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Potentiel probiotique des bactéries lactiques de l'écosystème mammaire bovin contre les mammites à Staphylococcus aureus / Probiotic potential of lactic acid bacteria from bovine mammary ecosystem against Staphylococcus aureus mastitisBouchard, Damien 14 November 2013 (has links)
Staphylococcus aureus est un des pathogènes majeurs impliqué dans les mammites chez les ruminants. Il engendre des tableaux cliniques très variable, allant des mammites subcliniques aux mammites gangréneuses, mais les mécanismes de cette variabilité restent encore mal connu. La volonté de réduire l'utilisation d'antibiotiques en médecine vétérinaire ainsi que leurs faibles efficacités contre les mammites staphylococciques soulignent la nécessité de développer de nouvelles stratégies alternatives. L'une des particularités des infections intramammaires à S. aureus est leur pouvoir chronique et persistent dont l'une des principales causes est la capacité de S. aureus à adhérer et internaliser dans les tissus de l'Hote. L'un des concepts ayant fait ses preuves chez l'Homme et l'animal se base sur le concept de la lutte biologique en utilisant les propriétés inhibitrices des bactéries dites « probiotique » d'un écosystème pour réduire, prévenir ou traiter les infections. Cette étude vise à mieux caractériser le microbiote mammaire et notamment la composante lactique qui par analogie avec les autres écosystèmes jouent un rôle positif sur la santé de l'Hôte et de déterminer son potentiel à moduler l'adhésion et l'internalisation de S. aureus. L'ensemble de ce travail a été réalisé avec deux souches de S. aureus très différentes au niveau des tableaux cliniques engendrés. La souche RF122, très virulente et la souche Newbould 305, induisant des infections chroniques. Deux messages clairs ressortent des analyses indépendantes du pathogène et du microbiote : d'une part, l'édute comparative in silico et in vitro révèle que l'invasion cellulaire semble être majeur pour la chronicité de la souche Newbould 305 et d'autre part que l'écosystème de la glande mammaire présente une composante lactique ayant des capacités probiotiques intéressantes. Dans notr! e modèle d'interaction tripartite, trois acteurs ont été retenus, S. aureus, Lactobacillus casei et les cellules épithéliales mammaires MAC-T. Dans ce système, L. casei affecte l'adhésion et surtout l'internalisation de S. aureus sans modifier la viabilité et la morphologie des cellules en culture. Les mécanismes identifiés dans l'inhibition semblent dépendant d'un contact direct avec des L. casei viables et permettent de poursuivre la caractérisation des bases moléculaires de ce phénomènes impliquant une modulation des gènes de virulence et cellulaire lors d'interaction avec une flore compétitrice. Ces résultats ouvrent de nouvelles perspectives dans l'application de bactéries lactiques en tant que probiotique mammaire. / Staphylococcus aureus is one of the main pathogen involved in ruminant mastitis. Severity of bovine S. aureus mastitis is highly variable, from subclinical to gangrenous mastitis. Nevertheless S. aureus factors that may explain this variability still poorly documented. The need to reduce antibiotics in veterinary medicine as well as their low efficiencies against staphylococcal mastitis underline the necessity to develop new alternative strategies. One of the particularity of S. aureus infections is his ability to persist within the mammary tissue and induce chronicity of the infection. One of the main causes is the ability of S. aureus to adhere to and internalize into host cells. The concept of biological control, using natural inhibitory properties of lactic acid bacteria as probiotics, are now well etablished in human and animal ecosystem for their ability to reduce, prevent or treat bacterial infections. This study aims to better characterize the mammary microbiota in p! articular the lactic component which by analogy with the other ecosystems play a positive role in the host health and to determine his potential to modulate adhesion and internalization of S. aureus. This work was realized with two S. aureus strains with different severity degree. The virulent strain RF122 and the Newbould 305 one, involved in chronic mastitis. Two main messages came out from the independent analyses of the pathogen and the microbiota: on one hand, the in silico and in vitro comparison of the two strains reveals that the cellular invasion propress seems to be major for the chronicity of the Newbould 305 strain and on the other hand that the bovin mammary ecosystem presents a lactic biodiversity with interesting probiotic capacities. In our model of tripartite interaction, three actors were retained, S. aureus, Lactobacillus casei and the mammary epithelial cells MAC-T. In this system, L. casei affect the adhesion and internalization of S. aureus without mod! ifying the viability and the morphology of cells in culture. Mechanisms identified in the inhibition seem dependent on a direct contact with live L. casei and allow to continue the molecular basis of the virulence and cells genetic expression modulation during interaction with a competitive flora. These results open new perspectives in the application of lactic acid bacteria as mammary probiotic.
