Surface activity and safety of deamidated zein peptides

Nanoencapsulation of vitamin D3 by ultrasonic pretreated zein hydrolysates: Stability improvement in food models

This work is aimed to assess the effect of ultrasonic pre-treatment on the enzymatic hydrolysis of zein and the nanoencapsulation of vitamin D3 (VitD3) by zein hydrolysates (ZH). The ultrasonic pre-treatment significantly increased the degree of hydrolysis by and the α-helix, β-sheet, β-turns contents, and random coils were enhanced by ultrasonic pre-treatment. VitD3 was successfully encapsulated by the developed ZH nanoparticles (NPs), with an encapsulation efficiency of 95.23 ± 1.78 %. The surface charge and particle size of the nanoparticles (NPs) were -5.45 ± 1.76 mV and 39.43 ± 7.96 nm, respectively. The detailed morphology study of NPs showed a regular spherical morphology, and the chemical structures of NPs were characterized by Fourier Transform Infrared Red spectroscopy. Additionally, the developed NPs were added to milk, which exhibited high stability after one month of storage. In conclusion, the VitD3-loaded ZHNPs had considerable potential for fortifying different foodstuffs.

Recent Advances in Efficient Lutein-Loaded Zein-Based Solid Nano-Delivery Systems: Establishment, Structural Characterization, and Functional Properties

Plant proteins have gained significant attention over animal proteins due to their low carbon footprint, balanced nutrition, and high sustainability. These attributes make plant protein nanocarriers promising for applications in drug delivery, nutraceuticals, functional foods, and other areas. Zein, a major by-product of corn starch processing, is inexpensive and widely available. Its unique self-assembly characteristics have led to its extensive use in various food and drug systems. Zein's functional tunability allows for excellent performance in loading and transporting bioactive substances. Lutein offers numerous bioactive functions, such as antioxidant and vision protection, but suffers from poor chemical stability and low bioavailability. Nano-embedding technology can construct various zein-loaded lutein nanodelivery systems to address these issues. This review provides an overview of recent advances in the construction of zein-loaded lutein nanosystems. It discusses the fundamental properties of these systems; systematically introduces preparation techniques, structural characterization, and functional properties; and analyzes and predicts the target-controlled release and bioaccessibility of zein-loaded lutein nanosystems. The interactions and synergistic effects between Zein and lutein in the nanocomplexes are examined to elucidate the formation mechanism and conformational relationship of zein-lutein nanoparticles. The physical and chemical properties of Zein are closely related to the molecular structure. Zein and its modified products can encapsulate and protect lutein through various methods, creating more stable and efficient zein-loaded lutein nanosystems. Additionally, embedding lutein in Zein and its derivatives enhances lutein's digestive stability, solubility, antioxidant properties, and overall bioavailability.

Enhanced oral bioavailability of cannabidiol by flexible zein nanoparticles: in vitro and pharmacokinetic studies

Introduction

Cannabidiol (CBD) has a variety of pharmacological effects including antiepileptic, antispasmodic, anxiolytic and anti-inflammatory among other pharmacological effects. However, since CBD is a terpene-phenolic compound, its clinical application is limited by its poor water solubility, low stability, and low bioavailability.

Methods

In this study, we used several strategies to address the above problems. Hydrochloric acid was used to modify zein to improve the molecular flexibility. Flexible zein nanoparticles (FZP-CBD) loaded with CBD was prepared to improve the stability and bioavailability of CBD. The parameters were evaluated in terms of morphology, particle size (PS), polydispersity index (PDI), zeta potential (ZP), entrapment efficiency (EE%), loading capacity (LC%), and storage stability. Simulated gastrointestinal fluid release experiment and bioavailability assay were applied in the evaluation.

