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Macuchová, Simona. "Studium aktivity enzymových a nízkomolekulárních antioxidačních systémů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-233305.
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Oxidative processes play important role in cell physiology and pathology as well. Balance of these processes is supplied by cooperating antioxidative systems; function of antioxidant defense systems depens on high levels of antioxidants in organism. Presented work is focused on developement and optimization of methods for analysis of important enzyme and non-enzyme antioxidants as well as total antioxidant capacity of selected types of biological material. Extractions and analyses of vitamin E, carotenoids, superoxide dismutase, catalase, peroxidase and lipoxygenase in barley and malt were optimized. RP-HPLC and HPLC/ESI-MS were used for analysis of vitamin E, phenolic and carotenoid content, spectrophotometry was used for enzymes activity analysis. A new methods for catalase and lipoxygenase activities were developed and compared with direct UV methods. Superoxide dismutase activity was determined by commercial diagnostic kit. A colorimetric method was used for peroxidase activity determination. Some kinetic parameters of enzymes were provided too. Optimized methods were used in the analyses of antioxidants in plant material - in barley and malt - in sets of samples of 6 varieties cultivated in four different locations for two years. Content of individual antioxidants differed depending on the variety, but usually were not found significant differences in the levels, depending on growing location. Perhaps climatic conditions have the greatest influence on levels of low molecular weight and enzymatic antioxidants at the specific location; oxidation processes are influenced both the quantity of moisture, both by sunlight, which induces oxidative processes in cultivated plants. The activity of antioxidants in barley caryopses is rapidly increasing during the malting process; an elevated temperature and moistness first induces activation the enzyme systems including antioxidant. In caryopsis is metabolic activity increased during which we can expect an increased production of radicals; for this purpose can antioxidant systems be activated that protect cells from damage by oxidative stress. In the second part of work optimized methods were applied in two clinical trials focused on study of the influence of exogenous antioxidants intake on metabolic and antioxidant status in human organism. In the first clinical study influence of food supplement containing polyunsaturated fatty acids and vitamin E on metabolism of hyperlipidaemics was evaluated. After 3-month supplemenation a lipid profile was improved and serum antioxidant levels increased. The second experiment was focused on enzyme and non-enzyme antioxidant levels in healthy subjects after temporarily intake of specific foods rich in antioxidants. After two-month intake plasma phenolic substances were slightly increased. Total antioxidant capacity and activities of enzyme antioxidants were not affected. Results of both clinical exeriments showed that supplying of antioxidants in natural form or in the form of food supplements does not markedly affect metabolism of healthy subjects, while in patients with chronic diseases antioxidant supplementation can positively influence metabolic status. Results of this work showed that optimized methods are suitable for analyses of antioxidant status parameters and also for monitoring of exogenous antioxidant intake.
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Aucoin, Richard R. "Antioxidants and antioxidant enzymes as biochemical defenses against phototoxin ingestion by insect herbivores." Thesis, University of Ottawa (Canada), 1991. http://hdl.handle.net/10393/7679.
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Many secondary plant compounds are capable of photoactivation resulting in the production of toxic species of oxygen. One mechanism of defense for insects feeding on phototoxic plants may be the presence of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPOX), and glutathione reductase (GR). The activities of these enzymes were examined in larvae of three lepidoptera: Ostrinia nubilalis, Manduca sexta, and Anaitis plagiata. Highest levels of antioxidant enzyme activity were found in A. plagiata, a specialist feeder on Hypericum perforatum, which contains high levels of the phototoxin hypericin. Larvae of A. plagiata fed leaf discs treated with hypericin exhibited a short-term, concentration-dependent decline in enzyme activity. Longer term studies with A. plagiata fed either the phototoxic H. perforatum, or the closely related but non phototoxic H. calycinum, resulted in increased CAT and GR activity in larvae fed the phototoxic plant whereas superoxide dismutase activity was not significantly different. These results suggest that CAT and GR may be inducible defenses against phototoxins. Other insect defenses against phototoxins include specific biochemical defenses such as antioxidants. These antioxidant defenses eliminate or quench the deleterious singlet oxygen and free radicals formed by these phototoxins. We examined the role of dietary antioxidants in protecting the phototoxin-sensitive insect herbivore M. sexta. Elevated dietary levels of the lipid-soluble antioxidants beta-carotene and vitamin E resulted in a concentration-dependent reduction in the mortality associated with treatment of larvae with the phototoxic thiophene $\alpha$-T. Elevated levels of dietary ascorbic acid had no effect whereas reduced levels greatly increased the toxicity of $\alpha$-T. Tissue levels of antioxidants were shown to increase substantially in larvae fed antioxidant-supplemented diets. The results suggest that the ability to absorb and utilize plant-derived antioxidants could be an important defense against photo-activated plant secondary compounds and may have allowed some insects to exploit phototoxic plants. The effects of oxidative stress induced by $\alpha$-T at the biochemical level and the protective effect of antioxidants and antioxidant enzymes were also examined. The phototoxin $\alpha$-T strongly induced lipid peroxidation (LPO) in midgut tissues of the phototoxin-sensitive M. sexta in a UV-dependent manner, however this LPO was prevented when the compound was administered to larvae raised on high vitamin E diets. In the absence of UV, $\alpha$-T caused a significant increase in GPOX, GR, and non-GSH-dependent PER activity over 72 h. However in the presence of UV, $\alpha$-T strongly inhibited GPOX and GR and prevented the increase in PER. $\alpha$-T also affected cellular thiol status with approximately a 50% increase in total and GSH content in midgut tissue, although this was not UV-dependent. The effectiveness of antioxidant enzymes and the antioxidant GSH in providing protection against phototoxins were also examined. Neither the SOD inhibitor DEDC nor the CAT inhibitor 3AT affected the acute toxicity of topically applied $\alpha$-T to M. sexta larvae. The GSH-depleting agent BSO also had no effect on acute toxicity. In contrast, GSH depletion strongly enhanced the chronic (72 h) toxicity of $\alpha$-T when the phototoxin was incorporated into diets. GSH depletion also enhanced LPO in midgut tissue of $\alpha$-T-treated larvae. Implications of the results are discussed in terms of the role antioxidants and antioxidant enzymes may have played in the successful adaptation of some insect species to phototoxin-containing plants. The interrelationships of biochemical, physiological, physical, and behavioural mechanisms of defense are considered.
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Ferdová, Jitka. "Změny aktivit enzymů v ovoci v průběhu dlouhodobého uchovávání." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-216605.
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This study is focused on study of changes of enzyme and low-molecular weight antioxidants in different fruits during long-term storage. In theoretical part individual low-molecular weight antioxidants and enzymes are described. The main causes of fruit decay and some possibilities of fruit preservation and storage are summarized. As biological material some common fruits were chosen - green and red apples, peaches, plums and white grapes. The fruits were stored in laboratory, cellar, in refrigerator and in freezer. In freezing experiments some ways of fruit preparation and processing were tested and their influence on fruit antioxidant status was compared. Shortened storage experiment was applied on blueberries, cranberries, raspberries and strawberries too. In fruits some group parameters – total antioxidant status, dry mass content, ascorbate level, total flavonoids and total phenolics were analyzed spectrophotometrically. Individual flavonoids and phenolics were determined by RP-HPLC/UV-VIS and on-line LC/PDA/ESI-MS. Antioxidant enzyme activities (superoxide dismutase SOD, catalase CAT, polyphenol oxidase PPO and lipoxygenase LOX) were measured by spectrophotometry. The surface microscopy and cultivation of moulds from fruit surface were performed too. Influence of storage conditions on biological activities is dependent on fruit sort. Freezing is the most suitable procedure for long-term storage without significant changes of active substance content. Long-term storage in controlled temperature conditions and/or atmosphere is usable for fruits with longer storage period. In these fruits stabile levels of antioxidant enzymes are stored for relatively long time. Some of enzymes act synergistically. Enzyme activities differed according to storage phase; at the beginning mainly high SOD and LOX activities were observed. CAT and PPO are probably activated as defence systems in rippened and/or damaged fruits. Levels of total as well as individual low molecular weight antioxidants varied during storage in all sorts, generally, increased course with longer storage period can be observed.
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McElroy, Mary Catherine. "The role of antioxidant enzymes in human lung development." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293725.
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Järvinen, Kristiina. "Antioxidant enzymes and related mechanisms in malignant pleural mesothelioma." Helsinki : University of Helsinki, 2001. http://ethesis.helsinki.fi/julkaisut/laa/kliin/vk/jarvinen2/.
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Liu, Zheng-Xian. "Antioxidant activity of Mn-salophen complex and its effects on antioxidant enzymes in Escherichia coli." Diss., Virginia Tech, 1994. http://hdl.handle.net/10919/40046.
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Mn-salophen complex with superoxide-scavenging activity was prepared from manganese(III) acetate dihydrate and salophen in ethanol. Visible absorption spectrum of the red-brown solution exhibited a broad absorption band at 430 - 450 nm with two shoulders between 500 and 600 nm which were absent with either salophen or manganic acetate alone. Titration of salophen with manganese(III) was consistent with a 1:1 Mn to salophen stoichiometry of the complex based on changes in the absorbance at 500 nm or of superoxide scavenging activity. The SOD-like activity of the complex in the xanthine-xanthine oxidase/cytochrome c assay was 1450 units/mg salophen. The SOD activity of the complex was suppressed 50% in the presence of EDTA (1 mM), but was not altered in the presence of bovine serum albumin (1 mg/ml) or crude protein extract of E. coli QC779 sodA sodB (1 mg/ml). E. coli QC779 sodA sodB grew scantily after an 8 hour lag phase in aerobic M63 glucose minimal medium.Ph. D.
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Sabeh, Farideh. "Studies of the status of antioxidant enzymes and metabolites following burn injury, and the presence of antioxidant enzymes in the Aloe vera plant." Thesis, University of North Texas, 1995. https://digital.library.unt.edu/ark:/67531/metadc332708/.
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The effects of skin burn injury on the levels of oxidized and reduced glutthione, malondialdehyde, and on the activities of glutathione peroxidase, glutathione S-transferase, and glutathione reductase were determined in liver and lung of rabbit models, 24-h post-burn.
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Bonnineau, Chloé. "Contribution of antioxidant enzymes to toxicity assessment in fluvial biofilms." Doctoral thesis, Universitat de Girona, 2011. http://hdl.handle.net/10803/36688.
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Per tal d’avaluar l’impacte de la contaminació en els ecosistemes aquàtics, aquesta tesi es centra en una aproximació multi-biomarcador en els biofilms. En complement dels biomarcadors clàssics, es va demostrar que les activitats dels enzims antioxidants (AEA): catalasa, ascorbat peroxidasa i glutatió reductasa eren biomarcardors d'estrès oxidatiu en els biofilms. Tot i que les AEA poden veure's influenciades amb la mateixa mesura per factors naturals (edat del biofilm, llum de colonització o d'exposició) i contaminants (herbicides i farmacèutics), aquestes AEA permeten entendre millor l'efecte dels contaminants. Cal remarcar que assajos de toxicitat aguda es poden utilitzar per comparar la capacitat antioxidant entre comunitats i conèixer la seva pre-exposició a l'estrès oxidatiu. Aquesta aproximació multi-biomarcador a nivell de comunitat és especialment interessant per avaluar la toxicitat dels contaminants emergents (β-blockers) sobre espècies no-diana. Per tal de millorar-la, també es va verificar la possibilitat de mesurar l'expressió gènica en biofilms.To evaluate the impact of contamination on aquatic ecosystem, this thesis focused on a multi-biomarker approach, including molecular biomarkers, in biofilms. To complete the traditional tool-box of biofilm biomarkers, antioxidant enzymes activities (AEA) of catalase, ascorbate peroxidase and glutathione reductase were shown to be biomarkers of oxidative stress in biofilms. Though AEA can be influenced in the same extent by natural factors (biofilm age, colonization or exposure light) and toxicants (herbicides and pharmaceuticals), they provided valuable information to understand the chemicals effects. In particular, short-term toxicity tests are of interest to compare communities capacity to cope with oxidative stress and to know their exposure history to such stress. This multi-biomarker approach at community-level was found to be especially interesting to assess toxicity of emerging pollutants (β-blockers) on non-target communities. To improve this approach, the feasibility of measuring gene expression in biofilms using a functional gene array was also shown.
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Carville, David Gerald Michael. "The effect of copper status on blood antioxidant defence enzymes." Thesis, University of Ulster, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328211.
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Khanal, Akhileshwar. "Characterization of two antioxidant enzymes paraoxonase-1, and peroxiredoxin-6 /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 216 p, 2009. http://proquest.umi.com/pqdweb?did=1891601491&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Vicente, Silvio José Valadão. "Caracterização antioxidante do café (Coffea arabica, L.) e efeitos da sua administração oral em ratos." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/6/6133/tde-10092009-092017/.
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Introdução: Um dos fatores de risco para doenças crônicas não-transmissíveis é o excesso de espécies reativas causado pelo estresse oxidativo. Ácidos fenólicos atuam na defesa contra estas espécies, agindo como antioxidantes e como fatores de transcrição para as enzimas antioxidantes fase II (superóxido dismutase, catalase e glutationa peroxidase). Vários alimentos possuem ácidos fenólicos na composição porém o café se destaca pelo alto conteúdo dos mesmos e por ser consumido mundialmente. Objetivos: a) Comparar a capacidade antioxidante e a estabilidade dos cafés regular e descafeinado ao longo de seis meses; b) Verificar o tempo de resposta e possíveis correlações dose-resposta do efeito antioxidante em ratos após dose única de café; c) Avaliar o efeito antioxidante e possíveis danos hepáticos em ratos submetidos a doses repetidas de café durante 30 dias. Métodos: na etapa in vitro, foram analisados os compostos fenólicos totais, os principais ácidos fenólicos, a capacidade antioxidante (ORAC e DPPH) e a estabilidade destes parâmetros nos cafés regular e descafeinado durante seis meses. Na etapa in vivo, foram utilizados ratos machos Wistar, sendo dosadas as enzimas fase II e o ORAC, além do exame histopatológico e biomarcadores. Resultados: o café regular apresentou capacidade antioxidante inicial superior ao descafeinado com compostos fenólicos totais iguais e maiores teores de ácido fenólicos (15,3% cafêico, 17,0% p-cumárico e 38,1% ferúlico), ORAC (20,8%) e DPPH (3,9%). Após 6 meses, as amostras fechadas à vácuo praticamente não sofreram perdas, as abertas mantidas a 4oC apresentaram perdas medianas (9,6% fenólicos totais, 4,5-8,2% ácidos fenólicos, 21,3-21,6% ORAC e 2,8-3,2% DPPH) e as mantidas abertas a 20oC exibiram perdas elevadas (14,4-19,8% fenólicos totais, 11,9-19,6% ácidos fenólicos, 38,8-49,9% ORAC e 2,1- 3,8% DPPH). Após dose única de café para os ratos, o tempo de resposta máxima para as enzimas fase II e ORAC foi de 1 hora, com significância estatística para as enzimas (p=0,015 SOD e Cat, p=0,007 GPx e p=0,403 ORAC). Após diferentes doses, foram obtidas correlações dose-resposta positivas e com significância estatística para as enzimas (p=0,050 SOD, p=0,033 Cat, p=0,008 GPx e p=0,113 ORAC). Após doses repetidas (30 dias), a atividade das enzimas antioxidantes e o ORAC apresentaram grandes aumentos (74,8% SOD, 59,4% Cat, 135,2% GPx e 25,1% ORAC), todos estatisticamente significativos (p<0,001 para todos). O tecido hepático e os biomarcadores não apresentaram alterações em relação ao grupo controle. Conclusões: o café regular apresentou capacidade antioxidante superior ao descafeinado, os dois cafés não apresentaram perdas das características antioxidantes após seis meses se mantidos selados à vácuo e a administração oral de café regular aumentou a condição antioxidante dos ratos de maneira significativa, sem causar danos hepáticos.Introduction: A risk factor for several degenerative diseases is the excess of reactive species caused by oxidative stress. Phenolic acids share in the defense against those species, acting as antioxidants and as transcriptional factors for the phase II antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase). Several foods have phenolic acids in their composition but coffee stands out by the high contend of them and to be consumed worldwide. Objectives: a) Compare the antioxidant capacity and the stability of regular and decaffeinated coffees along six months; b) Verify the time of response and possible dose-response correlations of antioxidant effect in rats after a single dose of coffee; c) Evaluate the antioxidant effect and possible hepatic damages in rats submitted to repetitive doses along 30 days. Methods: in the in vitro step, it was analyzed the total phenolic compounds, main phenolic acids, antioxidant capacity (ORAC and DPPH) and the stability of these parameters in regular and decaffeinated coffees along six months. In the in vivo step, it was used male Wistar rats, being analyzed phase II enzymes and ORAC, besides histopathologic examination and biomarkers. Results: regular coffee presented a higher initial antioxidant capacity than decaffeinated coffee with equal total phenolic compounds and higher contend of phenolic acids (15.3% caffeic, 17.0% p-coumaric and 38.1% ferulic), ORAC (20.8%) and DPPH (3.9%). After six months, closed samples kept under vacuum practically did not show any losses, opened samples kept at 4oC presented regular losses (9.6% total phenolic compounds, 4.5-8.2% phenolic acids, 21.3-21.6% ORAC and 2.8-3.2% DPPH) and opened samples kept at 20oC exhibited big losses (14.4-19.8% total phenolic compounds, 11.9-19.6% phenolic acids, 38.8-49.9% ORAC and 2.1-3.8% DPPH). After a single dose of coffee for rats, time for maximum response of phase II enzymes and ORAC was 1 hour, with statistic significance for enzymes (p=0.015 SOD and Cat, p=0.007 GPx and p=0.403 ORAC). After different doses, it was obtained positive dose-response correlations, with statistic significance for enzymes (p=0.050 SOD, p=0.033 Cat, p=0.008 GPx and p=0.113 ORAC). After repetitive doses (30 days), the activity of antioxidant enzymes and ORAC showed big increases (74.8% SOD, 59.4% Cat, 135.2% GPx and 25.1% ORAC), all with statistic significance (p<0.001 for all). Hepatic tissue and biomarkers did not show any change compared to control group. Conclusions: regular coffee presented higher antioxidant capacity than decaffeinated coffee, both coffees did not show any antioxidant losses after six months if kept sealed under vacuum and the oral administration of regular coffee increased significantly the antioxidant condition of rats, without any hepatic damages.