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Production d'acide lactique par Lactobacillus casei subsp. rhamnosus sur jus de datte : cinétique et optimisation en cultures discontinues, semi-continues et continues / Production of lactic acid by Lactobacillus casei subsp. rhamnosus on date juice : kinetic and optimisation during batch, fed-batch and continuous culturesNancib, Ayacha 24 October 2007 (has links)
L’objectif de ce travail a été de développer un procédé performant de production d’acide lactique par Lactobacillus casei subsp. rhamnosus sur jus de datte. Dans une première partie, des cultures en mode discontinu ont été réalisées afin d’étudier les besoins nutritionnels de la souche. Ces études ont pour but de décrire les effets des sources carbonées, azotées et les vitamines sur la production d’acide lactique. Nous avons montré que le sulfate d’ammonium est une bonne alternative économique et nous avons pu déterminer la faisabilité de minimiser l’ajout de l’extrait de levure par l’utilisation partielle de l’extrait de levure combinée avec du sulfate d’ammonium plus l’ajout de vitamines du groupe B. Des cultures pures et mixtes de Lactobacillus casei et Lactococcus lactis ont été réalisées. Le système de culture mixte donne de meilleurs résultats concernant la production d’acide lactique et l’utilisation des sucres comparés à ceux obtenus en cultures pures de Lactobacillus casei ou Lactococcus lactis. L’effet des sucres purs (glucose et fructose) et mixtes (glucose/fructose) sur la production d’acide lactique a été étudié. La production d’acide lactique est plus importante avec un mélange de sucres qu’avec des sucres non mélangés ce qui explique les performances de fermentation sur jus de datte. Dans une seconde partie, une stratégie d’alimentation du réacteur en culture semi-continue a été mise en œuvre, permettant d’améliorer les performances de la fermentation. Les deux facteurs influençant le bon fonctionnement sont le débit et la concentration du milieu d’alimentation. Dans une troisième partie, une étude cinétique a été développée en réacteurs continus. Nous avons étudié l’influence du taux de dilution sur la croissance, l’utilisation du substrat et la production d’acide lactique. La productivité du procédé continu a été considérablement augmentée en comparaison avec le procédé discontinu. Enfin, dans une dernière partie, un modèle a été établi. Ce modèle, bien qu’imparfait, permet apparemment de simuler la croissance, la consommation des sucres de jus de datte et la production d’acide lactique en culture discontinue / The aim of this work was to develop an efficient process of lactic acid production by Lactobacillus casei subsp. rhamnosus on date juice In a first part, the batch cultures were realized to carry out the nutritional requirement of the strain. These studies allowed us to describe the effects of carbon substrates, nitrogen substrates and vitamins on the lactic acid production. We showed that ammonium sulphate is a satisfying economic alternative and we have determined feasibility of minimizing the addition of the yeast extract by the partial use of yeast extract combined with the ammonium sulphate plus the addition of vitamins of the group B. Pure and mixed cultures of Lactobacillus casei and Lactococcus lactis were carried out. The mixed system gives better results concerning the lactic acid production and the use of the sugars compared with those obtained in pure cultures of Lactobacillus casei or Lactococcus lactis. The effect of pure sugars (glucose and fructose) and mixed sugars (glucose/fructose) on the lactic acid production was studied. The lactic acid production is more important on mixed sugars than on pure sugars what explains the performances of fermentation on date juice. In a second part, a mode of fed batch operations was defined to improve the performances of the fermentation. The two factors influencing the process are the feeding rate and the concentration of the feeding medium. In a third part, kinetic study in continuous culture was developed. We studied the influence of dilution rate on growth, substrate utilization and lactic acid production. The productivity of the continuous process was considerably increased in comparison with the batch process. Finally, a tentative model has been established for the fermentation process. The corresponding model, although not perfect, is apparently able to simulate growth rate, substrates uptake and lactic acid production in batch culture
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Concentração inibitória mínima e concentração bactericida mínima de extratos hidroalcoólicos das folhas de Myracrodruon urundeuva All. e Qualea grandiflora Mart. sobre Streptococcus mutans e Lactobacillus casei / Minimum inhibitory concentration and minimum bactericidal concentration of hydroalcoholic extracts of Myracrodruon urundeuva All. and Qualea grandiflora Mart. leaves on Streptococcus mutans and Lactobacillus caseiFabris, Rita de Cassia 11 August 2017 (has links)
A cárie dentária é uma doença bucal de alta prevalência e impactante em países em desenvolvimento. É causada pela presença de biofilme dentário rico em bactérias acidogênicas e acidúricas, como Streptococcus mutans e Lactobacillus casei. Neste sentido, a fitoterapia tem sido aplicada na odontologia devido ao seu conhecido efeito antimicrobiano, tendo potencial para prevenir doenças como a cárie dentária. Portanto, o presente estudo tem como objetivo testar o potencial antimicrobiano de extratos bruto e etanólico das folhas de Myracrodruon urundeuva (M. urundeuva.) e Qualea grandiflora (Q. grandiflora) sobre S.mutans e L. casei. Para tal, determinaram-se a Concentração Inibitória Mínima (CIM) e a Concentração Bactericida Mínima (CBM). A CIM foi definida como a menor concentração do agente antimicrobiano capaz de inibir 100% o crescimento microbiano (absorbância) em relação aos controles negativos. Para a CBM, alíquotas foram removidas dos poços que não apresentaram nenhuma absorbância (viabilidade, concentrações CIM) e semeadas em placas de ágar BHI, incubadas por 24 h a 37°C em estufa de CO2 5%. A CBM foi determinada considerando a menor concentração dos extratos capaz de impedir o crescimento bacteriano visível. Cepas de S. mutans (ATCC 21175) e L. casei (ATTC 334) foram ativadas em BHI e caldo Rogosa, respectivamente. A CIM foi determinada pela técnica de diluição em microplacas de 96 poços (100 l de extrato + 80 l BHI/Rogosa + 20 l da bactéria diluída em BHI/Rogosa equivalente a 5x105 UFC/mL), as quais foram incubadas por 24 h (S. mutans) e 48 h (L. casei) a 37°C em estufa de CO2 5%. Os extratos de M. urundeuva e Q. grandiflora inicialmente foram diluídos em BHI/Rogosa variando as concentrações entre 2 mg/ml a 0,00012207 mg/ml e os mesmos extratos diluídos em álcool foram avaliados nas concentrações entre 20 mg/ml a 0,00244 mg/ml para S. mutans e L. casei. Não foi possível determinar a CIM