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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.
21

Colon Cancer Chemoprotection through Epigenetic Effects of a Fish Oil/Pectin Diet

Cho, Young Mi 2012 August 1900 (has links)
Accumulated genetic and epigenetic abnormalities contribute to the development of colon cancer. We have shown that a combination of fish oil (containing decosahexaenoic acid, DHA, 22:6 n-3) and pectin (fermented to butyrate by colonic microflora) is protective against colon carcinogenesis in part by regulating the expression of genes involved in apoptosis, leading to apoptosis induction. To determine how FO/P enhances apoptosis, we measured the expression of genes involved in apoptosis. We performed a pathway analysis on differentially expressed genes identified at three times during colon tumorigenesis: initiation, aberrant crypt foci (ACF) formation, and tumor stage, and compared these results with phenotypic observations at those times. At initiation, FO/P down-regulated the expression of genes involved with cell adhesion and enhanced apoptosis compared with corn oil/cellulose (CO/C). At the ACF stage, expression of genes involved in cell cycle regulation was modulated by FO/P and proliferation was reduced in FO/P rats compared with CO/C rats. FO/P increased apoptosis and the expression of genes that promote apoptosis at the tumor endpoint compared with CO/C. We next determined if changes in expression of genes involved in apoptosis by FO/P are associated with changes in promoter methylation of a key apoptosis regulator, Bcl-2. Genomic DNA was isolated from carcinogen-induced colon tumors and non-involved tissues. FO/P increased Bcl-2 promoter methylation in tumor tissues and colonocyte apoptosis relative to those observed with CO/C. A negative correlation between Bcl-2 DNA methylation and Bcl-2 mRNA levels was observed in the tumors. Additionally, we examined gene specific promoter methylation of 24 apoptosis-related genes using human colon cancer cells. Cells were treated with DHA or linoleic acid (18:2 n-6), and select cultures were also treated with butyrate. The combination of DHA and butyrate led to a significant reduction in the methylation of pro-apoptotic genes and an increase in apoptosis. These data suggest that part of the mechanisms involved in the induction of apoptosis by FO/P may be through epigenetic regulation of genes involved in apoptosis throughout colon carcinogenesis.
22

New insights into appetite, inflammation and the use of fish oil in hemodialysis patients