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Souza, Jane Cristina de 1981. "Atividade antioxidante in vitro e in vivo de suco de uva e da norbixina." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256113.
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Orientador: Debora de Queiroz TavaresDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Estudos epidemiológicos demonstram que o consumo de dietas ricas em alimentos e bebidas de origem vegetal está associado à redução do desenvolvimento de doenças crônico-degenerativas. Tais alimentos são fontes de substâncias como carotenóides e polifenóis que podem atuar como agentes quimioprotetores, reduzindo os danos causados por espécies reativas de oxigênio, formadas tanto em condições fisiológicas quanto patológicas. Os objetivos do trabalho foram determinar in vivo a atividade antioxidante do suco de uva e da norbixina contra o estresse oxidativo provocado pela administração de Acetaminofeno (AAP), assim como determinar in vitro, a capacidade antioxidante dos sucos durante o processamento e estocagem. Foram dosados os teores de fenólicos totais pelo método de Folin-Ciocalteau, Catequinas e Epicatequinas por CLAE, principais componentes polares ativos por espectrometria de massa com ionização por electrospray com infusão direta (ESI-MS) e capacidade antioxidante pelo método do DPPH. Para determinação da atividade antioxidante in vivo foi conduzido um ensaio biológico com duração de 30 dias. Foram utilizados 30 ratos Wistar machos divididos em 6 grupos (n=5). Os animais ingeriram, duas vezes ao dia, 1 ml de suco de uva Concord (CGJ) (concentração de polifenóis 24mg/mL) ou 1 mL de solução aquosa de Norbixina (Nb) (concentração de 24mg/mL), ou 1 mL de água. Nos 29º e 30º dias os animais receberam intraperitonealmente uma dose de Acetaminofeno (100mg/kg de peso corpóreo). Após o sacrifício foram retirados fígado e rins para análises histológicas e enzimáticas. Os tecidos hepáticos e renais foram analisados por Microscopia Ótica (MO) e Eletrônica de transmissão (MET). Foram dosados os níveis de peroxidação lipídica (TBARS), a atividade das enzimas antioxidantes (SOD, MnSOD, CuZnSOD, GPx, GPx Se-dependente e catalase). Os resultados in vitro mostram que os sucos apresentam altos teores de fenólicos totais e capacidade antioxidante, os quais são mantidos durante o processamento e armazenamento do produto. Os resultados in vivo mostram que no fígado de animais tratados com CGJ+AAP e Nb+AAP houve diminuição significativa (p£0.05) da peroxidação lipídica induzida pelo AAP em 18.7% e 21.0% respectivamente. Por outro lado no rim, a redução foi de 7.1% no grupo CGJ+AAP e 5.3%, no grupo Nb+AAP, valores estes não diferentes (p£0.05) em comparação ao grupo AAP. Os níveis de peroxidação lipídica dos grupos que receberam Suco de uva Concord ou Norbixina, sem a presença de acetaminofeno, não diferiram do grupo Controle (p£0.05). O grupo CGJ+AAP mostrou um aumento significativo de 200% no fígado e de 100% nos rins na atividade de catalase em comparação ao grupo AAP. No grupo Nb+AAP a atividade de catalase aumentou 54% no fígado, enquanto que no rim, não ocorreu aumento na atividade de catalase em comparação ao grupo AAP. O estudo demonstra que os sucos analisados apresentam alta capacidade antioxidante a qual foi mantida durante as etapas de processamento e estocagem. Fígado e rins respondem de maneira distinta na presença de antioxidantes, porém ambos CGJ e Nb atenuam a toxicidade causada pelo AAP
Abstract: Epidemiological studies shown that the consumption of diets rich in plant foods and beverages is associated with reduction in the development of chronic-degenerative diseases. These foods are sources of substances such as carotenoids and polyphenols that can act as chemoprotectives agents, reducing the damage caused by reactive oxygen species, formed both in physiological and pathological conditions. The objectives of this study were to determine, in vivo, the antioxidant activity of grape juice and Norbixin against oxidative stress induced by Acetaminophen (AAP) administration, as well as determine, in vitro, the antioxidant capacity of juices during the processes of manufacturing and storage. Were determined the total phenolic contents using the Folin - Ciocalteau method; Catechin and Epicatechins by CLAE, major polar components by direct infusion and electrospray ionization mass spectrometry (ESI-MS) and antioxidant capacity by the DPPH method. To the antioxidant activity determination in vivo, was conducted a biological assay with 30 days of duration. They were used 30 rats male Wistar divided in 6 groups (n = 5). The animals were given twice daily 1 ml of Concord grape juice (CGJ) (polyphenols concentration 24mg/mL) or 1 mL of aqueous solution Norbixin (Nb) (concentration 24mg/ mL), or 1 mL of water. In 29 ° and 30 ° days, the animals received a dose of Acetaminophen (100mg/kg of body weight). After sacrifice, liver and kidneys were removed for histological and enzymatic analysis. The liver and kidney tissues were analyzed by optical microscopy (OM) and transmission electronic microscopy (TEM). Were measured lipid peroxidation levels (TBARS), the antioxidant enzymes activity (SOD, MnSOD, CuZnSOD, GPx, GPx Se-dependent and catalase). The in vitro results show that juices have high total phenolic levels and antioxidant capacity, which are kept for the processing and storage of these products. In vivo results show that liver of animals treated with CGJ+AAP and Nb+AAP was a decrease significant of lipid peroxidation caused by AAP in 18.7% and 20.99% respectively. On the other hand, in the kidney, the decrease was 7.1% in the CGJ+AAP group and 5.3% in the Nb+AAP group, whereas these values were not statistically different (p£0.05) compared to the group AAP. Concord grape juice or Norbixin tested alone did not differ from Control group. The CGJ+AAP group showed a significant increase of 200% in the liver and 100% in the kidneys in the catalase activity when compared to the AAP group. In Nb+AAP group catalase activity in the liver increased 54%, but in the kidney, there was no increase in activity of catalase compared to the group AAP. In this study was verified that juices showed high antioxidant capacity, which is maintained during the stages of processing and storage. Liver and kidneys showed distinct responses in the antioxidants presence, but both CGJ and Nb reduces AAP-toxicity induced
Mestrado
Nutrição Experimental e Aplicada à Tecnologia de Alimentos
Mestre em Alimentos e Nutrição
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Díaz, Albíter Héctor Manuel. "Reactive oxygen species and antioxidant enzymes in the Lutzomyia-Leishmania system." Thesis, University of Liverpool, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569775.
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Female phlebotomines are the vectors of Leishmania protozoa. Leishmania reside in the gut of the sand fly and they share this niche with different microbes that interact with either sand fly or Leishmania. Reactive Oxygen Species (ROS) are a major component of the insect innate immune system regulating gut-microbe homeostasis in other insects but the importance of this component in sand flies and its impact on Leishmania is unknown. The sand fly ROS system was initially investigated by examining the expression of antioxidant genes in the midgut of Lu. longipalpis throughout blood digestion using semi-quantitative RT-PCR. Antioxidant genes were differentially expressed throughout digestion and exhibited a peak at 48 h after blood feeding. Catalase was the most upregulated gene. Sand fly fecundity was affected by age and redox balance, as suggested by a significant reduction in egg numbers from older flies as well as after RNAi- mediated silencing of catalase. ROS detoxification appeared to be important during egg development as suggested by the accumulation of catalase in developing oocytes as well as an increase in egg numbers after antioxidant per os supplementation. Sand fly longevity was affected by redox balance, as shown by a significant reduction in survival after RNAi-mediated abrogation of catalase. Dietary addition of antioxidant failed to rescue early mortality, but this group also showed higher levels of phenoloxidase, a potential indicator of bacterial infection. Antioxidant genes were differentially expressed in Leishmania and Serratia colonised guts. Overall, midguts exhibited downregulation of ROS-detoxifying enzymes while Serratia-infected ones displayed the opposite trend. RNAi-silencing of catalase reduced Leishmania populations in the midgut suggesting that oxidative stress is deleterious to this protozoan. Dietary addition of the antioxidant uric acid in Serratia-infected flies increased sand fly mortality as in previous experiments with vitamin C. Although Serratia CFUs were significantly lower in the group with the highest mortality, the population of the resident microbiota was significantly higher in the same group. Interestingly, the numbers of resident microbiota were even higher in flies not infected with Serratia. The implications of the results are discussed in relation to gut immune homeostasis in other insect-microbe systems as well as the possibility of applying some of this information towards understanding the systems governing adult longevity in relation to vectorial capacity and the improvement of sand fly control.
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Zhang, Zhi Jun. "Investigation into membrane lipid peroxidation and antioxidant defence enzymes in schizophrenia." Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310764.
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Sadi, Gokhan. "Oxidative Damage And Regulation Of Antioxidant Enzymes In Streptozotocin Induced Diabetic Rats." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12611222/index.pdf.
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Increased oxidative stress and impaired antioxidant defense mechanisms are believed to be the important factors contributing to the pathogenesis and progression of diabetes mellitus. The products of lipid peroxidation and protein oxidation reactions were all found to be elevated significantly (p<0.05) in diabetic animals and supplementing the animals either individually or in combination, with two powerful antioxidants DL-&
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-lipoic acid (LA) and vitamin C (VC) brought this increment toward the control values. Considering Cu-Zn SOD, CAT and GST-Mu, there was a significant decrease in all activities in diabetic group as compared with control animals. RT-PCR and Western blot analysis results demonstrated that this decrease in activity is regulated at the level of gene expression, as both mRNA and protein expressions were also suppressed for these enzymes. However, in diabetic animals both the mRNA expressions and the activities of two other antioxidant enzymes, namely Mn SOD and GPx, did not change, indicating that the control of activities of these two enzymes were not at the level of genes. Supplementing the diabetic animals with VC increased all CAT, Cu-Zn SOD, GPx, and GST-Mu activities without changing both mRNA and protein expressions suggesting the possible role of post-translational modifications. On the other hand, the effect of VC on Mn SOD was observed at mRNA levels reflecting a transcriptional regulation. Furthermore, supplementing the animals with LA increased the CAT, Cu-Zn SOD, Mn SOD and GPx activities in diabetic rats but different from VC, LA also increased mRNA of CAT and protein levels of CAT, Cu-Zn SOD and Mn SOD suggesting both transcriptional and translational regulation showed by LA. Combined application of antioxidants also increased the CAT, Cu-Zn SOD, Mn SOD and GPx activities toward the control values, but this time there were no statistically significant change in their mRNA expressions even though protein amounts of both CAT and GPx were augmented. That is, when given together, these antioxidants exert their effects mainly at the level of protein synthesis. As a conclusion, diabetes and the resulting oxidative stress coordinately regulate the activities of the antioxidant enzymes at different regulatory points. LA and VC, two powerful antioxidants affect all antioxidant enzyme activities at different levels of transcription and translation. The results indicated the presence of very intricate control mechanisms regulating the activities of antioxidant enzymes in order to prevent the damaging effects of oxidative stress.
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Kalin, Cigdem. "Effects Of Acrylamide And Resveratrol On Rabbit Liver And Kidney Antioxidant Enzymes." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12611315/index.pdf.
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Resveratrol is one of the promising naturally occurring polyphenolic compound found in red wine having antioxidant and anti-carcinogenic properties. However, in vivo studies investigating the effects of resveratrol on antioxidant enzymes are limited. In the present study, we investigated, for the first time, the influence of resveratrol on liver and kidney antioxidant enzymes and oxidative stress markers in acrylamide treated and control rabbits.
New Zealand male rabbits were treated with acrylamide and resveratrol, separately in two different doses and conditions. Their combined effects were also investigated. While, acrylamide treatment significantly decreased the glutathione peroxidase (GPx) activity in liver (1.24-fold), it was significantly increased (1.20 &ndash1.40-fold) by combined effect of resveratrol and acrylamide in liver and kidney. Furthermore, alone resveratrol administration increased (~1.37 &ndash
fold) GPx activity in kidney. Although, glutathione reductase (GR) was found to be significantly increased (~1.30-fold) in two different dose of resveratrol treated rabbit liver, it was not changed in acrylamide and their combined treatments. Despite, glutathione (GSH) content was decreased around 1.6 fold as a result of acrylamide treatment in rabbit liver and kidney cytosols, GSH level was returned to normal levels by resveratrol tretment in rabbit liver and kidney. Furthermore, acrylamide treatment significantly increased the SDH activity in blood serum (1.68-fold) and in liver (1.27-fold) with respect to control. On the other hand, resveratrol treatment brought this activity nearly normal level in acrylamide treated rabbits.. Besides, sorbitol deydrogenase (SDH) was found to be decreased (3.13-fold) significantly in rabbit liver cytosol as a result of single dose of 100 mg/kg b.w. resveratrol treatment. Moreover, catalase activity and MDA level were not affected from either resveratrol or acrylamide and with their combination effect in investigated rabbit organs. An important liver damage marker enzyme other than ALT and AST, SDH was characterized in terms of substrate, cofactor and enzyme concentration in rabbits which have been not investigated before and found to be 200 mM, 141 µ
M and 0.5 µ
L, respectively in rabbit liver. Furthermore, the Km value was first calculated in liver of New Zealand rabbits as 55,5 mM. In addition to these, in vitro effects of resveratrol on GST activity was also studied throughout this study. Resveratrol was shown to be a noncompetitive inhibitor for liver cytosolic GST against substrate CDNB with Ki of 175 µ
M. On the other hand, resveratrol was shown to be a competitive inhibitor for liver cytosolic GST against substrate GSH with Ki of 55 µ
M. The results of the present study have demonstrated for the first time that resveratrol induced some of the antioxidant enzyme activities and as well nonenzymatic antioxidants in rabbit liver and kidney. The results of GPx, GR, SDH activities and GSH level have also suggested that resveratrol may have protective effects on acrylamide induced hepatoxicity and renal toxicity. Therefore, it may be a therapeutic approach for the oxidative stress-related diseases such as cancer. However, further in vivo studies are required to clarify the effect of resveratrol on both acrylamide-induced toxicity and bioavailability in the body.
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Matzilevich, David Avicenna. "Molecular analysis of superoxide dismutase and other antioxidant enzymes of Toxocara canis." Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266226.
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Reyazuddin, Mohammed [Verfasser]. "Oxidative Stress and the Level of Antioxidant Enzymes in Schizophrenia / Mohammed Reyazuddin." München : GRIN Verlag, 2020. http://d-nb.info/121583926X/34.
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Queiroz, Yara Severino de. "Efeito do processamento do alho (Allium sativum L.) sobre os seus compostos bioativos e potencial antioxidante in vitro e in vivo." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-24022011-113506/.
