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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.
61

The Effects of Flaxseed and Flaxseed Oil on the Gut-Brain Axis in Lipopolysaccharide-Challenged Male C57Bl/6 Mice

Livingston, Dawson 15 September 2022 (has links)
Individuals living with depression and anxiety show systemic increases of the bacterial endotoxin lipopolysaccharide (LPS), which induces an inflammatory cascade, resulting in negative effects across the gut-brain axis (GBA). LPS administration in mice has previously been used as a rodent model of depression/anxiety. Flaxseed (FS) contains key bioactives, including an omega-3 fatty-acid, dietary fibre, and a poly-phenolic compound which all may attenuate the effects of LPS through modulation of the GBA. The objectives of this thesis were to examine the effects of LPS on the GBA in C57Bl/6 mice and to determine if dietary supplementation with FS and/or FS oil (FO) provided protection against the LPS challenge. The LPS-induced negative effects across the GBA were partially attenuated by dietary supplementation with FS, but not FO, through changes in microbiota composition/function and systemic-/neuro-inflammation. Therefore, the potential benefits of FS are independent of the oil or are synergistic of all bioactives.
62

The Effect of Xanthan Gum and Guar Gum on Enhancing the Quality and Preventing Lipid Rancidity in Yeast Bread Supplemented with Flaxseed

Souther, Brandy Jolene 11 August 2005 (has links)
This study examined the effects of guar gum and xanthan gum on flax supplemented breads through objective and sensory testing. Breads containing flaxseed and gums were found to have a significantly (p<0.05) higher water activity than the control bread. Control bread was also found to have a higher (p<0.05) volume while flax breads containing guar gum had a significant (p<0.05) decrease in volume. Control bread and bread containing guar gum were significantly (p<0.05) harder in crumb texture. Breads with flax and xanthan gum displayed a significant (p<0.05) amount of springiness. While there was no significant (p>0.05) difference in peroxide values among bread samples, control bread had a lower (p<0.05) anisidine value indicating a decrease in hydroperoxide breakdown. While not significant (p>0.05), bread containing xanthan gum had a lower anisidine value than the other treatments. Sensory analysis found bread with both gums to be moister (p<0.05) and have a strong (p<0.05) yeasty aroma and fresher flavor. Control bread was found to have the least (p<0.05) yeasty aroma and taste significantly (p<0.05) less bitter but more stale. / Master of Science
63

FLAXSEED (Linum usitatissimum L.) GUM AND ITS DERIVATIVES: PHYSICOCHEMICAL PROPERTIES AND POTENTIAL INTERACTIONS WITH FOOD MACROMOLECULES

2016 April 1900 (has links)
Flaxseed (Linum usitatissimum L.) gum (FG) is a material with many potential food and non-food applications. Consistent performance is critical for FG utilization and this is possible through selection of genotype, characterization and optimization of constituents, and chemical modification. Physico-chemical and functional properties of FG aqueous solutions from six Canadian flaxseed cultivars were investigated. FG yield, carbohydrate composition, protein content, and zeta potential (ζ) varied among these cultivars. FG solution properties were also affected by temperature, solution pH, NaCl concentration, and sucrose concentration. Detailed studies were conducted on CDC Bethune FG (FGB) proteins that were separated by 2D-gel electrophoresis. Conlinin was identified as the major protein. Protease treatment decreased FGB solution emulsification properties suggesting that conlinin might enhance emulsification. Formation of BSA-FGB coacervates was monitored by turbidimetric analysis as a function of solution pH, biopolymer mixing ratio, NaCl and urea. Coacervates were stabilized primarily by attractive electrostatic forces and secondarily by hydrogen bonds. Further, anionic carboxymethyl ether moieties were introduced to FGB structure through ether forming reactions using monochloroacetic acid (MCA) to produce products with uniform properties. The highest degree of substitution (DS) was obtained at 70 °C, 7.0 M NaOH, and a molar ratio of MCA to FGB of 10:1 over 3 h. Carboxymethylated FGB (CMFG) exhibited both modified surface morphology and thermal behaviour. Solutions of CMFG demonstrated shear-thinning behaviour and apparent viscosity decreased with increased DS. A more liquid-like flow behaviour was observed for CMFG as DS increased. Findings here will introduce and expand FG applications in food or related fields with targeted performance.
64

