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Variations in gut microbiota might impact metabolism leading to body weight excess. We assessed the impact of a probiotic supplementation in pediatric obesity on weight, metabolic alterations, selected gut microbial groups, and functionality. Cross-over, double-blind, randomized control trial (BIFI-OBESE trial; NCT03261466). 101 youths (6–18 years, Tanner stage ≥2) with obesity and insulin-resistance on diet were randomized to 2 × 109 CFU/AFU/day of Bifidobacterium breve BR03 (DSM 16604) and B. breve B632 (DSM 24706) (51) or placebo (50) for 8 weeks with a 4-weeks wash-out period. All subjects (M/F 54/47) completed the first 8 weeks, and 82 (M/F 43/39) the last part without adverse events. Mixed-effects models revealed a carry-over effect on many variables in the entire study, narrowing the analysis to the first 8 weeks before the wash-out periods. All subjects improved metabolic parameters, and decreased weight and Escherichia coli counts. Probiotics improved insulin sensitivity at fasting (QUICKI, 0.013 CI95%0.0–0.03) and during OGTT (ISI, 0.654 CI95%-0.11–1.41). Cytokines, GLP1, and target microbial counts did not vary. Of 25 SCFAs, acetic acid and acetic acid pentyl-ester relative abundance remained stable in the probiotics, while increased in the placebo (p < 0.02). A signature of five butanoic esters identified three clusters, one of them had better glucose responses during probiotics. An 8 weeks treatment with B. breve BR03 and B632 had beneficial effects on insulin sensitivity in youths with obesity. Microbiota functionality could influence metabolic answers to probiotics. Long-term studies to confirm and enrich our findings are justified. Tailored probiotic treatments could be an additional strategy for obesity. NCT03261466. [ABSTRACT FROM AUTHOR]

Celiac disease (CD) is an immune-mediated systemic disease, caused by ingestion of gluten in genetically predisposed individuals. Gut microbiota dysbiosis might play a significant role in pathogenesis of chronic enteropathies and its modulation can be used as an intervention strategy in CD as well. In this study, we aimed to identify correlations between fecal microbiota, serum tumor necrosis factor alpha (TNF-α) and fecal short-chain fatty acids (SCFAs) in healthy children and children with CD after administration of probiotic Bifidobacterium breve BR03 and B632. A double-blind placebo-controlled study enrolled 40 children with CD (CD) and 16 healthy children (HC). CD children were randomly allocated into two groups, of which 20 belonged to the placebo (PL) group and 20 to the Probiotic (PR) group. The PR group received a probiotic formulation containing a mixture of 2 strains, B. breve BR03 (DSM 16604) and B. breve B632 (DSM 24706) in 1:1 ratio for 3 months. Subsequently, for statistical analysis, blood and fecal samples from CD children (on enrolment - T0 and after 3 months, at the end of intervention with probiotic/placebo - T1) and HC children were used. The HC group was sampled only once (T0). Verrucomicrobia , Parcubacteria and some yet unknown phyla of Bacteria and Archaea may be involved in the disease, indicated by a strong correlation to TNF-α. Likewise, Proteobacteria strongly correlated with fecal SCFAs concentration. The effect of probiotic administration has disclosed a negative correlation between Verrucomicrobia , some unknown phyla of Bacteria , Synergistetes , Euryarchaeota and some SCFAs, turning them into an important target in microbiome restoration process. Synergistetes and Euryarchaeota may have a role in the anti-inflammatory process in healthy human gut. Our results highlight new phyla, which may have an important relation to disease-related parameters, CD itself and health. [ABSTRACT FROM AUTHOR]