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Introdução: O aumento do consumo de frutas e hortaliças está associado à redução do risco de ocorrência de doenças crônicas não transmissíveis. Este efeito protetor tem sido atribuído particularmente à presença de vários compostos bioativos como compostos fenólicos e organosulfurados, além de fitosteróis presentes no alho que podem contribuir com os efeitos antioxidante e hipolipemiante. Porém, o processamento do alho pode acarretar mudanças na quantidade e na efetividade dos compostos bioativos. Este trabalho teve como objetivo avaliar se a cocção e a fritura do alho reduziram as concentrações de compostos bioativos, o potencial antioxidante in vitro e in vivo em hamsters hipercolesterolemizados. Métodos: In vitro - foram determinados nos alhos cru, frito e cozido: a) composição centesimal (proteínas, lipídios, cinzas, carboidratos, fibra alimentar solúvel e insolúvel); b) perfil de ácidos graxos; c) teor de fenólicos totais; d) teor de quercetina, miricetina e apigenina; e) fitosteróis; f) alicina; g) teor de cobre, zinco e selênio; h) produtos intermediários da reação de Maillard; i) potencial antioxidante utilizando os testes ORAC (Oxygen radical absorbance capacity), Rancimat® e o sistema -caroteno/ácido linoléico. In vivo - hamsters machos foram distribuidos em 5 grupos com 10 animais em cada grupo. 1 - controle; 2 - hipercolesterolêmico; 3- hipercolesterolêmico e alho cru; grupo 4 - hipercolesterolêmico e alho cozido; grupo 5 - hipercolesterolêmico e alho frito. Os animais foram eutanasiados após 4 semanas de estudo para análises do plasma e do tecido hepático. No plasma foi determinado o potencial antioxidante pelo teste ORAC, o perfil lipídico (colesterol total e frações e triacilgliceróis) e verificado a atividade das enzimas aspartato aminotransferase (AST) e alanina aminotransferase (ALT). No tecido hepático foram avaliadas a atividade das enzimas hepáticas (glutationa peroxidase, catalase e superóxido dismutase) e o potencial antioxidante utilizando dois métodos, ORAC e ensaio cometa. Resultados: In vitro - O teor de fibras totais para o alho cru foi de 10,0por cento (71,6por cento é solúvel e 28,4por cento é insolúvel). O alto conteúdo de ácidos graxos trans no alho frito (14,9por cento ) é devido ao processo de fritura com 50por cento de gordura vegetal hidrogenada. A cocção não alterou o teor dos minerais analisados. O teor de compostos fenólicos nas amostras de alho variou de 4,2 a 187,7 mg EAG/100g (base seca), dependendo do solvente (água, água/metanol, etanol ou acetona) e do método de extração utilizados. A fritura diminuiu os teores de quercetina e alicina em torno de 24por cento e 87por cento , respectivamente. Os fitosteróis -sitosterol e campesterol estão presentes em todas as amostras, sendo que o alho frito apresentou os maiores teores destes compostos em relação aos alhos cru e cozido, além de apresentar stigmasterol. A fritura foi o processamento térmico que contribuiu com os maiores valores de produtos intermediários da reação de Maillard. O potencial antioxidante pelo teste ORAC (extratos etanólicos, metanol/água e acetona) reduziu com o processamento do alho, sendo que a redução foi maior para a fritura. A inibição da oxidação lipídica foi melhor nos extratos metanol/água. In vivo - O grupo de animais que recebeu ração hiperlipemiante e alho cru teve menor ganho de peso em relação aos grupos que receberam alho frito ou cozido. Os alhos cru e cozido foram eficazes na redução de lipídios no plasma dos hamsters. O potencial antioxidante, avaliado pelos testes ORAC e ensaio cometa, dos grupos hipercolesterolemizados suplementados com alho cru ou cozido apresentaram valores superiores em relação ao grupo hipercolesterolemizado não suplementado. Houve aumento da atividade das enzimas antioxidantes catalase, glutationa peroxidase e superóxido dismutase para todos os grupos suplementados com alho. Em todos os grupos estudados não ocorreram danos estruturais ou funcionais no tecido hepático. Conclusões: Os resultados corroboram com o esperado e sugerem que os alhos cru e cozido podem ocasionar benefícios à saúde, haja vista que estes produtos possuem compostos bioativos, efeito hipolipemiante e apresentaram alto potencial antioxidante no plasma e no tecido hepático, além do aumento da atividade de enzimas antioxidantes que estão envolvidas em mecanimos de proteção à saúdeIntroduction: The increased consumption of fruits and vegetables is associated with reduced risks of chronic diseases. This protective effect has been attributed particularly to the presence of several bioactive compounds such as phenolic and organosulfur compounds, likewise phytosterols present in garlic that may contribute to the antioxidant and lipid-lowering effects. However, the processing of garlic can cause changes in the quantity and effectiveness of bioactive compounds. This study aimed to evaluate whether the cooking and frying of garlic reduced the bioactive compounds concentrations, the antioxidant potential in vitro and in vivo in hypercholesterolemic hamsters. Methods: In vitro - were determined in raw garlic, fried and boiling: a) composition (protein, fat, ash, carbohydrates, dietary fiber, soluble and insoluble), b) fatty acid profile, c) total phenolic content, d ) content of quercetin, myricetin and apigenin, e) phytosterols, f) allicin, g) content of copper, zinc and selenium, h) Maillard reaction products, i) antioxidant potential using the ORAC test (Oxygen radical absorbance capacity), Rancimat® and system -caroteno/ácido linoleic. In vivo - male hamsters were divided into five groups with 10 animals each. 1 - control, 2 hypercholesterolemic, 3 - hypercholesterolemic and raw garlic, 4 - hypercholesterolemic and boiling garlic, group 5 - hypercholesterolemic and fried garlic. Samples of blood and liver were collected after a 4-week experimental period. In plasma were determined the antioxidant potential by the ORAC assay, the lipid profile (total cholesterol and fractions and triacylglycerols) and verified the activity of enzymes aspartate aminotransferase (AST) and alanine aminotransferase (ALT). In liver tissue were evaluated the activity of liver enzymes (glutathione peroxidase, catalase and superoxide dismutase) and the antioxidant potential using two methods, ORAC and comet assay. Results: In vitro - The content of dietary fiber for raw garlic was 10.0per cent (71.6per cent is soluble and 28.4per cent is insoluble). The high content of trans fatty acids in fried garlic (14.9per cent ) is due to the frying process with 50per cent hydrogenated vegetable fat. The cooking did not alter the content of the minerals analyzed. The content of phenolic compounds in garlic samples ranged from 4.2 to 187.7 mg EAG/100g (dry matter), depending on the solvent (water, water / methanol, ethanol or acetone) and the extraction method used. Frying decreased the content of quercetin and allicin around 24per cent and 87per cent respectively. The phytosterols -sitosterol and campesterol are present in all samples, and the fried garlic showed the highest levels of these compounds in relation to raw and boiling garlic, besides presenting stigmasterol. Frying was the heat processing that contributed to the higher values of products of the Maillard reaction. The antioxidant potential by the ORAC assay (ethanol extracts, methanol/water and acetone) was reduced with the processing of garlic, and the reduction was greater for frying. The inhibition of lipid oxidation was better in methanol/water extracts. In vivo - The group of animals that received ration hyperlipidemic and raw garlic had less weight gain compared with groups that received garlic fried or boiling. Raw and boiling garlic were effective in reducing lipids in hamsters plasma. The antioxidant potential (measured by the ORAC and comet assay tests) of the groups hypercholesterolemic supplemented with raw or boiling garlic had higher values than the not supplemented group hypercholesterolemic. There was increased activity of antioxidant enzymes catalase, glutathione peroxidase and superoxide dismutase in all groups supplemented with garlic. In all groups there was no structural or functional damage in liver tissue. Conclusions: These results corroborate the expected and suggest that the raw and boiling garlic may lead to health benefits, given that these products have bioactive compounds, hypolipidemic effect and showed a high antioxidant potential in plasma and liver tissue, in addition to increased activity of antioxidant enzymes that are involved in mechanisms of health protection
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Toye, Ashley Mark. "An investigation of the effects of amyloid beta peptide on human neuronal cells : generation of oxidative stress." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266876.
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Lakari, E. (Essi). "Expression of oxidant and antioxidant enzymes in human lung and interstitial lung diseases." Doctoral thesis, University of Oulu, 2002. http://urn.fi/urn:isbn:9514266625.
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Abstract
Antioxidants function as blockers of radical processes and eliminate harmful reactive oxygen species (ROS) produced during normal cellular metabolism. A complex antioxidant defence system has evolved to protect the cellular homeostasis. This system includes antioxidant enzymes (AOEs), such as superoxide dismutases (SODs), which are intracellular MnSOD and CuZnSOD and extracellular ECSOD, H2O2 scavenging enzymes catalase and glutathione peroxidase, and hemeoxygenase-1 (HO-1), an important enzyme in heme metabolism, which has also been suggested to have antioxidant capacities. ROS play an important role in the pathogenesis of interstitial lung diseases. These diseases represent a group of disorders with different etiology, histopathology, treatment and prognosis. Sarcoidosis, extrinsic allergic alveolitis and two different forms of idiopathic pulmonary fibrosis, usual interstitial pneumonia (UIP) and desquamative interstitial pneumonia (DIP) were included in this study.
The purpose of this research was to evaluate the expressions of inducible nitric oxide synthase (i-NOS), endothelial nitric oxide synthase (e-NOS) and xanthine oxidase (XAO), oxidant generating enzymes commonly associated with tissue injury, and, on the other hand, the expressions of AOEs suggested to be involved in the defence of lung tissue against oxidant stress. The methods included immunohistochemistry on lung biopsies (n=48) and Western blotting, Northern blotting or reverse polymerase chain reaction (RT-PCR) on human inflammatory cells and cells obtained from bronchoalveolar lavage. I-NOS was intensively expressed in inflammatory, but not in fibrotic lesions, similar e-NOS expression was found in control lung and in all interstitial lung diseases, while XAO was mainly negative. MnSOD and HO-1 were highly expressed in the granulomas of sarcoidosis. In contrast the expressions of MnSOD and HO-1 in late fibrotic lesions of UIP were low or undetectable by immunohistochemistry. CuZnSOD and catalase showed similar immunoreactivity in healthy and diseased lung. A cell specific expression and regulation of various enzymes may play an important role during acute inflammatory diseases and also in the progression of lung fibrogenesis.
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Li, Timao. "Early changes in myocardial antioxidant enzymes due to adriamycin and modulation by probucol." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0019/NQ53063.pdf.
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Lepp, Dion. "The regulation of manganese superoxide dismutase and other antioxidant enzymes in Drosophila melanogaster." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0027/MQ51073.pdf.
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Rosette, Jessica. "Sex differences in total and specific antioxidant enzymes in unirradiated and irradiated skin." Connect to resource, 2008. http://hdl.handle.net/1811/32158.
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Sigfrid, Louise Anna Jenny. "Regulation of antioxidant enzymes by cytokines or nitric oxide in insulin-containing cells." Thesis, University of Brighton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246826.
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Gamble, Simon Charles. "Regulation and function of glutathione peroxidase and related antioxidant enzymes in marine invertebrates." Thesis, University of Surrey, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308490.
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Barros, Aline Oliveira. "Avaliação das atividade antioxidantes e inibitória sobre enzimas elastase e colagenase e hialuronidase da libidibia ferrea MART." Universidade Federal do Amazonas, 2012. http://tede.ufam.edu.br/handle/tede/4085.
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The skin is the largest organ in the human body and is intended to serve as a barrier against external agents. The loss of integrity of this tissue can cause injury or illness that can lead to death. The aging of the skin, which is also a natural process of the body, has its root causes and can be accelerated due to extrinsic causes, such as exposure to solar radiation, which causes physical changes to the skin, due to changes that occur in the connective tissue through the formation of lipid peroxides, contents of cells and enzymes and reactive oxygen species. Due to the important role in tissue remodeling processes in health and disease involving the skin, some studies have shown investigations with plant extracts as inhibitors of enzymes and antioxidants. The Libidibia ferrea Mart. is a tree that belongs to the family Leguminosae-Caesalpininoideae which grows in Brazil widely distributed in North and Northeast, especially in Pernambuco and Ceará. The species is popularly known as “jucá”, “pau-ferro”, “ibirá-obi”, “imirá-itá”, “muirá-obi”, “muiré-itá”. The phytochemical investigation of the hydroalcoholic extract of L. ferrea revealed the presence of flavonoids, saponins, tannins, curmarinas, steroids and other phenolic compounds, classes of substances already mentioned in the literature as potential antioxidants and enzyme inhibitors. We used extracts from the bark and pods of L. ferrea in different concentrations to perform the tests anti-elastase, anti-collagenase, anti-hyaluronidase test and in vitro antioxidant and in NIH3T3 murine fibroblast cells. The anti-elastase test, the skin showed inhibition constant average of 42% at concentrations of 63 μg / mL to 1000 μg / mL. In assessing the inhibitory activity of collagenase, it was found that the bark extract of L. ferrea showed no significant activity at the concentrations tested (25, 50 and 100 μg / mL), and inhibition of 15.2%. At the highest concentration tested (100 μg / mL) extract produced from the pod L. ferrea showed greater inhibition of enzyme activity compared with the extract made from the bark. Although the extracts of bark and pods of L. ferrea have been shown to be good scavengers of DPPH radicals in vitro test, the test cell with fibroblasts NIT3T3, extracts, in concentrations non-toxic, have not been able to capture radicals significantly. These results demonstrate that extracts of L. ferrea can be considered promising in studies on aging and skin diseases.
A pele é o maior órgão do organismo humano e tem finalidade de servir como barreira contra agentes externos. A perda da integridade deste tecido pode causar lesões ou doenças que podem levar a morte. O envelhecimento da pele, que também é um processo natural do organismo, tem suas causas intrínsecas e pode ser acelerado devido a causas extrínsecas, como a exposição à radiação solar, que provoca mudanças físicas para a pele, devido a alterações que ocorrem no tecido conjuntivo através da formação de peróxidos lipídicos, conteúdo das células e enzimas e espécies reativas de oxigênio. Devido ao papel importante na remodelação tecidual nos processos que envolvem saúde e doença da pele, alguns estudos tem mostrado investigações com extratos de plantas como inibidores de enzimas e antioxidantes. A Libidibia ferrea Mart. é uma árvore que pertence à família Leguminosae-Caesalpininoideae e que cresce em todo o Brasil largamente distribuída nas regiões Norte e Nordeste, principalmente em Pernambuco e no Ceará. A espécie é conhecida popularmente como jucá, pau-ferro, ibirá-obi, imirá-itá, muirá-obi, muiré-itáe. A investigação fitoquímica do extrato hidroalcoólico das cascas e folhas de L. ferrea revelou a presença de flavonóides, saponinas, taninos, curmarinas, esteróides e outros compostos fenólicos, classes de substâncias já citadas na literatura como potenciais antioxidantes e inibidores de enzimas. Foram utilizados extratos da casca e vagem de L. ferrea em diferentes concentrações para realizar os testes anti-elastase, anti-colagenase, anti-hialuronidase e teste antioxidante in vitro e em células de fibroblastos murinos NIH3T3. O teste anti-elastase, a casca mostrou inibição média constante de 42% nas concentrações de 63 μg/mL até 1000 μg/mL. Na avaliação da atividade inibitória da colagenase, verificou-se que o extrato da casca de L. ferrea não apresentou atividade importante nas concentrações testadas (25, 50 e 100 μg/mL), sendo a inibição de 15,2%. Na maior concentração testada (100 μg/mL). o extrato produzido a partir da vagem de L. ferrea apresentou maior inibição da atividade enzimática quando comparado com o extrato feito a partir da casca. Apesar dos extratos da casca e vagem de L. ferrea terem se mostrado bons varredores de radicais de DPPH no teste in vitro, no teste celular com fibroblastos NIT3T3, os extratos, em concentrações não tóxicas, não foram capazes de captar radicais de maneira significativa. Estes resultados demonstram que os extratos de L. ferrea podem ser considerados promissores nos estudos referentes a antienvelhecimento e doenças da pele.
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Govinda, Rao Yelagalawadi S. Richardson Arlan. "Effect of aging and diet on the expression of antioxidant enzymes in male Fischer F344 rats." Normal, Ill. Illinois State University, 1989. http://wwwlib.umi.com/cr/ilstu/preview?9014746.
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Thesis (Ph. D.)--Illinois State University, 1989.Title from title page screen, viewed October 24, 2005. Dissertation Committee: Arlan Richardson (chair), David Borst, Herman E. Brockman, H. Tak Cheung, Lynne A. Lucher. Includes bibliographical references (leaves 112-128) and abstract. Also available in print.
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Ramos, Nádia da Silva. "Alterações fisiológicas e bioquímicas de mudas de Acacia Mangium à aplicações de doses de glyphosate." Universidade Federal do Tocantins, 2017. http://hdl.handle.net/11612/499.
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O glyphosate é um dos herbicidas mais utilizados no mundo, pelo seu amplo espectro de ação, em espécies arbóreas, entretanto, pouco se sabe sobre a sua atuação nessas espécies. O objetivo desta pesquisa foi avaliar as alterações fisiológicas, bioquímicas e morfológicas do glyphosate em Acacia mangium. O experimento foi realizado em condições de campo. As plantas jovens de Acacia Mangium receberam 5 tratamentos correspondentes a doses do herbicida (0, 180, 360, 540 e 720 g.e.a.L-1 de glyphosate) em 6 repetições. No primeiro experimento,foi avaliado o crescimento e aspectos fisiológicos das plantas sob estresse oxidativo. Onde foram avaliadas as variáveis: Incremento em diâmetro, incremento em altura, massa seca do caule, folhas e raiz, intoxicação e também a assimilação líquida de carbono, condutância estomática, transpiração, eficiência do uso da água e eficiência da rubisco. No segundo experimento, avaliou-se as alterações bioquímicas em plantas jovens de Acacia mangium, sob estresse oxidativo. Para tanto, foi avaliado a atividade das enzimas antioxidantes: Ascorbato de peroxidase e superoxido dismutase. O glyphosate afeta a Acacia a partir da dose de 360 g.e.a.L-1 tanto fisiologicamente quanto morfologicamente. Os incrementos foram reduzindo de acordo com o aumento das doses. Em relação a assimilação líquida, as doses de 540 e 720 g.e.a.L-1 foram reduzidas aos 6, 12,18 DAA, se estabilizando a partir dos 24 dias de avaliação. As respostas das enzimas oxidativas ao estresse oxidativo foram variáveis. A enzima superóxido dismutase (SOD) apresentou um aumento na dose de 180 g.e.a.L-1 havendo decréscimo com o aumento das concentrações testadas. Para a Ascorbato de peroxidase (APX), mantiveram atividade semelhante nas duas avaliações, com um aumento continuo de acordo com o aumento das doses.Glyphosate is one of the most widely used herbicides in the world due to its broad spectrum of action on tree species, but little is known about its performance in these species. The objective of this research was to evaluate the physiological, biochemical and morphological alterations of glyphosate in Acacia mangium. The experiment was carried out under field conditions. The young plants of Acacia Mangium received 5 treatments corresponding to doses of the herbicide (0, 180, 360, 540 and 720 g.e.a.L-1 of glyphosate) in 6 replicates. In the first experiment, the growth and physiological aspects of the plants under oxidative stress were evaluated. The following variables were evaluated: increase in diameter, height increase, stem dry mass, leaves and root, intoxication and also net carbon assimilation, stomatal conductance, transpiration, water use efficiency and rubisco efficiency. In the second experiment, the biochemical alterations were evaluated in young plants of Acacia mangium, under oxidative stress. For that, the activity of the antioxidant enzymes: peroxidase ascorbate and superoxide dismutase was evaluated. Glyphosate affects Acacia from the 360 g.e.a.L-1 dose both physiologically and morphologically. The increments were reduced as the doses increased. Regarding the net assimilation, the doses of 540 and 720 g.e.a.L-1 were reduced to 6, 12,18 DAA, stabilizing from the 24 days of evaluation. The responses of oxidative enzymes to oxidative stress were variable. The enzyme superoxide dismutase (SOD) showed a dose increase of 180 g.e.a.L-1, decreasing with increasing concentrations tested. For the peroxidase Ascorbate (APX), they maintained similar activity in both evaluations, with a continuous increase according to the increase of the doses.
