FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Este estudo teve como objetivo determinar a composiÃÃo centesimal, o perfil de Ãcidos graxos e o valor calÃrico de trÃs espÃcies de crustÃceos do Estado do CearÃ. As espÃcies estudadas sÃo as mais comercializadas: lagosta espinhosa (Panulirus argus), camarÃo branco (Litopenaeus vannamei), caranguejo uÃÃ, (Ucides cordatus).Os resultados obtidos demonstraram elevados teores de umidade na vÃscera de caranguejo. As carnes de lagosta e de caranguejo apresentaram os maiores percentuais de proteÃna. Os teores de lipÃdios totais foram maiores no hepatopÃncreas de lagosta.Quanto Ãs cinzas, os maiores valores foram detectados na cabeÃa de camarÃo e na carne de caranguejo. O maior valor calÃrico foi encontrado no hepatopÃncreas de lagosta. Na carne e hepatopÃncreas de lagosta destacaram-se os Ãcidos graxos: palmÃtico, esteÃrico, olÃico. Na fraÃÃo de lipÃdios neutros de cabeÃa de camarÃo, os quatros Ãcidos graxos majoritÃrios foram linolÃico, palmÃtico, olÃico e DHA. Nos fosfolipÃdios dessa amostra, os Ãcidos palmÃtico, linolÃico, olÃico e esteÃrico foram os majoritÃrios. / This study aimed to determine the chemical composition, the profile fatty acids and caloric value of three species of crustaceans of the State of CearÃ. The species are the most commercialized, spiny lobster (Panulirus argus), white shrimp (Litopenaeus vannamei), crab uÃÃ (Ucides cordatus). The results showed high levels of moisture in Crab viscera. The meat of lobster and crab presented higher percentages of protein. The levels of total lipids were higher in lagosta.Quanto hepatopancreas of the ash, the highest values ​​were detected the head of shrimp and crab meat. The caloric value was greater found in the hepatopancreas of lobster. In meat and lobster hepatopancreas highlights are the fatty acids: palmitic, stearic, oleic. In the fraction of lipids neutral shrimp head, the four major fatty acids were linoleic, palmitic, oleic and DHA. Phospholipids in this sample, the fatty palmitic, linoleic, oleic and stearic acids were the major ones.

O objetivo deste estudo foi avaliar o efeito da competição de triathlon na função e morte de neutrófilos de atletas de elite e investigar o possível envolvimento dos ácidos graxos livres (AGs) neste processo. Os neutrófilos foram obtidos do sangue coletado de 11 sedentários e de 12 triatletas em repouso e após competição de triathlon (Half Ironman, 2 Km de natação, 80 Km de ciclismo e 20 Km de corrida). A competição de triathlon aumentou a capacidade dos neutrófilos de migrar e de realizar burst oxidativo, porém inibiu a fagociose realizada por estas células. Além disso, induziu aumento da fragmentação de DNA e externalização de fosfatidilserina. A competição de triathlon aumentou a concentração de AGs no plasma dos triatletas e esta foi correlacionada positivamente com a proporção de neutrófilos com DNA fragmentado e fosfatidilserina externalizada. A elevação da concentração plasmática dos ácidos oléico, linoléico e esteárico induzida pela competição parece estar envolvida nas alterações funcionais e na apoptose verificadas após a competição de triathlon. / The objective of this study was to evaluate the effect of triathlon competition on function and death of neutrophils from elite athletes and to investigate the involvement of fatty acids in this process. Neutrophils were obtained from blood collected from eleven sedentary volunteers and twelve triathletes under rest and after a Half Ironman triathlon competition (2 Km swimming, 80 Km cycling and 20 Km running). The triathlon competition increased the migration and reactive oxygen species production in neutrophils, however it reduced the phagocytosis activity. Moreover, it induced neutrophils death possibly by apoptosis as indicated by DNA fragmentation and phosphatidylserine externalization. The increase in plasma levels of oleic, linoleic and stearic acids induced by the competition may be involved in modulation on neutrophil function and death.

