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A natural and sustainable alternative to conventional solvents in terms of solubilization and extraction of curcuminoids from Curcuma longa L. was investigated by examining different naturally occurring aroma compounds and cinnamon oils.

The monoammonium salt of glycyrrhizic acid (AGA) is known to form fibrillar hydrogels and few studies regarding self-assembly of AGA have been published. Yet, the understanding of the fibrillar microstructures and the gelation remains vague. Thus, we attempt to achieve a deeper understanding of the microstructures and the gelation process of binary solutions of AGA in water. Further, we examine the effect of ethanol on the microstructures to pave the way for potential enhancement of drug loading in AGA hydrogels.A partial room temperature phase map of the ternary system AGA/ethanol/water was recorded. Small-angle X-ray and neutron scattering experiments were performed over wide ranges of compositions in both binary AGA/water and ternary AGA/ethanol/water mixtures to get access to the micro-structuring.Binary aqueous solutions of AGA form birefringent gels consisting of a network of long helical fibrils. 'Infinitely' long negatively charged fibrils are in equilibrium with shorter fibrils (≈25 nm), both of which have a diameter of about 3 nm and are made of around 30 stacks of AGA per helical period (≈9nm), with each stack consisting of two AGA molecules. The interaxial distance (order of magnitude ≈20 nm) varies with an almost two-dimensional swelling law. Addition of ethanol reduces electrostatic repulsion and favors the formation of fibrillar end caps, reducing the average length of shorter fibrils, as well as the formation of small, swollen aggregates. While the gel network built by the long fibrils is resilient to a significant amount of ethanol, all fibrils are finally dissolved into small aggregates above a certain threshold concentration of ethanol (≈30 wt%).

In a recent paper, we determined the phase behavior of an aqueous solution of octyl ether octaethylene oxide carboxylic acid ([HWe established the respective phase diagrams of the above-mentioned salts in water and determined the structures of the occurring phases in detail with small-and wide-angle X-ray scattering, small-angle neutron scattering, dynamic light scattering, heat flux differential scanning calorimetry, as well as surface tension, ESI-MS, and NMR experiments.To our surprise, we discovered a new type of nematic phase between an isotropic and a hexagonal phase. Based on the complete description of all occurring phases both in the acidic and the charged surfactant systems, we were able to design a coherent and unified picture of all these phases, including the auto-coacervation at low surfactant concentration, the non-conventional clouding at high temperatures, the unusual liquid crystalline phases in a small domain at high surfactant concentrations, and the L

Chemical gardens are self-assembled structures with intricate plant-like morphologies and consist of mineralized membranes, which form spontaneously at interfaces between compartments with dissimilar chemical composition, most typically acidic metal salt and alkaline sodium silicate solutions. While this phenomenon is thought to occur in a number of practical settings, it has also proven to be valuable for investigating transport characteristics in distinct applied systems. For example, coupled diffusion and precipitation processes were monitored in silica gardens based on calcium and iron salts, considered to be models for cement hydration and steel corrosion, respectively. Here we extend these studies to the case of aluminum-based silica gardens, one of the so far less frequently investigated examples of silica gardens. To this end, single macroscopic tubes were prepared in a reproducible way by the controlled addition of sodium silicate solution to a pellet of pressed aluminum nitrate. Continued sampling of the volumes enclosed by and surrounding the formed membraneous structure allowed the time-dependent development of ion concentration gradients to be tracked over extended periods of time, while both the pH and electrochemical potential differences across the membrane were recorded online by immersed probes. The dynamic behavior revealed in this way was finally complemented by ex-situ analyses of the composition of the formed tubes. The collected data shows that the as-prepared tubular structures consist of sodium aluminosilicate phases with certain similarities to zeolites and geopolymers. The emerging tube wall was further found to be permeable to all ionic species present in the system, allowing significant electrochemical potential to be sustained over tens of hours until diffusion had eventually diminished the initially generated gradients. The findings of this work may have important implications for the geochemical fate of natural aluminosilicate sources, the use of such geopolymers in construction applications, and the synthesis and properties of zeolites.

