Antimicrobial Effect of the Amniotic Membrane Isolated and Associated with Photodynamic Therapy.

Microbial control through alternative therapies, such as the amniotic membrane (AM) and antimicrobial photodynamic therapy (aPDT), has been gaining prominence with the advancement of bacterial resistance to conventional treatments. This study aimed to evaluate the antimicrobial effect of AM isolated and associated with aPDT using the PHTALOX® as a photosensitizer (PS) against Staphylococcus aureus and Pseudomonas aeruginosa biofilms. The groups studied were: C+; L; AM; AM+L; AM+PHTX; and AM+aPDT. The irradiation parameters were 660 nm, 50 J.cm-2, and 30 mW.cm-2. Two independent microbiological experiments were carried out in triplicate, and the results were analyzed by CFU/mL counting and a metabolic activity test, both statistically analyzed (p < 0.05). The integrity of the AM was verified after the treatments by a scanning electron microscope (SEM). The groups AM, AM+PHTX, and, mainly, AM+aPDT showed a statistical difference when compared to C+ regarding the decrease in CFU/mL and metabolic activity. SEM analysis showed significant morphological alterations in the AM+PHTX and AM+aPDT groups. The treatments with AM isolated or associated with PHTALOX® were adequate. The association had potentiated the biofilm effect, and the morphological differences presented by AM after treatment did not hinder its antimicrobial effect, encouraging its use in biofilm formation locals.

Effect of ozonized olive oil on oral levels of Candida spp. in patients with denture stomatitis / Efeito do óleo de oliva ozonizado sobre os níveis orais de Candida spp. em pacientes com estomatite protética

Objective: The aim of this study was to evaluate the effect of ozonized olive oil (OZ) on the oral levels of Candida spp. in patients with denture stomatitis. Material and Methods: In vitro tests were performed to validate antifungal activity and to standardize OZ conditions. Antifungal activity was screened against C. albicans and five non-albicans species (C. tropicalis, C. dubliniensis, C. krusei, C. guilliermondii, and C. parapsilosis). Also, the effects on C. albicans planktonic and biofilm were evaluated. After validation, OZ was included in a therapeutic protocol of denture stomatitis in vivo. Thirty patients used OZ and 20 used sodium bicarbonate (SB) for 14 days. After 7 and 14 days, clinical evaluation, isolation and identification of yeasts were performed. Isolates were identified by phenotypic and genotypic tests. Ozonated oil showed in vitro antifungal activity against all species of Candida. Ozonated oil reduced the number of viable cells in C. albicans biofilms. Oral candidal levels were lower in relation to baseline both after after 14 days of treatment with SB and OZ. Results: A total of 493 Candida spp. isolates was obtained and 80% were identified as C. albicans. Remission of denture stomatitis was observed in all patients after 7 days of treatment in both groups. Conclusion: Within the limits of the study we can conclude that ozonized olive oil can be a new alternative for the control of biofilm in patients with denture stomatitis. (AU)

Objetivo: O objetivo deste estudo foi avaliar o efeito do óleo ozonizado (OZ) sobre os níveis orais de Candida spp. em pacientes com estomatite protética. Material e Métodos: Testes in vitro foram realizados para validar a atividade antifúngica e padronizar as condições do OZ. A atividade antifúngica foi avaliada contra C. albicans e cinco espécies não-albicans (C. tropicalis, C. dubliniensis, C. krusei, C. guilliermondii e C. parapsilosis). Além disso, os efeitos sobre C. albicans planctônico e biofilme foram avaliados. Após validação, o OZ foi incluído em um protocolo terapêutico de estomatite protética in vivo. Trinta pacientes usaram OZ e 20 usaram bicarbonato de sódio (SB) por 14 dias. Após 7 e 14 dias, foram realizadas avaliações clínicas, isolamento e identificação de leveduras. Os isolados foram identificados por testes fenotípicos e genotípicos. O óleo ozonizado mostrou atividade antifúngica in vitro contra todas as espécies de Candida. O óleo ozonizado reduziu o número de células viáveis em biofilmes de C. albicans. Os níveis orais de candidíase foram menores em relação aos valores basais após 14 dias de tratamento com SB e OZ. Resultados: Um total de 493 Candida spp. isolados foram obtidos e 80% foram identificados como C. albicans. A remissão da estomatite protética foi observada em todos os pacientes após 7 dias de tratamento em ambos os grupos. Conclusão: Dentro dos limites do estudo podemos concluir que o óleo de oliva ozonizado pode ser uma nova alternativa para o controle do biofilme em pacientes com estomatite protética.(AU)

