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1.
J Sci Food Agric ; 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34628644

RESUMO

BACKGROUND: Fructooligosaccharides (FOS) have been identified as important prebiotics. Previous studies have found that they can significantly promote the proliferation of Bifidobacterium pseudolongum in the mouse intestine. However, it is still unclear which other bacteria in the mouse intestine can utilize FOS, and the differences in the ability to utilize FOS. In this study, the bacteria capable of utilizing FOS were isolated from mice feces and their ability to utilize FOS was compared. Draft genome sequencing was also applied to explain the differences in FOS utilization at the gene levels. RESULTS: A total of 15 species were isolated from mouse feces and 13 species were able to utilize fructofuranosylnystose (GF2). Eleven species could utilize nistose (GF3), but not Enterococcus hirae and Lactobacillus reuteri. In contrast, 1-kestose (GF4) was hardly utilized. The enzyme activity determination and draft genome sequencing-based analyses revealed that all isolated species used the phosphotransferase system or permease system to transport FOS into the cells before hydrolysis by ß-fructofuranosidase. Although ß-fructofuranosidase exists in all strains, there are big differences in the corresponding coding genes between bifidobacteria and non-bifidobacteria. CONCLUSION: Compared with the other isolates, Bifidobacterium species exhibited higher enzyme activity and shorter generation time, leading to a stronger ability to utilize FOS. © 2021 Society of Chemical Industry.

2.
J Appl Microbiol ; 2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34365708

RESUMO

The review deals with lactic acid bacteria in characterizing the stress adaptation with cross-protection effects, mainly associated with Lactobacillus, Bifidobacterium and Lactococcus. It focuses on adaptation and cross-protection in Lactobacillus, Bifidobacterium and Lactococcus, including heat shocking, cold stress, acid stress, osmotic stress, starvation effect, etc. Web of Science, Google Scholar, Science Direct, and PubMed databases were used for the systematic search of literature up to the year 2020. The literature suggests that a lower survival rate during freeze-drying is linked to environmental stress. Protective pretreatment under various mild stresses can be applied to lactic acid bacteria which may enhance resistance in a strain-dependent manner. We investigate the mechanism of damage and adaptation under various stresses including heat, cold, acidic, osmotic, starvation, oxidative and bile stress. Adaptive mechanisms include synthesis of stress-induced proteins, adjusting the composition of cell membrane fatty acids, accumulating compatible substances, etc. Next, we reveal the cross-protective effect of specific stress on the other environmental stresses. Freeze-drying is discussed from three perspectives including the regulation of membrane, accumulation of compatible solutes and the production of chaperones and stress-responsive proteases. The resistance of lactic acid bacteria against technological stress can be enhanced via cross-protection, which improves industrial efficiency concerning the survival of probiotics. However, the adaptive responses and cross-protection are strain-dependent and should be optimized case by case.

3.
J Agric Food Chem ; 69(27): 7619-7628, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34156842

RESUMO

This research assessed the anti-inflammatory and hepatoprotective properties of inosine and the associated mechanism. Inosine pretreatment significantly reduced the secretion of several inflammatory factors and serum alanine transaminase (ALT) and aspartate amino transferase (AST) levels in a dose-dependent manner compared with the lipopolysaccharide (LPS) group. In LPS-treated mice, inosine pretreatment significantly reduced the ALT and malondialdehyde (MDA) concentration and significantly elevated the antioxidant enzyme activity. Furthermore, inosine pretreatment significantly altered the relative abundance of the genera, Bifidobacterium, Lachnospiraceae UCG-006, and Muribaculum. Correlation analysis showed that Bifidobacterium and Lachnospiraceae UCG-006 were positively related to the cecal short-chain fatty acids but negatively related to the serum IL-6 and hepatic AST and ALT levels. Notably, inosine pretreatment significantly modulated the hepatic TLR4, MYD88, NF-κB, iNOS, COX2, AMPK, Nfr2, and IκB-α expression. These results suggested that inosine pretreatment alters the intestinal microbiota structure and improves LPS-induced acute liver damage and inflammation through modulating the TLR4/NF-κB signaling pathway.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Microbiota , Animais , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/genética , Inflamação/tratamento farmacológico , Inosina , Lipopolissacarídeos/efeitos adversos , Fígado , Camundongos , NF-kappa B/genética , Receptor 4 Toll-Like/genética
4.
Microorganisms ; 9(5)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922843

