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The influence of high pressure processing (HPP) and polysaccharides on the structure and emulsifying properties of lactoferrin (LF) has been investigated by fluorescence, circular dichroism, FTIR, dynamic light scattering, physical stability, confocal laser scanning microscopy, and microrheology measurements. Compared with LF alone, the presence of xanthan gum (XG) inhibited the exposure of hydrophobic core in LF caused by HPP to a certain extent. HPP slightly changed the secondary structure of LF, while the addition of XG expanded the effect. 200 MPa treatment was favorable for LF-XG complexes to form ordered structure, while higher pressure decreased the content of α-helix. HPP treatment or XG addition both led LF molecules to unfold, while the combination of them caused LF to fold under certain conditions. Droplet sizes of LF-XG stabilized emulsions were smallest under 400 MPa. HPP increased the charges on the surface of droplets. HPP caused the oil droplets closer to spherical, more evenly distributed and reduced the flocculation among droplets. The Addition of 0.3 wt% XG or combination of 0.2 wt% XG and HPP could maximize the physical stability of emulsions. By altering the molecular structure of LF or LF-XG, HPP, and XG increased the viscoelasticity of emulsions. [ABSTRACT FROM AUTHOR]

High-precision pre-alignment of a magnet is a crucial step in the construction of a particle accelerator such as the Hefei Advanced Light Facility (HALF) or High Energy Photon Source (HEPS). To improve the accuracy and efficiency of pre-alignment, there are plans to build a four-station laser tracker multilateration measurement system (FLTMMS) at HALF. In the coordinate conversion and self-calibration processes of a FLTMMS, an unreasonable distribution of common points can lead to a loss of accuracy. A method for selecting common points based on uniformity in the FLTMMS is therefore proposed. In this method, the coordinate transformation space is divided according to the uniformity in different directions. The feasibility of our method is compared and analysed through coordinate conversion and self-calibration experiments. Simulations show that with the same number of common points, this method leads to higher accuracy in coordinate conversion and self-calibration. The proposed method compensates for the loss of accuracy due to aggregation of common points. Comparative analyses show a clear positive relationship between the accuracy improvement effect and the difference in uniformity. The distribution of common points will change the accuracy distribution of FLTMMS. Our approach of providing essential references for pre-aligning HALF magnets has been applied to HEPS with extensive engineering experience, to verify the practicality of this method for engineering applications. In the actual measurements, self-calibration is performed using an edge measurement network, and coordinate conversion is conducted using angle measurements. Based on actual measurements, the self-calibration accuracy is 1.7 μm and a conversion accuracy is 14.8 μm. The results show that under the premise of satisfying precision, the method can reduce the number of common points, thus decreasing the cost of common points construction. Our study provides instructions for pre-alignment at HALF in the future. [ABSTRACT FROM AUTHOR]

In this study, development of icaritin-loaded liposomes stabilized by four kinds of surfactants (i.e. Span40, Span20, Sucrose ester and Tween80, with the hydrophile lipophile balance (HLB) numbers of 6, 8, 9 and 16, respectively) was presented, which tackled the poor solubility and low physicochemical stability of icaritin in the aqueous phase. The addition of icaritin and cholesterols into the bilayers exhibited an increase in the average diameter and high encapsulation efficiency, regardless of the variety of surfactants. Meanwhile, when cholesterols were absent, surfactants with low HLB numbers (≤9) produced liposomes with higher average sizes (nearby 200 nm) and zeta-potentials (−20 to −35 mV) than Tween80. DPPH and ABTS + free radical-scavenging experiment exhibited different activities due to the diverse profiles of the free radicals, where their polarity and solubility must be taken into account. Physicochemical stability results revealed that Sucrose ester and Tween80 liposomal systems had the best physical and thermal stability, respectively. In addition, UV–vis absorption spectra and FTIR analysis confirmed that the formation of hydrogen bonds promoted the embedding effects of icaritin. Last but not the least, in vitro digestion experiment demonstrated that those liposomes containing Sucrose ester and Tween80 had the highest release levels, up to 75.68 ± 0.25% and 77.23 ± 0.58%, respectively. Therefore, these results suggested that the surfactants selection could be promising strategy for manufacturing different functional liposomal foods with different bioactive substance under various storage conditions. [ABSTRACT FROM AUTHOR]

