Evidence indicates seed oil melting point is likely an adaptive quantitative trait in many flowering plant species. An adaptive hypothesis suggests selection has changed the melting point of seed oils to covary with germination temperatures because of a trade-off between total energy stores and the rate of energy acquisition during germination under competition. The predicted differences in relative fitness under different temperatures have not yet been tested and little is known about the genetic basis of differences in oil composition. I used Arabidopsis thaliana to: (1) assess the fitness consequences of high and low melting point seeds germinating at different temperatures, (2) assess what genes underlie natural variation in seed oil composition, and (3) consider how these genes may be used to create oils with particular characteristics. To assess the effects of seed oil melting point on timing of seedling emergence and fitness, I competed high and low melting point lines of A. thaliana under cold and warm temperatures. Emergence timing between these lines was not significantly different at either temperature, which comported with warm temperature predictions but not cold temperature predictions. Under all conditions, plants competing against high melting point lines had lower fitness relative to those against low melting point lines, which matched expectations for undifferentiated emergence times. To assess the genetic basis of naturally occurring variation in seed oil melting point, the seed oil compositions of 391 accessions of A. thaliana were used in a genome-wide association study. Twelve genes were tightly linked with SNPs significantly associated with seed oil melting point variation. Seven encoded lipid synthesis enzymes or regulatory products. The remaining 5 encoded products with no clear relation to seed oil melting point. Results suggest selection can alter quantitative trait variation in response to local conditions through a small set of genes. 268 seed-expressed, candidate genes were linked to 103 SNPs associated with A. thaliana seed oil fatty acids. Eight genes were involved in lipid metabolism, and thirty-four encoded regulatory products. I discuss how knowledge of these genes can be used to breed and engineer desirable oil compositions for industry and nutrition. / text

Natural variation in the relative proportions of saturated and unsaturated fatty acids in seed oils of plants is enormous when considered across a broad taxonomic range of oil seeds. It has been shown that this variation follows a latitudinal cline where the proportions of unsaturated fatty acids increases with increasing latitude as the unsaturated fatty acids in seeds provide energy at a faster rate to germinating seeds at higher latitudes. This variation which follows a latitudinal cline suggests that there may be an adaptive role for this variation. We tested this hypothesis in Arabidopsis thaliana which followed the same trend seen in Helianthus and other angiosperms. In order to understand the underlying genetics of the regulation of the relative proportions of fatty acids and their role in plant evolution, we mapped quantitative trait loci (QTLs) and candidate genes. Here we identified 67 major QTLs responsible for fatty acid synthesis in A. thaliana in Ler-0 x Sha, Ler-0 x Col-4, Ler-2 x Cvi and Ler-0 x No-0 RIL populations. Eight candidate genes were identified based on what is known about seed oil biosynthesis in A. thaliana. Six of the candidate genes collocated to most of the major QTLs. In order to demonstrate that a particular allelic variant is indeed causally related to the phenotype, we investigated DNA polymorphisms in the parental and the RIL line alleles of the collocating candidate genes. Single nucleotide polymorphisms (SNPs) were identified in the collocating candidate genes to study the correlation between the sequence variants and the particular phenotype. We identified 232 SNPs with 77 in the putative regulatory regions upstream of the 5’UTR, 61 in the introns, 18 in the 5’UTR regions, 2 in the 3’UTR regions, and 45 occurring in the exons with 10 non-synonymous substitutions affecting the amino acid residues. We also detected 44 insertions/deletions in the coding, non-coding, 5’UTR, 3’UTR and the regulatory regions. Sequence variation in the fatty acid genes due to SNPs and insertions/deletions should be valuable in tests of association to investigate how the relative proportions of saturated and unsaturated fatty acids are regulated in wild plants and what role they have played in plant evolution and also in breeding oil seed crops that are healthier or have two types of fatty acids in proportions appropriate for different uses. / text

