Electrospun nanofiber-based sensors for the detection of chemical and biological contaminants/hazards in the food industries.

Food contamination reveals a major health risk globally and presents a significant challenge for the food industry. It can stem from biological contaminants like pathogens, parasites, and viruses, or chemical contaminants such as heavy metals, pesticides, drugs, and hormones. There is also the possibility of naturally occurring hazardous chemicals. Consequently, the development of sensing platforms has become crucial to accurately and rapidly identify contaminants and hazards in food products. Electrospun nanofibers (NFs) offer a promising solution due to their unique three-dimensional architecture, large specific surface area, and ease of preparation. Moreover, NFs exhibit excellent biocompatibility, degradability, and adaptability, making monitoring more convenient and environmentally friendly. These characteristics also significantly reduce the detection process of contaminants. NF-based sensors have the ability to detect a wide range of biological, chemicals, and physical hazards. Recent research on NFs-based sensors for the detection of various food contaminants/hazards, such as pathogens, pesticide/drugs residues, toxins, allergens, and heavy metals, is presented in this review.

Polycaprolactone/polyacrylic acid/graphene oxide composite nanofibers as a highly efficient sorbent to remove lead toxic metal from drinking water and apple juice.

Due to the characteristics of electrospun nanofibers (NFs), they are considered a suitable substrate for the adsorption and removal of heavy metals. Electrospun nanofibers are prepared based on optimized polycaprolactone (PCL, 12 wt%) and polyacrylic acid (PAA, 1 wt%) polymers loaded with graphene oxide nanoparticles (GO NPs, 1 wt%). The morphological, molecular interactions, crystallinity, thermal, hydrophobicity, and biocompatibility properties of NFs are characterized by spectroscopy (scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, Thermogravimetric analysis), contact angle, and MTT tests. Finally, the adsorption efficacy of NFs to remove lead (Pb2+) from water and apple juice samples was determined using inductively coupled plasma optical emission spectroscopy (ICP-OES). The average diameter for PCL, PCL/PAA, and PCL/PAA/GO NFs was 137, 500, and 216 nm, respectively. Additionally, the contact angle for PCL, PCL/PAA, and PCL/PAA/GO NFs was obtained at 74.32º, 91.98º, and 94.59º, respectively. The cytotoxicity test has shown non-toxicity for fabricated NFs against the HUVEC endothelial cell line by more than 80% survival during 72 h. Under optimum conditions including pH (= 6), temperature (25 °C), Pb concentration (25 to 50 mg/L), and time (15 to 30 min), the adsorption efficiency was generally between 80 and 97%. The adsorption isotherm model of PCL/PAA/GO NFs in the adsorption of lead metal follows the Langmuir model, and the reaction kinetics follow the pseudo-second-order. PCL/PA/GO NFs have shown adsorption of over 80% in four consecutive cycles. The adsorption efficacy of NFs to remove Pb in apple juice has reached 76%. It is appropriate and useful to use these nanofibers as a high-efficiency adsorbent in water and food systems based on an analysis of their adsorption properties and how well they work.

Advances in sustainable food packaging applications of chitosan/polyvinyl alcohol blend films.

Researchers are addressing environmental concerns related to petroleum-based plastic packaging by exploring biopolymers from natural sources, chemical synthesis, and microbial fermentation. Despite the potential of individual biopolymers, they often exhibit limitations like low water resistance and poor mechanical properties. Blending polymers emerges as a promising strategy to overcome these challenges, creating films with enhanced performance. This review focuses on recent advancements in chitosan/polyvinyl alcohol (PVA) blend food packaging films. It covers molecular structure, properties, strategies for performance improvement, and applications in food preservation. The blend's excellent compatibility and intermolecular interactions make it a promising candidate for biodegradable films. Future research should explore large-scale thermoplastic technologies and investigate the incorporation of additives like natural extracts and nanoparticles to enhance film properties. Chitosan/PVA blend films offer a sustainable alternative to petroleum-based plastic packaging, with potential applications in practical food preservation.