Zabel, Rachel Eve January 2009 (has links)
Protein-energy wasting (PEW) is commonly seen in patients with chronic kidney disease (CKD). The condition is characterised by chronic, systemic low-grade inflammation which affects nutritional status by a variety of mechanisms including reducing appetite and food intake and increasing muscle catabolism. PEW is linked with co-morbidities such as cardiovascular disease, and is associated with lower quality of life, increased hospitalisations and a 6-fold increase in risk of death1. Significant gender differences have been found in the severity and effects of several markers of PEW. There have been limited studies testing the ability of anti-inflammatory agents or nutritional interventions to reduce the effects of PEW in dialysis patients. This thesis makes a significant contribution to the understanding of PEW in dialysis patients. It advances understanding of measurement techniques for two of the key components, appetite and inflammation, and explores the effect of fish oil, an anti-inflammatory agent, on markers of PEW in dialysis patients. The first part of the thesis consists of two methodological studies conducted using baseline data. The first study aims to validate retrospective ratings of hunger, desire to eat and fullness on visual analog scales (VAS) (paper and pen and electronic) as a new method of measuring appetite in dialysis patients. The second methodological study aims to assess the ability of a variety of methods available in routine practice to detect the presence of inflammation. The second part of the thesis aims to explore the effect of 12 weeks supplementation with 2g per day of Eicosapentaenoic Acid (EPA), a longchain fatty acid found in fish oil, on markers of PEW. A combination of biomarkers and psychomarkers of appetite and inflammation are the main outcomes being explored, with nutritional status, dietary intake and quality of life included as secondary outcomes. A lead in phase of 3 months prior to baseline was used so that each person acts as their own historical control. The study also examines whether there are gender differences in response to the treatment. Being an exploratory study, an important part of the work is to test the feasibility of the intervention, thus the level of adherence and factors associated with adherence are also presented. The studies were conducted at the hemodialysis unit of the Wesley Hospital. Participants met the following criteria: adult, stage 5 CKD on hemodialysis for at least 3 months, not expected to receive a transplant or switch to another dialysis modality during the study, absence of intellectual impairment or mental illness impairing ability to follow instructions or complete the intervention. A range of intermediate, clinical and patient-centred outcome measures were collected at baseline and 12 weeks. Inflammation was measured using five biomarkers: c-reactive protein (CRP), interleukin-6 (IL6), intercellular adhesion molecule (sICAM-1), vascular cell adhesion molecule (sVCAM-1) and white cell count (WCC). Subjective appetite was measured using the first question from the Appetite and Dietary Assessment (ADAT) tool and VAS for measurements of hunger, desire to eat and fullness. A novel feature of the study was the assessment of the appetite peptides leptin, ghrelin and peptide YY as biomarkers of appetite. Nutritional status/inflammation was assessed using the Malnutrition-Inflammation Score (MIS) and the Patient-Generated Subjective Global Assessment (PG-SGA). Dietary intake was measured using 3-day records. Quality of life was measured using the Kidney Disease Quality of Life Short Form version 1.3 (KDQOL-SF™ v1.3 © RAND University), which combines the Short-Form 36 (SF36) with a kidney-disease specific module2. A smaller range of these variables was available for analysis during the control phase (CRP, ADAT, dietary intake and nutritional status). Statistical analysis was carried out using SPSS version 14 (SPSS Inc, Chicago IL, USA). Analysis of the first part of the thesis involved descriptive and bivariate statistics, as well as Bland-Altman plots to assess agreement between methods, and sensitivity analysis/ROC curves to test the ability of methods to predict the presence of inflammation. The unadjusted (paired ttests) and adjusted (linear mixed model) change over time is presented for the main outcome variables of inflammation and appetite. Results are shown for the whole group followed by analyses according to gender and adherence to treatment. Due to the exploratory nature of the study, trends and clinical significance were considered as important as statistical significance. Twenty-eight patients (mean age 61±17y, 50% male, dialysis vintage 19.5 (4- 101) months) underwent baseline assessment. Seven out of 28 patients (25%) reported sub-optimal appetite (self-reported as fair, poor or very poor) despite all being well nourished (100% SGA A). Using the VAS, ratings of hunger, but not desire to eat or fullness, were significantly (p<0.05) associated with a range of relevant clinical variables including age (r=-0.376), comorbidities (r=-0.380) nutritional status (PG-SGA score, r=-0.451), inflammatory markers (CRP r=-0.383; sICAM-1 r=-0.387) and seven domains of quality of life. Patients expressed a preference for the paper and pen method of administering VAS. None of the tools (appetite, MIS, PG-SGA, albumin or iron) showed an acceptable ability to detect patients who are inflamed. It is recommended that CRP should be tested more frequently as a matter of course rather than seeking alternative methods of measuring inflammation. 27 patients completed the 12 week intervention. 20 patients were considered adherent based on changes in % plasma EPA, which rose from 1.3 (0.94)% to 5.2 (1.1)%, p<0.001, in this group. The major barriers to adherence were forgetting to take the tablets as well as their size. At 12 weeks, inflammatory markers remained steady apart from the white cell count which decreased (7.6(2.5) vs 7.0(2.2) x109/L, p=0.058) and sVCAM-1 which increased (1685(654) vs 2249(925) ng/mL, p=0.001). Subjective appetite using VAS increased (51mm to 57mm, +12%) and there was a trend towards reduction in peptide YY (660(31) vs 600(30) pg/mL, p=0.078). There were some gender differences apparent, with the following adjusted change between baseline and week 12: CRP (males -3% vs females +17%, p=0.19), IL6 (males +17% vs females +48%, p=0.77), sICAM-1 (males -5% vs females +11%, p=0.07), sVCAM-1 (males +54% vs females +19%, p=0.08) and hunger ratings (males 20% vs females -5%, p=0.18). On balance, males experienced a maintainence or reduction in three inflammatory markers and an improvement in hunger ratings, and therefore appeared to have responded better to the intervention. Compared to those who didn’t adhere, adherent patients maintained weight (mean(SE) change: +0.5(1.6) vs - 0.8(1.2) kg, p=0.052) and fat-free mass (-0.1 (1.6) vs -1.8 (1.8) kg, p=0.045). There was no difference in change between the intervention and control phase for CRP, appetite, nutritional status or dietary intake. The thesis makes a significant contribution to the evidence base for understanding of PEW in dialysis patients. It has advanced knowledge of methods of assessing inflammation and appetite. Retrospective ratings of hunger on a VAS appear to be a valid method of assessing appetite although samples which include patients with very poor appetite are required to confirm this. Supplementation with fish oil appeared to improve subjective appetite and dampen the inflammatory response. The effectiveness of the intervention is influenced by gender and adherence. Males appear to be more responsive to the primary outcome variables than females, and the quality of response is improved with better adherence. These results provide evidence to support future interventions aimed at reducing the effects of PEW in dialysis patients.
23

