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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Caracterização espectroscópica e ensaios químico - biólogicos de H2(TNBPyP) e Zn(TPPS4) visando utilização em terapia fotodinâmica

Silva, Jeanine Domareski da 18 December 2009 (has links)
Made available in DSpace on 2017-07-24T19:38:01Z (GMT). No. of bitstreams: 1 Jeanine Domareski da Silva.pdf: 2050908 bytes, checksum: a3e1a7fc30e3328ab9f1c0aef96b7ea4 (MD5) Previous issue date: 2010-12-18 / The investigation of properties of porphyrin derivatives is of great importance, since they have many applications, one being the use as photo sensitizers in photodynamic therapy (PDT). We studied the free base porphyrin, cationic, bromide of 5, 10, 15, 20 - tetrakis (N-4-nitrobenzyl-4-pyridyl) porphyrin, H₂(TNBPyP) and metaporphyrin, sodium salt of 5, 10, 15, 20 - tetrakis (4-sulfonatophenyl) zinc porphyrin (II), Zn(TPPS₄), to evaluate the possible application in PDT. Through analysis of molecular absorption UV-Vis, we investigated the interaction with surfactants, the reactions of photo bleaching, the generation of singlet oxygen and the ability to aggregate in different proportions water/ethanol. The photodynamic action of these compounds was analyzed by in vitro tests with microorganisms; tests were carried out with Arthemia saline and the Staphylococcus aureus. The System used was of LEDs of different emission bands (red, orange and green) for illumination of the samples in the tests for the evaluation of the photodynamic action. First, we analyzed the spectral behavior of porphyrin H₂(TNBPyP), with the variation of pH in water and ethyl acetate/phosphate and in the presence of surfactant HPS (Zwitterionic), SDS (anionic) and CTAB (cationic). It was observed that porphyrin is stable in a wide range of pH in the various systems studied. The spectral behavior of porphyrin mixtures H₂(TNBPyP) in water/ethanol in different proportions indicated that there was no clustering in the concentration range examined. Analysis of photo bleaching was performed for the two porphyrins in light of LED systems for the total of 1 hour; it was observed that both porphyrins are photo-stable under the conditions studied. As the generation of singlet oxygen, observed through the test of uric acid, it was found that the H₂(TNBPyP) showed a higher photodynamic activity (PA) than Zn(TPPS₄). The results of microbiological tests showed that the highest mortality rate of A. saline occurs in the presence of porphyrin H₂(TNBPyP) and under illumination with red LED, indicating photodynamic action of porphyrin. In tests with the bacterium Staphylococcus aureus, we observed the effects of photodynamic action for the two porphyrins examined and the two types of LEDs tested, and the best results were obtained by photo inactivation under lighting time of 30 minutes. Thus, the results show that the porphyrins tested have potential for the use in Photodynamic Therapy. / A investigação de propriedades de porfirinas e derivados é de grande importância, visto que estes possuem inúmeras aplicações, sendo uma delas o uso como fotossensibilizadores em Terapia Fotodinâmica (TFD). Neste trabalho estudou-se a porfirina base livre, catiônica, brometo de 5, 10, 15, 20 – tetrakis (N-4-nitrobenzil-4- piridil) porfirina, H2(TNBPyP), e a metaloporfirina, sal de sódio de 5, 10, 15, 20 – tetrakis (4-sulfonatofenil) porfirina zinco(II), Zn(TPPS4), para de avaliar a possível aplicação em TFD. Através da análise da absorção molecular UV-Vis, foram investigadas a interação com surfactantes, as reações de fotobranqueamento, a geração de oxigênio singlete e a capacidade de agregação em diferentes proporções água/etanol. A ação fotodinâmcia dos compostos estudados foi analisada através de ensaios in vitro com microorganismos, foram realizados testes com Artemia salina e com a bactéria Staphylococcus aureus. Foi utilizado sistema de LEDs de diferentes faixas de emissão (vermelho, laranja e verde) para iluminação das amostras nos testes para avaliação da ação fotodinâmica. Primeiramente, analisou-se o comportamento espectral da porfirina H2(TNBPyP), com a variação do pH em meio aquoso e em acetato/fosfato e na presença dos surfactantes HPS (zwiteriônico), SDS (aniônico) e CTAB (catiônico). Observou-se que a porfirina é estável numa ampla faixa de pH nos vários sistemas estudados. O comportamento espectral da porfirina H2(TNBPyP) em misturas água/etanol de diferentes proporções indicou que não houve a formação de agregados na faixa de concentração analisada. A análise de fotobranqueamento foi realizada para as duas porfirinas sob iluminação de sistemas de LEDs durante um período total de 1 hora, foi observado que ambas as porfirinas são foto-estáveis nas condições analisadas. Quanto a geração de oxigênio singlete, observada através do teste do ácido úrico, verificou-se que a H2(TNBPyP) apresentou maior atividade fotodinâmica (AF) que a Zn(TPPS4). Os resultados dos testes microbiológicos mostraram que o maior índice de mortalidade sobre A. salina ocorre na presença da porfirina H2(TNBPyP) e sob iluminação com LED vermelho, indicando ação fotodinâmica da porfirina. Nos testes com a bactéria Staphylococcus aureus, observou-se ação fotodinâmica para as duas porfirinas analisadas e com os dois tipos de LEDs testados, sendo que os melhores resultados de fotoinativação foram obtidos para o tempo de iluminação de 30 min. Assim, os resultados demonstram que as porfirinas testadas tem potencial para serem utilizadas em Terapia Fotodinâmica.
72

