Actinomycetes and fungi were successfully isolated from both New Zealand and Malaysian marine invertebrates and classified as facultatively marine based on their ability to grow on both sea water and non-sea water media. Most of the extracts obtained from selected isolates were cytotoxic. A clear preference of the actinomycetes for solid-state fermentation was observed, however, for fungi no significant preference was seen. Three isolates of Streptomyces spp., four Penicillium spp. and two Paecilomyces spp. whose extracts showed good cytotoxicity were selected for further investigation. A small-scale extract obtained from a solid culture of Streptomyces sp. (LA3L2) showed good cytotoxicity and a new cytotoxic metabolite was isolated from a large-scale extract of Streptomyces sp. (LA3L2). This metabolite was characterized as S-methyl 2,4-dihydroxy-6-isopropyl-3,5-dimethylbenzothioate (5.15) and is only the third compound reported to contain the S-methyl benzothioate group. Two known compounds, montagnetol (5.16) and erythrin (5.18), were isolated from a further large-scale cultivation of Streptomyces sp. (LA3L2) and is the first reported actinomycete to produce these lichen-related compounds. In addition, two known inactive metabolites (bohemamine (5.1) and bohemamine B (5.2)) were identified from the small-scale extract. Streptomyces sp. (LA3L2) was also investigated for the effect of temperature and salinity on growth and cytotoxicity and shown to produce bohemamine only at 20 - 28℃ and 4% sea salt concentration on solid media. This isolate gave a low yield of active metabolite under all conditions. Small-scale extracts of two other Streptomyces spp. yielded three known cytotoxic metabolites. These were thiazostatin B (7.14) from Streptomyces sp. (LA5L4) and chromomycin A2 (7.1), chromomycin A3 (7.2) and chromomycin 02-3D (7.3) from Streptomyces sp. (LA3L1). All four Penicillium spp. produced known metabolites. Penicillium sp. (LY1L5) yielded two known metabolites, cycloaspeptide A (7.4) and α-cyclopiazonic acid (7.5). α-Cyclopiazonic acid (7.5) and three other known metabolites (roquefortine A (7.6), cyclopeptin (7.7) and viridicatin (7.8)) were isolated from Penicillum sp. (KK3T23). Penicillium sp. (KK3T8) produced brefeldin A (7.10), while mycophenolic acid (7.12) and brevianamide A (7.11) were produced by Penicillium sp. (KK4T14b). The effect of salinity on growth and cytotoxicity was investigated for the two Penicillium isolates producing the cytotoxic metabolite, α-cyclopiazonic acid (7.5). Saline conditions were not required for growth but metabolite production differed between the two isolates with respect to salinity. Isolate LY1L5 required saline conditions for α-cyclopiazonic production whereas isolate KK3T23 produced the metabolite under non-saline conditions and in concentrations of sea salt up to 6%. Three known compounds, indole-3-carboxylic acid (7.15), indole-3-carboxylate (7.17) and 5-carboxymellein (7.16) were identified from Paecilomyces sp. (PR5L9). Investigation of a small-scale extract obtained from a solid culture of another Paecilomyces sp. (PR10T2) resulted in the isolation and characterization of a unique structure of a symmetrical cyclic depsipeptide, epi-angolide (NAM 6-1). NAM 6-1 was considered as a new compound based on four homoisomeric configurations (A1, A2, A3 and A4). The value of dereplication procedures with respect to the rapid identification of metabolites and enhancement of in-house metabolite libraries is discussed. Structural elucidation of nine known metabolites (7.1, 7.2, 7.3, 7.5, 7.6, 7.7, 7.8, 7.10 and 7.11) was greatly aided by the in-house dereplication techniques using LC-MS-UV and AntiMarin database. A significant advantage was gained by the use of the CapNMR which enabled NMR characterization of very small quantities of metabolites (<20 µg). Approximately <5 µg of materials were required to perform 1D proton NMR experiments for the dereplication of seven known compounds; bohemamine (5.1), bohemamine B (5.2), thiazostatin B (7.14), indole-3-carboxylate (7.17) and 5-carboxymellein (7.16). Approximately 20 µg of materials were needed to acquire 1D and 2D (HSQC, HMBC and NOE) NMR spectra for structural elucidation of the new metabolite, S-methyl 2,4-dihydroxy-6-isopropyl-3,5-dimethylbenzothioate (5.15). Some 8 µg of materials were sufficient to perform 1D and 2D (COSY, HSQC and HMBC) NMR experiments for complete structural characterization of two known metabolites, montagnetol (5.16) and erythrin (5.18). Approximately 10 µg of materials were needed to acquire 1D and 2D NMR (COSY, HSQC and HMBC) experiments for structural elucidation of the new compound, epi-angolide NAM 6-1 (A1, A2, A3 and A4). Rapid identification of known fungal metabolites enabled the in-house HPLC-UV/Rt library to be enhanced by eight metabolites (7.5, 7.6, 7.7, 7.8, 7.10, 7.11, 7.17 and 7.16). An HPLC-UV/Rt library for actinomycete metabolites was successfully established with the insertion of eight known metabolites (5.1, 5.2, 5.16, 5.18, 7.1, 7.2, 7.3 and 7.14).

