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Entrapping phytochemical bioactive compounds into nano-structured biocompatible polymers has been successfully utilized for improving cancer treatment efficiency. Silibinin is a potent compound that shows promising anticancer properties. In the present study, the Zein-β-cyclodextrin complex was used to encapsulate silibinin and evaluate the induced cell death type and cytotoxic impacts on human cancer cells. The silibinin-loaded Zein-β cyclodextrin nano-carriers (SZBC-NCs) were synthesized utilizing a gradual ultrasound-mediated homogenization technique and characterized by Zeta potential, DLS, FESEM, and FTIR analysis. The SZBC-NCs' antioxidant activity was studied by conducting ABTS and DPPH radical scavenging assays. Finally, the SZBC-NCs selective toxicity and cellular death induction mechanism were studied on the HT-29 and AGS cancer cells by measuring the cell survival and apoptotic gene (Caspase 3, 9), respectively, which were verified by conducting the DAPI staining analysis. The negatively charged (− 27.47 mV) nanoparticles (286.55 nm) showed significant ABTS and DPPH radical scavenging activity. Moreover, the remarkable decrease in the IC50 concentrations of the SZBC-NCs among the HT-29 and AGS cancer cell lines exhibited their selective cytotoxic potential. Also, the overexpressed apoptotic (Caspases 3 and 9) and down-regulated necrotic (NFKB) gene expressions following the SZBC-NCs treatment doses indicated the apoptotic activity of SZBC-NCs, which were verified by the increased apoptotic morphology of the DAPI-stained HT-29 cancer cells. The antioxidant and colon cancer cell-related apoptotic activity of the SZBC-NCs make it an appropriate anti-colon cancer nano delivery system. Therefore, they can potentially be used as a safe efficient colon cancer treatment strategy. However, further in vivo experiments including animal cancer models have to be studied. [ABSTRACT FROM AUTHOR]

Block copolymers based on fish collagen and chitosan were obtained by ultrasonic irradiation of a blend of homopolymers. The molecular weight of the block copolymer was 310 kDa. The tensile strength of the block copolymer film increases by more than 200% compared to the original chitosan and by 145% compared to films based on a mechanical blend of collagen and chitosan, and amounts to 123 MPa. The growth density of hTert-BJ5ta fibroblast cells on the surface of film samples was calculated. For chitosan, the cell growth density was 97,000 cells/cm2. Films made from mechanical blend were characterized by the lowest adhesion and cell proliferation - 35,000 cells/cm2. However, the block copolymer films had a significant cell growth density - 90,000 cells/cm2, which is close to the values of the original chitosan. The totality of the results obtained shows that compositions based on block copolymers are superior to films made from homopolymers and their blends in mechanical properties, adhesion and proliferation of fibroblast cells, which is important for their use in tissue engineering. [ABSTRACT FROM AUTHOR]

Fisetin (FIS) is a natural flavonoid compound with promising anti-cancer, antioxidant, and neuroprotective properties. Despite these benefits, the low aqueous solubility of fisetin prevents its delivery through intravenous administration resulting in poor bioavailability. Hence, it is important to develop suitable delivery approaches to boost the overall performance of FIS and make it suitable for various medical applications. In this study, we formulated FIS-loaded polymannose (PM) nanoparticles (FIS-PM NPs) to increase their solubility and therapeutic efficacy. In addition, we have nanotized the FIS (Nano FIS) using the antisolvent precipitation method and compared its efficacy with the FIS. The nanoformulations FIS-PM NPs and nanotized FIS were characterized using different techniques such as Dynamic Light Scattering (DLS), UV-vis spectroscopy, scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD). Furthermore, the anticancer effect of FIS and its nanoformulations were tested in breast cancer cell lines (MDA-MB-231). The apoptotic potential of the nanoformulations was examined using different staining techniques and Annexin-V apoptosis assay using flow cytometry. The cell cycle analysis was performed to check the exact mechanism of cell death. The FIS-PM NPs revealed an average size of 250 nm, while Nano FIS showed an average size of 139 nm. FIS-loaded PM NPs showed an encapsulation efficiency of 88% and a drug content of 37%. In vitro drug release studies of the FIS-PM NPs showed a concentration-dependent controlled release of the FIS followed by an initial burst release of ≈ 40 % in phosphate-buffered saline (PBS) at different pH. FIS-PM NPs treated cells showed more cytotoxicity in comparison with nanotized FIS and FIS. We observed more apoptosis in FIS-PM NPs and Nano FIS treated cells compared to FIS and control cells as early as 24 h after the treatment. The cell cycle arrest was seen in the G1 phase of the cells treated with FIS-PM NPs and Nano FIS. In conclusion, the anticancer potential of FIS-PM NPs and Nano FIS has improved in MDA-MB-231 compared to raw FIS which can be attributed to the enhanced solubility of FIS. [ABSTRACT FROM AUTHOR]

