Biovalorization of technical lignins for added-value products and applications

Lignin is an abundant non-toxic amorphous natural polymer. Nowadays it is available a great variety and large amounts of technical lignins as by-products from the pulp and paper industries. Some successful biotechnological applications of enzymatically modified lignins are described in the literature, namely for the production of lignin based copolymers, binders for wood composites, chelating agents, compositions for treating porous materials, coatings, paintings and others. From a new species from Bjerkandera genus which exhibits high decolourisation activity on Poly R-478 and Remazol Brilliant Blue R (RBBR) dyes, was isolated, purified and identified the main enzyme responsible for Remazol Brilliant Blue R dye decolourisation. Such an enzyme is able to oxidise manganese, as well as VA and DMP in manganese-independent reactions; the enzyme substrate range for oxidation of several phenolic and non-phenolic aromatic compounds was determined. This enzyme was tested for transformation of a lignin fraction obtained from straw pulping. Characterisation by gel filtration chromatography of the evolution of the molecular mass distribution of the lignin fragments generated by said enzyme indicated that this enzyme is able to interact directly with lignin in the absence of other mediators

Protocolo de avaliação agronômica de rochas e produtos derivados como fontes de nutrientes às plantas ou condicionadores de solo.

A dependência de importações de fertilizantes para garantir a reposição dos nutrientes retirados do solo com as colheitas dos produtos vegetais representa uma das principais fragilidades da agricultura brasileira. Assim, disponibilizar opções de diversificação de fontes de nutrientes, com base em matérias-primas locais, é uma meta para a pesquisa no País. São necessários esforços no sentido de viabilizar formas de exploração de ocorrências minerais pouco atrativas para a indústria tradicional de fertilizantes. Noutra vertente, em sintonia com os padrões de desenvolvimento reclamados pela sociedade moderna, a destinação de uma gama de resíduos de mineração, metalurgia e agroindústria pode ter a utilização agrícola como saída mais apropriada. Em todos os casos, essas potenciais novas fontes de nutrientes para a agricultura precisam ter sua eficiência agronômica e segurança de uso avaliadas segundo procedimentos e critérios embasados cientificamente. Nesta publicação propõe-se uma sequência metodológica a ser seguida em etapas de experimentação em ambiente controlado e em campo, de forma a se comprovar a possibilidade de uso agrícola de produtos derivados de rochas. O protocolo sugerido também pode servir de referência e ser adaptado ao estudo de outras fontes de nutrientes ou condicionadores de solo de naturezas diversasbitstream/item/70059/1/doc-143.pd

Pro-inflammatory triggers in childhood obesity: correlation between leptin, adiponectin and high-sensitivity C-reactive protein in a group of obese Portuguese children

INTRODUCTION: Pediatric obesity is increasingly prevalent in the Portuguese population. Adipocyte dysfunction results in the expression of pro-inflammatory mediators that are responsible for the low-grade inflammatory process that characterizes obesity. OBJECTIVES: The aim of this study was to investigate the relationship between markers of adiposity, inflammation and adipokines in a Portuguese obese pediatric population. METHODS: One hundred and twenty children of both sexes, aged 6-17 years, were included in this study. The control group consisted of 41 healthy normal-weight children. The variables analyzed were age, gender, body mass index, waist circumference, fat mass percentage, high-sensitivity C-reactive protein (hs-CRP), leptin and adiponectin. RESULTS: There were significant differences between controls and obese children for all parameters analyzed. In the obese group, after controlling for age and gender, hs-CRP (p=0.041), adiponectin (p=0.019) and leptin (p<0.001) still showed significant statistical differences. A direct correlation was found between hs-CRP, leptin, body mass index and waist circumference, the strongest being with leptin (r=0.568; p<0.001). This trend remained statistically significant, regardless of gender or pubertal age. CONCLUSIONS: Considering the role of leptin, adiponectin and hs-CRP in the genesis of endothelial dysfunction, they may be used in clinical practice for risk stratification, as well as in the assessment of weight control programs

Análise integrada de sistemas de produção de tomateiro com base em indicadores edafobiológicos.

