No description available.

<p> The study of proteasome is a rapidly evolving field with multifaceted implications in neuroscience, aging, and cancer. Recent developments structural biology of the proteasome machinery has catapulted the drug discovery and targeted protein degradation. The success of proteasome inhibitors like Bortezomib and Ixazomib has also led to new interests in developing more precise inhibitors for the various proteasome isoforms. Proteasome activation is a relatively new field, and much has to be done in the field. The 20S CP is an emerging target in chemical biology and drug discovery for its implications in maintaining protein homeostasis and immune regulation. The central theme of the thesis is to study the proteasome in cellular contexts to develop new chemical biology tools to study the proteasome and its modulation by small molecules and probes in cellular contexts to ameliorate protein accumulation-mediated neurodegeneration </p>

Stink bugs are major pests of agricultural crops throughout Virginia and much of the United States. Knowledge of the biology, the species complex, and insecticide susceptibility can improve management. A survey was conducted in Virginia to determine the species complex in soybean and cotton and to monitor for nonnative species. Seven stink bug species were identified. Acrosternum hilare (Say) and Euschistus servus (Say) were the most common. Two sampling methods, the sweep net and the beat sheet, were assessed in soybean and cotton. There was less variability with the sweep net method compared to the beat sheet method. Laboratory bioassays and field trials were conducted to evaluate the toxicity and efficacy of selected conventional and organic insecticides against A. hilare and E. servus. In bioassays with conventional insecticides, A. hilare adults and nymphs were susceptible to all pyrethroids tested. Generally, the neonicotinoids, dinotefuran and clothianidin, were more toxic to A. hilare, while thiamethoxam and acetamiprid were more toxic to E. servus. In soybean field efficacy trials, dinotefuran performed comparably to the organophosphates and pyrethroids. Laboratory bioassays with organic insecticides resulted in moderate to high levels of mortality, and in antifeedant and repellency responses. Likewise, soybean field trials indicated that a single application can reduce stink bug numbers for up to two days after treatment; however in tomato field trials multiple weekly applications did not result in significant reductions in stink bug damage. A weather model to predict abundance of A. hilare adults was developed using weekly black light trap catch data collected from 1990 to 2007 at a single location. The two weather variables that resulted in a significant model were days below freezing and mean monthly precipitation from January to April. The model was validated by correlating five independent data sets to predicted weekly trap catch. Mean trap catch plotted over time showed three peaks. In accordance with A. hilare developmental rates, the peaks indicated that two generations and a partial third occur in Virginia. Cumulative trap catch estimated from the 18-yr trap catch mean showed that 10, 50, and 90% of the total seasonal catch should occur by 153, 501, and 1066 degree days, respectively. / Ph. D.

Intensively managed forests of the Southern United States are among the most important sources of wood fiber and timber in this country. There is a great deal of concern that disturbances associated with trafficking by heavy machinery might diminish long-term soil-site productivity. However, determining the effect of harvesting disturbance and silvicultural treatments on the long-term productivity of pine plantations is difficult because, in addition to harvesting effects, growth distributions are affected by changes in climate, silviculture, and genetics. The primary objectives of this study were to determine (1) whether logging disturbances under operationally realistic circumstances affect soil quality, hydrologic function, and loblolly pine (Pinus taeda L.) productivity on wet pine flats, and (2) whether intensive forest management practices mitigate disturbance effects if they exist. Three 20-ha loblolly pine plantations located on wet pine flats in South Carolina were subjected to combinations of wet- and dry-weather harvesting and mechanical site preparations. Changes in soil-site productivity after five years were evaluated using a new rank method. The key advantage of the rank change method is that it is largely independent of the confounding factors (e.g. genetics, silvicultural practices, and climate) that affect comparisons of tree growth and soil quality between growth cycles. After five years, loblolly pine site indexes (base age 25) ranged between 13 and 33 m, and production ranged between 0.5 and 95 Mg ha-1. Soil bulk densities increased from 1.15 to as high as 1.44 g cm-3 after harvesting; by age 7 years it had decreased to approximately 1.25 g cm-3. At the sub-stand scale (0.008 ha), visually assessed soil physical and harvesting residue disturbances had little influence on relative changes in soil-site productivity after five years. Factors that specifically reflect site drainage were the most influential on changes in productivity. At the operational scale (3.3 ha), there were no differences between wet- and dry- harvested sites as long as bedding was applied as a site treatment. These results indicate that when standard site preparation is employed, fertile, wet pine flats such as these are resilient in that they recover from severe, but operationally realistic, harvesting disturbances. / Ph. D.