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Orientador: Maria Isabel Felisberti / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-18T09:32:15Z (GMT). No. of bitstreams: 1 Robles_SebastianGomez_M.pdf: 2542883 bytes, checksum: 41418f1c146d0909e848014acbd2b608 (MD5) Previous issue date: 2011 / Resumo: A procura de novos materiais poliméricos oriundos de matérias primas renováveis é de grande importância científica, tecnológica e ambiental, dado que elas podem substituir as de origem na cadeia do petróleo, além de contribuir para a diminuição de gases de efeito estufa e o acúmulo de lixo plástico. Os óleos vegetais são matérias primas renováveis constituídas principalmente de triglicerídeos, cujas características estruturais fornecem uma ampla gama de possibilidades sintéticas para a obtenção de diversos materiais poliméricos, os quais têm apresentado propriedades semelhantes àqueles polímeros convencionais oriundos do petróleo, assim como outras propriedades interessantes como amortecimento mecânico e memória de forma. O grande potencial brasileiro para a produção de óleo de semente de seringueira (OSS), aliado ao fato de que ele não compete com a indústria alimentar, faz deste óleo uma alternativa importante para a obtenção de novos polímeros com benefícios econômicos e ambientais significativos. Neste trabalho foi sintetizada uma série de copolímeros vinílicos de estireno e macrômeros de OSS. Estes macrômeros foram obtidos pela rota sintética constituída de duas etapas: glicerólise do óleo seguida de maleinização para obtenção de monômeros de elevada massa molar e funcionalidade variando entre 2 e 4. Os produtos intermediários desde o OSS até os macrômeros foram caracterizados por CCD, FT-IR, espalhamento Raman e RMN de H e C. Foram obtidos copolímeros de OSS-estireno variando as condições de síntese (temperatura, tempo e composição) visando o estudo do efeito destas variáveis na estrutura e propriedades dos materiais. Os copolímeros sintetizados foram caracterizados por ensaios de intumescimento e extração de solúveis, DMA, TG/DTG, ensaios de degradação hidrolítica e RMN de H e GPC da fração solúvel. Encontrou-se que os copolímeros sintetizados possuem uma estrutura complexa dependente da composição, tempo e temperatura de reação, sendo caracterizada principalmente por uma rede tridimensional com oligômeros e/ou polímeros inseridos nela. Alguns dos polímeros obtidos apresentaram propriedades interessantes para serem aplicados como isolantes acústicos / Abstract: The search for new polymeric materials from renewable raw materials is of great scientific, technological and environmental importance, since they can replace those made from petroleum, and contribute to reducing greenhouse gases and the accumulation of plastic waste. Vegetable oils are renewable resources consisting mainly of triglycerides, whose structural features provide a wide range of synthetic possibilities to obtain various polymeric materials, which have shown similar properties to those of conventional polymers from petroleum, as well as other interesting properties such as damping and shape memory. The great potential of Brazil for the production of rubber seed oil (RSO), coupled with the fact that it does not compete with the food industry, makes this oil an important alternative to obtain new polymers with significant economic and environmental benefits. In this work we synthesized a series of copolymers of styrene and vinyl macromers of RSO. These macromers were obtained by synthetic route consists of two steps: glycerolysis oil followed by maleinization to obtain monomers with high molecular weight and functionality ranging from 2 to 4. Intermediate products from the RSO to the macromers were characterized by TLC, FT-IR, Raman, H NMR and C NMR. Copolymers of RSO and styrene were obtained by varying the synthesis conditions (temperature, time and composition) in order to study the effect of these variables on the structure and properties of the materials. The copolymers were characterized by swelling and extraction of soluble fraction, DMA, TG/DTG, hydrolytic degradation and H NMR and GPC of the soluble fraction. It was found that the copolymers possess a complex structure dependent on the composition, temperature and reaction time and characterized by a three-dimensional network with oligomers and/or polymers inside it. Some of the resulting polymers showed interesting properties to be used as soundproofing / Mestrado / Quimica Organica / Mestre em Química

