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Levy, Milne Ryna. "Differential metabolism of eicosapentaenoic acid and docosahexaenoic acid." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ56664.pdf.
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Price, Sarah A. "The role of eicosapentaenoic acid in cancer cachexia." Thesis, Aston University, 1997. http://publications.aston.ac.uk/10968/.
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Cachexia is a wasting syndrome often associated with malignancy, characterised by alterations in host metabolism and significant catabolism of host adipose tissue and skeletal muscle. The MAC16 murine adenocarcinoma is profoundly cachexigenic, inducing host weight-loss at relatively small tumour burden without the induction of anorexia. A 4DkDa factor capable of inducing lipolysis in vitro via an activation of adenylate cyclase (AC) has been isolated from the MAC16 tumour, and the urine of cachectic cancer patients, using a series of ion exchange and gel exclusion chromatography procedures. This lipid-mobilising factor (LMF) has been demonstrated to stimulate lipolysis in adipocytes dose-dependently via a signal transduction pathway involving, possibly, β3-adrenoceptors. Oral administration of the n-3 polyunsaturated fatty acid (PUFA) eicosapentaenoic acid (EPA) attenuated the progression of cachexia, but not the production of LMF, in MAC16 tumour-bearing mice, and was significantly incorporated into plasma phospholipids, skeletal muscle and adipose tissue. EPA supplemented cancer patients also demonstrated significantly increased plasma EPA concentrations. Decreased plasma membrane AC activity in response to LMF was observed in adipocytes isolated from mice receiving EPA. Incubation in vitro of adipocytes, or plasma membranes, with PUFAs significantly altered membrane fatty acid composition and attenuated the induction of both lipolysis, and AC activity, by LMF. The inhibitory actions of EPA, but not docosahexaenoic acid, are probably the consequence of an interaction with guanine nucleotide binding proteins (G-proteins). Progression of the cachectic state induced an up-regulation of adipocyte membrane expression of stimulatory G-proteins, allied with a concomitant down-regulation of inhibitory G-proteins, thus facilitating the catabolic actions of LMF, implying some tumour-mediated effect. A reversal of such alterations was observed upon oral administration of EPA, suggesting that the primary mechanism of action of this fatty acid is an inhibition of the end organ effects of LMF.
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Gu, Wenjia. "Scaling up photoautotrophic production of eicosapentaenoic acid (EPA) using microalgae." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/30065.
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Food insecurity is one of the major challenges that the world faces today. Improving food security is about not only ending hunger but also ensuring easy, affordable access to nutritious, healthy food for all people. The importance of adequate consumption of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is well recognized. EPA and DHA are essential omega-3 fatty acids that must obtained from the diet. Producing sufficient amounts of EPA and DHA to meet the global demand from their conventional sources – fish – is becoming increasingly challenging due to population growth and overfishing. To bridge the supply gap of EPA and DHA via sustainable means, the idea of sourcing these nutrients directly from their natural primary producers – microalgae – has emerged.
The overarching aim of this thesis was to develop a scalable bioprocess that used photoautotrophic microalgae to produce EPA. Such a strategy would offer the advantages of not requiring arable land or potable water, thus would avoid competition with existing food production techniques for these resources. Currently, commercial production of microalgal EPA is hindered by the process economics. One of the major hurdles is the difficulties of growing EPA-producing microalgae efficiently at large scales, hence the development of scalable, cost-effective production processes is needed. In this research, three broad avenues were taken: (1) identification of suitable strains, (2) optimization of the process operation and (3) optimization of the bioreactor design.
Microorganisms used for industrial applications need to have certain characteristics. A key metric is high product accumulation under realistic settings, others include robust growth and consistent performance in industrial systems as well as tolerance to changes in the growth conditions. Systematic evaluations using these industrial metrics have not been done for screening EPA-producing microalgae. To address this gap, a screening procedure was conducted to quantify the EPA productivity for a range of microalgae in both 300 mL flask and 5 L flat-panel photobioreactor cultures. It was found that results from the flask screening offered poor predictions of performance in photobioreactors, suggesting a need for improved screening tools, such as scale-down simulators, for selecting industrial microalgal species. In the photobioreactor cultures Phaeodactylum tricornutum displayed the highest EPA productivity, which was approximately an order of magnitude higher than those of the other species tested. The results demonstrated the potential of P. tricornutum for large scale production of EPA.
To further evaluate the suitability of P. tricornutum for scaled-up production, the effects of two key environmental factors, temperature and salinity, on the EPA production of P. tricornutum were examined in photobioreactors. It was found that P. tricornutum could tolerate relatively wide ranges of temperature (13-27 °C) and salinity (35-50 g L-1); within these ranges its EPA content was approximately constant at 5% of the dry biomass weight. These results illustrate the robustness of P. tricornutum which is an obvious advantage from the perspective of industrial production. A comprehensive nutritional analysis was also performed for the biomass of P. tricornutum. In addition to being a good source of EPA, P. tricornutum biomass was also rich in protein (45% of dry weight), iron and vitamin B12. The nutritional information here could serve as a starting point for the formulation of P. tricornutum into food products.
With P. tricornutum being identified as a suitable species, improving the EPA productivity was the next step in the process development. The use of reliable computational models could greatly facilitate the identification of optimal operating strategies, with fewer laborious, time-consuming experiments required. This research demonstrated the development of a model for the EPA production of P. tricornutum, which was the first to predict the biomass and EPA productivities along with the EPA concentrations in the biomass and fatty acid fraction for microalgae.
The model was built on a kinetic modelling framework where the system behaviour was simulated using a set of ordinary differential equations, with the integrated effect of light and nitrogen availability being accounted for. This mathematically simple model was able to produce satisfactory predictions for different reactor geometries and scales (5 L flat-panel and 50 L cylindrical reactors), light path lengths (5 cm and 19 cm) as well as operating modes (batch and repeated-batch), with the model-data mismatches being typically less than 20%. Using this model, an optimized repeated-batch strategy was developed. Implementation of this strategy over four repeated cycles led to 50% and 20% increases in the biomass and EPA productivities, respectively. The results demonstrated the usefulness of this model as a tool in the scale-up, design and optimization of microalgal EPA production.
Another avenue for improving process productivity is developing better reactor designs. A major challenge in improving the performance of photoautotrophic cultures is delivering light into high-cell-density cultures. Using Computational Fluid Dynamics (CFD) with Lagrangian particle tracking, this work examined means of improving the frequency at which the microalgal cells were transported between the light and dark zones, something that was recognized as a way for improving light delivery but has not been sufficiently evaluated under industrially relevant conditions. Different superficial gas velocities (0.6-6.0 cm s-1), reactor diameters (0.14-0.29 m), internal structure designs (split-cylinder airlift, segmental baffles, disc-and-doughnut baffles) and sparger configurations (asymmetrical and oscillatory spargers) were investigated for their effect on the hydrodynamics in 50 L bubble column photobioreactors. It was found that the frequency increased linearly with the superficial gas velocities but did not vary appreciably with the reactor diameter within the tested range. The frequency could be increased by 160% and 50% by the installation of segmental baffles and disc-and-doughnut baffles, respectively; In comparison, using the alternative sparger configurations had smaller effect (within ±30%) on the frequency.
The work also developed a modelling approach that predicted the biomass accumulation of P. tricornutum using the simulation results from Lagrangian particle tracking. To the best of the author’s knowledge, this was the first method that could predict the effect of different reactor designs and operating conditions (e.g. superficial gas velocity on algal biomass growth). The model simulation results, together with the reactor hydrodynamics simulated by CFD, could be used to guide the design of more light-efficient photobioreactors.
In summary, this thesis presented research in three directions of the development and optimization of a scalable process for producing EPA using photoautotrophic microalgae. Substantial, novel experimental data about the EPA productivity under industrially relevant conditions was generated for a range of species. For the first time a modelling approach was developed which provided accurate predictions of the biomass, EPA and total fatty acid concentrations. This model was found to work for a range of reactor designs, scales and operating conditions, and the approach developed here could be readily applied to other microalgal processes. Finally, the kinetic model was coupled with the results from CFD simulations to develop a novel modelling tool that can be used for the in-silico design of improved photobioreactor designs. Taken together the results from this work are a substantial step towards addressing the challenges in scaling-up microalgal EPA production. Successful scale-up of microalgae EPA production is key in ensuring people have a sustainable, affordable source of EPA.
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Leigh-Firbank, Elizabeth C. "The beneficial and adverse effects of increasing N-3 polyunsaturated fatty acids (PUFA) intake on coronary heart disease (CHD) biomarkers." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269723.
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Abekura, Yu. "Eicosapentaenoic acid prevents the progression of intracranial aneurysms in rats." Kyoto University, 2020. http://hdl.handle.net/2433/259723.
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Whitehouse, Alison Sarah. "Muscle catabolism in cancer and its attenuation by eicosapentaenoic acid." Thesis, Aston University, 2001. http://publications.aston.ac.uk/10945/.
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This work examines skeletal muscle catabolism in cancer and its attenuation by Eicosapentaenoic Acid (EPA). In vivo studies in mice bearing a cachexia inducing murine colon adenocarcinoma - MAC16, demonstrated an elevation in the gastrocnemius muscle in the activity and expression of regulatory components of the ubiquitin-proteasome proteolytic pathway. This was accompanied by an accelerated loss of muscle tissue correlating with an increase in overall weight loss, all of which were attenuated by prior daily dosing with EPA. Recently a proteolysis inducing factor (PIF) has been isolated from the MAC16 tumour, and from the serum and urine of cachectic cancer patients. Previous studies have shown that PIF induces protein degradation in vitro, and that this is possibly mediated through 15-hydroxyeicosatetraenoic acid (15-HETE), a metabolite of the n-6 polyunsaturated fatty acid- arachidonate. Employing the murine myoblast cell line C2C12, it was shown that both PIF and 15-HETE increased protein degradation and expression of proteasome subunits, processes which were again attenuated by prior incubation in EPA. Similarly, in NMRI mice which had been fasted for 24hours, EPA and the lipoxygenase inhibitor CV-6504 (but not structurally related fatty acids) inhibited skeletal muscle proteolysis and expression of various proteasome subunits, showing that firstly, EPA may be anti-cachexic partly through its ability to influence 15-HETE production; and secondly that the effect is specific for EPA as other fatty acids had no effect. Previous studies have suggested the involvement of the signal transduction family NFKB in response to PIF in the liver. It has been demonstrated here that both PIF and 15-HETE increased nuclear translocation of NFKB in the skeletal muscle of tumour bearing mice and that EPA inhibited this process by its ability to prevent the degradation of the NFKB inhibitor protein IKB. When an NFKB inhibitor was added to C2C12 myotubes, prior to the addition of PIF, proteasome activity and protein degradation was inhibited, showing that NFKB is responsible for the increased proteasome activity and muscle catabolism induced by PIF. Taken together this work suggests that 15-hydroxyeicosatetraenoic acid is the intracellular mediator for PIF induced protein degradation in skeletal muscle and that elevated muscle catabolism is accomplished through an increased functioning of the ubiquitin-proteasome pathway, a process possibly mediated through an NFKB dependent mechanism. The anticachectic (and possibly the anti-tumourigenic) effects of EPA appear to be achieved in part by its ability to inhibit the degradation of IKB and possibly by its ability to interfere with 15-HETE production.
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Jacobs, Annali. "The production of the highly unsaturated fatty acid eicosapentaenoic acid by fungal solid state fermentation." Thesis, Stellenbosch : Stellenbosch University, 2010. http://hdl.handle.net/10019.1/4500.
