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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Estabiliza??o de mol?culas bioativas presentes em suco de camucamu (Myrciaria d?bia (H.B.K) Mc Vaugh) pela integra??o dos processos de osmose inversa, evapora??o osm?tica e atomiza??o / Stabilization of bioactive molecules present in camucamu juice by means of interaction among the processes of reverse osmosis, osmotic evaporation and atomization

Souza, Andr? Luis Rodrigues 06 March 2012 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-04-27T13:51:34Z No. of bitstreams: 1 2012 - Andr? Luis R. de Souza.pdf: 1971622 bytes, checksum: 5237bc23d365c59e774d9f8776efabf1 (MD5) / Made available in DSpace on 2017-04-27T13:51:34Z (GMT). No. of bitstreams: 1 2012 - Andr? Luis R. de Souza.pdf: 1971622 bytes, checksum: 5237bc23d365c59e774d9f8776efabf1 (MD5) Previous issue date: 2012-03-06 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Camu-camu is a native fruit from the Amazonian region, cultivated in the margins of rivers, lakes and Amazonian creeks called igarap?s. It is known as one of the fruit with the highest content of vitamin C. Reverse osmosis is a membrane concentration process in which the applied pressure is higher than the juice osmotic pressure. Such process favors the solvent permeation from the region with the highest concentration to the one with the lowest. Osmotic evaporation is another membrane concentration process in which a porous hydrophobic membrane separates the solution that is going to be concentrated from a concentrate brine solution. Microencapsulation is the process in which an active agent is entrapped by means of a polymer cover. Such process promotes the release of these active agents under specific conditions. The aim of this work is to evaluate the use of membrane separation processes and microencapsulation for the processing of camu-camu fruits. The camu-camu pulp, which has been obtained through the depulping of camu-camu fruits, was first centrifuged, in order to decrease its suspended solids content, and clarified by microfiltration with polysulfone membranes. Six clarification processes have carried out at 2.5 bar transmembrane pressure and 45?C. The clarified juice was concentrated by reverse osmosis at 60 bar and 20 ?C. The avarage permeate flux has been of 11.3 L/hm2. The preconcentrated juice had 28.8?Brix and the concentration degree of the process was 3.8. The pre-concentrated juice has been concentrated by osmotic evaporation in a laboratorial system with polytetrafluoroethylene membrane. The process presented an average pemeate flux of 2.4 Kg/hm2. The soluble solids content of the concentrated juice was of 56.6 ?Brix, presenting a concentration degree of 1.98. The retentate fraction of the microfiltration process was microencapsulated in a spray dryer. Three encapsulation agents were evaluated: starch, maltodextrin and the mixture of both. The values presented for the physicochemical caracterization of the pre-concentrated and concentrated camu-camu juices indicate that there has been an increase