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Mem. Inst. Oswaldo Cruz ; 115: e200349, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135262


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.

Humans , Candida/drug effects , Oils, Volatile , Cinnamomum zeylanicum/chemistry , Virulence Factors , Antifungal Agents
Braz. arch. biol. technol ; 63: e20200087, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132188


Abstract In the current study, nanocapsules (NC) formulations containing a co-load of clotrimazole (C), a highly prescribed antifungal drug, and diphenyl diselenide [(PhSe)2], an organoselenium compound with a promising scope of pharmacological actions, were prepared. Formulations were characterized as well as the potential toxicity, antioxidant action, and antifungal effect were assessed using in vitro techniques. The NCs were prepared employing Eudragit® RS 100 as polymeric wall and medium chain triglycerides or virgin coconut oil (CO) as core. All NC suspensions had pH around acid range, compound content close to theoretical value (1 mg/mL/drug), average diameter in nanometric range, positive values of zeta potential as well as high encapsulation efficacy and mucoadhesive property. Physicochemical stability was performed over a 30-day period and showed no modification in the aforementioned parameters to all samples. Preliminary screening of toxicological potential performed by the hen's egg test chorioallantoic membrane technique classified the formulations as non-irritant. The DPPH radical assay revealed that nanoencapsulated compounds had superior antioxidant action in comparison to their free forms (concentration range tested 1.0-25.0 µg/mL). Importantly, the formulation composed of CO and containing C and (PhSe)2 showed the highest antioxidant potential and was selected for further investigation regarding antifungal effect against some Candida spp strains. Results of in vitro antifungal assay demonstrated that the C and (PhSe)2 co-encapsulation had a minimum inhibitory concentration (MIC) values around 60. Thus, our study supplies additional data about advantages achieved by encapsulating active compounds.

Benzene Derivatives/pharmacology , Candida/drug effects , Organoselenium Compounds/pharmacology , Clotrimazole/pharmacology , Nanocapsules , Antifungal Agents/pharmacology , Antioxidants/pharmacology , Microbial Sensitivity Tests
Braz. j. biol ; 79(3): 432-437, July-Sept. 2019. tab, graf
Article in English | LILACS | ID: biblio-1001460


Abstract The aims of this research were: evaluate the chemical composition and the cytotoxicity of the Cuminum cyminum (cumin), Anethum graveolens (dill), Pimpinella anisum (anise) and Foeniculum vulgare (fennel) essential oils, as well as their antifungal activity in vitro against ten Candida spp. isolates. The chemical composition of the oils was analyzed by means of gas chromatography coupled with mass spectrometry (GC/MS). The cytotoxicity assays were performed, using the cell proliferation reagent WST-1 in L929 mouse fibroblasts (20x103 well-1). The determinate the Minimum Inhibitory Concentration (MIC), was performed through the Broth Microdilution technique (CLSI). The chemical main components were the cuminaldehyde (32.66%) for cumin, carvone (34.89%) for the dill, trans-anethole (94.01%) for the anise and anethole (79.62%) for the fennel. Anise and fennel did not were cytotoxic in all the tested concentrations, however the cumin oil was cytotoxic in the concentration of 20 mg.mL-1 and the dill in the concentrations of 20 and 8 mg.mL-1. All yeasts were susceptible against the evaluated essential oils. Cumin presented the lowest MIC against yeasts. We concluded that all the essential oils presented inhibitory action against Candida spp., and C . cyminum, P. anisum and F. vulgare were not cytotoxic in the same minimum inhibitory concentrations for the fungi.

Resumo Os objetivos desta pesquisa foram: avaliar a composição química e a citotoxicidade dos óleos essenciais de Cuminum cyminum (cominho), Anethum graveolens (endro), Pimpinella anisum (erva-doce) e Foeniculum vulgare (funcho), bem como sua atividade antifúngica in vitro contra dez isolados de Candida spp.. A composição química dos óleos foi analisada por meio de cromatografia gasosa acoplada à espectrometria de massa (GC / MS). Os ensaios de citotoxicidade foram realizados, utilizando o reagente de proliferação celular WST-1 em fibroblastos de ratinho L929 (20x103 poço-1). A determinação da Concentração Inibitória Mínima (MIC) foi realizada através da técnica de microdiluição em caldo (CLSI). Os principais componentes químicos foram o cuminaldeído (32.66%) para cominho, carvona (34.89%) para o endro, trans-anetol (94.01%) para erva-doce e anetol (79.62%) para a funcho. O endro e a erva-doce não foram citotóxicos em todas as concentrações testadas, no entanto, o óleo de cominho foi citotóxico na concentração de 20 mg.mL-1 e o endro nas concentrações de 20 e 8 mg.mL-1. Todas as leveduras foram suscetíveis aos óleos essenciais avaliados. O cominho apresentou a menor CIM contra as leveduras. Concluímos que todos os óleos essenciais apresentaram ação inibidora contra Candida spp., e C. cyminum, P. anisum e F. vulgare não foram citotóxicos nas mesmas concentrações inibitórias mínimas para os fungos.

