Development of antimicrobial packaging materials by incorporation of gallic acid into Ca2+ crosslinking konjac glucomannan/gellan gum films

Konjac glucomannan-based composite materials: Construction, biomedical applications, and prospects

Konjac glucomannan (KGM) as an emerging natural polymer has attracted increasing interests owing to its film-forming properties, excellent gelation, non-toxic characteristics, strong adhesion, good biocompatibility, and easy biodegradability. Benefiting from these superior performances, KGM has been widely applied in the construction of multiple composite materials to further improve their intrinsic performances (e.g., mechanical strength and properties). Up to now, KGM-based composite materials have obtained widespread applications in diverse fields, especially in the field of biomedical. Therefore, a timely review of relevant research progresses is important for promoting the development of KGM-based composite materials. Innovatively, firstly, this review briefly introduced the structure properties and functions of KGMs based on the unique perspective of the biomedical field. Then, the latest advances on the preparation and properties of KGM-based composite materials (i.e., gels, microspheres, films, nanofibers, nanoparticles, etc.) were comprehensively summarized. Finally, the promising applications of KGM-based composite materials in the field of biomedical are comprehensively summarized and discussed, involving drug delivery, wound healing, tissue engineering, antibacterial, tumor treatment, etc. Impressively, the remaining challenges and opportunities in this promising field were put forward. This review can provide a reference for guiding and promoting the design and biomedical applications of KGM-based composites.

Hemicellulose and unlocking potential for sustainable applications in biomedical, packaging, and material sciences: A narrative review

Hemicellulose, a complex polysaccharide abundantly found in plant cell walls, has garnered significant attention for its versatile applications in various fields including biomedical, food packaging, environmental, and material sciences. This review systematically explores the composition, extraction methods, and diverse applications of hemicellulose-derived materials. Various extraction techniques such as organic acid, organic base, enzyme-assisted, and hydrothermal methods are discussed in detail, highlighting their efficacy and potential drawbacks. The applications of hemicellulose encompass biodegradable films, edible coatings, advanced hydrogels, and emulsion stabilizers, each offering unique properties suitable for different industrial needs. Current challenges in hemicellulose research include extraction efficiency, scalability of production processes, and optimization of material properties. Opportunities for future research are outlined, emphasizing the exploration of new applications and interdisciplinary approaches to harness the full potential of hemicellulose. This comprehensive review aims to provide valuable insights for researchers and industry professionals interested in utilizing hemicellulose as a sustainable and functional biomaterial.

Advancements in Gellan Gum-Based Films and Coatings for Active and Intelligent Packaging

Gellan gum (GG) is a natural polysaccharide with a wide range of industrial applications. This review aims to investigate the potential of GG-based films and coatings to act as environmentally friendly substitutes for traditional petrochemical plastics in food packaging. GG-based films and coatings exhibit versatile properties that can be tailored through the incorporation of various substances, such as plant extracts, microorganisms, and nanoparticles. These functional additives enhance properties like the light barrier, antioxidant activity, and antimicrobial capabilities, all of which are essential for extending the shelf-life of perishable food items. The ability to control the release of active compounds, along with the adaptability of GG-based films and coatings to different food products, highlights their effectiveness in preserving quality and inhibiting microbial growth. Furthermore, GG-based composites that incorporate natural pigments can serve as visual indicators for monitoring food freshness. Overall, GG-based composites present a promising avenue for the development of sustainable and innovative food packaging solutions.

Fabrication, Functional Properties, and Potential Applications of Mixed Gellan-Polysaccharide Systems: A Review

Gellan, an anionic heteropolysaccharide synthesized by Sphingomonas elodea, is an excellent gelling agent. However, its poor mechanical strength and high gelling temperature limit its application. Recent studies have reported that combining gellan with other polysaccharides achieves desirable properties for food- and biomaterial-related applications. This review summarizes the fabrication methods, functional properties, and potential applications of gellan-polysaccharide systems. Starch, pectin, xanthan gum, and konjac glucomannan are the most widely used polysaccharides in these composite systems. Heating-cooling and ionic-induced cross-linking approaches have been used in the fabrication of these systems. Composite gels fabricated using gellan and various polysaccharides exhibit different functional properties, possibly because of their distinct molecular interactions. In terms of applications, mixed gellan-polysaccharide systems have been extensively used in texture modification, edible coatings and films, bioactive component delivery, and tissue-engineering applications. Further scientific studies, including structural determinations of mixed systems, optimization of processing methods, and expansion of applications in food-related fields, are needed.