both in the physical characteristics of the juice, such as soluble solids, total solids and acidity, and in the concentration of camu-camu bioactive compounds. The dehydrated camu-camu juice presented a high concentration of bioactive substances. Nevertheless, there has been no stability of such compounds during storage. Through the results obtained in the present work, it is possible to observe that the integration of membrane processes proved efficient in the concentration of camu-camu juice, with a final product of high nutritional value / O camu-camu ? um fruto nativo da regi?o amaz?nica, cultivado as margens de rios, lagos e igarap?s. ? reconhecido como um dos frutos com um dos maiores teores de vitamina C. Osmose inversa ? o processo de concentra??o por membranas onde a press?o aplicada ? maior que a press?o osm?tica do suco, favorecendo a permea??o do solvente da regi?o de maior concentra??o para regi?o de menor concentra??o. Evapora??o osm?tica ? um outro processo de concentra??o, onde uma membrana hidrof?bica porosa separa a solu??o que ser? concentrada e uma salmoura concentrada. A microencapsula??o ? o processo onde um agente ativo ? protegido por meio de uma cobertura de pol?meros, ocorrendo a libera??o desses agentes ativos em condi??es espec?ficas. O objetivo desta disserta??o foi avaliar o uso dos processos de separa??o com membranas e microencapsulamento para o processamento de suco de camu-camu. Os frutos de camu-camu foram despolpados, sendo o suco submetido a centrifuga??o, com o objetivo de reduzir os s?lidos em suspens?o, e posteriormente clarificado por microfiltra??o em um sistema de membranas de polissulfona. Foram realizados seis processos de clarifica??o a 2,5 bar e 45?C. O suco clarificado foi pr?-concentrado por osmose inversa a 60 bar e 20 ?C. O fluxo permeado m?dio foi de 11,3 L/hm2. O suco pr?-concentrado apresentou teor de s?lidos sol?veis de 28,8?Brix e grau de concentra??o de 3,8. O suco pr?-concentrado foi processado por evapora??o osm?tica em um sistema laboratorial constitu?do por membranas de politetrafluoretileno. O processo apresentou fluxo m?dio permeado de 2,4 kg/hm2. O teor de s?lidos sol?veis do suco concentrado foi de 56,6 ?Brix, apresentando um grau de concentra??o de 1,98. O processo de microencapsula??o da fra??o retida do suco de camucamu foi realizado em um spray dryer Buchi Modelo B-190. Foram realizados tr?s ensaios com tr?s formula??es diferentes: mistura entre amido e maltodextrina, somente amido e somente maltodextrina. Os valores apresentados para a caracteriza??o f?sico-qu?mica do suco de camu-camu pr?-concentrado e concentrado indicam que houve um aumento nos s?lidos sol?veis e totais e da acidez, bem como no teor das subst?ncias bioativas do camucamu. O suco de camu-camu desidratado apresentou alto teor de subst?ncias bioativas, onde a estabilidade desses compostos durante o per?odo de armazenamento n?o foi alcan?ada. Observa-se que a integra??o dos processos com membranas se mostrou eficaz na concentra??o do suco de camu-camu, obtendo um produto com alta qualidade nutricional.
272