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Thesis (MSc (Microbiology))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: Long chain omega-3 fatty acids such as eicosapentaenoic acid (EPA) are essential for the regulation of critical biological functions in humans and other mammals. Fish oil as the main dietary source of EPA holds several disadvantages and alternative sources and production processes such as microbial fermentation are increasingly being investigated. Therefore the aim of the first part of this study was to evaluate brewers’ spent grain (BSG) as substrate for the production of EPA by solid state fermentation with 29 fungal strains representing different Mortierella species. The effect of a 10% (w/w) linseed oil (LSO) supplement on EPA production was also studied. Consequently, fungal inoculated BSG was incubated at 22oC for three days to obtain optimal fungal growth, before the incubation temperature was lowered to 16oC for the following eight days. Cultures were then harvested and dried, followed by lipid extraction and analyses using gas chromatography. All the strains were found to produce EPA on BSG, while addition of the LSO improved the EPA yield of most strains. The strains which produced the highest levels of EPA on BSG supplemented with LSO were Mortierella antarctica Mo 67 and Mortierella epicladia Mo 101, which respectively produced 2.8 mg and 2.5 mg EPA per g of BSG. During the second part of the study eight Mortierella strains were used to study EPA production via solid state fermentation of sunflower press cake (SPC). Similar culture conditions and analytical methods were used as in the first part of the study. The effect of supplementing the SPC substrate with 10% (w/w) LSO was studied with regard to the supplement’s impact on EPA production and on the highly unsaturated fatty acid (HUFA) profile of the fermented substrate. Addition of LSO improved EPA yield of most strains on SPC, leading to a reduction in the average arachidonic acid (ARA):EPA ratio from 50.68 to 3.66. The ratio of HUFA to saturated and monoenoic fatty acids, was increased significantly (t=5.75, p=0.05) by the addition of LSO, with higher desaturation levels among the 20-carbon fatty acids. Addition of LSO also had a positive effect (r = 0.9291, p = 0.001) on the relative amount of long chain fatty acids (C≥20) produced. The strains which produced the highest levels of EPA on SPC supplemented with LSO were Mortierella alpina Mo 46 and Mortierella basiparvispora Mo 88, which produced 6.4 mg and 5.8 mg EPA per g of sunflower press cake, respectively. Fungi belonging to the genus Mortierella successfully converted LSO supplemented agro-processing wastes, such as BSG and SPC, to materials containing EPA, thereby adding value to these substrates. These EPA-enriched waste substrates could eventually find applications as animal or fish feed or as a source of EPA and other HUFA for the growing omega-3 market in the neutraceutical and therapeutics industry.
AFRIKAANSE OPSOMMING: Langketting omega-3 vetsure soos eikosapentaenoë suur (EPS) is noodsaaklik vir die regulasie van kritiese biologiese funksies in mense en ander soogdiere. Visolie, die mees belangrike EPS-bron in die dieet, hou verskeie nadele in en alternatiewe bronne sowel as produksie-prosesse, soos mikrobiologiese fermentasie, word dus toenemend ondersoek. Die doel van die eerste gedeelte van hierdie studie was dus om gebruikte brouersgraan (GBG) te ëvalueer as ‘n substraat vir die produksie van EPS deur soliede staat fermentasie met 29 fungus isolate wat verskillende Mortierella spesies verteenwoordig. Die uitwerking van byvoeging van 10% (m/m) lynsaadolie (LSO) op EPS-produksie is ook bepaal. Gevolglik is fungus-geïnokuleerde GBG vir drie dae by 22oC geïnkubeer om optimale fungusgroei te verkry, waarna die inkubasie temperatuur verlaag is na 16oC vir die volgende agt dae. Kulture is hierna ge-oes en gedroog, gevolg deur lipied ekstraksie en analise met behulp van gaschromatografie. Al die isolate het EPS geproduseer op die GBG substraat, terwyl byvoeging van LSO die EPS-opbrengs van die meeste isolate verbeter het. Die isolate wat die hoogste vlakke van EPS op GBG wat met LSO verryk is, geproduseer het, was Mortierella antarctica Mo 67 en Mortierella epicladia Mo 101, wat onderskeidelik 2.8 mg en 2.5 mg EPS per g GBG geproduseer het. Tydens die tweede gedeelte van die studie is agt Mortierella isolate gebruik om die produksie van EPS deur soliede staat fermentasie van sonneblom perskoek (SPK) te ondersoek. Kultuurtoestande en analitiese metodes soortgelyk aan die eerste gedeelte van die studie is gebruik. Die uitwerking van byvoeging van 10% LSO tot die SPK substraat is ondersoek met betrekking tot die impak van die byvoeging op EPS produksie asook op die profiel van hoogs onversadigde vetsure (HOVS) van die gefermenteerde substraat. Die byvoeging van LSO tot SPK het die EPS opbrengs van meeste isolate verbeter en het tot ‘n verlaging in die gemiddelde arachidoonsuur (ARS):EPS verhouding vanaf 50.69 tot 3.66 gelei. Die verhouding van HOVS tot versadigde en mono-onversadigde vetsure, is betekenisvol (t=5.75, p=0.05) verhoog deur die byvoeging van LSO, met hoër vlakke van onversadigheid onder die 20-koolstof vetsure. Byvoeging van LSO het ook ‘n positiewe uitwerking (r = 0.9291, p = 0.001) op die relatiewe aantal langketting vetsure (C≥20) gehad. Die isolate wat die hoogste vlakke van EPS geproduseer het op LSO-verrykte SPK, was Mortierella alpina Mo 46 en Mortierella basiparvispora Mo 88, wat onderskeidelik 6.4 mg en 5.8 mg EPS per g SPK geproduseer het. Fungi wat aan die genus Mortierella behoort, het LSO-verrykte agroprosesserings afvalprodukte, soos GBG en SPK, suksesvol omgeskakel na materiale wat EPS bevat, en sodoende waarde toegevoeg aan hierdie substrate. Die EPS-verrykte afvalsubstrate kan uiteindelik toepassings vind as diere- of visvoer of as bron van EPS of ander HOVS vir die groeiende omega-3 mark in die neutraseutiese en terapeutiese industrie.
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Tokunaga, Tomohisa. "Synthesis and application of ω-ethynyl fatty acids to analyze the physiological functions of eicosapentaenoic acid." Kyoto University, 2018. http://hdl.handle.net/2433/232362.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第21161号
農博第2287号
新制||農||1060(附属図書館)
学位論文||H30||N5135(農学部図書室)
京都大学大学院農学研究科応用生命科学専攻
(主査)教授 栗原 達夫, 教授 小川 順, 教授 阪井 康能
学位規則第4条第1項該当
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Sato, Sho. "Chemical studies on physiological roles of eicosapentaenoic acid in bacterial membrane." Kyoto University, 2012. http://hdl.handle.net/2433/157709.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第16918号
農博第1934号
新制||農||1000(附属図書館)
学位論文||H24||N4679(農学部図書室)
29593
京都大学大学院農学研究科応用生命科学専攻
(主査)教授 栗原 達夫, 教授 小川 順, 教授 平竹 潤
学位規則第4条第1項該当
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Wächter, Simon Fabian [Verfasser]. "Effects of omega-3 fatty acids docosahexaenoic acid and eicosapentaenoic acid and their metabolites in acute inflammation / Simon Fabian Wächter." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2012. http://d-nb.info/103038133X/34.
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Brian, King Himm Mo. "Biochemical analysis and genetic engineering of oleaginous fungi for the production of eicosapentaenoic acid and free fatty acid derivatives." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263714.
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招志明 and Chi-ming Lawrence Chiu. "Possible mechanisms of arachidonic and eicosapentaenoic acids on humanleukemic cell proliferation and apoptosis by flow cytometric analysis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31236741.
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Athalye, Sneha Kishor. "Production of Eicosapentaenoic acid from biodiesel derived crude glycerol using fungal culture." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/34082.
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Omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA, C20:5, n-3) and docosahexaenoic acid (DHA, C22:6, n-3), have many medically established benefits against cardiovascular diseases, cancers, schizophrenia, and Alzheimerâ s. Currently, fish oil is the main source of omega-3 fatty acids, but there are many problems associated with it such as undesirable taste and odor, and heavy metal contamination. As a result, it is necessary to seek alternative production sources based on various microorganisms.
In this thesis we have developed a novel microfungal culture process to produce EPA from the crude glycerol byproduct generated in biodiesel industry. This process provides both an alternative source of omega-3 fatty acids and a benefit to the biodiesel industry. Indeed, as oil prices reach historical highs, biodiesel has attracted increasing interest throughout the United States. The disposal of the crude glycerol byproduct has been a challenge faced by the biodiesel producers.
Crude glycerol presents a cheap carbon source for growth of many microorganisms. In this thesis, we tested the feasibility of using crude glycerol for producing eicosapentaenoic acid (EPA, 20:5, n-3) by one algal species, Phaeodactylum tricornutum and two fungal species, Mortierella alpina and Pythium irregulare. We observed that the algal growth is inhibited in the crude glycerol while the fungi can grow very well in crude glycerol-containing medium. The fungus M. alpina produced significant amount of ARA but negligible amount of EPA. P. irregulare produced significant amount of biomass as well as a relatively high level of EPA. The maximum dry biomass for the P. irregulare culture was 2.9 g/L with an EPA productivity of 7.99 mg/L-day. Based on these results, we concluded that P. irregulare was a promising candidate for EPA production from biodiesel derived crude glycerol.
Further optimization work showed that P. irregulare grown 30 g/L crude glycerol and 10g/L yeast extract results in the highest level of EPA production. A temperature of 20o C is optimal for high fungal biomass and EPA levels. Addition of vegetable oil (at 1%) enhanced the EPA production and almost doubled the amount of biomass reached. Soap inhibits growth as well as EPA production severely even in small amounts. Methanol completely inhibits growth. The final optimized growth conditions for the fungus P.irregulare were a medium with 30g/L of crude glycerol, 10 g/L of yeast extract at a pH of 6 with 1% supplementation of oil, at a temperature of 20o C for a period of 7 days.Thus we have established that the fungus P.irregulare can be used successfully to produce high mounts of EPA from crude glycerol.Master of Science
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Dickson, Darin. "Development of an eicosapentaenoic acid production bioprocess using an indigenous microalgal isolate." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/13711.
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Eicosapentaenoic acid (EPA; 20:5) is an omega-3 polyunsaturated fatty acid of increasing interest as a nutraceutical. An indigenous microalgal isolate suitable for an EPA bioprocess was selected by screening monoalgal isolates from the Council for Scientific and Industrial Research (CSIR) micro-algal culture collection. A Cymbella diatom (A23.2) was selected for superior EPA production in both growth and stress conditions, using both fluorescent microscopy and flask studies. Studies investigated increasing biomass, improving EPA content, and optimising overall EPA productivity in a multi-stage bioprocess. Growth studies found self-regulatory systems in both phosphate and nitrate metabolism. These mechanisms were absent in silicate and bicarbonate consumption, prompting their optimisation in the bioprocess medium. Cultivation pH was found to have a statistically modelled optimal value of 7.2 and a light intensity at a low range of 60 – 70 ìmol.m-2.s-1 was found to be suitable. Nutrient and physicochemical parameters were assayed individually, and revealed cell productivities of between 2.0 x 108 to 3.0 x 108 cell.L-1.hr-1 in batch culture bioreactor studies. Further studies demonstrated the use of both nutrient stress and physicochemical stress to enhance EPA production. These results informed the choice of operating parameters for a proof of concept, multistage raceway-based EPA bioprocess, consisting of a single growth pond and three stress ponds linked in series. The growth phase EPA productivity data of 0.68 mg.L-1.day-1, was higher than that of the stress phase, supporting its classification as a growth-associated product. Further, the EPA productivity in the raceway was more than twice that of initial batch culture screening. Once experimental limitations are addressed, a re-design of the bioprocess can be undertaken by optimising growth phase residence time, medium flow-rate and partial/complete elimination of the stress phase. The EPA productivity of the diatom used in this work has the potential of reaching commercially viable values. The development of a commercial indigenous EPA producer has a dual impact, as it addresses various nutritional and medicinal market demands and improves the sustainability of the world’s fish stocks.
