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1.
Molecules ; 24(20)2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31640295

RESUMO

Two by-products containing phenols and polysaccharides, a "pâté" (OP) from the extra virgin olive oil milling process and a decoction of pomegranate mesocarp (PM), were investigated for their effects on human microbiota using the SHIME® system. The ability of these products to modulate the microbial community was studied simulating a daily intake for nine days. Microbial functionality, investigated in terms of short chain fatty acids (SCFA) and NH4+, was stable during the treatment. A significant increase in Lactobacillaceae and Bifidobacteriaceae at nine days was induced by OP mainly in the proximal tract. Polyphenol metabolism indicated the formation of tyrosol from OP mainly in the distal tract, while urolithins C and A were produced from PM, identifying the human donor as a metabotype A. The results confirm the SHIME® system as a suitable in vitro tool to preliminarily investigate interactions between complex botanicals and human microbiota before undertaking more challenging human studies.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Olea/química , Fenóis/administração & dosagem , Polissacarídeos/administração & dosagem , Romã (Fruta)/química , Compostos de Amônio/metabolismo , Bifidobacterium/classificação , Bifidobacterium/efeitos dos fármacos , Bifidobacterium/isolamento & purificação , DNA Bacteriano/análise , Ácidos Graxos Voláteis/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactobacillaceae/classificação , Lactobacillaceae/efeitos dos fármacos , Lactobacillaceae/isolamento & purificação , Fenóis/química , Fenóis/farmacologia , Filogenia , Polissacarídeos/química , Polissacarídeos/farmacologia
2.
Food Microbiol ; 76: 267-278, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30166150

RESUMO

Mawè is a West African spontaneous fermented cereal-based dough. Different types of mawè exist varying in type of cereal and/or production condition, with fermentations lasting 24-48 h. With the aim of obtaining a comprehensive understanding of the microbial ecology of mawè processing, a microbiological characterisation was performed for four mawè types, produced at eight sites in Benin. At the onset of the fermentations lactic acid bacteria (LAB) and yeast counts were on average 7.5 ±â€¯1.03 and 4.8 ±â€¯0.79 Log10 cfu/g, which increased to 9.2 ±â€¯0.38 and 7.4 ±â€¯0.42 Log10 cfu/g, respectively, at the end of the fermentations. LAB (n = 321) and yeasts (n = 298), isolated during the fermentations, were identified. The predominant LAB and yeast species were Lactobacillus fermentum and Pichia kudriavzevii, respectively, followed by Kluyveromyces marxianus, all present throughout the mawè fermentations. Further, microbial successions took place with Weissella confusa occurring mostly at the onset, while Pediococcus acidilactici and Saccharomyces cerevisiae were mainly associated with the end of the fermentations. Species diversity was influenced both by type of cereal and production condition. The dominating strain clusters of L. fermentum and P. kudriavzevii were ubiquitous and strain diversities were influenced by type of cereal and production site.


Assuntos
Grão Comestível/microbiologia , Fermentação , Alimentos e Bebidas Fermentados/microbiologia , Lactobacillaceae/isolamento & purificação , Leveduras/isolamento & purificação , Candida/isolamento & purificação , Candida/metabolismo , Microbiologia de Alimentos , Ácido Láctico/análise , Lactobacillaceae/classificação , Lactobacillaceae/metabolismo , Lactobacillus fermentum/isolamento & purificação , Pichia/isolamento & purificação , Pichia/metabolismo , Saccharomyces cerevisiae/isolamento & purificação , Saccharomyces cerevisiae/metabolismo , Leveduras/classificação , Leveduras/metabolismo
3.
Molecules ; 23(5)2018 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-29751655

RESUMO

Bile salt hydrolase (BSH) is a well-known enzyme that has been commonly characterized in probiotic bacteria, as it has cholesterol-lowering effects. However, its molecular investigations are scarce. Here, we build a local database of BSH sequences from Lactobacillaceae (BSH⁻SDL), and phylogenetic analysis and homology searches were employed to elucidate their comparability and distinctiveness among species. Evolutionary study demonstrates that BSH sequences in BSH⁻SDL are divided into five groups, named BSH A, B, C, D and E here, which can be the genetic basis for BSH classification and nomenclature. Sequence analysis suggests the differences between BSH-active and BSH-inactive proteins clearly, especially on site 82. In addition, a total of 551 BSHs from 107 species are identified from 451 genomes of 158 Lactobacillaceae species. Interestingly, those bacteria carrying various copies of BSH A or B can be predicted to be potential cholesterol-lowering probiotics, based on the results of phylogenetic analysis and the subtypes that those previously reported BSH-active probiotics possess. In summary, this study elaborates the molecular basis of BSH in Lactobacillaceae systematically, and provides a novel methodology as well as a consistent standard for the identification of the BSH subtype. We believe that high-throughput screening can be efficiently applied to the selection of promising candidate BSH-active probiotics, which will advance the development of healthcare products in cholesterol metabolism.


