Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Biol Macromol ; : 133525, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945317

RESUMO

To reduce environmental pollution and improve human health, developing green active food packaging materials is very necessary. In this study, a novel antioxidant and antibacterial composite film was produced by incorporating inclusion complex (CDIC) of cannabidiol (CBD) with 2,6-di-O-methyl-ß-cyclodextrin (DM-ß-CD) into pectin. The pectin films loaded with CBD and hemp leaf water extract (HLE) were prepared for comparison. Comprehensive characterizations showed CBD was encapsulated by DM-ß-CD and CDIC was evenly dispersed into pectin matrix, forming the compact and intact film. The composite films showed good mechanical properties and biodegradability. CDIC film showed the highest transparency and smoothness (Rrms/Rmax: 2.6/16.8 nm). The addition of bioactives reduced the water-binding capacity and CDIC film had the strongest hydrophobicity. Besides, DM-ß-CD encapsulation improved the thermal stability of CBD in CDIC film. Benefiting from encapsulation and excellent bioactivities of CBD, CDIC film showed excellent antioxidant capacity and antibacterial activity, effectively inhibiting colony growth and maintaining the strawberry color in strawberry preservation. This work could provide a novel eco-friendly candidate for food packaging material and expand the use of CBD in food industry.

2.
Int J Biol Macromol ; 269(Pt 2): 132144, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729476

RESUMO

Herein, we investigated the synergistic effects of jet milling (JM) and deep eutectic solvent (DES) pretreatment on the fractionation of grapevine lignin and the consequent enhancement of enzymatic hydrolysis. Grapevine, a substantial byproduct of the wine industry, was subjected to JM pretreatment to produce finely powdered particles (median diameter D50 = 98.90), which were then further treated with acidic ChCl-LA and alkaline K2CO3-EG DESs. The results revealed that the combined JM + ChCl-LA pretreatment significantly increased the cellulose preservation under optimal conditions (110 °C, 4 h, and 20 % water content), achieving removal rates of 74.18 % xylan and 66.05 % lignin, respectively. The pretreatment temperature and inhibitor production were reduced, resulting in a remarkable threefold increase in glucose yield compared to untreated samples. Moreover, the structural analysis of the pretreated lignin indicated an enrichment of phenolic units, leading to enhanced antioxidant and antibacterial activities, particularly in the JM pretreated samples. These findings underscore the promising potential of the synergistic JM and DES pretreatment in facilitating the efficient utilization of grapevine lignocellulosic biomass for sustainable biorefinery technologies.


Assuntos
Solventes Eutéticos Profundos , Lignina , Vitis , Lignina/química , Vitis/química , Hidrólise , Solventes Eutéticos Profundos/química , Fracionamento Químico/métodos , Antioxidantes/química , Antioxidantes/farmacologia , Biomassa , Celulose/química , Celulase/química , Celulase/metabolismo , Solventes/química , Temperatura
3.
Int J Biol Macromol ; 263(Pt 1): 130294, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382790

RESUMO

Herein, three pretreated grapevine lignins were incorporated into carboxymethyl cellulose films. The effects of traditional NaOH pretreated lignin and DES (ChCl-LA, ChCl-LA & K2CO3-EG) pretreated lignin on film properties were compared. Modern analytical techniques were employed to systematically characterize the pretreated lignin and the different CMC-lignin films. The results showed that DES lignin was of high purity, low molecular weight, and homogeneous structure. It outperformed traditional NaOH lignin in terms of compatibility with CMC, enabling it to perform its bioactivity and physicochemical functions in films. This feature effectively enhanced the hydrophobicity, UV shielding ability, water vapor barrier, thermal stability, mechanical properties, and biological activity of CMC-DES lignin film. NMR (2D HSQC) showed that the excellent antioxidant and antibacterial capabilities of CMC-DES lignin film are due to the retention of butyl (S) and p-hydroxyphenyl (H) units in DES lignin, resulting in its rich phenolic hydroxyl content. The detailed structural elucidation of DES lignin's chemical interactions with CMC provided valuable insights into the advantageous properties observed in the films, presenting innovative solutions for applications in the food packaging and preservation industries.


