No abstract available.
Erythrosine ; Light ; Photochemotherapy ; Streptococcus ; Streptococcus mutans ; Streptococcus sobrinus

OBJECTIVETo detect and distinguish Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus) quickly in epidemiology and investigate the distribution of S. mutans in the oral of children with rampant caries.

METHODSDesigned minor groove binder (MGB) probes according to the gtf gene of S. mutans and S. sobrinus. Detected 9 reference strains of Streptococcus mutans group by MGB probes in real time and after cultivation. Evaluated the results of these two methods. 92 dental plaques from pre-school children with rampant caries were detected in real time with MGB probes.

RESULTSThe primers could amplify the target sequences specificity and distinguished S. mutans and S. sobrinus from each other using MGB probes. Though the fluorescence occurred earlier in S. mutans than in S. sobrinus, they had the same results in nature. In 92 children with rampant caries, the detective ratio of S. mutans was 96.7% and that of S. sobrinus was 32.6%. All the samples which could detect S. sobrinus were positive for S. mutans.

CONCLUSIONThe primers and probe designed from gtf genes of S. mutans and S. sobrinus can amplify the target sequence and distinguish them from each other in real time.

Child ; Dental Caries ; Dental Plaque ; Humans ; Streptococcus mutans ; Streptococcus sobrinus

OBJECTIVES: This study was designed to evaluate the synergistic antibacterial effect of xylitol and ursolic acid (UA) against oral biofilms in vitro. MATERIALS AND METHODS: S. mutans UA 159 (wild type), S. mutans KCOM 1207, KCOM 1128 and S. sobrinus ATCC 33478 were used. The susceptibility of S. mutans to UA and xylitol was evaluated using a broth microdilution method. Based on the results, combined susceptibility was evaluated using optimal inhibitory combinations (OIC), optimal bactericidal combinations (OBC), and fractional inhibitory concentrations (FIC). The anti-biofilm activity of xylitol and UA on Streptococcus spp. was evaluated by growing cells in 24-well polystyrene microtiter plates for the biofilm assay. Significant mean differences among experimental groups were determined by Fisher's Least Significant Difference (p < 0.05). RESULTS: The synergistic interactions between xylitol and UA were observed against all tested strains, showing the FICs < 1. The combined treatment of xylitol and UA inhibited the biofilm formation significantly and also prevented pH decline to critical value of 5.5 effectively. The biofilm disassembly was substantially influenced by different age of biofilm when exposed to the combined treatment of xylitol and UA. Comparing to the single strain, relatively higher concentration of xylitol and UA was needed for inhibiting and disassembling biofilm formed by a mixed culture of S. mutans 159 and S. sobrinus 33478. CONCLUSIONS: This study demonstrated that xylitol and UA, synergistic inhibitors, can be a potential agent for enhancing the antimicrobial and anti-biofilm efficacy against S. mutans and S. sobrinus in the oral environment.
Biofilms* ; Hydrogen-Ion Concentration ; Polystyrenes ; Streptococcus ; Streptococcus mutans ; Streptococcus sobrinus ; Xylitol*

OBJECTIVETo evaluate the effects of Yili dark bee propolis on the main cariogenic biofilm and mechanisms.

METHODSSusceptibilities to the ethanolic extract of propolis against Streptococcus mutans (S. mutans), Streptococcus sobrinus (S. sobrinus), Streptococcus sanguis (S. sanguis), Actinomyces viscosus (A. viscosus), and Actinomyces naeslundii (A. naeslundii) were analyzed by crystal violet stain method to determine the minimum biofilm eradication concentration (MBEC). The biofilm was initially cultivated for 24 h. Subsequently, the propolis groups with different concentration MBEC and initial pH 7.0 were cultured for 24 h. Moreover, the pH value was measured to evaluate the acid-producing ability of the tested plaque biofilm. The effects of propolis on the insoluble extracellular polysaccharide synthesis of S. mutans biofilm were evaluated by anthrone method.