RESUMO

In recent years, Blautia has attracted attention for its role in ameliorating host diseases. In particular, Blautia producta DSM 2950 has been considered a potential probiotic due to its ability to mitigate inflammation in poly(I:C) induced HT-29 cells. Thus, to promote the development of indigenous intestinal microorganisms with potential probiotic function, we conducted a comprehensive experimental analysis of DSM 2950 to determine its safety. This comprised a study of its potential virulence genes, antibiotic resistance genes, genomic islands, antibiotic resistance, and hemolytic activity and a 14-day test of its acute oral toxicity in mice. The results indicated no toxin-related virulence genes in the DSM 2950 genome. Most of the genomic islands in DSM 2950 were related to metabolism, rather than virulence expression. DSM 2950 was sensitive to most of the tested antibiotics but was tolerant of treatment with kanamycin, neomycin, clindamycin, or ciprofloxacin, probably because it possessed the corresponding antibiotic resistance genes. Oral acute toxicity tests indicated that the consumption of DSM 2950 does not cause toxic side effects in mice. Overall, the safety profile of DSM 2950 confirmed that it could be a candidate probiotic for use in food and pharmaceutical preparations.

5.
J Sci Food Agric ; 101(13): 5721-5729, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33650140

RESUMO

BACKGROUND: Lactulose was one of the earliest prebiotics to be identified. To assess the potential risk of large intakes of lactulose to the intestinal microbiota, mice were fed a diet containing lactulose (0%, 5% and 15%, w/w) for 2 weeks and the changes in the fecal microbiota were evaluated by 16S rRNA high-throughput sequencing. RESULTS: Lactulose intervention decreased the α-diversity of the fecal microbiota in both low-dose and high-dose groups. The relative abundance of Actinobacteria was significantly increased, while that of Bacteroidetes was significantly decreased after lactulose intervention. At the genus level, the relative abundance of Bifidobacterium belonging to Actinobacteria was significantly increased, and that of Alistipes belonging to Bacteroidetes was decreased in both low-dose and high-dose groups. The relative abundance of Blautia was significantly increased from 0.2% to 7.9% in the high-dose group and one strain of Blautia producta was isolated from the mice feces. However, the strain could not utilize lactulose. CONCLUSION: Overall, the microbial diversity was decreased after lactulose treatment, with significant increases in the relative abundance of Bifidobacterium. We also provide a strategy to increase the relative abundance of Blautia in the intestine by lactulose feeding at high doses, although the mechanism is not revealed. This will help us understand the prebiotic effect of lactulose on the host health. © 2021 Society of Chemical Industry.


Assuntos
Bactérias/isolamento & purificação , Bifidobacterium/crescimento & desenvolvimento , Clostridiales/crescimento & desenvolvimento , Fezes/microbiologia , Microbioma Gastrointestinal , Lactulose/metabolismo , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bifidobacterium/metabolismo , Clostridiales/metabolismo , DNA Bacteriano/genética , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Prebióticos/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Genes (Basel) ; 12(2)2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567604

RESUMO

Lactiplantibacillus plantarum can adapt to a variety of niches and is widely distributed in many sources. We used comparative genomics to explore the differences in the genome and in the physiological characteristics of L. plantarum isolated from pickles, fermented sauce, and human feces. The relationships between genotypes and phenotypes were analyzed to address the effects of isolation source on the genetic variation of L. plantarum. The comparative genomic results indicate that the numbers of unique genes in the different strains were niche-dependent. L. plantarum isolated from fecal sources generally had more strain-specific genes than L. plantarum isolated from pickles. The phylogenetic tree and average nucleotide identity (ANI) results indicate that L. plantarum in pickles and fermented sauce clustered independently, whereas the fecal L. plantarum was distributed more uniformly in the phylogenetic tree. The pan-genome curve indicated that the L. plantarum exhibited high genomic diversity. Based on the analysis of the carbohydrate active enzyme and carbohydrate-use abilities, we found that L. plantarum strains isolated from different sources exhibited different expression of the Glycoside Hydrolases (GH) and Glycosyl Transferases (GT) families and that the expression patterns of carbohydrate active enzymes were consistent with the evolution relationships of the strains. L. plantarum strains exhibited niche-specific characteristicsand the results provided better understating on genetics of this species.