Efeitos do ácido ascórbico nos biomarcadores de estresse oxidativo induzido por exercício físico exaustivo / Effects of ascorbic acid on oxidative stress biomarkers induced by exhaustive exercise

Picchi, Monike Garlipp 18 May 2015 (has links)
O objetivo deste estudo foi avaliar os efeitos da suplementação de vitamina C nos biomarcadores de estresse oxidativo induzido por exercício físico exaustivo. A amostra foi composta por 13 indivíduos do sexo masculino, fisicamente ativos, com idades entre 18 e 33 anos, IMC médio 23,65 ± 3,5 kg/m² e VO2max de 50,94 ± 5,2 ml.kg-1.min-1. Estes indivíduos foram submetidos a um protocolo de exercício exaustivo (40 minutos de corrida a 70-75% do VO2max, e aumento da velocidade para 90% do VO2max até a exaustão), randomizados duplo cego em duas fases (placebo X vitamina C). Na fase vitamina C eles ingeriram 500 mg de vitamina C por dia, durante 7 dias, antes do protocolo exaustivo, e na fase placebo eles ingeriram por sete dias placebo antes do mesmo protocolo. Foram coletadas amostras de sangue antes do exercício, logo após, 1h, 2h, 4h e 24h após para determinação dos biomarcadores de estresse oxidativo. As duas fases foram homogêneas, os indivíduos apresentaram consumo alimentar similar e não houve diferença na duração e intensidade do exercício. Os resultados mostram que o uso de suplemento de vitamina C favoreceu maiores níveis séricos de ácido ascórbico em relação ao placebo logo depois do exercício até 4 horas após, e por isso poupou a eliminação dos outros antioxidantes, -tocoferol e retinol, que estavam em menores concentrações séricas até 2 horas após o exercício, e do GSH, que se manteve em menores concentrações até 24 horas após. Enquanto com uso de placebo, já que os níveis de ácido ascórbico eram menores, houve uma maior liberação destes outros antioxidantes, e o -tocoferol e retinol começaram a ser consumidos 1 hora após o exercício, para combater os radicais livres formados, até 24 horas após. Apesar da CAT não ser alterada nem pela suplementação nem pelo exercício exaustivo, o FRAP foi maior na fase vitamina C e se manteve estável nas 24h após o exercício. O ácido úrico não apresentou diferença significativa, e seu uso foi poupado por outros antioxidantes séricos nas duas intervenções. Nas duas fases os indivíduos conseguiram combater os radicais livres formados pelo exercício exaustivo, já que os marcadores de peroxidação lipídica (MDA, TBARS e FOX) não aumentaram após o exercício em nenhuma das intervenções, não houve aumento de oxidação protéica (AOPP e PC). Os marcadores de lesão hepática (TGO), lesão muscular (CK) e tecidual (LDH) se comportaram de maneira igual com ou sem uso de vitamina C. As vantagens do uso adicional de vitamina C são: a maior proteção antioxidante desde o ínicio do exercício, já que apresenta maiores concentrações séricas de vitamina C e de FRAP, o menor grau de peroxidação lipídica, avaliado pelo MDA, o menor grau de oxidação protéica, avaliado pelas PC e a menor dependência do GSH como antioxidante endógeno. Sendo assim, uso de uma dose modesta de vitamina C, por um curto período de tempo, foi capaz de auxiliar na proteção antioxidante, sem nenhum efeito danoso aos indivíduos. / The objective of this study was to evaluate the effects of vitamin C supplementation on oxidative stress biomarkers induced by exhaustive exercise. The sample consisted of 13 males, physically active, aged 18 to 33 years, mean BMI 23.65 ± 3.5 kg/m² and 50.94 ± 5.2 VO2max ml.kg-1. min-1. These individuals were subjected to an exhaustive exercise protocol (40 minutes of running at 70-75% of VO2max, and increased speed to 90% VO2max until exhaustion), randomized double-blind in 2 phases (placebo X vitamin C). In vitamin C phase they ingested 500 mg vitamin C per day for 7 days before exhausting protocol and the placebo phase, they ingested placebo for 7 days prior to the same protocol. Blood samples were taken before exercise, immediately after, 1h, 2h, 4h and 24h after for determination of biomarkers of oxidative stress. The two phases were homogeneous, the subjects had similar food consumption and no difference in the duration and intensity of exercise. The results show that the use of vitamin C supplement favored higher serum levels of ascorbic acid relative to placebo soon after exercise to 4 hours after, and therefore spared the elimination of other antioxidants, -tocopherol and retinol, which were lower serum concentrations up to 2 hours after exercise, and GSH, which remained at lower levels within 24 hours. As with the use of placebo, as the ascorbic acid levels were lower, there was a greater release of these other antioxidants, and -tocopherol and retinol began to be consumed in 1 hour of exercise to combat free radicals formed by 24 hours. Despite the CAT not be altered or by supplementation or by exhaustive exercise, the FRAP was higher in vitamin C phase and remained stable in the 24 hours after exercise. Uric acid showed no significant difference, and its use has been spared by other serum antioxidants in 2 interventions. In 2 phases individuals able combat free radicals formed by exhaustive exercise, since the lipid peroxidation markers (MDA, TBARS and FOX) did not increase after exercise in any of the interventions, there was no increase in protein oxidation (AOPP and PC) . The markers of liver injury (AST), muscle damage (CK) and tissue (LDH) behaved equally with or without use of vitamin C. The advantages of the additional use of vitamin C are: the highest antioxidant protection since the beginning of exercise, since it has higher serum concentrations of vitamin C and FRAP, the lowest degree of lipid peroxidation, measured by MDA, the lowest level of protein oxidation, rated by PC and less dependent on GSH as an endogenous antioxidant. Thus, use of a modest dose of vitamin C, for a short period of time, was able to assist in antioxidant protection, with no harmful effect on individuals.
273

