Campylobacter californiensis sp. nov., isolated from cattle and feral swine.

Nine Campylobacter strains were isolated from cattle and feral swine faeces: three were recovered during a 2007 Campylobacter-associated outbreak linked to a dairy, and the other six were isolated during a 2009-2010 survey of farms and ranches in Central California. The species identification of these strains could not be determined by 16S rRNA gene sequencing but were most similar to Campylobacter concisus and Campylobacter mucosalis. Additional atpA typing indicated that the nine strains composed a discrete novel clade related to C. concisus and C. mucosalis. A polyphasic study was undertaken here to clarify their taxonomic position. Phylogenetic analyses were performed based on 16S rRNA gene sequences and the concatenated sequences of 330 core genes. The core gene analysis placed the nine strains into a clade well separated from the other Campylobacter taxa, indicating that these strains represent a novel Campylobacter species. Pairwise digital DNA-DNA hybridization and average nucleotide identity values between these strains and other campylobacters are lower than 16 and 73%, respectively, further supporting their placement into a novel taxon. Standard phenotypic testing was performed. All strains are microaerobic or anaerobic, motile, Gram-negative, slightly-curved rods that are oxidase positive but catalase negative. Strains can be distinguished from the other catalase-negative Campylobacter species using phenotypic markers such as motility, oxidase activity, cephalothin resistance, hippuricase activity, growth at 30 °C, and α-haemolysis. The data presented here show that these strains represent a novel species within Campylobacter, for which the name Campylobacter californiensis sp. nov. (type strain RM6914T=LMG 32304T=CCUG 75329T) is proposed.

Campylobacter devanensis sp. nov., Campylobacter porcelli sp. nov., and Campylobacter vicugnae sp. nov., three novel Campylobacter lanienae-like species recovered from swine, small ruminants, and camelids.

In a previous study characterizing Campylobacter strains deficient in selenium metabolism, 50 strains were found to be similar to, but distinct from, the selenonegative species Campylobacter lanienae. Initial characterization based on multilocus sequence typing and the phylogeny of a set of 20 core genes determined that these strains form three putative taxa within the selenonegative cluster. A polyphasic study was undertaken here to further clarify their taxonomic position within the genus. The 50 selenonegative strains underwent phylogenetic analyses based on the sequences of the 16S rRNA gene and an expanded set of 330 core genes. Standard phenotypic testing was also performed. All strains were microaerobic and anaerobic, Gram-negative, spiral or curved cells with some displaying coccoid morphologies. Strains were motile, oxidase, catalase, and alkaline phosphatase positive, urease negative, and reduced nitrate. Strains within each clade had unique phenotypic profiles that distinguished them from other members of the genus. Core genome phylogeny clearly placed the 50 strains into three clades. Pairwise average nucleotide identity and digital DNA-DNA hybridization values were all below the recommended cut-offs for species delineation with respect to C. lanienae and other related Campylobacter species. The data presented here clearly show that these strains represent three novel species within the genus, for which the names Campylobacter devanensis sp. nov. (type strain RM3662T=LMG 33097T=NCTC 15074T), Campylobacter porcelli sp. nov. (type strain RM6137T=LMG 33098T=CCUG 77054T=NCTC 15075T) and Campylobacter vicugnae sp. nov. (type strain RM12175T=LMG 33099T=CCUG 77055T=NCTC 15076T) are proposed.

Potential of NIR spectroscopy for predicting cellulose nanofibril quality in commercial bleached Kraft pulp of Eucalyptus.

Multivariate models were developed to classify cellulose nanofibril (CNF) fibrillation by a quality index from near infrared (NIR) spectra. Commercial pulps of Eucalyptus spp. were used to produce cellulose nanofibrils by means of a fibrillator mill. After each of the five passes through the mill, samples were collected and analyzed for energy consumption and fiber classification. As a standard, pulps were oxidized with TEMPO reagent followed by a single pass through the mill to compare the resulting quality of CNFs produced by each method. NIR spectra of CNFs were associated with quality indices determined by conventional laboratory analyses that included morphology, turbidity, mechanical properties, X-ray diffraction and quality index measurements. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were applied to the spectral and experimental data. Fibrillator milling to obtain CNFs was efficient and resulted in gel formation following the third pass through the mill. NIR spectroscopy combined with PLS-DA was used successfully to create a model to classify quality of CNFs with 96 % certainty in 3 wt% solutions. These findings suggest that NIR spectroscopy holds promise for estimating CNF quality in suspension, particularly in real-time industrial applications where reliable estimates are crucial.

Novel isochoric impregnation to develop high-quality and nutritionally fortified plant materials (apples and sweet potatoes).

