Orientadores: Pedro Eduardo de Felicio, Jana Pickova / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-04T20:04:37Z (GMT). No. of bitstreams: 1 LapaGuimaraes_Judite_D.pdf: 14813702 bytes, checksum: ceaf92aa9f32ece3f3b4c5ef620aa4ee (MD5) Previous issue date: 2005 / Resumo: Em função da alta perecibilidade do pescado, a avaliação do frescor e qualidade deste alimento deve ser precisa e baseada em métodos consolidados. Bases nitrogenadas voláteis (BNV), trimetilamina (TMA), aminas biogênicas, nucleotídeos, uréia e triptofano livre têm sido propostos como índices de frescor para pescado e podem ser efetivos ou não dependendo da espécie de pescado, microbiota contaminante e condições de armazenamento. A quantificação dos teores de aminas biogênicas é também importante devido ao seu potencial tóxico. Os objetivos deste estudo foram avaliar a utilidade das aminas biogênicas, BNV, TMA, triptofano livre e uréia como índices de qualidade e frescor em peixes e moluscos cefalópodes, desenvolver e avaliar sistemas de solventes para separação de aminas biogênicas por cromatografia de camada delgada e avaliar o efeito do tempo e temperatura de derivatização sobre a conversão das aminas biogênicas em seus derivados dansilados. Derivados dansilados de agmatina (AGM), putrescina (PUT), triptamina (TRY), cadaverina (CAD), histamina (HIS), espermidina (SPD), espermina (SPM), tiramina (TYR) e feniletilamina (PHE) foram separados utilizando-se o sistema de solventes clorofórmio: éter dietílico: trietilamina (6:4:1 - v/v) seguido de clorofórmio: trietilamina (6:1 ¿ v/v). A melhor condição para derivatização das aminas biogênicas com cloreto de dansila foi 1h a 40oC. AGM permaneceu no local de aplicação (RF=0,0), o que indica que a metodologia deve ser utilizada com cautela para a determinação desta amina. As percentagens de recuperação de TRY, SPM, SPD e TYR foram baixas, indicando que a metodologia para extração destas aminas deve ser aperfeiçoada. BNV e TMA foram consideradas índices de frescor inadequados para bacalhau (Gadus morhua) e hadoque (Melanogrammus aeglefinus). O padrão de produção mais acentuado a partir da segunda semana de armazenamento, caracterizou as aminas voláteis e as aminas biogênicas CAD e PUT como índices de deterioração para bacalhau e hadoque. Uréia se mostrou inadequada como índice de qualidade para as duas espécies de pescado estudadas. Modelos de regressão linear e quadrática indicaram um aumento progressivo dos teores de AGM em lula (Illex coindetii), de uréia em sépia (Sepia officinalis), e de BNV e triptofano livre nas duas espécies de cefalópodes desde o início do armazenamento. BNV e triptofano livre foram considerados bons índices de frescor para I. coindetii e S. officinalis, pois seus teores aumentaram significativamente (p<0,05) desde o início do armazenamento. AGM e uréia foram consideradas índices de deterioração para I. coindetii e S. officinalis, respectivamente. Os teores de TMA (% NNP) aumentaram significativamente (p<0,05) durante a primeira semana de armazenamento em I. coindetii o que sugere sua utilidade como índice de frescor para lula. Para S. officinalis TMA é mais adequada como índice de deterioração / Abstract: Fish and shellfish muscle is highly susceptible to spoilage during storage. Because quality quickly decreases during storage reliable chemical indices for quality and freshness evaluation are greatly needed. Total volatile bases-nitrogen (TVB-N), trimethylamine (TMA), biogenic amines, nucleotides, urea and free tryptophan have been suggested as freshness indices for fish and shellfish. Such indices are useful depending on the species, microbial flora and storage conditions. Biogenic amines levels are also cause of concernment due to their toxicological effects. The objectives of this study were to evaluate the usefulness of biogenic amines, TVB-N, TMA, free tryptophan and urea as freshness and quality indices for fish and cephalopods; to develop and evaluate solvent systems for biogenic amines separation by thin-layer chromatography; and to evaluate the effects of time and temperature of derivatisation on the conversion of biogenic amines to their dansyl derivatives. Dansyl derivatives of agmatine (AGM), putrescine (PUT), tryptamine (TRY), cadaverine (CAD), histamine (HIS), spermidine (SPD), spermine (SPM), tiramine (TYR) and phenylethylamine (PHE) were separated using the solvent system chloroform: diethyl ether: triethylamine (6:4:1 ¿ v/v), followed by chloroform: triethylamine (6:1 ¿ v/v). The best dansylation condition was 1h at 40oC. AGM remained at the start position, indicating the determination of AGM by this method should be considered