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Martins, Carolina de Aguiar. "Avaliação da atividade antioxidante in vitro e in vivo do guaraná (Paullinia cupana) em pó." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-31012011-093906/.
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Introdução Estudos indicam que antioxidantes presentes naturalmente em alguns alimentos são capazes de atuar como protetores dos organismos vivos frente aos danos causados pelo estresse oxidativo em macromoléculas como lipídios, proteínas e em DNA. O guaraná (Paullinia cupana), planta originária da Amazônia, contém elevadas concentrações de taninos e cafeína, compostos com comprovada atividade antioxidante. Apesar do aumento no consumo de guaraná e de estudos associando seus efeitos benéficos à saúde, há poucas informações sobre suas propriedades antioxidantes in vivo. Objetivos: avaliar o efeito do consumo de bebida a base guaraná em pó em humanos. Métodos - In vitro: amostras de guaraná em pó foram analisadas para determinação da composição proximal; conteúdo de compostos fenólicos totais (Folin-Ciocalteau) e atividade antioxidante pelo ensaio DPPH foram determinados em amostras extraídas com água, metanol, etanol 60 por cento e acetona 35 por cento. In vivo e ex vivo: amostras de sangue de voluntários saudáveis (n=12) foram coletadas em jejum (J1) e 1h após o consumo da bebida com guaraná em pó foram coletadas novamente amostrar de sangue (G1). Após 15 dias da ingestão diária da bebida foram realizadas duas novas coletas, uma em jejum (J15) e outra após a primeira hora de consumo da bebida (G15). Foi avaliada a resistência da LDL à oxidação ex vivo iniciada com cobre pelo ensaio de dienos conjugados. O perfil antioxidante total (TAS) e a capacidade de absorbância de radical oxigênio (ORAC) foram determinados no plasma dos voluntários. Ensaio Cometa foi realizado para verificar danos oxidativos ao DNA em linfócitos dos voluntários. A atividade das enzimas Superóxido Dismutase (SOD), Catalase (Cat) e Glutationa Peroxidase (GPx) foi determinada em eritrócitos. Os resultados das diferentes análises foram apresentados com média e desvio-padrão. Foram utilizados ANOVA e teste de Tukey para verificar se há diferença no teor de compostos fenólicos totais e na atividade antioxidante das amostras extraídas com diferentes solventes. As verificações de aderência à curva normal foram realizadas pelo teste de KolmogorovSmirnov. As comparações das variáveis de distribuição normal para as amostras pareadas foram baseadas no teste t de Student. Para todas as inferências foi utilizado o nível de significância menor ou igual a 5 por cento. Para todos estes cálculos estatísticos foi utilizado o programa SPSS versão 16.0 for Windows. Resultados: Foi observado aumento significativo no lag time de oxidação da LDL tanto após uma hora do consumo da primeira dose de guaraná em pó quanto após uma hora do consumo no 15º dia de intervenção (G1>J1, G15>J15; p<0,05). O consumo de uma única dose de guaraná aumentou significativamente a atividade da Cat nos tempos G1 e G15 (p < 0,05) e da GPx no tempo G15 (p<0,05). Após intervenção com doses repetidas durante 15 dias houve aumento significativo da atividade da Cat e da GPx no jejum do último dia de intervenção quando comparado ao jejum do baseline (J15>J1; p<0,05). O consumo de guaraná não influenciou a atividade da SOD, tampouco o TAS (p>0,05). O consumo da bebida apresentou efeito agudo sobre o ORAC, uma vez que houve aumento significativo desse parâmetro tanto após uma hora do consumo da primeira dose de guaraná em pó quanto após uma hora do consumo no 15º dia de intervenção (G1>J1, G15>J15; p<0,05). O ORAC no plasma dos voluntários e avaliação de danos oxidativos ao DNA com desafio por peróxido de hidrogênio apresentaram o mesmo comportamento da resistência da LDL à oxidação: apenas efeito agudo foi observado pelo consumo da bebida (G1>J1, G15>J15; p<0,05). Sugere-se que o fracionamento da dose de guaraná em pó seja mais eficiente do que o consumo de uma única dose no dia para a manutenção da concentração dos compostos fenólicos no plasma a fim de promover efeitos pelo consumo de doses repetidas. Os efeitos antioxidantes pelo consumo de uma única dose de guaraná em pó parecem se extender além do tempo de depuração dos compostos fenólicos no plasma. São necessárias ainda novas pesquisas a fim de avaliar a dose e o tempo de intervenção para que sejam observados efeitos em humanos pela ingestão de doses repetidas de guaranáIntroduction Studies indicate that antioxidants found naturally in some foods are capable of acting as protectors of living organisms against oxidative stress in macromolecules such as lipids and proteins and in DNA. Guarana (Paullinia cupana), a plant from Amazonia, contains high concentrations of tannins and caffeine, compounds with proven antioxidant activity. Despite the increase in consumption of guarana and studies linking their beneficial health effects, there is little information on its antioxidant properties in vivo. Objectives: investigate the effects of guarana consumption in humans. Methods: In vitro: guarana powder samples were analyzed for proximal composition; content of total phenolics (Folin- Ciocalteau) and antioxidant activity by DPPH assay were determined in samples extracted with water, methanol, ethanol 60 per cent and acetone 35 per cent. In vivo and ex vivo: blood samples from healthy volunteers (n = 12) were collected at a twelve-hour overnight fast (J1) and 1h after consumption of the drink with guarana powder the second blood sample was collected (G1). After 15 days of daily ingestion of the drink other two samples were collected: a twelve-hour overnight fast (J15) and again after the first hour of drink consumption (G15). The resistance of LDL to ex vivo oxidation initiated by copper was evaluated. The total antioxidant status (TAS) and the oxygen radical absorbance capacity (ORAC) were determined in plasma of volunteers. Comet assay was conducted to determine oxidative DNA damage in lymphocytes of volunteers. The activity of superoxide dismutase (SOD), catalase (Cat) and glutathione peroxidase (GPx) was determined in erythrocytes. ANOVA and test of Tukey were used to verify if there was significant differences in total phenolic contents and antioxidant activity of samples extracted with different solvents. The verification of adherence to the normal curve were performed by the Kolmogorov-Smirnov test. Comparisons of variables of normal distribution for the paired samples were based on t test of Student. For all inferences the significance level was less than or equal to 5 per cent. For all these calculations the statistical program SPSS version 16.0 for Windows was used. Results: Significant increase in lag time of LDL oxidation was observed, both after one hour of consumption of the first dose of guarana powder and after one hour of consumption in the 15th day of intervention (G1> J1, G15> J15, p <0.05). The consumption of a single dose of guarana significantly increased the activity of Cat in the times G1 and G15 (p<0.05). After intervention with repeated doses during 15 days, there was a significantly increase in the activity of Cat and GPx in fasting of the last day intervention compared to baseline fasting (J15> J1, p<0.05). The consumption of guarana didnt influence the activity of SOD neither the TAS (p>0.05). The ORAC in plasma of volunteers and assessment of oxidative damage to DNA challenge with hydrogen peroxide showed the same behavior of the resistance of LDL to oxidation: only acute effect was observed by the consumption of the drink (G1> J1, G15> J15, p<0.05). It is suggested that the fractionation of the dose of guarana powder is more efficient than the consumption of a single dose on day to maintain the concentration of phenolic compounds in plasma to promote the consumption effects of repeated doses. The antioxidant effects by consumption of a single dose of guarana powder seem to extend beyond the time of clearance of phenolic compounds in plasma. New reserches are needed in order to evaluate the dose and duration of intervention for being observed effects in humans by ingestion of repeated doses of guarana
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Oliveira, Luciana de Siqueira. "Evaluation of antioxidant metabolism during development of acerola and sapodilla clones." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7570.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorFruit ripening is a complex developmental process involving changes in biochemical, physiological and sensorial characteristics as well as in the oxidative metabolism which result in their quality attributes and antioxidant properties This research described the major changes in the antioxidant systems during development of two tropical fruit species Acerola (Malpighia emarginata D.C) and sapodilla (Manilkara zapota L.) fruits were analyzed at different maturity stages for quality parameters post-harvest antioxidant compounds total antioxidant activity (TAA) antioxidant enzymes activity and cell membrane integrity Ripening process promoted improvements in post-harvest quality of tropical fruits studied In acerola the total vitamin C and total soluble phenols (TSP) content reduced during development which resulted in decline of total antioxidant activity (TAA) In spite of the decline in TSP the yellow flavonoid and total anthocyanins content showed an evident increase at ripening which may be associated to fruit coloring and antioxidant nutrition properties While in sapodilla antioxidant compounds contents reduced significantly during the fruit development which contributed to decreased of TAA that resulting mainly from the decline of phenolics contents such as TSP and yellow flavonoids because sapodilla is not a good vitamin C source The activities of oxygen-scavenging enzymes superoxide dismutase (SOD) catalase (CAT) and ascorbate peroxidise (APX) decreased with tropical fruits ripening which contributed to an increased oxidative stress as evidenced by lipid peroxidation therefore necessary to make easy many changes related to aging The development of tropical fruits studied was accompanied by progressive increase in oxidative and peroxidative stress which can contributed to the fruit postharvest quality and nutritional antioxidant potential
O amadurecimento de frutos à um processo complexo do desenvolvimento envolvendo inÃmeras mudanÃas nas caracterÃsticas bioquÃmicas, fisiolÃgicas e sensoriais bem como no metabolismo oxidativo determinando seus atributos de qualidade e propriedade antioxidante Desta forma esse trabalho objetivou analisar as principais mudanÃas no sistema antioxidante durante o desenvolvimento de frutos de duas espÃcies tropicais Os frutos de aceroleira (Malpighia emarginata D.C) clones II 47/1 BRS 235 BRS 236 BRS 237 e BRS 238 e de sapotizeiro (Manilkara zapota L.) clones BRS 227 e BRS 228, foram analisados em diferentes estÃdios do desenvolvimento quanto Ãs variÃveis de qualidade pÃs-colheita compostos antioxidantes atividade antioxidante total (AAT) atividade das enzimas antioxidante e grau de peroxidaÃÃo de lipÃdeos. Durante o processo de desenvolvimento das acerolas o conteÃdo de vitamina C e de polifenÃis solÃveis totais (PST) diminuiu resultando em um declÃnio da atividade antioxidante dos frutos Apesar da reduÃÃo dos PST o conteÃdo de flavonÃides amarelos e antocianinas totais mostraram um aumento evidente com o amadurecimento o que pode estar associado à mudanÃa de cor e propriedades antioxidantes nutricionais da acerola Enquanto no sapoti o conteÃdo dos compostos antioxidantes diminuiu significativamente ao longo do desenvolvimento contribuindo para uma reduÃÃo da AAT resultante principalmente do declÃnio do conteÃdo dos fenÃlicos flavonÃides amarelos e polifenÃis totais pois o sapoti nÃo à considerado uma boa fonte de vitamina C A atividade das enzimas antioxidantes dismutase do superÃxido (SOD) catalase (CAT) e peroxidase do ascorbato (APX) diminuiu ao longo do amadurecimento dos frutos tropicais estudados o que contribuiu para um aumento do estresse oxidativo evidenciado pelo aumento da peroxidaÃÃo de lipÃdeos sendo, portanto necessÃrio para facilitar muitas das mudanÃas relacionadas com a maturaÃÃo O amadurecimento das espÃcies tropicais estudadas foi acompanhado por um aumento do estresse oxidativo e peroxidativo o qual pode contribuir para as alteraÃÃes observadas na qualidade pÃs-colheita dos frutos e para um declÃnio em seu potencial antioxidante
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Ferreira, Thalita Montoril. "Biochemical and physiological responses of sorghum plants submitted to salt stress." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17086.
Full textAbstract:
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorThe plants are frequently exposed to environmental stresses, which cause imbalances in physiological and biochemical metabolism. This work aimed to study the physiological and biochemical changes of plant forage sorghum (Sorghum bicolor) genotype CSF18, depending on the time of salt stress. The seeds were sown in vermiculite moistened with distilled water, in a greenhouse conditions, and after seven days, the seedlings were transferred to trays with Hoagland solution diluted 1:2. After seven days, treatment was established stress saline (75 mM NaCl), one group of plants kept in nutrient solution in the absence of salt (control). Samples were collected at 0, 5, 10 and 15 days after the initiation of stress. We evaluated the growth, gas exchange, contents and chlorophyll fluorescence, the concentration of organic solutes (proline, N-amino solutes, soluble carbohydrates, soluble proteins and polyamines free) and inorganic (Na+, Cl- and K+), as well as the activity of ribonuclease (RNase). We also determined the activities of catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) and guaicol peroxidase (GPX), as well as the levels of H2O2, ascorbate and glutathione in leaves and roots. Salinity reduced plant growth, being observed reductions in leaf area, and fresh and dry weights of shoots and roots. This was related to a reduction in net photosynthesis rate, even with the transpiration rate and stomatal conductance is not affected. The salinity increased contents of Na+ and Cl- in plant tissues, but the K+ decreased. The levels of organic solutes in leaves and roots increased, particularly at five and ten days of stress. The polyamines putrescine and spermidine were found at very low levels in both leaves and roots, while spermine was not detected in any analyzed portion of the plant. Although putrescine increased in salt stress, some must have contributed to the osmotic adjustment, however, their participation in oxidative protection was suggested. The salinity increased the activity of SOD, APX and GPX and the redox state of ascorbate, especially in the leaves, and this is related to the maintenance of H2O2 levels and increased protection against oxidative damage. The CAT showed the main enzyme remover H2O2 in the leaves while the roots that role was played by GPX. The RNase activity in leaves, stems and roots of sorghum increased in stress conditions, but their role in protection against the deleterious effects of salinity is not yet fully understood. In general, the data show that the antioxidative system (enzymatic and non-enzymatic) can play a key role in the acclimation of sorghum plants to salt stress, and that the reduction of plant growth was probably due to inhibition of biochemical phase of photosynthesis, caused by accumulation of toxic ions, Na+ and Cl-, reducing the relation K+/Na+ at levels harmful to the metabolism
As plantas estÃo freqÃentemente expostas a estresses ambientais, os quais causam desequilÃbrios no metabolismo fisiolÃgico e bioquÃmico. Este trabalho teve por objetivo estudar as alteraÃÃes fisiolÃgicas e bioquÃmicas de plantas de sorgo forrageiro [Sorghum bicolor (L.) Moench], genÃtipo CSF 18, em funÃÃo do tempo de exposiÃÃo ao estresse salino. As sementes foram semeadas em vermiculita umedecida com Ãgua destilada, em casa de vegetaÃÃo e, apÃs sete dias, as plÃntulas foram transferidas para bandejas com soluÃÃo nutritiva de Hoagland diluÃda 1:2. ApÃs sete dias, foi estabelecido o tratamento de estresse salino (NaCl a 75 mM), sendo um grupo de plantas mantido em soluÃÃo nutritiva na ausÃncia de sal (controle). As coletas foram realizadas aos 0, 5, 10 e 15 dias apÃs o inÃcio do estresse. Avaliou-se o crescimento, as trocas gasosas, os teores e a fluorescÃncia da clorofila, os teores de solutos orgÃnicos (prolina, N-aminossolÃveis, carboidratos solÃveis, proteÃnas solÃveis e poliaminas livres) e inorgÃnicos (Na+, Cl- e K+), bem como a atividade da ribonuclease (RNase). TambÃm foram determinadas as atividades das enzimas catalase (CAT), dismutase do superÃxido (SOD), peroxidase do ascorbato (APX) e peroxidase do guaicol (GPX), bem como os teores de H2O2, glutationa e ascorbato em folhas e raÃzes. O estresse salino reduziu o crescimento das plantas, sendo observadas reduÃÃes na Ãrea foliar, e nas matÃrias fresca e seca da parte aÃrea e das raÃzes. Isto foi relacionado com a reduÃÃo na taxa de fotossÃntese lÃquida, mesmo com a taxa de transpiraÃÃo e a condutÃncia estomÃtica nÃo sendo afetadas. A salinidade aumentou os teores de Na+ e Cl nos tecidos das plantas, porÃm, diminuiu os de K+. Os teores de solutos orgÃnicos em folhas e raÃzes aumentaram, principalmente aos cinco e dez dias de estresse. As poliaminas putrescina e espermidina foram encontradas em nÃveis muito baixos tanto em folhas como raÃzes, enquanto a espermina nÃo foi detectada em qualquer dos tecidos analisados. Embora a putrescina tenha aumentado em condiÃÃes de estresse salino, pouco deve ter contribuÃdo para o ajustamento osmÃtico, contudo, foi sugerida sua participaÃÃo na proteÃÃo oxidativa. A salinidade aumentou a atividade das enzimas SOD, APX e GPX e o estado redox do ascorbato, especialmente nas folhas, sendo isto relacionado com a manutenÃÃo dos nÃveis de H2O2 e com o aumento da proteÃÃo contra os danos oxidativos. A CAT mostrou-se a principal enzima removedora de H2O2 nas folhas, enquanto nas raÃzes esse papel foi desempenhado pela GPX. A atividade da RNase, em folhas, colmos e raÃzes de sorgo aumentou em condiÃÃes de estresse, porÃm seu papel na proteÃÃo contra os efeitos deletÃrios da salinidade ainda nÃo està totalmente esclarecido. Em geral, os dados mostram que o sistema antioxidativo (enzimÃtico e nÃo-enzimÃtico) pode desempenhar papel fundamental na aclimataÃÃo das plantas de sorgo ao estresse salino e que os efeitos deletÃrios da salinidade no crescimento das plantas, devem-se, provavelmente, à inibiÃÃo da fase bioquÃmica da fotossÃntese, causada pelo acÃmulo de Ãons tÃxicos, Na+ e Cl-, reduzindo a relaÃÃo K+/Na+ a nÃveis prejudiciais ao metabolismo.