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Zaima, Nobuhiro. "Studies on formation mechanism and bioactivities of trans isomers of eicosapentaenoic acid." Kyoto University, 2007. http://hdl.handle.net/2433/136533.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第13114号
農博第1619号
新制||農||941(附属図書館)
学位論文||H19||N4240(農学部図書室)
UT51-2007-H387
京都大学大学院農学研究科応用生物科学専攻
(主査)教授 平田 孝, 教授 左子 芳彦, 助教授 菅原 達也
学位規則第4条第1項該当
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Chiu, Chi-ming Lawrence. "Possible mechanisms of arachidonic and eicosapentaenoic acids on human leukemic cell proliferation and apoptosis by flow cytometric analysis /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19737907.
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Prossomariti, Anna <1986>. "Chemopreventive effects of eicosapentaenoic acid free fatty acid in a murine model of colitis-associated colorectal cancer." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6918/.
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Inflammatory bowel diseases are associated with increased risk of developing colitis-associated colorectal cancer (CAC). Epidemiological data show that the consumption of ω-3 polyunsaturated fatty acids (ω-3 PUFAs) decreases the risk of sporadic colorectal cancer (CRC). Importantly, recent data have shown that eicosapentaenoic acid-free fatty acid (EPA-FFA) reduces polyps formation and growth in models of familial adenomatous polyposis. However, the effects of dietary EPA-FFA are unknown in CAC. We tested the effectiveness of substituting EPA-FFA, for other dietary fats, in preventing inflammation and cancer in the AOM-DSS model of CAC. The AOM-DSS protocols were designed to evaluate the effect of EPA-FFA on both initiation and promotion of carcinogenesis. We found that EPA-FFA diet strongly decreased tumor multiplicity, incidence and maximum tumor size in the promotion and initiation arms. Moreover EPA-FFA, in particular in the initiation arm, led to reduced cell proliferation and nuclear β-catenin expression, whilst it increased apoptosis. In both arms, EPA-FFA treatment led to increased membrane switch from ω-6 to ω-3 PUFAs and a concomitant reduction in PGE2 production. We observed no significant changes in intestinal inflammation between EPA-FFA treated arms and AOM-DSS controls. Importantly, we found that EPA-FFA treatment restored the loss of Notch signaling found in the AOM-DSS control, resulted in the enrichment of Lactobacillus species in the gut microbiota and led to tumor suppressor miR34-a induction. In conclusion, our data suggest that EPA-FFA is an effective chemopreventive agent in CAC.
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Madalozzo, Elisângela Serenato 1986. "Avaliação da oxidação do colesterol em sistemas modelo contendo ácidos graxos, mioglobina e antioxidantes naturais e sintéticos." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255278.
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Orientador: Neura BragagnoloTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O colesterol é um dos mais importantes esteróis existentes nos tecidos animais, podendo apresentar-se na forma livre ou como ésteres de colesterol. Comporta-se de maneira particular em relação à oxidação por apresentar uma ligação dupla entre o carbono 5 e 6 da estrutura cíclica, originando produtos de oxidação, denominados óxidos de colesterol (COP¿s), principalmente quando exposto a temperaturas elevadas, iniciadores de radicais, luz, metais ou à combinação destes fatores. Por isso, o objetivo deste trabalho foi constatar o impacto do uso de diferentes antioxidantes (eritorbato de sódio, bixina e ácido cítrico) na degradação térmica do colesterol em sistemas modelo na presença de metais (mioglobina) e de ácidos graxos com diferentes graus de insaturação (ácido oleico, ácido eicosapentaenoico - EPA e ácido palmítico) sob fluxo constante de O2 (10 mL/min). A ação dos antioxidantes, pró-oxidante e ácidos graxos foi monitorada pela degradação do colesterol e consequente formação de COP¿s e alteração na composição de ácidos graxos, bem como pela degradação dos antioxidantes adicionados aos sistemas modelo submetidos a temperaturas de 130, 160 e 230°C. Para avaliar a interação entre o colesterol e os diferentes compostos nos sistemas modelo foi realizado um planejamento experimental do tipo Plackett & Burman para cada temperatura estudada. Os resultados demosntraram que o sistema modelo constituído de colesterol, bixina, ácido oleico e mioglobina (ensaio 11) foi o que apresentou a maior degradação do colesterol e maior concentração de óxidos. Já o sistema modelo que apresentou a menor degradação do colesterol foi o 1 que apresenta em sua composição colesterol, eritorbato de sódio, ácido cítrico e mioglobina. Para a temperatura de 230°C os ensaios que apresentaram a menor degradação continham colesterol, eritorbato de sódio, ácido cítrico e mioglobina (ensaio 1) e eritorbato de sódio, bixina e ácido palmítico (ensaio 2). Cinco COP¿s foram identificados e quantificados nos sistemas (7-ceto, 7?-OH, 7?-OH, 5,6?-epóxido e 5,6?-epóxido). O óxido encontrado em maior quantidade nas temperaturas de 130 e 160°C foi o 5,6?-epóxido, já na temperatura de 230°C foi o 7-ceto. Esses resultados demonstram que a maior formação de COP¿s está diretamente relacionada com a maior degradação do colesterol nas temperaturas estudadas
Abstract: Cholesterol is one of the most important sterols in animal tissue in its free form or as esters. This compound presents an unique behavior in relation to oxidation since it has a double bond between carbons 5 and 6 of the cyclic structure, generating oxidation products, the so called cholesterol oxides (COP's), especially when exposed to high temperature, radical initiators, light, metal or a combination of these factors. Therefore, the aim of this study was to study the impact of different antioxidants (sodium erythorbate, citric acid and bixin) on thermal degradation of cholesterol in model systems in the presence of metals (myoglobin) and fatty acids with different degrees of unsaturation (oleic acid, eicosapentaenoic acid - EPA and palmitic acid) at constant O2 flow (10 ml/min). The effect of antioxidants, pro-oxidant and fatty acids was monitored by the degradation of cholesterol and the consequent formation of COP¿s, by the changes in the fatty acid composition, as well as by the degradation of the antioxidants added to model systems subjected to 130, 160 and 230°C. To evaluate the interaction between cholesterol and the different compounds present in the model systems a Plackett & Burman experimental design was carried out in each temperature. The model system containing cholesterol, bixin, oleic acid and myoglobin (sample 11) showed the highest degradation of cholesterol and concentration of COP¿s. The lowest degradation of cholesterol was observed in sample 1, containing cholesterol, sodium erythorbate, citric acid and myoglobin. At 230°C, the samples that showed the lowest degradation contained cholesterol, sodium erythorbate, citric acid and myoglobin (sample 1) and sodium erythorbate, bixin and palmitic acid (sample 2). Five COP's were identified and quantified in the model systems (7-keto, 7?-OH, 7?-OH, 5,6?-epoxide and 5,6?-epoxide). The COP present in the highest content at 130°C and 160°C was 5,6?-epoxide, and at 230°C, 7-keto. These results demonstrated that a high formation of COP¿s is directly related to a high degradation of cholesterol at the studied temperatures
Doutorado
Ciência de Alimentos
Doutora em Ciência de Alimentos
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Smit, Monique. "Evaluation of the competitive performance of an indigenous eicosapentaenoic acid producing microalgal isolate." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/13327.
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Includes bibliographical references.Omega-3 fatty acids are known to have positive effects on brain function, as well as cardiovascular disease and inflammatory diseases. They currently sold as fish oil concentrates. The fish oil extraction processes are unsustainable due to the diminishing fish stocks in open waters. In addition to this is the fact that the omega-3 fatty acid content in fish are directly dependent on the fish's diet. If the fish does not have access to nutrients containing omega-3s, the fish will not have assimilated the relevant fatty acids. Currently, microalgae are a topic of interest regarding omega-3 fatty acid production because they are the ultimate de nova source of omega-3 fatty acids. In order to mitigate long-term fish resource depletion, it is imperative that the cultivation of edible fish becomes a priority. However, these aquaculture fish will not contain omega-3 fatty acids if this is not a part of their diet, either naturally or as a feed additive. Due to microalgae's de nova production of omega-3 fatty acids, this would be an ideal alternative to fish oil, as well as a source of omega-3 fatty acids for cultivated fish as a feed input. South Africa is an ideal location for the commercialisation of microalgal technology, due to its biodiversity and climate. There is thus a desire to exploit the biodiversity of South Africa and over 750 microalgal isolates have been collected from across South Africa and are housed at the CSIR Biosciences and the Centre for Bioprocess Engineering (CeBER) at the University of Cape Town. The main objective of this study was to investigate whether a locally selected isolate was a more suitable organism for omega-3 fatty acid production in an open raceway pond than a current species of choice. The objectives of the study were achieved by investigating the biomass, EPA production and response to reactor configuration and process conditions, with a view to assessing the potential to further scale up the bioprocess. A literature review was conducted to identify a list of possible omega-3 producing candidates. The published data were analysed to reduce the overall list of potential organisms to six species. Initial experimental analysis indicated that Phaeodactylum tricornutum was a suitable control species against which to compare the locally selected isolate in terms of biomass and EPA production. Average specific growth rate and overall average EPA productivity were 0.24 d-1 and 10.85 ìg.d- 1 respectively for P. tricornutum. The chosen CSIR species, WCA 23.2, had an average specific growth rate and overall average EPA productivity of 0.20 d-1 and 7.83 ìg.d- 1 respectively. Molecular identification confirmed the identity of Phaeodactylum tricornutum and indicated WCA 23.2 most likely to be an Amphora species. Selected environmental factors, such as pH and different nutrient regimes were chosen to study the effect on growth rate, biomass production and EPA production under laboratory conditions. A study was devised to test the effects of pH control under maintained nutrient conditions. All studies were subjected to a period of nutrient deficiency for the last 4-6 days of the experiment to assess the effect on EPA induction. The pH studies resulted in similar average specific growth rates for both species under pH controlled vs. uncontrolled conditions with WCA 23.2 and P. tricornutum demonstrating growth rates of 0.20-0.22 d-1 and 0.30-0.33 d-1 respectively. Specific EPA productivity was negatively affected for both species in the absence of pH control, where- the pH increased to above pH 9.4. For the pH studies, there was no observed increase in EPA content under nutrient (nitrate and silicon) deficient conditions. Subsequent experiments were performed with the pH controlled at pH 8.3 to ensure optimal biomass and specific EPA production. To evaluate the impact of different nutrient addition regimes at a chosen pH, a study was designed to supply cultures with the same amount of nutrients where (1) the batch culture had all the nutrients supplied at the start and (2) a fed-batch regime where smaller amounts of nutrients were supplied every second day. Average specific growth rates were similar for both species under batch and fed-batch conditions with values ranging from 0.23-0.25 d-1. Specific EPA productivities, however, were higher for both cultures when cultivated under the batch conditions with productivities of 0.412 mg.g-1d and 0.175 mg.g-1d for WCA-23.2 and P. tricornutum respectively. To assess the impact of scale-up, biomass and specific EPA production was assessed in an open raceway pond system (SO L volume) where species were cultivated, in duplicate, under batch conditions at a pH of 8.3, relying on the environmental temperatures and natural sunlight. Biomass productivities for both cultures were significantly lower when compared to the productivities from the laboratory scale studies. Biomass productivity was 2.5 times lower for WCA 23.2 and five-fold lower for P. tricornutum. In terms of specific EPA production, WCA 23.2 suffered a 4.5 fold loss while specific EPA production in P. tricornutum was 20% higher. While the locally selected isolate had a lower specific EPA production rate, it was quicker and easier to harvest. WCA 23.2 auto-flocculated and could be sieved within an hour, while P. tricornutum required an additional settling step to harvest the biomass, resulting in an overall harvesting phase that took two days. The experimental data indicated that EPA productivity was higher in P. tricornutum than WCA 23.2, under the conditions tested. However, the ease of biomass recovery and regulatory advantages associated with using an endemic species mean that a more thorough economic evaluation is required to draw a definitive conclusion.
