Crescimentos de fungos produtores de micotoxinas em grãos de amendoim / Growths of mycotoxin-producing fungi on peanut grains

O amendoim (Arachis hypogaea L.) é uma oleaginosa com alto valor energético e nutricional, servindo de substrato ideal para o crescimento de fungos durante o processo de colheita, estocagem e processamento dos grãos. As micotoxinas são originadas a partir do metabolismo secundário de fungos toxigênicos; quando essas toxinas são ingeridas, podem causar efeitos tóxicos em humanos e animais. O objetivo deste trabalho foi avaliar a contaminação fúngica em amostras de grãos de amendoim disponíveis para o consumo humano. Foram analisadas amostras de amendoim torrado na vagem, amendoim cru (in natura) e amendoim torrado sem a vagem. A metodologia utilizada foi o método de plaqueamento direto em placas de Petri, contendo o meio cultura Sabouraud Dextrose Ágar (SDA). Porções de 40 grãos de amendoim de cada amostra foram utilizadas para o teste. Os resultados obtidos foram expressos em quantidade de grãos que apresentaram crescimento fúngico em porcentagem. Para identificação ao nível do género das colônias fúngicas isoladas, foi efetuada uma observação microscópica das suas estruturas morfológicas. Em todas as amostras estudadas ocorreram o crescimento de fungos potencialmente micotoxigênicos. Os grãos de amendoim cru (in natura) sem a vagem foram os mais contaminados por fungos como Aspergillus sp. (20%), Alternaria sp. (13,1%), Penicillium sp. (13,3%) e Fusarium sp. (23,3%) quando comparados com os grãos torrados. A presença desses fungos nas amostras de amendoim indica a possibilidade de desenvolvimento de micotoxinas potencialmente tóxicas para o humano. O processo de torrefação inibe o crescimento de determinadas espécies de fungos micotoxigênicos.(AU)

Peanut is an oilseed with high energy and nutritional value, serving as an ideal substrate for the growth of fungi during the process of harvesting, storing and processing the grains. Mycotoxins originate from the secondary metabolism of toxigenic fungi; when ingested, they can cause toxic effects in humans and animals. The objective of this work was to evaluate the fungal contamination in samples of peanut grains available for human consumption. The methodology used was the direct plating method in Petri dishes containing Sabouraud Dextrose Agar (SDA) culture. Portions of 40 peanut kernels from the samples were immersed in a 0.4% sodium hypochlorite solution for two minutes for surface disinfection, then rinsed once in distilled water. Incubation was carried out at room temperature for 7 days and the results were expressed as the amount of grains that showed fungal growth in percentage. To identify the colonies of isolated filamentous fungi at the genus level, a microscopic observation of their morphological structures was carried out, which consists of removing a sample from the edge of the colony and placing it in a drop of cotton blue (1g/L in lactic acid 88%), between slide and coverslip. Potentially toxigenic fungi were identified: Aspergillus sp., Rhizopus sp., Alternaria sp., Penicillium sp. and Fusarium sp. The presence of these fungi in peanut samples indicates the possibility of development of mycotoxins potentially toxic to humans. The roasting process may not be sufficient to destroy some mycotoxins.(AU)

Genomic prediction of leaf rust resistance to Arabica coffee using machine learning algorithms

Genomic selection (GS) emphasizes the simultaneous prediction of the genetic effects of thousands of scattered markers over the genome. Several statistical methodologies have been used in GS for the prediction of genetic merit. In general, such methodologies require certain assumptions about the data, such as the normality of the distribution of phenotypic values. To circumvent the non-normality of phenotypic values, the literature suggests the use of Bayesian Generalized Linear Regression (GBLASSO). Another alternative is the models based on machine learning, represented by methodologies such as Artificial Neural Networks (ANN), Decision Trees (DT) and related possible refinements such as Bagging, Random Forest and Boosting. This study aimed to use DT and its refinements for predicting resistance to orange rust in Arabica coffee. Additionally, DT and its refinements were used to identify the importance of markers related to the characteristic of interest. The results were compared with those from GBLASSO and ANN. Data on coffee rust resistance of 245 Arabica coffee plants genotyped for 137 markers were used. The DT refinements presented equal or inferior values of Apparent Error Rate compared to those obtained by DT, GBLASSO, and ANN. Moreover, DT refinements were able to identify important markers for the characteristic of interest. Out of 14 of the most important markers analyzed in each methodology, 9.3 markers on average were in regions of quantitative trait loci (QTLs) related to resistance to disease listed in the literature.

