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3.
J Appl Microbiol ; 129(6): 1706-1719, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32320114

RESUMO

AIMS: This study evaluates the action of Weissella paramesenteroides WpK4 on amoebic colitis. METHODS AND RESULTS: Weissella paramesenteroides WpK4 was administered in Entamoeba dispar infected and noninfected mice and clinical parameters were evaluated. Following 7 days, the caeca were collected for histopathology, morphometry and immunohistochemical staining of MUC-2, CDC-47 and IgA. The treatment reduced diarrhoea and the presence of blood in the faeces and diminished the area of necrosis, also causing weight gain. Also, the addition of this bacterium enhanced the expression of the mucin (MUC-2). The reduction in necrosis and increased CDC-47 expression indicates significant epithelial regeneration. The negative correlation between CDC-47 and the necrosis area reveals that the bacterium favoured the recovery of the necrotic regions and the positive correlation found between the expression of MUC-2 and CDC-47 indicates that the epithelial regeneration also supports the synthesis of MUC-2. CONCLUSIONS: Weissella paramesenteroides WpK4 was able to increase the protection of the intestinal mucosa against experimental amoebic colitis through the increase of MUC-2 and epithelial regeneration. SIGNIFICANCE AND IMPACT OF THE STUDY: Weissella paramesenteroides WpK4 presents the potential to become a complementary tool in the treatment of amoebic colitis.


Assuntos
Disenteria Amebiana/prevenção & controle , Mucosa Intestinal/fisiologia , Mucina-2/metabolismo , Regeneração , Weissella/fisiologia , Animais , Modelos Animais de Doenças , Disenteria Amebiana/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/parasitologia , Camundongos , Componente 7 do Complexo de Manutenção de Minicromossomo/metabolismo , Probióticos
4.
J Dairy Sci ; 103(5): 4100-4108, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32197850

RESUMO

Staphylococcus aureus is one of the main causative agents of food poisoning. This bacterium is an important component of cheese microbiota and plays an important role in foodborne diseases. Another important component of the microbiota is the lactic acid bacterium, which actively participates in processes that define the physicochemical, sensorial, and microbiological features of cheese. Of the various microbiological interactions in cheese, the interaction between lactic acid bacteria and Staph. aureus is most relevant. To this end, we evaluated the viability of Staph. aureus strains and the expression of their enterotoxins in cheeses produced experimentally, using Weissella paramesenteroides GIR16L4 or Lactobacillus rhamnosus D1 or both as starter cultures. Over 7 d, we observed that the presence of lactic acid bacteria did not impair Staph. aureus growth. However, via qPCR we observed a change in the gene expression of staphylococcal enterotoxins, suggesting that molecular communication exists between Staph. aureus strains and lactic acid bacteria in cheese.


Assuntos
Toxinas Bacterianas/metabolismo , Queijo/microbiologia , Enterotoxinas/metabolismo , Staphylococcus aureus/crescimento & desenvolvimento , Superantígenos/metabolismo , Weissella/crescimento & desenvolvimento , Animais , Toxinas Bacterianas/genética , Queijo/análise , Enterotoxinas/genética , Microbiologia de Alimentos , Lactobacillales/metabolismo , Leite , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Superantígenos/genética , Transcriptoma , Weissella/metabolismo
5.
J Dairy Sci ; 103(3): 2098-2110, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31980224

