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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.
101

THE SYNAPTIC CIRCUITS UNDERLYING OLFACTORY PROCESSING AND REPRESENTATIONS IN THE INSECT BRAIN: CHARACTERIZATION AND PLASTICITY OF THE MUSHROOM BODY CALYX

Butcher, Nancy J. 16 August 2010 (has links)
Sensory information is processed and encoded by neural networks. In order to understand how the nervous system is able to rapidly integrate and store sensory information, knowledge of the connections and properties of the neurons in these circuits is required. The fruit fly Drosophila melanogaster provides a particularly powerful species to investigate the neural circuits of the olfactory system because in addition to possessing a simple olfactory system amenable to circuit analysis, a host of genetic reagents are available, including the GAL4-UAS system for targeted gene expression. The mushroom bodies, paired structures historically implicated in olfactory learning and memory, receive olfactory information at the mushroom body calyx from second-order olfactory projection neurons (PNs). Within the calyx, individual PN axonal boutons are surrounded by dendritic arborizations from intrinsic Kenyon cells (KCs) and each tiny cluster constitutes a single microglomerulus. Cells that connect the calyx with other areas of the brain, extrinsic neurons (ENs), also contribute to microglomeruli. Most of these contain the neurotransmitter, GABA, and are presumed to be inhibitory. In this study, the synaptic characteristics, neural circuits, and plasticity of calycal cells have been investigated using a combination of serial section electron and confocal microscopy. The findings reveal several new features of the circuits in the calyx: 1) The calyx contains three ultrastructurally distinct types of PN boutons that are heterogeneous in shape and exhibit subtle differences in synaptic densities. 2) All PN boutons form both ribbon and non-ribbon synapses, and from their smaller size and fewer postsynaptic partners, non-ribbon synapses may possibly become converted to ribbon synapses after activity; the olfactory signal may then be transmitted more strongly and efficiently at ribbon synapses. 3) PN boutons with an electron-dense cytoplasm have the most ribbon synapses per unit area of membrane as well as the highest ratio of ribbon to non-ribbon synapses, and thus may be more active and efficient than other boutons. 4) KC neurites are not exclusively postsynaptic in the calyx and can form occasional ribbon synapses, the functional interpretation of which awaits identification of their postsynaptic partners and vesicle contents. 5) Each PN bouton may contribute input to a single dendritic KC claw at about three presynaptic sites. For the postsynaptic side, a single claw receives input from individual presynaptic sites that must be highly redundant. 6) There may be important processing of the olfactory signal by local circuits formed by ENs in the calyx; ENs form synaptic connections with PNs, KCs, and other ENs. 7) Extensive serial synapses link EN terminals into a network, presumed to be GABAergic and inhibitory, that extends between microglomeruli and may be autaptic. 8) The structure and synaptic connectivity of microglomeruli may undergo changes after adult emergence. 9) vGAT and GAD1-GAL4 lines drive ectopic expression of marker genes in KCs and are not reliable reporters of GABA-positive cells. 10) Previously identified calycal ENs (MB-C1, MB-C2/C3, MB-CP1) are not immunopositive for GAD1, a marker of GABA-containing cells. 11) A network of ENs expressing a GABA phenotype differently innervates anatomically and functionally discrete areas of the honeybee calyx, and in addition the density of innervation may change with alterations in age and/or experience.
102

Chemical signalling in the Drosophila brain : GABA, short neuropeptide F and their receptors

Enell, Lina E. January 2011 (has links)
Gamma-aminobutyric acid (GABA) and short neuropeptide F (sNPF) are widespread signalling molecules in the brain of insects. In order to understand more about the signalling and to some extent start to unravel the functional roles of these two substances, this study has examined the locations of the transmitters and their receptors in the brain of the fruit fly Drosophila melanogaster using immunocytochemistry in combination with Gal4/UAS technique. The main focus is GABA and sNPF in feeding circuits and in the olfactory system. We found both GABA receptor types in neurons in many important areas of the Drosophila brain including the antennal lobe, mushroom body and the central body complex. The metabotropic GABAB receptor (GABABR) is expressed in a pattern similar to the ionotropic GABAAR, but some distribution differences can be distinguished (paper I). The insulin producing cells contain only GABABR, whereas the GABAAR is localized on neighbouring neurons. We found that GABA regulates the production and release of insulin-like peptides via GABABRs (paper II). The roles of sNPFs in feeding and growth have previously been established, but the mechanisms behind this are unclear. We mapped the distribution of sNPF with antisera to the sNPF precursor and found the peptide in a large variety of interneurons, including the Kenyon cells of the mushroom bodies, as well as in olfactory sensory neurons that send axons to the antennal lobe (paper III). We also mapped the distribution of the sNPF receptor in larval tissues and found localization in six median neurosecretory cells that are not insulin-producing cells, in neuronal branches in the larval antennal lobe and in processes innervating the mushroom bodies (paper IV). In summary, we have studied two different signal substances in the Drosophila brain (GABA and sNPF) in some detail. We found that these substances and their receptors are widespread, that both sNPF and GABA act in very diverse systems and that they presumably play roles in feeding, metabolism and olfaction. / At the time of doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.
103

