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1.
Int J Food Microbiol ; 336: 108898, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33129005

RESUMO

In spontaneous food fermentation processes, environmental microbiota affects the yield and quality of the fermentation productions. Although the importance of environmental microbiota has been highlighted, the ecological processes that how the environmental microbiota affects the fermentation microbial community are poorly understood. To study the effect of the environmental microbiota on community assembly, the sources of microbiota and the ecological processes of the fermentation were characterized in sauce-flavor Baijiu. Results showed that the process of sauce-flavor Baijiu making could be divided into three phases according to fermentation parameters. Heap fermentation (phase I) was an important period for rapid temperature rise, substrate utilization and production accumulation. The microbial community of heap fermentation was characterized by decrease of diversity and rapid succession of community structure. Virgibacillus, Kroppenstedtia, Bacillus and Oceanobacillus were predominant in the initial heap fermentation, while Lactobacillus was predominant during the later stage. Pichia was the predominant fungal genus during the whole fermentation process. Then, SourceTracker results showed that Daqu provided 95.6% of the bacterial community and 28.10% of the fungal community to heap fermentation, whereas the environments (indoor ground and tools) provided 71.9% of the fungal communities (mainly Pichia) to heap fermentation. Next, the results revealed that the temperature, ethanol and microbial interaction of Pichia synergistically drove the dynamic of the microbial community during the heap fermentation process. Pichia was proved to be the heat-resistant fungi and strong competitor based on growth in different temperature and competition assays in vitro. Finally, the quick succession of heap fermentation microbiota increased the enrichment of volatile flavors such as acids and esters. Our comprehensive methods shows that Pichia, which mainly comes from the environment, can construct the microbial community of Baijiu fermentation, and highlights the importance of environmental microbiota in attempts to control and promote the formation of Baijiu fermentation microbial community. This systematic study of environmental microbiota is valuable for quality control and management during spontaneous fermentation.


Assuntos
Biodiversidade , Fermentação , Aromatizantes/microbiologia , Microbiologia de Alimentos , Interações Microbianas , Microbiota/fisiologia , Pichia/fisiologia , Bacillus/fisiologia , Bactérias/classificação , Aromatizantes/normas , Lactobacillus/fisiologia , Pichia/química
2.
Nat Commun ; 11(1): 6363, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33311466

RESUMO

Depression is the leading cause of disability worldwide. Recent observations have revealed an association between mood disorders and alterations of the intestinal microbiota. Here, using unpredictable chronic mild stress (UCMS) as a mouse model of depression, we show that UCMS mice display phenotypic alterations, which could be transferred from UCMS donors to naïve recipient mice by fecal microbiota transplantation. The cellular and behavioral alterations observed in recipient mice were accompanied by a decrease in the endocannabinoid (eCB) signaling due to lower peripheral levels of fatty acid precursors of eCB ligands. The adverse effects of UCMS-transferred microbiota were alleviated by selectively enhancing the central eCB or by complementation with a strain of the Lactobacilli genus. Our findings provide a mechanistic scenario for how chronic stress, diet and gut microbiota generate a pathological feed-forward loop that contributes to despair behavior via the central eCB system.


Assuntos
Comportamento Animal , Depressão/complicações , Endocanabinoides/farmacologia , Microbioma Gastrointestinal/fisiologia , Estresse Psicológico/complicações , Animais , Modelos Animais de Doenças , Ácidos Graxos/metabolismo , Transplante de Microbiota Fecal , Lactobacillus/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurogênese/efeitos dos fármacos
3.
PLoS One ; 15(12): e0234893, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382695

RESUMO

Breast cancer is the second leading cause of cancer-related mortality in women. Various nutritional compounds possess anti-carcinogenic properties which may be mediated through their effects on the gut microbiota and its production of short-chain fatty acids (SCFAs) for the prevention of breast cancer. We evaluated the impact of broccoli sprouts (BSp), green tea polyphenols (GTPs) and their combination on the gut microbiota and SCFAs metabolism from the microbiota in Her2/neu transgenic mice that spontaneously develop estrogen receptor-negative [ER(-)] mammary tumors. The mice were grouped based on the dietary treatment: control, BSp, GTPs or their combination from beginning in early life (BE) or life-long from conception (LC). We found that the combination group showed the strongest inhibiting effect on tumor growth volume and a significant increase in tumor latency. BSp treatment was integrally more efficacious than the GTPs group when compared to the control group. There was similar clustering of microbiota of BSp-fed mice with combination-fed mice, and GTPs-fed mice with control-fed mice at pre-tumor in the BE group and at pre-tumor and post-tumor in the LC group. The mice on all dietary treatment groups incurred a significant increase of Adlercreutzia, Lactobacillus genus and Lachnospiraceae, S24-7 family in the both BE and LC groups. We found no change in SCFAs levels in the plasma of BSp-fed, GTPs-fed and combination-fed mice of the BE group. Marked changes were observed in the mice of the LC group consisting of significant increases in propionate and isobutyrate in GTPs-fed and combination-fed mice. These studies indicate that nutrients such as BSp and GTPs differentially affect the gut microbial composition in both the BE and LC groups and the key metabolites (SCFAs) levels in the LC group. The findings also suggest that temporal factors related to different time windows of consumption during the life-span can have a promising influence on the gut microbial composition, SCFAs profiles and ER(-) breast cancer prevention.


