Dissertations / Theses on the topic 'Sugar fatty acid ester'
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Yan, Youchun. "Enzymatic production of sugar fatty acid esters." [S.l. : s.n.], 2001. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB9102241.
Full textAdamopoulos, Lambrini. "Understanding the formation of sugar fatty acid esters." NCSU, 2006. http://www.lib.ncsu.edu/theses/available/etd-06272006-002917/.
Full textAVRAMIDOU, KALLIOPI. "BIOCATALYSIS FOR BIOMASS VALORIZATION: PROTEIN HYDROLYSATES AND SUGAR ESTERS FROM AGRI-FOOD WASTES." Doctoral thesis, Università degli Studi di Milano, 2020. http://hdl.handle.net/2434/704558.
Full textFerreira, Gicelia Antonia. "Identificação de líquidos iônicos próticos como solventes para aplicações em biocatálise." Escola Politécnica, 2016. http://repositorio.ufba.br/ri/handle/ri/22632.
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CAPES, FAPESB
Nos dias atuais, há um grande e crescente interesse em encontrar substâncias ambientalmente amigáveis para processos industriais. Os líquidos iônicos são candidatos a substituir os solventes orgânicos convencionais reduzindo a quantidade de resíduos e diminuindo o impacto ambiental; à temperatura ambiente, esses materiais praticamente não possuem pressão de vapor, são não inflamáveis, podendo ser sintetizados de modo específico, através da combinação diferencial entre cátions e ânions, para desempenhar o papel necessário, além de serem facilmente recicláveis. Os líquidos iônicos são novos meios promissores para muitos processos, tais como síntese química, reações enzimáticas e aplicações no setor de “engenharia verde”. O interesse pela classe dos líquidos iônicos próticos justifica-se em decorrência da sua síntese simples, do baixo custo produção, da baixa toxicidade e da biodegradabilidade, os quais são aspectos inerentes aos processos “verdes”. Nesse contexto, ressalta-se a aplicação dos líquidos iônicos próticos na síntese enzimática de ésteres graxos de açúcares. Cumpre destacar que os mesmos podem ser sintetizados quimicamente ou enzimaticamente. A síntese química diverge da tendência atual, na qual o foco está voltado para a utilização de tecnologias sustentáveis e ambientalmente seguras. Por outro lado, a síntese enzimática é realizada em condições mais suaves de reação, apresenta elevada seletividade e especificidade, o que facilita a recuperação do produto. Porém, a síntese enzimática de ésteres graxos de açúcares encontra um obstáculo, uma vez que os solventes orgânicos capazes de solubilizar adequadamente os carboidratos também agem de forma negativa sobre as enzimas, inativando-as. Portanto, no presente trabalho foi investigado um conjunto de líquidos iônicos próticos visando identificar um meio de reação apropriado para o processo enzimático de síntese do oleato de galactose, que atenda às condições de maximizar a solubilização do carboidrato. Para tanto, uma gama de líquidos iônicos próticos foram sintetizados e caracterizados em termos de coeficiente de partição, viscosidade e solubilidade da galactose, pois essas propriedades exercem influência direta sobre a ação enzimática. Até o melhor de nosso conhecimento, este é o primeiro estudo com foco no processo de produção enzimática de ésteres graxos de açúcares na presença de líquidos iônicos próticos.
Nowadays, there is a great and growing interest in environmentally friendly substances for industrial processes. Ionic liquids are candidates to replace the conventional organic solvents decreasing the amount of waste and reducing the environmental impact; at room temperature, ionic liquids have practically no vapor pressure, are not flammable and may be synthesized specifically through the differential combination of cations and anions, in order to perform the role needed, and are easily recyclable. Ionic liquids are new promising media for many processes, such as chemical synthesis, enzymatic reactions and applications in the “green engineering” sector. The interest for the class of protic ionic liquids is justified due to their simple synthesis, low cost of production, low toxicity and biodegradability potential, which are aspects inherent to the “green” processes. In this context, we highlight the application of protic ionic liquids in the enzymatic synthesis of fatty esters of sugars. It is worth noting that the same can be synthesized chemically or enzymatically. The chemical synthesis diverges from the current trend, in which the focus has turned to the use of sustainable and environmentally safe technologies. On the other hand, the enzymatic synthesis is performed under milder reaction conditions, presents high selectivity and high specificity, besides product recovery ease. Nevertheless, the enzymatic synthesis of fatty esters of sugars meets an obstacle, because the organic solvents able to adequately solubilize the carbohydrate also act negatively on the enzymes, inactivating them. Therefore, in the present study was proposed to investigate a class of protic ionic liquids in order to identify an appropriate reaction medium to the enzymatic process of synthesis of galactose oleate, which meets the conditions of maximizing the solubilization of the carbohydrate. For that, a range of protic ionic liquids were synthesized and characterized in terms of partition coefficient, viscosity and solubility of galactose, because these properties directly influence the enzymatic action. To the best of our knowledge, this is the first study focusing on the enzymatic production process of fatty esters of sugars in the presence of protic ionic liquids.
Fregapane, Giuseppe. "Chemo-enzymatic synthesis of sugar fatty acid ethers." Thesis, University of Reading, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357150.
Full textŠinkūnienė, Dovilė. "Lipase selection and application for fatty acid ester synthesis." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140210_082745-97488.