Chemical gardens are tubular inorganic structures exhibiting complex morphologies and interesting dynamic properties upon ageing, with coupled diffusion and precipitation processes keeping the systems out of equilibrium for extended periods of time. Calcium-based silica gardens should comprise membranes that mimic the microstructures occurring in ordinary Portland cement and/or silicate gel layers observed around highly reactive siliceous aggregates in concrete.Single macroscopic silica garden tubes were prepared using pellets of calcium chloride and sodium silicate solution. The composition of the mineralized tubes was characterized by means of various ex-situ techniques, while time-dependent monitoring of the solutions enclosed by and surrounding the membrane gives insight into the spatiotemporal distribution of the different ionic species. The latter data reflect transport properties and precipitation reactions in the system, thus allowing its complex dynamic behavior to be resolved.The results show that in contrast to the previously studied cases of iron- and cobalt-based silica gardens, the formed calcium silicate membrane is homogeneous and ultimately becomes impermeable to all species except water, hydroxide and sodium ions, resulting in the permanent conservation of considerable concentration gradients across the membrane. The insights gained in this work may help elucidate the nature and mechanisms of ion diffusion in Portland cements and concrete, especially those occurring during initial hydration of calcium silicates and the so-called alkali-silica reaction (ASR), one of the major concrete deterioration mechanisms causing serious problems with respect to the durability of concrete and the restricted use of many potential sources of raw materials.

PurposeService robots are now an integral part of people's living and working environment, making service robots one of the hot topics for service researchers today. Against that background, the paper reviews the recent service robot literature following a Theory-Context-Characteristics-Methodology (TCCM) approach to capture the state of art of the field. In addition, building on qualitative input from researchers who are active in this field, the authors highlight where opportunities for further development and growth lie.Design/methodology/approachThe paper identifies and analyzes 88 manuscripts (featuring 173 individual studies) published in academic journals featured on the SERVSIG literature alert. In addition, qualitative input gathered from 79 researchers who are active in the service field and doing research on service robots is infused throughout the manuscript.FindingsThe key research foci of the service robot literature to date include comparing service robots with humans, the role of service robots' look and feel, consumer attitudes toward service robots and the role of service robot conversational skills and behaviors. From a TCCM view, the authors discern dominant theories (anthropomorphism theory), contexts (retail/healthcare, USA samples, Business-to-Consumer (B2C) settings and customer focused), study characteristics (robot types: chatbots, not embodied and text/voice-based; outcome focus: customer intentions) and methodologies (experimental, picture-based scenarios).Originality/valueThe current paper is the first to analyze the service robot literature from a TCCM perspective. Doing so, the study gives (1) a comprehensive picture of the field to date and (2) highlights key pathways to inspire future work.

Phosphorylated resveratrol can prevent the aggregation of globular and intrinsically disordered proteins in vitro and in vivo.

Phase selection during precipitation of calcium sulfate is known to be influenced by various parameters. Here we demonstrate that the relative level of supersaturation determines whether more or less hydrated crystalline phases are formed.

Choline alkoxylates were synthesised and used to solubilise long-chain surfactants under ambient conditions. In this way, so far underutilised natural feedstocks could be leveraged for the design of sustainable and efficient cleaning formulations.

The amino alcohol meglumine solubilizes organic compounds in water and enforces the formation of electron donor acceptor (EDA) complexes of haloarenes with indoles, anilines, anisoles or thiols, which are not observed in organic solvents. UV-A photoinduced electron transfer within the EDA complexes induces the mesolytic cleavage of the halide ion and radical recombination of the arenes leading, after rearomatization and proton loss to C–C or C–S coupling products. Depending on the substitution pattern selective and unique cross-couplings are observed. UV and NMR measurements reveal the importance of the assembly for the photoinduced reaction. Enforced EDA aggregate formation in water allows new activation modes for organic photochemical synthesis.

