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Pharmaceutical analysis and in-vitro aerodynamic characterisation of inhaled theophylline formulations containing drug particles prepared by supercritical fluid processing. Chromatographic, spectroscopic, and thermal analysis of micron-sized theophylline particles prepared by supercritical fluid technology and in-vitro evaluation of their performance as inhaled dry powder formulations.Mohamed, Noha N.A. January 2009 (has links)
The aim of this work is to study the in-vitro aerodynamic performance of a new inhaled theophylline formulation prepared by supercritical fluids technique.
For the analysis of the output from the in-vitro tests (and further in-vivo tests) a new, fast, sensitive high performance liquid chromatographic (HPLC) method was developed and validated for the determination of theophylline and other related derivatives in aqueous and urine samples using new packing materials (monolithic columns). These columns achieve efficient separation under lower backpressure and shorter time comparing to other traditionally or newly introduced C18 columns.
Solution enhanced dispersion by supercritical fluid (SEDS) process has been applied for the production of anhydrous theophylline as pure crystals in the range 2-5 ¿m to be used as new inhaled dry powder formulation for asthma. Fifteen theophylline samples have been prepared under different experimental conditions.
The drug produced by this method has been subject to a number of solid-phase analytical procedures designed to establish the crystal structure [X-ray powder diffraction (XRPD)], the structure and conformation [(FTIR), Fourier-transform Raman spectroscopy (FT-Raman)], and the morphology and particle size [scanning electron microscope (SEM)]. While, thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC) have been used to monitor any phase transition or polymorphic changes after processing. All these analytical techniques gave a satisfactory indication of the solid-state chemistry of the processed particles and assess the development of new inhalation product.
The performance of inhaled SEDS theophylline with or without a carrier was evaluated using the developed HPLC method. Three samples having different particle sizes were selected out of the prepared powders by SEDS technique to be tested. The dose sampling unit and the Anderson Cascade Impactor were used to determine the in-vitro emitted dose and the deposition profiles of SEDS samples, respectively. The effect of different inhalation flows was studied using two different flows 28.3, and 60 L min-1 with 4 L inhalation volume. Different DPI devices were investigated in this study; Easyhaler® and Spinhaler®. The particle size has an important effect on the aerodynamic behaviour and deposition profile of inhaled drug, the smaller the particles the greater the total lung deposition. The presence of a carrier improves the respirable fraction for all the tested formulations. / Egyptian Ministry of Higher Education
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Modulation of Spontaneous Neural Network Bursting in Newborn Rat Brain Slices by Extracellular Calcium, Methylxanthines, and OpioidsKantor, Chase M Unknown Date
No description available.
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Isolamento de constituintes e síntese de flavonoides encontrados em Poincianella pyramidalis (Fabaceae) e análise fitoquímica de Theobroma cacao (Malvaceae)Oliveira, José Cândido Selva de January 2014 (has links)
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TESE COMPLETA.pdf: 4364010 bytes, checksum: db848addf66479f547ccb64d058e01e0 (MD5) / CNPq e CAPES / Os extratos MeOH de Poincinella pyramidalis (caatingueira), obtidas da casca da raiz
(PPCR) e das flores (PPF), bem como, as frações orgânicas obtidas por partição, foram
submetidas a testes de atividade citotóxica, antioxidante e anticolinesterásica. O teste
citotóxico contra Artemia salina revelou atividade moderada para fase AcOEt em
PPCR. Assim como, a fase AcOEt de PPCR apresentou 75% de inibição no teste
anticolinesterásico. Para a atividade antioxidante, as fase AcOEt e BuOH de PPF foi a
mais ativa, sendo atribuída a presença de galato de metila (PPF3). Por meio de
