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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]

Abstract: Vanillin is one of the most important flavors in the food industry and there is great interest in its production through biotechnological processes starting from natural substrates such as ferulic acid. Among bacteria, recombinant Escherichia coli strains are the most efficient vanillin producers, whereas Pseudomonas spp. strains, although possessing a broader metabolic versatility, rapidly metabolize various phenolic compounds including vanillin. In order to develop a robust Pseudomonas strain that can produce vanillin in high yields and at high productivity, the vanillin dehydrogenase (vdh)-encoding gene of Pseudomonas fluorescens BF13 strain was inactivated via targeted mutagenesis. The results demonstrated that engineered derivatives of strain BF13 accumulate vanillin if inactivation of vdh is associated with concurrent expression of structural genes for feruloyl-CoA synthetase (fcs) and hydratase/aldolase (ech) from a low-copy plasmid. The conversion of ferulic acid to vanillin was enhanced by optimization of growth conditions, growth phase and parameters of the bioconversion process. The developed strain produced up to 8.41mM vanillin, which is the highest final titer of vanillin produced by a Pseudomonas strain to date and opens new perspectives in the use of bacterial biocatalysts for biotechnological production of vanillin from agro-industrial wastes which contain ferulic acid. [Copyright &y& Elsevier]

Abstract: An aerobic bacterial consortium (Consortium A) was recently obtained from textile wastewater and was capable of degrading 4-nonylphenol and nonylphenol polyethoxylates (NPnEOs). In the perspective of developing a biotechnological process for the treatment of effluents from activated sludge plants fed with NPnEO contaminated wastewater, the capability of Consortium A of biodegrading an industrial mixture of NPnEOs in the physiological condition of immobilized cells was investigated. Two identically configured packed bed reactors were developed by immobilizing the consortium on silica beads or granular activated carbon. Both reactors were tested in batch and continuous mode by feeding them with water supplemented with NPnEOs. The two reactors were monitored through chemical, microbiological and molecular integrated methodology. Active biofilms were generated on both immobilization supports. Both reactors displayed comparable NPnEO mineralization under batch and continuous conditions. FISH analyses evidenced that the biofilms evolved with time by changing the reactor operation mode and the organic load. Taken together, the data collected in this study provide a preliminary strong indication on the feasibility of Consortium A-based biofilm technology for the decontamination of NPnEO containing effluents. [Copyright &y& Elsevier]

Abstract: The fine specialty chemicals production from agro-industrial by-products such as cereal bran is a topic of high interest in wheat-producing countries. In this work, the possibility of obtaining vanillin from bioconversion of ferulic acid derived from enzymatic hydrolysis of wheat bran was explored. Freely available ferulic acid was first obtained through wheat bran hydrolysis by using commercially available, technical-grade enzyme preparations. Then, resting cells of an engineered E. coli strain, JM109(pBB1), containing the genes responsible for conversion of ferulic acid into vanillin, were used to transform ferulic acid available in the hydrolyzed mixture into vanillin. A vanillin molar yield of 50% was obtained, but most of the vanillin produced was reduced to vanillyl alcohol. The purification of the hydrolyzate with a ionic exchange resin to remove most of the carbohydrates allowed to obtain both higher bioconversion yields (up to 70%) and lower vanillin reduction. This is the first work in which vanillin is produced from ferulic acid obtained through wheat bran hydrolysis. The results obtained demonstrate the potential application of the proposed strategy in vanillin biosynthesis from agro-industrial by-products. [Copyright &y& Elsevier]

