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Purification and biological activity of oregonin, a novel bioactive diarylheptanoid found in the leaves and bark of Alnus rubra (red alder)Lea, Carmen 27 August 2020 (has links)
Red alder (Alnus rubra) is the most commercially important hardwood tree species in the Pacific Northwest and has a long history of traditional medicinal use as a source of fungicide and insecticide. Chemical analysis has shown that the diarylheptanoid oregonin ((5S)-1,7-bis(3,4-dihydroxyphenyl)-5-(β-D-xylopyranosyloxy)-heptan-3-one) is the dominant phytochemical contributing to medicinal activity. It was recently discovered that high oregonin concentration in alder leaves is associated with enhanced resistance to western tent caterpillar (Malacosoma californicum), a leaf eating lepidopteran herbivore; however, oregonin has never been directly tested on insects, or red alder-associated fungal species. In this thesis, a novel purification method was developed for the preparative extraction of oregonin from red alder leaf and bark material to directly test its biological activity. A battery of insect feeding and toxicity bioassays were carried out with several tree-defoliating caterpillars, and fungal inhibition was tested against a range of plant-associated fungal species, including several alder-associated species. This research represents the first evaluation of oregonin biological activity on insects, plant-associated fungi of the phyla Basidiomycota, and fungal-like pathogens of the phyla Oomycota. Oregonin exhibited promising insect feeding deterrent activity against generalist lepidopteran pests, including cabbage loopers (Trichoplusia ni), white-marked tussock moths (Orgyia leucostigma), and fall webworm (Hyphantria cunea) at similar concentrations shown to reduce western tent caterpillar herbivory in alder leaf bioassays. The results suggest that oregonin concentration has potential for selection as a breeding trait in managed populations of red alder to improve host resistance to leaf-eating pests. / Graduate / 2021-08-10
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Development of a method for the screening of sports doping compounds using multidimensional liquid chromatography and time of flight mass spectrometryWalsh, Robert James 24 July 2018 (has links)
Athletes have often resorted to a variety of methods to gain an edge in sporting competitions. One such method is through doping, the use of compounds or methods to produce a theoretically enhancing biological effect. In order to combat doping, many governing sports bodies have prohibited specific compounds or methods and installed programs to test for these compounds in athletes. However, due to the large number of banned substances and the varying chemistries of those compounds, it can be challenging and time consuming to determine the presence of those compounds in an athlete’s sample. Therefore, there is a necessity to develop a quick and sensitive method that can precisely and accurately screen for banned substances.
This research was an attempt to develop such a method. This was accomplished using multidimensional liquid chromatography with time of flight mass spectrometry. While none of the methods tested here were useful for screening all 79 compounds tested in a single injection, a multi-method approach was evaluated in lieu of a multi-residues single method process The analytical run time was less than 10 minutes for each method. Further studies were performed to determine the limit of detection, linearity, lifetime, robustness and the optimal solid phase extraction method.
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A Semiquantitative Analysis of PCB and P,P-DDE Residues in Stranded Marine Mammals Using High Performance Liquid ChromatographyHayteas, David Lawrence 01 January 1996 (has links)
Organochlorines are ubiquitous pollutants of the marine environment. These lipid-soluble and highly persistent compounds are found in detectable amounts in almost all marine organisms, and accumulate in the lipid tissues of marine animals. This bioaccumulation leads to biomagnification of these contaminants in higher trophic levels. Near the top of many marine food chains are found the marine mammals, in whose blubber high levels of organochlorine residues have been measured. The most commonly occurring of these pollutants in these animals are the polychlorinated biphenyls (PCB's) and p,p-DDE, a metabolite of the insecticide DDT. These substances have been shown to cause disruptions in the endocrine, immune, and reproductive systems, and are passed from mother to offspring through the placenta and by lactation. Presence and levels of residues of these compounds are, therefore, monitored in marine mammals to provide an indication of the health of a given population and the environment in which they live. Such monitoring is generally done with the use of gas chromatography (GC). High performance liquid chromatography (HPLC) is little used due to the poor ultraviolet (UV) absorbance properties of many of the organochlorines. PCB's and p,p-DDE do absorb UV well enough at concentrations usually encountered in marine mammals to permit the use of HPLC for detection and semiquantification of these substances. A method was developed for the screening of blubber of marine mammals for total PCB's and p,p-DDE using HPLC. The method was applied to the detection and approximation of levels of these two organochlorines in marine mammals from the east and west coasts of the United States. Geographical differences in levels of the two pollutants were found, indicating differences in primary feeding ranges. Evidence of placental transfer of these two organochlorines was also found. Especially high residue levels were found in the blubber of stranded killer whales, indicating that acquisition of high pollutant burdens is still a problem in these top predators. It was concluded that HPLC can be used to screen marine mammals for PCB's and p,p-DDE, and that residue levels determined can be useful in investigating species range, pollutant burdens, and health of populations.