In this article, the solvent casting technique was used to prepare wound dressing films based on honey incorporated gellan gum and guar gum biopolymers, and presented the effect of the honey concentration (in the range of 0–10 g on each film). The film structures were assessed by Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. The physical properties of the films were investigated by swelling, degradation, mechanical tests, and water vapor transmission rate. The swelling capacity of the films decreased with an increase in the honey amount, and the presence of honey increased the degradation percentage of the films. The incorporation of honey significantly enhanced the tensile strength of the film, and the increase in honey concentration caused a decrease in the water vapor transmission rate values. The antioxidant activity of the films was determined by DPPH assay, and the films showed good antioxidant abilities. The biocompatibility of the films was evaluated by using an MTT assay with biofilm extract against human skin fibroblast cells, and the wound healing activity of the films was evaluated via in vitro scratch assay. The obtained outcomes showed that the synthesized non-cytotoxic and biocompatible films supported cell migration and proliferation. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Plant proteins have become attractive for biomedical applications such as wound dressing and drug delivery. In this research, nanofibers from pristine zein (plant protein) and zein loaded with tungsten oxide (WO3) were prepared (WO3@zein) using less toxic solvents (ethanol and acetic acid). Morphological and biological properties of the zein nanofiber were determined. Prepared nanofibers were defined by thermogravimetric analysis (TGA), X-ray diffraction (X-RD), Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscopy. The average fiber diameter was unchanged with an increase in WO3 concentration from 0.001 to 0.008%. FT-IR spectroscopy and X-RD indicated the presence of WO3 in WO3@zein nanofibers. In comparison to WO3-free, WO3@zein nanofibers showed higher safety and preserved the anticancer effect of WO3 against human melanoma cell line (A375) melanoma cells compared to WO3-free. Moreover, both WO3-free and WO3@zein caused a fourfold increase in the cellular proliferation of reactive oxygen species (ROS) in the treated A375 cells compared to untreated cells. ROS elevation led to apoptosis-dependent cell death of A375 cells as evidenced by up-regulating the expression of p53-downstream genes (p21 and Bax) (tumor-suppressor gene) while down-regulating the expression of key oncogenes (BCL2 and cyclin D). In conclusion, the prepared nanofiber represents a promising and safe candidate for anticancer applications. [ABSTRACT FROM AUTHOR]

Resveratrol (RSV), a non-flavonoid stilbene polyphenol, possesses anti-carcinogenic activities against all the major stages of cancer. Zein nanoparticles (ZN NPs) have been utilized successfully in delivery of variant therapeuticals by virtue of their histocompatible nature. The goal of this work was to comparatively explore the antiproliferative, pro-apoptotic and oxidative stress potentials of RSV-ZN NPs versus RSV against human colorectal carcinoma HCT-116 cells. ZN-RSV NPs were developed and assayed for particle size analysis and RSV diffusion. The selected formula obtained 137.6 ± 8.3 nm as mean particle size, 29.4 ± 1.8 mV zeta potential, 92.3 ± 3.6% encapsulation efficiency. IC50 of the selected formula was significantly lower against HCT-116 cells versus Caco-2 cells. Also, significantly enhanced cellular uptake was generated from RSV-ZN NPs versus free RSV. Enhanced apoptosis was concluded due to increased percentage cells in G2-M and pre-G1 phases. The pro-apoptotic potential was explained by caspase-3 and cleaved caspase-3 increased mRNA expression in addition to NF-κB and miRNA125b decreased expression. Biochemically, ZN-RSV NPs induced oxidative stress as demonstrated by enhanced reactive oxygen species (ROS) generation and endothelial nitric oxide synthase (eNOS) isoenzyme increased levels. Conclusively, ZN-RSV NPs obtained cell cycle inhibition supported with augmented cytotoxicity, uptake and oxidative stress markers levels in HCT-116 tumor cells in comparison with free RSV. These results indicated intensified chemopreventive profile of RSV due to effective delivery utilizing ZN nano-dispersion against colorectal carcinoma HCT-116 cells. [ABSTRACT FROM AUTHOR]

