Influence of Manothermosonication on the Physicochemical and Functional Properties of Ferritin as a Nanocarrier of Iron or Bioactive Compounds

Enhancing techno-functional attributes of plant protein and curcumin complexation: A comparative examination of Maillard conjugation induced by manothermosonication and ultrasonication

The Maillard conjugation of hemp protein with d-xylose was studied, focusing on the influence of ultrasonic waves, processing time, and pressure. Cavitation-driven processes, including ultrasonication (US) and manothermosonication (MTS), were found to impact the degree of grafting, functional characteristics, and structural alterations, affecting conjugation efficiency. The glycation of hemp protein with xylose assisted with US and MTS was investigated under varying pressures. MTS- and US-assisted glycation processes result in 4.22- and 1.64-fold higher degrees of grafting compared to the classical method within a short time frame. The MTS procedures also improved solubility (+3.6-fold), emulsion (+15-fold), and foaming (+1.7-fold) properties, especially at optimized pressure levels, compared to classical conjugates. Furthermore, the complexation of MTS-assisted conjugates with curcumin (Cur) enhanced Cur stability by more than 1.4-fold compared to the classical procedure during 20-day storage at 4 oC. The findings suggest potential applications in the pharmaceutical industry, active dairy/meat analog development, and gel formulation.

The application of ferritin in transporting and binding diverse metal ions

The ferritin cage can not only load iron ions in its inner cavity, but also has the capacity to carry other metal ions, thus constructing a new biological nano-transport system. The nanoparticles formed by ferritin and minerals can be used as ingredients of mineral supplements, which overcome the shortcomings of traditional mineral ingredients such as low bioavailability. Moreover, ferritin can be used to remove heavy metal ions from contaminated food. Silver and palladium nanoparticles formed by ferritin are also applied as anticancer agents. Ferritin combined with metal ions can be also used to detect harmful substances. This review aims to provide a comprehensive overview of ferritin's function in transporting and binding metal ions, and discusses the limitations and future prospects, which offers valuable insights for the application of ferritin in mineral supplements, food detoxifiers, anticancer agents, and food detections.

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.

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.

Genipin-mediated subunit-subunit crosslinking of ferritin nanocages: Structure, properties, and its application for food bioactive compound sealing

Ferritin proteins are promising nano-carriers for bioactive compound delivery. However, the disassembly properties under acidic/alkaline conditions pose risks of cargo leakage. Herein, genipin-mediated chemical crosslinking method was provided as an alternative and effective strategy to construct robust ferritin nanocarrier through controlled-intramolecular conjugation. As indicated by SDS-/Native- PAGE, the crosslinking degree gradually increased with incubating time prolonging. CD results showed that the cross-linking would decrease α-helix content from 78.4 % to 52.7 % upon 6 h incubation. However, TEM images showed that the genipin-modification has subtle influence on its shell-like structure. Remarkably, the cross-linking can be well controlled by intramolecular subunit-subunit conjugation rather than intermolecular conjugation, giving an excellent monodispersity. Importantly, the covalent cross-linking can tight neighboring subunits and inhibit its disassociation, finally inhibiting the leakage of encapsulated-cargos from ferritin cavity under acidic environments. Such findings suggested that the genipin-mediated cross-linking strategy can fabricate robust nano-carriers for bioactive compound delivery.

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.

Hyperthermostability of prawn ferritin nanocage facilitates its application as a robust nanovehicle for nutraceuticals

The favorable physicochemical properties are essential for the application of protein-based nanovehicles in the field of biomaterials. Herein, we found that the thermal stability of Marsupenaeus japonicus ferritin (MjFer) (T_m = 109.1 ± 0.4 °C) is markedly higher than human H-chain ferritin (HuHF) (T_m = 87.7 ± 0.3 °C), although they share a high structural similarity. Multiple results indicated that the promoted thermal stability of MjFer is mainly derived from the salt bridges located at the C₃ interface. Consequently, MjFer exhibits strong protective effects on encapsulated curcumin upon exposure at high temperatures. In contrast, most of the curcumin loaded HuHF composites precipitated rapidly under the same conditions. These findings elucidated the molecular mechanism of the hyperthermostability of MjFer and illustrated that MjFer could act as a robust insulation nanocarrier for bioactive compounds against various thermal treatments.

Fabrication of a ferritin-casein phosphopeptide-calcium shell-core composite as a novel calcium delivery strategy

Plant ferritin has a natural cage-like nanospace for carrying bioactive ingredients. By taking advantage of the calcium binding ability of casein phosphopeptide (CPP) and the cage-like conformation of plant ferritin, a ferritin-CPP shell-core complex (FC) was fabricated with the reversible self-assembly character of ferritin induced by a pH 2.0/7.0 transition strategy. The FC-calcium composite (FCC) was further fabricated by binding of the FC with calcium ions. When the same amount of calcium was loaded, the calcium binding capacity of the FCC was 28.13 ± 1.65%, which was significantly higher than that of ferritin and CPP alone. Fluorescence and Fourier transform infrared analysis indicated that the CPP encapsulation and the calcium binding in the FCC influenced the ferritin structure. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) results showed that the spherical morphology and the 12 nm-diameter size were sustained in the FC and FCC. Moreover, the FCC as a transport carrier could increase the precipitation time of calcium phosphate, and the encapsulated calcium could be released in a more sustained manner as compared with ferritin and CPP under simulated in vitro gastrointestinal conditions. This study presents a novel calcium delivery strategy based on the ferritin cage and CPP, which will improve the applicability of ferritin and CPP and enhance the bioavailability of calcium ions.