Determinación del efecto antidiarreico en ratones albinos del extracto etanólico de hojas de Solanum radicans L.F “ñuchco hembra” y evaluación de citotoxicidad en Artemia salina

Malpartida Cóndor, Saul January 2018 (has links)
Determina el efecto antidiarreico del extracto etanólico de hojas de Solanum radicans L.F “ñuchco hembra” en ratones machos albinos por vía oral, donde se utilizó el modelo de inducción de diarrea con aceite ricino (10 mL/Kg) divididos en los siguientes grupos: suero fisiológico 10 mL/Kg, fármaco estándar Loperamida 2 mg/kg y extracto etanólico de hojas de Solanum radicans L.F a las concentraciones de 400, 600 y 900 mg/kg. Se administró a cada animal 0,2 mL de suspensión de carbón activado (10%) en goma tragacanto (1%) como marcador del desplazamiento en el intestino; y finalmente fueron eutanizados por dislocamiento cervical. La cavidad abdominal fue abierta para determinar la longitud total del intestino delgado de cada animal (píloro hasta la válvula ileocecal), así como el desplazamiento del carbón activado, donde se calculó el porcentaje de disminución del movimiento peristáltico de la Loperamida y Solanum radicans L.F. Los resultados muestran un mayor efecto antidiarreico a dosis de 400 mg/Kg (p<0,05) con 69,66% de disminución del movimiento peristáltico, comparado con el fármaco estándar que presentó 63,42%. Se realizó tamizaje fitoquímico preliminar del extracto etanólico de hojas de Solanum radicans L.F detectándose en mayor cantidad la presencia de alcaloides, flavonoides, azúcares, esteroides; además se realizó la cromatografía en capa fina (CCF) del extracto etanólico de hojas de Solanum radicans L.F comparándolos con estándares de atropina, rutina y quercetina. Se evaluó la citotoxicidad frente a Artemia salina, del extracto etanólico de hojas de Solanum radicans L.F para lo cual se preparó solución madre de 1000 ug/mL (10 mg del extracto seco en 10 mL de agua de mar artificial) y a partir de ahí se emplearon concentraciones de 5, 10, 15, 20, 25 y 30 ug/mL, donde se obtuvo el valor de la concentración letal media de 12,83 ug/mL. Se concluye que el extracto etanólico de hojas de Solanum radicans L.F tiene efecto antidiarreico y una actividad citotóxica en los modelos experimentales trabajados. / Tesis
73

Viabilidade do uso de Artemia franciscana (Kellogg, 1906) de Grossos-RN, Brasil, no cultivo de Litopenaeus vannamei (Boone, 1931) em tanques-berçário