In the present study, we aimed to evaluate the impact of zein coating (Z) impregnated with ginger extract (GE) and Pimpinella anisum essential oil (AEO) on microbial, chemical and sensory characteristics of beef samples packaged in modified atmosphere (MAP). The treatments were assessed during refrigerated storage for 20 days. GC-MS analysis exhibited that anethole (78.39%) was the dominant component of GE. Results indicated that meat treatment with zein coating containing GE 3% and AEO, resulted in the highest reduction rate of mesophilic bacteria (4.13 log CFU/g), lactic acid bacteria (2.68 log CFU/g), Enterobacteriaceae (3.84 log CFU/g), Pseudomonas spp. (2.74 log CFU/g), and yeasts–molds (1.99 log CFU/g) as compared to the untreated (control) samples. Moreover, the antimicrobial activity of GE enhanced with increasing the concentration and a synergistic effect was observed when combined with AEO. Chemical properties including total volatile nitrogen, thiobarbituric acid reactive substances (TBARS), peroxide value (PV) and pH were notably lower in all treated meats compared to control samples. However, PV and TBARS were higher in MAP only treated meats. Regarding organoleptic properties, Z-GE 3%-A was mostly acceptable the panelists until the last day of experiment. Our findings indicate the potential of zein edible coating incorporated with GE and AEO in reducing the deterioration of fresh beef and improving its shelf life under MAP conditions. [ABSTRACT FROM AUTHOR]

This work analyzed the effect of quinoa flour and zein protein on the rheological, structural, and physicochemical characteristics of gluten-free pasta throughout the production process. Supplementing corn flour with quinoa increased dough protein content and greatly decreased the elastic behavior of the dough. Water diffusivity in the dough matrix during the drying process decreased in the presence of quinoa and was related to the smooth homogeneous surface of the dough. Cooking quality of the final product was explained in terms of the rheological and microstructural characteristics using mathematical models that related dough composition with structural parameters. The presence of zein seemed to weaken the protein network; microstructure was more crumbly with starch granules not completely embedded in the carbohydrate-protein matrix. These structural features explained the lower cooking time, higher breakability, and low cohesiveness of cooked zein-containing pasta. The addition of zein negatively altered the structure of pasta, whereas quinoa flour resulted in a cooked product with good textural properties and higher protein content. [ABSTRACT FROM AUTHOR]

Zein, one of corn processing byproducts, has excellent film-forming ability. However, zein does not have intrinsic antibacterial or antioxidant activity which limits its direct applicability as active food packaging material. In the present study, the rod-shaped micro-sized ZnO crystals were incorporated into zein films to construct zein-based active films as active packaging material with antibacterial property. The morphologies, structural analysis and sizes of ZnO crystals were analyzed by field emission scanning electron microscope and X-ray diffraction. Prepared zein films were evaluated for ZnO loading and distribution. Furthermore, antibacterial activities on Gram-negative bacteria and Gram-positive bacteria were tested by using the disc diffusion method. Lastly, the stability of zein-based active films under the different storage temperature and humidity was investigated. The results showed that zein based-active films had well mechanical properties, stability and antibacterial activities, which were related to the sizes of ZnO crystals in films. [ABSTRACT FROM AUTHOR]

Zein, a prolamin of corn, is a bio-renewable resource that can potentially offer alternatives for petroleum-based polymers in many applications. Nanocomposite formation with the addition of silicate nanoparticles (Laponite) to zein films, cast from 70% ethanol solutions, significantly improved the mechanical, thermal and barrier properties. Based on FTIR findings, a mechanism for zein–Laponite nanocomposite formation is proposed, which suggests Laponite nanoparticles bind to zein molecules through Si–N bond formation. Structural characteristics investigated using AFM and TEM confirmed exfoliation of the nanoparticle. The changes in the surface energy of the films were evaluated using water contact angle measurements and showed an increase in surface hydrophobicity. The Young’s modulus and tensile strength increased with nanoparticle concentration. The glass transition temperature increased, and water vapor permeability decreased with only a small amount of Laponite. [ABSTRACT FROM AUTHOR]