with caution. The percentages of recovery of TRY, SPM, SPD and TYR were low, indicating that the extraction methodology must be improved. TVB-N and TMA were considered inappropriate as freshness indices for cod (Gadus morhua) and haddock (Melanogrammus aeglefinus). CAD and PUT showed the greatest increases during the storage, but their levels did not increase significantly (p<0.05) during the first week. Volatile amines and biogenic amines were characterized as spoilage indices for G. morhua and M. aeglefinus due to the intense increasing of their amounts from the second week of storage. Urea was not useful as a quality index for cod and haddock. Linear and quadratic models indicated progressive increasing of AGM levels in squid (Illex coindetii), urea in cuttlefish (Sepia officinalis) and also increasing of TVB-N and free tryptophan in both cephalopods, since the beginning of the storage. TVB-N and free tryptophan were considered good freshness indices for both cephalopod species, because their levels significantly increased (p<0.05) during the first week of storage. AGM and urea were useful as spoilage indices for I. coindetii and S. officinalis, respectively. It was observed a significant increase of TMA (% of NNP) during the first week of storage in I. coindetii indicating the TMA usefulness as freshness index for squid. For S. officinalis TMA was a good spoilage index / Doutorado / Doutor em Tecnologia de Alimentos

Vanillin (4-hydroxy-3methoxybenzaldehyde) is one of the most employed aromatic and flavoring additives in food and cosmetic industry. The industrial interest in vanillin could also apply to its biodegradation products. The microbial transformation of vanillin can open the possibility of new products with new areas of application for products related to vanillin. For example, vanillyl alcohol, vanillic acid and ferulic acid are currently used in the pharmaceutical or food industry. Some species reported to biodegrade vanillin into the related products vanillyl alcohol and vanillic acid, are: Brettanomyces anomalus and Saccharomyces cerevisiae. Moreover, certain microorganisms possess the ability to accumulate lipids when cultivated on different carbon sources, opening the possibility of microbial lipid production as another industrial application. The present investigation focuses on the optimization of extraction methods for vanillin biodegradation products, as well as identifying the isolates of a collection of microorganisms originating from the Faroe Islands that are amenable to being cultivated on a lignin-based media. Finally, the potential for microbial lipid accumulation was also studied. Two analytical methods, Thin-Layer Chromatography (TLC) and Gas Chromatography (GC) were employed for characterizing the biodegradation products obtained after 24 hours and 72 hours of culture in growth medium supplemented with 1 mM of vanillin. The results showed that after 24 hours of incubation, the model microorganism, strain FMYD002, had consumed some of the vanillin and transformed it into biodegradation products. TLC retention factors and GC chromatograms revealed that the main biodegradation product after 24 hours - when compared to a standard – is likely to be to vanillyl alcohol. Furthermore, vanillin and its biodegradation products were relatively temperature-stable based on a temperature test of supernatant from a 24-hour culture, however, when the 72-hour culture had been subjected to the highest temperature (60 °C) some spontaneous decomposition occurred. The biodegradation pattern of the 72-hour culture evidenced by TLC revealed two additional biodegradation products, one of which migrates in a similar fashion to vanillic acid. After 72 hours of incubation, the biodegradation product presumed to be vanillyl alcohol was no longer observed. Acidification tests showed that the best route for extraction of the product believed to be vanillyl alcohol is to adjust the extracted sample to a pH of 9. The cultivation test of the isolates in media prepared from different lignin-based residual products showed that 26 out of 60 initial strains grew regardless of the concentration of lignosulfonates and vanillin. Moreover, 17 strains grew in nitrogen-limited medium. Eight of the strains accumulated lipids. A preliminary categorization of isolates based on their colony morphology and capacity of growth on different substrates showed that to some extent, their morphology can predict the ability to grow on lignin- and vanillin-based media. This could help future scientists to easily screen for and select isolates with interesting activity for the ligno-cellulose industry.

