Growth Of Streptococcus Mutans Research Articles

ANTIBACTERIAL EFFECTIVENESS OF RAMBAI (Sonneratia Caseolaris) LEAVES EXTRACT AGAINST STREPTOCOCCUS MUTANS

Background: The 2018 Riskesdas data stated that dental caries prevalence in Indonesia was 88.8%. Dental caries is a multifactorial disease characterized by hard tissue damage to the enamel, dentin, and cementum of the teeth. One of the causes of caries is the presence of a microorganism called Streptococcus mutans. Rambai leaf extract (Sonneratia caseolaris) is a typical plant of South Kalimantan with content flavonoids, tripernoids, tannins, phenols, steroids that have antibacterial properties against the growth of Streptococcus mutans which can prevent caries. Purpose: To determine the difference in the effectiveness of the antibacterial extract of rambai leaves (Sonneratia caseolaris) against bacteria Streptococcus mutans in vitro. Methods: This research was a true experimental with a post-test-only design and a control group, using six treatment groups, namely 20%, 40%, 60%, 80%, positive control (povidone iodine 1%), and negative control (aquadest) respectively. Each treatment got 3 repetitions. The antibacterial test method used in this study was the liquid dilution method to determine the Minimun Inhibitory Concentration (MIC) by using Spectrophotometer and solid dilution to determine the Minimum Bactericidal Concentration (MBC) by using tools Colony Counter. Results: Based on the results and data analysis, it can be seen that the rambai leaf extract has a MIC of 20% and a MBC of 60%. Conclusion: Rambai leaf extract (Sonneratia caseolaris) can inhibit and have antibacterial activity against the growth of Streptococcus mutans. Keywords: Antibacterial, Rambai leaf extract, Streptococcus mutans

Potential of 10% propolis-based toothpaste on the inhibition of biofilm-forming bacteria growth in vitro

Aim of the study: To investigate the potential of 10% propolis-based toothpaste on inhibiting biofilm-forming bacteria growth in vitro. Material and method: Organoleptic properties are evaluated, considering color, odor, and taste. Antibacterial tests use a disc diffusion method against Streptococcus mutans, Staphylococcus aureus and Porphyromonas gingivalis bacteria, while cytotoxicity is assessed using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay on fibroblast cells. Statistical analysis involves mean ± standard deviation. The data were then tested using a one-way analysis of variance and Kruskal-Wallis, followed by post-hoc test (p < 0.05). Results: The organoleptic evaluation of 10% propolis toothpaste reveals a visually clear appearance, consistent orange flavor, and aroma lasting 30 days. Based on the antibacterial results, a 10% level of propolis toothpaste sample inhibited the growth of Streptococcus mutans, Staphylococcus aureus and Porphyromonas gingivalis bacteria. The post-hoc test showed that toothpaste demonstrated significant inhibition on S. mutans and S. aureus compared to the negative control (p < 0.05). The toothpaste showed a larger inhibitory zone towards P. gingivalis compared to the adverse control; however, no significant differences were observed (p > 0.05). Cytotoxicity assessment on fibroblast cells shows a high percentage (85.31%) of viable cells. The findings highlight the 10% of propolis toothpaste’s potential and non-toxic as oral care product. Conclusions: 10% propolis toothpaste inhibits S. mutans, S. aureus, P. gingivalis growth, and not toxic on fibroblast.

Antibacterial Activity and Shear Bond Strength of Orthodontic Adhesive Containing Various Sizes of Chitosan Nanoparticles: An In Vitro Study.

