The pro-absorptive effect of glycosylated zein-fatty acid complexes on fucoxanthin via the lipid transporter protein delivery pathway

Growing research confirms that lipid transport proteins play a key role in the trans-intestinal epithelial transport of carotenoids. In this study, to simultaneously improve the digestive stability and intestinal absorption of fucoxanthin (FX), functionalized vectors with a capability of up-regulating the expression of FX-specific lipid transporter proteins was fabricated. The results showed that myristic acid, palmitic acid, and stearic acid effectively promoted FX-specific lipid transporter protein expression and formed stable self-assembly complexes with Millard-modified zein (MZ). The FX was sufficiently encapsulated in the MZ-fatty acid (FA) particles, forming spherical nanoparticles with a "core-shell" structure. Simulated gastrointestinal digestion showed that FA introduction significantly increased the FX bioaccessibility. In vivo results further verified that adding FAs dramatically increased the FX serum response concentration. These findings suggest that incorporating nutrients that can promote lipid transporter protein expression into delivery vehicles should be an effective strategy for improving oral carotenoid absorption.

Fabrication and characterization of alginate-zein core-shell microcapsules for controlled release of buckwheat honey

In this study, extrusion method was employed to fabricate alginate-zein core-shell microcapsules loaded with buckwheat honey by dropping alginate and buckwheat honey mixture solution into a 70.0 % zein ethanol solution(v/v) containing 5.0 % CaCl2 solution (wt%). The microcapsules were constructed by two parts: 1) the formation of hydrophilic beads through the crosslinking of alginate chains with Ca2+; 2) the introduction of alginate beads into the aqueous zein ethanol solution which decreased the ethanol concentration, prompting the precipitation of zein and the deposition of zein nanoparticles onto the surfaces of alginate beads. Comparing with the alginate beads, the prepared microcapsules not only possessed better water-holding capacity, but also achieved controlled release of buckwheat honey. Importantly, the microcapsules significantly retained the antioxidant activity of the buckwheat honey. Therefore, this innovative method for fabricating alginate-zein core-shell microcapsules can suggest a promising approach to broaden the application of buckwheat honey in the food field.

pH-induced interaction mechanism of zearalenone with zein: Binding characteristics, conformational structure and intermolecular forces

Zein-bound zearalenone (ZEN) complexes are naturally existed in maize by their spontaneous interaction, which significantly impacts the risk assessment of ZEN. Additionally, the pH levels in processing could affect the binding or release of zein-bound ZEN. In this study, pH-induced interaction mechanism of ZEN with zein were studied. Results showed that the acid conditions increased the binding constant (Ka) from 3.46 to 10.0 × 104 L/mol, binding energy from -17.38 to -43.49 kJ mol-1. By increasing hydrophobic interaction and hydrogen bond of ZEN with zein, the binding of ZEN with zein was promoted, forming zein-bound ZEN. Whereas, alkaline conditions decreased the Ka to 1.45 × 104 L/mol and binding energy to 148.48 kJ mol-1, weakened ZEN-zein interaction and stretched zein molecules, resulting the release of ZEN from zein. This study could provide important theoretical basis for perfecting risk assessment and controlling zein-bound ZEN during processing.

Resveratrol-loaded pH-responsive Mesona chinensis polysaccharides-zein nanoparticles for effective treatment of ulcerative colitis

BACKGROUND

Resveratrol (Res) is promising food functional factor with favorable antioxidant and anti-inflammatory properties, although its poor water solubility and low bioavailability limit extensive application. Therefore, in combination with another promising polysaccharide (Mesona chinensis polysaccharides, MCP), Res-loaded food nanocarriers (ResNPs) were developed to increase its water solubility, bioactivity and targeting properties. ResNPs were then applied to alleviate dextran sulfate sodium (DSS)-induced ulcerative colitis.

RESULTS

Resveratrol can be well encapsulated in MCP-based nanoparticles in an amorphous state, improving its water solubility. ResNPs showed pH-response controlled release behavior in the gastrointestinal tract and increased the enrichment of Res in the colon. In vivo experiments of ResNPs against DSS-induced ulcerative colitis (UC) revealed that ResNPs significantly improved UC symptoms, modulated intestinal inflammation and down-regulated oxidative stress levels compared to free Res. ResNPs also play an positive role with respect to inhibiting the mitogen-activated protein kinase pathway and promoting the expression of tight junction proteins. In addition, ResNPs improved the species composition and relative abundance of intestinal flora in UC mice, which effectively regulated the balance of intestinal flora and promoted the production of short-chain fatty acids.

CONCLUSION

These results suggest that MCP-based nanoparticles can effectively improve the solubility of resveratrol and enhance its in vivo bioactivity. Moreover, the present study also provides a new strategy for the prevention and treatment of UC with food polyphenol. © 2024 Society of Chemical Industry.

Metformin Loaded Zein Polymeric Nanoparticles to Augment Antitumor Activity against Ehrlich Carcinoma via Activation of AMPK Pathway: D-Optimal Design Optimization, In Vitro Characterization, and In Vivo Study

Metformin (MET), an antidiabetic drug, is emerging as a promising anticancer agent. This study was initiated to investigate the antitumor effects and potential molecular targets of MET in mice bearing solid Ehrlich carcinoma (SEC) as a model of breast cancer (BC) and to explore the potential of zein nanoparticles (ZNs) as a carrier for improving the anticancer effect of MET. ZNs were fabricated through ethanol injection followed by probe sonication method. The optimum ZN formulation (ZN8) was spherical and contained 5 mg zein and 30 mg sodium deoxycholate with a small particle size and high entrapment efficiency percentage and zeta potential. A stability study showed that ZN8 was stable for up to three months. In vitro release profiles proved the sustained effect of ZN8 compared to the MET solution. Treatment of SEC-bearing mice with ZN8 produced a more pronounced anticancer effect which was mediated by upregulation of P53 and miRNA-543 as well as downregulation of NF-κB and miRNA-191-5p gene expression. Furthermore, ZN8 produced a marked elevation in pAMPK and caspase-3 levels as well as a significant decrease in cyclin D1, COX-2, and PGE2 levels. The acquired findings verified the potency of MET-loaded ZNs as a treatment approach for BC.

Insights into the preparation of zein nanoparticles by continuous membrane nanoprecipitation

Nanoparticles (NPs) preparation is limited to an exclusive use in batch processes and small-scale formulations. The use of membranes as high-performance micromixers is expected to open new scenarios to overcome limitations of conventional nanoprecipitation system such as stirred tank (ST) nanoprecipitation. The ability of the porous membrane to add uniformly one phase to another and govern their mixing at the membrane interface seems to be an important parameter for obtaining uniform NPs. Inorganic membranes (pore size of 1 μm) were used to carry out membrane nanoprecipitation (MN) to form Zein nanoparticles (ZNPs) at pores level by non-solvent induced phase separation. A systematic study of the preparation of ZNPs in the ST and MN systems was carried out to establish the Ouzo diagram. The influence of zein concentration and solvent to non-solvent ratio on the size and size distribution of ZNPs was also investigated. A wider stable Ouzo zone was obtained with MN than with the ST process. ZNPs size increased from 100 nm up to 700 nm, while maintaining low polydispersity index (PDI < 0.2). The results demonstrate the suitability of MN for the continuous production of ZNPs and open the possibility of scaling up the nanoprecipitation process.

Co-delivery of siAEG-1 and doxorubicin to treat osteosarcoma via nanomicelles for azide-alkyne "click" conjugation of poly(l-lysine) dendrons onto Zein

Astrocyte elevated gene-1 (AEG-1) oncogene is a notorious and evolving target in a variety of human malignancies including osteosarcoma. The RNA interference (RNAi) has been clinically proven to effectively knock down specific genes. To successfully implement RNAi in vivo, protective vectors are required not only to protect unstable siRNAs from degradation, but also to deliver siRNAs to target cells with controlled release. Here, we synthesized a Zein-poly(l-lysine) dendrons non-viral modular system that enables efficient siRNA-targeted AEG-1 gene silencing in osteosarcoma and encapsulation of antitumor drugs for controlled release. The rational design of the ZDP integrates the non-ionic and low immunogenicity of Zein and the positive charge of the poly(l-lysine) dendrons (DPLL) to encapsulate siRNA and doxorubicin (DOX) payloads via electrostatic complexes and achieve pH-controlled release in a lysosomal acidic microenvironment. Nanocomplexes-directed delivery greatly improves siRNA stability, uptake, and AEG-1 sequence-specific knockdown in 143B cells, with transfection efficiencies comparable to those of commercial lipofectamine but with lower cytotoxicity. This AEG-1-focused RNAi therapy supplemented with chemotherapy inhibited, and was effective in inhibiting the growth in of osteosarcoma xenografts mouse models. The combination therapy is an alternative or combinatorial strategy that can produce durable inhibitory responses in osteosarcoma patients.