Assuntos
Dieta/métodos , Ácidos Graxos Voláteis/sangue , Microbioma Gastrointestinal/efeitos dos fármacos , Neoplasias Mamárias Experimentais/prevenção & controle , Polifenóis/farmacologia , Plântula/química , Actinobacteria/efeitos dos fármacos , Actinobacteria/isolamento & purificação , Actinobacteria/fisiologia , Animais , Brassica/química , Clostridiales/efeitos dos fármacos , Clostridiales/isolamento & purificação , Clostridiales/fisiologia , Feminino , Microbioma Gastrointestinal/fisiologia , Expressão Gênica , Lactobacillus/efeitos dos fármacos , Lactobacillus/isolamento & purificação , Lactobacillus/fisiologia , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/sangue , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Knockout , Polifenóis/química , Receptor ErbB-2/deficiência , Receptor ErbB-2/genética , Receptores Estrogênicos/deficiência , Receptores Estrogênicos/genética , Chá/química
4.
Eur Rev Med Pharmacol Sci ; 24(17): 9182-9187, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32965012

RESUMO

COVID-19 pandemic has underlined that unknown viral infections, which jump from animals to humans, can be extremely dangerous. In case of new viruses as SARS-CoV2, available drugs can fail to contrast the virus aggressiveness leading patients to death. Long time is necessary to create a vaccine, but immediate solutions are necessary to stop the mortality COVID-19 related. We have learned that the immune-system is the key to reduce the severity of COVID-19 and, through its modulation, it has been possible saving people's life. In this short communication, we discuss the use of nutraceuticals to modulate and stimulate the immune answer for reducing the severity of COVID-19 symptoms. The nutraceuticals are safe and can be administered to all ages. In addition, combination of natural anti-viral elements and immune-stimulating molecules already successfully tested against others upper-respiratory tract infections-could be efficient against SARS-CoV2. We believe that these natural molecules could really be a valid ally against COVID-19, especially in this moment in which a SARS-CoV2 vaccine is still not available.


Assuntos
Infecções por Coronavirus/terapia , Suplementos Nutricionais , Pneumonia Viral/terapia , Antivirais/química , Antivirais/farmacologia , Antivirais/uso terapêutico , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Humanos , Lactobacillus/fisiologia , Pandemias , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Selênio/farmacologia , Selênio/uso terapêutico , Índice de Gravidade de Doença , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Replicação Viral/efeitos dos fármacos
6.
J Anim Sci ; 98(9)2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32914845

RESUMO

Kefir is a fermented beverage containing yeast and bacteria produced by the fermentation of water or milk with kefir grains. Lack of regulation for probiotic-containing fermented food sold for companion dogs and cats creates the potential for misreporting on viable microbial counts, taxonomy, and label claims. In this study, the microbiota of six companion animal kefir products were measured quantitatively using standard plating techniques. Microbial composition of these products was also characterized by using high-resolution, long-read amplicon sequencing of the 16S rRNA gene. Five products (83%) listed specific microorganisms, and four products (66%) guaranteed colony forming units (CFU)/g on their label. To enumerate viable lactic acid bacteria (LAB), two lots of each homogenized product were plated upon opening and following 14 d on deMan Rogosa and Sharpe (MRS) agar and incubated under anaerobic and aerobic conditions. Results from point of opening revealed that all commercial kefir products with a guaranteed CFU/g overstated the number of microorganisms present by at least 1 log, with only one product exceeding 1 × 109 CFU/g. Sequencing results demonstrated that none of the labels claiming specific bacterial genera and species on their labels were correct, and all products contained at least three additional bacterial species above the minimum detectable threshold (0.001% relative abundance) that were not disclosed by the manufacturer. In addition to the incorrect viable CFU and bacterial taxonomies, several of the product labels and websites contained a wide range of health claims, none of which are supported by the companion animal literature. Our results demonstrate a low level of accuracy in the labeling of commercial kefir products intended for use in dogs and cats. Regulatory agencies, veterinarians, pet food professionals, and pet owners must scrutinize these products and demand a higher level of accuracy and quality in the future.


