Dissertations / Theses: 'Algal Cultures'

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Glover, Katherine Jane Anne. "Development of a microfluidic tool for understanding whole cell algal cultures." Thesis, University of Oxford, 2014. https://ora.ox.ac.uk/objects/uuid:de9eb8ef-a6fa-4dab-aebb-65dc9dc3b4eb.

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This project focuses on the development, characterisation and use of a microfluidic tool to study cells in suspension, and the motility of cells. This microfluidic tool is designed to have a low convective flow, so transport is dominated by diffusion, which allows a 2D concentration gradient to be maintained and manipulated, and cells to swim without advection. The rheology of the whole cell cultures was measured and found to shear thinning. Bubbles rising through the fluid was modelled. Despite this, it was found that bubbles rising through whole cell culture would impose a shear that correlated to the viscosity at the high shear plateau. That is bubble size did not significantly affect the apparent viscosity. The medium around bubbles of any size, from 1 mm to 100 mm, has a viscosity of 0.001 Pas. Numerical simulations are used to characterise and optimise the design and operation of the microfluidic devices. Low advection within the central chamber, with desired concentration gradients, was attainable with provided the geometry and operation were within certain limits. Recommendations regarding the geometry of the device include an inlet width to inlet neck length ratio of less than 2 and a radius of less then 400 um. The inlet velocity controlled the maximum velocity within the chamber. PDMS devices were fabricated and operated and it was found that concentration gradients could be maintained, but there were limitation regarding the syringe pump. Proof of concept is presented for visualising cells within this microfluidic device. From this thesis, it has been shown that microfluidic devices have important potential for understanding the motility of microalgae in real environments and in controlled concentration gradients, although they require careful analysis and thoughtful fabrication.

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Tillett, David McIlvain. "Lipid productivity and species competition in laboratory models of algal mass cultures." Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/10274.

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Arora, Mani. "Complexity and population regulation in unicellular algal cultures of Tetraselmis : an insight into individual and social interactions." Thesis, University of Newcastle Upon Tyne, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.576963.

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"I would put my money on one fundamental principle ... all life evolves by the differential survival of replicating entities" (Richard Dawkins) This study is aimed towards understanding the complexity in unicellular eukaryotic phytoplankton populations. For my research work I have chosen Tetraselmis (Prasinophyceae) as the test organism. Prasinophycean algae are considered as ancestors of all green algae and embryophytic land plants. Tetraselmis is a key transition organism in the phylogeny of green algae. The taxonomy and phylogeny of the genus was investigated using morphological, ultrastructural, flow cytometry and molecular cladistics analysis. Partial 18s rDNA sequences from fresh material and from gene bank were analysed. In this process a new species of Tetraselmis (T. indica) from salt pans of Goa, India has been reported. The high structural and molecular divergence observed in this species pointed towards the evolution in function, hence, T. indica was chosen as the test organism. T. indica inhabits the highly dynamic salt pan ecosystem and survives in wide fluctuations of salinity and environmental parameters. Studies at cellular level, where changes in cell physiology, biochemistry and optical properties were studied as a means of evaluating their function and response to alteration in the environment were carried out. Experiments suggested the existence of structural, physiological and metabolic differentiation in Tetraselmis as indicated by flow cytometric studies, differential absorption spectras and staining patterns. Further it was observed that an incipient differentiation exists in otherwise identical cells giving rise to a heterogenous population whose components exhibit differential survival and behaviour, which work in association for the existence of population. Investigation of the biology of a single cell and its lineage helped in deciphering the consequences and implications of heterogeneity and complexity in this unicellular eukaryote. To study how component cells of a heterogenous population achieve their own behaviour, the hierarchy of subcomponents within these component cells was explored. Studies suggested that the fate of different components is set at a very early stage of cell division and hence the division products of a single cell exhibit ultrastructural and metabolic differences. To consider the social interactions, naturally associated bacteria were inoculated with the axenic cultures of cells and the differential and marked influence of each bacterium on its growth dynamics was observed. This study highlights that interrogating the complete web of individual and social interactions is of importance in understanding the functionality and regulation of unicellular life.

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com, n_moheimani@hotmail, and Navid Reza Moheimani. "The culture of coccolithophorid algae for carbon dioxide bioremediationn." Murdoch University, 2005. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20050901.140745.

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The culture of coccolithophorid algae is an attractive option for sequestration or recycling of CO2 as they can fix carbon by photosynthesis as well as in calcium carbonate scales known as coccoliths. They also produce high amounts of lipids which have a potential application as a renewable fuel. Five species of coccolithophorids (Pleurochrysis carterae, CCMP647, Pleurochrysis sp. CCMP1211, Gephyrocapsa oceanica CS-335/2, Emiliania huxleyi CCMP371, and Emiliania huxleyi CS-369) were screened for their ability to grow at high temperature. All species grew up to 28oC except E. huxleyi CS-369. However, Pleurochrysis sp. CCMP 1211 which was found to clump and can therefore not be recommended for large-scale cultivation. The salinity tolerance of these species was also examined. Growth of P. carterae, G. oceanica, and E. huxleyi in laboratory scale closed photobioreactors (plate, carboy, airlift, and tubular photobioreactors) showed the plate photobioreactor to be the best closed cultivation system. The highest productivities were achieved by P. carterae in the plate photobioreactor and were 0.54 g.L-1.d-1, 0.12 g.L-1.d-1, 0.06 g.L-1.d-1 for total dry weight, lipid and CaCO3 respectively. The growth of P. carterae and E. huxleyi was also examined in an outdoor raceway pond. The E. huxleyi culture was easily contaminated resulting in the loss of the culture in less than three weeks, but P. carterae grew well over a period of 13 months. The overall total dry weight productivity of P. carterae was 0.19 g.L-1.d-1 with lipid and CaCO3 contents of up to 33% and 10% of dry weight respectively. There was little protozoan and bacterial contamination. Medium pH increased to pH 11 during the day and was found to be a reliable variable for maintaining the health of the culture. A maximum pH achieved during the day of less than pH 8.5 indicated the imminent collapse of the culture. Heavy rain and low temperature were the main reasons for culture loss in mid winter, whereas high temperature during summer favoured P. carterae growth. A comparison of the growth of P. carterae and Dunaliella salina MUR8 in the raceway ponds showed no significant differences between these two species with regard to areal total dry weight productivity and lipid content. The effects of several limiting factors were also examined. A reduction in medium pH resulting from CO2 addition inhibited the growth of E. huxleyi in the plate photobioreactor, whereas P. carterae growth and productivities increased in the pH range of pH 7.7 to 8.0 in the plate photobioreactor and pH 9.1 to 9.6 in the outdoor raceway pond. The best operational pond depth for outdoor raceway culture of P. carterae was between 16 cm and 21 cm. Early morning temperatures, especially during the winter, highly affected the growth of P. carterae in the raceway pond, whereas artificially increasing the medium temperature improved the health of the culture but resulted in little increase in productivity. Photosynthesis of P. carterae was found to be highly inhibited by high oxygen concentration in the medium irrespective of temperature or irradiance. An economic model of P. carterae in a 63 ha raceway plant resulted in a cost for the biomass of between 7.35 Aus$.Kg-1 and 14.17 Aus$.Kg-1 depending on the harvesting method used.

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Sólorzano, Cháves Eddyn Gabriel. "Avaliação de cultivos de Kappaphycus alvarezii em diferentes condições climáticas e hidrólise enzimática do resíduo gerado pós-processamento de Carragena /." Araraquara, 2017. http://hdl.handle.net/11449/152614.

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Orientador: Fernando Masarin
Banca: Banca: Kelly Johana Dussan Medina
Banca: Samuel Conceição de Oliveira
Resumo: Kappaphycus alvarezii é uma macroalga vermelha utilizada principalmente para produção industrial de hidrocolóides (principalmente carragena). O cultivo de K. alvarezii foi estabelecido como uma atividade econômica importante em mais de 20 países. Os principais componentes da biomassa de K. alvarezii são carboidratos. O processamento de carragena a partir de K. alvarezii promove a formação de um resíduo rico em glucana. Objetivo: Avaliar o desenvolvimento de cultivos de K. alvarezii em diferentes condições climáticas e averiguar o efeito da hidrólise enzimática sobre os resíduos obtidos pós-processamento de carragena. Métodos: A parte experimental envolveu o cultivo de 4 cepas de K. alvarezii ao longo de um ano no oceano atlântico em Ubatuba-SP. A partir dos dados dos cultivos foram calculadas as velocidades de crescimento e produtividades. Cultivos selecionados com base nos dados de produtividade foram previamente misturados e homogeneizados e submetidos a um pré-tratamento com KOH 6%. As biomassas previamente pré-tratadas com KOH 6% foram extraídas com água para a obtenção das carragenas e dos resíduos. As frações obtidas no processamento foram caracterizadas quimicamente. Os resíduos foram hidrolisados enzimaticamente com celulases comerciais. Resultados: Foram diferenciados três níveis de produtividade (A, setembro-dezembro de 2013; B, janeiro-março de 2014; C, abril-junho 2014). Os valores de produtividade foram maiores no nível B e intermediários nos níveis A e C. Os val... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The fungus of genus Paracoccidioides is the etiological agent of paracoccidioidomycosis (PCM), an important mycosis in Brazil and Latin America. There are different available therapies, as antifungals belong to the class of polyenes, azoles and sulfonamides. The development of new antifungal agents with greater effectiveness is required to prevent relapse and reduce side effects, the period of treatment and sequelae. The gallic acid molecule with different modifications (alkyl gallates) showed antifungal activity against a representative panel of pathogenic fungi. The decyl gallate (G14) was the study object of this work, for which the Paracoccidioides-host interaction was connected with the mechanism of action. Therefore, the fungus Paracoccidioides lutzii (Pl01) was challenged with the G14 to analyze the changes in the development of budding and cell viability by MTT assay. Then, it was assessed the influence of the G14 in the interaction rate of Pl01 with murine alveolar macrophage lineage AMJ2-C11, with mammalian lung lineage A549 and MRC-5, and hemocytes of Galleria mellonella larvae using assays by flow cytometry. The compound G14 was evaluated for survival rate of infected G. mellonella larvae and to capacity of modulation of nitric oxide production in RAW macrophages. The mechanism of action was performed by chemical-genetic interaction assay followed by genetic interaction, which involves comparing a mutant collection, of Saccharomyces cerevisiae yeast, with hypersensitive profile to G14 to double mutant database to predict via affected. In P. lutzii (Pl01)... (Complete abstract click electronic access below)
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Johnson, Michael Ben. "Microalgal Biodiesel Production through a Novel Attached Culture System and Conversion Parameters." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/32034.

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Due to a number of factors, the biodiesel industry in the United States is surging in growth. Traditionally, oil seed crops such as soybean are used as the feedstock to create biodiesel. However, the crop production can no longer safely keep up with the demand for the growing biodiesel industry. Using algae as a feedstock has been considered for a number of years, but it has always had limitations. These limitations were mainly due to the production methods used to grow and harvest the algae, rather than the reaction methods of creating the biodiesel, which are the same as when using traditional crops. Algae is a promising alternative to other crops for a number of reasons: it can be grown on non arable land, is not a food crop, and produces much more oil than other crops. In this project, we propose a novel attached growth method to produce the algae while recycling dairy farm wastewater using the microalga Chlorella sp. The first part of the study provided a feasibility study as the attachment of the alga onto the supporting substrate as well as determining the pretreatment options necessary for the alga to grow on wastewater. The results showed that wastewater filtered through cheesecloth to remove large particles was feasible for production of Chlorella sp, with pure wastewater producing the highest biomass yield. Most importantly, the attached culture system largely exceeded suspended culture systems as a potentially feasible and practical method to produce microalgae. The algae grew quickly and were able to produce more than 3.2 g/m2-day with lipid contents of about 9% dry weight, while treating dairy farm wastewater and removing upwards of 90% of the total phosphorus and 79% of the nitrogen contained within the wastewater. Once the â proof-of-conceptâ work was completed, we investigated the effects of repeat harvests and intervals on the biomass and lipid production of the microalgae. The alga, once established, was harvested every 6, 10, or 15 days, with the remaining algae on the substrate material functioning as inoculums for repeated growth. Using this method, a single alga colony produced biomass and lipids for well over six months time in a laboratory setting. The second part of this study investigated another aspect of biodiesel production from algae. Rather than focus solely on biomass production, we looked into biodiesel creation methods as well. Biodiesel is created through a chemical reaction known as transesterification, alcoholysis, or commonly, methylation, when methanol is the alcohol used. There are several different transesterification methods. By simplifying the reaction conditions and examining the effects in terms of maximum fatty acid methyl esters (FAME) produced, we were able to determine that a direct transesterification with chloroform solvent was more effective than the traditional extraction-transesterification method first popularized by Bligh & Dyer in 1959 and widely used. This synergistic research helps to create a more complete picture of where algal biodiesel research and development is going in the future.
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Park, Sichoon. "The selective use of chlorine to inhibit algal predators and avoid pond crashes for the algae-biodiesel industry." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51867.