processos cromatográficos foi possível isolar da fase DCM de PPF as substâncias PPF1
(alcoóis graxos), PPF2a-b (β–sitosterol/estigmasterol), PPF3 (galato de metila) e PPF4
(α e β–amirina). Além dessas, foram isoladas da fase hexano de PPCR ésteres metílicos
(PPCR1) e o biflavonoide 5,7-dihidroxi-4´-metoxiflavona-6α-2´´´,4´´´-dihidroxi-4´´-
metoxidihidrochalcona (PPCR3). Da fase hidroMeOH de PPCR foram isoladas as
substâncias PPCR2 (ácido 3,3´-dimetoxi-4-hidroxielagico-4´-β-D-xilopiranosideo) e
outro biflavonoide PPCR4 (5-hidroxi-7,4´-dimetoxiflavona-3α-2´´´-hidroxi-4´´´,4´´-
dimetoxidihidrochalcona). Sendo PPCR3 e PPCR4 inéditas na literatura. O extrato
hexano de Theobroma cacao (cacau) obtido das sementes (STC) foi analisado por RMN
e revelou presença de triacilglicerideos. A otimização e fracionamento do extrato
MeOH de T. cacao utilizando CCC levou ao isolamento simultâneo de teobromina (2),
teofilina (3) e cafeína (4), fase móvel hexano:AcOEt (2:3) e estacionária MeOH:H2O
(1:1). Um método analítico foi desenvolvido empregando HPLC/DAD com coluna fase
reversa C-18 para a quantificação de 2, 3 e 4 nos extrativos em fase ácida/básica e nas
frações STC6-22 e STC23-67 obtidas por CCC. Assim, os teores de 2 e 4 para no
extrato MeOH de T. cacao e frações obtidas por CCC foram determinados. A teofilina
(3) detectada e quantificada na fração STC6-22 em baixa concentração (0,78 mg/g) em
relação a 2 e 4. A apigenina (6) foi sintetizada utilizando dois métodos distintos (“A” e
“B”). O metodo “B” apresentou rendimento de 74% em uma única etapa. A síntese de
derivados O-metilados forneceu bons rendimentos (> 90%). As substâncias
isoladas/sintetizadas foram submetidas à atividade anticolinesterasica do qual, são
inativas. As mesmas foram elucidadas a partir de dados de IV, UV, EM, α[D], RMN de
1H e 13C (BB e APT), RMN de correlação (HMQC, HSQC e HMBC). / The MeOH extracts from Poincinella pyramidalis (caatingueira), obtained of bark root
(PPCR) and flowers (PPF), as well the organic fractions obtained by partition, have
been tested for cytotoxicity, antioxidant and anticholinesterasic activity. The cytotoxic
test against Artemia salina showed moderate activity for AcOEt phase in PPCR. Well
the EtOAc phase of PPCR showed 75% inhibition on anticholinesterasic test. For the
antioxidant activity, the EtOAc and BuOH phase of PPF was the most active, being
attributed to the presence of methyl gallate (PPF3). For chromatographic process was
possible to isolate the DCM phase of PPF the substances PPF1 (fatty alcohols), PPF2a-
b (β–sitosterol/stigmasterol), PPF3 (methyl galate) and PPF4 (α- and β–amirin).
Besides these, were isolated from the hexane phase PPCR methyl esters (PPCR1) and
the biflavonoid 5,7-dihidroxy-4´-methoxyflavone-6α-2´´´,4´´´-dihidroxy-4´´-methoxy
dihidrochalcone (PPCR3). The HidroMeOH phase of PPCR were the isolated
substances PPCR2 (3,3´-dimethoxi-4-hidroxyellagicacid-4´-β-D-xylopiranoside) and
other biflavonoid PPCR4 (5-hidroxy-7,4´-dimethoxyflavone-3α-2´´´-hidroxy-4´´´,4´´-
dimethoxydihidrochalcone). Being PPCR3 and PPCR4 unpublished in literature.
Hexane extract of Theobroma cacao (cacau) obtained from the seeds (STC) was
analyzed by NMR and revealed the presence of triacylglycerides. The optimization and
fractionation of MeOH extract of T. cacao using CCC led to the simultaneous isolation
of theobromine (2) Theophylline (3) and caffeine (4), mobile phase hexane:EtOAc (2:3)
and stationary MeOH:H2O (1:1). An analytical method was developed employing
HPLC/DAD with reverse phase column C-18 for the measurement of 2, 3 and 4 in the
extractives acid/base phase and the STC6-22 and STC23-67 fractions obtained by
CCC. So, the levels of 2 and 4 for the MeOH extract of T. cacao and fractions obtained
by CCC were determined. Theophylline (3) detected and quantified in the fraction
STC6-22 low concentration (0.78 mg/g) in relation the 2 and 4. Apigenin (6) was
synthesized using two different methods ("A" and "B"). The method "B" had a yield of
74% in one step. The synthesis of O-methylated derivatives provided good yields (>
90%). The isolated/synthesized substances were submitted to anticholinesterasic activity
which are inactive. The same were elucidated from data of IR, UV, MS, α[D], 1H NMR
and 13C NMR (BB and APT) NMR correlation (HMQC, HSQC and HMBC).