Experimental and Clinical Studies of Oxidative Stress in Pre-Eclampsia

Nash, Peppi January 2007 (has links)
<p>Impaired placentation and oxidative stress are proposed to play major roles in the pathogenesis of pre-eclampsia (PE). It has recently been pointed out that PE might be more than one disease and may have several different pathogeneses. This thesis describes a new animal model for PE and examines the role of oxidative stress in early respective late onset PE. </p><p>The effects of Suramin injections on day 10 and 11 of pregnancy were investigated in normal and diabetic rats of two strains (U and H), with or without additional vitamin E treatment. Suramin caused placental dysfunction in both rat strains: foetal growth restriction, increased resorption rate, reduced placental blood flow, and decreased maternal blood volume in the placenta. In the U strain Suramin also caused maternal hypertension and reduced renal blood flow. Oxidative stress in the Suramin treated rats was indicated by increased levels of isoprostane 8-iso-PGF<sub>2α</sub> in the placenta. Antioxidative treatment with vitamin E partly protected against the effects of Suramin. Streptozotocin-induced diabetes seemed to cause similar placental effects as Suramin, and in the diabetic rats the additional effects of Suramin were only moderate. In conclusion, Suramin-injected pregnant rats constitute a valid animal model for placental dysfunction (U and H rats) and PE (U rats). </p><p>Oxidative stress was estimated in women with early onset (≤ 32 weeks) or late onset (≥ 35 weeks) PE, in normotensive pregnant women of respective gestational length, and in healthy non-pregnant women. The ratio of PAI-1/PAI-2 was measured in serum, and the amount of isoprostane 8-iso-PGF<sub>2α</sub> was measured in placenta, serum, and urine. The ratio of PAI-1/PAI-2 and placental isoprostane levels were higher in women with early onset PE compared with all other groups. Serum levels of isoprostane were similar between groups. Urinary levels of isoprostane were similar in all pregnant women, but lower in non-pregnant women. These data indicate that pregnancy increases general oxidative stress, and that early onset, but not late onset PE, causes increased oxidative stress also in placental tissue. The pathogeneses of early and late onset PE are, therefore, not likely to be identical.</p>
274

Experimental and Clinical Studies of Oxidative Stress in Pre-Eclampsia

Nash, Peppi January 2007 (has links)
Impaired placentation and oxidative stress are proposed to play major roles in the pathogenesis of pre-eclampsia (PE). It has recently been pointed out that PE might be more than one disease and may have several different pathogeneses. This thesis describes a new animal model for PE and examines the role of oxidative stress in early respective late onset PE. The effects of Suramin injections on day 10 and 11 of pregnancy were investigated in normal and diabetic rats of two strains (U and H), with or without additional vitamin E treatment. Suramin caused placental dysfunction in both rat strains: foetal growth restriction, increased resorption rate, reduced placental blood flow, and decreased maternal blood volume in the placenta. In the U strain Suramin also caused maternal hypertension and reduced renal blood flow. Oxidative stress in the Suramin treated rats was indicated by increased levels of isoprostane 8-iso-PGF2α in the placenta. Antioxidative treatment with vitamin E partly protected against the effects of Suramin. Streptozotocin-induced diabetes seemed to cause similar placental effects as Suramin, and in the diabetic rats the additional effects of Suramin were only moderate. In conclusion, Suramin-injected pregnant rats constitute a valid animal model for placental dysfunction (U and H rats) and PE (U rats). Oxidative stress was estimated in women with early onset (≤ 32 weeks) or late onset (≥ 35 weeks) PE, in normotensive pregnant women of respective gestational length, and in healthy non-pregnant women. The ratio of PAI-1/PAI-2 was measured in serum, and the amount of isoprostane 8-iso-PGF2α was measured in placenta, serum, and urine. The ratio of PAI-1/PAI-2 and placental isoprostane levels were higher in women with early onset PE compared with all other groups. Serum levels of isoprostane were similar between groups. Urinary levels of isoprostane were similar in all pregnant women, but lower in non-pregnant women. These data indicate that pregnancy increases general oxidative stress, and that early onset, but not late onset PE, causes increased oxidative stress also in placental tissue. The pathogeneses of early and late onset PE are, therefore, not likely to be identical.
275

Oxidative Damage And Regulation Of Antioxidant Enzymes In Streptozotocin Induced Diabetic Rats

Sadi, Gokhan 01 October 2009 (has links) (PDF)
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&lt / 0.05) in diabetic animals and supplementing the animals either individually or in combination, with two powerful antioxidants DL-&amp / #945 / -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.
276