Biopolymer zein nanoparticles loaded with Moringa Oleifera extract for improved wound healing activity: Development, Qbd based optimization and in vivo study

Recently, nanobiomaterials have been explored for improved biological activities and value addition to the herbal extracts. Zein is a natural biopolymer with excellent pharmaceutical characteristics for topical applications. Moringa oleifera plant possesses large number of phytopharmaceuticals and its leaves are used in wound healing since ancient time. In this study, we studied first time, encapsulation of Moringa oleifera leaves aqueous extract into zein nanoparticles which are developed and optimized using quality by design approach. Moringa oleifera leaves aqueous extract was characterized by FTIR and total phenolic content determination. Moringa oleifera leaves aqueous extract loaded zein nanoparticles were systematically characterized for particle size, PDI, zeta potential, transmission electron microscopy and loading capacity. Further, a gel having optimized formulation for topical application was prepared and characterized for pH, spreadability, extrudability and storage stability. The so developed formulation were tested for wound healing activities on animals and results clearly indicated significant activity (p < 0.05) in case of Moringa oleifera leaves aqueous extract loaded zein nanoparticles formulation than control and relatively improved wound healing than Moringa oleifera leaves aqueous extract only loaded gel . This study opens up new possibilities in exploring zein nanoparticles for herbal extract based therapeutic applications.

Pickering emulsion templated proteinaceous microparticles as glutathione-responsive carriers for endocytosis in tumor cells

The use of glucose oxidase (GOx) to disrupt glucose supply has been identified as a promising strategy in cancer starvation therapy. However, independent delivery of GOx is prone to degradation upon exposure to biological conditions and may cause damage to blood vessels and normal organs during transportation. Although some carriers can protect GOx from the surrounding environment, the harsh preparation conditions may compromise its activity. Moreover, the commonly used materials often exhibit poor biocompatibility and possess certain cytotoxicity. To address this issue, we developed a gentle and efficient method based on Pickering emulsion templates to synthesize protein-based microparticles using zein as the matrix material. These microparticles have high stability and can be tailored to efficiently encapsulate biomolecules while preserving their activity. Moreover, the zein-based microparticles can be triggered to release biomolecules in tumor cells under high glutathione levels, demonstrating excellent responsiveness, biocompatibility, and low cytotoxicity. Additionally, when loaded with GOx, these protein-based microparticles effectively deprive tumor cells of nutrients and induce apoptosis by generating high levels of H2O2, thereby exhibiting enhanced anticancer properties.

Preparation and characterization of chitosan/dialdehyde carboxymethyl cellulose composite film loaded with cinnamaldehyde@zein nanoparticles for active food packaging

In this study, zein-loaded cinnamaldehyde (Cin@ZN) nanoparticles were incorporated into Chitosan (CS)/dialdehyde carboxymethyl cellulose (DCMC) matrix to fabricate the active food packaging materials possessing outstanding antioxidant and antibacterial properties. The research investigated how varying levels of Cin@ZN nanoparticles affected the morphology, microstructure, physicochemical properties of CS/DCMC composite films. The inclusion of Cin@ZN could significantly improve the mechanical strength, reduce the water vapor and oxygen permeability of CS/DCMC composite films and endow films with UV-light blocking properties. It's worth noting that the antibacterial and antioxidant capacities of CS/DCMC films had an astonishing enhancement with Cin@ZN blending, in which ABTS scavenging ratio of the composite films (100 mg) with different Cin@ZN contents reached >90 %. Furthermore, CS/DCMC/Cin@ZN 35 % composite film has the ability to efficiently protect strawberries from microbial damage and decelerate the spoilage rate of strawberries under ambient condition. Consequently, the CS/DCMC/Cin@ZN composite film can be applied as packaging material to extend the lifespan of fruits.

Electrospun nanofibers based on zein and red onion bulb extract (Allium cepa, L.): Volatile compounds, hydrophilicity, and antioxidant activity

Onion is rich in bioactive and volatile compounds with antioxidant activity. However, the pungent odor of volatile compounds (VOCs) released restricts its use. The encapsulation of red onion extract by electrospinning is an alternative to mask this odor and protect its bioactive compounds. The main objective of this study was to encapsulate red onion bulb extract (ROE) in different concentrations into zein nanofibers by electrospinning and evaluate their thermal, antioxidant, and hydrophilicity properties. The major VOC in ROE was 3(2H)-furanone, 2-hexyl-5-methyl. Incorporating ROE into the polymeric solutions increased electrical conductivity and decreased apparent viscosity, rendering nanofibers with a lower average diameter. The loading capacity of ROE on fibers was high, reaching 91.5% (10% ROE). The morphology of the nanofibers was random and continuous; however, it showed beads at the highest ROE concentration (40%). The addition of ROE to the nanofibers increased their hydrophilicity. The nanofibers' antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl, nitric oxide, and hydroxyl radicals ranged from 32.5% to 57.3%. The electrospun nanofibers have the potential to protect and mask VOCs. In addition, they offer a sustainable alternative to the synthetic antioxidants commonly employed in the food and packaging industry due to their antioxidant activities.

Zein and hydroxypropyl methylcellulose acetate succinate microfibers combined with metronidazole benzoate and/or metronidazole-incorporated cellulose nanofibrils for potential periodontal treatment

The development of flexible and porous materials to control antibacterial delivery is a pivotal endeavor in medical science. In this study, we aimed to produce long and defect-free fibers made of zein and hydroxypropyl methylcellulose acetate succinate (HPMCAS) to be used as a platform for the release of metronidazole (MDZ) and metronidazole benzoate (BMDZ) to be potentially used in periodontal treatment. Microfibers prepared via electrospinning under a 2:3 (w/w) zein to HPMCAS ratio, containing 0.5 % (w/w) poly(ethylene oxide) (PEO) and 1 % (w/w) cellulose nanofibril (CNF) were loaded with 40 % (w/w) MDZ, 40 % (w/w) BMDZ, or a combination of 20 % (w/w) of each drug. The addition of CNF improved the electrospinning process, resulting in long fibers with reduced MDZ and BMDZ surface crystallization. MDZ- and BMDZ-incorporated fibers were semicrystalline and displayed commendable compatibility among drugs, nanocellulose and polymeric chains. Release tests showed that zein/HPMCAS/PEO fibers without CNF and with 20 % (w/w) MDZ/ 20 % (w/w) BMDZ released the drug at a slower and more sustained rate compared to other samples over extended periods (up to 5 days), which is a favorable aspect concerning periodontitis treatment.

Lactobacillus reuteri biofilms formed on porous zein/cellulose scaffolds: Synbiotics to regulate intestinal microbiota

Supplementing probiotics or indigestible carbohydrates is a usual strategy to prevent or revert unhealthy states of the gut by reshaping gut microbiota. One criterion that probiotics are efficacious is the capacity to survive in the gastrointestinal tract. Biofilm is the common growth mode of microorganisms with high tolerances toward harsh environments. Suitable scaffolds are crucial for successful biofilm culture and large-scale production of biofilm-phenotype probiotics. However, the role of scaffolds containing indigestible carbohydrates in biofilm formation has not been studied. In this study, porous zein/cellulose composite scaffolds provided nitrogen sources and carbon sources simultaneously at the solid/liquid interfaces, being beneficial to the biofilm formation of Lactobacillus reuteri. The biofilms showed 2.1-17.4 times higher tolerances in different gastrointestinal conditions. In human fecal fermentation, the biofilms combined with the zein/cellulose composite scaffolds act as the "synbiotics" positively modulating the gut microbiota and the short-chain fatty acids (SCFAs), where biofilms provide probiotics and scaffolds provide prebiotics. The "synbiotics" show a more positive regulation ability than planktonic L. reuteri, presenting potential applications in gut health interventions. These results provide an understanding of the synergistic effects of biofilm-phenotype probiotics and indigestible carbohydrates contained in the "synbiotics" in gut microbiota modulation.

Electrolyte-induced aggregation of zein protein nanoparticles in aqueous dispersions

Ion specific effects on the charging and aggregation features of zein nanoparticles (ZNP) were studied in aqueous suspensions by electrophoretic and time-resolved dynamic light scattering techniques. The influence of mono- and multivalent counterions on the colloidal stability was investigated for positively and negatively charged particles at pH values below and above the isoelectric point, respectively. The sequence of the destabilization power of monovalent salts followed the prediction of the indirect Hofmeister series for positively charged particles, while the direct Hofmeister series for negatively charged ones assumed a hydrophobic character for their surface. The multivalent ions destabilized the oppositely charged ZNPs more effectively and the aggregation process followed the Schulze-Hardy rule. For some multivalent ions, strong adsorption led to charge reversal resulting in restabilization of the suspensions. The experimental critical coagulation concentrations (CCCs) could be well-predicted with the theory developed by Derjaguin, Landau, Verwey and Overbeek indicating that the aggregation processes were mainly driven by electrical double layer repulsion and van der Waals attraction. The ion specific dependence of the CCCs is owing to the modification of the surface charge through ion adsorption at different extents. These results are crucial for drug delivery applications, where inorganic electrolytes are present in ZNP samples.

