Antibacterial properties of nanofibers containing chrysanthemum essential oil and their application as beef packaging

Fatty acid-modified chitosan and nanoencapsulation of essential oils: A snapshot of applications

Chitosan (CS) and its modification with fatty acid (FA) in addition to the nanoencapsulation with essential oils (EOs) have emerged as promising approaches with diverse applications, particularly in food and fruit preservation. This review aims to curate data on the prospects of CS modified with FA as nanostructures, serving as carriers for EOs and its application in the preservation of fruits. A narrative review with no restricted period was used for the general overview of CS and strategies for its modification with FA. Report on CS modified with FA and nanoencapsulation with EO and their applications were appraised. The prospects of CS modified with FA and EO nanoencapsulation in food and fruit preservation were outlined. Most chitosan-fatty acid (CS-FA) studies have found relevance in water, medical and pharmaceutical industries, with few studies on food preservation. CS-FA formulation with EOs shows substantial potential in preserving fruits and will significantly impact the food industry in the future by extending the shelf life of fruits and reducing food waste.

Macrolactin XY, a Macrolactin Antibiotic from Marine-Derived Bacillus subtilis sp. 18

Two new compounds, macrolactin XY (1) and (5R, 9S, 10S)-5-(hydroxymethyl)-1,3,7-decatriene-9,10-diol (2), together with nine known compounds (3-11) were isolated from the marine Bacillus subtilis sp. 18 by the OSMAC strategy. These compounds were evaluated for antibacterial activity against six tested microorganisms. Compounds 1-5 and 7-10 showed varied antibacterial activity, with the minimum inhibitory concentration (MIC) ranging from 3 to 12 μg/mL. Macrolactin XY (1) was found to possess superior antibacterial activity, especially exhibiting significant effectiveness against Enterococcus faecalis. The antibacterial activity mechanism against E. faecalis was investigated. The mechanism may disrupt bacterial cell membrane integrity and permeability, and also inhibit the expression of genes associated with bacterial energy metabolism, as established by the experiments concerning cell membrane potential, SDS-PAGE electrophoresis, cell membrane integrity, and key gene expressions. This study offers valuable insights and serves as a theoretical foundation for the future development of macrolactins as antibacterial precursors.

Intrinsic properties and extrinsic factors of food matrix system affecting the effectiveness of essential oils in foods: a comprehensive review

Essential oils (EOs) have been proved as natural food preservatives because of their effective and wide-spectrum antimicrobial activity. They have been extensively explored for potential applications in food industry, and substantial progresses have been achieved. However well EOs perform in antibacterial tests in vitro, it has generally been found that a higher level of EOs is needed to achieve the same effect in foods. Nevertheless, this unsimilar effect has not been clearly quantified and elaborated, as well as the underlying mechanisms. This review highlights the influence of intrinsic properties (e.g., oils and fats, carbohydrates, proteins, pH, physical structure, water, and salt) and extrinsic factors (e.g., temperature, bacteria characteristics, and packaging in vacuum/gas/air) of food matrix systems on EOs action. Controversy findings and possible mechanism hypotheses are also systematically discussed. Furthermore, the organoleptic aspects of EOs in foods and promising strategies to address this hurdle are reviewed. Finally, some considerations about the EOs safety are presented, as well as the future trends and research prospects of EOs applications in foods. The present review aims to fill the evidenced gap, providing a comprehensive overview about the influence of the intrinsic and extrinsic factors of food matrix systems to efficiently orientate EOs applications.

Proteomics reveals energy limitation and amino acid consumption as antibacterial mechanism of linalool against Shigella sonnei and its application in fresh beef preservation

Meat is often contaminated by food-borne pathogens, resulting in significant economic losses. Linalool from plant essential oils (EOs) has been reported to have excellent antibacterial properties. Therefore, this study aims to elucidate the mechanism of linalool against Shigella sonnei (S. sonnei) based on proteomic and physiological indicators. The results indicated that linalool severely perturbed the expression levels of intracellular proteins, of which 208 were up-regulated and 49 were down-regulated. Moreover, linalool exerted its inhibitory effect mainly through the induction of amino acid limitation and insufficient energy levels based on the pathways involved in differential expressed proteins (DEPs). After 8 h, alkaline phosphatase (AKP) leakage increased 20.96 and 21.52-fold in the MIC and 2MIC groups while protein leakage increased 2.17 and 2.50-fold, respectively, which revealed the potential of linalool on cell structure damage combined with nucleic acid leakage. In addition, the ATP content decreased to 36.92% and 18.84% in the MIC and 2MIC groups, respectively when processed for 8 h. In particular, linalool could effectively control the quality change of fresh beef by measuring pH, total volatile basic nitrogen (TVB-N), total viable counts (TVC) while not affecting its sensory acceptability based on the result of sensory evaluation. This research provides theoretical insights for the development of linalool as a new natural antibacterial agent.

