• Journal of dental hygiene science
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• v.23 no.2
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• pp.103-111
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• 2023

Background: Some studies confirm the reduction of the number of Streptococcus mutans in saliva and dental plaque by Lactobacillus, however, these effects are not always confirmed in in vitro and clinical studies, and only the risk of dental caries has been reported. Our in vitro study aimed to reveal microbial and biochemical changes in the single cultures of S. mutans, Lactobacillus casei and Aggregatibactor actinomycetemcomitans and co-cultures of S. mutans and L. casei or A. actinomycetemcomitans according to sucrose concentration. We also aimed to confirm the anti-oral bacterial and anti-biofilm activities of L. casei and A. actinomycetemcomitans against S. mutans according to sucrose concentration. Methods: S. mutans (KCCM 40105), L. casei (KCCM 12452), and A. actinomycetemcomitans (KCTC 2581) diluted to 5×10⁶ CFU/ml were single cultured, and L. casei or A. actinomycetemcomitans applied at concentrations of 10%, 20%, 30% and 40% to S. mutans were co-cultured with selective medium containing 0%, 1% and 5% sucrose at 36.5℃ for 24 hours. Measurements of bacterial growth value and acid production, disk diffusion and biofilm formation assays were performed. Results: In the medium containing sucrose, the bacterial growth and biofilm formation by S. mutans, L. casei, and A. actinomycetemcomitans were increased. In contrast, 30% and 40% of L. casei in the medium containing 0% sucrose showed both anti-oral bacterial and anti-biofilm activities. This implies that L. casei can be used as probiotic therapy to reduce S. mutans in a 0% sucrose environment. Conclusion: The concentration of sucrose in the oral environment is important for the control of pathogenic bacteria that cause dental caries and periodontitis. To apply probiotic therapy using L. casei for S. mutans reduction, the concentration of sucrose must be considered.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.191-195
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• 2002

In previous reports the authors have screened the inhibition effects of marine algae extracts on halitosis, and demonstrated that a brown algae, Eisenia bicyclis (' Daehwang') possess not only strong deodorant effect bug also considerable anticariogenic activities. In this study, we screened antibacterial effects of various marine algae, and measured minimum inhibitory concentration (MIC) value of them against mutans streptococci in vitro. Among the 27 species of marine algae, $80\%$ ethanol extract of dried sea-mustard, Laminaria japonica ('Dasima') showed the strongest inhibition activity against Streptococcus mutans KCTC 3300. The extracts of Ulva lactuca ('Galparae'), Codium fragile ('Cheonggak'), Ecklonia cava ('Gamtae'), E. stolonifera ('Gompi') and Undalia Pinnatifida ('Miyeok') showed slightly weaker inhibitory potency than L. japonica. Differences of MIC values in $80\%$ ethanol extract of some species of marine algae were observed depending on test bacterial species, i.e., S. mutans KCTC 3300 or S. sobrinus KCTC 3307. Eighty percent ethanol extract of dried L japonica was fractionated with diethyl ether, chloroform, ethyl acetate, n-buthanol and water successively, The ether-soluble fraction had inhibitory effect on S. mutans KCTC 3300, however the inhibitory effects were not found in the other fractions. The MIC values of $80\%$ ethanol extract and ether fraction were 180 and 105 $\mu$g/mL respectively, while no significant inhibition activity of water-soluble fraction was found even when the fraction was added up to 5,500 $\mu$g/mL.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.3
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• pp.427-436
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• 2005

Topical application of APF gel can increase the surface roughness of resin composites and the roughened surfaces may allow increased bacterial accumulation and surface staining. Resin specimens of two proprietary resin composites, Filtek Z250(FZ) and Filtek Supreme Universal(FS), and experimental resin composites containing 0%, 3%, 6% nanofillers(E0, E3, E6) were fabricated and divided into two groups of the same number; APF treatment group and no treatment group. The amount of S. mutans adhered to specimens and the mean surface roughness(Ra) were measured. The results were as follows; 1. In no treatment group, the amount of S. mutans adhered to FS was the smallest. It was significantly different from those of FZ, E3, E6(p<0.05) although it was not significantly different from that of E0(p>0.05). 2. For all resin composites used, the amount of S. mutans adhesion in APF treatment group was significantly greater than that in no treatment group(p<0.05). 3. In APF treatment group, the amount of S. mutans adhesion was significantly different between materials(p<0.05), and increased in order of FS, FZ, E0, E3 and E6. 4. Difference of the surface roughness(Ra) between materials was not statistically significant in both no treatment group and APF treatment group(p>0.05)

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.2
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• pp.149-157
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• 2022

The aim of this study was to evaluate the effects of erythrosine-mediated photodynamic therapy (PDT) on Streptococcus mutans biofilm recovery by counting its colony-forming units (CFUs) and via confocal laser scanning microscopy analysis at different time points following PDT. In PDT, photosensitizer was an erythrosine. S. mutans ATCC25175 biofilms were irradiated using an LED curing light. Chlorhexidine (CHX) was used as positive control. After each antimicrobial treatment, samples were cultured to allow biofilm recovery. Viability was measured by calculating the CFU counts after treatment and after every 3 hours for up to 24 hours. Immediately after treatment, the PDT and CHX groups showed equally significant decreases in S. mutans CFU counts compared to the negative control. After 12 hours of reculture, the PDT group showed no significant difference in the decrease in CFU count compared to the negative control, whereas the CHX group showed significantly lower CFU counts throughout the 24-hour period. Erythrosine-mediated PDT can effectively inhibit S. mutans biofilm formation. However, biofilm recovery occurred earlier in the CHX group after PDT. This study provides insights into the clinical effectiveness of PDT in preventing dental caries.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.4
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• pp.549-557
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• 2000