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As algae-derived biofuel is a promising renewable energy source, it is well-established that micro-algae have the potential to make a significant contribution to transportation fuel demand. Although it has many advantages including high areal productivity, there are many negative factors. One of these factors is the predation of algae by amoebas, protozoans, ciliates and rotifers, particularly in open pond systems. For example, the rotifer Brachionus plicatilis, is able to eat as much as 12,000 algae cells per hour and can be responsible for an entire pond crash within days. Thus, these higher organisms need to be controlled in order to satisfy large-scale algae crop and biofuel production demand. One method of predation control involves the introduction of a toxic chemical to an algal culture that the predator has a higher sensitivity to with respect to algae. Ideally, predation could be minimized or eliminated without a substantial effect on the algal culture growth. Chlorella kessleri was used as the algal culture and Brachionus calyciflorus as the source of predation. Research was conducted in five stages. First, chlorine dissipation tests were carried out using spring water, distilled water, Bolds Basal Medium (BBM), and three different dry weights of algal suspension in order to analyze the dissipation rate of the residual chlorine. The results showed that chlorine in distilled water and spring water rarely dissipated while chlorine concentration in algal suspension rapidly decreased by a maximum of 90% within the second hour. Second, acute chlorine toxicity tests were conducted in order to find the 24-hr LC50 of B. calyciflorus. The 24-hr LC50 of the test animal was 0.198 mg Cl/L. Third, chlorine toxicity tests were conducted in order to find the LC50 of Chlorella kessleri. The 24-hr LC50 of C. kessleri was 0.321 mg Cl/L. Based on these results, the test animal was more sensitive to chlorine than the test algae; therefore chlorine may be used to avoid algae pond crashes by B. calyciflorus. Fourth, C. kessleri and B. calyciflorus were combined into one test to determine how long it would take to observe an algal culture crash. The result demonstrated that the higher the population of predators in algal suspension, the faster it crashed. Finally, chlorine, C. kessleri, and B. calyciflorus were combined into one test to determine what chlorine concentration and dosing interval was needed to significantly reduce predation without significantly reducing algae growth. The results of the fifth experiment showed that the effective intermittent chlorine concentration was between 0.45 and 0.60 mg Cl/L, and a short interval of chlorine dosing was effective in inhibiting rotifers in algal suspension. Even though the rotifers in algal suspension were inhibited by 0.45 to 0.60 mg Cl/L, algae growth was greatly inhibited by chlorine. In this respect, future work is needed to reduce the effect on algae by chlorine or alternative chemicals.

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Florêncio, Taise. "Uso de plantas aquáticas como meio de cultura no cultivo de Ankistrodesmus gracilis (Reinsch) Korshikov (Chlorophyceae) /." Jaboticabal, 2017. http://hdl.handle.net/11449/151108.

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Orientador: Lúcia Helena Sipaúba-Tavares
Banca: Maria Stela Mioli Catilho Noll
Banca: Cintia Erbert
Resumo: A biotecnologia utilizada no cultivo de microalgas à base de meio comercial é de alto custo. Sendo assim, alguns estudos indicam que o uso de meios de cultura alternativos com a finalidade de reduzir o preço de produção em curto espaço de tempo e mantendo alto valor nutricional, são procedimentos a serem adotados. O objetivo deste trabalho foi avaliar a qualidade de diferentes meios de cultivo a base de macrófitas. O meio com macrófita foi associado ao fertilizante inorgânico NPK (20:5:20). O experimento foi conduzido no período de 28 dias em triplicata. O meio de cultura com E. crassipes alcançou maior densidade celular (434 x 105 cel. mL-1), comparado com os outros meios de cultura com macrófitas que variaram de 319,7 x 105 cel. mL-1 (E. azurea) a 223,5 x 105 cel. mL-1 (T. domingensis). Durante o período experimental o oxigênio dissolvido, pH e condutividade elétrica não apresentaram diferenças significativas (P>0,05). A taxa de crescimento e densidade celular da microalga cultivada em meio de cultura com plantas aquáticas foram maiores (P>0,05) do que no meio NPK porém, similares (P<0,05) ao meio comercial CHU12. Em relação aos nutrientes, o teor de N (67 g.L-1) foi o mais elevado no meio de cultura com T. domingensis e os demais nutrientes (P, K, Ca, S, B, Cu, Fe e Zn) apresentaram concentrações abaixo de 35 g.L-1, nos diferentes meios utilizados. O uso de macrófitas como fonte alternativa para ser utilizada como meio de cultura no desenvolvimento de A. gracilis demonstro... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Since biotechnology in commercial medium-based culture of microalgae has very high costs, several studies recommend alternative medium cultures to reduce product costs in a short time period, coupled to high nutritional values. Objective of this work was to evaluate the quality of different macrophytes based culture media. Medium with macrophyte was associated with inorganic fertilizer NPK (20:5:20). Assay was conducted for 28 days, in triplicate. Culture medium with E. crassipes had the greatest cell density (434 x 105 cel. mL-1) when compared to other culture media with macrophytes and ranged between 319.7 x 105 cel. mL-1 (E. azurea) and 223.5 x 105 cel. mL-1 (T. domingensis). Dissolved oxygen, pH and electric conductivity did not show any significant differences during the experimental period (p>0.05). Growth rate and cell density of microalga cultivated in a medium with aquatic plants were greater (p>0.05) than in NPK medium, albeit similar (p<0.05) to the commercial medium CHU12. Further, N rate (67 g.L-1) was the highest in culture medium with T. domingensis, whilst the other nutrients (P, K, Ca, S, B, Cu, Fe and Zn) had lower than 35 g.L-1 concentrations in the different media employed. The use of macrophytes as an alternative source as culture medium in the development of A. gracilis proved to be viable from the economic and nutritional point of view, coupled to high algal biomass. E. crassipes, E. azurea and T. domingensis provided the best results.
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Fioresi, Tatiana Betioli [UNESP]. "Uso de meio a base de esterco suíno no cultivo de Ankistrodesmus gracilis (Chlorophyta) em laboratório." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/94897.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Um dos fatores importantes na criacao de larvas de peixes e o uso de alimento natural, tal como o fitoplancton, o qual pode ser cultivado em instalacoes especiais, a baixo custo com alto valor nutricional e elevada taxa de crescimento. Muitos fatores afetam o cultivo de algas como luz, nutrientes, temperatura e pH, sendo esses fatores complexos e dificeis de serem analisados separadamente, principalmente, as interacoes entre incidencia de luz e limitacao de nutrientes. Entretanto, a restricao a luz e mais impactante do que a limitacao de nutrientes, desde que a luz afeta diretamente a utilizacao dos compostos disponiveis no meio de cultura. Estudos tem sido enfatizados focalizando o cultivo de algas para a producao de alimento, utilizando-se meios alternativos como forma de baratear o custo de producao. O objetivo do presente trabalho foi avaliar e comparar o efeito do esterco suino no desenvolvimento de Ankistrodesmus gracilis, cultivada em laboratorio em dois meios: com esterco gin natura e esterco biodigerido. O experimento foi realizado no periodo de 22 dias nos volumes, de 2L e 250L, analisando a biologia, valor nutricional e a qualidade da agua do meio de cultura. Biovolume, teor de cinzas, comprimento total e concentracao de lipideos foram significativos (p<0,05) entre os volumes cultivados. O teor de proteina nao foi significativo (p>0,05) somente no meio com esterco biodigerido. As maiores densidades de A. gracilis foram observadas no volume de 2L, tendo a amostra cultivada em meio com esterco biodigerido ao longo do experimento maior densidade, com o pico ao redor do 5o dia, 6,2 x 107 celulas.ml-1. Ortofosfato, pH, alcalinidade, oxigenio dissolvido e temperatura da agua nao foram significativos (p>0,05) entre volumes e o nitrito nao foi detectado...
One of the most important factors in successfully fish rearing is probably the use of natural feed, such as phytoplankton, which may be grown in specially designed installations. So that high nutritional algae could be produced at low cost it is important to reach light production of algae and high growing rate. Many factors affect algae culture growth such as light, nutrients, temperature and pH since they directly involve algae density interactions between light incidence and limitation of nutrients are very complex and the effect of factor can not be analyzed separately. However, light restriction caused more impact than limiting of nutrients, since energy affected directly the utilization of the compounds available in the medium. Several studies focus on the culture of algae for food production through alternative methods to lower production costs. The effect of swine manure fertilization in the development of Ankistrodesmus gracilis was mensured on two medium: in natura and biodigested, during 22 days, in two volumes, 2L and 250L. The biology, nutritional value and water quality of culture medium were analyzed. Biovolume, ash rate, total length and lipids were higher (p<0.05) between treatments. Protein rate was different (p>0.05) only in the biodigested treatment. Highest A. gracilis densities were reported in 2L throughout the experiment the biodigested treatment had the highest density, 6.2 x 107 cells.ml-1, on the 5th day. Orthophosphate, pH, alkalinity, dissolved oxygen and water temperature were only different (p<0.05) between volumes. Nitrite, however, was not reported in the 2L volume treatment. Significant differences (p<0.05) between media were only reported for DBO5. Light demand was also... (Complete abstract, click electronic access below)

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Fioresi, Tatiana Betioli. "Uso de meio a base de esterco suíno no cultivo de Ankistrodesmus gracilis (Chlorophyta) em laboratório /." Jaboticabal : [s.n.], 2007. http://hdl.handle.net/11449/94897.

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Orientador: Lúcia Helena Sipaúba-Tavares
Banca: Luiz Augusto do Amaral
Banca: Márcia Noélia Eler
Resumo: Um dos fatores importantes na criacao de larvas de peixes e o uso de alimento natural, tal como o fitoplancton, o qual pode ser cultivado em instalacoes especiais, a baixo custo com alto valor nutricional e elevada taxa de crescimento. Muitos fatores afetam o cultivo de algas como luz, nutrientes, temperatura e pH, sendo esses fatores complexos e dificeis de serem analisados separadamente, principalmente, as interacoes entre incidencia de luz e limitacao de nutrientes. Entretanto, a restricao a luz e mais impactante do que a limitacao de nutrientes, desde que a luz afeta diretamente a utilizacao dos compostos disponiveis no meio de cultura. Estudos tem sido enfatizados focalizando o cultivo de algas para a producao de alimento, utilizando-se meios alternativos como forma de baratear o custo de producao. O objetivo do presente trabalho foi avaliar e comparar o efeito do esterco suino no desenvolvimento de Ankistrodesmus gracilis, cultivada em laboratorio em dois meios: com esterco gin natura e esterco biodigerido. O experimento foi realizado no periodo de 22 dias nos volumes, de 2L e 250L, analisando a biologia, valor nutricional e a qualidade da agua do meio de cultura. Biovolume, teor de cinzas, comprimento total e concentracao de lipideos foram significativos (p<0,05) entre os volumes cultivados. O teor de proteina nao foi significativo (p>0,05) somente no meio com esterco biodigerido. As maiores densidades de A. gracilis foram observadas no volume de 2L, tendo a amostra cultivada em meio com esterco biodigerido ao longo do experimento maior densidade, com o pico ao redor do 5o dia, 6,2 x 107 celulas.ml-1. Ortofosfato, pH, alcalinidade, oxigenio dissolvido e temperatura da agua nao foram significativos (p>0,05) entre volumes e o nitrito nao foi detectado... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: One of the most important factors in successfully fish rearing is probably the use of natural feed, such as phytoplankton, which may be grown in specially designed installations. So that high nutritional algae could be produced at low cost it is important to reach light production of algae and high growing rate. Many factors affect algae culture growth such as light, nutrients, temperature and pH since they directly involve algae density interactions between light incidence and limitation of nutrients are very complex and the effect of factor can not be analyzed separately. However, light restriction caused more impact than limiting of nutrients, since energy affected directly the utilization of the compounds available in the medium. Several studies focus on the culture of algae for food production through alternative methods to lower production costs. The effect of swine manure fertilization in the development of Ankistrodesmus gracilis was mensured on two medium: in natura and biodigested, during 22 days, in two volumes, 2L and 250L. The biology, nutritional value and water quality of culture medium were analyzed. Biovolume, ash rate, total length and lipids were higher (p<0.05) between treatments. Protein rate was different (p>0.05) only in the biodigested treatment. Highest A. gracilis densities were reported in 2L throughout the experiment the biodigested treatment had the highest density, 6.2 x 107 cells.ml-1, on the 5th day. Orthophosphate, pH, alkalinity, dissolved oxygen and water temperature were only different (p<0.05) between volumes. Nitrite, however, was not reported in the 2L volume treatment. Significant differences (p<0.05) between media were only reported for DBO5. Light demand was also... (Complete abstract, click electronic access below)
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Segali, Alexandra Maria Donadon Lusser [UNESP]. "Desempenho de Ankistrodesmus gracilis (Reischi) Korsikov (Chlorophyta) cultivada em três meios de cultura em laboratório." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/116024.

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A microalga A. gracilis é conhecida pela sua capacidade de ser usada em nutrição de organismos aquáticos. Alguns estudos relatam que a adição de vitamina junto ao meio de cultura promove uma melhora nas condições do cultivo. O objetivo deste estudo foi avaliar o desempenho da microalga Chlorophyceae, Ankistrodesmus gracilis, em condições controladas em três diferentes meios de cultura, sendo um comercial (CHU12) e dois alternativos (NPK (20:5:20) e Macrófita + NPK) durante o período de 28 dias de cultivo para cada meio. O experimento foi realizado em recipientes de 13L durante 28 dias, com luminosidade constante de 60 ?mol m-2 s-1 e para cada recipiente foram adicionados 20 mg de vitamina do complexo B. No meio CHU12 apresentou densidade celular máxima de 25,6 x 105 cel mL-1 e nos meios NPK e M+NPK foi de 25,5 e 24,2 x 105 cel mL-1 , respectivamente. As quantidades de lipídios obtidas no presente estudo foram, para o meio NPK o valor médio foi de 12,68% do peso seco e para os meios M + NPK e CHU12 os valores obtidos foram 9,85 e 2,82% do peso seco respectivamente. Em relação às proteínas a microalga A. gracilis apresentou valores significativos comprovando assim o seu grande potencial como nutriente na alimentação de organismos aquáticos, foram obtidos para o meio NPK valores de 41,26% do peso seco, e para os meios M + NPK e CHU12 valores de 37,71 e 31,76% do peso seco respectivamente. Através dos dados obtidos neste estudo, pode-se concluir que a utilização dos meios de cultura alternativos NPK (20:5:20) e macrófita + NPK apresentaram resultados satisfatórios no crescimento e desenvolvimento da microalga A. gracilis. Em relação à nutrição de organismos aquáticos pode ser uma grande ferramenta como alimento natural
The microalgae A. gracilis is known for its ability to be used in nutrition of aquatic organisms. Some studies report that the addition of vitamin on the culture medium promotes an improvement in the conditions of cultivation. The objective of this study was to evaluate the performance of microalgae Chlorophyceae, Ankistrodesmus gracilis, under controlled conditions in three different culture media, being a commercial (CHU12) and two alternatives (NPK (20:5:20) and Macrophyte+NPK) during the period of 28 days of cultivation for each half. The experiment was accomplished in 13L containers during 28 days, with constant brightness of 60 ?mol m-2 s-1 and for each container were added 20 mg of vitamin B complex. In the middle CHU12 has maximum cell density 25,6 x 105 cel mL-1 and NPK and M+NPK media was 25,5 and 24,2 x 105 cel mL-1, respectively. The quantities of lipid obtained in this study were, in the middle the average value was NPK 12,68% of the dry weight and the means M + NPK and the values obtained CHU12 were 9,85 and 2,82% of the dry weight respectively. In relation to protein microalgae A. gracilis presented significant values proving so its great potential as a nutrient in the feeding of aquatic organisms, were obtained for the NPK values of 41,26% of dry weight, and for the means CHU12 37,71 values and M+NPK and 31,76% of the dry weight respectively. Through the data obtained in this study, it can be concluded that the use of alternative culture media NPK (20:5:20) and macrophyte + NPK presented satisfactory results in the growth and development of microalgae A. gracilis. In relation to the nutrition of aquatic organisms can be a great tool as health food

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Segali, Alexandra Maria Donadon Lusser. "Desempenho de Ankistrodesmus gracilis (Reischi) Korsikov (Chlorophyta) cultivada em três meios de cultura em laboratório /." Jaboticabal, 2014. http://hdl.handle.net/11449/116024.