e a CBM para os extratos diluídos no BHI/Rogosa. Foram utilizados como controle positivo a clorexidina e como controles negativos BHI/Rogosa com e sem álcool a 5%. As CIMs (CBMs) da M. urundeuva e Q. grandiflora, diluídas em álcool, e clorexidina contra S. mutans foram 2,5 mg/ml (2,5 mg/ml), 5,0 mg/ml (--) e 0,00468 mg/ml (0,00937 mg/ml), respectivamente. Em relação ao L. casei, as CIMs (CBMs) da M. urundeuva e Q. grandiflora, diluídas em álcool, e da clorexidina foram 0,156 mg/ml (0,312 mg/ml), 0,156 0,625 mg/ml (0,312 0,625mg/ml) e 0,00468 mg/ml (0,3 mg/ml), respectivamente. Como conclusão, nosso estudo mostrou que L. casei (ATTC 334) é mais susceptível aos extratos que S. mutans (ATCC 21175) e o extrato M. urundeuva apresenta melhor efeito antimicrobiano que a Q. grandiflora em S. mutans (ATCC 21175), porém os dois extratos apresentam efeito similar sobre L. casei (ATTC 334) e ambos foram inferiores à CHX. / Dental caries is an oral disease of high prevalence and impact in developing countries. It is caused by the presence of a dental biofilm rich in acidogenic and aciduric bacteria, such as Streptococcus mutans and Lactobacillus casei. Accordingly, phytotherapy has been applied in dentistry due to its known antimicrobial effect, having potential to prevent diseases such as dental caries. Therefore, the present study aims to test the antimicrobial potential of crude and ethanolic extracts of Myracrodruon urundeuva (M. urundeuva) and Qualea grandiflora (Q. grandiflora) leaves on S. mutans and L. casei. For this, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were determined. MIC was defined as the lowest concentration of the antimicrobial agent capable of inhibiting 100% the microbial growth in comparison to the negative controls. For MBC, aliquots were removed from the wells that did not show any absorbance (viability, concentrations than MIC) and seeded on BHI agar plates, incubated for 24 h at 37°C and 5% CO2. The MBC was determined considering the lowest concentration of extracts capable of preventing visible bacterial growth. Strains of S. mutans (ATCC 21175) and L. casei (ATTC 334) were activated in BHI and Rogosa broth. MIC was determined by the dilution technique in 96-wells microplates (100 l of extract + 80 l BHI/ Rogosa + 20 l of bacterium diluted in BHI/Rogosa equivalent to 5x105 CFU/ml), which were incubated for 24 h (S. mutans) and 48 h (L. casei) at 37°C and 5% CO2. The extracts were firstly diluted in BHI/Rogosa varying the concentrations between 2 mg/mL and 0.00012207 mg/ml; the same extracts were also diluted in alcohol at concentrations ranging from 20 mg/ml to 0.00244 mg/ml and both tested against S. mutans and L. casei. It was not possible to determine the MIC and MBC for the extracts diluted in BHI/Rogosa. Chlorhexidine was used as positive control, while BHI/Rogosa with or without 5% alcohol were used as negative controls. The MICs (MBCs) of M. urundeuva and Q. grandiflora diluted in alcohol, and clorexidine against S. mutans were 2.5 mg/ml (2.5 mg/ml), 5.0 mg/ml (--) and 0.00468 mg/ml (0.00937 mg/ml), respectively. In respect to L. casei, the MICs (MBCs) of M. urundeuva and Q. grandiflora, diluted in alcohol, and chlorhexidine were 0.156 mg/ml (0.312 mg/ml), 0.156 0.625 mg/ml (0.312 0.625 mg/ml) and 0.00468 mg/ml (0.3 mg/ml), respectively. In conclusion, our study showed that L. casei (ATTC 334) is more susceptible than S. mutans (ATCC 21175) to the extracts and the extract of M. urundeuva has a better antimicrobial effect than Q. grandiflora against S. mutans (ATCC 21175), but both extracts have similar effect on L. casei (ATTC 334) and they were inferior to CHX.
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Production and spray drying of probiotic beverage made from the fermentation of cashew apple juice / ElaboraÃÃo e secagem em spray dryer de bebida probiÃtica formulada a partir da fermentaÃÃo do suco de cajuAna Lucia Fernandes Pereira 07 February 2013 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / The objective of this study was to develop a probiotic cashew apple juice ready to drink and in the dehydrated form through spray drying. The first stage of the study was the optimization of Lactobacillus casei NRRL B-442 cultivation in cashew apple juice, to optimize the proper inoculum amount and the fermentation time. The optimum conditions for probiotic cashew apple juice production were: initial pH 6.4, fermentation temperature of 30ÂC, inoculation level of 7.48 log CFU/mL (L. casei) and 16 h of fermentation process. Cashew apple juice showed to be as efficient as dairy products for L. casei growth. In a second stage, the stability of probiotic cashew apple juice stored for 42 days at 4ÂC was evaluated. Analyses were conducted in the non fermented cashew apple juice (control), and in the fermented juices with L. casei NRRL B-442, with 8% (w/v) of sucrose (sugar table), after fermentation, and without the addition of sugar. The viability of the probiotic bacteria, sugars and organic acids content, color, antioxidant and enzymatic activity, and sensory characteristics were evaluated during the storage. Viable cell counts increased in the probiotic cashew apple containing sucrose along the storage period. Moreover, the fermentation lead to the preservation of the ascorbic acid content, which had a less intense reduction in the fermented cashew apple juices compared to the non fermented sample. The antioxidant activity and total polyphenolic compounds of cashew apple juice had a similar trend. Browning reactions and nutritional breakdown caused by enzymes were minimized in the fermented samples during storage. In these samples, a higher reduction of the enzymatic activity of polyphenoloxidase and peroxidase activity was observed. During the storage, the increase in the chroma values indicated that yellowness was reinforced, being well accepted by consumers. The sensory attributes (aroma, flavor, acidity and color) of probiotic cashew apple juice were positively influenced by storage under refrigeration for 42 days. In the third stage of the research, the effects of dehydration by spray drying in cashew apple juice containing L. casei NRRL B-442 was assessed and the influence of storage temperature on the viability of L. casei NRRL B-442 and physical properties of the powder were evaluated during 35 days of storage. The drying agents used were: 20% (w/v) maltodextrin or 10% (w/v) maltodextrin + 10% (w/v) arabic gum. The powder of probiotic cashew apple juice showed satisfactory levels of L. casei survival, during drying. During storage, the addition of 10% (w/v) maltodextrin + 10% (w/v) arabic gum kept microbial viability within satisfactory levels when the powder was subjected to cooling at 4ÂC. However, greater differences in the reconstituted powder color and higher rehydration time were obtained in this condition. On the other hand, the addition of 20% (w/v) maltodextrin provided better