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Síntese e avaliação de derivados furânicos, tetraidrofurânicos e pirrólicos com potencial atividade tripanocida / Synthesis and evaluation of furan, tetrahydrofuran and pyrrole derivatives with potential trypanocidal activityAna Paula Hartmann 13 July 2015 (has links)
A Doença de Chagas é causada pelo Trypanosoma cruzi, e possui duas fases clínicas, sendo o tratamento com o fármaco benznidazol eficaz somente na fase aguda, porém com diversos efeitos adversos ao longo do período do tratamento. Desta forma, consórcios vêm sendo estabelecidos entre \"governo - universidade - indústria\", com auxilio de capital nacional e estrangeiro para o desenvolvimento de novos fármacos. Apesar de diversas ferramentas disponíveis para o planejamento de novos compostos, a busca por produtos naturais ainda desperta interesse de muitos pesquisadores. Diversos trabalhos vêm descrevendo estudos de síntese e atividade tripanocida de lignanas, as quais merecem destaque, veraguensina (17) e grandisina (18). Devido à falta de tratamento e a alta toxicidade dos agentes disponíveis, este trabalho tem como objetivo sintetizar análogos dessas lignanas, relacionados a derivados de tetraidrofurânicos, furânicos, pirrólicos e de seus intermediários e testa-lasfrente à atividade tripanocida e citotóxica. O planejamento sintético envolveu a geração de derivados 1,4-diaril-2-butino-1,4-diol (28a-t) a partir da reação de condensação entre fenil carbinol (26) e aldeídos arílicos (27a-t) com diferentes padrões de substituiçõescom diversos grupos funcionais. Estes intermediários, obtidos em rendimentos moderados, foram convertidos aos correspondentes 1,4-diaril-1,4-diidroxílicos (30a-g), pela reação de redução em dióxido de platina e, posteriormente, oxidados a 1,4-diaril-1,4-dicetonas (29a-g). A partir da formação dos intermediários 29 e 30, os produtos de interesse, 2,5-diaril-furano (32a-g) e 2,5-diaril-tetraidrofurano (31a-g) foram preparados empregando reações de ciclização na presença de ácidos tríflico e trifluoroacético, respectivamente. Os intermediários e produtos obtidos em rendimentos de moderado a bom, totalizando 48 compostos, foram avaliados em ensaios de atividade tripanocida, envolvendo a cepa Tulahuen de T. cruzi, bem como ensaios de citotoxicidade. Considerando as cinco séries sintetizadas (28, 29, 30, 31 e 32), vale destacar que a maioria apresentou compostos com potente atividade tripanocida, a partir de 1,4 ?M, superior ao fármaco disponível benznidazol (7,9 ?M) e, adicionalmente, não apresentaram citotoxicidade em ensaios realizados por citometria de fluxo. / Chagas\' disease is caused by the Trypanosoma cruzi, whichhas two clinical stages. The treatment with the benznidazole is effective only in the acute stage, although with several side effects throughout the treatment period. Therefore, consortia are being established between \"government - university - industry\", with national and foreign financial support for drug discovery development. In spite of many available tools to design new compounds, the search for natural products still arouse interestfor a great number of researchers. Several papers have described studies of synthesis and trypanocidal activity of lignans, being veraguensin (17) and grandisin (18) worth to mention. Due to the lack of treatment and the high toxicity of the available drugs, this research has the aimto synthesize analogues from the above lignans, such astetrahydrofuran, furanic, pyrrolic derivatives and their intermediates,and test their trypanocidal activity and cytotoxicities. The synthetic strategy was based on the synthesis of 1,4-diarylacetylene-1,4-glycols (28a-t) via condensation reaction between phenyl carbinol (26) and substituted aryl aldehydes (27a-t) with several functional groups at different positionsof the aromatic ring. These intermediates, obtained in moderate yields, were converted to their corresponding 1,4-diaryl-1,4-dihydroxyl derivatives (30a-g) by the reduction reaction using platinum dioxide and, subsequently, oxidized to 1,4-diaryl-1,4-diketones (29a-g). From the synthesis of the intermediates 29 and 30, products of interest, 2,5-diaryl-furan (32a-g) and 2,5-diaryl-tetrahydrofuran (31a-g) were prepared from the cyclization reaction in the presence of the triflic and trifluoracetic acids, respectively. The intermediates and products, obtained in moderate to good yields, in a total of 48 compounds, were assessed in trypanocidal assays, using T. cruzi Tulahuen strain,as well as cytotoxicity assays. Considering the five synthesized series (28, 29, 30, 31 e 32), it is worth noting that the majority of the compounds showed potent trypanocidal activity from 1.4 ?M, higher than the available benznidazole (7,9 ?M) and, additionally, they were not cytotoxicin Flow Cytometry assays.
