• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 72
  • 46
  • 26
  • 19
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 3
  • 2
  • 1
  • Tagged with
  • 188
  • 74
  • 39
  • 30
  • 29
  • 25
  • 23
  • 21
  • 19
  • 18
  • 16
  • 16
  • 15
  • 14
  • 13
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Viabilidade de Bifidobacterium animalis subsp. lactis HN019 em fórmulas infantis probióticas durante o armazenamento a 4 ºC / Viability of Bifidobacterium animalis ssp. lactis HN019 in probiotic infant formulas

Ana Lucia Orlandini Pilleggi de Sousa 19 May 2011 (has links)
O objetivo deste trabalho foi estudar a viabilidade de Bifidobacterium animalis subsp. lactis HN019 em fórmulas infantis fermentadas ou não, probióticas durante armazenamento a 4°C. Três matrizes lácteas e três não lácteas (a base de soja) foram utilizadas para a elaboração de produtos fermentados ou não fermentados usando Bifidobacterium animalis subsp. lactis HN019, resultando em doze diferentes fórmulas probióticas para lactentes. O perfil de acidificação foi determinado a 42°C até pH 4,7. Determinações físico-químicas (sólidos totais, proteína, gordura, cinzas, carboidratos, calorias, densidade e pH) foram realizadas e foram focadas as contagens de bactérias viáveis durante o armazenamento refrigerado. A caracterização química dos produtos lácteos e a não lácteos apresentou resultados diferentes, à exceção FSL2, todos estavam de acordo com Codex Alimentarius. O perfil de acidificação de Bifidobacterium animalis subsp. lactis HN019 diferiu conforme a matriz. Durante o armazenamento dos produtos a 4°C, a contagem de bactérias viáveis de acordo com o preconizado, bem como a pós-acidificação, estando em conformidade com as recomendações da legislação brasileira. Processo (fermentação ou adição) e tipo de matriz (lácteos e não lácteos) influenciaram a pós-acidificação e a viabilidade de Bifidobacterium animalis subsp. lactis HN019. As fórmulas para lactentes podem ser considerados bons veículos de Bifidobacterium animalis subsp. lactis HN019. / This study proposed to study infant formulas as vehicles for Bifidobacterium animalis ssp.lactis HNOI9. Three dairy and three non-dairy matrices were employed for the preparation of fermented or unfermented products using Bifidobacterium animalis ssp. lactis HN019 resulting in twelve different probiotic infant formulas. Acidification profile of the probiotic was determined at 42°C until pH 4.7. Physicochemical determination (total solids, protein, fat, ash, carbohydrates and calories, density and pH) was conducted, and counts viable bacteria (in dairy and non dairy infant formulas fermented and unfermented) during cold storage was focused on. The chemical characterization of the dairy and non-dairy matrix showed different results, the exception FSL2, all were in accordance to the Codex Alimentarius. The acidification profile of B. animalis ssp. lactis HN019 differed according to the matrix. During storage of products at 4°C counts of viable bacteria were stable as well as post-acidification, and were in accordance with the recommendations of the Brazilian legislation. Process (fermentation or addition) and matrix type (dairy and non-dairy) influenced post-acidification and viability of B. animalis ssp. lactis BN019 . Infant formulas could be considered good vehicles for Bifidobacterium animalis ssp. lactis HN019.
52

Desenvolvimento de manjar branco potencialmente probiótico / Development of potential probiotic coconut flan

Sabrina Barros de Mattos Corrêa 14 July 2006 (has links)
A ingestão de alimentos que, além de fornecerem a nutrição, promovem a saúde, como os alimentos funcionais adicionados de probióticos, que auxiliam no equilíbrio da microbiota intestinal, é de vital importância. Em virtude do crescente interesse da indústria e da comunidade científica por novos produtos probióticos, o desenvolvimento de uma sobremesa láctea que permita a adição de probióticos, como o manjar branco, é promissor. O presente trabalho visou desenvolver um manjar branco com a adição dos microrganismos potencialmente probióticos, Lactobacillus paracasei subsp. paracasei e/ou Bifidobacterium longum, adicionados isoladamente e em co-cultura, e avaliar o comportamento dos probióticos e as características do produto ao longo do seu armazenamento refrigerado. Quatro tratamentos de manjar branco foram produzidos (com 3 repetições cada): T1 (controle - sem a adição de culturas), T2 (com Bifidobacterium longum), T3 (com Lactobacillus paracasei) e T4 (com B. longum + L. paracasei). O produto foi avaliado sensorialmente (após 7, 14 e 21 dias de armazenamento a 4±1°C, através de escala hedônica estruturada, com 24 provadores não treinados em cada período) e, durante o seu armazenamento por até 28 dias, microbiologicamente quanto à viabilidade dos probióticos e à contagem de contaminantes (coliformes, Escherichia coli, Staphylococcus spp. e bolores e leveduras) e quanto às suas características físico químicas (umidade, pH) e de textura instrumental. Durante o armazenamento dos produtos por 28 dias, as populações médias de L. paracasei aumentaram de 6,6 para 8,6 log UFC/g e de 6,4 para 7,3 log UFC/g, para T3 e T4, respectivamente. B. longum revelou populações sempre entre 7,3 e 7,5 log UFC/g e entre 7,1 e 7,5 log UFC/g para T2 e T4, respectivamente. O manjar T3 resultou em uma redução mais acentuada do pH (p<0,05), mas a umidade não foi significativamente distinta para os diferentes produtos (p>0,05). A firmeza de todos os tratamentos de manjar branco estudados aumentou ao longo do armazenamento e o manjar T2 apresentou menor firmeza a partir de 14 dias de armazenamento. No entanto, essa diferença não foi observada durante a análise sensorial do manjar branco para nenhum dos tratamentos. De fato, a avaliação sensorial não detectou diferenças evidentes da adição de culturas isoladas ou em co-cultura de bifidobacteria e L. paracasei nas características sensoriais. Não foi observada nenhuma diferença significativa entre os tratamentos (p = 0,06) durante o período de vida-de-prateleira de 21 dias (p = 0,24). Entretanto, foi observada uma tendência de melhores notas para os manjares adicionados de microrganismos probióticos, comparados ao manjar branco controle e uma tendência de redução das notas quando ambos os microrganismos foram adicionados. A adição de Lactobacillus paracasei e Bifidobacterium longum ao manjar branco resultou em um produto potencialmente probiótico e com excelentes atributos sensoriais, particularmente quando a adição das culturas foi realizada individualmente. / The ingestion of foods that promote health in addition to providing basic nutrition, like foods supplemented with probiotics cultures, which may exert a positive effect on the gut indigenous microbiota is becoming increasingly important. The development of a non-fermented dairy dessert which allows the supplementation with probiotics, like coconut flan, appears to be a good option, due to the growing interest that food companies and the scientific community have demonstrated in new probiotic products. The present research aimed to study the viability of Lactobacillus paracasei subsp. paracasei and Bifidobacterium longum, added as single cultures or in co-culture, in coconut flan supplemented with these potentially probiotic cultures and to evaluate the behavior of the probiotics and the features of the product during refrigerated storage. Coconut flans were produced with no addition of cultures (T1 - control), or supplemented with Bifidobacterium longum (T2), Lactobacillus paracasei subsp. paracasei (T3) and B. longum + L. paracasei (T4). The products were sensory evaluated (after 7, 14 and 21 days of storage, at 4±1°C, employing a structured hedonic scales, with 24 untrained panelists at each period) and monitored microbiologically for the viability of the probiotics and the counts of contaminants (coliforms, Escherichia coli, Staphylococcus spp., yeasts and moulds), as well as for their instrumental texture profile and their physicochemical features (pH, moisture) through the 28 days of storage at 4±1ºC. During storage of the products for 28 days, the mean populations of L. paracasei increased from 6.6 to 8.6 log CFU/g and from 6.4 to 7.3 log CFU/g, for T3 and T4, respectively. B. longum presented populations always between 7.3 and 7.5 log CFU/g, and between 7.1 and 7.5 log CFU/g for T2 and T4, respectively. Coconut flan T3 underwent higher decreases in pH values (P<0,05). On the other hand, moisture showed no significant differences (P>0,05) between trials and during the shelf life period. The firmness of all coconut flans studied increased during storage, and coconut flan T2 presented lower firmness after 14 days of storage. Nevertheless, this difference was not detected during the sensory evaluation of coconut flans. In fact, the sensory analyses did not shown marked differences from the addition of probiotic cultures of bifidobacteria and L. paracasei as single cultures or in co-culture, on sensory features. No significant differences between trials (P=0,06) and during the 21 days of shelf life period (P=0,24) were detected. However, a tendency of better scores for the coconut flans supplemented with the probiotic microorganisms, compared with the control product, and a tendency of reduction of scores when both microorganisms were presented in the coconut flan formulation were observed. The supplementation of coconut flans with Lactobacillus paracasei and Bifidobacterium longum resulted in great potential as a functional food, and with high sensory acceptability, particularly when single cultures were employed.
53

