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1.
J Environ Manage ; 345: 118568, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37421718

RESUMO

Phosphate fertilizers have been excessively applied in agricultural production, bringing the risk of phosphorus (P) loss to nearby river systems and low utilization efficiency. In this study, eggshell-modified biochars prepared by pyrolysis of eggshell and corn straw or pomelo peel were applied to soil for enhancing P immobilization and utilization. The structure and properties of modified biochars before and after P adsorption were analyzed using the Brunauer-Emmett-Teller (BET) nitrogen adsorption method, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM). The eggshell-modified biochar performed an excellent adsorption performance for P (up to 200 mg/g), which was well described by the Langmuir model (R2 > 0.969), showing monolayer chemical adsorption with homogenous surface. The Ca(OH)2 appeared on the surface of eggshell modified biochars and changed to Ca5(PO4)3(OH) and CaHPO4(H2O)2 after P adsorption. The release of immobilized P by modified biochar increased with decreased pH. In addition, pot experiments of soybean indicated that the combined application of modified biochar and P fertilizer significantly increased the content of microbial biomass P in soil, raising from 4.18 mg/kg (control group) to 51.6-61.8 mg/kg (treatment group), and plants height increased by 13.8-26.7%. Column leaching experiments showed that P concentration in the leachate decreased by 97.9% with the modified biochar application. This research provides a new perspective that the eggshell-modified biochar could serve as a potential soil amendment for enhancing P immobilization and utilization.


Assuntos
Casca de Ovo , Solo , Animais , Biomassa , Fosfatos , Carvão Vegetal/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética
2.
Molecules ; 24(14)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315269

RESUMO

Mussel adhesive proteins (MAPs) have a unique ability to firmly adhere to different surfaces in aqueous environments via the special amino acid, 3,4-dihydroxyphenylalanine (DOPA). The catechol groups in DOPA are a key group for adhesive proteins, which is highly informative for the biomedical domain. By simulating MAPs, medical products can be developed for tissue adhesion, drug delivery, and wound healing. Hydrogel is a common formulation that is highly adaptable to numerous medical applications. Based on a discussion of the adhesion mechanism of MAPs, this paper reviews the formation and adhesion mechanism of catechol-functionalized hydrogels, types of hydrogels and main factors affecting adhesion, and medical applications of hydrogels, and future the development of catechol-functionalized hydrogels.


Assuntos
Bivalves/química , Catecóis/química , Animais , Bivalves/metabolismo , Di-Hidroxifenilalanina/química , Sistemas de Liberação de Medicamentos , Hidrogéis , Proteínas/metabolismo , Aderências Teciduais , Cicatrização
3.
Phys Chem Chem Phys ; 20(20): 14155-14165, 2018 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-29749422

RESUMO

Microwave absorbing materials with high absorption over a broad bandwidth when they have a small thickness are strongly desired due to their widespread applications. Herein, cerium oxide immobilized reduced graphene oxide (CeO2-rGO) hybrids with excellent microwave absorbing performance have been fabricated by a versatile one-step hydrothermal approach. Modern measurement techniques, including X-ray diffraction, Raman spectroscopy, electronic microscopy, X-ray photoelectron spectroscopy and vector network analysis, have been conducted to characterize the chemical composition, microstructure and electromagnetic performance of the as-obtained hybrids. Morphological analysis reveals that the CeO2 nanocrystals are homogeneously immobilized onto the rGO surface without any significant agglomeration. Interestingly, significant enhancement in the microwave absorbing performance has been observed for all the CeO2-rGO hybrids. For example, a CeO2-rGO hybrid with a 10 : 1 mass ratio of CeO2 to GO exhibits a minimum reflection loss (RL) of -45.94 dB, which is 73.35 times and 6.14 times that of the lone CeO2 and rGO, respectively. Moreover, the CeO2-rGO hybrid shows a broadband absorption feature with an effective absorption bandwidth (RL < -10 dB) of 4.5 GHz, and can be exploited for practical application in a frequency range of 3.68-18.00 GHz via tuning of the thickness. Investigation of the structure-property correlation indicates that such enhancements are attributed to conductive loss, polarization loss and multiple reflections which are mainly derived from the unique CeO2-rGO based architecture. In addition, the higher oxygen vacancy concentration of CeO2 in hybrids can promote electron transfer between CeO2 and rGO, leading to microwave attenuation enhancement. It is expected that these CeO2-rGO hybrids can be used as new microwave absorbers.

