Active Polypropylene-Based Films Incorporating Combined Antioxidants and Antimicrobials: Preparation and Characterization

Electrospun-modified xanthan gum nanofibers enhanced with nisin for food packaging applications

This study investigates developing and characterizing electrospun nanofibers composed of polyvinyl alcohol (PVA) and oxidized xanthan gum (OXG), with nisin as a bioactive agent, for innovative food packaging applications. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) confirmed successful crosslinking between PVA and OXG, along with uniform nisin dispersion within the fibers. The inclusion of OXG increased moisture content (MC) and water solubility (WS) while reducing porosity and water vapor permeability (WVP), demonstrating its role as a crosslinker. Conversely, nisin reduced MC to 25.13 ± 0.93 %, WS to 43.45 ± 4.32 %, and increased porosity to 61.5 ± 4.25 % and WVP to 1.75 ± 0.08 × 103 g/h·m2·Pa. Tensile strength significantly improved with higher nisin concentrations, rising from 10.8 ± 2.35 MPa to 20.31 ± 2.94 MPa, attributed to Schiff base crosslinking. Additionally, nisin-containing nanofibers exhibited enhanced antioxidant properties, increasing radical scavenging activity by 65 %. These findings highlight the potential of PVA/OXG/nisin-based nanofibers to address gaps in food packaging by offering robust mechanical strength, superior barrier properties, and bioactive functionality, paving the way for next-generation packaging solutions that extend shelf life and reduce environmental impact.

Nanocomposites and their application in antimicrobial packaging

The advances in nanocomposites incorporating bioactive substances have the potential to transform the food packaging sector. Different nanofillers have been incorporated into polymeric matrixes to develop nanocomposite materials with improved mechanical, thermal, optical and barrier properties. Nanoclays, nanosilica, carbon nanotubes, nanocellulose, and chitosan/chitin nanoparticles have been successfully included into polymeric films, resulting in packaging materials with advanced characteristics. Nanostructured antimicrobial films have promising applications as active packaging in the food industry. Nanocomposite films containing antimicrobial substances such as essential oils, bacteriocins, antimicrobial enzymes, or metallic nanoparticles have been developed. These active nanocomposites are useful packaging materials to enhance food safety. Nanocomposites are promising materials for use in food packaging applications as practical and safe substitutes to the traditional packaging plastics.

Nanoencapsulation of Chavir (Ferulago angulata) essential oil in chitosan carrier: Investigating physicochemical, morphological, thermal, antimicrobial and release profile of obtained nanoparticles

The essential oil obtained by steam-distillation from Ferulago angulata (FA) was stabilized by ionic-gelation technique within chitosan nanoparticles (CSNPs). The aim of this study was to investigate different properties of CSNPs loaded with FA essential oil (FAEO). GC-MS analysis detected the major components of FAEO as α-pinene (21.85 %), β-ocimene (19.37 %), bornyl acetate (10.50 %) and thymol (6.80 %). Due to presence of these components, FAEO showed stronger antibacterial activity against S. aureus and E. coli with MIC values of 0.45 and 2.12 mg/mL, respectively. Chitosan to FAEO ratio of 1: 1.25 exhibited a maximum encapsulation efficiency (60.20 %) and loading capacity (24.5 %) values. By increasing loading ratio from 1:0 to 1:1.25, mean particle size and polydispersity index were significantly (P < 0.05) increased from 175 to 350 nm and 0.184 to 0.32, respectively, while zeta potential was decreased from +43.5 to +19.2 mV, indicating the physical instability of CSNPs at higher FAEO loading concentrations. SEM observation proved successful formation of spherical CSNPs during the nanoencapsulation of EO. FTIR spectroscopy indicated successful physical entrapment of EO within CSNPs. Differential scanning calorimetry also proved the physical entrapment of FAEO into polymeric matrix of chitosan. XRD exhibited a broad peak at 2θ = 19° - 25° in loaded-CSNPs as indication of successful entrapment of FAEO within CSNPs. Thermogravimetric analysis showed that encapsulated essential oil was decomposed at higher temperature than its free from, indicating the success of encapsulation technique in stabilizing FAEO within CSNPs.

Exploring the Potential of Grape Pomace Extract to Inhibit Thermo-Oxidative Degradation of Sunflower Oil: From Routine Tests to ATR-FTIR Spectroscopy

