Construction of quaternary ammonium chitosan-coated protein nanoparticles as novel delivery system for curcumin: Characterization, stability, antioxidant activity and bio-accessibility

This research aimed to develop a novel, effective, and stable delivery system based on zein (ZE), sodium caseinate (SC), and quaternary ammonium chitosan (HACC) for curcumin (CUR). The pH-driven self-assembly combined with electrostatic deposition methods were employed to construct CUR-loaded ZE-SC nanoparticles with HACC coating (ZE-SC@HACC). The optimized nanocomposite was prepared at ZE:SC:HACC:CUR mass ratios of 1:1:2:0.1, and it had encapsulation efficiency of 89.3%, average diameter of 218.2 nm, and ζ-potential of 40.7 mV. The assembly of composites and encapsulation of CUR were facilitated primarily by hydrophobic, hydrogen-bonding, and electrostatic interactions. Physicochemical stability analysis revealed that HACC coating dramatically enhanced ZE-SC nanoparticles' colloidal stability and CUR's resistance to chemical degradation. Additionally, antioxidant activity and simulated digestion results indicated that CUR-ZE-SC@HACC nanoparticles showed higher free radical scavenging capacity and bio-accessibility of CUR than CUR-ZE-SC nanoparticles and free CUR. Therefore, the ZE-SC@HACC nanocomposite is an effective and viable delivery system for CUR.

Effects of different solid particle sizes on oat protein isolate and pectin particle-stabilized Pickering emulsions and their use as delivery systems

Oat protein isolate (OPI)/high methoxyl pectin (HMP) complexes (OPP) were prepared to stabilized Pickering emulsions and applied as nutraceutical delivery systems. The different mass ratios and pH changed the interactions between OPI and HMP that caused the different size of OPP. Specifically, smaller particle size of OPP (125.7-297.6 nm) were formed when hydrophobic interactions along with electrostatic forces predominant in OPP (OPI:HMP = 3:1, pH 4, 5). Among these particles, OPP-2 could stabilize Pickering emulsion efficiently through formation of dense interfacial film, which exhibited the highest apparent viscosity and the smallest average droplet size (23.39 μm). Moreover, OPP-2 stabilized Pickering emulsions with superior stability not only exhibited higher encapsulation efficiency of 85.63%, but also could control curcumin release in simulated gastrointestinal fluids to improve curcumin's bioaccessibility. These results verified the possibility of OPP to be a Pickering emulsions stabilizer, and also identified its potential to be a stable delivery system for bioactive compounds.

A capsule-based scaffold incorporating decellularized extracellular matrix and curcumin for islet beta cell therapy in type 1 diabetes mellitus

The transplantation of islet beta cells offers an alternative to heterotopic islet transplantation for treating type 1 diabetes mellitus (T1DM). However, the use of systemic immunosuppressive drugs in islet transplantation poses significant risks to the body. To address this issue, we constructed an encapsulated hybrid scaffold loaded with islet beta cells. This article focuses on the preparation of the encapsulated structure using 3D printing, which incorporates porcine pancreas decellularized extracellular matrix (dECM) to the core scaffold. The improved decellularization method successfully preserved a substantial proportion of protein (such as Collagen I and Laminins) architecture and glycosaminoglycans in the dECM hydrogel, while effectively removing most of the DNA. The inclusion of dECM enhanced the physical and chemical properties of the scaffold, resulting in a porosity of 83.62% ± 1.09% and a tensile stress of 1.85 ± 0.16 MPa. In teams of biological activity, dECM demonstrated enhanced proliferation, differentiation, and expression of transcription factors such as Ki67, PDX1, and NKX6.1, leading to improved insulin secretion function in MIN-6 pancreatic beta cells. In the glucose-stimulated insulin secretion experiment on day 21, the maximum insulin secretion from the encapsulated structure reached 1.96 ± 0.08 mIU ml-1, representing a 44% increase compared to the control group. Furthermore, conventional capsule scaffolds leaverage the compatibility of natural biomaterials with macrophages to mitigate immune rejection. Here, incorporating curcumin into the capsule scaffold significantly reduced the secretion of pro-inflammatory cytokine (IL-1β, IL-6, TNF-α, IFN-γ) secretion by RAW264.7 macrophages and T cells in T1DM mice. This approach protected pancreatic islet cells against immune cell infiltration mediated by inflammatory factors and prevented insulitis. Overall, the encapsulated scaffold developed in this study shows promise as a natural platform for clinical treatment of T1DM.

Co-encapsulation of borage seed oil and peppermint oil blends within ultrasound-assisted soy protein isolate/purity gum ultra complex nanoparticles: Fabrication, structural interaction mechanisms, and in vitro digestion studies