The Effect of Supplementing Grazing Dairy Cattle Diets with Fish Oil and Linseed Oil on Milk CLA and Omega-3 Fatty Acid Content

Holmes-Miller, Leah 01 January 2009 (has links)
AN ABSTRACT OF THE THESIS OF TITLE: THE EFFECT OF SUPPLEMENTING GRAZING DAIRY CATTLE DIETS WITH FISH OIL AND LINSEED OIL ON MILK CLA AND OMEGA-3 FATTY ACID CONTENT In the recent years, there has been considerable interest in the potential health-promoting properties of both conjugated linoleic acid (cis-9, trans-11 CLA), a fatty acid produced naturally in ruminant animals, and omega-3 fatty acids. The objectives of this research were to evaluate the effects of supplementing grazing dairy cows' diet with fish oil(FO)-linseed oil(LO) blend on milk cis-9, trans-11 CLA and omega-3 fatty acids milk content. In experiment one, fourteen lactating Holstein cows were randomly assigned to one of two treatment groups (7 cows/treatment) and fed either a control or oil supplemented diet for 21 d. Treatment groups were: 1) confinement cows with free access to corn silage and hay mix plus 10 kg/d (DM basis) grain mix supplementation (CONT), or 2) grazing cows with free access to grass pasture plus 10 kg/d grain mix supplementation containing 300 g FO plus 700 g LO (FOLO). Milk samples were collected during the last 3 d of the study and analyzed for chemical and fatty acid composition. Milk production (37.05 vs. 37.29 kg/d), milk protein percentages (3.16 vs. 3.21), and milk protein yield (1.05 vs. 1.25 kg/d) were not affected (P > 0.05) by treatment diets. Milk fat percentages (3.71 and 2.28) and yield (1.25 and 0.87 kg/d) were higher (P < 0 .05) with the CONT group. The concentrations of cis-9, trans-11 CLA (0.29 vs. 2.56 g/100g fatty acid) and vaccenic acid (VA; 0.81 vs. 7.14 g/100g fatty acid) in milk fat were higher (P < 0.05) with the FOLO group. The concentrations of milk omega-3 C18:3n3, C20:5n3, and C22:6n3 were also higher (P < 0.05) with the FOLO group. In experiment two, eighteen lactating Holstein cows who were randomly assigned to one of three treatment groups for 21 d. Treatment groups were 1) indoor cows with free access to corn silage and alfalfa hay plus 10 kg/d (DM basis) grain mix supplementation (CONT), 2) indoor cows with free access to corn silage and alfalfa hay plus 10 kg/d grain mix supplementation containing 300 g FO plus 700 g LO (FOLO), and 3) grazing cows with free access to grass pasture plus 10 kg/d grain mix supplementation containing 300 g FO plus 700 g LO (FOLOP). Milk samples were taken from each cow during the last 3 d of the study. Milk production, milk protein percentages and milk protein yield were not affected (P > 0.05) by treatment diets. Milk fat percentages (3.55, 2.85, and 2.39) and yield (1.20, 0.98, and 0.84 kg/d) were lower (P < 0 .05) among the oil supplemented cows with cows on the FOLOP diet having the lowest values. Concentrations of milk cis-9 trans-11 CLA (0.33, 1.78, and 2.94 g/100g fatty acid) and VA (0.83, 5.09, and 7.15 g/100g fatty acid) were higher (P < 0 .05) among the oil supplemented cows and they were highest with cows on the FOLOP diet. Concentration of milk omega-3 fatty acids (0.5, 1.11, and 1.47 g/100g fatty acid) were higher (P < 0.05) among oil supplemented cows and was also highest for cows on the FOLOP diet. In conclusion cows fed diets containing the FO-LO blend resulted in higher milk concentrations of cis-9, trans-11 CLA and omega-3 fatty acids when compared to cows fed the CONT diet. However, greatest increases in cis-9, trans-11 CLA and omega-3 concentrations in the milk were achieved when the FO-LO blend was fed along with grazing.
24