Abstract Social bees harbor a community of gut mutualistic bacteria, among which bifidobacteria occupy an important niche. Recently, four novel species have been isolated from guts of different bumblebees, thus allowing to suppose that a core bifidobacterial population may be present in wild solitary bees. To date there is sparse information about bifidobacteria in solitary bees such as Xylocopa and Osmia spp., this study is therefore focused on the isolation and characterization of bifidobacterial strains from solitary bees, in particular carpenter bee (Xylocopa violacea), builder bee (Osmia cornuta), and red mason bee (Osmia rufa). Among the isolates from Osmia spp. no new species have been detected whereas among Xylocopa isolates four strains (XV2, XV4, XV10, XV16) belonging to putative new species were found. Isolated strains are Gram-positive, lactate- and acetate-producing and possess the fructose-6-phosphate phosphoketolase enzyme. Full genome sequencing and genome annotation were performed for XV2 and XV10. Phylogenetic relationships were determined using partial and complete 16S rRNA sequences and hsp60 restriction analysis that confirmed the belonging of the new strains to Bifidobacterium genus and the relatedness of the strains XV2 and XV10 with XV16 and XV4, respectively. Phenotypic tests were performed for the proposed type strains, reference strains and their closest neighbor in the phylogenetic tree. The results support the proposal of two novel species Bifidobacterium xylocopae sp. nov. whose type strain is XV2 (=DSM 104955T = LMG 30142T), reference strain XV16 and Bifidobacterium aemilianum sp. nov. whose type strain is XV10 (=DSM 104956T = LMG 30143T), reference strain XV4. [ABSTRACT FROM AUTHOR]

Bergamot whole-fruit powder was analyzed for total polyphenols, flavonoids, flavonols and ascorbic acid content and tested for in vitro and ex vivo antioxidant activity. The flavonoids profile was further characterized via HPLC-DAD-MS/MS and the most abundant flavonoids were quantified. The antimicrobial activity against potentially pathogenic bacteria and the effect on beneficial gut bacteria were determined. Lastly, we evaluated the effects of bergamot extract on endothelial alterations in LPS-stimulated human microvascular endothelial cells (HMEC-1). Our data demonstrated that bergamot powder possesses in vitro and ex vivo antioxidant activity, shows a selective inhibition against pathogenic strains and growth stimulation effects on some beneficial gut bacteria. Moreover, it protects HMEC-1 from LPS-induced activation and dysfunction and reduces the resulting endoplasmic reticulum stress. The relationship between isolated flavonoids and the protective effects are discussed. In conclusion, bergamot whole-fruit powder possesses beneficial health effects that makes it a potentially useful material for the nutraceutical industry. [ABSTRACT FROM AUTHOR]

In meat fermented foods, Clostridium spp. growth is kept under control by the addition of nitrite. The growing request of consumers for safer products has led to consider alternative bio-based approaches, the use of protective cultures being one of them. This work is aimed at checking the possibility of using two Lactobacillus spp. strains as protective cultures against Clostridium spp. in pork ground meat for fermented salami preparation. Both Lactobacillus strains displayed anti-clostridia activity in vitro using the spot agar test and after co-culturing them in liquid medium with each Clostridium strain. Only one of them, however, namely L . plantarum PCS20, was capable of effectively surviving in ground meat and of performing anti-microbial activity in carnis in a challenge test where meat was inoculated with the Clostridium strain. Therefore, this work pointed out that protective cultures can be a feasible approach for nitrite reduction in fermented meat products. [ABSTRACT FROM AUTHOR]

New antimicrobial (AM) coatings based on imidazolium salts have been prepared linking the imidazolium salts to the cotton fabric using siloxane oligomers as coupling agents. Three different imidazolium salts, linked to the siloxane oligomers connected to the cotton fabric either with ionic or covalent linkages, have been used. FTIR analysis shows that the imidazolium salts are linked to the cotton fabric. All the coatings prepared have high antimicrobial activity at both concentrations tested (3 and 10 wt%) and against a Gram positive and a Gram negative bacterium. The AM activity is mainly retained after 4 cycles of washing. [ABSTRACT FROM AUTHOR]