This study aimed at co-encapsulating borage seed oil (BSO)- and peppermint oil (PO) blends in ultrasound-assisted complex nanoparticles stabilized by soy protein isolate (SPI) and purity gum ultra (PGU) in different ratios: SPI/PGU-1:0 (NP1), 0:1 (NP2), 1:1 (NP3), 1:3 (NP4), and 3:1 (NP5). The BSO- and PO-loaded SPI/PGU complex nanoparticles (BP-loaded SPNPs) coded as NP4 (SPI-PGU-1:3) revealed a zeta potential of -33.27 mV, a PDI of 0.14, and the highest encapsulation efficiency (81.38 %). The main interactions observed among SPI, PGU, BSO, PO, and a blend of BSO and PO, as determined by FTIR and molecular docking, involved hydrophobic effects, electrostatic attraction, and H-bonding. These interactions played crucial roles in the production of BP-loaded SPNPs. XRD results validated the alterations in the structure of BP-loaded SPNPs caused by varying proportions of SPI and PGU. The thermal capacity of BP-loaded SPNPs (NP4), as determined by TGA, exhibited the lowest amount of weight loss compared to other BP-loaded SPNPs. Morphological results revealed that NP4 and NP5 exhibited a spherical surface and two distinguishable layers, indicating successful coating of PGU onto the droplet surface. In addition, BP-loaded SPNPs (NP4) exhibited a higher antioxidant effect due to their improved progressive release and prolonged release of co-encapsulated BSO and PO during in vitro digestion. The comprehensive investigation of the co-encapsulation of BSO and PO in complex nanoparticles, dietary supplements, and double-layered emulsified systems provides valuable insights into the development of functional foods.

Formation mechanism, prevention of malignant ascites effusion and reduction of intestinal mucosal irritation of natural microemulsion from Euphorbia lathyris Pulveratum

Malignant ascites effusion (MAE) is a common complication of advanced malignant tumors with limited treatments. Euphorbia lathyris (EL) has a long history of application in patients with edema and ascites. Herein, we reported for the first time a mode in which EL and EL Pulveratum (PEL) spontaneously formed natural microemulsions (ELM and PELM) without the addition of any carriers and excipients, and found that the protein and phospholipid contained in them encapsulated fatty oil and diterpenoid esters through non-covalent interactions. The denaturation and degradation of protein in PELM resulted in stronger binding of diterpenoid esters to the hydrophobic region of protein, which facilitated the sustained and slow release of diterpenoid esters and improved their bioavailability in vivo, thereby retaining the efficacy of preventing MAE while alleviating the irritation of intestinal mucosa. The mechanism by which PELM retained efficacy might be related to increased feces moisture and urine volume, and decreased expression of AVPR2, cAMP, PKA and AQP3 in MAE mice. And its mechanism of reducing intestinal mucosal irritation was related to decreased cell apoptosis, amelioration of oxidative stress, elevation of mitochondrial membrane potential, and up-regulation of Occludin and Claudin-1 expression in IEC-6 cells. This nano-adjuvant-free natural microemulsions may be a promising therapeutic strategy in the field of phytochemistry for promoting the application of natural and efficient nano-aggregates spontaneously formed by medicinal plants in MAE, and provide a new perspective for advancing the development of the fusion of Chinese herbal medicine and nanomedicine and its clinical translation.

Synthesis of Ganoderic Acids Loaded Zein-Chitosan Nanoparticles and Evaluation of Their Hepatoprotective Effect on Mice Given Excessive Alcohol

Ganoderma lucidum, used in East Asia for its health benefits, contains ganoderic acids (GA) which have various pharmacological activities but are limited by poor water solubility and low oral bioaccessibility. This study synthesized and characterized ganoderic acids loaded zein-chitosan nanoparticles (GA-NPs), and investigated its advantages in alleviating alcoholic liver injury (ALI) in mice model. The GA-NPs demonstrated high encapsulation efficiency (92.68%), small particle size (177.20 nm), and a +29.53 mV zeta potential. The experimental results of alcohol-induced liver injury mouse model showed that GA-NPs significantly improved liver metabolic function, reduced alcohol-induced liver oxidative stress in liver by decreasing lactate dehydrogenase activity and malondialdehyde level, while increasing the activities of liver antioxidant enzymes and alcohol dehydrogenase. Moreover, GA-NPs were favorable to ameliorate intestinal microbiota dysbiosis in mice exposed to alcohol by increasing the proportion of probiotics such as Romboutsia, Faecalibaculum, Bifidobacterium and Turicibacter, etc., which were highly correlated with the improvement of liver function. Furthermore, GA-NPs modulated the mRNA expression related to ethanol metabolism, oxidative stress and lipid metabolism. Conclusively, this study revealed that GA-NPs have stronger hepatoprotective effects than non-encapsulated ganoderic acids on alleviating ALI by regulating intestinal microbiota and liver metabolism.

Plant-Based Meat Analogues and Consumer Interest in 3D-Printed Products: A Mini-Review

The markets for plant-based meat analogues (PBMAs) are growing worldwide, showing the increasing consumer demand for and acceptance of these new products. Three-dimensional (3D) food printing is a new technology with huge potential for printing products customised to suit consumers' wants and needs. There is a broad acceptance from consumers regarding the safety and desirability of consuming food products that are produced using 3D printing. As this is a new technology, consumers must be provided with relevant information from a trusted source, with further research needing to be conducted within the context of the identified market and culture. By embracing the strength of customisation of 3D printing and coupling this with the global demand for plant-based products, 3D printed PBMAs could be a future challenger to the currently popular production method of extrusion. Therefore, this article reviews consumer interests in PBMAs and summarises opportunities for using 3D printing technology to produce plant-based meat analogues.