A análise integrada de indicadores edafobiológicos ligados ao manejo do solo constitui uma ferramenta importante para estimar níveis de sustentabilidade do agroecossistema, detectando-se pontos críticos para a devida correção de manejo. Essa ferramenta foi empregada na avaliação de sistemas de produção orgânica e convencional de tomate, em cultivo protegido e a campo aberto, no estado de São Paulo. Tomaram-se como referência solos de mata nativa e/ou pastagem natural, dependendo do local de estudo. Em Serra Negra, o solo sob sistema orgânico apresentou maior capacidade de campo e teor de argila dispersa mais baixo, indicativos da estabilidade dos agregados. No sistema convencional observou-se uma elevada condutividade elétrica, evidenciando a alta disponibilidade de sais solúveis. A análise de componentes principais (ACP) permitiu concluir que há maior grau de similaridade entre o solo sob sistema orgânico e aqueles das bases referenciais, com respeito aos indicadores químicos e biológicos. Constatou-se que C org, N total, polissacarídeos, FDA (hidrólise de diacetato de fluoresceína) e atividade enzimática de desidrogenase estão positivamente relacionados com o sistema orgânico, a mata nativa e a pastagem. Em contrapartida, a saturação por bases (V%), pH, teores de Mn, Mg e Ca, bem como a razão de dispersão estão inversamente relacionadas ao manejo orgânico. Já em Araraquara, os resultados da ACP distinguiram as áreas organicamente cultivadas das matas nativas, principalmente, com base nos indicadores biológicos

Surface circulation in the eastern North Atlantic, from drifters and altimetry

A description of the near-surface circulation and its properties is the result of the analysis of a drifting buoy data set in the eastern North Atlantic between the Iberian Peninsula, the Azores, and the Canary Islands. World Ocean Circulation Experiment-Tropical Ocean-Global Atmosphere experiment drifters equipped with holey sock drogues centered at 15 m depth collected a total of 14.4 years of data. The drifters sampled a rather inhomogeneous velocity field with a weak mean flow regime and eddies of different scales. They meandered southward everywhere in the study region, except in the Iberian coastal transition zone north of 41degreesN where they headed northward. The near-surface mean velocity field obtained from the drifter data set shows all important mean currents, including the poleward Portugal Coastal Countercurrent during the fall, winter, and early spring off western and northern Iberia, the southward Portugal Coastal Current, the slow offshore southward flow of the Portugal Current during the whole year, the southwestward Canary Current, and the eastward Azores Current, which extends to the vicinity of the African coast near the Gulf of Cadiz. Maps of the eddy kinetic energy field were obtained from the drifters and from satellite altimetry. It provides the largest part of the total kinetic energy. The rate of dispersion is estimated from the Lagrangian statistics of the drifting buoys. The dispersion of the drifters in the study region is well modeled by a simple description of eddy diffusion assuming homogeneous turbulence. Ensemble mean diffusivities K and the Langrangian integral length scales and timescales (L and T) were obtained for the zonal and meridional directions. The sea surface temperature measured along the drifter trajectories is used to produce estimates of the eddy diffusivity, which is compared with the diffusivity estimates obtained from the theory of Taylor. The eddy diffusivity is found to be approximately proportional to the eddy kinetic energy. Discrete eddies and meanders were observed using drifters and altimetry in order to map and describe their geographical distribution and characteristics in the eastern North Atlantic

Características fenotípicas de bactérias de nódulos de feijão-caupi nativas de um Argissolo Vermelho Amarelo em Petrolina, PE.

Com este estudo, objetivou-se avaliar as características fenotípicas de bactérias de nódulos de feijão-caupi nativas de um Argissolo Vermelho Amarelo no Município de Petrolina, PE