yield. In conclusion, cashew apple juice is a good substrate for the probiotic beverage production, and the condition of drying agents 10% maltodextrin + 10% arabic gum is adequate to maintain satisfactory levels of L. casei NRRL B-442 survival for 35 days, in the powder of probiotic cashew juice stored at 4ÂC. / O objetivo desta pesquisa foi elaborar um produto probiÃtico à base de suco de caju pronto para beber, como tambÃm, na forma desidratada obtida pela secagem por aspersÃo (spray drying). A primeira etapa da pesquisa consistiu em otimizar as condiÃÃes de crescimento do Lactobacillus casei NRRL B-442 em suco de caju, a quantidade adequada de inÃculo e o tempo de fermentaÃÃo. As condiÃÃes Ãtimas para produÃÃo do suco de caju probiÃtico foram: pH inicial de 6,4, temperatura de fermentaÃÃo de 30ÂC, quantidade de inÃculo de 7,48 log UFC/mL (L. casei) e 16 h de fermentaÃÃo. O suco de caju mostrou ser tÃo eficiente quanto os produtos lÃcteos para o crescimento de L. casei. Em uma segunda etapa, foi avaliada a estabilidade da bebida probiÃtica de caju estocada por 42 dias a 4ÂC. Foram realizadas anÃlises no suco de caju nÃo fermentado (controle) e nos sucos fermentados com L. casei NRRL B-442, adicionado ou nÃo de 8% (p/v) de sacarose depois da fermentaÃÃo. Durante a estocagem, foram realizadas as determinaÃÃes de viabilidade de L. casei NRRL B-442, conteÃdo de aÃÃcares e Ãcidos orgÃnicos, cor, atividade antioxidante e enzimÃtica e aceitaÃÃo sensorial. Foi observado que o nÃmero de cÃlulas viÃveis aumentou no suco de caju contendo sacarose ao longo da estocagem. AlÃm disso, a fermentaÃÃo proporcionou um efeito conservante no conteÃdo de Ãcido ascÃrbico que teve uma reduÃÃo menos intensa, com a estocagem, nos sucos fermentados, quando comparados com o controle. A atividade antioxidante e o conteÃdo de polifenÃis apresentaram similar tendÃncia. ReaÃÃes que reduzem o valor nutricional causadas por enzimas foram minimizadas nas amostras fermentadas durante a estocagem. Nessas amostras foi observada maior reduÃÃo da atividade enzimÃtica da polifenoloxidase e peroxidase. Durante a estocagem, o aumento do croma indicou que a cor amarela foi intensificada, sendo bem aceita pelos consumidores. Os atributos sensoriais (aroma, sabor, acidez e cor) do suco de caju probiÃtico foram positivamente influenciados pela estocagem sob refrigeraÃÃo por 42 dias. Na terceira etapa da pesquisa, foi avaliado o efeito da desidrataÃÃo por spray drying no suco de caju contendo L. casei NRRL B-442, alÃm de avaliar a influÃncia da temperatura de estocagem sobre a viabilidade de L. casei e nas propriedades fÃsicas do pÃ, durante 35 dias de estocagem. Os agentes de secagem usados foram: 20% (p/v) de maltodextrina ou 10% (p/v) de maltodextrina + 10% (p/v) de goma arÃbica. O suco de caju probiÃtico desidratado por spray drying apresentou nÃveis satisfatÃrios de sobrevivÃncia de L. casei NRRL B-442, durante a secagem. Durante a estocagem, a adiÃÃo de 10% (p/v) de maltodextrina + 10% (p/v) de goma arÃbica manteve a viabilidade microbiana dentro de nÃveis satisfatÃrios quando o pà foi submetido à refrigeraÃÃo a 4ÂC. Entretanto, maiores diferenÃas na coloraÃÃo do pà reconstituÃdo e maior tempo de reidrataÃÃo foram obtidos nesta condiÃÃo. Jà a adiÃÃo de 20% (p/v) de maltodextrina proporcionou melhor rendimento. Em conclusÃo, o suco de caju pode ser utilizado como substrato para o desenvolvimento de bebida probiÃtica, e a condiÃÃo dos agentes de secagem de 10% de maltodextrina + 10% de goma arÃbica mostra-se adequada para manter os nÃveis satisfatÃrios de L. casei NRRL B-442 por atà 35 dias, no suco de caju probiÃtico desidratado estocado a 4ÂC.
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Desenvolvimento de uma nova bebida funcional probiótica à base de melão Cantaloupe sonificado / Development of a new probiotic functional drink based of ultrasonicated Cantaloupe juiceFonteles, Thatyane Vidal January 2011 (has links)
FONTELES, Thatyane Vidal. Desenvolvimento de uma nova bebida funcional probiótica à base de melão Cantaloupe sonificado. 2011. 122 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Departamento de Tecnologia de Alimentos, Programa de Pós-Graduação em Ciências e Tecnologia de Alimentos, Fortaleza-CE, 2011 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-28T14:35:13Z
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Previous issue date: 2011 / The use of fruit juices for the development of functional foods has been an alternative for people who do not want or cannot make use of fermented dairy products. The objective of this research was the development of a drink with probiotic properties trough the fermentation of melon juice by Lactobacillus casei NRRL B-442. The first stage of the work consisted of the optimization of pH and temperature of fermentation for the L. casei cultivation in melon juice. Results showed that this strain has fermentative potential in melon juice, with no need of nutrient supplementation to reach the appropriated values of pH and viable cells. The best operating condition found to guarantee a good growth of the microorganism and ensure the cellular viability necessary for the product to be considered probiotic was the temperature of 31°C with initial pH of 6.1. The technological advantage of using melon juice as a substrate for probiotic fermentation was demonstrated in this work because the natural pH of the juice provided a favorable environment for the probiotic microorganism development. In a second stage, the effect of ultrasound treatment on quality parameters of melon juice was investigated as a function of intensity of ultrasonic energy and treatment time. The ultrasonic processing intensity using 372.93 W/cm2 for 10 minutes improved the quality of the juice reducing the spoilage due to enzyme activity, increasing homogeneity without damaging the product color. In the third phase of the research, the kinetics of probiotic melon juice fermentation and the influence of the product storage under refrigeration on the beverage quality parameters such as survival of L. casei, post-acidification and color were studied. The melon juice was subjected to ultrasonic processing (372.93 W/cm2/10min) and inoculated with 1% (v/v) and incubated at 31°C for 8 hours. The fermented juice was stored at 4°C, and pH, color, cell biomass, and viable cells number were evaluated. Analyses were performed at intervals of 7 days until 42 days of storage. The highest cell count was achieved within 12 hours of study, reaching 9.0 log CFU/mL, but from the 8th of fermentation there was no significant increase in the concentration of viable cells. Thus, 8 hours was elected as the optimal fermentation time to prepare the probiotic melon juice. During refrigerated storage there was acid production and a slight reduction in the number of viable cell. However, the product kept the number of viable cells above the level recommended by the current