The Effects Of Streptozotocin Induced-diabetes On Rat Testes And The Recovery Role Of Vitamin C

Guldag, Damla 01 January 2012 (has links) (PDF)
Type I Diabetes is a multisystem disease having both biochemical and structural consequences. It causes alterations in carbohydrate, protein, and fat metabolisms due to hyperglycemia. Type I diabetes is also correlated with increased formation of free radicals and decreased levels of antioxidant potential. Lower endogeneous antioxidant amounts and elevated lipid peroxidation levels in diabetes constitute the basis of risk factors for the development of diabetic complications. These complications lead to irreversible damages in nearly all vital organs and systems. Since the antioxidant capacity lowered in diabetic conditions, it becomes important to be able to use some common antioxidants, as a complementary treatment strategy for diabetes. The effect of type I diabetes and the recovery role of Vitamin C on the structure, composition and function of the macromolecular content of testicular tissue is still unknown. Therefore, in the current study, it was aimed to investigate the alterations in the macromolecules of rat testes due to Streptozotocin (STZ)-induced type I diabetes using Attenuated Total Reflectance (ATR)-Fourier Transform Infrared (FTIR) spectroscopic and FTIR microspectroscopic techniques. Furthermore it was iv aimed to gain useful information about the recovery role of Vitamin C, as an antioxidant, against the diabetic complications. The detailed spectral analysis revealed that, the macromolecular structure and composition of rat testes are highly affected due to the development of diabetes. The lipid and protein content of diabetic rat testes were shown to decrease considerably, indicating an increase in lipolysis and proteolysis processes. Diabetes was also shown to lead to a decrease in the content of fatty acids and nucleic acids. In addition to the compositional alterations, protein conformation, and protein secondary structural components were also found to alter in diabetic state. Besides, lipid peroxidation levels were found to increase, and the elevated levels of lipid peroxidation products end up with increased levels of unsaturation, and also end up with increased levels of disorderness in diabetic conditions. On the other hand, with the administration of Vitamin C, the diabetes-induced alterations were found to be partially recovered, indicating that after more confirmative researches, Vitamin C may have a chance to be used as a complementary therapy in the treatment of diabetes.
277

Effects of arginine, vitamin E and vitamin C on cardiopulmonary function and ascites parameters in broilers exposed to cold temperature

Kawthekar, Sunil Bajirao. January 2007 (has links)
Two identical experiments were conducted to evaluate the combined effects of arginine (AR), vitamin E (VE) and vitamin C (VC) on cardiopulmonary performance and ascites parameters of broilers reared under cold environmental temperature. One d old male broilers were fed a basal corn-soybean meal diet (CTL, 1.2 % AR and 40 IU VE), the basal diet supplemented with 1% AR and either 200 IU VE (AE group), or 500 mg of VC (AC group), or a combination of VE and VC (AEC group) at the same level per kg of feed. Pulmonary arterial pressure (PAP) and mean arterial pressure (MAP) were recorded in clinically healthy anesthetized birds (28-42 d old) before and after an epinephrine challenge (EPI, 0.5 mg/kg BW i.v.), Amino-guanidine Hemisulphate (AG, 100 mg/kg BW i.v.) and N-Nitro L-Arginine Methyl Ester (L-NAME 50 mg/kg BW, i.v.) at 20 min intervals. The PAP increased 30 s after EPI in all birds, but the peak PAP was lower in the AEC group than in all the other birds. After 120 s of challenge the PAP was lower in AEC birds compared to the other birds. The PAP returned to pre-EPI levels within 300 s in all groups. The PAP was increased ( P&lt; 0.05) within 60 s after the AG and L-NAME challenge in all groups, but no differences were found among groups. Plasma nitric oxide (NO) was higher in the AEC birds than in all the other groups before and after challenge. Our results showed that birds fed AEC maintained a lower PAP than the CTL birds after EPI elicited an increase in cardiac output and this can be explained by a higher production of NO. A combination of AR, VE, and VC may have complementary effects against oxidative stress, protecting the endothelium and preserving NO function.
278

