Developed Chitosan/Oregano Essential Oil Biocomposite Packaging Film Enhanced by Cellulose Nanofibril

A review of advancements in chitosan-essential oil composite films: Better and sustainable food preservation with biodegradable packaging

In response to the environmental pollution caused by non-degradable and non-recyclable plastic packaging films (PPFs) and the resulting health concerns due to the migration of microplastics into food, the development of biodegradable food packaging films has gained great attention. Chitosan has been extensively utilized in the food industry owing to its abundant availability, exceptional biocompatibility, degradability, and antimicrobial properties. Chitosan-essential oil composite films (CEOs) represent a promising avenue to replace conventional PPFs. This review provides an overview of the advancements in CEOs over the past decade, focusing on the effects of essential oils (EOs) on CEOs in terms of antimicrobial activity, antioxidant effect, gas barrier, light barrier, and mechanical properties. It also offers insights into the controlled release of EOs in CEOs and summarizes the application of CEOs in fresh food preservation.

The Extraction and Impact of Essential Oils on Bioactive Films and Food Preservation, with Emphasis on Antioxidant and Antibacterial Activities-A Review

Essential oils, consisting of volatile compounds, are derived from various plant parts and possess antibacterial and antioxidant properties. Certain essential oils are utilized for medicinal purposes and can serve as natural preservatives in food products, replacing synthetic ones. This review describes how essential oils can promote the performance of bioactive films and preserve food through their antioxidant and antibacterial properties. Further, this article emphasizes the antibacterial efficacy of essential oil composite films for food preservation and analyzes their manufacturing processes. These films could be an attractive delivery strategy for improving phenolic stability in foods and the shelf-life of consumable food items. Moreover, this article presents an overview of current knowledge of the extraction of essential oils, their effects on bioactive films and food preservation, as well as the benefits and drawbacks of using them to preserve food products.

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.

Thermal, Morphological and Mechanical Properties of a BioPE Matrix Composite: Case of Shell, Pulp, and Argan Cake as Biofillers

Extrusion and hot compressing molding processes were used to create bio-polyethylene (BioPE) composites reinforced with argan byproducts (shell, pulp, and argan cake) as bio-fillers. The thermal stability of the composites wass analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Dynamical mechanical analysis and rheological testing were used to investigate their mechanical properties. The morphological results showed a good adhesion between the argan and BioPE matrix. More efficient mechanical properties have been distinguished in the case of argan byproduct-based composite. A higher Young's modulus was noted for all the biocomposites compared to pure BioPE. Thermal analysis revealed that the addition of bio-filler to polymer reduced decomposition temperatures. This study provides an ecological alternative for upgrading the valorization of abundant and underutilized Moroccan biomass. Furthermore, the possibility of using argan byproducts in composite manufacturing will help open up new markets for what is currently considered waste.

Long-Term Refrigerated Storage of Beef Using an Active Edible Film Reinforced with Mesoporous Silica Nanoparticles Containing Oregano Essential Oil (Lippia graveolens Kunth)

Beef is a fundamental part of the human diet, but it is highly susceptible to microbiological and physicochemical deterioration which decrease its shelf life. This work aimed to formulate an active edible film (AEF) incorporated with amino-functionalized mesoporous silica nanoparticles (A-MSN) loaded with Mexican oregano (Lippia graveolens Kunth) essential oil (OEO) and to evaluate its effect as a coating on fresh beef quality during refrigerated storage. The AEF was based on amaranth protein isolate (API) and chitosan (CH) (4:1, w/w), to which OEO emulsified or encapsulated in A-MSN was added. The tensile strength (36.91 ± 1.37 MPa), Young's modulus (1354.80 ± 64.6 MPa), and elongation (4.71%) parameters of AEF made it comparable with synthetic films. The antimicrobial activity of AEF against E. coli O157:H7 was improved by adding 9% (w/w) encapsulated OEO, and interactions of glycerol and A-MSN with the polymeric matrix were observed by FT-IR spectroscopy. In fresh beef, after 42 days, AEF reduced the population growth (Log CFU/cm², relative to uncoated fresh beef) of Brochothrix thermosphacta (5.5), Escherichia coli (3.5), Pseudomonas spp. (2.8), and aerobic mesophilic bacteria (6.8). After 21 days, odor acceptability of coated fresh beef was improved, thus, enlarging the shelf life of the beef and demonstrating the preservation capacity of this film.

