Rosuvastatin enhances alterations caused by Toxoplasma gondii in the duodenum of mice.

Infection by Toxoplasma gondii may compromise the intestinal histoarchitecture through the tissue reaction triggered by the parasite. Thus, this study evaluated whether treatment with rosuvastatin modifies duodenal changes caused by the chronic infection induced by cysts of T. gondii. For this, female Swiss mice were distributed into infected and treated group (ITG), infected group (IG), group treated with 40 mg/kg rosuvastatin (TG) and control group (CG). After 72 days of infection, the animals were euthanized, the duodenum was collected and processed for histopathological analysis. We observed an increase in immune cell infiltration in the IG, TG and ITG groups, with injury to the Brunner glands. The infection led to a reduction in collagen fibers and mast cells. Infected and treated animals showed an increase in collagen fibers, acidic mucin-producing goblet cells, intraepithelial lymphocytes and mast cells, in addition to the reduction of muscle, neutral mucin-producing and Paneth cells. While treatment with rosuvastatin alone led to increased muscle layer, proportion of neutral mucin-producing goblet cells, Paneth cells, and reduction of collagen fibers. These findings indicate that the infection and treatment caused changes in the homeostasis of the intestinal wall and treatment with rosuvastatin potentiated most parameters indicative of inflammation.

Human apoCIII transgenic mice with epicardial adipose tissue inflammation and PRESERVATION of the cardiac plexus.

Hypertriglyceridemia is a result of the increase in the serum levels of lipoproteins, which are responsible for the transport of triglycerides and can be caused by genetic and/or metabolic factors. Animal models which either express or lack genes related to changes in the lipoproteins profile are useful to understand lipid metabolism. Apolipoprotein CIII (apoCIII) is an important modulator of hepatic production and peripheral removal of triglycerides. Mice that overexpress the apoCIII gene become hypertriglyceridemic, showing high concentrations of free fatty acids in the blood. Since hypertriglyceridemia is related to atherosclerosis, and the latter refers to cardiac alterations, this study aimed at evaluating the morphological, morphometric and quantitative profiles of the cardiac plexus, as well as the morphometric and histopathological aspects of the epicardial adipose tissue in human apoCIII transgenic mice. Therefore, 8-12-month-old male C57BL/6 mice that overexpressed human apoCIII (CIII) and their respective controls were used. Our results showed that overexpression of human apoCIII did not modify morphological or quantitative parameters of cardiac plexus neurons; however, age increased both, the area and the number of such cells. Furthermore, there was a direct correlation of this dyslipidemia to the thickening of periganglionar type 1 collagens. On the other hand, this overexpression caused epicardial adipose tissue inflammation and an increase in the area of the adipocytes, thus, favoring the recruitment of inflammatory cells in this tissue. In conclusion, this overexpression is harmful since it is related to an increase in cardiac adiposity, as well as to a predisposition to an inflammatory environment in the epicardial fat and to the incidence of cardiovascular diseases.

Treatment with Lycopodium clavatum 200dH Intensifies Kidney and Liver Injury in Mice Infected with Toxoplasma gondii.

The effects of infection with Toxoplasma gondii vary from asymptomatic to the development of alterations in various organs (including the liver and kidneys) which may be irreversible, and lead to the death of the host. Whereas homeopathy is an alternative and effective method for treating various diseases, including those caused by protozoa, we questioned the effect of using Lycopodium clavatum in mice infected with T. gondii. One hundred male Swiss mice, 60 days old, were divided into four groups (n = 25/group): NIC (uninfected and untreated control), IC (infected and treated with un-dynamized 7% alcohol solution [vehicle]), G48 (infected and treated 48 h before infection and treated three more times; at 2, 4, and 6 days post-infection (dpi) with L. clavatum 200dH), and G72 (infected and treated for 3 consecutive days before infection with L. clavatum 200dH). In this study, physiological, histopathological, and immunological parameters were evaluated. The L. clavatum 200dH intensified renal damage in mice infected with T. gondii from 7 dpi, causing severe and progressive alterations during this period, such as various degrees of inflammation, edema, atrophy, and tubular cystic dilation, degenerated tubules with intra-cytoplasmic vacuoles and coalescing spots, severe vascular lesions, glomerulonephritis, and peri-glomerular congestion. In the G72 animals, which received L. clavatum 200dH, more severe cortex damage was observed (91.66-96.66%) as compared to the IC group (55-80%) and more renal corpuscle, and renal tubule injury was observed (80 ± 5 to 96.7% ± 2.89 of the total area) during all periods, as compared to the IC group (p < 0.05). Both groups presented high liver enzyme levels, and the highest values for AST were observable at 60 dpi. We observed significant increases of type I and III collagen, as well as high levels of TGF-ß1 in both organs of the treated animals, the main factor involved in fibrosis in areas damaged by the process. L. clavatum 200dH intensifies kidney and liver alterations in mice infected with T. gondii. Our results reinforce caution when indicating administration schemes and dosages for ultra-diluted drugs.