Assuntos
Amidoidrolases/genética , Amidoidrolases/metabolismo , Genoma Bacteriano , Genômica , Lactobacillaceae/enzimologia , Lactobacillaceae/genética , Amidoidrolases/química , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Domínio Catalítico , Ativação Enzimática , Genômica/métodos , Lactobacillaceae/classificação , Filogenia
4.
Food Microbiol ; 70: 143-154, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29173621

RESUMO

Nicastrese goat's cheese is produced in the South of Italy under traditional procedures, from raw goat milk without any starter cultures addition. Samples from milk to ripened cheese provided by 4 different farms were subjected to a polyphasic approach to study their physico-chemical, microbiological and sensorial characteristics. In addition, volatile organic compounds formation in the final products was studied. Overall, gross composition and microbiological data revealed a significant variability among samples, which was confirmed by both the volatile organic compounds generated in the final products and by the sensorial data. Conventional technique allowed us to identify 720 isolates, mainly belonging to Lactococcus lactis, Lactobacillus plantarum, Lactobacillus casei, Lactobacillus brevis, Leuconostoc mesenteroides, and Enterococcus faecalis. Culture-independent methods revealed shifts in the microbial community structure, with an increase in biodiversity of metabolically active bacterial species, from milk to cheese samples. Analysis of volatile organic compounds (VOCs) allowed the identification of 36 compounds; free fatty acids and ketones represented the main detected, followed by alcohols and esters. Moreover, statistical analysis was performed in order to correlate VOCs to bacterial species. Data showed that ester compounds as well as alcohol and aldehydes were positively correlated to NSLAB, indicating that the occurrence of L. casei, L. plantarum and L. brevis species is relevant for the VOCs formation in the final product.


Assuntos
Queijo/microbiologia , Lactobacillaceae/isolamento & purificação , Animais , Biodiversidade , Queijo/análise , Fermentação , Cabras , Itália , Lactobacillaceae/classificação , Lactobacillaceae/genética , Lactobacillaceae/metabolismo , Leite/química , Leite/microbiologia , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
5.
Food Microbiol ; 63: 178-190, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28040167

RESUMO

A total of 114 lactic acid bacteria were isolated at one and 21 days of ripening from a traditional raw cow's milk cheese without the addition of starter culture, produced by three artisanal cheese-makers in Azores Island (Pico, Portugal). Identification to species and strain level was accomplished by16S rRNA gene and PFGE analysis. Carbohydrate utilization profiles were obtained with the relevant API kits. Isolates were evaluated according to safety and technological criteria. The most frequently observed genus identified by 16S rRNA sequencing analysis was Enterococcus, whereas API system mostly identified Lactobacillus. The highest percentages of antibiotic resistance were to nalidixic acid (95%), and aminoglycosides (64-87%). All isolates were sensitive to several beta-lactam antibiotics and negative for histamine and DNase production. Gelatinase activity was detected in 49.1% of isolates, 43% were able to degrade casein and 93% were α-hemolytic. Most enterococci presented virulence genes, such as gelE, asaI, ace. Diacetyl production was found to be species dependent and one strain (Leu. citreum) produced exopolysaccharides. Selected strains were further studied for technological application and were found to be slow acid producers in milk and experimental cheeses, a desirable trait for adjunct cultures. Two strains were selected on the basis of technological and safety application as adjunct cultures in cheese production and presented the best cheese aroma and flavor in consumer preference tests. This is the first effort to characterize Pico cheese LAB isolates for potential application as adjunct cultures; the results suggest the potential of two strains to improve the quality of this traditional raw milk product.


Assuntos
Queijo/microbiologia , Inocuidade dos Alimentos , Variação Genética , Lactobacillaceae/genética , Alimentos Crus/microbiologia , Animais , Antibacterianos/farmacologia , Bovinos , Farmacorresistência Bacteriana Múltipla , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Enterococcus/isolamento & purificação , Microbiologia de Alimentos , Qualidade dos Alimentos , Lactobacillaceae/classificação , Lactobacillaceae/isolamento & purificação , Lactobacillus/efeitos dos fármacos , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Portugal , RNA Ribossômico 16S , Paladar , Vancomicina/farmacologia , Virulência/genética
6.
Gut Microbes ; 8(4): 311-322, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28080206

RESUMO

The existence of an implicit living microscopic world, composed primarily of bacteria, has been known for centuries. The exact mechanisms that govern the contribution of bacteria to human health and disease have only recently become the subject of intense research efforts. Within this very evident shift in paradigms, the rational design of probiotic formulations has led to the creation of an industry that seeks to progress the engineering of probiotic bacteria that produce metabolites that may enhance human host health and prevent disease. The promotion of probiotics is often made in the absence of quality scientific and clinically plausible data. The latest incursions into the probiotic market of claims have posited the amelioration of oxidative stress via potent antioxidant attributes or limiting the administration of probiotics to those species that do not produce D-Lactic acid (i.e., claims that D-Lactic acid acidosis is linked to chronic health conditions) or are strain-specific (shaping an industry point of difference) for appraising a therapeutic effect. Evidence-based research should guide clinical practice, as there is no place in science and medicine that supports unsubstantiated claims. Extravagant industry based notions continue to fuel the imprimatur of distrust and skepticism that is leveled by scientists and clinicians at an industry that is already rife with scientific and medical distrust and questionable views on probiotics. Ignoring scientifically discordant data, when sorting through research innovations and false leads relevant to the actions of probiotics, drives researcher discomfit and keeps the bar low, impeding the progress of knowledge. Biologically plausible posits are obligatory in any research effort; companies formulating probiotics often exhibit a lack of analytical understanding that then fuels questionable investigations failing to build on research capacity.