Gallic acid/hydroxypropyl-ß-cyclodextrin complex: Improving solubility for application on in vitro/ in vivo Candida albicans biofilms.

The aim of this study was to increase the solubility of gallic acid (GA) for the treatment of Candida albicans biofilm, which is very difficult to treat and requires high drug concentrations. Cyclodextrins (CDs) were used for this purpose. Complexes were evaluated by phase-solubility studies, prepared by spray drying and characterized by drug loading, scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The complexes were tested on C. albicans biofilm using in vitro and in vivo models. HPßCD formed soluble inclusion complexes with GA. The percentage of GA in GA/HPßCD was 10.8 ± 0.01%. The SEM and DSC analyses confirmed the formation of inclusion complexes. GA/HPßCD maintained the antimicrobial activity of the pure GA. GA/HPßCD was effective on C. albicans biofilms of 24 and 48h. The in vivo results showed an anti-inflammatory activity of GA/HPßCD with no difference in invading hypha counting among the groups. This study encourages the development of new antifungal agents.

Terapias alternativas para o tratamento da estomatite por prótese total: modelo experimental in vivo em ratos / Alternative therapies for denture stomatitis treatment: in vivo experimental model in rats

A estomatite por prótese (EP) é uma condição multifatorial que acomete frequentemente usuários de prótese total e geralmente é relacionada com Candida albicans. Devido aos efeitos tóxicos da terapia antifúngica, novas terapias para EP são necessárias. Objetivos: O objetivo deste estudo foi avaliar a eficácia do extrato aquoso de Buchenavia tomentosa e bicarbonato de sódio frente a C. albicans em um modelo de EP em ratos. Material e Métodos: Um aparelho de resina acrílica simulando a base da prótese total foi fixado cobrindo o palato de 48 ratos machos seguido por indução da candidose. Os ratos foram divididos em 4 grupos (n=12): controle, bicarbonato de sódio, B. tomentosa e nistatina (controle positivo). Cada grupo foi subdividido de acordo com o período de tratamento; 24 horas (n=6) e 48 horas (n=6). Os animais foram sacrificados e os aparelhos foram removidos para contagem de C. albicans e análise por microscopia eletrônica de varredura. Resultados: Após 24 horas de tratamento, observou-se redução significativa da contagem de C. albicans tanto B. tomentosa quanto nistatina (nistatina x controle, p<0,01; B. tomentosa x controle, p=0,03). Os resultados foram confirmados pela análise histológica. Conclusão: Tanto o extrato aquoso de B. tomentosa e o bicarbonato de sódio foram capazes de reduzir significativamente as contagens de C. albicans em modelo experimental de EP (AU)

Background: Denture stomatitis (DS) is a multifactorial condition that commonly affects denture users and is mainly caused by Candida albicans. Due to the toxic effects of antifungal therapy, new therapies for DS are claimed. Objective: The aim of the study was to evaluate the efficacy of aqueous extract of Buchenavia tomentosa and sodium bicarbonate against C. albicans in a model of DS in rats. Material and Methods: An acrylic resin device simulating a denture base was fixed covering the palate of forty-eight male rats followed by candidiasis induction. Rats were divided into 4 groups (n = 12): Control, sodium bicarbonate, B. tomentosa and nystatin (positive control). Each group was subdivided according to the period of treatment; 24 h (n = 6) and 48 h (n = 6). Animals were sacrificed and had their devices removed for C. albicans counts and SEM analysis. The palate mucosa was removed and processed for histopathologic analysis. Results: After 24 h of treatment, both B. tomentosa and nystatin groups reduced significantly C. albicans counts when compared to control (nystatin x control, p < 0.01; B. tomentosa x control, p = 0.03). The results were confirmed by the histologic analysis. Conclusion: Both the aqueous extract of B. tomentosa and sodium bicarbonate was able to significantly decrease C. albicans counts in an experimental model of DS (AU)

