Fabrication and characterization of zein-alginate oligosaccharide complex nanoparticles as delivery vehicles of curcumin

Interaction of zein/HP-β-CD nanoparticles with digestive enzymes: Enhancing curcumin bioavailability

The low bioavailability of polyphenolic compounds due to poor solubility and stability is a major challenge. Encapsulation of polyphenols in zein-based composite nanoparticles can improve the water dispersion, stability, targeted delivery, and controlled release of polyphenols in the gastrointestinal tract. In this study, we investigated the fluorescence properties, bioactivity, and microstructural characteristics of polyphenols during digestion, revealing that zein nanoparticles protect polyphenols from gastric degradation and promote their sustained release in the small intestine. The effects of different ionic species and salt ion concentrations on the digestive properties of polyphenol complex delivery systems have also been explored. In addition, the formation of "protein corona" structures during digestion may affect bioavailability. These findings highlight the potential of nanoparticle formulations to improve polyphenol stability and absorption. The results of this study may provide new insights and references for the study of polyphenol bioavailability enhancement.

Zein/fucoidan-coated phytol nanoliposome: preparation, characterization, physicochemical stability, in vitro release, and antioxidant activity

BACKGROUND

To improve phytol bioavailability, a novel method of magnetic stirring and high-pressure homogenization (HPH) combination was used to prepare zein/fucoidan-coated phytol nanoliposomes (P-NL-ZF). The characterization, the simulated in vitro digestion, and the antioxidant activity of these phytol nanoliposomes from the different processes have been studied.

RESULTS

Based on the results of dynamic light scattering (DLS) and gas chromatography-mass spectrometer (GC-MS) analysis, P-NL-ZF prepared through the combination of magnetic stirring and HPH exhibited superior encapsulation efficiency at 76.19% and demonstrated exceptional physicochemical stability under a series of conditions, including storage, pH, and ionic in comparison to single method. It was further confirmed that P-NL-ZF by magnetic stirring and HPH displayed a uniform distribution and regular shape through transmission electron microscopy (TEM). Fourier-transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) analysis showed that electrostatic interactions and hydrogen bonding were the primary driving forces for the formation of composite nanoliposomes. Additionally, an in vitro digestion study revealed that multilayer composite nanoliposomes displayed significant and favorable slow-release properties (58.21%) under gastrointestinal conditions compared with traditional nanoliposomes (82.36%) and free phytol (89.73%). The assessments of chemical and cell-based antioxidant activities demonstrated that the coating of zein/fucoidan on phytol nanoliposomes resulted in enhanced effectiveness in scavenging activity of ABTS free radical and hydroxyl radical and mitigating oxidative damage to HepG2 cells.

CONCLUSION

Based on our studies, the promising delivery carrier of zein/fucoidan-coated nanoliposomes is contributed to the encapsulation of hydrophobic natural products and enhancement of their biological activity. © 2024 Society of Chemical Industry.

Thermo-responsive composite nanoparticles based on hydroxybutyl chitosan oligosaccharide: Fabrication, stimulus release and cancer therapy

Designing thermo-responsive nanocarriers based on biopolymers is fascinating and challenging for cancer therapy. In this study, thermo-responsive composite nanoparticles (CNPs) were prepared using hydroxybutyl chitosan oligosaccharide (HBCOS) and sodium caseinate (SC) via electrostatic interactions and covalent crosslinking. The temperature-responsive behaviors of CNPs were induced by the breakage of hydrogen bonds and the shrinkage of chains in nanoparticles. The CNPs exhibited concentration-independent thermo-responsive behavior, non-adsorption aggregation, and non-hemolysis, suggesting excellent stability and thermo-sensitivity. The initial release rate and final amount of DOX released from CNPs at 42 °C were higher than that at 37 °C, showing a thermo-responsive release, which was also more prominent at lower pH. The release of DOX from CNPs followed first order kinetics based on Fickian diffusion. In vitro cytotoxicity assays confirmed the thermo-responsive antitumor activity of DOX-loaded CNPs as the HT-29 cell viability incubated with DOX-loaded CNPs at 42 °C was significantly lower than that at 37 °C. Cellular uptake experiments proved that DOX-loaded CNPs accumulated in the cytoplasm after being endocytosed and promoted DOX release by increasing environment temperature. This study generated stable thermo-sensitive CNPs based on biopolymers, which can be used as potential nanocarriers for the controlled release of anticancer drugs for cancer therapy.

Enhanced oral bioavailability of cannabidiol by flexible zein nanoparticles: in vitro and pharmacokinetic studies

Introduction

Cannabidiol (CBD) has a variety of pharmacological effects including antiepileptic, antispasmodic, anxiolytic and anti-inflammatory among other pharmacological effects. However, since CBD is a terpene-phenolic compound, its clinical application is limited by its poor water solubility, low stability, and low bioavailability.

Methods

In this study, we used several strategies to address the above problems. Hydrochloric acid was used to modify zein to improve the molecular flexibility. Flexible zein nanoparticles (FZP-CBD) loaded with CBD was prepared to improve the stability and bioavailability of CBD. The parameters were evaluated in terms of morphology, particle size (PS), polydispersity index (PDI), zeta potential (ZP), entrapment efficiency (EE%), loading capacity (LC%), and storage stability. Simulated gastrointestinal fluid release experiment and bioavailability assay were applied in the evaluation.

