Antimicrobial activity of the edible mushroom Pleurotus eryngii(DC. ) Quél grown in liquid medium

Edible mushrooms have a number of medicinal properties and this study aimed to investigate the antimicrobial activity of Pleurotus eryngiiDPUA1816 in metabolic broths after being grown in submerged cultivation. Mycelial fragments of pure P. eryngiiculture was inoculated in sweet potato culture medium and incubated at 150 rpm for 15 days at 25°C. Pleurotuseryngiiwas also cultivated for 18 days under the same conditions, the mycelial biomass was separated by filtration for quantification. The supernatant was used in the diffusion test in agar and performed against Escherichia coliCCCD-E005, Staphylococcus aureus CCCD-S009, Pseudomonas aeruginosaCCCD-P004, Candida albicansCCCD-CC001, Candida parapsilosis CCCD-CC004 and Candida tropicalisCCCD-CC002. The samples showed no inhibitory activity against bacteria, however they showed some activity againstC. albicans(12.17 mm), C. parapsilosis(27.67 mm) and C. tropicalis(13.67 mm). After being cultivated for 18 days, P. eryngiiwas able to inhibit all yeasts after 12 days of culture, with an inhibition halo of 29.33 mm at 16 days against C. parapsilosis. This study demonstrates the antifungal potential filtered liquids from P.eryngiicultivated in purple-skinned sweet potato culture medium, which suggests the possibility of the use of this species by the pharmaceutical industry as a natural source of biological action.

Antimicrobial activity of the edible mushroom Pleurotus eryngii(DC. ) Quél grown in liquid medium

Edible mushrooms have a number of medicinal properties and this study aimed to investigate the antimicrobial activity of Pleurotus eryngiiDPUA1816 in metabolic broths after being grown in submerged cultivation. Mycelial fragments of pure P. eryngiiculture was inoculated in sweet potato culture medium and incubated at 150 rpm for 15 days at 25°C. Pleurotuseryngiiwas also cultivated for 18 days under the same conditions, the mycelial biomass was separated by filtration for quantification. The supernatant was used in the diffusion test in agar and performed against Escherichia coliCCCD-E005, Staphylococcus aureus CCCD-S009, Pseudomonas aeruginosaCCCD-P004, Candida albicansCCCD-CC001, Candida parapsilosis CCCD-CC004 and Candida tropicalisCCCD-CC002. The samples showed no inhibitory activity against bacteria, however they showed some activity againstC. albicans(12.17 mm), C. parapsilosis(27.67 mm) and C. tropicalis(13.67 mm). After being cultivated for 18 days, P. eryngiiwas able to inhibit all yeasts after 12 days of culture, with an inhibition halo of 29.33 mm at 16 days against C. parapsilosis. This study demonstrates the antifungal potential filtered liquids from P.eryngiicultivated in purple-skinned sweet potato culture medium, which suggests the possibility of the use of this species by the pharmaceutical industry as a natural source of biological action.(AU)

Nitrogen source and pH interact and modulate lipase secretion in a non-clinical strain of Candida parapsilosis

Lipases (E.C. 3.1.1.3) are serine-hydrolases, and act on long chain fatty acid ester bonds. They exhibit specific and enantioselective activities, which are desirable for many industrial applications. This study aimed at screening and optimizing the production of lipases by wild yeast strains from a variety of substrates, as well as characterizing the enzyme. An initial selection was made in oxygenated oil-supplemented minimum medium, and the enzymatic activity of the supernatant was tested over p-nitrophenyl palmitate. One-hundred and twenty-four yeast strains from different substrates were tested, and twenty-three showed significantly higher lipolytic activity (p<0.01). One yeast in particular, QU110, showed best lipase production and therefore was selected for the optimization and characterization processes. This yeast exhibits enzyme secretion in initial pH 6.0, with olive oil and tryptone as carbon and nitrogen sources, respectively. There was a strong interaction between nitrogen source and initial pH, and pH 9.0seems to inhibit enzyme secretion. The crude enzyme (cell-free supernatant) shows stability in surfactants and n-hexane, but not in ethanol or methanol. A Response Surface Model was created and optimal enzyme activity conditions were observed at 36°C and pH 8.0. The lipase is appropriate for transesterification reactions, as the enzyme is more stable in strong apolar solvents than moderately apolar ones. Also, secretion by pH was not reported elsewhere, which should be further investigated and contribute for other yeast bioprocesses as well.