Assuntos
Adaptação Fisiológica/genética , Genoma Bacteriano/genética , Lactobacillaceae/genética , Fezes/microbiologia , Fermentação/genética , Humanos , Fenótipo , Filogenia
7.
Gut Microbes ; 13(1): 1-21, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33525961

RESUMO

Blautia is a genus of anaerobic bacteria with probiotic characteristics that occur widely in the feces and intestines of mammals. Based on phenotypic and phylogenetic analyses, some species in the genera Clostridium and Ruminococcus have been reclassified as Blautia, so to date, there are 20 new species with valid published names in this genus. An extensive body of research has recently focused on the probiotic effects of this genus, such as biological transformation and its ability to regulate host health and alleviate metabolic syndrome. This article reviews the origin and biological characteristics of Blautia and the factors that affect its abundance and discusses its role in host health, thus laying a theoretical foundation for the development of new functional microorganisms with probiotic properties.

8.
J Sci Food Agric ; 101(5): 1758-1766, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32892354

RESUMO

BACKGROUND: Lactobacillus plantarum is an important probiotic with a variety of physiologic functions. Studies have focused on the effects of L. plantarum on host physiology and microbiota, but studies of the fate of strains after they enter the intestine are lacking. In this study, L. plantarum ST-III was genetically engineered to express green fluorescent protein (GFP). Mice were administered ST-III-GFP, and fluorescence imaging was used to study the distribution, location and quantity of strains within 8 h after entry into the intestine. RESULTS: The results indicated that genetic modification did not affect the growth of ST-III, tolerance to simulated gastric juice and intestinal fluid or tolerance to antibiotics (with the exception of chloramphenicol). Fluorescence imaging and colony counting indicated that ST-III-GFP can be detected in the small intestine 5 min after oral gavage. After 30 min, nearly all ST-III-GFP was located in the small intestine. After 1.5 h, ST-III-GFP was detected in both the cecum and large intestine. After 4 and 8 h, ST-III-GFP was mainly concentrated in the cecum and large intestine. Compared to the initial amount ingested, the survival rate of ST-III-GFP within the intestine of mice was 10% after 8 h. In addition, a strong linear relationship was found between the fluorescence intensity and the viable count of ST-III-GFP. CONCLUSIONS: The obtained data indicate that the amount of ST-III-GFP can be estimated by measuring the fluorescence intensity of this novel strain within the intestinal tract. © 2020 Society of Chemical Industry.


Assuntos
Rastreamento de Células/métodos , Proteínas de Fluorescência Verde/química , Intestinos/microbiologia , Lactobacillus plantarum/química , Imagem Óptica/métodos , Probióticos/química , Animais , Contagem de Colônia Microbiana , Fluorescência , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Lactobacillus plantarum/genética , Lactobacillus plantarum/crescimento & desenvolvimento , Lactobacillus plantarum/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
9.
J Sci Food Agric ; 101(4): 1436-1446, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32839971

RESUMO

BACKGROUND: Starter cultures are nowadays more and more used to make inoculated pickles (IPs), but it remains unclear whether there are differences in flavors between IPs and naturally fermented pickles. In this study 16 commercial pickles (CPs) produced by spontaneous fermentation method were purchased from markets in Sichuan province and Chongqing. Ten strains of three lactic acid bacteria species - Lactobacillus plantarum, Leuconostoc mesenteroides and Pediococcus ethanolidurans - were selected as single starter cultures to produce IPs. RESULTS: Differences in flavor components between the CPs and IPs were monitored using a combination of gas chromatography-mass spectrometry and multivariate statistical methods. Higher levels of nonvolatile substances such as glucose, fructose, tagatose, sucrose, lactic acid and mannitol were detected in most IPs than in the CPs. The values of flavor characteristics such as sweetness, umami and astringency, which were correlated positively with consumers' overall preferences for pickles, were higher in the IPs than in the CPs. Volatile compounds such as geranyl acetate, dimethyl trisulfide, eucalyptol and linalool were distinguished as the main compounds that contributed to the flavor characteristics of the CPs. In addition to dimethyl trisulfide, dimethyl disulfide was also an odor contributor to the IPs. CONCLUSIONS: The CPs and IPs had different flavor characteristics, especially in the composition and content of volatile components, and the inoculation method reflected some fermentation advantages, which could reduce the bitterness and increase umami and lead to a higher score of sensory preference. This will be helpful for industrial production. © 2020 Society of Chemical Industry.