The conversion of rainforests to plantations leads to about 50% loss in the organic carbon (C) content of the soil and strongly influences nitrogen (N) cycling, potentially increasing greenhouse gas emissions. However, the effect of land-use change in forests on the microbial communities responsible for C and N cycling processes remains poorly understood. This study quantified C and N fractions of soil organic matter in a tropical forest, rubber agroforestry system, 5- and 15-year-old rubber plantations. The community structure and abundance of fungi and bacteria were studied using high-throughput sequencing and q-PCR. Forest conversion substantially altered community structure and abundance of microbial communities. Rainforest conversion to plantation enhanced bacterial diversity and reduced the soil C mineralization rate. In addition, land-use change also enhanced the soil N mineralization rate in 5-year-old rubber plantation and agroforestry system. A structural equation modelling suggested that soil microbial communities played more dominant roles in driving the shift in C and N cycles caused by land-use change than soil C and N pools. These mechanistic insights into the differential control of soil fungal and bacterial communities on C and N mineralization has implications for managing land-use changes in tropical forest ecosystems. • Rainforest conversion into rubber-based plantations decreased soil C and N pools. • Bacterial abundance was reduced but oligotrophic bacteria are less affected by land-use change. • Land-use change increased relative abundance of fungi. • Shifts in the soil bacterial and fungal communities explained ecosystem functions. [ABSTRACT FROM AUTHOR]

The main crude polysaccharides (CPS), extracted from two widely cultivated pomegranate varieties, Laffan and Wonderful, were studied and characterized. We obtained the highest CPS extraction yield (approximatively 10% w/w on dried matter) by 1 h of decoction (ratio 1/40 w/v). The predominant polymers (75–80%) of the CPS samples showed a hydrodynamic volume close to 2000 kDa by size exclusion chromatography and the exocarp and mesocarp profiles were very similar. The proton spectra ( 1 H NMR), according to sugar composition and gelling ability, confirmed the main polysaccharide fractions were pectin with different acylation and methylation degree. The CPS from Laffan and Wonderful mesocarp showed prebiotic properties in vitro with Lactobacillus and Bifidobacterium strains. The composition of the decoction (12% ellagitannins and 10% of CPS) obtained by a green extraction process of pomegranate by-products, makes it a suitable component of functional food formulations. [ABSTRACT FROM AUTHOR]

C. jejuni is considered a food safety concern to both public health authorities and consumers since it is the leading bacterial cause of food-borne gastroenteritis in humans. A high incidence of C. jejuni in broiler flocks is often correlated to pathogen recovery in retail poultry meat, which is the main source of human infection. In this work broiler chickens were fed with a synbiotic product mixed with conventional feed using two different administration strategies. The synbiotic was formulated with the microencapsulated probiotic Bifidobacterium longum PCB133 and a xylo-oligosaccharide (XOS). 1-day old chicks were infected with C. jejuni strain M1 (10 5 cells) and the synbiotic mixture was then administered starting from the first and the 14th day of chicken life (for animal groups GrpC and GrpB respectively). The goal of this study was to monitor C. jejuni load at caecum level at different sampling time by real-time PCR, identifying the best administration strategy. The microbiological analysis of the caecal content also considered the quantification of Campylobacter spp., Bifidobacterium spp. and B. longum . The supplemented synbiotic was more successful in reducing C. jejuni and Campylobacter spp. when administered lifelong, compared to the shorter supplementation (GrpB). Bifidobacterium spp. quantification did not show significant differences among treatments and B. longum PCB133 was detected in both supplemented groups evidencing the successful colonization of the strain. Moreover, the samples of the control group (GrpA) and GrpC were analysed with PCR-denaturing gradient gel electrophoresis (PCR-DGGE) to compare the caecal microbial community profiles at the beginning and at the end of the trial. Pattern analysis evidenced the strong influence of the early synbiotic supplementation, although a physiological change in the microbial community, occurring during growth, could be observed. Experimental results demonstrate that the synbiotic approach at farm level can be an effective strategy, combined with biosecurity measures, to improve the safety of poultry meat. [ABSTRACT FROM AUTHOR]