Results

The simulated gastrointestinal fluid experiment showed that the release rates of FZP-CBD and natural zein nanoparticles (NZP-CBD) loaded with CBD were 3.57% and 89.88%, respectively, after digestion with gastric fluid for 2 h, 92.12% and 92.56%, respectively, after intestinal fluid digestion for 2 h. Compared with NZP-CBD, the C max of FZP-CBD at 3 different doses of CBD was increased by 1.7, 1.3 and 1.5 times respectively, and AUC0-t was increased by 1.4, 1.1 and 1.7 times respectively, bioavailability (F) was increased by 135.9%, 114.9%, 169.6% respectively.

Discussion

The experimental results showed that FZP-CBD could protect most of the CBD from being released in the stomach, and then control its release in the intestines, promote the absorption of CBD in the small intestine, and increase the bioavailability of CBD. Therefore, FZP-CBD could improve the utilization value of CBD and provide a new idea for the application of CBD in medicine and pharmacy.

Improvement of amphipathic properties with molecular structure unfolding and activation of cottonseed protein as ultra stable and safe emulsifier by deamidation

By-product cottonseed proteins are excellent options for numerous applications due to their superior properties and lower cost. However, its complex folded structure and large molecular weight lead to lower reactivity and insufficient amphiphilicity. Cottonseed protein isolate (CPI) is less-soluble in water. Therefore, we improved the amphiphilicity of CPI with associated hydrolysis, molecular structure unfolding, and activation by alkaline-induced deamidation (at 24, 36, and 72 h) and produced three cottonseed protein hydrolysates CPH 24, 36, and 72. FTIR/UV-CD measurements confirmed the conformational changes and conversion of the structural content. Particle size decreased 2503.4-771.8 nm, while surface hydrophobicity (133.5-326.7), carboxyl content (1.13 × 10־3-2.09 × 10־3), and flexibility increased, signifying hydrolysis, unfolding, and amphiphilicity improvement. Longer deamidation (CPH 72) exhibited the best properties, its prepared emulsions were long-term stable under all the environmental stresses without visible phase separation after at least 40 days of storage except at pH 4. Compared to CPI, it had smaller droplets (939.3-264.9 nm) and larger absolute ζ-potential (-26.5 to -58.0 mV). From the in-vitro cytotoxicity test, deamidated CPI is extremely safer than commonly used synthetic surfactants. This research provides a new method for producing multifunctional emulsifiers from CPI, which could be utilized in the development of functional foods/non-foods.

Industrial Application of Protein Hydrolysates in Food

Protein hydrolysates, which may be produced by the protein in the middle of the process or added as an ingredient, are part of the food formula. In food, protein hydrolysates are found in many forms, which can regulate the texture and functionality of food, including emulsifying properties, foaming properties, and gelation. Therefore, the relationship between the physicochemical and structural characteristics of protein hydrolysates and their functional characteristics is of significant importance. In recent years, researchers have conducted many studies on the role of protein hydrolysates in food processing. This Review explains the relationship between the structure and function of protein hydrolysates, and their interaction with the main ingredients of food, to provide reference for their development and further research.

Corn peptides improved obesity-induced non-alcoholic fatty liver disease through relieving lipid metabolism, insulin resistance and oxidative stress

Non-alcoholic fatty liver disease (NAFLD) is increasingly threatening human health. The remarkable effects of corn peptides (CPs) as bioactive peptides on liver protection have attracted much attention. Nevertheless, the specific effect of CPs on NAFLD remains unclear. The present study was designed to investigate the efficacy of CPs in the prevention and auxiliary treatment of high-fat diet (HFD)-induced NAFLD in SD rats, and puerarin was used as the positive control. SD rats were fed a high-fat diet to establish the NAFLD rat model, and LO2 cells were treated with a high concentration of fructose to simulate the NAFLD cell model. NAFLD was comprehensively examined in terms of body weight, liver function markers, serum biochemistry and liver histology. Protein expression was determined using western blot analysis. The results of animal experiments showed that CPs could effectively inhibit the rate of weight gain, reduce the blood lipid level and liver index, and enhance glucose tolerance. The results of cell experiments showed that CPs could effectively reduce the accumulation of lipids in LO2 cells and inhibit the accumulation of reactive oxygen species (ROS). In addition, CPs could markedly reduce liver lipid accumulation in the liver cell and liver tissue, as further evidenced by the reduced expression of SREBP-1c in human non-tumour hepatic (LO2) cells. Meanwhile, the increased expression of SIRT1/PPAR-α and Nrf2/HO-1 pathways under the pretreatment of CPs in LO2 cells indicated that CPs could markedly relieve high fat-induced fatty liver injury, regulate insulin sensitivity, and reduce production of ROS. The results of in vivo and in vitro experiments demonstrated that CPs provided potential prevention and auxiliary treatment for NAFLD through reducing lipid accumulation, alleviating insulin resistance, and inhibiting oxidative stress. This study investigated the biological activity of CPs and laid the theoretical basis for the development of CP-based functional foods and dietary supplements.

