Isolamento de leveduras patogênicas da microbiota superficial de tamanduás mantidos em cativeiro

A composição da microbiota fúngica do pelame de animais silvestres ainda é pouco conhecida. Estabelecer parâmetros microbiológicos que permitam prever eventos infecciosos oportunistas nesses animais pode ser útil na preservação de espécies amaçadas de extinção. O objetivo dessa investigação foi isolar e identificar leveduras de potencial patogênico do pelame de tamanduás mantidos em cativeiro. Vinte e sete tamanduás, provenientes da Fundação Parque Zoológico de São Paulo (FPZSP) e Parque Municipal Quinzinho de Barros (Zôo-Sorocaba, SP) foram pesquisados. Catorze espécimes serão de tamanduá-bandeira (Mymercophaga tridactyla) e 13 de tamanduá-mirim (Tamandua tetradactyla), dos quais, 63% machos e 37%, fêmeas. A técnica do quadrado do carpete foi empregada na obtenção das amostras de pelame. As leveduras isoladas foram identificadas por meio de suas características morfológicas e por método semi-automatizado ID-32CÒ. Para descrever as variáveis obtidas por meio do instrumento de pesquisa, foram verificadas a frequência de ocorrência e os resultados foram expressos em valores relativos. Foram isoladas, no total, 33 leveduras a partir das amostras de pelame dos 27 tamanduás. As espécies de leveduras isoladas foram: oito Candida guilliermondii (24,2%), três C. famata (9,1%), três C. kefyr (9,1%), duas C. glabrata (6,1%), três Cryptococcus laurentii (9,1%), um C. humicola (3,0%), seis Geotrichum candidum (18,2%), três Malassezia pachydermatis (9.1%), duas Rhodotorula glutinis (6,1%) e dois Trichosporon asahii (6,1%). Pode-se concluir que leveduras reconhecidamente patogênicas podem colonizar a microbiota do tegumento de tamanduás-bandeira e tamanduás-mirim mantidos em cativeiro e representam potencial risco de infecção oportunista para esses animais.

Diversidade da microbiota de fungos da própolis in natura / Diversity of in natura propolis fungal microbiota

O presente estudo teve por objetivo realizar a identificação dos fungos encontrados na própolis produzido por Apis mellifera L. da Baía do Iguape, Brasil. Para tanto, foram utilizadas técnicas morfológicas, bioquímicas e moleculares, sendo averiguado o perfil de restrição gerado por espaçador interno transcrito (ITS1 e ITS4). O tamanho dos produtos de PCR foi analisado quanto ao perfil de restrição obtidos com endonuclease (HhaI, HaeIII e HinfI) por espécie. Foram identificadas dezesseis espécies de fungos filamentosos: Flavodon flavus, Aspergillus nomius, Aspergillus versicolor, Cladosporium sp., Coniothyrium sidae, Didymella sp., Paecilomyces variotii, Cladosporium cladosporioides, Penicillium citrinum, Fusarium incarnatum, Penicillium chermesinum, Phoma sp., Stagonosporopsis valerianellae, Phoma medicaginis, Paraphoma fimeti e Stagonosporopsis cucurbitacearum; e seis espécies de leveduras: Candida tropicalis, Candida guiliermondii, Candida famata, Kodomala ohmeri, Trichosporon asahiu e Cryptococcus laurentii. Stagonosporopsis cucurbitacearum e leveduras pertencentes ao gênero Candida foram os microrganismos de maior ocorrência nas amostras da própolis provenientes da Baía do Iguape, Brasil.

Multi-mycotoxins and Fungal Contaminants of Wheat from Anambra State, Nigeria

This study was carried out to determine the fungal and mycotoxins contamination of 36 Wheat (Triticum aestivium) samples purchased randomly from the seller of the agricultural produce in local markets of Anambra State, Nigeria. Results from the studies showed that two hundred and three fungal isolates consisting of 18 species of moulds and 5 species of yeasts contaminated the wheat samples at varying degrees. For moulds, Aspergillus species contaminated the samples mostly with (28) isolates followed by Penicillum species (19) isolates while Verticillium species and Cladosporium species had equal least contaminations with (3) isolates each. Among the yeast species, Candida rugosahad the highest number of contamination with (37) isolates followed by Cryptococcus laurentii (31) isolates while Candida stellatoides (9) isolates had the least contamination. Twenty-four fungal metabolites were also recovered. The concentration of trichothecene mycotoxin Deoxynivalenol (2067µg/kg), a protein synthesis and cell proliferation inhibitor in animals exceeded the maximum acceptable limits for human consumption. It can be deduced therefore that wheat circulating in Anambra State, Nigeria are variously contaminated with different xerophilic moulds and mycotoxins which can exert adverse health problems to consumers. Keyword: Wheat samples, fungal contaminants, multi-mycotoxins and market zones