The role of dietary fatty acids from plant-based oils in metabolic and vascular disease

Enns, Jennifer Emily January 1900 (has links)
Dietary fat has long been implicated in the etiology of metabolic and cardiovascular disease, and both the amount of fat and the fatty acid composition of the diet play a role in disease progression. Although national health organizations have set guidelines for the recommended intake of dietary fats, questions remain regarding the optimal dietary lipid profile for maintaining health and improving disease conditions. Whether certain types of fatty acids from plant-based oils can improve metabolic and vascular disease has been studied and debated, but not fully determined. In this study, we investigated the role of dietary fatty acids from plant-based oils, and examined their effects on metabolic and vascular disease parameters. Obese fa/fa Zucker rats were fed a diet containing flaxseed oil, which resulted in smaller adipocytes and decreased adipose tissue T-cell infiltration. Obese-prone Sprague Dawley rats were fed high-fat diets with different proportions of mono- and polyunsaturated fats. Changes were observed in adipose tissue levels of fatty acid synthase, adiponectin and fatty acid receptors GPR41 and GPR43, but other metabolic and inflammatory mediators in adipose tissue and serum remained stable. A systematic review and meta-analysis on the impact of n3 fatty acids on major cardiovascular endpoints showed that little evidence exists to support their role in peripheral arterial disease. Then again, very few studies on this topic have been conducted. To address this research gap, a clinical trial was designed to investigate the effects of a dietary intervention on blood vessel properties in people with peripheral arterial disease. Participants in the Canola-PAD Study consumed 25 g/day of canola oil or a Western diet oil mixture as part of their usual diet for 8 weeks. Although the intervention altered phospholipid fatty acids, vascular function, the lipid profile and inflammatory markers stayed relatively stable. Overall, this research demonstrates that dietary fatty acids from plant-based oils can be immunomodulatory, but at the physiological doses tested they are not potent mediators of functional changes in obesity or vascular physiology. / October 2015
65

Influência da relação 18:3n3/18:2n6 de rações exclusivamente vegetais sobre o metabolismo de ácidos graxos de juvenis de pacu (Piaractus mesopotamicus) / Influence of 18:3n3/18:2n6 ratio of exclusively vegetable diets on fatty acid metabolism of pacu (Piaractus mesopotamicus)

