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Background Melt crystallization is typically recognized as a high-efficient and green method for oil fractionation. This work concentrated on the novel layer melt crystallization for preparing desirable olein and stearin products from palm oil and the evaluation of fractions quality. Layer melt crystallization was performed at varied temperature parameters and their effects on fractions were evaluated by iodine value (IV), solid fat content (SFC) and melting point. The lipid composition, thermal and crystallization properties, and phase behaviors of the final optimized fractions were determined using Gas Chromatography (GC), high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (HPLC/APCI-MS) and Differential Scanning Calorimeter (DSC). Results Increasing crystallization tube temperatures under the same jacket temperature increased the melting point and SFC, while decreased the IV of the olein product. Opposite results were observed in stearin products. Major fatty acids in fractions were determined as palmitic acid and oleic acid. 1,2-Dioleoyl-3-palmitoyl-glycerol (POO) and 1,3-dipalmitoyl-2-oleoylglycerol (POP) were identified as the main triacylglycerols in olein and stearin fractions, respectively. Critical effect of crystallization temperature on co-crystallization of oleins and stearins was revealed. A transition from plate-like crystal growth to spherulitic growth with spontaneous nucleation was indicated in palm oil and stearin fractions with increasing crystallization temperature. As for olein fractions, the temperature increase resulted in heterogeneous nucleation from instantaneous nucleation. Conclusion In this study, novel layer melt crystallization was successfully applied and optimized for fractionating the palm oil. The composition and property changes of obtained fractions were analyzed and explained from both macro and micro levels. This article is protected by copyright. All rights reserved.

Background Ziziphus jujuba Miller cv. Dongzao is extremely susceptible to reddening, browning, nutritional loss, and perishability after harvest. In this study, we evaluated the mechanisms of calcium chloride and chitosan/nano-silica composite film treatments on the quality, especially in reddening, by physiological and metabolomic assays. Results The treatment delayed the decline of phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), and chalcone isomerase (CHI) activities. Meanwhile, the treated groups retarded the increases in anthocyanin and quercetin contents by inhibiting the gene expressions of flavonol synthase (ZjFLS), dihydroflavonol 4-reductase (ZjDFR), and anthocyanidin synthase (ZjANS), while promoting leucoanthocyanidin reductase (ZjLAR) expression, which leads to retardation of fruit reddening. Anthocyanins were found to be responsible for post-harvest winter jujube reddening through principal component analysis. Results from the technique for order preference by similarity to an ideal solution indicated that the treated group delayed the decline of the quality of 'Dongzao' and extended its shelf life. Conclusion The treatment induced the heightening of flavonoids metabolism. They enhanced the nutritional value and the ability to resist stress by delaying the decline of PAL, CHS, and CHI activities. Meanwhile, the treated groups retarded the increase in anthocyanin and quercetin contents by inhibiting the gene expressions of ZjFLS, ZjDFR, and ZjANS and promoting ZjLAR expression, which leads to retardation of fruit reddening. Anthocyanins are responsible for post-harvest winter jujube reddening. Coating treatment effectively delayed the decline of winter jujube quality. © 2020 Society of Chemical Industry.

In this work, a microemulsion emitting fluorescence was fabricated as a potential oral delivery system for bioactive compounds. In simulated oral administration, the microemulsion was characterized for its microstructure by 1hydrogen-nuclear magnetic resonance (1H-NMR). Results showed that microemulsions not only have good resistance to oral and gastric phases, but also lay a solid foundation for the release of bioactive compounds in the intestine. Fluorescence stability tests showed that microemulsions exhibit a remarkable fluorescence intensity in the digestive environment, indicating feasibility as a label-free delivery carrier. Moreover, in vitro release tests of bioactive compounds confirmed that an α-linolenic acid (ALA)-loaded microemulsion mainly released in the intestine, thereby achieving the aim of controlling the release of bioactive compounds. These results suggest that the synthesized fluorescent microemulsion, combining the favorable features of nontoxicity, antidigestive stability, remarkable fluorescence intensity, and controllable release, can be regarded as a promising label-free delivery carrier for oral administration.

The dietary fiber in oats is mainly concentrated in the bran; however, the oat bran is mostly used for livestock and poultry feed and thus has a low utilization rate and low added value. In this study, insoluble dietary fiber (IDF) was extracted by a combination of α-amylase and neutral protease. The optimal extraction conditions of the IDF were obtained by response surface methodology. The material-to-water ratio was 1:12.1, the concentration of α-amylase was 1.85%, and the hydrolysis time was 39.14 min. After purifying the crude fiber with 4% sodium oxide (NaOH), 70 °C hot water, and anhydrous ethanol, the purity of dietary fiber exceeded 95%. X-ray diffraction analysis indicated that the IDF was predominantly amorphous. Scanning electron microscopy showed that the IDF surface exhibited a loose porous network structure. Fourier-transform infrared spectroscopy of the crude IDF showed characteristic absorption peaks at 3626, 2929, 1667, 1538, 1455, 1242, and 1048 cm−1, while the infrared spectrum of the purified IDF showed characteristic absorption peaks at 3401, 2924, 1744, 1643, 1418, and 1040 cm−1, which is consistent with the structure of cellulose polysaccharide. Differential scanning calorimetry analysis showed that there were three exothermic peaks at 270–310 °C, 320–350 °C, and 440–460 °C, which may represent the pyrolysis peaks of hemicellulose, cellulose, and lignin, respectively, indicating that the oat bran IDF had good thermal stability. The results indicate that the oat bran IDF can be used for the production of dietary fiber products and health-care products.