RESULTSThe MBEC of Yili propolis on S. mutans, S. sobrinus, S. sanguis, A. viscosus, and A. naeslundii were 6.25, 1.56, 3.13, 0.78, and 0.78 mg.mL-1, respectively. Propolis could decrease the ΔpH of the tested plaque biofilm, and the differences between the control and propolis groups were statistically significant (P<0.05). At MBEC, propolis could reduce the ability of S. mutans in synthesizing insoluble extracellular polysaccharides.

CONCLUSIONYili propolis demonstrate remarkable eradicative effects on the cariogenic plaque biofilm, showing inhibition of the synthesis of biofilm-produced acids and insoluble extracellular polysaccharides.

Actinomyces viscosus ; Animals ; Bees ; Biofilms ; Dental Plaque ; Propolis ; Streptococcus mutans ; Streptococcus sanguis ; Streptococcus sobrinus

Polyphenon 60 refers to the mixture of catechins present in green tea. The aim of this study was to investigate the antimicrobial activities of polyphenon 60 against 4 strains of Streptococcus mutans and 2 strains of Streptococcus sorbrinus, which are the major causative bacteria of dental caries. The minimum bactericidal concentration (MBC) values of polyphenon 60 for S. mutans and S. sobrinus were determined and the effect of biofilm formation inhibition of that was evaluated. The MBC value of polyphenon 60 against the bacterial strains was 2.5 mg/ml except for one particular strain, S. mutans KCOM 1128 for which the value was 1.25 mg/ml. The results of biofilm formation inhibition assay revealed that polyphenon 60 inhibited biofilm formation more than 90% at a concentration of 2.5 mg/ml. It was apparent that polyphenon exhibited biofilm formation inhibition activity along with bactericidal effect against S. mutans and S. sobrinus. Therefore, it is proposed that polyphenon 60 as one of the components of bactericidal agents could be useful in developing oral hygiene products, toothpaste or gargling solution.
Bacteria ; Biofilms ; Catechin ; Dental Caries ; Oral Hygiene ; Streptococcus mutans ; Streptococcus sobrinus ; Streptococcus ; Tea ; Toothpastes

This study was undertaken to develop species-specific forward and universal reverse PCR primers for the detection of Streptococcus sobrinus. These primers target the variable regions of the 16S ribosomal RNA coding gene (rDNA) and their specificity was tested against 10 strains of S. sobrinus strains and 20 different species of oral bacteria using serial dilutions of the purified genomic DNA of S.sobrinus ATCC 33478T . Our data show that species-specific amplicons were obtained from all the S. sobrinus strains tested but not from other species. Both direct and nested PCR could detect as little as 400 pg and 4 fg of genomic DNA from S. sobrinus ATCC 33478T , respectively. This result suggests that these PCR primers are highly specific and sensitive and applicable to the detection of S. sobrinus.
Bacteria ; Clinical Coding ; Collodion ; DNA ; Polymerase Chain Reaction ; RNA, Ribosomal, 16S ; Sensitivity and Specificity ; Streptococcus ; Streptococcus sobrinus

Ursolic acid is a triterpenoid compound present in many plants. This study examined the antimicrobial activity of ursolic acid against mutans streptococci (MS) isolated from the Korean population. The antimicrobial activity was evaluated by the minimum inhibitory concentration (MIC) and time kill curves of MS. The cytotoxicity of ursolic acid against KB cells was tested using an MTT assay. The MIC90 values of ursolic acid for Streptococcus mutans and Streptococcus sobrinus isolated from the Korean population were 2 microg/ml and 4 microg/ml, respectively. Ursolic acid had a bactericidal effect on S. mutans ATCC 25175T and S. sobrinus ATCC 33478T at > 2 x MIC (4 microg/ml) and 4 x MIC (8 microg/ml), respectively. Ursolic acid had no cytotoxic effect on KB cells at concentrations at which it exerted antimicrobial effects. The results suggest that ursolic acid can be used in the development of oral hygiene products for the prevention of dental caries.
Dental Caries ; Humans ; KB Cells ; Microbial Sensitivity Tests ; Oral Hygiene ; Streptococcus mutans ; Streptococcus sobrinus ; Triterpenes

OBJECTIVETo establish a simple and rapid method to detect Streptococcus mutans and streptococcus sobrinus simultaneously in human saliva.