Systena frontalis (F.) (Coleoptera: Chrysomelidae), the red headed flea beetle (RHFB), is a ubiquitous pest of ornamental nursery crops in the eastern United States. Defoliation by adults renders plants unsaleable. Control costs and economic losses from injured plants have become a top concern among Virginia nurseries in the past decade. Current management tactics include spraying insecticides up to three times a week during the adult active season. The frequent use of insecticides poses a risk to the environment, non-target organisms, and evolution of resistance within the targeted beetle population. To develop a sustainable pest management program, more information is needed to understand pest biology, quantify the injury potential, and explore control tactics. Methods to monitor this beetle were used to observe peak activity throughout the growing season as well as the adult daily activity levels. There were three observed generations with population peaks in late June, late July, and late August into early September. Within the scale of one day, adult beetles were found to be diurnal with peaks in activity in the middle of the day. These findings will inform growers of the most efficient times to scout and spray, ultimately reducing insecticide usage. Quantification of feeding damage to individual leaves, the entire plant, and preference between older and newer growth may relate plant injury with specific population densities. The use of phenyl ethyl alcohol as an attractant lure, was explored to bolster pest control. Finally, insecticide bioassays were performed to compare those currently used to others yet untested. / Master of Science in Life Sciences / The red headed flea beetle (RHFB) is an important pest of ornamental crops in open-field nurseries along the Eastern United States. Defoliation caused by adult feeding renders plants unsellable. Japanese hollies, hydrangeas, and sweetspire iteas are among the most affected plants. Infested nurseries suffer severe economic losses due to insecticide costs and plant inventory reductions. Growers are spraying insecticides up to three times a week to manage RHFB. Frequent use of insecticides poses risks to the environment non-target organisms. This study will help improve control tactics for this pest and potentially minimize non-target effects by reducing insecticide usage. Understanding when beetles are active throughout the day, and throughout the growing season, may inform timing of scouting and insecticide sprays to maximize effectiveness. With populations highest in late June, late July, and late August, RHFB is estimated to have three generations per year. Adults are most active in the middle of the day and sedentary at night. It was observed how different densities of beetles cause injury to individual leaves and entire plants, and compared feeding preference on older versus newer growth. Chemical control tactics were explored including insecticides labeled and not labeled for RHFB such as iscycloseram. Finally, the effectiveness of phenyl ethyl alcohol as an attractant lure for RHFB was assessed and found ineffective within the open-field nursery ecosystem.