We performed a 18-month experiment on 0.496 m 3 pots filled with a sandy soil in which 1-year old nectarine trees were grown. With four replicates, the following amendment strategies were compared: a) unamended control; b) biochar (20 g fw kg −1 ); c) compost (76.8 g fw kg −1 ) and d) biocompost (mixing biochar and compost at the same rates of the previous two strategies). Amendments were applied at planting and only unamended and merely biochar-amended soils were fertilized with mineral inputs. Soil mineral N availability was regularly measured and at the end of the experiment, we determined total C and N concentration of soils and aged biochar fragments. Total soil respiration (R TOT ) was separated into soil organic-C derived (R SOC ) and rhizosphere (R R ) respiration by the trenching method. Total soil DNA was extracted from samples collected after 6 and 18 months and bacterial community analysis was carried out by denaturing gradient gel electrophoresis (DGGE). Expression of nitrification key genes of ammonia monooxygenase (AMO) and nitrite oxidoreductase (NOR) and the relative abundance of specific bacterial community ( Nitrosomonas spp. and Nitrobacter spp.) were determined by Real Time PCR on soil samples collected at 6, 12, 15, 16 and 18 months since amendments incorporation. The addition of compost significantly promoted soil mineral N, bacterial diversity and the relative expression of nitrification process related key genes. Furthermore, compost enhanced R SOC likely due to the stimulation of the microbial community by providing labile C sources. Conversely, changes due to the mere addition of biochar were negligible. However, biochar had no detrimental effects, rather it promoted gene expression involved in the nitrification process. A synergic effect between the two amendments emerged in the total soil C and N concentration and in the R SOC , leading to a significantly higher cumulative CO 2 . Although the source of the additional CO 2 rate remains uncertain, a priming effect induced by biochar on the labile compost-derived C-fractions is hypothesized. Compost reduced the relative richness of Arthrobacter spp. in soil, while Actinomadura flavalba , Saccharomonospora viridis , Thermosporomyces composti and Enterobacter spp. were peculiar of the biocompost profile which increased band richness. Biocompost significantly increased the relative abundance of Nitrosomonas spp. and Nitrobacter spp. and both AMO and NOR key genes expression levels. The mixture of biochar and compost seems effective to induce agronomical benefits, although environmental concerns (e.g. additional CO 2 emissions) require further investigations. [ABSTRACT FROM AUTHOR]

• Harvested fruits from wastewater-irrigated tree are exempt of fecal-borne pathogens. • Heavy metals did not accumulate in fruit and leaves of wastewater-irrigated trees. • Endophytic bacteria increased in shoot irrigated with wastewater. • No E. coli was found neither in apple nor in nectarine shoot/fruit. • E. coli internalized but did not migrate to the epigeal part of plants (shoot). The use of secondary treated wastewater (STW) for irrigation is considered as a strategy to mitigate water shortage in summer periods. Unfortunately, the utilization of STW in agriculture is not exempt from environmental and health risks, being a potential source of toxic chemicals (e.g. heavy metals) and human pathogens (e.g. Salmonella spp. and Escherichia coli). The aim of this work is to verify whether irrigation of apple and nectarine trees with STW may lead to heavy metal and microbial contamination in shoot, leaf and fruit tissues. Three-year old trees were grown in pots and drip irrigated separately, for one season, using either tap water (TW) or STW. STW irrigation did not affect heavy metal and trace element concentration (e.g. B, Na, Zn) both in leaves and fruits. Heavy metal concentrations in fruit tissues were lower than international limits for human consumption in both species. Independently from the species, the total bacterial count (TBC) on shoot was almost the double in STW irrigated plants compared to the TW-irrigated ones. No E. coli was found in shoot and fruit; few coliforms (TC) were detected in shoot tissues and in nectarine fruits, far below European microbiological limits for foodstuff. Finally, a laboratory trial, aimed at evaluating possible mechanisms of E. coli translocation inside plants, was carried out on 3-month old peach rootstock plants (i.e. GF 677), artificially inoculated with two E. coli strains, characterized by a different level of pathogenicity (disarmed DH5α and E. coli 1576). Populations of both E. coli strains were isolated as epiphytic and as endophytic only at root level. Nonetheless, the endophytic population of the E. coli 1576 was generally higher than the DH5α strain. Colonization of the epigeal part was never observed. These results are promising for the use of STW, especially for drip irrigated orchards, since water does not wet the canopy and consequently the final product. [ABSTRACT FROM AUTHOR]

