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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.
231

Pancreatic islet function in long-chain polyunsaturated [omega-3] fatty acid-depleted rats

Zhang, Ying January 2010 (has links)
Doctorat en Sciences médicales / info:eu-repo/semantics/nonPublished
232

ASSESSMENT OF OIL QUANTIFICATION METHODS IN SOYBEAN AND CHIA SEEDS AND CHARACTERIZATION OF OIL AND PROTEIN IN MUTANT CHIA (<em>SALVIA HISPANICA</em> L.) SEEDS

Al-Bakri, Ahmed N. 01 January 2017 (has links)
This thesis includes two main parts: I. Evaluation of techniques for oil (total lipid) quantification of chia and soybean seeds. This study evaluated ten different methods of seed oil quantification, including some methods that have not been applied to oilseeds before. The main aim of this study was to find one or more techniques that are easy, inexpensive, safe and fast with a small amount of ground seeds. The Soxhlet method was used as a standard to compared between techniques of oil quantification. The oil extraction by the Soxhlet method was evaluated with two solvents petroleum ether and acetone. There is not a statistically significant difference between petroleum ether and acetone solvents. No significant differences for the amount of oil recovered via the Soxhlet method were found between Medium Moisture Content (MMC > 10%) and Low Moisture Content (LMC < 4.0 %). The Folch technique provided higher percentages of oil extraction than Bligh and Dyer and hexane-isopropanol techniques. There is not a statistically significant difference (P =0.0844) between Soxhlet method and Folch method but less than the Soxhlet method. A supercritical fluid extraction (HCH) method provided a lower yield of oil extraction compared with the Soxhlet method for three varieties of bias samples. A Direct Transesterification (DT) method with LMC and MMC provided a statistically significant difference than the Soxhlet method. The DT with LMC produced higher yield than DT with MMC between samples but lower than the Soxhlet method. A Double Direct Transesterification (DDT) following Griffiths protocol provided more accurate results with the stir bar technique than sonication technique. 11 oilseeds bias samples (10 bias samples of soybean and one of chia) covering an oil content range of 15.4 to 32.6% showed, there is a significant difference between the Soxhlet and DDTG method and high oil quantification found with DDTG. A Double Direct Transesterification following Qiao et al. (2015) provided similar oil extraction to the Griffiths et al. (2010) method and also there is a significant difference between the Soxhlet and DDTQ method and higher oil recovered with DDTQ. The Bead Beating Extraction (BBE) protocol showed, there is a statistically significant difference ( P< 0.001) than the Soxhlet method. The BBE provided high oil quantification comparing with the Soxhlet method. The BBE provided the best results since it is the easiest, cheapest and fastest oil quantification method. A Nile red fluorescence technique yield no clear results. II. Characterization of oil and protein in mutant chia (Salvia hispanica L.) seeds. The objectives of this study were to (1) measure heritability in chia plants of levels of oil and protein content and seed yield and (2) Compare differences between two locations over two years for oil and protein percentages in chia and seeds yield. A population of 180 M3 mutant individual chia plants was harvested and for which forty M4 chia seeds were planted based on seed composition characteristics, with six plants representing each characteristic (high and lower oil, protein, and density and high yield). The forty M4 chia seeds were planted, with two replications for two locations, have been chosen in Kentucky one on Spindletop farm and the other in Quicksand farm. The M5 progeny seeds from plants grown in Spindletop and Quicksand contained significantly (P < 0.05) more protein than did seeds from the M4 parents. There were significant differences (P < 0.05) between locations where Quicksand obtain higher oil content than Spindletop. There was no significant difference between M5 parents seeds and M4 progeny seeds and higher yield kg/ha at Quicksand than Spindletop.
233

Uso de la torta residual de la semilla de sacha inchi (Plukenetia volubilis) como insumo alimenticio en la producción de conejos (Oryctolagus cuniculus) de carne y su enriquecimiento con omega - 3

