Effect of sodium tripolyphosphate incorporation on physical, structural, morphological and stability characteristics of zein and gliadin nanoparticles

Reducing cherry rain-cracking: Enhanced wetting and barrier properties of chitosan hydrochloride-based coating with dual nanoparticles

The synergistic effects of phosphorylated zein nanoparticles (PZNP) and cellulose nanocrystals (CNC) in enhancing the wetting and barrier properties of chitosan hydrochloride (CHC)-based coating are investigated characterized by Fourier Transform Infrared Spectra (FTIR), X-ray Diffraction (XRD), atomic force microscopy and by investigating the mechanical properties, etc., with the aim of reducing cherry rain cracking. FTIR and XRD showed dual nanoparticles successfully implanted into CHC, CHC-PZNP-CNC combined moderate ductility (elongation at break: 7.8 %), maximum tensile strength (37.5 MPa). The addition of PZNP alone significantly improved wetting performance (Surface Tension, CHC: 55.3 vs. CHC-PZNP: 48.9 mN/m), while the addition of CNC alone led to a notable improvement in the water barrier properties of CHC (water vapor permeability, CHC: 6.75 × 10-10 vs. CHC-CNC: 5.76 × 10-10 gm-1 Pa-1 s-1). The final CHC-PZNP-CNC coating exhibited enhanced wettability (51.2 mN/m) and the strongest water-barrier property (5.32 × 10-10 gm-1 Pa-1 s-1), coupled with heightened surface hydrophobicity (water contact angle: 106.4°). Field testing demonstrated the efficacy of the CHC-PZNP-CNC coating in reducing cherry rain-cracking (Cracking Index, Control, 42.3 % vs. CHC-PZNP-CNC, 19.7 %; Cracking Ratio, Control, 34.6 % vs. CHC-PZNP-CNC, 15.8 %). The CHC-PZNP-CNC coating is a reliable option for preventing rain-induced cherry cracking.

Three-Dimensional Cross-Linking Network Coating for the Flame Retardant of Bio-Based Polyamide 56 Fabric by Weak Bonds

Weak bonds usually make macromolecules stronger; therefore, they are often used to enhance the mechanical strength of polymers. Not enough studies have been reported on the use of weak bonds in flame retardants. A water-soluble polyelectrolyte complex composed of polyethyleneimine (PEI), sodium tripolyphosphate (STPP) and melamine (MEL) was designed and utilized to treat bio-based polyamide 56 (PA56) by a simple three-step process. It was found that weak bonds cross-linked the three compounds to a 3D network structure with MEL on the surface of the coating under mild conditions. The thermal stability and flame retardancy of PA56 fabrics were improved by the controlled coating without losing their mechanical properties. After washing 50 times, PA56 still kept good flame retardancy. The cross-linking network structure of the flame retardant enhanced both the thermal stability and durability of the fabric. STPP acted as a catalyst for the breakage of the PA56 molecular chain, PEI facilitated the char formation and MEL released non-combustible gases. The synergistic effect of all compounds was exploited by using weak bonds. This simple method of developing structures with 3D cross-linking using weak bonds provides a new strategy for the preparation of low-cost and environmentally friendly flame retardants.

Investigating the interaction mechanism between gliadin and lysozyme through multispectroscopic analysis and molecular dynamic simulations

The development of stable nanocomplexes based on gliadin and other biopolymers shows potential applications as delivery vehicles in the food industry. However, there is limited study specifically targeting the gliadin-lysozyme system, and their underlying interaction mechanism remains poorly understood. Therefore, the objective of this study was to investigate the binding mechanism between gliadin and lysozyme using a combination of multispectroscopic methods and molecular dynamic simulations. Stable gliadin-lysozyme complex nanoparticles were prepared using an anti-solvent precipitation method with a gliadin-to-lysozyme mass ratio of 2:1 and pH 4.0. The characteristic changes in the UV-visible spectrum of gliadin induced by lysozyme confirmed the complex formation. The analyses of fluorescence, FT-IR spectra, and dissociation tests demonstrated the indispensability of hydrophobic, electrostatic, and hydrogen bonding interactions in the preparation of the composites. Scanning electron microscopy revealed that the surface morphology of the nanoparticles changed from smooth and spherical to rough and irregular with the addition of lysozyme. Furthermore, molecular dynamic simulations suggested that lysozyme bound to the hydrophobic region of gliadin and hydrogen bonding was crucial for the stability of the complex. These findings contribute to the advancement of gliadin-lysozyme complex nanoparticles as an efficient delivery system for encapsulating bioactive compounds in food industry.

