Thesis (MScAgric)--Stellenbosch University, 2008. / ENGLISH ABSTRACT: Different substances were evaluated and compared to an antibiotic, in terms of their effect on nitrogen - and amino acid digestibilities. Two digestibility trials and one performance trial were conducted. Trials one and two apparent nitrogen (AND)- and amino acid (AAD) digestibilities were determined from digesta collected at the terminal ileum (ileal digestibility method). In Trial 3 the substances were evaluated in terms of their potential to improve production performance. Broilers were fed a maizesoya based diet throughout the three trails. In the first trial, garlic and a commercial prebiotic (Bio-Mos®), were tested and compared in terms of AND and AAD, to an antibiotic (doxycyclin, Doxyvete-SOS). A starter and finisher diet were fed as either mash or pellets. The garlic was included at 8g/kg, 13g/kg and 18g/kg to the starter and finisher diets. Bio-Mos® was added at 1g/kg, 2g/kg and 3g/kg to the starter diet, and 0.5g/kg, 1g/kg and 1.5g/kg to the finisher diet. The doxycyclin was added at 0.3 g/kg. None of the treatments had any beneficial effects in terms of AND. Feeding a pellet seem to have some negative effects in terms of AND. In general most of the treatments did not show any improvement in AAD at any determination period (day 21, 28 or 35). At day 21 and day 35, the mash diet supplemented with 18g/kg garlic had a negative effect on AAD, when compared to the negative and positive control. It doesn’t seem that feeding either a mash or a pellet had an influence on the effects exerted by the different treatments. In the second trial the influence of Bio-Mos®, a blend of organic acids, probiotics and electrolytes (Acid-Pak 4-way®) and a medium-chain triglyceride (MCT) were evaluated and compared in terms of AAD and AND, to the effect of an antibiotic, doxycyclin. The starter and finisher diets were fed as a mash. Bio-Mos® was included at 1g/kg, 2g/kg, and 3g/kg in the starter diet, and at 0.5g/kg, 1g/kg, 1.5g/kg in the finisher diet, respectively. Acid-Pak 4-way® was included at 0.4g/kg, 1g/kg and 1.6g/kg for both the starter and finisher diets. Medium-chain triglycerides (MCT) were allocated at 3g/kg, 3.6g/kg, 4.2g/kg for the starter diet, and 2.1g/kg, 2.7g/kg and 3.4g/kg for the finisher diet. An antibiotic, doxycyclin, was included at 0.3 g/kg. With AND, no treatment had any significant effect for the entire experimental period. At day 21, the treatment supplemented with MCT (3.4g/kg) had the most significant beneficial effect on AAD, when compared to the negative- and positive controls, as it increased AAD for the majority of the amino acids. The treatment with Acid-Pak 4-way® (1g/kg) had the most significant negative effect on AAD when compared to the positive control. At day 28, the treatments with Bio-Mos® (0.5g/kg and 1.5g/kg) and Acid-Pak 4-way® (0.4g/kg) had the most significant beneficial effect on AAD when compared to the positive control. It increased AAD for more than half of the 17 amino acids evaluated. The treatment supplemented with MCT (2.7g/kg) has shown the most significant negative effect on AAD, when compared to the positive control. In the third trial the effect of Bio-Mos®, Acid-Pak 4-way® and MCT on production performance was evaluated, and compared to the effects of the presence or absence of doxycyclin. Body weight (BW), body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) were measured. The starter and finisher diets were fed as a mash. Bio-Mos®, MCT and Acid-Pak 4-way® were included at 3.0g/kg, 4.2g/kg and 1.6g/kg, respectively in the starter and finisher diets. Birds were weighed (per pen) on arrival and on days 7, 14, 21, 28, 35. Feed intake (FI) per pen was measured at days 7, 14, 21, 28 and 35, and mortality was recorded daily. In terms of BWG, Acid-Pak 4-way® had a higher BWG, when compared to the negative control, Bio-Mos® and MCT. It can be concluded that Bio-Mos®, Acid-Pak 4-way®, as well as MCT can be a possible alternatives to antibiotic supplementation. These three treatments did not