Hydrophobic Components Research Articles

Underwater Adhesives Produced by Chemically Induced Protein Aggregation

AbstractBarnacles convert hydrophilic proteins into an insoluble, yet aqueous, material that functions as a permanent underwater adhesive. Here, it is demonstrated that a common hydrophilic protein, bovine serum albumin, can be chemically triggered underwater to aggregate into a similar aqueous adhesive that mimics the formation of the natural adhesive. The combined action of multiple chemical denaturants initiates rapid gelation followed by further curing over time in artificial seawater. The adhesive strengths of this waterborne adhesive measured by lap shear are comparable to many bioinspired adhesives that use organic solvents and a high fraction of hydrophobic components. This approach establishes a bioinspired adhesive that can be deployed at practical scales in marine environments, produced sustainably, and sourced from low‐cost materials.

Characterization of Microplastic Leachate from Different Polymers and Its Effect on Seed Germination of Lettuce

Accumulation of microplastics in soil could interfere with the germination and growth of plants. However, the chemical risks raised by leachate of microplastics remain unknown. Here, we prepared microplastic leachate at different extraction temperatures (25 and 50℃) using microplastic fibers derived from polyamide (PA) and polyethylene (PE) and conducted the seed germination test of microplastic leachates to investigate the toxic effects of microplastic leachates on lettuce (Lactuca sativa L.). Furthermore, characteristics of the microplastic leachate, such as DOC and DON concentrations and parameters of UV-vis, were measured. The results revealed that the concentration of DOC and DON in the leachate of PA was significantly higher than that of PE. DOC and DON concentration in the leachate of PA increased with extraction temperature. Additionally, the aromaticity, hydrophobic component content, and molecular weight of leachates were significantly affected by the polymers of microplastic, whereas the extraction temperature had no effect. Compared to those in CK, the microplastic leachates reduced the indicators such as germination vigor, germination index, and vigor index of lettuce seeds; however, it had no impact on agronomic traits, such as plant height, root length, fresh weight, and dry weight. Meanwhile, some seeds had abnormal developments of radicles and cotyledons under the microplastic leachate treatments. This demonstrates that the substances leached from microplastics could interfere with the germination process of lettuce seeds. Therefore, the chemical risks exerted by the microplastics to the soil and plant system require further attention.

Study on atomization mechanisms and spray fragmentation characteristics of water and emulsion butachlor.

Agricultural chemicals are commonly used to control pests and weeds, but cause pesticide waste problems. Oil-based emulsions are often used as pesticide formulations to improve pesticide utilization. In this study, the spray visualization experiment of the water and oil-based emulsion butachlor is carried out using an ST flat fan nozzle at 0.1-0.5 MPa pressure. The dimensionless method is used to analyze the difference in liquid sheet fragmentation morphology and disintegration process and the influence of different fragmentation methods on droplet size. It is found that the hydrophobic components in pesticide have a significant effect on the morphology and process of atomization fragmentation. When spray liquid is water, the liquid sheet breaks up into liquid ligaments due to the Rayleigh instability, then the ligaments break up into droplets. The side view of a liquid sheet is a large-amplitude wave disturbance. When the spray liquid is the emulsion butachlor, holes are generated on the liquid sheet, then the holes break up into droplets. The fragmentation method of emulsion spray is the perforation mechanism. Compared with water spray, the presence of the pesticide butachlor increases the droplet size and spray angle and improves the uniformity of droplet size distribution but reduces the breakup length. The spray angle shows a power law dependence of the Weber number with a power of 0.17 for all conditions tested here. At 0.3 MPa, DV50 increases 25%, and span decreases from 1.187 to 1.172. This study could provide reference for the addition of agricultural additives, the improvement of spray operation efficiency, and the establishment of spray fragmentation mechanism.