Genomic prediction of leaf rust resistance to Arabica coffee using machine learning algorithms

Genomic selection (GS) emphasizes the simultaneous prediction of the genetic effects of thousands of scattered markers over the genome. Several statistical methodologies have been used in GS for the prediction of genetic merit. In general, such methodologies require certain assumptions about the data, such as the normality of the distribution of phenotypic values. To circumvent the non-normality of phenotypic values, the literature suggests the use of Bayesian Generalized Linear Regression (GBLASSO). Another alternative is the models based on machine learning, represented by methodologies such as Artificial Neural Networks (ANN), Decision Trees (DT) and related possible refinements such as Bagging, Random Forest and Boosting. This study aimed to use DT and its refinements for predicting resistance to orange rust in Arabica coffee. Additionally, DT and its refinements were used to identify the importance of markers related to the characteristic of interest. The results were compared with those from GBLASSO and ANN. Data on coffee rust resistance of 245 Arabica coffee plants genotyped for 137 markers were used. The DT refinements presented equal or inferior values of Apparent Error Rate compared to those obtained by DT, GBLASSO, and ANN. Moreover, DT refinements were able to identify important markers for the characteristic of interest. Out of 14 of the most important markers analyzed in each methodology, 9.3 markers on average were in regions of quantitative trait loci (QTLs) related to resistance to disease listed in the literature.(AU)

Microdochium albescens may affect the physiological quality of irrigated rice cultivar seeds / Microdochium albescens pode afetar a qualidade fisiológica de sementes de cultivares de arroz irrigado

Knowledge of the effect of the seedborne inoculum is important for knowing the level of tolerance of the pathogen by the seed. This research evaluated the effect of the incidence of the fungus Microdochium albescens on the physiological quality of the seeds of different cultivars of irrigated rice. The study was carried out in the seed testing laboratory (STL), phytopathology laboratory and in greenhouse, located at the Center of Agroveterinary Sciences of the Santa Catarina State University, Lages, SC, Brazil. Seeds from six irrigated rice cultivars produced in the Alto Vale do Itajaí Region in the 2016/17 harvest, were used. The lots were submitted to the seed health test, identifying four lots per cultivar with a natural incidence of M. albescens, with two lots of each cultivar with an incidence greater than 40% and two lots equal or less than 40%, totaling 24 seed lots. The following evaluations were carried out on the lots: germination, accelerated aging test, emergence in a greenhouse at 14 days, emergence speed index (ESI), emergence speed (ES), shoot length, root length and fresh and dry mass. There was a significant interaction between cultivar and level of incidence only in the variables germination, vigor and root length. Fresh mass, shoot length and ESI were not affected, regardless of cultivar and incidence of fungus in the seed. The irrigated rice cultivars SCS118 Marquês and SCSBRS Tio Taka are susceptible to a high incidence (> 40%) of the fungus M. allbescens.(AU)

O conhecimento do efeito do inóculo na semente é importante para conhecimento do nível de tolerância do patógeno pela semente. Objetivo deste trabalho foi avaliar o efeito da incidência do fungo Microdochium allbescens sobre a qualidade fisiológica das sementes de diferentes cultivares de arroz irrigado. O estudo foi realizado nos laboratórios de análises de sementes (LAS), fitopatologia e na casa de vegetação, localizados no Centro de Ciências Agroveterinárias da Universidade do Estado de Santa Catarina, Lages, SC. Utilizaram-se sementes de seis cultivares de arroz irrigado produzidas na Região do Alto Vale do Itajaí na safra 2016/17. Os lotes foram submetidos ao teste de sanidade de sementes, identificando-se quatro lotes por cultivar com incidência natural de M. albescens, sendo designados dois lotes de cada cultivar com incidência superior a 40% e dois lotes igual ou inferior a 40%, totalizando 24 lotes de sementes. Foram realizadas as seguintes avaliações nos lotes: germinação, teste de envelhecimento acelerado, emergência em casa de vegetação aos 14 dias, índice de velocidade de emergência (IVE), velocidade de emergência (VE), comprimento de parte aérea, comprimento de raiz e massa seca. Houve interação significativa entre cultivar e nível de incidência apenas nas variáveis germinação, vigor e comprimento de raiz. A massa fresca, comprimento da parte aérea e IVE não foram afetados, independente do cultivar e incidência do fungo na semente. Os cultivares de arroz irrigado SCS118 Marquês e SCSBRS Tio Taka são suscetíveis à alta incidência (> 40%) do fungo M. albescens.(AU)

Morphophysiological characterization of Ceratocystis fimbriata isolates from yerba mate / Caracterização morfofisiológica de isolados de Ceratocystis fimbriata de erva-mate

This study aimed to morphologically characterize the isolates of Ceratocystis fimbriata from yerba mate and to evaluate the effect of culture medium and temperature on mycelial growth and sporulation of C. fimbriata. For the morphological characterization of the 11 monosporic isolates of the fungus, slides were prepared to determine the dimensions of the sexual and asexual structures of the fungus. Four experiments were conducted to evaluate the mycelial growth and to evaluate the sporulation of C. fimbriata in different culture mediums and temperatures. The isolates of C. fimbriata from yerba mate showed perithecia with brown to black necks, divergent ostiolar hyphae, hatshaped hyaline ascospores, single-celled, cylindrical endoconidia, and globular to ovoid aleurioconidia. PDA and V8-agar media showed the highest mycelial growth. The average optimum temperature for mycelial growth and sporulation of isolates of C. fimbriata of yerba mate were 22.5 and 22.4 ºC, respectively.(AU)