Atividade da fração enriquecida em fenólicos de Buchenavia tomentosa e de algumas substâncias isoladas antes e após encapsulação com beta-ciclodextrina em Candida albicans / Activity of phenolic enriched fraction of Buchenavia tomentosa and some isolated compounds before and after encapsulation with beta-cyclodextrin in Candida albicans

O objetivo deste estudo foi avaliar a efetividade frente a Candida albicans da fração enriquecida em fenólicos (FE) das folhas de Buchenavia tomentosa além das substâncias ácido gálico (AG), corilagina, kaempferol e vitexina, substâncias fenólicas que foram previamente detectadas no extrato aquoso de B. tomentosa livres ou encapsuladas em ciclodextrinas. Para tal, foi realizado teste de micro diluição com cepas padrão e isolados clínicos e análise química da FE por espectrometria de massa (ESI-MS).Detectou-se que o extrato acetônico foi a FE e AG foi a substância fenólica mais eficiente contra C. albicans. O efeito de FE e AG contra os fatores de virulência de C. albicans foram analisados. FE e AG foram encapsulados em 2-hidroxipropil-beta-ciclodextrina e tiveram sua análise química realizada. As CIMs e CFMs dos encapsulados foram determinadas, porém apenas o AG encapsulado teve sua ação antibiofilme e in vivo verificadas. A citotoxicidade de AG e FE livres e encapsulados foi determinada. As CIMs variaram de 5,0 e 0,625 mg/mlpara o ácido gálico e 2,5 e 0,019 mg/ml para FE. AG e as outras moléculas foram encontradas na FE. Não foram encontrados CFMs. Os fenólicos estudados também foram encontrados em FE por ESI/MS. Tanto FE quanto AG tiveram efeito direto nos fatores de virulência de C. albicans, exceto sobre a secreção de exoenzimas. Não houve diferença na CIM entre as substâncias livres e encapsuladas. AG encapsulado teve melhor ação anti-biofilme do sua forma livre. Foi verificada melhora clínica de lesões eritematosas no palato de ratos, porém não foi possível. A citotoxicidade das substâncias livres ou encapsuladas variou de moderava a leve para FE e foi moderada para AG. Após as análises, observou-se o efeito anti-C. albicans de FE e AG. AG encapsulado apresentou promissor efeito anti-biofilme e aparente melhora clínica nas lesões sugestivas de candidose eritematosa na mucosa palatar dos ratos

The aim of this study was to evaluate the effectiveness against Candida albicans of fraction enriched in phenolic (FE) of Buchenavia leavestomentosa beyond substances gallic acid (GA), corilagin, kaempferol andvitexin, phenolic substances previously detected in the aqueous extract ofB. tomentosa, free or encapsulated in cyclodextrins. Microdilution test with standard strains and clinical isolates besides the chemical analysis of FEby mass spectrometry (ESI-MS) were carried out. The acetone extract was the FE and AG was the most efficient phenolic substance against C.albicans. The effect of FE and AG against the virulence factors of C.albicans was also analyzed. FE and AG were encapsulated into 2-hydroxypropyl-beta-cyclodextrin (HP-β-CD) and had their chemical analyses made. MICs and MFCs of encapsulated have been determined.Solely the GA encapsulated had its anti-biofilm and in vivo action verified.Cytotoxicity of free and encapsulated GA and FE were determined. TheMIC ranged from 5,0 to 0,625 mg/ml for GA and 2,5 and 0,019 mg/ml forFE. MFCs values were not found. All phenolics molecules were found inFE by ESI/MS. AG and FE had a direct effect on virulence factors of C.albicans, except on the secretion of exoenzymes. There was no differencein the CIM between free and encapsulated substances. The anti-biofilm effect was better in GA encapsuladed than its free form. A clinical improvement of sugestives erythematous lesions on the palate of rats was observed, although the hyphaes were not found in the palatar mucosa.The cytotoxicity for all substances was moderated. After the analysis, weobserved the anti-C. albicans effect of GA and FE. AG encapsulated showed promising anti-biofilm effect and apparent clinical improvement inlesions suggestive of erythematous candidiasis in palatar mucosa of rats