legislation during 42 days of storage at 4°C, regardless of having been stocked sugar-free or with sugar addition and no damage to the product color was observed. Melon juice was considered a good vehicle for probiotic microorganism as it showed viable cell count higher than 8 log CFU/mL throughout the studied period. / A utilização de sucos de frutas para o desenvolvimento de alimentos funcionais probióticos tem sido uma alternativa de consumo para indivíduos que não querem ou não podem fazer uso de produtos lácteos fermentados. Desse modo, o objetivo deste trabalho foi desenvolver uma bebida com propriedades probióticas à partir da fermentação do suco de melão Cantaloupe por Lactobacillus casei NRRL B-442. A primeira etapa da pesquisa consistiu na otimização de parâmetros de pH e temperatura de fermentação para o desenvolvimento de L. casei no suco de melão. Os resultados mostraram que a linhagem probiótica estudada apresentou potencial fermentativo em suco de melão, não havendo necessidade de suplementação com nutrientes para a obtenção de valores adequados de pH e número de células viáveis. A melhor condição encontrada que garantisse um bom crescimento do micro-organismo além de assegurar a viabilidade celular necessária para que o produto seja considerado probiótico foi a temperatura de 31°C com o pH inicial do suco de 6,1. Neste trabalho foi demonstrada a vantagem tecnológica do uso de suco de melão como substrato para a fermentação probiótica uma vez que o pH natural do suco proporcionou um meio favorável para o desenvolvimento do micro-organismo. Em uma segunda etapa, investigou-se o efeito do tratamento ultra-sônico nos parâmetros de qualidade do suco de melão em função da intensidade de energia ultra-sônica e do tempo de tratamento. O processamento ultra-sônico utilizando intensidade de 372,93 W/cm2 durante 10 minutos melhorou as características de qualidade do suco reduzindo a atividade de enzimas deteriorantes, aumentando a homogeneidade sem causar danos à cor do produto. Considerando estes resultados, na terceira etapa da pesquisa foram estudadas a cinética da produção de suco de melão sonificado probiótico e a influência da estocagem sob refrigeração em parâmetros de qualidade da bebida como: sobrevivência de L. casei, pós-acidificação e cor. O suco de melão foi submetido ao processamento ultra-sônico, inoculado com 1% (v/v) da cultura e incubado a 31ºC por 8 horas. Os sucos foram armazenados sob refrigeração a 4°C. Foram determinados pH e parâmetros de cor da bebida, crescimento celular e o número de células viáveis. As análises foram realizadas em intervalos de 7 dias, até o 42º dia de estocagem. A maior contagem celular foi atingida nas 12 horas do estudo, chegando a 9,0 log UFC/mL, porém a partir de 8ª hora não houve um aumento significativo da concentração de células viáveis, motivo pelo qual elegeu-se 8 horas como o tempo de fermentação ideal para a elaboração do suco de melão probiótico. Durante a estocagem refrigerada, houve produção de ácidos e uma discreta redução do número de células viáveis, porém o produto manteve prevalência de células viáveis (com índices acima do preconizado pela legislação vigente), durante 42 dias de armazenamento a 4°C, independentemente de terem sido estocadas com ou sem açúcar sem prejuízos à coloração do produto. O suco de melão foi considerado um veículo adequado para a ingestão de micro-organismos probióticos, pois apresentou contagem de células viáveis superior a 8 log UFC/mL durante todo o período de estudo.
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Identification des gènes impliqués lors de l'établissement de Lactobacillus casei dans l'intestin et caractérisation de l'opéron LSEI_0219-0221 / Identification of the genes involved in the establishment of Lactobacillus casei in the gut and characterization of the LSEI_0219_0221Scornec, Hélène 04 November 2014 (has links)
Chez les bactéries en contact direct avec leur milieu, la transcription des gènes et la synthèse des protéines sont régulées de manière efficace à chaque changement des paramètres environnementaux afin de permettre la survie cellulaire. Dans le cas des bactéries commensales de l’intestin, ces régulations doivent aussi permettre les interactions symbiotiques et la colonisation dont les mécanismes moléculaires, encore peu connus, sont probablement liés, entre autres, à la surface des bactéries (molécules exposées et sécrétées…). Lactobacillus casei, bactérie commensale, possède environ 330 gènes prédits comme intervenant dans la composition et la fonctionnalité de la surface cellulaire. Afin d’avoir une vue globale de la totalité des gènes qui interviennent dans l’établissement de L. casei dans l’intestin, une approche de génétique inverse a été réalisée. Pour cela, une banque de mutants aléatoires étiquetés de L. casei par « Signature-Tagged Mutagenesis » a été créée puis annotée et réorganisée grâce au séquençage des régions d’insertion du transposon. Les mutants ont été criblés quant à leur capacité à s’établir dans l’anse iléale ligaturée de lapin et quantifiés par qPCR. Parmi les 47 gènes identifiés comme étant impliqués dans l’établissement in vivo, trois gènes en opéron codant pour un système à deux composants et une « penicillin-binding protein » ont été caractérisés. Ces trois gènes sont impliqués dans la modulation de la surface cellulaire et plus particulièrement dans la régulation des hydrolases du peptidoglycane qui sont nécessaires à la protection de la bactérie dans l’environnement intestinal. / In bacteria which are in direct contact with their environment, genes transcription and proteins synthesis are efficiently regulated at each change of environmental parameters to allow cell survival. For intestinal commensal bacteria, these regulations must also allow symbiotic interactions and colonization whose molecular mechanisms, so far little known, are probably related, among others, to the bacteria surface (molecules exposed and secreted…). Lactobacillus casei, a commensal bacterium, has about 330 predicted genes involved in the composition and functionality of the cell surface. To have a global view of the whole genes involved in the establishment of L. casei in the gut, a reverse genetics approach was performed. For that, a library of L. casei random labeled-mutants by Signature-Tagged Mutagenesis was generated then annotated and reassembled thanks to the sequencing of transposon insertion sites. Mutants were screened for their ability to establish themselves in the rabbit ligated ileal loop and quantified by qPCR. Among the 47 genes identified as involved in the in vivo establishment, three genes in an operon encoding a two-component system and a penicillin-binding protein were characterized. These three genes are involved in the cell surface modulation and particularly in the regulation of peptidoglycan hydrolases which are required for the bacteria protection in the intestinal environment.
