Advances in sustainable food packaging applications of chitosan/polyvinyl alcohol blend films.

Researchers are addressing environmental concerns related to petroleum-based plastic packaging by exploring biopolymers from natural sources, chemical synthesis, and microbial fermentation. Despite the potential of individual biopolymers, they often exhibit limitations like low water resistance and poor mechanical properties. Blending polymers emerges as a promising strategy to overcome these challenges, creating films with enhanced performance. This review focuses on recent advancements in chitosan/polyvinyl alcohol (PVA) blend food packaging films. It covers molecular structure, properties, strategies for performance improvement, and applications in food preservation. The blend's excellent compatibility and intermolecular interactions make it a promising candidate for biodegradable films. Future research should explore large-scale thermoplastic technologies and investigate the incorporation of additives like natural extracts and nanoparticles to enhance film properties. Chitosan/PVA blend films offer a sustainable alternative to petroleum-based plastic packaging, with potential applications in practical food preservation.

Oscillatory rheometry for elucidating the influence of non-network biopolymer aggregation on pectin-gelatin composite gels.

Gel networks formed from biopolymers have intrigued rheological interest, especially in the food industry. Despite ubiquitous non-network biopolymer aggregation in real gel food systems, its fundamental rheological implications remain less understood. This study addresses this by preparing pectin-gelatin composite gels with dispersed or aggregated biopolymers and comparatively analyzing viscoelastic responses using rheometry. Subtle discrepancies in non-network biopolymer states were revealed through oscillatory shearing at different frequencies and amplitudes. Biopolymer aggregation in the network notably influenced loss tangent frequency dependency, particularly at high frequencies, elevating I3/I1 values and sensitizing the yield point. Non-network biopolymers weakened Payne effects and gel non-linearity. A combination of strain stiffening and shear thinning nonlinear responses characterized prepared gel systems. Aggregation of pectin and gelatin enhanced shear thinning, while strain stiffening was notable in highly aggregated pectin cases. This study enhances understanding of the link between non-network structural complexity and viscoelastic properties in oscillatory rheometry of food gels.

The General Composition of Polyhydroxyalkanoates and Factors that Influence their Production and Biosynthesis.

Polyhydroxyalkanoates (PHAs) have been a current research topic for many years. PHAs are biopolymers produced by bacteria under unfavorable growth conditions. They are biomaterials that exhibit a variety of properties, including biocompatibility, biodegradability, and high mechanical strength, making them suitable for future applications. This review aimed to provide general information on PHAs, such as their structure, classification, and parameters that affect the production process. In addition, the most commonly used bacterial strains that produce PHAs are highlighted, and details are provided on the type of carbon source used and how to optimize the parameters for bioprocesses. PHAs present a challenge to researchers because a variety of parameters affect biosynthesis, including the variety of carbon sources, bacterial strains, and culture media. Nevertheless, PHAs represent an opportunity to replace plastics, because they can be produced quickly and at a relatively low cost. With growing environmental concerns and declining oil reserves, polyhydroxyalkanoates are a potential replacement for nonbiodegradable polymers. Therefore, the study of PHA production remains a hot topic, as many substrates can be used as carbon sources. Both researchers and industry are interested in facilitating the production, commercialization, and application of PHAs as potential replacements for nonbiodegradable polymers. The fact that they are biocompatible, environmentally biodegradable, and adaptable makes PHAs one of the most important materials available in the market. They are preferred in various industries, such as agriculture (for bioremediation of oil-polluted sites, minimizing the toxicity of pollutants, and environmental impact) or medicine (as medical devices). The various bioprocess technologies mentioned earlier will be further investigated, such as the carbon source (to obtain a biopolymer with the lowest possible cost, such as glucose, various fatty acids, and especially renewable sources), pretreatment of the substrate (to increase the availability of the carbon source), and supplementation of the growth environment with different substances and minerals). Consequently, the study of PHA production remains a current topic because many substrates can be used as carbon sources. Obtaining PHA from renewable substrates (waste oil, coffee grounds, plant husks, etc.) contributes significantly to reducing PHA costs. Therefore, in this review, pure bacterial cultures (Bacillus megaterium, Ralstonia eutropha, Cupriavidus necator, and Pseudomonas putida) have been investigated for their potential to utilize by-products as cheap feedstocks. The advantage of these bioprocesses is that a significant amount of PHA can be obtained using renewable carbon sources. The main disadvantage is that the chemical structure of the obtained biopolymer cannot be determined in advance, as is the case with bioprocesses using a conventional carbon source. Polyhydroxyalkanoates are materials that can be used in many fields, such as the medical field (skin grafts, implantable medical devices, scaffolds, drug-controlled release devices), agriculture (for polluted water cleaning), cosmetics and food (biodegradable packaging, gentle biosurfactants with suitable skin for cosmetics), and industry (production of biodegradable biopolymers that replace conventional plastic). Nonetheless, PHA biopolymers continue to be researched and improved and play an important role in various industrial sectors. The properties of this material allow its use as a biodegradable material in the cosmetics industry (for packaging), in the production of biodegradable plastics, or in biomedical engineering, as various prostheses or implantable scaffolds.