necessary prove to be more effective than antibiotics, but are definitely competitive alternatives. / AFRIKAANSE OPSOMMING: Verskillende behandelings is geëvalueer en vergelyk met ‘n antimikrobiese produk, in terme van hul uitwerking op stikstof - en aminosuur verteerbaarhede. Twee verteringstudies en produksieprestasie studie is uitgevoer. In die eerste twee studies is die skynbare stikstof (AND)- en aminosuur (AAD) verteringskoöeffisiënte bepaal deur gebruik te maak van digesta wat by die terminale ileum ingesamel is (ileale verteringsmetode). In die derde studie is die produksie prestasie van braaikuikens op ‘n gebalanseerde metaboliseerbare energie (AME) rantsoen, soos beïnvloed deur die verskillende behandelings, geëvalueer. In die eerste studie is knoffel en ‘n kommersiële prebiotikum (Bio-Mos®) geëvalueer en met ‘n antibiotikum (doksisiklien, Doxyveto-SOS) in terme van AND en AAD vergelyk. Beginner- en afrondingsrantsoene is as ‘n meel of pille gevoer. Die knoffel is teen 8g/kg, 13g/kg en 18g/kg in die rantsoen ingesluit. Bio-Mos® is teen 1g/kg, 2g/kg en 3g/kg in die beginner rantsoen en teen 0.5g/kg, 1g/kg en 1.5g/kg in die afrondingsrantsoen, ingesluit. Die antibiotikum is teen 0.3g/kg in beide rantsoene ingesluit. Geen van die behandelings het enige positiewe invloed op AND gehad nie. Deur ‘n verpilde rantsoen te voer het sekere negatiewe invloed op AND gehad. Oor die algemeen het geen behandelings enige positiewe invloed op AAD gehad nie. Op dag 21 en 35 het die insluiting van knoffel teen 18g/kg in ’n meel rantsoen ’n negatiewe invloed op AAD gehad, wanneer dit met die negatiewe- en positiewe kontroles vergelyk is. Dit blyk nie dat om ‘n pil of meel te voer enige invloed op die invloede van die verskillende behandelings gehad het nie. In die tweede studie is Bio-Mos®, ‘n organiese suur (Acid-Pak 4-way®) en ‘n medium-ketting trigliseried (MCT) geëvalueer en met ‘n antbiotikum, doksisiklien (Doxyveto-SOS) in terme van AND en AAD, vergelyk. Beginner- en afrondingsrantsoene is gevoer as ‘n meel. Bio-Mos® is teen 1g/kg, 2g/kg, and 3g/kg in die beginner rantsoen en teen 0.5g/kg, 1g/kg, 1.5g/kg in die afrondingsrantsoen, ingesluit. Acid-Pak 4-way® is teen 0.4g/kg, 1g/kg en 1.6g/kg vir die beginner –en afrondingsrantsoene ingesluit. Die MCT is teen 3g/kg, 3.6g/kg, 4.2g/kg in die beginner rantsoen en teen 2.1g/kg, 2.7g/kg en 3.4g/kg in die afrondingsrantsoen ingesluit. Die antibiotikum is ingesluit teen 0.3g/kg. Geen behandelings het enige betekenisvolle invloed in terme van AND gehad nie. Op dag 21 het MCT (3.4g/kg), in vergelyking met die negatiewe- en positiewe kontrole, die grootste positiewe invloed op AAD gehad. Acid-Pak 4-way® (1g/kg) het, in vergelyking met die positiewe kontrole, ‘n positiewe invloed gehad op AAD. Op dag 28, het Bio-Mos® (0.5g/kg en 1.5g/kg) en Acid-Pak 4-way® (0.4g/kg) die grootste positiewe invloed op AAD gehad. Die behandeling met MCT (2.7g/kg) het die mees negatiewe invloed op AAD gehad. In die derde studie is die insluiting van Bio-Mos®, Acid-Pak 4-way® en MCT getoets om die invloed op braaikuiken produksie prestasie te evalueer, en te vergelyk met die invloed van die insluiting of afwesigheid van ‘n antibiotikum. Liggaamsmassa (BW), liggaamsmassa toename (BWG), voerinname (FI) en voeromsetverhouding (FCR) is gemeet. Beginner- en afrondings rantsoene is gevoer as ‘n meel. Bio-Mos®, MCT en Acid-Pak 4-way® is onderskeidelik teen 3.0g/kg, 4,2g/kg en 1.6g/kg in die rantsoen ingesluit. Die kuikens is met aankoms (per hok) geweeg, asook op dae 7, 14, 21, 28, 35. Voerinname per hok is gemeet op dae 7, 14, 21, 28 en 35. Mortaliteite is daagliks aangeteken. Die insluiting van Acid-Pak 4-way® het in vergelyking met die negatiewe kontrole, Bio-Mos® en MCT insluiting ‘n hoër BWG tot gevolg gehad. Die gevolgtrekking wat gemaak kan word is dat Bio-Mos®, Acid-Pak 4-way® en MCT gebruik kan word as ‘n moontlike alternatief vir antibiotika insluiting. Hierdie drie behandelings was nie noodwending meer effektief as die antibiotika nie, maar het wel bewys dat dit kompeterende alternatiewe is.

