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Shelf-life extension studies on an omega-3 enriched breakfast cerealBagdan, Galen Corey. January 2000 (has links)
A granola-type, omega-3-rich breakfast cereal prototype was developed using ground flaxseed as the principal source of linolenic acid (1.8% w/w). Other ingredients included rolled oats, yellow sugar, honey, sliced almonds, and canola oil. The focus of the research investigation was to apply and study the addition of an antioxidant (AO) and the use of Modified Atmosphere Packaging (MAP) on shelf-life extension of the enriched cereal. Granola samples, both with and without AO (300ppm of 70% mixed tocopherols), were packaged in air, and under the two atmospheres achieved by nitrogen flushing (MA 1) and an oxygen scavenger (MA2). Samples were stored at either 21 or 35°C. / Shelf-life was terminated when products reached a thiobarbituric acid (TBA) value of 4.0 mg malonaldehyde/kg corresponding to a sensory score of 5 (on a hedonic scale of 10). (Abstract shortened by UMI.)
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Strategies for improving fatty acid profile of eggs for production of omega-3 enriched eggsAmini, Keyvan. January 2007 (has links)
Two experiments were carried out to evaluate the effects of Pearl Millet in combination with different levels of flaxseed and natural pigment (Oro Glo 15RTM) on quantity of n-3 fatty acids in eggs, laying performance and yolk pigmentation. In the first experiment, six different diet treatments were used for six weeks, with 24 hens per treatment (three birds per cage, eight cage replicates). Control diet was a corn-soybean meal diet, and diets containing 0, 2, 4, 8 or 12% ground flaxseed in which all the corn was replaced by pearl millet. In the second experiment, the diet treatments consisted of pearl millet and three inclusion levels of ground flaxseed (4%, 6% and 8%) and two levels (0.1% and 0.2%) of natural pigment in a factorial arrangement. The experiment lasted for twelve weeks, with 18 hens per treatment (three birds per cage, six cage replicates). In each of the experiments, all the diets were formulated to be isocaloric and isonitrogenous and to meet or exceed NRC requirements. Body weight of the birds and feed consumption were recorded at weekly (first experiment) and biweekly (second experiment) intervals. Number of eggs and egg mass produced were measured and recorded on a daily basis. At the end of each of the experiments, all the hens were euthanized to determine liver integrity. In both of the experiments, flock performance parameters were not different among treatments. In regard to egg traits, in the second experiment after 8 week of the start of the experiment, birds fed with diets containing 8% flaxseed produced significantly ( P < 0.05) smaller eggs compared to hens fed 4% flaxseed. Yolk pigmentation was lower (P < 0.05) for the eggs produced by hens fed diets containing pearl millet compared with those produced by feeding corn-based diet. However, 0.1% or 0.2% inclusion of the pigment both proved to be suitable to restore yolk pigmentation to marketable levels. No difference was observed among diets in regard to liver haemorrhage. Evaluation of FA profiles indicated that birds fed a diet containing PM as the sole grain source, and low levels of flaxseed (6%) can produce eggs with more than 350 mg/egg of n-3 FA, which is the lower standard to market eggs as "n-3 FA enriched". / Keywords: laying hens, pearl millet, flaxseed, natural pigment, flock performance, eggs, liver haemorrhage.
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The effect of the consumption of three types of dietary fish on cardiovascular risk predictorsPatton, Beverly D. 08 December 1992 (has links)
Epidemiological studies have suggested that the consumption
of fish may reduce the risk of cardiovascular disease.
Compared to the number of studies using fish oils, few
studies have used fish itself. Those which have used fish
have generally used fattier fish such as mackerel and salmon
as part of an uncontrolled diet. In this study, 23 healthy
men consumed 200g each of Chinook salmon, Dover sole, and
sablefish in a three-way crossover design for 18-day periods
with three-week washout periods in between. The diets had
the approximate composition of the 'Western' diet: 45%
carbohydrates, 36% fat, and 16% protein with the sole diet
containing 1.95 g omega-3 (n-3) fatty acids, the salmon diet
3.99 g n-3, and the sablefish diet 3.42 g n-3 fatty acids.