White spot lesions are common after orthodontic treatment. Chitosan nanoparticles (CS-NPs) have emerged as promising antibacterial agents that inhibit the growth of Streptococcus mutans. The aim of the study was to investigate the nano-effect of adhesives containing CS-NPs on S. mutansand their effects on shear bond strength. The inhibitory effects of two sizes of CS-NPs were assessed using the disc agar diffusion method. Four wells were created in the petri dishes, and each was inoculated with broth (negative control), chlorhexidine (positive control), CS-NPs (20 nm), or CS-NPs (131 nm). An Instron machine was used to evaluate shear bond strength by allocating 24 teeth into three groups, and all measurements were recorded in megapascals. Caries progression was assessed using the International Caries Detection and Assessment System and surface profilometry. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 27.0 (Released 2020; IBMCorp., Armonk, New York, United States) for a one-way ANOVA followed by Tukey's multiple comparison test. Disc agar diffusion showed a reduction in S. mutans in the CS-NPgroup compared to the control (p < 0.001), with no statistical significance between the sizes of 20 and 131 nm (p = 0.95). Regarding shear bond strength, no differences were recorded when adhesive-containing CS-NPs and the control were compared (p = 0.44). Additionally, no differences were found within the CS-NP groups (p = 0.91). Caries assessments showed excellent agreement, as indicated by a weighted kappa. Profilometry readings showed higher surface roughness in the control than in the CS-NP groups (p < 0.001), with no statistically significant difference between the CS-NP groups (p = 0.72). CS-NPs of both sizes tested had similar antibacterial effects. In addition, the incorporation of CS-NPs did not affect shear bond strength.

Probiotics, A New Frontier in Oral Health: Unraveling the Efficacy of Probiotic Metabolites vs. Chlorhexidine on Streptococcus mutans in Dental Plaque

The battle against dental caries has long been fought with conventional antimicrobial agents, with Chlorhexidine leading the charge. However, recent research has delved into the potential of probiotic metabolites as an alternative or adjunctive therapy in the quest for better oral health. In this editorial, we explore the emerging evidence surrounding the efficacy of probiotic metabolites compared to Chlorhexidine, specifically targetting local clinical isolates of Streptococcus mutans within dental plaque. Streptococcus mutans, a key player in the formation of dental plaque, has been a prime target for antimicrobial interventions due to its significant role in tooth decay. Chlorhexidine, a widely used antiseptic, has been a stalwart in dental care. However, its efficacy and potential side effects have prompted researchers to seek alternative approaches. Probiotic metabolites, byproducts of beneficial bacteria, have emerged as a promising avenue, with studies suggesting their ability to promote oral health by modulating the microbial balance.1 Recent studies have begun to unravel the intricate interactions between probiotic metabolites and Streptococcus mutans. These investigations have not only explored the direct antimicrobial effects but also the potential for probiotics to influence the overall microbial environment in the oral cavity. The comparison with Chlorhexidine, a gold standard in dental care, adds depth to our understanding of these alternative therapies.2 The evidence supporting the efficacy of probiotic metabolites in controlling Streptococcus mutans is not only encouraging but also challenges the status quo. A study by Gong SG et al. (2023) demonstrated that probiotic metabolites significantly reduced the growth of Streptococcus mutans in vitro, highlighting their potential as a potent antimicrobial agent.3 This finding is particularly promising given the increasing concerns about antibiotic resistance and the need for sustainable alternatives.&#x0D; Continued...

Comparative Assessment of Herbal Mouthwash with Chlorhexidine on Plaque Accumulation, Gingivitis, and Salivary Streptococcus mutans Growth

ABSTRACT Objectives: The goal of the current study was to assess the effectiveness of a commercially available herbal mouthwash with chlorhexidine on the number of Streptococcus mutans in the saliva, the condition of the gingival tissue, and plaque development. Materials and Methods: Twenty-two adults in all, ranging in age from 20 to 30, were divided into two groups at random. Throughout the 14-day clinical trial, Group A (11) and Group B (11) received 10 mL of test herbal mouthwash and chlorhexidine, respectively. Result: Herbal mouthwash was discovered to be equally as effective as chlorhexidine in lowering the salivary mutans streptococci count and in affecting plaque and gingival scores. Conclusion: Alternatives from the herbal world may show to be a reliable and secure therapy option.

Inhibition of Streptococcus mutans growth and biofilm formation through protein acetylation.

