Influence of mixtures of acenaphthylene and benzo[a] anthracene on their degradation by Pleurotus ostreatus in sandy soil

Purpose Polycyclic aromatic hydrocarbons (PAHs) are a class of organic compounds commonly found as soil contaminants. Fungal degradation is considered as an environmentally friendly and cost-effective approach to remove PAHs from soil. Acenaphthylene (Ace) and Benzo[a]anthracene (BaA) are two PAHs that can coexist in soils; however, the influence of the presence of each other on their biodegradation has not been studied. The biodegradation of Ace and BaA, alone and in mixtures, by the white rot fungus Pleurotus ostreatus was studied in a sandy soil. Materials and methods Experimental microcosms containing soil spiked with different concentrations of Ace and BaAwere inoculated with P. ostreatus. Initial (t 0) and final (after 15 days of incubation) soil concentrations of Ace and BaA were determined after extraction of the PAHs. Results and discussion P. ostreatus was able to degrade 57.7% of the Ace in soil spiked at 30 mg kg−1 dry soil and 65.8% of Ace in soil spiked at 60 mg kg−1 dry soil. The degradation efficiency of BaA by P. ostreatus was 86.7 and 77.4% in soil spiked with Ace at 30 and 60 mg kg−1 dry soil, respectively. After 15 days of incubation, there were no significant differences in Ace concentration between soil spiked with Ace and soil spiked with Ace + BaA, irrespective of the initial soil concentration of both PAHs. There were also no differences in BaA concentration between soil spiked with BaA and soil spiked with BaA + Ace. Conclusions The results indicate that the fungal degradation of Ace and BaA was not influenced by the presence of each other’s PAH in sandy soil. Bioremediation of soils contaminated with Ace and BaA using P. ostreatus is a promising approach to eliminate these PAHs from the environment.

Consolidating preservative-treated wood: Combined mechanical performance of boron and polymeric products in wood degraded by Coniophora puteana

When timber elements in heritage buildings are moderately degraded by fungi and assuming underlying moisture problems have been solved, two actions can be taken: i) use a biocide to stop fungal activity; ii) consolidate the degraded elements so that the timber keeps on fulfilling its structural and decorative functions. The aim of this work is to investigate the mechanical performance of maritime pine wood degraded by fungi after being treated with a biocide followed by impregnation with a polymer product. Three commercially available products were used: a boron water-based biocide, an acrylic consolidant and an epoxy-based consolidant. Treated and consolidated specimens were subjected to mechanical tests: axial compression test (NP 618), static surface hardness (ISO 3350) and bending test (NP 619). Sets of replicates were subjected to an evaporation ageing test (EN 73) after application of the products and also tested for mechanical behaviour. An increase in mechanical strength was observed for both consolidants with no significant influence from the previous use of biocide product. The specimens subjected to ageing showed a slightly better general mechanical performance.

Cutting forces and wear analysis of Si3N4 diamond coated tools in high speed machining

Si3N4 tools were coated with a thin diamond film using a Hot-Filament Chemical Vapour Deposition (HFCVD) reactor, in order to machining a grey cast iron. Wear behaviour of these tools in high speed machining was the main subject of this work. Turning tests were performed with a combination of cutting speeds of 500, 700 and 900 m min−1, and feed rates of 0.1, 0.25 and 0.4 mm rot−1, remaining constant the depth of cut of 1 mm. In order to evaluate the tool behaviour during the turning tests, cutting forces were analyzed being verified a significant increase with feed rate. Diamond film removal occurred for the most severe set of cutting parameters. It was also observed the adhesion of iron and manganese from the workpiece to the tool. Tests were performed on a CNC lathe provided with a 3-axis dynamometer. Results were collected and registered by homemade software. Tool wear analysis was achieved by a Scanning Electron Microscope (SEM) provided with an X-ray Energy Dispersive Spectroscopy (EDS) system. Surface analysis was performed by a profilometer.