A novel edible solid fat substitute: Preparation of biphasic stabilized bigels based on glyceryl monolaurate and gellan gum

Solid fats contribute to a delicate and pleasant flavor for food, but its excessive intake increases the risk of cardiovascular disease. Bigel is considered a promising solid fat substitute as it significantly reduces fat content while meeting consumer demands for food flavor and a balanced diet. In this study, bigels were prepared by mixing glyceryl monolaurate-based oleogel (10 wt%) and gellan gum-based hydrogel (0.8 wt%) at ratios of 1:3, 1:1, and 3:1. The microscopic results indicated that the oleogel/hydrogel ratios influenced the structure of bigels, forming oil-in-water, bi-continuous, and water-in-oil bigels with the increase of oleogel proportion, respectively. All bigels presented a semi-solid structure dominated by elasticity, and their hardness, gumminess, chewiness, and cohesiveness increased with the enhancement of hydrogel proportion. Among them, the bigels (S25:L75 and S25:H75) prepared with an oleogel/hydrogel ratio of 1:3 showed excellent freeze-thaw stability, maintaining an oil holding capacity of >95 % after three freeze-thaw cycles. Meanwhile, they also presented good oxidative stabilities, where the peroxide values and malondialdehyde contents were below 0.07 g/100 g and 1.5 mg MDA/kg at 12 d, respectively. Therefore, S25:L75 and S25:H75 are expected to be green, low-cost, healthy, and sustainable alternatives to solid fats.

Development of pH-freshness smart label based on gellan gum film incorporated with red cabbage anthocyanins extract and its application in postharvest mushroom

Novel colorimetric films based on gellan gum (GG) containing red cabbage anthocyanins extract (RCAE) were prepared as pH-freshness smart labels for real-time visual detection of mushroom freshness. The GG/RCAE films had excellent pH and ammonia sensitivity. The GG/RCAE-0.2-0.3 films had the highest sensitivity to acetic acid. The SEM micrographs, AFM images, FT-IR and XRD spectra demonstrated that RCAE were successfully combined into the film-forming substrate. The incorporation of RCAE resulted in the increase of thermal stability, opacity and surface hydrophobicity of films. Meanwhile, the GG/RCAE-0.2 film exhibited stronger tensile strength and excellent color stability at 4℃. The color changes of GG/RCAE-0.2 film were visually easier to distinguish during the storage of mushroom. The results showed the GG/RCAE films could be used as pH-freshness smart labels to detect the freshness of fruits and vegetables.

Development of smart packaging film incorporated with sodium alginate-chitosan quaternary ammonium salt nanocomplexes encapsulating anthocyanins for monitoring milk freshness

This study focused on the preparation, functionality, and application of smart food packaging films based on polyvinyl alcohol (PVA) and anthocyanins (ACNs) -loaded sodium alginate-chitosan quaternary ammonium salt (HACC-SA) nanocomplexes. The average encapsulation rate of anthocyanins-loaded nanocomplexes reached 62.51 %, which improved the hydrophobicity and water vapor barrier of the PVA film. FTIR confirmed that the nanocomplexes were immobilized in the PVA film matrix by hydrogen bonding, which improved the mechanical properties of the film. The SEM and XRD results demonstrated that the HACC-SA-ACNs nanocomplexes were uniformly distributed in the film matrix and the crystallinity of PVA was decreased. The P/HACC-SA-ACNs film showed a significant response to buffers of pH 2-13 and high color stability after 21 days of storage compared to the P/ACNs film. Furthermore, the color of the composite film changed from purple to red as the milk freshness decreased during 72 h of milk freshness monitoring, indicating that the P/HACC-SA-ACNs films were suitable and promising for application as smart packaging materials.

