Transmission line silicon rubber insulators are frequently subjected to harsh environmental conditions that can change their surface characteristics and result in a transient or permanent loss of hydrophobicity. Algae, fungi, mould, and lichen are examples of biological growth that can compromise the power system's ability to operate safely by lowering the insulator's flashover voltage. We evaluated and identified the major microorganisms that could be responsible for the flashovers of insulators in South Africa. Due to the difficulty of accessing insulators currently in use within the electricity network, only two insulators, from two provinces in South Africa, were used in the study. Although algae were not found on the insulators, two major filamentous fungi identified as Curvularia sp. and Aspergillus sp. were isolated. The absence of algae could be attributed to the weather pattern of the two locations where the insulators were placed during their use as part of the network. According to previous studies worldwide, the high occurrence of these fungi could be linked to the reduction of flashover voltage of the composite insulators. Although a larger survey including more insulators from all provinces in South Africa should be conducted, the current study demonstrates the need for a cleaning programme for insulators using cost-effective eco-friendly antimicrobial agents. SIGNIFICANCE: • Degradation and loss of hydrophobicity on the overhead line composite due to biological growth were found to be an impediment to the safe operation of high-voltage insulators. Fungi were found to be the main factor causing the degradation of overhead transmission lines. • With these data, a model can be developed to predict the rate of biological growth on a given insulator, to estimate the degradation of the surface conditions with time for the utility to know when to remove them from the line. Such a model could lead to a more reliable and efficient power system and reduce the engineer's workload.

Resumo Este trabalho teve como objetivo avaliar o efeito da aplicação de plasma atmosférico na inativação de fungos na superfície de sementes de Erythrina velutina e em colônias fúngicas isoladas. Dois experimentos foram realizados em delineamento inteiramente casualizado: no primeiro, o plasma foi aplicado na superfície das sementes usando gás hélio e plasma atmosférico por três, seis e nove minutos, além do controle (sementes sem tratamento), constituindo sete tratamentos com cinco repetições cada; no segundo experimento, placas de Petri contendo o inóculo de diferentes fungos foram tratadas com plasma atmosférico por três, seis e nove minutos (Air-3, Air-6 e Air-9) e comparadas com fungos não tratados em placas de Petri sem tratamento (controle), totalizando quatro tratamentos e cinco repetições cada. Descobrimos que a aplicação de plasma atmosférico nas sementes de E. velutina por nove minutos teve efeito antimicrobiano sobre os fungos Aspergillus niger, Aspergillus flavus, Fusarium sp., Brachysporium sp. e Rhizopus sp. A formação de colônias fúngicas isoladas de sementes de E. velutina também foi inibida por três minutos de exposição à aplicação de plasma atmosférico, exceto para A. niger, cuja inibição ocorreu a partir de 6 minutos de exposição à aplicação de plasma atmosférico.

Abstract This study aimed to evaluate the effect of atmospheric plasma application on the inactivation of fungi on the surface of Erythrina velutina seeds and on isolated fungal colonies. Two experiments were conducted using a completely randomized design. First, plasma was applied to the surface of the seeds using helium gas and atmospheric plasma for 3, 6, and 9 min in addition to the control (untreated seeds), constituting seven treatments with five repetitions each. In the second experiment, Petri dishes containing the inoculum of different fungi were treated with atmospheric air plasma for 3, 6, and 9 min (Air-3, Air-6, and Air-9) and were compared with untreated fungi in Petri dishes without treatment (control), totaling four treatments and five repetitions each. We found that the application of atmospheric air plasma to E. velutina seeds for 9 min had an antimicrobial effect on the fungi Aspergillus niger, Aspergillus flavus, Fusarium sp., Brachysporium sp., and Rhizopus sp. The formation of fungal colonies isolated from E. velutina seeds was also inhibited by 3 min of exposure to atmospheric air plasma, except for A. niger, whose inhibition occurred after 6 min of exposure to atmospheric plasma.