Através da mistura de óleos e gorduras e de posterior interesterificação, é possível obter compostos denominados de lipídios estruturados. Estes compostos formados pelo rearranjo de triacilgliceróis de cadeias médias e longas apresentam características físicas, químicas e nutricionais diferentes dos lipídios que lhes deram origem. Devido a sua potencial capacidade para a prevenção e tratamento de doenças, também podem ser considerados "nutracêuticos" por apresentarem vantagens clínicas que se encontram associadas aos ácidos graxos de cadeia média (AGCM) e à estrutura particular de sua molécula lipídica formada pela interesterificação. Esta pesquisa empregou dois métodos de modificação de óleos e gorduras: mistura e interesterificação. As matérias-primas utilizadas foram gorduras refinadas de palma e de palmiste, e triacilgliceróis de cadeia média (Trigliceril CM). Foi utilizado um planejamento de dez experimentos. Para as respostas analíticas foi aplicado um modelo de regressão múltipla, do tipo cúbico especial. Os resultados foram apresentados em diagramas triangulares. Estabeleceu-se ainda a correlação entre medidas quantitativas de aspectos morfológicos microscópicos com as características físicas das gorduras. Foram realizadas análises dos pontos de amolecimento e fusão, viscosidade, consistência, conteúdo de gordura sólida, distribuição estereoespecífica dos ácidos graxos através de hidrólise enzimática, e estrutura cristalina das amostras antes e após a reação de interesterificação química. A análise dos resultados indicou que as interações ocorridas entre os três componentes não foram significativas para os pontos de amolecimento e fusão, para a viscosidade e para a consistência antes da interesterificação, e, para o conteúdo de gordura sólida antes e após a interesterificação. Os coeficientes negativos para os parâmetros analisados demonstraram a existência de um efeito antagônico, próprio de interações eutéticas entre misturas de gorduras. Os pontos de amolecimento e de fusão foram dependentes das gorduras de palma e palmiste e das interações ocorridas entre os triacilgliceróis de cadeia média (TCM) e as gorduras de palma e palmiste. A viscosidade dependeu das gorduras de palma, palmiste e TCM. A consistência dependeu das gorduras de palma e palmiste e das interações binárias entre TCM e palmiste e entre palma e palmiste. O conteúdo de gordura sólida dependeu das gorduras de palma e palmiste e das interações binárias entre elas. Estabeleceram-se, ainda, diagramas triangulares, onde foram indicadas curvas de níveis. Os resultados da distribuição estereoespecífica demonstraram que, antes do rearranjo ao acaso, houve preferência do ácido oléico pela posição sn-2, enquanto que os ácidos palmítico e esteárico distribuíram-se principalmente pelas posições sn-1 e sn-3. Nos lipídios estruturados, os ácidos graxos saturados aumentaram sua participação na posição central do triacilglicerol, enquanto os ácidos graxos insaturados apresentaram diminuição nesta mesma posição. Para a estrutura cristalina foram determinados a dimensão fractal, o diâmetro e o número dos cristais, às temperaturas de 15, 20, 25 e 30ºC. Os números de cristais estiveram compreendidos entre 38 a 5245 e entre 33 a 3318, antes e depois da interesterificação, respectivamente. A dimensão fractal variou de 1,47 a 2,44 e de 1,35 a 2,59, antes e após a interesterificação, respectivamente. Os diâmetros médios dos cristais antes da interesterificação estiveram na faixa de 11,93 a 643,48m e, após a interesterificação, os valores variaram de 12,96 a 299,20m. Os lipídios estruturados apresentaram menor número de cristais e menores dimensões fractais que as misturas originais, com exceção da amostra que continha 2/3 de gordura de palma. / Structured lipids are compounds that can be synthesized by blending followed interesterification of fats and oils. These compounds, formed by rearrangement of medium and long chain tryacylglicerols show physical, chemical and nutritional characteristics different from the original lipids. They can also be considered “nutraceuticals” because of their potentiality in preventing and treating illnesses. This is due to the present clinical advantages associated to the medium chain fatty acids (MCFA) and also, the particular structure of the lipidic molecule formed by the interesterification. Two lipid modification methods were used in this study: blending and interesterification. Refined palm oil, palm kernel oil and medium chain tryacylglicerols (Trigliceril CM) were used as raw material. Ten experiments were planned and carried out. A mathematical model using the special cubic type multiple regression was applied to the analytical responses obtained. The results were shown in triangular diagrams where the contour curves were traced. A correlation between the quantitative measures of the microscopic morphologic aspects and the physical characteristics of the lipids was also established. The following analysis were carried out: determination of softening and melting points, viscosity, consistency, solid fat content, stereospecific distribution of fatty acids by enzymatic hydrolysis technique, and crystal structure of samples obtained before and after chemical interesterification. The results show that the interactions that occurred amongst the three components were not significant in relation to the softening and melting points, the viscosity, and the consistency before interesterification, and the solid fat content before and after interesterification. The negative coefficients of the parameters analyzed show an antagonic effect, which is characteristic of eutectic interactions amongst fats. The softening and melting points depended on the palm and palm kernel fats, and on the interactions that occurred between the medium chain tryacylglicerols (MCT) and the palm and palm kernel fats. The viscosity depended on the palm and palm kernel fats and on the medium chain tryacylglicerols (MCT). The solid fat content depended on the palm and palm kernel fats and on the binary interactions between them. The results of the stereospecific distribution showed that, instead of a random distribution, oleic acid was preferably esterified at the sn-2 position, whereas palmitic and stearic acids were mainly distributed at the sn-1 and sn-3 positions. The saturated fatty acids in the structured lipids increased their participation in the tryacylglicerol central position, whereas the unsaturated fatty acids decreased their participation at the same position. Fractal dimension, crystal diameter, and crystal number at 15, 20, 25 and 30ºC were determined to analyze the crystal structure. Fractal dimension varied from 1,47 to 2,44 and from 1,35 to 2,59 before and after the interesterification reaction, respectively. The crystal number varied from 38 to 5245 and from 33 to 3318, before and after the interesterification reaction, respectively. The average diameter of the crystals before interesterification varied from 11,93 to 643,48m and, after interesterification, these values varied from 12,96 to 299,20m. Structured lipids showed a smaller crystal number and smaller fractal dimensions than the original mixtures, with exception of the sample containing 2/3 of palm oil.