Assuntos
Acidose Láctica/tratamento farmacológico , Lactobacillaceae/fisiologia , Estresse Oxidativo , Probióticos/análise , Acidose Láctica/metabolismo , Animais , Humanos , Lactobacillaceae/classificação , Especificidade da Espécie
7.
Food Microbiol ; 62: 15-22, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27889142

RESUMO

Entomophagy has been linked to nutritional, economic, social and ecological benefits. However, scientific studies on the potential safety risks in eating edible insects need to be carried out for legislators, markets and consumers. In this context, the microbiota of edible insects deserves to be deeply investigated. The aim of this study was to elucidate the microbial species occurring in some processed marketed edible insects, namely powdered small crickets, whole dried small crickets (Acheta domesticus), whole dried locusts (Locusta migratoria), and whole dried mealworm larvae (Tenebrio molitor), through culture-dependent (classical microbiological analyses) and -independent methods (pyrosequencing). A great bacterial diversity and variation among insects was seen. Relatively low counts of total mesophilic aerobes, Enterobacteriaceae, lactic acid bacteria, Clostridium perfringens spores, yeasts and moulds in all of the studied insect batches were found. Furthermore, the presence of several gut-associated bacteria, some of which may act as opportunistic pathogens in humans, were found through pyrosequencing. Food spoilage bacteria were also identified, as well as Spiroplasma spp. in mealworm larvae, which has been found to be related to neurodegenerative diseases in animals and humans. Although viable pathogens such as Salmonella spp. and Listeria monocytogenes were not detected, the presence of Listeria spp., Staphylococcus spp., Clostridium spp. and Bacillus spp. (with low abundance) was also found through pyrosequencing. The results of this study contribute to the elucidation of the microbiota associated with edible insects and encourage further studies aimed to evaluate the influence of rearing and processing conditions on that microbiota.


Assuntos
Microbiologia de Alimentos , Insetos/microbiologia , Microbiota , Animais , Contagem de Colônia Microbiana , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Indústria de Processamento de Alimentos , Gafanhotos/microbiologia , Gryllidae/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactobacillaceae/classificação , Lactobacillaceae/genética , Lactobacillaceae/isolamento & purificação , Larva/microbiologia , Listeria monocytogenes/genética , Listeria monocytogenes/isolamento & purificação , Microbiota/genética , Salmonella/genética , Salmonella/isolamento & purificação , Tenebrio/microbiologia , Leveduras/classificação , Leveduras/genética , Leveduras/isolamento & purificação
8.
Food Microbiol ; 62: 77-81, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27889169

RESUMO

A collection of 120 bacterial isolates from small medium enterprises involved in the production of cow milk and the manufacture of goat cheese were screened for sensitivity to biocides benzalkonium chloride (BC), cetrimide (CT), hexadecylpyridinium chloride (HDP), triclosan (TC), hexachlorophene (CF) and poly-(hexamethylen guanidinium) hydrochloride (PHMG). Nineteen isolates were selected according to biocide tolerance and identified by 16S rDNA sequencing as Lactococcus sp. (6) Enterococcus sp. (1), Lactobacillus sp. (4), Bacillus sp. (1) Escherichia sp. (5), Enterobacter sp. (1) and Helicobacter sp. (1). These were further characterised regarding antimicrobial resistance phenotype and genotype. Several isolates were multiply (3 or more) tolerant to biocides or resistant to antibiotics, but only two Escherichia sp. isolates and Enterobacter sp. were multiply resistant to biocides and antibiotics. Statistical analysis of biocide tolerance and antibiotic resistance revealed significant positive correlations between different biocides and between biocides and antibiotics. The biocide tolerance genes most frequently found were qacEΔ1 and qacA/B. The sulfonamide resistance gene sul1 was found in two Escherichia sp. isolates and in Enterobacter sp., all of which also carried qacEΔ1. Beta-lactam (blaCTX-M, blaPSE) and tetracycline resistance genes [tet(A), tet(C) and tet(D)] were detected. Efflux pump genes acrB and mdfA were found in most Gram-negative isolates. Results from the study suggest that exposure to biocides can indirectly select for antibiotic resistance.