Exploring new sources of natural antioxidants is of great interest to edible oil producers, in line with the toxicological problems generated by the use of synthetic antioxidants. This study assesses the potential of lyophilized Pinot Noir grape pomace extract (GPE) to enhance the sunflower oil stability against thermo-oxidative damage compared to BHT during a prolonged exposure to convective heat at 185 °C. Oil thermo-oxidation was monitored based on specific indices such as peroxide value (PV), para-anisidine value (p-AV), inhibition of oil oxidation (IO), total oxidation (TOTOX) value, conjugated dienes and trienes (CDs, CTs), but also by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), where absorbance ratios A 3009 cm^-1/A 2922 cm^-1 (RI), A 3009 cm^-1/A 2853 cm^-1 (RII), A 3009 cm^-1/A 1744 cm^-1 (RIII) and RIV = A 1744 cm^-1/A 2922 cm^-1 (RIV) were investigated. GPE showed a significant inhibitory effect on oil thermo-oxidation and this response was concentration-dependent. Substantial decreases in the investigated indices, compared to the control without added antioxidants, were obtained after 4 h and 8 h of heat exposure of the 800 ppm GPE sample: PV (47%; 42%), p-AV (38%; 33%), IO (54%; 46%), TOTOX (41%; 37%), CDs (46%; 39%), CTs (44%; 29%). Oil exposure to heat resulted in changes in RI-RIV attributed to the reduction in the degree of unsaturation, in response to primary and secondary lipid oxidation. FTIR spectroscopy can be used to differentiate untreated and heat-treated oils based on the absorbance ratios. An inhibitory effect close to that of BHT was achieved by 500 ppm GPE, while a dose of 800 ppm provided greater protection against thermo-oxidation. Our results promote GPE as a natural additive to limit the thermo-oxidative damage of plant oils.

Biomass conversion of agricultural waste residues for different applications: a comprehensive review

Agricultural waste residues (agro-waste) are the source of carbohydrates that generally go in vain or remain unused despite their interesting morphological, chemical, and mechanical properties. With rapid urbanization, there is a need to valorize this waste due to limited non-renewable resources. Utilizing agro-waste also prevents the problems like burning and inefficient disposal that otherwise lead to immense pollution worldwide. In addition, conversion of biomass to value-added products like earthen cups, weaving baskets, and bricks is equally beneficial for the rural population as it provides secondary income, creates jobs, and improves rural people's lifestyles. This review paper will discuss an overview of different applications utilizing agro-waste residues. In particular, agro-wastes used as construction material, bio-fertilizers, pulp and paper products, packaging products, tableware, heating applications, biocomposites, nano-cellulosic materials, soil stabilizers, bioplastics, fire-retardant additive, dye removal, and biofuels will be summarized. Finally, several commercially available agro-waste products will also be discussed, emphasizing the circular economy.

Recent advances in biobased and biodegradable polymer nanocomposites, nanoparticles, and natural antioxidants for antibacterial and antioxidant food packaging applications

Inorganic nanoparticles (NPs) and natural antioxidant compounds are an emerging trend in the food industry. Incorporating these substances in biobased and biodegradable matrices as polysaccharides (e.g., starch, cellulose, and chitosan) and proteins has highlighted the potential in active food packaging applications due to more significant antimicrobial, antioxidant, UV blocking, oxygen scavenging, water vapor permeability effects, and low environmental impact. In recent years, the migration of metal NPs and metal oxides in food contact packaging and their toxicological potential have raised concerns about the safety of the nanomaterials. In this review, we provide a comprehensive overview of the main biobased and biodegradable polymer nanocomposites, inorganic NPs, natural antioxidants, and their potential use in active food packaging. The intrinsic properties of NPs and natural antioxidant actives in packaging materials are evaluated to extend shelf-life, safety, and food quality. Toxicological and safety aspects of inorganic NPs are highlighted to understand the current controversy on applying some nanomaterials in food packaging. The synergism of inorganic NPs and plant-derived natural antioxidant actives (e.g., vitamins, polyphenols, and carotenoids) and essential oils (EOs) potentiated the antibacterial and antioxidant properties of biodegradable nanocomposite films. Biodegradable packaging films based on green NPs-this is biosynthesized from plant extracts-showed suitable mechanical and barrier properties and had a lower environmental impact and offered efficient food protection. Furthermore, AgNPs and TiO₂ NPs released metal ions from packaging into contents insufficiently to cause harm to human cells, which could be helpful to understanding critical gaps and provide progress in the packaging field.

Polylactide Films with the Addition of Olive Leaf Extract-Physico-Chemical Characterization

The aim of this work was to obtain and characterize polylactide films (PLA) with the addition of poly(ethylene glycol) (PEG) as a plasticizer and chloroformic olive leaf extract (OLE). The composition of OLE was characterized by LC-MS/MS techniques. The films with the potential for using in the food packaging industry were prepared using a solvent evaporation method. The total content of the phenolic compounds and DPPH radical scavenging assay of all the obtained materials have been tested. Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (FTIR-ATR) allows for determining the molecular structure, while Scanning Electron Microscopy (SEM) indicated differences in the films' surface morphology. Among other crucial properties, mechanical properties, thickness, degree of crystallinity, water vapor permeation rate (WVPR), and color change have also been evaluated. The results showed that OLE contains numerous active substances, including phenolic compounds, and PLA/PEG/OLE films are characterized by improved antioxidant properties. The OLE addition into PLA/PEG increases the material crystallinity, while the WVPR values remain almost unaffected. From these studies, significant insight was gained into the possibility of the application of chloroform as a solvent for both olive leaf extraction and for the preparation of OLE, PLA, and PEG-containing film-forming solutions. Finally, evaporation of the solvent from OLE can be omitted.