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1.
Sci Rep ; 14(1): 5829, 2024 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461158

RESUMO

Plants represents a huge source of bioactive materials that have been used since the old times in the treatment of many diseases. Balanites aegyptiaca, known as desert date, has been used in treatment of fever, diabetes and bacterial infection. Desert dates contains a hard seed that resembles 50-60% of the fruit. The seed extract contains many fatty acids, amino acids and other bioactive materials that gives the extract its antioxidant and anti-inflammatory properties. The study aimed to use Balanites seed extract-loaded chitosan nanoparticles (SeEx-C NPs) for the treatment of streptozotocin (STZ)-induced diabetes in male Sprague Dawley rats. Animals were divided into two main divisions (healthy and diabetic rats). Each division contained seven groups (5 rats/group): control untreated group I, SeEx treated group II and group III (10 and 20 mg/kg b.w., respectively), C NPs treated group IV and group V (10 and 20 mg/kg b.w., respectively) and SeEx-C NPs treated group VI and group VII (10 and 20 mg/kg b.w., respectively). The therapeutical effects of SeEx-C NPs were evaluated through biochemical and immunological assessments in rats' pancreases. The results showed that SeEx-C NPs (10 and 20 mg/kg b.w.) reduced the oxidative stress and inflammation in rats' pancreases allowing the islets neogenesis. The loading of SeEx on C NPs allowed the delivery of fatty acids (oleic, lauric and myristic acid), amino acids (lysine, leucine, phenylalanine and valine) and minerals to pancreatic beta-cells in a sustainable manner. SeEx-C NPs administration successfully increased insulin secretion, allowed pancreatic islets neogenesis and reduced oxidative stress and inflammation.


Assuntos
Quitosana , Diabetes Mellitus Experimental , Hiperglicemia , Nanopartículas , Ratos , Animais , Insulina/metabolismo , Quitosana/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Ratos Sprague-Dawley , Estresse Oxidativo , Sementes/metabolismo , Inflamação/tratamento farmacológico , Nanopartículas/química
2.
Sci Rep ; 14(1): 3430, 2024 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341481

RESUMO

Chitosan is a natural biodegradable biopolymer that has drawbacks in mechanical and antibacterial properties, limiting its usage in biological and medicinal fields. Chitosan is combined with other naturally occurring substances possessing biological antibacterial qualities in order to broaden its application. Ethanolic apricot kernel seed extract was prepared, analyzed, and incorporated into chitosan film with different concentrations (0.25, 0.5, and 0.75 wt%). Furthermore, the effect of AKSE and γ-radiation (20 Gy and 20 kGy) on the physical properties of the film was studied. The prepared films were characterized by Fourier transform infrared spectroscopy (FTIR), which revealed that AKSE did not cause any change in the molecular structure, whereas the γ-irradiation dose caused a decrease in the peak intensity of all concentrations except 0.75 wt%, which was the most resistant. In addition, their dielectric, optical, and antimicrobial properties were studied. Also, AKSE-enhanced optical qualities, allowed them to fully block light transmission at wavelengths of 450-600 nm. The dielectric properties, i.e., permittivity (ε'), dielectric loss (ε''), and electrical conductivity (σ), increased with increasing AKSE concentration and film irradiation. The antimicrobial studies revealed that the antimicrobial activity against Escherichia coli and Canodida albicans increased with AKSE incorporation.


Assuntos
Anti-Infecciosos , Quitosana , Prunus armeniaca , Quitosana/farmacologia , Quitosana/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Embalagem de Alimentos/métodos , Extratos Vegetais/farmacologia , Extratos Vegetais/química
3.
J Chromatogr A ; 1719: 464712, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38377662

RESUMO

A drastic increase in demand for electric vehicles and energy storage systems increases lithium (Li) need as a critical metal for the 21st century. Lithium manganese oxides stand out among inorganic adsorbents because of their high capacity, chemical stability, selectivity, and affordability for lithium recovery from aqueous media. This study investigates using hydrometallurgically synthesized lithium manganese oxide (Li1.6Mn1.6O4) in granular form coated with cross-linked chitosan for lithium recovery from water. Characterization methods such as SEM, FTIR, XRD, and BET reveal the successful synthesis of the composite adsorbent. Granular cross-linked chitosan-coated and delithiated lithium manganese oxide (CTS/HMO) adsorbent demonstrated optimal removal efficiency of 86 % at pH 12 with 4 g/L of adsorbent dosage. The Langmuir isotherm at 25 °C, which showed monolayer adsorption with a maximum capacity of 4.94 mg/g, a better fit for the adsorption behavior of CTS/HMO. Adsorption was endothermic and thermodynamically spontaneous. Lithium adsorption followed the pseudo-first-order kinetic model.