4.
Mar Drugs ; 16(8)2018 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-30081571

RESUMO

Effective hemostasis is vital to reduce the pain and mortality of patients, and the research and development of hemostatic materials are prerequisite for effective hemostasis. Chitosan (CS), with good biodegradability, biocompatibility and non-toxicity, has been widely applied in bio-medicine, the chemical industry, the food industry and cosmetics. The excellent hemostatic properties of CS have been extensively studied. As a result, chitosan-based composite hemostatic materials have been emerging. In this review, the hemostatic mechanism of chitosan is briefly discussed, and then the progress of research on chitosan-based composite hemostatic materials with multiple forms such as films, sponges, hydrogels, particles and fibers are introduced. Finally, future perspectives of chitosan-based composite hemostatic materials are given. The objective of this review is to provide a reference for further research and development of effective hemostatic materials.


Assuntos
Materiais Biocompatíveis/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Quitosana/farmacologia , Hemorragia/terapia , Hemostáticos/farmacologia , Animais , Organismos Aquáticos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Células Sanguíneas/efeitos dos fármacos , Quitosana/química , Quitosana/uso terapêutico , Técnicas Hemostáticas , Hemostáticos/química , Hemostáticos/uso terapêutico , Humanos
5.
Mar Drugs ; 16(12)2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30501087

RESUMO

A polyampholytic superabsorbent polymer (PASAP), sodium alginate-g-(polyacrylic acid-co-allyltrimethylammonium chloride) (SA-g-(PAA-co-PTM)), was prepared by free-radical graft copolymerization and characterized. The polymer exhibited pH-dependent swelling behaviors with extremely high swelling ratios, and was saline tolerant. The dye adsorption properties of SA-g-(PAA-co-PTM) were investigated using methylene blue (MB) as a cationic dye model. It was found that its dye adsorption capacity was significantly affected by the TM content in PASAP and pH of dye solution. The dye adsorption kinetics and isotherm obey the pseudo-second-order kinetic model and the Langmuir isotherm model, respectively, and the adsorption process is chemisorption in nature. In addition, SA-g-(PAA-co-PTM) exhibited high MB adsorption capacities in a wide pH range and reusability in at least five adsorption-desorption cycles, indicating its great application potentials as the adsorbent for dye removals from effluents.


Assuntos
Acrilatos/química , Resinas Acrílicas/química , Alginatos/química , Compostos de Amônio/química , Polímeros/química , Purificação da Água/métodos , Adsorção , Soluções Tampão , Corantes/química , Corantes/toxicidade , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno/química , Azul de Metileno/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
6.
J Microencapsul ; 32(1): 40-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25198909

RESUMO

Folate-chitosan nanoparticles, co-loaded with 5-fluourouacil (5-FU) and leucovorin (LV) and prepared by ionic gelation technology were physically microencapsulated by enteric polymer using a solvent evaporation method. Average particle size of the microencapsulated particles was in the range of 15 to 35 µm. High drug encapsulation efficiency was obtained for both 5-FU and LV in the microencapsulated particles. Both drugs were in amorphous state in the microencapsulated particles. By enteric coating, excellent pH-dependent release profile was achieved and no drug release was observed in simulated gastric and intestinal fluids. However, when the pH value reached the soluble threshold of Eudragit S-100, a constant and slow drug release was observed. The results indicated that these microencapsulated particles are a promising vehicle for selectively targeting drugs to colon in the chemotherapy of colon cancer.