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Ferreira, Thalita Montoril. "Respostas fisiológicas e bioquímicas de plantas de sorgo forrageiro submetidas ao estresse salino." reponame:Repositório Institucional da UFC, 2012. http://www.repositorio.ufc.br/handle/riufc/18872.
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FERREIRA, Thalita Montoril. Respostas fisiológicas e bioquímicas de plantas de sorgo forrageiro submetidas ao estresse salino. 2012. 116 f. Dissertação (Mestrado em Bioquímica)-Universidade Federal do Ceará, Fortaleza-CE, 2012.Submitted by Eric Santiago (erichhcl@gmail.com) on 2016-07-19T14:54:00Z No. of bitstreams: 1 2012_dis_tmferreira.pdf: 900415 bytes, checksum: fdb8c862f5f0003fd9c96fa54e48b94d (MD5)
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The plants are frequently exposed to environmental stresses, which cause imbalances in physiological and biochemical metabolism. This work aimed to study the physiological and biochemical changes of plant forage sorghum (Sorghum bicolor) genotype CSF18, depending on the time of salt stress. The seeds were sown in vermiculite moistened with distilled water, in a greenhouse conditions, and after seven days, the seedlings were transferred to trays with Hoagland solution diluted 1:2. After seven days, treatment was established stress saline (75 mM NaCl), one group of plants kept in nutrient solution in the absence of salt (control). Samples were collected at 0, 5, 10 and 15 days after the initiation of stress. We evaluated the growth, gas exchange, contents and chlorophyll fluorescence, the concentration of organic solutes (proline, N-amino solutes, soluble carbohydrates, soluble proteins and polyamines free) and inorganic (Na+, Cl- and K+), as well as the activity of ribonuclease (RNase). We also determined the activities of catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) and guaicol peroxidase (GPX), as well as the levels of H2O2, ascorbate and glutathione in leaves and roots. Salinity reduced plant growth, being observed reductions in leaf area, and fresh and dry weights of shoots and roots. This was related to a reduction in net photosynthesis rate, even with the transpiration rate and stomatal conductance is not affected. The salinity increased contents of Na+ and Cl- in plant tissues, but the K+ decreased. The levels of organic solutes in leaves and roots increased, particularly at five and ten days of stress. The polyamines putrescine and spermidine were found at very low levels in both leaves and roots, while spermine was not detected in any analyzed portion of the plant. Although putrescine increased in salt stress, some must have contributed to the osmotic adjustment, however, their participation in oxidative protection was suggested. The salinity increased the activity of SOD, APX and GPX and the redox state of ascorbate, especially in the leaves, and this is related to the maintenance of H2O2 levels and increased protection against oxidative damage. The CAT showed the main enzyme remover H2O2 in the leaves while the roots that role was played by GPX. The RNase activity in leaves, stems and roots of sorghum increased in stress conditions, but their role in protection against the deleterious effects of salinity is not yet fully understood. In general, the data show that the antioxidative system (enzymatic and non-enzymatic) can play a key role in the acclimation of sorghum plants to salt stress, and that the reduction of plant growth was probably due to inhibition of biochemical phase of photosynthesis, caused by accumulation of toxic ions, Na+ and Cl-, reducing the relation K+/Na+ at levels harmful to the metabolism
As plantas estão freqüentemente expostas a estresses ambientais, os quais causam desequilíbrios no metabolismo fisiológico e bioquímico. Este trabalho teve por objetivo estudar as alterações fisiológicas e bioquímicas de plantas de sorgo forrageiro [Sorghum bicolor (L.) Moench], genótipo CSF 18, em função do tempo de exposição ao estresse salino. As sementes foram semeadas em vermiculita umedecida com água destilada, em casa de vegetação e, após sete dias, as plântulas foram transferidas para bandejas com solução nutritiva de Hoagland diluída 1:2. Após sete dias, foi estabelecido o tratamento de estresse salino (NaCl a 75 mM), sendo um grupo de plantas mantido em solução nutritiva na ausência de sal (controle). As coletas foram realizadas aos 0, 5, 10 e 15 dias após o início do estresse. Avaliou-se o crescimento, as trocas gasosas, os teores e a fluorescência da clorofila, os teores de solutos orgânicos (prolina, N-aminossolúveis, carboidratos solúveis, proteínas solúveis e poliaminas livres) e inorgânicos (Na+, Cl- e K+), bem como a atividade da ribonuclease (RNase). Também foram determinadas as atividades das enzimas catalase (CAT), dismutase do superóxido (SOD), peroxidase do ascorbato (APX) e peroxidase do guaicol (GPX), bem como os teores de H2O2, glutationa e ascorbato em folhas e raízes. O estresse salino reduziu o crescimento das plantas, sendo observadas reduções na área foliar, e nas matérias fresca e seca da parte aérea e das raízes. Isto foi relacionado com a redução na taxa de fotossíntese líquida, mesmo com a taxa de transpiração e a condutância estomática não sendo afetadas. A salinidade aumentou os teores de Na+ e Cl nos tecidos das plantas, porém, diminuiu os de K+. Os teores de solutos orgânicos em folhas e raízes aumentaram, principalmente aos cinco e dez dias de estresse. As poliaminas putrescina e espermidina foram encontradas em níveis muito baixos tanto em folhas como raízes, enquanto a espermina não foi detectada em qualquer dos tecidos analisados. Embora a putrescina tenha aumentado em condições de estresse salino, pouco deve ter contribuído para o ajustamento osmótico, contudo, foi sugerida sua participação na proteção oxidativa. A salinidade aumentou a atividade das enzimas SOD, APX e GPX e o estado redox do ascorbato, especialmente nas folhas, sendo isto relacionado com a manutenção dos níveis de H2O2 e com o aumento da proteção contra os danos oxidativos. A CAT mostrou-se a principal enzima removedora de H2O2 nas folhas, enquanto nas raízes esse papel foi desempenhado pela GPX. A atividade da RNase, em folhas, colmos e raízes de sorgo aumentou em condições de estresse, porém seu papel na proteção contra os efeitos deletérios da salinidade ainda não está totalmente esclarecido. Em geral, os dados mostram que o sistema antioxidativo (enzimático e não-enzimático) pode desempenhar papel fundamental na aclimatação das plantas de sorgo ao estresse salino e que os efeitos deletérios da salinidade no crescimento das plantas, devem-se, provavelmente, à inibição da fase bioquímica da fotossíntese, causada pelo acúmulo de íons tóxicos, Na+ e Cl-, reduzindo a relação K+/Na+ a níveis prejudiciais ao metabolismo.
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Alonis, Melenie Lee. "Selenotrisulfide Derivative of Alpha-Lipoic acid: Evaluation in a Cell Culture Model for Potential Use as a Topical Antioxidant." Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3451.
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Selenium is a required micronutrient in mammalian cells. It is incorporated in the form of selenocysteine into selenoenzymes such as glutathione peroxidase and thioredoxin reductase, and is absolutely required for activity. Thioredoxin reductase is necessary for reduction of oxidized thioredoxin and therefore plays a major role in maintaining the redox status of the cell. Glutathione peroxidase is responsible for reducing peroxides into their corresponding alcohols and water. Together, these selenoenzymes constitute a significant part of the cell's arsenal to defend itself against oxidative stress. Exogenous sources of oxidative stress, such as UV radiation, are capable of generating reactive oxygen species (ROS). Elevated levels of ROS can lead to covalent modifications of lipids, nucleic acids, and proteins within a cell. This damage has been implicated in the development of cancer and degenerative diseases. As the skin is the first level of defense for UV radiation, skin cancer is an obvious concern. Previous studies have demonstrated a protective effect against UV-induced cytotoxicity when selenium compounds were administered to skin cells in cell culture models. Topical selenium application to mice has also been shown to reduce UV damage to skin. Although a variety of chemical forms of selenium are available in nutritional supplements, the efficiency by which they are used for selenoprotein synthesis varies greatly. It is debated within the selenium research community which form is best for use as a supplement. In this study, we have focused on a selenotrisulfide derivative of alpha-lipoic acid (LASe). We have examined its utilization for selenoprotein synthesis through radiolabeling studies (75Se) in a human keratinocyte cell line (HaCaT). We have determined that is incorporated into selenoproteins with nearly the same efficiency as selenite and L-selenocysteine. We have also determined that LASe is far more efficient as a supplement in cell culture than selenate or L-selenomethionine, two forms of selenium commonly used as supplements. LASe was also found to protect HaCaT keratinocytes from UV- induced cytotoxicity. Cells pretreated with LASe and exposed to 500J/m2 and 750J/m2 of broadband (UVA/UVB) UV radiation showed greater survival than untreated controls in a dose –dependent manner. Cells pre-treated either with lipoic acid or selenium in the form of selenite alone also observed protection. Nonetheless, these finding are significant given that LASe was previously shown to penetrate the skin better than other forms of selenium. These results indicate that LASe has the potential for use as a topical antioxidant upon further testing in animal studies.M.S.
Department of Molecular Biology and Microbiology
Burnett College of Biomedical Sciences
Molecular Biology and Microbiology
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Matsumoto, Ruth Lobato Teixeira. "Atividade antioxidante do chá mate (Ilex paraguariensis)." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/6/6133/tde-21072008-150005/.
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INTRODUÇÃO: A erva-mate (Ilex paraguarienis), uma planta nativa e consumida em grande parte da América do Sul, apresenta diversos compostos bioativos que já demonstraram importante atividade antioxidante in vitro e in vivo. O chá mate é um produto desta planta cujas propriedades antioxidantes ainda não foram avaliadas em ensaios com humanos. OBJETIVO: Este projeto visa avaliar o potencial antioxidante do chá mate in vivo e ex vivo sobre o plasma e LDL de humanos após a ingestão de chá-mate. MÉTODOS: Indivíduos em jejum (n=20) tiveram seu sangue coletado em três momentos: antes, após uma hora e depois de 1 semana (7 dias) da ingestão diária de chá-mate. O plasma e a LDL obtidos nos três momentos foram submetidos à oxidação por três mecanismos diferentes [Cobre (Cu+2), lipoxigenase e peroxinitrito (SIN-1)] e em seguida foram medidos os produtos de peroxidação lipídica formados: a concentração de TBARs (substâncias reativas ao ácido tiobarbitúrico) e a formação de dienos conjugados empregando-se métodos espectrofotométricos. Também foram determinados o perfil antioxidante total do plasma (TAS), avaliação da lipoperoxidação plasmática basal (TBARs), avaliação da fragmentação da Apolipoproteína B após oxidação da LDL, por eletroforese em gel com SDS-PAGE e os níveis de expressão, por meio de análise de PCR real time, de alguns genes relacionados à produção de enzimas antioxidantes. Teste t de Student pareado foi utilizado para verificar se houve diferença estatisticamente significante entre os resultados das diversas análises antes e após o consumo do chá. RESULTADOS: Os resultados obtidos pela maioria dos ensaios realizados demonstraram que o consumo de chá mate aumentou a resistência à oxidação, a capacidade antioxidante plasmática e a expressão de genes relacionados à produção de enzimas antioxidantes. CONCLUSÃO: Esses resultados sugerem que o consumo de chá mate por período curto pode atuar como antioxidante por múltiplos mecanismos e portanto pode contribuir para diminuição do risco de desenvolvimento de doenças crônicas relacionadas a processos oxidativo.Yerba Mate (Ilex paraguariensis) is a native and widely consumed South American plant. It contains high concentrations of bioactive compounds that respond for its high antioxidant activity in vitro and in vivo. This activity has not been demonstrated yet in humans for the mate tea, a product derived from Yerba Mate. OBJECTIVE: The aim of this study was to evaluate the antioxidant activity of maté tea in vivo and ex vivo on plasma and LDL human after ingestion of mate tea infusion. METHODS: Fasting peripheral venous blood samples of twenty healthy women (n=20) were taken in three different times: before drinking the tea, one hour later and after one week of daily consumption (7 days) of mate tea. The plasma and isolated LDL were oxidated with 3 different systems [copper (CuSO4), lipoxygenase and peroxynitrite (SIN-1)]. Next, the peroxidation products evaluated were: concentration of malonaldeyde (TBA) and conjugated dienes (lag time), using spectrophotometric methods. We also measured the plasma total antioxidant status (TAS), serum levels of malondialdehyde (MDA) as thiobarbituric substances (TBARS), fragmentation of apo B using SDS-PAGE and the level of antioxidant enzyme gene expression by PCR real time. Paired t student test was used to analyze the results before and after ingestion of mate tea. RESULTS: The results obtained by most of the tests showed that mate tea ingestion increased the plasma and LDL resistance by ex vivo oxidation, the plasma antioxidant capacity and the level of antioxidant enzyme gene expression. CONCLUSION: This study suggests that regular consumption of mate tea can act as an antioxidant by multiple mechanisms and thus may contribute decrease the risk of developing chronic diseases related to oxidative processes.
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Basson, Gerhard Leroy. "3,3'-diindolylmethane improves drought tolerance of Zea mays through enhancing antioxidant activity." University of the Western Cape, 2018. http://hdl.handle.net/11394/6750.
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>Magister Scientiae - MScMaize is one of the most abundantly produced cereals and contributes to about 40% of the global cereal production. This figure will have to increase in order to feed the ever-growing human population. One of the major environmental constraints that impact maize production is drought. Plants use antioxidant defences to cope with drought stress. Understanding and improving these defence mechanisms will be important to improve overall drought tolerance. A previous study done by Gokul and authors in 2016 showed that 3,3’-diindolylmethane (DIM) improves both seed germination and seedling shoot growth in Brassica napus. Plants belonging to the Brassicaceae family have the metabolic machinery to synthesize glucosinolates such as DIM, which play vital roles in physiological and stress responses. These responses have not been investigated in plants such as maize, which lack the machinery to produce DIM. Therefore, this study investigated the effects of exogenously applied DIM on the physiological and biochemical responses of maize under drought stress. Physiological parameters such as relative water content, chlorophyll content and lipid peroxidation, were determined in order to understand how drought and DIM , as separate or combined treatments, affected the plants. Additionally, proline accumulation was also assessed because free proline plays a role as an osmoprotectant during stress. The accumulation of ROS, namely hydrogen peroxide, was measured using spectrophotometric assays to determine how the above treatments affect ROS accumulation in maize. As a result of changes in the ROS content in due to the treatments, it would only be natural to investigate the changes in antioxidants as well. Given that hydrogen peroxide was the ROS to be measured, we therefore investigated the antioxidant enzymatic activities responsible for hydrogen peroxide scavenging. Therefore, changes in Ascorbate peroxidase (APX) and catalase (CAT) were assessed. An improved drought response was observed in maize plants treated with DIM as these plants had better ability to maintain their water status than when no DIM was applied. This is indicated by water-deprived plants treated with DIM having a higher RWC than water-deprived plant without DIM.
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Ferreira, Leonardo Cesar [UNESP]. "Ação protetora do óxido nítrico em plantas de soja (Glycine max L. Merril) submetidas ao lactofen." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/100775.