Methylcellulose/chitosan nanofiber-based composites doped with lactoferrin-loaded Ag-MOF nanoparticles for the preservation of fresh apple.

Increasing demand for high-quality fresh fruits and vegetables has led to the development of innovative active packaging materials that exhibit controlled release of antimicrobial/antioxidant agents. In this study, composite biopolymer films consisting of methylcellulose (MC) and chitosan nanofibers (ChNF) were fabricated, which contained lactoferrin (LAC)-loaded silver-metal organic framework (Ag-MOF) nanoparticles. The results indicated that the nanoparticles were uniformly distributed throughout the biopolymer films, which led to improvements in tensile strength (56.1 ± 3.2 MPa), thermal stability, water solubility, swelling index, water vapor barrier properties (from 2.2 ± 2.1 to 1.9 ± 1.9 × 10-11 g. m/m2. s. Pa), and UV-shielding effects. The Ag-MOF-LAC2% films also exhibited strong and long-lasting antibacterial activity against E. coli (19.8 ± 5.2 mm) and S. aureus (20.1 ± 3.2 mm), which was attributed to the slow release of antimicrobial LAC from the films. The composite films were shown to maintain the fresh appearance of apples for at least seven days, which was attributed to their antimicrobial and antioxidant activities. Consequently, these composite films have the potential in the assembly of innovative active packaging materials for protecting fresh fruits and vegetables. However, further work is required to ensure their safety and economic viability.

Sumac (Rhus coriaria L.) anthocyanin loaded-pectin and chitosan nanofiber matrices for real-time monitoring of shrimp freshness.

In this study, pectin (PC)/chitosan nanofiber (ChNF) films containing a novel anthocyanin from sumac extract were successfully developed for freshness monitoring and shelf-life extension of shrimp. The physical, barrier, morphological, color, and antibacterial properties of biodegradable films were evaluated. The addition of sumac anthocyanins to the films caused intramolecular interactions (such as hydrogen bonds) in the film structure, as confirmed by using attenuated total reflectance Fourier transform infrared (ATR-FTIR) analysis, suggesting good compatibility of film ingredients. Also, intelligent films showed significant sensitivity to ammonia vapors and changed color from reddish to olive color at the first 5 min. Moreover, the results showed that PC/ChNF and PC/ChNF/sumac films have significant antibacterial activity against Gram-positive bacteria and Gram-negative bacteria. In addition to the good functional characteristics of the smart film, the resulting films showed acceptable physicomechanical properties. So, PC/ChNF/sumac smart film exhibited the strength = 60 MPa with the flexibility = 23.3 %. Likewise, water vapor barrier reduced from 2.5 (×10-11 g. m/m2. s. Pa) to 2.3 (×10-11 g. m/m2. s. Pa) after adding anthocyanin. The results of the application of intelligent film containing anthocyanins of sumac extract for shrimp freshness monitoring showed that the color of the intelligent film changed from reddish to greenish color after 48 h of storage, which shows the high potential of the produced film for monitoring the spoilage of seafood products.

High performance biopolymeric packaging films containing zinc oxide nanoparticles for fresh food preservation: A review.

Biodegradable food packaging films (FPFs) assembled from sustainable biopolymeric materials are of increasing interest to the food industry due to pollution and health risks resulting from the use of conventional plastic packaging. However, the functional performance of these FPFs is often poorer than that of plastic films, which limits their commercial application. This problem may be partly overcome by incorporating nano-additives like zinc oxide nanoparticles (ZNPs) into the films. The incorporation of ZNPs into FPFs can improve their functional performance. The properties of these films depends on the concentration, dispersion state, and interactions of ZNPs with the biopolymeric matrix in the films. ZNPs-loaded films and coatings are highly effective at preserving a variety of fresh foods. Studies of ZNPs migration through FPFs have shown that the zinc is mainly transported in an ionic form and the amount entering foods is below safety standards. This article reviews recent developments in the design, fabrication, and application of ZNPs-loaded FPFs based on biopolymers, focusing on the impacts of ZNPs on the optical, barrier, mechanical, water sensitivity, and antimicrobial properties of the films. The potential applications of ZNPs-loaded FPFs for fresh food preservation is also discussed.