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Teofilina associada ou não à heparina como agente capacitante para produção in vitro de embriões bovinos / Theophylline with or without heparin as agent empowering for in vitro production of bovine embryosSilva, Laíla Pereira da 27 February 2015 (has links)
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Previous issue date: 2015-02-27 / Fundacao de Amparo a Pesquisa do Estado de Minas Gerais / The in vitro production (IVP) of bovine embryos despite already used on a commercial scale, presents high variability in the results, that can often be attributed to the fertilization step. Therefore, it is important to research factors related to semen, such as sperm capacitation process. The aim of the study was to evaluate theophylline or its combination with heparin as possible replacement capacitation agent in the development of in vitro produced embryos and in acrosome reaction of sperm cells. The experiment was carried out with 4 bulls and 3 treatments, with 12 experimental groups. Each bull was evaluated in all treatments as described below: Treatment 1 (T1): Heparin - 10mg / ml; Treatment 2 (T2): Theophylline - 5 mM; Treatment 3 (T3): Heparin (10 mg / ml) + theophylline (5mM). The bulls semen was thawed and exposed to incubation in three treatments for 0, 6, 12 and 18h, subsequently stained with Trypan blue / Giemsa and analyzed by electron microscopy for assessment of the acrosome reaction. For IVP of embryos capacitation agents added to fertilization medium were evaluated utilizing the same bulls. In sperm analysis, real acrosome reaction rate was higher (p<0,05) at 0h time while the higher dead spermatozoa rate (p<0,05) was observed at 12 h (84,46 ± 5,82 ) and 18h (86,75 ± 4,19). The IVP embryos rate (37,97 ± 13) and the hatching rate (33,50 ± 14) were higher (p<0,05) in heparin treatment. There was no influence of bull or treatments (p> 0.05) in the acrosome reaction analysis. The use of theophylline as a capacitation agent decreased embryo production rates in IVF, however was as efficient as heparin in acrosome reaction induction. / A produção in vitro de embriões (PIVE) bovinos, apesar de já utilizada em escala comercial, apresenta elevada variabilidade em seus resultados, que pode frequentemente ser atribuída à etapa de fertilização. Sendo assim, torna-se importante o estudo dos fatores relacionados ao sêmen, como o processo de capacitação espermática. O objetivo do estudo foi avaliar a teofilina como agente de capacitação substituto ou associado à heparina no desenvolvimento de embriões produzidos in vitro e sobre a reação acrossômica das células espermáticas. O experimento foi realizado com 4 touros e 3 tratamentos, totalizando 12 grupos experimentais. Cada touro foi avaliado em cada tratamento descrito a seguir: Tratamento 1 (T1): Heparina - 10µg/mL; Tratamento 2 (T2): Teofilina 5 mM; Tratamento 3 (T3): Heparina (10µg/mL) + Teofilina (5mM). O sêmen dos touros foi descongelado e submetido à incubação com os três tratamentos por 0, 6, 12 e 18h, posteriormente corados com Trypan blue/ Giemsa e analisados em microscopia eletrônica para avaliação da reação acrossômica. Para a PIVE os agentes de capacitação adicionados aos meios de fertilização foram testados utilizando os mesmos touros. Na análise espermática a taxa de reação acrossômica verdadeira foi maior (p<0,05) no tempo 0h enquanto para os espermatozoides mortos foi observada maior taxa (p<0,05) nos tempos de 12h (84,46 ± 5,82) e 18h (86,75 ± 4,19). A taxa de embriões produzidos na PIVE (37,97 ± 13) e a taxa de eclosão (33,50 ± 14) foram maiores (p<0,05) para o tratamento heparina. Não houve influência de touro ou de tratamentos (p>0,05) na análise de reação acrossômica. A utilização da teofilina como agente de capacitação reduziu as taxas de produção embrionária na fertilização in vitro, no entanto foi tão eficiente quanto à heparina na indução da reação do acrossoma.
