Hydrophobic Nutraceuticals Research Articles

Improved water solubility, chemical stability, antioxidant and anticancer activity of resveratrol via nanoencapsulation with pea protein nanofibrils

Fabricated pea protein isolate (PPI) nanofibrils were used as nanocarriers to encapsulate, stabilize and deliver resveratrol (RES). PPI nanofibrils possessed a dramatically higher surface hydrophobicity than PPI (native), and PPI nanofibrils exhibited nanoscale widths of 10 nm and average lengths of 1.0 μm. Fluorescence analyses demonstrated PPI nanofibrils had high binding constant with RES. Compared with RES (free), the aqueous solubility of RES was improved by approximately 1000-fold with PPI nanofibrils complex. DPPH and ABTS radical scavenging activity assays showed that the antioxidant capacity of RES was pronouncedly enhanced through the nanocomplexation with PPI nanofibrils. RES-PPI nanofibrils complexes exhibited higher antiproliferative activities than RES (free), with the cell viabilities of 52.6% and 38.5% for RES (free) and RES-PPI nanofibrils complex at 20 μg/mL. This study demonstrates that PPI nanofibrils can be utilized as novel nanocarriers for improvements of the water solubility, chemical stability and in vitro biological activities of hydrophobic nutraceuticals.

Enhancement of the physicochemical and in vitro release properties of lutein by gelatin/octenyl succinic anhydride (OSA)‐modified starch composite as vehicles

SummaryIn this study, the lutein was microencapsulated by complex coacervation with gelatin and OSA starch as vehicles, and the physicochemical and in vitro release properties of the microcapsules were evaluated followed by the spray drying or freeze‐drying method. Preliminary assays of coacervation indicated that a higher encapsulation efficiency was obtained at the gelatin/OSA starch volume ratio of 5:4 and the core/wall material volume ratio of 1:8 (v/v) followed by the spray‐drying method. The lutein‐gelatin‐OSA microcapsules had a higher solubility, antioxidant activity, thermostability, relative humidity stability and sustained in vitro release compared to the free lutein. Fourier transform infrared data indicated that the encapsulated lutein interacted with gelatin and OSA starch was mainly through hydrogen bonding, hydrophobic and electrostatic interactions. The freeze‐dried microcapsule was observed with a more regular shape, smaller particle size in morphology and confirmed with better thermal stability from the differential scanning calorimetry results while the spray‐dried microcapsules obtained a higher cumulative release rate of lutein and higher antioxidant activity. The results of this study are expected to contribute to the design and commercial application of gelatin‐OSA starch complex‐based delivery systems for hydrophobic nutraceuticals with desired physicochemical properties and digestive performance.

Sugar beet pectin as a natural carrier for curcumin, a water-insoluble bioactive for food and beverage enrichment: Formation and characterization

Food and beverages enrichment with water-insoluble health-promoting nutraceuticals is important, but technologically challenging. Sugar beet pectin (SBP) is a natural dietary fiber with high emulsifying capacity. However, its potential as a natural encapsulator of hydrophobic nutraceuticals for beverage enrichment, has hardly been explored. Curcumin is a potent antioxidant with numerous attributed health benefits, but very low aqueous-solubility. We herein explored SBP as a carrier for solubilization and protection of curcumin (CUR). Using spectrofluorimetry, the CUR-SBP binding constant determined was (6.74 ± 0.5) ∙ 105M−1. As CUR:SBP molar ratio increased from 14:1 to 140:1, CUR encapsulation capacity increased from 14.5 ± 0.8 to 127.4 ± 0.4 mg CUR/gSBP, and encapsulation efficiency moderately decreased from ~100% to 86 ± 7%. The encapsulation in SBP dramatically decreased CUR particle size, from >17 μm to <0.5 μm, in average, and conferred substantial protection to CUR during simulated shelf-life, decreasing the decay rate constant ~7 fold. Therefore, SBP is a potent natural encapsulator for hydrophobic nutraceuticals for food and even clear beverage enrichment.

