Programa de Pós-Graduação em Biotecnologia - PPGBIOTEC/ICB
URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/6089
O Programa de Pós-Graduação em Biotecnologia (PPGBIOTEC) é um programa do Instituto de Ciências Biológicas (ICB) da Universidade Federal do Pará (UFPA). O PPGBIOTEC fornece a base teórica para o desenvolvimento de projetos em duas áreas de concentração e quatro linhas de pesquisa, definidas de acordo com a competência e experiência de orientação dos docentes do programa: Área de Bioprospecção: linhas de pesquisa: (i) química orgânica de biomoléculas e metabolômica; e (ii) genômica, transcriptômica, proteômica e bioinformática de microrganismos e plantas (Bactéria, Archaea e Eukarya). Área de Biotecnologia Aplicada: linhas de pesquisa: (i) saúde humana e veterinária; e (ii) produção de insumos e processos industriais.
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Item Acesso aberto (Open Access) Acúmulo de colesterol por Mycobacterium smegmatis como possível modulador da biossíntese de lipomanana e lipoarabinomanana(Universidade Federal do Pará, 2015-02-26) SANTOS, Ana Cristina Doria dos; SENA, Chubert Bernardo Castro de; http://lattes.cnpq.br/8620752020290438Mycobacterial cell wall is a hallmark of Mycobacterium genus, constituted of bioactive lipids and glycoconjugates: phosphatidylinositol mannoside (PIMs), lipomannan (LM) and lipoarabinomannan (LAM). The chronic infection inside lung macrophages is related with cholesterol accumulation into host cells as an alternative source of carbon and energy to maintain the bacilli with its physiological functions. To understand the activity of these immunomodulatory glycoconjugates during adaptation under the unusual environment inside the host infected cells, the present work propose to investigate the possible modulation of LM/LAM biosynthesis in Mycobacterium smegmatis (saprophytic) after culture in minimal medium (MM), supplemented with glycerol and/or cholesterol. Our results showed that saprophytic bacilli are able to accumulate the cholesterol and change the bacterial physiology due to slow growth and restrict cell density. Furthermore, the cholesterol consumption decreased the accumulation of PIMs and promoted morphological changes and bacterial aggregates, even maintaining the cell wall with its specific physic-chemistry characteristic (alcohol-acid resistance). The most impressive change after cholesterol consumption was the LAM biosynthesis, which showed distinct electrophoresis migration, compatible to high molecular weight of LAM from non-saprophytic bacilli (from 25 – 30 KDa to 30 – 50 KDa). These results showed that cholesterol consumption, when utilized as principal alternative of carbon and energy source, is able to induce physiological changes in mycobacteria, mainly in LAM biosynthesis, one of the most immunoregulatory molecules of cell wall. Ours data suggest that similar changes in mycobacteria may occur inside the granuloma, and that changes may help the evolution of tuberculosis to chronic and multibacillary form, hallmarked by immunodeficient aspect against the bacilli.Item Acesso aberto (Open Access) Análise da expressão gênica de pacientes com adenocarcinoma gástrico associado ao vírus Epstein-Barr(Universidade Federal do Pará, 2024-08) SILVA, Valéria Cristiane Santos da; MOREIRA, Fabiano Cordeiro; http://lattes.cnpq.br/5745396559731337Infection with the Epstein-Barr virus (EBV) is one of the risk factors for gastric cancer (GC). Epstein-Barr is a virus with oncogenic activity and was the first to be associated with malignant diseases such as lymphomas and carcinomas. Thus, EBV detection can be performed both by in situ hybridization and, currently, by using RNA sequencing techniques to identify the presence of viral genes in samples. In this context, aiming to better understand the EBV-positive subtype, this study proposed a molecular classification based on RNA sequencing of 76 tumor samples from patients diagnosed with GC. RNA sequencing of the samples was performed, and molecular classification was done using the Kraken2 software. Of the 76 samples, 8 were considered positive according to the adopted method. Subsequently, to understand the different mechanisms by which EBV might be acting in gastric cancer, we analyzed the patterns of human gene expression in samples classified as positive and negative. In our study, there are approximately 834 differentially expressed genes, of which 92 have an AUC greater than 0.85. These genes are associated with tumor progression, cellular metabolism, and innate and adaptive immunity. Additionally, viral genes expressed in the positive samples were evaluated, and we found manifestations of both lytic phase and latent phase genes. Finally, our study presents an efficient strategy for the molecular classification of EBV-positiveItem Acesso aberto (Open Access) Análise e caracterização do genoma mitocondrial: um estudo de caso de Cyprinodon sp. e Arapaima gigas(Universidade Federal do Pará, 2025-05) MACEDO, Daralyns Borges; RAMOS, Rommel Thiago Juca; http://lattes.cnpq.br/1274395392752454; https://orcid.org/0000-0002-8032-1474The advancement of next-generation sequencing technologies has enabled large-scale characterization of mitochondrial genomes across various species. However, even among fish — the group with the highest number of sequenced mitochondrial genomes — only 9.7% of valid species are represented in genetic databases. This gap limits conservation programs, which rely on genetic data to guide management strategies. The genus Cyprinodon, composed of several