RESUMO

Staphylococcus aureus is one of the main pathogens found in cheeses produced with raw milk, including Minas artisanal cheese from Brazil. However, information about S. aureus isolated from artisanal cheeses and its sources of production in small-scale dairies is very limited. We aimed to characterize the virulence factors of S. aureus isolated from raw milk, endogenous starter culture, Minas artisanal cheese, and cheese handlers from the region of Campo das Vertentes, Minas Gerais, Brazil. We identified the staphylococcal isolates by MALDI-TOF mass spectrometry. We evaluated biofilm production on Congo red agar and polystyrene plates. We used PCR to detect icaA, icaB, icaC, sea, seb, sec, sed, see, tsst-1, agr, and mecA. We evaluated the expression of staphylococcal toxin genes in PCR-positive staphylococcal isolates using quantitative reverse-transcription PCR, and we evaluated the production of these toxins and their hemolytic activity in vitro. We also evaluated the antimicrobial resistance profile of the staphylococcal isolates. For statistical analysis, we used cluster analysis, χ2 tests, and correspondence tests. We analyzed 76 staphylococcal isolates. According to PCR, 18.42, 18.42, 2.63, and 77.63% were positive for sea, tsst-1, sec, and agr, respectively. We found low expression of staphylococcal toxin genes according to quantitative reverse-transcription PCR, and only 2 staphylococcal isolates produced toxic shock syndrome toxins. A total of 43 staphylococcal isolates (56.58%) had hemolytic activity; 53 were biofilm-forming on Congo red agar (69.73%), and 62 on polystyrene plates (81.58%). None of the staphylococcal isolates expressed the mecA gene, and none presented a multi-drug resistance pattern. The highest resistance was observed for penicillin G (67.11%) in 51 isolates and for tetracycline (27.63%) in 21 isolates. The staphylococcal isolates we evaluated had toxigenic potential, with a higher prevalence of sea and tsst-1. Biofilm production was the main virulence factor of the studied bacteria. Six clusters were formed whose distribution frequencies differed for hemolytic activity, biofilm formation (qualitative and quantitative analyses), and resistance to penicillin, tetracycline, and erythromycin. These findings emphasize the need for effective measures to prevent staphylococcal food poisoning by limiting S. aureus growth and enterotoxin formation throughout the food production chain and the final product.


Assuntos
Biofilmes/crescimento & desenvolvimento , Queijo/microbiologia , Farmacorresistência Bacteriana , Choque Séptico/microbiologia , Intoxicação Alimentar Estafilocócica/microbiologia , Staphylococcus aureus/genética , Fatores de Virulência , Animais , Antibacterianos/farmacologia , Toxinas Bacterianas/genética , Brasil , Enterotoxinas/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/patogenicidade , Superantígenos/genética
6.
J Appl Microbiol ; 127(4): 1184-1191, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31155822

RESUMO

AIMS: The objective of this study was to assess the probiotic potential of genuine strains of Bifidobacterium longum 51A and Weissella paramesenteroides WpK4, in experimental giardiasis. METHODS AND RESULTS: The bacteria were administered orally to gerbils (Meriones unguiculatus) 10 days before oral infection with trophozoites of Giardia lamblia. After 7 days of infection, the animals were euthanized and portions of the duodenum were processed for histopathologic, histochemical and morphometric assessment. The height of the intestinal crypts and crypt/villi ratio were higher in infected groups (P < 0·05) than in noninfected groups. The area of mucus production was higher (P < 0·05) in infected animals pretreated with B. longum 51A than in other groups. The parasitic load of the animals that received both bacteria decreased significantly (P < 0·05) compared to the ones of the control group. CONCLUSIONS: Our results suggest a probiotic function of B. longum 51A and W. paramesenteroides WpK4 and may result in their use as a prophylactic and therapeutic alternative for promoting human and animal health. SIGNIFICANCE AND IMPACT OF THE STUDY: Bifidobacterium longum 51A and W. paramesenteroides WpK4 may constitute prophylactic alternatives, reversing the emergence of side effects and resistance observed in the conventional treatment of giardiasis.


Assuntos
Bifidobacterium longum , Giardia lamblia/efeitos dos fármacos , Giardíase , Probióticos/farmacologia , Weissella , Animais , Modelos Animais de Doenças , Gerbillinae , Carga Parasitária
7.
Benef Microbes ; 8(4): 579-588, 2017 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-28789560

RESUMO

Ingestion of milks fermented by Lactobacillus strains showing probiotic properties is an important tool to maintain gastrointestinal health. In this study, Lactobacillus rhamnosus D1 and Lactobacillus plantarum B7, isolated from Brazilian artisanal cheese, were used as starters for the functional fermented milks to assess their probiotic properties in a gnotobiotic animal model. Male germ-free Swiss mice received a single oral dose of milk fermented by each sample, and were challenged with Salmonella Typhimurium five days afterwards. Milk fermented by both Lactobacillus strains maintained counts above 108 cfu/ml during cold storage. Lactobacillus strains colonised the gut of the germ-free-mice, maintaining their antagonistic effect. This colonisation led to a protective effect against Salmonella challenge, as demonstrated by reduced pathogen translocation and histological lesions, when compared to control group, especially for Lactobacillus rhamnosus D1. Additionally, mRNA expression of inflammatory (interferon gamma, interleukin (IL)-6, tumour necrosis factor alpha) and anti-inflammatory (transforming growth factor ß1) cytokines was augmented in animals previously colonised and then challenged, when compared to other experimental groups. Lactobacillus plantarum B7 colonisation also promoted higher expression of IL-17, showing a proper maturation of colonised germ-free-mice immune system. IL-5 was stimulated by both strains' colonisation and not by S. Typhimurium challenge.