Resumo A natureza é presenteada com uma grande variedade de plantas ornamentais que embelezam e limpam a natureza. Por causa de seu grande valor estético, existe a necessidade de proteger essas plantas de uma variedade de estresses bióticos e abióticos. Hibiscus rosa-sinensis (L.) é uma planta ornamental comumente conhecida como rosa-da-China ou graxa-de-estudante. É afetada por vários patógenos fúngicos e bacterianos. O presente estudo buscou isolar o patógeno da mancha foliar de H. rosa-sinensis e seu controle usando nanopartículas de prata (AgNPs). Com base nas características moleculares e morfológicas, o patógeno isolado da mancha foliar foi identificado como Aspergillus niger. As AgNPs foram sintetizadas no extrato de folhas de Calotropis procera e caracterizadas. A análise de espectroscopia UV-vis mostrou discretas bandas de ressonância plasmônica na superfície das AgNPs sintetizadas, mostrando a presença de aminoácidos aromáticos. A espectroscopia no infravermelho com transformada de Fourier (FTIR) descreveu a presença de grupos funcionais C-O, NH, C-H e O-H, que atuam como moléculas estabilizadoras e redutoras. A difração de raios X (DRX) revelou o tamanho médio (~32,43 nm) das AgNPs e a microscopia eletrônica de varredura (MEV) mostrou sua natureza esférica. Neste estudo, foi investigada a atividade antifúngica in vitro e in vivo de AgNPs. A análise da atividade antifúngica in vitro revelou a maior inibição do crescimento de micélio (87%) na concentração de 1,0 mg/ml de AgNPs. A mesma concentração de AgNPs inibiu a propagação da doença em folhas infectadas de H. rosa-sinensis. Esses resultados demonstraram significativa capacidade de controle de doenças das AgNPs e sugeriram seu uso em diferentes plantas ornamentais.

Abstract Nature is gifted with a wide range of ornamental plants, which beautify and clean the nature. Due to its great aesthetic value, there is a need to protect these plants from a variety of biotic and abiotic stresses. Hibiscus rosa-sinensis (L.) is an ornamental plant and it is commonly known as China rose or shoeblack plant. It is affected by several fungal and bacterial pathogens. Current study was designed to isolate leaf spot pathogen of H. rosa-sinensis and its control using silver nanoparticles (AgNPs). Based on molecular and morphological features, the isolated leaf spot pathogen was identified as Aspergillus niger. AgNPs were synthesized in the leaf extract of Calotropis procera and characterized. UV-vis spectral analysis displayed discrete plasmon resonance bands on the surface of synthesized AgNPs, depicting the presence of aromatic amino acids. Fourier transform infrared spectroscopy (FTIR) described the presence of C-O, NH, C-H, and O-H functional groups, which act as stabilizing and reducing molecules. X-ray diffraction (XRD) revealed the average size (~32.43 nm) of AgNPs and scanning electron microscopy (SEM) depicted their spherical nature. In this study, in vitro and in vivo antifungal activity of AgNPs was investigated. In vitro antifungal activity analysis revealed the highest growth inhibition of mycelia (87%) at 1.0 mg/ml concentration of AgNPs. The same concentration of AgNPs tremendously inhibited the spread of disease on infected leaves of H. rosa-sinensis. These results demonstrated significant disease control ability of AgNPs and suggested their use on different ornamental plants.

Resumo O gás ozônio é considerado um agente antimicrobiano seguro em indústrias alimentícias. Aqui, avaliamos as atividades antifúngicas e antiaflatoxigênicas do ozônio contra a contaminação fúngica em nozes. Os gêneros fúngicos mais predominantes em nozes foram Aspergillus, Penicillium, Fusarium e Rhizopus. O ozônio (4 ppm) reduziu significativamente a esporulação fúngica de A. flavus e sua produção de aflatoxinas. Curiosamente, o tratamento de nozes com ozônio reduziu a contagem total de fungos e aumentou a degradação de aflatoxinas em aproximadamente 95% e 85%, respectivamente. O ozônio apresentou alta eficiência para aumentar a permeabilidade da membrana celular e a lesão da parede celular dos fungos. O aumento do tempo de exposição do ozônio em nozes em até 180 minutos levou à redução do total de lipídios, carboidratos e proteínas em 41,2%, 42,7% e 38,4%, respectivamente, em pistache, amêndoa e amendoim. Em conclusão, a ozonização é uma abordagem de descontaminação adequada para reduzir a carga microbiana em nozes, quando usada com tempo de exposição adequado.

Abstract Ozone gas is considered as a safe antimicrobial agent in food industries. Here, we evaluated the antifungal and antiaflatoxigenic activities of ozone against fungal contamination in nuts. The most predominant fungal genera in nuts were Aspergillus, Penicillium, Fusarium, and Rhizopus. Ozone (4 ppm) significantly reduced the fungal sporulation of A. flavus and their aflatoxin production. Interestingly, ozone treatment of nuts reduced the total fungal count and increased aflatoxins degradation by approximately 95% and 85%, respectively. Ozone displayed high efficiency to increase the permeability of cell membrane and injury of cell wall of fungi. Increasing the exposure time of ozone in nuts up to 180 minutes showed to reduce the total lipid, carbohydrates, and protein by around 41.2%, 42.7% and 38.4% respectively, in pistachio, almond and peanuts. In conclusion, ozonation is a suitable decontaminating approach for reducing the microbial load in nuts, when used with suitable exposure time.