Assuntos
Óxido de Alumínio , Quitosana , Óxido de Magnésio , Poluentes Químicos da Água , Água , Manganês , Lítio , Quitosana/química , Adsorção , Óxidos/química , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
4.
Int J Biol Macromol ; 261(Pt 2): 129900, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316329

RESUMO

The presence of potentially toxic elements and compounds poses threats to the quality and safety of fruit juices. Among these, Hg(II) is considered as one of the most poisonous heavy metals to human health. Traditional chitosan-based and selenide-based adsorbents face challenges such as poor adsorption capacity and inconvenient separation in juice applications. In this study, we prepared nano­selenium functionalized chitosan gel beads (nanoSe@CBs) and illustrated the synergistic promotions between chitosan and nanoSe in removing Hg(II) from apple juice. The preparation conditions, adsorption behaviors, and adsorption mechanism of nanoSe@CBs were systematically investigated. The results revealed that the adsorption process was primarily controlled by chemical adsorption. At the 0.1 % dosage, the adsorbent exhibited high uptake, and the maximum adsorption capacity from the Langmuir isotherm model could reach 376.5 mg/g at room temperature. The adsorbent maintained high adsorption efficiency (> 90 %) across a wide range of Hg(II) concentrations (0.01 to 10 mg/L) and was unaffected by organic acids present in apple juice. Additionally, nanoSe@CBs showed negligible effects on the quality of apple juice. Overall, nanoSe@CBs open up possibilities to be used as a safe, low-cost and highly-efficient adsorbent for the removal of Hg(II) from juices and other liquid foods.


Assuntos
Quitosana , Malus , Mercúrio , Selênio , Poluentes Químicos da Água , Humanos , Sucos de Frutas e Vegetais , Malus/química , Quitosana/química , Adsorção , Cinética , Concentração de Íons de Hidrogênio
5.
Molecules ; 29(3)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38338454

RESUMO

In the presented study, a variety of hybrid and single nanomaterials of various origins were tested as novel platforms for horseradish peroxidase immobilization. A thorough characterization was performed to establish the suitability of the support materials for immobilization, as well as the activity and stability retention of the biocatalysts, which were analyzed and discussed. The physicochemical characterization of the obtained systems proved successful enzyme deposition on all the presented materials. The immobilization of horseradish peroxidase on all the tested supports occurred with an efficiency above 70%. However, for multi-walled carbon nanotubes and hybrids made of chitosan, magnetic nanoparticles, and selenium ions, it reached up to 90%. For these materials, the immobilization yield exceeded 80%, resulting in high amounts of immobilized enzymes. The produced system showed the same optimal pH and temperature conditions as free enzymes; however, over a wider range of conditions, the immobilized enzymes showed activity of over 50%. Finally, a reusability study and storage stability tests showed that horseradish peroxidase immobilized on a hybrid made of chitosan, magnetic nanoparticles, and selenium ions retained around 80% of its initial activity after 10 repeated catalytic cycles and after 20 days of storage. Of all the tested materials, the most favorable for immobilization was the above-mentioned chitosan-based hybrid material. The selenium additive present in the discussed material gives it supplementary properties that increase the immobilization yield of the enzyme and improve enzyme stability. The obtained results confirm the applicability of these nanomaterials as useful platforms for enzyme immobilization in the contemplation of the structural stability of an enzyme and the high catalytic activity of fabricated biocatalysts.