Diaz Robles, Dianaliz Althair January 2016 (has links)
Enriquece la carne de conejo (Oryctolagus cuniculus) con ácidos grasos Omega-3 (ɷ-3) mediante el uso de la torta de semilla de Sacha Inchi (Plukenetia volubilis) como suplemento en su dieta. Se utilizaron 9 conejos hembras y 9 conejos machos de 70 días de edad y peso inicial promedio de 1415 g. Los conejos elegidos al azar fueron sometidos a tres tratamientos con tres repeticiones, considerando un conejo en cada jaula. Los tratamientos fueron: 1) T0: Dieta base + 0% de torta de semilla de Sacha Inchi (TSI); 2) T1: Dieta base + 2% de torta de semilla de Sacha Inchi; 3) T2: Dieta base + 4% de torta de semilla de Sacha Inchi. La ganancia de peso, consumo de alimento, conversión alimenticia fueron influenciados por los tratamientos dietéticos, de manera positiva sin diferencia estadística, entre tratamientos, mostrando un comportamiento satisfactorio con índices normales establecidos en la cunicultura, no obstruyeron la ventaja de la fijación del ω-3 en la carne. / Tesis
234

Use of Dietary Supplementation of Unsaturated Fatty Acids to Delay Onset of Learning and Memory Deficits in TgCRND8 Mice

Franko, Bettina January 2014 (has links)
Alzheimer’s disease (AD) is a complex neurodegenerative disorder, involving metabolic dysfunction, pathogenic aggregation of amyloid beta, and deteriorating cognitive function. Patients exhibit deficiency in omega-3,-6,-9 unsaturated fatty acids (UFAs) in plasma and brain membrane phospholipids, suggesting aberrant fatty acid metabolism influences pathology. Cognitive benefits of omega UFAs in AD remain unknown. Here, I examined effects of a four-month dietary supplementation with UFAs for capacity to alter learning and memory behaviour in an AD mouse model. Cognitive impairment in a fifth generation backcross (N5) C57BL/6Crl X C3H/HeJ TgCRND8 (Tg) mice was compared to control (NonTg) littermates, with respect to both males and females, at six months of age using the Morris Water Maze (MWM). Impairment differed between sexes; female Tg mice were severely impaired, whereas male Tg mice displayed delayed learning. A reduced visual acuity in Tg and NonTg mice, shown by adapted SLAG reflex test, did not impair spatial navigation in cued MWM. A four-month omega-6/-9 UFA oral treatment (75 mg/kg/day) improved learning and memory of Tg mice as compared to vehicle and untreated controls. Omega-3 UFAs, or vehicle alone, did not alter learning and memory of Tg and NonTg mice. Thus, dietary supplementation, particularly when enriched in omega-6/9 UFAs, can affect neural function, and delay conversion from a presymptomatic to symptomatic state in the TgCRND8 mouse model.
235

Ação antioxidante da vitamina E sobre a oxidação lipidica serica e hepatica de ratos wistar suplementados com acidos graxos poliinsaturados omega-3 / Antioxidant activity of vitamin E on the oxidation of serum lipids and liver Wistar rats supplemented with polyunsaturated fatty acids omega-3