Toxoplasma gondii causes lipofuscinosis, collagenopathy and spleen and white pulp atrophy during the acute phase of infection.

In this study, we evaluated homeostatic and functional disorders of the spleen in mice inoculated with Toxoplasma gondii. The kinetics of megakaryocyte and leukocyte production, body and spleen mass and certain histopathological aspects were analyzed. There was increased (P < 0.05) the accumulation of lipofuscin in the red pulp of the spleen, in the periods of 30 and 60 dpi of the infection, that is, in the chronification stage of the disease and decrease of the white pulp area. In addition, we observed (from 7dpi) a quantitative and qualitative increase (P < 0.05) in the deposition of collagen fibers in the spleen of all infected mice. Since resolution of the inflammatory process resulted in pathophysiological changes, we can suggest that the T. gondii invaded and multiplied in the cells of the white and red pulps of the spleen. Although we did not find the parasite in the spleen, this hypothesis is supported by the presence of diffuse inflammatory infiltrate, which extended through the spleen parenchyma of all inoculated mice. Taken together, our results suggest that T. gondii causes severe homeostatic disorders that have altered spleen physiology, including diffuse parenchymal inflammation, lipofuscinosis in histiocytes, early aging, collagenopathy, systemic sclerosis and spleen and white pulp atrophy.

Antibacterial activity against cariogenic bacteria and cytotoxic and genotoxic potential of Anacardium occidentale L. and Anadenanthera macrocarpa (Benth.) Brenan extracts.

OBJECTIVES: The present study aimed to assess the antibacterial activity against bacteria with cariogenic relevance, toxic and genotoxic potential of the plants Anacardium occidentale L. and Anadenanthera macrocarpa (Benth.) Bernam. DESIGN: Using a microdilution technique, the extracts were submitted to minimum inhibitory concentration (MIC) testing against Streptococcus mitis (ATCC 903), Streptococcus mutans (ATCC 25175), Streptococcus oralis (ATCC 10557), Streptococcus salivarius (ATCC 7073), Streptococcus sanguinis (ATCC 15300) and Streptococcus sobrinus (ATCC 27609). The toxicity of the extracts was then verified against eukaryotic cells. Additionally, a micronucleus assay was performed to investigate the potential mutagenic effects of the extracts on rat erythrocytes. The Student's t-test, Bonferroni test, and one-way ANOVA followed by Tukey's tests were used for statistical analysis, at a significance level of 5%. RESULTS: While the A. occidentale extract was able to inhibit all of the tested strains, with S. mutans and S. mitis being the most susceptible to that extract́s action, the A. macrocarpa did not show antimicrobial activity. Interestingly, the hemolytic, oxidant and antioxidant activities were slightly observed for either extract, even at high concentrations (1000mg/mL). The micronucleus assay showed no significant changes in the cells exposed to the extracts. CONCLUSION: The A. occidentale extract has potential as an antimicrobial agent with low eukaryotic cell toxicity or mutagenic activity. The A. macrocarpa extract, although absent of antibacterial activity might as well be a safe and effective phytotherapeutic alternative.