Enhanced mechanical properties and antibacterial activities of chitosan films through incorporating zein-gallic acid conjugate stabilized cinnamon essential oil Pickering emulsion

In this study, zein-gallic acid covalent complex prepared by alkali treatment was utilized as an emulsifier to stabilize cinnamon essential oil (CEO) Pickering emulsion, and the chitosan-based (CZGE) films loaded with CEO Pickering emulsion were prepared by blending. The influences of different contents of CEO Pickering emulsion on the physical properties and biological activities of CZGE films were investigated. The results showed that Pickering emulsion had good compatibility with chitosan matrix and enhanced the interaction between film-forming matrix polymer. In addition, incorporating with CEO Pickering emulsion (15 %, v/v) significantly improved the mechanical and barrier properties of the films, and also enhanced the light transmittance and thermal stability of the films. Furthermore, the loading of emulsion also improved the antioxidant activities of the films and led to the formation of high antimicrobial property against food pathogens, and the slow-release behavior of CEO could effectively extend the biological activity of the films. These results suggested that Pickering emulsion has potential as a loading system and a plasticizer in active packaging, and the feasibility of CZGE film in food packaging.

Antimicrobial and antioxidant activity of encapsulated tea polyphenols in chitosan/alginate-coated zein nanoparticles: a possible supplement against fish pathogens in aquaculture

Regulation of antibiotic use in aquaculture calls for the emergence of more sustainable alternative treatments. Tea polyphenols (GTE), particularly epigallocatechin gallate (EGCG), have various biological activities. However, tea polyphenols are susceptible to degradation. In this work, EGCG and GTE were encapsulated in zein nanoparticles (ZNP) stabilized with alginate (ALG) and chitosan (CS) to reduce the degradation effect. ALG-coated ZNP and ALG/CS-coated ZNP encapsulating EGCG or GTE were obtained with a hydrodynamic size of less than 300 nm, an absolute ζ-potential value >30 mV, and an encapsulation efficiency greater than 75%. The antioxidant capacity of the encapsulated substances, although lower than that of the free ones, maintained high levels. On the other hand, the evaluation of antimicrobial activity showed greater efficiency in terms of growth inhibition for ALG/CS-ZNP formulations, with average overall values of around 60%, reaching an inhibition of more than 90% for Photobacterium damselae. These results support encapsulation as a good strategy for tea polyphenols, as it allows maintaining significant levels of antioxidant activity and increasing the potential for antimicrobial activity, in addition to increasing protection against sources of degradation.

Carotenoid degradation rate in milled grain of dent maize hybrids and its relationship with the grain physicochemical properties

Carotenoids in maize grain degrade during storage, but the relationship between their stability and the physicochemical properties of the grain is unclear. Therefore, the carotenoid degradation rate in milled grain of three dent hybrids differing in grain hardness was evaluated at various temperatures (-20, 4 and 22 °C). The carotenoid degradation rate was calculated using first-order kinetics based on the content in the samples after 7, 14, 21, 28, 42, 56, 70 and 90 days of storage and related to the physicochemical properties of the grain. The highest grain hardness was found in the hybrid with the highest zein and endosperm lipid concentration, while the lowest grain hardness was found in the hybrid with the highest amylose content and the specific surface area of starch granule (SSA). As expected, carotenoids in milled maize grain were most stable at -20 °C, followed by storage at 4 and 22 °C. Tested hybrids differed in the degradation rate of zeaxanthin, α-cryptoxanthin and β-carotene, and these responses were also temperature-dependent. In contrast, all hybrids showed similar degradation rate for lutein and β-cryptoxanthin regardless of the storage temperature. Averaged over the hybrids, the degradation rate for individual carotenoids ranked as follows: lutein < zeaxanthin < α-cryptoxanthin < β-cryptoxanthin < β-carotene. The lower degradation rate for most carotenoids was mainly associated with a higher content of zein and specific endosperm lipids, with the exception of zeaxanthin, which showed an opposite pattern of response. Degradation rate for lutein and zeaxanthin negatively correlated with SSA, but interestingly, small starch granules were positively associated with higher degradation rate for mostcarotenoids. Dent-type hybrids may differ significantly in carotenoid degradation rate, which was associated with specific physicochemical properties of the maize grain.

The role of polysaccharides in improving the functionality of zein coated nanocarriers: Implications for colloidal stability under environmental stresses

Zein has gained popularity over the past few years as an incredible food and bio-based materials. The potential functions and health benefits of zein microcapsules or micro-/nanoparticles in bioactive components delivery, structured emulsion, etc., have received great attention. However, the development has been limited by colloidal destabilization, especially when thermal processing is involved. There is a recent trend in developing zein-polysaccharide complexes (ZPCs), which has tremendously improved the performance of zein-based colloidal carrier systems or emulsions. Increasing our understanding of zein interactions and their contribution to the structure of various macromolecules can help us to develop novel biomaterials that can be used in food, agriculture, biomedicine, and cosmetics. In addition, these nanocarriers are suitable for the encapsulation and delivery of bioactive compounds which have positive perspective in food industry. Therefore, this article aimed to review recent advances in the ZPCs that can be applied to functional or health-promoting foods, with a focus on the characteristics of different ZPCs, factors and mechanisms affecting the stability (especially thermal stability) of these complexes, and their application in food industry as a carrier for BCs. Further, the stability of ZPCs based emulsions under processing and physiological environments, as well some typical effective methods are introduced. Also, the principal challenges and prospects were enumerated and discussed.

Prodigiosin/celecoxib-loaded into zein/sodium caseinate nanoparticles as a potential therapy for triple negative breast cancer

Nowadays, breast cancer is considered one of the most upsetting malignancies among females. Encapsulation of celecoxib (CXB) and prodigiosin (PDG) into zein/sodium caseinate nanoparticles (NPs) produce homogenous and spherical nanoparticles with good encapsulation efficiencies (EE %) and bioavailability. In vitro cytotoxicity study conducted on human breast cancer MDA-MB-231 cell lines revealed that there was a significant decline in the IC50 for encapsulated drugs when compared to each drug alone or their free combination. In addition, results demonstrated that there is a synergism between CXB and PDG as their combination indices were 0.62251 and 0.15493, respectively. Moreover, results of scratch wound healing assay revealed enhanced antimigratory effect of free drugs and fabricated NPs in comparison to untreated cells. Furthermore, In vitro results manifested that formulated nanoparticles exhibited induction of apoptosis associated with reduced angiogenesis, proliferation, and inflammation. In conclusion, nanoencapsulation of multiple drugs into nanoparticles might be a promising approach to develop new therapies for the managing of triple negative breast cancer.

An innovative solid-phase biosensor for rapid on-site detection of N-nitrosodimethylamine incorporating zein film and upconversion nanoparticles

Pickled frequently contains nitrosodimethylamine (NDMA), a mutagenic and carcinogenic substance that is dangerous for the general public's health. This study reports on the fabrication of a fluorescent biosensor using zein film and aptamer functionalized upconversion nanoparticles (UCNPs) for on-site monitoring of NDMA in meat. UCNPs were first prepared followed by aptamer binding and mixing with zein film, which was further conjugated with cDNA of dabcyl modified at 5'. The fluorescence resonance energy transfer (FRET) mechanism between the UCNPs and dabcyl was exploited. The fluorescence signals of the zein film recovered when NDMA was present because it was selectively collected by the particular aptamer and damaged the cDNA structure. The designed functionalized zein film was used for on-site and portable determination of NDMA with a lower limit of detection of 0.017 ng/mL, and possessed a satisfactory recovery ranging from 95.8% to 100.2% with no significant difference compared with the GC-MS method.

Emulsion electrospinning of zein nanofibers with carotenoid microemulsion: Optimization, characterization and fortification

In this study, carotenoid microemulsion was encapsulated in zein nanofibers via emulsion electrospinning. Optimization study was applied to determine optimum parameters by response surface methodology. The voltage, flow rate and distance as optimum conditions were determined as 23 kV, 1.7 mL/h and 12.75 cm, respectively. Lycopene, β-carotene, encapsulation efficiency, encapsulation yield and zeta potential of zein nanofibers in optimum conditions were estimated as 4.054 mg/kg, 0.649 mg/kg, 77.78%, 41.76% and -29.73 mV, respectively. The addition of microemulsion affected nanofibers diameter and morphologies. Diffusion coefficient of zein nanofibers decreased with addition of microemulsion under optimum conditions. The electrospinning improved thermal stability of microemulsion. The carotenoid microemulsion could be entrapped into the zein fibers according to ATR-FTIR spectrum. Model foods were fortificated with zein nanofibers. The addition of nanofibers changed color of the foods during the storage. Carotenoid compounds were more stable in nanofibers followed by olive oil, milk and water.