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Variabilidade de fenilpropanóides, lignanas tetraidrofurânicas e aristolactamas em Piper solmsianum C.DC. / Variability of phenylpropanoids, tetrahydrofuran lignans and aristolactams of Piper solmsianum C. DC.Navarro, Lucas Bergamo 05 March 2009 (has links)
Foi realizada uma investigação fitoquímica envolvendo diversos órgãos de plantas adultas (raízes, caules, folhas, inflorescências e sementes), plântulas (cultivadas in vivo e in vitro) e suspensões celulares de P. solmsianum. Dos órgãos estudados de plantas adultas, as raízes apresentaram a maior complexidade e diversidade química da planta, abrangendo ácidos benzóicos e benzaldeídos substituídos, esteróides, fenilpropanóides, lignanas tetraidrofurânicas e aristolactamas, enquanto que os outros órgãos acumulam principalmente fenilpropanóides e lignanas tetraidrofurânicas. As raízes de plântulas apresentaram semelhança qualitativa de metabólitos secundários quando comparadas às raízes de plantas adultas. No entanto, as partes aéreas apresentaram diferentes compostos como farnesol, fitol e α-tocoferol. Os extratos de plântulas separadas por tamanho foram comparados em relação à diversidade dos metabólitos encontrados, não sendo observada uma variação qualitativa muito significativa. Os extratos obtidos das células de suspensões celulares de P. solmsianum indicaram prevalência de ácidos graxos e esteróides, enquanto que o extrato obtido do meio de cultura apresentou como componente majoritário o ácido salicílico. / The phytochemical investigation was carried out to describe the composition in organs of adult plants (roots, steams, leaves, inflorescences and seeds), plantlets (in vivo and in vitro) and cell suspensions of Piper solmsianum. The roots of adult plants presented highest chemical diversity including benzoic acids, benzaldehydes, sterols, phenylpropanoids, tetrahydrofuran lignans and aristolactams, whereas aerial organs accumulate mainly phenylpropanoids and tetrahydrofuran lignans. The roots from plantlets presented qualitative similarity of secondary metabolites when compared to the roots of adult plants. However, the aerial parts from plantlets presented different composition including farnesol, phytol and α-tocopherol in addition to phenylpropanoids, but the plantlets at different developmental stages showed no significant qualitative variation. The extracts of cell suspensions of P. solmsianum indicated a suppressed phenylpropanoid metabolism with fatty acids and sterols in the cells and salicylic acid as major excreted compound in the culture medium.
