Oral Pathogenic Bacteria Research Articles

MIC and MBC of red fruit extract (Pandanus conoideus Lam) against periodontal pathogens bacteria

There are only few studies on the antibacterial activity of red fruit extract (Pandanus conoideus Lam) against oral pathogenic bacteria. Thus, this study aims to determine the effectiveness of red fruit extracts by looking at the Minimum inhibitory Concentrations (MIC) and Minimal Bactericidal Concentrations (MBC) against periodontal pathogenic bacteria. The subjects of this study were Streptococcus mutans (ATCC 25175), Fusobacterium nucleatum (ATCC 25586), and Porphyromonas gingivalis (ATCC 33277). The antibacterial effectiveness of red fruit extract was tested by the liquid dilution method (microdilution). The data were analyzed using the one-way ANOVA test followed by a double comparison test with the Post Hoc Least Significance Different (LSD) test method. The red fruit extract effectively inhibited and eliminated test bacteria (p <0.05). Our study showed that the red fruit extracts at a concentration of 20% could inhibit the growth of Streptococcus mutans and Porphyromonas gingivalis, which was determined as the MIC strength of 80% as MBC of both bacteria tested. Furthermore, red fruit extract at the concentration of 10% showed an inhibitory effect on the growth of Fusobacterium nucleatum, which was determined as MIC of Fusobacterium nucleatum and the strength of 40% as MBC of Fusobacterium nucleatum. The red fruit extracts were significantly effective against the growth of Streptococcus mutans, Fusobacterium nucleatum, and Porphyromonas gingivalis provide essential information for further in vivo clinical studies to determine the exact dosage and clinical effectiveness of periodontal disease.

Proton Pumping ATPases: Rotational Catalysis, Physiological Roles in Oral Pathogenic Bacteria, and Inhibitors.

Proton pumping ATPases, both F-type and V/A-type ATPases, generate ATP using electrochemical energy or pump protons/sodium ions by hydrolyzing ATP. The enzymatic reaction and proton transport are coupled through subunit rotation, and this unique rotational mechanism (rotational catalysis) has been intensively studied. Single-molecule and thermodynamic analyses have revealed the detailed rotational mechanism, including the catalytically inhibited state and the roles of subunit interactions. In mammals, F- and V-ATPases are involved in ATP synthesis and organelle acidification, respectively. Most bacteria, including anaerobes, have F- and/or A-ATPases in the inner membrane. However, these ATPases are not believed to be essential in anaerobic bacteria since anaerobes generate sufficient ATP without oxidative phosphorylation. Recent studies suggest that F- and A-ATPases perform indispensable functions beyond ATP synthesis in oral pathogenic anaerobes; F-ATPase is involved in acid tolerance in Streptococcus mutans, and A-ATPase mediates nutrient import in Porphyromonas gingivalis. Consistently, inhibitors of oral bacterial F- and A-ATPases, such as phytopolyphenols and bedaquiline, strongly diminish growth and survival. Herein, we discuss rotational catalysis of bacterial F- and A-ATPases, and discuss their physiological roles, focusing on oral bacteria. We also review the effects of ATPase inhibitors on the growth and survival of oral pathogenic bacteria. The features of the catalytic mechanism and unique physiological roles in oral bacteria highlight the potential for proton pumping ATPases to serve as targets for oral antimicrobial agents.

