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Aims@#Thermophilic proteases are important industrial enzymes because they can be used at high temperatures in various bioprocessing schemes. The bacterial population of the Cholistan desert was explored for thermophilic proteases and their industrial applications.@*Methodology and results@#Three bacterial isolates K1, K5 and K7 were found promising protease producers. These isolates were preliminary identified as Bacillus based on morphological characteristics and biochemical tests (positive for catalase, oxidase and citrate tests, and negative for indole and urease tests). The isolates K1, K5 and K7 were further identified as Priestia endophytica, Lysinibacillus cresolivorans and Bacillus subtilis, respectively by phylogenetic analysis. The isolates grew best at 50 °C and P. endophytica (K1), L. cresolivorans (K5) and B. subtilis (K7) produced larger zones of hydrolysis at 37 °C, 45 °C and 50 °C at pH 7, respectively. The optimum temperature where protease activity was maximum was 65 °C for P. endophytica and L. cresolivorans and 55 °C for B. subtilis, and the optimum pH was 9.@*Conclusion, significance and impact of study@#The proteases produced by these isolates were found active at high temperatures (45 °C to 85 °C) and high pH (9-12), which make them industrially important thermoalkaliphilic proteases. These proteases successfully de-haired cow’s skin and de-stained blood from cotton cloth pieces, which are rarely tested applications of these proteases.
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Deserto , Peptídeo HidrolasesRESUMO
Systems of soil cultivation and use directly influence crop yield by interfering with the soil chemical, physical, and biological attributes. This study aimed to evaluate the correlation between maize grain yield, soil chemical and biological attributes, and the occurrence of nematodes in maize crops grown in the off-season, in the state of Mato Grosso do Sul. Soil samples from 21 off-season maize crops were collected in 2015. The samples were used to identify and quantify nematodes, determine biomass carbon and microbial activity, and for chemical analysis. The attributes were clustered based on the variables evaluated using the mean Euclidean distance and Ward's clustering method. The interrelationship between the variables was analyzed by correlations, and its unfolding in the cause and effect investigations was evaluated by the path analysis. Organic matter and microbial biomass carbon positively influence grain yield. Magnesium negatively influences the population of Pratylenchulus spp. in maize crops. The potential acidity and organic matter are related to the presence of Rotylenchulus spp.
Sistemas de cultivo e uso do solo influenciam diretamente o rendimento das culturas, interferindo nos atributos químicos, físicos e biológicos do solo. Este trabalho teve como objetivo avaliar a correlação entre a produtividade de grãos de milho, os atributos químicos e biológicos do solo e a ocorrência de nematoides em milho cultivado no período de entressafra, no estado do Mato Grosso do Sul. Amostras de solo de 21 safras de milho fora de temporada foram coletadas em 2015. As amostras foram usadas para identificar e quantificar os nematóides, determinar a atividade microbiana e o carbono da biomassa, e para análises químicas. Os atributos foram agrupados com base nas variáveis avaliadas usando a distância euclidiana média e o método de agrupamento de Ward. A inter-relação entre as variáveis foi analisada por meio de correlações, e seu desdobramento nas investigações de causa e efeito foi avaliado pela análise de trilha. A matéria orgânica e o carbono da biomassa microbiana influenciam positivamente o rendimento de grãos. O magnésio influencia negativamente a população de Pratylenchulus spp. nas culturas de milho. A acidez potencial e a matéria orgânica estão relacionadas à presença de Rotylenchulus spp.
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Solo , Zea mays , NematoidesRESUMO
Abstract To accelerate the recovery of degraded environments, it is necessary to use ecological restoration techniques, which require validation according to the ecosystem conditions where are implemented. This work aimed to evaluate soil microbiological attributes under different ecological restoration technologies in a subtropical forest. The study was conducted at UTFPR-DV, southwest of Paraná, in an ecotone between Mixed Ombrophilous Forest and Semideciduous Seasonal Forest and on an Oxisol. In December 2010, a tillage area of at least 17 years old was isolated and the passive restoration, tree planting and nucleation treatments were installed in 40x54 m plots and four replications. In November 2018 the soil was sampled in these plots and in a native forest area as a reference. There were calculated soil organic carbon content (OCC) and microbiological attributes such as microbial biomass N and C (NMIC and CMIC), basal respiration, fungal spore content and the metabolic (qCO2) and microbial quotient (MICq). It can be concluded that nucleation technology can restore soil microbiological attributes but has not yet reached the conditions of a natural environment. Passive restoration is not a good technology for restoring soil microbiological attributes. The higher contents of CMIC, NMIC, OCC, MICq and fungal spores in the soil under native forest compared to ecological restoration technologies indicate that eight years of adoption of these techniques have not yet been enough to fully recover soil microbiological activity.
