Bacteria Enterococcus Faecalis Research Articles

Biochemical and structural studies of two tetrameric nucleoside 2′-deoxyribosyltransferases from psychrophilic and mesophilic bacteria: Insights into cold-adaptation

Nucleoside 2′-deoxyribosyltransferases (NDTs) catalyze the cleavage of glycosidic bonds of 2′-deoxynucleosides and the following transfer of the 2′-deoxyribose moiety to acceptor nucleobases. Here, we report the crystal structures and biochemical properties of the first tetrameric NDTs: the type I NDT from the mesophilic bacterium Enterococcus faecalis V583 (EfPDT) and the type II NDT from the bacterium Desulfotalea psychrophila (DpNDT), the first psychrophilic NDT. This novel structural and biochemical data permitted an exhaustive comparative analysis aimed to shed light into the basis of the high global stability of the psychrophilic DpNDT, which has a higher melting temperature than EfPDT (58.5 °C versus 54.4 °C) or other mesophilic NDTs. DpNDT possesses a combination of unusual structural motifs not present neither in EfPDT nor any other NDT that most probably contribute to its global stability, in particular, a large aliphatic isoleucine-leucine-valine (ILV) bundle accompanied by a vicinal disulfide bridge and also an intersubunit disulfide bridge, the first described for an NDT. The functional and structural features of DpNDT do not fit the standard features of psychrophilic enzymes, which lead us to consider the implication of (sub)cellular levels together with the protein level in the adaptation of enzymatic activity to low temperatures.

Phosphate Ions Alter the Binding of Daptomycin to Living Bacterial Cell Surfaces.

Advancements in antibiotic drug design are often hindered by missing information on how these small molecules interact with living cells. The antibiotic, daptomycin, has found clinical success and an emerging resistance, but a comprehensive picture of its mechanism of action has remained elusive. Using a surface-specific spectroscopy technique, second harmonic generation, we are able to quantitatively assess the binding of daptomycin to living cell membranes without the addition of exogenous labels. Our results reveal similar binding affinities for both Gram-positive and Gram-negative bacteria studied, including Escherichia coli. More importantly, we show that the presence of phosphate ions influences the binding of daptomycin to the Gram-positive bacterium Enterococcus faecalis. The role of environmental phosphate has not previously been considered in any proposed mechanism, and its implications are expected to be important in vivo.

ANTIBACTERIAL EFFECTIVENESS OF LERAK FRUIT ETHANOL EXTRACT (Sapindus rarak DC) AND 2% CHLORHEXIDINE IN Enterococcus faecalis

The failure of a root canal treatment can be caused by the facultative anaerobic bacteria Enterococcus faecalis, which should be eliminated throughout root canal irrigation. Chlorhexidine 2% is a popular antibacterial liquid used in root canal irrigation. Natural substances can also be used to make antibacterial irrigation liquids. One natural substance with antibacterial properties is lerak fruit extract (Sapindus rarak DC), containing 28 per cent of saponins, alkaloid compounds, polyphenols, antioxidant chemicals, and flavonoid groups and tannins. This study was conducted to determine the effectiveness of 25% lerak fruit extract (Sapindus rarak DC) against E. faecalis compared to 2% Chlorhexidine. This study is a pure experimental study using the agar diffusion method against three experimental groups chlorhexidine 2% as a positive control, lerak fruit extract (Sapindus rarak DC) as a treatment group, and aquadest as a negative control. Each group was repeated ten times on Muller Hinton Agar (MHA) media which was applied using a paper disc. Then the diameter of the inhibition zone was calculated using a caliper. The results in this study, 25% lerak (Sapindus rarak DC) fruit extract had an average inhibition zone diameter of 11.775 mm, and an average inhibition zone diameter of 2% chlorhexidine was 19.745 mm. The difference in the diameter of the inhibition zone was significantly different in all groups. Conclusion ethanol extract of lerak fruit (Sapindus rarak DC) 25% can inhibit the growth of E. faecalis and can be used as an alternative to other antimicrobial agents as disinfection of root canal irrigation.