Assuntos
Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Queijo/microbiologia , Indústria de Laticínios , Desinfetantes/farmacologia , Microbiologia de Alimentos , Leite/microbiologia , Animais , Antibacterianos/farmacologia , Antiporters/genética , Bactérias/genética , Proteínas de Bactérias/genética , Compostos de Benzalcônio/farmacologia , Bovinos , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/classificação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Proteínas de Escherichia coli/efeitos dos fármacos , Proteínas de Escherichia coli/genética , Feminino , Lactobacillaceae/classificação , Lactobacillaceae/efeitos dos fármacos , Lactobacillaceae/genética , Lactobacillaceae/isolamento & purificação , Testes de Sensibilidade Microbiana , Análise de Sequência de DNA , Triclosan/farmacologia
9.
J Sci Food Agric ; 97(2): 659-668, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27144959

RESUMO

BACKGROUND: Knowledge regarding microaerophilic and anaerobic specific spoilage organisms (SSOs) is crucial for an appropriate evaluation of vacuum-packed ham. The objective of this study was to characterize the SSO community in vacuum-packed ham by a culture-dependent technique and MiSeq next-generation sequencing (NGS) platform. The relation between changes among the SSO group in the ham and changes in sensory characteristics of the product was also assessed. RESULTS: In the study, conventional microbiological analyses were employed in order to establish the participation of several groups of microorganisms in the deterioration of vacuum-packed ham. The diversity of the SSO group in the product was further assessed with the use of MiSeq NGS technology. The bacteria identified in sliced cooked ham belonged mostly to four phyla, namely Actinobacteria, Proteobacteria, Firmicutes and Bacteroidetes. A temperature of 4 °C favoured the development of mesophilic and psychrophilic/psychrotrophic flora, mainly Lactobacillaceae, Enterobacteriaceae and Micrococcaceae families. A high ratio of Brochothrix thermosphacta species and new, cold-tolerant Clostridium spp. was also observed. The growth of these microorganisms facilitated changes in the pH value and organoleptic characteristics of the product. CONCLUSION: This study confirms that the combination of culturing and MiSeq NGS technology improves the microbial evaluation of food. © 2016 Society of Chemical Industry.


Assuntos
Enterobacteriaceae/crescimento & desenvolvimento , Embalagem de Alimentos , Conservação de Alimentos , Armazenamento de Alimentos , Lactobacillaceae/crescimento & desenvolvimento , Carne/microbiologia , Micrococcaceae/crescimento & desenvolvimento , Animais , Biologia Computacional , Enterobacteriaceae/classificação , Enterobacteriaceae/isolamento & purificação , Fast Foods/análise , Fast Foods/microbiologia , Qualidade dos Alimentos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Concentração de Íons de Hidrogênio , Lactobacillaceae/classificação , Lactobacillaceae/isolamento & purificação , Carne/análise , Fenômenos Mecânicos , Micrococcaceae/classificação , Micrococcaceae/isolamento & purificação , Tipagem Molecular , Polônia , Análise de Componente Principal , Refrigeração , Sensação , Sus scrofa , Vácuo
10.
Microb Ecol ; 73(1): 224-235, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27568186

RESUMO

Birds and other animals live and evolve in close contact with millions of microorganisms (microbiota). While the avian microbiota has been well characterized in domestic poultry, the microbiota of other bird species has been less investigated. The aim of this study was to describe the fecal bacterial communities of pet birds. Pooled fecal samples from 22 flocks representing over 150 individual birds of three different species (Melopsittacus undulatus or budgerigars, Nymphicus hollandicus or cockatiels, and Serinus canaria or domestic canaries) were used for analysis using the 16S rRNA gene sequencing in the MiSeq platform (Illumina). Firmicutes was the most abundant phylum (median 88.4 %; range 12.9-98.4 %) followed by other low-abundant phyla such as Proteobacteria (median 2.3 %; 0.1-85.3 %) and Actinobacteria (median 1.7 %; 0-18.3 %). Lactobacillaceae (mostly Lactobacillus spp.) was the most abundant family (median 78.1 %; 1.4-97.5 %), especially in budgerigars and canaries, and it deserves attention because of the ascribed beneficial properties of lactic acid bacteria. Importantly, feces from birds contain intestinal, urinary, and reproductive-associated microbiota thus posing a serious problem to study one anatomical region at a time. Other groups of interest include the family Clostridiaceae that showed very low abundance (overall median <0.1 %) with the exception of two samples from cockatiels (14 and 45.9 %) and one sample from budgerigars (19.9 %). Analysis of UniFrac metrics showed that overall, the microbial communities from the 22 flocks tended to cluster together for each bird species, meaning each species shed distinctive bacterial communities in feces. This descriptive analysis provides insight into the fecal microbiota of pet birds.