Numerous cellular processes are regulated in response to the metabolic state of the cell, and one such regulatory mechanism involves lysine acetylation. Lysine acetylation has been proven to play an important role in the virulence of Streptococcus mutans, a major cariogenic bacterial species. S. mutans' glucosyltransferases (Gtfs) are responsible for synthesizing extracellular polysaccharides (EPS) and contributing to biofilm formation. One of the most common nonsteroidal anti-inflammatory drugs is acetylsalicylic acid (ASA), which can acetylate proteins through a nonenzymatic transacetylation reaction. Herein, we investigated the inhibitory effects of ASA on S. mutans. ASA treatment was observed to impede the growth of S. mutans, leading to a reduction in the production of water-insoluble EPS and the formation of biofilm. Moreover, ASA decreased the enzyme activity of Gtfs while increasing the protein acetylation level. The in vivo anticaries efficacy of ASA has further been proved using the rat caries model. In conclusion, ASA as an acetylation agent attenuated the cariogenic virulence of S. mutans, suggesting the potential value of protein acetylation on antimicrobial and anti-biofilm applications to S. mutans.

Effect of peanut stilbenoids, arachidin-1 and arachidin-3, on Streptococcus mutans growth and acid production

In this study we evaluated the effect of prenylated peanut stilbenoids on the growth, biofilm accumulation and acid production of the dental caries pathogen Streptococcus mutans. Prior research with the non-prenylated stilbenes, resveratrol and piceatannol, has shown that these molecules are active against S. mutans. Here we sought to determine if the addition of a prenyl group to the stilbene backbone increased anti-S. mutans activities. Two prenylated stilbenes, arachidin-1 and arachidin-3, were produced using a peanut hairy root production system. Compared to resveratrol and piceatannol, both arachidin-1 and arachidin-3 led to greater inhibition of S. mutans planktonic growth. This effect also led to reduced biofilm formation, by inhibiting growth, instead of a specific action against biofilm cells. Lastly, sub-MIC concentrations of arachidin-3 reduced the acid production of S. mutans above the ‘critical pH’ that leads to tooth enamel erosion. In summary, stilbenoids have anti-S. mutans activity, and prenylation enhances this activity.

Isolation and detection of bacterial species on mitis salivarius bacitracin agar from the plaque samples of caries active children.

In cariology studies, mitis-salivarius-bacitracin (MSB) agar has been commonly considered as the selective medium for Streptococcusmutans growth. The present study was the part of a funded project (a noninferiority randomized controlled trial) which compared the efficacy of a plant extract-based mouth rinse with that of a fluoride mouth rinse on the S.mutans counts of the children. This study aimed to identify the frequency of detection of S.mutans and nonstreptococcal bacterial species from the dental plaque of caries active children using a combined technique of anaerobic culture and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. Caries-active children (8-12 years old) were enrolled from a pediatric dental outpatient department at a tertiary care hospital. From each participant, dental plaque samples were collected from carious surfaces under sterilized conditions and then subjected to anaerobic culture. After 48 h of incubation, the bacterial colonies were isolated by sub-culture and identified by the MALDI-TOF. In all, 13 different bacterial species were isolated from the MSB agar medium. Other than S.mutans species, colonies of bacterial species such as Veillonelladispar,Streptococcusanginosus, Veillonellaparvula, and Streptococcusgordonii were also frequently observed from the medium. The study concluded that several bacterial strains, both streptococcal and nonstreptococcal, could be isolated from the MSB agar medium; hence, this medium should no longer be considered selective medium for the culture of S.mutans in clinical and epidemiological studies.

Effectiveness of Wuluh Starfruit Leaf (Averrhoa bilimbi Linn) Extract on The Growth Streptococcus mutans In Vitro

Background: Starfruit (Averrhoa bilimbi Linn) contains vitamin C, flavonoids, tannins, and triterpenoids. This active compound is reported to prevent the growth of bacteria, including Streptococcus mutans. Objective: This study aims to determine the effectiveness of starfruit leaf extract (Averrhoa bilimbi Linn) in inhibiting Streptococcus mutans. Method: This type of research is true experimental with a post-test-only control design, where this research uses the Kirby-Baur diffusion method with samples of Streptococcus mutans bacteria and uses wuluh leaf extract with concentrations of 50%, 25%, 12.5%, 6 .25%, 3.125%. And DMSO solution as a negative control. Results: The formation of a clear zone shows the ability of starfruit leaf extract to inhibit the growth of Streptococcus mutans, with an average inhibitory diameter of 12.05 ± 0.7188, 9.50 ± 0.3464.8, 65 ± 0.2380, 7.80 ± 0.4546, 6.78 ± 0.8016. Conclusion: Based on the research results, it can be concluded that Averrhoa bilimbi Linn can inhibit Streptococcus mutans.

