Production and characterization of a biosurfactant produced by Streptomyces sp. DPUA 1559 isolated from lichens of the Amazon region

Surfactants are amphipathic compounds containing both hydrophilic and hydrophobic groups, capable to lower the surface or interfacial tension. Considering the advantages of the use of biosurfactants produced by microorganisms, the aim of this paper was to develop and characterize a biosurfactant produced by Streptomyces sp. DPUA1559 isolated from lichens of the Amazon region. The microorganism was cultured in a mineral medium containing 1% residual frying soybean oil as the carbon source. The kinetics of biosurfactant production was accompanied by reducing the surface tension of the culture medium from 60 to values around 27.14 mN/m, and by the emulsification index, which showed the efficiency of the biosurfactant as an emulsifier of hydrophobic compounds. The yield of the isolated biosurfactant was 1.74 g/L, in addition to the excellent capability of reducing the surface tension (25.34 mN/m), as observed from the central composite rotational design when the biosurfactant was produced at pH 8.5 at 28°C. The critical micelle concentration of the biosurfactant was determined as 0.01 g/mL. The biosurfactant showed thermal and pH stability regarding the surface tension reduction, and tolerance under high salt concentrations. The isolated biosurfactant showed no toxicity to the micro-crustacean Artemia salina, and to the seeds of lettuce (Lactuca sativa L.) and cabbage (Brassica oleracea L.). The biochemistry characterization of the biosurfactant showed a single protein band, an acid character and a molecular weight around 14.3 kDa, suggesting its glycoproteic nature. The results are promising for the industrial application of this new biosurfactant.

Spirometry reference values in the Brazilian population

The aim of the present study was to provide new spirometry reference equations in a sample of the Brazilian population for the following parameters: forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FVC ratio, peak of expiratory flow (PEF), forced expiratory flow at 50% (FEF50%), 75% average vital capacity (FEF25-75%), and average forced expiratory flow time (FEFT). This was a prospective study using results from chest radiographs, electrocardiograms, and questionnaires to investigate the participants' respiratory symptoms, sedentarism, and comorbidities (Charlson comorbidity index). From December 2010 to July 2014, individuals were randomly selected from various locations in the state of Rio de Janeiro. All individuals were examined by a single technician in the morning at the laboratory, and performed the spirometry with the same spirometer. Spirometry values were tabulated for the creation of three equation models: linear regression, logarithmic regression, and logarithms through a method that incorporates the lambda, median, and coefficient of variation (LMS method). Initially, 7003 individuals from both genders were contacted, and 454 were recruited. The data from the new equations were compared with one Brazilian and eight international equations, resulting in a high correlation (r>0.9). The values derived from the LMS method and linear regression were very similar (P>0.5), and both could be used to acquire the reference values for Brazilian spirometry. Data derived from the equations of this study were different from the current Brazilian equation, which could be justified by the different method used.

Public green areas and urban environmental quality of the city of São Carlos, São Paulo, Brazil / Áreas verdes públicas e a qualidade ambiental urbana do Município de São Carlos, Estado de São Paulo, Brasil

Abstract Assess the state of public green areas, their importance and influence on environmental quality and living in urban centers is an arduous task considering the conceptual and scientific regarding quantification and data analysis methods divergence. In this study, we aimed to determine two indicators of public green areas relative to the percentage of public green areas (PPGA) and the public green areas index (PGAI) in the urban area of São Carlos, SP. The study area was organized into administrative regions (ARs), using satellite images, topographical maps of 1:10,000 Geographic and Cartographic Institute (1990) and data provided by the Municipality of São Carlos. The results show that public green areas comprise 6.55% of the municipality, with a public green areas index (PGAI) of 18.85 m2/inhabitant, indicating good urban environmental quality when compared to rates of 15 m2/capita for public green areas for recreation, suggested by the Brazilian Society of Urban Forestry. The differences between the administrative regions are concern with situations from 4.16 to 36.30 m2/inhabitant. In this context, it is recommend specific public policies and popular participation in the process of continuous improvement for increasing public green areas in the less favored regions. The Genebrino method applied to indicators of public green areas (GPGA – amount of public green areas divided by population density), showed a commendable goal above 40% for urban environmental quality.

Resumo Diagnosticar a situação das áreas verdes públicas, sua importância e influência na qualidade ambiental e de vida nos centros urbanos é uma tarefa árdua, considerando a divergência conceitual e de métodos científicos no que tange a quantificação e a análise dos dados. Neste estudo, objetivou-se determinar dois indicadores de áreas verdes públicas, referentes ao percentual de áreas verdes públicas (PAVP) e ao índice de áreas verdes públicas (IAVP) no perímetro urbano do Município de São Carlos, SP. A área de estudo foi organizada em regiões administrativas (RAs), utilizando imagens de satélite, cartas topográficas 1:10.000 do Instituto Geográfico e Cartográfico (1990) e dados fornecidos pela Prefeitura Municipal de São Carlos. Os resultados demonstram que as áreas verdes públicas compreendem 6,55% do território do município, com um índice de áreas verdes públicas (IAVP) de 18,85 m2/habitante, indicando uma boa qualidade ambiental urbana quando comparado aos índices de 15 m2/habitante para áreas verdes públicas destinadas à recreação, sugerido pela Sociedade Brasileira de Arborização Urbana. As diferenças entre as regiões administrativas são preocupantes, com situações de 4,16 a 36,30 m2/habitantes. Neste contexto, recomendam-se políticas públicas específicas e a participação popular no processo de melhoria contínua para o incremento das áreas verdes públicas nas regiões menos favorecidas. O método genebrino, aplicado aos indicadores de áreas verdes públicas (IAVP – somatório das áreas verdes públicas dividido pela densidade populacional), apontou uma meta recomendável acima de 40% para a qualidade ambiental urbana.