Interfacial protein–polysaccharide complexes can be utilized in emulsion-based delivery system and contained functional component or medical ingredient. In the present work, the interaction of lactoferrin (LF, 0.2 wt%) with beet pectin (BP, 0–0.15 wt%) was researched in aqueous solutions at different pH (2–9) and ionic strength (0–800 mM) to provide the information about properties of complexes. A simulative environment was created to explore the optimal concentration of BP to formulate LF-coated stabilized emulsion and how the emulsion responded to the changing environmental pH (2–9) and ionic strength (0–500 mM). Particle size, particle distribution index, zeta-potential, turbidity, Turbiscan stability index,, and peak thickness were used to characterize the physical stability of emulsions. The confocal laser scanning microscopy was used to derive the microscopy images of droplets. The results indicated that 0.4 wt% was the optimal concentration to formulate emulsions, and the LF-BP-coated bilayer emulsion has a preferable stability in more extensive range than the pure LF-stabilized emulsions under the environmental stresses through electrostatic interactions. The results of this study will play an important role in facilitating the utilization of LF-BP complexes as an emulsifier in the development of incorporating functional component or medical ingredient into commercial products. [ABSTRACT FROM PUBLISHER]

A simple and efficient HPLC fingerprint method was developed and validated for quality control of the polyphenols extracted from pomegranate peel (PPPs). Ten batches of pomegranate collected from different orchards in Shaanxi Lintong of China were used to establish the fingerprint. For the fingerprint analysis, 15 characteristic peaks were selected to evaluate the similarities of 10 batches of the PPPs. The similarities of the PPPs samples were all more than 0.968, indicating that the samples from different areas of Lintong were consistent. Additionally, simultaneous quantification of eight monophenols (including gallic acid, punicalagin, catechin, chlorogenic acid, caffeic acid, epicatechin, rutin, and ellagic acid) in the PPPs was conducted to interpret the consistency of the quality test. The results demonstrated that the HPLC fingerprint as a characteristic distinguishing method combining similarity evaluation and quantitative analysis can be successfully used to assess the quality and to identify the authenticity of the PPPs. [ABSTRACT FROM AUTHOR]

A simple and reliable HPLC fingerprint method was developed and validated for the quality control and identification of Ziyang green tea. Ten batches of Ziyang green tea collected from different plantations in Shaanxi Ziyang of China were used to establish the fingerprint. The feasibility and advantages of the used HPLC fingerprint were verified for its similarity evaluation by systematically comparing chromatograms with professional analytical software recommended by State Food and Drug Administration (SFDA) of China. The similarities of the fingerprints of 10 batches of tea samples were all more than 0.981. Additionally, simultaneous quantification of 10 major bioactive ingredients in the tea samples was conducted to interpret the consistency of the quality test. The results indicated that the HPLC fingerprint as a characteristic distinguishing method combining similarity evaluation and quantification analysis can be successfully used to assess the quality and to identify the authenticity of Ziyang green tea. [ABSTRACT FROM AUTHOR]

As a fourth-generation light source based on a diffraction-limited storage ring, Hefei Advanced Light Facility (HALF) has higher requirements for the alignment of magnets in terms of accuracy, efficiency and reliability. In this paper, we propose a system called the Reference Network of Alignment (RNA) that can achieve a transverse alignment accuracy of the magnets of ± 20 μ m along a 100 m straight section of the accelerator. We first present the concept underlying the design of the RNA system. The girder assembly on which several common axis magnets are fixed forms the independent unit, and a long stretched wire is used as a straightness reference. A theoretical analysis of our system is then presented based on strict mathematical models that center on the combining method of the wire position sensors, the hydrostatic leveling sensors, and two-axis inclination sensors, for which the positions and orientations are known relative to each other. Finally, we perform a simulation of the RNA system using the Monte Carlo method. The results show that it is credible to assume that the RNA system can achieve an alignment installation accuracy of 20 μ m and a displacement monitoring accuracy of 15 μ m. [ABSTRACT FROM AUTHOR]