Produção de bacteriocina por Bifidobacterium lactis a partir de soro de leite / Production of bacteriocin by Bifidobacterium lactis from whey

Eduardo Marcos Balciunas 13 September 2013 (has links)
Objetivou-se a produção de bacteriocina de Bifidobacterium animalis subsp. lactis, comparando-se os meios de cultivo sintéticos BSM (Bifidus Selective Medium) e MRS (Man Rogosa and Sharpe) com o meio de cultivo natural (soro de leite). Inicialmente, foram determinadas curvas de crescimento e de pós-acidificação, consumo de glicose, lactose e produção de bacteriocina de B.lactis através de processos fermentativos utilizando os meios de cultivo BSM, MRS e soro de leite (SL). Os microrganismos indicadores utilizados no teste de sensibilidade à bacteriocina produzida por B. lactis foram Lactobacillus sakei, Escherichia coli e Listeria monocytogenes. Considerando a cepa B. lactis uma espécie de bactéria aerotolerante, foi realizado, em meio de cultura BSM, estudo prévio avaliando o seu crescimento, com a variação da agitação (25, 50 e 100 rpm) e com tempo de cultivo de 30 h, a 37°C de temperatura. Os melhores resultados de crescimento celular (9,4 log UFC/mL) foram obtidos na agitação de 50 rpm. Determinada a melhor condição de agitação (50 rpm) e temperatura (37°C), foi realizado, em soro de leite, estudo de crescimento, acidificação e consumo de lactose, variando a concentração de sólidos totais dissolvidos (5, 10, 15, 20 e 25% p/v), para se estabelecer a concentração de soro de leite ideal para os estudos de suplementação. A maior quantidade de biomassa produzida, aliada à menor pós-acidificação, foi encontrada em soro de leite a 10% (p/v) de sólidos totais, no qual o microrganismo apresentou, ao final do cultivo (30 horas), contagem de 9,13 log UFC/mL e valor de pH 4,29, respectivamente. Também se verificou a influência dos meios de cultivo no crescimento e na produção de bacteriocina de B. lactis em agitador rotativo (shaker), que consistiu na análise comparativa do efeito da suplementação de 1% dos seguintes ingredientes: extrato de levedura (EL), inulina (I), L-cisteína (CI) e Tween 80 (T80). As melhores condições de cultivo encontradas para a maior produção de biomassa e bacteriocina foram obtidas no soro de leite, à concentração de 10% (p/v) suplementado com 1% de extrato de levedura (9,9 log UFC/mL e 200 UA/mL). Na etapa final do trabalho, estas condições foram testadas em fermentador de bancada, quando foi observado que o crescimento de Bifidobacterium lactis foi 10% maior em relação ao agitador rotativo. Quanto à atividade da bacteriocina produzida em fermentador de bancada, não houve diferença em relação ao agitador rotativo (200 UA/mL). Esta diferença no crescimento pode ser devido as melhores condições de anaerobiose oferecidas em fermentador de bancada, no qual houve a injeção de nitrogênio no meio de cultivo, sendo que, no agitador rotativo, a condição de anaerobiose foi gerada por um agente externo ao meio (uso de jarras de anaerobiose). Através do presente trabalho, pode-se concluir que a produção de bacteriocina por B. lactis é viável e apresenta resultados promissores quando utilizada a combinação soro de leite adicionado de extrato de levedura, o qual apresentou atividade antimicrobiana contra a cepa Listeria monocytogenes. A otimização do processo em fermentador de bancada demonstrou-se interessante quanto à produção de bacteriocina em nível industrial. / The objective was the production of bacteriocins by Bifidobacterium animalis subsp. lactis, comparing the synthetic culture medium BSM (Bifidus Selective Medium) and MRS (Man Rogosa and Sharpe) with the natural culture medium (whey). Initially, growth and post-acidification curves were determined, consumption of glucose, lactose and B. lactis bacteriocin production by fermentation processes using culture media BSM, MRS and milk whey (SL).The indicator organisms used in the test sensitivity to bacteriocin produced by B. lactis were Lactobacillus sakei, Escherichia coli and Listeria monocytogenes. Given the strain B. lactis one aerotolerant species of bacteria, it was conducted in culture medium BSM, a preliminary study assessing the growth, by varying the agitation (25, 50, and 100 rpm) with cultivation time of 30h at 37°C temperature. The best results of cell growth (9.4 log CFU / mL) were obtained at 50 rpm agitation. After the best condition of agitation (50 rpm) and temperature (37°C) determination, it was performed on whey, a study of growth, acidification and consumption of lactose, varying the concentration of total dissolved solids (5, 10, 15, 20 and 25% w/v), to settle the best concentration of whey for studies of supplementation. The highest amount of biomass produced, combined with the lowest post acidification was found in whey at 10% (w/v) of total solids, wherein the microorganism presented at the end of culture (30 hours) a counting of 9.13 log CFU/mL and pH 4.29, respectively. It was also verified the influence from the culture media on B. lactis growth and production of bacteriocin on a rotary shaker (shaker), which was the comparative analysis from the effect of supplementation by 1% of the following ingredients: yeast extract (EL), inulin (I), L-cysteine (IC) and Tween 80 (T80). The best growing conditions found for higher biomass and bacteriocin production were obtained from the whey concentration of 10% (w/v) supplemented with 1% yeast extract (9.9 log CFU/ml to 200 AU/mL). In the final stage of the work, these conditions were tested in bench fermentor, where it was observed that the growth of Bifidobacterium lactis was 10% higher than in the rotary shaker. Regarding the activity of bacteriocin produced in fermenter bench, there was no difference in the rotary shaker (200 AU / mL). This difference in growth may be due to the better anaerobic conditions offered in bench fermentor, which was the injection of nitrogen into the medium, and in a rotary shaker, the anaerobic condition was generated by an external agent to the medium (use of anaerobic jars). Through this study, it can be concluded that bacteriocin production by B. lactis is achievable and shows promising results when used the combination whey added yeast extract, which showed antimicrobial activity against the strain Listeria monocytogenes. The optimization process bench fermentor has been shown interesting as bacteriocin production at industrial level.
54

