2.5% of ß-caryophyllene showed anti-biofilm activity for S. mutans biofilm. ß-caryophyllene reduced the expression of gtf genes at a non-killing concentration for S. mutans. On the basis on these results, ß-caryophyllene may have anti-biofilm activity and the inhibitory effect on biofilm related factor. CONCLUSIONS: ß-caryophyllene may inhibit cariogenic biofilm and may be a candidate agent for prevention of dental caries.