Bionanocomposite Films Research Articles

Development of (polyvinylpyrrolidone/chitsoan/citric acid)/(zinc oxide‐nanoparticles) bionanocomposite films and their applications in biodegradation and antimicrobial activity

AbstractBiofilm and bionanocomposite films were synthesized from polyvinylpyrrolidone (PVP), chitosan (CS), citric acid (CA), and zinc oxide‐nanoparticles (ZnO‐NPs). Effects of gamma‐irradiation dose and ZnO‐NPs concentrations; 0, 0.1, 0.3, 0.6, 0.9, 1.2, and 1.5 (wt./wt.)% were studied. Biofilms and bionanocomposite films were characterized by Fourier transform infrared, Raman spectroscopy, transmission electron microscopy, thermal gravimetric analysis, X‐rays diffraction, energy dispersive X‐ray, and mechanical properties to identify structure of biofilm and bionanocomposite films. Swelling (g/g)% and gelation (g/g)% of biofilms were carried out at diverse compositions of PVP to CS of (1/1), (1/2), and (2/1) (v/v). Swelling (g/g)% results of (1/1), (1/2), and (2/1) (v/v) were 116, 110, and 126, respectively. Values of highest and lowest gelation (g/g)% of (1/2) and (2/1) (v/v) are 98.0 ± 1.8 and 85.0 ± 2.6, respectively at 30 kGy. Water vapor transmission rate was studied for films and exposed 3450 ± 4.1 and 185.8 ± 1.2 (kg/m2.day) for open bottle and (PVP/CS/PCA)/(ZnO‐NPs‐1.5), respectively. Values of water solubility (g/g)% were investigated and found 30.21 ± 1.3 and 15.4 ± 2.5 for (PVP/CS/PCA)/(ZnO‐NPs‐0) and (PVP/CS/PCA)/(ZnO‐NPs‐1.5), accordingly. Bionanocomposite films displayed a broad‐spectrum antimicrobial activity against Gram‐negative bacteria and Gram‐positive bacteria. (PVP/CS/PCA)/(ZnO‐NPs‐0.1) showed lowest inhibition zone; 4 ± 0.2, 9 ± 0.5, 19 ± 0.1, and 8 ± 0.3 (mm) compared with (PVP/CS/PCA)/(ZnO‐NPs‐1.5) of highest inhibition zone; 16 ± 0.5, 28 ± 0.2, 33 ± 0.6, and 18 ± 0.3 (mm) for Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus, respectively. Antimicrobial activity increased with increasing ZnO‐NPs concentrations. Biodegradation of biofilms and bionanocomposite films were examined under soil from 0 to120 days. Results of weight loss (g/g)% at 120 days of (PVP/CS/PCA)/(ZnO‐NPs‐0) and (PVP/CS/PCA)/(ZnO‐NPs‐1.5) are 72 ± 4.5 and 47.5 ± 3.8, respectively. Bionanocomposite films were used in food preservation of fresh cherry tomatoes for 30 days and showed goodness. Therefore, these results suggest that the possibility of using bionanocomposite films in food‐packaging applications.Highlights Synthesis of development of (polyvinylpyrrolidone/chitsoan/citric acid)/(zinc oxide‐nanoparticles) bionanocomposite films. Characterization of bionanocomposite films by different techniques. Study of biodegradation of bionanocomposite films. Study of antimicrobial of bionanocomposite films. Usage of bionanocomposite films in cherry tomatoes preservation for 30 days.