Assuntos
Cucumis sativus/química , Alimentos e Bebidas Fermentados/análise , Aromatizantes/química , Cucumis sativus/metabolismo , Cucumis sativus/microbiologia , Fermentação , Alimentos e Bebidas Fermentados/economia , Alimentos e Bebidas Fermentados/microbiologia , Aromatizantes/metabolismo , Microbiologia de Alimentos , Humanos , Lactobacillales/classificação , Lactobacillales/genética , Lactobacillales/isolamento & purificação , Lactobacillales/metabolismo , Metabolômica , Odorantes/análise , Paladar , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
10.
Nutrients ; 11(10)2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614751

RESUMO

Fructooligosaccharides (FOS) are considered prebiotics and have been proven to selectively promote the growth of Bifidobacterium in the gut. This study aimed to clarify the effects of FOS intake on the composition of luminal and mucosal microbiota in mice. Briefly, mice were fed a 0% or 25% FOS (w/w)-supplemented diet for four weeks, and the composition of luminal and mucosal microbiota, especially the Bifidobacterium, was analyzed by sequencing the V3-V4 region of 16S rRNA and groEL gene, respectively. After FOS intervention, there were significant increases in the total and wall weights of the cecum and the amount of total short-chain fatty acids (SCFAs) in the cecal contents of the mice. At the phylum level, the results showed a significant increase in the relative abundance of Actinobacteria in the contents and mucosa from the cecum to the distal colon in the FOS group. Besides Bifidobacterium, a significant increase was observed in the relative abundance of Coprococcus in all samples at the genus level, which may be partially related to the increase in butyric acid levels in the luminal contents. Furthermore, groEL sequencing revealed that Bifidobacterium pseudolongum was almost the sole bifidobacterial species in the luminal contents (>98%) and mucosa (>89%). These results indicated that FOS can selectively promote B. pseudolongum proliferation in the intestine, either in the lumen or the mucosa from the cecum to the distal colon. Further studies are required to reveal the competitive advantage of B. pseudolongum over other FOS-metabolizing bacteria and the response mechanisms of B. pseudolongum to FOS.


Assuntos
Bifidobacterium/efeitos dos fármacos , Ceco/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Oligossacarídeos/farmacologia , Ração Animal/análise , Animais , Bifidobacterium/classificação , Dieta/veterinária , Suplementos Nutricionais , Conteúdo Gastrointestinal/microbiologia , Masculino , Camundongos
11.
Food Funct ; 9(11): 5824-5831, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30357216

RESUMO

Raffinose has become a major focus of research interest and recent studies have shown that besides beneficial bifidobacteria and lactobacilli, Escherichia coli, Enterococcus faecium and Streptococcus pneumoniae can also utilize raffinose and raffinose might lead to flatulence in some hosts. Therefore, it is required to find out the raffinose-metabolizing bacteria in the gut and the bacteria responsible for the flatulence. The BLASTP search results showed that the homologous proteins of glycosidases related to raffinose utilization are widely distributed in 196 of the 528 gut bacterial strains. Fifty-nine bacterial strains belonging to nine species of five genera were isolated from human feces and were found to be capable of utilizing raffinose; of these species, Enterococcus avium and Streptococcus salivarius were reported for the first time. High-performance liquid chromatography (HPLC) analysis of the supernatants of the nine species revealed that the bacteria could utilize raffinose in different manners. Glucose and melibiose were detected in the supernatants of Enterococcus avium E5 and Streptococcus salivarius B5, respectively. However, no resulting saccharides of raffinose degradation were detected in the supernatants of other seven strains, indicating that they had different raffinose utilization types from Enterococcus avium E5 and Streptococcus salivarius B5. Gas was produced with raffinose utilization by Escherichia coli, Enterococcus faecium, Streptococcus macedonicus, Streptococcus pasteurianus and Enterococcus avium. Thus, more attention should be paid to the raffinose-utilizing bacteria besides bifidobacteria and further studies are required to reveal the mechanisms of raffinose utilization to clarify the relationship between raffinose and gut bacteria.


