Some functional properties of lupin proteins modified by lactic fermentation and extrusion

The aim of this work was to determine modifying effects of lactic fermentation and extrusion processes on functionality of lupin proteins. Protein content, surface hydrophobicity, water absorption capacity (WAC), water solubility index (WSI) and emulsifying properties (EAI, ESI) of protein preparations obtained from lupin seeds (Lupinus luteus, Lupinus albus, Lupinus angustifolius), with various contents of hull, were analyzed. Changes of protein properties were affected by lupin cultivar, hull content and applied processing method. An increase of soluble protein content after controlled lactic fermentation of lupin seeds, and changes of surface protein hydrophobicity, WAC and WSI values after each treatment and significant worsening of protein emulsifying properties were observed. Correlations were found between parameters examined in this study.     

Comparison of antimicrobial resistance of Campylobacter jejuni and Campylobacter coli isolated from humans and chicken carcasses in Poland

Campylobacter-associated gastroenteritis remains an important cause of morbidity worldwide, and some evidence suggests that poultry is an important source of this foodborne infection in humans. This study was conducted to analyze the prevalence and genetic background of resistance of 149 Campylobacter jejuni and 54 Campylobacter coli strains isolated from broiler chicken carcasses and from stool samples of infected children in Poland from 2003 through 2005. Nearly all isolates were susceptible to macrolides and aminoglycosides. The highest resistance in both human and chicken strains was observed for ciprofloxacin (more than 40%), followed by ampicillin (13 to 21%), and tetracycline (8 to 29%). Resistance to ampicillin and tetracycline rose significantly between 2003 and 2005. Slight differences in resistance between human and chicken isolates indicate that although chicken meat is not the only source of Campylobacter infection in our population, it can be involved in the transmission of drug-resistant Campylobacter strains to humans.     

Computer rendering and visual detection of orange peel

The computer graphic simulation of a common spray painting artifact, called orange peel, is discussed. Orange peel distorts surface reflections and is commonplace in product design applications. The orange peel measurements from a standard industrial instrument are used to construct a height field, and this surface is rendered using traditional normal mapping techniques. Comparisons are made between real panels with orange peel and simulations of those panels. A simple visual model for detecting the presence of orange peel is also presented and evaluated. User testing of the model confirms that orange peel is more visible on dark paint colors than on light paint colors. The latter outcome suggests that to minimize application time, but still keep orange peel below visual threshold, paint application systems should be designed to take paint color into account.     

Finite element analysis of the effect of blanked edge quality upon stretch flanging of AHSS

Elimination of edge cracking is one of the major challenges in flanging of advanced high-strength steels (AHSS). Several studies show that edge cracking occurs at lower strains than those predicted by the forming limit curves (FLC) and it is influenced significantly by the sheared or blanked edge quality. This study focuses on FEM modeling and experiments on blanking and hole expansion of AHSS DP590. The FEM model of blanking was developed to characterize the edge quality for different punch/die clearances. Hole expansion was simulated to demonstrate the effect of sheared edge upon stretchability. Thus, it was possible to demonstrate how metal flow, strains and stresses in blanking affect the part quality and potential edge cracking in stretch flanging.     

Catalyst development for thermocatalytic decomposition of methane to hydrogen

The paper presents the results of the investigation into the development of a robust catalyst for hydrogen production by thermocatalytic decomposition (TCD) of methane. In this paper, we present the results of the development and utilization of an iron-based catalyst for TCD. The effect of catalyst preparation methodology on the activity and robustness of the catalysts is reported. The catalyst was synthesized from magnetite by reduction in the presence of a reducing gas (methane or hydrogen) using a fixed-bed flow reactor at atmospheric pressures and temperatures ranging from 800 to 900 °C. Reduction under methane was found to synthesize a catalyst with the desired properties and smallest preparation time (2 h). The main advantages of these catalysts identified were: their ability to completely decompose methane (as compared to a maximum of 81% by other catalysts) and to maintain high reactivity for a long period of time (more than 75 h). The catalyst was characterized by SEM, TEM, BET, XRD and particle size analysis. TPR was employed to evaluate the activity of the catalysts, to investigate the various mechanisms of methane decomposition reaction for the catalysts and estimate the kinetic parameters by topochemical model postulated by Avrami–Erofeyev. The estimated kinetic parameters from the analysis of this data are presented. Carbon nanofibers were formed as a co-product of the methane decomposition reactions.     