Increasing shelf life of millets by developing bio-nanocomposite films (bioplastic) as an alternative to conventional plastic

Millets are considered as most nutritional grain among all. Hence it becomes immense important to prevent and protect such grains from being deteriorated. Spoilage is mostly observed due to bacterial, fungal, or due to some climatic changes. Such spoilage cannot be stopped completely but can be minimized by increasing its shelf life. Development of metal-oxide based bio-nanocomposite film has revolutionized various sectors from food packaging to agriculture. Zinc oxide nanoparticles is considered as GRAS (Generally Recognized As Safe) among all metal-oxides, and hence introduced in various applications. These ZnO NPs can be combined with natural polymer forming bio-nanocomposite films (bioplastic) and therefore used in mulching and food packaging industry. Mulching improves crop yield, requires less water, makes less usage of pesticide, and promote proper growth of plants. Till date, conventional plastic made of polyethylene units are used which causes hazardous effect on environment, hence it become immense important to replace it with a biodegradable and affordable bioplastic. This study involves biosynthesis of ZnO NPs using plant (Cassia fistula) extract and combining it with the natural biopolymer, giving rise to bio-nanocomposite film. These films would show antibacterial activity against pathogen causing spoilage in millets and thus increasing their shelf-life extension. Also, the minimum amount of ZnO NPs required to show antibacterial activity would be determined.

Nanoemulsion-integrated gelatin/bacterial cellulose nanofibril-based multifunctional film: Fabrication, characterization, and application

The current requirements of food safety regulations and the environmental impact stemming from plastic packaging can only be addressed by developing suitable bio-nanocomposite films. Therefore, this study is dedicated to the fabrication of multifunctional film composed of gelatin, bacterial cellulose nanofibrils (BCNF), and black pepper essential oil nanoemulsion (BPEONE) and application for duck meat preservation. BCNF was prepared through ultrasonication of cellulose derived from Komagataeibacter xylinus. BPEONE observed spherical morphology with a diameter ranging from 83.7 to 118 nm. A film matrix containing a higher gelatin proportion than BCNF was more effective in trapping BPEONE. However, increasing the BPEONE fraction showed more surface abrasion and voids in the film morphology. A flexible film with good interaction, crystallinity, and greater thermal stability (421 °C) was developed. Nevertheless, film hydrophobicity (118.89°) declined, resulting in a notable effect on water solubility, swelling, and water vapor permeability. Moreover, the film had improved antibacterial and antioxidant activities, coupled with controlled release characteristics. Consequently, the developed film effectively retarded the lipid oxidation, inhibited microbial growth, and extended the shelf life of duck meat at refrigeration (4 °C) by 3 days, and made the film a promising alternative in the realm of bio-active packaging technology.

Effect of edible film gelatin nano-biocomposite packaging and storage temperature on the store quality of strawberry (Fragaria x ananassa var.duchesne)

An edible film is a type of bioplastic packaging that can be used to package strawberries. Therefore, this study aimed to determine the packaging effect using nanobiocomposite edible film based on gelatin/nanocrystalline cellulose with the addition of antioxidants nanopropolis and storage temperature on the quality and shelf life of strawberries. The strawberries fruit were packed with edible film nanobiocomposite and stored at 5 °C, 10 °C, and 30 °C. The parameters analyzed were water content, Vitamin C, hardness, total dissolved solids, pH, and shelf life. The results showed that the water content ranged from 23.95 to 65.89%w/b at the end of the storage period and was stable at 5 °C and 10 °C. The decrease in water content occurs very quickly at a storage temperature of 30 °C and control. Furthermore, hardness at the end of storage ranged between 0.265 – 0.431 kg/cm² and the fastest decrease in hardness occurred at storage at a temperature of 30 °C. All treatments experienced a decrease in Vitamin C content during storage. The total dissolved solids content at the end of storage was 5.92–12%Brix, with a shelf life ranging from 3 to 21 days of storage, as determined by all treatment parameters. Bionanocomposite edible gelatin film packaging with added nanopropolis can increase shelf life to 21 days of storage. These results showed that bionanocomposite edible film gelatin packaging can increase the shelf life of strawberries.