Synthesis and characterization of lotus seed protein-based curcumin microcapsules with enhanced solubility, stability, and sustained release.

Lotus seed protein (LSP) was extracted from lotus seed and used to encapsulate curcumin with or without complexing with pectin. The physicochemical properties of LSP-based microcapsules, including solubility, stability, and in vitro sustained release, were determined. The mechanism of interaction between curcumin, LSP, and pectin was revealed. The encapsulation efficiency of curcumin was found to depend on LSP concentration and was highest (86.32%, w/w) at 50 mg mL-1 . The curcumin in curcumin-LSP and curcumin-LSP-pectin powder particles achieved a solubility of 75.15% and 81.39%, respectively, which was a remarkable enhancement. The microencapsulation with LSP and LSP-pectin matrix showed a significant improvement in the antioxidant activity, photostability, thermostability, and storage stability of free curcumin. The microencapsulated curcumin showed sustained control release at the gastric stage and burst-type release in the subsequent intestinal stage, presenting cumulative release rates of 64.3% and 72.4% from curcumin-LSP and curcumin-LSP-pectin particles after gastrointestinal digestion. The LSP-pectin complex produced microcapsules with higher solubility, smaller particle size, enhanced physicochemical stability, and increased bioaccessibility. Fourier transform infrared, circular dichroism spectra, and differential scanning calorimetry data indicated that the encapsulated curcumin interacted with LSP and pectin mainly through hydrogen bonding, hydrophobic, and electrostatic interactions. This work shows that LSP can be an alternative encapsulant for the delivery of hydrophobic nutraceuticals with enhanced solubility, stability, and sustained release. The results may contribute to the design of novel food-grade delivery systems based on LSP vehicles, thereby broadening the applications of LSP in the fields of functional food. © 2021 Society of Chemical Industry.

Fabrication, characterization and functional attributes of zein-egg white derived peptides (EWDP)-chitosan ternary nanoparticles for encapsulation of curcumin: Role of EWDP

The food-derived peptides hydrolyzed from native food protein matrix exhibited various bioactivities and multimeric structures, which make them the promising well-defined nanoplatforms candidates to co-deliver themselves with other bioactive compounds. In this study, zein-egg white derived peptides-chitosan (Z-EWDP-CS) ternary nanoparticles (NPs) were successfully fabricated by the spontaneous assembly to enhance the stability and bioactivity of curcumin (Cur). The novel ternary NPs exhibited a typical nano-spherical structure (138.63 nm, 40.50 mV), and adorable encapsulation efficiency (EE, 93.87%) for Cur. FTIR, XRD and DSC results verified that Cur changed from a crystalline state to an amorphous state, and was successfully entrapped in the cavity of Z-EWDP-CS NPs. Furthermore, the thermal stability, photochemical stability, salt stability, and antioxidant activity were considerably improved in the NPs after the addition of EWDP. Our results demonstrate that the food-derived peptides could be an ideal affinity agent for the co-delivery of themselves with hydrophobic nutraceuticals.

Entrapment of curcumin in soy protein isolate using the pH-driven method: Nanoencapsulation and formation mechanism

The use of curcumin in the food industry is constrained by its poor aqueous dispersibility and instability. Previous studies have shown that stable curcumin nanoparticles can be prepared using a pH-driven method. In this study, the nanoencapsulation of curcumin by soybean protein isolate (SPI) was achieved using the pH-driven method. The effect of final pH on SPI and SPI-curcumin (SPI-Cur) nanocomposites was determined by analyzing the encapsulation efficiency and stability. SPI had a high encapsulation efficiency for curcumin and was stable, especially at pH 7 and 8. The formation mechanisms of SPI and SPI-Cur were further determined by molecular docking and multispectral analyses. The results showed that hydrogen bond acceptors (O−) of curcumin under alkaline media interacted with the donor groups (N–H) of amino acids to form hydrogen bonds. Throughout the process, hydrophobic interactions promoted the formation of the nanocomposites, and curcumin had a strong static fluorescence quenching effect on SPI. Furthermore, CD spectroscopy demonstrated that the pH-driven method altered the secondary structure of the SPI. This study provides evidence for the interaction mechanism between curcumin and SPI at different pH-driven stages and indicates SPI-Cur can be used as a delivery system of hydrophobic nutraceuticals.