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Automated derivatization and identification of controlled substances via total vaporization solid phase microextraction (Tv-Spme) and gas chromatography-mass spectrometry (Gc-Ms)Hickey, Logan D. January 2018 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Gas chromatography-mass spectrometry (GC-MS) is one of the most widely used instrumental techniques for chemical analyses in forensic science laboratories around the world due to its versatility and robustness. The most common type of chemical evidence submitted to forensic science laboratories is seized drug evidence, the analysis of which is largely dominated by GC-MS. Despite this, some drugs are difficult or impossible to analyze by GC-MS under normal circumstances. For these drugs, derivatization can be employed to make them more suitable for GC-MS.
In Chapter 1, the derivatization of primary amino and zwitterionic drugs with three different derivatization agents, trifluoroacetic anhydride (TFAA); N,O-bis(trimethylsilyl)trifluoroacetamide + 1% trimethylchlorosilane (BSTFA + 1% TMCS); and dimethylformamide dimethylacetal (DMF-DMA), is discussed. The chromatographic performance was quantified for comparison between the derivatives and their parent drugs. Peak symmetry was compared using the asymmetry factor (As), separation efficiency was measured by the number of theoretical plates (N), and sensitivity was compared by measuring the peak areas.
In Chapter 2, derivatization techniques were adapted for an automated on-fiber derivatization procedure using a technique called total vaporization solid phase microextraction (TV-SPME). TV-SPME is a variation of SPME in which a small volume of sample solution is used which can be totally vaporized, removing the need to consider the equilibrium between analytes in the solution and analytes in the headspace. By allowing derivatization agent to adsorb to the SPME fiber prior to introduction to the sample vial, the entire derivatization process can take place on the fiber or in the headspace surrounding it. The use of a robotic sampler made the derivatization procedure completely automated.
In Chapter 3, this on-fiber derivatization technique was tested on standards of 14 controlled substances as well as on realistic samples including simulated “street meth”, gamma-hydroxybutyric acid (GHB) in mixed drinks, and hallucinogenic mushrooms, and was also tested on several controlled substances as solid powders.
Future work in this area is discussed in Chapter 4, including adapting the method to toxicological analyses both in biological fluids and in hair. Some of the expected difficulties in doing so are discussed, including the endogenous nature of GHB in the human body. The presence of natural GHB in beverages is also discussed, which highlights the need for a quantitative addition to the method. Additional method improvements are also discussed, including proposed solutions for complete derivatization of more of the analytes, and for decreasing analysis time.