Effects of hydrogen rich water and pure water on periodontal inflammatory factor level, oxidative stress level and oral flora: a systematic review and meta-analysis

Hydrogen rich water (HRW) was used as an auxiliary treatment for periodontitis and peri-implantitis due to its good antioxidant properties. However, the stability of artificially added active hydrogen was far less than that of pure natural active hydrogen, which greatly reduced active hydrogen molecules number in HRW. Meanwhile, the effect of HRW was relatively slow. Finally, long-term drinking of HRW may cause abnormal liver function. Hence, this study sought to summarize and analyze the effects of HRW on oral inflammation and oral flora in various studies to determine whether HRW can be used to inhibit dental plaque formation and aliviate oral inflammation. Randomized controlled trials (RCTs) of HRW and pure water (PW) in the treatment of periodontal diseases published before March 2022 in the PubMed, Web of science, EMBASE, Cochrane, China Knowledge Resource Integrated, Wanfang, and Weipu databases were searched. Changes in the inflammatory factor levels, oxidative stress response, and oral flora were summarized and used as outcome indicators. The quality of included studies was assessed by Cochrane risk of bias assessment tool, and the standardized mean differences (SMD) and the 95% confidence intervals (CIs) were calculated using Review Manager 5.3. In total, 17 studies, comprising 304 subjects, were included in this meta-analysis. Among them, 5 studies had a high risk of bias, and the rest had a certain risk of bias, thus, the total risk of bias was medium to low. The levels of interleukin (IL)-1β (SMD =-0.73; 95% CI: -1.29 to -0.18; P=0.009), tumor necrosis factor alpha (SMD =-2.51; 95% CI: -3.56 to -1.46; P<0.00001), IL-6 (SMD =-1.31; 95% CI: -1.96 to -0.67; P<0.0001), 8-hydroxyguanosine (SMD =-1.61; 95% CI: -2.35 to -0.87; P<0.0001), and reactive oxygen metabolites (SMD =-0.49; 95% CI: -0.91 to -0.06; P=0.02) in the HRW group decreased significantly, while the glutathione peroxidase level increased (SMD =2.5; 95% CI: 1.85 to 3.15; P<0.00001). Additionally, HRW was shown to effectively inhibit oral pathogenic bacteria activity (SMD =-0.91; 95% CI: -1.16 to -0.66; P<0.00001). HRW effectively inhibits the inflammatory reaction, oxidative stress level, and bacterial proliferation activity in patients with periodontal disease.

Association between Periodontitis and Inflammatory Bowel Disease- Review of Current Literature on the Biologic Plausibility

Periodontitis, a chronic inflammatory disease of the supporting tissues of teeth, is etiologically associated with a subset of pathogenic organisms that thrive in the anoxic niche provided by the diseased periodontal pockets. These anaerobic gram-negative organisms resident in plaque biofilm and causing an overwhelming chronic inflammatory response in periodontal tissues have also been associated with other systemic chronic inflammatory diseases like cardiovascular, renal, and adverse pregnancy outcomes as per literature being published for the past twenty years or more. This paper aims to provide an overview on the biological plausibility of a strong association between systemic seeding of pathogenic oral bacteria and chronic bowel diseases like Inflammatory Bowel Diseases by reviewing recent literature from open-source journals on the same topic. Knowledge of the association between oral bacteria and gut inflammatory diseases will help in broadening the preventive and therapeutic options available currently by suggesting measures to suppress the systemic hyper-immune response.

In vitro evaluation of the antibacterial and cytotoxic activities of the Euclea natalensis crude extract and fractions against oral infection agents

ObjectiveThis study aimed (i) to evaluate the antibacterial and cytotoxic activities of the crude extract and fractions obtained from Euclea natalensis A.D.C. roots against bacteria that cause periodontal disease and caries and (ii) to identify the isolated compounds. DesignThe minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of the extract and fractions were determined by the microplate dilution assay. The cytotoxicity of the extract and fractions was evaluated by using the XTT colorimetric assay and normal human fibroblast cells (GM07492A, lung fibroblasts). The compounds present in the most promising fraction were determined by qualitative analysis through liquid chromatography coupled to mass spectrometry (HPLC–MS-ESI). ResultsThe MIC results ranged from 25 to > 400 μg/mL for the extract and from 1.56 to > 400 μg/mL for the fractions. To evaluate cytotoxicity, the tested concentrations of the extract and fractions ranged from 19.5 to 2500 μg/mL; IC50 values between 625 and 1250 μg/mL were obtained. Analysis of the main bioactive fraction by HPLC–MS-ESI identified phenolic acids, coumarins, naphthoquinones, lignans, and fatty acids. ConclusionsThe E. natalensis root extract and fractions displayed good antibacterial activity against periodontal pathogenic and cariogenic bacteria. The antibacterial activity may be due to compounds present in the extract and fractions, which also showed low cytotoxicity to normal human cells. These data are relevant and encourage further research into this plant species, which may contribute to the discovery of new herbal medicines that will help to mitigate the problems caused by oral pathogenic bacteria.