The chemical profiling, characterization of Aloe products and phytochemical properties of Aloe vera were studied. The adulteration of commercial products derived from medicinal plants has been a major muddle for both the society and the pharmaceuticalindustry. Economically motivated adulteration includes the potential for contaminated, sub‐potent or counterfeit medication to enter the supply chain at several levels, from the production of raw ingredients through to the point of retail sale. Darwin’s theory of evolution states that, species undergo genetic variation with time to adapt to environmental changes. Therefore, the same species growing in widely different habitats may drift from the original genetic makeup as a mechanism of adaptation and that may result in them having different chemical profiles. Therefore this study aimed at investigating the phytochemical properties of Aloe vera growing in South Africa. Also, this study aims to utilize Thin Layer Chromatography to profile this plant, as well as use Infra Red spectroscopy to characterize commercial Aloe vera products. A large quantity of Aloe vera plant was collected from AloeWay, Iphofolo Game Farm, Polokwane in the Limpopo province of South Africa. The identity of the plant was confirmedrom literature and authenticated by Professor DS Grierson of Botany Department, University of Fort Hare, Alice. The plant leaves were divided into two portions. One portion was extracted fresh while the other was cut into pieces and oven dried at 400C then and milled to a homogenous powder once dried completely. The phytochemical composition of the gel and leaf extracts revealed the presence of alkaloids, flavonoids, saponins, tannins and phenols at different concentrations. Results showed that the dry plant material yielded more phytochemicals than the fresh plant material. In particular, it was found that the acetone extract showed much more amounts ofphychemicals than the dichloromethane and aqueous extracts. The percentage compositions of phenols (71.86), flavonols (36.61), proanthocyanidins (82.71), saponins (37.73) and alkaloids (13.29) were significantly high in the acetone extract, followed by the dichloromthane extract with values of 46.85, 37.73, 49.51, 89.0 and 11.11 respectively, while the least composition was found in the aqueous extract. Furthermore, flavonoids were somewhat high in composition in both the aqueous extract of the dried and of the fresh plant material while others were very low. Tannins levels were significantly very low in all the solvent extracts. It was found that the acetone extract showed great amounts of phytochemicals than dichloromethane and aqueous extracts. Since A. vera is used in the treatment of different ailments such as skin wounds and abrasions, eczema, constipation, rheumatoid arthritis etc, the medicinal uses of this plant could be associated to such analysed bioactive compounds. Acetone, hexane, ethanol, water and dichloromethane were used to extract the Aloe vera leaf and the best solvent extract was determined. Thin layer chromatography was used to profile the leaf extracts with the aim of documenting the main phytochemicals present in the Aloe vera growing in South Africa. The best spraying reagent was determined. Fourier transform infrared spectrophotometer was used to validate the presence of Aloe vera ingredients in commercial products. The yield extraction ability of the solvent was the order: water>ethanol> hexane >dichloromethane and acetone for the dry portion. However, for the plant extracted fresh, the order of yield produced was ethanol-acetone-dichloromethane > and water. The different solvent systems separated the compounds differently. Hexane: acetone: ethanol (20 : 5: 2) and Benzene: ethanol: ammonium (80): ethanol (10): ammonium solvent systems were noted to be the best mobile phase as they gave the best separation compared to other systems.EMW [ethyl acetate (81): methanol (11): water (8)] showed better separation than the other two separating solvent systems. Vanillin- sulphuric acid spray was seen to be the best spraying reagent as compared to vanillin- phosphoric acid. Fourier transform infrared spectrophotometer validated the presence aloe ingredients in aloe vera commercial products.