An emerging sustainable approach for development and characterization of gluten-based nanocomposite films reinforced with starch nanocrystals in conjugation with chitosan

The present study aimed to access the influence of starch nanocrystals (SNCs) with chitosan on functionality of gluten-based bionanocomposite films. Films were reinforced with SNCs (1, 2, and 3 %) along with chitosan (1.5 % and 2.5 %) and characterized for their functional, barrier, morphological, biodegradable, and antimicrobial properties. Results showed that water absorption capacity, solubility, and water vapour transmission rate were significantly (P < 0.05) reduced with the incorporation of SNCs and chitosan, however, highest tensile strength (40.82 MPa) and elongation at break (31.09 %) were observed in 2 % of SNCs and 2.5 % of chitosan. The multifunctional films have high opacity (lightness value >90) confirming with higher thickness (0.17–0.22 mm) of films. X-ray diffraction studies interpret no significant change in A-type crystallinity of the base biopolymer. Field emission scanning electron microscopy showed that bionanocomposite films have fewer surface cracks, less configuration, and crystallinity changes in the composite structure of biopolymer. Fourier transform infrared spectra revealed no differences in the bands, suggesting a positive molecular association confirming the synergistic effect of polyvinyl alcohol (PVOH) and SNCs on gluten in comparison to control film. However, chitosan in films enhanced antioxidant and antimicrobial properties, showing 13.05 mm and 16.66 mm of a zone of inhibition against Staphylococcus aureus and Escherichia coli, respectively. Furthermore, all films showed noticeable degradation >95 % within 55 days under soil conditions. In summary, the addition of SNCs and chitosan produced a stronger/antibacterial film comparable to plastic films for commercialized food packaging industries.

Development of bionanocomposite film based on chia seed mucilage incorporated with ZnO nanoparticles and their application for preserving fresh rainbow trout (Oncorhynchus mykiss) fillets

Development of bionanocomposite film based on chia seed mucilage incorporated with ZnO nanoparticles and their application for preserving fresh rainbow trout (Oncorhynchus mykiss) fillets

Insight into the effect of different nanocellulose types on protein-based bionanocomposite film properties

This paper investigates the effect of five different types of nanocellulose on the properties of protein-based bionanocomposite films (PBBFs) and the mechanism of action. The results show that TEMPO-oxidized nanocellulose (TNC) PBBFs have the smoothest surface structure. This is because some hydroxyl groups in TNC are converted to carboxyl groups, increasing hydrogen bonding and cross-linking with proteins. Bacterial nanocellulose (BNC) PBBFs have the highest crystallinity. Filamentous BNC can form an interlocking network with protein, promoting effective stress transfer in the PBBFs with maximum tensile strength. The PBBFs of lignin nanocellulose (LNC) have superior elasticity due to the presence of lignin, which gives them the greatest creep properties. The PBBFs of cellulose nanocrystals (CNCs) have the largest water contact angle. This is because the small particle size of CNC can be uniformly distributed in the protein matrix. The different types of nanocellulose differ in their microscopic morphology and the number of hydroxyl groups and hydrogen bonding sites on their surfaces. Therefore, there are differences in the spatial distribution and the degree of intermolecular cross-linking of different types of nanocellulose in the protein matrix. This is the main reason for the differences in the material properties of PBBFs.

Waste citrus pectin/garlic bionanohybrids for edible food preservation

Two bioactive molecules derived from citrus peel and garlic (pectin and carbon quantum dot), were used to develop pectin-based edible films for food packaging and coating applications. The interaction between pectin molecules and carbon quantum dots (CDs) resulted in a composite film (CDs/pectin) with improved antioxidant and antibacterial activity, as well as better mechanical properties. The changes brought about by the addition of CDs to the film and their suitability for food packaging were verified through fundamental characterization. The intrinsic fluorescence properties of CDs with pH sensitivity will be further investigated to explore their potential application in food quality detection. Besides, the use of active ingredients from food sources and excellent degradability suggest that the bio-nanocomposite film is a potential edible food packaging material. A formulation based on citrus peel and garlic was used for the surface coating of strawberries to extend their shelf life. The strawberries treated with the active coating did not show any significant signs of decay or dehydration after 5 days. This active packaging coating derived from food ingredients offers a promising natural alternative to conventional materials, with potential applications in extending food product shelf life, promoting human health, and detecting spoilage.

