Double-Interface Binding of Two Bioactive Compounds with Cage-Like Ferritin

Properties regulation and mechanism on ferritin/chitooligosaccharide dual-compartmental emulsions and its application for co-encapsulation of curcumin and quercetin bioactive compounds

Dual-compartmental emulsions, containing multiple chambers, possess great advantages in co-encapsulation of different cargoes. Herein, we reported a stable dual-compartmental emulsion by regulating the ratio of Marsupenaeus japonicus ferritin (MF) and chitooligosaccharide (COS), enabling efficient co-encapsulation of different compounds. The adsorption behavior of MF/COS complex over droplet interface varied at different ratios, thereby exerting an influence on the emulsion properties. Remarkably, emulsions stabilized by MF/COS complex at a ratio of 2:1 exhibited superior stability, as evidenced by no significant creaming or demulsification during storage or heat treatment. The mechanism is that MF/COS2:1 complex can enhance the formation of thicker interfacial layer and dense continuous phase network structure. Additionally, curcumin and quercetin can be co-encapsulated into the emulsions and their retention rates were significantly improved than those in oils, implying the potential of the resulting dual-compartmental emulsions in co-encapsulation and delivery of bioactive compounds.

Casein phosphopeptide interferes the interactions between ferritin and ion irons

Ferritin, a vital protein required to store iron in a cage-like structure, is critical for maintaining iron balance. Ferritin can be attacked by free radicals during iron reduction and release, thereby leading to oxidative damage. Whether other biomacromolecules such as casein phosphopeptides (CPP) could influence the ferritin's function in iron oxidation and release and affect the ferritin stability remains unclear. This study aims to investigate the effect of CPP on the ferritin‑iron ion interaction, thereby focusing on role of CPP on ferritin stability. Results showed that CPP weakened the iron oxidation activity of ferritin but promoted iron release. Moreover, CPP could effectively chelate iron, capture hydroxyl radicals, and reduce the degradation of ferritin. This study highlights the role of CPP in the ferritin‑iron relationship, and lays a foundation for understanding the interaction between ferritin, peptides, and metal ions.

Food nanotechnology: opportunities and challenges

Food nanotechnology, which applies nanotechnology to food systems ranging from food production to food processing, packaging, and transportation, provides tremendous opportunities for conventional food science and industry innovation and improvement. Although great progress and rapid growth have been achieved in food nanotechnology research owing to the unique food features rendered by nanotechnology, at a fundamental level, food nanotechnology is still in its initial stages and the potential adverse effects of nanomaterials are still a controversial problem that attract public attention. Food-derived nanomaterials, compared to some inorganic nanoparticles and synthetic organic macromolecules, can be digested rapidly and produce similar digestion products to those produced normally, which become the mainstream and trend for food nanotechnology in practical applications, and are expected to be a vital tool for addressing the security problem and easing public concerns. These food-derived materials enable the favourable characteristics of nanostructures to be combined with the safety, biocompatibility, and bioactivity of natural food. Very recently, diverse food-derived nanomaterials have been explored and widely applied in multiple fields. Herein, we thoroughly summarize the fabrication and development of nanomaterials for use in food technology, as well as the recent advances in the improvement of food quality, revolutionizing food supply, and boosting food industries based on foodborne nanomaterials. The current challenges in food nanotechnology are also discussed. We hope this review can provide a detailed reference for experts and food manufacturers and inspire researchers to participate in the development of food nanotechnology for highly efficient food industry growth.

Dual Decoration of Ferritin Nanocages by Caffeic Acid and Betanin with Covalent and Noncovalent Approaches: Structure and Stability Analyses

Ferritin is a cage-like protein with modifiable outer and inner surfaces. To functionalize ferritin with preferable carrier applications, caffeic acid was first covalently bound to the soybean ferritin outer surface to fabricate a caffeic acid-ferritin complex (CFRT) by alkali treatment (pH 9.0). A decreased content of free amino acid (0.34 μmol/mg) and increased polyphenol binding equivalent (63.76 nmol/mg) indicated the formation of CFRT (ferritin/caffeic acid, 1:80). Fluorescence and infrared spectra verified the binding of caffeic acids to the ferritin structure. DSC indicated that the covalent modification enhanced the thermal stability of CFRT. Besides, CFRT maintained the typically spherical shape of ferritin (12 nm) and a hydration radius of 7.58 nm. Moreover, the bioactive colorant betanin was encapsulated in CFRT to form betanin-loaded CFRT (CFRTB), with an encapsulation rate of 15.5% (w/w). The betanin stabilities in CFRTB were significantly improved after heat, light, and Fe3+ treatments, and its red color retention was enhanced relative to the free betanin. This study delves into the modifiable ferritin application as nanocarriers of dual molecules and gives guidelines for betanin as a food colorant.