Made available in DSpace on 2017-07-10T18:08:06Z (GMT). No. of bitstreams: 1 Ariadine R C de Souza.pdf: 3448582 bytes, checksum: c9a134accab4a823b60c11ba4b8a1727 (MD5) Previous issue date: 2016-02-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research project aimed the evaluation of the antibiotic ciprofloxacin hydrochloride (CIP (HCl)) removal in solution, by applying an electrocoagulation (EC) process. The CIP (HCl) solution was prepared with an initial concentration of 25 mg L-1 CIP (HCl) in distilled water. The experiments were conducted in an EC reactor in laboratory scale, consisting of aluminum electrodes. In order to get the best reactor operating parameters, regarding its variables (initial pH, current intensity and time of electrolysis), a response surface methodology was applied based on a complete experimental design (CED) 3³. The CIP (HCl) concentration was monitored by high-performance liquid chromatography (HPLC), and the mineralization was accompanied based on the reduction of total organic carbon (TOC). To obtain the operating conditions considered ideal for the operation of the EC reactor, a predicted second-order model was adjusted to the experimental responses and then validated by ANOVA. The influence of each reactor operating parameter was individually investigated, in a wider range than the one studied in the CED. Thus, the optimal values for each operating parameters were initial pH at 9.0 and current intensity of 0.8 A. From these responses, a kinetic analysis of the EC process was performed, reaching a rapid reduction of CIP (HCl) in the first minutes of electrolysis, stabilizing at 99% in times greater than 40 minutes. The toxicity of the treated solution was measured by applying ecotoxicity and phytotoxicity bioassays, taking as bioindicators Artemia salina and Lactuca sativa, respectively. The toxicity test using Artemia salina was susceptible to the type of remaining toxic compounds formed after the CIP (HCl) solution treatment of short duration. Furthermore, the remaining toxicity after 75 min of EC became nearly harmless to this bioindicator. On the other hand, the bioindicator Lactuca sativa was not susceptible to the action of these compounds at any treatment time. Due to the possible presence of the organic compound CIP (HCl) at a low concentration in the solutions treated by high electrolysis time, an antimicrobial activity analysis using the microorganisms S. aureus and E. coli was applied. The antimicrobial activity of the solution over 40 min electrolysis treatments was almost null or absent. In order to identify the CIP (HCl) in the sludge generated during the process, an X-ray diffraction (XRD) analysis was applied. CIP (HCl) was not identified in the residual sludge or the treated solution, indicating degradation of the compound during the treatment, possibly by electro-oxidation reactions. Therefore, the electrocoagulation provided the degradation of CIP (HCl) pollutant maintaining the treated solution free of toxicity and adverse biological effects to aquatic biota enabling their disposal in the environment, if the ideal operational conditions are maintained (initial pH 9.0, current density 0.8 A and electrolysis time of 75 min). / Este projeto de investigação visa avaliar a remoção do antibiótico cloridrato de ciprofloxacina (CIP(HCl)) em solução, por meio de um processo de eletrocoagulação (EC). A solução de CIP(HCl) foi preparada com concentração inicial de 25 mg L-1 de CIP(HCl) em água destilada. Os experimentos foram realizados em um reator de EC, em escala laboratorial, constituído por eletrodos de alumínio. A fim de obter os melhores parâmetros de operação do reator em relação as suas variáveis (pH inicial, intensidade de corrente e tempo de eletrólise), uma metodologia de superfície de resposta foi aplicada baseada em um planejamento experimental completo (PEC) 3³. A concentração de CIP(HCl) foi monitorada por cromatografia líquida de alta eficiência (CLAE) e sua mineralização foi baseada na redução do carbono orgânico total (COT). Para obtenção das condições operacionais consideradas ideais para o funcionamento do reator de EC, um modelo previsto de segunda ordem foi ajustado às respostas experimentais e em seguida validado pela ANOVA. A influência de cada parâmetro de funcionamento do reator foi investigada individualmente em uma faixa de estudo mais ampla do que a avaliada PEC. Desta maneira, os valores considerados ideais para cada parâmetro operacional foram: pH inicial 9,0 e intensidade de corrente 0,8 A. A partir destas respostas, foi realizada uma análise cinética do processo de EC, onde se atingiu uma rápida redução de CIP(HCl) nos primeiros minutos de eletrólise, se estabilizando em 99% em tempos superiores a 40 min. A toxicidade da solução tratada foi avaliada aplicando bioensaios de ecotoxicidade e de fitotoxicidade, tomando como bioindicadores a Artemia salina e a Lactuca sativa, respectivamente. O teste de toxicidade utilizando a Artemia salina foi susceptível aos compostos tóxicos remanescentes formados após o tratamento da solução de CIP(HCl) de curta duração. Além disso, a toxicidade após 75 min de EC se tornou quase inócua a este bioindicador. Por outro lado, o bioindicador Lactuca sativa não foi susceptível à ação dos compostos tóxicos remanescentes a qualquer tempo de tratamento. Devido a possível presença do composto orgânico CIP(HCl) em baixas concentrações, nas soluções tratadas por elevados tempos de eletrólise, aplicou-se a análise de atividade antimicrobiana utilizando os micro-organismos S. aureus e E. coli. A atividade antimicrobiana da solução com tratamentos acima de 40 min de eletrólise foi ausente. Visando a identificação da CIP(HCl) no lodo gerado durante o processo, análises de difração de raio-X (DRX) foram realizadas. Não se identificou CIP(HCl) no lodo residual nem na solução tratada, indicando a degradação do composto durante o tratamento, possivelmente por reações de eletroxidação. Portanto, o processo de EC proporcionou a degradação do poluente CIP(HCl), mantendo a solução tratada isenta de toxicidade e de efeitos biológicos adversos à biota aquática possibilitando seu descarte no meio ambiente, se mantidas as condições operacionais ideais para o funcionamento do reator (pH inicial 9,0, intensidade de corrente 0,8 A e tempo de eletrólise de 75 min).

