Digestibility of common native starches with reference to starch granule size,shape and surface features towards guidelines for starch-containing food products

Influence of diverse botanical sources (wheat, maize, waxy maize, cassava, potato, rice or waxy rice) on in vitro native starch digestibility has been investigated. Physicochemical properties (chemical composition, particles size and shape, surface features) of starch granules were determined with a view to explaining digestibility differences between samples. Rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) contents were measured according to Englyst method. Potato starch was shown to be composed of large rounded granules having smooth surfaces, which explains its slow enzymatic breakdown. Potato starch displayed the highest RS (86%) content and the lowest RDS content (9.9%). Since RS positively influences health and SDS may result in cell, tissue and/or organ damages, potato starch is an ideal starch nutrient. Conversely, waxy rice starch was rich in amylopectin and displayed small diameters and angular shapes, which are both known to facilitate enzymatic starch hydrolysis. It exhibited a near-zero RS content (0.9%) and a high RDS fraction (60%). According to this study, potato starch exhibited the best nutrient profile, followed up in this order by cassava, waxy maize, wheat, maize and waxy rice starches.     

Antimicrobial properties of 1‐monoacylglycerols prepared from undecanoic (C11:0) and undecenoic (C11:1) acid

Antimicrobial activity of monoacylglycerols (MAG) with odd number of carbons prepared from undecanoic (MAG C11:0) and undecenoic (MAG C11:1) was investigated. Data showed that both studied substances successfully inhibited Gram‐positive cocci (Staphylococcus aureus) and spore‐forming rods (Bacillus cereus). Gram‐negative bacteria were highly resistant against MAG C11:0 and showed considerable tolerance against MAG C11:1. Minimum inhibitory concentration (MIC) of MAG C11:1 was possible to determine for Escherichia coli only. Complete inhibition of three fungi genera (Alternaria, Cladosporium, Trichothecium) was achieved using MAG C11:1 with a concentration higher than 750 µg/mL. The growth of Aspergillus niger, Mucor racemosus, Phoma, Scopulariopsis, Trichoderma was significantly reduced. Generally, MAG C11:1 was more efficient than MAG C11:0 against all tested microorganisms. Due to a rich production of degradation enzymes, some fungi species surprisingly adapted their metabolism during growth and were even able to utilise tested MAG as a source of carbon. Practical applications: MAG composed of fatty acids with odd number of carbons in molecule are a promising group of substances applicable in food industry and cosmetics. They represent materials with broad spectrum of antimicrobial activity, especially against Gram‐positive bacteria. More efficient MAG C11:1 with a double bond in molecule can be recommended for reduction of S. aureus that cause food enterotoxicosis.     

Aerosol Synthesis and Characterization of Ultrafine Fullerene Particles

Abstract

Aerosol routes were used to produce fullerene particles in the nanometer size range. Particle formation mechanisms at processing temperatures of 400-700°C were studied by measuring particle number and mass size distributions in the gas phase by a differential mobility analyzer and a low-pressure impactor respectively. Subsequently, the foils of the impactor onto which fullerene particles were collected were examined by HPLC.     

Advanced performance evaluation of a reverse osmosis treatment for oilfield produced water aiming reuse

Technology advancements and the increasing need for fresh water resources have created the potential for desalination of oil field brine (produced water) to be a cost-effective fresh water resource for beneficial reuse. At the mature oil and gas production areas in the northeast of Brazil, the majority of wells produce a substantial amount of water in comparison with oil production (more than 90%). At these fields, the produced water has to be treated on site only for oil and solids removal aiming re-injection. The aim of this work is to assess the quality of the produced water stream after a reverse osmosis desalination process in terms of physicochemical characteristics influencing reuse of the water for irrigation or other beneficial uses.     

Systematic organophilization of montmorillonite: The impact thereof on the rheometric and mechanical characteristics of NBR and SBR based nanocomposites

Different montmorillonites either, completely hydrophilic (Mont‐0), amphiphilic (Mont‐25, Mont‐50, and Mont‐75) or completely hydrophobic (Mont‐100) were used as reinforcing fillers for styrene butadiene rubber (SBR) and acrylonitrile butadiene rubber (NBR) individually to predict the influence of the different forms on the properties of the rubbers (rheometric characteristics and mechanical properties). The shifts in the glass transition temperatures after the clay insertion were determined from dynamic mechanical thermal analysis to investigate the preference and action of each form. In addition, the storage moduli were used as indications to the corresponding mechanical properties of the samples. The influences could be followed after comparing the impacts of aging conditions on the properties of rubber compositions. The obtained data may provide a platform to suggest the mechanism by which these forms can in some cases act as compatibilizers in addition to their reinforcing/plasticizing effect when employed with the physically incompatible NBR/SBR (50/50) blend, which helps to optimize the properties of nanocomposites based on these blends. The proposed mechanism of action showed good correlation with the results of the mechanical properties and x‐ray diffraction investigations as well. POLYM. ENG. SCI., 54:942–948, 2014. © 2013 Society of Plastics Engineers     

