Search

Several studies have outlined that changes in the honeybee gut microbial composition may impair important metabolic functions supporting the honeybees' life. Gut dysbiosis may be caused by diseases like Nosema ceranae or by other anthropic, environmental or experimental stressors. The present work contributes to increasing knowledge on the dynamics of the gut microbiome acquisition in caged honeybees, an experimental condition frequently adopted by researchers, with or without infection with N. ceranae, and fed with a bacterial mixture to control N. ceranae development. Changes of the gut microbiota were elucidated comparing microbial profile of caged and open-field reared honeybees. The absolute abundance of the major gut microbial taxa was studied with both NGS and qPCR approaches, whereas changes in the functionality were based on RAST annotations and manually curated. In general, all caged honeybees showed important changes in the gut microbiota, with γ -proteobacteria (Frischella, Gilliamella and Snodgrassella) lacking in all caged experimental groups. Caged honeybees infected with N. ceranae showed also a strong colonization of environmental taxa like Citrobacter, Cosenzaea and Morganella, as well as possibly pathogenic bacteria such as Serratia. The colonization of Serratia did not occur in presence of the bacterial mixture. The functionality prediction revealed that environmental bacteria or the supplemented bacterial mixture increased the metabolic potential of the honeybee gut microbiome compared to field and caged controls. [ABSTRACT FROM AUTHOR]

This review is aimed at describing the most recent advances in the gut microbiota composition of newborns and infants with a particular emphasis on bifidobacteria. The newborn gut microbiota is quite unstable, whereas after weaning, it becomes more stable and gets closer to the typical adult microbiota. The newborn and infant gut microbiota composition is impaired in several enteric and non-enteric pathologies. The core of this review is the description of the most recent documented applications of bifidobacteria to newborns and infants for their prevention and treatment. Acute diarrhea is the most studied disease for which bifidobacteria are applied with great success, Bifidobacterium longum and Bifidobacterium breve being the most applied species. Moreover, the most recent updates in the use of bifidobacteria for the prevention and treatment of pathologies typical of newborns, such as necrotizing enterocolitis, colics, and streptococcal infections, are presented. In addition, a number of not strictly enteric pathologies have in recent years evidenced a strict correlation with an aberrant gut microbiota in infants, in particular showing a reduced level of bifidobacteria. These diseases represent new potential opportunities for probiotic applications. Among them, allergic diseases, celiac disease, obesity, and neurologic diseases are described in this review. The preliminary use of bifidobacteria in in vitro systems and animal models is summarized as well as preliminary in vivo studies. Only after validation of the results via human clinical trials will the potentiality of bifidobacteria in the prevention and cure of these pathologies be definitely assessed. [ABSTRACT FROM AUTHOR]

4-Nonylphenol (4-NP) isomers are toxic and recalcitrant compounds often resulting, together with short-chain ethoxylated nonylphenol (NP nEO, where n is the number of ethylene oxide units), from NP nEO biodegradation in conventional activated sludge plants. In this work, a microbial consortium, defined as Consortium A, capable of removing 100 mg/L of 4-NP with no accumulation of metabolites with aromatic moiety was isolated from textile wastewaters after enrichment with 4-NP. The consortium showed remarkable degradation activities toward several short-chain NP nEO congeners. Culture-dependent techniques were used to isolate from the consortium twenty-six strains assigned to seven different amplified ribosomal DNA restriction analysis groups. Two- and three-member cocultures were prepared with the strains showing highest 4-NP-degrading capabilities, but neither the single strains nor the cocultures were as efficient in 4-NP degradation as Consortium A. FISH was used to characterize the microbial composition of Consortium A: it evidenced a strong occurrence of Proteobacteria and, in particular, of Gammaproteobacteria along with a relevant stability of the culture. Therefore, the isolated consortium has the potential of being used in the development of a biotechnological process for the tertiary treatment of effluents of activated sludge plants fed with NP nEO-contaminated wastewaters. [ABSTRACT FROM AUTHOR]

An aerobic bacterium (BCc6), isolated from nonylphenol polyethoxylates (NPEOs)-contaminated sludge, was shown to be capable of degrading low-ethoxylated NPEO mixtures. Sequencing of 16S rRNA gene (rDNA) showed that it clustered with Stenotrophomonas nitritireducens. Fluorescent in situ hybridization (FISH), performed on BCc6 strain and on the previously isolated Stenotrophomonas BCaL2, also involved in NPEO degradation but clustering with S. maltophilia, showed that strain BCc6 did not hybridize with the S. maltophilia-specific probe, and neither of the two strains hybridized with probes targeted to the Gammaproteobacteria site, rDNA analyses performed on the two strains evidenced two new polymorphisms, the first one at the 23S rRNA Gammaproteobacteria site, characterizing the known members of the Stenotrophomonas genus, and the other one at the 16S rRNA level, characteristic of S. nitritireducens. Two new FISH probes were designed accordingly, tested on control bacterial cultures, and employed for in situ monitoring of Stenotrophomonas representatives. [ABSTRACT FROM AUTHOR]

Intensive conventional farm management, characterized by high agrochemicals input, could alter the composition of microbial communities with potential negative effects on both functional traits and the ecosystem services provided. In this study, we investigated the gut microbial composition of a high ecological relevance carabid Pseudoophonus rufipes, sampled in two fields subjected to conventional and organic management practices. Carabids' gut microbiota was analyzed via qPCR and NGS. Profound differences between the microbial composition of organic and conventional samples were detected: the abundance of Tenericutes and Proteobacteria was significant higher in organic and conventional samples, respectively. Spiroplasmataceae and Bifidobacteriaceae families were significantly more abundant in samples from organic management, while Enterococcaceae, Morganellaceae and Yersiniaceae were more abundant in samples from conventional management. The diverse gut microbial composition of insects between the two management systems is related to the pressure of environmental stressors and it may representing an important bioindication of ecological functions and services provided by a carabid species. [ABSTRACT FROM AUTHOR]