Almeida, Flavia Queiroga Aranha de 06 February 2003 (has links)
Orientador : Admar Costa de Oliveira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-03T14:49:51Z (GMT). No. of bitstreams: 1 Almeida_FlaviaQueirogaAranhade_D.pdf: 8110954 bytes, checksum: f73d7dc068fcb0d734553e9c7d6917da (MD5) Previous issue date: 2003 / Resumo: O objetivo, deste trabalho, foi estudar o possível efeito protetor da vitamina E sobre a oxidação lipídica no sangue e no fígado de ratos Wistar, alimentados conforme dietas AIN93-G e suplementados por gavagem com ácidos graxos poliinsaturados ômega-3. Para o primeiro ensaio biológico, foram utilizados 60 ratos machos albinos, recém-desmamados, distribuídos aleatoriamente em 6 grupos experimentais, no qual foram divididos, de acordo com a quantidade de suplemento e marca, com e sem vitamina E: GRUPO 1 - Controle -Suplementação com 2 g/dia de óleo de soja; GRUPO 2 - Suplementação com 2 g/dia de ácidos graxos ômega-3 da marca A com vitamina E (120 mg/dia); GRUPO 3 - Suplementação com 2 g/dia de ácidos graxos ômega-3 da marca B, sem vitamina E; GRUPO 4 - Suplementação com 1 g/dia de ácidos graxos ômega-3 da marca A, com vitamina E (60 mg/dia); GRUPO 5 - Suplementação com 1 g/dia de ácidos graxos ômega-3 da marca B, sem vitamina E; GRUPO 6 - -Suplementação com 2 g/dia de ácidos graxos ômega-3 da marca B, sem vitamina E, por um período de 30 dias e, posteriormente, durante 15 dias, suplementação com vitamina E (marca C - 400 mg de acetato de DL-?--tocoferol). Nesse grupo, não houve sacrificio de animais no Tempo 1. Foram realizadas análises em três tempos: T0 - valor de referência após 3 dias em adaptação com dieta basal (sacrificados 12 animais, n=12); T1, com 30 dias de suplementação (sacrificados 4 animais por grupo, n=8), e T2, aos 45 dias de suplementação (sacrificados 4 animais por grupo, n=4). Para o segundo ensaio biológico, foram utilizados 80 ratos machos albinos, da linhagem Wistar, recém--desmamados. Inicialmente os 80 animais foram pesados e submetidos a um período de aclimatação ao ambiente, em gaiolas de crescimento individuais, durante 8 dias, em dieta não purificada de fórmula fechada Nuvital® para ganho de peso; em seguida, foram distribuídos aleatoriamente em quatro grupos experimentais, com 16 animais por grupo; os mesmos permaneceram por 4 dias em adaptação recebendo dieta basal e, ao final desse período, era feito o alinhamento do peso, retirando 4 animais por grupo, que foram sacrificados para análise lipídica do sangue e fígado; essa análise foi considerada "valor de referência" e denominada "Tempo 0". Permaneceram 64 animais (16 animais por grupo) dos quais, após 30 dias de experimento foram retirados 8 animais por grupo, para análise de sangue e fígado, denominado "Tempo 1", e, após 15 dias, foi feita mais uma análise, denominada "Tempo 2", nos animais restantes por grupo, para as avaliações dos perfis lipídicos sérico e hepático, dos lípides totais, ácidos graxos poliinsaturados ômega-3 e dosagem de vitamina E, como também a ação antioxidante da vitamina E. Os animais foram suplementados por gavagem, durante 45 dias consecutivos, por via oral. Os grupos experimentais, em estudo, foram divididos de acordo com a quantidade de suplemento com e sem vitamina E: GRUPO 1 - Controle - suplementação com 2 g/dia de óleo de soja; GRUPO 2 - Suplementação com 2 g/dia de ácidos graxos ômega-3 da marca A, com vitamina E (120 mg/dia); GRUPO 3 - Suplementação com 2 g/dia de ácidos graxos ômega-3 da marca B, sem vitamina E; GRUPO 4 - -Suplementação com 2 g/dia de ácidos graxos ômega-3 da marca B, sem vitamina E, por um período de 30 dias e posteriormente durante 15 dias, suplementação com vitamina E (marca C - 400 mg de acetato de DL-?- tocoferol). Nesse grupo, não houve sacrifício de animais no Tempo 1. No que diz respeito ao efeito antioxidante da vitamina E, nos teores de índice de peróxido (IP) e substâncias reativas ao ácido tiobarbitúrico (TBARS), observou- se que, nos grupos experimentais que receberam suplementação de AGPI ?-3 sem vitamina E, os teores de índice de peróxido e também os teores de substâncias reativas ao ácido tiobarbitúrico apresentaram valores muito superiores do que nos grupos experimentais que receberam suplementos de AGPI (?-3 com vitamina E. Assim, verificou-se que a vitamina E mostrou uma proteção efetiva contra a oxidação lipídica, em ratos Wistar, suplementados com produtos à base de ácidos graxos poliinsaturados (AGPI) ômega-3 (? - 3). Observou-se que não houve diferença significativa (p>0,05), nas médias no consumo de dieta (g) e do ganho de peso (g), entre os grupos em estudo, mostrando que as suplementações à base de ácidos graxos poliinsaturados ?-3, com e sem vitamina E, não interferiram nessas variáveis; que o tempo de suplementação com ácidos graxos poliinsaturados ômega-3 não foi capaz de melhorar o perfil lipídico sérico dos ratos, observando-se apenas uma redução dos teores de LDL-colesterol sérico dos ratos. A suplementação com ácidos graxos poliinsaturados ômega-3 não reduziu os teores hepáticos do colesterol total e triacilgliceróis dos ratos. Com relação à variação dos teores no sangue e no figado dos ácidos graxos saturados, monoinsaturados e poliinsaturados, observou-se que, ao longo da suplementação de 45 dias com AGPI ?-3, houve um aumento nos teores de ácidos graxos saturados palmítico, esteárico e dos insaturados, ácido oléico, ?