Poly(ricinoleic acid) (PRA), coming from the self-polycondensation of ricinoleic acid (RA), which derives from castor oil, is a very interesting polymer because of its intrinsic antimicrobial activity. However, its mechanical properties are insufficient for whatever application, thus copolymerization is required. In this work, two polyesters based on 1,3 propanediol (PD), such as poly(propylene terephthalate) (PPT) and poly(propylene isophthalate) (PPI), were chosen to prepare random copolyesters containing ricinoleate units. Different content of RA have been tested, such as 10 and 25 mol% respect to the comonomer (terephthalic or isophthalic dimethylester), to evaluate the lowest composition able to confer antibacterial activity. The materials were tested against Staphylococcus aureus and Escherichia coli , and 25 mol% of RA unit resulted to impart antimicrobial activity. Furthermore, thermal properties (DSC and TGA) as well as the elastomeric response of films were investigated. The copolymer PPI/PRA containing 10 mol% of RA presents very high elongation at break, around 1300%. Therefore, by tuning the RA amount it is possible to obtain outstanding elastomeric or antibacterial materials, suitable for textiles and/or film engineering applications. • Ricinoleic acid from biomass is suitable to be used in polycondensation reactions. • Copolymers properties can be tuned as a function of ricinoleic acid content. • Copolymers richest in ricinoleic acid have significant antibacterial activity. • The copolymer of PPI containing 10 mol% of ricinoleic acid unit presents very high elongation at break. • Copolymers with ricinoleic acid could be suitable for textile fibers and/or film engineering thermoplastic applications. [ABSTRACT FROM AUTHOR]

Polybutylene succinate (PBS) were processed in melt extrusion by dispersion of organo-modified layered double hydroxide (LDH). Depending on the organic anion interleaved into LDH fillers (L-tyrosine (TYR), L-tryptophan (TRP), L-ascorbate (ASA) and 3-(4-hydroxyphenyl)propionate (HPP)), it was possible to control and tune the properties of the resulting PBS composites. Each LDH filler is found to act differently toward PBS, thus modifying its viscoelastic properties (as expressed by a chain extending effect), its rate of hydrolysis and photo-degradation or its antibacterial activity. The highest chain extending effect was observed in the case of LDH with L-tryptophan, the worst – with L-ascorbate anion. However, L-ascorbate anions interleaved into LDH present 100% activity in antibacterial properties. A better compromise may be achieved when PBS is mixed with different LDHs such as those combining HPP and ASA, making possible to target efficiently multi-properties such as small rate of hydrolysis, photo-stability, biocide activity as well as chain extension, thus turning to a multifunctional (bio)nanocomposites with new possible applications. Finally, a possible scale-up is demonstrated on thin films. Unlabelled Image • Organo-modified LDH as filler for bio-based polyester. • LDH hybrid filler endowing polymer with multi-functionality. • Chain extension and stability against UV, hydrolysis and bacteria. • Enhanced processability and durability of the polymer composite. • Scale-up and applicability addressed. [ABSTRACT FROM AUTHOR]