Segura, Julio Guerra 20 September 2016 (has links)
Novas alternativas de produção de ácidos graxos altamente insaturados n-3 (HUFA n-3) são procuradas mediante várias abordagens experimentais na área aquícola considerando que a oferta atual de óleos marinhos é limitada. Como os ácidos graxos das séries n-3 e n-6 são metabolizados mediante os mesmos processos enzimáticos, o aporte de ácidos graxos essenciais da dieta poderia influenciar nos níveis de alongamento e desaturação em função da disponibilidade relativa destes compostos. O objetivo deste trabalho foi determinar a influência de diferentes relações 18:3n3/18:2n6 (ALA/LA - ácido linolênico/ácido linoleico) de rações exclusivamente vegetais, sobre o metabolismo de ácidos graxos de juvenis de pacu (Piaractus mesopotamicus). Inicialmente 18 unidades experimentais (caixas com 16 peixes) foram alimentadas por 34 dias (C1) com uma dieta controle (tratamento T6) contendo óleo de tilápia como único ingrediente de origem animal. Posteriormente, foram formados aleatoriamente, 6 grupos com 3 unidades experimentais cada. Em uma segunda fase, durante 72 dias, 5 grupos receberam dietas, contendo óleo de linhaça e soja em substituição ao óleo de tilápia, com relações calculadas de ALA/LA de: 2,98 (T1); 1,68 (T2); 1,03 (T3); 0,61 (T4) e 0,35 (T5) e um grupo continuou com a dieta controle (T6). Nesta segunda fase, determinaram-se parâmetros de desempenho zootécnico e metabolismo de ácidos graxos em 3 intervalos de 24 dias (C2=58 dias, C3=82 dias e C4=106 dias). Os animais apresentaram crescimento e ganho de peso sem diferenças significativas entre os grupos e com aumento progressivo da proporção de gordura corporal total. A composição de ácidos graxos da dieta influenciou de forma proporcional sobre a composição da maioria de ácidos graxos de corpo inteiro. Os coeficientes de digestibilidade aparente aumentaram conforme o grau de instauração dos ácidos graxos e sua abundância relativa na dieta. A concentração de ácidos graxos polinsaturados nos lipídios de corpo inteiro não diferiu entre a maioria de tratamentos. O teor e aparecimento do ácido graxo 20:5n3 (EPA) e a atividade da enzima &Delta;-5 desaturase dos grupos T1, T2 e T3 foi menor que os demais tratamentos no período C4. O aparecimento de HUFA n-3 e n-6, atividade &Delta;-6 desaturase total e atividade &Delta;-6 desaturase sobre os ácidos graxos n-3 totais dos tratamentos T1 a T5 foram maiores que no T6 (controle). Estes resultados demonstram que o pacu (Piaractus mesopotamicus) é capaz de alongar e desaturar ácidos graxos essenciais para produzir ácidos graxos altamente insaturados (ácidos graxos com no mínimo 20 C e 3 ligações duplas - HUFA). Esta atividade é diminuída pela presença, mesmo em quantidades pequenas, de HUFA na dieta. Além disso, sugerem que relações ALA/LA da dieta, iguais ou maiores que 1, provocam diminuição na taxa de produção de 20:5n3, nos níveis testados neste estudo. / New alternatives for production of highly unsaturated fatty acids n-3 (n-3 HUFA) are sought by various experimental approaches in aquaculture, considering that the current supply of marine oils is limited. Since fatty acids of the n-3 and n-6 series are metabolized by the same enzyme processes, the supply of essential fatty acids of the diet could influence the elongation and desaturation levels, depending on the relative availability of these compounds. The objective of this study was to determine the influence of different 18:3n-3/18:2n-6 ratios (ALA/LA - linolenic acid/linoleic acid) of diets containing exclusively vegetable ingredients on the metabolism of fatty acids, of pacu juveniles (Piaractus mesopotamicus). Initially, 18 experimental units (boxes with 16 animals) were fed a control diet (T6 treatment) containing tilapia oil as the sole animal ingredient for 34 days (C1). Later, 6 groups with 3 experimental units each were formed at random. In a second phase, during 72 days, five groups were fed diets containing linseed and soy oils to replace tilapia oil, with calculated ALA/LA ratios: 2.98 (T1); 1.68 (T2); 1.03 (T3); 0.61 (T4) and 0.35 (T5) and a group continued with the control diet (T6). In the second phase were determined growth performance parameters and fatty acid metabolism in three intervals of 24 days (C2 = 58 days = 82 days and C3 C4 = 106 days). The animals showed growth and weight gain with no significant differences between groups and progressive increase in the proportion of total body fat. The fatty acid composition of the diet influenced proportionally on the composition of the majority of whole body fatty acids. The apparent digestibility increased as the degree of unsaturation of fatty acids and their relative abundance in the diet. The concentration of polyunsaturated fatty acids in whole body lipids did not differ among the most treatments. The content and appearance of the fatty acid 20:5n3 (EPA) and the activity of &Delta;-5 desaturase enzyme of groups T1, T2 and T3 was lower than the other treatments in C4 period. The appearance of n-3 and n-6 HUFA, &Delta; 6-desaturase activity and the total &Delta; 6-desaturase activity on the total n-3 fatty acids from T1 to T5 treatments were higher than T6 (control). These results demonstrate that pacu juveniles are able to elongate and desaturate essential fatty acids to produce highly unsaturated fatty acids. This activity diminishes by the presence of even small amounts of HUFAs in the diet. Moreover, it suggests that ALA/LA ratio of diet, equal to, or greater than one, cause a decrease in the rate of production of 20:5n3, within the levels tested in this study.
66