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Urinary Volatile Organic Compounds for Detection of Breast Cancer and Monitoring Chemical and Mechanical Cancer Treatments in MiceTeli, Meghana 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The aim of this study is to identify metabolic transformations in breast cancer through urinary volatile organic compounds in mammary pad or bone tumor mice models. Subsequently, it focuses on investigating the efficacy of therapeutic intervention through identified potential biomarkers. Methods for monitoring tumor development and treatment responses have technologically advanced over the years leading to significant increase in percent survival rates. Although these modalities are reliable, it would be beneficial to observe disease progression from a new perspective to gain greater understanding of cancer pathogenesis. Analysis of cellular energetics affected by cancer using bio-fluids can non-invasively help in prognosis and selection of treatment regimens. The hypothesis is altered profiles of urinary volatile metabolites is directly related to disrupted metabolic pathways. Additionally, effectiveness of treatments can be indicated through changes in concentration of metabolites. In this ancillary experiment, mouse urine specimens were analyzed using gas chromatography-mass spectrometry, an analytical chemistry tool in identifying volatile organic compounds. Female BALB/c mice were injected with 4T1.2 murine breast tumor cells in the mammary fat pad. Consecutively, 4T1.2 cells were injected in the right iliac artery of BALB/c mice and E0771 tumor cells injected in the tibia of C57BL/6 mice to model bone tumor. The effect of two different modes of treatment: chemical drug and mechanical stimulation was investigated through changes in compound profiles. Chemical drug therapy was conducted with dopamine agents, Triuoperazine, Fluphenazine and a statin, Pitavastatin. Mechanical stimulation included tibia and knee loading at the site of tumor cell injection were given to mice. A biological treatment mode included administration of A5 osteocyte cell line. A set of potential volatile organic compounds biomarkers differentiating mammary pad or bone confined tumors from healthy controls was identified using forward feature selection. Effect of treatments was demonstrated through hierarchical heat maps and multivariate data analysis. Compounds identified in series of experiments belonged to the class of terpenoids, precursors of cholesterol molecules. Terpene synthesis is a descending step of mevalonate pathway suggesting its potential role in cancer pathogenesis. This thesis demonstrates the ability of urine volatilomics to indicate signaling pathways inflicted in tumors. It proposes a concept of using urine to detect tumor developments at two distinct locations as well as to monitor treatment efficacy.
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Detection of Illicit Drugs in Various Matrices Via Total Vaporization Solid-Phase MicroextractionDavis, Kymeri Elizabeth 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In Headspace Solid-Phase Microextraction (Headspace SPME), a sample is heated to encourage a portion of the analyte into the headspace of a vial. A coated fiber is introduced into the sample headspace and the analyte is adsorbed onto the fiber coating. Total Vaporization Solid-Phase Microextraction (TV-SPME) is a technique that is derived from this technique. In TV-SPME, liquid samples are completely vaporized allowing for better adsorption and fewer matrix effects. This method does not require any sample preparation, utilizes minimal supplies and can be automated, making it both an efficient and cost-effective method. Chapter 1 will discuss the theory of SPME and TV-SPME.
In Chapter 2, the detection of ɣ-hydroxybutyric acid (GHB) and ɣ-butyrolactone (GBL) in beverages is discussed. The detection of these compounds in beverages is of importance because these drugs may be used to facilitate sexual assault. This crime utilizes substances that cause sedation and memory loss. The derivatization of GHB as well as the properties that make GHB difficult to detect will be discussed.
Chapter 3 will discuss the detection of methamphetamine and amphetamine (as their trifluoroacetyl derivatives), GBL, and the trimethylsilyl derivative of GHB in human urine. Amphetamine is a metabolite of methamphetamine, therefore, both drugs should be identified within biological samples. GHB and GBL are metabolites of one another and interconvert when in aqueous solution. This interconversion will be discussed.
Chapter 4 will cover method optimization of the Total Vaporization Solid-Phase Microextraction method. Analytes of interest for these analyses were methamphetamine, amphetamine, GHB, and GBL. The optimal extraction temperature ranging from 60-160°C of each drug will be discussed as well as why higher temperatures may not be suitable for this method. A limit of detection study for methamphetamine and amphetamine will also be covered.
Chapter 5, the future work chapter, will discuss future analyses using the Total Vaporization Solid-Phase Microextraction method including the analysis of powder materials, plant material, and toxicological samples. Powder material will include the analysis of individual powdered drugs as well as realistic drug mixtures. Some analyses on individual powder samples has already been completed and will be shown. Plant material will include the analysis of naturally occurring compounds found in marijuana plants as well as synthetic cannabinoids. Toxicological samples will expand on previously mentioned urine samples to include drugs such as benzoylecgonine and THC-COOH.