Chitosan/oxidized Konjac Glucomannan films incorporated with Zanthoxylum Bungeanum essential oil: A novel approach for extending the shelf life of meat

In this study, a novel edible composite film was prepared by chitosan, konjac glucomannan oxidized with ozone for 60 min (OKGM), and Zanthoxylum Bungeanum essential oil (ZEO). The chitosan/OKGM film was fortified with ZEO to assess the physical properties, structure, antioxidant and antibacterial abilities, and pork preservation systematically. Compared to the control group, the addition of 1 % ZEO increased tensile strength by 18.92 % and decreased water solubility, water vapor permeability, and moisture content by 10.05 %, 6.60 %, and 1.03 %, respectively. However, the treatment with ZEO (1.5 % and 2 %) decreased mechanical properties and increased the water vapor permeability. The ultraviolet barrier, antioxidant, and antibacterial abilities of composite films were enhanced by increasing the ZEO addition. Moreover, the COZ-1 film was used to protect the freshness of pork with slow-release behavior of ZEO. The results showed that addition of ZEO significantly decreased the pH value, total viable count, redness, total volatile basic nitrogen, and thiobarbituric acid and increased the hardness of pork after preservation for 10 days. Therefore, the chitosan/OKGM loaded with ZEO film can potentially be used as food packaging, providing new ideas for the research on active packaging materials.

Addition of konjac glucomannan improves spraying efficiency on fruits and vegetables: Effect of surface hydrophilicity and molecular weight

Biomacromolecules have attracted interest as spraying additives due to their degradability, renewability, and non-toxicity. However, microscopic mechanism of the biomacromolecules regulating the droplet behavior on fruits and vegetables is still unclear. In this study, konjac glucomannan (KGM) was used to improve the spraying efficiency and the fresh-keeping performance of tea polyphenols solution. KGM increased effective spreading ratio on hydrophilic surfaces and retention ratio of the main droplet on hydrophobic surfaces, thus improving spraying efficiency. Computational fluid dynamics and Brown dynamics simulations were implemented to investigate KGM behaviors during droplets colliding on hydrophilic and hydrophobic surfaces. Most KGM molecules extended and then collapsed in gradually weakened shear flow. Meanwhile, on the hydrophobic surface, most KGM molecules were continuously stretched by the unstable flow field. As the KGM extended, the kinetic energy of droplets converted into elastic energy stored in the KGM, promoting the stability of droplets on target surfaces and improving the spraying efficiency. The KGM molecular weight of 3.8 × 105 Da was optimal from the point of energy storage density. This study provides more understanding of the mechanism of biomacromolecules on spraying efficiency and guidance to develop biomass spraying additives for fruit and vegetable preservation.

Exploration of curcumin-incorporated dual anionic alginate-quince seed gum films for transdermal drug delivery

The idea of combining bioextracted polymers for wound healing applications has emerged in hopes of developing highly flexible and mechanically stable hydrogel films with controlled drug delivery, biocompatibility, and high collagen deposition. In the present research, polysaccharide films composed of Alginate and Quince Seed Gum (QSG) were fabricated by ionic crosslinking, and their potential for curcumin delivery and wound healing were examined. In this regard, microstructure, mechanical properties, thermal stability, physiochemical properties, and biocompatibility of films with three different QSG amounts (25 %, 50 %, and 75 %) were studied. Because of the optimum properties of 25 % QSG films like better transparency (Opacity = 6.1 %), higher flexibility (Elongation = 28.9 %), less water solubility (Water solubility = 66.6 %), proper absorbance (Swelling degree = >600 %), and suitable biocompatibility (Cell viability = >85 %), they were used for drug delivery examination. Curcumin administration through films with and without stearic acid modification was investigated. Stearic Acid (SA) modified samples demonstrated superior compatibility between hydrophobic drug and hydrophilic film. Stearic acid-modified film could prolong the curcumin release up to 48 h and showed increased collagen synthesis and TGF-β expression, making it an excellent candidate for transdermal drug delivery and wound healing applications.

Three-Dimensionally Printed Hydrogel Cardiac Patch for Infarct Regeneration Based on Natural Polysaccharides

Myocardial infarction is one of the more common cardiovascular diseases, and remains the leading cause of death, globally. Hydrogels (namely, those using natural polymers) provide a reliable tool for regenerative medicine and have become a promising option for cardiac tissue regeneration due to their hydrophilic character and their structural similarity to the extracellular matrix. Herein, a functional ink based on the natural polysaccharides Gellan gum and Konjac glucomannan has, for the first time, been applied in the production of a 3D printed hydrogel with therapeutic potential, with the goal of being locally implanted in the infarcted area of the heart. Overall, results revealed the excellent printability of the bioink for the development of a stable, porous, biocompatible, and bioactive 3D hydrogel, combining the specific advantages of Gellan gum and Konjac glucomannan with proper mechanical properties, which supports the simplification of the implantation process. In addition, the structure have positive effects on endothelial cells' proliferation and migration that can promote the repair of injured cardiac tissue. The results presented will pave the way for simple, low-cost, and efficient cardiac tissue regeneration using a 3D printed hydrogel cardiac patch with potential for clinical application for myocardial infarction treatment in the near future.