SILVA, Adriano Prysthon da 06 November 2003 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-06T16:26:22Z No. of bitstreams: 1 Adriano Prysthon da Silva.pdf: 1164942 bytes, checksum: 8a3eb14fef1483fd2fc15c7afca6f216 (MD5) / Made available in DSpace on 2017-02-06T16:26:22Z (GMT). No. of bitstreams: 1 Adriano Prysthon da Silva.pdf: 1164942 bytes, checksum: 8a3eb14fef1483fd2fc15c7afca6f216 (MD5) Previous issue date: 2003-11-06 / The Método de Alimentação Comercial (MAC) and the Método de Alimentação Artemia (MAA) were evaluated, aiming to maximize the growth and survival rate of the Litopenaeus vannamei post-larvae, reducing the feeding cost/benefity, in the post-larvae culture in nursery tanks. The experiment took place at the Tabatinga Aquacultura Ltda farm, in february 2003, using nursery tanks of 60m3, where the post-larvae (Pl19) were stocked at 16Pl’s/L. The end of ten days of culture, the weith-length relationship and time, that MAA fed post-larvae had heavier a significant growth (in weigth) (P<0,05) than those treated with MAC. The models could had been written in the following form: W(g) = (0,0069MAC + 0,0094MAA).L(cm)2,9094 (R2= 99,33%); W(g)=e0,1739T(dias)-5,4083MAC-5,1609MAA (R2=99,71%). The post-larvae survival treated with MAA(86,25%), was higher than (P≤0,05) other method (62,12%). The physical, chemical and biological parameters of water of the tank, where the MAA was administrated, were always smaller than MAC and consequently induced a lower daily increase rate. We could conclude that the growth and survival rates of the post-larvae of L. vannamei results were better when Artemia franciscana nauplii were used in nursery tanks. They represented a significant reduction (P<0,01) polluting levels. Economicaly, the artemia was viable in when compared to artificial food. / Foram avaliados o Método de Alimentação Comercial (MAC) e o Método de Alimentação Artemia (MAA), objetivando maximizar a taxa de crescimento e sobrevivência das pós-larvas do camarão marinho Litopenaeus vannamei, reduzir os níveis de poluentes dos efluentes do berçário e, estabelecer uma relação custo/benefício da alimentação, na fase de cultivo das pós-larvas nos tanques-berçário. O experimento foi realizado na carcinicultura Tabatinga Aquacultura Ltda, em fevereiro de 2003, utilizando-se tanques berçário de 60 m3, em que as pós-larvas (Pl19) foram estocadas em densidades de 16 Pl’s/L. Ao final de 10 dias de cultivo, verificou-se com base nas relações do peso em função do comprimento e do tempo, que as pós-larvas alimentadas com MAA apresentaram maior ganho de peso (P<0,05) do que as que receberam o MAC. Os modelos matemáticos para o peso em função do comprimento e do tempo podem ser escritos da seguinte forma: W(g) = (0,0069MAC +0,0094MAA).L(cm)2,9094 (R2= 99,33%); W(g)=e0,1739T(dias)-5,4083MAC-5,1609MAA (R2=99,71%). A sobrevivência das pós-larvas provenientes do MAA (86,25%) foi superior (P≤0,05) ao MAC (62,12%). As concentrações das variáveis físicas, químicas e biológicas da água do tanque-berçário que foi ministrado o MAA, foram menores e conseqüentemente induziram menor taxa de incremento diário do que o MAC. Pôde-se concluir que as taxas de crescimento e sobrevivência das pós-larvas de L. vannamei foram maiores quando se utilizou náuplios de Artemia franciscana como alimento nos tanques-berçário, além de ser registrada uma redução extremamente significativa (P<0,01) dos níveis de nutrientes responsáveis pela eutroficação e conseqüente poluição. Em termos de quantidade de alimento, a A. franciscana foi viável economicamente em relação ao alimento artificial.
74

Controle bacteriano na eclosão e enriquecimento de Artemia sp. para sua aplicação na alimentação de pós-larvas de Litopenaeus vannamei