Assuntos
Quitosana , Colo , Neoplasias do Colo/tratamento farmacológico , Portadores de Fármacos , Ácido Fólico , Nanopartículas/química , Cápsulas , Quitosana/química , Quitosana/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Ácido Fólico/química , Ácido Fólico/farmacologia , Humanos , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacologia
7.
Int J Biol Macromol ; 258(Pt 1): 128933, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38143071

RESUMO

In this study, zein-gallic acid covalent complex prepared by alkali treatment was utilized as an emulsifier to stabilize cinnamon essential oil (CEO) Pickering emulsion, and the chitosan-based (CZGE) films loaded with CEO Pickering emulsion were prepared by blending. The influences of different contents of CEO Pickering emulsion on the physical properties and biological activities of CZGE films were investigated. The results showed that Pickering emulsion had good compatibility with chitosan matrix and enhanced the interaction between film-forming matrix polymer. In addition, incorporating with CEO Pickering emulsion (15 %, v/v) significantly improved the mechanical and barrier properties of the films, and also enhanced the light transmittance and thermal stability of the films. Furthermore, the loading of emulsion also improved the antioxidant activities of the films and led to the formation of high antimicrobial property against food pathogens, and the slow-release behavior of CEO could effectively extend the biological activity of the films. These results suggested that Pickering emulsion has potential as a loading system and a plasticizer in active packaging, and the feasibility of CZGE film in food packaging.


Assuntos
Quitosana , Nanopartículas , Óleos Voláteis , Zeína , Cinnamomum zeylanicum , Ácido Gálico , Emulsões , Antibacterianos
8.
AAPS PharmSciTech ; 14(2): 585-92, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23463262

RESUMO

Shortage of functional groups on surface of poly(lactide-co-glycolide) (PLGA)-based drug delivery carriers always hampers its wide applications such as passive targeting and conjugation with targeting molecules. In this research, PLGA nanoparticles were modified with chitosan through physical adsorption and chemical binding methods. The surface charges were regulated by altering pH value in chitosan solutions. After the introduction of chitosan, zeta potential of the PLGA nanoparticle surface changed from negative charge to positive one, making the drug carriers more affinity to cancer cells. Functional groups were compared between PLGA nanoparticles and chitosan-modified PLGA nanoparticles. Amine groups were exhibited on PLGA nanoparticle surface after the chitosan modification as confirmed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The modified nanoparticles showed an initial burst release followed by a moderate and sustained release profile. Higher percentage of drugs from cumulative release can be achieved in the same prolonged time range. Therefore, PLGA nanoparticles modified by chitosan showed versatility of surface and a possible improvement in the efficacy of current PLGA-based drug delivery system.


Assuntos
Antimetabólitos Antineoplásicos/química , Quitosana/química , Portadores de Fármacos , Fluoruracila/química , Ácido Láctico/química , Nanopartículas , Ácido Poliglicólico/química , Química Farmacêutica , Quitosana/análogos & derivados , Preparações de Ação Retardada , Concentração de Íons de Hidrogênio , Cinética , Nanotecnologia , Espectroscopia Fotoeletrônica , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Tecnologia Farmacêutica/métodos
9.
Int J Biol Macromol ; 236: 123994, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36914059

RESUMO

The porous structure and hydrophilicity of coating shells affect the nutrient controlled-release performance of castor oil-based (CO) coated fertilizers. In order to solve these problems, in this study, the castor oil-based polyurethane (PCU) coating material was modified with liquefied starch polyol (LS) and siloxane, and a new coating material with cross-linked network structure and hydrophobic surface was synthesized, and used it to prepare the coated controlled-release urea (SSPCU). The results demonstrated that the cross-linked network formed by LS and CO improved the density and reduced the pores on the surface of the coating shells. The siloxane was grafted on the surface of coating shells to improve its hydrophobicity and thus delayed water entry. The nitrogen release experiment indicated that the synergistic effects of LS and siloxane improved the nitrogen controlled-release performance of bio-based coated fertilizers. Nutrient released longevity of SSPCU with 7 % coating percentage reached >63 days. Moreover, the nutrient release mechanism of coated fertilizer was further revealed by the analysis of the release kinetics analysis. Therefore, the results of this study provide a new idea and technical support for development of efficient and environment-friendly bio-based coated controlled-release fertilizers.


