The Use of Chitosan, Alginate, and Pectin in the Biomedical and Food Sector-Biocompatibility, Bioadhesiveness, and Biodegradability

Plant-derived polyphenolic compounds: nanodelivery through polysaccharide-based systems to improve the biological properties

Plant-derived polyphenols are naturally occurring compounds widely distributed in plants. They have received greater attention in the food and pharmaceutical industries due to their potential health benefits, reducing the risk of some chronic diseases due to their antioxidant, anti-inflammatory, anticancer, cardioprotective, and neuro-action properties. Polyphenolic compounds orally administered can be used as adjuvants in several treatments but with restricted uses due to chemical instability. The review discusses the different structural compositions of polyphenols and their influence on chemical stability. Despite the potential and wide applications, there is a need to improve the delivery of polyphenolics to target the human intestine without massive chemical modifications. Oral administration of polyphenols is unfeasible due to instability, low bioaccessibility, and limited bioavailability. Nano-delivery systems based on polysaccharides (starch, pectin, chitosan, and cellulose) have been identified as a viable option for oral ingestion, potentiate biological effects, and direct-controlled delivery in specific tissues. The time and dose can be individualized for specific diseases, such as intestinal cancer. This review will address the mechanisms by which polysaccharides-based nanostructured systems can protect against degradation and enhance intestinal permeation, oral bioavailability, and the potential application of polysaccharides as nanocarriers for the controlled and targeted delivery of polyphenolic compounds.

Quaternary Ammonium Palmitoyl Glycol Chitosan (GCPQ) Loaded with Platinum-Based Anticancer Agents-A Novel Polymer Formulation for Anticancer Therapy

Quaternary ammonium palmitoyl glycol chitosan (GCPQ) has already shown beneficial drug delivery properties and has been studied as a carrier for anticancer agents. Consequently, we synthesised cytotoxic platinum(IV) conjugates of cisplatin, carboplatin and oxaliplatin by coupling via amide bonds to five GCPQ polymers differing in their degree of palmitoylation and quaternisation. The conjugates were characterised by ¹H and ¹⁹⁵Pt NMR spectroscopy as well as inductively coupled plasma mass spectrometry (ICP-MS), the latter to determine the amount of platinum(IV) units per GCPQ polymer. Cytotoxicity was evaluated by the MTT assay in three human cancer cell lines (A549, non-small-cell lung carcinoma; CH1/PA-1, ovarian teratocarcinoma; SW480, colon adenocarcinoma). All conjugates displayed a high increase in their cytotoxic activity by factors of up to 286 times compared to their corresponding platinum(IV) complexes and mostly outperformed the respective platinum(II) counterparts by factors of up to 20 times, also taking into account the respective loading of platinum(IV) units per GCPQ polymer. Finally, a biodistribution experiment was performed with an oxaliplatin-based GCPQ conjugate in non-tumour-bearing BALB/c mice revealing an increased accumulation in lung tissue. These findings open promising opportunities for further tumouricidal activity studies especially focusing on lung tissue.

A Review of Chitosan and Chitosan Nanofiber: Preparation, Characterization, and Its Potential Applications

Chitosan is produced by deacetylating the abundant natural chitin polymer. It has been employed in a variety of applications due to its unique solubility as well as its chemical and biological properties. In addition to being biodegradable and biocompatible, it also possesses a lot of reactive amino side groups that allow for chemical modification and the creation of a wide range of useful derivatives. The physical and chemical characteristics of chitosan, as well as how it is used in the food, environmental, and medical industries, have all been covered in a number of academic publications. Chitosan offers a wide range of possibilities in environmentally friendly textile processes because of its superior absorption and biological characteristics. Chitosan has the ability to give textile fibers and fabrics antibacterial, antiviral, anti-odor, and other biological functions. One of the most well-known and frequently used methods to create nanofibers is electrospinning. This technique is adaptable and effective for creating continuous nanofibers. In the field of biomaterials, new materials include nanofibers made of chitosan. Numerous medications, including antibiotics, chemotherapeutic agents, proteins, and analgesics for inflammatory pain, have been successfully loaded onto electro-spun nanofibers, according to recent investigations. Chitosan nanofibers have several exceptional qualities that make them ideal for use in important pharmaceutical applications, such as tissue engineering, drug delivery systems, wound dressing, and enzyme immobilization. The preparation of chitosan nanofibers, followed by a discussion of the biocompatibility and degradation of chitosan nanofibers, followed by a description of how to load the drug into the nanofibers, are the first issues highlighted by this review of chitosan nanofibers in drug delivery applications. The main uses of chitosan nanofibers in drug delivery systems will be discussed last.

Morin Hydrate Encapsulation and Release from Mesoporous Silica Nanoparticles for Melanoma Therapy

Melanoma incidence, a type of skin cancer, has been increasing worldwide. There is a strong need to develop new therapeutic strategies to improve melanoma treatment. Morin is a bioflavonoid with the potential for use in the treatment of cancer, including melanoma. However, therapeutic applications of morin are restrained owing to its low aqueous solubility and limited bioavailability. This work investigates morin hydrate (MH) encapsulation in mesoporous silica nanoparticles (MSNs) to enhance morin bioavailability and consequently increase the antitumor effects in melanoma cells. Spheroidal MSNs with a mean size of 56.3 ± 6.5 nm and a specific surface area of 816 m²/g were synthesized. MH was successfully loaded (MH-MSN) using the evaporation method, with a loading capacity of 28.3% and loading efficiency of 99.1%. In vitro release studies showed that morin release from MH-MSNs was enhanced at pH 5.2, indicating increased flavonoid solubility. The in vitro cytotoxicity of MH and MH-MSNs on human A375, MNT-1 and SK-MEL-28 melanoma cell lines was investigated. Exposure to MSNs did not affect the cell viability of any of the cell lines tested, suggesting that the nanoparticles are biocompatible. The effect of MH and MH-MSNs on reducing cell viability was time- and concentration-dependent in all melanoma cell lines. The A375 and SK-MEL-28 cell lines were slightly more sensitive than MNT-1 cells in both the MH and MH-MSN treatments. Our findings suggest that MH-MSNs are a promising delivery system for the treatment of melanoma.

Green Routes for Bio-Fabrication in Biomedical and Pharmaceutical Applications

In the last decade, significant advances in nanotechnologies, rising from increasing knowledge and refining of technical practices in green chemistry and bioengineering, enabled the design of innovative devices suitable for different biomedical applications. In particular, novel bio-sustainable methodologies are developing to fabricate drug delivery systems able to sagely mix properties of materials (i.e., biocompatibility, biodegradability) and bioactive molecules (i.e., bioavailability, selectivity, chemical stability), as a function of the current demands for the health market. The present work aims to provide an overview of recent developments in the bio-fabrication methods for designing innovative green platforms, emphasizing the relevant impact on current and future biomedical and pharmaceutical applications.