Effects of associations of tannins from Anacardium occidentale and Anadenanthera colubrina with cephalosporin against bovine Staphylococcus aureus isolates / Efeitos da associação de taninos de Anacardium occidentale e Anadenanthera colubrina à cefalosporina sobre Staphylococcus aureus isolados de bovinos

The association of natural compounds isolated from medicinal plants with conventional antibiotics, both with similar mechanisms of action, have become a viable alternative strategy to overcome the problem of drug resistance. This study aimed to evaluate the in vitro antimicrobial activity of tannic substances present in the bark of Anacardium occidentale and Anadenanthera colubrina against samples of Staphylococcus aureus when in combination with cephalexin. These combinations were evaluated by determining the minimum inhibitory concentration (MIC). For this purpose, tannins and cephalexin were serially dissolved in distilled water at concentrations ranging from 0.976 mg/mL to 500 mg/mL and 2 mg/mL to 512 mg/mL, respectively. When combined, the compounds inhibited S. aureus growth forming halos ranging from 0.9 to 46 mm with an MIC of 7.8 mg/mL (tannins) and 4 µg/mL (cephalexin). The resulting effect of the combination of natural and synthetic substances with similar mechanisms of action presented better results than when tested alone. Thus, the conclusion is that both the tannins and cephalexin had their antimicrobial action enhanced when used in combination, enabling the use of lower concentrations while maintaining their antibacterial effect against strains of S. aureus.(AU)

A associação de compostos naturais, isolados de plantas medicinais, com antibióticos convencionais, com mecanismos de ação semelhantes, torna-se uma estratégia alternativa e viável para superar o problema da resistência. Assim, nosso objetivo foi avaliar a atividade antimicrobiana in vitro de substâncias tânicas presentes na casca de Anacardium occidentale e Anadenanthera colubrina associadas à cefalexina, sobre amostras de Staphylococcus aureus. Avaliamos essa associação por meio da determinação da concentração mínima inibitória. Dessa forma, taninos e a cefalexina foram dissolvidos de forma seriada em água destilada em concentrações variando de 0,976 mg/mL a 500 mg/mL e 2 µg/mL a 512 µg/mL, respectivamente. Quando associados, inibiram o crescimento de S. aureus formando halos que variaram de 0,9 a 46 mm com concentração mínima inibitória de 7,8 mg/mL (taninos)/ 4 µg/mL (cefalexina). O efeito resultante da associação de substâncias, natural e sintética, com mecanismos de ação semelhantes, apresentou resultados superiores aos observados quando testados isoladamente. Podemos concluir que os taninos e a cefalexina tiveram sua ação antimicrobiana potencializada quando utilizados em associação, permitindo o uso de uma menor concentração, mantendo seu efeito antibacteriano sobre cepas de S. aureus.(AU)

Histopathological lesions in encephalon and heart of mice infected with Toxoplasma gondii increase after Lycopodium clavatum 200dH treatment.

In many cases, symptoms of toxoplasmosis are mistaken for the ones of other infectious diseases. Clinical signs are rare in immunocompetent people. However, when they arise, in the acute phase of infection, several organs are affected due to the rapid spread of tachyzoites through the bloodstream. In the present study, the reduction of tachyzoites in peripheral blood of mice of G72 (infected 72h after treatment) and G48 (infected 48h after treatment and treated three more times), when compared with IC (infected and non-treated), suggests protective effect exerted by Lycopodium clavatum. If on the one hand L. clavatum brought benefits, reducing parasitemia, on the other hand, the parasitism became exacerbated. Histopathological analysis demonstrated focal, multifocal and diffuse inflammatory infiltrates, ranging from absent, discreet, moderate to intense, in heart and encephalon of mice of NIC (non-infected and non-treated), IC, G48 and G72 groups, respectively. In the perivascular region and meninges, the injuries were enlarged. The presence of tachyzoites was demonstrated through immunohistochemical (IHC) assay in myocardium. Toxoplasma gondii induced increase of collagen fibers in myocardium of mice of G72 and G48 groups, compared with IC (p<0.05) and NIC (p<0.001). The presence of inflammatory infiltrates, as well as the progressive fibrosis, caused myocardial remodeling in animals treated with L. clavatum. Counterstaining with H&E suggests TGF-ß expression by mononuclear cells in the inflammatory infiltrate. Based on our results, we can conclude that the adopted regimen and potency exerted a protective effect, reducing parasitemia. However, it intensified the histopathological lesions in encephalon and heart of mice infected with T. gondii.