Packaging films based on biopolymers from seafood processing wastes: Preparation, properties, and their applications for shelf-life extension of seafoods-A comprehensive review.

Biopolymers derived from seafood processing byproducts are used to prepare active and biodegradable films as the packaging of food products. These films possess bioactivities to enhance the shelf life of packed foods by proactively releasing antimicrobial/antioxidative agents into the foods and providing sufficient barrier properties. Seafood processing byproducts are an eminent source of valuable compounds, including biopolymers and bioactive compounds. These biopolymers, including collagen, gelatin, chitosan, and muscle proteins, could be used to prepare robust and sustainable food packaging with some antimicrobial agents or antioxidants, for example, plant extracts rich in polyphenols or essential oils. These active packaging are not only biodegradable but also prevent the deterioration of packed foods caused by spoilage microorganisms as well as chemical deterioration. Seafood discards have a promising benefit for the development of environmentally friendly food packaging systems via the appropriate preparation methods or techniques. Therefore, the green packaging from seafood leftover can be better exploited and replace the synthetic counterpart.

Multifaceted roles of pollen in the management of cancer.

Oral drug delivery of microparticles demonstrates shortcomings like aggregation, decreased loading capacity and batch-to-batch variation, which limits its scale-up. Later, porous structures gained attention because of their large surface-to-volume ratio, high loading capacity and ability to carry biomacromolecules, which undergo degradation in GIT. But there are pitfalls like non-uniform particle size distribution, the impact of porogen properties, and harsh chemicals. To circumvent these drawbacks, natural carriers like pollen are explored in drug delivery, which withstands harsh environments. This property helps to subdue the acid-sensitive drug in GIT. It shows uniform particle size distribution within the species. On the other side, they contain phytoconstituents like flavonoids and polysaccharides, which possess various pharmacological applications. Therefore, pollen has the capability as a carrier system and therapeutic agent. This review focuses on pollen's microstructure, composition and utility in cancer management. The extraction strategies, characterisation techniques and chemical structure of sporopollenin exine capsule, its use in the oral delivery of antineoplastic drugs, and emerging cancer treatments like photothermal therapy, immunotherapy and microrobots have been highlighted. We have mentioned a note on the anticancer activity of pollen extract. Further, we have summarised the regulatory perspective, bottlenecks and way forward associated with pollen.

Modification of palm fiber with chitosan-AESO blend coating.

Natural fibers are available as an essential substitute for synthetic fiber in many applications. However, the sensitivity of Chinese Windmill Palm or Trachycarpus Fortune Fiber (TFF) to water causes low interfacial bonding between the matrix and the fiber and at the end reduces the mechanical properties of the composite product. Alkaline treatment improves mechanical properties and does not affect water absorption. Hence, additional treatment in the coating is required. This study uses alkaline treatment and coating modification using blended chitosan and Acrylated Epoxidized Soybean Oil (AESO). Blend coating between AESO and chitosan is performed to increase water absorption and mechanical properties. TFF water resistance improved significantly after the coating, with water absorption of the alkaline/blend coating-TFF of 3.98 % ± 0.52 and swell ability of 3.156 % ± 0.17. This indicated that blend coating had formed a cross-link of fiber and matrix after alkalization. Thus, the single fiber tensile strength increased due to the alkaline treatment, and water absorption decreased due to the coating. The combination of alkaline treatment and blend coating on TFF brings excellent properties, as shown by the increase in tensile strength in both single fiber test and composite.