Hybrid green bionanocomposites based on chitosan/starch/gelatin and metallic nanoparticles for biological applications

Multicomponent composites based on natural biopolymers: chitosan, starch and gelatin in two different ratios (0.5:1:1 and 1:1:1) were in situ crosslinked by intermolecular interactions and used as matrices for zinc oxide and magnetite fillers. The bionanocomposite films have been evaluated by spectral and microscopy methods: Fourier-Transform Infrared spectrometry (FT-IR), Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) confirming the electrostatic and hydrogen bonding interactions between the components of the polymeric matrices and the inorganic fillers and the crosslinking process. AFM and SEM images showed a compact, non-porous and homogenous morphology of the hybrid films, proving a good miscibility of the blends. At lower concentrations of embedded filler, the composites were less hardened and more ductile due to the interaction with the polymeric matrix. Increased amounts of inorganic NPs led to the reduced mechanical properties of the prepared materials and increased thermal stability. The bionanocomposites revealed a similar behavior of the dielectric constant with frequency and increased values at higher temperatures. The wettability of the films' surface and the values of the water sorption capacity revealed a slight hydrophilicity of the bionanocomposites as compared with the initial matrices. The biocompatibility, evaluated by means of the surface free energy components and the interfacial tension with blood, and the hemolysis analysis demonstrated that the bionanocomposites possess a low risk of thrombosis, being promising materials for in vivo biomedical applications.

In vitro characterization of bionanocomposites with green silver nanoparticles: A step towards sustainable wound healing materials

AbstractThis study investigated the characterization, antifungal activity, and biocompatibility of green agar/silver and collagen/silver bionanocomposite films for wound healing and cell growth scaffolds. Silver nanoparticles (AgNPs) are known for their antimicrobial properties, but their toxicity and harsh synthesis limit their applications. To address this, green‐synthesized AgNPs G‐AgNPs were incorporated into agar/collagen suspensions at specific concentrations and three different G‐AgNP‐agar and two different G‐AgNP‐col bionanocomposite films were produced. Nanoparticle homogeneity and film quality were characterized through SEM analysis. Mechanical properties were tested using a uniaxial tensile tester, revealing that the bioplastic control samples exhibited UTS of 3.86 MPa compared to 0.60 MPa for collagen, a 6‐fold improvement. Viable cell metabolic activity derived from MTT assay showed that Col‐4%AgNPs and Bio‐30%AgNPs had a 42.9% and 51.6% increase in net metabolic activity respectively compared to control on day 4. Fluorescence microscopy confirmed enhanced cell adhesion and proliferation in G‐AgNP‐incorporated samples. Antifungal properties were evaluated against Cladosporium spores, able to cause severe diseases when in contact with human skins, following ISO 16869:2008 standards. The demonstrated unique properties and tunability of G‐AgNPs bionanocomposites can be employed in a variety of specialties for wound‐healing applications, to improve rate and quality of healing while reducing the risk of infection.

Mechanical, barrier, antibacterial and biodegradable properties of carrageenan/natamycin/graphene hybrid bio nanocomposite film for active antimicrobial food packaging applications

Mechanical, barrier, antibacterial and biodegradable properties of carrageenan/natamycin/graphene hybrid bio nanocomposite film for active antimicrobial food packaging applications

Sodium alginate/Hydroxyapatite/nanocellulose composites: Synthesis and Potentials for bone tissue engineering