Introdução: Evidências experimentais, epidemiológicas e clínicas mostram o papel da inflamação na patogênese de desordens metabólicas, sendo a modulação da resposta inflamatória associada a quantidade e a qualidade dos ácidos graxos (AG) da dieta. Polimorfismos de nucleotídeo único (SNP) podem influenciar a relação entre AG e concentração plasmática de biomarcadores inflamatórios. Objetivo: Verificar a associação de SNP relacionados aos genes da adiponectina, Receptor do tipo Toll (TLR)-4, interleucina (IL)-1 e IL-6 e ingestão de lipídios com um padrão inflamatório sistêmico, baseado na concentração plasmática de onze biomarcadores inflamatórios em estudo de base populacional ISA-Capital. Metodologia: O presente estudo compreende adultos (20 a 59 anos) do estudo de base populacional, ISA-capital 2008-2010 (n=302). A coleta dos dados dietéticos foi realizada por meio de recordatório de 24 horas, aplicado em duplicata. A partir do plasma, foram determinadas as concentrações plasmáticas de adiponectina, proteína C reativa (PCR), IL-1, IL-6, IL-8, IL-10, fator de necrose tumoral-alfa, IL- 12p70, Quimiocina C-C motif ligante (CCL) 2, molécula de adesão intercelular solúvel (sICAM)-1 e molécula de adesão celular vascular solúvel (sVCAM)-1, por meio da técnica multiplex de imunoensaio, e o perfil de ácidos graxos (AG) do plasma por cromatografia gasosa. A partir do DNA genômico foi realizada a genotipagem dos SNP relacionados aos genes da adiponectina (rs266729, rs17300539, rs16861209, rs1501299 e rs2241766), TLR4 (rs4986790, rs4686791, rs5030728, rs11536889), IL-1 (rs1143623, rs16944, rs1143627, rs1143634 e rs1143643) e da IL-6 (rs1800795, rs1800796, rs1800797) pelo sistema Taqman Open Array. Uma análise multivariada de Cluster (k-means) foi realizada para separar os indivíduos legíveis entre grupo inflamado (INF), n=93, e grupo não inflamado (NINF),n=169, segundo a concentração plasmática dos onze 8 biomarcadores inflamatórios avaliados. Resultados: Todos os SNP estavam em equilíbrio de Hardy-Wienberg (n=301). O INF apresentou idade, circunferência da cintura, pressão arterial e concentrações de triacilgliceróis sanguíneo estatisticamente maiores que aqueles observados para o NINF. O INF apresentou concentração plasmática de AG palmítico (C16:0), razões AG saturados (AGS)/AG ômega-6 (n-6) e AGS/ AG poli-insaturados (AGPI) e atividade estimada da enzima estearoil CoA desaturase aumentadas e concentrações plasmática de AGPI, n-6 e AG araquidônico (AA) e atividade estimada da enzima delta-5-dessaturase (D5D) reduzidas em comparação com o NINF. Interações SNP-AG plasmáticos estatisticamente significantes para predisposição ao padrão inflamatório sistêmico foram detectadas entre o SNP +6054 G>A (rs1143643) do gene da IL-1 e os AG esteárico, AA e AGPI e atividade estimada da enzima delta-6-desaturase (D6D); entre o SNP +3725 G>C (rs11536889) do gene do TLR-4 e a razão AA/AG eicosapentaenoico (EPA); entre o SNP +45 T>G (rs2241766) do gene da adiponectina e o AG ômega-3 (n-3); entre o SNP -7734 C>A (rs16861209) do gene da adiponectina e AA; e entre o SNP -11391 G>A (rs17300539) do gene da adiponectina e AGS. Conclui-se que algumas