Background and aims: As potent allelochemicals, flavonoids are believed to be associated with the development of soil-borne diseases. Fusarium species infection is responsible for soybean [Glycine max(L.) Merr.] root rot. However, it is uncertain if and how flavonoids influence rhizosphere Fusarium communities under consecutive soybean monoculture. Methods: Quantitative real-time PCR and pyrosequencing were used to study the Fusarium community. Spectrophotometric techniques and ultra-performance liquid chromatography (UPLC) were used to quantify flavonoids and daidzein and genistein levels, respectively. Results: In field soil, the sizes of Fusarium community were higher from 6 to 13 years monoculture than from 1 to 3 years. The abundance of Fusarium community was significantly positively correlated with rhizosphere concentrations of the flavonoids and isoflavonoids daidzein and genistein levels. Consecutive monocultured soil selectively inhibited or stimulated certain Fusarium species, F. oxysporum remaining the most abundant. The application of daidzein and a mixture of daidzein and genistein to soil affected the Fusarium community depending on the incubation time and ranging from inhibition to promotion over time. Conclusions: Consecutive soybean monoculture results in shifts in the composition and size of rhizosphere Fusarium community. The Fusarium community was strongly influenced by total flavonoids, in particular daidzein and genistein, rather than soil properties. [ABSTRACT FROM AUTHOR]

Nowadays, honey bees are stressed by a number of biotic and abiotic factors which may compromise to some extent the pollination service and the hive productivity. The EU ban of antibiotics as therapeutic agents against bee pathogens has stimulated the search for natural alternatives. The increasing knowledge on the composition and functions of the bee gut microbiota and the link between a balanced gut microbiota and health status have encouraged the research on the use of gut microorganisms to improve bee health. Somehow, we are assisting to the transfer of the 'probiotic concept' into the bee science. In this review, we examine the role of the honey bee gut microbiota in bee health and critically describe the available applications of beneficial microorganisms as pest control agents and health support. Most of the strains, mainly belonging to the genera Lactobacillus, Bifidobacterium and Bacillus, are isolated from honey bee crop or gut, but some applications involve environmental strains or formulation for animal and human consumption. Overall, the obtained results show the favourable effect of applied microbial strains on bee health and productivity, in particular if strains of bee origin are used. However, it is actually not yet possible to conclude whether this strategy will ever work. In particular, many aspects regarding the overall setup of the experiments, the dose, the timing and the duration of the treatment need to be optimized, also considering the microbiological safety of the hive products (i.e. pollen and honey). In addition, a deep investigation about the effect on host immunity and physiology is envisaged. Lastly, the final users of the formulations, i.e. beekeepers, should be taken into account for the achievement of high-quality, cost-effective and easy-to-use products. [ABSTRACT FROM AUTHOR]

Different factors are known to influence the early gut colonization in newborns, among them the perinatal use of antibiotics. On the other hand, the effect on the baby of the administration of antibiotics to the mother during labor, referred to as intrapartum antibiotic prophylaxis (IAP), has received less attention, although routinely used in group B Streptococcus positive women to prevent the infection in newborns. In this work, the fecal microbiota of neonates born to mothers receiving IAP and of control subjects were compared taking advantage for the first time of high-throughput DNA sequencing technology. Seven different 16S rDNA hypervariable regions (V2, V3, V4, V6 + V7, V8, and V9) were amplified and sequenced using the Ion Torrent Personal Genome Machine. The results obtained showed significant differences in the microbial composition of newborns born to mothers who had received IAP, with a lower abundance of Actinobacteria and Bacteroidetes as well as an overrepresentation of Proteobacteria. Considering that the seven hypervariable regions showed different discriminant ability in the taxonomic identification, further analyses were performed on the V4 region evidencing in IAP infants a reduced microbial richness and biodiversity, as well as a lower number of bacterial families with a predominance of Enterobacteriaceae members. In addition, this analysis pointed out a significant reduction in Bifidobacterium spp. strains. The reduced abundance of these beneficial microorganisms, together with the increased amount of potentially pathogenic bacteria, may suggest that IAP infants are more exposed to gastrointestinal or generally health disorders later in age. [ABSTRACT FROM AUTHOR]

Background: Increasing evidence suggests that not only genetics, but also environmental factors like gut microbiota dysbiosis play an important role in the pathogenesis of celiac disease (CD).Aim: The aim of our study was to investigate the effect of two probiotic strains Bifidobacterium breve BR03 and B. breve B632 on serum production of anti-inflammatory cytokine interleukin 10 (IL-10) and pro-inflammatory cytokine tumor necrosis factor alpha (TNF-α) in children with CD.Methods: The study was a double-blinded, placebo-controlled trial that included 49 children with CD on gluten-free diet (GFD) randomized into two groups and 18 healthy children in the control group. The first group (24 children with CD) daily received B. breve BR03 and B632 (2 × 10(9) colony-forming units) and the second group (25 children with CD) received placebo for 3 months.Results: TNF-α levels were significantly decreased in the first group after receiving B. breve for 3 months. On follow-up, 3 months after receiving probiotics, TNF-α levels increased again. Children with CD who were on GFD for less than 1 year showed similar baseline TNF-α levels as children who were on GFD for more than 1 year. IL-10 levels were in all groups of patients below detection level.Conclusions: Probiotic intervention with B. breve strains has shown a positive effect on decreasing the production of pro-inflammatory cytokine TNF-α in children with CD on GFD. [ABSTRACT FROM AUTHOR]