Assuntos
Fertilizantes , Siloxanas , Preparações de Ação Retardada/química , Óleo de Rícino , Nitrogênio/química
10.
Int J Biol Macromol ; 235: 123914, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36870659

RESUMO

In this study, amphiphilic chitosan (NPCS-CA) was synthesized by grafting quaternary phosphonium salt and cholic acid onto the chain of chitosan, aiming to develop an active edible film based on NPCS-CA and polyvinyl alcohol (PVA) incorporated with cinnamon essential oil (CEO) by the casting method. The chemical structure of the chitosan derivative was characterized by FT-IR, 1H NMR and XRD. Through the characterization of FT-IR, TGA, mechanical and barrier properties of the composite films, the optimal proportion of NPCS-CA/PVA was determined as 5/5. And, the tensile strength and elongation at break of the NPCS-CA/PVA (5/5) film with 0.4 % CEO were 20.32 MPa and 65.73 %, respectively. The results revealed that the NPCS-CA/PVA-CEO composite films exhibited an excellent ultraviolet barrier property at 200-300 nm and significantly reduced oxygen permeability, carbon dioxide permeability and water vapor permeability. Furthermore, the antibacterial property of film-forming solutions against E. coli, S. aureus, and C. lagenarium was distinctly improved with the increase of NPCS-CA/PVA proportion. And, the multifunctional films effectively extended the shelf-life of mangoes at 25 °C based on the characterization of surface changes and quality indexes. The NPCS-CA/PVA-CEO films could be developed as biocomposite food packaging material.


Assuntos
Quitosana , Óleos Voláteis , Óleos Voláteis/química , Quitosana/química , Álcool de Polivinil/química , Cinnamomum zeylanicum/química , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química , Embalagem de Alimentos/métodos
11.
Int J Biol Macromol ; 224: 1361-1372, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306905

RESUMO

Quercetin (QCT) has antioxidant, anti-inflammatory, anti-tumor and other important pharmacological activities, but the poor water solubility limits its application. In this work, the amphiphilic dextran (ADEX) was prepared by grafting L-cysteine and octadecylamine onto carboxymethyl dextran with the grafting rate of 21.29 % and 19.35 %. Then, the QCT-loaded nanomicelles (QNMs) were prepared by using ADEX as wall material and the QCT as core material via ultrasonic self-assembly method. The particle size and zeta potential of QNMs were 372 nm and 31.4 mV. Under simulated gastric and simulated intestinal fluids, the cumulative release QNMs were 37.54 % and 52.13 % within 180 min, and the QNMs showed better stability in simulated gastric fluid. The QNMs showed significantly better PTIO, OH and O2- scavenging activities than QCT. In addition, QNMs could effectively down-regulate the expression of pro-inflammatory cytokines and promoted the expression of anti-inflammatory cytokine. The cellular uptake results proved that the QNMs were more easily absorbed by cells than free QCT, indicating that the nano-encapsulation procedure effectively improved the uptake efficiency of QCT by cells.


Assuntos
Antioxidantes , Nanopartículas , Quercetina/farmacologia , Portadores de Fármacos , Micelas , Dextranos
12.
Carbohydr Polym ; 300: 120290, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36372497

RESUMO

In this paper, amphiphilic chitosan and carboxymethyl modified gellan gum were synthesized to develop an active edible fresh-keeping material. The optimal weight ratio of CMCS-g-CA/CMGG was determined as 5:2 through the characterization of Fourier transform infrared (FT-IR), Thermogravimetric analysis (TGA), mechanical and barrier properties of the composite films. In addition, the water vapor permeability and oxygen permeability of CMCS-g-CA/CMGG composite films incorporated with mustard essential oil were all declined, and the antibacterial property of the composite film solutions against E. coli, S. aureus and Bacillus anthracis was distinctly improved with the increase of mustard essential oil (MEO) dosage. Furthermore, the CMCS-g-CA/CMGG + 2.0 µL/mL MEO composite film exhibited an effective preservation on mango fruits during 20 days of storage based on the characterization of surface appearance and quality indexes of fruits. Hence, the multifunctional CMCA-g-CA/CMGG/MEO composite films can be served as a prospective eco-friendly packaging material for fruit preservation.