In this work, the effects of α-linolenic acid (ALA) loaded in oil-in-water (O/W) and water-in-oil-in-water (W/O/W) microemulsions on cell viability, lactic dehydrogenase (LDH) viability, and reactive oxygen species (ROS) levels were examined using Cell Counting Kit-8 (CCK-8), an LDH assay kit, and a fluorescence microscope, respectively. The CCK-8 assay demonstrated that ALA inhibited MDA-MB-231 human breast cancer cell proliferation in a dose-dependent manner. Further, the results of LDH activity and ROS levels revealed that ALA-induced cancer cell damage was closely related to oxidative stress. Under the irradiation of ultraviolet light, the microemulsion without any added fluorescent dye would emit bright blue fluorescence, and the fluorescent images of the cells treated with ALA-loaded O/W and W/O/W microemulsions at different incubation times were taken, which exhibited long-term photostability and biocompatibility. In addition, the fluorescence mechanism of the microemulsion was explained by immobilizing surfactant molecules with aggregation-induced emission (AIE) properties at the water-oil interface through the microemulsion with a self-assembled structure. These findings showed the potential application of O/W and W/O/W microemulsions as the label-free delivery carriers in long-term imaging of living cells and real-time release monitoring of nutrients.

The crystallization and melting behaviors of binary tripalmitoylglycerol (PPP)/1,2-dioleoyl-3-palmitoyl glycerol (POO), tripalmitoylglycerol (PPP)/1,3-dipalmitoyl-2-oleoyl glycerol (POP), and 1,3-d...

The binding domains of lysozyme with ionic liquids (ILs, [C4mim]BF4, [C4mim]Cl, [C4mim]Br and [dmim]I) in aqueous solution was investigated by studying molecular interactions using spectroscopic techniques. Ultraviolet spectroscopy (UV) showed that the addition of ILs increased the absorption peak intensity of lysozyme at 210 nm by enhancing peptide bond valence electron transition. It is also found that a weak interaction between ILs and lysozyme chromophore groups was generated by analyzing the changes of absorption peak intensity near 280 nm. Fluorescence and Synchronous Fluorescence spectra results showed that four ILs had quenching effect on the fluorescent substances of lysozyme, and the quenching effect rose with increasing ILs concentration. Meanwhile, the interaction between lysozyme and ILs molecules is mainly based on Van der Waals force and two Tryptophan (Trp) residues (Trp62 or Trp108) at the active site of lysozyme molecules play a critical role in binding ILs to their own molecules.

α-Linolenic acid (ALA)-loaded microemulsion (ME) was prepared from isoamyl acetate, polyoxyethylene ether 35 (EL-35), ethanol and water. The dynamic phase behaviour was simulated using dissipative particle dynamics (DPD), which showed that spherical ME was formed at water/oil ratios of 1:9 and 9:1, while a lamellar structure with distinctive water-course and oil layer appeared at ratios of 3:7, 5:5, and 7:3. Phase stabilizing and anti-oxidation effect of environmental stresses on ALA-loaded microemulsion were investigated. Results showed that the ME region was large and had good environmental tolerance. Subsequently, the investigation of anti-oxidation stability revealed that more than 60% ALA of ALA-loaded ME could be protected from oxidation under environmental stresses. Furthermore, ALA-loaded ME was applied in aqueous-based foods. The transparency, precipitate, stratification and phase separation were used to evaluate influence of ME on product properties, confirming great feasibility and stability of ALA-loaded ME for practical applications.

Various active ingredients play a crucial role in providing and supplementing the nutritional requirements of organisms. In this work, we attempted to chemically manipulate the interfacial microstructure of oil–water microemulsions (ME) with carbon dots (CDs), concentrating on substantially enhancing the antioxidant capacity of α-linolenic acid (ALA). To this end, CDs were synthesized and introduced into an ME. The molecular interaction of surfactant with CDs was investigated by Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). The microstructure of the ME was monitored by transmission electron microscopy (TEM) and cryo-electron microscopy (cryo-EM). The cryo-EM result showed the oil–water interface in the ME was better defined after the CDs were loaded, and 1H NMR proved the CDs were distributed mainly at the interface. On the basis of these results, interfacial models were proposed. Final evaluation results demonstrated the stabilizing effect and oxidation-inhibition a...

Salt-dependent polymorphic control of glycine was investigated by using the microdroplet technique in this work. Sodium chloride (NaCl) was chosen as the additive to probe the influence of inorganic ions on the polymorphic nucleation of glycine. The thermodynamics and nucleation kinetics of glycine polymorphs in microdroplets were systematically analyzed based on the microdroplet technique. The crystal structures of the polymorphs were confirmed by powder X-ray diffraction (PXRD). The results illustrate that the critical concentration of NaCl required to induce the pure γ-form in the microdroplets is lower than that in the conventional method, which means that the microdroplet technique is more sensitive for the control of polymorph nucleation. The polymorphic nucleation selectivity of glycine was then discussed in view of classical nucleation theory. The results demonstrate that NaCl reduces the nucleation energy barrier of the γ-form of glycine, and for the same form of glycine, crystallization by the conventional method has a higher interfacial tension than in microdroplets.