Impact of alternative, non-fish oil dietary lipid sources and subsequent 'finishing' on growth and tissue long-chain polyunsaturated retention in cobia, Rachycentron canadum

Woitel, Franklin 01 August 2013 (has links)
Cobia (Rachycentron canadum) aquaculture is poised for expansion, due in part to rapid growth rate, tolerance of culture conditions, and high market value of this species. Similar to other carnivorous marine fishes, the high monetary cost and long-range unsustainability of reliance on fish oil as the principle lipid source for cobia feeds necessitates evaluation of alternative lipid sources to spare or replace fish oil. Unfortunately, alternative lipid-based feeds may affect production performance, and typically yield fillets with reduced levels of long-chain polyunsaturated fatty acids (LC-PUFAs) such as docosahexaenoic acid (DHA, 22:6n-3). Recent research has indicated that diets rich in saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs), coupled with the application of so-called "finishing feeds" (feeds containing elevated levels of fish oil relative to grow-out feeds) at the end of the production cycle, may limit or attenuate these effects of fish oil sparing. Accordingly, I conducted two trials to evaluate the usefulness of alternative lipids and finishing in cobia culture. In the first trial, I assessed growth performance and tissue fatty acid composition of juvenile cobia fed diets (~11% lipid, ~48% protein) containing fish oil (control), or 50/50 blends of fish oil and alternative lipids (beef tallow, pork lard, partially and fully hydrogenated soy oils, and traditional soy oil) supplemented with an algal meal (to meet the 22:6n-3 requirement of cobia) for 8 weeks. Although minor differences were observed in feed intake, growth performance was otherwise equivalent among the dietary groups. Tissue fatty acid composition varied significantly among treatments, however, with alternative lipids containing higher levels of saturated (SFAs) and monounsaturated fatty acids (MUFAs) yielding tissue profiles that were most similar to those associated with the fish oil-based control feed. Although beef tallow and hydrogenated soybean oil were largely equivalent in terms of growth performance and fatty acid profile change, beef tallow was selected for further evaluation because of its low cost. In the second trial, beef tallow replaced fish oil in feeds at one of four substitution levels: 0% (100% fish oil), 33%, 67%, or 100% tallow (with algal 22:6n-3 meal included in all feeds as before). Juvenile cobia were raised on these feeds for 8 weeks, then switched to the 100% fish oil-based control feed for an 8-week finishing period. During finishing, subsamples of fish were collected every 2 weeks to quantify changes in tissue fatty acid profile over time as a result of finishing. In the second trial, the overall similarity of tissue fatty profiles to those in the 100% fish oil control treatment increased over the course of finishing, mostly as a result of declines in SFAs and MUFAs. These results suggest that SFA and MUFA-rich lipids, such as fully hydrogenated soy oil and beef tallow, are effective and strategically valuable as partial substitutes for fish oil in cobia feeds, and that finishing is at least partially effective in restoring cobia tissue fatty acid composition to a state approximating that of cobia fed only fish oil as dietary lipid.
25

EFFECTS OF STEARIDONIC ACID-ENRICHED SOYBEAN OIL ON METABOLIC PROFILE AND FATTY ACID COMPOSITION IN LEAN AND OBESE ZUCKER RATS