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Metabolismo secundário e ligninas de espécies de Piper / Secondary metabolites and lignins from Piper speciesSilva, Adalberto Manoel da 05 September 2008 (has links)
O estudo químico das folhas e dos frutos de P. richardiaefolium resultou no isolamento de oito lignanas, sendo duas lignanas furofurânicas (sesamina e kobusina), quatro lignanas dibenzilbutirolactônicas (hinokinina, kusunokinina, arctigenina e haplomirfolina), duas lignanas dibenzilbutirolactólicas (cubebina e 3,4- dimetoxi-3,4-desmetilenodioxicubebina), dois cinamatos de bornila (ferulato de bornila e cumarato de bornila) e na identificação de duas amidas (piplartina e diidropiplartina). Das folhas de P. richardiaefolium foi extraído e analisado o óleo volátil. As estruturas das substâncias isoladas foram identificadas através de métodos espectroscópicos (RMN de 1H e de 13C e espectrometria de massas). O estudo de análise de componentes principais (PCA) das espécies Piper (P. truncatum - k 616, P. richardiaefolium - k 290, P. richardiaefolium - k 350, P. richardiaefolium - k 593, P. truncatum - k 597, P. pseudopotifolium - k 598, P. richardiaefolium - k 854, P. richardiaefolium - k 610, P. truncatum - k 112, P. pseudopotifolium - k 211 e P. cernuum - k 137) permitiu agrupar as espécies em dois grandes grupos e quatro subgrupos em relação à similaridade entre elas. Ligninas do caule de seis espécies de Piper foram extraídas utilizando o método de degradação de Klason e método de Bjorkman, e analisadas por métodos espectroscópicos (IV, RMN de 1H e de 13C). O método de degradação por oxidação por nitrobenzeno foi o escolhido para determinar a relação entre os monolignóis siringila e guaiacila. Os principais metabólitos das espécies estudadas foram comparados com os tipos de ligninas das mesmas espécies e os resultados sugeriram uma independência entre as vias biossintéticas de ligninas e lignanas. / The chemical study of leaves and the fruits of P. richardiaefolium resulted in the isolation of eight lignans, being two furofurânics lignans (sesamin and kobusin), four dibenzylbutirolactonics lignans (hinokinin, kusunokinin, arctigenin and haplomirfolin), two dibenzylbutirolactolics lignans (cubebin and 3\',4\'-dimethoxy-3,4- desmethylenedioxicubebin), two cinnamates (bornyl ferulate and bornyl cumarate) and in the identification of two amides (piplartine and dihydropiplartine). Of leaves of P. richardiaefolium was extracted and analyzed the volatile oil. The structures of isolated substances had been identified using the spectroscopic methods (1H and 13C NMR) and mass spectrometry. The study of principal components analysis (PCA) of the species Piper (P. truncatum - k 616, P. richardiaefolium - k 290, P. richardiaefolium - k 350, P. richardiaefolium - k 593, P. truncatum - k 597, P. pseudopotifolium - k 598, P. richardiaefolium - k 854, P. richardiaefolium - k 610, P. truncatum - k 112, P. pseudopotifolium - k 211 and P. cernuum - k 137) allowed the separation in two groups and four sub-groups. Lignins of stem of six species of Piper had been extracted using the method of degradation of Klason and method of Bjorkman, and analyzed for spectroscopic methods (IR, 1H and 13C NMR). The degradation method by nitrobenzene oxidation was chosen to determine the relationship between monolignols syringil and guaiacyl moieties. The major metabolities of the Piper species were compared to the lignins types of the same species and the results suggested independence between the biosynthetic pathways of lignins and lignans.
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Linhaça e lignanas: efeito do consumo sobre indicadores nutricionais e inflamatórios / Flaxseed and lignans: effects of consumption on nutritional and inflammatory.Cassani, Roberta Soares Lara 25 September 2009 (has links)
O processo inflamatório subclinico encontra-se associado à prevenção e controle de um agrupamento de fatores de risco (FR) nutricionais, entre eles, dislipidemia e aumento de depósito de gordura visceral. Indicadores nutricionais, inflamatórios e metabólicos parecem estar associados com o estilo de vida. A semente de linhaça tem sido reconhecida como um alimento rico em fibras e -3, entretanto, um novo constituinte de sua composição nutricional tem merecido atenção, pelo seu papel antiinflamatório e antioxidante. Este componente é chamado de lignanas, um polímero complexo e o principal constituinte não-carbohidrato de plantas vasculares. Está ligado a fibras de celulose, e é responsável por reforçar a estrutura das paredes celulares, o que previne o colapso das mesmas. Lignanas, em contato com a microflora intestinal humana transformam-se em enterolignanas, especialmente, enterodiol e enterolactona. O presente trabalho tem por hipótese que o teor de lignanas dietético pode interferir no perfil metabólico, e alterar fatores de riscos envolvidos no estado nutricional, e consequentemente na saúde. O conhecimento de que diferentes características na composição nutricional de macronutrientes da dieta poderiam modificar o perfil inflamatório, independentemente, da presença das enterolignanas provenientes da semente de linhaça também constituíram o objetivo deste estudo. Por 42 dias, foram avaliados 52 funcionários, pertencentes ao sexo masculino, com idade média de 37± 9 anos, de uma indústria de grande porte, na cidade de Itu-SP. Os voluntários foram divididos em 4 grupos de pesquisa, sendo, um grupo controle, e três grupos com