This paper investigates the recent climatic variability and changes in snow line and ice front position in Collins Glacier, King George Island, South Shetland Islands, Antarctic Peninsula. This region has recorded one of the largest temperature increases in the past fifty years and has been demonstrated to be highly sensitive to climate changes. To monitor recent changes (1983–2006), we determined the fluctuations of the terminus and snow line of the glacier via remote sensing data and field observation in the summer of 2013. We conclude that the Collins Glacier has responded slowly to regional climate changes (decades or even centuries), as glacial responses to climatic events do not depend solely on one environmental variable. The glacier presented more retreat and elevation of the snow line in the north sector. The retreat data are correlated with the mean monthly temperature and annual number of days of melting‐degree variations.

Technological processes mediated by microorganisms and enzymes are promising alternatives for treatment of recalcitrant residues. Keratinases hydrolyze keratin, the primary component of some wastes generated in many industrial activities. The present study was designed to evaluate strategies for obtaining keratinases produced by fungi using submerged fermentation and two residues as substrates, chicken feathers and swine hair. Two fungi isolated from feather residues showed potential for keratinase production, Fusarium oxysporum and Aspergillus sp. These were subjected to submerged fermentation using chicken feathers and swine hair prepared in three conditions (microbial concentration reduction, sterilization and hydrogen peroxide). The residual mass was quantified and tested for keratinase production. The most potent enzymatic extract was used in the precipitation technique with salts and organic solvents. The best results of enzymatic activity were obtained using F. oxysporum, on the 6thday of fermentation, obtaining 243.25 U mL −1 using sterilized swine hair as the substrate. Aspergillus sp. showed the highest keratinolytic activity on the 9thday, 113.50 U mL −1 using feathers as the substrate. The highest degradation percentage was 59.20% (w/w) in swine hair and the precipitation technique, with relative activities close to 50%. The results are promising for the application of residues and microorganisms in biotechnological processes of economic and environmental interest.

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A preocupação com a geração de resíduos provenientes da produção de alimentos tem se intensificado. Isto porque estes resíduos possuem altas concentrações de matéria orgânica, que causam danos se não forem tratados adequadamente. Uma forma de tratar de maneira eficaz estes resíduos é por meio da compostagem. O objetivo deste trabalho foi contribuir para a melhoria dos processos de compostagem de resíduos agroindustriais gerados em pequenas propriedades rurais. Para isso, realizou-se uma avaliação microbiológica em processos de compostagem em pequena escala em amostras de três sistemas distintos localizados na região sul do Brasil, para verificar a presença de microrganismos potencialmente patogênicos como E. coli, Salmonella spp., fungos filamentosos e leveduriformes. Foi verificado que nos sistemas com controles de aeração a presença de patogênicos foi menor apenas para E.coli, porém houve permanência de Salmonella spp. e fungos nos três sistemas avaliados apontando para a necessidade de melhoria nos sistemas de compostagem utilizados pelas pequenas propriedades rurais. A presença de Salmonella nos compostos dos três sistemas evidencia o risco à saúde pública e a necessidade de padronização e melhoria do processo de compostagem hoje utilizados.

Keratinous residues are generated in large quantities in industrial processes and because of this they are difficult to manage because the presence of keratin. Keratinases are emerging as promising alternatives in technological processes. The objective of this work was to determine the potential of pretreatment of agro-industrial residues using an ultrasonic probe, and to evaluate activity enhancement strategies by analyzing the behavior of enzymatic activity of keratinases exposed to various reaction systems as well as to enzymatic concentration. We tested the application of enzymatic extracts in the degradation of keratinous residues. Submerged fermentation was performed with swine hair pretreated with and without ultrasonic probe. The enzymatic extracts were exposed to reaction systems and the enzymatic concentration technique to measure the increments of enzymatic activity. We found that the ultrasonic probe increased reaction rates, enabling higher enzyme production in shorter time periods. The ultrasonic probe reached 38.4% of relative activity and the enzyme concentration, increased the enzymatic activity in 53.5%. We observed potential degradation of chicken feathers with homemade enzyme extracts. Taken together, our findings suggest that the results obtained in this work are promising, despite the fact that the data in this area are scarce.