Casey, John 01 December 2013 (has links)
Background, Consumption of marine-based oils high in omega-3 polyunsaturated fatty acids (n3PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is known to protect against obesity-related pathologies. It is less clear whether traditional vegetable oils with high omega-6 polyunsaturated fatty acid (n6PUFA) content exhibit similar therapeutic benefits. As such, this study examined the metabolic effects of a plant-based n3PUFA, stearidonic acid (SDA), in polygenic obese rodents. Methods, Lean (LZR) and obese Zucker (OZR) rats were provided either a standard westernized control diet (CON) with a high n6PUFA to n3PUFA ratio (i.e., 16.2/1.0) or experimental diet modified with flaxseed (FLAX), menhaden (FISH), or SDA oil that resulted in n6PUFA to n3PUFA ratios of 1.7/1.0, 1.3/1.0, and 1.0/0.8, respectively. Results, After 12 weeks, total adiposity, dyslipidemia, glucose intolerance, and hepatic steatosis were all greater, whereas n3PUFA content in liver, adipose, and muscle was lower in OZR vs. LZR rats. Obese rodents fed modified FISH or SDA diets had lower serum lipids and hepatic fat content vs. CON. The omega-3 index (i.e., ÓEPA + DHA in erythrocyte membrane) was 4.0, 2.4, and 2.0-fold greater in rodents provided FISH, SDA, and FLAX vs. CON diet, irrespective of genotype. Total hepatic n3PUFA and DHA was highest in rats fed FISH, whereas both hepatic and extra-hepatic EPA was higher with FISH and SDA groups. Conclusions, these data indicate that SDA oil represents a viable plant-derived source of n3PUFA, which has therapeutic implications for several obesity-related pathologies.
26

Fish Oil Supplementation and Cardiovascular Disease Risk in Individuals of Blood Type A and Blood Type O

January 2014 (has links)
abstract: The omega-3 fatty acids in fatty fish and fish oil, eicosapentanoic acid (EPA) and docosahexanoic acid (DHA), have been associated with a reduction in risk for cardiovascular disease. Blood type is a known contributor to risk for cardiovascular events. This study evaluated the effect of fish oil supplements on cardiovascular risk markers in adults with blood types A or O. An 8-week parallel-arm, randomized, double-blind trial was conducted in healthy adult men and women with either blood type A (BTA) or blood type O (BTO). Participants were randomized to receive fish oil supplements (n=10 [3 BTA/7 BTO]; 2 g [containing 1.2 g EPA+DHA]/d) or a coconut oil supplement (n=7 [3 BTA/4 BTO]; 2 g/d). Markers that were examined included total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), high-sensitivity C-reactive protein (hsCRP), and hemoglobin A1C (HbA1C). Results indicated that the percent change in LDL cholesterol was significantly greater in the coconut oil group vs the fish oil group (-14.8±12.2% vs +2.8±18.9% respectively, p=0.048). There were no other significant differences between treatment groups, or between blood types A and O, for the other cardiovascular risk markers. Further research with a larger and more diverse sample may yield a more conclusive result. / Dissertation/Thesis / M.S. Nutrition 2014
27

Impact of Omega-3 Fatty Acid Supplementation on Baseline Levels of Inflammatory Markers in the General Population

Nhan, Alex 01 January 2017 (has links)
Inflammation is a complex physiological response normally initiated by the innate immune system, often as a response to exposure to otherwise harmful stimuli. While generally useful in humans as a protective response to foreign matter, chronically elevated quantities of associated inflammatory factors C-reactive protein, TNF-alpha, IL-6, and IL-1beta have been linked in literature with decreased overall lifespan and well-being in humans via inflammatory processes. It is possible that by lowering these associated factors, increased well-being and lifespan may be experienced by the general population. One common health supplement with such promise is fish oil, which, through compounds eicosapentaenoic acid and docosahexaenoic acid, has been observed to decrease levels of secreted inflammatory markers in cell culture. In addition, molecular pathways have since been discovered which demonstrate possible means for which this physiological response may occur. However, despite the promise of such health benefits, studies attempting to discern the impact EPA/DHA supplementation has on inflammatory markers within humans have since emerged with mixed results. The aim of this study is to provide a meta-analysis across a number of studies to determine whether or not an impact exists through EPA/DHA supplementation in healthy populations, and if one exists, to what degree the respective inflammatory factors may be lowered.
28

Influência da adição de fontes ricas em PUFAs n-3 na dieta de galinhas sobre a composição lipídica do ovo / Influence of the addition of PUFAs n-3 rich sources in laying hens diet on lipid composition of the egg