The pro-absorptive effect of glycosylated zein-fatty acid complexes on fucoxanthin via the lipid transporter protein delivery pathway

Growing research confirms that lipid transport proteins play a key role in the trans-intestinal epithelial transport of carotenoids. In this study, to simultaneously improve the digestive stability and intestinal absorption of fucoxanthin (FX), functionalized vectors with a capability of up-regulating the expression of FX-specific lipid transporter proteins was fabricated. The results showed that myristic acid, palmitic acid, and stearic acid effectively promoted FX-specific lipid transporter protein expression and formed stable self-assembly complexes with Millard-modified zein (MZ). The FX was sufficiently encapsulated in the MZ-fatty acid (FA) particles, forming spherical nanoparticles with a "core-shell" structure. Simulated gastrointestinal digestion showed that FA introduction significantly increased the FX bioaccessibility. In vivo results further verified that adding FAs dramatically increased the FX serum response concentration. These findings suggest that incorporating nutrients that can promote lipid transporter protein expression into delivery vehicles should be an effective strategy for improving oral carotenoid absorption.

Apple pectin-based active films to preserve oil: Effects of naturally branched phytoglycogen-curcumin host

Pectin has excellent film-forming properties, but its functional properties need to be enhanced. Therefore, we constructed naturally branched phytoglycogen (PG) nanoparticles to solubilize curcumin (CCM) and further enhance the properties of apple pectin-based active films. The size of the PG spherical particles ranged from 30 to 100 nm with some aggregates. The branch density of the PG was 6.02 %. These PG nanoparticles increased the solubility of CCM nearly 1742-fold and a nanosized phytoglycogen-curcumin (PG-CCM) host was formed via hydrogen bonding and hydrophobic interaction. This host promoted the formation of pectin-based films with a dense structure and increased their tensile strength to 23.51 MPa. The coefficient to water vapor permeability, oxygen permeability and carbon dioxide permeability were all decreased indicating their barrier performance were improved. Among them, the oxygen permeability coefficient decreased most, from 1.14 × 10-7 g·m-1·s-1 to 0.8 × 10-7 g·m-1·s-1. Also, the transmittance of the active film at 280 nm and 660 nm decreased to 0.65 % and 72.10 %. Antioxidant and antibacterial properties were significantly enhanced (P < 0.05). And the results showed this film was an excellent oil packaging material. The active film incorporating PG-CCM host can replace heat-sealed plastic bags/pouch made from polyethylene and polypropylene synthetic plastics, and solve the problem that plastic packaging is difficult to degrade and cannot be squeezed clean. This provides a new conceptual framework for developing pectin-based active films by incorporating of PG and CCM.

Injectable, self-healing hydrogels based on gelatin, quaternized chitosan, and laponite as localized celecoxib delivery system for nucleus pulpous repair

Utilization of injectable hydrogels stands as a paradigm of minimally invasive intervention in the context of intervertebral disc degeneration treatment. Restoration of nucleus pulposus (NP) function exerts a profound influence in alleviating back pain. This study introduces an innovative class of injectable shear-thinning hydrogels, founded on quaternized chitosan (QCS), gelatin (GEL), and laponite (LAP) with the capacity for sustained release of the anti-inflammatory drug, celecoxib (CLX). First, synthesis of Magnesium-Aluminum-Layered double hydroxide (LDH) was achieved through a co-precipitation methodology, as a carrier for celecoxib and a source of Mg ions. Intercalation of celecoxib within LDH layers (LDH-CLX) was verified through a battery of analytical techniques, including FTIR, XRD, SEM, EDAX, TGA and UV-visible spectroscopy confirmed a drug loading efficiency of 39.22 ± 0.09 % within LDH. Then, LDH-CLX was loaded in the optimal GEL-QCS-LAP hydrogel under physiological conditions. Release behavior (15 days profile), mechanical properties, swelling ratio, and degradation rate of the resulting composite were evaluated. A G* of 15-47 kPa was recorded for the hydrogel at 22-40 °C, indicating gel stability in this temperature range. Self-healing properties and injectability of the composite were proved by rheological measurements. Also, ex vivo injection into intervertebral disc of sheep, evidenced in situ forming and NP cavity filling behavior of the hydrogel. Support of GEL-QCS-LAP/LDH-CLX (containing mg2+ ions) for viability and proliferation (from ~94 % on day 1 to ~134 % on day 7) of NP cells proved using MTT assay, DAPI and Live/Dead assays. The hydrogel could significantly upregulate secretion of glycosaminoglycan (GAG, from 4.68 ± 0.1 to 27.54 ± 1.0 μg/ml), when LHD-CLX3% was loaded. We conclude that presence of mg2+ ion and celecoxib in the hydrogel can lead to creation of a suitable environment that encourages GAG secretion. In conclusion, the formulated hydrogel holds promise as a minimally invasive candidate for degenerative disc repair.