Desenvolvimento e caracterização de chocolate meio amargo contendo micro-organismos probióticos na forma livre e encapsulada / Development and characterization of semisweet chocolate containing probiotic microorganisms in free form and encapsulated

Marluci Palazzolli da Silva 12 December 2016 (has links)
O objetivo desse trabalho foi avaliar o chocolate meio amargo, uma matriz alimentícia pouco explorada no mercado de produtos probióticos, porém muito atrativa para os consumidores, para a adição de Lactobacillus acidophilus (LA3) e Bifidobacterium animalis subsp. lactis (BLC1) na forma livre ou encapsulada. Na primeira etapa do trabalho, micropartículas sólidas lipídicas (MSL) foram produzidas por spray chilling ou recobertas por interação eletrostática dos polímeros (PLRIE), sendo em seguida caracterizadas para verificar se os métodos de encapsulação foram eficientes para a proteção dos probióticos. Na segunda etapa, foram elaboradas e caracterizadas amostras de chocolate meio amargo adicionadas dos probióticos nas formas livre ou encapsulada por spray chilling. Além disso, os produtos foram avaliados sensorialmente por 100 provadores para verificar sua aceitação sensorial. Em relação ao ensaio de sobrevivência dos micro-organismos aos fluidos gastrointestinais simulados, as contagens das populações de LA3 e BLC1 livres, antes de serem aplicados em chocolate, reduziram respectivamente 2,5 e 4 log UFC/g. Após a aplicação dos probióticos em chocolate meio amargo, LA3 e BLC1 livres apresentaram reduções em suas populações de 0,25 e 0,30 log UFC/g, respectivamente, sendo que ambas as contagens das populações encapsuladas apresentaram um decréscimo de aproximadamente 0,50 e 1,10 log UFC/g. Após 120 dias de estocagem do chocolate a 25 °C, as contagens das populações de LA3 e BLC1, na forma livre, apresentaram reduções de 1,40 e 0,70 log UFC/g, enquanto que para as populações dos micro-organismos encapsulados, as contagens foram abaixo do limite de detecção do método. As amostras de chocolate apresentaram aw abaixo de 0,6, pH entre 5,77 - 5,87, teor de gordura e de fenólicos, respectivamente de 34% e 15 mg de ácido gálico equivalente/g de chocolate. Em relação à textura, foi verificado que todas as amostras de chocolate apresentaram um ligeiro incremento da dureza após o período de armazenamento. Por meio do microscópio eletrônico de varredura (MEV) foi visualizada a presença de cristais de gordura, fat bloom, após 120 dias de estocagem em todas amostras de chocolate, o que pode ser relacionado também com o aumento do índice de brancura. Na avaliação sensorial, todas as amostras apresentaram nota de aceitação acima de 7,1, na escala hedônica de 9 pontos. Além disso, todos os produtos apresentaram pelo menos 75% de intenção de compra. Portanto, demonstrou-se que o chocolate meio amargo é uma ótima matriz alimentícia devido a sua composição e características físico-químicas para incorporação de probióticos, não sendo necessária a refrigeração do produto para manter a população dos probióticos durante esse período de estocagem, somando-se ao fato do produto não ter sido alterado sensorialmente após a adição dos micro-organismos probióticos. / The aim of this study was to evaluate the semisweet chocolate, a food matrix little explored in the market of probiotic products, however, very attractive for consumers, for the addition of Lactobacillus acidophilus (LA3) and Bifidobacterium animalis subsp. lactis (BLC1) in free form or encapsulated. In the first stage of the work, solid lipid microparticles (SLM) were produced by spray chilling or covered by electrostatic interaction of polymers (LPCEI), and then characterized to verify if encapsulation methods were efficient for the protection of probiotic cells. In the second stage, semisweet chocolate samples added of probiotics in free form or encapsulated by spray chilling were prepared and characterized. Moreover, the products were evaluated sensorially by 100 panelists to verify their global acceptance.With respect to the test of microorganism survival to simulated gastrointestinal fluids, the counts of LA3 and BLC1 in free form, before being added to chocolate, have reduced respectively 2,5 and 4 log CFU/g. After the application of probiotics in semisweet chocolate, LA3 and BLC1 free have shown reductions in their populations of 0,25 and 0,30 log CFU/g, respectively, and both counts of encapsulated populations have decreased approximately 0,50 and 1,10 log CFU/g. After 120 days of storage of the chocolate at 25 ° C, the counts of LA3 and BLC1 in free form showed reductions of 1,40 and 0,70 log CFU/g, while in the populations of encapsulated microorganisms, the counts were below method detection limit. The samples of chocolate presented aw below 0,6, pH between 5,77 to 5,87, fat and phenolic, respectively, 34% and 15 mg gallic acid equivalent/g of chocolate. Concerning the texture, it has been found that all samples chocolate showed a slight increase in the hardness after storage. Scanning electron microscope (SEM) has been used to visualize the presence of fat crystals and all samples of chocolate presented fat bloom after 120 days of storage, which can also be correlated with the increase in whiteness index. Regarding the sensory evaluation, all samples have shown acceptance mark above 7,1, on a hedonic scale of 9 points. In addition, all products have had at least 75% of purchase intent. Therefore, it has been demonstrated that the semisweet chocolate is an excellent food matrix due to its composition and physical-chemical properties for incorporation of probiotics, adding to the fact that is not necessary to cool the product to maintain the bacterial population during this storage period, as well as it has not been altered sensory after the addition of probiotics microorganisms.
55

Iogurte caprino probiótico em pó: estudo do processo de secagem, da caracterização do pó e da viabilidade do probiótico / Goat milk yogurt powder with probiotics: study of the drying process, the powder characterization and probiotic viability