Este estudo teve como objetivo caracterizar morfologicamente os isolados de Ceratocystis fimbriata e avaliar o efeito do meio de cultura e da temperatura no crescimento micelial e na esporulação de C. fimbriata. Para a caracterização morfológica dos 11 isolados monospóricos do fungo foram preparadas lâminas para determinar as dimensões das estruturas sexuadas e assexuadas do fungo. Quatro experimentos foram conduzidos para avaliar o crescimento micelial e esporulação of C. fimbriata em diferentes meios de culturae temperaturas. Os isolados de C. fimbriata de erva-mate apresentaram peritécios com pescoço de marrom a preto, hifa ostiolar divergente, ascósporos hialinos em formato de chapéu, endoconídios unicelulares, cilíndricos, e aleuroconídios com formato globoso a ovoide. Os meios de cultura PDA e V8-ágar apresentaram os maiores crescimentos miceliais. A temperatura ótima média para crescimento micelial e esporulação dos isolados de C. fimbriata de erva-mate foram de 22,5 e 22,4 ºC, respectivamente.(AU)

Exposure of Toxocara canis eggs to Purpureocillium lilacinum as a biocontrol strategy: an experimental model evaluation / Exposição de ovos de Toxocara canis a Purpureocillium lilacinum como estratégia de biocontrole: uma avaliação em modelo experimental

Purpureocillium lilacinum is a nematophagous fungus used in biological control against some parasites, including Toxocara canis. This study researched the infectivity of embryonated T. canis eggs after exposure to the fungus P. lilacinum. T. canis eggs were exposed to P. lilacinum for 15 or 30 days and subsequently administered to Swiss mice (n=20). Control group consisted of mice who received T. canis embryonated eggs without fungal exposure. Forty-eight hours after infection, heart, lung, and liver from animals of each group were collected to assess larval recovery. The organs of mice that received embryonated eggs exposed to the fungus showed a lower average larval recovery (P 0.05) suggesting that exposure of T. canis eggs to P. lilacinum was able to reduce experimental infection. Under the evaluated conditions, the interaction time between the fungus and the parasite eggs was not a significant factor in larvae recovery. P. lilacinum may be considered a promising T. canis biological control agent. However, further studies are needed to determine a protocol for the use of this fungus as a biological control agent.(AU)

Purpureocillium lilacinum é um fungo nematófago com potencial para uso no controle biológico de parasitos, incluindo Toxocara canis. Este estudo pesquisou a infectividade de ovos de T. canis embrionados após exposição ao fungo P. lilacinum . Ovos de T. canis foram expostos ao fungo por 15 ou 30 dias e subsequentemente administrados a camundongos Swiss (n=20). O grupo controle consistiu de camundongos que receberam ovos embrionados do parasita sem exposição ao fungo. Quarenta e oito horas após a infecção, coração, pulmão e fígado dos camundongos foram coletados para avaliar a recuperação larval. Os órgãos dos animais que receberam ovos embrionados expostos ao fungo apresentaram menor média de recuperação larval (P 0,05) do que os infectados com ovos sem exposição ao fungo, sugerindo que a exposição dos ovos de T. canis a P. lilacinum foi capaz de reduzir a infecção experimental. Nas condições avaliadas, o tempo de interação entre o fungo e os ovos do parasito não foi um fator significativo na recuperação das larvas. P. lilacinum pode ser considerado um promissor agente de controle biológico de T. canis, no entanto, mais estudos são necessários para avaliar o emprego deste fungo como um agente de controle biológico.(AU)

Avaliação de diferentes métodos de preservação do fungo Phoma Dimorpha / Evaluation of different methods of preservation of Phoma dimorpha fungus

Frente a necessidade de preservação e a manutenção de materiais biológicos, dentre eles fungos com potencial para controle biológico, para o desenvolvimento biotecnológico e científico, que vêm ganhando destaque no cenário mundial. Sendo necessário a adequação de métodos de preservação que além de garantia a sobrevivência destes microrganismos permitam a conservação de suas características morfológicas, fisiológicas e genéticas, no entanto, não existe um método ideal ou universal para a conservação de materiais biológicos. Diante desta necessidade o presente trabalho teve como objetivo de avaliar a eficácia e viabilidade de três métodos de preservação de isolados do fungo Phomadimorpha (repicagens periódicas, Castellani e fragmentos de papel-filtro), em dois períodos de avaliação, seis e doze meses após o armazenamento. Estudou-se a eficácia e viabilidade, através do crescimento micelial do fungo em meio de cultivo contendo batata-dextrose-ágar. Houve variabilidade entre os métodos de preservação do isolado do fungo P. dimorpha para o crescimento micelial, eficácia do método e índice de velocidade do crescimento micelial, nos dois períodos de avaliação, após seis e doze meses de armazenamento. O método de preservação em fragmento de papel filtro mostrou-se como o mais eficaz na preservação do isolado do fungo P. dimorpha nos dois períodos de avaliação, após seis e doze meses de armazenamento, sendo ideal para obter o maior o crescimento micelial, eficácia do método e índice de velocidade do crescimento micelial.