Resumo A administração de doenças de plantas é difícil devido à natureza dos fitopatógenos. O controle biológico é um método seguro para evitar problemas relacionados a doenças fúngicas que afetam a produtividade das culturas e algumas bactérias patogênicas ao homem. Para isso, a atividade antimicrobiana da alga marinha Sargassum muticum metanol e de extratos aquosos foi investigada contra patógenos bacterianos humanos e fitopatógenos fúngicos. Usando metanol a 70%, o pó de algas marinhas foi extraído do ensaio de aditivos alimentares, a ultraestrutura (TEM). Os resultados revelaram inibição significativa do extrato metanólico de S. muticum contra Salmonella typhi (25,66 mm), Escherichia coli (24,33 mm), Staphylococcus aureus (22,33 mm) e Bacillus subtilis (19,66 mm). Alguns fitopatógenos fúngicos inibiram significativamente Fusarium moniliforme (30,33 mm), Pythium ultimum (26,33 mm), Aspergillus flavus (24,36 mm) e Macrophomina phaseolina (22,66 mm). A investigação fitoquímica do extrato de S. muticum mostrou a presença de compostos fenólicos e flavonoides. Os resultados sugeriram que há um nível apreciável de potencial antioxidante na atividade de eliminação de DPPH de S. muticum (79,86%). Estudos ultraestruturais da hifa de Fusarium moniliforme cultivada em meio contendo extrato de S. muticum na concentração de 300 mg/ml mostraram espessamento da parede celular, desintegração do citoplasma, grandes corpos lipídicos e vacúolos. Em conclusão, nosso estudo revelou a atividade antibacteriana do extrato de S. muticum significativamente contra algumas bactérias Gram-positivas, Gram-negativas e atividade antifúngica contra alguns fungos fitopatogênicos e alguns produtores de micotoxinas. Flavonoides e fenólicos desempenham papel importante como antioxidantes e propriedades antimicrobianas. Tal estudo revelou que o extrato metanólico de S. muticum pode ser usado como biocontrole ecologicamente correto para fungos fitopatogênicos e aditivos alimentares para proteger os produtos pecuários.

Abstract Plant disease administration is difficult due to the nature of phytopathogens. Biological control is a safe method to avoid the problems related to fungal diseases affecting crop productivity and some human pathogenic bacteria. For that, the antimicrobial activity of the seaweed Sargassum muticum methanol and water extracts were investigated against human bacterial pathogens and fungal plant pathogens. By using 70 percent methanol, the seaweed powder was extracted, feeding additives assay, ultrastructure (TEM). Results revealed significant inhibition of S. muticum methanol extract against Salmonella typhi (25.66 mm), Escherichia coli (24.33 mm), Staphylococcus aureus (22.33 mm) and Bacillus subtilis. (19.66 mm), some fungal phytopathogens significantly inhibited Fusarium moniliforme (30.33mm), Pythium ultimum (26.33 mm), Aspergillus flavus (24.36mm), and Macrophomina phaseolina (22.66mm). Phytochemical investigation of S. muticum extract showed the presence of phenolic and flavonoid compounds. Results suggested that there is an appreciable level of antioxidant potential in S. muticum (79.86%) DPPH scavenging activity. Ultrastructural studies of Fusarium moniliforme hypha grown on a medium containing S. muticum extract at concentration 300mg/ml showed a thickening cell wall, disintegration of cytoplasm, large lipid bodies and vacuoles. In conclusion, our study revealed The antibacterial activity of S. muticum extract significantly against some Gram positive, Gram negative bacteria and antifungal activity against some phytopathogenic and some mycotoxin producer fungi. Flavonoids, phenolic play an important role as antioxidants and antimicrobial properties. Such study revealed that S. muticum methanol extract could be used as ecofriendly biocontrol for phytopathogenic fungi and feeding additives to protect livestock products.

