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This study aimed to determine the antifungal and antibiofilm activities of Agelas dispar on biofilm-producing Candida species. The methanolic extract of A. dispar was obtained and the fraction Ag2 showed inhibitory activity for all 13 Candida strains tested, in concentrations ranging from 2.5 to 0.15625 mg/mL. Antifungal activity of fungicidal nature was seen between 5.0 and 0.3125 mg/mL of extract against the strains. All the strains were classified as biofilm producers. The methanolic extract Ag2 was tested at concentrations of 2.5 and 1.25 mg/mL for antibiofilm activity against the biofilm formation and maturation in all the strains of the genus Candida. Treated and untreated biofilm samples were selected for visualization using scanning electron microscopy (SEM). SEM allowed the visualization of the quantitative decrease in the microbial community, alterations of structural morphology, and destruction of both the formation and maturation of biofilms, at the cellular level. The mechanism of action of this fraction is suggested to be at the plasma membrane and/or cell wall alteration level. Therefore, the use of the methanolic extract of A. dispar may be a promising antifungal and antibiofilm therapeutic strategy against different species of the genus Candida.

PURPOSE To evaluate the performance of fully (Celtra Duo, Dentsply Sirona) and partially (VITA Suprinity, VITA) crystallized zirconia-reinforced lithium silicate and partially sintered lithium disilicate (IPS e.max CAD, Ivoclar Vivadent) glass-ceramics submitted to polishing, glazing, or no surface treatment after aging. MATERIALS AND METHODS Specimens of each glass-ceramic were subjected to polishing with rubber cups (POL), glazing (GL), or control (C; no treatment) and afterwards aged with 18,000 thermal cycles (5°C to 55°C). The average roughness (Ra), 2D and 3D morphology, contact angle, multispecies biofilm formation (Streptococcus mutans and Candida albicans), and mechanical strength were evaluated by atomic force microscopy (AFM, n = 5), sessile-drop goniometry (n = 5), spectrophotometry (n = 5), and flexural strength test (n = 10), respectively. Data were analyzed using two-way analysis of variance and Tukey test (α = 5%). RESULTS POL promoted lower Ra than glazing, and Celtra Duo presented higher Ra than IPS e.max CAD (P < .05). Surfaces without polishing promoted higher Ra than the POL group (P < .001), greater contact angle (P < .001), and significant morphologic changes, regardless of the glass-ceramic. Irrespective of the treatment, the contact angle was higher in Celtra Duo, and regardless of the material, there was higher biofilm formation and lower flexural strength of unpolished compared to POL or GL ceramics. CONCLUSION Polishing with rubber cups promoted lower roughness and minor morphologic surface alterations, but biofilm formation and flexural strength were similar to the glazed surface. In general, Celtra Duo and VITA Suprinity showed similar behavior to IPS e.max CAD, which makes zirconia-reinforced lithium silicate glass-ceramics a good option for indirect restorations.

Objective(s): The essential oil (EO) extracted from Cinnamomum verum leaves has been used as an antimicrobial agent for centuries. But its antifungal and antibiofilm efficacy is still not clearly studied. The objective of this research was to evaluate the in vitro antifungal and antibiofilm efficacy of C. verum leaf EO against C. albicans, C. tropicalis, and C. dubliniensis and the toxicity of EO using an in vitro model. Materials and Methods: The effect of EO vapor was evaluated using a microatmosphere technique. CLSI microdilution assay was employed in determining the Minimum Inhibitory (MIC) and Fungicidal Concentrations (MFC). Killing time was determined using a standard protocol. The effect of EO on established biofilms was quantified and visualized using XTT and Scanning Electron Microscopy (SEM), respectively. Post-exposure intracellular changes were visualized using Transmission Electron Microscopy (TEM). The toxicological assessment was carried out with the Human Keratinocyte cell line. The chemical composition of EO was evaluated using Gas Chromatography-Mass Spectrometry (GC-MS). Results: All test strains were susceptible to cinnamon oil vapor. EO exhibited MIC value 1.0 mg/ml and MFC value 2.0 mg/ml against test strains. The killing time of cinnamon oil was 6 hr. Minimum Biofilm Inhibitory Concentration (MBIC50) for established biofilms was

Medicinal plants play a major role as an alternative therapeutic agents for various disease conditions including cardiac and hepatic diseases, microbial infections and non-communicable disease such as diabetes mellitus. With the excessive use of synthetic antimicrobial drugs, micro-organisms become more virulent and resistant to available antimicrobial therapeutic agents. Further majority (around 60%-80%) of human microbial infections are biofilm associated infections and various resistance mechanisms of biofilms make it more difficult to eradicate or treat biofilm infections using available antimicrobial therapeutics. Further, biofilm structure acts as a physical barrier and prevent penetration of antimicrobial agents towards the biofilm core. Currently, scientists pay their attention to invent novel effective antimicrobial agents with less side effects for these biofilm infections. Phytochemicals have identified as a potential alternative antimicrobial strategy in biofilm control and eradication. Cinnamomum verum is a native Sri Lankan medicinal plant that has been widely used as a culinary spice, exhibits many medicinal benefits especially activity against microbial infectious diseases. Essential oils extracted from leaf and bark of C. verum have been used as a safe and effective antimicrobial agents against various infections for centuries. This review analyses the available scientific literature evidences on appositeness of true cinnamon leaf essential oil as an alternative antimicrobial strategy to control microbial biofilm infections with medical importance.

