Pectin Hydrogels: Gel-Forming Behaviors, Mechanisms, and Food Applications

Pectin-Cellulose Nanofiber Composites: Biodegradable Materials for Modified Atmosphere Packaging

Pectin blended with cellulose nanofiber (CNF) sourced from wood pulp has excellent potential for modified atmosphere packaging (MAP), as demonstrated with refrigerated or sliced fruits enclosed in parchment coated with pectin-CNF composites. Addition of sodium borate (NaB) augments the antioxidant capacity of the composite, most likely through the generation of unsaturated pectic acid units. Packaging materials coated with pectin-CNF-NaB composites demonstrate better humidity regulation in refrigerated spaces over a 3-week period relative to uncoated controls (50% less variation), with improved preservation of strawberries as well as a reduction in the oxidative browning of sliced apples. Pectin-CNF films are both biorenewable and biodegradable as confirmed by their extensive decomposition in soil over several weeks, establishing their potential as a sustainable MAP material. Lastly, self-standing films are mechanically robust at 80% RH with tensile strength and toughness as high as 150 MPa and 8.5 MJ/m2 respectively. These values are on par with other bioplastic composites and support the practical utility of pectin-CNF composites in functional packaging applications.

Effect of glycerol diglycidyl ether crosslinker on pectin-starch blended pharmaceutical films

Pharmaceutical films can show versatility and biocompatibility. Pectin and starch blends crosslinked with glycerol diglycidyl ether (GDE) can improve the physicochemical properties of films. This study aimed to develop films with pectin and starch crosslinked with GDE. They were prepared by solvent evaporation technique, using different amounts of polymers and GDE. The total solids concentration was optimized to 5.0 % (w/w) and dried at 35 °C. Films were evaluated for thickness, density and by ATR-FTIR, TGA, DSC, tensile tests, swelling capacity, water vapor permeability, SEM and in-vitro cytotoxicity (Artemia salina, VERO and L-929 cells). The thickness of the crosslinked films was between 0.142 mm and 0.150 mm. ATR-FTIR analysis showed probable crosslinking between the polysaccharides and GDE. Thermal and mechanical analyses showed thermal stability below Tg for those crosslinked with GDE and improved mechanical strength. Crosslinked films absorbed more water at neutral pH than in acidic medium, indicating pH-dependent behavior. At neutral pH, they exhibited a hydrated structure with homogeneous pore distribution, while at acidic pH, the distribution was more heterogeneous and in lower quantity. The films were not cytotoxic. These results highlight the potential of GDE cross-linked pectin-starch films as a viable and innovative alternative for future pharmaceutical applications.

Gel properties of sheep's hoof gelatin-dietary polysaccharide interpenetrating polymer network complex gels with application in low fat lamb patties

In order to explore new fat substitutes, we compared three dietary polysaccharides Pectin(PEC), Inulin (INU), and Konjac glucomannan (KGM) compounded with sheep hoof gelatin using different cross-linking methods [transglutaminase (Tg) enzyme; Tg enzyme & Ca2+] for the preparation of Semi-interpenetrating polymer network (Semi-IPN) and fully interpenetrating polymer network (IPN) gels. The optimal ratio was determined by comprehensively evaluating the addition of hydrogel to the lamb patties at different ratios. The results showed that PEC-IPN exhibited superior stability and textural properties compared to the Semi-IPN gels and control gels in each group. In addition, replacing 80 % of the fat in the lamb patties with PEC-IPN significantly improved the quality stability during storage, without affecting the sensory quality. Therefore, PEC-IPN instead of lamb patty fat offers a new approach for consumers.

Pectin-Based Active and Smart Film Packaging: A Comprehensive Review of Recent Advancements in Antimicrobial, Antioxidant, and Smart Colorimetric Systems for Enhanced Food Preservation

This review provides a comprehensive overview of recent advancements in biodegradable active and smart packaging utilizing pectin from various origins for food applications. It critically examines the challenges and limitations associated with these developments, initially focusing on the structural influences of pectin on the properties of packaging films. Methods such as spray drying, casting, and extrusion are detailed for manufacturing pectin films, highlighting their impact on film characteristics. In discussing active pectin films, the review emphasizes the effectiveness of incorporating essential oils, plant extracts, and nanoparticles to enhance mechanical strength, moisture barrier properties, and resistance to oxidation and microbial growth. Smart biodegradable packaging is a significant research area, particularly in monitoring food freshness. The integration of natural colorants such as anthocyanins, betacyanins, and curcumin into these systems is discussed for their ability to detect spoilage in meat and seafood products. The review details the specific mechanisms through which these colorants interact with food components and environmental factors to provide visible freshness indicators for consumers. It underscores the potential of these technologies to fulfill sustainability goals by providing eco-friendly substitutes for traditional plastic packaging.

A Novel Liposomal In-Situ Hydrogel Formulation of Hypericum perforatum L.: In Vitro Characterization and In Vivo Wound Healing Studies

Hypericum perforatum L. (H.P.) is a species with a well-documented history of use in wound healing practices across the globe. The objective of this study was twofold: firstly, to evaluate the in vivo efficacy of liposomal in situ gel formulations in wound healing, both clinically and histopathologically, and secondly, to determine the physicochemical characterization of liposomal in situ gel formulations. The in vitro studies will be assessed in terms of particle size, zeta potential, release kinetics, rheological behaviors, and antioxidant and antimicrobial properties. The in vivo studies will be evaluated in clinical animal experiments and pathology studies. The in-situ hydrogel formulations were prepared using the physical cross-linking method with Poloxamer 188, Poloxamer 407, Ultrez 21, and Ultrez 30. The liposome formulations phospholipid 90H and lipoid S100 were prepared using the thin film solvent evaporation method. The antioxidant activity of the samples was evaluated through in vitro studies employing the DPPH antioxidant activity, ABTS+ test, and FRAP test. The antimicrobial activity of the samples was evaluated through the determination of MIC and MBC values employing the 96-well plate method. In vivo, 36 male New Zealand rabbits aged 32-36 weeks were utilized, with six rabbits in each group. The groups were composed of six distinct groups, including conventional and in situ gel liposome formulations of HHPM, three different commercial preparations, and a control group (n = 6). The HHPM-LG8 formulation developed in this study was found to be applicable in terms of all its properties. The new liposomal in situ hydrogel formulation demonstrated notable wound healing activity, a result that was supported by the formulation itself.