Através da mistura de óleos e gorduras e de posterior interesterificação, é possível obter compostos denominados de lipídios estruturados. Estes compostos formados pelo rearranjo de triacilgliceróis de cadeias médias e longas apresentam características físicas, químicas e nutricionais diferentes dos lipídios que lhes deram origem. Devido a sua potencial capacidade para a prevenção e tratamento de doenças, também podem ser considerados "nutracêuticos" por apresentarem vantagens clínicas que se encontram associadas aos ácidos graxos de cadeia média (AGCM) e à estrutura particular de sua molécula lipídica formada pela interesterificação. Esta pesquisa empregou dois métodos de modificação de óleos e gorduras: mistura e interesterificação. As matérias-primas utilizadas foram gorduras refinadas de palma e de palmiste, e triacilgliceróis de cadeia média (Trigliceril CM). Foi utilizado um planejamento de dez experimentos. Para as respostas analíticas foi aplicado um modelo de regressão múltipla, do tipo cúbico especial. Os resultados foram apresentados em diagramas triangulares. Estabeleceu-se ainda a correlação entre medidas quantitativas de aspectos morfológicos microscópicos com as características físicas das gorduras. Foram realizadas análises dos pontos de amolecimento e fusão, viscosidade, consistência, conteúdo de gordura sólida, distribuição estereoespecífica dos ácidos graxos através de hidrólise enzimática, e estrutura cristalina das amostras antes e após a reação de interesterificação química. A análise dos resultados indicou que as interações ocorridas entre os três componentes não foram significativas para os pontos de amolecimento e fusão, para a viscosidade e para a consistência antes da interesterificação, e, para o conteúdo de gordura sólida antes e após a interesterificação. Os coeficientes negativos para os parâmetros analisados demonstraram a existência de um efeito antagônico, próprio de interações eutéticas entre misturas de gorduras. Os pontos de amolecimento e de fusão foram dependentes das gorduras de palma e palmiste e das interações ocorridas entre os triacilgliceróis de cadeia média (TCM) e as gorduras de palma e palmiste. A viscosidade dependeu das gorduras de palma, palmiste e TCM. A consistência dependeu das gorduras de palma e palmiste e das interações binárias entre TCM e palmiste e entre palma e palmiste. O conteúdo de gordura sólida dependeu das gorduras de palma e palmiste e das interações binárias entre elas. Estabeleceram-se, ainda, diagramas triangulares, onde foram indicadas curvas de níveis. Os resultados da distribuição estereoespecífica demonstraram que, antes do rearranjo ao acaso, houve preferência do ácido oléico pela posição sn-2, enquanto que os ácidos palmítico e esteárico distribuíram-se principalmente pelas posições sn-1 e sn-3. Nos lipídios estruturados, os ácidos graxos saturados aumentaram sua participação na posição central do triacilglicerol, enquanto os ácidos graxos insaturados apresentaram diminuição nesta mesma posição. Para a estrutura cristalina foram determinados a dimensão fractal, o diâmetro e o número dos cristais, às temperaturas de 15, 20, 25 e 30ºC. Os números de cristais estiveram compreendidos entre 38 a 5245 e entre 33 a 3318, antes e depois da interesterificação, respectivamente. A dimensão fractal variou de 1,47 a 2,44 e de 1,35 a 2,59, antes e após a interesterificação, respectivamente. Os diâmetros médios dos cristais antes da interesterificação estiveram na faixa de 11,93 a 643,48m e, após a interesterificação, os valores variaram de 12,96 a 299,20m. Os lipídios estruturados apresentaram menor número de cristais e menores dimensões fractais que as misturas originais, com exceção da amostra que continha 2/3 de gordura de palma. / Structured lipids are compounds that can be synthesized by blending followed interesterification of fats and oils. These compounds, formed by rearrangement of medium and long chain tryacylglicerols show physical, chemical and nutritional characteristics different from the original lipids. They can also be considered “nutraceuticals" because of their potentiality in preventing and treating illnesses. This is due to the present clinical advantages associated to the medium chain fatty acids (MCFA) and also, the particular structure of the lipidic molecule formed by the interesterification. Two lipid modification methods were used in this study: blending and interesterification. Refined palm oil, palm kernel oil and medium chain tryacylglicerols (Trigliceril CM) were used as raw material. Ten experiments were planned and carried out. A mathematical model using the special cubic type multiple regression was applied to the analytical responses obtained. The results were shown in triangular diagrams where the contour curves were traced. A correlation between the quantitative measures of the microscopic morphologic aspects and the physical characteristics of the lipids was also established. The following analysis were carried out: determination of softening and melting points, viscosity, consistency, solid fat content, stereospecific distribution of fatty acids by enzymatic hydrolysis technique, and crystal structure of samples obtained before and after chemical interesterification. The results show that the interactions that occurred amongst the three components were not significant in relation to the softening and melting points, the viscosity, and the consistency before interesterification, and the solid fat content before and after interesterification. The negative coefficients of the parameters analyzed show an antagonic effect, which is characteristic of eutectic interactions amongst fats. The softening and melting points depended on the palm and palm kernel fats, and on the interactions that occurred between the medium chain tryacylglicerols (MCT) and the palm and palm kernel fats. The viscosity depended on the palm and palm kernel fats and on the medium chain tryacylglicerols (MCT). The solid fat content depended on the palm and palm kernel fats and on the binary interactions between them. The results of the stereospecific distribution showed that, instead of a random distribution, oleic acid was preferably esterified at the sn-2 position, whereas palmitic and stearic acids were mainly distributed at the sn-1 and sn-3 positions. The saturated fatty acids in the structured lipids increased their participation in the tryacylglicerol central position, whereas the unsaturated fatty acids decreased their participation at the same position. Fractal dimension, crystal diameter, and crystal number at 15, 20, 25 and 30ºC were determined to analyze the crystal structure. Fractal dimension varied from 1,47 to 2,44 and from 1,35 to 2,59 before and after the interesterification reaction, respectively. The crystal number varied from 38 to 5245 and from 33 to 3318, before and after the interesterification reaction, respectively. The average diameter of the crystals before interesterification varied from 11,93 to 643,48m and, after interesterification, these values varied from 12,96 to 299,20m. Structured lipids showed a smaller crystal number and smaller fractal dimensions than the original mixtures, with exception of the sample containing 2/3 of palm oil.