Facing the need for preservation and maintenance of biological materials, among them fungi with potential for biological control, for biotechnological and scientific development, which are gaining prominence in the world scenario. It is necessary to adapt preservation methods that besides guaranteeing the survival of these microorganisms allow the conservation of their morphological, physiological and genetic characteristics, however, there is no ideal or universal method for the conservation of biological materials. In view of this need, the present work had the objective of evaluating the efficacy and feasibility of three methods for the preservation of Phoma dimorpha (periodic transfer, Castellani and filter paper fragments) isolates in two evaluation periods, six and twelve months after the storage. Efficacy and viability were studied by mycelial growth of the fungus in a culture medium containing potato-dextrose-agar. There was variability between the preservation methods of the P. dimorpha fungus isolate for mycelial growth, method efficacy and mycelial growth rate index, in the two evaluation periods, after six and twelve months of storage. The filter paper fragment preservation method was the most effective in reserving the P. dimorpha fungus isolate in the two evaluation periods, after six and twelve months of storage, being ideal to obtain the highest mycelial growth, efficacy of the method and mycelial growth rate index.

Avaliação de diferentes métodos de preservação do fungo Phoma Dimorpha / Evaluation of different methods of preservation of Phoma dimorpha fungus

Frente a necessidade de preservação e a manutenção de materiais biológicos, dentre eles fungos com potencial para controle biológico, para o desenvolvimento biotecnológico e científico, que vêm ganhando destaque no cenário mundial. Sendo necessário a adequação de métodos de preservação que além de garantia a sobrevivência destes microrganismos permitam a conservação de suas características morfológicas, fisiológicas e genéticas, no entanto, não existe um método ideal ou universal para a conservação de materiais biológicos. Diante desta necessidade o presente trabalho teve como objetivo de avaliar a eficácia e viabilidade de três métodos de preservação de isolados do fungo Phomadimorpha (repicagens periódicas, Castellani e fragmentos de papel-filtro), em dois períodos de avaliação, seis e doze meses após o armazenamento. Estudou-se a eficácia e viabilidade, através do crescimento micelial do fungo em meio de cultivo contendo batata-dextrose-ágar. Houve variabilidade entre os métodos de preservação do isolado do fungo P. dimorpha para o crescimento micelial, eficácia do método e índice de velocidade do crescimento micelial, nos dois períodos de avaliação, após seis e doze meses de armazenamento. O método de preservação em fragmento de papel filtro mostrou-se como o mais eficaz na preservação do isolado do fungo P. dimorpha nos dois períodos de avaliação, após seis e doze meses de armazenamento, sendo ideal para obter o maior o crescimento micelial, eficácia do método e índice de velocidade do crescimento micelial.(AU)

Facing the need for preservation and maintenance of biological materials, among them fungi with potential for biological control, for biotechnological and scientific development, which are gaining prominence in the world scenario. It is necessary to adapt preservation methods that besides guaranteeing the survival of these microorganisms allow the conservation of their morphological, physiological and genetic characteristics, however, there is no ideal or universal method for the conservation of biological materials. In view of this need, the present work had the objective of evaluating the efficacy and feasibility of three methods for the preservation of Phoma dimorpha (periodic transfer, Castellani and filter paper fragments) isolates in two evaluation periods, six and twelve months after the storage. Efficacy and viability were studied by mycelial growth of the fungus in a culture medium containing potato-dextrose-agar. There was variability between the preservation methods of the P. dimorpha fungus isolate for mycelial growth, method efficacy and mycelial growth rate index, in the two evaluation periods, after six and twelve months of storage. The filter paper fragment preservation method was the most effective in reserving the P. dimorpha fungus isolate in the two evaluation periods, after six and twelve months of storage, being ideal to obtain the highest mycelial growth, efficacy of the method and mycelial growth rate index.(AU)

Water potential and time of Pyrenophora tritici-repentis inoculation in wheat seeds / Potencial hídrico e duração da inoculação com Pyrenophora tritici-repentis em sementes de trigo

Wheat seeds infected with Pyrenophora tritici-repentis, the causal agent of tan spot, are partially responsible for outbreaks caused by this pathogen. Seed lots with a high incidence of P. tritici-repentis must be rapidly acquired for transmission and pathogen-control studies. Therefore, the aim of this study was to determine whether changes in water potential of culture medium and variations in inoculation time might favor the infection of wheat seeds by P. tritici-repentis without compromising seed viability. Colonies of P. tritici-repentis were grown on potato-dextrose-agar (PDA) culture medium, adjusted to a water potential of -0.36 MPa, under water stress induced by mannitol at potentials of -0.4, -0.6, -0.8, -1.0, and -1.2 MPa. Analyses were carried out to determine mycelial growth index and seed exposure time to the culture medium to start germination as a function of water potential. Afterwards, wheat seeds were placed in contact with colonies of P. tritici-repentis for 24, 48, and 72 hours at potentials of -0.4, -0.6, -0.8, -1.0, and -1.2 MPa. The experiment was arranged in a completely randomized design, in a factorial scheme (water potential × inoculation time). Rates of germination, seedling emergence in soil, and seed infection were assessed. Mycelial growth was stimulated at lower water potentials, which germinated faster. A 24-hour inoculation time and a -0.4 MPa water potential were efficient toinfect wheat seeds with P. tritici-repentis, without hindering seedling germination and emergence underlaboratory conditions.(AU)