Formulation of Chitosan-Zein Nano-in-Microparticles for Oral DNA Delivery

Gene delivery via the oral route offers a promising strategy for improving DNA vaccination and gene-based therapy outcomes. The noninvasive nature of oral delivery lends to ease of dosing, which can facilitate convenience and patient compliance. Moreover, oral administration allows for both local and systemic production of therapeutic genes or, in the case of DNA vaccination, mucosal and systemic immunity. Here, we describe the methods to produce a dual biomaterial, oral DNA delivery system composed of chitosan (CS) and zein (ZN). In this system, CS serves to encapsulate and deliver DNA cargo to intestinal cells in the form of CS-DNA nanoparticles (CS-DNA NPs), while ZN is used to form a protective matrix around the CS-DNA NPs that prevent degradation during gastric transit but then degrades to release the CS-DNA NPs for transfection upon entry into the intestines. These particles have demonstrated the ability to effectively protect cargo DNA from simulated gastric degradation in vitro and mediate transgene production in vivo, making them an effective oral gene delivery system.

Substantial and efficient adsorption of heavy metal ions based on protein and polyvinyl alcohol nanofibers by electrospinning

The adverse effects of heavy metal pollutants in wastewater have threatened human health in recent decades. Therefore, the development of absorbents for such pollutants is essential to overcome these problems. Electrospun nanofibers are often used for wastewater treatment owing to their high porosity and high specific surface area. Zein from plants and collagen from animals are vulnerable to moisture, which limits its broad application in practice. However fully biodegradable polyvinyl alcohol (PVA), which is soluble in water, can be mixed with protein individually to overcome the limitation. In this work, the two proteins described above and PVA were combined to prepare protein nanofibers by electrospinning technology, which could achieve adsorption of Cu2+. As the protein content increased, the adsorption properties of the obtained nanofibers for Cu2+ showed a rising and then decreasing trend, with the highest point at 50 % of protein content, especially the collagen nanofibers, which reached 24.62 mg/g. Both protein nanofibers reached adsorption equilibrium after 15 h, but overall, collagen nanofibers showed a superior adsorption performance for Cu2+ than that by zein nanofibers. In the process of Cu2+ adsorption by protein nanofibers, both physical and chemical effect existed, and the physical effect played the leading role.

Improved antioxidant activity and delivery of peppermint oil Pickering emulsion stabilized by resveratrol-grafted zein covalent conjugate/quaternary ammonium chitosan nanoparticles

Novel nanoparticles (Z-R/H) were successfully fabricated by a resveratrol-grafted zein covalent conjugate (Z-R) combined with quaternary ammonium chitosan (HTCC), which were used as stabilizers to prepare peppermint oil (PO) Pickering emulsions with antioxidant activity. HTCC effectively adjusted wettability of Z-R conjugate, and three-phase contact angle of Z-R/H3:1 was moderate (95.01°). The influencing factors of Pickering emulsion formation, including volume fraction of PO, concentration of Z-R/H, and mass ratio of Z-R to HTCC, were evaluated by droplet size, ζ-potential, microscopic observation, and stability index analysis. Pickering emulsions stabilized by Z-R/H3:1 showed excellent physical stability under heat treatment. Z-R/H nanoparticles adsorbed on the oil-water interface yielded a dense filling layer as a physical barrier to improve the emulsion stability, which was validated by confocal laser-scanning microscopy. After 4 weeks of storage, retention rate of PO in Pickering emulsion stabilized by Z-R/H3:1 remained high (72.1 %). Electronic nose analysis showed that Z-R/H3:1-stabilized emulsion effectively prevented volatilization of PO aroma components. Additionally, PO and Z-R/H nanoparticles provided an additive antioxidant effect of Pickering emulsions against DPPH and ABTS free radicals. In summary, these novel Z-R/H nanoparticle offer promising applications as a stabilizer with great potential in preparing functional Pickering emulsions to improve essential oil delivery.

The improved bioavailability of zein/soybean protein isolate by puerarin in vitro

As the largest emitter of greenhouse gases, the livestock and poultry industry is facing the challenge of increasing production to meet global demand while reducing environmental impacts. Improving feed digestibility by optimizing feed structure (e.g., exogenous additive) is one of the green breeding measures to alleviate carbon pressure. In this study, the interaction mechanism and in vitro digestibility properties of puerarin (PUE) with feed proteins (zein and soy protein isolate (SPI)) to form Zein-PUE and SPI-PUE complexes were investigated mainly by multispectral and molecular docking techniques. Results indicated that the addition of PUE improved the physicochemical properties of proteins (e.g., solubility and disulfide bond contents). Then, the spectral results showed that the binding processes were spontaneous, and the protein structure tended to loose and disordered after binding, and more hydrophobic residues were exposed to the hydrophilic microenvironment. Moreover, on the basis of molecular docking revealed that PUE bound to zein by hydrogen bond, electrostatic and hydrophobic interactions, while with SPI by hydrogen bond and hydrophobic interaction. Finally, in vitro digestion experiments demonstrated that the bioavailability of Zein-PUE and SPI-PUE complexes increased by 1.15 % and 2.11 %, respectively. Overall, PUE is a promising feed additive beneficial for enhancing protein digestibility and bioavailability.

Emerging Zein-Bound Zearalenone in Maize: Thermal-Induced Mechanism of Binding or Releasing

The emerging zein-bound zearalenone (ZEN) in maize could affect its nutrition and health. Besides, thermal processing could affect the zein-ZEN interaction, causing the binding or release of ZEN. To control the harm of zein-bound ZEN on the quality of maize, the thermal-induced mechanism of binding or releasing of zein-bound ZEN were studied. Results showed that thermal processing decreased the binding constant from 1.70 to 0.27 × 104 L mol-1, and binding energy from -78.41 to -32.51 kJ mol-1, with the decreased hydrogen bonds, hydrophobic, and electrostatic interactions of ZEN with Leu81 and Arg85, Val125, Ala129, and Gln132. Furthermore, thermal processing destroyed the interactions among zein molecules and caused the unwinding of zein, releasing the ZEN from the hydrophobic cavity of zein. This paper provided theoretic insights into the heat-induced binding/releasing mechanism of ZEN with zein, which helped to perfect the exposure risk evaluation of ZEN (including free and zein-bound ZEN) in maize-based products.

Food packaging films based on ionically crosslinked konjac glucomannan incorporating zein-pectin nanoparticle-stabilized corn germ oil-oregano oil Pickering emulsion

This study addresses the limitations of konjac glucomannan (KGM) films in mechanical properties, hydrophobicity and antibacterial activities. For the first time, a zein-pectin nanoparticle-stabilized corn germ oil-oregano essential oil Pickering emulsion (ZPCEO) was incorporated into KGM, with the resulting film being further ionically crosslinked with Ca2+, Cu2+ or Fe3+. FTIR, SEM and EDS results showed that the metal ions were crosslinked with the hydroxyl and carbonyl groups of polysaccharides and uniformly distributed throughout the films (degree of crosslinking: Fe3+ > Cu2+ > Ca2+). Compared with pure KGM films, the ionic crosslinked ZPCEO/KGM (IL-ZPCEO/KGM) films have superior water resistance mechanical properties, and exhibit unique UV-blocking properties, antioxidant and antibacterial activities. The ZPCEO/KGM-Fe3+ film offered the best all-round properties, including the highest tensile strength, water resistance, UV-blocking capacity, and antimicrobial activity. Thus, ionic crosslinking of ZPCEO/KGM films can be applied to the preparation of food packaging for use in high humidity environments.

Label-free electrochemical immunosensor for detection of insulin-like growth factor-1 (IGF-1) using a specific monoclonal receptor on electrospun Zein-based nanofibers/rGO-modified electrode

A novel electrochemical immunosensor was developed for ultrasensitive determination of the hormone insulin-like growth factor 1 (IGF-1) based on immobilization of a specific monoclonal antibody on the electrospun nanofibers of Polyacrylonitrile (PAN)/Zein-reduced graphene oxide (rGO) nanoparticle. The nanofibers deposited on glassy carbon electrode (GCE) showed good electrochemical behaviors with synergistic effects between PAN, Zein, and rGO. PAN/Zein nanofibers were used due to flexibility, high porosity, good mechanical strength, high specific surface area, and flexible structures, while rGO nanoparticles were used to improve the detection sensitivity and anti-IGF-1 immobilizing. Different characterization techniques were applied consisting of FE-SEM, FT-IR, and EDS for the investigation of morphological features and nanofiber size. The redox reactions of [Fe(CN)6]4-/3- on the modified electrode surface were probed for studying the immobilization and determination processes, using differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Under optimal conditions, LOD (limit of detection) and LOQ (limit of quantification) were obtained as 55.72 fg/mL and 185.73 fg/mL respectively, and sensitivity was acquired 136.29 μA/cm2.dec. Moreover, a wide linear range was obtained ranging from 1 pg/mL to 10 ng/mL for IGF-1. Furthermore, the proposed method was applied for the analysis of IGF-1 in several human plasma samples with acceptable results, and it also exhibited high selectivity, stability, and reproducibility.

