297 resultados para Lactobacillus acidophilus

em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Escherichia coli faz parte da microbiota anaeróbica facultativa normal, sendo também considerada um dos maiores patógenos entéricos predominantes no cólon dos animais e homem. Neste trabalho, realizaram-se ensaios in vitro para avaliar o grau de atividade antagonista de cinco cepas de Lactobacillus acidophilus, com capacidade probiótica sobre Escherichia coli BIA 26 (STEC) isolada de queijo Minas Frescal. Para tanto, foi utilizado o teste de inibição através do método de dupla camada em triplicata para avaliar zonas de inibição de crescimento. Todas as cepas de Lactobacillus mostraram-se capazes de inibir a E. coli, com zonas de inibição variando de 12 a 15mm de diâmetro, sendo que a maioria apresentou 14mm de diâmetro, consideradas como fortes halos de inibição.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The production of antimicrobial compounds of some strains of Lactobacillus acidophilus has been studied. They have been grown in whey supplemented with soy milk. It has been found that the production of compounds is able to inhibit the growing of both target bacteria analysed: Staphylococcus aureus and Escherichia coli. The results showed a significant variation (p>0.05) depending on the strain of L. acidophilus and on the level of supplementation utilized. Most of the inhibition observed resulted from the presence of the lactic acid produced. It has also been found the production of other antimicrobial compounds showing inhibitory capacity. The action of these compounds was influenced by the substract pH.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The antimicrobial activity of a commercial probiotic culture, Lactobacillus acidophilus (La5), was tested against two foodborne pathogens, Escherichia coli and Staphylococcus aureus. The antagonistic effect of the probiotic culture in vitro was performed by applying both Multilayer Agar Plate and Agar Well Diffusion methods. The results indicated that the inhibitory substance present on 72 hours culture broth supernatant was extracellular and diffusible. The incubation period of the lactic acid bacteria on MRS Broth, at 3 7 degrees C in aerobic conditions, for the highest lactic acid production (1,08 g/%) was 72 hours, which gave a minimum pH value of the supernatant (3,90) and the best inhibition results by the Well Diffusion Agar Assay, showing inhibition zone diameters of 14,75mm and 15,0mm for E. coli and S. aureus, respectively. The inhibitor compound was not sensitive to proteolytic enzyme and freezing, but was totally inactivated when the supernatant was neutralized with NaOH 1 N solution. The results suggest that the inhibitory activity was due to the lactic acid concentration and the low pH of the probiotic culture broth.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Whey supplemented with soy milk has been used as a low-cost alternative in the growth of Lactobacillus acidophilus for the production of antimicrobial compounds. Response Surface Metodology has been employed in order to study the effects of initial pH, incubation temperature and soy milk rate for supplementation in the production of antimicrobial substance. It has been observed that both tested microrganisms used (S. aureus and E. coli) were inhibited by antimicrobial substance produced by L. acidophilus. The results obtained with E. coli inhibition did not follow the employed statistical model. on the other hand, when the tested microorganism S. aureus was used, the best inhibition results have been obtained when L. acidophilus was incubated at 36.80 degrees C in whey with 5.6 initial pH and 31,90% (v/v) rate supplemented with soy milk. The analysed antimicrobial substances were nor acids neither hidrogen peroxid.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: How to maintain gut health is a goal for scientists throughout the world. Therefore, microbiota management models for testing probiotics, prebiotics, and synbiotics have been developed.Methods: The SHIME® model was used to study the effect of Lactobacillus acidophilus 1014 on the fermentation pattern of the colon microbiota. Initially, an inoculum prepared from human feces was introduced into the reactor vessels and stabilized over 2-wk using a culture medium. This stabilization period was followed by a 2-wk control period during which the microbiota was monitored. The microbiota was then subjected to a 4-wk treatment period by adding 5 mL of sterile peptone water with L. acidophilus CRL1014 at the concentration of 108 CFU/mL to vessel one (the stomach compartment). Plate counts, Denaturing Gradient Gel Electrophoresis (DGGE), short-chain fatty acid (SCFA) and ammonium analyses were carried out for monitoring of the microbial community from the colon compartments.Results: A significant increase (p < 0.01) in the Lactobacillus spp. and Bifidobacterium spp. populations was observed during the treatment period. The DGGE obtained showed changes in the lactobacilli community from the colon compartments of the SHIME® reactor. The (SCFA) concentration increased (p < 0.01) during the treatment period, due mainly to significant increased levels of acetic, butyric, and propionic acids. However, ammonium concentrations decreased during the same period (p < 0.01).Conclusions: This study showed the beneficial influence of L. acidophilus CRL 1014 on microbial metabolism and lactobacilli community composition for improving human health. © 2013 Sivieri et al.; licensee BioMed Central Ltd.