Isochoric impregnation was explored as a novel pressure-assisted infusion technique to fortify plant materials with bioactive compounds. Apple and potato cylinders were impregnated with a sucrose solution containing 4% ascorbic acid (AA) while freezing under isochoric conditions. Isochoric impregnation resulted in greater infusion of AA compared to infusion at atmospheric pressure, which demonstrated the feasibility of this impregnation technology. Processing temperatures (-3°C and -5°C) and processing times (1, 3, and 5 h) significantly affected the AA infusion. The AA content values ranged from 446 to 516 mg/100 g for apples and 322 to 831 mg/100 g for sweet potatoes under isochoric conditions. For both plant materials, isochoric impregnation at -3°C did not cause major changes in texture and microstructure of the biological tissues. These results indicated that isochoric impregnation of solid foods could be a feasible technology for infusion of bioactive compounds without significantly altering their matrix. PRACTICAL APPLICATION: The findings of this study showed that the use of isochoric impregnation as a fortification technique is a promising way to develop fresh-like and value-added products with improved nutrition during preservation at subfreezing temperatures.

Polyhydroxybutyrate Rice Hull and Torrefied Rice Hull Biocomposites.

Raw and torrefied rice hulls (RRH and TRH) were incorporated into polyhydroxybutyrate (PHB) as fillers using extrusion and injection molding to produce biomass-polymer composites. Filler and composite materials were characterized by particle size analysis, thermomechanical analysis, thermogravimetric analysis, differential scanning calorimetry, FTIR analysis, CHNSO analysis, and mechanical testing. Heat distortion temperature of the RRH composites were 16-22 °C higher than TRH composites. The RRH composite samples showed a 50-60% increase in flexural modulus and 5% increase in stress at yield compared to PHB, while TRH composite samples showed nearly equal flexural modulus and a 24% decrease in stress at yield. The improved mechanical properties of the RRH composites in comparison to TRH composites were due to better particle-matrix adhesion. FTIR analysis showed RRH particles contained more surface functional groups containing oxygen than TRH particles, indicating that RRHs should be more compatible with the polar PHB plastic. SEM images showed space between filler and plastic in TRH composites and better wetted filler particles in the RRH composites.

Preservation of grape tomato by isochoric freezing.

This study investigated the potential of isochoric freezing to preserve tomatoes. Isochoric freezing is an emerging technology that preserves biological matter at subfreezing temperatures without any ice damage. Isochoric freezing was compared with freezing under isobaric conditions and with preservation techniques used in the food industry: cold storage at 10 °C and individual quick freezing (IQF). Physicochemical and nutritional properties were evaluated weekly for four weeks. Preservation under isochoric conditions maintained the mass, color, nutrient content (ascorbic acid, lycopene and phenolics) and antioxidant activity of the fresh tomatoes. Also, isochoric preservation led to minimal texture damage. In comparison, mass loss of tomatoes stored at 10 °C for 3 weeks contributed to changes in overall visual quality and firmness as well as significant losses in nutrient content. The greatest mass, texture, and nutrients losses were obtained for tomatoes subjected to IQF and isobaric freezing. The results show that isochoric freezing has the potential to preserve tomatoes while maintaining physicochemical and nutritional properties similar to those of fresh tomatoes which might find application in the commercial preservation of tomatoes.

Effect of Cross-Linked Alginate/Oil Nanoemulsion Coating on Cracking and Quality Parameters of Sweet Cherries.

The cracking of sweet cherries causes significant crop losses. Sweet cherries (cv. Bing) were coated by electro-spraying with an edible nanoemulsion (NE) of alginate and soybean oil with or without a CaCl2 cross-linker to reduce cracking. Coated sweet cherries were stored at 4 °C for 28 d. The barrier and fruit quality properties and nutritional values of the coated cherries were evaluated and compared with those of uncoated sweet cherries. Sweet cherries coated with NE + CaCl2 increased cracking tolerance by 53% and increased firmness. However, coated sweet cherries exhibited a 10% increase in water loss after 28 d due to decreased resistance to water vapor transfer. Coated sweet cherries showed a higher soluble solid content, titratable acidity, antioxidant capacity, and total soluble phenolic content compared with uncoated sweet cherries. Therefore, the use of the NE + CaCl2 coating on sweet cherries can help reduce cracking and maintain their postharvest quality.

Redispersion and structural change evaluation of dried microfibrillated cellulose.

