Particle size,rheological and structural properties of whole wheat flour doughs as treated by high pressure

Effect of high-pressure treatment (300–600 MPa) and flour-to-water ratio (1:1, 1:2, 1:3, and 1:4) on functional, rheological, thermal, and structural properties of whole wheat flour dough were investigated. The particle size distribution, especially Dv90 (90% of the volume distribution), was significantly reduced by the pressure treatment. The damaged starch content increased significantly with the applied pressure and water content. The damaged starch absorbed more water, and subsequently increased the water holding capacity. Thermal transitions and mechanical property of pressure-treated samples were measured by differential scanning calorimetry, and rheometry, respectively. The peak viscosity, hot paste viscosity, and final viscosity decreased significantly with increasing pressure intensity. Hardness increased with the increasing pressure level while stickiness decreased at similar conditions. Fourier-transform infrared spectroscopy showed changes in the amide I region of the wheat protein. The sodium dodecyl sulfate polyacrylamide gel electrophoresis further indicated changes in the protein subunits that occurred after pressurization.     

Studies to analyse the relationship between IFNα2b gene dosage and its expression,using a Pichia pastoris‐based expression system

Human interferon α2b (hIFNα2b) is the most important member of the interferon family. Escherichia coli, yeasts, mammalian cell cultures and baculovirus‐infected insect cells have been used for expressing recombinant human interferon. Recently a Pichia pastoris‐based expression system has emerged as an attractive system for producing functional human recombinant IFNα2b. In this regard, gene dosage is considered an important factor in obtaining the optimum expression of recombinant protein, which may vary from one protein to another. In the present study we have shown the effect of IFNα2b gene dosage on extracellular expression of IFNα2b recombinant protein from P. pastoris. Constructs containing from one to five repeats of IFNα2b‐expressing cassettes were created via an in vitro multimerization approach. P. pastoris host strain X‐33 was transformed using these expression cassettes. Groups of P. pastoris clones transformed with different copies of the IFNα2b expression cassette were screened for intrachromosomal integration. The IFNα2b expression level of stable transformants was checked. The copy number of integrated IFNα2b was determined by performing qPCR of genomic DNA of recombinant P. patoris clones. It was observed that an increase in copy number generally had a positive effect on the expression level of IFNα2b protein. Regarding the performance of multicopy strains, those obtained from transformation of multicopy vectors showed relatively high expression, compared to those generated using transformation vector having only one copy of IFNα2b. It was also observed that an increase in drug resistance of a clone did not guarantee its high expression, as integration of a marker gene did not always correlate with integration of the gene of interest. Copyright © 2013 John Wiley & Sons, Ltd.     

A protein which masks galactose receptor mediated phage susceptibility in Lactococcus lactis subsp. lactis MPL56

A 28.5-kb plasmid, isolated from Lactococcus lactis subsp. lactis MPL56, causes complete inhibition of four lactococcal phages. Cell wall characteristics of wild-type strain MPL56 were compared with its 28.5 kb plasmid-cured, phage-sensitive derivative MPL56-22. After proteolytic enzyme treatments, adsorption of phages occurred at high levels, an example is 94.6–98.5% in MPL56 cells. Analysis of cell wall extracts of MPL56-22 by sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) indicated that the only difference between strains was the 55.4 kDa band in protein patterns of MPL56. Adsorption of the four phages was completely inhibited when MPL56-22 cells were subjected to SDS, Triton-X-100, HCl and NaOH treatments. Lectins that were specific for glucose/mannose and N-acetylglucosamine did not prevent adsorption of phages in cell wall extracts of MPL 56-22. However a lectin specific for galactose (MCA; Momordica charantia ) completely inhibited adsorption of these phages in cell wall extracts of MPL56-22. HPLC patterns of cell wall carbohydrates of MPL56-22 and its HCl treated preparations showed that the most prevalent difference was the galactose on untreated MPL56-22 cell wall chromatograms.     

An Overview on SARS‑CoV‑2(COVID‑19)and Other Human Coronaviruses and Their Detection Capability via Amplification Assay,Chemical Sensing,Biosensing,Immunosensing,and Clinical Assays

A novel coronavirus of zoonotic origin(SARSCoV-2)has recently been recognized in patients with acute respiratory disease.COVID-19 causative agent is structurally and genetically similar to SARS and bat SARS-like coronaviruses.The drastic increase in the number of coronavirus and its genome sequence have given us an unprecedented opportunity to perform bioinformatics and genomics analysis on this class of viruses.Clinical tests like PCR and ELISA for rapid detection of this virus are urgently needed for early identification of infected patients.However,these techniques are expensive and not readily available for point-of-care(POC)applications.Currently,lack of any rapid,available,and reliable POC detection method gives rise to the progression of COVID-19 as a horrible global problem.To solve the negative features of clinical investigation,we provide a brief introduction of the general features of coronaviruses and describe various amplification assays,sensing,biosensing,immunosensing,and aptasensing for the determination of various groups of coronaviruses applied as a template for the detection of SARS-CoV-2.All sensing and biosensing techniques developed for the determination of various classes of coronaviruses are useful to recognize the newly immerged coronavirus,i.e.,SARS-CoV-2.Also,the introduction of sensing and biosensing methods sheds light on the way of designing a proper screening system to detect the virus at the early stage of infection to tranquilize the speed and vastity of spreading.Among other approaches investigated among molecular approaches and PCR or recognition of viral diseases,LAMP-based methods and LFAs are of great importance for their numerous benefits,which can be helpful to design a universal platform for detection of future emerging pathogenic viruses.     