Abstract: Novel zein/tet (tetradecane) and zein/tet/APC (aqueous potassium chloride) micro-encapsulated functional materials were synthesized using a microwave-assisted encapsulation technique. This technique can produce microcapsules in a very short time. In this study, we optimized the methodology used to obtain micro-encapsulation structures based on zein (a maize protein). Zein was mixed with functional materials in ratios of 1:1 and 1:2 (w/v) using ethanol as a solvent. After sonication, each mixture was treated up to 550 s at a power of 450 W in a microwave oven. Subsequently, nitrogen was pumped into the solution for 1 h to remove any residual ethanol from the system and the samples were freeze-dried to yield the dry powder. The thermal performance was analyzed using differential scanning calorimetry and thermogravimetric analysis. The encapsulation morphology and chemical structure were analyzed using scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. Tetradecane was found to be properly encapsulated in the microstructure of zein under two different conditions with an average capsule diameter of 13950 nm. The melting point, crystallization point, and latent heat of encapsulated zein/tet are 4.95, 0.68 °C, and 107 J g−1, respectively. Thermal cycling tests indicated that zein/tet and zein/tet/APC have good thermal stability with negligible changes in their melting and crystallization temperatures. Heat management with tet has been modified using potassium chloride to support a suitable temperature range for food packaging. The encapsulated materials can be potentially used for temperature control during the transport of temperature-sensitive products.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Zeins, storage proteins from maize, are suitable for making biobased thermoplastic materials. The rheological behavior of a commercial zein plasticized with 20 w% glycerol was studied in the molten state by steady-state flow experiments in extrusion conditions and oscillatory rheometry. For low residence times, a shear-thinning viscoelastic behavior was observed, with G″ exceeding G′. After 300 s at 130 °C, the complex viscosity | η | = 7 × 10 ω was found to be similar to that of thermoplastic polymer melts used in fused deposition modeling. However, the ratio between the exponents of the power laws describing G′( ω) and G″( ω) did not meet the typical value of 2 for entangled polymer melts. Moreover, for longer residence times, the viscosity increased and a gelation phenomenon was observed with a crossing over of G′( ω) and G″( ω). Gel times ranged from 6000 s at 120 °C to 1700 s at 150 °C. The evolution of the macromolecular structure assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and high-performance size exclusion chromatography suggested that this gelation phenomenon involves various types of covalent and non-covalent cross-links. Disulfide bonds played a significant role in gelation kinetics despite a very low cysteine residue content in the protein primary structure (about 1 mol%). These results suggested that plasticized zeins initially behave like a low-viscosity non-entangled polymer melt, before cross-linking progressively led to a continuous network. [ABSTRACT FROM AUTHOR]

Maize ( Zea mays L.) grain is an important feedstock for the ethanol-producing industry. However, little is known about the optimum grain quality for optimizing ethanol yielding efficiencies. We specifically investigated the response of ethanol yields (L Mg) to kernel hardness, and its physiological determinant endosperm zein protein profiles, as affected by genotype selection, field nitrogen (N) fertilization, and crop growth environment. We measured ethanol yield and related this to different kernel hardness indicators, kernel composition, and zein profiles. We also described changes in field ethanol yield (L ha), by taking into account the crop yield (Mg ha). Hard endosperm genotypes always yielded less ethanol than softer endosperm ones per grain mass (L Mg). Higher N fertilization rates increased kernel hardness and decreased ethanol yield (L Mg) on soft endosperm dented genotypes but had no effect on hard endosperm ones. Ethanol yield was negatively correlated with kernel density, kernel protein concentration, and Z1 and Z2 zein fractions. Within Z2, 15 kDa β-zein explained the largest ethanol yield variation generated by genotypes, N fertilizations, and growth environments. However, and although these differences were as large as 10%, ethanol field yield (L ha) was mainly driven by crop yields ( r 0.98) due to the large crop yield (Mg ha) differences observed across treatments. Together, our results helped describe the magnitude that changes in maize kernel hardness can have over ethanol yield, both through genotype selection or crop management. A particular Z2 zein protein rises as relevant for future genetic manipulations of maize ethanol yield determination. [ABSTRACT FROM AUTHOR]

Vapor deposition can directly produce ultrastable glasses which are similar to conventional glasses aged over thousands of years. The highly mobile surface layer is believed to accelerate the ageing process of vapor-deposited glasses, but its microscopic kinetics have not been experimentally observed. Here we study the deposition growth kinetics of a two-dimensional colloidal glass at the single-particle level using video microscopy. We observe that newly deposited particles in the surface layer (depth, d < 14 particles) relax via out-of-cage diffusions of individual particles, while particles in the deeper middle layer (14 < d ≲ 100 particles) relax via activation of cooperative-rearrangement regions. These cooperative-rearrangement regions are much larger, more anisotropic and occur more frequently than cooperative-rearrangement regions in the bulk (d ≲ 100 particles) or after deposition. Cooperative-rearrangement regions move towards the surface and released free-volume bubbles at the surface, while the particles within cooperative-rearrangement regions move towards the bulk, resulting in a more compact bulk glass. [ABSTRACT FROM AUTHOR]