THE EFFECTIVENESS OF CEMCEM (Spondiaspinnata (L.f) Kurz) LEAF EXTRACT IN INHIBITING THE GROWTH OF Streptococcus mutans

Introduction: Dry socket is post-tooth extraction pain characterized by partial or complete loss of blood clots in the alveolar socket. One of the management of dry socket is by using antibiotic therapy. Inappropriate use of antibiotics in addition to being economically wasteful can also cause bacterial resistance to antibiotics. The use of herbal ingredients such as Cemcem (Spondiaspinnata (L.f) Kurz) is one solution. Cemcem leaves are thought to have antibacterial effects because they contain flavonoids, tannins and saponins. This study aims to determine the inhibition of cemcem leaf extract (Spondias pinnata (L.f) Kurz) against the growth of Streptococcus mutans. Materials and methods: The research method used is the Kirby Bauer method which is a sensitivity test with the agar diffusion method using the disc diffusion technique. In the Kirby Bauer sensitivity test using selective media, namely Muller Hinton Blood Agar media, the inhibition zone created is characterized by a clear zone around the disc. The data obtained were analyzed using the Kruskall Wallis test to determine whether or not there was a significant difference then continued with the Mann Whitney U - Test. Results: Cemcem leaf extract (Spondias pinnata (L.f) Kurz) with a concentration of 60% and 70% can inhibit the growth of Streptococcus mutans better than positive control and 80% concentration. Conclusion: 60% concentration of cemcem leaf extract is more effective in inhibiting the growth of Streptococcus mutans than 70% and 80% concentrations.

Antibacterial Efficacy of Miana Leaves Extract against Streptococcus Mutans

Introduction: Streptococcus mutans is the main bacterium that causes dental caries. Miana leaves antimicrobial compounds such as flavonoids, alkaloids, tannins, and saponins are expected to have antibacterial properties against the growth of Streptococcus mutans. Purpose: To determine the antibacterial effect of miana leaves extract on Streptococcus mutans growth. Methods: This study was an in vitro laboratory experimental study with a post-test only control group design. The treatment groups consisted of Miana leaves extract using concentrations of 3,125%, 6,25%, 12,5%, and 25%, positive control (0.2% chlorhexidine) and negative control (dimethyl sulfoxide/DMSO). Inhibition zone test was done using disc diffusion method. Results: The  results  showed  that  each  concentration  of Miana leaves extract  had antibacterial properties.  The largest  diameter  of  the  inhibitory  zone was  at  25%  concentration, but significant smaller than 0.2% chlorhexidine. Conclusion: Miana leaves extract had an antibacterial effect against Streptococcus mutans.

Antibacterial and biolarvicidal activity of extracts of ethanol of Goniothalamus macrophyllus leaves and roots

Tendani (Goniothalamus macrophyllus) is empirically often used by Dayak people as a mosquito repellent by burning the stem bark and roots which have the ability as anti-bacterial. The objective of this research is to evaluate the antibacterial and biolarvicidal properties of ethanol extracts of Goniothalamus macrophyllus’s leaves and roots. The research method used qualitative method with colour phytochemical test, antibacterial test, and larvicidal test. Based on the study of active compounds contained in G. macrophyllus, the results of colour phytochemical tests of ethanol extracts of leaves and roots all contain compounds of the alkaloid, flavonoid, triterpenoid/steroid, saponin, tannin and phenol groups. The results of the antibacterial tests on the leaves and roots have a strong ability to inhibit the growth of Candida albicans, Propionibacterium acne and Streptococcus mutans. The highest larval mortality rate in the biolarvicide test was obtained in the root part of tendani with a concentration of 15% at 88%. The conclusion of the study is that the leaves and roots of the tendani plant have potential as antibacterial and biolarvicidal.