Atividade antibacteriana e características químicas e fitoquímicas de Talinum paniculatum (jacq.) gaertn. (major-gomes) / Antibacterial activity and chemical and phytochemical characteristics of Talinum paniculatum (JACQ.) gaertn. (Major-Gomes)

Vieira, Aline Campos January 2014 (has links)
As plantas alimentícias são definidas como plantas que têm uma ou mais partes ou produtos que podem ser empregados na alimentação das pessoas. As espécies comestíveis que não são frequentemente utilizadas, são denominadas plantas alimentícias não convencionais (PANC). A espécie Talinum paniculatum (Jacq.) Gaertn. (Major-Gomes) é considerada uma excelente hortaliça, além de todas as partes da planta serem utilizadas na medicina caseira. Foram realizados testes para avaliar a intensidade de Atividade de Inibição Bacteriana/Bacteriostasia (IINIB) e Intensidade de Atividade de Inativação Bacteriana/Bactericidia (IINAB) do extrato alcoólico de folhas e ramos de Talinum paniculatum utilizados juntos, acessada na cidade de Porto Alegre/RS, sobre os microrganismos padrões ATCC: Enterococcus faecalis (ATCC 19433), Escherichia coli (ATCC 11229), Salmonella Enteritidis (ATCC 13076) e Staphylococcus aureus (ATCC 25923). Também foram realizados testes com as folhas e os ramos de Talinum paniculatum utilizados juntos, para determinar e quantificar: a composição centesimal (umidade, cinzas, carboidratos, proteínas, lipídeos e fibra bruta), em base seca e úmida; minerais em base seca, e polifenóis totais e vitamina C da planta logo após a colheita. Quanto à IINAB, a bactéria mais resistente, foi a Gram-positiva Enterococcus faecalis e a mais sensível foi a Gram-negativa Salmonella Enteritidis. Com relação à IINIB, a bactéria mais resistente, foi a Gram-positiva Staphylococcus aureus e a mais sensível foi a Gram-positiva Enterococcus faecalis. Tanto para IINAB quanto para IINIBI houve diferença significativa entre as bactérias testadas e as concentrações do extrato. Os resultados da composição química de Talinum paniculatum, indicam que esta espécie pode representar um complemento para a alimentação dos seres humanos e fornecer teores consideráveis de macronutrientes e micronutrientes, além de contribuir com o consumo de substâncias bioativas, como a vitamina C, que em 100g de amostra representou mais da metade da ingestão diária recomendada. / The food plants are defined as plants that have one or more parts or products that can be used to feed people. Edible species that are not often used are called unconventional food plants. The species Talinum paniculatum (Jacq.) Gaertn. (Major-Gomes) is an excellent vegetable, and all parts of the plant are used in homemade medicine. Tests were performed to evaluate the intensity of bacterial inhibition activity (IINIB) and the intensity of bacterial inactivation activity (IINAB) of alcoholic extract of stalks and leaves of Talinum paniculatum used together, from Porto Alegre/ RS, confronted with standard inoculum: Enterococcus faecalis (ATCC 19433), Escherichia coli (ATCC 11229), Salmonella Enteritidis (ATCC 13076 ) e Staphylococcus aureus (ATCC 25923). Tests were also conducted with stalks and leaves of Talinum paniculatum used together to determine and quantify: proximal composition (moisture content, ashes content, proteins, lipids and crude fiber, in dry and wet basis; minerals in dry basis and total polyphenols and vitamin C of stalks and leaves of plant soon after harvest. As for IINAB, the Gram-positive bacteria Enterococcus faecalis was the most resistant and the Gram-negative bacteria Salmonella Enteritidis was the most sensitive. With relation to IINIB, the Gram-positive bacteria Staphylococcus aureus was the most resistant and the Gram-positive bacteria Enterococcus faecalis was the most sensitive. For IINAB and IINIB there was a significant difference between the tested bacteria and concentrations of the extract. The results of the chemical composition of Talinum paniculatum indicate that the species can be a food supplement for human beings and can provide considerable levels of macronutrients and micronutrients, furthermore contribute to the consumption of bioactive substances, such as vitamin C that in 100g sample represented more than half of the recommended daily intake.
279

