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"Efeito da modificação ácido-metanólica nas características estruturais e fisico-químicas de amidos de milho e mandioca" /Ferrini, Luara Mirela Kurachi. January 2006 (has links)
Orientador: Célia Maria Landi Franco / Banca: Cláudio Ernani Mendes da Silva / Banca: Maurício Boscolo / Resumo: XIII Modificações de amidos têm como objetivo melhorar suas características tecnológicas e estender sua utilização industrial e comercial. Amidos modificados por ácido podem ser usados na produção de confeitos, como substitutos de gordura e na indústria farmacêutica. O rendimento do amido ácido-modificado diminui quanto maior a concentração de ácido e tempo de reação. Maiores conversões de amido com menor produção de dextrinas de baixo peso molecular podem ser obtidas a partir do tratamento do amido com ácido na presença de álcool anidro. Neste trabalho, amidos de milho e mandioca foram modificados através da ação ácido-metanólica (0,36% HCl em metanol anidro) por 1,0, 3,0, 5,0 e 8,0 horas a 54 ºC. Os amidos modificados foram analisados quanto às suas características físico-químicas, estruturais e morfológicas. A porcentagem de recuperação dos amidos foi determinada e a solubilidade dos mesmos calculada nas temperaturas de 65,0, 75,0, 85,0 e 95,0 oC. A distribuição do tamanho dos grânulos foi determinada usando microscópio óptico acoplado a sistema de imagem. Análises de microscopia eletrônica de varredura e difração de raios-X foram realizadas. O teor de amilose foi determinado a partir de método colorimétrico. A viscosidade intrínseca foi determinada usando-se viscosímetro Cannon Fenske no 50. A distribuição do peso molecular dos amidos foi determinada por Cromatografia de Exclusão por Tamanho de Alta Performance (HPSEC). As propriedades térmicas e de pasta foram analisadas através de Calorímetro Diferencial de Varredura (DSC) e Rápido Visco Analisador (RVA), respectivamente. O rendimento médio foi de 97 e 96% para os amidos de milho e mandioca, respectivamente, sendo que não houve diferença significativa entre os rendimentos obtidos para amidos tratados em diferentes tempos de reação... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: XV Starch modifications have the purpose of improving their technological characteristics and extend their industrial and commercial uses. Modified starches by acid can be used in confectionary production, synthesizing fat replacements and pharmaceutical industry. As the acid concentration and reaction time increase, the yield of acid-modified starch decreases. The maximum conversion of starch with minimal production of low molecular weight dextrins can be obtained by treatment of starch with acid in the presence of anhydrous alcohol. In this work, corn and cassava starch were modified by the methanolic acid action (0,36% HCl in anhydrous methanol) for 1, 3, 5 and 8 hours at 54ºC. The modified starch's physical-chemical properties, structure and morphological characteristics were analysed. The percentage of the starch recovery was determined and the solubility was calculated in the 65, 75, 85 and 95ºC temperatures. The size distribution of granules was determined using an optic microscope with an imaging system. Scanning electron microscope analysis and X-ray diffraction were also performed. The amylose content was determined by the colorimetric method. The intrinsic viscosity was determined using Cannon Fenske viscosimeter nº 50. The molecular weight distribution of starch was determined by High Performance Size Exclusion Cromatography (HPSEC). The thermal and pasting properties were analysed by Differential Scanning Calorimetry (DSC) and Rapid Visco-Analyser (RVA). The average yield was 97 and 96% for the corn and cassava starch, respectively, with no significant variation in yields for different reaction times. The solubility of the starches increased with the temperature and after 1 hour of hydrolysis, reached high values such as 86% (corn) and 94% (cassava) at 95oC... (Complete abstract, click electronic address below). / Mestre
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Bioprospec??o de extratos metan?licos de macroalgas marinhas do litoral do Rio Grande do Norte: avalia??o das atividades anticoagulante, antioxidante e antiproliferativaGomes, Dayanne Lopes 31 July 2012 (has links)
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Previous issue date: 2012-07-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Seaweeds are organisms known to exhibit a variety of biomolecules with
pharmacological properties. The coast of Rio Grande do Norte has over 100 species
of seaweeds, most of them not yet explored for their pharmacological potential.
Sugars and phenolic compounds are the most studied of these being assigned a
range of biological properties, such as anticoagulant , antiinflammatory, antitumor
and antioxidant activities. In this work, we obtained methanolic extracts from thirteen
seaweeds of the coast of Rio Grande do Norte (Dictyota cervicornis; Dictiopterys
delicatula; Dictyota menstruallis; D. mertensis; Sargassum filipendula; Spatoglossum
schr?ederi; Acanthophora specifera; Botryocladia occidentalis; Caulerpa
cupresoides; C. racemosa; C. prolifera; C. sertularioides e Codium isthmocladum).
They were evaluated as anticoagulant and antioxidant drugs, as well as
antiproliferative drugs against the tumor cell line HeLa. None of the methanolic
extracts showed anticoagulant activity, but when they were evaluated as antioxidant
drugs all of extracts showed antioxidant activity in all tests performed (total
antioxidant capacity, sequestration of superoxide and hydroxyl radicals, ferric
chelation and reductase activity), especially the algae D. mentrualis, D. cilliolata and
C. prolifera, who had the greatest potential to donate electrons.In addition, the ability
of iron ions chelation appears as the main antioxidant mechanism of the methanolic
extracts of these seaweeds mainly for the extract of the C. racemosa seaweed, which
reached almost 100% activity. In the MTT assay, all extracts showed inhibitory
activity at different levels againts HeLa cells. Moreover, D. cilliolata (MEDC) and D.