Serum total cholesterol (TC), high density lipoprotein
cholesterol (HDL-C), low density lipoprotein cholesterol
(LDL-C), triglycerides (TG), bleeding time (BT), blood
pressure (BP), platelet aggregation (PA) using ADP and
collagen as agonists, platelet fatty acid profiles (FAP), thromboxane B2 (TXB2) , and apolipoprotein B (Apo B) were
measured at the beginning and end of each period. TC, and
HDL-C, and TG changed significantly when compared to the
prefish diet while both LDL-C and apo B demonstrated diet
effect. LDL-C increased on both the salmon and sablefish
diets (p = 0.08) compared to the sole diet, and increased
approximately 15% on the former two diets compared to the
prefish diet. Bleeding time was significantly longer when
the salmon diet was consumed (p = 0.06). The impact of the
three diets on PA depended upon the agonist. With collagen,
only the sablefish diet decreased aggregation compared to
the prefish diet. When ADP was used, aggregation decreased
on both the fattier fish diets compared to the low fat fish
(sole). Similar results were demonstrated for TXB₂: the
fattier fish produced statistically equivalent decreases (p
= 0.06) among the diets, and lowered TXB₂ compared to the
prefish diet. There were no significant differences among
the diets for either systolic or diastolic BP though there
was a significant decrease (p = 0.01) in diastolic pressure
compared to the prefish diet when the salmon diet was
consumed. Platelet fatty acid profiles reflected diet
composition. / Graduation date: 1993
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Extraction and production of n-3 polyunsaturated fatty acid concentrate from Pacific sardines (Sardinops sagax)Okada, Tomoko 05 May 2006 (has links)
Graduation date: 2006
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Adverse developmental programming of the adult phenotype by fetal glucocorticoid excess and its prevention by postnatal dietary Omega-3 fatty acidsWyrwoll, Caitlin Sarah January 2007 (has links)
[Truncated abstract] Increased incidence of hypertension, insulin resistance, obesity and dyslipidemia, collectively referred to as the metabolic syndrome, has been linked to low birth weight, an indicator of a poor fetal environment. This association reflects developmental programming, a process by which organ systems are affected during early development such that disease states are more likely to emerge in adult life. Fetal glucocorticoid overexposure is thought to be a key factor that mediates developmental programming. Accordingly, maternal treatment with the synthetic glucocorticoid dexamethasone retards fetal growth and leads to delayed puberty, hypertension, hyperinsulinemia, and hyperleptinemia, either with or without increased adiposity, in adult offspring. Importantly, the postnatal environment can either amplify or attenuate the long-term outcome of developmental programming. The focus of this thesis was whether adverse developmental programming outcomes can be attenuated by the postnatal environment and thus provide therapeutic potential. Specifically, the effects of a postnatal diet rich in omega-3 fatty acids on glucocorticoid-induced developmental programming outcomes was investigated. ... The adipocyte phenotype was examined in Study 6, with hyperleptinaemia evident in offspring at 6 and 12 months of age in dexamethasone-exposed animals on a standard omega-3 diet, but this effect was prevented by a high omega-3 diet. The pattern of plasma leptin was paralleled by changes in leptin mRNA in retroperitoneal fat. Similarly, plasma levels of the inflammatory markers IL-6 and IL-1β were upregulated by prenatal glucocorticoid exposure and these were attenuated by postnatal dietary omega-3 fatty acids. Overall, omega-3 ingestion reduced adiposity, as indicated by measures of body composition. In conclusion, the studies presented in this thesis demonstrate for the first time that many of the detrimental effects of excess glucocorticoid exposure in utero on the adult phenotype can be attenuated by a postnatal diet rich in omega-3 fatty acids. This beneficial effect of omega-3 fatty acids was associated with a reversal of some (e.g. adiposal leptin) but not all (e.g. renal GR) 'programmed' changes in gene expression. These findings raise the possibility that dietary supplementation with omega-3 fatty acids may provide a viable therapeutic option for preventing and/or reducing adverse programming outcomes in humans.
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Polyunsaturated fatty acid metabolism in broiler chickens : effects of maternal diet /Bautista Ortega, Jaime. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2007-12-20. / Printout. Includes bibliographical references (leaves 121-127). Also available on the World Wide Web.
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The omega-3 fatty acid content of krill protein concentrate influences bioavailability, tissue deposition, peroxidation, and metabolism in young ratsBridges, Kayla Marie. January 2009 (has links)
Thesis (M.S.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains vii, 42 p. : ill. Includes abstract. Includes bibliographical references (p. 29-35).