Assuntos
Actinobacteria/isolamento & purificação , Aves/microbiologia , Firmicutes/isolamento & purificação , Lactobacillaceae/isolamento & purificação , Animais de Estimação/microbiologia , Proteobactérias/isolamento & purificação , Actinobacteria/classificação , Actinobacteria/genética , Animais , Fezes/microbiologia , Firmicutes/classificação , Firmicutes/genética , Lactobacillaceae/classificação , Lactobacillaceae/genética , Microbiota , Proteobactérias/classificação , Proteobactérias/genética , RNA Ribossômico 16S/genética
11.
J Microbiol Biotechnol ; 27(2): 226-233, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-27780959

RESUMO

Jeung-pyun, a fermented rice cake, is prepared by fermenting rice sourdough using makgeolli, a traditional Korean rice wine, in the presence of yeast and lactic acid bacteria (LAB). The goal of this study was to conduct biochemical and microbial analyses of five different rice sourdoughs, each fermented with a different commercial makgeolli, using culture-dependent and culture-independent approaches. All sourdough samples fermented with different makgeolli for 6.5 h showed different profiles in pH, total titratable acidity, organic acid concentration, and microbial growth. LAB belonging to different genera were identified based on colony morphology on modified MRS and sourdough bacteria agar medium. PCR-denaturinggradient gel electrophoresis analyses of the five sourdoughs showed different bands corresponding to LAB and yeast. 16S/26S rRNA gene sequence analyses of the samples confirmed that the predominant LAB in the five fermented rice doughs was Lactobacillus plantarum, Lb. pentosus, and Lb. brevis. Various other Lactobacillus spp. and Saccharomyces cerevisiae were common in all five fermented samples. This study provides comprehensive and comparative information on the microflora involved in fermentation of rice sourdough and signifies the need to develop effective starters to enrich the quality of jeung-pyun.


Assuntos
Bactérias/isolamento & purificação , Farinha/microbiologia , Microbiologia de Alimentos , Lactobacillaceae/isolamento & purificação , Oryza/microbiologia , Saccharomyces cerevisiae/isolamento & purificação , Vinho , Bactérias/classificação , Bactérias/genética , Reatores Biológicos , Contagem de Colônia Microbiana , Meios de Cultura/química , DNA Bacteriano , Fermentação , Farinha/análise , Lactobacillaceae/classificação , Lactobacillaceae/genética , Lactobacillaceae/crescimento & desenvolvimento , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Lactobacillus plantarum/genética , Lactobacillus plantarum/isolamento & purificação , Reação em Cadeia da Polimerase , RNA Ribossômico 16S , Técnica de Amplificação ao Acaso de DNA Polimórfico , Saccharomyces cerevisiae/genética , Análise de Sequência de DNA
12.
Bull Exp Biol Med ; 161(6): 801-803, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27783299

RESUMO

Strain parameters of Salmonellas and Lactobacteria affecting their antagonistic activity were studied using an original method. Real-time PCR was applied for measuring the decrease in the concentration of field isolates of Salmonellas isolated from chickens in the presence of field isolates of Lactobacteria also isolated from the gastrointestinal tract of chickens and broiler chickens. Dispersion analysis showed that the probability of suppression of Salmonella growth by Lactobacteria is determined by strain parameters of both Lactobacteria and Salmonellas (p<0.001). However, strain parameters of Lactobacteria were found to be more important that Salmonella strain parameters during co-culturing.


Assuntos
Antibiose , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Lactobacillaceae/crescimento & desenvolvimento , Salmonella enterica/crescimento & desenvolvimento , Animais , Galinhas , Técnicas de Cocultura , Meios de Cultura/química , Lactobacillaceae/classificação , Lactobacillaceae/genética , Lactobacillaceae/isolamento & purificação , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Salmonella enterica/classificação , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação
13.
J Dairy Res ; 83(3): 383-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27600975

RESUMO

During the last years the interest in donkey milk has increased significantly mainly because of its compelling functional elements. Even if the composition and nutritional properties of donkey milk are known, its microbiota is less studied. This Research Communication aimed to provide a comprehensive characterisation of the lactic acid bacteria in raw donkey milk. RAPD-PCR assay combined with 16S rDNA sequencing analysis were used to describe the microbial diversity of several donkey farms in the North West part of Italy. The more frequently detected species were: Lactobacillus paracasei, Lactococcus lactis and Carnobacterium maltaromaticum. Less abundant genera were Leuconostoc, Enterococcus and Streptococcus. The yeast Kluyveromyces marxianus was also isolated. The bacterial and biotype distribution notably diverged among the farms. Several of the found species, not previously detected in donkey milk, could have an important probiotic activity and biotechnological potential. This study represents an important insight to the ample diversity of the microorganisms present in the highly selective ecosystem of raw donkey milk.