The impact of cold plasma innovative technology on quality and safety of refrigerated hamburger: Analysis of microbial safety and physicochemical properties.

Atmospheric cold plasma (ACP) is an innovative non-thermal decontamination technology that is considered a great alternative to conventional preservation methods. Most importantly, improving microbial safety along with maintaining the sensory and quality properties of the treated foods, especially for perishable products. Hence, this study aimed to investigate the antimicrobial effects of novel dielectric barrier discharge (DBD) and Jet cold plasma systems and their impact on the physicochemical, color, and sensory properties of refrigerated hamburger samples. In the current study, hamburger samples were inoculated with Staphylococcus aureus, Escherichia coli, Molds and Yeasts microbial suspension (~106 CFU/mL), and then were treated with argon (Ar), helium (He), nitrogen (N), and atmosphere (Atm) gases at different times (s) (0, 30, 60, 90, 180, 360). Similarly, uninoculated samples were considered for total viable count (TVC) testing. The results exhibited that plasma system type, gas type, and treatment time had a significant antimicrobial effect with a microbial reduction ranging from 0.01 to 2 log CFU/g and 0.04-1.5 log CFU/g for DBD and Jet plasma systems, respectively. Also, a treatment time longer than 90 s for DBD and 180 s for jet resulted in a significant reduction in microbial count. The ability of atmospheric cold plasma to inactivate tested foodborne pathogenic bacteria (E. coli and S. aureus) was stronger than other gases because the concentration of O3 and NO gases in atmospheric plasma is higher than other used plasma gases. Surface color measurements (L*, a* and b*) of samples in both methods (DBD and Jet) were not significantly affected. Moreover, samples treated with various plasma gases have indicated insignificant oxidation changes (Thiobarbituric acid assay). These outcomes can assist to reduce microbial contamination and oxidation of hamburgers as a high-consumption and perishable product using ACP technology. Owing to the non-thermal nature of ACP, samples treated with ACP have exhibited no or least effects on the physical, chemical, and sensory features of various food products. As a result, cold plasma innovative technology can be proposed and used as an efficient preservative method to increase the shelf life of food products.

Polychlorinated Biphenyls: A Review of Recent Updates on Food Safety and Environmental Monitoring, Health and Toxicological Implications, and Analysis.

A class of organic chemicals known as polychlorinated biphenyls (PCBs) consists of chlorine, hydrogen, and carbon atoms. High boiling points, chemical stability, non-flammability, and insulating properties have enabled them to be used in various industries. Because of their high toxicity, PCBs were one of the first industrial compounds to be banned from production. These compounds have high-fat solubility with bioaccumulation and biomagnification properties in the environment, food chain, and individuals. Hence, they may have an impact not only on individual organisms but ultimately on whole ecosystems. The main sources of PCB exposure are food and environmental pollutants. In the toxicology of PCBs, oxidative stress plays the most influential function. The induction of CYP1A1 due to the high affinity of PCBs for aryl hydrocarbon receptors is considered a trigger for oxidative stress. Production of reactive oxygen species and depletion of glutathione occur due to phase Ⅰ and Ⅱ metabolism, respectively. Thus, cellular redox balance may be disrupted in the presence of PCBs and their metabolites. Chronic and long-term exposure to these compounds can often lead to life-threatening diseases, like diabetes, obesity, cardiovascular and neurological diseases, cancer, and reproductive and endocrine disorders. We present the current knowledge of the routes of PCB exposure and bioaccumulation, the outlook regarding environmental and food safety, the potential role of PCBs in various diseases, the principal mechanisms responsible for PCB toxicity, and the main detection techniques used for PCBs.

