Fabrication and characterization of Chrysin - A plant polyphenol loaded alginate -chitosan composite for wound healing application

How the combination of alginate and chitosan can fabricate a hydrogel with favorable properties for wound healing

Wound management has always been a significant concern, particularly for men, and the search for effective wound dressings has led to the emergence of hydrogels as a promising solution. In recent years, hydrogels, with their unique properties, have gained considerable importance in wound management. Among the various types of hydrogels, those incorporating chitosan and alginate, two distinct chemical materials, have shown potential in accelerating wound healing. This review aims to discuss the desirable characteristics of an effective wound dressing, explore the alginate/chitosan-based hydrogels developed by different researchers, and analyze their effects on wound healing through in vitro and in vivo assessments. In vitro tests encompass a wide range of evaluations, including swelling capacity, degradation rate, porosity, Fourier Transform Infrared Spectroscopy, X-ray diffraction analysis, moisture vapor transmission rate, release studies, mechanical properties, microscopic observation, antibacterial properties, compatibility assessment, cell adhesion investigation, blood clotting capability, cell migration analysis, water contact angle determination, and structural stability. Furthermore, in vivo assessments encompass the examination of wound closure rate, modulation of gene expression, as well as histopathological and immunohistochemical studies.

Biocompatible arabinogalactan-chitosan scaffolds for photothermal pharmacology in wound healing and tissue regeneration

Delayed wound healing is often caused by bacterial infections and persistent inflammation. Multifunctional materials with anti-bacterial, anti-inflammatory, and hemostatic properties are crucial for accelerated wound healing. In this study, we report a biomacromolecule-based scaffold (ArCh) by uniquely combining arabinogalactan (Ar) and chitosan (Ch) using a Schiff-based reaction. Further, the optimized ArCh scaffolds were loaded with Glycyrrhizin (GA: anti-inflammatory molecule) conjugated NIR light-absorbing Copper sulfide (CuS) nanoparticles. The resultant GACuS ArCh scaffolds were characterized for different wound healing parameters in in-vitro and in-vivo models. Our results indicated that GACuS ArCh scaffolds showed excellent swelling, biodegradation, and biocompatibility in vitro. Further results obtained indicated that GACuS ArCh scaffolds demonstrated mild hyperthermia and enhanced hemostatic, anti-oxidant, anti-bacterial, and wound-healing effects when exposed to NIR light. The scaffolds, upon further validation, may be beneficial in accelerating wound healing and tissue regeneration response.

Study of the degradation in an ultisol of alginate-chitosan complex and its stability and applicability as a soil conditioner

The present work describes the process of degradation of a polyelectrolytic complex (PEC) based on sodium alginate (ALG) and chitosan (CHI), buried for different time intervals, in a clayey soil (ultisol) collected from the municipality of Campos dos Goytacazes, in the northern region of the state of Rio de Janeiro, Brazil. The influence of PEC on soil moisture was also investigated. The results showed that soil moisture increased with the presence of PEC after 7 days of testing, and remained high until the end of the study. FTIR and Raman spectra showed that the breaking of the glycosidic bond (C-O-C) was responsible for the PEC degradation. Thermogravimetry results revealed that alginate was possibly degraded faster than chitosan. Microscopic analysis of the PEC revealed a fragile and fragmented surface of the samples that were buried, in comparison with those not buried. The microbiological assays of the soil confirmed the biodegradation of the polysaccharides. Chemical analysis of soil indicated that PEC did not significantly influence soil fertility. Therefore, we conclude that the PEC (ALG: CHI), formed only by electrostatic interaction, buried in clayey soil, even being biodegraded, can be a promising soil conditioner for agricultural applications.

Chrysin loaded polycaprolactone-chitosan electrospun nanofibers as potential antimicrobial wound dressing

In this study, various concentrations of chrysin (chry) were loaded into polycaprolactone-chitosan (PCL-CTS) nanofibers to develop a potential wound dressing materials using electrospinning method. The structural composition and the morphology of the produced PCL-CTS5, PCL-CTS10 and PCL-CTS15 were analyzed by FE-SEM and FTIR, respectively. By increasing the amount of chry, the average diameter of the nanofibres was also increased to 191 ± 65 nm, 203 ± 72 nm, and 313 ± 69 nm for PCL-CTS5, PCL-CTS10, and PCL-CTS15, respectively. Moreover, the physicochemical characteristics and biological properties of synthesized nanofibers such as tensile testing, in-vitro drug release, porosity, decomposition rate, water absorption rate, water vapor permeability rate, cell viability, antioxidant and antibacterial activity were evaluated. By using Korsmeyer-Peppas and Higuchi kinetic models, the chry release mechanism in all nanofibers was studied in PBS solution, which suggested a Fick's diffusion. In-vitro antioxidant experiments by DPPH assay indicated 24, 43, 61 and 78 % free radical scavenging activity for PCL-CTS, PCL-CTS5, PCL-CTS10 and PCL-CTS15. In-vitro antibacterial examination showed that chry-loaded nanofibers had high antibacterial activity in which were comparable with the standard reagents. In-vitro cytotoxicity results obtained by MTT assay indicated a desired cytocompatibility towards fibroblast cells.

