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Liserre, Alcina Maria. "Microencapsulação de Bifidobacterium lactis para aplicação em leites fermentados". Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-26042016-181206/.
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Bifidobacterium spp. são microrganismos probióticos que podem ser incorporados em produtos alimentícios. Entretanto, para que seus efeitos benéficos à saúde humana ocorram, é necessário que o número de células viáveis na hora do consumo seja, no mínimo, 106UFC/g. As bifidobactérias são sensíveis à elevada acidez e, por isso, torna-se necessária a busca por métodos que possam proteger a integridade da célula, sendo um deles a microencapsulação. Em uma primeira etapa do trabalho, Bifidobacterium lactis foi encapsulado em micropartículas de alginato e alginato modificado (alginatoquitosana, alginato-quitosana-sureteric e alginato-quitosana-acryl-eze) e sua sobrevivência e liberação das micropartículas em fluidos simulados do trato gastrintestinal foram mensuradas utilizando-se soluções tampão com pH 1,5, 5,6 e 7,5, na presença e na ausência de pepsina (3g/L), pancreatina (1g/L) e bile (10g/L). A liberação de células das micropartículas teve uma relação direta com o pH do tampão. A microencapsulação aumentou a taxa de sobrevivência de B. lactis, em comparação com células não encapsuladas, em soluções tampão com pH 1,5 sem a presença de enzimas. Em suco gástrico simulado com enzimas digestivas, por outro lado, foi observado que a pepsina proporcionou um efeito protetor sobre as células de B. lactis, e nesse caso, as taxas de sobrevivência do microrganismo estavam diretamente relacionadas com o grau de injúria das células. Em uma segunda etapa do trabalho, leites fermentados com Streptococcus salivarius ssp. thermophilus e Lactobacillus delbrueckii ssp. bulgaricus foram enriquecidos com culturas de Bifidobacterium lactis submetidas a quatro tratamentos diferentes: desidratação em temperatura ambiente, liofilização/congelamento, encapsulação em alginatoquitosana e encapsulação em alginato-quitosana-acryl-eze. A população sobrevivente de B. lactis foi determinada semanalmente no leite fermentado e também após tratamento simulando condições do trato gastrintestinal. Os resultados indicaram que na ausência de pepsina, as populações de B. lactis foram reduzidas drasticamente após o contato com tampão pH 1,5, não sendo possível a detecção de células viáveis livres ou encapsuladas após 120 minutos de teste. A presença de pepsina influenciou positivamente a recuperação de células viáveis de B. lactis em todas as condições testadas, mas as culturas na forma desidratada apresentaram melhores resultados que as culturas microencapsuladas ou liofilizadas. No caso do leite fermentado contendo as células desidratadas, a população de B. lactis, após o tratamento em suco gástrico com enzimas, foi superior à detectada no produto antes desse tratamento. Conclui-se que a microencapsulação não foi eficiente para proteger B. lactis em leite fermentado contra injúrias causadas pelo trato gastrintestinal simulado.Bifidobacterium spp. are microorganisms that can be added to foods. However, the benefits for the human health occur when the numbers of viable cells in the moment of the consumption is at least 106CFU/g. Bifidobacteria are acid sensitive, and methods to protect cell integrity, such as microencapsulation, are needed. In the first part of the present study, Bifidobacterium lactis was encapsulated in microparticles of alginate and modified alginate (alginate-chitosan, alginate-chitosan-sureteric and alginate-chitosan-acryl-eze) and the survival and release from microparticles in simulated gastrointestinal conditions were measured, using buffers (pH 1.5, 5.6 and 7.5), in the absence and presence of pepsin (3g/L), pancreatin (1g/L) and bile. The release from microparticles presented a direct relationship with pH. When the pH was 1.5 and no enzyme was present, encapsulation improved the survival of B. lactis, when compared to free cells. However, pepsin had a protective effect on B. lactis, and the survival rate was directly related to the cells injury degree. In the second part of the study, fermented milk samples containing Streptococcus salivarius ssp. thermophilus and Lactobacillus delbrueckii ssp. Bulgaricus were supplemented with B. lactis submitted to four different treatments: dehydration at room temperature, freeze drying, encapsulation in alginate-chitosan and encapsulation in alginate-chitosaacryl-eze. The number of viable B. lactis cells in the fermented milk was determined weekly and also after treatment with simulated gastrointestinal conditions. Results indicated that in the absence of pepsin, the number of viable cells decreased significantly after contact with buffers (pH 1.5), and no viable cell was detected after 120 minutes. Pepsin improved the recovery of viable cells in the assayed gastric conditions, being the dehydrated cultures more resistant than other cultures. In fermented milk containing the dehydrated cells, the number of viable cells increased after treatment with simulated gastrointestinal fluids. Microencapsulation was not an effective procedure to protect B. lactis in fermented milk against injury caused by the simulated gastrointestinal tract.
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Oberg, Taylor S. "Characterization of the Hydrogen Peroxide Stress Responses of Bifidobacterium longum and Bifidobacterium animalis subsp. Lactis". DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/2037.
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Probiotics are living organisms which exert a beneficial health effect when consumed in sufficient numbers. Consumer interest in probiotics has increased dramatically in recent years prompting an increase in production and development of functional foods. One major problem is the decreased viability of probiotic bacteria during functional food production and storage and subsequent digestion due to environmental stresses. The most common probiotic strains belong to the genus Lactobacillus or Bifidobacterium. Due to the anaerobic nature of these bacteria, they lack the required defense mechanisms for oxidative stress inherent in aerobic microorganisms. This study examined the oxidative stress responses of six strains of Bifidobacterium, which are commonly used as probiotics in functional foods.The first phase of the study investigated the innate and inducible hydrogen peroxide (H2O2) stress response of Bifidobacterium longum strains NCC2705 and D2957, Bifidobacterium longum ssp. infantis ATCC 15697, and Bifidobacterium animalis ssp. lactis strains BL-04, DSM10140 and RH-1. Strains were screened for survival at increasing concentrations of H2O2 and lethal and sublethal concentrations were determined for each. In the second phase, B. animalis ssp. lactis strains BL-04 and DSM10140 and B. longum strains NCC2705 and D2957 were treated with a sublethal H2O2 concentration and RNA samples were collected for transcriptome analysis after 5 min and either 20 or 60 min. Statistical analysis was performed to identify genes that increased or decreased in expression during H2O2 treatment compared to control cells.Results showed that survival was species and strain dependent and that strains which naturally survived higher H2O2 concentrations had a larger number of differentially expressed genes early on during H2O2 exposure. Some of the protective genetic systems that were activated during H2O2 stress are mechanisms which perform basic cellular functions under normal conditions such as deoxuynucleotide synthesis. Under stress conditions, these systems can be used to detoxify oxidative free radicals. Also a number of genes involved in sugar transport and energy production for the cell showed increased expression, which reveals the increased energy needs of the cells during oxidative stress.During testing, it was found that two B. animalis ssp. lactis strains, BL-04 and DSM10140, had differing levels of survival and gene expression during H2O2 exposure despite having almost identical genome sequences. It was determined that one possible cause of the differences was a genetic deletion in a gene that allows the cell to incorporate extracellular fatty acids into the cell membrane instead of synthesizing them.Results from this project have increased the understanding of oxidative stress responses in bifidobacteria and highlighted possible methods to increase bacterial survival during food manufacture, storage, and human digestion.
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Martinez, Fabio Andres Castillo. "Produção de bacteriocina por Bifidobacterium lactis a partir de leite desnatado". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/9/9135/tde-16012014-134005/.
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Existe um número muito limitado de estudos referentes à produção de componentes antimicrobianos ou bacteriocinas produzidas por espécies de bifidobactérias. Nesse âmbito, o objetivo deste trabalho foi avaliar a produção de bifidobacteriocina em leite desnatado (LD). Para tanto, o estudo foi dividido em três etapas. A primeira etapa constituiu na preparação dos meios de cultura Man, Rogosa e Sharpe (MRS), Bifidus Selective Medium (BSM) e LD suplementado com 1% (p/v) de Tween 80 (T80), Inulina (I) ou Extrato de levedura (YE). Nesta etapa, os processos fermentativos foram conduzidos em shaker, nas condições: 50 rpm/37ºC/48h. Foram realizadas análises de pH, concentração de açúcares e ácidos, crescimento celular e determinação da atividade da bifidobacteriocina pelo método de difusão em ágar contra L. monocytogenes. Na segunda etapa, e baseado nos resultados obtidos, foi desenhado um delineamento composto central (CCD) construído a partir dos seguintes parâmetros: temperatura (34, 37, 40 °C) e concentração de YE (0,5; 1,0; 1,5 g/L). Na terceira etapa do trabalho, foram realizados os cultivos em biorreator de 2 L, contendo 10% de leite desnatado, nas seguintes condições: 200 rpm, 36°C, 2,0 g/L de YE, 48h de incubação em anaerobiose. Obteve-se em LD suplementado com YE (1%), combinado ao método de difusão em placa modificado (prévia refrigeração das placas por 12h), contra L. monocytogenes (2130 AU/mL), com uma fase exponencial de 24h, µm de 0,604/h. A otimização feita através do CCD permitiu atingir níveis de atividade de 3.000 AU/mL a 3.100 AU/mL (ensaios 7, 11 e 14, blocos 3 e 1) contra L. monocytogenes, em condições ótimas de crescimento de YE: 2,0 g/L1 e T°C: 36°C. A análise de regressão mostrou ser estatisticamente significativa a relação entre as variáveis: \"concentração de \"YE e temperatura\". Os resultados indicaram que o leite desnatado é um meio adequado para produção de bifidobacteriocina.There are few publications that have been reported about bacteriocin production by Bifidobacterium species. Therefore, the aim of this work was measure bacteriocin production in skim milk by B. lactis. Consequently, this work was divided in three stages. First, MRS, BSM and LD medium were tested with additives (Tween 80 (T80), Inuline (I) or Yeast extract (YE)) for bacteriocin production and cellular growth. Fermentation processes were conducted in shaker under specific conditions: 50 rpm/37ºC/48h. pH; sugars; acids; biomass, and bacteriocin activity against L. monocytogenes, L. plantarum, E. coli, L. sakei e S. aureus strains were analyzed . In the second stage, based on the obtained results, a central composite design (CCD) was created using the parameters: temperature (34, 37, 40 ºC), and concentration of YE (0.5, 1.0, 1.5 g/L). After, the activity was measured by two methods of plates pre-diffusion (cooling and addition of Tween 20). Third step consisted of 2 L bioreactor cultivations containing 10% skim milk diluted in 1.5 L of water (6.5 pH), under 200 rpm, 36 ºC, 2.0 g/L of YE, 48h, under anaerobic condition. Finally, the cultures supplemented with LD and YE (1%) with a modified plate diffusion method (cooling plates for 12 h) showed bacteriocin activity against L. monocytogenes (2130 AU/mL) with an exponential phase of 24 h, µm of 0.604/h. The optimization performed using CCD resulted in a higher level of activity 3000 AU/mL to 3100 AU/mL mL (Run 7, 11 and 14, blocks 3 and 1) against L. monocytogenes, also with ideal growth conditions of YE: 2,0 g/L1 and T °C: 36 °C. The pH value varied between 6.4 and 4.0. Concentration of produced acid lactic varied from 3.03 to 4.72 g/L and biomass concentration from 3.4 to 11.1 Lg UFC/mL. Regression analysis was significant to the variables: YE concentration and temperature. Results indicated that skim milk is a proper medium for \"Bifidobacteriocin\" production.
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Trindade, Marla. "Studies on carbohydrate metabolism in Bifidobacterium : isolation, characterisation and regulation of a sucrose-utilisation gene cluster in Bifidobacterium lactis". Doctoral thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/4341.
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Bibliography: leaves 167-195.The primary aim of the project was, therefore, to analyse carbohydrate metabolism for the identification of and/or the development of prebiotic substrates, and to provide a molecular characterisation for their utilisation. Several carbohydrates were tested for their ability to support the growth of bifidobacteria as a sole carbohydrate source. The four bifidobacterial strains, B. breve, B. bifidum, B. longum and B. lactis were able to utilise a wide variety of substrates.
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Balciunas, Eduardo Marcos. "Produção de bacteriocina por Bifidobacterium lactis a partir de soro de leite". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/9/9135/tde-13112013-142452/.
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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.
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Silveira, Ericka Oliveira da. "Desenvolvimento de bebida láctea achocolatada de cabra contendo Bifidobacterium lactis, inulina e Frutooligossacarídeos". Universidade Federal da Paraíba, 2014. http://tede.biblioteca.ufpb.br:8080/handle/tede/4071.
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Previous issue date: 2014-06-06Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The development of functional goat dairy products is a viable alternative to add value to goat milk and to popularize new functional foods, considering the growing demand for foods with high nutritional quality, tasteful and promoters of well-being and health. This study aimed to produce chocolate goat dairy beverages with the probiotic Bifidobacterium lactis and evaluate the effects of goat cheese whey and prebiotics (inulin and oligofructose) on the physicochemical parameters and sensory features of the beverages during 28 days of refrigerated storage. Seven formulations of dairy beverages were analyzed for protein, fat, ash and lactose immediately after production, and submitted to physicochemical analysis (titratable acidity, total solids, pH, syneresis, apparent viscosity) and microbiological analysis, including B. lactis viability, after 1, 7, 14, 21 and 28 days. Sensory acceptability was determined after 14 days. All formulations had decreased pH and concomitant increase in the acidity during refrigerated storage. Beverages made with the lowest amounts of whey (F1 and F3) had greater decrease in pH from 14 days of storage. The apparent viscosity increased up to 21 days for all formulations, and up to 28 days for F4 (6 g 100 g - 1 prebiotics and 45 mL 100 mL -1 whey), possibly related to the higher amounts of whey and inulin. B. lactis showed counts between 6 and 8 log CFU mL-1. F4 presented the highest average in sensory attributes flavor and aroma. Apparently, larger amounts of prebiotics and whey in the beverage enhance the flavor perception, which may be a consequence of the intensification of cocoa flavor and / or lower acidity perception. Thus, F4 was the formulation that best represented the desirability profile chosen for the probiotic chocolate goat dairy beverage as best viscosity and improved sensory features.
O desenvolvimento de derivados lácteos funcionais de cabra é uma alternativa viável para agregação de valor ao leite de cabra e popularização de novos alimentos funcionais, considerando a crescente demanda por alimentos com qualidade nutricional, sabor agradável e promotores de bem-estar e saúde. O objetivo deste estudo foi elaborar bebidas lácteas achocolatadas de cabra (F1 a F7) contendo Bifidobacterium lactis e avaliar os efeitos do soro de queijo de cabra e do prebiótico Synergy 1® (inulina e oligofrutose) sobre as propriedades físico-químicas e sensoriais durante 28 dias de armazenamento refrigerado. As bebidas lácteas foram avaliadas imediatamente após a fabricação quanto à proteína, gordura, cinzas e lactose, submetidas às análises físico-químicas (acidez titulável, sólidos totais, pH, sinérese, viscosidade aparente) e microbiológicas, incluindo a viabilidade da B. lactis, durante o armazenamento após 1, 7, 14, 21 e 28 dias. Após 14 dias de armazenamento foi determinada a aceitabilidade sensorial. Todas as formulações tiveram uma diminuição do pH concomitante a um aumento na acidez ao longo do armazenamento refrigerado. As bebidas formuladas com menor quantidade de soro (F1 e F3) tiveram uma queda maior no pH a partir de 14 dias de armazenamento. As formulações F3 e F4 (contendo 6 g 100 g-1 de prebiótico) apresentaram teor de sólidos totais significativamente mais elevados. A viscosidade aparente aumentou até 21 dias em todas as formulações, e para F4 (maiores proporções de soro e de prebióticos - 45 mL 100 mL-1 e 6 g 100 mL-1 - respectivamente) este aumento se estendeu até os 28 dias, possivelmente relacionado à influência do soro e da inulina. Durante todo o período estudado B. lactis apresentou contagens entre 6 e 8 log UFC mL-1, sendo a maior viabilidade observada para a formulação F1 (8,13±0,03 UFC mL-1). A maior mediana nos atributos sabor e aroma foi observada para F4. Aparentemente uma maior quantidade de prebiótico na bebida melhorou a percepção do sabor, o que pode ser uma consequência da intensificação do sabor de cacau e ou da menor percepção da acidez. Já o aumento do soro melhorou a percepção do aroma na bebida láctea. Assim, F4 foi a formulação que melhor representou o perfil de desejabilidade escolhido para a bebida láctea probiótica achocolatada de cabra, como melhor viscosidade e características sensoriais.
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Kokott, Shaun. "Microencapsulation and supply of Bifidobacterium lactis DSM 10140 in fermented traditional African beverages". Thesis, Cape Technikon, 2004. http://hdl.handle.net/20.500.11838/824.