-linolênico e DHA. A adição da vitamina E não interferiu nos teores encontrados. Tendo em vista os resultados encontrados, fica a recomendação de que, ao fazer uso de suplementação com ácidos graxos poliinsaturados ômega-3, sob forma concentrada em cápsulas gelatinosas, a mesma deve estar associada com vitamina E, para evitar os riscos de oxidação ao nível celular e, com isso, causar efeitos danosos a saúde / Abstract: The objective of this research was to study a possible protective effect of vitamin E against lipid oxidation in the blood and liver of Wistar rats fed on a AIN93-G diet supplemented by gavagem with polyunsaturated omega-3 fatty acids. For the first biological assay, 60 albino recent1y weaned male Wistar rats were used, distributed at random into 6 experimental groups. The experimental groups under study were divided according to the amount and brand of supplement, with and without vitamin E: GROUP 1 - Control - supplementation with 2 g/day soybean oil; GROUP 2 - supplementation with 2 g/day brand A omega-3 fatty acids with vitamin E (120 mg/day); GROUP 3 - supplementation with 2 g/day brand B omega-3 fatty acids without vitamin E; GROUP 4 -supplementation with 1 g/day brand A omega-3 fatty acids with vitamin E (60 mg/day); GROUP 5 - supplementation with 1 g/day brand B omega-3 fatty acids without vitamin E; GROUP 6 ¿ supplementation with 2 g/day brand B omega-3 fatty acids without vitamin E for a period of 30 days and subsequent1y for 15 days with vitamin E (brand C - 400 mg DL-?-tocopherol). In this group no animals were sacrificed at Time 1. In the second biological assay, 80 albino recently weaned male Wistar rats were used. Analyses were carried out at 3 points in time: TO - reference value after 3 days of adaptation on the basal diet (12 animals sacrificed, n=12); T1 after 30 days of supplementation (4 animals sacrificed per group, n=8) and T2 after 45 days of supplementation (4 animals sacrificed per group, n=4). The 80 animals were first weighed and submitted to an eight day period of acclimatization to the environment in individual growth cages, fed on a non-purified closed formula Nuvital® diet in order to gain weight. They were then distributed at random into four experimental groups, 16 animals per group, and fed for a further 4 days of adaptation on the basal diet before carrying out a weight alignment, when 4 animals per group were removed and sacrificed for a lipid analysis of their blood and liver. This analysis was considered as the "reference value" and denominated "Time O". Sixty-four animals thus remained (16 animals per group) of which, after 30 days of the experiment, 8 animals per group were removed for blood and liver analyses, denominated "Time 1", and after a further 15 days, another analysis, denominated "Time 2" was carried out on the remaining animals to evaluate the serum and hepatic lipid profiles, total lipids, omega-3 polyunsaturated fatty acids and the vitamin E content, as well as the anti-oxidant activity of the vitamin E. The animals were supplemented by gavagem for 45 consecutive days, via oral. The experimental groups under study were divided according to the amount and brand of supplement, with and without vitamin E: GROUP 1 - Control - supplementation with 2 g/day soybean oil; GROUP 2 - supplementation with 2 g/day brand A omega-3 fatty acids with vitamin E (120 mg/day); GROUP 3 -supplementation with 2 g/day brand B omega-3 fatty acids without vitamin E; GROUP 4 - supplementation with 2 g/day brand B omega-3 fatty acids without vitamin E; GROUP 5 - supplementation with 2 g/day brand B omega-3 fatty acids without vitamin E for a period of 30 days and subsequent1y for 15 days with vitamin E (brand C - 400 mg DL-?-tocopherol). In this group no animals were sacrificed at Time 1. With respect to the anti-oxidant effect of vitamin E on the peroxide index (PI) values and on the thiobarbituric acid reactive substances (TBARS), it was observed that in the experimental groups receiving ?-3 PUFA without vitamin E, the values for PI and for TBARS were much higher than for the experimental groups supplemented with ? -3 PUFA with vitamin E. Thus it was shown that vitamin E had a protective effect against lipid oxidation at the cellular level in Wistar rates supplemented with products based on ?-3 PUFA. No significant difference (p>0,05) was observed between the means for diet consumption (g) and weight gain (g), showing that supplementation with ?-3 PUFA, with and without vitamin E, did not interfere with these variables, and that the time of supplementation with ?-3 PUFA was not capable of improving the serum lipid profile of the rats, just a reduction in the levels of serum LDL-cholesterol being observed. Supplementation with ?-3 PUF A did not reduce the levels of total cholesterol or triglycerides in the rat livers. With respect to the variation of the levels of saturated, mono-unsaturated and poly-unsaturated fatty acids in the blood and liver, it was observed that during the 45 days of supplementation with ?-3 PUF A, there was an increase in the levels of the saturated fatty acids palmitic and stearic acids, oleic acid, ?-linolenic acid and DHA. The addition of vitamin E did not interfere with the values found. Considering the results obtained it can be recommended that, if using supplementation with ?-3 PUFA in a concentrated form in soft gels, it should be associated with vitamin E to avoid risks of oxidation at the cellular level, thus causing damage to the health / Doutorado / Doutor em Ciência de Alimentos
236