Life Cycle Assessment and Preliminary Cost Evaluation of a Smart Packaging System

Smart food packaging (SP) is an innovative packaging system that can extend the shelf life of the product and reduce food waste. The objective of the study is the estimation of the environmental and economic sustainability of the overall life cycle of a SP including a chemical sensor able to detect modifications in the concentration of CO2, which is an indicator of food spoilage, and encapsulated oregano essential oil (OEO), capable of inhibiting the microbial growth. For this purpose, a life cycle assessment (LCA), following the ISO 14040 series and ReCiPe methodology, and an economic evaluation of SP, were performed. The environmental footprint (EF) of SP was compared to that of a conventional packaging (CP) in terms of packaging production, use and end of life (EoL) of both the packaging and the contained food product. The results demonstrated that the production of SP burdened by 67% the impact category of climate change. However, when adapting four use and EoL scenarios, namely the CP generates 30% food waste, whereas SP can generate 5% (optimistic scenario), 10% (realistic) or 20% (conservative) waste, SP proved to be environmentally superior in most impact categories.

Antibacterial Gelidium amansii polysaccharide-based edible films containing cyclic adenosine monophosphate for bioactive packaging

A homogeneous polysaccharide (GAP), with a molecular weight of 51.8 kDa, was isolated from edible red seaweed Gelidium amansii. Composition analysis suggested GAP contained 5.31% sulfate and 17.33% 3,6-anhydro-galactose and was mainly composed of galactose. Furthermore, GAP, as a biopolymer matrix, was used to form the composite films with the small biological molecules cytidine-5'-monophosphate (CMP), adenosine-5'-monophosphate (AMP), and cyclic adenosine monophosphate (cAMP). Scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectrum, and X-ray diffraction (XRD) results showed that CMP, AMP, and cAMP interacted with the film substrates and might made films more complex. Notably, the addition of CMP, AMP, and cAMP promoted the light, water vapor, and oxygen barrier ability, surface wettability, mechanical strength, and antimicrobial activity against Gram-negative and -positive bacteria. Finally, GAP-based films composited with cAMP (cAMPF) exhibited the best characteristics were applied to fish packaging and preservation at 4 °C and extended the fish shelf life. All these data suggested the potential value of cAMPF as a functional edible polysaccharide film applied in food industries.

Infectious Inflammatory Processes and the Role of Bioactive Agent Released from Imino-Chitosan Derivatives Experimental and Theoretical Aspects

The paper focuses on the development of a multifractal theoretical model for explaining drug release dynamics (drug release laws and drug release mechanisms of cellular and channel-type) through scale transitions in scale space correlated with experimental data. The mathematical model has been developed for a hydrogel system prepared from chitosan and an antimicrobial aldehyde via covalent imine bonds. The reversible nature of the imine linkage points for a progressive release of the antimicrobial aldehyde is controlled by the reaction equilibrium shifting to the reagents, which in turn is triggered by aldehyde consumption in the inhibition of the microbial growth. The development of the mathematical model considers the release dynamic of the aldehyde in the scale space. Because the release behavior is dictated by the intrinsic properties of the polymer–drug complex system, they were explained in scale space, showing that various drug release dynamics laws can be associated with scale transitions. Moreover, the functionality of a Schrödinger-type differential equation in the same scale space reveals drug release mechanisms of channels and cellular types. These mechanisms are conditioned by the intensity of the polymer–drug interactions. It was demonstrated that the proposed mathematical model confirmed a prolonged release of the aldehyde, respecting the trend established by in vitro release experiments. At the same time, the properties of the hydrogel recommend its application in patients with intrauterine adhesions (IUAs) complicated by chronic endometritis as an alternative to the traditional antibiotics or antifungals.