menstrualis (MEDM) extracts showed specific activity to this cell line, not inhibiting
the viability of 3T3 normal cell line, so they were chosen for detailing the
antiproliferative mechanism of action. Using flow cytometry, fluorescence microscopy
and in vitro assays we demonstrated that MEDC and MEDM induced apoptosis in
HeLa cells by activation of caspases 3 and 9 and yet, MEDC induces cell cycle arrest
in S phase. Together, these results showed that the methanolic extracts of brown
seaweed D. menstrualis and D. cilliolata may contain agents with potential use in
combatting cells from human uterine adenocarcinoma. This study also points to the
need for more in-depth research on phytochemical and biological context to enable
the purification of biologically active products of these extracts / Macroalgas marinhas s?o organismos conhecidos por apresentar uma diversidade
de biomol?culas com propriedades farmacol?gicas. O litoral do Rio Grande do Norte
apresenta mais de 100 esp?cies de macroalgas marinhas, a maioria delas ainda n?o
explorada quanto ao seu potencial farmacol?gico. A??cares e compostos fen?licos
s?o os compostos de macroalgas marinhas mais estudados, sendo atribu?da a estes
uma gama de propriedades biol?gicas, como: atividade anticoagulante, antiinflamat?ria,
antitumoral e antioxidante. Neste trabalho, foram obtidos extratos
metan?licos de treze algas do litoral do Rio Grande do Norte (Dictyota cervicornis;
Dictiopterys delicatula; Dictyota menstruallis; Dictyota mertensis; Sargassum
filipendula; Spatoglossum schr?ederi; Acanthophora specifera;Botryocladia
occidentalis;Caulerpa cupresoides; C. racemosa; C. prolifera; C. sertularioides e
Codium isthmocladum), e esses foram avaliados quanto ao seu potencial
anticoagulante, antioxidante e antiproliferativo. Nenhum dos extratos metan?licos
apresentaram atividades anticoagulante, por?m quando avaliados com rela??o ao
potencial antioxidante todos os extratos apresentaram atividade em quase todos os
testes realizados (capacidade antioxidante total, sequestro de radicais super?xido e
hidroxila, quela??o f?rrica e atividade redutora). Os extratos apresentaram
resultados mais expressivos no teste de quela??o f?rrica, principalmente para o
extrato da alga C. racemosa que chegou a quase 100% de atividade. Destaca-se
tamb?m a capacidade de doar el?trons dos extratos, em especial, dasalgas D.
mentrualis,D. cilliolata e C. prolifera que apresentaram os maiores potenciais.
Nosestudos de citotoxidade, todos os extratos apresentaram atividades em
diferentes n?veis frente as c?lulas tumorais HeLa, entretanto, os extratos de D.
cilliolata (MEDC) e D. menstrualis (MEDM) apresentaram atividade espec?fica para
esta linhagem celular, n?o apresentando citotoxidadepara as c?lulas3T3. Estudos
com estes dois extratos utilizando t?cnicas de citometria de fluxo, microscopia de
fluoresc?ncia e testes in vitro mostraram que MEDC e MEDM induzem a apoptose
em c?lulas HeLa atrav?s da ativa??o das caspases 3 e 9 e ainda, MEDC induz a
parada do ciclo celular na fase S. Juntos, esses resultados mostraram que os
extratos metan?licos de algas marrom D. mentrualis e D. cilliolata podem conter
agentes com potencial utiliza??o no combate de c?lulas de adenocarcinoma uterino
humano. O presente estudo tamb?m aponta para a necessidade de investiga??es
mais aprofundadas no ?mbito fitoqu?mico e biol?gico para se identificar produtos
biologicamente ativos presentes nos extratos
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Evaluación in vitro del efecto antibacteriano y citotóxico de los extractos metanólicos de Rubus idaeus (Frambuesa), Vaccinium myrtillus (Arándano azul) y Fragaria ananassa (Fresa) sobre cepas de Streptococcus mutans (ATCC®25175) y Streptococcus sanguinis (ATCC®10556) / In vitro evaluation of antibacterial and cytotoxic effect of Rubus idaeus (Raspberry), Vaccinium myrtillus (Blueberry) and Fragaria ananassa (Strawberry) methanolic extracts against Streptococcus mutans (ATCC®25175) and Streptococcus sanguinis (ATCC®10556) strainsNatividad Hilares, Paul Alberto, Russo Cami, Dominique Zuleik 02 December 2021 (has links)
Objetivo: Evaluar el efecto antibacteriano y citotóxico in vitro de los extractos metanólicos de Rubus idaeus (Frambuesa), Vaccinium myrtillus (Arándano azul) y Fragaria ananassa (Fresa) sobre cepas de Streptococcus mutans (ATCC®25175) y Streptococcus sanguinis (ATCC®10556).
Métodos: Se preparó un extracto metanólico por cada fruto. Se realizaron 10 repeticiones para cada grupo de extracto en cada caso. Se utilizó Clorhexidina al 2% como control positivo. Las propiedades antibacterianas de cada extracto se determinaron mediante el método de difusión en pozo. La concentración mínima inhibitoria (CMI) fue determinada mediante el método de microdilución y la citotoxicidad se analizó mediante la prueba de reducción de MTT, utilizando una línea celular MDCK.
Resultados: El extracto metanólico de arándano azul (Vaccinium myrtillus) tuvo el mayor efecto antibacteriano con un resultado de 30.44 ± 5.72 mm frente a Streptococcus mutans y de 29.33 ± 6.13 mm frente a Streptococcus sanguinis. Los extractos metanólicos de frambuesa, arándano azul y fresa obtuvieron una concentración mínima inhibitoria (CMI) frente a Streptococcus mutans de 0.8 µg/ml, 1.6 µg/ml y 3.1 µg/ml respectivamente; y los extractos metanólicos de arándano azul y fresa frente a Streptococcus sanguinis obtuvieron 3.1 µg/ml y 12.5 µg/ml respectivamente. Los ensayos de viabilidad celular demostraron una baja citotoxicidad de los extractos a altas concentraciones. La viabilidad celular fue más alta para los extractos de Arándano azul y Fresa con 98.2%.
Conclusiones: Los hallazgos evidencian las propiedades antibacterianas de los extractos metanólicos de Rubus idaeus (Frambuesa), Vaccinium myrtillus (Arándano azul) y Fragaria ananassa (Fresa) frente a los microorganismos previamente mencionados. No se evidenció citotoxicidad de los extractos a altas concentraciones. / Objective: Evaluate the in vitro antibacterial and cytotoxic effect of Rubus idaeus (Raspberry), Vaccinium myrtillus (Blueberry) and Fragaria ananassa (Strawberry) methanolic extracts against Streptococcus mutans (ATCC®25175) and Streptococcus sanguinis (ATCC®10556) strains.
Methods: A methanolic extract was prepared for each fruit. Ten independent samples were made for each group of extract. 2% Chlorhexidine was used as a positive control. Antibacterial activity of each methanolic extract was determined by the well diffusion method. The minimum inhibitory concentration (MIC) was established by the microdilution method. Cytotoxicity was analyzed by the MTT reduction test, using a MDCK cell line.