The present study aims to remove the residual marbofloxacin (MBX) from milk with activated carbons (ACs) in batch and flow systems to meet the maximum residue limits (MRLs, 0.075 µg mL-1). Different types (granular and powder) and amounts of ACs were studied. In batch mode, 50 mg of commercial granular AC (CGAC) with 1083 m2 g-1 of BET specific surface area exhibited the superior adsorption performance for 20 mL of 1 µg mL-1 MBX-spiked milk. 93.7% of removal efficiency (RE) and 0.063 µg mL-1 of MBX residue were achieved. In flow mode, 325 mL of 1 µg mL-1 MBX-spiked milk was efficiently purified through 500 mg CGAC in a glass column (1 cm ID) and 93.4% of RE and 0.066 µg mL-1 of MBX residue were attained at the end. The flow process can handle 1.6 times higher in volume than that in batch mode. In conclusion, antibiotics can be efficiently, economically and conveniently removed using ACs adsorption from milk, despite the presence of competition adsorption of impurities. The adsorption with flow mode paves the way for the removal of antibiotics in milk.

Introduction. Understanding the biophysical phenomena related to the Hofmeister series or cosmotropic/chaotropic properties of ions requires experimental data on specific ion effects of large organic molecules.Problem Statement. Specific ion effects are of significant importance for biophysics and medicine. It is interesting to find out if additives with biologically relevant anions can interact with proteins and avoid aggregation.Purpose. The purpose of this research is to study the stabilizing/destabilizing effects in Poly(N-isopropylacrylamide) (PNIPAM)/water, hen egg white/water systems under influence of substances of various classes of different hydrophobia.Materials and Methods. Materials: sodium salts: salicylate, ferulate, benzoate, vanillate, cinnamate; humic acid sodium salt, hydroxy-sodium benzoate, glycine, L-alanine, sodium L-glutamate, D-(—)-quinnic acid, PNIPAM, egg white. Methods: measurement of the transition temperature (TT) of PNIPAM/water and the denaturationtemperature of the egg white / water systems.Results. Ion-specific effects have been studied with the use of models based on the research of the transition temperature (TT) evolution of binary PNIPAM / water mixtures (for heating from 0 to 35°C) and the denaturation temperature of the egg white / water (for heating from 48 to 65°C). The dependences of these temperatureson the content of substances that occur in live nature have been received at pH = 7.4.Conclusions. The results have shown the tendencies of the additive solubilizing effects on PNIPAM and egg white. The majority of substances studied has the salting-out effect on PNIPAM / water in the order NaBz ~ NaCinn < L-NaGlu ~ NaFer. For NaSal and NaHum; the salting-in effect has been established. For the egg white, all additives show the salting-in effect. In PNIPAM and egg white systems, NaBz and L-NaGlu demonstrate the opposite effects. The results have been compared with the ones for binary mixtures of water/di-propylene glycolpropyl ether (DPnP).

We introduce a simple way to liquify rare earth metals (REM) by incorporating the corresponding cations, in particular Eu3+, La3+, and Y3+, into polyvalent ionic liquids (ILs). In contrast to conventional methods, this is achieved not by transforming them into anionic complexes, but by keeping them as bare cations and combining them with convenient, cheap and commercially available anions (A) in the form [REM3+][A−]3. To do so, we follow the COncept of Melting Point Lowering due to EThoxylation (COMPLET) with alkyl polyethylene oxide carboxylates as anions. We provide basic properties, such as glass transition temperatures, viscosities, electrical conductivities, as well as water-octanol partition constants P and show that these ILs have remarkably different properties, despite the similarity of their cations. In addition, we show that the ionic liquids possess interesting luminescent properties as non-conventional fluorophores.

Infraspecific taxa (subspecies, races and varieties) are often seen as real entities in nature and recognized as biologically meaningful groups. But because infraspecific taxa by definition are subdivisions of species, their status depends entirely on the status of ‘their’ species. This makes the status of infraspecific taxa crucially dependent on the way species are considered and thus on the various species concepts that have been advanced as answers to the ‘species problem’. Accordingly, there is a profound lack of clarity regarding the following questions. What are infraspecific taxa? What is their biological meaning? Are they real entities or merely instrumental units? When should an infraspecific group be ranked and named as an infraspecific taxon? In this paper, we aim to contribute to greater clarity about these issues by examining which types of infraspecific groups are biologically meaningful in light of the main results from the species debate.