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Thin layer chromatography of platinum and palladium-ammine complexesMontezuma, Edgar Roberto 01 January 1968 (has links)
Recent work in this laboratory has centered around Platinum metals and their coordination compounds. Specifically, Thin-Layer Chromatography of Platinum metal ions has been reported in one of the recent dissertations (1). The purpose of the present work was to carry out a systematic study of Thin-Layer Chromatography on the following complexes: Tetrammine Platinum (II) Chloride [Pt (NH3)4]Cl2 Tetraammine Palladium (II) Chloride. [Pd (NH3)4]Cl2 Hexammine Platinum (IV) Chloride. [Pt (NH3)6]Cl4 Hexammine Palladium (IV) Chloride [Pd (NH3)6]Cl4
After the complexes had been synthesized, the main problem lay in finding a suitable adsorbent and solvent system for separating a mixture of all four complexes as well as an appropriate locating reagent, so that once the separation had been accomplished, complexes could be identified.
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Studies on Quality Evaluation of Biopharmaceuticals by Chromatographic and Electrophoretic Techniques / クロマトグラフィー及び電気泳動技術によるバイオ医薬品の品質評価に関する研究Kubota, Kei 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21072号 / 工博第4436号 / 新制||工||1689(附属図書館) / 京都大学大学院工学研究科材料化学専攻 / (主査)教授 大塚 浩二, 教授 松原 誠二郎, 教授 秋吉 一成 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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Post-transcriptional Modification Characterizing and Mapping of Archaea tRNAs Using Liquid Chromatography with Tandem Mass SpectrometryYu, Ningxi 18 June 2019 (has links)
No description available.
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Application of Non-Targeted Volatile Metabolomics in Plant PathologyShe, Jinyan 08 December 2017 (has links)
Our study focuses on the application of volatile metabolomics and chemometrics in plant pathology. Specifically, volatile metabolites or volatile organic compounds (VOCs) from the American chestnut tree (Castanea dentata) and its pathogenic fungus Cryphonectria parasitica have been investigated. The American chestnut was once a dominant tree species in the eastern forests of the United States. However, it was nearly devastated by the fungal pathogen C. parasitica. The loss of this tree species has significantly impacted the ecosystem. Therefore, preservation and restoration of American chestnut are crucial. Chapter one provides an overview of mass spectrometry based volatile metabolomics and their implementation in the investigation of plant pathology. The study of volatile metabolites profiles from virulent and hypovirulent strains of C. parasitica are presented in chapter two. The microbial volatile organic compounds (MVOCs) profiles were analyzed via nondestructive sampling method, headspace solid phase microextraction (HS-SPME), combined with gas chromatography (GC)-mass spectrometry (MS). The results indicate that the MVOCs profiles emitted from these two strains are significantly different. In general, compared with its hypovirulent strains, high emissions of sesquiterpenes were observed in the virulent strains. Furthermore, the study explored MVOCs differences associated with hypovirulence processes. The study found that both hypovirulence and aging can alter the virulent strains' MVOCs, and the process can be observed via their volatile metabolites. Chapter three describes the effects of aging, cultivation medium, and pH on fungal volatile metabolite profiles, all of which can change the strength of MVOCs emission and their composition. An acidic environment favors fungal bioactivity and therefore enhanced MVOCs emission. However, due to the inherently low MVOCs production from hypovirulent strains, the pH effect was less apparent in the hypovirulent isolates. The strength of MVOCs emission was highly correlated to the fungal expansion in virulent strains for the first 14 days. The overall emission from hypovirulent strains was relatively steady during the 28-day observation. Finally, the cultivation media are critical to the fungal MVOCs production. Among the tested media, cornmeal was least favorable for MVOCs production for both strains. Finally, Chapter Four presents a study of the total constitutive phenolic content estimation and volatile organic compounds identification from four species of chestnut tree leaf tissues. Folin Ciocalteu reagent assay with UV/Vis spectrophotometry was applied to estimate the total phenolic content in leaf tissues of American chestnut (Castanea dentata), Chinese chestnut (Castanea mollissima), and their backcross breeding generations (B3F2 and B3F3). The results from leaf tissue extraction in methanol/water (95:5 v/v), pH 2, and analyzed under the UV/Vis at 765 nm show that the variations among these tree species are significant (ANOVA, p < 0.05). The kinetics of phenolic compound solid-liquid extraction was elaborated using Peleg, second order, and power law models. Moreover, the analysis of VOCs collected from these species indicated that the distinction of American and Chinese chestnut could be archived via their VOCs, while the hybrids’ leaf VOCs are different from their parents’.
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