Submitted by Biblioteca da Faculdade de Farmácia (bff@ndc.uff.br) on 2017-04-10T17:15:47Z No. of bitstreams: 1 Cordeiro, Lara Bissonho de Almeida [Dissertação, 2012].pdf: 7477331 bytes, checksum: 808ccdd7f27f43a63cb9c2f3cf8f6704 (MD5) / Made available in DSpace on 2017-04-10T17:15:47Z (GMT). No. of bitstreams: 1 Cordeiro, Lara Bissonho de Almeida [Dissertação, 2012].pdf: 7477331 bytes, checksum: 808ccdd7f27f43a63cb9c2f3cf8f6704 (MD5) / Óleos vegetais são ricos em ácidos graxos essenciais, sendo estes ácidos necessários para manter a integridade da pele e a barreira de água, prevenindo assim a formação de feridas. Ferida pode ser definida como toda alteração da integridade anatômica da pele, resultante de qualquer tipo de trauma. O tratamento de feridas envolve aspectos sistêmicos e locais. O ácido oléico é o ácido graxo mais freqüentemente encontrado na composição dos óleos fixos, sendo acompanhado pelos ácidos linoléico e linolênico. Os objetivos deste trabalho foram desenvolver e avaliar a estabilidade física de emulsões O/A contendo óleo de semente de maracujá. Emulsões O/A contendo 10,0% (p/p) de óleo de semente de maracujá foram preparadas utilizando as ceras Lanette®, Polawax®, e monoestearato de glicerila e o emulsionante polimérico Pemulen® como base das formulações, variando-se as concentrações dos adjuvantes farmacotécnicos: miristato de isopropila, propilenoglicol e glicerina. O tipo de emulsão foi verificado pelo método das medidas de condutividade elétrica e o aspecto, homogeneidade e características organolépticas avaliadas através de análises macroscópicas. Para avaliar a estabilidade acelerada, as amostras foram submetidas a diferentes condições de estresse e analisadas a partir do valor de pH, análises macroscópicas, centrifugação, espalhabilidade, viscosidade aparente e comportamento reológico. As mulsões preparadas com óleo de maracujá, 0,3% (p/p) Pemulen®, apresentaram-se estáveis com propriedades pseudoplásticas e tixotrópicas. As características macroscópicas e valores obtidos de pH, viscosidade aparente e espalhabilidade durante a estocagem indicaram estabilidade da formulação / Vegetable oils are rich in essential fatty acids, these acids being necessary to maintain the integrity of the skin barrier and the water, thus preventing the formation of wounds. Wound can be defined as any change in the anatomical integrity of the skin, resulting from any kind of trauma. Treatment of wounds involves local and systemic aspects. Oleic acid is the fatty acid most frequently found in the composition of fixed oils, accompanied by linoleic and linolenic acids. Our objectives were to develop and evaluate the physical stability of O/W emulsions containing passion fruit seed oil. Emulsions containing 10.0% (w / w) of passion fruit seed oil were prepared using waxes Lanette ®, Polawax ®, glyceryl monostearate and the polymeric emulsifier Pemulen ® based formulations, varying concentrations of pharmaceutical adjuvants: isopropyl myristate, propylene glycol and glycerin. The emulsion type was verified by the method of the electrical conductivity measurements and the appearance, consistency and organoleptic properties were evaluated by macroscopic analysis. To evaluate the accelerated stability, samples were subjected to different stress conditions and the pH value, macroscopic analysis, centrifugation, viscosity, spreadability and rheological behavior were evaluated. The emulsions prepared with passionflower oil, 0.3% (w/w) Pemulen® were stable and presented thixotropic and pseudoplastic properties. The macroscopic characteristics and values of pH, viscosity and spreadability during storage showed stability of the formulation

Whole grain and bran samples of two Malawian sorghums, Phatafuli, (a brown-coloured condensed tannin variety) and Shabalala, (a white-coloured condensed tannin-free variety) were analysed for their content of total phenols, condensed tannins and antioxidant activities. The effect of oxidizing conditions during extraction, and the storage stability of a freeze-dried crude phenolic extract (CPE) from the condensed tannin sorghum bran as influenced by packaging, storage temperature and length of storage, in relation to its content of total phenols, condensed tannins and antioxidant activity was also investigated. Antioxidant activity of the CPE, in comparison with tertiary butyl hydroquinone (TBHQ), was then evaluated in sunflower oil at concentrations of 1000, 1500 and 2000 ppm in the absence or presence of