Doctor of Philosophy / The problem of water scarcity has become one of the most controversial topics in Australia over the past decades, with particular focus being the ‘sustainable’ allocation of water between extractive and environmental purposes. Geographical factors are defining the extreme variability in climate and water supply in Australia and, in the past, this was used as a rationale for the construction of large irrigation projects to deliver water to rural, urban, and industrial users. During this ‘expansionary’ phase of Australia’s water use sector, the cost of augmenting supply was relatively low and environmental considerations were secondary to the development imperative. As a result, water resources became over-allocated for extractive uses spurred on by consistent underpricing of water, which indicated a failure to reflect the true cost of water supply. As Australia’s water economy entered a ‘mature’ phase, it was no longer possible to increase supply cheaply as the most easily accessible water resources had already been captured. This was followed by widespread environmental degradation manifested in the Murray- Darling Basin, the nation’s largest river basin which hosts much of Australia’s agricultural production. Consequently, the focus shifted towards demand management, leading to a myriad of regulation aimed at increasing the allocative efficiency of scarce water resources. Towards this end, substantial government funding was injected into the various initiatives throughout the water reform process. Despite the on-going government activities in the area of water reform, the understanding of the actual economic impact and environmental outcomes of various water policies in practice remains limited. In the absence of such understanding, the effectiveness of various government water initiatives is ambiguous and inevitably compromised. The present study addresses this knowledge gap by establishing a method for evaluating the economic and environmental outcomes of environmentally-oriented polices that affect irrigated industries in a catchment. The method is based on an integrated biophysical and economic modelling approach, which enables spatial relationships to be captured accurately allowing a more realistic analysis. Information generated from a computer based biophysical simulation model form the basis of an economic optimisation model with constraints pertaining to environmental targets and water supply limits. The economic model consists of a linear programming and dynamic programming component, and involves the optimisation of resource use from a catchment manager’s perspective, seeking to achieve efficient resource use but at the same time conform to given environmental objectives. This embedded linear and dynamic programming approach was required to determine the optimal intra-seasonal and inter-seasonal water allocation, given various catchment environmental targets. The interdisciplinary approach enables the economic and ecological outcomes of the catchment management policies to be simulated and assessed at a spatially explicit scale, due to the link to Geographical Information Systems (GIS) in the biophysical model. The overall objective was to create a decision-making framework that could be used to determine the least-cost means of meeting environmental targets and resource constraints. The solutions to the analysis are directly applicable to the case study, the Mooki catchment in northern New South Wales (NSW), but with an adaptable framework that can be applied to other catchments. Specific objectives include an evaluation of the possibility of using alternative irrigation systems, as well as an evaluation of the benefits that can be realised by establishing water market, in the light of environmentally-oriented catchment policies for the case study. The economic cost of achieving environmental targets pertaining to environmental flow requirements and salinity reduction, in the form of end-of-valley salinity targets, was explicitly calculated through the economic model. While salinity targets have been set for NSW catchments, the practicality of such targets is in question, given the substantial reductions in water allocation to irrigation activities, which is one of the key contributors to deep-drainage. An additional objective in this study was therefore to investigate the value of having deep drainage targets. A further consideration is the effect of “external agents” in the form of government plans to buyback entitlements from irrigation districts, or the possibility of significant water rights purchases from mining industries. The implications of external water market entrants on the regional agricultural industry were examined.