Assuntos
Quitosana , Nanotubos de Carbono , Selênio , Enzimas Imobilizadas/química , Peroxidase do Rábano Silvestre/química , Quitosana/química , Estabilidade Enzimática , Íons , Concentração de Íons de Hidrogênio
6.
Int J Biol Macromol ; 263(Pt 2): 130391, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38417746

RESUMO

The textiles for medical use and the purification of textile factory effluents have become the most crucial part of the human healthcare sector. In this study bioactive compounds produced by four distinct plant extracts were used for the synthesis of zinc oxide nanoparticles. The four different ZnO nanoparticles were comprehensively characterized by different analytical techniques. XRD analysis revealed the crystalline nature and phase purity of the ZnO nanoparticles. FTIR spectra provided information on the function of plant extracts in the stabilization or capping process. The size distribution and morphological diversity of the nanoparticles were further clarified by SEM and TEM images. The photocatalytic degradation activity of the four ZnO nanoparticles on two different dyes showed that ZnO nanoparticles prepared from A. indica were most effective for the degradation of 98 % and 91 % of Rhodamine B and Alizarin red dye respectively. The selected ZnO nanoparticles from A. indica were used to prepare ZnO-chitosan nanocomposites before coating on cotton fabrics. The hydrophobicity, UV protection factor, and antibacterial activity of ZnO-chitosan nanocomposites, when coated on cotton fabrics, were also examined. The overall results demonstrated the ZnO and ZnO-chitosan nanocomposite prepared in the present study as a promising material for environmental remediation application.


Assuntos
Quitosana , Nanocompostos , Óxido de Zinco , Humanos , Óxido de Zinco/química , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química , Têxteis , Corantes , Nanocompostos/química , Extratos Vegetais/química
7.
Food Chem ; 443: 138506, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38306905

RESUMO

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


Assuntos
Quitosana , Petróleo , Álcool de Polivinil/química , Quitosana/química , Embalagem de Alimentos , Biopolímeros/química
8.
Carbohydr Polym ; 330: 121839, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368115

RESUMO

Cancer, a global health challenge of utmost severity, necessitates innovative approaches beyond conventional treatments (e.g., surgery, chemotherapy, and radiation therapy). Unfortunately, these approaches frequently fail to achieve comprehensive cancer control, characterized by inefficacy, non-specific drug distribution, and the emergence of adverse side effects. Nanoscale systems based on natural polymers like chitosan have garnered significant attention as promising platforms for cancer diagnosis and therapy owing to chitosan's inherent biocompatibility, biodegradability, nontoxicity, and ease of functionalization. Herein, recent advancements pertaining to the applications of chitosan nanoparticles in cancer imaging and drug/gene delivery are deliberated. The readers are introduced to conventional non-stimuli-responsive and stimuli-responsive chitosan-based nanoplatforms. External triggers like light, heat, and ultrasound and internal stimuli such as pH and redox gradients are highlighted. The utilization of chitosan nanomaterials as contrast agents or scaffolds for multimodal imaging techniques e.g., magnetic resonance, fluorescence, and nuclear imaging is represented. Key applications in targeted chemotherapy, combination therapy, photothermal therapy, and nucleic acid delivery using chitosan nanoformulations are explored for cancer treatment. The immunomodulatory effects of chitosan and its role in impacting the tumor microenvironment are analyzed. Finally, challenges, prospects, and future outlooks regarding the use of chitosan-based nanosystems are discussed.


Assuntos
Quitosana , Nanopartículas , Nanoestruturas , Neoplasias , Humanos , Quitosana/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Nanoestruturas/química , Nanopartículas/uso terapêutico , Nanopartículas/química , Microambiente Tumoral
9.
Int J Biol Macromol ; 261(Pt 2): 129442, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38232873