Impact of composite gelators on physicochemical properties of oleogels and astaxanthin delivery of oleogel-based nanoemulsions

In this study, binary systems of carnauba wax (CW) and 1-docosanol (DS) were first explored to enhance the properties of oleogels. Compared to the corresponding single component oleogels (0:5 and 5:0), a synergistic effect of oleogel strength was observed at CW:DS ratios of 1:4 (C1D4). At this ratio, the formed oleogel showed the highest hardness, rheological property and oil binding ability. Meanwhile, the gel-sol melting temperature of this oleogel at this ratio was lower than most of others. Subsequently, the effect of composite gelators on the astaxanthin delivery of oleogel-based nanoemulsion was explored. The oleogels at CW:DS ratios of 1:4, 0:5 and 5:0 were chosen to prepare oleogel-based nanoemulsions. The oleogel-based nanoemulsion formulated with C1D4 had the largest droplet size. In vitro digestion study revealed that although C1D4 oleogel-based nanoemulsion could not improve the extent of lipolysis, it could significantly improve astaxanthin bioaccessibility when compared with the other two oleogel-based nanoemulsions. This study developed a new formula of oleogel-based nanoemulsion with improved astaxanthin bioaccessibility. This novel formulation approach might also be suitable for other hydrophobic nutraceuticals and provided a new idea for the preparation of oleogel-based nanoemulsions with improved nutraceutical bioaccessibility.

Impact of excipient emulsions made from different types of oils on the bioavailability and metabolism of curcumin in gastrointestinal tract

Low bioavailability currently limits the potential of curcumin as a health-promoting dietary compound. This study therefore explored the potential of excipient emulsions to improve curcumin bioavailability. Oil-in-water excipient emulsions were prepared using different types of oils: corn oil, olive oil, and medium chain triglycerides (MCT). The excipient emulsions increased the transportation rate of curcumin across the Caco-2 cell monolayer and showed ability to protect curcumin from metabolism in the enterocytes, with the olive oil-based systems exhibiting the highest efficacy. In addition, most of curcumin metabolites were present as hexahydro-curcumin (HHC) and its conjugates. Our results show that excipient emulsions can improve curcumin bioavailability by increasing its trans-enterocyte absorption and reducing cellular metabolism. Moreover, they show that these effects depend on the type of oil used to produce them. These findings have important implications for the rational design of lipid-based delivery systems to enhance the bioavailability of hydrophobic nutraceuticals like curcumin.

Multi-frequency ultrasound-assisted dialysis modulates the self-assembly of alcohol-free zein-sodium caseinate to encapsulate curcumin and fabricate composite nanoparticles

Developing a number of zein distribution mechanisms that encapsulate hydrophobic nutraceuticals has become a hot topic in food industry. In this study, the multi-frequency ultrasound-assisted dialysis method was used to fabricate stable nanoparticles. The ultrasound working mode and sodium caseinate modulated physicochemical properties, molecular interactions and microstructure of the nanoparticles system. The optimal ultrasonic frequency of 20/40 kHz resulted in Zein-sodium caseinate particle size, zeta potential and PDI values of 225.94 ± 3.84 nm, - 29.97 ± 1.49 mv, and the 0.19 ± 0.08, respectively. Additionally, ultrasound and Sodium Caseinate have a synergistic effect in improving the storage stability of nanoparticles. The results of fluorescence and CD demonstrated that ultrasound promoted the interaction between Sodium Caseinate and zein, by changing the local microenvironment and structure of the protein. FTIR results showed that the dominant driving force in the formation of hybrid nanoparticles was hydrophobic interaction, hydrogen bond and electrostatic interaction. Ultrasound-assisted dialysis was an effective strategy to encapsulate curcumin. XRD showed that curcumin was successfully encapsulated, and the 20/40 kHz ultrasound frequency combination improved encapsulation rate by 90.19 ± 0.33% as well as thermal stability, storage stability and antioxidant activity of curcumin (86.91 ± 0.72%). AFM and SEM showed uniform and regular spherical structure of composite nanoparticles. The findings revealed not only the multi-mode ultrasound assisted dialysis could be utilized to encapsulate hydrophobic bioactive compounds, which constructed delivery system, but also it provided a controlled release under simulated gastrointestinal conditions, and a better protection and desirable sustained-release of hydrophobic nutraceuticals.