Commercialization potential of agro-based polyhydroxyalkanoates biorefinery: A technical perspective on advances and critical barriers.

The exponential increase in the use and careless discard of synthetic plastics has created an alarming concern over the environmental health due to the detrimental effects of petroleum based synthetic polymeric compounds. Piling up of these plastic commodities on various ecological niches and entry of their fragmented parts into soil and water has clearly affected the quality of these ecosystems in the past few decades. Among the many constructive strategies developed to tackle this global issue, use of biopolymers like polyhydroxyalkanoates as sustainable alternatives for synthetic plastics has gained momentum. Despite their excellent material properties and significant biodegradability, polyhydroxyalkanoates still fails to compete with their synthetic counterparts majorly due to the high cost associated with their production and purification thereby limiting their commercialization. Usage of renewable feedstocks as substrates for polyhydroxyalkanoates production has been the thrust area of research to attain the sustainability tag. This review work attempts to provide insights about the recent developments in the production of polyhydroxyalkanoates using renewable feedstock along with various pretreatment methods used for substrate preparation for polyhydroxyalkanoates production. Further, the application of blends based on polyhydroxyalkanoates, and the challenges associated with the waste valorization based polyhydroxyalkanoates production strategy is elaborated in this review work.

Solidification of concentrated pea protein-pectin mixtures as potential binder.

BACKGROUND: Binders in plant-based meat analogues allow different components, such as extrudate and fat particles, to stick together. Typically, binders then are solidified to transform the mass into a non-sticky, solid product. As an option for a clean-label binder possessing such properties, the solidification behavior of pea protein-pectin mixtures (250 g kg-1 , r = 2:1, pH 6) was investigated upon heating, and upon addition of calcium, transglutaminase, and laccase, or by combinations thereof. RESULTS: Mixtures of (homogenized) pea protein and apple pectin had higher elastic moduli and consistency coefficients and lower frequency dependencies upon calcium addition. This indicated that calcium physically cross-linked pectin chains that formed the continuous phase in the biopolymer matrix. The highest degree of solidification was obtained with a mixture of pea protein and sugar beet pectin upon addition of laccase that covalently cross-linked both biopolymers involved. All solidified mixtures lost their stickiness. A mixture of soluble pea protein and apple pectin solidified only slightly through calcium and transglutaminase, probably due to differences in the microstructural arrangement of the biopolymers. CONCLUSION: The chemical makeup of the biopolymers and their spatial distribution determines solidification behavior in concentrated biopolymer mixtures. In general, pea protein-pectin mixtures can solidify and therefore have the potential to act as binders in meat analogues. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Sporopollenin - Invincible biopolymer for sustainable biomedical applications.

The objective of this review article is to present the utility of Sporopollenin, a natural biopolymer, for a wide range of applications. Sporopollenin is a ubiquitous natural polymer and chief ingredient of plant pollen grains, spores and it is chemically inert. Sporopollenin has a beautifully sculpted, decorated, and nano porous surface that is species unique. In both organic and aqueous solutions, it is stable. Purified sporopollenin keeps its spore or pollen particle shape, size, and surface properties while remaining an empty shell (sporopollenin microcapsules). Sporopollenin microcapsules and Sporopollenin Exine Shells (SEC) from pollen grains of plants (Angiosperms), spores of Bryophytes, Pteridophytes Gymnosperms and fungi have been developed as new biomaterials for drug/vaccine delivery, catalyst support, and heavy metal removal, among other sustainable applications. This review paper could pave the way for further research into sporopollenin production and the development of novel biomimetic polymers with desirable inert characteristics. The authors anticipate that this unique renewable polymer, which is abundant in nature and can be made from a variety of plants and fungal sources, will have biomedical applications contributing to sustainability in the future.

Comprehensive approach to the protection and controlled release of extremely oxygen sensitive probiotics using edible polysaccharide-based coatings.