Cellulose-based antimicrobial films incroporated with ZnO nanopillars on surface as biodegradable and antimicrobial packaging

Biodegradable and antimicrobial films without antibiotics are of great significance for the application associated with food packaging meanwhile minimizing the negative impact on environments. In this work, cellulose-based films with the surface tailor-constructed with ZnO nanopillars (ZnO NPs@Zn²⁺/Cel films) were prepared via chemical crosslinking in conjunction with a hydrothermal process for in-situ growth of ZnO NPs. As a packaging material, ZnO NPs@Zn²⁺/Cel films possess excellent mechanical properties, oxygen and water vapor barrier, food preservation, biodegradability and low Zn²⁺ migration. Moreover, ZnO NPs@Zn²⁺/Cel films show remarkable antimicrobial activity, especially for Staphylococcus aureus (gram-positive bacteria) and Escherichia coli (gram-negative bacteria). The antimicrobial mechanism of ZnO NPs@Zn²⁺/Cel films is studied using the controlled variable method, and results showed that the film without UV pretreatment killed bacterial cells mainly by mechanical rupture, while the film with UV pretreatment killed bacterial cells mainly via the synergistic effect of photocatalytic oxidation and mechanical rupture.

Multifunctional poly(vinyl alcohol) films using cellulose nanocrystals/oregano and cellulose nanocrystals/cinnamon Pickering emulsions: Effect of oil type and concentration

Poly (vinyl alcohol) (PVA) films with high transparency, UV-barrier, antioxidant, and antimicrobial properties were prepared using oregano essential oil (OEO) and cinnamon essential oil (CEO) Pickering emulsions. The effect of Pickering emulsion type and concentration on the PVA film properties was studied. Cellulose nanocrystals (CNCs) were used as a natural stabilizer to prepare OEO and CEO Pickering emulsions. Both emulsions showed spherical droplets with diameters of 155-291 nm, zeta potential of -36.2 to -49.6 mV, minimum inhibition concentration of 6.25-12.5 μL/mL, and inhibition zone of 40-65 mm, depending on oil type. Morphology and FTIR analysis showed that OEO and CEO Pickering emulsions were compatible with the PVA matrix. The UV-transmittance of PVA films decreased from 77.3% to 30.4% and 2.0% without sacrificing the transparency after adding OEO and CEO Pickering emulsions, respectively. Antimicrobial results showed that E. coli was more sensitive to CEO, while S. aureus was sensitive to OEO Pickering emulsion. PVA/CEO film displayed higher properties than PVA/OEO film.

Quantitative study on the performance of CMCS/SA composite fibers by regulating the hydrogen bonding proportions

CMCS/SA composite fibers with various intermolecular hydrogen bonding (inter-MHB) proportions are prepared via a physical blending method.

Effect of Chitosan Coatings with Cinnamon Essential Oil on Postharvest Quality of Mangoes

Mango (Mangifera indica Linn.) is a famous climacteric fruit containing abundant flavor and nutrients in the tropics, but it is prone to decay without suitable postharvest preservation measures. In this study, the chitosan (CH)-cinnamon essential oil (CEO) Pickering emulsion (CH-PE) coating was prepared, with cellulose nanocrystals as the emulsifier, and applied to harvested mangoes at the green stage of maturity. It was compared with a pure CH coating and a CH-CEO emulsion (CH-E) coating, prepared with the emulsifier Tween 80. Results showed that the CH-PE coating had a lower water solubility and water vapor permeability than the other coatings, which was mainly due to electrostatic interactions, and had a better sustained-release performance for CEO than the CH-E coating. During mango storage, the CH-PE coating effectively improved the appearance of mangoes at 25 °C for 12 d by reducing yellowing and dark spots, and delayed water loss. Hardness was maintained and membrane lipid peroxidation was reduced by regulating the activities of pectin methyl esterase, polygalacturonase, and peroxidase. In addition, the nutrient quality was improved by the CH-PE coating, with higher contents of total soluble solid, titratable acid, and ascorbic acid. Therefore, the CH-PE coating is promising to comprehensively maintain the postharvest quality of mangoes, due to its enhanced physical and sustained-release properties.

