Improved stabilization of coix seed oil in a nanocage-coating framework based on gliadin-carboxymethyl chitosan-Ca2

Improving physical stability of microalgae protein-based emulsions under acidic and neutral conditions via carboxymethyl chitosan complexation

The emulsification stability of microalgae protein (MP) is limited to strongly alkaline conditions, restricting its applications in food processing. This study aims to investigate the capability of carboxymethyl chitosan (CMCS) to improve MP's emulsification stability over a wider pH range. Results indicated soluble MP-CMCS complexes formed at pH 2, 4, and 7, while aggregation of the complexes occurred at pH 8. The complexes stabilized emulsions exhibited smaller droplet sizes and higher absolute zeta potential at pH 2, 4, and 7 compared to pH 8. After 2 weeks of storage, emulsions remained stable at pH 2, 4, and 7, with significant delamination at pH 8. Laser confocal microscopy confirmed uniform droplet distribution at pH 2 and 7, with slight fusion at pH 4. The complexes stabilized emulsions exhibited higher viscosity and shear stress than MP stabilized emulsions at pH 2, 4, and 7. The stronger viscoelastic properties and higher storage moduli (G') values of MP-CMCS complexes under acidic and neutral conditions indicated stronger intermolecular interactions compared to alkaline conditions. The increase in G' and loss moduli (G") values for emulsions at pH 8 under stress highlighted the significant impact on network structure strength and viscosity in these emulsions. This study elucidated the binding interactions between MP and CMCS under various pH conditions, and demonstrated a feasible approach to improving MP's emulsification stability over a wider pH range.

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.

A Review on the Driving Forces in the Formation of Bioactive Molecules-Loaded Prolamin-Based Particles

Prolamin-based particles loaded with bioactive molecules have attracted widespread attention from scientists due to their novel properties in chemistry, physics, and biology. In the self-assembly process of biopolymer-based nanocapsules, noncovalent interactions are the main driving forces for reducing bulk materials to the nanoscale and controlling the release of bioactive molecules. This article reviews the types of interaction forces, binding strength, binding active sites, molecular orientation, and binding affinity that affect the release profile of bioactive molecules during the preparation of protein stabilizer particles. Different preparation formulations, the use of different biopolymers, the inherent nature of the loaded bioactive molecules, and external factors (including pH, biopolymer concentration, temperature, salt, ultrasonication, and atmospheric cold plasma treatment) lead to different types and strengths of intra- and intermolecular interactions. Strategies, such as pH, ultrasonication, and atmospheric cold plasma, to change the protein conformation are key to improving the binding strength between proteins and bioactive substances or stabilizers. This review provides some guidance for scientists and technicians dedicated to improving loading efficiency, delaying release, enhancing colloidal stability, and exploring the binding behavior among proteins, stabilizers, and bioactive molecules.

Development and characterization of emulsion gels prepared via gliadin-based colloidal particles and gellan gum with tunable rheological properties for 3D printed dysphagia diet

Dysphagia, a condition characterized by difficulty swallowing, has emerged as a threat to health. Herein, we investigated the feasibility of preparing a novel 3D-printed dysphagia diet using emulsions and gellan gum. A gel network was facilitated by the inclusion of gellan gum, which also helped to reduce the size of the oil droplets. Emulsion gels (with 0.3 %-0.5 % gellan gum) were stable at 25 °C for 30 days and tolerated a high ionic concentration of 800 mmol L-1. Emulsion gels remained stable after heat treatment and centrifugation. The excellent stability of the emulsion gels was related to the three-dimensional network developed by the gellan gum. The rheological results validated the solid-state behavior, shear thinning behavior and structural recovery of emulsion gels. Emulsion gels with 0.3 %-0.5 % gellan gum were suitable for 3D printing since they had high printing accuracy, self-support, and smooth surface texture. International Diet Standardization Initiative (IDDIS) tests have shown that emulsion gels can be classified as a level 3-5 dysphagia diet. In addition, the bioaccessibility of astaxanthin increased 1.7 times after being encapsulated by emulsion gels. Overall, these results demonstrate the potential of emulsion gels in the development of novel 3D-printed diets for dysphagia and bioactive protection.

Fabrication of carboxymethyl chitosan films for cheese packaging containing gliadin-carboxymethyl chitosan nanoparticles co-encapsulating natamycin and theaflavins

In this study, gliadin-carboxymethyl chitosan composite nanoparticles (GC NPs) co-encapsulated natamycin (Nata) and theaflavins (TFs) were constructed and added as an antioxidant, antifungal, and structural enhancer to carboxymethyl chitosan (CMCS) films. The stabilized GC NPs with a particle size of 160.7 ± 2.8 nm, a zeta potential of -29.0 ± 0.9 mV, and a protein content in the supernatant of 96 ± 1 % could be fabricated. Tests of pH and salt ions showed that the stability of NPs dispersion was based on electrostatic repulsion. Co-encapsulation of TFs enhanced the photostability of Nata and the antioxidant activity of the NPs dispersion. The interactions between gliadin with Nata and TFs were studied by molecular simulations. As a functional additive, the addition of Nata/TFs-GC NPs could improve the optical properties, mechanical properties, water-blocking capability, and antifungal and antioxidant activities of the CMCS films. The in-vivo test showed that the functional film could be used to inhibit the growth of Aspergillus niger on cheese.