The antibacterial activity of nasturtium officinale extract on common oral pathogenic bacteria.

The oral cavity is colonized by a myriad of microorganisms, some of which are proven to be detrimental to human health. There have been numerous efforts to control the population of pathogenic agents in the oral cavity, including the usage of natural phytochemicals obtained from medicinal plants. Nasturtium officinale has long been used in traditional medicine for the management of hypertension, respiratory infections, and hyperglycemia, and its effectiveness against some microbes has been reported. To evaluate antimicrobial properties of a hydro-alcoholic extract of N. officinale against common oral pathogens namely Streptococcus mutans, Staphylococcus aureus, Lactobacillus acidophilus, Enterococcus faecalis, and Pseudomonas aeruginosa. Experimental laboratory study. Different dilutions of N. officinale hydro-alcoholic extract were the test solutions, the positive control was a bacterial suspension in sterile phosphate-buffered saline, whereas the negative control was the herbal extract only, without any bacterial inoculation. Hydro-alcoholic extract of N. officinale prepared in five different concentrations (105, 52.5, 26.25, 13.12, 6.56 mg.mL-1) was tested separately against Streptococcus mutans, Lactobacillus acidophilus, Pseudomonas aeruginosa, Enterococcus faecalis, and Staphylococcus aureus in a test of microdilution assay. Spectrophotometry was used to assess bacterial growth after 24 and 48 h. The data of optical absorbance reads from spectrophotometry were analyzed using repeated-measures analysis followed by Least Significant Differences (LSD) post hoc. The highest growth inhibitory effect against S. mutans, E. faecalis, and S. aureus was observed at a concentration of 13.12 mg.mL-1; for L. acidophilus and P. aeruginosa, the most significant inhibition was observed at a concentration of 105 mg.mL-1. N. officinale extract effectively inhibited the growth of the tested oral bacteria at different concentrations but was more effective against S. mutans, E. faecalis, and S. aureus and so may be effective in managing some oral microbial infections.

Inhibitory Effect of Bacillus licheniformis Strains Isolated from Canine Oral Cavity.

Bacillus licheniformis is used in a broad spectrum of areas, including some probiotic preparations for human and veterinary health. Moreover, B. licheniformis strains are known producers of various bioactive substances with antimicrobial and antibiofilm effects. In searching for new potentially beneficial bacteria for oral health, the inhibitory effect of B. licheniformis strains isolated from canine dental biofilm against pathogenic oral bacteria was evaluated. The antimicrobial effect of neutralized cell-free supernatants (nCFS) was assessed in vitro on polystyrene microtiter plates. Furthermore, molecular and morphological analyses were executed to evaluate the production of bioactive substances. To determine the nature of antimicrobial substance present in nCFS of B. licheniformis A-1-5B-AP, nCFS was exposed to the activity of various enzymes. The nCFS of B. licheniformis A-1-5B-AP significantly (p < 0.0001) reduced the growth of Porphyromonas gulae 3/H, Prevotella intermedia 1/P and Streptococcus mutans ATCC 35668. On the other hand, B. licheniformis A-2-11B-AP only significantly (p < 0.0001) inhibited the growth of P. intermedia 1/P and S. mutans ATCC 35668. However, enzyme-treated nCFS of B. licheniformis A-1-5B-AP did not lose its antimicrobial effect and significantly (p < 0.0001) inhibited the growth of Micrococcus luteus DSM 1790. Further studies are needed for the identification of antimicrobial substances.