Minimização do impacto ambiental do processo de curtume de pele de bovino

O presente trabalho teve como objectivo a minimização do impacto ambiental do processo de curtume da pele de bovino. A indústria de curtumes transforma a pele, material putrescível, em couro, material nobre, termicamente estável e imputrescível. A transformação da pele em couro origina uma carga poluente apreciável quer quanto a efluentes líquidos quer quanto a resíduos sólidos. O fluxo produtivo da indústria de curtumes pode dividir-se em quatro sectores: ribeira, curtume, tinturaria e acabamento, sendo que os três primeiros geram efluentes líquidos com elevada carga poluente. Neste trabalho, foram avaliadas as fases do processo que geram efluentes líquidos: molho, caleiro, curtume e tinturaria. Na avaliação do processo do molho testou-se uma protease e uma lipase contra um molhante e um desengordurante tradicional, agentes químicos normalmente utilizados no molho mas menos biodegradáveis que as enzimas testadas. Salienta-se o bom resultado obtido quanto à eficiência do molho Na avaliação do processo de caleiro testaram-se várias alternativas no sentido da redução da quantidade de sulfureto de sódio utilizada e da minimização da carga poluente. Entre as alternativas, depilação por oxidação, depilação enzimática com e sem destruição do pêlo, elegeu-se a depilação enzimática sem destruição do pêlo que conduziu a resultados com menor impacto ambiental, nomeadamente a redução da % da quantidade de sulfureto de sódio, sendo a redução da carga poluente de 4,19 % de sulfureto, 32.80% de sólidos suspensos totais (SST),27.09% de sólidos totais (ST) e de 76.90% da carência química de oxigénio (CQO) no efluente de caleiro. No processo do curtume da pele é utilizado crómio como agente de curtume em cerca de 80% das peles tratadas, sendo este metal problemático em termos ambientais. No sentido de reduzir a quantidade de crómio utilizada no processo foi realizado um planeamento factorial onde as variáveis a estudar foram a concentração de crómio e a temperatura, tendo este como objectivo observar qual a quantidade mínima de crómio necessária para termos um produto final nas condições desejadas e gerando um menor impacto ambiental. Concluiu-se desenvolvendo um processo que mostra ser possível reduzir a quantidade de sal de crómio de 7% para 5%, além de ter um impacto ambiental claramente menos agressivo nos efluentes de curtume gerado. Este processo quando comparado com o processo tradicional permite a redução de 27% na CQO, 79% nos SST, 11% nos ST e 38% no teor de crómio Na avaliação do processo de tinturaria foi estudado um processo compacto contra o processo tradicional, tendo-se concluído pelo menor impacto ambiental do processo estudado, nomeadamente ao nível da redução do consumo de água e da carga poluente gerada. A comparação dos dois processos, no que respeita à carga poluente gerada, permitiu concluir por uma redução de 39% da CQO, 50% dos SST, e 12% dos ST quando aplicado o processo compacto Por fim foi feita uma avaliação do impacto ambiental do efluente global gerado pelos processos considerados com menor impacto ambiental contra o processo tradicional, normalmente aplicado na indústria. A aplicação do conjunto dos processos desenvolvidos, quando comparada com a aplicação do conjunto dos processos tradicionais, mostra uma redução de 1% no sulfureto, 40% na CQO, 60 % nos SST, 42 % no crómio e 11% nos ST, mostrando claramente que é possível reduzir a carga poluente da indústria de curtumes atuando no processo. Este trabalho mostrou a importância de atuar no processo para minimizar os custos de tratamento e mesmo de investimento dos efluentes da indústria de curtumes. Importa salientar que os processos desenvolvidos necessitam de validação a uma escala semi-industrial.

Aplicação da teoria das opções reais em análise de projetos estratégicos: um estudo de caso sobre o valor da opção de prosseguir com os investimentos no programa de desenvolvimento de submarinos da Marinha do Brasil

Dissertação de mestrado em Estudos de Gestão

Continuous fungal treatment of non-sterile veterinary hospital effluent: pharmaceuticals removal and microbial community assessment

Source point treatment of effluents with a high load of pharmaceutical active compounds (PhACs), such as hospital wastewater, is a matter of discussion among the scientific community. Fungal treatments have been reported to be successful in degrading this type of pollutants and, therefore, the white-rot fungus Trametes versicolor was applied for the removal of PhACs from veterinary hospital wastewater. Sixty-six percent removal was achieved in a non-sterile batch bioreactor inoculated with T. versicolor pellets. On the other hand, the study of microbial communities by means of DGGE and phylogenetic analyses led us to identify some microbial interactions and helped us moving to a continuous process. PhAC removal efficiency achieved in the fungal treatment operated in non-sterile continuous mode was 44 % after adjusting the C/N ratio with respect to the previously calculated one for sterile treatments. Fungal and bacterial communities in the continuous bioreactors were monitored as well.