Application of polysaccharides for the encapsulation of beneficial microorganisms for agricultural purposes: A review

Intensive farming practices have increased the consumption of chemical-based pesticides and fertilizers thereby creating health issues for humans and animals and also causing a deterioration in the natural ecosystem. The promotion of biomaterials synthesis could potentially lead to the replacement of synthetic products and improve soil fertility, protect plants from pathogen attacks, and enhance the productivity of the agricultural sector resulting in less environmental pollution. Microbial bioengineering involving the use and improvement of encapsulation using polysaccharides has the required potential to address environmental issues and promote green chemistry. This article describes various encapsulation techniques and polysaccharides which have an immense applicable capability to encapsulate microbial cells. The review elucidates the factors that may result in a reduced viable cell count during encapsulation, particularly using the spray drying method, where a high temperature is required to dry the suspension, this may damage the microbial cells. The environmental advantage of the application of polysaccharides as carriers of beneficial microorganisms, which do not pose a risk for soil due to their full biodegradability, was also shown. The encapsulated microbial cells may assist in addressing certain environmental problems such as ameliorating the unfavourable effects of plant pests and pathogens, and promoting agricultural sustainability.

Biomimetic Scaffolds for Tendon Tissue Regeneration

Tendon tissue connects muscle to bone and plays crucial roles in stress transfer. Tendon injury remains a significant clinical challenge due to its complicated biological structure and poor self-healing capacity. The treatments for tendon injury have advanced significantly with the development of technology, including the use of sophisticated biomaterials, bioactive growth factors, and numerous stem cells. Among these, biomaterials that the mimic extracellular matrix (ECM) of tendon tissue would provide a resembling microenvironment to improve efficacy in tendon repair and regeneration. In this review, we will begin with a description of the constituents and structural features of tendon tissue, followed by a focus on the available biomimetic scaffolds of natural or synthetic origin for tendon tissue engineering. Finally, we will discuss novel strategies and present challenges in tendon regeneration and repair.

The correlation of molecule weight of chitosan oligomers with the corresponding viscosity and antibacterial activity

In order to explore the correlation between the viscosity of chitosan oligomers-acetic solution and its viscosity average molecular weight (M_v), and determine the M_v range with a strong bactericidal effect. A series of chitosan oligomers were obtained by degraded chitosan (728.5 kDa) with dilute acid and chitosan oligomer (101.5 kDa) was characterized by FT-IR, XRD, H NMR and C NMR. The bactericidal effect of chitosan oligomers with different Mv on E. coli, S. aureus and C. albicans was measured by plate counting method. And the bactericidal rate was taken as the evaluation indicator, the optimum conditions were determined by single-factor experiments. The result showed that the molecular structure of chitosan oligomers and original chitosan (728.5 kDa) were similar. The viscosity of the chitosan oligomers in acetic acid solution was positively correlated with the M_v, and the chitosan oligomers with the M_v of 52.5-145.0 kDa had a strong bactericidal performance. In addition, the bactericidal rate of chitosan oligomers on experimental strains was more than 90% when the concentration of 0.5 g/L (bacteria) and 1.0 g/L (fungi), pH6.0, incubation time of 30 min. Thus, chitosan oligomers had a potential application value when the M_v was in the range of 52.5-145.0 kDa.

Application of polyvinyl alcohol/chitosan copolymer hydrogels in biomedicine: A review

Hydrogels is a hydrophilic, cross-linked polymer of three-dimensional network structures. The application of hydrogels prepared from a single polymer in the biomedical field has many drawbacks. The functional blend of polyvinyl alcohol and chitosan allows hydrogels to have better and more desirable properties than those produced from a single polymer, which is a good biomaterial for development and design. In this paper, we have reviewed the progress in the application of polyvinyl alcohol/chitosan composite hydrogels in various medical fields, the different cross-linking agents and cross-linking methods, and the research progress in the optimization of composite hydrogels for their subsequent wide range of biomedical applications.

Improved membrane stability of alginate-chitosan microcapsules by crosslinking with tannic acid

OBJECTIVE

The insufficient stability of alginate-chitosan (ALG-CS) microcapsules in biorelevant media limits their applications in the biomedical field. Attempts were made to improve the membrane stability of ALG-CS microcapsules by noncovalent crosslinking with tannic acid.

RESULTS

The membrane stability of ALG-CS microcapsules in culture medium and serum was significantly improved by crosslinking with tannic acid. Moreover, the reason for the significant improvement in membrane stability had been demonstrated to be that the stability of chitosan-tannic acid (CS-TA) polyelectrolyte complexes was less affected by the competitive binding of those weak acid ions such as HCO₃^-. In addition, the optimal conditions for preparing alginate-chitosan-tannic acid (ALG-CS-TA) microcapsules were tannic acid concentration of 0.5% (w/v) and pH = 7.

CONCLUSION

The study provides a novel approach for improving the stability of the ALG-CS microcapsules in biorelevant media to expand their scope of application in the biological field.

A review on directional muscle cell growth in scaffolding biomaterials with aligned porous structures for cultivated meat production

Scaffolds suitable for use in food products are essential in cultured meat production. Simultaneously, efforts are being undertaken to strengthen the scaffolding to improve cell proliferation, differentiation, and tissue formation. Muscle cells proliferate and differentiate according to the directional patterns of the scaffold, similar to natural tissue and native muscle tissue. Therefore, establishing an aligned pattern in the scaffolding architecture is vital for cultured meat applications. Recent studies on the fabrication of scaffolds with aligned porosity structures and their utility in manufacturing cultured meat are highlighted in this review. In addition, the directional growth of muscle cells in terms of proliferation and differentiation has also been explored, along with the aligned scaffolding architectures. The aligned porosity architecture of the scaffolds supports the texture and quality of meat-like structures. Although it is difficult to build adequate scaffolds for culturing meat manufactured from diverse biopolymers, it is necessary to develop novel methods to create aligned scaffolding structures. Furthermore, to avoid animal slaughter in the future, it will be imperative to adopt non-animal-based biomaterials, growth factors, and serum-free media conditions for quality meat production.

Coaxial microfluidic spinning design produced high strength alginate membranes for antibacterial activity and drug release

Directional drug delivery and sufficient strength are two conditions that need to be met for wound dressing. In this paper, an oriented fibrous alginate membrane with sufficient strength was constructed via coaxial microfluidic spinning, and zeolitic imidazolate framework-8/ascorbic acid was used to realize drug delivery and antibacterial activity. The effects of the process parameters of the coaxial microfluidic spinning on the mechanical properties of the alginate membrane were discussed. In addition, it was found that the antimicrobial activity mechanism of zeolitic imidazolate framework-8 was attributed to the disruptive effect of reactive oxygen species (ROS) on bacteria, and the quantitative amount of generated ROS were evaluated by detecting •OH and H₂O₂. Furthermore, a mathematical drug diffusion model was established and showed high consistency with the experimental data (R² = 0.99). This study provides a new idea for the preparation of dressing materials with high strength and directional drug delivery and also provides some guidance for the development of coaxial microfluidic spin technology to be used in functional materials for drug release.