Efeito da Suplementação da Vitamina C em Rações de Crescimento de Piau Três Pintas / Effect of Vitamin C Suplementacion in Rations of Growth of Piau Três Pintas

Silva, Jaqueline Maria da 15 September 2009 (has links)
Made available in DSpace on 2016-08-15T20:31:02Z (GMT). No. of bitstreams: 1 JaquelineMS_DISSERT.pdf: 2290951 bytes, checksum: 3c0b30ce69318be58e028360db5c992e (MD5) Previous issue date: 2009-09-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to evaluate the influence of vitamin C supplementation in the diet of fish species piau três pintas (L. reinhardit), which was held to monitor the performance and yield production, analysis of the nutritional composition (carcass and fillet ), and glycemic parameters. The experiment lasted 90 days (fingerlings/ juvenile). 1040 fingerlings were used, housed in 16 tanks for breeding, with a capacity of 500 liters. The design was randomized blocks with four treatments and four replications, and the control diet was designed to meet the requirement of vitamin C as trade recommendations and other diets were prepared to contain levels of extra dietary supplementation of vitamin C (250; 500 and 750 mg ascorbic acid / kg diet). For the analysis of the nutritional composition were used 6 fish per experimental unit. All diets were isonitrogenous and isocaloric (28% PB and 3100 kcal / kg diet). No effect was observed significant regression in performance and glycemic parameters in supplementation levels of vitamin C. However, the fillet yield linearly decreasing the effect of treatments (&#1088;<0.05). Regarding the chemical composition of nutritional was observed in effect response to significant levels of supplementation and in some cases equating to the control. Thus, we observed increased linearly on the concentration of mineral matter (&#1088;<0.05) and decreasing trend for levels of energy rude (&#1088;<0.05). Therefore, it is concluded that the conditions of this work, the inclusion of vitamin C in commercial level was sufficient to provide productive performance benefits for chemical composition and nutritional stress reduction management and harvesting, equal to those diets that were supplemented / O objetivo deste estudo foi avaliar a influência da suplementação de vitamina C na dieta de peixes da espécie piau três pintas (L. reinhardit), no qual realizou-se o monitoramento do desempenho e rendimento produtivo, análise da composição química nutricional (carcaça e filé), bem como parâmetros glicêmicos. O experimento de campo teve duração de 90 dias de (alevino p/ juvenil). Foram utilizados 1040 alevinos, alojados em 16 aquários de criação, com capacidade de 500 litros. O delineamento utilizado foi em blocos casualizados com quatro tratamentos e quatro repetições, sendo que a ração controle foi elaborada para atender a exigência de vitamina C conforme recomendações comerciais e as demais rações foram elaboradas para conter níveis de suplementação extra dietética de vitamina C (250; 500 e 750 mg ácido ascórbico/kg ração). Para as análises da composição química nutricional foram utilizados 6 peixes/unidade experimental. Todas as dietas foram isoprotéicas e isocalóricas (28 % de PB e 3100 kcal/kg de ração). Não observou-se efeito significativo da regressão no desempenho produtivo e parâmetros glicêmicos nos níveis suplementares de vitamina C. No entanto, o rendimento de filé apresentou resposta linear decrescente ao efeito dos tratamentos (&#1088;<0,05). Em relação à composição química nutricional, observou-se efeito-resposta significativo para os níveis de suplementação e em alguns casos equiparando-se ao controle. Assim, foi observado resposta linear crescente sobre os teores de matéria mineral (&#1088;<0,05) e tendência decrescente para teores de energia bruta (&#1088;<0,05). Portanto, conclui-se que nas condições de realização deste trabalho, a inclusão de vitamina C no nível comercial foi suficiente para propiciar desempenho produtivo, benefícios para composição química nutricional e redução do estresse de manejo e despesca, igual para àquelas rações que receberam suplementação
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Caracterização química e avaliação de folhas de Talinum Patens Wand como complemento alimentar