Improvement of the Antimicrobial Activity of Oregano Oil by Encapsulation in Chitosan-Alginate Nanoparticles

Oregano oil (OrO) possesses well-pronounced antimicrobial properties but its application is limited due to low water solubility and possible instability. The aim of this study was to evaluate the possibility to incorporate OrO in an aqueous dispersion of chitosan—alginate nanoparticles and how this will affect its antimicrobial activity. The encapsulation of OrO was performed by emulsification and consequent electrostatic gelation of both polysaccharides. OrO-loaded nanoparticles (OrO-NP) have small size (320 nm) and negative charge (−25 mV). The data from FTIR spectroscopy and XRD analyses reveal successful encapsulation of the oil into the nanoparticles. The results of thermogravimetry suggest improved thermal stability of the encapsulated oil. The minimal inhibitory concentrations of OrO-NP determined on a panel of Gram-positive and Gram-negative pathogens (ISO 20776-1:2006) are 4–32-fold lower than those of OrO. OrO-NP inhibit the respiratory activity of the bacteria (MTT assay) to a lower extent than OrO; however, the minimal bactericidal concentrations still remain significantly lower. OrO-NP exhibit significantly lower in vitro cytotoxicity than pure OrO on the HaCaT cell line as determined by ISO 10993-5:2009. The irritation test (ISO 10993-10) shows no signs of irritation or edema on the application site. In conclusion, the nanodelivery system of oregano oil possesses strong antimicrobial activity and is promising for development of food additives.

TOCNC-g-PEI nanoparticle encapsulated oregano essential oil for enhancing the antimicrobial activity of cellulose nanofibril packaging films

A nanocellulose-based film with excellent antimicrobial and antioxidant activity was developed by adding Pickering emulsion which was stabilized by functionalized particles. First, TOCNC-g-PEI nanoparticles were prepared by grafting polyethyleneimine (PEI) onto TEMPO-oxidized cellulose nanocrystals (TOCNCs) and used to stabilize oregano essential oil (OEO) Pickering emulsions. The contact angle of TOCNC-g-PEI nanoparticles was 79.7°, and the minimum inhibitory concentration against L.monocytogenes and E.coli was 0.50 mg/mL. Second, the emulsion droplets were stably dispersed in cellulose nanofibril (CNF) suspensions owing to the depletion stability of CNFs. Finally, the films were dried and emulsion droplets formed oil core/CNF shell microcapsules in active CNF films and completely encapsulated OEO in active CNF films. The inhibition rates of the film against L.monocytogenes and E.coli were 97.28% and 97.23%, respectively. The influence of Pickering emulsion on the active CNF films was discussed. The developed active CNF films have promising application in food preservation and active packaging.

Novel 2,3-Dialdehyde Cellulose-Based Films with Photodynamic Inactivation Potency by Incorporating the β-Cyclodextrin/Curcumin Inclusion Complex

Antibacterial packaging film mediated by photodynamic inactivation (PDI) is a new concept in food industry. The objective of this study was to fabricate a green 2,3-dialdehyde cellulose (DAC)-based antimicrobial film with PDI potency by incorporating the β-cyclodextrin/curcumin (β-CD/Cur) complex as a photosensitizer. The PDI-mediated films were characterized by evaluating the surface morphology, chemical structure, light transmittance, mechanical properties, photochemical and thermal stability, and water solubility. The results showed that the DAC-CD/Cur films were soluble in water and mechanically strong with a tensile strength of 63.87 MPa and an elongation break of 1.32%, which was attributed to the formation of hydrogen bonds between DAC and β-CD/Cur molecules. Meanwhile, the composite films possessed a good light transmittance but impeded the penetration of ultraviolet light and efficiently delayed the degradation of curcumin. More importantly, the PDI-mediated films exhibited a broad-spectrum ability to kill Listeria monocytogenes, Vibrio parahaemolyticus, and Shewanella putrefaciens in pure culture. Notably, they also potently inactivated these harmful bacteria on ready-to-eat salmon with a maximum of ∼4 Log CFU/g (99.99%) reduction after 60 min irradiation (13.68 J/cm²). Therefore, the PDI-mediated DAC-CD/Cur films are novel and promising antimicrobial food packaging films in food industry.