The human intestinal system is a complex of various anaerobes including extremely oxygen-sensitive (EOS) bacteria, some of which have been credited with significant health benefits. Among these, Faecalibacterium prausnitzii, which is one of the most abundant anaerobic bacterial strains in the human intestinal tract, has been proved to be a promising probiotic for the treatment of inflammatory bowel diseases. However, because of its extremely sensitive nature, there are many difficulties when passing through the harsh environment of the gastrointestinal tract. Hence, in this study, a comprehensive physicochemical characterization was performed for the use of polysaccharides from several origins (hydroxypropyl methyl cellulose, methyl cellulose, hydroxypropyl cellulose, chitosan, low-methoxylated pectin, kappa-carrageenan, sodium alginate and pullulan) as encapsulating agents to protect and deliver this bacterium. First, the apparent viscosity and surface tension of the polymer solutions were tested. Then, the mechanical properties, water vapor and oxygen barrier properties of these biopolymers as self-standing films were investigated. Lastly, in vitro release profiles of small molecules and bacterial cells from these biopolymer matrices in contact with a simulated gastrointestinal tract were evaluated. The results showed that chitosan, low-methoxylated pectin, kappa-carrageenan, sodium alginate and pullulan films exhibited good oxygen barrier properties to protect EOS probiotics. Among all the biopolymers tested, sodium alginate exhibited the best oxygen barrier properties and release profile. The release kinetics can be modulated by several factors including biopolymer type, plasticizer concentration and active molecules or bacteria to be encapsulated. On that basis and integrating the other parameters analyzed, a multicriteria strategy for probiotic encapsulation was proposed.

Opportunities in the microbial valorization of sugar industrial organic waste to biodegradable smart food packaging materials.

Many petroleum-derived plastics, including food packaging materials are non-biodegradable and designed for single-use applications. Annually, around 175 Mt. of plastic enters the land and ocean ecosystems due to mismanagement and lack of techno economically feasible plastic waste recycling technologies. Renewable sourced, biodegradable polymer-based food packaging materials can reduce this environmental pollution. Sugar production from sugarcane or sugar beet generates organic waste streams that contain fermentable substrates, including sugars, acids, and aromatics. Microbial metabolism can be leveraged to funnel those molecules to platform chemicals or biopolymers to generate biodegradable food packaging materials that have active or sensing molecules embedded in biopolymer matrices. The smart package can real-time monitor food quality, assure health safety, and provide economic and environmental benefits. Active packaging materials display functional properties such as antimicrobial, antioxidant, and light or gas barrier. This article provides an overview of potential biodegradable smart/active polymer packages for food applications by valorizing sugar industry-generated organic waste. We highlight the potential microbial pathways and metabolic engineering strategies to biofunnel the waste carbon efficiently into the targeted platform chemicals such as lactic, succinate, muconate, and biopolymers, including polyhydroxyalkanoates, and bacterial cellulose. The obtained platform chemicals can be used to produce biodegradable polymers such as poly (butylene adipate-co-terephthalate) (PBAT) that could replace incumbent polyethylene and polypropylene food packaging materials. When nanomaterials are added, these polymers can be active/smart. The process can remarkably lower the greenhouse gas emission and energy used to produce food-packaging material via sugar industrial waste carbon relative to the petroleum-based production. The proposed green routes enable the valorization of sugar processing organic waste into biodegradable materials and enable the circular economy.

Sporopollenin based materials as a versatile choice for the detoxification of environmental pollutants - A review.

Before making the transfer to land, plants survive in water for millions of years to avoid the severe circumstances that prevail on lands, such as drought and UV radiation. All land plant spores are coated in sporopollenin, a substance that has developed to endow pollen and spore shells with exceptional, one-of-a-kind qualities. In a nutshell, sporopollenin-coated spores are a unique invention only seen in land plants. Sporopollenin, discovered in the outer exine layer of pollen walls, is a lipid and phenolic-based polymer with high carbon, hydrogen, and oxygen cross-linking. Products based on sporopollenin can remediate toxic pollutant contamination in the aquatic environment. This research and development are now underway. In this review, we show how sporopollenin-based adsorbents act in environmental challenges and their immense promise for this application via remarkable physical and chemical characteristics. A comparison is made of the benefits of various sporopollenin-modified structures. This strategy will further our understanding of how a biopolymer's structure can be accommodated to address emerging environmental challenges, revealing more about sporopollenin's dynamical nature.

Biopolymer Composites: Synthesis, Properties, and Applications.

Petroleum-based plastics can be found everywhere in our habitual life in diverse applications such as automobiles, aerospace, and medical science [...].