Sorvete a base de preparado em pó / Ice cream-based powder preparation

Lamounier, Marina Leopoldina 08 October 2012 (has links)
A obesidade é um problema sério de saúde pública e o consumo de alimentos com teores reduzidos de açúcar e gordura, associado à mudanças de hábitos alimentares e exercícios físicos vem de encontro ao desejo das pessoas que precisam perder peso. O presente trabalho teve como objetivo desenvolver diversas formulações de preparado lácteo funcional com diferentes teores de açúcar, gordura e inulina, além de quantidades préestabelecidas de linhaça e frutooligossacarídeo. Foram elaborados sorvetes de massa que além do preparado em pó, continham água e polpa de mangaba. Pode-se concluir que os preparados em pó e a fabricação dos sorvetes se apresentaram com forte potencial à comercialização, já que são ricos do ponto de vista nutricional e contemplam a demanda dos consumidores por produtos simultaneamente atrativos e saudáveis. / Obesity is a serious public health and the consumption of foods with reduced levels of sugar and fat, associated with changes in eating habits and exercise comes against the desire of people who need to lose weight. This study aimed to develop various functional dairy formulations prepared with different amounts of sugar, fat and inulin, and preestablished quantities of fructooligosaccharide and flaxseed. Were prepared ice cream mass than the powder form, containing water and mangaba. It can be concluded that the powder preparation and manufacture of ice cream that had a strong potential to marketing, since they are rich in nutritional point of view and contemplate the consumer demand for products simultaneously attractive and healthy.
67

Utilização de óleo de peixe e linhaça na ração como fontes de ácidos graxos poliinsaturados ômega-3 em ovos de galinha / Dietary fish oil and flaxseed as sources of omega-3 polyunsaturated fatty acids in chicken eggs

Mori, Agnes Veridiana 13 December 2001 (has links)
Foram utilizadas 288 galinhas poedeiras Babcock, durante o periodo de 9 semanas, com o objetivo de se verificar o efeito de teores crescentes de linhaça, associados ou não ao óleo de peixe na ração, sobre o perfil de ácidos graxos do ovo. Paralelamente, avaliou-se o desempenho das aves, qualidade externa e interna, características sensoriais e teor de colesterol dos ovos. Foi empregado esquema fatorial 2X6 em blocos casualizados, sendo as aves alimentadas com dieta controle (isenta de produtos de origem animal) contendo linhaça moída (0%, 7%, 14%,21%, 28% e 35%), adicionada ou não de óleo de peixe (2%). O peso dos ovos sofreu redução significativa (p<0,05) a partir do uso de 21% de linhaça na ração, e de 14% quando da associação com o óleo de peixe. A postura das aves foi reduzida com a utilização de 28% e 35% de linhaça na ração, independentemente do uso de óleo de peixe na dieta. A qualidade dos ovos não foi alterada com o uso de ambos ingredientes e o teor de colesterol, expresso em mg/g, foi significativamente aumentado com 35% de linhaça. O teor de ácido linolênico na gema sofreu aumento crescente com a elevação da concentração dietética de linhaça, sendo sua deposição acentuada com a adição concomitante de óleo de peixe. A porcentagem de EPA (ácido eicosapentaenóico) na gema foi significativamente elevada com a utilização de 35% de linhaça na ração, sendo que o uso combinado de óleo de peixe determinou incremento do EPA a partir de 7% de linhaça na dieta. A concentração de DHA (ácido docosahexaenóico) na gema foi significativamente aumentada a partir de 7% de linhaça dietética, sendo este incremento mais marcante com a associação do óleo de peixe. O óleo de peixe e a linhaça na ração determinaram relação ômega-6/ômega-3 (n-6/n-3) estreita na gema, de acordo com recomendações nutricionais vigentes. As equações de regressão permitem estimar os teores de ácido Iinolênico, EPA, DHA, ácido araquidônico, total de ácidos graxos poliinsaturados (PUFAs) n-3 e relação n-6/n-3 na gema a partir de concentrações de linhaça e de ácido linolênico na ração. O sabor de peixe foi detectado nos ovos provenientes dos grupos alimentados com óleo de peixe combinado com 28 e 35% de linhaça. Para se maximizar os teores de PUFAs n-3, especialmente os de cadeia longa, sem resultar em prejuízo do desempenho produtivo e do sabor dos ovos, a combinação de 2% de óleo de peixe com 7% de linhaça na ração mostrou ser a mais adequada. / To investigate the effect of increasing levels of dietary flaxseed, combined or not with fish oil, upon fatty acid composition of eggs, 288 Babcock laying hens were used for a 9 week experimental period. Reproductive performance of hens, internal and external egg quality, egg flavor, and yolk cholesterol levels were evaluated. The experiment had a 2X6 factorial design, hens were fed a basal diet (without animal products) supplemented with ground flaxseed (0%, 7%, 14%,21%,28% and 35%), combined or not with fish oil (2%). Egg weight was significantly decreased (p<0,05) frem 21% dietary flaxseed, and from 14% when fish oil was added to the diet. In birds fed either 28% or 35% flaxseed, egg production was depressed, regardless of the addition of fish oil. Feeding diets containing both fat sources did not affect egg quality, and yolk cholesterol content (mg/g) was significantly increased in eggs laid by hens fed 35% flaxseed. Yolk concentrations of linolenic acid were enhanced as a result of feeding hens increasing levels of dietary flaxseed, and its deposition was markedly increased when fish oil was included in the diet. Yolk contents of EPA (eicosapentaenoic acid) were significantly increased when diets included 35% flaxseed, and the combination with fish oil produced enhanced levels of EPA from 7% dietary flaxseed. Egg contents of DHA (docosahexaenoic acid) were significantly increased from 7% dietary flaxseed, and the deposition of such n-3 fatty acid was greater when in combination with fish oil. Dietary fish oil and flaxseed caused a narrow ratio of n-6 to n-3 fatty acids, meeting the current dietary allowances. Regression equations allow to predict contents of linolenic acid, EPA, DHA, arachidonic acid, total of n-3 fatty acids and ratio of n-6 to n-3 in the yolk from levels of dietary flaxseed or linolenic acid. Fishy flavor was detected in eggs from hens fed 2% fish oil combined with flaxseed at 28 or 35%. In order to maximize the content of n-3, mainly the longer chain n-3 fatty acids, without impairing performance parameters and egg flavor, the combination of 2% fish oil and 7% flaxseed in the hen\'s diet is the most appropriate.
68