RESUMO

In this paper, the effects of extrusion, ultrasound on physicochemical properties of liposomes were studied, and the liposomes were prepared by ethanol injection combined with extrusion-ultrasound. In addition, the quality of PhGs lips, pectin-coated PhGs lips (P-lips) and chitosan-coated PhGs lips (C-lips) was evaluated by the average particle size, encapsulation efficiency (EE) and other indicators, which indicated that the nanoparticles had been successfully prepared. Compared with extrusion or ultrasonic operation alone, the EEs of ethanol injection combined with extrusion-ultrasonic increased by 8 % and 18 % respectively. Subsequently, transmission electron microscopy, Fourier transform infrared spectroscopy and DSC thermal analysis showed that PhGs in PhGs lips may produce hydrogen bonding forces with phospholipids, and pectin and chitosan in P-lips and C-lips were not only coated on the surface of PhGs lips, but also might have some interaction between them. Cell experiments showed that PhGs lips, P-lips and C-lips can effectively improve the bioavailability of PhGs. In addition, the storage stability of P-lips and C-lips was not significantly improved compared to PhGs lips, but their digestive stability was significantly improved, and the final retention rate in simulated intestinal fluid was about 25 % higher than that of PhGs lips.


Assuntos
Quitosana , Lipossomos , Lipossomos/química , Quitosana/química , Pectinas/química , Etanol , Digestão , Tamanho da Partícula
10.
J Mater Chem B ; 12(6): 1624-1635, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38270492

RESUMO

Colorectal cancer is one of the most common malignant tumors in the world, and its treatment strategies mainly include surgical resection, chemotherapy, adjuvant radiotherapy, and immunotherapy. Among them, chemotherapy inevitably produces systemic toxicity due to the lack of tumor targeting properties and drug resistance caused by long-term medication frequently occurs, immensely constraining the efficacy of chemotherapy alone. To solve the above-mentioned problems, rhamnolipid was used to encapsulate the chemotherapeutic drug 5-FU and photothermal agent bismuthene nanosheets (BiNS), chitosan was applied as the shell of the nanoparticle, and BiNS@RHL-CS/5-FU NPs for oral administration was successfully prepared. When transported in the stomach and small intestine, the double protection of rhamnolipid and chitosan shell prevented the early release of BiNS and 5-FU. When transported to the colon, ß-glycosidase existing in the microenvironment along with elevated pH degraded the chitosan shell, and the reduction in particle size was beneficial for tumor tissue to uptake nanoparticles, thus greatly improving the tumor targeting ability of 5-FU and reducing the systemic toxicity. Due to the presence of BiNS, 1.0 W cm-2 808 nm laser irradiation significantly increased the temperature of the tumor site, not only killing tumor cells directly but also promoting cell uptake and penetration of nanoparticles in the tumor tissue, accelerating the release of 5-FU and improving the sensitivity of tumor cells to chemotherapy, eventually solving the shortcomings of traditional chemotherapy alone. Excellent anti-tumor efficacy has been achieved in both in vitro and in vivo experiments.


Assuntos
Quitosana , Neoplasias Colorretais , Hipertermia Induzida , Nanopartículas , Humanos , Quitosana/química , Nanopartículas/química , Fluoruracila , Microambiente Tumoral
11.
Acta Biomater ; 176: 128-143, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38278340

RESUMO

Chronic diabetic wounds are a severe complication of diabetes, often leading to high treatment costs and high amputation rates. Numerous studies have revealed that nitric oxide (NO) therapy is a promising option because it favours wound revascularization. Here, base-paired injectable adhesive hydrogels (CAT) were prepared using adenine- and thymine-modified chitosan (CSA and CST). By further introducing S-nitrosoglutathione (GSNO) and binary l-arginine (bArg), we obtained a NO sustained-release hydrogel (CAT/bArg/GSON) that was more suitable for the treatment of chronic wounds. The results showed that the expression of HIF-1α and VEGF was upregulated in the CAT/bArg/GSON group, and improved blood vessel regeneration was observed, indicating an important role of NO. In addition, the research findings revealed that following treatment with the CAT/bArg/GSON hydrogel, the viability of Staphylococcus aureus and Escherichia coli decreased to 14 ± 2 % and 6 ± 1 %, respectively. Moreover, the wound microenvironment was improved, as evidenced by a 60 ± 1 % clearance of DPPH. In particular, histological examination and immunohistochemical staining results showed that wounds treated with CAT/bArg/GSNO exhibited denser neovascularization, faster epithelial tissue regeneration, and thicker collagen deposition. Overall, this study proposes an effective strategy to prepare injectable hydrogel dressings with dual NO donors. The functionality of CAT/bArg/GSON has been thoroughly demonstrated in research on chronic wound vascular regeneration, indicating that CAT/bArg/GSON could be a potential option for promoting chronic wound healing. STATEMENT OF SIGNIFICANCE: This article prepares a chitosan hydrogel utilizing the principle of complementary base pairing, which offers several advantages, including good adhesion, biocompatibility, and flow properties, making it a good material for wound dressings. Loaded GSNO and bArg can steadily release NO and l-arginine through the degradation of the gel. Then, the released l-arginine not only possesses antioxidant properties but can also continue to generate a small amount of NO under the action of NOS. This design achieves a sustained and stable supply of NO at the wound site, maximizing the angiogenesis-promoting and antibacterial effects of NO. More neovascularization and abundant collagen were observed in the regenerated tissues. This study provides an effective repair hydrogel material for diabetic wound.