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Atividade de frações bioativas de erva-mate (ilex paraguariensis A. St. Hil.) sobre o metabolismo de ratos wistar submetidos à dieta hiperlipídicaResende, Pedro Ernesto de January 2013 (has links)
Ilex paraguariensis A. St. Hil. é uma espécie nativa da América do Sul popularmente conhecida como mate ou erva-mate. Três principais classes de compostos bioativos estão presentes nas folhas: metilxantinas, polifenóis e saponinas, nas quais são atribuídas diversas atividades biológicas, incluindo efeitos no metabolismo lipídico. Do ponto de vista químico e biológico, essa espécie é bastante estudada. Em relação ao processo de obtenção, enriquecimento e purificação das frações do mate, porém, a pesquisa tecnológica revela-se restrita. Este trabalho teve como objetivo avaliar a atividade dos principais grupos de compostos do mate sobre o metabolismo de ratos Wistar submetidos à uma dieta hiperlipídica. A extração de polifenóis, metilxantinas e saponinas das folhas foi otimizado mediante um desenho experimental do tipo Box-Behnken, obtendo-se rendimentos máximos de 357, 41 e 15 mg/g de planta seca, respectivamente. Uma fração enriquecida em polifenóis e metilxantinas (MXPL) e outra enriquecida em saponinas (SFL) foram preparadas por fracionamento em fase sólida de resina polimérica, metanol e água em gradiente decrescente de polaridade. Os rendimentos para polifenóis, metilxantinas e saponinas foram 497, 88 e 245 mg/g de material seco, respectivamente. Vinte quatro ratos Wistar machos foram submetidos a uma dieta hiperlipídica e seis ratos submetidos à uma dieta padrão durante cinco semanas. Posteriormente, foram separados em dois grupos controles (dieta padrão e hiperlipídica), um grupo tratado com extrato de mate (YME), outro tratado com MXPL e outro tratado com SFL. Nenhum aumento significativo no peso corporal em ratos com dieta hiperlipídica foi observado, contudo, houve alterações evidentes em outros parâmetros relevantes relacionados ao metabolismo. Resultados referentes à redução de peso corporal, níveis plasmáticos de glicose e lipogênese se contrapõem a outros antes relatados na literatura, sugerindo uma relação com o modelo animal utilizado. Atividades observadas para o extrato e frações indicam claramente que essas podem ser diferentes e até opostas, levando acreditar que os principais compostos do mate possuam diferentes efeitos no metabolismo quando testados separadamente. / Ilex paraguariensis A. St. Hil. is a South American native species commonly known as mate or yerba mate and is widely used as stimulant tea-like beverages. Methylxanthines, polyphenols and saponins are the main compounds present in its leaves. To these, are attributed several biological activities, including effects in lipid metabolism. Although there are a range of studies of mate, in the point of view of technological processing and biological testing of enriched and purified fractions revealed to be restricted. In this sense, the aim of this study is to evaluate the activity of the main compounds found in mate on the lipid metabolism of male Wistar rats fed with a high-fat diet. For this propose, it was obtained and optimized an extract of mate leaves (YME) by a Box-Behnken design, obtaining maximum yields of 357, 41 and 15 mg/g dry material, respectively. Subsequently, the main compounds were separated by solid phase extraction and fractionation using a polymer resin, methanol and water, in decreasing gradient polarity, achieving an enriched fraction of polyphenol and methylxanthines (MXPL) and an enriched fraction of saponins (SFL). Yields for polyphenols, saponins and methylxanthines were 497, 88 and 245 mg/g of dry material, respectively. Twenty four male Wistar rats were submitted to a high-fat diet and six to a standard diet, during five weeks and separated in five groups (standard diet (control) (n = 6); high-fat diet (n = 6); YME-treated group (n = 6); MXPL-treated group (n = 6); SFL-treated group (n = 6). No significant increase in rats body weight fed with high-fat diet was observed. However, there were evident alterations in fat other relevant parameters related to metabolism. Dissimilar results regarding the reduction of body weight, plasma levels of glucose and lipogenesis, for instance, are opposed to other studies, previously reported in the literature, suggesting that the animal model might be determinant in the evaluation of these activities. Likewise, effects observed in the crude extract and enriched fractions clearly indicate that these may be different, even opposite, leading to believe that the main compounds of mate have different effects on metabolism when are tested separately.
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Atividade de frações bioativas de erva-mate (ilex paraguariensis A. St. Hil.) sobre o metabolismo de ratos wistar submetidos à dieta hiperlipídicaResende, Pedro Ernesto de January 2013 (has links)