Assuntos
Anti-Infecciosos , Lignina , Lignina/química , Carboximetilcelulose Sódica/química , Antioxidantes/farmacologia , Antioxidantes/química , Hidróxido de Sódio , Permeabilidade , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Embalagem de Alimentos
4.
Int J Biol Macromol ; 247: 125761, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37429341

RESUMO

Herein, DES lignin was obtained by pretreatment of grapevine with a deep eutectic solvent (ChCl-LA). A novel chitosan-DES lignin composite aerogel material (CS-LIG aerogel) was prepared to adsorb methylene blue (MB), Congo red (CR), catechin (C), and epicatechin (EC). The CS-LIG aerogel was systematically characterized by modern technological instruments. It was demonstrated that the DES lignin was successfully incorporated and had an important effect on the morphological structure and adsorption of dyes and natural products in the aerogel. The adsorption kinetic models for both adsorbed CR and MB are pseudo-second-order models. Adsorption isotherms followed Langmuir for the adsorption of CR and Freundlich for the adsorption of MB. The π-π interaction and hydrogen bonding of DES lignin aromatic groups in CS-LIG aerogels were responsible for the adsorption of C and EC with 86.42 % and 90.85 % removal rates, respectively. This study opens a new avenue for the high-value utilization of DES lignin and the preparation of chitosan-based composites for the adsorption of dyes and purification of natural products.


Assuntos
Catequina , Quitosana , Poluentes Químicos da Água , Corantes/química , Lignina/química , Quitosana/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Vermelho Congo , Azul de Metileno/química , Poluentes Químicos da Água/química
5.
Chem Biodivers ; 20(7): e202300169, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37382028

RESUMO

Natural antioxidants play an important role in promoting good health because of their prevention for oxidative damage. The work aimed to explore the antioxidant mechanism and activity of cannabidiol (CBD) at the cellular level. The human umbilical vein endothelial cell (HUVEC) with oxidative damage was employed as the model to study the protective capability of CBD. The results showed that CBD pre-treatment before the cells were exposed to hydrogen peroxide (H2 O2 ) resulted in an obvious increase of cell viability (about 100 %) and antioxidant related enzymes activity, and a decline of malondialdehyde (MDA) level. Besides, CBD could alleviate the increase of intracellular reactive oxygen species (ROS) content, the contraction of nucleus, and condensation of chromatin. The changes showed a dose-dependent effect. Additionally, the free radicals scavenging capacity of CBD was comparable to that of typical natural antioxidant, anthocyanidins. In summary, CBD could be employed as a potent antioxidant source for avoiding the oxidative damage. These results could provide the foundation for the development of CBD antioxidant products.


Assuntos
Antioxidantes , Canabidiol , Humanos , Células Endoteliais da Veia Umbilical Humana , Antioxidantes/farmacologia , Peróxido de Hidrogênio/toxicidade , Canabidiol/farmacologia , Superóxido Dismutase/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio , Apoptose
6.
Int J Biol Macromol ; 245: 125507, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37355072

