Biodegradable active food packaging structures based on hybrid cross-linked electrospun polyvinyl alcohol fibers containing essential oils and their application in the preservation of chicken breast fillets

Application of essential oils as slow-release antimicrobial agents in food preservation: Preparation strategies, release mechanisms and application cases

Food spoilage caused by foodborne microorganisms will not only cause significant economic losses, but also the toxins produced by some microorganisms will also pose a serious threat to human health. Essential oil (EOs) has significant antimicrobial activity, but its application in the field of food preservation is limited because of its volatile, insoluble in water and sensitive to light and heat. Therefore, in order to solve these problems effectively, this paper first analyzed the antibacterial effect of EOs as an antimicrobial agent on foodborne bacteria and its mechanism. Then, the application strategies of EOs as a sustained-release antimicrobial agent in food preservation were reviewed. On this basis, the release mechanism and application cases of EOs in different antibacterial composites were analyzed. The purpose of this paper is to provide technical support and solutions for the preparation of new antibacterial packaging materials based on plant active components to ensure food safety and reduce food waste.

Investigating How the Properties of Electrospun Poly(lactic acid) Fibres Loaded with the Essential Oil Limonene Evolve over Time under Different Storage Conditions

Essential oils have been identified as effective natural compounds to prevent bacterial infections and thus are widely proposed as bioactive agents for biomedical applications. Across the literature, various essential oils have been incorporated into electrospun fibres to produce materials with, among others, antibacterial, anti-inflammatory and antioxidant activity. However, limited research has been conducted so far on the effect of these chemical products on the physical characteristics of the resulting composite fibres for extended periods of time. Within this work, electrospun fibres of poly(lactic acid) (PLA) were loaded with the essential oil limonene, and the impact of storage conditions and duration (up to 12 weeks) on the thermal degradation, glass transition temperature and mechanical response of the fibrous mats were investigated. It was found that the concentration of the encapsulated limonene changed over time and thus the properties of the PLA-limonene fibres evolved, particularly in the first two weeks of storage (independently from storage conditions). The amount of limonene retained within the fibres, even 4 weeks after fibre generation, was effective to successfully inhibit the growth of model microorganisms Escherichia coli, Staphylococcus aureus and Bacillus subtilis. The results of this work demonstrate the importance of evaluating physical properties during the ageing of electrospun fibres encapsulating essential oils, in order to predict performance modification when the composite fibres are used as constituents of medical devices.

Colorimetric Films Based on Polyvinyl Alcohol and Anthocyanins Extracted from Purple Tomato to Monitor the Freshness of Shrimp

Anthocyanin extracts from purple tomato (PTA) were incorporated with polyvinyl alcohol (PVA), resulting in a series of colorimetric PVA/PTA films with PTA concentrations of 0%, 1%, 3%, and 5% (based on PVA). The role of anthocyanin on color response, Fourier-transform infrared (FTIR), thickness, water content, mechanical properties, antioxidant activity, and water vapor permeability (WVP) through the films was examined. In addition, its application in smart packaging to assess the freshness of shrimp was studied. It was found that the tensile strength, contact angle and WVP of PVA/PTA films increases with the addition of more PTA, while the elongation at break and water content decreased. FTIR analysis showed that there are interactions between PTA and the PVA matrix. The addition of anthocyanins caused significant improvement in the antioxidant properties of PVA films. Furthermore, the total volatile alkaline nitrogen (TVB-N), total plate count (TPC), and pH value of shrimp were monitored after 4 days of refrigeration, and the color change of the indexes was recorded. The PVA/PTA films changed color from purple to yellow-green during the storage time of 0-4 days for shrimp. This suggests that the film could be used in smart packaging as a real-time freshness indicator for shrimp.

Alginate-based edible coating with oregano essential oil/β-cyclodextrin inclusion complex for chicken breast preservation

A sodium alginate (SA) edible coating containing oregano essential oil (OEO)/β-cyclodextrin (β-CD) inclusion complexes (SA/OEO-MP coating) was developed to extend the shelf life of fresh chicken breast during refrigeration storage. First, OEO was inserted into the hydrophobic interior of β-CD to form an inclusion complex (OEO-MP) that maintained its excellent antioxidant and antibacterial activities. The formed OEO-MP was characterized using fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). In addition, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) results demonstrated that β-CD could improve the thermal stability of OEO. The encapsulation efficiency reached 71.6 %, and OEO was released continuously from the OEO-MP. The lipid oxidation, total viable count (TVC) and sensory properties of chicken breasts were regularly monitored when OEO-MP was incorporated into the SA coating for chicken breast preservation. Compared with the uncoated group, the SA/OEO-MP-coated groups showed significantly reduced increases in pH, thiobarbituric acid reactive substances (TBARS), total volatile base nitrogen (TVB-N), and TVC, especially in the SA/OEO-MP1 group. In summary, the SA/OEO-MP coating could preserve the chicken breast by reducing lipid oxidation and inhibiting the proliferation of microorganisms. It would be developed as a prospective edible packaging for chicken preservation.