Aproximación al diseño de sistemas de bio-reactores para la delignificación de materiales lignocelulósicos y para la decontaminación de suelos y efluentes. Approximation to the design of bio-reactors systems for the delignificación of lignocellulosic materials and for the decontamination of soil and effluents

Los materiales lignocelulósicos residuales de las actividades agroindustriales pueden ser aprovechados como fuente de lignina, hemicelulosa y celulosa. El tratamiento químico del material lignocelulósico se debe enfrentar al hecho de que dicho material es bastante recalcitrante a tal ataque, fundamentalmente debido a la presencia del polímero lignina. Esto se puede lograr también utilizando hongos de la podredumbre blanca de la madera. Estos producen enzimas lignolíticas extracelulares fundamentalmente Lacasa, que oxida la lignina a CO2. Tambien oxida un amplio rango de sustratos ( fenoles, polifenoles, anilinas, aril-diaminas, fenoles metoxi-sustituídos, y otros), lo cual es una buena razón de su atracción para aplicaciones biotecnológicas. La enzima tiene potencial aplicación en procesos tales como en la delignificación de materiales lignocelulósicos y en el bioblanqueado de pulpas para papel, en el tratamiento de aguas residuales de plantas industriales, en la modificación de fibras y decoloración en industrias textiles y de colorantes, en el mejoramiento de alimentos para animales, en la detoxificación de polutantes y en bioremediación de suelos contaminados. También se la ha utilizado en Q.Orgánica para la oxidación de grupos funcionales, en la formación de enlaces carbono- nitrógeno y en la síntesis de productos naturales complejos. HIPOTESIS: Los hongos de podredumbre blanca, y en condiciones óptimas de cultivo producen distintos tipos de enzimas oxidasas, siendo las lacasas las más adecuadas para explorarlas como catalizadores en los siguientes procesos:  Delignificación de residuos de la industria forestal con el fin de aprovechar tales desechos en la alimentación animal.  Decontaminación/remediación de suelos y/o efluentes industriales. Se realizarán los estudios para el diseño de bio-reactores que permitan responder a las dos cuestiones planteadas en la hipótesis. Para el proceso de delignificación de material lignocelulósico se proponen dos estrategias: 1- tratar el material con el micelio del hongo adecuando la provisión de nutrientes para un desarrollo sostenido y favorecer la liberación de la enzima. 2- Utilizar la enzima lacasa parcialmente purificada acoplada a un sistema mediador para oxidar los compuestos polifenólicos. Para el proceso de decontaminación/remediación de suelos y/o efluentes industriales se trabajará también en dos frentes: 3) por un lado, se ha descripto que existe una correlación positiva entre la actividad de algunas enzimas presentes en el suelo y la fertilidad. En este sentido se conoce que un sistema enzimático, tentativamente identificado como una lacasa de origen microbiano es responsable de la transformación de compuestos orgánicos en el suelo. La enzima protege al suelo de la acumulación de compuestos orgánicos peligrosos catalizando reacciones que involucran degradación, polimerización e incorporación a complejos del ácido húmico. Se utilizarán suelos incorporados con distintos polutantes(por ej. policlorofenoles ó cloroanilinas.) 4) Se trabajará con efluentes industriales contaminantes (alpechínes y/o el efluente líquido del proceso de desamargado de las aceitunas). The lignocellulosic raw materials of the agroindustrial activities can be taken advantage as source of lignin, hemicellulose and cellulose. The chemical treatment of this material is not easy because the above mentioned material is recalcitrant enough to such an assault, due to the presence of the lignin. This can be achieved also using the white-rot fungi of the wood. It produces extracellular ligninolitic enzymes, fundamentally Laccase, which oxidizes the lignin to CO2. The enzyme has application in such processes as in the delignification of lignocellulosic materials and in the biobleaching of fibers for paper industry, in the treatment of waste water of industrial plants, in the discoloration in textile industries, in the improvement of food for ruminants, in the detoxification of polutants and in bioremediation of contaminated soils. HYPOTHESIS: The white-rot fungi produce different types of enzymes, being the laccases the most adapted to explore them as catalysts in the following processes:  Delignification of residues of the forest industry in order to take advantage of such waste in the animal feed.  Decontamination of soils and / or waste waters. The studies will be conducted for the design of bio reactors that allow to answer to both questions raised in the hypothesis. For the delignification process of lignocellulosic material they propose two strategies: 1- to treat the material with the fungi 2-to use the partially purified enzyme to oxidize the polyphenolic compounds. For the soil and/or waste water decontamination process, we have: 3- Is know that the enzyme protects to the soil of the accumulation of organic dangerous compounds catalyzing reactions that involve degradation, polymerization and incorporation to complexes of the humic acid. There will be use soils incorporated into different pollutants. 4- We will work with waste waters (alpechins or the green olive debittering effluents.