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Concentração inibitória mínima e concentração bactericida mínima de extratos hidroalcoólicos das folhas de Myracrodruon urundeuva All. e Qualea grandiflora Mart. sobre Streptococcus mutans e Lactobacillus casei / Minimum inhibitory concentration and minimum bactericidal concentration of hydroalcoholic extracts of Myracrodruon urundeuva All. and Qualea grandiflora Mart. leaves on Streptococcus mutans and Lactobacillus caseiRita de Cassia Fabris 11 August 2017 (has links)
A cárie dentária é uma doença bucal de alta prevalência e impactante em países em desenvolvimento. É causada pela presença de biofilme dentário rico em bactérias acidogênicas e acidúricas, como Streptococcus mutans e Lactobacillus casei. Neste sentido, a fitoterapia tem sido aplicada na odontologia devido ao seu conhecido efeito antimicrobiano, tendo potencial para prevenir doenças como a cárie dentária. Portanto, o presente estudo tem como objetivo testar o potencial antimicrobiano de extratos bruto e etanólico das folhas de Myracrodruon urundeuva (M. urundeuva.) e Qualea grandiflora (Q. grandiflora) sobre S.mutans e L. casei. Para tal, determinaram-se a Concentração Inibitória Mínima (CIM) e a Concentração Bactericida Mínima (CBM). A CIM foi definida como a menor concentração do agente antimicrobiano capaz de inibir 100% o crescimento microbiano (absorbância) em relação aos controles negativos. Para a CBM, alíquotas foram removidas dos poços que não apresentaram nenhuma absorbância (viabilidade, concentrações CIM) e semeadas em placas de ágar BHI, incubadas por 24 h a 37°C em estufa de CO2 5%. A CBM foi determinada considerando a menor concentração dos extratos capaz de impedir o crescimento bacteriano visível. Cepas de S. mutans (ATCC 21175) e L. casei (ATTC 334) foram ativadas em BHI e caldo Rogosa, respectivamente. A CIM foi determinada pela técnica de diluição em microplacas de 96 poços (100 l de extrato + 80 l BHI/Rogosa + 20 l da bactéria diluída em BHI/Rogosa equivalente a 5x105 UFC/mL), as quais foram incubadas por 24 h (S. mutans) e 48 h (L. casei) a 37°C em estufa de CO2 5%. Os extratos de M. urundeuva e Q. grandiflora inicialmente foram diluídos em BHI/Rogosa variando as concentrações entre 2 mg/ml a 0,00012207 mg/ml e os mesmos extratos diluídos em álcool foram avaliados nas concentrações entre 20 mg/ml a 0,00244 mg/ml para S. mutans e L. casei. Não foi possível determinar a CIM e a CBM para os extratos diluídos no BHI/Rogosa. Foram utilizados como controle positivo a clorexidina e como controles negativos BHI/Rogosa com e sem álcool a 5%. As CIMs (CBMs) da M. urundeuva e Q. grandiflora, diluídas em álcool, e clorexidina contra S. mutans foram 2,5 mg/ml (2,5 mg/ml), 5,0 mg/ml (--) e 0,00468 mg/ml (0,00937 mg/ml), respectivamente. Em relação ao L. casei, as CIMs (CBMs) da M. urundeuva e Q. grandiflora, diluídas em álcool, e da clorexidina foram 0,156 mg/ml (0,312 mg/ml), 0,156 0,625 mg/ml (0,312 0,625mg/ml) e 0,00468 mg/ml (0,3 mg/ml), respectivamente. Como conclusão, nosso estudo mostrou que L. casei (ATTC 334) é mais susceptível aos extratos que S. mutans (ATCC 21175) e o extrato M. urundeuva apresenta melhor efeito antimicrobiano que a Q. grandiflora em S. mutans (ATCC 21175), porém os dois extratos apresentam efeito similar sobre L. casei (ATTC 334) e ambos foram inferiores à CHX. / Dental caries is an oral disease of high prevalence and impact in developing countries. It is caused by the presence of a dental biofilm rich in acidogenic and aciduric bacteria, such as Streptococcus mutans and Lactobacillus casei. Accordingly, phytotherapy has been applied in dentistry due to its known antimicrobial effect, having potential to prevent diseases such as dental caries. Therefore, the present study aims to test the antimicrobial potential of crude and ethanolic extracts of Myracrodruon urundeuva (M. urundeuva) and Qualea grandiflora (Q. grandiflora) leaves on S. mutans and L. casei. For this, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were determined. MIC was defined as the lowest concentration of the antimicrobial agent capable of inhibiting 100% the microbial growth in comparison to the negative controls. For MBC, aliquots were removed from the wells that did not show any absorbance (viability, concentrations than MIC) and seeded on BHI agar plates, incubated for 24 h at 37°C and 5% CO2. The MBC was determined considering the lowest concentration of extracts capable of preventing visible bacterial growth. Strains of S. mutans (ATCC 21175) and L. casei (ATTC 334) were activated in BHI and Rogosa broth. MIC was determined by the dilution technique in 96-wells microplates (100 l of extract + 80 l BHI/ Rogosa + 20 l of bacterium diluted in BHI/Rogosa equivalent to 5x105 CFU/ml), which were incubated for 24 h (S. mutans) and 48 h (L. casei) at 37°C and 5% CO2. The extracts were firstly diluted in BHI/Rogosa varying the concentrations between 2 mg/mL and 0.00012207 mg/ml; the same extracts were also diluted in alcohol at concentrations ranging from 20 mg/ml to 0.00244 mg/ml and both tested against S. mutans and L. casei. It was not possible to determine the MIC and MBC for the extracts diluted in BHI/Rogosa. Chlorhexidine was used as positive control, while BHI/Rogosa with or without 5% alcohol were used as negative controls. The MICs (MBCs) of M. urundeuva and Q. grandiflora diluted in alcohol, and clorexidine against S. mutans were 2.5 mg/ml (2.5 mg/ml), 5.0 mg/ml (--) and 0.00468 mg/ml (0.00937 mg/ml), respectively. In respect to L. casei, the MICs (MBCs) of M. urundeuva and Q. grandiflora, diluted in alcohol, and chlorhexidine were 0.156 mg/ml (0.312 mg/ml), 0.156 0.625 mg/ml (0.312 0.625 mg/ml) and 0.00468 mg/ml (0.3 mg/ml), respectively. In conclusion, our study showed that L. casei (ATTC 334) is more susceptible than S. mutans (ATCC 21175) to the extracts and the extract of M. urundeuva has a better antimicrobial effect than Q. grandiflora against S. mutans (ATCC 21175), but both extracts have similar effect on L. casei (ATTC 334) and they were inferior to CHX.