Antimicrobial and Anti-Adherent in vitro Activity of Tannins Isolated from Anacardium occidentale Linn. (Cashew) on Dental Biolfilm Bacteria

Objective:To evaluate the antimicrobial and ant-adherent in vitro activity of tannins isolated from Anacardium occidentale Linn. (Cashew) on dental biofilm bacteria. Material and Methods:Streptococcus mutans ATCC 25175, Streptococcus mitis ATCC 903, Streptococcus sanguis ATCC 15300, Streptococcus oralis ATCC 10557, Streptococcus salivarius ATCC 7073 and Lactobacillus casei ATCC 9595 samples were used in this study. The tests were performed by the solid medium dilution method to determine the Minimum Inhibitory Concentration (MIC). The Minimum Inhibitory Concentration of Adherence (MICA) of bacteria to glass was determined in the presence of 5% sucrose. As a positive control, 0.12% chlorhexidine gluconate was used. The substances were tested at concentrations of 1:1 (pure solution) up to 1:512. Data were analyzed using descriptive statistics and the SPSS software,version 15.0. Results:Tannins isolated from Anacardium occidentale Linn. (cashew) formed inhibition halos ranging from 11 to 17 mm in diameter and were capable of inhibiting the growth of bacteria tested at concentrations of 1:4 (S mutans), 1:16 (S mitis), 1:8 (Ssanguis), 1:4 (S oralis), 1:8 (S salivarius) and 1:2 (L casei). The tannin solution was effective in inhibiting the adherence of microorganisms to glass, and its effect on Streptococcus sanguis (1:512) and Lactobacillus casei (1:512) stood out, showing ant-adherent effect at all concentrations tested. Conclusion:Tannin isolates produced in vitro antimicrobial and ant-adherent activity on dental biofilm-forming bacteria and can be considered as an alternative treatment in infectious processes in clinical dentistry

Melittin induces in vitro death of Leishmania (Leishmania) infantum by triggering the cellular innate immune response.

BACKGROUND: Apis mellifera venom, which has already been recommended as an alternative anti-inflammatory treatment, may be also considered an important source of candidate molecules for biotechnological and biomedical uses, such as the treatment of parasitic diseases. METHODS: Africanized honeybee venom from Apis mellifera was fractionated by RP-C18-HPLC and the obtained melittin was incubated with promastigotes and intracellular amastigotes of Leishmania (L.) infantum. Cytotoxicity to mice peritoneal macrophages was evaluated through mitochondrial oxidative activity. The production of anti- and pro-inflammatory cytokines, NO and H2O2 by macrophages was determined. RESULTS: Promastigotes and intracellular amastigotes were susceptible to melittin (IC50 28.3 µg.mL(-1) and 1.4 µg.mL(-1), respectively), but also showed mammalian cell cytotoxicity with an IC50 value of 5.7 µg.mL(-1). Uninfected macrophages treated with melittin increased the production of IL-10, TNF-α, NO and H2O2. Infected melittin-treated macrophages increased IL-12 production, but decreased the levels of IL-10, TNF-α, NO and H2O2. CONCLUSIONS: The results showed that melittin acts in vitro against promastigotes and intracellular amastigotes of Leishmania (L.) infantum. Furthermore, they can act indirectly on intracellular amastigotes through a macrophage immunomodulatory effect.

Melittin induces in vitro death of Leishmania (Leishmania) infantum by triggering the cellular innate immune response

Abstract Background Apis mellifera venom, which has already been recommended as an alternative anti-inflammatory treatment, may be also considered an important source of candidate molecules for biotechnological and biomedical uses, such as the treatment of parasitic diseases. Methods Africanized honeybee venom from Apis mellifera was fractionated by RP-C18-HPLC and the obtained melittin was incubated with promastigotes and intracellular amastigotes of Leishmania (L.) infantum. Cytotoxicity to mice peritoneal macrophages was evaluated through mitochondrial oxidative activity. The production of anti- and pro-inflammatory cytokines, NO and H2O2 by macrophages was determined. Results Promastigotes and intracellular amastigotes were susceptible to melittin (IC50 28.3 μg.mL−1 and 1.4 μg.mL−1, respectively), but also showed mammalian cell cytotoxicity with an IC50 value of 5.7 μg.mL−1. Uninfected macrophages treated with melittin increased the production of IL-10, TNF-α, NO and H2O2. Infected melittin-treated macrophages increased IL-12 production, but decreased the levels of IL-10, TNF-α, NO and H2O2. Conclusions The results showed that melittin acts in vitro against promastigotes and intracellular amastigotes of Leishmania (L.) infantum. Furthermore, they can act indirectly on intracellular amastigotes through a macrophage immunomodulatory effect.