Abstract The total cost of processes that use lipases can be reduced by using the mycelium or not purified crude extract with lipolytic activity. These catalysts can be used without complex purification and can show desirable properties to emerging applications like hydrolysis and biotransformation of vegetable oils. To explore the potential of multiple forms of lipases (produced by the same filamentous fungus species), this work investigated intracellular and extracellular lipases produced by Trichoderma koningii (intracellular lipases were never studied), Penicillium spp. F02 (isolated from industrial grease trap) and Aspergillus niger. For this, batch fermentations were conducted for 96h using olive oil as a carbon source. The submerged culture was interrupted with vacuum filtration to isolate the mycelium and crude extract. The lipolytic activities were determined by the hydrolysis method of olive oil. The best results were obtained for intracellular activity with T. koningii (81.5 U/g of dry biomass) and for extracellular activity with A. niger (10.6 U/mL of crude extract). Both were attained in 96h of fermentation. T. koningii showed an accumulation of intracellular lipases and a depreciated extracellular activity in the initial 24 hours, which can be reasonable indications that there is strong retention of lipases in the mycelium. Statistical analysis within the range of 37°C to 44°C associated with pH from 7.8 to 8.0 favored the activity of lipases from T. koningii. All these findings are promising for future studies in the enzymatic synthesis of biodiesel with lipases (intracellular and extracellular) from T. koningii.

ABSTRACT: This study determined the extraction conditions, chemical composition, and antimicrobial activities of the essential oils of Citrus nobilis. The results illustrated that soaking in the 9% (w/v) NaCl solution for 2 h with a sample and solvent ratio of 1:3 (w/v) and a subsequent extraction time of 45 min yielded the highest extraction efficiency, reaching 3.66% (w/w). The main chemical components of the essential oils were limonene (90.42%), β-myrcene (4.7%), and α-pinene (1.22%). The minimum inhibitory concentration (MIC) at the density of 5x104, 5x105, and 5x106 cells/mL of Escherichia coli were 100, 125, and 125 mg/mL, respectively; for Staphylococcus aureus were 75, 100, and 125 mg/mL, respectively; and for Bacillus cereus were 50, 75, and 100 mg/mL, respectively. The minimum bactericidal concentration (MBC) at densities of 5x104, 5x105, 5x106 cells/mL of E. coli were 175, 225, 225 mg/mL, S. aureus were 150, 200, 225 mg/mL, and B. cereus were 125, 175, 200 mg/mL, respectively. The inhibitory activities of Aspergillus flavus of orange essential oils according to the agar dilution method at concentrations of 0.025-0.1%) on the 5th day were 8.84-30.61%.

RESUMO: Este estudo teve como objetivo determinar as condições de extração, composição química e atividades antimicrobianas dos óleos essenciais de Citrus nobilis. Os resultados demonstram que a imersão na solução de NaCl a 9% (p/v) por 2 h com uma proporção de amostra e solvente de 1:3 (p/v) e um tempo de extração subsequente de 45 min produziu a maior eficiência de extração, atingindo 3,66 % (p/p). Os principais componentes químicos dos óleos essenciais foram limoneno (90,42%), β-mirceno (4,7%) e α-pineno (1,22%). A concentração inibitória mínima (CIM) na densidade de 5x104, 5x105 e 5x106 células/mL de Escherichia coli foram 100, 125 e 125 mg/mL, respectivamente, e para Staphylococcus aureus foram 75, 100 e 125 mg/mL, respectivamente, e para Bacillus cereus foram 50, 75 e 100 mg/mL, respectivamente. A concentração bactericida mínima (MBC) em densidades de 5x104, 5x105, 5x106 células/mL de E. coli foram 175, 225, 225 mg/mL, S. aureus foram 150, 200, 225 mg/mL e B. cereus foram 125, 175, 200 mg/mL, respectivamente. As atividades inibitórias de Aspergillus flavus dos óleos essenciais de laranja, de acordo com o método de diluição em ágar nas concentrações 0,025-0,1%, no dia cinco foram 8,84-30,61%.

ABSTRACT: Feathers are by-products that are generated in significant quantities by the poultry industry. Microbial bioconversion has been investigated as a promising strategy for the processing of feathers, since, along with the degradation of these keratinous materials, bioprocessing can result in value-added products. Thus, from the perspective of industrial microbiology, chicken feathers can be considered a raw material for obtaining microbial proteases. Within this context, this research investigated and characterized the production of extracellular proteases by Aspergillus sp., isolated from soil of the Amazon Rainforest. The enzymatic production was evaluated using several growth substrates (whole feathers, feather meal, human hair, casein, gelatin, peptone and chicken beaks). With highest enzyme production was obtained the feather meal (FM) and peptone. After 48 h of fermentation, FM degradation was 15.82%. The crude protease showed optimal activity at pH 5.0 and 37 °C and enzymatic activity was enhanced with the addition of 1 and 5 mM of CaCl2, MnSO4, KCl, MgSO4 and CuSO4. The detergents Tween 20 and Triton x-100, at concentrations 0.5 and 1% (v/v), tended to stimulate activity. The presence of 0.5 and 1% (v/v) of organic solvents (methanol, acetone, butanol, acetonitrile, isopropanol and DMSO), maintained the enzymatic activity. β-mercaptoethanolstimulated proteolytic activity in the enzymatic assays. This study suggested new direction for waste management with industrial applications giving rise to green technology for sustainable development.