Assuntos
Gatos/fisiologia , Cães/fisiologia , Kefir/microbiologia , Lactobacillus/fisiologia , Leite/microbiologia , Probióticos , Animais , Bactérias/classificação , Bactérias/genética , Alimentos e Bebidas Fermentados/normas , Kefir/normas , Lactobacillus/genética , Animais de Estimação , Rotulagem de Produtos , Leveduras/classificação , Leveduras/genética
7.
J Med Life ; 13(2): 200-205, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32742514

RESUMO

The work assessed the state of the intestinal microbiocenosis in 52 puerperae at the in whom the pregnancy developed against the background of the metabolic syndrome. The diagnosis of metabolic syndrome was determined according to the criteria approved by the World Health Organization for pregnant women. The state of intestinal microbiocenosis was assessed by a bacteriological examination of feces immediately after delivery. The content of the main representatives of the obligate microflora (bifidobacteria, lactobacilli, native intestinal bacilli, fecal streptococci) and facultative (conditionally pathogenic) microorganisms (representatives of the genus Prоteus, Klebsiella, pathogenic strains of E. coli, Staphylococcus epidermidis, Enterobacter, Citrobacter, Clostridium difficile, Candida fungi) was determined. Cultures were made on appropriate growth media. At the time of birth, all patients of group I showed signs of intestinal microbiocenosis disorder. At the same time, 13 (54.2%) puerperae were diagnosed signs of dysbiosis of II degree, 9 (37.5%) with signs of III degree, which were generally characterized by a significant decrease in the content of the main representatives of obligate microflora (Bifidobacterium, Lactobacillus, Escherichia coli, Fecal streptococci) with simultaneous high contamination of Candida albicans and Clostridium difficile. So, it can be considered as a possible predictor of very early preterm birth in women with MS. In pregnant women with MS, but who gave timely birth (group II), dysbiotic disorders were detected to a lesser extent. Thus, in 13 (46.4%) patients, initial signs of intestinal dysbiosis (first degree) were detected in 4 (14.3%) patients (second degree). In 11 (39.3%) puerperae of group II, microbial indices indicated normal eubiotic ratios.


Assuntos
Disbiose/microbiologia , Disbiose/patologia , Intestinos/microbiologia , Intestinos/patologia , Síndrome Metabólica/complicações , Trabalho de Parto Prematuro/microbiologia , Adulto , Bifidobacterium/fisiologia , Escherichia coli/fisiologia , Fezes/microbiologia , Feminino , Humanos , Recém-Nascido , Lactobacillus/fisiologia , Gravidez , Adulto Jovem
8.
Int J Food Microbiol ; 334: 108804, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-32818764

RESUMO

Listeria monocytogenes can form long-lasting biofilms on food-contact surfaces. Lactic acid bacteria (LAB) have shown promise in antagonizing this microorganism in liquid media. However, the ecological relationships differ when cells are forming biofilms. In this work, we propose the use of Lactobacillus biofilms as surface "conditioners" to modulate the adhesion of L. monocytogenes. For this, the biofilm formation ability of Lactobacillus fermentum MP26 and Lactobacillus salivarius MP14 (human milk origin), fluorescently labeled by transfer of the mCherry-encoding pRCR12 plasmid, was first evaluated. Then, mature biofilms of these strains transformed with pRCR12 for expressing the fluorescent protein mCherry were used as adhesion substrate for GFP-tagged L. monocytogenes Scott A. The resulting biofilms were studied in terms of cellular population and attached biomass (cells plus matrix). Species distribution inside the biofilm structure was revealed by confocal laser scanning microscopy (CLSM). Although none of the Lactobacillus spp. strains reduced the adhesion of L. monocytogenes Scott A, species interactions seem to interfere with the synthesis of extracellular polymeric substances and species distribution inside the biofilms. In dual-species biofilms, CLSM images revealed that Lactobacillus cells were trapping those of L. monocytogenes Scott A. When surfaces were conditioned with Lactobacillus biofilms, the spatial distribution of L. monocytogenes Scott A cells was species-specific, suggesting these interactions are governing the ultimate biofilm structure. The results here obtained open new possibilities for controlling L. monocytogenes dispersal using these Lactobacillus spp. biofilms as a "natural" immobilization way. Whether species interactions could modify the virulence of L. monocytogenes still remains unclear.


Assuntos
Aderência Bacteriana/fisiologia , Biofilmes , Vidro/química , Lactobacillus/fisiologia , Listeria monocytogenes/fisiologia , Biofilmes/crescimento & desenvolvimento , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Humanos , Interações Microbianas
9.
Nat Commun ; 11(1): 3692, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703946

RESUMO

Following birth, the neonatal intestine is exposed to maternal and environmental bacteria that successively form a dense and highly dynamic intestinal microbiota. Whereas the effect of exogenous factors has been extensively investigated, endogenous, host-mediated mechanisms have remained largely unexplored. Concomitantly with microbial colonization, the liver undergoes functional transition from a hematopoietic organ to a central organ of metabolic regulation and immune surveillance. The aim of the present study was to analyze the influence of the developing hepatic function and liver metabolism on the early intestinal microbiota. Here, we report on the characterization of the colonization dynamics and liver metabolism in the murine gastrointestinal tract (n = 6-10 per age group) using metabolomic and microbial profiling in combination with multivariate analysis. We observed major age-dependent microbial and metabolic changes and identified bile acids as potent drivers of the early intestinal microbiota maturation. Consistently, oral administration of tauro-cholic acid or ß-tauro-murocholic acid to newborn mice (n = 7-14 per group) accelerated postnatal microbiota maturation.