Full textLipazių atranka ir taikymas riebalų rūgščių esterių sintezei Lipazės yra intensyviai tiriama fermentų grupė dėl jų gebos katalizuoti platų spektrą sintezės reakcijų. Disertacinio darbo tikslas buvo ištirti ir optimizuoti riebalų rūgščių esterių sintezės, panaudojant lipazes, būdus. Tirta fermento preparato paruošimo (imobilizavimo), fermento bei substratų pasirinkimo bei reakcijos sąlygų ir priedų įtaka riebalų hidrolizės, biodyzelino, fenetiloktanoato (kvapiojo esterio) sintezės reakcijų eigai ir išeigai. Pirmą kartą ištirtos Lietuvoje paruoštos Enterobacter aerogenes lipazės savybės, ji imobilizuota ant gamtinės kilmės nešiklių. Komercinių lipazių katalizuojamų reakcijų sąlygų įtakai nustatyti ir reakcijos išeigai optimizuoti naudota atsako paviršiaus metodologija. Tiriant reakcijos priedų įtaką acilgrupės migracijai ir biodyzelino sintezės reakcijai, nustatyta, kad perspektyvus priedas yra silikagelis. Lipazių specifiškumas ženkliai skiriasi skirtingoms acilglicerolių klasėms ir regioizomerams, šių žinių pagrindu buvo pasiūlyta dviejų etapų biodyzelino sintezės katalizė.
Pisac, Claudia A. "An experimental study of combustion characteristics of fatty acid methyl ester biodiesel." Thesis, University of Hertfordshire, 2014. http://hdl.handle.net/2299/14641.
Full textDe, Castro Ana Maria. "Fatty acid methyl ester analysis of microbial communities in biofilters inoculated with different sources." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ28820.pdf.
Full textHikosaka, Tomoyuki, Yasunori Hatta, Hidenobu Koide, Akina Yamazaki, Fumihiro Endo, Hitoshi Okubo, Tsutomu Nara, and Katsumi Kato. "Space Charge Behavior in Palm Oil Fatty Acid Ester (PFAE) by Electro-optic Field Measurement." IEEE, 2009. http://hdl.handle.net/2237/14538.
Full textBollin, Patrick M. "The Production of Fatty Acid Methyl Esters in Lewis Acidic Ionic Liquids." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1321507054.
Full textKadisch, Marvin [Verfasser]. "Stabilizing whole-cell biocatalysts : En route to more efficient fatty acid methyl ester bioprocessing / Marvin Kadisch." Aachen : Shaker, 2017. http://d-nb.info/1149269103/34.
Full textKoide, Hidenobu, Keizo Kawanishi, Katsumi Kato, Hitoshi Okubo, Naoki Hayakawa, and Hiroki Kojima. "Charge behavior in Palm Fatty Acid Ester Oil (PFAE) / pressboard composite insulation system under voltage application." IEEE, 2012. http://hdl.handle.net/2237/20736.
Full textBanerjee, Sagarika. "EFFECTS OF LIVESTOCK ANTIBIOTICS ON NITRIFICATION, DENITRIFICATION, AND MICROBIAL COMMUNITY COMPOSITON IN SOILS ALONG A TOPOGRAPHIC GRADIENT." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_theses/43.
Full textBahceci, Humeyra. "Fatty Acid Methyl Ester Analysis Of Bacterial Isolates From Salt Lake, Turkey And Characterization Of Their Extracellular Enzymes." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/3/12605483/index.pdf.
Full text#945
-amylase and protease. These enzymes were characterized in terms of enzyme activity, stability, optimum temperature and optimum pH. One of the isolates was identified as Bacillus pumilus, and two of them were identified as Bacillus subtilis. Other isolates were determined to be Bacillus licheniformis. All the isolates were determined to produce xylanase. Optimum temperatures and optimum pH values of xylanases were 50-55 °
C and pH 7.0-8.0. Xylanases were quite stable up to pH 8.0 and 70 °
C. Isolates were not significant cellulase producers. Four of the isolates did not produce any cellulase enzyme and the rest produced negligible amounts of cellulase. Therefore, xylanases from the isolates were promising for pulp and paper industry, which requires cellulase free and stable xylanases. All the isolates produced appreciable quantities of &
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-amylase. Optimum temperatures and optimum pH values of &
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-amylases 60-80 °
C and pH 7.0-8.0. &
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-Amylases were quite stable up to pH 9.0 and 80 °
C. &
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-Amylases from the isolates were promising for starch processing industry, which requires &
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-amylases stable at high temperatures and for detergent industry, which requires &
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-amylases stable at alkaline pH values. Considerable protease productions were achieved by all the isolates. TTG 2 was the best protease producer with 271 U/ml. Optimum temperatures and optimum pH values of proteases were 50-60 °
C and pH 7.0-7.4. Proteases were quite stable up to pH 9.0 and 80 °
C. Proteases from the isolates were promising for detergent and leather industry, in which proteases must be stable at alkaline pH values.
Koide, H., T. Hikosaka, Y. Hatta, A. Yamazaki, F. Endo, K. Kato, T. Nara, S. Yamamoto, and H. Okubo. "Charge Behavior in Palm Fatty Acid Ester Oil (PFAE) / Pressboard Insulation System under Flow Condition in Power Transformers." IEEE, 2008. http://hdl.handle.net/2237/12075.
Full textStarr, Christopher Daniel. "Fatty acid derived ester related gene expression, activities, and volatiles for on-tree ripening and storage of apples." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Fall2009/c_starr_091409.pdf.
Full textTitle from PDF title page (viewed on Jan. 8, 2010). "Program in Molecular Plant Sciences." Includes bibliographical references (p. 61-68).
Grayson, John David. "Improvement of Yellow Perch Larvae Culture via Live Food Enrichment with Polyunsaturated Fatty Acids." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1417720966.