Efeito das sementes de Linum usitatissimum L. var. humile (Mill.) Pers. (linhaça marrom) no aparelho reprodutor de ratas ovariectomizadas / Effect of Linum usitatissimum L. var. Humile (Mill.) Pers. (Brown flax) in the reproductive system of ovariectomized rats

Gonçalves, Elaine Mendes 30 April 2014 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-06-14T18:11:39Z No. of bitstreams: 1 ElaineGoncalves.pdf: 1963435 bytes, checksum: 82486914fc2c74cc35d67f82ca6caa16 (MD5) / Made available in DSpace on 2017-06-14T18:11:39Z (GMT). No. of bitstreams: 1 ElaineGoncalves.pdf: 1963435 bytes, checksum: 82486914fc2c74cc35d67f82ca6caa16 (MD5) Previous issue date: 2014-04-30 / Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão (FAPEMA) / The hormone replacement therapy is the most effective way for the treatment of conditions related to post-menopause, but is related to the presence of undesirable effects. In this situation, safer alternatives have been investigated for the treatment of menopausal symptoms arising, such as the use of phytoestrogens. Seeds of Linum usitatissimum L. (flaxseed) are rich in lignan precursor, which is converted to substances which are structurally similar to estrogen. This study evaluates the effect of the hydro alcoholic extract of the seeds of L. usitatissimum on the reproductive tract of ovariectomized female Wistar rats. The seeds were crushed and remacerated and three times in 70% ethanol in the ratio 1:3 (v/v) for 24 hours to obtain the extract. Adult rats (80 days) from Rattus norvegicus species, divided into 6 groups (n = 5-6) were used: sham operated (FO) and ovariectomized (OVR) administered distilled water/3% cremophor (0.1 ml/100g, v. o.); estradiol benzoate (BE), ovariectomized treated with estradiol benzoate at a dose of 10 μg/kg (s. c.) and three ovariectomized groups treated with the extract of L. usitatissimum at doses of 100 mg/kg (LIN100), 250 mg/kg (LIN250) or 500 mg/kg (LIN500). The rats were ovariectomized and 21 days after surgery, received daily treatments, for two months, when it was rated the estrous cycle, body weight and food consumption. At the end of this period, blood was collection and subsequent biochemical and hormonal analyzes, and organ weighing, uterine reactivity and uterus, vagina and breasts histology. In the analysis of the estrous cycle, the OVR group had a higher frequency in the diestrus stage during the 2 months. The LIN100 group showed up 100% in diestrus and LIN250, 94.5% (1st month) and 93.5% (2nd month). At the highest dose tested (LIN500 group), flaxseed showed in the 2nd month of treatment, 14.3% of pro-estrus and diestrus 61.9%. The BE group reached 100% of estrus in the 2nd month. Ovariectomy induced body weight gain in OVR group (19.6%) which was prevented in the groups LIN and BE. Moreover, the groups treated with the extract did not alter uterus weight in relation to OVR, which showed a decrease of 83.4% compared to the FO. However, in BE, were increased by 80.5% the uterus weight. Ovariectomy induced intra-abdominal fat gain which was reduced to 47.9% in the LIN500 group 35.5% and 45.8% in BE group. In biochemical analyzes no differences between the groups was observed. In hormone dosage, OVR group decreased by 75.3% in estradiol compared to FO, whereas in the groups treated with the extract showed no differences compared to OVR. In relation to progesterone, there was no difference between groups. Uterine responsiveness to carbachol, PGF2α and oxytocin was decreased with ovariectomy and L. usitatissimum extract did not alter this effect. Histomorphometric analysis of the uterus, LIN500 group showed a significant increase in the luminal epithelium of the uterus in 12.8%, when compared to the OVR group. The other parameters did