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The evaluation of the interaction of pollutants in the vadose zone is fundamental for determining the degree of vulnerability of groundwater when transporting contaminants in the soil. The present work presents the interaction of an antibiotic of the type Sulfaziadina in urban soil in the city of Recife. The kinetics and sorption isotherm of Sulfadiazine (SDZ) were determined in a sandy-loam soil of the urban area of the city of Recife. Sorption kinetics and sorption isotherms were performed in for layers of an urban soil profile. Sulfadiazine concentration was determined by high performance liquid chromatography (HPLC). The kinetics studies showed that the sorption was rapid in the first ten hours of the contact period between the soil and the SDZ solution. The equilibrium was reached with 24 hours if interaction in 04 layers. For this soil, SDZ sorption kinetics were reasonably described by a first order model.The second order kinect model presented the best adjustments of sorption kinetics at all depths with R2 values between 0.94 and 0.98. The model that best fit the representation of sorption isotherms was the Linear model. The low KD values (1.3 to 1.9 L.kg-1) indicate high mobility and high risk of groundwater contamination by this compound.

Effluents from textile processes, when discarded of inappropriately, have been shown to be a major environmental concern. In this way, different methods can be used, among them adsorption is an economical and efficient technique in the removal of dyes. Therefore, we propose to analyze the adsorptive capacity of bacterial cellulose (CB) against effluents containing the dye Remazol Black B (RBB). CB was produced by the bacterium Gluconacetobacter hansenii and characterized by the techniques of FTIR, DRX, TGA / DTG and pH (PCZ). The RBB removal tests were initially performed at different pHs. From the best experimental condition, new tests were performed at temperatures of 30, 40, 60 and 100 ± 2 °C, 150 rpm, pH 3.5, using 0.5 g of adsorbent in the concentrations of dye from 25 to 65 mg·L-1. The kinetic study showed that the system balance was achieved in 80 minutes. The experimental data were better described by the pseudo-second order model. The equilibrium results showed that the experimental data fit the Langmuir model (qmax 17.513 mg·g-1). The thermodynamic parameters of adsorption showed that the process is exothermic, not spontaneous and also presented low system randomness. The activation energy (Ea) was 23.8 kJ·mol-1 characterizing physical adsorption. The residual water was not toxic to animal or microbial cells. Bacterial cellulose proved to be a good low-cost adsorbent, easy to acquire and which can be used in the adsorption process.

The consumption of probiotic microorganisms in fermented products has been used for centuries. Lactobacillus spp. is one of the main species studied due to its various beneficial effects on health. This species has a great ability to adapt to hostile environments, produces antimicrobial substances capable of destroying or inhibiting the growth of pathogenic bacteria, and is involved in the digestion of complex carbohydrates not digested by the host. However, there are still some uncertainties and disagreements about the precise biochemical metabolism of lactobacilli. The aim of this article is to review the metabolism and physiological characteristics of lactobacilli for a better understanding of the benefits that these bacteria promote in the host and for the development of strains and probiotic products with higher health benefits.

As indústrias têxteis devem tratar seus efluentes antes do descarte em corpos hídricos. Esse tratamento objetiva majoritariamente a remoção de corantes, cuja interação com o meio ambiente pode causar grandes danos a natureza. A Biossorção tem se mostrado muitas vezes uma técnica econômica e eficaz na remoção de boa parte destes corantes. Deste modo propomos aplicar como biossorvente, o Pennisetum purpureum Schumach., 1827 (Poales: Poaceae) (Capim elefante), para tratar efluentes contendo o corante Índigo Carmim. Os ensaios de remoção do corante foram realizados em batelada nas seguintes condições: variando as temperaturas (30, 40, 60 e 100 ± 2 ºC); agitação constante de 150 rpm; pH 5,5; 0,5 g de biossorvente; e em diferentes concentrações de corante, de 25 a 65 mg·L-1. O mecanismo de biossorção foi bem descrito pelo modelo de Langmuir. A capacidade biossortiva máxima foi de 17,51 mg∙g-1. A investigação termodinâmica indicou que a biossorção é um processo favorável e espontâneo em temperaturas até 60 ºC, acima disso o sistema apresentou uma redução da capacidade biossortiva. Deste modo, a utilização de Pennisetum purpureum Schumach., 1827 (Poales: Poaceae) como biossorvente para a remoção do corante índigo carmim de efluentes têxteis se mostrou uma nova alternativa eficaz e econômica