threatened species restricted to isolated habitats, is particularly vulnerable to habitat loss and interspecific hybridization. In this context, the present study aimed to sequence and characterize the mitochondrial genome of Cyprinodon sp., in order to clarify phylogenetic relationships and evolutionary aspects of the Cyprinodontidae family. The sample was sequenced using the Illumina HiSeq platform, assembled with Megahit software, and analyzed using tools such as MitoZ, Circos, ClustalW, MrBayes, and Figtree. The complete mitogenome comprises 16,500 bp and contains 37 genes. Concurrently, Arapaima gigas, an iconic Amazonian species historically important to fisheries, is currently threatened with extinction and classified as “Data Deficient” by the IUCN. In the Tocantins River, heavily impacted by human activities, fishers from 25 communities reported the near disappearance of the species, with only one recent sighting on Jaracuera Island. The disappearance of A. gigas has severe economic consequences for local communities. Without collaboration between fishery managers and local populations, the species faces an imminent risk of regional extinction, further exacerbated by the lack of data on its fishing dynamics in northern Brazil.Item Acesso aberto (Open Access) Análise morfológica e molecular dos filamentos das nadadeiras pélvicas do peixe pulmonado Lepidosiren paradoxa(Universidade Federal do Pará, 2015-12-18) LIMA, Sérgio Queirós; SCHNEIDER, Igor; http://lattes.cnpq.br/4453558334183860The Lepidosiren paradoxa species belongs to Dipnoi order, along with two genre and are considered true lungfishes. Adult males of L. paradoxa differ from females by the presence of filaments in the pelvic fin. These filaments resemble those found in gills of fish and neotenic salamanders. These filaments are grow and become vascularized during the reproduction period. In this work we tested the hypothesis that the pelvic filament of L. paradoxa share morphological and molecular characteristics with gill filaments. Thus, we performed morphological and molecular analyses of the filaments of the pelvic fins between the dry and rainy seasons. Morphological analysis was perfomed through hematoxylin and eosin (HE) and scanning electron microscopy (SEM). Finally, we quantified gene expression of gill markers by RT-PCR using pectoral fin as reference. The mean length and standard deviation of the filaments during rainy and dry season were 4,31mm of ± 0.186 and 1,63mm ± 0.104, respectively. In the SEM images, we observed with a few cell microvilli and/or microplicae and some smaller cells. In the HE analyzes we found that the filaments have uniform epithelium formed with four layers of cells being filled by connective tissue and finally become more vascularized the rainy season. Molecular analysis through RT-PCR did not show any change when compared to the pectoral fin and between the stations. In conclusion, despite morphological and molecular similarities between gill filaments and pelvic fin filaments, our findings do not support a role for L. paradoxa pelvic filaments in gas exchange.Item Acesso aberto (Open Access) Análise proteômica de cultura macrófagica tratada com ácido kójico(Universidade Federal do Pará, 2023-07) ALMEIDA, Heyder Coutinho; SANTOS, Agenor Valadares; http://lattes.cnpq.br/9530734927662735; https://orcid.org/0000-0002-2690-2841Kojic acid (AK) is a natural fungal secondary metabolite, produced by some species of Aspergillus, Penicillium and Acetobacter, through the direct biotransformation of carbon substrates such as glucose, sucralose, ethanol, among others. AK was originally isolated in Japan, in 1907, from Aspergillus oryzae mycelia, it is used in the cosmetic industry in the form of gels and soap and is used to obtain the effect of whitening the skin by inhibiting the enzyme tyrosinase, reducing the production of formation of melanin, it also blocks the formation of pigmentation and evens out the skin tone. It is also applied as a food additive for the prevention of enzymatic browning, as it is a metal chelator and a potent antioxidant. Although AK has numerous biological functions, only recently studies on in vitro proliferation and cytotoxicity have been reported, but still limitedly regarding its effect on immune cells. Macrophages are among the most important defense cells that specifically recognize and respond to foreign bodies, apoptosis cells and pathogens. Through the activation process, there is an increased proliferation of macrophages, which undergo various morphological changes, such as an increase in dissemination and adhesion abilities, phagocytosis activity, ROS generation, antigen presentation and cytokine production. According to the classification of biological functions, our results revealed that in both Kojic acid concentrations, the 14 expressed proteins have a predicted function related to cell cycle and redox processes.Item Acesso aberto (Open Access) AutoAssemblyD software para submissão e gerenciamento de montagem de genomas a partir de modelos XML(Universidade Federal do Pará, 2014-01-24) VERAS, Adonney Allan de Oliveira; SILVA, Artur Luiz da Costa da; http://lattes.cnpq.br/7642043789034070Technologies for second-generation sequencing provided a major breakthrough of the genome, making its use a landmark that has revolutionized biology. These platforms are characterized by a reduction in sequencing time, high data production and low cost per base sequenced, however, these devices produce data mostly consist of short readings which represents a major challenge for