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Orientador: Lucia Helena Sipaúba Tavares
Banca: Maria Stela Maioli Castilho Nol
Banca: Claudinei da Cruz
Resumo: A microalga A. gracilis é conhecida pela sua capacidade de ser usada em nutrição de organismos aquáticos. Alguns estudos relatam que a adição de vitamina junto ao meio de cultura promove uma melhora nas condições do cultivo. O objetivo deste estudo foi avaliar o desempenho da microalga Chlorophyceae, Ankistrodesmus gracilis, em condições controladas em três diferentes meios de cultura, sendo um comercial (CHU12) e dois alternativos (NPK (20:5:20) e Macrófita + NPK) durante o período de 28 dias de cultivo para cada meio. O experimento foi realizado em recipientes de 13L durante 28 dias, com luminosidade constante de 60 μmol m-2 s-1 e para cada recipiente foram adicionados 20 mg de vitamina do complexo B. No meio CHU12 apresentou densidade celular máxima de 25,6 x 105 cel mL-1 e nos meios NPK e M+NPK foi de 25,5 e 24,2 x 105 cel mL-1 , respectivamente. As quantidades de lipídios obtidas no presente estudo foram, para o meio NPK o valor médio foi de 12,68% do peso seco e para os meios M + NPK e CHU12 os valores obtidos foram 9,85 e 2,82% do peso seco respectivamente. Em relação às proteínas a microalga A. gracilis apresentou valores significativos comprovando assim o seu grande potencial como nutriente na alimentação de organismos aquáticos, foram obtidos para o meio NPK valores de 41,26% do peso seco, e para os meios M + NPK e CHU12 valores de 37,71 e 31,76% do peso seco respectivamente. Através dos dados obtidos neste estudo, pode-se concluir que a utilização dos meios de cultura alternativos NPK (20:5:20) e macrófita + NPK apresentaram resultados satisfatórios no crescimento e desenvolvimento da microalga A. gracilis. Em relação à nutrição de organismos aquáticos pode ser uma grande ferramenta como alimento natural
Abstract: The microalgae A. gracilis is known for its ability to be used in nutrition of aquatic organisms. Some studies report that the addition of vitamin on the culture medium promotes an improvement in the conditions of cultivation. The objective of this study was to evaluate the performance of microalgae Chlorophyceae, Ankistrodesmus gracilis, under controlled conditions in three different culture media, being a commercial (CHU12) and two alternatives (NPK (20:5:20) and Macrophyte+NPK) during the period of 28 days of cultivation for each half. The experiment was accomplished in 13L containers during 28 days, with constant brightness of 60 μmol m-2 s-1 and for each container were added 20 mg of vitamin B complex. In the middle CHU12 has maximum cell density 25,6 x 105 cel mL-1 and NPK and M+NPK media was 25,5 and 24,2 x 105 cel mL-1, respectively. The quantities of lipid obtained in this study were, in the middle the average value was NPK 12,68% of the dry weight and the means M + NPK and the values obtained CHU12 were 9,85 and 2,82% of the dry weight respectively. In relation to protein microalgae A. gracilis presented significant values proving so its great potential as a nutrient in the feeding of aquatic organisms, were obtained for the NPK values of 41,26% of dry weight, and for the means CHU12 37,71 values and M+NPK and 31,76% of the dry weight respectively. Through the data obtained in this study, it can be concluded that the use of alternative culture media NPK (20:5:20) and macrophyte + NPK presented satisfactory results in the growth and development of microalgae A. gracilis. In relation to the nutrition of aquatic organisms can be a great tool as health food
Mestre

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Rose, P. D. (Peter Dale). "Algal biotechnology and the beneficiation of saline effluent wastes." Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1015967.

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Saline deterioration in the South African public water system has been documented and disposal of brine wastes has been identified as part of the problem. The broad aim of this research programme was to undertake an initial technical study to evaluate the feasibility of integrating algal biotechnology into a disposal function for these wastes. A demonstration of utility in the form of products and waste treatment could produce a beneficiation of saline effluents and provide incentives necessary to deal with the disposal issue. The study attempted to demonstrate a synthesis between the two main thrusts in algal biotechnology that have produced large-scale practical applications - stable, predictable algal production in saline media and the cost effective High Rate Oxidation Ponding (HROP) process for incorporating algal production into a waste treatment function. Tannery organic saline effluents and the biotechnology of Dunaliella salina culture producing β- carotene were chosen as paradigms for the study. 1. The alga was shown to grow in certain tannery effluents producing enhanced biomass yields compared to defined inorganic medium cultivation. The potential for amino acid or protein supplementation of defmed culture media was noted. 2. A reduction in organic load simultaneous with the growth of D.salina was recorded in laboratory-scale simulations of the HROP process. Rates similar to the fresh water HROP equivalent were demonstrated. 3. These results suggested the uptake and storage of organic nitrogen by D.salina. The consequent inhibition of β-carotene accumulation by the organism presented a potentially insurmountable obstacle to the feasibility of β-carotene production in this medium. Uptake and release of organic compounds, previously demonstrated in phytoplankton and other micro-algae, was confirmed in this study for D.salina. The evidence acquired indicated the internalization of both glycine and bovine serum albumin. An ultrastructural study demonstrated mechanisms by which this process might occur. 4. The release of substantial quantities of glycerol was shown. A mechanism whereby D. salina may use this to regulate ammonia availability via control of its associated bacterial population was observed. Glycerol release was identified as presenting an application in treating refractory organic wastes, such as secondary sewage sludges, by elevating C:N ratios. This could demonstrate a significant utility for brine waste impoundments. 5. A multistage production process was proposed to deal with the problem of β-carotene inhibition by separation of the growth and metabolite accumulation functions into separate unit operations. It was shown in this study that the stress of nitrogen deficiency combined with high salinity provides for effectiveβ-carotene accumulation under the conditions of low illumination that pertain in dense cultures. Subjected to these conditions effluent-grown cells show delayed but unimpaired {j-carotene accumulation. 6. A role for the plant hormone abscisic acid in mediating the stress response was demonstrated in D.salina. Fluorescence induction studies suggested the presence of a signalling process forming part of a sensitivity control mechanism. Stress induction of β-carotene accumulation could occur through four clearly defined stages. Potential was identified for using this response as a physiological probe for monitoring and regulating the stress induction process. 7. The multistage processing concept requires effective algal cell separation technology. The use of cross-flow ultrafiltration and diafiltration with a polyethersulfone tubular membrane system was demonstrated as an effective process for the recovery and washing of D. salina. Cell concentrates were produced in a viable form. 8. Process designs incorporating the findings of the research programme are presented demonstrating how effluent and organic waste treatment functions may be combined with the production of D.salina and its products. Application of the multi-stage processing concept to β-carotene production in a defined medium process was identified as offering a potential four-fold yield enhancement. This could have a significant impact on a high cost, marginal algal biotechnology process. Aspects of novelty have been claimed in provisional patents applications. A provisional demonstration of the feasibility of D.salina production in tannery effluent indicates that algal biotechnology may provide a utility for, and hence the beneficiation of saline effluent wastes.

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Berthold, Erwin David. "Enhancing Algal Biomass and Lipid Production through Bacterial and Fungal Co-Culture." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2563.

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This thesis investigates the effects of co-culturing microorganisms including 37 yeast, 38 bacteria, nine diazotrophic cyanobacteria, and three fungi on biomass and lipid production in fresh- and saltwater algae. Algal lipid content was measured using Nile Red method and gravimetric techniques. Among the algal strains tested, freshwater Coelastrum sp. 46-4, and saltwater Cricosphaera sp. 146-2-9, showed enhanced biomass yield and lipid content in response to co-culture with bacteria, cyanobacteria, and fungi. While co-culture with yeast caused inhibition of algal productivity, no difference in algal productivity was observed between nitrogen-free diazotrophic cyanobacterial co-culture and nitrogen-replete monoalgal culture. Results indicated that extracellular compounds from the freshwater bacteria Pseudomonas stutzeri and marine fungus Fusarium sp. significantly account for stimulation of lipid accumulation within algal cells, while co-cultivation with live microorganism cells stimulated biomass production in algae.

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Zitta, Carmen Simioni. "Determinação da ploidia de três linhagens de Kappaphycus alvarezii (Rhodophyta, Gigartinales) cultivadas em laboratório e análise da ontogênese de calos da linhagem tetrasporofítica marrom." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/94778.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Biologia Vegetal, Florianópolis, 2011
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Kappaphycus alvarezii (Doty) Doty ex P. C. Silva é uma alga vermelha de grande importância comercial por ser fonte de carragenana, hidrocolóide utilizado como agente espessante e gelificante em diversos ramos da indústria. Conseqüentemente, uma expansão dos cultivos por diversos países tem ocorrido durante mais de 40 anos, sendo que ao longo desse tempo, a espécie foi cultivada através de propagação vegetativa, resultando em diminuição da sua variabilidade genética. Uma das alternativas para melhorar a qualidade das linhagens cultivadas é ampliar os estudos básicos referentes à sua micropropagação e identificação da ploidia. Esse trabalho teve como objetivos: 1. determinar a ploidia de três linhagens de K. alvarezii cultivadas em laboratório; 2. analisar a ontogênese de calos da linhagem tetrasporofítica marrom. Para o primeiro objetivo, núcleos marcados com DAPI de três linhagens indicadas como "tetrasporofítica" marrom, "gametofitica" marrom e linhagem "EP" foram analisados através da microscopia de fluorescência confocal e programa ImageJ. O "tetrasporófito" marrom apresentou maior intensidade de fluorescência do núcleo, indicando o caráter tetrasporofítico (2N) quando comparado com o "gametófito" marrom e linhagem "EP", que apresentaram, respectivamente, 55,78% e 57,10% da intensidade de fluorescência, confirmando o caráter gametofítico (N) das mesmas.. Foi possível constatar ainda que esta técnica pode ser utilizada como uma ferramenta rápida para auxiliar na identificação da ploidia de linhagens até então desconhecidas. Para o segundo objetivo, explantes axênicos da linhagem tetrasporofítica marrom de K. alvarezii foram incubados em meio sólido por 60 dias. Ao 7o, 14o, 21o, 28o, 35o e 60o dia, amostras de explantes foram retirados da cultura e analisados através da microscopia de luz e eletrônica de transmissão. No final do período experimental, amostras de 60 dias foram analisadas ainda através da microscopia confocal. A formação do calo filamentoso foi iniciada na primeira semana, a partir das células corticais e medulares da região seccionada do explante em contato com o ar. Alterações na porção superior, das células corticais e medulares do explante, como o espessamento de parede celular, proliferação de membranas convolutas, aumento no número de mitocôndrias e alterações nos cloroplastos, indicaram a desdiferenciação destas células como pré-requisito para formação de células indiferenciadas. Durante todo o período experimental, as células do calo filamentoso apresentaram parede celular espessada com presença de polissacarídeos ácidos, sugerindo grande quantidade de carragenana, juntamente com polissacarídeos neutros (celulose). O citoplasma das células do filamento apresentou como principais características: grande quantidade de grãos de amido como material de reserva; presença de cloroplastos alterados com inúmeros plastoglóbulos em seu interior e tilacóides desorganizados; presença de diversas membranas convolutas e formação de vesículas vacuolares visualizadas pela compartimentalização citoplasmática. À medida que iam se proliferando os filamentos mantinham sua organização unisseriada, e ramificavam irregularmente, com diversas conexões intercelulares entre si. No interior de suas células, estruturas autofluorescentes foram observadas, sugerindo a presença de pigmentos fotossintetizantes, como também vários núcleos, indicando a capacidade de proliferação destas células. Observamos que apesar do estresse inicial causado no momento de isolamento de explantes e ínicio da cultura dos calos, os filamentos foram capazes de crescer e se desenvolver, mantendo suas células desdiferenciadas com intensa atividade metabólica. Esse conhecimento é de fundamental importância para o entendimento do processo de formação da estrutura do calo e pode criar bases para a compreensão posterior do processo de regeneração do talo apartir das células do calo.

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Pollard, Carol L. Jones John R. "Influence of streambed substrate type and watershed properties on seston algal abundance." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/6115.

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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract, appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on October 9, 2009) Thesis advisor: Dr. John R. Jones. Includes bibliographical references.

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Steichen, Seth A., and Seth A. Steichen. "Tracking an Algal Predator: Monitoring the Dynamics of Vampirovibrio Chlorellavorus in Outdoor Culture." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/622836.