Genetic Dissection of the Neural Circuitry Underlying Memory Stability in Drosophila: A Dissertation

Keene, Alex Carl 22 August 2006 (has links)
Understanding how memory is formed requires looking beyond the genes involved to the neural circuitry and temporal aspects of memory. In this dissertation I have focused my investigation on Dorsal Paired Medial (DPM) neurons, two modulatory neurons essential for memory in Drosophila. DPM neurons highly express the amnesiac (amn) gene, which encodes for a putative pre-pro-neuropeptide. amn function in DPM neurons is required for memory. Here I provide evidence that DPM neurons are cholinergic and that acetylcholine (ACh) and AMN act as co-transmitters essential for DPM function. In order to investigate the temporal requirements of DPM output I blocked transmitter release during discrete intervals in the memory process using shibirets1 and tested flies for shock and sugar-reinforced memory. These experiments demonstrated that stable memory requires persistent transmitter release from DPM neurons. Furthermore these results suggest AMN and DPM neurons act as general stabilizers of mushroom body dependent memory. To further investigate the neural circuitry underlying DPM function I disrupted DPM projections onto the mushroom body lobes by ectopically expressing DScam17-2::GFP in DPM neurons. Flies with DPM neurons that predominantly project to the mushroom body α´/β´ lobes exhibit normal memory, and blocking transmitter release from the mushroom body prime lobes neurons themselves abolishes memory indicating DPM neuron-mushroom body α´/β´ neuron interaction that are critical for memory. Taken together, the experimental evidence presented here are used to provide a rudimentary model of the neural circuitry involved in memory stability, where DPM neurons form a recurrent feedback loop with the mushroom body α´/β´ lobe neurons and act to stabilize odorspecific conditioned memories at Kenyon cell synapses.
104

Cs-137 i Svamp : Dataanalysrutiner för gammaspektroskopi

Nordman, David January 2018 (has links)
Kärnkraftsolyckan i Tjernobyl ledde till en spridning av radioaktiva ämnen över Europa och Sverige. År 2018 är det 32 år sedan kärnkraftsolyckan ägde rum och den enda radioaktiva isotopen som finns kvar i det svenska ekosystemet som följd av olyckan i en betydande mängd är Cs-137, på grund av dess 30-åriga halveringstid. Genom att bestämma aktiviteten hos svamp kan halten Cs-137 i mark uppskattas. Hösten 2018 kommer det tvärvetenskapliga massexperimentet Strålande jord att utföras i syfte att kartlägga denna halt i hela Sverige. Syftet med detta examensarbete var att nå resultat som är användbara vid aktivitetsbestämning av svamp. Ett numeriskt verktyg för analys av data ifrån gammaspektroskopi har konstruerats. Två metoder för att beräkna händelser (counts) i energitoppar i gammaemissionsspektra har formulerats och varit byggstenar för det vidare arbetet. Under arbetets gång har följande bestämts: effektiviteten hos en high purity germanium (HPGe) detektor, aktiviteten hos två svampprover, attenueringskoeffcienten av 662 keV-gamma för samma svampprover samt för vatten. För att kunna approximera en burk med svamp som en isotropt strålande punktkälla och få goda resultat behöver aktivitetsmätningarna göras med ett långt avstånd mellan provet och detektorn. Att mätningar måste göras på ett långt avstånd gör att approximationen bara är lämplig för ett svampprov med hög aktivitet, vilket blev tydligt i detta examensarbete då aktiviteten hos ett lågaktivt svampprov inte kunde bestämmas med god statistik trots att enskilda mätningar gjordes under närmare en veckas tid. Systematiska fel har inte tagits hänsyn till i detta arbete, utan enbart statistisk osäkerhet. / The nuclear disaster in Chernobyl brought radioactive substances over Europe and Sweden. In 2018 it has passed 32 years since the disaster and the only radioactive isotope that reamins in the swedish ecosystem at a signicant level is Cs-137. By determining activity of mushroom, the amount of Cs-137 in the ground can be estimated. In the fall of 2018, the interdisciplinary mass-experiment Strålande jord will take place with the purpose to map this amount all over Sweden. The purpose of this work was to reach results that could be of use when determining the activity of mushroom. A numerical tool for analysing data from gamma spectroscopy has been constructed. Two different methods for calculating counts in energy peaks from gamma emission spectra have been made and have been the basis for the further work. During this work the following has been determined: The efficiency of a high purity germanium (HPGe) detector, the activity of two different mushroom samples, the attenuation coefficient of gamma at 662 keV for these samples and for water. In order to be able to approximate a can filled with mushroom as an isotropic radiating point source and get accurate results, the activity measurements need to be carried out with a great distance between the sample and the detector. A consequence of this is that this approximation is only suitable for high-activity mushroom, which became evident when the activity of a low-activity mushroom could not be decided with decent statistics even though single measurements were carried out in almost a weeks time. Systematic errors are not considered during this work, only statistical uncertainties.
105