RESUMO: As penas são subprodutos que são gerados em quantidades significativas pela indústria avícola. A bioconversão microbiana tem sido investigada como uma estratégia promissora para o processamento de penas, uma vez que, juntamente com a degradação desses materiais queratinosos, o bioprocessamento pode resultar em produtos de valor agregado. Assim, do ponto de vista da microbiologia industrial, as penas de frango podem ser consideradas matéria-prima para a obtenção de proteases microbianas. Dentro deste contexto, o objetivo deste trabalho foi investigar e caracterizar a produção de proteases extracelulares por Aspergillus sp., isolados de solo da floresta Amazônica. A produção enzimática foi avaliada utilizando diversos substratos de crescimento (penas inteiras, farinha de penas, cabelo humano, caseína, gelatina, peptona e bicos de frango). Com maior produção de enzima foi obtida a farinha de penas (FP) e peptona. Após 48 h de fermentação, a degradação da FP foi de 15.82%. A protease bruta mostrou atividade ótima em pH 5.0 e 37 0C e a atividade enzimática foi aumentada com a adição de 1 e 5 mM de CaCl2, MnSO4, KCl, MgSO4 e CuSO4. Os detergentes Tween 20 e Triton x-100, nas concentrações 0.5 e 1% (v/v), tenderam a estimular a atividade. A presença de 0.5 e 1% (v/v) dos solventes orgânicos (metanol, acetona, butanol, acetonitrila, isopropanol e DMSO), mantiveram a atividade enzimática. O β-mercaptoetanol estimulou a atividade proteolítica nos ensaios enzimáticos. Este estudo sugere uma nova direção para a gestão de resíduos com aplicações industriais dando origem à tecnologia verde para o desenvolvimento sustentável.

Resumo A avaliação do atraso de colheita de sementes de soja pode auxiliar na seleção de cultivares mais resistentes à deterioração no campo. O objetivo deste trabalho foi avaliar a qualidade fisiológica e sanitária de sementes de três cultivares de soja, submetidas ao atraso da colheita. Sementes das cultivares ‘NS 5959’, ‘BMX Potência’ e ‘TMG 1175’ foram colhidas em quatro épocas (R8; R8 + 10 dias; R8 + 20 dias e R8 + 30 dias) e avaliadas quanto ao grau de umidade, germinação, emergência, crescimento de plântulas e incidência de fungos. Houve redução na germinação e vigor das sementes das diferentes cultivares de soja, principalmente quando colhidas em R8 + 20 e R8 + 30 dias, devido à deterioração em campo. Além disso, o atraso na colheita proporcionou maior incidência de fungos nas sementes, principalmente Phomopsis sp., Aspergillus sp. e Cercospora kikuchii. Em geral, a cultivar ‘TMG 1175’ foi mais resistente à deterioração das sementes em campo causada pelo atraso de colheita.

Abstract The assessment of delayed harvesting of soybean seeds may help in the selection of cultivars more resistant to deterioration in the field. This work aimed to evaluate the physiological and sanitary quality of seeds of three soybean cultivars submitted to harvest delay. Seeds of the cultivars ‘NS 5959’, ‘BMX Potência’, and ‘TMG 1175’ were harvested in four periods (R8; R8 + 10 days; R8 + 20 days, and R8 + 30 days) and evaluated for the moisture content, germination, emergence, seedling growth, and fungal incidence. There was a reduction in germination and vigor of the seeds of the different soybean cultivars, especially when harvested at R8 + 20 and R8 + 30 days, due to deterioration in the field. In addition, the delay in harvest provided a higher incidence of fungi in the seeds, mainly Phomopsis sp., Aspergillus sp., and Cercospora kikuchii. In general, the cultivar ‘TMG 1175’ was more resistant to seed deterioration in the field caused by delayed harvesting.