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Thesis (MTech (Food Technology))--Cape Technikon, 2004Probiotic foods are intended to supply selected viable microorganisms, for example Lactobacillus acidophilus and Bifidobacterium, to consumers. These organisms, when consumed at the daily intake of 108 , provide benefits beyond basic nutrition. Probiotic (AB) foods generally include fermented dairy products such as yoghurts and cheeses, targeted at the upmarket consumer. However, due to technical problems associated with the foods and the organism, viable Bifidobacterium rarely occur in AB foods. The principle aims of this study were to develop a suitable delivery system for Bifidobacterium to the consumer, and to supply these living organisms in the affordable traditional fermented African beverages, amasi and mahewu. This would provide the benefits of probiotics to the rural African consumer, where malnutrition and gastrointestinal diseases occur. The organism selected for this study was Bifidobacterium lactis DSM 10140, commonly associated with AB starter cultures for yoghurts. The delivery system selected was microencapsulation of B. lactis using a mixture of the generally recognised as safe (GRAS) edible gums, gellan and xanthan. Supply vehicles for the microcapsules to the consumer were amasi and mahewu. Prior to microencapsulation, rheological studies were undertaken to determine whether the gellan-xanthan gum mix would provide a suitable support matrix for microencapsulated B. lactis. This was done using a Paar Physica MGR 300 rotational rheometer with a cone plate 50-2 measuring system. Results indicated that the hydrated gellan-xanthan gum mix behaved as a non-Newtonian material, and the flow curve fitted well to the Herschel-Bulkley model. This demonstrated that the gel was a relatively viscous material with solid properties. The average yield stress of the gel was 1.515 Pa, indicating that the gel was stable, and at lower stresses would behave as a solid. The gel mix would be disrupted by shear stresses associated with mastication and peristalsis. The minimum viscosity of the gel was constant at temperatures between 46°C - 61°C. It was concluded from these data that the gel was suitable for microencapsulation and that microcapsules should only be included in soft foods, which do not require chewing. Temperatures associated with microencapsulation, at minimum gel viscosities, were not lethal to B. lactis. Bifidobacterium lactis cells were incubated under anaerobic conditions (4% H2, 10% CO2, and 86% N2) at 37°C overnight in 250 ml Tryptone-Yeast-Glucose (TYG) broth, and grown to an 00600 0.9 - 1.1. Cells were harvested and washed for microencapsulation using centrifugation. Microencapsulation of the organism was done using a mono-axial extrusion technique together with a superposed airflow, by manually extruding the aqueous gum I cell mix through a 27.5 G bevelled needle, fitted on to a 10 ml syringe. The resultant microdroplets were hardened by free fall into 0.1 M CaCI2 solution. Microcapsules were separated from the CaCI2 solution by filtration through Whatman No.1 filter paper. All procedures were carried out in a laminar flow hood. Results indicated that the method of microencapsulation used in this study was successful. Using a concentrated inoculum of B. lactis, high numbers (lOglO 11-12 etu.g-1 ) of bacteria were incorporated into the microcapsules. Therefore the daily intake would be provided by 0.1 g microcapsules. The diameter and size distribution of microcapsules were determined by laser diffractometry. This showed a maximum microcapsule diameter of 2.22 mm with 50% (w/v) of the microcapsules having a diameter of < 0.637 mm. Although this represents a considerable size variation, this would not adversely affect mouthfeel of the beverages, as only 0.1 g microcapsules would be required to obtain at least 108 B. lactis in any volume of amasi or mahewu. To enumerate immobilised viable B. lactis, two techniques were compared. These involved the use of either a pestle and mortar, or high power ultrasound (HPUS) (20 kHz, 750 W). Results showed that HPUS was superior to the pestle and mortar technique. A short exposure (15 s) to HPUS disrupted the matrix releasing all entrapped etus, whereas when using the pestle and mortar xiii technique, cells remained partially entrapped in the gel. Therefore the pestle and mortar technique yielded lower cfu values than expected. The survival of microencapsulated B. lactis, in 1 M sodium phosphate buffer, was studied as a possible means of supply of microcapsules to industry for incorporation into foods. Microcapsules were stored in the buffer for 21 days at either 4°C or 22°C. Results showed that cell viability was not significantly reduced (p>0.05) at either temperature after 21 days. Hence this form of storage could be used to deliver viable immobilised B. lactis to the food industry. In order to assess the survival of immobilised B. lactis in the GIT, the microcapsules were incubated at 37°C over a period of 240 min in simulated gastric juice (SGJ) (pH 1.5). Viable counts were performed by sampling at regular intervals. A similar study was done in simulated bile and pancreatic juices (BPJ) (pH 6.5). In SGJ, it was demonstrated that there was a significant reduction (3 log cycles) (p<0.05) of free cells after 240 min. However, this trend was not noted for microencapsulated B. lactis. Therefore, the gellanxanthan gel matrix protected B. lactis from the lethal effect of SGJ. In BPJ, no significant difference (p>0.05) was noted for surviving fractions of both immobilised and free B. lactis. Commercial pasteurised amasi (pH 4.4) and mahewu (pH 3.5) were selected as the supply vehicles for the microencapsulated B. lactis. Known numbers of viable microencapsulated and free B. lactis cells were added to both beverages. For most samples, incubation was at either 4°C or 22°C for 21 days in the presence of atmospheric oxygen. In addition, free cells were incubated anaerobically at 22°C. As oxygen is limiting in the microcapsules, these were not incubated under anaerobic conditions. The survival I shelf-life studies of commercial amasi indicated no significant difference (p>0.05) in survival rate between immobilised and free B. lactis cells. The reduction noted for viable counts of immobilised or free B. lactis cells was approximately 1.5 log cycles. Even so, after 21 days viable immobilised B. lactis (1010 0.1 g'l microcapsules) remained in excess of the daily intake 108 , whereas in the free B. lactis cells, the viable count declined to 106 mr1 . Statistical analyses showed that temperature or oxygen presence had little effect on the survival of both immobilised or free B. lactis cells (p>O.05). In mahewu, decline in viability of cells was observed for most samples. However microencapsulation enhanced cell survival at both 4°C and 22°C when compared to free cells. The decrease in viable B. lactis free cells occurred more rapidly (3 log cycles) in mahewu, than in amasi, at both 4°C and 22°C. Throughout the shelf-life studies it was apparent that viable B. lactis cell numbers did not increase. This was advantageous as metabolites associated with B. lactis growth would have adversely altered the taste of both amasi and mahewu. Sensory evaluation of the traditional fermented African beverages, enriched with either viable immobilised or free B. lactis, was done in order to determine consumer response to the product. An analytically trained 12-member taste panel analysed the beverages for colour, texture, and taste. The triangle taste test procedure was used. No differences were detected with regard to texture, and colour of the fermented beverages containing immobilised B. lactis. However, in the fermented beverages containing free cells, a change in viscosity was noted. There was a significant difference (p
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Medeiros, Adja Cristina Lira de. "Iogurte caprino probiótico em pó: estudo do processo de secagem, da caracterização do pó e da viabilidade do probiótico". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-22052013-102129/.
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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.
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Sousa, Ana Lucia Orlandini Pilleggi de. "Viabilidade de Bifidobacterium animalis subsp. lactis HN019 em fórmulas infantis probióticas durante o armazenamento a 4 ºC". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/9/9133/tde-22082013-122441/.
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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.
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Schossler, Luiza Sawitzki. "ESTUDO DA VIABILIDADE DE MICRORGANISMO PROBIÓTICO (BIFIDOBACTERIUM ssp lactis) APLICADO EM PRODUTO CÁRNEO COZIDO". Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/5671.
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This project was developed to prepare a cooked meat product, Ham Pate, with probiotic properties from the inoculation of the Bifidobacterium lactis probiotic organism in a concentration capable of ensuring its viability in the product. Ham pâté was processed in two
different treatments and a control. Control (C) without addition of probiotic microorganisms; treatment 1, (T1) with the addition of probiotic microorganisms, Bifidobacterium lactis, in a final concentration expected in the product of 106 UFC. g-1; and, treatment 2 (T1) with the addition of probiotic microorganisms, Bifidobacterium lactis, in a final concentration expected
in the product of 108 UFC. g-1. Preliminary tests of culture sensitivity to the sodium chloride (NaCl) and salt of curing (NaNO2) were performed. The concentrations of (NaCl) added to MRS agar were 1.0%, 1.5% and 2.0%, and (NaNO2) was added in 150, 200 and 250ppm. Tests with the combination of NaCl and (NaNO2) were also performed to verify the front line to the combination of these two salts, using the same concentrations, but combined. It was
observed a growth of Bifidobacterium in all tests, that showed its resistance and suitability for using it in processed meat products that have these ingredients in their formulations. The developed product was tested by physical-chemical analysis (proximate composition, pH and
TBARS), microbiological (coliform at 45º C, Clostridium perfringes, Staphylococcus coagulase positive, Salmonella sp. and Bifidobacterium lactis) and sensory. It was observed through the result of proximate composition analysis and pH that the product met all the requirements established by legislation. The determination of lipid oxidation by determination of thiobarbituric acid reactive substances (TBARS) showed that the control treatment
resulted in lipid oxidation evolution much higher than other treatments (T1 and T2), suggesting that the probiotic microorganisms had an influence on stability of the product on the oxidation of lipids. The number of Bifidobacterium lactis viable cells showed in T1 initial
concentrations of 5.6 x 106UFC. g-1, in the 14th day of the analysis fell into a cycle log. reaching in the 31st day a counting of viable cells of 4.3 x 105UFC.g-1, the T2 had initial concentration of 8.4 x 108UFC.g-1, suffering a dropping of 1 log cycle in the 31st day, ending with a concentration of 1.5 x 107 CFU. g-1. So, it s possible to conclude that treatment T1 was viable as probiotic food (counting at least 106UFC.g-1), for 14 days, while the treatment T2 was viable as probiotic during the entire period of analysis, in other words, for 31 days. The
sensory analysis showed that there was no significant difference (p <0.05) for overall acceptance of treatments T1 and T2, both having a good acceptance on the test of the
product purchase intention. Thus, it s possible to observe that there is a feasibility of probiotic microorganisms application in cooked meat products, such as ham pâté, it has more acceptance and it can be served alternative to the development of meat products with functional properties.O presente projeto foi desenvolvido com o objetivo de elaborar um produto cárneo cozido, patê de presunto, com propriedades probióticas, a partir da inoculação do microrganismo probiótico Bifidobacterium lactis em concentração capaz de garantir a sua viabilidade no produto. O patê de presunto foi processado em dois diferentes tratamentos e um controle. Controle (C) sem adição de microrganismo probiótico; tratamento 1 (T1) com adição de microrganismo probiótico, Bifidobacterium lactis, em uma concentração final esperada no produto de 106 UFC. g-1; e, tratamento 2 (T2) com adição de microrganismo probiótico Bifidobacterium lactis, em uma concentração final esperada no produto de 108 UFC. g-1. Testes preliminares de sensibilidade da cultura ao cloreto de sódio (NaCl), e sal de cura (NaNO2) foram realizados. As concentrações de NaCl adicionadas ao Ágar MRS foram de 1,0%, 1,5% e 2,0%, e de NaNO2 adicionada ao mesmo meio foram de 150, 200 e 250ppm. Testes com a combinação de NaCl e NaNO2 também foram realizados para verificar o comportamento da linhagem frente à combinação destes dois sais, utilizando as mesmas concentrações, porém combinadas. Foi observado um crescimento expressivo das Bifidobactérias em todos os testes, o que ressaltou a sua resistência e possibilidade de utilização em produtos cárneos processados, que têm em suas formulações estes ingredientes. O produto desenvolvido foi avaliado através de análises físico-químicas (composição centesimal, pH e TBARS), microbiológicas (Coliformes a 45ºC, Clostridium perfringes, Staphylococcus coagulase positiva, Salmonella sp. e Bifidobacterium lactis) e sensoriais. Verificou-se através do resultado da análise da composição centesimal e do pH que o produto atendeu a todas as exigências estabelecidas pela legislação. As determinações de Oxidação Lipídica através da determinação das substâncias reativas ao ácido tiobarbitúrico (TBARS) mostraram que o tratamento controle apresentou uma evolução na oxidação lipídica superior aos outros tratamentos (T1 e T2), sugerindo que os microrganismos probióticos apresentaram uma influência na estabilidade do produto quanto à oxidação dos lipídios. A estimativa da população de Bifidobacterium lactis apresentou no T1 concentrações iniciais de 5,6 x 106 UFC. g-1, a partir do 14º dia de armazenamento houve queda de um ciclo log. chegando ao 31º dia com uma população estimada de 4,3 x 105 UFC. g-1; o T2 apresentou concentração inicial de 8,4 x 108 UFC.g-1, sofrendo uma queda de 1 ciclo logarítmico no 31º dia, terminando com uma concentração de 1,5 x 107 UFC. g-1. Portanto, pode-se constatar que o tratamento T1 apresentou viabilidade como alimento probiótico (contagem mínima de 106UFC.g-1), por 14 dias, enquanto que o tratamento T2 apresentou-se viável como probiótico durante todo o período de análises, ou seja, por 31 dias. A análise sensorial realizada demonstrou que não houve diferença significativa (p < 0,05) quanto à aceitação global dos tratamentos T1 e T2, tendo ambos uma boa aceitação quanto ao teste de intenção de compra do produto. Desta forma pode-se observar que existe a viabilidade de aplicação dos microrganismos probióticos em produtos cárneos cozidos como o patê de presunto e que este possui aceitação podendo servir como alternativa no desenvolvimento de produtos cárneos com propriedades funcionais.
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Oliveira, Luiz Fernando Ferreira de. "Administração tópica do probiótico Bifidobacterium animalis subsp. lactis HN019 reduz a destruição tecidual periodontal em ratos com periodontite experimental: estudo histológico, microtomográfico, imunológico e microbiológico". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/58/58132/tde-24052016-092031/.
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O objetivo deste estudo foi avaliar os efeitos da administração tópica de bactérias probióticas do gênero Bifidobacterium na doença periodontal experimental em ratos. Foram utilizados 32 ratos divididos nos seguintes grupos: CT (controle), DPT (doença periodontal), CT-HN019 (controle + probiótico) e DPT-HN019 (doença periodontal + probiótico). No dia 0 do experimento, a doença periodontal foi induzida nos animais dos grupos DPT e DPT-HN019 por meio da colocação de ligaduras ao redor dos primeiros molares inferiores. Nos Grupos CT-HN019 e DPT-HN019, 2 mL de uma suspensão contendo 109 unidades formadoras de colônia/mL de Bifidobacterium animalis subsp lactis (B. lactis) HN019 foram administrados topicamente na região subgengival dos primeiros molares inferiores nos dias 0, 3 e 7 do experimento. Nos grupos CT e DPT, as administrações tópicas foram realizadas com uma suspensão sham (sem probiótico). Todos os animais foram submetidos à eutanásia 14 dias após o início do experimento. Foram coletados tecido gengival, hemi-mandíbulas e biofilme bucal para avaliação dos seguintes parâmetros: i) microbiota bacteriana (checkerboard DNA-DNA hybridization; ii) expressão de citocinas pró e anti-inflamatórias (análise Multiplex); iii) imunorreatividade de peptídeos antimicrobianos (reações imunohistoquímicas - estreptavidina-biotina-peroxidase); iv) níveis inserção conjuntiva (análise histomorfométrica) e v) microarquitetura e volume ósseos (microtomografia computadorizada por transmissão de raios X). Os dados obtidos foram submetidos à análise estatística (p < 0,05). O grupo DPT apresentou maiores valores de porosidade óssea, espaçamento de trabéculas ósseas e nível de inserção conjuntiva, bem como menor número de trabéculas e volume ósseos quando comparado a todos os outros grupos (p < 0,05). No Grupo DPT-HN019, foram observados maiores percentuais de bactérias dos complexos amarelo e azul, bem como maiores expressões de Osteoprotegerina (OPG), Beta-defensina (BD)-1, BD-2 e BD-3 quando comparados àqueles do Grupo DPT (p < 0,05). O Grupo DPT apresentou níveis de Interleucina (IL)-1β Receptor Ativador do Fator Nuclear Kappa-beta (RANKL) maiores que aqueles do Grupo DPT-HN019 (p < 0,05). As razões RANKL/OPG e IL-1β/IL-10 foram mais elevadas no grupo DPT do que no Grupo DPT-HN019 (p < 0,05). Dentro dos limites deste estudo pode-se concluir que o uso tópico de B. lactis HN019 promove um efeito protetor contra a perda óssea e de inserção conjuntiva decorrentes da periodontite experimental em ratos.The purpose of this study was to evaluate the effects of topical administration of probiotic bacteria of the genus Bifidobacterium on experimental periodontal disease in rats. 32 rats were divided into groups C (control), EP (experimental periodontitis), C-HN019 (control + probiotic) and EP-HN019 (EP+ probiotic). On day 0 of the experiment, periodontitis was induced in the animals of groups EP and EP-HN019 through the placement of ligatures around mandibular first molars. In groups C-HN019 and EP-HN019, 2 mL of suspensions containing 109 colony-forming units/mL of Bifidobacterium animalis subsp lactis (B. lactis) HN019 were topically administered in the subgingival region of mandibular first molars on days 0, 3 and 7 of the experiment. In groups C and EP, topical administrations were performed using a sham suspension (without probiotic). All animals were euthanized 14 days after the beginning of the experiment. Gingival tissue, hemi-mandibles and oral biofilm were collected for evaluation of the following parameters: i) bacterial microbiota (checkerboard DNA-DNA hybridization), ii) expression of pro- and anti-inflammatory cytokines (Multiplex analysis), iii) immunoreactivityof antimicrobial peptides (immunohistochemical reactions - streptavidin-biotin-peroxydase); iV) connective tissue attachment levels (histomorphometric analysis) and v) bone microarchitecture and volume (microtomographic analysis). Data were statistically analyzed (p < 0.05). Group EP presented greater values of bone porosity, trabecular separation and connective tissue attachment loss as well as reduced trabecular number and bone volume when compared with all the other groups (p < 0.05). In group EP-HN019, there were greater percentages of bacteria of the yellow and blue complexes and greater expressions of Osteoprotegerin (OPG) and beta-defensins (BD)-1, BD-2 and BD-3 when compared with group EP (p < 0.05). Group EP presented greater levels of Interleukin (IL)-1β and Receptor Activator of Nuclear Factor-Kappa B ligand (RANKL) than group EP-HN019 (p < 0.05). The increase in the ratios RANKL/OPG and IL-1β/IL-10 was greater in group EP than in group EP-HN019 (p < 0.05). Within the limits of the present study, it can be concluded that the topical use of B. lactis HN019 promotes a protective effect against alveolar bone and connective tissue attachment losses attributable to experimental periodontitis in rats.
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Rodrigues, Antonio Carlos. "Desenvolvimento e avaliação de cheesecake light potencialmente funcional e simbiótico". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-26092014-100625/.