Fabrication and optimization of itraconazole-loaded zein-based nanoparticles in coated capsules as a promising colon-targeting approach pursuing opportunistic fungal infections

Itraconazole (ITZ), a broad-spectrum antifungal drug, was formulated into colon-targeting system aiming to treat opportunistic colonic fungal infections that commonly infect chronic inflammatory bowel diseases (IBD) patients due to immunosuppressive therapy. Antisolvent precipitation technique was employed to formulate ITZ-loaded zein nanoparticles (ITZ-ZNPs) using various zein: drug and aqueous:organic phase ratios. Central composite face-centered design (CCFD) was used for statistical analysis and optimization. The optimized formulation was composed of 5.5:1 zein:drug ratio and 9.5:1 aqueous:organic phase ratio with its observed particle size, polydispersity index, zeta potential, and entrapment efficiency of 208 ± 4.29 nm, 0.35 ± 0.04, 35.7 ± 1.65 mV, and 66.78 ± 3.89%, respectively. ITZ-ZNPs were imaged by TEM that revealed spherical core-shell structure, and DSC proved ITZ transformation from crystalline to amorphous form. FT-IR showed coupling of zein NH group with ITZ carbonyl group without affecting ITZ antifungal activity as confirmed by antifungal activity test that showed enhanced activity of ITZ-ZNPs over the pure drug. Histopathological examination and cytotoxicity tests ensured biosafety and tolerance of ITZ-ZNPs to the colon tissue. The optimized formulation was then loaded into Eudragit S100-coated capsules and both in vitro release and in vivo X-ray imaging confirmed the success of such coated capsules in protecting ITZ from the release in stomach and intestine while targeting ITZ to the colon. The study proved that ITZ-ZNPs is promising and safe nanoparticulate system that can protect ITZ throughout the GIT and targeting its release to the colon with effectual focused local action for the treatment of colon fungal infections.

One Platform Comparison of Polymeric and Lipidic Nanoparticles for the Delivery of Amphotericin B

Amphotericin B (AmB) is a membrane-acting antibiotic used for the treatment of fungal and protozoal infections. AmB exists in various molecular forms, i.e., monomeric, super-aggregated, and oligomeric forms, where oligomeric forms are highly toxic because of their relative affinity toward cholesterol present over human cell membrane. Hence, the objective of our research work was to study the aggregation state of AmB in two different nanoformulations, i.e., solid lipid nanoparticles (SLNs) and zein-based nanoparticles (PNPs), with the aim of enhancing the fraction of less toxic form of AmB, and a comparative study was performed. The zein and glyceryl monostearate can intercalate the polyenic domain of AmB and thereby hinder the hydrophobic attractions between the AmB molecules, which allows their existence in monomeric forms. The particle size of AmB-SLNs and AmB-PNPs were 378.90 ± 9.50 nm and 184.90 ± 6.00 nm, while zeta potential was -34.97 ± 0.51 mV and +28.93 ± 2.29 mV, respectively. In vitro release studies showed more controlled release of AmB from PNPs (52.48 ± 1.07%) as compared to SLNs (86.33 ± 0.93%). The predominant aggregation state of AmB in both formulations was determined by UV-visible and circular dichroism spectrophotometry, where a higher degree of monomerization of AmB was reported in AmB-SLNs as compared to AmB-PNPs. Toxicity of the nanoformulations was evaluated through hemolysis test, where the results suggested that AmB-SLNs and AmB-PNPs were less hemolytic as compared to pure AmB. The nanoformulations demonstrated the predominant monomeric form of AmB, which may offer higher selectivity index toward microbial membrane.

Zein nanoparticles as oral carrier for mometasone furoate delivery

Mometasone furoate (MF) is a synthetic glucocorticoid used clinically to treat specific inflammatory disorders including superior and inferior respiratory tract. Due to its poor bioavailability we further investigated whether nanoparticles (NPs) made of zein protein may constitute a safe and effective choice to incorporate MF. Thus, in this work, we loaded MF into zein NPs aiming to evaluate possible advantages that could result from oral delivery and extend the range of MF application such as inflammatory gut diseases. MF-loaded zein NPs presented an average size in the range of 100 and 135 nm, narrow size distribution (polydispersity index < 0.300), zeta potential of around + 10 mV and association efficiency of MF over 70%. Transmission electron microscopy imaging revealed that NPs had a round shape and presented a smooth surface. The zein NPs showed low MF release in a buffer that mimics the gastric condition (pH = 1.2) and slower and controlled MF release in the intestinal condition (pH = 6.8). The short and intermediate safety of zein NPs was confirmed assessing the incubation against Caco-2 and HT29-MTX intestinal cells up to 24 h. Permeability studies of MF across Caco-2/HT29-MTX co-culture monolayer evidenced that zein NPs modulated MF transport across cell monolayer resulting in a stronger and prolonged interaction with mucus, potentially extending the time of absorption and overall local and systemic bioavailability. Overall, zein NPs showed to be suitable to carry MF to the intestine and future studies can be developed to investigate the use of MF-loaded zein NPs to treat intestinal inflammatory diseases.

pH-responsive double-layer film based on chitosan/curcumin-β-cyclodextrin complex/cinnamaldehyde and zein/alizarin for pork freshness monitoring and maintaining

A pH-responsive double-layer film comprising chitosan (CS), zein (Z), curcumin-β-cyclodextrin complex (Cur- β-CD), alizarin (AL) and cinnamaldehyde (CIN) was developed to detect spoilage and prolong the shelf life of pork. The outer Z/AL is the colorimetric responsive and highly protective outer layer, while the CS/Cur- β-CD/CIN is the fluorescence responsive and functional layer. The CS/Cur- β-CD/CIN-Z/AL film demonstrated excellent barrier properties against oxygen (8.48 × 10-13 g (m s Pa)-1) and water (2.42 × 10-11 g (m s Pa)-1) primarily due to the polar interactions in the Z structure and its hydrophobic nature. The addition of AL and Cur provided the CS/Cur- β-CD/CIN-Z/AL film with pH colorimetric and fluorescence response capabilities, respectively. Furthermore, the inclusion of Cur- β-CD, CIN and AL significantly enhanced the film's antioxidant and antibacterial properties, with radical scavenging rates of 79.29 % (DPPH) and 89.84 % (ABTS), as well as antibacterial efficiencies of 96.2 % (S. aureus) and 85.78 % (E. coli). To test the effectiveness of the double-layer film, a freshness monitoring and maintenance experiment was conducted on pork stored at 4 °C for 8 days. Various parameters of pork, including surface color, pH value, total volatile bases nitrogen (TVB-N), total viable counts (TVC), thiobarbituric acid reactive substance (TBARS), hardness and springiness, were measured, along with the color and fluorescence intensity (FL) of the film. The shelf life of the pork was extended by at least 2 days compared to the control group, and the pork was considered inedible if ΔE ≥ 12 or FL intensity ≤ 2160. Overall, this food packaging film shows promise in simultaneously monitoring and maintaining the freshness of pork.

Color behavior of composite resin enhanced with different shapes of new antimicrobial polymer coated nanoparticles

BACKGROUND

Zein-coated magnesium oxide nanoparticles (zMgO NPs) demonstrate a potent antimicrobial effect, endorsing it as a compelling additive to dental materials formulations for oral health care advances. However, currently there is no data on the imprint of zMgO NPs on the color permanence of dental composites. The objective of this study is to evaluate the color stability of different types of composite enhanced with antimicrobial zein-coated magnesium oxide nanoparticles (zMgO NPs) of different shapes before and after thermocycling.

METHODS

Two hundred composite samples were divided into four groups: Gp1: Tetric N-Flow with zMgO nanowires, Gp2: Tetric N-Flow with zMgO nanospheres, Gp3: Tetric N-Ceram with zMgO nanowires; Gp4: Tetric N-Ceram with zMgO nanospheres. Each group was subdivided into 5 subgroups (n = 10) with concentrations of zMgO NPs 0%, 0.3%, 0.5%, 1% and 2%. The characterization of the modified composite containing the zMgO was done via X-ray Diffraction, Field Emission Scanning Electron Microscopy (FESEM), and Fourier Transform Infrared Spectroscopy (FTIR). Colorimetric evaluation was performed through spectrophotometry with a white background. Samples underwent color assessment using a spectrophotometer, followed by thermocycling, and then another color assessment.