Cardiovascular disease (CVD) represents the principal cause of mortality in this country and the prevalence is increasing amongst the lower socioeconomic classes. Modifiable risk factors, that can be removed or controlled by means of changes of lifestyle, are distinguished amongst the variables related to this occurence. Of these factors, tobacco smoking, sedentary behavior and bad eating habits, are significant. The diet, in this case, can exert a protecting or promoting influence on CVD. Amongst the dietary factors, saturated fat has important deleterious effects on the health of the heart. However,even though they belong to the same category of lipids, some triglycerides present metabolic behavior differentiated by virtue of their structural characteristics, particularly the size of the hydrocarbon chain. Thus, it is possible that medium chain triglycerides (MCT) do not represent a cardiovascular risk factor and, on the contrary, can even exert a protective effect. The coconut is a product widespread in the northeast of Brazil, and its oil, rich in MCT, is widely used in the food industry, however it has been poorly accepted for use in the domestic diet, possibly in view of the belief that, without scientific foundation, it is a possible hypercholesterolemic agent. The objective of this study was to ascertain the effect of the consumption of coconut oil on the cardiovascular risk factors and body composition of obese women. This dissertation consists of two articles, one being a literature study and the other presenting the results of an investigation conducted on a sample of 40 women (aged 20 to 40) that were overweight (25 < BMI > 35 kg/m2) and with a waist circumference (WC) > 88cm, randomly allocated into 2 groups, for the consumption of soya oil (S) or coconut oil (C). Anthropometric and biochemical evaluations were performed before (T1) and after 12 weeks (T2) of the lipid supplements. The groups consumed 30ml of oil daily, respectively of soya or coconut, divided amongst the three principal meals. The results demonstrated that the groups presented similar BMI in T1 (31.1 ± 3.3 vs 31.0 ± 3.6). In T2 it had been significantly reduced intra-group but not inter-group (30.7 ± 3.4 vs 30.5 ± 3.6). There was a significant reduction in WC in group C (98.8 ± 6.7 vs 97.4 ± 7.0; p = 0.004) but not in group S (97.1 ± 6.1vs 97.4 ± 5.35; p = 0.48). There was a reduction in the level of HDL in group S. All the other biochemical parameters remained unaltered in all the groups (glycemia, HOMA S, HOMA % &#946;, insulin, triglycerides, total cholesterol, fibrinogen). Therefore it was concluded that the daily consumption of 30g of coconut oil, in this population for a period of 3 months, did not cause dyslipidemia and promoted a reduction in WC. / As doenças cardiovasculares (DCV) representam a principal causa de mortalidade em nosso país e vem apresentando aumento de prevalência nas classes de menor nível socioeconômico. Entre as variáveis relacionadas à sua ocorrência, destacam-se os chamados fatores de risco modificáveis, os quais podem ser removidos ou controlados mediante mudanças no estilo de vida. Entre esses fatores destacam-se o tabagismo, o sedentarismo e os maus hábitos alimentares. A dieta, dessa forma, pode exercer um papel de proteção ou promoção das DCV, sendo a gordura saturada, dentre os fatores dietéticos, um importante agente deletério à saúde do coração. Todavia, mesmo pertencendo a esta categoria de lipídios, alguns triglicerídeos apresentam comportamento metabólico diferenciado em virtude de suas características estruturais, especialmente, o tamanho da cadeia hidrocarbonada. Assim, é possível que os triglicerídeos de cadeia média (TCM) não representem um fator de risco cardiovascular e, ao contrário, possam até exercer um efeito protetor. O coco é um produto bastante difundido no Nordeste brasileiro e seu óleo, rico em TCM, é amplamente utilizado pelas indústrias alimentícias, porém pouco aceito para uso dietético domiciliar, possivelmente em virtude da crença, sem fundamentação científica, de ser um possível agente hipercolesterolêmico. Desta forma objetivou-se verificar o efeito do consumo de óleo de coco sobre os fatores de risco cardiovascular e composição corporal de mulheres obesas. Esta dissertação aborda essa temática por meio de dois artigos, sendo um deles de revisão da literatura e o outro apresentando os resultados de uma investigação conduzida em uma amostra de 40 mulheres (20 a 40 anos) portadoras de sobrepeso (25< IMC < 35 Kg/m2) e circunferência da cintura (CC) > 88cm, aleatoriamente alocadas em 2 grupos, segundo o consumo de óleo de soja (S) ou óleo de coco (C). Procederam-se avaliações antropométricas e bioquímicas antes (T1) e após 12 semanas (T2) de suplementação lipídica. Os grupos consumiam diariamente 30 ml de óleo, respectivamente, de soja ou de coco, racionados nas três principais refeições. Os resultados demonstraram que os grupos apresentaram IMC semelhantes em T1 (31,1 ± 3,3 vs. 31,0 ± 3,6). Em T2 houve redução significativa intragrupo mas não inter grupo (30,7 ± 3,4 vs. 30,5 ± 3,6). Houve redução significativa na CC no grupo C (98,8 ± 6,7 vs. 97,4±7,0; p=0,004) mas não no grupo S (97,1 ± 6,9 e 96,3 ± 5,35; p=0,48). Houve redução do nível de HDL no grupo S. Todos os demais parâmetros bioquímicos permaneceram inalterados em ambos os grupos (glicemia, HOMA S, HOMA % &#946;, insulina, triglicerídeos, colesterol total, fibrinogênio). Desta forma concluiu-se que o consumo diário de 30 g de óleo de coco nesta população por um período de 3 meses não causou dislipidemia e promoveu redução na CC.