Results

The simulated gastrointestinal fluid experiment showed that the release rates of FZP-CBD and natural zein nanoparticles (NZP-CBD) loaded with CBD were 3.57% and 89.88%, respectively, after digestion with gastric fluid for 2 h, 92.12% and 92.56%, respectively, after intestinal fluid digestion for 2 h. Compared with NZP-CBD, the C max of FZP-CBD at 3 different doses of CBD was increased by 1.7, 1.3 and 1.5 times respectively, and AUC0-t was increased by 1.4, 1.1 and 1.7 times respectively, bioavailability (F) was increased by 135.9%, 114.9%, 169.6% respectively.

Discussion

The experimental results showed that FZP-CBD could protect most of the CBD from being released in the stomach, and then control its release in the intestines, promote the absorption of CBD in the small intestine, and increase the bioavailability of CBD. Therefore, FZP-CBD could improve the utilization value of CBD and provide a new idea for the application of CBD in medicine and pharmacy.

Preparation and characterization of tilapia protein isolate - Hyaluronic acid complexes using a pH-driven method for improving the stability of tilapia protein isolate emulsion

This study aimed to investigate the non-covalent complexation between hyaluronic acid (HA) and tilapia protein isolate (TPI) on the stability of oil-in-water (O/W) TPI emulsion. The results showed that HA binds to TPI through electrostatic, hydrophobic, and hydrogen bonding interactions, forming homogeneous hydrophilic TPI-HA complexes. The binding of HA promoted the structural folding of TPI and altered its secondary structure during pH neutralization. The TPI-HA complexes presented significantly improved EAI and ESI (P < 0.05) when the HA concentration was 0.8 % (w/v). Emulsion characterization showed that HA promoted the transfer of TPI to the O/W interface, forming an emulsion with excellent stability, which, combined with the high surface charge and strong spatial site resistance effect of HA, improved TPI emulsion stability. Therefore, non-covalent complexation with HA is an effective strategy to improve the stability of TPI emulsion.

Design and Characterization of a Novel Core-Shell Nano Delivery System Based on Zein and Carboxymethylated Short-Chain Amylose for Encapsulation of Curcumin

Curcumin is a naturally occurring hydrophobic polyphenolic compound with a rapid metabolism, poor absorption, and low stability, which severely limits its bioavailability. Here, we employed a starch-protein-based nanoparticle approach to improve the curcumin bioavailability. This study focused on synthesizing nanoparticles with a zein "core" and a carboxymethylated short-chain amylose (CSA) "shell" through anti-solvent precipitation for delivering curcumin. The zein@CSA core-shell nanoparticles were extensively characterized for physicochemical properties, structural integrity, ionic stability, in vitro digestibility, and antioxidant activity. Fourier-transform infrared (FTIR) spectroscopy indicates nanoparticle formation through hydrogen-bonding, hydrophobic, and electrostatic interactions between zein and CSA. Zein@CSA core-shell nanoparticles exhibited enhanced stability in NaCl solution. At a zein-to-CSA ratio of 1:1.25, only 15.7% curcumin was released after 90 min of gastric digestion, and 66% was released in the intestine after 240 min, demonstrating a notable sustained release effect. Furthermore, these nanoparticles increased the scavenging capacity of the 1,1-diphenyl-2-picrylhydrazyl (DPPH•) free radical compared to those composed solely of zein and were essentially nontoxic to Caco-2 cells. This research offers valuable insights into curcumin encapsulation and delivery using zein@CSA core-shell nanoparticles.

Preparation, structural characterization, and functional attributes of zein-lysozyme-κ-carrageenan ternary nanocomposites for curcumin encapsulation

The low water solubility and inadequate bioavailability of curcumin significantly hinder its broad biological applications in the realms of food and medicine. There is limited information currently available regarding the particle characteristics and functional capabilities of zein-lysozyme-based nanomaterials. Thereby, the primary goal of the current work is to effectively develop innovative zein-lysozyme-κ-carrageenan complex nanocomposites (ZLKC) as a reliable carrier for curcumin encapsulation. As a result, ZLKC nanoparticles showed a smooth spherical nanostructure with improved encapsulation efficiency. Fourier-transform infrared, fluorescence spectroscopy, dissociation assay, and circular dichroism analysis revealed that hydrophobic and electrostatic interactions and hydrogen bonding were pivotal in the construction and durability of these composites. X-ray diffraction examination affirmed the lack of crystallinity in curcumin encapsulated within nanoparticles. The incorporation of κ-carrageenan significantly improved the physicochemical stability of ZLKC nanoparticles in diverse environmental settings. Additionally, ZLKC nanocomposites demonstrated enhanced antioxidant and antimicrobial properties, as well as sustained release characteristics. Therefore, these findings demonstrate the potential application of ZLKC nanocomposites as delivery materials for encapsulating bioactive substances.

Conception of pH-sensitive calcium alginate/poly vinyl alcohol hydrogel beads for controlled oral curcumin delivery systems. Antibacterial and antioxidant properties