METHODSChromosomal DNA from the bacteria was obtained by the extraction method with phenol-chloroform. A nested PCR method with two sets of primers specific for portions of the glucosyltransferase genes (gtfB of S. mutans and gtfI of S. sobrinus), was optimized to detect S. mutans and S. sobrinus from standard strains, clinical strains and directly in human saliva.

RESULTSThe first process of nested PCR was capable of amplifying DNA fragments specific for these species from chromosomal DNA extracted from 10(5) CFU cells of standard and clinical strains, or from 1 ml clinical saliva samples containing 10(5) CFU cells of either species. a second process of nested PCR, using the first PCR product as a template with new internal primers to detect 10(3) CFU of either streptococcal species in 1ml saliva samples.

CONCLUSIONNested PCR could detect S. mutans and S. sobrinus rapidly and simply in human saliva. This finding would be important to studies of elucidation the role of these two streptococcal species in the etiology of dental caries.

Humans ; Polymerase Chain Reaction ; Saliva ; microbiology ; Streptococcus mutans ; genetics ; isolation & purification ; Streptococcus sobrinus ; genetics ; isolation & purification

OBJECTIVETo establish a kind of molecular biology clinical detective method to cariogenic S. mutans.

METHODSUsing the coamplification of target and reference genes. One pair of specific primers were designed according to a portion of the dextranase (dexA) gene of S. mutans. The reference gene was plasmid pET23b DNA. The saliva samples of 196 children were quantitative detected. The PCR method was compared with the routine culture method.

RESULTSThe rate of S. mutans counts >/= 10(8) CFU/L (colony-forming unit per millilitre) saliva by quantitative PCR was 91.3%. The results of coincidence rate between the new method and the routine way was 94.9%.

CONCLUSIONSThe new quantitative detective method is fast and provides with high scoincidence rate and high specificity, so have extensive clinical practice foreground.

DNA Primers ; Humans ; Polymerase Chain Reaction ; Saliva ; Sensitivity and Specificity ; Streptococcus mutans ; genetics ; Streptococcus sobrinus ; genetics

OBJECTIVES: This study was conducted to determine whether Prunus mume extracts have an antimicrobial effect against Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus). METHODS: The study used crushed and dried Prunus mume, to which 80% methanol was added to obtain extracts. The extracts then underwent a demarcation process, sequentially using hexane, chloroform, and ethyl acetate, all of which have different polarities, followed by a reduction in pressure . The disc diffusion method was then used to measure the clear zone diameter to identify the antimicrobial effect of Prunus mume extracts using the different solvents. The methanol extracts that presented antimicrobial activity against S. mutans and S. sobrinus were then selected, and their optical densities (3, 6, 9, 12, and 24 h after cultivation) were measured to identify growth retardation effects based on extract concentration (0.01, 0.1, 1, and 5 mg/ml). RESULTS: A clear zone was observed in methanol and ethyl acetate for S. mutans when the antimicrobial effect of Prunus mume extracts of each solvent against oral microorganisms was measured via the disc diffusion method. A clear zone was observed in hexane, chloroform, methanol, and ethyl acetate, when the extracts were tested for antimicrobial activity against S. sobrinus. The extract concentration of 1 mg/ml retarded growth with a statistical significance (P<0.05) from 6 h onwards, as determined when the optical density was measured hourly and the growth curves of S. mutans and S. sobrinus were plotted. CONCLUSIONS: Prunus mume extracts retarded the growth of S. mutans and S. sobrinus with increase in time and concentration. Therefore, Prunus mume extracts hold the potential to be used for developing an oral antimicrobial agent to control dental caries.
Bacteria* ; Chloroform ; Dental Caries ; Diffusion ; Methanol ; Methods ; Prunus* ; Solvents ; Streptococcus mutans ; Streptococcus sobrinus