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Rodrigues, Ana Sofia de Figueiredo. "Industrial production of omega-3 polyunsaturated fatty acids from fish oil and microalgae." Master's thesis, ISA/UTL, 2012. http://hdl.handle.net/10400.5/5257.
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Mestrado em Engenharia Alimentar - Instituto Superior de Agronomiaω-3 polyunsaturated fatty acids (PUFAs) ingredients, especially eicosapentaenoic acid (EPA, 20:5ω3) and docosahexaenoic acid (DHA, 22:6ω3) are known for its vital and unique role in human health and well-being by an extensive scientific research. These facts are widely spread by media. At present, the major source of ω-3 PUFAs is fish oil from oily fish like sardine (Sardina pilchardus). This work proposes the use of heterotrophic microalgae such as Crypthecodinium cohnii as an alternative source of interest for the commercial production of ω-3 EPA and DHA. It is also suggested the use of a common process suitable for both feedstock. EPA and/or DHA production are accomplished through oil saponification and PUFAs concentration winterization and urea concentration. PUFAs purification by chromatography is only necessary when oil is extracted from fish since fractions obtained from C. cohnii have high proportions in DHA and they do not require further purification steps for food applications. The combination of traditional (seasonal) and alternative sources (year-round) using a common production process shows an economic advange with increasing earnings for market development.
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Dippenaar, Henda. "Dietary supplementation with eicosapentaenoic acid in patients with schizophrenia : neuropsychological evaluation of cognitive functioning." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52791.
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Thesis (MA)--University of Stellenbosch, 2002.ENGLISH ABSTRACT: Schizophrenia is known to produce positive (e.g. hallucinations) and negative symptoms (e.g. social withdrawal). Cognitive dysfunction has long been recognised as common in schizophrenia and is now accepted as a third cardinal feature, thought strongly to be associated with negative symptoms. While positive symptoms may respond well to antipsychotic medication, the negative symptoms have typically been resistant to all forms of intervention. A current study looking at the efficacy of Eicosapentaenoic Acid (EPA), indicated a potential for negative symptoms to improve, although not significantly (P=O.14). The purpose of this research was to expand the above mentioned study, by evaluating the potential of EPA for improving cognitive function in patients with schizophrenia. Forty patients diagnosed with schizophrenia were randomly ascribed to one of two groups in a 12 week, double-blind, placebo-controlled study. The following neuropsychological tests were administered to patients at baseline and end point: Mini Mental State Examination (MMSE); Rey Auditory-Verbal Learning Test (RAVLT); Visual Reproduction, Wechsler Memory Scale - Revised (VR, WMS-R); Rey-Osterreith Complex Figure Test (ROCFT); Trail Making Tests (TMT-A; TMTB); Controlled Oral Word Association Test (COWAT); Similarities, South African Wechsler Adult Intelligence Scale - Revised (Similarities, SAWAIS-R); Boston Naming Test (BNT). There were no overall significant differences in neuropsychological function between the experimental (EPA) and the control (Placebo) group. In some isolated tests the experimental group did significantly better than the control group, but for other tests the control group did significantly better than the experimental group. Large intragroup variation - particularly within the EPA group - was indicated. In the EPA group only one out of 25 independent neuropsychological test scores showed a significant correlation with the symptom severity on the Positive and Negative Syndrome Scale (PANSS) total score (% change). There were no significant correlations between any of the neuropsychological test scores in the EPA group and on the dyskinesia subscore of the Extrapyramidal Symptom Rating Scale (ESRS). There was no evidence to support the hypothesis that EPA improved cognitive functioning in patients with schizophrenia.
AFRIKAANSE OPSOMMING: Dit is bekend dat skisofrenie positiewe (bv. hallusinasies) en negatiewe simptome (bv. sosiale onttrekking) voortbring. Kognitiewe disfunksie word lank reeds beskou as algemeen in skisofrenie en word nou aanvaar as 'n derde kardinale eienskap wat sterk geassosieer word met negatiewe simptome. Terwyl positiewe simptome goed reageer op antipsigotiese medikasie, is die negatiewe simptome tipies meer weerstandig teen all vorme van intervensie. 'n Huidige studie wat die effektiwiteit van Eicosapentaenoic Acid (EPA) ondersoek, het 'n potensiaal vir die verbetering in negatiewe simptome aangedui, alhoewel nie beduidend nie (P=O.14). Die doel van hierdie navorsing was om bogenoemde studie uit te brei, deur te evalueer wat die potensiaal van EPA is om kognitiewe simptome in pasiente met skisofrenie te verbeter. Veertig pasiente gediagnoseer met skisofrenie is ewekansig toegewys aan een van twee groepe in 'n 12 weke, dubbel-blinde, plasebo-gekontroleerde studie. Die volgende neurosielkundige toetse is afgeneem op pasiente by basislyn en eindpunt: Mini Mental State Examination (MMSE); Rey Auditory-Verbal Learning Test (RAVLT); Visual Reproduction, Wechsler Memory Scale - Revised (VR, WMS-R); Rey-Osterreith Complex Figure Test (ROCFT); Trail Making Tests (TMT-A; TMT-B); Control/ed Oral Word Association Test (COWAT); Similarities, South African Wechsler Adult Intelligence Scale - Revised (Similarities, SAWAIS-R); Boston Naming Test (BNT). Daar was geen beduidende verskille in neurosielkundige funksionering tussen die eksperimentele (EPA) en kontrole (Plasebo) groep nie. In 'n paar geïsoleerde toetse het die eksperimentele groep beduidend beter as die kontrolegroep gevaar, maar op ander toetse het die kontrolegroep beduidend beter as die eksperimentele groep gevaar. Groot intragroep variansie - in veral die EPA groep is aangetref In die EPA groep het slegs een uit die 25 onafhanklike neurosielkundige toetstellings gedui op 'n beduidende korrelasie met die ems van simptome op die Positive and Negative Syndrome Scale (PANSS) totale telling (% verandering). Daar was geen beduidende korrelasie tussen enige van die neurosielkundige toetstellings in die EPA groep en op die diskinesie-subtelling op die Extrapyramidal Symptom Rating Scale (ESRS) nie. Daar was geen bewyse om die hipotese te steun dat EPA kognitiewe funksionering in pasiënte met skisofrenie verbeter nie.
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Kajikawa, Satoshi. "Effects of Eicosapentaenoic Acid on the Hepatic Lipid Metabolism and the Progression of Steatohepatitis." Kyoto University, 2011. http://hdl.handle.net/2433/147373.
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Gong, Chunjie. "Characterization of Proteins Involved in the Biosynthesis of Eicosapentaenoic Acid in Shewanella livingstonensis Ac10." Kyoto University, 2013. http://hdl.handle.net/2433/175069.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第17640号
農博第2002号
新制||農||1012(附属図書館)
学位論文||H25||N4761(農学部図書室)
30406
京都大学大学院農学研究科応用生命科学専攻
(主査)教授 栗原 達夫, 教授 植田 充美, 教授 小川 順
学位規則第4条第1項該当
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Zhang, Zhao 1960. "Studies on mechanisms of delayed puberty in female rats effected by dietary eicosapentaenoic acid." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278267.
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Marine oils contain eicosapentaenoic acid, a fatty acid that competes for cyclooxygenase and reduces the synthesis of dienoic prostanoids including prostaglandin E2 (PGE2). Since PGE2 plays an important role in the release of hypothalamic GnRH and the maturation of ovarian follicles and ova release, it was postulated that a diet containing fish oil (FO) would delay first ovulation through inhibitory effects on GnRH release, follicle development and ovulation. Immature female Sprague-Dawley rats were fed a FO diet ad libitum. Controls were pair-fed an identical diet with the substitution of safflower oil. The age of the FO-fed rats was significantly increased at first estrus, and first ovulation was either delayed or inhibited. Preoptic area/hypothalamic and ovarian PGE2 levels were reduced by FO feeding whereas hypothalamic GnRH was significantly increased. A FO-containing diet may delay the onset of puberty through attenuation of preovulatory GnRH release and local impairment of the ovulatory process.
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Mir, Adnan A. "The effect of eicosapentaenoic acid on brain and platelet produced bioactive lipid mediators. The effect of eicosapentaenoic acid, docosapentaenoic acid and other polyunsaturated fatty acids on the eicosanoids and endocannabinoids produced by rat brain and human platelets using electrospray ionisation tandem mass spectrometry-based analysis." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4281.
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Eicosapentaenoic acid (EPA) is a polyunsaturated fatty acid (PUFA) with neuroprotective and cardioprotective properties. It is thought that some of the actions of EPA may be attributed to its elongated metabolite, the PUFA docosapentaenoic acid (DPA). Docosahexaenoic acid (DHA) and arachidonic acid (AA) are bioactive PUFA ubiquitously expressed in neural tissues. EPA and AA can be converted by cyclooxygenase (COX) to prostanoids and by lipoxygenase (LOX) to hydroxy fatty acids. PUFA can also be converted to ethanolamides in the brain. These mediators are involved in physiological and pathological processes in many bodily systems.
The purpose of this study was to examine the production of eicosanoids, hydroxy fatty acids and fatty acid ethanolamides in young and aged rat brain following EPA or DPA enriched diets. The effects of specific PUFA on human platelet eicosanoid production were also investigated as these mediators play a role in adhesion and aggregation. Liquid chromatography coupled to tandem mass spectrometry (LC/ESI-MS/MS) assays were developed and used to measure lipid mediators in rat brain and human platelets.
Ageing in rat brain was accompanied with several changes in the prostanoid and hydroxy fatty acid profiles. Supplementing the diet with EPA or DPA at a daily dose of 200 mg/kg for 8 weeks prevented these changes and decreased levels of PGE2. DPA changed the profile of hydroxy fatty acids synthesised in the brain tissue of young animals. This study has shown that levels of eicosapentaenoylethanolamide (EPA-EA) increase in the brain as a result of ageing and that this is accompanied by an increase in levels of anandamide. Feeding aged animals EPA or DPA further increased the levels of EPA-EA but prevented any change in the level of anandamide.
Niacin is used to treat hypercholesterolaemia although it is associated with an unpleasant PGD2 mediated skin flush. This exploratory study has shown that human platelets treated with niacin did not show any changes in their prostanoid and hydroxy fatty acid profiles. Platelets treated with EPA showed increased production of TXB3 and 12-HEPE. Niacin augmented the effects of EPA on human platelet mediator synthesis.
Overall, this study has demonstrated that EPA can change brain and platelet lipid mediator synthesis and has provided evidence that could explain some of the neuroprotective and cardioprotective actions of this PUFA.
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Mir, Adnan Ahmed. "The effect of eicosapentaenoic acid on brain and platelet produced bioactive lipid mediators : the effect of eicosapentaenoic acid, docosapentaenoic acid and other polyunsaturated fatty acids on the eicosanoids and endocannabinoids produced by rat brain and human platelets using electrospray ionisation tandem mass spectrometry-based analysis." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4281.