RESUMO

In this study, five polysaccharides were extracted from processed Cistanche deserticola. The processing included crude product, enzymatic hydrolysis, hot air drying, stir-baking with wine and high-pressure steaming, and these polysaccharides were named as CP-CDPs, EH-CDPs, HAD-CDPs, SBW-CDPs and HPS-CDPs, respectively. The structural characteristics and biological activities were explored. The results showed that processing changed properties of C. deserticola polysaccharides. CP-CDPs had the highest brightness value L*(93.84) and carbohydrate content (61.27 %). EH-CDPs had minimum Mw (1531.50 kDa), while SBW-CDPs had maximum Mw (2526.0 kDa). Glucose was major predominant monosaccharide in CP-CDPs (89.82 %), HAD-CDPs (79.3 %), SBW-CDPs (59.41 %) and HPS-CDPs (63.86 %), while galactose was major monosaccharide in EH-CDPs (29.44 %). According to SEM, SBW-CDPs showed compact structures, while HPS-CDPs and HAD-CDPs had similar looser structure than SBW-CDPs; meanwhile, CP-CDPs showed irregular agglomeration shape and EH-CDPs was dense blocky shape. The AFM showed SBW-CDPs had the largest molecular chain than other polysaccharides. When scavenging activity reaching 50 %, the concentrations of CP-CDPs, EH-CDPs, HAD-CDPs, SBW-CDPs, HPS-CDPs are 2.25, 0.25, 0.75, 1.8 and 1.5 mg/mL, respectively. This study sheds light on the effects of traditional Chinese medicine processing on characteristics, bioactivities of C. deserticola polysaccharides, and provides the basis for applications in food and pharmaceutical industries.


Assuntos
Antioxidantes , Cistanche , Antioxidantes/farmacologia , Antioxidantes/química , Cistanche/química , Extratos Vegetais/química , Vapor , Polissacarídeos/farmacologia , Polissacarídeos/química
7.
Food Res Int ; 168: 112783, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37120229

RESUMO

Jet milling is a common technique in ultrafine powder preparation field. It has never been used to design delivery systems. Cannabidiol (CBD) is an important cannabinoid of hemp but poor aqueous solubility limited its applications. In this study, solid dispersion (SD) technique was combined with cyclodextrin complexation technique, and jet milling was used for the first time to prepare SDs for improving CBD solubility. Different characterizations demonstrated that the dispersion effect and complexation structure of CBD SD3 prepared by jet milling were comparable to that of CBD SD2 prepared by spray drying (a common solution-based method), and were better than that of CBD SD1 prepared by cogrinding. The water solubility of CBD was increased to 20.902 µg/mL (909-fold) in CBD SD3. Besides, the antioxidant activity and cytotoxicity to tumor cells of CBD were enhanced by dispersion. This work indicated that jet milling, as a new technique with low cost and excellent applicability, could be further developed for the delivery of food functional factors or bioactive molecules.


Assuntos
Canabidiol , Canabidiol/química , Solubilidade , Água/química , Pós/química
8.
Int J Biol Macromol ; 236: 123977, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36906200

RESUMO

Deep eutectic solvents (DESs) have been extensively applied to pretreat lignocellulose; however, comparative research on acidic and alkaline DES pretreatment is relatively lacking. Herein, pretreatment of grapevine agricultural by-products with seven DESs were compared in terms of removal of lignin and hemicellulose and component analysis of the pretreated residues. Among the tested DESs, both acidic choline chloride-lactic (CHCl-LA), and alkaline potassium carbonate-ethylene glycol (K2CO3-EG) were effective in delignification. Thereafter, the CHCl-LA and K2CO3-EG extracted lignin was compared by analyzing their physicochemical structure changes and antioxidant properties. The results showed that the thermal stability, molecular weight, and phenol hydroxyl percentage of CHCl-LA lignin were inferior to K2CO3-EG lignin. It was found that the high antioxidant activity of K2CO3-EG lignin was mainly attributed to the abundant phenol hydroxyl, guaiacyl (G), and para-hydroxy-phenyl (H). By comparing acidic and alkaline DES pretreatments and their lignin nuances in biorefining, novel insights are derived for the scheduling and selection of DES for lignocellulosic pretreatment.