Atividade anti-leishmania e imunomodulatória in vitro da melitina natural na infecção experimental por Leishmania (L) infantum chagasi / Anti- leishmania activity and immunomodulatory in vitro natural melittin in experimental infection with Leishmania (L ) infantum chagasi

O objetivo deste trabalho foi avaliar o efeito da melitina natural na infecção experimental por Leishmania (L.) infantum chagasi, bem como seu efeito sobre a produção de citocinas pró e antinflamatórias e metabólitos do oxigênio e do nitrogênio. O fracionamento do veneno foi realizado por meio de cromatografia líquida de alta eficiência (HPLC-RP) usando-se colunas C8 e C18. As frações foram identificadas por sequenciamento peptídico pela química degradativa de Edman e espectrometria de massas do tipo eletrospray. A determinação da atividade anti-leishmania, contra formas promastigotas foi realizada de forma seriada partindo-se de uma concentração inicial de melitina de 100 μg/mL observando-se o valor de CE50 de 28,29 μg/mL. Foi realizado estudo de citotoxicidade em macrófagos peritoniais isolados de camundongos BALB/c, obtendo-se um valor de CE50 de 5,73 μg/mL. A viabilidade celular de ambos os ensaios foi avaliada por meio do estudo da atividade oxidativa mitocondrial (MTT). Os estudos em formas amastigotas intracelulares demostraram um valor de CE50 de 1,47 μg/mL. Quanto a produção de citocinas por celulas desafiadas com o parasita e tratados com a melitina observou-se que houve tendência de aumento para as citocinas inflamatórias IL12 e TNF-α nas concentrações utilizadas e nos respectivos períodos de tempo. A melitina não interferiu na produção de IFN-γ e TGF-β, porém observamos diminuição significativa nos níveis de IL-10, fato semelhante observado na produção de H2O2...

The purpose of this research was to evaluate the effect of natural melittin extracted and purified from the venom of Apis mellifera over an in vitro infection with Leishmania (L.) infantum chagasi, well as their effects on the production of proinflammatory and anti-inflammatory, and metabolites of oxygen and nitrogen. The fractionation of the venom was accomplished by high-performance liquid chromatography system (RP-HPLC) using C18 and C8 columns. These fractions were determined by peptide sequence using a combination of Edman degradation sequence analysis and electrospray ionization (ESI) mass spectrometry. The ascertainment of anti-leishmania activity against promastigote forms was conducted in a seriate form, beginning with an initial melittin concentration of 100μg/mL, noting an EC50 value of 28.29 μg/mL. Cytotoxicity study was conducted in isolated peritoneal macrophages from BALB/c mice, obtaining an EC50 value of 5.73μg/mL. The cell viability of both trials was assessed by means of the study of mitochondrial oxidative activity (MTT). The studies demonstrated an EC50 value of 1.47μg/mL on intracellular amastigotes. As the cytokines production by cells challenged with parasite and treated with melittin, was observed that there was an increased tendency for inflammatory cytokines IL-12 and TNF-α at used concentrations and in the respective periods of time analyzed. The melittin did not interfered in the IFN-γ and TGF-β production, however were observed a significant decrease in the IL- 10 levels, which was similarly observed in the H2O2 and NO production...

Abordagem fitoquímica, composição bromatológica e atividade antibacteriana de Mimosa tenuiflora (Wild) Poiret E Piptadenia stipulacea (Benth) Ducke / Phytochemical approach, bromatologic composition and antibacterial activity of Mimosa tenuiflora (Wild) Poiret and Piptadenia stipulacea (Benth) Ducke

A necessidade de encontrar novas drogas eficazes no combate microbiano tem aumentado a cada dia e estimulado a busca de novos compostos naturais com atividades biológicas. Neste trabalho, realizaram-se estudo fitoquímico e análises microbiológicas com os extratos etanólicos das espécies (jurema-preta) Mimosa tenuiflora (Wild) Poiret e (jurema-branca) Piptadenia stipulacea (Benth) Ducke, frente a linhagens de bactérias patogênicas. O pó da casca do caule de ambas as espécies foi submetido à avaliação bromatológica e determinados os teores de Matéria Seca, Matéria Mineral, Proteína Bruta, Fibra em Detergente Neutro e Energia Bruta. Os resultados para a prospecção química indicaram a presença de taninos e outros compostos fenólicos, bem como a presença de saponinas em ambos os extratos. Os extratos das duas espécies demonstraram que mais de uma parte das plantas possui atividade antimicrobiana. A composição bromatológica da casca do caule de jurema-preta e jurema-branca apresentou teores diferenciados para as variáveis avaliadas.