A 3D-Printed Biomaterial Scaffold Reinforced with Inorganic Fillers for Bone Tissue Engineering: In Vitro Assessment and In Vivo Animal Studies

This research aimed to substantiate the potential practicality of utilizing a matrix-like platform, a novel 3D-printed biomaterial scaffold, to enhance and guide host cells' growth for bone tissue regeneration. The 3D biomaterial scaffold was successfully printed using a 3D Bioplotter^® (EnvisionTEC, GmBH) and characterized. Osteoblast-like MG63 cells were utilized to culture the novel printed scaffold over a period of 1, 3, and 7 days. Cell adhesion and surface morphology were examined using scanning electron microscopy (SEM) and optical microscopy, while cell viability was determined using MTS assay and cell proliferation was evaluated using a Leica microsystem (Leica MZ10 F). The 3D-printed biomaterial scaffold exhibited essential biomineral trace elements that are significant for biological bone (e.g., Ca-P) and were confirmed through energy-dispersive X-ray (EDX) analysis. The microscopy analyses revealed that the osteoblast-like MG63 cells were attached to the printed scaffold surface. The viability of cultured cells on the control and printed scaffold increased over time (p < 0.05); however, on respective days (1, 3, and 7 days), the viability of cultured cells between the two groups was not significantly different (p > 0.05). The protein (human BMP-7, also known as growth factor) was successfully attached to the surface of the 3D-printed biomaterial scaffold as an initiator of osteogenesis in the site of the induced bone defect. An in vivo study was conducted to substantiate if the novel printed scaffold properties were engineered adequately to mimic the bone regeneration cascade using an induced rabbit critical-sized nasal bone defect. The novel printed scaffold provided a potential pro-regenerative platform, rich in mechanical, topographical, and biological cues to guide and activate host cells toward functional regeneration. The histological studies revealed that there was progress in new bone formation, especially at week 8 of the study, in all induced bone defects. In conclusion, the protein (human BMP-7)-embedded scaffolds showed higher regenerative bone formation potential (week 8 complete) compared to the scaffolds without protein (e.g., growth factor; BMP-7) and the control (empty defect). At 8 weeks postimplantation, protein (BMP-7) significantly promoted osteogenesis as compared to other groups. The scaffold underwent gradual degradation and replacement by new bones at 8 weeks in most defects.

Versatile functionalization of pectic conjugate: From design to biomedical applications

Pectin exists extensively in nature and has attracted much attention in biological applications for its unique chemical and physical characteristics. Functionalized pectin, especially pectic conjugates, has given many possibilities for pectin to improve its properties and bioactivity as well as to deliver active molecules. To better exploit this strategy of pectic functionalization, this review presents in detail the structural modifications of pectin, different synthetic methods, and design strategies of pectic conjugates involving both traditional chemical and "green" approaches. Here, the research ideas and applications of pectic prodrugs as well as the development of preparation based on pectic conjugates are reviewed, with emphasis on crosslinking systems of functionalized pectin and nanosystems based on self-assembly techniques. We hope this review will provide comprehensive and valuable information for the functionalization and systematization of the pectic conjugate from synthesis to application.

Use of whey protein as a natural polymer for the encapsulation of plant biocontrol bacteria: A review

Climate changes, drought, the salinity of water and soil, the emergence of new breeds of pests and pathogens, the industrialization of countries, and environmental contamination are among the factors limiting the production of agricultural products. The use of chemicals (in the form of fertilizers, pesticides and fungicides) to enhance products against biotic and abiotic stresses has limitations. To eliminate the effects of agricultural chemicals, synthetic agrochemicals should be replaced with natural substances and useful microorganisms. To be more effective and efficient, plant biocontrol bacteria need a coating layer around themselves to protect them from adverse conditions. Whey protein, a valuable by-product of the cheese industry, is one of the important natural polymers. Due to its high protein content, safety, and biodegradability, whey can have many applications in agriculture and encapsulation of bacteria to resist pests and plant diseases. This compound is a rich source of amino acids that can activate plant defense systems and defense enzymes. Considering the amazing potentialities of formulation whey protein, this review attends to the efficiency of whey protein as coating layers on fruit and vegetables and in the packaging system to increase the shelf life of agricultural products against phytopathogens.

The Studies on Chitosan for Sustainable Development: A Bibliometric Analysis

Chitosan is a biocompatible polymer with vast applications in pharmacology, medicine, paper making, agriculture, and the food industry due to its low toxicity. Chitosan also plays an important role in the sustainable environment since chitosan is able to absorb greenhouse gases, harmful organic matter, and heavy ions. Therefore, this paper conducts a bibliometric analysis of chitosan for sustainable development using the Scopus database from 1976 to 2023. A performance analysis on the 8002 documents was performed with Harzing's Publish or Perish. Science mapping was conducted using VOSviewer. The annual publication on chitosan for sustainable development showed an upward trend in recent years as the annual publication peaked in 2022 with 1178 documents with most of the documents being articles and published in journals. Material science, chemistry, and engineering are tightly related subject areas. China had the highest publication of 1560 total documents while the United States had the most impactful publication with 55,019 total citations, 68.77 citations per document, 77.6 citations per cited document, h-index 110, and g-index of 211. India had the largest international collaboration with 572 total link strength. "International Journal of Biological Macromolecules", "Carbohydrate Polymers", and "Polymers" have been identified as the top three source titles that publish the most documents on chitosan for sustainable development. The emerging trends in chitosan on sustainable development focus on the application of chitosan as an antibacterial agent and biosorbent for contaminants, especially in water treatment.

Vaginal Sheets with Thymbra capitata Essential Oil for the Treatment of Bacterial Vaginosis: Design, Characterization and In Vitro Evaluation of Efficacy and Safety

We aimed to incorporate Thymbra capitata essential oil (TCEO), a potent antimicrobial natural product against bacterial vaginosis (BV)-related bacteria, in a suitable drug delivery system. We used vaginal sheets as dosage form to promote immediate relief of the typical abundant vaginal discharge with unpleasant odour. Excipients were selected to promote the healthy vaginal environment reestablishment and bioadhesion of formulations, while the TCEO acts directly on BV pathogens. We characterized vaginal sheets with TCEO in regard to technological characterization, predictable in vivo performance, in vitro efficacy and safety. Vaginal sheet D.O (acid lactic buffer, gelatine, glycerine, chitosan coated with TCEO 1% w/w) presented a higher buffer capacity and ability to absorb vaginal fluid simulant (VFS) among all vaginal sheets with EO, showing one of the most promising bioadhesive profiles, an excellent flexibility and structure that allow it to be easily rolled for application. Vaginal sheet D.O with 0.32 µL/mL TCEO was able to significantly reduce the bacterial load of all in vitro tested Gardnerella species. Although vaginal sheet D.O presented toxicity at some concentrations, this product was developed for a short time period of treatment, so this toxicity can probably be limited or even reversed when the treatment ends.