Assuntos
Quitosana , Mangifera , Óleos Voláteis , Óleos Voláteis/farmacologia , Staphylococcus aureus , Escherichia coli , Espectroscopia de Infravermelho com Transformada de Fourier , Mostardeira , Estudos Prospectivos , Antibacterianos/farmacologia , Permeabilidade , Embalagem de Alimentos
13.
Int J Biol Macromol ; 209(Pt A): 344-355, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35413309

RESUMO

As a natural antibacterial agent with pleasant fragrance, citral possesses low aqueous solubility. To improve citral loading in hydrophilic nanofiber, Pickering emulsion electrospinning strategy was proposed for anti-infection dressing development. The in-situ aggerated ß-cyclodextrin-citral inclusion complex particles (ßCPs) were used as emulsion stabilizers, while citral and carboxymethyl chitosan (CMCS)/polyvinyl alcohol (PVA) mixed solutions were used as the inner "dispersed oil phase" and outer "continuous water phase", respectively. The results of electronic microscope investigation shown ßCPs possessed regular cube appearances with a size of 5.5 ± 2.2 µm, which might improve the emulsion storage stability based on visual investigation. Moreover, randomly oriented and bead-on-string nanofibers with ßCPs uniformly distributed could be obtained under optimized compositions and electrospinning parameters. Despite volatilization during electrospinning, nanofibers with high citral loading possessed good antibacterial performance against Staphylococcus aureus and Escherichia coli. In vitro hemolysis test indicated that nanofibers were hemocompatible. In addition, both fiber matrix and citral could promote the proliferation of mouse fibroblast cells. And the permeability of the fibers was adjustable. Thus, CMCS/PVA/ßCPs/citral nanofibers could potentially protect wound from infection. In summary, CMCS/PVA/ßCPs/citral nanofibers seemed to be promising alternatives to conventional wound dressings.


Assuntos
Quitosana , Nanofibras , Monoterpenos Acíclicos , Animais , Antibacterianos/farmacologia , Bandagens , Emulsões , Escherichia coli , Camundongos , Álcool de Polivinil , Cicatrização
14.
Int J Biol Macromol ; 212: 11-19, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35598563

RESUMO

In this paper, a cationic photoinitiator (TAS) was used as a catalyst for the ring opening reaction of carboxymethyl chitosan (CMCS) and epoxidized soybean oil (ESO) under UV light to prepare CMCS-g-ESO conjugate, and the structure of the product was characterized by FT-IR, 1H NMR and GPC. Then, the spinosad-loaded microcapsules (SSD@CMCS-g-ESO) were prepared by ultrasonic self-assembly method. The results showed that TAS could catalyze the ring opening reaction of CMCS and ESO under UV-irradiation and the optimum reaction time was 1 h, with the molecular weight of 15,745. The average particle size of SSD@CMCS-g-ESO was about 2.16 µm, and the encapsulation efficiency (EE) and drug loading content (LC) of SSD@CMCS-g-ESO were 85.39 ± 2.05% and 20.17 ± 1.84%, respectively. In vitro release revealed that SSD@CMCS-g-ESO exhibited sustained-release and pH-responsive property, and the accumulative release in the buffer solution of pH = 6.5 and 7.4 was higher than in pH = 9.0. Furthermore, SSD@CMCS-g-ESO had a good antifungal properties against Fusarium oxysporum f. sp. cubense (Foc) compared with the unencapsulated SSD at the same drug dose. This work indicated that photo-chemical reactions could be used to prepare bio-based carrier materials to construct drugs delivery system for targeted treatment of fusarium wilt.


Assuntos
Quitosana , Fusarium , Quitosana/química , Portadores de Fármacos/química , Óleo de Soja , Espectroscopia de Infravermelho com Transformada de Fourier , Raios Ultravioleta
15.
Foods ; 11(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35741931

