Diversity and distribution of hidden cultivable fungi associated with marine animals of Antarctica.

In the present study, we surveyed the distribution and diversity of fungal assemblages associated with 10 species of marine animals from Antarctica. The collections yielded 83 taxa from 27 distinct genera, which were identified using molecular biology methods. The most abundant taxa were Cladosporium sp. 1, Debaryomyces hansenii, Glaciozyma martinii, Metschnikowia australis, Pseudogymnoascus destructans, Thelebolus cf. globosus, Pseudogymnoascus pannorum, Tolypocladium tundrense, Metschnikowia australis, and different Penicillium species. The diversity, richness, and dominance of fungal assemblages ranged among the host; however, in general, the fungal community, which was composed of endemic and cold-adapted cosmopolitan taxa distributed across the different sites of Antarctic Peninsula, displayed high diversity, richness, and dominance indices. Our results contribute to knowledge about fungal diversity in the marine environment across the Antarctic Peninsula and their phylogenetic relationships with species that occur in other cold, temperate, and tropical regions of the World. Additionally, despite their extreme habitats, marine Antarctic animals shelter cryptic and complex fungal assemblages represented by endemic and cosmopolitan cold-adapted taxa, which may represent interesting models to study different symbiotic associations between fungi and their animal hosts in the extreme conditions of Antarctica.

Tratamento térmico de lodo anaeróbio com utilização do biogás gerado em reatores UASB: avaliação da autossustentabilidade do sistema e do efeito sobre a higienização e a desidratação do lodo / Thermal treatment of anaerobic sludge utilizing biogas produced in UASB reactors: evaluation of system self-sustainability and the effect on sludge hygienization and dehydration

O presente trabalho objetiva avaliar a eficiência do biogás gerado em reatores UASB como fonte de energia para higienização térmica do lodo excedente, atentando-se ainda para a autossustentabilidade do sistema e para a avaliação do desaguamento do lodo tratado termicamente. Foi desenvolvido em um aparato experimental em escala de demonstração constituído de reator UASB, reservatório de biogás, reator térmico e leitos de secagem. A autossustentabilidade foi verificada por meio de balanço térmico teórico e de testes experimentais de higienização térmica. Estes testes indicaram que o aproveitamento da energia térmica do biogás foi suficiente para aquecer o lodo em temperaturas de 55 a 65ºC, durante três a cinco horas, possibilitando a completa eliminação de ovos viáveis de helmintos. No entanto, o processo de desidratação se mostrou muito mais difícil para o lodo tratado termicamente.

The objective of this research was to determine how effectively biogas produced in UASB reactors could be used as a source of heat for the thermal hygienization of excess anaerobic sludge, whether the system can operate on a self-sustained basis and how the dehydration of the thermally treated sludge behave. The experiments were conducted in a demonstration-scale setup comprising UASB reactor, biogas holder, thermal reactor and sludge drying beds. The self-sustainability of the system was evaluated by the systemâ€TMs theoretical thermal balance and by experimental hygienization tests. These tests indicated that the recovery of thermal energy from the biogas was sufficient to heat the sludge at temperatures in the range of 55 to 65ºC, for three to five hours, allowing the complete elimination of viable helminth eggs. However, the dehydration process showed to be much more difficult for the thermally treated sludge.