Bioavailability of quercetin in zein-based colloidal particles-stabilized Pickering emulsions investigated by the in vitro digestion coupled with Caco-2 cell monolayer model

Protein-based Pickering emulsions have received considerable attention as nutraceutical vehicles. However, the oral bioavailability of nutraceuticals encapsulated in Pickering emulsions was not well established. In this work, a simulated gastrointestinal tract/Caco-2 cell culture model was applied to investigate the oral bioavailability of quercetin encapsulated in zein-based Pickering emulsions with quercetin in zein particles as the control. Pickering emulsions with shell (ZCP-QE) and core quercetin (ZCPE-Q) were constructed, and quercetin bioaccessibility, cell uptake and secretion, and the overall bioavailability were evaluated and compared. The overall oral bioavailability of quercetin was increased from 2.71% (bulk oil) to 38.18% (ZCPs-Q) and 18.97% (ZCPE-Q), particularly reached 41.22% for ZCP-QE. This work took new insights into the contributions of bioaccessibility and absorption (cell uptake plus secretion) to the overall oral bioavailability of quercetin. A schematic representation is proposed to relate the types of colloidal nanostructures in the digesta to the uptake, cell absorption, and overall oral bioavailability of quercetin. This study provided an attractive basis for identifying effective strategies to improve the oral bioavailability of hydrophobic nutraceuticals.

Nutraceutical-fortified plant-based milk analogs: Bioaccessibility of curcumin-loaded almond, cashew, coconut, and oat milks

Plant-based milk analogs often contain oil bodies, which are natural colloidal particles comprising of a triglyceride-rich core coated by a phospholipid/protein shell. Hydrophobic nutraceuticals, such as curcumin, can be encapsulated within these oil bodies utilizing a simple pH-driven method. Previously, we loaded curcumin into the oil bodies in soymilk using this approach. Here, we show this method is highly versatile and can be utilized to incorporate curcumin into other plant-based milk analogs (coconut, cashew, almond, and oat milks). Initially, the impact of pH-driven loading on the physicochemical attributes of the milk analogs was investigated. Curcumin bioaccessibility in the milk analogs was then ascertained using a simulated gastrointestinal tract. Curcumin was successfully loaded into all the milk analogs without causing adverse effects on oil body properties or stability. Curcumin had a high encapsulation efficiency (>86%) in all milk analogs, which was attributed to its localization inside the oil bodies. The curcumin-loaded plant-based milks had fairly similar bioaccessibilities (>60%), which were much higher than those seen for a crystalline form of the curcumin (about 5%). The information obtained may be utilized to facilitate the creation of the next-generation of nutritionally fortified plant-based milk analogs.

In vitro and in vivo study of the enhancement of carotenoid bioavailability in vegetables using excipient nanoemulsions: Impact of lipid content

The impact of lipid content of excipient nanoemulsions on the bioavailability of carotenoids from spinach was assessed using a combination of in vitro and in vivo digestion models. Alterations in the particle size, charge, microstructure, and lipid digestion were monitored as the spinach-nanoemulsion mixtures passed through the digestive tract. There was an increase in both bioaccessibility (19.2% > 14.4% > 7.5% > 3.1%) and bioavailability (106.7 > 39.6 ≈ 35.3 > 15.0 ng/mL) of carotenoids with increasing lipid content (1.0, 0.6, 0.2, 0 g), which attributed to higher transfer efficiency of the carotenoids from spinach to fat droplets and mixed micelles in increasing lipid content. The polarity of carotenoids also had an important impact: the bioavailability of lutein was significantly higher than that of β-carotene. Our findings show the importance of selecting an appropriate lipid content of reduced-fat emulsion-based foods to enhance the oral bioavailability of co-ingested hydrophobic nutraceuticals.

