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Cation-intercalated graphene oxide (GO) membrane has emerged as a promising candidate for desalination applications as reverse osmosis (RO) membrane. This study constructs GO membranes with different cations (K+ or Mg2+) and investigates the potential of these membranes in boron removal via nonequilibrium molecular dynamics simulations. In the aquatic environment, boron can exist in the form of boric acid or borate ion, depending on the pH of the solution. As a result, this study considers two forms of boron. This study reveals that the GO membranes effectively reject negatively charged borate ions due to their bigger hydration shell and stronger electrostatic repulsion with the membrane than neutral boric acid molecules. Moreover, K+ ion intercalated GO membranes showed higher boron rejection than Mg2+ ion intercalated GO membranes owing to weaker electrostatic attraction of K+ ions with the boric acid (or borate ions). Additionally, a summary of the effects of oxygen-containing functional groups of the GO membrane on boron rejection is provided. Since the hydroxyl and epoxy functional groups interact with boric acid molecules more strongly, these molecules are prevented from permeating through the membrane. On the other hand, the permeation rate of borate ions declines because of their stronger interactions with the carboxyl functional groups. Furthermore, Mg2+ ion intercalated GO membranes exhibited higher water permeance, excellent Na+ rejection, and poor Cl− rejection compared to K+ ion intercalated GO membranes. • The effects of intercalated cations inside the GO layers on boron rejection are investigated. • GO membranes reject borate ions effectively when compared to boric acid. • The impact of oxygen-containing functional groups of GO membranes on boron rejection is presented. [ABSTRACT FROM AUTHOR]

The AB 5 type toxin produced by the Vibrio cholerae bacterium is the causative agent of the cholera disease. The cholera toxin (CT) has been shown to bind specifically to GM1 glycolipids on the membrane surface. This binding of CT to the membrane is the initial step in its endocytosis and has been postulated to cause significant disruption to the membrane structure. In this work, we have carried out a combination of coarse-grain and atomistic simulations to study the binding of CT to a membrane modelled as an asymmetrical GM1-DPPC bilayer. Simulation results indicate that the toxin binds to the membrane through only three of its five B subunits, in effect resulting in a tilted bound configuration. Additionally, the binding of the CT can increase the area per lipid of GM1 leaflet, which in turn can cause the membrane regions interacting with the bound subunits to experience significant bilayer thinning and lipid tail disorder across both the leaflets. [ABSTRACT FROM AUTHOR]

The properties of lipid bilayers in contact with trehalose solutions in water were studied in the full concentration range using molecular dynamics simulations. The mechanism of trehalose interaction with the bilayer surface was analysed considering hydrogen bonding and molecular arrangements as well as the possible changes in bilayer properties. The effect of concentration of the possible mechanisms of trehalose action as membrane protectant were discussed to infer the possible evolution of water replacement by trehalose at the membrane surface and its relationship with the trehalose role in anhydrobiosis and drying processes. Unlabelled Image • Anhidrobiosis in presence of trehalose • Trehalose solution in presence interacting with lipid membranes • Water replacement mechanisms • Intermolecular forces at lipid bilayer interfaces • Nanoscopic characterization of bilayer structuring upon water replacement [ABSTRACT FROM AUTHOR]

[Display omitted] • Spectral methods have been used to investigate the interaction of R1 with HHb and BSA. • Thermodynamic parameters suggested exothermic spontaneous binding processes involving hydrogen bonding and van der Waal interaction. • Molecular docking and molecular dynamics have been utilized to discuss the principle binding sites of proteins for R1. • R1 proposes preferentially binding to the hydrophobic cavity in site III of proteins. A Rhodamine-based fluorescent probe R1 has been successfully utilized to detect BSA and HHb proteins via non-covalent bonding. The protein binding nature with R1 has been unravelled by the characteristic changes in absorption, emission and circular dichroism spectra that indicated their noticeable interaction. The experimental results have also shown the moderate strength between proteins and R1 from the quenching of proteins through the static quenching mechanism. The hyperchromism in the absorption band of proteins with R1 has given vital information and binding affinity values have been calculated from Stern-Volmer plots. The calculated values of the thermodynamic parameters revealed a spontaneous binding processes occurring primarily via hydrogen bonding and van der Waal interactions. Furthermore, in-silico approaches have been utilized to make a comparison and conclusion with spectroscopic results. The outcome of these studies could be useful to examine the drug-protein binding for further exploitation. [ABSTRACT FROM AUTHOR]