Results: The methanolic extract of blueberry (Vaccinium myrtillus) had the highest antibacterial effect with a result of 30.44 ± 5.72 mm against Streptococcus mutans and 29.33 ± 6.13 mm against Streptococcus sanguinis. The methanolic extracts of raspberry, blueberry and strawberry obtained a minimum inhibitory concentration (MIC) against Streptococcus mutans of 0.8 µg/ml, 1.6 µg/ml and 3.1 µg/ml respectively; and the methanolic extracts of blueberry and strawberry against Streptococcus sanguinis obtained 3.1 µg/ml and 12.5 µg/ml respectively. Cell viability assays demonstrated low cytotoxicity of the methanolic extracts at very high concentrations. Cell viability for blueberry and strawberry methanolic extracts was the highest with 98.2%.
Conclusions: The findings evidence the antibacterial properties of methanolic extracts of Rubus idaeus (Raspberry), Vaccinium myrtillus (Blueberry) and Fragaria ananassa (Strawberry) against the previously mentioned microorganisms. The methanolic extracts didn’t show cytotoxicity at high concentrations. / Tesis
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Inibição do sistema quorum sensing AI-1 por Capsicum frutescens e Capsicum annuum em bactérias Gram-negativas / Inhibition of AI-1 quorum-sensing system by Capsicum frutescens and Capsicum annuum in Gram-negative bacteriaRivera, Milagros Liseth Castillo 22 March 2018 (has links)
A inibição do quorum sensing (QS) altera a comunicação bacteriana, reduzindo a expressão de fatores de virulência e a formação de biofilmes, o que pode conferir menor pressão seletiva em comparação aos antibióticos tradicionais. As frutas e hortaliças constituem uma fonte rica em compostos com propriedades potenciais de inibição do QS. Entretanto, há pouca referência sobre o potencial de pimentas do gênero Capsicum e de seus compostos isolados como inibidores do QS. Esse trabalho teve como objetivo avaliar o efeito de extratos orgânicos obtidos das variedades de pimenta-malagueta e pimentão vermelho sobre o sistema QS dependente do sinalizador AI-1 (acil homoserina lactona - AHL) em bactérias Gram-negativas. Os extratos foram obtidos por extração em fase sólida e separados em uma fração metanólica e outra amônica; sendo os compostos característicos identificados e quantificados por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana dos extratos foi avaliada pela determinação da concentração inibitória mínima (MIC) e pela curva de crescimento de Chromobacterium violaceum ATCC 12472, Serratia liquefaciens MG1 e Pseudomonas aeruginosa PAO1. O efeito anti-QS dos extratos foi avaliado pelos testes de difusão em ágar e quantificação da produção de violaceína em meio líquido por C. violaceum e sobre a formação de biofilme, avaliado pelo ensaio de cristal violeta e microscopia confocal, em S. liquefaciens e P. aeruginosa nas temperaturas 30 ºC e 37 ºC. Os resultados obtidos pela CLAE indicaram que o extrato metanólico de pimenta-malagueta (EMPM) continha capsaicinoides como a capsaicina e dihidrocapsaicina, luteolina e outros compostos não identificados; já o extrato amônico desta não continha os compostos capsaicinoides. Ambos os extratos de pimentão vermelho continham luteolina e compostos não identificados, mas não apresentaram capsaicinoides. Como o EMPM era representativo dos demais extratos, por conter tanto capsaicinóides quanto luteolina, o foco deste trabalho foi avaliar os efeitos do EMPM sobre fenótipos microbianos nas concentrações 5; 2,5; 1,25 e 0,625 mg/ml, além de utilizar a capsaicina como controle comparativo em concentrações equivalentes às do extrato (25, 50 e 100 µg/ml). Os resultados da atividade antimicrobiana mostraram inibição parcial do crescimento das bactérias nas concentrações sub-MIC (MIC >5 mg/ml) de 5 e 2,5 mg/ml de EMPM. A capsaicina também inibiu parcialmente o crescimento das bactérias a 100 µg/ml, com exceção de S. liquefaciens a 37 ºC, cujo crescimento foi induzido em 50 e 25 µg/ml. A produção de violaceína foi reduzida pelo EMPM a 1,25 e 0,625 mg/ml, sem afetar o crescimento de C. violaceum. Ensaios com C. violaceum CV026, estirpe biosensora capaz de produzir o pigmento na presença de AI-1 exógeno, sugerem que o possível mecanismo de atuação do extrato sobre o sistema QS em C. violaceum 12472 é sobre a síntese do sinalizador, já que não foi observada inibição da produção de violaceína em CV026 pelo extrato. Contrariamente, a capsaicina incrementou a produção do pigmento na estirpe 12472, mas ensaios com a estirpe CV026 indicaram que a capsaicina não atua como sinalizador do QS, uma vez que esta não induziu a produção de violaceína nesta estirpe. Já a formação de biofilme foi incrementada na presença do EMPM, sendo consideravelmente maior em P. aeruginosa a 30 ºC. Igualmente, observou-se indução da formação de biofilme por capsaicina em S. liquefaciens (37 ºC) e P. aeruginosa (30 ºC). Porém, a capsaicina não teve efeito sobre a formação de biofilme de S. liquefaciens quando cultivada a 30 ºC, nem P. aeruginosa a 37 ºC. Os resultados revelam que a produção de violaceína em C. violaceum ATCC 12472 é inibida pelo EMPM, mas não pela capsaicina. Já, o EMPM e a capsaicina, de forma geral, não inibem a formação de biofilme de S. liquefaciens MG1 nem P. aeruginosa PAO1. Outros estudos são necessários para elucidar os mecanismos pelos quais o EMPM e a capsaicina agem sobre os fenótipos avaliados neste trabalho. / Quorum sensing inhibition alters bacterial communication by reducing virulence factors expression and biofilm formation, exerting less selective pressure compared to antibiotics. Fruits and vegetables are rich sources of compounds with potential QS-inhibition properties. However, there are few references about the potential of peppers belonging to the genus Capsicum and its isolated compounds as QS inhibitors. This study aimed to assess the effect of organic extracts obtained from Capsicum varieties, pimenta-malagueta (red chili) and pimentão vermelho (red bell pepper), on the AI-1 dependent QS system. The extracts were obtained by solid phase extraction and split into a methanolic and an ammonic fraction. Characteristic compounds were identified and