dietas isocalóricas e diferentes proporções no % de carboidratos (CH), e acréscimo de semente de linhaça em pó ou arroz cru triturados (protocolo duplo cego). Foi preenchida ficha de coleta de informações sobre dados pessoais e conhecimento de fatores de risco (hipertensão, dislipidemia e diabetes), comportamentos de risco (tabagismo e sedentarismo) e antecedentes familiares. Foi também realizada avaliação clinico - laboratorial, no qual se obteve o registro de medidas antropométricas, medida da pressão arterial e coleta de sangue venoso em jejum de 12 h para avaliação de indicadores bioquímicos referentes à FR cardiovascular, tais como, colesterol total e frações (LDL-c e HDL-c), triglicérides, glicemia, insulina, Homa-beta e Homa-IR, ácido úrico, bem como, para avaliação de indicadores inflamatórios (Proteína C Reativa (PCR), Fator de Necrose Tumoral (TNF-) e Isoprostane Sérico), hormonais (Leptina e Adiponectina) e nutricionais (Enterodiol e Enterolactona séricas e urinárias). Observou-se que para redução significativa das medidas antropométricas estudadas e indicador de estresse oxidativo não houve diferenças entre os grupos que receberam intervenção dietética. Entretanto, para a melhora do perfil bioquímico, inflamatório, hormonal e nutricional, diferentes respostas foram encontradas. Os grupos que receberam dietas com redução de CH total (32% e 35%) mostraram benefícios, no que se refere ao perfil bioquímico, especialmente, colesterol total, LDL-c e ácido úrico, como também, para o perfil hormonal, referente aos níveis de adiponectina (p <0,05). Com relação aos níveis de PCR e TNF-, apenas os grupos que tiveram acréscimo de semente de linhaça na dieta apresentaram redução significativa (p<0,05). Para os níveis de triglicérides, somente o grupo com adição de semente de linhaça e 32 % de CH total apresentou diminuição significativa (p<0,05). Foi observado que com 32 % de CH total ingerido e adição de um alimento rico em lignanas constituiu-se uma estratégia nutricional relevante, para prevenção primária de fatores de risco metabólicos e controle da inflamação subclinica, o que pode contribuir na redução da morbi-mortalidade a eles associada. / The control of subclinical inflammatory process is associated with the prevention nutritional RF (risk factor), such as dislipidemia and the increase of visceral fat deposition. Nutritional, inflammatory and metabolic indicators seem also to related to life style. The linseed has been recognized as rich in fibers and -3. However, a new component in its nutritional composition has deserved the attention for its anti- inflammatory and antioxidant roles. This component is called lignans, a complex polymer and the main non-carbohydrate constituent of vascular plants. It is binded to cellulose fibers and is responsible for reinforcing cell walls structure, preventing them from collapsing. Plant lignans, in contact with the human intestinal flora, become enterolignans, specially enterodiol and enterolactone. This present work hypothetically that the amount of dietetic plant lignans interfere in the metabolic profile, altering the risk factors involved in the nutritional health state and consequently, the welfare state. Therefore, the objective of this study is to know if different diet nutritional composition characteristics can change the inflammatory profile, independently of the presence of enterolignans from the linseed. For 42 days, 52 male volunteers, average 37±9 years old, from a industrial city of Itu-SP, were evaluated. The volunteers were divided into 4 research groups; one control group and 3 groups on isocaloric diets with different proportion of carbohydrate (CH) and the addition of powdered linseed or ground raw rice (a double blind protocol). Personal data, RF (hypertension, dislipidemia and diabetes), habits (smoking and sedentary) and family antecedents were collected. A nutritional-laboratorial evaluation was performed in order to get anthropometric data; blood pressure checked and blood samples (after 12 hours fast) for total cholesterol and fractions (LDL-c and HDL-c ), triglycerides, glycemia, insulin, Homa-beta and Homa-IR, uric acid, inflammatory indicators (Reactive-C Protein (PCR) , Tumoral Necrosis Factor (TNF-a) and Seric Isoprostane ), hormonal (Leptin and Adiponectin), enterodiol and enterolactone seric and urinary enterolignins. It was observed a reduction of the studied anthropometric measures and for the oxidative stress indicators. A significant change occurred in the anthropometric measurements and the oxidative stress marker evaluated for all groups, but no difference among them was noted. On the other hand, biochemical, inflammatory, hormonal and nutritional profile significant differences among groups was observed. The groups that received diets with the reduction of the total CH (32% and 35% ) showed improvements in the biochemical profile, specially in the total cholesterol, LDL-c and uric acid, as well as the hormonal profile, in the levels of adiponectin (p< 0,05) . The levels of PCR and TNF-a, only the groups that had the linseed, showed a reduction (p< 0,05). For the triglycerides levels, only the group with the addition of linseed and 32% of total CH showed a decrease. It was observed with 32% of CH and the addition of food lignans constitute a nutritional relevant strategy for the primary prevention of metabolic risk factors and control of subclinical inflammation, contributing to the reduction of the associated morbi-mortality.