not differ, as well as the breasts histomorphometry. Therefore, the hydro alcoholic extract of L. usitatissimum has potential as an alternative to therapy in postmenopausal women, as it showed cytological parameters and on adipose tissue effects, without stimulating breast and endometrial tissues. / A terapia de reposição hormonal é forma mais eficaz para o tratamento de sinais e sintomas da pós-menopausa, entretanto está relacionada à presença de efeitos indesejáveis. Por esse motivo, tem-se buscado alternativas mais seguras para o controle destes sintomas, como o uso de fitoestrógenos. As sementes de Linum usitatissimum L. (linhaça) são ricas em um precursor de lignana, que é convertido no intestino em substâncias que se assemelham estruturalmente ao estrogênio. Este trabalho objetivou avaliar o efeito do extrato hidroalcoólico das sementes de L. usitatissimum no aparelho reprodutor de ratas Wistar ovariectomizadas. As sementes foram turbolizadas e remaceradas três vezes em etanol 70% na proporção 1:3 (v/v), por 24 horas, para a obtenção do extrato. Foram utilizadas ratas adultas (80 dias) da espécie Rattus norvegicus, distribuídos em 6 grupos (n=5-6): grupo falso operado (FO) e grupo ovariectomizado (OVR), administrados com água destilada/cremofor a 3% (0,1 mL/ 100g, v.o.); grupo benzoato de estradiol (BE), ovariectomizado tratado com estradiol na dose de 10 μg /kg (s.c.) e outros três grupos ovariectomizados tratados, por via oral, com o extrato de L. usitatissimum nas doses de 100 mg/kg (LIN100), 250 mg/kg (LIN250) ou 500 mg/kg (LIN500). As ratas foram ovariectomizadas e, após 21 dias da cirurgia, receberam diariamente os tratamentos, por 2 meses, período que foi avaliado ciclo estral, peso corporal e consumo alimentar. Ao final do tratamento, o sangue foi coletado para análises bioquímica e hormonal, além da pesagem de órgãos, reatividade uterina e histologia do útero, vagina e mamas. Na análise do ciclo estral, o grupo OVR permaneceu com maior frequência na fase diestro durante os 2 meses. O grupo LIN100 apresentou-se 100% em diestro e o LIN250, 94,5% (1º mês) e 93,5% (2º mês). Na maior dose testada (grupo LIN500), a linhaça mostrou, no 2º mês, 14,3% de pró-estro e 61,9% de diestro. O grupo BE atingiu 100% de estro no fim do tratamento. A ovariectomia induziu aumento de peso corporal no grupo OVR (19,6%), que foi prevenido nos grupos LIN e BE. Além disso, os grupos tratados com o extrato não alteraram o peso uterino em relação ao OVR, que mostrou uma redução de 83,4% em comparação ao FO. Porém, no BE, houve aumento de 80,5% do peso uterino. A ovariectomia induziu um aumento na gordura intra-abdominal em 47,9% que foi reduzida no grupo LIN500 em 35,5% e no grupo BE em 45,8%. Nas análises bioquímicas não foi observada diferenças entre os grupos. Já na dosagem hormonal, o grupo OVR mostrou redução de 75,3% do estradiol em relação ao FO, enquanto que nos grupos tratados com o extrato não houve diferença em relação ao OVR. Para a progesterona, não houve diferença entre os grupos. A reatividade uterina ao carbacol, prostaglandina F2α e ocitocina foi diminuída com a ovariectomia, porém não foi alterada com o extrato de L. usitatissimum. Na análise histomorfométrica do útero, o grupo LIN500 mostrou um discreto aumento do epitélio luminal uterino em 12,8%, quando comparado ao grupo OVR. Para os outros parâmetros não houve diferenças, assim como na histomorfometria das mamas. Portanto, o extrato hidroalcoólico de L. usitatissimum apresenta potencial como alternativa à terapêutica na pós-menopausa, pois mostrou efeitos em parâmetros citológicos e tecido adiposo, sem estimular tecidos mamário e endometrial.
69

Avaliação dos efeitos antioxidantes e anti-genotóxicos in vivo da semente de linum usitatissimum l.