Insight on Incorporation of Essential Oils as Antimicrobial Substances in Biopolymer-Based Active Packaging

The increasing interest in microbiological food safety requires the development of sensitive and reliable analyses and technologies for preserving food products' freshness and quality. Different types of packaging systems are one of the solutions for controlling microbiological activity in foods. During the last decades, the development of biopolymer-based active packaging with essential oil incorporation systems has resulted in technologies with exceptional application potential, primarily in the food industry. There is no doubt that this principle can facilitate food status monitoring, reduce food waste, extend the shelf life, improve the overall quality of food, or indicate a larger problem during the storage, production, and distribution of foodstuffs. On the other hand, most antimicrobial packaging systems are in the development phase, while the sensitivity, selectivity, complexity, and, above all, safety of these materials are just some of the essential questions that need to be answered before they can be widely used. The incorporation of essential oils as antimicrobial substances in biopolymer-based active packaging holds significant promise for enhancing food safety, extending shelf life, and offering more sustainable packaging solutions. While challenges exist, ongoing research and innovation in this field are likely to lead to the development of effective and environmentally friendly packaging systems with enhanced antimicrobial properties.

Essential oil encapsulation by electrospinning and electrospraying using food proteins: A review

Proteins are excellent polymeric materials for encapsulating essential oils (EOs) by electrospinning and electrospraying to protect these compounds and form nanomaterials with active properties. Proteins can encapsulate bioactive molecules by several mechanisms, including surface activity, absorption and stabilization mechanisms, amphiphilic nature, film-forming capacity, foaming, emulsification, and gelation, due to interactions among their functional groups. However, proteins have some limitations in encapsulating EOs by the electrohydrodynamic process. Their properties can be improved by using auxiliary polymers, increasing their charges by adding ionic salts or polyelectrolytes, denaturing their structure by heat, and exposure to specific pH conditions and ionic strength. This review addresses the main proteins used in electrospinning/electrospraying techniques, production methods, their interactions with EOs, bioactive properties, and applications in food matrices. Multivariate analysis associated with bibliometrics of metadata extracted from studies in Web of Science using the keywords electrospinning and essential oil (EO) were used as the search strategy.

Hypericum perforatum Oil and Vitamin A Palmitate-Loaded Gelatin Nanofibers Cross-Linked by Tannic Acid as Wound Dressings

Recent studies in wound dressing applications offer new therapies to promote the wound healing process. The main strategy of this study is to combine the traditional perspective of using medicinal oils with polymeric scaffolds manufactured by an engineering approach to fabricate a potential tissue engineering product that provides both new tissue formation and wound healing. Thus, Hypericum perforatum oil (HPO) and vitamin A palmitate (VAP) incorporated gelatin (Gt) nanofibrous scaffolds were successfully prepared by the electrospinning method. Tannic acid (TA) was used as the cross-linking agent. The amounts of VAP and HPO loaded in the base Gt solution [15% w/v in 4:6 v/v acetic acid/deionized water] were 5 and 50 wt % (based on the weight of Gt), respectively. The obtained scaffolds were studied regarding their microstructure, chemical structure, thermal stability, antibacterial activity, in vitro release study, and cellular proliferation assay. In the light of these studies, it was determined that VAP and HPO were incorporated successfully in Gt nanofibers cross-linked with TA. Release kinetic tests confirmed that the patterns of TA and VAP release were consistent with the Higuchi model, whereas HPO release was consistent with the first-order kinetic model. In addition, this membrane was biocompatible with L929 fibroblast cells and had antibacterial activity and thermal stability. This preliminary study suggests potential applicability of the proposed dressing to treat skin wounds in clinics.

Potential of Essential Oils in the Control of Listeria monocytogenes

Listeria monocytogenes is a foodborne pathogen, the causative agent of listeriosis. Infections typically occur through consumption of foods, such as meats, fisheries, milk, vegetables, and fruits. Today, chemical preservatives are used in foods; however, due to their effects on human health, attention is increasingly turning to natural decontamination practices. One option is the application of essential oils (EOs) with antibacterial features, since EOs are considered by many authorities as being safe. In this review, we aimed to summarize the results of recent research focusing on EOs with antilisterial activity. We review different methods via which the antilisterial effect and the antimicrobial mode of action of EOs or their compounds can be investigated. In the second part of the review, results of those studies from the last 10 years are summarized, in which EOs with antilisterial effects were applied in and on different food matrices. This section only included those studies in which EOs or their pure compounds were tested alone, without combining them with any additional physical or chemical procedure or additive. Tests were performed at different temperatures and, in certain cases, by applying different coating materials. Although certain coatings can enhance the antilisterial effect of an EO, the most effective way is to mix the EO into the food matrix. In conclusion, the application of EOs is justified in the food industry as food preservatives and could help to eliminate this zoonotic bacterium from the food chain.