Potential of Annatto Seeds (Bixa orellana L.) Extract Together with Pectin-Edible Coatings: Application on Mulberry Fruits (Morus nigra L.)

Morus nigra L., or mulberry, is a susceptible fleshy fruit due to its high respiratory rate and low storage stability, which shortens its shelf life and makes it difficult to commercialize in natura. Edible coatings, thin membranes produced directly on the desired surface, could improve food preservation, among other properties. Annatto (Bixa orellana L.) seeds are natural pigments with high antioxidant activity. This work aimed to develop a pectin-based edible coating with annatto extract to increase the shelf life of fruits, using mulberries as a study model. The mulberries were randomly separated into five groups: without coating, coated with different extract concentrations (0%, 5%, and 10%), and a layer-by-layer treatment consisting of a pectin layer under a 10% extract layer. The samples were evaluated for the following parameters: titratable acidity, maturity index, mass loss, pH, soluble solids, moisture contents, and bioactive compounds. The coated group with 10% annatto extract had the best result for the maturity index (25.52), while the group with 5% showed better mass loss and moisture (37.28% and 83.66%, respectively). Herein, it was demonstrated that pectin-based edible coatings with annatto extract delay the maturation and senescence of mulberries, preserving the bioactive compounds and increasing shelf life.

Beyond Imitation: How Food Colloids Are Shaping the Next Generation of Biomimetic Foods

In the new global landscape of population, environmental, and energy sustainability, the manufacture of future food products that meet human nutritional and health needs is a major challenge. Biomimetic food, as a new type of food, has made significant progress in the use of plant proteins and other ingredients to mimic animal food, and it has also achieved important results in sensory and nutritional properties. In the study of biomimetic foods, food colloids play an irreplaceable role as the key framework for building food structures. In this paper, we first review the recent research progress on food colloids in the fields of biomimetic plant-based food, biomimetic animal-based food and 3D printed biomimetic food. Then, the mechanism of action, application effects, and quality improvement strategies of food colloids are deeply analyzed. Finally, the future research directions and application prospects are envisioned. This paper aims to give theoretical support and practical guidance for the development of biomimetic food through the above elaboration, to deal with the current problems in food development by means of the unique properties of food colloids, and to open up new ideas for the application of food colloids in future food innovation, and then to promote the further development of the field of biomimetic food.

Advancing Gel Systems with Natural Extracts: Antioxidant, Antimicrobial Applications, and Sustainable Innovations

The integration of natural extracts into gel systems has emerged as a transformative approach to enhance functional properties, including antioxidant, antimicrobial, and therapeutic effects. This review underscores the remarkable potential of natural extract-enriched gels, which effectively combine sustainability with improved functionality. These bioactive compounds, sourced from plants and animals, encompass polyphenols, flavonoids, essential oils, chitosan, proteins, and polysaccharides. They provide an eco-friendly alternative to synthetic additives and find applications across various sectors, including pharmaceuticals, cosmetics, and food packaging. Despite their promise, challenges remain, such as the variability in natural extract composition, the stability of bioactive compounds, and scalability for industrial use. To address these issues, innovative strategies like nanoencapsulation, responsive hydrogels, and AI-driven optimization have demonstrated significant progress. Additionally, emerging technologies, such as 3D printing and adherence to circular economy principles, further enhance the versatility, efficiency, and sustainability of these systems. By integrating these advanced tools and methodologies, gel systems enriched with natural extracts are well-positioned to meet contemporary consumer and industrial demands for multifunctional and eco-friendly products. These innovations not only improve performance but also align with global sustainability goals, setting the stage for widespread adoption and continued development in various fields.

Recent advances of bioaerogels in medicine: Preparation, property and application

Bioaerogels represent a type of three-dimensional porous materials fabricated from natural biopolymers, and show a significant potential for medical application due to their characteristics of extremely low density, high specific surface area, excellent biocompatibility and biodegradability. The preparation method and parameters of bioaerogels are focused on, and their influence on the structure and properties of bioaerogels are discussed in detail. Then, to match the properties of bioaerogels with the medical applications, this work emphasizes the main properties (including biocompatibility, degradability, and mechanical properties), structural parameters (such as suitable porosity, pore size and high specific surface area), and further summarizes the influence of single-component and composite bioaerogels on their properties. Moreover, according to the different applications (wound healing, drug delivery, and tissue engineering and other fields), the function method, mechanism and practical effect of bioaerogels are comprehensively analyzed. Finally, the challenges, future research directions, and solutions for the practical application of bioaerogels in medicine are discussed.

Development and characterization of bael fruit gum-pectin hydrogel for enhanced antimicrobial activity

Natural polymers are crucial for developing sustainable biomedical solutions, as their bioactivity, biocompatibility, and biodegradability make them superior alternatives to synthetic materials. The objective of the study is to develop and characterize a chemically modified bael fruit gum (BFG) and pectin hydrogel to enhance antimicrobial activity. Due to BFG's anionic nature, it was chemically modified to introduce cationic groups, facilitating cross-linking with pectin. Physicochemical characterization of BFG and pectin was conducted using FTIR and DSC, which confirmed functional groups and thermal stability, respectively. Hydrogel optimization was achieved through Central Composite Design (CCD). Rheological evaluations indicated shear-thinning behavior with a viscosity reduction under high shear stress, reflecting thixotropic properties. The hydrogel exhibited satisfactory erosion and swelling within 24 h, suggesting controlled release. Zeta potential measurements confirmed the hydrogel's stability, attributed to its negative surface charge. SEM revealed a porous structure, aiding in drug encapsulation and release. Antimicrobial testing showed synergistic antimicrobial effects with inhibition zones of 1.4 cm and 1.5 cm against Staphylococcus aureus and Escherichia coli, respectively. Stability studies demonstrated robustness over time. Overall, this study highlights the potential of natural polymer-based hydrogels as sustainable alternatives to synthetic polymers in pharmaceutical and biomedical fields, offering safer, environmentally friendly solutions.