A pH-Sensitive Nanoparticle as Reactive Oxygen Species Amplifier to Regulate Tumor Microenvironment and Potentiate Tumor Radiotherapy

Background

Radiotherapy is a widely used clinical tool for tumor treatment but can cause systemic toxicity if excessive radiation is administered. Although numerous nanoparticles have been developed as radiosensitizers to reduce the required dose of X-ray irradiation, they often have limitations, such as passive reliance on radiation-induced apoptosis in tumors, and little consider the unique tumor microenvironment that contributes radiotherapy resistance.

Methods

In this study, we developed and characterized a novel self-assembled nanoparticle containing dysprosium ion and manganese ion (Dy/Mn-P). We systematically investigated the potential of Dy/Mn-P nanoparticles (NPs) as a reactive oxygen species (ROS) amplifier and radiosensitizer to enhance radiation therapy and modulate the tumor microenvironment at the cellular level. Additionally, we evaluated the effect of Dy/Mn-P on the stimulator of interferon genes (STING), an innate immune signaling pathway.

Results

Physicochemical analysis demonstrated the prepared Dy/Mn-P NPs exhibited excellent dispersibility and stability, and degraded rapidly at lower pH values. Furthermore, Dy/Mn-P was internalized by cells and exhibited selective toxicity towards tumor cells compared to normal cells. Our findings also revealed that Dy/Mn-P NPs improved the tumor microenvironment and significantly increased ROS generation under ionizing radiation, resulting in a ~70% increase in ROS levels compared to radiation therapy alone. This enhanced ROS generation inhibited ~92% of cell clone formation and greatly contributed to cytoplasmic DNA exposure. Subsequently, the activation of the STING pathway was observed, leading to the secretion of pro-inflammatory immune factors and maturation of dendritic cells (DCs).

Conclusion

Our study demonstrates that Dy/Mn-P NPs can potentiate tumor radiotherapy by improving the tumor microenvironment and increasing endogenous ROS levels within the tumor. Furthermore, Dy/Mn-P can amplify the activation of the STING pathway during radiotherapy, thereby triggering an anti-tumor immune response. This novel approach has the potential to expand the application of radiotherapy in tumor treatment.

Extraction, identification and application of gliadin from gluten: Impact of pH on physicochemical properties of unloaded- and lutein-loaded gliadin nanoparticles

In the present study, high purity gliadin was extracted from gluten by the marginally modified Osborne method and the effect of different pHs in the aqueous ethanol on the physicochemical properties of unloaded gliadin nanoparticles (UGNs) and lutein-loaded gliadin nanoparticles (LGNs) was investigated. The results revealed that the formation of UGNs and LGNs at diverse pHs was driven by a conjunction of hydrogen bonding, electrostatic interactions and hydrophobic effects, but their dominant roles varied at different pHs. pH also significantly impacted the surface hydrophobicity, secondary structure and aromatic amino acid microenvironment of UGNs and LGNs. LGNs at pH 5.0 and at pH 9.0 exhibited better loading capacity and could reach 9.7884 ± 0.0006 % and 9.7360 ± 0.0017 %, respectively. These two samples also had greater photostability and thermal stability. Half-lives of LGNs at pH 5.0 were 2.185 h and 54.579 h, respectively. Half-lives of LGNs at pH 9.0 were 2.937 h and 49.159 h, respectively. LGNs at pH 5.0 and LGNs at pH 9.0 also had higher bioaccessibility of lutein, with 15.98 ± 0.04 % and 15.27 ± 0.03 %, respectively. These findings yielded precious inspirations for designing innovative lutein delivery system.