Assuntos
Ácidos e Sais Biliares/metabolismo , Microbioma Gastrointestinal , Administração Oral , Animais , Animais Recém-Nascidos , Ácidos e Sais Biliares/administração & dosagem , Absorção Intestinal , Cinética , Lactobacillus/fisiologia , Fígado/metabolismo , Metabolômica , Camundongos Endogâmicos C57BL , Filogenia , Análise de Componente Principal
10.
Artigo em Inglês | MEDLINE | ID: mdl-32403297

RESUMO

A variety of activities potentially contribute to the beneficial effects of probiotic bacteria observed in humans. Among these is a direct inhibition of the growth of pathogenic bacteria in the gut. The present study characterizes head-to-head the in-vitro pathogen growth inhibition of clinically relevant infectious bacterial strains by different types of probiotics and a synbiotic. In-vitro growth inhibition of Escherichia (E.) coli EPEC, Shigella (Sh.) sonnei, Salmonella (S.) typhimurium, Klebsiella (K.) pneumoniae and Clostridioides (C.) difficile were determined. Investigated products were a yeast mono strain probiotic containing Saccharomyces (Sac.) boulardii, bacterial mono strain probiotics containing either Lactobacillus (L.) rhamnosus GG or L. reuteri DSM 17938, a multi strain probiotic containing three L. rhamnosus strains (E/N, Oxy, Pen), and a multi strain synbiotic containing nine different probiotic bacterial strains and the prebiotic fructooligosaccharides (FOS). Inhibition of pathogens was moderate by Sac. boulardii and L. rhamnosus GG, medium by L. reuteri DSM 17938 and the L. rhamnosus E/N, Oxy, Pen mixture and strong by the multi strain synbiotic. Head-to-head in-vitro pathogen growth inhibition experiments can be used to differentiate products from different categories containing probiotic microorganisms and can support the selection process of products for further clinical evaluation.


Assuntos
Clostridium/crescimento & desenvolvimento , Enterobacteriaceae/crescimento & desenvolvimento , Lactobacillus/fisiologia , Probióticos , Saccharomyces/fisiologia , Simbióticos , Antibiose , Clostridium/patogenicidade , Enterobacteriaceae/patogenicidade , Humanos , Oligossacarídeos , Prebióticos
11.
Int J Infect Dis ; 96: 524-530, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32439543

RESUMO

OBJECTIVES: To evaluate the potential probiotic properties of Lactobacillus strains isolated from feces of infants and also to determine their antimicrobial activity against some enteropathogenic bacteria. METHODS: The Fecal samples were prepared from 120 infants aged less than 24 months. In total, 105 Lactobacillus strains were identified by phenotypic tests. Thirty isolates were randomly selected to study their potential probiotic properties. These isolates were examined for resistance to acid (pH: 2.5, 2 h) and bile (oxgall 0.3%, 8 h), adhesion to HT-29 cells, antibiotic susceptibility, and antimicrobial activities. RESULTS: On basis of 16S rRNA sequencing, 30 isolates identified as Lactobacillus fermentum (n = 11; 36.7%), Lactobacillus plantarum (n = 9; 30%), Lactobacillus rhamnosus (n = 6; 20%), and Lactobacillus paracasei (n = 4; 13.3%). All tested strains survived at acid and bile conditions. Six Lactobacillus strains revealed high adherence to HT-29 cells. Three strains including the L. fermentum (N2, N7), and the L. plantarum (N20) showed good probiotic potential and inhibited the growth of Yersinia enterocolitica ATCC 23715, Shigella flexneri ATCC 12022, Salmonella enterica ATCC 9270, and enteropathogenic Escherichia coli (EPEC) ATCC 43887. The antibiotic resistance test showed that all the isolates were susceptible to tetracycline, and chloramphenicol. CONCLUSIONS: Lactobacillus strains like L. fermentum (N2, N7), and the L. plantarum (N20), could be potential probiotic, but further in vitro and in vivo studies on these probiotic strains are still required.