Adja Cristina Lira de Medeiros 25 February 2013 (has links)
Os objetivos do estudo foram elaborar iogurtes com a cultura tradicional e a cultura probiótica de Bifidobacterium animalis subsp. lactis, desidratar os produtos em spray dryer utilizando maltodextrina como carreador e caracterizar os pós obtidos, bem como determinar a resistência dos probióticos ao processo de atomização. O presente estudo avaliou três temperaturas de entrada do ar de secagem (130, 150 e 170°C) em iogurtes com duas diferentes concentrações de maltodextrina (10 e 20%), totalizando 6 tratamentos: T1 (10%malto/130°C), T2 (20%malto/130°C), T3 (10%malto/150°C), T4 (20%malto/150°C), T5 (10%malto/170°C) e T6 (20%malto/170°C). A secagem do iogurte foi realizada em spray dryer piloto e a enumeração das células viáveis de Bifidobacterium animalis subsp. lactis foi realizada através de plaqueamento em profundidade. Os pós apresentaram baixos valores de umidade e elevada higroscopicidade. A atividade de água (Aw) dos pós variou de 0,09 a 0,19 e aumentou após 30 dias de armazenamento, comprovando o caráter higroscópico dos pós obtidos. Verificou-se que após a desidratação dos iogurtes, apesar deles apresentarem contagens inferiores que os produtos integrais, ainda apresentaram contagens acima de 106 UFC/g, ou seja, ainda estavam dentro do limite estabelecido pela legislação para um produto ser considerado probiótico. Os tratamentos que passaram por maiores temperaturas durante o processamento de secagem (T5 e T6) foram os que tiveram maiores perdas de micro-organismos probióticos, sugerindo que as altas temperaturas exerceram forte influência na viabilidade dos probióticos. O T1 obteve maiores contagens do micro-organismo analisado, com contagens acima de 106 UFC/g, com até 60 dias de armazenamento, indicando ser o melhor tratamento entre os estudados, em relação à obtenção de um iogurte caprino probiótico em pó com maior período de vida de prateleira. De maneira geral, conclui-se que o processo de atomização possibilitou a obtenção de iogurte de leite de cabra em pó estável do ponto de vista microbiológico. Além disso, obteve-se um produto que pode ser uma alternativa para incrementar o consumo de leite de cabra, bem como o de probióticos. / The aim of this study was to develop yogurts with the traditional culture and Bifidobacterium animalis subsp. lactis probiotic culture, dehydrate products in spray drying using maltodextrin as a carrier and characterize the powders, as well as determining the resistance of probiotics to atomization process. The present study evaluated three different inlet air temperatures of spray dryer (130, 150 and 170°C) in yoghurts with two different maltodextrin concentrations (10 and 20%), totaling six treatments: T1 (10%malto/130°C), T2 (20%malto/130°C), T3 (10%malto/150°C), T4 (20%malto/150°C), T5 (10%malto/170°C) e T6 (20%malto/170°C). The yogurt drying was performed in a pilot spray dryer and the viable cells of Bifidobacterium animalis subsp. lactis enumeration was performed by pour plate. The powders showed low levels of humidity and high hygroscopicity. The water activity (Aw) of the powders ranged from 0.09 to 0.19 and increased after 30 days of storage, showing the hygroscopic powders character. It was found that after yogurt dehydration, despite their counts were less than integral products, still had counts above 106 CFU/g, therefore were still within regulation limits for a product to be considered as probiotic. The treatments that have undergone higher temperatures during the drying process (T5 and T6) were those who had higher losses of probiotic microorganisms, suggesting that high temperatures had a strong influence on the viability of probiotics. The T1 (130°C/10%) obtained higher counts of the microorganism analyzed, with counts above 106 CFU/g, during 60 days of storage, indicating that is the best treatment among those studied in relation to obtaining a goat probiotic yoghurt powder with longer shelf life. In general, it is concluded that the atomization process allows the obtention of stable goat milk yogurt powder, in a microbiological point of view. Furthermore, it was obtained a product that can be an alternative for increasing the consumption of goat milk as well as probiotics.
56

Effect of barley [beta]-glucans with different molecular weight on the proliferation and metabolism of bifidobacteria.