This dissertation describes advances in the microfabrication of thin layer chromatography (TLC) plates. These plates are prepared by the patterning of carbon nanotube (CNT) forests on substrates, followed by their infiltration with an inorganic material. This document is divided into ten sections or chapters. Chapter 1 reviews the basics of conventional TLC technology. This technology has not changed substantially in decades. This chapter also mentions some of the downsides of the conventional approach, which include unwanted interactions of the binder in the plates with the analytes, relatively slow development times, and only moderately high efficiencies. Chapter 2 focuses primarily on the tuning of the iron catalyst used to grow the CNTs, which directly influences the diameters of the CNTs grown that are produced. Chapter 3 focuses on the atomic layer deposition (ALD) of SiO2 from a silicon precursor and ozone onto carbon-nanotubes to obtain an aluminum free stationary phase. This approach allowed us to overcome the tailing issues associated with the earlier plates prepared in our laboratory. Chapter 4 is a study of the hydroxylation state of the silica in our TLC plates. A linear correlation was obtained between the SiOH+/Si+ time-of-flight secondary ion mass spectrometry (ToF-SIMS) peak ratio and the isolated silanol peak position at ca. 3740 cm-1 in the diffuse reflectance infrared spectroscopy (DRIFT) spectra. We also compared the hydroxylation efficiencies on our plates of ammonium hydroxide and HF. Chapter 5 reports a series of improvements in TLC plate preparation. The first is the low-pressure chemical vapor deposition (LPCVD) of silicon nitride onto CNTs, which can be used to make very robust TLC plates that have the necessary SiO2 surfaces. These TLC plates are the best we have prepared to date. We also describe here the ALD deposition of ZnO into these devices, which can make them fluorescent. Chapters 6 – 10 consist of contributions to Surface Science Spectra (SSS) of ToF-SIMS spectra of the materials used in our microfabrication process. SSS is a peer-reviewed database that has been useful to many in the surface community. The ToF-SIMS spectra archived include those of (i) Si/SiO2, (ii) Si/SiO2/Al2O3, (iii) Si/SiO2/Al2O3/Fe, (iv) Si/SiO2/Fe (annealed at 750 °C in H2), and (v) Si/SiO2/Al2O3/Fe(annealed)/CNTs. Both positive and negative ion spectra have been submitted. In summary, the present work is a description of advances in the development, thorough characterization, optimization, and application development of microfabricated thin layer chromatography plates that are superior to their commercial counterparts.

The lipid composition of sperm membranes is crucial for fertilization and differs among species. As the evolution of internal fertilization modes in fishes is not understood, a comparative study of the sperm lipid composition in freshwater representatives of externally and internally fertilizing fishes is needed for a better understanding of taxa-specific relationships between the lipid composition of the sperm membrane and the sperm physiology. The lipidomes of spermatozoa from stingray, a representative of cartilaginous fishes possessing internal fertilization, and sterlet, a representative of chondrostean fishes with external fertilization, have been studied by means of nuclear magnetic resonance (NMR), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), electrospray MS, gas chromatography-(GC) MS, and thin-layer chromatography (TLC). NMR experiments revealed higher cholesterol content and the presence of phosphatidylserine in stingray compared to sterlet sperm. Unknown MS signals could be assigned to different glycosphingolipids in sterlet (neutral glycosphingolipid Gal-Cer(d18:1/16:0)) and stingray (acidic glycosphingolipid sulpho-Gal-Cer(d18:1/16:0)). Free fatty acids in sterlet sperm indicate internal energy storage. GC-MS experiments indicated a significant amount of adrenic acid, but only a low amount of docosahexaenoic acid in stingray sperm. In a nutshell, this study provides novel data on sperm lipid composition for freshwater stingray and sterlet possessing different modes of fertilization.

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No description available.