Occurrence of Candida orthopsilosis in Brazilian tomato fruits (Lycopersicum esculentum Mill)

We aimed to isolate and identify yeasts found in the tomato fruit in order to obtain isolates with biotechnological potential, such as in control of fungal diseases that damage postharvest fruits. We identified Candida orthopsilosis strains LT18 and LT24. This is the first report of this yeast on Lycopersicum esculentum fruits in Brazil.

Occurrence of Candida orthopsilosis in Brazilian tomato fruits (Lycopersicum esculentum Mill)

We aimed to isolate and identify yeasts found in the tomato fruit in order to obtain isolates with biotechnological potential, such as in control of fungal diseases that damage postharvest fruits. We identified Candida orthopsilosis strains LT18 and LT24. This is the first report of this yeast on Lycopersicum esculentum fruits in Brazil.(AU)

O COMPLEXO Candida parapsilosis: UMA ABORDAGEM DAS ESTRATÉGIAS DE IDENTIFICAÇÃO, CINÉTICA DE CRESCIMENTO, VIRULÊNCIA E SENSIBILIDADE ANTIFÚNGICA

A heterogeneidade genética de Candida parapsilosis ocasionou a sua reclassificação taxonômica em Complexo C. parapsilosis, composto por C. parapsilosis sensu stricto, C. orthopsilosis e C. metapsilosis, cujas diferenças biológicas estão sendo elucidadas. O objetivo desse estudo foi caracterizar o Complexo C. parapsilosis abordando as estratégica de identificação fenotípica, cinética de crescimento, os atributos de virulência e a sensibilidade aos antifúngicos clássicos e aos flavonoides kaempferol e quercetina. No primeiro momento, cepas foram submetidas a testes fenotípicos para triagem à identificação molecular das espécies crípticas; no segundo momento, a cinética de crescimento das espécies foi avaliada em diferentes condições de salinidade e pH. No terceiro momento, a produção de fatores de virulência, a patogenicidade e a sensibilidade aos antifúngicos clássicos, foram analisados. Por fim, as atividades antifúngica e antibiofilme dos flavonoides foram investigadas. Como resultados, os métodos fenotípicos são concordantes (>80%) com a identificação molecular do Complexo C. parapsilosis, e o crescimento de C. orthopsilosis foi reduzido na presença de 15% de NaCl ou pH 7,0. Além disso, foram observados elevados valores de concentração inibitória mínima (CIM) para azóis e caspofungina (CAS) contra C. orthopsilosis, e para azóis contra C. metapsilosis. A anfotericina B e a CAS causaram maior redução da atividade metabólica e da biomassa dos biofilmes maduros. Todas as três espécies produziram fosfolipases, proteases, hemolisinas e biofilme, e um aumento da taxa de mortalidade de Caenorhabditis elegans. Finalmente, os valores de CIM para kaempferol (32-128g/mL) e quercetina (0,5-16g/mL) foram encontrados. No biofilme em formação, os flavonoides reduziram a atividade metabólica das espécies. No biofilme maduro, o kaempferol aumentou a atividade metabólica de C. parapsilosis sensu stricto e C. orthopsilosis, mas reduziu a biomassa de C. orthopsilosis e C. metapsilosis, e a quercetina apenas aumentou a atividade metabólica de C. parapsilosis sensu stricto. A microscopia mostrou uma reestruturação dos biofilmes após exposição aos flavonoides. Os achados reforçam a heterogeneidade das espécies quanto às características fenotípicas, e às caracteríscticas de sensibilidade antifúngica e patogenicidade, enfatizando a relevância do monitoramento desses patógenos. Ademais, os efeitos dos flavonoides reiteram o potencial uso dos recursos naturais como ferramentas sutentáveis a serem aplicadas nas áreas da ciências médica e veterinária.