Impact of chia seed protein hydrolysate and apple pomace pectin on the properties of egg-free mayonnaise

This study investigates the properties of egg-free mayonnaise prepared using chia seed protein hydrolysate (CSPH) and pectin extracted from apple pomace (PA) as alternatives to egg, comparing it to traditional egg-based mayonnaise. Chia seed protein was hydrolyzed using Protamex and Bromelain enzymes, while apple pectin was extracted through acid hydrolysis at 90 °C. Four mayonnaise treatments were prepared: T1 (control: 6 % egg), T2 (4 % egg + 1 % CSPH + 1 % PA), T3 (2 % egg + 2 % CSPH + 2 % PA), and T4 (0 % egg + 3 % CSPH + 3 % PA). The physicochemical, textural, and sensory properties of the mayonnaise samples were evaluated. The CSPH produced with the Protamex enzyme exhibited a higher protein content and greater degree of hydrolysis (P < 0.05), establishing it as a suitable egg substitute. Replacing egg with CSPH and PA resulted in increased acidity, physical and thermal stability, viscosity, firmness, and adhesiveness of the mayonnaise, while reducing lightness, pH, and overall sensory scores. Treatments T3 and T4 demonstrated superior overall properties compared to other treatments; however, T3 received the highest sensory scores. These findings suggest that pectin and hydrolyzed protein can effectively replace egg in mayonnaise production, offering a viable alternative for individuals with egg allergies and those seeking healthier options.

A comprehensive review on the functionality and biological relevance of pectin and the use in the food industry

Pectin is a natural biopolymer, which can be extracted from food by-products, adding value to raw material, with a structure more complex than that of other polysaccharides. The gelling properties of these molecules, together with the bioactivity that these can exert, make them suitable to be used as ingredients and bioactive agents. In this review, the characterization of pectin (structure, sources, techno-functional, and biological properties), the extraction methods, and their use in the food industry (food packaging, as carriers, and as ingredients) are described. Different by-products can be used as substrates to extract pectin, enhancing a sustainable food system as described by the circular economy principles. Pectin is characterized for their techno-functional and biological properties, such as gelling and thickening properties or modulation of microbiota both in animals and humans. Such properties make these molecules suitable for a wide range of applications within the food chain, serving as packaging or carriers in foodstuff, or for direct use as functional ingredients as fiber. Overall, pectin has been shown to exert as promising components to be introduced in the food system, although further research on scaling-up the production process and feasibility has to be done.

Acidic dimethyl sulfoxide: A solvent system for the fast dissolution of pectin derivatives suitable for subsequent modification

This study investigates the use of dimethyl sulfoxide (DMSO) as a solvent for the dissolution and subsequent chemical modification of various pectin derivatives. DMSO was found to effectively dissolve low-methoxy pectin, high-methoxy pectin, polygalacturonic acid hydrazide, pectin amide, and polygalacturonic hydroxamic acid when the negative charges on the polysaccharide backbone were neutralized with organic acids. The dissolution process was further enhanced by increasing the temperature, although higher temperatures also promoted chain cleavage. The dissolved pectin derivatives were successfully modified through transesterification and Schiff base formation, demonstrating the potential of acidic DMSO as a non-toxic and cost-effective solvent system for homogeneous pectin chemistry. The study opens new possibilities for the functionalization of pectin in various industrial and biomedical applications.

Advances in bio-polymer coatings for probiotic microencapsulation: chitosan and beyond for enhanced stability and controlled release

This review paper analyzes recent advancements in bio-polymer coatings for probiotic microencapsulation, with a particular emphasis on chitosan and its synergistic combinations with other materials. Probiotic microencapsulation is essential for protecting probiotics from environmental stresses, enhancing their stability, and ensuring effective delivery to the gut. The review begins with an overview of probiotic microencapsulation, highlighting its significance in safeguarding probiotics through processing, storage, and gastrointestinal transit. Advances in chitosan-based encapsulation are explored, including the integration of chitosan with other bio-polymers such as alginate, gelatin, and pectin, as well as the application of nanotechnology and innovative encapsulation techniques like spray drying and layer-by-layer assembly. Detailed mechanistic insights are integrated, illustrating how chitosan influences gut microbiota by promoting beneficial bacteria and suppressing pathogens, thus enhancing its role as a prebiotic or synbiotic. Furthermore, the review delves into chitosan's immunomodulatory effects, particularly in the context of inflammatory bowel disease (IBD) and autoimmune diseases, describing the immune signaling pathways influenced by chitosan and linking gut microbiota changes to improvements in systemic immunity. Recent clinical trials and human studies assessing the efficacy of chitosan-coated probiotics are presented, alongside a discussion of practical applications and a comparison of in vitro and in vivo findings to highlight real-world relevance. The sustainability of chitosan sources and their environmental impact are addressed, along with the novel concept of chitosan's role in the gut-brain axis. Finally, the review emphasizes future research needs, including the development of personalized probiotic therapies and the exploration of novel bio-polymers and encapsulation techniques.

Applications of Natural Polymers in the Grapevine Industry: Plant Protection and Value-Added Utilization of Waste

The grapevine industry is confronted with challenges such as plant stress from environmental factors and microbial infections, alongside the need for sustainable waste management practices. Natural polymers offer promising solutions to these issues due to their biocompatibility, biodegradability, and functional versatility. This review explores the dual role of natural polymers in enhancing the grapevine industry: as protective agents against various stressors and as carriers for the delivery of valuable compounds recovered from grapevine wastes. We examine the use of natural polymers such as chitosan, alginate, and cellulose in formulating bio-based protective coatings and treatments that bolster plant resistance to abiotic stress, pathogens, and pests. Additionally, the review delves into the innovative utilization of grapevine residues, including skins, seeds, and stems, as sources of polyphenols and other bioactive compounds. These compounds can be efficiently encapsulated in natural polymer matrices for applications in agriculture, food, and pharmaceuticals. Key topics include the mechanisms of action, benefits, and limitations of natural polymer-based interventions, as well as case studies demonstrating their practical implementation in vineyards. The review also addresses future research directions, emphasizing the need for integrated approaches that enhance sustainability and economic viability in the grapevine industry.