Produção, economicidade e parâmetros energéticos do cogumelo Agaricus blazei: um enfoque de cadeia produtiva

Herrera, Ozana Maria [UNESP] 12 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-12Bitstream added on 2014-06-13T19:42:01Z : No. of bitstreams: 1 herrera_om_dr_botfca.pdf: 943761 bytes, checksum: f04cac39b9303236f928e730000a945f (MD5) / Nos últimos anos tem sido intensa a busca por atividades agrícolas que conciliem a produção de alimentos com preservação ambiental e viabilidade econômica e social. A globalização modificou as relações econômicas de forma ampla e definida, obrigando todos os setores da economia a realizarem rápidas adaptações para garantir sua participação e sobrevivência no mercado. Essas transformações impactam, de forma gradual e constante, a organização da produção agroindustrial. A eficiência, nos sistemas agroindustriais, provém de relações entre preços e produtividade dos fatores de produção (terra, capital e trabalho) e da tecnologia. São importantes também a minimização dos custos de transação ao longo das cadeias, e um eficiente sistema de coordenação ou de governança. Por outro lado, os cogumelos medicinais podem ser importantes aliados na resolução de muitos problemas, desde o aproveitamento de resíduos agroindustriais até a produção de medicamentos utilizados no combate à diversas doenças. O Agaricus blazei é um cogumelo originário da Mata Atlântica brasileira e vem ganhando credibilidade como produto nutracêutico e medicinal em mercados internacionais... / In the last years it has been intense the search for agricultural activities that reconcile the production of foods with environmental preservation and economical and social viability. The globalization modified the economical relationship in a wide and defined way, forcing all of the sections of the economy to perform it fast adaptations to guarantee their participation and survival in the market. Those transformations impact, in a gradual and constant way, the organization of the agroindustrial production. The efficiency in the agroindustrial system, comes from relationships between prices and productivity of the production factors (land, capital and work), from technology, and others factors analyzed traditionally, derived of the minimization of the cost transaction along the chains, and of an efficient coordination or governance system. Otherwise, the medicinal mushrooms can be important allies in the resolution of many problems, which go from the utilization of agroindustrial residue to the production of medicaments used to fight several diseases. Agaricus blazei is a mushroom...(Complete abstract, click electronic access below)
106

Crescimento micelial de Ganoderma lucidum em diferentes substratos e relação com concentração de β-Glucanas, atividade antioxidante e efeitos sobre o desempenho de coelhos / Ganoderma lucidum mycelium growth in different substrates with reference to β-glucans, anti-oxidant capacity and effects on rabbits performance