Curcumin, a bioactive compound derived from the rhizome of Curcuma longa, has gained widespread attention for its potential therapeutic properties, including anti-inflammatory, antioxidant and anticancer effects. However, its poor aqueous solubility, instability and limited bioavailability have hindered its clinical applications. New beads formulations based on sodium alginate biopolymer (SA) and poly vinyl alcohol (PVA) were successfully prepared and evaluated as a potential drug vehicle for extended release of curcumin (Cur). Pristine and curcumin loaded calcium alginate/poly vinyl alcohol beads (CA/PVA and CA/PVA/Cur) at different compositions of SA and PVA were prepared by an ionotropic gelation method of SA followed by two freeze-thawing (FT) cycles for further crosslinking of PVA. Characterization techniques, such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), UV-Visible spectroscopy, thermogravimetric analysis (TGA) and x-ray diffraction (XRD) were used to confirm the successful microencapsulation of curcumin within the CA/PVA microcapsules. Furthermore, the swelling of pristine beads, pH-sensitive properties and in vitro release studies of curcumin loaded beads were investigated at 37 °C in simulated gastric fluid (SGF), simulated intestinal fluid (SIF) and simulated colonic fluid (SCF). The effect of the polymer blend ratio, the encapsulation efficiency (EE %) of curcumin, the loading capacity (LC μg/mg), the sphericity factor (SF), the antioxidant activity of the elaborated beads and their antimicrobial properties against bacteria and fungi were just as much evaluated. The obtained results indicate that the swelling and the behavior of the developed beads were influenced by the pH of the test medium and the PVA content. The introduction of PVA into the SA matrix greatly enhanced the physicochemical properties, the encapsulation efficiency and the loading capacity of the elaborated microparticles. Results also suggested that the antioxidant activity of the loaded beads (CA/PVA/Cur) showed a higher DPPH radical scavenging activity while the bacterial and fungal strains proved sensitive to the different formulations used in the assay. Moreover, the important drug encapsulation efficiency and the sustainable drug release of these materials make them promising for the development of new drug carrier systems for colon targeting.

Fabrication and characterization of pectin-zein nanoparticles containing tanshinone using anti-solvent precipitation method

Tanshinone compounds are secondary metabolites which their application in food and pharmaceutical industry is limited due to the low solubility in water and sensitivity to heat. This study aimed to develop a novel biopolymer nanocarriers system based on pectin/zein for the encapsulation of tanshinone compounds using the anti-solvent precipitation method. The concentration of pectin and mass ratio of tanshinone/zein in the final formulation of nanoparticles were optimized. According to the results, a pectin concentration of 1 g/L and a tanshinone/zein ratio of 0.1:1 g/g were considered the optimal nanoparticle formulation. The resulting nanoparticles exhibited a spherical core-shell structure, with approximate values for size, zeta potential, TSI, and encapsulation efficiency of 132 ± 0.002 nm, -38.6 ± 0.019 mV, 0.600 ± 0.084, and 79.41 ± 0.62 %, respectively. The FTIR test confirmed the presence of hydrophobic, hydrogen, and electrostatic interactions among the constituents within the nanoparticles. Additionally, XRD and DSC tests verified the amorphous nature of the nanoparticles. Morphological examination conducted through TEM, and SEM revealed the characteristics of the resulting nanoparticles. Furthermore, this carrier system significantly enhanced the solubility of tanshinone compounds in water.

Antimicrobial and antioxidant activity of encapsulated tea polyphenols in chitosan/alginate-coated zein nanoparticles: a possible supplement against fish pathogens in aquaculture

Regulation of antibiotic use in aquaculture calls for the emergence of more sustainable alternative treatments. Tea polyphenols (GTE), particularly epigallocatechin gallate (EGCG), have various biological activities. However, tea polyphenols are susceptible to degradation. In this work, EGCG and GTE were encapsulated in zein nanoparticles (ZNP) stabilized with alginate (ALG) and chitosan (CS) to reduce the degradation effect. ALG-coated ZNP and ALG/CS-coated ZNP encapsulating EGCG or GTE were obtained with a hydrodynamic size of less than 300 nm, an absolute ζ-potential value >30 mV, and an encapsulation efficiency greater than 75%. The antioxidant capacity of the encapsulated substances, although lower than that of the free ones, maintained high levels. On the other hand, the evaluation of antimicrobial activity showed greater efficiency in terms of growth inhibition for ALG/CS-ZNP formulations, with average overall values of around 60%, reaching an inhibition of more than 90% for Photobacterium damselae. These results support encapsulation as a good strategy for tea polyphenols, as it allows maintaining significant levels of antioxidant activity and increasing the potential for antimicrobial activity, in addition to increasing protection against sources of degradation.

A Novel Strategy to Enhance the pH Stability of Zein Particles through Octenyl Succinic Anhydride-Modified Starch: The Role of Preparation pH

Ensuring the stability of zein nanoparticles at different pH levels is crucial for their application as nanocarriers. In this study, octenyl succinic anhydride-modified starch (OSA-modified starch) was employed to enhance the stability of zein nanoparticles against different pH levels by forming complex nanoparticles with OSA-modified starch. The effect of preparation pH on the stability of the zein/OSA-modified starch nanoparticles was investigated. Sedimentation occurred in zein nanoparticles as the pH reached the isoelectric point. However, the stability of zein nanoparticles at various pH levels significantly improved after adding OSA-modified starch to form zein/OSA-modified starch nanoparticles regardless of whether they were prepared under acidic or alkaline pH conditions. Notably, the stability of zein/OSA-modified starch nanoparticles prepared at an acidic pH was higher than that of those prepared at an alkaline pH, thereby highlighting the critical role of the preparation pH for zein/OSA-modified starch in maintaining the stability of zein. The stable zein/OSA-modified starch nanoparticles developed in this study exhibit significant potential for use in delivery systems across various pH environments.

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.