Commercializing dried microfibrillated cellulose (MFC) has always been a challenge mainly due to the tendency of MFC to aggregate. In this study MFC samples were submitted to drying/redispersion cycles at different temperatures. Morphology, crystallinity and mechanical performance of films were analyzed throughout the cycles. Microscopy images, particle size and stability in water showed that aggregation happens more severely with 5 drying/redispersion cycles and at drying temperatures of 75 and 100 °C. Particles once-dried at 20 °C formed the same size and web-like structure as the MFC-control. Crystallinity and crystallite sizes increased with drying/redispersion cycles especially when dried at 75 and 100 °C, however drying/redispersion cycles also led to a reduction in mechanical performance due to aggregation. While oven-drying is not the most suitable method, milder action at room temperature once-drying led to suspension stability in water, morphology and mechanical properties close to never-dried MFC, which makes this treatment a feasible option to maintain cellulose quality.

Environmentally responsive QTL controlling surface wax load in switchgrass.

KEY MESSAGE: Quantitation of leaf surface wax on a population of switchgrass identified three significant QTL present across six environments that contribute to leaf glaucousness and wax composition and that show complex genetic × environmental (G × E) interactions. The C4 perennial grass Panicum virgatum (switchgrass) is a native species of the North American tallgrass prairie. This adaptable plant can be grown on marginal lands and is useful for soil and water conservation, biomass production, and as a forage. Two major switchgrass ecotypes, lowland and upland, differ in a range of desirable traits, and the responsible underlying loci can be localized efficiently in a pseudotestcross design. An outbred four-way cross (4WCR) mapping population of 750 F2 lines was used to examine the genetic basis of differences in leaf surface wax load between two lowland (AP13 and WBC) and two upland (DAC and VS16) tetraploid cultivars. The objective of our experiments was to identify wax compositional variation among the population founders and to map underlying loci responsible for surface wax variation across environments. GCMS analyses of surface wax extracted from 4WCR F0 founders and F1 hybrids reveal higher levels of wax in lowland genotypes and show quantitative differences of ß-diketones, primary alcohols, and other wax constituents. The full mapping population was sampled over two seasons from four field sites with latitudes ranging from 30 to 42 °N, and leaf surface wax was measured. We identified three high-confidence QTL, of which two displayed significant G × E effects. Over 50 candidate genes underlying the QTL regions showed similarity to genes in either Arabidopsis or barley known to function in wax synthesis, modification, regulation, and transport.

Effect of isochoric freezing on quality aspects of minimally processed potatoes.

The enhanced interest in greater convenience foods has recently led to the expansion of minimally processed potato products. This study investigated the effects of isochoric freezing on pre-peeled potato cubes, including quality attributes (microstructure, texture, and color), nutritional value (ascorbic acid (AA) content, total phenolic content, and antioxidant capacity), and polyphenol oxidase activity. Isochoric freezing (-3 °C/30 MPa) was compared with isobaric freezing (-3 °C/0.1 MPa) and individual quick freezing followed by frozen storage at -20 °C for 4 weeks. The isochoric sample had lower drip loss and volume shrinkage as well as better preserved texture and microstructure than the other samples. All freezing methods caused an increase in total phenolic content and antioxidant capacity, but a decrease in AA content. Also, all freezing methods caused browning of the thawed potatoes, but isochoric freezing delayed its onset for more than 1 week. PRACTICAL APPLICATION: Results showed that isochoric freezing of pre-peeled and cut potatoes caused less freeze damage than isobaric and individual quick freezing, which might find application in the commercial preservation of minimally processed food products.

Massaranduba Sawdust: A Potential Source of Charcoal and Activated Carbon.

This paper provides proof of concept that activated carbon (AC) may be readily produced using limited conversion methods and resources from sawdust of massaranduba (Manilkara huberi) wood, thereby obtaining value-added products. Sawdust was sieved and heat-treated in an oxygen-free muffle furnace at 500 °C to produce charcoal. The charcoal was activated in a tubular electric furnace at 850 °C while being purged with CO2 gas. Microstructural, thermal and physical properties of the three components: sawdust, charcoal and AC were compared by means of field emission scanning electron microscopy (FESEM), X-ray diffractometry (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), density and water adsorption/desorption measurements. The resulting AC had a large surface area as measured by Brunauer-Emmett-Teller (BET) comparable to other such values found in the literature. The large surface area was due to pore development at the microstructural level as shown by FESEM. XRD illustrated that sawdust had a semi-crystalline structure whereas charcoal and AC evidenced mostly amorphous structures. TGA and DSC showed that AC had high reactivity to moisture compared to sawdust and charcoal.

Disrupted breath, songlines of breathlessness: an interdisciplinary response.