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O lactofen é um herbicida do grupo dos difenil-éteres utilizado na cultura da soja para o controle de plantas daninhas de folhas largas e possui como mecanismo de ação a inibição da enzima protoporfirinogênio oxidase (Protox), que catalisa a etapa de oxidação do protoporfirinogênio-IX a protoporfirina-IX (proto-IX) na via de biossíntese das clorofilas e citocromos. A inibição é seguida de um acúmulo de proto- IX, que leva à formação de espécies reativas do metabolismo do oxigênio (ERMO), peroxidação de lipídios das membranas e diminuição dos teores de pigmentos fotossintéticos, caracterizando-se assim o estresse oxidativo. Como conseqüência, podem ocorrer manchas, enrugamento e queima das folhas, levando à paralisação temporária do crescimento da cultura. Em contrapartida, o óxido nítrico (NO) é uma molécula capaz de eliminar diretamente as ERMO e assim finalizar reações propagadas em cadeia, podendo atuar como um antioxidante. Desta forma, o presente estudo teve como objetivo avaliar se o pré-tratamento de plantas de soja com solução de nitroprussiato de sódio (SNP), substância doadora de NO, promove proteção contra o estresse oxidativo gerado pelo lactofen. Assim, plantas de soja no estádio fenológico V3, após pré-tratamento com as diferentes doses de SNP (0, 50, 100 e 200 μmol.L-1) por dois dias consecutivos, foram pulverizadas com lactofen na dose recomendada para esta cultura, equivalente a 0,7 L.ha-1. Às 24, 48, 72, 96 e 120 h após a aplicação de lactofen (HAAL), folíolos foram coletados para a quantificação dos teores de lipoperóxidos, clorofilas totais e suas frações a e b e carotenóides totais, bem como para a determinação da atividade das enzimas antioxidantes glutationa S-transferase (GST), superóxido dismutase (SOD), catalase (CAT) e peroxidase (POD). Além disso,...
Lactofen is a diphenylether herbicide applied in soybean fields to control broadleaf weeds whose mechanism of action is the inhibition of protoporphyrinogen oxidase (Protox) enzyme, which catalyses oxidation of protoporphyrinogen-IX to protoporphyrin-IX (proto-IX) in the chlorophyll and cytochrome biosynthesis pathway. This inhibition is followed by accumulation of proto- IX, which leads to generation of reactive oxygen species (ROS), lipid peroxidation of membranes and decrease of photosynthetic pigment levels, which characterizes oxidative stress. Consequently, spots, wrinkles and leaf burn can occur, which results in transitory cessation of crop growth. However, nitric oxide (NO) is a molecule able to scavenge ROS directly and to end chain reactions, acting as an antioxidant. Thus, the present research aimed to evaluate if the pre-treatment of soybean plants with sodium nitroprusside (SNP) solution, a NO donor substance, promotes protection against oxidative stress generated by lactofen. Thus, soybean plants at V3 phenologic stage were pre-treated with different SNP levels (0, 50, 100 and 200 μmol.L-1) for two consecutive days and on the third day were sprayed with lactofen at recommended rate for this crop, equivalent to 0.7 L.ha-1. At 24, 48, 72, 96 and 120 h after application of lactofen (HAAL), leaflets were collected in order to quantify the levels of lipoperoxides, total chlorophylls and their a and b fractions, total carotenoids, as well as the activity assay of glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) antioxidant enzymes. In addition, at two, four and seven days after application of lactofen (DAAL), visual injury evaluations were performed, and at 7 and 14 DAAL, the plants were evaluated for height, root length and leaflets number count. Afterwards, the plants were separated into leaf blades,...(Complete abstract click electronic access below)
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Rodrigues, Viviane Drumond 1983. "Analise de proteinas e genes envolvidos no metabolismo energetico e sistema antioxidante em Acidithiobacillus ferrooxidans LR." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316921.
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Orientador: Laura Maria Mariscal OttoboniDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Acidithiobacillus ferrooxidans é uma bactéria Gram negativa, anaeróbica facultativa, acidofílica, quimiolitotrófica e mesofílica. A. ferrooxidans é capaz de utilizar ferro e enxofre como fonte de energia e é um dos microrganismos mais utilizados no processo de biolixiviação. Durante este processo a bactéria pode estar sujeita a diversos tipos de estresse, entre eles, o estresse oxidativo. Entre os principais sensores relacionados à resposta antioxidante estão: a enzima SOD e as proteínas dos sistemas tiorredoxina e glutarredoxina. A SOD atua como defesa primária na remoção de espécies reativas do oxigênio. O sistema tiorredoxina é composto por NADPH, TrxR e Trx. O sistema glutarredoxina é formado por NADPH, GR, GSH e Grx. Os sistemas tiorredoxina e glutarredoxina desempenham um papel fundamental contra espécies reativas do oxigênio e na manutenção do ambiente redutor da célula. No primeiro capítulo, a linhagem brasileiraA. ferrooxidans LR foi utilizada para o estudo da expressão de genes dos sistemas tiorredoxina e glutarredoxina, por PCR em tempo real, em diferentes condições: (a) nas taxas de 50, 75 e 100% de oxidação de Fe2+, (b) em um e dois dias após a taxa de 100% de oxidação de Fe2+, (c) na presença de calcopirita e (d) após diferentes tempos de heat shock. Em geral, nas diferentes taxas de oxidação de Fe2+, os genes do sistema tiorredoxina foram mais expressos que os do sistema glutarredoxina. Em um dia após 100% de oxidação de Fe2+, a maioria dos genes teve expressão induzida. Em dois dias a partir desta taxa de oxidação de Fe2+, apenas os genes trxB e gor foram induzidos em relação ao controle, sugerindo que os produtos desses genes podem exercer a função de chaperona durante o estresse oxidativo. Na presença de calcopirita, apenas o gene gor foi induzido, indicando que GR pode estar envolvida no controle da homeostase celular. Esta enzima também pode ser necessária para a atividade de GSH, proteína envolvida no metabolismo de enxofre. Após o heat shock, os níveis de expressão do gene que codifica a proteína Grx3 aumentaram significativamente, possivelmente devido à propriedade de co-chaperona da proteína. No segundo capítulo foram feitas análises in silico das sequências de aminoácidos das proteínas GR, TrxR e SOD de A. ferrooxidans. A análise de in silico mostrou que existem muitas semelhanças entre as proteínas TrxR e GR, como por exemplo, estrutura secundária, peso molecular, sítio ativo, motivos funcionais e domínios. Foi realizada a quantificação de proteínas totais, a determinação da atividade em espectrofotômetro das enzimas GR e TrxR, a atividade em PAGE não desnaturante das proteínas GR e SOD e a caracterização de SOD durante o crescimento de A. ferrooxidans LR em ferro e em células mantidas em contato com a calcopirita por 1 e 10 dias. A concentração de proteínas totais foi menor em células mantidas por 10 dias em contato com a calcopirita, e uma das razões pode ser o maior estresse oxidativo. A atividade das enzimas GR, TrxR e SOD aumentou neste mesmo período de tempo, sugerindo a presença de estresse. A caracterização com KCN e H2O2 mostrou que a enzima SOD de A. ferrooxidans era do tipo FeSOD.
Abstract: Acidithiobacillus ferrooxidans is a Gram-negative, anaerobic facultative, acidophilic, chemolithoautotrophic and mesophilic bacterium. A. ferrooxidans is able to use iron and sulfur as energy source and is one of the microorganisms used in the bioleaching process. During this process, the bacterium may be subjected to several stressful situations including the oxidative stress. Among the proteins involved in the antioxidant response are the enzyme SOD and the proteins from the thioredoxin and the glutaredoxin systems. SOD removes the reactive oxygen species. The thioredoxin system is composed by NADPH, TrxR and Trx. The glutaredoxin system consists of NADPH, GR, GSH and Grx. The thioredoxin and the glutaredoxin systems play a key role against the reactive oxygen species and maintain the reducing environment of the cell. In the first chapter, the Brazilian strain A. ferrooxidans LR was used to study the expression of genes from the thioredoxin and the glutaredoxin systems, by real-time PCR, in different conditions: (a) at 50, 75 and 100% of Fe2+ oxidation, (b) in one a and in two days after 100% of Fe2+ oxidation, (c) in the presence of chalcopyrite and (d) after different periods of time of heat shock. In general, on the different rates of Fe2+ oxidation, the genes of the thioredoxin system showed a higher expression than the genes from the glutaredoxin system. In one day after 100% of oxidation of Fe2+, the majority of the genes had their expression induced. In two days after 100% of oxidation of Fe2+, only the genes trxB and gor were induced suggesting that the product of these genes may act as chaperones during the oxidative stress. In the presence of chalcopyrite, only the gene gor was induced, indicating that GR may be involved in the control of the cell homeostasis since it is necessary for GSH activity, a protein that participates in sulfur metabolism. After the heat shock, the expression of the gene that encodes the protein Grx3 increased, probably because this protein can act as a cochaperone. In the second chapter, an in silico analysis of the proteins GR, TrxR and SOD amino acids sequences from A. ferrooxidans was performed. This analysis showed that there are several similarities between TrxR and GR including, secondary structure, molecular weight, active site, functional motives and domains. Total protein content in cells grown until 80% of oxidation of Fe2+ and in cells kept for 1 and 10 days in the presence of chalcopyrite was determined. Also, in these conditions, the activities of GR and TrxR were determined in a spectrophotometer and the activities of GR and SOD were determined in gel. The total protein content was higher in control cells and in the contrary, enzyme activities were higher at 10 days of bacteria contact with chalcopyrite indicating the presence of oxidative stress. Assays with KCN and H2O2 showed that the A. ferrooxidans LR SOD was in fact a FeSOD.
Mestrado
Genetica de Microorganismos
Mestre em Genética e Biologia Molecular
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Ferrari, Rosana. "Efeitos da administração de ácido indol-3-acético (AIA) sobre parâmetros metabólicos e eletroencefálicos de ratos." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/74/74131/tde-24102008-095444/.
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O ácido indol-3-acético (AIA) é um produto do metabolismo do triptofano encontrado nos organismos animais, vegetais e em microrganismos. Destacam-se os trabalhos que atribuíram ao AIA efeitos tanto antioxidantes quanto proxidantes em diferentes sistemas biológicos. O objetivo do presente estudo foi o de avaliar os efeitos da administração do AIA no metabolismo muscular e cerebral e na atividade elétrica cerebral de ratos. Foram realizados dois grupos de experimentos. No primeiro grupo foram avaliados os seguintes parâmetros: taxa glicêmica e o ganho de peso corporal de animais tratados por 14 dias com AIA (40 mg/Kg de peso vivo, via intragástrica); atividade das enzimas antioxidantes glutationa redutase (GR), catalase (CAT) e superóxido dismutase (SOD) e das enzimas do metabolismo da glicose hexoquinase (HQ), lactato desidrogenase (LDH) e glicose-6-fosfato desidrogenase (G6PDH) nos músculos sóleo e gastrocnêmio e a atividade da enzimas antioxidantes GR, CAT e SOD e a quantificação dos produtos resultantes da peroxidação lipídica (TBARs) no cérebro de ratos tratados por 14 dias com diferentes doses de AIA (1, 18 e 40 mg/Kg de peso animal, via intragástrica). Os respectivos controles de todas essas análises foram obtidos de ratos que receberam 1 mL de tampão fosfato pH 7,4 via intragástrica sob as mesmas condições experimentais. No segundo grupo de experimentos foi obtido o eletroencefalograma (EEG) dos animais. O EEG obtido foi filtrado nas bandas de freqüências delta (0,3-4 Hz), teta (4-8 Hz), alfa (8-12 Hz) e beta (12-30 Hz) e em cada banda calculou-se a energia do sinal. Foram avaliados o EEG de animais tratados com AIA (40 mg/Kg de peso vivo) e tratados com triptofano (40 mg/Kg de peso animal), ambos por via intragástrica. Os controles para esses tratamentos foram o EEG coletado 1 hora antes e 1 hora depois da administração de 1mL de tampão fosfato por via intragástrica no mesmo animal que recebeu o tratamento. Os resultados foram analisados por ANOVA com significância de 0,05 usando o teste de Tuckey e os estimadores foram validados usando-se bootstrap. A adminitração de AIA (40mg/Kg de peso vivo) não alterou a taxa glicêmica e evolução de peso corporal dos animais, em relação ao controle. Não foram observadas diferenças significativas entre os resultados obtidos de amostras de animais tratados com AIA (todas as doses) em relação aos respectivos controles para: atividade das enzimas antioxidantes muscular e cerebral; enzimas envolvidas com o metabolismo da glicose muscular; conteúdo de peroxidação lipídica (TBARs) cerebral. O método não invasivo de aquisição de EEG desenvolvido para ratos permitiu adquirir e analisar o sinal elétrico cerebral. Não foram observadas alterações no padrão do EEG após a administração de tampão fosfato. No entanto, o AIA na dose de 40 mg/Kg de peso vivo alterou o padrão do EEG do animal, pois, a energia das freqüências de ondas alfa (8-12 Hz) e beta (12-30 Hz) foi maior em relação ao estado normal e após administração de tampão fosfato. Já o triptofano na dose de 40 mg/Kg de peso vivo aumentou a energia da onda delta (0,3-4 Hz) e diminuiu na energia da onda beta (12-30 Hz) em relação ao estado normal. O método não invasivo de EEG para rato desenvolvido neste trabalho foi sensível para detectar a atividade elétrica encefálica dos animais e o triptofano serviu como parâmetro de referência, pois promoveu diferentes alterações no padrão do EEG daquelas observadas nos animais tratados com AIA. Conclui-se que o AIA não interferiu nos parâmetros metabólicos oxidativos e energéticos dos músculos e do cérebro dos animais estudados, mas promoveu alterações fisiológicas que desencadearam as mudanças observadas na energia do sinal de EEG dos animais.Indole-3-acetic acid (IAA) is a tryptophan metabolic found in animals organisms, microorganisms and vegetables. It is remarkable the work done to IAA antioxidants and proxidants effects in several biological systems. The main purpose of these studies was to evaluate the effects of intragastric IAA administration in brain and in muscle metabolism and electrical brain activities in rat. The experiments were done in two groups. The first one, were evaluated the following parameters: glycemic rate and corporal gain weight to those animals treated14 days with IAA (40 mg/Kg of body weight); activity of antioxidants enzymes as glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD); activities of hexokinase (HQ), lactate dehidrogenase (LDH) and glucose-6-phosphate dehidrogenase (G6PDH) on soleus and gastrocnemic muscle; antioxidants enzymes activities and level of tiobarbituric reactives subtances (TBARs) in brain from rats treated during 14 days with doses of IAA (1,18 and 40 Kg/kg body of weight). All those analyses controls were obtained from rat that was given 1 mL of phosphate buffered saline, pH 7 (PBS), under the same experiments conditions as the group treated with IAA. On the second group of experiments was evaluated EEG pattern obtained from fixed electrodes on the animal skin surface were not sedated, and shown at delta frequency (0.3-4 Hz), theta (4-8 Hz), alpha (8-12 Hz) and beta (12-30 Hz) and the energy of those band frequency was calculated using a developed algorithm software MATLAB®. EEG was evaluated from animals treated with IAA (40 mg/Kg body weight) and treated with tryptophan (40 mg/Kg body weight), both intragastric. The management control for those treatments were EEG collected 1 hour before and 1 hour after the intragstric administration of 1mL PBS at the same animal that received the treatment. The results were analysed by ANOVA with great significance of 0.05 using the Tukey test and were evaluated by bootstrap. The IAA administration (40 mg/Kg body weight) did not change the glycaemia rate and the animal weight evolution, to compare with the control. Were not observed any significant differences among results from animals treated with IAA (all doses) relating to respective controls to: a) brain and muscles antioxidants enzymes activity; b) activities of enzymes with muscular glucose metabolism; c) brain lipid peroxidation contents by TBARs level. No invasive EEG colleting methods developed for rat allowed to collect and analyse electric brain signal. After an administration of PBS, were not observed any changes at EEG pattern. IAA dose of 40 mg/Kg body weight did change the animal EEG standard, the frequency energy of alpha wave to (8-12 Hz) and beta (12-30 Hz) was higher then normal after administration of PBS. On the other side, tryptophan dose of 40 mg/Kg body weight increased the delta wave energy to (0,3-4 Hz) and decreased the beta wave energy to (12-30 Hz), to compare withfthe normal standard. Non invasion EEG colleting methods for rat developed in this studies was sensible in order to detect an animals electric encephalic activity and the tryptophan became as reference parameter, due to several changes on pattern EEG to those animals treated with IAA. Concluding that, IAA did not interfere on oxidative metabolic parameters, neither to the brain and muscles of the studied animals, but promoted physiological changes that was possible to observe on animals electroencephalogram.