Improving the emulsification performance of adlay seed starch by esterification combined with ultrasonication and enzymatic treatment

In this study, superior modified starch was prepared using ultrasonic and enzymatic treatments to confirm the potential of using adlay seed starch (ASS) in Pickering emulsions. Octenyl succinic anhydride (OSA)-modified starches, such as OSA-UASS, OSA-EASS, and OSA-UEASS, were prepared using ultrasonic, enzymatic, and combined ultrasonic and enzymatic treatments, respectively. The effects of these treatments on the structure and properties of ASS were evaluated to elucidate their influence on starch modification. Ultrasonic and enzymatic treatments improved the esterification efficiency of ASS by changing its external and internal morphological characteristics and the crystalline structure to provide more binding sites for esterification. The degree of substitution (DS) of ASS modified by these pretreatments was 22.3-51.1 % higher than that of the OSA-modified starch without pretreatment (OSA-ASS). Fourier transform infrared and X-ray photoelectron spectroscopy results confirmed the esterification. Small particle size and near-neutral wettability indicated that OSA-UEASS was the promising emulsification stabilizer. The emulsion prepared using OSA-UEASS exhibited better emulsifying activity and emulsion stability and long-term stability for up to 30 days. These amphiphilic granules with improved structure and morphology were used to stabilize a Pickering emulsion.

Effect of carboxymethyl konjac glucomannan coating on the stability and colon-targeted delivery performance of fucoxanthin-loaded gliadin nanoparticles

Fucoxanthin (FUC) is a hydrophobic carotenoid that has a protective effect on the colon. To exert the beneficial effects of FUC in the colon and expand its application in functional food, FUC was encapsulated in carboxymethyl konjac glucomannan (CMKGM)-coated gliadin nanoparticles (Gli-CMKGM NPs) in this paper. Gli-CMKGM NPs were prepared at pH 5.0 with Gli/CMKGM mass ratio of 1:1. The formation of Gli-CMKGM NPs was associated with hydrogen bonding, hydrophobic interactions and electrostatic attractions. Additionally, Gli-CMKGM NPs exhibited good stability to pH, salt, heating and storage. The results showed that FUC had been successfully encapsulated in Gli-CMKGM NPs, and the encapsulation efficiency of FUC-Gli-CMKGM NPs was significantly higher than that of uncoated FUC-Gli NPs. FUC-Gli-CMKGM NPs had a nano-spherical structure, and embedded FUC in Gli-CMKGM NPs improved their stabilities to photodegradation and thermal degradation. Furthermore, in vitro release and in vivo organ distribution studies showed that FUC-Gli-CMKGM NPs had an excellent colon targeting function. Overall, our findings illustrated the promise of CMKGM-coated Gli NPs for constructing targeted delivery systems for FUC.

Fabrication and characterization of superior stable Pickering emulsions stabilized by propylene glycol alginate gliadin nanoparticles

Gliadin, a kind of amphiphilic protein from wheat, has been widely used for stabilizing Pickering emulsions, which is easy to form colloidal particles. Herein, gliadin/propylene glycol alginate (PGA) colloidal particles (GPPs) with different gliadin/PGA ratios were developed and used as emulsifiers to prepare Pickering emulsions with an internal phase of 80% (v/v). The addition of PGA made the GPPs a tree-fruit-like morphology, increasing the particle size and changing the zeta-potential. Hydrogen bond and electrostatic interaction are the major forces between gliadin and PGA. The wettability of GPPs was improved significantly in the presence of PGA. The oil-water contact angle reached 89.5° when the gliadin/PGA ratio was 1 : 1. The emulsion could be maintained at room temperature for 6 months when the oil phase ratio (Φ) was 70%. The high stability of the Pickering emulsion could be attributed to the thin film formed by GPPs on the surface of oil droplets. The improved resistance of algal oil in emulsions against oxidation was proved as the induction time increased six times. In addition, the porous material prepared using GPPs-stabilized emulsion as the template displayed an oil absorption ability of 106.41 g g^-1 and heavy metal adsorption ability of 202.71 mg g^-1. Such performance implies that GPPs are highly efficient food-grade Pickering emulsifiers that may be applied in various fields.

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.

Enhancing the stability of zein/fucoidan composite nanoparticles with calcium ions for quercetin delivery

In this study, zein and fucoidan-based composite nanoparticles were prepared by the antisolvent precipitation method. The effects of different calcium ion (Ca²⁺, 0-3.0 mM) concentrations on the stability of the composite nanosystems loaded with quercetin were studied under different conditions (pH, temperature, salt concentration, and ultraviolet light irradiation), and the composite nanoparticles were characterized. Electrostatic interactions, hydrogen bonding, and hydrophobic interactions are the main forces underlying the formation of composite nanoparticles. The addition of Ca²⁺ led to improved release of the active substances from the composite nanoparticles in simulated digestive solutions (especially when the Ca²⁺ concentration was 1.5 mM). The composite nanosystems based on alcohol-soluble proteins and anionic polysaccharides with added Ca²⁺ can be potentially applied for the delivery of active substances.