Abstract Commercial dry food (CDF) for dogs is a whole grain ration thoroughly mixed and die-cut with heat and pressure to give it the shape of kibble. CDF is formulated with several agro-industrial ingredients and by-products of agricultural and livestock origin. Contamination by Aspergillus flavus and aflatoxins (AFs) in foods has been shown to be a global problem that causes harm to human and animal health. The objective was to evaluate the presence of fungal microbiota and contamination by AFs in CDF. A random sample (n= 77) of marketed CDF was selected in Aguascalientes, Mexico. The samples were processed and cultured by serial dilutions, obtaining monosporic isolates, which were characterized morphologically, toxigenically (HPLC), and molecularly (PCR). The concentration of AFs in CDF was quantified by HPLC. Fungal growth was observed in 53.2 % of CDF, and 7.8 % exceeded the maximum permissible limit (MPL=106 CFU/g). The genera Aspergillus, Penicillium, Cladosporium, Mucor, Alternaria, and Fusarium were found (69.4, 12.9, 9.4, 4.7, 1.7, and 1.1 %, respectively). All CDF samples showed contamination by AFs (14.8 ± 0.3 μg/kg), and 11.8 % exceeded the MPL (20.0 μg/kg) suggested by the regulations; contamination was significantly associated (P<0.05) with some ingredients used, CDF moisture, and inclusion of fungicides and sequestrants. The results obtained suggest that the CDF manufacturing process does not wholly eliminate contamination by fungi or by the AFs present in the ingredients used for its formulation; consequently, these remain in the finished product, putting at risk the health of dogs and the efficacy of the food chain.

Resumen El alimento comercial seco (ACS) para perro es una ración integral completamente mezclada y troquelada con calor y presión para darle forma de croqueta. El ACS está formulado con diversos ingredientes y subproductos agroindustriales de origen agrícola y pecuario. La contaminación por Aspergillus flavus y por aflatoxinas (AFs) en los alimentos se ha demostrado que es un problema global que causa daños a la salud humana y animal. El objetivo fue evaluar la presencia de microbiota fúngica y contaminación por AFs en el ACS. Una muestra aleatoria (n=77) de ACS comercializado se seleccionó en Aguascalientes, México. Las muestras fueron procesadas y cultivadas por diluciones seriadas, obteniendo aislados monospóricos, los cuales se caracterizaron morfológica, toxigénica (HPLC) y molecularmente (PCR). La concentración de AFs en ACS se cuantificó por HPLC. En el 53.2 % de ACS se observó crecimiento fúngico y 7.8 % superaron el límite máximo permisible (LMP=106 UFC/g). Se encontraron los géneros Aspergillus, Penicillium, Cladosporium, Mucor, Alternaria y Fusarium (69.4, 12.9, 9.4, 4.7, 1.7 y 1.1%, respectivamente). Todas las muestras de ACS mostraron contaminación por AFs (14.8 ± 0.3 µg/kg) y el 11.8 % excedió el LMP (20.0 µg/kg) sugerido por la normatividad; la contaminación se asoció significativamente (P<0.05) con algunos ingredientes empleados, humedad del ACS e inclusión de fungicidas y secuestrantes. Los resultados obtenidos sugieren que el proceso de elaboración del ACS no elimina completamente la contaminación por hongos ni por las AFs presentes en los ingredientes empleados para su formulación; en consecuencia, éstos permanecen en el producto terminado poniendo en riesgo la salud de los perros y eficacia de la cadena alimenticia.

RESUMEN La quitina es un polisacárido lineal producido por especies animales y fúngicas. Una de sus principales fuentes de obtención es el hongo Aspergillus niger, cultivado en biorreactores industriales. Es un biopolímero neutro que modifica las propiedades eléctricas de los materiales compuestos, una característica muy útil para algunos dispositivos electrónicos. Nuestro objetivo en este trabajo fue la caracterización fisicoquímica de películas de quitina, extraída de dicho hongo por un método químico asistido por ondas de choque y calor, así como también determinar su resistividad eléctrica al aplicarle altos voltajes (entre 10 y 20 kV). Las ondas de choque se utilizaron en este estudio porque se sabe que inducen poros en las células y podrían promover la entrada de álcali en la hifa, permitiendo una mejor eliminación de los componentes celulares residuales. La quitina fue neutralizada, secada y se formaron películas. Los valores de proteína residual se cuantificaron con la técnica de ácido bicinconínico (BCA), obteniendo películas con bajas cantidades de proteína. La caracterización del morfotipo específico extraído se estimó mediante infrarrojo transformado de Fourier (FTIR) y difracción de rayos X (XRD). Para evaluar la resistividad ante voltajes elevados, se diseñó un circuito especial que permitió detectar variaciones significativas de esta con respecto al voltaje aplicado, es decir, la quitina mostró un comportamiento coincidente con un varistor no lineal y, hasta donde sabemos, este es el primer informe de dicho comportamiento para la quitina.