Multi-spectroscopies and molecular docking insights into the interaction mechanism and antioxidant activity of isoquercetin and zein nanoparticles

The purpose of this study was to compare and characterize the theoretical properties and interaction mechanisms of zein and isoquercetin (ISO) from experimental and theoretical perspectives. Zein nanoparticles with different ISO concentrations (ZINPs) were prepared by the antisolvent precipitation method. The experimental results indicated all particles appeared spherical. When the mass ratio of zein to ISO was 10:1, the encapsulation efficiency of ZINPs reached 88.19 % with an average diameter of 126.67 nm. The multispectral method and molecular docking results confirmed that hydrogen bonding and van der Waals force played a dominant role for the binding of ISO to zein, and the primary fluorescence quenching mechanism for zein by ISO was static quenching. Furthermore, ZINPs had greater solubility and antioxidant activity, as well as inhibited the release of ISO during simulated gastrointestinal digestion processes. This research contributes to the understanding of the non-covalent binding mechanism between zein and ISO, providing a theoretical basis for the construction of ISO active carriers.

Fabrication of Citrus bergamia essential oil-loaded sodium caseinate/peach gum nanocomplexes: Physicochemical, spectral, and structural characterization

`The objective of current research was to encapsulate citrus bergamia essential oil (CBEO) in nanocomplexes composed of sodium caseinate (SC) and peach gum polysaccharide (PG) in various ratios (SC/PG-1:0, 0:1, 1:1, 1:3, and 3:1). The nanocomplexes formed by the combination of SC and PG in a ratio of 1:3 exhibited a zeta potential of -21.36 mV and a PDI of 0.25. The CBEO-loaded SC/PG (1:3) nanocomplexes revealed the maximum encapsulation efficiency (82.47 %) and loading capacity (1.85 %). FTIR also confirmed the secondary structure variations in response to different ratios of CBEO-loaded SC/PG nanocomplexes. In addition, the XRD and fluorescence spectroscopy analysis also revealed structural changes among CBEO nanocomplexes. The thermal capability of CBEO-loaded SC/PG (1:3) nanocomplexes via TGA showed the minimum weight loss among other complexes. SEM and CLSM analysis demonstrated the uniform distribution and spherical morphology of CBEO-loaded SC/PG (1:3) nanocomplexes. The antioxidant activity of free CBEO was significantly improved in CBEO-loaded nanocomplexes. Likewise, the inhibitory activity of CBEO-loaded nanocomplexes exhibited significantly higher antibacterial action against S. aureus and E. coli. The aforementioned perspective suggests that SC/PG nanocomplexes have potent potential to serve as highly effective nanocarriers with a broad spectrum of uses in the pharmaceutical and food sectors.

Exploration of the structural mechanism of hydrogen (H2)-promoted horseradish peroxidase (HRP) activity via multiple spectroscopic and molecular dynamics simulation techniques

Horseradish peroxidase (HRP) is an enzyme that is widely used in various fields. In this study, the effects of molecular hydrogen (H2) on the activity and structural characteristics of HRP were investigated by employing multiple spectroscopic techniques, atomic force microscopy (AFM) and molecular dynamics (MD) simulations. The results demonstrated that H2 could enhance HRP activity, especially in 1.5 mg/L hydrogen-rich water (HRW). The structural analysis results showed that H2 might alter HRP activity by affecting the active sites, secondary structure, hydrogen bonding network, CS groups, and morphological characteristics. The MD results also confirmed that H2 could increase the FeN bond distance in the active site, affect the secondary structure, and increase the number of hydrogen bonds. The MD results further suggested that H2 could increase the number of salt bridges, and lengthen the SS bonds in HRP. This study primarily revealed the mechanism by which H2 enhances the HRP activity, providing insight into the interactions between gas and macromolecular proteins. However, some of the results obtained via MD simulations still need to be verified experimentally. In addition, our study also provided a new convenient strategy to enhance enzyme activity.

The role of polysaccharides in improving the functionality of zein coated nanocarriers: Implications for colloidal stability under environmental stresses

Zein has gained popularity over the past few years as an incredible food and bio-based materials. The potential functions and health benefits of zein microcapsules or micro-/nanoparticles in bioactive components delivery, structured emulsion, etc., have received great attention. However, the development has been limited by colloidal destabilization, especially when thermal processing is involved. There is a recent trend in developing zein-polysaccharide complexes (ZPCs), which has tremendously improved the performance of zein-based colloidal carrier systems or emulsions. Increasing our understanding of zein interactions and their contribution to the structure of various macromolecules can help us to develop novel biomaterials that can be used in food, agriculture, biomedicine, and cosmetics. In addition, these nanocarriers are suitable for the encapsulation and delivery of bioactive compounds which have positive perspective in food industry. Therefore, this article aimed to review recent advances in the ZPCs that can be applied to functional or health-promoting foods, with a focus on the characteristics of different ZPCs, factors and mechanisms affecting the stability (especially thermal stability) of these complexes, and their application in food industry as a carrier for BCs. Further, the stability of ZPCs based emulsions under processing and physiological environments, as well some typical effective methods are introduced. Also, the principal challenges and prospects were enumerated and discussed.