INTERAMINENSE, Juliana Rangel de Aguiar 28 February 2012 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-15T13:16:21Z No. of bitstreams: 1 Juliana Rangel de Aguiar Interaminense.pdf: 435666 bytes, checksum: fc8f9ada1887395801298c79901d84cc (MD5) / Made available in DSpace on 2017-02-15T13:16:21Z (GMT). No. of bitstreams: 1 Juliana Rangel de Aguiar Interaminense.pdf: 435666 bytes, checksum: fc8f9ada1887395801298c79901d84cc (MD5) Previous issue date: 2012-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study aimed to evaluate the antibacterial effects of different supplements on Artemia sp. hatching and enrichment. The supplements were added to the water used for Artemia hatching of capsulated and decapsulated cysts and for Artemia enrichment water. The experiment consisted in the addition of the diatom Chaetoceros calcitrans, a commercial probiotic (Bacillus spp.), antimicrobial Florfenicol to the hatching water and control without supplements. The enrichment experiment was performed by the application of C. calcitrans, probiotic and commercial emulsion DHA / EPA rich to enrichment water and control constituted by newly hatched nauplii. The enriched Artemia were offered for the PL7 to PL19 of Litopenaeus vannamei stages. The Vibrio spp. load of hatching water and newly hatched nauplii were quantified at the end of hatching. The Vibrio spp. quantification of postlarvae, enriched Artemia and water of enrichment and postlarvae rearing was also performed. The Vibrio presumptive colonies isolated from newly hatched nauplii were identified. Furthermore, Vibrio spp. present in nauplii subjected to freezing and Bacillus spp. colonies of Artemia and postlarvae of Probiotic treatment were quantified. Assessing the overall results of the study, the decapsulation process did not shown to be effective in reducing the Vibrio spp load of nauplii and water in all treatments. The C. calcitrans addition in Artemia hatching water has proven to be an effective alternative to antibiotic use. The probiotic use must also be considered to control Vibrio spp. load in Artemia nauplii. However, the supplements use to Artemia enrichment process may promote a bacterial increase and other procedures for its control must be evaluated. / O presente trabalho teve por princípio avaliar os efeitos antibacterianos de diferentes suplementos na eclosão e no enriquecimento de Artemia sp. Os suplementos foram adicionados na água utilizada para eclosão de cistos de Artemia capsulados e descapsulados e à água de enriquecimento de metanáuplios de Artemia. O experimento de eclosão consistiu no acréscimo da diatomácea Chaetoceros calcitrans, de probiótico comercial (Bacillus spp.), do antimicrobiano Florfenicol e controle sem adição de agentes. O experimento de enriquecimento foi realizado pela aplicação de C. calcitrans, de probiótico comercial e de emulsão comercial rica em DHA/EPA à água de cultivo de metanáuplios e controle constituído por náuplios recém eclodidos. Os metanáuplios foram oferecidos para os estágios de PL7 a PL19 de Litopenaeus vannamei. A carga de Vibrio spp. da água de eclosão e náuplios recém eclodidos foram quantificadas no final do período de eclosão. A quantificação de Vibrio spp de pós larvas, metanáuplios, água de cultivo das pós larvas e enriquecimento de Artemia também foi realizada. As colônias presuntivas de Vibrio oriundas de náuplios recém eclodidos foram identificadas. Além disso, Vibrio spp. presente em náuplios submetidos ao congelamento e colônias de Bacillus spp. em amostras de Artemia enriquecida e pós-larvas do tratamento Probiótico foram quantificadas. Avaliando dos resultados gerais do estudo, o processo de descapsulação não demonstrou ser eficiente na redução da carga de Vibrio spp. nos náuplios e na água de todos os tratamentos. A adição de C. calcitrans na água de eclosão de Artemia provou ser uma alternativa eficaz para em alternativa a utilização de antibióticos. A utilização de probiótico deve ser também considerado para controlar a carga de Vibrio spp em náuplios de Artemia. No entanto, a utilização de suplementos para o processo de enriquecimento de Artemia pode favorecer o aumento da carga bacteriana e outros procedimentos para o seu controle deve ser avaliada.
75

Remoção de corantes têxteis em efluentes simulados por coagulação e avaliação de toxicidade /