Atividade da fração enriquecida em fenólicos de Buchenavia tomentosa e de algumas substâncias isoladas antes e após encapsulação com beta-ciclodextrina em Candida albicans / Activity of phenolic enriched fraction of Buchenavia tomentosa and some isolated compounds before and after encapsulation with beta-cyclodextrin in Candida albicans

O objetivo deste estudo foi avaliar a efetividade frente a Candida albicans da fração enriquecida em fenólicos (FE) das folhas de Buchenavia tomentosa além das substâncias ácido gálico (AG), corilagina, kaempferol e vitexina, substâncias fenólicas que foram previamente detectadas no extrato aquoso de B. tomentosa livres ou encapsuladas em ciclodextrinas. Para tal, foi realizado teste de micro diluição com cepas padrão e isolados clínicos e análise química da FE por espectrometria de massa (ESI-MS).Detectou-se que o extrato acetônico foi a FE e AG foi a substância fenólica mais eficiente contra C. albicans. O efeito de FE e AG contra os fatores de virulência de C. albicans foram analisados. FE e AG foram encapsulados em 2-hidroxipropil-beta-ciclodextrina e tiveram sua análise química realizada. As CIMs e CFMs dos encapsulados foram determinadas, porém apenas o AG encapsulado teve sua ação antibiofilme e in vivo verificadas. A citotoxicidade de AG e FE livres e encapsulados foi determinada. As CIMs variaram de 5,0 e 0,625 mg/mlpara o ácido gálico e 2,5 e 0,019 mg/ml para FE. AG e as outras moléculas foram encontradas na FE. Não foram encontrados CFMs. Os fenólicos estudados também foram encontrados em FE por ESI/MS. Tanto FE quanto AG tiveram efeito direto nos fatores de virulência de C. albicans, exceto sobre a secreção de exoenzimas. Não houve diferença na CIM entre as substâncias livres e encapsuladas. AG encapsulado teve melhor ação anti-biofilme do sua forma livre. Foi verificada melhora clínica de lesões eritematosas no palato de ratos, porém não foi possível. A citotoxicidade das substâncias livres ou encapsuladas variou de moderava a leve para FE e foi moderada para AG. Após as análises, observou-se o efeito anti-C. albicans de FE e AG. AG encapsulado apresentou promissor efeito anti-biofilme e aparente melhora clínica nas lesões sugestivas de candidose eritematosa na mucosa palatar dos ratos.

The aim of this study was to evaluate the effectiveness against Candida albicans of fraction enriched in phenolic (FE) of Buchenavia leavestomentosa beyond substances gallic acid (GA), corilagin, kaempferol andvitexin, phenolic substances previously detected in the aqueous extract ofB. tomentosa, free or encapsulated in cyclodextrins. Microdilution test with standard strains and clinical isolates besides the chemical analysis of FEby mass spectrometry (ESI-MS) were carried out. The acetone extract was the FE and AG was the most efficient phenolic substance against C.albicans. The effect of FE and AG against the virulence factors of C.albicans was also analyzed. FE and AG were encapsulated into 2-hydroxypropyl-beta-cyclodextrin (HP-β-CD) and had their chemical analyses made. MICs and MFCs of encapsulated have been determined.Solely the GA encapsulated had its anti-biofilm and in vivo action verified.Cytotoxicity of free and encapsulated GA and FE were determined. TheMIC ranged from 5,0 to 0,625 mg/ml for GA and 2,5 and 0,019 mg/ml forFE. MFCs values were not found. All phenolics molecules were found inFE by ESI/MS. AG and FE had a direct effect on virulence factors of C.albicans, except on the secretion of exoenzymes. There was no differencein the CIM between free and encapsulated substances. The anti-biofilm effect was better in GA encapsuladed than its free form. A clinical improvement of sugestives erythematous lesions on the palate of rats was observed, although the hyphaes were not found in the palatar mucosa.The cytotoxicity for all substances was moderated. After the analysis, weobserved the anti-C. albicans effect of GA and FE. AG encapsulated showed promising anti-biofilm effect and apparent clinical improvement inlesions suggestive of erythematous candidiasis in palatar mucosa of rats.