The main importance of temporal lobe epilepsy due to its high prevalence and high proportion of patients with refractory epilepsy to treatment, making it necessary in this case, the use of alternative therapies, such as the ketogenic diet. This diet is rich in fat, low in carbohydrates and proteins, and since 1921 has been used for patients unresponsive to medical therapy. This dissertation deals with the investigation of the effects of the ketogenic diet based on triheptanoin in epileptic seizures in rats and was developed in the form of two articles. The first article, The role of the ketogenic diet on oxidative stress occurring in epilepsy, presents a review of the relationship between oxidative stress and epilepsy, highlighting the possible beneficial effect of ketogenic diet in this context. Several results show that, in fact, this dietary method reduces oxidative stress markers. The second article, entitled Effects of ketogenic diet based on triheptanoin in seizures of rats with epilepsy induced by pilocarpine, describes the experimental study conducted in Wistar rats were divided into three groups, named according to the diet received, in control (standard diet AIN-93G), CetoTAGC7 (ketogenic based in triheptanoin; AIN-93G diet modified to contain 4% soybean oil, 25.79% of triheptanoin and 40% margarine) and CetoTAGsoja (ketogenic based in soybean; AIN-93G diet modified to contain 29.79% of soybean oil margarine and 40%). The ratio lipid: carbohydrate + protein ketogenic diets was 3.5:1 (control diet, 1:11,8) and experimental period lasted 19 days. It was found that the energy value of the share of feed intake and weight gain made by the three groups during the experimental period were not different (P> 0.05). There was no significant difference among the three groups regarding the ratio of feed efficiency (P> 0.05). The behavioral analysis showed no difference for the variable frequency of spontaneous recurrent seizures, however the duration of the attacks of animals belonging to the group triheptanoin was lower in the last experimental day. Future additional research are encouraged, therefore, the results of this study indicate, however modestly, to a potential beneficial effect of triheptanoin to control seizures, which could be investigated under different conditions, like a period longer than is tested by this protocol. / A principal importância da epilepsia do lobo temporal decorre de sua alta prevalência e elevada proporção de pacientes com crises epilépticas refratárias ao tratamento medicamentoso, fazendo-se necessário, neste caso, o uso de terapias alternativas, como a dieta cetogênica. Esta dieta é rica em lipídeos, pobre em carboidratos e proteínas e desde 1921 tem sido utilizada para pacientes não responsivos à terapia medicamentosa. A presente dissertação trata da investigação dos efeitos da dieta cetogênica à base de trienantina nos episódios convulsivos de ratos epilépticos e foi desenvolvida na forma de dois artigos. O primeiro artigo, O papel da dieta cetogênica no estresse oxidativo presente na epilepsia, apresenta uma revisão sobre a relação existente entre o estresse oxidativo e a epilepsia, destacando o possível efeito benéfico da dieta cetogênica neste contexto. Vários resultados atestam que, de fato, esta modalidade dietética diminui os marcadores de estresse oxidativo.O segundo artigo, intitulado Efeitos da dieta cetogênica à base de trienantina nos episódios convulsivos de ratos portadores de epilepsia induzida por pilocarpina, descreve o estudo experimental, realizado em ratos Wistar, subdivididos em três grupos, denominados, segundo a dieta recebida, em Controle (dieta padrão AIN-93G), CetoTAGC7 (cetogênico à base de trienantina; AIN-93G modificada para conter 4% de óleo de soja, 25,79% de trienantina e 40% de margarina) e CetoTAGsoja (cetogênico à base de soja; AIN-93G modificada para conter 29,79% de óleo de soja e 40% de margarina). A proporção lipídeos:carboidratos+proteína das dietas cetogênicas foi de 3,5:1 (dieta controle, 1:11,8) e o período experimental totalizou 19 dias. Verificou-se que o valor energético da cota de ração ingerida e o ganho de peso apresentado pelos três grupos, no período experimental, não foram diferentes (P>0,05). Não houve diferença significativa entre os três grupos, quanto ao coeficiente de eficiência alimentar (P>0,05). As análises comportamentais demonstraram que não houve diferença para a variável frequência de crises recorrentes espontâneas, entretanto a duração das crises dos animais pertencentes ao grupo da trienantina foi menor no último dia experimental. Pesquisas adicionais futuras são encorajadas, pois, os resultados do presente estudo apontam, ainda que modestamente, para um potencial efeito benéfico da trienantina no controle de crises epilépticas, que poderia ser investigado em condições diferentes, a exemplo de um período de tempo superior ao testado pelo presente protocolo de pesquisa.