Zuravski, Luísa 24 May 2013 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-04-08T19:07:36Z No. of bitstreams: 1 Luísa Zuravski.pdf: 1510633 bytes, checksum: a6f936910f8580e5397f9e32aefb5643 (MD5) / Made available in DSpace on 2016-04-08T19:07:36Z (GMT). No. of bitstreams: 1 Luísa Zuravski.pdf: 1510633 bytes, checksum: a6f936910f8580e5397f9e32aefb5643 (MD5) Previous issue date: 2013-05-24 / As plantas são consideradas a melhor fonte de antioxidantes naturais. Entre elas, um alimento funcional largamente utilizado é a linhaça (Linum usitatissimum L.). A linhaça é composta basicamente por minerais, vitaminas, proteínas e lipídeos. Adicionalmente, contêm quantidades significativas de outros componentes bioativos como polifenóis, ácidos graxos poliinsaturados, fibras e lignanas. Relata-se que uma refeição contendo linhaça tem um elevado potencial nutricional, não somente pelo teor de proteínas, mas também pela quantidade de fibras solúveis e lignanas. O uso popular está em plena ascensão, entretanto, ainda existem poucos trabalhos envolvendo humanos. Assim, o objetivo deste estudo foi avaliar a variedade (linhaça marrom ou dourada), forma de apresentação mais eficaz (farinha de linhaça ou grãos) e os reais benefícios da linhaça sob o status oxidativo, nível glicêmico e perfil lipídico em voluntários humanos saudáveis. Para isso, 48 voluntários foram selecionados e orientados a ingerirem 40g diárias de linhaça in natura pela manhã, durante 14 dias. Coleta de sangue venoso em jejum, medidas antropométricas e de pressão arterial foram realizadas antes e após o período de suplementação. Os resultados demonstraram que os parâmetros clínicos não modificaram significativamente no período de 14 dias de suplementação, mas mudanças significativas nos marcadores de estresse oxidativo foram observadas. Observou-se um efeito significativo da intervenção dietética com grãos de linhaça dourada ou marrom em proteger as proteínas plasmáticas e os lipídeos de membrana da ação danosa das espécies reativas. Este efeito positivo não foi observado na suplementação com farinha de linhaça marrom ou dourada. Esta ausência de resultado pode estar relacionada com o conteúdo de flavonoides que se apresenta maior no grão e mostra uma notável capacidade de neutralizar espécies reativas. A concentração de polifenóis plasmáticos diminuiu significativamente após 14 dias de suplementação. Este resultado, possivelmente, é consequência direta da neutralização de espécies reativas geradas pela metabolização dos ácidos graxos linoleico e linolênico, presentes na linhaça. Os teores de vitamina C aumentaram após 14 dias de ingestão de linhaça marrom ou dourada, mostrando a presença desta vitamina na semente. Os dados não mostraram nenhuma alteração na análise de danos ao DNA pelo teste cometa e frequência de micronúcleos. A defesa antioxidante enzimática, Superoxido dismutase, Catalase e Glutationa peroxidase, não mostraram alterações significativas em suas atividades após o período de suplementação. Assim, os resultados indicam que a semente de linhaça, na forma de grão, em ambas as variedades, pode ser um valioso suplemento, auxiliar no tratamento de doenças que apresentam como base os radicais livres. / Plants are considered the best source of natural antioxidants. Among them, a functional food widely used is flaxseed (Linum usitatissimum L.). Flaxseed is composed mainly of minerals, vitamins, proteins and lipids. Additionally, contain significant amounts of bioactive compounds such as polyphenols, polyunsaturated fatty acids, fibers and lignans. It is reported that a meal containing flaxseed has a high nutritional potential, not only for protein content, but also by the amount of soluble fiber and lignans. The popular use is on the rise, however, there are few studies involving humans. The objective of this study was to evaluate the variety (brown or golden flaxseed), presentation more effective (flax flour or grains) and the real benefits of flaxseed on oxidative status, glucose level and lipid profile in healthy human volunteers. For this, 48 volunteers were selected and instructed to ingest 40g of flaxseed daily fresh in the morning for 14 days. Venous blood was collected in fasting, anthropometric and blood pressure measurements were performed before and after the supplementation period. The results demonstrate that clinical parameters did not change significantly within 14 days of supplementation, but significant changes in markers of oxidative stress were observed. There was a significant effect of dietary intervention with grain flaxseed golden or brown in protecting plasma proteins and membrane lipids of harmful action of reactive species. This positive effect was not observed in supplementation with flour flaxseed golden or brown. This lack of result may be related to the content of flavonoids which shows a remarkable ability to neutralize reactive species. The plasma concentration of polyphenols significantly decreased after 14 days of supplementation. This result is possibly a direct consequence of the neutralization of reactive species generated by metabolism of linoleic and linolenic fatty acids present in flaxseed. The vitamin C increased after 14 days of taking flaxseed golden or brown, showing the presence of this vitamin in the seed. The data showed no change in the analysis of DNA damage by comet assay and micronucleus frequency. The antioxidant defense enzymes, superoxide dismutase, catalase and glutathione peroxidase, showed no significant changes in their activities after the supplementation period. Thus, the results indicate that the flaxseed in the form of grain in both varieties can be a valuable supplement assist in treatment of diseases that have as base free radicals.
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Encapsulation of flaxseed oil within modified lentil protein isolate matrices