Effectiveness of 2% peracetic acid for the disinfection of gutta-percha cones.

The aim of this study was to evaluate the effectiveness of 2% peracetic acid for the disinfection of gutta-percha cones contaminated in vitro with Escherichia coli, Staphylococcus aureus, Streptococcus mutans, Candida albicans and Bacillus subtilus (in spore form). Two hundred and twenty-five gutta-percha cones were contaminated with standardized suspensions of each microorganism and incubated at 37°C for 24 h. The cones were divided into 10 experimental groups (n = 15), according to the microorganism tested and disinfection testing times. The disinfection procedure consisted of immersing each cone in a plastic tube containing the substance. The specimens remained in contact with the substance for 1 or 2.5 minutes. Afterwards, each cone was transferred to a 10% sodium thiosulphate solution (Na(2)S(2)O(3)) to neutralize the disinfectant. Microbial biofilms adhering to the cones were dispersed by agitation. Aliquots of 0.1 ml of the suspensions obtained were plated on Sabouraud dextrose agar, or brain and heart infusion agar, and incubated at 37°C for 24 h. The results were expressed in colony forming units (CFU/ml) and the data were submitted to the Wilcoxon Signed Rank Test (level of significance at 0.05). A significant reduction was observed, after 1 minute of exposure, in the test solution for C. albicans (p = 0.0190), S. aureus (p = 0.0001), S. mutans (p = 0.0001), B. subtilis (p = 0.0001), and E. coli (p = 0.0001). After 2.5 minutes of exposure, 100% of the microbial inocula were eliminated. It was concluded that the 2% peracetic acid solution was effective against the biofilms of the tested microorganisms on gutta-percha cones at 1 minute of exposure.

Effectiveness of 2 percent peracetic acid for the disinfection of gutta-percha cones

The aim of this study was to evaluate the effectiveness of 2 percent peracetic acid for the disinfection of gutta-percha cones contaminated in vitro with Escherichia coli, Staphylococcus aureus, Streptococcus mutans, Candida albicans and Bacillus subtilus (in spore form). Two hundred and twenty-five gutta-percha cones were contaminated with standardized suspensions of each microorganism and incubated at 37°C for 24 h. The cones were divided into 10 experimental groups (n = 15), according to the microorganism tested and disinfection testing times. The disinfection procedure consisted of immersing each cone in a plastic tube containing the substance. The specimens remained in contact with the substance for 1 or 2.5 minutes. Afterwards, each cone was transferred to a 10 percent sodium thiosulphate solution (Na2S2O3) to neutralize the disinfectant. Microbial biofilms adhering to the cones were dispersed by agitation. Aliquots of 0.1 ml of the suspensions obtained were plated on Sabouraud dextrose agar, or brain and heart infusion agar, and incubated at 37°C for 24 h. The results were expressed in colony forming units (CFU/ml) and the data were submitted to the Wilcoxon Signed Rank Test (level of significance at 0.05). A significant reduction was observed, after 1 minute of exposure, in the test solution for C. albicans (p = 0.0190), S. aureus (p = 0.0001), S. mutans (p = 0.0001), B. subtilis (p = 0.0001), and E. coli (p = 0.0001). After 2.5 minutes of exposure, 100 percent of the microbial inocula were eliminated. It was concluded that the 2 percent peracetic acid solution was effective against the biofilms of the tested microorganisms on gutta-percha cones at 1 minute of exposure.