High pressure processing (HPP) is an emerging non-thermal processing technology and a preparation method to induce protein-polysaccharide mixed gels, which can encapsulate and delivery thermosensitive bioactive compounds. This study investigated the properties of β-lactoglobulin (β-Lg)/κ-carrageenan (κ-car) mixed gels induced by HPP (0.1–600 MPa for 30 min, 25 °C) with different ratios of β-Lg to κ-car at pH 3.0, 5.0 and 7.0. The results showed that the pressure required to form β-Lg/κ-car mixed gels was at least 400 MPa when the β-Lg/κ-car mass ratio increased to 14:1 at all tested pH values. The water holding capacity and textural properties increased with the increase of pressure levels. The hydrophobic interaction was dominant in the mixed gels induced by HPP at all pH values, and the network structure was more compact and smoother with higher pressure. • It can form mixed gels by HPP directly at β-Lg: κ-car≥8: 1 (P = 600 MPa for 30 min). • HPP can improve gel strength, WHC and textural properties of β-Lg/κ-car mixed gels. • The hydrophobic interaction was dominant in the mixed gels. • The network structure was more compact and smoother with higher pressure. [ABSTRACT FROM AUTHOR]

• The incorporation of β-sitosterol improved the encapsulation of curcumin. • Stability was improved when β-sitosterol was inserted into curcumin liposomes. • First-order model was fit for curcumin release from β-sitosterol liposomes. • The more β-sitosterol slowed the release of curcumin from liposomes better. • Bioavailability of curcumin was improved for β-sitosterol liposomes. In this work, the effect of β-sitosterol (Sito) on vesicle characteristics, physicochemical stability as well as the in vitro release and bioavailability of curcumin-loaded liposomes (Cur-LP) was studied. When 20–33 mol% of Sito was incorporated, encapsulation efficiency of curcumin was improved due to the high amount of liquid-ordered domains in membranes. At 50 mol% Sito a lower encapsulation efficiency was observed possibly due to membrane defects. The physical, thermal and photo stability of curcumin in liposomes were markedly improved with increasing the amount of Sito. First-order kinetics fitted best the curcumin release dynamics of Sito containing liposomes, clearly showing that sustained release improved with increasing amounts of Sito in liposomes. Simulated digestion studies suggested that Sito concentration of about 20–33 mol% improved the bioavailability of curcumin in liposomes. These study shows that Sito is an applicable and potential route in forming healthier cholesterol-free curcumin-loaded liposomes for functional supplements. [ABSTRACT FROM AUTHOR]

The effects of three kinds of sterols (cholesterol, β-sitosterol and ergosterol) on the stability, microstructure and membrane properties of soybean and egg yolk lecithin liposomes were investigated by light scattering, transmission electron microscope (TEM), atomic force microscope (AFM), fluorescence and Fourier transform infrared spectroscopy (FTIR). The vesicle size of cholesterol or β-sitosterol incorporated liposomes was higher than that of the control and ergosterol incorporated ones, while the zeta-potential was similar when the same lecithin was used. Due to the excellent emulsifying capacity, Tween-80 was introduced into the system and which could obviously maintain the liposomal vesicle size in fetal bovine serum. According to TEM and AFM, the phenomena of membrane fusion and deformation were observed respectively in ergosterol-incorporated liposomes. Results of fluorescence probe spectra revealed the most compact membrane structure was found in cholesterol-incorporated liposomes, which was in accordance with the strongest intermolecular interaction in bilayers obtained by FTIR results. Conversely, the membrane of ergosterol-incorporated liposomes was the most fragile and fluid, which was also identified with the lowest physical stability obtained by Turbiscan. These results systematically illustrated the relationship between the structure of sterols and the liposomal membrane stability, and provided some meaningful information on the choice of sterols and lecithin in preparation of liposomes for different purposes. [ABSTRACT FROM AUTHOR]