Sodium percarbonate (SPC, 2Na2CO3∙3H2O2), is a compound that can be used under multiple environmental applications. In this work, SPC was employed as oxidant in the treatment of soil contaminated with diesel oil. The soil samples were collected during the earthmoving stage of RNEST Oil Refinery (Petrobras), Brazil. Then, the samples were air-dried, mixed and characterized. Subsequently, raw soil was contaminated with diesel and treated by photo-Fenton reaction (H2O2/Fe2+/UV). SPC played a significant role in the generation of hydroxyl radicals under the catalytic effect of ferrous ions (Fe2+), hydrogen peroxide (H2O2) and radiation. These radicals provoked the photodegradation of polycyclic aromatic hydrocarbons (PAHs), in the soil remediation. A factorial design 33 was carried out to assess the variables which most influenced the decrease in total organic carbon (TOC). The study was performed with the following variables: initial concentration of [H2O2] and [Fe2+], between 190.0 and 950.0 mmol L−1 and 0.0–14.4 mmol L−1, respectively. UV radiation was supplied from sunlight, blacklight lamps, and system without radiation. All experiments were performed with 5.0 g of contaminated soil in 50.0 mL of solution. The initial concentration of Fe2+ showed the statistically most significant effect. The oxidation efficiency evaluated in the best condition showed a decrease from 34,765 mg kg−1 to 15,801 mg kg−1 in TOC and from 85.750 mg kg−1 to 20.770 mg kg−1 in PAHs content. Moreover, the sums of low and high molecular weight polycyclic aromatic hydrocarbons (LMW-PAHs and HMW-PAHs) were 19.537 mg kg−1 and 1.233 mg kg−1, respectively. Both values are within the limits recommended by the United Sates Environmental Protection Agency (USEPA) and evidenced the satisfactory removal of PAHs from contaminated soil, being an alternative to classic oxidation protocols.

O comportamento hidrodinâmico de solos em cultivo de vazante foi analisado por meio das curvas de retenção θ(h), da condutividade hidráulica K(h), da sorvidade S e do raio característico de poros λm, determinados em dois Neossolos Flúvicos das vazantes dos açudes Cajueiro e Flocos, em Tuparetama, PE. O solo de Cajueiro apresenta uma pequena transição de textura e de densidade do solo, já o de Flocos apresenta uma evidente transição dessas propriedades em profundidade. As curvas de θ(h) foram obtidas pelo ajuste da equação de van Genuchten aos valores de campo (por meio de medidas de tensiômetros e de sonda de nêutrons) e de laboratório (por meio da “câmara de pressão de Richards”). Para determinação de K e S, foram realizados ensaios com o infiltrômetro a disco (0,08 m diâmetro da base), com quatro tensões de fornecimentos, nas profundidades de 0, 0,20, 0,40, 0,60 e 0,80 m. As curvas de θ(h) mostraram boa concordância na faixa de potencial de -30 a -10 kPa, indicando coerência dos dados experimentais. A heterogeneidade hidrodinâmica do solo de Flocos é explicada pela textura e densidade do solo e em Cajueiro é induzida pela distribuição dos tamanhos dos poros. O diâmetro do infiltrômetro, combinado às tensões aplicadas, permitiu caracterizar a matriz porosa da camada argilosa do solo de Flocos.

As indústrias do setor têxtil geram no final de seu processo efluentes com elevada carga orgânica, substâncias tóxicas e cor. O lançamento dessas águas residuais nos corpos hídricos, pode causar sérios problemas do ponto de vista ambiental. Dentre as tecnologias destinadas à remoção de cor destaca-se a biossorção, um processo de captação passiva onde os poluentes depositam-se na superfície de materiais de origem biológica (biossorventes). As vantagens da biossorção em relação aos métodos convencionais de tratamento são a alta seletividade e eficiência, baixo custo e regeneração do material. Considerando esse fato, o objetivo desse trabalho foi produzir um biossorvente misto utilizando o fungo Aspergillus niger van Tieghem, 1867 (Ascomycota: Trichocomaceae) crescido em Pennisetum purpureum Schumach., 1827 (Poales: Poaceae) (capim elefante), para a remoção do corante têxtil preto de remazol B pelo processo de biossorção. Para os ensaios de remoção foi aplicado um planejamento fatorial 25 a fim de analisar a influência das variáveis: pH (2,0, 3,5 e 5,0), agitação (150, 200 e 250 rpm), temperatura (30, 40 e 50 oC), concentração de corante (25, 55 e 85 mg L-1) e quantidade de biossorvente misto (0,5, 1,5 e 2,5 g). A melhor condição obtida no planejamento foi pH 2,0, temperatura de 50 oC, agitação de 150 rpm, concentração de biomassa de 0,5 g e concentração de corante de 25 mg L-1, resultando numa remoção de 96,80%. O estudo permitiu verificar que a utilização de biomassa fúngica associada a um vegetal pode se tornar uma nova alternativa barata e eficiente para o tratamento de efluentes têxteis.