Improved antioxidant activity and delivery of peppermint oil Pickering emulsion stabilized by resveratrol-grafted zein covalent conjugate/quaternary ammonium chitosan nanoparticles

Novel nanoparticles (Z-R/H) were successfully fabricated by a resveratrol-grafted zein covalent conjugate (Z-R) combined with quaternary ammonium chitosan (HTCC), which were used as stabilizers to prepare peppermint oil (PO) Pickering emulsions with antioxidant activity. HTCC effectively adjusted wettability of Z-R conjugate, and three-phase contact angle of Z-R/H3:1 was moderate (95.01°). The influencing factors of Pickering emulsion formation, including volume fraction of PO, concentration of Z-R/H, and mass ratio of Z-R to HTCC, were evaluated by droplet size, ζ-potential, microscopic observation, and stability index analysis. Pickering emulsions stabilized by Z-R/H3:1 showed excellent physical stability under heat treatment. Z-R/H nanoparticles adsorbed on the oil-water interface yielded a dense filling layer as a physical barrier to improve the emulsion stability, which was validated by confocal laser-scanning microscopy. After 4 weeks of storage, retention rate of PO in Pickering emulsion stabilized by Z-R/H3:1 remained high (72.1 %). Electronic nose analysis showed that Z-R/H3:1-stabilized emulsion effectively prevented volatilization of PO aroma components. Additionally, PO and Z-R/H nanoparticles provided an additive antioxidant effect of Pickering emulsions against DPPH and ABTS free radicals. In summary, these novel Z-R/H nanoparticle offer promising applications as a stabilizer with great potential in preparing functional Pickering emulsions to improve essential oil delivery.

A curcumin oral delivery system based on sodium caseinate and carboxymethylpachymaran nanocomposites

The food industry has paid lots of attentions to curcumin because of its potential bioactive qualities. However, its use is severely constrained by its low bioavailability, stability and water solubility. Herein, we created sodium caseinate and carboxymethylpachymaran (CMP) nanoparticles (SMCNPs) that were loaded with curcumin. The composite nanoparticles were spherical, as characterized by SEM and TEM, the fluorescence spectroscopy, FTIR and XRD research revealed that hydrogen bonding, hydrophobic interaction and electrostatic interaction were the main drivers behind the creation of the nanoparticles. The SMCNPs exhibited lower particle size, greater dispersion and higher encapsulation rate when the mass ratio of sodium caseinate to CMP was 3:5 (particle size of 166.8 nm, PDI of 0.15, and encapsulation efficiency of 88.07 %). The composite nanoparticles had good antioxidant activity, physical stability and sustained release effect on intestinal tract during the in vitro simulation experiments, successfully preventing the early release of curcumin into gastric fluid. Finally, cytotoxicity studies told that the prepared composite nanoparticles have good biocompatibility and can inhibit the growth of tumor cells (HT-29). In conclusion, using CMP and sodium caseinate as carriers in this study may open up a fresh, environmentally friendly, and long-lasting way to construct a bioactive material delivery system.

Improving stability and bioavailability of curcumin by quaternized chitosan coated nanoemulsion

This study aims to enhance the stability and bioavailability of curcumin (Cur) using nanoemulsion coating technology. The nanoemulsion system was developed by encapsulating Cur with quaternized chitosan (QMNE), and the nanoemulsion containing Cur and medium-chain triglyceride (MCT) oil (MNE) was used as control sample. The microstructure of the nanoemulsion was examined using Dynamic light scattering (DLS), Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR). The storage, thermal, ionic strength, and pH stability of QMNE were also evaluated, respectively. The results indicate that QMNE demonstrates superior stability, in vitro gastric fluid stability, bioavailability compared to MNE. QMNE exhibits excellent emulsification activity and stability. In addition, QMNE shows significant protection against oxidation in both emulsion systems after different heat treatments. The antimicrobial activity results reveal that QMNE exhibits greater efficacy than that of MNE. Consequently, this study provides valuable insights into the formulation of a system to encapsulate Cur and the improvement of its stability and bioavailability.

One-Pot Self-Assembly of Core-Shell Nanoparticles within Fibers by Coaxial Electrospinning for Intestine-Targeted Delivery of Curcumin

Nanotechniques for curcumin (Cur) encapsulation provided a potential capability to avoid limitations and improve biological activities in food and pharmaceutics. Different from multi-step encapsulation systems, in this study, zein-curcumin (Z-Cur) core-shell nanoparticles could be self-assembled within Eudragit S100 (ES100) fibers through one-pot coaxial electrospinning with Cur at an encapsulation efficiency (EE) of 96% for ES100-zein-Cur (ES100-Z-Cur) and EE of 67% for self-assembled Z-Cur. The resulting structure realized the double protection of Cur by ES100 and zein, which provided both pH responsiveness and sustained release performances. The self-assembled Z-Cur nanoparticles released from fibermats were spherical (diameter 328 nm) and had a relatively uniform distribution (polydispersity index 0.62). The spherical structures of Z-Cur nanoparticles and Z-Cur nanoparticles loaded in ES100 fibermats could be observed by transmission electron microscopy (TEM). Fourier transform infrared spectra (FTIR) and X-ray diffractometer (XRD) revealed that hydrophobic interactions occurred between the encapsulated Cur and zein, while Cur was amorphous (rather than in crystalline form). Loading in the fibermat could significantly enhance the photothermal stability of Cur. This novel one-pot system much more easily and efficiently combined nanoparticles and fibers together, offering inherent advantages such as step economy, operational simplicity, and synthetic efficiency. These core-shell biopolymer fibermats which incorporate Cur can be applied in pharmaceutical products toward the goals of sustainable and controllable intestine-targeted drug delivery.

Delivery of curcumin by shellac encapsulation: Stability, bioaccessibility, freeze-dried redispersibility, and solubilization

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Shellac can nano-encapsulate curcumin by pH cycle.