Assuntos
Queijo/microbiologia , Lactobacillus/metabolismo , Leite/microbiologia , Infecções por Salmonella/prevenção & controle , Salmonella typhimurium/fisiologia , Animais , Brasil , Fermentação , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Humanos , Interferon gama/genética , Interferon gama/imunologia , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-5/genética , Interleucina-5/imunologia , Lactobacillus/isolamento & purificação , Masculino , Camundongos , Infecções por Salmonella/genética , Infecções por Salmonella/imunologia , Infecções por Salmonella/microbiologia , Organismos Livres de Patógenos Específicos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
8.
J Appl Microbiol ; 122(1): 225-238, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27813217

RESUMO

AIMS: The aim of this study was to verify the suitable use of candidate 'probiotics' selected by in vitro tests and the importance of in vivo assays to nominate micro-organisms as probiotics and alternative prophylactic treatments for Salmonella Typhimurium infection. METHODS AND RESULTS: Thirty-three lactic acid bacteria (LAB) isolated from foal's faeces were assessed based on the main desirable functional in vitro criteria. Based on these results, Pediococcus pentosaceus strain 40 was chosen to evaluate its putative probiotic features in a mouse model of Salmonella infection. Daily intragastric doses of Ped. pentosaceus 40 for 10 days before and 10 days after Salmonella challenge (106 CFU of Salm. Typhimurium per mouse) led to a significant aggravation in mouse health by increasing weight loss, worsening clinical symptoms and anticipating the time and the number of deaths by Salmonella. Pediococcus pentosaceus modulated cell-mediated immune responses by up-regulation of the gene expression of the proinflammatory cytokines IFN-γ and TNF-α in the small intestine. CONCLUSION: The usual criteria were used for in vitro screening of a large number of LAB for desirable probiotic functional properties. However, the best candidate probiotic strain identified, Ped. pentosaceus #40, aggravated the experimental disease in mice. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings emphasize the need for prophylactic or therapeutic effectiveness to be demonstrated in in vivo models to make precise health claims.


Assuntos
Fezes/microbiologia , Pediococcus pentosaceus/isolamento & purificação , Probióticos/administração & dosagem , Infecções por Salmonella/tratamento farmacológico , Animais , Citocinas/genética , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Cavalos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pediococcus pentosaceus/genética , Pediococcus pentosaceus/fisiologia , Salmonella/fisiologia , Infecções por Salmonella/genética , Infecções por Salmonella/metabolismo , Infecções por Salmonella/microbiologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
9.
J Dairy Sci ; 99(8): 6086-6096, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27289151

RESUMO

Minas artisanal cheese, produced in the Campo das Vertentes region of Brazil, is made from raw milk and endogenous starter cultures. Although this cheese is of great historical and socioeconomic importance, little information is available about its microbiological and physical-chemical qualities, or about its beneficial microbiota. This work was aimed at evaluating the qualities of the cheese and the components used for its production, comparing samples collected during the dry and rainy seasons. We also conducted molecular identification and isolated 50 samples of lactic acid bacteria from cheese (n=21), water (n=3), raw milk (n=9), and endogenous starter culture (n=17). The microbiological quality of the cheese, water, raw milk, and endogenous starter culture was lower during the rainy period, given the higher counts of coagulase-positive Staphylococcus and total and thermotolerant coliforms. Enterococcus faecalis was the lactic acid bacteria isolated most frequently (42.86%) in cheese samples, followed by Lactococcus lactis (28.57%) and Lactobacillus plantarum (14.29%). Lactobacillus brevis (5.88%), Enterococcus pseudoavium (5.88%), Enterococcus durans (5.88%), and Aerococcus viridans (5.88%) were isolated from endogenous starter cultures and are described for the first time in the literature. The lactic acid bacteria identified in the analyzed cheeses may inhibit undesirable microbiota and contribute to the safety and flavor of the cheese, but this needs to be evaluated in future research.