Electrospun Nanofibers for Functional Food Packaging Application

With the strengthening of the public awareness of food safety and environmental protection, functional food packaging materials have received widespread attention. Nanofibers are considered as promising packaging materials due to their unique one-dimensional structure (high aspect ratio, large specific surface area) and functional advantages. Electrospinning, as a commonly used simple and efficient method for preparing nanofibers, can obtain nanofibers with different structures such as aligned, core-shell, and porous structures by modifying the devices and adjusting the process parameters. The selection of raw materials and structural design of nanofibers can endow food packaging with different functions, including antimicrobial activity, antioxidation, ultraviolet protection, and response to pH. This paper aims to provide a comprehensive review of the application of electrospun nanofibers in functional food packaging. Advances in electrospinning technology and electrospun materials used for food packaging are introduced. Moreover, the progress and development prospects of electrospun nanofibers in functional food packaging are highlighted. Meanwhile, the application of functional packaging based on nanofibers in different foods is discussed in detail.

Electrospun polyvinyl alcohol/chitosan nanofibers incorporated with 1,8-cineole/cyclodextrin inclusion complexes: Characterization, release kinetics and application in strawberry preservation

Development of food packaging systems containing essential oils (EOs) has gained increased attention recently. However, the instability of EOs restricts their application. Therefore, effective encapsulation of EOs is demanded for their protection and controlled release. In this work, 1,8-cineole, the major component in Eucalyptus globulus essential oil, was encapsulated into hydroxypropyl-β-cyclodextrin to form an inclusion complex, which was then incorporated into polyvinyl alcohol and chitosan composite polymer to fabricate nanofibrous film via electrospinning. The film with 40% (w/w) of inclusion complexes showed enhanced barrier and mechanical properties, and the release of 1,8-cineole from the film was sustained and dominated by the non-Fick diffusion. Moreover, this film could extend the shelf life of strawberries to 6 days at 25 ℃. This work suggested dual encapsulation of EOs by cyclodextrin and electrospun nanofibers is an ideal strategy to improve the availability of EOs, and the produced film is promising for food preservation.

What is the role of active packaging in the future of food sustainability? A systematic review

Nowadays, the strong increase in products consumption, the purchase of products on online platforms as well as the requirements for greater safety and food protection are a concern for food and packaging industries. Active packaging brings huge advances in the extension of product shelf-life and food degradation and losses reduction. This systematic work aims to collect and evaluate all existing strategies and technologies of active packaging that can be applied in food products, with a global view of new possibilities for food preservation. Oxygen scavengers, carbon dioxide emitters/absorbers, ethylene scavengers, antimicrobial and antioxidant active packaging, and other active systems and technologies are summarized including the products commercially available and the respective mechanisms of action. © 2022 Society of Chemical Industry.

Recent Progress of Electrospun Herbal Medicine Nanofibers

Herbal medicine has a long history of medical efficacy with low toxicity, side effects and good biocompatibility. However, the bioavailability of the extract of raw herbs and bioactive compounds is poor because of their low water solubility. In order to overcome the solubility issues, electrospinning technology can offer a delivery alternative to resolve them. The electrospun fibers have the advantages of high specific surface area, high porosity, excellent mechanical strength and flexible structures. At the same time, various natural and synthetic polymer-bound fibers can mimic extracellular matrix applications in different medical fields. In this paper, the development of electrospinning technology and polymers used for incorporating herbal medicine into electrospun nanofibers are reviewed. Finally, the recent progress of the applications of these herbal medicine nanofibers in biomedical (drug delivery, wound dressing, tissue engineering) and food fields along with their future prospects is discussed.