Konjac glucomannan/carboxymethyl chitosan film embedding gliadin/casein nanoparticles for grape preservation

Constructing biopolymer-based packaging films with fantastic water resistance and mechanical properties for food preservation is highly desirable and challenging. In this work, Gliadin/Casein nanoparticles (GCNPs) were prepared by pH-driven method and embedded into konjac glucomannan/carboxymethyl chitosan (KC) film matrix to improve the water resistance and mechanical properties of KC film. Gliadin and Casein showed good compatibility and co-assembled to form compact GCNPs clusters through hydrogen bonding and hydrophobic interaction verified by FT-IR spectroscopy, and fluorescence spectroscopy. The particle size and zeta potential of GCNPs was 269.7 nm and -7.6 mV, respectively. The effect of GCNPs on the mechanics, water barrier, thermal stability, and UV-shielding of KC-GCNPs film was investigated. SEM images revealed that GCNPs uniformly distributed into KC film matrix and significantly improved the mechanics (tensile strength: 75.6 MPa, elongation at breaking: 36.7 %), water barrier ability (water contact angle: 91.3°, water vapor permeability: 0.994 g mm/m2 day kPa, water solubility: 52.0 %), thermal stability and UV blocking property of KC-GCNPs film. Furthermore, KC-GCNPs film could also be applied to extend the shelf life of grapes. This paper demonstrated the great potential of GCNPs as functional nanofillers in enhancing the physicochemical properties of KC film.

Phosphorylated walnut protein isolate as a nanocarrier for enhanced water solubility and stability of curcumin

BACKGROUND

The low solubility and poor dispersion of alkaline-extracted walnut protein isolate (AWPI) limit its application as a protein-based carrier for the delivery of poorly soluble nutraceuticals, including curcumin. This work investigated the physicochemical characteristics of phosphorylated walnut protein isolate (PWPI) extracted using sodium tripolyphosphate (STP) and evaluated its encapsulation ability.

RESULTS

The results of phosphorus determination, X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy confirmed the phosphorylation of the extracted PWPI. Circular dichroism (CD) analysis indicated that PWPI contained higher α-helix and lower β-sheet contents than AWPI. The PWPI prepared at pH 9.0 and 11.0 showed significantly improved solubility, similar surface hydrophobicity, and increased surface charges compared to the AWPI. Fluorescence quenching experiments indicated that the binding affinity of curcumin to PWPI was significantly higher than that of AWPI. When bound to PWPI, the solubility of curcumin in aqueous solution was greatly enhanced, with an 8700-fold increase at a nanocomplex concentration of 10 mg mL^-1 . The complexation of curcumin with PWPI significantly improved the storage stability of curcumin. Additionally, the PWPI-curcumin nanocomplexes showed significantly increased antioxidant capacity.

CONCLUSION

Phosphorylated walnut protein isolate showed greatly improved solubility and strong encapsulation ability, making it a promising nanocarrier for curcumin. © 2022 Society of Chemical Industry.

New Perspective on Natural Plant Protein-Based Nanocarriers for Bioactive Ingredients Delivery

The health effects of bioactive substances in the human body are affected by several factors, including food processing conditions, storage conditions, light and heat, among others. These factors greatly limit the stability and bioavailability of bioactive substances. These problems can be solved by a novel protein-based nanocarrier technology, which has the excellent potential to enhance solubility, bioavailability, and the controlled release of bioactive substances. In addition, plant protein has the advantages of economy, environmental protection, and high nutrition compared to animal protein. In this review, the preparation, characterization, and application of plant protein-based nanocarriers are summarized. The research deficiency and future prospects of plant protein nanocarriers are emphasized.

Wheat gluten proteins phosphorylated with sodium tripolyphosphate: Changes in structure to improve functional properties for expanding applications

Poor solubility of wheat gluten proteins (WG) has negative impact on functional attributes such as gelation and emulsification, which limits it use in the food industry. In this study, WG underwent different degrees of phosphorylation using sodium tripolyphosphate (STP). Phosphoric acid groups were successfully incorporated in the WG via covalent bonding (C–N–P and C–O–P) involving hydroxyl and primary amino groups from WG. The introduction of phosphoric acid groups increased the negative charge of phosphorylation-WG, which caused the enhancement of electrostatic repulsion between proteins and reduced the droplet size in emulsions, thereby allowing proteins to be more efficiently dispersed in the solution system. The change of structure induced with phosphorylation improved hydration of protein, making the WG with higher solubility, thereby resulting in the improvement of its emulsification, foaming, thermal stability, and rheological properties. Therefore, WG can be modified by phosphorylation which caused an overall improvement of functional properties, thus facilitating the expansion of WG applications.