quantified by high performance liquid chromatography (HPLC). The antimicrobial activity of the extracts was assessed by determining the minimal inhibitory concentration (MIC) and the growth curve of Chromobacterium violaceum ATCC 12472, Serratia liquefaciens MG1 and Pseudomonas aeruginosa PAO1. The anti-QS effect of the extracts was evaluated by the agar diffusion assay and the quantification of violacein production was assessed in liquid medium by C. violaceum, as well as in the biofilm formation test determined by the crystal violet assay and confocal microscopy with S. liquefaciens and P. aeruginosa at 30 ºC and 37 ºC. HPLC results showed that the methanolic extract of pimenta-malagueta (EMPM) contained capsaicinoids such as capsaicin and dihidrocapsaicin, luteolin and other unidentified compounds in lower concentrations; while its ammonic extract did not have capsaicinoids. Both pimentão vermelho extracts contained luteolin and other unidentified compounds in low concentrations, but they did not contain capsaicinoids. As EMPM was representative among the extracts because it contained capsaicinoids and luteolin, the focus of this work was to assess the effect of EMPM over microbial phenotypes at concentrations of 5, 2.5, 1.25 and 0.625 mg/ml, using capsaicin as a comparative control at equivalent concentrations to those in EMPM (25, 50 and 100 µg/ml). Antimicrobial activity assays showed a partial inhibition growth of bacteria at sub-MIC concentrations (MIC >5 mg/ml) of EMPM at 5 and 2.5 mg/ml. Similarly, capsaicin partially inhibited bacterial growth at 100 µg/ml, except for S. liquefaciens at 37 ºC in which growth was induced at 50 and 25 µg/ml. Violacein production was reduced by EMPM at 1,25 and 0,625 mg/ml without affecting C. violaceum growth. Assays with C. violaceum CV026, a biosensor strain that produces violacein in the presence of exogenous AI-1, suggest that EMPM reduced violacein production in C. violaceum 12472 by interfering with the AI-1 synthesis. In contrast, capsaicin incremented violacein synthesis in strain 12472, but experiments with strain CV026 revealed that capsaicin does not function as an analog of AI-1. Biofilm formation was increased in EMPM presence, being remarkably superior in P. aeruginosa cultivated at 30 ºC, as opposed to cultivation at 37 ºC. Similarly, capsaicin induced biofilm formation in S. liquefaciens (37 ºC) and P. aeruginosa (30 ºC). However, capsaicin did not affect biofilm formation on S. liquefaciens cultured at 30 ºC, neither on P. aeruginosa at 37 ºC. These results show that violacein production in C. violaceum ATCC 12472 is inhibited by EMPM, but not by capsaicin. In general, EMPM and capsaicin did not inhibit biofilm formation in S. liquefaciens MG1 neither in P. aeruginosa PAO1. More studies are necessary to elucidate the mechanisms by which EMPM and capsaicin affect the studied phenotypes in this work.
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The Effects of Crude Methanolic Extract of Commelina benghalensis Linn on the Expression of Apoptotic and Cell Division Cycle Genes in Jurkat T and Wil-2 NSCancer Cell Lines.Mbazima, Vusi G. January 2009 (has links)
Thesis (Ph.D. (Biochemistry)) --University of Limpopo, 2009 / Commelina benghalensis Linn is used in traditional medicine in several Asian
and African countries for the treatment of various ailments such as stomach
irritations, burns, sore throat and feet, diarrhoea and as an anti-inflammatory
agent. Recently, our laboratory showed that the crude methanolic extract of
Commelina benghalensis L (CMECB) exhibits growth inhibitory and proapoptotic
effects in Jurkat T and Wil-2 NS cancer cell lines. In this study, the
precise molecular mechanism(s) associated with CMECB-induced growth
inhibitory and apoptosis inducing effects in Jurkat T and Wil-2 NS cell lines
were investigated. This was achieved by investigating the effects of the
extract on the cell division cycle distribution profile as well as its effects on
various cell division cycle and apoptosis regulatory genes. Ground stems of C.
benghalensis L were extracted with absolute methanol to obtain a crude
extract. To assess the effect of CMECB on cancer cell growth, experimental
cell cultures were exposed to various concentrations (0 to 600 μg/ml) of
CMECB for up to 72 hours. The results demonstrated a significant reduction in
cell viability and inhibition of proliferation of experimental cell cultures as
determined by the trypan blue dye exclusion assay and the Coulter counter
method, respectively. Analysis of nuclear morphological changes in cells
stained with Hoechst 33258 confirmed apoptosis as the mode of cell death
that is associated with the growth inhibitory effects of CMECB in both the
Jurkat T and Wil-2 NS cell lines. This assertion was based on the observed
presence of nuclear morphological changes such as chromatin condensation
and fragmentation and apoptotic bodies in cells exposed to CMECB. In order
to get an insight on the pro-apoptotic mechanisms of CMECB, Western blot
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and quantitative real-time PCR (qrt-PCR) were used to investigate the
expression profiles of various apoptosis and cell division cycle regulatory
genes. Qrt-PCR results showed a lack of a clear up- and/or down-regulatory
effects of CMECB on the mRNA expression levels of bax and bcl-2 in both
Jurkat T and Wil-2 NS cells.
Western blot analyses demonstrated that CMECB induced apoptosis by
facilitating Bax protein translocation from the cytosol to the mitochondria in
both Jurkat T and Wil-2 NS cells. In addition, CMECB down-regulated Bcl-2
protein expression which, as a result, led to the shift in the Bax/Bcl-2 protein
ratio at certain time points and concentration in both Jurkat T and Wil-2 NS
cells. The modulation of the Bcl-2 family members led to mitochondrial
cytochrome c release into the cytosol and activation of caspases-9 and -3; this
was also confirmed by caspase activity assays and eventual degradation of
PARP. Furthermore, CMECB induced Jurkat T and Wil-2 NS cell division
cycle arrest at the G2/M phase as determined by flow cytometric analysis.