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Este trabalho teve como objetivo o desenvolvimento e a avaliação das propriedades funcionais, físico-químicas, reológicas, sensoriais de preferência pareada (do cheesecake e de sua cor) e microbiológica (contagens de coliformes fecais/totais e da bifidobactéria) do cheesecake manufaturado com farinha de trigo (ou amido de milho ceroso modificado), queijo fresco, sacarose, eritritol (como substituinte parcial de sacarose), ovos in natura, manteiga [ou frutoligossacarídeos (FOS) - prebiótico - como substituinte da manteiga], curcumina e Bifidobacterium animalis subespécie lactis BB-12 (probiótico). A análise estatística dos dados considerou a existência quatro grupos experimentais, sendo: [2 cheesecakes lights (em açúcar e gordura) potencialmente funcional e simbiótico: T1= farinha de trigo e FOS; T2 = AMCM e FOS] e [2 cheesecake light (em açúcar) potencialmente funcional e probiótico: T3 = farinha de trigo e manteiga; T4 = AMCM e manteiga]. Foi estabelecido um tratamento T0 como padrão da Tese, adaptado da formulação da QuarkTorte por Henning Fleissig (Alemanha). As variáveis de resposta foram do tipo quantitativa, considerando unidades formadoras de colônias (UFC) de bactérias láteas, unidade formadora de colônias (UFC) de coliformes totais e fecais, pH, atividade da água, dureza, adesividade, elasticidade, coesividade, gomosidade e mastigabilidade. Estas variáveis de respostas compuseram um modelo de Análise de Variância com medidas repetidas, pois as unidades experimentais foram observadas após 1, 8, 15, 22 e 28 dias. Medidas (como médias, medianas e desvio padrão), gráficos e ANOVA, foram geradas pelo pacote estatístico STATA® - versão 9.0. Os resultados da ANOVA não mostraram resultados estatisticamente significativos que indicassem existir diferenças entre os grupos experimentais [p-value: 0,7981; 0,4204; 0,9974; 0,6825; 0,6401; 0,4800; 0,6469; 0,4258; 0,4615] e nem entre os valores ao longo do tempo, dentro de cada grupo experimental [p-value: 0,1725; 0,0000; 0,4076; 0,8957; 0,8787; 0,0001; 0,6214; 0,8845; 0,6820] [p-value correspondentes respectivamente a: log de UFC de bactérias láteas; pH; atividade de água (aw); mastigabilidade; gomosidade; coesividade; elasticidade; adesividade; dureza]. Não houve proteção do probiótico pelo prebiótico, ao nível de FOS utilizado neste estudo. Foram efetuadas análises sensoriais de preferência pareada para o cheesecake (em três tratamentos: T0, T1 e T2) e para sua cor (em três amostras com curcumina a: 0%, 0,0076% e 0,0152%). O resultado para o cheesecake revelou que: a amostra mais preferida foi a T0; os tratamentos T1 e T2 não diferem entre si quanto à preferência; T0 não difere da T2; T0 difere da T1. O resultado para a cor do cheesecake revelou que: a amostra mais preferida foi a com curcumina a 0,0076%; e que as três amostras são iguais quanto à preferência da cor. O presente estudo dá sua contribuição para ampliar a oferta de alimentos láteos promotores da saúde humana com características: light, potencialmente funcional e simbiótico.The aim of this work was the development and the evaluation of the functionals, physical-chemistry, rheological and sensorial analysis for the pairwise ranking test (cheesecake and its color), and microbiological properties of the cheesecake manufactured with wheat flour (or modified waxy corn starch - AMCM), fresh cheese, sucrose, erythritol (as sucrose partial substitute), eggs in nature, butter [or frutooligosaccharide (FOS) - prebiotic - as butter fat replacer], curcumin and Bifidobacterium animalis subspecies lactis Bb-12 (probiotic). The statistical analysis of the data was considered the existence four experimental groups: [2 cheesecakes lights (in sucrose and fat) potentially functional and symbiote: T1= wheat flour and FOS; T2 = AMCM and FOS] and [2 cheesecake light (in sucrose) potentially functional and probiotic: T3 = wheat flour and butter; T4 = AMCM and butter]. It was established a treatment T0 as the standard Thesis, adapted the wording of QuarkTorte by Henning Fleissig (Germany). The response variables were type of quantitative, whereas colony forming units (CFU) of lactic bacteria, forming unit colonies (CFU) of total and faecal coliforms, pH, water activity, hardness, adhesiveness, elasticity, cohesiveness, gumminess, chewiness. These variables of responses comprised a model of Analysis of Variance with repeated measures, because the experimental units were observed after 1, 8, 15, 22 and 28 days. Measures (such as average, median and standard deviation), graphics and ANOVA, were generated by statistical package STATA® - version 9.0. The results of the ANOVA showed no statistically significant results that indicate differences between the experimental groups [p-value: 0,7981; 0,4204; 0,9974; 0,6825; 0,6401; 0,4800; 0,6469; 0,4258; 0,4615] and not between the values over time, within each experimental group [p-value: 0,1725; 0,0000; 0,4076; 0,8957; 0,8787; 0,0001; 0,6214; 0,8845; 0,6820] [p-value corresponding respectively to: log of UFC of lactic bacteria; pH; water activity (aw); chewiness, gumminess, cohesiveness, elasticity, adhesiveness and hardness]. There was no protection of probiotic by prebiotic, at the level of FOS used in this study. Were made sensorial analysis of paired preference for the cheesecake (In three treatments: T0, T1 and T2) and to its color (in three samples with curcumin: 0%, 0.0076% and 0.0152%). The result for the color of the cheesecake revealed that: the sample most preferred was with curcumin to 0.0076%; and that the three samples are equal as the color preference. The present study gives its contribution to extend the offer of lactic food human health promoters with characteristics: light, potentially functional and symbiote.
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Ricoldi, Milla Sprone Tavares. "Avaliação dos efeitos do probiótico Bifidobacterium animalis subsp. lactis HN019 como terapia adjuvante no tratamento da periodontite experimental em ratos". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/58/58138/tde-21052018-162023/.
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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° 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° 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.
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Oliveira, Daniela Lara Pedroso de. "Produção e avaliação de micropartículas lipídicas contendo Lactobacillus acidophilus ou Bifidobacterium lactis produzidas por spray chiling". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-17112011-101818/.
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Lactobacillus acidophilus e Bifidobacterium lactis são microrganismos probióticos frequentemente utilizados em alimentos funcionais. No entanto, estes microrganismos devem resistir ao processamento, à estocagem do alimento, e sobreviver à passagem pelo trato-gastrointestinal, para chegarem ativos ao intestino e exercerem seus efeitos benéficos. Uma vez que os probióticos são sensíveis a uma série de fatores, tais como meio ácido, sais biliares e presença de oxigênio, a microencapsulação tem sido estudada com objetivo de protegê-los aos efeitos adversos do ambiente, além de promover a liberação controlada no local de ação do microrganismo, melhorando sua eficiência. Este trabalho teve como objetivo a produção e avaliação de micropartículas lipídicas contendo B. lactis ou L. acidophilus, produzidas por spray chilling, utilizando gorduras de baixo ponto de fusão, tais como gordura de palma e manteiga de cacau, como agente encapsulante. O diâmetro médio e a morfologia das partículas foram avaliados. Ensaios de sobrevivência foram conduzidos com objetivo de avaliar a resistência dos microrganismos ao processo encapsulação, resistência in vitro aos fluidos gástrico e intestinal simulados e estabilidade das células durante 90 dias de armazenamento a -18, 7 e 20 ou 37°C, dependendo da gordura utilizada. As micropartículasapresentaram-se em formato esféricoe com diâmetro médio que pode permitir o fácil escoamento no alimento, sem proporcionar impacto tecnológico negativo.A tecnologia de encapsulação por spray chilling, utilizando gordura de palma e manteiga de cacau, como agentes encapsulantes, proporcionou a obtenção de micropartículas eficientes na proteção dos probióticos frente ao processo de encapsulação e na manutenção da estabilidade das células quando estocados sob congelamento. Entretanto, aeficiência das micropartículas frente aos fluidos gastrointestinais e a estabilidade das células quando estocadas a 7 e 20 ou 37°C variaram de acordo com a gordura utilizada e com o microrganismo encapsulado. As micropartículas lipídicas obtidas são, portanto, uma matriz inovadora para a aplicação de probióticos, de baixo custo e com grande possibilidade de obtenção em escala industrial. O desafio futuro para o presente estudo é a seleção de um agente encapsulante que aumente a estabilidade das células, nas temperaturas ambiente e de refrigeração, a fim de aumentar as possibilidades de aplicação destas microcápsulas em produtos alimentícios.L. acidophilus and Bifidobacterium lactis are probiotic microorganisms frequently used in food product. However they must remain viable during processing, entire shelf life of product and passing-through the gastrointestinal tract to provide beneficial effects on human health. Since theses microorganisms are sensitive to a series of factors, especially presence of oxygen and acid medium, microencapsulation has been studied as an alternative to increase probiotic cells viability and to provide the controlled release in the site of action, improving their efficiency. The aim of this study was to produce and evaluate lipid microparticles of L. acidophilus or B. lactis produced by spray chilling technology using low melting point fats, such as palm fat and cocoa butter, as the encapsulant agent. The mean diameter and morphology of the microparticles were evaluated. Survival assays were conducted to evaluate the resistance of the microorganisms to the spray chilling process, viability to the in vitro simulated gastric and intestinal fluids and viability during 90 days of storage at -18, 7 and 20/37°C, depending on the fat used. Microparticles presented a spherical shape and mean diameter that allows the flow of material in the food product without conferring technology influence. Spray chilling technology using fat palm or cocoa butter as the encapsulant agent was efficient in protecting the microorganism to the encapsulation process and 90 days of storage at -18°C. However the efficiency of the microparticles on the gastric and intestinal fluids and the cells stability during storage at 7 e 20 or 37°C varied according to the fat and microorganism used. The lipid microparticles seem to be a relatively innovative matrix for the application of probiotics with low costs and possibility of scale up. The future challenge in this study is to choose an encapsulant agent that improves cells resistance and viability at refrigerator and room temperatures to increase the possibility of application of these microcapsules in food products.
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Horb, Katharina [Verfasser]. "Einfluss von Bifidobacterium animalis subsp. lactis BB-12 auf die Kariogenität von Streptococcus mutans in vitro / Katharina Horb". Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2017. http://d-nb.info/1139254685/34.
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Prioult, Guénolée. "Développement d'une méthode en immunofluorescence pour la détection et la quantification de Bifidobacterium longum et Lactococcus lactis ssp. lactis biovar. diacetylactis coimmobilisés dans des billes de gel". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0007/MQ44942.pdf.
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Silva, Priscilla Diniz Lima da. "Desenvolvimento de sorvete probi?tico a base de leite de cabra: estudo da formula??o, caracter?sticas f?sico qu?micas, sensoriais e viabilidade das bact?rias probi?ticas". Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15907.
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This work targetet the caprine ice cream production added with probiotic bacteria Bifidobacterium animalis subsp. lactis. It is divided into two parts. In the first one, four caprine ice cream formulations were evaluated, in which it was used hydrogenated fat (F1 and F3) or fat substitute (F2 and F4) in two different flavors (F1 and F2, passion fruit, F3 and F4, guava). Statistical differences (p<0.05) were detected for their physical-chemical properties, mainly for total solids and fat, but no differences were observed for melting test results. When it went to sensory acceptance, all four ice cream formulations reached high acceptance indexes, mostly formulation F4, which was selected for further studies. In the second part, F4 formulation was prepared with the addition of probiotic bacteria Bifidobacterium animalis subsp. lactis. The growth kinetics was studied and it was observed that the cellular concentration peak was reached after four fermentation hours (10.14 log UFC/g). This time was selected for pre-fermentation procedure and posterior addition at ice cream syrup. In this part of the study, two experimental groups were evaluated: group G1, in which the probiotic addition occurred before the maturation step and group G2, which included a pre-fermentation step and probiotic addition after ice cream maturation. The physical-chemical properties of these two ice cream groups were similar, except for pH, which was higher for group G2 (p<0.05). G1 samples had superior melting rate (3.566 mL/min) and both groups presented microbiological and sanitary results in accordance to current Brazilian legislation. Also, G1 and G2 were considered sensory accepted due to their acceptance indexes higher than 70%. G1 and G2 sensory profiles were similar (p>0.05), and both ice cream samples exhibited high creaminess (6.76 to 6.91) and mouth melting sensation (6.53 to 6.67) scores, while low sandiness scores (0.85 to 0.86) were observed, positive characteristics for this kind of food product. During the first 24 hours after ice cream production, the population of B. animalis subsp. lactis decreased, reaching 7.15 e 6.92 log CFU/g for G1 and G2, respectively. Probiotic bacteria counts fluctuated in ice cream samples during the first 108 days at frozen storage, especially for G2 group. Decreased probiotic viability was observed for G1 samples during the first 35 days of frozen storage, mild variation between 35 and 63 days and stabilized counts were observed after this time. After 21 days at frozen storage, ice cream samples of G1 and G2 groups reached 1.2 x 109 and 1.3 x 109 CFU/portion, respectively. After 108 days under these storage conditions, the survival rate of B. animalis subsp. lactis was 94.26% and 81.10% for G1 and G2 samples, respectively. After simulation of gastroenteric conditions, G2 group reached 9.72 x 105 CFU/portion. Considering the current requirements of Brazilian legislation, which stipulates that functional foods must have minimum probiotic count between 108 and 109 CFU/portion and detectable probiotic bacteria after being submitted to gastroenteric conditions, it is concluded that the ice cream with the addition of Bifidobacterium animalis subsp. lactis made as shown in this work, can be considered as a dairy functional food
O presente trabalho teve o objetivo de estudar a produ??o de sorvete elaborado com leite caprino com adi??o da bact?ria probi?tica Bifidobacterium animalis subsp. lactis. Foi estruturado em duas etapas. Inicialmente foram avaliadas quatro formula??es de sorvete, nas quais foi utilizada gordura vegetal hidrogenada (F1 e F3) e substituto de gordura (F2 e F4) em dois sabores (F1 e F2, maracuj?; F3 e F4, goiaba). Os c?lculos de densidade aparente e overrun foram feitos levando em considera??o as especifica??es da RDC n?. 266 de setembro de 2005. Tamb?m foram realizadas determina??es de pH, acidez total titul?vel e s?lidos totais, s?lidos sol?veis e res?duo por incinera??o, m?todo Kjeldahl para determina??o de prote?na bruta, lip?dios, a??cares redutores e totais. Al?m destas an?lises foram realizados o teste de derretimento e as an?lises microbiol?gicas nos sorvetes elaborados. As formula??es apresentaram diferen?as significativas (p<0,05) quanto ? composi??o f?sico-qu?mica, sobretudo no que diz respeito ao teor de s?lidos totais e gordura, mas n?o foi observada influ?ncia da formula??o sobre o perfil de derretimento das amostras. Quanto ? avalia??o sensorial, as quatro formula??es apresentaram elevados ?ndices de aceita??o, sobretudo a formula??o F4. Essa formula??o foi selecionada para dar prosseguimento aos estudos, cujo objetivo foi estudar os procedimentos de elabora??o do sorvete de leite de cabra com adi??o de B. animalis subsp. lactis. O pico de concentra??o celular (10,14 log UFC/g) foi alcan?ado ap?s quatro horas de cultivo sendo esse ponto escolhido para o procedimento de pr?-fermenta??o e adi??o de B. animalis subsp. lactis na calda do sorvete. Foram avaliados dois grupos experimentais de sorvete caprino com adi??o de probi?ticos: o grupo G1, com adi??o das bifidobact?rias antes da matura??o e G2, com etapa de pr?-fermenta??o e adi??o ap?s a matura??o. As propriedades f?sico-qu?micas dos dois grupos foram similares, com exce??o do pH, cujo valor foi superior no grupo G2 (p<0,05). O grupo G1 apresentou maior (p<0,05) taxa de derretimento (3,566 mL/min) e ambos os tratamentos apresentaram padr?es microbiol?gicos e sanit?rios dentro do exigido pela legisla??o vigente. Os dois grupos foram considerados aceitos sensorialmente, por exibirem n?veis de aceita??o superiores a 70% em todos os atributos verificados. Os perfis sensoriais das amostras G1 e G2 foram semelhantes (p>0,05), com elevados escores para os atributos cremosidade (6,76 a 6,91) e derretimento na boca (6,53 a 6,67), al?m de pontua??o reduzida para o quesito arenosidade (0,85 a 0,86), resultados considerados positivos para esse tipo de alimento. Foi observado decr?scimo da popula??o de B. animalis subsp. lactis ap?s as primeiras 24 horas de produ??o com contagens de 7,15 e 6,92 log UFC/g para G1 e G2, respectivamente. A contagem de bact?rias probi?ticas apresentou varia??es ao longo do armazenamento congelado por 108 dias, sobretudo para o grupo G2. O grupo G1, por sua vez, apresentou queda de viabilidade durante os primeiros 35 dias de congelamento, leve varia??o entre 35 e 63 dias de armazenamento e tend?ncia ? estabiliza??o ap?s esse ponto. Ap?s 21 dias sob armazenamento congelado, as amostras G1 e G2 apresentaram contagem de 1,2 x 109 e 1,3 x 109 UFC/por??o, respectivamente, conforme determina a legisla??o para contagens m?nimas por por??o de comest?veis gelados. Por sua vez, ao final de 108 dias sob essas condi??es, as taxas de sobreviv?ncia do B. animalis subsp. lactis do grupo G1 e G2 foram respectivamente, 94,26% e 81,10%. Ap?s ser submetido a condi??es g?stricas e ent?ricas simuladas in vitro, o sorvete com quatro meses de armazenamento do tratamento G2 apresentou contagem 9,72 x 105 UFC/por??o. Considerando o disposto pela legisla??o nacional vigente, segundo a qual um alimento com alega??o funcional deve possuir contagem m?nima probi?tica entre 108 e 109 UFC/por??o e exist?ncia de microrganismos vi?veis ap?s exposi??o ?s condi??es gastroent?ricas, conclui-se que o sorvete com adi??o de B. animalis subsp. lactis, produzido no presente estudo, constitui alimento l?cteo funcional
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Alegro, João Henrique Alarcon. "Desenvolvimento de queijo Minas frescal probiótico com \'Lactobacillus acidophilus\' e \'Bidifobacterium lactis\' isolados e em co-cultura". Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/9/9133/tde-11092006-102044/.