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Eicosapentaenoic acid (EPA) is a polyunsaturated fatty acid (PUFA) with neuroprotective and cardioprotective properties. It is thought that some of the actions of EPA may be attributed to its elongated metabolite, the PUFA docosapentaenoic acid (DPA). Docosahexaenoic acid (DHA) and arachidonic acid (AA) are bioactive PUFA ubiquitously expressed in neural tissues. EPA and AA can be converted by cyclooxygenase (COX) to prostanoids and by lipoxygenase (LOX) to hydroxy fatty acids. PUFA can also be converted to ethanolamides in the brain. These mediators are involved in physiological and pathological processes in many bodily systems. The purpose of this study was to examine the production of eicosanoids, hydroxy fatty acids and fatty acid ethanolamides in young and aged rat brain following EPA or DPA enriched diets. The effects of specific PUFA on human platelet eicosanoid production were also investigated as these mediators play a role in adhesion and aggregation. Liquid chromatography coupled to tandem mass spectrometry (LC/ESI-MS/MS) assays were developed and used to measure lipid mediators in rat brain and human platelets. Ageing in rat brain was accompanied with several changes in the prostanoid and hydroxy fatty acid profiles. Supplementing the diet with EPA or DPA at a daily dose of 200 mg/kg for 8 weeks prevented these changes and decreased levels of PGE2. DPA changed the profile of hydroxy fatty acids synthesised in the brain tissue of young animals. This study has shown that levels of eicosapentaenoylethanolamide (EPA-EA) increase in the brain as a result of ageing and that this is accompanied by an increase in levels of anandamide. Feeding aged animals EPA or DPA further increased the levels of EPA-EA but prevented any change in the level of anandamide. Niacin is used to treat hypercholesterolaemia although it is associated with an unpleasant PGD2 mediated skin flush. This exploratory study has shown that human platelets treated with niacin did not show any changes in their prostanoid and hydroxy fatty acid profiles. Platelets treated with EPA showed increased production of TXB3 and 12-HEPE. Niacin augmented the effects of EPA on human platelet mediator synthesis. Overall, this study has demonstrated that EPA can change brain and platelet lipid mediator synthesis and has provided evidence that could explain some of the neuroprotective and cardioprotective actions of this PUFA.
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Richter, Chesney K., Kate J. Bowen, Dariush Mozaffarian, Penny M. Kris-Etherton, and Ann C. Skulas-Ray. "Total Long-Chain n-3 Fatty Acid Intake and Food Sources in the United States Compared to Recommended Intakes: NHANES 2003–2008." SPRINGER HEIDELBERG, 2017. http://hdl.handle.net/10150/626117.
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The American Heart Association recommends consuming fish (particularly oily fish) at least two times per week, which would provide ae 0.5 g/day of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) for cardiovascular disease risk reduction. Previous analyses indicate that this recommendation is not being met; however, few studies have assessed different ethnicities, subpopulations requiring additional n-3 fatty acid intake (i.e., children and pregnant and/or lactating women), or deciles of intake. Data from the National Health and Nutrition Examination Survey 2003-2008 was used to assess n-3 fatty acid intake from foods and supplements in the US population, according to age, sex, and ethnicity. A unique "EPA equivalents" factor, which accounts for potential conversion of shorter-chain n-3 fatty acids, was used to calculate total long-chain n-3 fatty acid intake. Data are reported for 24,621 individuals. More than 90% consumed less than the recommended 0.5 g/day from food sources (median = 0.11 g/day; mean = 0.17 g/day). Among the top 15% of n-3 fatty acid consumers, fish was the largest dietary contributor (71.2%). Intake was highest in men aged 20 years or more, and lowest in children and women who are or may become pregnant and/or are lactating. Among ethnicities, intake was lowest in Mexican-Americans. Only 6.2% of the total population reported n-3 fatty acid supplement use, and this did not alter median daily intake. Additional strategies are needed to increase awareness of health benefits (particularly among Mexican-Americans and women of childbearing age) and promote consumption of oily fish or alternative dietary sources to meet current recommendations.
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溫志友 and Zhiyou Wen. "A high yield and productivity strategy for eicosapentaenoic acid production by the diatom Nitzschia laevis in heterotrophic culture." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31242418.
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Wen, Zhiyou. "A high yield and productivity strategy for eicosapentaenoic acid production by the diatom Nitzschia laevis in heterotrophic culture." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23242097.
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McDaniel, J., Karen A. Massey, and Anna Nicolaou. "Fish oil supplementation alters levels of lipid mediators of inflammation in microenvironment of acute human wounds." Wiley, 2010. http://hdl.handle.net/10454/4577.
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noChronic wounds often result from prolonged inflammation involving excessive polymorphonuclear leukocyte activity. Studies show that the omega-3 polyunsaturated fatty acids eicosapentaenoic and docosahexaenoic acids found in fish oils generate bioactive lipid mediators that reduce inflammation and polymorphonuclear leukocyte recruitment in numerous inflammatory disease models. The purpose of this study was to test the hypotheses that boosting plasma levels of eicosapentaenoic and docosahexaenoic acids with oral supplementation would alter lipid mediator levels in acute wound microenvironments and reduce polymorphonuclear leukocyte levels. Eighteen individuals were randomized to 28 days of either eicosapentaenoic + docosahexaenoic acid supplementation (Active Group) or placebo. After 28 days the Active Group had significantly higher plasma levels of eicosapentaenoic (p<0.001) and docosahexaenoic acid (p<0.001) than the Placebo Group and significantly lower wound fluid levels of two 15-lipoxygenase products of omega-6 polyunsaturated fatty acids, [9- hydroxyoctadecadienoic (HODE) acid (p = 0.033) and15-hydroxyeicosatrienoic acid (HETrE) (p = 0.006)], at 24 hours post wounding. The Active Group also had lower mean levels of myeloperoxidase, a leukocyte marker, at 12 hours and significantly more re-epithelialization on Day 5 post wounding. We suggest that lipid mediator profiles can be manipulated by altering polyunsaturated fatty acid intake to create a wound microenvironment more conducive to healing.
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Hutchinson, John Michael. "Investigation of resolvin E1 as a metabolite of eicosapentaenoic acid with anti-colorectal cancer activity." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/15456/.
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Eicosapentaenoic acid (EPA) is an omega (ω)-3 polyunsaturated fatty acid (PUFA) found at high levels in oily fish such as salmon and mackerel. EPA has been shown to have anti-colorectal cancer (CRC) effects in two clinical studies where it was shown to reduce polyp burden in familial adenomatous polyposis (FAP) patients, and possibly improve overall survival in patients following liver resection for CRC liver metastases. At present, it is unknown how EPA exerts its anti-CRC effects. Resolvin E1 (RvE1) is a lipid with anti-inflammatory and pro-resolving activities derived from EPA. RvE1 biosynthesis requires three enzymes; aspirin acetylated cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX) and leukotriene A4 hydrolase (LTA4H). RvE1 has been shown to mediate its anti-inflammatory effects through two different G-protein coupled receptors, ChemR23 and BLT1. The hypothesis was that RvE1 synthesised within CRC could induce CRC cell apoptosis through either or both ChemR23 and BLT1 receptor signaling. ChemR23 and BLT1 protein were found to be expressed by human CRC clinical samples. ChemR23 and BLT1 were expressed at lower levels in histologically normal colorectal epithelium when compared to CRC, a relationship also seen with the associated stroma. No RvE1 mediated effect on CRC survival or apoptosis was identified on ChemR23 expressing human CRC cell lines in vitro. There was no BLT1 expression by human CRC cells in vitro. Human polymorphonuclear leukocytes (PMNs) treated directly with 18- hydroxyeicosapentaenoic acid (18-HEPE) generated RvE1. In vitro CRC cells and macrophages alone and in a transcellular synthesis model failed to produce RvE1. In conclusion, ChemR23 and BLT1 receptors were found to be expressed by human CRC clinical samples. RvE1 was not synthesised by a CRC model in vitro. The candidate identified no in vitro RvE1 biological activity. Further research could look to establish whether RvE1 can be detected in human CRC samples.
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Barber, Matthew David. "Metabolic abnormalities in advanced pancreatic cancer and their modulation by an eicosapentaenoic acid-based preparation." Thesis, University of Glasgow, 2001. http://theses.gla.ac.uk/2118/.
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A combination of a nutritional supplement and eicosapentaenoic acid was given to patients with advanced pancreatic cancer to assess its effect on the ongoing cachectic process. The administration of a fish oil-enriched nutritional supplement providing 2g eicosapentaenoic acid and around 600kcal per day resulted in a significant change in the metabolic disposition of patients with advanced pancreatic cancer. Consumption of the supplement resulted in a reversal of weight loss and a gain in lean body mass in association with a reversal of negative nitrogen balance. Performance status and appetite improved. Production of interleukin-6 was reduced and the acute phase protein response stabilised, insulin concentration increased and proteolysis inducing factor excretion fell. These changes were associated with a rise in energy intake, a fall in relative resting energy expenditure and a normalisation of the metabolic response to feeding and substrate utilisation. The increase in acute phase protein synthesis with feeding was abolished after the administration of the fish oil-enriched nutritional supplement. The progressive nutritional and functional deterioration of advanced pancreatic cancer patients thus seems to be associated with broadly pro-inflammatory metabolic mediators and a progressive acute phase protein response. This deterioration may in part be resistant to conventional nutritional supplementation because of further stimulation of acute phase protein production by feeding. The provision of a fish oil-enriched nutritional supplement normalises the metabolic milieu, stabilises the acute phase protein response and abolishes the stimulation of acute phase protein production by feeding. One explanation to account for the effects observed after intervention would be that it to allows dietary amino acids to be used for lean tissue anabolism with the consequent potential for quality of life and survival benefit.
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Sima, Corneliu. "Resolvin E1 actions on polymorphonuclear neutrophils in diabetes." Thesis, Boston University, 2010. https://hdl.handle.net/2144/32698.
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Dissertation (DScD) -- Boston University, Henry M. Goldman School of Dental Medicine, 2010 (Department of Periodontology and Oral Biology).Diabetes and periodontal disease exhibit a bidirectional relationship centered on an enhanced inflammatory response manifested both locally and systemically. The observation that hyperglycemia by itself, in the absence of additional inflammatory signals, promotes a proinflammatory environment indicates that diabetes is an independent risk factor for periodontal disease. Leukocyte pre-activation or priming in diabetes has been demonstrated. Excessive ROS release by leukocytes, upregulation of pro-inflammatory mediators and adhesion molecules are characteristic to T2DM-associated low-grade inflammation. However, the mechanisms by which chronic hyperglycemia leads to leukocyte activation are not fully understood. [TRUNCATED]
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Ethier, Shannon Elizabeth. "Producing Omega-3 Polyunsaturated Fatty Acids from Biodiesel Waste Glycerol by Microalgae Fermentation." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/32716.
Full textAbstract:
Crude glycerol is a major byproduct if the biodiesel industry. Biodiesel manufacturers are currently facing the challenges of appropriate disposal of this waste material. Crude glycerol is expensive to purify for use in food, cosmetic, and pharmaceutical industries and therefore, alternative methods for use of this crude glycerol are needed. A promising alternative is to use this crude glycerol as a carbon source for microalgae fermentation.
In this project, we investigated the use of crude glycerol as a less expensive substrate for the fermentation of the microalgae Schizochytrium limacinum and Pythium irregulare which are prolific producers of omega-3 polyunsaturated fatty acids. Omega-3 fatty acids have many beneficially effects on treating human diseases such as cardiovascular diseases, cancers, and neurological disorders. In addition, the omega-3 fatty acids docosahexaenoic acid (DHA) has been shown to be an important factor in infant brain and eye development.