Assuntos
Equidae/microbiologia , Lactobacillaceae/classificação , Lactobacillaceae/isolamento & purificação , Leite/microbiologia , Animais , Biodiversidade , Carnobacterium/genética , Carnobacterium/isolamento & purificação , DNA Bacteriano/análise , Ecossistema , Itália , Kluyveromyces/isolamento & purificação , Lactobacillaceae/genética , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Lactococcus lactis/genética , Lactococcus lactis/isolamento & purificação , Probióticos , RNA Ribossômico 16S/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico/veterinária
14.
Food Microbiol ; 60: 29-38, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27554143

RESUMO

This study aimed to select autochthonous lactic acid bacteria (LAB) with probiotic and functional properties from goat dairies and test their addition to artisanal cheese for the inhibition of Salmonella typhi. In vitro tests, including survival in the gastrointestinal tract (GIT), auto- and co-aggregation, the hemolytic test, DNase activity, antimicrobial susceptibility, antibacterial activity, tolerance to NaCl and exopolysaccharide (EPS), gas and diacetyl production were conducted for sixty isolates. Based on these tests, four LAB isolates (UNIVASF CAP 16, 45, 84 and 279) were selected and identified. Additional tests, such as production of lactic and citric acids by UNIVASF CAP isolates were performed in addition to assays of bile salt hydrolase (BSH), ß-galactosidase and decarboxylase activity. The four selected LAB produced high lactic acid (>17 g/L) and low citric acid (0.2 g/L) concentrations. All selected strains showed BSH and ß-galactosidase activity and none showed decarboxylase activity. Three goat cheeses (1, 2 and control) were produced and evaluated for the inhibitory action of selected LAB against Salmonella typhi. The cheese inoculated with LAB (cheese 2) decreased 0.38 log10 CFU/g of S. Typhy population while in the cheese without LAB inoculation (cheese 1) the pathogen population increased by 0.29 log units. Further, the pH value increased linearly over time, by 0.004 units per day in cheese 1. In the cheese 2, the pH value decreased linearly over time, by 0.066 units per day. The cocktail containing selected Lactobacillus strains with potential probiotic and technological properties showed antibacterial activity against S. typhi in vitro and in artisanal goat cheese. Thus, goat milk is important source of potential probiotic LAB which may be used to inhibit the growth of Salmonella population in cheese goat, contributing to safety and functional value of the product.


Assuntos
Antibiose , Queijo/microbiologia , Lactobacillus brevis/fisiologia , Lactobacillus paracasei/fisiologia , Leite/microbiologia , Salmonella typhi/fisiologia , Amidoidrolases/biossíntese , Animais , Ácido Cítrico/metabolismo , Indústria de Laticínios , Microbiologia de Alimentos , Inocuidade dos Alimentos , Cabras , Concentração de Íons de Hidrogênio , Ácido Láctico/biossíntese , Lactobacillaceae/classificação , Lactobacillaceae/efeitos dos fármacos , Lactobacillaceae/isolamento & purificação , Lactobacillaceae/fisiologia , Lactobacillus brevis/isolamento & purificação , Lactobacillus paracasei/isolamento & purificação , Probióticos/isolamento & purificação , Probióticos/metabolismo , beta-Galactosidase/biossíntese
15.
Appl Microbiol Biotechnol ; 100(10): 4297-308, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27037694

RESUMO

It is common knowledge that microorganisms have capabilities, like the production of antimicrobial compounds, which do not normally appear in ideal laboratory conditions. Common antimicrobial discovery techniques require the isolation of monocultures and their individual screening against target microorganisms. One strategy to achieve expression of otherwise hidden antimicrobials is induction by co-cultures. In the area of bacteriocin-producing lactic acid bacteria, there has been some research focusing into the characteristics of co-culture-inducible bacteriocin production and particularly the molecular mechanism(s) of such interactions. No clear relationship has been seen between bacteriocin-inducing and bacteriocin-producing microorganisms. The three-component regulatory system seems to be playing a central role in the induction, but inducing compounds have not been identified or characterized. However, the presence of the universal messenger molecule autoinducer-2 has been associated in some cases with the co-culture-inducible bacteriocin phenotype and it may play the role in the additional regulation of the three-component regulatory system. Understanding the mechanisms of induction would facilitate the development of strategies for screening and development of co-culture bacteriocin-producing systems and novel products as well as the perseverance of such systems in food and down to the intestinal tract, possibly conferring a probiotic effect on the host.


Assuntos
Bacteriocinas/biossíntese , Microbiologia Industrial , Lactobacillaceae/metabolismo , Anti-Infecciosos/metabolismo , Técnicas de Cocultura , Lactobacillaceae/classificação , Interações Microbianas
16.
Eur J Gastroenterol Hepatol ; 28(5): 532-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27015015