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O interesse do consumidor por produtos alimentícios saudáveis e até capazes de prevenir doenças, como alimentos funcionais probióticos, tem aumentado visivelmente nos últimos anos. A possibilidade de se desenvolver produtos lácteos de grande aceitabilidade nacional como o queijo Minas frescal com microrganismos probióticos tem futuro promissor. O presente trabalho teve como objetivo verificar a influência do emprego de culturas probióticas compostas pelos microrganismos Lactobacillus acidophilus e Bifidobacterium lactis isolados e em co-cultura na tecnologia de fabricação de queijo Minas frescal sobre as características do produto ao longo de seu armazenamento refrigerado. Os queijos foram preparados com acidificação com ácido lático e 4 tratamentos (em quadruplicata) foram empregados para se avaliar a ação dos microrganismos probióticos: T1 (controle), T2 (adição de L. acidophilus), T3 (adição de B. lactis) e T4 (adição de L. acidophilus + B. lactis). Avaliou-se o comportamento de L. acidophilus, B. lactis, bactérias láticas totais, Staphylococcus spp., coliformes totais e E. coli. Paralelamente, foi feita a determinação do perfil de textura dos queijos através de teste de dupla compressão de amostras cilíndricas, em analisador de textura TA-XT2 (Stable Micro System) e determinação de umidade, pH, acidez titulável e atividade de água. As análises foram realizadas no dia de processamento (dia 1) e após 7, 14 e 21 dias de armazenamento a 5 C. As análises microbiológicas também foram realizadas no leite e no queijo em processamento. A comparação entre os queijos foi estudada também através de análise sensorial, empregando-se teste de aceitação/preferência. Os queijos T4 revelaram-se mais apropriados quanto à multiplicação das bactérias probióticas. Com relação a multiplicação de coliformes, Staphylococcus spp. e bactérias láticas totais, não foi observada diferença significativa (p>0,05) entre os tratamentos. Houve, porém, aumento significativo ao longo do armazenamento para Staphylococcus spp. nos queijos T3 e para coliformes totais nos queijos T1 (p<0,05). E. coli não foi detectado em nenhum dos queijos. A atividade de água não atuou como obstáculo no desenvolvimento de microrganismos, ficando sempre acima de 0,97 em todos os queijos. O pH e a acidez mostraram-se estatisticamente iguais (p>0,05) em todos os 4 queijos. Houve, porém, queda estatisticamente significativa do pH médio e aumento significativo da acidez (p<0,05) nos queijos T1 e T2. Nos parâmetros de textura, observou-se aumento significativo da dureza que é o parâmetro mais importante, na primeira semana para todos os queijos (p<0,05) e nas datas seguintes, tendência à estabilidade exceto para T3 que mostrou novos aumentos significativos (p<0,05) em 7 e 14 dias. A coesividade, a elasticidade e a adesividade mostraram-se estatisticamente iguais (p>0,05) em todas as datas de amostragem em todos os queijos. Na avaliação sensorial dos queijos, não foi observada aceitabilidade diferenciada para nenhum dos queijos. Concluiu-se que o queijo frescal probiótico tipo Minas frescal mostrou-se com propriedades sensoriais, de textura e microbiológicas adequadas e apropriado como veículo para L. acidophilus e B. lactis, porém com melhor desenvolvimento destes quando em co-cultura (T4), associado ao fato deste queijo ter se comportado da forma mais estável dentre os queijos estudados, quando avaliados todos os pontos de variação significativa ao longo do armazenamento.Functional foods consuming habits have been increasing over the years, particularly in the case of probiotic dairy food. The possibility of developing new probiotic dairy products, like the popular Brazilian Minas fresh cheese, is very promising. The objective of the present work was to verify the influence of the probiotic cultures containing Lactobacillus acidophilus and Bifidobacterium lactis, added individually and in co-culture during fresh Minas cheese production, over the microbiological, textural and physico-chemical behavior of the product during refrigerated storage. Four treatments were prepared (four times each), all of them were made through direct acidification with lactic acid: T1 (control), T2 (addition of L. acidophilus), T3 (addition of B. lactis) e T4 (addition of L. acidophilus + B. lactis). Microbiological counts of L. acidophilus, Bifidobacterium spp., total lactic acid bacteria (LAB), coliforms, Staphylococcus spp. and E. coli and analysis of pH, acidity, moisture content and water activity proceeded after 1, 7, 14 and 21 days of storage at 5 C. Microbiological analysis was also conducted in milk and during cheese manufacturing process. Additionally, texture properties of cheeses were evaluated during storage, employing a TA-XT2 Texture Analyser (Stable Micro Systems, Haslemere, England), using a two-bite compression of cylindrical samples. Parameters measured consisted of hardness, elasticity, cohesiveness, chewiness, gumminess and adhesiveness. Comparison of cheeses was also conducted through sensory evaluation after 7 days of storage, using Preference- Ranking test. Cheeses T4 revealed to be more appropriate for growth of both probiotic bacteria, maintaining populations of 6 log CFU/g or above. No significant differences (p>0.05) between treatments were observed in relation to coliforms, Staphylococcus spp. and LAB, though Staphylococcus spp. and coliforms increased significantly during storage of cheeses T3 and T1, respectively (p<0.05). E. coli was not detected in any of the cheese and milk samples. Water activity values stayed above 0.970 for all samples, therefore proper for microbial growth. Mean pH and acidity did not differ significantly among treatments (p>0.05). Nevertheless, cheeses T1 and T2 revealed a significant decrease in pH (6.2 to 5.9 and 6.7 to 6.1, respectively) and increase in acidity from day 1 to day 21 of storage (p<0.05). As for the texture profile of cheeses, a significant increase in hardness (p<0.05) was detected for all cheeses studied in the first week of storage, followed by a tendency for stability during the subsequent storage period, except for cheeses T3, for which a significant increase in hardness was also detected from day 7 to day 14 of storage. Cohesiveness, springiness and dhesiveness showed to be statistically equal (p>0.05) for all cheeses and for all sampling days. No significant differences were detected through sensory evaluation between the four kinds of cheeses studied (X0
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Costa, Renata Brum. "ESTUDO DA VIABILIDADE DE MICRORGANISMO PROBIÓTICO BIFIDOBACTERIUM LACTIS EM PATÊ DE FRANGO COM CARACTERÍSTICAS SIMBIÓTICAS E SUA AÇÃO NA ESTABILIZAÇÃO DA OXIDAÇÃO LIPÍDICA". Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/5733.
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The aim of this study was to investigate the viability of Bifidobacterium lactis microorganism as probiotic when applied to pate chicken storage for period of 42 days. The chicken pate was prepared in the laboratory of meat processing of the UFSM Polytechnic College, according to the formulation provided by local industry. A portion of this mass of pate was enriched with unripe banana flour (Musa spp.) constituting a symbiotic food. The culture used was probiotic strain Bifidobacterium lactis 420 (B420), acquired by Danisco do Brasil Ltda. Two different inoculants were made in order to reach the expected final concentration of Log 106 UFC.g-1 and 108 UFC.g-1. Preliminary tests of microorganism resistence at different temperatures in the chicken pate were performed in order to establish the best temperature for the inoculation. The strain of microorganism was tested against different concentrations of NaCl (1.0%, 1.5% and 2.0%) and NaNO2 (150 ppm, 200 ppm and 250 ppm). It was resistant to all tests, including when combined concentrations of these values, but it showing increased sensitivity with increasing concentration. The product developed was evaluated by physical-chemical properties ( proximate composition and TBARS), microbiologic (coliforms at 45ºC, Clostridium perfringens, Staphylococcus coagulase positive, Salmonella sp.) and sensory (color, aroma, flavor and texture). It was found that the product reached all the requirements established by Brazilian legislation regarding chemical composition and microbiological standards. Taking into account the previsions of Brazilian law that establishes the minimum amount of viable probiotic bacteria, in the product ready for consumption, is between 108 to 109 colony forming units, the Bifidobacterium lactis was considered a good probiotic for chicken pate for a period of 21 days only, period is too short considering the shelf-life of the traditional chicken pate, which can reach up to 90 days of refrigerated storage. The determination of lipid oxidation (TBARS) showed that treatments 2 and 3 with the addition of the probiotic microorganism in a concentration of 108 UFC.g-1 obtained more satisfactory results when compared to the control and treatment of an added 106.UFC.g-1 of the probiotic, suggesting that the probiotic microorganisms in certain concentrations have a positive influence on the oxidation of lipids in the chicken pate, putting a "protective effect". Treatments with Bifidobacterium lactis had a good sensory acceptance in attributes, with the exception of treatment 3, which was added unripe banana flour, which changed the color and texture of the product but also impaired the development of Bifidobacterium lactis . In this study, it was found that treatment with the addition of probiotic micro-organism concentration of 108 UFC.g-1 was the best satisfied the initial goals as far as the viability of the probiotic lipídica oxidation stabilization. Althoug of a shelf-life minor, it can be seen that there is the feasibility of the probiotic Bifidobacterium lactis organism in meat products such as cooked chicken pate, which has the acceptance by consumers and can serve as an alternative development of meat products with functional properties.O objetivo do presente trabalho foi estudar a viabilidade como probiótico do microrganismo Bifidobacterium lactis quando aplicado em patê de frango durante o período de armazenamento de 42 dias. O patê de frango foi elaborado no laboratório de processamento de carnes do Colégio Politécnico da UFSM, de acordo com a formulação fornecida pela indústria local. Uma parte dessa massa de patê foi enriquecida com farinha de banana verde (Musa spp.) constituindo um alimento simbiótico. A cultura utilizada foi a cepa probiótica Bifidobacterium lactis 420 (B420), adquirada através da Danisco do Brasil Ltda. Foram feitos dois inóculos diferentes visando atingir as concentrações finais de Log 106 UFC.g-1 e 108 UFC.g-1 . Testes preliminares de resistência do microrganismo a diferentes temperaturas no patê de frango foram realizados com o intuito de estabelecer a melhor temperatura para a inoculação. A linhagem do microrganismo foi testada frente à diferentes concentrações de NaCl ( 1% , 1,5 % e 2% ) e NaNO2 (150 ppm, 200 ppm, e 250 ppm) , sendo resistentes em todos os testes, inclusive quando em concentrações combinadas desses valores, porém demonstrando aumento da sensibilidade com o aumento da concentração. O patê de frango foi avaliado através de análises físico-químicas (composição centesimal e TBARS), microbiológicas (contagem de Bifidobacterium lactis, Coliformes a 45ºC, Clostridium perfringens, Staphylococcus coagulase positiva, Salmonella sp.) e sensoriais (cor, aroma, sabor e textura). Verificou-se que o produto atendeu os requisitos estabelecidos pela legislação brasileira quanto a composição centesimal e padrões microbiológicos. Levando em consideração os preceitos da legislação brasileira para alimentos funcionais que estabelece que a quantidade mínima de bactérias probióticas viáveis no produto pronto para consumo deve estar situada entre 108 a 109 Unidades Formadoras de Colônias (UFC), constatou-se que o Bifidobacterium lactis foi considerado com uma boa viabilidade como probiótico no patê de frango até o 21º dia de armazenamento, período muito curto. A determinação da oxidação lipídica (TBARS) mostrou que os tratamentos 2 e 3 com adição do microrganismo probiótico na concentração 108 UFC.g-1 obtiveram resultados mais satisfatórios quando comparados ao controle e o tratamento 1 adicionado de 106 UFC.g-1 do probiótico, sugerindo que os microrganismos probióticos em determinado nível de concentração apresentam uma influência positiva quanto à oxidação dos lipídios no patê de frango, exercendo um ―efeito protetor‖. Os tratamentos com Bifidobacterium lactis obtiveram uma boa aceitação sensorial nos atributos avaliados, com exceção do tratamento 3 , que foi adicionado de farinha de banana verde, a qual modificou a cor e a textura do produto como também prejudicou o desenvolvimento do Bifidobacterium lactis.. Neste estudo, verificou-se que o tratamento com adição do microrganismo probiótico na concentração de 108 UFC.g-1 foi o que melhor atendeu aos objetivos iniciais, tanto na viabilidade do probiótico como na estabilização da oxidação lipídica.Embora com um período de vida útil menor , pode-se observar que existe a viabilidade de aplicação do microrganismo probiótico Bifidobacterium lactis em produtos cárneos cozidos como o patê de frango, que possui aceitação pelo consumidor, podendo servir como alternativa no desenvolvimento de produtos cárneos com propriedades funcionais.
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Oliveira, Alessandra Cristina. "Viabilidade de \'Lactobacillus acidophilus e Bifidobacterium lactis\', microencapsulados por coacervação, seguida de secagem por \'spray drying\' e leite de jorro". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/60/60137/tde-10052007-103644/.
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No presente trabalho microcápsulas contendo B. lactis (BI 01) e L. acidophilus (LAC 4) foram produzidas por coacervação complexa, utilizando pectina e caseína como agente encapsulante e posteriormente foram desidratadas em spray dryer e leito de Jorro. Este estudo avaliou a resistência desses microrganismos aos processos de secagem, de estocagem (120 dias a 7 e 37°C) e a tolerância ?in vitro? quando inoculados em soluções de pHs ácidos (pH 1.0 e 3.0), além da morfologia das microcápsulas por Microscopia ótica e eletrônica de varredura. Após a secagem em spray dryer foi verificada a integridade celular da maioria da população, porém, L. acidophilus foi mais resistente às condições utilizadas do que B. lactis. A secagem em leito de jorro também foi promissora, uma vez que manteve a viabilidade celular da maioria da população de probióticos. L. acidophilus microencapsulados e secos por spray dryer mantiveram a viabilidade por um período de estocagem maior do que B. lactis. A vida útil do L. acidophilus microencapsulados e secos em leito de jorro é maior quando armazenado em temperaturas mais baixas (7° C). No entanto B. lactis microencapsulados e secos em leito de jorro perdem sua viabilidade durante o armazenamento em ambas as temperaturas (7 e 37° C). O resultado obtido no teste, que consistia em avaliar o efeito do pH sob Lactobacillus acidophilus e B. lactis, permitiu inferir que quando estes microrganismos microencapsulados foram secos por spray dryer se mostraram mais resistentes às condições ácidas do que os não encapsulados. Entretanto, as microcápsulas quando secas em leito de jorro, não foram eficientes para prover proteção aos L. acidophilus e B. lactis em pHs similares ao do estômago humano. A microscopia eletrônica de varredura confirmou que as partículas secas em spray dryer apresentaram formato esférico, sem presença de fissuras e as partículas secas em leito de jorro, formatos irregulares.In this present work, microcapsules containing B. lactis or L.acidophilis were produced by complex coacervation based on pectin and casein interactions. After coacervation the systems were dehydrated by spray drying or spouted bed techniques. In this present study could evaluate the resistance of these microorganisms to dehydration process, shelf life (storage at 7 and 37 ºC for 120 days), and their in vitro tolerance after being inoculated in acid solutions (pH 1.0 and 3.0). Moreover the morphology characteristics were analyzed by optical microscopic and scanning electron microscopic. Both systems maintained their cellular integrity after spray drying, although, L. acidophilus microcapsules were more resistant. Spouted bed drying was also promising, once the microorganism still remains viable. Comparing the results about shelf life, it is noticeable that L. acidophilus microcapsules dehydrated by spray dried maintained viability for storage period greater than B. lactis. When the microcapsules were dehydrated by spouted bed, the L. acidophilus obtained higher viability at 7ºC stored temperature. In contrast, B. lactis lose their viability during storage at both temperatures (7 and 37ºC).The in vitro studies showed that the microorganisms encapsulated, dehydrated by spray dried, were more resistance to acid pH conditions than free ones. Furthermore, microcapsules when dried in spouted bed were not efficient to provide protection to both microorganisms at this pH?s values. The scanning electron microscopic showed that the particles obtained by spray dryer were spherical without cracks, and the particles obtained by spouted bed presented irregular shape.
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Guerrero, Alva Dániza Mirtha. "Producción de leche fermentada utilizando bacterias probióticas (Lactobacillus acidophilus, Bifidobacterium lactis y Streptococcus thermophilus) con leche de cabra y vaca". Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2005. https://hdl.handle.net/20.500.12672/2103.
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En el presente estudio se adicionó un cultivo mixto Bio Rich constituido por Lactobacillus acidophilus La-1, Bifidobacterium lactis Bb-12 y Streptococcus thermophilus a leche de cabra, de vaca, así como a la mezcla de ambas en proporción (1:1); obteniéndose leche fermentada o cultivada entera o integral en base al contenido de acidez, porcentaje de grasa y al crecimiento de las bacterias probióticas Lactobacillus acidophilus (107ufc/ml) y Bifidobacterium lactis (106ufc/ml) además de Streptococcus thermophilus (109ufc/ml); las que cumplen las normas microbiológicas de las leches fermentadas o cultivadas.
Se determinó los siguientes parámetros de proceso: adición de cultivo Bio Rich (1% en leche de cabra y en la mezcla de leche de cabra y de vaca en partes iguales, y temperatura de proceso de 42º C; 2% en leche de vaca con temperatura de proceso de 39º C), pH de corte de 4,5.
El tiempo de proceso con leche de vaca, de cabra y con la mezcla de leche de cabra y de vaca (1:1) fue de 4 horas, 7 horas y 4 horas respectivamente.
Palabras clave: leche de cabra y de vaca, proceso.In the present study was added Bio Rich culture (composed by Lactobacillus acidophilus, Bifidobacterium lactis and Streptococcus thermophilus) to goat and cow milk and a mix of goat and cow milk (1:1). It was gotten whole fermented milk with good acidity, fat percentage, and enough probiotic bacteria’s growth (Lactobacillus acidophilus 107 cfu/ml, Bifidobacterium lactis 106 cfu/ml), besides Streptococcus thermophilus 109 cfu/ml. All of the fermented milks agreed with the safety food norms. The parameters of the process were: added culture (1% in goat and in cow and goat mix milk, fermentation temperature 42º C; 2% in cow milk and fermentation temperature 39º C); final pH of 4,5. The time of process with cow, goat, and cow and goat mix milk was: 4 hours, 7 hours and 4 hours respectively. Keywords: goat and cow milk, process.