The Role of Mucoadhesion and Mucopenetration in the Immune Response Induced by Polymer-Based Mucosal Adjuvants

Mucus is a viscoelastic gel that acts as a protective barrier for epithelial surfaces. The mucosal vehicles and adjuvants need to pass through the mucus layer to make drugs and vaccine delivery by mucosal routes possible. The mucoadhesion of polymer particle adjuvants significantly increases the contact time between vaccine formulations and the mucosa; then, the particles can penetrate the mucus layer and epithelium to reach mucosa-associated lymphoid tissues. This review presents the key findings that have aided in understanding mucoadhesion and mucopenetration while exploring the influence of physicochemical characteristics on mucus-polymer interactions. We describe polymer-based particles designed with mucoadhesive or mucopenetrating properties and discuss the impact of mucoadhesive polymers on local and systemic immune responses after mucosal immunization. In future research, more attention paid to the design and development of mucosal adjuvants could lead to more effective vaccines.

Platinum(IV)-Loaded Degraded Glycol Chitosan as Efficient Platinum(IV) Drug Delivery Platform

A new class of anticancer prodrugs was designed by combining the cytotoxicity of platinum(IV) complexes and the drug carrier properties of glycol chitosan polymers: Unsymmetrically carboxylated platinum(IV) analogues of cisplatin, carboplatin and oxaliplatin, namely (OC-6-44)-acetatodiammine(3-carboxypropanoato)dichloridoplatinum(IV), (OC-6-44)-acetaodiammine(3-carboxypropanoato)(cyclobutane-1,1-dicarboxylato)platinum(IV) and (OC-6-44)-acetato(3-carboxypropanoato)(1R,2R-cyclohexane-1,2-diamine)oxalatoplatinum(IV) were synthesised and conjugated via amide bonding to degraded glycol chitosan (dGC) polymers with different chain lengths (5, 10, 18 kDa). The 15 conjugates were investigated with ¹H and ¹⁹⁵Pt NMR spectroscopy, and average amounts of platinum(IV) units per dGC polymer molecule with ICP-MS, revealing a range of 1.3-22.8 platinum(IV) units per dGC molecule. Cytotoxicity was tested with MTT assays in the cancer cell lines A549, CH1/PA-1, SW480 (human) and 4T1 (murine). IC₅₀ values in the low micromolar to nanomolar range were obtained, and higher antiproliferative activity (up to 72 times) was detected with dGC-platinum(IV) conjugates in comparison to platinum(IV) counterparts. The highest cytotoxicity (IC₅₀ of 0.036 ± 0.005 µM) was determined in CH1/PA-1 ovarian teratocarcinoma cells with a cisplatin(IV)-dGC conjugate, which is hence 33 times more potent than the corresponding platinum(IV) complex and twice more potent than cisplatin. Biodistribution studies of an oxaliplatin(IV)-dGC conjugate in non-tumour-bearing Balb/C mice showed an increased accumulation in the lung compared to the unloaded oxaliplatin(IV) analogue, arguing for further activity studies.

Chitosan modified with lanthanum ions as implantable hydrogel for local delivery of bisphosphonates

Osteoporosis is a disease that affects many people around the world. One group of drugs used to treat it are bisphosphonates. However, they have poor bioavailability and many side effects. Therefore, research around the world is focused on developing bisphosphonate delivery systems. In this paper, we would like to present the design of a hydrogel material with chitosan matrix modified with lanthanum, that could serve as an implantable hydrogel capable of sustained and slow release of Zoledronate. Various research techniques were used to characterize the materials, and the swelling ratio and water solubility were also tested. The conducted research proved that the prepared hydrogel is capable of the long-term release of the Zoledronate. Thanks to this, the prepared material can be successfully used as an implantable hydrogel or a coating on titanium implants for the local delivery of drugs.

Development of engineered probiotics with tailored functional properties and their application in food science

The potential health benefits of probiotics may not be cognized because of the substantial curtailment in their viability during food storage and passage through the gastrointestinal system. Intestinal flora composition, and resistance against pathogens are among the health benefits associated with probiotic consumption. In the gastric environment, pH 2.0, probiotics dramatically lose their viability during the transit through the gastrointestinal system. The challenge remains to maintain cell viability until it reaches the large intestine. In extreme conditions, such as a decrease in pH or an increase in temperature, encapsulation technology can enhance the viability of probiotics. Probiotic bacterial strains can be encapsulated in a variety of ways. The methods are broadly systematized into two categories, liquid and solid delivery systems. This review emphasizes the technology used in the research and commercial sectors to encapsulate probiotic cells while keeping them alive and the food matrix used to deliver these cells to consumers.

Graphical abstract

Nanofibers with genotyped Bacillus strains exhibiting antibacterial and immunomodulatory activity

Biofilm-associated diseases such as periodontitis are widespread and challenging to treat which calls for new strategies for their effective management. Probiotics represent a promising approach for targeted treatment of dysbiosis in biofilm and modulation of host immune response. In this interdisciplinary study, nanofibers with two autochthonous Bacillus strains 27.3.Z and 25.2.M were developed. The strains were isolated from the oral microbiota of healthy individuals, and their genomes were sequenced and screened for genes associated with antimicrobial and immunomodulatory activities, virulence factors, and transferability of resistance to antibiotics. Spores of two Bacillus strains were incorporated individually or in combination into hydrophilic poly(ethylene oxide) (PEO) and composite PEO/alginate nanofibers. The nanofiber mats were characterised by a high loading of viable spores (> 7 log CFU/mg) and they maintained viability during electrospinning and 6 months of storage at room temperature. Spores were rapidly released from PEO nanofibers, while presence of alginate in the nanofibers prolonged their release. All formulations exhibited swelling, followed by transformation of the nanofiber mat into a hydrogel and polymer erosion mediating spore release kinetics. The investigated Bacillus strains released metabolites, which were not cytotoxic to peripheral blood mononuclear cells (PBMCs) in vitro. Moreover, their metabolites exhibited antibacterial activity against two periodontopathogens, an antiproliferative effect on PBMCs, and inhibition of PBMC expression of proinflammatory cytokines. In summary, the developed nanofiber-based delivery system represents a promising therapeutic approach to combat biofilm-associated disease on two fronts, namely via modulation of the local microbiota with probiotic bacteria and host immune response with their metabolites.