Full textMaios, Claudia. "Expression of defence-related genes in sugar beet plants infected with Rhizoctonia solani and treated with benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH)." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99349.
Full textWestberg, Emilie. "Qualitative and Quantitative Analysis of Biodiesel Deposits Formed on a Hot Metal Surface." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-95617.
Full textTestud, Blandine. "Les huiles végétales comme plateforme pour la conception de nouveaux polyesters hyper-ramifiés." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0365/document.
Full textThe aim of this thesis was to use vegetable oils as a platform for the design of more sustainable polyesters of hyperbranched architecture. For that purpose, the approach by polycondensation of ABn-type monomers (n ≥ 2) was favored. Plant oils and/or fatty acid methyl esters were chemically modified to synthesize multifunctional precursors featuring ester (A) and alcohol moieties (B). Simple, safe and efficient chemical transformations were considered to provide industrial perspectives to this work. Two main platforms of ABn-type monomers were developed by (1) acid hydrolysis of epoxidized vegetables oils and (2) thiol-ene/metathesis coupling reactions. The subsequent polycondensation of these oily-derived monomers, performed in bulk, gave access to novel renewable hyperbranched polyesters. The branching density as well as the thermo-mechanical properties of these materials were adjusted by designing and selecting the chemical structure of the fatty acid-based monomers. Finally, an exploratory work was carried out regarding the post-functionalization of both the core and the periphery of these hyperbranched polyesters with the aim at tuning their properties and thus opening the scope of their applications, from commodity plastics to advanced materials
Lancaster, Sarah Renee. "Soil microbial response to glyphosate-base cotton pest management systems." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2636.
Full textSaleh, Jehad. "A Membrane Separation Process for Biodiesel Purification." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19730.
Full textRudolph, Tim Christoph [Verfasser], Lothar [Akademischer Betreuer] Mörl, Waltraud [Akademischer Betreuer] Kahle, and Gerald [Akademischer Betreuer] Warnecke. "Model-based stochastic optimization of palm oil deodorization via Short-Path-Distillation towards 3-MCPD fatty acid ester formation and major oil quality parameters / Tim Christoph Rudolph ; Lothar Mörl, Waltraud Kahle, Gerald Warnecke." Magdeburg : Universitätsbibliothek, 2016. http://d-nb.info/1125507993/34.
Full textRudolph, Tim Christoph Verfasser], Lothar [Akademischer Betreuer] [Mörl, Waltraud [Akademischer Betreuer] Kahle, and Gerald [Akademischer Betreuer] Warnecke. "Model-based stochastic optimization of palm oil deodorization via Short-Path-Distillation towards 3-MCPD fatty acid ester formation and major oil quality parameters / Tim Christoph Rudolph ; Lothar Mörl, Waltraud Kahle, Gerald Warnecke." Magdeburg : Universitätsbibliothek, 2016. http://d-nb.info/1125507993/34.
Full textNguyen, van Cuong. "Maîtrise de l'aptitude technologique des oléagineux par modification structurelle : applications aux opérations d'extraction et de transestérification in-situ." Thesis, La Rochelle, 2010. http://www.theses.fr/2010LAROS308/document.
Full textThe present work has concerned the impact of Instant - Controlled Pressure Drop (DIC) texturing on both operations of oil extraction and in-situ transesterification, carried out with the rapeseed and the kernels of Jatropha Curcas. A fundamental analysis proved the importance of the reactive or solvent diffusion within the solid matrix. By texturing the natural product, the whole operation can be intensified. The process is revealed through three characteristics, which are the effective diffusivity, the starting accessibility, and the yields of extraction. Also, the kinetics and yield of fatty acid methyl ester of in-situ transesterification are discovered. A phenomenological study allowed determining the value of these characteristics versus DIC operating parameters (saturated steam pressure P and treatment time t).A 2 h solvent extraction of DIC treated material allowed the total oil yields to be improved by 153% for colza and 112% for jatropha, the effective diffusivity (Deff) can reach up to 8.014*10-12 m2/s as against 0.715*10-12 m2/s for colza untreated by DIC, and up to 5.90*10-12 m2/s as against 2.42*10-12 m2/s for the untreated jatropha. The rate of initial accessibility of products treated by DIC can reach up to 80.53% as against 26.71% for untreated colza and can reach up to 92.58% as against 75.91% for the product untreated jatropha. In the case of in situ transesterification, the total yield of fatty acid methyl esters (FAME total) obtained from the DIC treated products is systematically higher than that of untreated colza and jatropha raw material. The reaction time was decreased to 30 - 45 min instead of 120 min in the case of colza, and to 15 min instead of 60 min in the case of jatropha kernel
Sangaletti, Naiane. "Transesterificação química e enzimática de miscela etanólica de óleo de soja." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-24092012-162906/.