Assuntos
Antioxidantes , Lignina , Lignina/química , Antioxidantes/farmacologia , Solventes Eutéticos Profundos , Solventes/química , Biomassa , Colina/química , Fenóis , Hidrólise
9.
J Org Chem ; 87(22): 15301-15311, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36321357

RESUMO

A novel protocol for the construction of highly functionalized indolizine derivatives, that is, 1H-pyrrolo[3,4-b]indolizine-1,3-diones (PIZDOs, 3) from 2-(pyridine-2-yl)acetates and maleimides via a regioselective oxidative [3 + 2] annulation was developed. The cascade oxidative reaction was enabled by heating a mixture of the two substrates in the presence of Ag2CO3 as an oxidant and Cu(OAc)·H2O as a catalyst in chlorobenzene. Consequently, a series of PIZDOs 3 were synthesized with high regioselectivity in moderate yields. This protocol can be used in the synthesis of functionalized PIZDOs via the one-pot oxidative annulation reaction rather than through multistep reactions, which is suitable for both combinatorial and parallel syntheses of PIZDOs.

10.
Molecules ; 27(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36296648

RESUMO

In this study, a green process of ß-cyclodextrin (ß-CD)-assisted extraction of active ingredients from Forsythia suspensa leaves was developed. Firstly, the optimal process of extraction was as follows: the ratio between Forsythia suspensa leaves and ß-CD was 3.61:5, the solid-liquid ratio was 1:36.3, the temperature was 75.25 °C and the pH was 3.94. The yields of forsythoside A, phillyrin and phillygenol were 11.80 ± 0.141%, 5.49 ± 0.078% and 0.319 ± 0.004%, respectively. Then, the structure characteristics of the ß-CD-assisted extract of Forsythia suspensa leaves (FSE-ß-CD) were analyzed using powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and molecular docking to demonstrate that the natural active products from Forsythia suspensa leaves had significant interactions with the ß-CD. Additionally, the loss of forsythoside A from aqueous FSE-CD at 80 °C was only 12%, compared with Forsythia suspensa leaf extract (FSE) which decreased by 13%. In addition, the aqueous solubility of FSE-CD was significantly increased to 70.2 g/L. The EC50 for scavenging DPPH and ABTS radicals decreased to 28.98 ug/mL and 25.54 ug/mL, respectively. The results showed that the ß-CD-assisted extraction process would be a promising technology for bioactive compounds extracted from plants.


Assuntos
Ciclodextrinas , Forsythia , beta-Ciclodextrinas , Forsythia/química , Espectroscopia de Infravermelho com Transformada de Fourier , Simulação de Acoplamento Molecular , Pós , Extratos Vegetais/química
11.
J Agric Food Chem ; 68(4): 1101-1109, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31904947

RESUMO

ε-Poly-l-lysine (ε-PL) consists of 25-35 lysine residues which are linked by an isopeptide bond formed by dehydration condensation of α-carboxyl and ε-amino groups and has good antibacterial activity and broad-spectrum inhibition range. However, there is no clear conclusion about the structure and antibacterial mechanism of ε-PL in aqueous solution. Herein, a high purity of ε-PL was prepared using Amberlite IRC-50 ion-exchange resin. Membrane filtration and dynamic light scattering were used to study the variations of ε-PL aggregation in aqueous solution with pH value. The conformational changes and antibacterial activities of ε-PL and carbamoylated ε-PL in different water environments were studied with circular dichroism (CD) and inhibition zone. The structural changes during the spray-drying process were determined by Fourier transform infrared spectroscopy. The results indicated that the side chain amino charge played a decisive role in the ε-PL conformation and aggregation. ε-PL exhibited the properties of a ß-sheet during spray drying from acidic liquids to solids. The cation enhanced the antibacterial activity of ε-PL but did not play a key role. Instead, the backbone of ε-PL might determine the mechanism of ε-PL antibacterial.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Polilisina/química , Polilisina/farmacologia , Antibacterianos/metabolismo , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Transição de Fase , Polilisina/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Streptomyces/química , Streptomyces/metabolismo
12.
J Food Sci ; 83(4): 966-974, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29524221