Mauro, Artur Blikstad. January 2016 (has links)
Orientador: Ederio Dino Bidoia / Banca: Carlos Renato Corso / Banca: Peterson Bueno de Moraes / Resumo: A escassez de água potável está sempre em foco por ser um pré-requisito para a vida. Nas grandes cidades é evidente como uma preocupação que determina a vida de bilhões de cidadãos, sendo um recurso que movimenta a economia e a saúde pública. É fundamental nas indústrias movimentando a economia, e muitas vezes ao sair delas, como efluente, não é submetida aos tratamentos necessários antes de ser devolvida aos cursos hídricos, dos quais primeiramente foi retirada. Este trabalho visa aprimorar os métodos de remoção de corante Acid Red 114 e Acid Blue 40 do efluente de indústrias têxteis com o uso do processo de coagulação e floculação. Uma vez que os efluentes não tratados geram problemas ecológicos, com um grande impacto ambiental, seu tratamento é fundamental para evitar a contaminação de nossos mananciais. O método escolhido de tratamento foi o de coagulação/floculação por ser amplamente empregado em ETE (Estações de Tratamento de Efluentes) e possuir uma boa eficiência e baixo custo. Com o uso da espectrofotometria e testes de toxicidade foi avaliada a eficiência deste tratamento. Nos testes de toxicidade com S. cerevisiae na mistura dos corantes, Acid Blue 40 com Acid Red 114, mostraram que as leveduras são resistentes as concentrações as quais foram expostas. Nos testes de toxicidade com Artemia salina na mistura dos corantes, Acid Blue 40 com Acid Red 114, mostraram uma mortalidade de 23,33% na concentração de 0,100 g L-1 . Esta sensibilidade maior dos organismos expostos a combinação dos corantes é notada quando comparada com os organismos expostos aos corantes isolados. As sementes expostas a combinações dos corantes mostraram uma mortalidade similar as sementes expostas aos corantes isolados / Abstract: The shortage of drinking water is always in focus to be a prerequisite for life. In large cities it is evident as a concern that determines the lives of billions of people, and a feature that moves the economy and public health. It is essential in industries moving the economy, and many of them times out as effluent is not subjected to the necessary treatments before being returned to watercourses, which was first removed. This research aims to improve the stain removal methods Acid Red 114 and Acid Blue 40 from the effluent from textiles with the use of coagulation and flocculation process. Since untreated effluents generate ecological problems, with a large environmental impact, its treatment is essential to prevent contamination of our water sources. The chosen method of treatment was the coagulation / flocculation to be widely used in wastewater treatment plants (wastewater treatment plants) and have a good efficiency and low cost. With the use of spectrophotometry and toxicity tests evaluated the efficacy of this treatment. toxicity tests with S. cerevisiae in the mixture of dyes, Acid Blue 40 with Acid Red 114, showed that yeast concentrations which were exposed are tough. In toxicity tests with Artemia salina in the mixture of dyes, Acid Blue 40 with Acid Red 114, showed a mortality of 23.33% at a concentration of 0.100 g L-1. This increased sensitivity of the organisms exposed to the combination of dyes is noted when compared with organisms exposed to the isolated dye. Seeds exposed to combinations of dyes showed similar mortality seeds exposed to the isolated dye / Mestre
76

The use of trash fish wastewater and inorganic fertilizers in larval fish food chains : the ecological consequences and the potential applications in aquaculture /

Chan, Hing. January 1995 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1995. / Includes bibliographical references (leaf 215-231).
77

Mécanismes d'acclimatation et d'adaptation moléculaire des crustacés à la salinité / Mechanisms of acclimatization and molecular adaptation of crustaceans to salinity