Encapsulating biocontrol bacteria with starch as a safe and edible biopolymer to alleviate plant diseases: A review

Healthy foods with few artificial additives are in high demand among consumers. Preserving conventional pesticides, frequently used as chemicals to control phytopathogens, is challenging. Therefore, we proposed an innovative approach to protect agricultural products in this review. Biocontrol bacteria are safe alternatives with low stability and low efficiency in the free-form formulation. The encapsulation technique for covering active compounds (e.g., antimicrobials) represents a more efficient protection technology because encapsulation causes the controlled release of bioactive materials and reduces the application doses. Of the biopolymers able to form a capsule, starch exhibits several advantages, such as its ready availability, cost-effectively, edible, colorless, and tasteless. Nevertheless, the poor mechanical properties of starch can be improved with other edible biopolymers. In addition, applying formulations incorporated with more than one antimicrobial material offers synergistic effects. This review presented the starch-based capsules used to enclose antimicrobial agents as effective tools against phytopathogens.

Preparation and In Vitro Evaluation of Chitosan-g-Oligolactide Based Films and Macroporous Hydrogels for Tissue Engineering

In the current study, novel matrices based on chitosan-g-oligo (L,L-/L,D-lactide) copolymers were fabricated. In particular, 2D films were prepared by solvent casting, while 3D macroporous hydrogels were obtained by lyophilization of copolymer solutions. Copolymers of chitosan (Chit) with semi-crystalline oligo (L,L-lactide) (Chit-LL) or amorphous oligo (L,D-lactide) (Chit-LD) were obtained by solid-state mechanochemical synthesis. The structure of the hydrogels was found to be a system of interconnected macropores with an average size of 150 μm. In vitro degradation of these copolymer-based matrices was shown to increase in the case of the Chit-LL-based hydrogel by 34% and decrease for the Chit-LD-based hydrogel by 23% compared to the parameter of the Chit sample. Localization and distribution of mouse fibroblast L929 cells and adipose tissue-derived mesenchymal stromal cells (MSCs) within the hydrogels was studied by confocal laser scanning microscopy (CLSM). Moreover, cellular response, namely cell adhesion, spreading, growth, proliferation, as well as cell differentiation in vitro were also evaluated in the hydrogels for 10-14 days. Both the Chit-LL and Chit-LD matrices were shown to support cell growth and proliferation, while they had improved swelling compared to the Chit matrix. Osteogenic MSCs differentiation on the copolymer-based films was studied by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR). Maximal expression levels of osteogenesis markers (alkaline phosphatase (ALPL), bone transcription factor (Runx2), and osteopontin (SPP1) were revealed for the Chit-LD films. Thus, osteodifferentiation was demonstrated to depend on the film composition. Both Chit-LL and Chit-LD copolymer-based matrices are promising for tissue engineering.

A Sustainable Solution to Skin Diseases: Ecofriendly Transdermal Patches

Skin is the largest epithelial surface of the human body, with a surface area of 2 m2 for the average adult human. Being an external organ, it is susceptible to more than 3000 potential skin diseases, including injury, inflammation, microbial and viral infections, and skin cancer. Due to its nature, it offers a large accessible site for administrating several medications against these diseases. The dermal and transdermal delivery of such medications are often ensured by utilizing dermal/transdermal patches or microneedles made of biocompatible and biodegradable materials. These tools provide controlled delivery of drugs to the site of action in a rapid and therapeutically effective manner with enhanced diffusivity and minimal side effects. Regrettably, they are usually fabricated using synthetic materials with possible harmful environmental effects. Manufacturing such tools using green synthesis routes and raw materials is hence essential for both ecological and economic sustainability. In this review, natural materials including chitosan/chitin, alginate, keratin, gelatin, cellulose, hyaluronic acid, pectin, and collagen utilized in designing ecofriendly patches will be explored. Their implementation in wound healing, skin cancer, inflammations, and infections will be discussed, and the significance of these studies will be evaluated with future perspectives.

Chitosan and Pectin Hydrogels for Tissue Engineering and In Vitro Modeling

Hydrogels are fascinating biomaterials that can act as a support for cells, i.e., a scaffold, in which they can organize themselves spatially in a similar way to what occurs in vivo. Hydrogel use is therefore essential for the development of 3D systems and allows to recreate the cellular microenvironment in physiological and pathological conditions. This makes them ideal candidates for biological tissue analogues for application in the field of both tissue engineering and 3D in vitro models, as they have the ability to closely mimic the extracellular matrix (ECM) of a specific organ or tissue. Polysaccharide-based hydrogels, because of their remarkable biocompatibility related to their polymeric constituents, have the ability to interact beneficially with the cellular components. Although the growing interest in the use of polysaccharide-based hydrogels in the biomedical field is evidenced by a conspicuous number of reviews on the topic, none of them have focused on the combined use of two important polysaccharides, chitosan and pectin. Therefore, the present review will discuss the biomedical applications of polysaccharide-based hydrogels containing the two aforementioned natural polymers, chitosan and pectin, in the fields of tissue engineering and 3D in vitro modeling.

Significantly improved antifouling capability of silicone rubber surfaces by covalently bonded acrylated agarose towards biomedical applications

Bacteria have the extraordinary ability to adhere to biomaterial surfaces and form multicellular structures known as biofilms, which have a detrimental impact on the performance of medical devices. Herein, an investigation highlighted the effective inhibition of bacteria adhesion and overgrowth on silicone rubber surface by grafting polysaccharide, agarose (AG), to construct hydrophilic and negatively charged surfaces. Because of the strong hydration capacity of agarose, the water contact angle of the modified silicone rubber surfaces was significantly reduced from 107.6 ± 2.7° to 19.3 ± 2.6°, which successfully limited bacterial adherence. Most importantly, the durability and stability of coating were observed after 10 days of simulated dynamic microenvironment in vivo, exhibiting a long service life. This modification method did not compromise biocompatibility of silicone rubber, opening a door to new applications for silicone rubber in the field of biomedical materials.

Recent advances in the medical applications of hemostatic materials

Bleeding caused by trauma or surgery is a serious health problem, and uncontrollable bleeding can result in death. Therefore, developing safe, effective, and convenient hemostatic materials is important. Active hemostatic agents currently used to investigate the field of hemostasis are divided into four broad categories: natural polymers, synthetic polymers, inorganic materials, and metal-containing materials. Hemostatic materials are prepared in various forms for wound care applications based on the active ingredients used. These materials include nanofibers, gels, sponges, and nanoparticles. Hemostatic materials find their applications in the field of wound care, and they are also used for hemostasis during malignant tumor surgery. Prompt and effective hemostasis can reduce the possibility of the spread of tumor cells with blood. This review discusses the outcomes of current research conducted in the field and the problems persisting in the field of developing hemostatic materials. The review also presents a platform for the further development of hemostatic materials. Bleeding caused by trauma or surgery is a serious health problem, and uncontrollable bleeding can result in death. Therefore, developing safe, effective, and convenient hemostatic materials is important. Active hemostatic agents currently used to investigate the field of hemostasis are divided into four broad categories: natural polymers, synthetic polymers, inorganic materials, and metal-containing materials. Hemostatic materials are prepared in various forms for wound care applications based on the active ingredients used. These materials include nanofibers, gels, sponges, and nanoparticles. Hemostatic materials find their applications in the field of wound care, and they are also used for hemostasis during malignant tumor surgery. Prompt and effective hemostasis can reduce the possibility of the spread of tumor cells with blood. This review discusses the outcomes of current research conducted in the field and the problems persisting in the field of developing hemostatic materials. The review also presents a platform for the further development of hemostatic materials.

