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关键词： Dust particle aging   Physico-chemical characterization   SEM-EDS   XPS   XRF  

摘要： The physico-chemical properties of dust particles collected During Dust Storm (DDS) and After Dust Storm (ADS) events were studied using Scanning Electron Microscope coupled with Energy Dispersive Xray Spectroscopy (SEM-EDS), X-ray Fluorescence Spectroscopy (XRF) and X-ray Photoelectron Spectroscopy (XPS). Morphological and compositional change in dust particles were observed as they react with the anthropogenic pollutants present in the urban environment. The calcite rich particles were observed to transform into calcium chloride, calcium nitrate, and calcium sulfate on reacting with the chlorides, nitrates, and sulfates present in the urban atmosphere. The frequency distributions of Aspect Ratio (AR) for the DDS and ADS particles were observed to be bimodal (mode peaks at 1.2 and 1.5) and monomodal (mode peak at 1.1), respectively. The highly irregular shaped solid dust particles were observed to transform into nearly spherical semisolid particles in the urban environment. XPS analysis confirms the high concentration of oxides, nitrates, and chlorides at the surface of ADS samples which show the signatures of mineral dust particles aging. Species with a high value of imaginary part of refractive index (like Cr metal, Fe metal, Cr2O3, FeO, Fe2O3) were observed at the surface of dust particles. At 550 nm wavelength, the light-absorbing potential of the observed species along with black carbon (BC) was found to vary in the order;Cr metal > Fe metal > Cr2O3> FeO > BC > Fe2O3> FeOOH. The presence of the aforementioned species on the surface of ADS particles will tremendously affect the particle optical and radiative properties compared to that of DDS particles. The present work could reduce the uncertainty in the radiation budget estimations of mineral dust and assessment of their climatic impacts over Delhi. (c) 2020 Elsevier Ltd. All rights reserved.

关键词： Functional properties   Mung bean   Pilot scale extraction   Protein characterization   Sustainable food  

摘要： Mung bean is an inexpensive yet sustainable protein source. Current work compared the effects of freeze (FD), spray (SD) and oven drying (OD), on mung bean protein isolate (MBPI) produced on pilot scale. All samples showed no dissociation of protein subunits and were thermally stable (T-d = 157.90-158.07 degrees C). According to morphological studies, FD formed a porous protein while SD and OD formed wrinkled and compact crystals, respectively. FD and SD formed elastic gels with better gelling capacity than OD (aggregated gel). FD showed exceptional protein solubility, water and oil absorption capacity (4.23 g/g and 8.38 g/g, respectively). SD demonstrated the smallest particle size, excellent emulsion activity index (29.21 m(2)/g) and stability (351.90 min) and the highest beta-sheet amount (37.61%). FTIR spectra for all samples showed characteristic peaks which corresponded well to the secondary structure of legume proteins. Rheological analysis revealed that gelation temperature for all MBPI lied around 90 degrees C. Current work described the different final properties achieved for MBPI produced under different drying techniques that allowed tailoring for different food systems, whereby FD is ideal for meat extender, SD is suitable for meat emulsion while OD is suitable in general protein-based application.

关键词： Myelin   Nerve conduction   ATP   Mitochondria   Gap junctions  

摘要： The existence of different conductive patterns in unmyelinated and myelinated axons is uncertain. It seems that considering exclusively physical electrical phenomena may be an oversimplification. A novel interpretation of the mechanism of nerve conduction in myelinated nerves is proposed, to explain how the basic mechanism of nerve conduction has been adapted to myelinated conditions. The neurilemma would bear the voltage-gated channels and Na+/K+-ATPase in both unmyelinated and myelinated conditions, the only difference being the sheath wrapping it. The dramatic increase in conduction speed of the myelinated axons would essentially depend on an increment in ATP availability within the inter-node: myelin would be an aerobic ATP supplier to the axoplasm, through connexons. In fact, neurons rely on aerobic metabolism and on trophic support from oligodendrocytes, that do not normally duplicate after infancy in humans. Such comprehensive framework of nerve impulse propagation in axons may shed new light on the pathophysiology of nervous system disease in humans, seemingly strictly dependent on the viability of the pre-existing oligodendrocyte.

关键词： shear strength   ring shear test   saline solution   intergranular stress   clayey soils  

摘要： Pore fluid chemistry can significantly influence the shear strength characteristics of a clayey soil. To explore the underlying mechanisms, a series of ring shear experiments are performed on two natural clays, which represent two typical types of clayey minerals, i.e., expansive montmorillonitic clay and low-plasticity kaolinitic clay. The effects of pore solution concentrations on the shear strength of the two clays are experimentally characterized. It is shown that the shear strength of the expansive clay can be significantly influenced by the pore solution chemistry, whereas that of the low-plasticity clay proves to be relatively insensitive to it. To capture the main features of the shear strength behavior of clayey soils, the concept of intergranular stress, which is an extension of the Terzaglirs effective stress to incorporate physicochemical effect, is introduced to interpret the experimental data. It is found that the evolution of residual shear strength can be very well characterized by using the intergranular stress, showing that the proposed intergranular stress formulation can be used alternatively to describe the stress state of clayey soils saturated with various pore solutions.