Thabet, Rahma 04 June 2016 (has links)
Ce travail entre dans le cadre d’une meilleure compréhension des mécanismes de réponse des crustacés au facteur salin. Nos travaux ont démontré que les abondances des copépodes et branchiopodes dans la saline de Sfax sont régulées principalement par les concentrations en sels et la température. Des expérimentations réalisées en laboratoire ont permis de déterminer les salinités optimales pour les trois espèces de copépodes majoritaires (Bryocamptus sp., Oithona nana, Pararcartia grani) et du branchiopode Artemia salina, Une approche biochimique focalisée sur A. salina a montré qu’il assurait son osmorégulation par l’utilisation de l’énergie dépendante de la gestion de ses stocks de protéines, glucides et lipides, et par la mise en œuvre de réponses physiologiques antioxydantes. Une étude exhaustive de la bibliographie a permis de monter que la pompe transmembranaire Na+/K+ ATPase est un élément clé de la gestion de l’osmolarité cellulaire. L’analyse des gènes, ARNm et protéines correspondants à sa sous unité alpha (primordiale pour la fonction) a révélé : i) l’existence d’un gène unique au sein des invertébrés (excepté pour les nématodes), ii) une grande diversité du nombre et de la longueur des introns, iii) un phénomène d’épissage alternatif, et iii) une conservation de domaines protéiques transmembranaires. Enfin, une étude comparative de l’activité de la Na+/K+ ATPase entre deux écrevisses Astacus astacus (espèce native d’Europe) et Procambarus clarkii (espèce invasive en Europe) a démontré que seule l’espèce invasive montrait une activité élevée lors de stress salin ; ce qui pourrait expliquer en partie son aptitude à coloniser des nouveaux milieux. / The aim of our investigations was to increase your understanding of the mechanisms of crustacean’s response to salinity changes. We revealed that, in the Sfax solar saltern, the copepods and branchiopod abundances are mainly regulated by salinity and temperature. Experiments in the laboratory allowed defining the optimum of salinity for the most abundant copepod species (Bryocamptus sp, Oithona nana, Pararcartia grani) and for the branchiopod Artemia salina. An biochemical approach focused on Artemia salina (euryhaline species) showed that he ensured his energy uptake for osmoregulation by the regulation of their internal protein, carbohydrate and lipid contents. In addition, antioxidative reactions are induced to compensate the physiological disruption. A review of bibliography allowed revealing that the transmembrane pump Na+/ K+ ATPase is primordial for the cellular osmolality regulation. The structural analyses of the gene, mRNA and proteins coding alpha subunit in invertebrates showed : i) the existence of a unique gene (except for nematodes), ii) variability in the number and length of introns, iii) an alternative splicing phenomen, and iiii) high conservation of the ten transmembrane protein domains. Finally, a comparative study of the activity Na+/K+ ATPase for two crayfish species (Astacus astacus, native European species; Procambarus clarkia, alien American species) during salt stress demonstrated that only the invasive species have high Na+/K+ ATPase activity; which can explain its ability to colonize various environments.
78

A bioinorganic study of some cobalt(II) Schiff base complexes of variously substituted hydroxybenzaldimines

Shaibu, Rafiu Olarewaju January 2008 (has links)
Syntheses of Schiff bases were carried out by reacting salicylaldyhde, ortho-vanillin, para-vanillin or vanillin with aniline, 1-aminonaphthalene, 4- and 3-aminopyridine, and also with 2- and 3-aminomethylpyridine. The various Schiff bases obtained from the condensation reaction were reacted with CoCl₂.6H₂0, triethylamine stripped CoCl₂.6H₂0 or Co(CH₃COO)₂ to form cobalt(Il) complexes of ratio 2:1. The complexes obtained from cobalt chloride designated as the "A series" are of the general formulae ML₂X₂.nH₂0 , (L = Schiff base, X = chlorine) while those obtained from cobalt acetate or triethylamine stripped cobalt chloride denoted as "B" and C" are of the general formulae ML₂. nH₂0. The few complexes that do not follow the general formulae highlighted above are: IA [M(HL)₃.Cl₂], (L = N-phenylsalicylaldimine), 4A = (MLCl₂), (L = N-phenylvanaldiminato), 7 A and 21 A (ML₂), (L = N-naphthyl-o-vanaldiminato, and N-methy-2-pyridylsalicylaldiminato respectively), 8A = MLCI, (L = N-naphthylvanaldiminato), 12A = M₂L₃Cl₂, (L = N-4-pyridylvanaldiminato), 15A (MLCI), (L = N-3-pyridyl-o-vanaldiminato). The ligands and their complexes were characterized using elemental analyses and cobalt analysis using ICP, FT-IR spectroscopy (mid and far-IR), NIR-UV/vis (diffuse reflectance), UV/vis in an aprotic and a protic solvents, while mass spectrometry, ¹HNMR and ¹³CNMR, was used to further characterized the ligands. The tautomeric nature of the Schiff bases were determined by examining the behaviour of Schiff bases and their complexes in a protic (e.g. MeOH) and non-protic (e.g. DMF) polar solvents. The effects of solvents on the electronic behaviour of the compounds were also examined. Using CDCl₃, the NMR technique was further used to confirm the structures of the Schiff bases. The tentative geometry of the complexes was determined using the spectra information obtained from the far infrared and the diffuse reflectance spectroscopy. With few exceptions, most of the "A" series are tetrahedral or distorted tetrahedral, while the "B + C" are octahedral or pseudooctahedral. A small number of complexes are assigned square-planar geometry owing to the characteristic spectral behaviour shown. In order to determine their biological activity, two biological assay methods (antimicrobial testing and brine shrimp lethality assay) were used. Using disc method, the bacteriostatic and fungicidal activities of the various Schiff bases and their respective complexes to Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa as well as Aspergillus niger, were measured and the average inhibition zones are tabulated and analysed. Both the Schiff bases and their complexes showed varying bacteriostatic and fungicidal activity against the bacteria and fungus tested. The inhibition activity is concentration dependent and potential antibiotic and fungicides are identified. To determine the toxicity of the ligands and their corresponding cobalt(II) complexes, brine shrimp lethality assay was used. The LD₅₀ of the tested compounds were calculated and the results obtained were tabulated for comparison.
79