Polysaccharide-Based Drug Carriers-A Patent Analysis

Polysaccharide-based carriers as biomaterials for drug delivery have been inspiring scientists for years due to their exceptional characteristics, such as nontoxicity, biocompatibility, and degradability, as they are able to protect pharmaceutically active molecules and provide their controlled/modified release. This review focuses on selected drug delivery systems based on natural polymers, namely fucoidan, pullulan, dextran, and pectin, with the aim of highlighting published patent documents. The information contained in patents is very important because it is usually not published in any other document and is much less discussed as the state of the art in the scientific literature. The Espacenet-European Patent Office database and the International Patent Classification were used for the research to highlight the specific search procedure. The presented analysis of the innovative state of the art includes an overview from the first patent applications to the latest granted patents in this field.

Food Gels Based on Polysaccharide and Protein: Preparation, Formation Mechanisms, and Delivery of Bioactive Substances

Hydrogels have a unique three-dimensional network that can create a good environment for the loading of functional compounds; hence, they have considerable potential in the delivery of bioactive substances. Natural macromolecular substances (proteins, polysaccharides) have the features of low toxicity, degradability, and biosafety; thus, they can be employed in the manufacture of hydrogels in the food sector. With its customizable viscoelastic and porous structure, hydrogels are believed to be good bioactive material delivery vehicles, which can effectively load polyphenols, vitamins, probiotics, and other active substances to prevent their influence from the external environment, thereby improving its stability. In this research, the common raw materials, preparation methods, and applications in the delivery of bioactive elements of food gels were examined; this study aimed at presenting new ideas for the development and utilization of protein-based food gels.

Fabrication of food polysaccharide, protein, and polysaccharide-protein composite gels via calcium ion inducement: Gelation mechanisms, conditional factors, and applications

Food gel is a kind of macromolecular biopolymer with viscoelasticity, which has good water retention and gelling ability, especially gels formed by protein and/or polysaccharide. The addition of calcium ions triggers gelation by interacting with the gel matrix, enhancing gels' textural and rheological properties like hardness, viscosity and elasticity. Thus calcium ions enrich the range of applications of food gels. This review focuses on forming a calcium-induced gel and improving the texture properties. It summarizes the mechanisms of gelation induced by calcium ions in polysaccharide, protein, and polysaccharide-protein systems and their gel properties. The effects of influencing factors in calcium ion concentration, types and mixing ratios of matrices, acid, and alkaline environments, as well as treatment methods on calcium-induced gel characteristics, are presented. Additionally, the current applications of calcium-induced gels in food industries and challenges are presented.

3D printed personalized therapies for pediatric patients affected by adrenal insufficiency

BACKGROUND

Adrenal insufficiency is usually diagnosed in children who will need lifelong hydrocortisone therapy. However, medicines for pediatrics, in terms of dosage and acceptability, are currently unavailable.

RESEARCH DESIGN AND METHODS

Semi-solid extrusion (SSE) 3D printing (3DP) was utilized for manufacturing of personalized and chewable hydrocortisone formulations (printlets) for an upcoming clinical study in children at Vall d'Hebron University Hospital in Barcelona, Spain. The 3DP process was validated using a specific software for dynamic dose modulation.

RESULTS

The printlets contained doses ranging from 1 to 6 mg hydrocortisone in three different flavor and color combinations to aid adherence among the pediatric patients. The pharma-ink (mixture of drugs and excipients) was assessed for its rheological behavior to ensure reproducibility of printlets through repeated printing cycles. The printlets showed immediate hydrocortisone release and were stable for 1 month of storage, adequate for prescribing instructions during the clinical trial.

CONCLUSIONS

The results confirm the suitability and safety of the developed printlets for use in the clinical trial. The required technical information from The Spanish Medicines Agency for this clinical trial application was compiled to serve as guidelines for healthcare professionals seeking to apply for and conduct clinical trials on 3DP oral dosage forms.

Structure formation mechanism of pectin-soy protein isolate gels: Unraveling the role of peach pectin fractions

This study investigated the macro & micro properties of the composite gels formed by soy protein isolate (SPI) and peach pectin fractions: water-soluble pectin (WSP), chelator-soluble pectin (CSP), and sodium carbonate soluble pectin (NSP). Specially, the interaction between pectin fractions and SPI was studied to explain the formation mechanism of the composite gels. WSP, as a high methoxyl pectin, exhibited rich branching (sugar ratio B = 3.10). CSP, as a low methoxyl pectin, depicted a high linearity. NSP, with low linearity (sugar ratio A = 6.14), contained numerous side chains. Due to the strong interaction between pectin fractions and SPI, the new composites with excellent dense network microstructures were formed, accompanied by increased apparent viscosity, higher G' and G'', and reduced particle size. XRD and FT-IR analysis highlighted the modifications in gel structures. SEM-dispersive X-ray spectroscopy observed elemental distribution and framework composition in pectin-SPI gels. Hydrophobic interaction was the most important chemical force in pectin-SPI binding. Molecular docking results indicated that galacturonic acid in pectin bound more strongly to 7S than to 11S, with tighter hydrogen bonds. Notably, WSP-SPI showed the lowest turbidity, indicating enhanced solubility and particle dispersion, which helped prevent aggregation. CSP-SPI demonstrated the highest G' and G'', ascribing to the high linearity and abundant carboxyl groups in CSP. NSP-SPI showed the highest apparent viscosity and irregular structure. Overall, the texture properties of pectin-SPI gels were driven by pectin's structure properties, which would provide new and valuable information for texture control in gel formulation.