Effects of a chitosan nanoparticles encapsulation on the properties of litchi polyphenols

Litchi polyphenols have very specific biological activities. Nevertheless, the low and inconsistent oral bioavailability and instability hinder the further application of litchi polyphenols in food systems. This work prepared litchi polyphenols loaded chitosan nanoparticles (LP-CSNPs) by ionic gelation method to enhance the encapsulation on the properties of litchi polyphenols. The optimum conditions of formation via single factors and the Box-Behnken design were chitosan (CS) concentration 1.065 mg/mL, sodium tripolyphosphate (TPP) concentration 0.975 mg/mL, and the mass ratios of polyphenols and CS 1:1 with encapsulation efficiency (EE%) of 45.53%. LP-CSNPs presented the nanosized range of particle size (mean 170 nm), excellent polydispersity index (PDI) (0.156 ± 0.025), and zeta potential values (+ 35.44 ± 0.59). The in vitro release in simulated gastric fluid (pH 1.2) and intestinal fluid (pH 6.8) during 100 h was 58.34% and 81.68%, respectively. LP-CSNPs could effectively improve the storage stability and had great antibacterial activity compared with unencapsulated litchi polyphenols.

The Amorphous Solid Dispersion of Chrysin in Plasdone® S630 Demonstrates Improved Oral Bioavailability and Antihyperlipidemic Performance in Rats

Chrysin is a flavonoid with various biological activities. However, its low water solubility and strong metabolism render its oral bioavailability rather poor. This study aimed to develop a stable solid dispersion formulation of chrysin to improve the dissolution of chrysin, so as to increase its oral bioavailability and improve its antihyperlipidemic activities. A solid dispersion of chrysin was prepared using a solvent evaporation method, with Plasdone® S630 as the hydrophilic carrier. The formulations were characterized via X-ray diffraction, in vitro dissolution studies, and stability studies. An in-situ perfusion model was used to evaluate the absorption rates. Plasma pharmacokinetics and antihyperlipidemic performance after the oral administration of the chrysin formulations were investigated in rats. It was found that the solid dispersion of chrysin prepared using the drug-polymer mass ratio of 1:6 can form the optimized formulation. X-ray diffraction results showed that the chrysin was in an amorphous state in this optimized formulation. The cumulative release percentage of the optimized solid dispersion of chrysin at pH 1.2 and pH 6.8 was elevated to above 90% within 24 h, indicating that the formulation could enhance the dissolution rates of chrysin. Stability studies showed that the optimized formulation presented acceptable long-term storage stability, but it was susceptible to high temperature and humidity. The solid dispersion of chrysin showed higher absorption rates in the in-situ perfusion model. Pharmacokinetic studies revealed that Cmax and AUC after the intragastric administration of solid dispersion of chrysin were appreciably higher than those resulting from chrysin suspension. The oral bioavailability of the solid dispersion of chrysin was 41 times higher than that of chrysin suspension. Pharmacological studies suggested that the solid dispersion of chrysin was more powerful than chrysin raw material in improving biochemical indicators in the hyperlipidemic model in rats. This study reveals the potential use of a novel oral formulation of chrysin to reduce the currently required high dose.

Polysaccharide based transdermal patches for chronic wound healing: Recent advances and clinical perspective

Polysaccharides form a major class of natural polymers with diverse applications in biomedical science and tissue engineering. One of the key thrust areas for polysaccharide materials is skin tissue engineering and regeneration, whose market is estimated to reach around 31 billion USD globally by 2030, with a compounded annual growth rate of 10.46 %. Out of this, chronic wound healing and management is a major concern, especially for underdeveloped and developing nations, mainly due to poor access to medical interventions for such societies. Polysaccharide materials have shown promising results and clinical potential in recent decades with regard to chronic wound healing. Their low cost, ease of fabrication, biodegradability, and ability to form hydrogels make them ideal candidates for managing and healing such difficult-to-heal wounds. The present review presents a summary of the recently explored polysaccharide-based transdermal patches for managing and healing chronic wounds. Their efficacy and potency of healing both as active and passive wound dressings are evaluated in several in-vitro and in-vivo models. Finally, their clinical performances and future challenges are summarized to draw a road map towards their role in advanced wound care.