Western blot analyses of G2/M phase regulatory proteins demonstrated that
the CMECB-induced cell division cycle arrest was associated with the downregulation
of cyclin B1 and Cdc2 protein expression levels. Western blot
analyses results further revealed that the arrest of Wil-2 NS cells at the G2/M
phase was independent of p21 protein activity. However, Jurkat T cell division
cycle arrest was found to be mediated, in part, by p21. Quantitative real-time
PCR results did not show a clear trend in terms of the down- or up-regulatory
effects of the extracts on the G2/M phase regulatory genes. The CMECBinduced
apoptosis and G2/M arrest was found to occur in a p53-independent
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manner due to the lack and down-regulation of p53 protein levels in both
Jurkat T and Wil-2 NS cells, respectively. In conclusion, CMECB induces its
anticancer activity by inducing G2/M phase arrest and mitochondrial-mediated
apoptosis independent of p53 protein activity. Although the study did not
perform in vivo experiments to ascertain the efficacy of extracts of CMECB
against specific tumour types in animal models, the present findings somehow
validate the traditional use of C. benghalensis L as an anticancer agent. A
more definitive study needs to be done to ascertain this assertion. / National Research Foundation and the
University of Limpopo research office
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Cecropia pachystachya Trécul como adjuvante no tratamento do diabetes melitoAragão, Danielle Maria de Oliveira 27 February 2015 (has links)
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Previous issue date: 2015-02-27 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Diabetes melito engloba uma série de alterações metabólicas que acarretam um estado crônico de hiperglicemia. Buscando novas alternativas para seu tratamento, muitas espécies de plantas conhecidas na medicina popular pelas propriedades hipoglicemiantes têm sido avaliadas. Entre essas espécies está Cecropia pachystachya Trécul (URTICACEAE), uma planta nativa do Brasil, cujos nomes populares são embaúba, imbaíba, umbaúba, árvore-de-preguiça, barbeira, torém. Nesse contexto, o presente estudo teve como objetivo avaliar o potencial hipoglicemiante, antioxidante e toxicológico das folhas de Cecropia pachystachya. Inicialmente foram preparados dois extratos das folhas dessa espécie, metanólico (EM) e em acetato de etila (EAE). Ambos os extratos foram submetidos à análise quantitativa dos marcadores moleculares e, posteriormente, foi avaliado o efeito hipoglicemiante de cada um deles. EAE foi ncorporado a uma formulação farmacêutica líquida (FF). EM, EAE e FF foram utilizados para o tratamento de ratos
da linhagem Wistar normais e induzidos ao diabetes por estreptozotocina. A evolução desses tratamentos foi avaliada através de medidas mensais de glicemias de jejum, além de acompanhamento de peso corporal e consumos de água e ração. Ao final de seis meses, os animais foram eutanasiados e amostras de sangue e órgãos foram coletadas para análises bioquímicas, antioxidante e histopatológica.
Foram ainda avaliados os efeitos de FF após a interrupção do tratamento e o efeito do pré-tratamento com FF na indução de ratos com estreptozocina. A análise do perfil cromatográfico de EM e EAE revelou a presença de três marcadores moleculares, ácido clorogênico, isoorientina e orientina. Na análise quantitativa foram observados maiores teores dos flavonoides isoorientina e orientina em EAE. Os extratos padronizados foram administrados em ratos diabéticos ao longo de seis meses, mostrando reduções significativas tanto para EM (56%) quanto para EAE (69%). No entanto, EAE apresentou redução significativa da glicemia já no primeiro mês de tratamento, além de apresentar resultados relevantes em todos os parâmetros antioxidantes avaliados. O tratamento crônico com FF proporcionou uma redução de aproximadamente 70% da glicemia de jejum, ao final dos seis meses, em relação à glicemia inicial desses mesmos animais. Após a interrupção desse tratamento, as glicemias de animais diabéticos foram mantidas em níveis normais. Além disso, o pré-tratamento de ratos normais com FF promoveu proteção sobre as células B-pancreáticas durante a indução do diabetes utilizando estreptozocina. Os resultados mostraram que a FF desenvolvida a partir da espécie Cecropia pachystachya pode ser indicada na preparação de um fitoterápico para auxiliar no tratamento do diabetes melito. / Diabetes mellitus comprises a series of metabolic changes that lead to a chronic state of hyperglycemia. Seeking new alternatives for their treatment, many species of plants known in folk medicine for hypoglycemic properties have been evaluated. Among these species is Cecropia pachystachya Trécul (Urticaceae), a plant native to Brazil, whose common names are embaúba, imbaíba, umbaúba, tree-of-laziness, barbeira, Torem. In this context, the present study aimed to evaluate the potential hypoglycemic, antioxidant and toxicology of Cecropia leaves pachystachya. Initially were prepared two extracts from the leaves of this species, methanol (EM) and ethyl acetate (EAE). Both extracts were subjected to quantitative analysis of molecula markers and subsequently evaluated the hypoglycemic effect of each. EAE was incorporated into a liquid pharmaceutical formulation (FF). MS, EAE and FF were used for the treatment of normal Wistar rats and streptozotocin-induced diabetes. The evolution of these treatments was evaluated through monthly measurements of fasting glucose, and body weight monitoring and water and feed consumption. After six months, the animals were euthanized and blood samples and organs were collected for biochemical, antioxidant and histopathological analysis. We also assessed the effects of FF after discontinuation of treatment and the effect of pretreatment with inducing FF in rats with streptozocin. Analysis of the chromatographic profile of MS and EAE showed the presence of three molecular markers, chlorogenic, orientin and isoorientina acid. The quantitative analysis showed higher levels of flavonoids orientin isoorientina and in EAE. Standardized extracts were administered to diabetic rats over six months, showing significant reductions for both MS (56%) and against EAE (69%). However, EAE had a significant reduction of blood glucose in the first month of treatment, and provide relevant results in all evaluated parameters antioxidants. Chronic treatment with FF was reduced by approximately 70% of fasting glucose at the end of six months from the initial blood glucose of those animals. After discontinuation of treatment, the glycemia of diabetic animals were maintained at normal levels. In addition,
pretreatment of mice with normal FF provided protection for pancreatic B-cells in diabetes induced using streptozotocin. The results show that FF developed from Cecropia pachystachya species can be indicated in a herbal preparation to aid in the treatment of diabetes mellitus.