Three bacterial strains were isolated from activated sludge samples of two treatment plants receiving domestic and industrial wastewaters containing polyethoxylated nonylphenols. One strain (VA160) was isolated on rich medium, and the other two (BCaL1 and BCaL2) on mineral medium containing two industrial mixtures of nonylphenol ethoxylates as the sole carbon source. Strain VA160 was a Gram-positive, spore forming, filamentous bacterium, producing aggregates during growth in liquid medium. On the basis of phylogenetic analysis the strains were assigned to the Bacillus (VA160), Acinetobacter (BCaL1) and Stenothrophomonas (BCaL2) genera. High performance liquid chromatography analysis showed that only the Acinetobacter and Stenothrophomonas strains were involved in the degradation of polyethoxylated nonylphenols. Bacillus VA160, however, when co-cultured with the two degrading strains, induced the formation of cell aggregates and facilitated NPEO degradation. Fluorescent in situ hybridisation on the activated sludge sample from which Bacillus VA160 was isolated, using probes for Gram-positive bacteria with low G+C content, showed that bacteria belonging to this group specifically occurred inside the examined flocs. These observations suggest that the enhanced biodegradation of polyethoxylated nonylphenols in the three-membered co-culture is favoured by VA160-induced aggregation of BcaL1 and BcaL2 cells involved in the process. [Copyright &y& Elsevier]

The development of eco-friendly polymer composites with multifunctional properties aligns with the goals of the circular economy agenda, which aims to minimize waste and promote the sustainable use of resources by closing the loop of product life cycles. Eco-friendly polymer composites play a crucial role in achieving these objectives. The present work focuses on the preparation of fully biobased blends obtained by melt mixing a bio-polyester, poly(butylene succinate- co -adipate) (PBSA), with orange peels up to 20 wt%, to yield active polymer composites. Orange peels, employed here as natural filler, are largely available from food wastes, they are rich in phenolic compounds and possess antioxidant activity as shown by the experimental tests carried out. The thermal stability of the formulated composites is almost unchanged by the filler addition, showing only a slight decrease of the crystallization temperatures and crystalline fraction within the composites. The mechanical properties of the compounds evidence an increase in the elastic modulus together with a decrease in the tensile strength, while the elongation at break remains almost constant. The incorporation of the natural filler enabled the integration of antioxidant and antibacterial properties, which were absent in the original pristine polymer. • PBSA containing up to 20 wt% of orange peels have good antioxidant and antibacterial properties. • Biocomposites formulated with orange peels are found to retain good mechanical properties in terms of elongation at break. • The thermoplastic material produced can be used in the packaging industry or in the organic or integrated farming sector application. [ABSTRACT FROM AUTHOR]

In order to meet the increasing demand for food quality and safety, the control of pathogenic microorganisms from “farm to fork” is a continuous challenge. This challenge has become more important due to changes in animal production, product processing and distribution, new food habits, higher numbers of consumers at risk for infection and increased awareness. This review is focused on the use of protective and probiotic cultures as “natural” intervention measures to control and prevent the transmission of pathogens along the food chain and on the most used technologies to produce these cultures at the large scale. [ABSTRACT FROM AUTHOR]

Turfgrasses are not only designed for recreation activities, but they also provide beneficial environmental effects and positively influence the human wellness. Their major problems are predisposition to tearing out and microbial diseases. The aim of this study was to investigate whether the inoculation of microorganisms can be effective to improve plant growth and root development of perennial ryegrass, to evaluate new sustainable practice for green preservation. A microorganism-based commercial product was used to amend hydroponically grown Lolium perenne L. and results compared with the use of the same filtered product, a phytohormone solution and an untreated control. Plants were grown for five weeks, shoots cut and measured at one-week interval and, at the end, roots were measured for length and weight. Shoot resistance to tearing out was also tested. Moreover, the main microbial groups present in the product were characterized and the microbial profile of sand and root samples was investigated by PCR-DGGE. The plants treated with the product showed an increased resistance to tearing out with respect to other treatments and roots were longer with respect to the control. Microbial analyses of the product evidenced bacterial and yeast species with plant growth promoting activity, such as Stenothrophomonas maltophilia, Candida utilis and several Lactobacillus species. Some Lactobacillus strains were also found to be able to colonize plant roots. In conclusion, the treatment with microorganisms has a great potential for the maintenance and increased performance of turfgrass surfaces. [ABSTRACT FROM AUTHOR]

