Antibacterial activity of salvia officinalis L. against periodontopathogens: An in vitro study.

Being aware of the remarkable antimicrobial potential of S. officinalis L., we aimed to evaluate the antimicrobial activity of the S. officinalis dichloromethane crude extract (SOD), dichloromethane-soluble fractions (SODH and SODD), SODD subfractions (SODD1 and SODD2), and pure substances (manool, salvigenin, and viridiflorol) against periodontopathogens. This bioassay-guided study comprises five antimicrobial tests-determination of the Minimum Inhibitory Concentration (MIC), determination of the Minimum Bactericidal Concentration (MBC), determination of the antibiofilm activity, construction of the Time-kill curve (determination of Bactericidal Kinetics), and determination of the Fractional Inhibitory Concentration Index-on six clinical bacterial isolates and three standard bacterial strains involved in periodontal disease. SOD has moderate activity against most of the tested bacteria, whereas SODD1, SODH1, SODH3, and manool afford the lowest results. The Porphyromonas gingivalis (ATTC and clinical isolate) biofilm is considerably resistant to all the samples. In association with chlorhexidine gluconate, only SODH1 exerts additive action against P. gingivalis (clinical isolate). Therefore, SODH1 and manool are promising antibacterial agents and may provide therapeutic solutions for periodontal infections.

Antifungal activity of plant-derived essential oils on Candida tropicalis planktonic and biofilms cells.

Dental prosthesis supports Candida species growth and may predispose the oral cavity to lesions. C. tropicalis has emerged as a colonizer of prosthesis and has shown resistance to clinically used antifungal agents, which has increased the search for new antifungals. This work describes the effectiveness of fifteen essential oils (EOs) against C. tropicalis The EOs were obtained by hydrodistillation and were chemically characterized by gas chromatography-mass spectrometry. The antifungal activities of the EOs were evaluated by the microdilution method and showed that Pelargonium graveolens (Geraniaceae) (PG-EO) was the most effective oil. Geraniol and linalool were the major constituents of PG-EO. The 2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide (XTT) assay showed that all the clinical C. tropicalis strains formed viable biofilms. Scanning electron microscopy examination of the biofilms revealed a complex architecture with basal layer of yeast cells and an upper layer of filamentous cells. Treatments with PG-EO, linalool, and geraniol significantly reduced the number of viable biofilm cells and inhibited biofilm formation after exposure for 48 h. PG-EO, geraniol, and linalool were not toxic to normal human lung fibroblasts (GM07492A) at the concentrations they were active against C. tropicalis Together, our results indicated that C. tropicalis is susceptible to treatment with PG-EO, geraniol, and linalool, which could become options to prevent or treat this infection.

Assessment of the antibacterial, antivirulence, and action mechanism of Copaifera pubiflora oleoresin and isolated compounds against oral bacteria.

The microorganisms that constitute the oral microbiome can cause oral diseases, including dental caries and endodontic infections. The use of natural products could help to overcome bacterial resistance to the antimicrobials that are currently employed in clinical therapy. This study assessed the antimicrobial activity of the Copaifera pubiflora oleoresin and of the compounds isolated from this resin against oral bacteria. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays provided values ranging from 6.25 to > 400 µg/mL for the C. pubiflora oleoresin and its isolated compounds. The fractional inhibitory concentration index (FICI) assay showed that the oleoresin and chlorhexidine did not act synergistically. All the tested bacterial strains formed biofilms. MICB50 determination revealed inhibitory action: values varied from 3.12-25 µg/mL for the oleoresin, and from 0.78 to 25 µg/mL for the ent-hardwickiic acid. Concerning biofilm eradication, the C. pubiflora oleoresin and hardwickiic acid eradicated 99.9 % of some bacterial biofilms. Acid resistance determination showed that S. mutans was resistant to acid in the presence of the oleoresin and ent-hardwickiic acid at pH 4.0, 4.5, and 5.0 at all the tested concentrations. Analysis of DNA/RNA and protein release by the cell membrane demonstrated that the oleoresin and hardwiickic acid damaged the bacterial membrane irreversibly, which affected membrane integrity. Therefore, the C. pubiflora oleoresin and ent-hardwickiic acid have potential antibacterial effect and can be used as new therapeutic alternatives to treat oral diseases such as dental caries and endodontic infections.

Assessment of the antibacterial, cytotoxic and mutagenic potential of the phenolic-rich hydroalcoholic extract from Copaifera trapezifolia Hayne leaves.