A binuclear copper(II) complex based on hydrazone ligand: Characterization, molecular docking, and theoretical and antimicrobial investigation

AbstractA new binuclear copper(II) complex [Cu2L2(μ‐SO4)(dmf)] with the 2‐acetylpyridinebenzoylhydrazone (HL) ligand was synthesized and characterized by elemental analysis, Fourier transform infrared (FT‐IR), ultraviolet–visible (UV–Vis), single‐crystal X‐ray diffraction, density functional theory (DFT), and molecular docking studies. The crystal structure revealed each copper(II) atom coordinated to the NNO chelating system of the anionic hydrazone ligand and a sulfate bridged. The copper ions are connected by a sulfate bridge, which keeps a distance of 3.292(3) Å between the two copper(II) centers. Additionally, only one of the copper(II) atoms is coordinated to the oxygen atom of the N,N‐dimethylformamide (dmf) solvent molecule, resulting in two different geometry to each metal center. Cu···O interactions are observed for the secondary coordination sphere of Cu1 and Cu2 atoms with distances of 2.545(2) and 2.821(3) Å, respectively. Theoretical studies with DFT were performed to optimize the geometry of the complex and investigate its spectroscopic properties supporting the experimental results. Two different approaches were used in computational calculations, the plane wave using Perdew–Burke–Ernzerhof (PBE) functional and the localized basis set using the following functionals: B3LYP, B3PW91, CAM‐B3LYP, LC‐wPBE, M06‐2X, ωB97‐XD, PBE1PBE, and HSEH1PBE. The in vitro antibacterial potential of the new complex was evaluated against pathogenic bacteria and fungi and compared with the free ligand. The molecular docking was used to predict the inhibitory activity of the ligand and complex against one Gram‐positive bacteria (Enterococcus faecalis), one Gram‐negative bacteria (Enterobacter aerogenes), and one fungi (Candida albicans) species.

Determination of Bioactive Properties of Alcohol Extracts of Types of Pleurotus sajor-caju and Pleurotus ostreatus

In this study, alcohol extracts of Pleurotus sajor-caju and Pleurotus ostreatus which are edible mushroom species were obtained and their extract contents were determined by GC-MS. Antioxidant content of these alcohol extracts were determined with 2-2-diphenyl, 1-picrylhydrazyl (DPPH). Antimicrobial activity of alcohol extracts were determined on Klebsiella oxycota, Pseudomonas aeruginosa, Staphylococcus aureus, Corynobacterium diphtheria, Enterococcus faecalis, Escherichia coli, Serratia marcescens, Bacillus cereus and Bacillus thuringiensis bacteria, and Rhodotorula glutinis and Candida albicans yeasts. Moreover, this study indicated the anti-quorum sensing activity of the tested mushroom extracts against Chromobacterium violaceum CV026. P. sajor-caju and P. ostreatus alcohol extract compositions were determined with GC-MS. According to GC-MS results, 20 different compounds were found in P. sajor-caju and P. ostreatus alcohol extract. Hexadeconoic acid, linoleic acid, octadecanolacid,2,3-dihydroxypropyl ester and palmitic acid were found in both mushroom extracts. Because they contain a high content of fatty acids, alcohols, aldehydes, ketones and terpenoids, these extracts can be used both as antimicrobial, anticancerogenic, antioxidant and antiaging agents or can be consumed as a food supplements.

The inhibition of leaf extract Moringaoleifera on the formation biofilm bacteria Enterococcus faecalis

Background: Enterococcus faecalisis the most common bacteria that cause failure to root canal treatment, which can become very resistant under biofilms. Moringaoleifera has antibacterial properties and may affect the multidrug-resistant bacteria. Purpose: This study aimed to observe the inhibition of Moringaoleifera leaf extract on the biofilm formation of bacteria Enterococcus faecalis. Method: This study was true experimental laboratory research with post-test only control group design and tested using biofilm method, divided into six groups, each group consisted of eight samples. The control groups were: K- (CMC 0,1%), K+ (ChKM), and four treatment groups were: P1 (Moringaoleifera 20%), P2 (Moringaoleifera 40%), P3 (Moringaoleifera 60%), P4 (Moringaoleifera 80%). Antibacterial inhibition was determined by the value of Optical Density in the ELISA Reader. Data analysis using Kruskal-wallis followed by Mann-Whitney test. Results: There were significant differences (p <0.05) seen from the percentage value of biofilm inhibition, on the K - (0 %) group compared with K+ (47,69%), P1(7,68%), P2 (21,13%), P3 (42,33%) and P4 (55,78%), as well on K + group (ChKM) compared with P4 group (Moringaoleifera 80%). Conclusion: Moringaoleiferaleaf extract has inhibition effect for the formation of bacteria Enterococcus faecalis biofilm and the effect is 80% greater than ChKM.