A non-thermal modification method to promote the interaction of zein-alginate oligosaccharides composites for better encapsulation and stability-Cold plasma

This current research explored the application of cold plasma (CP) treatment to modify zein-alginate oligosaccharide (zein-AOS) composites in an ethanol-water solution. Anti-solvent method was used to prepare zein-AOS nanoparticles (NPs), and the objective was to investigate the mechanism by which CP promotes interaction between protein and saccharides. Characterization results indicated that CP treatment improved hydrogen bonding and electrostatic interaction between zein and AOS. The CP zein-AOS NPs underwent dispersion and rearrangement, resulting in smaller aggregates with better dispersibility. Among the various induction conditions tested, the zein-AOS85 NPs (induced at 85 W for 2 min) exhibited superior performance as delivery wall materials, with smaller particle size (234.67 nm), larger specific surface area (9.443 m2/g), and higher surface charge (-35.43 mV). In addition, zein-AOS85 showed high stability when used as delivery wall material, providing more binding sites and self-assembly dynamics for nutrients. Curcumin was used as the nutrient model in this study, and CP was found to enhance hydrogen bonding, electrostatic interaction, and hydrophobic interaction between zein, AOS, and nutrients, resulting in increased encapsulation efficiency (EE) from 63.80 % to 85.17 %. The delivery system also exhibited good pH, ionic strength, storage, and dispersion stability.

Curcumin loaded Zein-alginate nanogels with "core-shell" structure: formation, characterization and simulated digestion

Zein nanoparticles tend to aggregate in water and are readily digested by enzymes in the gastrointestinal tract. In current study, the Zein-alginate nanogels loaded with curcumin (Cur@ZA) were fabricated with the "core-shell" structure. The Zein "core" was prepared via antisolvent precipitation method, and the alginate gel "shell" was formed by calcium-induced gelation method. The physicochemical properties, microstructure, encapsulation efficiency, stability and simulated digestion characteristics of nanogels were investigated. The results showed that Cur@ZA formed uniform gel spheres with small particle size (415.10 nm), while possessing a dense gel shell on the surface. The Zein "core" and alginate gel "shell" of Cur@ZA are tightly bound to each other by electrostatic adsorption, hydrophobic interaction and hydrogen bonding. Curcumin was able to be loaded in the Cur@ZA nanogels with a higher encapsulation rate (>92 %). Compared with the system which was not induced by calcium ion, the addition of calcium ions improved the photostability and thermal stability of curcumin, and facilitated slow and sustained release of curcumin in the simulated digestion. Therefore, this novel nanogel delivery system has the ideal physicochemical properties, stability and control-release ability, which has the potential to be used in the food industry.

Modulating the glycemic response of starch-based foods using organic nanomaterials: strategies and opportunities

Traditionally, diverse natural bioactive compounds (polyphenols, proteins, fatty acids, dietary fibers) are used as inhibitors of starch digestive enzymes for lowering glycemic index (GI) and preventing type 2 diabetes mellitus (T2DM). In recent years, organic nanomaterials (ONMs) have drawn a great attention because of their ability to overcome the stability and solubility issues of bioactive. This review aimed to elucidate the implications of ONMs in lowering GI and as encapsulating agents of enzymes inhibitors. The major ONMs are presented. The mechanisms underlying the inhibition of enzymes, the stability within the gastrointestinal tract (GIT) and safety of ONMs are also provided. As a result of encapsulation of bioactive in ONMs, a more pronounced inhibition of enzymes was observed compared to un-encapsulated bioactive. More importantly, the lower the size of ONMs, the higher their inhibitory effects due to facile binding with enzymes. Additionally, in vivo studies exhibited the potentiality of ONMs for protection and sustained release of insulin for GI management. Overall, regulating the GI using ONMs could be a safe, robust and viable alternative compared to synthetic drugs (acarbose and voglibose) and un-encapsulated bioactive. Future researches should prioritize ONMs in real food products and evaluate their safety on a case-by-case basis.

Physicochemical stability, antioxidant activity, and antimicrobial activity of quercetin-loaded zein nanoparticles coated with dextrin-modified anionic polysaccharides

Core-shell biopolymer nanoparticles are assembled from a hydrophobic protein (zein) core and a hydrophilic polysaccharide (carboxymethyl dextrin) shell. The nanoparticles were shown to have good stability and the ability to protect quercetin from chemical degradation under long-term storage, pasteurization, and UV irradiation. Spectroscopy analysis shows that electrostatic, hydrogen bonding, and hydrophobic interactions are the main driving forces for the formation of composite nanoparticles. Quercetin coated with nanoparticles significantly enhanced its antioxidant and antibacterial activities and showed good stability and slow release in vitro during simulated gastrointestinal digestion. Furthermore, the encapsulation efficiency of carboxymethyl dextrin-coated zein nanoparticles (81.2%) for quercetin was significantly improved compared with that of zein nanoparticles alone (58.4%). These results indicate that carboxymethyl dextrin-coated zein nanoparticles can significantly improve the bioavailability of hydrophobic nutrient molecules such as quercetin and provide a valuable reference for their application in the field of biological delivery of energy drinks and food.

Recent Advances in Zein-Based Nanocarriers for Precise Cancer Therapy

Cancer has emerged as a leading cause of death worldwide. However, the pursuit of precise cancer therapy and high-efficiency delivery of antitumor drugs remains an enormous obstacle. The major challenge is the lack of a smart drug delivery system with the advantages of biodegradability, biocompatibility, stability, targeting and response release. Zein, a plant-based protein, possesses a unique self-assembly ability to encapsulate anticancer drugs directly or indirectly. Using zein as a nanotherapeutic pharmaceutic preparation can protect anticancer drugs from harsh environments, such as sunlight, stomach acid and pepsin. Moreover, the surface functionalization of zein is easily realized, which can endow it with targeting and stimulus-responsive release capacity. Hence, zein is an ideal nanocarrier for the precise delivery of anticancer drugs. Combined with our previous research experiences, we attempt to review the current state of the preparation of zein-based nanocarriers for anticancer drug delivery. The challenges, solutions and development trends of zein-based nanocarriers for precise cancer therapy are discussed. This review will provide a guideline for precise cancer therapy in the future.