Health research is often bounded by disciplinary expertise. While cross-disciplinary collaborations are often forged, the analysis of data which draws on more than one discipline at the same time is underexplored. Life of Breath, a 5-year project funded by the Wellcome Trust to understand the clinical, historical and cultural phenomenology of the breath and breathlessness, brings together an interdisciplinary team, including medical humanities scholars, respiratory clinicians, medical anthropologists, medical historians, cultural theorists, artists and philosophers. While individual members of the Life of Breath team come together to share ongoing work, collaborate and learn from each other's approach, we also had the ambition to explore the feasibility of integrating our approaches in a shared response to the same piece of textual data. In this article, we present our pluralistic, interdisciplinary analysis of an excerpt from a single cognitive interview transcript with a patient with chronic obstructive pulmonary disease. We discuss the variation in the responses and interpretations of the data, why research into breathlessness may particularly benefit from an interdisciplinary approach, and the wider implications of the findings for interdisciplinary research within health and medicine.

Bio-based thin films of cellulose nanofibrils and magnetite for potential application in green electronics.

The objective of this work was to prepare bio-based thin films and evaluate the additions of magnetite and glycerol on the physico-chemical (flexibility, wettability and barrier properties) and dielectric properties of cellulose/chitosan-based films. The films were prepared by solution casting and presented a suitable dispersion of the constituents observed by SEM and FTIR. The films were thermally stable up to 150 °C and had a higher flexibility, wettability and lower barrier properties upon addition of glycerol. The calculated dielectric constant (εr) for the composite films was based on measurements of capacitance, at 100 and 1000 Hz, with the additions of magnetite and glycerol more than doubling the εr increasing the charge storage capacity. The bio-based thin films have potential to be used as insulators in capacitors on the production of green electronics thus, reducing toxic and nonrenewable e-waste generation.

Layer-by-Layer Alginate and Fungal Chitosan Based Edible Coatings Applied to Fruit Bars.

Food waste is currently being generated at an increasing rate. One proposed solution would be to convert it to biopolymers for industrial applications. We recovered chitin from mushroom waste and converted it to chitosan to produce edible coatings. We then used layer-by-layer (LbL) electrostatic deposition of the polycation chitosan and the polyanion alginate to coat fruit bars enriched with ascorbic acid. The performance of the LbL coatings was compared with those containing single layers of fungal chitosan, animal origin chitosan and alginate. Bars containing alginate-chitosan LbL coatings showed increased ascorbic acid content, antioxidant capacity, firmness and fungal growth prevention during storage. Also, the origin of the chitosan did not affect the properties of the coatings. PRACTICAL APPLICATION: Mushroom stalk bases could be an alternative source for isolating chitosan with similar properties to animal-based chitosan. Also, layer-by-layer assembly is a cheap, simple method that can improve the quality and safety of fruit bars.

Solution blow spun nanocomposites of poly(lactic acid)/cellulose nanocrystals from Eucalyptus kraft pulp.

Cellulose nanocrystals (CNCs) were extracted from Eucalyptus kraft pulp by sulfuric acid hydrolysis, and esterified with maleic anhydride (CNCMA). The incorporation of sulfate ester groups on the cellulose surface resulted in higher stability of the nanoparticles in aqueous suspensions and lower thermal stability. Then, PLA/CNC and PLA/CNCMA nanocomposites were successfully obtained by solution blow spinning (SBS) using dimethyl carbonate (DMC) as solvent. CNC and CNCMA indicated to be acting both as nucleating agents or growth inhibitors of PLA crystal and tends to favor the formation of PLA crystals of higher stability. A fraction of the nanocrystals indicate to be exposed on the surface of the PLA fibers, since the hydrophilicity of the composite films increased significantly. Such composites may have potential application as filtering membranes or adsorbents.

Solution Blow Spinning of Food-Grade Gelatin Nanofibers.

The primary advantage of nanofibers over larger diameter fibers is the larger surface area to volume ratio. This study evaluated solution blow spinning (SBS) processing conditions for obtaining food-grade gelatin nanofibers from mammalian and fishery byproducts, such as pork skin gelatins (PGs) and high molecular weight fish skin gelatin (HMWFG). HMWFG had a highest intact collagen structure compared to PGs. PGs with different Bloom values, solution viscosities, and surface tensions were compared with HMWFG for their ability to produce nanofibers through SBS. Only HMWFG fibers were obtained irrespective of processing conditions, which looked like fluffy cotton candy. HMWFG nanofibers had round morphologies with a narrower diameter distribution and lower average fiber diameter (AFD) under medium gelatin concentrations, medium air pressures, and medium feed rates. The highest glass transition temperature (Tg ) values were obtained at medium concentrations, medium air pressure, and either high or low feed rate. The thinnest HMWFG nanofibers with an AFD of 80.1 nm and the highest Tg value of 59.0 °C could be formed by combining a concentration of 17.6% (w/v), an air pressure of 0.379 MPa, and a feed rate of 0.06 mL/min from the response surface analysis. HMWFG Brunauer, Emmett, and Teller surface area increased from 221 to 237 m2 /g, indicating their potential applicability for active compound carrier.