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The environmental conditions created in the Southwestern deserts of the United States are conducive to the production of green microalgae biomass, for use as a feedstock intended for conversion to carbon neutral liquid biodiesel. One promising heat-tolerant, rapidly-growing, high lipid content species is the chlorophyte, Chlorella sorokiniana (Shihira and Krauss, 1965) (isolate DOE 1412), which has been selected for pilot-scale production as part of a larger algal biofuels project to assess its potential for long-term productivity in open, outdoor monoculture production systems. Molecular analysis exposed the presence of the pathogenic bacterium, Vampirovibrio chlorellavorus (Gromov & Mamkaeva, 1972) causing infection and death of DOE 1412, which occurred most rapidly at air temperatures exceeding 34 °C. This Gram-negative bacterium has been reported to attach to and utilize the cellular contents of several Chlorella species, leading to yellowing and flocculation of algal cells, and death of the host. A quantitative PCR assay was developed to monitor pathogen accumulation using the 16S ribosomal RNA gene, in addition to the algal 18S ribosomal RNA gene for normalization. The assay is highly sensitive, with limits of quantification for the 16S and 18S gene targets calculated to be 19 and 131 copies, respectively. The qPCR assay was used to monitor several outdoor reactors inoculated with the DOE1412, throughout the warm season growth-to-harvest cycle to understand the disease cycle and inform disease management decisions. Further, the bacterium was monitored in paddlewheel DOE 1412 cultures treated with benzalkonium chloride (BAC), a biocide tested for the ability V. chlorellavorus attack of DOE 1412. The treatment resulted in a reduced growth rate for DOE 1412, but prolonged the duration of the production cycle resulting in increased total harvestable yield, compared to untreated control cultures.

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Su, Yanyan [Verfasser], and Brigitte [Akademischer Betreuer] Urban. "Settleable algal-bacterial culture for municipal wastewater treatment / Yanyan Su. Betreuer: Brigitte Urban." Lüneburg : Universitätsbibliothek der Leuphana Universität Lüneburg, 2012. http://d-nb.info/1034147862/34.

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Moheimani, Navid Reza. "The culture of coccolithophorid algae for carbon dioxide bioremediationn /." Access via Murdoch University Digital Theses Project, 2005. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20050901.140745.

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Moheimani, Navid Reza. "The culture of coccolithophorid algae for carbon dioxide bioremediation." Thesis, Moheimani, Navid Reza ORCID: 0000-0003-2310-4147 (2005) The culture of coccolithophorid algae for carbon dioxide bioremediation. PhD thesis, Murdoch University, 2005. https://researchrepository.murdoch.edu.au/id/eprint/206/.

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The culture of coccolithophorid algae is an attractive option for sequestration or recycling of CO2 as they can fix carbon by photosynthesis as well as in calcium carbonate scales known as coccoliths. They also produce high amounts of lipids which have a potential application as a renewable fuel. Five species of coccolithophorids (Pleurochrysis carterae, CCMP647, Pleurochrysis sp. CCMP1211, Gephyrocapsa oceanica CS-335/2, Emiliania huxleyi CCMP371, and Emiliania huxleyi CS-369) were screened for their ability to grow at high temperature. All species grew up to 28oC except E. huxleyi CS-369. However, Pleurochrysis sp. CCMP 1211 which was found to clump and can therefore not be recommended for large-scale cultivation. The salinity tolerance of these species was also examined. Growth of P. carterae, G. oceanica, and E. huxleyi in laboratory scale closed photobioreactors (plate, carboy, airlift, and tubular photobioreactors) showed the plate photobioreactor to be the best closed cultivation system. The highest productivities were achieved by P. carterae in the plate photobioreactor and were 0.54 g.L-1.d-1, 0.12 g.L-1.d-1, 0.06 g.L-1.d-1 for total dry weight, lipid and CaCO3 respectively. The growth of P. carterae and E. huxleyi was also examined in an outdoor raceway pond. The E. huxleyi culture was easily contaminated resulting in the loss of the culture in less than three weeks, but P. carterae grew well over a period of 13 months. The overall total dry weight productivity of P. carterae was 0.19 g.L-1.d-1 with lipid and CaCO3 contents of up to 33% and 10% of dry weight respectively. There was little protozoan and bacterial contamination. Medium pH increased to pH 11 during the day and was found to be a reliable variable for maintaining the health of the culture. A maximum pH achieved during the day of less than pH 8.5 indicated the imminent collapse of the culture. Heavy rain and low temperature were the main reasons for culture loss in mid winter, whereas high temperature during summer favoured P. carterae growth. A comparison of the growth of P. carterae and Dunaliella salina MUR8 in the raceway ponds showed no significant differences between these two species with regard to areal total dry weight productivity and lipid content. The effects of several limiting factors were also examined. A reduction in medium pH resulting from CO2 addition inhibited the growth of E. huxleyi in the plate photobioreactor, whereas P. carterae growth and productivities increased in the pH range of pH 7.7 to 8.0 in the plate photobioreactor and pH 9.1 to 9.6 in the outdoor raceway pond. The best operational pond depth for outdoor raceway culture of P. carterae was between 16 cm and 21 cm. Early morning temperatures, especially during the winter, highly affected the growth of P. carterae in the raceway pond, whereas artificially increasing the medium temperature improved the health of the culture but resulted in little increase in productivity. Photosynthesis of P. carterae was found to be highly inhibited by high oxygen concentration in the medium irrespective of temperature or irradiance. An economic model of P. carterae in a 63 ha raceway plant resulted in a cost for the biomass of between 7.35 Aus$.Kg-1 and 14.17 Aus$.Kg-1 depending on the harvesting method used.

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Moheimani, Navid Reza. "The culture of coccolithophorid algae for carbon dioxide bioremediation." Moheimani, Navid Reza (2005) The culture of coccolithophorid algae for carbon dioxide bioremediation. PhD thesis, Murdoch University, 2005. http://researchrepository.murdoch.edu.au/206/.

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The culture of coccolithophorid algae is an attractive option for sequestration or recycling of CO2 as they can fix carbon by photosynthesis as well as in calcium carbonate scales known as coccoliths. They also produce high amounts of lipids which have a potential application as a renewable fuel. Five species of coccolithophorids (Pleurochrysis carterae, CCMP647, Pleurochrysis sp. CCMP1211, Gephyrocapsa oceanica CS-335/2, Emiliania huxleyi CCMP371, and Emiliania huxleyi CS-369) were screened for their ability to grow at high temperature. All species grew up to 28oC except E. huxleyi CS-369. However, Pleurochrysis sp. CCMP 1211 which was found to clump and can therefore not be recommended for large-scale cultivation. The salinity tolerance of these species was also examined. Growth of P. carterae, G. oceanica, and E. huxleyi in laboratory scale closed photobioreactors (plate, carboy, airlift, and tubular photobioreactors) showed the plate photobioreactor to be the best closed cultivation system. The highest productivities were achieved by P. carterae in the plate photobioreactor and were 0.54 g.L-1.d-1, 0.12 g.L-1.d-1, 0.06 g.L-1.d-1 for total dry weight, lipid and CaCO3 respectively. The growth of P. carterae and E. huxleyi was also examined in an outdoor raceway pond. The E. huxleyi culture was easily contaminated resulting in the loss of the culture in less than three weeks, but P. carterae grew well over a period of 13 months. The overall total dry weight productivity of P. carterae was 0.19 g.L-1.d-1 with lipid and CaCO3 contents of up to 33% and 10% of dry weight respectively. There was little protozoan and bacterial contamination. Medium pH increased to pH 11 during the day and was found to be a reliable variable for maintaining the health of the culture. A maximum pH achieved during the day of less than pH 8.5 indicated the imminent collapse of the culture. Heavy rain and low temperature were the main reasons for culture loss in mid winter, whereas high temperature during summer favoured P. carterae growth. A comparison of the growth of P. carterae and Dunaliella salina MUR8 in the raceway ponds showed no significant differences between these two species with regard to areal total dry weight productivity and lipid content. The effects of several limiting factors were also examined. A reduction in medium pH resulting from CO2 addition inhibited the growth of E. huxleyi in the plate photobioreactor, whereas P. carterae growth and productivities increased in the pH range of pH 7.7 to 8.0 in the plate photobioreactor and pH 9.1 to 9.6 in the outdoor raceway pond. The best operational pond depth for outdoor raceway culture of P. carterae was between 16 cm and 21 cm. Early morning temperatures, especially during the winter, highly affected the growth of P. carterae in the raceway pond, whereas artificially increasing the medium temperature improved the health of the culture but resulted in little increase in productivity. Photosynthesis of P. carterae was found to be highly inhibited by high oxygen concentration in the medium irrespective of temperature or irradiance. An economic model of P. carterae in a 63 ha raceway plant resulted in a cost for the biomass of between 7.35 Aus$.Kg-1 and 14.17 Aus$.Kg-1 depending on the harvesting method used.

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Truxal, Laura T. "Characterization of novel compounds isolated from Karenia brevis cultures." View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-3/rp/truxall/lauratruxal.pdf.

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Henrich, Christian-Dominik. "Algal and bacterial nitrogen processing in a zero-discharge suspended-culture shrimp production system." Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1211390821/.

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Thesis (M.S.) -- Clemson University, 2008.
Title from first page of PDF file. Document formatted into pages; contains xxi, 174 p. ; also includes graphics (chiefly col.). Contains additional supplemental file.

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24

Beck, Kevin Moran. "Development of an Algal Diet for Rearing Juvenile Freshwater Mussels (Unionidae)." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/33017.

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Feeding selectivity by the rainbow mussel (Villosa iris) was examined for three age groups; 2-3 days old, 50-53 days old, and 3-6 years old. The mussels were fed an algal diet consisting of Scenedesmus quadricauda (22.3 - 44.5 Æ Ã m), Nannochloropsis oculata (2.8 Â¡V 8.1 Æ Ã m), and Selenastrum capricornutum (3.6 Â¡V 8.5 Æ Ã m) in equal cell densities. The change in relative abundance of each algal species within feeding chambers over a 5 hr feeding trial was used to discern selectivity. At the conclusion of the feeding trials, the gut contents of mussels were analyzed for preferential ingestion. The mussels selected for N. oculata and S. capricornutum over S. quadricauda (p < 0.05). This may be an indication of particle size-dependent selection. Feeding trials also suggest that selectivity by the rainbow mussel does not change with age. Gut content analyses showed a preferential ingestion of algae, in the sequence N. oculata, S. capricornutum, then S. quadricauda. The suitability of two algal diets, S. quadricauda and N. oculata, for rearing captive juveniles of V. iris in 145-L recirculating culture systems was compared. Juveniles were fed their assigned diet at a density rate of approximately 30,000 cells/ml for 42 days, and sampled weekly for percent survival and shell length. Regardless of diet, juvenile survival decreased rapidly after 21 days, and growth did not exceed approximately 450 Æ Ã m. High mortality rates and slow growth of juveniles was likely due to inadequate diets. Juveniles that were fed S. quadricauda lacked chlorophyll coloration in their guts, indicating that the juveniles did not ingest this species of algae. Colonies of S. quadricauda were likely too large for the juveniles to ingest. The gut content of juveniles fed N. oculata showed chlorophyll coloration, indicating that the juveniles ingested this species, but N. oculata may have been difficult for the juveniles to assimilate. Under the culture conditions provided, survival and growth did not compare favorably to those of other studies with V. iris. Newly metamorphosed juveniles of V. iris were reared in 145-L recirculating culture systems containing sediment (< 600 Æ Ã m) of two depths, 5 mm and 15 mm. Mussels were fed a bi-algal diet of Nannochloropsis oculata and Neochloris oleoabundans. Survival differed significantly between treatments (p=0.04), and was higher for juveniles reared in 5 mm of sediment over a 40-day period. Growth was not significantly different between treatments. After 40 days, juveniles achieved a mean length of approximately 578 Æ Ã m in both treatments. Survival and growth of juveniles compared favorably to those of other culture studies using juveniles of V. iris. A shallow layer of sediment is recommended for the culture of juvenile mussels.
Master of Science

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25

King, Leighton R. "The Response of Utah Lake's Plant and Algal Community Structure to Cultural Eutrophication." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7631.

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Human activities have long had a negative impact on the water quality of freshwater lakes around the world. Utah Lake, located in north-central Utah, has been a subject of such impacts, as the lake experiences recurrent harmful algal blooms during the summer months. Lake warnings and closures have made the public increasingly aware of the ecological and economic impact of these blooms. The objectives of this study were to: 1) compare historical and present-day water quality and ecosystem conditions using environmental data contained in sediment cores, 2) identify whether, and when, Utah Lake transitioned from clearwater to turbid conditions, and 3) incorporate historically-validated lake plant community structure models into establishing forward-thinking lake management targets. The first two objectives will guide lake remediation efforts by providing insight into where lake managers should set our water quality goals and help identify the main driver(s) of eutrophication in Utah Lake. Environmental data from sediment cores indicate a transition in the lake’s recent history, marking a shift to greater phytoplankton dominance, which I attribute to the introduction of invasive common carp around 1881. The third objective provides management and restoration efforts with the water clarity requirements for returning the lake to its historical ecological state.