Assuntos
Quitosana , Diabetes Mellitus , Humanos , Hidrogéis/farmacologia , Hidrogéis/química , Doadores de Óxido Nítrico/farmacologia , Adesivos/farmacologia , Quitosana/farmacologia , Quitosana/química , Angiogênese , Cicatrização , Colágeno/farmacologia , Antibacterianos/farmacologia , Arginina/farmacologia
12.
J Biomater Sci Polym Ed ; 35(5): 605-627, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38271010

RESUMO

Combination therapy using two or more drugs with different mechanisms of action is an effective strategy for treating cancer. This is because of the synergistic effect of complementary drugs that enhances their effectiveness. However, this approach has some limitations, such as non-specific distribution of the drugs in the tumor and the occurrence of dose-dependent toxicity to healthy tissues. To overcome these issues, we have developed a folate receptor-mediated co-delivery system that improves the access of chemotherapy drugs to the tumor site. We prepared a nanoplatform by encapsulating paclitaxel (PTX) and curcumin (CUR) in poly(caprolactone)-poly(ethylene glycol)-poly(caprolactone) (PCL-PEG-PCL) co-polymer using a double emulsion method and coating nanoparticles with pH-responsive chitosan-folic acid (CS-FA) conjugate. The nanocarrier's physicochemical properties were studied, confirming successful preparation with appropriate size and morphology. PTX and CUR could be released synchronously in a controlled and acid-facilitated manner. The dual drug-loaded nanocarrier exhibited excellent anti-tumor efficiency in MDA-MB-231 cells in vitro. The active targeting effect of FA concluded from the high inhibitory effect of dual drug-loaded nanocarrier on MDA-MB-231 cells, which have overexpressed folate receptors on their surface, compared to Human umbilical vein endothelial cells (HUVEC). Overall, the nanoengineered folate receptor-mediated co-delivery system provides great potential for safe and effective cancer therapy.


Assuntos
Neoplasias da Mama , Quitosana , Curcumina , Nanopartículas , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Quitosana/química , Células Endoteliais , Polímeros/química , Paclitaxel/química , Curcumina/farmacologia , Curcumina/uso terapêutico , Nanopartículas/química , Ácido Fólico/química , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Portadores de Fármacos/química
13.
J Biomater Sci Polym Ed ; 35(5): 628-656, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38284334

RESUMO

In this study, the pH-responsive API-CMCS-SA (ACS) polymeric nanoparticles (NPs) based on 1-(3-amino-propyl) imidazole (API), stearic acid (SA), and carboxymethyl chitosan (CMCS) were fabricated for the effective transport of curcumin (CUR) in liver cancer. CUR-ACS-NPs with various degrees of substitution (DS) were employed to prepare through ultrasonic dispersion method. The effect of different DS on NPs formation was discussed. The obtained CUR-ACS-NPs (DSSA=12.4%) had high encapsulation rate (more than 85%) and uniform particle size (186.2 ± 1.42 nm). The CUR-ACS-NPs showed better stability than the other groups. Drug release from the CUR-ACS-NPs was pH-dependent, and more than 90% or 65% of CUR was released in 48 h in weakly acid medium (pH 5.0 or 6.0, respectively). Additionally, the CUR-ACS-NPs increased the intracellular accumulation of CUR and demonstrated high anticancer effect on HepG2 cells compared with the other groups. CUR-ACS-NPs prolonged the retention time of the drug, and the area under the curve (AUC) increased significantly in vivo. The in vivo antitumor study further revealed that the CUR-ACS-NPs exhibited the capability of inhibiting tumor growth and lower systemic toxicity. Meanwhile, CUR, CUR-CS-NPs, and CUR-ACS-NPs could be detected in the evaluated organs, including tumor, liver, spleen, lung, heart, and kidney in distribution studies. Among them, CUR-ACS-NPs reached the maximum concentration at the tumor site, indicating the tumor-targeting properties. In short, the results suggested that CUR-ACS-NPs could act a prospective drug transport system for effective delivery of CUR in cancer treatment.