Sequencing and functional validation of the JGI Brachypodium distachyon T-DNA collection.

Due to a large and growing collection of genomic and experimental resources, Brachypodium distachyon has emerged as a powerful experimental model for the grasses. To add to these resources we sequenced 21 165 T-DNA lines, 15 569 of which were produced in this study. This increased the number of unique insertion sites in the T-DNA collection by 21 078, bringing the overall total to 26 112. Thirty-seven per cent (9754) of these insertion sites are within genes (including untranslated regions and introns) and 28% (7217) are within 500 bp of a gene. Approximately 31% of the genes in the v.2.1 annotation have been tagged in this population. To demonstrate the utility of this collection, we phenotypically characterized six T-DNA lines with insertions in genes previously shown in other systems to be involved in cellulose biosynthesis, hemicellulose biosynthesis, secondary cell wall development, DNA damage repair, wax biosynthesis and chloroplast synthesis. In all cases, the phenotypes observed supported previous studies, demonstrating the utility of this collection for plant functional genomics. The Brachypodium T-DNA collection can be accessed at http://jgi.doe.gov/our-science/science-programs/plant-genomics/brachypodium/brachypodium-t-dna-collection/.

Vitamin D-fortified chitosan films from mushroom waste.

Brown mushroom (Agaricus bisporus) stalk bases from mushroom waste were treated with UV-B light to rapidly increase vitamin D2 content. Chitin was also recovered from this waste and converted into chitosan by N-deacetylation. FTIR spectra showed that the mushroom chitosan were similar to chitosan from animal sources. Chitosan films were prepared using high molecular weight (HW), low molecular weight (LW) and fungal chitosan. UV-B treated mushroom particles were also incorporated into fungal chitosan films. The fungal chitosan films showed similar density, porosity and water vapor barrier properties to the LW and HW chitosan films. However, fungal chitosan films were more hydrophobic and less flexible than the LW and HW chitosan films. Addition of mushroom particles did not significantly affect mechanical or water barrier properties of the fungal chitosan films.

Renewable hybrid nanocatalyst from magnetite and cellulose for treatment of textile effluents.

A hybrid catalyst was prepared using cellulose nanofibrils and magnetite to degrade organic compounds. Cellulose nanofibrils were isolated by mechanical defibrillation producing a suspension used as a matrix for magnetite particles. The solution of nanofibrils and magnetite was dried and milled resulting in a catalyst with a 1:1 ratio of cellulose and magnetite that was chemically and physically characterized using light, scanning electron and transmission electron microscopies, specific surface area analysis, vibrating sample magnetometry, thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction, catalytic potential and degradation kinetics. Results showed good dispersion of the active phase, magnetite, in the mat of cellulosic nanofibrils. Leaching and re-use tests showed that catalytic activity was not lost over several cycles. The hybrid material produced was tested for degradation of methylene blue dye in Fenton-like reactions resulting in a potential catalyst for use in degradation of organic compounds.

Preparation of Zein Fibers Using Solution Blow Spinning Method.

Zein fibers were successfully fabricated via solution blow spinning (SBS) using acetic acid as solvent. Surface tension, viscosity and modulus of zein solutions were respectively determined by force tensiometer and rheometer. Increases of these properties were observed with an increase of concentration from 20% to 35% (w/w). The fabrication conditions of zein fibers were initially investigated as a function of zein concentration (25% to 35% w/w), feed rate (0.04 to 0.1 mL/min) and air pressure (0.28 to 0.62 MPa). The average fiber diameter (AFD) ranged from 174 to 9595 nm based on scanning electron microscopy (SEM). A Box-Behnken experimental design (BBD) was further performed to identify and quantify the significance of above parameters. The statistical analysis showed that the linear coefficient of concentration, the quadratic term of concentration as well as the interaction between concentration and air pressure were demonstrated statistically significant. Optimal conditions, with an AFD of 138 nm, could be obtained in the SBS of zein fibers by combining a concentration of 23% (w/w), a feed rate of 0.04 mL/min and an air pressure of 0.38 MPa. The moisture sorption capacity of fibers increased slightly as AFD decreased from ∼550 to ∼200 nm, with an increase of BET surface area from 116.5 to 140.0 m2 /g.