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The starting point of the design is economy, simplicity, energy saving and safety.

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High loading capacity of curcumin is the unique advantage of shellac nanoparticles.

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The nanoparticles had good physicochemical stability and bioaccessibility.

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The redispersibility is proportional to the mass ratio of shellac-to-curcumin.

Curcumin is an active ingredient with multiple functions, however, its application is limited by its low stability, bioaccessibility, freeze-dried redispersibility, and solubilization. The work aims to improve the application of curcumin (Cur) by encapsulation. Shellac was the wall material inspired by its pH-dependent deprotonation and amphiphilic nature to form nanoparticles. The curcumin/shellac nanoparticles (S/Cur) exhibited a bright spot of high loading capacity (the maximum of higher than 70 %), while still having high encapsulation efficiency (the minimum of higher than 85 %). Transmission electron microscopy showed that S/Cur was a spherical structure. It exhibited good physical stability, including pH (4.0–8.0), ionic strength (NaCl, < 900 mM), thermo stability (80 ℃, 180 min), and storage stability (light and dark, 4 and 25 ℃, 20 days). Meanwhile, the chemical stability was increased by encapsulation. Furthermore, the bioaccessibility of Cur was improved to 75.95 %, which is attributed to the pH response of shellac. Additionally, S/Cur had freeze-dried redispersibility and solubilization, which is proportional to the mass ratio of shellac-to-Cur. The mechanism of S/Cur formation involved hydrophobic interaction and hydrogen bonds, and the nanoconfined Cur was amorphous.

Zein-based nano-delivery systems for encapsulation and protection of hydrophobic bioactives: A review

Zein is a kind of excellent carrier materials to construct nano-sized delivery systems for hydrophobic bioactives, owing to its unique interfacial behavior, such as self-assembly and packing into nanoparticles. In this article, the chemical basis and preparation methods of zein nanoparticles are firstly reviewed, including chemical crosslinking, emulsification/solvent evaporation, antisolvent, pH-driven method, etc., as well as the pros and cons of different preparation methods. Various strategies to improve their physicochemical properties are then summarized. Lastly, the encapsulation and protection effects of zein-based nano-sized delivery systems (e.g., nanoparticles, nanofibers, nanomicelles and nanogels) are discussed, using curcumin as a model bioactive ingredient. This review will provide guidance for the in-depth development of hydrophobic bioactives formulations and improve the application value of zein in the food industry.

Encapsulation of EGCG by Zein-Gum Arabic Complex Nanoparticles and In Vitro Simulated Digestion of Complex Nanoparticles

Epigallocatechin gallate (EGCG) has many excellent qualities such as its antitumor, antiradiation and anti-oxidation properties, but its application is limited because its oral bioavailability is low and stability is poor. In this paper, zein and gum arabic (GA) were used as wall materials to prepare Zein-GA complex nanoparticles for encapsulating and protecting the EGCG. The particle size of Zein-GA-EGCG complex nanoparticles ranged from 128.03–221.23 nm, and the EGCG encapsulation efficiency reached a maximum of 75.23% when the mass ratio of zein to GA was 1:1. The FTIR and XRD results illustrated that the components of the Zein-GA-EGCG complex nanoparticles interacted by electrostatic, hydrogen bonding, and hydrophobic interactions. The EGCG release rate of Zein-GA-EGCG nanoparticles (16.42%) was lower than that of Zein-EGCG (25.52%) during gastric digestion, and a large amount of EGCG was released during intestinal digestion, suggesting that the Zein-GA-EGCG nanoparticles could achieve the sustained release of EGCG during in vitro digestion. Hence, using Zein-GA complexes to encapsulate EGCG effectively increased the encapsulation efficiency of EGCG and realized the purpose of sustained release during simulated gastrointestinal digestion.

Zein Microparticles and Nanoparticles as Drug Delivery Systems

Zein is a natural, biocompatible, and biodegradable polymer widely used in the pharmaceutical, biomedical, and packaging fields because of its low water vapor permeability, antibacterial activity, and hydrophobicity. It is a vegetal protein extracted from renewable resources (it is the major storage protein from corn). There has been growing attention to producing zein-based drug delivery systems in the recent years. Being a hydrophobic biopolymer, it is used in the controlled and targeted delivery of active principles. This review examines the present-day landscape of zein-based microparticles and nanoparticles, focusing on the different techniques used to obtain particles, the optimization of process parameters, advantages, disadvantages, and final applications.

An updated and comprehensive review on the potential health effects of curcumin-encapsulated micro/nanoparticles

Curcumin (CUR) is a natural hydrophobic compound, which is available in turmeric rhizome. It has several bioactivities including antioxidant, anti-obesity, anti-diabetic, cardioprotective, anti-inflammatory, antimicrobial, anticancer, and other activities. Despite its medical and biological benefits, it is using in limitations because of its hydrophobicity and sensitivity. These unfavorable conditions further reduced the bioavailability (BA) and biological efficacy of CUR. This review summarizes the stability and BA of free- and encapsulated-CUR, as well as comprehensively discusses the potential biological activity of CUR-loaded various micro-/nano-encapsulation systems. The stability and BA of CUR can be improved via loading in different encapsulation systems, including nanoemulsions, liposomes, niosomes, biopolymer-based nanoparticles, nano-hydrogel, and others. Biopolymer-based nanoparticles (especially poly lactic-co-glycolic acid (PLGA), zein, and chitosan) and nano-gels are the best carriers for encapsulating and delivering CUR. Both delivery systems are suitable because of their excellent functional properties such as high encapsulation efficiency, well-stability against unfavorable conditions, and can be coated using other encapsulation systems. Based on available evidences, encapsulated-CUR exerted greater biological activities especially anticancer (breast cancer), antioxidant, antidiabetic, and neuroprotective effects.