Abstract: With the ban of dietary antimicrobial agents, the use of probiotics, prebiotics and synbiotics has attracted a great deal of attention in order to improve intestinal health and control food-borne pathogens, which is an important concern for the production of safe meat and meat products. Recently, Campylobacter jejuni has emerged as a leading bacterial cause of food-borne gastroenteritis in humans, and epidemiological evidences indicate poultry and poultry products as the main source of human infection. This work aimed at the development of a synbiotic mixture capable of modulating the gut microbiota of broiler chickens to obtain an increase of the beneficial bacteria (i.e. bifidobacteria, lactobacilli) and a competitive reduction of C. jejuni. The prebiotic compound used in the mixture was chosen after an in vivo trial: a fructooligosaccharide and a galactooligosaccharide were separately administered to broilers mixed with normal feed at a concentration of 0.5% and 3%, respectively. Quantitative PCR on DNA extracted from fecal samples revealed a significant (p<0.05) increase of Bifidobacterium spp. in broilers treated with the galactooligosaccharide, coupled to a decrease (p<0.05) of Campylobacter spp. The galactooligosaccharide was then combined with a probiotic Bifidobacterium strain (B. longum subsp. longum PCB133), possessing in vitro antimicrobial activity against C. jejuni. The strain was microencapsulated in a lipid matrix to ensure viability into the feed and resistance to stomach transit. Finally, the synbiotic mixture was administered to broiler chickens for 14days mixed with normal feed in order to have an intake of 109 CFU of PCB133/day. Bifidobacterium spp., Lactobacillus spp., Campylobacter spp., B. longum subsp. longum and C. jejuni were quantified in fecal samples. PCB133 was recovered in feces of all animals. C. jejuni concentration in poultry feces was significantly (p<0.05) reduced in chickens administered with the synbiotic mixture. This study allowed to highlight the positive effect of the synbiotic approach for C. jejuni reduction in broiler chickens, which is of fundamental importance for the safety of poultry meat consumers. [Copyright &y& Elsevier]

• Fruits from wastewater-irrigated tree are exempt of fecal-borne pathogens. • Shoot and fruit endophytic bacteria increased in wastewater-irrigated trees. • Transpiration increased shoot endophytic bacteria in wastewater-irrigated trees. • Soil total coliforms and total bacteria counts were unaffected by wastewater. • Soil E. coli was found at low concentrations in wastewater-irrigated trees. Irrigation with wastewater can be a solution to preserve and mitigate freshwater demand, in particular during drought periods. Unfortunately, wastewater, although being treated at different levels, could be a carrier of human pathogens (e.g., E. coli) and potentially contaminate crops for human consumptions. This study investigated the seasonal microbiological concentrations, on soil, shoot and fruit tissues of potted peach trees, following two irrigation treatments: freshwater (FW) and secondary urban wastewater without the final disinfection treatment (SW). E. coli was only detected in SW irrigated soil, whereas total coliforms (TC) and total bacteria counts (TBC) were similar in both treatments throughout the season. Endophytic E. coli, Salmonella spp. and TC were not detected in shoot and fruit, but a higher presence of total bacteria (TBC) was observed in SW-irrigated tree compared to FW-irrigated tree. In particular, SW shoots had a higher load compared to fruits, thus showing a potential effect of leaf transpiration, that promoted the transfer of water-borne bacteria from soil to the epigeal part (shoot). The adoption of low-quality SW (even above the microbiological limits of the European Regulation 2020/741 for wastewater re-use in agriculture), when a drip irrigation method is applied, could be a valid alternative to save fresh water without compromising fruit safety. [Display omitted] [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]