The Caucasian Whortleberry Extract/Myrtle Essential Oil Loaded Active Films: Physicochemical Properties and Effects on Quality Parameters of Wrapped Turkey Breast Meat

In this research work, the effects of myrtle essential oil (MEO) and Caucasian whortleberry extract (CWE) as natural additives were investigated on mechanical, physico-mechanical and antimicrobial properties of gellan/polyvinyl alcohol (G/PVA) film. Then, optimal blend active films were used for the wrapping of turkey breast meat stored at low temperature (4 ± 1 °C) for 15 days and chemical and sensory properties of wrapped meats were evaluated. The addition of MEO and CWE decreased tensile strength and increased the strain at the break of the films (p ≤ 0.05). Additionally, with increasing the amount of MEO and CWE, the permeability to water vapor (WVP) and the moisture content (MC) of the films decreased (p ≤ 0.05). MIC test showed that MEO and CWE were effective against S. aureus, E. coli, S. typhimurium, and P. fluorescens. at the concentrations of 5-6 and 15-17 mg/mL, respectively. Different microbiological, chemical, and sensory tests indicated that active films significantly enhanced the shelf life of turkey breast meat (p ≤ 0.05). Therefore, based on our finding in this study, the use of these active and biodegradable packagings can be effective and useful for protecting the microbial and sensory quality of turkey breast meat.

Phytochemical Profiling, Antioxidant, Antimicrobial and Cholinesterase Inhibitory Effects of Essential Oils Isolated from the Leaves of Artemisia scoparia and Artemisia absinthium

The current studies were focused on the phytochemical profiling of two local wild Artemisia species, Artemisia scoparia and Artemisia absinthium leaves’ essential oils, extracted via the hydro distillation method along with evaluation of their antioxidant as well as antimicrobial effects. The constituents of EOs were identified using a combined gas chromatography-mass spectrometric (GC-MS) technique. A total of 25 compounds in A. scoparia essential oil (EOAS) were identified, and 14 compounds with percentage abundance of >1% were tabulated, the major being tocopherol derivatives (47.55%). A total of nine compounds in Artemisia absinthium essential oil (EOAA) were enlisted (% age > 1%), the majority being oleic acid derivatives (41.45%). Strong antioxidant effects were pronounced by the EOAS in DPPH (IC50 = 285 ± 0.82 µg/mL) and in ABTS (IC50 = 295 ± 0.32 µg/mL) free radical scavenging assays. Both the EOs remained potent in inhibiting the growth of bacterial species; Escherichia coli (55−70%) and Shigella flexneri (60−75%) however remained moderately effective against Bacillus subtilis as well as Staphylococcus aureus. Both EOAS and EOAA strongly inhibited the growth of the tested fungal species, especially Aspergillus species (up to 70%). The oils showed anti-cholinesterase potential by inhibiting both Acetylcholinesterase (AChE; IC50 = 30 ± 0.04 µg/mL (EOAS), 32 ± 0.05 µg/mL (EOAA) and Butyrylcholinesterase (BChE; IC50 = 34 ± 0.07 µg/mL (EOAS), 36 ± 0.03 µg/mL (EOAA). In conclusion, the essential oils of A. scoparia and A. absinthium are promising antioxidant, antimicrobial and anticholinergic agents with a different phytochemical composition herein reported for the first time.

New perspectives on electrospun nanofiber applications in smart and active food packaging materials

Packaging plays a critical role in determining the quality, safety, and shelf-life of many food products. There have been several innovations in the development of more effective food packaging materials recently. Polymer nanofibers are finding increasing attention as additives in packaging materials because of their ability to control their pore size, surface energy, barrier properties, antimicrobial activity, and mechanical strength. Electrospinning is a widely used processing method for fabricating nanofibers from food grade polymers. This review describes recent advances in the development of electrospun nanofibers for application in active and smart packaging materials. Moreover, it highlights the impact of these nanofibers on the physicochemical properties of packaging materials, as well as the application of nanofiber-loaded packaging materials to foods, such as dairy, meat, fruit, and vegetable products.

Transdermal therapeutic system: Study of cellulose nanocrystals influenced methylcellulose-chitosan bionanocomposites

Over the past few years, there is a drive toward the fabrication and application of bio-based non-cytotoxic drug carriers. Cellulose nanocrystals (CNCs) have gotten immense research attention as a promising bioderived material in the biomedical field due to its remarkable properties. The delivery of analgesic and anti-inflammatory drug, ketorolac tromethamine (KT) by transdermal route is stipulated herewith to fabricate suitable transdermal therapeutic systems. We have synthesized CNCs from jute fibers and aim to develop a non-cytotoxic polymer-based bionanocomposites (BNCs) transdermal patch, formulated with methylcellulose (MC), chitosan (CH), along with exploration of CNCs for sustained delivery of KT, where CNCs act as nanofiller and elegant nanocarrier. CNCs reinforced MCCH blends were prepared via the solvent evaporation technique. The chemical structure, morphology, and thermal stability of the prepared bionanocomposites formulations were studied by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), TGA, DSC, DMA, and SEM. The In vitro drug release studies were executed using Franz diffusion cells. The BNC patches showed in-vitro cytocompatibility and the drug release study revealed that BNC containing 1 wt% CNCs presented the best-sustained drug release profile. The bioderived CNCs appear to enhance the BNCs drug's bioavailability, which could have a broad prospect for TDD applications.