The first part of this study focused on the continuous fermentation of S. limacinum, a prolific producer of DHA. The objective of this study was to examine the algal cellular physiology and maximize its DHA productivity. Two important parameters used in continuous fermentation were studied: dilution rate (D) and feed glycerol concentration (S0). The highest biomass productivity of 3.88 g/L-day was obtained at D = 0.3 day-1 and S0 = 60 g/L, while the highest DHA productivity (0.52 g/L-day) was obtained at D = 0.3 day-1 and S0 = 90 g/L. The cells had a true growth yield of 0.283 g/g, a maximum specific growth rate of 0.692 day-1, and a maintenance coefficient of 0.2216 day-1.
The second part of this study focused on morphology issues with P. irregulare, a prolific producer of eicosapentaenoic acid (EPA). P. irregulare has a filamentous morphology, which can make fermentation difficult. The mycelium can stick to the agitation blades resulting in mechanical problems. In addition, this filamentous morphology prevents adequate amounts of oxygen from reaching some cells resulting in decreased productivities. The focus of this research was to control the fermentation conditions to make the algae grow in small pellets, a morphology more suitable for fermentation. In flask culture studies, pellets were formed at an agitation speed of 110 rpm in both regular and baffled flasks. Baffled flasks resulted in pellet formation at 90 and 130 rpm as well. Fermentation studies resulted in pellet formation at agitation speeds of 150 and 300 rpm. Pellets were better able to form when a baffle was not in place. In addition, agitation speed influenced pellet size, with smaller pellets forming at the higher agitation speed.
Overall, this study showed that crude glycerol can be used as a carbon source for the continuous fermentation of S. limacinum with high DHA productivity and the morphology of P. irregulare could be controlled by manipulating culture conditions, mainly agitation speed. These results show the potential for scale-up studies for both algal species.Master of Science
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Conto, Leilane Costa de 1984. "Production of microcapsules containing fish oil omega-3 polyunsatureted fatty acid ethyl esters = Produção de microcápsulas contendo éster etílico de ácidos graxos polinsaturados ômega-3 de óleo de peixe." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255088.
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Orientador: Lireny Aparecida Guaraldo GonçalvesTexto em português e inglês
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-21T10:35:40Z (GMT). No. of bitstreams: 1 Conto_LeilaneCostade_D.pdf: 5195999 bytes, checksum: 05ac9b9628d2dacdf94c6fa8c8ba673f (MD5) Previous issue date: 2012
Resumo: Óleos e gorduras são importantes na alimentação humana como fonte de energia,além de alguns serem considerados essenciais ao funcionamento dos organismos, tais como determinados ácidos graxos polinsaturados ômega-3. O ácido eicosapentaenóico (EPA) e o ácido docosahexaenóico (DHA), provenientes de fontes marinhas, são as principais formas de ingestão direta de ômega-3,porém estes são muito sensíveis à oxidação e apresentam flavors característicos que levam à rejeição por alguns consumidores. Uma alternativa para contornar estes problemas é a microencapsulação. Uma técnica muito difundida para este tipo de produto sensível é a coacervação, no entanto algumas novas técnicas vêm surgindo na busca de solução destas deficiências. A gelificação enzimática pode ser citada como uma nova tecnologia que objetiva reduzir algumas etapas do processo e tempo de produção, se comparado ao processo de coacervação.Neste trabalho buscou-se compreender o comportamento do material de recheio (éster etílico de óleo de peixe), visto que são encontrados poucos estudos referentes às análises da integridade dos materiais de recheio de natureza lipídica quando encapsulados, e dos materiais de parede (principalmente isolado protéico de soja e isolado protéico de soro) quando utilizados para a produção de microcápsulas por gelificação enzimática e por coacervação complexa, avaliando tanto as cargas eletrostáticas do meio pelo seu potencial zeta para a coacervação, quanto na caracterização completa das cápsulas produzidas por gelificação enzimática e coacervação. Entre os materiais de parede estudados, foram utilizados isolado protéico de soro e isolado protéico de soja, sendo que este último na concentração de 10% apresentou formação de microcápsulas com características superiores pela técnica de gelificação enzimática. Quando estudadas mais a fundo as características das microcápsulas produzidas por gelificação enzimática, a ánalise do material encapsulado constatou-se que ocorreu a encapsulação de óleo de milho da segunda emulsão, reduzindo assim a eficiência real de encapsulação, mostrando-se assim uma técnica não eficaz,mesmo se obtendo cápsulas com elevada resistência mecânica. Comparando-se os métodos de degradação destas cápsulas, foi observada a total degradação da parede para a metodologia de degradação ácida, e parcial para a metodologia de degradação enzimática alcalina. Entretanto a melhor metodologia de degradação para se determinar a composição do material encapsulado foi a degradação ácida com determinação direta da composição em ácidos graxos. No estudo estatístico de microcápsulas contendo éster etílico de óleo de peixe produzidas por coacervação complexa utilizando isolado protéico de soja e goma arábica como material de parede obteve-se cápsulas contendo mais de 20 g de EPA + DHA / 100 g microcápsulas, sendo necessária a adição de menos de 0,5 g de microcápsulas em porções de 100 g ou 100 mL de alimentos para este poder ser considerado funcional. Contudo, uma grande variação no processo foi observadalevando a um estudo mais aprofundado do processo de coacervação através do potencial zeta dos materiais de parede e de recheio separadamente e em diferentes misturas, onde foi constatado que o isolado protéico de soja, por possuir variação na sua constituição e baixa solubilidade, dificulta a determinação exata do potencial zeta zero das misturas, sendo a máxima eficiência de encapsulação encontrada quando as misturas de 1,5:1,0 (massa:massa) isolado protéico de soja:Goma arábica e 2,0:1,0 (massa:massa) material de parede:material de recheio em pH 4,0 foram testados
Abstract: Fats and oils are important energy sources in human feeding, and some, such as the omega-3 polyunsaturated fatty acids, are considered essential to the functioning of the organisms. Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids from marine sources are the principal forms used for the direct ingestion of omega-3, but are highly sensitive to oxidation and present characteristic flavors leading to their rejection by some consumers. One alternative to overcome these problems is microencapsulation, and one well known technique for this type of sensitive product is coacervation, although some new techniques are currently appearing which also attempt to overcome these deficiencies.Enzymatic gelation could be cited as a new technology which aims to reduce some of the processing steps and production time when compared to coacervation. This work aimed to understand the behavior of the core material (fish oil ethyl ester),since few studies can be found referring to analyses of the integrity of the core materials of a lipid nature when encapsulated, and of the wall materials (principally soy protein isolate and whey protein isolate), when used in the production of microcapsules by enzymatic gelation and by complex coacervation, evaluating both the electrostatic charges in the medium from their zeta potential for coacervation, and a complete characterization of the resulting capsules produced by both enzymatic gelation and coacervation. Of the wall materials studied, whey protein isolate and soy protein isolate were used, the latter, at a concentration of 10%, producing microcapsules with the best characteristics by the enzymatic gelation technique. However, when the characteristics of the microcapsules produced by enzymatic gelation were studied at greater depth, the analysis of the core material showed that lipid material from another source had been coencapsulated due to the processing conditions, thus reducing the true efficiency of the encapsulation, showing that this technique was not efficient, despite the elevated mechanical resistance of the microcapsules. A comparison of the methods used to degrade the capsules showed total degradation of the wall by the acid degradation methodology, and only partial degradation for the enzymatic alkaline degradation methodology. Thus the best degradation methodology to determine the composition of the encapsulated material was acid degradation with the direct determination of the fatty acid composition. In the statistical study of the production of microcapsules containing fish oil ethyl ester by complex coacervation using soy protein isolate and gum Arabic as the wall materials, capsules were obtained containing more than 20 g EPA + DHA / 100 g of microcapsules, requiring the addition of less than 0.5 g of microcapsules to 100 g or 100 mL portions of foods for the food to be considered functional. However considerable process variation was observed, leading to a study in greater depth of the coacervation process as from the zeta potential of the wall and core materials separately, and in different mixtures. Thus it was shown that the soy protein isolate presented variation in its constitution and low solubility, which made it difficult to determine the exact zero zeta potential of the mixtures, the maximum encapsulation efficiency being found with mixtures of 1.5:1.0 (w:w) soy protein isolate: gum Arabic as the wall material and a ratio of 2.0:1.0 (w:w) for the wall material: core material at pH 4.0
Doutorado
Tecnologia de Alimentos
Doutora em Tecnologia de Alimentos
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Nascimento, Vera LÃcia Viana do. "Development of chemical process for synthesis of polyunsaturated esters." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13741.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoThis work aimed to develop refining processes, chemical alcoholysis followed by separation of fatty acids using the complexation with urea technique for the synthesis of poly-unsaturated esters from waste of fish oils. The special crude fish oil was purchased from Company Campestre - SÃo Paulo. Initially this oil has undergone a process of physical and chemical refining. From the refined oil, an alcoholysis process was carried out to obtain the mixture of free fatty acids. From the hydrolyzed material were obtained 32.78% p/p of PUFAs against 19.73% p/p of ω-3 concentrates. The free fatty acids were separated using the complexation with urea technique. The best operating conditions for separation of the fatty acids was: ratio 7:1 (urea / oil) and the crystallization temperature at -23ÂC for a time of 20 hours. After treatment of the material, the total PUFAs production was 47.87%, a ω-3 concentration of 27.59% with a saturated fraction of 4.48%. When the temperature was raised to -10ÂC, the PUFAs production was halved, reaching the value of 28.08% and 25.49% of ω-3 which was slightly altered and a saturated fraction of 42.44%. For the ester synthesis was mounted a statistical factor of two levels in order to determine the parameters which optimized the process. In the synthesis phase, the combination of temperature, glycerin concentration and catalyst was significant, and it was observed a greater influence of the glycerin concentration due to the excessive use of glycerin to favor the formation of the ester. After the analysis of the kinetic results was observed that the interactions temperature-glycerin and temperature-glycerin-catalyst were not significant (below 95%). The response interaction graphic showed the least free fatty acids index after one hour of reaction, and that the greater interaction was glycerin (5%)-catalyst (3%). It was concluded that the yields to obtain the polyunsaturated ω-3 and ω -6 from the waste of fish oil were satisfactory (85,3%). Therefore, it is concluded that it is feasible the synthesis of polyunsaturated esters of marine oils from fish waste, because this technology provides important results to avoid environmental impacts, reduce imports of fish oils and, consequently, reduce improper fishing. The aquaculture industry may be stocked with diets enriched with EPA and DHA for shrimp and fish farming, besides contributing to supply ω-3 for nutraceutical purposes.
