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Enzymes and genes involved in biosynthesis of plant lipid polyestersMolina, Maria Isabel. January 2008 (has links)
Thesis (Ph.D.)--Michigan State University. Dept. of Plant Biology, 2008. / Title from PDF t.p. (viewed on July 16, 2009) Includes bibliographical references (p. 273-293). Also issued in print.
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Extraction of Atropine and Scopolamine from Datura ferox and Datura stramonium.L and sample clean-up using molecularly imprinted polymersNobaza, Kwindla Handy 16 September 2014 (has links)
M.Sc. (Chemistry) / The extraction of the atropine and scopolamine alkaloids from both Datura ferox and Datura stramonium was carried out in this study to investigate potential of these plants as a source of these alkaloids. Tropane alkaloids such as atropine occur naturally in many members of several plant families, especially the Solanaceae, Erythroxylaceae, Proteaceae and Convolvulaceae families. Hyoscyamine or its racemic mixture atropine is used as an antidote to organophosphate insecticides, or as a nerve agent to dilate the pupil for retina examinations. Scopolamine or hyoscine is used to treat motion sickness, among other uses. Tropane alkaloids are often difficult to synthesise, and their extraction from commercial sources is therefore of some commercial interest. A systematic study was carried by comparing different extraction methods for the efficiencies of tropane alkaloid (TA) extraction at ambient pressure. The two plants selected are already widely spread as weeds in many regions in South Africa and are therefore well adapted to the local conditions. Among the extraction methods, TA’s were extracted in their acidic form using dilute aqueous acids with 5% sulfuric acid giving the highest yield of both atropine and scopolamine. Alternatively, the TA’s were extracted in their basic form from the plant material using basified organic solvents. The overall yields obtained were not significantly different from those obtained by using dilute aqueous acids, with D. ferox giving approximately 0.24 % and 0.0028 % scopolamine and atropine, respectively. D. stramonium on the other hand gave approximately 0.037 % and 0.002% atropine and scopolamine, respectively. Different plant parts were also tested in order to determine if there was an advantage in extracting the tropane alkaloids at a particular time in the growth, but concluded that the best option was to extract the seeds for various reasons such as the presence of relatively less chlorophyll...
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Novel Biobased Resins using Sucrose Esters of Plant OilsPan, Xiao January 2011 (has links)
Interest in using renewable raw materials to prepare biobased monomers, polymers, and materials is rapidly increasing. The goal of the research described is to develop branched polyesters of plant oil fatty acids, using different core pol yo ls (i.e. sucrose, dipentaerythritol, and tripentaerythritol) and plant oils (i.e. linseed, safflower, and soybean), into curing systems that have potential uses in applications such as coatings, composites, and adhesives. This study is mainly focused on the use of sucrose as the core
polyol in the soyate resins. Sucrose esters and their derivatives have a compact structure, high density, and high functionality-double bonds, epoxides, or hydroxyls. When considering the use of sucrose
ester compounds to form cross linked materials, the rigid core of sucrose can potentially impart hardness to the thermoset, and the high functionality can lead to rapid gelation and high cross link density. Thus, these novel biobased resins using sucrose esters of plant oils have the potential to be a significant advance in biobased resin technology, as well as to be competitive with the conventional petroleum-based resins.
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High resolution nuclear magnetic resonance investigations of polymethylenic plant biopolymers structural determinations and post-depositional ammonia nitrogen incorporation /Turner, Jeffrey W., January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 157-170).
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