ABSTRACT Chitin is a linear polysaccharide produced by animal and fungal species. One of its sources is the fungus Aspergillus niger, which is culturable in industrial bioreactors. Chitin is a neutral biopolymer that modifies the electrical properties of composite materials. These are useful features in some electronic devices. This study aimed to carry out physicochemical characterizations of chitin films obtained from the above-mentioned fungus, using a chemical method enhanced with exposure to heat and shock waves, and to determine their electrical resistivity at high voltages (between 10 and 20 kV). Shock waves were used in this study because they are known to induce pores into cells and could promote alkali entry into the hypha, allowing better removal of residual cellular components. Chitin was neutralized, dried, and films were produced. Residual protein values were quantified by bicinchoninic acid assay (BCA). The films obtained had low amounts of protein. The characterization of the specific morphotype extracted was done by FTIR and XRD. An especially designed circuit revealed significant variations of the resistivity as the voltage was varied. This behavior is typical of a non-linear varistor and, to the best of our knowledge, has not been reported for chitin.

RESUMEN Es poco común encontrar en la literatura casos de traqueobronquitis invasiva por aspergillus que se manifiesten como tumores endobronquiales que produzcan atelectasia pulmonar total. Aunque relatada en inmunocomprometidos, la morbimortalidad es considerable aun en pacientes sin enfermedad de base.

ABSTRACT It is rare to find in the literature cases of invasive aspergillus tracheobronchitis that manifest as endobronchial tumors that produce total pulmonary atelectasis. Although reported in immunocompromised patients, morbidity and mortality are considerable even in patients without underlying disease.

Abstract Airborne fungi are dispersed through the air. The aim of this study was to determine the prevalence of airborne fungi in Brazil and understand the relationship between fungal growth and respiratory diseases and infections. We conducted an integrative literature review of studies conducted in Brazil based on searches of the PubMed, MEDLINE-BIREME, SciELO, and LILACS databases for full-text articles published between 2000 and 2022. The searches returned 147 studies, of which only 25 met the inclusion criteria. The most prevalent genera of airborne fungi in Brazil are Aspergillus, Penicillium, Cladosporium, Curvularia, and Fusarium. The studies were conducted in the states of Maranhão, Ceará, Piauí, Sergipe, Mato Grosso, Pernambuco, Rio Grande do Sul, Santa Catarina, Rio de Janeiro, São Paulo, and Minas Gerais. The findings also show the relationship between fungi and meteorological factors and seasonality, the sensitivity of atopic individuals to fungi, and the main nosocomial mycoses reported in the literature. This work demonstrates the importance of maintaining good microbiological air quality to prevent potential airborne diseases.

Resumo Fungos anemófilos se dispersam na natureza através do ar atmosférico. O presente estudo objetivou caracterizar a prevalência da microbiota fúngica anemófila no Brasil e correlacionar o crescimento fúngico com doenças respiratórias e quadros infecciosos. Este trabalho é uma revisão integrativa de literatura construída a partir da busca nas bases de dados PubMed, BIREME, SciELO e LILACS, com inclusão de trabalhos brasileiros publicados entre 2000 e 2022, em língua portuguesa ou inglesa com texto online integral. O universo do estudo foi constituído por 147 publicações, das quais 25 compuseram a amostra por atenderem aos critérios de inclusão. Os gêneros de fungos aerotransportados mais prevalentes no Brasil são: Aspergillus sp., Penicillium sp., Cladosporium sp., Curvularia sp. e Fusarium sp. Os locais de origem dos estudos incluem Maranhão, Ceará, Piauí, Sergipe, Mato Grosso, Pernambuco, Rio Grande do Sul, Santa Catarina, Rio de Janeiro, São Paulo, Minas Gerais. Além disso, foi possível determinar a relação dos fungos com parâmetros meteorológicos e sazonalidade, a sensibilização de indivíduos atópicos aos fungos e as principais micoses nosocomiais relatadas na literatura. Assim, o trabalho destaca a importância da manutenção da qualidade microbiológica do ar com vistas a se prevenir possíveis doenças transmitidas pelo ar.