Effect of Grasslands Fertilisation on Soil Organic Matter Quality and Nutrients Status

Abstract Soil organic matter (SOM) represents one of the largest and most important reservoirs of organic carbon in terrestrial eco-systems. The quality of SOM (e.g., content of soil organic carbon, humic substances, humic acids, fulvic acids, and HA/FA ratio) is a key factor in determining soil fertility and productivity. The loss of SOM is currently considered a detrimental form of soil degradation. The study aims to evaluate the effect of mineral fertilising (NPK), farmyard manure, cattle slurry, and digestate applications in intensively used permanent grassland. The long-term field experiments were carried out at the locality Jevíčko, region of Boskovice Furrow Malá Haná (the Czech Republic). The effect of amending soil with different organic and mineral fertilisers was studied. Qualitative parameters of SOM, soil reaction, and the content of available nutrients (N, P, K, Ca, Mg) were followed. Results showed that the control (no organic input) and the NPK variants had the lowest SOM quality. Higher SOM quality was after the farmyard manure, Slurry, and Digetsate applications. The highest acidity (indicated by the lowest values of pH/KCl) was determined in the control, NPK, Slurry, and D variants. The most favourable soil reaction and available nutrient content were after the farmyard manure application. Humic substances spectral absorption in the UV-VIS and infrared spectral ranges showed that the highest absorbance and amount of aliphatic hydrophobic components were observed after the application of farmyard manure. The multi-criteria statistical evaluation, including principal component analysis and factor analysis, confirmed that amending soil with farmyard manure and slurry resulted in an increase in humic substances content and improved SOM quality.

Nanostructured systems based on polymethylsiloxane and nanosilicas with hydrophobic and hydrophilic functionalities

Nanostructured adsorbents composed of nanoparticles with hydrophobic and hydrophilic surface functionalities are of interest for practical applications due to the dual nature of their surfaces. To prepare nanostructured hydrogels including a hydrophobic component, its hydrophobicity should be low, e.g., due to the shortest hydrophobic functionalities (–CH3). Therefore, hydrophobic nanosilica (AM1) and polymethylsiloxane (PMS) both with methylsilyl functionalities and residual silanols were selected as components of composites with hydrophilic nanosilica A–300. These hydrophobics were well wetted–stirred with A–300 to control the blend hydrophilicity. To analyze interfacial phenomena in PMS(AM1)/A–300, the temperature behavior of bound water alone or with different co-sorbates and solutes was studied in various dispersion media using low-temperature 1H NMR spectroscopy of static samples. The adsorbents were studied using microscopy, spectroscopy, thermogravimetry, adsorption, and quantum chemistry methods. Obtained results allow us to elucidate several general regularities, caused by the nano-morphology, texture, and structure of components and blends located in different dispersion media, related to the interfacial and temperature behaviors of bound compounds depending on pretreatments changing the organization of ‘soft’ nanostructured systems. This study allows one a deeper insight into the interfacial phenomena in nanostructured hydrophobic/hydrophilic PMS(AM1)/A–300 blends, which could be of interest from a practical point of view for applications as, e.g., drug delivery systems characterized by prolonged release varied for hydrophilic and hydrophobic drugs due to changes in the blend components and their pretreatments.

Quantification of carbon black tattoo ink hydrophobicity pre- and post-sonication

Abstract Despite growing academic interest for dermal inking in contemporary society, the reason why skin tattoos remain visible for life has predominantly been studied from a biological perspective. In preliminary physics studies of ink it has been presumed that the hydrophobicity of its main constituent prevents further dilution of pigment dispersion and therefore may be a contributing factor to aforementioned lifelongevity. According to these early studies, ultrasound might change the hydrophobicity of microparticles. The purpose of this study was to confirm or refute the presence of hydrophobic components in carbon black tattoo ink and to relate sonication to such presence. Cuvettes with n-octanol, distilled water, and a droplet of unsonicated or sonicated carbon black ink were shaken, allowed to settle and subsequently photographed. The sonicated ink had been subjected to ultrasound during 5 min at a centre frequency of 1 MHz, a pulse-repetition frequency of 1 kHz, and a 10% duty cycle. The greyscale values in both parts of the cuvettes were averaged. The resulting ratio of light intensities was an indicator for the ink hydrophobicity. The intensity partition coefficient of carbon black ink was measured to be greater than 103 before sonication and less than 103 after sonication. Carbon black tattoo ink was found to be very hydrophobic. However, sonication was found to make the dispersion less hydrophobic. Influencing the hydrophobicity of tattoo ink might change the permanence of a skin tattoo.