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Pressurized low polarity water extraction of lignans, proteins and carbohydrates from flaxseed mealHo, Colin Hao Lim 08 January 2007 (has links)
The physiological benefits of flaxseed against pathological disturbances, such as cancers and heart diseases, are mainly attributed to its high lignan content. This study (Experiment 1) examined the application of pressurized low polarity water (PLPW) for extraction of lignans, proteins and carbohydrates from defatted flaxseed meal. Key processing conditions included temperature (130, 160, 190°C), solvent pH (4, 6.5 and 9), solvent to solid ratio (S/S) (90, 150 and 210 mL/g) and introduction of co-packing material (0 and 3 g glass beads). The addition of 3 g glass beads as co-packing material facilitated extraction by enhancing surface contact between the liquid and solid thus shortening extraction time. Elevated temperature accelerated the extraction rate by increasing the solid diffusion coefficient thereby reducing the extraction time. The maximum yield of lignans (99 %) was obtained at temperatures ranging from 160°C to 190°C, with solvent volume of 180 mL (90 mL/g meal) at pH 9. Optimal conditions for protein extraction (70 %) were pH 9, extraction volume of 420 mL (210 mL/g meal) and 160°C. Total carbohydrates yield was maximized at 50% recovery at pH 4 and 160°C with 420 mL solvent (210 mL/g meal). Increased temperature accelerated extraction, thus reducing solvent volume and time to reach equilibrium. For the extraction of proteins, however, a temperature of 130-160°C is recommended, as proteins are vulnerable to thermal degradation due to heat decomposition.
The effects of flow rate and geometric dimensions for extraction of lignans and other flaxseed meal bioactives were further investigated in Experiment 2, based on the variables optimized in the previous experiment. Defatted flaxseed meal was extracted with pH 9 buffered water with meal to co-packing glass beads ratio of 1:1.5 at 5.2 MPa (750 psi) and 180°C. The aqueous extracts were analyzed for lignan, protein and carbohydrate using HPLC and colorimetric methods. The optimal extraction yields for lignan, protein and carbohydrate were found at flow rates of 1 to 2 mL/min with bed depth between 20 and 26 cm and a S/S ratio of 40 to 100 mL/g. The combination of low flow rate and high bed depth allowed the use of lower S/S ratio with reduced total solvent volume consumption.