Henrique, Katia Atoji 16 December 2015 (has links)
Ganoderma lucidum é um cogumelo medicinal consumido tradicionalmente nos países asiáticos que apresenta diversos efeitos benéficos comprovados. Apesar de todos os estudos sobre seus compostos bioativos, a melhor forma de enriquecimento de meios de cultivo visando aumentar a produção destes compostos ainda se mantém incerta. Além disso, poucos trabalhos tratam dos efeitos sobre o desempenho de animais de produção. Para testar diferentes meios de cultivo de micélio de G. lucidum, foram testados resíduos agrícolas (fermentação em estado sólido) e diferentes açúcares e aminoácidos (em meios de cultura com ágar), para avaliar o crescimento do micélio de G. lucidum. O fornecimento de farinha com micélio de G. lucidum obtido por fermentação em meio sólido (grãos de trigo) para coelhos também foi avaliado. O micélio de G. lucidum desenvolveu-se bem nos resíduos agrícolas, destacando-se a casquinha de soja que apresentou maior taxa de crescimento e também maior concentração de β-glucanas. No experimento em placas, o G. lucidum também se desenvolveu bem, destacando-se os meios que continham celobiose e tirosina, que apesar de apresentarem menores taxas de crescimento e crescimento total em 10 dias, produziram micélios com maior concentração de β-glucanas e capacidade antioxidante em equivalentes trolox (TEAC), respectivamente. Os coelhos não apresentaram sinais de intolerância ao consumo de ração com diferentes concentrações farinha com micélio de G. lucidum. Todos os parâmetros de desempenho e avaliação de carcaça foram adequados à idade em que foram abatidos. A avaliação histológica dos órgãos apresentou alterações nas células renais (tubulares e glomerulares), apontando para uma possível lesão renal conforme aumentou a concentração de farinha com micélio na ração. A avaliação histomorfométrica resultou em maior altura de vilosidade de íleo e menor largura de vilosidade de jejuno na concentração 0,5%, e redução do diâmetro de cripta conforme o aumento da concentração de farinha com micélio. Estes resultados indicam a possibilidade de estudos mais aprofundados sobre os aspectos de utilização de celobiose e tirosina para produção de compostos bioativos, e sobre aspectos de toxicidade do micélio deste cogumelo para segurança no fornecimento para animais. / Ganoderma lucidum is a medicinal mushroom traditionally consumed in Asian countries that presents several beneficial effects already verified. Despite all studies about their bioactive compounds, the best cultivation media enrichment aiming to increase the production of these compounds is still uncertain. Besides, few studies are related to the performance of production animals. In order to test different cultivation media for G. lucidum mycelia, agricultural residues (solid state fermentation) and different sugars and aminoacids (in culture media with agar), were tested to evaluate G. lucidum mycelium growth. Supply of flour with G. lucidum mycelia obtained by solid state fermentation (wheat grain) for rabbits was also evaluated. Mycelium of G. lucidum developed very well in all agricultural residues, soybean hulls was the residue that presented higher growth rate and higher concentration of β-glucans. In the cultivation media experiment, G. lucidum also developed well, media that contained cellobiose and tyrosine, despite presenting lower growth rates and total growth within 10 days, produced mycelia with higher concentration of β-glucans and trolox equivalent antioxidant capacity (TEAC), respectively. Rabbits did not show any sign of intolerance to feed with different concentrations of flour with G. lucidum mycelium. All performance parameters and dressing percentages were adequate to the age at which they were slaughtered. Histological evaluation of organs presented alterations in renal cells (tubular and glomerulus), indicating a possible renal lesion according to the increase of flour with mycelium in feed. Histomorphometric evaluation showed increased vilous height in ileum and decreased vilous width of jejunus at 0.5% concentration, and decrease in crypt diameter according to the increase of concentration of flour with mycelium in feed. These results indicate the possibility of more studies regarding the aspects about cellobiose and tyrosine utilization for the production of bioactive compounds, and about toxicity of this mushroom mycelia, assuring the safety in supplying this product for animails.
107

Crescimento micelial de Ganoderma lucidum em diferentes substratos e relação com concentração de β-Glucanas, atividade antioxidante e efeitos sobre o desempenho de coelhos / Ganoderma lucidum mycelium growth in different substrates with reference to β-glucans, anti-oxidant capacity and effects on rabbits performance