Reestructurados de pollo saludables, evaluación del efecto de varias estrategias tecnológicas combinadas

BOARI DE GREISSING, VIRGINIA MABEL 30 April 2014 (has links)
La innovación juega un rol clave en el desarrollo de nuevos productos y extensiones de línea. La reformulación de productos cárnicos es una estrategia, que aplica la industria actual, basada en el conocimiento de las necesidades y expectativas de los consumidores. Siguiendo estas tendencias se desarrolla un reestructurado de pollo con fibra soluble y omega 3, sin el agregado de grasa y sal. Para proteger los omega 3 de la autoxidación se emplean métodos de cocción a calor moderado y vacío en la precoccion del producto, que luego se va conservar en refrigeración. Además se evaluará la acción del nitrito en la estabilidad oxidativa, aunque se agrega por motivos de seguridad alimentaria. La fibra soluble se incorpora por aspectos tecnológicos como la retención de agua pero además por su reconocido efecto saluble. Y los omega tres vienen a paliar deficit nutricionales considerados críticos para la salud humana, en recientes avances de estudios de desnutrición. / Boari De Greissing, VM. (2014). Reestructurados de pollo saludables, evaluación del efecto de varias estrategias tecnológicas combinadas [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/37192 / TESIS
237

Produktion av fettsyror i mikrobiella system / Production of fatty acids in microbial systems

Radhakrishnan, Ganesh Kumar January 2014 (has links)
No description available.
238

Har kosttillskott med omega-3-fettsyror effekt vid autism? : En litteraturstudie om omega-3-fettsyrors effekt på hyperaktivitetssymtom hos autistiska barn.