Ilex paraguariensis A. St. Hil. é uma espécie nativa da América do Sul popularmente conhecida como mate ou erva-mate. Três principais classes de compostos bioativos estão presentes nas folhas: metilxantinas, polifenóis e saponinas, nas quais são atribuídas diversas atividades biológicas, incluindo efeitos no metabolismo lipídico. Do ponto de vista químico e biológico, essa espécie é bastante estudada. Em relação ao processo de obtenção, enriquecimento e purificação das frações do mate, porém, a pesquisa tecnológica revela-se restrita. Este trabalho teve como objetivo avaliar a atividade dos principais grupos de compostos do mate sobre o metabolismo de ratos Wistar submetidos à uma dieta hiperlipídica. A extração de polifenóis, metilxantinas e saponinas das folhas foi otimizado mediante um desenho experimental do tipo Box-Behnken, obtendo-se rendimentos máximos de 357, 41 e 15 mg/g de planta seca, respectivamente. Uma fração enriquecida em polifenóis e metilxantinas (MXPL) e outra enriquecida em saponinas (SFL) foram preparadas por fracionamento em fase sólida de resina polimérica, metanol e água em gradiente decrescente de polaridade. Os rendimentos para polifenóis, metilxantinas e saponinas foram 497, 88 e 245 mg/g de material seco, respectivamente. Vinte quatro ratos Wistar machos foram submetidos a uma dieta hiperlipídica e seis ratos submetidos à uma dieta padrão durante cinco semanas. Posteriormente, foram separados em dois grupos controles (dieta padrão e hiperlipídica), um grupo tratado com extrato de mate (YME), outro tratado com MXPL e outro tratado com SFL. Nenhum aumento significativo no peso corporal em ratos com dieta hiperlipídica foi observado, contudo, houve alterações evidentes em outros parâmetros relevantes relacionados ao metabolismo. Resultados referentes à redução de peso corporal, níveis plasmáticos de glicose e lipogênese se contrapõem a outros antes relatados na literatura, sugerindo uma relação com o modelo animal utilizado. Atividades observadas para o extrato e frações indicam claramente que essas podem ser diferentes e até opostas, levando acreditar que os principais compostos do mate possuam diferentes efeitos no metabolismo quando testados separadamente. / Ilex paraguariensis A. St. Hil. is a South American native species commonly known as mate or yerba mate and is widely used as stimulant tea-like beverages. Methylxanthines, polyphenols and saponins are the main compounds present in its leaves. To these, are attributed several biological activities, including effects in lipid metabolism. Although there are a range of studies of mate, in the point of view of technological processing and biological testing of enriched and purified fractions revealed to be restricted. In this sense, the aim of this study is to evaluate the activity of the main compounds found in mate on the lipid metabolism of male Wistar rats fed with a high-fat diet. For this propose, it was obtained and optimized an extract of mate leaves (YME) by a Box-Behnken design, obtaining maximum yields of 357, 41 and 15 mg/g dry material, respectively. Subsequently, the main compounds were separated by solid phase extraction and fractionation using a polymer resin, methanol and water, in decreasing gradient polarity, achieving an enriched fraction of polyphenol and methylxanthines (MXPL) and an enriched fraction of saponins (SFL). Yields for polyphenols, saponins and methylxanthines were 497, 88 and 245 mg/g of dry material, respectively. Twenty four male Wistar rats were submitted to a high-fat diet and six to a standard diet, during five weeks and separated in five groups (standard diet (control) (n = 6); high-fat diet (n = 6); YME-treated group (n = 6); MXPL-treated group (n = 6); SFL-treated group (n = 6). No significant increase in rats body weight fed with high-fat diet was observed. However, there were evident alterations in fat other relevant parameters related to metabolism. Dissimilar results regarding the reduction of body weight, plasma levels of glucose and lipogenesis, for instance, are opposed to other studies, previously reported in the literature, suggesting that the animal model might be determinant in the evaluation of these activities. Likewise, effects observed in the crude extract and enriched fractions clearly indicate that these may be different, even opposite, leading to believe that the main compounds of mate have different effects on metabolism when are tested separately.
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Atividade de frações bioativas de erva-mate (ilex paraguariensis A. St. Hil.) sobre o metabolismo de ratos wistar submetidos à dieta hiperlipídicaResende, Pedro Ernesto de January 2013 (has links)
Ilex paraguariensis A. St. Hil. é uma espécie nativa da América do Sul popularmente conhecida como mate ou erva-mate. Três principais classes de compostos bioativos estão presentes nas folhas: metilxantinas, polifenóis e saponinas, nas quais são atribuídas diversas atividades biológicas, incluindo efeitos no metabolismo lipídico. Do ponto de vista químico e biológico, essa espécie é bastante estudada. Em relação ao processo de obtenção, enriquecimento e purificação das frações do mate, porém, a pesquisa tecnológica revela-se restrita. Este trabalho teve como objetivo avaliar a atividade dos principais grupos de compostos do mate sobre o metabolismo de ratos Wistar submetidos à uma dieta hiperlipídica. A extração de polifenóis, metilxantinas e saponinas das folhas foi otimizado mediante um desenho experimental do tipo Box-Behnken, obtendo-se rendimentos máximos de 357, 41 e 15 mg/g de planta seca, respectivamente. Uma fração enriquecida em polifenóis e metilxantinas (MXPL) e outra enriquecida em saponinas (SFL) foram preparadas por fracionamento em fase sólida de resina polimérica, metanol e água em gradiente decrescente de polaridade. Os rendimentos para polifenóis, metilxantinas e saponinas foram 497, 88 e 245 mg/g de material seco, respectivamente. Vinte quatro ratos