reconstruction of the genome due to this new feature readings of computational tools had to be developed to accomplish the task of assembling their example we Velvet, AllPaths, Abyss, SOAPdenovo2, Edena. However, most of these applications are executed through command lines extended and composed of several parameters must follow the standard syntax to use, because in case of errors in the syntax is the possibility of not obtaining the best result, with the aim of solve this problem we present the AutoAssemblyD that besides providing the use of these assemblers through a graphical interface also enables the management of these executions remotely.Item Acesso aberto (Open Access) Avaliação do potencial biotecnológico de compostos isolados de Swietenia macrophylla no tratamento de câncer(Universidade Federal do Pará, 2015-11-30) BARRETO, Leilane de Holanda; MONTENEGRO, Raquel Carvalho; http://lattes.cnpq.br/0043828437326839Swietenia macrophylla (mahogany) is a species of plant widely known for its therapeutic potential. The main constituents isolated extracts of this plant are structures known as limonoids. The limonoids also have several biological activities, among them, antitumor activity. The aim of this study was to evaluate the antitumor potential of the extract and limonoid obtained from leaves of S. macrophylla in cancer cell lines. Cytotoxicity to 5 cancer cell lines and normal revealed that the extract had cytotoxic effect in colorectal cancer cell lines (HCT-116 and HT-29), as the limonoids were cytotoxic for colorectal cancer (HCT-116) and melanoma (SKMEL-19). Given these results, we selected the limonoid L3 and HCT-116 cell line to evaluate the mechanism of action, as well as the HT-29 lineage, which has the TP53 gene mutated for comparison as possible of the compound mechanism of action, once it was less sensitive to L3. Moreover, L3 showed more selective for tumor cells. None of the compounds caused hemolysis of erythrocytes in mice. To evaluate the antiproliferative action of L3, the clonogenic assay was performed, where the two lines there was a significant reduction of colonies, however this reduction was more significant in HCT-116. The L3 compound also has caused death by apoptosis in a dose-dependent manner in the lines, where the number of cells in apoptosis was higher in HCT-116. To evaluate DNA damage, it was held the comet assay, which showed that L3 cause damage to the DNA of the two cancer cell lines, with greater damage index in HCT-116. The assessment of cell cycle distribution of cells after treatment with L3 showed that there was blocking the cycle at the G2 / M phase, mainly in HCT-116 (45% of the cells). From these data, it conducted a study of genes involved in this phase of the cycle, from analysis of their expression by RT-PCR. The ATM gene, which is activated by DNA damage activates the CHK-2 which in turn phosphorylates p53 protein. p53 protein can activate the transcription of p21 gene, which triggers cell cycle stopped, or activate cell death pathways. In this study, we found increased expression of genes ATM, CHK-2, TP53, ARF in a dose dependent in both cacer cell lines, and this expression was higher in HCT-116 cell line. The expression of p21 was increased in HCT-116, while in HT-29 decreased, this is due to the fact that HT-29 possess the mutant TP53 gene, then your protein does not work properly. As the path of apoptosis was evaluated caspase-3 gene and the anti-apoptotic gene BCL-2. There was increase in the expression of caspase-3 mainly in HCT-116 and decrease of BCL-2. These results suggest that L3 may be causing damage to the DNA of cells, triggering a cellular signaling pathway dependent on p53. To evaluate the toxicity of S. macrophylla extract, it was held the acute toxicology testing in mice, where the extract did not cause any changes in the physiological parameters of animals. As the claustogenicidade test (micronucleus) also showed that the extract is not mutagenic in the mouse bone marrow cells.Item Acesso aberto (Open Access) Avaliação do viés GC em plataformas de sequenciamento de nova geração(Universidade Federal do Pará, 2015-03-05) PINHEIRO, Kenny da Costa; RAMOS, Rommel Thiago Jucá; http://lattes.cnpq.br/1274395392752454The emergence of high throughput sequencing (HTS) platforms increased the amount of data making feasible to obtaining complete genomes. Despite the advantages and the throughput produced by these platforms, the high or low genomic coverage in the regions of the genome can be related to GC content. This GC bias may affect genomic analyzes and the genomic/transcriptomic analysis based on de novo and reference approach. In addition, the ways to evaluate the GC bias should be fit to data with different profiles of the GC vs coverage relationship, such as linear and quadratic. Thus, this work proposes the use of Pearson's Correlation Coefficient (r) to analyze the correlation between GC content and coverage, allowing to identify the strength of linear correlation and detect nonlinear associations, beyond identify a relationship between GC bias and sequencing platforms. The positive and negative signs of r also allow us to infer directly and inversely proportional relationships, respectively. To evaluate the bias, we used the data of Corynebacterium pseudotuberculosis obtained from different sequencing technologies to identify if the CG bias is related to used platforms.Item Acesso aberto (Open Access) Biodiversidade bacteriana durante a fermentação espontânea de frutos de açaí (Euterpe oleracea)(Universidade Federal do Pará, 