Les acides gras saturés à chaîne moyenne (AGCM) ont été décrits comme potentiellement bénéfiques pour réguler la balance énergétique chez l’homme. Cependant, la récente découverte de l’activation de la ghréline, hormone gastrique orexigène, par l’acide octanoïque (C8:0), ajoute un nouveau niveau de complexité dans la compréhension des effets physiologiques des AGCM. En effet, pour être reconnue par son récepteur hypophysaire, la ghréline doit préalablement être octanoylée par la Ghréline O-Acyltransférase (GOAT). Or, les paramètres régulés par la ghréline ainsi modifiée s’opposent aux effets connus des AGCM, en favorisant la prise alimentaire et la prise de masse. L’élaboration d’inhibiteurs de la GOAT constitue donc une stratégie thérapeutique nouvelle pour lutter contre l’obésité. Les AGCM sont essentiellement apportés par l’alimentation,leur biosynthèse endogène n’ayant été décrite que dans les cellules de la glande mammaire en lactation. Etudier l’impact du C8:0 d’origine alimentaire sur l’octanoylation de la ghréline est donc d’autant plus pertinent, car celui-ci est suspecté de fournir à la GOAT le co-substrat nécessaire à l’octanoylation. Afin de mieux comprendre l’apparente contradiction entre les effets connus des AGCM sur la masse corporelle et la satiété, et l’effet de l’octanoylation de la ghréline, quatre approches ont été mises en œuvre: (1) Etude des effets physiologiques du C8:0 à différentes doses sur l’axe ghréline-GOAT et sur le métabolisme chez le rat adulte, (2) Etude de l’absorption gastrique du C8:0 par inhibition de la lipase préduodénale, chez le / Medium chain fatty acids (MCFA) have been described as potentially beneficial for regulating human energetic balance. However, the recent discovery of the orexigenic ghrelin activation by octanoic acid revealed a new level of complexity in MCFA effects. Ghrelin must be octanoylated by the Ghrelin O-Acyltransferase (GOAT) to bind its pituitary receptor. Interestingly, the effects mediated by the post-translationally modified ghrelin seem opposed to MCFA known effects, increasing food intake and body weight. Development of GOAT inhibitors could then constitute a therapeutic strategy against obesity. MCFA are mainly provided by the diet, as their endogenous synthesis has only been described in lactating mammary glands. Dietary caprylic acid is then suspected to provide the GOAT enzyme with octanoyl- CoA co-substrates necessaryfor the acyl modification of ghrelin. My objective is to understand the discrepancy between the formerly described beneficial effects of dietary MCFAs on body weight loss and the C8:0 newly reported effect on appetite stimulation via ghrelin octanoylation. This thesis is divided into four parts: (1) Study of C8:0 physiological effects on ghrelin-GOAT axis, in rat, (2) Study of C8:0 gastric absorption by inhibition of preduodenal lipase, in young rat, (3) Study of C8:0 metabolism in gastric cells in vitro, (4) Preliminary study of GOAT activity in vitro.

Dietary intervention remains a popular, albeit challenging, approach for combating obesity. In recent years, dietary interventions that increase consumption of medium-chain triglycerides (MCT) instead of long-chain triglycerides (LCT) have gained attention. Pre-clinical research has demonstrated that rats fed a high-fat diet (HFD) induce adiposity, but a dietary shift from LCT to MCT suppresses this effect. To date, the extent to which this effect operates via suppressed hyperphagia is not fully understood. In the present study, we sought to determine how consuming a HFD composed of different fat types affects energy intake, adiposity, and hippocampal brain-derived neurotropic factor (BDNF) levels. Rats were assigned to one of four diet groups – rat chow (CHOW), LCT-enriched HFD (LCT-HFD), MCT-enriched HFD (MCT-HFD), or coconut oil-enriched HFD (COCO-HFD), which composes a mixture of LCT and MCT. In Experiment 1, all animals were given <i>ad libitum</i> access to their assigned diet, whereas in Experiments 2 and 3, HFD-subjects were pair-fed to CHOW to prohibit hyperphagia. In Experiments 1 and 2, subjects were aged 20-24 weeks, whereas in Experiment 3, subjects were aged 10-11 weeks. Across experiments, we found that the effect of MCT consumption on suppressing HFD-induced adiposity is causally related to suppressed HFD-induced hyperphagia. Additionally, we failed to detect an effect of HFD consumption on hippocampal BDNF. Therefore, our findings did not support or oppose the hypothesis that MCT consumption attenuates HFD-induced BDNF deficiency. Future studies should focus on determining the causal relationship between MCT consumption, energy expenditure, and HFD-induced adiposity.

No description available.