Full textThe feedstock for biodiesel production represents more than 70% of the cost and technological and economic feasibility studies of different oil sources are of enormous importance. The extraction of soybean oil with ethanol solvent results in two miscella, one rich in oil (rich miscellae) and another rich in ethanol (poor miscellae). The poor miscellae can be reused in the extraction process and the rich miscellae can be used directly without dessolventizing and refining stages. The oil rich miscellae was esterified by two different processes: chemical and enzymatic, with different concentrations in the molar ratio (oil: ethanol), different temperatures and either basic catalyst (NaOH) or an enzyme (Novozym®435), searching for the highest production of ethyl esters. The study goal was to prove the feasibility of producing biodiesel from the transesterification of rich miscellae (oilethanol) in soybean oil, without oil refining and evaluating the performance of ethyl esters by applying immobilized enzymes Novozym®435 and a basic catalyst (NaOH). We adopted the experimental design and the surface response methodology for the best selection of process conditions, with the response variables the yield and the quality of biodiesel. Chemical and enzymatic esterification trials were conducted. The reuse of enzyme was studied by washing with different solvents (96% ethanol, isopropanol and tert-butanol) and the transesterification reaction in the presence of the co-solvent tert-butanol. The production of esters by enzymes in the miscellae allowed a comparison of the costs between the enzymatic and chemical catalysis process based on the energy flow analysis. The rich miscellae was obtained after three baths employing the poor miscellae and a last fourth bath with ethanol 99% (v/v), presenting efficiency of 83% and a residual meal oil content of 4.2%. In its composition, the rich miscellae showed 90% of soybean oil and up to 7% ethanol. The transesterification of the rich miscellae with NaOH catalyst was optimized and had a ethyl esters yield (RE) of 97.2% under the experimental conditions of: 1:12 molar ratio, catalyst concentration 0.67% and temperature 30° C. For the enzymatic transesterification, the maximum yield was 85% for the reaction conditions: molar ratio 1:4.5, catalyst concentration 9.5% and temperature 40° C. Novozym®435 was not recovered with successive washes of the solvents. However, the tertbutanol as a co-solvent increased the yield of esters to 94%. The energy flow analysis showed that obtaining the raw material (flaking and extraction) was the most energy demanding. The rich miscellae from the semi-pilot plant demanded more energy than the refined oil, however, the transesterification of the rich miscellae using chemical catalyst, required less energy compared to the enzymatic catalysis and the conventional process methanol and ethanol. The esterification of rich miscellae is feasible energetically, however, the extraction step with ethanol should be adjusted to enable energetically the chain of biodiesel production.
Pourkhesalian, Ali Mohammad. "Effects of biodiesel chemical composition on the chemical and physical properties of the primary and secondary diesel particulate matter." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/86757/14/86757_Ali_Mohammad_Pourkhesalian_Thesis.pdf.
Full textSporkert, Frank. "Anwendungen der Headspace-Festphasenmikroextraktion in der forensischen Analytik unter besonderer Berücksichtigung der Haaranalyse." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2001. http://dx.doi.org/10.18452/14698.
Full textIn the presented thesis possible fields of applications of the headspace solid-phase microextraction (HS-SPME) in combination with gas chromatography-mass spectrometry (GC-MS) for forensic and toxicological problems were investigated with special focus on hair analysis. Detection methods after alkaline hydrolysis of hair with sodium hydroxid and following HS-SPME were developed for basic stable drugs. For the local anaesthetic lidocaine and for the heroine substitute methadone optimized methods were applied to hair of drug fatalities. In order to enhance the fields of application of the HS-SPME especially for drug metabolites three derivatization procedures were tested: (i) conversion of primary and secondary amines in the alkaline hair extract with alkylchloroformates to carbamates ("in sample" derivatization), (ii) "on fibre" derivatization of primary and secondary amines after HS-SPME with N-methyl-bis-trifluoroacetamide (MBTFA) and (iii) reaction of monofluoroacetic acid (compound 1080) with 1-pyrenyldiazomethane (PDAM) on a SPME-fibre previously occupied with the derivatization reagent. Fatty acid ethyl ester (FAEE) could detected after liquid extraction from hair of alcoholics with a mixture of DMSO/n-hexane and optimized HS-SPME. In comparison to hair samples of teetotalers and social drinkers significant differences in the concentrations of the FAEE were found. A quantification method were developed for the fast determination of valproic acid and trichloroethanol from blood and urine. The application of HS-SPME allows a fast, simple and solvent free extraction from a small sample amount. HS-SPME lead to clean extracts and high absolute extraction yields for this kind of extraction. Better reproducibilities, a high sample throughput and extended lifetime of the SPME-fibre were obtained using an automatic sampler.
Mayer, Júlia Gonçalves. "Comparação da análise de ácidos graxos TRANS em biscoito por cromatografia gasosa acoplada a espectrometria de massas (cg-em) e por espectroscopia no infravermelho com transformada de fourier e reflectância total atenuada (FT-IR-ATR)." Niterói, 2018. https://app.uff.br/riuff/handle/1/5892.