RESUMO

Honey peach (Prunus persica L.) is highly nutritious; it is an excellent source of sugars, proteins, amino acids, vitamins, and mineral elements. However, it is a perishable climacteric fruit that is difficult to preserve. In this study, "Feicheng" honey peach fruit was used as a test material to investigate the synergistic preservation effect of 1-methylcyclopropene (1-MCP) and laser microporous film (LMF). The peach fruits were fumigated for 24 h with 2 µL L-1 1-MCP, then packed in LMF. In comparison with the control treatment, 1-MCP + LMF treatment markedly decreased the respiration rate, weight loss, and rot rate of peach fruits. Moreover, the combination of 1-MCP and LMF suppressed the increase in soluble solids (SS) and reducing sugars (RS), as well as the decrease in titratable acid (TA) and ascorbic acid (AsA). The combined application also maintained a high protopectin content and low soluble pectin content; it reduced the accumulation of superoxide anions (O2-) and hydrogen peroxide (H2O2). Except in a few samples, the catalase (CAT) and ascorbate peroxidase (APX) activities were higher when treated by 1-MCP + LMF. Conversely, the phenylalanine deaminase (PAL), peroxidase (POD), lipase, lipoxygenase (LOX), polygalacturonase (PG), ß-glucosidase, and cellulase (Cx) activities were lower than in the control. Furthermore, 1-MCP + LMF treatment reduced the relative abundances of dominant pathogenic fungi (e.g., Streptomyces, Stachybotrys, and Issa sp.). The combined treatment improved the relative abundances of antagonistic fungi (e.g., Aureobasidium and Holtermanniella). The results indicated that the co-application of 1-MCP and LMF markedly reduced weight loss and spoilage, delayed the decline of nutritional quality, and inhibited the physiological and biochemical metabolic activities of peach during storage. These changes extended its shelf-life to 28 days at 5 °C. The results provide a reference for the commercial application of this technology.

16.
Int J Biol Macromol ; 222(Pt B): 3100-3107, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36244532

RESUMO

Chitosan (CS) is a natural marine polysaccharide with good biocompatibility and biodegradability. But its poor water solubility and antibacterial activity limit its application in fruits preservation. In this study, based on the advantage of quaternary phosphonium salt (QP) and salicylic acid (SA) with good antibacterial activities and different antibacterial mechanisms, a novel antibacterial coating material was synthesized by grafting QP and SA onto CS. With the grafting of SA and QP onto CS, not only the crystallinity of CS molecules decreased and the water solubility improved, but also the antibacterial activity of CS-QP-SA against Escherichia coli and Staphylococcus aureus, and Colletotrichum gloeosporioides (anthracnose) improved by the synergistic effect of QP and SA. After 20 days storage, the mango fruits treated by CS-QP-SA had a weight loss rate of 12.86 %, the fruit decay incidence was 52.00 ± 1.70 %. Hence, the CS-QP-SA films effectively extending the storage time of mango fruits to a certain extent. The results of this study indicated that CS-QP-SA might be a promising preservative for fruits and vegetables.


Assuntos
Quitosana , Mangifera , Quitosana/farmacologia , Antibacterianos/farmacologia , Frutas , Staphylococcus aureus , Escherichia coli , Mangifera/microbiologia , Água/farmacologia
17.
Biomolecules ; 12(11)2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36358951

RESUMO

Creation of bio-multifunctional wound dressings with potent hemostatic, antibacterial, anti-inflammatory, and angiogenesis features for bolstering the healing of full-thickness wounds is sought after for clinical applications. We created bio-multifunctional composite sponges by coupling alginate and chitosan with Sargassum pallidum polysaccharides through electrostatic interactions, calcium ion (Ca2+) crosslinking, and lyophilization. Alginate/chitosan (AC) sponges with different concentrations of Sargassum pallidum polysaccharides were obtained and termed AC, ACS-1%, ACS-2.5%, and ACS-5%. ACS-1% and ACS-2.5% sponges exhibited uniform porosity, high water vapor transmission rate, high water absorption, as well as good hemostatic and antibacterial abilities. ACS-2.5% sponges facilitated wound closure and promoted angiogenesis and re-epithelialization in the dermis. These data suggest that ACS sponges containing a certain amount of Sargassum pallidum polysaccharides could be employed for treatment of full-thickness skin wounds.