In the process of polysaccharide gel formation: A review of the role of competitive relationship between water and alcohol molecules

Polysaccharides have emerged as versatile materials capable of forming gels through diverse induction methods, with alcohol-induced polysaccharide gels demonstrating significant potential across food, medicinal, and other domains. The existing research mainly focused on the phenomena and mechanisms of alcohol-induced gel formation in specific polysaccharides. Therefore, this review provides a comprehensive overview of the intricate mechanisms underpinning alcohol-triggered gelation of different polysaccharides and surveys their prominent application potentials through rheological, mechanical, and other characterizations. The mechanism underlying the enhancement of polysaccharide network structures by alcohol is elucidated, where alcohol displaces water to establish hydrogen bonding and hydrophobic interactions with polysaccharide chains. Specifically, alcohols change the arrangement of water molecules, and the partial hydration shell surrounding polysaccharide molecules is disrupted, exposing polysaccharides' hydrophobic groups and enhancing hydrophobic interactions. Moreover, the pivotal influences of alcohol concentration and addition method on polysaccharide gelation kinetics are scrutinized, revealing nuanced dependencies such as the different gel-promoting capabilities of polyols versus monohydric alcohols and the critical threshold concentrations dictating gel formation. Notably, immersion of polysaccharide gels in alcohol augments gel strength, while direct alcohol addition to polysaccharide solutions precipitates gel formation. Future investigations are urged to unravel the intricate nexus between the mechanisms underpinning alcohol-induced polysaccharide gelation and their practical utility, thereby paving the path for tailored manipulation of environmental conditions to engineer bespoke alcohol-induced polysaccharide gels.

One-pot biocatalysis of potato rhamnogalacturonan and the role of its deacetylation in efficient inhibition of colon cancer cells and hydrogel mediated colon-targeted drug delivery

Deacetylation of potato rhamnogalacturonan (PRG) by rhamnogalacturonan acetyl esterase (CtPae12B) was explored for enhanced hydrolysis of PRG by rhamnogalacturonan lyase (CtRGLf) and the effects of deacetylated PRG were studied in enhancing inhibition of colon-cancer cells and formation of colon-targeting drug delivery material. Pre-treatment of PRG with CtPae12B resulted in increased relative activity of CtRGLf. CtPae12B removed acetyl groups from both O-2 and O-3 positions of D-galactopyranosyluronic acid residues of PRG, resulting in 98 % deacetylation. PRG displayed 21.9 % degree of acetylation and 7.7 % degree of methylation. TLC and ESI-MS analysis of CtRGLf hydrolysed PRG showed unsaturated RG di-saccharide as the smallest product, with m/z 322. Deacetylated PRG-oligosaccharides displayed higher, 50 % inhibition of colon-cancer HCT-116 cells (with shrunken and globular morphology) than 35 % inhibition by acetylated PRG-oligosaccharides. FESEM and BET analysis of CtPae12B-treated PRG showed porous structure and significantly higher total surface area and pore volume than non-enzyme treated PRG. Higher drug entrapment efficiency and lower drug release rate of CtPae12B-treated PRG hydrogel (0.0033 min-1 at pH 1.2 and 0.009 min-1 at pH 7.4), than non-enzyme treated PRG hydrogel, (0.0057 min-1 at pH 1.2 and 0.02 min-1 at pH 7.4), showed it to be a potential biomaterial for sustainable colon-targeted drug delivery.

Valorisation of Blackcurrant Pomace by Extraction of Pectin-Rich Fractions: Structural Characterization and Evaluation as Multifunctional Cosmetic Ingredient

Blackcurrant pomace is a widely available waste stream derived from the industrial production of juice rich in pectin and unextracted polyphenols. Since pectin, an emerging class of gastrointestinal prebiotics, is also a common cosmetic ingredient, the aim of this work was to evaluate blackcurrant pomace as a source of pectin-rich fractions suitable for application in prebiotic cosmetics. Hereby, this raw material was valorised by sequential extraction of acid-soluble (by citric acid, CAP) and Ca-bound (by ammonium oxalate, AOPP) pectic polysaccharides. Both fractions had favourable physicochemical features and a similar degree of methyl-esterification between low- and high-methoxyl pectin (approx. 50%), but CAP had significantly higher galacturonic acid content (72.3%), branching, and purity. Regardless of that, both had very high oil (18.96 mL/g for CAP and 19.32 mL/g for AOPP) and water (9.97 mL/g for CAP and 7.32 mL/g for AOPP)-holding capacities and excellent emulsifying properties, making them promising cosmetic ingredients. The polyphenol content was 10 times higher in CAP, while corresponding antioxidant activity was 3-fold higher. Finally, the influence of varying CAP and AOPP concentrations on common skin pathogen, Staphylococcus aureus, and beneficial skin bacteria, Staphylococcus epidermidis, was examined. The results show significant prebiotic potential of two pectic fractions since they were capable of selectively stimulating S. epidermidis, while S. aureus growth was inhibited, whereas CAP demonstrated a particularly high capacity of up to 2.2, even with methicillin-resistant S. aureus.

Type A gelatin-amidated low methoxyl pectin complex coacervates for probiotics protection: Formation, characterization, and viability

This work developed and characterized the physicochemical properties of a type A gelatin and amidated low-methoxyl pectin complex coacervate (GA-LMAP-CC) hydrogel and evaluated its suitability for preserving the viability of probiotics under in vitro gastrointestinal conditions. The formation of GA-LMAP-CC was achieved via height electrostatic attraction at pH 3 and a mixing ratio of 1, exhibiting thermoreversible gel behavior. The hydrogel had a porosity of 44% and a water absorption capacity of up to 12 times. Water absorption profiles were obtained at different pH values (2, 5, and 7). The influence of GA-LMAP-CC depended on the medium, which controlled the hydration and water absorption rate. GA-LMAP-CC promoted the viability of B. longum BB536 and L. acidophilus strains under simulated gastrointestinal conditions, thereby enhancing their potential for intestinal colonization. The hydrogel has suitable properties for potential application in food and pharmaceutical areas to encapsulate and preserve probiotics.