Henrique, Katia Atoji 16 December 2015 (has links)
Ganoderma lucidum é um cogumelo medicinal consumido tradicionalmente nos países asiáticos que apresenta diversos efeitos benéficos comprovados. Apesar de todos os estudos sobre seus compostos bioativos, a melhor forma de enriquecimento de meios de cultivo visando aumentar a produção destes compostos ainda se mantém incerta. Além disso, poucos trabalhos tratam dos efeitos sobre o desempenho de animais de produção. Para testar diferentes meios de cultivo de micélio de G. lucidum, foram testados resíduos agrícolas (fermentação em estado sólido) e diferentes açúcares e aminoácidos (em meios de cultura com ágar), para avaliar o crescimento do micélio de G. lucidum. O fornecimento de farinha com micélio de G. lucidum obtido por fermentação em meio sólido (grãos de trigo) para coelhos também foi avaliado. O micélio de G. lucidum desenvolveu-se bem nos resíduos agrícolas, destacando-se a casquinha de soja que apresentou maior taxa de crescimento e também maior concentração de β-glucanas. No experimento em placas, o G. lucidum também se desenvolveu bem, destacando-se os meios que continham celobiose e tirosina, que apesar de apresentarem menores taxas de crescimento e crescimento total em 10 dias, produziram micélios com maior concentração de β-glucanas e capacidade antioxidante em equivalentes trolox (TEAC), respectivamente. Os coelhos não apresentaram sinais de intolerância ao consumo de ração com diferentes concentrações farinha com micélio de G. lucidum. Todos os parâmetros de desempenho e avaliação de carcaça foram adequados à idade em que foram abatidos. A avaliação histológica dos órgãos apresentou alterações nas células renais (tubulares e glomerulares), apontando para uma possível lesão renal conforme aumentou a concentração de farinha com micélio na ração. A avaliação histomorfométrica resultou em maior altura de vilosidade de íleo e menor largura de vilosidade de jejuno na concentração 0,5%, e redução do diâmetro de cripta conforme o aumento da concentração de farinha com micélio. Estes resultados indicam a possibilidade de estudos mais aprofundados sobre os aspectos de utilização de celobiose e tirosina para produção de compostos bioativos, e sobre aspectos de toxicidade do micélio deste cogumelo para segurança no fornecimento para animais. / Ganoderma lucidum is a medicinal mushroom traditionally consumed in Asian countries that presents several beneficial effects already verified. Despite all studies about their bioactive compounds, the best cultivation media enrichment aiming to increase the production of these compounds is still uncertain. Besides, few studies are related to the performance of production animals. In order to test different cultivation media for G. lucidum mycelia, agricultural residues (solid state fermentation) and different sugars and aminoacids (in culture media with agar), were tested to evaluate G. lucidum mycelium growth. Supply of flour with G. lucidum mycelia obtained by solid state fermentation (wheat grain) for rabbits was also evaluated. Mycelium of G. lucidum developed very well in all agricultural residues, soybean hulls was the residue that presented higher growth rate and higher concentration of β-glucans. In the cultivation media experiment, G. lucidum also developed well, media that contained cellobiose and tyrosine, despite presenting lower growth rates and total growth within 10 days, produced mycelia with higher concentration of β-glucans and trolox equivalent antioxidant capacity (TEAC), respectively. Rabbits did not show any sign of intolerance to feed with different concentrations of flour with G. lucidum mycelium. All performance parameters and dressing percentages were adequate to the age at which they were slaughtered. Histological evaluation of organs presented alterations in renal cells (tubular and glomerulus), indicating a possible renal lesion according to the increase of flour with mycelium in feed. Histomorphometric evaluation showed increased vilous height in ileum and decreased vilous width of jejunus at 0.5% concentration, and decrease in crypt diameter according to the increase of concentration of flour with mycelium in feed. These results indicate the possibility of more studies regarding the aspects about cellobiose and tyrosine utilization for the production of bioactive compounds, and about toxicity of this mushroom mycelia, assuring the safety in supplying this product for animails.
108

Influência do substrato no cultivo e na composição química do cogumelo Pleurotus florida

