• Archives of Pharmacal Research
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• v.15 no.3
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• pp.239-241
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• 1992

The methanol extract of Cinnamoni Cortex showed antibacterial action against cariogenic bacterium, Streptococcus mutans OMZ 176. The active principle of the extract was identified to be trans-cinnamaldehyde, which was bactericidal in the minimal inhibitory concentration (MIC) of $100\;\mu$g/ml against the strain. From the results of antibacterial activity of cinnamaldehyde and its derivatives, the acrolein group in the cinnamaldehyde was elucidated to be an essential element for the activity.

• Imaging Science in Dentistry
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• v.37 no.1
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• pp.35-43
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• 2007

Purpose : To observe direct effect of irradiation on cariogenic Streptooccus mutans. Materials and Methods : S. mutans GS5 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40Gy. Viability and changes in antibiotic sensitivity, morphology, transcription of virulence factors, and protein profile of bacterium after irradiation were examined by pour plate, disc diffusion method, transmission electron microscopy, RT-PCR, and SDS-PAGE, respectively. Results : After irradiation with 10 and 20Gy, viability of S. mutans was reduced. Further increase in irradiation dose, however, did not affect the viability of the remaining cells of S. mutans. Irradiated 5. mutans was found to have become sensitive to antibiotics. In particular, the bacterium irradiated with 40Gy increased its susceptibility to cefotaxime, penicillin, and tetracycline. Under the transmission electron microscope, number of morphologically abnormal cells was increased as the irradiation dose was increased. S. mutans irradiated with 10 Gy revealed a change in the cell wall and cell membrane. As irradiation dose was increased, a higher number of cells showed thickened cell wall and cell membrane and Iysis, and appearance of ghost cells was noticeable. In RT-PCR, no difference was detected in expression of gtfB and spap between cells with and without irradiation of 40Gy. In SDS-PAGE, proteins with higher molecular masses were gradually diminished as irradiation dose was increased. Conclusion : These results suggest that irradiation affects the cell Integrity of S. mutans, as observed by SDS-PAGE, and as manifested by the change in cell morphology, antibiotic sensitivity, and eventually viability of the bacterium.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1142-1149
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• 2004

Streptococcus mutans has the capacity of inducing dental caries. Thus, to develop a novel way of preventing dental caries, a cell wall hydrolase-producing strain was isolated and its characteristics were investigated. Among 200 alkalophilic strains isolated from soil, 8 strains exhibited lytic activities against Streptococcus mutans. However, strain YU5215 with the highest cell wall hydrolase activity was selected for further study. Strain YU5215 was identified as a novel strain of Bacillus based on analyzing its 16S rDNA sequence and Bergey's Manual of Systematic Bacteriology, and thus designated as Bacillus mutanolyticus YU5215. The optimal conditions for the production of the cell wall hydrolase from Bacillus mutanolyticus YU5215 consisted of glucose ($0.8\%$), yeast extract ($1.2\%$), polypeptone ($0.5\%$), $K_{2}HPO_{4}\;(0.1\%$), $MgSO_{4}{\cdot}7H_{2}O$ ($0.02\%$), and $Na_{2}CO_{3}\;(1.0\%$) at pH 10.0. Bacillus mutanolyticus YU5215 was cultured at 30^{circ}C for 72 h to produce the cell wall hydrolase, which was then purified by acetone precipitation and CM-agarose column chromatography. The molecular weight of the lytic enzyme was determined as 22,700 Da by SDS-PAGE. When the cell wall peptidoglycan of Streptococcus mutans was digested with the lytic enzyme, no increase in the reducing sugars was observed, while the free amino acids increased, indicating that the lytic enzyme had an endopeptidase-like property. The amino terminus of the cell wall peptidoglycan digested by the lytic enzyme was determined as a glutamic acid, while the lytic site of the lytic enzyme in the Streptococcus mutans peptidoglycan was identified as the peptide linkage of L-Ala and D-Glu.