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Porto, Erly Carlos. "Estresse oxidativo mediado por extrato aquoso de Bauhinia forficata L. durante a fase de germinação e desenvolvimento de Phaseolus vulgaris L." Universidade Estadual do Oeste do Paraná, 2018. http://tede.unioeste.br/handle/tede/3807.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Plant species can interact with each other through the production and release of chemical compounds released into the environment, such an event is known as allelopathy. The objective of the present study was to investigate the allelopathic action and oxidative stress of the aqueous extract of Bauhinia forficata L. on seeds during the germination process and seedlings during the Phaseolus vulgaris development phase. The germination behavior, allelopathic activity index, initial growth and activity of antioxidant enzymes were studied at different times of seed imbibition, in the cotyledon (reserve tissue) and in the embryonic axis and seedlings, for aerial part and root target species. The results indicated that during the germination phase there was negative interference of B. forficata extracts on the seeds for germination, speed index and mean germination time, as well as the allelopathic activity index. In relation to the enzymatic activity, a high enzyme activity was observed at the beginning of seed imbibition, between 3 and 6 hours for the cotyledon and high activity in the embryonic axis at the end of the germination process, between 12 and 24 hours of imbibition. The increase of the extract proportions of the leaves of B. forficata affected the enzymatic activities in the germination process of the bean seeds, resulting in a delay of the germination. As for the development phase, there was reduction of the average length and dry mass of the root as the proportion of extract used increased. the levels of lipid peroxidation for both shoot and root were high, as well as the activity of the catalase enzyme for the roots was also elevated when submitted to the treatments with the presence of the extract. Thus, the increase in the proportion of B. forficata extract negatively affected the initial development, being the primary root elongation more sensitive, causing severe damage to the membranes of the bean seedlings roots.
As espécies vegetais podem interagir entre si por meio da produção e liberação de compostos químicos liberados no ambiente, tal evento é conhecido como alelopatia. Desta forma, o objetivo do presente estudo foi investigar a ação alelopática e o estresse oxidativo do extrato aquoso de Bauhinia forficata L. sobre sementes de Phaseolus vulgaris, durante o processo de germinação e desenvolvimento das plântulas. Para isso, foram avaliados o comportamento germinativo, o índice de atividade alelopática, o crescimento inicial e a atividade de enzimas antioxidantes em diferentes tempos de embebição das sementes, no cotilédone (tecido de reserva) e no eixo embrionário e plântulas, para a parte aérea e raiz da espécie alvo. Os resultados indicaram que durante a fase de germinação houve interferência negativa dos extratos de B. forficata sobre as sementes para as variáveis: germinação, índice de velocidade e tempo médio de germinação, como também para o índice de atividade alelopática. Em relação a atividade enzimática, foi verificado uma alta atividade das enzimas no início da embebição das sementes, entre 3 e 6 horas para o cotilédone e elevada atividade no eixo embrionário ao final do processo germinativo, entre 12 e 24 horas de embebição. O aumento das proporções de extrato das folhas de B. forficata afetaram as atividades enzimáticas no processo germinativo das sementes de feijão resultando um atraso da germinação. Já para a fase de desenvolvimento, houve redução do comprimento médio e massa seca da raiz conforme o aumento das proporções de extrato utilizados. Os níveis de peroxidação lipídica tanto para parte aérea e raiz foram elevados, assim como a atividade da enzima catalase para as raízes também foi elevado quando submetidos aos tratamentos com a presença do extrato. Desta forma, o aumento das proporções de extrato de B. forficata L. afetou negativamente o desenvolvimento inicial, sendo o alongamento da raiz primaria mais sensível, provocando danos acentuados as membranas das raízes de plântulas de feijão.
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Silva, Magnun Antonio Penariol da [UNESP]. "Secagem e armazenamento de grãos de crambe [Crambe hyspanica subesp. abyssinica (Hochst ex R.E.Fr) PRINA] para uso na produção de biodiesel." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/149850.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
A cultura do crambe começou a ser estudada no Brasil por apresentar elevado teor de óleo nos grãos. A produção é totalmente mecanizada e de baixo custo por utilizar as ferramentas disponíveis para outras espécies. O crambe é uma cultura de inverno, então se torna também uma excelente opção para o cultivo em safrinha. No entanto a cultivar desenvolvida para a comercialização no país apresenta maturação irregular dos grãos, o que se torna um problema tanto para a colheita quanto para os processos pós-colheita, por não se haver uma época ideal para colheita mecanizada sem que ocorram perdas durante esta etapa, ou ainda durante a secagem e armazenamento. Diante do exposto, o objetivo do presente trabalho foi acompanhar o processo de secagem dos grãos de crambe, e ainda o período de 12 meses de armazenamento, relacionando esses processos com a dinâmica de formação de lipídeos dos grãos, os sistemas antioxidantes, o acúmulo de açúcares, lipídeos e proteínas ao longo do desenvolvimento, os estresses ocasionados pela secagem e a pigmentação durante o armazenamento. Para isso, um experimento foi instalado na área de produção da Fazenda Experimental Lageado, onde utilizou-se para semeadura sementes de crambe da cultivar FMS Brilhante (Fundação Mato Grosso do Sul), na qual o processo foi acompanhado semanalmente verificando os teores de água dos grãos (82, 74, 60, 40, 30, 20 e 10%) que foram submetidos à diferentes métodos de secagem (testemunha, natural, secagem em estufa à 30ºC e secagem em estufa à 40ºC). Para melhor entendimento dos dados obtidos este trabalho foi dividido em quatro capítulos. O primeiro capítulo trata-se de uma revisão de literatura a respeito dos processos de desenvolvimento, secagem e armazenamento de grãos de crambe. O segundo capítulo estudou a dinâmica de formação de lipídeos nestes grãos. No terceiro capítulo avaliou-se o acúmulo das principais reservas (proteínas, açúcares e lipídeos) e os danos oxidativos ocasionados pela secagem dos grãos. E no quarto o foco foi verificar se o tempo de armazenamento afeta as reservas, pigmentação e a atividade enzimática dos grãos. Conclui-se que a maior reserva encontrada em grãos de crambe são os lipídeos, seguido por açúcares e proteínas, os grãos de crambe apresentam maior acúmulo de lipídeos aos 49 dias após a floração, a secagem à 80 ºC provoca danos aos grãos e que os grãos de crambe começam aumentar o conteúdo de pigmentos à partir dos 6 meses de armazenamento.
The culture of crambe began to be studied in Brazil by a high oil content in grain. The production is fully mechanized and low cost to use the tools available for other species. It is a winter crop, then it also makes an excellent choice for growing in off-season. However cultivating developed for sale in the country is irregular grain maturity, which becomes a problem for both the harvest time to post-harvest processes, not be an ideal time for mechanized harvesting without incurring losses during this step or during drying and storage. Given the above, the objective of this study was to follow up the development process of crambe grain, and also the steps of drying and storage, linking these processes with the dynamics of grain lipid formation, antioxidant systems, the accumulation of sugars , lipids and proteins throughout the development of the stresses caused by drying and pigmentation during storage. For this, an experiment was conducted in the area of Fazenda Experimental Lageado. We used to cultivate the crambe sowing seeds FMS Brilhante (Fundação Mato Grosso do Sul), in which the process was monitored weekly by checking the water content of grains (82, 74, 60, 40, 30, 20 and 10%) which were subjected to different drying methods (control, natural drying oven at 30 ° C and dried at 40 ° C). For better understanding of the data from this study was divided into four chapters. The first chapter it is a literature review about the development processes, drying and crambe grain storage. The second chapter studied the dynamics of the formation of lipids in these grains. In the third chapter, we evaluated the accumulation of the main reserves (proteins, sugars and lipids) and the oxidative damage caused by the drying of the beans. And in the room the focus was to determine whether the storage time affects the reserves, pigmentation and the enzymatic activity of the grains. It follows that the largest reserve found in crambe grains are lipids, followed by sugars and proteins, crambe grains have higher accumulation of lipids at 49 days after flowering, drying at 80 ° C causes damage to the beans and that crambe grains begin to increase the content of pigments from 6 months of storage.
CNPq: 140263/2013-6
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Wiegand, Heike. "Effects of dietary flavonoids on vitamin E status and hepatic phase II and antioxidant enzymes." Tönning Lübeck Marburg Der Andere Verl, 2008. http://d-nb.info/991846540/04.
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Braaf, Ryan. "Zirconium-induced physiological and biochemical responses in two genotypes of Brassica napus L." University of the Western Cape, 2015. http://hdl.handle.net/11394/4874.
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>Magister Scientiae - MScSouth Africa is one of two countries responsible for the production of approximately 80% of the world’s Zr. The increase in mining activity has detrimental effects on the environment, especially crop plants, as more pollutants are leached into the soil. Consequently, it is necessary to understand how plants respond to this form of abiotic stress. Therefore, this study focused on determining the physiological and biochemical responses of two genotypes of Brassica napus L (Agamax and Garnet) in response to Zr stress. The levels of cell death, lipid peroxidation and ROS were higher in Garnet, whereas the chlorophyll content was higher in Agamax. Furthermore, native PAGE analysis detected seven SOD isoforms and seven APX isoforms in Agamax, compared to 6 SOD isoforms and 7 APX isoforms in Garnet. The results thus indicate that Agamax is tolerant to Zr-induced stress, whereas Garnet is sensitive. An assay for the rapid quantification of Zr within plant samples was subsequently developed, which revealed that Agamax retained the bulk of the Zr within its roots, whereas Garnet translocated most of the Zr to its leaves. The ability of Agamax to sequester Zr in its roots comes forth as one of the mechanisms which confers greater tolerance to Zr-induced stress. As a consequence, our study sought to use the optical, physical and chemical properties of quantum dots to image the uptake and translocation of Zr in B. napus genotypes. ICPOES was also performed to quantify Zr levels in various plant organs. Data from the ICPOES revealed varying patterns of uptake and translocations between Garnet and Agamax. These patterns were similarly shown in IVIS Lumina images, tracing the transport of QD/Zr conjugates. This method ultimately proved to be successful in tracing the uptake of Zr, and could essentially be a useful tool for targeting and imaging a number of other molecules.
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Kunikowska, Grazyna Maria. "Alterations of antioxidant enzymes following manipulations of basal ganglia : relevance to the pathogenesis of Parkinson's disease." Thesis, King's College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313737.
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Roberts, Blaine R. "Structural studies of the antioxidant defense enzymes : copper, zinc superoxide dismutase and alkyl hydroperoxide reductase flavoprotein /." Connect to this title online, 2007. http://hdl.handle.net/1957/5054.
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Xing, Yu. "Mitogen activated protein kinase cascades mediate the regulation of antioxidant enzymes under abiotic stresses in arabidopsis." HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/834.
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Corrêa, Telma Angelina Faraldo. "Comparação da capacidade antioxidante de torras de café e seus efeitos sobre fatores de risco cardiovascular em indivíduos saudáveis." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-03102012-145708/.
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O café, rico em substâncias bioativas, está entre os maiores contribuintes para a ingestão de antioxidantes em vários países. O tipo de torra dos grãos influencia em sua atividade antioxidante. Estudos indicam que o consumo moderado de café filtrado está envolvido na redução do risco de doenças crônicas não-transmissíveis, geralmente associadas entre si e que se constituem em graves problemas de saúde pública. Entretanto, a literatura não apresenta consenso sobre a ação benéfica do café na redução do risco destas doenças. Objetivos: Comparar a atividade antioxidante de dois graus de torras de café (torra média-clara e média) e seus efeitos sobre biomarcadores de risco cardiovascular em indivíduos saudáveis. Métodos: A caracterização de antioxidantes nas bebidas foi realizada pelas análises de compostos fenólicos totais, perfil de ácidos fenólicos, cafeína, melanoidinas e capacidade antioxidante total - TAC (sequestro do radical DPPH e capacidade de absorbância do radical oxigênio - ORAC). Após 1 semana de washout, vinte voluntários saudáveis (20 a 65 anos) ingeriram café filtrado preparado com torra média-clara ou torra média por 4 semanas e com o outro tipo de torra por mais 4 semanas em um ensaio clínico randomizado do tipo crossover, o qual durou 9 semanas. Lipídeos plasmáticos, lipoproteína (a), homocisteína total, biomarcadores glicêmicos e pressão arterial de 24 horas foram medidos antes do período de intervenção a após a ingestão de cada torra. A atividade antioxidante foi avaliada no plasma e em eritrócitos respectivamente pela TAC (kit Total Antioxidant Status e ORAC) e da atividade das enzimas antioxidantes (superóxido dismutase - SOD, glutationa peroxidase - GPx e catalase - CAT). A capacidade de inibição da peroxidação lipídica foi avaliada no plasma pelas determinações de lipoproteínas de baixa densidade (LDL) oxidadas e 8-isoprostano. Biomarcadores inflamatórios relacionados à disfunção endotelial foram medidos no plasma por imunoensaios. Resultados: Vinte voluntários saudáveis (49,5 + 8,9 anos) foram avaliados. A torra média-clara apresentou maior teor de ácidos clorogênicos (334 mg/150 mL; p < 0,001) e menor teor de cafeína (231 mg/150 mL; p = 0,003) que a torra média (210 mg/150 mL e 244 mg/150 mL, respectivamente). Os teores de melanoidinas foram significamente maiores na torra média (p < 0,001). A TAC não diferiu entre as bebidas. A ingestão de ambas as torras causou aumento nas concentrações de colesterol total e LDL (10 e 12 por cento para a torra média-clara; 12 por cento e 14 por cento para a torra média) (p < 0,05). A ingestão da torra média também aumentou a concentração da lipoproteína de alta densidade (HDL) em 7 por cento (p = 0,003). Houve aumento nos índices de Castelli após o consumo da torra média-clara (5 por cento no índice I; p = 0,01 e de 6 por cento no índice II; p = 0,03). O TAS dos indivíduos aumentou 21 por cento e 26 por cento , respectivamente, após consumo da torra média-clara e média (p < 0,001). Os indivíduos também tiveram aumento de 13 por cento e 13 por cento na atividade da CAT, 52 por cento e 75 por cento na SOD e 62 por cento e 49 por cento na GPx após a ingestão da torra média-clara e torra média (p < 0,001), respectivamente. Ambas as torras aumentaram as concentrações da molécula de adesão celular vascular-1 solúvel (sVCAM-1), sendo 18 por cento para a torra média-clara e 14 por cento para a torra média) (p < 0,05). A concentração de fibrinogênio plasmático aumentou 8 por cento após ingestão da torra média (p = 0,01) e a selectina-E solúvel (sE-selectina) aumentou 12 por cento após a torra média-clara (p = 0,02). Embora o consumo de café tenha elevado os níveis de colesterol total e LDL, não se relacionou à alteração de homocisteína total, lipoproteína (a) e biomarcadores de diabetes e de peroxidação lipídica. Conclusão: O consumo moderado de café filtrado apresentou alguns efeitos maléficos sobre o perfil de risco cardiovascular em indivíduos saudáveis, independente de sua atividade antioxidanteIntroduction: Coffee is rich in bioactive substances and it is among the major contributors to the total antioxidant ingestion in several countries. The roasting degree of coffee is important for its antioxidant activity. Studies indicate that the moderate consumption of filtered coffee is involved in the prevention of chronic diseases, which are usually associated and constitute serious problems of public health. However, literature does not present consensus about the beneficial effects of coffee in the prevention of these diseases. Objectives: To compare the antioxidant activity of the two coffee roasts (medium light and medium roast) and their effects on biomarkers of the cardiovascular risk in healthy volunteers. Methods: The antioxidant characterization of the coffee beverages was performed by the total phenolic content analysis, phenolic profile, caffeine, melanoidins and total antioxidant capacity - TAC (DPPH radical scavenging capacity and Oxygen radical absorbance capacity - ORAC assays). After 1-week washout, twenty healthy volunteers (20 to 65 years old) consumed medium light roast or medium roast paperfiltered coffee for 4 weeks and then switched to the other roast for an additional 4 weeks in a randomized crossover trial that lasted 9 weeks. Plasma lipids, lipoprotein (a), total homocysteine, serum glycemic biomarkers, and twenty-four hours blood pressure were measured at baseline and after each intervention. Levels of total antioxidant status (TAS) and ORAC were evaluated in plasma, and antioxidant enzymes activities (superoxide dismutase - SOD, glutathione peroxidase - GPx and catalase - CAT) in erythrocytes. Lipid peroxidation inhibition capacity was determined in plasma by oxidized LDL and 8-isoprostane assays. Endothelial dysfunction-related inflammation biomarkers were measured in plasma by immunoassays. Results: Twenty healthy volunteers (49.5 + 8.9 years) were evaluated. Medium light roast coffee showed higher chlorogenic acids (334 mg/150 mL; p < 0.001) and less caffeine (231 mg/150 mL; p = 0.003) than medium roasting (210 mg/150 mL and 244 mg/150 mL, respectively). Melanoidins were significant higher in medium roast than medium light roast (p < 0.001). There was an increase in the Castelli indexes after medium light roast consumption (5 per cent in the index I; p = 0.01, and 6 per cent in the index II; p = 0.03). No significant differences were observed for TAC between the medium light roast and medium roast. Both roasts increased plasma total cholesterol and LDL concentrations (10 per cent , and 12 per cent for medium light roast; 12 per cent , and 14 per cent for medium roast, respectively) (p < 0.05). Medium roast also increased HDL concentration by 7 per cent (p = 0.003). Compared with baseline, subjects had an increase of 21 per cent and 26 per cent in TAS, 13 per cent and 13 per cent in CAT, 52 per cent and 75 per cent in SOD, and 62 per cent and 49 per cent in GPx after medium light and medium roast consumption (p < 0.001), respectively. Both roasts increased soluble vascular cell adhesion molecule-1 (sVCAM-1) concentrations (18 per cent for medium light roast and 14 per cent for medium roast) (p < 0.05). Plasma fibrinogen concentration increased 8 per cent after medium roast intake (p = 0.01), and soluble E-selectin (sE-selectin) increased 12 per cent after medium light roast intake (p = 0.02). Although coffee beverages have increased total cholesterol and LDL levels, they were not related to elevation in total homocysteine, lipoprotein (a), and biomarkers of diabetes and lipid peroxidation. Conclusion: Moderate paper-filtered coffee consumption may have some undesirable impact on cardiovascular risk in healthy subjects regardless of its antioxidant content.