Assuntos
Queijo/microbiologia , Lactobacillales/isolamento & purificação , Leite/microbiologia , Estações do Ano , Microbiologia da Água , Animais , Brasil , Queijo/análise , Enterococcus/isolamento & purificação , Microbiologia de Alimentos , Ácido Láctico , Lactobacillaceae/isolamento & purificação , Lactobacillus plantarum/isolamento & purificação , Lactococcus lactis/isolamento & purificação , Microbiota , Chuva , Água
11.
Benef Microbes ; 7(1): 61-73, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26565085

RESUMO

Diarrhoea in piglets by Salmonella and other pathogens can be a serious health problem. Non-drug treatments such as probiotic microorganisms have various effects on the gastrointestinal microbiota dysbiosis and host immune system modulation. The aim of this study was to demonstrate the suitable use of Weissella paramesenteroides WpK4 strain isolated from healthy piglets as an alternative prophylactic or therapeutic treatment against Salmonella Typhimurium. Out of 37 lactic acid bacteria isolates, 24 strains belonging to the Weissella and Lactobacillus genera were analysed in vitro for desirable probiotic characteristics. The W. paramesenteroides WpK4 strain fulfilled all in vitro tests: resistance to acidic pH and bile salts, hydrophobic cell surface, antagonism against bacterial pathogens, H2O2 production and exopolysaccharide secretion, and non-transferable resistance to antibiotics. Mice fed with WpK4 showed no signs of bacterial translocation to the liver or spleen and decreased Salmonella translocation to these organs. Significantly, WpK4 intake attenuated the weight loss, fostered the preservation of intestinal architecture and integrity, and promoted survival in mice following infection with Salmonella Typhimurium. In addition, WpK4 modulated immune cellular response by inhibiting the production of pro-inflammatory cytokines and inducing anti-inflammatory mediators. These findings validate the probiotic properties of W. paramesenteroides WpK4 strain, and its eventual use in piglets.


Assuntos
Citocinas/genética , Probióticos/uso terapêutico , Salmonelose Animal/dietoterapia , Suínos/microbiologia , Febre Tifoide/dietoterapia , Weissella , Animais , Peso Corporal , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Expressão Gênica , Imunoglobulina A/biossíntese , Intestinos/imunologia , Intestinos/microbiologia , Masculino , Camundongos , Salmonella typhimurium , Weissella/isolamento & purificação
12.
Arq. bras. med. vet. zootec. (Online) ; 67(2): 636-641, Mar-Apr. 2015. tab
Artigo em Português | VETINDEX | ID: vti-26739

RESUMO

The kinetics of gas production and in vitro ruminal degradation of diets contained replacement of soybean meal (SBM) by detoxicated castorbean meal (DCBM) (0, 15, 30 and 45% of substitution) were evaluated in this study. Values of gas production of non-fibrous carbohydrates (Vf1), fibrous carbohydrates (Vf2) and total carbohydrates (V) showed quadratic behavior, and by observation of equations can be obtained inclusions of 25% the V and Vf1 obtained maximum values of 174.7 and 237.8 ml gas / g DM, respectively. The potential degradability (PD) and effective degradability (ED) of dry matter showed quadratic behavior and by observation of equations can be perceive that up to 18.0% there was an increase in the values of PD and ED that obtained maximum values of 93.7% and 55.7%, respectively. The replacement of SBM by DCBM from 15 to 30% increased the kinetics of gas production and rumen degradation.(AU)


Assuntos
Animais , Ricinus , Rúmen , Inativação Metabólica , Biocombustíveis/toxicidade , Microbiota , Ruminantes/metabolismo , Cinética
13.
Arq. bras. med. vet. zootec ; 67(2): 636-641, Mar-Apr/2015. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1100009

RESUMO

The kinetics of gas production and in vitro ruminal degradation of diets contained replacement of soybean meal (SBM) by detoxicated castorbean meal (DCBM) (0, 15, 30 and 45% of substitution) were evaluated in this study. Values of gas production of non-fibrous carbohydrates (Vf1), fibrous carbohydrates (Vf2) and total carbohydrates (V) showed quadratic behavior, and by observation of equations can be obtained inclusions of 25% the V and Vf1 obtained maximum values of 174.7 and 237.8 ml gas / g DM, respectively. The potential degradability (PD) and effective degradability (ED) of dry matter showed quadratic behavior and by observation of equations can be perceive that up to 18.0% there was an increase in the values of PD and ED that obtained maximum values of 93.7% and 55.7%, respectively. The replacement of SBM by DCBM from 15 to 30% increased the kinetics of gas production and rumen degradation.(AU)