Thesis (MSc)--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Landfarming is a widely used method for the disposal of contaminants in the petrochemical industry. It involves ploughing the contaminants into the top soil layer allowing biological breakdown. A historically landfarmed site was identified at a South African petrol refinery. The refinery used to dispose so-called American Petroleum Institute (API) -sludge onto a landfarming site. API-sludge consisted of a mixture of oil and water soluble contaminants originating from a process of separating refinery waste from reusable water and oil. Landfarming on this site was discontinued after excessive quantities of sludge were ploughed into the soil over time and it became obvious that effective biodegradation could not take place. An environmental assessment had to be carried out to assess to what extent the soil has recovered from the contamination and after remediation was done over time. Bioassays together with chemical analyses were executed to determine the level of pollutants in the soil and to assess the integrated effects of their bioavailable fractions. The landfarming site of the refinery was divided into two sections namely, a more contaminated north-site and less contaminated south-site. Soil samples were collected from both sites as well as from an off-site (control site). The soils were analysed physically, chemically and used in the bioassays. Two additional control soils were also used, OECD-soil and LUFA2.2 soil. Chemical analysis of the site soils showed the presence of heavy metals and high levels of diesel range organic hydrocarbons. The north-site had higher levels of contaminants compared to the south-site. Three species of soil organisms were used in standardised tests: Eisenia andrei, Enchytraeus doerjesi and Folsomia candida were exposed to the respective soils to study their survival, growth, reproduction success and avoidance behavior. Exposures to both site-soils were not acutely toxic to any organisms. F. candida had a decrease in juvenile production in both north- and south-site soils (289.42 ± 58.62 and 253.33 ± 122.94 respectively) compared to the control soil (479.89 ± 30.42). E. doerjesi showed an increase in produced juveniles exposed to north- and south-site soil (339.75 ± 76.92 and 414.00 ± 17.78 ) compared to control soil (57 ± 34.39). E. andrei had similar cocoon production when exposed to south-site soil than in off-site soil (19.00 ± 5.3 and 18.5 ± 9.7 respectively) but significantly less in north-site soil (1.25 ± 0.7). Only E. doerjesi showed avoidance of north-site soil. To determine the sensitivity of the organisms to the API-sludge, they were exposed to concentration series of API-sludge-spiked control soils. The effect concentrations were calculated as the concentration of API-sludge that will decrease the studied endpoints by 50% of the control soil (EC50). The EC50s varied for each species exposed in the different control soils showing that the toxicity of the API-sludge is to a certain extent dependent on the physical soil properties of the substrate. The reproduction of F. candida were most sensitive to the API-sludge in off-site soil (EC50 = 90 mg/kg) and the E. doerjesi the least sensitive in LUFA2.2 soil (EC50 = 36000 mg/kg). Five plant species were exposed to API-sludge-spiked potting soil and the germination success, early growth rate and biomass were studied. The plants were not as sensitive to API-sludge as the soil animals. Lettuce and grass were affected the most by API-sludge and beans were the most resilient species. With the addition of low levels API-sludge to the substrate, the growth rate of beans was stimulated. This study showed that the south-site has been successfully remediated and most soil organisms exposed to these soils were not affected by the levels of toxicants present. However, exposures to north-site soil still had negative effects on soil organisms. It is recommended that hydrocarbon contamination should be further remediated in the north-site soil before landfarming should be allowed to continue. / AFRIKAANSE OPSOMMING: Ploegverwerking is ‘n algemene remediëringsmetode vir die verwerking van afvalmateriaal in petrochemiese industrieë. Dit behels die inploeg van toksiese