• Journal of Korean society of Dental Hygiene
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• v.19 no.4
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• pp.467-477
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• 2019

Objectives: The aim of this study is to investigate the mechanical properties and antibacterial effects on Streptococcus mutans of composite resins containing phytoncide. Methods: Phytoncide was mixed with commercial composite resins at 0 (control), 1.25, 2.5, 3.75, and 5.0 weight percentage (wt%). Mechanical properties related to composite resins such as surface hardness, depth of cure, and flexural strength were measured. Antibacterial effects of composite resins were analyzed by using Streptococcus mutans (ATCC 25175). The results were analyzed by one-way analysis of variance followed by Tukey's test (p<0.05). Results: Composite resins that contain low wt% of phytoncide demonstrated no significant difference in surface hardness, depth of cure, and flexural strength (p>0.05). However, composite resins that contain high wt% of phytoncide had significantly decreased mechanical properties (p<0.05). In terms of antibacterial effects, composite resins containing phytoncide inhibited the growth of S. mutans. Conclusions: Our findings suggest that novel composite resins containing phytoncide have effective antibacterial properties while maintaining the originally important mechanical features of composite resins.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.899-903
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• 2008

This study was conducted in order to elucidate the optimum conditions for the extraction of clove that can be used to elicit antibacterial activity against Streptococcus mutans using the evolutionary operation (EVOP)-factorial design technique. Higher antibacterial activity was achieved in a higher extraction temperature of $80^{\circ}C$ ($r=0.7983^{**}$) and in a longer extraction time of 26 hr ($r=0.6867^*$). Antibacterial activity was not effected by differentiation of ethanol concentration in the extraction solvent (r=-0.0683). The maximum antibacterial activity of clove against S. mutans as determined by the EVOP-factorial design technique was obtained at an extraction temperature of $80^{\circ}C$, an extraction time of 26 hr and a 50% ethanol concentration. Furthermore, the population of S. mutans decreased from an initial concentration of 6.850 to 4.195 log CFU/mL in the third set that is more than 2.6 log cycles by EVOP-factorial design technique.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1566-1569
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• 2016

Three flavonoids were isolated from dried flowers of Sophora japonica using repetitive column chromatography and high-performance liquid chromatography. The flavonoids were identified as rutin (1), quercetin-3'-O-methyl-3-O-α-ʟ-rhamnopyranosyl(1 → 6)-β-ᴅ-glucopyranoside (2), and quercetin (3) on the basis of spectroscopic analysis and comparison of values reported in the literature. These compounds inhibited the action of sortase A (SrtA) from Streptococcus mutans, a primary etiologic agent of human dental caries. The onset and magnitude of inhibition of saliva-induced aggregation of S. mutans treated with compound 1 was comparable to that of untreated S. mutans with a deletion of the srtA gene.

• Journal of Korean society of Dental Hygiene
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• v.18 no.1
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• pp.9-18
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• 2018

Objectives: Pleurotus eryngii is used both for edible and medicinal purposes, and has a physiological activity. The purpose of this study is to investigate the antibacterial effect of Pleurotus eryngii against six oral pathogens (Staphylococcus aureus, Streptococcus criceti, Streptococcus mutans, Streptococcus ratti, Streptococcus sobrinus, and Actinomyces viscosus). Methods: The antibacterial activities of various extracts of Pleurotus eryngii were examined by disc diffusion assay and minimum inhibitory concentration (MIC). The disc diffusion assay was performed by putting a paper disc soaked in extracts on plates inoculated bacterial cultures. The MIC of these extracts was determined by using a broth microdilution assay at a concentration ranging between 0.03 mg/ml to 15.00 mg/ml. The growth inhibition effect of extracts was measured at 600 nm for 24 hrs. Results: The antibacterial activity was confirmed against all six tested bacteria at Pleurotus eryngii ethyl acetate extract by the disc diffusion method. Acetone extract showed the antibacterial activity only against 4 strains containing Streptococcus criceti, Streptococcus mutans, Streptococcus ratti, and Actinomyces viscosus. In ethanol extract, no activity was observed against other strains except Staphylococcus aureus. MIC values of ethyl acetate extract were the same, 7.50 mg/ml in all tested bacteria. Conclusions: Pleurotus eryngii exhibited the antibacterial activity against oral pathogens (Staphylococcus aureus, Streptococcus criceti, Streptococcus mutans, Streptococcus ratti, Streptococcus sobrinus, and Actinomyces viscosus). Thus, Pleurotus eryngii may be considered as a natural antibacterial agent for treatment of dental diseases.