January 2007 (has links)
Lee, Ying. / On t.p. "beta" appears as the Greek letter. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 171-196). / Abstracts in English and Chinese. / Thesis/Assessment Committee --- p.i / Acknowledgement --- p.ii / Abstract --- p.iii / 摘要 --- p.v / List of Tables --- p.vii / List of Figures --- p.x / List of Abbreviations --- p.xvii / Content --- p.xviii / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Probiotics and Prebiotics --- p.1 / Chapter 1.1.1 --- Definitions --- p.1 / Chapter 1.1.2 --- Previous studies --- p.2 / Chapter 1.1.3 --- Properties of enhanced prebiotics --- p.6 / Chapter 1.1.4 --- Synbiotics --- p.7 / Chapter 1.2 --- Colonic fermentation --- p.10 / Chapter 1.2.1 --- Major substrates and metabolites of colonic fermentation --- p.10 / Chapter 1.2.2 --- Health-related effects of Short-Chain Fatty Acids (SCFAs) --- p.12 / Chapter 1.3 --- Bifidogenic effect --- p.14 / Chapter 1.3.1 --- Definition of bifidogenic factor and its health benefits --- p.14 / Chapter 1.3.2 --- Carbohydrate metabolism by related enzymes of bifidobacteria --- p.16 / Chapter 1.3.3 --- Previous studies on bifidogenic effects of carbohydrates --- p.18 / Chapter 1.4 --- Barley β-glucan --- p.18 / Chapter 1.4.1 --- Cereal fibres as prebiotics --- p.18 / Chapter 1.4.2 --- Chemical and physical properties and related health impacts of barley β-glucan --- p.19 / Chapter 1.4.3 --- Impacts on intestinal microecology --- p.21 / Chapter 1.4.4 --- Previous studies on bifidogenic effects of barley β-glucan --- p.21 / Chapter 1.5 --- Methodology for evaluating prebiotic and bifidogenic effect --- p.22 / Chapter 1.5.1 --- In vivo animal models --- p.23 / Chapter 1.5.2 --- Human clinical study --- p.23 / Chapter 1.5.3 --- In vitro fermentation study --- p.24 / Chapter 1.5.3.1 --- Pure culture --- p.24 / Chapter 1.5.3.2 --- Mixed culture bacterial fermenters --- p.25 / Chapter 1.5.3.3 --- Continuous culture systems as in vitro gut models --- p.25 / Chapter 1.5.4 --- Advanced molecular techniques in quantifying intestinal bacteria --- p.26 / Chapter 1.6 --- Factors affecting bifidogenic effect --- p.30 / Chapter 1.6.1 --- Molecular weight --- p.30 / Chapter 1.6.2 --- Species difference --- p.31 / Chapter 1.7 --- Enzymatic activities involved in fermentation of β-glucan --- p.32 / Chapter 1.7.1 --- "Endo-1,3-1,4-(3-glucanase (Lichenase)" --- p.32 / Chapter 1.7.2 --- "Endo-l,4-β-Glucanase (Cellulase)" --- p.33 / Chapter 1.7.3 --- Enzymatic assays --- p.33 / Chapter 1.8 --- Project objectives --- p.36 / Chapter Chapter 2. --- Materials and Methods --- p.37 / Chapter 2.1 --- Materials --- p.37 / Chapter 2.1.1 --- "Trehalose, chitin and lactulose" --- p.37 / Chapter 2.1.2 --- Barley β-glucan --- p.37 / Chapter 2.1.3 --- Pure Bifidobacterium species of human origin --- p.39 / Chapter 2.2 --- Static batch culture fermentation using fecal inoculums --- p.39 / Chapter 2.2.1 --- Substrate preparation --- p.39 / Chapter 2.2.2 --- Human fecal inoculum preparation --- p.41 / Chapter 2.2.3 --- Inoculation of human fecal inoculums --- p.41 / Chapter 2.3 --- Static batch culture fermentation using pure culture of bifidobacteria --- p.42 / Chapter 2.3.1 --- Substrate preparation --- p.42 / Chapter 2.3.2 --- Cultivation of pure bifidobacterium cultures --- p.43 / Chapter 2.3.3 --- Inoculation of bifidobacterium culture --- p.44 / Chapter 2.3.4 --- Growth curve of Bifidobacterium species --- p.44 / Chapter 2.4 --- Dry matter and organic matter disappearance in batch fermentation --- p.47 / Chapter 2.5 --- Gas chromatographic (GC) determination of short-chain fatty acids (SCFAs) --- p.48 / Chapter 2.6 --- MTT assay --- p.51 / Chapter 2.7 --- Microbial identification and enumeration --- p.53 / Chapter 2.7.1 --- Fluorescent in situ hybridization --- p.53 / Chapter 2.7.1.1 --- Oligonucleotide probes for fluorescent in situ hybridization --- p.53 / Chapter 2.7.1.2 --- Cell fixation --- p.54 / Chapter 2.7.1.3 --- In situ hybridization --- p.55 / Chapter 2.7.1.4 --- Automated image analysis --- p.55 / Chapter 2.7.1.5 --- Quantification of bacteria --- p.57 / Chapter 2.7.2 --- Optical Density (OD) measurement --- p.58 / Chapter 2.7.3 --- Direct microscopic count --- p.59 / Chapter 2.8 --- Enzyme assays --- p.60 / Chapter 2.8.1 --- Enzyme extraction --- p.60 / Chapter 2.8.2 --- "Endo-1, 3:1, 4-β-glucanase (Lichenase)" --- p.61 / Chapter 2.8.2.1 --- Principle --- p.61 / Chapter 2.8.2.2 --- Preparation of substrate and assay solutions --- p.63 / Chapter 2.8.2.3 --- Enzyme assay procedures --- p.64 / Chapter 2.8.3 --- "Endo-l,4-β-Glucanase (Cellulase)" --- p.65 / Chapter 2.8.3.1 --- Principle --- p.65 / Chapter 2.8.3.2 --- Dissolution of substrate and preparation of assay solutions --- p.65 / Chapter 2.8.3.3 --- Enzyme assay procedures --- p.66 / Chapter 2.8.4 --- API@ ZYM kit --- p.67 / Chapter 2.8.4.1 --- Principle --- p.67 / Chapter 2.8.4.2 --- Specimen preparation --- p.68 / Chapter 2.8.4.3 --- "Preparation, inoculation and reading of the strips" --- p.70 / Chapter 2.9 --- Statistical analysis --- p.71 / Chapter Chapter 3 --- Results and Discussions --- p.72 / Chapter 3.1 --- Growth curves of Bifidobacterium species --- p.72 / Chapter 3.2 --- Batch in vitro fermentation using human fecal inoculum --- p.79 / Chapter 3.2.1 --- Dry matter and organic matter disappearance --- p.79 / Chapter 3.2.2 --- Colonic bacterial profile evaluated by FISH with CellC software --- p.81 / Chapter 3.2.2.1 --- Total colonic bacteria --- p.81 / Chapter 3.2.2.2 --- Bifidobacterial growth --- p.82 / Chapter 3.2.3 --- SCFA production --- p.86 / Chapter 3.2.3.1 --- Acetate --- p.88 / Chapter 3.2.3.2 --- Propionate --- p.89 / Chapter 3.2.3.3 --- Butyrate --- p.89 / Chapter 3.2.3.4 --- Total SCFA production --- p.90 / Chapter 3.2.3.5 --- Molar ratio of SCFAs --- p.92 / Chapter 3.3 --- In vitro fermentation of barley β-glucans with different molecular weight using pure culture of Bifidobacterium species --- p.95 / Chapter 3.3.1 --- Dry matter and organic matter disappearance --- p.96 / Chapter 3.3.2 --- Evaluation of bifidobacterial growth by optical density (OD) --- p.100 / Chapter 3.3.3 --- Time course study of SCFAs production --- p.109 / Chapter 3.3.3.1 --- "Total and individual SCFAs (Acetate, Propionate and Butyrate) production" --- p.109 / Chapter 3.3.4 --- Correlation between various parameters related to fermentation --- p.124 / Chapter 3.4 --- Enzymatic activities in 2 selected Bifidobacterium species during fermentation --- p.125 / Chapter 3.4.1 --- Dry matter and organic matter disappearance --- p.126 / Chapter 3.4.2 --- Bifidobacterial growth evaluated by direct microscopic count --- p.128 / Chapter 3.4.3 --- Time course study of SCFAs production --- p.131 / Chapter 3.4.3.1 --- "Total and individual SCFAs production (Acetate, Propionate and Butyrate)" --- p.131 / Chapter 3.4.3.2 --- MTT assay --- p.137 / Chapter 3.4.3.2.1 --- Effect of metabolites in the fermentation medium on the proliferation ofSW620 --- p.137 / Chapter 3.4.3.2.2 --- Effect of metabolites in the fermentation medium on the proliferation of Caco-2 --- p.145 / Chapter 3.4.4 --- Enzyme assays using commercial kits --- p.153 / Chapter 3.4.4.1 --- API @ZYM assay --- p.153 / Chapter 3.4.4.2 --- Efficiency of intra-cellular enzyme extraction using labiase --- p.156 / Chapter 3.4.5 --- Time course enzyme assays --- p.157 / Chapter 3.4.5.1 --- Lichenase activity assay --- p.157 / Chapter 3.4.5.2 --- Cellulase activity assay --- p.160 / Chapter Chapter 4. --- Conclusions and Future work --- p.168 / References --- p.171
57

Desenvolvimento de manjar branco potencialmente probiótico / Development of potential probiotic coconut flan