Alginate/guacamole edible films as moisture barrier layers in multicomponent foods

AbstractIn multicomponent foods having both moist and dry components (e.g., pizzas and tacos), moisture migration between components causes undesirable texture changes (e.g., loss of crispiness of the dry component). In this study, different proportions of alginate (film matrix), guacamole (hydrophobic component with sensory appeal), and glycerol (plasticizer) were combined to form edible films to be used as a moisture barrier between moist and dry components of multicomponent foods. Alginate was the component that most contributed to increase the film strength and to reduce its water vapor permeability (WVP). Guacamole, due to the presence of avocado lipids, enhanced the film hydrophobicity, although not having decreased the WVP (as expected), since it promoted discontinuities in the alginate structure. The film with the lowest WVP (containing an alginate/guacamole/glycerol dry mass ratio of 25/60/15) was inserted between nachos and tomato sauce, being able to reduce the crispiness loss of nachos during a 50‐min storage.

THEORETICAL BASICS OF MONITORING THE CONDITION OF THE ELECTRODES OF CHEMICAL CURRENT SOURCES BY THE METHOD OF ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY

On the basis of the conducted critical review of modern physical models of the porous electrode, it сan be stated that under the conditions of non-uniform mass transfer taking into account the depth of the electrode, it is possible not only to develop new porous electrodes for a certain application, but also to control the state of electrochemical systems as a whole using the non-destructive method of electrochemical impedance spectroscopy. The presence of a macroscopic model of porous electrode allows one to use the integration of parameters over the surface of the electrode and obtain the average values of current, resistance and capacity within the electrode using the method of averaging in the volume ele­ment within the electrode, where porosity is the volume fraction of the void within the element, which is filled with electrolyte solution. This is the theoretical basis for using electrochemical impedance spectroscopy to assess the state of electrodes in electrochemical current sources. To take into account the influence of the aqueous electrolyte, it is possible to use a model taking into account the area of the effective wetted surface, which makes it possib­le to relate the wetting of the electrode pores with the electrolyte solution to the change in electrical conductivity and polarization of the electrode surface. In this case, when usingelectrochemical impedance spectroscopy, it is possible to obtain information about the following changes in primary current sources: 1– the effect of temperature, which leads to a decrease in the areas of the electrode wetted by the electrolyte, which affect the value of the capacity of the DEL, 2 – chemical processes that lead to the destruction of hydrophilic pores and pores with hydrophilic-hydrophobic walls, an increase in the hydrophobic component on the surface of the electrode, 3 – mechanical destruction of the electrodes. The use of models that take into account the geometry of pores makes it possible to obtain correct data for the analysis of the porous surface in the presence of an electrolyte and in cases of gas phase adsorption in presence of closed pores, as well as to use the value of the capacity on the surface of electrodes to assess the state of their performance.

The Role of Virgin Coconut Oil in Corn Starch/NCC-Based Nanocomposite Film Matrix: Physical, Mechanical, and Water Vapor Transmission Characteristics.

Corn starch-based nanocomposite films usually have low moisture barrier properties. Adding virgin coconut oil (VCO) as a hydrophobic component can improve the nanocomposite film's characteristics, especially the film's permeability and elongation properties. This study aimed to determine the role of VCO with various concentrations (0, 3, 5 wt%) on the physical, mechanical, and water vapor transmission characteristics of corn starch/NCC-based nanocomposite films. Adding 3% VCO to the film showed the lowest WVTR value by 4.721 g/m2.h. At the same time, the value of tensile strength was 4.243 MPa, elongation 69.28%, modulus of elasticity 0.062 MPa, thickness 0.219 mm, lightness 98.77, and water solubility 40.51%. However, adding 5 wt% VCO to the film increased the film's elongation properties by 83.87%. The SEM test showed that adding VCO formed a finer structure with pores in several areas. The FTIR films showed that adding VCO caused a slightly higher absorption peak shift at the O-H groups and new absorption peaks at wave numbers 1741 cm-1 and 1742 cm-1. The results of this study may provide opportunities for the development of nanocomposite films as biodegradable packaging in the future.

