Ovotransferrin, an alternative and potential protein for diverse food and nutritional applications.

Ovotransferrin(OVT)is a protein found in many types of egg white and has a wide range of functional properties. It has 50% homology with human/bovine lactoferrin, and is expected to be one of the most important alternative proteins for use in food and nutritional applications. This paper mainly reviews the structural characteristics and chemical properties of OVT, as well as its extraction and purification methods. It also systematically describes the various biological activities of OVT and its applications in food and medical industries. The challenges and limitations in the research of OVT were suggested. This review recommends some possible methods such as nanoparticle carriers and microencapsulation to improve the bioavailability and stability of OVT. In addition, this review highlights several strategies to overcome the limitations of OVT in terms of preparation and purification. This review systematically summarizes the recent advances in OVT and will provide guidance for the its development for food and nutritional applications.

Efficient H2O2 Synthesis through a Two-Electron Oxygen Reduction Reaction by Electrocatalysts.

The two-electron oxygen reduction reaction (2e-ORR) for the sustainable synthesis of hydrogen peroxide (H2O2) has demonstrated considerable potential for local production of this environmentally friendly chemical oxidant on small, medium, and large scales. This method offers a promising alternative to the energy-intensive anthraquinone approach, placing a primary emphasis on the development of efficient electrocatalysts. Improving the efficiency of electrocatalysts and uncovering their catalytic mechanisms are essential steps in achieving high 2e-ORR activity, selectivity, and stability. This comprehensive review summarizes recent advancements in electrocatalysts for in-situ H2O2 production, providing a detailed overview of the field. In particular, the review delves into the design, fabrication, and investigation of catalytic active sites contributing to H2O2 selectivity. Additionally, it highlights a range of electrocatalysts including pure metals and alloys, transition metal compounds, single-atom catalysts, and carbon-based catalysts for the 2e-ORR pathway. Finally, the review addresses significant challenges and opportunities for efficient H2O2 electrosynthesis, as well as potential future research directions.

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.

Ultrasound assisted fabrication of the yeast protein-chitooligosaccharide-betanin composite for stabilization of betanin.

Betanin, a water-soluble colorant, is sensitive to light and temperature and is easily faded and inactivated. This study investigated the formation of yeast protein-chitooligosaccharide-betanin complex (YCB) induced by ultrasound treatment, and evaluated its protective effect on the colorant betanin. Ultrasound (200-600 W) increased the surface hydrophobicity and solubility of yeast protein, and influenced the protein's secondary structure by decreasing the α-helix content and increasing the contents of ß-sheet and random coil. The ultrasound treatment (200 W, 15 min) facilitated binding of chitooligosaccharide and betanin to the protein, with the binding numbers of 4.26 ± 0.51 and 0.61 ± 0.06, and the binding constant of (2.73 ± 0.25) × 105 M-1 and (3.92 ± 0.10) × 104 M-1, respectively. YCB could remain the typical color of betanin, and led to a smaller and disordered granule morphology. Moreover, YCB exhibited enhanced thermal-, light-, and metal irons (ferric and copper ions) -stabilities of betanin, protected the betanin against color fading, and realized a controlled release in simulated gastrointestinal tract. This study extends the potential application of the fungal proteins for stabilizing bioactive molecules.

Highly Ordered Hierarchical Macro-Mesoporous Carbon-Supported Cobalt Electrocatalyst for Efficient Oxygen Evolution Reaction.

Metal-organic frameworks (MOFs) and their derivatives have been extensively employed in Oxygen Evolution Reaction (OER) catalysts due to their significantly larger specific surface areas, distinct metal centers, and well-organized porous structures. However, the microporous structure of MOFs and their derivatives presents mass transfer resistance, limiting their further development. Drawing inspiration from hierarchical structures allowing for the transport and exchange of substances in the biological world, we designed and fabricated biomimetic layered porous structures within ZIF-67 and its derivatives. Based on this, we achieved a three-dimensional ordered layered porous nitrogen-doped carbon-coated magnetic cobalt catalyst (3DOLP Co@NDC) with a biomimetic pore structure. It is found that the 3DOLP Co@NDC (352 mV @10 mA cm-1) was better than Co@NDC (391 mV @10 mA cm-1). The introduction of a three-dimensional ordered layered porous structure is conducive to increasing the specific surface area of the material, increasing the electrochemical active area, and improving the catalytic performance of the material. The introduction of a three-dimensional ordered layered porous structure would help to build a bionic grade pore structure. The existence of biomimetic grade pore structure can effectively reduce the mass transfer resistance, improve the material exchange efficiency, and accelerate the reaction kinetics.