afvalmateriaal in die boonstegrondlaag sodat dit biologies afgebreek kan word. ‘n Voorbeeld van ‘n histories ploegverwerkte grondstuk is geidentifiseer by ‘n Suid-Afrikaanse olieraffinadery. Die raffinadery het in die verlede van die grondstuk gebruik gemaak om sogenaamde Amerikaanse Petroleum Instituut-slik (API-slik) daarin te ploeg. Die API-slik bestaan uit ‘n mengsel van olie- en wateroplosbare kontaminante afkomstig van die proses waardeur die raffinadery se afvalprodukte van hernubare water en olie geskei word. Nadat oormatige konsentrasies slik in die grond ingewerk is en bioremediasie nie meer doeltreffend kon voortgaan nie, is die ploegverwerking gestaak. ‘n Omgewingimpakstudie moes uitgevoer word om te bepaal tot watter mate die grond herstel het nadat remediasie oor tyd uitgevoer is. Toksisiteitstoetse en chemiese analises is uitgevoer om die vlakke van besoedeling sowel as die biobeskikbare fraksie daarvan in die grond te bepaal. Die ploegverwerkte area van die raffinadery is in twee verdeel naamlik, ‘n meer gekontamineerde noordelike area en ‘n minder gekontamineerde suidelike area. Grondmonsters is van die onderskeie areas asook van ‘n ongekontamineerde veld (as kontrole) naby die ploegverwerkte area versamel Die gronde is fisies- en chemies geanaliseer en toksisiteitstoetse is uitgevoer. Twee addisionele kontolegronde is ook tydens die blootstellings gebruik naamlik, OECD- en LUFA2.2-grond. Die chemiese analises van die ploegverwerkte toetsgronde het getoon dat daar steeds swaarmetale en hoë vlakke van dieselgekoppelde organiese koolwaterstowwe in die gronde teenwoordig is. Kontaminante was in hoër konsentrasies teenwoordig in die grond van die noordelike gebied as in dié van die suidelike gebied. Drie spesies van grondorganismes is gebruik tydens standaard toksisitetitstoetse. Eisenia andrei, Enchytraeus doerjesi en Folsomia candida is blootgestel aan die onderskeie toets- en kontrolegronde waarna hul oorlewing, groei, voortplantingsukses en vermydingsreaksies bestudeer is. Blootstellings aan die ploegverwerkte toetsgronde het geen akute toksisiteit vir enige van die spesies getoon nie. F. candida se juveniele produksie was laer in beide noordelike- en suidelike toetsgronde (289.42 ± 58.62 en 253.33 ± 122.94 onderskeidelik) as in die kontolegrond (479.89 ± 30.42). E. doerjesi blootstellings het ‘n toename in juveniele getalle getoon in die noordelike- en suidelike toetsgronde (339.75 ± 76.92 en 414.00 ± 17.78) in vergelyking met die ongekontamineerde kontolegrond (57 ± 34.39). Kokonproduksie by E. andrei was soorgelyk in die suidelike toetsgrond en ongekontamineerde kontrolegronde (19.00 ± 5.3 en 18.5 ± 9.7 onderskeidelik) maar beduidend minder as in noordelike toetsgrond (1.25 ± 0.7). Slegs E. doerjesi het ‘n beduidende vermydingsreaksie vir die noordelike toetsgronde getoon. Om die sensitiwiteit van die organismes aan vars API-slik te bestudeer, is hulle blootgestel aan konsentrasiereekse van API-slik in die onderskeie kontrolegronde. Die effektiewe konsentrasie (EK50) is bereken as die konsentrasie van API-slik wat die bestudeerde eindpunte met 50% sal verminder in vergelyking met die kontrolegrond Die EK50-waardes vir al die spesies het verskil na blootstelling aan die onderskeie kontrolegronde. Dus, die toksisiteit van die API-slik is tot ‘n sekere mate ook afhanklik van die fisiese grondeienskappe van die blootsellingssubstraat. Die voortplanting van F. candida was die gevoeligste eindpunt vir die blootstelling aan API-slik in kontolegrond (EK50 = 90 mg/kg) en E. doerjesi was die minste gevoelig in LUFA2.2 grond (EK50 = 36000 mg/kg). Vyf plantspesies is ook blootgestel aan API-slikgekontamineerde potgrond en die saadontkiemingssukses, vroeë groeikoers en biomassa is bestudeer. Alhoewel plante nie so sensitief was vir die API-slik soos die gronddiere nie, was blaarslaai en gras die meeste geaffekteer tydens die blootstellings. Boontjies was die ongevoeligste en met die toevoeging van lae konsentrasies API-slik (2.5% API-slik), is hul groeikoers selfs gestimuleer. Uit die studie was dit duidelik dat die suidelike deel van die grondstuk meer suksesvol as die noordelike geremidieer is en dat meeste grondorganismes wat daaraan bloot gestel is nie geaffekteer is deur die vlakke van kontaminasie wat steeds teenwoordig is in die grond nie. Die toetsgronde uit die noordelike deel het egter steeds negatiewe effekte op die grondorganismes gehad. Dit word voorgestel dat die koolwaterstof kontaminasie verder geremidieër behoort te word in die noordelike deel van die grondstuk voordat verdere ploegverwerking van die afval daar gedoen word.