The need to find new efficient drugs to combat microbes has increased the search for new natural compounds with biological activities. In this work, phytochemical studies and microbiological analysis were carried out with the ethanol extracts of Mimosa tenuiflora (Wild) Poiret and Piptadenia stipulacea (Benth) Ducke on pathogenic bacteria strains. The bark powders of both species were submitted to bromatologic evaluation and the levels of dry matter, mineral matter, crude protein, neutral detergent fiber (NDF) and crude energy were determined. The results of the chemical search chemical showed the presence of tannins and other phenolic compounds as well as the presence of saponins in both extracts. The microbiologic evaluation of the extracts of both species showed that more than one part of the plants had antimicrobial activity. The bromatologic composition of the bark powder of Mimosa tenuiflora (Wild) Poiret and Piptadenia stipulacea (Benth) Ducke showed different contents for analyzed variables.

Atividade antifúngica in vitro do extrato da Uncaria Tomentosa L. (unha de gato) sobre cepas do gênero Candida / In vitro antifungic activity of Uncaria Tomentosa L. (cat's claw) against Candida

Objetivo: O objetivo deste estudo foi avaliar in vitro a ação antifúngica do extrato hidroalcóolico da Uncaria tomentosa L. (unha de gato) sobre cepas padrão de Candida albicans ATCC 36.232, Candida guilliermondii ATCC 6.260, Candida krusei ATCC 34.135 e Candida tropicalis ATCC 13.803, responsáveis por afecções bucais conhecidas por candidíases, ou candioses. Métodos: O material botânico utilizado para os testes foram o micropulverizado do caule da Uncaria tomentosa L., que em seguida foi submetido ao processo de maceração para preparação do extrato. Foram utilizadas linhagens padronizadas de microrganismos Candida (ATCC), obtidas mediante solicitação na Fundação Oswaldo Cruz, Rio de Janeiro. A atividade antimicrobiana e determinação da Concentração Inibitória Mínima (CIM) do extrato da Uncaria tomentosa L. foi determinada através da técnica de ágar-difusão em placas de Petri, meio sólido Agar Mueller Hington - DIFCO. Os mesmos procedimentos foram realizados com a clorexidina em concentração 0,12%, um anti-séptico oral utilizado como controle positivo nos experimentos. Resultados: Todas as espécies avaliadas apresentaram-se sensíveis ao extrato da Uncaria tomentosa L., atuando de forma semelhante à ação da clorexidina (controle positivo). As cepas apresentaram halos de inibição de crescimento até a diluição de 1:16 do extrato. Candida albicans foi o microorganismo que apresentou maior sensibilidade ao extrato da Uncaria tomentosa L., seguido de Candida guilliermondii, Candida krusei e Candida tropicalis. Conclusão: Os resultados deste estudo demonstram que a Uncaria tomentosa L., conhecida popularmente como unha de gato, possui compostos bioativos com atividade antimicrobiana sobre fungos do gênero candida, responsáveis pelas manifestações de candidíase bucal.

Objective: The aim of this study was to evaluate in vitro the antifungal effect of the hydroalcoholic extract of Uncaria tomentosa L. (Cat's Claw) on strains of Candida albicans ATCC 36232, Candida guilliermondii ATCC 6260, Candida krusei ATCC 34135 and Candida tropicalis ATCC 13 803, responsible for oral diseases known as candidiasis or candioses. Methods: The botanical material used in the tests were sputtered from the stem of Uncaria tomentosa L., which was then subjected to the maceration process for preparing the extract. We used standardized strains of Candida microorganisms (ATCC), obtained upon request at the Oswaldo Cruz Foundation, Rio de Janeiro. The antimicrobial activity and determination of Minimum Inhibitory Concentration (MIC) of the extract of Uncaria tomentosa L. was determined by agar-diffusion technique in Petri dishes, solid Mueller Hinton Agar - DIFCO. The same procedures were performed with the 0.12% chlorhexidine, an antiseptic used as positive control in the experiments. Results: All species evaluated were sensitive to the extract of Uncaria tomentosa L., operating similarly to the action of chlorhexidine (positive control). The strains showed inhibition zones of growth until the 1:16 dilution of the extract. Candida albicans was the microorganism that showed greater sensitivity to the extract of Uncaria tomentosa L., followed by Candida guilliermondii, Candida krusei and Candida tropicalis. Conclusion: The results of this study show that Uncaria tomentosa L., popularly known as cat's claw, has bioactive compounds with antimicrobial activity against fungi of the genus Candida are responsible for the manifestations of oral candidiasis.