Figueiró, Gláucia Garcia [UNESP] 02 September 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-09-02Bitstream added on 2014-06-13T20:59:58Z : No. of bitstreams: 1 figueiro_gg_me_ilha.pdf: 1622216 bytes, checksum: 6223c00cd61193ae623babff3571f19a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho teve por objetivo evidenciar os principais componentes químicos que influenciam o cultivo do cogumelo Pleurotus florida, bem como avaliar a composição química dos corpos de frutificação cultivados em diferentes resíduos agrícolas. Para tanto, foram utilizados seis resíduos agrícolas: palha de arroz (PA), palha de feijão (PF), palha de trigo (PT), palha de sorgo (PS), folha de bananeira (FB) e sabugo de milho (SM). Estes resíduos, coletados na Fazenda de Ensino, Pesquisa e Extensão da UNESP, Campus de Ilha Solteira, foram analisados quanto aos teores de macro (N, P, K, Ca, Mg) e micronutrientes (Fe, Mn e Zn), lignina, celulose, hemicelulose, cinzas e relação C/N. Foram avaliados: o tempo necessário para a colonização do substrato (corrida micelial), o início da formação de primórdios, o tempo total de cultivo, o número de cogumelos, a produção e a eficiência biológica utilizando a fórmula: EB = (peso fresco dos cogumelos/peso seco do substrato inicial) x 100. Além disso, os cogumelos foram avaliados quanto aos teores de macro (N, P, K, Ca e Mg) e micronutrientes (Fe, Mn e Zn) e o teor de proteínas. O substrato PF apresentou resultados semelhantes para produção (189,8 g/kg-1), EB (89,2%) e número de cogumelos (12) à PA, substrato utilizado tradicionalmente no cultivo de Pleurotus em escala comercial. Não foi possível atribuir apenas a um fator químico as altas produções e EB observadas em PA e PF e muito menos para a baixa produção em PS (77,8 g/kg-1) e SM (53,2 g/kg-1). No geral, substratos com conteúdo de N ao redor de 1,0%, relação C/N em torno de 45%, baixo teor lignina, alto conteúdo de cinzas e maiores teores de P, K e Ca foram os melhores para o cultivo de P. florida. Entre os macronutrientes analisados, P. florida apresentou maiores teores de K, seguido por P. O Ca e o Mg estiveram presentes em pequenas quantidades nos corpos... / This study aimed to show the main chemical components that influence the cultivation of the mushroom Pleurotus florida, and evaluate the chemical composition of fruiting bodies grown on different agricultural residues. For that, six agricultural residues were used: rice straw (RS), bean straw (BS), wheat straw (WS), sorghum straw (SS), banana leaf (BL) and cob of maize (CM). These wastes were collected at Teaching, Research and Extention Farm of UNESP, Campus of Ilha Solteira, analyzed for the levels of macro (N, P, K, Ca, and Mg) and micronutrients (Fe, Mn and Zn), lignin, cellulose, hemicellulose, ash and the C/N ratio. Was evaluated: spawn run time, earliness, the total time of cultivation and mushroom number, production and biological efficiency using the formula: EB = (fresh weight of mushrooms/dry weight of initial substrate) x 100. Moreover, the mushrooms were evaluated for levels of macro (N, P, K, Ca and Mg) and micronutrients (Fe, Mn and Zn) and protein content. The substrate BS showed similar results for yield (189,8 g/kg-1), EB (89,2%) and number of mushrooms (12) as RS substrate traditionally used for the cultivation of Pleurotus in commercial scale. Unable to allocate only the chemical factors and the high yields and EB observed in BS and RS, much less for the yield low in SS (77,8 g/kg-1) and CM (53,2 g/kg-1). In general, substrates with N content of around 1.0%, C/N ratio around 45%, low lignin content, high ash content, increased by higher levels of P, K, Ca were the best for the cultivation of P. florida. Among the macronutrients analyzed, P. florida with higher contents of K, followed by P. The Ca and Mg were present in small amounts in fruiting bodies. Among the micronutrients, Zn was present in high amount, followed by Fe and Mn. P. florida showed high ability to accumulate Zn. The mushrooms obtained in this work could not be considered a source of minerals... (Complete abstract click electronic access below)
109

Produção de proteases coagulantes por espécies de Pleurotus em resíduos vegetais da Amazônia