L’industrie de traitement de surfaces (TS) utilise de nombreux produits chimiques, en particulier des métaux toxiques et des substances organiques, qui sont connus pour être nocifs vis-à-vis des humains et de l’environnement. En raison d’une réglementation de plus en plus stricte, les effluents contenant des métaux lourds (Zn, Cu, Ni, Fe, Al, Cr, etc.) et de la charge organique caractérisée par le paramètre DCO (demande chimique en oxygène) doivent être traités. Il existe une grande variété de procédés de traitement des eaux usées provenant de la filière traitement de surface. En général, les systèmes conventionnels dedétoxification se composent principalement d’un ajustement de pH, d’une oxydation des cyanures et d’une réduction des chromes, suivi d’une précipitation sous forme d’hydroxydes et d’une clarification, et parfois d’une étape d’adsorption sur charbonpour enlever la DCO résiduelle. Cependant, la technologie sur charbon actif présente plusieurs problèmes tels que la saturation rapide et des problèmes de colmatage et de régénération des réacteurs. Comme les résines d’échange d’ions, leur utilisation est restreinte due au coût élevé. Pour ces raisons, la plupart des petites et moyennes entreprises ne peuvent pas utiliser de tels traitements. Ainsi, afin de répondre à ces problématiques, de nombreuses études sont menées pour trouver des alternatives peu coûteuses, qui soient efficaces et acceptables pour un usage industriel. Dans cette étude, la bio-adsorption sur un bio-adsorbant d’amidon réticulé a été utilisée pour retenir les métaux et la DCO contenus dans différents effluents industriels. L’adsorption a été étudiée en fonction du temps de contact, de la masse d’adsorbant et de la charge polluante (concentration, nature). L’influence de ces paramètres sur l’efficacité d’adsorption a été évaluée en utilisant une méthode conventionnelle en mode cuvéedite méthode en batch. Les résultats ont montré que le matériau présente des capacités d’adsorption élevées vis-à-vis des ions métalliques, ce qui permet de diminuer les concentrations métalliques en dessous des valeurs réglementaires. Des résultats similaires ont été obtenus vis-à-vis de la charge organique, et ceci quelque soit le type d’effluent. Afin d’évaluer l’impact des rejets industriels provenant de quatre entreprises différentes de TS, nous avons effectué des tests écotoxicologiques normalisés basés sur l’utilisation de graines de laitue Lactuca sativa. Nous avons mesuré le taux de germination, la longueur et la masse deslaitues. Les résultats ont permis de comparer la toxicité des quatre rejets: les rejets contenant du cuivre et du nickel ont un impactbeaucoup plus élevé que ceux contenant du zinc ou de l’aluminium. De plus, les tests de germination effectués à l’aide de solutions synthétiques ont confirmé que les mélanges de métaux présentent une toxicité plus élevéeque celle de leurs constituants considérés isolément. Les testsde phytotoxicitéont été également réalisés sur les rejets industriels avant et après adsorption. Ces tests biologiques ont confirmé l’efficacité du procédépour diminuer fortement la toxicité du rejet. L’abattement chimique et la réduction de la toxicité ont démontré que la bio-adsorption sur un matériau non-conventionnel peut être une étape de finition intéressante pour la détoxification des rejets industriels.Enfin, les tests biologiques normalisés sont rapides, faciles à mettre en œuvre et parfaitement reproductibles. Ils pourraient être utilisés en routine pour évaluer les impacts d’un rejet industriel, même lorsque celui-ci satisfait aux exigences réglementaires / The surface-treatment industry consumes an important range of chemicals, in particular toxic metals and organics that are known to be harmful to humans and environnment. Because of more and more stringer regulations, effluents polluted with heavy metals and organics characterized by chemical oxigen demand must be treated.[...]