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Functional properties of WG were enhanced with phosphorylation (PP).

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The P2p at 133.1 eV and the bonds of C–O–P and C–N–P were found in PP-WG.

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Greater ζ-potential, solubility, viscosity, foaming in PP- WG.

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Phosphorylation increased WG thermal stability and gel properties.

Synthesis, characterization and application of antibacterial lactoferrin nanoparticles

Lactoferrin (L) and gellan gum (G) nanoparticles were produced in different biopolymer proportions through electrostatic complexation to enhance the antimicrobial properties of lactoferrin. The nanoparticles were characterized according to size, charge density, morphology and antimicrobial activity against S. aureus and E. coli, in two different broths to show the effect of the broth composition on the nanoparticle activity. The 9L:1G particles showed the highest positive zeta potential (+21.20 mV) and reduced diameter (92.03 nm) which resulted in a minimum inhibitory concentration six times smaller (0.3 mg/ml) than pure lactoferrin (2 mg/ml). However, the bacteriostatic action of nanoparticles was inhibited in the presence of divalent cations. When applied to strawberries as a coating, lactoferrin nanoparticles extended fruit shelf-life up to 6 days in the presence of carboxymethylcellulose (CMC). Therefore, lactoferrin-gellan gum complexation was proved to be a promising tool to enhance lactoferrin antimicrobial action and broaden its application as a food preserver.

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Positive charged nanoparticles showed 6 times lower MIC than pure lactoferrin.

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Bacteriostatic action of nanoparticles was inhibited in high salt environments.

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Nanoparticle allied to CMC coating extended the shelf life of strawberries.

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The growth of mesophilic bacteria in strawberries was retarded by nanoparticles.

A stable polyamine-modified zein-based nanoformulation with high foliar affinity and lowered toxicity for sustained avermectin release

BACKGROUND

A large amount of pesticides that are not deposited on desired locations due to drift and rolling, endangering the ecological environment and human health. Therefore, it is urgent to develop environmentally friendly and foliar affinity formulations. The design and construction of pesticide nano-delivery system is considered to be an effective way to solve this problem.

RESULTS

In this research, polyamine-modified zein (AM-zein) was synthesized by incorporating ethylenediamine-terminated polyethyleneimine into zein to improve its stability as a nanocarrier, enhance electrostatic force between the carrier and pesticides and plant foliage. Avermectin (AVM)-loaded nanoparticles, containing a high positive charge, were prepared by the anti-solvent method using AM-zein as carrier. The nanoparticles can be stored for 30 days without any significant change in the particle size and stably dispersed at pH 5-9. Compared to the commercial emulsifiable concentrate (EC), nanoparticles dispersions exhibited better leaf affinity, and the retention of dispersion increased from 7.82 to 13.86 mg/cm² . Interestingly, we have discovered for the first time that the ultraviolet (UV) barrier effect of zein increases while prolonging the UV exposure time; 30.47% of the encapsulated AVM remained intact after exposure to UV for 60 min, compared to only 17.13% for the EC. Insecticidal activity of AVM nanoparticles did not improve compared to EC, but they demonstrated significantly lower toxicity against zebrafish.

CONCLUSION

This research opens up a new idea for improving the stability of zein nanoparticles, providing a novel path to deliver pesticides efficiently and eco-friendly. © 2021 Society of Chemical Industry.