Este trabalho teve o objetivo de desenvolver os processos de refino, alcoÃlise quÃmica seguida da separaÃÃo dos Ãcidos graxos utilizando a tÃcnica da complexaÃÃo com urÃia para a sÃntese de Ãsteres poli-insaturados a partir de resÃduos de Ãleos de pescado. O Ãleo bruto especial de peixe foi adquirido da Empresa Campestre â SÃo Paulo. Inicialmente este Ãleo sofreu um processo de refino fÃsico e quÃmico. A partir do Ãleo refinado, foi realizado um processo de alcoÃlise para se obter a mistura de Ãcidos graxos livres. Do material hidrolisado, foram obtidos 32,78% p/p de PUFAs contra 19,73% p/p de concentrados de ω-3. Os Ãcidos graxos livres foram separados utilizando-se a tÃcnica da complexaÃÃo com urÃia. As melhores condiÃÃes operacionais para separaÃÃo dos Ãcidos graxos foram: a relaÃÃo 7:1 (urÃia/Ãleo) e a temperatura de cristalizaÃÃo a -23ÂC por um tempo de 20 horas. ApÃs o tratamento do material, a produÃÃo total de PUFAs foi de 47,87%, uma concentraÃÃo de ω-3 de 27,59% com uma fraÃÃo saturada de 4,48%. Quando se elevou a temperatura para -10ÂC, a produÃÃo de PUFAs reduziu pela metade, atingindo o valor de 28,08% e 25,49% de ω-3, que pouco foi alterada e uma fraÃÃo de saturados de 42,44%. Para a sÃntese do Ãster de glicerina foi montado um fatorial estatÃstico de dois nÃveis a fim de se determinar os parÃmetros que otimizaram o processo. Na fase de sÃntese, a conjugaÃÃo de temperatura, concentraÃÃo de glicerina e catalisador foram significantes, tendo sido observado uma maior influÃncia da concentraÃÃo de glicerina, em virtude do uso excessivo de glicerina para favorecer a formaÃÃo do Ãster. ApÃs as anÃlises dos resultados cinÃticos, foi observado que as interaÃÃes temperatura-glicerina e temperatura-glicerina-catalisador nÃo foram significantes (abaixo de 95%). O grÃfico da interaÃÃo para resposta mostrou o menor Ãndice de Ãcidos graxos livres apÃs uma hora de reaÃÃo, e que a maior interaÃÃo foi glicerina (5%)-catalisador (3%). Foi concluÃdo que os rendimentos para obtenÃÃo dos poli-insaturados ω-3 e ω -6 dos resÃduos de Ãleo de pescado foram satisfatÃrios (85,3%). Conclui-se, portanto, que à viÃvel a sÃntese de Ãsteres poli-insaturados de Ãleos marinhos a partir de rejeitos de pescados, pois esta tecnologia proporciona resultados importantes para evitar impactos ambientais, diminuir as importaÃÃes de Ãleos de peixe e, consequentemente, reduzir a pesca indevida. O setor aquÃcola poderà ser abastecido com raÃÃes enriquecidas com EPA e DHA para camarÃes e peixes de cultivo, alÃm de contribuir para oferta de ω-3 para fins nutracÃuticos.
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Fazio, Chiara <1985>. "Possible Chemopreventive Role Of Eicosapentaenoic Acid In An In Vitro Model Of Inflammatory-Driven Colorectal Cancer." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7452/.
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The Notch1 signaling pathway has a pivotal role in cell fate regulation and has been found to be critically deranged in different cancers, including colorectal cancer (CRC). Inflammation is known to play an important role in the pathogenesis of CRC and a prominent function of Notch1 during inflammation has been recently demonstrated. Epithelial to Mesenchymal Transition (EMT), a crucial process in the malignant transformation, is modulated by inflammation and Metalloproteinase-9 (MMP9) is involved in this interaction. Eicosapentaenoic Acid is an omega-3 polyunsaturated fatty acid (omega-3 PUFA) known for its anti-inflammatory properties as well as for its capability in preventing colon cancer development both in sporadic and in hereditary settings. In particular, our group has demonstrated that an extra-pure formulation of Eicosapentaenoic Acid as the free fatty acid (EPA-FFA) protects from CRC development in a mouse model of colitis-associated cancer (CAC) by modulating the Notch signaling pathway. In the present work, we re-created an in vitro model of inflammatory-driven CRC by exposing colon cancer cells to a cytokine-enriched conditioned medium (CM) obtained from THP-1-differentiated macrophages. We found, for the first time, that CM strongly induces Notch1 signaling and EMT markers, increasing the capability of cells to invade. Importantly we found that, upon CM exposure, Notch1 signaling is dependent on MMP9 expression. Finally, we show that a non-cytotoxic pre-treatment with 50 μM of EPA-FFA for 72h counteracts the effect of inflammation on Notch1 signaling and EMT, leading to a reduction of invasiveness. Taken together, our data demonstrate that in CRC inflammation up-regulates Notch1 signaling through MMP9 and that this mechanism can be effectively counteracted by EPA-FFA.
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Sugiura, Miwa. "Effects of eicosapentaenoic acid-containing phospholipids on the formation of membrane proteins from Shewanella livingstonensis Ac10." Kyoto University, 2018. http://hdl.handle.net/2433/235099.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第21379号
農博第2303号
新制||農||1071(附属図書館)
学位論文||H30||N5152(農学部図書室)
京都大学大学院農学研究科応用生命科学専攻
(主査)教授 栗原 達夫, 教授 植田 充美, 教授 小川 順
学位規則第4条第1項該当
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Woisard, Kevin Keith. "Mixotrophic Production of Omega-3 Fatty Acid-rich Alga Phaeodactylum tricornutum on Biodiesel-derived Crude Glycerol." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/76902.
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Crude glycerol is the major byproduct of the biodiesel industry. There is an abundance of this byproduct and purifying it for use in industries such as food, pharmaceutical, or cosmetic is prohibitively expensive. Developing an alternative use for crude glycerol is needed. Utilizing it as a carbon source in the fermentation of algae is one potential method for using this under-utilized byproduct.
In this research, crude glycerol is used in the mixotrophic production of the alga, Phaeodactylum tricornutum, which is an eicosapentaenoic acid (EPA) producing diatom. Mixotrophic growth is when cells perform autotrophic and heterotrophic modes of growth concurrently. EPA is an omega-3 polyunsaturated fatty acid that has been demonstrated to have a multitude of beneficial health effects, including maintaining human cardiovascular health, treating cancer and human depression diseases, and an anti-obesity effect.
In this study, the potential of using crude glycerol in batch mode mixotrophic culture of P. tricornutum was investigated. Once the mixotrophic culture was established, parameters involved in increasing the biomass and EPA production were optimized. These included nitrogen source, level of supplemental carbon dioxide, and concentration of crude glycerol. Using nitrate, 0.08 M crude glycerol, and 3% (vol/vol) carbon dioxide led to the highest biomass productivity of 0.446 g L?? day?? and the highest EPA productivity of 16.9 mg L?? day?? in batch mode culture.
The continuous culture of the mixotrophic culture was then performed following the batch culture optimization. The effects of dilution rate were observed in continuous culture with the parameters of nitrate as the nitrogen source, 0.08 M crude glycerol, and 3% (vol/vol) carbon dioxide held constant. The highest biomass productivity of 0.612 g L?? day?? was obtained at D = 0.24 day??. The highest EPA productivity of 16.5 mg L?? day?? was achieved at both D = 0.15 day?? and D = 0.24 day??. The maximum specific growth rate was estimated from the washing out dilution rate and was determined to be around 0.677 day??.
Overall, it was found that crude glycerol increases the biomass and EPA productivity of Phaeodactylum tricornutum. Continuous culture with the use of crude glycerol can further increase these measurements. The potential for scaling up studies is demonstrated by these results and can help lead to a market for this abundant, little-used byproduct of the biodiesel industry.Master of Science
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Fyfe, Daren John. "Studies of the cytotoxic and cytostatic effects of eicosapentaenoic acid towards human colon cancer cells in vitro." Thesis, University of East Anglia, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320834.
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Michel, Lisa. "Studies to determine the mechanisms of the anti-atherosclerotic effects of eicosapentaenoic acid : possible role for endocannabinoids?" Thesis, Robert Gordon University, 2012. http://hdl.handle.net/10059/737.
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The ω-3 polyunsaturated fatty acids (ω-3 PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been shown to have cardioprotective and antiatherosclerotic actions. While it has been proposed that ω-3 PUFAs may structurally stabilise atherosclerotic lesions, the underlying mechanisms have yet to be fully elucidated. There is evidence that increased dietary intake of ω-3 PUFAs alters the concentration of endocannabinoids (ECs) in central and peripheral tissues and, since synthetic cannabinoid agonists have been shown to exert anti-atherosclerotic effects, this thesis explored whether a link exists between the endocannabinoid system and the beneficial effects of ω-3 PUFAs in the setting of experimental atherosclerosis. Therefore, the present studies were performed to (1) determine the impact of long-term intervention with ω-3 PUFAs on several physiological parameters, including the function of the endocannabinoid system, in an in vivo model of hypercholesterolaemia and (2) to examine the role, if any, of the activated endocannabinoid system in the activity of an in vitro model of macrophage lipid accumulation. At the cellular level, the present study demonstrated the interference of cannabinoid receptor signalling with intracellular uptake and accumulation of DHA, an effect which was demonstrated to be mediated, at least in part, via CB2 receptor signalling. Moreover, the study provided the novel observation that DHA treatment of activated macrophages significantly inhibited 2- arachidonoylglycerol (2-AG) synthesis. This finding is strongly suggestive of an association between the effects of ω-3 PUFAs and regulation of the endocannabinoid system and its function. In the ApoE-/- mouse model of experimental atherosclerosis, maintenance on an atherogenic diet induced significant hyperlipidaemia, an effect which was associated with endothelial dysfunction, cardiac remodelling, and significantly elevated anandamide (AEA) and 2-AG levels in brain, heart and aortic tissues. Supplementation of the atherogenic diet with the EPA, while having a negligible impact on endothelial dysfunction or cardiac remodelling, improved the hypercholesterolaemic profile and normalised the overproduction of ECs in both central (brain) and peripheral (heart and vascular) tissues. Fenofibrate, a lipid lowering control administered as a supplement to the atherogenic diet, was observed to significantly attenuate hypercholesterolaemia, endothelial dysfunction and elevated EC levels although no effect on cardiac remodelling was observed. In light of the observation that hypercholesterolaemia was associated with elevated tissue EC levels, together with the demonstration that EPA improved hypercholeseterolaemia and attenuated EC levels suggests (1) a detrimental role of the endocannabinoid system in hypercholesterolaemia in the ApoE-/- model and (2) regulation of this interaction by ω-3 PUFAs. Given the mounting evidence implicating the endocannabinoid system in various disease pathologies, the capacity of ω-3 PUFAs to influence the activation and function of this system may prove key to their beneficial effects.
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Cockbain, Andrew James. "The effect of eicosapentaenoic acid on biomarkers of growth and vascularity of human colorectal cancer liver metastases." Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/5903/.
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Background: The omega-3 fatty acid eicosapentaenoic acid (EPA) has been demonstrated to be incorporated into tumours and inhibit tumour growth in pre-clinical models of colorectal cancer liver metastases (CRCLM). Aims: To test the safety, tolerability and effect on tumour biomarkers of growth and vascularity of orally administered EPA in patients awaiting liver resection surgery for CRCLM. Methods: In a Phase II randomised, double-blind, placebo-controlled trial, patients with CRCLM received EPA 2g daily (n=43) or placebo (n=45) prior to surgery. CRCLM tissue was analysed for fatty acid content, PGE2 content, proliferation index (Ki-67), apoptosis index and vascularity. Blood was collected for platelet function and monocyte NFkB binding studies, and urine for measurement of PGE-M. Supplementary in vitro endothelial cell studies investigated the effects of EPA on angiogenesis. Results: The two treatment groups were well matched for burden of disease and previous chemotherapy exposure. Mean duration of EPA treatment was 30 days (range 12-65 days). EPA was safe and well tolerated, with a small excess of diarrhoea (p=0.09), and no excess of post-operative complications. Tumours from the EPA group had a 40% higher EPA content (p<0.01), no difference in proliferation or apoptosis, and a trend to reduced vascularity. EPA treatment was associated with a 36% reduction in urinary PGE-M (p=0.03) compared to placebo, and reduced monocyte NFкB DNA binding compared to baseline (p=0.03). EPA inhibited angiogenesis in vitro. Conclusions: EPA 2g daily is safe and well-tolerated in patients with CRCLM before liver resection. EPA incorporates into CRCLMs, exhibits systemic anti-inflammatory effects, and may have anti-angiogenic activity. Phase III clinical evaluation of prolonged EPA treatment is warranted in patients with, or at risk of, CRCLM.