A Systematic Review of Butterfly Pea Flower (Clitoria ternatea L.): Extraction and Application as a Food Freshness pH-Indicator for Polymer-Based Intelligent Packaging

The butterfly pea flower (Clitoria ternatea L.) (BPF) has a high anthocyanin content, which can be incorporated into polymer-based films to produce intelligent packaging for real-time food freshness indicators. The objective of this work was to systematically review the polymer characteristics used as BPF extract carriers and their application on various food products as intelligent packaging systems. This systematic review was developed based on scientific reports accessible on the databases provided by PSAS, UPM, and Google Scholar between 2010 and 2023. It covers the morphology, anthocyanin extraction, and applications of anthocyanin-rich colourants from butterfly pea flower (BPF) and as pH indicators in intelligent packaging systems. Probe ultrasonication extraction was successfully employed to extract a higher yield, which showed a 246.48% better extraction of anthocyanins from BPFs for food applications. In comparison to anthocyanins from other natural sources, BPFs have a major benefit in food packaging due to their unique colour spectrum throughout a wide range of pH values. Several studies reported that the immobilisation of BPF in different polymeric film matrixes could affect their physicochemical properties, but they could still effectively monitor the quality of perishable food in real-time. In conclusion, the development of intelligent films employing BPF's anthocyanins is a potential strategy for the future of food packaging systems.

Structure, Merits, Gel Formation, Gel Preparation and Functions of Konjac Glucomannan and Its Application in Aquatic Food Preservation

Konjac glucomannan (KGM) is a natural polysaccharide extracted from konjac tubers that has a topological structure composed of glucose and mannose. KGM can be used as a gel carrier to load active molecules in food preservation. The three-dimensional gel network structure based on KGM provides good protection for the loaded active molecules and allows for sustained release, thus enhancing the antioxidant and antimicrobial activities of these molecules. KGM loaded with various active molecules has been used in aquatic foods preservation, with great potential for different food preservation applications. This review summarizes recent advances in KGM, including: (i) structural characterization, (ii) the formation mechanism, (iii) preparation methods, (iv) functional properties and (v) the preservation of aquatic food.

The properties of pH-responsive gelatin-based intelligent film as affected by ultrasound power and purple cabbage anthocyanin dose

A pH-sensitive intelligent film was prepared using gelatin as base substrate and purple cabbage anthocyanins (PCA) as indicator with the aid of ultrasound. Fourier transforms infrared and X-ray diffraction analysis showed that 600 W ultrasound brought changes to characteristic bands of gelatin and PCA, and flattened diffraction peak around 2θ = 20°. Film prepared with 600 W ultrasound exhibited high tensile strength and elongation at break and showed high transition temperature and surface hydrophobicity by differential scanning calorimetry and contact angle analysis. The incorporation of <0.35 % PCA had no effect on mechanical properties of films, but it improved the antioxidative activity. Films with 0.14 %, 0.21 % and 0.28 % PCA suggested pronounced color difference at pH 5-8, in accordance with the sharp ΔE difference. Films with 0.28 % PCA was applied for monitoring chilled-stored fish quality. It showed visible color change from pink to atrovirens during storage. The difference of ΔE at various days was ≥5 and ΔE highly correlated with total volatile basic nitrogen. Therefore, gelatin along with PCA under appropriate ultrasound treatment could prepare intelligent film to preserve and monitor the quality of chilled-stored fish.