Manipulating crystallization for macromolecule using ionic liquids (ILs) as an additive has received great attention, but how ILs accurately control their formation and crystallization pathway remains unclear. Here, we aim to illuminate the role of ILs on the solution chemistry of macromolecules by investigating their effects on the crystallization of lysozyme. The solubility findings show ILs changed intermolecular contacts, leading to lysozyme supramolecular repulsive interactions being induced or attractive interactions enhanced. Lysozyme was crystallized in the form of tetragonal crystals in the presence of [C4mim]BF4 (1-butyl-3-methylimidazolium tetrafluoroborate), [C4mim]Cl (1-butyl-3-methylimidazolium chloride) and [C4mim]Br (1-butyl-3-methylimidazolium bromide), while it was crystallized in the form of monoclinic crystals in the presence of [dmim]I (1,3-dimethylimidazolium iodine). Compared with that in the absence of ILs, lysozyme in the presence of [C4mim]Cl and [dmim]I contained a decreased α-helix content, but increased β-sheet content. The presence of [dmim]I also caused the β-turn content to increase and random coil content to decrease. This demonstration shows the formation of crystal nucleus is involved in transition at the protein secondary structure level, which may contribute to a better understanding of the role of ILs in the crystallization of bio-macromolecular materials and to developing a strategy to produce new bio-macromolecular materials using ILs.

Peony (Paeonia suffruticosa Andr.) seed oil (PSO) is considered as a new edible oil resource in China, which is rich in α-linolenic acid (ALA). Saponification reaction of PSO was the first step to improve comprehensive utilization of PSO. In this work, Box–Behnken design (BBD) and response surface methodology (RSM) were adopted to optimize the three main influencing factors of dosage of NaOH, reaction time and reaction temperature. The optimized yield (93.6 %) was recorded with the following conditions: 5.5 g of NaOH, 1.6 h of reaction time, and 57 °C of reaction temperature (for 20 g PSO). The model can be successful in predicting the highest yield within the range of experimental variables. By combining elementary reaction principle and the Arrhenius equation, the activation energy (88.473 KJ/mol), the pre-exponential factor (2.763 × 1014 m3/kmol∙min), and the kinetic equation of the PSO saponification reaction were obtained. This work not only enhanced the yield and reduced the raw material consumption of PSO saponification reaction, but also unveiled the equational relationship among reaction rate, reaction time and reactant concentration, which can be useful in industrial production of PSO fatty acid products.

In this study, oil-in-water microemulsions (MEs) were developed and used as a stable carrier for delivery of Paeonia ostii seed oil (PSO), a fatty acid mixture (FAM), and α-linolenic acid (ALA). Dynamic light scattering (DLS) was used to measure the particle size and polydispersity index (PDI) of the ME. The effects of temperature, exposure to light, and the addition of antioxidants on the peroxide values of the loads were investigated. The MEs were composed of droplets with diameters between 15 and 35 nm and PDIs lower than 0.5, and the addition of antioxidants had no significant effect on the particle size and dispersibility. Temperature, more than light, was the factor that most significantly promoted doxidation, and the influence of the addition of different antioxidants was higher by butylated hydroxytoluene (BHT), followed by vitamin C and vitamin E. Viability and morphology of A549 human lung adenocarcinoma cells treated with MEs were studied. The three evaluated MEs caused damage to cell membrane and inhibited the growth of cancer cells in a dose-dependent manner. Data on intracellular malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in cancer cells indicated that the treatment with MEs stimulated oxidative stress response and induced oxidative damage. These findings showed the latent capacity of MEs for protection of nutritional factors and for drug delivery.

In this study, oil-in-water (O/W) and water-in-oil-in-water (W/O/W) microemulsions (MEs) were synthesized as the carrier for curcumin delivery as a means to improve water solubility and antioxidative stability. MEs were characterized by measuring particle size, polydispersity index (PDI), transmission electron microscope, viscosity, and electrical conductivity. Furthermore, the position of curcumin in MEs was probed by proton nuclear magnetic resonance spectroscopy (1H NMR), and MEs antioxidant capacity and in vitro release of curcumin were investigated. Curcumin-loaded MEs were constituted of spherical droplets with a mean particle size of 10.0–20.0 nm and PDI of 0.2–0.3. 1H NMR confirmed that curcumin is embedded in the inner structure of MEs. Collectively, MEs synthesized in this study were shown to extremely improve solubility of curcumin. Furthermore, assessment of in vitro release and storage stability of the two experimentally-synthesized MEs showed that W/O/W ME had greater sustained release and antioxidant activity compared to O/W ME. No significant differences between storage at 4 °C and 25 °C were observed for the two evaluated ME. Our work illustrated that O/W and W/O/W MEs were well qualified for the delivery of curcumin.

The fractionation of oils has received considerable research attention, aiming at the modification of the properties of oils. The thermal and crystallization properties of palm kernel oil (PKO) and...

Kudzu starch was cross-linked with sodium trimetaphosphate (STMP) at different temperatures, time and of STMP concentrations in this work. The cross-linked starches (CLSs) were fractionated further into cross-linked amylose and amylopectin in order to compare the effect of cross-linking on the microstructure. According to scanning electron microscope (SEM), CLSs displayed the resemble appearance of spherical and polygonal shapes like NS. X-ray diffraction (XRD) revealed that amylose of native starch (A), NS and CLS displayed a combination of A-type and B-type structure, while that was not found in amylose of cross-linked starch (CLA). The deconvoluted fourier transform infrared (FT-IR) indicated that crystal structure of kudzu starch was losing with the proceeding of cross-linking reaction. The CLSs exhibited a higher retrogradation and freeze-thaw stability than NS. This was accompanied by a significant decrease in sedimentation, transparency, swelling power and solubility.