Copaifera trapezifolia Hayne occurs in the Atlantic Rainforest, which is considered one of the most important and endangered tropical forests on the planet. Although literature works have described many Copaifera spp., their biological activities remain little known. In the present study, we aimed to evaluate (1) the potential of the hydroalcoholic extract from C. trapezifolia leaves (CTE) to act against the causative agents of tooth decay and apical periodontitis and (2) the cytotoxicity and mutagenicity of CTE to ensure that it is safe for subsequent application. Concerning the tested bacteria, the MIC and the minimum bactericidal concentration of CTE varied between 100 and 400 µg ml-1. The time-kill assay conducted at a CTE concentration of 100 µg ml-1 evidenced bactericidal activity against Porphyromonas gingivalis (ATCC 33277) and Peptostreptococcus micros (clinical isolate) within 72 h. CTE at 200 µg ml-1 inhibited Porphyromonas gingivalis and Peptostreptococcus micros biofilm formation by at least 50 %. A combination of CTE with chlorhexidine dichlorohydrate did not prompt any synergistic effects. The colony-forming assay conducted on V79 cells showed that CTE was cytotoxic at concentrations above 156 µg ml-1. CTE exerted mutagenic effect on V79 cells, but the micronucleus test conducted on Swiss mice and the Ames test did not reveal any mutagenicity. Therefore, the use of standardized and safe extracts could be an important strategy to develop novel oral care products with antibacterial action. These extracts could also serve as a source of compounds for the discovery of new promising biomolecules.

Influencia de los tipos de anclaje de los filamentos en la retención de streptococcus mutans en cepillos dentales: estudio preliminar / Influence of the types of filaments anchoring in the retention of streptococcus mutans on toothbrushes: preliminary study

Este estudio evaluó la retención del S. mutans (ATCC 25175) en los cepillos dentales Oral B Complete® y Sensodyne Esmalte Care®, que poseen distintas características de fijación y anclaje de los filamentos en sus partes activas. Nueve cepillos dentales de cada marca comercial fueron esterilizados en autoclave y, a continuación, inoculados con S. mutans (ATCC 25175), previamente desarrollado en caldo Brain Heart Infusion (BHI). Los análisis de retención bacteriana se realizaron en los tempos de 04, 12 y 24 horas de incubación, a 37ºC y en microaerofilia, en triplicata. En esas etapas, los cepillos fueron lavados con agua esterilizada e introducidos en tubos Falcon con caldo BHI, del cual fueron preparadas diluciones decimales hasta 10-3 para las cuatro primeras horas, hasta 10-4 para 12 horas, y hasta 10-5 para 24 horas de incubación. Alícuotas de esas diluciones fueron sembradas en la superficie del Ágar BHI, siendo las placas incubadas en microaerofilia por 24h a 37ºC. Tras la incubación, fue realizado un recuento de las unidades formadoras de colonia por mL (UFC/mL) y el análisis estadístico (Tests de Tukey pareado, p?0,05). Fueron observadas diferencias estadísticamente significantes (p?0,05) entre lo tiempos de evaluación de 12 horas. Concluyese que el cepillo dental Oral B Complete® presentó, comparativamente a Sensodyne Esmalte Care®, mayor retención del S. mutans (ATCC 25175).

This work evaluated the retention of S. mutans ATCC 25175 in the Oral B Complete and Sensodyne Esmalte Care toothbrushes that have distinct characteristics of insertion and anchorage of the filaments in its active parts. Nine toothbrushes of each trademark were sterilized in autoclave and, following this procedure, inoculated with S. mutans ATCC 25175, previously developed in Brain Heart Infusion (BHI).The analyses of bacterial retention occurred in the times of 04, 12 and 24 hours after incubation, at 37ºC and in microaerophilic, in triplicate. In these stages, the toothbrushes were washed with sterilized water and enclosed in Falcon tubes with BHI broth, of which decimal dilutions up to 10-3 were made for the four first hours, up to 10-4 for 12 hours, and up to 10-5 for 24 hours of incubation. Aliquots of these dilutions were sown in the surface of agar BHI, and the Petri dishes were incubated in microaerophilic for 24 hours, in a temperature of 37ºC. After the incubation, the counting of the colony forming units and the statistical analysis (Tukey Test paired, p?0.05) were performed. Significant statistical differences were observed (p?0.05) between the times of evaluation of 12 hours. It was concluded that the Oral B Complete toothbrush presents, compared with Sensodyne Esmalte Care, greater retention of S. mutans ATCC 25175.