Preparation and Characterization of Aronia Melanocarpa/Gellan Gum/Pea Protein/Chitosan Bilayer Films

In this study, pH-sensitive bilayer hydrogel films with different AM contents (0.00%, 0.50%, 1.00%, 1.50%, 2.00% and 2.50%) were constructed. The films took AM/GG hydrogel as the inner layer structure and a pea protein (PP)/chitosan (CS) composite system as the outer structure. Film formation and the effect of AM were clarified through the detection and analysis of mechanical properties, microstructure, pH sensitivity and fresh-keeping ability. Results showed that AM exhibited good compatibility with each substance in the composite film, which were evenly dispersed in the system. The addition of AM significantly improved the water content, tensile strength, elongation at break, puncture resistance, oil resistance and water resistance of the composite films. The antioxidant activity, pH sensitivity and fresh-keeping effect of the composite film on fresh pork were remarkably enhanced. Moreover, it was found that the composite film containing AM effectively inhibited the production of total volatile base nitrogen (TVN) in fresh pork and significantly reduced the weight loss of fresh pork due to water loss during storage. Therefore, the functional properties revealed that AM was more positive to the comprehensive performance of films, and the AM-GG/PP-CS bilayer film containing AM exhibited strong potential for use in food preservation and packaging as a food freshness indicator to test food quality changes in storage.

Scalable super hygroscopic polymer films for sustainable moisture harvesting in arid environments

Extracting ubiquitous atmospheric water is a sustainable strategy to enable decentralized access to safely managed water but remains challenging due to its limited daily water output at low relative humidity (≤30% RH). Here, we report super hygroscopic polymer films (SHPFs) composed of renewable biomasses and hygroscopic salt, exhibiting high water uptake of 0.64–0.96 g g⁻¹ at 15–30% RH. Konjac glucomannan facilitates the highly porous structures with enlarged air-polymer interfaces for active moisture capture and water vapor transport. Thermoresponsive hydroxypropyl cellulose enables phase transition at a low temperature to assist the release of collected water via hydrophobic interactions. With rapid sorption-desorption kinetics, SHPFs operate 14–24 cycles per day in arid environments, equivalent to a water yield of 5.8–13.3 L kg⁻¹. Synthesized via a simple casting method using sustainable raw materials, SHPFs highlight the potential for low-cost and scalable atmospheric water harvesting technology to mitigate the global water crisis.

Extracting atmospheric water is a sustainable strategy to enable decentralized access to safely managed water but remains impractical due to its limited daily water output at low relative humidity. Here, the authors demonstrate a hygroscopic polymer composed of renewable biomass which allows high water uptake at low relative humidity

A Comprehensive Review of the Development of Carbohydrate Macromolecules and Copper Oxide Nanocomposite Films in Food Nanopackaging

Background. Food nanopackaging helps maintain food quality against physical, chemical, and storage instability factors. Copper oxide nanoparticles (CuONPs) can improve biopolymers’ mechanical features and barrier properties. This will lead to antimicrobial and antioxidant activities in food packaging to extend the shelf life. Scope and Approach. Edible coatings based on carbohydrate biopolymers have improved the quality of packaging. Several studies have addressed the role of carbohydrate biopolymers and incorporated nanoparticles to enhance food packets’ quality as active nanopackaging. Combined with nanoparticles, these biopolymers create film coatings with an excellent barrier property against transmissions of gases such as O2 and CO2. Key Findings and Conclusions. This review describes the CuO-biopolymer composites, including chitosan, agar, cellulose, carboxymethylcellulose, cellulose nanowhiskers, carrageenan, alginate, starch, and polylactic acid, as food packaging films. Here, we reviewed different fabrication techniques of CuO biocomposites and the impact of CuONPs on the physical, mechanical, barrier, thermal stability, antioxidant, and antimicrobial properties of carbohydrate-based films.

A pH-intelligent response fish packaging film: Konjac glucomannan/carboxymethyl cellulose/blackcurrant anthocyanin antibacterial composite film

Blackcurrant anthocyanins (BCA) can be used to improve the structure and properties of konjac glucomannan (KGM)/carboxymethyl cellulose (CMC) composite film. In this study, the microstructure of the KGM/CMC/BCA composite film was evaluated. The results show that BCA is uniformly dispersed in the KC matrix, which changes the mechanical properties of the film (tensile strength (TS): 55.00 → 38.44 MPa and elongation at break (EB): 8.60 → 3.67%) and barrier properties (water vapor permeability (WVP): 0.67 → 2.53 g·mm/m² day kPa). With the addition of BCA (0.05, 0.15, 0.20 wt%), the composite film exhibits higher thermal stability. Among them, 0.15 wt% has the best thermal stability. The composite film also shows the antioxidant and antibacterial properties of BCA, and has an inhibitory effect on food-borne pathogens. The composite film will show different colors in different buffers, which can be observed with the naked eye. Therefore, KGM/CMC/BCA film can be applied to smart food packaging to realize real-time monitoring of meat product quality.