A disponibilidade do potássio da "leucita de Poços de Caldas", estudada por meio do arroz

In order to know potassium availability in "leucita de Poços de Caldas" from Poços de Caldas, Minas Gerais, a Mitscherlich pot experiment was set up. The pots were filled with 6 kilograms of sieved (4 mm) "Terra Roxa Misturada" soil. Rice (Oryza sativa, L.), Dourado Agulha variety was the testing plant. Doses of potassium referred to are 1,5 g (as K(2)0) from both KCl and "leucita de Poços de Caldas". There were 6 treatments, with 3 repetitions, as follows: 1) Control; 2) NP + 1 dose K (KCl); 3) NP + 2 doses K (KCl)); 4) NP + 3 doses K (KCl); 5) NP + 1 dose K (leucita); 6) NP + 2 doses K (leucita) and 7) NP + 3 doses K (leucita). Each pot received 50 seeds. Five days after germination the seedlings were thinned to 35. Harvesting took place 4 months after germination. Potassium (as KCl) promoted an increase in yield of both stalk and grain as compared with control. Potassium content in the leaves was also higher in all treatment in which KCl was supplied. Potassium, as "leucita de Poços de Caldas» did not show any favorable effect on both stalk and grain yield and on its content in the leaves.

A absorção do manganês pela cana de açúcar, Co 419, em função da idade

In this paper the authors have studied the manganese absorption by the sugar cane plant, variety Co 419, in samples cut monthly, from the 6th to 15th month of life in the climate prevailing at Piracicaba, State of Sao Paulo, Brazil. From October to February (6 th to 10 th month of the plant life), which coincided with the rainy season, the manganese content was higher in the stalk than in the leaves, for both treatments, fertilized and unfertilized. There was a sharp decrease in manganese content in the stalks, after February, in both reatments. In the leaves there was little variation in manganese content throughout the plant tissue. The stalks from the unfertilized plots had a larger variation in manganese content, specially from the 6 th to the 10 th month. In the leaves of the sugar cane from the unfertilized plots, the manganese content varied from 116 to 220 ppm, whereas in the fertilized treatments thire was a variation from 150 to 220 ppm. From these results, althoug not being a foliar analyses, and considering the easy availability of manganese in acid soils, there must be enough of it, if we consider 40 ppm (EVANS, 1955) as a minimum for healthy plants.