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Marine oils : stabilization, structural characterization and omega-3 fatty acid concentration /Wanasundara, Udaya Nayanakantha, January 1996 (has links)
Thesis (Ph.D.)--Memorial University of Newfoundland, 1997. / Restricted until December 2000. Bibliography: leaves [252]-282.
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PROSTAGLANDIN E2 PATHWAY AS A TARGET TO PREVENT AND TREAT OVARIAN CANCER IN LAYING HENSEilati, Erfan 01 May 2014 (has links)
Chronic inflammation has been linked to cancer. Prostaglandin E2 (PGE2) is the most pro-inflammatory lipid and one of the downstream products of 2 isoforms of cyclooxygenase (COX) enzymes: COX-1 and COX-2. Although both COX isoforms have similar structure and function, they are encoded by different genes and show distinct expression patterns. COX-1 is expressed in most cells and tissues and remains constant under most physiologic conditions to play a housekeeping role whereas the COX-2 form is inducible and usually only expressed in response to various inflammatory stimuli. COX enzymes may be involved in both tumor establishment and maintenance of existing tumors. PGE2 exerts its effects on target cells by coupling to four subtypes of receptors which have been classified as EP1-4. Ovarian cancer is the most lethal gynecological malignancy and mainly occurs in older women. Prevention may be the best approach to reduce ovarian cancer. Ovarian cancer is the fifth leading cause of cancer death among women and the most lethal gynecological malignancy. There are at least 3 well established risk factors for ovarian cancer: age, family history and environmental factors. Ovarian cancer is mainly seen in older women when their ovaries are not reproductively functional. Close to half of the women with ovarian cancer (48%) are in the age group of 65 or older. Epidemiological and preclinical studies indicate that increased dietary intake of omega-3 fatty acids (OM-3FAs) reduces the incidence and growth of various cancers. Thus, increasing the consumption of OM-3FAs may be a nontoxic way to prevent or suppress ovarian cancer. Flaxseed is the richest vegetable source of omega-3 fatty acids which may be effective in the prevention of ovarian cancer. Fish oil is a source of OM-3FAs which may be effective in prevention of ovarian cancer. The main OM-6FA, Linoleic Acid (LA), is a direct precursor of the Arachidonic Acid (AA). Alpha-linolenic acid (ALA) is the main OM-3FA found in flax oil, whereas eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the OM-3FAs in fish oil. ALA is elongated to form EPA and DHA in the intestine. Celecoxib is a non-steroidal anti-inflammatory (NSAID) drug that selectively inhibits COX-2. There are evidences showing that Celecoxib has some anti-cancer properties. Progress in the treatment and prevention of ovarian cancer has been hampered due to the lack of an appropriate animal model and absence of effective chemo-prevention strategies. The domestic hens spontaneously develop ovarian adenocarcinomas that share similar histological appearance and symptoms such as ascites and metastasis with humans. Our first objective was to investigate the effect of flaxseed supplementation for one year on ovarian cancer and correlate its effects to expression of COX enzymes and concentrations of prostaglandins. White Leghorn hens were fed 10% flaxseed-enriched or standard diet for one year. The severity of ovarian cancer was determined by gross pathology and histology. COX-1 and COX-2 localization and protein and mRNA expression and PGE2 and PGE3 concentrations in ovaries were measured by Immunohistochemistry, western blot, quantitative real-time PCR and LC-MS-MS, respectively. The results demonstrated a significant reduction in late stage ovarian tumors in the flaxseed-fed hens compared with the control diet-fed hens. In correlation with decreased ovarian cancer severity, concentrations of PGE2 and expression of COX-2 were diminished in ovaries of flaxseed-fed hens. PGE3 concentrations were below the level of detection. The results demonstrated that in normal ovaries, COX-1 was localized to the granulosa cell layer surrounding the follicles and ovarian surface epithelium (OSE) whereas COX-2 protein was localized to the granulosa cell layer in the follicle. Extensive COX-1 and COX-2 protein expression was found throughout the ovarian carcinoma. Our findings suggest that the flaxseed-mediated reduction in the severity of ovarian cancer in hens is correlated to the reduction in PGE2 in the ovaries of flaxseed-fed hens. Since no effect on ovarian cancer incidence was detected after feeding the 2. 