RESULTS

FESEM analysis showed a uniform distribution of the zMgO nanoparticles in the composite and FTIR illustrated no change in the spectra. However, the XRD spectra exhibited an amorphous pattern in the composite enhanced with zMgO NPs. There was no compelling discrepancy in color variation ΔE among the different groups before and after thermocycling (p > 0.05). A statistically notable variation in ΔL was found amid the control and N-Flow and N-Ceram with 2% zMgO nanospheres before and after thermocycling respectively (p < 0.05). While after thermocycling, there was a statistically significant difference in Δa in N-Flow and N-Ceram wires amid the control and the different groups (p < 0.05). Additionally, after thermocycling there was a statistically significant difference in Δb in N-Flow and N-Ceram wires between the control and the different groups (p < 0.05). The Tukey test exhibited no variation among the groups with different zMgO concentrations (p > 0.05).

CONCLUSION

Enhancing N-Flow and N-Ceram composite with antimicrobial zMgO nanowires and nanospheres did not alter the total color stability of the materials before and after thermocycling.

Synergetic-effect-enhanced electrochemiluminescence of zein-protected Au-Ag bimetallic nanoclusters for CA15-3 detection

In this work, a sandwich-type electrochemiluminescence (ECL) system was constructed for the detection of CA15-3. Gold-silver bimetallic nanoclusters (Au-Ag BNCs) with zein as a protective ligand were synthesized, and the excellent ECL performance of this material was demonstrated for the first time. Zein carrying a variety of groups that ligated with Au-Ag BNCs, forming a protective shell of zein, effectively prevented clusters from aggregating or growing into larger nanoparticles. The synergistic effect of the bimetal promotes the ECL emission, making this nanoscale material an ideal ECL probe. GO-PANI, which effectively promoting the production of sulfate radicals of the co-reactant and significantly increasing the ECL strength, was a good sensing platform for antibody immobilization. Consequently, we constructed an ECL sensor with GO-PANI as the sensing platform and Au-Ag BNCs@zein as the ECL probe, with a detection range of 0.001-100 U mL-1 and a detection limit of 0.0003 U mL-1, provided a strong support for the sensor for future CA15-3 detection applications.

Design and evaluation of propranolol hydrochloride loaded thiolated Zein/PEO electrospun fibrous matrix for transmucosal drug delivery

Thiolated polymers have garnered wide attention from researchers on mucoadhesive drug delivery. This work explores the thiolation of zein protein using cysteine amino acid via the EDC crosslinker. The optimization of thiolation and purification have been done and confirmed using Ellman's assay and Raman spectra. The thiolated Zein/PEO polymer blend has been appraised for electrospinning to fabricate fibrous matrices. The extent of thiol modification augmented the mechanical properties and adhesion in rabbit intestinal mucosa. In vitro cytotoxicity evaluations such as direct contact assay, MTT assay, and live dead assay performed in RPMI 2650 cells corroborated the non-cytotoxicity of the fabricated matrices with and without propranolol hydrochloride (PL). Detailed drug release studies were conducted in PBS. Drug release in PBS followed the Korsmeyer Peppas model of release. On treating RPMI 2650 cells with the matrix, F-actin and adherens junctional proteins retained integrity, and consequently, drug permeation would proceed through the transcellular transport mechanism. Transepithelial electrical resistance (TEER) measurement of the RPMI 2650 cell monolayer also supported the transcellular transport mechanism. Ex vivo permeation study through porcine buccal mucosa showed 41.26 ± 0.56% PL permeation within 24 h of study. It validated the competence of the electrospun thiolated Zein/PEO matrix for transmucosal drug delivery.

Thymol-loaded Zein-pectin composite nanoparticles as stabilizer to fabricate Pickering emulsion of star anise essential oil for improved stability and antimicrobial activity

The aim of the present study was to prepare a new antimicrobial Pickering emulsion of which the star anise essential oil was added to the oil phase, and to investigate the effect of stabilization by bio-based active nanoparticles consisting of zein and pectin loaded with thymol. First, the thymol-loaded zein/pectin composite nanoparticles (ZTNPs) were fabricated as uniformly distributed spherical nanoparticles with an average diameter of 200 nm through antisolvent precipitation. Second, the effects of nanoparticles' concentration, oil phase ratio, and storage time on the stability of emulsions were explored according to particle size potential, interfacial tension, rheology, and micromorphology. Finally, the antibacterial results showed that Pickering emulsion inhibited Escherichia coli and Staphylococcus aureus compared to the control group by nearly 7 log colony-forming unit/g at 36 h, which was twice as much as the inhibition by thymol or star anise essential oils and ZTNPs. Therefore, the proposed Pickering emulsion with star anise essential oil could be used as a green and safe plant-derived antimicrobial agent in the food industry.

Elucidating the insecticidal mechanisms of zein nanoparticles on Anticarsia gemmatalis (Lepidoptera: Erebidae)

Previous research suggested that positively charged zein nanoparticles [(+)ZNP] were toxic to neonates of Anticarsia gemmatalis Hübner and deleterious to noctuid pests. However, specific modes of action for ZNP have not been elucidated. Diet overlay bioassays attempted to rule out the hypothesis that A. gemmatalis mortality was caused by surface charges from component surfactants. Overlay bioassays indicated that negatively charged zein nanoparticles [(-)ZNP] and its anionic surfactant, sodium dodecyl sulfate (SDS), exhibited no toxic effects when compared to the untreated check. Nonionic zein nanoparticles [(N)ZNP] appeared to increase mortality compared to the untreated check, though larval weights were unaffected. Overlay results for (+)ZNP and its cationic surfactant, didodecyldimethylammonium bromide (DDAB), were found to be consistent with former research indicating high mortalities, and thus, dosage response curves were conducted. Concentration response tests found the LC50 for DDAB on A. gemmatalis neonates was 208.82 a.i./ml. To rule out possible antifeedant capabilities, dual choice assays were conducted. Results indicated that neither DDAB nor (+)ZNP were antifeedants, while SDS reduced feeding when compared to other treatment solutions. Oxidative stress was tested as a possible mode of action, with antioxidant levels used as a proxy for reactive oxygen species (ROS) in A. gemmatalis neonates, which were fed diet treated with different concentrations of (+)ZNP and DDAB. Results indicated that both (+)ZNP and DDAB decreased antioxidant levels compared to the untreated check, suggesting that both (+)ZNP and DDAB may inhibit antioxidant levels. This paper adds to the literature on potential modes of action by biopolymeric nanoparticles.

Spiral grass inspired eco-friendly zein fibrous membrane for multi-efficient air purification

Air pollution, one of the severest threats to public health, may lead to cardiovascular and respiratory illnesses. In order to cope with the deteriorating air pollutant, there is an increasing demand for filters with high purification efficiency, but it's tough to strike a balance between efficiency and resistance. Fabricating an eco-friendly fibrous filter which can capture both PM2.5 and gaseous chemical hazards with high efficiency but under ultra-low resistance is a long-term challenge. Herein, inspired by the interesting ribbon shape of spiral grass, a green and robust 3D nonwoven membrane with controllable hierarchical structure made of self-curved zein nanofibers modified by zeolitic imidazolate framework-8 (ZIF-8) via bi-solvent electrospinning and fumigation welding method was fabricated. The obtained ZIF-8 modified zein membranes showed extraordinary overall performance with high PM2.5 removal efficiency (99.04 %) at a low stress drop (54.87 Pa), first-rate formaldehyde removal efficiency (98.8 %) and excellent photocatalytic antibacterial. In addition, the relatively weak mechanical properties of zein fibrous membranes have been improved via solvent fumigation welding of the joint zein fibers. This study provides a green and convenient insight to the manufacturing of environmentally-friendly zein fibrous membranes with high filtration efficiency, low air resistance and high formaldehyde removal for sustainable air remediation.

Oral Delivery of Bioactive Glass-Loaded Core-Shell Hydrogel Microspheres for Effective Treatment of Inflammatory Bowel Disease

Resolving inflammation and promoting intestinal tissue regeneration are critical for inflammatory bowel disease (IBD) treatment. Bioactive glass (BG) is a clinically approved bone graft material and has been shown to modulate inflammatory response, but it is unknown whether BG can be applied to treat IBD. Here, it is reported that BG attenuates pro-inflammatory response of lipopolysaccharide (LPS)-stimulated macrophages and hence reduces inflammatory damage to intestinal organoids in vitro. In addition, zein/sodium alginate-based core-shell microspheres (Zein/SA/BG) are developed for oral delivery of BG, which helps prevent premature dissolution of BG in the stomach. The results show that Zein/SA/BG protects BG from a gastric-simulated environment while dissolved in an intestinal-simulated environment. When administered to acute and chronic colitis mice model, Zein/SA/BG significantly reduces intestinal inflammation, promotes epithelial tissue regeneration, and partially restores microbiota homeostasis. These findings are the first to reveal the therapeutic efficacy of BG against IBD, which may provide a new therapeutic approach at low cost for effective IBD treatment.