Electrospun Nisin-Loaded Poly(ε-caprolactone)-Based Active Food Packaging

Packaging for fresh fruits and vegetables with additional properties such as inhibition of pathogens grown can reduce food waste. With its biodegradability, poly(ε-caprolactone) (PCL) is a good candidate for packaging material, especially in the form of an electrospun membrane. The preparation of nonwoven fabric of PCL loaded with food additive, antimicrobial nisin makes them an active packaging with antispoilage properties. During the investigation of the nonwoven fabric mats, different concentrations of nisin were obtained from the solution of PCL via the electrospinning technique. The obtained active porous PCL loaded with varying concentrations of nisin inhibited the growth of Staphylococcus aureus and Escherichia coli. Packages made of PCL and PCL/nisin fibrous mats demonstrated a prolongation of the fruits’ freshness, improving their shelf life and, consequently, their safety.

Cyanine-Doped Nanofiber Mats for Laser Tissue Bonding

In spite of an extensive body of academic initiatives and innovative products, the toolkit of wound dressing has always revolved around a few common concepts such as adhesive patches and stitches and their variants. Our work aims at an alternative solution for an immediate restitutio ad integrum of the mechanical functionality in cutaneous repairs. We describe the fabrication and the application of electrospun mats of bioactive nanofibers all made of biocompatible components such as a natural polysaccharide and a cyanine dye for use as laser-activatable plasters, resembling the ultrastructure of human dermis. In particular, we investigate their morphological features and mechanical moduli under conditions of physiological relevance, and we test their use to bind a frequent benchmark of connective tissue as rabbit tendon and a significant case of clinical relevance as human dermis. Altogether, our results point to the feasibility of a new material for wound dressing combining translational potential, strength close to human dermis, extensibility exceeding 15% and state-of-art adhesive properties.

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.

Potential of Polyamide Nanofibers With Natamycin, Rosemary Extract, and Green Tea Extract in Active Food Packaging Development: Interactions With Food Pathogens and Assessment of Microbial Risks Elimination

Increasing microbial safety and prolonging the shelf life of products is one of the major challenges in the food industry. Active food packaging made from nanofibrous materials enhanced with antimicrobial substances is considered a promising way. In this study, electrospun polyamide (PA) nanofibrous materials functionalized with 2.0 wt% natamycin (NAT), rosemary extract (RE), and green tea extract (GTE), respectively, were prepared as active packaging and tested for the food pathogens Escherichia coli, Listeria monocytogenes, Salmonella enterica, and Staphylococcus aureus. The PAs exhibited: (i) complete retention of bacterial cells reaching 6.0–6.4 log₁₀removal, (ii) antimicrobial activity with 1.6–3.0 log₁₀suppression, and (iii) antibiofilm activity with 1.7–3.0 log₁₀suppression. The PAs prolonged the shelf life of chicken breast; up to 1.9 log₁₀(CFU/g) suppression of total viable colonies and 2.1 log₁₀(CFU/g) suppression of L. monocytogenes were observed after 7 days of storage at 7°C. A beneficial effect on pH and sensory quality was verified. The results confirm microbiological safety and benefits of PA/NAT, PA/RE, and PA/GTE and their potential in developing functional and ecological packaging.

Advancements in Biodegradable Active Films for Food Packaging: Effects of Nano/Microcapsule Incorporation