Enhancing bioaccessibility of resveratrol by loading in natural porous starch microparticles.

Resveratrol (RSV) is a lipophilic polyphenol susceptible to photo- and thermal degradation, and strategies are to be studied to enable its distribution in food matrices, prevent its degradation during storage, and increase its bioaccessibility during digestion. In this study, the porous matrix of natural starch, in the form of milled freeze-dried potato microparticles (FDPMs), was studied as an absorbent to load RSV. The binary solvent of ethanol and polyethylene glycol 400 (40:60 v/v) was used to dissolve 30% w/v RSV for diffusion into FDPMs. After ethanol was evaporated, the loading capacity was 112 mg RSV/g FDPMs and was maintained at 104 mg RSV/g FDPMs (92.9% retention) after 110-day ambient storage. The RSV stability under UV irradiation at 253 nm was improved by 32% due to shielding effect of FDPMs, and the ferric reducing power was 25% higher than the pristine RSV. The release of RSV in FDPMs was significantly higher than pristine RSV during simulated gastric and intestinal digestions (82.3% vs 51.4% bioaccessibility). The increased reducing power and bioaccessibility were supported by the amorphous state of RSV in FDPMs. The present study illustrates the potential of porous vegetable microparticles as natural matrices to load lipophilic bioactive compounds in functional foods.

Enhancing the functional properties of rice starch through biopolymer blending for industrial applications: A review.

Rice starch has been used in various agri-food products due to its hypoallergenic properties. However, rice starch has poor solubility, lower resistant starch content with reduced retrogradation and poor functional properties. Hence, its industrial applications are rather limited. The lack of comprehensive information and a holistic understanding of the interaction between rice starch and endo/exogenous constituents to improve physico-chemical properties is a prerequisite in designing industrial products with enhanced functional attributes. In this comprehensive review, we highlight the potentials of physically mixing of biopolymers in upgrading the functional characteristics of rice starch as a raw material for industrial applications. Specifically, this review tackles rice starch modifications by adding natural/synthetic polymers and plasticizers, leading to functional blends or composites in developing sustainable packaging materials, pharma- and nutraceutical products. Moreover, a brief discussion on rice starch chemical and genetic modifications to alter starch quality for the deployment of rice starch industrial application is also highlighted.

Complementary experimental/docking approach for determining chitosan and carboxymethylchitosan ability for the formation of active polymer-ß-galactosidase adducts.

The spontaneous aggregation of chitosan and carboxymethylchitosan polymers can be advantageous for the enzyme confinement on these colloidal systems during immobilization processes. The initial crucial step involves the polymer-enzyme adduct formation. The objective here is to determine the interactions that drive the adduct formation between these polymers and ß-galactosidase from Bacillus circulans. The chemical characterization of chitosan and its carboxymethyl-derivate allowed to explain their colloidal behavior and design the four-unit fragments ligands used for the docking study. The deacetylation degree (0.6 times lower), isoelectric point (5.2 instead 6.4) and substitution degree (DSO = 1.779 and DS2N = 0.441) of carboxymenthylchitosan are due to the hydroxide concentration (>25%) and 30 °C modification conditions. Favorable Van der Waals and H-bond interactions between chitosan-ß-galactosidase and contribution of electrostatic attraction mediated by calcium ions for carboxymethylchitosan-ß-galactosidase explained the zeta potential and dynamic light scattering results at pH 7.0. These interactions occur onto the external surface of this galactosidase, without affecting the catalytic activity. A cross-linked enzyme aggregates-type model was proposed for the formation of the adducts, based on the complementary experimental-docking results. They contribute understanding the behavior of polyelectrolyte chitosan-derived matrices for enzyme immobilization.

Development of multifunctional food packaging films based on waste Garlic peel extract and Chitosan.