Zein powders were subjected to dielectric barrier discharges (DBD) cold plasma (CP) treatment, and the physicochemical and structural properties were investigated. The results indicated that CP treatment decreased the average diameter of zein micelles. It also increased the free sulfhydryl (SH) group concentration and decreased the pH of zein solutions. Significant improvement was observed in solubility of zein in both neutral and acidic water solutions after treatment. Differential scanning calorimetry (DSC) and wide-angle X-ray scattering (WAXS) results indicated the conformation rearrangement for all treated samples. FTIR spectrum confirmed the change of secondary structure for amide I region (1600-1700 cm) after CP treatment. Furthermore, the film-forming properties of zein were also studied. It was found that the increase of CP treatment time could reinforce the tensile strength (TS) and surface hydrophilicity of zein films. It is suggested that the DBD CP treatment technology can improve the utilization and broaden the application field of zein as an effective modification method. [ABSTRACT FROM AUTHOR]

Zein nanoparticles covalently linked to folic acid were hypothesized to sustain the release of the folic acid in addition to targeting cancer cells overexpressing folate-binding receptors, whereas zein nanoparticles with physically entrapped folic acid would only be able to control the release of the bioactive without targeting of cancer cells. The two types of particles, folic acid covalently linked zein nanoparticles (ZN-FA nps) and zein nanoparticles with entrapped folic acid (ZN(FA) nps), were synthesized and the covalent link between folic acid and zein was assessed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (H NMR). Their size, polydispersity index, zeta potential, morphology, and loading capacity were evaluated by dynamic light scattering (DLS), transmission electron microscopy (TEM), and spectrophotometric technique. The release studies of the folic acid preformed in phosphate-buffered saline (PBS) at 37 °C for 7 days concluded that the release of the loaded folic acid was sustained over 7 days for both systems. The cytotoxicity was investigated using a methyl thiazolyl tetrazolium (MTT) assay, and the results showed that zein nanoparticles were biocompatible to HeLa (an overexpressing folate receptor cells) and A549 (a deficient folate receptor cells) cells, which have different levels of folate receptors on surface and both folic acid nanoparticle systems were able to diminish the adverse toxic effect of folic acid to cells. The increased uptake of ZN-FA nps relative to ZN(FA) nps supported the use of ZN-FA nps as targeting nanoagents to cells overexpressing folate receptors. [ABSTRACT FROM AUTHOR]

To explore a novel efficient method in food preservation, edible zein coating which incorporates a polymeric chelator was developed and its preservative effect on commercially manufactured fish balls was investigated. The quality indicators of the fish ball during the storage, including sensory quality, total bacterial count, total basic volatile nitrogen (TVB-N) content, thiobarbituric acid reactive substances (TBARS), and pH value were determined. It has been demonstrated that a zein film containing a polymeric chelator significantly ( P < 0.05) improves the sensory properties, retards the growth of spoilage bacteria, and decreases TVB-N and TBARS values. The increase of the microbial load of fish balls coated with antimicrobial zein during a 16-day refrigeration storage period was less than 1 log cfu/g, while the microbial load increased to about 5 log cfu/g for the control group lacking the coating treatment. Although statistically significant differences in the pH values were not observed between coated and uncoated fish balls ( P > 0.05), fish balls coated with antimicrobial zein maintained a relatively stable state during storage. Zein coating which incorporates a polymeric chelator extends fish ball shelf life to 19 days at 4 °C, being more efficient than zein coating lacking a polymeric chelator (13 days). Clearly, polymeric chelator-incorporated zein film could find application in the preservation of surimi products by preventing the growth of bacteria and oxidation of fat during storage. [ABSTRACT FROM AUTHOR]

In this paper, we report a method to manufacture green nanophotonic sensors made of corn protein zein. The method is direct transfer of three-dimensional metallic (gold and silver) nanostructures onto biodegradable zein films. We have transferred both micro-scale and nano-scale structures with several geometries. Inverted and positive pyramid structures, with 2 μm by 2 μm square base, nanopores, and nanopillars with an approximately 250 nm diameter were successfully transferred onto zein along with 200- and 80-nm-thick gold layers onto pyramids and nanopillars/pores, respectively. Rhodamine 6G was used as a model molecule for surface-enhanced Raman spectroscopy (SERS) measurements, and it was found that the inverted pyramid gold zein sensors had the highest enhancement factor, compared to the other zein sensors. The novel zein sensor platform we developed has the potential to serve as a biodegradable SERS platform for applications in agricultural, medical, and food analysis purposes. [ABSTRACT FROM AUTHOR]