Multifaceted Applications of Ferritin Nanocages in Delivering Metal Ions, Bioactive Compounds, and Enzymes: A Comprehensive Review

Ferritin, a distinctive iron-storage protein, possesses a unique cage-like nanoscale structure that enables it to encapsulate and deliver a wide range of biomolecules. Recent advances prove that ferritin can serve as an efficient 8 nm diameter carrier for various bioinorganic nutrients, such as minerals, bioactive polyphenols, and enzymes. This review offers a comprehensive summary of ferritin's structural features from different sources and emphasizes its functions in iron supplementation, calcium delivery, single- and coencapsulation of polyphenols, and enzyme package. Additionally, the influence of innovative food processing technologies, including manothermosonication, pulsed electric field, and atmospheric cold plasma, on the structure and function of ferritin are examined. Furthermore, the limitations and prospects of ferritin in food and nutritional applications are discussed. The exploration of ferritin as a multifunctional protein with the capacity to load various biomolecules is crucial to fully harnessing its potential in food applications.

Sustained release of chlorogenic acid by co-encapsulation of sodium alginate binding to the Northern pike (Esox Lucius) liver ferritin

Ferritin has a unique hollow spherical structure, which makes it a promising nanocarrier for food functional substances. In this study, a new ferritin was successfully extracted from the liver of Northern pike, purified, and identified. We used the reversible self-assembly characteristics of ferritin to fabricate chlorogenic acid (CA)-loaded apoferritin (Apo) complex (Apo-CA) and sodium alginate (SA)-apoferritin (Apo) co-encapsulate system. Apo-CA was encapsulated into the SA system to form SA-Apo-CA. The fabricated composites were analyzed using particle size, UV-Vis absorption spectroscopy, fluorescence spectroscopy, flourier transform infrared spectroscopy and transmission electron microscope. Physicochemical property of analysis confirmed th successful preparation of Apo-CA/SA-Apo-CA and improved thermal and UV radiation stability. The effect of sustained-release of CA were tested in vitro of simulated gastrointestinal tract digestion. SA-Apo-CA exhibited greater release ability than unencapsulated CA and Apo-CA. This study provides a new strategy for designing a multilayer delivery system with improved stability and sustained-release property.

Phytoferritin functions in two interface-loading of natural pigment betanin and caffeic acid with enhanced color stability and the sustained release of betanin

Betanin, a natural red pigment, is sensitive and prone to fading and discoloration, affecting its stability and bioavailability. Phytoferritin is a nano-diameter protein with unique interior-/exterior-interfaces. By the unique interfaces and pH-induced self-assembly of ferritin, a ferritin-betanin complex (FB) with an encapsulation efficiency of 17.66 ± 1.24% was prepared. The caffeic acid-FB (CFB) was further fabricated by attaching ferritin with caffeic acid, and the binding number n of caffeic acid was 88.47 ± 9.49, with a binding constant K of (1.63 ± 0.33) × 104 M-1. Fluorescence and Fourier transform infrared analysis indicated that the encapsulation of betanin and the binding of caffeic acid influenced the ferritin structure. The interaction between caffeic acid and ferritin was mainly through van der Waals forces and hydrogen bonds. TEM and DLS showed that the globular structure and diameter (12 nm) remained in CFB. Furthermore, the ferritin and caffeic acid exhibited a synergistic effect in enhancing thermal, light, and ferric ion stabilities, and controlled the betanin release in a more sustained manner in the simulated gastrointestinal tract. In addition, the antioxidant capacity of CFB was enhanced compared with free betanin. This study promotes the bioavailability of betanin by two interface-loading of ferritin, and guides the use of ferritin nanoparticles as a nanocarrier for pigment stabilization.

Modifications of Thermal-Induced Northern Pike (Esox lucius) Liver Ferritin on Structural and Self-Assembly Properties

Ferritin, as an iron storage protein, regulates iron metabolism and delivers bioactive substances. It has been regarded as a safe, new type of natural iron supplement, with high bioavailability. In this paper, we extracted and purified ferritin from northern pike liver (NPLF). The aggregation stabilities, assemble properties, and structural changes in NPLF were investigated using electrophoresis, dynamic light scattering (DLS), circular dichroism (CD), UV–Visible absorption spectroscopy, fluorescence spectroscopy, and transmission electron microscopy (TEM) under various thermal treatments. The solubility, iron concentration, and monodispersity of NPLF all decreased as the temperature increased, and macromolecular aggregates developed. At 60 °C and 70 °C, the α-helix content of ferritin was greater. The content of α-helix were reduced to 8.10% and 1.90% at 90 °C and 100 °C, respectively, indicating the protein structure became loose and lost its self-assembly ability. Furthermore, when treated below 80 °C, NPLF maintained a complete cage-like shape, according to the microstructure. Partially unfolded structures reassembled into tiny aggregates at 80 °C. These findings suggest that mild thermal treatment (80 °C) might inhibit ferritin aggregation while leaving its self-assembly capacity unaffected. Thus, this study provides a theoretical basis for the processing and use of NPLF.