ferric ions at 2.2 and 4.4 ppm in the dark at 65oC.Progression of oxidation was monitored by measurement of peroxide values (PV) and anisidine values (AV) during a 14-day storage period. Phatafuli contained higher content of total phenols and antioxidant activity than Shabalala both in the whole grain and the bran, probably due to the presence of condensed tannins in Phatafuli sorghum, which were not detected in Shabalala sorghum. For both sorghum varieties, the bran contained higher levels of total phenols and antioxidant activity than the whole grain, confirming that phenolic compounds in sorghum are largely concentrated in the bran. Antioxidant activities of the sorghum varieties correlated highly with their total phenol and condensed tannin contents, suggesting that the phenolic compounds were largely responsible for the antioxidant activities of the sorghum grains. Bubbling of oxygen into the liquid crude phenolic extract did not have any significant effect on the parameters tested. Similarly, vacuum-packed samples did not differ significantly in the parameters tested from the samples that were not vacuum-packed. CPE samples stored at –20oC had significantly higher levels of total phenols, condensed tannins and antioxidant activity than those stored at 25oC during some days of storage. Storage time was however the major factor influencing the levels of total phenols, condensed tannins and antioxidant activity of the CPE from Phatafuli sorghum during storage, which suggested that CPE from condensed tannin sorghum bran might need to be used shortly after extraction to ensure optimum antioxidant activity. There was an insignificant correlation between the antioxidant activities of the CPE and their phenolic contents during storage, which could have been due to the formation of new compounds with a lower antioxidant capacity. The CPE inhibited oxidation of sunflower oil as shown by lower peroxide values and anisidine values compared to control samples. The CPE was however less effective in reducing peroxide values compared to TBHQ, but was similar to TBHQ in reducing anisidine values. In the presence of ferric ions, the CPE appeared to be less effective in reducing peroxide values compared to TBHQ, but appeared to be more effective than TBHQ in reducing anisidine values. The results showed that the tannin sorghum bran CPE appeared to act as both lipid radical scavengers and metal chelators. The CPE however imparted colour to the sunflower oil, which could limit its application as a natural antioxidant in edible oils. / Dissertation (MSc(Agric) Food Science and Technology)--University of Pretoria, 2008. / Food Science / unrestricted

Simarouba glauca, a non-edible oilseed crop native to South Florida, is gaining popularity as a feedstock for the production of biodiesel. The University of Agriculture Sciences in Bangalore, India has developed a biodiesel production model based on the principles of decentralization, small scales, and multiple fuel sources. Success of such a program depends on conversion efficiencies at multiple stages. The conversion efficiency of the field-level, decentralized production model was compared with the in-laboratory conversion efficiency benchmark. The study indicated that the field-level model conversion efficiency was less than that of the lab-scale set up. The fuel qualities and characteristics of the Simarouba glauca biodiesel were tested and found to be the standards required for fuel designation. However, this research suggests that for Simarouba glauca to be widely accepted as a biodiesel feedstock further investigation is still required.

There is limited research on High Surfactant Oil Concentrates (HSOC), so studies were conducted for their evaluation. Multiple MSO-based (HSMOC) and POC-based (HSPOC) HSOCs were tested with glyphosate plus dicamba or glyphosate plus tembotrione. The addition of HSMOCs provided greater indicator species control HSPOCs when added to either herbicide tank-mix. When multiple experimental oil to surfactant ratios were added to glyphosate plus dicamba or glyphosate plus tembotrione, there were no differences among experimental HSOC ratios when added to either tank-mix by 28 days after application. Since oil adjuvant rates can be based on either treated area or percent of spray solution, oils were added to either dicamba or tembotrione to evaluate rate methods. There were few differences in species control when oils were added to dicamba. Quinoa and amaranth control were more consistent when using the percent volume-based rates with tembotrione.