RESUMO

A novel technique of ultrasound-assisted freeze-thaw pretreatment (UFP) was developed to improve the drying efficiency of maca and bioactive amide synthesis in maca. The optimal UFP conditions are ultrasonic processing 90 min at 30 °C with 6 freeze-thaw cycles. Samples with freeze-thaw pretreatment (FP), ultrasound pretreatment (UP), and UFP were prepared for further comparative study. A no pretreatment (NP) sample was included as a control. The results showed that UFP improved the drying efficiency of maca slices, showing the highest effective moisture diffusivity (1.75 × 10-9 m2 /s). This result was further supported by low-field nuclear magnetic resonance (LF-NMR) analysis and scanning electron microscopy (SEM). The rehydration capacity and protein content of maca slices were improved by UFP. More importantly, contents of bioactive macamides and their biosynthetic precursors were increased in 2.5- and 10-fold, respectively. In conclusion, UFP is an efficient technique to improve drying efficiency, physicochemical properties, and bioactive macamides of maca, which can be applied in the industrial manufacture of maca products.


Assuntos
Manipulação de Alimentos/métodos , Lepidium/química , Preparações de Plantas/química , Proteínas Alimentares/análise , Congelamento , Humanos , Extratos Vegetais/biossíntese , Ondas Ultrassônicas , Água
13.
Mater Sci Eng C Mater Biol Appl ; 72: 185-191, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28024576

RESUMO

In this study, we have aimed to prepare folic acid-conjugated dextran stearate (DF) polymeric micelles to target resveratrol in lung cancers. The polymeric micelle was nanosized and exhibited a controlled drug release pattern. The resveratrol (RSV)-loaded dextran stearate (RSV-DF) micelles exhibited an enhanced cellular uptake in A549 cells due to the folic acid-based receptor interactions. We have demonstrated that RSV-DF polymeric micelles retain the cytotoxic and metabolic effects of RSV on A549 cancer cells with potencies similar to that of the free compound. Furthermore, RSV-DF showed an enhanced cellular apoptosis of cancer cells compared to that of free RSV. We have found that apoptosis induced by RSV-DF was associated with the higher expression of p53, caspase-3, and BAX than the free RSV. The higher level of BAX and caspase-3 further indicates the involvement of mitochondria-dependent apoptosis in the anticancer efficacy of formulations. Based on these results, it can be concluded that natural compound like RSV could be an interesting prospect to treat lung cancers and the fact that folic acid-conjugated dextran stearate could be a potential carrier to deliver the drug in the cancer cells.


Assuntos
Dextranos/química , Ácido Fólico/química , Estilbenos/química , Células A549 , Antineoplásicos/química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Caspase 3/metabolismo , Liberação Controlada de Fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Tamanho da Partícula , Resveratrol , Estilbenos/toxicidade , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
15.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 3917-3918, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-25541310

RESUMO

Mitochondrial genome plays a central role in aging, cancer, apoptosis and metabolism. We sequenced a complete mitochondrial genome sequence of a rat chronic obstructive pulmonary disease rat strain for the first time. The total length of the mitochondrial genome was 16,310 bp and coding 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes. This genome describing information will supply the potential use of mtDNA mutations as markers in cancer.


Assuntos
Genoma Mitocondrial , Doença Pulmonar Obstrutiva Crônica/genética , Animais , Códon de Iniciação , Códon de Terminação , DNA Mitocondrial/química , DNA Mitocondrial/isolamento & purificação , DNA Mitocondrial/metabolismo , Modelos Animais de Doenças , Complexo IV da Cadeia de Transporte de Elétrons/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , NADH Desidrogenase/química , NADH Desidrogenase/genética , NADH Desidrogenase/metabolismo , Fases de Leitura Aberta/genética , Doença Pulmonar Obstrutiva Crônica/patologia , RNA Ribossômico/química , RNA Ribossômico/genética , RNA de Transferência/química , RNA de Transferência/genética , Ratos , Análise de Sequência de DNA
16.
Chin J Nat Med ; 13(9): 653-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26412424