The genetic heterogeneity of the Candida parapsilosis caused the taxonomic reclassification in C. parapsilosis complex, composed by C. parapsilosis sensu stricto, C. orthopsilosis and C. metapsilosis, whose biological differences that are being elucidated. This study aimed to characterize the C. parapsilosis complex by means of approaching the phenotipical identification strategies, growth kinetics differences, virulence attributes and susceptibility to classical antifungals and flavonoids kaempferol and quercetin. At first, strains were phenotypically screened for identification of cryptic species by molecular identification; and then, the growth kinetics of the species were evaluated in hypersaline and pH media. At a third time, a production of virulence factors, phatogenicity and antifungal susceptibility were analyzed. Finally, the antifungal and antibiofilm of flavonoids were investigated. The phenotypic methods were agreement (>80%) with the molecular identification of cryptic species, and the C. orthopsilosis growth at 15% NaCl or pH 7.0 medium was reduced. In addition, minimal inhibitory concentration (MIC) values of azole and caspofungin (CAS) were found to C. orthopsilosis and of azole against C. metapsilosis. The amphotericin and CAS caused descrease the metabolic activity and biomass of mature biofilms. All cryptic species produced phospholipases, proteases, hemolysins and biofilm, and high mortality of Caenorhabditis elegans were observed. Finally, the MIC values of kaempferol (32-128 g/mL) and quercetin (0.5-16 g/mL) were found. The flavonoids descreased the metabolic activity of growing biofilms of the species. As for mature biofilms, kaempferol increased the metabolic activity of C. parapsilosis sensu stricto and C. orthopsilosis, but reduced the metabolism and biomass of C. orthopsilosis and C. metapsilosis. Quercetin, in turn, only increased the metabolic activity of C. parapsilosis sensu stricto. The microscopic analyses showed restructuring of the cryptic species biofilm after flavonoids exposure. The results reinforce the heterogeneity of these cryptic species for their phenotypic characteristics, antifungal susceptibility, virulence and pathogenicity potential, and emphasize the relevance of monitoring these emerging pathogens. In addition, the effects of flavonoids highlight the potential use of natural resources as tools to be applied for medical and veterinary sciences.

IDENTIFICAÇÃO, SENSIBILIDADE ANTIFÚNGICA, FATORES DE VIRULÊNCIA E PATOGENICIDADE DE LEVEDURAS DA MICROBIOTA DE RÉPTEIS E ANFÍBIOS

Estudos relataram infecções fúngicas em répteis e anfíbios, bem como concentrações inibitórias mínimas (CIMs) elevadas de drogas antifúngicas contra leveduras isoladas desses animais. Fatores de virulência já foram associados à patogenicidade dessas leveduras. O objetivo inicial deste estudo foi identificar leveduras isoladas de répteis e anfíbios silvestres do bioma Caatinga. Após, a produção de fosfolipases, proteases e formação de biofilme por estes fungos, bem como a sensibilidade aos antifúngicos em células planctônicas e biofilmes, foram avaliadas. Por fim, a patogenicidade in vivo de Candida famata foi investigada em Caenorhabditis elegans. Trinta e cinco leveduras dos gêneros Candida, Cryptococcus, Trichosporon e Rhodotorula foram utilizadas. Todas as cepas foram submetidas a testes bioquímicos e morfológicos para identificação. Leveduras do complexo C. parapsilosis e C. famata foram submetidas à identificação molecular. A produção de enzimas hidrolíticas e a formação de biofilme de fungos foram avaliadas. Além disso, fluconazol, itraconazol, voriconazol e anfotericina B foram utilizados para o teste de sensibilidade antifúngica. Para a sensibilidade ao biofilme, foram utilizados itraconazol e anfotericina B. A patogenicidade de C. famata contra C. elegans foi avaliada. C. famata foi a levedura mais prevalente na microbiota de répteis e anfíbios. 94% das cepas testadas foram capazes de produzir as enzimas fosfolipases e proteases e 100% das leveduras avaliadas tiveram a capacidade de formar biofilmes. C. famata e C. tropicalis apresentaram altas CIMs para fluconazol e itraconazol. Anfotericina B induziu maior redução na atividade metabólica e biomassa de biofilmes maduros. C. famata causou mortalidade de C. elegans após 96 horas de exposição. Répteis e anfíbios abrigam leveduras capazes de produzir fatores de virulência em sua microbiota. Além disso, C. famata demonstrou a capacidade de infectar C. elegans. Esses dados indicam que mais pesquisas precisam ser feitas sobre a microbiota de répteis para anfíbios.