Candida/drug effects , Oils, Volatile/pharmacology , Apiaceae/chemistry , Antifungal Agents/pharmacology , In Vitro Techniques , Microbial Sensitivity Tests , Gas Chromatography-Mass Spectrometry , Mouth/microbiology
Clin. biomed. res ; 39(4): 341-345, 2019.
Article in Portuguese | LILACS | ID: biblio-1087506


O gênero Candida possui várias espécies conhecidas e que podem tornar-se patogênicas em determinadas situações. Candida blankii é uma espécie emergente que, na última década, foi identificada como um agente de doenças sistêmicas. Ainda não existe um protocolo de tratamento específico, apesar de que n os poucos casos registrados na literatura a terapia adotada foi efetiva. O objetivo deste estudo foi realizar uma revisão bibliográfica para coletar informações relevantes sobre este patógeno como um possível agente etiológico em infecções sistêmicas, bem como sua epidemiologia e os aspectos de sua patogenicidade. (AU)

The genus Candida has several known species and may become pathogenic in certain situations. Candida blankii is an emerging species that in the past decade has been identified as an agent of systemic diseases. There is no specific treatment protocol yet, although in the few cases reported in the literature the therapy adopted was effective. The objective of this study was to conduct a literature review to collect relevant information about this pathogen as a possible etiological agent in systemic infections, as well as its epidemiology and aspects of pathogenicity. (AU)

Humans , Candida/classification , Candida/drug effects , Candida/pathogenicity , Communicable Diseases, Emerging/genetics , Drug Resistance, Fungal/genetics , Disease Susceptibility/epidemiology
Braz. oral res. (Online) ; 33: e023, 2019. tab, graf
Article in English | LILACS | ID: biblio-1001611


Abstract: We evaluated the antifungal and antibiofilm potential of the hydroalcoholic extract of bark from Anadenanthera colubrina (vell.) Brenan, known as Angico, against Candida spp. Antifungal activity was evaluated using the microdilution technique through the Minimum Inhibitory and Fungicide Concentrations (MIC and MFC). The antibiofilm potential was tested in mature biofilms formed by Candida species and analyzed through the counting of CFU/mL and scanning electron micrograph (SEM). In vivo toxicity and therapeutic action was evaluated in the Galleria mellonella model. The treatment with the extract, in low doses, was able to reduce the growth of planktonic cells of Candida species. MIC values range between 19.5 and 39 µg/mL and MFC values range between 79 and 625 µg/mL. In addition was able to reduce the number of CFU/mL in biofilms and to cause structural alteration and cellular destruction, observed via SEM. A. colubrina showed low toxicity in the in vivo assay, having not affected the viability of the larvae at doses below 100mg/kg and high potential in the treatment of C. albicans infection. Considering its high antifungal potential, its low toxicity and potential to treatment of infections in in vivo model, A. colubrina extract is a strong candidate for development of a new agent for the treatment of oral candidiasis.

Candida/drug effects , Plant Extracts/pharmacology , Biofilms/drug effects , Fabaceae/chemistry , Antifungal Agents/pharmacology , Time Factors , Microscopy, Electron, Scanning , Colony Count, Microbial , Microbial Sensitivity Tests , Nystatin/pharmacology , Reproducibility of Results , Analysis of Variance
Rev. Soc. Bras. Med. Trop ; 52: e20180473, 2019. tab
Article in English | LILACS | ID: biblio-990445