Bio-nanocomposites as food packaging materials; the main production techniques and analytical parameters.

Today, the development of multifunctional and versatile packaging materials based on green ingredients has received a lot of attention from researchers and consumers due to their biodegradability, biocompatibility, sustainability, and renewable nature of biomaterials. These emerging packaging materials in addition to increasing the shelf life of food products (active packaging), informs the consumer about the freshness and spoilage of the product in real-time (smart packaging). The limitations reported for biopolymers-based packaging, such as hydrophilicity and poor mechanical resistance, can be modified and improved by combining biopolymers with various materials including nanomaterials, cross-linkers, bioactive compounds, and other polymers. Consequently, the use of innovative, high performance, and green bio-nanocomposites reveal a promising opportunity to replace conventional non-biodegradable petroleum-based plastics. Likewise, interest in making polymeric bio-nanocomposites for active and smart packaging purposes has been increased in response to a global request for more effective and safe food packaging systems. There are various factors affecting the quality of bio-nanocomposites, such as biomaterials type, additives like nanoparticles, foods type, storage conditions, and the approaches for their preparation. In this review paper, we aimed to discuss the main challenges of the techniques commonly employed to prepare polymeric bio-nanocomposites, including casting, melt mixing (extrusion), electrospinning, and polymerization techniques. The casting has captured scientists' interest more than other techniques, due to the easy handling. The extrusion methods showed a more industrial approach than other techniques in this field. The electrospinning process has attracted a lot of interest due to the production of fibrous membranes, able to encapsulate and stabilize bioactive molecules. The polymerization technique shows less interest amongst scientists due to its complicated conditions, its reaction-based process and the use of toxic and not green reactants and solvents. In conclusion, all techniques should be optimized based on relevant specific parameters to obtain bio-nanocomposites with notable mechanical behaviors, barrier and permeability properties, contact angle/wettability, uniform structures, low cost of production, environmental-friendly nature, migration and penetration, and biodegradability features.

Advances in plant gum polysaccharides; Sources, techno-functional properties, and applications in the food industry - A review.

Gums are biopolymers with many functional and innovative properties in the food industry. They are complex carbohydrate biomolecules capable of bonding with water, generating gel and mucilage structures. Among different gums, plant-based gums (PBGs) are one of the most important groups as they possess key characteristics such as stabilizing potential, viscosity enhancement, emulsifying and surface-active property, extensive adaptability, and affordability leading to their application in the formulation of food products. PBGs are extensively used in the confectionery, encapsulation of flavors and colors, emulsions, carrier agents, as dietary fiber, thickening/foaming agent, formulation of functional foods, and stabilizers in beverages and other food products. More importantly, researchers and food industries have been engrossed to reveal the undisclosed potential of PBGs and the impact of chemical composition and molecular structure on their techno-functional characteristics Therefore, this review study aims to explore the structure and physiochemical/functional properties of PBGs and their application as techno-functional materials in different food industries.

Ultrasound-modified protein-based colloidal particles: Interfacial activity, gelation properties, and encapsulation efficiency.

Proteins are natural amphiphilic polymers that often have good emulsifying, gelling, and structure forming properties. Consequently, they can be used to assemble protein-based colloidal delivery systems for bioactive agents, such as nanoemulsions, protein nanoparticles, or microgels. However, the functional performance of some proteins is limited because of their poor water-solubility, a tendency to aggregate, and or low surface activity, which limits their application for this purpose. Therefore, physicochemical modification is often necessary to improve their technofunctional characteristics. High-intensity ultrasound (HIU) is a non-thermal processing method that has considerable potential for the modification of the structural, physicochemical, and functional properties of proteins. In this article, we review the impact of sonication on the properties of proteins, including their size, charge, surface hydrophobicity, flexibility, solubility, free sulfhydryl groups, and disulfide bond formation. In addition, the influence of sonication on the emulsifying, foaming, gelling, and encapsulation properties of proteins is reviewed. Previous studies show that high-intensity ultrasound treatments have a strong influence on the molecular characteristics of proteins (increasing their solubility, flexibility, and functionality), which improves their ability to form colloidal delivery systems.