frações dos AG do plasma podem modular a inflamação e que SNP localizados nos genes da adiponectina, TLR-4, IL- 1 e IL-6 podem interagir com as frações de AG do plasma influenciando a chance de desenvolver uma inflamação sistêmica. / Introduction: Experimental, epidemiological and clinical evidences point to a pathogenic role of inflammation on metabolic disorders development, and to the relationship between this inflammatory response and the quantity and quality of dietary fatty acids. Single Nucleotide Polymorphisms (SNP) can modulate the relationship between fatty acids and plasma inflammatory biomarkers levels. Objective: To verify the association between SNP in the genes of adiponectin, TLR- 4, IL-1 and IL-6 and dietary fatty acids and their effects to a systemic inflammatory pattern at a population-based study ISA-Capital. Methods: This study sample was composed by adults (20 to 59 years), participants of the population-based study ISAcapital 2008-2010 (n=302). Dietary data was collected using two 24 hours dietary recall. Plasma concentration of adiponectin, C reactive protein, IL-1, IL-6, IL-8, IL- 10, tumor necrosis factor-alfa, IL-12p70, Chemokine C-C motif ligand (CCL) 2, soluble intercellular adhesion molecule (sICAM)-1 and soluble vascular cell adhesion molecule (sVCAM)-1 was determined by multiplex immunoassay. Plasma FA profile was determined by gas chromatography. SNP from adiponectin (rs266729, rs17300539, rs16861209, rs1501299 e rs2241766), TLR4 (rs4986790, rs4686791, rs5030728, rs11536889), IL-1 (rs1143623, rs16944, rs1143627, rs1143634 e rs1143643) and IL-6 (rs1800795, rs1800796, rs1800797) gene were genotyped by Taqman Open Array system. A Cluster multivariate analysis (k-means) was conducted to separate individual into inflammatory group (INF), n=93, and noninflammatory group (NINF), n=169, according to eleven inflammatory biomarkers plasma levels. Results: All the SNP were in Hardy-Weinberg equilibrium (n=301). INF had statistically higher age, waist circumference, blood pressure and plasma tryglicerides concentration than NINF. INF presented statistically higher plasma palmitic acid (C16:0) levels, saturated fatty acid (SFA)/omega-6 fatty acid (n-6) ratio and SFA/polyunsaturated fatty acid (PUFA) ratio and estimated stearoil CoA 10 desaturase activity, and statistically lower plasma PUFA, n-6 and arachidonic acid e (AA) and estimate delta-5-desaturase (D5D) activity in comparison to NINF. Statistically significant SNP-plasma fatty acid interactions were found between SNP +6054 G>A (rs1143643) of IL-1 gene and stearic acid, AA and PUFA and estimate delta-6-desaturase (D6D) activity; between SNP +3725 G>C (rs11536889) of TLR-4 gene and AA/eicosapentaenoic acid (EPA) ratio; between SNP +45 T>G (rs2241766) of adiponectin gene and omega-3 fatty acid (n-3); between SNP -7734 C>A (rs16861209) of adiponectin gene and AA; and between SNP -11391 G>A (rs17300539) of adiponectin gene and SFA. In conclusion, some plasma fatty acid subfractions can modulate inflammation and SNP of adiponectin, TLR-4, IL-1 and IL-6 genes can interact with plasma fatty acids to modulate the chance to develop systemic inflammation.

