Essential oils (EOs) have received attention in the food industry for developing biopolymer-derived food packaging materials. EOs are an excellent choice to replace petroleum-derived additives in food packaging materials due to their abundance in nature, eco-friendliness, and superior antimicrobial and antioxidant attributes. Thus far, EOs have been used in cellulose-, starch-, chitosan-, and protein-based food packaging materials. Biopolymer-based materials have lower antioxidant and antibacterial properties in comparison with their counterparts, and are not suitable for food packaging applications. Various synthetic-based compounds are being used to improve the antimicrobial and antioxidant properties of biopolymers. However, natural essential oils are sustainable and non-harmful alternatives to synthetic antimicrobial and antioxidant agents for use in biopolymer-derived food packaging materials. The incorporation of EOs into the polymeric matrix affects their physicochemical properties, particularly improving their antimicrobial and antioxidant properties. EOs in the food packaging materials increase the shelf life of the packaged food, inhibit the growth of microorganisms, and provide protection against oxidation. Essential oils also influence other properties, such as tensile, barrier, and optical properties of the biopolymers. This review article gives a detailed overview of the use of EOs in biopolymer-derived food packaging materials. The innovative ways of incorporating of EOs into food packaging materials are also highlighted, and future perspectives are discussed.

Using plant extracts as eco-friendly reducing and stabilizing agents for the synthesis of nanoparticles has gained significant attention in recent years. The current study explores the green synthesis of silver nanoparticles (AgNPs) using the Avena fatua extract and evaluates their antifungal activity against Fusarium oxysporum f.sp. lycopersici (Fol), a fungal plant pathogen. A green and sustainable approach was adopted to synthesize silver nanoparticles before these nanoparticles were employed for anti-fungal activity. The primary indication that AgNPs had formed was performed using UV-vis spectroscopy, where a strong peak at 425 nm indicated the effective formation of these nanoparticles. The indication of important functional groups acting as reducing and stabilizing agents was conducted using the FTIR study. Additionally, morphological studies were executed via SEM and AFM, which assisted with more effectively analyzing AgNPs. Crystalline behavior and size were estimated using powder XRD, and it was found that AgNPs were highly crystalline, and their size ranged from 5 to 25 nm. Synthesized AgNPs exhibited significant antifungal activity against Fol at a concentration of 40 ppm. Furthermore, the inhibitory index confirmed a positive correlation between increasing AgNPs concentration and exposure duration. This study suggests that the combined phytochemical mycotoxic effect of the plant extract and the smaller size of synthesized AgNPs were responsible for the highest penetrating power to inhibit Fol growth. Moreover, this study highlights the potential of using plant extracts as reducing and capping agents for the green synthesis of AgNPs with antifungal properties. The study concludes that A. fatua extract can synthesize antifungal AgNPs as a sustainable approach with robust antifungal efficacy against Fol, underscoring their promising potential for integration into plant protection strategies.

Chronic wounds pose a global challenge, often requiring the use of multifunctional materials that facilitate healing while protecting against infection. The present study develops porous, biodegradable and antibacterial composite hydrogels from chitosan and polyvinyl alcohol (PVA) incorporating honey and aloe vera gel as antimicrobial agents for healing chronic wounds. Hydrogels were prepared by freeze gelation methodology, and further crosslinked with citric acid. FTIR spectra confirmed the presence of characteristic functional groups and showed a reduction in the peak intensities of O–H, N–H, and amide bands in crosslinked hydrogels. Scanning electron micrographs illustrated the clear morphological changes; citric acid crosslinked hydrogels (GG-05, GG-06, GG-08) exhibited more porous, sponge-like structures, with GG-08 achieving the highest porosity, having an average pore size of 21.28 μm. The hydrogel GG-08 demonstrated the greatest water retention capacity, reaching up to 218%, while GG-04 showed the highest degradation of 93% ± 3. The developed hydrogels exhibited better antibacterial properties, especially GG-03, GG-04, GG-07 and GG-08 had excellent activity against Gram-positive Staphylococcus aureus (S. aureus). Similarly, GG-01 and GG-05 showed excellent activities against Gram-negative bacterial strains, i.e. Escherichia coli (E. coli) and Klebsiella pneumonia (K. pneumonia). Anti-hemolytic testing confirmed the biocompatibility and non-toxic nature of hydrogels. The results demonstrated that citric acid addition has significantly improved the antibacterial potential against E. coli and K. pneumonia and also enhanced solution absorption, water retention and moisture content. Overall, these hydrogels demonstrated potential as advanced wound dressings, owing to their better moisture retention, broad-spectrum antibacterial properties and excellent biocompatibility.

Wound infections remain a significant clinical challenge, impeding healing and causing deterioration. Recently, multifunctional hydrogel dressings have gained interest as an effective treatment to treat infections efficiently and enhance wound recovery. The present research is focused on the development of composite hydrogels comprising chitosan (CS), polyvinyl alcohol (PVA), gelatin (GEL) and licorice extract (LE), using the freeze gelation technique. The resulting composite hydrogels of CS/PVA/GEL incorporating LE were characterized by FTIR, XRD and SEM. FTIR analysis confirmed the presence of specific functional groups within the molecules. XRD exhibited the amorphous nature of hydrogels. SEM analysis revealed that increasing the CS ratio in hydrogels created a more porous structure with a smaller pore size. All the hydrogels demonstrated oxygen permeability, which is crucial for the healing process. Among the synthesized hydrogels, MM-2 containing PVA (20 mL) and LE (4 mL) demonstrated superior performance with a water retention capacity of 440% and moisture content of 91%. This exceptional result can be attributed to the higher proportion of PVA and the material’s porous structure, which enhances its hydrophilic properties. The synthesized hydrogels showed good antibacterial potential against three selected strains of bacteria including Bacillus subtilis (B. subtilis), Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The hydrogels’ cytotoxicity levels were assessed through hemolysis assay and the results demonstrated that all hydrogels were non-toxic. The hydrolytic breakdown revealed that the interconnected hydrogels with licorice components exhibited slow degradation, making them more appropriate for long-term wound treatment. Specifically, MM-4 demonstrated a 74% degradation rate and displayed 75% antioxidant activity, indicating its potential effectiveness for chronic wound applications. These characteristics of synthesized CS/PVA/GEL/LE-derived hydrogels suggest their potential use as a promising candidate for wound care applications.

This study developed biodegradable composite coatings and films using chitosan (CS), polyvinyl alcohol (PVA), and gelatin enriched with Rosa rubiginosa extract (RRE) to enhance the shelf life of strawberries.