Novel γ-cyclodextrin-metal–organic frameworks for encapsulation of curcumin with improved loading capacity, physicochemical stability and controlled release properties

A safe and biodegradable γ-cyclodextrin-metal–organic-frameworks (γ-CD-MOFs) was successfully synthesized by using an improved hydrothermal method. In this study, curcumin (Cur) was chosen for testing the encapsulation stability and release performance of γ-CD-MOFs. Results of the crystal structure measurement indicated that the encapsulated curcumin within γ-CD-MOFs via van der Waals forces, hydrophobic interactions and hydrogen bonding was failed to disturb the inherent microtopography and crystallinity of γ-CD-MOFs. Compared to individual γ-CD, the γ-CD-MOFs exhibited improved loading capacity, physicochemical stability as well as controlled-release property in simulated digestion, and hence can be regarded as effective carriers for curcumin. Curcumin-loaded γ-CD-MOFs with a Cur : γ-CD-MOFs mass ratio of 2:3 (Cur-CD-MOFs/3), which showed the highest encapsulation efficiency (67.31 ± 2.25%), improved physicochemical stability and controlled-release performance, was selected for further research and industrialization. Our results demonstrate that γ-CD-MOFs can be regarded as a promising novel carrier for the delivery of curcumin or other hydrophobic nutraceuticals.

Edible alginate/chitosan-based nanocomposite microspheres as delivery vehicles of omega-3 rich oils

A new series of alginate/chitosan-based nanocomposite microspheres was developed to achieve the maximum health benefit and to minimize the oxidation of omega-3 rich oils (flaxseed or fish oils). The nanocomposite microspheres incorporate curcumin (Cur) as natural antioxidant, and have been prepared using a three-step procedure (oil-in-water (o/w) emulsification, gelation and microencapsulation). The average particle size of Cur-free and Cur-loaded nanocomposites ranged between 139 and 153 nm. The presence of omega-3 rich oils in core of the formulated microspheres was confirmed by XRD and FTIR. Optical microscopy, stereo microscopy, SEM and AFM showed a spherical shape of the microspheres. Microencapsulation efficiency, oxidative stability, release profile of oils as well as the antioxidant and antibacterial activities were investigated. The results suggested that the microspheres could be applied as effective and safe edible vehicles for hydrophobic nutraceuticals like omega-3 rich oils with broad spectrum antibacterial activity.

Fabrication of pea protein nanoparticles with calcium-induced cross-linking for the stabilization and delivery of antioxidative resveratrol

In this study, pea protein isolate (PPI) nanoparticles were fabricated with calcium-induced cross-linking and the potential as a nano-carrier for protecting resveratrol (RES) from degradation as well as improving its antioxidant activities was investigated. Ca2+ ions concentration and pH value had significant impacts on the formation of PPI nanoparticles. Dissociation assays suggested that PPI nanoparticles were mainly formed and stabilized by Ca2+ ions induced salt-bridge, hydrophobic interaction, and hydrogen bonding. Encapsulation efficiency (EE) and Loading amount (LA) of RES in PPI nanoparticles was 74.08%, and 30.24 μg/mg protein, respectively. Fluorescence emission results suggested that the formation of RES-PPI nanoparticles was primarily driven with hydrophobic interaction. AFM results clearly indicated that both RES-PPI nanocomplexes and RES-PPI nanoparticles were nano-scale, spherical shaped and distributed uniformly. RES-PPI nanoparticles exhibited higher physicochemical stability (Z-average diameter stability and RES retention) than RES-SPI nanocomplexes. Antioxidant ability of RES can be remarkably enhanced with both PPI-based nano-delivery systems. Ca2+ ions induced PPI nanoparticles obtained in this study have the great potential as functional delivery systems for hydrophobic nutraceuticals in food, and pharmaceutical industry.