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OtimizaÃÃo da produÃÃo de Ãcido lÃtico por Lactobacillus casei NRRL B-442 em suco de caju clarificado / Optimization of lactic acid production by Lactobacillus casei NRRL B-442 in cashew clarified juiceAlexandre de AraÃjo Guilherme 21 August 2009 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O Ãcido lÃtico à um composto com diversas aplicaÃÃes industriais, dos quais as indÃstrias quÃmica, farmacÃutica, de alimentos, de polÃmeros, tÃxtil e de curtume podem ser citadas alÃm de ser reconhecido como seguro pela Food and Drug Administration (FDA). Tem se tornado um importante monÃmero na indÃstria de plÃsticos, sendo polimerizado em plÃstico biodegradÃvel. Pode ser obtido industrialmente atravÃs de sÃntese quÃmica ou processo fermentativo. No entanto, à mais comumente produzido via processo fermentativo atravÃs de matÃrias-primas renovÃveis e resÃduos da agroindÃstria. O pedÃnculo do caju possui um alto valor nutricional em termos de vitaminas, sais minerais e aÃÃcares e estima-se que 88% de sua produÃÃo seja perdida devido sua alta perecibilidade sendo, portanto, um substrato em potencial para processos fermentativos. O objetivo deste trabalho foi a otimizaÃÃo da produÃÃo de Ãcido lÃtico via fermentaÃÃo submersa em meio contendo suco de caju clarificado como substrato utilizando o Lactobacillus casei NRRL B-442. A partir de dados experimentais sobre temperatura, pH, concentraÃÃes de substrato e sulfato de amÃnia inicial, foi realizado um estudo cinÃtico variando concentraÃÃes de substrato inicial de 20 a 60 g/L e mantendo a proporÃÃo ideal de 12% de sulfato de amÃnio em relaÃÃo aos aÃÃcares redutores totais iniciais. Os ensaios foram realizados em reator batelada CSTR de 1,0 L com 0,5 L de meio reacional. A temperatura foi de 37ÂC e o pH foi ajustado para 6,5 sendo controlado durante o processo. A partir dos dados experimentais, um modelo fenomenolÃgico foi desenvolvido e um programa computacional foi criado utilizando Linguagem Fortran 90. O modelo foi validado estatisticamente segundo o valor de F de Fisher. Com o modelo representativo do sistema, foi possÃvel realizar otimizaÃÃes em batelada e batelada alimentada para a fermentaÃÃo lÃtica. Os processos em batelada e batelada alimentada foram comparados entre si levando em consideraÃÃo a eficiÃncia final, a produÃÃo de Ãcido lÃtico e os custos com matÃria-prima e reagentes utilizados comparando com os custos de venda final do Ãcido lÃtico no mercado. Para a otimizaÃÃo em batelada, pÃde-se verificar que a fermentaÃÃo que apresentou melhores resultados foi a que partiu de um inÃculo com 0,3 g/L e concentraÃÃo de aÃÃcares redutores totais iniciais de 50 g/L finalizando o processo com 39,31 g/L de Ãcido lÃtico e apresentando uma eficiÃncia de 72,2%. Em relaÃÃo ao processo em batelada alimentada, conclui-se que a simulaÃÃo que apresentou melhores resultados foi a que partiu de um inÃculo de 0,3 g/L com 40 g/L de aÃÃcares redutores totais iniciais, uma vazÃo de 3 L/h e uma concentraÃÃo de suco de caju clarificado concentrado alimentado de 200 g/L obtendo 38,0 g/L de Ãcido lÃtico e uma eficiÃncia de 63,8%. Portanto, para a fermentaÃÃo lÃtica utilizando o Lactobacillus casei NRRL B-442 tendo o suco e caju clarificado como substrato, o processo em batelada foi o mais vantajoso / Lactic acid is a compound that has several industrial applications in the chemical, pharmaceutical, food, polymer, textile and tanning industries. In addition, lactic acid has being recognized as safe by the Food and Drug Administration (FDA). Lactic acid has become an important monomer in the plastic industry where it has been polymerized into biodegradable plastics. It can be obtained industrially by chemical synthesis or fermentation process. It is most commonly produced by fermentation process using raw materials and waste materials of agricultural source. Cashew apple has a high nutritional value in terms of vitamins, minerals and sugars and it is estimated that 88% of its production is lost due the high spoilage, thus it has great potential as substrate in fermentative processes. This work aimed to optimize lactic acid production by submerged fermentation in a medium containing clarified cashew apple juice as substrate using the Lactobacillus casei NRRL B-442. From available information in the literature regarding temperature, pH, initial concentrations of substrate and initial ammonium sulfate, a kinetic study was carried out changing the initial concentration of substrate from 20 to 60 g/L and maintaining the ideal ratio of 12% of ammonium sulfate in relation of the initial total reducing sugars. The experiments were carried out in a batch reactor of 1.0 L with 0.5 L of reaction medium. The temperature was set at 37 ÂC and the pH was adjusted to 6.5 and controlled during the process. From the experimental data, a phenomenological model was developed and a computer program was built in Fortran 90. The mathematical model was statistically validated according to the F value of the Fisher test. With the representative model of the reaction system, it was possible to accomplish optimizations in batch and fed-batch fermentation for lactic acid production. The results in batch and fed-batch were compared, in relation to the final efficiency of the system, lactic acid production and costs of raw materials and reagents, with the costs of the final price of the lactic acid in the market. For the optimization in batch reaction, it was found that the fermentation which had the best results was obtained from an inoculum of 0.3 g/L and a initial concentration of total reducing sugars of 50 g/L, resulting in the production of 39.31 g/L of lactic acid and an efficiency of 72.2%. Regarding the fed-batch process, the simulations showed that the best results was obtained from an inoculum of 0.3 g/L with 40 g/L of initial total reducing sugars, with a feed of clarified cashew apple juice at flow rate of 3 L/h and a concentration of 200 g/L, resulting in the production of 38.0 g/L of lactic acid concentration and an efficiency of 63.8%. Therefore, for lactic fermentation using Lactobacillus casei NRRL B-442 and the clarified cashew juice as substrate and the conditions studied in this work, the process in batch was the most advantageous
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Determinación de la actividad antibacteriana "in vitro" del extracto etanólico de la hoja de Erythroxylum novogranatense var truxillense (coca) frente a bacterias orales cariogénicasMinaya Flores, Patricia January 2008 (has links)
El objetivo de la investigación fue determinar la actividad antimicrobiana del extracto de la hoja de Erythroxylum novogranatense var. truxillense frente a bacterias relacionadas directamente con caries dental, a saber Streptococus mutans y Lactobacillus casei. Mediante la técnica de maceración alcohólica, filtrado y evaporación a 40 ˚C del la solución alcohólica, se obtuvo los principios activos totales del Erythroxylum novogranatense var. truxillense. Se utilizó 20 µl de agua destilada y alcohol de 96˚, como control negativo y positivo respectivamente.