Wistar machos foram submetidos a uma dieta hiperlipídica e seis ratos submetidos à uma dieta padrão durante cinco semanas. Posteriormente, foram separados em dois grupos controles (dieta padrão e hiperlipídica), um grupo tratado com extrato de mate (YME), outro tratado com MXPL e outro tratado com SFL. Nenhum aumento significativo no peso corporal em ratos com dieta hiperlipídica foi observado, contudo, houve alterações evidentes em outros parâmetros relevantes relacionados ao metabolismo. Resultados referentes à redução de peso corporal, níveis plasmáticos de glicose e lipogênese se contrapõem a outros antes relatados na literatura, sugerindo uma relação com o modelo animal utilizado. Atividades observadas para o extrato e frações indicam claramente que essas podem ser diferentes e até opostas, levando acreditar que os principais compostos do mate possuam diferentes efeitos no metabolismo quando testados separadamente. / Ilex paraguariensis A. St. Hil. is a South American native species commonly known as mate or yerba mate and is widely used as stimulant tea-like beverages. Methylxanthines, polyphenols and saponins are the main compounds present in its leaves. To these, are attributed several biological activities, including effects in lipid metabolism. Although there are a range of studies of mate, in the point of view of technological processing and biological testing of enriched and purified fractions revealed to be restricted. In this sense, the aim of this study is to evaluate the activity of the main compounds found in mate on the lipid metabolism of male Wistar rats fed with a high-fat diet. For this propose, it was obtained and optimized an extract of mate leaves (YME) by a Box-Behnken design, obtaining maximum yields of 357, 41 and 15 mg/g dry material, respectively. Subsequently, the main compounds were separated by solid phase extraction and fractionation using a polymer resin, methanol and water, in decreasing gradient polarity, achieving an enriched fraction of polyphenol and methylxanthines (MXPL) and an enriched fraction of saponins (SFL). Yields for polyphenols, saponins and methylxanthines were 497, 88 and 245 mg/g of dry material, respectively. Twenty four male Wistar rats were submitted to a high-fat diet and six to a standard diet, during five weeks and separated in five groups (standard diet (control) (n = 6); high-fat diet (n = 6); YME-treated group (n = 6); MXPL-treated group (n = 6); SFL-treated group (n = 6). No significant increase in rats body weight fed with high-fat diet was observed. However, there were evident alterations in fat other relevant parameters related to metabolism. Dissimilar results regarding the reduction of body weight, plasma levels of glucose and lipogenesis, for instance, are opposed to other studies, previously reported in the literature, suggesting that the animal model might be determinant in the evaluation of these activities. Likewise, effects observed in the crude extract and enriched fractions clearly indicate that these may be different, even opposite, leading to believe that the main compounds of mate have different effects on metabolism when are tested separately.
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Application of Infrared Spectroscopy and Chemometrics to the Cocoa Industry for Fast Composition Analysis and Fraud DetectionQuelal Vásconez, Maribel Alexandra 20 January 2020 (has links)
[ES] El cacao es un producto de alto valor, no únicamente por sus características sensoriales, sino porque también presenta un alto contenido en antioxidantes y alcaloides estimulantes con efectos saludables. Debido a la alta demanda, la industria del cacao en polvo tiene el desafío de asegurar la calidad de grandes volúmenes de producción de una manera rápida y precisa, evitando la presencia de contaminantes o adulterantes en la materia prima, ofreciendo productos donde se preserven las propiedades saludables. La espectroscopia del infrarrojo cercano (NIR) es una tecnología rápida y no destructiva útil en el análisis de productos alimentarios. La presente tesis doctoral se centra en evaluar el potencial uso del NIR como una herramienta de control de calidad con el fin de poder resolver problemas que se presentan en la industria del cacao en polvo. Los problemas a resolver incluyen la detección de materiales no deseados o adulterantes en el cacao en polvo, y la monitorización rápida y precisa del contenido de flavanoles y metilxantinas del cacao en polvo durante el proceso de alcalinización. El primer capítulo evalúa la viabilidad del NIR, en combinación con análisis quimiométricos, en la detección de la presencia de materiales no deseados o adulterantes como son cascarilla de cacao o harina de algarroba. Para ello, diferentes muestras de cacao en polvo natural y con diferentes niveles de alcalinización (suave, medio y fuerte) fueron mezcladas con distintas proporciones de cascarilla de cacao (con cacao natural) o harina de algarroba (con cacao natural y alcalinizado). Los resultados obtenidos indican que el NIR, combinado con modelos estadísticos tales como el análisis discriminante por mínimos cuadrados parciales (PLS-DA) y la regresión parcial de mínimos cuadrados (PLS), es un método rápido y eficaz para identificar cualitativa y cuantitativamente materiales no deseados o adulterantes como la cascarilla y la algarroba en cacao en polvo, independientemente del grado de alcalinización o el nivel de tostado de la harina de algarroba.