Utilization of insect proteins to formulate nutraceutical delivery systems: Encapsulation and release of curcumin using mealworm protein-chitosan nano-complexes

The potential of using insect proteins to encapsulate and protect hydrophobic nutraceuticals within biopolymer nano-complexes was examined. Insect proteins were used to form nanoparticles that were uncoated or coated with chitosan. Initially, the nature of the curcumin-mealworm protein interaction was investigated. Curcumin mainly interacted with the hydrophobic core of the insect protein nanoparticles through hydrophobic forces. About one curcumin molecule bound per protein molecule in both the absence and presence of chitosan. The binding constants (K) were 1.1 × 104 M−1 and 0.7 × 104 M−1 for curcumin loaded in the uncoated and coated nanoparticles, respectively. Differential scanning calorimetry showed increased thermal stability of the proteins after interaction with curcumin or chitosan. Encapsulation efficiency of the curcumin within the biopolymer nano-complexes was 30–47% depending on the system. Transmission electron microscopy and dynamic light scattering analysis showed that the biopolymer nano-complexes were spherical and relatively small (d = 143–178 nm). FTIR suggests that curcumin was stabilized more effectively in the coated nano-complexes, due to non-covalent intermolecular interactions. Curcumin release under oral, gastric, and intestinal conditions showed that over 90% of the nutraceutical was released after exposure to model gastrointestinal conditions. The findings demonstrate the potential of using insect proteins for fabricating colloidal delivery systems for water-insoluble nutraceuticals.

Plant exine capsules based encapsulation strategy: A high loading and long-term effective delivery system for nobiletin.

The properties of high loading capacity and long-term absorption are of great significance in the field of nutraceuticals or drugs delivery. Herein, we developed an innovative method to achieve these expected effects using plant exine capsules, a kind of natural pollen grains, which could provide large internal cavities for loading and robust exine against harsh conditions. In our work, we firstly made a soluble mixture of glycerol monostearate (GM) and nobiletin (NOB) inside the cavities of plant exine capsules by ultrasound with high temperature to obtain a supersaturated state of NOB, which could be characterized by XRD, DSC and FTIR. After that, the loaded capsules were cooled to room temperature. Alginate hydrogels were then selected for encapsulating and further controlling NOB release in simulated gastric and intestinal conditions. As a result, it demonstrated that our approach was able to reach an extremely high NOB loading capacity of 770 ± 40 mg/g using sunflower pollen grains (SPGs). Meanwhile, the existence of GM, SPGs and alginate hydrogels all retarded the release of the NOB synergistically, thus taking a slow release effect in the stomach while a long-term effective absorption in the intestine. Taken together, our processing method of encapsulating hydrophobic nutraceuticals provides an important insight for broadening the applications of nutraceutical or drug encapsulation and delivery.

Green Formulation of Triglyceride/Phospholipid-Based Nanocarriers as a Novel Vehicle for Oral Coenzyme Q10 Delivery.

This study was aimed to develop a novel nanocarrier for coenzyme Q10 (CoQ10) by a green process that prevented the use of surfactants and organic solvents. Triglyceride/phospholipid-based nanocarriers were developed through high-pressure homogenization (an industrial feasible process), and a 25-1 fractional factorial design was adopted to assess the influences of formulation variables on the considered responses, including vesicle size, entrapment efficiency, loading capacity, and solubility of the vehicles in simulated gastrointestinal fluids. The optimized formulation was further in-depth characterized in terms of morphology, release behavior, biocompatibility (Caco-2 cell cytotoxicity and histological examination), thermal behavior, and Fourier transform infrared analysis. Optimal nanocarriers were found to have mean particle size of 75 nm, narrow particle distribution, and CoQ10 entrapment of 95%. The optimized formulation was stable upon incubation in simulated gastrointestinal fluids without considerable leakage of cargo, which was in agreement with their sustained release behavior. Microscopic observations also confirmed nanosized nature of the vesicles and revealed their spherical shape. Moreover, toxicity evaluations at the cellular and tissue levels revealed their nontoxic nature. In conclusion, triglyceride/phospholipid-based nanocarriers proved to be a green safe vehicle for delivery of CoQ10 with industrial-scale production capability and could provide a new horizon for delivery of hydrophobic nutraceuticals. PRACTICAL APPLICATION: Green nanostructure formulation approaches have recently gained tremendous attraction for their safe profile especially when it comes to supplements, which are generally recommended for daily use. However, their sufficient association with cargoes and industrial-scale production have remained considerable challenges. This study focuses on the development of lipid-based nanocarriers for CoQ10 by an industrial feasible process that prevents the use of any surfactants or organic solvents.