Prevalence of Methicillin and β-Lactamase Resistant Pathogens Associated with Oral and Periodontal Disease of Children in Mymensingh, Bangladesh.

Oral and periodontal diseases (OPD) is considered one of the main problems of dentistry worldwide. This study aimed to estimate the prevalence of oral and periodontal pathogenic bacteria along with their antimicrobial resistance pattern in 131 children patients aged between 4–10 years who attended in Mymensingh Medical College Hospital during October 2019 to March 2020. OPD pathogens were identified through isolation, cultural and biochemical properties, and nucleic acid detection. The isolates were subjected to antimicrobial susceptibility to 12 antibiotics commonly used in dentistry. In addition, the isolates were analyzed molecularly for the presence of six virulence and three antibacterial resistance genes. Five pathogens were identified, of which Staphylococcus aureus (S. aureus) (49%) and S. salivarius (46%) were noticed frequently; other bacteria included S. mutans (16.8%), S. sobrinus (0.8%) and L. fermentum (13.7%). The virulence genes—clumping factor A (clfA) was detected in 62.5% isolates of S. aureus, and gelatinase enzyme E (gelE) gene was detected in 5% isolates of S. salivarius, while other virulence genes were not detected. All the tested isolates were multidrug-resistant. The overall prevalence of MDR S. aureus, Streptococcus spp. and L. fermentum was 92.2%, 95.1% and 100%, respectively. It was observed that a high proportion of isolates were found resistant to 5–8 antibiotics. A majority of S. aureus, Streptococcus spp., and L. fermentum isolates tested positive for the β−lactamase resistance genes blaTEM and cfxA, as well as the methicillin resistance gene mecA. Phylogenetically, the resistance genes showed variable genetic character among Bangladeshi bacterial pathogens. In conclusion, S. aureus and S. salivarius were major OPD pathogens in patients attended in Mymensingh Medical College Hospital of Bangladesh, and most were Beta-lactam and methicillin resistant.

Clinical effect of compound lidocaine cream on oropharyngeal flora under general anesthesia

To observe the effect of compound lidocaine cream on oropharyngeal flora under general anesthesia, the front-end tracheal tube or laryngeal mask was coated with 410 cases under general anesthesia were chosen as endotracheal intubation group (T) and Laryngeal mask group (L) from Jan, 2022 to June, 2022. Both were separately grouped into blank control (M), liquid paraffin oil (P) and Compound lidocaine cream (C). Based on the grouping, patients’ throat swab samples were collected for bacterial culture through tracheal catheter. Oral normal flora and pathogenic bacteria from M and P were compared and P &gt;0.05 was considered statistically non-significant. By comparison of C, T and L group, their oral normal flora and pathogenic bacteria were obviously restrained. In conclusion, compound lidocaine cream was coated on tracheal tube or laryngeal mask for patients under general anesthesia. This method will be helpful to improve oral problems from pathogenic bacteria and also to inhibit oral normal flora.

Development and Standardization of Toothpaste Incorporating Moringa oleifera Leaf Extract