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26

Faria, Tatiana Carvalho. "Desempenho de bioestimulantes e sua viabilidade econômica na cultura da soja." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/6943.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The use of biostimulants has been widely applied in agricultural production, in soybean especially, and perform an important role in the growth and development of plants. The present study objectified to evaluate the biostimulants in soybean, about the application time and the environment, considering the agronomic aspects, productivity and economic viability. Two experiments were implanted, one in the greenhouse and other in the field. The design was completely randomized, factorial 6 x 3 with 4 repetitions. The treatments were: control, without product application; Stimulate® , 250 mL ha-1 ; Matrix G® , 200 mL ha-1 ; Vitakelp® , 250 mL ha-1 ; Agrostemin® , 30g ha-1 ; Improver® , 120 mL ha-1 . The times of application were in seed treatment, to 40 or 60 days after sowing. In the greenhouse, the control, Agrostemin® and Improver® obtained the same mean of the first legume insert and were higher to Vitakelp® . In the dry root mass, the Matriz G® was higher than Vitakelp® . In the field, in relation to first legume insert the Agrostemin® was better than the Improver® and Stimulate® , the Matriz G® surpassed the Improver® and the application via seed and 60 days after sowing were better. In relation to plant height in seed treatment, the control and the Stimulate® were better than Matriz G® and the Improver® . When applied 40 days after sowing, the Stimulate® had greater height than the Matriz G® . In this variable the best time for of the products application was 40 days after sowing. In number of branches, in the seed treatment, the control and the Stimulate® had more branches than Vitakelp® and Improver® . In the analysis of joint variance of the experiments the height of first legume insert, number of pods, grains and branches per plant, grain mass and productivity were better at greenhouse. Plant height stood out in the field. All treatments were better in the field at plant height and better at greenhouse in grain mass and productivity. It is concluded that the climate, nutritional and health conditions favorable for the crop cycle attenuate the effects of biostimulants in plants. The first legume insert, plant height, root dry mass and number of branches per plant, the biostimulants contribute positively. The application time influences the first legume insert, plant height and number of branches per plant, increasing them. Growing in a greenhouse brings better results. The use of biostimulants is not economically viable.
O uso de bioestimulante tem sido amplamente aplicado na produção agrícola, especialmente em soja, e desempenha um papel importante no crescimento e desenvolvimento da planta. O presente trabalho objetivou avaliar bioestimulantes em soja, segundo a época de aplicação e ambiente, atentando para os aspectos agronômicos, produtividade e viabilidade econômica. Foram implantados dois experimentos sendo um em ambiente com telado e outro no campo. O delineamento foi inteiramente ao acaso, esquema fatorial 6 x 3, com 4 repetições. Os tratamentos foram: testemunha, sem aplicação de produto; Stimulate® , 250 mL ha-1 ; Matriz G® , 200 mL ha-1 ; Vitakelp® , 250 mL ha-1 ; Agrostemin® , 30g ha-1 ; Improver® , 120 mL ha-1 . As épocas de aplicação foram: em tratamento de sementes, aos 40 ou 60 dias após o semeio. Em telado, a testemunha, o Agrostemin® e o Improver® obtiveram a mesma média de altura de inserção de primeira vagem e foram superiores ao Vitakelp® . Em relação à massa seca de raiz, o Matriz G® foi superior ao Vitakelp® . No campo, em relação à altura de inserção de primeira vagem o Agrostemin® foi melhor que o Improver® e o Stimulate® , o Matriz G® superou o Improver® e a aplicação via semente e com 60 dias após o semeio foram melhores. Em relação à altura de planta, em tratamento de sementes, a testemunha e o Stimulate® foram melhores que o Matriz G ® e o Improver® . Quando aplicados aos 40 dias após o semeio, o Stimulate® teve maior altura que o Matriz G® . Nesta variável a época melhor para aplicação dos produtos foi aos 40 dias após o semeio. Em número de ramos por planta, no tratamento de sementes, a testemunha e o Stimulate® tiveram mais ramificações que o Vitakelp® e o Improver® . Na análise de variância conjunta dos experimentos a altura de inserção de primeira vagem, número de vagens, grãos e ramos por planta, massa de grãos e produtividade foram melhores em ambiente com telado. A altura de planta se destacou no campo. Todos os tratamentos foram melhores no campo em altura de planta e melhores em telado na massa de grãos e produtividade. Concluiu-se que as condições climáticas, nutricionais e sanitárias favoráveis durante o ciclo da cultura atenuam os efeitos dos bioestimulantes nas plantas. A altura de inserção de primeira vagem, altura de planta, massa seca de raiz e número de ramos por planta, os bioestimulantes contribuem de forma positiva. A época de aplicação influencia, aumentando a altura de inserção de primeira vagem, altura de planta e número de ramos por planta. O cultivo em ambiente com telado traz melhores resultados. Não é viável economicamente o uso de bioestimulantes.

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27

Garvey, Alyssa. "Next-generation sequencing, morphology, and culture-based methods reveal diverse algal assemblages throughout the Florida springs." UNF Digital Commons, 2019. https://digitalcommons.unf.edu/etd/899.

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Algae are a group of highly diverse photosynthetic organisms found in variety of habitats. As the primary energy base in ecosystems, knowledge of the diversity and presence of certain algal lineages is paramount to our understanding of the trophic state of aquatic habitats. In recent years, the state of Florida has seen an increase of both marine and freshwater algal blooms. Similarly, filamentous algae have begun outcompeting vascular macrophytes throughout many of Florida’s springs as nutrient enrichment from anthropogenic sources increases. Traditionally, the Florida algal spring communities have been assessed using classic morphological methods, which may underrepresent the true biodiversity present. Therefore, the goal of this study was to conduct a more complete diversity assessment implementing next-generation sequencing techniques (NGS) with morphological analyses and culturing methods. While morphological methods identified a wide variety of algal taxa, belonging to 4 phyla (Bacillariophyta, Charophyta, Chlorophyta, and Cyanobacteria), next-generation sequencing techniques provided greater detail of the diatom community. This is particularly important as many diatom taxa are used as indicators of water quality. We noted discrepancies between these two methods, highlighting how NGS techniques may complement the use of morphological analyses when analyzing algal diversity in this system. Culturing methods also revealed the presence of two taxa new to science (Nodosilinea fontisand Brasilonema variegatus), indicating these springs may represent a potential source of novel cyanobacteria. Taken together, this study showcases Florida springs are rich in algal diversity and a combination of methods is required for more complete biodiversity assessments. Future studies implementing such methods will aid in the preservation and conservation of these ecosystems.

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28

Cilliers, Anneke. "The treatment of brewery effluent using an integrated high rate algal ponding system." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1005177.

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The application of high rate algal ponds (HRAP) in the treatment of brewery effluent that met the South African Department of Water Affairs and Forestry's (DWAF) general limits for discharge into a natural water resource of 1998 were tested during a lO-month baseline phase, followed by an 11-month optimization phase. The objective of the baseline phase was to monitor the seasonal performance of HRAPs. The hydraulic retention time (HRT) fluctuated between 11.16 d and 12.00 d in HRAPs. The chemical oxygen demand (COD) increased from 130.12 ± 6.94 mg/L (post-AD), to 171.21 ± 7.99 mg/L (post-HRAP) . The presence of algal cells and evaporation contributed towards an increase in post-HRAP COD. The ammonia (NH₄-N) concentration decreased from 46.59 ± 2.47 mg/L (post-AD), to 1.08 ± 0.12 mg/L (post-HRAP). The nitrite (NO₂- N) concentration remained below 1.00 mg/L in post-pilot plant AD, post-PFP and post-HRAP effluent. The phosphate (PO₄-P) concentration decreased from 29.81 ± 1.39 mg/L (post-AD) to 17.30 ± 1.16 mg/L PO₄-P. The objective of the optimization phase was to manipulate the HRT to achieve the maximum treatment rate that met the DWAF general limits for discharge into a natural water resource of 1998. Nitrogen (as NH₄-N, NO₃-N, NO₂-N) removal efficiency was used as an indicator of nutrient removal success. HRT was influenced by season. The optimal HRT for autumn was 4.30 d at a temperature of 20.53ºC in HRAP A2 (heated) and 18.96ºC in HRAP B2 (ambient). The optimal HRT for summer was 2.74 d at 29.90ºC in HRAP A2 (heated) and 26.36ºC in HRAP B2 (ambient). The COD decreased from 152.33 ± 4.85 mg/L (post-AD) to 95 .00 ± 3.75 mg/L (post-HRAP A2), and to 100.82 ± 5.93 mg/L (post-HRAP B2). The incoming NH₄-N concentration decreased from 42.53 ± 1.38 mg/ L (post-AD), to 1.70 ± 0.81 mg/ L (post-HRAP) . The nitrate (NO₃-N) concentration post-HRAP was 12 - 14 mg/L. The main methods for NH₄-N removal were probably NH₄-N volatilization through algal uptake. HRAPs were able to lower nitrogen and phosphorous concentrations to within the DWAF limits under normal operating conditions. It is recommended that HRAP treated brewery wastewater be used for irrigation after salt removal, or alternatively, for groundwater recharge . Regulatory exemptions would be required for higher than permitted COD and EC concentrations to enable these actions.

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29

Misciattelli, Natalia. "Control of pathogenic bacteria in marine larval culture systems." Thesis, Bangor University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311387.

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30

Janocka, Déborah. "Culture in vitro de la Fucale Pelvetia canaliculata : applications à la production de biomasse algale et à la cryoconservation des semences." Caen, 2009. http://www.theses.fr/2009CAEN2073.

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Pelvetia canaliculata est une Phéophycée commune des côtes de la Manche. Son exploitation industrielle n’est pas actuellement envisageable en raison de ses peuplements limités nécessitant alors l’élaboration de systèmes de micropropagation. La production de biomasse algale de Pelvetia a été développée à partir des cellules somatiques (protoplastes, explants) et des semences naturelles (zygotes) en fonction de la période du cycle de développement. La cryoconservation des zygotes permet d’envisager la constitution d’un stock de semences disponible toute l’année. La mise au point d’une solution enzymatique a permis la production en routine de protoplastes avec des rendements atteignant 107 protoplastes. G-1 de matière fraîche à partir des apex. L’étude des paramètres physicochimiques de leur régénération a abouti à la formation de la paroi squelettique puis au déclenchement de bourgeonnements et de divisions cellulaires traduisant une reprise du programme morphogénétique. La culture d’explants sur milieu solide a induit la néoformation de bourgeons à partir des différentes zones du thalle, notamment de la zone sous-apicale. L’amélioration du protocole a été initiée. Les facteurs contrôlant la libération synchrone et massive des gamètes de Pelvetia et la production des zygotes ont été identifiés. La séquence du développement embryonnaire in vitro a été décrite jusqu’au stade plantule mettant en évidence l’absence de polarité du zygote et d’une première division asymétrique. Le protocole de cryoconservation des zygotes mis au point permet d’obtenir une viabilité des embryons après réchauffement d’environ 60% au bout de 28 jours de culture et leur régénération en plantules
Pelvetia canaliculata is a common Phaeophyceae of the French Channel coast. For the time being its industrial exploitation is not possible due to its restricted wild populations it is requiring the elaboration of systems of micropropagation. The production of algal biomass of Pelvetia has been developed from somatic cells (protoplasts, tissue culture) and from natural seeds (zygotes) according to the period of the life cycle. The cryopreservation of zygotes has been also developed allowing to the establishment of a seedstock available throughout the year for macroalgal culture. The composition of an enzyme solution has been determined in order to produce reliably protoplasts from apical regions of the thallus, protoplasts yields reaching 1 x 107 protoplasts per gram of fresh weight. The study of the physicochemical parameters of the protoplast regeneration has led to the synthesis of the cell wall followed by buddings and cell divisions indicating a new start of a morphogenetic program. Tissue culture on solid medium induced buds regeneration from the different regions of the thallus, particularly from subapical explant. The improvement of the protocol has been initiated. The factors involved in the synchronous and massive discharge of gametes of Pelvetia and the production of zygotes have been identified. The sequence of the embryonic development in vitro has been described until the plantlet stage revealing the absence of a zygotic polarity and of a first asymmetric division. A protocol of cryopreservation of zygotes has been established. The viability of the cooled embryos after thawing was about 60% after 28 days of culture and they developed into plantlets

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31

Sathish, Ashik. "Biodiesel Production from Mixed Culture Algae Via a Wet Lipid Extraction Procedure." DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1372.

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With world crude oil reserves decreasing and energy prices continually increasing, interest in developing renewable alternatives to petroleum-based liquid fuels has increased. An alternative that has received consideration is the growth and harvest of microalgae for the production of biodiesel via extraction of the microalgal oil or lipids. However, costs related to the growth, harvesting and dewatering, and processing of algal biomass have limited commercial scale production of algal biodiesel. Coupling wastewater remediation to microalgal growth can lower costs associated with large scale growth of microalgae. Microalgae are capable of assimilating inorganic nitrogen and phosphorous from wastewater into the biomass. By harvesting the microalgal biomass these nutrients can be removed, thus remediating the wastewater. Standard methods of oil extraction require drying the harvested biomass, adding significant energetic cost to processing the algal biomass. Extracting algal lipids from wet microalgal biomass using traditional methods leads to drastic reductions in extraction efficiency, driving up processing costs. A wet lipid extraction procedure was developed that was capable of extracting 79% of the transesterifiable lipids from wet algal biomass (16% solids) without the use of organic solvents while using relatively mild conditions (90 °C and ambient pressures). Ultimately 77% of the extracted lipids were collected for biodiesel production. Furthermore, the procedure was capable of precipitating chlorophyll, allowing for the collection of algal lipids independently of chlorophyll. The capability of this procedure to extract lipids from wet algal biomass, to reduce chlorophyll contamination of the algal oil, and to generate feedstock material for the production of additional bio-products provides the basis for reducing scale-up costs associated with the production of algal biofuels and bioproducts.

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32

Wilson, Misheka. "Cross Flow Filtration for Mixed-Culture Algae Harvesting for Municipal Wastewater Lagoons." DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1162.

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The transesterification of lipids extracted from algae makes up the third generation of biodiesel production. The city of Logan, Utah, proposes that the algae used from the 460-acre wastewater pond could potentially be used for the production of biofuel that could serve as transportation fuel for the City solid waste vehicles. Separating the algae from the Logan Lagoon wastewater is the most expensive portion of the biodiesel process and the application of chemical flocculation can significantly increase costs and potentially interfere with biodiesel production. Cross flow filtration has been identified for algae harvesting, and experiments were conducted to evaluate materials and operating conditions for separating and harvesting algae from the Logan Lagoon system. Two cross flow filtrations units were used to conduct experiments. A pilot-scale cross flow filtration unit provided by WesTech, Inc., Engineering (Salt Lake City) with a 0.2-micron nylon membrane mesh was used for mixed-culture algae harvesting. In addition, a bench scale cross flow filtration unit was provided, and tests were conducted to further examine the effectiveness of cross flow filtration on pure-culture algae harvesting. A 1-micron nylon, 5-micron nylon and 5-micron polyester mesh were used with this system. The WesTech, Inc., Pilot Scale System demonstrated that the type of membrane used was critical for effective algae harvesting. Test results showed that the algal cake that developed on the membrane and that the amount of algae harvested decreased with flux. The bench scale unit demonstrated that more algal cells were collected when a membrane of a larger pore size was used. The 1-micron nylon mesh proved to be the most effective at concentration algae. The 5-micron polyester mesh was shown to be more effective than the 5-micron nylon mesh. The results in this thesis show that cross flow filtration is a feasible option for the City of Logan Environmental Department and is a technical option for algal harvesting for biofuel production.