Zein-CMC-PEG Multiple Nanocolloidal Systems as a Novel Approach for Nutra-Pharmaceutical Applications.

Purpose: Hydrophobic nutraceuticals are suffering from water solubility and physicochemical stabilities once administered to the body or food matrixes. The present study depicts the successful formulation of a zein-carboxymethyl cellulose (CMC) complex to stabilize a water in oil (W/O) emulsion to protect them from environmental and gastrointestinal conditions. The formulated water in oil in water (W/O/W) system was used for nanoencapsulating of hydrophobic nutraceutical, rutin, via protein-polysaccharide complexes. Methods: Zein nano particles smaller than 100 nm were produced using poly ethylene glycol (PEG 400) and Tween 80, which eliminates the use of ethanolic solutions in preparation of zein nanoparticles (ZN). CMC was then added to the ZN under magnetic stirrer to provide zein-CMC complex. A concentration of 20% CMC showed the smallest particle size (<100 nm). Rutin was dispersed in water in oil in water (W/O/W) emulsion stabilized by zein-CMC complex. A set of experiments such as encapsulation efficiency (EE%), encapsulation stability (ES%), and releasing rate of rutin were measured during 30 days of storage at 4°C. Results: Results showed that, produced multiple emulsion prepared with lower concentrations of Tween 80 (0.5%), ethanol: PEG: water ratio of 0:80:20 showed smaller size (89.8±4.2 nm). ES% at pH values of 1.2, 6.8, and 7.4 were 86.63±6.19, 91.54±3.89, and 97.13±2.39 respectively, indicating high pH tolerability of formulated W/O/W emulsions. Conclusion: These findings could pave a new approach in stabilizing W/O/W emulsions for encapsulating and controlling the release of water insoluble nutraceuticals/drugs.

Novel Soy β-Conglycinin Core-Shell Nanoparticles As Outstanding Ecofriendly Nanocarriers for Curcumin.

The development of high-performance nanocarriers for nutraceuticals or drugs has become one of the topical research subjects in the functional food fields. In this work, we for the first time propose a novel and ecofriendly process to obtain a kind of nanostructured soy β-conglycinin (β-CG; a major soy storage globulin) as outstanding nanocarriers for poorly soluble bioactives (e.g., curcumin), by a urea-assisted disassembly and reassembly strategy. At urea concentrations > 4 M, the structure of β-CG gradually dissociated into its separate subunits (α, α', and β) and even denatured (depending on the type of subunits); after dialysis to remove urea, the dissociated subunits would reassemble into a kind of core-shell nanostructured particles, in which aggregated β-subunits acted as the core while the shell layer was mainly composed of α- and α'-subunits. The core-shell nanoparticles were favorably formed at protein concentrations of 1.0-2.0 wt %. Curcumin crystals were directly introduced into the β-CG solution at high urea concentrations (e.g., 8 M) and would preferentially interact with the denatured β-subunits. As a consequence, almost all of the curcumin molecules were encapsulated in the core part of the reassembled core-shell nanoparticles. The loading amount of curcumin in these nanoparticles could reach 18 g of curcumin per 100 g of protein, which far exceeds those reported previously. The encapsulated curcumin exhibited a high water solubility, extraordinary thermal stability, and improved bioaccessibility, as well as a sustained release behavior. The findings provide a novel strategy to fabricate a kind of high-encapsulation-performance, organic solvent-free, and biocompatible nanocarrier for hydrophobic nutraceuticals and drugs.