Assuntos
Lactobacillus/isolamento & purificação , Probióticos/química , Antibacterianos/farmacologia , Aderência Bacteriana , Pré-Escolar , Fezes/microbiologia , Feminino , Humanos , Lactente , Irã (Geográfico) , Lactobacillus/classificação , Lactobacillus/genética , Lactobacillus/fisiologia , Masculino , Probióticos/classificação , Probióticos/isolamento & purificação , Probióticos/farmacologia , RNA Ribossômico 16S/genética , Yersinia enterocolitica/efeitos dos fármacos , Yersinia enterocolitica/crescimento & desenvolvimento
12.
PLoS One ; 15(4): e0228798, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32330172

RESUMO

OBJECTIVE: This study aimed to investigate salivary levels of Streptococcus mutans (S. mutans) and Lactobacilli, and other salivary indices in subjects wearing clear aligners (CA) in comparison with multibrackets orthodontic appliances (MB). MATERIALS AND METHODS: A sample of 80 participants (46 males and 34 females) was included in the study: 40 subjects (aged 20.4±1.7 years) were treated with CA, and 40 (aged 21.3±1.7 years) were treated with MB. Plaque index (PI), salivary flow, buffering power of saliva, and salivary levels of S. mutans and Lactobacilli were evaluated prior to start of orthodontic treatment (t0), after 3 months (t1) and 6 months (t2). RESULTS: CA patients maintained PI at level 0 over time, while MB participants experienced a statistically significant increasing trend of PI over time. In addition, at t2, 37.5% of MB participants (15 subjects over 40) showed risky salivary levels (CFU/ml>105) of S. mutans (odds ratio = 7.40; 95% C.I. = 1.94-28.25; chi-square = 10.32; p = 0.001) as well as Lactobacilli (odds ratio = 23.40; 95% C.I. = 2.91-188.36; chi-square = 15.31; p = 0.0001). CONCLUSIONS: Comparing all the data, subjects treated with CA achieved lower salivary microbial colonization after 6 months of treatment compared with MB. Different additional strategies for plaque control and salivary microbial colonization must be triggered considering the type of orthodontic appliance.


Assuntos
Índice de Placa Dentária , Lactobacillus/fisiologia , Aparelhos Ortodônticos Fixos , Aparelhos Ortodônticos Removíveis , Saliva/microbiologia , Streptococcus mutans/fisiologia , Contagem de Colônia Microbiana , Feminino , Humanos , Lactobacillus/crescimento & desenvolvimento , Masculino , Streptococcus mutans/crescimento & desenvolvimento , Adulto Jovem
13.
Appl Environ Microbiol ; 86(12)2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32303552

RESUMO

Among the bacterial genera that are used for cheese production, Lactobacillus is a key taxon of high industrial relevance that is commonly present in commercial starter cultures for dairy fermentations. Certain lactobacilli play a defining role in the development of the organoleptic features during the ripening stages of particular cheeses. We performed an in-depth 16S rRNA gene-based microbiota analysis coupled with internally transcribed spacer-mediated Lactobacillus compositional profiling of 21 common Italian cheeses produced from raw milk in order to evaluate the ecological distribution of lactobacilli associated with this food matrix. Statistical analysis of the collected data revealed the existence of putative Lactobacillus community state types (LCSTs), which consist of clusters of Lactobacillus (sub)species. Each LCST is dominated by one or two taxa that appear to represent keystone elements of an elaborate network of positive and negative interactions with minor components of the cheese microbiota. The results obtained in this study reveal the existence of peculiar cheese microbiota assemblies that represent intriguing targets for further functional studies aimed at dissecting the species-specific role of bacteria in cheese manufacturing.IMPORTANCE The microbiota is known to play a key role in the development of the organoleptic features of dairy products. Lactobacilli have been reported to represent one of the main components of the nonstarter bacterial population, i.e., bacteria that are not deliberately added to the milk, harbored by cheese, although the species-level composition of this microbial population has never been assessed in detail. In the present study, we applied a recently developed metagenomic approach that employs an internally transcribed spacer to profile the Lactobacillus population harbored by cheese produced from raw milk at the (sub)species level. The obtained data revealed the existence of particular Lactobacillus community state types consisting of clusters of Lactobacillus (sub)species that tend to cooccur in the screened cheeses. Moreover, analysis of covariances between members of this genus indicate that these taxa form an elaborate network of positive and negative interactions that define specific clusters of covariant lactobacilli.