Engineering multifunctional bioactive citrate-based biomaterials for tissue engineering

Developing bioactive biomaterials with highly controlled functions is crucial to enhancing their applications in regenerative medicine. Citrate-based polymers are the few bioactive polymer biomaterials used in biomedicine because of their facile synthesis, controllable structure, biocompatibility, biomimetic viscoelastic mechanical behavior, and functional groups available for modification. In recent years, various multifunctional designs and biomedical applications, including cardiovascular, orthopedic, muscle tissue, skin tissue, nerve and spinal cord, bioimaging, and drug or gene delivery based on citrate-based polymers, have been extensively studied, and many of them have good clinical application potential. In this review, we summarize recent progress in the multifunctional design and biomedical applications of citrate-based polymers. We also discuss the further development of multifunctional citrate-based polymers with tailored properties to meet the requirements of various biomedical applications.

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Multifunctional bioactive citrate-based biomaterials have broad applications in regenerative medicine.

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Recent advances in multifunctional design and biomedical applications of citate-based polymers are summarized.

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Future challenge of citrate-based polymers in various biomedical applications are discussed.

Chitin and chitin-based biomaterials: A review of advances in processing and food applications

Chitin is the most abundant natural amino polysaccharide, showing various practical applications owing to its functional properties. However, there are barriers in the development due to the difficulty of chitin extraction and purification, regarding its high crystallinity and low solubility. In recent years, some novel technologies such as microbial fermentation, ionic liquid, electrochemical extraction have emerged for the green extraction of chitin from new sources. Furthermore, nanotechnology, dissolution systems and chemical modification were applied to develop a variety of chitin-based biomaterials. Remarkably, chitin was used in delivering active ingredients and developing functional foods for weight loss, lipid reduction, gastrointestinal health, and anti-aging. Moreover, the application of chitin-based materials was expanded into medicine, energy and the environment. This review outlined the emerging extraction methods and processing routes of different chitin sources and advances in applying chitin-based materials. We aimed to provide some direction for the multi-disciplinary production and application of chitin.

Alginate-Chitosan Hydrogel Formulations Sustain Baculovirus Delivery and VEGFA Expression Which Promotes Angiogenesis for Wound Dressing Applications

Hydrogel wound dressings are effective in their ability to provide a wound-healing environment but are limited by their ability to promote later stages of revascularization. Here, a biosafe recombinant baculovirus expressing VEGFA tagged with EGFP is encapsulated in chitosan-coated alginate hydrogels using ionic cross-linking. The VEGFA, delivered by the baculovirus, significantly improves cell migration and angiogenesis to assist with the wound-healing process and revascularization. Moreover, the hydrogels have an encapsulation efficiency of 99.9%, no cytotoxicity, antimicrobial properties, good blood compatibility, promote hemostasis, and enable sustained delivery of baculoviruses over eight days. These hydrogels sustain baculovirus delivery and may have clinical implications in wound dressings or future gene therapy applications.

Transformation of theranostic alginate-based microbubbles from raspberry-like to core-shell-like microbubbles and in vitro studies

In this study alginate-based microbubbles with a raspberry-like or core-shell-like morphology and with an average particle size of 553.6 ± 69.6 μm were synthesized; this was done through a novel procedure of transforming the structure with a 40 kHz ultrasonication which also stimulated the release of the components inside. Through the use of the electrospray technique in conjunction with agitation processes, components such as shikonin (SHK) and indocyanine green (ICG) were simultaneously encapsulated in alginate microbubbles to produce SHK-ICG alginate microbubbles; these microbubbles had half-maximal inhibitory concentrations of approximately 2.08 and 4.43 μM toward CP70 and SKOV3 ovarian cancer-cell lines, respectively, in an in vitro cell model. Moreover, these SHK-ICG alginate microbubbles enhanced brightness by 2.5 fold in ultrasound imaging relative to CaCl2 medium only. In conclusion, SHK-ICG alginate microbubbles have promise for use in theranostics.

Drug Delivery Systems and Flavonoids: Current Knowledge in Melanoma Treatment and Future Perspectives

Melanoma is an aggressive form of skin cancer with a high prevalence in the population. An early diagnosis is crucial to cure this disease. Still, when this is not possible, combining potent pharmacological agents and effective drug delivery systems is essential to achieve optimal treatment and improve patients' quality of life. Nanotechnology application in biomedical sciences to encapsulate anticancer drugs, including flavonoids, in order to enhance therapeutic efficacy has attracted particular interest. Flavonoids have shown effectiveness against various types of cancers including in melanoma, but they show low aqueous solubility, low stability and very poor oral bioavailability. The utilization of novel drug delivery systems could increase flavonoid bioavailability, thereby potentiating its antitumor effects in melanoma. This review summarizes the potential of different flavonoids in melanoma treatment and the several nanosystems used to improve their biological activity, considering published information that reported improved biological and pharmacological properties of encapsulated flavonoids.

Potential of pectin for biomedical applications: a comprehensive review

Pectin is a polysaccharide extracted from various plants, such as apples, oranges, lemons, and it possesses some beneficial effects on human health, including being hypoglycemic and hypocholesterolemic. Therefore, pectin is used in various pharmaceutical and biomedical applications. Meanwhile, its low mechanical strength and fast degradation rate limit its usage as drug delivery devices and tissue engineering scaffolds. To enhance these properties, it can be modified or combined with other organic molecules or polymers and/or inorganic compounds. These materials can be prepared as nano sized drug carriers in the form of spheres, capsules, hydrogels, self assamled micelles, etc., for treatment purposes (mostly cancer). Different composites or blends of pectin can also be produced as membranes, sponges, hydrogels, or 3D printed matrices for tissue regeneration applications. This review is concentrated on the properties of pectin based materials and focus especially on the utilization of these materials as drug carriers and tissue engineering scaffolds, including 3D printed and 3D bioprinted systems covering the studies in the last decade and especially in the last 5 years.