2015-06-22) MOURA, Fábio Gomes; ROGEZ, Hervé Louis Ghislain; http://lattes.cnpq.br/5202118426597590Açai (Euterpe oleracea) fruits (AF) and a wide variety of products derived from this fruit are an example of success of a local and typically Brazilian product on the global market. The AF suffer spontaneous fermentation during postharvest due mainly to its high microbial load and the favourable intrinsic and extrinsic parameters. The biodiversity of microbial community in AF and their evolution between three geographical origins and two fermentation conditions were examined. Culture-independent methods based on 16S rRNA from fifteen samples revealed that Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes and Acidobacteria were the most abundant phyla. At genus level, were identified Massilia (taxon with more than 50 % of sequences remaining constant during the 30 h of fermentation), Pantoea (taxon with the highest increase during fermentation), Naxibacter, Enterobacter, Raoultella and Klebsiella, forming the carposphere bacterial microbiota of AF. Attributes related to plant growth promotion (siderophores) and others compounds e.g. poly-3-hydroxybutyrate (PHB) and violacein in response to stress conditions could improve the Massilia preponderance. Beta diversity showed that quality parameters of AF (pH, soluble solids, titratable acididy and lipids) and elemental analysis (C, N, H and C/N ratio) were unable to establish microbial patterns in AF. This research offers new insights and perspectives of the indigenous bacterial community composition on AF as a function of spontaneous fermentation during postharvest.Item Acesso aberto (Open Access) Bioprospecção de leveduras com potencial para a produção de carotenoides presentes em uma microrregião do bioma Amazônia(Universidade Federal do Pará, 2024-11) LUCAS, David Cristian Rodrigues; CHISTÉ, Renan Campos; http://lattes.cnpq.br/0583058299891937; https://orcid.org/0000-0002-4549-3297Carotenoids are bioactive compounds used as natural pigments and are found in plants, animals, algae and microorganisms. Some of these compounds are precursors of vitamin A and have benefits to human health such as strengthening the immune system and reducing the risk of chronic degenerative diseases. In industry, the production of carotenoids is obtained mainly by chemical synthesis or through algae and plant extracts. However, with the growing concern about utilization of chemical additives in food by many consumers, the interest in obtaining them through biotechnological processes and diverse microorganisms may synthesize them, such as yeasts. In this work, an exploration study was carried out focused on molecular identification of carotenoid-producing yeasts available in a microregion of Amazonia biome, with the aim of highlighting promising microorganisms for future industrial applications. Samples were collected from leaves, flowers, soil, and bark trees, among them, 4 promising strains were isolated and identified from phyllosphere of philodendron (Philodendron hederaceum): Rhodosporidiobolus ruineniae (PH-18(I)), Rhynchogastrema noutii or Hannaella pagnoccae (dPH-8(I)), Leucosporidium egoroviorum or Lyomyces sp. (dPH-8(II)), and Rhodotorula diobovata or Rhodotorula glutinis (PH-22(II)). The strain PH-18(I) showed a biomass yield of 0.26% to 0.76% and total carotenoid content of 139.70 μg/g of dry biomass. The strain dPH-8(I) showed a biomass yield of 0.43% to 0.96 % and total carotenoid content of 54.26 μg/g. The strain dPH-8(II) demonstrated a biomass yield of 0.35% to 1.12% and total carotenoid content of 52.71 μg/g, while the strain PH-20(II) demonstrated a biomass yield of 11.63 % to 23.67 % and total carotenoid content of 44.98 μg/g. The carotenoids identified in this study were 13Z-β-carotene, (all-E)-β-carotene and 9Z-β-carotene, being (all-E)-β-carotene the majority. Results found in this study highlight a promising perspective for future applications of carotenoid-producing yeasts in the Amazonia biome, being an excellent alternative to replace the process of obtaining carotenoids by synthetic means or by exploitation of vegetal sources.Item Acesso aberto (Open Access) Busca e classificação sistemática das proteínas oxigenases com ferro não hêmico em plantas(Universidade Federal do Pará, 2015-03-06) SOUSA, Kellen Rayanne Matos de; DARNET, Sylvain Henri; http://lattes.cnpq.br/4586614214029929Nonheme iron oxygenase proteins shares a conserved domain consisting of eight histidines, and they can be found in eukaryotes and prokaryotes organisms and participate in important pathways of lipid biosynthesis. To understand the evolutionary relationship among these proteins, we performed comparative and phylogenetic analyzes in prokaryotes and eukaryotes that allowed a classification of this family, nonexistent until now. The search of sequences resulted in a collection of 448 proteins, belonging to 58 organisms previously selected. The multiple alignment made with MAFFT (BLOSUM 62; L-INS-i) showed the presence of three histidine-rich motifs, with conserved spacing among them. The classification made with CLANS software has generated 28 clusters through of similarity among sequences. Two clusters contain sequences that had no similarity to proteins already characterized, and 48 sequences were not assigned to any of the 28 clusters. In the collection, 119 sequences are derived from plants, distributed in 7 clusters corresponding to C4 methysterol monooxygenase, C5 sterol desaturase, fatty acid hydroxylase, sphingolipid C4 monooxygenase, aldehyde decarbonylase, β-carotene hydroxylase