Studies have reported fungal infections in reptiles and amphibians, as well as elevated minimum inhibitory concentrations (MICs) of antifungal drugs to yeasts isolated from these animals. Virulence factors have been associated with the pathogenicity of these yeasts. The initial aim of this study was to identify yeasts isolated from wild reptiles and amphibians from the Caatinga biome. Next, the production of phospholipases, proteases and biofilm formation by these fungi, as well as susceptibility to antifungals in planktonic cells and biofilms, were evaluated. Finally, in vivo pathogenicity of Candida famata was investigated in Caenorhabditis elegans. Thirty-five yeasts of the genera Candida, Cryptococcus, Trichosporon and Rhodotorula were used. All strains were submitted to biochemical and morphological tests for identification. Yeasts of the C. parapsilosis complex and C. famata were submitted to molecular identification. The production of hydrolytic enzymes and biofilm formation of fungi were evaluated. In addition, fluconazole, itraconazole, voriconazole and amphotericin B were used for antifungal susceptibility testing. For biofilm susceptibility, itraconazole and amphotericin B were used. The pathogenicity of C. famata against Caenorhabditis elegans was evaluated. C. famata was the most prevalent yeast in the reptile and amphibian microbiota. 94% of the strains tested were capable of producing phospholipase and protease enzymes and 100% of the yeasts evaluated had the ability to form biofilms. C. famata and C. tropicalis showed high MICs to fluconazole and itraconazole. Amphotericin B induced greater reduction in the metabolic activity and biomass of mature biofilms. C. famata caused mortality of C. elegans after 96 hours of exposure. Reptiles and amphibians were colonized by yeasts able to produce virulence factors in their microbiota. In addition, C. famata demonstrated the ability to infect C. elegans. These data indicate that more research needs to done on the microbiota of reptiles to amphibians.

Pericardite bacteriana com subsequente desenvolvimento de endocardite mural por levedura do complexo Candida parapsilosis / Bacterial pericarditis with subsequent development of mural endocarditis caused by Candida parapsilosis complex yeast

A infecção primária do pericárdio e do endocárdio é rara. Este estudo descreve a evolução de uma criança com cardite reumática aguda, complicada com pericardite infecciosa bacteriana, secundária a abscessos de pele e endocardite fúngica. O tempo prolongado de internação, o uso de cateter venoso central e a antibioticoterapia de amplo espectro foram os fatores que provavelmente favoreceram a colonização, a candidíase invasiva e o desenvolvimento da endocardite por levedura do complexo Candida parapsilosis.(AU)

The primary infection of pericardium and endocardium rarely occurs. This study reports the evolution of a child with acute rheumatic carditis with subsequent pericardial bacterial infection, due to cutaneous abscess and fungal endocarditis. Probably, the long hospital stay, the usage of central venous catheter and the broad-spectrum antibiotics enhanced the colonization, the invasive candidiasis induction and the development of fungal endocarditis by Candida parapsilosis complex yeast.(AU)