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Inibição do sistema quorum sensing AI-1 por Capsicum frutescens e Capsicum annuum em bactérias Gram-negativas / Inhibition of AI-1 quorum-sensing system by Capsicum frutescens and Capsicum annuum in Gram-negative bacteriaMilagros Liseth Castillo Rivera 22 March 2018 (has links)
A inibição do quorum sensing (QS) altera a comunicação bacteriana, reduzindo a expressão de fatores de virulência e a formação de biofilmes, o que pode conferir menor pressão seletiva em comparação aos antibióticos tradicionais. As frutas e hortaliças constituem uma fonte rica em compostos com propriedades potenciais de inibição do QS. Entretanto, há pouca referência sobre o potencial de pimentas do gênero Capsicum e de seus compostos isolados como inibidores do QS. Esse trabalho teve como objetivo avaliar o efeito de extratos orgânicos obtidos das variedades de pimenta-malagueta e pimentão vermelho sobre o sistema QS dependente do sinalizador AI-1 (acil homoserina lactona - AHL) em bactérias Gram-negativas. Os extratos foram obtidos por extração em fase sólida e separados em uma fração metanólica e outra amônica; sendo os compostos característicos identificados e quantificados por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana dos extratos foi avaliada pela determinação da concentração inibitória mínima (MIC) e pela curva de crescimento de Chromobacterium violaceum ATCC 12472, Serratia liquefaciens MG1 e Pseudomonas aeruginosa PAO1. O efeito anti-QS dos extratos foi avaliado pelos testes de difusão em ágar e quantificação da produção de violaceína em meio líquido por C. violaceum e sobre a formação de biofilme, avaliado pelo ensaio de cristal violeta e microscopia confocal, em S. liquefaciens e P. aeruginosa nas temperaturas 30 ºC e 37 ºC. Os resultados obtidos pela CLAE indicaram que o extrato metanólico de pimenta-malagueta (EMPM) continha capsaicinoides como a capsaicina e dihidrocapsaicina, luteolina e outros compostos não identificados; já o extrato amônico desta não continha os compostos capsaicinoides. Ambos os extratos de pimentão vermelho continham luteolina e compostos não identificados, mas não apresentaram capsaicinoides. Como o EMPM era representativo dos demais extratos, por conter tanto capsaicinóides quanto luteolina, o foco deste trabalho foi avaliar os efeitos do EMPM sobre fenótipos microbianos nas concentrações 5; 2,5; 1,25 e 0,625 mg/ml, além de utilizar a capsaicina como controle comparativo em concentrações equivalentes às do extrato (25, 50 e 100 µg/ml). Os resultados da atividade antimicrobiana mostraram inibição parcial do crescimento das bactérias nas concentrações sub-MIC (MIC >5 mg/ml) de 5 e 2,5 mg/ml de EMPM. A capsaicina também inibiu parcialmente o crescimento das bactérias a 100 µg/ml, com exceção de S. liquefaciens a 37 ºC, cujo crescimento foi induzido em 50 e 25 µg/ml. A produção de violaceína foi reduzida pelo EMPM a 1,25 e 0,625 mg/ml, sem afetar o crescimento de C. violaceum. Ensaios com C. violaceum CV026, estirpe biosensora capaz de produzir o pigmento na presença de AI-1 exógeno, sugerem que o possível mecanismo de atuação do extrato sobre o sistema QS em C. violaceum 12472 é sobre a síntese do sinalizador, já que não foi observada inibição da produção de violaceína em CV026 pelo extrato. Contrariamente, a capsaicina incrementou a produção do pigmento na estirpe 12472, mas ensaios com a estirpe CV026 indicaram que a capsaicina não atua como sinalizador do QS, uma vez que esta não induziu a produção de violaceína nesta estirpe. Já a formação de biofilme foi incrementada na presença do EMPM, sendo consideravelmente maior em P. aeruginosa a 30 ºC. Igualmente, observou-se indução da formação de biofilme por capsaicina em S. liquefaciens (37 ºC) e P. aeruginosa (30 ºC). Porém, a capsaicina não teve efeito sobre a formação de biofilme de S. liquefaciens quando cultivada a 30 ºC, nem P. aeruginosa a 37 ºC. Os resultados revelam que a produção de violaceína em C. violaceum ATCC 12472 é inibida pelo EMPM, mas não pela capsaicina. Já, o EMPM e a capsaicina, de forma geral, não inibem a formação de biofilme de S. liquefaciens MG1 nem P. aeruginosa PAO1. Outros estudos são necessários para elucidar os mecanismos pelos quais o EMPM e a capsaicina agem sobre os fenótipos avaliados neste trabalho. / Quorum sensing inhibition alters bacterial communication by reducing virulence factors expression and biofilm formation, exerting less selective pressure compared to antibiotics. Fruits and vegetables are rich sources of compounds with potential QS-inhibition properties. However, there are few references about the potential of peppers belonging to the genus Capsicum and its isolated compounds as QS inhibitors. This study aimed to assess the effect of organic extracts obtained from Capsicum varieties, pimenta-malagueta (red chili) and pimentão vermelho (red bell pepper), on the AI-1 dependent QS system. The extracts were obtained by solid phase extraction and split into a methanolic and an ammonic fraction. Characteristic compounds were identified and quantified by high performance liquid chromatography (HPLC). The antimicrobial activity of the extracts was assessed by determining the minimal inhibitory concentration (MIC) and the growth curve of Chromobacterium violaceum ATCC 12472, Serratia liquefaciens MG1 and Pseudomonas aeruginosa PAO1. The anti-QS effect of the extracts was evaluated by the agar diffusion assay and the quantification of violacein production was assessed in liquid medium by C. violaceum, as well as in the biofilm formation test determined by the crystal violet assay and confocal microscopy with S. liquefaciens and P. aeruginosa at 30 ºC and 37 ºC. HPLC results showed that the methanolic extract of pimenta-malagueta (EMPM) contained capsaicinoids such as capsaicin and dihidrocapsaicin, luteolin and other unidentified compounds in lower concentrations; while its ammonic extract did not have capsaicinoids. Both pimentão vermelho extracts contained luteolin and other unidentified compounds in low concentrations, but they did not contain capsaicinoids. As EMPM was representative among the extracts because it contained capsaicinoids and luteolin, the focus of this work was to assess the effect of EMPM over microbial phenotypes at concentrations of 5, 2.5, 1.25 and 0.625 mg/ml, using capsaicin as a comparative control at equivalent concentrations to those in EMPM (25, 50 and 100 µg/ml). Antimicrobial activity assays showed a partial inhibition growth of bacteria at sub-MIC concentrations (MIC >5 mg/ml) of EMPM at 5 and 2.5 mg/ml. Similarly, capsaicin partially inhibited bacterial growth at 100 µg/ml, except for S. liquefaciens at 37 ºC in which growth was induced at 50 and 25 µg/ml. Violacein production was reduced by EMPM at 1,25 and 0,625 mg/ml without affecting C. violaceum growth. Assays with C. violaceum CV026, a biosensor strain that produces violacein in the presence of exogenous AI-1, suggest that EMPM reduced violacein production in C. violaceum 12472 by interfering with the AI-1 synthesis. In contrast, capsaicin incremented violacein synthesis in strain 12472, but experiments with strain CV026 revealed that capsaicin does not function as an analog of AI-1. Biofilm formation was increased in EMPM presence, being remarkably superior in P. aeruginosa cultivated at 30 ºC, as opposed to cultivation at 37 ºC. Similarly, capsaicin induced biofilm formation in S. liquefaciens (37 ºC) and P. aeruginosa (30 ºC). However, capsaicin did not affect biofilm formation on S. liquefaciens cultured at 30 ºC, neither on P. aeruginosa at 37 ºC. These results show that violacein production in C. violaceum ATCC 12472 is inhibited by EMPM, but not by capsaicin. In general, EMPM and capsaicin did not inhibit biofilm formation in S. liquefaciens MG1 neither in P. aeruginosa PAO1. More studies are necessary to elucidate the mechanisms by which EMPM and capsaicin affect the studied phenotypes in this work.