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Microbiologia do Solo , Florestas , Conservação dos Recursos Naturais/métodos , Esporos Fúngicos , Clima Tropical , Brasil , Carbazóis , Carbono/análise , Nitrogênio/análiseRESUMO
Objective To study the structure and differences of bacterial communities in different soils, and to explore the effectiveness of 16S rRNA sequencing in identification of different soil. Methods Soil samples from 7 places in Shanghai were collected, then bacterial genomic DNA were extracted from them. The fragments of hypervariable region from 16S rRNA sequences were sequenced with high-throughput sequencing techniques. The results were quantified or visualized with bioinformatics software. The differences in diversity and abundance among the three kinds of bacterial communities in soil samples from grassland, forests and beaches were compared and analyzed. Results The statistical differences that existed among the alpha diversity indexes of bacterial communities in soil samples of grassland, forests and beaches had statistical significance. The relative abundance and diversity of bacterial communities in these three kinds of soil were significantly different. Grassland soil had higher Acidobacteria abundance, forest soil had higher Proteobacteria abundance, beach soil had higher Actinobacteria abundance. However, the differences in soil bacterial communities in artificial grasslands, natural grasslands and industrial district grasslands did not have statistical significance. Conclusion 16S rRNA sequencing can effectively distinguish different soils. This method may be able to provide clues for first crime scene inference in criminal cases.
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Biodiversidade , China , DNA Bacteriano/genética , Genética Forense , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Filogenia , RNA Ribossômico 16S/genética , Microbiologia do SoloRESUMO
Abstract We used 16S rRNA sequencing to assess the archaeal communities across a gradient of Cerrado. The archaeal communities differed across the gradient. Crenarcheota was the most abundant phyla, with Nitrosphaerales and NRPJ as the predominant classes. Euryachaeota was also found across the Cerrado gradient, including the classes Metanocellales and Methanomassiliicoccaceae.
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Plantas/microbiologia , Microbiologia do Solo , Archaea/isolamento & purificação , Filogenia , Plantas/classificação , Solo/química , Brasil , Archaea/classificação , Archaea/crescimento & desenvolvimento , Archaea/genética , Biodiversidade , Desenvolvimento VegetalRESUMO
Abstract The sugarcane in Brazil is passing through a management transition that is leading to the abolition of pre-harvest burning. Without burning, large amounts of sugarcane trash is generated, and there is a discussion regarding the utilization of this biomass in the industry versus keeping it in the field to improve soil quality. To study the effects of the trash removal on soil quality, we established an experimental sugarcane plantation with different levels of trash over the soil (0%, 50% and 100% of the original trash deposition) and analyzed the structure of the bacterial and fungal community as the bioindicators of impacts. The soil DNA was extracted, and the microbial community was screened by denaturing gradient gel electrophoresis in two different seasons. Our results suggest that there are no effects from the different levels of trash on the soil chemistry and soil bacterial community. However, the fungal community was significantly impacted, and after twelve months, the community presented different structures among the treatments.
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Microbiologia do Solo , Bactérias/isolamento & purificação , Saccharum/microbiologia , Fungos/isolamento & purificação , Estações do Ano , Solo/química , Bactérias/classificação , Bactérias/genética , Brasil , Saccharum/crescimento & desenvolvimento , Biodiversidade , Fungos/classificação , Fungos/genéticaRESUMO
São poucas as informações na literatura sobre herbicidas para aplicação em pós-emergência da cultura da mandioca e seus possíveis impactos na atividade microbiana do solo. Dessa forma, objetivou-se com este trabalho avaliar o efeito da aplicação de herbicidas pós-emergentes em área total e dirigida na atividade microbiana de solo cultivado com mandioca, bem como seu efeito no controle das plantas daninhas e no crescimento inicial da cultura. O experimento foi conduzido em campo, no Distrito do Planalto, na cidade de Diamantina-MG. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições e os tratamentos foram constituídos de uma testemunha capinada, uma testemunha cultivada sem o controle de plantas daninhas e a aplicação dos herbicidas: fluazifop-p-butil, fomesafen, glyphosate, paraquat e a mistura de herbicidas fluazifop-p-butil + fomesafem. De maneira geral, os herbicidas estudados apresentaram controle satisfatório das plantas daninhas presentes na área de plantio e causaram baixa intoxicação visual à mandioca. A mistura dos herbicidas fomesafen e fluazifop-p-butil promoveram um controle mais prolongado das plantas infestantes, mas com influência negativa à microbiota do solo. Os herbicidas paraquat e glyphosate apresentaram potencial para aplicação dirigida nas entrelinhas da mandioca.