Innovative Applications of Pectin in Lipid Management: Mechanisms, Modifications, Synergies, Nanocarrier Systems, and Safety Considerations

Pectin, a natural polysaccharide predominantly sourced from the cell walls of terrestrial plants, is widely regarded for its gelling, thickening, and stabilizing properties, which have extensive applications in the food, pharmaceutical, and biotechnological industries. This review discusses the mechanistic pathways by which pectin mediates its lipid-lowering properties, such as pectin's antioxidant activity, the modulation of gut microbiota, its anti-inflammatory properties, its capacity to bind bile acids and cholesterol, and its impact on the expression of genes associated with lipid metabolism. To enhance its hypolipidemic properties, chemical, physical, and enzymatic modification techniques are explored. Additionally, the synergistic effects of pectin in combination with other bioactive compounds such as phytosterols and polyphenols, as well as its potential in nanocarrier-mediated delivery systems for lipid-lowering agents, are highlighted. The review also conducts a critical analysis of the safety and regulatory considerations associated with pectin use, emphasizing the necessity for comprehensive toxicological evaluations and adherence to regulatory standards. This paper underscores the growing potential of pectin not only as a dietary fiber but also as a multifaceted agent for ameliorating hyperlipidemia, catalyzing a shift toward more targeted and efficacious lipid-lowering strategies.

Bacterial interactions on nutrient-rich surfaces in the gut lumen

The intestinal lumen is a turbulent, semi-fluid landscape where microbial cells and nutrient-rich particles are distributed with high heterogeneity. Major questions regarding the basic physical structure of this dynamic microbial ecosystem remain unanswered. Most gut microbes are non-motile, and it is unclear how they achieve optimum localization relative to concentrated aggregations of dietary glycans that serve as their primary source of energy. In addition, a random spatial arrangement of cells in this environment is predicted to limit sustained interactions that drive co-evolution of microbial genomes. The ecological consequences of random versus organized microbial localization have the potential to control both the metabolic outputs of the microbiota and the propensity for enteric pathogens to participate in proximity-dependent microbial interactions. Here, we review evidence suggesting that several bacterial species adopt organized spatial arrangements in the gut via adhesion. We highlight examples where localization could contribute to antagonism or metabolic interdependency in nutrient degradation, and we discuss imaging- and sequencing-based technologies that have been used to assess the spatial positions of cells within complex microbial communities.

Florfenicol core-shell composite nanogels as oral administration for efficient treatment of bacterial enteritis

To reduce the bitterness of florfenicol, avoid its degradation by gastric acid, and enhance its antibacterial activity against Escherichia coli by targeting and slowly releasing drugs at the site of intestinal infection, with pectin as an anion carrier and chitosan oligosaccharides (COS) as a cationic carrier, florfenicol-loaded COS@pectin core nanogels were self-assembled by electrostatic interaction and then encapsulated in sodium carboxymethylcellulose (CMCNa) shell nanogels through the complexation of CMCNa and Ca2+ to prepare florfenicol core-shell composite nanogels in this study. The florfenicol core-shell composite nanogels were investigated for their formula choice, physicochemical characterization, pH-responsive performances, antibacterial activity, therapeutic efficacy, and in vitro and in vivo biosafety studies. The results indicated that the optimized formula was 0.6 g florfenicol, 0.79 g CMCNa, 0.30 g CaCl2, 0.05 g COS, and 0.10 g pectin, respectively. In addition, the mean particle diameter, polydispersity index, zeta potential, loading capacity, and encapsulation efficiency were 124.0 ± 7.2 nm, -22.9 ± 2.5 mV, 0.42 ± 0.03, 43.4 % ± 3.1 %, and 80.5 % ± 3.4 %, respectively. The appearance, lyophilized mass, resolvability, scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (PXRD), and fourier transform infrared (FTIR) showed that the florfenicol core-shell composite nanogels were successfully prepared. Florfenicol core-shell composite nanogels had satisfactory stability, rheology, and pH-responsiveness, which were conducive to avoid degradation by gastric acid and achieve targeted and slow release at intestinal infection sites. More importantly, florfenicol core-shell composite nanogels had excellent antibacterial activity against Escherichia coli, a satisfactory therapeutic effect, and good palatability. In vitro and in vivo biosafety studies suggested the great promise of florfenicol core-shell composite nanogels. Therefore, the prepared florfenicol core-shell composite nanogels may be helpful for the treatment of bacterial enteritis as a biocompatible oral administration.

Oleogel Systems for Chocolate Production: A Systematic Review

In response to the growing demand for healthier food options, this review explores advances in oleogel systems as an innovative solution to reduce saturated fats in chocolates. Although appreciated for its flavor and texture, chocolate is high in calories, mainly due to cocoa butter (CB), which is rich in saturated fats. Oleogels, three-dimensional structures formed by structuring agents in edible oils, stand out in terms of mimicking saturated fats' physical and sensory properties without compromising the quality of chocolate. This study reviews how oleogels could improve chocolate's stability and sensory quality, exploring the potential of pectin-rich agro-industrial by-products as sustainable alternatives. It also explores the need for physicochemical evaluations of both oleogel and oleogel-based chocolate.

Hydrogels Based on Proteins Cross-Linked with Carbonyl Derivatives of Polysaccharides, with Biomedical Applications

Adding carbonyl groups into the hydrogel matrix improves the stability and biocompatibility of the hydrogels, making them suitable for different biomedical applications. In this review article, we will discuss the use of hydrogels based on polysaccharides modified by oxidation, with particular attention paid to the introduction of carbonyl groups. These hydrogels have been developed for several applications in tissue engineering, drug delivery, and wound healing. The review article discusses the mechanism by which oxidized polysaccharides can introduce carbonyl groups, leading to the development of hydrogels through cross-linking with proteins. These hydrogels have tunable mechanical properties and improved biocompatibility. Hydrogels have dynamic properties that make them promising biomaterials for various biomedical applications. This paper comprehensively analyzes hydrogels based on cross-linked proteins with carbonyl groups derived from oxidized polysaccharides, including microparticles, nanoparticles, and films. The applications of these hydrogels in tissue engineering, drug delivery, and wound healing are also discussed.