Application of impedance measurement to investigate in vitro inhalation toxicity of bacteria

BackgroundWorkers of agriculture and intensive life stock farming are exposed to highly contaminated workplaces. Bioaerosol exposures are suspected to trigger respiratory health effects of the workers. So far, risk evaluation of bioaerosols has been assessed through the infectivity of comprising biological agents that is classified in Europe by four risk groups according to the criteria of Directive 2000/54EC of the European Parliament. However, this directive additionally requires the risk assessment of allergenic and toxigenic effects without further elaboration. The aim of our study was to establish an in vitro screening system that is able to measure inhalative toxic effects of bacteria and their metabolites.MethodsIn this study, we analyzed three bacterial toxins and five culture supernatants of selected bacteria with known toxicity as model agents exposed to the lung epithelial cell line NuLi-1. We used electrical cell-substrate impedance sensing (ECIS) method to monitor real-time cell changes and the viability test Prestoblue™.ResultsWe confirmed concentration dependent cytotoxic effects of the selected toxins in NuLi-1 cells over a period of up to 48 h. Each toxin resulted in a different but specific impedance profile over time according to their mode of action, whereas viability assay showed the metabolic activity of the cells at a chosen time point without revealing any information on their mode of action. Furthermore, dose-response-relationships were monitored. Tested model bacteria (Streptoccous pneumoniae, Acinetobacter radioresistens, Aerococcus viridans, Aeromonas hydrophila) reacted according to their expected toxicity except one bacterium (Enterococcus faecalis). The established assays revealed the concentration dependent onset and intensity of bacterial cytotoxicity and the viability of the cells at 24 h and 48 h exposure.ConclusionImpedance measurement and the viability assay Prestoblue™ in combination are suitable as sensitive screening methods to analyze toxic potential of bacteria and can therefor support the risk assessment of workplaces in terms of the directive 2000/54/EC.

Biofilm Effectivity of Ethanol Extracts (Casuarina equisetifolia) Leaves of the Bacteria Enterococcus faecalis

Background: Enterococcus faecalis is one of the bacteria that can form biofilms that can cause persistent endodontic infections. Biofilm is the unity of microbial cell surface surrounded by a matrix of extracellular polymeric substances (EPS). The ethanol extracts of Casuarina equisetifolia leaves are known to have potentially bioactive compounds as antibacterials such as flavonoids, saponins, tannins, phenols, and alkaloids. Objective: To determine the power antibiofilm ethanol extracts of Casuarina equisetifolia leaves at multiple concentrations of the bacteria Enterococcus faecalis. Methods: This study is an experimental research design post-test only control group design. The sample divided into 5 groups consisted of positive control Enterococcus faecalis in media Trypticase Soy Broth (TSB)+DMSO 1%, and 4 treatment groups of ethanol extracts of Casuarina equisetifolia leaves a concentration of 0,5%, 1%, 1,5%, and 2%. Biofilm is made using Enterococcus faecalis ATCC 29212 bacteria were cultured on TSB media were incubated for 1x24 hours. 0,1 ml of the bacteria Enterococcus faecalis with a concentration of 106 put on a plate micro titter then done using crystal violet staining. Biofilm-checked by measuring optical density (OD) values ​​using the ELISA reader. Data analysis used Kruskal-Wallis followed by Mann-Whitney test. Results: The ethanol extracts Casuarina equisetifolia leaves on the growth of Enterococcus faecalis bacteria indicate the presence of power antibiofilm. The results mean % mortality of bacteria (p<0.05) were significant in all groups that have the power antibiofilm effectiveness as against the growth of bacteria Enterococcus faecalis. Conclusion: The ethanol extracts Casuarina equisetifolia leave have antibiofilm power against bacterial growth Enterococcus faecalis.