Orientadores: Maria Regina Wolf Maciel, Cesar Benedito Batistella / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-04T03:08:23Z (GMT). No. of bitstreams: 1 Martins_PatriciaFazzio_M.pdf: 4266626 bytes, checksum: a048f065c12ba7c99e232ca5dd0eb892 (MD5) Previous issue date: 2005 / Resumo: Os destiladores desodorizados de óleos vegetais (DDOV) são constituídos por diversas substâncias, entre elas, os ácidos graxos livres, fitoesteróis, tocoferóis, ésteres de fitoesteróis, hidrocarbonetos, glicerídeos e produtos da decomposição destas moléculas. O teor de ácidos graxos livres (AGL) nos DDOV varia entre 24 e 85%. Devido ao seu alto teor, a separação dos AGL dos destilados desodorizados dos óleos vegetais é uma etapa importante para proceder à concentração de tocoferóis e fitoesteróis em alta pureza. Os tocoferóis são substâncias naturais valiosas usadas em alimentos, cosméticos e fármacos devido às suas propriedades vitamínicas e antioxidantes. Os fitoesteróis têm recebido grande atenção ultimamente, devido à sua atividade anticolerolêmica e potencialidade de aplicação em nutracêuticos. Neste trabalho, foram realizados ensaios para estudar a remoção dos AGL presentes nos destilados desodorizados de óleos vegetais provenientes do refino de óleo de girassol (DDOG) e de canola (DDOC), utilizando o processo de destilação molecular. Para isso, diversas condições operacionais de temperatura do evaporador e da vazão de alimentação foram utilizadas. O objetivo é avaliar o comportamento do sistema e determinar as melhores condições operacionais para realizar a eliminação de ácidos graxos, minimizando as perdas de tocoferóis durante o processo... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Distilates of the vegetable oil deodorization (DVOD) are composed by free fatty acids, phytosterols, tocopherols, phytosterol esters, hydrocarbons, acylglycerols and products of decomposition of these molecules. The content of free fatty acids (FFA) in the deodorizer distillates varies between 24% and 85%. Due to its high content, free fatty acid separation from deodorizer distillate is an important step to concentrate tocopherols and phytosterols in high purity. Tocopherols are valuable natural substances used in food, cosmetic and pharmaceutical industries due to its vitaminic and antioxidant properties. Phytosterols have received grat attention because its hipocholesterolemic properties and potential to be used in nutraceutics. In this work, separation of free fatty acids from sunflower (SuODD) and canola oil (CODD) deodorizer distillates was investigated through molecular distillation. For this, different operating conditions of evaporator temperature and feed flow rate were used. The intention is to evaluate the behavior of the system and to determine the best operating conditions to eliminate FFA, minimizing tocopherol losses during the process. Furthermore, in this work, it was necessary to establish analytical techniques to determine the contents of tocopherols, phytosterols, triacylglycerols, diacylglycerols, monoacylglycerols and free fatty acids in DVOD. Besides, of DDOC and DDOG, the soybean oil deodorizer distillate (SODD) was also characterized... Note: The complete abstract is available with the full electronic digital thesis or dissertations / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química

1. The literature has been reviewed with respect to the dietary intake and subsequent metabolism of polyunsaturated fatty acids (PUFA), of both the n-6 and n-3 series, in teleost fish. Particular emphasis has been made to the physiological roles of PUFA with respect to cell membrane function and eicosanoid production. 2. Atlantic salmon post-smolts were fed practical-type diets, based on fish meal, in three separate dietary experiments of 10-16 weeks duration. The first trial compared dietary lipid supplied either as fish oil (FO) or as sunflower oil (SO) with the diets having an n-3/n-6 PUFA ratio of 9.4 and 0.2 respectively. The second trial used diets formulated with blends of FO, SO, grape seed oil and safflower oil to provide linoleic acid at 10, 25 and 45% of total dietary fatty acids. The third trial was similar to the first but with an additional diet in which the lipid component was supplied by linseed oil (LO). All diets satisfied the nutritional requirements of salmonid fish for n-3 PUFA. There were no statistically significant differences in final weights between dietary treatments in the third trial. However, in the second trial fish fed the intermediate level of linoleic acid (25%) attained a significantly higher final weight compared to both other treatments while fish fed the highest level of linoleic acid (45%) had significantly lower final weights compared to both other treatments. In the first trial the effect of diet on growth (weight gain) could not be ascertained as the initial weights of the fish were significantly different. 