Effects of vacuum ultrasonic treatment on the texture of vegetarian meatloaves made from textured wheat protein

To improve the quality of vegetarian meatloaves (VMs) made from textured wheat protein, the effects of different treatments (Vacuum, ultrasound and vacuum ultrasound) were compared in terms of texture, moisture distribution, microstructure and chemical bonding interactions. After vacuum, ultrasonic, and vacuum ultrasonic treatments, the hardness of VMs increased by 78%, 66%, 176% respectively. Scanning electron microscopy (SEM) showed that surface of VMs was smoother and the structure was tighter after vacuum ultrasonic treatment. In addition, magnetic resonance imaging (MRI) analysis showed that the moisture in VMs was evenly distributed after vacuum ultrasonic treatment. According to the optical maps observed by spectrofluorimetry and Fourier transform infrared spectroscopy (FT-IR), the fluorescence value and relative content of β-sheet increased after vacuum ultrasonic treatment. Furthermore, the protein was cross-linked and hydrophobic interactions increased after vacuum ultrasonic treatment. Results showed that texture of VMs after vacuum ultrasonic treatment was closer to that of beef patties.

Formulation and characterization of zein/gum arabic nanoparticles for the encapsulation of a rutin-rich extract from Ruta chalepensis L

Rutin, a plant flavonol characterized by a wide range of biological effects, has limited application in foods because of its low water solubility and scarce bioavailability. This work aimed to investigate the encapsulation of a rutin-rich extract (200.6 ± 1.5 mg/g of rutin) from Ruta chalepensis L. in zein nanoparticles (hydrodynamic diameter of 80-170 nm) prepared by antisolvent precipitation and stabilized by gum arabic (GA). The addition of GA (1:1 mass ratio with zein) significantly reduced the instability phenomena of zein nanoparticles through the deposition of a negatively charged layer as evidenced by the zeta potential and the UV-visible measurement, suggesting an electrostatic interaction between zein and GA. It also contributed to enhancing the encapsulation efficiency of rutin and inducing a rapid release during simulated digestion. These findings show that zein/GA nanoparticles represent a promising delivery system for natural extracts, fabricated through a facile and versatile process.

Modification of pulse proteins for improved functionality and flavor profile: A comprehensive review

Consumers' preference to have a healthy eating pattern has led to an increasing demand for more nutrient-dense and healthier plant-based foods. Pulse proteins are exceptional quality ingredients with potential nutritional benefits, and might act as health-promoting agents for addressing the new-generation foods. However, the utilization of pulse protein in foods has been hampered by its relatively poor functionality and unpleasant flavor. Protein structure modification has been proved to be a useful means to improve the functionality and flavor profile of pulse protein. This paper begins with a brief introduction of hierarchical structure of pulse protein materials to better understand the structure characteristics. A comprehensive review is presented on the current techniques including chemical and enzymatic modifications and molecular breeding on pulse protein structure and functionality/flavor. The mechanism and the limitations and the toxicological concerns of these approaches are discussed. We conclude that understanding protein structure-functionality relationship is extremely valuable in tailoring proteins for specific functional outcomes and expanding the availability of pulse proteins. Furthermore, selective protein modification is a valuable in-depth toolkit for generating novel protein constructs with preferable functional attributes and flavor profiles. Innovative structure modification with special focus on the molecular basis for the exquisite protein designs is a pillar of pulse protein access to the desired functionality.

Gliadin Nanoparticles Pickering Emulgels for β-Carotene Delivery: Effect of Particle Concentration on the Stability and Bioaccessibility

β-carotene is a promising natural active ingredient for optimum human health. However, the insolubility in water, low oral bioavailability, and instability in oxygen, heat, and light are key factors to limit its application as incorporation into functional foods. Therefore, gliadin nanoparticles (GNPs) Pickering emulgels were chosen as food-grade β-carotene delivery systems. The objectives of the present study were to investigate the influence of GNPs concentration on the rheological properties, stability, and simulated gastrointestinal fate of β-carotene of Pickering emulgels. The formulations of Pickering emulgels at low GNPs concentration had better fluidity, whereas at high GNPs concentration, they had stronger gel structures. Furthermore, the thermal stability of β-carotene loaded in Pickering emulgels after two pasteurization treatments was significantly improved with the increase of GNPs concentration. The Pickering emulgels stabilized with higher GNPs concentration could improve the protection and bioaccessibility of β-carotene after different storage conditions. This study demonstrated the tremendous potential of GNPs Pickering emulgels to carry β-carotene.