Contaminação fúngica no leite humano e em sítios anatômicos de lactantes e lactentes / Fungal contamination in human milk and in the anatomic sites of breastfeeding mothers and infants

As infecções bacterianas ou fúngicas causam quadro clínico de mastite, que motiva desmame precoce. Os micro-organismos patogênicos, como leveduras do gênero Candida , quando em número elevado no intestino, podem causar disbiose. Nesta pesquisa, foram realizadas a detecção e a identificação de microbiota fúngica nas amostras de leite humano e de sítios anatômicos de mulheres e crianças atendidas pelo Banco de Leite Humano do Instituto Fernandes Figueira. A virulência dos isolados de levedura foi determinada pelos testes de atividade proteolítica. De 64 amostras analisadas, 81% foram positivas para fungos, com maior prevalência de Candida albicans (73%), seguida do complexo C. parapsilosis (15,4%). Perfis semelhantes aos verificados no total de amostras foram encontrados nas amostras de leite, nas mamas e na cavidade oral, sugerindo-se a ocorrência de associação entre a infecção cutânea da mãe e do lactente com o leite ingerido. O perfil associado à virulência dos isolados de Candida foi determinado pelo teste de produção de proteases, e 100% das amostras mostraram resultados fortemente positivos, indicando alto grau de infecciosidade . A alta prevalência de C. albicans nas amostras coletadas de mamas, no leite e na cavidade oral, é importante fator de risco à saúde de lactentes.(AU)

Bacterial or fungal infections might produce a clinical feature of mastitis, which is one of the main causes of precocious breast-feeding discontinuity. In addition, when the potentially pathogenic microorganisms as yeast of Candida genera were in high counting in the intestine, might cause dysbiosis. This study aimed detecting and identifying fungi in human milk and anatomical sites of breast-feeding women and infants who were enrolled at Human Milk Bank of the Institute Fernandes Figueira. The virulence of the yeast isolates was evaluated by means of proteolytic activity tests. Eight-one percent of 64 analyzed samples showed positive results to fungi, with a highest prevalence of Candida albicans (73%) followed by C. parapsilosis complex (15.4%). Similar profiles were found in samples of milk, of breasts and of infants mouth cavity, suggesting a correlation between breast-feeding mothers and infants cutaneous infections with the ingested milk. The virulence of the isolated Candida was determined by the proteolytic activity test. All of the isolates (100%) were strongly positive, indicating a high degree of infectivity. The high prevalence of C. albicans in samples collected from breasts, mouth cavity and milk is a crucial risk factor for the infants health.(AU)

INCIDÊNCIA E FATORES PREDITORES PARA CANDIDEMIA EM PACIENTES INTERNADOS EM UNIDADES DE TERAPIA INTENSIVA DE HOSPITAL TERCIÁRIO NA REGIÃO CENTRO-OESTE DO BRASIL

Candidemia, uma frequente infecção hospitalar de corrente sanguínea, aumenta o tempo de internação, eleva os custos hospitalares e aumenta o número de óbitos. Realizou-se uma coorte com pacientes internados em unidades de terapia intensiva adulto e neonatal entre 2014-2016 para avaliar o risco para desenvolver candidemia e seus fatores predisponentes. Após o seguimento de 44405 pacientes-dia observou-se o desenvolvimento de 36 casos de candidemia, sendo 17 em UTI neonatal e 19 em UTI adulto. O principal agente etiológico de candidemia em pacientes internados na UTI neonatal foi o complexo C. parapsilosis e em UTI adulto foi C. albicans. A incidência de candidemia foi estatisticamente semelhante entre as UTIs, mas a proporção de óbitos por candidemia foi estatisticamente maior entre pacientes internados na UTI neonatal. Após ajuste por outras variáveis, tempo de internação por mais de 20 dias (RR=11,18; IC95%=3,34-37,40), antibioticoterapia com glicopeptídeos concomitante com nutrição parenteral (RR=30,85; IC95%=4,70-202,65) e uso de fluconazol por mais de 10 dias (RR=0,21; IC95%=0,10-0,48) se comportaram como fatores preditores para desenvolver candidemia. O risco de candidemia foi semelhante entre UTI adulto e neonatal, diferente entre as espécies do gênero Candida e maior entre os pacientes que desenvolveram candidúria. Poucos estudos epidemiológicos sobre candidemia avaliaram esse desfecho por meio de coortes, destes, alguns realizaram análise de sobrevida (tempo entre o diagnóstico e o óbito), porém a avaliação do risco para desenvolver candidemia, ou seja, os fatores predisponentes envolvidos no tempo entre a internação e o seu diagnóstico, pode auxiliar na melhor compreensão desta importante infecção.