Dental caries is a bacterial disease of the dental hard tisssus, characterized by a localized, progressive, molecular disintegration of tooth structure. The action of Leuconostoc lactis 51 about plaque formation and replication by Streptococcus mutans was studied as follows. 1. Lower amount of plaque was produced at the mixed culture of S. mutans and L. lactis 51 than S. mutans alone on the wires in the beaker. 2. Fewer cells of S. mutans were replicated at the mixed culture of S. mutans and L. lactis 51 than S. mutans alone. 3. In M17Y broth, viable cells of S. mutans and L. lactis 51 increased for 12 hours, and decreased for 24 hours. In M17YS broth, viable cells of S. mutans showed time-dependent decrease at mixed culture of S. mutans and L. lactis 51. 4. The culture supernatant of L. lactis 51 didn't inhibit the replication of S. mutans and the formation of artificial plaque. 5. Sucrose and frutose were extracted from the culture supernatant of L. lactis 51 in M17YS broth. These results suggest that L. lactis 51 isolated from the oral cavity inhibits the replication of S. mutans and the formation of artificial plaque.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.5
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• pp.1148-1153
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• 2007

Streptococcus mutans is considered one of the primary etiologic agents of dental caries. we studied the effect of the ethanol extracts of Tribuli fructus (T. fructus) on the growth, biofilm formation, acid production, adhesion and insoluble glucan synthesis of S. mutans. The ethanol extracts of T. fructus showed concentration dependent inhibitory activity against the growth and acid production of S. mutans, and produced significant inhibition at the concentration of 0.025, 0.05, 0.1, 0.2, 0.3, 0.5 mg/ml compared to the control group. In the biofilm assay, the ethanol extracts of T. fructus inhibited formation of biofilm synthesized by S. mutans at the concentration of 0.05 mg/ml. The extracts markedly inhibited S. mutans adherence to HA treated with saliva, and cell adherence was repressed by more than 50% at the concentration 0.05 mg/ml. On the activity of glucosyltransferase which synthesizes water insoluble glucan form sucrose, ethanol extract of T. fructus showed more than 10% inhibition over the concentration of 0.025 mg/ml. Hence, we conclude that T. fructus might be a candidate of anticaries agent. Further studies are necessary to clarify the active constituents of T. fructus responsible for such biomolecular activities.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.522-526
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• 1999

Bactericidal effects of chitosans with varying molecular weight $(10,000{\sim}170,000)$ were investigated for Streptococcus mutans, a primary causative bacterium of dental caries. The molecular weight of chitosan was a significant contributor to the bactericidal effect, and a chitosan having approximately 30,000 of molecular weight exhibited the highest bactericidal effects on S. mutans. Treatment of chitosan resulted in leaking intracellular protein and nucleic acid out of S. mutans cells. In addition, the divalent cations such as $Ca^{2+}\;and\;Mg^{2+}$ were also significantly released out of the cell. Visible damage of chitosan treated cells was observed by transmission electron microscopy (TEM), in which the cell wall was notably distorted and cytoplasmic membrane was separated from the cell wall. The results suggested that the bactericidal effect of chitosan on S. mutans was attributable to both leakage of intracellular materials and structural disintegration of cell wall.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.2
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• pp.370-374
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• 2005

Streptococcus mutans (S. mutans) is known as the causative bacterial playing the most important role informing plaque and it is being noticed as major causative bacteria of dental caries. Therefore, development of more effective, substantial and safe preventive agent against dental caries and periodontal disease is honestly required. The present study was designed to investigate the effect of Cyperus rotundus (Cyperaceae) methanol extracts on the growth, acid production, adhesion, and insoluble glucan synthesis of S. mutans. The methanol extract of C. rotundus showed concentration dependent inhibitory activity against the growth and acid production of S. mutans, and produced significant inhibition at the concentration of 0.5, 1, 2 and 4 mg/ml compared to the control group. The extracts markedly inhibited S. mutans adherence to HA treated with saliva, and cell adherence was repressed by more than 50% at the concentration of 0.5 mg/ml and complete inhibition was observed at the concentration of 4 mg/ml. On the activity of glucosyltransferase which synthesizes water insoluble glucan from sucrose, methanol extract of C. rotundus showed more than 10% inhibition over the concentration of 2 mg/ml. Thus, the application of C. rotundus can be considered a useful and a practical method for the prevention of dental caries.

• Journal of Periodontal and Implant Science
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• v.20 no.2
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• pp.162.2-162.2
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• 1990

• KSBB Journal
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• v.8 no.1
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• pp.75-82
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• 1993

The inhibitory effect of cacao bean husk (CBH) extract on glucosyltransferase(GTasc) from Streptococcus mutans B13 was investigated. Water solube extract from CBH showeda sarong inhibitory effect (88-89%) on GTase from Streptococcus mutans Bl3. GTase inhibitors from sequential extraction by hot water or water-methanol had the strongest inhibition. Sources, fermentation, and types of solvents and fumigation processes did not influence the effect. These active compounds proved to be polyphones through acid hydrolytic analysis of the precipitates by ammonium sulfate or ethanol and proteinase K. It was also confirmed by additional column chromatography of Sephadex G-50, Sephadex LH-20 and DEAE-Sephdex A-50.