Recent insights into carrageenan-based bio-nanocomposite polymers in food applications: A review

Nanotechnology has proven as progressive technology that enables to contribute, develop several effective and sustainable changes in food products. Incorporating nanomaterials like TiO₂, SiO₂, Halloysite nano clay, Copper sulfide, Bentonite nano clay, in carrageenan to develop innovative packaging materials with augmented mechanical and antimicrobial properties along with moisture and gas barrier properties that can produce safe and healthy foods. Intervention of carrageenan-based bio-nanocomposites as food packaging constituents has shown promising results in increasing the shelf stability and food quality by arresting the microbial growth. Nanomaterials can be incorporated within the carrageenan for developing active packaging systems for continuous protection of food products under different storage environments from farm to the fork to ensure quality and safety of foods. Carrageenan based bio nanocomposite packaging materials can be helpful to reduce the environmental concerns due to their high biodegradability index. This review gives insight about the current trends in the applications of carrageenan-based bio nanocomposites for different food packaging applications.

An overview of functional genomics and relevance of glycosyltransferases in exopolysaccharide production by lactic acid bacteria

There are many reports on exopolysaccharides of lactic acid bacteria (LAB EPS) such as isolation, production and applications. The LAB EPS have been proved to exhibit significantly improved texture and rheological properties in order to prevent syneresis of fermented foods. Furthermore, they are known to have many biological properties such as mouthwatering flavors, antioxidant activity, cholesterol lowering and antimicrobial activities. Considering their GRAS status, LAB EPS need to be explored for better titre and improved biological properties, where strain improvement by genetic engineering has a major role for making tailor-made EPS. The genetic overview of the EPS production by LAB is an auxiliary area of interest as the process and the biosynthetic pathway involves numerous genes and their proteins. Among them Glycosyltransferases (gtfs) are the key enzymes involved in EPS biosynthesis. Current knowledge of gtfs of LAB and its manipulation is limited. The present review spotlights the importance of glycosyltransferases and their specific role on the biosynthesis of LAB EPS and addresses the functionality and applicability of these enzymes and their products. It enfold the available literature including some patents in recent past to underline the fact that glycosyltransferases are un-reluctantly the key proteins involved in the EPS biosynthesis.

Enhanced antimicrobial activity of konjac glucomannan nanocomposite films for food packaging

This paper aims at providing a new strategy for developing konjac glucomannan-based antibacterial films with excellent performances. Here, novel nanocomposite films based on photodynamic and photothermal synergism strategy were developed by incorporating graphite carbon nitride nanosheets/MoS₂ nanodots (CNMo) into konjac glucomannan (KGM) matrix. Scanning electron microscope, transmission electron microscope, high resolution transmission, high angle annular dark field and element mapping confirmed the successful fabrication of CNMo. The steady and dynamic rheological behavior as well as the good stability of film-forming solution showed that the intermolecular hydrogen bonding was formed. The influences of CNMo content on the structural, mechanical and thermal properties as well as hydrophobicity of KGM films were investigated. This film has a broad-spectrum antibacterial activity. It could prolong the shelf life of cherry tomatoes. Moreover, hemolysis and cells experiment confirm that this film is safe. This strategy is expected to broaden the application of antibacterial packaging.

Dihydromyricetin incorporated active films based on konjac glucomannan and gellan gum

Active composite films were developed by incorporating different concentration of dihydromyricetin (DMY) into konjac glucomannan (KGM)/gellan gum (GG) matrix. Physicochemical, mechanical, released behaviour, antioxidant and antimicrobial properties of composite films were investigated. The results from the Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) indicated that DMY which well-dispersed in the KGM/GG matrix interacted with matrix through hydrogen bonds. The obtained films presented predominant thermostability, good water resistance property, excellent ultraviolet light barrier ability and sustained controlled release behaviour. In particular, the incorporation of DMY remarkably enhanced the antioxidant and antimicrobial activities of the films. Overall, the fabricated KGM/GG-DMY composite films have a promising application in the fields of food packaging.