Assuntos
Quitosana , Curcumina , Neoplasias Hepáticas , Nanopartículas , Humanos , Curcumina/química , Quitosana/química , Portadores de Fármacos/química , Nanopartículas/química , Neoplasias Hepáticas/tratamento farmacológico , Concentração de Íons de Hidrogênio , Tamanho da Partícula
14.
Int J Biol Macromol ; 260(Pt 1): 129444, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38232881

RESUMO

Hydrogels prepared with natural and synthetic polymers were found to be applicable for the development of resistance against some Gram positive and negative bacterial species. Numerous studies have shown that chitosan polymers can be advantageous to be used in medicine due to their high antibacterial activity. In this study, biocompatible yellow cantorone oil doped hydrogels (chitosan/poly(vinyl alcohol) based) with antimicrobial properties were synthesized. The structural, morphological, swelling and mechanical properties of these biocompatible hydrogels prepared by double crosslinking were investigated and characterized. FTIR spectroscopy showed the appearance of new imine and acetal bonds due to both covalent cross-linking. In vitro cytotoxicity evaluation revealed that hydrogels showed weak cytotoxic effect. In the antimicrobial evaluation, it was determined that the hydrogel containing only chitosan showed better antimicrobial effect against Escherichia coli, Pseudomonas auriginosa, Staphylococcus aureus and Enterococcus faecalis bacteria than the one containing St. John's Wort oil. The antibacterial effect of polyvinyl alcohol/chitosan hydrogel was low. In our wound healing study, chitosan hydrogel loaded with yellow St. John's Wort oil was more effective in reducing wound size.


Assuntos
Anti-Infecciosos , Quitosana , Hypericum , Álcool de Polivinil , Quitosana/farmacologia , Quitosana/química , Hidrogéis/química , Hypericum/química , Antibacterianos/química , Polímeros
15.
Int J Biol Macromol ; 260(Pt 1): 129450, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38232896

RESUMO

In this study, we fabricated a novel biodegradable functional film using natural polysaccharides by adding jujube seed powder as an active ingredient. Scanning electron microscopy analysis showed agglomerate formation in the film with increasing concentration of seed powder. Fourier transform-infrared spectroscopy study demonstrated an electrostatic interaction between pectin and chitosan. The water solubility and swelling degree significantly decreased from 55.5 to 47.7 % and 66.0 to 41.9 %, respectively, depicting the film's water resistance properties. Higher opacity and lower transmittance value of the film indicated its protective effect towards light-induced oxidation of food. It was observed that the fabricated active film biodegraded to 82.33 % in 6 days. The DPPH radical scavenging activity of 98.02 % was observed for the functional film. The film showed antifungal activity against B. cinerea and P. chrysogenum. The highest zone of inhibition was obtained against food spoiling bacteria B. subtilis followed by S. aureus, P. aeruginosa and E. coli. Genotoxicity studies with the fabricated film showed a mitotic index of 8 % compared to 3 % in the control film. We used the fabricated film to preserve grapefruits, and the result showed that it could preserve grapes for ten days with an increase in antioxidant activity and polyphenolic content.