A bio-polymeric scaffold incorporated with p-Coumaric acid enhances diabetic wound healing by modulating MMP-9 and TGF-β3 expression

Diabetic wounds lead to severe health complications as the tissue regeneration process fails predominantly due to prolonged inflammation, reactive oxygen species generation, and imbalance in collagen turnover. Modern wound dressings that can aid in wound management thus improving the public healthcare system, is the present need. This study aims to fabricate an effective wound dressing using plant polyphenol to treat chronic wounds as polyphenols possess excellent wound-healing ability. The collagen scaffold enriched with the polyphenol, p-Coumaric acid, was fabricated by freeze-drying method (Col-OxP3-Ca) and examined for its wound-healing ability by in vitro and in vivo analyses. Col-OxP3-Ca scaffold exhibited 85% antioxidant activity, biocompatibility in fibroblast cells, enhanced cell proliferation and migration rate. The diabetic excision wound treated with Col-OxP3-Ca scaffold healed within 21 days and a well-developed epidermis, blood vessels, hair follicle formation, fewer inflammatory cells and collagen deposition was observed in histological analysis. The immunohistochemical results depicted the enhanced expression of TGF-β3 and lessened expression of the MMP-9 in Col-OxP3-Ca scaffold treatment group. p-Coumaric acid shortened the inflammatory stage, enhanced angiogenesis, tissue regeneration and balanced collagen turnover during healing. From this, we can accomplish that the Col-OxP3-Ca wound dressing could be an outstanding alternative to treat chronic wounds.

Natural Compounds and Biopolymers-Based Hydrogels Join Forces to Promote Wound Healing

Rapid and complete wound healing is a clinical emergency, mainly in pathological conditions such as Type 2 Diabetes mellitus. Many therapeutic tools are not resolutive, and the research for a more efficient remedial remains a challenge. Wound dressings play an essential role in diabetic wound healing. In particular, biocompatible hydrogels represent the most attractive wound dressings due to their ability to retain moisture as well as ability to act as a barrier against bacteria. In the last years, different functionalized hydrogels have been proposed as wound dressing materials, showing encouraging outcomes with great benefits in the healing of the diabetic wounds. Specifically, because of their excellent biocompatibility and biodegradability, natural bioactive compounds, as well as biomacromolecules such as polysaccharides and protein, are usually employed in the biomedical field. In this review, readers can find the main discoveries regarding the employment of naturally occurring compounds and biopolymers as wound healing promoters with antibacterial activity. The emerging approaches and engineered devices for effective wound care in diabetic patients are reported and deeply investigated.

LC-TOF-MS/MS and GC-MS based phytochemical profiling and evaluation of wound healing activity of Oroxylum Indicum (L.) Kurz (Beka)

Background: Beka (Oroxylum indicum (L.) Kurz) has been used as a culinary herb and natural remedy by the local communities in Malaysia. The leaf of O. indicum is traditionally used for the treatment of diarrhea, high blood pressure, and improving digestive health. Objectives: The present study was conducted to evaluate the phytochemical constituents and wound healing properties (in vitro and in vivo models) of aqueous and ethanol extracts of O. indicum leaves. Methods: The total phenolic (TPC) and total flavonoid (TFC) contents in the plant extracts were determined by the spectrophotometric methods. Further, the extract was characterized by Liquid Chromatography Time-of-Flight Mass Spectrometry (LC-TOF-MS/MS) and Gas Chromatography-Mass Spectrometry (GC-MS). The wound healing activity was assessed using the in vitro scratch wound-healing assay and in vivo excisional wound model. Results: The results show the ethanol leaves extract had the higher TPC (164 mg GAE/g) when compared with the aqueous leaves extract (30 mg gallic acid equivalents/g). The ethanol leaves extract was also found to have higher TFC (101 mg Catechin equivalents/g) than the aqueous leaves extract (76 mg Catechin equivalents/g). The ethanol leaves extract was then used for further chemical analysis. The LC-TOF-MS/MS analysis showed that the leaves extracts of O. indicum contains many important compounds such as Orientin, Chrysin, Pinoquercetin, Cupressuflavone, Puerarin xyloside, Forsythiaside and Paederoside. In GC-MS analysis, 19 compounds were identified in ethanolic leaves extract. The wound healing studies shows that O. indicum has promising wound healing activity by increasing the rate of wound contraction significantly (p < 0.05). Conclusion: In conclusion, the present study showed that O. indicum leaf contains important phytochemicals and the wound healing potential of the O. indicum extract may probably be as a result of the presence of various phytoconstituents.

Fabrication, Property and Application of Calcium Alginate Fiber: A Review

As a natural linear polysaccharide, alginate can be gelled into calcium alginate fiber and exploited for functional material applications. Owing to its high hygroscopicity, biocompatibility, nontoxicity and non-flammability, calcium alginate fiber has found a variety of potential applications. This article gives a comprehensive overview of research on calcium alginate fiber, starting from the fabrication technique of wet spinning and microfluidic spinning, followed by a detailed description of the moisture absorption ability, biocompatibility and intrinsic fire-resistant performance of calcium alginate fiber, and briefly introduces its corresponding applications in biomaterials, fire-retardant and other advanced materials that have been extensively studied over the past decade. This review assists in better design and preparation of the alginate bio-based fiber and puts forward new perspectives for further study on alginate fiber, which can benefit the future development of the booming eco-friendly marine biomass polysaccharide fiber.