Investigation on biofilm formation activity of Enterococcus faecium under various physiological conditions and possible application in bioremediation of tannery effluent

Treatment of tannery effluent (TE) using bacterial biofilm is a trending approach in the current scenario, due to greater survival and adaptation in stress conditions. The present study is concerned with the characterization of biofilm-forming bacterium Enterococcus faecium from tannery sludge and the investigation of their activity under different physiological conditions. Biofilm formation by E. faecium was strongly affected by variable physiological conditions. The optimum conditions were pH 7.5, temperature 28 °C, incubation time up to 96 h, glucose 1%, yeast extract 0.1–0.5%, NaCl 0.1–0.5%, tannery effluent-TE up to 50% v/v and Cd, Cr (VI) and Ni from 0.25 to 0.5 mM. Further, E. faecium treated TE was less phytotoxic on the fenugreek plant than the TE treated by non-biofilm forming isolate. The toxicity of TE could be reduced by the potentially biofilm-forming bacteria, which may be used in the bioremediation process.

Controlling the movements of E. faecalis bacteria that carry a negative electric charge with an electric field

One of the main problems of bacteria sensors is that sufficient numbers of bacteria cannot approach and attach to the sensor surface. In this study, it has been suggested that an external electrical field can be applied to bacterial sensors to eliminate this problem. Moving Enterococcus faecalis (E. faecalis) bacteria, which carry a negative electric charge, in a desired direction with the effect of an electric field is an example of this. The Ag/PS/Si/In structures used as the sensor platform in the experiments were produced on n-type single crystal silicon by electrochemical etching method with 50% porosity and 1–5 μm pore size. Bacterial approach and removal experiments were carried out by immersing this PS-based structure in fluids containing E. faecalis bacteria and applying an electric field of 0–5 kV/cm in forward and reverse directions. Physical properties of the Ag/PS/Si/In structure were examined by immersing them in fluids containing live and dead E. faecalis bacteria and applying a fixed 7 kV/cm electric field value for 0–3 h. All experimental results were analyzed by impedance spectroscopy technique.

Development and characterization of antimicrobial and antioxidant whey protein-based films functionalized with Pecan (Carya illinoinensis) nut shell extract

Aim of this study was the development of an active packaging based on whey proteins (WP) functionalized with Pecan nut shell extract (PNSE). To this purpose, aqueous solutions of WP, PNSE and glycerol were mixed and characterized, whereas corresponding films were prepared by casting. Zeta-potential measurement revealed that the film forming solutions were stable, and the particle size was reduced further to the incorporation of PNSE, as a result of tannins-WP interactions. Films were handleable and homogeneous, and PNSE was able to improve their mechanical and barrier properties. PNSE-containing films inhibited the growth of the foodborne bacteria Enterococcus faecalis and Salmonella enterica subsp. enterica ser. Typhimurium. Ferric reducing/antioxidant power assay clearly highlighted the ability of PNSE to impart antioxidant properties to the films. Finally, simulated digestion experiments showed a significant lowering of the proteolysis rate in the presence of PNSE, although 40 % of the protein was still digested after 60 min incubation. Overall, these results put the basis for a possible use of PNSE functionalized WP-based films as new environmentally friendly candidates for increasing the shelf-life of foods.

Characteristics of High-Level Aminoglycoside-Resistant Enterococcus faecalis Isolated from Bulk Tank Milk in Korea.

Simple SummaryAminoglycosides are used to treat various infections in veterinary and human medicine. However, with the emergence of high-level aminoglycoside resistance in human and food-producing animals, the synergism of aminoglycosides with beta-lactam or glycopeptide is being threatened. Moreover, the environmental mastitis-causing agent, enterococci, has emerged as a cause of nosocomial infection due to its antimicrobial resistance. Therefore, the purpose of this study was to investigate the characteristics of high-level aminoglycoside-resistant Enterococcus faecalis isolated from bulk tank milk in Korea. It showed that 185 (61.5%) isolates out of 301 were high-level aminoglycoside resistant, while 149 isolates were multidrug resistant.Enterococci, which are considered environmental mastitis-causing pathogens, have easily acquired aminoglycoside-resistant genes that encode various aminoglycoside-modifying enzymes (AME). Therefore, this study was conducted to compare the distribution of high-level aminoglycoside-resistant (HLAR) and multidrug-resistant (MDR) Enterococcus faecalis (E. faecalis) bacteria isolated from bulk tank milk in four dairy companies in Korea. Moreover, it analyzed the characteristics of their antimicrobial resistance genes and virulence factors. Among the 301 E. faecalis bacteria studied, 185 (61.5%) showed HLAR with no significant differences among the dairy companies. Furthermore, 129 (69.7%) of the 185 HLAR E. faecalis showed MDR without significant differences among companies. In contrast, HLAR E. faecalis from companies A, B, and C were significantly higher in resistance to the four classes than those in company D, which had the highest MDR ability against the three antimicrobial classes (p < 0.05). In addition, in the distribution of AME genes, 72 (38.9%) and 36 (19.5%) of the isolates carried both aac(6′)Ie-aph(2″)-la and ant(6)-Ia genes, and the ant (6)-Ia gene alone, respectively, with significant differences among the companies (p < 0.05). In the distribution of virulence genes, the ace (99.5%), efa A (98.9%), and cad 1 (98.4%) genes were significantly prevalent (p < 0.05). Thus, our results support that an advanced management program by companies is required to minimize the dissemination of antimicrobial resistance and virulence factors.