Purpose: In earlier studies, the corn protein zein is found to be suitable as a sustained release agent, yet the range of drugs for which zein has been studied remains small. Here, zein is used as a sole excipient for drugs differing in hydrophobicity and isoelectric point: indomethacin, paracetamol and ranitidine. Methods: Caplets were prepared by hot-melt extrusion (HME) and injection moulding (IM). Each of the three model drugs were tested on two drug loadings in various dissolution media. The physical state of the drug, microstructure and hydration behaviour were investigated to build up understanding for the release behaviour from a zein based matrix for drug delivery. Results: Drug crystallinity of the caplets increases with drug hydrophobicity. For ranitidine and indomethacin, swelling rates, swelling capacity and release rates were pH dependent as a consequence of the presence of charged groups on the drug molecules. Both hydration rates and release rates could be approached by existing models. Conclusion: The drug state and pH dependant electrostatic interactions are hypothesised to influence release kinetics. Both factors can potentially be used to influence release kinetics release, thereby broadening the horizon for zein as a tuneable release agent. [ABSTRACT FROM AUTHOR]

The effects of dynamic high-pressure microfluidization (DHPM) and the addition of quercetagetin on the physical, structural, thermal, and morphological characteristics of zein nanoparticles were investigated. The result of Fourier transform infrared spectroscopy revealed that DHPM treatment caused the structural changes of zein, and the primary interactions between zein and quercetagetin were hydrogen bond and hydrophobic effects. Both of the DHPM treatment and the addition of quercetagetin resulted in the decrease of fluorescence intensity, the improved thermal stability, and the reducing of α-helix and the increase of β-sheets as proved by fluorescence spectra, differential scanning calorimetry thermograms, and circular dichroism spectra, respectively. It was found that the combined DHPM treatment and the addition of quercetagetin with mass ratio of zein to quercetagetin of 40:1 exhibited the morphology of nanospheres with more compact structure and uniform particle distribution. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the destruction of clinically-relevant bacteria within biofilms via the sustained release of the antibiotic tetracycline from zein-based electrospun polymeric fibrous matrices and to demonstrate the compatibility of such wound dressing matrices with human skin cells. Methods: Zein/PCL triple layered fibrous dressings with entrapped tetracycline were electrospun. The successful entrapment of tetracycline in these dressings was validated. The successful release of bioactive tetracycline, the destruction of preformed biofilms, and the viability of fibroblast (FEK4) cells were investigated. Results: The sustained release of tetracycline from these matrices led to the efficient destruction of preformed biofilms from Staphylococcus aureus MRSA252 in vitro, and of MRSA252 and ATCC 25923 bacteria in an ex vivo pig skin model using 1 × 1 cm square matrices containing tetracycline (30 μg). Human FEK4 cells grew normally in the presence of these matrices. Conclusions: The ability of the zein-based matrices to destroy bacteria within increasingly complex in vitro biofilm models was clearly established. An ex vivo pig skin assay showed that these matrices, with entrapped tetracycline, efficiently kill bacteria and this, combined with their compatibility with a human skin cell line suggest these matrices are well suited for applications in wound healing and infection control. [ABSTRACT FROM AUTHOR]