Extraction and Structural Analysis of Sweet Potato Pectin and Characterization of Its Gel

Pectin is widely used in the food and pharmaceutical industries. However, data on sweet potato pectin extraction and structural property analyses are lacking. Here, for the high-value utilization of agricultural processing waste, sweet potato residue, a byproduct of sweet potato starch processing, was used as raw material. Ammonium oxalate, trisodium citrate, disodium hydrogen phosphate, hydrochloric acid and citric acid were used as extractants for the pectin constituents, among which ammonium oxalate had a high extraction rate of sweet potato pectin, low ash content and high molecular weight. Structural and gelation analyses were conducted on ammonium oxalate-extracted purified sweet potato pectin (AMOP). Analyses showed that AMOP is a rhamnogalacturonan-I-type pectin, with a molecular weight of 192.5 kg/mol. Chemical titration and infrared spectroscopy analysis confirmed that AMOP is a low-ester pectin, and scanning electron and atomic force microscopy demonstrated its linear molecular structure. Gelation studies have revealed that Ca2+ is the key factor for gel formation, and that sucrose significantly enhanced gel hardness. The highest AMOP gel hardness was observed at pH 4, with a Ca2+ concentration of 30 mg/g, pectin concentration of 2%, and sucrose concentration of 40%, reaching 128.87 g. These results provide a foundation for sweet potato pectin production and applications.

Trends in polysaccharide-based hydrogels and their role in enhancing the bioavailability and bioactivity of phytocompounds

Over the years, polysaccharides such as chitosan, alginate, hyaluronic acid, k-carrageenan, xanthan gum, carboxymethyl cellulose, pectin, and starch, alone or in combination with proteins and/or synthetic polymers, have been used to engineer an extensive portfolio of hydrogels with remarkable features. The application of polysaccharide-based hydrogels has the potential to alleviate challenges related to bioavailability, solubility, stability, and targeted delivery of phytocompounds, contributing to the development of innovative and efficient drug delivery systems and functional food formulations. This review highlights the current knowledge acquired on the preparation, features and applications of polysaccharide/phytocompounds hydrogel-based hybrid systems in wound management, drug delivery, functional foods, and food industry. The structural, functional, and biological requirements of polysaccharides and phytocompounds on the overall performance of such hybrid systems, and their impact on the application domains are also discussed.

Current trend on preparation, characterization and biomedical applications of natural polysaccharide-based nanomaterial reinforcement hydrogels: A review

The tunable properties of hydrogels have led to their widespread use in various biomedical applications such as wound treatment, drug delivery, contact lenses, tissue engineering and 3D bioprinting. Among these applications, natural polysaccharide-based hydrogels, which are fabricated from materials like agarose, alginate, chitosan, hyaluronic acid, cellulose, pectin and chondroitin sulfate, stand out as preferred choices due to their biocompatibility and advantageous fabrication characteristics. Despite the inherent biocompatibility, polysaccharide-based hydrogels on their own tend to be weak in physiochemical and mechanical properties. Therefore, further reinforcement in the hydrogel is necessary to enhance its suitability for specific applications, ensuring optimal performance in diverse settings. Integrating nanomaterials into hydrogels has proven effective in improving the overall network and performance of the hydrogel. This approach also addresses the limitations associated with pure hydrogels. Next, an overview of recent trends in the fabrication and applications of hydrogels was presented. The characterization of hydrogels was further discussed, focusing specifically on the reinforcement achieved with various hydrogel materials used so far. Finally, a few challenges associated with hydrogels by using polysaccharide-based nanomaterial were also presented.

Application of Recurrence Plot Analysis to Examine Dynamics of Biological Molecules on the Example of Aggregation of Seed Mucilage Components

The goal of the research is to describe the aggregation process inside the mucilage produced by plant seeds using molecular dynamics (MD) combined with time series algorithmic analysis based on the recurrence plots. The studied biological molecules model is seed mucilage composed of three main polysaccharides, i.e. pectins, hemicellulose, and cellulose. The modeling of biological molecules is based on the assumption that a classical-quantum passage underlies the aggregation process in the mucilage, resulting from non-covalent interactions, as they affect the macroscopic properties of the system. The applied recurrence plot approach is an important tool for time series analysis and data mining dedicated to analyzing time series data originating from complex, chaotic systems. In the current research, we demonstrated that advanced algorithmic analysis of seed mucilage data can reveal some features of the dynamics of the system, namely temperature-dependent regions with different dynamics of increments of a number of hydrogen bonds and regions of stable oscillation of increments of a number of hydrophobic-polar interactions. Henceforth, we pave the path for automatic data-mining methods for the analysis of biological molecules with the intermediate step of the application of recurrence plot analysis, as the generalization of recurrence plot applications to other (biological molecules) datasets is straightforward.

Fabrication and characterization of a novel magnetic nanostructure based on pectin-cellulose hydrogel for in vitro hyperthermia during cancer therapy

Herein, a new magnetic nanobiocomposite based on a synthesized cross-linked pectin-cellulose hydrogel (cross-linked Pec-Cel hydrogel) substrate was designed and synthesized. The formation of the cross-linked Pec-Cel hydrogel with a calcium chloride agent and its magnetization process caused a new and efficient magnetic nanobiocomposite. Several spectral and analytical techniques, including FTIR, SEM, VSM, TGA, XRD, and EDX analyses, were performed to confirm and characterize the structural features of the magnetic cross-linked pectin-cellulose hydrogel nanobiocomposite (magnetic cross-linked Pec-Cel hydrogel nanobiocomposite). Based on SEM images, prepared Fe3O4 magnetic nanoparticles (MNPs) were uniformly dispersed in the Pec-Cel hydrogel context, representing an average particle size between 50.0 and 60.0 nm. The XRD pattern also confirms the crystallinity of the magnetic nanobiocomposite. All constituent elements and their distribution have been depicted in the EDX analysis of the magnetic nanobiocomposite. VSM curves confirmed the superparamagnetic behavior of Fe3O4 MNPs and the magnetic nanobiocomposite with a saturation magnetization of 77.31 emu g-1 and 48.80 emu g-1, respectively. The thermal stability of the nanobiocomposite was authenticated to ca. 800 °C based on the TGA thermogram. Apart from analyzing the structural properties of the magnetic cross-linked Pec-Cel hydrogel nanobiocomposite, different concentrations (0.5 mg mL-1, 1.0 mg mL-1, 2.0 mg mL-1, 5.0 mg mL-1, and 10.0 mg mL-1) of this new magnetic nanostructure were exposed to an alternating magnetic field (AMF) at different frequencies (100.0 MHz, 200.0 MHz, 300.0 MHz, and 400.0 MHz) to evaluate its capacity for an in vitro hyperthermia process; in addition, the highest specific absorption rate (126.0 W g-1) was obtained by the least magnetic nanobiocomposite concentration (0.5 mg mL-1).