High pressure processing (HPP) is a non-thermal technology and has been widely used in the food industry. β‑lactoglobulin (β-Lg) is a globular protein and susceptible to pressure. This study investigated the properties of β-Lg gels induced directly by HPP (0.1–600 MPa for 30 min, 25 °C) with different protein concentrations at different pH. Results showed that the lowest protein concentration required to form β-Lg gels was 20% (w/v) at 400 MPa for 30 min at pH 3.0, 5.0 and 7.0, while 14% (w/v) protein was required to form gels at 600 MPa. The gel strength and textural properties increased with the increase of protein concentration and pressure, the gel formed at pH 5.0 had the highest strength. Raman spectra suggested that the content of α-helix decreased and random coil increased of β-Lg in gels with the increase of pressure. β-Lg gels formed more regular and stable network under 600 MPa than that under 400 MPa. Industrial relevance In recent years, high pressure processing (HPP) has been used in the food industry as an innovative technology to improve gel properties of various kinds of proteins, including β‑lactoglobulin, casein, soy protein isolate, surimi, mytolin and so on. It was found that HPP could change the structure of protein, which could cause protein denaturation and aggregation and three-dimensional network structures were formed through disulfide bonds, electrostatic interactions, hydrophobic interaction, hydrogen bonds and others. β‑lactoglobulin is the main component of whey protein, which has been widely used in the food industry as gelling agents. β‑lactoglobulin gels could be used as a wall material and applied to the delivery system of functional components such as riboflavin. The objective of the current study was to investigate the properties of β-Lg gels formed through HPP directly, focusing on the effects of pressure, protein concentration and pH on the rheological properties, texture profile, protein secondary structure and microstructure of β-Lg gels. [ABSTRACT FROM AUTHOR]

The effects of different heat-treated temperatures (75, 85 and 95 °C) and times (15, 30 and 45 min) on physical, structural, thermal and morphological characteristics of zein in ethanol-water solution were investigated. The result of particle size distribution suggested that the volume percentage of small zein colloidal nanoparticles (d < 200 nm) was increased from 87.9% to 98.2% after heat treatment at 75 °C for 15 min. Both of the fluorescence intensity and ultraviolet absorption of zein approached to the maximum value when zein solution was heated at 95 °C for 30 min. Differential scanning calorimetry thermograms implied that heat treatment enhanced the thermal stability of zein with the rise of denaturation temperature. The secondary structure changes of zein induced by heat treatment might be explained by a potential mechanism of three-step process, including partial protein folding, a larger extent unfolding and the formation of partial protein aggregates. In addition, heat treatment significantly modified the morphology of zein from the typical sphericity to distinct oval at 75 and 85 °C, as well as obvious dumbbell-like shape at 95 °C for 30 min. [ABSTRACT FROM AUTHOR]

The fourth-generation synchrotron radiation light source under construction has a higher requirement for alignment measurement than former-generation light sources, including the accuracies and efficiencies. In this paper, a robust smoothing analysis strategy that aims to reduce relative position errors is introduced to smooth the magnetic centers' orbit. First, we pre-process the original data based on gross error detection. Then, we do a smooth analysis of the data of the magnetic centers' orbit and iteration by using the curve fitting of the Parzen-window function. Finally, the physical accelerator calculation is utilized to terminate the iteration. Simulation results based on the Hefei Advanced Light Facility show that the comparison between the physical calculation results before and after using this strategy verifies that it can dramatically improve beam quality, which has a slight improvement concerning existing methods. Besides, this strategy requires lower quantities of magnets that need to be adjusted, less than that of other methods. This research can provide a robust technical guarantee for the construction of the fourth-generation light source. [ABSTRACT FROM AUTHOR]

Curcumin is a natural food coloring agent with many pharmacological effects such as anti-oxidation and anti-cancer. In this study, curcumin was dissolved in different oil phases (medium chain triglyceride, canola oil and linseed oil) by different treatments (heat, ultrasonic and microwave). Curcumin nanoemulsions stabilized by different emulsifiers (Tween-80, lecithin, whey protein isolation and acacia) with different concentrations were prepared using high pressure homogenization to evaluate physicochemical properties including curcumin content, particle size, potential, physical stability and storage stability (variation of curcumin content and particle size under different temperatures in 60 days). The increase in oil phase concentration caused increase in curcumin content, particle size and viscosity of the emulsions but decrease in stability. Meanwhile, temperature significantly affected the stability of nanoemulsion stabilized by lecithin instead of Tween-80. Curcumin nanoemulsion could achieve the maximum curcumin content when choosing medium chain triglyceride as its oil phase. These results may broaden the application of curcumin in food industry for improving its solubility and bioavailability. [ABSTRACT FROM AUTHOR]