Carvalho, Paulo Reis de 22 February 2006 (has links)
A presente pesquisa foi conduzida utilizando-se 288 galinhas poedeiras da linhagem Hisex White com 32 semanas de idade, pelo período de 10 semanas, com o objetivo de estudar o enriquecimento da gema do ovo em ácidos graxos a partir de rações suplementadas com óleo de peixe (OP) ou alga marinha (AM) em cinco níveis de DHA (120, 180, 240, 300 e 360 mg/100 g dieta). Foi aplicado modelo fatorial 2 x 5, inteiramente casualizado, com três repetições de oito aves por tratamento, de modo a constituir os grupos: OP120, OP180, OP240, OP300, OP360, AM120, AM180, AM240, AM300 e AM360. Um grupo controle submetido à ração basal de milho e soja (CON) e outro, acrescido de AM, contendo 420 mg de DHA/100 g dieta (AM420) foram também utilizados. Os seguintes parâmetros foram avaliados: postura, peso do ovo, consumo alimentar, conversão alimentar, qualidade externa e interna dos ovos e qualidade organoléptica dos mesmos. O peso médio do ovo assinalado para o grupo CON (63,30 g) decresceu linearmente de forma significativa (Y = - 0,0051X + 63,8560, R2 = 0,97) em resposta à suplementação de níveis crescentes de DHA da fonte OP, atingindo valor mínimo de 62,13 g no grupo OP360. O índice de postura das aves de 88,10% (CON) não foi influenciado pelas fontes de DHA na ração. A qualidade interna do ovo, avaliada em unidades Haugh, apresentou melhora significativa (P&lt;0,05) com a adição de teores crescentes de AM igual ou superior a 1% na dieta das aves. Quanto aos teores de DHA na gema do ovo de aves suplementadas com OP, foi observado aumento significativo de 22,64 mg/ gema (CON), para 187,91 mg/ gema no grupo OP360. Os PUFAs n-3 apresentaram acréscimo significativo no contraste entre CON (62,16 mg/gema) e OP360 (218,62 mg/gema). Para a fonte AM, as médias de DHA também mostraram linearidade (Y = 0,23X + 1,27, R2 = 0,86), oscilando entre 22,64 mg/gema (CON) e 149,75 mg/gema (AM420), enquanto que o total de PUFAs n-3 oscilou de 104,18 mg/gema (AM120) a 175,32 mg/gema (AM420). O inverso ocorreu com os ácidos araquidônico, linoléico e PUFAs n-6 que mostraram decréscimos significativos (P&lt;0,05) com o aumento de OP na dieta, variando, respectivamente, de 98,71 mg, 987,70 mg e 1108,92 mg/ gema na dieta CON a 38,87 mg, 734,22 mg e 802,79 mg/ gema, para o grupo OP360. O percentual de incorporação de DHA na gema dos ovos decresceu linearmente com o aumento dos níveis de DHA na ração suplementada com OP e AM, de 85,11% (OP120) e 65,28% (AM120) para 49,45% (OP360) e 34,06% (AM420). Melhora significativa (P&lt;0,05) foi consignada na relação n-6/n-3, variando de 17,50 no grupo CON para 3,72 e 6,36 para tratamentos OP360 e AM420, respectivamente. A avaliação sensorial não detectou qualquer sabor ou odor estranho nos ovos dos diferentes tratamentos ou fontes utilizados, exceto para a análise qualitativa do grupo OP360 onde foi detectado grau de intensidade regular de sabor de peixe, diferindo significativamente (P&lt;0,05) do grupo CON. / This experiment was conducted using two hundreds eighty eight 32-wk-old Hisex White laying hens for a period of ten weeks, with the objective of studying the fatty acid enrichment of the egg yolk of hens fed diets supplemented with fish oil (OP) or marine algae (AM) to provide five levels of DHA (120, 180, 240, 300 and 360 mg/100 g diet) for each source. A 2 X 5 completely randomized factorial design with three replicates of eight birds per treatment was applied in order to have the following groups: OP120, OP180, OP240, OP300, OP360, AM120, AM180, AM240, AM300 and AM360. A control group submitted to a corn/soy basal diet (CON) and another one supplemented with AM at the level of 420 mg of DHA/100 g diet (AM420) were also used. Egg production, egg weight, feed intake, feed conversion, external and internal egg quality and the organoleptic quality of the eggs were evaluated. The egg weight mean obtained for group CON (63.30 g), decreased linearly (Y = - 0.0051X + 63.8560, R2 = 0.97) as the supplemented DHA levels from the OP source increased, reaching the lowest egg weight mean of 62.13 g for the group OP360. The egg production of the control group hens (88.10%) was not influenced by the source of DHA. The internal quality of the egg evaluated by Haugh units presented significant improvement (P&lt;0.05) with the increase of the AM source to 1% or more. The amounts of DHA into the egg yolk in birds fed OP diets, were significantly increased from 22.64 mg/egg yolk (CON), to 187.91 mg/egg yolk (OP360). The egg yolk PUFAs n-3 of the control group (62.16g) increased significantly as compared to the OP360 group (218.62 mg/yolk). The AM source showed DHA means also linear (Y = 0.23X + 1.27, R2 = 0.86), ranging from 22.64 mg/yolk (CON) to 149.75 mg/yolk (AM420), while the PUFAs n-3 ranged from 104.18 mg/yolk (AM120) to 175.32 mg/yolk (AM420). The araquidonic acid, linoleic acid and PUFAs n-6 showed significant decrease (P&lt;0.05) with the increase of OP into the diet, ranging from 98.71 mg, 987.70 mg and 1108.92 mg/egg yolk for the CON group to 38.87 mg, 734.22 mg and 802.79 mg/egg yolk, for the OP360 group. The percentage of DHA incorporation into the egg yolk decreased linearly as the DHA levels increased into the diet. Thus, for the OP and AM sources, mean values of 85.11% (OP120) and 65.28% (AM120) decreased to 49.45% (OP360) and 34.06% (AM420). Significant improvement (P&lt;0.05) was found in the ratio n-6/n-3, ranging from17.50 (CON) to 3.72 (OP320) and 6.36 (AM420). The sensorial evaluation of eggs did not detect any different flavor or odor in eggs among treatments or sources, except for the qualitative analysis of group OP360 which showed fish flavor, significantly different (P&lt;0.05) from the control group.
29