The applications of α-linolenic acid (ALA) in the food industry are restricted due to its poor water solubility and antioxidant stability. This study concentrates on developing an ALA-loaded microemulsion (ALA-ME) to enhance its solubility and antioxidant capacity. The formulation of the microemulsion was investigated based on pseudoternary phase diagrams. The ALA-ME was characterized by using electrical conductivity, viscosity and transmission electron microscopy (TEM). The microstructure of the ALA-ME was probed using nuclear magnetic resonance (1H-NMR). The results proved that ALA-ME consisted of spheroidal droplets with 20-40 nm diameter. A structural transformation from water in oil (W/O) to oil in water (O/W) occurred, as seen from the electrical conductivity determination. The 1H-NMR results revealed a transition of the ALA position encapsulated from the core area of the microemulsion to the lipophilic layer of the surfactant. Furthermore, two microstructural models of ALA-ME were proposed. The antioxidant evaluation demonstrated that the ALA antioxidant capacity in microemulsions was enhanced to about 80% compared with that of ALA in oil solution.

In this work, a one-step and two-phase solvothermal approach has been employed to synthesize Pt@C–O composite spheres formed by platinum (Pt) nanoparticles (NPs) anchored on oxygen-functionalized carbon spheres. The introduction of platinum(II) 2,4-pentanedionate (Pt(acac)2), benzoic acid, and chloromethane–glycerol two-phase solution is found to be significant for the formation of Pt@C–O composite nanostructures. Furthermore, the as-obtained Pt@C–O composites are found to have much more oxidized species of carbon (C–O) and platinum (Pt–O), as compared to commercial Pt/C. Results show that the Pt@C–O (CHCl3) catalyst based on the obtained Pt@C–O in a chloroform–glycerol mixture exhibits optimal electrocatalytic activity and superior carbon monoxide (CO) tolerance, which is mainly because the oxidation states of carbon and platinum cause the catalyst to regenerate during the methanol oxidation and CO anti-poisoning processes.

In this work, the effects of curcumin on the viability, morphology, and nanomechanics of SH-SY5Y neuronal cells were investigated using a conventional cell viability test kit (CCK-8) and sophisticated AFM imaging and force measurement techniques. CCK-8 tests show that SH-SY5Y neuronal cells have a dose-response to curcumin in terms of viability that is dependent on the exposure durations. When exposed to a maximum dosage of 32 μg/mL used in the present study for 4 h, 24 h, and 48 h, the cell viability dropped to 73.4 ± 4.5%, 9.1 ± 3.2%, and 2.5 ± 1.2% of the control, correspondingly. AFM studies show that curcumin can induce the disappearance of synapses of the cells and the change of biomechanics. After exposure for 24 h at the concentration of 16 μg/mL, the viscous deformation of the cells decreased from 2.15 ± 0.02 to 1.58 ± 0.03 (×10-15 N·m), the elastic deformation increased from 1.26 ± 0.04 to 1.72 ± 0.07 (×10-15 N·m), and adhesion work decreased from 0.56 ± 0.07 to 0.39 ± 0.04 (×10-16 N·m). The morphological and mechanical changes obtained using AFM can be interpreted from optically observed cellular structural changes. The present study provides insights into the effects of curcumin on neuronal cells from both biological and biophysical aspects, which can help more comprehensively understand the interactions between curcumin and SH-SY5Y cells. The demonstrated techniques can be potentially used to assess the efficacy of bioactive constituents on cells or help screen drugs.

The melting crystallization is a crucial way to isolate unsaturated fatty acids from peony seed oil, mainly composed of oleic acid (OA), linoleic acid (LA), and α-linolenic acid (ALA). The solid-liquid phase behaviors of oleic/linoleic acid (OA-LA), oleic/α-linolenic acid (OA-ALA), and linoleic/α-linolenic acid (LA-ALA) binary systems at the cooling and melting stage were investigated by employing differential scanning calorimetry (DSC). The solid-liquid melting phase diagrams of the three binary systems were constructed by the thermal analysis and ideal liquidus lines simulated with thermodynamic models, which interpreted the eutectic behaviors, polymorphic transition, and intermolecular interaction in different binary systems. The eutectic behavior appeared in the OA-LA and OA-ALA binary systems at the OA concentration less than 40% and 20%, respectively, and in LA-ALA binary systems at any proportion. Based on the enthalpy of the three binary systems, the enthalpy plots and the melting Gibbs free energy were provided and predicted, respectively. This work provided insights into the separation of peony seed oil or other plants oil-based fatty acid mixtures, hence suggesting great potential for the optimization of crystallization technology.

Peony (Paeonia suffruticosa Andr.) seed oil (PSO) has been identified as novel resources of α-linolenic acid (ALA) in China. In this study, fatty acid mixture (FAM) and ALA were obtained during the extraction of ALA from PSO by freezing crystallization and column chromatography. The oil-in-water microemulsion (ME) was selected as the delivery system to strengthen the stability of unsaturated bonds and improve the solubility of those lipophilic fatty acids. The ME samples were characterized by particle size measurement, transmission electron microscope (TEM), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, and rheological measurement, and their stability was evaluated and compared by 60 days of storage and pasteurization heat treatment methods. The stability of the three ME samples was found to be ALA-ME > FAM-ME > PSO-ME due to the increased molecular weight and complex structure of the load. The ALA-ME system sustained a stable particle size (

For platinum (Pt) composite electrocatalysts formed by multiple components, the selective growth of Pt on oxygen-containing species can maximize the CO-resistance and durability, which is a big challenge in interfacial science. In this paper, Pt/TaON|N-rGO composite was obtained by an in-situ calcination of a layered supramolecule self-assembled by TaCl5, urea and n-butanol, followed with the targeted growth of Pt nanoparticles induced by the defects at the junction of TaON|N-rGO. As a result, Pt/TaON|N-rGO electrode with the ideal ternary interface of Pt|TaON|N-rGO exhibited exceptionally high catalytic mass activity (250.6 mA·mg−1Pt), excellent CO-tolerance (If/Ib = 1.6 normalized to Pt/C) and long-term durability (136.4 mA·mg−1Pt after continuous 1200 min operation) for EG oxidation in acid, compared to commercial Pt/C (57.8 mA·mg−1Pt). The promoted performance was attributed to the synergies at ternary interface of Pt|TaON|N-rGO, and the boosting CO-tolerance was achieved by the shortened L-H pathway ascribed to the selective growth of Pt nanoparticles on the heterojunction of TaON|N-rGO.