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33

Grace, Sean Patrick. "Ecomorphology of the temperate scleractinian astrangia poculata : coral-macroalgal interactions in Narragansett Bay /." View online ; access limited to URI, 2004. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3145417.

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34

Craggs, Rupert Justin. "Wastewater nutrient removal by marine microalgae." Thesis, University of St Andrews, 1994. http://hdl.handle.net/10023/14217.

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Although, microalgal wastewater treatment systems represent an efficient and economical alternative to conventional processes, the use of marine microalgae to remove nutrients from wastewaters has not been extensively researched and few studies have been made in temperate and high latitude areas, where climate may limit treatment. In this study, 102 marine microalgal species, including 66 local endemic isolates from St Andrews Bay, Fife, Scotland, were screened under batch and continuous culture. Species were selected for their ability to remove high concentrations of ammonium and ortho-phosphate from primary treated sewage (diluted 1:1 with sterile seawater) while remaining dominant in culture. Abiotic removal of ammonium and ortho-phosphate at high pH was found to be low from saline media, indicating that much of the nutrient removal from the seawater:wastewater mixture was by algal uptake. Many of the best-treating species grew over a wide range of temperature (10-25 °C), and their growth was not inhibited by the low salinity of the 1:1 diluted wastewater. Seven best-treating species continuously removed >80 % ammonium and >70% ortho-phosphate when cultured in 20 litre mini-ponds (modelled on high-rate ponds) under ambient summer conditions over two weeks. These were all endemic isolates including six bacillariophyceaen isolates (of which three were strains of Phaeodactylum tricornutum), and a species of the cyanophyceaen Oscillatoria. Two isolates (Oscillatoria and an unidentified bacillariophyceaen SA91B33) with adherent properties, continuously removed 100 % of both ammonium and ortho-phosphate when tested in a corrugated raceway designed to provide a large surface area for attachment. Preliminary experiments further showed the best-treating species to be capable of removing nutrients from eel aquaculture effluent. The abilities of marine microalgal species to remove high concentrations of nutrients, remain in unialgal culture and grow over a range of environmental conditions are indicative of their potential for use in wastewater treatment systems in temperate areas.

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35

Whiston, Andrew James. "Uptake of heavy metals by marine microalgae, with a view towards wastewater detoxification." Thesis, University of St Andrews, 1997. http://hdl.handle.net/10023/14212.

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Treatment of waste water by freshwater microalgae is rapidly becoming a popular sewage treatment practice throughout the world, but only a few studies have been made into the use of marine strains or of their potential for heavy metal removal. This study examines the heavy metal tolerance of a range of marine microalgal species and examines some of the biological processes involved in metal uptake. Initially over 350 marine microalgal species/isolates were screened for (a) growth in the presence of heavy metals (10 ppm), (b) growth in the presence of wastewater (1:1 sewage : seawater), and (c) heavy metal uptake. Of the microalgae examined, only one isolate, Tetraselmis sp. (TSAW92) was found to satisfy all of the screening conditions. Metal uptake was found to be a biphasic process, with an initial rapid saturable metabolism-independent stage followed by a slower nonsaturable metabolism-dependent stage. Using a novel filtration technique metal uptake was measured at ten second intervals. The results show that most of the metal uptake occurs within one minute after exposure. The second stage of metal uptake was found to be associated with the extracellular release of up to three copper binding proteins of ca. 28, 30, 55 kDa. Protein release was specifically induced by the presence of heavy metals and was not due to metal mediated increases in cell membrane permeability. Two practical applications of Tetraselmis sp. (TSAW92) metal uptake were investigated. First dried biomass was evaluated in a simple packed column. Second, live cells were grown on a wastewater treatment raceway (2m), upstream of a Dunaliella salina stocked nutrient removal raceway. Dried Tetraselmis sp. (TSAW92) was capable of removing copper from a 1:1 seawater : sewage solution to a final loading of 30% at an efficiency of approaching 100%. Over four weeks live TSAW92 removed 100% of the applied copper to a final loading of 37%, and, after the second stage, the raceway was found to remove 95% of the applied nitrogen and 87% of the applied phosphorus. This thesis shows that marine microalgae are capable of removing heavy metals from wastewater in vitro, on raceways, and as dried biomass. Live marine microalgae on raceways were further found to remove inorganic nutrients (nitrogen and phosphorous). In addition work is presented which suggests that copper uptake by the marine chlorophyte Tetraselmis sp. (TSAW92) is mediated through extracellular copper binding proteins.

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36

Hodgson, Paul Andrew. "The effects of environmental variables upon the lipid class and fatty acyl composition of a marine microalga, Nannochloropsis oculata (Droop) Eustigmatophyceae (Hibberd)." Thesis, University of Stirling, 1990. http://hdl.handle.net/1893/25425.

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Detailed analyses of the lipid class and fatty acid composition were carried out for the marine microalgal species Nannoch/oropsis oculata (Droop) (CCAP strain no. 849/1) of the division Eustigmatophyceae (Hibberd). The alga was grown in batch and continuous culture using a novel culturing apparatus, the cage culture turbidostat, the construction of which is detailed in full. The total lipid extract yielded by the alga varied in a growth-phase dependent manner within the range 25 % to 80 % of the lyophilised cell mass. Of this between 40 % and 70 % was recovered as fatty acid methyl esters (FAME) upon transesterification. The total fatty acid composition of N. oculata consisted mainly of 16:0, 16:1 and 20:5(n-3), these three fatty acids often accounting for greater than 80 % of the total fatty acid mass. Between 9 % and 50 % of the mass of total FAME was accounted for by 20:5(n-3), the balance being accounted for by variations in the relative proportions of 16:0, 16:1, 18:1, 18:2 and 20:4. During periods of low cellular division rate, such as the lag- and stationary-phases, the proportion of polyunsaturated fatty acids (PUFA) (mainly 20:5(n-3» decreased. The total fatty acids became increasingly saturated as higher proportions of shorter chain length fatty acids accumulated, mainly in triacylglycerols (TAO). Increased cellular proportions of total lipid resulted from TAO accumulation which occurred on account of preferential partitioning of carbon into TAO biosynthesis whilst cellular division was suspended. The fatty acid composition of the TAO was more saturated at high synthesis rate and vice-versa at lower rates. The galactolipids, monogalactosyldiacylglycerol (MODO) and digalactosyldiacyl glycerol (DODO) were rich in 20:5(n-3) during exponential cell division containing up to 77 % and 53 % 20:5(n-3) respectively. Phosphatidylcholine (PC) was the only cl~s to contain significant proportions of CIS fatty acids during exponential growth, thus implicating its involvement in the acyl chain elongation reactions between the Cl6 and C20 fatty acids. Culture incubation temperature in the range 5 °C to 25°C did not influence the fatty acid composition of N. oculata. The effect of temperature upon culture dynamics at the lower culture incubation temperatures gave an apparent decrease in the PUFA content of the total fatty acid at a given point on the cultures growth curves. By expressing the data in tenns of culture doubling periods during the exponential-phases of growth it was found that temperature had no real effect upon fatty acid unsaturation or chain length. at either the total or the individual lipid class FAME level after the cells had passed through five doubling periods. Increasing the culture medium salinity from one quarter to one and a half times that of normal seawater decreased the un saturation and chain length of the fatty acids at both total and individual lipid class levels. The change resulted from the progressive accumulation of 18:1 and 18:2"at the expense of 20:5. Variation of salinity did not affect the dynamics of the cultures in the same respect as temperature in that a lag-phase was not observed on the cultures growth curves. However. such a phase was evident in the fatty acid profile of the cells in the period following inoculation. The 'effects of culture illumination intensity in the range 45 Jill m-2 sec-I to 170 Jill m 2 sec-! were examined under continuous culture conditions using the cage culture turbidostat Accumulation of saturated TAG by the cells at the higher illumination intensities gave an apparent decrease in the rate of PUFA biosynthesis. The polar lipid classes were found to be more highly unsaturated at higher illumination intensities. At lower illumination intensity TAG accumulation was reduced and the total fatty acid composition was accordingly more unsaturated. The fatty acid composition of the TAG component was more unsaturated but those of the polar lipid classes were less unsaturated than at higher illumination intensity. Increased illumination increased the degree of un saturation of the polar lipid cl~sses. Excess fixed carbon was partitioned into TAG biosynthesis. primarily as 16:0 and 16:1. The net accumulation of this lipid class even at high cell division rates resulted in a low overall unsaturation level. The effects of decreasing nitrate concentration in the range 1.0 mM N03 - to 0.001 mM N03 - had a similar basis to those of illumination in that the changes in the total fatty acid composition were largely governed by the rate of TAO accumulation. At high nitrate concentrations the cellular division rate was relatively high and the proportion of TAO in the total lipid extract was low. Consequently, both total and individual lipid classes contained high proportions of unsaturates, particularly 20:5(n-3). However, when the nitrate concentration was decreased, such that it began to limit the rate of cellular division, TAG accumulated Cursory analyses of the molecular species of the galactolipid classes, MODO and DODO, and phospholipid class PC are presented. The effects of environmental variables are discussed in tenns of the changes which may occur in the growth phase distribution of the cells in asynchronous culture, along with the concommitant changes in the lipid composition of the cells. The potential linkage of the elongation and desaturation reactions with both MODO and PC is also discussed briefly with reference to future research.

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Kimono, Diana Agnes. "The production of Omega 3 fatty acids by a mixed microalgae culture." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/6498.

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Background and Aim: Microalgae are a potential economical source of omega-3 fatty acids, which are known for their health benefits. Omega-3 fatty acids derived from microalgae are however still expensive due to high costs involved in production. These costs can partly be attributed to cultivation of microalgae in unialgal cultures, which are prone to contamination, difficult to scale up and require stringent control of growth conditions. This study therefore is aimed to investigate the feasibility of using a mixed microalgae culture for the production of omega-3 fatty acids. Methods and materials: The microalgae were grown under uncontrolled conditions in a hanging-bag photo-bioreactor, with only the phosphorus-nitrogen ratio (P:N-ratio) varied. Variations in the different population proportions in the culture were studied and related to the biomass, total fatty acid and omega-3 fatty acid productivity of the culture. Finally, a comparison was made between the results obtained in this study and similar studies found in literature. Results and discussion: The mixed culture used was composed of several green microalgae, whose proportions varied with P:N-ratio, season, and age of the culture. Different interactions between the populations were observable, and these were thought to influence the culture’s biomass, total fatty acids (TFAs) and omega-3 fatty acid productivity. The TFA content of the culture was ~10-20% by the end of the exponential phase, depending on the nutrients supplied. The fatty acids were composed of mostly unsaturated fatty acids, the majority of which were omega-3 fatty acids; C18:3ω3 (up to 50% of TFA), C16:4ω3 (up to 15%) and C18:4ω3 (up to 5%). Other fatty acids observed included C16:0 (up to 25%), C18:1ω9/C18:1ω8 (up to 20%), C18:2ω6 (up to 5%), traces of C18:0, C18:3ω6, C17:0, C16:3ω3 and C16:1ω7 were also detected. The presence of these fatty acids was found to vary depending on season, P:N-ratio, and age of the culture. When compared to studies in the literature, the mixed culture was found to perform better than, or as well as reported studies, where unialgal cultures were cultivated under controlled laboratory conditions. Conclusion: In view of the reported advantages of cultivating mixed cultures, the production of omega-3 fatty acids via such cultures appears attractive. More research however is needed to optimise the culture; study interactions between the organisms and their effect on biomass, total fatty acid and omega-3 fatty acid productivity. Finally, the economic implications of using mixed cultures need to be evaluated as well.

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Portugal, Isabel Campos. "Avaliação do crescimento de microalgas importantes para aquicultura cultivadas com diferentes concentrações de nutrientes." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/94204.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Aquicultura, Florianópolis, 2010
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Dentre as numerosas aplicações comerciais do uso de microalgas podemos destacar sua importância na aqüicultura onde podem ser empregadas como fonte primária de alimento para larvas, organismos jovens e até de adultos de moluscos, camarões e peixes marinhos, uma vez que, o elevado valor nutricional das microalgas justifica sua necessidade na alimentação destes organismos. Muitos fatores influenciam o crescimento das microalgas, sendo que, a disponibilidade de nutrientes é bastante relevante nesse aspecto. Para determinar o crescimento das culturas das microalgas Thalassiosira weissflogii, Chaetoceros muelleri, Isochrysis sp. e Pavlova sp. quando cultivadas com diferentes concentrações de nitrogênio e fósforo durante todo o cultivo, foram desenvolvidos cultivos experimentais com essas espécies. As espécies foram cultivadas em meio de cultura Guillard (1975) e a diferença dos tratamentos foi a quantidade de nitrogênio e fósforo utilizada nas soluções estoques para compor o meio de cultivo. Os parâmetros de crescimento analisados foram a densidade celular máxima, o tempo de cultivo e a velocidade de crescimento. Foi aplicado um delineamento uni-fatotorial para blocos casualizados.Os dados obtidos foram submetidos à analise de variância fatorial (Anova com P<0,05) e quando necessário ao Teste de Comparação de Médias de TuKey (p<0,05). Quanto ao crescimento das culturas o emprego do meio f - com o dobro da concentração de nitrato de sódio e de fosfato de sódio descrita em Guillard (1975), promoveu uma maior densidade celular nas culturas de Thalassiosira weissflogii, (66,7 x 104 cel/mL) Chaetoceros muelleri, (1566,7 x 104 cel/mL) Isocrysis sp (1903,3 x 104 cel/mL) e Pavlova sp (2362,3 x 104 cel/mL). (p<0,05) Quanto ao tempo de cultivo e a velocidade de crescimento não houve diferença significativa para nenhuma das espécies (p<0,05).