• Food Science of Animal Resources
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• v.25 no.4
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• pp.500-506
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• 2005

This study was carried out to obtain knowledges on the survival of Streptococcus mutans in the yoghurt added with green tea powder. The growth inhibition of green tea powder on the food borne pathogens and oral bacteria was measured by total microbial count, Among the tested food borne pathogens, the growth of Staphylococcus aureus and Salmonella enteritidis were not significantly affected by the addition of green tea powder, but green tea powder showed the growth inhibition effect on Escherichia coli O157:H7. The number of surviving Streptococcus mutans cell was decreased by $0.56\~0.99log$ cycle after 24 hem incubation by the addition of $0.5\~2.5\%$ green tea powder in the medium. And also the viable cell count of surviving Streptococcus mutans cells (initial inoculum $3.4\times10^7CFU/mL$) were decreased to $1.4\times10^4\~7.2\times10^4 CFU/mL$ after 48 hours incubation when $0.5\~2.5\%$ green tea powder were added to the drinkable yoghurt, Growth of Streptococcus mutans was strongly inhibited by the addition and incubation of green tea powder for 48 hum in the yoghurt.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.1
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• pp.16-24
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• 2001

The purpose of this study was to evaluate the specificity, sensitivity, and diagnostic power of caries activity test using laser fluorescence. The subjects of this study were 50 children of $7\sim9$ years old. Fluorescence from initial carious lesion of teeth illuminated by an argon laser(480nm) was observed and photographed with barrier filter. Visual examination for the dDfFtT rate and Streptococcus mutans colony counting was done to evaluate correlation with caries activity test using laser fluorescence. Data analysis was accomplished by Axelsson's method. The results from the present study can be summarized as follows: 1. There was positive correlation $(\gamma=0.48)$ between laser fluorescence test and Streptococcus mutans count. And also positive correlation $(\gamma=0.39)$ exists between laser fluorescence test and dDfFtT rate (P<0.01). 2. Positive correlation $(\gamma=0.27)$ between Streptococcus mutans colony count and dDfFtT rate was found(P<0.05). 3. When dDfFtT rate was defined to standard testing method, the specificity, senstivity, and diagnostic power of laser fluorescence test were 44.4%, 85.7%, and 87.8%. 4. When dDfFtT rate was defined to standard testing method, the specificity, senstivity, and diagnostic power of S. mutans colony counting were 77.8%, 92.9%, 84.8%. 5. When S. mutans colony counting was defined to standard testing method, sensitivity, specificity and diagnostic power of laser fluorescence test were 40.0%, 84.8%, 95.1%. In regard to above results, laser fluorescence test considered to be accurate and reliable method for determining caries activity because of it's close relationship with caries susceptibility test and caries experience measurements. And it was also considered to be practical because it would be simple, inexpensive, and time saving method.

• Restorative Dentistry and Endodontics
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• v.13 no.1
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• pp.53-67
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• 1988

An investigation was carried out to compare the pulp responses against a few type of composite and streptococcus mutans contamination under the zinc oxide eugenol cement, and also confirmed pulpal responses of various composites with or without base. Seventy eight teeth from 6 dogs were employed and divided into 6 groups. Class V cavities were prepared on each tooth routinely with low speed dental engine. Paper disc about 0.3mm thick was immersed in the BHI broth in which streptococcus mutans had been enriched and the disc was inserted on the cavity floor prior to filling. Scotch bond puls Silux as Bis-GMA system composite resin and Helimolar as urethane system composite resin were adopted. Control group: Zinc-Oxide Eugenol cement filling Experimental groups: Group 1. Scotch bond + Silux filling with Dycal base Group 2. Heliomolar filling with Dycal base Group 3. Scotch bond + Silux filling without base Group 4. Heliomolar filling without base Group 5. Streptococcus mutans application. All cavities were sealed with thick ZOE cement to avoid marginal leakage. Postoperative intervals of 1, 2, 3, 4, 5 and 6 weeks teeth were carefully extracted, processed and stained with Hematoxylin and Eosin. The results were as follows: 1. S. mutans application group and composites without any base showed more severe pupal response than control group and dyca based groups. 2. The experimental group of S. mutans application showed severe response in the early stage compared to the two groups of composite resin without base, but no significant difference was found following periods. 3. The difference of pulpal response is not significant between Bis-GMA system and urethane system. 4. Streptococcus mutans application group and composites without base groups showed the evidence of histologic recovery at the six week cases and the large amount of reparative dentin was the prominent feature. 5. Pulp responses against every material were inclined to normal according to the time elapsed.