Reducing synthetic colorants release from alginate-based liquid-core beads with a zein shell

An innovative method to reduce hydrophilic synthetic colorant release at interface was presented in this work, based on the anti-solvent effect at the membrane outside surface of liquid-core beads manufactured by reverse spherification between alginate and calcium ion. Zein, a hydrophobic protein which formed precipitation shell ensured the stability of colorant. Acidification of solvent made zein particles more kinetically stable, allowed zein stretching and collated more orderly secondary structures even in high polarity solvents. Colorants that hydrogen bonded or electrostatically interacted with zein could have optimized release properties. The zein/erythrosine samples had the most orderly secondary structure from circular dichroism and had the highest stability among all zein/colorant systems. The release rate of erythrosine was only 2.76% after 48 h storage after soaking in zein shell solution. This study demonstrated a promising clean and scalable strategy to encapsulate hydrophilic compounds in zein-based shells of liquid-core beads for food, supplement and pharmaceutical applications.

Nanoencapsulation of lutein within lipid-based delivery systems: Characterization and comparison of zein peptide stabilized nano-emulsion, solid lipid nanoparticle, and nano-structured lipid carrier

Three lipid-based carriers encapsulating lutein, nano-emulsion (NE), solid lipid nanoparticle (SLN), and nano-structured lipid carrier (NLC), were developed from zein peptides hydrolyzed by trypsin (TZP) and flavourzyme (FZP) as stabilizers. The physiochemical properties of FZP and TZP were evaluated. The particle size, potential, microstructure, environmental stability, rheological properties, in vitro digestion stability, and bioavailability of the lutein-loaded NE, SLN, and NLC were compared. The results showed that the surface hydrophobicity of TZP was higher than that of FZP. Except for the SLN, most samples were stable against droplet aggregation during storage, and carriers stabilized by TZP exhibited more favorable storage stabilities than those prepared from FZP. All the samples presented characteristics of fluid with good fluidity. The bioavailability of lutein was between 42.61% and 62.81%. In summary, these results provide valuable insights into the design of lipid-based delivery systems for fat-soluble biologically active compounds using zein peptides as stabilizers.

Effects of covalent modification with epigallocatechin-3-gallate on oleosin structure and ability to stabilize artificial oil body emulsions

The purpose of this study was to enhance the stability and functional properties of artificial oil body (AOB) emulsions. Herein, we covalently conjugated oleosin (OL) and epigallocatechin-3-gallate (EGCG) under alkaline conditions to obtain OL-EGCG conjugates. The results revealed that the structural characteristics of OL are improved by covalent binding to EGCG, with the OL-EGCG yield maximized at an EGCG concentration of 150 μM. We prepared AOB emulsions using native OL, the OL-EGCG conjugates, phosphatidylcholine (PC), and soybean oil for embedding curcumin. The results show that the protein components and phospholipids are bound in the AOB emulsion by hydrogen bonding and hydrophobic interactions. The covalent OL-EGCG/PC-stabilized emulsions exhibited more uniform droplet distributions, stronger thermal stabilities, and higher curcumin retentions than the other samples. These results indicated that the OL-EGCG/PC complexes are potential stabilizers for AOB emulsions and provided fresh insight into preparing highly stable emulsion embedding systems with good encapsulation efficiencies.