Highlights: [•] Castor oil-derivatives are employed for the synthesis of bio-based polyesters. [•] Polyesters obtained from ricinoleic acid exhibit high biocidal activity. [•] Double bonds are exploited for grafting reaction to improve biocidal properties. [Copyright &y& Elsevier]

Anti-Listeria bacterial starters are highly demanded by the meat industry. Novel bioprotective anti-Listeria starters were searched among Lactobacillus species strains isolated from artisanal sausages. The screening confirmed that anti-Listeria activity is a strain-specific property and yielded only 1 strain (of 36) exhibiting a satisfactory level of inhibition, L. delbrueckii WC0286. This strain was compared with two commercial bioprotective starters, SafePro B-SF-43 and SafePro B-LC-20, in a model simulating in vitro the first step of the fermentation process. The presence of the bioprotective starters did not modify the pH in such a way that could affect the safety or organoleptic properties of the product. Both SafePro B-SF-43 and SafePro B-LC-20 effected an important reduction of Listeria counts (0.56 and 0.72 log CFU g-1, respectively, in 72 h), while the anti-Listeria effect of L. delbrueckii WC0286 was minor (0.15 log CFU g-1). These results discouraged the utilization of L. delbrueckii WC0286 for a challenge test in a pilot salami production, in favor of the best-performing bioprotective starter, SafePro B-LC-20. The test confirmed that SafePro B-LC-20 did not alter the acidification trend of sausages and was capable of inhibiting Listeria, which decreased by 1.21 log CFU g-1. This information is relevant to address research activity toward the development of new bioprotective starters. The data herein presented demonstrate that the efficacy in Listeria control of potentially bioprotective bacterial starters requires further validation in real meat matrixes, possibly by using in vitro meat fermentation experiments to narrow down the list of candidates before pilot scale challenge tests. [ABSTRACT FROM AUTHOR]

Abstract: Imidazolium poly(butylene terephthalate) ionomers with ionic groups located randomly along the polymer chain or selectively as end-groups (telechelic) have been prepared in order to determine their antimicrobial (AM) activity. Two different approaches have been followed for the linkage of the imidazolium to the polymer backbone: a covalent bond and an ionic aggregation to sulfonated groups covalently bonded to the polymer. The ionic groups have been linked to the polymer in order to improve the long-term AM activity since the low molecular weight additives commonly used tends to migrate toward the surface during use. We have found that imidazolium ionomers present AM activity comparable with that of commercial antimicrobial agents such as Triclosan. The AM activity depends on the polymer architecture, the telechelic approach being more active compared to the random approach. We have proved that imidazolium ionomers retain their high AM activity even after 6 days in water at 60 °C while Triclosan consistently loses his activity. [Copyright &y& Elsevier]

Abstract: Surface coatings of pretreated poly(fluoroethylene propylene) (FEP) films by UV-induced graft copolymerization with 2-hydroxyethyl methacrylate (HEMA) and an antimicrobial agent, 3-hexadecyl-1-vinylimidazolium bromide (VIB), have been carried out. Surface chemical and morphological modifications were investigated with spectroscopic analysis using attenuated total reflectance Fourier transform infrared spectroscopy (ATR FT-IR), scanning electron microscopy (SEM) and X-ray diffraction distribution map of bromide atoms. Fluorescein dye absorption studies were performed in order to quantify the amount of reacted VIB. Antibacterial activities were assayed with Staphylococcus aureus (S. aureus, a Gram positive bacterium) culture on HEMA-VIB modified FEP specimens, prepared with different amounts of the antimicrobial agent. In addition to bactericidal properties, the functionalized FEP surface also prevented the adhesion of microorganisms to the film. [Copyright &y& Elsevier]