Jamun ( Syzygium cumin L.) is a minor indigenous underexploited and perishable fruit of India. Keeping its perishability in mind, the present study is aimed to evaluate the effectiveness of zein-based coatings enriched with cystein (0.2 %), ascorbic acid (0.2 %), and jamun leaves extract (JLE) (0.2 %) and to evaluate their interactive effects on shelf life and quality of fresh jamun fruits during storage at 10 ± 2 °C for 2 weeks. The results of the present study demonstrated that during storage, uncoated fruit had rapid weight loss, higher decay incidence, high accumulation of sugars, and accelerated softening and ripening than that of all the coated fruit. The content of antioxidants was found to be improved in zein-coated fruits enriched with ascorbic acid (0.2 %) and JLE (0.2 %) and, therefore, exhibited higher antioxidant activity. Moreover, the delayed activity of polygalacturonase (PG) and pectate lyase (PL) was noticed in fruits coated with zein + cystein and zein + JLE and maintained firmness and textural quality of fruit. Consequently, the shelf life of jamun fruit treated with the presently tested coating materials could be extended up to 20 days, while that of control fruit was only 10 days. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the potential of zein as a sole excipient for controlled release formulations prepared by hot melt extrusion. Methods: Physical mixtures of zein, water and crystalline paracetamol were hot melt extruded (HME) at 80°C and injection moulded (IM) into caplet forms. HME-IM Caplets were characterised using differential scanning calorimetry, ATR-FTIR spectroscopy, scanning electron microscopy and powder X-ray diffraction. Hydration and drug release kinetics of the caplets were investigated and fitted to a diffusion model. Results: For the formulations with lower drug loadings, the drug was found to be in the non-crystalline state, while for the ones with higher drug loadings paracetamol is mostly crystalline. Release was found to be largely independent of drug loading but strongly dependent upon device dimensions, and predominately governed by a Fickian diffusion mechanism, while the hydration kinetics shows the features of Case II diffusion. Conclusions: In this study a prototype controlled release caplet formulation using zein as the sole excipient was successfully prepared using direct HME-IM processing. The results demonstrated the unique advantage of the hot melt extruded zein formulations on the tuneability of drug release rate by alternating the device dimensions. [ABSTRACT FROM AUTHOR]

Different strategies to produce thermoplastic materials using starch and zein were studied, aiming to investigate their effect on the compatibility of starch and zein. Research strategies comprised the use of two different plasticizers for starch, two different compatibilizing agents, and two blending procedures. The plasticizers were mixtures of sorbitol and glycerol (SG) or urea and formamide (UF). UF and maleated starch (MS) were used as compatibilizing agents. The blending procedures included: (1) thermoextruding starch and zein as premixed powder materials (TP[Mix]) and (2) coextruding the biopolymers previously thermoplasticized with suitable plasticizers. As observed by the tensile tests, scanning electronic microscopy, and dynamic mechanical analysis, segregation of phases occurred at different extents in all the starch-zein blends. Materials made with MS through the TP[Mix] procedure presented the most severe phases segregation, while the materials made with UF showed higher compatibility between starch and zein. Fourier Transform Infrared Spectroscopy (FTIR) suggests that increased zein content leads to a lower molecular order, which was ascribed to diminished molecular entanglement. Thermogravimetric analysis and FTIR analysis showed that the chemical interaction between starch and zein occurred more extensively in slabs made with UF than those made with MS. In addition, foamability was evaluated for the selected materials using supercritical CO. Neat thermoplasticized starch plasticized with UF and themoplasticized zein with polyethylene-glycol 400 showed good suitability to be foamed, producing foams with porosities above 85 %. Starch plasticized with SG and starch-zein blends yielded compact structures with low porosity values after foaming. [ABSTRACT FROM AUTHOR]

Zein is an amphiphilic protein capable of self-assembly into microspheres. Zein microspheres may form by evaporation-induced self-assembly (EISA) of zein solutions in ethanol/water. The formation of microspheres is of particular interest for the development of delivery systems. Zein solutions in ethanol/water 75 % ( v/ v) were slowly evaporated to promote self-assembly of microspheres. The ethanol content of the solvent decreased during EISA changing solvent polarity which induced self-assembly of zein particles. The growth of zein spheres was modeled from the hydrophobic and hydrophilic contributions to the interfacial free energy ( R = 0.92). The good fit indicated that during EISA zein microspheres increased in size due to hydrophobic interactions between zein molecules. The model may allow the prediction of evaporation time and thus control over microsphere size. [ABSTRACT FROM AUTHOR]

Blends of zein and nylon-6 (55 k) in formic acid were used to produce solution cast films and electrospun fibers. When the amount of nylon-6 was 8 % or less blends were formed that had improved tensile strength and reduced solubility. The blends were analyzed using physical property measurements, DSC and IR spectra. Using between 2 and 8 % nylon-6 provided a 33 % increase in tensile strength. Young's modulus increased by over 50 % in this range. In general elongation was lower for all formulations. Surprisingly the cast films having 0.5-8 % nylon-6 had improved solvent resistance to 90 % ethanol/water. Electrospun fibers were produced from formic acid solutions of zein and nylon-6 where the amount of nylon was 0, 2 and 6. Fibers produced from 27 % spinning solids had average diameters on the order of 0.5 μm. Reducing the spinning solids to 21 % provide slightly smaller fibers however, the fibers had more defects. [ABSTRACT FROM AUTHOR]