3. A number of fish fed SO developed severe cardiac lesions which caused thinning of the ventricular wall and heart muscle necrosis. In addition the fish fed diets containing SO were susceptible to a transportation-induced shock syndrome that resulted in 30% mortality. 4. Incorporation of linoleic acid (18:2n-6) into membrane phospholipids increased in response to dietary intake with fish fed SO having increased levels of 18:2n-6 (up to 15-fold), 20:2n-6 (up to 12-fold), 20:3n-6 (up to 25-fold) and arachidonic acid (AA; 20:4n-6) (up to 3-fold), and decreased levels of eicosapentaenoic acid (EPA; 20:5n-3) (up to 3-fold). The ratio of n-3/n-6 PUFA was decreased (up to 4-fold) and the20:4n-6/20:5n-3 ratio increased (up to 9-fold) in membrane phospholipids from fish fed SO compared to those fed fish oil. While the tissue phospholipids from fish fed La had increased levels of 18:2n-6, 20:2n-6 and 20:3n-6, the levels of AA, 22:4n-6 and 22:5n-6 were similar to or significantly reduced compared to fish fed FO. Membrane phospholipids from fish fed LO also had increased 18:3n-3 and 20:4n-3 compared to both other treatments while in some tissues and phospholipid classes EPA was increased compared to fish fed FO. 5. These dietary induced changes in phospholipid eicosanoid precursor ratio were reflected in altered eicosanoid production. In gill cells, stimulated with the calcium ionophore A23187, 12-hydroxy-8, 10, 14, 17-eicosapentaenoic acid (12-HEPE) was the major 12-lipoxygenase product in fish fed Fa. In stimulated gill cells from fish fed SO and LO, 12-HEPE, 12-hydroxy-5, 8, 10, 14-eicosatetraenoic acid (12-HETE), 14- hydroxy-4, 7, 10, 13, 16, 19-docosahexaenoic acid (14-HDHE) and thromboxane B2 (TXB2) were all decreased compared to fish fed FO. However, the ratio of 12- HETE/12-HEPE was significantly elevated in stimulated gill cells from SO-fed fish compared to both other treatments. In stimulated blood leucocytes leukotriene B4 (LTB4)' 12-HETE and TXB2 were significantly increased while LTB5 and 12-HEPE were significantly decreased in fish fed SO compared to those fed FO. Blood leucocytes from fish fed LO produced less TXB2 compared to fish fed SO and prostaglandin E2 was reduced compared to both other treatments. In isolated cardiac myocytes stimulated with A23187, TXB2 production was increased in SO fed fish compared to those fed FO. 6. The activity of cardiac sarcoplasmic reticulum Ca2+-Mg2+ATPase was not affected by dietary treatment. 7. An established cell line derived from chum salmon heart (CHH-1) was utilised to study PUFA metabolism. The CHH-1 cells exhibited considerable A6 desaturase activity but showed no preference towards n-3 over n-6 PUFA. CHH-1 cells did exhibit significant A5 desaturase activity which showed a preference towards n-3 PUFA. No A4 desaturation activity was observed. Elongation of C20 PUFA was especially active in CHH-1 cells with C22 PUFA being specifically incorporated into phosphatidylethanolamine (PE) and phosphatidylserine (PS). CHH-1 cells supplemented with 20:3n-6 showed reduced growth rate, cell death and unusual pycnotic appearance, compared to those supplemented with other PUFA. 8. The lipid compositions of hearts and livers from wild and farmed parr and presmolts were analysed and compared. The fatty acid compositions of triacylglycerols (TAG) and phospholipids from both farmed parr and pre-smolts contained greater amounts of monoenoic fatty acids compared to their wild counterparts. TAG, phosphatidylcholine (PC) and PE from heart and liver of wild fish contained more 18:2n-6 and AA compared to farmed fish. Linolenic acid, EPA and 22:Sn-3 were increased in hearts and livers of wild fish compared to farmed. Docosahexaenoic acid (DHA; 22:6n-3) levels were higher in heart and liver of farmed fish, particularly in heart PC, PS and TAG. The n-3/n-6 PUFA ratio was generally lower in wild compared to farmed fish, largely due to higher n-6 PUFA, in particular AA, in wild fish. 9. The results are discussed with respect to the competitive interactions between PUFA of the n-6 and n-3 series which determine the fatty acid compositions of membrane phospholipids in salmon. The ratio of n-3/n-6 PUFA in membrane phospholipids, and in particular the ratio of AAIEPA, appears important in terms of membrane physiology and biochemistry, eicosanoid production and the development of cardiac histopathological lesions.