Tesis
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Barbosa, Ilsa Cunha. "Desenvolvimento de queijo cremoso caprino com potencial simbiótico". Universidade Federal da Paraíba, 2016. http://tede.biblioteca.ufpb.br:8080/handle/tede/8596.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Probiotic cultures are described as single species or multiple species of microorganisms that when used for animals or man in appropriate amounts provide health benefits by promoting improvement in characteristics of the natural intestinal microflora. Prebiotics are non-digestible food components that reach the colon and selectively stimulate the proliferation or activity of populations of bacteria present there. A food classified as symbiotic constitutes one in which probiotics and prebiotics are combined in pre-established adequate amounts. This study was prepared creamy goat cheese with symbiotic potential, and evaluated the effects of the incorporation of probiotics Lactobacillus acidophilus LA-05 and Bifidobacterium lactis BB-12 and the prebiotic inulin on technological parameters, physico-chemical, microbiological and sensory product with 7 and 21 days of refrigerated storage (7 ± 1 ° C). Three were prepared cream cheese treatments goat with symbiotic potential: with 8 g / 100 g of inulin and Lactobacillus acidophilus (QLA); 8 g / 100 g of inulin and Bifidobacterium lactis (QBB); 8g / 100g inulin, L. acidophilus LA-05 and B. lactis BB-12 (QLB) co-culture plus cheese control (QC) added only the starter strain Lactococcus lactis subsp. cremoris and Lactococcus lactis subsp. lactis. The formulation of cheeses made allowed the preparation and filing with the INPI of an application for patent entitled "Cream cheese functional Goat milk and procurement process." L. counts acidophilus LA-05 and B. lactis BB-12 were greater than 6 log CFU / g, while the quantity of insulin was greater than 6 g / 100 g in cheese symbiotic with 7 and 21 days of storage. The firm reduced the synbiotic cheeses providing improved consistency of cream cheese. The evaluated cheeses showed high brightness values (L *), with a predominance of yellow (b *). QC showed a higher protein content, lipids and minerals compared to the others. A decrease of short-chain fatty acids and an increase of medium chain and long chain synbiotics in cheese compared to QC. There was an increase in the amount of linoleic acid conjugate in QLA, QBB and QLB. The highest values for depth of proteolysis, as well as the biggest changes in the release of free amino acids were found in QLB. The addition of inulin and probiotics did not affect the acceptance of the product. Inulin, L. acidophilus and B. lactis may be used together for production of synbiotic creamy goat cheese without detrimental effect on the general characteristics of the product quality associated with adding value to their functional potential
Os probióticos são descritos como culturas de uma única espécie ou de várias espécies de micro-organismos que quando utilizadas por animais ou pelo homem em quantidades adequadas trazem benefícios à saúde, promovendo melhora nas características da microflora intestinal natural. Os prebióticos são componentes alimentares não digeríveis que alcançam o cólon e estimulam seletivamente a proliferação ou atividade de populações de bactérias desejáveis nesse local. Um alimento classificado como simbiótico constitui-se aquele em que um probiótico e um prebiótico estão combinados em quantidades adequadas pré-estabelecidas. Neste estudo foi elaborado queijo caprino cremoso com potencial simbiótico, sendo avaliados os efeitos da incorporação dos probióticos Lactobacillus acidophilus LA-05 e Bifidobacterium lactis BB-12 e do prebiótico inulina sobre os parâmetros tecnológicos, físico-químicos, microbiológicos e sensoriais do produto, com 7 e 21 dias de armazenamento refrigerado (7±1ºC). Foram elaborados três tratamentos de queijo cremoso de leite de cabra com potencial simbiótico: com 8g/100g de inulina e Lactobacillus acidophilus (QLA); 8g/100g de inulina e Bifidobacterium lactis (QBB); 8g/100g de inulina, L. acidophilus LA-05 e B. lactis BB-12 (QLB) em co-cultura, além do queijo controle (QC) adicionado apenas da cepa starter Lactococcus lactis subsp. cremoris e lactis. A formulação dos queijos elaborados permitiu a elaboração e depósito no INPI de um pedido de patente de invenção intitulado “Queijo cremoso de Leite de cabra funcional e processo de obtenção”. As contagens de L. acidophilus LA-05 e B. lactis BB-12 foram maiores que 6 log UFC/g, enquanto que a quantidade de inulina foi maior que 6 g/100 g nos queijos simbióticos com 7 e 21 dias de armazenamento. A firmeza reduziu nos queijos simbióticos proporcionando melhora na consistência do queijo cremoso. Os queijos avaliados apresentaram elevados valores de luminosidade (L*), com predominância do amarelo (b*). O QC apresentou maior teor de proteína, lipídios e minerais comparado aos demais. Houve diminuição dos ácidos graxos de cadeia curta e aumento dos de cadeia média e de cadeia longa nos queijos simbióticos em relação ao QC. Observou-se aumento no teor de ácido linoleico conjugado em QLA, QBB e QLB. Os maiores valores para profundidade de proteólise, bem como as maiores mudanças na liberação de aminoácidos livres foram verificados em QLB. A adição de inulina e probióticos não afetou a aceitação sensorial do produto. A inulina, L. acidophilus e B. lactis podem ser utilizados em conjunto para a produção de queijo caprino cremoso simbiótico sem efeito negativo sobre as características gerais de qualidade do produto com agregação de valor associada ao seu potencial funcional.
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Doleyres, Yann. "Production en continu de ferments lactiques probiotiques par la technologie des cellules immobilisées". Thesis, Université Laval, 2003. http://www.theses.ulaval.ca/2003/20742/20742.pdf.
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Pour produire des ferments lactiques contenant des bifidobactéries par des cellules immobilisées, des fermentations ont été réalisées avec une culture pure de bifidobactéries ou en culture mixte avec une souche de lactocoques. Une méthode a été développée pour localiser et quantifier par immunofluorescence les deux souches dans des billes de gel. L’utilisation de cette méthode a permis d’observer une croissance bactérienne préférentielle à la périphérie des billes. La production continue de culture mixte a été étudiée avec un système composé d’un premier réacteur (R1) contenant les deux souches immobilisées séparément dans des billes de gel et d’un second réacteur (R2) opéré avec les cellules libres relarguées de R1. Une culture mixte concentrée de composition stable a été produite à 35°C dans l’effluent de R2. La redistribution des souches dans les billes fut observée en microscopie confocale. La résistance à différents stress des cellules libres produites dans l’effluent des deux réacteurs a augmenté avec le temps de fermentation.
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Al-Haj, Omar Amin. "The effect of casein hydrolysate formed by trypsin or bifidobacterium animalis subsp. lactis (Bb-12) culture on cholesterol and angiotensin converting enzyme (ACE) inhibition". Thesis, Cardiff Metropolitan University, 2008. http://hdl.handle.net/10369/6353.
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The hypocholesterolemic effect of peptides present in crude casein hydrolysate using trypsin from Bifidobacterium animalis subsp. lactis (Bb-12) culture grown in casein solution or in MRS broth were compared with the control (unhydrolysed crude casein). These samples have shown to reduce cholesterol level in vitro to varying degree between 24-87%. The unhydrolysed crude casein (control) has shown not to have a reducing effect on cholesterol level. The reduction level of cholesterol was found to be dependant on the degree of hydrolysis. Fractions obtained after size exclusion from crude casein hydrolysate formed by trypsin after 48h hydrolysis have shown to reduce cholesterol level to degree vary between 2.7% to 50%. Bb-12 or trypsin crude casein hydrolysates were also found to possess angiotensin-converting enzyme (ACE) inhibitory activity in vitro to a varying degree between 29% and 38%, respectively. Unhydrolysed crude casein showed no real effect on ACE inhibitory activity. Trypsin hydrolysate has slightly more effect on ACE activity than Bb-l2. A relationship was also found between ACE-inhibitory activity and degree of hydrolysis. Fractions of crude casein hydrolysate after 48h hydrolysis with trypsin by size exclusion have shown to have ACE-inhibitory activity varying between 37% and 50%. Several identified ACE-inhibitory peptides from active fractions were found to have Phe, Trp, Tyr, Arg, Lys or Pro at their ultimate C-terminal position, making them a possible candidate for ACE-inhibitory activity. Further analysis on the profiles of casein and whey protein fractions, obtained by fast protein liquid chromatography (FPLC), of skimmed milk and four different commercial types of probiotic health drinks, and casein profile of added Bb-12 culture were investigated to study the possible effect of probiotics on milk proteins. Differences in protein-profile were found between the control and the four commercial probiotic health drinks as well as with added Bb-12 culture. Whey proteins were more resistance to hydrolysis than caseins.
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Trindade, Carmen Silvia Favaro. "Encapsulação de Lactobacillus acidophilus (La-05) e Bifidobacterium lactis (Bb-12) e avaliação "in vitro", do nivel de tolerancia dos mesmos as secreções gastrintestinais". [s.n.], 2001. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255970.
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Orientador: Carlos Raimundo Ferreira GrossoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Esse trabalho visou a encapsulação de Lactobacillus acidophilus e Bifidobacterium lactis e a avaliação "in vitro" da tolerância desses microrganismos livres e encapsulados quando inoculados em soluções biliares e de pHs ácidos, ou seja, em condições semelhantes às encontradas no intestino e no estômago humano, respectivamente. Além disso, foi determinada a estabilidade de B. lactis livres e encapsulados, incorporados em iogurte que foi mantido sob refrigeração, durante 28 dias. Para tanto, foram utilizados como agentes encapsulantes os polímeros entéricos aceto fitalato de celulose e alginato e os métodos de microencapsulação por spray drying e de imobilização por extrusão, respectivamente. Lactobacillus acidophilus e Bifidobacterium lactis foram extremamente resistentes às soluções biliares, tanto livres, quanto encapsulados. Apresentaram boa resistência quando inoculados em soluções de pH 2. Entretanto, nas soluções de pH 1, as populações das células livres e imobilizadas em alginato foram dizimadas, enquanto as células microencapsuladas em aceto fitalato de celulose apresentaram uma maior resistência. B. lactis não apresentaram uma boa viabilidade em iogurte, em nenhuma das condições testadas. Foi possível encapsular Lactobacillus acidophilus e Bifidobacterium lactis pelos métodos de extrusão e por spray drying mantendo um número elevado de células viáveis. A imobilização em alginato de sódio não foi eficaz na proteção às células de Lactobacillus acidophilus e Bifidobacterium lactis e a microencapsulação em aceto fitalato de celulose foi efetiva na proteção dos mesmos inoculados em soluções ácidas, embora não tenha sido eficiente quando B. lactis microencapsulado foi inoculado em iogurte.
Abstract: This study aimed at encapsulating Lactobacillus acidophilus and Bifidobacterium lactis and at carrying out an "in vitro" studyof the tolerance of these microorganisms, both free and encapsulated, when inoculated into bile solutions and acid pH solutions, that is, into conditions similar to those encountered in the human intestine and stomach respectively. In addition, the stability of free and encapsulated B. lactis was determined, when inoculated into yoghurt and stored under refrigeration for 28 days. The encapsulating agents used for this purpose were the enteric polymers cellulose acetate phthalate and alginate, and the methods of microencapsulation were spray drying and immobilisation by extrusion, respectively. Lactobacillus acidophilus and Bifidobacterium lactis were extremely resistant to bile solutions, both in the free forms and encapsulated. They also presented good resistance when inoculated into solutions at pH 2.0. However at pH 1.0, both the free cells and those encapsulated in alginate were destroyed, whilst those encapsulated in cellulose acetate phthalate showed greater resistance. B. lactis showed poor viability in yoghurt, under ali conditions tested. It was possible to encapsulate Lactobacillus acidophilus and Bifidobacterium lactis by both the methods of extrusion and by spray drying, retaining an elevated number of viable cells. Immobilisation in sodium alginate was not efficient in protecting cells of Lactobacillus acidophilus and Bifidobacterium lactis, and microencapsulation was efficient in protecting these same organisms when inoculated into acid solutions, although it was not efficient when microencapsulated B. lactis was incorporated into yoghurt.
Doutorado
Doutor em Tecnologia de Alimentos
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Meléndez, Illanes Lorena. "Análisis de la evidencia científica que sustenta la utilización de reclamos de salud presentes en la publicidad de alimentos de dos productos que contienen Lactobacillus cassei y Bifidobacterium lactis". Doctoral thesis, Universidad de Alicante, 2015. http://hdl.handle.net/10045/50425.
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Objetivo: Analizar la utilización de alegaciones a la salud en la publicidad de lácteos probióticos que contienen Lactobacillus cassei y Bifidobacterium lactis. Metodología: Publicaciones 1, 2 y 3: Se analizó la situación actual en la utilización de alegaciones a la salud que utilizan la industria en la publicidad de alimentos, tanto a nivel legislativo como de evidencia científica existente, para la posterior publicación de tres editoriales en revistas científicas. Publicación 4: Se realizó una revisión sistemática de los ensayos clínicos (ECs) en los cuales se midiera sólo el efecto de Actimel® y Activia®, en población sana y cuyo objetivo correspondiera con la apelación a la salud que se le realiza al producto en su publicidad. Se evaluaron los niveles de evidencia y fuerza de recomendación. También se evaluaron los outcomes de los estudios publicados en la página web que no estaban dentro de la búsqueda. Resultados: Publicaciones 1, 2 y 3: Observamos que la creciente preocupación por la Salud y vida saludable han potenciado la venta de alimentos dietéticos y funcionales, esto ha generado una gran oportunidad de negocio a las empresas de alimentación que están posicionando el concepto “salud” con éxito de ventas. A su vez, existe hoy una reglamentación con el objetivo claro de evitar que los mensajes publicitarios exageren los beneficios de un alimento, pero se observa aún, un vacío a la hora de entregar información al consumidor por medio de la publicidad. Publicación 4: Cumplían con los criterios de inclusión 16 de los 440 artículos identificados. Sólo cuatro (25%) muestran evidencia recomendable con nivel 1b y grado de recomendación A y todos corresponden a Activia®. Sólo doce de los dieciséis estudios coinciden con los publicados en la página web corporativa. Conclusiones: Creemos que en una pieza publicitaria caracterizada por su brevedad, el consumidor apenas puede informarse de la realidad de las ventajas saludables del consumo del producto, con el agravante de una comunicación publicitaria que en muchos casos es demasiado concisa y poco clara, pudiendo llegar a confundir al consumidor sobre el aporte que para su salud puede tener el consumo o, peor aún, crearle unas expectativas que nunca llegarán a cumplirse. Las apelaciones a la salud utilizadas por Danone no poseen suficiente evidencia científica que las avale, especialmente en el caso de Actimel®. Además existe sesgo en su página web en que se publican artículos científicos que no tiene relación con las apelaciones que utilizan en publicidad evidenciando la necesidad de mejoras en la regulación de la publicidad de los probióticos, y un comportamiento más ético por parte de la empresa.
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Jedidi, Hajer. "Effet du stress gastro-intestinal sur la physiologie et le métabolisme des bactéries lactiques et probiotiques". Master's thesis, Université Laval, 2007. http://hdl.handle.net/20.500.11794/19234.
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Damin, Maria Regina. "Avaliação do efeito da suplementação do leite com hidrolisado de caseína, proteína concentrada de soro e leite em pó desnatado na produção de bioiogurtes fermentados por Lactobacillus bulgaricus, Lactobacillus acidophilus e Bifidobacterium lactis em co-cultura com Streptococcus thermophilus". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/9/9133/tde-11112016-112734/.
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As bactérias probióticas crescem lentamente em leite e a suplementação é um dos fatores que melhoram seu crescimento na produção de iogurtes funcionais ou bioiogurtes, além da aplicação em co-cultura com Streptococcus thermophilus. Desta forma, objetivou-se avaliar o efeito simultâneo da suplementação do leite com hidrolisado de caseína, proteína concentrada de soro e leite em pó desnatado na produção de bioiogurtes fermentados por Lactobacillus bulgaricus, Lactobacillus Acidophilus e Bifidobacterium lactis em co-culturas com Streptococcus thermophilus. A metodologia de superfície de resposta com delineamento de mistura foi empregada e diferentes composições de misturas de suplementação otimizadas foram obtidas para as diferentes co-culturas. Foi possível avaliar o efeito da suplementação simultânea do enriquecimento do leite com os três ingredientes estudados, identificar interação ocorrida entre os ingredientes e obter composições de mistura otimizadas. A co-cultura S. thermophilus e L. acidophilus obteve bons modelos preditivos e falta de ajuste não significativo para os parâmetros cinéticos tempo para se atingir pH 5,0 e 4,5 (tpH5,0 e tpH4,5). Ensaios de validação do modelo confirmaram a qualidade do ajuste. A otimização resultou composição de mistura da suplementação do leite com 50% de hidrolisado de caseína, 0% de proteína concentrada de soro e 50% de leite em pó, atende em 95% os critérios de desejabilidade. Os perfis de acidificação de culturas puras e co-culturas de Streptococcus thermophilus com Lactobacillus acidophilus em leite controle e leite suplementado no ponto ótimo foram estudados, assim como o comportamento dos bioiogurtes, usando-se a co-cultura, durante estudo de estabilidade ao armazenamento. Os parâmetros avaliados foram perda de viabilidade das bactérias, pós-acidificação e propriedades de textura. A microestrutura dos bioiogurtes obtidos com leite controle e suplementado no ponto ótimo foi analisada. Em todos os ensaios os bioiogurtes obtidos puderam ser considerados probióticos, pois as populações foram superiores ao mínimo recomendado para promoção de efeitos benéficos à saúde. O bioiogurte suplementado no ponto ótimo resultou em tempo de fermentação 32% menor em relação ao controle fermentado pela co-cultura de S. Thermophilus e L. acidophilus. A contagem de S. thermophilus permaneceu estável e de L. acidophilus decresceu durante o período de estudo de estabilidade ao armazenamento, embora as populações tenham sido superiores ao recomendado para promoção de efeitos benéficos à saúde aos 28 dias de armazenamento. A firmeza, a tensão limite τ0, os módulos de armazenamento G\' e de perda G\" do leite otimizado foram superiores ao leite controle, enquanto a porcentagem de recuperação estrutural apresentou comportamento oposto. A análise das micrografias do leite ótimo e do controle mostrou maior percentual de poros de menor diâmetro para o primeiro, indicando uma estrutura mais densa.The probiotic bacteria develop slowly in milk and for probiotic yogurt production milk supplementation improves bacteria growth. Beyond that, use of probiotic in combination with Streptococcus thermophiles is common and recommendable. The aim of this research was to evaluate the simultaneous effect of milk supplementation with casein hydrolysate, whey protein concentrate and skim milk powder in the production of bioyogurt. Milk was fermented by Lactobacillus bulgaricus, Lactobacillus acidophilus and Bifídobacterium lactis in co-cultures with Streptococcus thermophiles. The Response Surface Methodology for mixture model was applied and compositions of optimized mixtures for supplementation had been obtained. It was possible to evaluate the effect of the simultaneous supplementation, identify interaction between the ingredients and get optimized compositions of mixture. Mathematical models with lack of fit not significant were obtained and validation experiments confirmed the quality of the adjustment. For co-culture S. thermophiles and L. acidophilus the models were obtained for kinetic parameters time to reach pH 5,0 and 4,5 (tpH5,0 and tpH4,5). The optimization resulted in mixture composition with 50% of casein hydrolysate of casein, 0% of whey protein concentrate and 50% of skim milk powder, with fit the desirability in 95%.The acidifying profiles of pure cultures and co-culture of Streptococcus thermophiles and Lactobacillus acidophilus in milk prepared with the optimum ingredients amounts calculated by RSM and control milk were studied. Stability and bacterial viability during 28 days of cold storage for bioyogurts produced with optimum and control milk had been studied, using co-culture of S. thermophiles and L. acidophilus. The loss of viability of bacteria, post-acidification and texture properties were examined. The microstructure of the two bioyogurts has been analyzed. All produced bioyogurts could have been considered probiotics, as the populations were higher than the minimum recommended one for promotion of beneficial effect to the health. Bioyogurt from milk supplemented at optimum region resulted in 32% of reduction on time necessary to reach pH 4.5, in comparison with that produced from control milk. The S. thermophiles counting remained stable, while L. acidophilus counts decreased, even so the populations were . superior to 1 billion at 28 days of storage. The firmness, yield stress τ0 , elastic G\' and viscous G\" modulus of optimum milk were superior to control milk during the study, while the structural recovery presented opposite behavior. The analysis of the micrographs of optimum milk and the control showed greater number of pores with small diameter for the former, indicating a denser structure.
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Stievenard, Sylvain. "Hydrolyse industrielle du lactose : mise au point au stade laboratoire d'un réacteur à lactase immobilisée". Lille 1, 1986. http://www.theses.fr/1986LIL10172.