Dental hygiene is an important aspect to control oral infections such as tooth decay and gum diseases. And in novel dentistry, herbal toothpaste is more acceptable and safer with minimum side effects over synthetic preparation. The current study was envisioned to formulate herbal toothpaste by incorporating the leaf extract of Moringa oleifera and standardizing it as per the Sri Lankan standard requirements. The toothpaste base formulation was optimized and incorporated with M. oleifera leaf extract to develop the Moringa toothpaste. The net mass and extrusive content, consistency, cohesiveness, stability, tube inertness, moisture content, and volatile matter, pH of the Moringa toothpaste were determined to standardize the formulated toothpaste as per the requirement of SLS Standard (275:2014). The anti-bacterial efficacy of Moringa toothpaste was evaluated against Staphylococcus aureus, an oral pathogenic bacterium. The contents of elements present in the M. oleifera leaf powder that are known to improve oral health including Ca, K, and Mg were also determined. The leaf extract percentage was selected as 5% (w/w) to be incorporated into the optimized toothpaste base formulation. The formulated herbal toothpaste complied with the requirements of SLS Standard (275:2014) indicating acceptable net mass (23.6 g), extrusive content (49.96%), consistency (present), cohesiveness (passed), stability (stable formulation), moisture, and volatile matter content (43.16%) and pH (6.26). In an antibacterial assay, the Moringa toothpaste showed a significant zone of inhibition of 2±0.029 cm indicating its antibacterial potential against S. aureus to provide tooth and oral hygiene and to prevent various dental diseases. The contents of Ca, Mg, and K were found as 0.6%, 1.7%, and 0.14% respectively. The formulation development and standardization of M. oleifera based herbal toothpaste, having the potential to improve oral health is reported for the first time through this study. This new product can be introduced as an innovative approach to incorporate plants like M. oleifera in oral care products.&#x0D; Keywords: Antibacterial activity, Evaluation, Moringa toothpaste, Moringa oleifera leaf powder, Standardization

Application of green silver nanoparticles synthesized from the red seaweeds Halymenia porphyriformis and Solieria robusta against oral pathogenic bacteria by using microscopic technique.

Aqueous extracts of two red seaweeds Halymenia porphyriformis and Solieria robusta were used to synthesize green silver nanoparticles. These biogenic nanoparticles were tested against four strains of oral pathogenic bacteria which cause tooth decay or cavities. Staphylococcus aureus (MT416445), Streptococcus viridans (MT416448), Lactobacillus acidophilus (MT416447) and Lactobacillus brevis (MT416446) were used. Characterization of AgNPs was done by UV-Visible spectroscopy, SEM, XRD and FTIR. XRD analysis revealed the crystalline nature of the particles. The size analysis by XRD of the green AgNPs by H. porphyriformis indicated it had smaller particles, 15.23 nm, when compared to AgNPs by S. robusta (17 nm). Both green synthesized silver nanoparticles showed moderate antibacterial activity against all strains of bacteria, except L. acidophilus. Both particles showed their maximum zone of inhibition against L. acidophilus at a lower concentration of 50 and 100 μg. However, it was concluded that silver nanoparticles of H. porphyriformis are more effective than that of S. robusta due to their smaller size.

Periodontitis Salivary Microbiota Aggravates Ischemic Stroke Through IL-17A.

Although epidemiological studies suggest that periodontitis is tightly associated with ischemic stroke, its impact on ischemic stroke and the underlysing mechanisms are poorly understood. Recent studies have shown that alteration in gut microbiota composition influences the outcomes of ischemic stroke. In the state of periodontitis, many oral pathogenic bacteria in the saliva are swallowed and transmitted to the gut. However, the role of periodontitis microbiota in the pathogenesis and progression of ischemic stroke is unclear. Therefore, we hypothesized that the periodontitis salivary microbiota influences the gut immune system and aggravates ischemic stroke. Mice receiving gavage of periodontitis salivary microbiota showed significantly worse stroke outcomes. And these mice also manifested more severe neuroinflammation, with higher infiltration of inflammatory cells and expression of inflammatory cytokines in the ischemic brain. More accumulation of Th17 cells and IL-17+ γδ T cells were observed in the ileum. And in Kaede transgenic mice after photoconversion. Migration of CD4+ T cells and γδ T cells from the ileum to the brain was observed after ischemic stroke in photoconverted Kaede transgenic mice. Furthermore, the worse stroke outcome was abolished in the IL-17A knockout mice. These findings suggest that periodontitis salivary microbiota increased IL-17A-producing immune cells in the gut, likely promoted the migration of these cells from the gut to the brain, and subsequently provoked neuroinflammation after ischemic stroke. These findings have revealed the role of periodontitis in ischemic stroke through the gut and provided new insights into the worse outcome of ischemic stroke coexisting with periodontitis in clinical trials.