Assuntos
Animais , Ricinus , Rúmen , Inativação Metabólica , Biocombustíveis/toxicidade , Microbiota , Ruminantes/metabolismo , Cinética
14.
Benef Microbes ; 5(4): 471-81, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24902955

RESUMO

Lactic acid bacteria strains are commonly used for animal and human consumption due to their probiotic properties. One of the major genera used is Lactobacillus, a highly diverse genus comprised of several closely related species. The selection of new strains for probiotic use, especially strains of Lactobacillus, is the focus of several research groups. Accurate identification to species level is fundamental for research on new strains, as well as for safety assessment and quality assurance. The 16S-23S internal transcribed spacer (ITS-1) is a deeply homologous region among prokaryotes that is commonly used for identification to the species level because it is able to acquire and accumulate mutations without compromising general bacterial metabolism. In the present study, 16S-23S ITS regions of 45 Lactobacillus species (48 strains) were amplified and subjected to independent enzymatic digestions, using 12 restriction enzymes that recognise six-base sequences. Twenty-nine species showed unique restriction patterns, and could therefore be precisely identified solely by this assay (64%). This approach proved to be reproducible, allowing us to establish simplified restriction patterns for each evaluated species. The restriction patterns of each species were similar among homologous strains, and to a large extent reflected phylogenetic relationships based on 16S rRNA sequences, demonstrating the promising nature of this region for evolutionary studies.


Assuntos
Técnicas Bacteriológicas/métodos , Lactobacillus/classificação , Lactobacillus/genética , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Reprodutibilidade dos Testes
15.
Benef Microbes ; 5(4): 409-19, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24939801

RESUMO

The effect of intestinal colonisation on the immune system was investigated in germ-free mice monoassociated with Lactobacillus strains isolated from calf faeces. Single doses of Lactobacillus acidophilus L36 or Lactobacillus salivarius L38 were administered to germ-free mice by intragastric gavage. Ten days later, the mice were euthanised. Gene expression levels of interleukin 5 (IL-5), IL-6, IL-10, IL-12b, IL-17a, gamma interferon (IFN-γ), transforming growth factor beta 1 (TGF-ß1), and tumour necrosis factor alpha (TNF-α) were quantified in segments of the small and large intestines by real time quantitative polymerase chain reaction. All the mice were colonised rapidly after Lactobacillus administration with intestinal counts ranging from 6.53 to 8.26 log cfu/g. L. acidophilus L36 administration increased the expression of cytokines involved with the Th2 (IL-5, IL-6 and TGF-ß1) and Th17 (IL-17a, TNF-α and IL-6) inflammatory response, whereas L. salivarius L38 appeared to stimulate a pattern of less diversified cytokines in the intestine. Intragastric gavage of L. acidophilus L36 and L. salivarius L38 induced similar levels of colonisation in the digestive tracts of germ-free mice but stimulated different immune responses in the intestinal mucosa. The different immunomodulation patterns might facilitate the potential use of these lactobacilli as probiotics to treat distinct pathological conditions, for example protection against Citrobacter rodentium infection by stimulating IL-17 production.


Assuntos
Citocinas/biossíntese , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Vida Livre de Germes , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/imunologia , Animais , Carga Bacteriana , Citocinas/genética , Perfilação da Expressão Gênica , Camundongos , Reação em Cadeia da Polimerase em Tempo Real
16.
Arq. bras. med. vet. zootec ; 66(3): 940-948, 06/2014. tab
Artigo em Inglês | VETINDEX | ID: vti-10831