Calcitriol-Loaded Multifunctional Nanospheres with Superlubricity for Advanced Osteoarthritis Treatment

Osteoarthritis (OA) is characterized by the lubrication dysfunction of a cartilage sliding interface caused by chronic joint inflammation, and effective nonsurgical therapy for advanced OA remains lacking. Addressing chronic joint inflammation, lubrication dysfunction, and cartilage-tissue degradation simultaneously may hopefully tackle this challenge. Herein, we developed superlubricative zein@alginate/strontium@calcitriol (ZASC) nanospheres to treat advanced OA. ZASC was confirmed to significantly improve joint lubrication through traditional tribological tests and our proposed tribological experiment to mimic the intra-articular condition based on the human medial tibiofemoral joint tissues. This finding was attributed to the hydration lubrication formed around the alginate-strontium spheres that enabled ball-bearing lubrication and the filling of cartilage defects. Moreover, ZASCs that released calcitriol in a sustained manner showed proliferative, anti-inflammatory, and anti-apoptosis effects in vitro. Further experiments demonstrated that ZASC exerted chondroprotective effects by inhibiting the breakdown of the extracellular matrix in patient-derived OA cartilage explants. In vivo results demonstrated that ZASC can effectively maintain a normal gait to improve joint function, inhibit abnormal bone remodeling and cartilage degradation in early OA and can effectively reverse the advanced OA progression. Therefore, ZASC is a potentially nonsurgical therapeutic strategy for advanced OA treatments.

Cold plasma treatment with alginate oligosaccharide improves the digestive stability and bioavailability of nutrient-delivered particles: An in vitro INFOGEST gastrointestinal study

To improve the stability and bioavailability of the delivered hydrophobic nutrients, the zein-based delivery system was modified by alginate oligosaccharide (AOS), cold plasma (CP) treatments, and synergistically. The digestive behavior of each was investigated in an INFOGEST static in vitro digestion model. The results showed that AOS and CP treatments and their synergistic effects improved the dispersion and stability of the delivery system, leading to a more concentrated particle size distribution and higher particle surface charge. Both CP treatments and AOS increased the release rate of Curcumin (Cur) at small intestine (11.8 % to 20.5 % and 11.8 % to 24.64 %, respectively), and the synergistic effect was higher (11.8 % to 43.84 %). The wall material modified showed a higher encapsulation efficiency of Cur (52.83 % to 85.17 %). Cur release rate measurements showed that the wall material modified could have a positive effect on the slow release of Cur. SDS-page electrophoresis revealed that the slow release was due to the enhanced resistance of wall material to digestive fluids. Thus, treatment with AOS and CP treatments, and the synergism are suitable for modifying zein-based delivery systems for the encapsulation, stabilization, and slow release of hydrophobic nutrients during digestion in the field of functional foods.

Biopolymer- and Lipid-Based Carriers for the Delivery of Plant-Based Ingredients

Natural ingredients are gaining increasing attention from manufacturers following consumers’ concerns about the excessive use of synthetic ingredients. However, the use of natural extracts or molecules to achieve desirable qualities throughout the shelf life of foodstuff and, upon consumption, in the relevant biological environment is severely limited by their poor performance, especially with respect to solubility, stability against environmental conditions during product manufacturing, storage, and bioavailability upon consumption. Nanoencapsulation can be seen as an attractive approach with which to overcome these challenges. Among the different nanoencapsulation systems, lipids and biopolymer-based nanocarriers have emerged as the most effective ones because of their intrinsic low toxicity following their formulation with biocompatible and biodegradable materials. The present review aims to provide a survey of the recent advances in nanoscale carriers, formulated with biopolymers or lipids, for the encapsulation of natural compounds and plant extracts.

Chitosan-based carbon nitride-polydopamine‑silver composite dressing with antibacterial properties for wound healing

Infection represents a major clinical barrier that delays wound healing, while the overuse of antibiotics can lead to bacterial resistance. Hence, it is of particular important to develop a new type of dressing to combat bacterial resistance. Herein, a carbon nitride-polydopamine‑silver complex (C₃N₄-PDA-Ag) was prepared using the photocatalyst C₃N₄ and silver nanoparticles (Ag NPs) to achieve a synergistic antimicrobial effect. The solution casting method was then employed to further modify the C₃N₄-PDA-Ag complex by compounding it with chitosan (CS), thereby forming a C₃N₄-PDA-Ag@CS film. The results revealed that the C₃N₄-PDA-Ag@CS film exhibits superior antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa compared to the CS group. The hemolysis, cytotoxicity, and in vivo implantation experiments indicated that the composite film possesses excellent in vitro and in vivo biocompatibility. In addition, the composite dressing promoted wound healing in infected mice by facilitating collagen deposition and accelerating epidermal regeneration. Collectively, the findings of this study clearly demonstrate that the C₃N₄-PDA-Ag@CS composite dressing has excellent antibacterial properties, biocompatibility, and enhances wound healing, thus providing a strategy for the application of photocatalytic materials for the treatment of infected wounds.