Sementes de trigo infectadas com Pyrenophora tritici-repentis, agente causal da mancha-amarela da folha, respondem em parte pelas epidemias causadas por este patógeno. A obtenção rápida de lotes de sementes com alta incidência de P. tritici-repentis é fundamental para estudos de transmissão e controle. Sendo assim, o objetivo deste trabalho foi verificar se alterações no potencial hídrico do meio de cultura e variações na duração da inoculação podem favorecer a infecção de sementes de trigo por P. tritici-repentis, sem comprometer a viabilidade destas sementes. Colônias do patógeno foram cultivadas sobre meio de cultura batata-dextrose-ágar (BDA) básico, no potencial hídrico de -0,36 MPa, e no meio BDA com restrição hídrica, causada pela adição de manitol, nos potenciais hídricos de -0,4, -0,6, -0,8, -1,0 e -1,2 MPa. Foram realizadas análises para determinar o índice de crescimento micelial do fungo e o tempo de exposição das sementes ao meio de cultura para o início do processo germinativo em função dos potenciais hídricos. Posteriormente, sementes de trigo foram colocadas em contato com as colônias de P. tritici-repentis durante 24, 48 e 72 horas nos potenciais hídricos de -0,4, -0,6, -0,8, -1,0 e -1,2 MPa, em esquema fatorial (potenciais hídricos x duração da inoculação) e delineamento inteiramente casualizado. Foram avaliadas as taxas de germinação, de emergência de plântulas em condições de laboratório.(AU)

Sensibilidade do laminocultivo Dermatobac® para o diagnóstico da endometrite fúngica em éguas / Sensibility of microcultivation assay Dermatobac® for fungal endometritis diagnosis in mares

Among different etiologic factors, fungal endometritis is a common cause of decreased mares fertility.Two experiments were conducted to evaluate the sensitivity of Dermatobac®, a microculture system originally developed for the isolation of fungi that concerns Human Medicine. In Experiment 1, standard(ATCC) strains of Candida (n=4) and Aspergyllus (n=1) were grown and visually analyzed daily for 7days. For Experiment 2, 34 mares were selected and subjected to material harvesting for completionof uterine cytology as well as seeding with Dermatobac®. After 24h of cultivation, the macroscopicobservation of all Candida and Aspergyllus strains (Experiment 1) was possible. In Experiment 2,five animals showed presence of yeast on cytologic slides (14.71%), results also confirmed sowingin Dermatobac® system (100% sensitivity). Five false positive cases were observed, characterizedby microbiological growth in Dermatobac® but not confirmed by endometrial cytology, determiningspecificity of 85%. However, the results did not compromise the efficiency of Dermatobac® systemgiven all contaminants presented differentiated morphology and higher growing time (P 0.05)when compared to the major etiological agents of equine fungal endometritis. The Dermatobac®system proved to be efficient for the macroscopic diagnosis of fungal endometritis in horses, showingconclusive information only after 24 hours of culture.

Dentre os diferentes fatores etiológicos, a endometrite fúngica representa uma causa frequente deinfertilidade na égua. Nesse sentido, dois experimentos foram realizados para avaliar a sensibilidadedo Dermatobac®, sistema originalmente desenvolvido para o isolamento de fungos de interesse emMedicina Humana. No Experimento 1, cepas padrão de Candida (n=4) e Aspergyllus (n=1) foramsemeadas assepticamente e em duplicata no sistema Dermatobac®, acompanhando-se o crescimentofúngico a cada 24 horas por 7 dias. Para o Experimento 2, foram selecionadas 34 éguas, submetidasà colheita de material uterino para o plaqueamento em Dermatobac® e realização de esfregaços parapesquisa direta de fungos (Controle). No Experimento 1, foi possível a observação macroscópica detodas as cepas de Candida e Aspergyllus a partir de 24 horas do início do cultivo microbiológico.No Experimento 2, foi constatada a presença de leveduras nas lâminas citológicas de cinco animais(14,71%), resultados também confirmados na semeadura em Dermatobac® (sensibilidade de 100%).Foram observados cinco casos falso-positivos caracterizados pelo crescimento microbiológico emsistema Dermatobac® não confirmados através da citologia endometrial, resultados que determinarama especificidade de 85%. No entanto, todos os casos falso-positivos foram atribuídos a microrganismos contaminantes que apresentaram morfologia diferenciada e tempo de crescimento superior (P<0,05)ao apresentado pelos principais agentes etiológicos das endometrites fúngicas equinas. Conclui-se que o sistema Dermatobac® é eficiente para o diagnóstico macroscópico da endometrite fúngica em equinos, gerando informações visuais a partir de 24 horas de cultivo.