Recent Advances of Chitosan Formulations in Biomedical Applications

Chitosan, a naturally abundant cationic polymer, is chemically composed of cellulose-based biopolymers derived by deacetylating chitin. It offers several attractive characteristics such as renewability, hydrophilicity, biodegradability, biocompatibility, non-toxicity, and a broad spectrum of antimicrobial activity towards gram-positive and gram-negative bacteria as well as fungi, etc., because of which it is receiving immense attention as a biopolymer for a plethora of applications including drug delivery, protective coating materials, food packaging films, wastewater treatment, and so on. Additionally, its structure carries reactive functional groups that enable several reactions and electrochemical interactions at the biomolecular level and improves the chitosan’s physicochemical properties and functionality. This review article highlights the extensive research about the properties, extraction techniques, and recent developments of chitosan-based composites for drug, gene, protein, and vaccine delivery applications. Its versatile applications in tissue engineering and wound healing are also discussed. Finally, the challenges and future perspectives for chitosan in biomedical applications are elucidated.

Preparation and Characteristics of Alginate Microparticles for Food, Pharmaceutical and Cosmetic Applications

Alginates are the most widely used natural polymers in the pharmaceutical, food and cosmetic industries. Usually, they are applied as a thickening, gel-forming and stabilizing agent. Moreover, the alginate-based formulations such as matrices, membranes, nanospheres or microcapsules are often used as delivery systems. Alginate microparticles (AMP) are biocompatible, biodegradable and nontoxic carriers, applied to encapsulate hydrophilic active substances, including probiotics. Here, we report the methods most frequently used for AMP production and encapsulation of different actives. The technological parameters important in the process of AMP preparation, such as alginate concentration, the type and concentration of other reagents (cross-linking agents, oils, emulsifiers and pH regulators), agitation speed or cross-linking time, are reviewed. Furthermore, the advantages and disadvantages of alginate microparticles as delivery systems are discussed, and an overview of the active ingredients enclosed in the alginate carriers are presented.

Chitosan-alginate nanoparticles of cabazitaxel: Design, dual-receptor targeting and efficacy in lung cancer model

Cabazitaxel (CZT) loaded chitosan-alginate based (CSA) nanoparticles were developed with dual targeting functions of both folate receptor and epidermal growth factor receptor (EGFR) using ionic gelation technique. The chitosan-folate conjugate was synthesized, and characterized by using FTIR, NMR and Mass spectroscopy. The physicochemical parameters and morphology of all CSA nanoparticles were examined. The degree of conjugation of folic acid and cetuximab (CTXmab) was determined by UV-Visible spectroscopy and Bradford assay, respectively. Moreover, XPS analysis also supported the presence of the ligands on nanoparticles. The cellular-uptake study performed on A-549 cells demonstrated a significant enhancement in the uptake of dual-receptor targeted CSA nanoparticles than non-targeted and single-receptor targeted CSA nanoparticles. Further, CZT-loaded dual receptors targeted CSA nanoparticles also showed significantly lower IC₅₀ values (~38 folds) than the CZT control against A-549 cells. Further, in-vivo histopathological evaluations of dual receptor-targeted CSA nanoparticles have demonstrated better safety in Wistar rats. Moreover, its treatment on the Benzo(a)pyrene (B(a)P) induced lung cancer mice model has showed the enhanced anticancer efficacy of CZT with a prolonged survival rate.

Current Advancements in Pectin: Extraction, Properties and Multifunctional Applications

Pectin is a heterogeneous hydrocolloid present in the primary cell wall and middle lamella in all dicotyledonous plants, more commonly in the outer fruit coat or peel as compared to the inner matrix. Presently, citrus fruits and apple fruits are the main sources for commercial extraction of pectin, but ongoing research on pectin extraction from alternate fruit sources and fruit wastes from processing industries will be of great help in waste product reduction and enhancing the production of pectin. Pectin shows multifunctional applications including in the food industry, the health and pharmaceutical sector, and in packaging regimes. Pectin is commonly utilized in the food industry as an additive in foods such as jams, jellies, low calorie foods, stabilizing acidified milk products, thickener and emulsifier. Pectin is widely used in the pharmaceutical industry for the preparation of medicines that reduce blood cholesterol level and cure gastrointestinal disorders, as well as in cancer treatment. Pectin also finds use in numerous other industries, such as in the preparation of edible films and coatings, paper substitutes and foams. Due to these varied uses of pectin in different applications, there is a great necessity to explore other non-conventional sources or modify existing sources to obtain pectin with desired quality attributes to some extent by rational modifications of pectin with chemical and enzymatic treatments.

Loading and Release of Phenolic Compounds Present in Mexican Oregano (Lippia graveolens) in Different Chitosan Bio-Polymeric Cationic Matrixes

Mexican oregano (Lippia graveolens) polyphenols have antioxidant and anti-inflammatory potential, but low bioaccessibility. Therefore, in the present work the micro/nano-encapsulation of these compounds in two different matrixes of chitosan (CS) and chitosan-b-poly(PEGMA2000) (CS-b-PPEGMA) is described and assessed. The particle sizes of matrixes of CS (~955 nm) and CS-b-PPEGMA (~190 nm) increased by 10% and 50%, respectively, when the phenolic compounds were encapsulated, yielding loading efficiencies (LE) between 90–99% and 50–60%, correspondingly. The release profiles in simulated fluids revealed a better control of host–guest interactions by using the CS-b-PPEGMA matrix, reaching phenolic compounds release of 80% after 24 h, while single CS retained the guest compounds. The total reducing capacity (TRC) and Trolox equivalent antioxidant capacity (TEAC) of the phenolic compounds (PPHs) are protected and increased (more than five times) when they are encapsulated. Thus, this investigation provides a standard encapsulation strategy and relevant results regarding nutraceuticals stabilization and their improved bioaccessibility.

Development of Pectin and Poly(vinyl alcohol)-Based Active Packaging Enriched with Itaconic Acid and Apple Pomace-Derived Antioxidants

The production of active and biodegradable packaging materials is an emerging and efficient alternative to plastic packaging materials. By combining poly(vinyl alcohol) (PVA), pectin, and itaconic acid (IA), biodegradable and water-soluble packaging materials can be obtained that can also increase the shelf-life and quality of foodstuff. In the present study, the generated film-forming solutions were enriched with organic or phenolic extracts from apple by-products (apple pomace). These extracts possess an efficient antioxidant activity of 9.70 ± 0.08, and 78.61 ± 0.24 μM Trolox/100 g fresh weight, respectively. Furthermore, the lyophilization of these by-products increased the extract’s organic and phenolic content and the antioxidant activity to 67.45 ± 0.28 and 166.69 ± 0.47 μM Trolox/100 g fresh weight, respectively. These extracts influence the physical-chemical properties of the biofilm solutions by facilitating the polymerization process and thus positively influencing their viscosity. The resulting biofilms presented low water vapor permeability and reduced solubility in water. Adding IA and organic/phenolic compounds facilitates the resistance against intrinsic and extrinsic factors; therefore, they might be applicable in the food industry.