The impact of n-3 PUFA supplementation on human skeletal muscle metabolism

McGlory, C. January 2014 (has links)
The time course of this increase in muscle n-3 PUFA composition and anabolic protein expression is currently unknown. In Chapter 2 of this thesis ten healthy male participants consumed 5g.d-1 of n-3 PUFA-enriched fish oil for 4 weeks. Muscle biopsies samples were collected in the fasted, rested state 2 weeks prior, immediately before (Week 0), at Week 1, Week 2 and Week 4 after initiation of fish oil supplementation for assessment of changes in lipid composition and expression of anabolic signalling proteins over time. Muscle lipid profile, (% total n-3 PUFA/total fatty acids) increased from W0 to W2 (3.8 ± 0.2 to 5.1 ± 0.3 %) and continued to rise at W4 (6.7 ± 0.4 %). Total protein content of FAK increased from W0 to W4 (3.9 ± 1.5 fold) whereas total mTOR was increased from W0 at W1 (2.4 ± 0.6 fold) with no further significant increases at W2 and W4. For the first time this study demonstrates that oral fish oil consumption results in an increase of n-3 PUFA levels in human skeletal muscle that is associated with increases in the expression of anabolic signalling proteins. Our understanding of the anabolic signalling process that underpins muscle protein synthesis has been advanced by the application of the WB technique. However, the semi-quantitative nature and poor dynamic range associated with the WB technique may lead to incongruence regarding the molecular response of skeletal muscle to anabolic stimulation. Chapter 3 of this thesis developed and applied a quantitative in vitro [γ-32P] ATP kinase assay (KA) alongside a traditional WB methodology to assess p70S6K1 signalling responses in human skeletal muscle to RE and protein feeding. Following validation in tissue culture with rapamycin and optimization of the assay in human skeletal muscle, this methodology was tested in a physiologically relevant context. In this regard, six males performed unilateral resistance exercise (RE) followed by the consumption of 20 g of protein. Skeletal muscle biopsies were obtained at pre-RE, at 1 h and 3 h post-RE. In response to RE and protein consumption, p70S6K1 activity was significantly increased from pre-RE at 1 h and 3 h post-RE (8.84 ± 0.78 to 17.18 ± 2.62 and 15.62 ± 3.12 µU/mg). However, phosphorylated p70S6K1thr389 was not significantly elevated. To assess if a combined stimulus of RE and feeding can influence AMPK activity we directly measured AMPK activity. AMPK activity was suppressed from pre-RE at 3 h post-RE (24.15 ± 1.6 to 15.64 ± 1.07 mU/mg), whereas phosphorylated ACCser79 was unchanged. These data therefore highlight the utility of the KA to study skeletal muscle plasticity. Previous studies have shown that ingestion of n-3 PUFA potentiates the phosphorylation of mTORC1 and associated kinases in response to nutrition. However, no study has identified whether n-3 PUFA supplementation potentiates anabolic kinase activity when RE is performed prior to nutrient provision. In Chapter 4 of this thesis, twenty healthy males consumed 5g.d-1 of either fish oil (FO) or coconut oil (CO) capsules for 8 weeks. Muscle biopsy samples were collected in the fasted, rested state before and after 8 weeks of supplementation for assessment of changes in lipid composition. Following 8 weeks of supplementation muscle samples also were obtained at rest (Rest), post RE in both the exercise leg (Post-RE) and the rested leg (Pre-FED) and also at 3 h post RE and protein feeding from both the exercise leg (3 h post-REF) and rested leg (3 h post-FED). There was a 2-fold increase in muscle (5.53 ± 0.3 to 11.16 ± 0.45 % of total fatty acids) n-3 PUFA composition after supplementation in the FO group but no change in the CO group. Following supplementation there was an increase in p70S6K1 activity at 3 h post-REF from Rest in the CO group (5.6 ± 1.4 to 12.2 ± 2.1 µU/mg) but no change in the FO group. In the CO group, AMPKα2 was significantly increased at Post-RE from Rest (3.7 ± 0.7 to 9.9 ± 2.0 mU/mg). These data show that 8 weeks of n-3 PUFA enriched fish oil supplementation suppresses the activity of p70S6K1 in response to RE and protein feeding.
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A business plan for incorporating a bio-diesel refinery into the value chain of a pelagic fish-processing plant