Carvalho, Rosemary Duarte Sales January 2009 (has links)
104f. / Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2013-04-04T15:12:28Z No. of bitstreams: 3 PARTE3 em 23.11.2010.doc: 42496 bytes, checksum: 2d9616771769988e626bd84e402ff075 (MD5) PARTE1 em 23.11.2010.doc: 149504 bytes, checksum: 3420581741fc94ff7b966fbd699bd877 (MD5) PARTE 2 em 23.11.2010.doc: 5112320 bytes, checksum: c685fce455c694a320900678aa850b22 (MD5) / Rejected by Ana Hilda Fonseca(anahilda@ufba.br), reason: Pedir a aluna para transformar doc. em pdf e em um só arquivo on 2013-04-29T17:03:33Z (GMT) / Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2013-05-20T14:20:38Z No. of bitstreams: 1 Tese Rosemary.pdf: 1086365 bytes, checksum: def3bf1958e27ac363887006111d41c9 (MD5) / Approved for entry into archive by Ana Hilda Fonseca(anahilda@ufba.br) on 2013-05-20T14:23:44Z (GMT) No. of bitstreams: 1 Tese Rosemary.pdf: 1086365 bytes, checksum: def3bf1958e27ac363887006111d41c9 (MD5) / Made available in DSpace on 2013-05-20T14:23:44Z (GMT). No. of bitstreams: 1 Tese Rosemary.pdf: 1086365 bytes, checksum: def3bf1958e27ac363887006111d41c9 (MD5) Previous issue date: 2009 / CAPES / Os principais objetivos do presente trabalho foram determinar a composição mineral de folhas de Talinum patens Wand bem como conhecer o seu valor nutritivo e de substâncias bioativas através da determinação da composição centesimal, dos teores de vitamina C e de compostos fenólicos. No estudo da composição mineral os elementos determinados foram: bário, alumínio, zinco, cobre, ferro, manganês, níquel, cálcio, magnésio, fósforo, sódio e potássio. As amostras foram digeridas com mistura de ácido nítrico e peróxido de hidrogênio em sistema utilizando dispositivo de dedo frio. A técnica analítica para determinação dos conteúdos minerais empregada foi à espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). Considerando as 26 amostras analisadas, os resultados demonstraram que os elementos cálcio, magnésio, potássio, fósforo e sódio têm conteúdos médios e faixa de concentração, respectivamente de: 613 e 295 – 1089 mg 100g-1 para o cálcio; 915 e 510– 1447 mg 100g-1 para o magnésio; 398 e 204 – 525 mg 100g-1 para o potássio; 223 e 129 – 332 mg 100g-1 para o fósforo; 25 e 3 – 60 mg 100g-1 para o sódio. Os microelementos: alumínio, bário, zinco, cobre, ferro, manganês e níquel apresentaram media e faixa de: 7,4 e 0,52 – 23; 1,3 e 1,2 – 4,4; 4,4 e 1,2 – 11,90; 0,74 e 0,41 – 1,14; 7,5 e 4,0 – 12,0; 8,2 e 3,0 – 12,76; 0,15 e 0,09 – 0,55, mg 100g-1 respectivamente. Estes resultados indicam que “língua de vaca” pode ser utilizada na alimentação como fonte desses elementos. Para a determinação da composição centesimal em, g/100g, foram feitas as seguintes análises: proteínas, lipídios, umidade, carboidratos e valor calórico. Os resultados obtidos a partir das análises realizadas demonstraram que as folhas de “língua de vaca” apresentaram valor energético médio de 15,30 kcal e que o seu cozimento resulta em uma perda média de 40,8% do seu valor energético. Para a quantificação dos compostos fenólicos totais foi empregada a técnica de espectrofotometria molecular. Os valores obtidos de compostos fenólicos nas folhas secas em estufa e secas por liofilização foram de 51 a 87 e 61 a 164 mg g-1, respectivamente. Não foram observadas quantidades significativas de flavonoídes nas amostras analisadas. Para a determinação de vitamina C, foi empregado método titrimético, o teor médio encontrado nas amostras foi de 48 mg. 100g-1. Os resultados obtidos evidenciaram que as folhas de “língua de vaca” apresentaram valores nutritivos significativos. / Salvador

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