Properties of curcumin-loaded zein-tea saponin nanoparticles prepared by antisolvent co-precipitation and precipitation

The properties of nutraceutical-loaded biopolymer nanoparticles fabricated by antisolvent co-precipitation (ASCP) and precipitation (ASP) were compared. Curcumin-loaded zein-tea saponin nanoparticles were fabricated using both methods and then their structural and physicochemical properties were characterized. The diameter of the nanoparticles prepared by ASCP were smaller (120-130 nm) than those prepared by ASP (140-160 nm). The encapsulation efficiency of the ASCP-nanoparticles (80.0%) was higher than the ASP-ones (71.0%) at a zein-to-curcumin mass ratio of 3:1, which was also higher than previous studies. The storage and light stability of curcumin was higher in zein-saponin nanoparticles than in zein nanoparticles. All nanoparticles had good water dispersibility after freeze-drying and rehydration. This study shows that nanoparticles produced by antisolvent co-precipitation have superior properties to those produced by antisolvent precipitation. The co-precipitation method leads to a higher encapsulation efficiency, smaller particle size, and greater storage stability, which may be advantageous for some applications.

Encapsulation and sustained release of curcumin by hawthorn pectin and Tenebrio Molitor protein composite hydrogel

In this study, the effects of pH value, mixing ratio and the Ca²⁺ concentration on the complex gelation of hawthorn pectin (HP) and Tenebrio Molitor protein (TMP) were investigated. The turbidity results showed that the composite gel had the maximum polymer concentration when the mixing ratio was 2:1 and the pH value was 3.35. The rheological measurement results showed that TMP/HP (15 mmol/L) hydrogel (THIH) had the highest storage modulus and loss modulus, indicating that the properties of the hydrogel at this Ca²⁺ concentration had been significantly improved. The results of scanning electron microscope and pore size also proved that the network structure prepared under this condition was compact and uniform, the pore size was small, which was beneficial to the entrapment of active components. Subsequently, in order to explore the storage stability and antioxidant activity of THIH-loaded curcumin in simulated gastrointestinal environment, in vitro simulated digestion experiment was carried out and satisfactory results were obtained. To sum up, THIH was a promising delivery system with broad application prospects, which was expected to provide a novel idea for the entrapment and delivery of active components.

Preparation and Characterization of Rutin–Loaded Zein–Carboxymethyl Starch Nanoparticles

In this work, rutin (RT)–loaded zein–carboxymethyl starch (CMS) nanoparticles were successfully prepared by the antisolvent precipitation method. The effect of CMS on composite nanoparticles at different concentrations was studied. When the ratio of zein–RT–CMS was 10:1:30, the encapsulation efficiency (EE) was the highest, reaching 73.5%. At this ratio, the size of the composite nanoparticles was 196.47 nm, and the PDI was 0.13, showing excellent dispersibility. The results of fluorescence spectroscopy, FTIR, XRD, and CD showed that electrostatic interaction, hydrogen bonding, and hydrophobic interaction were the main driving forces for the formation of nanoparticles. It can be seen from the FE–SEM images that the zein–RT–CMS nanoparticles were spherical. With the increase in the CMS concentration, the particles gradually embedded in the cross–linked network of CMS (10:1:50). After RT was loaded on zein–CMS nanoparticles, the thermal stability and pH stability of RT were improved. The results showed that zein–CMS was an excellent encapsulation material for bioactive substances.

Preparation of protamine-hyaluronic acid coated core-shell nanoparticles for enhanced solubility, permeability, and oral bioavailability of decoquinate

Decoquinate (DQ) has low oral bioavailability owing to its poor water solubility. In this study, a DQ solid dispersion (DQ-SD) was fabricated using mechanochemical technology to encapsulate DQ and improve its oral bioavailability. DQ-SD is easily generated via self-assembly in the aqueous phase to form micelles consisting of disodium glycyrrhizinate (Na₂GA) nanoparticles with a protamine (PRM) and anionic hyaluronic acid (HA) layers. The spherical DQ nanoparticles with an average diameter of 114.95 nm were obtained in an aqueous phase with a critical micelle concentration of 0.157 mg/mL, zeta potential of -38.38 mV, polydispersity index of 0.200, and drug loading of 5.66 %. The dissolution rate and cumulative release of DQ-SD were higher than those of pure DQ. Furthermore, the bioavailability of DQ-SD was approximately 6.3 times higher than that of pure DQ. Pharmacokinetic and biodistribution studies indicated that DQ-SD possessed a significantly higher concentration in the blood and preferential liver tissue accumulation, than that of pure DQ. The developed DQ-SD exhibited considerable potential for developing old DQ for a new application as a hematogenous parasite drug and provides a reference for developing more efficient delivery systems for hydrophobic bioactive agents.

Efficient Delivery of Curcumin by Alginate Oligosaccharide Coated Aminated Mesoporous Silica Nanoparticles and In Vitro Anticancer Activity against Colon Cancer Cells

We designed and synthesized aminated mesoporous silica (MSN-NH2), and functionally grafted alginate oligosaccharides (AOS) on its surface to get MSN-NH2-AOS nanoparticles as a delivery vehicle for the fat-soluble model drug curcumin (Cur). Dynamic light scattering, thermogravimetric analysis, and X-ray photoelectron spectroscopy were used to characterize the structure and performance of MSN-NH2-AOS. The nano-MSN-NH2-AOS preparation process was optimized, and the drug loading and encapsulation efficiencies of nano-MSN-NH2-AOS were investigated. The encapsulation efficiency of the MSN-NH2-Cur-AOS nanoparticles was up to 91.24 ± 1.23%. The pH-sensitive AOS coating made the total release rate of Cur only 28.9 ± 1.6% under neutral conditions and 67.5 ± 1% under acidic conditions. According to the results of in vitro anti-tumor studies conducted by MTT and cellular uptake assays, the MSN-NH2-Cur-AOS nanoparticles were more easily absorbed by colon cancer cells than free Cur, achieving a high tumor cell targeting efficiency. Moreover, when the concentration of Cur reached 50 μg/mL, MSN-NH2-Cur-AOS nanoparticles showed strong cytotoxicity against tumor cells, indicating that MSN-NH2-AOS might be a promising tool as a novel fat-soluble anticancer drug carrier.