Nanoemulsions as medicinal components in insoluble medicines

Background: Medicine’s success relies on solubility, which is the process of dissolving a solid substance in a fluid phase to create a uniform molecular dispersion. However, hydrophobic active medicinal components exhibit poor solubility in water, limiting their effectiveness and incorporation into medications. Aim: This review explores the potential of nanoemulsions as a solution for delivering hydrophobic medicinal components with low solubility. The study investigates the benefits of nanoemulsions, including enhanced absorption, effective targeting, controlled release, and protection of encapsulated bioactive ingredients. Materials and methods: Nanoemulsions are formulated by combining two immiscible liquids with emulsifying agents within a thermodynamically stable colloidal dispersion system. The review categorizes various preparation techniques into high-energy and low-energy spontaneous emulsification methods. The choice of preparation procedures and materials used significantly affects the stability of nanoemulsions over time. Evaluation of nanoemulsions includes studying medication release in vitro, in vitro permeation, stability and thermodynamic stability, shelf life, viscosity, interfacial tension, pH, and osmolarity. Results: Nanoemulsions, such as Celecoxib (Phase Inversion), acetylsalicylic acid (Ultrasonication), and Flurbiprofen (Homogenization and Ultrasonication), offer distinct advantages for medications with low solubility compared to conventional emulsions. These nanoemulsions comprise small droplets with a larger surface area, promoting enhanced absorption. They demonstrate effective targeting, controlled release, and protection of encapsulated bioactive ingredients. Moreover, the diminutive droplet sizes of nanoemulsions contribute to their reduced susceptibility to issues like flocculation, coalescence, sedimentation, or creaming. Conclusion: Nanoemulsions hold great promise in overcoming the solubility limitations of hydrophobic medicinal components. They provide enhanced absorption, effective targeting, controlled release, and protection of bioactive ingredients. The choice of preparation techniques and materials plays a crucial role in ensuring the stability of nanoemulsions over time. Further studies are warranted to optimize their use and explore their potential applications in drug delivery systems.

The Influence of Functional Materials on the Size of the Lipid Vesicles in Beverages

By investigating the hydrophobic properties and functional components including ethyl caproate (EC), caproic acid (CA), isoamyl acetate (IA), isoamyl alcohol (IAA), isovaleraldehyde (IVA), and procyanidin B2 (PB2) in beverages, one can incorporate them with 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) lipids to create cell-sized lipid vesicles. The aim of this study was to explore the correlation between the concentration of flavors or functional compounds and the size of the lipid vesicles. It was observed that EC, CA, IA, and IAA decreased the size of lipid vesicles. In contrast, IVA and PB2 increased their size. To comprehend this correlation, both the chemical structure of these compounds in relation to DOPC membranes and the fluidity of the membranes were considered. The size of the lipid vesicles was influenced by the molecular interactions between the compounds and DOPC. Those were caused by, in particular, the balance between hydrophobicity and hydrophilicity. Compounds with higher hydrophobicity tended to decrease the size of the lipid vesicles, whereas compounds with greater hydrophilicity had the opposite effect, leading to an increase in size. These findings suggest that the size of lipid vesicles can serve as a potential indicator for rapidly evaluating the concentration of these components in beverages.

Emulgel: An Effective Drug Delivery System

When emulgel comes to administering hydrophobic medications, many of the benefits of gels are also severe disadvantages. An emulsion-based strategy is adapted to bypass barriers, giving even a hydrophobic medicinal component to take advantage of the special features of gels. Emulgel is a dosage form that combines gels and emulsions. The utilization of novel polymers has sparked a lot of curiosity in recent years. The direct convenience of the skin as a target organ for diagnostic and therapeutic objectives distinguishes dermatological pharmacology. Both hydrophilic and hydrophobic chemicals are blocked by this barrier is created by combining hydrophilic horn cells with a hydrophobic intercellular medium. Within the primary group of semi-solid preparations, the use of opaque gels in cosmetics and pharmaceutical preparations has grown. By lowering surface and interfacial tensions while raising aqueous phase viscosity, these chemicals allow the formation of stable emulsions and creams. An emulgel is created by adding a gelling ingredient to a conventional emulsion's aqueous phase. In various ways, these emulsifiers exceed both novel vesicular systems and traditional systems. Using various permeation enhancers, emulsifiers could be used as better topical medication delivery systems than they are today. The use of emulsifiers can be expanded to include analgesics and antifungals. Analgesics and antifungals can both benefit from emulsifiers. We discuss the types, advantages, marked emulgel, formulation of emulgel, emulgel preparation, and characterization.