Abstract INTRODUCTION: Candidiasis is the most frequent opportunistic mycosis in humans and can cause mortality, particularly in immunodeficient patients. One major concern is the increasing number of infections caused by drug-resistant Candidas trains, as these cannot be efficiently treated with standard therapeutics. The most common mechanism of fluconazole resistance in Candida is mutation of ERG11, a gene involved in the biosynthesis of ergosterol, a compound essential for cell integrity and membrane function. METHODS: Based on this knowledge, we investigated polymorphisms in the ERG11 gene of 3 Candida species isolated from immunocompromised and immunocompetent patients. In addition, we correlated the genetic data with the fluconazole susceptibility profile of the Candida isolates. RESULTS: A total of 80 Candida albicans, 8 Candida tropicalis and 6 Candida glabrata isolates were obtained from the saliva of diabetic, kidney transplant and immunocompetent patients. Isolates were considered susceptible to fluconazole if the minimum inhibitory concentration was lower than 8 μg/mL. The amino acid mutations F105L, D116E, K119N, S137L, and K128T were observed in C. albicans isolates, and T224C and G263A were found in C. tropicalis isolates. CONCLUSIONS: Despite the high number of polymorphisms observed, the mutations occurred in regions that are not predicted to interfere with ergosterol synthesis, and therefore are not related to fluconazole resistance.

Humans , Male , Female , Adult , Aged , Polymorphism, Genetic/drug effects , Candida/drug effects , Candida/genetics , Fluconazole/pharmacology , Kidney Transplantation , Diabetes Mellitus/microbiology , Antifungal Agents/pharmacology , Reference Values , Saliva/microbiology , Candida/isolation & purification , DNA, Fungal/genetics , Microbial Sensitivity Tests , Polymerase Chain Reaction , Drug Resistance, Fungal/genetics , Immunocompetence , Middle Aged , Mutation/drug effects
Rev. Soc. Bras. Med. Trop ; 52: e20180152, 2019. tab, graf
Article in English | LILACS | ID: biblio-1041546


Abstract INTRODUCTION: Introducing new antibiotics to the clinic is critical. METHODS: We adapted a plate method described by Kawaguchi and coworkers in 20131 for detecting inhibitory airborne microorganisms. RESULTS: We obtained 51 microbial colonies antagonist to Chromobacterium violaceum, purified and retested them, and of these, 39 (76.5%) were confirmed. They comprised 24 bacteria, 13 fungi, and 2 yeasts. Among the fungi, eight (61.5%) produced active extracts. Among the bacterial, yeast, and fungal strains, 17 (44.7%) and 12 (31.6%) were active against Candida albicans and Candida parapsilosis, respectively. CONCLUSIONS: The proposed screening method is a rapid strategy for discovering potential antibiotic producers.

Bacteria/isolation & purification , Candida/drug effects , Chromobacterium/drug effects , Air Microbiology , Quorum Sensing , Fungi/isolation & purification , Anti-Bacterial Agents/isolation & purification , Bacteria/metabolism , Colony Count, Microbial , Fungi/metabolism , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology
Braz. j. biol ; 78(4): 742-749, Nov. 2018. tab, graf
Article in English | LILACS | ID: biblio-951595


Abstract Although invasive infections and mortality caused by Candida species are increasing among compromised patients, resistance to common antifungal agents is also an increasing problem. We analyzed 60 yeasts isolated from patients with invasive candidiasis using a PCR/RFLP strategy based on the internal transcribed spacer (ITS2) region to identify different Candida pathogenic species. PCR analysis was performed from genomic DNA with a primer pair of the ITS2-5.8S rDNA region. PCR-positive samples were characterized by RFLP. Restriction resulted in 23 isolates identified as C. albicans using AlwI, 24 isolates as C. parapsilosis using RsaI, and 13 as C. tropicalis using XmaI. Then, a group of all isolates were evaluated for their susceptibility to a panel of previously described killer yeasts, resulting in 75% being susceptible to at least one killer yeast while the remaining were not inhibited by any strain. C. albicans was the most susceptible group while C. tropicalis had the fewest inhibitions. No species-specific pattern of inhibition was obtained with this panel of killer yeasts. Metschnikowia pulcherrima, Pichia kluyveri and Wickerhamomyces anomalus were the strains that inhibited the most isolates of Candida spp.

Resumo Embora as infecções invasivas e a mortalidade causada por espécies de Candida estejam aumentando entre pacientes comprometidos, a resistência a agentes antifúngicos comuns também é um problema crescente. Analisamos 60 leveduras isoladas de pacientes com candidíase invasiva utilizando como estratégia PCR/RFLP baseada na região espaçadora transcrita interna (ITS2) para identificar diferentes espécies patogênicas de Candida. A análise por PCR foi realizada a partir de ADN genómico com um par de iniciadores da região ITS2-5.8S rDNA. As amostras PCR-positivas foram caracterizadas por RFLP. A restrição resultou em 23 isolados identificados como C. albicans usando AlwI, 24 isolados como C. parapsilosis usando RsaI e 13 como C. tropicalis usando XmaI. Em seguida, avaliou-se o grupo de todos os isolados quanto à sua susceptibilidade a um painel de leveduras killer previamente descritas, resultando em 75% sendo suscetíveis a pelo menos uma levedura killer, enquanto que as restantes não foram inibidas por qualquer cepa. C. albicans foi o grupo mais suscetível enquanto C. tropicalis teve o menor número de inibições. Não se obteve um padrão de inibição específico da espécie com este painel de leveduras killer. Metschnikowia pulcherrima, Pichia kluyveri e Wickerhamomyces anomalus foram as cepas que inibiram a maioria dos isolados de Candida spp.