RESUMO

Maca (Lepidium meyenii) is an herbaceous plant that grows in high plateaus and has been used as both food and folk medicine for centuries because of its benefits to human health. In the present study, ITS (internal transcribed spacer) sequences of forty-three maca samples, collected from different regions or vendors, were amplified and analyzed. The ITS sequences of nineteen potential adulterants of maca were also collected and analyzed. The results indicated that the ITS sequence of maca was consistent in all samples and unique when compared with its adulterants. Therefore, this DNA-barcoding approach based on the ITS sequence can be used for the molecular identification of maca and its adulterants.


Assuntos
DNA Intergênico/análise , DNA de Plantas/análise , Contaminação de Medicamentos/prevenção & controle , Lepidium/genética , Código de Barras de DNA Taxonômico/métodos , Humanos , Fitoterapia
17.
J Mater Sci Mater Med ; 21(8): 2435-42, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20502948

RESUMO

The aim of this paper was to evaluate the application potential of CS-HTCC/GP-0.1%Chx thermosensitive hydrogel which was synthesized using chitosan (CS), quaternized CS, and alpha,beta-glycerophosphate (alpha,beta-GP) loading with 0.1% chlorhexidine (Chx) (w/v) for periodontal treatment. An aqueous solution of CS-HTCC/GP-0.1%Chx was transformed into hydrogel at 6 min when the temperature was increased to 37 degrees C. The scan electron microscopy (SEM) image of the gel was a porous, loose and crosslinked network. In vitro, Chx released over 18 h from the CS-HTCC/GP thermosensitive hydrogel in artificial saliva pH 6.8. Release rate could be controlled through adjustment of alpha,beta-GP or Chx concentration. CS-HTCC/GP-0.1%Chx thermosensitive hydrogel exhibited excellent inhibitory activity against primary periodontal pathogens. CS-HTCC/GP-0.1%Chx thermosensitive hydrogel had no acute toxicity; the maximum tolerated dose in rats was 400 mg/ml. All results indicated that CS-HTCC/GP-0.1%Chx thermosensitive hydrogel is a strong candidate as a local drug delivery system for periodontal treatment.


Assuntos
Clorexidina/administração & dosagem , Hidrogel de Polietilenoglicol-Dimetacrilato/administração & dosagem , Hidrogel de Polietilenoglicol-Dimetacrilato/efeitos adversos , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Doenças Periodontais/tratamento farmacológico , Animais , Anti-Infecciosos Locais/administração & dosagem , Anti-Infecciosos Locais/farmacocinética , Clorexidina/farmacocinética , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/efeitos adversos , Portadores de Fármacos/síntese química , Portadores de Fármacos/farmacocinética , Estabilidade de Medicamentos , Feminino , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacocinética , Injeções , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Modelos Biológicos , Ratos , Temperatura , Testes de Toxicidade
18.
J Mater Sci Mater Med ; 20(8): 1603-10, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19322644

RESUMO

A novel injectable thermosensitive hydrogel (CS-HTCC/alpha beta-GP) was successfully designed and prepared using chitosan (CS), quaternized chitosan (HTCC) and alpha,beta-glycerophosphate (alpha,beta-GP) without any additional chemical stimulus. The gelation point of CS-HTCC/alpha beta-GP can be set at a temperature close to normal body temperature or other temperature above 25 degrees C. The transition process can be controlled by adjusting the weight ratio of CS to HTCC, or different final concentration of alpha,beta-GP. The optimum formulation is (CS + HTCC) (2% w/v), CS/HTCC (5/1 w/w) and alpha,beta-GP 8.33% or 9.09% (w/v), where the sol-gel transition time was 3 min at 37 degrees C. The drug released over 3 h from the CS-HTCC/alpha,beta-GP thermosensitive hydrogel in artificial saliva pH 6.8. In addition, CS-HTCC/alpha,beta-GP thermosensitive hydrogel exhibited stronger antibacterial activity towards two periodontal pathogens (Porphyromonas gingivalis, P.g and Prevotella intermedia, P.i). CS-HTCC/alpha, beta-GP thermosensitive hydrogel was a considerable candidate as a local drug delivery system for periodontal treatment.