Assuntos
Quitosana , Hemostáticos , Sargassum , Quitosana/farmacologia , Alginatos/farmacologia , Polissacarídeos/farmacologia , Antibacterianos/farmacologia
18.
Food Chem ; 387: 132878, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35421653

RESUMO

In this paper, HACC modified with (5-Carboxypentyl) (triphenyl) phosphonium bromide (HA-CS-NP) was synthesized. Then, a multifunctional food packaging composite film with good thermal stability and antibacterial functions was fabricated by HA-CS-NP and poly (vinyl alcohol) (PVA). The tensile strength and elongation at break of HA-CS-NP/PVA composite film at the weight ratio of 3/7 were 20.32 ± 1.02 MPa and 65.73 ± 3.29%, respectively. And, the inhibition rates of HA-CS-NP (0.5%) on Mango C. lagenarium and Papaya C. gloeosporioides on day 6 were up to 80.92 ± 4.12%. Compared with CK group, the weight loss of experimental groups were 23.96 ± 2.46 g/206 ± 7.25 g (mangoes) and 59.45 ± 3.06 g/496 ± 6.37 g (papaya), reduced by 35.76 ± 1.15%. Moreover, the final hardness value of the fruits coated with composite films was 4.94 ± 0.23 kg/cm3 and increased by 20.79 ± 1.04%, and the rot index was reduced by 71.43 ± 3.24%. The multifunctional HA-CS-NP/PVA coating has broad prospects in the application of food packaging.


Assuntos
Quitosana , Antibacterianos , Embalagem de Alimentos , Frutas , Fosfatos , Álcool de Polivinil , Compostos de Amônio Quaternário , Resistência à Tração
19.
Nanomaterials (Basel) ; 11(6)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208135

RESUMO

Core-shell nanofibers have great potential for bio-medical applications such as wound healing dressings where multiple drugs and growth factors are expected to be delivered at different healing phases. Compared to monoaxial nanofibers, core-shell nanofibers can control the drug release profile easier, providing sustainable and effective drugs and growth factors for wound healing. However, it is challenging to produce core-shell structured nanofibers with a high production rate at low energy consumption. Co-axial centrifugal spinning is an alternative method to address the above limitations to produce core-shell nanofibers effectively. In this study, a co-axial centrifugal spinning device was designed and assembled to produce core-shell nanofibers for controlling the release rate of ibuprofen and hEGF in inflammation and proliferation phases during the wound healing process. Core-shell structured nanofibers were confirmed by TEM. This work demonstrated that the co-axial centrifugal spinning is a high productivity process that can produce materials with a 3D environment mimicking natural tissue scaffold, and the specific drug can be loaded into different layers to control the drug release rate to improve the drug efficiency and promote wound healing.

20.
Int J Biol Macromol ; 173: 591-606, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33508359

RESUMO

Chitosan-based thermosensitive hydrogels have been widely used in drug delivery and tissue engineering, but their poor bioactivity has limited their further applications. Integral active oyster peptide microspheres (OPM) with an average particle diameter of 3.9 µm were prepared with high encapsulation efficiency (72.8%) and loading capacity (11.9%), exhibiting desirable sustained release effects. Using catechol functionalized chitosan (CS-C) as the polymeric matrix, OPM as the filler, and ß-sodium glycerophosphate (ß-GP) as a thermal sensitizer, the thermosensitive hydrogel CS-C/OPM/ß-GP was prepared. Besides, the application of the hydrogel on wound healing was studied, and its biosafety was evaluated. The results of cell migration in vitro showed that the cell migration rate of CS-C/OPM/ß-GP reached 97.47 ± 5.41% within 48 h, indicating that the hydrogel accelerated the migration of L929 cells. As demonstrated in the mouse skin wound experiment, CS-C/OPM/ß-GP hydrogel not only inhibited the aggregation of diversified inflammatory cells and accelerated the generation of collagen fibers and new blood vessels of the wound, but also enhanced the synthesis of total protein (TP) in granulation tissue, and up-regulated the expression of Ki-67 and VEGF in the injury, thereby achieving fast wound healing. Safety evaluation results showed that CS-C/OPM/ß-GP hydrogel was not cytotoxic to L929 cells, and the hemolysis ratio was less than 5% within 1 mg/mL. In conclusion, CS-C/OPM/ß-GP hydrogel is expected as a promising medical dressing for wound healing.


Assuntos
Antibacterianos/administração & dosagem , Catecóis/administração & dosagem , Quitosana/administração & dosagem , Ostreidae/metabolismo , Peptídeos/química , Pele/lesões , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Catecóis/química , Catecóis/farmacologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Glicerofosfatos/química , Hemólise , Hidrogéis , Camundongos , Microesferas , Pele/efeitos dos fármacos
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