Humans , Adult , Candida/drug effects , Candidiasis, Invasive/drug therapy , Antifungal Agents/pharmacology , Polymorphism, Restriction Fragment Length , Candida/genetics , Microbial Sensitivity Tests/methods , Polymerase Chain Reaction/methods , Candidiasis, Invasive/microbiology
Braz. j. biol ; 78(4): 673-678, Nov. 2018. tab, graf
Article in English | LILACS | ID: biblio-951612


Abstract Amphotericin B is a fungicidal substance that is treatment of choice for most systemic fungal infections affecting immunocompromised patients. However, severe side effects have limited the utility of this drug. The aim of this study was to evaluate the antifungal effect of the combination of amphotericin B with black tea or white tea and protective of citotoxic effect. The present study shows that white and black teas have additive effects with amphotericin B against some species Candida. In addition, the combination of white and black tea with amphotericin B may reduce the toxicity of amphotericin B to red blood cells. Our results suggest that white and black tea is a potential agent to combine with amphotericin for antifungal efficacy and to reduce the amphotericin dose to lessen side effects.

Resumo A anfotericina B é o tratamento de escolha para a maioria das infecções fúngicas sistémicas que afetam os doentes imunocomprometidos. No entanto, efeitos secundários graves têm limitado a utilidade desta droga. O objetivo deste estudo foi avaliar o efeito antifúngico da combinação de anfotericina B com chá preto ou chá branco, bem como o efeito citotóxico desta combinação sobre hemáceas. O presente estudo demonstra que o chá branco e preto de Camellia sinensis têm efeitos aditivos com anfotericina B contra algumas espécies de Candida sp. Além disso, a combinação de chá branco e preto com anfotericina B pode reduzir a toxicidade da anfotericina B em hemáceas. Nossos resultados sugerem que o chá branco e preto são agentes potenciais para associação com anfotericina B contribuindo para eficácia antifúngica, bem como redução de toxicidade.

Humans , Candida/drug effects , Amphotericin B/pharmacology , Camellia sinensis/adverse effects , Erythrocytes/drug effects , Antifungal Agents/pharmacology , Amphotericin B/adverse effects , Hemolysis/drug effects , Antifungal Agents/adverse effects
Rev. Soc. Bras. Med. Trop ; 51(5): 644-650, Sept.-Oct. 2018. tab, graf
Article in English | LILACS | ID: biblio-957457


Abstract INTRODUCTION: The increase in the incidence of fungal infections, especially those caused by Candida albicans and other Candida species, necessitates the understanding and treatment of Candida-associated infections. In this study, we aimed to investigate the identification, distribution, and biofilm formation ability of different clinical Candida isolates and evaluate the distribution and antifungal susceptibilities of high biofilm-forming (HBF) Candida isolates. METHODS: For identification, carbohydrate fermentation, carbohydrate assimilation, and ChromAgar tests were used. Biofilm formation was assessed using crystal violet binding assay, while the susceptibility to antifungal agents was determined using ATBTM Fungus 3 test kits. RESULTS: The majority of Candida species were C. parapsilosis (31.3%; 31/99) and C. tropicalis (30.3%; 30/99). C. tropicalis was found to be the most frequently isolated species among all HBF Candida species. HBF Candida isolates were more frequently isolated from vaginal swab (35.7%; 10/28), tracheal aspirate (17.9%; 5/28), and urine (17.9%; 5/28). The majority of tested isolates were resistant to itraconazole and voriconazole, whereas no isolate was deemed resistant to 5-flucytosine. CONCLUSIONS: C. tropicalis displays the highest biofilm formation ability among all the Candida species evaluated, and HBF Candida isolates were more frequently seen in vaginal swab, tracheal aspirate, and urine samples. Our findings revealed that 5-flucytosine is the most efficient antifungal agent against HBF Candida isolates.