Corrêa, Sabrina Barros de Mattos 14 July 2006 (has links)
A ingestão de alimentos que, além de fornecerem a nutrição, promovem a saúde, como os alimentos funcionais adicionados de probióticos, que auxiliam no equilíbrio da microbiota intestinal, é de vital importância. Em virtude do crescente interesse da indústria e da comunidade científica por novos produtos probióticos, o desenvolvimento de uma sobremesa láctea que permita a adição de probióticos, como o manjar branco, é promissor. O presente trabalho visou desenvolver um manjar branco com a adição dos microrganismos potencialmente probióticos, Lactobacillus paracasei subsp. paracasei e/ou Bifidobacterium longum, adicionados isoladamente e em co-cultura, e avaliar o comportamento dos probióticos e as características do produto ao longo do seu armazenamento refrigerado. Quatro tratamentos de manjar branco foram produzidos (com 3 repetições cada): T1 (controle - sem a adição de culturas), T2 (com Bifidobacterium longum), T3 (com Lactobacillus paracasei) e T4 (com B. longum + L. paracasei). O produto foi avaliado sensorialmente (após 7, 14 e 21 dias de armazenamento a 4±1°C, através de escala hedônica estruturada, com 24 provadores não treinados em cada período) e, durante o seu armazenamento por até 28 dias, microbiologicamente quanto à viabilidade dos probióticos e à contagem de contaminantes (coliformes, Escherichia coli, Staphylococcus spp. e bolores e leveduras) e quanto às suas características físico químicas (umidade, pH) e de textura instrumental. Durante o armazenamento dos produtos por 28 dias, as populações médias de L. paracasei aumentaram de 6,6 para 8,6 log UFC/g e de 6,4 para 7,3 log UFC/g, para T3 e T4, respectivamente. B. longum revelou populações sempre entre 7,3 e 7,5 log UFC/g e entre 7,1 e 7,5 log UFC/g para T2 e T4, respectivamente. O manjar T3 resultou em uma redução mais acentuada do pH (p<0,05), mas a umidade não foi significativamente distinta para os diferentes produtos (p>0,05). A firmeza de todos os tratamentos de manjar branco estudados aumentou ao longo do armazenamento e o manjar T2 apresentou menor firmeza a partir de 14 dias de armazenamento. No entanto, essa diferença não foi observada durante a análise sensorial do manjar branco para nenhum dos tratamentos. De fato, a avaliação sensorial não detectou diferenças evidentes da adição de culturas isoladas ou em co-cultura de bifidobacteria e L. paracasei nas características sensoriais. Não foi observada nenhuma diferença significativa entre os tratamentos (p = 0,06) durante o período de vida-de-prateleira de 21 dias (p = 0,24). Entretanto, foi observada uma tendência de melhores notas para os manjares adicionados de microrganismos probióticos, comparados ao manjar branco controle e uma tendência de redução das notas quando ambos os microrganismos foram adicionados. A adição de Lactobacillus paracasei e Bifidobacterium longum ao manjar branco resultou em um produto potencialmente probiótico e com excelentes atributos sensoriais, particularmente quando a adição das culturas foi realizada individualmente. / The ingestion of foods that promote health in addition to providing basic nutrition, like foods supplemented with probiotics cultures, which may exert a positive effect on the gut indigenous microbiota is becoming increasingly important. The development of a non-fermented dairy dessert which allows the supplementation with probiotics, like coconut flan, appears to be a good option, due to the growing interest that food companies and the scientific community have demonstrated in new probiotic products. The present research aimed to study the viability of Lactobacillus paracasei subsp. paracasei and Bifidobacterium longum, added as single cultures or in co-culture, in coconut flan supplemented with these potentially probiotic cultures and to evaluate the behavior of the probiotics and the features of the product during refrigerated storage. Coconut flans were produced with no addition of cultures (T1 - control), or supplemented with Bifidobacterium longum (T2), Lactobacillus paracasei subsp. paracasei (T3) and B. longum + L. paracasei (T4). The products were sensory evaluated (after 7, 14 and 21 days of storage, at 4±1°C, employing a structured hedonic scales, with 24 untrained panelists at each period) and monitored microbiologically for the viability of the probiotics and the counts of contaminants (coliforms, Escherichia coli, Staphylococcus spp., yeasts and moulds), as well as for their instrumental texture profile and their physicochemical features (pH, moisture) through the 28 days of storage at 4±1ºC. During storage of the products for 28 days, the mean populations of L. paracasei increased from 6.6 to 8.6 log CFU/g and from 6.4 to 7.3 log CFU/g, for T3 and T4, respectively. B. longum presented populations always between 7.3 and 7.5 log CFU/g, and between 7.1 and 7.5 log CFU/g for T2 and T4, respectively. Coconut flan T3 underwent higher decreases in pH values (P<0,05). On the other hand, moisture showed no significant differences (P>0,05) between trials and during the shelf life period. The firmness of all coconut flans studied increased during storage, and coconut flan T2 presented lower firmness after 14 days of storage. Nevertheless, this difference was not detected during the sensory evaluation of coconut flans. In fact, the sensory analyses did not shown marked differences from the addition of probiotic cultures of bifidobacteria and L. paracasei as single cultures or in co-culture, on sensory features. No significant differences between trials (P=0,06) and during the 21 days of shelf life period (P=0,24) were detected. However, a tendency of better scores for the coconut flans supplemented with the probiotic microorganisms, compared with the control product, and a tendency of reduction of scores when both microorganisms were presented in the coconut flan formulation were observed. The supplementation of coconut flans with Lactobacillus paracasei and Bifidobacterium longum resulted in great potential as a functional food, and with high sensory acceptability, particularly when single cultures were employed.
58

Viabilidade de Bifidobacterium animalis subsp. lactis HN019 em fórmulas infantis probióticas durante o armazenamento a 4 ºC / Viability of Bifidobacterium animalis ssp. lactis HN019 in probiotic infant formulas

Sousa, Ana Lucia Orlandini Pilleggi de 19 May 2011 (has links)
O objetivo deste trabalho foi estudar a viabilidade de Bifidobacterium animalis subsp. lactis HN019 em fórmulas infantis fermentadas ou não, probióticas durante armazenamento a 4°C. Três matrizes lácteas e três não lácteas (a base de soja) foram utilizadas para a elaboração de produtos fermentados ou não fermentados usando Bifidobacterium animalis subsp. lactis HN019, resultando em doze diferentes fórmulas probióticas para lactentes. O perfil de acidificação foi determinado a 42°C até pH 4,7. Determinações físico-químicas (sólidos totais, proteína, gordura, cinzas, carboidratos, calorias, densidade e pH) foram realizadas e foram focadas as contagens de bactérias viáveis durante o armazenamento refrigerado. A caracterização química dos produtos lácteos e a não lácteos apresentou resultados diferentes, à exceção FSL2, todos estavam de acordo com Codex Alimentarius. O perfil de acidificação de Bifidobacterium animalis subsp. lactis HN019 diferiu conforme a matriz. Durante o armazenamento dos produtos a 4°C, a contagem de bactérias viáveis de acordo com o preconizado, bem como a pós-acidificação, estando em conformidade com as recomendações da legislação brasileira. Processo (fermentação ou adição) e tipo de matriz (lácteos e não lácteos) influenciaram a pós-acidificação e a viabilidade de Bifidobacterium animalis subsp. lactis HN019. As fórmulas para lactentes podem ser considerados bons veículos de Bifidobacterium animalis subsp. lactis HN019. / This study proposed to study infant formulas as vehicles for Bifidobacterium animalis ssp.lactis HNOI9. Three dairy and three non-dairy matrices were employed for the preparation of fermented or unfermented products using Bifidobacterium animalis ssp. lactis HN019 resulting in twelve different probiotic infant formulas. Acidification profile of the probiotic was determined at 42°C until pH 4.7. Physicochemical determination (total solids, protein, fat, ash, carbohydrates and calories, density and pH) was conducted, and counts viable bacteria (in dairy and non dairy infant formulas fermented and unfermented) during cold storage was focused on. The chemical characterization of the dairy and non-dairy matrix showed different results, the exception FSL2, all were in accordance to the Codex Alimentarius. The acidification profile of B. animalis ssp. lactis HN019 differed according to the matrix. During storage of products at 4°C counts of viable bacteria were stable as well as post-acidification, and were in accordance with the recommendations of the Brazilian legislation. Process (fermentation or addition) and matrix type (dairy and non-dairy) influenced post-acidification and viability of B. animalis ssp. lactis BN019 . Infant formulas could be considered good vehicles for Bifidobacterium animalis ssp. lactis HN019.
59