Delivery of curcumin by fucoidan-coated mesoporous silica nanoparticles: Fabrication, characterization, and in vitro release performance

Mesoporous silica nanoparticles (MSN) are effective drug delivery carriers because of their adjustable large pore size and high porosity. In this study, complex nanoparticles containing disulfide bonds (SS) were designed and prepared as curcumin (Cur) carriers by using fucoidan (FUC) and MSN as the polymer matrix. The product was characterized using scanning electron microscopy, transmission electron microscopy, dynamic light scattering, Fourier-transform infrared spectroscopy, and an N₂ adsorption and desorption test. When the mass ratio of MSN to FUC was 2:1, the nanospheres particle size was the smallest (295.6 ± 0.98 nm, -35.2 ± 0.8 mV). Furthermore, the curcumin encapsulation rate by MSN-Cur-SS-FUC was over 90%, and the cumulative release rate in 24 h was over 80% due to the combined effect of weak acidity and high glutathione concentration in the tumor site microenvironment. When the Cur concentration was 50 μg/mL, the cell viability of free Cur was 63.8%, the cell viability of MSN-Cur-SS-FUC was 14.5%, and the cell viability of MSN-SS-FUC at the same concentration remained above 74.6%. MSN-SS-FUC composite nanoparticles showed a good delivery of Cur, a lipid-soluble active compound, and provides a new delivery route for other lipid-soluble and poorly bioavailable active compounds.

Fabrication and characterization of octenyl succinic anhydride modified pullulan micelles for encapsulating curcumin

BACKGROUND

Curcumin has become increasingly popular in functional foods and beverages field as a result of its high biological activity. Nevertheless, the application of curcumin is usually limited by its poor water solubility, low absorption, rapid metabolism and instability. Accordingly, the development of an appropriate wall material is crucial for its effective use. In the present study, curcumin-octenyl succinic anhydride modified pullulan (Cur-OSAP) micelles were successfully prepared by an anti-solvent co-precipitation method.

RESULTS

Octenyl succinic anhydride modified pullulan (OSAP) micelles exhibited the highest encapsulation efficiency (57.31%) and loading capacity (5.73%) of curcumin when the mass ratio of OSAP to curcumin was 10:1 and the degree of substitution of OSAP was 0.0469, at which point Cur-OSAP micelles formed via hydrogen binding and hydrophobic interactions, as confirmed by Fourier transform infrared and fluorescence techniques. The transmission electron microscopy results showed that the Cur-OSAP micelles were roughly spherical in shape with diameters in the approximate range 30-60 nm.

CONCLUSION

The encapsulation of OSAP greatly improved photostability and sustained release properties of curcumin in Cur-OSAP micelles. These findings suggest that OSAP can be used as a carrier to encapsulate and protect hydrophobic food ingredients. © 2021 Society of Chemical Industry.

Rational Fabrication of Folate-Conjugated Zein/Soy Lecithin/Carboxymethyl Chitosan Core-Shell Nanoparticles for Delivery of Docetaxel

The objective of this work is to design and fabricate a natural zein-based nanocomposite with core-shell structure for the delivery of anticancer drugs. As for the design, folate-conjugated zein (Fa-zein) was synthesized as the inner hydrophobic core; soy lecithin (SL) and carboxymethyl chitosan (CMC) were selected as coating components to form an outer shell. As for fabrication, a novel and appropriate atomizing/antisolvent precipitation process was established. The results indicated that Fa-zein/SL/CMC core-shell nanoparticles (FZLC NPs) were successfully produced at a suitable mass ratio of Fa-zein/SL/CMC (100:30:10) and the freeze-dried FZLC powder showed a perfect redispersibility and stability in water. After that, docetaxel (DTX) as a model drug was encapsulated into FZLC NPs at different mass ratios of DTX to FZLC (MR). When MR = 1:15, DTX/FZLC NPs were obtained with high encapsulation efficiency (79.22 ± 0.37%), small particle size (206.9 ± 48.73 nm), and high zeta potential (-41.8 ± 3.97 mV). DTX was dispersed in the inner core of the FZLC matrix in an amorphous state. The results proved that DTX/FZLC NPs could increase the DTX dissolution, sustain the DTX release, and enhance the DTX cytotoxicity significantly. The present study provides insight into the formation of zein-based complex nanocarriers for the delivery of anticancer drugs.

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.

A review of factors affecting the stability of zein-based nanoparticles loaded with bioactive compounds: from construction to application

Zein-based nanoparticles loaded with bioactive compounds have positive prospects in the food industry, but an important limiting factor for development is colloidal instability. Currently, extensive researches are focused on solving the instability of zein nanoparticles, but since the beginning of the studies, there has not been a summary of the factors affecting the stability of zein-based nanoparticles. In the present work, the factors were reviewed comprehensively from the perspective of carrier construction and application evaluation. The former mainly includes type, quantity, and characteristics of biopolymer, the mass ratio of biopolymer/bioactive compound to zein, blending sequence of biopolymer, and location of encapsulated bioactive compounds. The latter mainly includes pH, heating, ionic strength, storage, freeze-drying, and gastrointestinal digestion. The former is the prerequisite for the success of the latter. The challenge is that stability research is limited to the laboratory level, and it is difficult to ensure that the stability results are suitable for commercial food matrices due to their complexity. At the laboratory level, the future trends are the influence of external energy and the cross-complexity and uniformity of stability research. The review is expected to provide systematic understanding and guidance for the development of zein-based nanoparticles stability.