关键词： Lactic acid bacteria   P   acidilactici   Peptidoglycan hydrolases   Probiotics   Antibacterial activity  

摘要： Pediococcus acidilactici NCDC 252 is a Gram-positive lactic acid bacteria (LAB) that is being studied to develop it as probiotic and starter culture for dairy and meat industry. Peptidoglycan hydrolases (PGHs) are also gaining interest because of their antibacterial activity. NCDC 252 genome was searched for PGH encoded genes and product of these genes were in silico characterized for different parameters. Extracellular PGHs of NCDC 252 were precipitated and characterized. PGHs were screened turbidometrically with Bacillus cereus and Staphylococcus albus as substrates. Spectrum of PGH(s) was studied in renaturing SDS-PAGE by varying substrates and renaturing conditions. PGH(s) band intensity decreased in the presence of NaCl whereas some additional secondary lytic bands appeared in the presence of EDTA. Autolysis of LAB in cheese and other fermented food products is associated with release of oligopeptides by proteolysis and other enzyme activities. Autolytic phenotype of P. acidilactici was evaluated and characterized. Lytic activity studies revealed 45-60% activity against Micrococcus lysodeikticus and B. cereus greater than for P. acidilactici. PGH of P. acidilactici exhibited broad growth inhibiting spectrum of antibacterial activity against studied Gram positive and Gram negative bacteria and thus can be promising in controlling pathogenic bacteria. This also confers probiotic attribute to the studied strain.

关键词： Green coffee spent   Physicochemical   Nutritional   Prebiotic coffee cookies   Functional food  

摘要： The present work aimed to valorize green coffee spent (GCS) as a food ingredient and its application in food products. About 70% of GCS was obtained after processing green coffee for Chlomgenic acid. The cookies fortified with roasted green coffee spent (RGCS) and unmasted green coffee spent (UGCS) were evaluated for physicochemical properties and food safety. The UGCS and RGCS flour had dietary fiber ranging from 3.3 +/- 1.08 and 2.6 +/- 0.21%, total polysaccharides with 8.29 +/- 0.05 and 16.34 mu g/Mg along with fair amount of ash and protein. They also recorded 36.4 and 32.6 mg/100g of polyphenols and 0.32 and 1.25% Tmlox equivalent antioxidant activity The UGCS and RGCS contained 4.76 and 8.29 mu g/Mg oligosaccharides respectively. The UGCS and RGCS recorded The acrylamide in UGCS and RGCS cookies was 23.4-37.8 +/- 0.3 lg ACR/kg d.m. The cookies formulations of RGCS had better sensory attributes such as color and aroma. Thus, RGCS enriched with prebiotic oligosaccharide represent novel functional food supplement.

关键词： Hydroxychloroquine   Oral suspension   SARS-CoV-2   Stability-indicating assay  

摘要： In the context of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, hydroxy-chloroquine has been proposed as a potential agent to treat patients with COVID-19 (coronavirus disease 2019) caused by SARS-CoV-2 infection. Older adults are more susceptible to COVID-19 and some patients may require admission to the intensive care unit, where oral drug administration of solid forms may be compromised in many COVID-19 patients. However, a liquid formulation of hydroxychloroquine is not commercially available. This study describes how to prepare a 50 mg/mL hydroxychloroquine oral suspension using hydroxychloroquine sulfate powder and SyrSpend (R) SF PH4 (dry) suspending vehicle. Moreover, a fully validated stability-indicating method has been developed to demonstrate the physicochemical stability of the compounded hydroxychloroquine oral suspension over 60 days under refrigeration (5 +/- 3 degrees C). Finally, use of the proposed oral suspension provides a reliable solution to perform safe and accurate administration of hydroxychloroquine to patients with SARS-CoV-2 infection. (C) 2020 Elsevier Ltd and International Society of Antimicrobial Chemotherapy. All rights reserved.