RESUMO

Lactic acid bacteria species were molecularly identified in milk from Lacaune, Santa Inês and crossbred sheep breeds and their in vitro probiotic potential was evaluated. The species identified were Enterococcus faecium (56.25%), E. durans (31.25%) and E. casseliflavus (12.5%). No other lactic acid bacteria species, such as lactobacilli, was identified. Most of the isolated enterococci were resistant to gastric pH (2.0) and to 0.3% oxgall. All tested enterococci were resistant to ceftazidime, oxacillin and streptomycin and sensible to clindamycin, erythromycin and penicillin. The resistance to ciprofloxacin, gentamicin, tetracycline and vancomycin varied among tested species. All tested enterococci strongly inhibited (P<0.05) Escherichia coli and Listeria monocytogenes, moderately inhibited E. faecalis and Staphylococcus aureus and did not inhibit Pseudomonas aeruginosa, Salmonella enterica var. Typhimurium and also one E. durans sample isolated from sheep milk. Four samples of E. faecium, one of E. durans and one of E. casseliflavus presented the best probiotic potential.(AU)


Espécies de bactérias ácido-lácticas foram identificadas em nível molecular em leite das raças ovinas Lacaune, Santa Inês e suas mestiças, e o seu potencial probiótico in vitro foi avaliado. As espécies identificadas foram Enterococcus faecium (56,25%), E. durans (31,25%) e E. casseliflavus (12,5%). Nenhuma outra espécie de bactéria ácido-láctica, como Lactobacillus sp., foi identificada. A maioria dos enterococos isolados foi resistente ao pH gástrico (2.0) e a 0,3% de oxgall. Todos os enterococos testados foram resistentes à ceftazidima, oxacilina e estreptomicina e sensíveis à clindamicina, eritromicina e penicilina. A resistência à ciprofloxacina, gentamicina, tetraciclina e vancomicina variou entre as amostras. Todos os enterococos testados inibiram fortemente (P<0,05) Escherichia coli e Listeria monocytogenes, inibiram moderadamente E. faecalis e Staphylococcus aureus e não inibiram Pseudomonas aeruginosa, Salmonella enterica var. Typhimurium e uma amostra de E. durans isolada de leite de ovelha. Quatro amostras de E. faecium, uma de E. durans e uma de E. casseliflavus apresentaram o melhor potencial probiótico.(AU)


Assuntos
Animais , Feminino , Ovinos/microbiologia , Ácido Láctico/análise , Enterococcus faecium/isolamento & purificação , Enterococcus/isolamento & purificação , Oxacilina/isolamento & purificação , Estreptomicina/isolamento & purificação , Resistência a Medicamentos , Farmacorresistência Bacteriana Múltipla
17.
Arq. bras. med. vet. zootec ; 66(3): 940-948, 06/2014. tab
Artigo em Inglês | LILACS | ID: lil-718096

RESUMO

Lactic acid bacteria species were molecularly identified in milk from Lacaune, Santa Inês and crossbred sheep breeds and their in vitro probiotic potential was evaluated. The species identified were Enterococcus faecium (56.25%), E. durans (31.25%) and E. casseliflavus (12.5%). No other lactic acid bacteria species, such as lactobacilli, was identified. Most of the isolated enterococci were resistant to gastric pH (2.0) and to 0.3% oxgall. All tested enterococci were resistant to ceftazidime, oxacillin and streptomycin and sensible to clindamycin, erythromycin and penicillin. The resistance to ciprofloxacin, gentamicin, tetracycline and vancomycin varied among tested species. All tested enterococci strongly inhibited (P<0.05) Escherichia coli and Listeria monocytogenes, moderately inhibited E. faecalis and Staphylococcus aureus and did not inhibit Pseudomonas aeruginosa, Salmonella enterica var. Typhimurium and also one E. durans sample isolated from sheep milk. Four samples of E. faecium, one of E. durans and one of E. casseliflavus presented the best probiotic potential...


Espécies de bactérias ácido-lácticas foram identificadas em nível molecular em leite das raças ovinas Lacaune, Santa Inês e suas mestiças, e o seu potencial probiótico in vitro foi avaliado. As espécies identificadas foram Enterococcus faecium (56,25%), E. durans (31,25%) e E. casseliflavus (12,5%). Nenhuma outra espécie de bactéria ácido-láctica, como Lactobacillus sp., foi identificada. A maioria dos enterococos isolados foi resistente ao pH gástrico (2.0) e a 0,3% de oxgall. Todos os enterococos testados foram resistentes à ceftazidima, oxacilina e estreptomicina e sensíveis à clindamicina, eritromicina e penicilina. A resistência à ciprofloxacina, gentamicina, tetraciclina e vancomicina variou entre as amostras. Todos os enterococos testados inibiram fortemente (P<0,05) Escherichia coli e Listeria monocytogenes, inibiram moderadamente E. faecalis e Staphylococcus aureus e não inibiram Pseudomonas aeruginosa, Salmonella enterica var. Typhimurium e uma amostra de E. durans isolada de leite de ovelha. Quatro amostras de E. faecium, uma de E. durans e uma de E. casseliflavus apresentaram o melhor potencial probiótico...