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L'existence d'une activité lactasique chez un micro-organisme non pathogène nous a conduit à envisager la mise au point d'un procédé d'hydrolyse industrielle du lactose contenu dans le lait et les lactosérums. Notre démarche s'est appuyée sur plusieurs points : le procédé doit être facile à mettre en oeuvre industirellement et doit pouvoir se réaliser en continu. Il doit être en outre peu coûteux et conforme à la législation. La purification de la lactase est procédé qui s'est révélé être trop onéreux et déstabilisateur de l'activité enzymatique. Les cellules de ce microorganisme ont été incluses à l'intérieur d'un polymère d'origine naturelle. Nous avons comparé les paramétres enzymatiques de l'enzyme "libre" et "immobilisée". Le procédé mis au point au laboratoire est décrit, ses performances sont comparées à celles des autres systèmes existant déjà sur le marché.
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Hung, Ming-Ni 1962. "Biochemical and genomic analysis of -galactosidases from Bifidobacterium infantis HL96". Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36953.
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Among 29 strains of bifidobacteria studied as sources of beta-galactosidase enzyme, Bifidobacterium infantis HL96 showed the highest hydrolytic and transgalactosylic activities. This strain grew well in a MRS medium containing various sugars including lactose, and produced three beta-galactosidases (termed beta-Gal I, II, III).Two genes, beta-galI and beta-galIII, located on 4.6 and 4.4 kb DNA fragments respectively, were cloned into E. coli, and the nucleotide sequences were determined. The 3,069 by-long beta-galI, encoded a polypeptide with a Mr of 113 kDa. A putative ribosome-binding site and a promoter sequence were recognized at the 5' flanking region of beta-galI. A partial sequence of an ORF transcribing divergently from beta-galI resembled a lactose permease gene. The beta-galIII gene, which is 2,076 bp long, encoded a polypeptide with a Mr of 76 kDa. A rho-independent, transcription terminator-like sequence was found 25 bp downstream of the termination codon.
The amino acid sequences of beta-GalI and beta-GalIII were homologous to those in the LacZ and LacG families, respectively. The acid-base, nucleophilic, and substrate recognition sites conserved in the LacZ family were found in beta-GalI, and a possible acid-base site proposed for the LacG family was located in beta-GalIII, containing a glutamate at residue 160. beta-GalI and beta-GalIII were over-expressed 35 and 96 times respectively in E. coli by using a pET expression system.
Both beta-GalI and beta-GalIII were specific for beta-D -anomeric linked galactosides, but beta-GalI showed more hydrolytic and synthetic activities toward lactose than beta-GalIII. The galacto-oligosaccharides (GaOS) production mediated by beta-GalI at 37°C in 20% (w/v) lactose was 130 mg/ml, which is six times higher than that of beta-GalIII. The yield of GaOS further increased to 190 mg/ml in 30% (w/v) lactose. A major tri-saccharide produced by beta-GalI was characterized as O-beta- D-galactopyranosyl-(1-3)-O-beta-D-galactopyranosyl-(1-4)- D-glucopyranose.
beta-GalI was purified by ammonium sulphate precipitation, and anion-exchange (Mono-Q) and gel filtration (Superose 12) chromatographic steps. The enzyme appeared to be a tetramer, with a Mr of 470 kDa as estimated by native PAGE and gel-filtration chromatography. The optimum temperature and pH for ONPG and lactose as substrates were 60°C, pH 7.5, and 50°C, pH 7.5, respectively. The enzyme was stable over the pH range of 5~8.5, and was particularly active at 50°C for more than 80 min. The enzyme was significantly activated by reducing agents, especially glutathione, as well as by Na+ and K+ cations. Maximal activity required both Na+ and K+ at a concentration of 10 mM. The enzyme was strongly inhibited by p-chloromercuribenzoic acid, and by most bivalent metal ions. Hydrolytic activity using 20 mM lactose as substrate was significantly inhibited by 10 mM galactose. The Km and Vmax values for ONPG and lactose were 2.6 mM, 262 U/mg, and 73.8 mM, 1.28 U/mg, respectively.
The objectives of this research were to characterize beta-galactosidases of B. infantis HL96 at the molecular and biochemical levels, and to over-express the enzymes in Escherichia coli. Two beta-galactosidase isoenzymes with unique properties were genetically characterized for the first time. beta-GalI properties included a neutral pH optimum, relatively higher temperature stability and a high transgalactosylic activity that makes it very competitive for GaOS synthesis. The results were also important for the advancement of knowledge on the catalytic mechanism and the evolutionary aspect of this enzyme.
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Yamazaki, Shinichi. "Bioelectrochemical analysis on quinone-induced modification of the metabolism in bifidobacteria and lactic acid bacteria". Kyoto University, 2002. http://hdl.handle.net/2433/149899.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第9608号
農博第1236号
新制||農||841(附属図書館)
学位論文||H14||N3640(農学部図書室)
UT51-2002-G366
京都大学大学院農学研究科応用生命科学専攻
(主査)教授 池田 篤治, 教授 清水 昌, 教授 加藤 暢夫
学位規則第4条第1項該当
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Lima, Katia Gianni de Carvalho. "Otimização das condições de cultivo laboratorial de bactérias láticas e probióticas e avaliação do comportamento de Lactobacillus casei no trato gastrintestinal através de modelos simulados in vitro". Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-14102016-181423/.
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Os efeitos benéficos que as bactérias probióticas proporcionam à saúde humana dependem de sua quantidade e atividade biológica no intestino humano. Esse trabalho objetivou estabelecer as melhores condições laboratoriais para o cultivo e enumeração diferencial de cinco culturas de bactérias, sendo três probióticas (Bifidobacterium animalis Bb12, Lactobacillus acidophilus La05, Lactobacillus casei Lc01) e duas láticas não probióticas (Lactobacillus delbrueckii subsp. bulgaricus e Streptococcus thermophilus). O trabalho objetivou também avaliar a capacidade de duas linhagens de bactérias probióticas de Lactobacillus casei (Shirota e Lc01) sobreviverem ao transito pelo trato gastrintestinal humano (TGI), empregando modelos simulados in vitro. Foram testados vinte e um meios de cultura diferentes, semeados em superfície e em profundidade, e incubados a 37°C e a 42°C, em condições de aerobiose e anaerobiose. Para a avaliação da resistência ao TGI, empregou-se modelos simulados constituídos de solução de NaCI estéril (0,5% p/v) contendo pepsina (3g/L), com pH 1,5, 2,0, 2,5 e 3,0 (suco gástrico) e solução de NaCI estéril (0,5% p/v) contendo pancreatina (1g/L) e bile (10g/L), com pH 8,0 (suco entérico). As culturas foram expostas ao suco gástrico por até 120min, e em seguida ao suco entérico por até 240min. Os resultados indicaram que a suplementação do ágar MRS com diferentes compostos e o uso de combinações apropriadas de forma de semeadura e condições de incubação permitem tornar o ágar MRS um meio seletivo e diferencial para as diferentes espécies testadas. Em função dos resultados da avaliação dos meios de cultura, selecionou-se o ágar MRS pH 5,4 com semeadura em profundidade e incubação a 37°C em aerobiose para avaliar a resistência de L. casei (Shirota e Lc01) ao TGI. Os resultados revelaram que, após a exposição por 30min ao suco gástrico com pH 1,5 e 2,0, as duas linhagens de L. casei não eram mais cultiváveis. Em pH 2,5, houve redução de 4 ciclos log após 2h e, em pH 3,0, não houve modificação no número de células viáveis. A transferência para o suco entérico resultou na reversão parcial da injúria causada pelo suco gástrico extremamente ácido. Além disso, foi demonstrado que o leite pode proteger as bactérias do estresse decorrente da passagem pelo TGI.The beneficial effects of probiotic bacteria to the human health depend on their quantity and biological activity in the human gut. This study aimed to establish the best laboratorial conditions for the differential cultivation and enumeration of five bacterial cultures, including three probiotic (Bifidobacterium animalis Bb12, Lactobacillus acidophilus La05 and Lactobacillus casei Lc01) and two nonprobiotic (Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus) strains. In addition, this study also aimed to evaluate the capability of two probiotic strains (Lactobacillus casei Shirota and Lc01) to survive the transit through the human gastrointestinal tract, using in vitro simulated models. Twenty one different culture media were tested. They were inoculated using pour-plating and spread-plating techniques. Plates were incubated at 37°C and 42°C, under aerobiosis and anaerobiosis. Resistance to the gastrointestinal tract was tested using simulated models, constituted by 0.5% saline containing pepsin (3g/L) at pH 1.5, 2.0, 2.5 and 3.0 (gastric juice) and by 0.5% saline containing pancreatin (1g/L) and bile (10g/L) at pH 8.0 (enteric juice). The cultures were exposed to gastric juice (up to 120min) and then to enteric juice (up to 240min). Results indicated that supplementation of MRS agar with certain compounds and use of appropriate combinations of plating procedures and incubation conditions can turn MRS agar a selective and differential medium for the tested species. The combination MRS agar at pH 5,4, pour-plating and incubation at 37°C under aerobiosis was selected for evaluation of resistance of the L. casei (Shirota e Lc01) to the gastrointestinal tract. Results indicated that both cultures became non-culturable after 30min exposure to the gastric juice at pH 1.5 and 2.0. After 2h at pH 2.5, a 4 log reduction was observed. At pH 3.0, no change in the number of viable cells was detected. The subsequent transfer to the enteric juice caused a partial reversion in injury induced by the acid pH. In addition, it was observed that milk can protect the probiotic bacteria from the stress caused by the transit through the gastrointestinal tract.
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Watterlot, Laurie. "Analyse des effets de souches probiotiques anti-inflammatoires". Phd thesis, AgroParisTech, 2010. http://pastel.archives-ouvertes.fr/pastel-00570505.
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Les maladies inflammatoires chroniques de l'intestin sont caractérisées par une inflammation anormale et récurrente du tractus digestif. De nombreuses études ont démontré des effets bénéfiques de souches probiotiques anti-inflammatoires recombinantes ou non. La première partie de cette thèse décrit différentes stratégies d'optimisation de souches de bactéries lactiques en tant que vecteurs de protéines d'intérêt santé. Nous avons ainsi démontré qu'une modification du peptidoglycane de la paroie de Lactococcus lactis influençant la lyse bactérienne ne permettait pas de moduler l'immunogénicité de l'antigène E7 délivré par L. lactis. Nous avons également démontré que la nature du vecteur bactérien était un paramètre essentiel dans la vectorisation de la protéine délivrée : ainsi l'espèce Bifidobacterium infantis induit une réponse immunitaire spécifique à l'antigène E7 supérieure à celle obtenue avec les vecteurs L. lactis et Lactobacillus plantarum. La deuxième partie de cette thèse porte sur l'étude des effets anti-inflammatoires de bactéries recombinantes ou non. Nous avons ainsi démontré que la souche Lb. casei BL23 produisant une superoxyde dismutase à manganèse permettait de diminuer significativement des colites murines induites par administration de dextran sodium sulfate. Enfin, nous avons mis en évidence des propriétés anti-inflammatoires sur divers modèles d'inflammation in vitro / in vivo de Faecalibacterium prausnitzii, première bactérie commensale anti-inflammatoire identifiée sur la base de données cliniques humaines.
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Barreto, Gisela Pizarro de Mattos. "Avaliação de meios de cultura para quantificação de lactobacilos e bifidobacterias e contagem destes microrganismos em produtos lacteos". [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256177.
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Orientador: Edir Nepomuceno da SilvaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-03T09:30:43Z (GMT). No. of bitstreams: 1 Barreto_GiselaPizarrodeMattos_M.pdf: 25533381 bytes, checksum: e84ba6aa84229a0b693c3922f10e2044 (MD5) Previous issue date: 2003
Resumo: Neste trabalho foi realizado um estudo sobre o comportamento de diferentes cepas de bactérias lácticas ( por exemplo: Lactobacillus acidophilus, L.casei, L. lactis, L. delbruekii subsp. bulgaricus, Streptococcus thermophilus) e de bifidobacterias, utilizando diferentes meios de cultura (MRS, MRS-maltose, MRSsalicina, HHD e LA), para avaliar a similaridade entre eles, a capacidade de recuperação de cada um e a capacidade de quantificar as diferentes cepas. Primeiramente verificamos o comportamento de cepas puras depois, de cepas em diferentes misturas e, por último, de cepas presentes em iogurte e leite fermentado comercializado no mercado brasileiro. Também foi realizado um estudo da viabilidade das bactérias lácticas, presentes em produtos lácticos, durante o armazenamento. De acordo com os resultados obtidos, os quatro meios de cultura se mostraram equivalentes ao MRS na capacidade de recuperação das cepas padrão em cultura pura. O meio de cultura HHD apresentou melhor desempenho em relação a capacidade de recuperação das células, na avaliação com as cepas em diferentes misturas e, presentes em iogurtes e leite fermentado. Através do estudo da viabilidade das bactérias lácticas, presentes nos produtos analisados, verificou-se que os prazos de validade dos produtos se mostraram adequados, do ponto de vista da contagem total de bactérias viáveis. Em relação à contagem de L.acidophilus, somente 62% apresentaram contagem de células viáveis, dentro do valor mínimo requerido de 106 UFC/mL. E, em relação à contagem de bifidobactéria, apenas um produto apresentou contagem dentro do valor mínimo requerido.
Abstract: This is a study about the behaviour of the different strains of lactic acid bacteria (eg: Lactobacillus acidophilus, L. lactis, L. delbruekií susp. bulgaricus, Streptococus thermophilus) and bifidobacteria, with different culture media (MRS, MRS- maltose, MRS -salicin, HHD eLA), in order to evaluate the similarity among them, the capacity of each one to recover and the capacity to enumerate different strains. Firstly we checked the behaviour of the pure strains then the strains in different mixtures and finally the strains existing in the yogurt and fermented milk that are commercialized in Brazilian market. We also study the viability of the lactic acid bacteria in yogurt during refrigerated storage. The results demonstrated that the four culture media were similary to the MRS in the capacity of recovering when the pure strain was checked. The culture media HHD was the best in the capacity of recovering with strains in different mixtures and with the strains existing in the yogurt and fermented milk. Through the study of the viability of the lactic acid bacteria in the products, it showed that the validity was adequate, at least, in the total counting of viable bacteria. However, in the counting of L. acidophilus, only 62% maintained viability of 106 UFC/mL (minimum level]. In The counting of bifidobactéria, only one product maintained viable cells with minimum leveI.
Mestrado
Mestre em Tecnologia de Alimentos
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Allegretti, Luciana. "Isolamento e identificação de Lactobacillus spp., Bifidobacterium spp., Enterococcus spp., Pediococcus spp. e Lactococcus spp. da microbiota intestinal de Papagaio-verdadeiro (Amazona aestiva)". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/10/10133/tde-08122009-143059/.
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No Brasil, o papagaio-verdadeiro (Amazona aestiva) é uma das aves mais procuradas como animal de estimação e comercializadas ilegalmente. Na literatura pouco é descrito sobre a microbiota intestinal de aves silvestres. O trato intestinal das aves é composto por inúmeras e diferentes espécies bacterianas. A grande maioria são bactérias gram-positivas pertencentes ao grupo de bactérias ácido-láticas. Este estudo teve como objetivo isolar e identificar a presença de bactérias dos gêneros Lactobacillus, Bifidobacterium, Enterococcus, Pediococcus e Lactococcus na microbiota entérica de papagaios Amazona aestiva de vida livre e de cativeiro. Para isto foram coletadas amostras de 26 aves de vida livre e de 26 aves procedentes de dois criadouros comerciais. O Enterococcus foi o gênero que apresentou maior freqüência de isolamentos (100%), seguido dos gêneros Pediococcus (63,46%), Lactobacillus (28,84%), Lactococcus e Bifidobacterium (15,38%). Foram isoladas 12 espécies de Enterococcus, sendo o E. faecium a espécie que apresentou maior ocorrência de isolamento, presente em 63,46% das aves, seguido por E. faecalis isolado em 57,69% das aves, Enterococcus sp. identificado em 46,15% das aves, E. hirae em 30,76% e E. raffinosus em 19,23%. Seis espécies de Pediococcus foram isoladas, sendo que P. pentosaceus foi a mais freqüente e esteve presente em 57,69% das aves. Foram isoladas cinco (5) espécies de Lactococcus, sendo L. lactis subsp. cremoris isolados em 3,84% das aves e Lactococcus sp. em 9,61%. Lactobacillus apresentou uma maior diversidade, com 14 espécies identificadas, sendo as mais freqüentes L. coryniformis subsp. torquens e L. sanfrancisco com 7,69% de aves positivas para cada espécie. Três (3) espécies de Bifidobacterium foram isoladas, sendo B. bifidum identificado em 9,61% das aves. Estudos complementares precisam ser conduzidos para uma melhor compreensão da microbiota intestinal das aves silvestres, assim como analisar as similaridades e diferenças com as aves domésticas, o que permitirá um manejo apropriado e menos empírico desta espécie em cativeiro.In Brazil, Blue-fronted Parrot (Amazona aestiva) has been widely owned as a pet bird and, therefore, one of the Brazilians birds most frequently traded illegally in the Black Market. There are few reports in the current literature regarding to the microbiota of wild birds. The gastrointestinal tract of these birds has a wide variety of bacterial species; most of them are Gram positive bacteria and belongs to the lactic acid group. The present study has isolated and identified Lactobacillus, Bifidobacterium, Enterococcus, Pediococcus, and Lactococcus bacterias present in fecal samples of wild and captive Amazona aestiva parrots. Fifty two fecal samples were collected from 26 wild parrots and 26 parrots from commercial breeders. Enterococcus genus was the most frequently isolated (100%), followed by Pediococcus (63.46%), Lactobacillus (28.84%), Lactococcus and Bifidobacterium (15.38%). Twelve species of Enterococcus were identified. E. faecium was the most frequently isolated from the birds representing 63.46%, followed by E. faecalis (57.69%), Enterococcus sp. (46.15%), E. hirae (30.76%), and E. raffinosus (19.23%). P. pentosaceus was identified from 57.69% of the parrots. This specie was the most frequently isolated. Five different species of Lactococcus were found out. Lactococcus sp. was identified from 9.61% of the birds, while L. lactis subsp. lactis represented 3.84%. Fourteen different species of Lactobacillus were isolated, showing the biggest diversity among all the studied genera. L. coryniformis subsp. torquens and L. sanfrancisco were isolated from 7.69% of the birds. Three different species of Bifidobacterium were isolated, and B. bifidum was identified in 9.61% of the birds, being the most frequently isolated. Further studies are needed to a better comprehension of the microbiota in wild birds. Besides comparing differences and similarities between wildlife parrots and pet birds will allow appropriate and less empiric management of those birds in captivity.
