116 resultados para Aromatic hydrocarbon fraction


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Oil is a hydrocarbon mixture of various sizes, including saturated and aromatic compounds. Natural gas is a mixture of gaseous hydrocarbons and its main component is methane. In our society, the great demand for these fuels requires fast extraction, transportation and refining, increasing the number of accidents that compromise the environment. Oil is a finite resource and it is necessary to reduce the problems related to the question concerning environmental pollution which has encouraged the search for alternative fuel sources in our country. So today we have two major biofuels: ethanol and biodiesel. Concurrently, many studies have been done directed toward the isolation of microorganisms capable of degrading petrochemical industrial wastes, most of them using as a source of isolation soil and water collected in a contaminated environment. Isolation from alternative substrates has emerged as a new strategy that has provided satisfactory results. In this work, we present the leaf-cutter ants of the Attini tribe as a source for the isolation of micro-fungi with the potential for hydrocarbon degradation. These insects have a social way of life and a highly specialized system of intra and interspecific communication, which is based on the recognition of individuals through volatile chemical compounds, the majority hydrocarbons, stored in their exoskeleton. The micro-environment exoskeleton of Attini ants (genus Atta) used in this work proved to be a rich source of microbial biodiversity, as other studies have found. The flotation isolation technique applied here allowed the achievement of 214 micro-fungi, 118 representatives of the dematiaceous fungi group and 96 hyaline filamentous fungi. They were submitted to toluene degradation tests and at least one strain of each genus presented good results, namely Teratosphaeria, Exophiala, Cladosporium, Penicillium, Aspergillus... (Complete abstract click electronic access below)

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The idiopathic dilated cardiomyopathy (IDC) is one of the major public health problems in the western world. Patients with IDC in functional class IV (New York Health Association - NYHA), even after therapeutic optimization, have high mortality. Stem cell therapy has emerged as a potential therapeutic option for cell death-related heart diseases and several positive effects were assigned to cell therapy in cardiomyopathy. The aim of this study was identify short-term result of cell transplantation in idiopathic dilated cardiomyopathy patients (IDC) who were treated by transplantation of autologous bone marrow mononuclear cells (BMMC). Intracoronary injections of autologous BMMC were performed in eight patients with severe ventricle dysfunction (mean of left ventricle ejection fraction – LEVF=20.03%), cardiac mass muscle around 156.2 g and NYHA between III and IV grades, other 8 IDC patients received placebo. The IDCs were followed - up for one and two years, by magnetic resonance imaging (MRI). The results after one year showed significant improvement in LVEF (mean=181.4) and muscle mass increasing (mean=181.4 g), after two years the LVEF continued improving, reaching a mean of 32.69% and the cardiac muscle mass kept stable (mean=179.4 g). Excepted for one patient, all the other had improvement in the NYHA functional class. The placebo group did not show any improvement. We believe that BMMC implant may be a beneficial therapeutic option for IDC patients.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The Spanish region of Campos de Hellin (Albacete) is characterized by a wide range of olive varieties (Arbequina, Benizal, Cornicabra, Cuquillo, Injerta, Manzanilla Local, Manzanilla de Sevilla, Negrilla, Picual), which provides different physicochemical and sensory characteristics to the oils. Thus, the knowledge of these characteristics may help develop more balanced oils. Monovarietal virgin olive oils from the different varieties grown in this area were characterized from the physicochemical and sensory points of view during four consecutive years. Clear differences among the varieties were found when principal component analysis was applied to the data from the studied parameters. The varieties were grouped according to their oleic and linoleic acid content, oxidative stability, and campesterol and total sterols content. The differences were significant with a 95% confidence level. The variety effect on the oil characteristics was stronger than the effect of the crop year. Practical applications: Chemical and sensory characteristics of monovarietal virgin olive oils play an important role in the elaboration of blends. In olive-growing regions where there is more than one variety cultivated, the characterization of monovarietal oils could increase the value of the olive oil produced due to the development of more balanced oils tailored to the preferences of consumers. This work shows that the chemical and sensory differences between varieties make possible the elaboration of a new range of virgin olive oils. This could encourage the development and marketing of quality oils, and thus increase the competitiveness of the mills in the oil market.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Spills can ocurr during oil productive chain and contaminate various environments due to the toxicity of monoaromatics hidrocarbons. Toluene stands out for being agressive to the nervous sistem and teratogenic, with high mobility and solubility in water, which facilitates environmental impact. Studies show that fungi are potential aromatic compounds assimilators, encouraging new researches about its use on the recovery of contaminated sites. This study aimed to select and characterize fungus with potential for biorremediation of toluene. 50 fungi were selected of the Collection of Microorganisms of Interest for Oil Gas and Biofuels, of UNESP Rio Claro, all of which were isolated from sites contaminated with monoaromatic hydrocarbons. Two trials were realized to select the microorganism with greater potential. The first test evaluated fungal growth under toluene saturated atmosphere. 24 fungi were chosen because its greater biomass production to participate in the next trial, the degradation in plates test, where the blue redox agente, DCPIP, indicates the degradation reaction, turning colorless. From this teste was possible to select one isolate which showed higher growth and stronger medium discoloration as the microorganism with the greatest potential to assimilate toluene. The Trichoderma cf. koningii had its potential evaluated through gas cromatography. The experiment proved the efficiency of the methodology, with positives results from the method validation and the effectiveness demonstrated of the LA-PHA-PACK bottles to prevent the volatilization of toluene during the 21 days of experiment. Being reliable its use for monitoring toluene decay associating it with degradation. This results are important because there aren't many methodologies and vials efficient to the purpose of this work. In the present study the degradation rates demonstrated no significant decay of the concentration of hydrocarbon. That may be related to the...

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A multicomponent reaction of β-naphthol, dimethyl malonate, and aromatic aldehydes in the presence of NbCl5 as promoter is described. Under similar conditions, aromatic aldehydes with different substituents exhibited different behaviors than β-naphthol and dimethyl malonate. In these MCRs, 4-aryl-3,4-dihydrobenzo[f]coumarins are obtained as the major products (41–93%) and 14-aryl-14H-dibenzo[a,j]xanthenes as the minor products (1–38%).

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Anacardium humile St. Hil. is being used in traditional medicine to treat ulcer. The present work evaluated the mechanisms of action involved in the anti-ulcer properties of the aqueous fraction from leaves of A. humile (AHQ). Gastroprotection of A. humile was evaluated in ethanol and piroxicam models. Mechanisms of action such as mucus production, nitric oxide (NO), sulfhydryl compounds (SH) and the anti-secretory action were evaluated. The acetic acid-induced gastric ulcer model was used to evaluate the A. humile healing properties. Results obtained in the ethanol model showed that AHQ provided significant gastroprotection at all the tested doses (50, 100, and 200 mg/kg). Thereby, the following protocols were performed using the dose capable of producing the most effective gastroprotection, which was the AHQ 200 mg/kg (P < 0.001). Moreover, AHQ (200 mg/kg) protected the mucosa from piroxicam-induced damage. Mucus, NO, and SH did not participate on this gastroprotection. AHQ interfere in H+ secretion in gastric mucosa, thus exerting an anti-secretory activity. Our results suggest that the gastroprotection and cicatrisation process executed by AHQ occurred due to its anti-secretory activity. This study reinforces its traditional medicinal use. Considering that the current therapies are based on the use of anti-secretory agents, the A. humile arises as a promising alternative antiulcer therapy.

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Pós-graduação em Química - IQ

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Pós-graduação em Química - IBILCE