Single-Step Self-Assembly of Zein–Honey–Chitosan Nanoparticles for Hydrophilic Drug Incorporation by Flash Nanoprecipitation

Zein- and chitosan-based nanoparticles have been described as promising carrier systems for food, biomedical and pharmaceutical applications. However, the manufacture of size-controlled zein and chitosan particles is challenging. In this study, an adapted anti-solvent nanoprecipitation method was developed. The effects of the concentration of zein and chitosan and the pH of the collection solution on the properties of the zein–honey–chitosan nanoparticles were investigated. Flash nanoprecipitation was demonstrated as a rapid, scalable, single-step method to achieve the self-assembly of zein–honey–chitosan nanoparticles. The nanoparticles size was tuned by varying certain formulation parameters, including the total concentration and ratio of the polymers. The zein–honey–chitosan nanoparticles’ hydrodynamic diameter was below 200 nm and the particles were stable for 30 days. Vitamin C was used as a hydrophilic model substance and efficiently encapsulated into these nanoparticles. This study opens a promising pathway for one-step producing zein–honey–chitosan nanoparticles by flash nanoprecipitation for hydrophilic compounds’ encapsulation.

A Novel Hyaluronic Acid-Black Rice Anthocyanins Nanocomposite: Preparation, Characterization, and Its Xanthine Oxidase (XO)-Inhibiting Properties

To promote the normal metabolism of human uric acid, high-performance hyaluronic acid-black rice anthocyanins (HAA) nanocomposite particles were successfully prepared by a simple crosslinking method as a novel xanthine oxidase inhibitor. Its structure and properties were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FT-IR), and X-ray diffraction (XRD). SEM and TEM electron microscopy showed an obvious double-layer spherical structure with a particle size of ~298 nm. FT-IR and XRD analysis confirmed that black rice anthocyanins (ATC) had been successfully loaded into the hyaluronic acid (HA) structure. Nanocomposite particles (embedded form) showed higher stability in different environments than free black rice ATC (unembedded form). In addition, the preliminary study showed that the inhibition rate of the nanocomposite particles on Xanthine oxidase (XO) was increased by 40.08%. These results indicate that HAA nanocomposite particles can effectively improve black rice ATC's stability and activity, creating an ideal new material for inhibiting XO activity that has a broad application prospect.

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

BACKGROUND

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.

RESULTS

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.

CONCLUSION

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.

Delivery of Curcumin Using Zein-Gum Arabic-Tannic Acid Composite Particles: Fabrication, Characterization, and in vitro Release Properties

The application of curcumin (Cur) in fat-free food is limited due to its poor water solubility, stability, and bioaccessibility. In this study, zein-gum arabic-tannic acid (zein-GA-TA) composite particles with high physical stability were fabricated to deliver Cur (ZGT-Cur). Their stability and in vitro release properties were also evaluated. The results showed that the thermal and photochemical stability of Cur was improved after loading into composite particles. Meanwhile, the retention rate of Cur in ZGT-Cur composite particles was enhanced compared with Z-Cur or ZG-Cur particles. Fourier transform infrared (FTIR) spectroscopy confirmed that the hydrogen bond within the particles was greatly enhanced after the addition of tannic acid (TA). The in vitro antioxidant activity of Cur in ZGT-Cur composite particles was higher in terms of 2,2'-azino-bis (ABTS) (93.64%) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) (50.41%) compared with Z-Cur or ZG-Cur particles. The bioaccessibility of Cur in ZGT-Cur composite particles was 8.97 times higher than that of free Cur. Therefore, the particles designed in this study will broaden the application of Cur in the food industry by improving its stability and bioaccessibility.

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.

pH-driven self-assembly of alcohol-free curcumin-loaded propylene glycol alginate nanoparticles

The purpose of this paper was to explore the application of propylene glycol alginate (PGA) alone in alcohol-free curcumin-loaded nanoparticles (PGA/Cur) prepared by a pH-driven method to solve the curcumin shortcomings of low water solubility, stability and bioavailability. One of the bright spots of PGA/Cur was its extremely high loading capacity. PGA/Cur formed a spherical structure mainly by hydrophobic interaction and hydrogen bonding, making curcumin amorphous. PGA/Cur exhibited stability at pH 4.0-8.0 due to its high surface charges. PGA/Cur still showed a unimodal size distribution even under 3000 mM ionic strength. Heating caused uneven size distribution, but the smaller size still presented its thermostability. PGA/Cur exhibited good physical stability and slowed down the curcumin degradation with t_1/2 of 37.47 days during storage. PGA/Cur could maintain structural integrity in gastric acid and released curcumin in the intestine, thus improving the bioaccessibility of curcumin. Additionally, PGA/Cur displayed the solubilization after lyophilization.