Fortification of polysaccharide-based packaging films and coatings with essential oils: A review of their preparation and use in meat preservation

As the demand for botanical food additives and eco-friendly food packaging materials grows, the use of essential oils, edible biodegradable films and coatings are becoming more popular in packaging. In this review, we discussed the recent research trends in the use of natural essential oils, as well as polysaccharide-based coatings and films: from the composition of the substrates to preparing formulations for the production of film-forming technologies. Our review emphasized the functional properties of polysaccharide-based edible films that contain plant essential oils. The interactions between essential oils and other ingredients in edible films and coatings including polysaccharides, lipids, and proteins were discussed along with effects on film physical properties, essential oil release, their active role in meat preservation. We presented the opportunities and challenges related to edible films and coatings including essential oils to increase their industrial value and inform the development of edible biodegradable packaging, bio-based functional materials, and innovative food preservation technologies.

Biological and thermodynamic stabilization of lipid-based delivery systems through natural biopolymers; controlled release and molecular dynamics simulations

Nowadays, the use of lipid-based nanocarriers for the targeted and controlled delivery of a variety of hydrophobic and hydrophilic bioactive-compounds and drugs has increased significantly. However, challenges such as thermodynamic instability, oxidation, and degradation of lipid membranes, as well as the unintended release of loaded compounds, have limited the use of these systems in the food and pharmaceutical industries. Therefore, the present study reviews the latest achievements in evaluating the characteristics, production methods, challenges, functional, and biological stabilization strategies of lipid-based carriers (including changes in formulation composition, structural modification, membrane-rigidity, and finally monolayer or multilayer coating with biopolymers) in different conditions, as well as molecular dynamics simulations. The scientists' findings indicate the effect of natural biopolymers (such as chitosan, calcium alginate, pectin, dextran, xanthan, caseins, gelatin, whey-proteins, zein, and etc.) in modifying the external structure of lipid-based carriers, improving thermodynamic stability and resistance of membranes to physicochemical and mechanical tensions. However, depending on the type of bioactive compound as well as the design and production goals of the delivery-system, selecting the appropriate biopolymer has a significant impact on the stability of vesicles and maintaining the bioaccessibility of the loaded-compounds due to the stresses caused by the storage-conditions, formulation, processing and gastrointestinal tract.

Processing interventions for enhanced microbiological safety of beef carcasses and beef products: A review

Chilled beef is inevitably contaminated with microorganisms, starting from the very beginning of the slaughter line. A lot of studies have aimed to improve meat safety and extend the shelf life of chilled beef, of which some have focused on improving the decontamination effects using traditional decontamination interventions, and others have investigated newer technologies and methods, that offer greater energy efficiency, lower environmental impacts, and better assurances for the decontamination of beef carcasses and cuts. To inform industry, there is an urgent need to review these interventions, analyze the merits and demerits of each technology, and provide insight into 'best practice' to preserve microbial safety and beef quality. In this review, the strategies and procedures used to inhibit the growth of microorganisms on beef, from slaughter to storage, have been critiqued. Critical aspects, where there is a lack of data, have been highlighted to help guide future research. It is also acknowledge that different intervention programs for microbiological safety have different applications, dependent on the initial microbial load, the type of infrastructures, and different stages of beef processing.

Essential Oil-Based Nanoparticles as Antimicrobial Agents in the Food Industry

The use of essential oils (EO) loaded with nanoparticles is the most promising alternative to increase food quality and safety. Interesting works describe the antimicrobial properties of EO for pathogen control in natural and processed foods for human health and animal production, also contributing to sustainability. Their association with different nanosystems allows novel developments in the micronutrition, health promotion, and pathogen control fields, preventing the aggravation of bacterial microevolution and combating antibiotic resistance. Benefits to the environment are also provided, as they are biodegradable and biocompatible. However, such compounds have some physicochemical properties that prevent commercial use. This review focuses on recent developments in antimicrobial EO-based nanoparticles and their application in different food matrices.