Al realizar las pruebas de sensibilidad se obtuvieron los siguientes resultados: Los diámetros de los halos de inhibición para S. mutans tuvieron una media de 34.4mm±2.12mm, y para el caso de L. casei, 33.7mm±3.40mm. Y con respecto a la medida de los halos de inhibición del control negativo y positivo se obtuvo una medida de 00 mm en todos los cultivos para el agua destilada y de 11.4mm±2.12mm en el caso del alcohol a 96°. Encontrándose que éstos difieren en forma estadísticamente significativa al 95% de confianza. Palabras claves: coca, efecto antimicrobiano, Erythroxylum novogranatense var. truxillense, extracto alcohólico, bacterias cariogénicas, Streptococcus mutans, Lactobacillus casei. / The aim of the investigation was to determine the antimicrobial activity of the Erythroxylum novogranatense var. truxillense extract against teeth caries bacteria related, which are Streptococus mutans and Lactobacillus casei. Through an alcoholic oxidation technique, filtered and vapored at 40 ˚C, it was obtained the main actives components of Erythroxylum novogranatense var. truxillense. Sterilized water was used as negative control, and 96˚ alcohol as the positive one.
The disk diffusion method was performed to test antimicrobial activity. The following results were obtained during the performance of the sensibility tests: For S. mutans there was an average inhibiting halo of 34.4mm±2.12mm, and 33.7mm±3.40mm for L. casei. For control inhibition halos (positive and negative) there was an 00 mm in distilled water and 11.4mm±2.12mm for 96° alcohol. This research was made with a 95% of statistics confidence and significant differences were found. Key words: Coca, antimicrobial effect, Erythroxylum novogranatense var. truxillens, Streptococcus mutans, Lactobacillus casei.
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Bactérias ácido lácticas isoladas de silagem de colostro bovino: Potencial probiótico e viabilidade de imobilização celular utilizando como suporte grãos de soja / Lactic acid bacteria isolated from bovine colostrum silage: Probiotic potential and viability of cellular immobilization using as support soybean grainsVitola, Helena Reissig Soares 23 February 2017 (has links)
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Previous issue date: 2017-02-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Bactérias ácido lácticas, com potencial probiótico, são consideradas de grande
interesse para o mercado de alimentos funcionais, os quais estão em expansão,
devido à contribuição desses alimentos à saúde dos indivíduos. Objetivou-se no
presente estudo isolar, caracterizar bactérias acido lácticas com potencial probiótico
e imobilizar em grãos de soja, a fim de manter sua viabilidade durante o
armazenamento. Foram realizados testes para isolamento e caracterização
(coloração de Gram, presença de catalase, propriedades tecnológicas, fermentação
de carboidratos) dos isolados a partir de silagem de colostro bovino; avaliação dos
parâmetros de segurança microbiológica (atividade das enzimas, hemolisina, DNase
e gelatinase, susceptibilidade a antimicrobianos de uso clínico e perfil plasmidial),
avaliação do potencial probiótico (simulação da tolerância ao trânsito
gastrointestinal, capacidade de auto-agregação, co-agregação, hidrofobicidade,
atividade da enzima β galactosidase e atividade antagonista), avaliação da produção
de exopolissacarídeos, identificação molecular, imobilização celular utilizando como
suporte grãos de soja e microscopia eletrônica de varredura do biocatalizador. Dos
isolados caracterizados como bactérias ácido lácticas, seis foram eleitos em testes
preliminares (potencial tecnológico, resistência a diferentes concentrações de bile e
fermentação de açúcares), três apresentaram-se seguros microbiológicamente e um
caracterizou-se como potencialmente probiótico. A bactéria selecionada para
imobilização, SCL3, pertencente ao gênero Lactobacillus da espécie casei,
produtora de exopolissacarídeo, passou por processo fermentativo que permitiu a
adsorção de células na superfície dos grãos de soja. A imobilização possibilitou a
viabilidade das células em concentração de 6,23 log UFC.g
-1
e 6,71 log UFC.g
-1
até
o final do 300
dia de armazenamento após secagem (liofilização) e em refrigeração,
respectivamente. A microscopia eletrônica de varredura permitiu a visualização das
células aderidas a superfície dos grãos de soja. / Lactic acid bacteria, with probiotic potential, are considered of great interest for the
functional food market, which are expanding due to the contribution of these foods to
the health of individuals. The objective of this study was to isolate, characterize lactic
acid bacteria with probiotic potential and immobilize them in soybean grains, in order
to maintain their viability during storage. Isolation and characterization tests (Gram
staining, presence of catalase, technological properties, carbohydrate fermentation)
of the isolates were carried out from bovine colostrum silage; Evaluation of
microbiological safety parameters (enzyme activity, hemolysin, DNase and
gelatinase, susceptibility to antimicrobials of clinical use and plasmid profile),
evaluation of probiotic potential (simulation of gastrointestinal transit tolerance, selfaggregation
capacity, co-aggregation, Hydrophobicity, β-galactosidase enzyme
activity and antagonist activity), evaluation of exopolysaccharide production,
molecular identification, cellular immobilization using as support soybean grains and
scanning electron microscopy of the biocatalyst. Of the isolates characterized as
lactic acid bacteria, six were selected in preliminary tests (technological potential,
resistance to different concentrations of bile and fermentation of sugars), three were
microbiologically safe and one was characterized as potentially probiotic. The
bacterium selected for immobilization, SCL3, belonging to the genus Lactobacillus of
the casei species, exopolysaccharide producer, undergoes a fermentative process
that allowed the adsorption of cells on the surface of the soybean grains. The
immobilization made possible the viability of the cells at a concentration of 6.23 log
CFU.g-1 and 6.71 log CFU.g-1 until the end of the 300 day of storage after drying
(lyophilization) and in refrigeration, respectively. Scanning electron microscopy
allowed the cells to adhere to the surface of the soybean grains.
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