Assuntos
Fermentação , Microbioma Gastrointestinal , Rafinose/metabolismo , Bifidobacterium/isolamento & purificação , Bifidobacterium/metabolismo , Cromatografia Líquida de Alta Pressão , Enterococcus/isolamento & purificação , Enterococcus/metabolismo , Escherichia coli/isolamento & purificação , Escherichia coli/metabolismo , Fezes/microbiologia , Flatulência , Glicosídeo Hidrolases/metabolismo , Humanos , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismo , Streptococcus/isolamento & purificação , Streptococcus/metabolismo
12.
Nutrients ; 10(8)2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30115879

RESUMO

Fructooligosaccharides (FOS) are a well-known class of prebiotic and are considered to selectively stimulate the growth of bifidobacteria in the gut. Previous studies focused on the growth stimulation of Bifidobacterium, but they did not further investigate the bifidobacterial composition and the specific species that were stimulated. In this study, mice were fed with FOS in different doses for four weeks and the composition of fecal microbiota, in particular Bifidobacterium, was analyzed by sequencing the V3⁻V4 region and the groEL gene on the MiSeq platform, respectively. In the high-dose group, the relative abundance of Actinobacteria was significantly increased, which was mainly contributed by Bifidobacterium. At the genus level, the relative abundances of Blautia and Coprococcus were also significantly increased. Through the groEL sequencing, 14 species of Bifidobacterium were identified, among which B.pseudolongum was most abundant. After FOS treatment, B.pseudolongum became almost the sole bifidobacterial species (>95%). B.pseudolongum strains were isolated and demonstrated their ability to metabolize FOS by high performance liquid chromatography (HPLC). Therefore, we inferred that FOS significantly stimulated the growth of B.pseudolongum in mice. Further investigations are needed to reveal the mechanism of selectiveness between FOS and B.pseudolongum, which would aid our understanding of the basic principles between dietary carbohydrates and host health.


Assuntos
Bifidobacterium/classificação , Fezes/microbiologia , Oligossacarídeos/administração & dosagem , Ração Animal/análise , Animais , Bifidobacterium/efeitos dos fármacos , Peso Corporal , DNA Bacteriano/genética , Dieta/veterinária , Comportamento Alimentar , Genoma Bacteriano , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória
13.
Microbiol Res ; 200: 14-24, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28527760

RESUMO

Probiotics have been used to rebuild the antibiotic-induced dysfunction in gut microbiota, but whether the different strains of probiotics result in similar or reverse effects remains unclear. In this study, the different recovery effects of two cocktails (each contains four strains) of Lactobacillus and fructooligosaccharide against cefixime-induced change of gut microbiota were evaluated in C57BL/6J mice. The results show that the use of cefixime caused a reduction in the diversities of the microbial community and led to significantly decreasing to one preponderant Firmicutes phylum, which was difficult to restore naturally in the short term. The gut microbiota compositions of the groups treated with the probiotic cocktails were much more diverse than those of the natural recovery group. The effects of Lactobacillus cocktails against the cefixime-induced gut microbiota change may mainly be due to the beneficial SCFAs production in vivo and also be related to the good cell adhesion properties performed in vitro. Meanwhile, the restoration of the cefixime-induced gut microbiota was significantly different between two Lactobacillus groups since the Lactobacillus strains with high levels of fructooligosaccharide use and better cell adhesion properties performed considerably better than the Lactobacillus strains with high survival rates in the gastrointestinal tract. The contents of short-chain fatty acids in ceca were increased to 26.483±1.925 and 25.609±2.782µmol/g in the two probiotic cocktail groups respectively compared to 15.791±0.833µmol/g (P<0.05) in control group. Moreover, intestinal inflammation was alleviated by administration of the Lactobacillus cocktails. However, fructooligasaccharide administration showed certain effects on gut microbiota restoration (such as an increase of Akkermansia), although its effect on the entire microbiome structure is not so obvious.


Assuntos
Cefixima/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Lactobacillus/fisiologia , Consórcios Microbianos/efeitos dos fármacos , Oligossacarídeos/farmacologia , Animais , Análise Química do Sangue , Ceco/química , Ceco/microbiologia , Ceco/patologia , Cefixima/administração & dosagem , Adesão Celular/efeitos dos fármacos , Colo/microbiologia , Colo/patologia , DNA Bacteriano/genética , Modelos Animais de Doenças , Ácidos Graxos Voláteis/análise , Fezes/microbiologia , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/microbiologia , Células HT29 , Humanos , Íleo/microbiologia , Íleo/patologia , Intestinos , Lactobacillus/classificação , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismo , Masculino , Metagenômica , Camundongos , Camundongos Endogâmicos C57BL , Probióticos/farmacologia , RNA Ribossômico 16S/genética
14.
Sci Rep ; 8: 45840, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28374781