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Wartha, Elma Regina Silva de Andrade. "Propriedades antioxidantes de clones do pedúnculo de Anacardium occidentale L.: feito sobre a lipoperoxidação e enzimas participantes do sistema antioxidante de defesa do organismo animal." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-08062017-112859/.
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Os compostos fenólicos são substâncias amplamente distribuídas no reino vegetal, em particular nas frutas e em outros vegetais. Estes compostos, destacando-se flavonoides e os ácidos fenólicos, devido à estrutura molecular, podem apresentar a capacidade de inibir processos oxidativos. Além do mais, estão relacionados com a redução de risco de doenças crônicas não transmissíveis tais como: cardiovasculares, câncer, aterosclerose, entre outras. Considerando a elevada produção de caju em território brasileiro e a possibilidade da existência de compostos com potencial antioxidante no pedúnculo de caju , este trabalho teve por objetivo avaliar quantitativa e qualitativamente os compostos fenólicos, particularmente os ácidos fenólicos, e identificar a participação destes em processos metabólicos do organismo animal. Foram caracterizados quimicamente três clones distintos de pedúnculos de caju (CCP-76, CCP-09, BRS-189 e CCP-76 tratado) e na análise química, apresentaram um elevado teor de ácidos graxos monoinsaturados, predominando o ácido oléico, e de fenólicos totais. Os ácidos fenólicos identificados foram: gálico, protocatecuíco, p-cumárico, ferúlico, caféico e salicílico. Foram obtidos extratos aquoso (EAq) e alcoólico (EAlc) e frações de ácidos fenólicos a partir dos pedúnculos e, avaliados em sistemas modelo β-caroteno/ácidolinoléico e em Rancimat. As frações de ácidos fenólicos exibiram expressiva atividade antioxidante no primeiro sistema e os extratos, no segundo, demonstraram fatores de proteção superior ao antioxidante sintético BHT. Pôde-se também verificar a capacidade antioxidante dos extratos e frações do clone CCP-76 no sistema de varredura do radical DPPH. Em ensaio experimental com ratos, em condição normal, foi administrado EAq (80 e 240 mg/kg, v.o.) ou fração de ácidos fenólicos livres (40 e 120 mg/kg, v.o.) obtidos do pedúnculo de caju CCP-76. Neste estudo, não se observou potencialização de todos os antioxidantes enzimáticos (superóxido dismutase, catalase e glutationas peroxidase e redutase), contudo pôde-se verificar a redução dos níveis de lipoperoxidação no tecido cerebral dando indícios de aumento do estado antioxidante nos animais. Também foi avaliado o potencial antioxidante do EAq e da fração de ácidos fenólicos livres sobre o dano hepático em ratos tratados com tetracloreto (CCl4) de carbono. A administração deste teve seu efeito corroborado pela avaliação dos parâmetros bioquímicos, ou seja, aumento exacerbado das enzimas hepáticas no plasma: alanina transaminase (ALT) e aspartato transaminase (AST); decréscimo da atividades da enzimas antioxidantes no fígado e elevação da produção de peróxidos lipídicos no tecido hepático. Nos ratos que receberam EAq (480 mg/kg, v.o.) não se observou alteração comparando-os aos animais tratados apenas com CCl4 . No entanto, a administração de fração de ácidos fenólicos livres, nas duas doses (40 e 120 mg/kg, v.o.), evidenciou pronunciado efeito contra a lesão hepática, com níveis reduzidos de AL T e AST plasmáticas, aumento da atividade das enzimas antioxidantes no fígado e prevenindo a lipoperoxidação hepática mediada pelo radical CCl3• a partir do CCl4. Estudos histológicos do tecido hepático confirmaram as avaliações bioquímicas exibindo preservação tecidual, supressão de degeneração vacuolar macro e microgoticular e de sinais necróticos nos ratos tratados com a fração de ácidos fenólicos livres do pedúnculo de caju.Phenolic compounds are widely distributed in the plant kingdom, particularly fruits and vegetables. Due to their chemical structure, these compounds, in particular flavonoids and phenolic acids, are able to inhibit oxidative processes. Furthermore, can be used to reduce the risk of non-transmissible chronic diseases such as cardiovascular diseases, cancer and atherosclerosis. Taking into consideration the large production of cashew in Brazil and the possible existence of potentially antioxidant compounds present in the cashew apples, the aim of this study was to quantitatively and qualitatively evaluate the presence of phenolic compounds in cashew apple, particularly phenolic acids, and identify their role in metabolic processes in animals. The cashew apples of three distinct clones (CCP-76, CCP-09, BRS-189 and CCP-76 (processed)) were studied. The determination of fatty acids yielded a high concentration of monounsaturated fatty acids, mainly oleic acid, and of total phenolic compound. The phenolic acids found were: gallic, proteocatechuic, p-cumaric, ferulic, caffeic and salicylic acids. Both aqueous (EAq) and ethanolic (EAlc) extracts and phenolic acid fractions were obtained from the cashew apples and were evaluated in a β-carotene/linoleate model system and Rancimat test. The phenolic acid fractions presented an expressive antioxidant activity in the β-carotene/linoleate model system and the extracts, by the Rancimat test presented a protection factor higher than that of antioxidant additive, BHT. We also observed the antioxidant capacity of the extracts and fractions of the CCP-76 clone in the DPPH radical scavenging assay. In an experimental assay with rats, the EAq (80 and 240 mg/kg) or the free phenolic acid fraction (40 and 120 mg/kg) obtained from the cashew apple of CCP-76 clone was administered via the oral route. In this study, the enhancement of enzymatic antioxidants (superoxide dismutase, catalase, glutathione peroxidase and reductase) was not observed, nevertheless, a decrease in the amount of lipoperoxidation in the brain tissue was observed, suggesting that the ingestion of cashew might increase the antioxidative state in animals. Also, the antioxidant activity of EAq and of the free phenolic acid fraction from the cashew apple of CCP-76 clone was verified on the liver damage induced by carbon tetrachloride. The liver damage caused by the administration of carbon tetrachloride was detected by biochemical parameters, namely, the increase in the serum concentrations of alanine transaminase (ALT) and aspartate transaminase (AST) as well as a decrease in the activities of antioxidant enzymes and an increase in peroxidation in the liver. Rats who received EAq (480 mg/kg, p.o.) did not present alterations in any of the parameters evaluated, compared to the animals treated with carbon tetrachloride. On the other hand, the administration of free the phenolic acid fraction in doses of 40 and 120 mg/kg, p.o., had a pronounced effect in protecting against hepatic lesion, which was evidenced by the decrease in plasma ALT and AST, enhancing the activity of antioxidant enzymes and preventing lipoperoxidation mediated by the CCl3• radical generated by carbon tetrachloride. Histological studies were able to confirm the biochemical alterations observed in that the liver tissue obtained from rats treated with phenolic acid fractions extracted from cashew apple of CCP-76 clone presented a preserved tissue structure and suppression of macro and microgoticular vacuolar degeneration as well as of signs of necrosis.
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Sousa, Kellina Oliveira de. "Qualidade e metabolismo antioxidante no desenvolvimento de frutos de clones de aceroleira." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8479.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoO fruto da aceroleira (Malpighia emarginata D.C.) apresenta potencial jà consolidado para industrializaÃÃo uma vez que à consumido sob forma de sucos, utilizada no enriquecimento de produtos alimentÃcios e na forma de nutracÃuticos. O amadurecimento de frutos à um processo complexo do desenvolvimento, envolvendo inÃmeras mudanÃas nas caracterÃsticas bioquÃmicas, fisiolÃgicas e sensoriais, bem como no metabolismo oxidativo determinando seus atributos de qualidade e propriedade antioxidante. Desta forma, esse trabalho estudou as alteraÃÃes nos metabÃlitos antioxidantes e na capacidade antioxidante total de frutos de diferentes clones de aceroleira durante o seu desenvolvimento e amadurecimento. Os frutos de clones de aceroleira, FS, FB e BRS 366, foram analisados em diferentes estÃdios do desenvolvimento quanto Ãs variÃveis de qualidade pÃs-colheita, compostos antioxidantes, atividade antioxidante total (AAT) e atividade das enzimas antioxidantes. Durante o processo de desenvolvimento dos frutos da aceroleira o conteÃdo de sÃlidos solÃveis aumentou, principalmente nos frutos do clone de aceroleira FS, o conteÃdo de vitamina C e de polifenÃis extraÃveis totais (PET) diminuiu resultando em um declÃnio da atividade antioxidante dos frutos. A atividade das enzimas antioxidantes dismutase do superÃxido (SOD), catalase (CAT) e peroxidase do ascorbato (APX) diminuiu ao longo do amadurecimento dos frutos. O amadurecimento dos frutos estados foi acompanhado por um aumento do estresse oxidativo, o qual pode contribuir para as alteraÃÃes observadas na qualidade pÃs-colheita dos frutos e para um declÃnio em seu potencial antioxidante.
Acerola (Malpighia emarginata DC) has already established the potential for industrialization since it is consumed in the form of juices and jellies, used in the enrichment of food products and as nutraceuticals. The fruit ripening is a complex process of development, involving numerous changes in the biochemical, physiological and sensory as well as in oxidative metabolism by determining its quality attributes and antioxidant properties. This research was to study changes in antioxidant metabolites and total antioxidant capacity of fruits of different clones of acerola during development and maturation. Acerola fruits, FS, FB and BRS 366, were analyzed at different maturity stages for quality parameters post-harvest, antioxidant compounds, total antioxidant activity (TAA) and antioxidant enzymes activity. During the development of acerola soluble solids content increased, especially in the fruits of acerola clone FS, the vitamin C content and total extractable polyphenols (TEP) decreased resulting in a decline in antioxidant activity of fruits. The activities of oxygen-scavenging enzymes superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) decreased during the ripening of fruits. The maturation of the tropical species studied was accompanied by an increased oxidative stress, which may contribute to the observed changes in the postharvest quality of fruit and a decline in their antioxidant potential.
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Unfer, Taís Cristina. "Influência de estrógenos e progestinas sobre a atividade da superóxido dismutase e o estatus oxidativo em mulheres." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/3841.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorThe deficit of estrogen that accompanies menopause may be involved in the metabolic changes and increased oxidative stress during non-reproductive female life. Hormone replacement therapy (HRT) has been used to attenuate the menopausal symptoms. It is prescribed either as the replacement of estrogen alone or the combination of estrogen with progestins. Superoxide dismutase (SOD) is a key enzyme in the control of reactive oxygen species levels and SOD modulators may have potential use as therapeutic agents in oxidative stress-associated disorders. The objectives of this study were to evaluate: i) the effects of natural and synthetic estrogens and progestins on the activity of SOD from human blood in vitro; and ii) the effect of the hormone therapy with estrogen or estrogen plus progestin on the markers of oxidative stress in the blood of postmenopausal women and the relationship among these markers and the serum levels of estradiol and progesterone. The in vitro effect of steroid hormones (17 β-estradiol 17-acetate, progesterone, β-estradiol 3-benzoate and medroxyprogesterone 17-acetate) was evaluated in the enzyme purified from human erythrocytes (CuZnSOD) (Sigma) and in samples of erythrocytes (cytosolic CuZnSOD) and platelets-rich plasma (PRP) (MnSOD and cytosolic and extracellular CuZnSOD) obtained from healthy men and women. Hormones caused a dose-dependent stimulation of erythrocyte CuZnSOD activity at low concentrations (physiological), but this effect was abolished at higher concentrations. The combination of an estrogen with a progestin had a synergic effect on the erythrocyte CuZnSOD activity. In the PRP the activity of MnSOD was not affected by hormones, whereas the CuZnSOD activity was modulated only by the natural, but not by the synthetic hormone derivatives. Four groups of women were selected to evaluate blood markers of oxidative stress: premenopausal women (n=24), postmenopausal women without hormone therapy (HT) (n=31), postmenopausal women with estrogen-only HT (ET) (n=12) and estrogen plus progestin HT (EPT) (n=16). The levels of protein carbonyl, lipid peroxidation and the activity of catalase and glutathione peroxidase did not differ among groups. However, the activities of SOD isoforms (CuZn and MnSOD) and total plasma antioxidant power (FRAP) were significantly higher in postmenopausal women under EPT compared with postmenopausal women without HT, whereas ET increased only the activity of CuZnSOD in postmenopausal women. The duration of HT and serum E2 levels were positively correlated with the activity of CuZnSOD and the total antioxidant power of plasma (FRAP levels), whereas progesterone levels were positively correlated with the activity of CuZnSOD and negatively correlated with protein carbonyl levels. The total antioxidant power of plasma was positively correlated to the CuZnSOD activity and to the GPx activity. The present study demonstrated for the first time, that the natural and synthetic steroid hormones have a direct biphasic effect on CuZnSOD activity of human erythrocytes in vitro. We also observed that the hormone replacement therapy increase the antioxidant status of postmenopausal women due to an increase of the enzymatic antioxidant defenses and this effect is more remarkable with the combined hormone therapy (estrogen plus progestin).
O déficit de estrogênio, que acompanha a menopausa pode ser relacionado às alterações metabólicas e ao aumento do estresse oxidativo, observados na fase não reprodutiva feminina. A terapia de reposição hormonal é utilizada para atenuar os sintomas da menopausa. Ela é prescrita como reposição de estrogênio ou uma combinação de estrogênio com progestina. A superóxido dismutase (SOD) é uma enzima chave no controle dos níveis de espécies reativas de oxigênio e, moduladores da SOD podem ser úteis como agentes terapêuticos em desordens associadas ao estresse oxidativo. Os objetivos deste estudo foram avaliar: i) os efeitos, in vitro, de estrógenos e progesterona, naturais e sintéticos, sobre a atividade da SOD presente em sangue humano, e ii) o efeito da terapia hormonal com estrogênio ou estrogênio mais progestinas sobre os marcadores de estresse oxidativo no sangue de mulheres na pós-menopausa e a relação entre esses marcadores e os níveis séricos de estradiol e progesterona. O efeito, in vitro, de hormônios esteroides (acetato de 17β-estradiol (E2), progesterona, 3-benzoato de 17β-estradiol e 17-acetato de medroxiprogesterona) foi avaliado na enzima purificada a partir de eritrócitos humanos (CuZnSOD) (Sigma), e em amostras de eritrócitos (CuZnSOD citosólica) e de plasma rico em plaquetas (PRP) (CuZnSOD, citosólica e extracelular, e MnSOD, mitocondrial), obtidas a partir de homens e mulheres saudáveis. Os hormônios, em concentrações baixas (fisiológica), causaram uma estimulação, dose dependente, da atividade da CuZnSOD eritrocitária, embora, este efeito tenha sido suprimido em concentrações mais elevadas. Ademais, a combinação de um estrogênio com uma progestina apresentou um efeito sinérgico sobre a atividade da CuZnSOD eritrocitária. No PRP a atividade da MnSOD não foi afetada por hormônios, enquanto que a atividade da CuZnSOD foi modulada apenas pelos esteroides naturais. Quatro grupos de mulheres foram selecionados para avaliar marcadores sanguíneos de estresse oxidativo: mulheres na pré-menopausa (n = 24), mulheres na pós-menopausa sem terapia hormonal (TH) (n = 31), mulheres na pós-pausa utilizando TH, composta apenas de estrogênio (ET) (n = 12), ou de uma combinação de estrogênio mais progestinas (EPT) (n = 16). Os níveis de proteína carbonilada, peroxidação lipídica e da atividade de catalase e glutationa peroxidase (GPx) não diferiram entre os grupos. No entanto, as atividades das isoformas da SOD (CuZn e MnSOD) e o poder antioxidante total do plasma (FRAP) foram significativamente maiores em mulheres na pós-menopausa sob EPT em comparação com mulheres na pós-menopausa sem TH, enquanto que a ET aumentou apenas a atividade da CuZnSOD em mulheres na pós-menopausa. A duração da TH e os níveis séricos de E2 foram positivamente correlacionados com a atividade da CuZnSOD e com o poder antioxidante total do plasma (FRAP), enquanto que os níveis de progesterona foram positivamente correlacionados com a atividade da CuZnSOD e negativamente correlacionados com os níveis de proteína carbonilada. O poder antioxidante total do plasma foi positivamente correlacionada com a atividade da CuZnSOD e da GPx. O presente estudo demonstrou, pela primeira vez, que os hormônios esteroides, naturais e sintéticos, têm um efeito direto e bifásico na atividade da CuZnSOD eritrocitária humana in vitro. Também foi observado que a terapia de reposição hormonal aumenta a capacidade antioxidante de mulheres na pós-menopausa devido a um aumento das defesas antioxidantes enzimáticas (SODs) e que este efeito é ainda mais pronunciado com o uso de terapia hormonal combinada (estrogênio e progestinas).