Zein nanospheres assisting inorganic and organic drug combination to overcome stent implantation-induced thrombosis and infection

The complication of stent implantation is the biggest obstacle to the success of its clinical application. In this study, we developed a combination way of 3D printing and the coating technique for preparation of functional polyurethane stents against stent implantation-induced thrombosis and postoperative infection. SEM, XPS, static water contact angle, and XRD demonstrated that the functional polyurethane stent had a 37 μm-thickness membrane composed of zein nanospheres (250-350 nm). Meanwhile, ZnO nanoparticles were encapsulated in zein nanospheres while heparin was adsorbed on the surface, causing 97.1 ± 6.4 % release of heparin in 120 min (first-order kinetic model) and 62.7 ± 5.6 % release of Zn²⁺ in 9 days (Korsmeyer-Peppas model). The mechanical analysis revealed that the functional polyurethane stents had about 8.61 MPa and 2.5 MPa tensile strength and bending strength, respectively. The in vitro biological analysis showed that the functional polyurethane stents had good EA.hy926 cells compatibility (97.9 ± 3.8 %), anti-coagulation response (comparable plasma protein, platelet adhesion and suppressed clotting) and sustained antibacterial activities by comparison with the bare polyurethane stent. The preliminary evaluation by rabbit ex vivo carotid artery intervention experiment demonstrated that the functional polyurethane stents could maintain blood circulation under the continuous stresses of blood flow. Meanwhile, the detailed data from the simulated implant infection experiment in vivo showed the functional polyurethane stents could effectively reduce microbial infection by 3-6 times lower and improve fibrosis and macrophage infiltration.

Interactions between zein and anthocyanins at different pH: Structural characterization, binding mechanism and stability

Zein-anthocyanin nanoparticles (ZACNPs) at different pH values were successfully developed to stabilize anthocyanins based on the self-assembly properties of zein. The structural characterization by the Fourier infrared spectroscopy, fluorescence spectroscopy, differential scanning calorimetry and molecular docking analysis showed that the interactions between anthocyanins and zein were driven by the hydrogen bonds formed between the hydroxyl and carbonyl oxygen groups on anthocyanin glycoside groups and the amino acid residues (glutamine and serine), as well as the hydrophobic interactions from the A or B ring of anthocyanins and the amino acid residues of zein. The binding energy of zein to two anthocyanin monomers cyanidin 3-O-glucoside and delphinidin 3-O-glucoside was 8.2 and 7.4 kcal/mol. Further property examinations of ZACNPs showed that the thermal stability of anthocyanins at a ratio of zein:ACN = 1:0.3 was improved by 56.64 % (90 °C, 2 h), and the storage stability increased by up to 31.11 % at pH 2. In addition, the antioxidant activity of ZACNPs (zein:ACN = 1:0.3) was significantly enhanced, and the DPPH, ABTS radical scavenging activities, FRAP and ORAC value reached 87.73 %, 87.89 %, 435.5 μg/mL, 90.58 μmol/mL at pH 4, respectively. These results suggested that combining zein to anthocyanins is a feasible method to stabilize anthocyanins.

Dynamic investigation of zein-based degradable and hemocompatible coatings for drug-eluting stents: a microfluidic approach

Biodegradable stent coatings have shown great potential in terms of delivering drugs to a damaged vessel wall, and their release profiles are key elements governing the overall performance of drug-eluting stents (DESs). However, release and degradation kinetics are usually not tested under simulated physiological conditions or in dynamic environments, both essential aspects in the design of novel DESs. To bridge this gap, fused silica-based microfluidic systems, with either round or square channel cross-sections, were designed to mimic the microenvironment of a stented vessel. In particular, we fabricated and characterized microfluidic chips based on customizable channels, which were spray-coated with a naturally-derived, rutin-loaded zein solution, to perform a comprehensive study under flow conditions. Dynamic assays after 6 hours showed how the degradation of the zein matrix was affected by the cross-sectional conformation (∼69% vs. ∼61%, square and round channel, respectively) and the simulated blood fluid components (∼55%, round channel with a more viscous solution). The released amount of rutin was ∼81% vs. ∼77% and ∼78% vs. ∼74% from the square and round channels, using the less and more viscous blood-simulated fluids, respectively. Fitting the drug release data to Korsmeyer-Peppas and first-order mathematical models provided further insight into the mechanism of rutin release and coating behavior under flowing conditions. More importantly, whole blood tests with our newly developed microfluidic platforms confirmed the hemocompatibility of our zein-based coating. In detail, in-flow and static studies on the blood cell behavior showed a significant reduction of platelet adhesion (∼73%) and activation (∼93%) compared to the stainless-steel substrate, confirming the benefits of using such naturally-derived coatings to avoid clogging. Overall, our microfluidic designs can provide a key practical tool for assessing polymer degradation and drug release from degradable matrices under flowing conditions, thus aiding future studies on the development of hemocompatible, controlled-release coatings for DESs.

Acaricides containing zein nanoparticles: a tool for a lower impact control of the cattle tick Rhipicephalus microplus

Nanoformulations containing zein nanoparticles (ZN) can promote the stability and protection of molecules with acaricidal activity. The present study sought to develop nanoformulations with ZN associated with cypermethrin (CYPE) + chlorpyrifos (CHLO) + a plant compound (citral, menthol or limonene), characterize them, and verify their efficacy against Rhipicephalus microplus ticks. Additionally, we aimed to assess its safety in nontarget nematodes found in soil at a site subjected to contamination by acaricides. The nanoformulations were characterized by dynamic light scattering and nanoparticle tracking analysis. Nanoformulations 1 (ZN+CYPE+CHLO+citral), 2 (ZN+CYPE+CHLO+menthol), and 3 (ZN+CYPE+CHLO+limonene) were measured for diameter, polydispersion, zeta potential, concentration, and encapsulation efficiency. Nanoformulations 1, 2, and 3 were evaluated in a range from 0.004 to 0.466 mg/mL on R. microplus larvae and caused mortality > 80% at concentrations above 0.029 mg/mL. The commercial acaricide Colosso® (CYPE 15 g + CHLO 25 g + citronellal 1 g) was evaluated also from 0.004 to 0.512 mg/mL and resulted in 71.9% larval mortality at 0.064 mg/mL. Formulations 1, 2, and 3 at 0.466 mg/mL showed acaricidal efficacy of 50.2%, 40.5%, and 60.1% on engorged females, respectively, while Colosso® at 0.512 mg/mL obtained only 39.4%. The nanoformulations exhibited long residual period of activity and lower toxicity to nontarget nematodes. ZN was able to protect the active compounds against degradation during the storage period. Thus, ZN can be an alternative for the development of new acaricidal formulations using lower concentrations of active compounds.

Field applications of zein as a precise nanoscale delivery system for methoxyfenozide

When insecticides are applied in the environment, much of the product does not reach the target pest. Biopolymeric nanoparticles as nanocarriers have the potential to improve insecticide efficacy by improving absorption, coverage, and permeability while protecting the insecticide active ingredient from abiotic conditions and extending efficacy through controlled release. We conducted a series of experiments using a biopolymeric nanoparticle synthesized from zein, a biodegradable maize protein, to compare efficacy of a nanodelivered hydrophobic insect growth regulator (methoxyfenozide) against a commercial formulation. Positively charged zein nanoparticles (empty and loaded with methoxyfenozide) were compared to the formulated product, Intrepid 2F, as a foliar spray in-field on soybean. Chrysodeixis includens (Walker) was used as a model and was fed sprayed soybean leaves to evaluate efficacy of the tested foliar products over time. A separate set of leaves was sampled to measure residue levels of methoxyfenozide (MFZ) over time following foliar application using QuEChERS extraction and high-resolution liquid chromatography-mass spectrometry. Regression analysis found no differences in mortality slopes between positively charged zein nanoparticles loaded with methoxyfenozide [(+)ZNP(MFZ)] and Intrepid 2F, suggesting comparable efficacy of the synthesized nanoparticles to a commercial product. Higher concentrations of MFZ were present in (+)ZNP(MFZ)-treated in leaf tissue at 3 d following spray when compared to Intrepid 2F. The multiyear study results demonstrate that nanoparticles loaded with MFZ are comparable to Intrepid 2F under field conditions, with potential short-term benefits.