BACKGROUND Essential oils (EO) extracted from Cinnamomum verum has been used as an antimicrobial agents for centuries. The effects of C. verum leaf oil against virulence of microorganisms is not well studied yet. OBJECTIVES This study evaluates the effect of C. verum leaf oil against three virulence factors of Candida albicans, C. tropicalis and C. dubliniensis and its in-vivo toxicity. METHODS Chemical composition of EO was determined using gas chromatography-mass spectrometry (GC-MS). Minimum inhibitory concentration (MIC) was determined using clinical and laboratory standards institute (CLSI) M27-A3 broth microdilution. Effect of EO on initial adhesion was quantified using XTT assay after allowing Candida cells to adhere to the polystyrene surface for 2 h. Biofilm formation of Candida in the presence of EO was quantified using XTT viability assay. Efficacy on reduction of germ tube formation was evaluated using standard protocol. Visualisation of biofilm formation and progression under the EO treatment were done using scanning electron microscope (SEM) and Time lapses microscope respectively. In-vivo toxicity of EO was determined using Galleria mellonella larvae. Chlorhexidine digluconate: positive control. RESULTS Eugenol was the main compound of EO. MIC was 1.0 mg/mL. 50% reduction in initial adhesion was achieved by C. albicans, C. tropicalis and C. dubliniensis with 1.0, > 2.0 and 0.34 mg/mL respectively. 0.5 and 1.0 mg/mL significantly inhibit the germ tube formation. MBIC50 for forming biofilms were ≤ 0.35 mg/mL. 1.0 mg/mL prevent biofilm progression of Candida. SEM images exhibited cell wall damages, cellular shrinkages and decreased hyphal formation. No lethal effect was noted with in-vivo experiment model at any concentration tested. CONCLUSION C. verum leaf oil acts against virulence factors of Candida and does not show any toxicity.

Medicinal plants have long been used as an alternative in the treatment of diseases, whether using extracts, essential oils and / or bioactive components. Thus, the use of medicinal plants, with popularly known effects for the treatment of infections, has gained prominence, in research related to extracts and essential oils of medicinal plants, in an attempt to discover and future application of new molecules with antimicrobial and / or effect coadjuvant molecules to antimicrobials on the market. Studies with species of Melaleuca spp., Demonstrate wide application of its essential oil, without treating skin infections, microbial infections, herpes, diseases associated with pathogenic microorganisms of the oral cavity. The emerging microbial resistance to the drugs currently available on the market, has been affected by both researchers and the general population, so that the research experimented with was conducted revealing a high synergistic potential between drugs and natural drugs, present in drugs. In view of the above, this study aimed to present, through a bibliographic survey, a use of medicinal plants in the face of microbial resistance, as well as medicinal therapy based on the use of essential oils from alternative tea tree, leucadendron tea tree and quinquenervia tea tree, already inclusion in the literature.

The use of plants as an alternative to medicinal treatments is an ancient practice. Studies on medicinal plants have become increasingly relevant, and ethnobotanical and ethno-pharmacological knowledge is considered essential for the development of new drugs. Several plants have been tested in order to find active biocomposites that can be used in the development of new drugs (Amjad et al., 2017), since microbial resistance has brought great problems in the treatment of infectious diseases and the development of new agents antimicrobial agents (Ayaz et al., 2019). Objective: The present study aimed to study the antimicrobial activity of Origanum vulgare essential oil and its isolated Carvacrol compound against Candida, Streptococcus and Staphylococcus microorganisms. Results: The essential oil of O. vulgare demonstrated inhibitory activity for the genus Candida, Streptococcus and for the strain of Staphylococcus aureus at concentrations between 0.5 and 0.125 mg / ml; while carvacrol varied in concentrations between 0.250 and 0.0625 mg / ml. The fungicidal and bactericidal activities expressed concentrations of 0.5 and 0.250 mg / ml for the essential oil and 0.250 to 0.125 mg / ml for the compound. Conclusion: Oreganum vulgare essential oil (OE) and isolated compound Carvacrol are biologically active in a dose dependent manner against the species tested in their planktonic form.

Medicinal plants are attractive sources in the search of bioactive compounds in the treatment of infectious diseases. Considering that the infectious agent often develops resistance to existing treatments rapidly, the searches for such compounds are a never-ending process. One such infection, caused by Candida spp. is candidiasis, which is a public health problem. Additionally, many strains have resistance to traditional therapies. Therefore, we tested the antifungal activity of four compounds present in Mentha spp. with promising antifungal precedents. We measured inhibition of growth by microdilution, disruption of biofilm viewed by electron microscopy, inhibition of germ tube formation by optical microscopy and toxicity on HaCaT cells. Tests showed that the compounds tested had antifungal activity with a minimum inhibitory concentration of 0.5 mg/mL, at least, 50% of biofilm inhibition in the 0.5 mg/mL concentration, an inhibition of polymorphism to 86% and the changes in the cell envelope of yeast (SEM) and cell viability above 50% among the Candida strains tested. Therefore, the compounds exhibit promising antifungal properties and provide a reasonable therapeutic window to be used in association with other traditional antimitotic. Key words: Carvone, menthone, menthofuran, pulegone, Candida spp., biofilm, cytotoxicity.