There is little information in the literature on herbicides for post-emergence application of cassava and its potential impacts on soil microbial activity. Thus, the aim of this work was to evaluate the effect of postemergence herbicides in total area and direct microbial activity in soil cultivated with cassava, as well as its effect on weed control and early growth of the crop. The experiment was conducted in the field, in the Planalto District, the city of Diamantina-MG. The experimental design was a randomized block with four replications and treatments were made up of one weed control, one control grown without weed control and herbicide application: fluazifop-p-butyl and fomesafen, glyphosate, paraquat and the mixture herbicide fluazifop-p-butyl + fomesafem. In general, the herbicides showed satisfactory control of weeds in the planting area and caused low toxicity to visual cassava. The mixture of herbicides fomesafen and fluazifop-p-butyl promoted a more prolonged control of weeds, but with negative influence on soil microbes. The herbicide paraquat and glyphosate showed potential for application directed between the lines of cassava.
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Microbiologia do Solo , Manihot , Plantas Daninhas , HerbicidasRESUMO
O sistema de manejo interfere nas propriedades microbiológicas do solo, que por sua vez afeta a ciclagem de nutrientes, alterando, portanto, a sua sustentabilidade. Dentre os vários indicadores microbiológicos do solo, estão a quantificação e qualificação de esporos de fungos micorrízicos e sua colonização radicular. O objetivo deste trabalho foi avaliar o efeito de forragens e/ou culturas em consórcio, na população micorrízica autóctone, através da análise quantitativa e qualitativa de esporos no solo e colonização radicular das culturas e/ou pastagens. As culturas e/ou forragens instaladas em cada piquete foram: 1. Panicum maximum cv Aruana; 2. Brachiaria humidicola + milho; 3. Brachiaria humidicola; 4. Panicum maximum cv Aruana + milho; 5. Soja (Glycine max); 6. Soja. A colonização micorrízica foi influenciada pela interação entre plantas; os dados mostraram que a presença do Panicum maximum cv. Aruana, em comparação com Brachiaria humidicola, alterou a colonização radicular do milho. Parece ocorrer associação preferencial de espécies de fungos a determinados hospedeiros. Os gêneros de maior ocorrência após a implantação das culturas e forragens foram: Glomus sp., Acaulospora sp. e Scutelospora cerradensis.
Soil management alters their microbiological properties and consequently the nutrient cycling which also affects sustentability. Among several microbiological soil indicators, can be outstanding micorhizal fungus spores quantification and qualification and root colonization. The aim of this research was evaluate the effect of several planting culture in crop and livestock integration on autoctone populations of mycorrhyzal fungus, through quantitative and qualitative analysis of soil spores and root colonization of crops and pastures. Crops and/or pastures were planted in each plot were: 1. Panicum maximum cv Aruana; 2. Brachiaria humidicola + maize (Zea mays); 3. Brachiaria humidicola; 4. Panicum maximum cv Aruana + maize; 5. Soybean (Glycine max); 6. Soybean. It was observed that root colonization was influenced by the interaction between plants and the date showed that Panicum maximum cv. Aruana compared with Brachiaria humidicola affected root colonization in maize. The results indicated a preferencial association between fungi species to certain host plants. After planting crops and pastures, the genera with higher occurrence were: Glomus sp., Acaulospora sp. e Scutelospora cerradensis.