Assuntos
Queijo/microbiologia , Lactobacillus/fisiologia , Leite/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Itália , Lactobacillus/classificação , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Microbiota , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
14.
Int J Mol Sci ; 21(7)2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32276519

RESUMO

Lactic acid bacteria can act as reservoirs of antibiotic resistance genes that can be ultimately transferred to pathogens. The present work reports on the minimum inhibitory concentration (MIC) of 16 antibiotics to 25 LAB isolates of five Lactobacillus and one Bifidobacterium species from the human vagina. Acquired resistances were detected to kanamycin, streptomycin, chloramphenicol, gentamicin, and ampicillin. A PCR analysis of lactobacilli failed to identify genetic determinants involved in any of these resistances. Surprisingly, a tet(W) gene was detected by PCR in two Bifidobacterium bifidum strains, although they proved to be tetracycline-susceptible. In agreement with the PCR results, no acquired genes were identified in the genome of any of the Lactobacillus spp. strains sequenced. A genome analysis of B. bifidum VA07-1AN showed an insertion of two guanines in the middle of tet(W) interrupting the open reading frame. By growing the strain in the presence of tetracycline, stable tetracycline-resistant variants were obtained. An amino acid substitution in the ribosomal protein S12 (K43R) was further identified as the most likely cause of VA07-1AN being streptomycin resistance. The results of this work expand our knowledge of the resistance profiles of vaginal LAB and provide evidence for the genetic basis of some acquired resistances.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Lactobacillales/fisiologia , Polimorfismo Genético , Vagina/microbiologia , Bifidobacterium bifidum/efeitos dos fármacos , Bifidobacterium bifidum/genética , Bifidobacterium bifidum/fisiologia , Feminino , Humanos , Lactobacillales/efeitos dos fármacos , Lactobacillales/genética , Lactobacillus/efeitos dos fármacos , Lactobacillus/genética , Lactobacillus/fisiologia , Tetraciclina/farmacologia
15.
J Food Sci ; 85(5): 1596-1604, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32267970

RESUMO

The human gut microbiome has been classified into three distinct enterotypes (Bacteroides, Prevotella, and Ruminococcus). The relationship between probiotics and gut enterotype is not yet clear. Cayenne pepper is effective in vitro as a prebiotic for Bifidobacteria and Lactobacilli, so cayenne ingestion with probiotics may lead to more profound gut microbial shifts. We aimed to determine whether probiotics (with or without cayenne pepper) alter gut bacterial community composition and if these changes are associated with the original gut enterotype of the individual. A total of 27 adult participants provided three fecal samples: prior to probiotic treatment (baseline), post probiotic treatment (probiotic), and post probiotic plus cayenne pepper treatment (probiotic + cayenne). DNA was extracted, amplified, and the V4 region sequenced on the Illumina MiSeq platform using V2 chemistry. Sequence reads were processed in mothur and assigned using the SILVA reference by phylotype. Three enterotypes characterized the study population-Bacteroides (B; n = 6), Prevotella (P; n = 11), and Ruminoccocus (R; n = 10). There was no significant increase in probiotic genera in fecal samples after treatment periods. Alpha diversity scores were significantly lower in B-type but not in P- or R-type individuals after probiotic treatment. For the majority of individuals, their enterotype remained constant regardless of probiotic (and cayenne) treatment. This suggests that baseline gut community characteristics and enterotype classification influence responsiveness to probiotic treatment, but that enterotype is stable across administration of prebiotic and probiotics. PRACTICAL APPLICATION: A person's gut microbial community influences their responsiveness to probiotics and prebiotic ingredients. Consumers must understand that it is difficult to shift their gut microbiota even with simultaneous administration of prebiotic and probiotic. Greater understanding of these phenomena will enable consumers to choose the most efficacious products for their needs.


Assuntos
Bifidobacterium/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Lactobacillus/fisiologia , Probióticos/administração & dosagem , Adulto , Bacteroides/genética , Bacteroides/crescimento & desenvolvimento , Bacteroides/isolamento & purificação , Fezes/microbiologia , Feminino , Humanos , Masculino , Prebióticos/administração & dosagem , Prevotella/genética , Prevotella/crescimento & desenvolvimento , Prevotella/isolamento & purificação , Ruminococcus/genética , Ruminococcus/crescimento & desenvolvimento , Ruminococcus/isolamento & purificação , Adulto Jovem
16.
Pol J Microbiol ; 69(1): 5-18, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32189480

RESUMO

Probiotics are considered an alternative to antibiotics in the prevention and treatment of Salmonella diseases in poultry. However, to use probiotics as proposed above, it is necessary to evaluate their properties in detail and to select the most effective bacterial strains in the application targeted. In this study, probiotic properties of new Lactobacillus sp. strains were investigated and their antimicrobial activity against 125 environmental strains of Salmonella sp. was determined using the agar slab method. Furthermore, their survival in the presence of bile salts and at low pH, antibiotics susceptibility, aggregation and coaggregation ability, adherence to polystyrene and Caco-2 cells, and cytotoxicity were investigated. Each strain tested showed antagonistic activity against at least 96% of the environmental Salmonella sp. strains and thus representing a highly epidemiologically differentiated collection of poultry isolates. In addition, the probiotic properties of new Lactobacillus strains are promising. Therefore, all strains examined showed a high potential for use in poultry against salmonellosis.Probiotics are considered an alternative to antibiotics in the prevention and treatment of Salmonella diseases in poultry. However, to use probiotics as proposed above, it is necessary to evaluate their properties in detail and to select the most effective bacterial strains in the application targeted. In this study, probiotic properties of new Lactobacillus sp. strains were investigated and their antimicrobial activity against 125 environmental strains of Salmonella sp. was determined using the agar slab method. Furthermore, their survival in the presence of bile salts and at low pH, antibiotics susceptibility, aggregation and coaggregation ability, adherence to polystyrene and Caco-2 cells, and cytotoxicity were investigated. Each strain tested showed antagonistic activity against at least 96% of the environmental Salmonella sp. strains and thus representing a highly epidemiologically differentiated collection of poultry isolates. In addition, the probiotic properties of new Lactobacillus strains are promising. Therefore, all strains examined showed a high potential for use in poultry against salmonellosis.