and Acyl-ACP desaturase functions. Phylogenetic analysis using maximum likelihood method with PhyML tool showed the formation of well-defined groups that were similar to generated by CLANS. These results start to fill a gap existing so far about the evolutionary relationship and classification of nonheme iron oxygenases. Also, suggest that within this family there are still proteins with unknown functions, reinforcing the need for more studies of functional characterization.Item Acesso aberto (Open Access) Caracterização antigênica, físico-química e biológica do vírus BE AR 701405, obtido a partir de mosquitos da espécie Psorophora (Jan) ferox, capturados em Altamira – Pará(Universidade Federal do Pará, 2014-03-26) ARAÚJO, João Batista dos Santos; LEAL, Élcio de Souza; http://lattes.cnpq.br/1158983666415285The BE AR 701405 virus was isolated from a pool of Psorophora (Jan.) ferox mosquitoes captured in the municipality of Altamira, Para state, Northern Brazil, in 2006. The objective of this study was the physicochemical, biological and antigenic characterization of the BE AR 701405 virus in order to provide data for it taxonomic classification. Newborn mice inoculated by intracerebral route showed evidences of neurological manifestations, such as chill and motor disorders after the infection with the virus BE AR 701405. Cytophatic effect (CPE) was in infected Aedes albopictus C6/36 cells was not clearly observed, however in VERO cells CPE was observed after 48 hors post infection. The virus load was determined in 10-4,1 LD50/ 0.02 mL and the titer after DCE analysis was calculated in 10−2,6 LD50/0,02 mL. The BE AR 701405 virus reacted antigenically with Pixuna virus hiperimmune serum. In conclusion, the studied vírus was sensible to the DCA solvent suggesting that it is an enveloped virus. Furthermore, by serology this virus was identified as a member of the group A, genus Alphavirus, family Togaviridae, more closely related to Pixuna virus. In addition, newborn mice, as well as C6/36 and VERO cells demonstrated to be sensible to the infection by the BE AR 701405 vírus. Further studies are needed to better understand the antigenic relationship between the BE AR 701405 virus and Pixuna virus.Item Acesso aberto (Open Access) Caracterização molecular in silico de uma mono-oxigenase lítica de polissacarídeo cianobacteriana(Universidade Federal do Pará, 2024-03) VIRGOLINO, Rodrigo Rodrigues; GONÇALVES, Evonnildo Costa; http://lattes.cnpq.br/8652560763793265; https://orcid.org/0000-0003-2221-1995 País de Nacionalidade BrasilLytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that catalyze the oxidative cleavage of β(1-4) glycosidic bonds and have attracted great attention due to importance in increasing the efficiency in degradation of recalcitrant polymeric substrates, in synergism with the action of hydrolytic enzymes, as an accessory function. However, LPMOs act via oxidative cleavage rather than hydrolysis. In industrial applications, LPMOs of fungal origin are the most frequent, while other taxonomic groups have been described as possible alternative sources of these enzymes. In the present study, we aimed to identify and characterize in silico a LPMO of cyanobacterial origin with putative functions in chitin depolymerization. The search for sequence similarity and conservation of domains with other characterized LPMOs identified a 289 AA protein from the cyanobacterium Mastigocoleus testarum of the Nostocales Order, being a probable LPMO of the CAZy-AA10 class. This protein is referred to as MtLPMO10. Phylogenetic analysis revealed that MtLPMO10 is homologous to the Tma12 protein from the fern Tectaria macrodonta, with 52.11% identity, which was the first LPMO characterized as originating from the plant kingdom. The occurrence of shared structural and functional patterns with other AA10 class LPMOs, as well as the existence of variations in these established patterns, contributed to the understanding of the biological functions of this class of enzymes. The predicted protein tertiary arrangement by the AlphaFold server pointed out structural features common to LPMOs, especially a histidine brace composed of His31 and His132 and an immunoglobulin-like domain consisting of antiparallel beta strands. Molecular dynamics simulation (MD) allowed evaluating the enzyme-substrate affinity, using an initial pose based on data obtained from the literature. There was stability of the MtLPMO10-chitoheptaose complex during 100ns of MD, while the MtLPMO10-celloheptaose complex broke apart in 30ns of MD. Also, there was a shorter Cu(I)-H4 distance in the first complex compared to the Cu(I)-H1 distance (averages 6.0 ± 0.7 Å and 7.9 ± 0.7 Å, respectively), suggesting a C4-type regioselectivity, as defined for Tma12. This study highlights the existence of lytic polysaccharide monooxygenases in cyanobacteria and paves the way for further investigations related to this enigmatic class of enzymes and their potential use in biotechnological applications.Item Acesso aberto (Open Access) Cianotoxinas em ostras e em águas de cultivo da costa norte do Brasil(Universidade Federal do Pará, 2016-08-31) CABRAL, Jardecicléia Patrícia da Silva; SCHNEIDER, Maria Paula Cruz; http://lattes.cnpq.br/3901112943859155Cyanobacteria are photosynthetic prokaryotic organisms and under conditions favorable to their growth can form blooms. They are also capable of producing cyanotoxins, secondary metabolites that have a toxic effect on eukaryotic organisms including man. As part of phytoplankton the cyanobacteria participate in the food