Nanoencapsulation of Acetamiprid by Sodium Alginate and Polyethylene Glycol Enhanced Its Insecticidal Efficiency

Nanoformulation has been considered one of the newly applied methods in integrated pest management strategies. In this research, a conventional neonicotinoid insecticide acetamiprid was nanoencapsulated via AL (Sodium Alginate) and PEG (Polyethylene Glycol) and tested against the elm leaf beetle Xanthogaleruca luteola. The synthesized particles had spherical-like morphology and nanoscale based on TEM (Transmission Electron Microscopy) and DLS (Dynamic Light Scattering). The encapsulation efficiency and loading percentages of acetamiprid in AL and PEG were 92.58% and 90.15%, and 88.46% and 86.79%, respectively. Leaf discs treated with different formulations by the leaf-dipping method were used for oral toxicity assays. The LC₅₀ values (Lethal Concentration to kill 50% of insect population) of acetamiprid and Al- and PEG-nanoencapsulated formulations on third-instar larvae were 0.68, 0.04, and 0.08 ppm, respectively. Based on the highest relative potency, AL-encapsulated acetamiprid had the most toxicity. The content of energy reserve protein, glucose, and triglyceride and the activity of detoxifying enzymes esterase and glutathione S-transferase of the larvae treated by LC₅₀ values of nanoformulations were also decreased. According to the current findings, the nanoencapsulation of acetamiprid by Al and PEG can increase its insecticidal performance in terms of lethal and sublethal toxicity.

In Vitro Release of Anthocyanins from Microencapsulated Natal Plum (Carissa macrocarpa) Phenolic Extract in Alginate/Psyllium Mucilage Beads

Natal plum (Carissa macrocarpa) contains anthocyanins, cyanidin 3-O-β-sambubioside (Cy-3-Sa), and cyanidin 3-O-glucoside (Cy-3-G) that possess great bioactive properties. During in vitro gastrointestinal digestion, Cy-3-Sa and Cy-3-G are highly sensitive to pH changes and have low bioaccessibility rates of 7.9% and 22%, respectively. This study aimed to therefore use microencapsulation techniques to improve the bioaccessibility of Cy-3-Sa and Cy-3-G. The crude anthocyanin-rich extract was extracted from freeze-dried Natal plum fruit using ultrasonic-assisted ethanol extraction. The anthocyanin-rich extract was encapsulated using the ionic gelation method. Four distinct carrier agents, namely sodium alginate, pectin, xanthan gum and psyllium mucilage were used to form the wall materials. Encapsulation efficiency was highest for alginate/psyllium mucilage beads (93.67%), while alginate showed the least efficiency (86.80%). Scanning Electron Microscopy revealed a cracked and porous structure for the Natal plum extract and a continuous smooth structure for all the beads. Fourier transform infrared spectroscopy showed peaks at 3300 and 1610 cm⁻¹, confirming the presence of polyphenols and polysaccharides in all beads. Thermal stability was higher for the alginate/psyllium mucilage beads and the observed thermal transitions were due to the bonds formed between the polymers and the polyphenols. Alginate beads combined with xanthan gum, pectin, and psyllium mucilage showed a prolonged release of anthocyanins compared to alginate in vitro alone. The highest anthocyanin bioaccessibility was obtained from alginate/psyllium mucilage beads (85.42 ± 1.03%). The results showed the effectiveness of alginate/psyllium mucilage beads in improving stability and in vitro anthocyanin release.

Progress in Research of Chitosan Chemical Modification Technologies and Their Applications

Chitosan, which is derived from chitin, is the only known natural alkaline cationic polymer. Chitosan is a biological material that can significantly improve the living standard of the country. It has excellent properties such as good biodegradability, biocompatibility, and cell affinity, and has excellent biological activities such as antibacterial, antioxidant, and hemostasis. In recent years, the demand has increased significantly in many fields and has huge application potential. Due to the poor water solubility of chitosan, its wide application is limited. However, chemical modification of the chitosan matrix structure can improve its solubility and biological activity, thereby expanding its application range. The review covers the period from 1996 to 2022 and was elaborated by searching Google Scholar, PubMed, Elsevier, ACS publications, MDPI, Web of Science, Springer, and other databases. The various chemical modification methods of chitosan and its main activities and application research progress were reviewed. In general, the modification of chitosan and the application of its derivatives have had great progress, such as various reactions, optimization of conditions, new synthetic routes, and synthesis of various novel multifunctional chitosan derivatives. The chemical properties of modified chitosan are usually better than those of unmodified chitosan, so chitosan derivatives have been widely used and have more promising prospects. This paper aims to explore the latest progress in chitosan chemical modification technologies and analyze the application of chitosan and its derivatives in various fields, including pharmaceuticals and textiles, thus providing a basis for further development and utilization of chitosan.

Polysaccharide-Based Edible Gels as Functional Ingredients: Characterization, Applicability, and Human Health Benefits

Nowadays, edible materials such as polysaccharides have gained attention due to their valuable attributes, especially gelling property. Polysaccharide-based edible gels (PEGs) can be classified as (i) hydrogels, (ii) oleogels and bigels, (iii) and aerogels, cryogels and xerogels, respectively. PEGs have different characteristics and benefits depending on the functional groups of polysaccharide chains (e.g., carboxylic, sulphonic, amino, methoxyl) and on the preparation method. However, PEGs are found in the incipient phase of research and most studies are related to their preparation, characterization, sustainable raw materials, and applicability. Furthermore, all these aspects are treated separately for each class of PEG, without offering an overview of those already obtained PEGs. The novelty of this manuscript is to offer an overview of the classification, definition, formulation, and characterization of PEGs. Furthermore, the applicability of PEGs in the food sector (e.g., food packaging, improving food profile agent, delivery systems) and in the medical/pharmaceutical sector is also critically discussed. Ultimately, the correlation between PEG consumption and polysaccharides properties for human health (e.g., intestinal microecology, "bridge effect" in obesity, gut microbiota) are critically discussed for the first time. Bigels may be valuable for use as ink for 3D food printing in personalized diets for human health treatment. PEGs have a significant role in developing smart materials as both ingredients and coatings and methods, and techniques for exploring PEGs are essential. PEGs as carriers of bioactive compounds have a demonstrated effect on obesity. All the physical, chemical, and biological interactions among PEGs and other organic and inorganic structures should be investigated.

Natural Polysaccharide-Based Nanodrug Delivery Systems for Treatment of Diabetes

In recent years, natural polysaccharides have been considered as the ideal candidates for novel drug delivery systems because of their good biocompatibility, biodegradation, low immunogenicity, renewable source and easy modification. These natural polymers are widely used in the designing of nanocarriers, which possess wide applications in therapeutics, diagnostics, delivery and protection of bioactive compounds or drugs. A great deal of studies could be focused on developing polysaccharide nanoparticles and promoting their application in various fields, especially in biomedicine. In this review, a variety of polysaccharide-based nanocarriers were introduced, including nanoliposomes, nanoparticles, nanomicelles, nanoemulsions and nanohydrogels, focusing on the latest research progress of these nanocarriers in the treatment of diabetes and the possible strategies for further study of polysaccharide nanocarriers.