Potential secondary metabolite analysis of soil Streptomyces sp. GMR22 and antibacterial assay on Porphyromonas gingivalis ATCC 33277

Infectious diseases caused by oral pathogenic bacteria are currently a serious problem due to the increasing incidence of antimicrobial resistance. Streptomyces sp. GMR22, a soil actinobacterium which has large-genome size. In previous studies, it was known to have antifungal, and antibiofilm activity on Candida albicans. However, its antibacterial activity on oral pathogenic bacterium, Porphyromonas gingivalis is not clear. This study aimed to identify potential active compound based on genome mining analysis and to evaluate the antibacterial activity of GMR22 extract on P. gingivalis ATCC 33277. Potential active compounds and biosynthesis gene clusters were analysis using antiSMASH version 5. Antibacterial activity assay was carried out by the microdilution method on P. gingivalis ATCC 33277. Based on genome mining analysis polyketide synthase (PKS), the Streptomyces sp. GMR22 is the abundant BGCs (35%) and has large-predicted compounds which have antibiotic-antibacterial activity (22.9%). On antibacterial assay, chloroform extract of GMR22 at 7.8 – 62.5 µg/mL has high antibacterial activity on P. gingivalis compared to other extracts. Soil Streptomyces sp. GMR22 bacterium has biotechnological potential to produce active compounds for antibacterial.

The impact of integrating oral health education into a microbiology curriculum for students of department of life science

Background/purposeGood oral health is important for general health of the body. This study aimed to evaluate an innovative design incorporating oral health education related to oral pathogenic bacteria into a microbiology laboratory curriculum for students of department of life science by evaluating the students’ perspectives on the oral health curriculum. Materials and methodsTwenty-six students who took the elective course entitled “Microbiology Laboratory” in the National Taiwan Normal University in 2022 were invited to fill out the questionnaire for a presurvey regarding their familiarity with basic oral health concepts, and a postsurvey in which the students answered the same presurvey questions after finishing the class. ResultsOf the 26 students, 25 (96.15%) participated in both the presurvey and postsurvey. The results showed that the learning unit of oral health education related to oral pathogenic bacteria helped students in raising their concepts of oral health. To the questions asking that I understand the bacteria that cause dental caries and the pathogenic mechanism and I understand the bacteria that cause periodontal diseases and the pathogenic mechanism, the numbers of students who agreed both questions increased from 2 (8%) to 25 (100%), respectively. Moreover, the mean scores increased from 2.64 to 4.32 (P < 0.001) and from 2.68 to 4.32 (P < 0.001) for the two corresponding questions, respectively. ConclusionThe learning unit of oral health education in the microbiology laboratory curriculum helped the students of department of life science to increase their awareness and understanding of oral health.

Identification and Characterization of the Biosynthetic Pathway of the Sulfonolipid Capnine.

Capnine (2-amino-3-hydroxy-15-methylhexadecane-1-sulfonate) and capnoids (N-fatty acylated capnine derivatives) are sulfonolipids present in the outer membrane of gliding bacteria in the phylum Bacteroidetes and play a role in their unique gliding motility. They are structurally similar to sphingolipids and are thought to be biosynthesized via a similar pathway. Here we report the identification and biochemical characterization of the capnine biosynthetic enzymes cysteate synthase (CapA) and cysteate-C-fatty acyltransferase (CapB) from the pathogenic gliding bacterium Capnocytophaga ochracea and NAD(P)H-dependent dehydrocapnine reductase CapC from the avian pathogen Ornithobacterium rhinotracheale. CapA catalyzes the formation of cysteate from O-phospho-l-serine and sulfite, and CapB catalyzes the formation of dehydrocapnine from cysteate and 13-methyl-myristoyl-CoA, followed by reduction by CapC. CapA is closely related to cystathionine-β-synthase but distantly related to the archaeal cysteate synthase. Close homologues of CapA, CapB, and the CapA isozyme archaeal cysteate synthase are present in many Bacteroidetes bacteria, including environmental, pathogenic, and human oral and intestinal microbiome bacteria, suggesting the widespread ability of these bacteria to biosynthesize capnine and related sulfonolipids.