Humans , Candida/drug effects , Biofilms/drug effects , Antifungal Agents/pharmacology , Candida/classification , Candida/physiology , Microbial Sensitivity Tests , Biofilms/growth & development
Rev. Soc. Bras. Med. Trop ; 51(4): 542-545, July-Aug. 2018. tab
Article in English | LILACS | ID: biblio-1041473


Abstract INTRODUCTION This study aims to evaluate the antifungal susceptibility of different species of Candida isolated from diabetic patients against eight antifungal agents. METHODS Susceptibility testing of 111 clinical isolates of Candida species was performed against 8 antifungals using the M27-A3 protocol of the Clinical and Laboratory Standards Institute (CLSI). RESULTS Voriconazole, lanoconazole, and caspofungin showed the highest in vitro activity against all the isolates of C. albicans. Resistance against the tested antifungals was only observed in the C. albicans isolates. CONCLUSIONS Our finding revealed that resistance against amphotericin B, itraconazole, ketoconazole, posaconazole, and fluconazole can be observed in C. albicans.

Humans , Male , Female , Adult , Aged , Aged, 80 and over , Candida/drug effects , Diabetes Mellitus/microbiology , Antifungal Agents/pharmacology , Candida/isolation & purification , Candida/classification , Microbial Sensitivity Tests/methods , Middle Aged
Rev. Soc. Bras. Med. Trop ; 51(3): 352-356, Apr.-June 2018. tab
Article in English | LILACS | ID: biblio-1041467


Abstract INTRODUCTION We describe the clinical and laboratorial features of oral candidiasis in 66 HIV-positive patients. METHODS: Polymerase chain reaction-based techniques were performed for differentiation of Candida spp. isolated from patients at a public teaching hospital in Midwest Brazil. RESULTS: Oral lesions, mainly pseudomembranous, were significantly related to higher levels of immunosuppression. Of 45 Candida isolates, 66.7% were C. albicans. Most of the isolates were susceptible to the antifungal drugs tested. CONCLUSIONS: Oral lesions were associated with higher immunosuppression levels. Lower susceptibility to antifungals by non-albicans isolates supports the importance of surveillance studies using susceptibility tests to aid in the treatment.

Humans , Male , Female , Adult , Young Adult , Candida/drug effects , Candidiasis, Oral/diagnosis , AIDS-Related Opportunistic Infections/diagnosis , Antifungal Agents/pharmacology , Brazil , Candida/isolation & purification , Candida/classification , Candidiasis, Oral/microbiology , Drug Resistance, Microbial , Microbial Sensitivity Tests , Fluconazole/pharmacology , Amphotericin B/pharmacology , Mycological Typing Techniques , AIDS-Related Opportunistic Infections/microbiology , Itraconazole/pharmacology , Middle Aged
Braz. j. microbiol ; 49(2): 212-219, Apr.-June 2018. tab
Article in English | LILACS | ID: biblio-889241


Abstract The evolution of microorganisms resistant to many medicines has become a major challenge for the scientific community around the world. Motivated by the gravity of such a situation, the World Health Organization released a report in 2014 with the aim of providing updated information on this critical scenario. Among the most worrying microorganisms, species from the genus Candida have exhibited a high rate of resistance to antifungal drugs. Therefore, the objective of this review is to show that the use of natural products (extracts or isolated biomolecules), along with conventional antifungal therapy, can be a very promising strategy to overcome microbial multiresistance. Some promising alternatives are essential oils of Melaleuca alternifolia (mainly composed of terpinen-4-ol, a type of monoterpene), lactoferrin (a peptide isolated from milk) and chitosan (a copolymer from chitin). Such products have great potential to increase antifungal therapy efficacy, mitigate side effects and provide a wide range of action in antifungal therapy.

Anti-Infective Agents/pharmacology , Biological Products/pharmacology , Candida/drug effects , Chitosan/pharmacology , Lactoferrin/pharmacology , Melaleuca/chemistry , Anti-Infective Agents/isolation & purification , Biological Products/isolation & purification , Candidiasis/drug therapy , Chitosan/isolation & purification , Lactoferrin/isolation & purification
Braz. j. biol ; 78(2): 368-374, May-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-888882