RESUMO

OBJECTIVE: An adequate bowel preparation is essential for a successful colonoscopy, but to date, only scarce information exists on the impact of the bowel cleansing on the gut microbiota, in particular, 1 month after the procedure. PATIENTS AND METHODS: Through 16S rDNA Ion Torrent profiling of fecal samples of 10 patients, we evaluated changes that occurred in the gut microbiota composition immediately after a 4 liter polyethylene glycol-based (SELG Esse) bowel lavage and 1 month thereafter. We studied the gut microbiota at the phylum, class, and family level. RESULTS: At the phyla level, we found a significant decrease in Firmicutes abundance and an increase in Proteobacteria abundance immediately after the colon cleansing and 1 month after the colonoscopy, whereas, at the class level, a significant increase in γ-Proteobacteria immediately after the colonoscopy was observed. Interestingly, 1 month after the endoscopic examination, this bacterial class was decreased 2.5-fold compared with samples before colonoscopy, as well as α-Proteobacteria. At the family level, a significant reduction in Lactobacillaceae and an increase in Enterobacteriaceae abundance were observed immediately after the colonoscopy, whereas 1 month after the bowel cleansing, these families were significantly lower compared with samples collected before the colonoscopy. Moreover, the abundance of Rikenellaceae and Eubacteriaceae has been observed to be significantly higher compared with samples collected before the bowel lavage. Finally, Streptococcaceae were increased 4.0-fold 1 month after the bowel lavage compared with fecal samples collected before the colonoscopy. CONCLUSION: We provide clear evidence that, in normal individuals, a high-volume polyethylene glycol bowel cleansing preparation has a long-lasting effect on the gut microbiota composition and homeostasis, in particular, with a decrease in the Lactobacillaceae abundance, a population of protective bacteria. Further studies are required to assess whether these changes have any metabolic, immunological, or clinical consequence.


Assuntos
Bactérias/classificação , Catárticos/efeitos adversos , Colonoscopia/efeitos adversos , Microbioma Gastrointestinal , Intestinos/microbiologia , Polietilenoglicóis/efeitos adversos , Irrigação Terapêutica/efeitos adversos , Adulto , Idoso , Bactérias/genética , Catárticos/administração & dosagem , DNA Bacteriano/genética , Fezes/microbiologia , Feminino , Homeostase , Humanos , Lactobacillaceae/classificação , Lactobacillaceae/genética , Masculino , Pessoa de Meia-Idade , Filogenia , Polietilenoglicóis/administração & dosagem , RNA Ribossômico 16S/genética , Ribotipagem , Fatores de Tempo
17.
J Appl Microbiol ; 120(5): 1289-301, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26909667

RESUMO

AIMS: To analyse lactic acid bacteria (LAB) diversity and technological-functional and safety properties of strains present during spontaneous fermented quinoa sourdoughs. METHODS AND RESULTS: Fermentation was performed by daily backslopping at 30°C for 10 days. Autochthonous LAB microbiota was monitored by a biphasic approach combining random amplified polymorphic DNA (RAPD)-PCR and rRNA gene sequencing with PCR-denaturing gradient gel electrophoresis (DGGE) analysis. Identification and intraspecies differentiation allowed to group isolates within nine LAB species belonging to four genera. A succession of LAB species occurred during 10-days backslopping; Lactobacillus plantarum and Lactobacillus brevis were detected as dominant species in the consortium. The characterization of 15 representative LAB strains was performed based on the acidifying capacity, starch and protein hydrolysis, γ-aminobutyric acid and exopolysaccharides production, antimicrobial activity and antibiotic resistance. CONCLUSION: Strains characterization led to the selection of Lact. plantarum CRL1905 and Leuconostoc mesenteroides CRL1907 as candidates to be assayed as functional starter culture for the gluten-free (GF) quinoa fermented products. SIGNIFICANCE AND IMPACT OF THE STUDY: Results on native LAB microbiota present during quinoa sourdough fermentation will allow the selection of strains with appropriate technological properties to be used as a novel functional starter culture for GF-fermented products.


Assuntos
Biodiversidade , Chenopodium quinoa/microbiologia , Lactobacillaceae/classificação , Pão/microbiologia , Fermentação , Microbiologia de Alimentos , Ácido Láctico/metabolismo , Lactobacillaceae/isolamento & purificação , Lactobacillaceae/metabolismo , Técnica de Amplificação ao Acaso de DNA Polimórfico , Ácido gama-Aminobutírico/metabolismo
18.
J Appl Microbiol ; 120(2): 266-79, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26496890

RESUMO

AIMS: This study aimed to evaluate the effects of inoculation of strains of lactic acid bacteria (LAB) isolated from sugarcane grown in a Brazil on the quality of corn silage. METHODS AND RESULTS: Three strains of Lactobacillus buchneri (UFLA SLM11, UFLA SLM103 and UFLA SLM108), five strains of Lactobacillus plantarum (UFLA SLM08, UFLA SLM41, UFLA SLM45, UFLA SLM46 and UFLA SLM105), and one strain of Leuconostoc mesenteroides (UFLA SLM06) were evaluated at 0, 10, 30, 60 and 90 day after inoculating corn forage. The inoculation of the LAB strains did not influence the chemical composition of the silage, but pH, acetic acid and 1,2-propanediol were affected by treatment. The silages inoculated with UFLA SLM11 and SLM108 contained the lowest yeast and filamentous fungi counts during fermentation. Bacteria belonging to the Enterobacteriaceae family, Clostridium genus were detected in the silages inoculated with Lact. buchneri UFLA SLM 11, 103 and 108, as shown by DGGE analysis. Silages inoculated with Lact. buchneri UFLA SLM 11 showed higher aerobic stability. CONCLUSIONS: The Lact. buchneri UFLA SLM11 strain was considered promising as a starter culture or inoculant for corn silages. SIGNIFICANCE AND IMPACT OF THE STUDY: The selection of microbial inoculants for each crop promotes improvement of silage quality. Studies on the chemical and microbiological characteristics of silage provide useful information for improving ensiling techniques.