Xanthine oxidase (XO) plays a critical role in purine catabolism, catalyzing the conversion of hypoxanthine to xanthine and xanthine to uric acid, contributing to superoxide anion production. This process is implicated in various human diseases, particularly gout. Traditional XO inhibitors, such as allopurinol and febuxostat, while effective, may present side effects. Our study focuses on Asphodelus microcarpus , a plant renowned for traditional anti-inflammatory uses. Recent investigations into its phenolic-rich flowers, notably abundant in luteolin derivatives, reveal its potential as a natural source of XO inhibitors. In the present research, XO inhibition by an ethanolic flowers extract from A. microcarpus is reported. In silico docking studies have highlighted luteolin derivatives as potential XO inhibitors, and molecular dynamics support that luteolin 7- O -glucoside has the highest binding stability compared to other compounds and controls. In vitro studies confirm that luteolin 7- O -glucoside inhibits XO more effectively than the standard inhibitor allopurinol, with an IC 50 value of 4.8 μg/mL compared to 11.5 μg/mL, respectively. These findings underscore the potential therapeutic significance of A. microcarpus in managing conditions related to XO activity. The research contributes valuable insights into the health-promoting properties of A. microcarpus and its potential application in natural medicine, presenting a promising avenue for further exploration in disease management. • A. microcarpus flower extract inhibits xanthine oxidase (XO) via mixed-type inhibition. • Luteolin-7- O -glucoside stably binds XO in AutoDock and 250ns molecular dynamics. • Luteolin 7- O -glucoside demonstrates in vitro XO inhibition (IC 50 4.8 μg/mL). [ABSTRACT FROM AUTHOR]

Deep eutectic solvents, a new genre of green solvent, easy to synthesize, low volatility and non-toxic in nature, emerged as an efficient extractant for denitrogenation. We have performed a molecular dynamics simulation study to investigate the role of glyceline as an extractant for removal of nitrogen impurities namely indole, pyrrole, pyridine, and quinoline from a model liquid fuel. Δ G transfer was evaluated to capture the thermodynamic feasibility of the transfer of nitrogen impurities from the fuel to the glyceline phase. Negative value of Δ G transfer was obtained for the nitrogen impurities, and the partition coefficient in the following order: indole > pyrrole > quinoline > pyridine. The simulation revealed that the chloride-ion possesses strong interaction with indole and pyrrole while glycerol favors quinoline and pyridine. The fuel phase was observed to be free from impurities while glyceline phase contained impurities, which was confirmed by the negative and positive values of Δ G transfer and partition coefficient respectively. The self-diffusion coefficient for indole was observed to be the lowest while pyridine possesses the highest value, which was found to be in agreement with the observations from radial and spatial distribution functions. Further, this understanding at the atomic level for liquid-liquid extraction will help in developing potential solvents for denitrogenation of liquid fuel. • A negative value of Δ G transfer indicates the thermodynamically favorable separation. • Trend of the partition coefficient follows indole > pyrrole > quinoline > pyridine. • Lowest and highest D self values were observed for indole and pyridine respectively. • Phase separation between fuel oil and deep eutectic solvent was clearly observed. [ABSTRACT FROM AUTHOR]

Abstract: Angiogenesis is the formation of new blood vessels from existing blood vessels and is critical for many physiological and pathophysiological processes. In this study we have shown the unique property of cerium oxide nanoparticles (CNPs) to induce angiogenesis, observed using both in vitro and in vivo model systems. In particular, CNPs trigger angiogenesis by modulating the intracellular oxygen environment and stabilizing hypoxia inducing factor 1α endogenously. Furthermore, correlations between angiogenesis induction and CNPs physicochemical properties including: surface Ce3+/Ce4+ ratio, surface charge, size, and shape were also explored. High surface area and increased Ce3+/Ce4+ ratio make CNPs more catalytically active towards regulating intracellular oxygen, which in turn led to more robust induction of angiogenesis. Atomistic simulation was also used, in partnership with in vitro and in vivo experimentation, to reveal that the surface reactivity of CNPs and facile oxygen transport promotes pro-angiogenesis. [Copyright &y& Elsevier]