RESUMO

As a long-standing biomedical model, rats have been frequently used in studies exploring the correlations between gastrointestinal (GI) bacterial biota and diseases. In the present study, luminal and mucosal samples taken along the longitudinal axis of the rat digestive tract were subjected to 16S rRNA gene sequencing-based analysis to determine the baseline microbial composition. Results showed that the community diversity increased from the upper to lower GI segments and that the stratification of microbial communities as well as shift of microbial metabolites were driven by biogeographic location. A greater proportion of lactate-producing bacteria (such as Lactobacillus, Turicibacter and Streptococcus) were found in the stomach and small intestine, while anaerobic Lachnospiraceae and Ruminococcaceae, fermenting carbohydrates and plant aromatic compounds, constituted the bulk of the large-intestinal core microbiota where topologically distinct co-occurrence networks were constructed for the adjacent luminal and mucosal compartments. When comparing the GI microbiota from different hosts, we found that the rat microbial biogeography might represent a new reference, distinct from other murine animals. Our study provides the first comprehensive characterization of the rat GI microbiota landscape for the research community, laying the foundation for better understanding and predicting the disease-related alterations in microbial communities.


Assuntos
Bactérias/genética , Microbioma Gastrointestinal/genética , Trato Gastrointestinal/microbiologia , RNA Ribossômico 16S/genética , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Firmicutes/genética , Firmicutes/isolamento & purificação , Intestino Delgado/microbiologia , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Filogenia , Ratos , Análise de Sequência de DNA , Streptococcus
15.
J Agric Food Chem ; 64(31): 6240-7, 2016 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-27438677

RESUMO

In this study, C57BL/6J mice were fed diets supplemented with different proportions of lactulose (0%, 5%, and 15%) for 2 weeks to study its effects on the luminal and mucosal microbiota. The luminal and mucosal samples of cecum and colon were investigated. After high-lactulose treatment (15%), pH of the luminal contents decreased from 6.90-7.72 to 5.95-6.21 from the cecum to distal colon, and the amount of total short-chain fatty acids in the cecum was significantly increased. The luminal content was mostly dominated by Firmicutes, Actinobacteria, and Bacteroidetes, while the mucus was dominated by Firmicutes, Proteobacteria, and Bacteroidetes. The abundance of Actinobacteria was significantly increased in the content, and Proteobacteria was the most abundant phylum (∼50%) in the mucus after high-lactulose treatment. At the genus level, Bifidobacterium and Akkermansia were both significantly increased in the content, and Helicobacter was the most abundant in the mucus.


Assuntos
Bactérias/isolamento & purificação , Microbioma Gastrointestinal , Mucosa Intestinal/microbiologia , Lactulose/metabolismo , Camundongos Endogâmicos C57BL/microbiologia , Animais , Bactérias/classificação , Bactérias/metabolismo , Ceco/metabolismo , Ceco/microbiologia , Colo/metabolismo , Colo/microbiologia , Ácidos Graxos Voláteis/metabolismo , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Endogâmicos C57BL/metabolismo
16.
Food Funct ; 6(3): 947-54, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25653214

RESUMO

Fructooligosaccharides (FOS) are one of the most studied prebiotics, selectively stimulating the growth of health-promoting bacteria in the host. However, there is increasing evidence that commensal gut bacteria, such as Bacteroides fragilis, Clostridium butyricum, Enterobacter cloacae, and even the pathogenic Escherichia coli BEN2908, are also able to metabolize FOS in vitro, and in some cases, FOS displayed adverse effects. Therefore, it is necessary to identify FOS-metabolizing species that are present in the gut. Unlike previous studies focusing on individual strains, this study used the traditional culture method combined with an alignment search on the gut bacteria database established from the Human Microbiome Project (HMP). The alignment results showed that homologous proteins for FOS transporters and glycosidases were distributed in 237 of the 453 strains of gut bacteria. La506 msmK encoding the ATP-binding protein and Aec45 fosGH1 encoding glycoside hydrolase were most widely distributed, in 155 and 55 strains, respectively. Seven of eight strains with both transporters and glycosidases were proven to be capable of metabolizing FOS, while five strains without either transporters or glycosidases were not. Fifteen species isolated from human feces and 11 species from the alignment search were identified to be FOS-metabolizing, of which Cronobacter sakazakii, Marvinbryantia formatexigens, Ruminococcus gnavus, and Weissella paramesenteroides are reported here for the first time. Thus, alignment search combined with the culture method is an effective method for obtaining a global view of the FOS-metabolizing bacteria in the gut and will be helpful in further investigating the relationship between FOS and human gut bacteria.