5 year old hens with 10% flaxseed for 1 year, we designed a long-term study using 6 month old hens. Our objectives were: 1) to examine the expression of COX enzymes and PGE2 levels in ovaries and correlate them to ovarian cancer and aging 2) to determine if long-term consumption of a flaxseed enriched diet decreases ovarian cancer severity and incidence in the laying hen and to investigate its potential correlation with the expression of COX enzymes and PGE2 concentration. White Leghorn hens were fed 10% flaxseed-enriched or standard diet for 4 years. The severity and incidence of ovarian cancer were determined by gross pathology and histology. COX-1 and COX-2 protein and mRNA expression and PGE2 concentrations in ovaries were measured by western blot, quantitative real-time PCR and ELISA, respectively. Our results indicated an increase in ovarian cancer incidence and expression of both COX enzymes in ovaries of older hens. In correlation with ovarian cancer incidence and COX enzymes expression, PGE2 concentrations were elevated with age. Ovaries with tumor had elevated COX-1 expression and PGE2 concentration compared to normal ovaries. Our findings suggest that the up-regulation of COX enzymes with age is the main contributing factor in the age associated increase in PGE2. Furthermore, elevated PGE2 in ovaries of hens concomitant with age suggests its important role in early stages of ovarian carcinogenesis. The results demonstrated that there was a reduction in ovarian cancer severity and incidence in hens fed flaxseed diet. In correlation with decreased ovarian cancer severity and incidence, concentration of PGE2 and expression of COX-2 were diminished in ovaries of hens fed flaxseed. Our findings suggest that the lower levels of COX-2 and PGE2 are the main contributing factors in the chemo-suppressive role of long-term flaxseed consumption in ovarian cancer in laying hens. These findings may provide the basis for clinical trials of dietary intervention targeting prostaglandin biosynthesis for the prevention and treatment of ovarian cancer. Based on our previous findings, targeting COX expression and prostaglandin biosynthesis by dietary intervention using OM-3FAs and selective COX inhibitor can be an effective approach to prevent or suppress ovarian cancer. Thus, we conducted a series of studies to assess effect of fish oil, flax oil, Celecoxib, fish oil and Celecoxib combined or flax oil and Celecoxib combined on COX-1 and COX-2 expression, PGE2 concentrations, proliferation and apoptosis in normal and cancerous ovaries of laying hens. This study had not been performed in hens before, thus the first step was to find the optimum doses. In order to do so, we utilized one year old hens, divided them to groups of 6 hens, and fed them different doses of fish oil (50, 100, 175, 375 and 700 mg/kg), flax oil (100, 250, 500, 1000 and 1500 mg/kg) or Celecoxib (35, 65 and 100 mg/kg) for three weeks. The OM3-FAs andomega-6 fatty acids contents of egg yolks were determined by gas chromatography. Proliferation, apoptosis,COX-1, COX-2 and prostaglandin receptor subtype 4 (EP4) protein and mRNA expression and PGE2 concentration in ovaries were measured by PCNA, TUNEL, western blot, quantitative real-time qPCR and ELISA, respectively. The results indicated that 100 mg/kg fish oil was the most effective dose in reducing COX enzymes and PGE2, and increased apoptosis and reduced proliferation in ovaries. The lower doses of fish oil incorporated more OM-3FAs into yolks, reduced OM-6FAs and increased the egg laying frequency but did not affect EP4 expression. Unlike fish oil, the highest dose of flax oil (1500 mg/kg) caused the most significant reduction in COX expression and PGE2 concentration. Celecoxib was not perfectly selective in targeting COX-2, however, treating the hens with 65 mg/kg Celecoxib resulted in the most significant amelioration of PGE2 levels in ovaries. Using the optimum doses of fish oil, flax oil and Celecoxib, we aimed to investigate if these components can alter ovarian cancer end-points in normal and cancerous hen ovaries. There is an adverse relation between ovulation and health of ovaries. Thus, 3-4 year old hens were monitored for egg laying frequency and the hens with the least ovulation rate were selected for health assessment. The hens presenting poor health were scanned using ultrasound and if tumor mass and/or ascites were detected, they were chosen for this study. The hens with normal and cancerous ovaries were divided to groups and were fed fish oil, flax oil, Celecoxib, fish oil and Celecoxib combined, or flax oil and Celecoxib combined for 42 days. The