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Os métodos analíticos utilizados para medir o percentual de ácido graxo trans (AGT) em alimentos envolvem cromatografia em fase gasosa com detecção de ionização de chama (CG-DIC), espectrometria de massas (CG-EM) e espectroscopia no infravermelho com transformada de Fourier e refletância total atenuada (FT-IR-ATR). O presente estudo teve como objetivo investigar a viabilidade e a aplicabilidade do uso das técnicas de FT-IR-ATR, sem extração, com extração prévia da gordura e após hidrólise e metilação dos ácidos graxos, para avaliar o conteúdo de AGT em biscoitos recheados e comparar os resultados obtidos com os encontrados para a determinação de ácido elaídico pela técnica de CG-EM. Foram escolhidas 9 marcas de biscoitos recheados sabor chocolate e 1 pacote de gordura vegetal hidrogenada, para ser usada como padrão secundário para análise de AGT por FT-IR-ATR. As amostras foram analisadas, inicialmente, quanto aos seus conteúdos de umidade e lipídeos totais. Para todas as amostras não foi observada concentração de umidade superior a 6,03 g/100 g. Os lipídeos totais variaram de 12,51±0,58 a 23,84±0,09 g/100 g. A presença de AGT foi identificada por FT-IR-ATR pela visualização da banda próxima a 966 cm−1 e confirmada com adição de padrão às amostras. Ao analisar as amostras de biscoito homogeneizadas e sem outro preparo, não foi viável a utilização do método de FT-IR-ATR, visto que a absorção de radiação infravermelha de substâncias da amostra se sobrepõe à absorção na região das ligações duplas trans, o que demonstra que a matriz do alimento pode influenciar na análise. Quanto a presença dos AGT, ácido elaídico (C18:1, n-9 trans) foi identificado e confirmado em todas as amostras através de CG-EM. Ao comparar a quantificação pelos métodos CG-EM e FT-IR-ATR em amostras de extratos e na forma de ácidos graxos metilados (FAME), foram observadas concentrações baixas de ácido elaídico/ácidos graxos trans (de 0,03±0,01 a 0,86±0,01 g/100 g de biscoito) obtidas pelos diferentes métodos. Não foram encontradas diferenças significativas entre as concentrações de AGT determinadas pelos três métodos testados para oito das nove amostras analisadas. O presente trabalho mostrou que a técnica de FT-IR-ATR, analisando o extrato lipídico e as amostras em forma de FAME foi adequado para estimar os teores de AGT em biscoito recheado de chocolate, visto que proporciona uma análise mais rápida, com um menor número de etapas e menor consumo de reagentes em relação às análises por CG-EM
The analytical methods used to measure the percentage of trans fatty acids in foods involve gas chromatography with flame ionization detection (GC-FID), mass spectrometry (GC-MS) and attenuated total reflectance fourier transform infrared spectroscopy (ATR-FT-IR). The aim of the present study was to investigate the feasibility and applicability of ATR-FT-IR techniques, without extraction, with previous extraction of fat and after hydrolysis and methylation of fatty acids to evaluate the content of TFA in filled biscuits, and compare the results obtained with those found for the determination of elaidic acid by the CG-MS technique. Were chosen 9 marks of chocolate filled biscuit and 1 packet of hydrogenated vegetable fat to be used as a secondary standard for AGT analysis by ATR-FT-IR. The samples were initially analyzed for their moisture contents and total lipids. For all samples, no moisture content higher than 6.03 g/100 g. Total lipids ranged from 12.51 ± 0.58 to 23.84 ± 0.09 g/100g. The presence of TFA was identified by ATR-FT-IR through the visualization of the band near 966 cm−1 and confirmed with addition of standard to the samples. When analyzing the homogenized cookie samples and without further preparation, the use of the ATR-FT-IR method was not feasible because the absorption of infrared radiation from sample substances overlaps the absorption in the region of the trans double bonds, which demonstrates that the food matrix may influence the analysis. Regarding the presence of TFA, elaidic acid (C18: 1, n-9 trans) was identified and confirmed in all samples by GC-MS. When comparing quantification by GC-MS and ATR-FT-IR in samples of extracts and in the form of fatty acids methly esters (FAME), low concentrations of elaidic acid / trans fatty acids were observed (0.03 ± 0.01 to 0.86 ± 0.01 g / 100 g of biscuit) obtained by the different methods. No significant differences were found between the concentrations of TFA determined by the three methods tested for eight of the nine samples analyzed. The present study showed that the ATR-FT-IR technique, analyzing the lipid extract and the samples in the form of FAME, was adequate to estimate the TFA contents in chocolate filled biscuit, because it provides a faster analysis with a smaller number of steps and lower toxic chemicals in relation to GC-MS analyzes
Auwärter, Volker. "Fettsäureethylester als Marker exzessiven Alkoholkonsums." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2006. http://dx.doi.org/10.18452/15421.
Full textThe current doctoral thesis presents the development of an analytical procedure for the quantitative analysis of fatty acid ethyl esters (FAEE) in hair and in skin surface lipids using headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) as well as a method based on high-performance liquid chromatography with photodiode array detection (HPLC-DAD) to determine squalene concentrations in lipid extracts. The results obtained from analysis of samples from different alcohol consuming groups showed that FAEE are suitable markers for long-term alcohol misuse. Concerning sensitivity and specifity they are at least as good as other commonly used markers like GGT, CDT or MCV. The following provisional cut-off values were established: for chronically excessive alcohol consumption, the sum of the four FAEE (ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate) found in the highest mean concentrations should be > 1 ng/mg in hair; for non-drinkers, concentrations < 0,4 ng/mg are typical. The quotient obtained by dividing the FAEE concentration by the squalene concentration was defined as the relative FAEE concentration, which provides a better classification of the samples regarding the consumer groups through hair analysis. Relative FAEE values also allow a reasonable comparison in the case of skin surface lipid concentrations for the first time. 2 ng/µg is suggested as a preliminary cut-off value. As a further important result of the current work, the mechanism of incorporation of FAEE into hair was clarified. It was shown that fatty acid ethyl esters are incorporated into hair mainly through sebum.
Falahati, Hamid. "The Characterization of Bimodal Droplet Size Distributions in the Ultrafiltration of Highly Concentrated Emulsions Applied to the Production of Biodiesel." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/19585.
Full textNatural Sciences and Engineering Research Council of Canada (NSERC)
SERRE, ISABELLE. "Comportement d'une serie d'esters de l'acide oleique sur cuticules vegetales et effets sur la penetration foliaire d'herbicides." Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10244.
Full textCai, Xiaoshuang. "Production of carbonated vegetable oils from a kinetic modeling to a structure-reactivity approach Structure-reactivity : comparison between the carbonation of epoxidized vegetable oils and the corresponding epoxidized fatty acid methyl ester Aminolysis of cyclic-carbonate vegetable oils as a non-isocyanate route for the synthesis of polyurethane: a kinetic and thermal study Influence of ring‐opening reactions on the kinetics of cottonseed oil epoxidation Investigation of the physicochemical properties for vegetable oils and their epoxidized and carbonated derivatives Influence of gas-liquid mass transfer on kinetic modeling : carbonation of epoxidized vegetable oils." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMIR05.