Study of the inhibitory effects of chrysin and its nanoparticles on mitochondrial complex II subunit activities in normal mouse liver and human fibroblasts

BACKGROUND

Mitochondrial complex ΙΙ has a unique biological role owing to its participation in both the citric acid cycle and the electron transport chain. Our goal was to evaluate the succinate dehydrogenase and ubiquinone oxidoreductase activity of mitochondrial complex II in the presence of chrysin and chrysin-chitosan nanoparticles. Chrysin chitosan nanoparticles were synthesized and characterized using ultraviolet spectroscopy, Fourier transform-infrared spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, drug release, and zeta potential. The binding affinity of chrysin to complex II subunits was assessed by molecular docking. The IC50 values were measured in a suspension of mouse mitochondria, and the inhibitory effect of chrysin and chrysin chitosan nanoparticles on mitochondrial complex ΙΙ was determined.

RESULTS

The free energy of binding between chrysin and complex ΙΙ subunits A, B, C, and D was -4.9, -5, -8.2, and -8.4 kcal/mol, respectively. The characteristic peak of chrysin was confirmed at 348 nm. The chrysin chitosan nanoparticles contained characteristic bands of both chrysin and chitosan. The crystalline nature of chrysin chitosan nanoparticles was confirmed by X-ray powder diffraction measurements showing the characteristic Bragg peaks of (11.2°), (32.2°), (19.6°), (27.6°), and (31.96°). Transmission and scanning electron microscopy revealed their spherical shape and an average particle size of 49.7 ± 3.02 nm. Chrysin chitosan nanoparticles showed a burst release within the initial 2 h followed by a steady release at 8 h. Their zeta potential was positive, between +35.5 and +80 mV. The IC50 of chrysin, chitosan nanoparticles, chrysin chitosan nanoparticles, and 5-fluorouracil was 34.66, 184.1, 12.2, and 0.05 μg/mL, respectively, in adult mice liver and 129, 311, 156, and 8.07 μg/mL, respectively, in normal human fibroblasts. When comparing the inhibitory effects on complex ΙΙ activity, application of the IC50 of chrysin, chitosan nanoparticles, chrysin chitosan nanoparticles, and 5-fluorouracil resulted in 40.14%, 90.9%, 86.7%, and 89% decreases in SDH activity and 70.09%, 86.74%, 60.8%, and 80.23% decreases in ubiquinone oxidoreductase activity in normal adult mice, but 80.9%, 89.06%, and 90% significant decreases in SDH activity, and 90%, 85%, and 95% decreases in ubiquinone reductase after treatment with chrysin, chrysin chitosan nanoparticles, and 5-fluorouracil, in normal human fibroblasts, respectively.

CONCLUSIONS

Chrysin and CCNPs exhibit potent inhibitory effects on SDH activity ubiquinone oxidoreductase activity.

An acid-catalyzed polyol in situ crosslinked alginate ester/Antarctic krill protein composite fiber with improved strength and water resistance

A novel alginate ester/Antarctic krill protein composite fiber with high strength and water resistance that is non-toxic.

Preparation of Teucrium polium extract-loaded chitosan-sodium lauryl sulfate beads and chitosan-alginate films for wound dressing application

This study aimed to formulate sodium lauryl sulfate cross-linked chitosan beads and sodium alginate-chitosan films for designing a dressing that would shorten the healing time of skin wounds. Teucrium polium extract-loaded chitosan-sodium lauryl sulfate beads (CH-SLS) and chitosan-alginate (CH-ALG) films were prepared and characterized by using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM). The swelling properties of the CH-SLS beads were also analyzed in a water solution. The obtained Teucrium polium extract-loaded CH-SLS beads and CH-ALG films (TBF) were further incorporated into the commercial adhesive dressing. This TBF wound dressing was then investigated for evaluation of its wound healing potential in the mice using the excision wound model. Healing was assessed by the macroscopic appearance and the rate of wound contraction during 8 days. On day 4, the TBF-treated wounds exhibited 98% reduction in the wound area when they were compared with healing ointment, elastic adhesive dressing, and untreated wounds which were exhibited 63%, 43%, and 32%, respectively. Furthermore, the application of TBF dressing reduced skin wound rank scores and increased the percentage of wounds contraction. These results demonstrate that TBF dressing improves considerably the healing rate and the macroscopic wound appearance at a short delay and this application may have therapeutic benefits in wound healing.