Abstract: Poly(butylene terephthalate) ionomers with imidazolium groups selectively located as end-groups (telechelic) have been prepared by melt polycondensation adding a hydroxyl derivatized imidazolium salt at the beginning of the polymerization process. The design of the chemical structure of the imidazolium salt is of fundamental importance in order to achieve the synthesis of ionomers with good thermo-mechanical properties. The final ionomers present high molecular weight, good color, transparency and thermal stability. Imidazolium ionomers present good antimicrobial (AM) properties comparable with those of commercial AM agents. The incorporation of the ionic groups in the polymer chain prevents their migration during use and therefore the antimicrobial activity can be preserved for longer time. [Copyright &y& Elsevier]

Abstract: Anatase-structured TiO2 films were deposited on a commercial fluorinated polymer (FEP) with a treated surface, by means of a sol–gel dip-coating technique. Two different curing temperatures were investigated and the film microstructures were characterized by X-ray diffraction, atomic force microscopy and scanning electron microscopy analyses. The prepared samples presented very high performances in terms of photocatalytic activities, analyzed by the degradation of an organic dye in a liquid medium, and of bactericidal activities, tested on Staphylococcus aureus (S. aureus, a Gram positive bacterium) and Escherichia coli (E. coli, a Gram negative bacterium). [Copyright &y& Elsevier]

Abstract: Wastewater from textile industry usually undergoes activated sludge biotreatment ahead of refining treatments, final discharge or reuse. To identify the most effective bioreactor typology for the secondary treatment of a wastewater resulting from a textile industry of the Biella district (Italy), four pilot units characterized by a different configuration and fluid dynamics (i.e., Bioflotation®, Fixed Bed Biofilm Reactor (FBBR), flow-jet aeration and standard aerobic sludge reactors) were operated in parallel, inoculated with the same microbial consortium and fed with identical streams of wastewater discharged from wet textile processes of the industy. COD, TC and non-ionic surfactants were monitored in effluents of the compared bioreactors working under continuous mode and the cultivable heterotrophic microorganisms prevailing in each of them were isolated and characterized as the end of the study. The results demonstrated that the air supply system greatly influenced the treatment efficiency which reached the highest value in the case of Bioflotation® and FBBR technology. A highly specialized bacterial biomass mostly composed by strains of the Pseudomonas, Stenotrophomonas and Ochrobactrum genera was isolated in such reactors, thus suggesting that a direct correlation between reactor configuration, decontamination performances and microbial biomass composition exist. [Copyright &y& Elsevier]

• 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]

Abstract: Campylobacteriosis is at present the most frequent zoonosis in humans and the main source is poultry meat contaminated by Campylobacter jejuni. An alternative and effective approach to antibiotic administration to livestock to reduce bacterial contamination is the use of probiotics, which can help to improve the natural defence of animals against pathogenic bacteria. In this study 55 lactic acid bacteria and bifidobacteria were screened for desirable properties for their application as probiotics against Campylobacter in poultry. All bacteria were examined for their antimicrobial activity against three C. jejuni strains. Strains exhibiting the highest anti-Campylobacter activity were examined for their survival in the gastro intestinal tract (low pH and presence of bile salts) and food/feed processing conditions (high temperature, high NaCl concentration and starvation) and basic safety aspects such as antibiotic susceptibility and hemolytic activity were studied. On the basis of these activities, two strains, namely Lactobacillus plantarum PCS 20 and Bifidobacterium longum PCB 133, were chosen for an in vivo trial in poultry. They were separately administered to healthy chickens in order to evaluate their capability of colonizing the GI tract of poultry and to estimate their effect on C. jejuni population. The results evidenced that L. plantarum PCS 20 was not present in poultry feces at detectable concentration, whereas B. longum PCB 133 significantly increased after two weeks of daily administration and its amount was still high after a wash-out period of 6days. In the same period, C. jejuni concentration in poultry feces was significantly reduced in chickens administered with B. longum PCB 133. Therefore, B. longum PCB 133, possessing interesting probiotic properties and a marked anti-Campylobacter activity both in vitro and in vivo, is an excellent candidate for being employed as additives to feed for poultry for the reduction of food-borne campylobacteriosis in humans. [Copyright &y& Elsevier]