Sodium alginate/hydroxyapatite/Nano cellulose (SA/HA/NC) nanocomposite films that possess good biocompatibility for bone tissue engineering are prepared by a simple solution casting. HA is one of the most frequently used bioceramic materials to achieve a high biocompatibility. The bionanocomposite films are analysed by XRD, SEM, EDAX and FTIR studies. XRD confirms the existence of fillers in the polymer. FTIR spectrum shows the different functional modes in the bionanocomposite films. The morphology of fillers and bionanocomposite films are obtained through SEM. The inclusion of NC with different concentrations into the biopolymer film improves the tensile strength. As a result, the loading of 5 wt % of NC and 10 wt% of HA in the SA polymer shows high tensile strength when compared to the pure SA, SA filled with 10 wt% of HA and SA loaded with 10 wt% of HA and inclusion of NC (0.5 and 2.5 wt%). The tensile strength (TS) of bionanocomposite film with 10 wt % of HA is increased by 17%. TS of bionanocomposite film with 0.5 and 2.5 wt% of NC is increased by 177 and 277%, whereas TS of bionanocomposite film loaded 5 wt% of NC is increased by 331%. The swelling, biodegradation and biomineralization tests suggest that this bionanocomposite films are hopeful biomaterials for bone tissue engineering.

Waste fish scale for the preparation of bio-nanocomposite film with novel properties

The aim of this work was to study utilization of waste fish scales to develop a bio-nanocomposite films with corn starch, embedded with ZnO nanoparticles and turmeric as an alternative to synthetic plastics films to pack the food. Four different types of bio-nanocomposite films were prepared using varying amounts of fish scale powder and corn starch. The films were examined for their physical and chemical characteristics, including texture, color, solubility in hot water, tensile strength, organic content, and shape. The films were characterized by FTIR, UV–Vis spectrophotometry and SEM. The developed bio-nanocomposite films demonstrated enhanced water barrier, mechanical and antimicrobial properties. The unique features of the bio-nanocomposite with pH indication property demonstrated their potential usage in food packaging applications. Overall, bio-nanocomposite film showed reduced spoilage and increased shelf-life. The results could be of great relevance for the sustainable utilization of waste fish scale and replacement of synthetic polymers films for food packaging as an alternative with environmental sustainability.

TiO2 loaded on glycidol functionalized poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) nanobiocomposite film for photocatalytic and antibacterial activities

The rapid acceleration of industrialization and urbanization has exacerbated water pollution, which is primarily caused by the presence of highly toxic, non-biodegradable contaminants in industrial waste and effluents. In response to this urgent issue, a novel nanobiocomposite film with titanium dioxide (TiO2) loaded onto a poly(3-hydroxybutyrate-co-18 mol% 3-hydroxyhexanoate) (18PHBH) matrix was developed to serve as an effective dual-function material with photocatalytic and antibacterial properties. Through Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR), Diffuse reflectance ultraviolet-visible (DRUV-Vis), Scanning Electron Microscope (SEM), and X-ray diffraction (XRD) analyses, the physicochemical properties of the TiO2/Gly/18PHBH nanobiocomposite film were exhaustively characterized, revealing effective TiO2 loading and uniform distribution on the film's surface. The film exhibited extraordinary photocatalytic degradation of methylene blue (MB) dye, with the 5TiO2/Gly/18PHBH film demonstrating the greatest efficiency. In addition, antibacterial testing revealed that the film was effective against 99.8 % of Staphylococcus aureus and 96.9 % of Pseudomonas aeruginosa. These results demonstrate the potential of polyhydroxyalkanoate-based films as exceptional nanoparticle matrices and position the 5TiO2/Gly/18PHBH film as a versatile candidate for applications in photocatalysis and antibacterial interventions, providing innovative solutions to critical environmental challenges.