Since many decades, gamma-valerolactone (GVL) is known to be an excellent solvent, which, today, can be made of sustainable materials. Although numerous publications praise it as very green and versatile, GVL has never reached the level of a large-scale industrial product. Even relevant toxicity and biodegradability data are missing. In this paper, we present such data. Further, we make a detailed study, based on Hansen solubility parameters (HSP) and COSMO-RS calculations to identify harmful solvents that could be potentially replaced by GVL and to propose a variety of further applications of this substance. Toxicity tests with aquatic plants, bacteria, invertebrates, and a vertebrate cell line indicated a low acute toxicity of GVL towards aquatic organisms. Additionally, GVL was shown to be readily biodegradable, which further strengthens its potential as a “green” solvent. Accurate HSP of GVL were proposed and used in addition to COSMO-RS calculations to compare its solvent properties with the ones of classical, organic solvents. A similarity of GVL with several aprotic, highly dipolar solvents, such as the reprotoxic compounds N-methyl-2-pyrrolidone (NMP) and dimethylformamide (DMF), was found. Based on the results, GVL was concluded to be of interest as a green solvent in the manufacture of certain polymers or pharmaceuticals, as a cleaning agent in various paint and coating formulations, as well as a solubiliser in cosmetics, pharmaceuticals, or agrochemicals. Together with a very significant drop of its price, because of an intended large-scale production in Europe, the presented data should hopefully lead to the boost in applications that this green solvent deserves.

International audience; We use the model system ethanol–dodecane to demonstrate that giant critical fluctuations induced by easily accessible weak centrifugal fields as low as 2000g can be observed above the miscibility gap of a binary liquid mixture. Moreover, several degrees above the phase transition, i.e. in the one-phase region, strong gradients of ethanol concentration occur upon centrifugation. In this case, the standard interpretation of sedimentation equilibrium in the analytical ultracentrifuge (AUC) yields an apparent molar mass of ethanol three orders of magnitude higher than the real value. Notably, these composition gradients have no influence on the distribution gradient of solutes such as dyes like Nile red. The thick opaque interphase formed upon centrifugation does not appear as the commonly observed sharp meniscus, but as a turbidity zone, similar to critical opalescence. This layer is a few millimeters thick and separates two fluids with low compositional gradients. All these effects can be qualitatively understood and explained using the Flory–Huggins solution model coupled to classical density functional theory (DFT). In this domain hetero-phase fluctuations can be triggered by gravity even far from the critical point. Taking into account Jean Perrin's approach to external fields in colloids, a self-consistent definition of the Flory effective volume and an explicit calculation of the total free energy per unit volume is possible.

Amphiphilic molecules (e.g. hydrotropes) that enhance the solubility of hydrophobic compounds in water are often charged. As a result, such compounds also show specific ion effects. These effects can either strengthen or weaken the solubilisation power of amphiphilic molecules, depending on their degree of ion hydration. They can even prevail and transform an apparent solubilizer into an "anti-hydrotrope", i.e. a salting-out agent. In the present paper, we discuss this subtle balance between specific (Hofmeister) effects exerted by ionic headgroups and the hydrophobicity of the residual compound structure, including the size of the molecule and the presence of electron-withdrawing groups.

International audience; In the present work, meglumine, an aminocarbohydrate derived from glucose with a secondary amine group, was found to be able to increase the water-solubility of the well-known and beneficial flavonoid quercetin. pH proves to be a fundamental factor for this purpose. The solubility enhancement as a function of the pH as well as the mechanism behind this phenomenon were investigated. The state of charge of quercetin depending on pH has been estimated from the calculation of the pKa by COSMO-RS. A compromise between a satisfying solubility enhancement (6–7-fold) and reasonable stability against oxidation (70–75 % of quercetin still intact after 2 h) was found around pH 8. The solubilization mechanism is believed to be based on proton exchange between quercetin and the amine function of meglumine, and on the ability of meglumine to form numerous hydrogen bonds with water molecules through its five hydroxyl groups. Finally, it is shown that the underlying solubilization mechanism can be extended both to other polyphenols and to other hydrotropes.

The stability of proteins in solution poses a great challenge for both technical applications and molecular biology, including neurodegenerative diseases. In this work, a phosphorylated resveratrol material was examined for its anti-aggregation properties