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Microparticles with high protein content can be used as diets to mimic the proximate composition of Artemia nauplii. After production, the particles were characterized with respect to their proximate composition, mean size, morphology, and rehydration behavior after drying. The protein content, lipid content and the particle moisture were similar to Artemia nauplii, with mean values of 50, 23, and 85%, respectively. Additionally, the particles were used in a pacu (Piaractus mesopotamicus) larval growth experiment. Also, the probiotic Lactobacillus acidophilus was added to one of the diets, and the effects of the diets were evaluated on larvae growth and stress resistance. Larvae fed the experimental diets had lower growth than larvae fed with Artemia nauplii or a commercial diet. All of the evaluated diets, including the experimental ones, showed high ingestion rates (>90%). In the stress test by air exposure, larvae fed with the microparticle without probiotic exhibited a significantly higher mortality than those fed the commercial diet or those fed with Artemia nauplii. The low growth rates may have been due to a potential nutritional inadequacy with respect to the low mineral/vitamin content of the experimental diets. (C) 2014 Elsevier Ltd. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Os micro-organismos probióticos são utilizados em vários produtos alimentícios ou em suplementos alimentares. Simuladores intestinais representam uma opção de realização de estudos com a microbiota intestinal. O simulador do ecossistema microbiano humano (SEMH) consiste em uma sucessão de cinco reatores conectados que representam as diferentes partes do trato gastrointestinal humano com seus respectivos valores de pH, tempo de residência e capacidade volumétrica. O SEMH foi utilizado para estudar o efeito do Enterococcus faecium CRL 183 e do Lactobacillus acidophilus CRL 1014 sobre a microbiota intestinal nativa. Inicialmente, o inóculo preparado com fezes humanas foi introduzido nos três reatores, responsáveis por simular o cólon ascendente, transverso e descendente. Após duas semanas de estabilização foi adicionado, diariamente, durante quatro semanas, E. faecium CRL 183 e L. acidophilus CRL 1014 contendo 108 UFC/mL nos três compartimentos que simulam o cólon ascendente, transverso e descendente. Após as quatro semanas de tratamento o sistema permaneceu durante duas semanas sem adição de probióticos. Durante todo o experimento, foi realizado semanalmente a composição da microbiota intestinal baseada na enumeração de bactérias aeróbias e anaeróbias totais, Enterococcus spp., Lactobacillus spp., Bifidobacterium spp., Enterobactérias e Clostridium spp. Semanalmente, também, foram realizadas análises de ácidos graxos de cadeia curta (acetato, butirato e propionato) e amônia. Através da análise microbiológica observou-se alterações significativas na composição da microbiota do SEMH no decorrer do período do experimento. Alterações significativas também foram observadas na concentração de amônia e de AGCC, podendo assim observar a influência da inoculação de probióticos na microbiota nativa e os metabólitos produzidos por ela

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Maintaining the viability of probiotic microorganisms from production to consumption has long been a technological challenge for the food industry. The objectives of this study were to evaluate the in vitro interaction between Lactobacillus acidophilus La-5 and Williopsis saturnus var. suaveolens and the effect of this yeast on acidification kinetics, viability of Lactobacillus acidophilus and post-acidification in fermented milk during refrigerated storage at 5 °C. The in vitro study showed a positive interaction between the acid cell free-supernatant (CFS) of probiotic bacteria La-5 and the yeast. The addition of W. saturnus var. suaveolens increased the fermentation time due to consumption of the organic acids produced by L. acidophilus. During the refrigerated storage of the samples, the presence of the yeast increased the viability of L. acidophilus and reduced post-acidification. However, the mechanism of such interaction of bacteria and yeast is not fully understood.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)