Full textNowadays, biomass and carbon dioxide valorization are considered as a helpful solution to the environmental issues of global warming and the depletion of petroleum reserves. Thus, vegetable oils have attracted increasing attention of academic and industrial communities, as one of the potential renewable biomass that can be applied to the production of fossil substitute for sustainable development, owning to their advantages of renewable, sustainable, biodegradable, and universally available with huge feedstock. Among decades of researches, epoxidation and carbonation processes are two popular application methods for vegetable oil valorization. The conversion of vegetable oils into epoxidized ones is defined by a conversion of unsaturated compound into an epoxide group. So far, the potential application for the production of epoxidized oil in the industrial is the Prileschajew oxidation, which is a wellknown conventional way to be used as the commercial production process. This type of epoxidation uses percarboxylic acid as an oxygen carrier, which is formed in situ in the aqueous phase, and then epoxidize the unsaturated groups on the vegetable oils into epoxide groups. During the process, however, this method presents side reaction of ring-opening of the epoxide group. Therefore, the selective epoxidation process conditions need to be optimized in order to minimize the ring-opening reactions. In this study, process parameters including the concentration of acid catalyst (sulfuric acid), reactants (water, epoxide group, hydrogen peroxide, acetic acid) and the reaction temperature have been discussed for the epoxidation and ring opening of vegetable oils. During the kinetic modeling stage, the related kinetic constants for the ring opening reactions were estimated. Based on this model, the ring opening by acetic and peracetic acids was found to be faster than by water and hydrogen peroxide. A semibatch reactor, where hydrogen peroxide and sulfuric acid were added, was found to be the most suitable configuration. To determine the optimum operating conditions and scale up the epoxidation or carbonation processes, it requires the database of different physicochemical properties, i.e. viscosity, density, refractive index, or specific heat capacity and the evolutions of these properties with the temperature. However, this information is absent in the literature. For this study, the evolution of these properties with temperature and compositions (double bond, epoxide and carbonated groups concentration) was determined for three vegetable oils and their corresponding epoxidized and carbonated forms (cottonseed oil, linseed oil and soybean oil). Density and refractive indices of these oils were found to vary linearly with temperature. Based on the measurement of changes in viscous stresses with shear rates, these oils were found to be Newtonian fluids. It was demonstrated that specific heat capacity follows a polynomial equation of second order with temperature. Based on these results, it was demonstrated that some correlations could be used to predict the evolutions of these physicochemical properties at different composition and temperature based on the knowledge of the property of the pure compounds
Yan, Youchun [Verfasser]. "Enzymatic production of sugar fatty acid esters / vorgelegt von Youchun Yan." 2001. http://d-nb.info/961513578/34.
Full textKumar, Nikhil. "Synthesis of Sugar Fatty Acid Esters using Lipase Immobilized in Supported Sol-Gels." Thesis, 2012. http://hdl.handle.net/10012/6617.
Full textZHANG, WEN-YAN, and 張文煙. "Discussion on Modified Plant Fatty Acid Ester Oil." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6n26g5.
Full text國立臺北科技大學
車輛工程系
107
Global environmental awareness rises and energy is shrinking. Therefore, the research on increasing the conversion rate of fuels and the research and development of fuel injection systems are the current research directions that mainly reduce fuel consumption. In this study, the engine lubrication is used to explore the fuel consumption rate by changing the engines lubricating oil. With the impact of braking the average effective pressure. In this study, CPC Heavy Duty Extra Special SJ / CD 15W-40 Motor OIL from CPC Corporation and HYPERION 6000 CF-4 5W-40 oil from LUPROMAX were used to add 80ml LUPROMAX EA oil additive for single cylinder diesel engines. The experimental results show that the average value of BSFC of Lubricant Universal HYPERION 6000 CF-4 5W-40 is higher than CPC Heavy Duty Extra Special SJ / CD 15W-40 Motor OIL produced by CPC Corporation. Based on the above experimental results, we understand that castor oil additive is a good additive that enhances engine lubrication and is worth promoting.
Strieleman, Paul J. "Fatty acid and fatty acyl CoA ester effects on brown adipose tissue mitochondria uncoupling protein ion conductance activity." 1985. http://catalog.hathitrust.org/api/volumes/oclc/13365929.html.
Full textChen, Jhih-Hong, and 陳志宏. "Effect of fatty acid methyl ester compositions of various biodiesel blends on fuel properties." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/t2jp32.