Ferritin nanocage based delivery vehicles: From single-, co- to compartmentalized- encapsulation of bioactive or nutraceutical compounds

Bioactive or nutraceutical ingredients have been widely used in pursuit of health and well-being. However, the environmental instability, poor solubility and bioavailability, and unspecific delivery highly limited their practical values. By virtue of the unique shell-like structure, definite disassembly/reassembly behavior, and excellent safety profile of ferritin protein, it stands out among of various nano-materials and is emerging as one of the most promising vehicles for the encapsulation and delivery of bioactive ingredients or drugs. In this review, we present a systematic overview of recent advances of ferritin-based delivery systems from single-encapsulation, co-encapsulation, to compartmentalized-encapsulation of bioactive ingredients or drugs. Different encapsulation strategies for cargo loading as well as their advantages and drawbacks have been critically reviewed. This study emphasized the importance of the construction of compartmentalized delivery systems through the usage of ferritin nanocages, which exhibit great potential for facilitating the synergistic functionality of different types of cargos. Lastly, the applications of ferritin nanocages for physicochemical improvements and functionality achievements of loaded cargos are summarized. In conclusion, ferritin protein nanocages not only are excellent nanocarriers, but also can act as"multi-seated" vehicles for co-encapsulation and compartmentalized encapsulation of different cargos simultaneously.

Advances in Rational Protein Engineering toward Functional Architectures and Their Applications in Food Science

Protein biomolecules including enzymes, cagelike proteins, and specific peptides have been continuously exploited as functional biomaterials applied in catalysis, nutrient delivery, and food preservation in food-related areas. However, natural proteins usually function well in physiological conditions, not industrial conditions, or may possess undesirable physical and chemical properties. Currently, rational protein design as a valuable technology has attracted extensive attention for the rational engineering or fabrication of ideal protein biomaterials with novel properties and functionality. This article starts with the underlying knowledge of protein folding and assembly and is followed by the introduction of the principles and strategies for rational protein design. Basic strategies for rational protein engineering involving experienced protein tailoring, computational prediction, computation redesign, and de novo protein design are summarized. Then, we focus on the recent progress of rational protein engineering or design in the application of food science, and a comprehensive summary ranging from enzyme manufacturing to cagelike protein nanocarriers engineering and antimicrobial peptides preparation is given. Overall, this review highlights the importance of rational protein engineering in food biomaterial preparation which could be beneficial for food science.

Succinylated ferritin as a novel nanocage-like vehicle of polyphenol: Structure, stability, and absorption analysis

Ferritin, a protein with an 8-nm cage structure, can encapsulate and deliver bioactive molecules. In this study, succinylation was adopted to modify plant ferritin to fabricate succinylated red been ferritin (SRBF) at pH 8.0. The SRBF was retained as a cage-like shape (12 nm diameter), while its secondary structure was altered, rendering higher negative charge accompanies by decreased surface hydrophobicity. The SRBF also demonstrated favorable property of reversible assembly regulated by pH-transitions (pH 2.0/7.0), thus enabled successful encapsulation of epigallocatechin gallate (EGCG) for fabrication of EGCG-loaded SRBF complexes with a diameter of ~12 nm. Succinylation enhanced the thermal stabilities of ferritin and the embedded EGCG. Moreover, SRBF markedly improved the transport efficiency of EGCG in Caco-2 monolayers relative to EGCG and that encapsulated in unmodified ferritin. These findings have extended the succinylation reaction for the cage-like protein modification, and facilitated the usage of ferritin variant in delivery of bioactive molecules.

Interaction mechanism of ferritin protein with chlorogenic acid and iron ion: The structure, iron redox, and polymerization evaluation

Ferritin is an iron-containing protein and functions in the maintenance of iron balance in organisms. Currently the interaction among ferritin, ion iron, and food bioactive compounds is still unclear. In this study, the mechanism underlying the interaction of ferritin, ion iron, and chlorogenic acid was investigated, as well as the effect of chlorogenic acid on the physicochemical properties of ferritin. The results showed that chlorogenic acid could interact with Fe(III) to form chlorogenic acid-Fe(III) complexes, which then bonded with ferritin via hydrogen bonds in the ferritin-chlorogenic acid-Fe(III) complexes. The chlorogenic acid showed a high efficiency in Fe(II) chelation and hydroxyl radical (•OH) capture, and could promote iron oxidation and iron release induced by ferritin. Chlorogenic acid could also effectively reduce the polymerization extent of ferritin induced by Fe(III) and Fe(II). This study elucidates the interactions of multiple components in foodstuffs by using a protein-metal-polyphenol model.