chains, thus the ingestion of shellfish, that have been continuously fed toxic cyanobacteria and accumulated the toxins in their tissues generates the possibility of transfer to the man through their consumption bringing serious risks to their health. There is still very little research on the contamination (by cyanotoxins) of shellfish intended for human consumption. Therefore, this study was to verify the occurrence of cyanotoxins in culture waters and in the tissue of oysters destined for human consumption. The water and oyster samples were collected from two municipalities located in the northeast of Pará. The cyanotoxins research was performed using High Performance Liquid Chromatography (HPLC). The cyanobacteria present in the water, isolated and cultured from oyster shells were identified. No microcystins and saxitoxins were detected in water samples and oyster extracts from both growing sites. However, three genera of cyanobacteria - Aphanizomenon, Oscillatoria and Phormidium were identified in Curuçá and three genera of cyanobacteria in São Caetano de Odivelas - Aphanothece, Oscillatoria and Phormidium, all known to contain toxic species. The presence of saxitoxins in extracts from cyanobacterial cultures was detected from the oyster shells of both growing sites, indicating the presence of toxic species despite the absence of bloom. In this study, it was verified that the cultivation of oyster sites are suitable for consumption, free of contamination by microcystins and saxitoxins, however, it is necessary to implement specific legislation and the monitoring of these crops in order to ensure consumer health.Item Acesso aberto (Open Access) Co-cultivo de embriões bovinos com células-tronco adultas derivadas de tecido adiposo(Universidade Federal do Pará, 2014-09-05) NASCIMENTO, Hamilton Silva do; MIRANDA, Moysés dos Santos; http://lattes.cnpq.br/3354029928888919The in vitro embryo production (IVP) is a biotechnology used to increase the reproductive potential of genetically superior animals, embryos produced in vitro are inferior in quality when compared in vivo. Techniques trying improve the rates of in vitro produced embryos. One technique is the co-culture system using somatic cells that remove toxic metabolites and protect against oxidative stress. Mesenchymal stem cells derived from adipose tissue (CTA) are multipotent cells that secrete growth factors and cytokines. The stem cells were used in in vitro co-culture of bovine embryos at different concentrations in order to improve the protocol PIVE. CTAs underwent differentiation into three mesenchymal lineages, and was performed immunophenotyping of specific membrane markers of MSCs. The cleavage rate was assessed on the second day after fertilization and blastocyst rate on the seventh day when they were stored for counting the total number of cells and gene expression. The results were analyzed by ANOVA, T-test and post-test of Fisher, adopting a significance level of 5%. Treatment of co-cultivation with CTAs significantly influenced the formation of the blastocyst, the total number of cells in embryos and correlated gene expression pluripotency and carbohydrate metabolism. These results showed increased production rate and quality of embryos produced in vitro co-culture with CTAs compared to co-culture with granulosa cells. These results also indicate that the constant presence of CTAs in co-culture is superior to conditioning with CTAs. Checked the effects of CTAs can occur through soluble factors or via exosomes secreted by CTAs. Future studies are needed to clarify the possible cause for positive effects observed in this work by the CTAs in co-cultivation.Item Acesso aberto (Open Access) Correlação metabólica entre fungos endofíticos de amaryllidaceae e as plantas hospedeiras na busca por substâncias bioativas(Universidade Federal do Pará, 2016-06-30) SILVA, Suelen Mata da; SANTOS, Alberdan Silva; http://lattes.cnpq.br/5976702134131016The endophytic fungi are a promising source of secondary metabolites with biotechnological applications. These microorganisms inhabit the interior of plant tissues without causing any damage to the host and as a result of this interaction can produce some of the substances synthesized by the host plant. In this context the use of endophytic fungi as a source of biomolecules in the replacement of plant represents economic and environmental advantages. Species in the Amaryllidaceae family produce alkaloids and other metabolites with biological activities. Among these species include Crinum americanum L. and Hymenocallis littoralis (Jacq.) Salisb. However, no data on endophytic fungi from species of the family were found. In the view of the above stated the aim of this work was to scrutinize the biotechnological potential of endophytes of C. americanum and H. littoralis as compared to host plants and to study the interactions between endophytes and host plant. As results 94 endophytic fungi were isolated from two species of the investigated Amaryllidaceae, of which 49 were identified and belonging to the Colettotrichum class, Acremonium, Trichoderma and Fusarium. It was noted that of the total strains tested 56 showed lipids in its extracts, 21coumarins, 29 anthrones and 2 showed alkaloids. 