Influence of polyaniline and cellulose nanocrystals on starch biopolymer film for intelligent food packaging

The development of bioplastics is important to reduce the environmental impact of petroleum-based plastic, while intelligent food packaging is essential in reducing food wastage through the accurate indication of food spoilage. In this research, a biopolymer film that is able to detect food spoilage has been fabricated. Starch is the main matrix of the polymer film, while polyaniline (PANI) acts as the sensor component. The biopolymer film is reinforced with cellulose nanocrystal (CNC) extracted from oil palm empty fruit bunches (OPEFB) to enhance the sensor performance. CNC was successfully extracted from OPEFB with a yield and crystallinity index as high as 41% and 83%, respectively. Various characterization methods were employed to characterize the samples, including FT-IR and UV–vis, while TEM was used to scrutinize the morphology of the CNC. The thermal stability of the bio-nanocomposite films was studied through TGA and DSC. The XRD analysis indicates that CNC improves the crystallinity of the film from 18% to 41%. The performance of the bio-nanocomposite films as an ammonia sensor was studied through an ammonia sensitivity test, where the optimum starch/PANI/CNC 6% film has a limit of detection (LOD) and limit of quantification (LOQ) of 52 ppm and 156 ppm, respectively (R2 = 0.9909, RSD = 3.98%). Also, it shows selectivity to ammonia gas only. Therefore, the starch/PANI/CNC biopolymer film has great potential for its application as intelligent food packaging.

Preparation, characterization, and antimicrobial activity of novel chitosan blended almond gum–nanosilica bionanocomposite film for food packaging applications

Abstract Almond gum and varied concentrations of nanosilica (0.2, 0.4, 0.6, 0.8, and 1.0 wt%) were introduced into the chitosan polymer matrix by solution cast method to enrich the characteristics of the bionanocomposite film. The surface topography, thermal stability, crystalline nature, and functional moieties of the synthesized bionanocomposite films were characterized by SEM, TGA, XRD, and FT-IR. The UV–Vis spectrophotometer showed a maximum absorption wavelength for the film containing the highest concentration of nanosilica. Change in properties such as increased tensile strength, elongation and reduced water solubility, and swelling properties were observed for the bionanocomposite film containing 1.0 wt% nanosilica. In addition, the films exhibited excellent inhibition effect against Escherichia coli bacteria and Candida albicans fungus, which were proven by well diffusion assay method. The carrot slices packed in the bionanocomposite film containing the highest amount of nanosilica retained their freshness for a longer period of time, suggesting the film to be an effective and excellent food packaging material.

Fabrication and testing of edible films incorporated with ZnO nanoparticles to enhance the shelf life of bread

On daily basis, large amount of food is spoiled due to various biological, physical, and chemical conditions which cause food-borne diseases. So, it is a great challenge to preserve food to meet the nutritional demands. This research was conducted to increase the shelf life of food items by using edible films embedded with nanoparticles. ZnO nanoparticles were synthesized and characterized by a Particle size analyzer and FTIR. The gelatin and agar films with ZnO NPs were prepared by the solution casting method and characterized by FTIR and SEM. The size of synthesized nanoparticles was around 62–70 nm. FTIR analysis was used to detect the functional groups and the spectra showed peaks at 626 cm−1 and 596 cm−1 which were characteristic peaks of ZnO nanoparticles. The antibacterial activity was high against bacteria. The bread was chose as a food sample to access the effectiveness of bio nanocomposite films for food packaging. Different parameters, like: weight loss, pH determination, microbial analysis, and sensory analysis were checked after regular intervals. The weight loss of bread samples with nanocomposite films packaging was lower than other films at the end of storage. The microbial analysis showed that the packing of samples with nanocomposite films lowered the bacterial growth in them. In conclusion, the prepared nanocomposite films can be recommended as a packaging material for bread samples to increase its quality.