Recent progress in the application of plant-based colloidal drug delivery systems in the pharmaceutical sciences.

The potential for utilizing plant-derived components, such as plant proteins, polysaccharides, lipids, and phospholipids, to create targeted drug delivery systems has been demonstrated in recent years. These colloidal delivery systems can encapsulate, protect, and release pharmaceuticals, vitamins, and nutraceuticals, thereby improving their bioavailability and efficacy. Moreover, they have the potential to reduce the side effects associated with some conventional drug formulations, while still achieving controlled or targeted delivery of pharmaceutical agents by various administration routes, including oral, nasal, dermal and inhalation. The pharmacokinetic and pharmacodynamic profiles of drugs can be modulated by altering the composition, dimensions, and structure of drug formulations created using plant-based colloidal delivery systems. The utilization of plant-derived ingredients may also reduce the environmental impact and improve the sustainability of drug formulations. Initially, we provide an overview of the general characteristics and requirements of drug delivery systems. The opportunities and challenges of using plant-derived components to fabricate colloidal particles for drug delivery applications is then discussed. Finally, potential clinical applications of plant-based delivery drug systems are reviewed.

Nano-enabled plant-based colloidal delivery systems for bioactive agents in foods: Design, formulation, and application.

Consumers are becoming increasingly aware of the impact of their dietary choices on the environment, animal welfare, and health, which is causing many of them to adopt more plant-based diets. For this reason, many sectors of the food industry are reformulating their products to contain more plant-based ingredients. This article describes recent research on the formation and application of nano-enabled colloidal delivery systems formulated from plant-based ingredients, such as polysaccharides, proteins, lipids, and phospholipids. These delivery systems include nanoemulsions, solid lipid nanoparticles, nanoliposomes, nanophytosomes, and biopolymer nanoparticles. The composition, size, structure, and charge of the particles in these delivery systems can be manipulated to create novel or improved functionalities, such as improved robustness, higher optical clarity, controlled release, and increased bioavailability. There have been major advances in the design, assembly, and application of plant-based edible nanoparticles within the food industry over the past decade or so. As a result, there are now a wide range of different options available for creating delivery systems for specific applications. In the future, it will be important to establish whether these formulations can be produced using economically viable methods and provide the desired functionality in real-life applications.

A systematic review and meta-analysis of the impacts of glyphosate on the reproductive hormones.

Worldwide use of glyphosate is constantly increasing and its residues are detected in drinking water, agriculture, and food products. There are controversial data regarding the potential reproductive adverse effects of glyphosate herbicide. Therefore, we conducted a systematic review and meta-analysis on the studies in which the alteration of at least one sexual hormone including testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol was reported as a measured outcome in rats. In November 2020, 284 articles were screened, of which eight were eligible for the meta-analysis. An overall considerable effect of glyphosate exposure was found on decreasing of testosterone (7 studies, WMD = - 1.48 ng/mL; 95% CI, - 2.34 to - 0.61; P = 0.001), LH (3 studies, WMD = - 2.03 mIu/mL; 95% CI, - 3.34 to - 0.71; P = 0.003), and FSH (3 studies, WMD = - 2.28 mIu/mL; 95% CI, - 5.12 to 0.55; P = 0.115). According to our results, glyphosate intake could have major effects on the health of reproductive system. Consequently, strict monitoring of the residual glyphosate content in the drinking water, agricultural crops, and food products is necessary.

Efficacy and Safety of the Fixed-Dose Versus Variable-Dose of 4-PCC for Vitamin K Antagonist Reversal: A Comprehensive Systematic Review and Meta-Analysis.