En el segundo capítulo, el análisis composicional del cacao en polvo se orientó al control de los cambios producidos en el contenido de flavanoles y metilxantinas debidos al proceso de alcalinización al que se somete el caco en polvo. Se determinó el contenido de catequina, epicatequina, cafeína y teobromina mediante cromatografía líquida de alta resolución (HPLC), correlacionándose los contenidos obtenidos para cada uno de estos compuestos con las determinaciones NIR. Se obtuvieron buenos modelos para la predicción de los compuestos mediante regresión PLS con valores superiores a 3 para la relación entre el rendimiento y la desviación (RDP), lo cual demuestra que los modelos obtenidos pueden ser utilizados para la rápida y fiable predicción del contenido de flavanoles y metilxantinas en cacaos naturales y con diferentes niveles de alcalinización. / [CAT] El cacau és un producte d'alt valor, no sols per les seues característiques sensorials, sinó perquè també presenta un elevat contingut en antioxidants i alcaloids estimulants amb efectes saludables. A conseqüència a l'alta demanda, l'industria del cacau en pols té el desafiament d'assegurar la qualitat de grans volums de producció d'una manera ràpida i precisa, evitant la presència de contaminants o adulterants en la matèria cosina, oferint productes a on se preserven les propietats saludables. L'espectroscòpia de l'infrarroig proper (NIR) és una tecnologia ràpida i no destructiva útil en l'anàlisi de productes alimentaris. La present tesis doctoral se centra en avaluar el potencial ús del NIR com una eina de control de qualitat amb l'objectiu de poder resoldre problemes que es presenten en l'industria del cacau en pols. Els problemes a resoldre inclouen la detecció de materials no desitjats o adulterants en el cacau en pols, i la monitorització ràpida i precisa del contingut de flavanols i metilxantines del cacau en pols durant el procés d'alcalinització. El primer capítol avalua la viabilitat del NIR, en combinació amb anàlisis quimiométrics, en la detecció de la presència de materials no desitjats o adulterants com són pellofa de cacau o farina de garrofa. Per a això, diferents mostres de cacau en pols natural i amb diferents nivells d'alcalinització (suau, mig i fort) foren barrejades en distintes proporcions de pellofa de cacau (en cacau natural) o farina de garrofa (en cacau natural i alcalinisat).
Els resultats obtinguts per a NIR, combinats amb models estadístics com l'anàlisi discriminant per mínims quadrats parcials (PLS-DA) i la regressió parcial de mínims quadrats (PLS), és un mètode ràpid i eficaç per identificar materials no desitjats o adulterants com la pellofa de cacau o la farina de garrofa, amb independència del grau d'alcalinització del cacau o de torrat de la farina de garrofa.
En el segon capítol, l'anàlisi composicional del cacau en pols s'orientà al control dels canvis produïts en el contingut de flavanols i metilxantines a causa del procés d'alcalinització al que se sotmet el cacau en pols. Es va determinar el contingut de catequina, epicatequina, cafeïna i teobromina mitjançant cromatografia líquida d'alta resolució (HPLC), i es van correlacionar els continguts obtinguts per a cadascun d'estos composts amb les determinacions NIR. Es van obtindré bons models per a la predicció dels composts mitjançant regressió PLS amb valors superiors a 3 per a la relació entre el rendiment i la desviació (RDP), la qual cosa demostra que els models obtinguts poden ser emprats per a la ràpida i fiable predicció del contingut de flavanols i metilxantines en cacaus naturals o amb diferents nivells d'alcalinització. / [EN] Cocoa is a product of high value, not only because of its sensory characteristics, but also because it has a high content of antioxidants and stimulating alkaloids with health effects. Due to the high demand, the cocoa powder industry has the challenge of ensuring the quality of large volumes of production in a fast and accurate way, avoiding the presence of contaminants or adulterants in the raw material, offering products where the healthy properties are preserved. The near infrared spectroscopy (NIR) is a rapid and non-destructive technology useful in the analysis of food products. The present doctoral thesis focuses on evaluating the potential use of NIR as a quality control tool in order to solve problems that arise in the cocoa industry powdered. The problems to solve include the detection of unwanted materials or adulterants in the cocoa powder, and the rapid and accurate monitorization of the flavanols and methylxanthines content in the cocoa powder during the alkalization process. The first chapter evaluates the viability of the NIR, in combination with chemometric analysis, in the detection of presence of unwanted materials or adulterants such as cocoa shell or carob flour. For this, different samples of natural cocoa powder and with different levels of alkalization (light, medium and strong) were mixed with different proportions of cocoa shell (with natural cocoa) or carob flour (with natural and alkalized cocoa).
The results obtained indicate that the NIR combined with statistical models such as the partial least squares discriminant analysis (PLS-DA) and the partial least squares regression (PLS), is a fast and efficient method to identify qualitative and quantitative unwanted materials or adulterants such as shell and carob in cocoa powder, regardless of the degree of alkalization or level of roasting of carob flour.