Effect of Dielectric Barrier Discharge Cold Plasma on the Bio-nanocomposite Film and its Potential to Preserve the Quality of Strawberry under Modified Atmosphere Packaging

The present study aimed to investigate the effect of cold plasma on the developed bio-nanocomposite film. A dielectric barrier discharge system was utilized to generate the cold plasma. The films were treated under three different times (5, 10 and 15 min) and the characteristics of the films were evaluated. The cold plasma treatment influence the thermal stability and crystallization of the films. Results showed that the mechanical properties (tensile strength and elongation at break), water vapor permeability, oxygen transmission rate, moisture content and water contact angle characteristics were improved up to 69%, 31%, 34%, 3% and 28%, respectively by cold plasma treatment. In consequence, the average O2 and CO2 concentration of the packed strawberries decreased from 5 and 10% to 4.2% and 5.1%, respectively after 15 days. Finally, the results revealed that the mechanical properties, chemical attributes, physical characteristics and microbial activities of the samples were affected by the treated films. As a result, cold plasma modification can be applied as an effective method to maintain and preservation of fresh fruit.

Unraveling the Potential of Innovative Eco‐friendly Thermoplastic Starch/SEBS‐g‐MA/Graphene Oxide Bionanocomposites

AbstractThe increasing focus on bionanocomposites as environmentally friendly solutions for sustainable applications forms the crux of this study. This study explores the influence of incorporating 2% graphene oxide (GO) on the mechanical and thermal characteristics of blends containing glycerol plasticized thermoplastic starch (TPS) and polystyrene‐block‐poly(ethylene‐ran‐butylene)‐block‐polystyrene‐graft‐maleic anhydride (SEBS‐g‐MA), based matrix films through a solution casting method. Starch is successfully obtained from three varied sources: corn, cassava, and potato, with confirmation via fourier transform infrared spectroscopy (FTIR) and X‐ray diffraction (XRD) analysis. The authors formulate and examine varying proportions of TPS/SEBS‐g‐MA (ranging from 10 to 50 wt.%), focusing on their biodegradability, and find that a 10 wt.% SEBS‐g‐MA concentration yields optimal degradation rates, thus this is kept constant. The bionanocomposite films are probed using techniques such as FTIR, XRD, mechanical strength testing, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), water absorption, and biodegradability studies. These results indicate that GO incorporation results in a robust hydrogen bonding network within the cassava starch‐based bionanocomposite films, enhancing their mechanical strength while decreasing their moisture absorption. Upgraded thermal properties of these films are also evident from the results. Consequently, these materials show promising utility, particularly in the realm of food packaging.

Fabrication of Bio-Nanocomposite Packaging Films with PVA, MMt Clay Nanoparticles, CNCs, and Essential Oils for the Postharvest Preservation of Sapota Fruits.

Sapota is an important climacteric fruit with limited shelf life. A special system must be employed to extend the shelf life of sapota fruits. In the present study, polyvinyl alcohol (PVA) and montmorillonite clay (MMt)-based bio-nanocomposite films (BNFs) were integrated at various concentrations (2%, 4%, 6%, and 8%) into cellulose nanocrystals (CNCs), produced from garlic peels (GPs). The BNF loaded with 8% CNC has a better crystallinity index and mechanical properties than the other concentrations of CNC. Therefore, the 8% CNC-incorporated BNF (BNF-8) was selected for further packaging studies. The combined effect of BNF-8 with ajwain essential oil (AO) and oregano essential oil (OO) vapors and BNF-8 with carbendazim (commercial fungicide-CARB) were investigated. In this study, the BNF-based packagings are categorized into five types, viz: BNF+8% CNC (BNF-8), BNF-8+AO, BNF-8+OO, BNF-8+CARB and the non-packaged fruits (control). The shelf-life duration, antioxidant activity, firmness, decay index, and sensory quality were evaluated in order to identify the effectiveness of packaging treatment on sapota fruits. BNF-8+CARB, BNF-8+AO, and BNF-8+OO packaging extended the shelf life of sapota fruits to up to 12 days and maintained the overall physiochemical parameters and sensory qualities of the fruits. Therefore, the BNF-8+AO and BNF-8+OO packaging materials are appropriate alternatives to commercial fungicides for the preservation of sapota during postharvest storage.