A novel glucomannan incorporated functionalized carbon nanotube films: Synthesis, characterization and antimicrobial activity

A novel nanocomposite film was developed by incorporating functionalized carbon nanotube (PCNT) and gallic acid (GA) into carboxymethyl konjac glucomannan (CKGM) and gelatin (GL) matrix. The influences of the PCNT content on the structural, morphological, mechanical, barrier, thermal and antimicrobial properties of CKGM/GL nanocomposite film were discussed. The structure of PCNT@CKGM/GL nanocomposite film was characterized by FT-IR, SEM, and AFM. The crystal structure and thermal ability of the film were generated by XRD and TGA-DTG. The analyses of FT-IR revealed that the amide linkage and strong hydrogen bonding were formed between CKGM, GL, and PCNT. Moreover, the characterization of mechanical properties, moisture barrier, and antimicrobial activities indicated the benefits of adding PCNT into CKGM/GL films. The results suggested that the PCNT@CKGM/GL films exhibited antimicrobial activity against Staphylococcus aureus and Escherichia coli. Therefore, such antimicrobial nanocomposite films have the potential of maintaining the quality and prolong the shelf life of food products.

Modification of Collagen/Gelatin/Hydroxyethyl Cellulose-Based Materials by Addition of Herbal Extract-Loaded Microspheres Made from Gellan Gum and Xanthan Gum

Because consumers are nowadays focused on their health and appearance, natural ingredients and their novel delivery systems are one of the most developing fields of pharmacy, medicine, and cosmetics. The main goal of this study was to design, prepare, and characterize composite materials obtained by incorporation of microspheres into the porous polymer materials consisting of collagen, gelatin, and hydroxyethyl cellulose. Microspheres, based on gellan gum and xanthan gum with encapsulated Calendula officinalis flower extract, were produced by two methods: extrusion and emulsification. The release profile of the extract from both types of microspheres was compared. Then, obtained microparticles were incorporated into polymeric materials with a porous structure. This modification had an influence on porosity, density, swelling properties, mechanical properties, and stability of materials. Besides, in vitro tests were performed using mouse fibroblasts. Cell viability was assessed with the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The obtained materials, especially with microspheres prepared by emulsion method, can be potentially helpful when designing cosmetic forms because they were made from safely for skin ingredients used in this industry and the herbal extract was successfully encapsulated into microparticles.

Effect of a multifunctional edible coating based on cassava starch on the shelf life of Andean blackberry

The blackberry is a fragile fruit with a high degree of decomposition, which limits its shelf life. The effect of an edible coating (EC) based on cassava starch, whey protein, beeswax, chitosan, glycerol, stearic acid, and glacial acetic acid on the shelf life of fruit stored at 4 °C was evaluated. The physical, chemical, physical, microbiological, and sensorial quality was evaluated, comparing with a fresh control fruit. The EC had a positive effect on the physicochemical and sensorial properties (mainly in texture, flavor, and aromas), due to the reduction of physiological processes, whereas the color changes are mainly due to anthocyanin losses. After 10 days of storage, weight losses were 39.6% lower and firmness was 81.4% higher; while chitosan reduced the mold and yeast count. The EC increased the useful life of the Andean blackberries by 100%.

Evaluation of multifunctional properties of gallic acid crosslinked Poly (vinyl alcohol)/Tragacanth Gum blend films for food packaging applications

The natural polymer Tragacanth Gum is less explored as a supporting matrix, there are very less studies conducted using this polymer in literature. So the present study aims to explore the consequences of different weight percent (wt.%) of gallic acid (GA) on physicochemical properties of Poly (vinyl alcohol)/Tragacanth Gum blend films. The incorporation of GA resulted in more strengthened but less flexible films as confirmed by tensile tests. DSC studies confirmed the miscibility of composite films in the given composition range and TGA studies revealed increased thermal stability. The morphological studies revealed a homogeneous distribution of GA at lower wt.% in the blend system. X-Ray Diffraction study depicted; the added GA lost crystalline structure after incorporating it into the blend. The Water Vapor Transmission Rate (WVTR) was improved after the incorporation of GA into the blend system. Overall migration studies revealed the limited release of GA from the matrix into food simulants. Soil degradation rate increased as the wt.% of GA increased. The composite films presented strong antioxidant activity; therefore, prepared composite films could be used as an alternative to current packaging materials.