12 strains of endophytic fungi were selected which presented the best results in the detection of classes of metabolites and the extracts were analyzed by Thin-layer chromatography and by Gas chromatography-mass spectrometry in comparison with the methanolic extracts of host plants. It was noted the correlation between the classes of metabolites detected in extracts of the endophytic fungi and host plants, indicating that these micro-organisms are able to produce some of the same substances that the host plants and the assessment of antimicrobial activity highlighted some extracts with activity against Candida parapsilosis. The methanolic extract of leaves of H. littoralis and endophytic fungus MIBA 0796 presented the most relevant outcomes with percentage of inhibition above 60% against yeast. With the study of the interaction between C. americanum endophytes and the host plant it can observe that microorganisms act within the plant cells and in favorable conditions develop and occupy intercellular spaces as well. This location of the Endophytes in plant tissues may facilitate the exchange of genetic material between plants and microorganisms explaining how metabolic correlation found in this research.Item Acesso aberto (Open Access) Detecção de potenciais corticais antecipatórios em sinais de eletroencefalografia (EEG) durante a condução de carros(Universidade Federal do Pará, 2015-03-16) SANTOS, Fredson Carmo dos; CARVALHO, Schubert Ribeiro de; http://lattes.cnpq.br/1496976331707751; GOMES, Bruno Duarte; http://lattes.cnpq.br/4932238030330851The recognition of the driver’s intention from electroencephalographic signals (EEG) may be useful in the development of brain computer interface (BCI) to be used in synergy with intelligent vehicles. This can be beneficial to improve the quality of interaction between the driver and the car, for example, providing a response from the smart car aligned with the intention of the driver. In this study, the anticipation is considered as the cognitive state that leads to specific actions while driving a car. Therefore, we propose to investigate the presence of anticipatory patterns in EEG signals while driving vehicles to determine two specific actions (1) left and (2) turn right, a few milliseconds before such actions take place. An experimental protocol was proposed to record EEG signals of 5 individuals as they operate a virtual reality simulator non-invasive - it was designed for this experiment - which simulates driving a virtual car. The experimental protocol is a variant of the paradigm of contingent negative variation (CNV) with Go and Nogo conditions in virtual reality training system. The results of this study indicate the presence of anticipatory patterns observed in slow cortical potentials in the time domain (medium EEG signal) and the frequency (Power Spectra and phase coherence). This opens a range of possibilities in the development of BCI systems - based on anticipatory signals - that connect the driver to the intelligent vehicle favoring a decision-making to assess the intentions of drivers may eventually prevent accidents while driving.Item Acesso aberto (Open Access) Efeito do meio condicionado por células tronco mesenquimais derivadas de tecido adiposo na maturação de oócitos bovinos e posterior desenvolvimento embrionário in vitro(Universidade Federal do Pará, 2016-07-29) VALENTE, Juliana Vieitas; MIRANDA, Moysés dos Santos; http://lattes.cnpq.br/3354029928888919Stem cells are known for their property of self-renewal, differentiation into various cell lineages and immunomodulatory capabilities, in addition to express a large number of adhesion molecules, extracellular matrix proteins, cytokines and growth factor recptors, allowing interactions with other cells. They can be isolated from various tissues, but adult stem cells derived from adipose tissue stroma (MSC-d) have the advantage of being easely isolated, high yield and low morbidity. Based on this, the study hypothesis is to verify the effect of MSC-ad conditioned medium use in in vitro maturation on development rates of bovine embryos. To this end, bovine MSC ad were isolated then cultivated until the passage three (P3) in DMEM culture medium, supplemented with sodium bicarbonate, 10% fetal bovine serum (FBS), 50mL / mL gentamicin. When cultures reached 70% confluency, the medium was replaced with TCM199 supplemented with 0.2 mM pyruvate, 50 ul / ml gentamicin and 10% FBS (IVM medium). The MSC-ad were conditioned with medium TCM199 supplemented for a period of 0 (Control Group), 24 (COND-24 group), 48 (COND-48h group) and 72 hours (COND group-72h), wherein the end of each period, the supernatant medium was removed, filtered, aliquoted and frozen at -20 0 C. The medium was thawed only on MIV day, and supplemented with 0.5 uL of PMSG (concentration 7 IU / ml) and 0.5 uL of HCG. Slaughterhouse ovaries were punctured to obtain oophurus cumulus complexes (COCs) were matured for 24 hours in microdrops of conditioned mediums under mineral oil them incubated in an incubator at 5% CO 2 at 38.5 ° C. Nuclear maturation assessment was performed with 22 hours, then held 15 parthenogenetic activation of only oocytes that exhibited polar body concentration of at least 50 uM ionomycin for 5 minutes, inactivation with TCM199-Hepes 0.03g saturated with BSA, followed by incubation for 3 hours microdroplets 2mM 6-DMAP. After this period, the parthenogenesis were transferred as microdrops to a culture medium in vitro. development rates were evaluated in the second and seventh days after activation. The results were analyzed by ANOVA and Fisher's post-test adopting a significance level of 5%. For groups: Experimental CONTROL, COND-24, COND-48h and 72h-COND, we obtained the following results respectively: 83.7, 77.7, 81.4 and 76.1% of nuclear maturation; 87.5, 86.9, 74 and 80.3 and 23.8% cleavage, 27.5, 18 and 19.6% of blastocyst