2013 March 1900 (has links)
The overarching goal of this research was to formulate an encapsulated powder using a modified lentil protein isolate-maltodextrin mixture to encapsulate flaxseed oil by freeze drying. The primary objectives were: a) to examine the physicochemical and emulsifying properties of lentil protein isolates with different degrees of hydrolysis; b) to design and test the physicochemical properties of encapsulated flaxseed oil using a wall material with native, heat treated and partially hydrolyzed lentil proteins in combination with maltodextrin; and c) test the oxidative stability of encapsulated flaxseed oil with the capsule design with the lowest surface oil and highest encapsulation efficiency versus free oil. During the first study, the physicochemical and emulsifying properties of lentil protein isolates (LPI) were investigated as a function of their degree of hydrolysis (DH of 4, 9 and 20%) following exposure to trypsin/heat. Interfacial tension, surface characteristics (charge and hydrophobicity) and intrinsic fluorescence were determined and related to changes in the emulsification activity (EAI) and stability indices (ESI) of unhydrolyzed (u-LPI) and hydrolyzed LPI (h-LPI) in a flaxseed oil-water emulsion. Most importantly surface hydrophobicity declined from ~30 to ~24 for the u-LPI and h-LPI (DH 4-20%), respectively. The changes in physicochemical properties induced by hydrolysis had a detrimental effect on EAI and ESI values, which declined from ~51 to ~47 m2 g-1 and ~12 to ~ 11 min for u-LPI and h-LPI (DH 4-20%), respectively. In the second study, the physicochemical properties of encapsulated flaxseed oil within lentil protein-based maltodextrin microcapsules were investigated using native (n-LPI), pre-treated (heated, un-hydrolyzed (u-LPI); and heated, hydrolyzed (h-LPI)) lentil protein isolates and as a function of oil load (10.0, 20.0 and 30.0% of total solids). The moisture, water activity, surface oil and encapsulation efficiency (EE) were assessed, along with droplet size and emulsion morphology. Light microscopy imaging of the emulsions, showed that the h-LPI had slightly larger oil droplets than the n-LPI and u-LPI, which both appeared similar. Microcapsules prepared from h-LPI showed significantly higher surface oil and lower EE than both the n-LPI and u-LPI materials. The microcapsules prepared using n-LPI with 10.0% oil loading were found to have the lowest surface oil content (~3.7%) and highest EE (~62.8%) for all formulations, and were subjected to an oxidative storage stability test over a 30 d period vs. free oil. The encapsulation process however induced autooxidation leading the production of a greater amount of primary oxidative products than free oil. Findings indicate that future studies are necessary to enhance the stability of the flaxseed oil through the encapsulation process.

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