关键词： pectin   ferulic acid   free-radical-mediated grafting   characterization   antioxidant activity  

摘要： BACKGROUND Pectin, as a functional ingredient, is best known as a gelling and thickening agent, stabilizer, and fat substitute in processed foods. The synthesis of pectin graft copolymers is considered one of the most fascinating ways to improve its physicochemical and functional properties. In this study, therefore, water-soluble pectin or ultrasound-treated pectins (UP30 and UP60) grafted with ferulic acid (FA) conjugates, pectin-g-FA, UP30-g-FA and UP60-g-FA, were synthesized via a free radical-mediated grafting procedure, and their physicochemical, structural, and functional characteristics were investigated. Moreover, 2,2-diphenyl-1-picryl-hydrazyl (DPPH)-radical scavenging activity, Trolox equivalent antioxidant capacity (TEAC) assay and ferric-reducing ability of plasma (FRAP) assay were used to evaluate their antioxidant activitiesin vitro. RESULTS Results showed that FA was covalently grafted onto pectin or ultrasound-treated pectins, and the grafting ratios of pectin-g-FA, UP30-g-FA and UP60-g-FA were 65.43 +/- 1.30, 82.55 +/- 1.71 and 75.82 +/- 0.89 mg FA/g, respectively. Although the molecular weights, apparent viscosities, and thermal stabilities of the three FA-grafted pectin conjugates decreased and their surface morphologies were different from those of native pectin and ultrasound-treated pectins, they possessed prominent DPPH-radical scavenging ability [half maximal inhibitory concentration (IC50) of 0.32 to 0.89 mg mL(-1)) and antioxidant capacity (TEAC of 100.02 to 153.42 mu mol Trolox/g sample;FRAP: 166.41 to 270.27 mu mol FeSO4/g sample). Their antioxidant potentials were positively correlated with the grafting ratio. CONCLUSION This study provided a promising strategy for the functionalization of pectin, and the prepared FA-grafted pectin conjugates could be explored as functional ingredients that showed potential for applications in food and agriculture systems. (c) 2020 Society of Chemical Industry

关键词： Potato cultivars   Irradiation   Electron beam   Storage   Sprouting   Reducing sugars  

摘要： This study evaluated the effects of three electron beam (e-beam) levels (0, 500 and 1000 Gy) on the sprouting and physico-chemical properties of five potato cultivars (Arinda, Burren, Sante, Agriya and Marfona) stored at 10 degrees C for 180 days. Sprouting of all cultivars was entirely inhibited by e-beam irradiation. The contents of sucrose and reducing sugars (glucose and fructose) and the weight loss of tubers were increased while the tuber firmness and starch content were decreased over the cold storage period. Potato cultivar differences were evident in tuber weight loss, starch and sugars contents and the activity of alpha-amylase but not for firmnessand titratable acidity. The reductions in firmness and weight loss measured at days 90 and 180 after storage were less in the irradiated than in non-irradiated tubers. The contents of reducing sugars in tubers were in most cases increased bye-beam, especially at higher dose of irradiation. Titratable acidity was reduced but alpha-amylase activity was increased only immediately after irradiation. The results from this study showed that e-beam irradiation, regardless of cultivar, inhibited sprouting and decreased loss weight and firmness but except in Buren cultivar at low dose of irradiation increased the content of reducing sugars in the potato tubers stored at 10 degrees C.

关键词： Metal(loid) contamination   metal(loid) bioavailability   Metal-microbe interaction   Ecological process  

摘要： Heavy metal contamination poses considerable threats to various ecosystems, yet little is known about the assembly and adaptation of microbial communities at sites with combined heavy metal(loid) pollution. Here, we examined metal(loid) pollutants and bacterial communities in three zones (Zones I, II, and III) of an abandoned sewage reservoir with different usage years. The contamination level of multiple metal(loid)s was higher in Zone I than in the other zones, and arsenic (As), zinc (Zn), selenium (Se), copper (Cu), tin (Sn), molybdenum (Mo), antimony (Sb), cadmium (Cd), lead (Pb), thallium (TI), and nickel (Ni) were the major contaminants (pollution load index > 1). Bioavailable forms of titanium (Ti), chromium (Cr), Sn, and cobalt (Co) played essential roles in shaping the microbial structure, and physicochemical properties, especially organic matter (OM) and pH, also mediated the microbial diversity and composition in the metal(loid) contaminated zones. Metal-microbe interactions and heatmap analysis revealed that the bioavailability of metal(loid)s promoted the niche partitioning of microbial species. Metal-resistant species were abundant in Zone I that had the highest metal-contaminated level, whereas metal-sensitive species prevailed in Zone III that had the lowest pollution level. The bioavailable metal(loid)s rather than physicochemical and spatial variables explained a larger portion of the variance in the microbial community, and the homogeneous selection was the dominant ecological process driving the assembly of the microbial community. Overall, our study highlighted the importance of metal(loid) bioavailability in shaping microbial structure, future bioremediation, and environmental management of metal(loid) contaminated sites. (C) 2020 Elsevier Ltd. All rights reserved.