NEVES, Kilma Cristiane Silva 19 March 2014 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-06-13T15:00:48Z No. of bitstreams: 1 Kilma Cristiane Silva Neves.pdf: 2678760 bytes, checksum: 781a39173a3ab80aeb45daef6f49b148 (MD5) / Made available in DSpace on 2016-06-13T15:00:48Z (GMT). No. of bitstreams: 1 Kilma Cristiane Silva Neves.pdf: 2678760 bytes, checksum: 781a39173a3ab80aeb45daef6f49b148 (MD5) Previous issue date: 2014-03-19 / Fungal species are already available in the market and the mushrooms have been reported as producers of milk coagulating enzymes for cheese production. The objective of this study was to investigate the growth of Pleurotus florida DPUA 1534 and Pleurotus ostreatus DPUA 1533 in vegetable substrate to select a species with potential proteolytic coagulant for the application in the food industry. The results of vertical mycelial growth, although P. florida DPUA 1534 and P. ostreatus DPUA 1533 have colonized natural residues tested, P. florida DPUA 1534 was the species that showed a significant increase (p> 0.05) after 15 days given that determined the choice of this species for the production of the mushroom. In producing the substrate formulated based on cupuaçu bark supplemented with rice bran 20%, 20 mycelial inoculum discs (Ø = 10 mm) resulted in better biological efficiency (14.2%) and the remaining analyzes were performed with P. florida DPUA 1534 produced under those conditions. The analysis showed the mushroom highlighted in the following nutritional characteristics P. florida DPUA 1534 proteins (25.94%), carbohydrate (49.72%), iron (89.82%) and zinc (85.08%) and the presence of all essential amino acids. In the crude extract of the mushroom P. florida DPUA 1534 to coagulant activity and the AUC ratio was 67.68 and 2.15, respectively. Optimum activity was shown at pH 7.0 at 40 ° C. The enzyme extract was stable between 25 ° C and 40 ° C and at pH between 4 and 10 showed about 80 to 90% of activity in the first 90 minutes of incubation. The enzymatic extract showed susceptibility to inhibitors of the serine protease class (90%), metalloprotease (93%), cysteine proteases (92%) and aspartic protease (94%). The most effective compound was Pepstatin A, suggesting the presence of aspartic protease enzymes showing aspartic residues in the active site, indicating the possibility of its application in the dairy industry. Regarding toxicity results showed that P. florida DPUA 1534 produces proteases with biological activity on Artemia salina (LC50 = 25,5μg) and showed hemolytic activity in blood of sheep trading in ascending order with respect to extract concentrations (0, 2 to 1.0 mL), LC50 = 363,88μg and LC50 = 241,51μg after 1h and 24h of incubation, respectively. The in vivo test indicated that the extract when administered at a dose of 1000 mg.Kg-1 in rats, no deaths or clinical signs of toxicity in any of the treated animals did not cause significant changes in haematological and biochemical parameters when compared to the group control, and histological analyzes revealed no acute toxicity under the experimental conditions. Therefore, the extract of P. florida DPUA 1534 showed potential for use as coagulating milk. / Espécies de fungos já estão disponíveis no mercado e os cogumelos têm sido reportados como produtores de enzimas coagulantes do leite para produção de queijos. O objetivo do presente trabalho foi investigar o crescimento de Pleurotus florida DPUA 1534 e Pleurotus ostreatus DPUA 1533 em substrato vegetal para selecionar uma espécie com potencial proteolítico coagulante para fins de aplicação na indústria de alimentos. Nos resultados do crescimento micelial vertical, embora P. florida DPUA 1534 e Pleurotus ostreatus DPUA 1533 tenham colonizado os resíduos naturais testados, P. florida DPUA 1534 foi a espécie que apresentou crescimento significativo (p>0,05) ao final de 15 dias, dado que determinou a escolha dessa espécie para produção dos basidiomas. Na produção o substrato formulado a base de casca de cupuaçu suplementado com farelo de arroz 20%, inóculo de 20 discos miceliais (Ø= 10 mm) resultou na melhor eficiência biológica (14,2%) e as demais análises foram realizadas do cogumelo de P. florida DPUA 1534 produzido nessas condições. A análise dos basidiomas mostrou em destaque a seguinte característica nutricional de P. florida DPUA 1534, proteínas (25,94%), carboidratos (49,72%), ferro (89,82%) e zinco (85,08%), além da presença de todos os aminoácidos essenciais. No extrato bruto dos basidiomas de P. florida DPUA 1534 a atividade coagulante e a razão foi de 67,68 UAC e 2,15, respectivamente. A atividade ótima foi demonstrada em pH 7,0 a 40 °C. O extrato enzimático mostrou-se estável entre 25 °C e 40 °C, e na faixa de pH entre 4 a 10 apresentou cerca de 80 a 90% de atividade nos primeiros 90 minutos de incubação. O extrato enzimático mostrou susceptibilidade aos inibidores das classes de serino-protease (90%), metaloprotease (93%), cisteíno-protease (92%) e protease aspártica (94%). O composto mais eficaz foi Pepstatin A, sugerindo a presença de protease aspártica, enzimas que apresentam resíduos aspárticos no sítio ativo, indicando a possibilidade de sua aplicação na indústria de laticínios. Em relação à toxicidade os resultados demonstraram que P. florida DPUA 1534 produz proteases com atividade biológica frente à Artemia salina (CL50= 25,5μg) e apresentou atividade hemolítica em sangue de carneiro comercial em ordem crescente em relação à concentração do extrato (0,2 a 1,0 mL), com CL50= 363,88μg e CL50= 241,51μg após 1h e 24h de incubação, respectivamente. O teste in vivo indicou que o extrato quando administrado na dose de 1000 mg.Kg-1 em ratos Wistar, não ocorreu óbito ou sinais clínicos de toxicidade em nenhum dos animais tratados, não promoveu alterações significativas dos parâmetros hematológicos e bioquímicos quando comparados ao grupo controle, e as análises histológicas revelaram que não houve toxicidade aguda nas condições do experimento. Portanto, o extrato de P. florida DPUA 1534 apresentou potencial para utilização como coagulante do leite.
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Aproveitamento de resíduos madeireiros e da agroindústria regional para o cultivo de fungos comestíveis de ocorrência na região Amazônica