Antimicrobial Nanomaterials for Food Packaging

Food packaging plays a key role in offering safe and quality food products to consumers by providing protection and extending shelf life. Food packaging is a multifaceted field based on food science and engineering, microbiology, and chemistry, all of which have contributed significantly to maintaining physicochemical attributes such as color, flavor, moisture content, and texture of foods and their raw materials, in addition to ensuring freedom from oxidation and microbial deterioration. Antimicrobial food packaging systems, in addition to their function as conventional food packaging, are designed to arrest microbial growth on food surfaces, thereby enhancing food stability and quality. Nanomaterials with unique physiochemical and antibacterial properties are widely explored in food packaging as preservatives and antimicrobials, to extend the shelf life of packed food products. Various nanomaterials that are used in food packaging include nanocomposites composing nanoparticles such as silver, copper, gold, titanium dioxide, magnesium oxide, zinc oxide, mesoporous silica and graphene-based inorganic nanoparticles; gelatin; alginate; cellulose; chitosan-based polymeric nanoparticles; lipid nanoparticles; nanoemulsion; nanoliposomes; nanosponges; and nanofibers. Antimicrobial nanomaterial-based packaging systems are fabricated to exhibit greater efficiency against microbial contaminants. Recently, smart food packaging systems indicating the presence of spoilage and pathogenic microorganisms have been investigated by various research groups. The present review summarizes recent updates on various nanomaterials used in the field of food packaging technology, with potential applications as antimicrobial, antioxidant equipped with technology conferring smart functions and mechanisms in food packaging.

Current extraction methods and potential use of essential oils for quality and safety assurance of foods

Essential oils (EOs) or vegetable oils have become the focus of several studies because of their interesting bioactive properties. Their application has been successfully explored in active packaging, edible coatings, and as natural flavoring to extend the shelf life of various types of food products. In addition, alternative methods of extraction of EOs (ultrasound-assisted extraction, microwave-assisted extraction, pressurized liquid extraction and supercritical fluid extraction) have been shown to be more attractive than traditional methods since they present better efficiency, shorter extraction times and do not use toxic solvents. This review paper provides a concise and critical view of extraction methods of EOs and their application in food products. The researchers involved in the studies approached in this review were motivated mainly by concern about food quality. Here, we recognize and discuss the major advances and technologies recently used to enable shelf life extension of food products.

Electrospinning as a Promising Process to Preserve the Quality and Safety of Meat and Meat Products

Fresh and processed meat products are staple foods worldwide. However, these products are considered perishable foods and their deterioration depends partly on the inner and external properties of meat. Beyond conventional meat preservation approaches, electrospinning has emerged as a novel effective alternative to develop active and intelligent packaging. Thus, this review aims to discuss the advantages and shortcomings of electrospinning application for quality and safety preservation of meat and processed meat products. Electrospun fibres are very versatile, and their features can be modulated to deliver functional properties such as antioxidant and antimicrobial effects resulting in shelf-life extension and in some cases product quality improvement. Compared to conventional processes, electrospun fibres provide advantages such as casting and coating in the fabrication of active systems, indicators, and sensors. The approaches for improving, stabilizing, and controlling the release of active compounds and highly sensitive, rapid, and reliable responsiveness, under changes in real-time are still challenging for innovative packaging development. Despite their advantages, the active and intelligent electrospun fibres for meat packaging are still restricted to research and not yet widely used for commercial products. Industrial validation of lab-scale achievements of electrospinning might boost their commercialisation. Safety must be addressed by evaluating the impact of electrospun fibres migration from package to foods on human health. This information will contribute into filling knowledge gaps and sustain clear regulations.

Essential oil for the control of fungi, bacteria, yeasts and viruses in food: an overview

This review begins with a general introduction to essential oils (EO) and their relation to food and microorganisms. Classification and characteristics of EO, addressing the major compounds with antimicrobial action. Subsequently, the main microorganisms followed by a collection of the main works published in recent years that approached the influence of the EO on the protection against microorganisms and food decontamination. At last, the major gaps and future perspectives on the subject. Using EO for fighting food contamination is a way of sustainably supplying the need for new antimicrobials to ensure microbial safety and is a viable source to solve the problem of current microbial resistance. Form of application, EO composition and microbiological load are reported as the responsible factors for the treatment's success. The EO's effects on fungi and bacteria are already well known, but its effect on viruses and yeasts is something to be explored.

Electrospun Nanofibers: Current Progress and Applications in Food Systems

Electrospinning has the advantages of simple manufacturing equipment, a low spinning cost, wide range of spinnable materials, and a controllable mild process, which can continuously fabricate submicron or nanoscale ultrafine polymer fibers without high temperature or high pressure. The obtained nanofibrous films may have a large specific surface area, unique pore structure, and easy-to-modify surface characteristics. This review briefly introduces the types and fiber structures of electrospinning and summarizes the applications of electrospinning for food production (e.g., delivery systems for functional food, filtration of beverages), food packaging (e.g., intelligent packaging, antibacterial packaging, antioxidant packaging), and food analysis (e.g., pathogen detection, antibiotic detection, pesticide residue detection, food compositions analysis), focusing on the advantages of electrospinning applications in food systems. Furthermore, the limitations and future research directions of the technique are discussed.