Avaliação da atividade antifúngica dos extratos de buchenavia tomentosa sobre candida spp / Avaliation of antifungal activity of Buchenavia tomentosa extracts on Candida spp

O interesse pelo desenvolvimento de terapias alternativas para o controle de Candida spp., como a pesquisa de compostos naturais com potencial antifúngico, vem crescendo. Estes micro-organismos são importantes causadores de infecções e têm se tornado resistente aos antifúngicos convencionais. Desta forma, o objetivo deste estudo foi avaliar a atividade antifúngica de extratos de Buchenavia tomentosa sobre Candida spp. Inicialmente foi realizado screening por meio de teste de difusão em ágar de extratos de B. tomentosa obtidos por diferentes métodos para seleção dos dois mais ativos. A seguir, esses extratos foram caracterizados quimicamente através da técnica de espectrometria de massas por injeção direta. As concentrações inibitória mínima e fungicida mínima (CIMs e CFMs) foram determinadas para amostras padrão, isolados clínicos obtidos de pacientes com candidose bucal e cepas de origem hospitalar de Candida spp. Os resultados do screening demonstraram que os extratos aquosos B (5 minutos/100 °C) e C (60 minutos/55 °C) foram os mais ativos. As CIMs encontradas, em mg/ml, variaram de 0,2 a 25. As CFMs foram verificadas apenas paras cepas de C. krusei (3,12 a 6,25 mg/ml) e para 4 cepas de C. tropicalis (6,25 a 12,5 mg/ml). As cepas mais sensíveis aos extratos foram C. glabrata, C. dubliniensis, C. krusei e C. parapsilosis e as cepas mais resistentes foram C. albicans e C. tropicalis. O extrato B foi mais efetivo para todos os isolados, exceto para C. glabrata. O ácido gálico, corilagina e kaempferol foram encontradas apenas no extrato B. Conclui-se que, exceto os extratos A e E para C. tropicalis, todos os extratos de B. tomentosa tiveram ação antifúngica para Candida spp., sendo os extratos aquosos B e C os mais eficazes

The interest on the development of alternative therapies for Candida spp. control, as searching of natural compounds with antifungal potential, has increased. These microorganisms are important causative agents of infections and the resistance to conventional antifungals has been growing. The aim of this study was to evaluate the antifungal activity of Buchenavia tomentosa extracts on Candida spp. Screening by using agar diffusion test was performed to select two most active extracts. Then, the extracts were chemically characterized by direct infection mass spectrometry. Minimal inhibitory and fungicide concentrations (MICs and MFC) were determined for standard strains, clinical isolates from oral candidosis patients and nosocomial isolates. The findings of screening showed that aqueous extract B (5 min./100 °C) and C (60 min./55 °C) were the most active. Values of MIC found in, mg/ml, varied from 0.2 to 25. Values of MFC were observed for C. krusei (3.12 to 6.25 mg/ml) and for 4 C. tropicalis isolates (6.25 to 12.5 mg/ml). The most susceptible species were C. glabrata, C. dubliniensis, C. krusei and C. parapsilosis and the most resistant were C. albicans and C. tropicalis. Extract B was effective against all the isolates, except for C. glabrata. Galic acid, corilagin and kaempferol were found only in extract B. It could be concluded that, except extracts A and E against C. tropicalis, all extracts of B. tomentosa had antifungal activity against Candida spp. Besides, the aqueous extracts B and C were the most effective

Atividade antifúngica do óleo essencial de melaleuca alternifolia sobre leveduras isoladas de candidíase bucal de gestantes HIV positivas / Antifungal activity of melaleuca alternifolia essential oil on yeasts isolated from HIV positive pregnant women with oral candidiasis