Pt based catalysts with multi-component is widely used to improve the electrocatalytic ability in alcohol oxidation, however, it is still big challenge to maximize the synergies of different component. Herein, Pt/N-rGO/Nb4N5 composites with multilayered structure were prepared, with nitrogen doped reduced graphene oxide (N-rGO) layer covered on Nb4N5 sheet and Pt nanoparticles selective loaded on the interface of Nb4N5 and N-rGO. Furthermore, N-rGO was confirmed to act as the connector between Pt and Nb4N5, ascribed to the Nb4N5–N-rGO-Pt bridge via N-doping of graphene and partial oxidation of Pt. By comparison, Pt/N-rGO/Nb4N5-10 composite showed the best distribution of N-doped rGO in the gap between Pt nanoparticles and Nb4Nb5 sheet, as the ratio of urea and NbCl5 was 10. Accordingly, Pt/N-rGO/Nb4N5-10 electrode exhibited the optimal catalytic activity and durability for multiple alcohol oxide in acid, such as methanol, ethanol, and ethylene glycol, since maximum ternary synergy was achieved by the stable multilayered structure, involving the highest ESCAs due to more exposed active sites of Pt nanoparticles, the best electrical conductivity ascribed to the incorporation of N-rGO, and excellent CO tolerance because of the efficient activation of water on Nb4N5 and N-rGO.

In this work, ALA-loaded water-in-oil-in-water (w/o/w) microemulsion was synthesized as a delivery carrier. A static digestion model in vitro (oral, gastric, and intestinal phases) was utilized to simulate the digestion process of ALA-loaded w/o/w microemulsion. The results of particle size distribution and transmission electron microscope (TEM) in vitro demonstrated that there was no distinct biochemical reaction in different digestive environments, which means w/o/w microemulsion was highly resistant to the digestive phase. Notably, it was observed that high bioavailability was showed mainly in gastric and intestinal for the overt release of ALA during the gastrointestinal digestion process in vitro. Subsequently, the interaction mechanism between w/o/w microemulsion and enzyme molecules in simulated digestion phases was illustrated. In vivo determination by IVIS Spectrum Live Imaging System of C-dots (CDs) loaded w/o/w-microemulsion was to track the metabolism and biodistribution in the nude mice. The live images which showed the metabolism and biodistribution of w/o/w microemulsion in vivo depicted that w/o/w microemulsion was completely assimilated after 12 h and was metabolized through renal and fecal excretions. No obvious abnormality was observed in the nude mice throughout the study. These promising results suggested that w/o/w microemulsion has a wide range of applications for the utilization of bioactive ingredients with high efficiency as a delivery carrier.

The solubility of ethenzamide in methanol, ethanol, 1-propanol, isobutanol, ethyl acetate and acetonitrile was determined via the gravimetric method in the temperature range from 288.15 K to 323.15 K at atmospheric pressure. Five thermodynamic models were employed to correlate the experimental solubility data. The correlated results were analyzed and compared with the experimental results. It was found that all the thermodynamic models give satisfactory correlation results, in which the modified Apelblat model shows the best fitting result. In addition, the molecular modeling studies were carried out to give the explanation for the sequence of solubility in various solvents. The dissolution enthalpy and entropy of ethenzamide were obtained by using the Van't Hoff equation. Furthermore, the mixing thermodynamic properties of ethenzamide, including the mixing Gibbs energy, the mixing enthalpy and entropy, as well as the infinite-dilution activity coefficient and the infinitesimal concentration reduced excess enthalpy, were also obtained by using the Wilson model and the experimental solubility values.

In this work, the solvent-mediated phase transformation of the metastable form (Form II) to the stable form (Form I) of ethenzamide–saccharin cocrystal in isopropanol was investigated. Solubility of Form I and Form II in pure isopropanol was also measured. The transformation mechanism from Form II to Form I was analyzed by some online and off-line tools including attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, Raman spectroscopy, and polarizing microscopy. The results demonstrate that the transformation process consists of three steps, involving the dissolution of Form II, the nucleation of Form I, and the following growth of Form I. The ATR-FTIR and Raman results show that the polymorphic transformation from Form II to Form I is controlled by the nucleation and growth of Form I. Furthermore, the microscope photographs clearly reveal that the Form I preferably nucleates and grows on the (100) surface of Form II. The molecular simulation results indicate that higher adsorpt...

The phase equilibrium for ethenzamide (EA) and saccharin (SAC) in ethanol, isopropanol and ethyl acetate were determined at 298.15 and 308.15 K under atmospheric pressure in this work. In ethanol and isopropanol, the two solutes dissolve incongruently and the diagrams are asymmetric, so excessive EA is required to isolate cocrystals. However in ethyl acetate, EA and SAC exhibit similar dissolution behavior, resulting in larger and more symmetric regions for EA-SAC cocrystal, which would be beneficial to enhance the control of EA-SAC cocrystallization process. In addition, the solubility of EA-SAC cocrystal was correlated by using a mathematical model based on both solubility product and solution complexation. The solubility of EA-SAC cocrystal as a function of SAC concentration was calculated. These new findings are of great importance to control the cocrystallization process of EA-SAC.