This study also evaluated the mass transfer kinetics governing the process of lignan extraction from flaxseed meal in a fixed bed extraction cell. Diffusion of solute into the continuously flowing solvent was mainly responsible for the mass transfer mechanism as flow rate did not increase proportionally with the yield and rate of extraction. The extraction kinetics were studied on the basis of two approaches: Fick’s diffusion equation and a two-site exponential kinetic model. The proposed two-site exponential kinetic model corresponding to the two-stage extraction (rapid and slow phases) successfully described the experimental data. Diffusivities attained from Fick’s diffusion model ranged from 2 x 10-13 to 9 x 10-13 m2s-1 while mass transfer coefficients were between 4.5 x 10-8 and 2.3 x 10-7 ms-1 for extraction of lignans at 180°C, pH 9 with 1:1.5 meal to co-packing material ratio. / February 2007
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Pressurized low polarity water extraction of lignans, proteins and carbohydrates from flaxseed mealHo, Colin Hao Lim 08 January 2007 (has links)
The physiological benefits of flaxseed against pathological disturbances, such as cancers and heart diseases, are mainly attributed to its high lignan content. This study (Experiment 1) examined the application of pressurized low polarity water (PLPW) for extraction of lignans, proteins and carbohydrates from defatted flaxseed meal. Key processing conditions included temperature (130, 160, 190°C), solvent pH (4, 6.5 and 9), solvent to solid ratio (S/S) (90, 150 and 210 mL/g) and introduction of co-packing material (0 and 3 g glass beads). The addition of 3 g glass beads as co-packing material facilitated extraction by enhancing surface contact between the liquid and solid thus shortening extraction time. Elevated temperature accelerated the extraction rate by increasing the solid diffusion coefficient thereby reducing the extraction time. The maximum yield of lignans (99 %) was obtained at temperatures ranging from 160°C to 190°C, with solvent volume of 180 mL (90 mL/g meal) at pH 9. Optimal conditions for protein extraction (70 %) were pH 9, extraction volume of 420 mL (210 mL/g meal) and 160°C. Total carbohydrates yield was maximized at 50% recovery at pH 4 and 160°C with 420 mL solvent (210 mL/g meal). Increased temperature accelerated extraction, thus reducing solvent volume and time to reach equilibrium. For the extraction of proteins, however, a temperature of 130-160°C is recommended, as proteins are vulnerable to thermal degradation due to heat decomposition.
The effects of flow rate and geometric dimensions for extraction of lignans and other flaxseed meal bioactives were further investigated in Experiment 2, based on the variables optimized in the previous experiment. Defatted flaxseed meal was extracted with pH 9 buffered water with meal to co-packing glass beads ratio of 1:1.5 at 5.2 MPa (750 psi) and 180°C. The aqueous extracts were analyzed for lignan, protein and carbohydrate using HPLC and colorimetric methods. The optimal extraction yields for lignan, protein and carbohydrate were found at flow rates of 1 to 2 mL/min with bed depth between 20 and 26 cm and a S/S ratio of 40 to 100 mL/g. The combination of low flow rate and high bed depth allowed the use of lower S/S ratio with reduced total solvent volume consumption.
This study also evaluated the mass transfer kinetics governing the process of lignan extraction from flaxseed meal in a fixed bed extraction cell. Diffusion of solute into the continuously flowing solvent was mainly responsible for the mass transfer mechanism as flow rate did not increase proportionally with the yield and rate of extraction. The extraction kinetics were studied on the basis of two approaches: Fick’s diffusion equation and a two-site exponential kinetic model. The proposed two-site exponential kinetic model corresponding to the two-stage extraction (rapid and slow phases) successfully described the experimental data. Diffusivities attained from Fick’s diffusion model ranged from 2 x 10-13 to 9 x 10-13 m2s-1 while mass transfer coefficients were between 4.5 x 10-8 and 2.3 x 10-7 ms-1 for extraction of lignans at 180°C, pH 9 with 1:1.5 meal to co-packing material ratio.
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Pressurized low polarity water extraction of lignans, proteins and carbohydrates from flaxseed mealHo, Colin Hao Lim 08 January 2007 (has links)
The physiological benefits of flaxseed against pathological disturbances, such as cancers and heart diseases, are mainly attributed to its high lignan content. This study (Experiment 1) examined the application of pressurized low polarity water (PLPW) for extraction of lignans, proteins and carbohydrates from defatted flaxseed meal. Key processing conditions included temperature (130, 160, 190°C), solvent pH (4, 6.5 and 9), solvent to solid ratio (S/S) (90, 150 and 210 mL/g) and introduction of co-packing material (0 and 3 g glass beads). The addition of 3 g glass beads as co-packing material facilitated extraction by enhancing surface contact between the liquid and solid thus shortening extraction time. Elevated temperature accelerated the extraction rate by increasing the solid diffusion coefficient thereby reducing the extraction time. The maximum yield of lignans (99 %) was obtained at temperatures ranging from 160°C to 190°C, with solvent volume of 180 mL (90 mL/g meal) at pH 9. Optimal conditions for protein extraction (70 %) were pH 9, extraction volume of 420 mL (210 mL/g meal) and 160°C. Total carbohydrates yield was maximized at 50% recovery at pH 4 and 160°C with 420 mL solvent (210 mL/g meal). Increased temperature accelerated extraction, thus reducing solvent volume and time to reach equilibrium. For the extraction of proteins, however, a temperature of 130-160°C is recommended, as proteins are vulnerable to thermal degradation due to heat decomposition.