Magister Scientiae - MSc / Several abnormal conditions, including some cancers, have been associated with changes in the membrane lipid and FA composition. Dietary fat serves as a major source of lipids and FA, particularly the polyunsaturated fatty acids (PUFA), n-6 and n-3. High intakes of n-6 PUFA have been linked to the development of colon cancer in association with low n-3 PUFA intake. Therefore understanding the differences in the lipid and FA profiles between cancer and normal cells in the colon, and the role diet plays in these factors may be invaluable in understanding their role in carcinogenesis. This study compares the lipid profile of azoxymethane (AOM) induced colon polyps to that of the surrounding mucosa tissue in rats fed a diet high in n-6 PUFA. Male Fischer rats were fed the AIN-76A diet containing sunflower oil that has high n-6 PUFA content for a period of nine months. Results indicate that the lipid and FA content of the colon polyps differs significantly from the surrounding mucosa. Colon polyps had an increase in membrane phopholipids phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Changes in membrane fluidity were indicated by the decrease (0.05) in the PC/PE and cholesterol/phospholipids (chol/PL) ratios, and increase (0.05) in the polyunsaturated FA/saturated FA (P/S) ratio. Metabolism of FA was significantly altered in the polyps favouring n-6 FA metabolism and the production of prostaglandin E2. No clear indication of impaired & Delta;6-desauturase enzyme activity was noticed. Increases in the n-6 PUFA content could be a reflection of the dietary FA intake that increases FA incorporation in the polyps. Changes in the FA parameters of the polyps, particularly an increase in C20:4n-6 and the n6/n3 ratio have been shown to contribute to the rapid growth of cancer tissue. These lipid changes associated with the development of colon polyps could provide unique targets for developing strategies in chemoprevention by dietary manipulation. / South Africa

Aquaculture feeds, traditionally composed mainly of fishmeal and fish oil, currently represent the largest cost to fish farmers. With aquaculture growing at an average of 8.8% per year and limited supply of fishmeal and fish oil, suitable alternatives must be found. In addition to increasing sustainability and lowering production costs, the use of plant and/or animal ingredients has the potential to lower flesh levels of persistent organic pollutants (POPs) such as polychlorinated biphenyls. Fish oil and to a lesser extent fishmeal, are considered to be the largest source POPs in farmed fish. Using alternative feed ingredients however, can compromise fish growth and the flesh quality of the final product. Lipid sources including flaxseed oil, canola oil, poultry fat and the protein sources canola protein concentrate, soy protein concentrate and poultry by-product meal were examined as alternatives to fish oil and fishmeal in one on-farm field study and one laboratory feeding trial with Atlantic salmon (Salmon salar) and two laboratory feeding trials conducted on sablefish (Anoplopoma fimbria), a relatively new marine aquaculture species. The nutritive value of the alternative ingredients was assessed on the basis of fish growth performance, proximate composition, fatty acid composition and apparent digestibility coefficients. Sensory attributes were evaluated in the sablefish studies while flesh POP levels were determined in both species. The use of alternative dietary lipids showed no negative effects on fish performance. However replacement of fishmeal with plant proteins in some cases, negatively affected fish growth. Flesh levels of persistent organic pollutants were significantly decreased (p<0.05) with the use of alternative dietary lipids, and flesh levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were also depressed. Activated carbon treated anchovy oil and finishing diets were examined in the Atlantic salmon laboratory feeding trial and were effective at lowering flesh POP levels while providing high levels of EPA and DHA. The use of alternative feed ingredients will soon be inevitable in aquaculture feeds. The current research shows alternative lipids and proteins can be incorporated successfully in sablefish and Atlantic salmon feeds with minimal effects on fish growth and quality. / Land and Food Systems, Faculty of / Graduate

