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Underexplored environments such as soil samples continue to be an untapped source of bacterial strains with great potential to produce secondary metabolites for medicinal applications. As a result, these microorganisms represent a broad and yet unknown reservoir of new strains capable of producing these novel compounds. The current research primarily seeks to perform the isolation, purification, and characterization of secondary metabolites from a soil bacterium (Janthinobacterium lividum TAJX1901). The isolated soil bacterium was successfully cultured on rich media agar plates, followed by extraction using methanol and chloroform. The purification methods utilized include flash column chromatography, preparative thin-layer chromatography, and high-performance liquid chromatography. For structural elucidation, UV-Vis analysis, infrared spectroscopy, and nuclear magnetic resonance spectroscopy were employed. The extraction resulted in a dominant violet pigment soluble in methanol. Results revealed the presence of highly conjugated, polar, and aromatic compounds (violacein or relatives of violacein) and dioctyl phthalate (a contaminant).

Graduate students in the Brigham Young University Chemistry Department are working to develop a filtering device that can be used to separate substances into their constituent parts. The device consists of a monomer and water mixture that is polymerized into a monolith inside of a capillary. The ideal monolith is completely solid with interconnected pores that are small enough to cause the constituent parts to pass through the capillary at different rates, effectively separating the substance. Although the end objective is to minimize pore sizes, it is necessary to first identify an experimental region where any combination of input variables will consistently yield homogeneous monoliths capable of flow. To accomplish this task, an experimental mixture design is used to model the relationship between the variables related to the creation of the monolith and the probability of creating an acceptable polymer. The results of the mixture design suggest that, inside of the constrained experimental region, mixtures with higher proportions of monomer and surfactant, low amounts of initiator and salt, and DEGDA as the monomer have the highest probability of producing a workable monolith. Confirmatory experiments are needed before future experimentation to minimize pore sizes is performed using the refined constrained experimental region determined by the results of this analysis.

A ervilha é um dos alimentos mais produzidos no mundo e, conseqüentemente, tem uma grande importância para a nutrição humana, sendo comercializada sob várias formas: fresca, seca, congelada e enlatada, necessitando de cozimento antes de ser consumida. Sendo assim, podem ocorrer alterações em sua composição durante esses processamentos. O presente trabalho teve como objetivos avaliar as mudanças ocorridas devido ao processamento na composição centesimal e no perfil de carotenóides em ervilhas frescas (tortas - com vagem comestível - e em grão), secas e enlatadas e relacionar esses dados com sua origem e safra. Foram analisados seis lotes de ervilhas tortas provenientes de duas regiões produtoras (cruas e cozidas por 5 minutos), três lotes de ervilhas frescas (cruas e cozidas por 7 minutos), dois lotes de ervilhas enlatadas (processadas e sua matéria-prima) e três lotes de ervilhas secas (cruas e cozidas por 35 minutos). A umidade em ervilhas tortas diferiu entre safras e regiões produtoras e em ervilhas em grão, aumentou após o cozimento em duas amostras e variou entre safras. O cozimento ocasionou perdas nos teores de Resíduo Mineral Fixo (RMF) em ervilhas em grão e secas. Em ervilhas enlatadas, o processamento causou aumento da umidade e RMF, devido à incorporação de água e sais. Os carotenóides encontrados foram a luteína, o β-caroteno e traços de violaxantina. O perfil de carotenóides em ervilhas tortas, em grão e secas não se alterou após o cozimento, já o enlatamento revelou um aumento aparente no teor de luteína em apenas um dos lotes estudados. Os teores de luteína e β-caroteno variaram entre as diferentes épocas de coleta de ervilhas tortas, em grão e secas, porém não foi observada variação entre as duas regiões produtoras de ervilhas tortas. Os teores de luteína variaram entre as matérias-primas dos diferentes fornecedores de ervilhas enlatadas. Apenas o β-caroteno possui atividade pró-vitamínica A, porém está presente em quantidade insuficiente para fazer das ervilhas fontes desse nutriente. / Pea is one of the world\'s most produced foods and therefore has great importance for human nutrition, being commercialized under different conditions: fresh, dried, frozen and canned, and further cooking is needed before being consumed. As a result, processing can cause some changes in its composition. The aim of the present work was to evaluate the changes in the centesimal composition and carotenoids profile of garden peas, snow peas, dry peas and canned peas due to processing and to compare these data according to geographic origin and crop. Six batches of snow peas from two different regions (raw and cooked for 5 min), three batches of garden peas (raw and cooked for 7 min), two batches of canned peas (processed and raw material) and three batches of dry peas (raw and cooked for 35 min) were analyzed. Water content in snow peas differed between crops and region and, in garden peas, it increased after cooking and varied between crops. Cooking caused losses in the ash content of garden and dry peas. In canned peas, processing increased water and ash contents due to absorption of water and salt. Lutein, β-carotene and traces of violaxanthin were identified in all samples. Carotenoids profile of snow, garden and dry peas did not change after cooking while canning caused an apparent increase in lutein contents only in one batch. Snow, garden and dry peas showed differences in lutein and β-carotene amount due to crops, though different regions revealed not to influence snow peas carotenoids content. The raw material from two suppliers of canned peas differed in their content of lutein. Only β-carotene is a pro-vitamin A carotenoid, however it was found in such small quantities that peas can not be considered source of this nutrient.