Surfaces that exhibit a gradual change in their chemical and/or physical properties are termed as surface gradients. Based on the changes in properties they are classified either as physical or chemical gradients. Chemical gradients show variations in properties like polarity, charge, functionality concentration and have found potential applications in fields of biology, physics, biosensing, catalysis and separation science. In this dissertation, surface gradients have been prepared using controlled rate infusion (CRI). CRI is a simple method in which a surface gradient is formed by carrying out the infusion of organoalkoxysilane in a time-dependent fashion using a set infusion rate. Depending on concentration of silane, rate of infusion and time of infusion, the gradient profiles on surfaces can be varied and the surface chemistry of the substrate can be altered. Initial work in the dissertation focuses on demonstrating different gradient profiles and selectivity obtained using amine and/ or phenyl functionalized gradient stationary phases on thin layer chromatography (TLC) plates prepared by CRI. The presence of amine and phenyl on the surfaces were confirmed by X-ray Photoelectron Spectroscopy (XPS) and diffuse reflectance spectroscopy, respectively. The change in surface chemistry was demonstrated by changes in the selectivities of water and fat soluble vitamins. After successful preparation and characterization of single and multi-component stationary phase gradients for planar chromatography, single-component gradients were prepared for column chromatography (Silica monolithic columns). Similar to that observed for planar chromatography, the selectivity was evaluated from retention factors and was found to be different for a weak acid/weak base mixture. The results obtained showed the promising approach of using gradient stationary phases in column chromatography. This work was further extended to prepare amine and phenyl multi-component gradients on silica monolithic columns to investigate mixed-mode and synergistic effects. Finally, amine, phenyl and thiol gradients were also prepared on cellulose substrates, particularly water color paper, The goal was to study the formation of functionality gradients on cellulose substrates particularly the interaction between hydroxyl groups on cellulose and silanols and to study the stability of the silanes on the cellulose surface.

Palicourea marcgravii St. Hil. (Rubiaceae) vulgarmente conhecida como \"erva de rato\" é uma planta tóxica brasileira de grande interesse econômico na pecuária, por provocar, em bovinos, convulsões, arritmias cardíacas e \"morte súbita\" em elevado número de animais. No presente trabalho, as folhas dessecadas e moídas de P. marcgravii foram extraídas com etanol 95 %, a temperatura ambiente, por percolação; o extrato resultante foi fracionado por partição com acetato de etila e butanol saturado com água. Os resíduos obtidos foram testados \"per os\" em ratos, buscando-se investigar nos mesmos, a presença do princípio ativo tóxico. O resíduo aquoso foi o único que produziu convulsões e morte dos animais. A existência do monofluoroacetato (MF A) no resíduo aquoso foi comprovada biologicamente através do paralelismo entre as retas refetentes às funções dose/porcentagem de letalidade e dose/latência para a 1&#170; convulsão que foram construídas para o resíduo aquoso e padrão de referência (monofluoroacetato de sódio). O MFA foi também identificado quimicamente através da RMN19F e da cromatografia em camada delgada. Os resultados obtidos comprovaram a presença de MF A nas folhas de P.marcgravii, responsabilizando-o pelos efeitos tóxicos produzidos. Também foram levantadas algumas hipóteses na tentativa de explicar a sintomatologia dos animais intoxicados. / Palicourea marcgravii St. Hil. (Rubiaceae) is one of the most economica1ly important poisonous plants for Brazilian livestock, since it induces not only seizures, cardiac arrythmias, but also \"sudden death\" of large number of the intoxicated animals. ln the present paper, the dissected and grounded leaves of P.marcgravii were extracted with ethanol 95 %, at room temperature, by percolation; the resultant extract was fractionized by partition in ethyl acetate and butanol saturated with water. The obtained residues were administered \"per os\" to rats, trying to look for the presence of the active toxic principIe. The aqueous residue was the only that induced seizures and death to the animals. The presence of monofluoroacetate (MFA) in the aqueous residue was biologica1ly confirmed by the correlation shown in the sodium monofluoroacetate and the aqueous residue dose-response and dose effect curves. MFA was also identified through NMR19F and thin layer chromatography. The obtained results confirmed the presence of MF A in the P.marcgravii leaves; they also suggest that the toxic effects induced by this plant are a consequence of the presence of MFA in its leaves. Further, some hypothesis were also perfomed, in an attempt to better explain the symptoms induced by the plant leaves.