Inhibitory effects of Bacillus velezensis ID-A01 supernatant against Streptococcus mutans

BackgroundDental caries is a chronic oral disease caused by microbial infections, which result in erosion of the dental enamel and cause irreversible damage. Therefore, proper disease management techniques and the creation of an environment that prevents intraoral growth and biofilm formation of Streptococcus mutans in the early stages, are crucial to prevent the potential progression of dental plaque to disease. Here, we aimed to investigate antimicrobial and antibiofilm effects of the Bacillus velezensis ID-A01 supernatant (ID23029) against S. mutans, and its inhibitory effects on acidogenesis.ResultsA killing kinetics assay showed a peak lethality percentage of 94.5% after 6 h of exposure to ID23029. In sucrose-exposed conditions, ID23029 inhibited lactic acid formation, preventing the pH from falling below the threshold for enamel demineralization, and inhibited up to 96.6% of biofilm formation. This effect was maintained in the presence of lysozyme. Furthermore, ID23029 retained up to 92% lethality, even at an intraoral concentration at which lysozyme is ineffective against S. mutans.ConclusionsThis study demonstrates the potential of the B. velezensis ID-A01 supernatant for the prevention and treatment of dental caries. Its eventual use in dental practice is encouraged, although further studies are required to confirm its beneficial effects.

Antibacterial Effect of Three Kinds of Methylene Blue Photosensitizers Mediated Photodynamic Therapy on Streptococcus Mutans

In order to study the antibacterial effect of methylene blue (MB) photosensitizer-mediated photodynamic therapy (PDT) on Streptococcus mutans in aqueous solvent form, SDS solution form and their mixed form, the influence of MB-PDT on antibacterial effect of Streptococcus mutans in different dosage forms was analyzed. The number of colonies after and before photodynamic therapy mediated by MB-mediated photodynamic therapy was compared by in vitro viable bacterial colony counting method. Negative control group, light alone group, water dosage MB group, mixed dosage MB group, SDS dosage MB group, water dosage MB-PDT group, mixed dosage MB-PDT group and SDS dosage MB-PDT group were set up respectively the effect of different dosage forms of photosensitizers on the antibacterial effect of Streptococcus mutans was analyzed by counting and comparing in vitro for 24 hours. Through in vitro culture experiment, it was found that the number of colonies in water dosage form, mixed dosage form and SDS dosage form MB-PDT group was less than that in water dosage form, mixed dosage form and SDS dosage form MB. The proportion of viable bacteria in SDS MB group was significantly lower than that in water and mixed MB groups, and the antibacterial rate of SDS MB-PDT group was significantly higher than that in water and mixed MB-PDT group. These results indicated that MB-PDT could significantly inhibit the proliferation and growth of Streptococcus mutans. Among them, SDS MB-PDT group had more obvious antibacterial effect on Streptococcus mutans than water MB-PDT group and mixed MB-PDT group, but there was no significant difference in antibacterial effect between water MB-mediated PDT group and mixed MB-mediated PDT group.

Chemical composition of essential oil from Lindera subumbelliflora Kosterm and its effect on the susceptibility and biofilm activities of Candida albicans and Streptococcus mutans

The chemical composition of the essential oil of Lindera subumbelliflora (Lauraceae) was investigated for the first time. The essential oil was obtained by hydrodistillation and fully characterised by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The antifungal activity of L. subumbelliflora essential oil was tested against Candida albicans and Streptococcus mutans using the broth microdilution assay, whereas the microbial biofilms were determined using a semi-quantitative static biofilm. A total of 28 components (99.6%) were successfully identified, which were characterised by β-eudesmol (14.6%), cis-α-bergamotene (11.0%), α-copaene (8.5%), dodecen-1-ol (8.5%), and (E)-nerolidol (8.3%). The essential oil exhibited activity against Candida albicans and Streptococcus mutans with MIC values of 250 and 500 µg/mL, respectively. The essential oil increased the biofilm of Candida albicans by 38.25%, however, decreased the biofilm of Streptococcus mutans by 47.89% when treated with 500 µg/mL. Thus, the essential oil has a promising application in dentistry via inhibition of the growth of Candida albicans and Streptococcus mutans. However, the antibiofilm activity of the essential oil is only applicable for cariogenic Streptococcus mutans.