As indústrias têxteis da região de Americana geram grande quantidade de efluentes e resíduos sólidos com grande carga de corantes que são naturalmente de difícil degradação. Assim o objetivo do presente trabalho foi avaliar a possibilidade de biodegradação dos corantes têxteis RBBR, índigo e preto enxofre, e dos resíduos resultantes da Estação de Tratamento de Esgoto da cidade de Americana, SP, (DAE Americana), a qual trata 400 l s-1 de esgoto municipal junto com efluentes de 43 indústrias têxteis. Foram testados quanto à capacidade de degradação a bactéria Acinetobacter johnsonii, os fungos basidiomicetos Pleurotus sajor-caju e Pleurotus ostreatus, várias espécies de cianobactérias e também material da planta raiz-forte contendo alto teor de enzimas peroxidases. A eficiência da degradação foi avaliada em termos de descoloração através de espectrofotômetria para as amostras líquidas e refletância para as amostras sólidas, e toxicidade utilizando como bioindicadores Hydra attenuata, a alga Selenastrum capricornutum, raízes de cebola (Allium cepa) e sementes de alface (Lactuca sativa). A atividade das enzimas ligninolíticas produzidas pelos fungos basidiomicetos foi determinada e alterações celulares durante a degradação foram estudadas através de microscopia eletrônica. Foi também padronizado um teste novo para uso com amostras sólidas, atualmente utilizado para amostras líquidas, chamado Luminotox. Este teste utiliza enzimas extraídas do sistema fotossintético de plantas para estimar a toxicidade das amostras, utilizando como parâmetro a redução na fluorescência emitida por estas enzimas. Vários procedimentos foram testados para exposição das enzimas às amostras e os resultados comparados com o teste Microtox. Os organismos testados foram capazes de degradar os corantes técnicos índigo e RBBR e foram eficientes na descoloração e diminuição da toxicidade do efluente da ETE. A cianobactéria Phormidium foi capaz de degradar o corante índigo completamente e foi então testada com sucesso em Bioreator de 6 l. Os fungos Basidiomicetos e a planta raiz-forte mostraram serem capazes de descolorir o lodo da ETE, entretanto a toxicidade foi aumentada após o tratamento. / The degradation of three textile dyes (RBBR, Indigo and Sulfur Black) and also the wastewater from the Municipal Treatment Station, Americana, SP, Brazil, which treats 400 l s-1 of effluent from domestic and textiles mill, were studied. The decolorization was tested for several organisms including bacterium, white-rot fungi, cyanobacterium and horseradish roots. Detoxification was appraised with three bioassays comprising the cnidarian Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The ligninolytic enzyme activity of the whiterot fungi strains was evaluated and cellular alterations were also studied by electron microscopy. The organisms decolorized the dyes indigo, RBBR and the effluent studied, with color removal and toxicity reduction. The cyanobacterium Phormidium was able to degrade completely the indigo dye in a Bioreactor with 6 l of capacity without increase in the toxicity. The sludge was decolorized by white rot fungi and horseradish, but the toxicity increased after the treatment. However, since the organisms showed the ability to decolorize these residues, it can be used as pre-treatment resulting in a less complex composition of sludge. After that, a study for developing a protocol for analyzing sediment samples was made based in a recent toxicity test for liquid samples. This test uses enzymes extracted from tylacoids membranes of plant photosynthetic system for evaluate the toxicity, using as parameter the fluorescence emitted by the enzymes. Several procedures were tested for exposition of the enzymes to sediment and the results were compared with the Microtox test.