A sustainable multifunctional food packaging composite film containing waste garlic peel extract (GPE) and Chitosan (CH) was prepared. This film exhibited antimicrobial potential towards Staphylococcus aureus and Klebsiella pneumoniae. GPE/CH films' morphological, physical, and functional properties were compared to those of CH film. Fourier transform infrared showed the interactions through hydrogen bonding between CH and GPE in the blends that improved the polymers' compatibility. Furthermore, X-ray diffraction analysis validated the compatibility between GPE and CH. GPE/CH films exhibited higher thickness and moisture content than the CH film. Remarkably, GPE/CH films showed lower water vapor barrier properties and higher ultra-violet protection and mechanical strength than CH film. Compact surfaces of the GPE infused CH films were unveiled through Scanning electron microscopy. GPE/CH film showed improved thermal stability after the addition of GPE. MTT method's cytotoxicity study manifested that the GPE/CH films are antioxidant and non-cytotoxic, implicating their biocompatibility and non-toxicity. The results suggest that GPE/CH films can find widespread commercial applications like food packaging materials, replacing the commonly used petrochemical plastics.

Progresses in chitin, chitosan, starch, cellulose, pectin, alginate, gelatin and gum based (nano)catalysts for the Heck coupling reactions: A review.

Heck cross-coupling reaction (HCR) is one of the few transition metal catalyzed CC bond-forming reactions, which has been considered as the most effective, direct, and atom economical synthetic method using various catalytic systems. Heck reaction is widely employed in numerous syntheses including preparation of pharmaceutical and biologically active compounds, agrochemicals, natural products, fine chemicals, etc. Commonly, Pd-based catalysts have been used in HCR. In recent decades, the application of biopolymers as natural and effective supports has received attention due to their being cost effective, abundance, and non-toxicity. In fact, recent studies demonstrated that biopolymer-based catalysts had high sorption capacities, chelating activities, versatility, and stability, which make them potentially applicable as green materials (supports) in HCR. These catalytic systems present high stability and recyclability after several cycles of reaction. This review aims at providing an overview of the current progresses made towards the application of various polysaccharide and gelatin-supported metal catalysts in HCR in recent years. Natural polymers such as starch, gum, pectin, chitin, chitosan, cellulose, alginate and gelatin have been used as natural supports for metal-based catalysts in HCR. Diverse aspects of the reactions, different methods of preparation and application of polysaccharide and gelatin-based catalysts and their reusability have been reviewed.

New Active Packaging Based on Biopolymeric Mixture Added with Bacteriocin as Active Compound.

The objective of this work was to develop a chitosan/agar-agar bioplastic film incorporated with bacteriocin that presents active potential when used as food packaging. The formulation of the film solution was determined from an experimental design, through the optimization using the desirability function. After establishing the concentrations of the biopolymers and the plasticizer, the purified bacteriocin extract of Lactobacillus sakei was added, which acts as an antibacterial agent. The films were characterized through physical, chemical, mechanical, barrier, and microbiological analyses. The mechanical properties and water vapor permeability were not altered by the addition of the extract. The swelling property decreased with the addition of the extract and the solubility increased, however, the film remained intact when in contact with the food, thus allowing an efficient barrier. Visible light protection was improved by increased opacity and antibacterial capacity was effective. When used as Minas Frescal cream cheese packaging, it contributed to the increase of microbiological stability, showing a reduction of 2.62 log UFC/g, contributing a gradual release of the active compound into the food during the storage time. The film had an active capacity that could be used as a barrier to the food, allowing it to be safely packaged.

Ultrasound-Assisted Microencapsulation of Soybean Oil and Vitamin D Using Bare Glycogen Nanoparticles.

Ultrasonically synthesized core-shell microcapsules can be made of synthetic polymers or natural biopolymers, such as proteins and polysaccharides, and have found applications in food, drug delivery and cosmetics. This study reports on the ultrasonic synthesis of microcapsules using unmodified (natural) and biodegradable glycogen nanoparticles derived from various sources, such as rabbit and bovine liver, oyster and sweet corn, for the encapsulation of soybean oil and vitamin D. Depending on their source, glycogen nanoparticles exhibited differences in size and 'bound' proteins. We optimized various synthetic parameters, such as ultrasonic power, time and concentration of glycogens and the oil phase to obtain stable core-shell microcapsules. Particularly, under ultrasound-induced emulsification conditions (sonication time 45 s and sonication power 160 W), native glycogens formed microcapsules with diameter between 0.3 µm and 8 µm. It was found that the size of glycogen as well as the protein component play an important role in stabilizing the Pickering emulsion and the microcapsules shell. This study highlights that native glycogen nanoparticles without any further tedious chemical modification steps can be successfully used for the encapsulation of nutrients.