Food packaging plays a fundamental role in the modern food industry as a main process to preserve the quality of food products from manufacture to consumption. New food packaging technologies are being developed that are formulated with natural compounds by substituting synthetic/chemical antimicrobial and antioxidant agents to fulfill consumers’ expectations for healthy food. The strategy of incorporating natural antimicrobial compounds into food packaging structures is a recent and promising technology to reach this goal. Concepts such as “biodegradable packaging”, “active packaging”, and “bioactive packaging” currently guide the research and development of food packaging. However, the use of natural compounds faces some challenges, including weak stability and sensitivity to processing and storage conditions. The nano/microencapsulation of these bioactive compounds enhances their stability and controls their release. In addition, biodegradable packaging materials are gaining great attention in the face of ever-growing environmental concerns about plastic pollution. They are a sustainable, environmentally friendly, and cost-effective alternative to conventional plastic packaging materials. Ultimately, a combined formulation of nano/microencapsulated antimicrobial and antioxidant natural molecules, incorporated into a biodegradable food packaging system, offers many benefits by preventing food spoilage, extending the shelf life of food, reducing plastic and food waste, and preserving the freshness and quality of food. The main objective of this review is to illustrate the latest advances in the principal biodegradable materials used in the development of active antimicrobial and antioxidant packaging systems, as well as the most common nano/microencapsulated active natural agents incorporated into these food-packaging materials.

Effect of PVOH/PLA + Wax Coatings on Physical and Functional Properties of Biodegradable Food Packaging Films

Biodegradable polymers suffer from inherent performance limitations that severely limit their practical application. Their functionalization by coating technology is a promising strategy to significantly improve their physical properties for food packaging. In this study, we investigated the double coating technique to produce multifunctional, high barrier and heat-sealable biodegradable films. The systems consisted of a web layer, made of poly(lactide) (PLA) and poly(butylene-adipate-co-terephthalate) (PBAT), which was first coated with a poly(vinyl) alcohol based layer, providing high barrier, and then with a second layer of PLA + ethylene-bis-stereamide (EBS) wax (from 0 to 20%), to provide sealability and improve moisture resistance. The films were fully characterized in terms of chemical, thermal, morphological, surface and functional properties. The deposition of the PVOH coating alone, with a thickness of 5 μm, led to a decrease in the oxygen transmission rate from 2200 cm³/m² d bar, for the neat substrate (thickness of 22 μm), to 8.14 cm³/m² d bar (thickness of 27 μm). The deposition of the second PLA layer did not affect the barrier properties but provided heat sealability, with a maximum bonding strength equal to 6.53 N/25 mm. The EBS wax incorporation into the PLA slightly increased the surface hydrophobicity, since the water contact angle passed from 65.4°, for the neat polylactide layer, to 71° for the 20% wax concentration. With respect to the substrate, the double-coated films exhibited increased stiffness, with an elastic modulus ca. three times higher, and a reduced elongation at break, which, however still remained above 75%. Overall, the developed double-coated films exhibited performances comparable to those of the most common synthetic polymer films used in the packaging industry, underlining their suitability for the packaging of sensitive foods with high O₂-barrier requirements.

Antimicrobial PLA-PVA multilayer films containing phenolic compounds

Multilayer materials with good interlayer-adhesion were obtained by thermocompression for laminating an internal poly (vinyl alcohol) (PVA) layer with two external poly (lactic acid) (PLA) layers. Carvacrol or ferulic acid were incorporated into the PVA sheet to obtain active materials. The multilayer films were characterised as to their microstructure, thermal behaviour, tensile and barrier properties. Furthermore, the antimicrobial capacity of the materials was analysed in packaged beef meat samples for 17 days at 5 °C. The laminates exhibited tensile properties close to those of the PLA films, but with enhanced stretchability. Compared to the monolayers, the barrier capacity of multilayers was much improved by combining polyester and PVA layers, which provide the laminate with water vapour and oxygen barrier capacity, respectively. Active multilayers were effective at controlling microbial growth in beef meat during cold storage. Therefore, the materials developed were functionally adequate for food packaging purposes and successfully promoted the meat preservation.

Microfibrillated cellulose reinforced starch/polyvinyl alcohol antimicrobial active films with controlled release behavior of cinnamaldehyde

The starch/polyvinyl alcohol (ST/PVA) films incorporated with cinnamaldehyde (CIN) and microfibrillated cellulose (MFC) were developed. The effect of MFC content on the films' properties was studied. The SEM results showed that MFC promoted compatibility among starch, PVA and CIN. With increased content of MFC, the strength of the films was improved and their flexibility reduced, the films' crystallinity degree and hydrophobicity were improved. The oxygen and water vapor permeability of the films both reduced first and then increased as a whole. The release of CIN from films into the food stimulant (10% ethanol) could be controlled by MFC. When MFC content was between 1% and 7.5%, it decelerated the release of CIN but high MFC content exceeded 10% promoted the release of CIN. It revealed that films containing CIN could inhibit growth of S. putrefaciens. It showed a good prospect of using MFC to develop controlled release active ST/PVA films.