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Freire, Carlise Beddin Fritzen. "Efeito da adição de Bifidobacterium Bb-12 e/ou do emprego da acidificação direta sobre as propriedades de queijo minas frescal". reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/92796.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Ciência dos Alimentos, Florianópolis, 2009Made available in DSpace on 2012-10-24T12:26:47Z (GMT). No. of bitstreams: 1 269443.pdf: 4704779 bytes, checksum: 3dc5bd16aab6623905caaa445cbe66cc (MD5)
Em uma primeira etapa foi avaliado o efeito da adição da bactéria probiótica Bifidobacterium Bb-12 e de ácido lático nas propriedades microbiológicas, físico-químicas, reológicas, microestruturais e de cor de queijo Minas Frescal nos dias 1 e 28 de armazenamento (5 ± 1 °C). Queijos sem ácido lático (Q1 e Q2) e com ácido lático (Q3 e Q4) foram fabricados, sendo a bifidobactéria adicionada nos queijos Q2 e Q3. Durante o armazenamento, queijos com bifidobactéria puderam ser classificados como probióticos, pois apresentaram contagem de células viáveis acima de 6 log UFC/g. A adição da bifidobactéria nos queijos Q2 e Q3 não influenciou (p > 0,05) no rendimento, no teor protéico e lipídico. Além disso, no dia 28, os queijos sem ácido lático apresentaram menor (p < 0,05) umidade em comparação aos adicionados de ácido lático, influenciando no comportamento reológico e microestrutural, tornando-os mais elásticos, firmes e compactos, no entanto, todos os queijos avaliados demonstraram comportamento viscoelástico com maior contribuição da componente viscosa. Os valores de L* e b* diminuíram (p < 0,05) durante o armazenamento em todos os queijos, sendo que apenas os adicionados de bifidobactéria mantiveram os valores de a* e ?E, ao longo dos 28 dias. Em uma segunda etapa foi realizada a avaliação sensorial dos queijos Minas Frescal contendo a bifidobactéria e diferenciados quanto à adição de ácido lático, através de testes de comparação pareada-preferência, perfil de consumidores, aceitabilidade global e intenção de compra. A adição de ácido lático não interferiu (p > 0,05) na preferência dos queijos, no entanto, os consumidores que avaliaram este produto apresentaram como perfil o gênero feminino, com idade entre 18 e 27 anos e que já possuem o hábito de consumir alimentos que ajudam a melhorar o funcionamento do intestino. Além disso, pôde-se observar que a maioria dos consumidores classificou os queijos como de boa aceitabilidade, sendo que comprariam este tipo de alimento funcional.
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Val, Cid Cristina. "STRUCTURAL-FUNCTIONAL ANALYSIS OF LACTO-N-BIOSIDASE FROM Bifidobacterium bifidum: A POTENTIAL BIOCATALYST FOR THE PRODUCTION OF HUMAN MILK OLIGOSACCHARIDES". Doctoral thesis, Universitat Ramon Llull, 2016. http://hdl.handle.net/10803/387327.
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Els efectes beneficiosos que els oligosacàrids de la llet materna (OLM) confereixen a la salut dels lactants s'ha estudiat durant anys. Aquests oligosacàrids proporcionen una barrera protectora i un suport nutritiu essencials, als quals no tenen accés els nens que no prenen llet materna. La llet humana és considerada única respecte a la resta de llets de mamífers pel que fa a la quantitat i la complexitat d'oligosacàrids. Actualment, s'han identificat més de 130 estructures químiques diferents de OLM, i no es disposa de cap recurs natural que proporcioni accés a aquestes estructures tan complexes i a bastament. De la mateixa manera, la síntesi química és complicada a causa de l'estructura tan complexa i diversa que presenten els OLM, i de moment, la síntesi en gran escala no ha estat possible. La síntesi enzimàtica, en canvi, es presenta com una eina alternativa de síntesi d'aquestes molècules complexes atès que, en la naturalesa els enzims són els responsables de formar enllaços glicosídics entre carbohidrats amb alta regio- i estereoselectivitat.
L'objectiu d'aquesta tesi és avaluar l'ús de l'enzim Lacto-N-biosidasa de Bifidobacterium bifidum (LnbB) com un biocatalizador eficient des de dues perspectives diferents: i) l'estudi estructural-funcional de LnbB i ii) la generació de biocatalizadors capaços de sintetitzar l'oligosacàrid d'interès (lacto-N-tetraosa) mitjançant enginyeria de proteïnes en l'enzim LnbB.
En aquesta tesi, hem analitzat l'organització dels dominis dels enzims de la família GH20, i, en conseqüència, hem definit dos models d'arquitectures. El Model A conté almenys dos dominis, un domini GH20b no catalític i el GH20 catalític, que sempre es presenta acompanyat d'una α-hèlix extra. En canvi, el Model B consisteix únicament en el domini catalític GH20. Mitjançant l'expressió de diferents formes truncades de LnbB, hem descrit els requeriments estructurals per a la funcionalitat dels enzims GH20, i en particular per LnbB, per tal d’obtenir la unitat funcional mínima que conservi l'activitat enzimàtica.
Respecte a la síntesi de la lacto-N-tetraosa usant com a biocatalizador noves proteïnes de LnbB obtingudes mitjançant enginyeria de proteïnes, hem contemplat dues estratègies enzimàtiques diferents. En primer lloc, l'estratègia de glicosintasa, en la qual l'enzim (amb mutació en el residu assistent) és capaç de transferir el corresponent donador activat (sucre sintètic derivat d’oxazolina) a un acceptor, sense hidròlisi del producte. En segon lloc, l'estratègia de transglicosilació millorada, en la qual, una nova generació de mutants en els llocs d'unió a l'acceptor seran capaços d'acomodar de manera més favorable un sucre en lloc d'una molècula d'aigua, i d'aquesta manera, augmentar l'activitat de transglicosilació.Los efectos beneficiosos que los oligosacáridos de la leche materna (OLM) confieren a la salud de los lactantes se han estudiado durante años. Estos oligosacáridos proporcionan una barrera protectora y un soporte nutritivo esenciales, a los que, los niños que no toman leche materna no tienen acceso. La leche humana se considerada única respecto al resto de leches de mamíferos en cuanto a cantidad y complejidad de oligosacáridos. Actualmente, se han identificado más de 130 estructuras químicas diferentes de OLM, y no se dispone de ningún recurso natural que proporcione acceso a estas estructuras tan complejas y en cantidad suficiente. Del mismo modo, la síntesis química es complicada debido a la estructura tan compleja y diversa que presentan los OLM, y por el momento, la síntesis en gran escala no ha sido posible. La síntesis enzimática, en cambio, se presenta como una herramienta alternativa de síntesis de éstas moléculas complejas dado que, en la naturaleza las enzimas son las responsables de formar enlaces glicosídicos entre carbohidratos con alta regio- y estereoselectividad. El objetivo de esta tesis es evaluar el uso del enzima Lacto-N-biosidase de Bifidobacterium bifidum (LnbB) como un biocatalizador eficiente desde dos perspectivas diferentes: i) el estudio estructural-funcional de LnbB y ii) la generación de biocatalizadores capaces de sintetizar el oligosacárido de interés (lacto-N-tetraosa) mediante ingeniería de proteínas en el enzima LnbB. En esta tesis, hemos analizado la organización de los dominios de enzimas GH20, y, en consecuencia, hemos definido dos modelos de arquitecturas de dominio. El Modelo A contiene al menos dos dominios, un dominio GH20b no catalítico y el GH20 catalítico, que siempre se presenta acompañado de una α-hélice extra. Por el contrario, el Modelo B consiste únicamente en el dominio catalítico GH20. Mediante la expresión de diferentes formas truncadas de LnbB, hemos descrito los requerimientos estructurales para la funcionalidad de las enzimas GH20, y en particular para LnbB, de modo que se obtenga la unidad funcional mínima que conserve la actividad enzimática. Respecto a la síntesis de la lacto-N-tetraosa usando como biocatalizador nuevas proteínas de LnbB obtenidas mediante ingeniería, hemos contemplado dos estrategias enzimáticas diferentes. En primer lugar, la estrategia de glicosintasa, en la que el enzima (un mutante en el residuo asistente) es capaz de transferir el correspondiente dador activado (azúcar sintético derivado de oxazolina) a un aceptor, sin hidrólisis del producto. En segundo lugar, la estrategia de transglicosilación mejorada, en la que, una nueva generación de mutantes en los sitios de unión al aceptor serán capaces de acomodar de manera más favorable un aceptor de azúcar en lugar de una molécula de agua, y de este modo, aumentar la actividad de transglicosilación.
The potential health benefits of human milk oligosaccharides (HMO) have been studied for many years. It is well known that these oligosaccharides provide a protective barrier and nutritive support that infants with poor access to breast milk do not acquire in the first years of life. Human milk is considered to be unique among mammals in terms of the quantity and complexity of its oligosaccharides. To date, 130 chemical structures within HMO have been identified. No other natural resources provide access to these complex oligosaccharides in such large amounts, and until now, large scale synthesis of HMO has not been possible by any traditional organic chemistry methodology. Enzymatic synthesis is an alternative synthetic tool since enzymes can form the new glycosidic linkage between carbohydrates with high regio- and stereoselectivity. The objective of this thesis is to evaluate the use of Lacto-N-biosidase from Bifidobacterium bifidum (LnbB) as an efficient biocatalyst in the following two ways: i) the structural-functional study of LnbB and ii) protein engineering of LnbB to generate biocatalysts able to synthesize the target lacto-N-tetraose. Here, we have analysed the domain organization of GH20 enzymes, and accordingly, have defined two models of domain architectures. Model A, contains at least two domains, a non-catalytic GH20b domain, and the catalytic GH20 which is always accompanied with an extra α-helix. In contrast, Model B consists only of the catalytic GH20 domain. By expressing different truncated forms of LnbB, we have described the structural requirements for functionality of GH20 enzymes, and in particular for LnbB, to obtain a minimal functional unit that retains the enzymatic activity. With regard to the synthesis of lacto-N-tetraose using new engineered LnbB proteins as biocatalysts, we envisage two different enzymatic strategies. First, the glycosynthase strategy, in which the activated donor is the corresponding synthetic sugar oxazoline and the enzyme, a mutant on the assisting residue, is able to transfer the donor to an acceptor without hydrolysis of the product. Second, the enhanced transglycosidase strategy, in which, a new generation of mutants on the acceptor subsites of the enzyme will be able to more favourably accommodate a sugar acceptor instead of water, and thus, increase transglycosylation activity.
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Fritsch, Caroline Monika Tanja [Verfasser], Rudi F. [Akademischer Betreuer] [Gutachter] Vogel i Wilfried [Gutachter] Schwab. "Interaction of lupin and sunflower secondary plant metabolites with lactic acid- and bifidobacteria / Caroline Monika Tanja Fritsch. Betreuer: Rudi F. Vogel. Gutachter: Wilfried Schwab ; Rudi F. Vogel". München : Universitätsbibliothek der TU München, 2016. http://d-nb.info/1104368072/34.
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Rodrigues, Florence Ana Carolina. "Réponses physiologiques de bifidobactéries soumises aux stress acide, froid et gastro-intestinal en laits biologique et conventionnel". Phd thesis, AgroParisTech, 2013. http://pastel.archives-ouvertes.fr/pastel-01053733.
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Les bifidobactéries sont exposées à de nombreux stress, liés aux conditions environnementales rencontrées lors de la production, du stockage au froid, et pendant la digestion des laits fermentés. Afin d'améliorer leur survie, cette étude vise la compréhension des mécanismes de dégradation de l'état physiologique de différentes souches de Bifidobacterium soumises aux stress froid et acide et au stress gastro-intestinal simulé in vitro. Elle ambitionne également d'établir des relations entre la résistance aux différents stress et la teneur en acides gras membranaires et des laits biologiques et conventionnels. Les résultats montrent que l'activité acidifiante des bifidobactéries est souche-dépendante et qu'elle augmente lorsque les bactéries sont associées aux bactéries lactiques du yaourt, avec du lait biologique et lorsque la température d'incubation est fixée à 42°C au lieu de 37°C. La cultivabilité et la survie des souches ont été déterminées après fermentation, après stockage à 4°C pendant 7 à 28 jours, et pendant un processus de digestion simulé in-vitro dans un digesteur dynamique reproduisant le tractus gastro-intestinal. Ces caractéristiques sont améliorées dans les laits fermentés biologiques par rapport aux produits conventionnels, lorsque la fermentation est effectuée à 42°C jusqu'à pH 4,4, et lorsque les laits fermentés sont maintenus à 28°C pendant 12 heures avant d'être refroidi à 4°C. Ces procédures de fabrication spécifiques génèrent ainsi une adaptation physiologique des bifidobactéries aux stress. Pendant la digestion in-vitro, la cultivabilité des bifidobactéries se dégrade moins lorsque la fermentation se déroule en lait biologique plutôt qu'en lait conventionnel et, dans une moindre mesure, lorsque les procédures d'adaptation sont appliquées pendant la fabrication du lait fermenté. Ces résultats sont liés aux teneurs plus élevées en acides gras insaturés, en particulier en acides trans-vaccénique, linoléique conjugué et α-linolénique, qui caractérisent les produits biologiques. Ces profils d'acides gras particuliers aux laits biologiques permettent aux bifidobactéries de modifier leur composition en acides gras membranaires, en augmentant leur teneur en acides gras insaturés et en raccourcissant la longueur moyenne des chaînes d'acides gras saturés, adaptant ainsi leur fluidité membranaire. Lorsque les procédures de fabrication spécifiques sont mises en oeuvre pour induire une adaptation physiologique des bifidobactéries, la composition en acides gras des membranes se modifie différemment de ce qui est observé en lait biologique. Cette différence indique ainsi que d'autres mécanismes biologiques d'adaptation sont probablement impliqués, en particulier au niveau protéomique. Finalement, cette étude démontre que les modifications au niveau de la membrane contribuent à moduler la résistance aux stress technologique et gastro-intestinal de souches de Bifidobacterium.
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Riegelová, Kristýna. "Molekulární identifikace vybraných druhů bakterií mléčného kvašení a bifidobakterií v doplňcích stravy". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216692.
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Probiotic lactic acid bacteria and bifidobacteria are natural part of microflora of gastrointestinal tract. In the present, day they are grossly exploited in food processing industry. The aim of the work was molecular identification of bacteria of genus Lactobacillus and Bifidobacterium in complex matrices of two food additives. Total DNA was isolated from crude cell lysates by magnetic particles P(HEMA-co-GMA). Isolated DNA was amplified in genus-specific and species-specific PCRs. Amplicons were detected by agarose gel electrophoresis. Results were compared with declared specification given by producers in three different batches.
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Sedláková, Lucie. "Analýza DNA izolované z různých typů probiotických výrobků s využitím PCR v reálném čase a HRM analýzy". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-240562.
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The aim of this diploma thesis was to introduce real-time PCR with high-resolution melting analysis for Bifidobacterium species. Currently a small number of publication, dealing with identification of Bifidobacterium species using high-resolution melting analysis, is available. According to publications dealing with identification of lactic acid bacteria were selected primers P1V1 and P2V1, LAC1 and LAC2, LsppUPF and LsppUPR, V3F and V3R, V6F and V6R. Using this primers bacterial DNA was amplified by real-time PCR with high-resolution melting analysis. After evaluation of the measured results efficiency of selected primers was verified on DNA izolated from complex sample of probiotic product. After further optimisation real-time PCR with high-resolution melting analysis could be suitable using selected primers for Bifidobacterium species.
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Balogová, Petra. "Izolace a identifikace DNA probiotických bakterií v komplexních matricích". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-216583.
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Nowadays, probiotic lactic acid bacteria (LAB) and bifidobacteria are plentifully exploited in food processing industry. LAB and bifidobacteria are important part of microflora of gastro intestinal tract (GIT). Probiotics (most often just lactobacilli and bifidobakteria) can be supplied to the GIT of the organism like food complements. Species identification is therefore very important. New methods of identification of LAB and bifidobacteria are based on analysis of DNA. Mostly exploited method is polymerase chain reaction (PCR). In my diploma work, genus and species specific PCRs were used for identification of different species of bacteria of genus Lactobacillus and Bifidobacterium in complex matrices of six food supplements (Zenflo, Linex Forte, Probian, Nutra Bona, GS lactobacillus Forte, Pangamin Bifi plus). Total DNA was isolated from crude lysates of cells present in tablets by magnetic particles coated by carboxyl groups . The preparation of cell lysates was optimalised. Different amounts of lysozyme (3 mg/ml, 10 mg/ml), time of incubation at laboratory temperature (1,5 hour, 3 hour) and time of incubation with SDS and proteinase K at 55 °C (1 hour, 3 hour, over all night) were tested. Isolated DNA was quantified and checked in PCR. Primers specific for genus Lactobacillus and Bifidobacterium and for species Lb. acidophilus, Lb. casei, Lb. rhamnosus and Lb. plantarum and B. animalis, B. bifidum, B. infantis, B. longum were used, respectively. All identified bacteria were in accord with the data declared by producer in 3 food supplements (Zenflo, Linex Forte and Pangamin Bifi Plus). The genus indentification was in accord with declaration of producer in other food products only (Probian, Nutra Bona, GS Laktobacily Forte).
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Pepper, Susan Jessie. "Characterisation of stress responses in Lactobacillus paracasei and Bifidobacterium animalis (syn. lactis)". Thesis, 2004. https://vuir.vu.edu.au/15664/.
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This thesis describes a study of the nature of the responses to stress, particularly acid stress, in
Lactobacillus paracasei and Bifidobacterium anitnalis (syn. lactis). The aims of the study were validate the identification of the bacteria being studied, to determine the nature of their stress responses and compare them to known responses and to gain information regarding the proteins up-regulated during stress.
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Ho, Jamie, i 何祖琪. "Effects of Fucoidan and Fucoxanthin on Bifidobacterium lactis growth and Caco-2 cell proliferation". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/txkm49.
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碩士中國文化大學
生物科技研究所
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The immune system is the critical barrier which prevents infection from microbial pathogens, which is directly associated with the development of diseases. Accumulated studies have indicated that probiotic bacterias are capable of inducing cytokines to be released from our intestinal cells and play crucial roles in the regulation of physiological functions, such as immune boosting. To date, an increasing number of studies have demonstrated that fucoidan ,as well as fucoxanthin, are involved in the improvement of collagen and epidermis formation, amelioration of hyperglycemia, and various anticancer effects. For the regulation of immune system, however, whether fucoidan/fucoxanthin supplements are involved in the regulation of intestinal cell proliferation and residential probiotic bacteria is still not understood. Furthermore, if/how fucoidan/fucoxanthin supplements affect the incremental value of probiotic bacterial-induced immune boosting as well as reduction of allergic reactions via intestinal cells is still obscured. The goals of this study are to determine 1) whether fucoidan/fucoxanthin have an effect on Bifidobacterium lactis Bb-12 growth, 2) fucoidan/fucoxanthin effects on Caco-2 cell growth, 3) fucoidan/fucoxanthin effect on levels of IL-8 and IL-10 in Caco-2 cells.