Inhibitory effects of a water-soluble jujube polysaccharide against biofilm-forming oral pathogenic bacteria

Oral diseases caused by infectious pathogens raises significant concerns in public health. In the light of side effects of current antibiotics therapy and growing drug resistance of pathogenic bacteria, natural products have become attractive alternatives for antibiotics agents in dental practice. This current study investigated the effects of polysaccharides extracted from Zizyphus jujuba Mill. on three major oral biofilm-forming pathogenic bacteria including caries-inducing Streptococcus mutans, lesions-causing MRSA, and periodontitis-related Porphyromonas gingivalis, as well as general oral microbiota. Our results demonstrated that jujube polysaccharide prepared in this study was mainly composed by galacturonic acid with an average molecular weight 242 kDa, which were further characterized for structural features by FT-IR spectra and NMR spectroscopy analysis. This jujube polysaccharide was shown to exhibit remarkable inhibitory effects against all the tested oral bacterial pathogens through various mechanisms including growth inhibition, biofilm prevention and disruption, intervention of bacterial infection (adhesion and invasion), attenuation of cytotoxicity, modulation of excessive inflammatory response of LPS-stimulated and MRSA-infected macrophages as well as positive regulation of oral microbiota. The present study paves the way to explore jujube polysaccharides for the prevention and treatment of oral infectious diseases.Graphic Abstract.

The Antibacterial Analysis of Alcohol-Free and Alcohol-Based Chlorhexidine Mouthwashes Against Oral Bacteria

Background: Chlorhexidine (CHX) is the gold standard chemical agent against oral pathogenic bacteria and is widely used for plaque/gingivitis control. The aim of the present study was to compare the effect of alcohol-based and alcohol-free CHX mouthwashes on oral microorganisms. Methods: In the present in vitro study, the standard strains of four microorganisms present in the oral cavity were prepared, including Streptococcus mutans, Streptococcus sanguinis, Streptococcus salivarius, and Lactobacillus casei. The serial dilutions of CHX antimicrobial agents were obtained, and the level of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was determined using the broth dilution method. Finally, data were analyzed using the Kruskal-Wallis test, the Mann-Whitney U test, and SPSS-16. Results: The MIC values of 0.12% and 0.2% alcohol-free CHX and 0.2% alcohol-based CHX for S. mutans were 1.17, 0.48, and 0.24 µg/mL, respectively. The MBC values of 0.12% and 0.2% alcohol-free CHX and 0.2% alcohol-based CHX for S. mutans were 18.78, 7.81, and 7.81 µg/mL, respectively. The MIC and MBC values of the tested CHX mouthwashes for S. mutans were significant (P≤0.05). Conclusions: Overall, the 0.2% alcohol-based CHX mouthwash had the highest antibacterial activity against gram-positive bacteria.

Incorporation of Plant Extracted Hydroxyapatite and Chitosan Nanoparticles on the Surface of Orthodontic Micro-Implants: An In-Vitro Antibacterial Study.