Assuntos
Microbioma Gastrointestinal , Modelos Biológicos , Oligossacarídeos/metabolismo , Prebióticos , Adulto , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , China , Clostridiales/classificação , Clostridiales/crescimento & desenvolvimento , Clostridiales/isolamento & purificação , Clostridiales/metabolismo , Cronobacter sakazakii/classificação , Cronobacter sakazakii/crescimento & desenvolvimento , Cronobacter sakazakii/isolamento & purificação , Cronobacter sakazakii/metabolismo , Bases de Dados Genéticas , Fezes/microbiologia , Fermentação , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Humanos , Tipagem Molecular , Oligossacarídeos/efeitos adversos , Fases de Leitura Aberta , Prebióticos/efeitos adversos , Ruminococcus/classificação , Ruminococcus/crescimento & desenvolvimento , Ruminococcus/isolamento & purificação , Ruminococcus/metabolismo , Alinhamento de Sequência , Weissella/classificação , Weissella/crescimento & desenvolvimento , Weissella/isolamento & purificação , Weissella/metabolismo
17.
J Agric Food Chem ; 63(3): 856-63, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25598242

RESUMO

Fructo-oligosaccharides (FOS) are usually regarded as a type of prebiotic, favorably stimulating the growth of bifidobacteria and lactobacilli. However, they are not the specific substrates for these target species, and other bacteria, such as Streptococcus, Escherichia, and Clostridium, have been shown to be able to utilize FOS. Previous studies have mainly investigated only a few bacteria groups, and few reports analyzed the global effects of FOS on intestinal microbial communities. In this study the effects of FOS on gut bacteria in mice were investigated through a 16S rRNA metagenomic analysis. In the FOS-low group, the abundance of Actinobacteria significantly increased and that of Bacteroidetes decreased after FOS diet (5%) for 3 weeks. In the FOS-high group, Enterococcus was promoted and levels of Bifidobacterium and Olsenella both notably increased after FOS diet (25%) and the microbiota tended to revert to initial structure 2 weeks after FOS treatment ceased. The most striking observation was that Olsenella became a dominant genus comparable with Bifidobacterium after FOS treatment, and one strain of Olsenella, isolated from mice feces, was confirmed, for the first time, to be capable of using FOS. The results indicated that metagenomic analysis was helpful to reveal the FOS effects on the global composition of gut communities and new target for future studies.


Assuntos
Fezes/microbiologia , Metagenômica , Microbiota/efeitos dos fármacos , Oligossacarídeos/farmacologia , Prebióticos , Actinobacteria/efeitos dos fármacos , Actinobacteria/crescimento & desenvolvimento , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Bifidobacterium/efeitos dos fármacos , Bifidobacterium/crescimento & desenvolvimento , DNA Bacteriano/análise , Lactobacillus/efeitos dos fármacos , Lactobacillus/crescimento & desenvolvimento , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S/genética
18.
J Agric Food Chem ; 62(45): 10970-7, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25340538

RESUMO

Lactulose has been known as a prebiotic that can selectively stimulate the growth of beneficial bifidobacteria and lactobacilli. Recent studies have indicated that Streptococcus mutans, Clostridium perfringens, and Faecalibacterium prausnitzii are also able to utilize lactulose. However, the previous studies mainly focused on the utilization of lactulose by individual strains, and few studies were designed to identify the species that could utilize lactulose among gut microbiota. This study aimed to identify lactulose-metabolizing bacteria in the human gut, using in silico and traditional culture methods. The prediction results suggested that genes for the transporters and glycosidases of lactulose are well distributed in the genomes of 222 of 453 strains of gastrointestinal-tract bacteria. The screening assays identified 35 species with the ability to utilize lactulose, of which Cronobacter sakazakii, Enterococcus faecium, Klebsiella pneumoniae, and Pseudomonas putida were reported for the first time to be capable of utilizing lactulose. In addition, significant correlations between lactulose and galactooligosaccharide metabolism were found. Thus, more attention should be paid to bacteria besides bifidobacteria and lactobacilli to further investigate the relationship between functional oligosaccharides and gut bacteria.


Assuntos
Bactérias/metabolismo , Trato Gastrointestinal/microbiologia , Lactulose/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fezes/microbiologia , Fermentação , Humanos , Dados de Sequência Molecular , Filogenia
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