Fabrication and characterization of core-shell gliadin/tremella polysaccharide nanoparticles for curcumin delivery: Encapsulation efficiency, physicochemical stability and bioaccessibility

The objectives of the present study were to synthesize gliadin/tremella polysaccharide nanoparticles (Gli/TP NPs) as well as curcumin-loaded gliadin/tremella polysaccharide nanoparticles (Cur-Gli/TP NPs) and evaluate the encapsulation efficiency (EE), physicochemical stability and bioaccessibility of Cur-Gli/TP NPs. The physicochemical properties of the nanoparticles depended on the mass ratio of Gli to TP and pH values. The characterization of the Gli/TP NPs indicated that the prepared nanoparticles were the most stable when the Gli/TP mass ratio was 1:1 and pH was at 4.0-7.0. Afterward, prepared Cur-Gli/TP NPs at different pH values were studied. Compared with the EE of Cur (58.2%) in Cur-Gli NPs at pH 5.0, the EE of Cur (90.6%) in Cur-Gli/TP NPs at pH 5.0 was increased by 32.4%. Besides, the Cur-Gli/TP NPs possessed excellent physical stability, photostability, thermal stability and re-dispersibility than Cur-Gli NPs. Furthermore, the bioaccessibility of Cur reached 83.5% after encapsulation of Cur into Gli/TP NPs after in vitro digestion, indicating that Cur-Gli/TP NPs could improve curcumin bioaccessibility significantly. In summary, this study demonstrates that the new food-grade Gli/TP NPs possess high encapsulation efficiency, excellent stability and prominent nutraceutical bioaccessibility. Meanwhile, it contributes to expanding the application of TP in food-grade delivery systems.

Establishment and Characterization of Stable Zein/Glycosylated Lactoferrin Nanoparticles to Enhance the Storage Stability and in vitro Bioaccessibility of 7,8-Dihydroxyflavone

In this work, the lactoferrin (LF) was glycosylated by dextran (molecular weight 10, 40, and 70 kDa, LF 10K, LF 40K, and LF 70K) via Maillard reaction as a stabilizer to establish zein/glycosylated LF nanoparticles and encapsulate 7,8-dihydroxyflavone (7,8-DHF). Three zein/glycosylated LF nanoparticles (79.27–87.24 nm) with low turbidity (<0.220) and polydispersity index (PDI) (<0.230) were successfully established by hydrophobic interactions and hydrogen bonding. Compared with zein/LF nanoparticles, zein/glycosylated LF nanoparticles further increased stability to ionic strength (0–500 mM NaCl) at low pH conditions. Zein/glycosylated LF nanoparticles had nanoscale spherical shape and glycosylated LF changed surface morphology of zein nanoparticles. Besides, encapsulated 7,8-DHF exhibited an amorphous state inside zein/glycosylated LF nanoparticles. Most importantly, zein/glycosylated LF nanoparticles had good water redispersibility, high encapsulation efficiency (above 98.50%), favorable storage stability, and bioaccessibility for 7,8-DHF, particularly LF 40K. Collectively, the above research provides a theoretical reference for the application of zein-based delivery systems.

Cloning and Characterization of a Novel Alginate Lyase from Paenibacillus sp. LJ-23

As a low molecular weight alginate, alginate oligosaccharides (AOS) exhibit improved water solubility, better bioavailability, and comprehensive health benefits. In addition, their biocompatibility, biodegradability, non-toxicity, non-immunogenicity, and gelling capability make them an excellent biomaterial with a dual curative effect when applied in a drug delivery system. In this paper, a novel alginate lyase, Algpt, was cloned and characterized from a marine bacterium, Paenibacillus sp. LJ-23. The purified enzyme was composed of 387 amino acid residues, and had a molecular weight of 42.8 kDa. The optimal pH of Algpt was 7.0 and the optimal temperature was 45 °C. The analysis of the conserved domain and the prediction of the three-dimensional structure indicated that Algpt was a novel alginate lyase. The dominant degradation products of Algpt on alginate were AOS dimer to octamer, depending on the incubation time, which demonstrated that Algpt degraded alginate in an endolytic manner. In addition, Algpt was a salt-independent and thermo-tolerant alginate lyase. Its high stability and wide adaptability endow Algpt with great application potential for the efficient preparation of AOS with different sizes and AOS-based products.

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.

Alginate-based delivery systems for food bioactive ingredients: An overview of recent advances and future trends

Due to its advantagessuch as ionic crosslinking, pH responsiveness, excellent biocompatibility, biodegradability and low price, alginate has become one of the most important natural polysaccharides extensively used in constructing desired delivery systems for food bioactive ingredients. In this review, the fundamental knowledge of alginate as a building block for construction of nutraceutical delivery systems is introduced. Then, various types of alginate-based nutraceutical delivery systems are classified and summarized. Furthermore, the future trends of alginate-based delivery systems are highlighted. Currently, alginate-based delivery systems include hydrogel, emulsion, emulsion-filled alginate hydrogel, nanoparticle, microparticle, core-shell particle, liposome, edible film, and aerogel. Although alginate has been widely used in the fabrication of food bioactive ingredient delivery systems, further efforts and improvements are still needed. For this purpose, the future perspectives of alginate-based delivery systems are discussed. The feasible research trends of alginate-based delivery systems include the development of novel large-scale commercial preparation technology, multifunctional delivery system based on alginate, alginate oligosaccharide-based delivery system and alginate-based oleogel. Overall, the objective of this review is to provide useful guidance for rational design and application of alginate-based nutraceutical delivery systems in the future.