Antifungal Activities of Different Essential Oils and Their Electrospun Nanofibers against Aspergillus and Penicillium Species Isolated from Bread

Chitosan/alginate/pectin biopolymer-based Nanoemulsions for improving the shelf life of refrigerated chicken breast

This study investigated the use of nanoemulsions and various polymer coatings to enhance the quality and shelf life of chicken breast. This comprehensive study explored the antibacterial activity of essential oils (EOs) against Escherichia coli and Staphylococcus aureus, as well as the characterization of nanoemulsions (Nes) and nanoemulsion-based coatings. The antimicrobial potential of EOs, such as cinnamon, tea tree, jojoba, thyme, and black cumin seed oil, was evaluated against microorganisms, and thyme oil exhibited the highest inhibitory effect, followed by cinnamon and tea tree oil by disk diffusion analysis. The MIC and MBC values of EOs were found between 0.16-2.5 mg/mL and 0.16-5 mg/mL, respectively, while thyme EO resulted in the lowest values showing its antimicrobial potential. Then, the essential oil nanoemulsions (EONe) and their coatings, formulated with thyme oil, alginate, chitosan, and pectin, were successfully characterized. Optical microscope observations confirmed the uniform distribution of droplets in all (EONe), while particle size analysis demonstrated multimodal droplet size distributions. The EONe-chitosan coating showed the highest efficacy in reducing cooking loss, while the EONe-chitosan, EONe-alginate, and EONe-pectin coatings displayed promising outcomes in preserving color stability. Microbial analysis revealed the significant inhibitory effects of the EONe-chitosan coating against mesophilic bacteria, psychrophilic bacteria, and yeasts, leading to an extended shelf life of chicken breast. These results suggest the potential application of thyme oil and NE-based coatings in various industries for antimicrobial activity and quality preservation.

Mesoporous silica nanoparticles: A versatile platform for encapsulation and delivery of essential oils for food applications

Essential oils (EOs) are biologically active and volatile substances that have found widespread applications in the food, cosmetics, and pharmaceutical industries. However, there are some challenges to their commercial utilization due to their high volatility, susceptibility to degradation, and hydrophobicity. In their free form, EOs can quickly evaporate, as well as undergo degradation reactions like oxidation, isomerization, dehydrogenation, or polymerization when exposed to light, heat, or air. Encapsulating EOs within mesoporous silica nanoparticles (MSNPs) could overcome these limitations and thereby broaden their usage. MSNPs may endow protection and slow-release properties to EOs, thereby extending their stability, enhancing their efficacy, and improving their dispersion in aqueous environments. This review explores and compares the design and development of different MSNP-based nanoplatforms to encapsulate, protect, and release EOs. Initially, a brief overview of the various types of available MSNPs, their properties, and their synthesis methods is given to better understand their roles as carriers for EOs. Several encapsulation technologies are then examined, including solvent-based and solvent-free methods. The suitability of each technology for EO encapsulation, as well as its impact on their stability and release, is discussed in detail. Opportunities and challenges for using EO-loaded MSNPs as preservatives, flavor enhancers, and antimicrobial agents in the food industry are then highlighted. Overall, this review aims to bridge a knowledge gap by providing a thorough understanding of EO encapsulation within MSNPs, which should facilitate the application of this technology in the food industry.

Application of chitosan and other biopolymers based edible coatings containing essential oils as green and innovative strategy for preservation of perishable food products: A review

Deterioration of perishable foods due to fungal contamination and lipid peroxidation are the most threatened concern to food industry. Different chemical preservatives have been used to overcome these constrains; however their repetitive use has been cautioned owing to their negative impact after consumption. Therefore, attention has been paid to essential oils (EOs) because of their natural origin and proven antifungal and antioxidant activities. Many EO-based formulations have been in use but their industrial-scale application is still limited, possibly due to its poor solubility, vulnerability towards oxidation, and aroma effect on treated foods. In this sense, active food packaging using biopolymers could be considered as promising approach. The biopolymers can enhance the stability and effectiveness of EOs through controlled release, thus minimizes the deterioration of foods caused by fungal pathogens and oxidation without compromising their sensory properties. This review gives a concise appraisal on latest advances in active food packaging, particularly developed from natural polymers (chitosan, cellulose, cyclodextrins etc.), characteristics of biopolymers, and current status of EOs. Then, different packaging and their effectiveness against fungal pathogens, lipid-oxidation, and sensory properties with recent previous works has been discussed. Finally, effort was made to highlights their safety and commercialization aspects towards market solutions.

Novel Microemulsions with Essential Oils for Environmentally Friendly Cleaning of Copper Cultural Heritage Artifacts

Cleaning represents an important and challenging operation in the conservation of cultural heritage, and at present, a key issue consists in the development of more sustainable, "green" materials and methods to perform it. In the present work, a novel xylene-in-water microemulsion based on nonionic surfactants with low toxicity was obtained, designed as low-impact cleaning agent for metallic historic objects. Phase diagram of the mixtures containing polyoxyethylene-polyoxypropilene triblock copolymer Pluronic P84 and D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) as surfactants, water, ethanol and xylene was studied, and a microemulsion with low surfactant content was selected as suitable cleaning nanosystem. Essential oils (EOs) from thyme and cinnamon leaf were added to the selected microemulsion in order to include other beneficial properties such as anticorrosive and antifungal protection. The microemulsions with or without EOs were characterized by size, size distribution and zeta potential. The cleaning efficacy of the tested microemulsions was assessed based on their ability to remove two types of artificial dirt by using X-ray energy dispersion spectrometry (EDX), scanning electron microscopy (SEM), contact angle measurements and color analysis. Microemulsions exhibit high capacity to remove artificial dirt from model copper coupons in spite of very low content of the organic solvent. Both thyme and cinnamon oil loading microemulsions prove to significantly reduce the corrosion rate of treated metallic plates compared to those of bare copper. The antifungal activity of the novel type of microemulsion was evaluated against Aspergillus niger, reported as main treat in biocorrosion of historic copper artifacts. Application of microemulsion with small amounts of EOs on Cu plates inhibits the growth of fungi, providing a good fungicidal effect.

Encapsulation and delivery systems of cinnamon essential oil for food preservation applications

Food safety threats and deterioration due to the invasion of microorganisms has led to economic losses and food-borne diseases in the food industry; so, development of natural food preservatives is urgently needed when considering the safety of chemically synthesized preservatives. Because of its outstanding antioxidant and antibacterial properties, cinnamon essential oil (CEO) is considered a promising natural preservative. However, CEO's low solubility and easy degradability limits its application in food products. Therefore, some encapsulation and delivery systems have been developed to improve CEO efficiency in food preservation applications. This work discusses the chemical and techno-functional properties of CEO, including its key components and antioxidant/antibacterial properties, and summarizes recent developments on encapsulation and delivery systems for CEO in food preservation applications. Since CEO is currently added to most biopolymeric films/coatings (BFCs) for food preservation, most studies have shown that encapsulation systems can improve the food preservation performance of BFCs containing CEOs. It has been confirmed that various delivery systems could improve the stability and controlled-release properties of CEO, thereby enhancing its ability to extend the shelf life of foods. These encapsulation techniques include spray drying, emulsion systems, complex coacervation (nanoprecipitation), ionic gelation, liposomes, inclusion complexation (cyclodextrins, silica), and electrospinning.

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.