Application of the BacT/ALERTR 3D system for sterility testing of injectable products

Sterility testing as described in the pharmacopoeia compendia requires a 14-day incubation period to obtain an analytical result. Alternative methods that could be applied to evaluating product sterility are especially interesting due to the possibility of reducing this incubation period and thus the associated costs. The aims of this study were to evaluate the performance of the BacT/ALERT^R 3D system in detecting microorganisms in large-volume parenteral solutions that were intentionally contaminated and to compare this system to pharmacopoeia sterility testing using the membrane filtration method. The results indicated that there were no significant differences between the methods regarding the ability to detect microbial contamination; however, detection with the BacT/ALERT^R 3D system was faster compared to the pharmacopoeia method. Therefore, the BacT/ALERT^R 3D system is a viable alternative for assessing the sterility of injectable products..(AU)

Sensibilidade do laminocultivo Dermatobac® para o diagnóstico da endometrite fúngica em éguas / Sensibility of microcultivation assay Dermatobac® for fungal endometritis diagnosis in mares

Among different etiologic factors, fungal endometritis is a common cause of decreased mares fertility.Two experiments were conducted to evaluate the sensitivity of Dermatobac®, a microculture system originally developed for the isolation of fungi that concerns Human Medicine. In Experiment 1, standard(ATCC) strains of Candida (n=4) and Aspergyllus (n=1) were grown and visually analyzed daily for 7days. For Experiment 2, 34 mares were selected and subjected to material harvesting for completionof uterine cytology as well as seeding with Dermatobac®. After 24h of cultivation, the macroscopicobservation of all Candida and Aspergyllus strains (Experiment 1) was possible. In Experiment 2,five animals showed presence of yeast on cytologic slides (14.71%), results also confirmed sowingin Dermatobac® system (100% sensitivity). Five false positive cases were observed, characterizedby microbiological growth in Dermatobac® but not confirmed by endometrial cytology, determiningspecificity of 85%. However, the results did not compromise the efficiency of Dermatobac® systemgiven all contaminants presented differentiated morphology and higher growing time (P 0.05)when compared to the major etiological agents of equine fungal endometritis. The Dermatobac®system proved to be efficient for the macroscopic diagnosis of fungal endometritis in horses, showingconclusive information only after 24 hours of culture.(AU)

Dentre os diferentes fatores etiológicos, a endometrite fúngica representa uma causa frequente deinfertilidade na égua. Nesse sentido, dois experimentos foram realizados para avaliar a sensibilidadedo Dermatobac®, sistema originalmente desenvolvido para o isolamento de fungos de interesse emMedicina Humana. No Experimento 1, cepas padrão de Candida (n=4) e Aspergyllus (n=1) foramsemeadas assepticamente e em duplicata no sistema Dermatobac®, acompanhando-se o crescimentofúngico a cada 24 horas por 7 dias. Para o Experimento 2, foram selecionadas 34 éguas, submetidasà colheita de material uterino para o plaqueamento em Dermatobac® e realização de esfregaços parapesquisa direta de fungos (Controle). No Experimento 1, foi possível a observação macroscópica detodas as cepas de Candida e Aspergyllus a partir de 24 horas do início do cultivo microbiológico.No Experimento 2, foi constatada a presença de leveduras nas lâminas citológicas de cinco animais(14,71%), resultados também confirmados na semeadura em Dermatobac® (sensibilidade de 100%).Foram observados cinco casos falso-positivos caracterizados pelo crescimento microbiológico emsistema Dermatobac® não confirmados através da citologia endometrial, resultados que determinarama especificidade de 85%. No entanto, todos os casos falso-positivos foram atribuídos a microrganismos contaminantes que apresentaram morfologia diferenciada e tempo de crescimento superior (P<0,05)ao apresentado pelos principais agentes etiológicos das endometrites fúngicas equinas. Conclui-se que o sistema Dermatobac® é eficiente para o diagnóstico macroscópico da endometrite fúngica em equinos, gerando informações visuais a partir de 24 horas de cultivo.(AU)

Effect of arbuscular mycorrhizal fungi on young vines in copper-contaminated soil

Abstract High copper (Cu) levels in uprooted old vineyard soils may cause toxicity in transplanted young vines, although such toxicity may be reduced by inoculating plants with arbuscular mycorrhizal fungi (AMF). The objective of this study was to evaluate the effects of AMF on the plant growth, chlorophyll contents, mycorrhizal colonization, and Cu and phosphorus (P) absorption in young vines cultivated in a vineyard soil contaminated by Cu. Commercial vineyard soil with high Cu levels was placed in plastic tubes and transplanted with young vines, which were inoculated with six AMF species (Dentiscutata heterogama, Gigaspora gigantea, Acaulospora morrowiae, A. colombiana, Rhizophagus clarus, R. irregularis) and a control treatment on randomized blocks with 12 replicates. After 130 days, the mycorrhizal colonization, root and shoot dry matter (DM), height increment, P and Cu absorption, and chlorophyll contents were evaluated. The height increment, shoot DM and chlorophyll contents were not promoted by AMF, although the root DM was increased by R. clarus and R. irregularis, which had the greatest mycorrhizal colonization and P uptake. AMF increased Cu absorption but decreased its transport to shoots. Thus, AMF species, particularly R. clarus and R. irregularis, contribute to the establishment of young vines exposed to high Cu levels.(AU)