Effect of pepper (Zanthoxylum bungeanum Maxim.) essential oil on quality changes in rabbit meat patty during chilled storage

In this paper, the components of Zanthoxylum bungeanum Maxim. essential oil (ZBMEO) were analyzed. The efficacy of different concentrations of ZBMEO on the change in physical and chemical indicators of the rabbit meat patty was evaluated. Furthermore, kinetics models were employed to calculate the lipid oxidation induction period and microbial growth lag time. GC-MS analysis revealed that the major chemical components in ZBMEO included linalool, limonene, and sabinene. Results of the storage experiment indicated that ZBMEO had a good inhibition effect on lipid and protein oxidation, microbial growth, and formation of TVB-N, as well as slowed down the rate of change in color and pH during the 12 days storage time of rabbit meat. The models showed that adding ZBMEO could delay the lipid oxidation induction period, and extend the microbial growth lag time. Overall data showed that ZBMEO is a promising natural additive to maintain the quality of rabbit meat patty.

Emerging chitosan-essential oil films and coatings for food preservation - A review of advances and applications

With the rising demand for fresh and ready-to-eat foods, antimicrobial packaging has been developed to control or prevent microbial growth as well as maintain food quality and safety. Chitosan is an advanced biomaterial for antimicrobial packaging to meet the growing needs of safe and biodegradable packaging. The application of natural essential oils as antimicrobial agents effectively controls the growth of spoilage and pathogenic microbes. Thus, chitosan edible coatings and films incorporated with essential oils have expanded the general applications of antimicrobial packaging in food products. This review summarized the effect of essential oils on modifying the physicochemical characteristics of chitosan-based films. Notably, the antimicrobial efficacy of the developed composite films or coatings was highlighted. The advances in the preparation methods and application of chitosan films were also discussed. Broadly, this review will promote the potential applications of chitosan-essential oils composite films or coatings in antimicrobial packaging for food preservation.

Role of Nanofibers in Encapsulation of the Whole Cell

In the field of biomaterial research, the electrospinning device is now used to manufacture nanofibers that can be used to encapsulate whole microorganisms such as bacterial cells, funguses, viruses, and even spores. The nanofiber encapsulated cells will have greater significance in the coming future because of their wide variety of applications in various fields. Nanofibers act as microorganism reservoir systems that enhance their properties such as viability, controlled release of products, biomedical applications, and bioremediation. The effect of electrostatic forces on a droplet of liquid polymer or polymer solution is based on electrospinning. Electrospun nanofibers act as ideal native extracellular matrices for microorganisms and have also had a tremendous advantage in drug delivery systems where modern research is still underway. During electrospinning, nearly all microorganisms may be inserted into a polymer matrix that forms a composite nanofiber. The evolution in electrospinning technique over the past few decades has become promising. New ideas have been generated to enhance the techniques and improve the overall applications and properties of nanofibers. This technique has been transformed by the advent of the electrospinning machine. The electrospun nanofibers can be chemically characterized by a wide variety of procedures such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). Electrospinning has various applications, for example, in wastewater treatment, tissue engineering, food industry, drug delivery, agriculture, and cosmetics. Nanofiber encapsulation of microorganisms increased the shelf life of the microorganisms; the cells remain viable for months. It also helps in the control release of bacterial products. The present review demonstrates the role of nanofiber in the encapsulation of the whole cell.

Effect of ethanol extract of black soybean coat on physicochemical properties and biological activities of chitosan packaging film

Chitosan (CS) with an ethanol extract of black soybean coat (EBSC) was prepared, and its physicochemical properties and antioxidant and antibacterial activities were tested. The results showed that EBSC significantly increased the thickness and UV-Vis light barrier ability of the CS-based films, while the swelling degree, water vapor permeability, and tensile strength decreased. The CS-EBSC films had smooth surfaces, compact cross-sections, and no cracks, and they had higher crystallinity than the CS film. Fourier transform-infrared spectroscopy indicated that there were noncovalent bonds (hydrogen bonds) between EBSC and CS. Furthermore, the CS-EBSC III film presented a stronger ABTS radical scavenging ability (66.58%) and could effectively inhibit Bacillus subtilis, Escherichia coli, and Staphylococcus aureus. The lipid oxidation test proved that CS-EBSC films significantly reduced the peroxide value of lard. The results above indicate that CS-EBSC films could be used as an active packaging material to improve the shelf life of food.

Encapsulation of Natural Bioactive Compounds by Electrospinning-Applications in Food Storage and Safety

Packaging is used to protect foods from environmental influences and microbial contamination to maintain the quality and safety of commercial food products, to avoid their spoilage and to extend their shelf life. In this respect, bioactive packaging is developing to additionally provides antibacterial and antioxidant activity with the same goals i.e., extending the shelf life while ensuring safety of the food products. New solutions are designed using natural antimicrobial and antioxidant agents such as essential oils, some polysaccharides, natural inorganic nanoparticles (nanoclays, oxides, metals as silver) incorporated/encapsulated into appropriate carriers in order to be used in food packaging. Electrospinning/electrospraying are receiving attention as encapsulation methods due to their cost-effectiveness, versatility and scalability. The electrospun nanofibers and electro-sprayed nanoparticles can preserve the functionality and protect the encapsulated bioactive compounds (BC). In this review are summarized recent results regarding applications of nanostructured suitable materials containing essential oils for food safety.