Role of energy transfer in a nanoinitiator complex for upconversion-driven polymerization

Upconversion nanoparticle (UCNP)-driven polymerization attracts great attention due to the ability of near-infrared light to penetrate deeper into biological media and synthetic materials than ultraviolet or visible light. Despite significant progress, the limitation of near-infrared light-triggered polymerization is associated with a key element of the photocurable composition, a UCNP/photoinitiator complex or a nanoinitiator. To determine the impact of resonance energy transfer from UCNPs to photoinitiator (PI) and its effect on polymerization, we developed two different photocurable compositions consisting of the polyethylene glycol diacrylate (PEG-DA), ultraviolet- and blue-emitting NaYF4: Yb3+, Tm3+ UCNPs with hydrophobic surface combined with water-soluble or insoluble PI. We found that transfer energy in these nanoinitiators proceeds differently: in UCNP/water-soluble PI (lithium phenyl-2,4,6-trimethylbenzoylphosphinate or LAP), it occurs through the photon-mediated transfer while in UCNP/water-insoluble PI (2-benzyl-2-(dimethylamino)-4′-morpholinobutyrophenone or Irgacure 369), it takes place via the non-radiative resonant energy transfer. The impact of these processes in homolytic decomposition of initiator is extremely important in terms of the precisely controlled fabrication of polymer structures. PEG-DA facilitates the affinity between hydrophilic and hydrophobic components of the photocurable composition, which provides UCNP-driven cross-linking of biopolymers such as methacrylated hyaluronic acid and gelatin. 3D structures were prototyped to demonstrate the one-step rapid procedure of nanoinitiator preparation and emphasize the control of the energy transfer in UCNP/PI complexes for further development of UCNP-driven polymerization.

Role of visible light photocatalysis in alleviation and mechanism transformation of ultrafiltration membrane fouling caused by natural organic matter

In this study, a novel composite based on bismuth oxide, reduced graphene oxide and titanium dioxide (labeled as BRGT) was utilized for visible light photocatalysis to mitigate ultrafiltration membrane fouling caused by natural organic matter (NOM). The results show that the coexistence of NOM and the BRGT composite (without photocatalysis) did not aggravate membrane fouling, and the membrane preferentially retained a high molecular weight, hydrophobic component of NOM that formed a dense cake layer with BRGT composite. As the photocatalysis time increased, the extent of membrane fouling was alleviated. The maximum specific flux recovered from 0.21 to 0.73 at 60 min, and the hydraulic reversible and irreversible resistances ere 1.15 × 1010 and 4.23 × 1010 m−1, respectively. The reduction of NOM in the feed water, especially the removal of UV254, played a significant role in the alleviation of membrane fouling. Additionally, the changes in the properties of NOM, including the reduction of fluorescent humic and protein/polyphenol components corresponding to reversible and irreversible fouling, respectively, the photo-degradation of high molecular weight NOM into low molecular weight NOM (such as low molecular weight-acids), and the conversion of hydrophobic fractions into hydrophilic fractions, contributed to the mitigation of membrane fouling. We also found a strong negative correlation between the roughness of the cake layer and irreversible fouling. Overall, the changes in the properties of NOM in feed water can hinder or even inhibit the formation of the cake layer, and the use of visible light photocatalysis of the BRGT composite has great potential to alleviate ultrafiltration membrane fouling caused by natural organic matter.