Chemical characterisation of marine aerosol at Amsterdam Island during the austral summer of 2006–2007

Atmospheric aerosols were collected in separate fine (<2.5 μm) and coarse (>2.5 μm) size fractions in the period December 2006–March 2007 at Amsterdam Island in the southern Indian Ocean. A major objective of the study was to assess biogenic impact on the marine aerosol. The samples were analysed for organic carbon, water-soluble organic carbon, major inorganic ionic species, and organic species, including methanesulphonate (MSA), dicarboxylic acids, and organosulphates. The concentrations of sea salt, non-sea-salt sulphate, and water-soluble and water-insoluble organic matter (WSOM and WIOM) were estimated. Sea salt dominated the composition of the aerosol and accounted for 83% and 91% of the sum of the mass of the four aerosol types in the fine and coarse size fractions, respectively. WSOM, which can serve as a proxy for biogenic secondary organic aerosol (SOA), accounted for only 2.8% of the sum of the mass of the four aerosol types in the fine size fraction. MSA was the dominating organic compound with a median concentration of 47 ng m^?3. The organosulphates were characterised as sulphate esters of hydroxyl acids and a dihydroxylaldehyde, which may originate from the oxidation of algal/bacterial unsaturated fatty acid residues. No evidence was found for isoprene SOA.     

Consumers’ quality perception of national branded, national store branded, and imported store branded beef

This study investigated the differences in the consumers’ quality perception of national branded, national store branded, and imported store branded beef. Partial Least Squares analysis is used for modelling the quality perception process. Results show that consumers perceived national branded Carnalentejana beef, as better on all quality cues and quality aspects than the other two store branded beefs. Preference for Carnalentejana beef stayed highly consistent even after the blind test, where consumers differentiated this beef from the other two beef brands on all sensory dimensions: taste, tenderness, and juiciness, and chose it as the preferred one. Consumers utilized more perceived intrinsic cues to infer expected eating quality of store branded beefs.     

Zebrafish as a Model for the Study of Lipid-Lowering Drug-Induced Myopathies

Drug-induced myopathies are classified as acquired myopathies caused by exogenous factors. These pathological conditions develop in patients without muscle disease and are triggered by a variety of medicaments, including lipid-lowering drugs (LLDs) such as statins, fibrates, and ezetimibe. Here we summarise the current knowledge gained via studies conducted using various models, such as cell lines and mammalian models, and compare them with the results obtained in zebrafish (Danio rerio) studies. Zebrafish have proven to be an excellent research tool for studying dyslipidaemias as a model of these pathological conditions. This system enables in-vivo characterization of drug and gene candidates to further the understanding of disease aetiology and develop new therapeutic strategies. Our review also considers important environmental issues arising from the indiscriminate use of LLDs worldwide. The widespread use and importance of drugs such as statins and fibrates justify the need for the meticulous study of their mechanism of action and the side effects they cause.     

Ramp‐Reversal Memory and Phase‐Boundary Scarring in Transition Metal Oxides

Transition metal oxides are complex electronic systems that exhibit a multitude of collective phenomena. Two archetypal examples are VO₂ and NdNiO₃, which undergo a metal–insulator phase transition (MIT), the origin of which is still under debate. Here this study reports the discovery of a memory effect in both systems, manifested through an increase of resistance at a specific temperature, which is set by reversing the temperature ramp from heating to cooling during the MIT. The characteristics of this ramp‐reversal memory effect do not coincide with any previously reported history or memory effects in manganites, electron‐glass or magnetic systems. From a broad range of experimental features, supported by theoretical modelling, it is found that the main ingredients for the effect to arise are the spatial phase separation of metallic and insulating regions during the MIT and the coupling of lattice strain to the local transition temperature of the phase transition. We conclude that the emergent memory effect originates from phase boundaries at the reversal temperature leaving “scars” in the underlying lattice structure, giving rise to a local increase in the transition temperature. The universality and robustness of the effect shed new light on the MIT in complex oxides.