results showed that fish oil and flax oil increased the incorporation of OM-3FAs into egg yolks in both normal and cancerous ovaries of hens. Fish oil reduced COX-1 and COX-2 in normal and cancerous ovaries. Fish oil, flax oil and Celecoxib reduced the COX-2 expression in ovaries. Combination of fish oil and Celecoxib and flax oil and Celecoxib decreased COX and PGE2 more than each of these treatments alone. The cancerous ovaries of hens treated with fish oil, flax oil, Celecoxib, and flax oil and Celecoxib combined increased the percentage of apoptotic cells compared to cancerous ovaries of control hens. The cancerous ovaries of hens treated with fish oil and Celecoxib had the highest number of apoptotic cells indicating that the combination of fish oil and Celecoxib is more effective than fish oil or Celecoxib alone. To our knowledge the present study provides the first insight into the efficacy of fish oil, flax oil, Celecoxib, alone or combined on the reduction of COX enzyme expression, PGE2 concentration and apoptosis in the normal and cancerous ovaries and further demonstrates the utility of the hen model for ovarian cancer. Our studies provided new insight into the potential mechanism of action of flaxseed, fish oil, flax oil and Celecoxib in the reduction of ovarian cancer and will establish the foundation for clinical trials to test the efficacy of dietary intervention for the prevention and suppression of ovarian cancer in women.
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Dietary factors affecting tissue profiles of long chain polyunsaturated fatty acids in cattleAlvarado-Gilis, Christian A. January 1900 (has links)
Doctor of Philosophy / Department of Animal Sciences and Industry / J. S. Drouillard / The main goal of this dissertation was to evaluate different methods to protect polyunsaturated fatty acids (PUFA) against biohydrogenation by ruminal microorganisms. The first chapter is a review of literature pertaining to fat and fatty acid metabolism by ruminants and why these fats are relevant in human nutrition. The second chapter discusses effects of supplementing high concentrations of dietary copper to feedlot cattle to assess impact on PUFA profiles in tissues. Two levels of copper (10 or 100 mg/kg) were supplemented to diets with or without flaxseed during the finishing period for beef heifers. Added copper did not affect performance (P > 0.15). Final body weights were similar for cattle fed with or without flaxseed (P > 0.05), but cattle fed diets with flaxseed consumed less feed (P < 0.05), and therefore were more efficient (P < 0.01). Carcass traits were unaffected by treatment. Feeding elevated levels of copper did not appreciably alter proportions of PUFA in plasma, but plasma concentrations of omega-3 fatty acids were greater for heifers fed flaxseed (P < 0.05). Chapter 3 describes the evaluation of 3 novel methods to protect PUFA from microbial biohydrogenation activity within the rumen, including a) coextrusion of flaxseed with molasses; b) mixing with soybean meal followed by induction of a non-enzymatic browning reaction; and c) encapsulation of ground flaxseed within a matrix consisting of dolomitic lime hydrate (L-Flaxseed). The resulting products were evaluated using in vitro methods to estimate resistance to biohydrogenation or in 12- to 14-d feeding studies in which plasma concentrations of [alpha]-linolenic acid (ALA) were measured. Our processing strategies a) and b) did not improve efficiency of omega-3 fatty acid utilization (P > 0.1). The in situ study of L-flaxseed revealed a 2-fold increase in resistance of ALA to ruminal biohydrogenation, and the concentration in plasma after 14 d on feed was more than 4 times that observed in cattle fed ground flaxseed, suggesting the dolomitic lime hydrate
was effective as a protective matrix. Chapter 4 evaluated performance, carcass traits, and meat quality of finishing beef heifers in response to feeding diets containing L-Flaxseed. Animals were blocked by weight, randomly assigned to individual pens, and pens to 6 dietary treatments: Control (high concentrate finishing diet), ground flaxseed fed at 3 or 6% of diet DM, L-Flaxseed fed at 2, 4, or 6%. Concentration of ALA in meat increased linearly in response to the level of flaxseed fed (P < 0.05); Moreover, transfer of dietary ALA to tissues increased by 47% when flaxseed was encapsulated within the dolomitic lime matrix. Cattle that were fed diets with 4 or 6% L-Flaxseed consumed less feed than other treatments (P < 0.05), which adversely affected feedlot performance and carcass traits.
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