Assuntos
Animais , Feminino , Ácido Láctico/análise , Ceftazidima/isolamento & purificação , Enterococcus faecium/isolamento & purificação , Enterococcus/isolamento & purificação , Estreptomicina/isolamento & purificação , Ovinos/microbiologia , Oxacilina/isolamento & purificação , Resistência a Medicamentos , Farmacorresistência Bacteriana Múltipla
18.
Arq. bras. med. vet. zootec ; 66(1): 93-100, fev. 2014. ilus
Artigo em Inglês | LILACS | ID: lil-704011

RESUMO

Lactobacillus spp. isolated from different portions of chickens' gastrointestinal tract were evaluated concerning their ability to survive in a water-in-oil (W/0) emulsion containing sesame and sunflower oil. After sixty days of emulsion storage under refrigeration, three of five strains tested survived in number equal to or higher than 10(6)cfu/g. Lactobacillus reuteri 2M14C, which presented the highest survival in W/O emulsion (10(7)cfu/g), was tested for its capacity to resist throughout the passage through gnotobiotic mice gastrointestinal tract and for the ability to stimulate murine peritoneal macrophages phagocytosis. This strain remained at a number above 10(9)cfu/g feces during ten days of monoassociation, and monoassociated mice showed phagocytic activity significantly greater than the germ-free controls (P<0.05). The results suggest that the formulation can be used to incorporate viable Lactobacillus spp. cells in animal feed. Moreover, the results suggest that L. reuteri 2M14C is a strong candidate to be incorporated in probiotic formulations for use in chicken.


Lactobacillus spp. isolados de diferentes porções do trato gastrintestinal de frangos foram testados quanto à capacidade de se manterem viáveis em uma emulsão água/óleo (A/O) contendo óleos de gergelim e de girassol. Após sessenta dias de estocagem sob refrigeração, três de cinco linhagens testadas sobreviveram em concentração igual ou superior a 10 6 UFC/g. Lactobacillus reuteri 2M14C, que apresentou maior capacidade de sobrevivência na emulsão desenvolvida (10 7 UFC/g), foi testado quanto à sua capacidade de sobreviver às condições do trato gastrintestinal in vivo em camundongos gnotobióticos. Após dez dias de monoassociação com L. reuteri 2M14C, foi testada também a capacidade de estimulação da atividade fagocítica de macrófagos peritoneais. A linhagem permaneceu em número superior a 10 9 UFC/g de conteúdo fecal durante os dez dias de monoassociação, e os camundongos monoassociados apresentaram atividade fagocítica maior (P<0,05) que a do grupo controle isento de germe. Os resultados sugerem que a formulação proposta é capaz de manter a viabilidade de células de lactobacilos para adição em ração animal, necessitando, no entanto, de um acompanhamento dessa viabilidade por tempo maior de estocagem. Além disso, os resultados demonstram que Lactobacillus reuteri 2M14C é um forte candidato a ser adicionado em formulações probióticas para uso em frangos.


Assuntos
Animais , Lactobacillus , Fagocitose , Probióticos/análise , Trato Gastrointestinal/anatomia & histologia , Galinhas/classificação
19.
Arq. bras. med. vet. zootec ; 66(1): 93-100, Feb. 2014. ilus
Artigo em Inglês | VETINDEX | ID: vti-10311

RESUMO

Lactobacillus spp. isolated from different portions of chickens' gastrointestinal tract were evaluated concerning their ability to survive in a water-in-oil (W/0) emulsion containing sesame and sunflower oil. After sixty days of emulsion storage under refrigeration, three of five strains tested survived in number equal to or higher than 10(6)cfu/g. Lactobacillus reuteri 2M14C, which presented the highest survival in W/O emulsion (10(7)cfu/g), was tested for its capacity to resist throughout the passage through gnotobiotic mice gastrointestinal tract and for the ability to stimulate murine peritoneal macrophages phagocytosis. This strain remained at a number above 10(9)cfu/g feces during ten days of monoassociation, and monoassociated mice showed phagocytic activity significantly greater than the germ-free controls (P<0.05). The results suggest that the formulation can be used to incorporate viable Lactobacillus spp. cells in animal feed. Moreover, the results suggest that L. reuteri 2M14C is a strong candidate to be incorporated in probiotic formulations for use in chicken.(AU)