Effect of Arabica Coffee Bean Extract (Coffea arabica) as a Growth Inhibitor of Enterococcus faecalis ATCC 29212

Arabica coffee seeds contain a composition of Caffeine, Chlorogenic acid, Flavonoids, and Trigonelline. The purpose of this study is to test the antibacterial of Arabica coffee seed extract against bacterium Enterococcus faecalis at concentrations of 1,5625%, 3,125%, 6,25%, 12,5%, 25%, 50% and 100%. The extraction method using maceration with solvent 96%. Antibacterial activity test was done by using the Kirby and Bauer diffusion test method. The results showed that Arabica coffee seed extract could provide inhibition starting from 3,125% with an average diameter of inhibition zone of 1,16 mm to the largest concentration of 100% with an average zone diameter of inhibition of 14,6 mm. At the same time, the average diameter of the inhibitory zone of antibiotic ampicillin at a concentration of 1% as a control (+) is 24,6 mm. The results showed that the greater concentration, the greater the inhibitory zones are formed.&#x0D; Keywords: Coffea arabica, Enterococcus faecalis, antibacterial, inhibition zone

The antimicrobial activity of polyfloral honey and its awareness among urban consumers in Slovakia

The current interdisciplinary research studies the antimicrobial activity of selected polyfloral kinds of honey (n = 30) against three microorganisms (gram-positive bacteria Enterococcus faecalis, gram-negative bacteria Salmonella enterica, and one yeast Candida krusei) as well as investigates consumer behavior and awareness towards honey healing properties. Consumer research involved 617 honey consumers living in urban areas. T-test for Equality of means, non-parametric tests, and descriptive statistics were applied. Results showed that antimicrobial activity was found in all honey samples with a concentration of 50%. Nevertheless, better activity was obtained in honey samples from urban beekeepers compared to samples from retail stores. Results of consumer research showed that honey is mostly used as food (sweetener in beverages, ingredient in the recipe, or direct consumption) and as medicine mainly during the winter period. The consumer awareness towards honey healing effects was very high (97%), however, 1/3 of respondents were not able to list any specific examples, and only 11 % mentioned antibacterial activity. Furthermore, more than 70% of respondents did not know to explain the term “medical honey” and more than 50% of respondents are not aware of the maximum temperature used for heating honey without decreasing its biologically active compounds.

Co-precipitation synthesis of cobalt doped ZnO nanoparticles: Characterization and their applications for biosensing and antibacterial studies

A new modified sensor based on carbon paste electrode (CPE) was developed using cobalt doped ZnO (Co-ZnO) nanoparticles (NPs). In this work, we demonstrated the analytical behavior and applications of CPE modified with Co-ZnO/MCPE for the simultaneous determination of uric acid (UA) and adrenaline (AD) with highly selective and sensitive using voltammetric techniques. The synthesized Co-ZnO NPs were characterized by utilizing XRD, FTIR, FESEM with EDX, TEM, UV–Vis and photoluminescence spectroscopy. XRD suggests that the average size of these NPs was between 21 and 35 nm with a hexagonal wurtzite structure. Tauc plot exhibited that the optical energy bandgap of ZnO NPs gradually decreases with Co doping. Compared with undoped ZnO, Co-ZnO modified carbon paste electrode (Co-ZnO/MCPE) exhibits excellent electrochemical performance towards the oxidation of UA. Influencing factors, including scan rate, concentration, and pH values were optimized. Under the optimal condition, the Co-ZnO/MCPE responded to UA linearly with a detection limit of 3.37 µM and the fabricated sensor exposes diffusion-controlled electrode process. The developed Co-ZnO/MCPC has capable of determination of both UA and AD simultaneously with two different oxidation peaks. The sensitivity, long-term stability and reproducibility of the developed sensor were estimated. The bacterial efficiency of undoped and Co-ZnO NPs was inspected against gram-negative (Escherichia coli) and gram-positive (Enterococcus faecalis) bacteria.