Atividade antimicrobiana e antiaderente do extrato da Mimosa tenuiflora (Willd). Poir. Sobre microrganismos do biofilme dentário / Antimicrobial and ant-adherent activity of the Mimosa tenuifl ora (Willd) poir extract on dental biofilm microorganisms

Objetivo: Determinar a atividade antimicrobiana e a capacidade de inibição da síntese do glucano in vitro do extrato da casca de Mimosa tenuiflora (Willd.) Poir. (jurema preta) sobre linhagens formadoras do biofilme dental. Método: Utilizou-se as linhagens Streptococcus mitis (ATCC 9811), Streptococcus mutans (ATCC 25175), Streptococcus sanguinis (ATCC 10557), Streptococcus sobrinus (ATCC 27609) e Lactobacillus casei (ATCC 7469). Os ensaios foram realizados pelas técnicas de ágar-difusão em placas para determinação da Concentração Inibitória Mínima (CIM) e técnica dos tubos inclinados para determinação da Concentração Inibitória Mínima de Aderência (CIMA) ao vidro, na presença de 5% de sacarose. Resultados: As Concentrações Inibitórias Mínimas (mg/mL) do extrato da Mimosa tenuiflora frente ao S. mitis, S. mutans, S. sanguis, S. sobrinus e L. casei foram 1:64, 1:64, 1:16, 1:32 e 1:64 respectivamente. Para as Concentrações Inibitórias Mínimas de Aderência, o extrato da Mimosa tenuiflora apresentou maior efeito inibitório de aderência nas linhagens de L. casei e S. sobrinus na diluição de 1:32 e S. mitis, S. mutans e S. sanguinis na diluição de 1:16. Em estudo comparativo, foi determinada a CIM e CIMA do gluconato de clorexidina a 0,12% frente a esses microrganismos, demonstrando uma efetiva ação inibitória de ambas as substâncias. Conclusão: O extrato da Mimosa tenuifl ora (Willd.) Poir produziu uma significante atividade bactericida e efeito anti aderente in vitro sobre as bactérias formadoras do biofilme dental, o que sugere a utilização dessa substância como meio alternativo e economicamente viável para o controle de infecções em Odontologia.

Objective: To assess the in vitro anti microbial activity and the glucan synthesis inhibition capacity of the extract obtained from the bark of Mimosa tenuiflora (Willd) Poir on dental biofilm-forming microbial strains. Method: The following microbial strains were used: Streptococcus mitis (ATCC 9811), Streptococcus mutans (ATCC 25175), Streptococcus sanguinis (ATCC 10557), Streptococcus sobrinus (ATCC 27609) and Lactobacillus casei (ATCC 7469). The assays were performed by the agar diffusion technique to determine the minimum inhibitory concentration (MIC) and by the inclined tube technique to determine the minimum inhibitory concentration of adherence (MICA) to glass in the presence of 5% sucrose. Results: The MICs (mg/mL) of the Mimosa tenuiflora (Willd) Poir extract against S. mitis, S. mutans, S. sanguis, S. sobrinus and L. casei were 1:64, 1:64, 1:16, 1:32 and 1:64, respectively. Regarding the MICA, the Mimosa Tenuiflora (Willd) Poir extract presented the highest inhibitory effect against L. casei and S. sobrinus in the 1:32 dilution and against S. mitis, S. mutans and S. sanguinis in the 1:16 dilution. In a comparative analysis, the MIC and MICA of 0.12% chlorhexidine gluconate against the test microorganisms were also determined, demonstrating an effective inhibitory action of both substances. Conclusion: The Mimosa tenuiflora (Willd) Poir extract had a signifi cant in vitro bactericidal activity and anti-adherent effect against dental biofilm bacteria, which suggests the use of this substance as an alternative and cost-effective means for controlling dental infections.