Crystallization inhibitory effects of konjac glucomannan, sodium alginate and xanthan gum on curcumin in supersaturated solution

Supersaturating drug delivery system (SDDS) is a promising approach to enhance the solubility of hydrophobic functional components. However, SDDS is thermodynamically unstable and crystallization tends to occur. In this work, curcumin was used as a model compound, and the crystallization inhibitory effect of konjac glucomannan (KGM), sodium alginate (SA) and xanthan gum (XTG) on curcumin in supersaturated solution was investigated. Amorphous solubility of curcumin was determined using ultraviolet extinction, fluorescence spectroscopy and dynamic light scattering methods. Nucleation induction time (NIT) and crystal growth rate of curcumin were evaluated using ultraviolet probe in the absence and presence of various natural polysaccharides (NPs). Results showed that amorphous solubility of curcumin was approximately 30 μg/mL in pH 6.8 phosphate buffer. NPs used in this work restrained nucleation or crystal growth of curcumin effectively. The NITs of curcumin in the absence of NPs and in the presence of XTG, KGM and SA (1 μg/mL) were 3.7, 60.7, 20.0 and 8.0 min, respectively. The crystal growth rate of curcumin in the absence of NPs and in the presence of XTG, SA and KGM (1 μg/mL) were 0.0103, 0.00752, 0.00286 and 0.000306 min−1, respectively. The nucleation inhibitory effect of NPs on curcumin was ranked as XTG > KGM > SA. The order of crystal growth inhibition capacity of NPs was KGM > SA > XTG. In conclusion, NPs could be incorporated into SDDS to maintain supersaturation of hydrophobic components for enhanced bioavailability.

Milk Exosomes: Next-Generation Agents for Delivery of Anticancer Drugs and Therapeutic Nucleic Acids.

Exosomes are nanovesicles 40-120 nm in diameter secreted by almost all cell types and providing humoral intercellular interactions. Given the natural origin and high biocompatibility, the potential for loading various anticancer molecules and therapeutic nucleic acids inside, and the surface modification possibility for targeted delivery, exosomes are considered to be a promising means of delivery to cell cultures and experimental animal organisms. Milk is a unique natural source of exosomes available in semi-preparative and preparative quantities. Milk exosomes are highly resistant to the harsh conditions of the gastrointestinal tract. In vitro studies have demonstrated that milk exosomes have an affinity to epithelial cells, are digested by cells by endocytosis mechanism, and can be used for oral delivery. With milk exosome membranes containing hydrophilic and hydrophobic components, exosomes can be loaded with hydrophilic and lipophilic drugs. This review covers a number of scalable protocols for isolating and purifying exosomes from human, cow, and horse milk. Additionally, it considers passive and active methods for drug loading into exosomes, as well as methods for modifying and functionalizing the surface of milk exosomes with specific molecules for more efficient and specific delivery to target cells. In addition, the review considers various approaches to visualize exosomes and determine cellular localization and bio-distribution of loaded drug molecules in tissues. In conclusion, we outline new challenges for studying milk exosomes, a new generation of targeted delivery agents.

The Nanostructured Self-Assembly and Thermoresponsiveness in Water of Amphiphilic Copolymers Carrying Oligoethylene Glycol and Polysiloxane Side Chains.

Amphiphilic copolymer self-assembly is a straightforward approach to obtain responsive micelles, nanoparticles, and vesicles that are particularly attractive for biomedicine, i.e., for the delivery of functional molecules. Here, amphiphilic copolymers of hydrophobic polysiloxane methacrylate and hydrophilic oligo (ethylene glycol) methyl ether methacrylate with different lengths of oxyethylenic side chains were synthesized via controlled RAFT radical polymerization and characterized both thermally and in solution. In particular, the thermoresponsive and self-assembling behavior of the water-soluble copolymers in water was investigated via complementary techniques such as light transmittance, dynamic light scattering (DLS), and small-angle X-ray scattering (SAXS) measurements. All the copolymers synthesized were thermoresponsive, displaying a cloud point temperature (Tcp) strongly dependent on macromolecular parameters such as the length of the oligo(ethylene glycol) side chains and the content of the SiMA counits, as well as the concentration of the copolymer in water, which is consistent with a lower critical solution temperature (LCST)-type behavior. SAXS analysis revealed that the copolymers formed nanostructures in water below Tcp, whose dimension and shape depended on the content of the hydrophobic components in the copolymer. The hydrodynamic diameter (Dh) determined by DLS increased with the amount of SiMA and the associated morphology at higher SiMA contents was found to be pearl-necklace-micelle-like, composed of connected hydrophobic cores. These novel amphiphilic copolymers were able to modulate thermoresponsiveness in water in a wide range of temperatures, including the physiological temperature, as well as the dimension and shape of their nanostructured assemblies, simply by varying their chemical composition and the length of the hydrophilic side chains.