Effectiveness of Tamarillo Skin Extract (Solanum betaceum Cav.) with Sealer Combination in Inhibiting Growth of Enterococcus faecalis

Introduction : Caries is a growth medium for pathogenic micro-organisms an inflammatory process can occur which can cause damage to the tooth pulp. Enterococcus faecalis one of the Gram-positive facultative anaerobes which causes failure after endodontic treatment. In the field of dentistry, herbal ingredients can be used as alternative medicinal ingredients because the ingredients is tamarillo skin which contains flavonoids, terpenoids, saponins and phenol compounds. In addition to herbal alternatives, endodontic filling also uses ingredients that have antibacterial potential that can kill and prevent reproduction in the root canals, one of which is the zinc oxide eugenol sealer which is usually applied together with gutta percha. Research objective: to determine the effectiveness of the extract of tamarillo (Solanum betaccum Cav.) skin sealer combination in inhibiting the growth of Enterococcus faecalis. Method: The research was conducted in an experimental laboratory post test only control group design. Results : a sealer made from zinc oxide-eugenol had the largest diameter compared to the combination group of 100%, 75%, 50%, 25% tamarillo skin extract with sealer, and aquadest. Based on the One Way Anova test, there was a significant difference in the mean diameter of the inhibition zone (p &lt;0.05) and the Post Hoc LSD analysis test showed that the sealer was the best group to kill the Enterococcus faecalis bacteria. Conclusion : sealers have a good effect on inhibiting Enterococcus faecalis bacteria as a cause of failure in endodontic treatment.

Evolution of pathogen-specific improved survivorship post-infection in populations of Drosophila melanogaster adapted to larval crowding.

The environment experienced by individuals during their juvenile stages has an impact on their adult stages. In holometabolous insects like Drosophila melanogaster, most of the resource acquisition for adult stages happens during the larval stages. Larval-crowding is a stressful environment, which exposes the larvae to scarcity of food and accumulation of toxic waste. Since adult traits are contingent upon larval stages, in larval-crowding like conditions, adult traits are prone to get affected. While the effect of resource limited, poor-developmental environment on adult immune response has been widely studied, the effect of adaptation to resource-limited developmental environment has not been studied, therefore in this study we assayed the evolution of ability to survive infection in adult stages as a correlated response to adaptation to larval crowding environments. Using four populations of Drosophila melanogaster adapted to larval crowding for 240 generations and their respective control populations, we show that populations adapted to larval crowding show an improved and evolved post-infection survivorship against a gram-negative bacteria Pseudomonas entomophila. Whereas, against a gram-positive bacteria Enterococcus faecalis, no difference in post-infection survivorship was observed across control and selected populations. In this study, we report the co-related evolution of pathogen-specific increased survivorship post-infection in populations of Drosophila melanogaster as a result of adaptation to larval crowding environment.

Fabrication of different SnO2 nanorods for enhanced photocatalytic degradation and antibacterial activity.

The acid-mediated (oxalic acid [OXA], cinnamic acid [CA], and itaconic acid [IA]) SnO2 nanorods were synthesized by the hydrothermal method. The synthesized SnO2 nanorods, in turn, were analyzed with various physico-chemical techniques such as the X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), and Raman spectroscopy. Furthermore, the photocatalytic activity of the different SnO2 nanorods was investigated with the malachite green (MG) dye under visible light illumination. The OXA-SnO2 nanorods displayed an excellent degradation performance with observed value at 91% and it was compared to CA and IA-SnO2 nanomaterials. This tetragonal phase was identified and confirmed by XRD studies. In this regards, obtained band gap energy is low then optimally performed to the photocatalytic evolution. The OXA-SnO2 materials were tested for antibacterial and antifungal studies; this was as shown in good biological activities with admire to the different bacterial strains. The Candida albicans (antifungal) and Enterococcus faecalis (Gram-positive) bacteria were not affected in the microbial studies.