Full text國立臺北科技大學
化學工程研究所
98
The objective of this study is to blend four biodiesels including tung oil, oleic acid, palm oil, and jatropha oil methyl esterd. The fatty acid methyl esters (biodiesel) were obtained from the transesterification of animal fats and vegetable oils. Some properties of biodiesel like cold filter plugging point (CFPP), kinematic viscosity (KV), and induction period for oxidation stability (IP), etc. can not satisfy the biodiesel specification standards (ex. CNS 15072 in Taiwan), especially in the poor low-temperature properties and oxidation stability. One main cause accounting for the different properties of biodiesel comes from the different fatty acid methyl ester compositions. Therefore, this study studied the properties of biodiesel blends which were chosen from the biodiesels synthesized from various vegetable oils, including canola oil, coconut oil, jatropha oil, oleic acid, palm oil, palm kernel oil, soapnut oil, soybean oil, sunflower oil, and tung oil. The corresponding biodiesels were denoted as CME, COME, JME, OME, PME, PKME, SOME, SME, SUME, and TME, respectively. Furthermore, the properties of biodiesels such as acid value (AV), CFPP, density, iodine value (IV), KV, and IP were analyzed. Then three biodiesels showing the complementary properties are chosen to be blended in different weight ratio for the satisfaction of the biodiesel specification standards. Six blend combination were tested in this study. The optimum blending ratios are: The 1st group is 60 wt.% CME, 20 wt.% PME, and 20 wt.% TME (analytic items: CFPP, density, IV, and KV). The 2nd group is 20 wt.% COME, 20 wt.% PKME, and 60 wt.% TME (analytic items: density, IV, KV, and IP). The 3rd group is 70 wt.% OME, 30 wt.% PME, and 0 wt.% SME (analytic items: CFPP, IV, and IP). The 4th group is 60 wt.% OME, 20 wt.% PME, and 20 wt.% TME (analytic items: CFPP, density, IV, KV, and IP). The 5th group is 100 wt.% JME, 0 wt.% PME, and 0 wt.% SME (analytic items: CFPP, IV, and IP). The 6th group is 70 wt.% JME, 30 wt.% SOME, and 0 wt.% SUME (analytic items: CFPP, IV, and IP). In addition, the multiple linear regression equations were used to investigate the effects of the fatty acid compositions of biodiesel blends on the fuel properties.
LIN, YU-CHENG, and 林昱丞. "Comparison of the Properties of Vegetable Fatty Acid Ester Motor Oil and Petrochemical Motor Oil." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/vtnug2.
Full text國立臺北科技大學
車輛工程系
106
The demand for energy is increasing in the future. The development of fuel research and fuel injection system are the main research directions to reduce fuel consumption. In the present study, the engine lubricating oil was used to study the effect of engine lubrication on BSFC and BMEP. CPC Superfleet CH4 Motor Oil is from CPC Corporation and HYPERION 6000 CF-4 oil is from Lupromax, which have castor oil additive used in this study for single cylinder diesel engines. The experimental results show that the average BSFC of HYPERION 6000 CF-4 oil is less than 1.56% of the average value of CPC Superfleet CH4 Motor Oil’s BSFC, and the average BMEP of HYPERION 6000 CF-4 oil is higher than 0.11 % of the average value of CPC uperfleet CH4 Motor Oil’s BMEP. Based on the above experimental results, we understand that castor oil additive is a good additive in engine lubrication and it is worth promoting.
Luo, Wan-jhen, and 羅琬真. "Liquid-Liquid Equilibrium for Ternary Mixtures Containing Water, Methanol, Fatty Acid Methyl Ester, Glycerol or Sulfolane." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/50578695612413004815.
Full text國立臺灣科技大學
化學工程系
96
The objective of this work is to measure the liquid-liquid equilibrium (LLE) data of specific ternary systems for process design purposes. The LLE data of seven ternary systems, including water + methanol + methyl oleate, water + methanol + methyl linoleate, glycerol + methanol + methyl oleate, glycerol + methanol + methyl linoleate, nonane + benzene + sulfolane, nonane + toluene + sulfolane and nonane + m-xylene + sulfolane were measured at temperatures ranging from 298.15 K to 318.15 K. In general, two-phase region became smaller as increase of temperature, but this effect is not significant.The NRTL model and the UNIQUAC model were used to correlate the phase equilibrium data. The UNIQUAC model was found to be better than the NRTL model. This study also used various vesions of the UNIFAC model to predict the LLE properties. Good predictions were obtained for nonane+(benzene or toluene or m-xylene)+sulfolane systems. Unfortanately, the results for other systems are unsatisfactory.
Strachoňová, Jana. "Vliv požití ethanolu na tvorbu ethylesterů mastných kyselin pro účely průkaznosti zbytkového alkoholu v krvi." Master's thesis, 2009. http://www.nusl.cz/ntk/nusl-285477.
Full textTucci, Sara [Verfasser]. "Wax ester fermentation and fatty acid biosynthesis in the facultatively anaerobic flagellate Euglena gracilis / vorgelegt von Sara Tucci." 2008. http://d-nb.info/992456231/34.
Full textRahimi, Yasmeen. "The role of pyruvate dehydrogenase kinase in glucose and ketone body metabolism." Thesis, 2014. http://hdl.handle.net/1805/3798.
Full textThe expression of pyruvate dehydrogenase kinase (PDK) 2 and 4 are increased in the fasted state to inactivate the pyruvate dehydrogenase complex (PDC) by phosphorylation to conserve substrates for glucose production. To assess the importance of PDK2 and PDK4 in regulation of the PDC to maintain glucose homeostasis, PDK2 knockout (KO), PDK4 KO, and PDK2/PDK4 double knockout (DKO) mice were generated. PDK2 deficiency caused higher PDC activity and lower blood glucose levels in the fed state while PDK4 deficiency caused similar effects in the fasting state. DKO intensified these effects in both states. PDK2 deficiency had no effect on glucose tolerance, PDK4 deficiency produced a modest effect, but DKO caused a marked improvement, lowered insulin levels, and increased insulin sensitivity. However, the DKO mice were more sensitive than wild-type mice to long term fasting, succumbing to hypoglycemia, ketoacidosis, and hypothermia. Stable isotope flux analysis indicated that hypoglycemia was due to a reduced rate of gluconeogenesis. We hypothesized that hyperglycemia would be prevented in DKO mice fed a high saturated fat diet for 30 weeks. As expected, DKO mice fed a high fat diet had improved glucose tolerance, decreased adiposity, and were euglycemic due to reduction in the rate of gluconeogenesis. Like chow fed DKO mice, high fat fed DKO mice were unusually sensitive to fasting because of ketoacidosis and hypothermia. PDK deficiency resulted in greater PDC activity which limited the availability of pyruvate for oxaloacetate synthesis. Low oxaloacetate resulted in overproduction of ketone bodies by the liver and inhibition of ketone body and fatty acid oxidation by peripheral tissues, culminating in ketoacidosis and hypothermia. Furthermore, when fed a ketogenic diet consisting of low carbohydrate and high fat, DKO mice also exhibited hypothermia, ketoacidosis, and hypoglycemia. The findings establish that PDK2 is more important in the fed state, PDK4 is more important in the fasted state, survival during long term fasting depends upon regulation of the PDC by both PDK2 and PDK4, and that the PDKs are important for the regulation of glucose and ketone body metabolism.