Effect of Callus Cell Immobilization on the Textural and Rheological Properties, Loading, and Releasing of Grape Seed Extract from Pectin Hydrogels

The purpose of the present study was to prepare pectin hydrogels with immobilized Lemna minor callus cells and to identify the effect of cell immobilization on the textural, rheological, and swelling properties; loading; and releasing of grape seed extract (GSE) from the hydrogels. Hardness, adhesiveness, elasticity, the strength of linkage, and complex viscosity decreased with increasing cell content in the hydrogels based on pectin with a degree of methyl esterification (DM) of 5.7% (TVC) and during incubation in gastrointestinal fluids. An increase in the rheological properties and fragility of pectin/callus hydrogels based on pectin with a DM of 33.0% (CP) was observed at a cell content of 0.4 g/mL. TVC-based pectin/callus beads increased their swelling in gastrointestinal fluids as cell content increased. TVC-based beads released GSE very slowly into simulated gastric and intestinal fluids, indicating controlled release. The GSE release rate in colonic fluid decreased with increasing cell content, which was associated with the accumulation of GSE in cells. CP-based beads released GSE completely in the intestinal fluid due to weak textural characteristics and rapid degradation within 10 min. Pectin/callus hydrogels have the ability to preserve GSE for a long time and may have great potential for the development of proanthocyanidin delivery systems due to their novel beneficial physicochemical and textural properties.

Pectin hydrogels for controlled drug release: Recent developments and future prospects

Pectin hydrogels have emerged as a highly promising medium for the controlled release of pharmaceuticals in the dynamic field of drug delivery. The present review sheds light on the broad range of applications and potential of pectin-based hydrogels in pharmaceutical formulations. Pectin, as a biopolymer, is a versatile candidate for various drug delivery systems because of its wide range of properties and characteristics. The information provided on formulation strategies and crosslinking techniques provides researchers with tools to improve drug entrapment and controlled release. Furthermore, this review provides a more in-depth understanding of the complex factors influencing drug release from pectin hydrogels, such as the impact of environmental conditions and drug-specific characteristics. Pectin hydrogels demonstrate adaptability across diverse domains, ranging from applications in oral and transdermal drug delivery to contributions in wound healing, tissue engineering, and ongoing clinical trials. While standardization and regulatory compliance remain significant challenges, the future of pectin hydrogels appears to be bright, opening up new possibilities for advanced drug delivery systems.

Green Extraction of Pectin from Sugar Beet Flakes and Its Application in Hydrogels and Cryogels

Sugar beet flakes, a by-product of the sugar industry, were used as a source for pectin extraction that was performed using conventional citric acid extraction (CE) and two non-conventional extraction techniques-microwave-assisted extraction (MAE) and pulsed ultrasound-assisted extraction (PUAE). The influence of extraction conditions was studied for each technique based on pectin yield and galacturonic acid content, and spectroscopic, chromatographic and colorimetric methods were used for pectin characterization. Better results for pectin yield were achieved through CE (20.80%), while higher galacturonic acid content was measured in pectin extracted using PUAE (88.53 g/100 g). Pectin extracted using PUAE also presented a higher degree of methylation and acetylation. A significant increase in the molecular weight of pectin was observed for the PUAE process (7.40 × 105 g/mol) by comparison with conventional extraction (1.18 × 105 g/mol). Hydrogels and cryogels prepared with pectin from sugar beet flakes also showed differences in physicochemical parameters determined by the method of pectin extraction. Hydrogels had higher bulk density values irrespective of the pectin extraction method, and overall lower values of the textural parameters. Cryogels prepared with pectin from CE showed higher values of the textural parameters of hardness, adhesiveness, cohesiveness, gumminess and chewiness, while gels obtained with pectin from MAE and PUAE had higher thermal stability. The results of this study prove that sugar beet flakes can be considered a potential source for pectin production, and the extracted pectin is suitable for obtaining hydrogels and cryogels with physicochemical parameters comparable to the commercial citrus and apple pectin available on the market.

Design of Novel Knot-like Structures Based on Ovotransferrin Fibril-Gum Arabic Complexes: Effective Strategies to Stabilize Pickering Emulsions

This work aimed to clarify the effects of gum arabic (GA) on the morphology and properties of ovotransferrin fibrils (OVTFs). By constructing OVTF-GA complexes and exploring the dispersion stability, turbidity and the ζ-potential of the complexes, the optimum mass ratio of OVTFs to GA and pH for complex formation were confirmed as being 1:1 and pH 4.6, respectively. The interaction between OVTFs and GA was determined to be predominantly driven by electrostatic attraction. The OVTF-GA complexes exhibited a knot-like structure when observed using atomic force microscopy. Then, OVTFs and OVTF-GA complexes were compared in terms of contact angle, surface hydrophobicity and dynamic interfacial tension. The combination of OVTFs and GA decreased the contact angle of OVTFs from 80.85° to 70.36°. In comparison with OVTFs, OVTF-GA complexes reduced the oil-water interfacial tension to a lower level (8.14 mN/m). Furthermore, the capacities of OVTF-GA complexes in stabilizing emulsions were explored. OVTF-GA complex-stabilized oleogel-based Pickering emulsion (OGPE) was constructed, and OVTF-stabilized oleogel-based Pickering emulsion (OPE) was used as the control. OGPE had a higher emulsified phase volume fraction (EPVF) and stability index (SI). The EPVF of OGPE was 100.0% and 99.4% before and after one-month storage, respectively, compared with 98.3% and 95.7% of OPE. This work can provide some useful references for the design of biopolymers with novel structures composed of protein fibrils and polysaccharides, which may also help to construct and apply protein fibril-polysaccharide complexes under specific needs.