Efficacy of Cyombopogon Citratus Extract Against Enterococcus Faecalis

Endodontic treatment refers to the act of removing infected pulp tissue and formingand reforming the root canals to prevent bacteria from entering the root canals.Microbial infection in the root canal or in the periapical area is a factor that can leadto failure of root canal treatments. Endodontic treatment failure can be caused thebacteria Enterococcus faecalis. The irrigation agent commonly used is sodiumhypochlorite. Sodium hypochlorite in large concentrations can be toxic to tissues.Lemongrass plant (Cymbopogon citratus) is a natural ingredient that can be used asan antibacterial agent. The aims of study to determine the comparison of theantibacterial effectiveness of lemongrass plant extracts (Cyombopogon citratus (DC).Staph) concentrations of 25%, 50%, 75%, 100% with 2.5% sodium hypochlorite ininhibiting the growth of the bacterium Enterococcus faecalis. Lemongrass plantextracts Cyombopogon citratus (DC). Staph) made by maceration method andconverted into 25%, 50%, 75%, and 100%. The bacterial test method used the agardiffusion test (Kirby-Bauer test) to see the effectiveness of antibacterialsThe result ofthe one way ANOVA statistical test resulted in significance value of p=0,001 (p&lt;0,05)so that means there was differences in the average diameter of inhibitory lemongrassplant extracts (Cyombopogon citratus (DC). Staph) concentrations of 25%, 50%,75%, 100% with 2.5% sodium hypochlorite in inhibiting the growth of the bacteriumthe results are 13.68 ± 1.34 mm, 16.08 ± 0.87 mm, 16.33 ± 0.35 mm, 17.78 ± 0.93mm and 7.83 ± 0.44 mm and reinforced by the posthoc Tukey HSD test. Theconclusion from the study that there is a difference between the antibacterialeffectiveness of lemongrass plant extract (Cyombopogon citratus (DC). Staph)concentrations of 25%, 50%, 75% and 100% with 2.5% sodium hypochlorite ininhibiting the growth of the bacterium Enterococcus faecalis.

Antimicrobial Test of 1-(2.5-Dihydroxi Phenyl)-(3-Pyridine-2-Il) -Propanone Compound in Enterococcus Faecalis and Escherichia Coli Bacteria Using a Well Diffusion Method

1-(2.5-dihydroxy phenyl)-(3-pyridine-2-il)-propenone compound is a compound synthesized by reacting the pyridine-2-carbaldehyde and 2.5-dihydroxyacetophenone compound without solvent with K2CO3 (Potassium Carbonate) catalyst in the microwave. The 1-(2.5-dihydroxy phenyl)-(3-pyridine-2-il)-propenone compound is a chalcone derivative compound substituted by two hydroxy groups on ring A and has 2-pyridyl groups on ring B. Chalcone is a secondary metabolite compound from the flavonoid group, which has several activities as anti-platelet, anti-bacterial, immunomodulator, anti-hyperglycemic, and anti-inflammatory. This study aims to determine the antibacterial effect of 1-(2.5-dihydroxifenil)-(3-pyridine-2-il)-propenone compound against Enterococcus faecalis and Escherichia coli bacteria. This study used TLC (Thin Layer Chromatography) and Melting Point Test to analyze the purity of 1-(2.5-dihydroxy phenyl)-(3-pyridine-2-il)-propenone compound. Meanwhile, the test for antibacterial activity used a well diffusion method. Concentration variation for 1-(2.5-dihydroxifenyl)-(3-pyridine-2-il)-propenone compound as antibacterial in Escherichia coli were 0.25 mg/100 μl, 0.5 mg/200 μl, and 0.75 mg/300 μl. Meanwhile, the concentration variation for Enterococcus faecalis bacteria was 5%, 2.5%, 1.25% and was replicated three times. The results of the compound purity test using the melting point test and Thin Layer Chromatography (TCL) showed that the 1-(2.5-dihydroxy phenyl)-(3-pyridine-2-il)-propenone compound was pure. The results of the antibacterial activity test for 1-(2.5-dihydroxiphenyl)-(3-pyridine-2-il)-propenone compound showed no zone of inhibition at each test concentration. In conclusion, the 1-(2.5-dihydroxifenyl)-(3-pyridine-2-il)-propenone compound did not have an antibacterial effect on Enterococcus faecalis and Escherichia coli bacteria.