ABSTRACT The objective was to evaluate the inoculation with Aspergillus terreus and/or Trichoderma longibrachiatum on fermentation, chemical and microbiological composition of elephant grass ‘Cameroon’ silage (Cenchrus purpureus). Treatments were A. terreus at 105 colony forming units (CFU)/g (AT15), T. longibrachiatum at 105 CFU/g (TL20), a mixture of both at 105 CFU/g (MIX), and a control group without inoculation (CONTR). The design was completely randomized with seven replicates. The MIX silage was most stable, while CONTR, AT15, and TL20, had lower dry matter losses. There was no effect of inoculation in the chemical composition of silages. Only MIX silage (4.40) had pH above the minimum of 4.2 for humid grass silage and above the control (4.05). Bacteria from Diplococcus genus was identified at the opening of TL20 and CONTR silages. After air exposure, the population of rods, Lactobacillus, and total lactic acid bacteria was higher in theTL20 and MIX. The inclusion of a T. longibrachiatum and A. terreus mixture increases dry mater loss and silage pH. T. longibrachiatum was more efficient in maintaining populations of total lactic acid bacteria after opening; therefore, this strain has potential as an additive for elephant grass ‘Cameroon’ silage.

RESUMO O objetivo foi testar a inoculação com Aspergillus terreus e Trichoderma longibrachiatum sobre a fermentação, a composição bromatológica e microbiológica de silagem de capim-elefante cultivar ‘Cameroon’ (Cenchrus purpureus). Os tratamentos foram A. terreus a 105 unidades formadores de colônias (UFC)/g (AT15), T. longibrachiatum a 105 UFC/g (TL20), a mistura de ambos a 105 UFC/g (MIX), cada, e um controle não inoculado (CONTR). O delineamento foi inteiramente ao acaso, com sete repetições. A silagem MIX foi mais estável após abertura, enquanto CONTR, AT15 e TL20 apresentaram menor perda de massa seca. Não houve efeito de inoculação sobre a composição bromatológica das silagens. Apenas a silagem MIX (4,40) apresentou pH acima do mínimo de 4,2 para silagem de capim úmido e superior ao controle (4,05). Bactérias do gênero Diplococcus foram identificadas na abertura das silagens TL20 e CONTR. Após exposição ao ar, a população de bastonetes, Lactobacillus e bactérias láticas totais foram maiores em TL20 e MIX. A mistura de T. longibrachiatum e A. terreus aumenta a perda de matéria seca e o pH da silagem. T. longibrachiatum é mais eficiente em manter as populações de bactérias láticas totais após a abertura. Portanto, essa cepa tem potencial como aditivo para silagem de capim-elefante ‘Cameroon’.

Abstract: In the present contribution, the survey of entomopathogenic fungal diversity associated with organic yerba mate (Ilex paraguariensis A. St.-Hil.) crops allowed the identification of fungi with bioinsecticidal potential of great importance for pest management in organic crops. For this purpose, samples collected from 12 georeferenced sites of certified organic yerba mate plantations in the district of Bella Vista, Itapúa, were analyzed. Isolation and characterization of all fungal strains found in samples of live and dead insects was performed. The direct seeding plate methodology was applied and the colonies were analyzed macro and microscopically. As a result, and with favorable environmental conditions, it was possible to isolate the entomopathogenic fungus Beauveria as well as the genera Alternaria, Rhizopus, Absidia, Mucor, Aspergillus and Fusarium infecting dead insect tissues. In all sampling sites, Alternaria, Aspergillus and Fusarium genera were abundant and were preserved in straparia for future pathogenicity tests. The low frequency in which entomopathogenic fungi were found could be due to the intense droughts that occurred during the months of December/2021 to February/2022, drastically affecting the presence of insect pests and fungi sensitive to changes in temperature and humidity.

Resumen: En la presente contribución, el relevamiento de la diversidad fúngica entomopatógena asociada a cultivos orgánicos de yerba mate (Ilex paraguariensis A. St.-Hil.) permitió identificar los hongos con potencial bioinsecticida de gran importancia para el manejo de plagas en cultivos orgánicos. Para ello se analizaron muestras colectadas de 12 sitios georreferenciados de los yerbales orgánicos certificados del distrito de Bella Vista, Itapúa. Se realizó el aislamiento y caracterización de todas las cepas fúngicas encontradas en muestras de insectos vivos y muertos. Se aplicó la metodología de siembra directa en placa y se analizaron las colonias macro y microscópicamente. Como resultado, y con las condiciones ambientales favorables se pudo aislar el hongo entomopatógeno Beauveria como así también los géneros Alternaria, Rhizopus, Absidia, Mucor, Aspergillus y Fusarium infectando los tejidos de insectos muertos. En todos los sitios de muestreo abundaron los géneros Alternaria, Aspergillus y Fusarium que fueron conservados en cepario para futuros ensayos de patogenicidad. La baja frecuencia en que se encontraron los hongos entomopatógenos pudo deberse a las intensas sequías que acontecieron durante los meses de diciembre/2021 a febrero/2022, afectando drásticamente la presencia de insectos plagas y la de hongos sensibles a los cambios de temperatura y humedad.