THE INHIBITORY POWER OF PINEAPPLE HUMP ETHANOL EXTRACT TOWARD THE GROWTH OF STREPTOCOCCUS MUTANS

Background:This study aimed to investigate inhibitory powers of etanol extract from pinnaple hump with concentrations of 7,5%, 10%, 15%,  20%, 25%, and 30% toward the growth of  Streptococcus mutans bacteria. Methods: Pineapple hump extract was made using maseration technique with ethanol 96% as a solvent. Agar well diffusion method was used in order to investigate the inhibitory ability of pineapple humpagainst Streptococcus mutans. Few (20-100 µl) volume of the pineapple hump extract solution from each of concentrations was placed into each of well on blood agar in petri dishes had contained Streptococcus mutans then incubated for 24 hours at 370C temperature, lastly the measurement of inhibition power was measured with caliper. Results: The results showed that pineapple hump extract with concentrations of 7,5%, 10%, 15%, 20%, 25%, and 30% could inhibit the growth of Streptococcus mutans bacteria. Pineapple hump extracts with concentrations of 7,5% and 10% have moderate inhibition power (average diameter respectively are 7,45 mm and 8,58 mm), pineapple hump extracts with concentrations of 15%, 20%, 25%, and 30% have strong inhibition power (average diameter respectively are 10,16 mm, 11,33 mm, 13,33 mm, and 14,83 mm). Conclusions: The Conclusion is: ethanol extract of pineapple hump has inhibitory power toward the growth of Streptococcus mutans within range of moderate category and strong category

Antimicrobial Effects of Edible Mixed Herbal Extracts on Oral Microorganisms: An In Vitro Study.

Background and Objectives: The oral cavity is inhabited by pathogenic bacteria, whose growth can be inhibited by synthetic oral drugs, including antibiotics and other chemical compounds. Natural antimicrobial substances that elicit fewer negative side effects may serve as alternatives to synthetic agents for long-term use. Thus, the aim of this study was to evaluate the effects of edible mixed herbal extracts on the growth of oral pathogenic bacteria. Materials and Methods: The yield of each herbal extract was as follows: 5% Schizonepeta tenuifolia Briq (STB), 10.94% Mentha piperascens (MP), 5.47% Acanthopanax sessiliflorus Seem (AS), and 10.66% Glycyrrhiza uralensis (GU). The herbal extracts used included 0.5 mg/mL STB, 1.5 mg/mL MP, 1.5 mg/mL AS, and 2.0 mg/mL GU. Antimicrobial tests, morphological analyses (using scanning electron microscopy), microbial surface hydrophobicity measurements, and oral malodor reduction tests were performed using each extract. Statistical analyses were performed with IBM® SPSS® (version 24), using paired t-tests. Results: The mixed herbal extracts significantly inhibited the growth of Streptococcus mutans, Enterococcus faecalis, Candida albicans, and Porphyromonas gingivalis compared to the control (p < 0.001). Scanning electron microscopy results further revealed altered cellular morphology in the groups treated with the mixed herbal extracts. Additionally, the hydrophobicity assay results showed that the mixed herbal extracts reduced the oral adhesion capacities of bacteria (p < 0.001). Administration of the mixed herbal extracts also reduced the levels of volatile sulfur compounds, the main contributors to oral malodor (p < 0.001). Conclusions: Edible mixed herbal extracts can effectively eliminate oral pathogens and may be useful for improving oral health. The herbal extracts used were effective against all species of oral pathogens studied in this report.

Virulence factors analysis and determination of the suitable chemical agent to inhibit Streptococcus mutans growth and biofilm formation