A amostragem da cana-de-açúcar para determinações tecnológicas

The authors carried out 3 experiments on the sampling of sugar cane for technological determinations, one with each of the varieties Co 419, CB 40-69 and CB 41-58, in Piracicaba, State of São Paulo, Brasil. The main intent of the project was to compare 2 methods of sampling, namely: 1) Method A, where the sample is a hill (CATANI et al, 1959) or, more generally, 20 stalks all together in a randomly selected point of the furrow; 2) Method B, where 20 stalks are taken, from 20 points evenly spread but on the whole plot. Coefficients of variation for 20 stalk samples Variety Characteristic 20 stalks per hill 1 stalk per hill Brix 4.8% 1.9% Pol 6.4% 2.5% CB 40-69 Coefficient of purity 2.1% 0.83% Available sucrose 7.3% 2.7% Weight 6.6% 6.9% Brix 5.3% 1.8% Pol 7.6% 2.6% Co 419 Coefficient of purity 2.9% 1.0% Available sucrose 8.6% 3.0% Weight 21.2% 6.5% Brix 2.8% 1.4% Pol 4.1% 1.9% CB 41-58 Coefficient of purity 1.8% 0.8% Available sucrose 5.0% 2.2% Weight 10.9% 6.2% For the 3 varieties studied and for the data on Brix, pol, coefficient of purity, available sucrose and weight, analyses of variance were carried out. Further computations led to the following coefficients of variation. For available sucrose, which is probably the most important characteristic studied, the average coefficient of variation for the 3 varieties was 2.7%, for the case of method B, that is, 20 stalk samples, one stalk per hill. Assuming this coefficient of variation, in a trial with 5 treatments and 6 replications, in randomised blocks, the least significant difference among treatment means, at the 5% level, would be 4.7% of available sucrose by Tukey's test, and 3.3% by the t test. For the case of method A the average coefficient of variation is 7.0% and, in similar conditions, the least significant difference would be 15.1% by Tukey's test, and 12.1% by the t test. Since differences of available sucrose among treatments in experiments with fertilizers seldom are higher than 3 or 4% of the mean (PIMENTEL GOMES & CARDOSO, 1958), method B with a 20 stalk sample per plot gives more or less the minimum amount of cane to be sampled for technological determinations. In experiments with varieties, however, where differences may be assumed to be higher, a sample of 10 to 20 stalks one per hill, can be enough.

Influência do desponte sôbre a composição do colmo e do caldo da cana-de-açúcar: III. Var. CB 41-76

I. This paper deals with an experiment carried out to evaluate the effect of sugar cane upper end on the composition of the stalks and juice of sugar cane harvest as a raw material for the sugar industry. The variety studied was CB 41-76. The data were collected from plant cane at intervals of a two weeks, always from the same field, from a small central area of 3.000 square meters approximately, 60 stalks were cut in each occasion, randomly chosen from the whole area. They were afterwards separated into three groups of 20 stalks one for each of the treatments, namely: a) Complete stalk, with no leaves or sheaths. b) Stalks harvested by the technique of REYNOSO, that is, as usually done in practice. c) Stalks with the tops completely cut out, that is, cut by the techinique of REYNOSO and then with 3 other top internodes eliminated. The treatments caused significant differences on the weight of cane and coefficient of purity of juice, but the percentual differences between the average treatments a and c is 13% and 2%, respectively. II. Treatment differences for cane pol, cane fibre, brix, juice pol, reducing sugars, juice ashes, glucose coefficient, saline coefficient and available sucrose (pol) per cent were not significant. III. Time of harvest was an important factor affecting the composition of the cane and the juice. This paper shows that there is no sound basis for the heavy fines applied some sugar mills to planters who do not cut low enough the tops of the cane stalks.

Cultivo de pimiento en invernadero. Influencia de la humedad ambiental y de la salinidad

El cultivo de pimiento se caracteriza por presentar una alta susceptibilidad a la necrosis apical (Blossom-end-rot, BER). El BER es una fisiopatía originada por una deficiencia de calcio durante el estado inicial de desarrollo del fruto. Los altos valores de radiación y déficit de presión de vapor (DPV) característicos de la zona mediterránea afectan considerablemente a la transpiración y a la absorción de minerales favoreciendo la aparición de BER. En el Institut de Recerca i Tecnologia Agroalimentàries (IRTA) se han realizado dos experiencias en cultivo sin suelo de pimiento con el objetivo de evaluar el efecto de la humedad ambiental y la salinidad sobre la producción y calidad. Se realizaron dos ensayos comparando la producción y la incidencia de BER bajo condiciones climáticas diferentes y evaluando la influencia de la salinidad de la solución nutritiva sobre estos mismos parámetros. Los resultados obtenidos muestran la importancia del control del clima y, en concreto, de la humedad del invernadero sobre la aparición de BER. La incidencia de BER se incrementa un 24% en condiciones de baja humedad respecto al tratamiento control con humedad relativa elevada. Respecto a la salinidad, en condiciones de humedad elevada, el incremento de la conductividad de la solución nutritiva de 2 a 4 µS/cm implica un aumento de más del 8% de la incidencia de BER. Si las condiciones ambientales son más extremas, bajos valores de humedad, el aumento en la incidencia de BER debido a la salinidad de la solución nutritiva puede alcanzar valores del 68%.