Abstract This study analyzed the antifungal activity of phytoconstituents from linalool on Candida spp. strains, in vitro, isolated from patients with clinical diagnoses of oral candidiasis associated with the use of a dental prosthesis. Biological samples were collected from 12 patients using complete dentures or removable partial dentures and who presented mucous with diffuse erythematous or stippled features, indicating a clinical diagnosis of candidiasis. To identify fungal colonies of the genus Candida, samples were plated onto CHROMagar Candida®. The antifungal activity of linalool, a monoterpene unsaturated constituent of basil oil, was performed using the broth microdilution technique. Then, the minimum inhibitory concentration (MIC), the two subsequent stronger concentrations and the positive controls were subcultured on Sabouraud Dextrose Agar plates to determine the minimum fungicidal concentration (MFC). The experiments were performed in triplicate and nystatin was used as a positive control in all tests. Diagnoses of oral candidiasis were verified in eight patients (66.6%) and the most prevalent fungal species was Candida albicans (37.5%), followed by Candida krusei (25.0%); and Candida tropicalis (4.2%). The best antifungal activity of linalool was observed on Candida tropicalis (MIC = 500 mg/mL), followed by Candida albicans (MIC = 1.000 mg/mL), and Candida krusei (MIC = 2.000 mg/mL).Under the study conditions and based on the results obtained, it can be concluded that the Candida strains tested were susceptible to linalool.

Resumo Este estudo analisou a atividade antifúngica do fitoconstituinte linalol em cepas de Candida ssp, in vitro, isolados de pacientes com o diagnóstico clínico de candidíase oral associado ao uso de prótese dentária. As amostras biológicas foram coletadas de 12 pacientes portadores de próteses totais ou próteses parciais removíveis e que apresentavam características de mucosa eritematosa difusa ou pontilhadas, indicando um diagnóstico clínico de candidíase. Para identificar colônias de fungos do gênero Candida, as amostras foram semeadas em CHROMagar Candida®. A atividade antifúngica do linalol, um componente insaturado monoterpene de óleo de manjericão, foi realizada através da técnica de microdiluição em caldo. Em seguida, a concentração inibitória mínima (MIC), as duas concentrações consecutivas mais fortes e os controles positivos foram subcultivados em placas de Agar Sabouraud Dextrose para determinar a concentração fungicida mínima (MFC). Os experimentos foram realizados em triplicata e a nistatina foi usada como controle positivo em todos os testes. O diagnóstico de candidíase oral foi comprovado em oito pacientes (66,6%) e as espécies de fungos mais prevalentes foram Candida albicans (37,5%), seguido por Candida krusei (25,0%); e Candida tropicalis (4,2%). A melhor atividade antifúngica do linalol foi observada em Candida tropicalis (MIC = 500 mg/ml), seguido por Candida albicans (CIM = 1,000 mg/mL), e Candida krusei (CIM = 2,000 mg/mL). Sob as condições do estudo e com base nos resultados obtidos, pode-se concluir que as estirpes de Candida testadas foram susceptíveis a linalol.

Humans , Candida/drug effects , Candidiasis, Oral/microbiology , Monoterpenes/pharmacology , Antifungal Agents/pharmacology , Microbial Sensitivity Tests , Acyclic Monoterpenes
Bol. latinoam. Caribe plantas med. aromát ; 17(3): 270-285, mayo 2018. mapas, tab
Article in English | LILACS | ID: biblio-915369


Twenty-eight native plants mainly used to cure diseases related to microbial infection and stress oxidative disorders were selected to test the antimicrobial activity against E. coli, P. aeruginosa, S. aureus, B. subtilis, and C. albicans using diffusion and microdilution methods. The antioxidant activity was determined by scavenging DPPH free-radical and phytochemical evaluation was performed for plants with promising activities. Twenty-seven plants showed antibacterial activity, four had anti-Candida activity, and four showed antioxidant activity. It was found that Oreocallis grandiflora, Gentianella weberbaueri, Gamochaeta americana, Hypericum laricifolium, Loricaria ferruginea, Muehlenbeckia volcanica, and Oenothera multicaulis, showed promising biological activity and contained alkaloids, phenolic compounds, flavonoids, catecholic or gallic tannins. This study leaves evidence about the medicinal potential of wild high-Andean plants; thus, further pharmacological, phytochemical, ecological and biotechnological studies will contribute to promote their conservation and sustainable use; especially since they are highly vulnerable and risk extinction.