Streptococcus mutans is one of the most important causes of tooth decay and oral diseases, and it has received wide attention from researchers worldwide. The present work aimed to investigate, evaluation and comparisons effect of the antimicrobial and anti-biofilm property of some commercial compounds (chlorhexidine, hyaluronic acid, sodium fluoride and silver nanoparticles) against oral bacteria pathogens of S. mutans. In this work, S. mutans ATCC 25175 was used and its virulence factors were analyzed using Seed Viewer and The Comprehensive Antibiotic Resistance Database (CARD). The antibacterial susceptibility testing (AST) confirms effects of chlorhexidine mouthwash on S. mutans ATCC 25175 beggar than all components. The minimum inhibitory concentration (MIC) minimum bactericidal concentration (MBC) and Minimum biofilm inhibition concentration (MBIC) of the commercial compounds were determined. The statistical analysis was performed using One-Way ANOVA (Tukey test). The VITEK2system was used to confirm the biochemical features of S. mutans ATCC 25175 and susceptibility testing was done to compare the results with Seed Viewer and CARD analysis. The findings showed that The MICs, MBCs, and MBIC means of chlorhexidine against S. mutans ATCC 25175 was 0.0079, 0.0038, and 0.0039 μg/mL respectively, where its biological activity was significantly (P < 0.05) higher compared to other commercial compounds included in this study. The S. mutans strain used in this study showed sensitivity to all tested antibiotics and the Seed Viewer and CARD reported that it has several virulence factors such as adhesion genes (hsp33, Cpa, PrtF, PrtF2, MsmRL, Nra, SOF, LepAL, Spy0135, and RofA) and antibiotic-resistant genes (vanY, vanT, and mdeA). This study concluded that chlorhexidine was the best in inhibiting S. mutans growth as well as preventing biofilm formation, and the study recommends further investigation about antibiotic resistance genes and susceptibility profile.

Antibacterial Effects of Ramulus mori Oligosaccharides against Streptococcus mutans.

Ramulus mori has been widely used in traditional Chinese medicine because of its physiological activities, including antibacterial, anti-inflammatory, and antioxidant activities. Antimicrobial properties of Ramulus mori extract have been well described. However, no information is available regarding on Ramulus mori oligosaccharides (RMOS). The aim of this study was to investigate the effects of RMOS on the growth and virulence properties of the cariogenic bacterium Streptococcus mutans. The effects of RMOS on the biofilm structure and virulence gene expression of S. mutans were also evaluated, and the results were compared with the effects of commercial prebiotic galactooligosaccharides. RMOS were found to have an antibacterial effect against S. mutans, resulting in significant reductions in acid production, lactate dehydrogenase activity, adhesion, insoluble extracellular polysaccharide production, glucosyltransferase activity, and biofilm formation in a dose-dependent manner. Moreover, the biofilm structure was visibly damaged. A quantitative real-time PCR assay revealed downregulation of virulence gene-regulated acid production, polysaccharide production, adhesion, biofilm formation, and quorum sensing. These findings suggest that RMOS may be a promising natural product for the prevention of dental caries.

Comparing the Antibacterial Effect of Coated and Impregnated Flexible Dentures with Magnesium Oxide Nanoparticles against Streptococcus mutans

(1) Background: This study compares the antibacterial effect of coated and impregnated flexible dentures with magnesium oxide nanoparticles (MgONPs) against Streptococcus mutans. (2) Methods: the study used flexible denture material discs. The experimental groups were uncoated dics (control), 5% MgONPs coated discs (coated), and 5% MgONPs impregnated discs (impregnated). The homogenous distribution of MgONPs within the matrix was determined using scanning electron microscopy (SEM), and surface roughness and modulus elasticity were also measured. The antibacterial efficacy was tested against Streptococcus mutans in suspension and biofilm. The adhesion of microorganisms was assessed using an adherence assay test, optical light microscopy, and turbidity test. (3) Results: The nanoparticles were successfully coated or impregnated on the substrate and caused a significant increase in roughness. The effect of 5% MgONPs was significant (p &lt; 0.05). The flexible denture samples whether coated or impregnated with 5% MgONPs effectively inhibited the growth of microorganisms. The Streptococcus mutans growth was 2.5 folds higher in control compared to coated samples, while Streptococcus mutans growth was 1.5 folds higher in control compared to impregnated samples. Furthermore, this study confirmed there was a homogenous distribution of MgONPs for both coated and impregnated groups. (4) Conclusions: It was found that addition of 5% MgONPs can prevent the attachment of Streptococcusn mutans to flexible removable denture material. Additionally, the antibacterial effect was higher in the coated-samples compared to impregnated-samples.