Assuntos
Quitosana , Frutas , Extratos Vegetais , Ziziphus , Pós/farmacologia , Embalagem de Alimentos , Staphylococcus aureus , Escherichia coli , Quitosana/química , Polissacarídeos/farmacologia , Água/farmacologia , Pectinas/farmacologia
16.
Int J Biol Macromol ; 260(Pt 2): 129275, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38242408

RESUMO

Adsorption-based treatment of sulfate contaminated water sources present challenges due to its favourable hydration characteristics. Herein, a copper-modified granular chitosan-based biocomposite (CHP-Cu) was prepared and characterized for its sulfate adsorption properties at neutral pH via batch equilibrium and fixed-bed column studies. The CHP-Cu adsorbent was characterized by complementary methods: spectroscopy (IR, Raman, X-ray photoelectron), thermal gravimetry analysis (TGA) and pH-based surface charge analysis. Sulfate adsorption at pH 7.2 with CHP-Cu follows the Sips isotherm model with a maximum adsorption capacity (407 mg/g) that exceeds most reported values of granular biosorbents at similar conditions. For the dynamic adsorption study, initial sulfate concentration, bed height, and flow rate were influential parameters governing sulfate adsorption. The Thomas and Yoon-Nelson models yield a sulfate adsorption capacity (146 mg/g) for the fixed bed system at optimized conditions. CHP-Cu was regenerated over 5 cycles (33 % to 31 %) with negligible Cu-leaching. The adsorbent also displays excellent sulfate uptake properties, regenerability, and sustainable adsorbent properties for effective point-of-use sulfate remediation in aqueous media near neutral pH (7.2). This sulfate remediation strategy is proposed for other oxyanion systems relevant to contaminated environmental surface and groundwater resources.


Assuntos
Quitosana , Poluentes Químicos da Água , Purificação da Água , Quitosana/química , Cobre/química , Sulfatos , Poluentes Químicos da Água/química , Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética
17.
Int J Biol Macromol ; 260(Pt 2): 129615, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246437

RESUMO

To preserve the viability of probiotics during digestion and storage, encapsulation techniques are necessary to withstand the challenges posed by adverse environments. A core-shell structure has been developed to provide protection for probiotics. By utilizing sodium alginate (SA) / Lycium barbarum polysaccharide (LBP) as the core material and chitosan (CS) as the shell, the probiotic load reached 9.676 log CFU/mL. This formulation not only facilitated continuous release in the gastrointestinal tract but also enhanced thermal stability and storage stability. The results obtained from Fourier transform infrared spectroscopy and thermogravimetric analysis confirmed that the addition of LBP and CS affected the microstructure of the gel by enhancing the hydrogen bond force, so as to achieve controlled release. Following the digestion of the gel within the gastrointestinal tract, the released amount was determined to be 9.657 log CFU/mL. The moisture content and storage stability tests confirmed that the encapsulated Lactiplantibacillus plantarum maintained good activity for an extended period at 4 °C, with an encapsulated count of 8.469 log CFU/mL on the 28th day. In conclusion, the newly developed core-shell gel in this study exhibits excellent probiotic protection and delivery capabilities.


Assuntos
Quitosana , Medicamentos de Ervas Chinesas , Probióticos , Alginatos/química , Quitosana/química , Viabilidade Microbiana , Géis , Probióticos/química
18.
Carbohydr Polym ; 328: 121738, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38220330

RESUMO

Developing artificial substitutes that mimic the structures and performances of natural cartilage is of great importance. However, it is challenging to integrate the high strength, excellent biocompatibility, low coefficient of friction, long-term wear resistance, outstanding swelling resistance, and osseointegration potential into one material. Herein, a sandwich hydrogel with cartilage-mimetic structures and performances was prepared to achieve this goal. The precursor hydrogel was obtained by freezing-thawing the mixture of poly vinyl alcohol, chitosan and deionized water three cycles, accompanied by soaking in sodium hyaluronate solution. The top of the precursor hydrogel was hydrophobically modified with lauroyl chloride and then loaded with lecithin, while the bottom was mineralized with hydroxyapatite. Due to the multiple linkages (crystalline domains, hydrogen bonds, and ionic interactions), the compressive stress was 71 MPa. Owing to the synergy of the hydrophobic modification and lecithin, the coefficient of friction was 0.01. Additionally, no wear trace was observed after 50,000 wear cycles. Remarkably, hydroxyapatite enabled the hydrogel osseointegration potential. The swelling ratio of the hydrogel was 0.06 g/g after soaking in simulated synovial fluid for 7 days. Since raw materials were non-toxic, the cell viability was 100 %. All of the above merits make it an ideal material for cartilage replacement.