Estratégias para produção de celulases através de fermentação submersa utilizando fungos isolados do bioma brasileiro / Strategies to increase cellulase production with submerged fermentation using fungi isolated from the Brazilian biome

fermentação submersa utilizando fungos isolados do bioma brasileiro RESUMO. Estudos sobre novas fontes microbianas e análises mais acuradas das etapas que compõem a produção de celulases são essenciais como estratégias para diminuir os custos gerados pelo uso de celulases nos processos de obtenção de açúcares fermentescíveis. O trabalho teve como objetivo a seleção de fungos filamentosos produtores de celulases e a investigação de parâmetros que envolvem a produção enzimática em fermentação submersa. O primeiro teste consistiu em selecionar os melhores fungos produtores de celulases totais em frascos Erlenmeyer contendo 200 mL de meio de cultura específico. O teste subsequente teve o intuito de investigar a produção enzimática com quatro tipos de açúcares solúveis: glicose, lactose, sacarose e xilose. Nos testes em biorreator foram analisados três diferentes estratégias de inoculação. Na etapa de seleção a melhor atividade de FPase foi apresentada por Trichoderma sp. CMIAT 041 (49,9 FPU L-1) e CMCase pelo fungo Lasiodiplodia theobromae CMIAT 096 (350,0 U L-1). O uso de sacarose mostrou-se ser a melhor opção dentre os açúcares solúveis testados, apresentando os maiores valores de atividade de FPase (49,9 FPU L-1) e CMCase (119,7 U L-1). A melhor estratégia de inoculação foi a suspensão de esporos obtidos a partir de fermentação em farelo de trigo, no tempo 72h.(AU)

Studies on new microbial sources of cellulase and accurate assessment of the steps that increase cellulase production are essential strategies to reduce costs of various processes using such enzymes. This study aimed at the selection of cellulase-producing filamentous fungi, and at the research of parameters involving cellulase production by submerged fermentation. The first test consisted of selecting the best cellulase-producing microorganisms (FPase) in Erlenmeyer flasks containing 200 mL of specific growth medium. The next test was designed to further investigate the enzyme production in fermentation with four types of soluble sugars: glucose, lactose, sucrose and xylose. In bioreactor tests, three different inoculation strategies were analyzed. The best FPase activity was presented by the strain Trichoderma sp. CMIAT 041 (49.9 FPU L-1) and CMCase by the fungus Lasiodiplodia theobromae CMIAT 096 (350.0 U L-1). Sucrose proved to be the best option among the soluble sugars tested, with higher rates of FPase activity (49.9 FPU L-1) and CMCase (119.7 U L-1). The best inoculation strategy for the bioreactor was a spore suspension obtained from a semi-solid state fermentation of wheat bran for 72h.(AU)

Nasal, oral and rectal microbiota of Black lion tamarins (Leontopithecus chrysopygus)

Black lion tamarins (Leontopithecus chrysopygus) are endangered callithrichids. Their conservation may require future translocations or reintroductions; however these approaches involve risks of pathogen introduction in the environment and stress-related opportunistic infections in these animals. In order to screen for opportunistic and potential pathogenic bacterial and fungal microbiota, ten free-ranging and ten captive Black lion tamarins were studied and the results compared. Nasal, oral and rectal swabs were collected and cultured for aerobic and facultative anaerobic bacteria and fungi, and a total 203 bacterial and 84 fungal isolates were obtained. Overall, the most frequent organisms were Staphylococcus spp., Bacillus spp., Candida spp. and Aspergillus spp. Microbiota of free-ranging and captive animals were similar in composition. A number of potentially pathogenic organisms were identified, emphasizing the importance of microbiological screening in future translocation or reintroduction conservation management programs.

Filamentous fungi and media for cellulase production in solid state cultures

Cellulase production was evaluated in two reference strains (T. reesei Rut-C30 and T. reesei QM9414), two strains isolated from a sugarcane cultivation area (Trichoderma sp. IPT778 and T. harzianum rifai IPT821) and one strain isolated in a program for biodiversity preservation in São Paulo state (Myceliophthora thermophila M77). Solid state cultures were performed using sugarcane bagasse (C), wheat bran (W) and/or soybean bran (S). The highest FPA was 10.6 U/gdm for M77 in SC (10:90) at 80% moisture, which was 4.4 times higher than production in pure W. C was a strong inducer of cellulase production, given that the production level of 6.1 U/gdm in WC (40:60) was 2.5 times higher than in pure W for strain M77; T. reesei Rut-C30 did not respond as strongly with about 1.6-fold surplus production. S advantageously replaced W, as the surplus production on SC (20:80) was 2.3 times relative to WC (20:80) for M77.(AU)