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39

Gernigon, Vincent. "Modélisation multi-échelle de la culture de microalgues." Thesis, Toulouse, INSA, 2020. http://www.theses.fr/2020ISAT0008.

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S'inscrivant au sein du projet PLAISIR qui vise à la commercialisation d'outils de production de microalgues alimentaires, l'objectif du présent travail est d'aider à la conception et au dimensionnement de ces outils de production : les photobioréacteurs. Pour cela, on procède à la modélisation du comportement de la phase biologique et des propriétés du réacteur afin d'être capable de simuler la croissance de la biomasse. Le travail de décompose en deux parties. La première cherche à mettre en évidence les aspects du procédé ayant un impact sur la cinétique de croissance, puis à les quantifier. On s'appuie en premier lieu sur la littérature, puis sur plusieurs campagnes expérimentales dans le but d'affiner les connaissances aux cas particulier de notre souche (Arthrospira Platensis alias Spiruline). La seconde étape consiste, pour un procédé donné (i.e. réacteur + protocole), à déterminer les conditions réactionnelles correspondantes et ainsi pouvoir utiliser les modèles cinétiques établis précédemment. La plus-value de la démarche se trouve sur deux niveaux. La première se situe dans l'approche multi-échelle des phénomènes, à savoir que l'on se place ici à l'échelle de la cellule, tant pour l'écriture des cinétiques de croissance que pour les conditions réactionnelles. Une telle approche permet de prendre en compte l'impact du réacteur lui-même, notamment due aux hétérogénéités locales qu'il contient. On améliore ainsi l'acquitté des simulations, en particulier face aux changements d'échelles : du laboratoire vers la production. L'autre aspect important, est de se placer dans un contexte multiphysique ou les différents phénomènes sont fortement couplés. L'étude tente donc de rendre compte des conséquences des paramètres opératoires en interactions, plutôt que considérés individuellement. Le travail s'est alors déroulé autours deux thématiques : l'étude de l'évolution de la composition du milieu d'un côté et l'étude l'exposition à la lumière de l'autre. Et met alors en évidence que l'écriture de la seule consommation des nutriments par la biomasse ne permet pas de décrire certains résultats sans y ajouter les équations propres aux réactions entre les constituants du milieu lui-même. Il est aussi proposé un modèle et une méthode pour décrire comment le mélange dans le photobioréacteur joue sur la croissance des microalgues via l'éclairement du volume réactionnel. A partir de quoi sont tirées des euristiques pour optimiser le procédé à travers ces trois points (milieu de culture, mélange et éclairement)
In the frame of the PLAISIR project, which is aiming at the commercialization of alimentary microalgae production devices, the objective of the present work is to improve the design of this production devices, named photobioreactors. We proceed to the modelitasion of the biological phase and of the properties of the reactor in order to simulate the biological growth. It is a two steps work. Firstly, it is about to highlight which ones of the process parameters that have an impact on the growth kinetic, then quantify them. It rely on a bibliographic study and after that on several experimental campaigns to refine the knowledge to the peculiar case of our strain (Arthrospira Platensis aka. Spirulina). The second step consist in the calculation reactional conditions in given process, and so enable the use of the previously determined kinetic models. This work benefit from a two-level added value. The first one is the multi-scale approach of the phenomena; this is to say that we write both the kinetic and the reactional conditions at the cell-scale. Such an approach enables to take into account the effect of the reactor itself, for instance thanks to the local heterogeneities it contains. We so improve the accuracy of the resulting simulations, especially in front of different reactor scales (laboratory one, vs. production one). The other aspect is to considerate the issue on a multi-physic way, because all the phenomena are strongly coupled each-others. The work is thus trying to depict the impact of the gathered parameters rather than to the same ones taken separately. The study then focuses on two topics: the evolution of the composition of the culture medium and the biomass exposition to the light. It is shown that the mere consumption of the nutrient by the biomass is insufficient to predict all the results without the addition of the inter-components chemical reactions. It is also proposed a methodology to describe how the mixing impact of the growth speed through the lighting of the vessel. Finally, some heuristics are deduced to optimize the process through this three points, namely: culture medium, mixing and lighting

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Wong, Yee Keung. "Feasibility of using Chlorella vulgaris for the production of algal lipids, for advancement towards a potential application in the manufacture of commodity chemicals and the treatment of wastewater." HKBU Institutional Repository, 2016. https://repository.hkbu.edu.hk/etd_oa/254.

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Driven by the increase in industrialization and population, the global demand of energy and material products is steadily growing. Microalgae have come into prominence in the past several decades due to their ability to utilize solar energy to fix atmospheric carbon dioxide, and produce biomass and lipids at productivities much higher than those possible with terrestrial biomass. The main objective of this research is to maximize the biomass and lipid production of Chlorella vulgaris by varying different external conditions so as to achieve the ideal feedstock for the production of commodity chemicals and implement wastewater treatment. The effects of various culture medium compositions on Chlorella vulgaris growth and lipid production were investigated using batch culture. Thirteen culture media: Modified Chu’s No. 10, Bold basal, BG-11, Modified BG-11, N-8, M-8, RM, Modified Spirulina, F-si, Fogg’s Nitrogen free, Fog, F/2, and Johnson medium were compared in terms of optical density, biomass production, specific growth rate and lipid production. Following a 10-day culture in a temperature controlled environment, Bold basal medium was found to have the highest average biomass productivity of 48.056 ± 2.097 mg L -1 day -1 , with overall specific growth rate of (d -1 ): 0.211 ± 0.003 and lipid productivity of 9.295 mg L -1 day -1 among the selected media. This is a basis for the optimization of different cultivating medium to enhance algal lipid production. In order to maximize the quality and quantity of the algal biomass and lipid content in Chlorella vulgaris, different strategies were used using different ratios of nitrogen and phosphorus source in the modified Bold basal medium (BBM). In the 12-day batch culture period, the highest biomass productivity obtained was 72.083 mg L -1 day -1 under Bold basal medium with Nitrogem control Phosphorus limited conditions. The highest lipid content, lipid concentration and lipid productivity obtained were 53.202%, 287.291 mg/L and 23.449 mg L -1 day -1 respectively, under Bold basal medium with Nitrogen Control Phosphorus Deprivation conditions. Nitrogen starvation was found to be the critical factor affecting the biomass production and lipid accumulation while the starvation of phosphorus induced a higher total lipid content and affected the lipid composition of Chlorella vulgaris cultures. Recently, as the demand for pure microalgae strains for the production of algal lipid as a feedstock of renewable energy has been increasing, the designation of an effective photobioreactor (PBR) for mass cultivation is essential to assure stability in the amount of feedstock. Various PBRs design such as bubbling, air-lift, porous air-lift was compared. In general, the bubbling design is a better PBR designs than the others, having the highest biomass concentration of 0.78 g/L during the culture time. Besides, it was observed that the 35 cm draft tube of the porous air-lift PBR had shorter mixing time (24.5 seconds) and higher biomass concentration (0.518 g/L) than the 50 cm air- lift design. The bubbling PBR with the highest gas flowrate of 2.7 L/min produced the highest biomass production of 0.74 g/L within the cultivation time. The information is shown to be a useful guide for determining the optimal condition of the PBRs. Light wavelengths and intensities were determinant factors in affecting the growth and lipid content of autotrophic organisms such as C. vulgaris. The experiment investigated the effect of algal lipid production by using LEDs (Light Emitting Diodes) with different wavelengths. C. vulgaris was grown in the effluent for 10 days under the photoperiod of 18:6 h Light/Dark cycles with different visible light sources (cool white, blue and red) and intensities (50 μmol m -2 s -1 ) at 25°C. The overall maximum dry biomass of 1353.33 mg/L was observed at 50 μmol m -2 s -1 cool white light during 10th culture day, with the highest overall productivity of dry biomass production (117.23 mg/L d -1 ) within cultivation time. The highest lipid content (34.06 %) was obtained with the blue color due to light efficiency and deep penetration to the photosynthetic pigments (chlorophyll) in C. vulgaris. However, the highest lipid productivity was observed in cool white light of 318.63 mg/L during the 10th culture day. The effect of light intensity toward the lipid productivity was further investigated by increasing the light intensity of cool white light. The highest lipid productivity was observed at 110 μmol m -2 s -1 in a light intensity of 658.99 mg/L during the 10th culture day. In high irradiance (110 μmol m -2 s -1 ), the proportion of poly unsaturated fatty acid (C18:1 and C18:2) contributed most of the fatty acid methyl ester (FAME) content in the collected sample, irrespective of all treatments. The next study optimized the harvesting rate of algae by using an electro- coagulation-flotation (ECF) harvester, which combines the electrochemical reaction in the electrodes and the dispersion of hydrogen gas to allow floatation of microalgae cell for surface harvesting. The response surface methodology model (RSM) was employed to optimize different ECF parameters: electrode plate material, electrode plate number, charge of electrode, electrolyte concentration and pH of the solution. The model revealed that aluminum was the best electrode material for the ECF process. It was also found that a three electrode plates setup with one anode and two cathodes had the best performance for harvesting. Additionally, sodium chloride (NaCl) at 8 g/L in harvesting medium could increase the flocculant concentration and reduce electric power consumption. Also, having the culture medium at pH 4 also had a significant effect on improving the flocculant production. Combining these optimal conditions, the highest flocculant concentration reached 2966 mg/L in 60 mins; a 79.8% increase in flocculant concentration, based on the tested conditions. The results of this study show the significance of different parameters affecting the coagulation and flocculation of C. vulgaris and provide a reference for the design of a large-scaled harvester for microalgae harvesting in the further study. To conclude, this research comprises a study on the use of indigenous algae for the production of algal lipid, which is used to produce commodity chemicals. Details on the use of nutrient sources, the techniques of cultivation and the optimization of cell harvesting were included so as to remove nutrients from effluents to minimize the occurrence of eutrophication in harbor, thereby providing economic advantages. Thus, the optimization of these processes is very adequate and offers significant advantages for the wastewater treatment. The developing of algal cell biotechnology is necessary to further enhance algal lipid production in an attempt to apply it commercially.

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Dantas, Denise Conceição Mesquita. "Efeitos da Chlorella vulgaris sobre a resposta imunologica de camundongos infectados com a Listeria monocytogenes." [s.n.], 1999. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314564.

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Orientador: Mary Luci de Souza Queiroz
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Neste trabalho estudamos os efeitos imunofarmacológicos do extrato da Chlorella vulgaris (ECV), sobre a resposta imunológica de camundongos BALB/c _infectados com a bactéria Usteria monocytogenes. . O efeito do ECV foi verificado sobre o número de células progenitoras hematopoiéticas da medula óssea para a série granulócito-macrófago (CFU-GM) e sobre a atividade estimuladora de colônia (CSA), presente no soro de animais infectados com a L. monocytogenes, tratados com o ECV e tratados e infectados. Além disso, investigamos nestes animais os efeitos do ECV sobre a atividade de células "Natural Killer" (NK) e sobre a resposta específica 'a infecção através das citocinas produzidas pelas sub-populações de células T auxiliares "T helper-1" (Th1) através dos níveis de interleucina-2 (IL-2) e interferon-gama (IFN-y), e de "Thelper-2"(Th2) pelos níveis de interleucina-4 (IL-4) e interleucina-10 (IL-10). Para a realização dos experimentos os animais foram tratados por via oral durante cinco dias consecutivos com o ECV na dose de 50 mg/Kg/dia. Ao final do tratamento, os animais foram infectados com uma dose sub-letal da bactéria (1x104 bactérias/animal). Os animais inoculados com a bactéria apresentaram uma mielosupressão que foi revertida pelo tratamento prévio com o ECV, observada nos animais tratados e infectados em relação àqueles somente infectados. Essa mesma relação também foi verificada quanto a atividade estimuladora de colônia (CSA), investigada no soro destes animais, nas 48 e 72 horas após a infecção. Com relação a atividade de células NK, o ECV produziu uma estimulação dessas .células mesmo em animais controle (sem infecção), promovendo um aumento mais pronunciado, na vigência da infecção; entretanto, quando os animais foram previamente tratados com o ECV e infectados um aumento adicional pôde ser detectado. o ECV também demonstrou ter um efeito estimulador sobre a produção de citocinas. Nossos resultados apresentaram um aumento da IL-2 em animais tratados com o ECV e infectados em relação aos controles. Em resposta à infecção, todos os grupos demonstraram um aumento de IFN-y que, entretanto, observou-se serem mais elevados nos animais que receberam tratamento prévio com o ECV e foram infectados, do que em animais apenas inoculados com a bactéria. Porém, o aumento significativo de IFN-y foi detectado 72 horas após a infecção, comparado ao respectivo grupo somente infectado. Das citocinas produzidas por Th2 (IL-4 e IL-1 O) e em relação ao grupo controle, a L-4 apresentou um ligeiro aumento, verificado apenas no grupo tratado e infectado (48h), contrariamente à IL-10 que não apresentou níveis alterados em grupo algum. Para avaliar a resistência dos animais à infecção, realizamos uma curva de sobrevida utilizando uma dose letal da L. monocytogenes (3x105 bactérias/animal), e duas doses do ECV, 50 e 500 mg/Kg/dia durante cinco dias de tratamento prévio à infecção. A dose de 50 mg/Kg protegeu 20% dos animais infectados e a de 500 mg/Kg do ECV conferiu a estes animais uma sobrevida de 52%, quando comparados aos animais controle, apenas infectados, onde a mortalidade foi de 100%. Diante dos resultados obtidos neste trabalho, podemos sugerir que o ECV aumenta a resistência dos camundongos BALB/c infectados com a L. monocytogenes .Através da modulação da resposta imunológica inespecífica verificada pelo aumento dos precursores hematopoiéticos da medula óssea, da atividade de células NK; como também pelo aumento da resposta Th1, através dos níveis de IFN-y e IL-2 que se sobrepôs sobre a resposta Th2
Abstract: In the present study, we have investigated the effects of the Ch/orella vu/garis extract (CVE) on the growth and differentiation of bone marrow hematopoietic cells (CFU-GM), and on serum colony stimulating activity (CSA) in normal and Usteria monocytogenes infected mice. We have also investigated the effects of the CVE on Natural Killer cells and on Th1 cells activity (by IL-2 and IFN-y production) and Th2 activity (by IL-4 and IL-10) in normal and infected mice.Mice were pre-treated with dive doses of CVE (50 mg/Kg/day) and then infected with a sub lethal dose (1x104 bacterialanimal) of L monocytogenes. The treated mice showed an increased number of CFU-GM in the bone marrow and increased serum colony stimulating activity, at 48 and 72 hours after the infection, when compared to the infected mice. In relation to the NK cells activity, the CVE produced a significant increase in normal (non-infected) animals compared to the controls. Similarly, the infection alone praduced a signiticant increase on NK activity at 48 and 72 hours after the infection. When the animais were pre-treated with CVE and infected, an additional increase on the NK activity was observed. Regarding the cytokines production, in the treated and infected animals there was an increase on IL-2 and IFN-y compared to the contrails. However, the IFN-y showed an increase in the treated and infected group in relation to the infected group at 72 hours after the inoculation of the bacteria. The Th2 activity was not significant. Just the IL-4 showed an increase in the treated and infected group (48h) compared to the control group. The CVE treatment (50 and 500 mg/Kg) of mice infected with a dose of 3x105 bacterialanimal, which was lethal for all the non-treated contrails, has produced a dose response protection which led to a 20% and 52% survival, respectively
Doutorado
Fisiologia
Doutor em Ciências Biológicas

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42

Attalah, Said. "Energy evaluation of the High Velocity Algae Raceway Integrated Design (ARID-HV)." Thesis, The University of Arizona, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1536266.