Assuntos
Quitosana/química , Quitosana/uso terapêutico , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Hidrogel de Polietilenoglicol-Dimetacrilato/uso terapêutico , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Infecções por Bacteroidaceae/tratamento farmacológico , Quitosana/administração & dosagem , Quitosana/análogos & derivados , Quitosana/síntese química , Estabilidade de Medicamentos , Glicerofosfatos/administração & dosagem , Glicerofosfatos/química , Glicerofosfatos/uso terapêutico , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/administração & dosagem , Bombas de Infusão Implantáveis , Injeções Intralesionais , Testes de Sensibilidade Microbiana , Doenças Periodontais/tratamento farmacológico , Doenças Periodontais/etiologia , Doenças Periodontais/microbiologia , Porphyromonas gingivalis/efeitos dos fármacos , Prevotella intermedia/efeitos dos fármacos , Espectrofotometria Infravermelho , Temperatura , Termodinâmica , Viscosidade
19.
J Biomed Mater Res A ; 91(4): 1065-76, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19107793

RESUMO

In the study, we intend to design a suitable localized drug delivery system (LDDS) with chitosan and poly vinyl alcohol (PVA) for treating serve periodontitis. For that, a novel formulation based on the incorporation of chitosan-based microspheres into PVA film was prepared. As the core parts of the novel formulation, chitosan-based microspheres were prepared form chitosan and/or carboxymethyl-chitosan (CM-chitosan) by using water-in-oil emulsification method. Then basic in vitro and in vivo experiments focusing on biocompatibility and biodegradability of the two chitosan-based microspheres were carried out to evaluate the feasibility of the novel LDDS. In vitro tests, besides having no hemolysis, chitosan microsphere (Cs1-Ms), and CM-chitosan microsphere (Cs2-Ms) have adsorbed little proteins on their surfaces. Moreover, plasma proteins adsorbed on Cs2-Ms, most of which can easily desorbed, are much less than that adsorbed on Cs1-Ms. This indicates that Cs2-Ms perhaps has better biocompatibility than Cs1-Ms. In vivo tests, Cs1-Ms and Cs2-Ms were subcutaneously implanted in rat to investigate the host tissue inflammatory response. Implantations of Cs1-Ms and Cs2-Ms induced a little more severe inflammation when compared with the implantation of PVA film. However, the difference on in vivo biocompatibility between Cs1-Ms and Cs2-Ms could not be confirmed by the implantation model of our experiments. Both Cs1-Ms and Cs2-Ms had suffered bioerosion when they were subcutaneously implanted. The hard and compact matrixes of Cs1-Ms were degraded very slowly, and only some trifling degradation had been found until 4 weeks of implantation. In contrast, Cs2-Ms is soft and more hydrophilic, and can be quickly degraded in a form of diffluence by the physiological circumstance. All these results suggested that Cs2-Ms had better potentials used as core parts of the novel designed LDDS in the future developments.


Assuntos
Quitosana/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Periodontite/terapia , Álcool de Polivinil/farmacologia , Adsorção/efeitos dos fármacos , Animais , Bovinos , Eletroforese em Gel de Poliacrilamida , Feminino , Fibrinogênio/metabolismo , Fibrinogênio/ultraestrutura , Corpos Estranhos/imunologia , Hemólise/efeitos dos fármacos , Humanos , Implantes Experimentais , Microesferas , Ratos , Ratos Wistar , Soroalbumina Bovina/metabolismo , Solubilidade/efeitos dos fármacos , Tela Subcutânea/efeitos dos fármacos , Tela Subcutânea/imunologia , Tela Subcutânea/ultraestrutura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...