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Efeito da modificação ácido-metanólica nas características estruturais e fisico-químicas de amidos de milho e mandiocaFerrini, Luara Mirela Kurachi [UNESP] 14 December 2006 (has links) (PDF)
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ferrini_lmk_me_sjrp.pdf: 1736164 bytes, checksum: 88558b2eb0c1b58e46819cb752e96274 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / XIII Modificações de amidos têm como objetivo melhorar suas características tecnológicas e estender sua utilização industrial e comercial. Amidos modificados por ácido podem ser usados na produção de confeitos, como substitutos de gordura e na indústria farmacêutica. O rendimento do amido ácido-modificado diminui quanto maior a concentração de ácido e tempo de reação. Maiores conversões de amido com menor produção de dextrinas de baixo peso molecular podem ser obtidas a partir do tratamento do amido com ácido na presença de álcool anidro. Neste trabalho, amidos de milho e mandioca foram modificados através da ação ácido-metanólica (0,36% HCl em metanol anidro) por 1,0, 3,0, 5,0 e 8,0 horas a 54 ºC. Os amidos modificados foram analisados quanto às suas características físico-químicas, estruturais e morfológicas. A porcentagem de recuperação dos amidos foi determinada e a solubilidade dos mesmos calculada nas temperaturas de 65,0, 75,0, 85,0 e 95,0 oC. A distribuição do tamanho dos grânulos foi determinada usando microscópio óptico acoplado a sistema de imagem. Análises de microscopia eletrônica de varredura e difração de raios-X foram realizadas. O teor de amilose foi determinado a partir de método colorimétrico. A viscosidade intrínseca foi determinada usando-se viscosímetro Cannon Fenske no 50. A distribuição do peso molecular dos amidos foi determinada por Cromatografia de Exclusão por Tamanho de Alta Performance (HPSEC). As propriedades térmicas e de pasta foram analisadas através de Calorímetro Diferencial de Varredura (DSC) e Rápido Visco Analisador (RVA), respectivamente. O rendimento médio foi de 97 e 96% para os amidos de milho e mandioca, respectivamente, sendo que não houve diferença significativa entre os rendimentos obtidos para amidos tratados em diferentes tempos de reação... . / XV Starch modifications have the purpose of improving their technological characteristics and extend their industrial and commercial uses. Modified starches by acid can be used in confectionary production, synthesizing fat replacements and pharmaceutical industry. As the acid concentration and reaction time increase, the yield of acid-modified starch decreases. The maximum conversion of starch with minimal production of low molecular weight dextrins can be obtained by treatment of starch with acid in the presence of anhydrous alcohol. In this work, corn and cassava starch were modified by the methanolic acid action (0,36% HCl in anhydrous methanol) for 1, 3, 5 and 8 hours at 54ºC. The modified starch's physical-chemical properties, structure and morphological characteristics were analysed. The percentage of the starch recovery was determined and the solubility was calculated in the 65, 75, 85 and 95ºC temperatures. The size distribution of granules was determined using an optic microscope with an imaging system. Scanning electron microscope analysis and X-ray diffraction were also performed. The amylose content was determined by the colorimetric method. The intrinsic viscosity was determined using Cannon Fenske viscosimeter nº 50. The molecular weight distribution of starch was determined by High Performance Size Exclusion Cromatography (HPSEC). The thermal and pasting properties were analysed by Differential Scanning Calorimetry (DSC) and Rapid Visco-Analyser (RVA). The average yield was 97 and 96% for the corn and cassava starch, respectively, with no significant variation in yields for different reaction times. The solubility of the starches increased with the temperature and after 1 hour of hydrolysis, reached high values such as 86% (corn) and 94% (cassava) at 95oC... (Complete abstract, click electronic address below).