Stabilization Techniques of Essential Oils by Incorporation into Biodegradable Polymeric Materials for Food Packaging

Human health, food spoilage, and plastic waste, which are three great topical concerns, intersect in the field of food packaging. This has created a trend to replace synthetic food preservatives with natural ones, to produce bio-functional food packaging, and to shift towards biodegradable polymeric materials. Among the natural bioactive agents, essential oils are gaining more and more attention in food packaging applications due to their various benefits and fewer side-effects. However, their volatility, hydrophobicity, and strong odor and taste limit the direct use in food-related applications. Fixation into polymeric matrices represents a suitable strategy to promote the benefits and reduce the drawbacks. Emulsification and electrospinning are largely used techniques for protection and stabilization of essential oils. These methods offer various advantages in active food packaging, such as controlled release, ensuring long-term performance, decreased amounts of active agents that gain enhanced functionality through increased available surface area in contact with food, and versatility in packaging design. This review focuses on creating correlations between the use of essential oils as natural additives, stabilization methods, and biodegradable polymeric matrices or substrates in developing bioactive food packaging materials. Documentation was performed via the Scopus, ScienceDirect, and PubMed databases, selecting the publications after the year 2018. Particular attention was given to the publications that tested materials on food/food pathogens to evaluate their performances in retarding spoilage. Research gaps were also identified on the topic, materials being tested mainly at short time after preparation without considering the long-term storage that usually occurs in actual practice between production and use, and insufficient research related to upscaling.

Polysaccharides as wall material for the encapsulation of essential oils by electrospun technique

Electrospinning is a versatile, inexpensive and reliable technique for the synthesis of nanometric fibers or particles from polymeric solutions, under a high voltage electric field. The use of natural polysaccharides such as starch, chitosan, pectin, alginate, pullulan, cellulose and dextran as polymeric materials allows the formation of biodegradable fibers and capsules. Bioactive compounds extracted from natural sources, such as essential oils, have been widely studied due to their antioxidant, antimicrobial and antifungal properties. The combination of natural polymers and the electrospinning technique allows the production of structures capable of incorporating these bioactive compounds, which are highly sensitive to degradation reactions. This review describes several approaches to the development of nanofibers and nanocapsules from polysaccharides and the possibility of incorporating hydrophobic compounds, such as essential oils. The review also discusses the use of electrosprayed products incorporated with essential oils for direct application in food or for use as active food packaging.

Effective strategies of sustained release and retention enhancement of essential oils in active food packaging films/coatings

Due to environmental issues caused by plastic packaging and growing consumer demand for fresh and safe food, there is a growing interest in antibacterial active food packaging films/coatings containing plant essential oils (EO). For the effective use of EO-incorporated active films/coatings, EO must be effectively integrated encapsulated in active films/coatings, and the integrated encapsulated EO must be released from active films/coatings slowly during storage to exhibit antibacterial effects more durable. Recently, several promising strategies have been proposed to improve the sustained release and retention enhancement of EO in active films/coatings, including particle encapsulation, nanoemulsion, Pickering emulsions, multilayer system, and electrospinning technology. This article reviewed the latest technologies of sustained release and retention enhancement strategies for encapsulating EO in active films/coatings. The advantages and disadvantages of these sustained release and retention enhancement strategies and their practical applications in food preservation are also introduced.

Natural Anti-Microbials for Enhanced Microbial Safety and Shelf-Life of Processed Packaged Meat

Microbial food contamination is a major concern for consumers and food industries. Consumers desire nutritious, safe and “clean label” products, free of synthetic preservatives and food industries and food scientists try to meet their demands by finding natural effective alternatives for food preservation. One of the alternatives to synthetic preservatives is the use of natural anti-microbial agents in the food products and/or in the packaging materials. Meat and processed meat products are characteristic examples of products that are highly perishable; hence natural anti-microbials can be used for extending their shelf-life and enhancing their safety. Despite several examples of the successful application of natural anti-microbial agents in meat products reported in research studies, their commercial use remains limited. This review objective is to present an extensive overview of recent research in the field of natural anti-microbials, covering essential oils, plant extracts, flavonoids, animal-derived compounds, organic acids, bacteriocins and nanoparticles. The anti-microbial mode of action of the agents, in situ studies involving meat products, regulations and, limitations for usage and future perspectives are described. The review concludes that naturally derived anti-microbials can potentially support the meat industry to provide “clean label”, nutritious and safe meat products for consumers.