The objective of the study was to determine growth performance, physico-chemical attributes, oxidative stability and sensory quality of pork from pigs fed one of three dietary treatments, eac containing 0%, 2.5% or 5% (T1, T2 and T3, respectively) Moringa oleifera leaf meal (MOLM). Dietary treatments were formulated to be isonitrogenous and isoenergetic for weaner (6 – 8 weeks) and grower (9 – 13 weeks) phases. Twelve Large White (LW) and 12 Kolbroek (KB) male pigs at 6 weeks of age, initially weighing an average 10 kg, were randomly allocated to one of the dietary treatments, each with four replicates, in individual pens. Feed and water were offered ad libitum. The Longissimus thoracis et lumborum (LTL) muscle of each carcass (n = 24) was sampled for meat quality and fatty acid analyses. Breed differences in measured parameters were observed. In pigs receiving 5% MOLM, the LW had significantly the highest ADFI (P<0.05) than KB pigs. In pigs receiving 2.5% and 5% MOLM, backfat thickness was significantly highest (P<0.05) compared to those receiving 0% MOML. Dietary inclusion of MOLM had no significant effects (P>0.05) on the physico-chemical quality of pork from LW pigs; although it significantly (P<0.05) increased a* and reduced WBSF values in pork from KB pigs. Pork from LW pigs receiving 5% MOLM had significantly increased (P<0.05) n-3 content of the subcutaneous tissue of LW pigs compared to KB, and also when compread to other treatment groups. In both breeds, the composition of PUFA: SFA and n-6: n-3 in the subcutaneous adipose tissue was significantly (P<0.05) lower in T2 and T3 than in T1. The n-3 levels for pork muscle from LW pigs receiving 2.5% and 5% MOLM, and from KB pigs receiving 5% MOLM, were significantly (P<0.05) lower. Inclusions of MOLM significantly (P<0.05) reduced the n-6: n-3 fatty acids in pork from both LW pigs and KB pigs. Consumer scores on sensory attributes (aroma intensity, initial impression of juiciness, first bite, sustained impression of juiciness, muscle fibre and overall tenderness and overall flavor intensity) significantly (P<0.05) increased as the level of MOLM inclusion in the diet increased; and higher scores were observed in fried meat than in boiled for most sensory attributes. It may be concluded that inclusion of MOLM in pig diets up to 5% improved the ADFI, a*, tenderness of pork without adversely affecting the FCR and other physico-chemical quality attributes; and resulted in desired increase in levels of n-3 and reduced the n-6: n-3 fatty acid ratio.

Heat exposure causes several physiological and metabolic alterations. Although lipids are vital in sustaining energy production, heat-induced alterations in lipid metabolism have not been clearly established. CHAPTER 1 reviews the known metabolic alterations resulting from heat stress, with a specific focus on changes in whole-body lipid utilization and plasma lipids. CHAPTER 1also outlines the physiological changes caused by heat stress, and their role in reducing exercise performance. The study presented in CHAPTER 2 has shown that, compared to thermoneutral conditions, NEFA concentrations were 37% higher following passive heating and 34% higher following exercise in the heat, without significant changes in whole-body lipid utilization. In addition, the level of hyperthermia attained during passive pre-heating and exercise in the heat resulted in a 13% decrease in total external work and a significantly higher rate of perceived exertion. CHAPTER 3 summarizes the study results and presents the limitations and applications of the study.