Du Preez, A. J. 12 1900 (has links)
Thesis (MBA (Business Management))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Through the continual pursuit to reduce wastage through converting unmarketable by-products into a form that can be sold or used, it was established that an opportunity was available to refine poor-quality fish oil into a fuel source for internal use by a company. By commissioning a biodiesel refinery at the pelagic fish-processing facility of Pioneer Fishing (Pty) Ltd, it will be possible to refine the fish oil into biodiesel and easily distribute the fuel to the fishing vessels or the trucks used for the catching and transportation of pelagic fish. South African legislation is promoting small-scale biodiesel plants by reducing the taxes and levies payable on biodiesel sold by those refineries. The aim of this research report is to provide Pioneer Fishing (Pty) Ltd with a business plan to motivate the commissioning of a small-scale biodiesel plant to process the waste fish oil into a useable energy source to fuel the fishing vessels and trucks. / AFRIKAANSE OPSOMMING: Die voortdurende strewe na minder vermorsing deur onbemarkbare neweprodukte in ʼn verhandelbare of bruikbare vorm om te sit, het die geleentheid uitgewys om visolie van ʼn swak gehalte tot ʼn brandstof vir interne gebruik deur ‟n maatskappy te raffineer. Deur ʼn biodieselraffinadery by die diepseevisverwerkingsfasiliteit van Pioneer Fishing (Edms) Bpk in gebruik te neem, sal die afvalvisolie van dié aanleg tot biodiesel geraffineer kan word. Die biodiesel sal betreklik maklik beskikbaar gestel kan word aan die vaartuie en die vragmotors wat vir die vangs en vervoer van die diepseevis gebruik word. Heersende Suid-Afrikaanse wetgewing moedig juis kleinskaalse biodieselaanlegte aan deur ʼn korting toe te staan op die belasting en heffings op die biodiesel van sodanige raffinaderye. Hierdie navorsingsverslag het ten doel om Pioneer Fishing (Edms) Bpk van ʼn sakeplan te voorsien ter motivering van die ingebruikneming van ʼn kleinskaalse biodieselaanleg om die afvalvisolie tot ʼn bruikbare energiebron te verwerk waarmee die visvaartuie en -vragmotors aangedryf kan word.

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