Zein Nanoparticles Containing Arginine-Based Surfactants: Physicochemical Characterization and Effect on the Biological Properties

Cationic surfactants carry antimicrobial activity, based on their interaction and disruption of cell membranes. Nonetheless, their intrinsic toxicity limits their applicability. To overcome this issue, a feasible strategy consists of using solid nanoparticles to improve their delivery. The zein nanoparticles were loaded with four cationic arginine-based surfactants: one single chain Nα-lauroyl-arginine (LAM) and three Gemini surfactants Nα Nω-Bis (Nα-lauroyl-arginine) α, ω-diamide) (C₃(LA)₂, C₆(LA)₂ and C₉(LA)₂). Blank and loaded zein nanoparticles were characterized in terms of size, polydispersity and zeta potential. Furthermore, the antimicrobial activity against bacteria and yeasts and the hemolytic activity were investigated and compared to the surfactants in a solution. Nanoparticles were found to be monodisperse, presenting a size of between 180-341 nm, a pdI of <0.2 and a positive zeta potential of between +13 and +53 mV, remaining stable over 365 days. The nanoencapsulation maintained the antimicrobial activity as unaltered, while the extensive hemolytic activity found for the surfactants in a solution was reduced drastically. Nuclear Magnetic Ressonance (NMR), molecular docking and monolayer findings indicated that zein entraps the surfactants, interfering in the surfactant-membrane interactions. Accordingly, the nanoepcasulation of arginine surfactants improved their selectivity, while the cationic charges were free to attack and destroy bacteria and fungi; the aliphatic chains were not available to disrupt the cellular membranes.

3D-Printed Prolamin Scaffolds for Cell-Based Meat Culture

Cultivating meat from muscle stem cells in vitro requires 3D edible scaffolds as the supporting matrix. Electrohydrodynamic (EHD) printing is an emerging 3D-printing technology for fabricating ultrafine fibrous scaffolds with high precision microstructures for biomedical applications. However, edible EHD-printed scaffolds remain scarce in cultured meat (CM) production partly due to special requirements with regard to the printability of ink. Here, hordein or secalin is mixed, which are cereal prolamins extracted from barley or rye, with zein to produce pure prolamin-based inks, which exhibit favorable printability similar to common polycaprolactone ink. Zein/hordein and zein/secalin scaffolds with highly ordered tessellated structures are successfully fabricated after optimizing printing conditions. The prolamin scaffolds demonstrated good water stability and in vitro degradability due to the porous fiber surface, which is spontaneously generated by culturing muscle cells for 1 week. Moreover, mouse skeletal myoblasts (C2C12) and porcine skeletal muscle satellite cells (PSCs) can adhere and proliferate on the fibrous matrix, and a CM slice is produced by culturing PSCs on prolamin scaffolds with high tissue similarity. The upregulation of myogenic proteins shows that the differentiation process is triggered in the 3D culture, demonstrating the great potential of prolamin scaffolds in CM production.

Effects of the maize-derived protein zein, and the milk proteins casein, whey, and α-lactalbumin, on subjective measures of satiety and food intake in normal-weight young men

Protein is considered to be the most satiating food macronutrient and the satiating effect may be dependent on the source of the protein. The maize-derived protein zein and milk protein casein have been shown previously to lower stomach emptying rate more than dairy whey protein, but the effect of zein on satiety has not been evaluated. The objective was to compare the satiating effects of zein and casein, with whey protein and its protein component α-lactalbumin. The study was a randomised crossover design with thirteen normal-weight men (mean age 27.8 years and mean BMI 24.4 kg/m2) consuming isoenergetic (∼4000 kJ, ∼990 kcal) preload mixed meals enriched with Zein, Casein, whey protein isolate (Whey), α-lactalbumin (ALac), or maltodextrin carbohydrate (Carb). Consumption of an ad libitum standardised test meal of chicken fried rice and water provided 360 min following ingestion of the preload meal was measured, and subjective feelings of appetite (hunger, fullness, desire to eat, and prospective food consumption) were assessed using 100-mm visual analogue scales (VAS). There were no differences among the five preload mixed meals in the amount of chicken fried rice consumed at the ad libitum test meal (mean ± sem: 531.6 ± 35.0 g, p = 0.47) or total (preload + test meal) energy intakes (mean ± sem: 5780.5 ± 146.0 kJ, p = 0.29). The subjective VAS appetite ratings and total area under the curve responses for hunger, fullness, desire to eat, and prospective food consumption, were not different following consumption of all five preload mixed meals (p > 0.05). The findings indicate that the effects of zein and casein on satiety were not different from the satiating effects of whey protein and α-lactalbumin.

Zein-Alginate-Phosphatidylcholine Nanocomplex Efficiently Delivers Lycopene and Lutein over Dietary-Derived Carotenoid Mixed Micelles in Caco-2 Cells

This study evaluated the potency of zein-alginate-phosphatidylcholine nanoparticles (NPs) on bioaccessibility/intestinal uptake of encapsulated lycopene (LY) and lutein (LT) versus dietary absorption using simulated digestion and human intestinal Caco-2 cells. LY-zein-alginate-PC (LYZAP) and LT-zein-alginate-PC (LTZAP) NPs yield desired properties, which exhibit sustained release and are suitable for oral administration. Interestingly, co-treatment of LYZAP + LTZAP showed better release of carotenoids instead of individual treatment at intestinal pH. Bioaccessibility, cellular uptake, and basolateral secretion of LY and LT from NPs were significantly enhanced than micellar carotenoids (dietary mode of absorption). The increased absorption of carotenoids from NPs correlated with triglyceride levels. The intestinal cell uptake of carotenoids by nanoencapsulation may be due to endocytosis, paracellular, and SRB-1 protein-mediated transport. Overall, LYZAP and LTZAP NPs possess superior properties to control the release and cellular uptake of unique or distinct carotenoids. The inclusion of alginate and phosphatidylcholine in zein-based nanoencapsulation could be a promising strategy to improve carotenoid bioavailability.

Antibacterial Z-scheme ZnIn2S4/Ag2MoO4 composite photocatalytic nanofibers with enhanced photocatalytic performance under visible light

Considering the biocompatibility of natural proteins and the strong photo-redox capability of Z-scheme heterojunctions, we fabricated Z-scheme ZnIn₂S₄/Ag₂MoO₄@Zein (Z ZA) photocatalytic membranes via electrospinning and in-situ precipitation for enrofloxacin (ENR) degradation. Z ZA exhibit a fiber structure wrapped with ZnIn₂S₄/Ag₂MoO₄ heterojunctions. Photocatalytic studies and various characterization results certified that the Z-scheme structure between ZnIn₂S₄ and Ag₂MoO₄ significantly increases the lifetime and separation efficiency of photogenerated carriers, which in turn enhances the photodegradation of ENR. The degradation rate of Z ZA-10 (ZnIn₂S₄/10 wt% Ag₂MoO₄@Zein) with the highest catalytic activity could reach 100% within 120 min compared with other samples. For ENR degradation, •O₂^- radicals were certified to be the primary active species by trapping experiments, and several possible conversion pathways of ENR in photocatalytic reactions were proposed. Furthermore, the antibacterial rates of Z ZA-20 (ZnIn₂S₄/20 wt% Ag₂MoO₄@Zein) against B. subtilis, P. aeruginosa, S. aureus, and E. coli could reach 90.09%, 89.78%, 84.34%, and 95.31%, respectively. Antibacterial evaluations and cytotoxicity assays demonstrated that Z ZA photocatalytic films had desirable antibacterial properties and low cytotoxicity, rendering them safe and effective for use in the treatment of antibiotic wastewater.

Recent advances in biopolymer-based advanced oxidation processes for dye removal applications: A review

Over the past few years, synthetic dye-contaminated wastewater has attracted considerable global attention due to the low biodegradability and the ability of organic dyes to persist and remain toxic, causing numerous health and environmental concerns. As a result of the recalcitrant nature of those complex organic dyes, the remediation of wastewater using conventional wastewater treatment techniques is becoming increasingly challenging. In recent years, advanced oxidation processes (AOPs) have emerged as a potential alternative to treat organic dyestuffs discharged from industries. The most widely employed AOPs include photocatalysis, ozonation, Fenton oxidation, electrochemical oxidation, catalytic heterogeneous oxidation, and ultrasound irradiation. These processes involve the generation of highly reactive radicals to oxidize organic dyes into innocuous minerals. However, many conventional AOPs suffer from several setbacks, including the high cost, high consumption of reagents and substrates, self-agglomeration of catalysts, limited reusability, and the requirement of light, ultrasound, or electricity. Therefore, there has been significant interest in improving the performance of conventional AOPs using biopolymers and heterogeneous catalysts such as metal oxide nanoparticles (MONPs). Biopolymers have been widely considered in developing green, sustainable, eco-friendly, and low-cost AOP-based dye removal technologies. They inherit intriguing properties like biodegradability, renewability, nontoxicity, relative abundance, and sorption. In addition, the immobilization of catalysts on biopolymer supports has been proven to possess excellent catalytic activity and turnover numbers. The current review provides comprehensive coverage of different AOPs and how efficiently biopolymers, including cellulose, chitin, chitosan, alginate, gelatin, guar gum, keratin, silk fibroin, zein, albumin, lignin, and starch, have been integrated with heterogeneous AOPs in dye removal applications. This review also discusses the general degradation mechanisms of AOPs, applications of biopolymers in AOPs and the roles of biopolymers in AOPs-based dye removal processes. Furthermore, key challenges and future perspectives of biopolymer-based AOPs have also been highlighted.