Einfluss von Synbiotika auf die intestinale Mikrobiota gesunder Neugeborener / Effect of starter formula with synbiotics on the intestinal microbiota of healthy newborn infants

Junick, Jana January 2013 (has links)
Hintergrund: Gestillte Kinder haben im Vergleich zu nicht gestillten Kindern eine geringere Inzidenz von gastrointestinalen Infektionen und atopischen Erkrankungen. Man geht davon aus, dass der gesundheitsfördernde Effekt der Muttermilch teilweise über die intestinale Mikrobiota vermittelt wird. Diese ist in Stillkindern durch eine geringe Diversität und einen hohen Anteil an Bifidobakterien charakterisiert. Neueste Ansätze in der Weiterentwicklung industriell hergestellter Säuglingsnahrung zielen darauf ab, eine intestinale Mikrobiota zu fördern, die der von gestillten Kindern ähnelt. Die Supplementation von Säuglingsnahrung mit Probiotika (lebende Mikroorganismen) oder Präbiotika (unverdauliche Kohlenhydrate, die als Energiesubstrat für probiotische Bakterien dienen) könnte die bifidogene und antipathogene, aber auch immunmodulierende Wirkung der Muttermilch nachahmen. Aufgrund unterschiedlicher Interaktionen mit der Darmmikrobiota und dem Immunsystem fokussiert man mit der gleichzeitigen Gabe von Pro- und Präbiotika (Synbiotika) eine synergistische Wirkung an. Zielstellung und Studiendesign: In einer randomisiert-kontrollierten, klinischen Studie wurde untersucht, ob sich in den ersten drei Lebensmonaten von gesunden und termingerecht geborenen Kindern mit einer Synbiotikum-haltigen Säuglingsnahrung eine intestinale Mikrobiota etabliert, die der von gestillten Kindern gleicht. Das Synbiotikum setzte sich aus Bifidobacterium animalis ssp. lactis CNCM I 3446 (ältere Bezeichnung B. lactis BB-12) und Kuhmilcholigosacchariden zusammen. Die Studie umfasste zwei Gruppen von Kindern, die eine Säuglingsnahrung mit (SYN-Gruppe, n=21) oder ohne Supplement (KON-Gruppe, n=18) erhielten. Gestillte Kinder dienten als Referenz (REF-Gruppe, n=23). Um die Diversität der Bifidobakterien auf Speziesebene umfassend zu charakterisieren, wurden quantitative Real-Time PCR (qPCR)-Verfahren, basierend auf dem single-copy groEL als phylogenetisches Zielgen, zur spezifischen Quantifizierung von zwölf Bifidobakterienspezies in humanen Fäzes entwickelt und validiert. Ergebnisse: Die supplementierte Säuglingsnahrung war gut verträglich und unterstützte eine gesunde Entwicklung; vergleichbare anthropometrische Daten von SYN- und REF-Gruppe. Das Synbiotikum stimulierte selektiv das Wachstum von Laktobazillen und Bifidobakterien. Die Zellzahl für Laktobazillen der SYN-Gruppe war zur REF-Gruppe äquivalent (9,07±0,32 versus 9,90±0,27 log10 Zellen/g Fäzes TM [MW±SEM]; p<0,0019; Äquivalenzdifferenz von 1 log10 Zellen/g Fäzes TM) und höher als in der KON-Gruppe (8,27±0,31 log10 Zellen/g Fäzes TM [MW±SEM]). Die Zellzahl für Bifidobakterien war in der SYN-Gruppe am höchsten (11,54±0,05 versus 11,00±0,17 [REF-Gruppe] und 10,54±0,24 [KON-Gruppe] log10 Zellen/g Fäzes TM [MW±SEM]). In der SYN-Gruppe wurde die höchste Anzahl an Bifidobakterienspezies erfasst (167 mit [128 ohne] B. animalis in 56 Fäzesproben versus 98 und 93 in jeweils 51 Fäzesproben der REF- und KON-Gruppe). Neben Kinder-typischen Spezies wie B. bifidum und B. breve wurden auch Spezies, die für Erwachsene charakteristisch sind (B. adolescentis), häufiger in der SYN-Gruppe als in den Vergleichsgruppen nachgewiesen. Der pH-Wert in Fäzes von Kindern aus der SYN-Gruppe war niedriger als der aus der KON-Gruppe (6,07±0,20 versus 6,45±0,17 [MW±SEM]) und näher an dem von gestillten Kindern mit 5,29±0,12 (MW±SEM). Schlussfolgerung: Die Supplementation einer Säuglingsnahrung mit dem Synbiotikum aus CNCM I-3446 und Kuhmilcholigosacchariden führte zu einer Angleichung in der Zusammensetzung der intestinalen Mikrobiota und des fäkalen pH-Wertes an gestillte Kinder. Die in dieser Arbeit entwickelten groEL-basierten qPCR-Verfahren erlaubten eine spezifische und genaue Analyse der Bifidobakterienpopulation unter dem Einfluss eines Synbiotikums. / Background: Compared to formula-fed infants, breast-fed infants have a reduced incidence of gastrointestinal infections and atopic diseases. The health-promoting effect of breast milk is assumed to be partly mediated by the intestinal microbiota, which is characterized by a low diversity and a high proportion of bifidobacteria. Recent approaches in further development of infant formulae aim at promoting an intestinal microbiota similar to that of breast-fed infants. The supplementation of infant formula with probiotics (live microorganisms) or prebiotics (non-digestible carbohydrates, which serves as energy substrates for probiotic bacteria) could mimic the bifidogenic and antipathogenic, but also immunomodulating effect of breast milk. Due to various interactions with the gut microbiota and the immune system, the simultaneous administration of pro- and prebiotics (synbiotics) is focussed to have a synergistic effect. Objective and study design: In a randomized-controlled, clinical trial healthy full-term infants receiving an infant formula with synbiotic for the first three months of life were studied, whether an intestinal microbiota is induced, which is equivalent to that of breast-fed infants. The synbiotic consisted of Bifidobacterium animalis ssp. lactis CNCM I 3446 (previously known as B. lactis BB-12) and cow milk oligosaccharides. The study comprised two groups of infants receiving a starter formula with (SYN-group, n=21) or without supplement (KON-group, n=18). Breast-fed infants served as a reference (REF-group, n=23). In order to comprehensively characterize the bifidobacteria diversity at species level, quantitative real-time PCR (qPCR) assays based on the single-copy groEL as phylogenetic marker for the specific quantification of twelve bifidobacteria species in human feces were established and validated. Results: The supplemented formula was well tolerated and supported a healthy development; comparable anthropometric data of SYN- and REF-group. The synbiotic selectively stimulated the growth of lactobacilli and bifidobacteria. Lactobacilli levels were equivalent in SYN- and REF-group (9.07±0.32 versus 9.90±0.27 log10 cells/g feces DM [Mean±SEM]; p<0.0019; equivalence margin of 1 log10 cells/g feces DM) and higher than the KON-group (8.27±0.31 log10 cells/g feces DM [Mean±SEM]). The highest levels of bifidobacteria were observed in the SYN-group (11.54±0.05 versus 11.00±0.17 [REF-group] and 10.54±0.24 [KON-group] log10 cells/g feces DM [Mean±SEM]). The highest number of bifidobacteria species were obtained in the SYN-group (167 with [128 without] B. animalis in 56 fecal samples versus 98 and 93 in each of 51 fecal samples of the REF- and KON-group). Beside species, typically found in infants such as B. bifidum und B. breve, also species, which are characteristic for adults (B. adolescentis), were detected more often in the SYN-group than in the other study groups. Fecal pH was lower in the SYN- than in the KON-group 6.07±0.20 versus 6.45±0.17 [Mean±SEM]) and closer to that of breast-fed infants (5.29±0.12 [Mean±SEM]). Conclusion: In infants fed a starter formula supplemented with a synbiotic (CNCM I-3446 and cow milk oligosaccharides), composition of intestinal microbiota and fecal pH were closer to that of breast-fed infants. The groEL-based qPCR-assays, developed in this study, allowed a specific and accurate analysis of the bifidobacterial population in response to the synbiotic intake.
60