Avaluació del creixement del fong ligninolític Trametes versicolor sobre diferents suports sòlids per a l'aplicació en tractaments de bioremediació

Els fongs de podridura blanca (WRF - de l'anglès: White-rot fungi) són de gran interès en l'àmbit de la bioremediació per la seva capacitat de degradar la lignina. La lacasa, un dels enzims extracel·lulars que aquests fongs excreten per degradar la lignina, pot ser utilitzada per degradar els contamiants presents en una matriu donada. Trametes versicolor ha estat estudiat per la seva capacitat de produïr aquest enzim en rersidus agrícoles com a substrats. Un primer triatge basat en la producció de CO2, la mesura de l'activitat lacasa i la quantificació de l'ergosterol han permés seleccionar els substrats on es donava un major poder oxidatiu dels cultius inoculats amb T. versicolor. Els posteriors experiments de colonització de sòls, on es monitoritzava l'activitat lacasa i l'ergosterol, han mostrat que T. vesicolor és capaç de colonitzar sòls i que té una major activitat lacasa en condicions no estèrils. També h'ha provat, mitjançant el test ND24, que T. versicolor és capaç de degradar un contaminant emergent, el naproxè, en sòls estèrils i no estèrils esmenats amb residus agrícoles.

Adaptation to larval malnutrition does not affect fluctuating asymmetry in Drosophila melanogaster

Both stress during development and response to directional selection were proposed to lead to reduced developmental stability of an organism, commonly measured as fluctuating asymmetry. Here, we investigated the direct physiological (plastic) effect of larval malnutrition and the effect of evolutionary adaptation to this form of stress on developmental stability, measured as fluctuating asymmetry of several wing measurements. The measurements were made on female Drosophila melanogaster from populations which, in the course of 84 generations of experimental evolution, adapted to malnutrition and from non-adapted controls, raised either under standard conditions or under nutritional stress. We detected no changes in the levels of fluctuating asymmetry as either a plastic or an evolutionary response. Thus, neither nutritional stress within lifetime nor directional selection it imposes seems to affect developmental stability in flies.

Characterization of the hcnABC gene cluster encoding hydrogen cyanide synthase and anaerobic regulation by ANR in the strictly aerobic biocontrol agent Pseudomonas fluorescens CHA0.

The secondary metabolite hydrogen cyanide (HCN) is produced by Pseudomonas fluorescens from glycine, essentially under microaerophilic conditions. The genetic basis of HCN synthesis in P. fluorescens CHA0 was investigated. The contiguous structural genes hcnABC encoding HCN synthase were expressed from the T7 promoter in Escherichia coli, resulting in HCN production in this bacterium. Analysis of the nucleotide sequence of the hcnABC genes showed that each HCN synthase subunit was similar to known enzymes involved in hydrogen transfer, i.e., to formate dehydrogenase (for HcnA) or amino acid oxidases (for HcnB and HcnC). These similarities and the presence of flavin adenine dinucleotide- or NAD(P)-binding motifs in HcnB and HcnC suggest that HCN synthase may act as a dehydrogenase in the reaction leading from glycine to HCN and CO2. The hcnA promoter was mapped by primer extension; the -40 sequence (TTGGC ... ATCAA) resembled the consensus FNR (fumarate and nitrate reductase regulator) binding sequence (TTGAT ... ATCAA). The gene encoding the FNR-like protein ANR (anaerobic regulator) was cloned from P. fluorescens CHA0 and sequenced. ANR of strain CHA0 was most similar to ANR of P. aeruginosa and CydR of Azotobacter vinelandii. An anr mutant of P. fluorescens (CHA21) produced little HCN and was unable to express an hcnA-lacZ translational fusion, whereas in wild-type strain CHA0, microaerophilic conditions strongly favored the expression of the hcnA-lacZ fusion. Mutant CHA21 as well as an hcn deletion mutant were impaired in their capacity to suppress black root rot of tobacco, a disease caused by Thielaviopsis basicola, under gnotobiotic conditions. This effect was most pronounced in water-saturated artificial soil, where the anr mutant had lost about 30% of disease suppression ability, compared with wild-type strain CHA0. These results show that the anaerobic regulator ANR is required for cyanide synthesis in the strictly aerobic strain CHA0 and suggest that ANR-mediated cyanogenesis contributes to the suppression of black root rot.