Thesis (Ph.D.)--Flinders University, School of Chemistry, Physics & Earth Sciences. / Typescript bound. Includes bibliographical references: (leaves xx) Also available online.

Thesis (M.S.)--Naval Postgraduate Schoool, 1993. / Cover title. "March 1993." Includes bibliographical references (p. 75-84).

Thesis (Ph. D.)--Université de Nantes, L'U.E.R. des Sciences de la Nature, 1979. / Accompanying map: "Carte des points de prélèvements éffectués dans l'estuaire de la Loire." Includes bibliographical references (p. 213-227).

Thesis (M. Sc. (Zoology and Entomology))--Rhodes University, 2005.

Thesis (M. Sc. (Geography))--Rhodes University, 2006.

Μέχρι σήμερα η επίδραση της αλατότητας στη διεργασία της ρόφησης των οργανικών ρύπων σε στερεούς ροφητές έχει μελετηθεί θεωρώντας ότι η ρόφηση είναι μία γραμμική διεργασία που εξαρτάται από το κλάσμα του οργανικού άνθρακα. Μελέτες της τελευταίας δεκαετίας έχουν αποδείξει ότι η ρόφηση των οργανικών στο περιβάλλον δεν είναι απαραίτητα μία γραμμική διεργασία. Για ιζήματα και εδάφη με σωματιδιακούς ανθρακούχους ρύπους, όπως είναι τα σωματίδια της αιθάλης ή των εξανθρακωμάτων, έχουν παρατηρηθεί ισόθερμες καμπύλες οργανικών ρύπων με μεγάλη έλλειψη γραμμικότητας. Προκαταρκτικές μελέτες έχουν δείξει ότι πράγματι η αλατότητα επηρεάζει τη ρόφηση ανάλογα με το μηχανισμό που παρατηρείται για κάθε είδος ροφητή. Αλλιώς επηρεάζεται η ρόφηση από την αλατότητα, όταν λαμβάνει χώρα στην επιφάνεια του ροφητή, και αλλιώς στους πόρους στο εσωτερικό του ροφητή. Η παρούσα μεταπτυχιακή εργασία περιλαμβάνει πειραματική μελέτη της ισορροπίας της ρόφησης ενός οργανικού ρύπου (του φαινανθρενίου) σε διάφορους ροφητές από το γλυκό και το θαλασσινό νερό. Οι ροφητές περιλαμβάνουν ανθρακούχα σωματίδια και ετερογενή υλικά, όπως γαιάνθρακα, λιγνίτη και θαλάσσια ιζήματα από την περιοχή του Αλιβερίου, του Λαυρίου και του Σαρωνικού κόλπου (Λουτρόπυργος) που έχουν ρυπανθεί από τα παραπάνω ανθρακούχα σωματίδια. Η αλατότητα φαίνεται να επηρεάζει σημαντικά τη ρόφηση του φαινανθρενίου σε σωματίδια λιθάνθρακα όταν τα πειράματα διεξάγονται σε σχετικά χαμηλές συγκεντρώσεις (<200 μg/L). / Until recently sorption of organic compounds onto sediments was believed to be a linear process dependent on the organic carbon fraction content. Non linear sorption and heterogeneous behavior based has been recognized the last decade. Due to salinity, various effects are observed for the different carbonaceous materials on the capacity and also on the degree of nonlinearity. Each material presents a different sorption pattern and various effects due to salinity are observed (e.g. coal sorption isotherm becomes linear in the presence of salinity whereas for lignite no significant difference is observed). In the present work, we study the sorption behavior of phenanthrene onto different sorbents in salt water. Sorbents used include carbonaceous materials, coal, lignite, and marine sediments from Aliveri, Laurio, and Saronikos gulf that are polluted with carbonaceous particles. Salinity seems to affect significantly the sorption of phenanthrene onto coal particles if the experiments are performed at concentrations lower than 200 μg/L.

Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Late Embryogenesis Abundant (LEA) genes have been irrefutably linked to the osmotic stress response since their initial discovery in maturing cotton seeds. They have since been reported from a multitude of other organism where their occurrence is often associated with general responses to abiotic stress. Many studies have been conducted using LEA genes in over expression strategies to improve abiotic stress resistance. Of the known classes of LEAs, the group 1 LEAs have been widely reported, in plants, to only occur in seeds during late stages of development. Their expression coincides with the seeds acquisition of desiccation tolerance. In this thesis we present a group 1 LEA isolated from the desiccated vegetative tissues (leaves) of the resurrection plant Xerophyta humilis. Using E.coli and Arabidopsis we attempted to use XhLEA to improve salt and water deficit stress-responses, respectively. To this end we conducted soil-drought trials on two independent transgenic Arabidopsis lines expressing XhLEA under a drought inducible-promoter and monitored their responses as compared to untransformed WT (Col-0 ) controls. Solid substrate E.coli growth assays and liquid media growth curves under both stress and unstressed conditions were conducted. We found no obvious beneficial effect through the expression of XhLEA in either of the organisms. / AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar

Made available in DSpace on 2014-06-11T19:32:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-28Bitstream added on 2014-06-13T21:05:12Z : No. of bitstreams: 1 guerra_rc_dr_rcla.pdf: 1730338 bytes, checksum: 82956154d1c3e1fd309e6b0db1ba5492 (MD5) / Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (ANP) / A atividade de recuperação do petróleo tem como característica a extração de uma parcela de água misturada ao óleo. Esta água deve ser separada do petróleo antes do processamento pelas refinarias, assim, originando um resíduo conhecido como Água de Produção. Os sistemas projetados para o tratamento deste efluente empregam diferentes métodos, visando atingir maior eficiência na separação dos contaminantes da água. Entretanto, os processos de tratamento geram subprodutos que necessitam de posterior manuseio e descarte. O presente estudo tem como objetivo avaliar o lodo produzido pela etapa de tratamento biológico da água de produção em uma estação piloto de tratamento de efluentes, instalada no Terminal Marítimo Almirante Barroso, localizado no município de São Sebastião, SP, visando a disposição final deste resíduo. Os seguintes procedimentos foram realizados para tal: classificação do resíduo de acordo com os critérios da norma técnica NBR 10.004 “Resíduos Sólidos: classificação”; avaliação da toxicidade do extrato solubilizado do lodo frente à germinação, crescimento da raiz e hipocótilo das espécies Barbarea verna Mill., Brassica. oleracea L., Cucumis. sativus L. e Eruca. sativa Mill.; avaliação da toxicidade e genotoxicidade frente ao sistema teste de Allium cepa L.; determinação da biodegradação de proporções crescentes do lodo adicionado ao solo inoculado com chorume, gerado em aterro sanitário. Os resultados indicam a classificação do lodo, de acordo com os ensaios de Lixiviação e Solubilização, como resíduo não inerte; efeito tóxico sobre a germinação de sementes nas menores concentrações de aplicação do extrato solubizado; concentração de inibição CI50 para o crescimento da raiz e hipocótilo variando entre 10,49 e 25,06% do extrato solubilizado; indução de efeitos tóxicos às células meristemáticas... / Among the oil extracted from petroleum production fields a great water volume is coproduced. This water must be eliminated prior to oil processing, the resulting wastewater is known as Produced water. Looking for greater treatment efficiency, different methods are coupled for this waste stream treatment. However, all treatment methods have its own byproducts to deal for. The present work objective is to evaluate the ultimate sludge disposal conditions from a pilot oil produced water biological treatment at Terminal Marítimo Almirante Barroso, located at São Sebastião, São Paulo State, Brazil. The following procedures wore developed in achieving this intent: NBR 10.004 waste classification procedures; germination and root/hypocotyl elongation sludge solubilization extract toxicity to Barbarea verna Mill., Brassica. oleracea L., Cucumis. sativus L. and Eruca. sativa Mill. plant species; Allium cepa L. test system toxicity and genotoxicity; sludge biodegradation at different soil application rates. Results indicate sludge waste classification as not inert; sludge solubilization extract toxic effect to seed germination at the lowest tested concentrations; root and hypocotyl elongation IC50 between 10,49 and 20,06% of sludge solubilization extract concentration; toxicity to Allium cepa meristematic cells by mitotic index reduction and cell death induction and; continuous but slow sludge biodegradation rate after microorganisms to salinity adaptation at the highest evaluated sludge application rates. These results lead to ultimate disposal need of a specific industrial landfill, with adequate environmental protection measures to harmful solubilization byproducts from this solid waste and potential toxic effects to exposed organisms.