Introdução: A doença hepática gordurosa não alcoólica é caracterizada pelo acúmulo hepático de lipídeos, principalmente na forma de triglicerídeos. Devido à atividade inflamatória progressiva pode evoluir para uma forma mais grave, a esteatohepatite não alcoólica. Os ácidos graxos poli-insaturados ômega-3 são associados a efeitos metabólicos positivos para redução da esteatose hepática, no entanto, são mais susceptíveis a peroxidação lipídica. Os triglicerídeos de cadeia média (TCMs) promovem a prevenção do bloqueio da beta-oxidação de ácidos graxos e redução da peroxidação lipídica, no entanto os efeitos na redução da esteatose ainda são controversos. Objetivo: O objetivo do estudo foi avaliar as implicações da dieta hiperlipídica (HL+) com óleo de peixe ou com óleo de TCM no desenvolvimento da esteatose hepática, no perfil de ácidos graxos hepáticos e no estresse oxidativo em ratos. Metodologia: Cinquenta ratos machos da linhagem wistar foram divididos em 5 grupos. Os animais receberam água e comida a vontade durante 45 dias. A adaptação a dieta HL+ foi realizada nos primeiros 15 dias. A composição da dieta do grupo que recebeu somente a gordura animal (HL+GA) era de 50% de gordura animal, e a dieta dos grupos HL+OS, HL+TCM e HL+OP era composta por 35% de gordura animal e 15% de óleo de soja, óleo de TCM e óleo de peixe, respectivamente. Resultados: Todos os grupos que receberam as dietas hiperlipídicas apresentaram maior acúmulo de gordura total e de triglicerídes hepaticos e somente os grupos HL+GA e HL+TCM apresentaram maior acúmulo de colesterol total hepático em relação ao controle. O grupo HL+TCM apresentou maior acúmulo percentual de gordura e um exacerbado acúmulo de triglicerídeos hepáticos em relação aos grupos alimentados com as dietas HL+. A redução do colesterol total sérico foi observada nos grupos HL+TCM e HL+OP, comparados ao controle. A maior incorporação hepática dos ácidos graxos EPA e DHA no grupo HL+OP contribuiu para o aumento do Índice de Peroxibilidade dos ácidos graxos e das substâncias reativas ao ácido tiobarbitúrico livres e totais e para a depleção da vitamina E no fígado. A maior razão AGS/AGPI hepática observada no grupo HL+TCM contribuiu para a preservação dos antioxidantes hepáticos. A alanina aminotransferase, um marcador de dano hepático, apresentou-se aumentada em todos os grupos que receberam as dietas HL+. Conclusões: A dieta hiperlipídica foi eficiente na indução do acúmulo de gordura hepática. O uso do óleo de TCM foi associado a uma maior concentração de lipídeos e preservação dos antioxidantes hepáticos. A dieta hiperlipídica com óleo de peixe foi associada ao aumento significativo na peroxidação lipídica, apesar do menor acúmulo de colesterol e triglicerídeos hepaticos. / Introduction: The Non-alcoholic Fatty liver disease is characterized by hepatic accumulation of lipids, mainly in the form of triglycerides. The disease may progress to a more severe form, the Non-alcoholic steatohepatitis, due to progressive inflammatory activity. Many authors have shown positive metabolic effects associated with the use of polyunsaturated omega-3 fatty acids and reduction in hepatic steatosis. However, these fatty acids are more susceptible to lipid peroxidation. The medium chain triglycerides (MCTs) are able to block beta-oxidation of fatty acids and reduce lipid peroxidation, but the MCT effects in steatosis are still controversial. Objective: The aim of this study was to assess the implications of high-fat diet (HF+) with fish oil or with MCT oil in the development of hepatic steatosis, liver fatty acid profile and oxidative stress markers in rats. Methodology: Fifty wistar male rats were divided into 5 groups. The animals had free access to food and water for 45 days. The first 15 days was dedicated for adaptation to high-fat diet. The HF+AF group received high-fat diet with 50% of animal fat and the other high-fat diets were made with 35% of animal fat plus 15% of other types of fat: soybean oil (HF+SO), MCT oil (HF+MCT) and fish oil (HF+FO). Results: The high-fat groups had higher hepatic total fat and triglycerides accumulation and only the groups HF+AF and HF+MCT had higher accumulation of hepatic cholesterol compared to control. The HF+MCT group had the highest percentage of hepatic fat accumulation and an exacerbated triglyceride accumulation in the liver among HF+ groups. The serum total cholesterol decreased in groups HF+MCT and HF+FO compared with the control group. The highest incorporation of hepatic fatty acids EPA and DHA in the HF+FO group contributed to the increased fatty acids peroxidizability index and total and free hepatic TBARS and depletion of hepatic vitamin E. The biggest ratio SFA/PUFA of liver fatty acids observed in the HF+MCT group contributed to the preservation of hepatic antioxidants. The alanine aminotransferase is a liver damage marker and was increased in all high-fat groups. Conclusions: The high-fat diet was effective to increase the hepatic fat concentration. The consumption of MCT oil can increase the hepatic lipid concentration and hepatic antioxidants. There was a significant increase in hepatic lipid peroxidation in the HF+FO group, although hepatic cholesterol and triglycerides were decreased.

Ulcerative colitis (UC) is a chronic disease of the colon or large intestine that causes inflammation and ulceration of the inner lining of the colon and rectum. In patients with ulcerative colitis, the body’s immune system overreacts and the body mistakes food, bacteria or other internal materials in the colon for an invading substance. The immune system attacks the material, thus irritating the colon. Limited knowledge of inflammatory conditions coupled with a narrow range of therapeutic options necessitates investigating the role of natural products. This study describes the effect of natural coconut oil on chemically-induced acute and chronic disease in mice. Ulcerative colitis was induced in four groups (5 mice per group) of 10-week-old female C57BL/6 mice by exposing them to 2.5-3% dextran sulfate sodium (DSS) for 5 and 29 days in the acute and chronic models, respectively. Coconut oil treatment was given via food containing 5% coconut oil to three diseased groups in three different regimens: one, preventive group receiving treatment prior to disease induction (14 d in acute; 28 d in chronic); two, simultaneous group receiving treatment simultaneous to disease induction; and three, regular treatment group receiving treatment after the disease induction –until termination of the experiment (14 d in acute; 60 d in chronic). Coconut food was replaced by the regular chow in the disease and water control groups. Clinical symptoms (diarrhea, occult blood, anal bleeding and body weight change) and the size of the isolated colon were recorded for comparison between experimental and control groups. Groups receiving coconut food displayed remissions in clinical markers of the disease. Improvements in clinical symptoms, histopathology, as well as cytokine activities were observed in both models, but the effects were more significant on the basis of standard error in the chronic model.