Ultraviolet radiation (UVR) is a complete carcinogen, inducing skin cancer via DNA photodamage that can lead to mutagenesis, and promoting its growth via photoimmunosuppression (PI). The omega-3 polyunsaturated fatty acid (n-3 PUFA) eicosapentaenoic acid was shown in murine studies to protect against PI and UV-induced skin cancer although the mechanism is uncertain. The principal objectives of this thesis were to (i) examine whether n-3 PUFA can protect against a clinical model of PI in healthy humans and (ii) explore whether the underlying mechanism could be abrogation of UV-induced depletion of antigen-presenting Langerhans cells (LC) from the epidermis, and/or impact on immunomodulatory cytokines. Nickel (Ni) allergic females (n=79) were randomized to 3 months of daily supplementation with 5g n-3 PUFA (70% eicosapentaenoic acid, EPA; 10% docosahexaenoic acid, DHA) or the placebo medium chain triglyceride, GTCC. Local PI was clinically assessed post supplementation using the nickel contact hypersensitivity (Ni CHS) model. In each volunteer, Ni patches were applied to 3 skin sites that were irradiated for 3 consecutive days with UV-doses of 1.89, 3.82 & 7.59J/cm2 respectively. CHS responses were measured and compared to responses of control patches applied on unirradiated skin using a reflectance erythema meter. In the same subjects, assessments of cellular and biochemical mediators of PI were made pre and post supplementation. At 24hr post irradiation with an erythemal UV-dose (4 minimal erythemal doses) to upper buttock skin, half the subjects (n=39) had skin punch biopsies taken and the other half (n=40) had suction blisters raised on this irradiated skin and on unirradiated skin of the contralateral buttock. Epidermal sheets were prepared from the punch biopsies and immunohistochemically stained to assess UV-induced LC numbers. Levels of immunomodulatory cytokines were analysed in the suction blister fluid using Luminex multiplex assay kits. To evaluate compliance and bioavailability, blood samples were taken from all volunteers, pre and post supplementation and EPA% weight in red blood cell membranes was examined using gas chromatography. Post supplementation, EPA %wt was significantly higher in the active group compared to control: mean 3.61% ± 0.22% (SEM) vs. 0.93% ± 0.06% (p<0.001). 3 volunteers showed evidence of non-compliance and were excluded from further analysis. Compared to placebo, evidence for protection against local PI of Ni CHS was apparent post n-3 PUFA at all UV doses, reaching statistical significance at the UV-dose of 3.8J/cm2 (p<0.05). No significant difference in post-UV epidermal LC numbers after supplementation was seen between active and placebo groups, with a % fall following UV of 76.61 ± 3.39% (SEM) in the active group and 73.52 ± 5.24% (SEM) in the control group. When intragroup comparisons were made pre vs. post supplementation, a similar increase in UV-induced LC depletion from the epidermis was seen in both groups, reaching statistical significance following n-3 PUFA (p=0.018). Levels of interleukins IL-10 and IL-8, and of TNF-α, increased post-UVR in both active and control groups pre-supplementation, with no changes occurring following supplementation. In conclusion, supplemental EPA was bioavailable and evidence of protection against clinical PI of Ni CHS was seen in the actively treated group. However, no evidence was found that this abrogation of PI was mediated through a reduced effect of UV on migration of epidermal LC or the immunomodulatory cytokines examined. This original study gives the first evidence that dietary n-3 PUFA may protect against clinical PI, and potentially skin cancer promotion, in humans. Further research is needed to confirm this finding, and to examine the underlying mechanisms, which could involve other immunoregulatory cells of the skin, such as dermal dendritic cells and T regulatory cells and other mediators of UV-immunosuppression including the prostanoids, which may be modified by n-3 PUFA.