BACKGROUND: The optimal dosing strategy of four-factor prothrombin complex concentrate (4F-PCC) for vitamin K antagonists (VKAs) reversal is unknown. METHODS: We conducted systematic search on the PubMed, SCOPUS, and Embase databases from inception to December 2020 for clinical studies that compared the fixed-dose versus variable-dose of 4-PCC for VKAs reversal with at least one reported clinical outcome. The treatment effects were expressed as relative ratios (RR) with 95% confidence intervals (CIs) and pooled by a random-effects model. RESULTS: Ten studies, including 988 patients, were included. Fixed-dose 4-PCC was associated with lower rate of mortality (RR= 0.65, 95% CI 0.47 to 0.9, p= 0.009), comparable rate of thromboembolic event (TEE) (RR= 1.10, 95%CI 0.44 to 2.80, p= 0.826), and lower goal INR reached (RR= 0.87, 95%CI 0.78 to 0.96, p= 0.007). Less 4-PCC cumulative dose, shorter duration of order-to-needle time, similar hospital length of stay, the comparable time required for INR reversal, higher post-4-PCC INR, and a higher need for additional dose were observed in fixed-dose. CONCLUSIONS: The use of a fixed-dose of 4-PCC may be considered an effective and safe dosing strategy for VKAs reversal in various clinical situations. However, further well-designed, controlled studies should be conducted focusing on clinical outcomes to determine the optimal dose of 4-PCC for VKAs reversal.

The prevalence of foodborne parasites in raw vegetables in Iran: a comprehensive systematic review and meta-analysis.

Foodborne parasites in raw vegetables could cause parasitic infections in humans. An effective approach to the reduction of pathogenic microorganisms in vegetables involves identifying the main sources of contamination and the ecology of the involved microorganisms. This review aimed to evaluate the prevalence of foodborne parasites in raw vegetables in Iran. According to the reviewed studies, the prevalence rate of Ascaris spp., Giardia spp., Toxocara spp., Fasciola, Trichuris, Cryptosporidium, Dicrocoeliasis, Taenia spp., and Entamoeba histolytica was 6 % (95 % CI: 5-8 %), 6 % (95 % CI: 5-7 %), 6 % (95 % CI: 4-7 %), 2 % (95 % CI: 1-2 %), 1 % (95 % CI: 1-2 %), 10 % (95 % CI: 6-15 %), 2 % (95 % CI: 1-3 %), 5 % (95 % CI: 4-6 %), and 3 % (95 % CI: 2-4 %), respectively. According to the standard deviation map, Ilam province was one of the high-risk areas in terms of food-borne parasites in raw vegetables (3 SD < prevalence < 4 SD). Given the key role of raw vegetables in human parasitic contamination, governments must implement more stringent programs for effective wastewater treatment, preventing domestic and wild animals from entering farms, not using human and animal manure on farms, using ready-to-eat packaged vegetables, food safety training for households, implementation of GMP and HACCP in the factory vegetable packaging are required in this regard, especially in the high-risk areas of Iran, such as Ilam province. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40201-021-00714-w.

Recent Advances in the Development of Smart and Active Biodegradable Packaging Materials.

Interest in the development of smart and active biodegradable packaging materials is increasing as food manufacturers try to improve the sustainability and environmental impact of their products, while still maintaining their quality and safety. Active packaging materials contain components that enhance their functionality, such as antimicrobials, antioxidants, light blockers, or oxygen barriers. Smart packaging materials contain sensing components that provide an indication of changes in food attributes, such as alterations in their quality, maturity, or safety. For instance, a smart sensor may give a measurable color change in response to a deterioration in food quality. This article reviews recent advances in the development of active and smart biodegradable packaging materials in the food industry. Moreover, studies on the application of these packaging materials to monitor the freshness and safety of food products are reviewed, including dairy, meat, fish, fruit and vegetable products. Finally, the potential challenges associated with the application of these eco-friendly packaging materials in the food industry are discussed, as well as potential future directions.

Carbohydrate-based films containing pH-sensitive red barberry anthocyanins: Application as biodegradable smart food packaging materials.