Lactobacillus spp. isolados de diferentes porções do trato gastrintestinal de frangos foram testados quanto à capacidade de se manterem viáveis em uma emulsão água/óleo (A/O) contendo óleos de gergelim e de girassol. Após sessenta dias de estocagem sob refrigeração, três de cinco linhagens testadas sobreviveram em concentração igual ou superior a 10 6 UFC/g. Lactobacillus reuteri 2M14C, que apresentou maior capacidade de sobrevivência na emulsão desenvolvida (10 7 UFC/g), foi testado quanto à sua capacidade de sobreviver às condições do trato gastrintestinal in vivo em camundongos gnotobióticos. Após dez dias de monoassociação com L. reuteri 2M14C, foi testada também a capacidade de estimulação da atividade fagocítica de macrófagos peritoneais. A linhagem permaneceu em número superior a 10 9 UFC/g de conteúdo fecal durante os dez dias de monoassociação, e os camundongos monoassociados apresentaram atividade fagocítica maior (P<0,05) que a do grupo controle isento de germe. Os resultados sugerem que a formulação proposta é capaz de manter a viabilidade de células de lactobacilos para adição em ração animal, necessitando, no entanto, de um acompanhamento dessa viabilidade por tempo maior de estocagem. Além disso, os resultados demonstram que Lactobacillus reuteri 2M14C é um forte candidato a ser adicionado em formulações probióticas para uso em frangos.(AU)


Assuntos
Animais , Trato Gastrointestinal/anatomia & histologia , Lactobacillus , Probióticos/análise , Fagocitose , Galinhas/classificação
20.
Arq. bras. med. vet. zootec ; 65(6): 1858-1866, dez. 2013. tab
Artigo em Português | VETINDEX | ID: vti-10131

RESUMO

O potencial probiótico in vitro de 12 amostras de bactérias ácido-láticas (11 Lactobacillus spp. e uma Weissella paramesenteroides), isoladas de queijo-de-minas artesanal da Serra da Canastra, foi investigado. Essas amostras foram caracterizadas in vitro quanto à susceptibilidade a antimicrobianos, antagonismo contra microrganismos de referência patogênicos e não patogênicos e sensibilidade a pH gástrico e sais biliares. Apenas L. rhamnosus B4, W. paramesenteroides C10 e L. rhamnosus D1 apresentaram resistência a menor número de antimicrobianos (ceftazidima, oxacilina, estreptomicina e vancomicina). Todas as amostras apresentaram atividade antagonista frente a todas as bactérias patogênicas testadas e não inibiram as bactérias não patogênicas. Todas as amostras foram resistentes ao pH gástrico (2.0). Alguns microrganismos mostraram pouca inibição do crescimento em presença de sais biliares, enquanto outros foram moderadamente ou altamente inibidos. L. rhamnosus B4, W. paramesenteroides C10 e L.rhamnosus D1 apresentaram o melhor potencial probiótico de acordo com os testes in vitro realizados.(AU)


The in vitro probiotic potential of twelve samples of lactic acid bacteria (eleven Lactobacillus spp. and one Weissella paramesenteroides) isolated from Minas artisanal cheese from Serra da Canastra was evaluated for their antimicrobial susceptibility, antagonistic activity against pathogenic and lactic acid bacteria, as well as for their tolerance to gastric pH and biliary salts. Only L. rhamnosus B4, W. paramesenteroides C10, and L. rhamnosus D1 showed resistance to tested antimicrobials (ceftazidime, oxacillin, streptomycin, and vancomycin). All samples showed antagonism against all pathogenic bacteria tested and did not inhibit the growth of nonpathogenic samples. Regarding gastric pH tolerance, all samples showed low inhibition at pH 2. The tolerance to biliary salts varied from low to great among tested samples. L. rhamnosus B4, W. paramesenteroides C10, and L. rhamnosus D1 showed the best probiotic potential revealed by their in vitro test results.(AU)


Assuntos
Animais , Noxas/análise , Ácido Láctico/análise , Queijo , Probióticos , Bactérias
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