Assuntos
Antibiose , Lactobacillus/fisiologia , Doenças das Aves Domésticas/prevenção & controle , Probióticos/administração & dosagem , Salmonelose Animal/prevenção & controle , Salmonella/patogenicidade , Animais , Aderência Bacteriana , Células CACO-2 , Humanos , Aves Domésticas/microbiologia , Doenças das Aves Domésticas/microbiologia
17.
PLoS Biol ; 18(3): e3000681, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32196485

RESUMO

The interplay between nutrition and the microbial communities colonizing the gastrointestinal tract (i.e., gut microbiota) determines juvenile growth trajectory. Nutritional deficiencies trigger developmental delays, and an immature gut microbiota is a hallmark of pathologies related to childhood undernutrition. However, how host-associated bacteria modulate the impact of nutrition on juvenile growth remains elusive. Here, using gnotobiotic Drosophila melanogaster larvae independently associated with Acetobacter pomorumWJL (ApWJL) and Lactobacillus plantarumNC8 (LpNC8), 2 model Drosophila-associated bacteria, we performed a large-scale, systematic nutritional screen based on larval growth in 40 different and precisely controlled nutritional environments. We combined these results with genome-based metabolic network reconstruction to define the biosynthetic capacities of Drosophila germ-free (GF) larvae and its 2 bacterial partners. We first established that ApWJL and LpNC8 differentially fulfill the nutritional requirements of the ex-GF larvae and parsed such difference down to individual amino acids, vitamins, other micronutrients, and trace metals. We found that Drosophila-associated bacteria not only fortify the host's diet with essential nutrients but, in specific instances, functionally compensate for host auxotrophies by either providing a metabolic intermediate or nutrient derivative to the host or by uptaking, concentrating, and delivering contaminant traces of micronutrients. Our systematic work reveals that beyond the molecular dialogue engaged between the host and its bacterial partners, Drosophila and its associated bacteria establish an integrated nutritional network relying on nutrient provision and utilization.


Assuntos
Acetobacter/fisiologia , Drosophila melanogaster/microbiologia , Drosophila melanogaster/fisiologia , Lactobacillus/fisiologia , Necessidades Nutricionais/fisiologia , Acetobacter/genética , Acetobacter/metabolismo , Aminoácidos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Microbioma Gastrointestinal , Interações entre Hospedeiro e Microrganismos , Lactobacillus/genética , Lactobacillus/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Larva/microbiologia , Larva/fisiologia , Redes e Vias Metabólicas , Micronutrientes/metabolismo , Especificidade da Espécie
18.
Sci Rep ; 10(1): 4183, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144319

RESUMO

In an exploratory, block-randomised, parallel, double-blind, single-centre, placebo-controlled superiority study (ISRCTN12562026, funded by Cultech Ltd), 220 Bulgarian participants (30 to 65 years old) with BMI 25-34.9 kg/m2 received Lab4P probiotic (50 billion/day) or a matched placebo for 6 months. Participants maintained their normal diet and lifestyle. Primary outcomes were changes in body weight, BMI, waist circumference (WC), waist-to-height ratio (WtHR), blood pressure and plasma lipids. Secondary outcomes were changes in plasma C-reactive protein (CRP), the diversity of the faecal microbiota, quality of life (QoL) assessments and the incidence of upper respiratory tract infection (URTI). Significant between group decreases in body weight (1.3 kg, p < 0.0001), BMI (0.045 kg/m2, p < 0.0001), WC (0.94 cm, p < 0.0001) and WtHR (0.006, p < 0.0001) were in favour of the probiotic. Stratification identified greater body weight reductions in overweight subjects (1.88%, p < 0.0001) and in females (1.62%, p = 0.0005). Greatest weight losses were among probiotic hypercholesterolaemic participants (-2.5%, p < 0.0001) alongside a significant between group reduction in small dense LDL-cholesterol (0.2 mmol/L, p = 0.0241). Improvements in QoL and the incidence rate ratio of URTI (0.60, p < 0.0001) were recorded for the probiotic group. No adverse events were recorded. Six months supplementation with Lab4P probiotic resulted in significant weight reduction and improved small dense low-density lipoprotein-cholesterol (sdLDL-C) profiles, QoL and URTI incidence outcomes in overweight/obese individuals.