Platinum nanocrystals with different growth rates along 〈100〉 to 〈111〉 are selectively shaped using the reaction solvent, which is due to the different reduction rates in diverse reaction solutions. Electrocatalytic results show that the branched and cubic Pt/C catalysts exhibit much higher ECSA and enhanced activity of MOR, in addition, the branched Pt/C catalyst shows improved durability.

Carbonaceous nanospheres anchored with PtxNiyCoz alloy nanoparticles (PtxNiyCoz /CA) was obtained by a two-step hydrothermal approach. Multiple characterizations confirmed that oxygen functionalized groups on the surface of the carbonaceous sphere could deeply anchor the PtxNiyCoz alloy nanoparticles, which prevented the further growth of alloy particles and formed a stable interface between the alloy particle and carbonaceous supporter. Accordingly, as-prepared PtxNiyCoz/CA electrode exhibited superior electro-catalytic performance in multiple electrochemical reactions, including MOR, ORR, and OER, due to the optimal interfacial effect.

The effects of multi-scale molecules on physical properties, antioxidant capacity and in vitro release kinetics in the α-linolenic acid-loaded water-in-oil-in-water (W1/O/W2) microemulsion were revealed in this work. The glucose and carboxymethyl cellulose sodium (CMC) solutions were selected as the internal aqueous phase (W1) of the microemulsion, respectively, while the multi-scale molecules, such as sodium chloride (NaCl), glycine (Gly), glucose (Glu), CMC, bovine serum albumin (BSA) and sodium caseinate (SC), were added in the external aqueous phase (W2) to balance the osmotic pressure and meanwhile their effects on the fluorescence property, antioxidant capacity and release kinetics were probed. Among these, the CMCW1-NaClW2 and GluW1-CMCW2 microemulsion within the appropriate concentration range could dramatically increase the storage stability and antioxidant capacity by inhibiting the aggregation of droplets or Ostwald ripening, while the addition of Gly and SC had the negative effect on the stability of microemulsion. Finally, the release kinetic dates were fitted and the Korsmeyer-Peppas equation was considered as the most suitable to explain the ALA release kinetics that were controlled by diffusion and erosion in the simulated gastric fluid (SGF, pH = 2.0) and simulated intestinal fluid (SIF, pH = 6.8). The application of release kinetic models in nutrient nano-delivery systems could facilitate the investigation on the release mechanism of nutritional components.

Platinum (Pt) nanoassemblies with different morphologies, such as nanospheres self-assembled from nanoparticles, multipolyhedral nanostructures built with octahedral nanocrystals, hollow nanospheres consisting of armed nanoparticles, and two-dimensional arrays arranged by nanocubes, were synthesized by a solvothermal approach. The concentration gradient of Pt monomers plays a key role in the architecture of the self-assembled nanostructures, which is attributed to the weak dissolution of the Pt precursor in high-viscosity solvent. As a consequence, the electrode prepared from hollow Pt nanospheres consisting of armed nanoparticles shows much higher performance in the methanol electro-oxidation process than others. Meanwhile, the electrodes prepared from these novel Pt nanoassemblies exhibited long-term durability for methanol electro-oxidation, compared to the electrode prepared from monodispersed Pt nanoparticles.

Moxidectin is a single-component and semisynthetic macrocyclic lactone antibiotic, which has been widely used in the prevention and treatment of parasites in farm animals. In this paper, the transformation of ethanol solvate to form I of moxidectin in an ethanol–water mixture was studied. Offline methods and online instruments were used to monitor and identify the transformation process, and the influences of water content and temperature were discussed. It is noted that the transformation kinetics are highly sensitive to both the solvent composition and temperature and the transformation rate is a function of the ethanol content in aqueous ethanol mixtures. The solvent-mediated polymorphic transformation mechanism from ethanol solvate to form I was suggested, and the process is controlled by the nucleation and growth rate of the stable form. Understanding these effects can aid optimization and improve process control in the crystallization of moxidectin.

Nanoscale microemulsions have been utilized as delivery carriers for nutraceuticals and active biological drugs. Herein, we designed and synthesized a novel oil in water (O/W) fluorescent microemulsion based on isoamyl acetate, polyoxyethylene castor oil EL (CrEL), and water. The microemulsion emitted bright blue fluorescence, thus exhibiting its potential for active drug detection with label-free strategy. The microemulsion exhibited excitation-dependent emission and distinct red shift with longer excitation wavelengths. Lifetime and quantum yield of fluorescent microemulsion were 2.831 ns and 5.0%, respectively. An excellent fluorescent stability of the microemulsion was confirmed by altering pH, ionic strength, temperature, and time. Moreover, we proposed a probable mechanism of fluorochromic phenomenon, in connection with the aromatic ring structure of polyoxyethylene ether substituent in CrEL. Based on our findings, we concluded that this new fluorescent microemulsion is a promising drug carrier that can facilitate active drug detection with a label-free strategy. Although further research is required to understand the exact mechanism behind its fluorescence property, this work provided valuable guidance to develop new biosensors based on fluorescent microemulsion.