Study on the stability and oral bioavailability of curcumin loaded (-)-epigallocatechin-3-gallate/poly(N-vinylpyrrolidone) nanoparticles based on hydrogen bonding-driven self-assembly

The biological activity and absorption of curcumin (Cur) is limited in application due to its low water solubility, poorstabilityand rapid metabolism. In this work, Cur loaded (-)-epigallocatechin-3-gallate (EGCG)/poly(N-vinylpyrrolidone) (PVP) nanoparticles (CEP-NPs) was successfully fabricated via self-assembly driven by hydrogen bonding, providing with desirable Cur-loading efficiency, high stability, strong antioxidant capacity, and pH-triggered intestinal targeted release properties. Molecular dynamics simulations further indicated the Cur was coated with EGCG and PVP in CEP-NPs and high acid prolonged release property was attribute to low ionization degree of EGCG. Besides, the enhanced intestinal absorption of Cur was related to inhibition of Cur metabolism by EGCG, enhancement of cellular uptake and higher Caco-2 monolayer permeation. Pharmacokinetic study showed that the oral bioavailability presented nearly 12-fold increment. Therefore, this study provides a new horizon for improving the Cur utilization in food and pharmaceutical fields.

Fabrication and Characterization of Quercetagetin-Loaded Nanoparticles Based on Shellac and Quaternized Chitosan: Improvement of Encapsulation Efficiency and Acid and Storage Stabilities

Shellac can be used as an ideal delivery vehicle to deliver and protect the hydrophobic quercetagetin; the barriers such as low acid stability and encapsulation efficiency, however, heavily impede the application of shellac. The purpose of this work is to prepare quercetagetin-loaded shellac-quaternized chitosan nanoparticles (Que-Sh-QCS NPs) to overcome these challenges. Herein, quaternized chitosan, with 14% degree of substitution, was successfully synthesized via a quaternization modification. The concentration of quaternized chitosan over 0.05% can prevent the aggregation of shellac nanoparticles at the acid. The encapsulation efficiency of quercetagetin obviously increased from 37.92 to 65.48% with the concentration of QCS varying from 0 to 0.05%. Meanwhile, Que-Sh-QCS_0.05 NPs possessed good storage stability, antioxidant property, biocompatibility, and controlled release. Therefore, quaternized chitosan can improve the encapsulation efficiency and acid and storage stabilities of nutraceutical-loaded shellac nanoparticles, providing a new insight into the application of shellac in cosmetics, pharmaceuticals, and food.

Zein as a versatile biopolymer: different shapes for different biomedical applications

In recent years, the interest regarding the use of proteins as renewable resources has deeply intensified. The strongest impact of these biomaterials is clear in the field of smart medicines and biomedical engineering. Zein, a vegetal protein extracted from corn, is a suitable biomaterial for all the above-mentioned purposes due to its biodegradability and biocompatibility. The controlled drug delivery of small molecules, fabrication of bioactive membranes, and 3D assembly of scaffold for tissue regeneration are just some of the topics now being extensively investigated and reported in the literature. Herein, we review the recent literature on zein as a biopolymer and its applications in the biomedical world, focusing on the different shapes and sizes through which it can be manipulated.

Zein a versatile biomaterial in the biomedical field. Easy to chemically functionalize with good emulsification properties, can be employed in drug delivery, fabrication of bioactive membranes and 3D scaffolds for tissue regeneration.

Development, Characterization, Stability and Bioaccessibility Improvement of 7,8-Dihydroxyflavone Loaded Zein/Sophorolipid/Polysaccharide Ternary Nanoparticles: Comparison of Sodium Alginate and Sodium Carboxymethyl Cellulose

In this study, two polysaccharides [sodium alginate (ALG) and sodium carboxymethyl cellulose (CMC)] were selected to establish zein/sophorolipid/ALG (ALG/S/Z) and zein/sophorolipid/ALG (CMC/S/Z) nanoparticles to encapsulate 7,8-dihydroxyflavone (7,8-DHF), respectively. The results showed that polysaccharide types significantly affected performance of ternary nanoparticles, including CMC/S/Z possessed lower polydispersity index, particle size and turbidity, but higher zeta potential, encapsulation efficiency and loading capacity compared to ALG/S/Z. Compared to zein/sophorolipid nanoparticles (S/Z), both ALG/S/Z and CMC/S/Z had better stability against low pH (pH 3~4) and high ionic strengths (150~200 mM NaCl). Hydrophobic effects, electrostatic interactions and hydrogen bonding were confirmed in ternary nanoparticles fabrication via Fourier-transform infrared spectroscopy. Circular dichroism revealed that CMC and ALG had no evident impact on secondary structure of zein in S/Z, but changed surface morphology of S/Z as observed by scanning electron microscope. Encapsulated 7,8-DHF exhibited an amorphous state in ternary nanoparticles as detected by X-ray diffraction and differential scanning calorimetry. Furthermore, compared to S/Z, ALG/S/Z, and CMC/S/Z remarkably improved the storage stability and bioaccessibility of 7,8-DHF. CMC/S/Z possessed a greater storage stability for 7,8-DHF, however, ALG/S/Z exhibited a better in vitro bioaccessibility of 7,8-DHF. This research provides a theoretical reference for zein-based delivery system application.