Amongst the polar organic compounds occurring in unrefined and refined crude oils and the associated polluted production waters, complex mixtures of acids, known historically as naphthenic acids (NAs), have achieved prominence. This is particularly because NAs have been designated a toxicant class of concern in the oil sands process-affected water (OSPW) that has accumulated in vast quantities following exploitation of the oil sands of Northern Alberta, Canada in recent years. However, though there have been calls for NAs to be added to pollutant inventories, at the initiation of the current study, little knowledge existed of the exact composition of refined or unrefined NAs. The overall aim of the current study was therefore to identify individual NAs in refined (commercial) and unrefined (e.g. oil sands process-derived) complex mixtures of acids and then to assess the toxicity of any identified NAs. Individual NAs were tentatively identified by interpretation of the electron ionisation mass spectra of methyl ester derivatives, following comprehensive multidimensional gas chromatography-mass spectrometry (GCxGC-MS). Reference acids were then either purchased, or more commonly, where they were not commercially-available, synthesised, mainly by micro-hydrogenation methods, for co-chromatography and comparison of mass spectra of methyl esters with those of unknowns. The synthetic NAs, purified to >97% were then subjected to toxicological assessments using the Microtox™ assay. In all, 34 compounds were obtained pure enough for testing. Microtox results revealed that the toxicity endpoint (50% Inhibition Concentration, IC50) was between 0.004 and 0.7 mM. Exponential and other correlations were noted between carbon number and toxicity in several of the structural groups of acids assayed, which may be beneficial for predictions of toxicity of non-synthesised acids. Although n-hexanoic acid (IC50 0.7 mM) had the lowest toxicity, adamantane-type acids were the least toxic as a group overall. Conversely, the decahydronaphthalene (decalin)-type acids had the largest range of toxicities (IC50 0.004 to 0.3 mM) and the most toxic acid assayed was 3-decalin-1-yl-propanoic acid. According to USEPA guidelines many individual acids can be said to show low to medium toxicity. Since the acids in commercial and unrefined NAs occur in complex mixtures, an attempt was also made to assess mixture toxicity. Mixtures of individual structural groups of acids (e.g. acyclic isoprenoid acids, n-acids) and a mixture of all 34 acids were assessed. Apart from the adamantane sub-group of acids, all of the mixtures showed toxicities lower than the sum of the parts when calculated using equations for Concentration Addition and Model Deviation Ratios (simply the predicted IC50/Observed IC50). A hypothesis that achievement of a critical micelle concentration is required to produce toxicity was proposed to explain the lower than expected results. Some of the mass spectra of NA present in the commercial and unrefined mixtures were inconsistent with those of any of the alicyclic acids synthesised or purchased. These were hypothesised to be aromatic acids. Fractionation experiments of the NA mixtures using silver ion thin layer chromatography and solid phase extraction (Ag+TLC and Ag+SPE) were carried out in order to provide further evidence for aromatic acids. Ag+TLC allowed separation of a methylated NA mixture from OSPW into three distinct fractions; Ag+SPE resulted in eleven fractions, through the use of a wider range of solvents and differential solvent ratios. Analysis of the fractions by GC-MS revealed that each fraction was largely still made up of unresolved acids (as esters), although one or two fractions revealed some resolved acids. Use of averaged mass spectra and mass chromatography on each fraction revealed further resolved chromatographic peaks and associated interpretable mass spectra. Each of eight of the eleven sub-fractions were examined by GC-MS, in some cases by GCxGC-MS, and all by infrared spectroscopy, ultraviolet visible spectrophotometry and elemental analysis. A number of structures were proposed for the aromatic acids, including those with sulphur-containing moieties. It was noted that far from being minor components, aromatic acids comprised ca.25-40% of the OSPW acid extracts.

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