Chaotrope-Controlled Fabrication of Ferritin-Salvianolic Acid B- Epigallocatechin Gallate Three-Layer Nanoparticle by the Flexibility of Ferritin Channels

Phytoferritin has a natural cagelike architecture for carrying bioactive molecules, and it is uniquely suited to function as a carrier due to its multiple interfaces and channels. In this study, a novel approach was proposed to prepare ferritin-salvianolic acid B-epigallocatechin gallate (EGCG) three-layer nanoparticles (FSE) through the steric hindrance of ferritin channels. Urea (30 mM) could expand the ferritin channel size evidenced by the improved iron release rate v_o and promote the EGCG penetration into the ferritin cavity without disassembly of the ferritin cage. The encapsulation ratio of EGCG was 16.0 ± 0.14% (w/w). Salvianolic acid B attached to the outer interface of ferritin through weak bonds with a binding constant of (2.91 ± 0.04) × 10⁵ M^-1. The FSE maintained a spherical structure with a diameter of 12 nm. Moreover, when subjected to heat (40-70 °C) there was a significant increase in the stability of EGCG in the FSE due to the binding of salvianolic acid B. Through this interesting approach, two molecules are simultaneously attached and encapsulated in ferritin in a multilayer form under moderate conditions, which is conducive to the protection of unstable molecules for potential encapsulation and delivery utilization.

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.

Internal cavity amplification of shell-like ferritin regulated with the change of the secondary and tertiary structure induced by PEF technology

In this study, the effect of pulsed electric field (PEF) on apparent morphology and molecular structure of shell-like ferritin obtained from horse spleen was determined by circular dichroic (CD), fluorescence spectroscopy, Raman spectroscopy, cold field emission scanning electron microscopy (CF-SEM) and transmission electron microscopy (TEM), and verified by molecule dynamics (MD) simulation. After PEF treatment, the α-helix content of the samples reached a minimum value at 10 kV/cm, which indicated that the ferritin structure has been partially unfolded. However, the α-helix content peaked again after resting for 2 h at 25 ± 1 °C. This indicated that the PEF-treated ferritin tended to restore its original spherical morphology probably owing to the reversible assembly characteristic of ferritin. In addition, microstructure analysis revealed that ferritin particles aggregated after PEF treatment. Therefore, PEF treatment could induce the "exposure" of hydrophobic amino acids and conversion of disulfide bond configuration, and consequently, regulate the internal cavity stability of ferritin. The research will be beneficial to expand the application of PEF treatment in the modification of protein structure, and provide a theoretical basis for the application of ferritin as a carrier of bioactive molecules in food.

Food preservation techniques and nanotechnology for increased shelf life of fruits, vegetables, beverages and spices: a review

Food wastage is a major issue impacting public health, the environment and the economy in the context of rising population and decreasing natural resources. Wastage occurs at all stages from harvesting to the consumer, calling for advanced techniques of food preservation. Wastage is mainly due to presence of moisture and microbial organisms present in food. Microbes can be killed or deactivated, and cross-contamination by microbes such as the coronavirus disease 2019 (COVID-19) should be avoided. Moisture removal may not be feasible in all cases. Preservation methods include thermal, electrical, chemical and radiation techniques. Here, we review the advanced food preservation techniques, with focus on fruits, vegetables, beverages and spices. We emphasize electrothermal, freezing and pulse electric field methods because they allow both pathogen reduction and improvement of nutritional and physicochemical properties. Ultrasound technology and ozone treatment are suitable to preserve heat sensitive foods. Finally, nanotechnology in food preservation is discussed.

Ferritin Nanocage: A Versatile Nanocarrier Utilized in the Field of Food, Nutrition, and Medicine

Compared with other nanocarriers such as liposomes, mesoporous silica, and cyclodextrin, ferritin as a typical protein nanocage has received considerable attention in the field of food, nutrition, and medicine owing to its inherent cavity size, excellent water solubility, and biocompatibility. Additionally, ferritin nanocage also serves as a versatile bio-template for the synthesis of a variety of nanoparticles. Recently, scientists have explored the ferritin nanocage structure for encapsulation and delivery of guest molecules such as nutrients, bioactive molecules, anticancer drugs, and mineral metal ions by taking advantage of its unique reversible disassembly and reassembly property and biomineralization. In this review, we mainly focus on the preparation and structure of ferritin-based nanocarriers, and regulation of their self-assembly. Moreover, the recent advances of their applications in food nutrient delivery and medical diagnostics are highlighted. Finally, the main challenges and future development in ferritin-directed nanoparticles’ synthesis and multifunctional applications are discussed.

Accelerating aroma formation of raw soy sauce using low intensity sonication

Sonication was applied to accelerate aroma formation and shorten fermentation time of soy sauce. Effects of sonication at 68 kHz on the aroma and aroma-producing Zygosaccharomyces rouxii and Tetragenococcus halophilus in moromis were investigated using sensory evaluation, SPME-GC-olfactometry/MS, viable cell counting and scanning electron microscopy. The sensory scores of caramel-like, fruity, alcoholic, floral, malty, smoky, sour and overall aroma in sonicated moromis were enhanced by 23.4%, 23.2%, 13.6%, 12.8%, 7.6%, 6.3%, 5.6% and 14.4%, respectively. Sensory scores of samples fermented for 90-180 days were higher than those of controls fermented for 180 days, suggesting that sonication could reduce fermentation time by 90 days. Thirty-four aroma-active compounds were detected from 85 volatile compounds in soy sauces. Sonication accelerated and elevated the formation of aroma compounds by chemical reactions. It also markedly increased the reproduction and cell permeability of both microorganisms in moromis, which favored the formation of aroma compounds by both strains.