Can Sustainable Packaging Help to Reduce Food Waste? A Status Quo Focusing Plant-Derived Polymers and Additives

The promotion of sustainable packaging is part of the European Green Deal and plays a key role in the EU’s social and political strategy. One option is the use of renewable resources and biomass waste as raw materials for polymer production. Lignocellulose biomass from annual and perennial industrial crops and agricultural residues are a major source of polysaccharides, proteins, and lignin and can also be used to obtain plant-based extracts and essential oils. Therefore, these biomasses are considered as potential substitute for fossil-based resources. Here, the status quo of bio-based polymers is discussed and evaluated in terms of properties related to packaging applications such as gas and water vapor permeability as well as mechanical properties. So far, their practical use is still restricted due to lower performance in fundamental packaging functions that directly influence food quality and safety, the length of shelf life, and thus the amount of food waste. Besides bio-based polymers, this review focuses on plant extracts as active packaging agents. Incorporating extracts of herbs, flowers, trees, and their fruits is inevitable to achieve desired material properties that are capable to prolong the food shelf life. Finally, the adoption potential of packaging based on polymers from renewable resources is discussed from a bioeconomy perspective.

Prospects of Polymeric Nanofibers Loaded with Essential Oils for Biomedical and Food-Packaging Applications

Essential oils prevent superbug formation, which is mainly caused by the continuous use of synthetic drugs. This is a significant threat to health, the environment, and food safety. Plant extracts in the form of essential oils are good enough to destroy pests and fight bacterial infections in animals and humans. In this review article, different essential oils containing polymeric nanofibers fabricated by electrospinning are reviewed. These nanofibers containing essential oils have shown applications in biomedical applications and as food-packaging materials. This approach of delivering essential oils in nanoformulations has attracted considerable attention in the scientific community due to its low price, a considerable ratio of surface area to volume, versatility, and high yield. It is observed that the resulting nanofibers possess antimicrobial, anti-inflammatory, and antioxidant properties. Therefore, they can reduce the use of toxic synthetic drugs that are utilized in the cosmetics, medicine, and food industries. These nanofibers increase barrier properties against light, oxygen, and heat, thereby protecting and preserving the food from oxidative damage. Moreover, the nanofibers discussed are introduced with naturally derived chemical compounds in a controlled manner, which simultaneously prevents their degradation. The nanofibers loaded with different essential oils demonstrate an ability to increase the shelf-life of various food products while using them as active packaging materials.

Phytochemical screening and anti-oxidant activity of Sargassum wightii enhances the anti-bacterial activity against Pseudomonas aeruginosa

In this study, the phytochemical, phenolic, flavonoid and bioactive compounds were successfully screened from crude extract of Sargassum wightii by LC-MS analysis after NIST interpretation. Bacterial growth inhibition study result was shown with 24 mm zone inhibition at 200 µg/mL concentration against P. aeruginosa. The increased phenolic content was much closed to gallic acid and the range was observed at 250 μg/mL concentration. In addition, flavonoid contents of the algae extract was indicated more significant with rutin at 200 μg/mL. In result, both the phenolic and flavonoid contents of the extract were more correlated with gallic acid and rutin. Further, the total anti-oxidant and DPPH radical scavenging activities were shown increased activity at 200 μg/mL concentrations. Furthermore, the excellent anti-bacterial alteration result was observed at 200 μg/mL concentration by minimum inhibition concentration. Therefore, the result was revealed that the marine algae Sargassum wightii has excellent phytochemical and anti-oxidant activities, and it has improved anti-bacterial activity against P. aeruginosa.

Electrospun nanofibers food packaging: trends and applications in food systems

Food safety is a bottleneck problem. In order to provide information about advanced and unique food packaging technique, this study summarized the advancements of electrospinning technique. Food packaging is a multidisciplinary area involving food science, food engineering, food chemistry, and food microbiology, and the interest in maintaining the freshness and quality of foods has grown considerably. For this purpose, electrospinning technology has gained much attention due to its unique functions and superior processing. Sudden advancements of electrospinning have been rapidly incorporated into research. This review summarized some latest information about food packaging and different materials used for the packaging of various foods such as fruits, vegetables, meat, and processed items. Also, the use of electrospinning and materials used for the formation of nanofibers are discussed in detail. However, in food industry, the application of electrospun nanofibers is still in its infancy. In this study, different parameters, structures of nanofibers, features and fundamental properties are described briefly, while polymers fabricated through electrospinning with advances in food packaging films are described in detail. Moreover, this comprehensive review focuses on the polymers used for the electrospinning of nanofibers as packaging films and their applications for variety of foods. This will be a valuable source of information for researchers studying various polymers for electrospinning for application in the food packaging industry.