Dufresne, Martin. "Nouvelles stratégies analytiques favorisant l’augmentation de la spécificité et de la sensibilité en imagerie MS." Thèse, 2016. http://hdl.handle.net/1866/18432.
Full textMass spectrometry (MS) is an analytical technique that measures the mass-to-charge ratio of ions. This technique is widely used in analytical chemistry to solve the molecular composition of complex homogenized samples. The use of homogenized samples means that all the information with respect to the initial distribution of analytes is lost. Imaging mass spectrometry (IMS) is an MS technique which is able to provide the spatial localization of a given analyte on a surface, such as thin tissue sections from various animal sources. One of the greatest advantages of IMS is its complementarity with histopathology which normally reveals the general structure of thin tissue sections as well as the localization of certain biomolecules such as proteins or of any molecules capable of specific interactions with an antibody. On the other hand, IMS is capable of imaging a wide variety of biomolecules ranging from small metabolites to the high molecular weight proteins and polymers. Among these, lipids are of particular interest for their key involvements in many biological processes. Their interest is even greater when considering that lipid imaging by classical histology is unable to differentiate between all lipid species. IMS of lipids is typically performed using matrix assisted laser desorption/ionization (MALDI). MALDI IMS can differentiate various classes of lipids and their localization within a thin tissue section by taking advantage of the specific affinity that different classes of lipids have for different matrices. The matrix deposition process, along with the choice of solvents, are key parameters that need to be considered in MALDI IMS. While MALDI offers great coverage of the phospholipidome, it fails miserably for neutral lipid analysis. Indeed, cholesterol and triacylglycerols (TAGs) are two classes of neutral lipids with very important vi biological roles which are extremely difficult to image by MALDI. We have developed three new strategies that enables the detection of neutral lipids, some of which are expressed in low abundance such as gangliosides, directly from thin tissue section using either MALDI or laser desorption/ionization (LDI). Cholesterol is a precursor of many key biomolecules such as vitamins and hormones. It’s also a major component of the cellular membrane. MALDI IMS allows in some cases imaging of the dehydrated form of cholesterol. Unfortunately, detecting cholesterol as such makes it impossible to distinguish some of its metabolites which ionize in a similar fashion and dissociate to produce the same ions. To address this issue, we have developed a new sample preparation method involving the deposition of a nanometer scale silver layer (16±2 nm) over a thin tissue section. This enables the detection by LDI MS of intact cholesterol and some fatty acid species as silver adducts with up to 5 µm in spatial resolution. Beyond cholesterol and fatty acids, TAGs is another class of highly abundant neutral lipids still poorly detected by MALDI IMS. As TAGs are the main molecules involved in energy storage of cells, they have been implicated in many metabolic diseases such as non- alcoholic fatty liver disease, atherosclerosis and even Alzheimer’s disease. The reason why TAGs are poorly detected by MALDI comes from two key factors. First, TAGs are unstable in acidic environments, typical of MALDI matrices. Second, competition effects for the ionizing proton provided by the MALDI matrix prevent TAGs from easily ionizing through this main ionization process. To overcome these limitations, we have developed a new two-step sample preparation method for TAG LDI IMS. We initially deposited a solution of carbonate buffer (pH 10.3, 85 mM) and sodium acetate (250 mM) on the tissue section to increase the amount vii of available sodium for enhanced TAG ionization. The second step consisted of sputtering a nanometer scale UV absorbing gold layer (28±3 nm) that allows for the detection of TAGs by LDI IMS with spatial resolution as low as 10 µm. When TAGs are present in low amounts in the tissue section, this method also enables the detection of cholesterol esters. Hunter’s disease is a genetic disease characterized by the abnormal accumulation of glucoaminoglycans (GAGs) and the secondary accumulation of gangliosides due to the lack of iduronate-2-sulfatase (IdS) enzyme which controls their degradation. The accumulation of both GAGs and gangliosides form deposits which induces various functional issues to different organs as well as neurologic disorders. To minimize these effects, an enzyme replacement therapy has been developed. Unfortunately, it shows efficacy in all organs except the brain due to the inability of the recombinant enzyme to cross the blood-brain barrier. To further our knowledge of the progression of the disease, using a mouse model of Hunter’s disease we have developed a MALDI based method to specifically image gangliosides in brain deposits with a spatial resolution of 5 µm. This method also permits subsequent ganglioside staining by immunohistochemtry of the tissue section. With this method, we have identified four types of ganglioside which are specific to the Hunter’s disease pathology. We were also able to detect two types of deposits, one which is enriched in short chain gangliosides and the other in long chain gangliosides.