Vliv opakovaného rozmrazení na nutriční účinnost nauplií Artemia salina pro raná vývojová stádia ryb / The influence of repeated defrosting on nutritional efficiency of Artemia salina nauplii for early developmental stages of fish

HULAN, Petr January 2012 (has links)
Nutritional efficiency of deeply frosted and repeatedly defrosted zooplankton has not been totally clarified, and it is often questioned, however, the nutrients composition and effect of such deteriorated feed are missing. The aim of this study was to assess nutritional eddiciency of repeatedly defrosted nauplia Artemis salina, as well as changes in their chemical composition on the basis of the growth, survival and presence of the deformations in early ontogeny of Japanese medaka ( Oryzias latipes). The samples of fresh hatched artemia nauplii served as a control group. The experiment was carried out with samples of live nauplii, permanently frosted at -14°C, defrosted to 4°C and again frosted and defrosted to 25°C and frosted again. The larvae of medaka in the period of one week after shift to the exogenous nutrition were examined. Before the commencement of the experiment the composition of samples in terms of nutrient, amino acids and fatty acid contents was determined. The results proved that Oryzias latipes fed with live artemia not only grew better but also survived more that other fis in other treatments. No deformations were recorded Fish fed frozen food survived better than those fed with live Artemia. It was also found that fish fed live Artemia seems to be the highest however from the amino acid point of view it seems to be more appropriate to freeze it to -14°C, defreeze to 25°C and refreezing to -4°C. as for the fatty acids Artemia adjusted by the permanently freezing to -14°C. The processes of thawing and repeated freezing of artemia nauplii result in leaching of some nutrients but in the thickening of some others.
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Provozní ověření vlivu krmení raného plůdku jeseterovitých ryb obohacenými naupliemi žábronožky na jejich přežití a rychlost růstu

STARÝ, Jakub January 2018 (has links)
The purpose of the experiment was to verify of the influence of enriched artemia salina on the growth and survival of American paddlefish larvae (Polyodon spathula) in operating conditions. The control group was compared with group which was fed by artemia enriched by preparation Red pepper. Control group was fed by nonenriched artemia. This preparation contained increased amount of vitamins A, C, D3 and E, but especially HUFA, mainly DHA (docosahexaenoic acid). The larvae were fed by artemia only one week and then they were fed gradually by dry mixture for larvae. After a five-day co-feeding they were fed only by dry mixture for larvae. The whole experiment was 4 weeks. In the group which was fed by enriched artemia was statistically higher average weight (247.80 +- 40.36 mg) and average length of body (31.19 +- 1.03 mm) versus the control group. Average weight of control group was 140.76 +- 23.06 mg and average lenght of body was 25,27 +- 0.73 mm. Also average survival of the two groups was statistically different at the end of the experiment. The group which was fed by enriched artemia demonstrated an average survival 15.43 +- 2.90 %, while the control group only 2.20 +- 1.92 %. Only rate of cannibalism was not influenced by enrichment of artemia. But these results, mainly survival was negatively influenced by Ichthyophthirius multifiliis, which was detected on the skin after five days of the experiment. Another parameter was average amount of individual fatty acids in the body of larvae from both groups. In the group which was fed with enriched artemia was found statistically higher level of LA (linoleic acid), LNA (-linolenic acid) and DHA. On the other hand, higher levels of ARA (arachidonic acid), EPA (eicosapentaenoic acid) and DPA (docosapentaenoic acid) was found in control group.

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