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.

Bioactive Electrospun Fibers of Poly(ε-Caprolactone) Incorporating α-Tocopherol for Food Packaging Applications

Antioxidant activity is an important feature for food contact materials such as packaging, aiming to preserve freshness and retard food spoilage. Common bioactive agents are highly susceptible to various forms of degradation; therefore, protection is required to maintain functionality and bioavailability. Poly(ε-caprolactone) (PCL), a biodegradable GRAS labeled polymer, was used in this study for encapsulation of α-tocopherol antioxidant, a major component of vitamin E, in the form of electrospun fibers. Rheological properties of the fiber forming solutions, which determine the electrospinning behavior, were correlated with the properties of electrospun fibers, e.g., morphology and surface properties. Interactions through hydrogen bonds were evidenced between the two components. These have strong effect on structuration of macromolecular chains, especially at low α-tocopherol amounts, decreasing viscosity and elastic modulus. Intra-molecular interactions in PCL strengthen at high α-tocopherol amounts due to decreased solvation, allowing good structural recovery after cease of mechanical stress. Morphologically homogeneous electrospun fibers were obtained, with ~6 μm average diameter. The obtained fibers were highly hydrophobic, with fast release in 95% ethanol as alternative simulant for fatty foods. This induced good in vitro antioxidant activity and significant in vivo reduction of microbial growth on cheese, as determined by respirometry. Therefore, the electrospun fibers from PCL entrapping α-tocopherol as bioactive agent showed potential use in food packaging materials.

Essential Oils in Livestock: From Health to Food Quality

Using plant essential oils (EOs) contributes to the growing number of natural plants' applications in livestock. Scientific data supporting the efficacy of EOs as anti-inflammatory, antibacterial and antioxidant molecules accumulates over time; however, the cumulative evidence is not always sufficient. EOs antioxidant properties have been investigated mainly from human perspectives. Still, so far, our review is the first to combine the beneficial supporting properties of EOs in a One Health approach and as an animal product quality enhancer, opening new possibilities for their utilization in the livestock and nutrition sectors. We aim to compile the currently available data on the main anti-inflammatory effects of EOs, whether encapsulated or not, with a focus on mammary gland inflammation. We will also review the EOs' antioxidant activities when given in the diet or as a food preservative to counteract oxidative stress. We emphasize EOs' in vitro and in vivo ruminal microbiota and mechanisms of action to promote animal health and performance. Given the concept of DOHaD (Developmental Origin of Health and Diseases), supplementing animals with EOs in early life opens new perspectives in the nutrition sector. However, effective evaluation of the significant safety components is required before extending their use to livestock and veterinary medicine.

Eugenol-Containing Essential Oils Loaded onto Chitosan/Polyvinyl Alcohol Blended Films and Their Ability to Eradicate Staphylococcus aureus or Pseudomonas aeruginosa from Infected Microenvironments

Chronic wounds (CW) create numerous entryways for pathogen invasion and prosperity, further damaging host tissue and hindering its remodeling and repair. Essential oils (EOs) exert quick and efficient antimicrobial (AM) action, unlikely to induce bacterial resistance. Cinnamon leaf and clove oils (CLO and CO) display strong AM activity, namely against Staphylococcus aureus and Pseudomonas aeruginosa. Chitosan (CS) is a natural and biodegradable cationic polysaccharide, also widely known for its AM features. CS and poly (vinyl alcohol) (PVA) films were prepared (ratio 30/70 w/w; 9 wt%) by the solvent casting and phase inversion method. The film's thermal stability and chemical composition data reinforced polymer blending and EO entrapment. Films were supplemented with 1 and 10 wt% of EO in relation to total polymeric mass. The film thickness and degree of swelling (DS) tended to increase with EO content, particularly with 10 wt % CLO (* p < 0.05). UV-visible absorbance scans in the 250-320 cm^-1 region confirmed the successful uptake of CLO and CO into CS/PVA films, particularly with films loaded with 10 wt% EO that contained 5.30/5.32 times more CLO/CO than films supplemented with 1 wt% EO. AM testing revealed that CS films alone were effective against both bacteria and capable of eradicating all P. aeruginosa within the hour (*** p < 0.001). Still, loaded CS/PVA films showed significantly improved AM traits in relation to unloaded films within 2 h of contact. This study is a first proof of concept that CLO and CO can be dispersed into CS/PVA films and show bactericidal effects, particularly against S. aureus, this way paving the way for efficient CW therapeutics.