Assuntos
Lactobacillaceae/metabolismo , Silagem/microbiologia , Zea mays/microbiologia , Aerobiose , Biodiversidade , Brasil , Fermentação , Ácido Láctico/análise , Ácido Láctico/metabolismo , Lactobacillaceae/classificação , Lactobacillaceae/genética , Lactobacillaceae/isolamento & purificação , Saccharum/microbiologia , Silagem/análise , Zea mays/química
19.
Mikrobiol Z ; 78(5): 53-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30141865

RESUMO

Homemade fermented food is a valuable source of biologically active prebiotic substances and probiotic microorganisms. Five prioritized ethnic fermented foods from the Black Sea region: Bosa (Bulgaria), Socata (Romania), Kvass (Russia), fermented beans (Turkey) and Sauerkraut (Ukraine), based on the original recipes using unique microbial starters were studied. The dynamics of microbial compositions during the fermentation process of each product was clarifed and the best combination of lactobacilli starters needed to reproduce the original formulations were defned. In addition to our earlier published data these results demonstrate the opportunity to design novel food products which might be used in the practical implementation of personalized diets.


Assuntos
Alimentos e Bebidas Fermentados/microbiologia , Microbiologia de Alimentos , Lactobacillaceae/classificação , Mar Negro , Bulgária , Probióticos , Romênia , Federação Russa , Turquia , Ucrânia
20.
Mikrobiologiia ; 85(4): 472-480, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28853779

RESUMO

Molecular genetic techniques (NGS sequencing and quantitative PCR) were used to determine the composition of the cecal bacterial community of broiler chickens fed with different mixed fodder. The Cecal microbiome exhibited taxonomic diversity, with both typical inhabitants of avian intestine belonging to the families Clostridiaceae, Eubacteriaceae, and Lactobacillaceae and to the phylum Bacteroidetes, and new un- identified taxa, as well as bacteria of the families Lachnospiraceae and Ruminococcaceae, which were previ- ously considered restricted to the rumen microflora. Contrary to traditional concepts, enterococci and bi- fidobacteria were among the minor components of the community, lactate-fermenting species were absent, and typical avian pathogens of the genus Staphylococcus were detected but seldom. Members of the family Suterellaceae and the genus Gallibacterium, which are responsible for avian respiratory infections, were also detected. Significant fluctuations of abundance and composition of microbial groups within the cecal com- munity and of the parameters of broiler productivity were found to occur depending on the feed allowance. Cellulose content in the feed had the most pronounced effect on the composition aid structure of bacterial communities. Decreased cellulose content resulted in a decrease of bacterial abundance by-aii order of mag- nitude and in increased ratios of members of the phylum Bacteroidetes and the family Clostridiaceae, which possess the enzymes degrading starch polysadcharides. Abundance of the normal inhabitants of avian intes- tine belonging to the genus Ldctobacillus and the order Bacillales decreased, while the share of Escherichia and members of the family Sutterellaceae increased, including some species capable of causing dysbiotic changes in avian intestine. No significant change in abundance of cellulolytics of the families Ruminococca- ceae, Lachnospiraceae, and Eubacteriaceae was observed.


Assuntos
Ração Animal/análise , Ceco/microbiologia , Microbioma Gastrointestinal/genética , Carne/análise , Consórcios Microbianos/genética , RNA Ribossômico 16S/genética , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Bacteroidetes/metabolismo , Bifidobacterium/classificação , Bifidobacterium/genética , Bifidobacterium/isolamento & purificação , Bifidobacterium/metabolismo , Burkholderiaceae/classificação , Burkholderiaceae/genética , Burkholderiaceae/isolamento & purificação , Burkholderiaceae/metabolismo , Celulose/metabolismo , Galinhas , Clostridiales/classificação , Clostridiales/genética , Clostridiales/isolamento & purificação , Clostridiales/metabolismo , Enterococcus/classificação , Enterococcus/genética , Enterococcus/isolamento & purificação , Enterococcus/metabolismo , Fermentação , Sequenciamento de Nucleotídeos em Larga Escala , Lactobacillaceae/classificação , Lactobacillaceae/genética , Lactobacillaceae/isolamento & purificação , Lactobacillaceae/metabolismo , Pasteurellaceae/classificação , Pasteurellaceae/genética , Pasteurellaceae/isolamento & purificação , Pasteurellaceae/metabolismo , Reação em Cadeia da Polimerase , Rúmen/microbiologia , Staphylococcus/classificação , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Staphylococcus/metabolismo , Ganho de Peso/fisiologia
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