formation. There was no statistical difference between condinioned experimental groups (p<0.05). However, blastocyst rates were lower when compared with fresh IVM medium (42.1%) (p<0.05). This suggests that the efficiency was affected by the conditioning of the medium or freezing. Future studies should be conducted to assess the levels of growth factors, cytokines and chemokines secreted in IVM medium.Item Acesso aberto (Open Access) Estudo da combinação de preparações enzimáticas no rendimento de extração aquosa do óleo da polpa de Euterpe oleracea Martius(Universidade Federal do Pará, 2016-03-23) FERREIRA, Erika de Souza; HERMAN, Christelle Anne Nicole Paule; http://lattes.cnpq.br/8386417434654533The oil of the açai palm tree (Euterpe oleracea) fruits has a beneficial lipid profile for health with a high content of mono and polyunsaturated fatty acids, besides antioxidant substances, which provides its appreciation on the industry. The aqueous extraction of vegetable oils supported by enzymes has been widely used because of its benefits compared to the traditional processes. In this context, this work aims to identify the best combination of enzymatic preparations, which would maximize the aqueous extraction yield of the oil of the açai palm tree fruits from the pulp. The açai pulp was obtained from fruits collected in Abaetetuba during the 2015 crop. Four commercial enzymatic preparations (Novozymes) were used: Celluclast 1,5L (cellulase); Viscozyme L (endo 1,3(4) β-glucanase, xylanase, cellulase and hemicellulase); Ultrazym AFP (pectin lyase, cellulase and polygalacturonase); and Shearzyme 500L (endo 1,4-xylanase). The tests of açai oil extraction were performed by a process developed in this work with the following parameters: mean granulometry of the açai pulp of 0,75 cm; global dry matter of the aqueous mixtures of the pulp of 15%; individual enzymatic concentration of 1% (w:w) on pulp basis; constant orbital agitation of 100 rpm and vigorous agitation by hand every 30 minutes; incubation time and temperature of 4 hours and 50°C, respectively. The enzymatic preparations were tested individually (1x1) in quadruplicate, or combined (2x2; 3x3 and 4x4) in triplicate, totaling 89 tests. The negative control presented a mean yield of extraction of 34,91±11,81%, the lowest of all the tests. The tests performed with the isolated enzymatic preparations have enabled an increase of the extraction yield up to 36,66% compared to the negative control, confirming the important role of the enzymes in the aqueous extraction process. The tests performed with the enzymatic preparations combined 3x3 and 4x4 have increased the extraction yield up to 99,05% compared to the negative control, demonstrating the importance of using the combinations of enzymatic preparations. Among the different tests performed, the enzymatic preparations that stood out are Celluclast 1,5 L, Viscozyme L and Ultrazym AFP by facilitating the oil recovery with a reduce standard deviation (±3,01%). Furthermore, the extraction yield using this combination of three enzymatic preparations is statistically equal to the extraction yield using the four enzymatic preparations, which becomes interesting to the industry due to the cost reduction in the process.Item Acesso aberto (Open Access) Estudo de genômica comparativa de corynebacterium pseudotuberculosis linhagem 226 (biovar ovis)(Universidade Federal do Pará, 2015-03-10) DIAS, Larissa Maranhão; CARNEIRO, Adriana Ribeiro; http://lattes.cnpq.br/7533716053525477; http://lattes.cnpq.br/7533716053525477Corynebacterium pseudotuberculosis is a gram-positive, facultative intracellular, non-sporulating and non-encapsulated bacterium, it is non-motile although it has fimbriae, and can assume coccoid or filamentous forms (pleomorphic). Its optimum growth temperature is 37°C. This pathogen has two biovars: ovis, which usually affects small ruminants and causes caseous lymphadenitis, and biovar equi, more common in equines, bovines, camelids and bubalines, causing ulcerative lymphangitis. Its infection can lead to carcass condemnation and reduction in wool production (in ovines and caprines), milk production and meat production and, consequently, economic losses for the agricultural industry worldwide. Currently there is no effective vaccine against those illnesses. To obtain a better understanding of these species biologically, the main objective of this work is to analyze, using comparative genomics, the strain C. pseudotuberculosis 226 biovar ovis, isolated from a caprine in California, comparing it to other strains from biovars ovis and equi. The synteny analysis revealed highly conserved gene order between strain 226 and other biovar ovis strains. Phylogenomic analyses showed that the strains I19 and 267 are, respectively, the closest and the more distant phylogenetically from strain 226. Among biovar equi strains, the one with the greater phylogenomic proximity to strain 226 was strain 1/06-A. Eight pathogenicity islands were predicted, with C. pseudotuberculosis best characterized virulence genes in literature being present in island 1. No new regions related to virulence genes could be found compared to other strains. 248 orthologous genes could be found between strains I19, 267 and 226, while 282 orthologous genes could be found between strains 258, 1/06-A and 226. Based in this study it is possible to assume that strains from biovar ovis have a little varied gene repertory and strains from biovar equi have less genes shared with strain 226, reinforcing the genetic diversity between these biovars.