Identifying critical autonomous systems in the Internet

The Internet not only facilitates our daily activities, such as communication, entertainment and shopping but also serves as the enabling technology for many critical services, including finance, manufacturing, healthcare and transportation. On the other hand, a wide spectrum of attacks targets its communication infrastructure to disable or disrupt the network connectivity and traffic flow until recovery processes take place. Attacking all autonomous systems (ASes) in the Internet is typically beyond the capability of an adversary. Therefore, targeting a small number of ASes which results in the highest impact is the best strategy for attackers. Similarly, it is important for network practitioners to identify, fortify and secure those critical ASes to mitigate the impact of the attacks. In this study we introduce an intuitive and effective measure, IP address spatial path stress centrality, to assess and identify the critical ASes in the Internet. We compare IP address spatial path stress centrality to the three well-known and widely used centrality measures, namely customer-cone size, node degree and betweenness. We demonstrate that the proposed measure incorporates business relations and IP address spaces to achieve a better measure for identifying the critical ASes in the Internet.     

Studies on Ambient Cured Biobased Mn(II), Co(II) and Cu(II) Containing Metallopolyesteramides

In this paper linseed oil based metallopolyesteramides (Mn(II)-/Co(II)-/Cu(II)-LPEA) containing metals [with half filled (d ⁵) and partially filled (d ⁷ and d ⁹) d orbitals] were synthesized via green route for the application of eco-friendly protective green material. This paper also described the role of occupancy of d orbitals on the performance of such polymers. The synthesis reaction was carried out in situ through condensation polymerization among linseed fatty amide diol (HELA), phthalic anhydride and respective metal acetates [M (OCOCH₃)₂; M = Mn(II), Co(II), Cu(II); different mole ratios] in absence of any harmful organic solvent. The structural determination (FTIR, ¹H-NMR and ¹³C-NMR), curing, thermal, physico-chemical, physico-mechanical, anticorrosive/chemical resistance, antibacterial properties of Mn(II)-/Co(II)-/Cu(II)-LPEA were carried out. The curing mechanism of the resin was confirmed by the comparison of FTIR spectra of uncured and cured resin. The curing mechanism of Mn(II)-/Co(II)-/Cu(II)-LPEA is found to be contrary to that of reported oil based polymer that involves the lipid autoxidation (slow process) in which driers are required to speed up the room temperature curing process. The incorporation of metals in Mn(II)-/Co(II)-/Cu(II)-LPEA improved the thermal stability as compared to virgin linseed oil based polyesteramide (LPEA). Mn(II)-/Co(II)-/Cu(II)-LPEA also show excellent antibacterial performance against Staphylococcus aureus and Escherichia coli. The observed diversity in material properties suggests that Mn-LPEA may be useful as an eco-friendly protective green material with thermal stability up to 320–330 °C.     

Synthesis and Characterization of Ricinoleamide-Based Polyurethane

Ricinus communis (RC) oil-based materials are currently receiving increasing attention because of economic and environmental concerns. In the present work, RC oil—a natural triol has been utilized for the development of an advanced polymeric material—poly(urethane-ricinoleamide) (PUR) through very simple synthesis and curing strategy, omitting derivatization steps or side reactions, chain extenders and crosslinkers. The synthesis of PUR was carried out in two steps. The first step is the introduction of an amide group in the RC oil (89.5% ricinoleic acid) via base catalyzed amidation, which results in N, N-bis (2-hydroxyethyl) ricinoleamide (HERA). The second step is urethanation of HERA by the reaction of toluene-2,4-diisocyanate (TDI) in minimal possible organic solvent by one-shot technique, which results in the formation of polyurethane along with amide linkages. The physico-chemical and spectral studies (FT-IR, ¹H-NMR and ¹³C-NMR techniques) confirm these two reactions and the structure of PUR. The resin was cured at ambient temperature without any cross linker. Solubility of the resin was investigated in different polar and non-polar solvents. Thermo-gravimetric analysis (TGA)/differential thermal analysis (DTA) and Differential Scanning Calorimetry (DSC) were used to determine the thermal stability and curing behavior of PUR. An ambient cured ricinoleamide modified polyurethane resin exhibited thermal resistance up to 200–220 °C.     

Electrochemistry, spectroelectrochemistry and electrochemical polymerization of titanylphthalocyanines

Detailed electrochemical characterization of tetrakis(2-dimethylaminoethylsulfanyl phthalocyaninato) oxotitanium(IV) and octakis(2-dimethylaminoethylsulfanyl phthalocyaninato) oxotitanium(IV) derivatives has been carried out by the cyclic voltammetry, differential pulse voltammetry, controlled potential chronocoulometry and spectroelectrochemical measurements. Cyclic and differential pulse voltammograms of both complexes are similar, with two metal-based and one ligand-based reduction couples having diffusion controlled reversible one-electron transfer character. Both complexes are polymerized on the working electrode electrochemically during the positive potential sweeps. Spectroelectrochemical measurements confirm the metal and ligand-based assignments of the redox couples.