A novel pH-sensitive colorimetric film was prepared based on immobilizing red barberry anthocyanins (RBAs) within composite chitin nanofiber (CNF) and methylcellulose (MC) matrices. The incorporation of CNFs and RBAs improved their mechanical properties, moisture resistance, and UV-vis screening properties. Moreover, the RBAs could be used as colorimetric indicators to detect food spoilage because they are sensitive to changes in pH and ammonia gas production. The RBA-halochromic indicator changed from reddish/crimson → pink → yellow with increasing pH, and from pink → yellow with increasing ammonia vapor concentration. Furthermore, the smart films possessed good antioxidant and antimicrobial activity owing to the presence of the RBAs and CNFs. Finally, the validity of the indicator to monitor the freshness/spoilage of a model food (fish) was demonstrated. Overall, this study shows that active/smart films can be assembled from food grade ingredients that can protect and monitor the freshness of products, like meat and fish.

Functional biocompatible nanocomposite films consisting of selenium and zinc oxide nanoparticles embedded in gelatin/cellulose nanofiber matrices.

In recent decades, environmental concerns and increasing consumer demand for healthy and nutritious food products with prolonged shelf life have made the food packaging industry pay more attention to the preparation of multifunctional biodegradable packaging films based on biopolymers containing active components such as antioxidant and antimicrobial agents. In this study, bio-nanocomposite films were fabricated from gelatin (G) and cellulose nanofibers (CNFs), and different concentrations of zinc oxide (ZnO) and/or Selenium (Se) nanoparticles (NPs) by the casting method. The mechanical, barrier, optical, and structural (FTIR, XRD, and SEM) properties of the films were investigated along with their antibacterial and antioxidant features. The incorporation of ZnO and Se NPs improved the physicomechanical and water resistance of G/CNF films. In this regard, the maximum tensile strength value was obtained for the G/CNF containing 5% w/w ZnO NPs (G/CNF/ZnO3) and G/CNF containing 0.1% w/w Se NPs (G/CNF/Se2) films (~2.20-fold and ~2.13-fold higher than the G/CNF film, respectively). Also, G/CNF with 3% w/w ZnO NPs (G/CNF/ZnO2) film had the lowest water vapor permeability and water solubility among all films. Results of the disc diffusion assay showed a stronger antibacterial effect of ZnO NPs compared with Se NPs. The bacterial susceptibility to the antibacterial films was as follows: Listeria monocytogenes > Escherichia coli > Staphylococcus aureus > Pseudomonas fluorescens. The G/CNF films incorporated with Se nanoparticles possessed the higher property of scavenging free radicals in comparison films containing ZnO nanoparticles. Also, the combination of Se NPs and ZnO NPs enhanced the antioxidant effect of the films. In conclusion, gelatin-based edible films containing CNFs, ZnO NPs, and Se NPs can be used in the development of active food packaging products.

Molecular Mechanisms of Salmonella Effector Proteins: A Comprehensive Review.

Salmonella can be categorized into many serotypes, which are specific to known hosts or broadhosts. It makes no difference which one of the serotypes would penetrate the gastrointestinal tract because they all face similar obstacles such as mucus and microbiome. However, following their penetration, some species remain in the gastrointestinal tract; yet, others spread to another organ like gallbladder. Salmonella is required to alter the immune response to sustain its intracellular life. Changing the host response requires particular effector proteins and vehicles to translocate them. To this end, a categorized gene called Salmonella pathogenicity island (SPI) was developed; genes like Salmonella pathogenicity island encode aggressive or modulating proteins. Initially, Salmonella needs to be attached and stabilized via adhesin factor, without which no further steps can be taken. In this review, an attempt has been made to elaborate on each factor attached to the host cell or to modulating and aggressive proteins that evade immune systems. This review includes four sections: (A) attachment factors or T3SS- independent entrance, (B) effector proteins or T3SS-dependent entrance, (c) regulation of invasive genes, and (D) regulation of immune responses.