Assuntos
Quitosana , Quitosana/química , Hidrogéis/farmacologia , Hidrogéis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Álcool de Polivinil/química , Ácido Hialurônico , Teste de Materiais , Lecitinas , Durapatita/química , Cartilagem
19.
Chem Biodivers ; 21(1): e202300187, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38164058

RESUMO

In this study, we developed Solid Lipid Nanoparticles (SLN-NPs) loaded with Artemisia vulgaris essential oil and coated with folic acid-chitosan (AVEO-SCF-NPs) to enhance drug delivery in biotechnology and pharmaceutical sectors. AVEO-SCF-NPs were synthesized using homogenization and ultra-sonication methods and comprehensively characterized. These nanoparticles exhibited a particle size of 253.67 nm, Polydispersity Index (PDI) of 0.26, zeta potential (ζ-p) of +39.96 mV, encapsulation efficiency (%EE) of 99.0 %, and folic acid binding efficiency (% FB) of 46.25 %. They effectively inhibited MCF-7, HT-29, and PC-3 cancer cells with IC50 values of 48.87 µg/mL, 88.48 µg/mL, and 121.34 µg/mL, respectively, and demonstrated antibacterial properties against Gram-positive strains. AVEO-SCF-NPs also exhibited scavenging effects on ABTS (IC50 : 203.83 µg/mL) and DPPH (IC50: 680.86 µg/mL) free radicals and inhibited angiogenesis, as confirmed through CAM and qPCR assays. Furthermore, these nanoparticles induced apoptosis, evidenced by up-regulation of caspase 3 and 9, down-regulation of TNF-α genes, and an increase in SubG1 phase cells. The high loading capacity of SCF-NPs for AVEO, coupled with their multifaceted biological properties, highlights AVEO-SCF-NPs as promising candidates for cancer therapy in the biotechnology and pharmaceutical industries.


Assuntos
Artemisia , Quitosana , Lipossomos , Nanopartículas , Humanos , Quitosana/farmacologia , Quitosana/química , Ácido Fólico/química , Nanopartículas/química
20.
Int J Biol Macromol ; 254(Pt 1): 127758, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38287596

RESUMO

This study has explored the potential of plant-derived oil bodies (OBs)-based oleogels as novel drug delivery systems for in vitro release under simulated physiological conditions. To obtain stable OBs-based oleogels, gum arabic (GA) and chitosan (CH) were coated onto the curcumin-loaded OBs using an electrostatic deposition technique, followed by 2,3,4-trihydroxybenzaldehyde (TB) induced Schiff-base cross-linking. Microstructural analyses indicated successful encapsulation of curcumin into the hydrophobic domain of the OBs through a pH-driven method combined with ultrasound treatment. The curcumin encapsulation efficiency of OBs increased up to 83.65 % and 92.18 % when GA and GA-CH coatings were applied, respectively, compared to uncoated OBs (63.47 %). In addition, GA-CH coatings retained the structural integrity of oleogel droplets with superior oil-holding capacity (99.07 %), while TB addition induced interconnected 3D-network structures with excellent gel strength (≥4.8 × 105 Pa) and thermal stability (≥80 °C). GA-CH coated oleogels appeared to provide the best protection for loaded bioactive against UV irradiation and high temperature-induced degradation during long-term storage. The combination of biopolymer coatings and TB-induced Schiff-base cross-linking synergistically hindered the simulated gastric degradability of oleogels, releasing only 23.35 %, 12.46 % and 7.19 % of curcumin by GA, GA-CH and GA-CH-TB stabilized oleogels, respectively, while also resulting in sustained release effects during intestinal conditions.


Assuntos
Quitosana , Curcumina , Goma Arábica/química , Curcumina/química , Quitosana/química , Preparações de Ação Retardada , Gotículas Lipídicas , Óleos de Plantas , Compostos Orgânicos
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