Hasen, Yeldiz January 2022 (has links)
EPA and DHA are among the long-chain omega-3 fatty acids. Polyunsaturated fatty acids, including EPA and DHA, are fatty acids that are part of the diet and they are important structural molecules that include forming membrane membranes and. They are involved in the function of nerve cells and the brain. EPA and DHA are also necessary during early fetal development.  It can be difficult to get enough intake of EPA and DHA through diet alone. The daily recommendation for omega-3 fatty acids is 2.5-3 grams, but this amount is also include the omega-3 fatty acid, linolenic acid (ALA) which has a shorter carbon chain. It is an important component of our diet, as it is found in many common food plants but ALA does not provide the health benefits seen with EPA and DHA. The body can convert ALA from dietary sources to EPA and DHA via the enzymes enlongase and desaturase; however, enzyme capacity is low and research shows that only a small amount of DHA and EPA can be synthesized in the body. Therefore, dietary intake of EPA and DHA is important. In recent years, studies have shown that omega-3 fatty acids have health-promoting properties. This study summarizes the structural properties and dietary sources of omega-3 fatty acids and their effect on hyperactivity symptoms in children with ASD. The PubMed database was used to search for studies. Four published RCT studies were evaluated. The participants in the four studies were children between 2.5 and 8 years old. The effect of an average dose of 1,075 g of omega-3 fatty acids per day and its effects were investigated. Although the results of the four studies showed that the daily intake of omega-3 fatty acids reduced hyperactivity symptoms in children with autism, the results were not statistically significant. The conclusion is that although a decrease in hyperactivity was observed in children with ASD who received omega-3 fatty acids as a dietary supplement, there was not a statistically significant reduction in hyperactivity symptoms. More studies are needed to confirm whether treatment with omega-3 fatty acids reduces hyperactivity in children with ASD.
239

Inflammatory Pathways and Prevention Therapies in Placental Infection by Fusobacterium nucleatum

So, Jeewon January 2019 (has links)
Intrauterine infection with the oral commensal anaerobe Fusobacterium nucleatum has been associated with adverse pregnancy outcomes. We have previously established a mouse model to study the mechanism of hematogenous F. nucleatum leading to fetal and neonatal death. Here, we report that Toll-like Receptor 4 (TLR4) from the maternal rather than paternal, and endothelial rather than hematopoietic cells mediate placental inflammation, especially the production of the proinflammatory cytokine interleukin-1 beta. Downstream of TLR4, a spatiotemporal pattern of the transcription factor NF-kB activation was observed spreading from the decidual endothelium to the surrounding spongiotrophoblasts within the first six hours of infection. Maternal TRIF, an adaptor protein downstream of TLR4 pathway, but not NLRP3, a cytosolic signaling receptor that constitutes inflammasome complex, mediated the fetal and neonatal death. In an effort to find a prophylactic preventive method against the detrimental birth outcome induced by F. nucleatum placental infection, omega-3 fatty acids were tested for their anti-inflammatory properties. Omega-3 oil supplementation in pregnant mice inhibited the transcription and release of inflammatory cytokines, prevented fetal and neonatal death, and also suppressed the proliferation of F. nucleatum in the placenta. Moreover, omega-3 supplementation was shown to enhance neutrophil recruitment to the site of infection. However, omega-3 supplementation did not protect the pregnancy from Listeria monocytogenes infection in vivo, despite the in vitro results where inflammation induced by both Gram-negative and Gram-positive bacteria were suppressed by omega-3 fatty acids. This study presents the first direct evidence of maternal, rather than fetal, signal leading to adverse pregnancy outcome, and suggests an exciting therapeutic potential of dietary omega-3 fatty acids.
240

Neurodevelopmental Consequences of Maternal Omega-3 Fatty Acid Deficiency

Asch, Ruth H. 02 June 2020 (has links)
No description available.

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