In the second chapter, the compositional analysis of cocoa powder was oriented to the control of the changes produced in the content of flavanols and methylxanthines due to the process of alkalization to which the cocoa powder is subjected. The content of catechin, epicatechin, caffeine and theobromine were determined by high performance liquid chromatography (HPLC), correlating the contents obtained for each of these compounds with the NIR determinations. Good models were obtained for the prediction of compounds by regression PLS with values above 3 for the ratio of performance to deviation (RDP), which shows that the obtained models can be used for the quick and reliable prediction of flavanol content and methylxanthines in natural cocoas and with different alkalization levels. / This Doctoral Thesis has been carried out
thanks to a doctoral studies scholarship granted
by the Ministry of Higher Education, Science,
Technology and Innovation (SENESCYT) of
the Republic of Ecuador / Quelal Vásconez, MA. (2019). Application of Infrared Spectroscopy and Chemometrics to the Cocoa Industry for Fast Composition Analysis and Fraud Detection [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/135258 / TESIS
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Central Nervous System Stimulants and Drugs That Suppress AppetiteBello, Nicholas T., Zahner, Matthew R. 01 January 2017 (has links)
The Side Effects of Drugs Annuals forms a series of volumes in which the adverse effects of drugs and adverse reactions to them are surveyed. The series supplements the contents of Meyler's Side Effects of Drugs: The International Encyclopedia of Adverse Drug Reactions and Interactions. The purpose of this supplement is to provide a concise reference of the newly available literature to support the existing information regarding the known adverse effects of commonly prescribed medications or abused drugs. The information covers peer-reviewed publications from January 2016 to December 2016. This review focused on CNS stimulants and drugs that suppress appetite. It covers amphetamines (including lisdexamfetamine, methamphetamine and 3,4-methylenedioxymetamphetamine), methylphenidate, atomoxetine, modafinil and armodafinil, methylxanthines (caffeine), monotherapies and combinational therapies that suppress appetite (lorcaserin, phentermine, phentermine/topiramate) and medications used in Alzheimer's disease and cognitive decline (rivastigmine, donepezil and memantine).
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Valorisation of Compounds with High Nutritional Value from Cocoa By-Products as Food Ingredients and AdditivesRojo Poveda, Olga 17 May 2021 (has links) (PDF)
This doctoral thesis was conducted in the framework of a co-supervised PhD between the Department of Agriculture, Forestry and Food Sciences of the University of Turin and the Unit of Pharmacognosy, Bioanalysis and Drug Discovery of the Faculty of Pharmacy at the Université libre de Bruxelles. The present manuscript was conceived as a thesis of articles and is composed of 9 different scientific publications. The general introduction of the work was issued from a published narrative review, while the result and discussion part is composed by eight chapters based on different scientific articles issued from the PhD project. The cocoa bean shell (CBS) is the external tegument that covers the cocoa bean, and is one of the major by-products in cocoa industry. It is normally discarded or underutilized, which could result in economical and environmental issues. However, CBS represents a notable source of polyphenols and methylxanthines (theobromine and caffeine) which can give it different biofunctionalities such as antioxidant and antidiabetic properties, among others. It also contains high amounts of dietary fiber (about 50% w/w), minerals, vitamins, and proteins. CBS has low-fat content, and interesting cocoa-aroma compounds. All this could make CBS useful as a food ingredient, and source of biofunctional compounds. The first part of the experimental work of this thesis is devoted to the chemical characterization of CBS and the establishment of its polyphenolic and volatile organic compound (aroma) profiles. The utilization of such profiles, determined by both complete characterization methods and screening methods, was also proposed for authentication purposes of CBS depending on its geographical origin and variety. In a second step, the utilization of CBS as a low-cost food ingredient for functional food production was envisaged. CBS-based beverages and biscuits were proposed as model foods. The influence of the CBS addition to the model foods was evaluated from both technological and nutritional points of view. Changes on the physicochemical characteristics of the model foods were assessed as well as their content in compounds of interest and potential biofunctionalities. Moreover, these studies served also to evaluate the effect of the different food matrices on the bioaccessibility and intestinal permeability of the bioactive compounds contained in CBS. In the third and last part of this work, a different utility was given to the study of the cocoa by-product. The antimicrobial potential of CBS was assessed against different bacterial and fungal strains and a metabolomic strategy was applied in order to individualize the putative active compounds against the Streptococcus mutans proliferation. This work was a contribution for the valorization of a high add-value product such as the CBS, and a step towards a zero-waste cocoa industry within the frame of sustainable circular economy. / Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie) / info:eu-repo/semantics/nonPublished
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