Bio-based polyurethane films using white dextrins

Several new eco-friendly materials have the potential to replace conventional petroleum-derived materials and monomers. Among them are natural polysaccharides. The use of polysaccharides in polyurethane (PU) synthesis has not yet been studied extensively, even though as multihydroxyl compounds, they can easily serve as crosslinkers in PU synthesis. One naturally occurring (hyper-)branched polymer is amylopectin, a component of starch. In this work, we report the PU synthesis and film-forming capacity using the asymmetric cyclic aliphatic diisocyanate—isophorone diisocyanate (IPDI) with acetylated and pristine partially hydrolyzed amylopectin/white dextrin (AVEDEX W80) as a crosslinker. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47454.     

On the Dependence of Prion and Amyloid Structure on the Folding Environment

Currently available analyses of amyloid proteins reveal the necessity of the existence of radical structural changes in amyloid transformation processes. The analysis carried out in this paper based on the model called fuzzy oil drop (FOD) and its modified form (FOD-M) allows quantifying the role of the environment, particularly including the aquatic environment. The starting point and basis for the present presentation is the statement about the presence of two fundamentally different methods of organizing polypeptides into ordered conformations—globular proteins and amyloids. The present study shows the source of the differences between these two paths resulting from the specificity of the external force field coming from the environment, including the aquatic and hydrophobic one. The water environment expressed in the fuzzy oil drop model using the 3D Gauss function directs the folding process towards the construction of a micelle-like system with a hydrophobic core in the central part and the exposure of polarity on the surface. The hydrophobicity distribution of membrane proteins has the opposite characteristic: Exposure of hydrophobicity at the surface of the membrane protein with an often polar center (as in the case of ion channels) is expected. The structure of most proteins is influenced by a more or less modified force field generated by water through the appropriate presence of a non-polar (membrane-like) environment. The determination of the proportion of a factor different from polar water enables the assessment of the protein status by indicating factors favoring the structure it represents.     

Novel Cell Permeable Polymers of N-Substituted L-2,3-Diaminopropionic Acid (DAPEGs) and Cellular Consequences of Their Interactions with Nucleic Acids

The present study aimed to synthesize novel polycationic polymers composed of N-substituted L-2,3-diaminopropionic acid residues (DAPEGs) and investigate their cell permeability, cytotoxicity, and DNA-binding ability. The most efficient cell membrane-penetrating compounds (O2Oc-Dap(GO2)_n-O2Oc-NH₂, where n = 4, 6, and 8) showed dsDNA binding with a binding constant in the micromolar range (0.3, 3.4, and 0.19 µM, respectively) and were not cytotoxic to HB2 and MDA-MB-231 cells. Selected compounds used in the transfection of a GFP plasmid showed high transfection efficacy and minimal cytotoxicity. Their interaction with plasmid DNA and the increasing length of the main chain of tested compounds strongly influenced the organization and shape of the flower-like nanostructures formed, which were unique for 5/6-FAM-O2Oc-[Dap(GO2)]₈-O2Oc-NH₂ and typical for large proteins.     

Solubility and Aggregation of Selected Proteins Interpreted on the Basis of Hydrophobicity Distribution

Protein solubility is based on the compatibility of the specific protein surface with the polar aquatic environment. The exposure of polar residues to the protein surface promotes the protein’s solubility in the polar environment. The aquatic environment also influences the folding process by favoring the centralization of hydrophobic residues with the simultaneous exposure to polar residues. The degree of compatibility of the residue distribution, with the model of the concentration of hydrophobic residues in the center of the molecule, with the simultaneous exposure of polar residues is determined by the sequence of amino acids in the chain. The fuzzy oil drop model enables the quantification of the degree of compatibility of the hydrophobicity distribution observed in the protein to a form fully consistent with the Gaussian 3D function, which expresses an idealized distribution that meets the preferences of the polar water environment. The varied degrees of compatibility of the distribution observed with the idealized one allow the prediction of preferences to interactions with molecules of different polarity, including water molecules in particular. This paper analyzes a set of proteins with different levels of hydrophobicity distribution in the context of the solubility of a given protein and the possibility of complex formation.