The effects of flow rate and geometric dimensions for extraction of lignans and other flaxseed meal bioactives were further investigated in Experiment 2, based on the variables optimized in the previous experiment. Defatted flaxseed meal was extracted with pH 9 buffered water with meal to co-packing glass beads ratio of 1:1.5 at 5.2 MPa (750 psi) and 180°C. The aqueous extracts were analyzed for lignan, protein and carbohydrate using HPLC and colorimetric methods. The optimal extraction yields for lignan, protein and carbohydrate were found at flow rates of 1 to 2 mL/min with bed depth between 20 and 26 cm and a S/S ratio of 40 to 100 mL/g. The combination of low flow rate and high bed depth allowed the use of lower S/S ratio with reduced total solvent volume consumption.
This study also evaluated the mass transfer kinetics governing the process of lignan extraction from flaxseed meal in a fixed bed extraction cell. Diffusion of solute into the continuously flowing solvent was mainly responsible for the mass transfer mechanism as flow rate did not increase proportionally with the yield and rate of extraction. The extraction kinetics were studied on the basis of two approaches: Fick’s diffusion equation and a two-site exponential kinetic model. The proposed two-site exponential kinetic model corresponding to the two-stage extraction (rapid and slow phases) successfully described the experimental data. Diffusivities attained from Fick’s diffusion model ranged from 2 x 10-13 to 9 x 10-13 m2s-1 while mass transfer coefficients were between 4.5 x 10-8 and 2.3 x 10-7 ms-1 for extraction of lignans at 180°C, pH 9 with 1:1.5 meal to co-packing material ratio.
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Phytoestrogens and prostate cancer : experimental, clinical, and epidemiological studies /Bylund, Annika, January 2007 (has links)
Diss. (sammanfattning) Umeå : Univ., 2007. / Härtill 5 uppsatser.
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Metabolismo secundário e ligninas de espécies de Piper / Secondary metabolites and lignins from Piper speciesAdalberto Manoel da Silva 05 September 2008 (has links)
O estudo químico das folhas e dos frutos de P. richardiaefolium resultou no isolamento de oito lignanas, sendo duas lignanas furofurânicas (sesamina e kobusina), quatro lignanas dibenzilbutirolactônicas (hinokinina, kusunokinina, arctigenina e haplomirfolina), duas lignanas dibenzilbutirolactólicas (cubebina e 3,4- dimetoxi-3,4-desmetilenodioxicubebina), dois cinamatos de bornila (ferulato de bornila e cumarato de bornila) e na identificação de duas amidas (piplartina e diidropiplartina). Das folhas de P. richardiaefolium foi extraído e analisado o óleo volátil. As estruturas das substâncias isoladas foram identificadas através de métodos espectroscópicos (RMN de 1H e de 13C e espectrometria de massas). O estudo de análise de componentes principais (PCA) das espécies Piper (P. truncatum - k 616, P. richardiaefolium - k 290, P. richardiaefolium - k 350, P. richardiaefolium - k 593, P. truncatum - k 597, P. pseudopotifolium - k 598, P. richardiaefolium - k 854, P. richardiaefolium - k 610, P. truncatum - k 112, P. pseudopotifolium - k 211 e P. cernuum - k 137) permitiu agrupar as espécies em dois grandes grupos e quatro subgrupos em relação à similaridade entre elas. Ligninas do caule de seis espécies de Piper foram extraídas utilizando o método de degradação de Klason e método de Bjorkman, e analisadas por métodos espectroscópicos (IV, RMN de 1H e de 13C). O método de degradação por oxidação por nitrobenzeno foi o escolhido para determinar a relação entre os monolignóis siringila e guaiacila. Os principais metabólitos das espécies estudadas foram comparados com os tipos de ligninas das mesmas espécies e os resultados sugeriram uma independência entre as vias biossintéticas de ligninas e lignanas. / The chemical study of leaves and the fruits of P. richardiaefolium resulted in the isolation of eight lignans, being two furofurânics lignans (sesamin and kobusin), four dibenzylbutirolactonics lignans (hinokinin, kusunokinin, arctigenin and haplomirfolin), two dibenzylbutirolactolics lignans (cubebin and 3\',4\'-dimethoxy-3,4- desmethylenedioxicubebin), two cinnamates (bornyl ferulate and bornyl cumarate) and in the identification of two amides (piplartine and dihydropiplartine). Of leaves of P. richardiaefolium was extracted and analyzed the volatile oil. The structures of isolated substances had been identified using the spectroscopic methods (1H and 13C NMR) and mass spectrometry. The study of principal components analysis (PCA) of the species Piper (P. truncatum - k 616, P. richardiaefolium - k 290, P. richardiaefolium - k 350, P. richardiaefolium - k 593, P. truncatum - k 597, P. pseudopotifolium - k 598, P. richardiaefolium - k 854, P. richardiaefolium - k 610, P. truncatum - k 112, P. pseudopotifolium - k 211 and P. cernuum - k 137) allowed the separation in two groups and four sub-groups. Lignins of stem of six species of Piper had been extracted using the method of degradation of Klason and method of Bjorkman, and analyzed for spectroscopic methods (IR, 1H and 13C NMR). The degradation method by nitrobenzene oxidation was chosen to determine the relationship between monolignols syringil and guaiacyl moieties. The major metabolities of the Piper species were compared to the lignins types of the same species and the results suggested independence between the biosynthetic pathways of lignins and lignans.
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Variabilidade de fenilpropanóides, lignanas tetraidrofurânicas e aristolactamas em Piper solmsianum C.DC. / Variability of phenylpropanoids, tetrahydrofuran lignans and aristolactams of Piper solmsianum C. DC.Lucas Bergamo Navarro 05 March 2009 (has links)
Foi realizada uma investigação fitoquímica envolvendo diversos órgãos de plantas adultas (raízes, caules, folhas, inflorescências e sementes), plântulas (cultivadas in vivo e in vitro) e suspensões celulares de P. solmsianum. Dos órgãos estudados de plantas adultas, as raízes apresentaram a maior complexidade e diversidade química da planta, abrangendo ácidos benzóicos e benzaldeídos substituídos, esteróides, fenilpropanóides, lignanas tetraidrofurânicas e aristolactamas, enquanto que os outros órgãos acumulam principalmente fenilpropanóides e lignanas tetraidrofurânicas. As raízes de plântulas apresentaram semelhança qualitativa de metabólitos secundários quando comparadas às raízes de plantas adultas. No entanto, as partes aéreas apresentaram diferentes compostos como farnesol, fitol e α-tocoferol. Os extratos de plântulas separadas por tamanho foram comparados em relação à diversidade dos metabólitos encontrados, não sendo observada uma variação qualitativa muito significativa. Os extratos obtidos das células de suspensões celulares de P. solmsianum indicaram prevalência de ácidos graxos e esteróides, enquanto que o extrato obtido do meio de cultura apresentou como componente majoritário o ácido salicílico. / The phytochemical investigation was carried out to describe the composition in organs of adult plants (roots, steams, leaves, inflorescences and seeds), plantlets (in vivo and in vitro) and cell suspensions of Piper solmsianum. The roots of adult plants presented highest chemical diversity including benzoic acids, benzaldehydes, sterols, phenylpropanoids, tetrahydrofuran lignans and aristolactams, whereas aerial organs accumulate mainly phenylpropanoids and tetrahydrofuran lignans. The roots from plantlets presented qualitative similarity of secondary metabolites when compared to the roots of adult plants. However, the aerial parts from plantlets presented different composition including farnesol, phytol and α-tocopherol in addition to phenylpropanoids, but the plantlets at different developmental stages showed no significant qualitative variation. The extracts of cell suspensions of P. solmsianum indicated a suppressed phenylpropanoid metabolism with fatty acids and sterols in the cells and salicylic acid as major excreted compound in the culture medium.
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