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Hanson, Jennifer Ann. "Omega-3 fatty acids and cognitive outcomes in soldiers deployed to combat areas." Diss., Kansas State University, 2011. http://hdl.handle.net/2097/12016.
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Doctor of PhilosophyDepartment of Human Nutrition
Mark D. Haub
Mark D. Haub
Psychological problems and human error are leading causes of death and disability among military service members. Strategies to improve the psychological health and cognitive performance of those in the military are much needed. Recent advances in neuroscience suggest that omega-3 fatty acids may play an important role in the psychological well-being of those in the military. The purpose of this research was to explore the relationship between omega-3 status and psychological outcome variables among soldiers deploying to combat. Data collection was preceded by the development and reliability testing of a novel food frequency questionnaire (FFQ) designed to capture intake from contemporary sources of omega-3 fatty acids including functional foods and supplements. Based on the instrument assessment study (Chapter 2) conducted among university students (n = 165), this FFQ appears to be a comprehensive and reliable (n = 54, ρ = 0.86, p < 0.001) instrument for measuring docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) intakes in young adults. As described in Chapter 3, intake of EPA + DHA as estimated by the FFQ was positively correlated (r = 0.39, p < 0.001) with biomarker measurements of omega-3 status. Primary data were obtained from a volunteer sample of soldiers (n = 272) scheduled for deployment to Iraq. Preliminarily analyses revealed relationships between attention deficit hyperactivity disorder (ADHD) screening scores and psychological outcome variables (Chapter 4). Primary analyses (Chapter 5) indicated intake of EPA + DHA was not significantly correlated with mood, nor were omega-3 exposure variables correlated with cognitive performance based on the required p value (< 0.001) calculated using the Bonferroni correction for multiple tests. Among participants with EPA + DHA intakes at or below the median, omega-3 HUFA was related (p < 0.002) to happiness (β = -0.46), depression (β = 0.44), and fatigue (β = 0.43). Although exploratory in nature, the results of this study suggest a relationship between omega-3 fatty acids and mood. Given the current concerns regarding the psychological health of those in the military, additional research is warranted.
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Hawcroft, Gillian, Paul M. Loadman, Andrea Belluzzi, and Mark A. Hull. "Effect of the omega-3 polyunsaturated fatty acid eicosapentaenoic acid on E-type prostaglandin synthesis and EP4 receptor signalling in human colorectal cancer cells." Neoplasia Press, 2010. http://hdl.handle.net/10454/4551.
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The omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA), in the free fatty acid (FFA) form, has been demonstrated to reduce adenoma number and size in patients with familial adenomatous polyposis. However, the mechanistic basis of the antineoplastic activity of EPA in the colorectum remains unclear. We tested the hypothesis that EPA-FFA negatively modulates synthesis of and signaling by prostaglandin (PG) E(2) in human colorectal cancer (CRC) cells. EPA-FFA induced apoptosis of cyclooxygenase (COX)-2-positive human HCA-7 CRC cells in vitro. EPA-FFA in cell culture medium was incorporated rapidly into phospholipid membranes of HCA-7 human CRC cells and acted as a substrate for COX-2, leading to reduced synthesis of PGE(2) and generation of PGE(3). Alone, PGE(3) bound and activated the PGE(2) EP4 receptor but with reduced affinity and efficacy compared with its "natural" ligand PGE(2). However, in the presence of PGE(2), PGE(3) acted as an antagonist of EP4 receptor-dependent 3',5' cyclic adenosine monophosphate induction in naturally EP4 receptor-positive LoVo human CRC cells and of resistance to apoptosis in HT-29-EP4 human CRC cells overexpressing the EP4 receptor. We conclude that EPA-FFA drives a COX-2-dependent "PGE(2)-to-PGE(3) switch" in human CRC cells and that PGE(3) acts as a partial agonist at the PGE(2) EP4 receptor.
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Coleman, Danielle Nicole. "The effects of supplementing EPA and DHA during late gestation on ewes and lambs." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1498824557998868.
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Yun, Jae-Young [Verfasser], and Rainer [Gutachter] Buchholz. "Production of the Omega-3 fatty acids Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) in Schizochytrium limacinum SR21 by a Two-stage Continuous Cultivation Process / Jae-Young Yun ; Gutachter: Rainer Buchholz." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2016. http://d-nb.info/1118850025/34.
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Apolinário, Letícia Montanholi 1988. "Ácido eicosapentanóico x deflazacorte : mecanismos de ação e comparação de efeitos no tratamento de camundongos mdx." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317761.
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Orientador: Maria Julia MarquesDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A Distrofia Muscular de Duchenne (DMD) é uma doença recessiva ligada ao cromossomo X. Os glicocorticoides são amplamente utilizados para o tratamento da DMD, entretanto os efeitos colaterais decorrente de seu uso contínuo motivam a busca por novas terapias farmacológicas. Ácidos graxos poli-insaturados têm sido empregados para o tratamento de várias doenças, exercendo seus efeitos através de mecanismos pouco conhecidos... O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital
Abstract: Duchenne Muscular Dystrophy (DMD) is an X-linked recessive disease that leads to myonecrosis and cardiorespiratory failure. Glucocorticoids are so far the choice treatment for DMD. However their side effects due to continuous use motivate the search for new therapies¿ The complete Abstract is available with the full electronic document
Mestrado
Anatomia
Mestra em Biologia Celular e Estrutural
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Yue, Yang. "The Development of a Thermodynamic Model for Antisense RNA Design and an Electro-transformation Protocol to Introduce Auxotrophic Genes for Enhancing Eicosapentaenoic Acid Yield from Pythium irregulare." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/46263.
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Eicosapentaenoic acid (EPA, C20:5, n-3) is a long chain crucial unsaturated fatty acid, essential for the regulation of critical biological functions in humans. Its benefits include the therapeutic treatment of cardiovascular disease, schizophrenia and Alzheimerâ s disease. The fungus Pythium irregulare (ATCC 10951) has great potential as a natural EPA producer. In this study, the electroporation conditions for P. irregulare were determined. The auxotrophic selectable genes ura, trp and his were respectively cloned into the plasmid pESC to construct shuttle vectors. Electroporation with 2.0kV and a 0.2cm cuvette was applied as the most effective condition for heterogeneous genes transformation. The yield and content of EPA and other components of total fatty acids (TFA) were further determined by the FAME approach with GC, as well as the analysis of biomass. The EPA content in P. irregulare with heterologous pESC-TRP vector reached 16.68 mg/g if cultured in auxotrophic medium, which showed a 52.33% increase compared to the wild-type P. irregulare. The maximum of EPA yield was 98.52 mg/L from P. irregulare containing the pESC-URA plasmid, a 32.28% increase over the wild-type. However, the maximum cell dried weight of these two organisms were respectively 6.13g/L and 5.3g/L, significantly less than the 6.80g/L of the wild-type. Not only was a feasible approach detected to electro-transform and increase the EPA yield of P. irregulare, this study also inferred that Ï -6 route was mainly involved in the EPA biosynthesis in this organism.
An antisense RNA (asRNA) thermodynamic model was developed to design new asRNA constructs capable of fine-tuning gene expression knockdown. The asRNA technology is now identified as an effective and specific method for regulating microbial gene expression at the posttranscriptional level. This is done by targeting mRNA molecules. Although the study of regulation by small RNAs is advanced in eukaryotes, the regulation of expression through artificially introducing antisense oligodeoxynucleotides into host is still being developed in prokaryotes. To study the thermodynamics of asRNA and mRNA binding, (i) the fluorescence protein genes GFP and mCherry were separately cloned into the common pUC19 vector and (ii) antisense GFP and antisense mCherry DNA fragments were randomly amplified and inserted into the constructed plasmid under the control of an additional plac promoter and terminator. The expression level of fluorescence reporter proteins was determined by plate reader in this combinatorial study. A thermodynamic model to describe the relationship between asRNA binding and observed expression level was created. The study indicates two factors that minimum binding energy of the asRNA-mRNA complex and the percentage of asRNA binding mRNA were crucial for regulating the expression level. The correlation relationship between gene expression level and binding percentage multiplied by the minimum binding energy was found to show a good correlation between the thermodynamic parameters and the observed level of gene expression. The model has the potential to predict the sequence of asRNA and the approach will ultimately be applied to cyanobacteria to increase lipids production. Here, the long-term approach is to build metabolic switches from asRNA that can turn â on/offâ various cellular programs and metabolic pathways at will in a fine-tuned manner. This will allow engineers to control metabolic activity in response to reactor conditions.Master of Science
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Caldari-Torres, Cristina. "Studies on the effects and mechanisms of action of eicosapentaenoic acid on PGF₂alpha production in cultured bovine endometrial cells." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0013130.
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Areda, Martha. "The role of omega-3 fatty acids in the treatment of schizophrenia through modification of membrane phospholipids." Thesis, Linnéuniversitetet, Institutionen för kemi och biomedicin (KOB), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-55601.
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Ever since the emergence of the hypothesis that linked the aetiology of schizophrenia with abnormal membrane phospholipids composition, an increasing number of evidences have suggested reduced membrane polyunsaturated fatty acids in patients with schizophrenia. This has led to a conduct of several studies to evaluate the efficacy of omega-3 fatty acid supplement in the modification of membrane phospholipids and treatment of schizophrenia. The two main omega-3 fatty acid classes, EPA and DHA, play a vital role in membranes. This project work reviews omega-3 fatty acid studies and summarizes their outcomes. Eight original articles (nine studies) were reviewed. Six out of nine studies measured RBC membrane fatty acids levels and all six studies reported a significant increase in EPA after EPA supplement. Two studies reported increased DHA post omega-3 fatty acid and DHA supplement, respectively. One study observed a dose-dependent increment in DHA after EPA supplement. Improved symptoms were observed in seven studies, while one study found a worsening of symptoms in patients with low baseline PUFA. Moreover, out of the six studies that evaluated the correlation between symptom change and membrane fatty acids change, three studies observed a correlation between increased EPA and symptom improvement. One study reported an increased AA associated with improved symptoms, in contrast to another study, which found a correlation between increased AA and worsened symptoms. The conclusion from this project work is that EPA supplement can increase the EPA levels in membranes; however, its therapeutic effect in schizophrenia requires further investigation using larger studies.Ända sedan tillkomsten av hypotesen som länkade etiologin av schizofreni med onormala sammansättningar av membranfosfolipider, har bevis för nedsatt membranfettsyror hos patienter med schizofreni ökat. Detta har lett till genomförandet av flera studier för att utvärdera effekten av omega-3 supplement i modifieringen av membranfosfolipider och i behandling av schizofreni. De två viktigaste omega-3 klasserna, EPA och DHA, spelar en viktig roll i membran. Detta projektarbete granskar de omega-3 studierna och sammanfattar deras resultat. Åtta originalartiklar (nio studier) granskades. Sex av nio studier mätte nivåer av RBC membranfettsyror och alla sex studierna rapporterade en signifikant ökning av EPA efter EPA behandling. Två studier rapporterade ökad DHA efter omega-3 och DHA behandling, respektive. En studie observerade en dosberoende ökning i DHA efter EPA behandling. Förbättrade symtom observerades i sju studier, medan en studie fann en försämring av symtom hos patienter med låg baseline PUFA. Av de sex studier som utvärderade sambandet mellan symtomförändring och förändring i membranfettsyror, hittade två studier samband mellan ökad EPA och symtomförbättring. En studie rapporterade en ökad AA i samband med förbättrade symtom, i motsats till en annan studie, som fann ett samband mellan ökad AA och försämrade symtom. Slutsatsen från detta projektarbete är att EPA tillägg ökar nivåer av EPA i membranfosfolipider; men dess terapeutiska effekt vid schizofreni kräver ytterligare utredning med hjälp av större studier.