An in vitro continuous endosperm callus culture derived from developing endosperm of transformation-amenable maize Hi-II genotype was obtained. The endosperm callus was composed of cells that differentiated into aleurone-like and starchy endosperm-like cell types. This callus has been maintained for 4 yr. Endosperm callus cells transcribe and produce zein proteins at a level similar to developing endosperm tissue. Starchy endosperm cells of the endosperm callus displayed active starch biosynthetic activity. The dual cell physiology of this culture limited the utility of the cell line for promoter analysis and transient assays of gene expression in the current culture conditions. However, because such cell line can be readily initiated and easily maintained for a long period of time, it provides an alternative tool for analysis of transgene expression in endosperm callus derived from transgenic maize lines in Hi-II background. [ABSTRACT FROM AUTHOR]

Maize is used as an alternative to wheat to elaborate foodstuffs for celiac patients in a gluten-free diet. However, some maize prolamins (zeins) contain amino acid sequences that resemble the wheat gluten immunodominant peptides and their integrity after gastrointestinal proteolysis is unknown. In this study, the celiac IgA-immunoreactivity to zeins from raw or nixtamalized grains, before and after peptic/tryptic digestion was evaluated and their possible immunogenicity was investigated by in silico methods. IgA from some celiac patients with HLA-DQ2 or DQ8 haplotypes recognized two alpha-zeins even after peptic/tryptic proteolysis. However, digestion affected zeins after denaturation, reduction, and alkylation, used for identification of prolamins as alpha-zein A20 and A30 by MS/MS sequencing. An in silico analysis indicated that other zeins contain similar sequences, or sequences that may bind even better to the HLA-DQ2/DQ8 molecules compared to the already identified ones. Results concur to indicate that relative abundance of these zeins, along with factors affecting their resistance to proteolysis, may be of paramount clinical relevance, and the use of maize in the formulation and preparation of gluten-free foods must be reevaluated in some cases of celiac disease. [ABSTRACT FROM AUTHOR]

Piroxicam ex vivo release kinetics from zein/pectin drug delivery systems were studied using rat cecum. The piroxicam release kinetic parameters were calculated using a first-order equation and the Peppas equation. The results indicated that diffusion of the therapeutic agent was the rate-limiting step in piroxicam release from the hydrogel microspheres. The created therapeutic drug forms based on biodegradable polymers were an alternative to the peroral administration of most drugs with limited bioavailability. [ABSTRACT FROM AUTHOR]

The use of organic solvents for the preparation of nanofibers are challenged due to their volatile and hazardous behavior. Recently deep eutectic solvents (DES) are widely recognized as non-volatile and non-hazardous solvents which never been utilized directly for nanofabrication via electrospinning. Here, we present the preparation of Zein nanofibers using deep eutectic solvents (DES-Zein). The DES-Zein nanofibers were produced at an optimized polymer concentration of 45% (w/w) with pH 7.3 and electroconductivity 233 mS cm−1. DES-Zein nanofibers showed aligned to tweed like cedar leaf morphology tuned by varying the spreading angle from 0° to 90°. In contrast to hydrophobic conventional Zein nanofibers, DES-Zein nanofibers showed super hydrophilic character and about 200 nm finer average diameter. The proposed method of preparing Zein nanofibers using DES opens a new door to continuous electrospinning with tunable morphology, having potential to be used for environmental and biomedical applications. [ABSTRACT FROM AUTHOR]

In this work, for the first time, zein nanofiber mats loaded with ethanol extracts propolis (EEP) were successfully produced. Raw propolis was extracted by ethanol 70% and total flavonoid content was estimated by aluminum chloride colorimetric method. The anti-microbial activity of the EEP was investigated and compared with amoxicillin via zone of inhibition test against various microorganisms included gram-positive: Staphylococcus aureus, Staphylococcus epidermidis, gram-negative: Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa and fungus: Candida albicans. The EEP showed activity only against gram-positive types and fungus, whereas no activity was observed against gram-negative types. Electrospun zein nanofiber was obtained from 70% ethanolic solutions included different content of zein, 15-40 wt.%. The SEM images revealed a smooth ribbon-like morphology for zein nanofibers without any beads in zein content more than 25 wt.%. As well, the SEM images of electrospun zein nanofibers containing different content of propolis (0-40 wt.% based on the zein content) disclosed the increase in the average size of fibers with propolis content from 264 to 419 nm. This increasing was more probably due to the reduction in ionic conductivity of zein solutions with propolis content. The proteinic nature of zein along with the antimicrobial activity and the herbal nature of the propolis make the obtained mats promising candidate for more evaluation in wound healing study. [ABSTRACT FROM AUTHOR]