Nanoencapsulation of Promising Bioactive Compounds to Improve Their Absorption, Stability, Functionality and the Appearance of the Final Food Products

The design of functional foods has grown recently as an answer to rising consumers' concerns and demands for natural, nutritional and healthy food products. Nanoencapsulation is a technique based on enclosing a bioactive compound (BAC) in liquid, solid or gaseous states within a matrix or inert material for preserving the coated substance (food or flavor molecules/ingredients). Nanoencapsulation can improve stability of BACs, improving the regulation of their release at physiologically active sites. Regarding materials for food and nutraceutical applications, the most used are carbohydrate-, protein- or lipid-based alternatives such as chitosan, peptide-chitosan and β-lactoglobulin nanoparticles (NPs) or emulsion biopolymer complexes. On the other hand, the main BACs used in foods for health promoting, including antioxidants, antimicrobials, vitamins, probiotics and prebiotics and others (minerals, enzymes and flavoring compounds). Nanotechnology can also play notable role in the development of programmable food, an original futuristic concept promising the consumers to obtain high quality food of desired nutritive and sensory characteristics.

An Insight into the Roles of Dietary Tryptophan and Its Metabolites in Intestinal Inflammation and Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is complex, chronic, and relapsing gastrointestinal inflammatory disorders, which includes mainly two conditions, namely ulcerative colitis (UC) and Crohn's disease (CD). Development of IBD in any individual is closely related to his/her autoimmune regulation, gene-microbiota interactions, and dietary factors. Dietary tryptophan (Trp) is an essential amino acid for intestinal mucosal cells, and it is associated with the intestinal inflammation, epithelial barrier, and energy homeostasis of the host. According to recent studies, Trp and its three major metabolic pathways, namely kynurenine (KYN) pathway, indole pathway, and 5-hydroxytryptamine (5-HT) pathway, have vital roles in the regulation of intestinal inflammation by acting directly or indirectly on the pro/anti-inflammatory cytokines, functions of various immune cells, as well as the intestinal microbial composition and homeostasis. In this review, recent advances in Trp- and its metabolites-associated intestinal inflammation are summarized. It further discusses the complex mechanisms and interrelationships of the three major metabolic pathways of Trp in regulating inflammation, which could elucidate the value of dietary Trp to be used as a nutrient for IBD patients.

Anti-biofilm activity of LC-MS based Solanum nigrum essential oils against multi drug resistant biofilm forming P. mirabilis

Urinary tract infections are second most important diseases worldwide due to the increased amount of antibiotic resistant microbes. Among the Gram negative bacteria, P. mirabilis is the dominant biofilm producer in urinary tract infections next to E. coli. Biofilm is a process that produced self-matrix of more virulence pathogens on colloidal surfaces. Based on the above fact, this study was concentrated to inhibit the P. mirabilis biofilm formation by various in-vitro experiments. In the current study, the anti-biofilm effect of essential oils was recovered from the medicinal plant of Solanum nigrum, and confirmed the available essential oils by liquid chromatography-mass spectroscopy analysis. The excellent anti-microbial activity and minimum biofilm inhibition concentration of the essential oils against P. mirabilis was indicated at 200 µg/mL. The absence of viability and altered exopolysaccharide structure of treated cells were showed by biofilm metabolic assay and phenol-sulphuric acid method. The fluorescence differentiation of P. mirabilis treated cells was showed with more damages by confocal laser scanning electron microscope. Further, more morphological changes of essential oils treated cells were differentiated from normal cells by scanning electron microscope. Altogether, the results were reported that the S. nigrum essential oils have anti-biofilm ability.

Atomic force microscopy in food preservation research: New insights to overcome spoilage issues

A higher level of food safety is required due to the fast-growing human population along with the increased awareness of healthy lifestyles. Currently, a large percentage of food is spoiled during storage and processing due to enzymes and microbial activity, causing huge economic losses to both producers and consumers. Atomic force microscopy (AFM), as a powerful scanning probe microscopy, has been successfully and widely used in food preservation research. This technique allows a non-invasive examination of food products, providing high-resolution images of surface structure and individual polymers as well as the physical properties and adhesion of single molecules. In this paper, detailed applications of AFM in food preservation are reviewed. AFM has been used to provide comprehensive information in food preservation by evaluating the spoilage with its related structure modification. By utilizing AFM imaging and force measurement function, the main mechanisms involved in the loss of food quality and preservation technologies development can be further elucidated. It is also capable of exploring the activities of enzymes and microbes in influencing the quality of food products during storage. AFM provides comprehensive solutions to overcome spoilage issues with its versatile functions and high-throughput outcomes. Further research and development of this novel technique in order to solve integrated problems in food preservation are necessary.