Impact of Amazon land use on the community of soil fungi

Considered as one of the most biodiverse biomes, the Amazon has a featured role in the discovery of new species of plants, animals and microorganisms, which may be important for the functionality of different ecosystems. However, studies on the impacts resulted from changes in the Amazon land use on microbial communities and their functions are still limited. In this context, the soil fungal diversity can act as an important indicator of environmental stress caused by land use of the Amazon. This study describes changes in soil fungal communities caused by different systems of land use (primary forest, secondary forest, agroforestry, agriculture and pasture). Communities were observed in each of the areas using denaturing gradient gel electrophoresis (DGGE) of 18S rRNA gene combined with the non-metric multidimensional scaling (NMDS). Unique bands indicated the dominance of particular fungal groups in each of the specific treatments, mainly in areas converted to pasture, which differed greatly from samples of other systems of land use (SLU). The analysis of partial sequence of the 18S rRNA gene of fungi in soils under primary forest, agriculture and pasture showed differences (p = 0.001), evidencing the fungal community response to such changes. Most abundant phyla were the Zygomycota in the soil under primary forest and agricultural land, and Basidiomycota in the soil under pasture. The results show that the Amazon soil is an ecosystem susceptible to environmental changes in regarding the fungi community inhabiting this niche.(AU)

Impact of Amazon land use on the community of soil fungi

Considered as one of the most biodiverse biomes, the Amazon has a featured role in the discovery of new species of plants, animals and microorganisms, which may be important for the functionality of different ecosystems. However, studies on the impacts resulted from changes in the Amazon land use on microbial communities and their functions are still limited. In this context, the soil fungal diversity can act as an important indicator of environmental stress caused by land use of the Amazon. This study describes changes in soil fungal communities caused by different systems of land use (primary forest, secondary forest, agroforestry, agriculture and pasture). Communities were observed in each of the areas using denaturing gradient gel electrophoresis (DGGE) of 18S rRNA gene combined with the non-metric multidimensional scaling (NMDS). Unique bands indicated the dominance of particular fungal groups in each of the specific treatments, mainly in areas converted to pasture, which differed greatly from samples of other systems of land use (SLU). The analysis of partial sequence of the 18S rRNA gene of fungi in soils under primary forest, agriculture and pasture showed differences (p = 0.001), evidencing the fungal community response to such changes. Most abundant phyla were the Zygomycota in the soil under primary forest and agricultural land, and Basidiomycota in the soil under pasture. The results show that the Amazon soil is an ecosystem susceptible to environmental changes in regarding the fungi community inhabiting this niche.

Detection of airborne psychrotrophic bacteria and fungi in food storage refrigerators

The purpose of this study was to determine the microbiological air quality (psychrotrophic bacteria and airborne fungi) and distribution of fungi in different types of ready-to-eat (RTE) food-storage refrigerators (n=48) at selected retail stores in the city of Edirne, Turkey. Refrigerators were categorized according to the type of RTE food-storage: meat products, vegetables, desserts, or a mix of food types. Microbiological quality of air samples was evaluated by using a Mas-100 Eco Air Sampler. Four refrigerators (all containing meat products, 8.3%) produced air samples with undetectable microorganisms. The highest detected mean value of airborne psychrotrophic bacteria and fungi was 82.3 CFU/m³ and 54.6 CFU/m³, respectively and were found in mixed-food refrigerators. The dominant airborne fungal genera found were Penicillium (29.0%), Aspergillus (12.0%), Mucor (9%), Cladosporium (8%), Botyrtis (7%), and Acremonium (6%). By definition, RTE food does not undergo a final treatment to ensure its safety prior to consumption. Therefore, ensuring a clean storage environment for these foods is important to prevent food-borne disease and other health risks.(AU)

Microbial diversity in Brazilian mangrove sediments: a mini review

The importance and protection of mangrove ecosystems has been recognized in Brazilian Federal law since 1965. Being protected in law, however, has not always guaranteed their protection in practice. Mangroves are found in coastal and estuarine locations, which are prime real estate for the growth of cities, ports and other economic activities important for Brazilian development. In this mini-review we introduce what mangroves are and why they are so important. We give a brief overview of the microbial diversity found in mangrove sediments and then focus on diversity studies from Brazilian mangroves. We highlight the breadth and depth of knowledge about mangrove microbial communities gained from studying Brazilian mangroves. We report on the exciting findings of molecular microbial ecology methods that have been very successfully applied to study bacterial communities. We note that there have been fewer studies that focus on fungal communities and that fungal diversity studies deserve more attention. The review ends with a look at how a combination of new molecular biology methods and isolation studies are being developed to monitor and conserve mangrove ecosystems and their associated microbial communities. These recent studies are having a global impact and we hope they will help to protect and re-establish mangrove ecosystems.(AU)