Cutinase-like biodegradable plastic-degrading enzymes from phylloplane yeasts have cutinase activity

Phylloplane yeast genera Pseudozyma and Cryptococcus secrete biodegradable plastic (BP)-degrading enzymes, termed cutinase-like enzymes (CLEs). Although, CLEs contain highly conserved catalytic sites, the whole protein exhibits ≤ 30% amino acid sequence homology with cutinase. In this study, we analyzed whether CLEs exhibit cutinase activity. Seventeen Cryptococcus magnus strains, which degrade BP at 15 °C, were isolated from leaves, and identified the DNA sequence of the CLE in one of the strains. Cutin was prepared from tomato leaves and treated with CLEs from three Cryptococcus species (C. magnus, Cryptococcus flavus, and Cryptococcus laurentii) and Pseudozyma antarctia (PaE). A typical cutin monomer, 10,16-dihydroxyhexadecanoic acid, was detected in extracts of the reaction solution via gas chromatography-mass spectrometry, showing that cutin was indeed degraded by CLEs. In addition to the aforementioned monomer, separation analysis via thin-layer chromatography detected high-molecular-weight products resulting from the breakdown of cutin by PaE, indicating that PaE acts as an endo-type enzyme.

LEVEDURAS EM CASOS DE MASTITE BOVINA SUBCLÍNICA NO SUL DO RIO GRANDE DO SUL

Alguns alimentos como o leite tem um importante papel na dieta humana, pois fornece uma série de nutrientes essenciais. A contaminação do leite por micro-organismos indesejáveis, como os fungos, pode causar alterações físico-químicas no mesmo, limitando sua durabilidade e de seus derivados, além de determinar problemas econômicos e de saúde pública. As leveduras são os agentes fúngicos mais frequentemente relacionados às infecções da glândula mamária em bovinos de leite. Para realização deste trabalho, foram coletadas 640 amostras de leite, oriundas dos quartos mamários de vacas em lactação que apresentaram resultado positivos ao Califórnia Mastitis Test (CMT). Previamente foi realizada a desinfecção do teto com algodão embebido em álcool 70ºGL e posteriormente retirou-se as amostras de aproximadamente 10 mL de leite que foram encaminhadas para o Laboratório de Micologia, no Instituto de Biologia da UFPel, semeadas em placas de Petri contendo Ágar Sabouraud Dextrose adicionado de Cloranfenicol e armazenadas na estufa por 7 dias a 36 °C. Nas amostras em que houve crescimento leveduriforme, fez-se a identificação através do Sistema Vitek 2. Foram identificados: Cryptococcus laurentii, Candida famata e Candida parapsilosis.

A Study of the Disruptive Effect of the Acetate Fraction of Punica granatum Extract on Cryptococcus Biofilms

Cryptococcosis, caused by yeasts of the genus Cryptococcus, is an infectious disease with a worldwide distribution. Cryptococcus neoformans and Cryptococcus gattii are the species that commonly cause this disease in humans; however, infections caused by Cryptococcus laurentii, especially in immunocompromised patients, are increasingly being reported. Owing to the increase in the resistance of fungi to antifungals, and a lack of treatment options, it is important to seek new therapeutic alternatives such as natural products. Among these are plant species such as Punica granatum, which is used in folk medicine to treat various diseases. This study aimed to evaluate the activity of the acetate fraction of P. granatum leaf extract against environmental and clinical isolates of Cryptococcus. Three environmental isolates of C. laurentii, PMN, PMA, and PJL II, isolated from soils of different municipalities in the state of Maranhão, a clinical isolate, C. gattii, from a patient with neurocryptococcosis, and a standard strain of C. gattii (ATCC 32068) were used. The minimum and fractional inhibitory concentrations (MIC and FIC, respectively) and time-kill curve of the extract and fluconazole were determined to assess the susceptibility profile of the fungal isolates. Larvae of Tenebrio molitor were infected with Cryptococcus strains, and the effects of acetate fraction of P. granatum extract and fluconazole on the survival and fungal burden were determined. The extract activity was tested against pre-formed biofilms. The acetate fraction of P. granatum extract showed promising antifungal activity against all the species of Cryptococcus evaluated in this study, with an MIC value lower than that of fluconazole. The indices obtained in the FIC test indicated that the antimicrobial effect of the combination of the extract and antifungal was indifferent for 80% of the isolates. The P. granatum acetate fraction reduced the pre-formed biofilm of some isolates, showing better activity than fluconazole, which is consistent with results from fluorescence microscopy. This is the first study on the use of P. granatum and its ability to inhibit Cryptococcus biofilms; therefore, further studies and tests are needed to investigate the components and mechanism of action of P. granatum against cryptococcosis agents.