Assembly of perilla seed protein isolate-pectin nanocomplex to deliver curcumin: Properties, characterization, molecular interactions and antioxidant activity

In the present study, nanocomplexes composed of perilla seed protein isolate (PSPI) and pectin (PEC) were assembled for the delivery of curcumin (Cur) based on the pH-driven self-assembly method. The encapsulation efficiency of Cur was 87.77%, and the PSPI-Cur-PEC exhibited controlled release of Cur during the in vitro digestion. Moreover, the PSPI-Cur-PEC possessed efficient antioxidant activity and provided greater defense for Cur against thermal treatment and ultraviolet irradiation. Fourier transform infrared spectroscopy, fluorescence spectroscopy and X-ray diffraction results indicated that entrapped Cur was existed in the form of amorphous state in PSPI-PEC, and the process was driven by hydrophobic effects, hydrogen bonding and electrostatic interactions. Scanning electron microscopy images revealed substantial morphological changes of the nanocomplexes throughout the process, while transmission electron microscopy images observed the core-shell structure of PSPI-Cur-PEC nanocomplexes. Furthermore, PSPI-PEC exhibited excellent biocompatibility by the in vitro cytotoxicity assay on Caco-2 cells, and the intermolecular interactions and possible formation mechanism of PSPI-Cur-PEC were further determined by molecular docking. This work elucidated that PSPI-PEC nanocomplexes assembled by a green and energy-efficient pH-driven method was feasible to protect sensitive hydrophobic bioactive components and provided a possible utilization of perilla seed protein in delivery system for nutraceuticals.

Hemp seed oil nanoemulsion with Sapindus saponins as a potential carrier for iron supplement and vitamin D

Abstract Vitamin D3 and iron are important components of a balanced diet. Supplementing meals with these is essential to support the recovery of humankind’s malnutrition. It is necessary to develop effective delivery systems to ensure the high bioavailability of these hydrophobic components. For this purpose, emulsions were prepared based on hemp seed oil and with soap nut extract (Sapindus mukorossi fruits) as a natural emulsifier. To characterize the differences in the properties of the emulsions depending on the content of the oil phase and the emulsifier, measurements were performed to determine the following parameters: the color characteristics, transparency of the samples, infrared spectrum, particle size distribution, polydispersity of the system, and the rheological properties of the emulsions. The results showed that the highest stability was observed in systems with a relatively low oil concentration, i.e., 1%. These samples also had an average particle size not exceeding 200 nm. In turn, the low oil content significantly reduced the dynamic viscosity of the emulsions. At the same time, microscopic observations indicated that the presence of an oil phase was advantageous, not only because of the possibility of providing vitamin D but also because of the high hydrophobicity of the iron particles. Therefore, the realized research made it possible to identify the optimal emulsion composition. The created system can find applications in delivering dietary supplements such as vitamin D3 and iron by providing high dispersion of components and high stability.

Lipid A structural diversity among members of the genus Leptospira.

Lipid A is the hydrophobic component of bacterial lipopolysaccharide and an activator of the host immune system. Bacteria modify their lipid A structure to adapt to the surrounding environment and, in some cases, to evade recognition by host immune cells. In this study, lipid A structural diversity within the Leptospira genus was explored. The individual Leptospira species have dramatically different pathogenic potential that ranges from non-infectious to life-threatening disease (leptospirosis). Ten distinct lipid A profiles, denoted L1-L10, were discovered across 31 Leptospira reference species, laying a foundation for lipid A-based molecular typing. Tandem MS analysis revealed structural features of Leptospira membrane lipids that might alter recognition of its lipid A by the host innate immune receptors. Results of this study will aid development of strategies to improve diagnosis and surveillance of leptospirosis, as well as guide functional studies on Leptospira lipid A activity.