Se seleccionó veintiocho plantas nativas usadas principalmente para tratarcurar enfermedades relacionadas principalmente con infecciones microbianas y desordenes oxidativos. A estas plantas se para ser evaluóados en su actividad antimicrobiana sobre E. coli, P. auriginosa, S. aureus, B. subtilis, y C. albicans usando métodos de difusión y microdilución. Se determinó la actividad antioxidante mediante el ensayo del libre radical DPPH y se realizó la evaluación fitoquímica de las plantas con actividades promisorias. Veinte siete plantas mostraron actividad antibacteriana, cuatro mostraron actividad anti-Candida, y cuatro actividad antioxidante. Oreocallis grandiflora, Gentianella weberbaueri, Gamochaeta americana, Hypericum laricifolium, Loricaria ferruginea, Muehlenbeckia volcanica, y Oenothera multicaulis mostraron actividad biológica promisoria, y se encontró que contienen alcaloides, compuestos fenólicos, flavonoides, taninos gálicos y catecólicos. Este estudio deja evidencia del potencial medicinal de las plantas silvestres alto andinas; por lo tanto, los estudios farmacológicos, fitoquímicos, ecológicos y biotecnológicos contribuirían en la promoción de su conservación y uso sustentable debido a su alta vulnerabilidad y riesgo de extinción.

Plants, Medicinal/chemistry , Plant Extracts/pharmacology , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Peru , Bacteria/drug effects , Candida/drug effects , Plant Extracts/chemistry , Microbial Sensitivity Tests , Free Radical Scavengers , Andean Ecosystem , Anti-Bacterial Agents/chemistry , Antifungal Agents/pharmacology , Antioxidants/chemistry
Med. infant ; 25(1): 17-21, marzo 2018. tab
Article in Spanish | LILACS | ID: biblio-883427


Introducción: La frecuencia de las candidemias ha aumentado en los últimos años asociada principalmente a internación prolongada, antibióticos de amplio espectro y enfermedades de base. Se produjo también un cambio en la distribución y un aumento en la resistencia a los antifúngicos de las distintas especies de Candida spp., todo esto asociado a una elevada morbimortalidad. En este trabajo realizado durante un año en un hospital de alta complejidad, se incluyeron 33 pacientes con candidemia. La mediana de la edad fue de 22 meses y un 60% de los afectados fueron varones. El 97% de los niños tenían enfermedad de base con predominio de la patología oncohematológica. Un 88% presentó algún procedimiento o condición predisponente para la infección, principalmente portación de catéter venoso central y cirugía previa. En un 59% de los aislamientos predominaron especies de Candida diferentes de Candida albicans. Anfotericina B desoxicolato fue el tratamiento empírico de elección. La mediana de tratamiento fue de 21 días y la de internación de 66 días. La mortalidad fue del 12% y se asoció a ingreso a UCI, presencia de fiebre al momento del diagnóstico y requerimiento de ARM (AU)

The incidence of candidemia has increased over the past years mainly associated with prolonged hospital stay, wide-spectrum antibiotics, and underlying diseases. At the same time there has been a change in the distribution and an increase in the resistance to antifungals in different Candida spp, associated with a high morbidity and mortality. In this study, conducted during one year at a tertiary hospital, 33 patients with candidemia were included. Median age was 22 months and 60% of the patients were boys. Overall, 97% of the children had an underlying hematology-oncology disease. Of the patients, 88% underwent a procedure or had a condition that predisposed to infection, mainly the placement of a central venous catheter and previous surgery. In 59% the isolated Candida species were Candida albicans. Amphotericin B deoxycholate was the empirical treatment of choice. Median time of treatment was 21 days and median hospital stay was 66 days. Mortality was 12% and was associated with ICU admission, presence of fever at the time of diagnosis, and requirement of mechanical ventilation (AU)

Humans , Infant , Child, Preschool , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Candida/drug effects , Candida/isolation & purification , Candidemia/epidemiology , Candidemia/mortality , Child, Hospitalized , Drug Resistance, Fungal , Incidence , Observational Study , Retrospective Studies
Braz. oral res. (Online) ; 32: e41, 2018. tab, graf
Article in English | LILACS | ID: biblio-889473