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Darukaradhya, Jyothsna, University of Western Sydney, of Science Technology and Environment College i of Science Food and Horticulture School. "Enumeration and survival studies of free and encapsulated Lactobacillus Acidophilus and Bifidobacterium Lactis in Cheddar cheese". 2005. http://handle.uws.edu.au:8081/1959.7/24126.
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The regulatory standards set by food authorities globally for probiotic foods such as Cheddar cheese makes it essential to have reliable enumeration media that will accurately monitor the survival of probiotic bacteria over the shelf life of Cheddar cheese. This study therefore investigated various selective and differential media for reliable enumeration of Lactobacillus acidophilus, Bifidobacterium spp., starter lactic acid bacteria (SLAB) and non-starter lactic acid bacteria (NSALB) from Cheddar cheese using pure cultures and commercial probiotic Cheddar cheese. All media showed variation in counts and selectivity. Some reported selective media failed to inhibit SLAB and NSLAB. The media that were reliable and also gave good recovery were, Reinforced Clostridium Agar with Bromocresol green and Clindamycin (RCABC), which was selective for L. acidophilus spp. and Reinforced Clostridium Agar with Aniline blue and Dicloxacillin (RCAAD), which was differential for Bifidobacterium spp. and SLAB. Reinforced Clostridium Agar with Bromocresol green and Vancomycin (RCABV) was found suitable for NSLAB. Additionally, an enzyme based colorimetric assay was modified successfully and used as a confirmatory test to check the presence of bifidobacterial colonies on enumeration media. Six batches of probiotic Cheddar cheese were manufactured with the incorporation of LAFTI L10 (L. acidophilus) and LAFTI B94 (B. lactis). The survival of probiotic bacteria, SLAB and NSLAB were monitored over a six-month ripening period using the selected media. The survival of free probiotic bacteria throughout the ripening process decreased consistently in all the six batches. In order to enhance the survival of probiotic bacteria, the effect of microencapsulation on the viability of LAFTI L10 and LAFTI B94 in Cheddar cheese was studied. Six batches of Cheddar cheese were manufactured with the incorporation of alginate-starch encapsulated and free cells of LAFTI L10 and LAFTI B94. The survival of both the encapsulated and free probiotic bacteria was studied over a six month ripening period. The survival of encapsulated LAFTI L10 and LAFTI B94 (107 cfu/g) was found to be significantly better than that of free bacteria (105 cfu/g) at the end of six months of ripening period in Cheddar cheese.Master of Applied Science (M. App. Sci.) (Biotechnology)
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Mamvura, Chiedza Isabel. "Poly-(vinylpyrrolidone)-poly-(vinylacetate-co-crotonic acid) (PVP : PVAc-CA) interpolymer complex microparticles encapsulating a Bifidobacterium lactis Bb12 probiotic strain: microparticle characterization and effect on viability of encapsulated probiotic cells". Diss., 2012. http://hdl.handle.net/2263/29325.
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Microorganisms have been known to play a major role in human health since early times. The ingestion of microorganisms as probiotics to restore and/or maintain health is a widely accepted and common practice. The challenge in industry is to ensure viability of probiotics until their ingestion to their site of action, the colon, for health benefits to be realised. Microencapsulation is one of the techniques used to protect probiotic bacteria and ensure viability. A method that does not involve the use of extreme temperatures and/or solvents which would otherwise adversely affect viable cells was developed and patented. The method is solventless and is based on complexation of Food and Drug Administration-approved polymers, poly (vinylpyrrolidone) and poly (vinylacetate-co-crotonic acid) in supercritical carbon dioxide. The use of this method of encapsulation was found to be suitable in target release in earlier studies. Microparticles produced were found to have pH-dependent swellability, protecting bioactives, in this case probiotic bifidobacteria, in acid (simulated gastric acid) and only releasing them in an alkaline environment (simulated intestinal fluid). Further studies were, however, needed to investigate the suitability of the microparticles for food and pharmaceutical applications. The current study therefore aimed to characterize these microparticles in terms of size range, distribution of bacteria within the microparticles, and particle size distribution. The average size of the Bifidobacterium lactis Bb12-encapsulating microparticles was found to be within the acceptable size in food applications. High encapsulation efficiency was obtained, with live bacteria distributed evenly within the microparticles, demonstrating the potential of the microparticles to deliver high numbers of probiotic cultures as required for this type of microorganisms to deliver purpoted benefits to the consumer. Probiotic products are normally kept under refrigerated storage, yet the viability of bacterial cells still decreases. An additional benefit of encapsulation within microparticles would be protection of the encapsulated probiotics from the detrimental factors to which the probiotic products are exposed during storage. In order to investigate this for the microparticles in this study, the shelf life of encapsulated B. lactis Bb 12 powder stored in glass vials was investigated. High temperatures were used for accelerated shelf life studies. Encapsulated B. lactis Bb 12 maintained the viable levels above the therapeutic minimum for the duration of the study (12 weeks), which was 7 weeks more than was the case with unencapsulated probiotic. Thus the microparticles provided protection to the probiotic cultures at temperatures much higher than those normally used for storage of probiotic products. These results further indicate the possibility for storage of the B. lactis Bb12 encapsulated in the tested microparticles, at ambient temperatures for at least two months, without drastic loss of culture viability. Research has recently focused on the development of probiotic foods other than dairy and dairy-based foods. This has been necessitated by increasing vegetarian lifestyle and concerns of allergenicity. A maize-based traditional fermented beverage, mageu, was investigated for use as a vehicle for probiotic delivery. Although no significant difference was noted between survival of encapsulated and unencapsulated probiotic was noted, pH decrease in mageu with encapsulated B. lactis Bb 12 was less than with unencapsulated cells. This suggested that encapsulation would ensure that metabolites produced by encapsulated probiotics, if any, would not negatively affect a product in which they are incorporated. Further studies may be needed for investigation of the effect of the encapsulating microparticles in traditional fermented non-dairy products, using more acid-sensitive probiotic strains as the test strain used in the current study is well-known for its inherent resistance to acidity. This study filled gaps in knowledge in terms of the characteristics of microparticles produced using supercritical technology. The main highlights of the research findings were that the microparticles were suitable for food applications, improved probiotic viability under nonrefrigerated temperatures, and delayed browning of the probiotic powder and minimized drop in pH of the fermented product containing the probiotic encapsulated within. The results showed that microparticles encapsulating B. lactis Bb 12 are appropriate to consumers in areas where refrigeration is absent. Furthermore, the study showed that mageu is a suitable alternative vehicle to dairy-based products, for delivery of probiotic B. lactis Bb 12. This possibility extends accessibility of probiotic products to consumers who do not take dairy products for various reasons. There is also a potential increase of probiotic products on the market. CopyrightDissertation (MSc)--University of Pretoria, 2012.
Microbiology and Plant Pathology
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Darukaradhya, Jyothsna. "Enumeration and survival studies of free and encapsulated Lactobacillus Acidophilus and Bifidobacterium Lactis in Cheddar cheese". Thesis, 2005. http://handle.uws.edu.au:8081/1959.7/24126.
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The regulatory standards set by food authorities globally for probiotic foods such as Cheddar cheese makes it essential to have reliable enumeration media that will accurately monitor the survival of probiotic bacteria over the shelf life of Cheddar cheese. This study therefore investigated various selective and differential media for reliable enumeration of Lactobacillus acidophilus, Bifidobacterium spp., starter lactic acid bacteria (SLAB) and non-starter lactic acid bacteria (NSALB) from Cheddar cheese using pure cultures and commercial probiotic Cheddar cheese. All media showed variation in counts and selectivity. Some reported selective media failed to inhibit SLAB and NSLAB. The media that were reliable and also gave good recovery were, Reinforced Clostridium Agar with Bromocresol green and Clindamycin (RCABC), which was selective for L. acidophilus spp. and Reinforced Clostridium Agar with Aniline blue and Dicloxacillin (RCAAD), which was differential for Bifidobacterium spp. and SLAB. Reinforced Clostridium Agar with Bromocresol green and Vancomycin (RCABV) was found suitable for NSLAB. Additionally, an enzyme based colorimetric assay was modified successfully and used as a confirmatory test to check the presence of bifidobacterial colonies on enumeration media. Six batches of probiotic Cheddar cheese were manufactured with the incorporation of LAFTI L10 (L. acidophilus) and LAFTI B94 (B. lactis). The survival of probiotic bacteria, SLAB and NSLAB were monitored over a six-month ripening period using the selected media. The survival of free probiotic bacteria throughout the ripening process decreased consistently in all the six batches. In order to enhance the survival of probiotic bacteria, the effect of microencapsulation on the viability of LAFTI L10 and LAFTI B94 in Cheddar cheese was studied. Six batches of Cheddar cheese were manufactured with the incorporation of alginate-starch encapsulated and free cells of LAFTI L10 and LAFTI B94. The survival of both the encapsulated and free probiotic bacteria was studied over a six month ripening period. The survival of encapsulated LAFTI L10 and LAFTI B94 (107 cfu/g) was found to be significantly better than that of free bacteria (105 cfu/g) at the end of six months of ripening period in Cheddar cheese.
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Briczinski, Elizabeth Panko. "Characterization of strains of Bifidobacterium animalis ssp. lactis from commercial starter culture manufacturers - a study of glucose transport". 2007. http://etda.libraries.psu.edu/theses/approved/WorldWideIndex/ETD-2352/index.html.
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Labuschagne, Markus Christof. "Vegetal BM 297 ATO as a potential food grade coating material for microencapsulation of Bifidobacterium lactis Bb12 probiotic strain under supercritical conditions". Diss., 2014. http://hdl.handle.net/2263/43139.
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The use of probiotics administered either in a direct clinical sense or indirectly as a food additive
has grown greatly in recent years due to the new 'healthy living' trend. The global market for
probiotics was worth R186.2 billion in 2013, showing a growth of 4.3% compounded per annum
over a period of five years. Probiotics are however sensitive to different environmental factors
such as light, moisture and oxidation in addition to the stresses encountered during processing.
The shelf of probiotics in foodstuffs and pharmaceuticals are limited, which lead to increased
costs to the manufacturer in having to incorporate enough cultures to account for losses, or a
decreased benefit to the consumer in not receiving the required amount of cells needed for health
benefits to be actualized. Microencapsulation is a technique used to protect probiotic cells
against harsh conditions encountered both in the environment during storage and transport, and
in the human body after consumption. This leads to higher numbers of viable probiotic cells
being available to the consumer after consumption and decreased costs to the manufacturer as
less cells need to be added.
Current microencapsulation techniques are plagued with problems such as the inability to be
produced at an industrial scale, the use of toxic solvents which kill the probiotic cells and
contribute to pollution and the need for FDA approval of the pharmaceutical grade excipients
they use. A novel encapsulation technique using the Particles from a Gas Saturated Solution (PGSS)
system has been developed by the Council for Scientific and Industrial Research (CSIR), which
does not require organic solvents and uses carbon dioxide in a supercritical state to create
microcapsules.
There is very limited knowledge on the use of lipid based food grade excipients for use in
probiotic microencapsulation for food applications. The combination of these ideas could result
in a novel method of protecting sensitive food additives, in addition to creating a platform for
new techniques in the pharmaceutical and food industries.
Bifidobacteria were successfully encapsulated using the novel PGSS method. Two lipid based
excipients, Compritol E 472 ATO and Vegetal BM 297 ATO were tested to determine if they
could be used in the microencapsulation of bifidobacteria. Results showed that the temperature
needed to successfully liquefy the Compritol resulted in high losses of cells. It was decided to
continue the study with only Vegetal BM 297 ATO which resulted in much lower losses of
probiotic cells. The results demonstrated that the cells were successfully encapsulated inside
Vegetal BM 297 ATO microparticles. The particles contained high numbers of cells and the
process did not cause any morphological changes on the probiotic cells. The process was
optimized by changing the reaction formulation and mixing chamber parameters until an
encapsulation efficiency (EE) of 88% was attained. The Vegetal microparticles containing the
bifidobacteria were a very desirable size for use in the food industry. This was the first time the
use of a lipid based food grade excipient in microencapsulation of probiotics using a PGSS
procedure was demonstrated. This result leads to further testing of the Vegetal BM 297 ATO
microparticles containing bifidobacteria in in vitro gastrointestinal environments.
It was found that the Vegetal BM 297 ATO matrix provided a protective effect on the cells
during simulated gastrointestinal transit. There were more viable cultures in the sample
containing encapsulated cells after exposure to simulated gastric fluid (SGF) and subsequently
simulated intestinal fluid (SIF). The cells were released from the Vegetal BM 297 ATO matrix
over 7 hours after an initial decrease in numbers. The viable numbers of non-encapsulated cells
continuously decreased while the encapsulated cells continuously increased over time during
exposure. The microparticles were subsequently tested to see if they increased the shelf life of
bifidobacteria under different storage conditions. It was found that during refrigerated storage the
microparticles did not increase the shelf life of bifidobacteria, but that it had a slight protective
effect when stored at room temperature.Dissertation (MSc)--University of Pretoria, 2014.
lk2014
Microbiology and Plant Pathology
MSc
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Moussavi, Mahta. "Comparative analysis of the viability and functional performance of mono- and multi-species probiotic cultures in a non-dairy food matrix". Thesis, 2012. http://hdl.handle.net/1959.13/934262.
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Research Doctorate - Doctor of Philosophy (PhD)Probiotics are increasingly being included into food products in order to develop functional foods with health promoting effects, but have to date been exploited mainly in dairy products. Development of non-dairy probiotic foods such as fruit juices may provide consumers with greater choice and be attractive to those who can not eat dairy foods. Orange juice presents as an ideal vehicle for probiotic delivery as it is the most popular fruit beverage worldwide, and like other fruit juices has a short gastro-intestinal transit time which reduces exposure of probiotics to harsh environment of the stomach. Since probiotic organisms vary in the type and level of their health promoting effects, it is likely that probiotic combinations would offer the consumer more benefit than single strains. Effective design of functional foods containing probiotic combinations, must take into consideration the likely occurrence and impact of potential interactions between individual species within a proposed combination, and between the probiotic and the carrier matrix. The main objectives of the current study were 1) to identify the effect of combining probiotics on their viability and adhesion to intestinal cells and 2) to examine the combined effect of exposure of probiotics to orange juice and low temperatures during refrigerated storage, on their viability and functional properties. The initial study of long-term (14 days) growth interactions of several lactobacilli and Bifidobacterium animalis subsp lactis Bb12 (Bb), both alone and in co-culture with Propionibacterium jensenii 702 (PJ), revealed that growth patterns of Lactobacillus strains were not adversely affected by the presence of PJ, whereas lactobacilli strongly inhibited growth of PJ. In the co-culture of Bb and PJ, a significant enhancement of the growth of both bacteria was observed. The effect of combining probiotics on their adhesion to human intestinal epithelial Caco-2 cells was only evident in the case of Lb. casei 01 and Lb. rhamnosus GG (LG) which exhibited a decrease in adhesion rate in the presence of PJ. The viability of LG, Lb. reuteri ATCC 55730 (LR), Bb and PJ, both individually and as 2- or 3- multispecies combinations, were then monitored in orange juice (OJ) (with and without 20% pulp) as well as bottled drinking water (BW) over 8 weeks of refrigerated (4ºC) and non-refrigerated storage (only for BW). Lactobacilli remained viable in higher numbers in OJ relative to that observed in BW under refrigeration. In contrast, a better outcome was observed for Bb and PJ in BW. Combining of probiotic species was observed to affect individual strain viability. Presence of pulp did not affect the viability of probiotics in OJ, while storage of BW at room temperature had an adverse effect on viability of all probiotics except of PJ, relative to storage under refrigeration. Influence of combined exposure to OJ and refrigerated storage of the same probiotic preparations on their in vitro gasto-intestinal tolerance, adhesion to intestinal epithelial cells and immunomodulatory effects was then investigated at 10-day intervals during one month of storage. Suspension in OJ did not adversely affect the tolerance of any of the strains examined to simulated gastric juice (SGJ), with the tolerance of LG and PJ considerably enhanced relative to that observed in PBS, but did appear to impair the tolerance of lactobacilli and PJ to simulated intestinal juice (SIJ) at the baseline. High tolerance to SGJ was maintained throughout the storage period. The tolerance of both Bb and PJ to SIJ remained relatively constant during storage. Combining with both Bb and PJ enhanced the tolerance of the lactobacilli to SIJ with little impact on Bb, but adversely affected PJ in all combinations. The adhesion rate of LG remained relatively constant in all preparations along with the viability during storage. In contrast with LG, adhesion rates and viabilities of other probiotics exhibited variation in relation to strain, presence of other microorganisms, and storage duration. In terms of both viability and adhesion rate, the preparations that provided the best outcomes for all constituents were LG and LR-PJ. With the exception of LG, all probiotic preparations significantly enhanced non-stimulated interleukin-8 (IL-8) but not interleukin-6 (IL-6) or tumor necrosis factor-α (TNF-α) secretion by Caco-2 cells. Probiotic preparations enhanced Escherichia coli lipopolysaccharide (LPS) induced IL-8 release at baseline however this effect was not evident in all preparations at day 10. With the exception of LG, all probiotic preparations enhanced TNF-α induced IL-8 secretion towards day 20 after which it returned to the control level. In contrast, probiotic preparations significantly reduced IL-1β induced IL-8 secretion at baseline, with no further effect evident during storage. The relative probiotic effect on IL-1β and TNF-α induced IL-8 secretion showed an upward and downward trend respectively over the storage period. Probiotic preparations did not affect LPS or IL-1β induced secretion of IL-6 up to 10 days of storage, while thereafter some of them exhibited variable effects on IL-1β induced IL-6 secretion. Compared to baseline (day 0), the effect of all four probiotic strains on IL-1β induced TNF-α production was found to decrease significantly by day10 of the storage period. In conclusion, the results provided evidence of variation between individual strains in terms of their viability and intestinal adhesion capacity, and for the same strain when combined with different probiotics. When included in bottled drinking water and orange juice, the viabilities and functional properties of the probiotic preparations were further affected by the duration of their exposure to the carrier matrix and refrigerated storage. Such effects should be considered when formulating probiotic products, and further research is recommended to confirm the observed in vitro functional effects in vivo.