Xylitol is fast gaining ground over other sugar substitute owing to its high sweeting and low calorie properties. Menthol, a flavor agent, is widely used in food production. However, menthol can easily sublimate, while xylitol has a strong hygroscopicity. In this study, the co-crystals of xylitol with menthol are performed aiming to improve their negative properties. The results indicated that the water activity of co-crystals varies from 0.126 to 0.370. Meanwhile, the hygroscopicity of co-crystals is reduced to some extent compared with xylitol. Differential scanning calorimetry results demonstrated that co-crystals have similar thermal properties. What’s more, co-crystals have nearly identical X-ray diffraction patterns with xylitol. Thus, it is suggested that the microstructure of co-crystals is influenced mostly by the compound with a high ratio. Overall, this study can convey important idea for the development of food new materials, also the control and application based on co-crystallization techniques in food industry.

Ionic liquids (ILs) have biomaterial applications and are used for protein crystallization. The present study explores the thermal denaturation and degradation kinetics of the lysozyme crystals induced by IL [C4mim]Cl using differential scanning calorimetry (DSC). Lysozyme crystals were scanned from 10 to 250 °C at different heating rates varying from 5 to 20 °C min−1. Under the same heating rate, the addition of the IL makes lysozyme crystals confer more resistance to thermal denaturation and change values of conversion rate increase. The denaturation and degradation peak shifted towards higher temperature as heating rate increased and showed an activated denaturing kinetics of the lysozyme. It can be clearly noticed that the addition of the IL increases activation energy for denaturation and decreases it for degradation. The effect of the IL on thermal denaturation is attributed to the change of lysozyme–lysozyme molecular interaction. © 2014 Curtin University of Technology and John Wiley & Sons, Ltd.

Protein crystallization is a complex physical and chemical process. The high-quality protein crystal is still a persistent bottleneck to the application of X-ray crystallography in structural biology. The additives may promote formation of crystal nucleus and subsequent growth in protein crystallization. As a distinct material, ionic liquids (ILs) have aroused great attention and interest for protein crystallization due to their unique properties. We reviewed the progress of protein crystallization and reported research about protein crystal morphology control by ILs, as crystal growth template, in aqueous solutions. ILs encourage changes in some cases in terms of growth morphology and crystal size. The effect of ILs on lysozyme growth morphology can be attributed to changing interaction among lysozyme molecules in aqueous solutions. This work can provide some initial insight into the preparation of high quality crystal and the development of new crystal form.

Understanding the salting effects on the solubility and transformation kinetics of amino acid solvates in aqueous solutions is important for a rational design of the industrial isolation and purification conditions of amino acid. We report measurements of l-phenylalanine anhydrate and monohydrate solubility as a function of temperature in aqueous NaCl, KCl, Na2SO4, and (NH4)2SO4 solutions with concentrations of 4 g/100 g of H2O in this work. It is found that salts play an important role in determining solubility reduction and solvated behavior, which had not been elucidated. This comparison has provided important insight into the dependence of l-phenylalanine solvates on temperature. The dependence of the l-phenylalanine anhydrate/monohydrate transformation kinetics on temperature in the presence of NaCl, as a typical salt, is discussed. It is noted that NaCl can markedly increase the rate of the transformation of l-phenylalanine between anhydrate and monohydrate compared with pure water. A simple model f...

The solubility of N-chlorobenzenesulfonamide sodium and N-chloro-4-toluenesulfonamide sodium in ethanol + propan-2-ol solvent mixtures can be exactly measured by a laser technique at atmosphere pressure ranging from 278.00 K to 323.00 K. Then, using the combined binary solvent CNIBS/Redlich–Kister equation, the results of these measurements were correlated accurately. The experimental solubility and correlation equation in this work are of much value and widely used in the industrial purification process. Moreover, the thermodynamic properties of dissolution process were also calculated with the experimentally determined solubility data.

The solubility of xylitol in ethanol+water solvent mixtures was measured at temperatures ranging from 278.00 K to 323.00 K at atmospheric pressure by using a laser technique. The results of these measurements were correlated by the combined nearly ideal binary solvent CNIBS/Redlich-Kister equation. The experimental solubility and correlation equation in this work can be used as essential data and models in the purification process of xylitol. The variant 2 in the CNIBS/R-K models was confirmed to be more adaptable to predict solubility of xylitol in binary ethanol +water system. Using the experimentally measured solubilities, the thermodynamic properties of dissolution of xylitol, such as Gibbs energy, molar enthalpy of dissolution, and molar entropy of dissolution, were calculated.

Lysozyme crystals in the presence of 1-butyl-3-methylimidazolium tetrafluoroborate ([C(4)mim]BF(4)), 1-butyl-3-methylimidazolium chloride ([C(4)mim]Cl), 1-butyl-3-methylimidazolium bromide([C(4)mim]Br), and 1,3-dimethylimidazolium iodine([dmim]I) were prepared, and the influence of ionic liquids (ILs) on the structure and activity change of lysozyme was investigated. Fourier transform infrared spectroscopy revealed the major secondary structures of α-helix and β-sheet for lysozyme. It was interesting to note that increases of the band near 2,935 and 1,656 cm(-1) from Raman spectroscopy are attributed to the unfolding of lysozyme molecules. A shift in amide III from 1,230 to 1,270 cm(-1) in adding [dmim]I occurs, indicating a transformation from β-sheet to random coil. With regard to adding [C(4)mim]BF(4), [C(4)mim]Cl, and [C(4)mim]Br, α-helix and β-sheet are the predominant structures for lysozyme. The activity study showed that the ILs used brought a positive effect. Especially, [dmim]I leads to a drastic increase in relative activity, and its value reaches 50 %.