não consta

Antifungal activity of 2-chloro-N-phenylacetamide: a new molecule with fungicidal and antibiofilm activity against fluconazole-resistant Candida spp / Atividade antifúngica de 2-cloro-N-fenilacetamida: uma nova molécula com atividade fungicida e anti-biofilme contra Candida spp. resistentes a fluconazol

In the current context of emerging drug-resistant fungal pathogens such as Candida albicans and Candida parapsilosis, discovery of new antifungal agents is an urgent matter. This research aimed to evaluate the antifungal potential of 2-chloro-N-phenylacetamide against fluconazole-resistant clinical strains of C. albicans and C. parapsilosis. The antifungal activity of 2-chloro-N-phenylacetamide was evaluated in vitro by the determination of the minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), inhibition of biofilm formation and its rupture, sorbitol and ergosterol assays, and association between this molecule and common antifungal drugs, amphotericin B and fluconazole. The test product inhibited all strains of C. albicans and C. parapsilosis, with a MIC ranging from 128 to 256 µg.mL-1, and a MFC of 512-1,024 µg.mL-1. It also inhibited up to 92% of biofilm formation and rupture of up to 87% of preformed biofilm. 2-chloro-N-phenylacetamide did not promote antifungal activity through binding to cellular membrane ergosterol nor it damages the fungal cell wall. Antagonism was observed when combining this substance with amphotericin B and fluconazole. The substance exhibited significant antifungal activity by inhibiting both planktonic cells and biofilm of fluconazole-resistant strains. Its combination with other antifungals should be avoided and its mechanism of action remains to be established.

No atual contexto de patógenos fúngicos resistentes emergentes tais como Candida albicans e Candida parapsilosis, a descoberta de novos agentes antifúngicos é uma questão urgente. Esta pesquisa teve como objetivo avaliar o potencial antifúngico da 2-cloro-N-fenilacetamida contra cepas clínicas de C. albicans e C. parapsilosis resistentes a fluconazol. A atividade antifúngica da substância foi avaliada in vitro através da determinação da concentração inibitória mínima (CIM), concentração fungicida mínima (CFM), ruptura e inibição da formação de biofilme, ensaios de sorbitol e ergosterol, e associação entre esta molécula e antifúngicos comuns, anfotericina B e fluconazol. O produto teste inibiu todas as cepas de C. albicans e C. parapsilosis, com uma CIM variando de 128 a 256 µg.mL-1, e uma CFM de 512-1,024 µg.mL-1. Também inibiu até 92% da formação de biofilme e causou a ruptura de até 87% de biofilme pré-formado. A 2-cloro-N-fenilacetamida não promoveu atividade antifúngica pela ligação ao ergosterol da membrana celular fúngica, tampouco danificou a parede celular. Antagonismo foi observado ao combinar esta substância com anfotericina B e fluconazol. A substância exibiu atividade antifúngica significativa ao inibir tanto as células planctônicas quanto o biofilme das cepas resistentes ao fluconazol. Sua combinação com outros antifúngicos deve ser evitada e seu mecanismo de ação deve ser estabelecido.