This study describes the extraction, characterisation, purification and conversion of the Moringa oleifera Lamarck oil in biodiesel. The seeds selected were separated into oilseeds grains and seed husks. The oil was extracted from the Moringa oleifera seeds using two different procedures: mechanical pressing and solvent extraction with hexane. The extraction yields of the crude oil were of 11.36% (by mechanical pressing) and of 36.48% (by solvent extraction), respectively. The crude oils were characterised in indexes of acidity, peroxide, iodine and saponification, besides the specific mass, kinematic viscosity, turbidity, and contents of ash and humidity. The crude oil mix formed was submitted to the treatments of degumming, neutralisation, washing and drying. The mixed purified oil was characterised in a similar way to the crude oils, and converted to methyl biodiesel. A homogeneous alkaline transesterification used, 1:6 molar ratio (oil: methanol), at 60 o C, for 60 mins, with KOH as catalyst and mechanical stirring at 300 rpm. The purified biodiesel was characterised in terms of specific mass (869 kg m -3 ; 20 o C), kinematic viscosity (5.5 mm 2 s -1 , 40 o C), ester content (86.2%, in bench scale, and 98.23% in microscale), acidity value (0.43 mg KOH g -1 ) and water content (615.8 mg kg -1 ). DOI: 10.5935/1984-6835.20160063

This study had as aims the extraction, purification and characterization of moringa oil for everyday applications with backing scientific. The average oil yield was of 23.92%, using the techniques: mechanical pressing (11.36%) and by with hexane extraction (35.48%). The oil extracted by pressing was analysed for gas chromatography, revealing a profile of 21.5% of saturated fatty acids and 78.5% of unsaturated fatty acids, having the oleic acid as the major component. The mixed crude oil was refined in four steps: degumming, neutralization, washing and drying. The crude and refined oils were characterised through their acidity index (8.8; 20.5 and 0.2 mgKOH g-1), peroxide index (3.3; 5.4 meqO2 kg-1 and not detected), water content (876.6; 632.0 and 630.2 mg kg-1), turbidity (64.1; 12.6 and 2.1 NTU), specific mass (909.5; 907.2 and 907.0 kg m3), kinematic viscosity (43.6; 39.1 and 41.7 mm2 s-1), high power calorific (39.7; 40. and 39.4 MJ kg-1) and calorific value lower (36.9; 36.9; 37.1 MJ kg-1), and ash content (0.05; 0.05 and 0.007%), respectively. The results show that moringa is a viable and sustainable plant in the use of its oil as raw material for several industries, especially in the food, cosmetic, pharmaceutical and biodiesel industry.

O setor textil produz um efluente bastante toxico, com uma grande concentracao de corantes, os quais sao envolvidos no processo de tingimento. Parte deles sao eliminados na natureza causando danos a fauna e a flora. Diante dessa problematica, metodologias tem sido desenvolvidas afim de tratar esses efluentes antes de serem lancados na natureza. Dentre essas esta a biossorcao, tecnologia que utiliza micro-organismos vivos ou mortos para remocao de contaminantes. A biossorcao se torna bastante atrativa devido aos bons resultados e a facil obtencao de micro-organismos, ja que muitos deles sao facilmente isolados e cultivados. Uma especie alvo de pesquisas em diversos processos industriais devido a sua grande producao de enzimas e produtos de interesse industrial e o Aspergillus niger, um fungo filamentoso largamente encontrado no solo, podendo crescer em diversas culturas vegetais. Neste trabalho foi utilizado como biossorvente a biomassa de Aspergillus niger crescida em capim elefante por 72 h. A massa produzida foi autoclavada a 121oC por 30 min, em seguida filtrada lavada e seca a 65oC ate base seca por 72 h. Com as massas produzidas, foi realizado um planejamento fatorial 2 com o objetivo de estudar o efeito das interacoes: pH, agitacao, temperatura, concentracao de corante e biomassa. A taxa de remocao foi obtida como resposta a essas interacoes. Os resultados do estudo permitiram identificar que os fatores principais temperatura e agitacao nao mostraram significância estatistica numa margem de 95% de confianca. Deve-se destacar ainda, que tanto o fator linear pH quanto o da concentracao de biomassa ocasionaram efeitos negativos na biossorcao do corante, mostrando que tanto o aumento da basicidade do meio quanto o aumento da concentracao de biomassa utilizada diminui o processo biossortivo. A melhor condicao obtida no planejamento foi pH igual a 2,0; temperatura de 50 °C; agitacao de 150 rpm; concentracao de biomassa de 0,5 g e concentracao inicial de corante de 25 mg.L, ocasionando uma remocao de 91,78%.O estudo permitiu verificar que utilizacao de biomassa fungica associada com vegetal pode se tornar uma nova metodologia para tratamento de efluentes texteis.