Abstract: The aim of this study was to evaluate in vitro the antifungal, antibiofilm and antiproliferative activities of the extract from the leaves of Guapira graciliflora Mart. The phytochemical characterization of the extract was performed using electrospray ionization mass spectrometry (ESI-MS). The antimicrobial activity of the extract and its fractions was evaluated using the broth microdilution method against species of Candida. The inhibition of C. albicans biofilm was evaluated based on the number of colony-forming units (CFU) and metabolic activity (MTT). The antiproliferative activity of the extract and its fraction was evaluated in the presence of human tumor and non-tumor cells, and the cytotoxicity of the extract was determined on the RAW 264.7 macrophage line - both using the sulforhodamine B method. The phytochemical characterization indicated the presence of the flavonoids rutin and kaempferol. The extract and the methanol fraction exhibited moderate antifungal activity against C. albicans, C. krusei, and C. glabrata, and strong activity against C. dubliniensis. In the biofilms at 24 and 48 hours, the concentration of 12500 µg/mL of the extract was the most effective at reducing the number of CFU s/mL (44.4% and 42.9%, respectively) and the metabolic activity of C. albicans cells (34.6% and 52%, respectively). The extract and its fractions had no antiproliferative effect on the tumor lines tested, with mean activity (log GI50) equal to or greater than 1.71 µg/mL. Macrophage cell viability remained higher than 80% for concentrations of the extract of up to 62.5 µg/mL. G. graciliflora has flavonoids in its chemical composition and demonstrates potential antifungal and antibiofilm activity, with no evidence of a significant change in the viability of human tumor and non-tumor cell lines.

Candida/drug effects , Plant Extracts/pharmacology , Biofilms/drug effects , Nyctaginaceae/chemistry , Cell Proliferation/drug effects , Antifungal Agents/pharmacology , Microbial Sensitivity Tests , Cell Survival/drug effects , Biofilms/growth & development , Lethal Dose 50 , Antifungal Agents/isolation & purification
Einstein (Säo Paulo) ; 16(3): eAO4224, 2018. tab
Article in English | LILACS | ID: biblio-953168


ABSTRACT Objective To investigate antifungal susceptibility and factors associated with oral colonization by Candida species in HIV-positive patients. Methods A prospective study based on convenience sampling of subjects recruited from a pool of confirmed HIV-positive individuals seen at a specialty outpatient service in Rondonópolis, Mato Grosso, Brazil). Oral swabs were collected from 197 patients. Candida species were identified by standard microbiological techniques (phenotypic and molecular methods). Antifungal susceptibility was investigated using the broth microdilution method. Results A total of 101 (51.3%) patients were Candida spp carriers. Candida albicans was the most prevalent species (80%). Patients aged 45 to 59 years (Prevalence ratios: 1.90; 95%CI: 1.57-6.31) and 60 years or older (Prevalence ratios: 4.43; 95%CI: 1.57-34.18) were at higher risk of oral colonization by Candida species. Resistance to fluconazole and ketoconazole, or to itraconazole, corresponded to 1% and 4%, respectively. Conclusion Age (45 years or older) was the only factor associated with oral colonization by Candida . Low rates of antifungal resistance to azoles were detected in yeast isolates obtained from HIV-positive patients. Findings of this study may contribute to proper therapeutic selection for oral candidiasis in HIV-positive patients.

RESUMO Objetivo Investigar a suscetibilidade a antifúngicos e os fatores associados à colonização oral por espécies de Candida isoladas de pacientes HIV positivo. Métodos Estudo prospectivo realizado com amostragem por conveniência de indivíduos HIV positivo, acompanhados por um serviço de atendimento especializado da cidade de Rondonópolis, Mato Grosso, Brasil. Foram coletados swabs orais de 197 pacientes. As espécies de Candida foram identificadas por técnicas microbiológicas fenotípicas padrão e por método molecular. A suscetibilidade antifúngica foi determinada pelo método de microdiluição em caldo. Resultados Cento e um (51,3%) pacientes foram colonizados por Candida spp. Candida albicans foi a espécie mais prevalente (80%). Identificou-se um maior risco de colonização oral por espécies de Candida em pacientes com idade entre 45 e 59 anos (razão de prevalência: 1,90; IC95%: 1,57-6,31) e 60 anos ou mais (razão de prevalência: 4,43; IC95%: 1,57-34,18). A resistência ao fluconazol e ao cetoconazol foi de 1% cada e de 4% ao itraconazol. Conclusão O único fator associado à colonização oral por espécies de Candida foi ter 45 anos ou mais. Identificamos baixa taxa de resistência antifúngica aos azóis entre as leveduras isoladas de pacientes HIV positivo. Estes achados podem contribuir para selecionar o tratamento da candidíase oral em pacientes HIV positivos.

Humans , Male , Female , Adult , Young Adult , Candida/drug effects , Candidiasis, Oral/microbiology , Fluconazole/pharmacology , HIV Infections/complications , Itraconazole/pharmacology , Drug Resistance, Fungal , Antifungal Agents/pharmacology , Brazil/epidemiology , Candida/isolation & purification , Candida/classification , Candidiasis, Oral/drug therapy , Candidiasis, Oral/epidemiology , Microbial Sensitivity Tests , Prevalence , Prospective Studies , Middle Aged