A atual Política Nacional de Plantas Medicinais e Fitoterápicos prevê investimentos em pesquisa e desenvolvimento para suprir a necessidade da indústria nacional em adquirir a matéria prima para a produção de novos fitoterápicos de maneira segura e controlada. As espécies do gênero Smilax, conhecidas popularmente como salsaparrilha, são empregadas na medicina popular como fortificante, antirreumático e antissifilítico e são vendidas em farmácias, casa de ervas e mercados públicos sem que exista um controle de qualidade de sua origem e eficácia. Além disso, a procedência do material é baseada principalmente no extrativismo. O controle de qualidade das drogas vegetais deveria ter uma base mais segura de identificação das drogas através da caracterização e definição de particularidades anatômicas e químicas. Este estudo teve como objetivo apresentar a quantidade, o valor, o modo de preparo, utilização e a procedência da salsaparrilha comercializada no Estado de São Paulo, bem como analisar a anatomia e o perfil químico de 44 amostras de salsaparrilha comercializada. Amostras de raiz foram submetidas às técnicas convencionais de microscopia de luz e eletrônica de varredura. Também foram realizados testes histoquímicos. Para determinar o perfil químico por Cromatografia em Camada delgada (CCD), foram realizados extratos etanólicos de amostras de raízes. O perfil químico do material comercializado foi comparado com o perfil das espécies de Smilax previamente identificadas (S. goyazana A. De Candolle, S. rufescens Grisebach, S. brasiliensis Sprengel, S. campestris Grisebach, S. cissoides Martius ex Grisebach, S. fluminensis Steudel, S. oblongifolia Pohl ex Grisebach e S. polyantha Grisebach). A quantidade média de salsaparrilha comercializada nas farmácias (400g) e nas casas de ervas (20Kg) é elevada se for considerado o fato de que as raízes não são procedentes de cultivo. Embora tenha sido observada grande semelhança entre a estrutura anatômica das amostras de salsaparrilha comercializadas e a estrutura já descrita na literatura para as espécies de Smilax, houve diferenças em relação à organização do floema, à presença de séries de idioblastos contendo ráfides na medula, à ausência de idioblastos fenólicos na medula e presença de metaxilema no centro da estrutura. O teste histoquímico confirmou a presença de amido em todas as amostras comerciais. As análises em CCD dos extratos etanólicos das amostras comerciais evidenciaram diversas manchas com tonalidades variando de amarelo a verde. Além disso, as manchas apresentaram componentes de mesmo Fator de retenção (Rf), indicando semelhança química entre as diversas amostras. No entanto, o padrão de distribuição de manchas, bem como o Rf das amostras comerciais diferiu daqueles obtidos para as oito espécies de Smilax, os quais foram muito similares entre si. / The current National Policy on Herbal Medicine provides investments in drug research and development to supply the need of national industry to acquire the raw material for production new herbal medicines in a safe and controlled way. The species of Smilax, popularly known as sarsaparilla, are used in folk medicine to be effective as tonic, antirheumatic and antisyphilitic properties and they are commercialized in pharmaceutical stores, natural products stores and public markets in Brazil with no quality control of its origin and efficacy. In addition, these plants are still harvested in extractive way. The quality control of herbal drugs should have more secure identification of drugs through the characterization and definition of anatomical and chemical peculiarities. This study aims to present the quantity, value, method of preparation, use and origin of the commercialized sarsaparilla in cities from the São Paulo state and to investigate the anatomy and chemical profile of 44 samples of the commercialized sarsaparilla. Root samples were processed and analyzed using conventional light and scanning electron microscopy techniques. Usual histochemical tests were also performed. Chemical profiles of samples were analyzed by thin layer chromatography (TLC) using ethanolic extracts of the roots. The chemical profile of the commercialized material was compared with profiles of previously identified species of Smilax (S. goyazana A. De Candolle, S. rufescens Grisebach, S. brasiliensis Sprengel, S. campestris Grisebach, S. cissoides Martius ex Grisebach, S. fluminensis Steudel, S. oblongifolia Pohl ex Grisebach and S. polyantha Grisebach). The average amount of sarsaparilla sold in pharmaceutical stores (400g) and natural products stores (20kg) is high if one considers the fact that the roots are not found under cultivation. Although there was a great similarity between the anatomical structure of commercialized sarsaparilla and the structure already described in literature for the Smilax species, there were found some differences in the organization of the phloem, the occurrence of series of idioblasts containing raphides in the pith, the absence of phenolic idioblasts in the pith and the presence of metaxylem in the center of the organ. The histochemical tests confirmed the presence of starch in all commercialized samples. Chemical profile showed several spots with colors ranging from yellow to green. Moreover, the spots showed the same components retention factor (Rf), indicating chemical similarity between the different samples. However, the distribution pattern of spots, Rf value of commercial samples differed from the eight species of Smilax, which were very similar to each other.