A candidíase bucal é a infecção fúngica mais comum em portadores de HIV e, com episódios recorrentes em pacientes com Aids. Com o objetivo de pesquisar novos e eficazes agentes antifúngicos contra cepas resistentes, foi investigada a atividade antifúngica do óleo essencial de Melaleuca alternifolia, em diferentes concentrações, em leveduras isoladas de candidíase oral. O experimento foi realizado por meio da técnica de difusão em ágar. Foram avaliadas cepas padrão de Candida albicans ATCC 10231, Candida tropicalis ATCC 157, Candida glabrata ATCC 30070, Candida krusei ATCC 6258 e Candida dubliniensis ATCC 778157e os isolados da cavidade bucal de gestantes HIV positivas, sendo sete C. albicans, um C. tropicalis, um C.glabrata e um C. krusei. O óleo essencial foi analisado nas quantidades de 20 e 50 μL, nas concentrações de 10 a 100%, variando de 10 em 10%. Todas as cepas analisadas foram suscetíveis ao óleo essencial de M.alternifolia nas concentrações de 70% e 50 %, respectivamente, nos volumes de 20 μL e 50 μL. O potencial antifúngico do óleo essencial de M. alternifolia desperta interesse para o desenvolvimento de novos fármacos.

Oral candidiasis is a fungal infection mostly common in people infected with HIV and the recurrent episodes occur in patients with AIDS. Aiming at searching, a new and efficacious drug against resistant strains, the antifungal activity of essential oil from Melaleuca alternifolia at different concentrations was assessed on yeasts isolated from oral candidiasis. The experiment was performed by using agar diffusiontechnique; and the antifungal effect was evaluated on the standard strains of Candida albicans ATCC 10231, Candida tropicalis ATCC 157, Candida glabrata ATCC 30070, Candida krusei ATCC 6258 and Candida dubliniensis ATCC 778 157, and on the isolated from the oral cavity of HIV positive pregnant women, being seven C. albicans, one C. tropicalis, one C glabrata and one C. krusei. The essential oil was analyzedin quantities of 20 and 50 μL at 10-100% concentrations, ranging from 10 to 10%. All of the tested strainswere susceptible to the M. alternifolia essential oil at concentrations of 70% and 50% in volumes of 20 μL and 50 μL, respectively. The antifungal activity of essential oil from M. alternifolia holds one´s attention in manufacturing new and effective drugs.

Atividade antifúngica do óleo essencial de Cymbopogon citratus frente a cepas de Candida albicans e Candida tropicalis isoladas de infecções nosocomiais / Antifungal activity of Cymbopogon citratus essential oil on Candida albicans and Candida tropicalis strains isolated from nosocomial infections

O óleo essencial de Cymbopogon citratus tem sido alvo de vários estudos em função do potencial antimicrobiano. Neste estudo, a atividade desse componente foi investigada em cepas do gênero Candida isoladas de infecções hospitalares. Para a condução do estudo, foram analisadas 24 isolados de Candida albicans e 15 isolados de Candida tropicalis, originados de pacientes com suspeitas de infecção hospitalar e uma cepa padrão de C. albicans ATCC 10231, por meio da técnica de difusão em ágar. O óleo essencial de C. citratus apresentou atividade antifúngica em 100% dos isolados a partir da concentração de 25% (v/v), o que indica sua ação positiva sobre as cepas hospitalares. Sugere-se a realização de estudos farmacológicos e toxicológicos desse componente para avaliar a possível aplicação clínica.

Atividade antifúngica do citral em leveduras do gênero Candida isoladas de pacientes hospitalizados / Citral antifungal activity against Candida genus yeasts isolated from hospitalized patients

O citral, componente do óleo essencial de Cymbopogon citratus, tem sido pesquisado para verificar sua ação antimicrobiana em bactérias e fungos. Com o objetivo de avaliar a atividade antifúngica do citral contra leveduras do gênero Candida, no presente trabalho foram avaliadas 32 amostras de Candida albicans, 25 de C. tropicalis, 20 de C. parapsilosis e 5 de C. glabrata, coletadas de pacientes hospitalizados. O citral foi testado nas concentrações de 10%, 15%, 25%, 35%, 50% e 60% (v/v), utilizando a técnica de difusão em ágar Sabouraud. A atividade antifúngica do citral foi constatada em todas as leveduras selecionadas nas concentrações ≥25%. Mediante os resultados obtidos, sugere-se a realização de novas pesquisas sobre citral frente às demais espécies de fungos patogênicos para conhecer as características toxicológicas e farmacológicas para que esse componente possa futuramente ser utilizado como um importante princípio ativo na produção de novos agentes antifúngicos.