In our study, the structural and morphological applications of hydroxyapatite and chitosan nanoparticles and coated micro-implants were assessed for their ability to combat oral pathogenic bacteria. The hydroxyapatite, as well as chitosan nanoparticles, were synthesized from the Salvadora persica plant. The crystal morphology, phase composition, particle size, and surface functional groups of the nano-samples were analyzed via classical examinations and energy dispersive X-ray analysis. The prepared nanoparticles have been examined for antibacterial activity against four common oral bacterial strains. The antimicrobial effect was also assessed by the Live/Dead BacLight technique in combination with confocal scanning laser microscopy. Titanium micro-implants were coated with regular hydroxyapatite (HAP) and chitosan nanoparticles, and the surface was characterized by scanning electron microscopy. The analysis asserted elemental composition of the prepared nanoparticles and their textural features, metal crystallization, and functional bonds. The antibacterial activity of the nanoparticles was evaluated against oral pathogenic microorganisms by the disc diffusion method, minimum bacterial concentration (MBC), and minimum inhibitory concentration (MIC). Chitosan nanoparticles showed (MICs) of 8 μg mL−1 for (Streptococcus salivarius, Streptococcus mutans and Enterococcus faecalis), and 16 μg mL−1 for Streptococcus sanguinis. HAP nanoparticles showed (MICs) of 16 μg/mL for E. faecalis, and S. sanguis, 8 μg/mL for S. salivarius and finally 4 μg/mL for S. mutans. HAP nanoparticles showed enhanced antibacterial activity and more obvious damage in the bacterial cell membrane than that of synthesized chitosan nanoparticles. The prepared nanoparticles could successfully coat titanium microplates to enhance their efficiency.

Formulation and Antibacterial Potential of Sarang Semut (Myrmecodia pendans) against Oral Pathogenic Bacteria: An In Vitro Study

Background:Dental diseases are generally caused by oral bacteria such asEnterococcus faecalis,Streptococcus mutans, andStreptococcus sanguinis. These bacteria have resistance to synthetic drugs; thus, it is required to discover new antibacterial agents. Sarang Semut (Myrmecodia pendans) has been empirically used as a medicinal plant to treat various conditions, including those caused by pathogenic bacteria.Objective:The present study was aimed to investigate the antibacterial activity of Sarang Semut extracts againstE. faecalis,S. mutans, andS. sanguinis.Materials and Methods:Sarang Semut was extracted with several solvents to yieldn-hexane, ethyl acetate, methanol, and water extracts. Each extract and combination were adjusted for assay with chlorhexidine, fosfomycin, and quercetin and used as positive controls.Results:Then-hexane extract showed activity with inhibition zone values of 7.15 and 10.45 ppm againstE. faecalisandS. mutansat 1%, respectively. All combination extracts could inhibit the growth ofE. faecalisandS. sanguinis. The synergistic effects resulting from the combination of extract-fosfomycin were also presented in this evaluation, with the strongest shown by water-fosfomycin againstS. mutans, with inhibition zones of 28.5 mm at 1%.Conclusion:Sarang Semut extracts demonstrated antibacterial activity against oral pathogenic bacteria. These results offer alternative natural sources for the new antibacterial drug candidate.

Whey fermented by Enterococcus faecalis M157 exhibits antiinflammatory and antibiofilm activities against oral pathogenic bacteria

The aim of the present study was to investigate the antiinflammatory and antibiofilm effects of whey fermented by Enterococcus faecalis M157 (M157-W) against oral pathogenic bacteria. The M157-W significantly inhibited IL-1β, IL-6, and nitric oxide induced by the lipopolysaccharide of Porphyromonas gingivalis in RAW 264.7 cells. The M157-W also inhibited the production of IL-1β and IL-8 in human periodontal ligament cells. Treatment with M157-W suppressed the phosphorylation of mitogen-activated protein kinases as well as the activation of nuclear factor-κB in RAW 264.7 cells stimulated by P. gingivalis lipopolysaccharide. Furthermore, M157-W dose-dependently inhibited Streptococcus mutans biofilm, whereas unfermented whey did not inhibit the biofilm. Treatment with M157-W significantly suppressed gtfB, gtfC, and gtfD gene expression in S. mutans compared with the control (0 μg/mL), indicating that M157-W inhibits S. mutans biofilm formation by reducing the synthesis of extracellular polymeric substances. Collectively, these results suggest that M157-W has antiinflammatory and antibiofilm activities against oral pathogenic bacteria.