Assuntos
Bifidobacterium/fisiologia , Lactobacillus/fisiologia , Obesidade/tratamento farmacológico , Obesidade/microbiologia , Sobrepeso/tratamento farmacológico , Sobrepeso/microbiologia , Probióticos/uso terapêutico , Peso Corporal/fisiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecções Respiratórias , Circunferência da Cintura/fisiologia , Perda de Peso/fisiologia
19.
Sci Rep ; 10(1): 3884, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127550

RESUMO

Bacterial vaginosis (BV) is associated with HIV acquisition and adverse pregnancy outcomes. Recurrence after metronidazole treatment is high. HIV-negative, non-pregnant Rwandan BV patients were randomized to four groups (n = 17/group) after seven-day oral metronidazole treatment: behavioral counseling only (control), or counseling plus intermittent use of oral metronidazole, Ecologic Femi+ vaginal capsule (containing multiple Lactobacillus and one Bifidobacterium species), or Gynophilus LP vaginal tablet (L. rhamnosus 35) for two months. Vaginal microbiota assessments at all visits included Gram stain Nugent scoring and 16S rRNA gene qPCR and HiSeq sequencing. All interventions were safe. BV (Nugent 7-10) incidence was 10.18 per person-year at risk in the control group, and lower in the metronidazole (1.41/person-year; p = 0.004), Ecologic Femi+ (3.58/person-year; p = 0.043), and Gynophilus LP groups (5.36/person-year; p = 0.220). In mixed effects models adjusted for hormonal contraception/pregnancy, sexual risk-taking, and age, metronidazole and Ecologic Femi+ users, each compared to controls, had higher Lactobacillus and lower BV-anaerobes estimated concentrations and/or relative abundances, and were less likely to have a dysbiotic vaginal microbiota type by sequencing. Inter-individual variability was high and effects disappeared soon after intervention cessation. Lactobacilli-based vaginal probiotics warrant further evaluation because, in contrast to antibiotics, they are not expected to negatively affect gut microbiota or cause antimicrobial resistance.


Assuntos
Lactobacillus/fisiologia , Metronidazol/farmacologia , Microscopia , Probióticos/farmacologia , Análise de Sequência , Vaginose Bacteriana/microbiologia , Vaginose Bacteriana/prevenção & controle , Administração Intravaginal , Adolescente , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Feminino , Humanos , Lactobacillus/genética , Metronidazol/administração & dosagem , Pessoa de Meia-Idade , Projetos Piloto , Prevenção Secundária , Adulto Jovem
20.
BMC Vet Res ; 16(1): 34, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32013961

RESUMO

BACKGROUND: Campylobacter spp. are a major cause of bacterial food-borne diarrhoeal disease. This mainly arises through contamination of meat products during processing. For infection, Campylobacter spp. must adhere to epithelial cells of the mucus layer, survive conditions of the gastrointestinal tract, and colonise the intestine of the host. Addition of probiotic bacteria might promote competitive adhesion to epithelial cells, consequently reducing Campylobacter jejuni colonisation. Effect of Lactobacillus spp. (PCS20, PCS22, PCS25, LGG, PCK9) on C. jejuni adhesion, invasion and translocation in pig (PSI cl.1) and chicken (B1OXI) small-intestine cell lines, as well as pig enterocytes (CLAB) was investigated. RESULTS: Overall, in competitive adhesion assays with PSI cl.1 and CLAB cell monolayers, the addition of Lactobacillus spp. reduced C. jejuni adherence to the cell surface, and negatively affected the C. jejuni invasion. Interestingly, Lactobacillus spp. significantly impaired C. jejuni adhesion in three-dimensional functional PSI cl.1 and B1OXI cell models. Also, C. jejuni did not translocate across PSI cl.1 and B1OXI cell monolayers when co-incubated with probiotics. Among selected probiotics, Lactobacillus rhamnosus LGG was the strain that reduced adhesion efficacy of C. jejuni most significantly under co-culture conditions. CONCLUSION: The addition of Lactobacillus spp. to feed additives in livestock nutrition might be an effective novel strategy that targets Campylobacter adhesion to epithelial cells, and thus prevents colonisation, reduces the transmission, and finally lowers the incidence of human campylobacteriosis.


Assuntos
Aderência Bacteriana , Translocação Bacteriana , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/fisiologia , Lactobacillus/fisiologia , Animais , Infecções por Campylobacter/fisiopatologia , Campylobacter jejuni/crescimento & desenvolvimento , Linhagem Celular , Galinhas , Células Epiteliais/microbiologia , Probióticos , Suínos
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