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The original ARID (Algae Raceway Integrated Design) raceway was an effective method to increase temperature toward the optimal growth range. However, the energy input was high and flow mixing was poor. Thus, the ARID-HV (High Velocity Algae Raceway Integrated Design) raceway was developed to reduce energy input requirements and improve flow mixing. This was accomplished by improving pumping efficiency and using a serpentine flow pattern in which the water flows through channels instead of over barriers. A prototype ARID-HV system was installed in Tucson, Arizona, and the constructability, reliability of components, drainage of channels, and flow and energy requirements of the ARID-HV raceway were evaluated. Each of the electrical energy inputs to the raceway (air sparger, air tube blower, canal lift pump, and channel recirculation pump) was quantified, some by direct measurement and others by simulation. An algae growth model was used to determine the algae production rate vs. flow depth and time of year. Then the electrical energy requirement of the most effective flow depth was calculated. Channel hydraulics was evaluated with Manning's equation and the corner head loss equation. In this way, the maximum length of channels for several raceway slopes and mixing velocities were determined. Algae production in the ARID-HV raceway was simulated with a temperature and light growth model. An energy efficient design for the ARID-HV raceway was developed.

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43

Archbold, Brad. "Using algae to capture CO₂ and as a feedstock for biofuel." Online pdf file accessible through the World Wide Web, 2007. http://archives.evergreen.edu/masterstheses/Accession86-10MES/Archbold_%20B%20MESThesis%202007.pdf.

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Yang, Ying. "Effects of Temperature, Light Intensity and Quality, Carbon Dioxide, and Culture Medium Nutrients on Growth and Lipid Production of Ettlia oleoabundans." Digital WPI, 2014. https://digitalcommons.wpi.edu/etd-dissertations/42.

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Ettlia oleoabundans, a freshwater green microalga, was grown under different environmental conditions to study its growth, lipid yield and quality for a better understanding of the fundamental physiology of this oleaginous species. E. oleoabundans showed steady increase in biomass under low temperature and low light intensity, and at high temperature lipid cell content significantly increased independent of nitrate depletion. Studies on light quality showed that red light treatment did not change the biomass concentration, but stimulated lipid yield especially oleic acid, the most desirable biodiesel precursor. Moreover, no photoreversibility in lipid production was observed when applying alternating short-term red and far-red lights, which left the phytochrome effect still an open question. In addition, carbon dioxide enrichment via an air sparging system significantly boosted exponential growth and increased carbon conversion efficiency. Finally, a practical study demonstrated the feasibility of growing E. oleoabundans for high lipid production using a diluted agricultural anaerobic waste effluent as the medium. Together, these studies showed the potential of E. oleoabundans as a promising high yield feedstock for the production of high quality biodiesel.

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Winckelmann, Dominik [Verfasser], Mathias [Akademischer Betreuer] Winterhalter, Roland [Akademischer Betreuer] Benz, and Gerd [Akademischer Betreuer] Klöck. "Development of a management system for large scale algae cultures / Dominik Winckelmann. Betreuer: Mathias Winterhalter. Gutachter: Mathias Winterhalter ; Roland Benz ; Gerd Klöck." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2015. http://d-nb.info/1087274788/34.

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46

Power, Sean Duncan. "The water and nutrient potential of brewery effluent for hydroponic tomato production." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1011604.

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Brewery effluent that had undergone treatment in an anaerobic digester (AD) was used as an alternative water and nutrient source for hydroponic crop production. Brewery effluent was demonstrated to contain sufficient nutrients to support the growth, flowering and fruiting of Lycopersicum escolentum "Moneymaker" tomato crops. The adjustment of the effluent pH with phosphoric acid to between pH 6.0 and 6.5 increased the development of the crops by around 100% compared to crops grown in unaltered effluent. The pH adjusted effluent-grown plants grew to a mean height of 831.4 ± 21.1 mm and a dry biomass weight of 42.34 ± 2.76 g compared to the unaltered pH effluent plants which grew to a height of 410.6 ± 20.5 mm and a weight of 7.65 ± 0.68 g after 49 days. Effluent treatment in high-rate algal ponds (HRAP) was determined to have no positive effect on the nutritional potential of the effluent for Moneymaker production. The effluent-grown plants did not perform as well as plants grown in inorganic-fertilizer and municipal water. Plants grown in effluent grew taller but did not produce significantly more fruit when phosphoric acid (height: 1573.3 ± 50.4 mm, 19.4 ± 1.4 fruit per plant) was compared to nitric acid (height: 1254.1 ± 25.4 mm, 15.6 ± 1.5 fruit per plant) as the pH adjustment over 72 days. Direct and secondary plant stresses from effluent alkalinity, ammonium nutrition, nitrogen limitation, sodium concentrations and heat stress among other factors were probably confounding variables in these trials and require further investigation. Considering the raw effluent composition and manipulating the AD operation is a potential opportunity to improve overall AD performance, reduce chemical inputs in the effluent treatment process, reduce the final effluent alkalinity, and increase available nitrogen content in the final effluent. The anaerobic digester discharging >1000 m³ of nutrient enriched effluent every day is a resource with considerable potential. The benefits of developing this resource can contribute to cost-reduction at the brewery, more efficient water, nutrient and energy management at the brewery, and offer opportunities for job creation and potentially benefit local food security.

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47

Pereira, Alitiene Moura Lemos. "Cultura em larga escala da microalga Ankistrodesmus gracilis (Reinsch) Korsikov (Chlorophyceae), e do microcustáceo Diaphanosoma birgei (Korineck, 1981) (Cladocera) em laboratório /." Jaboticabal, 2001. http://hdl.handle.net/11449/144169.

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Orientador: Lúcia Helena Sipaúba Tavares
Banca: Odete Rocha
Banca: Maria da Graça Gama Melão
Banca: José Sávio Colares de Melo
Banca: José Augusto Senhorini
Resumo: O objetivo deste trabalho foi analisar a viabilidade da cultura em larga escala e a composição bioquímica da alga Chlorophyceae Ankistrodesmus gracilis e do Cladocera Diaphanosoma birgei em laboratório. O experimento foi realizado no Laboratório de Limnologia e Produção de Plâncton do Centro de Aqüicultura da UNESP (CAUNESP). As algas foram cultivadas em meio Chu12 e NPK (20:5:20), sob iluminação contínua (4.000 e 1.100 lux para pequena e larga escala, respectivamente), aeração constante e temperatura controlada (24,0±2,0ºC). O tempo de produção das algas foi de 31 dias, concentração na fase exponencial variando de 68,50 a 358,38 x 104 células.ml-1 nos diferentes volumes de cultivo. A análise bioquímica revelou que a alga apresenta 32,6% de proteína, 20,0% de carboidrato, 8,0% de extrato etéreo, 18,3% de cinzas, 3,2% de fibras e 4.583 cal/g. O aminograma revelou que 58,7% da proteína era constituída por aminoácidos essenciais. A relação Ca:P foi aproximadamente 1:1. O Cladocera foi oriundo dos viveiros de piscicultura do CAUNESP, isolado e criado em volumes de 500ml a 850L, em sistema estático, alimentados com A. gracilis, em temperatura de 23,3±3,6ºC, fotoperíodo natural e aeração suave. O tempo de produção do Cladocera foi de 27 dias com densidade final de 2.500 indivíduos.L-1. A análise bioquímica deste microcrustáceo revelou uma composição de 70,0% de proteína, 5,7% de carboidrato, 8,7% de extrato etéreo, 11,5% de cinzas, 4,3% de fibras e 4.627 cal/g. Os resultados apresentados sugerem que Ankistrodesmus gracilis e Diaphanosoma birgei são espécies com potencial para cultura e alimentação na aqüicultura
Abstract: The objective of this work was to analyze in detail the viability of the culture and the biochemical composition of the Chlorophyceae algae Ankistrodesmus gracilis and of the Cladocera Diaphanosoma birgei in laboratory. The experiment was carried out in the Limnology Laboratory and Plankton Production in the São Paulo State Aquaculture Center at UNESP (CAUNESP). The algae were cultivated using a culture media of Chu12 and NPK (20:5:20), under continuous light (4000 and 1100 lux for massive and small scale, respectively), constant aeration and controlled temperature (24.0±2.0ºC). Algae production time was of 31 days, concentration during the exponential phase varied from 68.5 to 358.38 x 104 cells.ml-1 in different volumes of culture. Biochemical analyses revealed that the algae presents 32.6% of protein, 20.0% of carbohydrate, 8.0% ethereal extract, 18.3% of ashes, 3.2% of fibers and 4.583 cal/g. The aminogram revealed that 58.7% of the protein was made up of essential aminoacids. The Ca:P relation was of approximately 1:1. The cladoceran was derived from the CAUNESP fish culture ponds, isolated and produced in volumes of 500ml to 850L, in batch system, fed with A. gracilis, at temperatures of 23.3±3.6ºC, natural photoperiod and mild airing. Cladocera production time was of 27 days with final density of 2500 individuals.L-1. The biochemical analyses of this micro-crustacean revealed a composition of 70.0% of protein, 5.7% of carbohydrate, 8.7% of ethereal extract, 11.5% of ashes, 4.3% of fibers and 4627 cal/g. The results here presented suggest that Ankistrodesmus gracilis and Diaphanosoma birgei are species with potential for culture and feeding in aquaculture
Doutor

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48

Wang, Zhaowei. "Two Approaches for Cell Retention in Perfusion Culture Systems." Cleveland State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=csu1274106674.

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49

Hayden, Jason. "A multi-species mariculturesystem : a holistic approach to ornamental culture." Thesis, Cape Peninsula University of Technology, 2010. http://hdl.handle.net/20.500.11838/2034.

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Thesis (MTech (Oceanography))--Cape Peninsula University of Technology, 2010
Coral reefs are in a worldwide state of crisis due to overexploitation. One of the factors contributing to the over exploitation is the marine ornamental industry. This industry utilises a diversity of organisms, comprising approximately 1470 species of fish and more than 300 species of invertebrates. Between April and December 2007, five of the 18 companies who had import permits for South Africa, imported a total of 359 different ornamental species, 252 of these were fish species while the remaining 107 species were invertebrates. During these nine months a total of 32 005 individual organisms were imported into South Africa by the five companies. There were two groups of fish that represented the highest import volumes. These were Amphiprion spp. and Pomacentradae spp., as well as the Gobidae spp. These groups represented 38% and 19% respectively of the total number of fish imported" Aquaculture has the potential to substantially reduce the harvesting pressure on coral reef organisms globally. A small-scale multi-species mariculture system was designed and constructed for benthic egg-laying species of fish (brood stock), corals, and ornamental algae. The system was designed to be low cost and easy to operate. The total capital costs for the system was R15 680.70. In order to estimate the potential yield of an aquaculture facility it is important to know the growth rate of the proposed species under pilot conditions. The use of artificial lighting regimes in aquaculture comes at a financial cost. It is for this reason that it is important to know what lighting scenario yields the highest growth rate of corals. The effects of photoperiod were tested on Sinularia sp. of coral. Two photoperiods were tested, namely: Groups (8:16 h Iight:dark cycle) and Group12 (12:12 h light:dark cycle). No significant difference in weight was found between Group8 and Group12 (p = 0.975). There was however a significant increase (p = 0.002) in Surface-area Pixel Value (SPV) for Groups (1996.73 millipixels pixel-1 day -1) compared to Group12 (983.73 millipixels pixel-1 day -1). The use of a 8:16 h lightdark cycle can thus yield coral of a larger size but not necessarily a higher mass.

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Thuillier-Bruston, Francine. "Culture photoorganotrophique sur milieu glycolate et metabolisme photorespiratoire de ce substrat chez euglena gracilis z." Paris 7, 1987. http://www.theses.fr/1987PA077086.

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Les euglenes cultivees en presence du substrat glycolate utilisent le systeme chloroplastique pour synthetiser leurs reserves carbonees et s'apparentent aux euglenes photoautotrophes par leur photochimie du psii, leurs activites carboxylasiques et leur ultrastructure

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Dissertations / Theses on the topic 'Algal Cultures'

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