Sales-campos, Ceci 30 May 2008 (has links)
Made available in DSpace on 2015-04-20T12:31:50Z (GMT). No. of bitstreams: 1 Ceci Sales-Campos.pdf: 2811573 bytes, checksum: 7be484fbb01156c4d85c71184e7aedc4 (MD5) Previous issue date: 2008-05-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / There is in the Amazon region a great amount of residues (wood, agro-forest and agroindustrial), which has been underestimated, and constitutes potential sources for the cultivation of edible fungi in the region. The biodiversity of the Amazon draws the worldwide interest about its resources, specially for the microorganisms with potential for commercial use. Amongst these organisms there are the edible and medicinal mushrooms. In this way, the cultivation of edible mushrooms in the state of Amazon could represent an alternative source for the regional development. Thus, this research had the objective to test the development of different wild edible mushroom species, as well as testing the use of different regional residues in the substrate composition for their cultivation. Preliminary tests were carried out with the species Pleurotus ostreatus, Lentinus strigosus, Polyporus arcularius and with five wood residues (marupá, pau de balsa, amapá doce, muiratinga and breu) and two of agro-industrial origin (sugar cane bagasse and the stem of pupunheira palm tree). In this experimental phase the micelial growth of the fungi in substrates made from the above residues was evaluated. In the subsequent tests, based on the results obtained in these preliminary tests, Pleurotus ostreatus, two wood residues (marupá and pau de balsa sawdust) and two agro-industrial ones (sugar cane bagasse and stem of pupunheira palm tree) were chosen. All the substrates were supplemented with a mixture of cereal brans (rice, wheat and corn), were evaluated for: 1- production of basidioma (yield), productivity, through the biological efficiency of formulated substrates, loss of the organic matter, biological behavior of the strain (period of colonization, primordia formation and production of basidioma) referred in Chapter 2; 2- Mineral composition of: the raw material, the initial and spent substrates (post-harvest), and of the mushroom (Chapter 3); 3 - Nutritional composition of: the mushroom, the raw material and substrates (Chapter 4). In general, it can be concluded that the strain of P. ostreatus has developed in a satisfactory way in all tested substrates, making it possible to use these residues (with low or no commercial value) in the mushroom cultivation. Moreover, it is an ecologically correct use of the residues, since it prevents the discard of these residues in the environment, promoting the bioconversion into added-value product edible mushroom and of high nutritional value, and that could become a source of regional sustainable development / Há na região amazônica uma grande quantidade de resíduos (madeireiros, agroflorestais e agroindustriais), cujo quantitativo tem sido subestimado, os quais constituem fontes potenciais para utilização no cultivo de fungos comestíveis na região. A riqueza promovida pela biodiversidade da Amazônia começa a despertar interesse mundial a cerca de seus recursos, com acentuada atenção para os microrganismos com potencial de utilização comercial. Dentre estes organismos encontram-se os fungos comestíveis e medicinais. Desta forma, o cultivo de cogumelos comestíveis no estado do Amazonas, poderá representar uma fonte alternativa para o desenvolvimento regional. Assim, esta pesquisa teve por meta testar o desenvolvimento de diferentes espécies de cogumelos comestíveis nativos, bem como testar o uso de diferentes resíduos regionais na composição de substratos para o cultivo dos mesmos. Foram feitos inicialmente testes preliminares com as espécies Pleurotus ostreatus, Lentinus strigosus e Polyporus arcularius e com cinco resíduos madeireiros (marupá, pau de balsa, amapá doce, muiratinga e breu) e dois de origem agroindustrial (bagaço cana-de-açúcar e estipe de pupunheira). Nesta fase experimental avaliou-se o crescimento micelial das espécies fúngicas em substratos à base dos resíduos anteriormente citados. Nos testes subseqüentes, com base nos resultados obtidos nestes testes preliminares, escolheu-se o P. ostreatus, dois resíduos madeireiros (marupá e pau de balsa) e dois agroindustriais (bagaço de cana-deaçúcar e estipe de pupunheira). Todos os substratos foram também suplementados com uma mistura de farelo de cereais (arroz, trigo e milho), sendo avaliados: 1- produção de basidiomas (rendimento), produtividade, através da eficiência biológica dos substratos formulados, perda da matéria orgânica, comportamento biológico da linhagem (período de colonização, de formação dos primórdios e de produção dos basidiomas) abordados no Capítulo 2; 2- Composição mineral da matéria-prima, dos substratos iniciais, residuais (pós-colheita) e do cogumelo (Capítulo 3); 3- Composição nutricional do cogumelo, da matéria-prima e dos substratos de cultivo (Capítulo 4). De uma forma geral, conclui-se que a linhagem de P. ostreatus desenvolveu-se de uma forma satisfatória em todos os substratos testados, o que viabiliza o uso destes resíduos (com baixo ou nenhum valor comercial) para a fungicultura. Além disso, é uma aplicação ecologicamente correta, uma vez que evita que estes resíduos sejam descartados na natureza, permitindo-lhes a bioconversão em um produto de valor agregado cogumelo comestível e de elevado valor nutricional e que poderá vir a tornar-se uma fonte de desenvolvimento sustentável regional

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