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Caractérisations chimiques et biologiques d’extraits de plantes aromatiques et médicinales oubliées ou sous-utilisées de Midi-Pyrénées (France) et de Chongqing (Chine) / Chemical and biological characterisation of extracts from forgotten or underutilised medicinal and aromatic plants from Midi-Pyrénées (France) and Chongqing (China) regionsZhao, Tianming 12 May 2014 (has links)
Les régions de Midi-Pyrénées (France) et de Chongqing (Chine) sont riches en plantes aromatiques et médicinales dites oubliées (ou médiévales). Afin de valoriser pleinement les différentes bio-molécules extractibles de ces plantes, le concept de MAP-raffinerie a été créé et appliqué à une sélection de plantes issues de ces deux régions. Plusieurs technologies d’extraction utilisant l’eau comme solvant vert (hydrodistillation, distillation à la vapeur et extraction par eau sub-critique) ont ainsi été employées et leur impact tant sur la composition des huiles essentielles que sur la récupération des molécules anti-oxydantes a été évalué. Dans un premier temps, une liste de plantes aromatiques et médicinales oubliées, voire sous-utilisées dans les deux régions a été établie selon des règles de sélection prédéfinies. Six plantes modèles de la région de Midi-Pyrénées (Tussilago farfara L., Calendula arvensis L., Robinia pseudoacacia L., Geranium robertianum L., Cytisus scoparius L. et Spartium junceum L.) et trois plantes de la région de Chongqing (Tussilago farfara L., Citrus aurantium L. et Saussurea costus) ont finalement été retenues. Puis, le concept de MAP-raffinerie a été appliqué à ces plantes afin d’étudier leur possible valorisation globale. L’étude des compositions chimiques des extraits volatils des racines de Tussilago farfara L. et de Calendula arvensis L., ainsi que des boutons de fleurs de Spartium junceum L. a été réalisée par GC et GC-MS pour la première fois. Les principaux composés chimiques dans l’extrait volatil de racines de Tussilago farfara L. étaient des hydrocarbures sesquiterpéniques et des composés aliphatiques tandis que les principaux composés chimiques dans l’extrait volatil de racines de Calendula arvensis L. étaient des sesquiterpènes oxygénés, des monoterpènes oxygénés et des diterpènes oxygénés. L’extrait volatil de boutons de fleurs de Spartium junceum L. était principalement composé de composés aliphatiques. Par ailleurs, les résultats de l’évaluation des capacités anti-oxydantes des extraits (par les tests DPPH, ABTS, FRAP, ORAC et Folin-Ciocalteu) ont montrés que plusieurs plantes comme Cytisus scoparius L., Tussilago farfara L., Citrus aurantium L. ou Robinia pseudoacacia L. pourraient être des sources potentielles d’anti-oxydants naturels. D’un point de vue technologique, les comparaisons de l’utilisation de l’hydrodistillation (HD), de la distillation à la vapeur (SD) et de l’extraction par eau sub-critique (SWE) ont montrées que si la HD et la SD ont des effets limités sur la composition des huiles essentielles, la HD semble être une méthode plus efficace pour la récupération des composés anti-oxydants à partir des résidus de distillation que la SD tandis que la SWE s’avère être une technologie prometteuse pour l’extraction directe de ces molécules à partir des plantes. Si la composition minérale de l’eau lors de l’hydrodistillation n’a que des effets très limités sur les rendements d’extraction, les teneurs en ions calcium et bicarbonate des eaux ont par contre des effets décroissants significatifs sur la capacité anti-oxydante et sur la teneur phénolique totale des extraits aqueux et méthanoliques. Au vue de ces résultats, un concept amélioré de MAP-raffinerie a été développé en intégrant une extraction à l’eau sub-critique pour l’extraction des composés anti-oxydants des résidus d’extraction primaire. Selon ce nouveau concept, cinq extraits peuvent être obtenus à partir des matières végétales: un extrait volatil, un extrait aqueux, un extrait méthanolique, un extrait à l’eau sub-critique et in fine un résidu solide. Les premiers résultats ont montrés que la "MAP-raffinerie améliorée" augmente de manière significative la récupération des antioxydants par rapport à la MAP-raffinerie originale et permet d’envisager une valorisation plus facile du résidu solide en agro-matériaux du fait de sa faible teneur en eau résiduelle. / In both Midi-Pyrénées region (France) and Chongqing region (China), there are rich and underutilized medicinal and aromatic plants (MAP). Aiming at fully exploiting different molecules in these plants, the concept of MAP-refinery was developed and applied to several underutilized medicinal and aromatic plants in these two regions. Several water-based green extraction technologies of natural products (e.g. hydrodistillation, steam distillation and subcritical water extraction) were also investigated to look at their effects on essential oil composition and antioxidants recovery from selected plants. Firstly, lists of forgotten or underutilized medicinal and aromatic plants in both regions were established according to the rules of selection. From the lists, six plants in the Midi-Pyrénées region (Tussilago farfara L., Calendula arvensis L., Robinia pseudoacacia L., Geranium robertianum L., Cytisus scoparius L. and Spartium junceum L.) and three plants in the Chongqing region (Tussilago farfara L., Citrum aurantium L. and Saussurea costus) were finally selected for investigations. Then the MAP-refinery was applied to the selected plants in two regions in order to realise their global valorisation. Volatile extracts composition in the roots of Tussilago farfara L. and Calendula arvensis L., as well as flower buds of Spartium junceum L. were firstly investigated. The main chemical compounds in volatile extract from Tussilago farfara L. roots were sesquiterpene hydrocarbons and aliphatic compounds while main chemical compounds in volatile extract from Calendula arvensis L. roots were oxygenated sesquiterpenes, oxygenated monoterpenes and oxygenated diterpenes. The volatile extract from flower buds of Spartium junceum L. was mainly composed of aliphatic compounds. Antioxidant capacity evaluation results (by DPPH, ABTS, FRAC, ORAC and Folin-Ciocalteu tests) showed that several plant samples like Cytisus scoparius L., Tussilago farfara L., Citrum aurantium L. and Robinia pseudoacacia L. could be potential sources of natural antioxidants. Comparisons of hydrodistillation (HD), steam distillation (SD) and subcritical water extraction (SWE) showed that HD and SD had limited effects on essential oil composition but HD, SD and SWE had significant impacts on the recovery of antioxidants. Hydrodistillation seemed to be a better method for recovery of antioxidant compounds from residues of distillation than steam distillation. However, SWE appeared to be a more efficient method for direct extraction of antioxidant molecules (or phenolic compounds) from plants. In the hydrodistillation process, mineral contents in water were found to have very limited effects on yields of extracts but calcium and bicarbonate ions, had significant decreasing effects on antioxidant capacity and total phenolic content of both aqueous and methanolic extracts. Finally, an improved MAP-refinery was developed. Subcritical water was used for further extraction of antioxidant compounds from residues in original MAP-refinery. In this way, five parts could be obtained from plant materials: volatile extract, aqueous extract, methanolic extract, subcritical water extract and the final residue. The results showed that the improved MAP-refinery significantly increased the recovery of antioxidants compared with original MAP-refinery. This promising process will also allow a better valorisation of the final solid residue due to the lower content of residual water.
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