Fontes de poluição atmosférica têm aumentado em países em desenvolvimento, tornando extremamente difícil o acesso aos efeitos da poluição atmosférica na saúde pública. Bioensaios com plantas têm sido extensivamente utilizados para monitorar a poluição atmosférica em áreas desprovidas de sistemas de monitoramento da qualidade do ar convencionais pela sua simplicidade, baixo custo e alta sensibilidade. O presente estudo visa caracterizar a distribuição espacial da concentração de poluentes no entorno de indústrias através de evidências de toxicidade celular e acúmulo foliar utilizando planta local (Catharanthus roseus (L.) G. Don). O abortamento polínico foi quantificado em microscópio óptico (400x). O acúmulo de elementos traços foi avaliado em EDXRF (Energy Dispersive X-Ray Fluorescence). Os resultados obtidos para a área de estudo 1 mostram que a taxa de abortamento polínico é maior quanto mais próximo da indústria (p=0,047). Para o acúmulo foliar, foram encontrados os elementos S, Fe e Na que se relacionam com produtos de combustão; processo industrial; e aerossol marinho. Para a área de estudo 2, a taxa de abortamento polínico aumenta com a proximidade da área de alto tráfego veicular assim como a concentração dos elementos Al, Cu, S e Zn nas folhas pela Análise de Regressão Linear. Este estudo mostra que as áreas no entorno de fontes emissoras de poluição têm alta concentração de elementos - traço e dano celular o que indica riscos à saúde da população local. Nossos resultados reforçam que o uso de metodologias alternativas e simples como testes de abortamento polínico e bioacumulação em folhas são apropriados para caracterizar gradientes de concentração em áreas desprovidas de sistema de monitoramento da qualidade do ar, em escalas maiores do que as já estudadas. A combinação de técnicas de biomonitoramento e geoprocessamento pode ser utilizada para monitoramento ambiental em áreas com tecnologia limitada / Developing countries are experiencing increases in air pollution sources, making assessment of air pollution impact on human health extremely difficult. Plant bioassays have been widely employed to monitor air pollution in areas devoid of conventional air pollution monitoring systems because of their simplicity, low cost and high sensitivity. The aim of this study was to determine the area of influence of industries using local flora (Catharanthus roseus (L.) G. Don). Abortive pollen tests and the accumulation of toxic elements in leaves were used to detect possible risks to health of the local population. Abortive grains were evaluated through the use of a microscope under 400-fold magnification. The trace elements accumulation was evaluated by using EDXRF (Energy Dispersive X-Ray Fluorescence). Results for study site 1 shown that the closer the distance from the industry, the higher the pollen abortion rate (p=0,047). For bioaccumulation test, S, Fe and Na were associated to combustion of fossil fuels, industrial process and marine aerosol. For study site 2, the closer the distance from the major source of traffic, the higher the pollen abortion rate. The same behavior was observed for Al, Cu, S and Zn concentrations in Linear Regression Analyses. The distribution of element concentrations was elaborated in maps with the obtained results. This work showed that the areas surrounding the emission sources had a higher concentration of toxic elements, leading to greater biological damage, which indicates health risks to the local population. Our results reinforce that the use of alternative and simple methods such as pollen abortion rates and bioaccumulation in leaves are appropriate for characterizing air quality gradients in areas devoid of conventional air pollution monitoring systems, even at greater scales than have been tested before. The association of this technique and geographic information system can be used for environmental screening in areas with limited technology