Research shows some potential applications for ionic liquids (ILs) with biomaterials. In this work, the ILs 1-butyl-3-methylimidazolium tetrafluoroborate ([C4mim]BF4), 1-butyl-3-methylimidazolium chloride ([C4mim]Cl), 1-butyl-3-methylimidazolium bromide ([C4mim]Br), and 1,3-dimethylimidazolium iodine ([dmim]I) were employed to investigate their effects on the solubility of lysozyme in aqueous solutions at pH 4.5. The results demonstrate that lysozyme solubility increases with the addition concentration of [C4mim]BF4 and [C4mimCl] and is nearly invariable with the increase of the [C4mim]Br concentration. Interestingly, the solubility slowly decreases with the increase of [dmim]I concentration. At constant added IL concentration, the solubility increases with increasing temperature. The effect of ILs on solubility can be attributed to changing interaction among lysozyme molecules. The effect of ILs employed in this work may provide crucial insight into the preparation of high-quality crystals and the develo...

Ionic liquids (ILs) exhibit a variety of properties that make them attractive additives for biomaterials. 1-Butyl-3-methylimidazolium tetrafluoroborate ([C(4)mim]BF(4)), 1-butyl-3-methylimidazolium chloride ([C(4)mim]Cl), 1-butyl-3-methylimidazolium bromide ([C(4)mim]Br), and 1,3-dimethylimidazolium iodine([bmim]I), as additives during lysozyme crystallization, were tested for their effects on the thermal stability and morphology of lysozyme crystals obtained. [C(4)mim]Cl was chosen to evaluate the effect of IL addition concentration on the thermal stability of lysozyme. It is shown that the characteristic peak temperature and endothermic enthalpy values (DeltaH) for denaturation increase with increasing addition concentration. As for the degradation, peak temperatures decrease, whereas endothermic enthalpy values markedly increase with the rise of [C(4)mim]Cl addition concentration. In the case of adding [C(4)mim]BF(4), [C(4)mim]Br, and [bmim]I, similar thermal behaviors of lysozyme crystals were observed. The effect of ILs on thermal behaviors of lysozyme can be attributed to enhancing crystal contacts, changing conformational stability, or interaction among molecules, as evidenced by difference in crystal growth morphology. This study is especially helpful in controlling the thermal stability of lysozyme crystals and in gaining initial insight into potential crystallization conditions for prescreening ILs that stabilize the protein and other macromolecule crystals.

Using a laser monitoring observation technique, the solubility of erythromycin acetone solvate in binary acetone + water solvent mixtures was measured by a synthetic method at temperatures ranging from 298.00 K to 323.00 K and at atmosphere pressure. The results of these measurements were correlated by the combined nearly ideal binary solvent CNIBS/Redlich–Kister equation and the modified Apelblat equation, respectively. For the solubility data studied, the CNIBS/Redlich–Kister equation was found to provide a more accurate mathematical representation of the experimental data.

The thermal, phase transition and spectral studies of erythromycin A dihydrate and acetone solvate were performed by Differential Scanning calorimetry (DSC), Thermo Gravimetry (TG-DTA), X-Ray Powder Diffraction (XRPD) and Fourier Transform Infra-Red (FTIR) spectrum. The non-thermal kinetic analysis of erythromycin A dihydrate was carried out by DSC at different heating rates in dynamic nitrogen atmosphere. The result showed that heating rate has substantial influence on the thermal behavior of erythromycin dihydrate. The Arrhenius parameters were estimated according to the Kissinger method. Corresponding to dehydration of dihydrate, melting of dehydrated dihydrate, phase transition from dehydrated dihydrate to anhydrate, and melting of anhydrate, the calculated activation energy were 39.60, 269.85, 261.23, and 582.16 kJmol–1, the pre-exponential factors were 3.46 × 103, 8.06 × 1032, 9.23 × 1030, and 7.29 × 1063 s–1, respectively. Ozawa method was used to compare activation energy values calculated by Kissinger method. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The application of in situ FBRM and PVM in monitoring the erythromycin dilution crystallization process and the transformation of erythromycin solvates is introduced. Influences of seeding strategies on nucleation and growth were examined in acetone aqueous solutions. It is noted by FBRM monitoring that the dominant chord length of crystal products is dependent on the supersaturation when seed crystals are added. Higher supersaturation leads to a smaller dominant chord length. In the crystallization process, breakage and agglomeration are not determined, and secondary nucleation mainly originates from induced nucleation by local high supersaturation resulting from water addition. The transformation process from metastable erythromycin acetone solvate to stable dihydrate was successfully monitored in pure water by using both PVM and FBRM, and the transformation mechanism can be identified as mediated-solution phase transformation. PVM is proven to be more appropriate to monitor transformation between eryth...

The solubility of erythromycin A dihydrate in pure ethanol, propan-2-ol, methanol, acetone, chloroform, and acetone + water was measured by a synthetic method at temperature ranging from 293.20 K to 323.00 K at atmosphere pressure. The laser monitoring observation technique was used to determine the disappearance of the solid phase in a solid + liquid mixture. The results of these measurements were correlated by a semiempirical Apelblat equation.

The effect of five different impurities, the cations Al3+, Fe2+, and Mg2+ and the anions SO42- and Cl-, on the metastable zone width of phosphoric acid hemihydrate has been investigated using a laser method with a linear cooling rate. The metastable zone width was measured as a function of impurity concentration and cooling rate in the seeded system. The influences of impurity ions on the metastable zone width of phosphoric acid hemihydrate take place by different mechanisms. Mg2+ has enlargement effects on the metastable zone width, whereas Al3+ and Fe2+ have both enlargement or suppression effects under different impurity concentrations. Cl- and SO42- have relative weak effects on the metastable zone width.