Avaliação dos efeitos do probiótico Bifidobacterium animalis subsp. lactis HN019 como terapia adjuvante no tratamento da periodontite experimental em ratos / Effects of the probiotic Bifidobacterium animalis subsp. lactis HN019 as an adjunct to treatment of experimental periodontitis in rats

Milla Sprone Tavares Ricoldi 06 March 2017 (has links)
Probióticos do gênero Lactobacillus estão sendo amplamente investigados no tratamento da periodontite. Contudo, os efeitos de microrganismos do gênero Bifidobacterium ainda são pouco conhecidos. Este estudo avaliou os efeitos do probiótico Bifidobacterium animalis subsp. lactis (B. lactis) HN019 como adjuvante à raspagem e alisamento radicular (RAR) no tratamento da periodontite experimental (PE) em ratos. No dia 0 do experimento, 32 ratos foram alocados em 4 grupos: C (controle), PROB (probiótico), PE-RAR e PE-RARPROB. Nos grupos PE-RAR e PE-RAR-PROB, a PE foi induzida pela colocação de ligaduras de seda ao redor dos primeiros molares inferiores dos animais. No 14&deg; dia, as ligaduras foram removidas e realizou-se a RAR. Nos animais dos grupos PROB e PE-RARPROB, o probiótico B. lactis HN019 foi administrado diariamente (10 mL/dia de 109 unidades formadoras de colônia) por 15 dias tendo seu início no 14&deg; dia do experimento. Os animais de todos os grupos foram submetidos à eutanásia 29 dias após o início do experimento. As hemimandíbulas e amostras de intestino delgado foram coletadas. Foram realizadas análises histomorfométricas, microtomográficas e imunohistoquímicas. Foram investigados, também, os efeitos microbiológicos de B. lactis HN019 no biofilme associado às ligaduras durante o desenvolvimento da PE. Todos os dados foram analisados estatisticamente. O Grupo PE-RAR-PROB apresentou menores reabsorção óssea alveolar e perda de inserção conjuntiva quando comparado ao Grupo PE-RAR, bem como menor número de osteoclastos, maior expressão de citocinas anti-inflamatórias e menor expressão de citocinas pró-inflamatórias (p <0,05). No grupo PE-RAR-PROB, os valores médios da profundidade da cripta do jejuno e duodeno foram significativamente maiores que aqueles do grupo PE-RAR. A proporção de bactérias aeróbias/anaeróbias foi maior nas amostras de biofilme de animais tratados com B. lactis HN019 em relação àquelas de animais não tratados (p <0,05). Dentro dos limites deste estudo, pode-se concluir que a utilização de B. lactis HN019 como adjuvante à RAR promove benefícios histológicos, microtomográficos e imunológicos adicionais no tratamento da PE em ratos, bem como melhora a morfologia intestinal. / Lactobacillus probiotics have been investigated in periodontitis. However, the effects of the genus Bifidobacterium on periodontitis are hardly known. This study evaluated the effects of the probiotic Bifidobacterium animalis subsp. lactis (B. lactis) HN019 as an adjunct to scaling and root planing (SRP) in rats with experimental periodontitis (EP). At baseline, 32 rats were assigned to 4 groups: C (control), PROB, EP-SRP and EPSRP- PROB. In groups EP-SRP and EP-SRP-PROB, the mandibular first molars of the animals received a ligature. At day 14, the ligatures were removed and SRP was performed. Animals of groups PROB and EP-SRP-PROB were orally administered with 10 mL/day of 109 colony forming units of B. lactis HN019 for 15 days, starting at day 14. Animals were euthanized at day 29. The jaws and samples of the duodenum, jejunum, and ileum were resected. Histomorphometric, microtomographic and immunohistochemical analyses were performed. Microbiological effects of B. lactis on biofilm were also evaluated. Data were statistically analyzed. Group EP-SRP-PROB presented reduced alveolar bone resorption and attachment loss when compared with Group EP-SRP (p<0.05). Group EP-SRP-PROB showed significantly fewer osteoclasts, increased expression of anti-inflammatory cytokines and reduced expression of proinflammatory cytokines compared with Group EP-SRP (p<0.05). In group EP-SRPPROB, the mean values of crypt depth of the jejunum and dudoenum were significantly higher than the ones from group EP-SRP. B. lactis promoted a higher ratio between aerobic and anaerobic bacteria in biofilm samples (p<0.05). Within the limits of this study it can be concluded that the use of B. lactis HN019 as an adjunct to SRP promotes additional histologic, microtomographic and immunologic benefits in the treatment of EP in rats and improves the intestinal morphology.

Page generated in 0.062 seconds