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Microbiologia do Solo , Análise do Solo , Alimentos , Brachiaria , Fungos , PanicumRESUMO
OBJECTIVES: To determine 1) the degree of soil contamination by parasites; 2) the prevalence of contaminated samples; 3) the overall number of parasitic forms, by distance between the collection site and the domicile; 4) the mean number of parasite forms per peri-household area; and 5) the variables associated with the total number of parasite forms. METHODS: Soil samples were collected in the peridomicile of 18 (out of a total sample of 63) and 22 (out of 190) residences of the Faxinal and Ivaí indigenous territories (ITs), respectively, from March 2005 through October 2006, and evaluated by the methods of Baermann, modified Faust et al., and Lutz. RESULTS: The overall prevalence of samples contaminated by enteroparasites of humans or of animals with zoonotic potential was 75.7 percent (84 out of 111) in Faxinal and 96.2 percent (127 out of 132) in Ivaí. The most prevalent parasites were Ascaris spp., Isospora spp., and Toxocara spp. Positive statistical associations were observed between the number of parasitic forms per domicile and the following variables: time of year (season), the presence of bathrooms in the domicile, and the presence of excrement on peridomiciliar soil. CONCLUSIONS: The high level of soil contamination in Faxinal and Ivaí 1) constitutes a potential source of parasitic infection and 2) suggests that the treatment of human and animal excreta continues to be inadequate.
OBJETIVOS: Determinar: 1) el grado de contaminación parasitaria del suelo; 2) la prevalencia de muestras contaminadas; 3) el número general de formas parasitarias, en función de la distancia entre el sitio donde se tomaron las muestras y el domicilio; 4) el número promedio de formas parasitarias por área peridomiciliar y 5) las variables relacionadas con el número total de formas parasitarias. MÉTODOS: Se recogieron muestras del suelo de los alrededores de 18 (de una muestra total de 63) y 22 domicilios (de una muestra total de 190) situados en los territorios indígenas Faxinal e Ivaí, respectivamente, entre marzo del 2005 y octubre del 2006. Las muestras se evaluaron mediante los métodos propuestos por Baermann, Faust et al. (modificado) y Lutz. RESULTADOS: La prevalencia general de las muestras contaminadas por enteroparásitos humanos o animales que se consideraron de potencial zoonótico fue de 75,7 por ciento (84 de 111) en Faxinal y de 96,2 por ciento (127 de 132) en Ivaí. Las especies de parásitos más prevalentes fueron Ascaris, Isospora y Toxocara. Se observó una asociación estadística positiva entre el número de formas parasitarias halladas en los alrededores de cada domicilio y las siguientes variables: la época del año (estación), la existencia de baños domiciliarios y el hallazgo de excremento en el suelo peridomiciliar. CONCLUSIONES: La gran contaminación del suelo hallada en Faxinal e Ivaí constituye una posible fuente de infección parasitaria e indica que sigue siendo insuficiente el tratamiento de los excrementos de seres humanos y animales.
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Humanos , Animais , Parasitos/isolamento & purificação , Microbiologia do Solo , Animais Domésticos/parasitologia , Brasil/epidemiologia , Fezes/parasitologia , Helmintíase/epidemiologia , Helmintíase/prevenção & controle , Helmintíase/transmissão , Habitação , Higiene , Indígenas Sul-Americanos , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/prevenção & controle , Enteropatias Parasitárias/transmissão , Enteropatias Parasitárias/veterinária , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias em Animais/prevenção & controle , Doenças Parasitárias em Animais/transmissão , Prevalência , Infecções por Protozoários/epidemiologia , Infecções por Protozoários/prevenção & controle , Infecções por Protozoários/transmissão , Engenharia SanitáriaRESUMO
Objective To study the ecological characteristics of toxigenic fungi in soil of the suburban villages of Zhangzhou, Fujian. Methods 48 soil samples were collected from 24 natural villages in Zhangzhou and cultured in bengal rose agar plate, then the fungal count and species identification were carried out. Results The numbers of fungi in unit area in 48 soil samples were in the normal rang. 3357 strains of 34 fungal genera were found in sampled soil samples. Fusarium and Penicillium were the dominant genera, as well as Trichoderma, Parcilomyces, Cladosporium which were commonly detectable. 4 strains of Aspergillus flavas were found, 2 of them were toxigenic. Aflatoxin B 1 production were 6?7 ng/g respectively and they didnt produce AFB 2? AFG 1? AFG 2. 2 strains of A. versicolor both produced sterigmatocystin. Conclusion Aspergillus flavus showed lower proportion in mycoflora and weaker capability for producing aflatoxins in soil of suburban villages of Zhangzhou. This data obtained could be used as the basis for agriculture areal programme.